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Vuwb5FeIkuxV6Cq1	29.5: Key Terms	Skip to main content - absorption - the passage of digested products from the intestinal lumen through mucosal cells and into the bloodstream or lacteals - alimentary canal - the digestive tract from the mouth to the anus - amylase - an enzyme in the saliva and pancreatic juice that catalyzes the breaking down of starch, glycogen, and related polysaccharides into more simple and readily usable forms of sugar - aspiration - the inhalation of fluid or solid objects into the lower airways or lungs - bile - alkaline solution produced by the liver and important for the emulsification of lipids - chyme - the mixture of partly digested food and digestive secretions found in the stomach and small intestine during the digestion of a meal; it is a varicolored, thick, nearly liquid mass - digestion - the process by which food is broken down mechanically and chemically in the gastrointestinal tract and converted to absorbable forms - epiglottis - the uppermost cartilage of the larynx located immediately posterior to the root of the tongue; covers the entrance of the larynx when a person swallows and prevents food or liquids from entering the airway - gastritis - acute or chronic inflammation of the stomach lining - gastroesophageal reflux disease (GERD) - a common condition in which acid from the stomach (gastric and/or duodenal) flows back into the esophagus, causing discomfort and, in some instances, damage to the esophageal lining - hydrochloric (HCl) acid - an inorganic acid normally present in gastric juice; destroys fermenting bacteria that might cause intestinal tract disturbances - ingestion - the process of taking substances (particularly food) into the gastrointestinal tract - lipase - pancreatic enzyme that breaks down triglycerides into free fatty acids and glycerol to be used in the body - lower esophageal sphincter - the sphincter around the opening of the esophagus into the stomach; separates these linked organs from each other and prevents the reflux of stomach acids into the esophagus; also called the cardiac sphincter - mastication - chewing; involves coordination of the large temporal, masseter, and pterygoid muscles as well as other smaller muscles of the mandible and tongue to grind food under the influence of the mandibular division of cranial nerve V - metabolism - sum of all of the body’s chemical reactions - pepsin - the chief enzyme of gastric juice, which converts proteins into proteoses and peptones; formed by the chief cells of gastric glands and producing its maximum activity at a pH of 1.5–2 - pepsinogen - the antecedent of pepsin existing in the form of granules in the chief cells of gastric glands - peristalsis - muscular contractions and relaxations that propel food through the GI tract - protease - pancreatic enzyme that breaks down proteins in the diet; also provides protection from organisms that may live in the intestines, such as certain bacteria and yeast - saliva - the fluid secretion of the salivary glands and oral mucous gland that begins the process of food digestion; moistens food for tasting, chewing, and swallowing; initiates digestion of starches; moistens and lubricates the mouth; acts as a solvent for excretion of waste products; also known as spit or spittle - upper esophageal sphincter - a sphincter that keeps the opening between the posterior pharynx and the proximal esophagus closed, except during swallowing; maintained principally by the cricopharyngeal muscle	730	common-pile/libretexts_filtered	https://med.libretexts.org/Bookshelves/Nursing/Pharmacology_for_Nurses_(Openstax)/29%3A_Introduction_to_the_Digestive_System/29.05%3A_Key_Terms	libretexts	libretexts-0000.json.gz:15268	https://med.libretexts.org/Bookshelves/Nursing/Pharmacology_for_Nurses_(Openstax)/29%3A_Introduction_to_the_Digestive_System/29.05%3A_Key_Terms
GDqrexkePz98so3I	Our country and its resources; what we ought to know about agriculture--fisheries--forests--Panama canal--railroads--manufactures--automobiles--industrial preparedness--the new navy--the army--our money--aeronautics--motion pictures--the weather--astronomy--the nation's capital--the President--Congress--all about the government, by Albert A. Hopkins ... with 800 illustrations ...	ITS RESOURCES WHAT WE OUGHT TOkNOW ABOUT AGRICULTURE -FISHERIES FORESTS- PANAMA CANAL-RAILROADS-MANUFACTURES AUTOMOBILES - INDUSTRIAL PREPAREDNESS - THE NEW NAVY-THE ARMY-CUR MONEY-AERONAUTICS-MOTION PICTURES-THE ALBERT A. HOPKINS Member of the American Statistical 'Association Editor of the Scientific American Reference Book Scientific American Cyclopedia of Formulas, etc. This book is protected by ninety copyrights and all persons are warned against any use of text or illustrative material. PREFACE /T"SHE "Wave of Prosperity" which has raised our counA try to an unparalleled position need not ever recede if we take measure of our resources and their development at the present time and act wisely upon the information obtained. It is the object of this modest volume to present such facts as can be obtained from official sources, in a readable and withal likable form, so that we may have a more wholesome respect for what Uncle Sam is doing for us. The "Stars and Stripes" are protected by Acts of Congress and State laws; the American Eagle cannot be kept in captivity (except in a zoological garden), but the power of the law has never been invoked to protect that symbol of our Federal Government — "Uncle Sam." This kindly old gentleman with his fuzzy beaver hat, his striped trousers and his parti-colored coat of the period of 1830, is used dozens of times daily in cartoons, but always in a respectful sense as we use it here — as a symbol of national esteem. There is no more fascinating story in the world than how we are governed by means of often invisible threads that seem to begin nowhere, but always end somewhere to our profit and often pleasure. Who shall tell this wonderful story of achievement? How five blades of grass are made to grow where two should be found; how fish that have been left high and dry on land after a- flood are put back in water to prevent "air drowning;" how forests are conserved at a profit; how reclamation makes the desert smile ; how national parks can be run for both profit and pleasure; how good roads decrease the cost of living; how the three great Government Surveys carry on their ceaseless work to exploit our resources, or chart the fairways of commerce; how the Coast Guard is always on the lookout to protect life and property at sea; how the Patent Office has succeeded in making us a nation of inventors and quadrupling our national wealth; how commercial and industrial preparedness have changed the gears on the car of industrial progress — all these and many more remain to be told. Who shall tell the story? Why not "let Uncle Sam do it" ? He is patient, kind, amiable, and exceedingly accurate in his information. This is what has been done here. Uncle Sam tells his complex story in his own way with the pen of high Government officials — cabinet officers, heads of the great governmental manufacturing plants and bureaus under Government auspices, down the list until all of the Government activities are accounted for. Unfortunately, the names cannot always be published, owing to departmental regulations, but enough names have been printed throughout the book to stamp this as a very authentic, and make it practically a semi-official guide to Government activities. In the section known as ' 'Uncle Sam's Autobiography" every chapter has been submitted to either the Secretary of the Department, or to some responsible officer for revision. This has required an almost endless correspondence, but the Editor has the satisfaction of knowing that the information is as nearly right as it is possible to get it. Besides Government officials, named and unnamed, special thanks are due to Mr. C. F. Talman, Librarian of .the U. S. Weather Bureau; Dr. F. L. Hoffman, Statistician of the Prudential Insurance Company; Dr. Richard Rathbun of the Smithsonian Institution; Mr. Louis Annin Ames, an authority on flags, and a number of others who have given their kind assistance. Adequate pictorial treatment heightens the interest of this fascinating subject, and the whole country has been canvassed for interesting pictures; thus, for the chapter on Agriculture, over 35,000 photographs were examined to select the significant ones. It is hoped that this book will be a real contribution to literature on true preparedness — preparedness for the arts of peace, as well as the arts of war. The Panama Canal ::: The Three Great Government Surveys Government Protection of Life and Property at Sea Railroads of the United States : : The Postal Service : : : Taken fcy Captain Amundsen Himself Copyright by Underwood & Underwood CAPT. ROALD AMUNDSEN, WHO DISCOVERED THE SOUTH POLE ON DECEMBER 14, 1911. Christopher Columbus, with three small vessels, carrying 88 men, sailed into the Unsnown from Palos, Spain, on August 3, 1492. The significance of thie voyage was not only that it brought to light the Western World, but that it also disclosed the sea a? the great highway of men by which they soon learned to reach all the vast islands (continents) and the lesser islands of the globe. Europe, for example, had a very misty idea of China and India till sea routes placed her in touch with them. Sea routes hugged the coasts of Europe and Africa for thousands of miles; but Columbus added cross sea sailing to the coast routes and thus brought in the day of worldwide exploration. The Vikings of Norway in the ninth-tenth centuries A. D. had discovered Iceland, Greenland and the northeast coast of North America ; but these daring sea rovers were far from European centers; and as it was thought that Greenland was a part of Europe, their work was not at all appreciated, and, in fact, was very little known. 1503, brought to light the larger and many of the smaller islands of the West Indies. He saw South America from the island of Trinidad and noted the freshness of the Gulf of Paria's waters which come from the Orinoco. He skirted the eastern shores of Central America from Guanaja Island, around Cape Gracias a Dios, paused at Bel£n on the Isthmus of Panama, thence on to Puerto Bello, the most southern point he reached. His field of discovery embraced the area between about 9 to 24 degrees North Latitude and 60 to 87 degrees West Longitude. At St. Ann's Bay, on the north coast of Jamaica, he ended his great began it. Immediate effects of his achievement were apparent. Ten days less than a year after Columbus started on his third voyage to America, Vasco da Gama, after rounding the Cape of Good Hope, landed at Calicut, the first European navigator to reach India. This was the beginning of the great sea-trade between Europe and the East Indies. Thirteen years and 3 months after Columbus died, Magellan started on his journey around the world (1519- PROGRESS OF GEOGRAPHICAL DISCOVERT 21), was the first to pass through the Straits of Magellan, gave to the Pacific the flattering name it bears and his expedition circumnavigated the world though its leader perished in the Philippines. Among the other most notable circumnavigations were those of Sir Francis Drake (157780), during which he sailed along the Pacific coast of America from Magellan Straits nearly to Puget Sound, seeking in vain for a waterway into the Atlantic ; Admiral Spilberg, who led a small Dutch fleet around the world (1614-17), incidentally defeating a Spanish fleet off Chile; and Captain James Cook, time discoverers. It was early in the 16th century that Amerigo Vespucci, an Italian adventurer, claimed that he had made four voyages to America, though not as the commander of any expedition. The dates he gave were 1497, 1499, 1501 and 1503. From the time that his writings were critically examined by Alexander von Humboldt, the prevalent opinion has been that he had no part whatever in the first discovery of continental America. Professor Martin Waldseemiiller of Lorraine unfortunately gave full credence to Vespucci's claims, wrote a book in 1507 in which he said the newly discovered continent should be called Air erica because "Americus discovered it," and published the first map on which the name America appeared. It was the blunder of a scholar that attached the name America instead of "Columbia" to the Western World. When John Cabot reached the northeastern coast of North America (1497) and landed on Cape Breton Island at the entrance to the Gulf of St. Lawrence, he believed he had reached the eastern shores of Asia. He returned home to announce the news and, the following year, went back to follow the whole coast and locate Japan in the south. This journey extended from Greenland nearly as far south as the latitude of Philadelphia, but as he found no signs of civilization and his supplies were running short, he returned to England. V. Y. Pinson, who was helpful to Columbus on his first voyage, discovered in 1500 the estuary of the Amazon, the largest river in the world. This was about 17 years after Diego Cam found the mouth of the Congo, the second greatest river. About this time the idea began to weaken that the shores which explorers had been visiting were coasts of Asia. The population was too scanty and none of it was civilized ; but still, no explorer was instructed to find what these new lands were worth and how they might be utilized. The main idea, for a long time, was to hunt for waterways through the new lands by which the spices of the East Indies and other coveted Asian commodities might be brought to the Atlantic countries of Europe without doubling the Cape of Good Hope. It was while hunting for such a passage, and by reason of stress of weather, that Pedro Alvarez Cabral, in 1500, sighted the coast of Brazil, and took possession of it in the name of Portugal. In a half century, the whole Brazilian coast was studded with Portuguese settlements. The policy of appropriation and development was under way. The avowed regime of the .Portuguese was to win new lands, if possible, by preaching the Gospel to the natives; if this failed, to subjugate them by the sword. The romantic episode in coastal discovery was the voyage of Ponce de Leon, of Spain, in 1512, authorized by his government to search for and settle the fabulous island of "Bimini," on which was reputed to be a wonderful fountain that renewed the youth and strength of old men who bathed in it. He failed to find the fountain of youth, but his toil was not in vain, for he skirted a long coast covered with flowers In 1513, Vasco Nunez de Balboa heard from an Indian chief that, south of the Isthmus of Panama, was another great ocean. Climbing to the summit of the Isthmian range, Balboa saw the Pacific; and arriving at the shore on September 29, he proclaimed the "Great South Sea" to be a possession of the Spanish king. He was planning to undertake the conquest of the Peruvians for the Spanish crown when the jealous governor of the Darien colony put him to death on a trumped up charge of disloyalty. The fate of Balboa, one of the ablest men in the Spanish service, was a pathetic incident in the early history of American discovery. These data briefly summarize the leading events in discovery and early exploration along the eastern coasts of the Americas. Then followed the era of the penetration of the lands (16th-19th centuries). In North America, the gigantic task of studying the vast interior to the north of the Rio Grande was the work mainly of English and French explorers and European immigrants who followed in their wake. But many Spanish enterprises took root in the present Texas, New Mexico, Arizona and California. The Spanish over-ran the whole of Central and South America, excepting Brazil, seeking gold rather than orderly exploration and economic development, imposing upon the natives also the most cruel subjugation. But this eager quest for treasure so prodded exploratory zeal that South America was better known and mapped than North America towards the end of the 18th century. In 1516, De Solis discovered and ascended the River Plata and was killed by Indians at the delta of the Parana, near where Buenos Aires stands. In 1519-21, while Magellan was sailing around the world, Cortez, a military genius and a monster of cruelty, conquered Mexico and explored the Peninsula of Lower California. Among the great geographical results of the advancing Spanish conquest was the descent of the Amazon River from the Andes to the Atlantic by Orellana. In one of his wars with Indians, women fought beside the men of their tribe, which originated the name Amazons applied to female warriors. While the main river has been known for 300 years from the Andes to the sea, much of its basin between the main tributaries of the trunk stream still awaits detailed study. The incentive to North American exploration was long the desire to find a northwest waterway leading to the Pacific. Jacques Cartier (1536) discovered the St. Lawrence River and ascended it to the site of Montreal. He saw the Ottawa town of Quebec, traced the St. Lawrence to its source in Lake Ontario and reached Lake Huron. He was hoping all the time to find a waterway to China. Henry Hudson (1609) sailed into New York Bay and up the Hudson River to the site of Albany before he decided that the route would not lead to the Pacific. While on the same quest in Hudson Bay (IGlO), he and some of hir men were set adrift by mutinous comrades and were not heard of again. About 1660 the exploration of the continental interior- without thought of reaching the Orient, became more prominent. It has often required a number of explorers to establish a geographical fact. Thus French explorers, chiefly missionaries, as Joliet and Marquette. revealed the Mississippi between its affluents, the Wisconsin and the Arkansas, within 700 miles of the Gulf of Mexico (1660-73). Father Hennepin (1680) traced the upper Mississippi between the mouth of the Illinois River and the site of Minneapolis. Its lower course had been followed by Ferdinand de Soto (1541). De Soto has often been called the discoverer of the Mississippi, out the river was first sighted by Aionzo de Pineda in 1519. Its extreme sources and upper course were discovered and studied by later explorers, chiefly Schoolcraft (1832), Nicollet (1836), and Brower (1889). The exploration of the Great Lakes was distributed over many years. The pioneers who chopped their way through the forests from the Atlantic to the Mississippi, or opened farms in spite of Indian foes, in Kentucky, Tennessee and Ohio, the trappers and hunters spread over the western plains, the gold diggers who rushed to California, all added immensely to early knowledge of the United States. In regions that have had from early time, comparatively dense population and rapid growth in civilization, we hear little of such research as that, for example, which has gridironed Africa with explorers' routes. Communities, such as Greece, Rome, China and Japan, as they grew in intellectual power, became intense students of their own habitat ; and their armies, invading less fortunate lands, were the chief instrument of pioneer discovery. No large events in exploration have been possible in Europe within the Columbian era. Among the. most important discoveries in Asia have been these : Deshnev rounded the East Cape (Cape Deshnev) in 1645, and thus made known the most eastern extension of the continent. Russia began the scientific exploration of Siberia in 1725 and, in the next twenty years, the northern coasts were fairly well determined and a foundation was laid for the detailed study of the land surface, fauna flora and inhabitants. Bering (172541) showed the relation between the northeast coast of Asia and the northwest coast of America. In the past fifty years, the great plains and forests have been studied, the Lena, Yenesei and Ob, three of the largest rivers in the world, have been explored and the Yenesei and Ob have irregular steamship connections with European ports. One result of the study of Siberia is that over 20,000,000 acres are now under the plow. Tibet, so long a terra incognita, has been largely revealed, chiefly since 1863, by many explorers. The Himalayas have long been in process of detailed study by the Indian Survey, and India has been minutely mapped. Australia was probably first seen about 1540 by French sailors, but it was early in the next century that the Dutch brought the first authentic accounts of parts of the west coast Capt. James Cook's voyage (1769-70), when he surveyed the whole east coast, made the first great contribution to knowledge of the continent. Inland exploration did not begin till the early part of the 19th century. Attempts to penetrate the dry or desert regions of the interior with horses involved a number of tragedies, including the disappearance of the second Leichardt expedition (1847). Leichardt set out to cross the continent from east to west and was never heard from after he entered the desert. Not even in polar lands was exploration so hazardous as in Australia till the camel was introduced about 1865; then exploration advanced more rapidly and Australia is now known in all its chief configurations and conditions. The attempt to reveal the whole of Africa did not begin till Dr. David Livingstone (1841-73) completed his great work. The exploration of the continent was greatly retarded by the difficulties of getting into it, owing to the lack of indentations, the high coasts, rivers reaching the sea by cataracts and rapids, the unfavorable climate and a host of hostile native tribes. The modern era of African exploration began when OUR COUNTRY AND ITS RESOURCES Mungo Park made his journeys in the basin of the Niger River (17951806). During the next forty years, a few explorers crossed the Sahara and studied the western and central Sudan; and finally Dr. Livingstone gave thirty years of his life to many journeys of exploration in southcentral Africa. He did not live to see the great effect of his work ; but soon after his death (1873) the greatest exploratory movement ever seen began in Africa. Scores of expeditions carried on field studies that finally extended over nearly all of Africa south of the Sahara ; and seven European nations — Great Britain, France, Belgium, Germany, Italy, Spain and Portugal — were finally in possession of the whole of Africa excepting Abyssinia and Liberia. Intensive studies of. the various colonies began in the last years of the 19th century and continued till the war of 1914, when the entire work of development practically ceased. Africa, the last continent to be largely explored, has thus made far greater progress, in the short period of a generation, than any of its sister continents when they were in the same low stage of development. Nearly 58,000 Greenland whales were killed in Spitzbergen waters in a little over a century, beginning in 1670. The search for the Northwest Passage to Asia also led into the Arctic as, for example, Davis's voyage up Baffin Bay. Then the quest for the North Pole engaged expeditions for many years; and finally, not a few parties were specially equipped to seek for facts about polar phenomena. Thus many polar lands have been discovered, depths of the polar seas have been ascertained in wide areas, the Arctic natives have been studied and the art of living and traveling in the frigid zones has been far advanced. The investigation of the position of the north and south magnetic poles appears to show that they are not fixed points but move in areas of considerable extent. The attainment of the geographical North Pole was made by Peary on April 6, 1900; and of the South Pole by Amundsen on December 14, 1911, and by Scott on January 18, 1912. The most notable discovery in many years is the fact that a high continent surrounds the South Pole. The area of the land surface is approximately 5,460,000 square miles, or nearly one and a half times the OF THE NORTH POLE size of Europe. It is computed that its mean height is 6,500 feet, or nearly seven times the mean elevation of Europe. The great world sea has been so well explored that probably few islands have escaped attention except, it may be, in the polar areas. Phoenicians Invasions of Habesh, Arabia, Phoenicia. Syria. Argonautic expedition to Colchis. Voyages to Ophir, Gades, Britain. Claimed to have discovered Venezuela (which Columbus had already seen from the island of Trinidad). His testimony as to his three alleged voyages is regarded as untrustworthy. Conquest of Mexico. First to circumnavigate the globe. Passes through the Strait of Magellan, crosses the Pacific, and discovers the Philippines. Labrador and Baffin Land. Second circumnavigation of the globe, and first saw Cape Horn. Explored W. coast of N. America nearly as far as Vancouver Archipelago. Anadyr. Lake region of the St. Lawrence discovered. Exploration of the Mississippi from the north. Exploration of the coasts of Siberia. Bering Strait and the NW. coast of America. Circumnavigation of the globe. Recovered Franklin relics. Explored S. coast of Franz Josef Land. Grinnell Land and NW. coast of Greenland. Across Africa from West coast, Congo Basin. Welle-Mobangi, etc. circle. Explorations in Abyssinia and Brit. E. Africa. Found new islands W. of Parry Islands. Explorations in Congo and Zambezi headwaters. the Bureau of the Census as of April 15, 1910. The total area of enumeration included the United States, the territories of Alaska and Hawaii and Porto Rico. The enumeration also included persons stationed abroad in the military and naval service of the Government. the outlying possessions of the United States. Including the population of the Philippines and other possessions, the total population living under the American flag is approximately as given below. United States Census Bureau that the population of the United States and possessions on July 1, 1914, 55,608 The population returned for the total area of enumeration was 93,402,151, an increase, from 1900 to 1910, of 20.9 per cent for the total area of enumeration and 21 per cent for the United States, exclusive of outlying possessions. At the close of the First Census, in 1790, the United States comprised substantially the territory between the Atlantic Ocean and the Missis- sippi River except Florida, representing a gross area (land and water surface) of 892,135 square miles. The United States, with its outlying possessions, now comprises a gross area of 3,743,306 square miles, or more than four times the area in 1790. The successive accessions of territory were as given below. DENSITY OF POPULATION According to the Census of 1910, there were in the United States, on the average, 30.9 inhabitants to each Alaska had an average density of only 0.1 per square mile; Hawaii, 29.8; and Porto Rico, 325.5, or greater than that of any State of the United States except Rhode The center of population is often understood to be the point of intersection of a north and south line which divides the population equally, with an east and west line which tion, but previously considered a part of the Louisiana Purchase. square mile of land area. The relative density of population of each State of the United States in 1910 is best exhibited by the map on page 22. Aside from the District of Columbia there were ten States in which there was in 1910 a population per square mile of more than 100, as follows: Rhode Island, 508.5 inhabitants per square mile; Massachusetts, 418.8; New Jersey, 337.7; Connecticut, 231.3; New York, 191.2; Pennsylvania, 171.0; Maryland, 130.3; Ohio, 117.0; Delaware, 103.0; Illinois, 100.6. There were 16 States which had, on the average, less than 18 inhabitants to the square mile. Nevada, with 0.7 person per square mile, or 7 persons to 10 square miles, had the lowest density. Among the outlying possessions likewise divides it equally. This point of intersection is, in a certain sense, a center of population; it is, however, designated by the Bureau of the Census as the median point to distinguish it from the point technically defined as the center. The character of these two points may be made clear through a physical analogy. If the surface of the United States be considered as i rigid plane without weight capable of sustaining the population distributed thereon, individuals being assumed to be of equal weight, and each, therefore, to exert a pressure on any supporting pivotal point directly proportional to his distance from the point, the pivotal point on which the plane balances would, of course, be its center of gravity ; and this is the point referred to by the term "center of population." In de- POPULATION PER SQUARE MILE, BY STATES termining the median point, distance is not taken into account, and the location of the units of population is considered only in relation to the intersecting median lines — as being north or south of the median parallel and east and west of the median meridian. Extensive changes in the geographic distribution of the population may take place without affecting the median point, whereas the center of population responds to the slightest population change in any section of the country. At the time of the First Census, the center of population was 23 miles east of Baltimore, Maryland, since which time it has moved steadily westward. In 1800 it was 18 miles west of Baltimore; in 1810, 40 miles northwest by west from Washington, D. C. ; in 1S20, 16 miles north of Woodstock, Va. ; in 1830, 19 miles west-southwest of Moorefield, W. Va. ; in 1840, 16 miles south of Clarksburg, W. Va.; in 1850, 23 miles southwest of Parkersburg, W. Va. ; in I860, 20 miles south of Chillicothe, O. ; in 1870, 48 miles east by north of Cincinnati, O. ; in 1880, 8 miles west by south of Cincinnati, O. ; in 1890, 20 miles east of Columbus, Ind. ; in 1900, 6 miles southeast of Columbus, Ind., and finally, in 1910, in the city of Bloomington, Ind. During the 120 years between the First and Thirteenth Census, the center of population has moved over 550 miles westward, or in other words, from west latitude 76 degrees 11 minutes 12 seconds to west latitude 86 degrees 32 minutes 20 seconds. MEDIAN POINT As in the case of the center of population, the median point has also oeen moving westward, but not quite so rapidly. The exact location of the median point in 1880 was 16 miles nearly due west of Springfield, O. ; in 1890, 5 miles southwest of Greenville, O. ; in 1900, in Spartanburg, Ind., and finally, in 1910, 3 miles south of Winchester, Ind. URBAN AND RURAL POPULATION The Census Bureau classifies as urban population that residing in cities and other incorporated places of 2,500 inhabitants or more, includ- sidered as rural. In 1880, of a total population in the United States of 50,155,783, there were in municipalities 14,772,438, or 29.5 per cent of the population. In 1890, this element had grown to 22,720,223, or 36.1 per cent of the total population; in 1900, it was 30,797,185, or 40.5 per cent ; and in 1910, 42,623,383, or 46.3 per cent of the total population of the United States. From 1900 to 1910 the rate of increase for the population of urban areas was over three times that for the population living in rural territory, the rates of increase being 34.8 and 11.2 per cent respectively. There were 14 States in 1910 in which more than half the population was living in territory classed as urban. The greatest per cent urban in any State was Rhode Island, which had 96.7 per cent, while North Dakota, with 11 per cent, had the smallest proportion of its people in urban communities. 1900 and 1910 an increase in urban population, but in six States — New Hampshire, Vermont, Ohio, Indiana, Iowa and Missouri— there was a decrease in rural population. In all but two States — Montana and Wyoming— the urban population in- PARENTAGE Of the population of the United States in 1910, 81,731,957, or 88.9 per cent, were whites; 9,827,763, or 10.7 per cent, were negroes; and 412,546, or four-tenths of one per cent, were other colored races, including Indians, Chinese, Japanese, Hindus, Koreans, and others. Of the total population, 78,456,380, or 85.3 per cent, were native and 13,515,886, or 14.7 per cent, foreign born, the latter consisting chiefly of whites. The native white population numbered 68,386,412, and constituted 83.7 per cent of the white population and 74.4 per cent of the total population of the country. The 13,345,545 foreign-born whites consti- tage in 1910 numbered 49,488,575, constituting 60.5 per cent of the white population and 53.8 per cent of the total population. Native whites of foreign parentage formed 15.8 per cent of the white population and those of mixed parentage 7.3 per cent, the corresponding percentages based on the total population being 14 and 6.5, respectively. crease of the white population. The native white population increased 20.8 per cent and the foreign-born white 30.7 per cent. The increase of negroes and Indians, since their numbers is only slightly affected by immigration, or emigration, is essentially a natural increase. Of the 9,827,763 negroes enumerated in 1910, 7,777,077 were returned as black and 2,050,686 as mulatto, or 20.9 per cent. In 1850 the per- PER CENT OF NEGEOES IN TOTAL POPULATION, BY STATES Of the total increase of 15,977,691 In the population of the country between 1900 and 1910, the whites contributed 14,922,761, the negroes 993,769, - and other races 61,161. The increase in the native population was 12,803,081, and that in the foreign-born, 3,174,610, or about onefifth of the total increase. The percentage of increase for the whites, 22.3, was a little less than twice as high as that for the negroes, 11.2. This difference is partly due, however, to the direct or indirect effect of immigration upon the in- centage of mulattoes was 11.2. It had advanced but little in 1870, being only 12 per cent, but since 1870 the proportion of mulattoes in the total negro population appears to have increased materially, reaching 15.2 per cent in 1890, and, as given above, 20.9 per cent in 1910. POPULATION Since 1890, the first census to include an enumeration of Indians in Indian territory and on Indian reservations, the Indian population has DISTRIBUTION OF THE INDIAN POPULATION OF THE UNITED STATES, BY STATES increased slightly, being 248,253 in 1890 and 265,683 in 1910. During the same period the Chinese population decreased from 107,488 in 1890 to 71,531 in 1910, while the Japanese population increased from 2,039 in 1890 to 72,157 in 1910. There were also enumerated in 1910 other non-white races, consisting, for the greater part, of Hindus and Koreans, to the number of 3,175. PRINCIPAL CITIES It may be of interest to consider the population of principal cities with respect to color, nativity and parentage. In only fourteen of the fifty cities having a population of over 100,000 did native whites of native parentage constitute as much as one-half of the total population. The proportion exceeded three-fifths in only fout cities, Indianapolis, 64.5 per cent; Columbus, 64.4 per cent; Dayton, 62 per cent, and Kansas City, 61.9 per cent. On the other hand, in twenty-two of the cities of this class, less than one-third of the population were native whites of native parentage, over two-thirds in all but one of these cities consisting of foreign-born whites and their children. In Fall River only 13.3 per cent of the population were native whites of native parentage. In 10 cities of 100,000 inhabitants, or over, the population was more than one-third foreign-born white, namely, Fall River, 42.6 per cent; Lowell, 40.9 per cent; New York, 40.4 per cent; Paterson, 36.1 percent; Boston, 35.9 per cent; Chicago, 35.7 per cent ; Bridgeport, 35.5 per cent; Cleveland, 34.9 per cent; Providence, 34 per cent; and Detroit, 33.6 per cent. ern cities. Among the northern cities it was lowest in Indianapolis (8.5 per cent) and Columbus (9 per cent). In many of the fifty cities having a population of over 100,000 the proportion of native whites of foreign or mixed parentage was nearly the same as the proportion of foreign-born whites. The native whites of foreign or mixed parentage were relatively most numerous in Milwaukee (48.8 per cent) and Fall River (43.7 per cent). 79,066 foreign-born white population in New York City advanced from 1,260,918 to 1,927,703, ait increase of 666,785, while native volutes of native parentage increased only 183,841. In 1910 only 19.3 per cent of the city's population consisted of native whites of native parentage. Of the total population of the United States approximately one-twentieth is domiciled in New York City; of the native whites of native paren- tage, one-fiftieth ; of the native whites of foreign or mixed parentage, one-tenth ; and of the foreignborn, one-seventh. Among the larger cities the proportion of negroes in 1910 was highest in Memphis, 40 per cent, followed by Birmingham, with 39.4 per cent; Richmond, 36.6 per cent; Atlanta, 33.5 per cent; Nashville, 33.1 per cent; Washington, 28.5 per cent; New Orleans, 26.3 per cent; Louis- ville, 18.1 per cent ; and Baltimore, 15.2 per cent. In no other city of over 100,000 inhabitants did the negro element amount to one-tenth of the population. Classified according to numbers, the following cities returned more than 50,000 negroes in 1910: Washington, 94.446; NewYork, 91,709; New Orleans, 89,262; Baltimore, 84,749; Philadelphia, 84,459; Memphis, 52,441; Birmingham, 52,305; and Atlanta, 51,902. CLASSIFICATION OF POPULATION BY SEX There were in the United States in 1910, 47,332,277 males and 44,639,989 females, or 106 males to each 100 females. The excess of males in the United States is partly due to extensive immigration, a much larger proportion of the immigrants being males than females. In the native white population of the United States, however, there is also an excess of males over females, the ratio in 1910 being 102.7 males to each 100 females. Persons 21 years of age and over have certain special legal rights with reference to property, the elective franchise, and other matters. This class of the population is further significant from the social and economic standpoint, in that it includes the great majority of breadwinners and also the great majority of married men and women. From the political standpoint particular interest attaches to statistics regarding males 21 years of age and over, although in several States women of that age also now have the right to vote at all elections. For the United States, exclusive of Alaska, Hawaii, Porto Rico, and other outlying possessions, the total population 21 years of age and over in 1910 was 51,554,905, representing 56.1 per cent of the total population of all ages. Of this number. 26,999,151, or 29.4 per cent of the total population, were males, and 24,555,754 were females. MALES OF MILITIA AGE Men' from 18 to 44 years of age, inclusive, are subject to militia duty under the laws of most States, and represent substantially the theoretical fighting strength of the country in case of war. The total number of males from 18 to 44 years of age in 1910 was 20,473,684, representing 22.3 per cent of the total population of the country and 43.3 per cent of the total male population. Immigration into the United States has experienced a marked reduction as a result of the European war, dropping from a total of 1,218,480 for the year ended June 30, 1914, to 326,700, and 298,826 for the years ended June 30, 1915 and 1916, respectively. This falling off is not of a temporary nature, but is certain to continue for many years, even after the close of the war. admitted during the year ended June 30, 1916, 9,795 had been engaged in the professions, 45,528 were skilled laborers, 138,737 had been engaged in miscellaneous occupations, and 104,766 (including the women and children) reported no occupation. Of the 129,765 emigrant aliens departed, 2,097 had been engaged in the professions, 13,874 were skilled laborers, 96,405 had been engaged in miscellaneous occupations and 17,389 (including the women and children) reported no occupation. Eighteen thousand eight hundred and sixty-seven persons were debarred during the year. Of this number, 10,383 were debarred as being likely to become public charges, 1,153 as having a loathsome or dangerous contagious disease, 1,657 as of mental defects (other than idiots, imbeciles and insane) and 2,080 as being contract laborers. There -were 2,906 persons deported after landing, of which number 1,081 were deported because of the possibility of becoming public charges, 282 for insanity, 360 for having entered without inspection, 114 as criminals and 100 for loathsome or dangerous diseases. 298,826 eluding Alaska, Hawaii, I'orto Rico, and the military and naval stations abroad. The gainful workers thus formed 41.5 per cent of the total population. In continental United States the gainful workers numbered 38,167,336, which was 41.5 per cent of the the males ten years of age an.d over. In the female population the gainful workers numbered 8,075,772, which was 23.4 per cent of all females ten years of age and over. Thus, in the population ten years of age and over, more than one-half of all persons, over four-fifths of t&e males, but were gainfully occupied. In the States the proportion of the population ten years of age and over engaged in gainful occupations in 1910 ranged from 46.9 per cent in Iowa to 68 per cent in Mississippi. The States having the smallest proportions were : Iowa, 46.9 per cent ; Kansas, 47 per cent; Nebraska, 47.7 per cent; Utah, 47.9 per cent; and Indiana 48 per cent. The States having the largest proportion were North Carolina, 60 per cent; Georgia, 61.5 per cent ; Wyoming, 62.6 per cent ; Nevada, 64.3 .per cent ; Alabama, 64.7 per cent ; South Caro- lina, 67.6 per cent; and Mississippi, 68.7 per cent. Except in three States — Arizona, Montana and North Dakota— 'there was an increase, from 1900 to 1910, in the proportion of the population ten years of age and over engaged in gainful occupations. The States showing the largest increases were Alabama, Arkansas, Georgia, Mississippi, Nevada, North Carolina, South Carolina and Texas. turned from the registration area of the United States for the year 1914 was 898,059. The estimated mid- Agriculture, forestry, and animal husbandry Extraction of minerals (mining and quarrying) Manufacturing and mechanical industries Transportation total population of the United States. The death rate for the year was 13.6 per one thousand population, the lowest on record since the establishment of the registration area in 1880, being 19.8 in 1880, 19.6 in 1890, 17.G in 1900, 16.0 in 1905, 15.0 in 1910 and 14.1 in 1913. The deaths among the white population numbered 824,319, or 917.9 for every thousand deaths. Of this number, 605,349 were native born ; 327,696 had both parents native; 203,189 had one or both parents foreign born ; and 74,464 of unknown parentage. Other deaths among the white population were 207,272 foreign born, and 11,698 unknown. The deaths among the colored population, numbering 73,740, or 82.1 for every thousand deaths, were divided as follows: Negro, 70,429; Chinese, 1,018; Japanese, 904; Indian, 1,369; and other colored, 20. Of the total number of deaths 491,416 were males, and 406,643 were females. The total number of deaths among children less than one year of age was 155,075; of those from one to five years of age, 58,045 ; from five to twenty-five, 86,355; from twenty-five to fifty, 196,087; from fifty to seventy-five, 217,207; over seventy-five, 123,963, of which 467 were one hundred years of age or over ; and of ages unknown, 1,327. Out of every thousand deaths 172.7 occurred before the end of the first year of life ; 96.2 between the ages of five and twenty-five; 218.5 between the ages of twentyfive and fifty; 307.6 between the ages of fifty and seventy -five; and 138.0 over seventy-five years of age. The number of deaths in the registration area during 1914 from various causes were as follows: Typhoid fever, 10,188; malaria, 1,477; smallpox, 212; measles, 4,461; scarlet fever, 4,340; whooping cough, 6,816; diphtheria and croup, 11,786; influenza, 6,014; other epidemic diseases, 6,125; tuberculosis, 96,903; cancer, 52,420; diabetes, 10,666; diseases of the nervous system and organs of special sense, 87,614 ; diseases of the circulatory system, 123,901 ; diseases of the respiratory system, 104,086; diseases of the digestive system, 99,673; non-venereal diseases of the genito-urinary system, 78,023; suicide, 10,933; homicide, 4,847; and other external causes, 51,770. causes was as follows: Typhoid fever, 15.4 ; malaria, 2.2 ; measles, 6.8; scarlet fever, 6.6; whooping cough, 10.3 ; diphtheria and croup, 17.9 ; influenza, 9.1 ; tuberculosis, 146.8; cancer, 79.4; diabetes, 16.2; diseases of the nervous system and organs of special sense, 132.8; diseases of the circulatory system, 187.8; diseases of the respiratory system, 157.7; diseases of the digestive system, 151.0; non- venereal diseases of the genito-urinary system, 118.2; suicide, 16.6; homicide, 7.3, and other external violence, 78.5. makes the same impression. Such a number measures the dollars which value the agricultural production of the United States in a year. To say that the total estimated value of all crops and animal products for the year ending June enough, working every minute of every day and every night, to make out deposit slips to put it in a bank in a year's time. It represents a hundred dollars for every man, woman and child in the country. If the cost of the Panama Canal is $500,000,000, one year's crops would build twenty such canals ! If it costs Europe $20,000,000 a day ' to have a war, then we could finance If a man could keep awake twenty-four hours in a day, and could live for a hundred years under such conditions, he would have to SIKMH! during every waking minute of his life something more than $199 to dispose of this sum in .the hundred years. AGRICULTURAL INFORMATION It is, of course, an impossibility to do more than indicate the extent of agriculture or its immense importance not only to the United States but to the world. Those who wish particular facts of any special subject can obtain Volume V. of the Census of 1910, which gives figures for 1909 in 927 closely printed pages, many tables and graphic drawings, or the Year Book of the Department of Agriculture, which has a number of "graphs" as well as 174 pages of finely printed statistics. Best of all, however, for the man interested in some one special phase of this question is the opportunity afforded him by correspondence with the Department of Agriculture. Inquiries on any subject connected with agriculture receive prompt attention in Uncle Sam's greatest department and information to answer any inquiry is either on hand or will be obtained for any inquirer. GENERAL STATISTICS The total area of the United States is 1,903,269,000 acres. Of this 46.2 per cent is productive land ; that is, land which is capable of being turned into farm, grazing or tillable area, exclusive of any possible future engineering developments in the reclamation field which may make vast areas, now arid, agricultural possibilities. Of this 46.2 per cent of productive land, 293,794,000 acres (1910 census figures, latest available), representing 15.4 per cent of the total area, are under cultivation. Thirty-six of the principal agricultural countries of the world have 30.5 per cent of their total area possibly productive and but 8.7 of their total area under production. With a ratio of approximately one to four for tke world, then, the United States has approximately one to three (one-third) of its agricultural possibilities developed. UNITED STATES The United States, in spite of its showing in area and its leadership of the world in the world's principal crops, can by no means be considered to have even begun to realize its agricultural possibilities. It can triple its area under cultivation with the same methods and the same productiveness and still fall far behind the averages of other countries which have been compelled to make intensive agriculture a wheat field. The 1910 census gave 10,582,000 males as actively engaged in agriculture in the United States, 35.2 per cent of males engaged in all occupations. Females engaged in agriculture to the number of 1,806,584, 22.4 per cent of all women engaged in all occupations. This makes a total of 12,388,623 people engaged in agriculture, or 32.5 per cent of the people engaged in all occupations. Compare with the following countries (percentages from most recent figures obtainable) : Of the total population there are engaged in agriculture in Argentina 23.6 per cent, Australia 25.6 per cent, Austria-Hungary (pre-war) 63 per cent, British India 67.1 per cent, Canada 39.9 per cent, France (prewar) 42.4 per cent, Germany (prewar) 34.6 per cent, Italy (pre-war) 58.8 per cent, the Philippines 41.3 per cent, Spain 56.9 per cent, Sweden 52.8 per cent, Union of South Africa 65.1 per cent, United Kingdom 12.4 per cent. CANADA With these figures in mind, and not forgetting the possibilities of intensive cultivation, which, as shown in the following statistics for several commodities, is practiced abroad so effectively as greatly to increase the yield per acre over United States figures, it is obvious that the limit of agricultural development in this country is so far distant that no man can foresee it. Eliminating all possibilities of increase of tillable area through irrigation, and all possibilities of increase of yield through modern scientific development, not this nor many future generations will see the ability of this land ' to support its population from an agricultural standpoint reached or passed. GROWTH The more than double doubling of farm products within one generation is a sure indication of the wonderful growth of the United States. Pages might be written about it, but could do no more than show what the table on page 38 expresses so vividly. wheat production 1915 was the record for the United States, greater than any previous year by 128,000,000 bushels. Exports of wheat and wheat flour jumped from $142,000,000 in 1914 to $428,000,000 in 1915, a proportion which is considerably less than the jump in corn, which with corn meal was from $7,000,000 to over $39,000,000. Neither crop, however, compares in its export jump with oats. In 1914 the United States exported $1,000,000 worth and in 1915 $57,000,000 worth. It is hardly necessary to chronicle, because every one knows that the immense increase in exports of food stuffs as well as manufactures changed the status of the balance of trade for this country. It is also well known how the export of cotton decreased, the figures being from $610,000,000 to $376,000,000 in a year. the war has had on the whole a very beneficial effect upon American agriculture. Exports of wheat and wheat flour represented over 37 per cent of the 1914 crop, while the usual exportation is less than 20 per cent. Farmers received an average of 79 cents per bushel for the 1913 wheat crop and $1.01 for the crop of 1914, an increase of 32 cents per bushel or an aggregate gain of approximately $196,000,000. Because of the vastness of the subject it is impossible to do more than indicate here the value and extent of a few of the principal crops of the United States. Unless otherwise stated, statistics given are for 1915 and prices are values at the farm. duces more wheat than any other country, and a great deal more than we use, many people think wheat is our principal crop. Such is not the case, corn being the principal crop of the United States. One hundred and eight million three hundred and twenty-one thousand acres in the United States are under cultivation for the corn crop of 3,054,535,000 bushels. As the production for all of North America, including Canada, United States and Mexico; Argentina, Chile and Uruguay in South America ; AustriaHungary, Bulgaria, France, Italy, Portugal and Roumania, Russia, Servia, Spain, India (both British and native states), Japan, the Philippine Islands, Algeria, Egypt and Union of South Africa, Australia and New Zealand, was but 3,864,279,000 bushels in 1914, it is easily understood why the United States is the greatest corn producing country in the world. Argentina, with 10,386,000 acres under corn cultivation, is next in productive ability, but her total crop for 1915 was but 338,000,235 bushels. World production of wheat is 4,216,806,000 bushels. Of this the United States produces 1,011,505,000 bushels, more than is grown even in Russia, the yield of which is estimated to be 833,965,000 bushels. In the United States 59,898,000 acres are under cultivation for wheat, an increase of over 9,000,000 acres in the past two years. A remarkable fact in connection with the world's wheat production is that Germany, which produces but 160,000,000 bushels of wheat in a year, has, by an average of statistics for ten years, a yield of 30.7 bushels to the acre, whereas the average for the same period in the United States is but 14.8 bushels. Hungary has an average of 18.1 bushels, France 20.1 and the United Kingdom 33.4 bushels. Either land abroad is more productive or methods of farming are more intensive ; nevertheless the United States easily leads the world in producing the raw material for the staff of life. TAKING ON A CAEGO OF WHEAT ber 1st, the value of this wheat crop is $930,302,000. Wheat is produced in every State in the Union, although Massachusetts, New Hampshire, Rhode Island, Connecticut, Florida and Louisiana produce but little. North Dakota is the greatest wheat producing Sate, yielding 151,970,000 bushels, followed by Kansas with 106,538,000 bushels. greater than the smallest year (1911) yield average of I2y2 bushels per acre. The 1915 yield per acre was almost 2 bushels an acre greater than the average for the 10 years from 1906 to 1916, which was exactly 15 bushels to the acre for the whole United States. It is also interesting and a little puzzling to learn that the greatest yield of wheat per acre comes from Vermont, not known as a wheat producing State, but the few wheat farms of which give an average of 30 bushels to the acre. The poorest wheat producing State in yield per acre is Tennessee with 10%, followed by South Carolina with 10.8 bushels per acre. Forty million seven hundred and eighty thousand acres of farm l?nd are under cultivation for oats, producing 1,540,362,000 bushels. The world's production is estimated to be in excess of 4,700,000,000 bushels. Russia produces the second largest amount with 1,006,983,000 bushels, followed by Germany with 650,000.000 bushels. The United States falls far below other countries in the average yield of oats per acre. The average yield in the United States from 1905 to 1914 was 29.5 bushels per acre. In the same period Germany produced 54, Hungary 31.5, France 31.1 and the United Kingdom 43.5 bushels of oats per acre. The total value of the oats produced in the United States in 1915 was $555,569,000. Barley Unspectacular, because comparatively little known, is the barley crop, yet the United States has 7,395,000 acres devoted to its production, resulting in 237,009,000 bushels. Barley is much more largely grown and highly thought of abroad than here. World production is 1,542,972,000 bushels, of which Russia produces 475,109,000 bushels, almost double that of the United States. The value of the 2,856,000 acres, a small fraction of the world's production of 1,711,158,000 bushels. Any farm product in the United States worth less than $50,000,000 for the year is to be considered among the comparatively unimportant products. Similarly buckwheat, of which 806,000 acres produce 15,769,000 bushels at a value of $12,408,000, comes among the unimportant crops, yet buckwheat, used as it is largely for a breakfast food, is increasing in popularity in the United States. The value of the product ten years ago was but $8,565,000; twenty agricultural products of the United States, potatoes are among the most commercially important. They afford one of the most nutritious and one of the cheapest foods for the table of rich and poor alike. A failure in the potato crop means disaster. Three million seven hundred and sixty-one thousand acres are devoted in the United States exclusively to the production of potatoes. The production is 359,103,000 bushels, a large increase in the past ten years, the 1905 figures being 260,741,000 bushels. The average farm price per bushel is 61.6 cents, or a total value for the whole crop of $221,104,000. Potatoes are among the most universally grown crops in the United States, every State producing enough to make a variation in the statistics if omitted. Even little Rhode Island has over 5,000 acres devoted to the production of the popular "spud," growing 550,000 bushels. Maine and New York are the two largest producers of potatoes, both accounting for 22,010,000 bushels. The value of the New York crop is about $3,000,000 greater than that of the Maine crop, although Maine produces its crop from 142,000 acres, whereas New York has 355,000 acres engaged in potato production. The production of potatoes abroad makes a curious comparison with that of the United States. The world production is 5,714,188,000 bushels (1913 figures). Of this enormous total Austria-Hungary alone produced 627,728,000, one third more bushels than produced and used by the United States in 1915. Germany by it he sustains his working tools, the farm animals, and feeds the stock, which is in itself a crop. In the United States 50,872,000 acres produce hay with an average yield of 1.68 tons per acre. This makes the total production 85,225,000 tons, a weight as impossible to realize as it is to grasp the fact that it is valued at $912,320,000. The combined navies of the world have not a tonnage equal to the United States hay crop. A fleet of two thousand boats, each the size and dimensions produces 1,674,377,000 bushels of potatoes, whereas the total for European Russia is 1,269,696,000 bushels. It is amusing to note that of the 279,121,000 bushels produced by the United Kingdom in 1914, Scotland grew 40,270,000, Wales 5,445,000, England 104,504,000 and Ireland the balance of 128,642,000 bushels of Irish "praties." wheeled vehicles enough in the United States, outside of railroad equipment, to load a year's crop upon it and haul it to market in one day's time. New York and Pennsylvania are the two leading States, the former growing 5,850,000 tons on 4,500,000 acres, valued at $91,845,000, and the latter growing 4,340,000 tons on 3,100,000 acres, valued at $67,704,000. Rhode Island produced the least amount of hay, No crops are more important to manufacturing than cotton. Most agricultural products either feed the world or the animals which, working for farmers, assist in feeding the world. Cotton and wool, however, are agricultural products which are used for clothing, and cotton, much more than wool, is of enormous importance in the arts. The war conditions hurt the cotton industry in this country to a very large extent, but a recovery is now under way, and even though the war continues it will in time grow nearly to normal. Under usual conditions over 65 per cent of the cotton crop of the United States is exported, 53 per cent of our total agricultural exports consisting of cotton. Consequently anything which hurts its exportation strikes a blow at the whole cotton industry of the United States, much as if over half of our wheat crop or half of our farm animals should suddenly be wiped out of existence. On the 1st of August, 1914, cotton sold at an average of 12.4 cents a pound. By November it had declined to 6.3 cents a pound, a reduction of nearly one half. The whole cotton crop of 1913 averaged to its producers 124 cents per pound, whereas that of 1914 averaged but 7.3 cents, a decline of over 40 per cent. In other words, over $283,000,000, or one-third of the estimated value of the cotton crop, was lost on account of the war, and this in spite of the fact that production in 1914 was almost 2,000,000 bales greater than in 1913. It is difficult for the uninitiated to appreciate the extent to which the South depends upon its cotton product. Cotton and cotton seed represent almost two thirds of the value of all crops produced in Georgia and Mississippi. Cotton represents 63 per cent of the value of aL crops produced in Texas, 60 per cent of those produced in Ala- duced in Arkansas. The industrial depression caused by the shrinkage in cotton values was severe, but by June, 1915, the total shipments for the year were within 8 per cent of the preceding year. Nevertheless the value has shrunk, in spite of crop recovery, over 38 per cent. As a result of this, plus the foreign demand for grain, the acreage under cultivation for wheat, barley, oats and other cereals needed abroad has greatly increased, while cotton planters now plant a much smaller acreage than in prewar times. The estimate for the cotton crop for the fiscal year is MECHANICAL COTTON PICKER less than 11,000,000 bales, which, compared with the production of 16,134,000 bales in 1914 and with an average yearly production in the preceding five years of 13,033,000 bales, is rather small. The decrease results from a reduction of about 15 per cent in the acreage planted in cotton and a 20 per cent poorer yield. Few countries give official statistics for the production of cotton, so that to state any figure and call it the world's production of cotton is impossible with any degree of accuracy. British India produced 4,238,494 bales of cotton in 1914 against over 16,000,000 for the United States for the same year. The total for Russia in 1914 was 1,177,995 bales and Egypt is credited with 1,450,000 bales during the same period. Statistics of 1910 give the world's production of 22,433,269 bales of cotton, but are frankly inaccurate and are only for those comparatively few countries from which figures are available. Normally the United States has under cultivation in the neighborhood of 36,000,000 acres of cotton and could normally expect this year to produce a much larger quantity than will be picked under the abnormal conditions. Texas is the largest producer of cotton among the States, accounting for 3,175,000 bales of 500 pounds each. Georgia is next with 1,900,000 bales, followed by South Carolina with 1,160,000 bales. Virginia has the smallest cotton crop, marketing but 16,000 bales. produced 199,753,000 pounds of tobacco. In 1915 our production was 1,060,587,000 pounds, a crop valued at $96,041,000 at the farms of 1,368,400 acres which produced it. Kentucky is the leading tobacco State, with 356,400,000 pounds yearly, followed by North Carolina with 198,400,000 and Virgina with 144,375,000 pounds. tural products which we both export and import, the imports, however, falling far short of the exports. In 1914 our exports were 348,346,091 pounds (more than 40 per cent of the crop) and our imports 45,764,728 pounds. The reason for any imports, of course, is the fact that there are so many varieties of tobacco, and not all kinds grow well, or in sufficient quantity, in the climate of our Southern States. Both exports and imports given above are of the unmanufactured tobacco. are not available with any degree of accuracy since 1911, when the total was 2,566,202,000 pounds, not quite three times the production of the United States alone in that year. One million three hundred and sixty-seven thousand acres produce 13,845,000 bushels of flax and flax seed, of which the average farm price per bushel is $1.739. The total value is thus $24,080,000. North Dakota leads all flax producing States with an acreage of 660,000 and a production of 6,534,000 bushels, and as the value of this North Dakota flax was over $11,000,000 this one State has nearly half the flax industry of the United States. Rice is not one of the great crops of the United States and yet an acreage of 803,000 is devoted to its growing. Twenty-eight million nine hundred and forty-seven bushels of rice, with a value of $26,212,000, is the rice industry's contribution to our agricultural wealth. For comparison with statistics of other countries it is necessary to express production in pounds. In 1914 we grew 656,917,000 pounds, while Italy produced 741,263,000 pounds and British India 62.638.912,000 pounds. Japan grew 17,827,247,000 pounds and our own Philippine Islands 1,403,516,000 pounds. Just what a small proportion of the total rice crop of the world is ours is shown by the Apples are among the important fruit crops of the United States. Of three bushel barrels there were 76,670,000 grown, at an average price of 74.6 cents per bushel at the farm. The principal apple producing State is New York, with 8,528,000 barrels, followed by Missouri with 6,287,000 barrels and Pennsylvania with 5,085,000 barrels. There are more than 35 varieties of apples extensively grown in the United States, of which the most popular is the Baldwin, with 13.4 per cent of the total crop; followed by Ben Davis, 13.3 per cent ; Northern Spy, 6.1 per cent; Winesap, 5.1 per cent; Rhode Island Greening, 4.7 per cent, and Jonathan, with 3.6 per cent of the total crop. The total production of apples in the United States was considerably less in 1915 than in 1914, the difference being over 8,000,000 barrels, which is almost exactly the difference between the production in 1914 and 1915 in New York State. United States orchards produce 64,218,000 bushels of peaches. The farm price per bushel averages 81.1 cents, making the total peach crop of the United States $52,080,798 in value. California leads in the peach production with 9,768,000 bushels, followed by Arkansas with 5,940,000 and Georgia with 5,330,000 bushels. principal hop producing countries of the world grew 173,937,000 pounds of hops. Of this quantity the United States produced 62,898,000 pounds. The following year, 1914, the hop production in the United States dropped to 43,415,000 pounds. As might be expected, Germany, if not the leader, is very close to the front in the production of this herb, being responsible (1914) for 55,227,000 pounds. The United Kingdom bean crop is enormous, but available statistics are too scattering, even in the largest bean producing countries, to have any great degree of accuracy. The United States has no official figures for beans later than 1912, which were issued by the census office. In that year 11,145,000 bushels of beans were grown. Austria-Hungary beats this production by almost 50 per cent, growing 20,445,000 bushels ; France produces 9,354,000 bushels (1914), Italy 16,997,000 (1914) and European Russia 12,717,000 (1913) bushels. The price of beans in the United States in 1915 fluctuated between $2.15 and $6.40 per bushel. area devoted to the production of peas in the United States. There are no later official figures. The 1912 production was 7,110,000 bush- FIELD OF SUGAR BEETS els, comparing not at all with European Russia, which in the same year produced 32,128,000 bushels, or even with Spain, which produced 9,885,000 bushels, although the Spanish figures for peas include chick peas, lentils and vetches. Sugar beets and sugar cane form a very important industry in the United States, there being 67 factories engaged in the production of beet sugar from beets. These factories produce 862,800 short tons of sugar, chiefly refined. Six hundred and twenty-four thousand acres are devoted to the production of sugar beets, each acre yielding an average of 10.4 short tons of beets, so the total devoted to beets was 5,502,200 acres (1913). It is, therefore, not surprising to note that Europe's production of sugar from beets in 1913 was 61,774,400 tons against the five and one half million of the United States. Louisiana is the cane sugar center. In 1914, the last year for which statistics are available, 149 factories produced 242,700 short tons of sugar from SMUDGE POTS that 6,462,000 tons were utilized. Sugar beets average $5.54 per ton. The principal refineries are located in California (11), Colorado (14), Idaho (4), Michigan (15), Ohio (4) and Utah (8). The United States is by no means the world leader in beet sugar, Austria-Hungary producing over 1,700,000 and Germany 2,755,750 short tons. In the United States, according to 1914 figures, a total of Is:;,400 acres were devoted to growing 3,199,000 short tons of sugar cane. The average yield of cane per acre in Louisiana was 15 tons, a loss of two tons from the unusually luxuriant production in 1913, 17 tons to the acre. The Hawaiian Islands have 46 factories, which average 183 days operation in the year. In 1914 the Hawaiian factories produced 612,OuO short tons of sugar from the harvest of 112,700 acres. OO production of 4,900,000 short tons of cane. The Hawaiian cane is extremely rich, requiring but a single short ton of cane to produce 250 pounds of sugar, an average yield of 10,861 pounds of sugar per acre of cane. Horses and Mules Increase in numbers of horses and mules on United States farms has fully kept pace with the increase in population. The census of 1870 415 mules in the United States. The estimated number for 1916, based on the best available statistics, is 21,166,000 horses and 4,565,000 mules. The average value of a farm horse in 1S70 was $67.43. To-day it is $101.60. The average price of a drafter, $483 for a carriage team, $169 for drivers, $160 for general horses, $184 for saddle horses, and so on. These figures represent a con- 133,264,000 farm mule in 1870 was $90.42. Today it is $113.87. The total valuo of all horses in 1870 was $556.251.000. To-day it is $2. 1.10. Kix.oon. Mules were valued in 1870 at $106,654,000. To-day their value runs in excess of $519,820,000. modity for the whole United States is seldom equal to the market price as paid in any of the great markets. siderable increase in recent years, Chicago prices for 1901 being $157 for drafters, $400 for carriage team, $137 for drivers, $102 for horses for general work and $147 for saddle horses. Iowa farms possess more horses than any other State, having 1,584,000. Illinois comes next with 1,452,000, then Texas with 1,180,000, with Kansas, Montana and Nebraska AGRICULTURE next, all having more than 1,000,000. Texas easily leads in the possession of mules with 753,000. Montana follows with 329,000 and Georgia has 309,000. Texas, of course, is the great cattle State. Nineteen sixteen figures give the Lone Star ranges 1,119,000 milch cows and 5,428,000 other cattle. Iowa follows with 1,391,000 milch cows and 2,737,000 other cattle. Illinois, Wisconsin aud Minnesota are all among the greatest cattle States, the stock on farms outnumbering even the great herds in more strictly cattle States, such as Oklahoma is popularly supposed to be with its 1,638,000 head. Sheep, like cattle, are valued not only for their meat but for wool and hide. United States sheep total 49,162,000. The average price per head is $5.17, making the total farm value $254,348,000 for all the sheep in the United States. Wyoming, the great sheep State, leads with a herd of 4,338,000, followed by Montana with 3,941.000, New Mexico with 3,440,000, Idaho with 3,102,000 and Ohio with 3,067,000. While this enormous herd roams the Western -plains and Eastern farms 36,000,698 fleeces are marketed, the average weight of which is 6.78 pounds, the total product in the raw state being 228,777,000 pounds of wool. Farms of the United States possess a herd of 68,047,000 swine, the average price of which is $8.40 per head, or a total farm value of $571,890,000 for pork alone. Iowa is the great pork State of the Union, averaging in 1916, 9,069,000 hogs and pigs of all kinds, followed by Missouri, Illinois, Nebraska and Indiana, all over 4,000,000 each. The space at hand forbids an extension of this brief survey of a part of the agricultural wealth of the United States. Perhaps no one set of figures can show in more succinct manner the extent of the farm.ing activities of this country than the table on page 62 of our agricultural products carried on railroads and therefore marketed. States Census dealing with the fishing industries of the United States is that of 1908. The next report will be in 1918. The 1908 figures, given below, are therefore only authoritative in giving a comparison between the various piscatorial products of our waters and cannot be accepted too literally even there, as the past eight years have seen many changes in some of the industries. ture, but detailed figures of certain other fish industries are available through the work of the Bureau of Fisheries. The greatest fishing industry of the Atlantic Coast is conducted by the fleets centering at Boston and Gloucester. Three hundred and HALIBUT FISHERMAN The most important sea food industry in the United States is unquestionably the oyster industry. No product of the water has a greater nutritive value and none is more readily caught and sold than this shell fish. No statistics, however, later than those of the census of 1908 are available for oyster cul- 162,589,220 pounds of fish, valued at $4,395,030. This shows a decrease in the number of trips from the previous year of 1,231, an increase in the catch of 372,434 pounds, but a decrease in the value of $587,987. 26.000 The total quantity and value of the products of the fisheries of the United States including the items mentioned above and all other fish products was 1,893,454,000 pounds, valued at $54,031,000. No later figures are available at time of publication. In many cases there dock were landed, valued at $1,381,156. This was an increase in the number of pounds landed during the previous year by over four million, but a decrease of $100,000 in value. Pollock fish, which are caught with purse seines, yielded a less number of pounds and value in 1914than 1913, the 1914 catch being 12,454,723 pounds, valued at $199,736. SWORDFISH Swordfish were less plentiful in 1914 than several years previously. American fishing vessels landed at Boston and Gloucester in 1914 Cod is among the most important fish; it is marketed both fresh and salt, and as cod and scrod, the latter being from one to two and one half pounds in weight. The total catch of all kinds landed at Boston and Gloucester was, in 1914, fresh cod, 36,079,873 pounds, valued at $917,908; salted cod, 11,449,757 pounds, valued at $411,508. Newfoundland herring landed at Boston, Gloucester and other New England ports during the season of 1914 and the first part of 1915 amounted approximately to 2,570,352 pounds of fresh frozen fish, and 49.166 barrels, amounting to 11,071,584 pounds, of salted herring. 3,063,000 pounds, and salted halibut to the amount of 316,000 pounds, valued at $30,000, was packed during the year. Hake was caught to the amount of 7,404.335 pounds, valued at $146,030, and salted to the amount of 222,033 pounds, valued at $4,218. LOBSTERS Lobsters are caught from Lewes, Del., to the tip of Maine, and provide 12,267,017 pounds of sea food annually (1913), valued at $2,394,822 for 8,832,281 lobsters. The industry shows the peculiar and anomalous condition of a steadily decreasing output and a steadily increasing profit to those engaged. In twenty-four years' time the yearly catch has decreased by more than 18.000,000 pounds, or 00 per cent, while the fisherman's receipts have increased by a million and a half dollars, or 178 per cent. In 1880 the lobster brought an average of .024 cents a pound. In 1913 lobsters averaged .191 cents per pound, nearly ten times as much as in 1880 and two and a half times as much as in 1900. The 1914 season saw the Alaska fishing industry at its height of value. It afforded employment to 21,200 persons and included the investment of $37,000,000. The total value of the products of the Alaskan fishers is estimated at $21,2<3,OuO, an advance of over $5,500,OuO over 1913, due largely to an unusual abundance of red salmon and the higher prices commanded by canned salmon. condition of the seal herd. A complete census of the seals shows 294,687, an increase of nearly 27,000 animals over the year 1913. The 1915 census has not yet been completed but indicates an increase of 60,000 animals over 1914. MUSSEL The Bureau of Fisheries has been conducting a general canvass of fresh-water mussel fishing, which has been in progress for several with supervision of propagation and distribution of food and game fishes and scientific investigations into all matters pertaining to fish. In 1914 the enormous quantity of 4,288,757,800 fish and ova were distributed. The greater proportion of this, of course, was egg and not fish, but fingerling. yearling and adult fish numbered over 58,000,000, an increase of 150 per cent over 1914. Of this number, salmon, trout and bass contributed the larger part. VILLE, VA. years on the streams inland. The canvass covered in 1914 included tributaries to the Great Lakes and the Ohio and Mississippi Rivers. Three thousand nine hundred and fifty-two persons were engaged in taking mussels in the streams under consideration and in preparing them for the market. The mussel fisheries had an output of 23,317 tons of shells, valued at $382,210, and yielded pearls worth $164,261. The shells are used in the manufacture of pearl buttons. Perhaps nothing in the work of the bureau is more spectacular than its development of a new fish industry— the catching and marketing of tile fish. This edible and nutritive fish was practically unknown in the market prior to October of 1915. Beginning with November, 1915, and up to August, 1916, 6,938,000 pounds of tile fish have been taken and marketed for $255,000. So rapidly did the fish impress consumers with its value that the July, 1916, catch was over 1400 per cent greater than that of the previous November. Fish cultural work was conducted in thirty-two States and the territory of Alaska. Distributions oc- THE FISH WE EAT curred in every State and Territory of the Union. The greater part of the output is planted in public waters, either on the initiative of the Fish Commission or on the recommendation of State authority, although fishes adapted for ponds, small lakes and minor interioj* waters are usually consigned on individual application. Fish cultural operations were conducted during the year at fifty permanent hatcheries and seventysix sub-hatcheries, auxiliaries and egg-collecting stations. These various stations and sub-stations are located along the Atlantic rivers for salmons, trout, white perch and yellow perch ; the Pacific rivers for .salmons and steelhead trout ; on the Great Lakes for whitefish, Cisco, lake trout and pike perch; on various interior waters for bass, sunfish, carpies, trout, and on the Atlantic Coast for cod, haddock, pollock, flounder and lobster. lakes and bayous formed by the overflow of the Mississippi and Illinois Rivers and their tributaries. During 1915 operations of this character yielded 8,357,000 fish, which is approximately 90 per cent of the food fishes which would otherwise have perished through drought or "air drowning" when the overflow dried up, or from cold later in the year if not rescued. The Bureau of Fisheries has six railroad cars especially arranged for the transportation of live fish During the year ending June 30, 1915, the distribution of fish, eggs, etc., by the bureau amounted to 536,260,143 eggs, 3,694,281,699 fry and 58,215,692 fingerlings, yearlings and adults. These went to Fish Commissions in twenty-eight different States, to waters needing stock, from the controllers of which requests had been made to the bureau, and to private persons asking for fish for streams, lakes or ponds. While in special instances some fish or eggs are sent by special messenger, by far the greater part was sent out by means of the bureau's special fish and egg transportation cars. The Bureau of Fisheries has been investigating and encouraging wherever possible the establishment of the home fish ponds and in every way possible places its accumulated experience at the disposal of persons interested in the establishment DEPOSITING FISH IN A STREAM of fish ponds for the purpose of supplying fish for the table. It is impossible, adequately, to convey an idea of the scope of operations of the Bureau of Fisheries in the short space available here Those interested should communicate with the Commissioner of Fisheries, Bureau of Fisheries, Department of Commerce, Washington, D. O, FOREST RANGEE AT HIS FIRE LOOKOUT STATION IN THE TOP OF A YELLOW PINE. MT. SHASTA IN THE BACKGROUND. A TELEPHONE AT THE FOOT OF THE TREE CONNECTS WITH THE SUPERVISOR'S OFFICE States amounts to nearly 2,JXX),000,000,000 board feet, of which three fourths (about 2,200,000,000,000 board feet) is privately owned and 21 per cent (600,000,000,(K)0) is conserved in national forests. The remaining 4 per cent is otherwise publicly owned by States or municipalities. struction of 12,000,000,000 board the original stand of timber in the I'nited States is calculated to have been 5,200,000,000,000 feet, covering 800,000,000 acres. Nearly half the country's timber is in the Pacific Northwest, a fourth of it is in the Southern Pine region, and the balance in the Lake region and scattered in the Eastern States. Most of the national forests are in the mountains of the West, following in general the Rocky Mous- feet, and waste as much more. Many saws waste as much as they cut, and stumps, slashing and slabs account for a tremendous loss. It is probable, although not computable accurately, that fires and waste use more lumber than is cut yearly. a statement borne out by the fad (hat tains and Pacific Coast ranges from Washington, Idaho and Montana to southern California, Arizona and New Mexico. A few are in Arkansas. Florida, Nebraska. Michigan, Minnesota, Alaska and Porto Rico. States which have set aside forest reserves of their own are California, Connecticut, Indiana, Maryland, Massachusetts, Michigan, Minnesota, New Hampshire, New Jersey, New York, Pennsylvania, South Dakota, Vermont and Wisconsin. SHIFT IN LUMBER PRODUCTION A careful comparison of computed production for 1915 as against reported production for 1914 reveals changes which lumber cutting is ANNUAL CUT Reliable but not absolutely accurate figures of lumber production are furnished by the Forest Service of the United States government. Based on the reports from 16,428 lumber mills, the 1915 cut is estimated to have been 37,013,294,000 board feet, with a possible maximum of 38,000,000,000 board feet. A "board foot" is 12 by 12 by 1 inch. Forty per cent of the cut was Southern yellow pine, three times the amount of Douglas fir, second in quantity cut. But three other itom mills excluded producing in the location of principal supplies. During the year Washington rose from second place to first in lumber production. Louisiana dropped from first to second [ilai-e. Oregon fell from fifth place to seventh. Florida climbed from fifteenth place to twelfth and Minnesota dropped from eleventh place to fourteenth. LOCALITIES OF VARIOUS SPECIES The principal varieties of lumber and the States in which they grow are listed on page 80, the order of the names of States being according to their rank in growing the particular variety of lumber under which they are classified. FORESTS AND FOKKSTUY total number of mills and their capacity, a comparatively accurate figure of total cut can be obtained. But it is not possible accurately to estimate what proportion of the output of unreporting mills may be in lath and shingles. Hence the following figures are confined strictly to reports and are not estimates. As the lath cut increased slightly and the shingle cut decreased decidedly since 1912, the last previous year for which lath and shingle figures are available, they are given for comparison. In 1915 mills reporting showed a lath cut of 2.794,301,000 as against 2.719,163,000 in 1912. In 1915 mills reporting showed a shingle cut of 8,483,579,000 against 12,037,685,000 in 1912. in 1915, with a cut of 6,313,335,000, more than fifteen times as many as any other State, but dropping by a billion and a half under its figures for 1912. BOX MANUFACTURE The largest users of lumber in the United States, excluding builders and millwrights utilizing lumber for products used in construction work, are the box manufacturers. Statistics for 1912 are the most recent ones available. Ac-cording to these, 4,547,973,180 board feet are used annually in the production of boxes, and machines, growers of fruit, berries and vegetables. Crates are used in large quantities by shippers of furniture, hardware, machinery and stone ; also for fruit. mand on the lumber market for crossties and poles. No more recent statistics than those of 1910 are available as to crossties, but in that year nearly 149,000,000 ties were used. Because a tie must be selected for durability, spike-holding power, resistance to mechanical wear and Arkansas, Mississippi, Louisiana crates and other containers. Sixtynine per cent of this amount is soft wood and 31 hardwood. The total amount in 1912 was 1% per cent of the total cut. Leading box consumers are manufacturers of oil, packing-house products, canned goods, groceries and tobacco, clothing and dry goods, the manufacturers of hardware, tinware reasonableness of price, there are but few woods which are chosen by railroads. The principal ones and their popularity by both steam and electric roads are shown in the table on page 82. Railroads, trolley lines, telephone and telegraph companies consume large quantities of lumber yearly in KINDS OF WOODS USED FOR RAILROAD CROSSTIES purchase and use of poles. In 1911, the most recent year for which pole statistics have been gathered, 3,418,020 poles were bought by companies needing them for immediate use. Of this quantity cedar poles were the most popular accounting for over two million, with chestnut, oak, pine and cypress following in the order named. Poles under twenty feet and telephone lines) ; poles between twenty and thirty feet, the most popular size, accounted for 1,861,816 of the total ; between thirty and forty feet, 862,219: between forty ami lifty feet, 217,000, and over fifty feet, 72,257. and the consequent higher prices have led many large users of wood exposed to weather and decay, notably railroads and telegraph and telephone companies, to experiment seriously with processes which servers' Association, gathered in co<>I>eration with the Forest Service, in 1915, 102 wood preserving plants treated 141,858.963 cubic feet of material. The 1914 statistics on wood preservation were based on reports from ninety-four plants and showed a total of 159,582,639 cubic feet treated. Although the figures -for 1915 are based on the output of eight more plants than are those for 1!H4. the amount of wood treated in 1915 was less by 17,723,676 cubic feet, or 10 per cent. A notable increase, amounting to 1.'.isi;.i>i; cubic feet, was recorded in the amount of construction timber treated during the year. The num- ber of crossties subjected to treatment in 1915 was 37,085,585, a reduction from 1914 figures of 6,761,402, while the quantity of paving material was increased by over 300,000 square yards, or 11 per cent. Less than half as many cross-arms were treated in 1915 as in the previous year, and the quantity of piling and miscellaneous timbers treated fell below that reported in 1914 by 1,766,618 and 200,825 cubic feet, respectively, a decrease of 21 per cent and 14 per cent. For the treatment of the 141,858,963 cubic feet of material reported in 1915 33,269,604 pounds of zinc chloride and 80,859,442 gallons of creosote were required. In addition 3.205,563 gallons of paving oil and 1,693,544 gallons of miscellaneous liquid preservatives were consumed. In 1914 paving oil was reported separately for the first time and amounted to 9.429.444 gallons. In 1915 the treating plants reported only 3,205,563 gallons of this heavier tional forests 155 separate areas in the United States, aggregating 184,505,602 acres of land, which includes, preservation of the forests. Wood is cut and sold, mines are worked, water power is developed, sheep and cattle are grazed on these lands as on any others, the difference being that in the national forests all activities are under permits and the forests therefore under protection. Contrary to the general impression, this acreage is not a "reserve" — indeed, the name "forest reserve" gave way to "national forest" to correct that impression. The national forests are protected from fire, from over-cutting, from exploitation indeed, but they are made to serve as large a population as possible by permitting their use in every possible way consistent with the The most recent reiK>rt of the forester shows that the regular appropriation for 1914 for the Forest Service of $5,662,094.13 was not sufficient, and an emergency appropriation had to be made largely on account of a very dry year and the increased necessity for fire protection and lire fighting. The national forests, however, returned to the United States Treasury during the fiscal year the sum of '$2,481,469.35. foregone to sell certain lumber at cost; certain free grazing privileges were worth in excess of $120,000, and other privileges are believed to have a market value of $100,000 a year. During the year 1,093,589,000 board feet of timber was sold. Forty thousand and fifteen free-use timbercut permits were issued and 30,610 permits given for stock grazing. One million six hundred and twenty- A much larger showing could be made were it not for the generous policy of the Government which permits certain privileges free of charge. During the year over $200,0(X) worth of timber was given away free to settlers ; $33,000 of profit was seven thousand three hundred and twenty-one cattle, 96,933 horses, 2,792 hogs, 7,232,276 sheep and 51,409 goats were fed in national forests during the year. Predatory animals, including bears, coyotes, mountain lions, lynxes, wildcats, wolves and wolf pups were destroyed to the number of 3,843, the number indicating only the kill by forest Fires in national forests are guarded against with every possible care, but during the year 6,605 fires occurred. Of these, 3,253 burned less than a quarter of an acre before being extinguished, 1,807 burned less than ten acres, 988 burned less than $100 worth though more than ten acres in extent, 458 fires did damage from $100 to $1,000 and 99 did damage in excess of ten acres and $1,000. A strict census of fire causes shows 16.8 per cent caused by railroads, 30.77 per cent by lightning, 7.12 per cent by incendiarism, 9.02 per cent by badly controlled brushburning, 17.05 per cent by careless campers, 1.35 per cent by stationary steam engines — sawmills, donkey engines, etc. — and the balance of 17.89 per cent miscellaneous and unknown causes. The fires burned in 1914 225,979 timber acres. The open area affected was 153,686 acres, accounting for a loss of timber burned or damaged of 339,430,000 board feet. The loss of money is estimated to be $307,303 for the destroyed timber ; reproduction destroyed, $192,408, and forage loss, $2,803. The service expended in fire fighting, outside of salaries of regular officers, $685,790. NOTE. — It is impossible to give here minute details of all the activities of the Forest Service. Seekers for more detailed information can readily obtain it by writing to the Forest Service, U. S. Department of Agriculture, Washington, D. C. IT is not generally understood that the Reclamation Service of the United States is primarily a •home making" service, nor that it does not compete with private enterprise. Such, nevertheless, are the facts. Early irrigation in this country was entirely a matter, of cooperative effort or the result of investment by private or corporate capital, and early laws to encourage irrigation of arid lands all contemplated construction financed by other than governmental money. The increasing difficulty of carrying out large projects led to the passage of the reclamation act, which enlists national funds for the development of projects not feasible by private or State enterprise. The projects undertaken involved expensive storage works, high diversion dams, difficult tunnels, or long, expensive canal work upon side hills, where large investment was necessary before any water was brought to the land. Many projects discussed in the early days of reclamation work were rejected by the Reclamation Service because deemed within the reach of private investment. Some of those same projects were later taken up by the Government after years of unsuccessful effort to enlist private capital in their construction. Practically all of the projects undertaken by the Reclamation Service had been abandoned after unsuccessful attempts to finance them as private projects, or else were new projects too difficult to attract the attention of promoters. Remarkable progress, since its beginning in 1902, has been made by the service, and at the present time about 1,500,000 acres are under ditches and crops are being produced yearly on more than a million acres. The .average gross return per acre from these lauds annually is about $25. More than 30,000 families have been established in homes of their own. Cities, towns and villages have sprung up in these agricultural communities. Railroads have extended their branches, and a vast region which a few years ago was uninhabited and a desert has been transformed into a prosperous farming country. during a recent year. 82 miles of railroad, 2.554 miles of telephone lines, 42!) miles of power transmission lines, and 1,068 buildings, such as power houses, pumping stations, offices, residences, barns and storehouses. The excavations of rock and earth in all the work amount to 130,149,368 cubic yards. The projects now under way or completed embrace approximately 3,000,000 acres of irrigable land, divided into 60,000 farms of from 10 to 160 acres each. During the year 1915 water was available from Government ditches for 1,450,407 A summation of the work to the beginning of the present fiscal year shows that the service has dug 9,592 miles of canals and ditches, and excavated 89 tunnels with an aggregate length of more than 25 miles. Masonry, earth, crib and rock-filled dams have been erected with a total volume of 12,200,000 cubic yards, including the two highest dams in the world. The available reservoir capacity resulting is approximately 6.500,000 acre feet, or sufficient water to cover the States of New Jersey and Delaware to a depth of 12 inches. The service has built 4,622 bridges with a total length of 19 miles. Its culverts number 5,714 and are 36 miles in length. There are now in operation 298 miles of pipe line and 85 miles of flumes. The service has built 784 miles of wagon road, much of it in what was before inaccessible waountain regions ; WORKMAN neering problems involved are those of settlement and successful utilization of the irrigation system and water supply by the farmers. Without successful agricultural development a project may be a failure, regardless of the perfection of the engineering work. The sufficiency of the water supply and successful operation of the irrigation system are only incidental to the ultimate object sought by the Government as well as the irrigator and the success of the undertaking is inseparably connected with that of the water user. Exclusive of projects constructed for the Indian Service. sion of desert tracts into self-supporting agricultural communities. This object is not obtained by the construction of irrigation works alone, however elaborate or efficient these may be in design and operation. More difficult than the engi- To show progress in reclamation work it is necessary to show the results obtained by the farmer as well as those of the engineer. Reclamation is measured not in engineering units, but in homes and agricultural values. For lands under the Huntley project there is an additional charge of $4 00 i er acre for the land, of which $1.00 is payable at the time of entry and the remainder in four equal annual instalments. For information concerning those projects and method of obtaining land under them, or any additional statistics not covered in t his brief chapter write to Statistician, Reclamation Service, Interior Department, Washington D C The table on page 89, therefore, is even more illuminative of the success of the work than any engineering statistics alone can possibly be. By no means all available lands embraced in the various projects is taken up, and every effort is being made by the service to see that they are properly and successfully settled. The table above shows the number of farms available for POWER DEVELOPMENT In connection with the construction of irrigation work, particularly of dams on the larger rivers, it has been necessary to develop power. Power plants are operated principally for pumping water for irrigation; incidentally for other purposes, the excess power heing sold for domestic or industrial uses, such as lighting, heating, cooking and operation of machinery. Pumping forms the principal use of the electric power development, and there were installed 10,432 horse-power in i»er- 1 1 ours is 66,199,624, and the cost per kilowatt hour ranges from 3.82 cents at the North Dakota Williston plant down to 0.111 cent at the Minidoka plant. The developed power not needed for irrigation pumping is sold to customers for construction, for camp lights and for drainage work and results in a gross income of $249,174 from power sales, which is almost 10 per cent on cost of installation. But all these figures fade into insignificance when consideration is had of the accompanying table show- nianent pumping plants used in 1914, in addition to numerous small drainage installations semi-portable and intermittently used. The cost of raising 1 acre-foot 1 foot ranges from 0..368 cent to 2.10 cents. The capacity of all the power plants operated by the service was, in 1914, 27,1:54 kilowatts from 37 units. The water head ranges from 226 feet at the Roosevelt plant to 21 feet at the Arizona Falls plant. The total cost of all the plants was $2,542,159. The output in kilowatt cash on hand. During the year this amount was augmented by receipts from various sources to a grand total of $16,446.794.66. Of the twenty millions authorized by the act of June 25, 1910, eight and one half millions were transferred to the reclamation fund. By the processes of the General Land Office and the Treasury DP partment the receipts from sales of public lands are held in the Treasury from six to nine months before they are placed to the credit of the reclamation fund. Estimated receipts from the sale of public lands RECLAMATION SERVICE in the hands of the Treasury Department on June 30, 1915, which had not been credited to the reclamation fund amounted to approximately The reclamation fund, which comprises the moneys received from the sale of public lands, has now reached the total of $85,914,493.36, and from the sale of town-sites, $280,723.94. Transfer vouchers, adjusting accounts between the projects for the transfer of the value of services and equipment, amounted to $615,657.58 during the fiscal year 1915. Since the beginning of the service the value of the transfers of supplies, materials, equipment and services between projects has amounted to $5,006,759.37. This system of transfers between projects enables the service to utilize equipment, materials, supplies, etc., to their fullest extent where needed and to charge the cost where the benefit accrues. ESTIMATED COST OF CONTEMPLATED It is estimated that during 1916 the sum of $11,113,902.67 will be expended. The table on page 92 gives the tentative distribution of this amount to the various functional features of all projects, including the Blackfeet, Flathead and Fort Peck Indian projects. can name the national monuments, or explain the difference between a national park and a national monument? Very few I And such almost wholesale ignorance is one of many reasons why a Bureau of National Parks, as a part of the Interior Department, has for many years been a vital necessity and why every loyal American, whether he ever sees a national park or not, should rejoice that Congress has finally passed the National Parks Service Bill. This bill, far reaching in import, reads in part as follows : "Be it enacted by the Senate and House of Representatives of the United States of America in Congress assembled, That there is hereby created in the Department of the Interior a service to be called the National Park Service, which shall be under the charge of a director, who shall be appointed by "the Secretary. . . . The service thus established shall promote and regulate the use of the Federal areas known as national parks, monuments and reservations, which purpose is to conserve the scenery and the natural and historic objects and the wild life therein and to provide for the enjoyment of the same in such manner and by such means as will leave them unimpaired for the enjoyment of future generations." As yet the service is but a name, for the Sixty-fourth Congress lias not yet provided an appropriation to form the service. But everything is ready and as soon as the money is available our numerous parks and monuments will have the service of their own they have so long needed. There are sixteen national parks at present in existence, the first of 46 hot springs possessing curative properties. Many hotels and boarding houses. 20 bath houses under public California height. 3 groves of big trees. High Sierra. Large areas of snowy peaks. Waterwheel falls. Good trout fish- NATIONAL PARKS which was Hot Springs, In Arkansas, created in 1832; the most recent, Hawaii National Park and Lassen National Park, being creations of the Sixty-fourth Congress, the bills for the two parks being approved August 1 and 9, 1916, respectively. The first purposes of the parks are the preservation of scenic beauty and natural wonders for educational and recreation purposes. They make wonders of certain regions free to all the country; indeed, to all the world. Though Hot Springs wras the first of all the parks, it was the creation of the Yellowstone National Park in Wyoming, Montana and Idaho, by the act of March 1, 1872, which really marked the beginning of a policy on the part of Congress of setting aside tracts of land as recreation grounds for all the people. More and more are we coming to know what wo possess in those parku and the war abroad taught us afresh that Europe has nothing in scenery more worth seeing than what we have at home. In the Yellowstone National Park there were 20,250 visitors in 1914, and in 1915 two and one-half times as many, 51,895. Yosemite National Park in California had 33,452 visitors during the 1915 season, whereas in 1914 only 15,145 persons visited the park. Again, in Mount Rainier National Park, Washington, there has been an increase in the number of visitors as against 15,038 in 1914. But it has been discovered that national parks have a distinct commercial value, as well as an educational and recreative one. The parks produce an ever increasing revenue from tourist traffic, one of the most satisfactory means of revenue a nation can have. The tourist leaves large sums of money but takes away nothing which makes the nation proved health, with a recollection of enjoyment of unequaled wonders of mountain, forest, stream and sky, of vitalizing ozone and stimulating companionship with nature; but of the natural wealth he takes nothing. The commercial potentialities of tourist traffic are startling. It is estimated that in time of peace Switzerland's annual revenue from tourists is $150,000,000, that of France $600,000,000; little Italy's, $100,000,000. It is claimed that Americans have spent $500,000,000 a year in travel abroad. The pine woods of Maine are estimated to bring a revenue of $40,000,000 each year on account of the visitors they attract, and the orange blossoms of Florida are worth more to her than the products of her soil. Every dollar, therefore, which is spent by the nation on national parks may De considered an investment which is likely to bring in a very satisfactory return upon the money invested. 4,218.51 That this is not a mere speculalion is shown in the table above, totaling the economic value of tourist travel to Yellowstone. Yosemite, Glacier and Mount Rainier national parks during the past four years, together with the revenues. The national parks cover an area of more than 4,700,000 acres. If all were put together it would mean an area of more than 7,300 square miles, practically as large as New Jersey. The Yellowstone National Park, containing more than 3.300 square miles, is as big as many of the independent European principalities that warred with each other for centuries before the genius of Bismarck united them into a great empire. Such a group of scenic areas, developed and handled after the fashion of Switzerland, would constitute a national economic asset of incalculable value. It is not for their educational, recreative, or economic value alone, however, that the national parks must be regarded. The conservation of wild life is a feature not to be despised. Free as most of the parks are from public lumbering and private grazing enterprises, and protected from hunting of any kind, they have the conditions essential for the protection and propagation of wild animal life. Eventually they will become great public nature schools to which teachers and students of animal life will repair yearly for investigation and study. became a national park in 1872 points the way. Deer, elk, moose, bison and antelope here abound in greater numbers, no doubt, than before the days of the white man ; and many of them have become almost as fearless of man as. animals in captivity. From here many State, county and city parks have been supplied, under proper restrictions, with surplus animals for propagation purposes. When interfering private holdings are extinguished in other national parks, and United Stairs laws made to supersede State laws (a condition the newly authorized Park Service will strive to bring about), these, too, will become centers of animal preservation as effective as the Yellowstone. By an act approved June 8, 1906, entitled "An act for the preservation of American antiquities," the President of the United States is authorized, "in his discretion, to declare by public proclamation historic landmarks, historic and prehistoric structures, and other objects of historic or scientific interest, that are situated upon the lands owned or controlled by the Government of the There are now thirty such national monuments, two which' did exist having been eliminated with the creation of Lassen National Park. public roads in the United States. Of these, 10.9 per cent (a total of 247,490 miles) are surfaced roads— roads other and pre- in the dirt. Rhode Island leads all the Union in £ood roads, with a percentage of r.s.s per cent. Massachusetts comes resenting 250 miles of surfaced roads out of a total of 80,338. Other backward States are Nevada, 0.5 per cent, Montana 0.4 per cent, and Kansas 1 per cent. COSTLY WAY CHEAP WAY Ohio has the greatest good road mileage, with 28,312, Nevada the least, with 65 miles. Texas has the greatest total mileage with 128,971, Rhode Island the least with 2,121. During the past twenty years State governments have been active in a constantly increasing measure in behalf of road improvement. To January 1, 1915, expenditures aggregating $211,859,163 had been made from the appropriations by the legislatures of 39 States. With these funds improved roads to the extent of 35,477 miles have been constructed during this period of twenty years at an average expenditure of $5,970 per mile. Yet we have not good roads — and we are paying the price. We pay in money, in lives, in ignorance, in labor, in taxes, and in high cost of living. Considering only a few phases of the subject, the investigator is struck with the universal effect of good roads. Census, compared with the road statistics, show clearly the relationship between illiteracy and bad roads. Many factors contribute to produce illiteracy, but it is significant that where one is found, there is usually the other. In Arkansas, Missouri, Mississippi and North Carolina, where less than 2 per cent of the roads are improved, there were 374,788 native born white illiterates in 1900, out of a total population of 7,800,000, whereas in Massachusetts, Connecticut, New Jersey and Rhode Island, where 30 per cent of the roads are improved, there were only 20,500 native born total population of 6,025,000. The cost of poor roads is a terrific item in high cost of living. It costs more to ship a ton of 'cotton from farm to railroad than from New York to London, as is plainly table above. Of the 3,114,300 autos in the world this country possesses 2,400,000— more than one for every mile of road. In 1916, 1,200,000 more will be manufactured. If the cars average $500 each in value, and bad roads cost 10 per cent depreciation, these scrapped cars, due to poor roads, cost the United States $120,000,000 per year, more than half what has been spent on good roads in twenty years ! Now the Federal Government has taken hold of the problem and the sum of $85,000,000 of Federal funds was made available for constructing rural roads by the Federal Aid Road Bill, which became a law July 11, 1916. For the construction of rural post roads under co-operative arrangements with the highway departments of the various States, $75,000,000 is to be spent, the remaining $10,000,000 being for roads and trails within National forests. The Federal Government's share in be 50 per cent of the cost. Five million dollars is available for expenditure before June 30, 1917 Appropriations increase at the rate of five millions a year until 1921, when twenty-five millions is provided, making a total of seventy-five millions. One million dollars a year for ten years is for the development of roads and trails within National forests. The class of roads to be built and the method of construction are to be mutually agreed upon by the Secretary of Agriculture and the State highway departments. The Act provides that the Secretary of Agriculture shall apportion the appropriation in the following manner: One-third in the ratio the mileage of rural delivery routes and star routes in each State bears to the total mileage of rural delivery routes and star routes in all the States. States securing Federal aid must make needed repairs and maintain a reasonably smooth surface, but are not obliged to make extraordinary repairs or undertake reconstruction. The Secretary of Agriculture, July 21, 1916, certified to the Secretary of the Treasury and the governors and State highway departments of the several States the apportionment of the first $5,000,000. In accordance with the Act, 3 per cent, or $150,000, needed for administration was deducted. The narrow strip of land ten miles wide, crossing the Isthmus of Panama, called the Canal Zone. On August 15, 1914, the Panama Canal was opened to commerce. Between these two dates lie all the wonder of the construction of the greatest engineering feat of all time. But that story has been told and retold. What concerns us now is what the canal accomplishes, how it does its work, what it costs — what it is worth. The distance by water around South America is 10,500 nautical miles from Colon (Atlantic) to Balboa (Pacific). By canal the distance between the same two points is 44 miles. canal. So far in the use of the canal, over 40 per cent of the vessels which have passed through it have been engaged in the coastwise trade of the United States — each of them saving about 7,800 miles on each trip. If their average speed be taken at ten knots, they have averaged a saving of over a month at sea on each voyage from coast to coast. Where formerly the round trip of a ten-knot vessel required about fifty-five days' actual steaming, the time at sea for the same The transit of the canal requires about 10 hours, of which approximately 3 hours are spent in the locks. In the sea-level channels and Gaillard (formerly "Culebra") Cut, speed is limited to 6 knots ; through Gatun Lake they may make 10, 12, any charted channel. The canal channel is accurately charted, fully equipped with aids to navigation, and governed hy rules which the pilot, one of whom must be on any vessel going through, enforces. LOCKING THROUGH As a vessel approaches the locks, the operator at the control house indicates by an electrically operated .signal if the vessel shall enter the locks, on which side, or if it shall keep back, or moor alongside the approach wall. If everything is ready for the transit of the locks, the vessel approaches the center approach wall, a pier extending a thousand feet, and connections are made with the electric towing locomotive. The vessel then moves forward slowly until it is in the entrance chamber, when lines are thrown out on the other side and connections are made with towing locomotives on the side wall, six for the larger vessels, three on each wall of the lock chamber. Two keep forward of the vessel, holding her head to the center of the chamber ; two aft, holding the vessel in check ; and two slightly forward of amidships, which do most of the towing. The locomotives are secured against slip- ping by cogs in a rack. They are equipped with a towing windlass, which allows the prompt paying out and taking in of hawser. The water within the lock chamber proper, beyond the entrance chamber, is brought to the level of that in the approach, the gates toward the vessel are opened, a fender chain is lowered, and the locomotives maneuver the vessel into the chamber. The gates are closed, the water raised or lowered to the level of the next chamber, the gates at the other end are opened, and the vessel moved forward. Three such MAY 20, 1913 Ocean-going vessels to the number of 787 passed through. the canal from July 1, 1915, to June 30, 1916. Their aggregate net tonnage was 2.470,701. Cargo carried through the canal on thesi> ships amounted to .'U4(MM«. tons, and the ships paid in tolls $2,389,830.42. The canal was closed in September, 1915, and remained closed, except for the transit of small vessels which had waited at the entrances for passage, until the mid- half the year. The number of ships which passed through the canal during the preceding fiscal year was 1,088, aggregate net tonnage 3,843,035, cargo carried through 4,969,792 tons. Their tolls amounted to $4,343,383.69, after all refunds had been made. Canal tolls are as follows: Merchant vessels, passengers or cargo, per net ton (each 100 cubic feet) of actual earning capacity, $1.20. or cargo, per ton 75 cents. Naval vessels, other than transports, colliers, hospital ships, and supply ships, per displacement ton, 50 cents. On June 30, 1916, the total receipts of tolls from vessels passing through the canal were $2.399,830.42. The total amount expended on account of the operation and maintenance of the canal was $6,999,750.15. leaving a deficit to the amount of $4,599,919.73. For every dollar the Government spent for operation and maintenance it received back in tolls 34.28 cents. It spent practically three times as much to maintain and operate the canal as it received in tolls. During the preceding fiscal year the tolls had exceeded the expenses by $276,656.38, which represented a profit of 0.67 per cent on the expenditure for operation and maintenance alone, not counting anything for interest on the money invested or for depreciation of plant. Tolls on vessels in the United States coastwise trade amounted to 18.36 per cent of all tolls collected in 1916. During the preceding fiscal year, coastwise traffic yielded over 36 per cent of the total, or practically double the proportion which existed during the fiscal year 1916. To the uninitiated, to whom these charges may seem heavy, the following example is given to show their justice and the saving effected by the canal. about 26.8 days at sea on each voyage from coast to coast. The "Arizonan" is a relatively large vessel, 470 feet long by 57.2 feet in the beam, and has carried as much as 11,780 tons of cargo through the canal on one of her voyages. The canal tolls levied on each passage are $7,891.20. The cost of operating the "Arizonan" at sea may be taken at $450 a day. For 26 days this means $11,700, from which the subtraction of the tolls leaves a net voyage. Partly because of the many slides and the cost of their removal, partly because of the fact that they closed the canal for six months in a year and partly because of the war, the tolls do not by any means pay expenses. CHANGE IN TOLLS CHARGES During the first months tolls were levied on the basis of the net tonnage of ships determined by specially formulated rules for measurement for the Panama Canal, in which the net tonnage was the space available for carrying cargo, reckoned in tons of 100 cubic feet. Following an interpretation of the Panama Canal Act by the Attorney General, the amount of tolls collectable has been governed also by the net tonnage as determined by the rules for registry in the United States, it having been decided that the tolls should not exceed $1.25 per net ton on this basis. The result of this system has been a loss in revenue. During the fiscal year ending June 30, 1916, the tolls collected amounted to $2,395,928.77. If the original Panama Canal rules had been adhered to, collections would have amounted to $2,786,642.82, a difference of $390,714.05, 14.05 per cent of the hypothetical CHARACTER OF FREIGHT. Twenty principal commodities together made up 67 per cent of all cargo carried through the canal, being 2,009,897 tons out of a grand total of 3,140,046 tons. The miscellaneous articles other than the twelve principal commodities aggregated 1,130,149 tons. Nitrates amounted to 894,139 tons ; refined petroleum to 271,041 ; coal, 243,216; sugar, 128,544; lumber, 96,685; manufactured goods of iron and steel, 87,375; crude oil, 69,812; railroad material, 57,829; iron ore, 52,250; canned goods, 41,300; barley, 38,006; and copper, 36,700 tons. CANAL FORCE Many people have an idea that because the canal is finished and open for business therefore the Isthmus is depopulated. How far wrong this is may be seen by the following statement of the working force actually engaged during the last week of July, 1916: . 24,121 of whom 3,747 were men, 1,454 women, and 1,571 children; and 10,925 West Indians, of whom 5,880 were men, 2,188 women, and 2,857 children. Balboa was put in active commercial service the last of August, 1916. The first use of the dock was on June 27, with the docking of the dredge "CorozaV and since that time other canal vessels have been docked. The first privately owned vessel to make use of it was the 81-ton auxiliary schooner "Chiriqui," registered in Panama, which entered the dock on Tuesday, August' 22. The first commercial use of the new coaling plant at the Atlantic terminus of the canal was made in the morning of Wednesday, August 30, when the steamship "Otaki" was taken alongside the reloader wharf to receive 550 tons of coal. So mxich has been said of the closing of, or interference of the operation of, the canal by slides, that most people have a confused idea that the mountains on each side of the canal are gradually sliding into it, and some have even come to believe that the canal will one day be known as a gigantic en- gineering failure. Space forbids going into the subject. But for the comfort of those who are anxious lest we have spent our money and time for nothing, the following quotation from Major General George \V. Goethals' paper on "Slides at Panama, "published Jan. 5, 1916, may well be printed here: "It is certain the slides are due to the failure of underlying strata, because these were unable to bear the weight that the banks brought upon them. "Under the circumstances it is difficult to understand the impression .that has gained credence in some quarters that a sea-level canal would have avoided the difficulties encountered, since the cutting would have been through the same material, but at least SO feet deeper. "It is also certain that nothing can stop the movements until the angle of repose is reached for the materials under the conditions that exist, and that this can be reached only by removing the excess amount of material. If experience counts tor aught, then that gained in the handling of the slides and the breaks that have occurred along the line of the canal leaves no doubt that the means adopted and now in use will effect a cure; furthermore, that when cured no further troubles need be anticipated from slides in this locality." edge of those resources. It is with these that the Geological Survey is concerned, with their investigation, their development and their proper exploitation. 35,000 square miles. The land classification work of the Geological Survey last year resulted in the classification of about 36,000 square miles in the public land States. In the collection of statistics of mineral Spending $1,620,520 in the last fiscal year for which a report is available (to June 30, 1915) the Geological Survey's work can hardly be summed up in a sentence. During the year geological investigations were made in 47 States and Alaska; topographic surveys were made in 30 States, Alaska and Hawaii, and stream measurements were made in 41 States and Hawaii. Tho total area covered by geologists in reconnaissance and detailed surveys was more than 76,000 square miles production the Geological Survey cooperated with the State geologists of 16 States and carried on correspondence with 90,000 producers, as well as answering over 50,000 letters of inquiry. The bureau divides its activities into the Geologic, Topographic, Water Resources, Land Classification, Publication and Administrative branches. THE THREE GREAT GOVERNMENT SURVEYS branch were the classification of the public lands and the examination of the geological structure, mineral resources and products of the national domain. These duties were at first construed to apply only to the public land States. Later, however, in order that all parts of the country might share alike in the benefits of its work, the survey was specifically authorized "to continue the preparation of a geological map. of the United States," the scope of its the earth's crust and its mineral constituents. The survey is a source of geologic information regarding not only the geology of the United States and its possessions, but also that of Mexico, Central America and even South America. By correspondence it is asked for .data regarding the geology and mineral deposits of all parts of the world. The geologic branch has the double task of geologic surveying, including the investigation, description SURVEYS PRIOR TO JULY 1, 1915 operations being thus made nationwide. Since that time (1882) the investigations necessary to the fulfillment of the survey's obligations to the public have become as varied as the aspects of geology itself. The geologic branch is the effective agency of the survey in investigations in all parts of the United States and Alaska and also the great geologic information bureau to which the American public, from Key West to Point Barrow and from San Diego to Eastport, applies for knowledge of every sort concerning and mapping of the geology and mineral deposits of all parts of the country; the classification of the public lands and the publication of the results of its work, and furnishing to the public miscellaneous geologic information derived from all sources. But it is not to the general public only that its services are rendered direct. Probably no one bureau of the Government co-operates with so many others in their work as does this survey. Bureau of Mines in the metallographic study of ores, in the investigation of the invasion of California oil wells by salt water, in studies of the application of geology to engineering problems of mining and construction and in the examination of placers and placer mining in the United States. The survey is engaged with the Bureau of Standards, the Bureau of Mines and the Office Justice in connection with suits regarding public lands ; to the Navy Department in regard to oil and water supplies; to the Office of Indian Affairs in the classification of Indian lands ; to the War Department with reference to water supplies in its reservations, and to the General Land Office in the classification of withdrawn coal, oil and phosphate lands. COAST AND GEODETIC SURVEYS of Public Roads in a systematic study of building stones. It cooperated informally with the Smithsonian Institution, Bureau of Fisheries, Forest Service, Navy Department, War Department and Lighthouse Service, as well as with institutions of learning, including the Geophysical Laboratory and Marine Biological Station of the Carnegie Institution. Services are rendered to the Department of Agriculture in the examination of lands in the national forests ; to the Department of Topographic Work The general public is perhaps more familiar with the work of the topographic branch of the survey than with any other, since most people at one time or another have use for accurate maps of the country in which they live or intend to visit. Carried on in co-operation with the States, the work of mapping the whole country has made great progress, 40.2 per cent of the entire area — and that the most important, economically considered — h a v i n g at a nominal price. A key map, showing just what portions of each State are available, should be secured first by application to the survey, from which selections can be made as desired. The maps are in color and accurate with the accuracy of the highest degree of engineering skill. Classification Immensely important though they are, space forbids any extensive report of the work of the water resources branch. Full information in regard to the water work in fortyone States and Hawaii, of which twenty-six have co-operated, as have the Reclamation, Indian and Public to the survey. Similarly the land classification, and the withdrawal and restoration of public lauds with relation to their oil, coal and mineral deposits, is a subject too big for extended notice here and too special for a popular report. More than 36,000 square miles of land were classified in the year just passed. The work of the Geological Survey is largely made available to the public by distribution of printed reports and maps. The publications of a year consisted of 1 annual report, 1 monograph, 5 professional papers, 10 separate chapters from 2 professional papers, 35 bulletins, 30 separate chapters from 5 bulletins, 33 water supply papers, 18 separate chapters from 4 water supply papers, 1 annual report on mineral resources for 1913 (published also in 62 advance chapters, 15 delivered in 191314 and 47 in 1914-15), 5 advance chapters from the annual report on mineral resources for 1914, 3 geologic folios, 2 lists of publications, 1 list of topographic maps and folios, pamphlets entitled "Topographic Instructions of the United States Geological Survey, 1915," and "Service Bulletin, 1914," leaflets entitled "Nature and Uses of Topographic Maps," PRECISE LEVELING "The Production of Copper in 1914" and "The Production of Spelter in 1914," 3 circulars concerning geologic folios, 22 index map circulars, 55 press bulletins and 10 monthly lists of new publications. A complete list of all Geological Survey publications, with their cost price, can be obtained from the SuI>erintendent of Public Documents. Government Printing Office, Washington, D. C., to whom application should be made by those desiring to obtain such publications. Maps, however, are obtainable from the survey direct, as stated above. A bureau of the Department of Commerce, the Coast Survey performs work seldom heard of by the general public, of the most vital importance not only to the scientific world but the public itself. Every coast chart, on which the vessels of the navy and the maritime world in general depend for safety of both life and property, is made by the Coast Survey. Its tions in harbors and along the coasts, are published by the Coast Survey. Most remarkable of books, these enormous summaries of calculations are not the work of human hands and brains but the result of the labor of the most wonderful calculating machine in the world — the tide predicting engine. A huge affair of wheels and shafts, occupying a mahogany and glass case which fills a room of the bureau, this most accurate and intricate of machines does the work of a hundred computers and more accurately than any human being could do it. In addition to the preparation and printing and issuing of coast charts, the survey conducts triangulation work which will in time gridiron the whole United States, determines latitudes, investigates magnetic phenomena, conducts precise leveling, makes special surveys and performs a host of special duties, such as supplying experts for duty on International Boundary Commissions, International Geodetic Association, Board of Life Saving Appliances, Mississippi River Commission, cooperation with Alaskan Engineering Commission, etc. Its hydrographic work for coast charts is of the highest importance and its development of .what is known as the "wire drag" has revolutionized all such work. No matter how closely soundings may be made of a harbor, for instance, it is impossible to be certain that all sunken rocks, wrecks, shoals or other obstructions to navigation have been discovered. But with a submerged wire drag of a known depth, dragged through the water between two widely separate vessels, a positive result is obtained resulting in a security beyond price to the mariner. In its work the Coast Survey sends out numerous parties which work along the coasts, or, if triangulatioa or leveling is being done, in the interior. Many vessels are used for coast work, including the steamers "Bache," "Endeavor" (now sold), "Hydrographer," "Isis," "Explorer," "G e d n e y," "McArthur," "Patterson," "Taku" and "Yukon" and the schooner "Matchless." In the Philippine Islands five vessels aid the work of the survey, reporting to the suboffice at Manila. This work is prosecuted partly with funds of the survey and partly with funds from the Philippine Govern- IN THE PHILIPPINES ment, which also furnishes four of the five vessels engaged. The ships are the "Pathfinder," "Marinduque," "Romblon," "Fathomer" and "Re- It is difficult, if not impossible, to cover in a few words the extensive and varied work of a bureau which requires a closely printed report of 156 pages to show a year's activi* ties. But in spite of the fact that the determination of astronomic latitudes, the determination of gravity intensity, the prosecution of triangulation, the wire-drag hydrographic work which last year discovered and charted hundreds of shoals and obstructions to navigation, the coast pilot work, the tidal determination and publications, the assistance rendered vessels and mariners in distress, the precise leveling, the special surveys and special services rendered by the bureau, the determination of magnetic elements, dip, declination and horizontal intensity made in 31 States, are all highly important, it is after all the coast charting and the printing and distribution of these charts which are the most indispensable features of this highly important scientific bureau. the press. The charts issued during the year were 119,387, an increase of 1,895 over the previous year. Thirty-nine thousand one hundred and twentyfour of these charts were issued to the Hydrographic Office for navy use and 52,853 supplied the merchant marine through sales agents. Coast pilots were issued to the number of 6,291, and tide tables for the Atlantic Coast 2,050, Pacific Coast 10,775, General 2,206. The appropriation for 1915 was $1,039,730. For 1916 it was $1,365,620, most of the increase being for two new and badly needed vessels. The money is expended as follows: Two new vessels 289,000 The urgent need of the Coast and Geodetic Survey is for new quarters. Occupying several old build- Ings, none of them built for the purpose (one was once a hotel, another a private house!) much time, money and efficiency is wasted from lack of proper facilities. Already in the first rank in naval and maritime importance, this Government bureau will, when allowed to expand and work under proper conditions, take its place in popular estimation with other better known but no more important bureaus of the Government which, because of their popular appeal, fare so much better at the hands of Congress. The Hydrographic Office also publishes sailing directions and manuals for the safe navigation of vessels based on the original surveys and reports, or upon similar publications or information received from foreign hydrographic offices. The Hydrographic Office also issues a number of publications. The Weekly Notice for Mariners is a publication for which the demand increases greatly from year to year. During the fiscal year ending 1915, 277,420 whole weekly notices and 241,748 extracts therefrom were pub- The Hydrographic Office of the United States Navy supplements the work of the Coast and Geodetic Survey in chartmaking by providing both for the United States naval vessels, and for all mariners who have use for them, charts of the coasts of all the world. lished. The information given in this journal is in regard to the correction of existing charts, sailing directions necessary and essential to safe navigation, such as changes in lights, buoys, beacons, wrecks and shoals. the immediate safe navigation of vessels, which include the presence of icebergs, field ice, derelicts, wrecks, missing buoys, etc. This information, in addition to being published in the Daily Memorandum, is telephoned or telegraphed to the various radio stations and sent broadcast to all shipping four times a day. The Hydrographic Bulletin, which is issued weekly, totaled for the past year 247,468 copies. It contains the vessels of the navy. It furnishes free of cost to all other Government vessels such charts and publications as are requested, and the same material is sold at the cost of printing and paper to the merchant marine or the public in general. By international agreement the United States receives from all foreign hydrographic offices two copies of all charts issued by them, and supplies to them two copies of all charts issued by it. Of all foreign WIRE DRAG FOR SURVEYING THE SURFACE OF THE BOTTOM many items of interest to seafaring people and is an important member of the publication family of this office. book publications are issued by the Hydrographic Office, which are necessary to the maritime public. They include such volumes as American Practical Navigator, List of Lights, International Code of Signals, Line of Position Tables, Africa Pilot, British Island Pilot, Mediterranean Pilot, etc. The Hydrographic Office supplies all charts and navigational publications, whatever their character, to hydrographic offices the British Admiralty is, of course, the largest and most efficient. The United States has had to depend very largely upon charts issued by the British Admiralty, not only for information but for the actual charts themselves, so that the number pui'chased in the past year was 19,222. Altogether at the end of the fiscal year the United States depended upon the British Admiralty for 1,494 individual charts of various parts of the world. These, however, are rapidly being reproduced by the Hydro- of this reproduction will be both to save the purchase price of such charts from a foreign government and to make the United States independent of any foreign government for the supplying of world charts to its own navy. Navigational charts to the number of- 123,158 and pilot charts to the number of 205,226 were published on a large scale and covering the approaches to the Panama Canal, has been issued. Pilot charts are in great demand, showing, as they do, tracks of just past storms, prevailing wind directions, compass variation and other maritime information, making them extremely valuable CHART OF THE NORTH ATLANTIC OCEAN by the Hydrographic Office during the past year. At the end of the year the Hydrographic Office had on issue the following charts: The pilot charts are published monthly for the North Atlantic, North Pacific and Indian Oceans and quarterly for the South Atlantic and South Pacific Oceans. In addition to these a new pilot chart of Central American waters, printed Sixteen branch Hydrographic Offices are maintained, located as follows: Boston, New York, Philadelphia, Baltimore, Norfolk, Savannah, New Orleans, Galveston, San Francisco, Portland, Ore., Seattle, Duluth, Sault Sainte Marie, Chicago, Cleveland and Buffalo. In addition to these there are 52 agents in the United States, located in 37 cities and towns, and 12 agents in foreign countries for the sale of Hydrographic Office publications. TAKING UP SAMPLES OF BOTTOM WITH HAND REEL tributing bydrographic information. They endeavor to give assistance to officers and men of merchant vessels both as to data pertaining to the seas traveled and personal instructions in navigation. The popularity of the work of assistance rendered by these branch offices is shown by the large number of ship captains, agents, pilots and other seafaring men who visited the several branch offices during the year. In 1915 there was a total of 40,646 visitors and over 26,000 telephone calls, relative to correct chronometer time and other items of nautical information were answered. A large supply of all charts issued by the office is kept on file in the main office in Washington. Sending these out on demand is a very important work of the Hydrographic Office, since to issue a chart not up to date in any and every particular might cost many lives and the loss of much property. Thus no chart is sent out until it has been corrected to date and by hand with all alterations .made necessary by changes in lights, new information in regard to depth, the presence of wrecks or other obstructions to navigation, etc. As an indication of the size of this work it may be mentioned that during the fiscal year there were transferred from old to new copies of charts some 18,000 corrections, and handled by requisition or for plotting and reference about 9,000 charts. Including new issues the total number of copies of charts printed during the year was 328,484. States also occupies the proud position of having the largest, finest and most competent lighthouse establishment in the world. Not yet has it reached the full flower of I>erfection which will obtain when the ideal of the service is realized — lighthouses so numerous and so well placed that it will be impossible for a coastwise vessel to sail out of the radiance of one without coming into view of the next. But great progress has been made toward this end, and the building, both of structures and of traditions, of apparatus and of the service itself, has been so well and carefully done that the service is a permanent asset not only to all our own shipping, but to the shipping of the world. Moreover, to the credit of the country be it said, there are no "light dues" which any foreign or domestic vessel must pay. Uncle Sam lights his coasts and says in effect to all who go down to the sea in ships, "The light I give you for your safety is emblematic of this land — it is free." Just how big the establishment must be is realized more easily by considering the enormous size of coast line than in any other way. Measured in steps of thirty miles it is huge; measured in steps of three miles, which go into and out of a multitude of bays, coves, shelters, inlets, etc., it is enormous. The big it really is. To protect such a coast line requires an infinite variety of warning devices, and a great number of each. There are 1,662 lights other than the 2,837 so-called minor lights, 53 stations on which are maintained light vessels, commonly called lightships, 479 gas buoys, and 124 float lights, a total of 5,155 lighted aids to navigation. The unlighted aids to navigation are scarcely less important and even greater in number. Five hundred and twenty-seven fog signals blare raucously in fog and mist, 50 submarine signals give their peculiar warnings, 86 unlighted whistling buoys and 237 unlighted bell buoys give their mournful notes, 2,001 daybeacons show the way and 6,488 other buoys mark channels and shoals, a total of 9,389 unlighted aids to navigation and a grand total of 14,544 aids to navigation of all kinds. These and other ' statistics here given are as of June 30, 1915. It is evident that the lighthouse establishment of the United States must require considerable money to conduct and the able efforts of a fair army of people. The appropriation for the maintenance of the service for 1916 was $5,164,030, which included $250,000 for new lighthouse tenders. Of the balance, $2,775,000 will go for general expenses and the rest for salaries and pay. American Samoan Islands Total coast line under United States Lighthouse Service Coastal rivers on which aids to navigation are maintained by the United States Lighthouse Service (Atlantic and 48,881 teen districts, each with its own inspector and force. In the Bureau at Washington and the nineteen districts, there are 123 inspectors, engineers, draftsmen, mechanicians, etc., 145 clerks, messengers, janitors and office laborers, 71 depot keepers and assistants, 1,471 light keepers and assistants, 226 laborers in charge of minor lights, 1,556 laborers in charge of post lights and buoys, 12 custodians of reservations, 1,605 officers and crews on tenders and light vessels, 278 employees of the field force for construction and repair (registered) and 305 of the same unregistered, a total of 5,792 employees. Forty-four depots are maintained in the various districts for storage and distribution of supplies, rcpsiirs to apparatus, scraping and painting of buoys, and similar purposes. Forty-six lighthouse tenders carry supplies to and from the various depots, supply lighthouses which can- not otherwise be reached with food, coal, fuel oil and supplies, put down and take up buoys, attend beacon and fog signals, and in general keep the aids to navigation where they belong and performing their duties. During the year these forty-six vessels steamed a total of 469,000 nautical miles. The fifty-three light vessel stations are kept supplied with ships from the total fleet of 66 light vessels. Thirty-five of these are steamers, 29 are sailing vessels. The service is one of warning and of aid to navigation, yet its crews have always co-operated with the Life Saving Service (now incorporated in the Coast Guard) or taken the initiative where necessary in the saving of life and property. It is merely incidental but none the less worthy of note that during the year on 143 occasions, services were rendered in the saving of life or property by employees of the service. The service publishes a great many different booklets, which include six light lists for the various coasts and rivers, buoy lists for each of its nineteen districts, a weekly "Notice to Mariners," of which almost 200,000 copies are distributed yearly, a monthly lighthouse service bulletin, for employees, etc. The ideals and esprit de corps of the service are of the highest, and the efficiency of the various crews, their pride in their work, and their determination to "keep the light burning" make of the service one which is literally the standard of the world. The Revenue Cutter Service was originally established in 1790, at the second session of the First Congress, upon the recommendation of the first Secretary of the Treasury, as the result of the need for the services of a coast patrol for the enforcement of the customs laws and an organized armed force for the protection of the sea coast, there being at that time no naval establishment. The Life Saving Service was not the creation of a single legislative act, but the result of a series of enactments dating back to 1848, which had in view the preservation of life and property from shipwreck. In 1871 a definite life-saving system was inaugurated and administered in conjunction with the Revenue Cutter Service until June 18, 1878, when Congress established the Life Saving Service as a separate organization. ing life and property along the coast, and as one of the principal functions of the Revenue Cutter Service in time of peace was to perform similar duties on the seas, the two services necessarily co-operated with and supplemented each other to a considerable extent in this work of conservation. It became apparent that closer co-ordination and increas- WITH DRY GUN COTTON ed efficiency would result from the union of both services in one organization. The result is the present Coast Guard. The duties of the Coast Guard are so many and various that its own most condensed report "requires three hundred and ten closely printed pages. It saves life at sea and assists wrecked persons. It cares for mariners in distress and boards ships and examines papers for violations of law. It seizes vessels violating the law or makes report of such violation, patrols regattas, removes derelicts, saves property, enforces neutrality, patrols for ice and protects seals. It warns vessels of danger, recovers and buries bodies cast up, fights forest fires, and fires in wharves and shipping. It helps maintain public order, apprehends law breakers and prevents suicides. It recovers stolen property, restores ALASKA lost children to parents, furnishes transportation to other branches of the public service and acts as pilot in cases of emergency. So active is this splendid service that during the year just passed there were but five days when some unit of the service was not actively engaged in wreck or rescue work and the average day's work was the rendering of assistance of some variety in more than six cases. All that a marine police patrol can do, the Coast Guard does ; all that a Life Saving Service can do, the Coast Guard does. The Coast Guard possesses 24 cruising cutters, 18 harbor cutters, and 279 coast stations. The activities of the year resulted in the saving of 1,507 lives, and the saving of vessels and cargoes valued at $11,088,730, as well as 556 cases of assistance rendered not catalogable as of either life or property. The total expenditures for both branches of the Coast Guard totaled $5,027,752.71. Other Government departments and Bureaus occasionally return a surplus to the Treasury — the Post Office has done so and the Patent Office does so regularly. But no matter how valuable in money the saving effected by other Governmental activities may be, few if any bureaus can point to so clean cut a record as this actual rescue work of property, otherwise a total loss, valued at more than twice the cost of the whole service, and throw in the lives saved of the population of a small town for good measure ! It is the business of a Coast Guard cutter to get rid of derelicts whenever they are encountered, and frequently their duty to hunt up violations, involving fines totaling $220,500. Thirty-seven race courses were patrolled, for the protection of life and property. The fur seal patrol in the North Pacific and Bering Sea is in the hands of the Coast Guard, which keeps three vessels on duty during the summer months, and two do ice patrol duty to locate icebergs and field ice in the Atlantic steamship lines, to give warnings to trans-Atlantic vessels and prevent loss of life and property. SUBMARINE MINES derelicts reported. Last year 26 were either blown up or towed to port and turned over to their owners, involving the saving of $161,000 in property and saving who knows what lives or property in preventing these obstructions to navigation from doing damage. The enforcement of the navigation Jaws led to the boarding and examination of 24,817 vessels during the year, resulting in 772 reports for law academy, located at New London, Connecticut, where, after severe competitive examinations, young men <are given a course in training which compares not unfavorably with both Annapolis and West Point, including pra'ctice cruises upon the cutter "Itasca." In addition to its other work, the Coast Guard works in conjunction with the Board of Life Saving Appliances, which considers new inven- It is not to be expected that in every case where a wreck occurs or assistance is rendered, a complete success can be had. But the proportion of lives saved over lives lost is very large. During the year just passed, 84 disasters within the scope of the service were attended with loss of life. In every such case, according to law, an immediate investigation was made, with the inspiring result that in no case was loss of life chargeable to negligence or failure of the service, but to circumstances beyond human control. It would require more pages than there are words here available to describe in detail even the more important accomplishments and activities of the Coast Guard, but the following summary perhaps repre- ing industries, the railroads ol the United States occupy the attention of a larger number of people and give employment to more men than any other industry. To consider so vast a subject in a short space it is necessary to separate it into only its most important divisions. This chapter, therefore, will deal with the railroads of the mon consent of all railroad men, into three classes. Class I. includes the 183 railroads which have operating revenues in excess of one million dollars, Class II. includes the 285 railroads which have operating revenues less than one million dollars, but more than one hundred thousand dollars, and Class III. includes the 431 railroads which have operating revenues of less than one hundred thousand dollars. various cities of the country. There are altogether in the United States 899 railroad companies. These are divided, both by the Interstate Commerce Commission and by com- The majority of the statistics discussed in this chapter are of roads of Class I. only. These Class I. roads, however, are vastly in the majority as far as mileage and importance are concerned. Of the approximately 266,000 miles of track, 229,000 of it is operated by Class I., 20,000 by Class II., and from 16,000 to 17,000 by Class III. Statistics for this chapter have been gathered from many sources, the principal ones being the reports of the Interstate Commerce Commission, the reports of the Bureau of Railway Economics, and the reports of the Bureau of Railway News and Statistics. Inasmuch as these three statistical gathering organizations frequently cover the same subject by statistics from a dissimilar number of sources, they do not always agree in detail, but, in the main, they agree in almost every particular. Four hundred and forty-eight operating companies, including all of Class I. and almost all of Class II., render reports covering 247,312 miles of track, of which 1,913 miles go through Canada and 52 miles into Mexico. Of this mileage 11,000 rights, leaving 236,600 miles as the real physical mileage of the country. On a basis of the 1914 reported population of 98,372,266 this means that for every 390 people in the United States there is a railroad mile of line. Railroad construction in this country is on the decrease rather than the increase. Eight hmidred and ninety-eight miles were built in 1915 against 1,531 miles in 1914. These figures are for main line tracks. Including auxiliary tracks, sidings, etc., 1,319 miles were built .in 1915 as against 2,120 built in 1914. This new construction was the smallest within half a century and reflects in a most comprehensive manner the effect of the industrial depression resulting from the European War on this country in 1915. Since the panic of 1893, the largest railway mileage was built in 1902, when over 6,000 miles of new track was constructed. The total track constructed since 1893, including 1915, is 81,529 miles. RAILROADS OF THE UNITED STATES The most recent official figures are those of the Interstate Commerce Commission for 1914, which gives for tne whole country a total of all tracks of 387,208 miles. This includes yard tracks, sidings, fourth, third, second and single track as well as main line mileage. The 1915 statistics, gathered by private sources make the total for the country 379,344 miles, including the same tracks as are given in the Interstate Commerce Commission figures. tives there are 301 electric locomotives operating upon steam roads in the United States. These are of all sizes, but it is of interest to note that the world's largest and must powerful freight locomotive is driven by electricity. It is used to haul trains over the Rockies from Montana into Idano and the electricity used is generated by water power. The length of the locomotive is 1121/2 feet and it weighs 284 tons. Compare this to the average weight in tons of the steam locomotives of LOCOMOTIVES Upon these miles of tracks there are running to-day upward of 65,000 locomotives. These engines possess tractive power of 2,004,321,000 pounds, a weight so inconceivable that only a comparison can make it evident. If it were possible to hang at the end of a long rope, passing over a pulley, as many huge ships as would balance the pull in pounds of these locomotives it icould require more than tircntii-onc vessels each the size ami displacement of the illfated "Luxittinid" to c<ii«tl the combined effort of the locomotives of the United States! The locomotives of the United States haul 54,378 passenger cars and 2,362,914 freight cars. These have a capacity of 94,995,821 tons, an average of 40.2 tons per car. It is interesting to look back to the census of 1902 and find that in that year the average ton capacity of a car was but 28. Of the passenger cars 10,841 are all steel construction, 4,334 steel underframe, and 39,203 cars are yet of wood construction. The total seating capacity of all passenger cars is 2,277,438, an average of 50 passengers per car. While the value of equipment, of course, varies widely with tne roads buying it and the service for which it is adapted, it may be interesting to note the prices paid for equipment. This would make the total price of a train so into box cars, flat cars, stock cars, coal cars, tank cars, refrigerator cars and others. Of tne freight cars in use in 1914 by Class I. and Class II. roads more than one million were box cars, 146,000 were flat cars, 82,900 were stock cars, 9uO,000 were coal cars, 8,500 were tank cars, 48,800 were refrigerating cars, and miscellaneous cars made up the balance of 97,000. tween engine and rear. To the average traveler the passenger car and baggage equipment is the important thing. To the country as a whole, however, the freight cars are the vital element in railroad operation. To the public all freight cars are freight cars pure and simple, but to the railroad man they are divided illustrated by a comparison of the cars abroad than in any other manner. In twenty-four countries of Europe there are 369,911 passenger cars against 54,378 in this country. In the same twenty-four countries there are 3,443,532 freight cars against 2,362,914 freight cars in the United States. Passenger traffic is apparently much more important in Europe than it is here, or perhaps it would be more truthful to say that our huge territory and vast expanse makes transportation of goods by train a more vital necessity here than anywhere else in the world. FINANCIAL The money invested in railroads, the dividends paid, the gross and net income, the wages and salaries disci ursed, form such incredible sums that only a real appreciation of the vastness of this country can make their comprehension possible. Perhaps the most amazing facts are found in a comparison of American financial statistics with those of Europe. Travelers have so dinned it into the ears, of Americans that as a nation we' are spendthrifts and extravagant that it comes with the force of a decided shock to learn how far we have beaten the older countries in railroading. According to 1914 statistics, America had 244,253 miles of railroads as against Europe's 198,554. The capital cost of European lines was $25,059,644,889, while America paid but 115,917,192,925. These figures reduce to $126,211 as the cost per mile of line for Europe, which includes not only the low cost of railroads of Norway and Sweden, but the exceptionally high costing and magnificent road beds of England. The United States figures reduce to $65,166 per mile of line. In other words, we have some thirty per cent greater mileage at some forty per cent less cost than Europe, and these are facts in face of a scale of wages double that of the European standard, and higher rates for borrowed money. CAPITALIZATION According to the "Bureau of Railway News and Statistics," 448 operating companies, covering 247,312 miles of line, of which 188,247 were owned and 59,065 miles were leased, reported a capitalization as given at the bottom of the page. NEW CAPITAL In 1914 over $300,000,000 of new capital was invested in extensions, improvements and new construction. But 1915, a year of great uncertainty due to conditions abroad, saw less than $100,000,000 similarly employed. What 1916 will show is as yet unknown, but with the tremendous increase in the business of this country and the almost unprecedented call for transportation facilities, it is scarcely to be doubted that much new financing will be arranged. When Congress appropriated $50,000,000 to conduct an inquiry into and to establish the actual physical valuation of American railroads, many uninformed people dubbed the national legislature wildly extravagant. But four years have passed, the end of the work is nowhere in sight, and it may well not arrive While no very exact figures are obtainable, it is doubtful if the present actual value of American railways can be much less than the unthinkable sum of $22,000,000,000, which would certainly not bear out any charges of over-capitalization. Moreover, official figures of valuation of railroads within certain areas, conducted by several States, go far to prove that roads are anything but over-capitalized. For instance, State valuations made in Washington (1905) gave the cost of reproduction as 194 millions, capitalization 161 millions. South Dakota (1908) cost of reproduction 106 millions, capitalization 109 millions. Minnesota (1907) cost of reproduction 360 millions, capitalization 300 millions. Wisconsin (1909) cost of reproduction 296 millions, capitalization 225 millions. Nebraska (1911) cost of reproduction 327 millions, capitalization 263 millions. New Jersey (1911) cost of reproduction 374 millions, capitalization 333 millions. WHO OWNS THE RAILROADS Railroads are owned in two ways — by those who purchase or otherwise become possessed of stock, and those who lend money to buy, build, or extend railways, by the purchase of bonds. In the final analysis, a railway is owned by its stock holders, who owe the money represented by the outstanding bonds to the bond holders, but for ordinary purposes of comparison a bond holder is a part owner of a railroad, since his interest charges have a claim on earnings prior to the stock dividend claim. An exact census of stock holders is not a possibility, for many reasons, one of them being the frequent (hourly) changes in ownership. But according to the best reports obtainable, there are some 623,000 stock holders for American railroads, a figure almost double that of the Interstate Commerce Commission for 1182 roads in 1904. It would be wearisome to report stock holders and increase for ever.y road in the United States, but those for twenty of the great roads, show- are given on page 150. Figures for railway bond holders are not obtainable, although the Comptroller of the Currency reported in 1913 that more than eleven hundred millions of stocks and bonds together were held by savings banks, State banks, private banks and loan and trust companies as assets. INCOME AND EXPENDITURE Railroad bookkeeping is so intricate a subject and railroad financing is so involved a matter, requiring experts who spend years in the work for its thorough comprehension, that only general figures can be gone into here. The Bureau of Railway Economics summarizes the income account as on page 152, including only Class I. roads. 1914 show that the huge sum of $140,531,575 was turned into the various treasuries from all the railroads, a percentage of 4.61 of the earnings. The taxes amount to $572 per mile of road, more than double the tax of 1900 and almost three times. the tax of 1890 when $199 was the tax per mile. The relative proportion of tax to earning capacity, however, has not risen so fast. In 1890 2.96 per cent of earnings were paid in taxes, while in 1914 the amount had only increased to 4.61 per cent as above. In New Jersey railroads pay $3,068 per mile of line, in South Dakota but $255. It is interesting to compare the relative prices paid for fuel and the amount expended during the last fifteen years, for the measure of fuel used is a measure of the power expended. Unofficial figures for 1915 place the cost of locomotive fuel at $215,359,532, which is considerably less than the official figures for 1914, which are $242,800,799. Fifteen years ago but $90,593,965 was paid for fuel, although the cost of coal per ton at the mine was $1.04 in 1900 and but $1.18 in 1914. The 1915 cost was less, compared with operating expenses, than at any time for fifteen years, which may indicate that the new campaign for economy of operation and coal saving has had a visible effect. journey would have been one of slightly more than 33.6 miles. According to the Interstate Commerce Commission figures for 1914. the roads only. The 32,327,466,000 theoretical passengers who were carried one mile in 1915 each paid 2,023 cents for the privilege, and the 277,232,653,000 tons of freight, also carried one mile, cost 7.38 mills per mile for the hauling ! the Bureau of Railway News and Statistics, gives the official figures for 1914 and the unofficial figures for 1915 of both freight and passenger service. were carried. Passenger trains rolled up the enormous mileage of 607,000,000 — a distance which would carry a passenger three and onequarter round trips to the sun and back again ! There were an average of 53 passengers to every passenger train, and the nine million and some passengers paid enough to make a passenger revenue of $654,000,000, more than double the revenue of fifteen years ago and at only a minute increased cost per mile, the 1900 figures being $0.0203 per mile. FBEIGHT In 1914, Class I. and II. roads moved 85,555,053 tons of the products of agriculture, 23,763,262 tons of animals, 539,255,980 tons of mining products, 108,506,272 tons of forest products, 135,175,536 tons of manufactured products, 36,519,321 tons of merchandise and 38,447,567 tons of miscellaneous freight. These statistics show the somewhat curious result that over 55 per cent of freight moved in this country is from mines and that both forest products and manufacturing products form a greater percentage of the weight moved than do agricultural products. Reducing to a unit basis official figures show that in 1914, there were 288,319,890,210 tons of freight carried one mile, equivalent to the transportation of a fleet of Lnsitanias numbering 6,864,759; in other words, an unthinkable number. of moving passengers and freight, the railways haul the mail and tht express, two activities which are at the very bed rock of modern business. The nation pays to the rail- CLASS OF FREIGHT MOVED, 1914 roads the sum of $57,973,106 yearly (1915 figures, Bureau of Railway News and Statistics) for carrying the mail, and the express companies $69,784,468 for carrying express, a figure by the way, which is declining Passengers carried 1 mile Passengers carried 1 mile per mile of line Mileage of revenue passenger trains Average number of passengers in train Average journey per passenger, miles Passenger car miles 288 319 890 OOO Tons carried 1 mile per mile of line Mileage of revenue freight trains Average number of tons in trains Typical haul of average railway, miles Mileage of revenue mixed trains Total revenue train mileage HUMAN RELATIONS If we consider the average family as consisting of three people, then there are 33,333,333 adult males in the United States. One man in every nineteen is a railroad employee. EMPLOYEES According to the official figures for 1914, there are 1,695,483 persons employed by the railroads, or 6S5 employees for every mile of line. These include for each mile of line G general and other officers, 35 clerks, 15 station agents, 66 station men, 25 engineers, 26 firemen, 19 conductors, 55 other trainmen. 23 machinists, 29 carpenters, 103 shopmen, IS section foremen, 135 trackmen, 15 switch tenders, crossing tenders and watchmen, 16. telegraphoperators and dispatchers and 99 other employees. COMPENSATION The railroads disbursed in 1914 .$1,373,422,472 to all employees. Of the employees receiving this huge sum — about what it cost to run the United States Government, including the army and navy — the general and other officers, of course, received the largest average daily compensation, of $8.40. neers, with an average daily wage of $5.24, followed by conductors, average daily wage $4.47; machinists, average daily wage $3.27; firemen, average daily wage, $3.22 ; trainmen, average daily wage, $3.09, down to trackmen with an average daily wage of $1.59. It is a peculiar commentary on the disproportionate relation between responsibility and pay, to learn that the average daily wage of carpenters in railroad work is $2.66 and that of telegraph ope- rators and dispatchers but $2.56. According to well digested statistics, in 20 years the pay of engineers has increased 45 per cent, firemen 58 per cent, conductors 47 per cent, other trainmen 63 per cent. The average pay per year of railroad employees of all classes is $825, with a road passenger engineer averaging over $2,000, a road passenger fireman averaging over $1,200, and a road passenger conductor averaging over $1,700 per annum. Altogether twenty-two classes of employees receive over $1,000 a year. FOREIGN PAY The question is of intense interest to the general public, because of the effect upon the public of railroad labor dissatisfaction, and the economic effect of strikes. Without going into any controversy between employees and roads or in any way taking sides, it is nevertheless interesting to compare conditions here with those abroad. In this country, let it be noted, the ratio of compensation paid employees to gross earnings is 43 per cent. The ratio of compensation of employees to the operating expenses is 61 per cent and the total ratio of all expenses and taxes to gross earnings is 75 per cent. Now compare with the table on page 158. ACCIDENTS The American people have become so accustomed to frightful railroad accidents that they have accepted largely without question the statements too often made that no rail- roads are so unsafe as those of the United States. In the year 1915, 325 railroad companies operated 161,948 miles of line, according to the Bureau of Railway News and Statistics, with absolutely no fatalities to passengers in train accidents. This mileage is very nearly that of Europe excluding England. To carry 18,083,050,000 passengers a mile and kill none of them is a real record. In 1891 the United States had 161,275 miles of road, carried 531,183,998 passengers and killed 110 of them. In 1915, roads operating a greater mileage, with 40 per cent more tra3ic and double the freight traffic, killed none. Three companies have a flawless record for twelve years, 23 for eleven years, 39 for ten years, 48 for nine years, 63 for eight years, 77 for seven years, 87 for six years, 107 for five years, 136 for four years, 178 for three years, 232 for two years, and 11 companies in 1915, 23 in 1914, and 15 in 1913 killed only one passenger each. On all roads and in all ways. there were 196 passengers killed and 10,279 injured in 1915. Employees on duty were killed to the number of 1,594 and 38,060 were injured. Two hundred and fifteen employees not on duty were killed and 840 injured, and trespassers, persons not trespassers but not connected with or traveling upon railways and railroad industrial jaccidents not involving train operation made up the t Census 1913, latest reported. of 1915, the method is simple enough. As there were 389,487,542 passengers carried a mile in safety for every one killed in 1915, merely divide that number by the miles of your journey to find your proportionate chance. Thus, if you happen to be going a distance of 389 miles, your chances are just one in a million of being killed. Ask any accident insurance company what the hazards are in walking a city's streets and see how safe American railroads really are ! LINEMAN velopment and the statistics given include not only city and suburban but interurban electric roads. The authority is the United States Census for 1912, which provides the most recent facts obtainable for the industry. Nine hundred and seventy-five operating companies control 41,064 miles of track. Of this mileage 38,958 miles are for overhead trolley, the balance being conduit and all other forms of electrical propulsion including storage battery and third rail. roads 16,365 miles. In 1912 these roads carried 12.135,341,716 passengers. Not all these produced revenue, 2,423,918,- 025 being carried free. The street railways possess 94,016 cars, of which 76,162 are passenger cars, 7,794 are express, freight, mail and baggage cars, and 10,060 work cars, snow plows, ployees of all sorts have a pay envelope holding $200,890,939 per year, and it is worthy of note as showing the tremendous demand for this variety of transportation that the number of people so employed was 100 per cent greater in 1912 than in the previous census of 1902. The gross income of the 975 companies in 1912 was $585,930,517, of which $51,650,117 was paid out in dividends. It is interesting to note, in view of the agitation for municipal ownership and the cry continually going up that street railways make huge sums of money by crowding cars, that the average passenger revenue is 5.27 cents, of which 3.49 cents must go for operating expenses. The greatest street railway mileage is in New York State, which possesses 4,605 miles against 4,117 in Pennsylvania and 4,069 miles in Ohio. The least mileage is in New Mexico, which possessed 10.6 miles in 1912, followed by Nevada with 11.27. close and intimate touch with its people as the Pest Office Department. No function of our government is more important ; indeed, our whole commercial life is bound up with the Post Office, and a failure of the mail service would mean a domestic tragedy compared to which a state of war would be trivial. York. Boats, stage-coaches, pony express — the means of transportation available meant delays, uncertainty and expense. To-day two cents will carry an ounce of letter to the Philippines, to Alaska, to Porto Rico, to Canada, to Mexico, to Great Britain and some countries of Central and South America, and five cents will take half an ounce anywhere in the civilized world. THE AUTO IS A SPEEDY COLLECTOR These facts, generally recognized by common consent, have been enacted into laws governing the mail service which make "U. S. Mail" sacred service a national pride. This is not the place for a historical resume of the service since its formation by the Continental Congress, but a word or two of the development of the system may not be out of place. In 1792 it Cost seventeen cents to send a letter the distance between Boston and New Beginning with a pony express for letters only, the Post Office Department has extended its activities to meet the needs of advancing civilization until its ramifications and activities, while clearly defined, have broadened far beyond the mere carrying of letters. First of these broadening horizons was the registry system by which loss of valuables is practically negligible. City Delivery in all large cities has saved literally billions of dollars worth of time. "Special De- livery" has saved special time when special time is of great value — and at a minimum cost. This was introduced in 1885— the faint forerunner of another system of delivery which has had most tremendous and far-reaching effects. This, of course, is Rural Free Delivery — the familiar "R. F. D." which has so altered Country living conditions as to make them unrecognizable to those who sidered to have been spent for two cent stamps, then there was purchased and presumably used in 1915 the unthinkable total of 12,801,850,426 two cent stamps, enough for every man, woman and child in the United States to use on 128 letters each during the year! Of course the $256,037,008.51 received for stamps and stamped paper, which was 92 per cent of the knew them best. Next came the Postal Savings system, and finally Parcel Post, so that our Post Office Department is now a banking institution, an express company, a special carrier, an insurance office, a disseminator of knowledge (second class mail privilege), and an encourager of thrift and business as well as a mere carriage institution for folded pieces of paper. The numerical facts about our postal system are fairly staggering in their size. We have (Report for year ending June 30, 1915) 56,380 post offices, exclusive of 589 in the Philippines, under War Department jurisdiction, and 14 on the Canal Zone. Post offices are slowly decreasing in number, due to the extension of the R. F. D. service, as shown in the table above. STAMPS There are no statistics available for the number of letters transported or delivered, for obvious reasons. Kut if the total money expended for stamps and stamped paper be con- SECOND CLASS MAIL Second class mail, consisting of newspapers and periodicals mailed by the publishers at the uniform rate of a cent a pound for all distances except within the county of publication, where the postage is free, amounted to 1,109,285,785 pounds. Ten Lusitanias would not weigh so much, nor would five thousand locomotives, all over the average size used to pull trains! What this Whether parcel post or second Class mail privilege, postal savings or first class mail, foreign mail or R. F. D. is most vital is hardly important here. But certainly the establishment and successful working of the parcel post system is not least important among those great made within recent years. Exact statistics of parcels carried are not obtainable. To enable the department to ascertain the growth of the service as well as its revenues and costs, periodical counts have been made and detailed information obtained at all first and second class offices and at a number of representative third and fourth class offices of the number of parcels handled, the amount of postage thereon, and the costs of the service. Statistics in the minutest detail are compiled from these data for the 50 largest offices, which represent approximately one-half of the entire • postal business. The latest count, ; from October 1 to 15, 1915, shows ' that 30,939,730 parcels were mailed at these offices, on which the postage amounted to $1,856,602.82, and the total weight aggregated 41,815,452 pounds. Tostal Service is now handling 1,000,000,000 parcels annually. During the fiscal year 18,000,000 parcels were insured, an increase of 34.78 per cent over the preceding year. The number of parcels sent C. O. D. during the year was over 4,000,000, an increase of 57.66 per cent over the number handled the previous year. leaps and bounds. Begun with eighty-two tentative and experimental routes, it now has close to fifty thousand. Its initial appropriation was $40,000, the present appropriation is $53,000,000, most of which, of course, goes to pay the 43,718 carriers, the average pay of whom is not quite $1,100 annually. In January, 1911, the United States made its Post Office Department a great bank, by beginning the Postal Savings System. By it people of small means are encouraged to save, are provided with a quick and easy means of banking, without nny red tape, are assured the safety of their money with all the resources and credit of the United States, and are given the privilege of converting savings into United States bonds without trouble, risk or the payment of premiums. On June 30, 1915, postal savings deposits aggregated $65,684,708, a gain of $22,240,437, or 51.2 per cent, compared with amount on deposit at the close of the previous fiscal year. The number of depositors increased from 388,511 to 525,414, a gain of 136,903, or 35.2 per cent. The growth of the system from the time of its inauguration on January 3, 1911, to the close of the fiscal year ended June 30, 1915, is shown in the table on page 165. posits in amounts of $20 and multiples for 21/2 per cent United States postal savings registered or coupon bonds. Postal savings bonds were issued during the year to the amount of $1,799,040. Since the beginning of the service $6,260,360 in registered and $1,046,740 in coupon postal savings bonds have been issued. Depositors born outside of the United States constitute 58.7 per cent of the total number of depositors and own $47,161,620, or 71.8 per cent of the total postal savings deposits. Natives of Russia lead with 20.7 per cent of the total postal savings deposits to their credit; follow in order natives of Italy, 14.2 per cent, Great Britain and its colonies 8.8 per cent, Austria 8.7 per cent, Hungary 4.3 per cent, Germany 4.1 per cent, Sweden 2.2 per cent, and Greece, 1.8 per cent. Other foreign-born depositors owned 7 per cent of all postal savings deposits. BAILWAY MAIL To handle this part of the subject in a paragraph is an impossibility. Railway post offices are in service on 216,439 miles of lines and travel 322,079,796 miles a year. An army of 34 officers, 114 chief clerks and 19,351 railway clerks accomplished during the year 8,644,285,506 distributions and redistributions of pieces of first-class and 5,212,698,814 dis- THE POSTAL SERVICE trlbutlons and redistributions of pieces of second, third and fourthclass matter, a total of 13,856,984,320 distributions and redistributions of pieces, exclusive of registered matter, an increase of 3.35 per cent over the previous year. Of registered matter there were handled and rehandled in transit 57,148,648 packages and cases, 1,643,657 registered pouches, and 792,950 inner registered sacks. In addition, clerks made up and dispatched 1,095,562 registered pouches and inner registered sacks ; received 94,367 pieces. Of the 13,856,984,320 pieces of mail matter distributed and redistributed, 13,854,405,564 pieces, or 99.98 per cent, were distributed and redistributed correctly. and opened 813,266 registered pouches and inner registered sacks; handled and rehandled in transit 2,391,377 registered-package jackets ; made up and dispatched 803,779 registered-package jackets, containing 5,505,412 pieces ; received and opened 722,517 registered-package jackets containing 5,047,661 pieces; handled and rehandled in transit routes, which aggregate 285,853 miles in length. All carriers travel annually 537,714,199 miles, equal to traveling around the earth 21,508 times. Should one man make this journey at the express train rate of fifty miles an hour, it would take him 1,230 years to cover the distance, supposing he never stopped to rest! The total revenues of the Post office are $287,248,165.27, which revenues are from sale of stamps and stamped paper, postage other than stamps, foreign mails, box rents, fines and penalties, receipts from unclaimed letters, money orders and postal savings. Its expenditures are listed in detail on page 168, because of the intense interest of some of the small items, and the light they throw on the size of the work. Consider, for a moment, the business which spends over a quarter of a million dollars a year in twine, which needs to buy over three hundred thousand dollars worth of mail baffs, which requires a shop to mend "bags which costs almost a hundred thousand dollars a year for the labor alone and needs over one hundred and thirty thousand dollars worth of stationery upon which to write letters about car- rying letters, and some vague notion of the huge extent of this greatest of governmental activities may be had. shown a surplus, not a deficit, and 1916 will show one. The deficit of about 12 millions for 1915 is directly traceable to the falling off in receipts due to business depression caused by the war. Additional information regarding the activities of the service may be had from the reports of the Postmaster General, reports of each of his four Assistants, report of the Solicitor's office, or the Postal Guide, a huge book of postal information sold by the Post Office to those who need its information. The officials of the Post Office should be addressed Post Office Department, Washington, D. C. It will be & signal service to our country to arouse it to a knowledge of the great possibilities that are open to it in the markets of the world. The door of opportunity swings wide before us. Through it we may, if we will, enter into rich fields of endeavor and success. In order to do this we must show an effectiveness in industrial practice which measures up to our best standards. We must avail ourselves of all that science -can tell us in aid of industry and must use all that education can contribute to train the artisan in the principles and practice of his work. Our industries 'must be self-reliant and courageous because baaed upon certain knowledge of their task and because supported by the efforts of citizens in the mills. If scientific research and the educated worker go hand in hand with broad vision In finance and with that keen self-criticism which is the manufacturer's first duty to himself, the fields will be few indeed in which American commerce may not hold, if it chooses, a primary place. Youre very truly, ready to fight if necessary. But the finest army and the biggest navy in the world cannot constitute real preparedness without the complete mobilization of the industrial resources, which must be behind them. Fortunately, such mooilization means profit and development for the country, in the absence of any war or threat of war. Industry and natural resources are strained in time of war from two great causes : it is more difficult to get supplies from abroad, and the demand for what is at hand is supernormal. With an increased demand and a possible source of supply cut off, confusion follows unless a nation is industrially prepared as to its natural resources to such an extent that an abnormal demand does not throw machinery into The natural resources of the United States are the most remarkable in the whole world. We have made some mistakes in their development, and private interests have dominated public interests in some cases. But we have seen our mistakes, corrected many of them, and are now correcting others. That this policy will continue, and that nothing will interfere with the development, conservation and proper use of our enormous natural wealth, should be the first aim of all who Some months since I sought to learn what we had with which to meet the world which was teaching us that war was no longer only between armed forces, but an enduring contest between all the life forces of the contesting parties, their financial strength, their industrial organization and adaptability, their crop yields, and their mineral resources, and that it ultimately comes to a test of the very genius of the peoples involved. To mobilize even a great army is now no more than an idle evidence of a single form of strength if behind this army the nation is not organized. An army is no longer merely so many rifles and men, cartridges and horses; but chemists and inventors, mines and farms, automobiles and roads, airships and gasoline, barbed wire and" turning lathes, railroads and weather With the exception of one or two minor minerals, the United States produces every mineral needed in industry. We produce 66 per cent of the world's output of petroleum, 60 per cent of its copper, 40 per cent of its coal and iron, and 32 per cent of its lead and zinc. Tin in small quantities is produced in Alaska and platinum in Oregon, Nevada and Georgia, Arkansas and California; but of these latter minerals, as of nickel and some others of less importance, our supply is altogether inadequate for our consumption. We can build a battleship, or an automobile (excepting the tires), a railroad or a factory, entirely from the products of American mines and forests. To replenish the soil we have phosphorus in abundance, potash is known to exist in the deposits of Searles Lake, California, which, however, is not yet commercially available, and in alunite, where it is combined with aluminium and deposits of which are found in several States ; and nitrogen can be extracted from the air by cheap hydroelectric power as is now done in Germany, Norway and elsewhere. mate are so varied that we can produce all the grains, fruits, vegetables and fibers known to the temperate zone, and some found in the semi-tropics. And to crown all these, we have water power that can be made to generate perhaps as much as 60,000,000 horse-power. Our resources are not alone physical. Our ingenuity and ability to design the machine to meet the need have been proven a thousand times, never more convincingly than in a compilation of the most necessary inventions and discoveries which the world uses. During the past fifty years the people of the United States have uttered two thirds of the revolutionary, epoch-making inventions of the world, from the telephone and the incandescent lamp to Wright's aeroplane and high-speed tool steel. Each day we issue an average of two hundred letters patent to American inventors, and the number of inventions is increasing with the years. How great a resource this characteristic might be in time of need has been amply demonstrated during the present war in Europe, which has denied us imports formerly con- sidered essential. Benzol and toluol, foundation of aniline dyes and explosives, have been produced from crude petroleum by a new process discovered by Walter F. Rittman, of the Bureau of Mines. That an increase in the amount of gasoline which is yielded by crude petroleum is also possible by the Rittman process is by no means the least of its advantages. riety of purposes, were formerly imported in large quantities, although the raw material, barytes, occurs in extensive deposits in this country. We now manufacture these salts in California, Colorado, Illinois, Pennsylvania, New York, Tennessee and West Virginia, the new industry not only meeting the domestic demand, but also furnishing large quantities of barium compounds for export, and we are substituting domestic barytes for the foreign material for all purposes. The substitution of sodium cyanide for potassium cyanide in the treatment of gold ores to the extent of more than half a million pounds in Colorado alone illustrates how the potash shortage is being met throughout the mining States. Tungsten, an absolutely essential constituent in high-speed tool steel, is being mined at more points than ever before to meet the special demand in the steelworking industry; a tin smelter has been erected to reduce Bolivian ores ; cobalt, which is a recent and valuable acquisition to the family of steel-alloying metals, is now being produced in quantity sufficient to lower the market price; American antimony is quoted in the metal market for the first time, and from Alaska alone more antimony has been shipped this year than was ever produced from American mines in any one year; cadmium, formerly imported, is now an article of export ; and in other minor details full independence of foreign supplies is being worked out. Practically all the crude platinum from Colombia and part of the New Zea- paredness than a comprehensive conservation and development of our petroleum resources. In spite of the alarmists, statistics show no immediate prospect of a coal shortage ; the total coal produced in the United States is a minute quantity compared to the supply in sight. But of petroleum we have no such comforting statistics. How much of it there is in the United States no one knows. The Geological Survey has made a maximum estimate of twenty-three billion barrels, which sounds like an inexhaustible supply. But at the rate that it is now being consumed in this country alone (!'(;.").( )00, 000 barrels a year) this does not mean an indefinite supply, and from the rapid exhaustion of some fields it is manifest that there can be no real approximation of the oil in our lands. Whatever the supply, it should not be allowed in its crude state to compete with coal as fuel. Petroleum is a priceless resource, for it can never be replaced. Trees can be grown again on the soil from which they have been taken. But how can petroleum be produced? It has taken the ages for nature to distill it in her subterranean laboratory. We do not even know her process. We may find a substitute for it, but have not yet. It is practically the one lubricant of the world to-day. Not a railroad wheel turns without its way being smoothed by it. We can make light and heat by hydro-electric power, but the great turbines move on bearings that are smothered in petroleum. From it we get the quick exploding gas which is to the motor and the airship what air is to the human body. To industry, agriculture, commerce and the ily as possible to their full capacity as a measure of preparedness for a successful peace or the prosecution of any war into which the future may draw us, are our wonderful water powers. Among the strange things done by Benjamin Franklin was to give an added and peculiar value to the ledges of granite which confine our Western streams and turn them into dam sites, useful for purposes of power generation. How many of these are on public land not yet disposed of no one knows, but we have several hundred under withdrawal which should be freed from withdrawal and turned into use just as quickly as possible ; for, as the muscle of man or horse can raise a few barrels of water from the well to supply stock or irrigate the garden patch, so can the power of the stream, turned into electricity, be used to raise millions of barrels of water to irrigate alfalfa farms or orchards. And this is now one of the most common uses of electric power in the West, and, in fact, some of the Eastern States, where irrigation is found of value. Then, too, there is that mystifying miracle of drawing nitrogen from the air for chemical use, which can be done only with great power, but is being done in Germany, Norway, Sweden, France, Switzerland, and elsewhere, by which an inexhaustible substitute for the almost exhausted nitrates of Chile has been found. This is already a great industry in Europe, and will of necessity become greater in the United States than elsewhere, because of our size and need and opportunity. To increase the yield of our farms and to give us an independent and adequate supply of nitrogen for the explosives used in war, we must set water wheels at work. Two resources of little or no value alone, but together constituting wealth, we have in abundance. Land without water is not available for agriculture ; water, master and not servant, destroys property, industry, wealth and lives. Many rivers, great potentially as sources of irrigation, in periodical overflows and floods do incalculable damage. When we have conquered our rivers and made them serve by spreading out at our will, not theirs, over the land we wish to make blossom under the beneficent influence of irrigation, we will have added to our national preparedness a factor the value of which cannot be No one can take the yearly toll of lives lost and property destroyed by the furious and unrestrained sweep of our rivers without realizing that the people of this country cannot regard themselves as owning this land, really possessing it, until they have brought these waters under subjection. And in doing this they will literally create new land by the millions of acres, land that will support millions of people as against the thousands which live upon it to-day. How these great works can be carried on calls for constructive thought, not merely on the engineering side, but more immediately upon the financial side as to those ways and means by which the lands reclaimed shall be made to bear in some degree the burden of the expense. As to the funds which will be needed, they mount into such figures as to be staggering. And I can see no hope that this work will be adequately undertaken without the Government advancing its credit and investing directly some of its own funds. We are conducting this Government from day to day out of current revenues. Only the richest of people could pursue such a policy. No private enterprise attempts it. No railroad system has been built that way. But few of the The permanent improvements which the whole people undertake are a legitimate charge against capital account, not against maintenance. A commission to devise the ways and means by which the States and private land owners and the National Government can co-operate in paying for the work done seems to me a more needed body than one which will report upon engineering methods. There are other sides to the question upon which I have not touched : the conservation and development of our twenty-two millions of children, the men and women of to-morrow ; the proper use of our forest reserves and the wise enactment and administration of laws regarding timber as well as minerals ; the commercial development of the incredibly rich territory of Alaska, without its exploitation for the benefit of the few ; the broad visioned development of inland waterways and rivers for commerce ; the problem of good gradually working out. But enough has been said to indicate that no country in the world has better material with which to work. I believe that conservation, in its broadest term, means not the mere saving of a resource against the possible future need, but making the conserved resource as widely useful to the greatest possible number in the shortest possible time consistent with the elimination of waste. It is along this highway that this nation must move, in my judgment, if it is to be economically, commercially, humanely prepared for any future, whether of peace or war, which is to be commensurate with the opportunities nature has given us, and worthy the American character. taking into consideration the number of men employed, as follows : There are about 2,500 metal mine operators, employing 175,000 men at the mines and 50,000 men at the metallurgical plants; 6,000 coal mines, employing 734,000 men at the mines and 31,000 at coke ovens. There are 350,000 men employed in the production of pig iron and steel, 100,000 men employed at 3,000 quarries, 7G,000 men employed at brick and tile works, 60,000 in the pottery and clay industry, 69,000 in glass works and 15,000 in the petroleum industry. Barring the production in 1913, the total amount of minerals produced in the United States in 1915 was larger than in any previous year, being approximately $2,373,000,000, or a gain of 12 per cent over 1914. Of the total amount produced, the metallic products represented $987,500,000 in 1915 and $691,000,000 in 1914, an increase of 43 per cent. There was a slight decrease in the total non-metallic products in 1915, as compared with 1914, the figures being $1,423,000,000 in 1914 and $1,385,000,000 in 1915. Miscellaneous metallic products Antimony, bismuth, manganese, nickel, quicksilver, radium, scrap metals, tin, titanium, tungsten, uranium and vanadium Barytes, cement, clay and clay products, fluorspar, gypsum, phosphate rock, potash ; salt, bromine and calcium chloride ; sulphur and sulphuric acid Miscellaneous non-metallic products Arsenic, asbestos, asphalt, borax, feldspar, fuller's earth, garnet, gems and precious stones, graphite, lime, magnesite, mica, mineral painty sand and gravel, slate, talc ana soapstone. The world's production of gold in 1914 was $460,000,000, of which the United States produced $94,531,800. The United States production in 1915 was about $99,000,000. Gold is produced in twenty States, California, Colorado, Alaska, Nevada and South Dakota being the largest producers. The placer minej produce about 25 per cent and the dry or silicious ores 66 per cent. The remaining 9 per cent is from copper, lead and zinc ores. The recent high prices of copper, lead and zinc have stimulated mining, and as a result there Is an increased gold production from this source. rapidly extended to large areas of low grade sands and gravels in Alaska, California, Montana, Colorado, Idaho, Oregon and Nevada. In 1904 the amount of gold produced by dredges was $2,600,000, while in 1914 it was more than $12,500,000. Improved metallurgical processes have resulted in obtaining a recovery of more than 90 per cent of the gold in the ore and made possible the profitable mining of silicious ores containing less than $3 per ton. The average amount of gold recovered per ton of ore from the deep mines of Alaska in 1914 was $2.78 ; from California, $5.46, and from South Dakota, $3.63. Any invention that decreases the cost of production increases the amount of ore from which gold may be recovered. It has the same effect as discovering new deposits. It is not possible to give an accurate estimate of the present supply of gold ores. There is ample, however, for many decades. One mine in Alaska produces 6,000 tons of ore per day and has more than 75,000,000 tons of ore reserves. This example is given to show the magnitude of the operations that are being planned and carried into actual practice. Silver The silver production of the world for 1914 was 225,000,000 ounces, of which the United States produced one third, or 7.2,444,800 ounces, valued at $40,000.000. The production of silver in 1915 was about 7 per cent less than in 1914. Three fourths of the world's silver production is derived from North America, 14 per cent from Europe and the remainder from Australia and Asia. The United States contains vast quantities of low grade complex ores containing silver, copper, lead and zinc that are now unworked because of the lack of processes by which the metals can be recovered at a profit. Investigations by Federal bureaus are in progress to determine the extent of these ores and the possibility of developing processes for treating them profitably, thus making available large supplies of silver ore. There is every reason to believe that There are twenty-five States that produce silver, of which Nevada ranks first with 15,877,200 ounces in 1914; Idaho, 12,573,800 ounces; Montana, 12,536,700 ounces; Utah, 11,722,000 ounces; Colorado, 8,804,400 ounces, and Arizona, 4,439,500 ounces. Other States produced the remainder. The exports of silver, principally to Europe, China and India, in 1914 were 51,603,000 ounces, while the imports were 25,959,187 ounces. Platinum The principal production of platinum in the United States is from California and Oregon. The total amount produced in 1915 from these two States was 741.91 troy ounces, valued at $23,538. This is an increase of 171.91 ounces over the production of 1914. There was also produced by various platinum refineries 8,666 ounces of metals from the platinum group, of which 1,587 troy ounces is probably of domestic origin. The principal source of platinum is Russia, which produced in 1914 241,200 ounces out of the world's production of 260,548 ounces. The production reported for Russia in 1915 was 124,000 ounces, while the world's production is estimated at 143,898 ounces. The imports for 1915 were about 10 per cent lower than in 1914 and amounted to 69,000 ounces, valued at $2,768,688. The United States Geological Survey and the Federal Bureau of Mines are cooperating in a general study of placer deposits in the United States with the view of devising methods whereby platinum may be recovered from the black sands, which contain appreciable quantities of this valuable metal. Some of the gold and copper ores contain platinum in such minute quantities that it is rarely detected in ordinary assaying. The bullion obtained from these ores contains sufficient platinum to make its recovery an important by-product at gold and copper refineries. Until important sources of supply are discovered in the United States this country must depend upon Russia for its needs. Iron Ore and Iron The production of iron ore in the United States in 1915 was 55,526,490 gross tons, or about 14,000,000 tons greater than in 1914, and valued at $1.85 per ton. With the exception of the years 1910 and 1913 this is the largest production. Of the total amount produced, the Lake Superior region, including Michigan, Wisconsin and Minnesota, produced 85 per cent, and the Birmingham district, Alabama, 8.5 per cent. Comparatively little iron ore is imported into the United States (1,350,500 tons in 1914), the total being about 2 per cent of the quantity mined each year. The imports come mostly from Cuba, Sweden, Canada, Newfoundland, Spain and Chile. The exports of iron ore from the United States (551,618 tons in 1914) nearly offset the imports, so that the United States is self-sustaining as far as its production of iron is concerned. In the production of iron ore the United States ranks first, Germany second, France third, Great Britain fourth and Spain fifth. The iron ore supply of the United States of commercial grade as , mined at present is 7,500,000,000 tons, one third of which is in the Lake Superior district. While this amount seems enormous, yet at the present rate of production it is not difficult to foresee the time when this quantity will be exhausted. There are, however, important factors which bear upon the prolongation of the ore reserves. Among ,these are the development of metallurgical processes whereby lower grade ores may be utilized ; improved mining methods, which will reduce waste ; the discovery of new ore deposits ; the importation of iron ore from Latin-America and the utilization of tltaniferous iron ores. The production of pig iron, including its various alloys, in 1915 was 29,916,213 gross tons, as compared with 23,332,244 gross tons in 1914. The average value at the furnace, in 1915, was $13,21 per ton. United States ranks first, followed in order by Germany, Great Britain, France and Russia. The world's production In 1913 was 78,026,869 long tons, while in 1914 it was approximately 64,000,000 tons. The imports of pig iron (138,903 tons in 1914) and the exports (114,423 tons in 1914) almost balance each other. Copper The production of copper in 1915 was 1,388,009,527 pounds as compared with 1,150,137,192 pounds in 1914, or an increase of 21 per cent. The increase since 1880 has been 25-fold. Arizona, the largest producer of copper, leads with 432,467,690 pounds, followed next in order in 1915 by Montana, Michigan, Utah, Alaska, Nevada, New Mexico and California. The output in 1915 represents about 60 per cent of the world's production. Europe produces 13 per cent, Canada and Mexico 8 per cent, South America and Cuba 7 per cent, and all other countries 12 per cent. The average price of copper for the year 1915 was 17.5 cents per pound, as compared with 13.3 cents in 1914. At the beginning of the year the price was relatively low, but started to advance until a maximum of 20 cents a pound was reached during the middle of the year. The apparent consumption of copper in the United States in 1915 was 1,043,461,982 pounds, as compared with 620,445,373 pounds in 1914. The exports of copper bars, pigs, ingots, plates and sheets during 1915 amounted to 681,953,301 pounds, as compared with 840,080,922 pounds for 1914. The advent of the steam shovel and the introduction of improved mining methods and metallurgical processes have so lowered the cost of production that ores yielding only 1.60 per cent copper are now worked at a profit. Such ore even ten years ago would have been considered as waste material. Leaching processes have been installed by a number of companies and the results obtained indicate that even lower grade ores may be worked. These improved processes are a tremendous factor In extending the life of the available supplies of copper ores. The production of refined lead in 1915 was 550,055 short tons, as compared with 542,122 tons in 1914. The value of the lead production in 1915 was $51,705,000, as compared with $42,286,000 In 1914. The increase in the production amounted to 1.3 per cent, while the value of the lead produced increased 22.3 per cent. Missouri leads in the production of lead with 195,634 tons, followed by Idaho with 160,680 tons. The next in order of production is Utah with 106,105 tons, followed by Colorado with 32,352 tons. The other States produced small amounts varying from a few tons to 4,000 or 5,000 tons. The Imports of lead for 1915 amounted to 51,496 tons, as compared with 28,338 tons in 1914. The price of lead at the beginning of 1915 was 3.08 cents per pound, while at the close of the year It was 5.40 cents. The average New York price was 4.7 cents per pound, as compared with 3.9 cents in 1914. Under ordinary commercial conditions, about 40 per cent of the lead is used in the manufacture of white lead, 15 per cent for pipes, 7 per cent for sheets, 10 per cent for shot and the remainder for exports and other purposes. The normal exports of lead about equal the lead' produced from foreign ores. However, the exports of domestic lead in 1914 were 58,722 short tons and 87,092 tons in 1915, while no domestic lead was exported in 1913. Lead ores are mined in twenty-two States and the deposits are sufficiently large that the United States occupies the enviable .position of having enough lead to meet all demands. The world's production of zinc is slightly over 1,000,000 tons per year, of which in 1915 the United States produced 489,519 short tons, as compared with 353,049 tons in 1914, representing an Increase in domestic production of 39 per cent. The value of the spelter produced during 1915 was $121,401,000, as compared with $36,011,000 in 1914, representing an increase of 237 per cent. The exports of domestic spelter for 1915 amounted to 117,786 tons, as compared with 64,807 tons in 1914 and 7,783 tons in 1913. Illinois, Kansas and Oklahoma are the principal States in which zinc smelting is carried on, the amount smelted in each State in 1915 being as follows : Illinois, 159,958 tons ; Kansas, 100,983 tons ; Oklahoma, 109,208 tons ; with 118,930 tons apportioned among the other States not enumerated. Many of the smelter plants were increased In size during the year, while a number of new smelters were constructed. The number of retorts in operation at the beginning of 1915 was 113,914, while at the end of the year they had been Increased to 154,898. The price of spelter in January, 1915, at St. Louis was 5.5 cents per pound, while in June, 1915, it had reached the phenomenal price of 26.5 cents per pound. The average price for prime Western spelter at St. Louis was 14.2 cents per pound. Ores of zinc are widely distributed in commercial quantities in nineteen States. Missouri is the largest producer, leading with about 40 per cent. Montana is second, while large shipments originate in Colorado, Wisconsin, New Jersey and Tennessee. The supplies of ore are ample for all domestic needs. There are large losses in the present mining and metallurgical methods ; in fact, in most cases not over 50 per cent of the zinc in the ore is marketed as spelter, the remainder being lost in the various stages from mine to smelter. A large percentage of the zinc is used for galvanizing iron and in the manufacture of brass. About 20,000 tons of zinc oxide is used each year as filler for automobile tires, while 40,000 tons find a market in the paint industry. Aluminium The production of bauxite, the raw material from which aluminium is made, was 297,041 long tons in 1915, valued at $1,514,834, an increase of 35 per cent in quantity and 41 per cent in value compared with 1914. Arkansas produced about 90 per cent of the domestic > bauxite, while Georgia, Alabama and Tennessee contributed the remainder. The consumption of aluminium in the United States in 1915 amounted to 99,806,000 pounds. The demand exceeded the supply, which, together with the curtailment of imports, caused the price to be much higher than in former years. About sixty years ago aluminium was considered a chemical curiosity, valued at $90 per pound. The total amount produced in 1883 was 83 pounds. In 1889 the total production in the United States was 75 pounds per day, valued at $4.50 per pound. In 1914 aluminium was available in large quantities at 19 to 22 cents a pound, but with the increased demand due to unsettled conditions in 1915 the price rose from 19 cents in January to 57.75 cents per pound in November. The increase in the consumption of metallic aluminium has largely been due to its lightness. The specific gravity of aluminium is 2.7, whereas brass is 3 times as great, steel 2.S times and copper 3.3 times. Aluminium also resists the action of acids and is an important metal in the manufacture of high explosives, sulphuric and nitric acids. Aluminium has no substitute, but it is available as a substitute for copper as a conductor of electricity. The manufacture of aluminium is an expensive process, inasmuch as it requires large electrical installations. An abundance of cheap water power is one of the prerequisites for the successful production of this valuable metal. The deposits of bauxite are far from being exhausted, while all clays contain from 10 to 40 per cent of aluminium oxide, which may be recovered by methods yet to be discovered. Chromic Iron Ore The production of chromic iron ore in the United States in 1915 amounted to 3,281 long tons, valued at $36,744, as compared with 591 long tons, valued at $8,715, in 1914. The domestic demand for chromic iron ore increased largely as a result of conditions abroad, whereby it was impossible to import this class of ore. California is the largest producer, while a small amount has been mined near Grant's Pass, Ore. The average production of chromic iron ore from 1901 to 1913, inclusive, was only 250 tons, while the imports during the same period averaged 39,000 tons per year, mainlj from Rhodesia Russia and Turkey. Chromium finds its principal use in the manufacture of high grade tool steel. Tool steel containing small amounts of tungsten and chromium surpasses any other known alloy as an efficient agent in machine shop practice. Antimony. — The production of antimony ores in the United States in 1915 was 5,000 tons, containing 2,000 tons of antimony, valued at $325,000. The price of antimony in 1915 was the highest known since the metal became a regular article of commerce. The average monthly price for 1914 was between 5.44 cents and 7.11 cents per pound. The price of antimony rose rapidly in 1915 until it reached 40 cents per pound. Bismuth.- — Bismuth is saved as a byproduct in the electrolytic refining of lead. The production in 1914 was 220,000 pounds, valued at $426,000. The imports for 1914 were valued at $165,208. The price of bismuth in 1915 varied from $2.75 to $4 per pound. Manganese. — Only a small amount of manganese ore was mined in 1914 in the United States, 2,635 long tons, valued at $27,377. The average price at the mine was $10.37 per ton. The imports of manganese ore amounted to 283,294 tons, valued at $2,024,120. In addition to the manganese ore there was mined iron ore containing manganese to the amount of 98,205 long tons, valued at $218,497. Nickel. — The amount of metallic nickel and nickel salts recovered from smelting plants in the United States in 1914 was 845,334 pounds, valued at $313,000. Practically all of this was saved as a by-product in the electric refining of copper. The imports of nickel amounted to $5,028,818 in 1914. Strictly speaking, nickeliferous ores are not mined in the United States. Quicksilver.- — The production of quicksilver in 1915 was 20,681 flasks, as compared with 10,548 flasks in 1914. The larger part of this production is from California and Texas. The normal price of quicksilver in 1914 was $;?S per flask. The average price for 1915 was $87 per flask. Radium. — The production of radium in 1915 was 6 grammes, as compared with 22.3 grammes in 1914. The United States has the largest known radium deposits in the world, but the principal market for radium is in Europe and on account of the war the demand ceased and hence the production was curtailed. Radium occurs in minute quantities in pitchblende and caruotite. Radium as metal has been isolated but few times. It is ordinarily recovered as a hydrous sulphate, chloride or bromide. Its prin- cancer. Scrap Metals. — The amount of secondary metals recovered from scrap, sweepings, etc., in 1915, was $114,304,930. Tin. — Only a small amount of tin ore (155 short tons in 1914) is produced in the United States. The majority of this production is from Alaska and contains about 60 per cent metallic tin. Titanium. — The production of titanium ore (rutile and ilmenite) in the United States for 1915 was 250 tons, valued at $25,000 and $30,000. Rutile and ilmenite are used in the manufacture of ferrotitanium, employed in making steel and cast iron. Tungsten. — The production of tungsten in the United States in 1915 was the largest on record, being about 2,165 short tons, containing 60 per cent of tungsten trioxide, valued at slightly more than $2,000,000. The production during the first six months of 1916 was in excess of 3,000 tons. The price of tungsten ore the latter part of 1914 was $9 per unit. In the fall of 1915 the price had advanced to $48 per unit. The price of metallic tungsten rose from $1 a pound early in the year to $8 a pound in December. The principal sources of production are California, Colorado and Arizona. Its principal use is in the manufacture of tungsten high speed tool steels. Uranium and Vanadium. — The carnotite ores produced 23.4 tons of uranium oxide and 635 tons of vanadium oxide in 1915, as compared with 87.2 tons of uranium in 1914 and 435 tons of vanadium in 1914. The production of coal in the United States in 1915 amounted to 531,619,487 short tons, an increase of 3.5 per cent over the amount produced in 1914. Of the total production 442,624,426 short tons, valued at $502,037,688, was bituminous coal and lignite, and 88,995,061 short tons, valued at $184,653,498, was Pennsylvania anthracite. Pennsylvania ranks first as a coal producing State, followed by West Virginia, Illinois, Ohio and Kentucky. The total number of men employed in the coal mining industry in 1915 was 734,008, employed on an average 209 days. The United States ranks first in the world's production of coal, followed by Great Britain ranking second, with Germany third. Much of the mining in the last fifty years has been carelessly done and enormous quantities of coal have been left in the ground and in such condition that it is doubtful whether it may ever be recovered. During each year for every 500,000,000 tons produced there is wasted or left underground at least 250,000,000 tons, thus representing an average recovery of only 66 per cent. Under the best current practice with improved mining methods many of the mines are now recovering 85 to 90 per cent. Of the total amount of energy in coal not over 11 per cent is effectively utilized. The available coal supplies of the United States are estimated as 4,231,352,000,000 short tons, and represent about 51 per cent of the known deposits of the world. Estimates have been made, varying from 100 to 4,000 years, as to when our coal supplies will become exhausted, but it is safe to say that improved mining methods and more efficient utilization of the heat units in the coal will do much toward extending the period of depletion until some other source of heat and energy will be found. Coke. — About two thirds of our coke is made by the bee hive process, which wastes enormous quantities of gas, tar, ammonia, benzol and other products. The installation of by-product ovens has increased rapidly and is turning into profits and dividends large quantities of the by-products wasted in the bee hive process. The recovery of the coal byproducts places at the disposal of chemists and manufacturers a quantity of material from which dyes and explosives may be manufactured. The production of coke in the United States in 1915 .was 41,581,150 short tons, an increase of 7,025,236 tons (20 per cent) as compared with 1914. The number of bee hive ovens in operation in 1915 was 48,766 and the number of by-product ovens was 6,346. There were a large number of by-product ovens brought into use and all ovens were operated nearer full capacity (303 days) than in the previous year (286 days). The number of men employed at coke ovens in 1915 was 31,060. Coke Oven By-products. — The value of coke oven by-products was $29,824,579 in 1915, as compared with $17,500,000 in 1914. The increase in benzol products was the most interesting feature of the year in the coke industry. The value of this product rose from less than $1,000,000 in 1914 to more than $7,760,000 in 1915. In 1914 there were fourteen benzol plants, controlled by one company. In 1915 sixteen additional coke plants were equipped with benzol apparatus. The benzol products, including toluol, in 1915 amounted to 16,600,657 gallons. The amount of toluol produced in 1915 was 623,506 gallons, valued at $2.45 per gallon. The amount of tar obtained from coke ovens in 1915 was 138,414,601 gallons, valued at $3,568,384. The total value of ammonia obtained and sold was $9,867,475. Petroleum The total quantity of crude petroleum placed on the world's marKet in 1915 amounted to 426,892,673 barrels, or 7 per cent more than in 1914, making the production in 1915 the greatest on record. Of the total amount produced, the United States leads with 281,104,104 barrels, or 65.85 per cent of the world's production. Russia follows with 16.06 per cent, with Mexico third with 7.71 per cent. Petroleum was first produced in this country commercially in 1859. The imports of petroleum and petroleum products for consumption in the United States were practically negligible until 1911. The total value of crude petroleum products and ozokerite imported for consumption in the United States in 1914 was $12,300,000, of which 17,200,000 barrels was crude petroleum from Mexico, valued at $11,500,000, or 93 per cent of all imported petroleum products. The total exports of crude petroleum and liquid products of petroleum amounted in 1914 to 53,334,134 barrels, valued at $140,000,000. The growth of the petroleum industry in the United States has been rapid and has resulted in the invention of new processes and devices whereby it has been possible to increase the quantity and reduce the price of many of the petroleum by-products. The Bureau of Mines has been instrumental in the development of processes whereby the production of gasoline from crude oil may be almost doubled, and the same bureau is also devising methods for the prevention of waste in drilling for petroleum and its storage in tanks. At the present rate of consumption of 250,000,000 barrels per year, the now available supplies will be practically exhausted within a quarter of a century. However, the increasing price of petroleum, more efficient utilization and the prevention of such large waste as is now noticeable will tend to prolong the life of the fields many years beyond the above estimate. Oil shale deposits in Colorado and Utah furnish 10 to 60 gallons per ton of rock and may become an important source of petroleum as the present supplies become depleted. Natural Gas The production of natural gas in 1914 was about 592,000,000,000 cubic feet, valued at more than $94,000,000. In 1885 the value of natural gas utilized in the United States was $4,857,000. Of all of the fuels produced in the United States probably the greatest waste and loss is in natural gas. As a fuel it is easy to handle ; is clean, and where available is replacing all other fuels. The waste in its use, however, has been excessive, while the waste in its production is even still greater. It is estimated that in one State alone more than 250,000,000 cubic feet of gas is wasted daily, while in another field at least 400,000,000 cubic feet of gas Is turned into the atmosphere each day. Investigations by the U. S. Geological Survey and the Bureau of Mines are being conducted for the conservation of this valuable fuel both in its production and in its method of use. Barytcs The production of barytes in the United States in 1915 was 108,547 short tons, valued at $381,032, as compared with 1914, when the production was 52,747 short tons, valued at $155,647. The increased production in 1915 was largely due to imports from Germany being cut off. The principal States producing barytes follow in order of production : Missouri, Georgia, Tennessee and Kentucky. The deposits in these States are sufficient for domestic needs. The mineral, however, is not as pure as the imported product, so that the best utilization of these deposits will result from improved methods of bleaching and purifying the raw material. Cement In 1880 there were produced in the United States 85,000 barrels of Portland cement, while in 1915 the production was 86,891,681 barrels, valued at $74,756,674. The average price at the factory has decreased from $3 per barrel in 1880 to 86 cents per barrel in 1915. The wonderful development of the cement industry in the United States dates from the introduction of the rotary kiln fired with powdered coal in 1895. The United States imports comparatively little hydraulic cement, amounting to less than 100,000 barrels a year. Twenty years ago the imports of cement were more than 33 per cent of the domestic product, whereas in recent years they are less than 0.1 per cent. There is little or no need to import any ordinary cement, for all parts of the country are well supplied with the raw material and are not dependent upon any foreign source. The annual exports of hydraulic cement slightly exceed 4,000,000 barrels, or nearly 5 per cent of the production. Clay and Clay Products Clay. — The United States possesses immense quantities of clay, which are both suitable and available for the manufacture of clay products. In 1914 the production of raw clay (not included in the pottery or brick and tile business) in the United States was valued at $3,756,568. The closing of imports of clay from Europe on account of the war has resulted in an increased demand for high grade fire clay to replace the imported material. While many of the American clays contain a small percentage of iron, a process of eliminating the excess iron has been devised and successfully used in making some of the undeveloped clays available for higher uses. The great achievements of the clay working industries in the last half century are due to the use of Americanmade machines ; the establishment of ceramic schools ; the advertising campaigns carried on by the manufacturers of clay products, and the improvement in the quality of wares. Pottery Products. — The value of the pottery products produced in the United States in 1915 was $37,289,456, as compared with $35,398,161 in 1914, an increase of 5 per cent. With the exception of white china, all of the pottery products increased in value in 1915 as compared with the previous year. Ohio is the leading pottery State, its principal product being white ware, the output of which in 1915 was valued at $10,184,834, or nearly two thirds of the State's production, which was $15,894,597, or almost one half the total white ware production of the United States. New Jersey ranks second in the value of pottery products, West Virginia third, New York fourth, Indiana fifth and Pennsylvania sixth. The value of the imports of pottery was $6,628,086, or $1,770,507 less than in 1914. The decrease in the imports was largely due to commercial conditions in Europe. The exports from domestic production amounted to $563,452 and re-exports from foreign imports $94,705. Brick and Tile. — The brick and tilo industry forms about 78 per cent of the clay products and in 1914 amounted to $129,588,822, as compared with $143,296,757 in 1913. Ohio, as in the pottery business, leads in this industry with $21,815,392, followed by $20,100,495 for Pennsylvania. Other important States in order of production are Illinois, New Jersey, New York, Missouri and California. Fluorspar The production of fluorspar in the United States in 1915 was the largest on record with a total of 136,941 short tons, valued at $764,475. In 1883 the production was only 4,000 tons. In 1915 there were imported into the United States 7,167 tons, valued at $22,878, compared with 10,205 short tons, valued at $38,943, in 1914. The principal imports are from England. The increased production of fluorspar in 1915 was taken care of by the great demand for its use in the manufacture of steel. The American deposits occur in Illinois, Kentucky, New Mexico, Colorado, New Hampshire and Arizona, and are ample to supply domestic requirements in case of emergency. The American product is of much higher grade than the imported material. There is need for an improvement in mining methods and processes for its preparation for market. Gypsum The amount of gypsum produced in the United States in 1915 was 2,447,611 short tons, valued at $6,596,893. Practically one fourth of this production is from New York, with Iowa, Michigan and Ohio following next .in order. The gypsum beds in these States are large, while many of the Western States contain immense beds that have not been worked. There were 77 active quarries and 69 calcining plants in operation in 1915. Phosphate Rock The production of phosphate rock in the United States in 1915 amounted to 1,835,667 long tons, valued at $5,413,444. "The 1915 production showed a decrease of 898,376 long tons as compared with the production in 1914. The decreased production was the result of conditions in Europe, whereby exports were not as large as in previous years. Shipments to Germany, which hitherto has been a large consumer, have practically ceased. As a result mining operations were either curtailed or suspended entirely. The principal States producing phosphate rock are Florida, Tennessee and South Carolina. While the progress toward more efficient mining and milling methods has been great in recent years, yet the waste is much greater than it should be. The phosphate deposits are large in the South Atlantic States and in the far West, especially Idaho, Utah, Wyoming and Montana. They are in close proximity to smelting centers where there is an abundance of raw material for the manufacture of sulphuric acid, which is so essential in converting the insoluble rock to a soluble salt. Phosphate rock finds its principal use in the manufacture of fertilizer and for this reason it is of vital importance to everybody. It has no mineral substitute, hence the deposits should be conserved by their efficient utilization. Potash The production of potash salts in the United States in 1915 was valued at $342,000, which, while small, indicates the possibility of establishing a domestic potash industry. The imports of refined potash salts in 1915 amounted to 170,555,450 pounds, valued at $3,765,224, or slightly more than 25 per cent of those in 1913. Taking all potash salts together, the quantity imported in 1915 was about one tenth of that under LIGHTNING AT TITLSA, OKLA. normal conditions, when the total imports amount to about $15,000,000 annually. The imports of potash salts are almost exclusively from Germany. Experimental work on potash salts from different sources was active during the year and Government bureaus are using every effort to discover new sources of these valuable salts and methods for their production. The following possible sources are being investigated: (a) Saline residues; (6) natural and artificial bitterns; (c) alunite and similar minerals; (d) potash bearing feldspars; (e) greensand marls, and (/) organic sources, as seaweed, molasses residues, etc. Salt, Bromine and Calcium Chloride The amount of salt marketed in 1915 was 38,231,496 barrels, valued at $11,747,686, an increase in quantity of 9.8 per cent and in value 15.2 per cent as compared with 1914. In 1915 the United States produced 99.2 per cent of the salt used, hence no need for importing this staple commodity. Bromine is produced in connection with the manufacture of salt in Michigan, Ohio and West Virginia. The total amount produced in 1915 was 855,857 pounds, valued at $856,307. The high price of bromine in 1915 was due in part to the larger demand from abroad, where it is reported to be used in making asphyxiating gas. Calcium chloride is one of the byproducts of the natural brines of the Ohio Valley. A large amount of this salt is being wasted at present and no doubt new uses will be found which will stimulate its recovery. Sulphur and Sulphuric Acid Sulphur. — The principal production of sulphur in the United States is from the sulphur wells of Louisiana and Texas. The production of sulphur in 1914 was 327,634 long tons, valued at $5,954,236. The United States produces sufficient sulphur for domestic consumption and is now able to compete with Italy, which ranks second. In 1909 the exports of sulphur amounted to 37,000 long tons, while in 1914 98,153 long tons were exported, valued at $1,807,334. In 1914 26,135 tons were imported. The mining of sulphur in Louisiana is by the Frasch process, whereby superheated water is forced into the sulphur beds. The hot Abater melts the sulphur, so that it is pumped to the surface in a molten condition. Sulphuric Acid. — The most important chemical manufactured in the United States is sulphuric acid, the raw material for which is abundant in the form of native sulphur, pyrite and sulphur fumes from metallurgical plants. The production of sulphuric acid in the United States in 1915 was 3,868,152 short tons, valued at $29,869,080. Sulphuric acid is an important item in the fertilizer industry and in the manufacture of explosives. The manufacture of sulphuric acid is now becoming one of the important by-product processes in connection with the metallurgy of copper, whereby the sulphur fumes from the sulphide ores may be collected and converted into acid. This is being done on a large scale in Tennessee, and there are a number of important copper smelters in the West where thousands HYDRAULIC MINING of tons of sulphur are wasted each day, all of which could be converted into sulphuric acid and become a source of profit, instead of being a detriment to growing vegetation, as is the case at present. Arsenic. — White arsenic is recovered as a by-product from some of the copper smelters. The total production in 1914 was 4,670 short tons, valued at $313,147. Aftbestos. — The production of asbestos in the United States in 1915 amounted to 1,731 short tons, valued at $70,952. This represents an increase of 39 per cent in quantity and 306 per cent in value as compared with 1S)14. The asbestos deposits in the United States are not extensive and for this reason practically all of the asbestos used in the country is imported, largely from Canada. Arizona, Idaho, Georgia, Call- deposits of asbestos. Asphalt. — The production of natural asphalt from mines and quarries in the United States in 1915 amounted to 75,751 short tons, valued at $526,490. The total production was about 5 per cent less than in 1914. The quantity of manufactured asphalt produced from domestic petroleum in 1915 was 664,503 short tons, valued at $4,715,583, used principally for road building, and 388,318 short tons from Mexican petroleum, valued at $3,730,436. ida produced about 75 per cent. Garnet. — Practically all of the garnet in the United States is used for abrasive purposes. The production in 1914 was 4,231 tons, valued at $145,510. Qems and Precious Stones. — The -production of gems and precious stones in the United States is insignificant as compared with the imports. The total production in 1914 was $124,651, as compared with imports valued at $19.211,084 in 1914 and $45,431,998 in 1913. Borax. — The production of borax in 1914 amounted to 62,400 short tons, valued at $1,464,400. The larger part of the borax production was from southern California. Feldspar. — The amount of feldspar produced in the United States in 1915 was 113,769 short tons, valued at $629,316, representing a reduction of about 16 per cent in the amount produced. Fuller's Earth. — The production of fuller's earth in 1915 in the United States was 47,901 tons, valued at $489,219. Six States reported production as follows: Arkansas, California, Florida, Lime. — The production of lime in the United States in 1915 amounted to 3,589,679 short tons, valued at $14,336,756, an increase of 6.2 per cent in quantity and 8 per cent in value over the figures for 1914. The number of plants in operation decreased from 954 in 1914 to 905 in 1915. Magnesite. — The majority of crude magnesite comes from California. The production in 1914 was 11,293 short tons, valued at $124,223. The imports of magnesia and magnesite amounted to $1,453,508. Mica. — The value of the mica produced In the United States in 1915 was $428,769. The average price of sheet mica was 68 cents a pound, as compared with 50 cents in 1914 and 21 cents in 1913. North Carolina produced more than one half of the total production, followed by New Hampshire, Idaho and South Dakota. Mineral Paints. — The production of mineral paint in 1914, including lead and zinc pigments, amounted to 173,557 short tons, valued at $10,451,746. Sand and Gravel. — The production of glass sand in 1914 amounted to 1,619,649 short tons, valued at $1,568,030. The production of sand and gravel for moulding, building and other purposes was 77,662,086 short tons, valued at $22,278,969. Slate. — The production of slate in 1915 in the United States was valued at $4,958,515, a decrease of 13 per cent as compared with 1914. Pennsylvania and Vermont produced more than 86 per cent of the total roofing slate, the remainder coming largely from Maryland, Virginia and New York. Exports of slate in 1915 were $46,137, as compared with $139.125 in 1914. The exports were the lowest since 1895. The imports amounted to $2,768 in 1915, as compared with $4,855 in 1914. Talc and Soapstone. — The amount of talc and soapstone produced in 1915 was 186,891 tons, valued at $1,891,582. QUABBY INDUSTRY The value of the quarry products in the United States, including granite, basalt, trap rock, limestone, sandstone and marble used for building, monumental, paving and other purposes, amounted to $77,412,292 in 1914. The granite production was valued at $20,028,019, 30 per cent of which was used in building, 23 per cent in monumental work, 14 per cent in paving and 19 per cent as crushed rock. The limestone industry is the largest, amounting to $33,894,155, of which 10 per cent is used in building and nearly 60 per cent as crushed stones, the remainder being used for paving, curbing, flagging and riprap. The marble industry is the third in size, amounting to $8,121,412, of which sixty per cent is used in building and thirty per cent for monumental purposes. Sand- By WILLIAM I. WYMAN IN 1845, the birth year of the SCIENTIFIC AMERICAN, the present patent system was nine years old. In 1836 the I'atent Office was placed on a distinct basis, the system reorganized and the examination or American method of searching patents inaugurated. The American patent system was founded under the act of 1790. Under this act the Secretary of State, the Secretary of War and the Attorney General constituted a board to consider all applications for patents". Thomas Jefferson, the first Secretary of State, was in effect the first Commissioner of Patents and the first Examiner. It is said that he personally examined into and determined the patentability of every application filed during his first years in office as head of the State Department The grant of a patent then was not only a procedure of exceeding dignity, being signed by the President, the Secretary of State and the Attorney General, but was issued with some reluctance. Only three patents were permitted to see the light of day in 1790. business of the patent system grew slowly, but steadily. From 1790 to 1802 it required but one State Department clerk to perform all the clerical work pertaining to the Patent Office, the entire records of which were contained in a dozen pigeonholes. Up to 1836, about 10,000 pat- OF PATENTS FROM 1850 TO 1910. ents were granted. In that year, the Patent Office became an independent bureau, headed by a commissioner, assisted by one examiner and six other subordinate clerks and employees. While the reorganization gave the Office a dignity and standing it did not have before, still the force provided to cope with the pressing demands of inventors does not now appear to be excessively of economy was more acute than were their gifts of imagination, decried the sheer waste entailed by an organization so extravagant in men. But applications came pouring in, and in the following year the ex- a mining corps had to be doubled by the appointment of an additional examiner, and in 1839 the position of two assistant examiners was created to keep pace with the growing business. tem was instituted, by which a search through patents and publications was made to determine the question of novelty. This act also for the first time made a positive requirement for the inclusion of a claim in the specification in the following terms : "He [the inventor] shall positively specify and point out the part, improvement or combination which he claims as his own invention or discovery." PATENT OFFICE In 1836 the erection of the Patent Office was begun ; the building was finished in 1840. This original structure forms the F Street wing of the present building. In 1845 the patent system was well on its way and the Office properly housed, with an official force of one commissioner, two examiners, and two assistant examiners. In that year, 1,246 new applications were filed, besides many Caveats, and the work was becoming too heavy for this limited force to handle effectively. This condition became and continues to be chronic. Even as early as 1850, only five years after the .founding of the "Scientific American" and but fourteen years after the reorganization of the Patent Office, American inventions were numbered among the most notable produced. In 1857, this country issued over one-third more patents than Great Britain, which at that time had a substantially greater population. In that year, HOW THE NUMBER OF PATENTS HAS INCREASED YEAR BY YEAR the United States with a population of 23,000,000 issued 2,910 patents, Prussia with almost 17,000,000 issued 48, while Russia, with 70,000,000 population, issued 24 patents. Commissioner Holt, in his annual report for that year, in reviewing the statistics, grows eloquent and philosophizes thus : "As the light of liberty waxes dimmer, so does the inventive genius flag and dull apace, until finally, amid the darkness of the political night which broods over Eastern lands, it is utterly extinguished." CAN INVENTION During this decade, the one immediately preceding the Civil war, the stimulating influence of invention upon industry became noticeably apparent. Southern New England was tending to become a gigantic workshop and the character of entire sections of New York and Pennsylvania and Ohio radically changed from agricultural to industrial communities. The invention of the sewing machine — the greatest labor-saving device of the ages— (was of itself a tremendous stimulus, and the opening up of the West through the railroad meant activity in iron production and the basic engineering industries. The reaper and the thresher made the opening up of the West profitable and the inventions in firearms, machine tools, locks and SPENCER, MASS. labor-saving devices and textile machinery initiated new industries and accelerated the growth of the country by leaps and bounds. By the time the Civil war broke upon the country, only a quarter of a century after the inauguration of the present patent system, and in spite of the pre-eminently agricultural character of her pursuits, this country gave every evidence that she was to be among the first of the industrial nations. AFTER THE CIVIL WAR The distracting period of the Civil war over, activity in enterprise increased energetically, and in the year after the Civil war closed there were filed in the office' over three times as many applications as were filed in 1861. During the war, the Bessemer process was developing, and the influence of this most stimulating of inventions, which inaugurated the age of steel and our present intensive industrial era, became felt not long after its close. Then began a period of true national expansion — the further developing of the West, with strenuous enterprise in reaching out with new railroads, building of steel mills and locomotive works — marking an inflation of energy, industry and finance, which culminated in the severe panic of 1873. The country paused for a little while and took account of stock at the great Centennial Exposition in 1876. The wonders of our material advance, practically all of which were induced by invention, such as the Corliss engine, the textile machines, woodworking tools, machine tools, the sewing machine, hydraulic machinery and various kinds of automatic appliances, were there spread out for inspection to demonstrate the ingenuity of the American inventor and the intimate relation existing between him and what was making American development. The period from 1865 to 1880 gave inkling of the dawn of a radically new era. The electrical age was prognosticated in the dynamos of Gramme, Siemens and Brush, the Bell telephone and the arc lamp. But they left no impression upon industry or the social life of the time PATENTS FOR FIVE YEARS until the next period got into swing. From 1867 to 1879, the annual number of applications filed remained stationary and averaged around 20,000 per year, but about the time specie payments were resumed, the country appeared to take on a new lease of life. In 1867, 21,276 applications were filed, and in 1879, 20,059; in the next year (1880) the number increased to 23,012, and in 1889 reached 40,575, more than double the number filed ten years before. In that decade the country literally jumped forward and inventive ingenuity reached the golden age of its activity. THE ADVENT OF THE HIRED INVENTOR The larger concerns have in connection with their patent departments or in association with them research laboratories with a corps of highly trained engineers and technical and scientific assistants. Every improvement of a patentable nature, if of proved utility or possible merit, becomes the subject matter of an application, not only for the monopoly that a patent may bring, but also as a protection in its manufacture and as a matter of record. The patent department advises the technicians whether a proposed device may be patented or whether it infringes an existing patent, and also appraises the validity and value of patents offered to the company for sale. The experimental department will try out new ideas or develop them to some conclusion. Many of the big things now come through these organizations, for frequently in the evolution of an art, an instrumentality may be so complex, require the expenditure of so much skill and money to develop and demonstrate, that only a company with large resources is able to handle the proposition. Thus, the General Electric Company took several years, plus an expenditure of a few million dollars, to develop the Curtis turbine. It is by no means uncommon for a promoter to spend over $100,000 to develop a process or ap- paratus so it will be marketable. Edison, who, if not incorporated, is a host in himself, frequently spent thousands upon thousands in investigations and has made experiments by the hundreds before he was in a position to announce results. There are some devices which are so intricate in design, notably type setting and casting machines, that anywhere from a quartec to one million dollars may be expended in construction and improvement, in trials and changes, only to prove eventually, what could not possibly be determined in advance, that it could not meet the various requirements demanded in commercial practice. Then again, the device may be simple enough, its merits sufficiently obvious, but it may require more business acumen, push and advertising to introduce it than would be required to market an article of staple and competitive character, or sometimes no character at all. A wellknown instance of this inertia on the part of the public is the case of a certain safety razor, which required prodigious efforts on the part of its promoters to eventually get the public to use what appeared to be a self-evident filling of a longfelt want. No inventor can afford to create without the protection of the patent laws, because the labor and expense he is placed under preliminary to establishing the utility of his invention becomes a fixed charge and the very means to handicap him against a piratical competitor, who can start without such a burden. granted up to that year, over 500 of which were issued in the year 1843, and apprehending a cessation of all endeavors in the field of invention, uttered this prediction in his official report : "The advancement of the arts, from year to year, taxes our credulity and seems to presage the arrival of that period when human improvement must end." The commissioner could well marvel at the astounding advances made in labor-saving devices during his own lifetime, but what would have been his mental state could he have been endowed with prophetic vision and have foreseen but a fraction of the inventive activity which has taken place in a man's lifetime from the date of his utterance? The number of patents now is over a million, the annual issue is more than three times the number of all the patents granted up to his day, and the examining corps has increased from four to almost four hundred without being able to keep pace with the ever growing tide of THE MATERIAL REWARD new work. It is estimated that the value of American manufactures attributable directly or indirectly to patentable inventions amounts to the enormous total of more than twenty billion dollars, which is about four times the value of all taxable property in the United Ellsworth made his report. It has been said that the single invention of producing steel by the Bessemer process doubled, directly or through its influence, the world's wealth in the third of a century after its introduction. More astounding are the figures relating to the electrical industries, including telephony, central station lighting and power, and electric railways, the latest figures available showing an investment in the United States alone of seven billion dollars, annual gross revenue or sale.1 From an original Daguerreotype of over a billion, in which three quarters of a million men were engaged, at an annual pay-roll of over three hundred and fifty million dollars. These industries were either non-existent in 1880 or in their incipient stage at that time. Their origins and every advance therein were directly founded on inventions, every one of which is patented and of record in the Patent Office. The activity of the different classes in the Patent Office from time to time reflects accurately the changes which constantly pass in the world of industry and the applied arts. The basic pursuit in this country always being the tilling of the soil, patents for agricultural implements have occupied a prominent position, both in numbers and importance throughout its history. The invention of the sewing machine initiated a period of great activity in a new art, while the telephone let loose a flood of inventions for adaptations and improvements. The new electro-chemical industry came into being about the middle of the eighties and patent activity with relation thereto was high at the same time. The incandescent lamp started the electric age, in whose vortex we still are, and patent concern in all things electrical is still intensive. The rise and fall of the bicycle, the wave" of interest in automatic car couplings, the first surgings of activity in aeroplane invention, and the deep concern of the great ingenious to solve the urgent non-refillable bottle problem — all these movements have been reflected in the filing of applications in the Patent Office. In recent years the automobile is establishing records, the arts relating to internal combustion motors, carbureters, gearings, self-starters, accessories, alloy steels and heat treatment of steels being specially active. . The United States has by far the proudest record In the field of invention; whether reckoning by the number of pioneer products, their ingenuity, or their far-reaching ef- SIS HIRAM MAXIM fects in the greatest diversity of fields, she easily stands in first place. Particularly in labor-saving devices does she stand foremost. No one in all history has worked so hard to save labor as the Yankee. The greatest of all labor-saving devices, the sewing machine, is his, and outside of textile machinery, practically all the great advances in this department have been of his invention, as witness the cotton gin, the reaper, shoe machinery, typewriter and typesetting machines. In the field of electricity the American shares pre-eminence with Europeans, and yet the three most signal advances in electrical application are to his credit — the telegraph, telephone, and the incandescent lamp. Since 1880 (the typewriter was invented a few years previously) no revolutionary mechanical inventions comparable to those which signaled American ingenuity previously, was devised except the typesetting machine, but in the field of electricity (incandescent lamp, trol- ley car, electric welding), optics (kinetoscope, transparent film) and air navigation (an absolutely new art) he did not remain inactive. Between 1872 and 1900, Thomas Edison had received 742 patents; F. H. Richards, 619; Elihu Thomson, 444; Charles E. Scribuer, 374; L. C. Crowell, 293; Edward Weston, 280; R. M. Hunter, 276; Charles J. Tan Depoele, 245 ; and George Westinghouse, 239. Up to 1910 Edison secured 905 patents, of which 713 were electrical. Considering all the patents that are probably pending or in course of preparation, it is estimated that the number of his inventions is greater than 2,000. It is safe to assert that he is the most prolific inventor of all time. Although Great Britain has more pioneer inventions to her credit involving fundamental operations that underlie all industry, than any other country, the only innovations of pioneer character she has contributed in the last one half century are the basic process for making steel, the steam turbine, and the cyanide process. But the steam engine, the greatest invention of all ages, is hers, and so is the Bessemer process, most negligible factor in the field of applied science, although she had previously to that date given ample evidence of her vigor in pure science. The adoption of a patent system based upon that of the United States was an extreme stimulus to iflvention, and the impetus given to inventiveness is shown by the large number of very important contributions she has devised in the last 35 years, and the increasing number of patents she has taken out in this country in recent years, now exceeding those applied for by any other foreign nation. To her sons is due the gas engine, the gasoline motor ; the crude oil engine (Diesel motor) ; the automobile; the Welsbach lamp; the tungsten lamp ; the X-ray machine ; the utilization of blast furnace gases for operation of gas engines; the superheating of steam in locomotive practice; the synthesis of indigo; the contact method of making sulphuric acid ; the Goldschmidt thermit process, and the innumerable and radical innovations in dye making, drugs, and chemicals. may be made by comparing the names of inventors prominent in the earlier periods of the country's history with those which are found frequently scattered through the later additions of the Official Gazette. Fulton, Whittemore, Bigelow, Blanchard, Hoe, Campbell, Ames, Fairbanks, Howe, Colt, McCormick, etc., testify to the complete AngloSaxon predominance of former times, while such names as Bettendorf, Mergenthaler, Pupin,. Tesla, Christensen, Doherty, Frasch, Gallagher, Conner, Monnot, Krakau, Mesta, Steinmetz, Sauveur, and Lindenthal, which are abundantly sprinkled among the names listed in recent Official Gazettes, offer proof of the leavening that is going on in all departments of American life. stood by considering that during the year 1914 there were 8,265,426 persons engaged in manufacturing or 29.4 per cent of all workers engaged in gainful occupations. Of this number, 264,872 were proprietors and firm membei-s, 964,217 were salaried employees and 7,036,337 were wage earners. With the exception of the agricultural industry, the manufacturing establishments of the United States employ more men than any other industry. With respect to the value of the products produced, manufactures rank first, the total value of the products turned out during the year 1914 being $24,246,323,000. This amount represents the selling value or prices at the plants of the products turned out and does not necessarily have any relation to the amount of sales for the year. The cost of materials used was $14,368,089,000, leaving $9,878,234,000 as the value added by manufacture. The salaries and wages paid out for the year amounted to $5,367,249,000, of which amount, $1.287.917,000 was paid to. the 964.217 salaried employees and $4,079,332,000 to the 7,036,337 wage earners. It is impossible in the short space allotted to this subject to more than indicate, in a general way, the extent of manufacturing operations in the United States. For convenience the industries are treated under the following headings: Manufactured Food Products, Textiles, Iron and Steel Manufactures, Transportation, the Electrical Industry, the Leather Industry, Paper and Printing and Publishing, Chemicals and Allied Products and Miscellaneous Industries. Detailed information relative to particular industries may be had by addressing the Bureau of the Census, Department of Commerce, Washington, D. C. Unless otherwise stated the statistics given are for the census of manufactures for 1914. SLAUGHTERING AND MEAT PACKING There were slaughtered for food in wholesale establishments during the year 1914, 7.149,042 beeves, 2,019,004 calves, 15,951.860 sheep and lambs and goats and kids and 34,441.913 hogs. The total products were valued at $1,651,765.424. The fresh meat aggregated 6,656,031,002 pounds, valued at $769.383 846, comprising: 3,658,333.660 pounds of beef, valued at $421,296,794; 194,698,880 pounds of veal, valued at $26,299,446 ; 629,232,690 pounds of mutton and lamb, including some goat meat, valued at $74.675.627 ; 1.877.099,071 pounds of pork, valued at $226,535,734 ; and 296,666,701 pounds of edible offal, dressed poultry, goat meat, and game, valued at $20.576,245. Cured meat, consisting of dry salt, pickled and smoked beef and pork, exclusive of canned meat, sausage and meat puddings, aggregated 3,020,881.494 pounds, valued at $408,000,916, and comprised 91,571.573 pounds of beef, valued at $14,395,316, and 2,929,309.741 pounds of pork, valued at $393,605,600. Canned goods, consisting of beef, pork, meat products, and other canned goods, exclusive of sausage, represented 160,798,955 pounds, valued at $26.417.624. The output of sausage was 509,151,311 pounds, valued at $68,195,522, including 74,004.380 pounds of canned sausage, valued at $9,845,669, and also some sausage in paper cartons for which figures are not available. These figures, however, do not include the output of establishments engaged primarily in the manufacture of sausage. Of lard — comprising prime steam, pure leaf kettlerendered, leaf, refined and neutral — 1.119,188,675 pounds, valued at $120,414,007, was rendered. The production of compound lard and lard substitutes was 396,397,950 pounds, valued at $33,037,467 ; of oil — comprising oleo, lard, neat's-foot, and cooking oil — 23,217,082 gallons, valued at $15,935.434 ; of raw and rendered tallow and oleo stock, 209,614,135 pounds, valued at $13,732,756; of oleo and lard stearin, 30,091,991 pounds, valued at $2,752,421 ; and of oleomargarine, 60,387,881 pounds, valued at $8,818,557. CANNING AND PRESERVING There were 538 establishments engaged in canning and preserving fish and oysters in the United States during the year 1914, the products of which were valued at $55,283,404. The total value of fish and oysters canned was $41,321,593, of which amount clams were valued at $670.363 ; oysters. $2,676,951 ; salmon, $27,633,284; sardines, $6.238,933 ; shrimp, $1,725,621 ; tuna, $1,638,675 ; and other fish, $737.766. The production of smoked or dried fish was 28,713,806 pounds, valued at $2,759,341 and was made up as follows : Finnan haddie, 4,095,693 pounds, valued at $327,877 ; halibut, 509.288 pounds, valued at $62.546; herring. 11,504,126 pounds, valued at $719,640 ; salmon, 4,248,896 pounds, valued at $638.975 ; sturgeon, 511,196 pounds, valued at $150,614; all other smoked or dried fish, 7,844,607 pounds, valued at $859,689. The output of salt or pickled fish was 156,153,589 pounds, valued at $9,200.162 as follows: Cod. 83.502.295 pounds, valued at $5,561.770; haddock, 4.947.286 pounds, valued at $218,359 ; herring, 22,150.974 pounds, valued at $668.838; mackerel, 6,224.313 pounds, valued at $519,727 ; all other salted or pickled fish, 39,328,721 pounds, valued at $2,231.468. There were 3,199 establishments engaged in the canning and drying of fruits and vegetables, the products of which were valued at $158,015.893. The value of canned and dried fruits and vegetables packed during the year was as follows : Canned vegetables. $84,413.667; canned fruits, $24,897,174; dried fruits, $34,771,912; canned soups, $7,877,057 ; other products were valued at $6,056,083. FLOUR AND GRIST MILL PRODUCTS The products of the 10,787 establishments, which did merchant grinding during the year 1914, were valued at $875,496,013. The consumption of wheat by flour mills and grist mills was 543.970,038 bushels ; rye, 12,748,135 bushels ; corn, 180,115,704 bushels; buckwheat. 5,478,045 bushels ; barley, 20,288,396 bushels ; oats, 50,227,050 bushels ; other grain, 4,277,864 bushels; alfalfa, 87.884 tons : and other material, 121,965 tons. The output for the year 1914 was as follows: Wheat flour, 116,045,090 barrels, valued at $542,051.752 ; rye flour and rye Graham, 1,926,795 barrels, valued at $7,801,413; buckwheat flour, 125,622.189 pounds, valued at $3,754,857 ; barley meal, 14,000,789 pounds, valued at $212.343 ; corn meal and corn flour, 16,327,993 barrels, valued at $54,963.301 ; hominy and grits, 870.364.453 pounds, valued at $13,767,561 ; oatmeal, 30.451.581 pounds, valued at $757,804; bran and middlings, 4.648.930 tons, valued at $104,350.655 ; feed and offal, 4,753,280 tons, valued at $137,067,959; corn oil, 301,949 gallons, valued at $152,208 ; breakfast foods, rolled oats, etc., 92,676,085 pounds, valued at $2,932,238 ; all other cereal products were valued at $2,091,922 and all other products at $5,562,000. RICE, CLEANING AND POLISHING The total quantity of rough rice milled during the year 1914 was 1,036,587,825 pounds, or 23,035,285 bushels (of 45 pounds). Of this quantity 1,025,628,075 pounds was of domestic production, and 10,959,750 pounds of foreign. The amount of clean rice obtained was 674,872.108 pounds, valued at $21,655,105. This was 65.1 per cent, by weight, of the rough rice milled. There were 31,053,118 pounds of polish, valued at $352,271, produced from rice during the year ; 99,403.200 pounds of bran, valued at $772,275 ; all other products were valued at $259,643. Thus the total value of all products derived from the cleansing and polishing of rice for the year 1914 amounted to $23,039,294. BUTTER, CHEESE AND CONDENSED MILK During the year 1914 there were 7,982 establishments engaged in the butter, cheese and condensed milk indus- try, whose products were valued at $370,818,729. The quantity of milk consumed by these factories was 8,431,632,860 pounds, costing $114,314,929. The quantity of cream consumed was 2,383,828.265 pounds, costing $160,916.828. The products, valued at $370,818,729, were divided as follows: 786,013.489 pounds of butter, valued at $223,179,254; 377,506,109 pounds of cheese, valued at $50.931,925; 884.646,761 pounds of condensed and evaporated milk, valued at $59,374.948; 21,987,911 pounds of powdered milk, valued at $2,081,607 ; 4.051,320 pounds of sugar, valued at $400,613; and other products valued at $34,850,382. The total value of the cordage and twine and jute and linen goods produced during the year 1914 amounted to $83,228,424. There were produced during the year, 487,443,356 pounds of rope and binder twine, valued at $.43,085,517; 13,244,198 pounds of cotton rope, valued at $2,539.906; 105,249,677 pounds of twine, other than binder, valued at $13,996,522; 75.875.322 pounds of yarn, valued at $8.320,186; 5,707,668 pounds of linen thread, valued at $3.409,136; 131.827,658 square yards of bags and bagging, valued at $6,440,594; 3,326,302 square yards of jute carpets and rugs, valued at $816.845; and other products valued at $4,619,718. PELT GOODS The cost of all material required in the .production of felt goods during the year 1914 was $6,824,537. The total value of the products manufactured in the establishments engaged in this industry was $13,692.765. There were produced in that year, 3.941,795 pounds of endless felt belts, valued at $4,164,186 ; 3,028.286 pounds of boot and shoe linings, valued at $1.512,783 ; 7.431,152 square yards of trimming and lining felts, valued at $1,048.583: 2.291.662 pounds of saddle felts, valued at $973,353. The remaining products, including table and piano covers, felt cloth, etc., were valued at $5,993,860. The output of finished fur-felt hats in 1914 was 2.118,634 dozen, valued at $33.603.531. The total value of the products of the fur-felt industry was $37.349,744. The total value of the products of the wool-felt hat industry in 1914 was $1,944,484, of which amount, $1,777,225 represented the value of the 381,044 dozen wool-felt hats produced. ufacture of hosiery and knit goods, the products of which were valued at $263,925,855. There were 75,227,704 dozen pairs of hosiery produced, valued at $98.136,265; 21,758,775 dozen shirts and drawers, valued at $57,523,051 ; 6,283.360 dozen combination suits, valued at $35,630.464; 2.249,142 dozen sweaters, valued at $26,195,002; 2,470,183 dozen pairs of gloves and mittens, valued at $10,519,613; 987,178 dozen hoods, scarfs, etc., valued at $3,456,326 ; 274,544 dozen bathing suits, valued at $2,033.889; 63,264 dozen shawls, valued at $713,545, and 74,901 dozen pairs of leggings valued at $313.952. In the production of hosiery and knit goods there were 3,076 sets of cards used ; 852.250 spindles ; 65.328 sewing machines and 142,240 knitting machines of all classes. COTTON GOODS The quantity of raw cotton consumed in the 1,324 establishments engaged in the manufacture of cotton goods, during the year 1914, was 2,523,500,837 pounds, costing $330,315,223. The other materials consumed were classified as follows: Cotton waste, 54,116,105 pounds, costing $3,542,631 ; -cotton yarns, 139,482,027 pounds, costing $39,793.131 ; yarns, other than cotton, 3,309,277 pounds, costing $4,793,221, and fibers, other than cotton, 4,276,476 pounds, costing $3,203.262. .The total value of the cotton goods produced from these materials was $701.152,268, divided as follows: 6,815,645,683 square yards of woven goods, valued at $488,728.054; 497.986,999 pounds of yarns, valued at $127.363.952 ; 26,507.023 pounds of thread, valued at $22.917,099, and 13,284,875 pounds of cordage and rope, valued at $2,792,125. There were 317,360,019 pounds of cotton waste, valued at $14,421,929, on hand at the end of the year. All other products were valued at $44.037,886. The woven goods manufactured were classified as follows: 248,539,379 square yards of ducks, valued at $47,921,989; 489,661,133 square yards of ginghams, valued at $36.706,542 ; 1,422,787,368 square yards of fancy weaves, valued at $131,813,609; 263,862,227 square yards of napped fabrics, valued at $24,352,020; 29.128,703 square yards of velvets, corduroys, plushes, etc., valued at $8,540,143; 75,732,241 square yards of toweling and terry weaves, valued at $9,805,232; 97,981,783 square yards of mosquito netting and similar fabrics, valued at $2,820.524; 129,357,002 square yards of bags and bagging valued at $9',705,616 ; 10.137,710 square yards of tapestries, valued at $5,411,592 ; and 4,048,458,137 square yards of other woven goods, valued at $211,650,787. OILCLOTH AND LINOLEUM The total value of the oilcloth and linoleum produced by the establishments engaged in this industry in 1914 was $25,598,361. There was a decrease of 58.9 per cent in the manufacture of oilcloth during the year 1914, over the year 1909, the last census year, but this was more than compensated for by the increase of 90.1 per cent in the amount of linoleum manufactured. The oilcloth produced was divided as follows : 7,536.379 square yards of floor oilcloth, valued at $1,483,731; 18,357,097 square yards of enameled oilcloth, valued at $2,495,255; and 59.358,872 square yards of table, wall, shelf and stair oilcloth, valued at $6.025,348. The linoleum produced during the same period was divided as follows: 33,306,669 square yards of plain linoleum, valued at $10,043,436, and 8,479,202 square yards of inlaid linoleum, valued at $4,725,837. All other products were valued at $824,754. SILK AND SILK GOODS During the year 1914 there were 900 establishments engaged in the manufacture of silk and silk goods, in which the following materials were consumed : 22,506,759 pounds of raw silk, costing $86,586,878 ; 3,080,750 pounds of spun silk, costing $7,940,156; 1.902.974 ?ounds of artificial silk, costing $3,440,54 ; 4,328,536 pounds of fringe and floss, including waste, noils, etc., costing $3,066,297; 3,852,399 pounds of organzine and tram, costing $16.687,346 ; 16,869,511 pounds of cotton yarn, costing $6,163.,240; 1,464,299 pounds of mercerized cotton yarn, costing $1,078,337; 1,987,918 pounds of woolen jimi woisted yarn, costing $2.087804; ,645,055 pounds of mohair yarn, costing $1,604,362 ; and 291,672 pounds of other yarns, costing $438,944. The total value of the finished products was $253,764.170, the various products being classified as follows : 216,033.696 yards of broad silks, valued at $137,719,564; 142,713,359 yards, valued at $96.689.801, consisting of all-silk goods and 73,320,337 yards, valued at $41.029,763, consisting of mixed silk goods ; 16,318,135 yards of velvets, valued at $8,570,022; 9,114,992 yards of plushes, •valued at $10.135,842; 477,69!) yards of upholsteries and tapestries, valued at $840,126 ; ribbons to the value of $38,201,293 ; laces, nets, veils, etc., to the value of $1.328,933 ; embroideries to the value of $33,500 ; fringes and gimps to the value of $1,025,188; braids and bindings to the value of $3,073.648; tailors' trimmings to the value of $210,741 ; military trimmings to the v.alue of $431,422 ; 659,540 pounds of machine twist silk, valued at $4,036,807 ; 744,708 pounds of sewing and embroidery Bilks, valued at $5,046.452; 157.791 pounds of fringe and floss silks, valued at $598.354 ; 1,492.999 pounds of organzine, valued at $6,325,291 ; 2.577.402 pounds of tram, valued at. $9,698,637, and 1,607,416 pounds of spun silk, valued at $4,577.058. Other products were valued at $13,516,248. There were in use, during the year, a total of 2,794,971 spindles, 85.058 looms of all kinds, and 6,826 jacquard mac nines. WOOLEN AND WORSTED GOODS The total value of all the products of the 795 establishments engaged in the manufacture of woolen and worsted goods, during the year 1914, was $379,484,379 as follows : 90,950.381 square yards of all-wool woolen fabrics, valued at $55.660,503; 222.327.115 square yards of all-wool worsted fabrics, valued at $141,778,035 ; 47.398,289 square yards of cotton-warp woolen fabrics, valued at $13.598,007; 54.067,018 square yards of cotton-warp worsted fabrics, valued at $14,897,757; 31,400,082 square yards of cotton-mixed fabrics, valued at $11,710,610; 2,176,264 square yards of all-wool flannels for underwear, valued at $880,494 ; 4,995,575 square yards of cotton mixed flannels for underwear, valued at $1,089,661; 16,092,266 square yards of domett flannels and shirtings, valued at $2,814,054; 36,196.243 square yards of linings, Italian cloth and lastings, valued at $9,804,661 ; 8,415,079 square yards of satinets and llnseys, valued at $1.535,291 ; 30,400,973 square yards of blankets, valued at $9,264.768; 8,164,672 square yards of horse blankets, valued at $2,017,782 ; 514,226 square yards of carriage cloth, valued at $443,223 ; 1,658,865 square yards of carriage robes, valued at $1,233,555 ; 121,213 square yards of woven shawls, valued at $66,365; 1,351,262 square yards of upholstery goods, valued at $1,539,381, and 3,569,709 square yards of all other woven goods, valued at $1,219,382. Woolen, worsted, merino, mohair and cotton yarns, noils and wool waste and tops and stubbing made for sale were valued at $101,137.599; all other products were valued at $5,356,615. The amount received for contract work was $5.436,636. There were In operation during the year 4,220 sets of woolen cards, 2.348.722 mule spinning spindles, 1,531.862 frame spinning spindles, 841.449 doubling and twisting spindles, 56,392 broad looms, 19.415 narrow looms, 13 hand looms, 2,294 wool-combing machines, 1,201 pickers and 165 garnet machines. BLAST FURNACES During the year 1914 there were 284 active pig-iron blast furnaces in operation. The pig-iron products of the 160 establishments operating these furnaces aggregated 23,269,731 tons, valued at $312,639.706, and the value of other products amounted to $4.919.347, making a total of $317,559,053. The' amount of Iron ore used was 43,362,817 tons, costing $150.975,741. The consumption of mill cinder, scale, scrap, etc., was 2,168,092 tons, costing $6,651,055 ; fluxing material, 11,499.685 tons, costing $11,184,378; coke, the chief fuel for smelting, 26.883,382 tons, costing $83,499.448; charcoal, 29,083,978 bushels, costing $1,683,075; and coal, both anthracite aad bituminous, 99,251 tons, costing $254,007. The smelting fuels consumed cost $85.436.530. Of the total production of 23.269,731 tons of pig-iron, 15,495.004 tons were for the use of the producers and 7,774,747 tons for sale. The pig-iron product by grades for the year 1914 was as follows : Basic, 9.465,853 tons ; Bessemer and low phosphorus, 7,883.530 tons ; foundry, 4,325,100 tons ; malleable, 730.910 tons; forge or mill, 488,172' tons ; white, mottled and miscellaneous, STEEL WORKS AND ROLLING MILLS The consumption of pig-iron and ferroalloys by the 436 establishments producing steel and hot-rolled Iron and steel manufactures as their chief products amounted to 17,060,940 tons In 1914, the cost of these materials being $248,393.208. The plants consumed approximately 10,645.000 tons of scrap, of which amount 5.065,090 tons were purchased at a cost of $59.301.614, and 5,579.422 tons were produced In the works where consumed. The consumption of Iron ore amounted to 999.459 tons, costing $4,252.087. In addition, 6,440.742 tons of steel Ingots, rails for rerolling and partly finished rolled products, such as blooms, billets, slabs, muck and scrap bar, sheet and tinplate bars, etc., produced In certain mills, were purchased by others at a cost of $131,967,265. PRODUCTS The total products of the steel works and rolling mills for the year 1914 were valued at $919.527,244. The rolled, forged and other classified iron and steel products aggregated 25,586,715 tons, NOTE HOW THE PIGS FLY TO THE MAGNET valued at $802,976,516, comprising 18,526.342 tons of finished rolled products and forgings, valued at $(.24,754,421 ; 3,408,030 tons of partly finished rolled products — blooms, billets, slabs, sheet bars, tin-plate bars, muck bar, and scrap bar — valued at $130,674.009, and 652,343 tons of unrolled steel in the form of ingots and castings, valued at $47,547.136. The finished rolled products and forgIngs produced during the year 1914 were classified as follows: Rails, 1.842,041 tons, valued at $54,009,918 ; rerolled or renewed rails, 63.671 tons, valued at $1,438.237 ; rail fastenings (splice bars, tie-plates, fish-plates, etc.), 348.947 tons, valued at $11.526,956 ; structural shapes (not including plates used for making girders), 2,083.440 tons, valued at $57.475.366 ; bars for reinforced concrete, 269.966 tons, valued at $7,751,549 ; merchant bars, 2.474,677 tons, valued at $84.407,700 ; spike and chain rods, bolt and nut rods, horseshoe bars, strips, etc., 536.575 tons, valued at $18.343,812 ; wire rods, 2.377,691 tons, valued at $61,578.145; plates and sheets. 3,699.249 tons, valued at $129,785,963; black plates, 1,011.938 tons, valued at $43.147.041 ; hoops, bands and cotton ties, 603,940 tons, valued at $19,945,078; skelp, flue and pipe, 1,960,844 tons, valued at $52,443.303; nail and tack plate, 50,302 tons, valued at $2,008,308 ; axles, rolled and forged, 89,418 tons, valued at $3.311,202 ; armor plates, gun forgings, and ordnance. 38,669 tons, valued at $19.947.893 ; car and locomotive wheels, rolled or forged, 137,895 tons, valued at 7.435.798; all other rolled products, 481,779 tons, valued at $29.689,872; and all' other forged products, 411,402 tons, valued at $19,165,900. AGRICULTURAL IMPLEMENTS The total products of the 772 establishments engaged in the manufacture of agricultural implements during the year 1914 were valued at $168.120.632. The various agricultural implements manufactured comprised 3,318,176 Im- plements of cultivation, valued at $39,632,903; 634,926 planters and seeders, valued at $12.268,156; 1,102,389 harvesting implements, valued at $40,561.472; and 140,803 seed separators, valued at $13.986,184. All other products, including parts for all classes of agricultural implements, were valued at $60,211,327. The amount received for rf pair work was $1,460,590. The total products of wire drawing establishments in 1914 were valued at $172,600,587, of which amount $166,999,888 represented the value of wire and manufactures of wire, $2.581,000 represented the value of finished products other than wire and wire products and $3.019.699 represented the value of all other products, including scrap, copperas, etc. The total quantity of steel and iron wire drawn in 1914 was 2,465,383 tons, valued at $116,215,503, and included 459.909 tons of plain wire, valued at $22,316,778; 374.478 tons of coated wire, valued at $15.949.531 ; 12,886.634 tons of wire nails and spikes, valued at $23,368,633; 33,335 tons of wire brads, tacks and staples, valued at $1,324,948 ; 343,693 tons of barbed wire, valued at $13,764,367; 52,735 tons of wire rope and strand, valu«d at $7.973,537; 411.460 tons of woven-wire fence and poultry netting, valued at $19,795,812; 22,721 tons of other woven-wire products, valued at $2,822,689; and 122,720 tons of other fabricated iron and steel wire products, valued at $8,899,208. The total quantity of copper wire drawn was i:i"i.4:"!7 to'ns. valued at $42.928.550, and included 84.921 tons of bare wire, valued at $26,206,024; 48.386 tons of insulated wire, valued at $15,709,244; and 2.130 tons of woven and other fabricated copper-wire products, valued at $1,013.282. There were also produced 39,614,500 pounds of brass wire and wire products, valued at $6,366,342; 749,224 pounds of German-silver wire, valued at $238,078; and wire of other metals and al- TIN AND TER.NE PLATE There were 31 establishments engaged in the tin and terne plate industry in 1914 whose output of coated plates amounted to 2,039.566,144 pounds, valued at $66,270,345, comprising 1,901,331.895 pounds of tin plate, valued at $60,258.024. and 138,234,249 pounds of terne plate (steel or iron plates or sheets coated with an alloy of tin and lead, known as terne mixture), valued at $6,012,321. The tin-plate product comprised 1.855,892.526 pounds of coke plate, valued at $58,450,853. and 45.439.369 pounds of charcoal plate (steel and iron), valued at $1,807,171. The value of all other products was $2,072.617, The cast-iron pipe product of 1914 comprised 1,092,208 net tons, valued at $25.391,714, consisting of 880,556 tons of gas and water pipe and fittings, valued at $19.218,006. and 211,652 tons of sofi and plumbers' pipe and fittings, valued at $6,173,708. The gas and water-pipe output was made up of 802.967 tons of bell and spigot pipe, valued at $16,228,587 ; 25.192 tons of flanged pipe, valued at $645.707 ; 12,011 tons of culvert pipe, valued at $246.527 ; and 40.386 tons of fittings, valued at $2,097,185. In addition, there were produced 26,199 tons of castings other than pipe and fittings, valued at $741.381, and products other than castings, valued at $1,441,678. During the ymr 1914 there were 138,178 steam and electric cars, valued at $165.071.427, built in the United States. Of this number, 3,558 were steam-passenger cars, valued at $45,027.083 and 131.799 were freight and other cars, valued at $110,002.456. The number of electric cars manufactured was 2.821, and their value was $10,041.888. For more detailed information relative to the construction of railroad cars, locomotives, etc.. the reader is referred to the special chapter on "Railroads of the United States." CARRIAGES AND WAOOXS AND MATERIALS The total value of the carriages and wagons and materials manufactured in 1914 was $135.792.357. There were 1.187.002 vehicles of all classes, valued at $72,283.989, including 558.402 carriages, valued at $34.193.518; 572,613 wagons, valued at $36.533.152 ; 1.287 public conveyances, valued at $325.269 ; and 54.700 sleighs and sleds, valued at $1.231.959. Other products, parts, repairs, etc., were valued at $63.508.459. There was a decrease of 25.1 per cent in the production of vehicles during 1914 over 1909. due to the inroad of the automobile into the carriage and wagon industry. This has been greater with respect to pleasure vehicles than to those used for business purposes. SHIPBni.DINO During the year 1914 there were 1,145 establishments engaged in the shipbuilding and boatbuilding industry, whose products — that is, construction and repair work done — during the year, were valued at $88,682.071. The value of work done on new vessels of five gross tons and over was $42,545,445, of which amount $36,295,758 represented the value of work done on iron and steam vessels and $6.249,687 the value of work done on wooden vessels. The value of work done on boats of less than five gross tons was $3.788.689. The value of repairs made in 1914 was $32,835,212. All other products were valued at $9,512,725. The total number of vessels of five gross tons and over launched during 1914 was 1,113 with a gross tonnage of 424.660. There were launched 126 iron and steel vessels with a gross tonnage of 242.559 ; and 987 wooden vessels with a gross tonnage of 182.101. Classified according to power, there were launched 140 steam vessels, gross tonnage 234,636 ; 427 motor-driven boats, gross tonnage 13.220 ; 40 sailing vessels, gross tonnage 2.224, and 506 unrigged vessels, fross tonnage 174.580. There were 3,06 power boats of less than five gross tons launched during the year. MOTORCYCLES, BICYCLES AND PARTS The total value of the motorcycles, bicycles and parts manufactured during 1914 was $25.486,942. There were manufactured 62,793 motorcycles, valued at $12.306,447, an increase in number of 237.1 per cent over the year 1909, and 398,899 bicycles, valued at $5,361,229. SUPPLIES There were 1,121 establishments engaged in the manufacture of electricalmachinery apparatus, during the year The output of dynamos, including parts and supplies, in 1914 was valued at $23,233,437. This includes dynamo- tors, motor-generators, boosters, rotary converters, double-current generators, etc., 8,393 in number, with an aggregate capacity of 780,009 kilowatts and valued at $5.367,895; 208,548 small directcurrent dynamos and automobile selfstarters, valued at $5,933.273 ; 9,633 direct-current dynamos, including generators for direct connection to steam turbines, with an aggregate capacity of 221,221 kilowatts and valued at $2,967,467; 2,512 alternating current dynamos, including generators for direct connection to steam turbines, with an aggregate capacity of 1,188,005 kilowatts and a value of $7.437,445. The transformers manufactured in 1914 aggregated 115,843 in number, with 2.644,794 kilowatts capacity, and were valued at $13,120,065. There were 110,177 machines of less than 50-kilowatt capacity, valued at $7,316,615 ; 4.857 speed-controlling devices, feeder-potential regulators, reactances, voltage regulators, and rectifying apparatus to the value of $9,936,343; light and power switchboards, panel boards and cut-out cabinets, valued at $8,989,111 ; batteries, storage aud primaries, and parts and supplies, $23,402,455 ; lamps, $17,350.385 ; arc lamps, searchlights, projectors and focusing lamps, $2,823,687 ; telephones, telephone switchboards, and parts and supplies, $22,815,640; telegraph apparatus, including wireless, switchboards, and parts and supplies. $2,248,375 ; electric heating apparatus, including air heaters, cooking devices, flat-irons, and welding apparatus, $4,034.436 ; electric measuring instruments. $8,786,506; electrical therapeutic apparatus, $2,653.098 ; insulated wires and cables, $69,505,573 ; electric conduits, underground and interior, $4,874,709 ; THE FIRST CENTRAL POWER STATION IN THE UNITED STATES of from 50 to 500-kilowatt capacity, valued at $2,625,414; and 809 of 500 kilowatts and over, valued at $3,178,036. The output of motors, including parts and supplies, was valued at $44,176,235. This includes 417,992 motors for industrial power and for railway use, with an aggregate capacity of 2.882.795 horsepower, and a value of $32:286,149 ; 11,880 motors for automobiles, having an aggregate horse-power of 36,858 and valued at $1,351,442; motors for fans ' to the value of $4,835,850 and miscellaneous motors valued at $1,190,564. magneto-ignition npparatus, spark plugs, coils, etc., $22,260,847 ; electric switches, signals and attachments. $6,393.551 ; carbons for furnace, lighting, brushes, battery, etc., $3,602,741 ; annunciators. $263,806 ; electric clocks and time mechanisms, $410.774; and various other kinds of electric equipment, inchiding sockets, receptacles and bases, some electric lighting fixtures, lightning arresters, fuses, circuit fittings, and unclassified electric machinery, apparatus and supplies, $44.907,658. The last item includes electric locomotives, mine and railway, of which t^ere were 900, valued at $3,720,914. THE LEATHER INDUSTRY Tnere were tanned during the year 1914, 138,547.692 hides and skins, as follows : 17,457,591 cattle hides, costing $148,751,002. 16.067,793 calf and kip skins, costing $33,117,713; 37.755.867 goat and kid skins, costing $23.916,965 ; 40,090,198 sheep and lamb skins, costing $19.247.682, and 1.250,245 horsehides, 1.095.360 kangaroo skins, 233,180 colt skins and a number of hog, pig, deer, buck, seal, dog, alligator, shark, elk, moose and other skins, costing 18,414,129. The leather products, valued at $348,956.S72, were divided as follows: 18,097.005 sides of sole leather, valued at $116,347,196; 973,591 belting butts, valued at $12.876.554; 2.943.720 sides of harness leather, valued at $21.745,808 ; upholstery — automobile, furniture and carriage — leather to the value of $14.328,358 ; bookbinders' leather to the value of $1.362,673; 8.245.964 sides of cattle side upper leather, valued at $32.939,139 ; 965.350 sides of horse leather, valued at $2,881,924 : glove leather to the value of $3,286,352; rough leather to the value of $4,511.251 ; 66,368,840 skins of upper leather, valued at $85,051,550; 7,698,452 skins of patent leather, va.lued at $15,590.812; 7,486.260 skins of fancy leather; valued at $8,775,968; 1,004,581 sides of case, bag and strap leather, valued at $5.383,255; 1.948.533 skins of chamois, valued at $925.492; and all other leather — lace, collar, saddlery, suspender, piano action leather, etc. — to the value of $21,249,116. LEATHER GLOVES AND MITTENS During the year 1914, there were 352 establishments engaged in the leather glove and mitten industry with products valued at $21.614,109. There were produced 3,082,376 dozen pairs of gloves, The production of men's gloves, mittens and gauntlets was 2,367,263 dozen pairs, valued at $15,334,605, of which 1,571,649 dozen pairs, valued at $11.286,861, were unlined ; 594,880 dozen pairs, valued at $3,584,118, were lined; and 200.734 dozen pairs, valued at $463,626, were part leather and part fabric. Of the 425,501 dozen pairs of women's and children's gloves, mittens and gauntlets, 325,530 dozen pairs, valued at $3,196,761, were unlined. and 99,971 dozen pairs, valued at $766,409, were lined. Of the 289.612 dozen pairs of boys' gloves, mittens and gauntlets, 51,797 dozen pairs, valued at $199,630 were unlined, and 237.815 dozen pairs, valued at $799,153, were lined. FOOTWEAR The 1,355 establishments engaged in the manufacture of footwear, during 1914, produced a total of 292.666.468 pairs of footwear, valued at $501,707.937. The total output of boots and shoes amounted to 252,516,603 pairs, of which 98,031,144 pairs were for men ; 22.895.719 pairs for boys and youths ; 80.916.239 pairs for women, and 48,322,395 pairs for misses and children. There were produced 2,351,106 pairs of fiber shoes of all classes. The output of slippers, not including infants' slippers and slippers made from felt or other fiber, amounted to 17.733,689 pairs. Of Ibis number, 3,666.972 pairs were for men, boys and youths and 14,066,717 pairs were for women, misses and children. The output of infants' shoes and slippers was 15,476,763 pairs. The output of all other footwear, including athletic, sporting, logging and mining shoes, sandals, and felt and other fiber slippers, was 6,939,413 pairs. PAPER AND WOOD PULP The production of wood pulp in 1914 amounted to 2,894,650 tons. In addition to the domestic production there were used 534.395 tons of imported pulp. Other materials used were as follows : 371,346 tons of rags, 1,577,845 tons of waste paper, 121.230 tons of rope, jute, bagging, threads, etc., and 309.345 tons of straw. The total value of the paper produced in 1914 was $294,355.875 and was divided as follows : 1.313.284 tons of news paper, valued at $52,942.774 ; 786,626 tons of plain book paper, valued at $58.496,626 ; 117.342 tons of coated book paper, valued at $11.605.584 ; 9.332 tons of plate, lithograph, map. wood cut book paper, valued at $588,332 ; 21,679 tons of book cover paper, valued at $2,809,377; 83,010 tons of cardboard, bristol board, card middles, tickets, etc.. valued at $5,376,434; 247.728 tons of fine paper, valued at $34,054,918. including 195.351 tons of writing paper, valued at $28.637,257; 881.799 tons of wrapping paper, valued at $49,372.753 ; 1,288,527 tons of wood pulp, straw, news and binders' board, and all other board, valued at $41,870.947; 121.598 tons of tissue paper, valued at $11,535.720 ; 14.157 tons of blotting paper, valued at $1.457,897 ; 243,908 tons of building (roofing, asbestos and sheathing) paper, valued at $9.475,733 ; 96,527 tons of hanging papers, valued at $4,488,910; and 130,459 tons of miscellaneous paper, valued at $9.890.641. All other products manufactured for sale were valued at $40,558,708. During the year 1914 there were 31,612 establishments engaged in printing and publishing, of which number 12,115 were engaged chiefly in the printing and publishing of books and pamphlets, or in job printing, 180 in the printing and publishing of music and 19,317 in the printing and publishing of newspapers and periodicals. The total value of products for 1914, of establishments printing and publishing newspapers and periodicals, was $495.905,984. The revenues of the newspaper establishments comprised newspaper subscriptions and sales, $99,541,860 ; newspaper advertising, $184,047,106 ; subscriptions and sales of periodicals other than newspapers, $64.035,230 ; and advertising in such periodicals, $71.906,976. The value of products of establishments engaged chiefly in boo'i and job work of all kinds aggregated $307,330,861. The total receipts for job printing, for the entire printing and pub- lishing industry, were $249,730,932; for books and pamphlets, $87,316,348; for bookbinding and blank books, $15,097,109 ; for electrotyping, engraving, lithographing, etc., $9,698,641 ; for machine composition for others, $5,682,098 ; for ready prints (patent insides and outsides), $1,965,210; and for all other products, $13,860,525. The receipts from music printing and publishing for the entire industry were $7,626,076. During the year 1914 there were 22,745 newspapers and periodicals published. There were 2,580 daily newspapers with an aggregate circulation of 28.436,030 ; 570 Sunday papers, with a circulation of 16,445,820; 84 triweekly newspapers, with a circulation of 549,495 ; 583 semiweekly newspapers, with a circulation of 2.483,629 ; 15,166 weekly newspapers, with a circulation of 50,454,738 ; 2,820 monthly publications, with a circulation of 79.190,838; 500 quarterly publications, with a circulation of 18.852,401 ; and 442 other publications, with a circulation of 8,946,567. CHEMICALS The value of the chemical products produced in 1914 was as follows : Acids, $30,001,364 ; alums, $3,467,969 ; bleaching materials, 94.964.403; cyanides, $2,398,674 ; plastics, $13,895.784 ; sodas, $22,616.696; sodium products, $8,280,572 ; compressed or liquefied gases, $8,097,720 ; chemicals produced with the aid of electricity, $29,661.649 ; potash and potassium salts, $4,094,927 ; coaltar products, $8,839,506 ; fine chemicals — that is, chemicals sold in the trade as chemically pure, such as ether, chloroform, etc. — $10,316.519, and general chemical products, $47,796,271. In addition to the allied products which are treated below in some detail, there were produced essential oils to the value of $2,565,361 ; refined petroleum to the value of $396,361,405 and products of wood distillation to the value of $10,236,332. DYESTUFFS AND EXTRACTS The total products of the dyestuff and extract industry in 1914 were valued at $21,341,122 and included dyestuffs valued at $7.118,528, tanning materials valued at $7,840,057, mordants, assistants, and sizes valued at $5,044,225, and other products to the value of $1,338,312. EXPLOSIVES The total production of explosives, excluding exports, in the United States during 1915 was 460.900,796 pounds, as follows : Black blasting powder, 197,722,300 pounds ; "high" explosives, 235,828,587 pounds ; and permissible explosives, 27,349,909 pounds. fregated 8,414,959 net tons, valued at 152,815,786, consisting of 4,488.565 tons of complete fertilizers, valued at $97,046,825 ; 1,116,739 tons of ammoniated fertilizers, valued at $24,344,271 ; 1,760.290 tons of superphosphates, acid phosphates, and concentrated phosphates, valued at $16,145,659 ; and 1,049,365 tons of other fertilizers, valued at $15,279,031. In addition, there were manufactured for sale other products to the value of $15,572,619, including oil, glue, grease, bone black, sulphuric acid, chemicals, etc. PAINTS AND VARNISHES The principal materials used by the 855 establishments engaged in the manufacture of paints and varnishes in 1914 were as follows : 149.968 tons (2,000 pounds each) of pig lead, costing $11,424.544 ; 887,273 gallons of grain alcohol, costing $360.737 ; 919.581 gallons of wood alcohol, costing $387.539 ; 24,025,502 gallons of linseed oil, costing $11,843,236; and 48.113,516 pounds of gum, costing 4.662,972. The total value of the products from these materials was $149,049,820 and included colors or pigments, valued at $17,407,955 ; oil paints, valued at $70,582,461 ; water paints and kalsomine, valued at $2,202,281 ; varnishes and japans, valued at $36,061,203 : fillers, including putty, valued at $3,239,174; bleached shellac, valued at $1,806,802 ; and other products valued at $17,749.944. pounds, valued at $3,697.702, was marketed (try, and 199,726,280 pounds was made into and marketed in the form of paint. The total production of lead was 61,335,290 pounds, of which 58,642,588 pounds, valued at $3,281,716, was sold as lead oxides. TURPENTINE AND ROSIN The total output of the 1,392 turpentine distilleries in operation in 1914 was valued at $20,968,684 and consisted of 26,980,981 gallons of spirits of turpentine, valued at $10.510,407 : 2,885.077 barrels of rosin, valued at $10,332,700; and dross, valued at $125,577. SOAP ments engaged in the manufacture of soap during 1914 were valued at $135,340,499. The soap products were valued at $107,030,620 and other products, including glycerine, at $29,142,533. The production of hard soaps was 2,064.228,000 pounds, valued at $104,500,542 and comprised 938.447,000 pounds of tallow soap, 42.524,000 pounds of olein soap, 111,063,000 pounds of foot soap, 169,926,000 pounds of toilet soap, 367.744,000 pounds of powdered soap, 97,746.000 pounds of soap chips, and 336.778,000 pounds of other kinds of hard soap. The production of soft soap was 57,002,000 pounds, valued at $1.697,424. In addition, there were special soap articles, such as soaps for technical purposes, and liquid soap, to the value of $832,654. MISCELLANEOUS INDUSTRIES During the year 1914 there were 347 establishments engaged in the manufacture of glass, the products of which were valued at $122,964,792. The value of building glass produced was $36,794,869. as follows : 400.998.893 square feet of window glass, valued at $17,466,756 ; 43,040,079 square feet of obscured glass, Including cathedral and skylight glass, valued at $2,417,253; 60,515,008 square feet of plate glass, valued at $14.799,646 ; 15,688,844 square feet of wire glass, valued at $1,590,934; and all other building glass, to the value of $520,280. The pressed and blown glass produced was valued at $30,130.077 ; bottles, jars, etc., $51,425,022; and all other products, $4,614,824. The consumption of gas-making fuels by the 1,284 gas companies in 1914 comprised 6.116,672 tons of coal, costing $20.872.517; 716.619,357 gallons of oil, costing $24.934.184 ; 964,851 tons of coke, costing $4.706,602; and 31,749,491 pounds of calcium carbide, costing $778,037. There was also purchased by the gas companies 28,351.074.000 cubic feet of gas, at a cost of $8,883.016, a portion of which was enriched and sold, and the remainder sold as purchased. The gas products comprise 203.730,191,000 cubic feet of gas, valued at $175,065,930, consisting of 10,509,946,000 cubic feet of straight coal gas, valued at $10,726,514 ; 90.017,725,000 cubic feet of carbureted water gas. valued at $74.516.534; 86,281,339,000 cubic feet of mixed coal and water gas, valued at $72.012.021 ; 16.601,805.000 cubic feet of oil gas, valued at $15,044,509 ; 137.964.000 cubic feet of acetylene, valued at $2,511.634; and 181,412,000 cubic feet of other gas, chiefly if not entirely gasoline gas, valued at $254.718. In addition, the gas plants ^produced for sale 114.091.753 bushels of coke, valued at $8,719,910; 125,938.607 gallons of tar, valued at $3,252,756 ; and ammonia liquors, ammonium sulphate, and hydrocarbons, valued at $1.405,540. They also sold "other products" — consisting largely of gas purchased for sale — to the value of $20.815.871. Receipts from rents and sales of lamps and appliances aggregated $10,977,774. ARTIFICIAL ICE The total cost of ammonia used in 'the manufacture of ice in 1914 was $1,529.775. There were 5,405,917 pounds of anhydrous ammonia used, costing $1,4?2.196 and 1.927.664 pounds of aqua ammonia, costing $107,579. The total value of all products for the year was $60.352.236. There were produced 17,086.400 tons of can ico, valued at $52,116,457, and 1,179.092 tons of plate ice, valued at $3,107,839. Other products were valued at $5,127,940. RUBBER GOODS The products of the 331 establishments engaged in the manufacture of rubber goods during the year 1914 were valued at $300.251,827. The production of rubber tires was valued at $146,411,692 and formed 48.8 per cent of the total value of all kinds of rubber manufactured. There were manufactured 8,020,815 automobile tires or casings, valued at $105,671,223; 7.906,993 automobile inner tubes, valued at $20,098,936 ; solid tires for motor and other vehicles to the value of $13.735,681 ; and 3,728.138 motorcycle, bicycle and Aeroplane tires, valued at $6.905.852. There were manufactured during the year 4.024.486 pairs of boots, valued at $12,647.934, and 57.211.728 pairs of shoes, valued at $37.858,222. The value of rubber clothing produced was $6.396.810 : of garden, fire, and other hose, $16.853.693 ; of rubber belting, $7.989.405 ; of rubber packing, $3,507.651 ; of druggists' and stationers' sundries, $7,- STEAM LAUNDRIES > In the year 1914 there were 6,097 steam laundries in the United States, with 149,100 persons engaged in the industry. The capital invested was $98.055,001. The cost of materials was $26,919,200 and of services, $71.764,059. The amount received for work done, which is regarded as the product of the industry, was $142,503,253. GLUCOSE AND STARCH The principal materials used in the manufacture of glucose and starch are corn, potatoes and wheat flour, the consumption of these materials in 1914 being 2,488.792.4(15 pounds, 169,878,784 pounds, and 14.198. <>49 pounds, respectively. The total value of the manufactured products was $51,676.653. Tho principal products were 620.764.347 pounds of starch, valued at $15.783,781: 847.1SO.96S pounds of glucose, including all sirups, valued at $18,541.429; 174.368,818 pounds of grape sugar, valued 'at $3,765.515; 8.S61.57!) gallons of corn oil, valued at $3,693,163 ; and 143.001.065 pounds of corn-oil cake and meal, valued at $1,829,305. Stock feed was valued at $6.690.412, and all other products at $1,373,048. and materials manufactured in 1914 was $68,769,476. The number of pianos manufactured was 325,893, valued at $56,266,362. There were 227,556 upright pianos without player attachments, valued at $31,385.881 ; 87.808 upright pianos for (or with) player attachments, valued at $20.265,514 ; 9,698 grand pianos without player attachments, valued at $4,201.302 ; and 831 grand pianos for (or with) player attachments, valued at $413,665. There were 6,493 separate player attachments manufactured with a value of $854.774. The number of organs manufactured was 42,806, valued at $6,378.312. There were 2.273 pipe organs, valued at $4,660.301, and 40,533 reed organs, valued at $1,718.011. The value of perforated music rolls manufactured was $833,357 ; piano parts, materials and supplies, $2,792,942 ; and all other products, $1,643,729. TALKING MACHINES The number of phonographs, graphophones and talking machines, including office-dictating instruments, manufactured during 1914, amounted to 515,154 machines, with a value of $15,290,491. The 27,221,290 records and blanks produced were valued at $11,111,418. Parts, materials and supplies were valued at $356.935 and other products at $357,072. Everyone whose memory goes back ten or fifteen years can see to some extent the effects of this development, but only figures can give an adequate idea of the wonderful growth of the industry from nothing to its present huge proportions. In 1914 there were three hundred establishments devoted to the manufacture of automobiles exclusively, producing 573,114 ears. A total of 91,997 people were employed, of which 60 were firm members or proprietors, 12,630 salaried employees, and 79,307 wage earners. The capital employed in the industry aggregated $312,876,000, and a total of $84,901,000 was disbursed in payment for services, $66,935,000 for wages, and the balance, $17,966,000, for -salaries. Materials to the value of $292,598,000 were purchased for the manufacture of automobiles. The manufacturing process added $210,632,000 to this, giving a value of automobiles made in 1914 as $503,230,000. These figures, of course, represent only a part of the automobile industry, and, indeed, so rapid is its progress that 1916 figures, if they were obtainable, would show a large increase over those given. enonnous industry, sprung, almost overnight, with the demand for more automobile members than the makers of the machine themselves could supply. In addition, in 1914, 33 establishments primarily engaged in other lines of manufacture, produced automobiles to the value of $6,636,920, and 434 establishments of this character manufactured automobile bodies and parts to the value of $10,515,070. Nine hundred and seventy-one establishments, employing a total of 53,954 people, made automobile parts and bodies in 1914. Seven hundred were firm members or proprietors, 5,469 salaried employees, and 47,785 wage earners. Capital was invested in the industry to the amount of $94,854,000, and $54,552,000 was paid out for services rendered, $19,560,000 for salaries, and $34,992,000 for wages. Materials valued at $63,610,000 were worked into products valued at $129,601,000, the process thus adding $65,991,000 to the worth of the raw material. At the 1909 census, 315 establishments engaged in the manufacture of automobiles either as a primary or as a subsidiary product ; and their output was 127,287 machines, valued at $165,099,404. During the five years, 1909-1914, there has been an increase of 350.3 per cent in the number of automobiles manufac- total value. Of the automobiles manufactured during 1914, those operated by gasoline or steam power numbered 568,- 399, and those operated by electricity, 4,715, as compared with 123,452 operated by gasoline or steam, and 3,835 by electric power, manufactured in 1909. The increase during the five years in the number of gasoline and steam machines manufactured is thus 360.4 per cent, and in the number of electrics, 22.9%. Touring cars formed the principal type manufactured during both census years. In 1914 the output of this class of machines was 454,876, valued at $351,585.518, compared with 76,189, valued at $113,510,575 in 1909. Of the total products for 1914, the number designed for pleasure or family use was 544,255, compared with 119,190 in 1909. For business purposes and for use as public cabs, omnibuses, ambulances, patrol machines were manufactured in 1914, compared with 4,262 in 1909. The output of delivery wagons and trucks was 22,753 in 1914, compared with 2,771 in 1909. The production of vehicles of less than 10 horse-power amounted to only 391 in 1914; of from 10 to 19 horse-power, to 45,116; of from 20 to 29 horse-power, to 346,399; of from 30 to 49 horse-power, to 163,468 ; and of 50 horse-power or more, to 13,025. It is interesting to note that 104,983 horse-power is developed in the automobile manufacturing plants and 68,701 in the plants making bodies and parts. The following table, listing the totals of automobile manufacturers and makers of bodies and parts, shows in a graphic way the growth of the industry. It is not, however, only in the statistics of the industry that its effects are to be shown, An auto- State of New York in 1901 and amounted to only $954. Other States gradually took up the registration of motor vehicles, chauffeurs, and operators, but for several years revenue from these sources was negligible. The total amount collected by the various States in 1905 amounted to only $62,500. The increase in sub- mobile is not like a pair of shoes, bought, used up and discarded in a year to make room for a new pair. The automobile is bought and kept for several seasons, so that only a part of the new output is absorbed by the experienced owner. The result is that the automobile wealth — or money invested in machines which yet have a tangible and tremendous value — is almost beyond computation. NUMBER OF CABS Only the registration of automobiles (in the absence of a census) can give any adequate idea of how many machines are actually in use. State registration of motor cars, including commereial vehicles, has increased 5,000 per cent, or from about 48,000 in 1906, to 2,445,664 in 1915. The first revenue derived by the State governments from automobile registration was collected in the sequent years has been almost phenomenal, and during 1915 the total gross revenues derived from the registration of motor vehicles and the licensing of operators, chauffeurs, dealers, etc., amounted to $18,245,713. Motor vehicles registered under the general designation of automobiles, motor trucks, and commercial vehicles in continental United States during 1915 amounted to 2,445,664. The road mileage of the United States outside of incorporated towns and cities is approximately 2,375,000 miles. There is, therefore, an average of slightly more than one car for each mile of rural public road. The distribution among the several States, however, is far from uniform. There is only one motor for every six miles of road in Nevada, while in New Jersey there are nearly six motor cars per mile of road. With an average of one motor car for every 44 persons in the United AUTOMOBILE ACCIDENTS That more just laws, an appreciation of the other fellow's rights and a standard of good driving, set by familiarity and public opinion, are having their effect upon "Safety First" is unquestionable. From 1909 to 1914 the number of automobiles increased more than twice as rapidly as the number of area in 1914; and the increase from 1913 to 1914, for the registration area as constituted in 1913, then containing 65 per cent of the population of the country, was from 2,488 to 2,795. Thus a five-year increase of 775 per cent in number of machines has been accompanied by an increase of 315 per cent in automobile fatalities ; and a one-year increase of 38 per cent in number of machines has been accompanied, by an increase of 12 per cent in fatalities. FOR ENGINEERING CORPS SERVICE fatalities caused by them. According to figures of the National Automobile Chamber of Commerce, the number of automobiles in use in the United States was in 1904 approximately 200,000 ; by the close of 1913 it had risen to 1,270,000 ; at the end of 1914, to 1,750,000. The number of deaths due to automobile accidents, and injuries, increased from 632 in the death-registration area in 1909 (containing 56 per cent of the population of the United States) to 2,623 in the same A more reliable comparison can be made between the increase in number of automobiles and the increase in the rate per 100,000 population for deaths caused by them. On this basis, a five-year increase of 775 per cent in number of machines has been accompanied by an increase of 258 per cent in the death rate resulting from automobile fatalities. Similarly, a one-year increase of 38% in number of automobiles has taken place along with an increase of only 10% in the death rate. most important factors in the industrial life of our nation. The change has been so sudden that its significance is not fully understood even by all those directly interested. It is not merely that we have become, almost over night, the world's greatest trading nation. For a great many years we have ranked near the top, especially in exports. It is rather that our whole attitude toward foreign markets has changed. Our attitude now is one of enthusiasm, where formerly we were Once upon a time our foreign trading consisted of selling abroad our raw agricultural and mineral products and buying in turn such manufactured products as we needed. This sort of commerce can be carried on with little effort. As a matter of fact it never required much effort on our part and it never brought us in very close contact with the problems of world trade. We did not have an international point of view. selves in a position to export their products. From the start the home market was a rich one and one with which we kept pace only with difficulty. The first foreign shipments of any consequence were largely the result of "hard times" at home, which in the past have been almost periodical with us. The shipments abroad were an effort to keep the wheels in motion while the demand at home was slack. Considerable temporary success attended this departure, although the practice of supplying customers with products one year and disappointing them the next is not one that makes for cordial trade relations. Experience in foreign trade methods was gained, however, in this way and more than one manufacturer was led to establish permanent export departments. In the latter case the American consumer, however, derived no benefit from the increased efficiency resulting from the nearer approach to maximum capacity output, and the manufacturers themselves felt no real enthusiasm for foreign trade. It was not the proper way to win the place in world trade to which we are entitled by reason of our unparalleled resources, our capacity for industrial organization, and our intelligent and industrious workmen. ican commerce may be easily traced, a table is inserted here which shows the total exports and imports for a long period of years, and also the traae of our principal commercial rivals, the United Kingdom, Germany and France. tance of raw materials in our exports is shown in the following tables, the second of which sets forth in some detail the recent development: is temporary and what part of it may be retained if we determine to retain it and determine to give our best efforts to retaining it. In a table given below it will be seen that our exports to certain of the ing the last two years we have shipped abroad a much smaller proportion of raw materials than formerly, and hence a greater proportion of manufactured goods. It is only natural that such a tendency should be viewed with the greatest satisfaction by Americans. The destination of our exports during the last two years is a matter of the greatest importance, for it indicates to a certain extent what proportion of our newly found trade belligerent European countries have increased enormously since the war started, and of course much of this increase can fairly be attributed to munitions of war and to such supplies as are needed indirectly to maintain armies in the field. This includes explosives, shells, guns, and a percentage of the clothes, shoes, and so on that are now being shipped abroad in unprecedented quantities. Fortunately for all mankind, the demand for such material cannot go on forever, and when DEVELOPMENT OF AMERICAN COMMERCE a falling off in such shipments, frithough not so suddenly perhaps as has been generally predicted. The proportion of temporary business in our European exports has been exaggerated, however. It is erroneous to suppose, for instance, that the demand for pork and wheat and corn sold to England and France at this time is a temporary one brought about by the war. We have always sold such supplies in Europe, and it is no.t likely that the per capita consumption of foodstuffs in a country at war, outside of the army, is greater than it is in times of peace. Indeed it is very probable that in a war requiring great sacrifices on the part of the general population their per capita consumption may be decreased. It is not likely that the men actually at the front consume more food than they did before the war started. Shoes and other articles of wearing apparel are of course worn out more rapidly at the front than in ordinary walks of life, although there is a strong tendency on the part of the civilians at home to make such articles "go further" than ordinarily. In considering our war time commerce with Europe and attempting to reach some conclusion as to the changes that will take place when I>eace is restored, it is well to bear in mind the fact that to counterbalance some of the inevitable losses there will be a greatly increased trade for some years with the nations that are now wholly or partly shut off from our markets. We ordinarily do a great business with the Central Powers, but after the war we shall be called upon to replenish depleted stocks in addition. This applies to Allied countries as well and perhaps to some of the neutrals. There will also be considerable reconstruction work in which the United States is well prepared, to take part. exports may be divided into three groups : ( 1 ) Exports of actual munitions of war, including cartridges, loaded projectiles, gunpowder, nitrotoluol, and other high explosives, cannon, rifles, etc. ; (2) exports of what may be called secondary army supplies, including horses and mules, automobile trucks and aeroplanes, horseshoes, barbed wire, harness and saddles, men's boots and shoes, wool clothing and blankets, and brass, copper, lead, and zinc in pigs, bars and other manufactures; (3) exports of other products that have no direct relation to the war, including breadstuff's, meat and dairy products, cotton and its manufactures, agricultural and other manufactures of iron and steel, leather, mineral and vegetable oils, tobacco, lumber and other manufactures of wood, and other agricultural, mining and factory products that we sell abroad during normal times. The total increase in the articles included in the third class, which are normally exported in times of peace, forms practically one-half of the increase in our total exports. This fact is clearly brought out in the detailed figures in tables on pages 236 and 237. Our trade with Europe, then, has recently developed to enormous proportions and there is a certainty that in some items there will be a falling off when munitions of war are no longer required ; but there is also every reason to believe that in other lines there will be 'only a gradual decrease or no decrease at all. In some lines, as lumber and agricultural implements, an increase may be expected. Our exporters and manufacturers have not failed to realize that an unprecedented opportunity for increased trade has existed for some time in countries outside of Europe, and the result is that to-day we are doing a larger business with South America, Asia, Africa and Australia than ever before. A larger share of our new business is with these countries than is generally supposed and it is a business to which too much importance can hardly be attached. If the war had ended in six months it is probable that many dealers in South America, for instance, would have returned to their old European connections, and while some may eventually return, no matter how long the war lasts, others have indicated that they are satisfied with their new American connections and will make no further changes. Some of our best lines of goods have now been on trial for some two years where previously they were practically unknown and they have established themselves permanently. The best American methods have also come to be understood where previously they were misunderstood. There are, unfortunately, a few American firms who have not realized their responsibility and have rushed in to take undue advantage of the necessities of foreign concerns. The trade done by such firms will not be retained when the war is over, but the bulk of our new business is not so done and can be retained if the proper enterprise is shown. The surplus capital that has resulted from the sudden increase in our foreign business will, or should, prove the most effective factor in making the new business permanent. Formerly it was rare to have gold flow steadily to this side of the Atlantic, but recently it has not only flowed consistently in this direction, but in quantities that were never approached before in other countries. Wisely, much of this new capital has been invested in the newer and more undeveloped countries of the world. This will insure our having a hand in building railroads, establishing industries, constructing lighting and power plants, and so forth, and this in turn will make it certain that our manufacturers will share in the business of furnishing equipment for such undertakings. This is a new departure for American capital. It is a step that has long been recognized as necessary if we are to find good foreign markets for our most important products. Coming at the time when our exports to such countries are growing so rapidly, it can be taken as an indication that a large .share of our new business is to be permanent. A table is given here to show as simply as possible how our trade to the various corners of the earth has increased recently. It will be seen at once how important a share of our exports go to regions far removed from the war zone. The growth of our trade with South America has appealed to the popular imagination more than that with any other district outside of Europe, and the assurance that a much larger business can be built up with our nearest neighbors and can be retained has not only concentrated the attention of manufacturers and exporters on South American markets and the problems connected with entering them to advantage, but has, for the first time in our history, aroused an ambition in many young men to learn the language and customs of the countries that lie to the south of us. There are hundreds of young men now preparing for .careers in foreign trade where formerly there was one, and South America more than any other section has been the lodestone. If this sudden interest does nothing more than prepare The trade with the individual South American countries in 1916 as compared with 1914, the year preceding the war, deserves careful study. This country sold Argentina $65,993,611 worth of goods in 1916, whereas in 1914 our total sales amounted to only $45,179,089. Imports from Argentina increased even more rapidly, for in 1916 we purchased $112,512,420 worth as compared with $45,123,988 worth in 1914. The imports were as usual raw materials. Exports to Bolivia showed only a slight gain — from $1,145,555 to $1,367,891— while our imports from that country amounted to $204,904 as compared to practically nothing before the war. Exports to Brazil show an increase from $29,963,914 to $41,202,277, an encouraging development that holds much promise for the future. Our purchases from Brazil increase^ from $101,329.073 in 1914 to $132,663.984 in 1916. Chile bought $17,432,392 worth of goods from the United States in 1914, but in 1916 the amount spent with us had increased to $24.289,652. We in turn greatly increased our purchases in Chile, the figures being $25,722,128 in 1914 and no less than $64,154,859 in 1916. Our exports to Colombia increased from $6,786.153 to $11,125,232 and our purchases increased from $16,051,120 to $21,458,029. Sales to Ecuador, while not so important as they ought to be, increased from $2,967,759 in 1914 to $3,462,040, and purchases rose from $3,595,456 to $5,848,290 in 1916. Paraguay is the one country with which business, both import and export, has fallen off. Our exports to that country amounted to only $173,191 in 1914, but in 1916 they had fallen off to a mere $73,452. Similarly, our imports fell from $64,651 in 1914 to $53,337 in 1916. Exports to Peru increased from $7,141,252 to $10,173,176 and imports from that country increased from $12,175,723 to $24,326,689. Our trade with Uruguay has resembled that of Peru so far as quantity goes, our exports in 1914 amounting to $5,641,266 and in 1916 to $10,274,426, whereas our imports increased from $7,715,144 to $14,475,478. Figures for Venezuela are also somewhat similar, our exports to that country increasing from $5,401,386 in 1914 to $8,999,272 in 1916, and our purchases showing a jump from $9,763,069 to $14,912,448. The foregoing figures are significant not only in showing that our exports to South American countries have increased in a satisfactory manner in the last two years, but also in calling attention to the fact that these countries are now selling a greater quantity of goods in this country. Our purchases consist of such essential raw materials as coffee, rubber, tin ore, nitrates and hides, which we need in large quantities. Before the war much of the rubber, all of the tin, and some of the hides went to Europe, there to be manufactured and shipped across the Atlantic again to the United States. Probably when the war is over the European countries will import all the raw materials they need direct from South America, but it is very unlikely that they will ever again supply us extensively with goods manufactured from South American materials. This condition not only makes for greater independence on our part, but brings us has been more rapid than the growth in our imports and is a subject that is much more interesting to most Americans. It is quite natural to dwell at greater length upon what we succeed in selling than upon what we have to buy. Nevertheless the recent great growth in our purchases abroad is significant and deserves the most careful study. In 1914 we purchased abroad $1,893,925,657 worth of goods, which is not far from normal, but in 1916 we spent no less than $2,197,883,510 for foreign products. The table that follows shows the purchases made by the United States since 1904, by continents. It will be seen that imports have fallen off from Europe only. It has been impossible for the manufacturers in the belligerent countries to concentrate on their foreign trade as they did before the war; so, in spite of the fact that we have had more money to spend than ever before, our purchases of manufactured goods from Europe have fallen off. In many quarters this fact is looked upon as a favorable one, inasmuch as it has resulted in a tendency to rely more on our own industries. Certainly our American ingenuity has had plenty of opportunity of proving itself. We are now successfully manufacturing many lines of goods that were formerly exclusively imported. From other parts of the world, however, we are making heavier purchases than ever before, but such purchases, as in the case of South American countries already mentioned, have been very largely raw materials, which formerly we imported indirectly in an unmanufactured state through European middlemen or were manufactured for us by European manufacturers. This establishment of direct relations with the newer and more undeveloped countries of the world will be most helpful, not only in saving freight charges and in doing our own work in our own factories, but in effecting closer trade relations with the producing countries. An idea of the part played by raw materials and manufactured goods in our import trade since 1870 may be had from the two tables on page 241 , the second table showing in some detail the changes that have taken place in the last two years. It will be seen that the recent trend of our import trade does not threaten American interests. We are making more and more of the manufactured goods we need, and importing more and more of the manufactured for us by other countries. For the most part the raw materials imported are such as we can not produce at home or can not produce in sufficient quantities to meet the demand. Another development of the last two years is our transition from a debtor to a creditor nation. At least it can safely be said that we are now a creditor nation so far as current accounts go. This has been the result, of course, of shipping abroad as already mentioned. Just how much has been so invested can only be estimated, but about the middle of 1916 the figure was put at nearly a billion and a half of known investments, with many other proposed loans under consideration. The largest loans have been made to the belligerent countries, but a steadily increasing amount is going into the more undeveloped countries so much more than we have been importing, which has enabled us to establish credit abroad, to buy up American securities held in European countries, and to import unprecedented quantities of gold. Much of this newly acquired capital has been used for development purposes for development purposes. The purchase of American securities held abroad has proceeded rapidly during the last two years and it is safe to say that the total amount of paper so repurchased reaches well over a billion dollars. Some estimates have put it as high as two billions. More accurate statistics are to be had on the imports of gold. The net inward gold movement aggregated $456,032,344 for the twelve months ended September 30, 1916. For the year previous the total was $205.440,751, showing that the net inward movement has doubled within a year. More gold has been added to our store in two years than has ever been added to the supply of any nation before in the same length of time, and despite all pessimistic predictions it seems only reasonable to suppose that this vast accumulation will be a powerful factor in enabling the country to hold its own in the world's commerce no matter what circumstances may arise. It will enable us to maintain ourselves in foreign markets on a much better footing than ever before and will enable us to meet without embarrassment any foreign demands for gold. Mention has already been made of the fact that we have been dealing more directly with some of the producing countries. A few special instances will be of interest in this connection. For a great many years previous to the war the world's furs were sold through London and Leipsic. Our furs, which are mostly seal, were sent all the way to London to be sold, and not until they had been auctioned off and dressed and dyed did we see them again, greatly enhanced in price as the result of two trips across the Atlantic, duties, and foreign labor. The war gave us the opportunity of organizing fur sales in this country, with the assistance of the Government, and we have learned to dress and dye our furs quite as well as anybody ever did it for us. We now buy the fur skins direct from the countries in which they are trapped, and very likely we shall continue to do so when the war is over. We are buying more rubber direct now than we ever did before, and there seems to be no reason why we should go back to European middlemen in the future. One of the most important developments in the way of direct buying has been the puivhnse of tin ore from Bolivia. We mine no tin in this country and have always been content to have England and Germany get the ore from the Straits Settlements and Bolivia and refine it for us. As a result of the difficulties encountered in getting tin in this manner under war time conditions, a company was organized in this country to buy ore direct from Bolivia and smelt it in this country. Fifteen tons of the refined metal a day are now produced here, and it is tin of the very best quality. This direct dealing with Bolivia can not help stimulating commercial relations between the two countries. In short, it may be said that this country will never in the future be wholly satisfied with indirect buying arrangements. Another interesting phase of our new position in world's trade is the increasing tendency to substitute dollar exchange for sterling exchange. Perhaps it is premature to say that the substitution is or is not going to be permanent, but it is safe to say that the experiment, even if merely tentative, has had the effect of bringing our merchants into much closer touch with the merchants of other nations than ever before. The establishment of branch banks .in South America is another important step that has been taken recently in an effort to put our dealings with our South American neighbors on a more satisfactory basis. In conclusion it might be said that the pre-eminent position which the United States has come to occupy in the last two years has then been of inestimable benefit in stimulating the industries of the country, in giving us an international point of view, and in making it possible to get into closer touch than ever before with the manufacturers, ex- Itorters, merchants, importers and bankers of other countries, and it is highly desirable that we do not let slip the advantages we have gained. It is not desirable, of course, that we go on exporting twice as much as we import, for international trade can not be conducted on any such basis for an indefinite period, but it will be greatly to our advantage to remain the first commercial nation and to retain the best of the great business so recently acquired. It can be done if American business men determine that it must be done, if they realize fully the importance of foreign trade. They can not do it if they return to the indifferent methods that prevailed when the home market was looked upon as all-sufficient. The necessity of foreign trade need not be dwelt on in an article of this kind. Even the layman has had the opportunity in the last two years of seeing what wonders a plish. The fact that our sales abroad do not comprise more than 1 to 5 per cent of our sales at home does not mean that the foreign sales are of trifling importance, as was once commonly assumed. The point is that the sales to outsiders are large enough to mean .the difference between stagnation and prosperity. They are so important that our manufacturers cannot afford to let them fall off, and it is my opinion that they will not allow any but the most temporary part of our new business to get away from them. was in the dictionary before hostilities began, but it lacked any real vitality. Americans had always assumed that they were pretty well prepared for almost any eventuality, as individuals and as a community. If we needed to fight we had a population of a hundred million to fall back on ; if we ever came to a pass where we needed more foreign trade, we could go out and get it; if we needed to make things that others had always made for us, all we had to do was make them. We were adequately prepared to do anything but drift and muddle along rather prosperously by virtue of immense resources, favorable geographical situation, and a native ingenuity and resourcefulness which we had inherited from our pioneer ancestors. What we have learned about the necessity of military preparedness will not be discussed here. This article will be concerned with preparedness for the commercial struggle which will come when peace is declared and with the preparations we are making and must make to Europe. As has been said many times, we have become the leading commercial nation of the world. This is not only true, but is becoming increasingly evident with the passing of each month. In August and September, 1916, our exports exceeded half a billion dollars, which is not only a higher figure than we ever reached before, but is much larger than any nation ever achieved before. Our imports have also grown rapidly, but the balance of trade in our favor has attained enormous proportions and our industrial prosperity is so pronounced and so real that the most carping critics no longer question it. The question is, can this great trade and this great prosperity survive the war? It is certain that we cannot retain all of the present trade and 'it is not at all certain that we can continue as prosperous as we have been throughout 1916. But it is certain, I think, that we need not suffer so serious a disturbance when peace is declared as has been pictured in some quarters. We have acquired much new business that can be retained if we make the proper efforts to retain it, and as the war goes on our opportunities for acquiring more business of that sort increase. We need a thorough appreciation of the necessity of keeping our hold on as much of our newly acquired trade as possible when the war is over. We 011 this side of the Atlantic are under the necessity of holding our own in foreign markets if we are to avoid difficulties when the war orders cease, and it is well to bear in mind that the belligerent nations will be under the necessity of winning back their old markets if they are to meet the obligations they have incurred in the war. It will be a bitter fight, with no quarter asked and no quarter given. Our competitors will not only try to oust us from our foreign markets, but undoubtedly will carry the fight right into our home markets. In planning to meet this struggle we must consider conditions that will arise immediately upon the cessation of hostilities and also the more permanent conditions resulting from the war. A number of our important industries will be disarranged when peace is made. Manufacturers of munitions and other supplies needed by the armies are well aware of this fact, but there are two classes of manufacturers who are not facing the facts. One class is manufacturing the materials that go into the munitions and the other is turning out goods that are not munitions, but which are required for military purposes. Such manufacturers should determine just how much their business has been stimulated by the war, and they should carefully charge enlargements of plant and equipment against present profits. It will be necessary also to keep in mind the fact that soon after peace is made there will be decided changes in the trade routes of the world. There will be important readjustments in the principal markets. It will be an important matter for us to have a large influence in determining these changes. The permanent effects of the war are of equal importance to us. The European nations will be compelled to seek foreign markets as they COMMERCIAL AND INDUSTRIAL PREPAREDNESS never sought them before. But let us consider carefully under what conditions they will be obliged to seek them. Will they be as formidable after the war as they were before? There has been a wide difference of opinion among economists as to how the cost of production in Europe after the war will compare with what it was before the war, but the longer the war continues the better agreed are the authorities that costs as a whole will be higher. There has been a tremendous loss of men, of labor power. Millions have been killed and other millions incapacitated. In almost all the belligerent countries there has been a rapid and steady diminution of capital. It has been used up in destruction instead of production. Taxes are certain to be excessive for years to come, for immense debts have accumulated. Fiscal affairs will be disorganized. These facts are given here to show that the increased cost of production in our country should not be considered an insurmountable handicap in the coming struggle. The point is that we are confronted with no insurmountable difficulties. There is no circumstance which which we must work out are difficult ones, however, and deserve our most careful attention, for the stability of our prosperity will "depend almost entirely upon our success in such trade. It was our foreign trade which was interrupted when the war broke out, and it was this interruption which threatened the most serious economic consequences. The war taught us that our domestic prosperity is most vitally concerned with the prosperity of our foreign trade, and it is for success in this foreign trade that we must carefully plan. Let us consider a number of important factors that will have a bearing upon our success in such trade. First of all comes the question of men properly prepared to carry on our business with and in foreign countries. We have never had an adequate supply of such men. The young American has never seriously considered preparing himself for such work. Other fields have appeared more attractive to him. Where we have had one capable man for such work the English and Germans have had dozens or perhaps hundreds. We must set about painting the advantages of the foreign field in their proper colors and we must at once concern ourselves with training men in a practical, efficient manner. We must have men who know business, who know their own particular business, who know foreign languages, who know how to sell goods, and, above all, men who can go into foreign markets with a sympathetic point of view. For the foreign field we need men who are diplomats as well as drummers. We must also pay more attention to financing foreign trade. We must familiarize ourselves not only with the extension of credits, the establishment of branch banks, the discounting of paper, but with the whole mechanism of foreign exchange and the investment of American capital in foreign countries. Of such things most of us have known very little. We must be willing and able to provide funds for the construction of public utilities,- factories, mining plants, warehouses, and other public improvements. The establishment of a conventional tariff system :s another factor that will be necessary in our campaign for foreign trade. Many nations are able, by reason of their tariff systems, not only to prohibit the sale of or to handicap the importation of commodities from economically unfriendly nations, but they are also able to encourage the exportation of their own commodities by advantageous bargains with countries which are economically friendly. A conventional tariff sys- an international point of view. It is also important that we prepare to become the market place of the world for certain staple commodities. In the past we have been content to purchase our rubber, tin, wool, furs and so on through England and Germany. It is necessary that we handle some of these supplies ourselves. We must prepare the machinery for handling them economically — the facilities for grading the articles, for buying and selling, for settling disputes, and so on. We have already made ,some satisfactory progress in this direction, and there is no good reason why we should ever go back to the old way of buying through European middlemen. One of the most important factors in our campaign will be our merchant marine. We are turning out new tonnage more rapidly now than any ether nation, and we should continue to do so. Large accessions to our merchant fleet have resulted from the Ship Registry Act. We have heard many opinions to the effect that our navigation laws are antiquated and operate to the disadvantage of American boats, yet there is no important difference between our laws and those of other important maritime countries, and there will be fewer differences as time goes on and certain European countries have an opportunity to carry out plans formulated a short time before the war started. So much for some of the important factors we must bear in mind in making our preparations. Now let us consider some of the steps already taken. ized for foreign trade. J To the Federal Trade Commission we can look for guidance in the matter of co-operating in foreign trade. This commission will also see to it that we are protected from unfair A Tariff Commission has been authorized by Congress. The benefits that will come from a scientific, non-partisan commission of this sort are too numerous to mention. In forming this commission we have taken one of the most important steps in the direction of commercial preparedness. A Shipping Board has also been brought into being. For the first time in our history we now have an efficient instrument for shaping the growth and policies of our merchant marine. Definite and constructive work in advancing our trade frontiers is being done by the Bureau of Foreign and Domestic Commerce, of the Department of Commerce. This bureau collects information about foreign markets for American goods. The sources are the consuls, the newly appointed commercial attachCs, and a corps of traveling special agents. The office at Washington is the warehouse, and the staff there and at the district offices is engaged in selling the information for action. Action is the price and results are the object of our work. The Bureau is rapidly improving in efficiency. Private corporations have been organized for financing foreign enterprises and large sums of American capital have been made available for use in countries that formerly depended entirely upon European financiers. Nothing will stabilize our newly acquired foreign trade quite so effectively as the appearance of American gold. West have organized an export sales company to assist in the sale of Douglas fir in foreign markets. This company will undertake the grading of lumber for export, the proper seasoning of such lumber, and an extensive propaganda. It is one of the most intelligent steps that any American industry has taken in this direction. It should be studied carefully by every other industry desirous of taking steps to insure itself against disaster when the war is over. There is much that remains to be done before we can look forward with complete assurance that when the war is ended we shall be able to hold the trade we have recently acquired in the world's markets. We are still in the midst of busy preparations for the future, or should be. We cannot prepare too carefully, because failure will mean a depression from which it may take years to recover. I mean preparedness to produce here at home all articles that are essential to our well being. We must make ourselves independent of the manufacturers of foreign countries. That does not mean that we must sever all relations with foreign manufacturers, but it does mean that we should be in a position to get along without them if need be — if there should be another great war between the important manufacturing countries of Europe or if we should get into such a war ourselves. ready independent. If intercourse with every other nation in the world were cut off. we could manage to get along. We could produce sufficient food for everyone and sufficient clothing and fuel. Our iron and steel industry is practically selfcontained. Building materials we have in plenty. There would be no suffering for lack of real necessities. Inconvenience and annoyance there would be though, and, if we were involved in a great war ourselves, perhaps a serious shortage of some materials essential for the manufacture of munitions. We depend upon other countries for many lines that we would sorely miss. We know it now, for we have missed gress in establishing new industries to supply goods formerly made for us by Europe and in expanding old industries to meet the war-time demand for such goods. These new industries have resulted either because certain lines of goods formerly received from the Central Powers and Belgium have been cut off altogether or because accustomed supplies from the Allies have been greatly reduced by the shortage of ships. In either case we are learning to manufacture goods that we previously purchased abroad and this experience will undoubtedly, in the long run, be of more real benefit to the country than the temporary munitions business. Our principal purchases from Germany, in the order of their value, have been hides and furs, cotton manufactures, dyes and chemicals, machinery and other manufactures of iron and steel, potash, pottery, silk and silk manufactures, toys, glac6 leather and glace'-leather gloves, rubber, paper and paper manufactures, and salt. Germany had a practical monopoly of several of these classes — such as dyes and certain chemicals, potash and toys. It seems hardly necessary to say that the cutting off of these lines was a serious matter for us. We soon realized that we must make a serious effort to manufacture our own coal-tar products and at least a certain amount of our own potash. known. Not every user of dyed goods is wholly satisfied that the quality of our dyes is yet all that it should be, but it should be borne in mind that the demand on the hurriedly built plants was enormous and that in some cases it was inevitable that quantity rather than quality should be given first consideration. Improvement in quality has taken place steadily, however, and it is not likely that much more fault will be found in that direction. We are now producing about half the ordinary requirement of some 29,000 tons annually and the difference has been partly made up by the use of natural dyes. Congress has accorded protection to the new industry in the shape of additional tariff and the Bureau of Foreign and Domestic Commerce has supplied a detailed census of the dyes we imported in normal times. This census is aimed to assist manufacturers in determining how much of each color is actually needed by the dye users of the country. Previous to the publication of this work only our dyestuff importers had any such knowledge of the market. One Buffalo manufacturer has stated that the census has saved him a million dollars and years of wasted effort. There are a number of other coaltar products for which we formerly depended upon foreign manufacturers, including carbolic acid, aspirin, acetanilid, photographic developers, salicylic acid, saccharin, creosote and benzoic acid. These are all manufactured at home now, although not in the quantity that might be wished. Prices are very high. But we have demonstrated our ability to manufacture them and it is not likely that we shall allow the experience to go for naught. The lack of potash has been a sore point. The German deposits caa be worked so cheaply that in the past there has been no incentive to recover the material from kelp, alunite or other sources, but when the German supply was cut off there began an eager searching of our own resources. The result has been that we have made considerable progress in recovering potash from kelp, alunite, the brine of certain alkaline lakes, tobacco stems, mica and in the manufacture of Portland cement. The supply has been barely sufficient for industrial use, however, and our fields have had to do without it. supplied now than ever. Good progress has also been made in imitating typical German products, and it is not at all likely that Santa Glaus will ever again import heavily from abroad to fill our stockings. As a matter of fact we are doing some foreign business in this line ourselves and satisfactory relations have already been established with dealers in England, Australia and South America. almost entirely upon England and Germany for our refined tin. These countries bought their supplies of ore and partly refined tin from the Straits Settlements and Bolivia and did the work the supply in this manner and a firm was organized to import the ore from Bolivia and smelt it in this country. The new plant is now turning out fifteen tons of the finest tin a day. We need about 45,000 tons a year. An attempt is being made to establish an all-American linen industry. For years before the war started the United States was the greatest consumer of linen goods in the world and practically all such goods were purchased abroad. The war has greatly interfered with these imports, for Russia is by far the greatest producer of the raw flax fiber required by the Irish, Belgian and French mills. In this country flax has been raised almost entirely for the seed, which is used to manufacture linseed oil, and the Department of Agriculture has estimated that in 1915 there were some 3,000,000 acres devoted to this crop. Of this great total only 2,000 acres were planted in flax for fiber, the yield for this purpose being estimated at only 4,000,000 pounds. It should be kept in mind that flax growing for seed aud flax growing for fiber are two separate and distinct industries. To some extent flax is grown for both seed and fiber, but the farmer must decide which is to be the main product and which the by-product, just as the sheep raiser must decide whether wool or mutton is to be the main consideration when he selects the stock he is to raise. In Russia the flax grower not only raises the flax but prepares the fiber for the mills, and this is a disagreeable and insanitary process and one that depends upon very cheap labor. The problem in this country was to find a satisfactory chemical process of preparing the fiber that could be carried on in a factory. Such a process has apparently been worked out, for several important concerns are now buying flax on a large scale in the West. They are also assisting the farmers in a financial way. The manufacture of the coarser goods from this straw is now being carried on successfully and in time the high-grade linens will be made also, in spite of the reputation of foreign makes. In the past our dollars annually. The manufacture of certain lines of Cotton goods has expanded in a surprising manner since the war started. There has been a marked increase in the production of fine count and novelty fabrics and manufacturers have demonstrated their ability in designing and finishing such goods. Embroidery cotton, both mercerized and plain finished, heretofore produced almost exclusively abroad, is being made satisfactorily by domestic spinners. There has also been an increase in the manufacture of brass bobbin yarn for lace manufacturers. The large demand for all fine counts, combed, gassed and mercerized yarns has forced a considerable increase in production. Scrubbing, wiping and allied cloths produced with yarns spun from cotton waste, and hereto- The shutting off of the supply of full-fashioned hosiery formerly imported from the Chemnitz district in Germany has greatly stimulated the production of such hosiery in this country, as well as some grades of fine-gaged seamless hosiery. The shortage of dyes has been the only obstacle in the way of completely meeting the demand for the best grades of hosiery. The only large artificial-silk plant in this country has doubled its capacity since the war started and it is said that sevei-al other such plants are to be started. Several firms that previous to the war imported loopers ami flat bar knitting machines have started the manufacture of these articles. Before the war this country depended almost as a matter of course upon German and Austrian sources for sugar-beet seed with which to keep going our flourishing young beet-sugar industry. Ordinarily the consumption of such seed in this country is about 135,000 bags, or approximately 15,000,000 pounds, and this is almost exactly the amount of seed we imported in 1913. It is estimated that the production of seed in 1916 was 60,000 bags and that in 1917 we shall have a yield of 85,000 bags. The present producers assert that they are going right ahead until it is no longer necessary to depend upon outside sources. An American industry with a million dollar market has come into existence as a result of cutting off the imports of petroleum from Russia. By the end of 1914 at least a score of American refiners were experimenting in the new field and at least ten sources of domestic white oil for medicinal purposes were developed. These new American products are quite the equal of the Russian product and will probably hold the market permanently. The war found us unprepared to manufacture enough lanolin, or refined wool grease, to meet the demand. Ordinarily we import about 12,000,000 pounds of crude wool grease and 2,500,000 pounds of .lanolin. The domestic production of crude grease is about 6.000,000 pounds, but very little lanolin has ever been made at home. We have always used the crude grease in tanneries, cordage factories, etc., and left to others the work of preparing the refined wool fat, so valuable in salves, ointments and emulsions. Now we are at work doing our own refining. dressing and dyeing 10,000 sealskins by a process formerly used only in England. The plant is being expanded. In the past we sent the skins to London for dressing and dyeing, in spite of the fact that we are the largest producers of sealskins in the world and the largest consumer. The first sale of fully dressed and dyed sealskins wholly "made in America" ever held in this country took place in October. 1916. We shall never go back to the old way of carrying on this business. Within the last two years there has been introduced into this country the chemical porcelain industry, with the help of the Bureau of facturer who believed chemical porcelain could be made from American materials in American factories. Now two establishments are making the best type of modern chemical porcelain. In the past much of the clay used in this country in the manufacture of porcelain came from England, that for the manufacture of crucibles and other high refractories from Germany, and that required for other fine products from France. Experts in the Department of Commerce have pointed out that clays for all these purposes may be obtained in the United States and by proper treatment be made equal and in many cases superior to the material heretofore supplied by Europe. Many of these clays are found in the South and are now being used commercially. Before the war all naphtha and gasoline safety lamps were purChased in Europe. Since the war started some of the foreign patents have expired and several American lamps of this type have been placed on the market. With the help of the Bureau of Mines there have also been developed several types of permissible electric safety lamps, which are now in the market in competition with foreign makes. lating effect on the production of crude and calcined magnesite in California. In times past these deposits have been used very sparingly, and principally in connection with the paper industry. In 1913 the imports amounted to approximately 168,000 tons, while the domestic production did not reach 10,000 tons. The imported material was largely used in the manufacture of refractory furnace lining and in the manufacture of paper from wood pulp. No exact data as to the present output of the American companies are available, but it is thought that the domestic production in 1916 was about equal to the former imports. Eastern users, however, are. urging greater production. There has been a striking increase in the production of cutlery and related articles. The old American preference for imported articles h;is kept alive in this country a thriving business in such articles. Barber shears, razors^ butcher knives, cleavers, boning knives, and so on, are now supplied by American manufacturers in sufficient quantities to meet the demand. All these articles needed was a fair trial. As a result of restriction placed upon the shipments of asbestos from Canada, which is the world's chief source of supply, we are now paying attention to our own deposits. In 1915 there was a great increase in the production of high-grade asbestos in Arizona. The lower-grade asbestos produced in this country comes mainly from Georgia. Deposits are now reported from the Caspar Mountain and other regions in Wyoming. The Geological Survey is of the opinion that the present output can be greatly increased. The list could be greatly extended, but the foregoing should be sufficient to prove the point that when Americans are forced by necessity they can manufacture practically any line of goods. We have it in us to make ourselves industrially independent of all other nations in case of necessity, and we are rapidly making progress in that direction. From the evidence in the case, therefore, it appears that it is possible to make preparations that will save us from disaster in foreign trade when our old competitors reenter the field. We haven't made all the necessary preparations at this writing, but we are doing well and there is a great deal of vitality in the movement now where at first there was only talk. And we are proving that we never again will have to depend upon others for important products. "Preparedness" has a real and vital meaning for Americans to-day. THERE are nearly 22,500,000 enrolled in educational institutions in the United States. Of these, 19,500,000 are in elementary schools; 1,450,000 in secondary schools, both public and private, and 216,000 in colleges and universities. Close to a hundred thousand are in normal schools preparing to be teachers; 67,000 are in law, medical and other professional schools, and the remaining million or more are in various types of educational institutions. There are 706,000 teachers, of whom 580,000 are in public schools. Annual expenditures for education aggregate $800,000,000. has developed as a State rather than a national matter. All the States provide elementary education, ranging from seven to nine years, and secondary education of one or more years, and in practically every State higher educational opportunities are available without cost for tuition to both sexes. Recently provision has been made in some States for adequate vocational, commercial and professional education at public expense, but only a small number of States have as yet created State systems of vocational education. Support of schools is from State and local sources, the proportion ranging from Massachusetts, where 96.8 per cent of the funds come from local taxation, to Alabama, where only 24 per cent of the funds for school purposes come from local taxation and 69.4 per cent from the State. The Federal Government early in its history made important grants of land for general educational purposes; it gives financial aid to agricultural and mechanical colleges and experiment stations in all States, and has recently begun to support extension education for agriculture and home making. It has also maintained, since 1867, a Federal Bureau of Education which serves as a clearing house of information on educatior for the benefit of all the States Control of public schools, originally centered in the local community, has lately become transferred in large measure to the county and to the State, as State aid and responsibility for education have broadened. Conditions still vary, however, from almost complete State domination in a few States to nearly complete local autonomy in others. The National Government exerts no control over education in the States other than that involved in the administration of certain land grant funds and appropriations for extension education. The function of the Federal Education is compulsory, to a greater or less degree, in all the States except one — Mississippi. Massachusetts adopted a compulsory education law in 1852. Vermont followed in 1867; Michigan, New Hampshire and Washington in 1871; Connecticut and New Mexico In 1872 ; Nevada in 1873 ; California, Kansas, New York, New Jersey, the Southern States: Alabama, Florida, South Carolina and Texas in 1915 and Georgia in 1916. The laws vary widely in scope and effectiveness. In some States they are operative only after acceptance by counties and local communities; in others they are effective for only part of the territory of the State, large areas being exempted. The upper age limit for compulsory attendance ranges from age 12 in Georgia, Kentucky, North Carolina and Virginia, to age 16 in sixteen of the States, and 18, under certain conditions, in one (Idaho). The more usual compulsory period is 8 to 14 years of age, or "until completion of the eighth grade." The minimum attendance in any one year varies from twelve weeks in Nebraska and Virginia to the "full school year" in twenty-nine States. Compulsory education laws have IV. ILLITEBACY Illiteracy in the United States is 7.7 per cent as compared with 1 per cent in Great Britain, 4.3 per cent in France and 0.05 per cent in Germany. According to the census of 1910 there were five and a half million illiterates in the United States over 10 years of age. This is over a million more than the combined total population of Mon- Massachusetts and Rhode Island (5,438,945) ; or of South Carolina, Georgia and Florida (4,877,140). A State made up of these illiterates would be nearly as large as Illinois (5,638,591). There were more illiterates in 1910 than comprised the entire population of the United States in 1800 (5,403,383), or the equivalent of the entire combined metropolitan population bf Philadelphia, St Louis, Boston, Cleveland, Baltimore, Pittsburgh, Detroit, and Buffalo. The percentage of illiteracy in the United States was lowered between 1890 and 1910 from 13.3 per cent in 1890 to 10.7 per cent in 1900, and 7.7 per cent in 1910 ; but the number of illiterates decreased less than 15 per cent and the number of foreign born illiterates increased 43 per cent. More than two-thirds of all illiterates are country-dwellers ; the rural illiteracy (10.1 per cent) is nearly twice that in the cities (5.1 per cent). Existing illiteracy is therefore ascribed to foreign immigration and lack of school facilities in country districts. The State and national governments are aiding city evening schools to eliminate illiteracy among the foreign born, and several States — Kentucky, Alabama, North Carolina — have created State illiteracy commissions to deal with the problem in rural communities. V. TYPES OF SCHOOLS Elementary. — Elementary education in the United States has become almost exclusively a public function. Of the 1,626,310 pupils reported in private elementary schools, 1,429,859 are in parish schools of the Catholic Church. Private kindergartens and special schools account for a large part of the remaining number. Secondary. — The high school is the most typical American educational institution. There are 11,674 public high schools, of which 8,440 education has become more and more a public function; 89 per cent of the secondary students are in public high schools. It is estimated by the United States Bureau of Education that 25 out of every 100 children who enter school reach the high school, and that 10 out of every 100 graduate from high school. The most important recent change in secondary education is the gradual introduction of the so-called "six-and- and 468 under private control; 327 are controlled by religious denominations ; 140 are for men only ; 83 for women only ; and 340 are coeducational. There are 152,307 men students and 84,861 women students.* The number of men students has of this chapter. six" plan of organization, whereby six years are assigned to elementary education and six to secondary, the latter period being divided into "junior" and "senior" high schools of three years each. A hundred and fifty cities had taken steps toward adopting this form of organization in 1915. colleges and universities listed by the United States Bureau of Education, 95 are public institutions VI. TEACHERS Of the 706,152 teachers employed in the United States, 169,029 are men and 537,123 women. The number of teachers nearly doubled in the thirty years between 1885 and 1915. Nearly five-sixths of the teachers in public elementary schools are women, and of the 57,909 public high school teachers, 32,862 are women. The colleges and universities have 5,293 women instructors and- 19,447 men, The following table summar- VII. VOCATIONAL EDUCATION Six States — Massachusetts, New Jersey, New York, Pennsylvania, Indiana and Wisconsin — have regularly established systems of vocational or industrial education. Two others been pointed out that prior to the outbreak of the European war more trade workers were being trained at public expense in the city of Munich than in all the larger cities of the United States combined. maintain State-aided vocational schools, and some form of vocational or industrial education is provided by eight other States, while in the States which do not provide State aid for vocational education separate municipalities have established several types of vocational education at public expense. The need for industrial training for the youth of the nation has been urged by organizations of business men, labor-union workers, and schoolmen within the past few years as a measure of national conservation and preparedness. European nations — especially Germany — have been ahead of the United States in this regard. It has in the United States for 1914, the latest year for which statistics are available, was $794,459,968. The table over leaf shows the distribution of this expenditure and the per capita Cost for different types of schools. In the forty-four years, 1871 to 1914, private philanthropy added $584,418,082 to the available funds of colleges and other educational institutions in the United States. The bulk of these funds goes to colleges and universities. Of the $31,357,398 given in 1914, $26.670,017 was for universities and colleges, $1,558,281 for schools of theology, $203,067 for law schools, $1,495,773 for medical schools, $607,431 for public normal schools, $116,283 for private normal schools, and $706.546 for private secondary schools. The following table shows the annual amount of gifts and bequests to education since 1894 : X. LIBRARIES There were over 18,000 regularly established libraries in the United States in 1913, containing more than 75,000,000 volumes. The number of EDUCATION Of the 2,849 libraries containing 5,000 volumes or over, 1,844 are classified as "public and society libraries," and 1,005 are school and college libraries. Public and society libraries have an aggregate of over fifty million volumes, with seven million borrowers' cards in force; 1,446 of these libraries were entirely free to the public. Libraries reporting from 1,000 to 5,000 volumes numbered 5,453, of which 2,188 were public and society libraries, and 3,265 school libraries. These libraries contained 11,689,942 volumes. Another group of libraries, comprising those that reported from 300 to 1,000 volumes, increased the total by 2,961,007 volumes. reported for the entire United States, more than half were in the North Atlantic States, and they contained 24,627,921 volumes out of the total of fifty millions; and of the three million volumes added to library collections for the year 1913, almost one-half were for the same section. New York State had 7,842,621 volumes in her 213 libraries ; Massachusetts, 7,380,024 in 288 libraries; Pennsylvania, 3,728,070; and Illinois, 3,168,765 volumes. Four-fifths of the borrowers' cards in use were in the North Atlantic and North Central States. THE NAVAL PROGRAMME OF 1916. ON August 29, 1916, President Wilson signed the Naval Appropriation Bill, authorizing a three-year building programme, of greater size and importance than this nation has ever previously contemplated. To get a perspective on this bill and what it means, consider that, at the time, it was hailed as the greatest step forward America had ever taken in Naval matters, and then compare with the present unheard of activities and expenditures, which are fitting the American first line of defense to play a part in the world war commensurate with the necessity and American traditions. The Navy Department has had to reverse its peace time policy of giving information, almost completely. In normal times it is sufficiently easy to gain statistics of the Navy — in war time almost impossible. Thus, according to the official reports there were upon the Navy list 399 vessels June 30, 191.% listed as follows : Battleships, 41 ; submarines, 57 ; fuel ships, 24 ; tugs, 48 ; yachts, 16 ; cruisers, 24 ; gunboats, 31 ; destroyers, 69 ; torpedo boats, 20 ; transports, 6 ; tenders, 9 ; monitors, 9 ; special types, 8 ; supply ships, 5 ; hospital ships, 2 ; armored cruisers, 10, and ships of all kinds in an unserviceable condition, 20. In addition to this list of ships there are authorized by the Naval Act of March 3, 1915, battleships Nos. 43 and 44, destroyers Nos. 69 to 84, inclusive, and submarines Nos. 60 to 77, inclusive. Appropriations for the beginning of the construction of these vessels were made available July 1, 1915. These figures are requoted from the former edition of this book to give an adequate idea of what the United States Navy is when on a peace basis, and to afford a comparison to the statement that the Navy has now in service nearly April 6, 1917. The war-construction program of the United States Navy now comprises 787 vessels, including all types from super-dreadnoughts to submarine-chasers. Some of these have been completed in the past few weeks and are now in service. The rest .of the program is being pushed to completion. The total cost »is estimated at $1,150,400,000. The second had an item of $100,000,000 for Naval emergency. The Navy has authorizations for $86,145,000 in contracts to be paid by future Congresses. The Yards and Docks program calls for a hundred millions. New construction is being entered into as fast as the ways can be provided, and the results are amazing. For instance, $350,000,000 is being spent on new destroyers. Of this program. Secretary of the Navy Daniels has said : "These destroyers will be built by five companies which have had experience in .building this type — the Fore River Shipbuilding Corporation, Boston; the New York Shipbuilding Corporation, Camden, N. J. ; Cramps' Shipyard, Philadelphia ; the Newport News Shipbuilding and Drydock Co., Newport News, Va., and the Union Iron Works, San months ago it looked as if it could not be done. Orders had already been given for all the destroyers the yards could build, and almost as many as the new program calls for are now under construction or contract. To build rapidly the additional destroyers requires a great extension of shipbuilding facilities and the erection of new plants for building engines. The companies were unwilling to invest millions in these additions so the Government must build and will own the new plants and extensions which will be used by the builders. "We are putting every energy and facility behind this project. Some of the new destroyers are promised for delivery in nine months, all within eighteen months. These vessels will be of the latest and largest improved type, which has just been tried in our service and found to be unsurpassed by any destroyers in the world. The plans are all ready and the adoption of a uniform type will enable us to reduce the number of types." United States Navy might have been, under peace program activities, is included here. Very obviously, no one can say what the 1922 Navy will be, since we know neither what will be then built nor what, by then, destroyed by the enemy. The quotation is from the original edition of this work, — NAVY OF THE FUTURE In its 1915 departmental report the Navy Department lists those ships of the present fleet, afloat and building, which will be serviceable in 1922. To this list must now be added the authorized ships in the most recent Navy bill, in order to gain an idea of what our present and projected Navy will amount to when the present stupendous program is completed. Of course, the program prior to 1922, and unquestionably further additions will be made to the Navy in future Congresses, but the following list, which is compiled from the Navy Department figures plus those of the new bill, should indicate the ap- proximate strength of the Navy in usable, fightable ships at a date of approximately 1920 to 1922, as far as present knowledge can project it : COST OF NAVY The total cost of all the ships upon the Navy list to the date mentioned, and excluding the new work authorized in the Naval Act of It must not, however, be supposed that adding together the cost of battleships and the cost of naval establishments gives any idea of the cost of the entire Navy since it was first began. The total expenditures for the Navy from 1794 to 1915, inclusive, totals the unthinkable sum of $3,214,339,051.10. This, of course, includes ships, establishments, pay, materials and all expenses in connection with the Navy Department. which must be made during the continuance of the war the remarkable fact is evident that within the space of from one to three years, the United States will spend upon its naval establishment, a sum eqiial to that which has been spent upon it since the modern Navy idea first came into existence ! counts of the United States Navy requires a closely printed statistical report of 294 pages to summarize the financial operations of the Navy. Nothing, therefore, but the most comprehensive and inclusive statistics can be given in the short space here available. The table on the next page will be found interesting as showing the principal items of expenditures in connection with the Navy on a peace basis. NAVY YABDS, STATIONS, POSSESSIONS To'the average man the »Navy consists of the vessels which float in the water and such property as may be upon them. To the naval man, however, the property ashore necessary to maintain the ships at sea is every whit as important as the vessels themselves, and, as will be seen in a moment, is no inconspicuous part of the expenditures necessary to make or maintain the Navy. The United States possesses eleven navy yards in the United States, located at Portsmouth, Boston, New York, Philadelphia, Washington, Norfolk, Mare Island, Puget Sound, Charleston, Pensacola and New Orleans. Across the water it has navy yards in Hawaii, Cavite and Olongapo. It possseses naval stations at Port Royal and Key West, and coaling stations at Frenchman's Bay and Melville, and in addition has property at Sitka, Alaska ; New London, Conn. ; Yokohama, Japan ; the Naval Academy at Annapolis, the naval proving ground at Indian Head, a naval hospital at Las Animas, a naval base at Culebra and a torpedo station at Newport, R. I. The investment in these naval establishments totals $196,059,926 since the beginning of the modern idea of the Navy in 1800, when the Ports- mouth, Boston, Washington and of the shore establishment. For Norfolk navy yards were first estab- instance, naval training stations lished. have mushroomed almost overnight, How these shore establishments to take care of the immense inare increasing in size and scope crease in personnel required by the under the stimulus of war and war. Ten thousand men are being almost unlimited money is difficult trained at the new naval training to grasp, even were inclusive figures camp at Hampton Roads, which inavailable. Obviously the Navy De- eludes four hundred acres and one partment is not publishing all the hundred ana fifty buildings. And it details of its increase of yard and is only one of many, on which a docking facilities. But certain tremendous job of rush work has things are known of the activities been done so quietly that little ap- preciation of it lias been manifest in public, particularly when the army cantonment construction work has somewhat overshadowed it in magnitude. Yet the Navy training camp and cantonment work has sented an investment of over $2,000,000. On July 15 the camp site on the grounds of the Jamestown Exposition of 1907 was largely covered with brambles and scrub pine. Four thousand laborers were set to work and in a few weeks roads had been cleared, marshes drained, and 90 buildings, including barracks and mess halls, erected. The site was scraped, levelled and drained, 150 large frame buildings erected ; sewerage, lighting and waterworks provided and details rapidly completed. Three former exposition buildings of brick and concrete construction are used for permanent administration and school The Great Lakes Naval Training Station near Chicago, is also practically completed. More than 12,000 men are in training at Great Lakes. The full quota will be 17,000. Great Lakes, the largest naval cantonment, consists of six camps built around the central permanent establishment on the Lake Michigan shore — Camps Dewey, Perry, Decatur, Paul Jones,- Farragut and Ross. Work on these was started June 15th, and in four months the facilities of a modern city have been provided at an outlay of a million dollars a month. Large vide for dTills during the winter. Fifteen other camps for Naval recruits already are complete. The one at Pelham, N. Y., at the head of Long Island Sound, accommo- Navy Yard for 5,000 men was finished August 30 after a hundred days of work. Quarters for 5,000 •were erected at Newport in 30 days, having been completed several months ago. At Mare Island, California, site-clearing began May 8 and barracks for 5,000 men were ready July 14. The Puget Sound In Brooklyn, a camp for 3,000 was erected in a city park between July 1 and August 1 ; at Charleston, S. C., quarters for 1,000 were built in twenty days, and 4,000 others in five weeks. Work is proceeding on the new camps at Gulfport, Mississippi and San Diego, California, extensive exposition grounds at both places having been taken over by the Navy Department and converted into ENLISTED PERSONNEL Having a certain number of fighting ships and the required naval stations, bases and navy yards to keep them in condition, a navy would nevertheless be helpless were it not for its personnel, regarded by Navy men as equally important with material and equipment, and generally all too much disregarded by the apporpriating power, unfortunately a non-technical body of men. The total enlisted force in the United States Navy was, on June 30, 1915, 52,561 men, of which 47,505 were native born and 5,056 were foreign born. Of these, 48,908 were white, the balance being negro, Chinese, Japanese, Filipino, Samoan, Hawaiian, American Indian and the enlisted force. New York furnishes the largest number of native born American seamen in the American Navy, 6,719, and Alaska the smallest number with 6. Contrary to the general opinion the United States Navy does not have difficulty in obtaining men for enlistment. Its troiible comes in the high standard which makes the majority of applications result in rejections. For instance, during the year 1915 there were 102,561 applications for enlistment. Of these only 17,704 were enlisted and 6,291 of this number were re-enlistments. Over 61,000 of the rejections were on account of disability and 17,000 for other causes. times as many shirs need three times as many men, but in addition a surplus of trained men must be available in case of naval disasters, to take the places of those who may fall in battle. So it is not surprising to learn that, in the training stations and already trained, the Navy has a total force of more than a quarter of a million men, inclusive of the Marine Corps. On April 6 there were 64,680 enlisted men in the regular navy ; now there are 143.726, an increase of 79,046. The Naval Reserve Force has increased from about 10,000 to 49,000; 14,500 naval militia are in the Federal service ; the Coast Guard, with its force of 5,000, has been transferred to the Navy for the duration of the war ; the Hospital Corps has been increased from 2,000 to 6,500. The Marine Corps has increased from 13,266 enlisted men on April 6 to an enlisted strength, with reserves, of 32,348. There are about 12,000 officers in the Navy and 1,122 in the Marine Corps. It hardly needs pointing out that, merely because we are at war, we cannot station every naval man at a gun and bid him shoot at a Ger- man. It is as essential to keep the establishment in working order now as in peace times, and to that end a certain proportion of our naval forces must be distributed in peaceful occupations. No figures are available now as to just where our forces are, but the table for a recent peace year will show their approximate peace distribution. While many will have been called in for more strenuous duty, by no means a small proportion of men engaged as shown will remain in these same stations throughout the war. SCHOOLS In order to supply men qualified for certain ratings in the Navy, the following schools are maintained : Mess attendant school at Norfolk. During the last fiscal year 2,278 men were pursuing courser, at these various schools. Of these, '1,302 completed their course and were detailed 'to active duty. A new class of enlisted men at the Pensacola Aviation School is formed every three months. Some of these men are taught and exorcised in the principles of flight, and all are trained in the mechanics of aviation. Recently a school for the care and handling of gasoline engines was added to the School for Machinists' Mates at Charleston. It Schools at New York and Mare Island have been extended to include, besides the Continental Morse Code, the American Morse Code, so that all the men who qualify at these schools may be competent to talk to any commercial shore stations as well as the naval stations. The need for these schools has quadrupled with the war, and their activities are being- rapidly extended. Not only has the Navy entered a building program such as the United States has never seen, but has taken over hundreds of vessels for special purposes, all of which must be manned. The Atlantic Fleet comprises twice as many vessels as in peace times. Every battleship and cruiser that was in reserve has been fully manned and commissioned. Every warship is now a training school for the instruction of men in gunnery and engineering, and notable results have been achieved, especially in target practice with guns of the smaller calibres used in fighting submarines. DESERTIONS One of the troubles of all navies is found in the practice of desertion. Many men cannot stand discipline, others become dissatisfied for one reason or another, and, failing to understand the seriousness of the offense or being willing to take the chance of punishment if detected, absent themselves from the Navy without permission and thus become deserters. Two thousand three hun- dred and twenty men thus deserted during 1915, a decrease of several hundred under 19-14 and a still larger decrease from 1913 and 1912, the figures for which are respectively 3,237 and 3,055. Of the 1915 deserters, 480 voluntarily returned to service, and 413 absentees were apprehended and delivered. In 1907 a finger print identification system was installed in the identification office which now contains the finger prints of 133,214 men, including, of course, all those who have enlisted in the Navy since the establishment of this system. The result of the finger print system is to prevent re-enlistment under assumed names of men who have deserted from the Army and Navy or Marine Corps or who have been discharged for various reasons which would prevent them from reentering the service under their own names. The finger print identification system has a new ramification in the providing of every enlisted man and every officer with a finger print identification tag in metal. This tag is made of a material which will not melt even at a very high temperature and which is not affected by sea water. It is etched in acid after the inked finger print of the right forefinger has been rolled upon it, and bears on the reverse the name and rank of the officer or name and enlistment date of the man who wears it. This always supposing that in any accident in which he may be killed or injured, his hand is not destroyed. This system, had it been then in use, would have served to identify the unknown dead of the ill fated Maine. PEACE SEBVICES Of the functions of the Navy in time of peace much could be written, but space forbids. 'Perhaps nothing sums its labors up better without wonderment. When the truth is finally known, as to the numbers of troops transported and the numbers of ships which have been taken through the submarine hunting grounds without accident, not only this country but the whole world will marvel at the efficiency of the Navy. Close followers of the news in the daily papers, inaccurate though it often is, will have noted the undoubted facts that submarine activities are on the wane. Inasmuch as there is nothing a submarine fears so much as it does a destroyer, and the aeroplane, and inasmuch as we have both very much on duty with parts of the allied fleets, the inference should be a point of pride to every American. In this connection it should be said that the Navy has not been backward in aviation. A new aeroplane station at Cape May was authorized by the last Congress, and a million dollar factory is being finished in Philadelphia. But, as in the case ol the Army, nothing is being said as to numbers of machines, aviators or types. The prevention of submarine activities, and the safety of merchant vessels by convoy, or otherwise, is of course a naval problem, even if one in which many civilian activities are engaged looking for a greater success. The Naval Consulting Board, the Ship Protecting Committee, the National Research Council, and a large number of private concerns, either commandeered by or volunteered to the Government, are working on many ideas for the elimination of the submarine menace. Of those which are scientific and instrumental — such as for instance, devices for de- tection of submarines through sound or otherwise — it would not be patriotic here to speak. But the most obvious remedy — the building of ships faster than the submarine can sink them — while not strictly a naval activity is so intimately related to the Navy as to need mention here. fense of the home coast line, and perhaps a co-operation with the allied navies in blockade, the greatest function of the United States fleet in the Atlantic will be convoy work. And it seems as if the Navy would have plenty to do in that respect and very shortly. with an aggregate tonnage of 2,871,359, either engaged in or capable of participating in foreign trade. The United States Shipping Board Emergency Fleet Corporation has commandeered 403 steel ships of more than 2,800,000 tons which are being completed or under contract for construction in American yards. Figures show that the United States will have near the end of 1918 a merchant fleet of more than 1,600 ships aggregating 9,200,000 tons to carry its foreign commerce, as compared with an of 1,039 ships. Of these, 353 with a total deadweight tonnage of 1,253.900. are wooden ships; 58, with a total deadweight tonnage of 207,000 are composite; 225 with a total dead- THE NEW NAVY Urgent Deficiencies Appropriation a provision and authorization for the construction of further vessels whose total deadweight capacity will be approximately 5,000,000 tons. 11,000,000 deadweight capacity. The total authorization for this work is. approximately $1,799,000,000 for the Shipping Board and the Emergency Fleet Corporation. Of this amount the appropriation is $1,085,000,000, including the amount carried in the recent Act. The authorization will carry the Emergency Fleet Corporation's building program well into the year 1919, but a very large part of the 1,039 vessels now under construction will bo completed during the calendar year 1918. In addition to the tonnage being constructed by the Emergency Fleet Corporation, there have been taken over 103 German interned vessels with a total tonnage of 611,799 deadweight tons. All of these except 20, with a tonnage of 120,500 tons have been repaired and are now in the service of the Army or Navy, or the Allied Government. The remaining 20 are still in process of repair and will be similarly employed when the work upon them is completed. In addition, 14 Austrian interned ships have been acquired for the use of the United States and our Allies. Their tonnage aggregates 88,505 tons. submarine campaign or depends upon sea raiders upon the surface, it is obvious that she will make every effort to nullify this tretremendous building program. A United States Army in France is of no military value without constant accretions of men, a steady flow of munitions, a constant supply of food. Neither men, munitions nor provisions can be, had in Europe — everything General Pershing needs must come from America. It can only come in ships. The Nothing that the Navy has done or can do will tax its personnel, its ships, its efficiency, its patriotism to a greater degree than this, and if, as every American firmly believes, it measures up to its responsibilities and its opportunity, the inglorious duty of acting as policeman of the seas, and convoying merchant vessels instead of fighting brilliant battles, may have a greater effect in winning the war than any naval engagement of the past has had in settling international difficulties. United States Army which will not be out of date before it is printed, because the progress of the Nation towards an efficient war footing is so surprisingly rapid. Without the perspective of time, it is difficult to estimate the economic effect of the selective draft law. Before its operation, our Army was 175,000 men. Today we have a million men under arms or in training, and have secured them by a process of law, an elimination of the unfit and the most gigantic lottery ever held, with hardly a ripple upon the surface of the body politic. The General Officers, General Staff Corps, Adjutant General's Department, Inspector General's Department, Judge Advocate General's Department, Quartermaster Corps. Medical Department. Medical Reserve Corps. Dental Corps, Contract Surgeons. Corps of Engineers, Ordnance Department. Signal Corps, Bureau of Insular Affairs, Chaplains and Military Academy. Commands in the field are organi/ed as Cavalry. Field Artillery, Coast Artillery, Infantry and Philippine Scouts. On September 20, 1916, there, were authorized 11 Major Generals and 30 Brigadier Generals, 244 Colonels, 231 Lieutenant Colonels, 658 Majors, 2,099 Captains, 2,562 First Lieutenants, 1,369 Second Lieutenants and 85 Chaplains as officers, a total of 7:289 for a total authorized strength of 117,038 enlisted men. Creating a national army by selective draft is a sufficient problem, but nothing to that oi finding officers for it after it is created. A capable officer can train men to be soldiers in a few months. But to train men to be officers in a few months seemed an impossible task. Nevertheless, to some extent the problem has been solved, and is still in process of solution. Prior to the war the Officers Reserve Corps was created by act of Congress to secure a Reserve of officers available for service in the Army, as officers of the Quartermaster Corps and other staff corps and departments, as officers for recruit rendezvous and depots, and as officers of volunteers. Members of the. Officers' Reserve Corps are not subject to call for service in time of peace. The President is authorized to appoint and commission as Reserve officers in all grades up to and including that of major, such citizens as are found qualified to hold such commissions. fore the war came to America. Some had prior military training, others were officers in the National Guard and still others, by virtue of their special knowledge and civilian accomplishments had services to offer the Government which were of value sufficient to win them Reserve commissions. enough to officer the new army. Hence one of the first steps of the Adjutant General's office, following the declaration of war, was the establishment of sixteen training camps, following the Plattsburg idea, for the training of young men who could get appointments thereto, to be officers. Such young men had to have flawless health and physique, education, special military knowledge or qualifications which would specially fit them for a commission after training. Twenty-seven thousand young officers were trained in the first three months camp, and have been commissioned. Note that many more received partial training and were eliminated as unfit during the progress of the training. A second course is now in progress, and a third will be started shortly. of officers are civilian experts in khaki and commission, doing magnificent work in their lines, but not equipped to lead or train troops. Those who can both lead and train are what the training camp tries to produce and this kind of officer which must be produced, if, when the national army gets to France, it is not to fail as Russia's army has failed, from lack of proper commanding material. men in training camps is being carried on by the War Department, in order to make each man count for the most that is in him, by assigning him, where practical, to the kind of work he is best fitted to do. Just what this and other war measures dealing with personnel may mean is best seen in the mail records of the Adjutant General's office, in charge of records and correspondence of the War Department. In pre-war days three thousand pieces made a good day's mail. Today 75,000 pieces is below rather than above the average. THE CANTONMENTS The historian of the future will assign a greater place to the bringing into being of the training camps for the national army than they have in the public mind today. Events have moved too rapidly for the reading public to give such constructive efforts their true value. tonment cities, housing half a million men, by the expenditure of $150,000,000 in less than three month's time was a feat which for magnitude and daring, for emergency, efficiency and for American ingenuity, surpassed the building of the Panama Canal, even as the money spent in three months was nearly three times as great as the money spent on the canal in any one year. With all credit to the Army officers who all but gave their lives to this engineering feat, civilian cooperation must receive a large share of praise for what is accomplished. Profits were cut to a minimum. The firms selected to do the construction work were asked to build as they went along, with plans constantly changing, with a labor situation which was sometimes acute and a material situation which was abnormal. Yet, for all practical purposes, sixteen cities capable of holding forty thousand men each — of dining them, housing them, training them, taking care of them, supplying them, with all that a soldier needs, were built, including water, sewer, telephone and light systems, streets, roads and railroads, within less than ninety days. When America called her young to which they could go. Great quantities of raw material have been used in the work. Within sixty days 190 mills, in all parts of the country shipped to the several cantonment sites more than 500,000,000 feet of lumber. Approximately 24,000 freight cars were used for transportation of this lumber. gency cities. Each cantonment contractor has handled about 5,000 carloads of material. Weekly payrolls have run as high as $150,000. pressed that some of the cantonments cost much more than others. The difference, sometimes as much as a million dollars, is easily understood when it is said that where large cities were nearby, so that water supply and sewerage were easy problems to solve, the cost was less — where, because of special fitness of location, a cantonment has been placed far from a large city, a complete water and sewage system has had to be installed — and a water system satisfactory to the Medical Department cost money, as did the sewage system. But the was required to nail down the 6,000,000 square feet of paper roofing for the protection of the cantonment buildings. Altogether 93,000 kegs of nails have been driven and there have been installed 140,000 doors, 686,000 sashes, more than 3,000,000 square feet of screens, 139,000 rolls of sheathing paper and 29,250,000 square feet of wall boarding. street lamps and 20,000 inside lamps have been used at ea.ch site. All of this material was transported during a period of traffic congestion on the railroads. ments was an enormous job. Half a million men require over 12,000,000 separate articles of clothing and bedding alone. Yet they have been supplied as the following cantonments are to be dwelling places for men not accustomed to military life but to all the conveniences of the average American home. Both from the viewpoint of hygiene, comfort and attractiveness the War Department has endeavored to make each cantonment a model city where the environment will be conducive to military efficiency and contentment. anti-war conditions in enlistment and volunteering, and the status of the Army today with its increments by selective, draft brings out some astonishing figures. NUMERICAL STRENGTH So rapidly does the military establishment change today that there is no such thing as a final, or even a very accurate figure. But on ation of war, of which, of course, only a small percentage has been acceptable material. Almost 200,000 have been accepted in the United States kept its Army at home, with the exception of a few officers and men opening up communication in Alaska and in foreign diplomatic service. How becoming a world power affects Army life is well shown in the accompanying is not saying a word. But of course the national army, roughly spoken of as at present consisting- of 687,000 men, is designed for service abroad, and it seems highly probable that a second draft from the ten million registered young men between twentyone and thirty will take place before long, probably filling the cantonments again when the present army shall leave them, trained, for final training and then service in the front line trenches. Making bricks without straw is a problem comparatively easy, when laid side by side with compiling a statistical report without statistics. Yet statistics are the one thing the War Department is determined not to give, for good and sufficient military reasons. Even in the case of dollars it is difficult to get figures which will be final. APPROPRIATION The expenditures by the War Department for all purposes during the fiscal year 1915 amounted to $166,355,172.99. Of this amount, $9,518,227.02 was for the civil establishment, that is, maintenance of the War Department as an Executive Department, buildings and grounds in and around Washington, national and military parks, monuments, national cemeteries, support of national homes for disabled soldiers and sailors, miscellaneous public works, etc.; $45,092,760.02 for rivers and harbors, and the balance, $111,744,185.95, for military purposes, including the support of the Army, Military Academy, militia, fortifications, arsenals, military posts and miscellaneous items. June 30, 1916 Civil establishment (War Department proper). Salaries, contingent expenses, etc. (including office of public buildings and grounds) ....... Civil public works and miscellaneous (exclusive of rivers and harbors) : by recalling the cost of the cantonments— a sum equal to the support of the entire military establishment for 1916. Congress has been anything but niggardly with the Army. It has appropriated lavishly — sensibly, with due forethought and careful consideration, but without stint. The first general deficiency bill after the declaration of war carried $100,000,000 for the President to spend in national security and defense. The army and military bills, with some sundry civil bills, failing in the 64th Congress, were swiftly passed after the declaration of war, totaling nearly four hundred and twenty-five millions. 'Then came the first great war budget which gave $3,281,000,000 to Army and Navy together for war expenses, shortly followed by $640,000,000 for an aviation service and aeroplanes. To cap the climax came the second great war budget appropriating Going a little into detail, it may be mentioned that the Army appropriations for 1918, set aside for the military establishment the regular appropriations which would have been authorized even if the Nation had not gone to war. It carried $273,046,322.50, as compared with $267,596,530.10 for the fiscal year ending in June, 1917. The second, or five billion dollar war budget, after some appropriations for emergency shipping and a hundred millions for naval emergency, devoted most of its total to the Army, as follows : large sums of money wisely. It takes expert knowledge and much economic wisdom, not to defeat the ends of economy by price inflation, while at the same speeding up production and utilizing competition to foster efficiency without allowing it to make waste possible. In this work the Council of National Defense has done a wonderful service as well as in the mobilization of the country's resources and in the expansion of industry to meet new conditions. It has mobilized 262,000 miles of railroad, mobilized the country's means of communication by wire, made an inventory of American industry and instituted a systematic scheme of purchases which has resulted in great economies. As a single instance of the work ir. price economy, it can be said that the council procured 450,000,000 pounds of copper for Government use at a considerable reduction under market price and It has broTight together the greatest corps of civilian, engineering, professional, technical and scientific experts ever assembled and put their services at the disposal of the Government. It has met solve, such as the question of priority in filling orders, prevention of inter-government bidding, drawing the state councils of defense together and making them great war machine, acting as an advisory board on purchases of raw materials and supplies for both America and her allies, etc. It is absolutely impossible to summarize its activities in a paragraph, save to say that if money is the mainspring which makes the war government go, the Council of National Defense is the hair spring by AERONAUTICS It is impossible in a short sketch of this kind to take up and epitomize the work of all the various arms of the service. The Army organization is too vast a machine and its activities too great to permit brief treatment. Its own yearly reports require three large volumes of a thousand pages each, not to mention the thousands of docu- the service might well occupy pages, as far as their intrinsic interest is concerned, it is aviation which is the most spectacular. For there is no blinking the fact that up to the present the United States, the cradle of aviation, has been most laggard in Army development of flying, and this in spite of the fact that it was the Signal Corps trials of 1908 and 1909 which established the heavier-than-air machine as a factor in warfare. Now we have an appropriation of $640,000,000 for an aviation service, and the strong probability that it will be increased by as much more in the not far distant future. And the story of the building of this service, when it is told, will be a real American romance. The home of aviation was, within a few months, absolutely destitute of anything pertaining to the art, at least as far as war preparations were concerned. No factories, no aviators, no workmen, no engines, no industry to start with — the and build some twenty thousand air planes, train enough aviators, observers, mechanics, balloonists, photographers, bomb droppers, etc., to man the planes and — in effect, go and put out Germany's eyes. Factories have been developed. Men are being trained. Planes are being manufactured — the money ig being spent and something is being received for it. The types of airplanes now in process of manufacture cover the entire range of training machines, light highspeed fighting machines and powerful battle and bombing planes of the heaviest design. Our contracts call for an ample number of training machines and embrace as well giant battle planes capable of the work of the Caproni, the Handley Page and similar types. been taken that the American forces in France shall be amply equipped with aircraft. The work of the Aviation Section has been thoroughly systemized. The training of aviators, the building of motors and the construction of and with general war plans. The comprehensive plan is that, when motors are ready, there shall be ready also the planes necessary; and, when the motors and planes are ready, aviators and machine guns shall be available. Co-ordination has been developed in every branch of the Aviation Section. matter of aeronautics is greater than in almost any other military branch. Censorship is rigid, and particulars, even when known, are not published. It is impossible to say more of the actual progress made than to state that contracts have been let and work is in progress on practically the entire number of airplanes and motors for which provision was made in the $640,000,000 aviation bill passed by Congress in July. Nor have we had to do this, to use new and strange work alone. More than thirty of the air service experts of the Allied nations have come to Washington and are on regular duty with the officers of the Army and Navy air services and with the members of the Aircraft Production Board. The best men of the air services of the Allied countries have been loaned to this Government and were sent here to aid in getting our aviation program under way with the fewest, possible mistakes and the greatest economy in time. Of course, production in quantity is biit one step in the program. Aeroplanes without accessoriescameras, bomb droppers, barom- thousand and one things which make up an aviator's equipment — would be of little use. These, too, are being cared for, and production speeded to the necessary point. So is the production of aviators. This country has an unlimited supply of young men possessing courage, self-reliance, good judgment and decision — the things required in the air service. This service, appealing to both the imagination and patriotism of such young men, is today fitting thousands of Americans for flying. The ground schools conducted by several of our great universities are turning out cadets steadily. Twenty-four flying schools have been authorized and construction work is up to schedule. Allied THE ARMY countries accept our cadet students for final training upon foreign soil. These men are being1 trained in our uniforms and will be turned over as finished aviators to the fighting forces in France. American aviators are today in training in all the Allied countries. They are nowundergoing intensive training behind several of the battle fronts. The sending of great numbers of American aviators abroad and the rapidity of training preparations at the flying schools in the United States — such as the one near Dayton— indicate the scope of the Liberty Motor. And mention is about all it can get, for no details in the whole chest of War Department secrets have been more closely guarded than these. Absolutely mercially "in production" — that is, made in quantity by standardized methods, instead of slowly and by hand finishing, as all other good It is the result of the labors of America's foremost engine experts, and is said to be not only satisfactory as a motor, but to have a greater horsepower per poundage than even the best foreign type. Of it, Secretary of War Baker has said: Engine' has passed its final tests. They were successful and gratifying. The new motor, designated by the Signal Service as the 'Liberty Motor,' is now the main reliance of the United States in the rapid production in large numbers of highpowered battle planes for service in the war. In power, speed, serviceability and minimum weight the new engine invites comparison war has produced. "I regard the invention and rapid development of this engine as one of the really big accomplishments of the United States since its entry in the war. The engine was brought about through the co-operation of more than a score of engineers, who pooled their skill and trade secrets in the war emergency, working with the encouragement of the Aircraft Production Board, the War Department and the Bureau of One in each Regular Army National each in the Philippines, Panama, and Hawaii. One each at Ft. Bliss, Tex., Ft. Sam Houston, Tex., and Chickamauga, Ga. / \| O the casual visitor at WashI ington, the Treasury is, outside, a beautiful example of architecture and, inside, a bewildering succession of offices, vaults, cages and rooms with people and money in them. He is taken by a guide to view monetary exhibits BIN AT THE TREASURY which pass his comprehension, perhaps sees the interior of a vault with more wealth than Midas ever dreamed of, and leaves with the confused impression that his Uncle Samuel is very rich indeed, but As a matter of fact, the activities of the Treasury Department are so varied and so numerous that only by a careful study of the laws under which it operates or a reading of its huge reports can any adequate idea be gained of its work. As for Uncle Sam's money and the way it is taken care of, it may fairly be stated that no visitor to the Treasury really gets any adequate idea. For instance, how much money is there in the United States? Not wealth — money and wealth are entirely different. How many people, uninformed, will guess that, if the United States had to depend only on its money, and not at all on its wealth, it could pay its own expenses but for two years before going broke? Yet such is the case. The general stock of money in the United States June 30, 1915, was $3.989,400,000. Of the total stock, $420,200,000, or 10.53 per cent, was in the Treasury as assets. Coin and other money in national and other reporting banks, exclusive of those in the island possessions, amounted to $1,448.600,000, and, including $312,100,000 cash in Federal Reserve Banks, the sum of $1,760,700,000, or 44.14 per cent of the total stock of money, was held by banks, the remaining $1,808,500,000, or 45.33 per cent, being outside of the Treasury and banks. The amount in circulation, exclusive of coin and other money In the Treasury as assets, is $3,569,200,000, or $35.44 per capita, an increase of $167,200,000 and a per capita increase of $1.09 over 1914. how this money is distributed. Of the total money in circulation, $1,662,981,438 is in gold coin and certificates, $414,961,583 is United States notes, Treasury notes and Federal Reserve notes, $785,393,047 is in National Bank notes and $705,883,506 in silver coin and certificates. Thus nearly half (46.59 per cent) of our money in circulation is gold or its representative. AND COIN Except on the Pacific Coast, where coin is still preferred to paper, the bulk of all monetary transactions of ordinary life is accomplished with gold or silver certificates, bank notes or the like. Held in some suspicion when first authorized (February 25, 1862), the familiar "greenback" is in the public mind to-day "as good as gold," even greenback in their hands, calling for a silver dollar, there actually is a silver dollar waiting for them — or for whoever calls with the "bill" to ask for it — in the vaults at Washington. In the first years of the war, when the "greenbacks" were first made legal, the total amount authorized was $450,000,000 ; the highest amount outstanding at any time was $449,338,902, on January 30, 1864. out in the table on page 296. It must not be supposed, however, that this sum, in circulation and constantly redeemed and reissued, forms the bulk of the redemption work done at the Treasury. National Banks issue notes which have to be redeemed, and the size of this financial undertaking may be imagined when it is stated that the COUNTING COINS BY MACHINES By the canceling and retiring of these notes as they were received in the Treasury, the amount outstanding was reduced more than $100,000,000 when the process was stopped in 1878, Congress requiring the notes to be reissued when redeemed. At that time the amount outstanding was $346,681,016, and it has not been changed since. Bank Redemption Agency during 1915 was $782,633,567, the largest for any year, and an increase of $75,876,965 over 1914. Of the amount received, 46.53 per cent came from banks located in New York City. The number of packages was 45,532, containing 76,287,975 notes, with an average value of $10.03. Payments for notes redeemed was made as follows : By Treasurer's checks, $122,230,578; by remittances of new United States currency, $307,667,490, and gold, silver and minor coin, $28,220; and by credit of $340,482,729 in various accounts. The notes assorted and delivered amounted to $764,926,023, of which sum $130,389,450, or 17.05 per cent, was fit for use and was returned to banks of issue in 92,952 packages. The remainder, $634,536,573, or 82.95 per cent, was delivered to the Comptroller of the Currency, $330,110,347.50 in 191,068 packages, as unfit for use, to be destroyed and replaced by new notes sent to the banks of issue, and $304,426,225.50, in 25,839 packages, for destruction and retirement from circulation against deposits for that purpose. Securities to be destroyed are delivered to the so-called destruction committee, composed of representatives from the Secretary's Office and from fiscal bureaus concerned. Some idea of the amount of work handled by. this committee may be had from the fact that during the year just closed 377,364,188 redeemed notes (paper money) of a nominal value of $1,541,131,111, were destroyed, as well as large quantities of other securities. counted, the count verified, the paper cut in pieces or punched and the pieces then fed to a macerating machine, which, with water and power, makes a pulp of what once was But a "bill" is not destroyed without cause. Formerly any soiled or creased bill sent in was condemned, a new one put in its place, and the old one destroyed. Now, however, Uncle Sam has a wonderful moneylaundering machine which washes, resizes, dries and irons out paper currency unfit for circulation but not yet torn or badly worn. The result is a "bill" hardly to be told from new. There are laundering delphia and Chicago. Naturally, it takes fine paper to stand washing — and, indeed, no finer paper than that used for "greenbacks" can be bought. Printing, a branch of the department, designs, under the direction of the Secretary, engraves and prints the notes and certificates complete. This currency is delivered to the Treasurer in packages of 4,000 notes, pense attending making, issuing and the redeeming of paper currency, the average cost is as follows : "greenback" into circulation. And it is staggering to find the total cost for redemption of 299,455,985 pieces, and issuing of 280,174,317 pieces (1915) to total $4,316,626.44 in this year. But a curious little fact commends itself to the thoughtful. Though it costs this sum to issue and redeem paper currency, that sum is more than saved by the prevention of abrasion of gold and silver coin. If we had not the notes, we would FREdTTENTLY LOANED TO EXPOSITIONS It is interesting in this connection to know that the life of a United States one dollar note averages 3.14 years, while the five dollar note averages 2.73 years. The average life of all denominations of United use the coin. The Government saves the loss by abrasion by letting paper be "abraded" and keeping the coin in its vaults. Think it over! lie knows every day just where he stands. And curious though it may seem, his whole balance sheet may be written on a page smaller than that required for the same information of many a big private industry. money comes from, when it arrives in the Treasury, and just where it goes to when it is paid out. The sheet covers years 1914 and 1915. act of July 11, 1862, and its first work was an attempt to apply machinery to the trimming and separating of Treasury notes, such notes having been printed by private bank note companies and then forwarded to Washington for signature of the Register of the Treasury, and the Treasurer of the United States. This work, however, soon became physically impossible for these officers to perform and a large corps of clerks was employed for this purpose. This was very expensive, and to obviate it authority was granted by Congress to have these signatures engraved in the plates and the seal of the Treasury imprinted on the notes, and steps were taken to procure the necessary machinery to perform this work of sealing in the Treasury Department. Following the successful execution of this work, it was determined that an effort should be made to perform, under official supervision, the entire mechanical work upon United States securities, and authority therefor was granted by the act of July 11, 1862, which authorized the Secretary of the Treasury, in case he deemed it inexpedient to procure such notes by contract, to cause them to be engraved, printed and executed at the Treasury Department, and as prior to the passage of this act none of the public securities had been engraved or printed otherwise than by private contract, this act may be re- Bureau of Engraving and Printing. From time to time following this date the work done by private companies was gradually absorbed by the bureau until all of the printing of the securities of the Government was done at that bureau, and the last work taken over by it from private contractors was the printing of the postage stamps which the bureau undertook in 1894. The bureau is the Government factory for producing its paper money, bonds, revenue, postage and custom stamps, checks, drafts and all important documents printed from engraved plates. The output in the fiscal year just ended, June 30, 1916, had a value of approximately 3% billions of dollars. Putting it in a more concrete form, the daily output of United States notes, gold and silver certificates and National bank notes, is two and onequarter million notes, having a face value of nine million dollars, and weighing over three and one-half tons. If laid out flat they would cover nine acres, and if placed end to end the daily output would make a chain two hundred and fifty miles long. stamps are manufactured, which would cover approximately seven acres, or make a chain of stamps six hundred and twenty miles long. The value of each day's output is nearly seven hundred and fifty thousand dollars. Six hundred em- ployees are engaged in their manufacture. Fifty -one different kinds of postage stamps in denominations from one cent to five dollars are made for the United States and its insular possessions. They are printed in fifteen distinctive colors. Another important part of the Bureau's work is internal revenue stamps, through which an annual income of over five hundred million dollars is collected for Uncle Sam. These stamps are of larger sizes than postage stamps and while the daily output is only twenty million stamps, they would cover twenty acres if spread out in single sheets and weigh six and one-half tons. More than three hundred different varieties are issued. It is a noteworthy fact that such enormous quantities of securities are produced year after year at this establishment without the loss of one cent to the Government, "and is a testimonial to the integrity and ability of the employees, not one of whom is bonded, as well as to the efficiency of the system under which they operate. Be it further said to the credit of these employees that not one has ever engaged in the counterfeiting of the securities manufactured by this bureau. The bureau employs the most expert designers, engravers, plate printers and other artisans requisite to a large plate printing establishment, several of whom entered its service during the Civil War shortly after the bureau was organized, and who are capably occupying positions of trust and responsibility. The number of employees in the bureau engaged in the making of paper money is 2,800; in making postage stamps, 600 ; in making revenue stamps, 600, and about 100 in making bonds, checks, commissions and various other classes of work; the total number of employees being 4,100; 2,200 of whom are females. The maximum and minimum per annum. An idea of the business growth of the United States may be gleaned from the fact that the Government Bureau of Engraving and Printing delivered 11,771,283,150 perfect postage stamps during the fiscal year 1916. The paper required for this work amounted to 1,100,000 pounds, and to make this paper 4,500 large pine trees were ground to a pulp. Had these trees been converted into lumber, 85 well-appointed bungalows could have been built. The paper itself would make an edition of 3,500,000 twelve-page seven-column newspapers. As the stamps were printed from intaglio-engraved plates in which the entire surface is covered with ink and wiped with a cloth that leaves the ink only in the engraved lines, the amount of ink required was 625,000 pounds. But only 10 per cent of this was actually applied to the stamps, the balance being wiped off. The gum on the back of the stamps is made by scientifically roasting the highest grade of tapioca flour, such as is used for making pudding, and as 350,000 pounds were used, all of the inhabitants of a large city would have been given their fill of tapioca pudding for one meal with the material used. The sheets of one hundred stamps each, as sent to the post offices, piled upon each other, would make a shaft over six and three-fifths miles high, and placed end to end would make a strip 16,500 miles long, and as there are ten rows of stamps in each sheet, a strip of single stamps would be 165,000 miles long, and would girdle the earth six times, with something over. which embraces checks, drafts, bonds, paper money, revenue, customs, parcel post and postage stamps and certificates of deposit for the Post Office Department It has been our constant endeavor not only to safeguard our stamps and circumvent their counterfeiting, but to make them really artistic. When you comprehend the small at the results we obtain. ! The engraving division is the cornerstone of the bureau and the bulwark of our securities. In this division 'every form of security has its origin, and the most artistic and skilled engravers that the world produces are employed here. Steel engraving is the perfection of art as applied to securities; it differs from painting and sculpturing, inasmuch as the engraver who carves his work on steel plates must deliberately study the effect of each infinitesimal line. Free hand with a diamond-pointed tool, known as a graver, aided by a powerful magnifying glass, he carves away, conscious that one false cut or slip of his tool or miscalculation of depth or width of line will destroy the artistic merit of his creation, and weeks or months of labor will have been in vain. In no other form of printing can the beautiful, soft, and yet strong effects in black and white be obtained as in steel engraving. The introduction of cheap mechanical process work has superseded the beautiful creations of our master engraver commercially, and now we find the art limited to the engraving of securities as applied in the Bureau of Engraving and Printing. The work in this division is classified and divided so that the engravers become specially skilled in some particular branch of the art. For instance, they are classified as portrait, script, square letter and ornamental engravers. Each is confined to his own specialty, and thus becomes unusually expert, the result being that not only better work is secured, but a greater amount is turned out in a given time, and what "j of greater importance, increased security is obtained. The individual excellencies and characteristics of a number of men are impressed upon every stamp issued. Therefore, it would be as difficult for one engraver to make a perfect reproduction of a Government plate as it would be for the reader to reproduce an absolute facsimile of his or her own signature, and, strange as it may seem, no one has yet accomplished this feat. To the credit of the engravers and employees of this division, it should be stated that in the history of the bureau none of its employees has ever engaged in counterfeiting. When it is determined to issue a new stamp, the matter is discussed by the officials having in charge the several branches of the service involved, and the conclusions reached are embodied in a model made by a trained designer, which is submitted for the criticisms of the officers who discussed the matter in the first place. The model is then modified in accordance with the criticisms, and is finally approved by the Postmaster General. The approved design is placed in the hands of the engravers who cut it upon a small piece of annealed steel. After the approval of a proof of this engraving, the piece of steel is heated red hot in cyanide of potassium and hardened by suddenly dipping it into oil and water. This single engraved subject is duplicated four hundred times upon the larger plates that the stamps are printed from, by means of the transfer process. This is a method of reproducing engraving devised many years ago by Jacob ' Perkins, an inventive American, who may be Considered the father of the present method of duplicating bank note and stamp plates. It consists of making a reversed duplicate or mold of the original engraving by rolling a soft, annealed steel roll upon it in the transfer press. Being accurately guided and held by the mechanism of this press, continued rolling under high pressure forces the soft steel of the roll into the engraved lines of the original design, and forms an exact counterpart, in relief, of it. This roll, being hardened, is used to duplicate the engraving by the same process, upon a soft steel plate, which it will do a great number of times before wearing out, reserving the original engraving, or die as it is called, for making additional rolls. The original engraving is never printed from except to make what are known as die-proofs. The paper, being printed wet, Contracts on drying, and the mathematically correct layout of the engraved plate bears only an approximate relation to the desired printed sheet. The paper we print to-day will vary in shrinkage from that we print to-morrow. As the physical properties of the tree govern the expansion and contraction of the paper made therefrom, no two sheets are exactly the same size. The actual difference in size of the individual stamp is too minute to be readily discernible, but becomes a serious factor when the row is twenty But that is not all. To smooth the paper for the operation of gumming, it is subjected to 500 tons pressure in a hydraulic press, and if very dry, it stretches but little, but if the day is damp and humid it stretches perceptibly. The contraction of the gum itself is a factor, and the atmospheric conditions still another. Our perforating machines have not human intelligence, and they blindly perforate the sheets alike until their adjustment is changed. Therefore, the best we can do is to average the adjustment and it is only by chance that all the perforations are exactly central. Of course, it will be understood that typographic printing, being done on dry paper, eliminates many of these problems, and no great feat is performed in perfectly centering the perforations on a dry printed stamp. press." Four plates are used in order that the operation of inking, wiping, polishing and taking the impressions may be done simultaneously. This press requires the service of a printer to polish the plates, one girl to lay the sheet in position and another girl to take it off after printing. After each two hundred sheets are printed, they are counted and dried. To secure a flat surface for subsequent operations, they are pressed in a hydraulic press. They are next gummed by passing beneath a glass roller which is bathed in a solution of dextrine .(which forms the gum), and the sheets are then carried by grippers through a drying chamber in which the gum is dried in less than thirty seconds. Just before leaving the gumming machine, the sheets are carried through a device that breaks the gum into innumerable cracks and materially prevents subsequent curling. The printed and gummed sheets of 400 stamps are now fed through a rotary perforator that perforates the stamps in one direction and cuts the sheets in half. Another perforator of the same construction perforates the stamps crosswise and makes another cut, thereby quartering the original sheets. After a close and rigid inspection, these sheets are counted and made into packages for final packing for shipment to the post offices. The new building for the use of the Bureau of Engraving and Printing has been occupied since early in the spring of 1914. This building is the most modern type of factory building in the United States. While the exterior of the building is classic and monumental in style, the wings, which are utilized for factory purposes, are constructed along modern factory lines. long, fronting on Fifteenth Street, with a depth of about 296 feet and a height of 105 feet. It has a basement, four stories and attic, and is in the form of the letter "E," but with four wings instead of three, making three open end courts, two of which are approximately 230 feet long to the end of the wing. The two inner wings, to allow space for the driveways, are about 30 feet shorter. There is a mezzanine gallery on each floor, having a total length of about 1,800 feet on all floors where installed, which is used by the public for viewing the more interesting operations of the bureau, and this may be done without the possibility of any loss of a security or interference with the workmen. None of the employees are permitted to leave the building during the lunch hour, as each individual employee is held accountable for the securities which he or she is handling during the working hours, and to permit them to leave the building would necessitate a check or count, which would be too expensive. opened its doors at 30 Wall Street in 1854. It occupied the same historical building until its age made its demolishment necessary in 1914. In 1910 a new eight story building was built adjoining the old in the rear, and with an entrance on Pine Street. Since that time its operations have been carried on there. Appropriations have now been made by Congress for the erection of a new building on the site of the old Wall Street building, to be joined to the present Pine Street building, so that for the indefinite future the office will continue its service from the same historic site on which it started. From deposits of a few thousands in value in 1854, the importance of the office has increased to such an extent that for the fiscal year 1916 the aggregate value of the deposits received and handled amounted to the huge sum of $325,958,585.38. Of this $321,609,643.73 was gold and $4,348,941.65 silver. $253,957,895.26 was from foreign countries and $72,000,690.12 from the United States. The number of deposits made was 17,338. During the year 149,867 assays were made. The Assay Office is the great purchasing, as well as selling, agent for gold for the Government. It is the station where the crude wealth produced by our own mines, and the wealth that all the world sends to our shores in the ordinary activities of commerce, is converted into cents. We purchase gold in any amounts from $100 in value up — in any form suitable for mint purposes and from any source. We receive gold dust from Alaska and Dutch Guiana; bullion from Mexico, South and Central America ; gold and silver coins from all the countries of the world : old gold and silver jewelry from pawnbrokers and jewelers ; fine gold bars and mixed bullion, and light weight and mutilated United States coin. The purchase is made at the actual gold value at the uniform rate of $20.67 per fine ounce. Silver is paid for in fine silver bars, which, in turn, are marketed by the depositors at the current price in the open market. The process by which the crude bullion is turned into fine metal is itself an interesting one. The office is divided into four general departments : the Deposit and . Weigh Room, where the metal is first received, weighed and melted ; the Assay Department, where its value and fineness are determined ; the Melting and Refining Department, where it is refined and cast into fine bars; the Clerical Force, where the calculations are made and final payments provided for. Immediately upon its receipt the deposit is weighed and at once sent to the Deposit Melting Room, where it is melted and thoroughly mixed and cast into bars. From the liquid metal samples are taken during this melting from which the assays are made. These determine the proportions and fineness of the gold and silver contents. The melted deposit is again weighed in the Deposit Weigh Room, its values determined by the assays made from the samples previously taken, and payment made by check by the Superintendent drawn on the Treasurer of the United States. The bar of mixed gold and silver is then turned over by the head of the Deposit Weigh Room to the Superintendent of the Melting and Refining Department. Here it is again melted and cast into thin slabs or anodes about 18 inches long and ^4 inch thick of about the composition of two thirds silver and one third gold. These anodes are put in a muslin bag and are hung in a solution of silver nitrate and free nitric acid opposite a strip of pure silver called the silver cathode. Electric current is passed through and the silver passes from the anode to the cathode in pure silver crystals. It is scraped off into huge earthen jars and then taken to the melting room and cast into its final form of fine silver bars. The residue remaining in the muslin bag is taken out, washed and in turn melted and cast into smaller anodes, or slabs, which in turn are taken to the gold refining room and by a similar electrolytic process the fine gold extracted. The gold is then in the form of a warty, irregular slab of gold. This in turn is for the vaults or for trade purposes. During the refining process the base metals and by-products are taken into solution and are later precipitated by chemical reaction and recovered. When it is realized that the ordinary deposit in its course through the office is melted five times; that not less than five and often seven or more assays are made of it ; that each bar is stamped with five separate stamps ; that it must be constantly weighed and re-weighed and checked and re-checked ; some conception may be had of the care and attention to detail required in the office. Experimental work, looking to the discovery of better and more efficient methods, is being constantly carried on. The office uses the most perfect appliances obtainable for its work and seeks constantly to increase the efficiency and perfect the products of its labor. the recent almost phenomenal growth of its financial power, the importance of the work of the Assay Office, as related to the financial and business world, constantly increases. It is now the largest and most completely equipped office of its kind in the world and through its doors is destined to pass in continuing volume the golden stream that will make the United States the financial master of the world. IN the operation of providing coinage for the country the Government purchases the gold bullion from anyone who offers it for sale at the rate of one dollar for each 23.2 grains of pure gold, or about $20.67 per ounce, and silver at the market quotations when requested. This bullion, if in an unrefined state, is refined and separated from all foreign matter. It is then sent to the mint and delivered to the superintendent of the melting department. Nine parts of pure gold or silver are mixed with one part of copper (alloy) and the mixture melted in crucibles placed in the gas furnaces. It is then poured into molds and produces ingots about 12 inches long, 1% inches thick, and from 1 to 2 inches wide, depending upon the denomination to be made. Granulations of these ingots or melts are taken and sent to the assaying department and assayed for their fineness. If found correct, the ingot is stamped with the number and fineness of the melt ; if not correct, it is condemned and remelted. This then places the responsibility for the legal fineness of every coin upon the assayer. The ingots passed by the sissayer as correct are then delivered to the superintendent of the coining department. The superintendent of the coining department upon receiving the ingots from the superintendent of the melting department passes them steel rolls, eighteen or twenty times, depending upon the denomination, each driven by a fifty horse-power electric motof, each draft reducing the thickness, and adding to the length of the strip until the last draft leaves it of such a thickness that a coin of the desired denomination cut from it will weigh as nearly the right weight as it is possible to roll. After rolling the ingot to the required thickness of the coin, or denomination required, it is put through the cutting machine where the blank, or planchet, is punched out, leaving the clippings to be returned to the melting room, there to be re-melted and returned to ingots. The gold planchets or blanks are then sent to the weighing room, where they are passed through the automatic weighing machines. In practice it is impossible to cut all the gold planchets so that they will each weigh precisely the standard weight, therefore, the law permits a tolerance or variation of the weight from standard of one-half grain on double-eagles and eagles, and one-quarter grain on half and quarter-eagles. The machines, known as automatic weighing machines, then weigh each of the planchets separately, and a machine known as the shaving machine and reduced to within the limi^ of tolerance, one-half or onequarter grain, depending on the denomination, to good "heavies" onehalf and one-quarter grain above standard. Those that are found too light are condemned and go back to the melting pot. After coinage, all coins are again re-weighed. At this stage the metal, after going through the various operations, is very hard, and, before it can be stamped, it is necessary to anneal or soften the same, otherwise it would be very destructive to the dies when the piece is being struck on the coining presses. The Wanks are placed in a gas annealing furnace, where they remain in the retort until they become a "cherry red," when they are dropped from the furnace into water to keep them from oxidizing. After coming out of the water they are cleaned in a weak acid solution and dried out in centrifugal machines. They are then sent to the milling or upsetting machines, where the edge is turned up on the blank. The blanks are now bright and soft and ready for stamping or coining. In the coining room they are fed into the coining presses by automatic feeders, and the automatic fingers on the presses take one piece at a time from the bottom of the tube attached to the automatic feeder and place it between the dies, at the same time pushing the finished piece out and dropping it in a screened box at the side of the press. The upper and lower die being respectively the obverse and reverse sides of the coin, in this position it drops automatically into a collar which is internally engraved to conform to the edge of the coin, known as the reeding; at that instant the dies approach each other under a pressure of one hundred tons to the square inch, and the planchet is pressed so that the metal is driven into every corner and crevice of the engraved die, and at the same time outward into the engraving on the interior of the collar producing the reeding or rough edge. This enormous pressure is regulated by adjusting screws, which determine just how close together the two dies, upper and lower, will be brought to each other, and this adjustment is made so they shall come just close enough together to bring out every detail of the engraving. This coinage operation proceeds at the rate of from 90 to 120 pieces coined per minute, on one press, the speed of operation being adjusted according to the size of the press. There are in the Mint at Philadelphia twenty-four coining presses of three different sizes. After stamping, each coin is separately inspected and weighed. Six automatic inspecting machines are in use. Each machine is operated by two women who have a view of each side of the coin as it passes through the machine. The weighing is done on the automatic scales. The law permits a variation of one-half grain on double-eagles and eagles, and one-quarter of a grain on half and quarter-eagles, and one and a half grains on all silver coins, from the standard weight. The pieces that weigh above or below the standard mark are kept separate. The condemned are rolled out and sent back to the melting pot. Owing to the greater tolerance (one and a half grains)- on silver the blanks are rolled close enough to eliminate all weighing, but after coinage the pieces are weighed the same as gold. After weighing and separating the coin is counted by weight and placed in sacks ; the gold in $5.000.00 packages and the silver in $1,000.00 packages, and delivered to the superintendent, who places it in vaults sub- ject to orders from the Treasurer, Assistant Treasurers and banks. All metals are delivered to the superintendent by weight as well as value. Gold and silver coin and bullion are received and delivered at 1,000 fine ounces and minor metals and coin at troy ounces. At the end of the fiscal year, i. e., June 30th, the total weight of all the ingots delivered to the coining department by the superintendent during the year stands charged against said department and the total weight of all the good coin, condemned coin, clippings, sweeps, etc., that have been delivered back by the coining department to the superintendent are placed to the credit of the coining department. Theoretically, this is supposed to balance, but if it does not the superintendent of the coining department will be held responsible for the shortage. However, in practice, the law recognizes the \itter impossibility of putting such an enormous quantity of metal through all the different operations without a certain amount of loss or wastage, and this legal allowance on gold is 1/2000 part, or for every 2,000 ounces operated upon one ounce may be lost in wastage before the coining department is held responsible. On the same would be two ounces. The actual wastage in the coining department under the new system of cleaning does not average more than five per cent of the legal allowance in gold and ten per cent in silver. During the fiscal year ended June 30, 1013, the Mint at Philadelphia coined $19,678,227.50 in gold and the loss or wastage on this amount was 14.289 ounces, of the value of $284.12, and $1,936,199.75 in silver coin on which there was a loss or wastage of 22.05 ounces, of the value of $12.24, or a total value of $296.36 in gold and silver. This loss covers the workings of an entire year of $21,614,427.25. The legal percentage of wastage to the amount operated upon was gold, 1.37, and silver, 1.84. The precautions to guard against any possible loss by carelessness on the part of the employees during the process of manufacture are about as near perfect as human ingenuity can devise. At the opening of the day, the metal is weighed and charged to the various departments and a settlement of the same is made each day before the close of work. In the morning the entire weight of the metal that stands charged to the coining department on the superintendent's books constitutes the coining department's opening balance. Every ounce of metal that is distributed among the various departments is charged to that department, and at the close of business for the day is weighed, and, if found correct, the account with the various departments is closed and the metal locked in the vaults. A detailed statement of the workings of each department, showing the amount operated upon, finished and unfinished, together with loss and wastage, is sent to the office of the superintendent of the coining department, where a tabulated record is kept from day to day. It shows by the size of the operation if the loss exceeds the legitimate loss in any one department by even less than one piece. If the loss is excessive, then the employees in that department are kept until the shortage is accounted for, or the error in calculation discovered. It generally happens to be an .error in figures, or a coin or box of coin had been overlooked. On the whole it is rare for the question to arise. Once in a while in an extraordinarily large operation there might be a legitimate loss equal to the weight of a single piece in excess of the estimate of what the loss should be, and this would remain unaccounted for except as legitimate loss. It would be out (if the question for any considerable theft to be committed or even to conduct a systematic pilfering on a small scale without the culprit being discovered in a short time. The daily record of the day's workings kept in the superintendent of the coining department's office shows the loss or wastage on every operation. The scales used for the weighing of bullion, coin, and metals will weigh from 1/100 part of an ounce up to 10,000 ounces at each draft. When the coin is finished and counted it is delivered daily to the superintendent in sacks containing $5,000 in gold and $1,000 in silver in amounts that may have been coined the day previous. Out of every delivery of finished coin to the superintendent, there is taken at random by the assayer and superintendent one piece for each 1,000 pieces of gold, and one piece from each 2,000 pieces of silver, which are locked in what is known as the "pyx box," the superintendent or his representative holding the key to one combination, and the assayer the key to the other combination. Each year in February as assay commission, consisting of twelve or fifteen leading and representative citizens from all parts of the United States, the Judge of the United States District Court, Comptroller of the Currency, and the Assayer of the United States Assay Ofiice in New York, are appointed by the President. The last named are ex-offlcio members of the Commission. He selects men who are expert chemists, scale makers, coin specialists, financiers, professors and lawyers. They meet .at the Mint in Philadelphia, organize themselves into committees on counting, weighing and assaying and these committees open the "pyx box," count, weigh and assay a large number of the coins and report the result to the President. In case any of these coins are found outside the legal limit of weight or fineness, it would be sufficient grounds for the removal of the operative officer or officers. Prior to the delivery of coin to the superintendent and before the assay pieces are taken out, the latter, by the trial separately of not less than five pieces for each 1,000 pieces embraced in the proposed delivery, must satisfy himself that the coins are within the legal limits as to the weight. If these trial pieces prove satisfactory the delivery is made, and if not satisfactory all the coins are weighed separately and such as are not of legal weight are defaced and delivered to the superintendent of the melting and refining department. As an additional precaution, from the first and two subsequent deliveries in each week of gold and silver coins of each denomination of coin delivered by the coining department two specimen pieces are taken at random, certified and enclosed by the superintendent and assayer (in the same manner as above prescribed for the Annual Assay Commission), and promptly forwarded to the director of the mint by registered mail for assay by the assayer of the Bureau of the Mint. Metals required for the manufacture of minor coins, that is, five cent nickel and one cent bronze pieces, are purchased by the superintendent of the mint, with the approval of the director of the mint as to price, terms and quantity, after public advertisement, as provided by law. The metal so purchased is delivered to the melting department where it is converted into ingots 23 inches long, 4% inches wide, and % of an inch thick of legal alloy. The five cent piece,, or nickel, contains 75 per cent of copper and 25 per cent of nickel, and the one cent bronze piece contains 95 per cent of copper and 5 per cent of zinc and tin. These ingots are delivered to the coining department, where they are passed through heavy sixteeninch rolls and reduced to the thickness of the coin. About fifteen passes are required to make this reduction. Starting with the ingot 23 inches long, the strip is rolled fifteen feet and then cut in two. Each of these strips will be 12 feet long when finished. The strips are then put through the cutting machines, where six blanks of bronze, or five blanks of nickel are punched out. These presses make 170 revolutions per minute and in that time punch 1,020 bronze blanks, or 850 nickel blanks. These blanks are passed through rotary annealing furnaces in order to make them soft and malleable before stamping. From the annealing furnace they are placed in tumbling barrels for the purpose of cleaning and brightening, and rolled in a solution of our own devising for about half an hour. No acid is used. After tumbling, or rolling the blanks are thoroughly washed and then dried in centrifugal machines. No sawdust is used in this operation. The blanks are selected and milled. The finished blanks, or planchets are taken to the coining room, where they are stamped and inspected, after which they are counted and placed in ready for delivery. No pyx or special assay coins are taken from the minor coin. The tolerance on these pieces being much greater than on gold and silver, no adjusting is required. A separate plant for the minor coinage, remote from that used in the coining of precious metals, has recently been fitted up in another part of the building. This- plant is equipped with heavy machinery, and is capable of turning out a greater percentage of coin at less expense. A separate plant also adjoins the minor coinage plant. It is known as the medal room. It "is equipped with four of the latest improved hydraulic presses and other suitable machinery and appliances for the manufacture of medals and proof coin. Here are made gold, silver and bronze medals for the Government and private parties. Gold and silver medals are made from fine gold and silver. the engraving department of this mint All dated dies and all other coinage dies which have been in use are destroyed at the end of the calendar year. The engraver is the custodian of all dies. The operative officers in their accounts with the superintendent are charged and credited with deliveries of bullion or coin by weight and the account kept in fine ounces. Troy weights are used, while metric weights are by law assigned to the half, quarter 'dollar, and dime, 15.432 grains being considered as the equivalent of a gramme. The above figures include the cost of ingot assays, ingot melting, the entire coining department and all of the superintendent's department net expenditures. During the year all sweeps, rags used in cleaning machinery, wash water, etc., are gathered and placed in a large iron vessel, the water evaporated and the residue burnt. After being dried the residue is taken to the sweep cellar where it is passed through a jaw crusher which reduces the sweeps to one inch or less in diameter, then through a mill with sixty mesh screens which grinds the sweeps under water until they are fine enough to pass through the screen to the two settling tanks and a steam drier. The type of mill is a standard mining machine where the rolls and the pan remain stationary. It is of sufficient size to make it unnecessary to keep the mill in continuous operation and thus the men are available in other places. The drier constantly agitates the wet sweeps, so that they cannot bake on the bottom. One settling tank is directly above the other and the lower contains a steam syphon which lifts the water to the upper. From the upper tank a connection leads the water back to the mill so that it may be used over again. After being thoroughly dried the sweeps are barreled, samples taken therefrom and assayed. Afterwards they are sold to the highest bidder. During the ten years ended June 30, 1913, this mint coined $362,824,125.00 in regular domestic gold coin, $60,069.00 in Lewis and Clark gold dollars, and $14,9r>3,488.38 in foreign (Mexican) gold coin, $7,041,294.65 in foreign silver and minor coin, $41,185,228.95 in domestic silver coin, and $24,477,958.21 in five cent and one cent pieces, making a total coin- , age of $450,542,164.19, or 1,547,431,704 pieces. Upon this large coinage the wastage or loss was gold, $18,491.93; silver, $12,129.15, and five and one cent pieces $4,346.22, a total of $34,967.30. The average coinage per year was $45,049,441.60 and the average loss or wastage was $3,496.73. Since the elimination of acid for cleaning purposes and the introduction of the new cleaning method the wastage has been reduced one-half. The last three years show a very coinage of gold and silver has fallen off considerably; the former due to the passage of an act authorizing the issuing of gold certificates on gold bars instead of the coin as heretofore, and the latter owing to a large surplus of subsidiary coin in the vaults of the Treasury and subtreasuries. On the other hand, the demand for minor coins has in- and one cent pieces. A complete system of cost-keeping shows the cost of each process in coinage operations per ounce of metal handled, and per dollar of product; calculations are made If the seigniorage on silver and minor coin is taken into consideration, it will show that this mint is the largest money making institution in the Government service. As, for instance, a troy pound of copper will yield $1.20 and a troy pound of nickel $3.75. The copper and nickel cost approximately 15 cents per pound for the former and 3S cents for the latter. The tin and zinc for alloying will be added to the copper. Silver can be purchased for about 60 cents per ounce,, States is so complete that we scarcely realize there is a powerful central government to wntch over our destinies and make us comport ourselves with proper regard for the rights of citizens in our neighboring States. Frequently, an American's first real contact with Federal power comes on his return from a trip abroad, when he is advised that he must pay duty on goods that he has brought with him. He may have looked with contempt on the poor foreigner who must submit to the pettifoggery of an officious government, and he may be returning with a smug "better-than-thou" attitude, only to receive a rude shock to his complacency as the customs officials board the vessel and make him swear out a statement of his dutiable personal effects. Then, no matter if he does consider it an invasion of his rights as a freeborn American citizen, he must submit to having his trunk opened, and searched more or less perfunctorily, to make sure that he has not perjured himself. He vmay even be called aside to answer searching questions about a certain piece of jewelry. Now, how did Uncle Sam know that he had that trinket? For the first time he is aware of a spy system, not unlike that of Russia, which reaches out beyond our shores to foreign lands and keeps track of the purchases of the American tourists. Despite the humiliation of being treated as a ALL CUBAN LEAF TOBACCO MUST BE MINUTELY EXAMINED smuggler, he cannot help but feel a great respect for the omniscience of a government whose existence he barely realized up to that moment. Although examination of travelers' baggage is the most troublesome work that the Custom House has to deal with, it is a paltry business compared with the collection of duties on general merchandise. Despite the far greater attention to personal baggage, smuggling still continues among tourists, especially those of the gentler sex, who display remarkable ingenuity in concealing their dutiable goods. One customs official hopelessly admitted that "women are born smugglers, and we cannot hope ever to suppress them." As for general merchandise, the opportunities for smuggling are so remote, the co-operation between the Government and the importers themselves is so complete, and the penalty for smuggling is so severe as compared with the reward it offers, that practically no goods enter the country without paying duty. Take diamonds, for instance, which one would suppose could very readily be introduced into the country because their value per size is so enormous. Not only does the Government keep track of .purchasers of diamonds jabroad, but the, dealers do as well, and they are constantly on the lookout for smuggled stones, realizing th'a't' it is to their own interest to report any stones introduced without paying the required tariff. Furthermore, to make it unprofitable to smuggle the stones into the country, the tariff on them was reduced several years ago from 25 per cent to • 10 per cent. r Some idea of the enormous amount [V)f'%ork involved in keeping track of ; the goods that . enter this country may be obtained by a visit to the Appraisers' -Stores on the lower west side of New York. The building is ten stories high and takes up an entire block, while across the street is an annex of no mean size. In these buildings at least 10 per cent of everything that comes into New York from foreign ports must be examined. A sample of literally everything under the sun finds its wayv at one time or another info the Stores, and no matter what its character may Jtte, whether a fifty-karat diamond or a penny doll, it must be gravely considered and its value accurately and scientifically determined, so that the proper custom duty may be levied thereon. To handle this enormous quantity of material engages the attention of 938 men, of whom 134 are examiners. The duties of the examiner are exceedingly difficult. Each man has a certain classification, assigned to him, and he must be prepared to determine the wholesale value of any of the various articles that might turn up under that classification. He must be able to tell of just what material or materials the article was made, how much the materials were worth in the market from which they came, and just what was the value of the labor which, was expended upon it. Not only that, but he must know the market values of the materials and labor at the time of shipment. This must be determined on his own knowledge and not on the word of the shipper. He cannot depend on anyone else, but must stand on his own statement, which he must be ready to back up with incontestable evidence in case the importer carries an appeal to a higher court. He Customs Determinations must be able to detect all the tricks with which Unscrupulous manufacturers delude the ignorant public. For instance, in the textiles department, the examiner must be able to tell whether a piece of goods contains cotton,, linen, or silk, and in what proportion. Having determined this, he must know the quality of the material used in making it up. If it is of silk, he must determine whether the silk is artificial or natural. If natural, what kind of silk, and where it came from. If he is in doubt about the matter, he refers a sample to the laboratory, where six Pockets the fabric is subjected to a chemical test in order to determine accurately what its composition may be. Naturally, an examiner acquires before long such an experience as to qualify him as an expert, an experience that it is impossible to obtain anywhere else. Recently, curiosities, works of art, and antiques, over a hundred years old, have been admitted free of duty. the work of artists has an exceedingly difficult task. In many cases it is not at all easy to distinguish between spurious and genuine old masters. The- work of these examiners is of undeniable value to the country in preventing the importation of counterfeits. Similar protection against fraud is found in the case of tea. No duty is levied on tea, but all tea must be examined for purity before being admitted into the country. In the tea room of the New York Appraisers' Stores a hundred thousand samples of tea must be tested per year. One of the photographs shows the manner of testing. Each cup contains a different sample of tea identified by a number marked on the bottom of the cup, and one of the cups contains a standard sample. Which one it is the examiner does not know, for the identification of this sample also is marked on the bottom of the cup. The examiner then proceeds to arrange the cups according to the color and taste of the tea. After the grading is done the samples are thrown away and the cups turned upside down to show the identifying numbers. All the samples on one side of the standard are passed as good tea, while those on the other side are rejected. To make sure that no error has been made the test is repeated with a second set of samples. In order to detect any pigment used In the tea the leaves are mashed on a piece of white paper, and then the paper Is examined with a microscope for faint spots of coloring matter. The tests are very rigid and thorough, and the United States may pride itself on having nothing but pure tea to drink. Perhaps the most tedious work at the Stores is the testing of sugar. The tariff on sugar depends on the proportion of cane sugar the samples contain. This is determined accurately by means of a polariscope, which analyzes the light that passes through samples of the sugar syrup. In the case of sugar only samples are brought to the Stores, and as a check upon the examiner, two samples out of each barrel are given him. Each sample bears its own means of determining which two came out of the same barrel. Nevertheless, his work must be so accurate that when like samples are paired again the readings will be practically identical. alyses of various chemical products, particularly in the search for alcohols in medicines, etc. There is also a section devoted to metallurgical analyses. Obviously it would be impossible to examine every article imported into the country, and so it is the practice to bring at least ten per cent of a shipment to the Stores. If the shipment consists of but one or two cases of goods at least one case must be examined. The cases that go to the Stores are picked out at random by the examiner. He compares the contents of the case with the invoice and then investigates one of the articles under the invoice minutely in order to determine its quality. If this tallies with the specifications the case is passed. In the case of leaf tobacco, every package must be opened, in order to determine whether the leaves are good enough to be used for wrappers, which must carry a duty of one dollar and eighty-five cents per pound, or whether they are fit only for fillers, which pay thirtyfive cents duty. extreme northwest corner of the American continent, with the waves of the Arctic Ocean washing its northern and western shores, and the Pacific bounding it on the south ; only the narrow Bering Strait separates it from Siberia, while to the east lies Yukon Territory and British Columbia. About a third of its area is within the Arctic Circle. We purchased Alaska from Russia in 1867 for $7,200,000; for a long time we neglected its possibilities, and the revenue from it was small, but since 1867, and mostly within the past sixteen years, its utilized minerals, fish and furs have reached the enormous value of some $600,000,000; or more than eighty times its purchase price. • About half this return must be credited to minerals, chiefly to gold, while fisheries and furs provide the other half. Of course there have been large administration expenses, but these probably do not exceed $50,000,000. which we acquired for one and threequarters cents an acre, give her almost three times the area of France, and more than double that of Texas. This area falls into four natural divisions: the Arctic Slope region, with a maximum elevation of 3,000 feet; the Central Plateau, 3,000 to 5,000 feet; the Rocky Mountain system, entering from Yukon and stretching across the country in a northeasterly direction; and the Pacific system, including the Alaskan, St. Elias, and "Panhandle" ranges, with such peaks as Mt. Crillon, 15,900 feet, the active volcano Mt. Wrangell, 17,500 feet, Mt. St. Elias, 18,024 feet, and Mt. McKinley, towering to the height of. 20,300 feet, and taking rank as the highest on United States soil, and the thirteenth highest in the world. The greatest river system of Alaska is that of the Yukon and its tributaries, the Koyukuk and the Tanana. This system provides 3,000 miles of navigable water. The Kuskokwim, another important river, is navigable for 600 miles. There are several fine lakes, among them the 160-mile reach of Nikhkak, in the rugged Sitkan district. The climate is milder than might be expected from the high latitude. The interior, of course, presents rigorous conditions, but the coastal regions of the Pacific are beneficially affected by a warm current similar to that of the Gulf Stream. These regions have a -copious rain-fall; at Sitka the average is 80 inches, compared with 44.6 inches for New York City. The old belief that Alaska could never have any real agricultural value is disappearing. The Government experimental work, for which the main station is at Sitka, has resulted in producing at Coldfoot, 60 miles north of the Arctic Circle, 8inch cucumbers, 19-inch rhubarb, 4inch potatoes, and 8-pound cabbages. Lettuce is especially crisp and delicious, and turnips of good quality mcain a weight of 16 pounds. Along the coast, seaweed and fish guano make excellent fertilizers. Here the heavy rains prevent grain from being raised, except for forage; but in the interior, and particularly at Rampart, very satisfactory results have been obtained. Of the capital cities of the United States, 31 record as low degrees of temperature as Sitka, and 4 are colder than Valdez, while the winter of Juneau is usually milder than that of Washington, D. C. Roses, lilacs, and English ivy thrive in the neighborhood of Seward, and southeastern Alaska boasts fifty species of birds, among them the song sparrow and the hermit thrush. Juneau, the capital, with its quaint shops and its streets that terrace to the water, is picturesque and lively. It has good schools, churches, clubs, and hospitals, a library, a theater, a chamber of commerce, and newspapers. Fine lawns and well-furnished homes are not lacking, and the town is equipped with a good water supply and electric light. Some 27,000,000 acres of the Ter ritory is covered by timber — cedar, hemlock, spruce, and fir. Alaskan cedar is admirable for shipbuilding, cabinet work, and interior finish ; it is close-textured, and wonderfully durable under exacting conditions, and its odor is so suggestive of sandalwood that it has been shipped to Japan, made into ornamental sandalwood. Of the fishing industries, that of salmon is of commanding importance; the worth of the annual catch may be roughly placed at $15,000,000. In May, the "China boss" brings to the canneries a horde of Chinese, Japanese, South Americans, and Filipinos. Men, women and little children work at top speed during the canning season, twelve and fourteen hours a day and seven days a week. Fish poisoning is common. Housing conditions are unspeakably bad. In catching salmon, there are no restrictions as to method, and the trap system menaces the life of the industry. The day's catch of one fisherman, during a particularly heavy "run," was 3,000 salmon. Natives are asking for remedial legislation, the enforcement of the laws governing restraint of trade, and the regulation of child labor. Another urgent need of Alaska is more lighthouses along her dangerous coasts. pointed by the President for a fouryear term. Since 1912 it has had a Legislature of two Houses. The Territory is in the Ninth Circuit of the Supreme Court, with its four judicial divisions at Juneau, Fairbanks, Valdez, and Nome. Each division elects two members for the Senate and four for the House, the Senate thus consisting of eight members and the House of sixteen. One delegate is sent to Congress from the Territory. Business licenses furnish most of the revenue, which is approximately $1,000,000. In 1909 there were 152 industrial establishments, with a combined capital of $13,000,000, a combined output valued at $11,130,000, and employing 73,479 men. Education is carried on by means of a hundred schools, enrolling, in 1913, 6,563 children, and costing $350,000 to support. These are In 1913, 460 miles of railroad were in operation. In 1915, two routes for a most important Government railroad were before President Wilson. One was the Cordova-Fairbanks route; the other was that from Seward, on Resurrection Bay, to Fairbanks, 471 miles inland along the Tanana River. He finally selected the latter route, two reasons probably influencing his choice. First, a railroad from Seward almost to Knik already exists, and was purchasable for the very reasonable sum of $1,150,000; this reduces the length of the new work by some hundred miles. Second, Seward has probably the best harbor and town site in Alaska. The new road will cost $26,000,000, including the construction of a branch from Matanuska Junction to the Matanuska coal field, one of the most valuable fields of high-grade coal in the Territory. The work is under the direction of the Alaskan Engineering Commission, and will later be exended to Yukon, thus opening up the interior and its vast resources. According to the census of 1910, the population of Alaska was made up of 36,347 white and 28,009 natives, Asiatics, and negroes. The natives are the Eskimo, or Innuit, of the north and northeast, the Tinnehs, or Indians of the interior, the Aleuts, or islanders, and the Tlingits of the North Pacific coast. was formerly known as the Sandwich Islands, and is found in the North Pacific Ocean. Hawaii, the largest and most southerly of the group, emerges from the sea about 1,300 miles north of the equator, and 2,200 miles from San Francisco. The discovery of these islands is usually credited to Capt. Cook, in 1778, although an earlier discovery is claimed by Spain. American missionaries were sent there in 1820, and these men reduced the language to written form ; soon after this idolatry was abolished by a decree of the ruler, Kamehameha II. In 1844, the independence of the islands was guaranteed by the United States, Great Britain, and France. On August 12th, 1898, the archipelago was transferred to the Government of the United States, and on June 14th, 1900, it was organized as a Territory. The islands have an area of 6,449 square miles. Although they lie entirely within the tropics, the heat is moderated by the trade winds that blow for nine months of the year; clear skies and an equable temperature characterize the climate and conduce to the healthfuv conditions which prevail. The temperature at Honolulu, the capital, averages 71 deg. F. in December, and less than 77 deg. F. in July. The rainfall varies greatly, the windward side of the islands receiving the most. At Hilo it may be eighty inches or more, while at the more sheltered Honolulu the average is probably within thirty-eight inches annually. There are no hurricanes of damaging violence, although several high gales may be expected in the course of the winter season. waiian group, besides numerous islets for the most part uninhabited. Hawaii Island, the largest, contains 4,210 square miles, and the population in 1910 was 55,382. Here Mauna Loa, the largest volcano in the world, looms 13,675 feet into the air; Mauna Kea slightly exceeds this height, reaching 13,805 feet, and ranking as the highest peak in the Pacific Ocean. Mauna Loa is still active, and sixteen miles away, in a southerly direction, is Kilauea Hill, which has the distinction of possessing the largest active crater in the world, nine miles in circumference, with vertical sides 1.000 feet in depth. The eastern coast is scarred streams pour their waters. Northeast of Hawaii is Maul Island, of 728 square miles, with a population in IS/1.0 of 28,623. It is mountainous, and presents some picturesque scenery. Its two main portions are connected by a sandy isthmus that is but little above sea level. The summit of Mount Haleakala (10,032 feet) may be reached on horseback; the long, regular gradients make this feat comparatively easy. At the summit is found the largest extinct crater in the world. The northwest coast possesses a good harbor in Lahaina, with steamers plying between that port and Honolulu. Molokai Island, not much more than a third as large as Maui, Is occupied by a low mountain range, and is popularly known as the site of the leper settlement, where all those affected by the disease are isolated. Oahu Island, with a population of 90,000 and an area of about 500 square miles, presents some of the most charming, natural formations, combining mountains and ravines, cascading waters, and rich foliage and vegetation into pictures wholly satisfying to the artistic eye. Coral reefs girdle its coasts, and on the southern shore is Honolulu, the capital of the Territory, on a plain formed by the upheaval of. an old coral reef. Kauai Island possesses the most fertile soil of any in the group, the advanced decomposition of its lavas showing that volcanic action has been long extinct. It is roughly circular in shape, of an area of 547 square miles, and in 1910 the population was 23,744. Twenty miles to the southwest is the little island of Niihau. towns. The windward districts are quite heavily forested. Sandalwood is no longer obtainable, but the candle-nut and the screw pine are characteristic of the slopes and valleys, while the cocoanut palm grows freely on the coast. The soil is generally very productive, and in 1910 there were 4,350 farms, covering 2,590,600 acres, the land being valued at $78,000,000; the live stock upon them was worth $4,300,000. The commercial products include coffee, rice, arrowroot, honey, bananas, sisal, wool, hides, skins and tallow, rubber, cotton, and tobacco, but sugar and tropical fruits are the chief exports. On the sugar plantations the growing use of irrigation canals is resulting in increased crops ; that of 1914 was 618,000 tons, and the yield is from two to seven tons to the acre, depending upon location. The industrial establishments of the islands numbered, in 1910, 500, with 7,572 employees, and a combined capital of $23,875,000; the material used was valued at $25,629,000, the output at $47,404,000. Communication facilities are constantly being improved. There is a large and increasing mileage of good roads, and more than 300 miles of railway, 240 miles of it being on the islands of Hawaii and Oahu. In Honolulu almost every house has its telephone; there are 6,000 miles of wire on the five main islands. The best harbors, after that of Honolulu, are Pearl, on Oahu ; Hilo, on Hawaii; and Kahului, on Maui. From these and the lesser ports of the group, 436 vessels of a total tonnage of 1,574,845 cleared in 1915, and in the same year 456 vessels, of 1,605,925 tons, entered. Inter-island transportation is provided for by a fleet of sixteen small steamers. At Honolulu new wharves have been constructed, and the largest steamers can now be accommo- the harbor of Kahului has been deepened. The erection of lighthouses has progressed steadily. Ten steamship lines touch at the islands, from Canada, the United States," the Philippines, China, Japan, and Australia. Wireless puts the islands into communication with each other, with the Pacific coast, and with vessels at sea, and cables stretch to both shores of the Pacific. Upon formal annexation to the United States, a Legislature of two houses was established. Fifteen members are elected for a four-year term to the Senate, and thirty members with two-year terms constitute the House of Representatives. Once in two years these bodies meet in a sixty-day session. The President of the United States appoints for four years a Governor, at a salary of $7.000, and a Secretary. A Delegate is elected to the United States Congress by popular vote. The judiciary consists of a Supreme Court and Circuit and District Courts ; district magistrates are appointed by the Chief Justice of the Supreme Court; all other judges, including those of a United States District Court, are appointed by the President. There were nearly 8,000 convictions in 1915, mostly for minor offenses. There were 170 public schools in 1915, where 735 teachers gave instruction to 29.000 pupils, at a cost of $772,000; besides this, $70,000 was expended upon new buildings. These are free schools, and English is the language in general use. In addition, there are about fifty private schools, with an enrollment of 7,700 pupils, industrial schools for both boys and girls, a normal school, a College of Agriculture and the Mechanic Arts, and a reformatory. The enrollment records disclose the fact that of all these pupils some 18,000 are Asiatics, 8,000 are of Hawaiian blood, 5,700 are Portuguese, and 1,403 American, the re- In. the old days, the Hawaiian was a cqast dweller, having his grass hut under the palms, and his garden or small plantation on the hill slopes. He was a great fisherman, and there are in existence lines made from fine olona fiber which have seen a century of service, and are still in good condition. His huge sailing canoe was a familiar sight to the Mtlanesians, and the impression made by his gigantic war canoe, carrying pean costume ; his fishing line, when he condescends to fish, is of cheap foreign manufacture, and much of the fish he eats comes from the tin can ; the picturesque hut of grass has been almost wholly replaced by the shack of rude wood, and he is on intimate terms with the slum of the town. When Capt. Cook found him, he was one of a proud race 400.000 strong ; to-day that raoe has dwindled to less than 25,000, if we exclude the 12,000 of mixed GOVERNMENT BUILDING, HONOLULU its hundred ruddy-skinned warriors, must have been awe-inspiring. This was in the days when the goddess Pele spoke from her volcanic throne, and "Pele's hair," a sort of natural mineral wool spun by the wind from lava-drops, was found in the crevices as substantial evidence of her reality. All this has passed. The Hawaiian of to-day affects Euro- acteristics that make him so attractive to us. He is still a fine specimen of physical humanity, pleasureloving, athletic, and musical in voice and in temperament. His guitar still holds tones that have never been duplicated upon other instruments or evoked by other fingers. His women continue to weave their flower garlands and bright none of its abandon. There are in the islands 80,000 Japanese, 22,000 Chinese, and 22,000 Portuguese, and several thousand Filipinos have been introduced. Japanese, Chinese, and Korean immigration is now forbidden. The census of 1910 gives the population of Honolulu as 52,183, and the entire population of the inhabited islands is now estimated to be 322,856. Honolulu is in many aspects quite modern ; electricity lights its streets and operates its cars. It has a Roman Catholic and an Anglican bishop, and ministers of several other denominations. It has fine parks, a water system, hotels, clubs, newspapers, a hospital, a large library, a museum, and several tary works are in progress at various places in Oahu, including fortifications, a naval station, and a drydock at Pearl, on the island of Oahu. augmented by licenses and land sales, road, school and poll taxes. The assessed value of all property in 1915 was $176,601,222, the annual receipts from all sources were $2,796,146, and the expenditures $2,747,270; there is a bonded debt of $7,873,000. The exports of the Territory were $62,464,759, the imports $26,416,031, for the year ending June 30th, 1915. Practically all the export trade was with the United States, as was 80 per cent of the import trade. Raw sugar accounted for $51,368,995 of the export figures, refined sugar for $1,584400, and tropical fruits for $6,319,129. PHILIPPINE ISLANDS, 1899 IN our East India possessions, the Philippine and Sulu Islands, we have a territory as large as the United Kingdom, with a population larger than that of Canada. To put it more exactly, if less impressively, the area of the archipelago is 121,400 square miles, and the population is 9,000,000. The formation of the group suggests a wish-bone, with the largest and most northerly' island, Luzon, as the stem ; Mindoro and the long, narrow Palawan, with the chain of islets between them, forms the western fork of the bone; the eastern fork is made up of Samar, Panay, Negros and Mindanao, the latter being the second largest and the most southerly island of the group. The islands and islets number altogether 3,141. The China Sea, which washes the western coasts, puts 500 miles of water between the group and the continent of Asia. The Sulu chain bridges the gap between Mindanao and Borneo, and bridged by the long arm of Palawan and Balabac; these extensions enclose the Sulu Sea ; to the south rolls the Celebes Sea, and on the east is the vast extent of the Pacific, the first mainland encountered in this direction being Central America. The Philippines were discovered by Magellan in 1521. Spain took them by conquest in 1542, and held them for more than three centuries \ but on the outbreak of the SpanishAmerican War, Admiral Dewey, ritt in the following August. The Mt. Mayon, in Luzon, broke into devastating activity; mild earthquake shocks are frequent, but the buildings are so constructed as to withstand fairly severe shocks. The islands are all mountainous, the general trend of the systems being north and south. Mt. Apo (10,300 feet) on Mindanao is the highest summit ; no other peaks exceed 9,000 feet. The longest river is the Cagayan, LOVELY PHILIPPINE SCENERY Treaty of Paris (December 10, 1898) ceded the archipelago to the United States. Then followed battles with the native forces under Aguinaldo, ending with his capture in March, 1901. Of volcanic formation, the Philippines still have twelve active volcanoes. In 1880 destructive earthquakes were experienced ; in 1897 which rises in the mountains of the eastern coast of Luzon and traverses the island in a northerly direction for 220 miles; other important Agusan in Mindanao. The Laguna de Bay, a fresh water lake, near Manila, is thirty miles long, and numerous smaller lakes are scattered throughout the islands. The archi- pelago has a longitudinal extent of a thousand miles; from northern Luzon to southern Mindanao is as far as from New York City to southern Florida ; hence it is to be expected that climatic conditions vary greatly in different portions of the group. While the climate is, of course, tropical, the heat is on the whole more bearable than that encountered in many temperate countries. The seasons may be designated as hot, wet and cold. The hot season (March to June) is at its worst just before the southerly trade winds begin to blow ; in the latter part of this season violent thunderstorms occur ; from July and through October the rain falls in torrents, often registering seventy inches for the four months ; in Manila, seventyfive inches is perhaps a fair annual average. From November to March is the so-called cold season, when heavier garments are necessary to comfort and a sense of invigoration is born of the cloudless skies and the cleansed air. The mean temperature at Manila is, for the hot season, about 87 degrees; for the wet season, 85 degrees, and for the cold. 72 degrees. The fauna of the islands is not prodigal in mammals, but it offers peculiarities that well repay the naturalist. There are wild boar and deer; monkeys are found everywhere, one species being a pure white; there is a lemur about the size of a squirrel, which sleeps the day through and seeks its food by night, its long hind-legs propelling it over the ground in frog-like leaps ; there are two species of civet, and a wild cat ; also porcupines, squirrels and rats, and numerous species of bats; lizards, alligators and turtles are found, and some enormous molluscs : the shell of the tablobo has been known to attain the weight of two hundred pounds. The waters provide both curious and valuable fish. The usual domestic animals are met with, and the buffalo is used in the fields. The forested area is extensive, and is under the supervision of the United States Forestry Bureau. It offers a wonderful variety of timber, cabinet woods, palms, trees yielding gums, spices and dyewoods, and bamboo. No matter what particular quality or combination of qualities may be sought to meet special uses, a timber may readily be found that will admirably serve the purpose. Since the supply greatly exceeds any local demand that is likely to arise, these forests constitute a most valuable resource. Three-fourths of the trees are of the dipterocarp family, corresponding to the conifers of our zone. From this family may be obtained an abundance of woods eminently suitable for interior finish and for furniture, and exhibiting a wide range of color and texture. Tanguile and red lauan closely resemble mahogany in appearance. If hardness be the quality sought, guipo and apitong may be relied upon ; they are extensively used for flooring, and a still harder wood used for this purpose is yacal ; this latter is ideal for heavy construction work, as are also ipil and pagatpat ; these timbers make strong and durable railroad ties. Should we seek beautiful cabinet woods there are many trees of the locust family, among which may be found colors and grainings to satisfy the most exacting tastes; the ipel is a striking example in this class." Then there are woods that lend themselves to less common and even more difficult demands. Mancono and dungon make the finest dumb-bells, bowling balls and bearings. Calantas is an excellent substitute for the Spanish cedar used in cigar boxes. Ebony, the highest priced of all Philippine woods, has a wide distribution, but the trees do not attain any great size; perfect pieces bring $300 a thousand feet board measure. The islands are far from poor in minerals. In most of the larger ones gold is found, and the crude workings of the natives have now given place to an established industry that, in 1913, produced nearly a million dollars' worth of the precious metal. Other minerals found in greater or less quantities are silver, platinum, mercury, lead and manganese ; there are several coal fields, iron exists in various parts of the archipelago, copper has long been mined by the natives for manufacture into utensils, and there are evidences of sulphur, petroleum, rock salt, kaolin and gypsum. In 1913 the value of all minerals yielded up by the soil was $1,972,290. The aborigines were probably Negritos, who were gradually forced into the remoter natural strongholds by their Malayan invaders, until the latter came to dominate the islands. Of the present entire population of 9,000,000 nearly S,000,000 are Roman Catholics; the Moros are Mohammedans, and number perhaps 300,000; the uncivilized, pagan tribes of the mountains, scattered throughout the islands, make up the remainder. It will be seen that the non-Christian and uncivilized elements can neither singly nor together be taken as in any way representative of the Filipino people. The Malayan is the dominant and representative stock. At the social functions of Manila one meets highly educated men and dress. Should we engage one of these men in conversation about his country, he will tell us that writing was common before the arrival of the first Spanish monk, and that the inhabitants were a highly moral people at that time; that they have enjoyed three centuries of civilization ; that at the time of the American occupation, 45 per cent of the Christians were literate ; that there was a university in the Philippines before Harvard was founded, and that the Americans found on their coming 1,674 public1 schools, and colleges for both men and women in every capital city of any importance; that Luna had already achieved international fame as an artist, and music and poetry of a high order were written ; and that the unusually fine examples of wood-carving demonstrate the artistry of the Filipino craftsman. On the other hand, he would not deny that American occupation had increased the number of public schools to more than 4,000, and had raised the literacy to 75 per cent. There are now 37 educational divisions under direction of the Secretary of Public Instruction, with a public school enrollment of 500,000; there are noi-mal and industrial trade schools, and private MANILA schools enroll some 10,000 pupils. The University of the Philippines, maintained by the State, has colleges of Liberal Arts, Law, Medicine and Surgery, Engineering, Fine Arts, Veterinary Medicine and Agriculture, with 2,000 students. Much thought has been given to the solution of the problem presented by the Moros. With this in view, a hundred miles of Moro country in the island of Mindanao has b'eeu organized into eight colonies, where the mixed peoples live peacefully together, their children attending the same schools. English is now the official language of the archipelago. The educated Filipino speaks several languages and follows American politics assiduously. The people are in general, kind, hospitable and intelligent. Agriculture is the chief industry, in which one-half the workers are engaged. More than 8,000,000 acres are under cultivation, 3,000,000 acres being devoted to rice. The principal products are rice, Manila hemp, copra, sugar, maize and tobacco. Obsolete methods and insufficient labor account for the agricultural possibilities being in a neglected state, but our occupation is already accomplishing good results in this direction. All public schools have now an elementary course in agriculture, and a rural credit system is fur- NATIVES OF JOLO SELLING FRUIT thered by an Agricultural Bank having twenty-six agencies. In 1914 the outstanding loans of this institution aggregated nearly two millions of dollars. The 1915 imports amounted to $44,479,861, the exports to $50,915,061. Abaca or Manila hemp stands first on the export list with a value of $19,000,000; copra next with a value of $12,000,000, and sugar third with a value of $9,712,757; cigars and cigarettes accounted for $2,102,317, and all other tobacco for $1,589,678. The value of the chief imports was: Cotton goods, $9,669,247; rice, $5,448,301 ; steel and iron products, $3,993,984. Half the entire trade of the islands is with the United States. The central government is vested in a Governor-General, who is also President of the Philippine Commission, assisted by eight commissioners, four of whom are the executive heads of departments known as Interior, Commerce and Police, Finance and Justice, and Public Instruction. The commission constitutes one house of the legislature, the other is known as the Assembly, with eighty-one members elected by limited franchise for four years. Two Resident Commissioners, elected by the Legislature, take their seats, but without a vote, in the United States House of Representatives. Politically, the archipelago is divided into thirty-six provinces and, in addition, the Department of Mindanao and Sulu, which is itself divided into provinces and districts. Thirty-one are known as regular, and the others a s special, provinces ; the first class are governed by provincial boards elected by the people; governors of the special provinces are appointed by the Governor-General arid the commission, acting in concert. Municipal officers are elected for terms of four years by the voters; about nine hundred towns enjoy this autonomy. Each town has a justice of the peace ; in each of the twenty-six judicial divisions the administration of justice is under a judge of first instance, with the exception of the city of Manila, which constitutes the ninth district or division, and to which four judges are assigned. There is also a supreme court. Besides the municipal police, there is what is known as the Philippines Constabulary, with a strength of about 350 officers and 5,000 men. The garrison of the islands has 10,000 American and 5,000 native troops, and a body known as the Philippine scouts number about 5,000. Customs duties and internal taxes provide most of the revenue, which, in 1914, was $11,912,761 ; in the same year the expenditures were $13,333,321, but as at the beginning of the year there was a balance of $5,679,587, there was still on hand at its conclusion $4,259,027. In 1914 the bonded debt was $16,125,000. Of the expenditures for this year, more than $5,000,000 was devoted to social and public improvement and economic development. Leprosy, smallpox, the bubonic plague and cholera were formerly prevalent in the islands. Radical measures have been taken to stamp out these diseases, and much progress has been made. There are between two and three thousand lepers isolated in a colony on the island of Culion. Intestinal diseases, which ravaged the Philippines, have been reduced by almost one-half; this result is attributed largely to the pure water supply secured for Manila ; in the smaller towns this has been accomplished by the drilling of hundreds of artesian wells. It is as yet hard to obtain accurate health statistics except for Manila; here the birth rate is about 36, and the death rate 25 or less, per thousand. Manila has a population of 270,000; of these 17,000 are Chinese; there are probably 6,000 Americans, counting in the garrison, and 6,000 Europeans, two-thirds of them Spaniards. Chinese immigration to the Philippines was prohibited in 1902, and registration is required of Chinese laborers. Th£ number of Chinese now on the islands is put at 50,000, and the entire number of whites (American and European) is estimated to be 20,000. The savage tribes of the mountains differ widely in many respects, and it is a mistake to call them all "Igorrotes." Even the Igorrotes, filthy and barbarous as they are, possess some good traits. Although they live in mountainous parts of the country they cultivate the soil industriously, first terracing the slopes, then laying out their plots upon these terraces, irrigating them by canals that are constructed with no mean skill. They are monogamists among whom di- fidelity is severely punished. There is little manufacturing done in the Philippines, but pina fibers, cotton and silk are woven into fabrics that are frequently attractive and durable; baskets, cordage, pottery, furniture, hats, mats, musical instruments and carriages are also made; but the only manufacturing industry of note is that of cigars and cigarettes; 305,000,000 cigars were made on the islands in 1913, about one-third of this output being consumed in the country while the rest was exported ; and in the same year 4,500,000,000 cigarettes were produced, mostly for local consumption. There are more than 5,000 miles of good road in the Philippines, 1,800 miles being hard-surfaced road of the first quality ; permanent bridges and culverts number nearly 6,000. At the time of the American occupation in 1898 there were but 120 miles of railway ; this connected Manila with Dagupan. There are now 720 miles, with 212 miles more planned, if not actually under construction ; 600 miles are on Luzon, 72 on Panay, and 60 on Cebu. The islands have 5,300 miles of telegraph lines and 1,173 miles of cables; 700 post-offices handle the mail. The postal revenue for 1914 was $380,942, and the telegraph revenue was $283,305. Money orders were sold to the value of $8,272,858. The fine harbor at Manila will allow of the entrance of vessels drawing thirty feet of water, and next in importance are the harbors of Cebu and Iloilo. Cebu is a city of 60,000 population, and Iloilo has 50,000. The ports of the Philippines in 1914 received foreign vessels to a tonnage of 1,912,756, and the tonnage of foreign vessels clearing was 1,931,249. The mercantile marine consists of some 700 vessels, about one-fourth of this fleet being steam vessels, totaling 55,000 tons. Four banks are established in the Philippines. In 1904, after a troublesome experience with the Mexican dollar, the United States tried the expedient of guaranteeing by gold the Filipino peso, a coin worth fifty cents in American money. Fluctuations in value are thus avoided, and the experiment has proved quite successful. The postal savings bank has now about 45,000 depositors, and the total deposits are nearly 3,000,000 pesos. The alertness of the Filipino, and his eagerness to learn, have already been touched upon. It should not, then, surprise us that more than a hundred newspapers are published on Filipino soil. The predominating language of the press is Spanish, but no less than 27 of these newspapers are in English, 33 are in native dia- PHILIPPINE COFFEE PLANTATION lects, and 3 are in Chinese. If further promise of a Filipino renascency is required, we may find it in the quiet tribute of the Hon. John Barrett, director-general of the PanAmerican Union, who, in favorably comparing the Philippine Congress with the Japanese Parliament, finds in it "a ministry of bright men, of acknowledged ability as international lawyers." tilles, in the West Indies ; it was discovered by Columbus in 1493, and was held by Spain until its capture by the United States in 1898. It is 100 miles long and about 40 miles in width, except toward the eastern end, which narrows considerably ; the area is 3,436 square miles, and it has, besides, several islands of importance, of which the largest is Vieques (100 square miles). Porto Rico is 1,400 miles from New York and less than 1,000 from Colon, Panama. It is wonderfully fertile and presents a beautiful appearance. mum height of 3,800 feet, traverses the island from west to east, and there are 1,300 streams, of which fifty may be termed rivers ; but none are navigable for more than a mile or two from the coast. The hilly nature of the country causes tht trade winds to precipitate their moisture upon the northeastern lowlands, where the average rainfall is 120 inches, while at San Juan, the capital, it is but 55 inches. The temperature varies between 50 degrees and 100 degrees. Although there are 40,000 small farms, valued in 1910 at more than $102,000,000, and 60 per cent of the workers are on the soil, not much more than one fourth of the land is under cultivation. The lowlands produce sugar, the hill slopes coffee and tobacco; much of the latter, of superior quality, is grown under cloth. Other products are sea island cotton, textile fibers, Indian corn, sweet potatoes, rice, maize, plantains and yams. Grapefruit, oranges, pineapples, cocoanuts and other tropical fruits flourish. Most of the trade is with the United States. The country south of the mountain range is not so well watered, but for this district there is now under construction an irrigation system, to cost $3,000,000, which will greatly increase the output of the island. Molasses and honey are products of importance, but the staples are sugar and coffee, the former constituting 47 per cent of all exported products. In 1914 320,633 tons of sugar, valued at $20,240,335, and 50,211,947 pounds of coffee, valued at $8,193,544, were shipped from Porto Rico. Indian sandalwood and mahogany are all found on the island, and the Talauma, with its white, sweetscented flowers, furnishes a timber locally known as "sabino." At least twelve different plants are used in dyeing and tanning, and the fruit of the vijao, which grows in wild luxuriance, is used by the natives for ink and dyes, which are claimed to be quite fast in color; the root of the turmeric also yields a dye used for hammocks, ribbons and commercial possibilities. Porto Rico is poor in fauna ; the passing of the armadillo and the agouti has left only small rodents, squirrels and a species of great land turtle as representative of the four-footed population. Of the few reptiles, none are venomous. Doves and various song birds frequent the higher districts; green parrots abound in the forests; and water birds, among them the gaudy flamingo, are found along the coasts. Both salt-water and fresh-water fish are caught in considerable quantities. Of the domestic animals, cattle are raised in sufficient numbers to form an industry worthy of note. Little is known of the extent ol the mineral resources. Since much alluvial gold was recovered by the Spaniards, it is reasonable to infer that rich veins await discovery in the mountains. Copper, iron, tin, bismuth, mercury, platinum, nickel and coal have been found, and salt is worked extensively. This latter is the only mining enterprise upon an established basis. under way are completed the entrance will be 600 yards wide, with 30 feet of water. The city had in 1910 a population of 50,000, with a town hall, a cathedral, a general hospital and a theater. Other towns are Ponce, which had 63,444 population, and Mayaguez, with a population of 42,429. The island boasts 74 municipalities, each electing its own mayor, city council and city officials. Porto Rico is administered by a Governor and an Executive Council, appointed by the President for a four year term ; six heads of departments and five natives make up the Council. The Legislative Assembly is composed of two bodies, the Executive Council and a House of Delegates; the seven electoral districts each supply five members to the House of Delegates. A Resident Commissioner to the United States is also elected by popular vote for the term of two years ; he takes his seat in the Federal Congress. Enactments of the Council and the House are subject to the veto of the Governor. The judiciary of the island includes an Attorney General with his staff, a United States Court, and a Supreme Court of five, all appointed by the President; the Governor appoints fifty-nine justices of the peace ; seven District Judges are appointed by the Governor, while the people elect to office the judges and officials of thirty-four municipal courts. took charge of affairs. In 1899 more than 83 per cent of the people could neither read nor write. That year saw the complete reorganization of the school system, education being made compulsory. The number of common schools has been increased from less than 800 to more than 4,300, with an enrollment of 207,010 in 1914. There are four high and twenty-five continuation schools, besides night schools, kindergartens and private schools. At Rio Piedras, a few miles from San Juan, is situated the University of Porto Rico, where students of both sexes receive instruction in such special subjects as teaching, scienca, engineering, medicine, law, architecture and agriculture; the farm and dairy of the University enable students to master the practice as well as the theory of agriculture, and in this the Government experiment station at Mayaguez offers its wholehearted and valuable co-operation. In 1892 the island possessed 119 miles of railway. It now has more than 220 miles. This links together the towns of the western coast, partly encircles the island, and to a certain extent opens up the interior. It is intended to extend the present facilities until there is a railroad entirely around the island, and another project is the running of a new line across the island, with many branches and ramifications. There are a thousand miles' of tolerable roads in Porto Rico, 600 miles or postal telegraph wire, government owned, forty telegraph stations and 80 post offices. The telephone is also winning its way into business and social demand. The population was estimated for 1914 at 1,184.489. an increase over 1910 of 66,477. Almost nothing is known of the original inhabitants ; a few of their stone weapons, implements and images, with some a number of mystifying designs. The revenues of Porto Rico come from customs and excise, from the tax on property, an inheritance tax FIRST FLAG RAISING IN PORTO RICO and various fees and licenses. The receipts from these sources for the year ending July 1st, 1914, were $10,108,708; the property had an assessed value of $179,271,023. The police force numbered about 700 men and the military forces about 600. The industries of Porto Rico are chiefly concerned with the production of embroideries, drawn work and hats. In 1910 there were 939 industrial establishments; their combined capital was placed at $25,544,385, and their output at $36,749.742. These establishments employed 15.582 work people. The tonnage of American and foreign vessels clearing from Porto Rican ports during the year ending July 1st, 1914, was 1.216,909. The island is a port of call for thirteen steamship lines. In 1914 the imports were valued at $36.406.787 and the exports at $43,102,762. In 1915 the exports to the United States alone reached a value of $43,311,920. GUAM, the largest and most southerly island of the Ladrone group, the rest of which belongs to Germany, lies in the North Pacific Ocean, nearly 1,500 miles east of the Philippines. It was discovered by Magellan in 1521, was held by Spain from 1688 to 1898, and was captured by the U. S. cruiser "Charleston" during our war with Spain. The island is 29 miles long, from 3 to 10 miles in width, and its area is 210 square miles. The northern part presents the appearance of a large plateau, while the southern portion is hilly, attaining a height of 1,280 feet. The vegetation is luxuriant, and soil and climate are admirably suited to agriculture, but the laziness of the natives has prevented any extensive development of this pursuit. October to May is the dry season, although rain not infrequently falls. The temperature is even, with August and September the hottest months, the yearly mean temperature being about 81 deg. Fahr. Guam is occasionally visited by devastating typhoons and earthquake shocks are not uncommon. Trade The valleys are forestrated with valuable hardwoods. Food fruits are the custard apple and sour sop, the pineapple and the cocoanut ; breadfruit and bananas grow freely. The hau produces very strong and durable rope ; the leaves of the pandanus are used in braiding hats and mats ; the ylang-ylang is well known for the perfume it yields. Among the vegetable products are rice, maize, sugar, cotton, indigo, castor oil and tobacco. About the only native animals are small rodents, but the roe and the wild goat thrive, as do swine and oxen. There are no venomous pedes are not dangerous. The population of Guam is estimated at 13,000; the inhabitants are for the most part Chamorros with a mixture of Tagal, Malay and Spanish blood, speaking a Malay-Spanish dialect, but English is rapidly gaining ground. The American occupation is raising native standards. The lepers have been segregated, telegraphic communication has been improved, public schools established and a good hospital maintained. There is a Government agricultural experiment station at Agana, the capital, which has paved streets, sewers and a water system and is connected with Apra, the only safe harbor, by a very good road. The commandant of -the naval station acts as Governor. The island has four administrative districts, each with a commissioner as its executive head. Peonage has been abolished and courts of justice established. The 1914 imports were valued at .$160,000 and the exports at $50,000. Guam is a port of transit between the United States and the Philippines and army transports call there at frequent intervals, sometimes monthly. THE Samoan group is found in the South Pacific Ocean, 420 miles northeast of the Fiji Islands; named by Bougainville "lies des Navigateurs," from the natives' skill in handling their canoes, it still appears on many maps as Navigators' Islands. The whole group numbers thirteen islands, for the most part mere rocky and barren islets. By the Tripartite Treaty of 1899, all those east of 171 deg. long, were turned over to the United States, which has had a naval and coaling station there since 1872. Germany retained possession of that portion of the group lying to the west of this meridian. The United States possessions comprise Tutuila, with an area of 77 square miles and a population of 7,300; Ofu, Aunua and Olosenga, having together an area of some 25 square miles with about 2,000 population; and Rose Island, uninhabited. Pagopago, the capital of American Samoa, is on the south coast of Tutuila ; its fine harbor almost divides the island into two parts. Tutuila is the best island of the entire group, of a mountainous character, but possessing extensive forests. The natives of the archipelago are forbidden to sell land to the whites, but are permitted to retain their own laws and customs in so far as these do not conflict with the laws and ordinances established by the Governor, who is also the naval commandant. He is authorized to appoint officers, regulate the police and make ordinances dealing with such matters as the assessment of taxes and the importation of spirits. A body of seventy-five men, under a drill sergeant of the United States Navy, constitutes a native guard. The natives are of fine physique, but are indolent and very independent, and the plantations have to be worked by imported labor. Hookworm and the yaws are prevalent, but a great deal has been done toward the amelioration of these diseases, and much attention is paid to sanitation and the public health. besides these, there is one government supported school and another largely maintained by the native population. The total number of schools is 83, with 2,000 pupils of both sexes. The political divisions are three — the Eastern, comprising eastern Tutuila and Aunua ; the Western, which is western Tutuila ; and the District of Manua, taking in Tau and its neighboring islets. Each district has its native Governor ; under him are the county chiefs, and under them the chiefs of villages. Each village has its own court. The products of American Samoa include cocoanuts, cocoa beans, bananas, breadfruit, pineapples, oranges, yams and taro, the last being a plant with leaves similar to those of the water-lily, with roots that are baked and used as food. Some cotton, maize, sugar and coffee are raised for local consumption. Copra (dried cocoanuts) and cocoa beans are about the only things exported, the output of copra running to 1,500 tons per annum ; this product is largely used as legal payment for taxes. prising 436 square miles of territory, was acquired by purchase, February 26, 1904, the sum of $10,000,000 being paid to the Republic of Panama. In addition, Panama is to receive an annual payment of $250,000 during the life of the treaty, beginning nine years after date of ratification. three marine miles from mean low water mark in each ocean and extends five miles on each side of the center line of the route of the canal. It includes the group of islands in the Bay of Panama, named Perico, Naos, Culebra and Flamenco. The cities of Panama and Colon are excluded from the Zone, but the United States has the right to enforce sanitary ordinances and maintain public order there, in case the Republic of Panama should not be able to do so. FIRST PART BY THE EDITOR FROM the earliest time the flag has been of prime importance. According to Livy the cavalry flag was a square piece of textile material fixed to the cross bar at the end of a spear. The Roman standards were guarded BLACK AND WHITE with the greatest care and veneration, and were kept in the temples of the great cities, and after the advent of Christianity churches received them. All through mediaeval various names, which, like the "Oriflamme?' of France, have come down to us as a valuable heritage. Disregarding the history of flags in general we come to our flag, which is a modern flag in every sense of the word ; it has no myths or legends connected with it, and the Heralds' College has never been invoked in -its design. Its bright colors are attractive and can be seen long distances, which is not the case with all flags. Love for the flag has been fostered by State, school and church, so that nothing is more venerated In this country than the "Stars and Stripes." Great care has been taken by the Federal and State governments to give the greatest possible protection for the national emblem ; thirty-four States have legislation to preserve the American Flag from desecration, mutilation or improper use. The national flag must not be used for advertising, as a cover for a magazine, and the statutes of the United States forbid the use of the flag as a trade mark. The settlements in the thirteen original States were largely English, and the ceremonial flags of the colonies took the form of the English national standard of the period. In 1643 the colonies of Plymouth, Massachusetts Bay, Connecticut and New Haven formed an alliance called the "United Colonies of New England," and in 1686 they adopted the cross of St. George with a gilt crown over the monogram of James II. NEW ENGLAND COLORS, As early as 1700 the colonies began to use flags of their own design, the "pine tree" flag of New England being an example. There are various forms of this flag. In one in- cross of St. George in the center and a pine tree in the first quarter. This flag may have been used at the battle of Bunker Hill. Another variation was a flag with a white ground and a green pine tree in the center. The rattlesnake was another favorite symbol in the Southern colonies, and there are many variations of this flag, but the head of the snake must CAROLINA always face the staff. The motto is usually "Don't tread on me." South Carolina had a yellow flag with the snake on it. An early flag displayed in the South was a dark blue flag with a white crescent, and was raised at Charleston, S. C., on September 13, 1775. The word "Liberty" was a Harbor, June, 1776. These flags, so interesting to students of colonial history, were not, however, strictly speaking, the forerunners of the "Stars and Stripes." The flag, as we have it to-day, is the result of an evolution. The most prominent features of the flag are COMPANY .the bars. These are not original, however, as we find them in the flag of the Dutch West India Company, and in 1704 the ships of the English East India Company carried flags with thirteen red and white stripes and the cross of St. George in the canton. It has also been suggested that the arms of Washington may have suggested the original form of our flag, but there seems nothing to substantiate it. The first known instance of the use of stripes was in the flag of the Philadelphia Troop of Light Horse, 1775. This may have been suggested by the "Cambridge Flag," which Washington raised at Cambridge on January 2, 1776. This was truly the first American flag to show in concrete form the union of the colonies. There were thirteen alternate stripes of red and white, and in the canton was the combined crosses of St. George and St. Andrew. It is variously called the "Grand Union Flag," the "Great Union Flag," and the "Union Flag." The name "Cam- RAISED AT CAMBRIDGE JAN. 2, 1776 bridge Flag," however, appears to stick, and is eminently appropriate. This flag continued to be used until the Continental Congress adopted the "Stars and Stripes." The socalled "Betsy Ross" flag, or the first "Stars and Stripes," is enmeshed with much romance, but the testimony as to the events rests pretty largely on the statements of Mrs. Ross herself and these are not supported by contemporary writers. Her house still exists at 239 Arch Street, Philadelphia, and is cared for by the American Flag House and Betsy Ross Memorial Association, and is a memorial to the little widowed OCT. 28, 1776 The facts, however, seem to have been these: On June 14, 1777, the American Congress adopted the following resolution: Resolved, That the flag of the thirteen United States be thirteen stripes, alternate red and white; that the Union be thirteen stars, white on a blue field, representing a new constellation. JUNE 14, 1777 John Adams has the credit of proposing the committee that framed the resolution. Washington is said to have remarked, "We take the star from Heaven, the red from our mother country, separating it by white stripes, thus showing that we have separated from her, and the white stripes shall go down to pos- apocryphal. The design was not officially promulgated until September 3, 1777. The stars were first arranged in a circle, but this gave way to three horizontal lines of four, five and four stars. This remained the national emblem until May 1, 1795, when two more stripes and two more stars were added for Vermont and Kentucky. spired when he witnessed the bombardment of Fort McHenry, September 13, 1814. He was trying to obtain the release of a friend who had been captured by the British. Key was on this expedition, which had his vessel, lest he disclose the intended attack on Baltimore. He was compelled, therefore, to witness the bombardment through the whole day and night, and when he saw the national emblem still floating in the breeze in the morning, his muse compelled him to write this national anthem. The song was first published in the Baltimore American, September 21, 1814. Originally, the song was written on the back of a letter and was copied out in full at night, in a hotel in Baltimore. It was struck off in handbill form and its popularity was widespread. Ferdinand Dura rig fitted the music of "Anacreon in Heaven" to the words. This remained the national flag for twenty-three years. It was used during the war of 1812. By 1818 five additional States were added; Tennessee, Ohio, Louisiana, Indiana and Mississippi were admitted into the Union, so that further changes In the flag were required. The act of April 4, 1818, provided first, "That from and after the fourth day of July, next, the flag of the United States be thirteen horizontal stripes, alternate red and white; that the union have twenty stars, white in a blue field." Second, "That on the TEEN STRIFES admission of every new State into the Union one star be added to the union of the flag; and that such addition shall take effect on the 4th of July, next, succeeding such ad- mission." The return to the thirteen stripes was due not only to a reverence for the flag of the Revolution but also to the fact that a further increase in the number of stripes would have thrown the flag out of balance, or would have made the stripes so thin that they would be indistinct at a distance. Since this time no change has been made in the flag except to add stars as required. In the war with Mexico the flag had twenty-nine stars in the union, thirty-five during the Civil War, and since July 4, 1912, forty-eight stars. Considerable confusion existed as to the way the stars should be placed. The official arrangement followed by the Army arid Navy is as follows : Rev. S. Francis Smith, D.D. Dr. Lowell Mason, one of the fathers of music in this country, turned over to Dr. Smith some foreign music and asked him if he found anything particularly good to write words for the music. The latter found the tune of "God Save the King," and wrote the remarkable lyric at Andover, Mass., in February, 1832. It was struck out at a sitting with no idea of its future popularity. The first time it was publicly sung was at a children's celebration of American Independence, at the Park Street Church, Boston, July 4, 1832. flag was adopted, May, 1863. This also was found to be objectionable, having the appearance of a flag of truce, so a broad transverse strip of red was added, so we have the third flag of the Confederacy. This was adopted February 4, 1865, The real battle flag was like the one pictured below. BATTLE FLAG OF THE CONFEDERACY Our flag now waves over a united country and over colonial possessions of vast territory and wealth, and has also waved over Morro Castle, when we set the Cubans free, but it did not reajajn over that historic struc- ture, for we did not invade Cuba with any thought of conquest but to free her from the oppressor. . On Memorial Day. May 30th, the Flag should fly at half staff from sunrise to noon and full staff from noon to sunset. STARS AXD STRIPES Is the official name of the national flag of the United States. In the Army our national flag is called the Standard, also the Colors. When borne with another flag, the regimental color, the two flags are called a "Stand of Colors." In the Navy our national flag is known as the United States Ensign. sunset. At "Retreat" sunset, civilian spectators should stand at "attention" and uncover during the playing of the "Star Spangled Banner." Military spectators are required by Regulation to stand at "attention" and give the military salute. During the playing of the National Hymn at "Retreat" the flag should be lowered but not then allowed to touch the ground. When the flag is flown at half staff as a sign of mourning, it should be hoisted to full staff at the conclusion of the funeral. In placing the flag at half staff, it should first be hoisted to the top of the staff and then lowered to position, dropping it from the top of the staff the distance of the width of the flag, and preliminary to lowering from half staff, it should first be raised to the top. Where several flags are displayed on poles with the national flag, the Stars and Stripes should be hoisted first and on the tallest and most conspicuous staff. Where two flags are dislayed, one our National flag, it should be placed on the right. (To ascertain the right of a building, face in the same direction as the building.) No flag should ever be flown from the same staff as the United States flag, except in the Navy ; then only during Divine Service, when the Church Pennant may be displayed above the national flag— God above Country. When, in parade, the national flag is carried with any other flag, it should have the place of honor, at the right. If a number of flags are carried, the national flag should either precede the others or be carried in the center, above the others, on a higher staff. When flags are used in unveiling a monument, tablet or statue, they should not fall to the ground, but be carried aloft, forming a distinctive feature of the ceremony. When the national flag is used as a banner the union should be at the right (as you face the flag). When used as an altar covering, the union is at the right (as you face the altar), and nothing should ever be placed upon the flag except the Holy Bible. PORTRAYING THE FI.AO To properly illustrate the flag, the staff should always be at the left of the picture with the flag floating to the right. When two flags are crossed, the national flag should be at the right. If the national flag is pictured as a banner, the union is at the right. in parade or in review, the spectator should, if walking, halt, and if sitting, arise and stand at "attention" and uncover. naval trophy flags in the world. seas, victories won by the consistently maintained skill and efficiency. as well as by the traditional daring and devotion to duty, of our officers BRITISH ROYAL STANDARD This gorgeous blazoning of the arms of England, Scotland, and Ireland, together with the arms of the Hanoverian dominions in Brunswick, Lunenburg and Saxony, is said to be "the only British Royal Standard ever captured in battle." And indeed, this great standard, which measures thirty feet by twenty-fivfe, was taken at the attack ou York (now Toronto), when that place, then the capital of Upper Canada, was captured by the squadron under Commodore Isaac Chauncey and a land force under General Pike, April 27, 1813. Nevertheless, it should be remembered that the royal standard 1ms for centuries ceased to be a battle flag, that it is used primarily to signify the presence of the sovereign, and that it was found at the Parliament House at York, where it awaited the visit of a member of the royal family. It was in retaliation for Chauncey's raid on York, and more especially, perhaps, for the taking of the Royal Standard from the Parliament House, that the Britisli sont General Ross's army against Washington in 1814, and burned the public buildings at our capital. the Stars and Stripes side by side with the Stars and Bars of the Confederacy ; their age, their faded colors, and the security of their repose as they hang in draped folds THE BATTLE FLAG C2 LAKE ERIE In the Flag Room at Annapolis, whose high ceiling and walls are ablaze with captured trophies, the place of honor is assigned to the "DON'T GIVE UP THE SHIP" flag; its message and its story are woven through the threadbare strands of every flag in the collection. This battle flag of the squadron under Master Commandant Oliver Hazard Perry, and his signal for going into action, was flown successively on his flagships the "Lawrence" and the "Niagara," at the battle of Lake Erie, September 10, 1813. Made at Erie by Perry's order, at the suggestion of Purser Samuel Hambleton, it bears on a dark blue field, in white letters rudely fashioned by the hands of jack tars, the dying words of Captain James Lawrence, mortally wounded in the action between the United States frigate "Chesapeake" and the British frigate "Shannon." When the British squadron came in sight of Perry's men, their commander jumped on a gun-slide, and addressed the crew of the flagship: "My brave lads, this flag bears the words of Captain Lawrence. Shall I hoist it?" Wild cheers from their bared throats were echoed from the other ships of the squadron as the bunting was run up to the mainroyal masthead. The men took their places at the guns. In the battle that ensued. Perry saved the Great West, and won a complete victory, which enabled him to send his famous message to General Harrison: "We have met the enemy and they are ours — two ships, two brigs, one schooner, and one sloop." The flags of all these vessels are in the Navy Collection, but the commanding position is assigned to this battle flag, with its message: "DON'T GIVE UP THE SHIP!" behind the glass of their exhibition cases, are significant reminders that we are at peace with those who in the past were enemies, and significant object lessons chat the honor kept at the Naval Academy, where, for many years, the flags were exhibited in the old Naval Institute Hall. In 1900, however, when this building was about to be torn down, the trophies were packed In sealed boxes, to await the day when they should be properly preserved, and placed on exhibition in the new buildings of the Naval Academy, in which alcoves and paneled spaces had been planned for their reception. It was known that the flags, when packed away, were in poor condition, and it was feared that in spite of all precautions they would be damaged by moths. Efforts to have ings and grounds at the Naval Academy, began a correspondence which included the naval committees of Congress, patriotic societies, and the custodians of flag collections the world over. In the course of this correspondence, a letter was received from the Hon. Curtis Guild, ex-Governor of Massachusetts, in which Governor Guild named as his choice of an expert on flag preservation Mrs. Amelia Fowler, of Boston. At the request of Commander Cole, Mrs. The "Guerriere," Captain James Richard Dacres, was defeated and-captured by the famous "Constitution," Captain Isaac Hull, on August 19, 1812, in the first of the frigate actions of our second war with Great Britain. "The sea-spell of England was broken," and although the "Constitution" herself fought two more splendid actions under the command of Bainbridge and Stewart respectively, against the "Java," and against the "Cyane" and the "Levant," the American people have never forgotten the first flush of pride which they felt when they heard the news of Hull's triumph. Among all the single-ship victories won by American naval officers in the War of 1812, the classic of the honor roll is the fight between the ship we have come to love as "Old Ironsides" and His Majesty's ship "Guerriere." To Commander William Carey Cole, U.S.N., more than to any other individual, but also to Captain John H. Gibbons, U.S.N., then Superintendent of the Naval Academy, who supported Commander Cole in his work, is due the credit for the accomplishment of the restoration of the flags. Early in 1911 Commander Cole, as officer in charge of build- contract for their preservation. Her special process consisted in spreading the tattered remnants of each flag upon a backing of heavy Irish linen of neutral color. This delicate work was guided by the original measurement of the flag, by a knowledge of its design, and by placing in lines at right angles the disarranged strands of the warp and woof threads in the fragments of bunting. What remained of the original flag was then sewn firmly to the linen backing by needlewomen, under Mrs. Fowler's instruction and the original, the stitches, dyed to match the adjacent edges of the old bunting, complete the design of the flag, and tell graphically the story of the pieces that are gone. On April 8, 1912, Congress passed an act appropriating $30,000 for the work of preservation and preparation for exhibition. Shortly before This is the only Confederate flag placed on exhibition in the great trophy collection of the United States Navy, and it has been placed side by side with the ensign of the United States sloop-of-war "Kearsarge," to symbolize the Union of the North and the South. The. "Albemarle," long the terror of her enemy's wooden vessels, was sunk with a spar torpedo handled from a picket launch by Lieutenant William Barker dishing, at Plymouth, Roanoke River, North Carolina, on the night of October 27, 1864. dishing, "the bravest of the brave," whose intrepid deed matches if it "does not excel the burning of the "Philadelphia" in the harbor of Tripoli by Stephen Decatur, by this one stroke put an end to the war in North Carolina. His well-nigh miraculous survival enabled him to see this trophy of his exploit, the flag flown on the "Albemarle," which was taken shortly after his exploit, at the capture of Plymouth by the Union army. guidance. The stitches, of silk or linen thread, cover the entire surface of the flag, with circular meshes — a network very strong, yet hardly visible, since the thread is carefully dyed to match the colors of the old flag, however faded or stained in varying degrees. Where there are gaps or missing parts in this act was passed, Commander Cole held up, before the members of the House of Representatives, as an impressive witness, the disintegrating fragments of Oliver Hazard THE AMERICAN FLAG the Ship." The sight of this trophy in such a deplorable condition was a final argument for the appropriation to which the House and the Senate could not but respond, and to which they responded with admirable generosity. On July 12, 1912, Mrs. Fowler's needlewomen, who averaged forty in number began the arduous labor of sewing over by hand every square on the ground that the honor of cataloguing the collection fell to me, and as some account of the work of cataloguing, which occupied two years, is also requested, it seems proper to state that Commander Cole entrusted to me the work of verifying the identity of all the flags, discovering, if possible, the data concerning certain flags of unknown history, settling questions of This is the last flag hoisted by Admiral David Glasgow Farragut, conqueror of the Mississippi and victor of New Orleans and Mobile Bay. It was flown at the masthead of U.S.S. "Tallapoosa," his last command, and was hung at half-mast during the naval obsequies of George Peabody, at Portland, Maine. Looking up at this flag as a salute was fired at Portsmouth, New Hampshire, in Admiral Farragut's honor, he remarked, "It would be well if I died now, in harness." He died shortly afterward, on August 14, 1870. Until very recently, when Congress established the rank of Admiral, the only officers of our naval service who flew the flag with four stars were Farragut, David Dixon Porter, and George Dewey. inch of the flags. Some idea of the magnitude of the task will be had when it is explained that the collection contains no less than 15,00o square yards of bunting. The flags were completely restored, and placed on exhibition with great skill, by May 16, 1913. The work had occupied ten months. account of the flags for this book the best plan of exhibition, and writing the official inscriptions, or the catalogue proper. When I took up this work, I found confronting me a task difficult in some ways, if not impossible. Evidence was not lacking that a considerable number of the flags had been confused with other flags. To mention a few of these cases — since corrected in every instance— the ensign of the British frigate Cyane was listed as the ensign of the Guerriere, and the jack of the Guerrtere was listed as the jack of the Cyane; there were five other errors in the identity of British flags ; even flags captured during the Spanish War had been incor- inscriptions on the hoists of the flags, by eliminating each certainty in identification as it appeared, and by collecting all possible information from individuals who knew certain flags, the problem narrowed down to three or four cases. At last, these The battleship "Maine," commanded by Captain Charles Dwight Sigsbee, was blown up while at anchor in the harbor of Havana, Cuba, on the night of February 15, 1898. This flag— its colors intermingled by the action of salt waterwas recovered from a locker of the "Maine" after her destruction. It is thought to be the flag lowered at sunset on the evening of February 15, 1898. So far as is known, no poem has been written about the flag of the "Maine" to stir the hearts of Americans. Perhaps there is no need of a poem to summon up the memory of that ship; monuments attest the fame of her gallant dead, and her flag stands among the trophies of the Navy— symbol of the honorable keeping of a nation's word, disclaiming desire for conquest, and of the freedom of Cuba. rectly labeled and numbered. The old catalogue, published in 1888, was untrustworthy, and subsequent errors had made it virtually useless. Gradually, by dint of gathering all the evidence available in the form of were disposed of by the discovery of some old drawings and photographs. In the course of this work, the history of all but two of the flags of unknown history was determined. Static and Dynamic Aircraft — The Drift Balloon — Captive and Kite Balloons— Dirigible Balloons — History and Mechanics of the Aeroplane — The Development of Military Aviation — Scouting Aeroplanes — Fighting Aeroplanes — Bombing Aeroplanes — The Seaplane — Aeronautics in America A ERONAUTICS, the science of A\ aerial navigation, and its vehicles, generically termed aircraft, subdivide into two distinct branches and types, respectively. The science dealing with machines which are supported by a gas lighter than air, i. e., static aircraft, is called aerostation; its vehicles are the drift balloon, the kite balloon and the dirigible balloon, all of which, it should be noted, possess the faculty of staying aloft without expending motive power. The science dealing with machines which are supported by the pressure onrushing air exerts on cambered surfaces, i. e., dynamic aircraft, is called aviation; its vehicles are the glider and the aeroplane, of which, however, only the latter possesses practical value, gliders being only used for experimental purposes. Unlike static aircraft the aeroplane cannot remain motionless in the air, for its ability to stay aloft is conditional upon its faculty to create air pressure by continuous motion. This obvious drawback may some day be obviated by the helicopter or direct-lift machine, in which sustentation is sought to be attained independently of horizontal motion by the use of vertical lifting screws. This type of machine is still in its experimental stage; such is also the case of of the ornithopter or wing-flapping machine, which seeks to copy the movements of the bird's wing-beats, and of the soaring machine, which is supposed to fly by the use of favorable air-currents. THE DRIFT BALLOON The drift balloon (or aerostat) was invented by the Montgolfler brothers of Annonay, France, who built in 1783 a balloon supported by heated air. Before the close of the same year the crude hot-air balloon (called montgolflere) met a much more scientific rival which shortly succeeded in eliminating it : this was the charHere, so named after the physicist Charles, who substituted hydrogen for hot air and invented nearly all the fitments of the modern aerostat. Hydrogen gas has a lifting power of about 60 pounds per 1,000 cubic feet and remains the most efficient static motor to the present day ; but as its production is expensive, sporting balloons are generally inflated with coal gas, which was invented in 1821 by George Green, of England. Coal gas, however, lifts only about 35 pounds per 1,000 cubic feet. A modern aerostat consists of an envelope, made of varnished silk, calico or rubber-proofed fabric impervious to gas, which is inflated through a long neck on the under side, called appendix. The envelope is surrounded with a net, the bottom of which is constituted by a suspension ring to which the wicker basket carrying the aeronauts is toggled with eight ropes. The top of the envelope is provided with a valve which allows part of the gas to escape whenever the aeronaut wishes to descend. Upon landing, the balloon must at once be disinflated in order to avoid being dragged; this is achieved by the ripping panel, which covers a vertical seam in the envelope and is operated by a rope whereby the balloon can be torn open instantly. The equipment of an aerostat comprises : ( 1 ) a guide-rope, which enables the pilot to maintain his vertical equilibrium, when near the ground, without expending ballast, the balloon being then relieved of part of its weight by the rope trailing on the ground; (2) ballast, constituted by sand carried in bags, and (3) various recording instruments such as a barograph, a statoscope, a compass, etc. In the days when self-propelled aircraft were inextant, the drift balloon had a wide usefulness not only in the field of scientific and sporting achievement — where its value remains unimpaired — but also as a vehicle of transportation. This was conclusively demonstrated during the siege of Paris in 1870-71, when the besieged garrison organized a balloon-mail service by means of which 164 voyagers — amongst whom Gambetta — and 3,000,000 despatches were carried over the Prussian lines. Out of sixty-six balloons only five were captured by the enemy and two were lost in the Atlantic ; and so great was the moral and material success of this enterprise that Bismarck threatened to shoot every aeronaut as a spy, and Krupp produced the first anti-aircraft gun. Although the dirigible balloon and the aeroplane have now entirely eliminated the drift balloon from military use, it seems certain that the aerostat will always retain its value for scientific and sporting achievements. cable attached to the ground. Such was the famous Entreprenant, which afforded General Jourdan, commanding the French army at the battl% of Fleurus (1794), such an excellent view of the enemy's movements, that it actually turned a near French defeat into a brilliant victory. Such was also the gigantic sightseeing balloon Giffard built for the Paris Exhibition of 1878 ; this craft, which had a volume of 882,500 cubic feet, carried thirty-eight passengers at a time to a height of 1,600 feet, and was hauled down by a 300 horsepower steam winch. This balloon has remained the largest spherical of either drift or captive type. pected, the lesson of the battle of Fleurus was lost to military science and it was only after the FrancoPrussian war that the military establishments of the principal nations adopted the captive balloon for purposes of observation in field and siege warfare. In this function captive balloons played a certain role during French and British colonial expeditions ; nevertheless their usefulness proved to be a limited one on account of their inability to stand up in a strong wind. The defects of the ordinary captive balloon were overcome by two German army officers, Captains Parseval and Sigsfeld, who produced in 1898 the so-called kite-balloon — a craft which has proven so successful that it is now recognized to be an indispensable auxiliary of every up-to-date army and navy. The kite-balloon consists essentially of an elongated gas-bag which is divided into two unequal portions, the larger of which (comprising about four-fifths the total volume) is filled with hydrogen ; the remaining one-fifth constitutes the ballonnet, or air-cell, and this is automatically inflated by the wind through a convenient aperture. The ballonnet fulfills two purposes : first, it creates within the gas-bag a sur-pressure equal to the pressure of the wind plus the static pressure of the hydrogen, thus enabling the balloon to maintain its shape regardless of any wind the mooring cables can with- stand; and secondly, air being much heavier than hydrogen, the air-cell causes the balloon to assume an inclined position, which is particularly favorable for counter-acting the depressing tendency of the wind. In order to keep the craft always headon to the wind a sausage-shaped air bag rudder is fitted to the rear of the envelope, which is inflated the same way as the air-cell; longitudinal stability is further insured by a number of sails and a device similar to a kite's tail. The standard type of kite-balloon has a volume of from 25,000 to 35,000 cubic feet, and it carries one or two observers who are connected by telephone with the artillery unit they are attached to. As a fire-control station for military, and even naval operations of a stationary character (siege, blockade, etc.), the kite-balloon far surpasses the aeroplane, affording, as it does, a steady platform wherefrom field glasses or telescopes can be used to great advantage. In the Great War the kite-balloon is chiefly being used on the western front, where hundreds of them dot the rears of the Allies' and German lines. Their importance in effectually regulating artillery fire was particularly well demonstrated in the aerial operations which preluded the battle of the Somme. 3. few days before the big Allied "drive" began, British and French fighting aeroplanes methodically attacked every kite-balloon which stood watch over the German lines in that sector, fifteen being set on fire and destroyed and the remainder being driven down. It was only after the German commanders had been thus deprived of their fire-control stations that the Allied drive started with its bombardment and subsequent infantry attack. As kite-balloons do not possess any means of defense it becomes necessary to provide their occupants with parachutes so that they might escape with their lives should the balloon be carried away by a storm or be set afire by enemy aviators. Notwithstanding the latter contingency, which incidentally can be neutralized in some measure by the cooperation of anti-aircraft guns and friendly fighting aeroplanes, kiteballoons appear to be decidedly superior to aeroplanes in the function of directing artillery fire because of the former's ability to hover over a place, which aeroplanes do not DIRIGIBLE BALLOONS The dirigible balloon is the logical outcome of the Montgolfier brothers' ambition — which prompted their invention— -to navigate the atmosphere at will in lieu of drifting slavishly before the prevailing wind. The basic elements of a dirigible are (1) an elongated gas-container, called hull or envelope, and so shaped in order to attain the greatest speed with the least expenditure of motive power; (2) one or more cars or nacelles containing the power-plant, which drives a number of propellers. the fuel supply, the crew and the passengers, and eventually a commercial or military load; (3) a system of connection between cars and hull; (4) such means as will assure the permanency of the hull's shape ; and (5) such means of control as will effectually regulate the longitudinal and vertical equilibrium. A century elapsed before all these requirements could be successfully filled. This is why the invention of the dirigible cannot be attributed to one sole man, but is rather due to a series of inventions, such as that of the ballonnet, of the stabilising fins and of the horizontal rudder, and finally of the gasoline engine, which latter has, more than anything else, made the actual success of the dirigible possible. The existing dirigibles may be divided, according to their mode of construction, into two classes, viz., (1) pressure airships in which the permanency of the hull is insured by maintaining within the flexible en- velope a pressure superior to the atmospheric pressure, and (2) ri(?i<l or structure airships, in which the same object is attained by means of a rigid framework covered with fabric which encloses a number of drumshaped gas bags. Pressure airships further subdivide into vessels of the SUSPENSION non-rigid and semi-rigid type, according to whether the car or cars are directly hung from the envelope by means of steel cables or are suspended from a metal keel attached to, or built into, the hull. Of the former type are the Astra-Torres, (he Clement-Bayard, the Parseval and the Zodiac airships; the CroccoKicaldoni, the Forlanini, the GrossBasenach and the Lebaudy dirigibles pertain to the latter. But whatever the mode of suspension, all pressure airships have as a common feature the ballonnet, a collapsible air-cell located at the bottom of the hull, which can be inflated with air by a ventilator whenever the gas contracts through a change of temperature or of atmospheric pressure so that a constancy of displacement may be realized. The ballonnet compensates losses of volume, but not ones of lift (air being about fourteen times heavier than hydrogen) ; a decrease of lift can be made good only by jettisoning ballast (sand or water). An excess of pressure within the hull caused by an expansion of the hydrogen is relieved by automatic valves, which are fitted to both hull and ballonnet ; but as the ballonnet valves open at a less pressure than those of the hull an excess of pressure will first be relieved by an expulsion of air from the ballonnet. If, therefore, the latter has a sufficient capacity, no losses of gas will occur in the process of regulating the vertical equilibrium. On some pressure airships two ballounets are fitted, one fore and one abaft, which can respectively be pumped full of air and thus steer the vessel up and down by static means ; it is more common, however, to effect this function dynamically, i. e., by fitting the airship's stern with a horizontal rudder, called ele vator, which acts by the virtue of the pressure onrushing air exerts upon an inclined plane. In addition to an elevator and a vertical rudder, for steering right and left, most airships are fitted with horizontal and vertical fins, which serve the purpose of checking any pitching and yawing tendency. The engines used on airships differ but little from the well known automobile type, except that particular care is taken in their design to obtain the least possible weight and a low fuel consumption; the best airship engines (Chenu, ClementBayard, May bach) do not consume more than one-half pound of fuel per horse-power in one hour. Propulsion is effected by air-screws, which are generally mounted on outriggers on either side of the cars. Rigid airships need no ballonnet. the shape of their hull being rendered permanent by the framework. This system has the advantage of being supported by independent gasbags so that if one of these should accidentally become disinflated the airship could still continue its journey.' This feature is particularly valuable for military service and it has enabled many a Zeppelin — the most successful rigid airship to date —to escape destruction after having been hit by enemy fire. A remarkable proof of the value of the sectional construction of rigid airships was furnished by a Zeppelin which collided with a tree and had its bow ripped open by the impact ; the damage was quickly repaired by taking off three front compartments and by lightening the front car. whereupon the airship concluded its journey, a matter of ninety miles. A similar accident, had it happened to a pressure airship, would have caused the destruction <>f the vessel. The great difficulty confronting the operation of Zeppelins is the mooring of these enormous vessels in the open, for unlike pressure airships they cannot be instantly disinflated in case of an impending hurricane ; but this drawback, which has caused the loss of a score of Zeppelins, is now being overcome by the increased skill of the airship crews and by a perfected system of anchoring, but chiefly by a great number of "airports," which the Germans have fitted with elaborate sheds, hydrogen generating plants, workshops, etc. Sacconey used for military observation Before the Zeppelins had become notorious in the Great War as engines of indiscriminate destruction they achieved a more legitimate fame as pleasure craft. For several years previous to 1914 the German Airship Navigation Company of ful passenger service in which no passenger ever lost his life, although several accidents marked the operation of the air liners. The Zeppelins engaged in this service were fitted with a luxurious cabin-car, seating twenty-four, and a cold restaurant service was provided. A look-out post fitted on top of the hull, which could be reached from the bow-car by means of a stairway enclosed in a chimney, enabled the airship commander to navigate by astronomical observation. While private enterprise thus developed the air-liner the German military authorities created the aircruiser — a Zeppelin in which the pleasant cabin-car holds bombs of the explosive and incendiary kind and mounts machine guns, and lately, even small quick-firers for warding off enemy aeroplanes. Outside of Germany the value of the rigid air-cruiser with its great range and carrying capacity was either overlooked or contested, although in 1912 the first naval Zeppelin covered on its trial run a distance of 1,200 miles in 31 hours, with a crew of 31 and a wireless outfit carrying 200 miles. When the war broke out the Allies possessed only pressure airships of low range and slow speed, as compared to the dozen Zeppelins Germany was able to line up; this explains the marked superiority in long-range scouting the Germans possessed during the initial onrush on both fronts. The Allies clearly perceived their Inferiority in this respect and also their inability to produce in a short time rigid airships which would meet the Zeppelins on even terms ; so they set upon developing the bombing aeroplane and the anti-aircraft gun. Gradual improvement both in these weapons and in the skill of their operators soon cut short the Zeppelin's value for overland scouting, reducing its activity to night raids on more or less defended towns, which achieved, however, little military damage. The greatest present asset of the Zeppelin seems to be its faculty to act as a fleet auxiliary for strategic reconnaissance, because it exceeds in this respect not only the radius of action but also the climbing ability of seaplanes. If it be realized that a Zeppelin can see, from a height where it is little vulnerable, four times as far and travel twice as fast as the swiftest scout-cruiser, the extraordinary handicap the British Grand Fleet had to cope with in the battle of Jutland may readily be understood. Although of much less potentiality than the Zeppelins, the pressure airships of the Allies have been found very useful for anti-submarine defence, mine-sweeping and minor scouting operations. It seems, however, that should the dirigible survive in spite of the aeroplane, which is quite possible, the rigid system will likely prove the ultimate type, there being a limit of size beyond which it will be neither practical nor economic to build pressure airships. It is interesting to note how rapidly standardized airships can be built in large quantities: since the outbreak of the Great War the three factories of the Zeppelin Company have turned out airships at the rate of one in three, four and five weeks, respectively. By July. 1916, one hundred and ten Zeppelins had been launched, including twenty-five prior to the war; it is true, on the other agency of war. Owing to its great vulnerability the military future of the Zeppelin seems rather uncertain ; its commercial possibilities, however, appear to be more promising for the immediate future and more especially so for a trans-Atlantic service. AEROPLANE The aeroplane is— just like the dirigible balloon — not so much one man's invention as the combined product resulting from experiments TWO - SEATER SCOUTING AEROPLANE (160 H. P.) OF THE U. S. ARMY AVIATION SECTION STARTING TO GET OFF conducted and theories worked out for nearly a century by several schools of investigators. The fundamental theory of the aeroplane was clearly set forth by an Englishman, Sir George Caylei/, as early as 1809, and actually furnished the basis upon which the modern aeroplane was subsequently built up. In 1846 another Englishman, Stringfelloiv, gave a practical proof of this theory by building a small aeroplane model driven by a steam engine, which made several successful flights under perfect balance; this machine was, in conformity with Cayley's theory, a monoplane. In 1866 F. 8. Wenham, also of England, invented the multiple surfaced aeroplane and \t was again Stringfellow Vho vindi- cated the claims of the new principle by a successful free flight . of a triplane model. Further important contributions to the dynamics of the aeroplane were made by A. Penaud, H. Phillips, Sir Hiram Maxim and 8. P. Langley, late secretary of the Smithsonian Institution. The latter built, in 1903, a man-lifting aeroplane, which, but for its defective launching device, would have flown under control just as it did eleven years afterward with its original rotary motor. The first aeroplane to have actually left the ground, carrying a man, was the bat-shaped machine with which C. Ader, of France, made, from 1890 to 1896, several short flights. The balance of this machine, however, was poor, and it was only after the German O. Lilienthal had discovered by prolonged gliding experiments -the means of sontrolling the balance of flying machines that progress became practical. Lilienthal's gliding experiments were repeated and perfected in this country, under the guidance of O. Chanute, by the Wright brothers, of Dayton, Ohio, who gave the aeroplane its one missing link, the warping mechanism for insuring transverse equilibrium ; having thus brought the dynamic flyer under three-dimensional control, the Wright brothers fitted their glider with a gasoline engine driving twin propellers and succeeded in making their first power-flights on December 17, 1903, on the beach of Kitty Hawk, N. C. The Wright brothers, therefore, fully deserve the credit of having rendered practical — in other words, invented — the aeroplane. plane are: (1) the main surfaces, or wings, of which there are one or more pairs (in the latter case superposed or in tandem) according to whether the machine is a monoplane or multiplane (biplane, triplane, quadruplane, etc) ; (2) the auxiliary surfaces or control organs which regulate th£ machine's balance and direction (ailerons, fins, elevator and rudder) ; (3) the bodywork or fuselage, which forms the bridge between the wings and the tail and affords accommodation for the passengers, the fuel tanks, the navigating instruments, etc. ; (4) the powerplant, composed of one or more engines actuating one or more propellers, whose position ahead or abaft of the wings causes the aeroplane to be called a tractor or pusher; and (5) the undercarriage, which is fitted with either wheels or floats, or both, for starting from and alighting on land or water, or both. The seaplane or marine aeroplane is the invention of Henri Fabre, of Marseilles, France, who made the first flight from the sea on May 21, 1910, at Martigues. The "flying boat," whose development is chiefly due to Glenn H. Curtiss and M. Denhaut, is a seaplane in which the bodywork is combined with a central boat of large flotation, thus do- AMERICAN-BUILT SPEED SCOUT FITTED WITH A 100 H. P. STATIONARY CURTISS MOTOR. HORIZONTAL SPEED, 119 MILES PER HOUR. riage. Particular credit for having advanced the mechanics of the aeroplane is due to Louis Blerlot, E. Nicuport, J. Bechereau and R. Saulnier (monoplane construction) ; to the Voisin and Farman brothers (development of the pusher biplane) to Louis Brfyuet and A. V. Roe, the originators of the tractor biplane, and to Gustave Eiffel, whose aerodynamic research work has placed the aeroplane on a scientific basis. No less credit should go to the Seguin brothers for their invention of the Gnome motor, which has probably furthered the progress of aviation more than any other single invention and still appears as the prototype of the most promising aeroplane engine; and to L. Chauvierc, inventor of the wooden airscrew. Quite an important advance in aeroplane design was achieved in 1913 by a Russian engineer. M. Sikorski, who first conceived the idea of building aeroplanes of very large size, driven by several independent motors and capable of carrying a dozen people in a comfortable, heated and lighted cabin. In this country Glenn H. Curtiss has since successfully produced large seaplanes based on a similar principle. As soon as the aeroplane had proved its ability to effect voyages with sufficient reliability and its range, carrying capacity and climbing ability increased, military authorities all over the world were prompt in adopting it for purposes of reconnaissance. It was in this function that the aeroplane made its debut in the Great War and the services it rendered were so important that all the belligerents quickly decided upon greatly enlarging their aerial establishments. As specific examples of the work achieved by scouting aeroplanes one might mention how in the battle of Mons the British expeditionary force was saved from envelopment and possible annihilation by an aviator who reported that the Germans had twice the numbers that had been anticipated. Again, at the battle of the Marne it was an aeroplane reconnaissance which disclosed the gap between Von Billow's and Von Hausen's armies, and thus enabled General Foch to drive a wedge into the German lines, forcing them to retreat. The examples cited sufliciently emphasize the value of the aeroplane for scouting; but as both Allies and Teutons went to war provided with "aerial eyes," each party soon felt the need of preventing the enemy from seeing — and forestalling — the friendly moves. Such was the inception of what is to-day termed a "fighting machine." Then the necessity arose of destroying an important supply station or a railway junction of the enemy, which object could not otherwise be reached than by attacking the place fronr above : this necessity created tht bombing aeroplane. of scouting, fighting and bombing, every aeroplane being supposed to carry out all or any duty as the necessity arose. As a result no aeroplane was really efficient in any function. Curiously enough the Germans still adhere in some measure to this theory which the British and French air services rejected early in the war. The modern scouting aeroplane, as developed by the Allies, is a twoseater of great speed range — else a detailed inspection of the underlying is as a rule a highly trained specialist, who must be able to distinguish from a height of several thousand feet a convoy train from artillery, field guns from howitzers, or a supply station from an aircraft park, and be conversant with the Morse code, so that he may instantly send off his report by wireless telegraphy. To fly back to headquarters would mean too much loss of time. The observer's duty is the more difficult as the enemy below will do everything to mislead him, by setting up dummy guns and holding back his gun fire while the aeroplane hovers A FRENCH FIGHTING AEROPLANE objective becomes impossible — whose only task consists in observing a given objective and reporting the result in the quickest way possible. Its armament is purely defensive and generally consists of one machine gun firing broadsides and abaft (on tractors) or ahead (on pushers). The crew is composed of a pilot and an observer; the latter above; troop columns on march will stop and seek shelter ; positions which cannot be masked will be defended by anti-aircraft guns or possibly by fighting aeroplanes which the observer will have to fight off with his machine gun. "gun-spotting," which consists in conveying to the artillery the exact range of an objective to be shelled. These manifold duties of the observer explain why a scouting aeroplane must be a two-seater : the pilot is indeed kept busy enough in trying to keep to his right course wljile dodging anti-aircraft shells by flying in erratic zigzags. to effect a safe return. The wartime services of an aeroplane may attain a period of three to six months, although a good many machines last but a few weeks; rotary motors last 100 to 150 hours of service, provided they are thoroughly taken apart and cleaned after every 20 hours of service. Stationary engines last a good deal longer. two years of warfare — of which the monthly lists of the belligerents' aircraft losses bear eloquent testimony — nothing short of a direct hit into a vital part will down an aeroplane, provided its petrol-tank has not been set afire. Shrapnel balls and rifle bullets are little effective against aeroplanes flying at a height of 10,000 feet; a French scouting machine received 400 bullet holes while The tactical unit of the aviation service is the squadron, which consists (in the United States and British armies) of twelve machines of the same type, twelve motor trucks with their trailers for land transportation and of a repair-car, and several automobiles and motorcycles. The squadron subdivides into three companies (flights in the R. Flying Corps) of four machines each. Although scouting aeroplanes do carry defensive armament, it often becomes necessary to protect them against a concerted enemy attack. Such is the function of the fighting aeroplane, a high-speed, single-seater tractor, which can out-fly and outclimb any other type of machine. The pilot aims the machine-gun, which is rigidly fixed in front of him, by steering the aeroplane against the target ; the blades of the air-screw are armored and thus deflect the bullets which hit them. In this way about 30 per cent of the bullets go astray. This gun-mounting, which was invented by R. Garros, the famous French airman, has since been adopted by the Germans on their Fokker monoplanes with the one variance, however, that the gun is connected with a timing device actuated by the motor, so that it can fire only when the blades of the air-screw do not cover the muzzle. Quick maneuvering ability being one of the chief assets in aerial combat, it follows that fighting aeroplanes must be highly sensitive, in other words, neutrally equilibrated, so as to instantly respond to control ; this is why only pilots showing particular aptitude for aerial combat are entrusted with the operation of fighting machines. In addition to protecting scouting machines, fighting aeroplanes are also used for destroying kite balloons, convoying bombing machines on raids and even attacking Zep- pelins. Two Zeppelins were thus destroyed from small combat machines carrying but a few bombs, by the late Flight-Sub-Lieut. R. Warneford, R.N.A.S., and Lieut. W. L. Robinson, R.F.C., respectively, whereas aeroplanes of all types, as well as kite balloons, have been lost by the chief belligerents in numbers aggregating several hundreds. BOMBING AEROPLANES Fighting aeroplanes are but occasionally used as bombers and more especially in cases where quick climbing is imperative. Bombing raids proper are carried out by socalled bombing aeroplanes, in which high speed is forsaken in favor of great carrying capacity. The load of explosives such a machine carries can be apportioned either into a great number of light bombs or else into a few powerful missiles, some of which weigh as much as 300 pounds. Considering the first two years of aerial operations it appears that the French and the British achieved incontestable aerial supremacy in scouting and fighting only toward the close of this period ; it is therefore the more striking that the action of bombing aeroplanes, in other words the aeroplane offensive, should OF A BRITISH BOMBING AEROPLANE have belonged practically all the time to the Allies. The big bombing raids by French and British aeroplane fleets — some of them composed of fifty and sixty machines — against the airship sheds, railway junctions, shell factories, supply stations, submarine bases and coast defense works of the Germans, in the course of which immeasurable moral and material punishment was inflicted, certainly appear as one of the most striking phases of aerial warfare. An indication of what the battle aeroplane of to-morrow might be, is furnished by the French avion-canon; this is a large pusher, mounting on its bow a 1^-inch quick fire THE SEAPLANE The functions .of the seaplane ar1 to all intents similar to those of the aeroplane, viz., scouting in advance of fleets and naval bases, clearing the skies of enemy aircraft and bombing the enemy's coast establishments. Seaplanes work under a double handicap: first, all other elements being equal, their heavy floats greatly decrease the useful load which might otherwise be utilized for increasing their range or their load of bombs, and secondly, the design of seaplane-floats is not yet sufficiently advanced to permit alighting on or starting from a rough sea. Consequently flights of several hundred miles' length, which are common enough over land, are infinitely more difficult to carry out over the sea ; this is why all seaplane operations have — unlike the work of land machines— occurred in close proximity of permanent bases or mother-ships. Notwithstanding their limitations seaplanes have rendered exceedingly useful services as fleet auxiliaries, particularly in the Gallipoli campaign, where gun-spotting seaplanes directed the Allies' guns on targets invisible but from the air. Seaplanes have also played a notable r61e in patrolling the coasts of the warring nations and in detecting and even destroying submarines and plane pilot was recommended by Vice-Admiral Beatty in the following terms: "Lieut. F. J. Rutland, R. N., for his gallantry and persistence in flying within close range of four enemy light cruisers, in order to enable accurate information to be obtained and transmitted concerning them. Conditions at the time made low flying necessary." The present trend in the design of seaplanes (as well as of aeroplanes) appears to be toward ma- chines propelled by several motors and propellers, the purpose of which is to keep the machine aloft or at least capable of returning to its base even if one motor should break down or be destroyed by the enemy. THE SCIENTIFIC AMERICAN TROPHY donated with the object of fostering the art of aerial navigation, is now in the permanent possession of Mr. Glenn H. Curtiss, who won it three times in succession. The Great War has had a very beneficial influence on the American aircraft industry ; millions of dollars worth of aeroplanes and motors were purchased in this country by the Allies, chiefly for training purposes, and the profits derived thereby have enabled American manufacturers to develop aeroplanes and engines which begin to compare favorably with the products of Europe. Among the aeroplanes thus produced one might mention the huge multiple engined "flying boats" of Glenn H. Curtiss; a machine of this type is now being developed for crossing the Atlantic from Newfoundland to Ireland, a distance of 1,800 miles. The important services the aerial arms have rendered to the warring nations has awakened the American public to the realization that the United States needs — and has so far lacked — an air service adequate to its policies; as a consequence the Aero Club of America instituted the National Aeroplane Fund which, thanks to the generosity of patriotic citizens, has enabled the National Guard of various States to acquire aeroplanes and train aviators, and Congress appropriated a sum of over $15,000,000 for the development of aeronautics in the Navy and Army. On July 13, 1916, President Wilson crowned these measures by creating the Aerial Reserve Corps, which is nothing short of an aerial militia. The Post Office Department is furthermore considering the establishment of several aeroplane- mail routes. NO list of the greatest modern inventions fails to include wireless telegraphy and telephony. And it is perhaps equally true to state that no invention is regarded with as great awe by the laity. Yet wireless communication in its essentials is simple. There is nothing truly mysterious in wireless or radio telegraphy and telephony. The real beginning of wireless communication, or rather the propagation of electric waves through space and their subsequent detection at remote points, is largely a matter of opinion. Some authorities prefer to look upon Steinheil of Munich, Germany, as having taken the first step toward radio communication. For in 1838, Steiuheil, following the suggestion .of Gauss, demonstrated the feasibility of using the ground as the return circuit for a wire telegraph system, which in a measure is a form of wireless telegraphy in the embryonic state; and what i? more, the work of Steinheil caused much attention to be directed to the possibilities of communication without wires. Such names as Trowbridge, Preece, Rathenau, Strecker, Morse, Lindsay, Wilkins, and Melhuish have been associated with the conduction of electric currents through bodies of water and through moist earth, largely through the inspiration offered by Steinheil's pioneer work. Aside from the conduction method of communication suggested by the experiments of Steinheil, electromagnetic induction between parallel metallic conductors was suggested and studied by Trowbridge, Preece, Lodge and Stevenson. A combination of the conduction and induction principles also was the subject of much experiment, and under the guidance of Sir William Preece, aided by the British Postal Telegraph Engineers, it became the basis of a workable system of wireless communication for short distances. However, for several reasons this system did not lend itself to commercial purposes, and hence nothing came of it. Still another workable system of communication without wires was developed by Edison, Gilliland, Phelps and W. Smith, utilizing the principle of electrostatic induction between conductors spaced some distance apart. The latter system was primarily intended as a means of communication to and from moving railway trains. However brilliant may have been the conceptions of the various pioneer systems already referred to, the real dawn of commercially practicable wireless communication came witb the scientific investigation of electromagnetic waves, resulting in a clear understanding of the generation, propagation, and detection of these waves. Credit in large measure is due Maxwell, who, in 1865, announced his remarkable electromagnetic theory of light. But Max- well's work, despite its profundity and its rich and invaluable collection of mathematical data, was primarily theoretical. As a result, its full value as applied to the propagation of electromagnetic waves was not realized until 1888, when Hertz's discoveries and practical investigations again attracted attention to the subject. The work of this young German scientist corroborated the theories of Maxwell; and so rich in possibilities was the field opened by Hertz that numerous scientific workers in various lands set upon the task of acquiring further knowledge of the properties of the electromagnetic waves. Among the early workers in the field of electromagnetic transmission of power was Nikola Tesla, who, in 1892, conducted a series of spectacular experiments on high frequency electric currents. In passing it must not be forgotten that Prof. D. B. Hughes, according to a paper prepared by Sir William Crookes in 1892, developed a system of transmitting signals a few hundred yards without connecting wires, using a microphonic detector and telephone receiver for the receiving station. It appears that Prof. Hughes discovered the remarkable property of loose-contact filings to cohere under the influence of electromagnetic waves as far back as 1879 ; but because of the fact that he did not give his work sufficient publicity, some twelve years later Prof. E. Branly of Paris received all the credit for the wireless coherer, which played the leading part in the pioneer days of actual radio communication. Using Branly's coherer as a basis, wireless communication attracted the attention of Dr. A. Muirhead, Capt. H. B. Jackson, R.N., and Prof. R. Threlfall, as well as Prof. A. S. Popoff of the Imperial Torpedo School in Cronstadt, Russia, besides many other lesser known investigators. this time was more in the nature of laying a substantial foundation for what was to follow. Much of the work was indeed practicable; but none of the investigators had settled down to the development of commercial wireless communication. Then came Marconi. This young Italian scientist, born at Bologna, was keenly interested in the work of Prof. Rhigi of the University of Bologna, and it gave him the idea for commercial wireless telegraphy. June, 1895, witnessed the young Italian experimenting with sending and receiving apparatus on his father's estate, the Villa Griffone, near Bologna. To relate in detail the ramifications of Marconi's early work would require far more space than can be devoted to this entire wireless chapter, for the work he undertook was slow and painstaking. Although he had the advantages of using various ideas developed by the early investigators and of combining these into a wireless system, each idea by itself was crude and had to be systematically developed. These distances, covered with Marconi's early apparatus, speak volumes for the rate of progress made by him: 1895, 30, 100, and 2,400 meters, or 1% miles; 1897, 14 miles; 1898, 20 miles ; 1899, 85 miles ; 1900, well over 100 miles; 1901, transatlantic transmission of the letter "s" in the Morse code, over a distance of 2,200 miles. In the years that followed, the progress made was so rapid that long-distance communication has now become quite commonplace. Radio telegraphy, as we know it to-day, is not the invention of any one man. Not unlike all other great inventions it represents the labors of numerous investigators and inventors, many known to us and many more unknown to us. Among the better known later-day contributors to wireless telegraphy are Lodge, Muirhead, Salby, von Arco, Braun, Fleming, Fessenden, DeForest, Stone, Shoemaker, Blondel, Artom, Pickard, von Lepel, Poulsen, and Pierce. THROUGH SPACE It would be difficult to explain how electromagnetic waves, which are not susceptible to our senses, travel from a wireless transmitter to a receiver at the astounding rate of 186,300 miles per second, were it not for the simple analogy offered by a body of still water. Suppose a stone is thrown into a quiet pool of water. It will be noticed that waves or ripples form in perfect circles around the spot where the stone struck the surface, spreading out in ever-widening circles from the source. The ripples near the center are big aiM readily seen, while those some distance away are small and barely discernible, finally disappearing altogether, provided the body of water is sufficiently large. In other words, the ripples are largest near the source of •disturbance, but lose their strength in a gradual decrease the farther they are removed from the source. Although according to appearances the waves or ripples appear to form at the spot where the stone hit the surface, spreading out in ever-widening concentric circles, as a matter of fact they form at the immediate point where they appear. There is absolutely no transference of water from the center outward. Instead, a certain amount of mechanical energy is transmitted through the body of water, producing waves or ripples at intervals. The water merely acts as the conductor for the energy imparted to it by the impact with the stone. This may be readily proved by placing a small chip of wood at any spot a short distance from the source of the disturbance : it will be noted that the chip remains in the same spot, although it rises and falls following the up and down or rolling motion of the water upon which it rests. If there were the actual movement of the water from the center outward, the chip, obviously, would move along with the moving water Much in the same manner do electromagnetic waves react upon space, or, to use the name given to the medium through which these waves are propagated, ether. Nothing actually moves through ether in the transmission of signals by wireless; instead, the transmitting apparatus imparts energy to the ether, which in turn vibrates in much the same manner as the pond of still water. The vibrations spread through the ether in every direction, following the contour of the earth, until the force is spent. Ether, it is well to mention here, is a substance or medium imagined by physicists in order to explain the phenomena of light, radiant heat, and electromagnetic waves. The waves employed in radio communication range from 300 feet to 30,000 feet in length, measured from one crest to the next, just as in the instance of the ripples on a pond. X-rays, on the other hand, have a length of about 2.5 millionths of an inch; actinic rays of the maximum intensity, 10 millionths of an inch ; light rays, from 10 to 18 millionths of an inch ; and heat rays of maximum intensity, about 15 millionths of an inch. CEIVERS For wireless communication it is necessary to have a means of creating and imparting electromagnetic waves to the ether, and a means of intercepting and detecting these same electromagnetic waves at a remote point. The former is called a transmitter, or sender, while the latter is known as the receiver, or receptor. magnetic waves, created by the discharge of a condenser across a suitable air gap, are imparted to the ether by means of an elevated system of insulated conductors known as an aerial, and a connection with the earth or ground. The condenser receives its charging current from a transformer or induction coil, and whenever it becomes overcharged it discharges an instant later across a gap in circuit with it. Since the length of the wave generated by a spark discharge is governed by two factors, capacity (the measure for the storage capacity of the condenser) and inductance (the length of conductor in the wave-generating circuit ) , the circuit includes not only the condenser and spark gap, but a variable form of conductor or inductance, as well. The latter is always in the form of a flat spiral, or a helix. The adjustment of the capacity and inductance in the wavegenerating circuit is known as tuning, just as a musical instrument is adjusted to emit a note of a desired pitch. By inserting a telegraph key in the primary circuit of the transformer, or induction coil, it becomes possible to generate waves at will ; and by the proper manipulation of the telegraph key, an operator can emit different trains of waves to correspond with the dots and dashes of any telegraphic code. There are other methods of generating electromagnetic waves aside from a condenser charged by a high tension current furnished by transformer, or spark coil. Among them may be mentioned the high fre- erators of high frequency current have been built, and within the past few years considerable progress has been made along this line, despite the seemingly unsurmountable mechanical obstacles encountered at the beginning. A purely mechanical means of creating high frequency current suitable for the electromagnetic wfv'es employed in radio telegraphy and telephony is obviously the most desirable, which accounts for the persistent efforts of inventors along these lines. employment of some form of low tension arc, across the terminals of which are shunted a condenser and a variable inductance. With such an arrangement high frequency current is generated, the arc acting as the gap across which discharges the condenser. Whereas in the case of the usual spark transmitters the condenser discharges or electromagnetic wraves take place in the form of separate trains, each train or group comprising a number of sparks, each succeeding one less powerful than the one before, in the arc generator the waves are continuous and of the same, uniform strength. Thus the spark transmitters have come to be known as damped wave transmitters because of their damped waves, while the arc transmitters are known as undamped wave transmitters. The damping of the waves lends itself to an analogy in the form of a simple pendulum: In the undamped transmitter, the pendulum would be kept swinging an equal distance each swing, because the power would • be imparted so to accomplish this regularity ; while in the damped transmitter, the power would be imparted at one swing and not again for several swings, resulting in the pendulum swinging over a lesser arc each succeeding swing until the power were again imparted to the pendulum. The electromagnetic waves, either of the damped or undamped variety, chopped up in short and long trains to represent the desired characters of any telegraphic code, have now been propagated through ether. The problem is not only to intei'cept them but also to detect their presence. The first step in receiving electromagnetic waves is the erection of a suitable system of elevated, insulated wires, known as the aerial or antenna, which serves to intercept the electromagnetic waves, and to lead the currents induced in the wires down through the receiving instruments to the ground. which detects the presence of high frequency currents flowing down through the aerial and receiving apparatus. It is known as the detector. In the pioneer days of the art, a glass tube containing two electrode plugs between which was placed a small quantity of metallic filings, served the purposes of detector. The action of the filings coherer, as this detector is known, is simple: the high frequency current passing through the mass of loose filings possesses the property of causing these to cohere together so as to make a better contact between the two metal plugs. The lowering of the electrical resistance of the filings is sufficient to permit the current of a local battery to flow across the bridge thus formed and operate a relay, which in turn operates a Morse register that prints the signals in the form of dots and dashes on a paper ribbon. Some suitable form of tapper is used to shake the filings apart after the high frequency currents have ceased to flow through them. The tapper, known as the The filings coherer, while possessing the important advantage of allowing a Morse register to be used in conjunction with it, has long since ceased to be employed in commercial wireless work, although it remains the favorite form of demonstration apparatus for the classroom. It has given way to infinitely more sensitive detectors which are used in conjunction with telephone receivers worn on the head of the wireless operator. With the advent of more sensitive detectors the range of wireless transmitters has jumped from the tens of miles to the hundreds and even thousands of miles. So numerous and varied are the wireless detectors of to-day that even a superficial description Of each type is precluded by space limitations. Suffice it to state that among the most popular types of detectors are the crystal rectifier, utilizing cer- tain minerals and crystal formations such as iron pyrites, zincite, bornite, galena, silicon, carborundum; the electrolytic detector, which, while exceedingly sensitive, has given way to the first type because of the greater convenience of the crystal detectors; the magnetic detector, which would be a truly ideal type were it not for the fact that its sensitiveness is of a rather low order; and the audion, which is the most successful detector and the one in most general use to-day. Aside from the detector, a wireless receiving set comprises a telephone receiver or receivers, and adjustable condensers and coils for changing the capacity and inductance of the receiving circuit to tune it to any length of wave desired. If a transmitter is emitting waves of a length of 400 meters, for example, a receiving set must be tuned to the neighborhood of 400 meters in order to receive the waves. And while it is tuned to receive those waves, other waves of other wavelengths will not be heard in the receivers of the operator. Thus it is possible for several transmitting set? to be operating in one locality at the same time, while the same number of receiving sets are receiving, each from the desired transmitter, without interference from other transmitters. Tuned or syutonic wireless has reached a high degree of development to-day, although much remains to be accomplished. After having developed" their detectors to the highest possible degree of sensitiveness, wireless men were confronted with the problem of increasing still farther the range of receiving apparatus. Solution was found in the introduction of amplifiers, or magnifiers of the weak currents in the detector circuit. Some form of magnifiers are in reality an ordinary telephone circuit, in that the receiver, connected to the detector, is capped over a microphone transmitter, which in turn is electrically connected to a powerful bat- tery and another telephone receiver. Thus the faint sounds of the first telephone receiver are spoken into the microphone, which in turn impresses them on a circuit containing a loud-speaking receiver, or, at least, a receiver that produces loud sounds in the ears of the operator. Other forms of amplifiers utilize a modified form of the audion detector. In the one-step amplifiers of this type, an amplification or magnification of from 6 to 10 times is attained ; in the two-step amplifier from 60 to 100 ; and in the three-step from 600 to 1,000, according to Dr. DeForest, the inventor of the audion amplifier. Thus it will be appreciated that the sensitiveness of the detector is materially improved by the use of an amplifier; and it is the combination of highly sensitive detectors and amplifiers more than anything else that accounts for the remarkable long-distance communication of present-day wireless. TELEPHONY WITHOUT WIRES Wireless telephony differs from wireless telegraphy only in details ; for in general principles involved they are identical. If the wave trains of a spark transmitter were sufficiently close together to be above the range of audibility when received in the telephone receivers of the operator at the receiving station, it would be but a matter of a few slight changes, such as replacing the telegraph key with a microphone, to convert the average wireless telegraph transmitter into a radio telephone set. As it is, the requirements of successful radio telephony begin with a generator of undamped waves of very high frequency, so that the wave trains when received are above the range of audibility. Until recently some form of electric arc was, and still is, employed for generating the high frequency current for a radio telephone transmitter. Although on occasions fair success attends the employment of arc generators, a radio telephone system based on the use of such generators cannot be the ideal system of the future. An electric arc is necessarily unsteady ; its electrodes usually burn away at a high rate, resulting in sputtering and frequent readjustment to bring the electrodes closer together to make up for the consumption of electrode material. A constant variation in the consumption of current results in fluctuations in the high frequency current, which is fatal to clear transmission. Yet, despite the shortcomings of the electric arc as a generator of high frequency currents, much progress has been made with it by numerous investigators. has done much toward applying and improving the arc generator for wireless telephone purposes. More recently, Colin and Jeance of France have done considerable work on an arc telephone, on occasions succeeding in communicating over a range of several hundred miles. In America, Dubillier, Collins, DeForest and other investigators have in the past devoted considerable attention to the arc generator with a fair degree of success. Outside of the microphone, which must be able to handle large volumes of current without injury, in a wireless telephone set the arc generator is the center of interest; and likewise it is true that the generator is the point of divergence between the various systems. The Janke system, for instance, is a variation of the Poulsen arc, in that the arc is placed in liquid alcohol to insure greater steadiness. To impress the voice on the high frequency current, a special water-cooled multiple microphone is used. The TYK system, on the other hand, is not an American system like the former, but a Japanese system developed by Torikato. Its chief value lies in its utmost simplicity. The system consists of a 500-volt arc between points of burnt magnetite and brass, shunted by a circuit with a rather large capacity and a small inductance. A heavy -current microphone is placed in series with the aerial. Although it is supposed that the TYK system is really an arc system, the inventor is of the opinion that the result produced is a quenched spark of spark frequency beyond the limit of audibility. By a "quenched spark" is meant a discharge that does not oscillate to any appreciable extent ; in other words, the discharge rapidly dies out or it is highly damped. Various quenched spark systems have also been tried, notably that of Ditcham, but as a general thing systems based on the use of quenched spark generators do not possess good speech quality. The speech quality of the TYK system is reported to be poor, which confirms, to some extent, the belief that its generator is a form of quenched spark gap. tems have been used as far back as 1906 by Fessenden, but as in the case of their application to wireless telegraphy, even to-day they are considered largely in the light of experiments because of their prohibitive cost, their low frequency and consequently long wave length, and the difficulty of speed regulation. tems are the last word in radio telephony, and judging from the results obtained thus far with them there can be but little doubt that they possess the qualities of the ideal apparatus of the future. Marconi, DeForest, and others have, of late, investigated the possibilities of the reaction vacuum tube in connection with radio telephony. DeForest has developed a tube which is a modification of his audion amplifier. Known as the oscillion bulb or WIRELESS TELEGRAPHY AND TELEPHONY a potentiometer for close regulation, filament rheostat, impedance coils, loading inductance, telephone transformer coil, microphone transmitter, fixed condenser and minor accessories, a current supply for the filament and another of 150 to 300 volts for the production of the high frequency currents, forms a complete radio telephone for short distance transmission. For long distance work a number of oscillions are employed, together with a higher voltage — as high as 1,500 volts for a set with a range of 150 to 200 miles. Company who, in the latter part of 1915, succeeded in telephoning by wireless from Washington to Paris, and from Washington to Hawaii, the latter a distance of 4,900 miles. It is understood that a form of reaction vacuum tube was employed in large numbers in generating the high frequency currents required. At the present moment it seems that wireless telephony, long a laboratory experiment, is at last a commercially practicable means of communication. Even so, however, the great expense of installations for long distance work may cause its universal use to be postponed for years to come, although it is safe to prophesy the widespread employment of short-distance wireless telephone sets for ship-to-shore communication in the immediate future. TELEGRAPHY The later-day pioneers in wireless telegraphy, even in their wildest flights of fancy, never realized to what extent their work would play a part in the commercial world and in military and naval affairs. True, they prophesied the transmission of energy by means of electromagnetic waves on a vast scale, and even today there does not appear to be much promise of success along these lines. But the fact remains that communication without wires has been applied to a wide range of uses other than those originally planned. Ship-to-ship and ship-to-shore communication was the original aim of wireless men — radio telegraphy was to be a maritime invention. To-day the greatest employment of wireless remains on the water rather than on land ; and always will its greatest field be on shipboard. There is hardly an ocean-going vessel carrying passengers that is not equipped with wireless, for laws have been enacted obliging such ships to carry radio apparatus because of the security it affords the traveler on water. So numerous and powerful are the land stations operating in conjunction with the ships that it is very seldom indeed when a ship is out of touch with land. Ocean travelers receive the news of the world every day, which is flashed out by powerful stations in America and Europe. Serious work has been done in establishing radio telegraph and telephone communication between moving trains, notably that of the Lackawanna Railroad. Although on certain occasions a range of between fifty and one hundred miles has been covered between a moving train and fixed station, the results on the whole have not been satisfactory. Perhaps it is that the tests have been premature, and that a suitable system of communication, so.mewhat different from existing ones, must be developed for this particular purpose. Employing an aerial eighteen inches above the roof of a steel car, which is obviously grounded through the rails, it becomes evident that it is almost impossible to secure any distance with a wireless apparatus installed and operated under these conditions. The European War has given especial impetus to wireless, particularly as applied to aircraft. In designing radio apparatus for airships and aeroplanes due consideration must be given to the extremely lim- ited space available on such craft, and the limited weight that can be carried. In the case of aeroplanes the guy wires and other metallic parts of the machine are generally used as the ground (the capacity ground), while the aerial is in the form of a trailing wire that is paid out from a reel after the machine has reached the proper height. Most aeroplane sets have a range of from five to thirty-five miles, and because of the intense noise and vibration of the engines it is a very difficult matter to receive messages on board ; in fact, military operations make due allowance for this condition and depend upon the aeroplane wireless operator to devote his attention almost exclusively to sending. On board airships of the Zeppelin or the flexible types it is possible to employ more powerful apparatus, hence a greater range can be covered. A typical airship installation consists of a transformer, quenched spark gap, capacity and inductance, aerial wire lowered down from a winch, ammeter, rapid-change switch for different wave-lengths, and an alternating current generator driven off one of the engines of the airship. Such a set, weighing about fifty-five pounds without the alternator, has a range between 60 and 120 miles. The aerial wire is over 600 feet long when fully paid out. Armies in the field employ portable wireless sets for insuring communication between scattered commands. Some sets for use in rugged country are arranged to be carried on mule-back, and are known as pack sets. But the most common wireless sets are those mounted on two wagons, one for the generating equipment and the other for the wireless apparatus proper. The aerial of these sets is arranged in the form of an umbrella, spreading out in all directions from a common pole. The latter is usually of aluminum or an alloy of that metal, made up of a number of sections which can be readily coupled together. Within five minutes a mast of this kind can be erected, together with the aerial and the counterpoise or capacity ground. Still another form of portable military set is the automobile truck set, which is carried as one unit on a powerful motor truck, and has a range of well over one hundred miles under favorable conditions. demonstrate the value of long-distance wireless stations for maintaining communication between widely separated countries. Germany has set a mark in the art by maintaining telegraphic communication with neutral countries after finding herself surrounded by enemies on all sides and isolated from the outside world. Through the wireless station at Nauen, near Berlin, the German authorities have been able to give each day to the neutral world the news of the war from the Teuton point of view, without danger of the news being censored or altered in any way by enemy powers. Much of the telegraphic traffic between Germany and the United States during the war has been handled through the Nauen and Eilvese stations in Germany, and the Tuckerton and States. The Allied powers too, although not isolated from the outside world, have made good use of wireless telegraphy in keeping in touch with each other and in maintaining communications between their scattered armies throughout the globe. It is understood that the Allies in the West and Russia have kept in touch by wireless telegraphy, the Eiffel tower having been used in the West, and a powerful station at Petrograd, for the purpose. Wireless has also been employed to an unprecedented degree in keeping in touch with warcraft of all kinds, even to the submarine boats fitted with folding masts that can be hastily erected to support an aerial when the craft are on the surface. Upon the completion of the European War a great chain of wireless stations encircling the globe will be put into operation. It is not unlikely that these stations may soon prove a formidable competitor to the cables, although it is doubtful if they can ever be more than a supplement to the older form of inter-continental communication. Many of the worldencircling wireless stations represent the very latest phase of the art, with ranges of thousands of miles, and arranged to receive and transmit messages simultaneously and without interference. the collection and distribution of weather information to seamen and others, which service is of great value to all mankind. Wireless has also been applied with success to the problems of higher surveying, particularly by the French in the Sahara and on the Congo in Africa, and by Capt. Edwards on the boundary between Brazil and Bolivia. A careful comparison of time between distant points has also been rendered possible by wireless, which, because of the high velocity at which the electromagnetic waves travel, can be considered as being practically an instantaneous means of communication for such distances as are encountered on this earth. Or it may be due to the romance of picture making — the story in back of the screen story, which so often excels the tale of the film in point of human interest. But whatever may be the reason, the fact stands that no modern industry commands as great interest among the multitudes as motion pic- From a purely mechanical point of view, motion pictures are nothing more than a number of photographs of any one object or group of objects taken at frequent intervals on a strip of film. The exposures are made at the rate of sixteen per second ; and each picture — a photo- graph as perfect as the best of lenses and the highest photographic skill can produce — measures but one inch in width by three-quarters inch in height. Perforations are provided along either edge of the film, with which the mechanism of the camera engages for the purpose of intermittently drawing the celluloid strip through the rays of light coming in through the lens, the object being to move the film a trifle over threequarters of an inch each time an exposure has been made, so as to bring a fresh section of film in the path of the light rays. The film that is exposed in the camera is generally a negative. It is developed in much the same manner as an amateur film, although its great length calls for the employment of a rack or a drum on which to wind it in order to facilitate handling. The negative developed and dried, it is passed through a printing machine together with fresh unexposed positive stock so as to make as many positive prints as may be required. It is the positive print of any motion picture production that is passed through the projecting machines in theaters and viewed on the screen by the millions. But let us look in back of the screen : let us glance into the activities of those who make the film productions possible, but who always remain unknown to the audience, while the actors who perform no greater part in the work become famous. The audience is tense with excitement as the hero in the film play struggles frantically with the control apparatus of a submarine that is fast sinking to the ocean bottom, because of the constantly rising water in its hold. And as he struggles at his post the water pours in on him through an ugly gash made in the conning tower of the craft by an enemy destroyer. Perhaps it is the climax in a gripping drama. then again, it may be the big scene or "punch" in a hilarious comedy. But, however that may be, the realism of the scene has the desired effect on the audience. What dangers these motion picture folk incur in their daily work ! is the general comment of the unsuspecting public. Several months ago the scene in question was acted, not, as might be supposed, in the interior of a submarine, but in a quiet corner of a motion picture studio. The "submarine" was an elaborate structure of wood, metal, and plenty of paint ; life-sized to be sure, but only of a sufficient length or depth to represent the particular compartment portrayed in the picture story. For weeks the artisans of the studio workshops had worked in building this pseudo submarine ; and before the camera crank was turned the technical director had gone over every detail of its construction to make sure that it emulated successfully the interior of a modern submarine. Then the studio hands built a tank around the scenery. The "set," as the scenery for a studio scene is called, was now ready for the director. The director, being unable to carry out his programme of photographing certain outdoor or "location" scenes on a certain day because of rain or poor light, decided to stay at the studio and photograph the interior scenes called for in the scenario or working plan of his picture. At the command of the director one of the stage hands climbed up on the deck of the "submarine," pulling a heavy hose after him, which he placed in the opening of the conning tower. The water was turned on, and it flowed through the hose and passed down upon the back of the actor playing the part of the hero-sailor struggling with the control mechanism of a balky underwater craft. MOTION PICTURES IN THE MAKING The water, bounded on all sides by the improvised tank of wood and rubberized canvas, slowly rose in the "submarine" interior. The camera, which all the while was recording the action, was naturally so focused as to take in only the desired portion of the setting — the sides of the tank did not show in the film. The scene was a success. Typical of the striving of all the foregoing instance. A half dozen years ago the audience of the average picture theater was not as critical as the audience of to-day. Formerly a director depended solely upon a good story and fair acting to make a film production a success; whereas to-day the director strives to reinforce these two essen- No motion picture studio would be complete without its carpenter shop and staff of expert workmen. There are so many things that must be built especially for the pictures that a complete equipment of woodworking and metalworking machines and a skilled gathering of artisans are an absolute necessity. It would be impossible to describe with any pretense to thoroughness the range of work turned out by the studio workshops. It is only by offering a few examples of what they do regularly that a general idea of the scope of their toil can be BACKGROUNDS MADE TO ORDER TO FIT THE FILM STORIES (1) A set representing the living room of a country home. Note how the stairway at the left terminates in a wooden platform, beyond the range of the camera. In this Thanhouscr set; (2) A set representing an office. The players at the left do not appear in tho Gaumont film being produced, for they are out of the range of the camera. tials with the utmost realism of scenery. It is imperative, claim the producers, that the pictures be replete with realism ; the audience must not be permitted to recall the fact that after all the scenes in many instances are but improvised backgrounds and the necessary pieces of furniture taken from the stock room or property room of the studio. In brief, the audience must be made to forget the mechanical end of picture production; and to this end every effort is made to gained. One day they may be building a safe of light wood or compressed paper — accurately made even to the bolt mechanism — which may bring forth roars of laughter from an audience months hence, when it is dropped on the head of one of the comedians in a film play. They may be called upon to build an aeroplane, closely following the lines of a genuine machine that is to be used in the scenes of actual flying. The workmen may perhaps put in one or two weeks' work in building the aeroplane, exercising much ingenuity in its construction. As likely as not the tires of the landing gear may be made from short lengths of rubber hose or canvas tube, filled with sawdust. And the same degree of ingenuity may be repeated a dozen times or more in the construction of the machine ; all, this work to appear for a few seconds on the screen, and probably doomed to be blown to pieces or burned to ashes. The men may turn to the construction of a mirth-provoking hose-cart or fire-wagon for the fire department of some imaginary rural community. Again, historical or period plays may keep the artisans busy building a replica of the first steamboat, or making an old stage-coach, or a Roman gladiator's weapons and shield, or even an ancient catapult. All these things are in the day's work. In a recent war play, "The Fall of a Nation," four huge siege guns figured conspicuously in the battle scenes between defenders and invaders. Each gun was a faithful reproduction of the famous Krupp 28-millimeter siege howitzers, mounted on caterpillar wheels. When seen on the screen, even a military expert would be apt to mistake the guns for their counterparts busily engaged on European battlefields. As a matter of fact, however, these "guns" were made of wood, and at the time represented perhaps one of the most intricate pieces of work yet undertaken by the film artisans. They were a faithful copy of the actual pieces, even down to the recoil cylinders which actually functioned following the explosion of a charge of black powder in the metallined barrel. The guns were said to have cost the producers of the film some $10,000 each, and although the amount appears rather high at first, nevertheless it serves to accentuate the great amount of preliminary research work and designing that had to be carried out before the actual construction began. And here again the producers insisted that if the guns were to be used at all, they must be accurate enough to pass before the most critical audience without arousing undue suspicions. The producer of a submarine story, which, in its main essentials, closely follows the theme of Jules Verne's "Twenty Thousand Leagues Under the Sea," recently endeavored to secure the loan of a United States submarine from the Navy Department, without success, so the story goes. Whereupon he set out to build a submarine of sheet iron, with a length of over 100 feet, a beam of 15 feet, and a draft of 4 feet. The shell had to be of sufficient strength to withstand a submergence of forty feet deep. By means of tanks the submarine could take on water in order to settle down beneath the waves, while compressed air tanks permitted of blowing out the water ballast when the craft was to be brought up to the surface again. The submarine was fitted with a torpedo tube capable of discharging a regulation torpedo. In all, six months' time was expended in building this submarine, which closely followed the lines of the "Nautilus," the famous craft of Captain Nemo : indeed, the Navy submarines were hardly suitable to represent the fictitious craft, which may have been one reason why the producer decided to construct a special submersible, fitted with a lock in its bottom through which divers wearing self-contained suits could pass out to the ocean floor. World and the Woman," there was to be a garden scene during a thunder storm. One of the features of the scene was a driving rain, while another was a flash of lightning. The scenario called for these things : there was nothing for the studio artisans to do but to produce the desired effect. An aeroplane p r o p e 1 1 e i was mounted on a substantial support, and to it was applied the power of an electric motor through belting. An artificial garden set was soon arranged and housed in a suitable shelter to make it dark — the photographing took place in the yard of the studio, in the middle of a beautiful day. Above the set was arranged a trough, perforated with many holes to allow water to drop below on the scenery. When everything was ready, the electric motor was started, causing the aeroplane propeller to blow up a veritable hurricane through the set. Stage hands with watering cans began to pour water into the trough, which fell in the form of rain only to be driven at an angle across the setting, simulating a powerful gale. And at the propitious moment another stage hand set off a flashlight, giving the desired flash-of-lightning effect on the film. All of which bespeaks well of the skill of the artisans of the screen. Most of their work is done in wood and canvas, although occasionally they resort to metal, as witness the submarine already mentioned. Papier mache', plaster of Paris, compressed fiber and clay are also used in profusion, especially in the making of statues, ornate panels, and other work of a similar nature, forming part of elaborate sets. working shop and machine shop combined. A typical comedy-producing studio in southern California, for instance, has over $2,000 worth of woodworking equipment in its carpenter shop, while the stock of lumber constantly on hand and other items are said to bring the total up to $4,000. The concern employs regularly over seventy-five carpenters. BUILDING INTERIORS TO FIT THE STORY The interior settings of a film play require the closest attention on the part of the producers. For here again the constant demand for accuracy and realism is paramount. The smallest details must be watched. If the director calls for a tenement house scene, the stage carpenters must build him a dilapidated hall and stairs, and small, squalid rooms. The scene must appear much the worse from wear and old age — the steps must look worn; the walls must be marred, with here and there a hole in the plaster ; and there must be dirt a-plenty. Again, if the director calls for the home of a rich man, it is necessary that he state what kind of rich man the film author had in mind. Is he a wealthy man from a family of long BRAINS AND SKILL AT WORK IN THE MOTION PICTURE STUDIO At the left: The technical director of the Vitagraph studio supervising the arrangement of the furnishings in an elaborate set. At the right: Film artisans at work, making the various objects required In Vitagraph picturee. standing, or is he a nouveau richef If he belong to the former class, the furnishings are to be of a quiet, harmonious design, with the paintings and other ornamentation typifying good taste ; while if he belong to the latter, the furnishings must be of a garish sort. For it is in this manner that the motion picture producer endeavors to amplify the type of man whose home is represented. And motion picture traditions have it that a man with newlyacquired wealth must have garish tastes, and that a tenement house must always be old, dirty, and much the worse from excessive wear. In other words, exaggeration is practiced in order to leave little to the imagination of the audience. Obviously, it would not do to leave the selection of furnishings and their proper arrangement to stage hands and carpenters, and accordingly the demand for accuracy and realism has brought into existence a new type of executive in the film industry — the technical director, or art director as he is sometimes called. To him falls the task of reading through the synopsis or scenario of a film story, followed by the supervision of the erection of sets. He is responsible for the arrangement of the furnishings, even down to the smallest details, as well as for the costuming of the players. However, he is not responsible for the action part of a scene ; that task remains, as ever, the work of the director. The technical director must be a veritable human encyclopaedia — a man of remarkably broad knowledge and experience. He must be well read ; and what he does not know he must be able to "dig up" at short notice. Here is how his knowledge and experience are applied : If a scene is laid in a certain country and the time is of a different century, he must know what garments the players are to wear, the accouterments of the soldiers, the etiquette of the period and country, Perhaps actual incidents are most convincing in illustrating how the directors strive for accuracy, and how the absence of technical direction may be fatal to an otherwise perfect production. The story is told of how Irvin Cobb, the noted American writer, was visiting a prominent Los Angeles studio while a director was rehearsing a scene of a war play in which a regiment of German soldiers were marching through a Belgian village. To add what he considered a touch of comfort and naturalness to the scene, the director had the men leave their coats unbuttoned. Mr. Cobb, then only recently returned from the war zone, was horrified at this gross misrepresentation of facts. He did not hesitate to tell the director that at no time do the Germans have their coats unbuttoned while actually on the march or on duty. The director was grateful for the tip, for he realized the humiliation that might have been his if the otherwise perfect scene were held up to ridicule by the better-informed of the millions who would ultimately view the picture. At the same time the author also commented on the wearing of the Iron Cross decoration, which the director had insisted the men should waar conspicuously, whereas it is actually tucked away with only its ribbon showing. Can there be any doubt of the necessity of a technical director? To return to interior settings : These represent one of the big items of expense in the production of a film. One reason is that the average set can be used in one production only, after which it must DC dismantled. In the earlier days the audience might not have commented on seeing the same pieces of furniture used several times. But to-day the audience is more observing and will soon detect any attempt to use the same lamp, settee, or other fur- nishings repeatedly. Conspicuous repetition has got to be avoided by the producers. And as in the instance of the garments worn by the players, the furniture must be in keeping with the last word in interior furnishings. So every studio maintains a large room or several rooms in which an almost endless variety of furnishings is stored. or light board, backed up with framework and props, to facilitate the work of erection and destruction. Tremendous quantities of the necessary materials are employed in the course of a year, as witness some 50,000 feet or more of compressed paper board used by a leading comedy producer, together with over 500,000 feet of lumber. The same concern spends over $1,800 for some 15,000 rolls of wall paper each year, with which to cover the walls of its sets. The cost of even the most modest set runs up into the hundreds of dollars, for it must be remembered that practically every set must be built and decorated to order, and filled with the necessary furniture, which may not be used for a long time to come. Elaborate sets run up into the thousands of dollars. A good restaurant or cabaret scene may cost from $2,000 to $5,000, depending upon its elaborateness and size. A setting calling for intricate electric lighting effects sometimes exceeds the $5,000 mark, for instance, the witches' scene in the recent production of "Macbeth," starring Sir Herbert Beerbohm Tree, which is said to have cost over $10,000 because of the elaborate apparatus for producing the weird fire effects. STRUCTURES The film artisan finds his biggest field of endeavor in the outdoor sets, for under the open skies his undertakings are not hindered by space limitations and can therefore as- sume the most gigantic proportions. Here again, the striving for realism is the first consideration; here the technical director must exercise his knowledge of architectural design covering every period in history and every part of the world. Perhaps the greatest set that has ever been constructed up until the time of writing was one representing the ancient city of Babylon, employed in the gigantic production "Intolerance." On the front of this huge setting — the side that faced the camera — there rose high walls painted to simulate stone, 100 feet in height and adorned with reliefs of strange winged creatures and elephants. The towers of the set stood 135 feet high, and the various structures covered a ten-acre tract of land in Hollywood, CaL, just outside of Los Angeles. For more than six months the carpenters, masons, concrete workers and painters were busied with the set, and the cost of the work is reported to have been in excess of $50,000. But slightly less pretentious was the set erected at an approximate cost of $35,000, representing the palace, house of parliament, prison, royal court, and adjacent buildings in a mythical coiintry featured in the production "Civilization." The first spadeful of earth in preparation for the erection of the set was turned in May, 1915. The completed set was ready for use in November of the same year. Into its construction went thirty carloads, or approximately 600,000 feet, of lumber. Glass valued at a total of $4,000 was necessary for the several hundred windows, while tons upon tons of cement and plaster were used as the other principal materials. For the steps of the largest building alone ten tons of cement was used. The sidewalks, with their curbings, measured some 1,200 feet, and twenty men were employed for three months laying them out and arranging the parkings between them. Trees, the ornaments placed within the boundaries of the set. Covering an area of over six and one half acres, the set has stood atop one of the hills in southern California, enduring the elements successfully as though it were intended as a permanent structure. It is principally in portraying foreign scenes that the film artisans are called upon to build elaborate sets. Years ago, before the industry had reached its present high standard, companies traveled abroad in order to produce plays at the actual locations called for by the scenario. To-day, in marked contrast, the producers find it easier to bring the foreign or distant spots to the studio, literally speaking. Accuracy enables them to convince the audience that the scenes have been laid in the country called for by the story. All parts of the world have been brought to the foothills of California, the shores of Florida, and the edge of the Palisades of New skylight. Jersey, where the producers have better laboratory facilities, understand the light conditions, can secure experienced players — and save time. Typical instances of foreign sets have been the barracks of Delhi, India, and a street in a village of a mythical country, recently erected and used by a Western producer. The former consisted of seven individual structures and entailed an expenditure of $3,000; the latter represented a street lined with houses of solid construction. The houses were made of plaster-covered timbers, while the stone walls and trees were handled with great care to obtain correctness of detail. The entire set required about six weeks to build and involved an outlay of perhaps $5,000. There is practically no end to the elaborate outdoor sets erected by motion picture producers. In the production of "Ramona" it was said that over 1,800 sets were especially built for the play, and that the picturesque Spanish monastery for one of the sets cost some $10,000. A commendable piece of work was the set representing the temple of an Aztec monarch in the sixteenth century, which was used in the production "The Captive God." Its framework was built of timbers, but the body was of plaster plaques. About 7,000 of these plaques were required ; and the total cost of the set is said to have been $3,000. A set representing a border town on the line separating Mexico from the United States, for use in a typical Western drama, was recently constructed at a cost of $1,500. It consisted of fifteen buildings, each entirely of frame construction. While the cost of the village was not great, at the time it was regarded by film men as one of the most realistic sets ever built for the screen. Thousands of other sets might be described, for they come and go without end. But enough instances have been cited to prove that the production of motion pictures is a costly enterprise if realism is to be secured. Also, there is to be found no more skilled and ingenious artisan than the artisan of the screen, whose work, generally unappre- of various remarkable physical phenomena. Considered especially with reference to their biological, and above all their human, relations, the activities of the atmosphere are known collectively as iceather ; but the study of the atmos- orology, is broader than the study of weather. Hence, if weather is important, and everybody knows that it is immensely so, in terms of health, comfort and dollars, meteorology is still more important. This science ought to be, but is not yet, represented by professorships in every university in the land. ATMOSPHERE The lower part of the atmosphere is the densest because it is compressed by the weight of. the air above it. Thus it happens that, although the total depth of the atmosphere is probably at least 300 miles, one-half of its mass., i.e., onehalf of the quantity of matter in it, lies below an altitude of about three and one-half miles above sea-level, while about seven-eighths lies below tho ten-mile level. Above about five miles the atmosphere is too rare (or rather the oxygen in it is too rare) to support life. The highest iceclouds seldom occur higher than ten miles. Storms hardly ever reach this height. In short, the phenomena of life and the phenomena of weather are confined to a layer of air so shallow, in proportion to the dimensions of our globe, that on the surface of an orange it would be represented by a sheet of paper thinner than the average book-paper. Dry air is a mixture (not a chemical compound) of several gases, viz., about 78 per cent nitrogen, 21 per cent oxygen, 1 per cent argon, and 0.03 per cent carbon dioxide, by volume, besides minute quantities of hydrogen, neon, krypton, xenon, helium and possibly other substances. At levels habitable by man the air always contains invisible water vapor (from a small trace to about 5 per cent), and usually small and variable amounts of ozone, ammonia, nitric acid, and other gases, which, on account of their irregular occurrence, are not classed among the normal constituents of the atmosphere. Lastly, the lower air always contains solid impurities, in endless variety, generically known as dust. extend farther upward than the heavier. Probably there is no water vapor above about 12 miles ; no oxygen above about 60 miles, and no nitrogen above about 70 miles. From a level of about 50 miles upward the atmosphere, instead of being "air," is mostly hydrogen — the lightest known gas. Moreover, at the 50mile level the atmosphere is less than 1/75,000 as dense as at sealevel; i. e., it is more than seventyfive times as attenuated as the best "vacuum" obtainable with an ordinary mechanical air pump. At 300 miles above the earth it is computed to be about one-two-millionth as dense as at sea-level. Ozone, which occurs transiently and in small amounts in the lower atmosphere, is believed to be permanently present and abundant at high levels, where it is formed from oxygen, probably under the influence of ultra-violet The past twenty years have witnessed a remarkable development of upper-air research, or aerology. Up to a height of about four miles the atmosphere has been extensively explored by means of self-registering meteorological instruments (meteorographs) attached to kites — not of the schoolboy pattern, but box or cellular kites, the "string" of which consists of several miles of steel wire, wound around the drum of a power-driven winch. Captive balloons have also been utilized to some extent. For attaining great altitudes, however, free balloons must be used. The so-called sounding- SOUNDING THE UPPER AIR Left: Launching a pair of sounding balloons, with self-registering meteorological instruments attached. Upper right: Balloon meteorograph and the protective cage in which it is sent aloft. Lower right: Weather Bureau party making upper air observations. light from the sun and of auroral discharges. The existence in the atmosphere of a gas unknown to chemists and li'ghter than hydrogen has been maintained in some quarters (especially by Dr. Alfred Wegener), and it has been named "geocoronium," or "zodiacon." If present at all, it is presumably the chief constituent of the atmosphere in the upper levels. balloon, which carries a meteorograph, bursts far above the earth, and the attached instruments are carried gently down" by a parachute, or an auxiliary balloon. Soundingballoons rise to various heights up to 20 miles. Small balloons sent up without a meteorograph attached, merely for the sake of observing the drift of the air at various levels, are thus been attained. Since the year 1902 it has been known that the atmosphere is divided into at least two layers, or shells, having quite different characteristics. If from some place in middle latitudes we could travel in a balloon as far upward as we pleased, carrying a thermometer with us, we should find the air rapidly growing colder, at a more or less uniform rate, as we ascended until we reached an altitude of about seven miles. Then the fall in temperature would abruptly cease, and might even be succeeded by a slightly rising temperature for a certain distance upward. This would indicate that we had passed out of the troposphere, as the lower stratum of the atmosphere is now called, and entered the stratosphere, or isothermal layer, in which there are no very decided or regular changes of temperature with altitude. The boundary between the two layers lies much higher in equatorial regions, and the temperatures at the summit of the troposphere in such regions are lower than anywhere AEROLOGICAL OBSERVATORY else in the atmosphere. A soundingballoon over Batavia, Java, has recorded 133 degrees below zero, Fahr., at an altitude of about ten miles. Besides differing from the tropo- sphere in its lack of regular temperature contrasts in a vertical direction, the stratosphere has an independent circulation ; concerning which, however, not much is yet positively known. THE PBESSTJBE OF THE ATMOSPHERE The atmosphere presses down upon the earth with a weight which, at sea-level, amounts, on an average, to 14.7 pounds to the square inch. This pressure is, at any point, exerted equally in all directions; it acts, for example, on the whole surface of the human body, and this means that a man of average size lives under a burden of some seventeen tons of air. He is not incommoded because the pressure from without is balanced by that of the air inside his body. The pressure of the air decreases upward at the same rate as its density ; at an altitude of three and one-half miles it is about half as great as at sea-level. Thus the atmospheric pressure on mountains and plateaus is considerably less than in lowlands. At no place is the pressure invariable, nor is there a constant relation between pressure and altitude; but, knowing approximately the average atmospheric pressure over the earth's surface, and knowing also the area of the latter, we can compute in round numbers the total weight of the atmosphere— about 5,000,000,000,000,000 (5 quadrillion, according to American notation ; 5,000 billion, according to British notation) tons. This is about 1/1,200,000 of the entire weight of the terrestrial globe. ured by means of an instrument called the barometer, and hence is often referred to as "barometric" pressure. In this instrument the weight of the air is balanced against a column of mercury, and the height of the latter, generally expressed in inches or millimeters, is taken as the measure of the former. Hence, when we say that the average barometric pressure at sea-level is 29.92 "inches," we are really expressing HOW THE ATMOSPHERE IS HEATED Our life and our weather are both maintained by a tiny fraction — less than half a millionth — of the heat given off by the great luminary around which the earth revolves in space. At any given moment half the surface of the globe basks in the sunshine while the other half is in shadow. Besides rotating on its B, winter in N. hemisphere and summer in S. hemisphere ; D, summer in N. hemisphere, winter in S. hemisphere ; A, C, equinoxes. axis once a day, the earth revolves around the sun once a year, and its axis, which always remains parallel to itself, is inclined to the plane of its orbit. These facts (illustrated in the accompanying diagram) explain the alternation of day and night, the march of the seasons, and the opposition of the latter in the two hemispheres. The northern half of the globe receives more than its share of solar heat at the season when the southern half is receiving less, and vice versa; hence the northern summer coincides with the southern winter, and the northern winter with the southern summer. The amount of heat received at a particular place, at a given time, depends chiefly upon the angle at which the sun's rays reach the changing. The interposition of clouds, variations in surface topography, different heat-absorbing properties of water and land, and a number of other complications accentuate still further the contrasts in temperature between different parts of the earth's surface, and these contrasts give rise to the winds. Some of the heat that comes to us from the sun is absorbed in its passage through the atmosphere, but the greater part of it penetrates to the earth, where it is absorbed, and then given out to the lower strata of air. Thus our atmosphere is heated chiefly from below. The air that is heated at the earth's surface expands in all directions, but especially upward, where it encounters the least resistance. Moreover, air that has risen and spread out laterally increases the pressure on the air over which it has flowed, and this lower air pushes in toward the over-heated area. The inflowing cooler air helps to drive the heated air upward. In other words, the heated air does not rise merely on account of its expansion, but because it is pushed up by the air around it. Philosophically speaking, our atmosphere is kept in motion by solar energy, just as a steam-engine is kept in motion by the energy of fuel. Since the atmosphere is relatively very shallow, the distances the air rises and falls under the effects of temperature are extremely small compared with the distances it is> carried over the surface of the earth. It is chiefly the horizontal movement of the air that we think of as "wind," but the up-and-down movement is an essential part of the process and has several important effects. THE GENERAL WIND OF THE GLOBE In the equatorial regions the surrace air is heated more than elsewhere, and rises and overflows, at high levels, toward the poles ; while the relatively cold air of high latitudes flows equatorward, near the earth's surface, to replace it. A simple circulation between the equator and the poles could, however, only occur if the earth did not ro- THE REALM OF THE AIR tate on its axis. The "deflective force" of the earth's rotation causes a particle of air moving in any direction over the earth's surface to deviate — to the right in the northern hemisphere and to the left in the southern (a phenomenon that is not limited to air movements, but applies in general to bodies moving freely over the earth). At about latitude 30 degrees the winds coming from the equator have been so much deflected that they move almost eastwardly. The result is a great whirl around the pole, occupying most of the temperate zone in each hemisphere, with prevailing winds from the western quadrant at all levels. The centrifugal force of this whirl causes the air to bank up at about latitude 30 degrees, producing a belt of high pressure in that region, which is sometimes known as the horse latitudes. Between this belt and the equator there is a regular circulation of air e q u a to r w a r d below ( the trade icinds) and poleward above (the anti-trades) ; and both these systems of winds are given an oblique direction by the earth's rotation. Near the equator, between the two tradewind systems, is a region of calms and variable winds, with abundant clouds and rain, known as the doldrums. Trades and doldrums shift alternately north and south in the course of the year, following the sun, and give to regions which come under their control, successive dry and raint/ seasons. Within the polar circles the low temperatures increase the density of the air, which flows away from the poles near the earth's surface; an effect that appears to be strengthened by the drainage of air down the glacier slopes of the two polar continents (Greenland and Antarctica). The accompanying table shows in a general way the arrangement of the principal wind-belts of the earth. This represents prevailing conditions, which are, however, subject to many interruptions. In middle latitudes, for example, while the prevailing drift of the air is eastwardly, the actual wind at any place and time is usually determined by the positions of cyclones and anticyclones (of which we shall say more SOUTH POLE presently). Any of these general wind-systems may be disturbed by the seasonal winds known as monsoons, which blow outward from a continent to the ocean in winter and in the reverse direction in summer. Interruptions on a smaller scale arise from a day-and-night alternation of winds to and from bodies of water (land and sea breezes; land and lake breezes), and a similar daily reversal of the wind direction in mountainous regions (mountain and valley breezes). areas of low and high barometric pressure, respectively, exhibiting certain typical conditions of wind and weather. In this country the term "cyclone" is persistently misapplied by the hands of a clock) around the center ; not in circles, but more or less spirally inward. In the southern hemisphere their direction is reversed. The anticyclone has a circulation opposite to that of the cyclone (clockwise in the northern hemisphere and counterclockwise in the southern). There are certain regions of the globe in which cyclones or anticyclones of large extent (known as "centers of action") tend to persist through a season or the whole year, though with fluctuations in size and activity. Most cyclones and anti- by the newspapers and the public to a very small intensely violent storm of the "spout" variety, properly known as the tornado. The true cyclone covers an area thousands of times as great as that covered by a tornado, and its winds may be either stormy or gentle. In the northern hemisphere the winds of a cyclone blow "counterclockwise" (opposite to the direction followed cyclones, however, travel over the earth, and those of the temperate zone (the "lows" and "highs" of the weather map) move in a general west-to-east direction. In the United States their speed averages about 600 miles a day. (This refers to the translation of the whirl as a whole, and not to the force of its winds.) In general, cyclones are attended by clouds and rain or snow; A FREAK OF THE TORNADO anticyclones by fair weather. The temperature commonly rises with the approach of a cyclone, and falls in its rear. It is the constant passage of cyclones and anticyclones over the country that gives us our changeable weather. On the weather map these areas are depicted by drawing lines, called isobars, connecting places having the same barometric pressure. Wherever the isobars are crowded the winds the strong; where they are widely spaced the winds are gentle. The tropical cyclone (hurricane of the West Indies, typhoon of the China Sea, baguio of the Philippines) is a relatively violent whirl, .which originates in the stagnant air of the doldrums, and usually moves in an oblique and curved path toward higher latitudes, frequently passing into the temperate zone, where it increases in size and decreases in strength. While middle-latitude cyclones occur throughout the year, tropical cyclones are almost limited to particular seasons (those of the West Indies are commonest from July to October), and they are also confined to rather small regions of the globe. Storms of this type cause frightful devastation in the Caribbean Sea and the Gulf of Mexico, and occasionally in the southeastern United States (as at Galveston, September 8, 1900, when 6,000 lives and $30,000,000 in property were destroyed, chiefly by the great waves generated by the storm). TORNADOES AND THUNDERSTORMS The tornado is a small vortex In the atmosphere, occurring generally in the southeastern part of a cyclone, and rarely experienced, in its full development, elsewhere than in the United States, east of the Rocky Mountains. Its average diameter is about 1,000 feet, and it travels along a path varying in length from a few hundred yards to 200 or 300 miles. The whirl as a whole moves at a speed averaging 25 miles an hour, while the velocity of rotation probably sometimes amounts to 500 miles an hour — a wind-force far exceeding that of any other type of storm. Within the narrow track of the disturbance buildings are blown to bits, trees are uprooted, and human beings only find safety underground; but close on either side of the track little or no damage is done. The position of the whirl is marked by a funnel-shaped cloud. Waterspouts, which occur on the ocean and other large bodies of water, are similar in character to tornadoes, though generally very much less violent. Thunderstorms occur chiefly in warm climates and during the warm season in temperate climates, but they are by no means unknown in the polar regions. They are characterized by rapidly rising air currents, which may be either incidental to the circulation of a cyclone or due to local overheating of the ground under strong sunshine. Cyclonic thunderstorms sometimes occur along a line several hundred miles in length, extending radially from the center of a cyclone, and sweeping over the country at a fairly uniform speed. This phenomenon is called a line-squall. The electrical features of a thunderstorm are the result and not the cause of the atmospheric movements. The process by which the clouds become so strongly electrified as to give rise to disruptive discharges between cloud and earth, or cloud and cloud, is not yet settled beyond controversy, but has been plausibly ascribed to the breaking up of raindrops in uprushing air currents, and the consequent separation of positive from negative electricity. Lightning owes its luminosity to the heating of the air along the path of the electrical discharge. The sudden expansion of the heated air produces the sound-wave we call thunder. A flash of lightning sometimes consists of a single virtually instantaneous discharge; but in other cases several discharges occur in rapid succession along the same path, giving to the lightning a flickering appearance. The duration of a multiple flash of this character may amount to half a second or more. When such a flash is photographed with a camera swinging on a vertical axis, the successive flashes appear side by side on the plate. The rare form of discharge known as pearl or beaded lightning presents the appearance of a string of luminous beads. Still rarer is rocket lightning, which shoots up into the air at the apparent speed of a skyrocket. Ball lightning, which takes the form of a globe of fire moving slowly through the air near the earth (sometimes indoors) has not yet been satisfactorily explained. Heat lightning is the reflection on the clouds of ordinary lightning too distant to be audible. Lightning is far more destructive in the rural districts than in cities and towns. In this country the average annual property loss from this cause is about $8,000,000, while about 1,500 persons are affected annually by lightning stroke, one-third of this number being killed. The efficacy of well-constructed lightning-rods is not doubted by competent authorities. Statistics show that they reduce the fire hazard from lightning by 80 to 90 per cent in the case of houses, and by as much as 99 per cent in the case of barns. OTHER ELECTRICAL PHENOMENA St. Elmo's fire (also known under a score of other names) is a brush discharge from the points of terrestrial objects, and is most common on mountains. It is also seen on the masts and spars of vessels. Brush discharges on a vast scale are said to occur along the crest of the Chilean Andes, whence they are visible hundreds of miles out at sea. The aurora (called aurora, 'borealls in the northern hemisphere and aurora australis in the southern) is now most commonly attributed to the passage of cathode rays through the atmosphere, under the effects of some kind of radiation or emission from the sun. It is especially common and brilliant at times when sunspots are numerous, and is accompanied by disturbances in the earth's magnetism. The aurora has been carefully studied in high latitudes by means of simultaneous photographs from two stations, whereby its altitude and distance from the place of observation can be determined. There appear to be two principal forms : viz., a tranquil, homogeneous arc, occurring only at great altitudes, and shifting beams and "draperies," occurring mainly at lower levels. There is some evidence that a feeble auroral glowr commonly extends over the whole nocturnal sky, in all latitudes (carthlight). gion toward a cyclonic center is called, in southern Europe, a sirocco, and this term is sometimes applied to similar winds elsewhere. Such winds are commonly associated with the heated terms or "hot waves" of our American summers. Winds blowing in winter from regions of high barometric pressure and low temperature bring us cold waves and sometimes blizzards (the latter term implying the presence of driving snow in addition to high wind and low temperature). The northers of Texas come under this head. mountains, and which is further dried and heated in descending the leeward slope. (The heating is due to the "adiabatic" process, an explanation of which will be found in physical and meteorological textbooks.) In the western Fnited States such a wind is called a chinook. Its effects are most pronounced in winter, when it brings about a very sudden rise in temperature and causes snow to vanish as if by magic, whence it has been nicknamed the "snow-eater." The bora of the Adriatic and the mistral of the French Riviera differ from the fochn in the fact that they blow from a cold mountainous interior to a warm coastland, and, therefore, though heated in their descent, produce the impression of a cold wind. Types of wind, the world over, are not numerous; but as the local examples of a given type were named before their generic identity was recognized the number of wind names in use amounts to several hundred. The khamsin, harmnttfin, simoon, leveche, leste, levanter, 1><i»tiH'ro, sonda, buran, purga, brickjteMer, southerly burster, irilliu-air, punt lux. ti ratio, ora, etc., are a few of these locally named winds. For a given temperature of the air there is a maximum amount of moisture that can be present in an invisible form (water vapor). When the air is charged to the limit it is said to be "saturated." Absolute humidity is the weight of water vapor present, per unit volume, or the tension of this vapor; relative humidity, the ratio of the amount present to the amount necessary for saturation, expressed in percentage. Cooling of saturated air causes condensation, in the form of cloud, fog, mist, rain, snow, hail, dew or hoarfrost. The temperature at which condensation occurs is called the dew-point, and this varies with the humidity. ING CLOUDINESS The highest clouds consist of ice needles, and present a feathery appearance. Fleecy-looking clouds are composed of little droplets of water. According to the International Cloud Classification there are ten principal forms of cloud; viz., three feathery forms, cirrus, cirro-stratus and cirro-cumulus, and seven fleecy or homogeneous forms, alto-cumulus, alto-stratus, strato-cumtilus, nimbus, cumulus, cumulo-nimbus and stratus. A few subordinate forms are also recognized. A common type of cirrus is popularly called "mares' tails," cirro-cumulus is known as "mackerel sky," cumulus is called "w o o 1 p a c k," and cumulo-nimbus "thunder-clouds," or "thunderheads." Nimbus is the rain cloud. A cloud at the earth's surface constitutes fog. Haze is a turbid state of the atmosphere, sometimes due merely to the varying optical properties of air of different temperatures and densities, and sometimes to the presence of an unusual phenomena (photometeors) . Falling raindrops produce, by refraction and reflection, the rainbow, opposite the sun. There is usually a bright primary bow and a fainter secondary bow; and one or both may be fringed with supernumerary or spurious bows. Lunar rainbows are sometimes seen. They are, as a rule, nearly colorless, owing to feeble illumination. Water clouds produce around the sun or moon, by diffraction, a diffuse reddish ring, called the corona-. From a mountain top or a balloon a person sometimes sees his shadow cast on a bank of fog or cloud. (The shadow seems "gigantic," owing to over-estimation of its distance. ) The head is often surrounded by a glory of colored light, due to diffraction. The whole phe- amount of dust, smoke or fine water-drops. Dust-haze, or dry fog, is characteristic of dry climates and dry seasons; it is also a result of fires in forests, moors and prairies, and of volcanic eruptions. Remarkable instances of daytime darkness have sometimes been produced by exceptionally dense haze of this character. the BrocTcen. Halos are due to the refraction or reflection (or both) of light by ice crystals in the atmosphere. They may take the form of rings of definite angular size (the commonest has a radius of 22 degrees) surrounding the sun or moon ; also of rings or arcs in various other positions, and disks of light (parhelia and paraselenae; in popular Ian- guage, "sundogs" and "moondogs" ) . Some forms of halo are distinctly colored ; others are not. An excellent descriptive account of such phenomena will be found in the Not all photometeors are due to moisture. Mirage, for example, results from the refraction of light through adjacent atmospheric strata having very different densities. One form of mirage is common over hot plains and deserts in calm weather, presenting the illusive appearance of a sheet of water. warm season. It consists of ice and compact snow, generally in concentric layers. Little pellets of snow, like tiny snowballs, falling chiefly in early spring and late autumn, but also in winter, have been inappropriately named soft hail (the German name Graupel is preferable). The term sleet is applied by the United States Weather Bureau to small particles of clear ice — frozen raindrops. The British apply this term to a mixture of rain and snow. Moisture condensed from the air on cold surfaces at night (just as it is condensed on the outside of an ice-pitcher) is called dew. If the PRECIPITATION Moisture that is condensed out of the atmosphere and deposited on the earth is called precipitation. The commonest liquid form of precipitation is rain, and the commonest frozen form, snow (each flake of which is an aggregation of tiny icecrystals). Hail, properly so called, falls almost exclusively in connection with thunderstorms, and hence, in our latitudes, is limited to the is called hoarfrost. Fog drifting against terrestrial objects in cold weather sometimes leaves a rough deposit of ice, called rime. The smooth icy deposit due to rain freezing as it falls — often very destructive to tree branches, telegraph wires, and the like — is now officially termed glaze in this country, but is popularly misnamed tutes an ice storm. In connection with the subject of precipitation passing mention may be made of the widespread delusions that prevail as to the possibility of producing or preventing it artificially. It is held, on the one hand, that cannonading and other explosions cause rain, and, on the other, that the firing of cannon, bombs and rockets drives away hail. Both beliefs are unfounded. The energy involved in such explosions is insignificant in comparison with the atmospheric forces that determine the occurrence of precipitation. CLIMATE The meteorological conditions that are characteristic of a particular region constitute its climate. With respect to temperature, climates are distinguished not only as hot, cold and temperate, but also as equable and the reverse. Marine climates — i. e., those of regions exposed to winds from the ocean — have small daily and yearly ranges of temperature, while continental climates — those withdrawn from oceanic influences— are subject to great extremes of temperature. The highest temperatures are not limited to the equatorial regions, nor the lowest to the polar regions. Probably no other part of the world experiences quite such hot weather as prevails in the deserts of southern California in summer. A shade temperature of 134 deg. Fahr. has been registered at Greenland Ranch, in Death Valley. Oceanic islands in the torrid zone never have temperatures as high as those that prevail widely over the interior of the United States during "hot waves." On the other hand, the cold weather experienced in winter in our northwestern and north-central States far surpasses anything known in much western Europe. The lowest winter temperatures in the world are those that occur in north-central Siberia, where, at Verkhoyansk, an official temperature of 90 degrees below zero, Fahr., has been recorded. Rainfall, as an element of climate, includes all forms of aqueous precipitation (the frozen forms being expressed in their "water equivalent"). Measurements of rainfall refer to the depth of water that would lie upon the ground if none of it ran off, soaked in or evaporated. Annual rainfalls may be classified, especially with respect to their agricultural significance, as excessive when over 75 inches ; copious, 50-75 inches ; moderate, 25-50 inches ; light, 10-25 inches ; desert, under 10 inches. The heaviest rainfall occurs within or near the tropics (though great deserts also occur in this region). The rainiest place in the world for which we have meteorological records is Cherrapunji, a hill station in India, with an annual rainfall of about 426 inches. The heaviest mean annual rainfall in the United States (not including Alaska) is about 133 inches in Tillamook County, Oregon. The heaviest snowfall in the United States probably occurs in the high Sierra Nevada, near the border between Nevada and California. A within a generation or so is a stubborn popular delusion, which prevails more or less all over the world, and has probably prevailed in every age. The belief in the "old-fashioned winter" is an example of this delusion. More than a century ago American philosophers wrote dissertations on the changes of climate that they supposed had occurred since early colonial times. Such ideas arise chiefly from the fact that exceptional weather impresses itself more lastingly upon one's memory than normal weather. TENNYSON, who, of all the brethren of his craft, did most to poetize the facts of astronomy, speaks of the stars as "cold fires, yet with power to burn and brand his nothingness into man." Nonentity has its advantages. A sovereign remedy for the trivial worries of human life is the contemplation of the starlit sky and the realization of the infinitesimal importance of the earth and all things earthly in comparison with a boundless universe. The nightly spectacle of the stars is, however, commonly ignored. Many people look at it all their lives without really seeing it. The more conspicuous constellations ought to be as familiar to every human being with two eyes in his head as the town hall or his nextdoor neighbor's stable. They are far from being so. Most people you meet will admit frankly that the only constellation they know by sight is the Big Dipper — which, as it happens, is not a constellation at all. A knowledge of the heavens is more general in primitive and pioneer communities than in centers of civilization and culture. The pastoral tribes of Chaldea and Arabia, thirty centuries ago, were better acquainted with the stars than are modern New Yorkers and Londoners. During the South African war the English soldiers were astonished at the ease with which the colonial troops marched at night, using the compass. The relative "nothingness" of the earth and its inhabitants is chiefly a modern idea, though it was not entirely unfamiliar to the speculative philosophers of antiquity. Thanks to the brilliant labors of many astronomers — of whom Copernicus should be mentioned first of all — we now know that the world on which we live is a planet or satellite, revolving humbly around an enormously greater body, which we call the sun ; and we know that the sun, in its turn, is a rather unimportant member of a vast system of suns, or stars. The sun looks bigger than the other stars only because it is nearer to us. vey the heavens on a cloudless and moonless night, and you will probably get the impression that the number visible to the naked eye is almost infinite. This impression is, however, quite erroneous. The greatest number of stars which the unaided eye can distinguish at any one place on the earth and at any one time is hardly more than two thousand. With an opera-glass many thousands more can be seen, and this little instrument will be found an invaluable adjunct In a study of the heavens. A portable telescope with an object-glass only two inches in diameter discloses, in the entire sky, upwards of 700,000 stars. Great telescopes, such as those THE ATWOOD SPHERE FOE STUDYING THE STABS as installed at the Academy of Sciences, Chicago. The stars, down to the fifth magnitude, are represented by perforations, of different sizes, in the sheet iron sphere, through which light shines from the exterior. The sphere can be revolved by an electric motor, making the constellations rise and set. of the Lick, Yerkes and Mount Wilson Observatories, show at least two hundred million. There are undoubtedly many million more beyond the range of all telescopes on account of their prodigious distances, and there are probably many comparatively near stars that are invisible because they give little or no light. Indeed these dark stars are suspected to be much more numerous than the bright ones. One estimate makes them 4,000 times as numerous; but this is little better than a guess. The brightness of the stars, as viewed from the earth, is expressed on a scale of "magnitudes," so related to one another that an average star of one magnitude is two and one-half times as bright as one of the next lower magnitude. Of the first, or brightest, magnitude there are only twenty stars; the brightest of all being Sirius, the Dog Star. There are sixty-five stars of the second magnitude, and two hundred of the third. The faintest stars visible to the naked eye on a clear, moonless night are of the sixth magnitude. That the astronomer, without leaving our tiny earth, can measure the distances of the heavenly bodies (or at least of many of them) is neither more nor less wonderful than that the surveyor, without crossing a river, can measure the distance of a tree on the opposite bank ; though the astronomer's task requires more delicate instruments and more painstaking observations. In both cases quite a simple trigonometrical operation is involved. The surveyor gets the bearing of the tree from each end of a measured base-line; and having thus two angles and one side of a triangle, the rest is easy. In measuring the distance of the moon from the earth, the astronomer uses for a base-line the known distance between two EXTERIOR OF THE SPHERE at Greenwich and Cape Town — and gets the bearing of the moon, or rather its apparent position as projected on the far more distant background of stars, from each observatory. The difference in the direction of the moon as seen from two places on earth (generally reduced to the difference in its direction from the center and surface of the earth respectively) is known as the moon's "parallax," and gives us the moon's distance— about 239,000 miles. The sun's parallax is found in a somewhat different manner, but the process also involves the use of the distance between two places on earth as a base-line. The distance of the sun from the earth is about 93,000,000 miles. An express train would take more than 250 years to perform a journey of this length, and a cannon ball about nine years. Light, traveling at a speed of 186,000 miles a second, requires a little more than eight minutes to reach us from the sun. is, is insignificant compared with the distances of even the nearest stars. In measuring the parallax of a star terrestrial distances are far too small to serve as the base line, and accordingly the star is sighted from two opposite points in the earth's circuit about the sun, giving a base-line one hundred and eightysix million miles in length. Even so, the base-line is barely long enough to give a measurable parallax for a comparatively small number of stars, and the observations involved are among the most refined known to astronomy. Photographic methods are now employed in measuring stellar parallaxes. The distances of the stars are so great that to state them in miles would be as awkward as stating the distance from New York to Calcutta in inches. Hence a larger unit is commonly employed, known as the "light-year." This is the distance which light travels in a year, and is a little less than six trillion miles (according to the American and French meaning of the term "trillion," corresponding to the British "billion"). Another unit, more recently introduced, is the "parsec," defined as the distance at which a star's parallax is one second of arc, or 206,265 times the distance of the of one hundred parsecs our sun would be a star of the tenth magnitude. Our nearest neighbor in stellar space is a star of the southern heavens called Alpha Centauri (the brightest star in the constellation of the Centaur), its distance being 4.3 light-years. Concerning the actual dimensions of the stars we have little positive knowledge, but it is certain that some are very much larger than others, and that our sun is far from being one of the giants of the universe. To Canopus, a magnificent star of the southern skies, has recently been ascribed by some astronomers the honor of being the biggest of the stars, one estimate giving him a volume about two and one-half million times as great as that of the sun. While such figures are highly speculative, they are not improbable. What are the stars made of? Before the invention of the spectroscope there appeared to be little prospect that mankind would ever find the answer to this question. The spectroscope is an instrument which analyzes a beam of light, and furnishes certain information concerning the source from which it comes. It spreads out the light into a rainbow-colored strip, called the spectrum. If the source is a luminous gas, the light is broken up into a number of bright lines or bands. If the light, coming from a luminous solid, liquid, or dense gas, has passed through a cooler and less luminous gas, the spectrum as a whole is bright, but is crossed by dark lines or bands. In either case the positions of these lines and bands reveal the chemical composition of the gaseous material. The interpretation of the lines and bands depends upon laboratory experiments, and the spectroscope is much used by chemists in making analyses; but it is also used, in conjunction with the telescope, by astronomers, to determine the com- position, not of solid or quasi-solid bodies in the heavens, but of the gaseous envelopes or atmospheres by which these bodies are surrounded. Both our sun and the other visible stars are so hot that some or all of the substances of which they consist (apart from those which are gaseous at low temperatures) are vaporized, and form such enveloping atmospheres. The solar spectrum shows that the sun's atmosphere, and hence the sun itself, contains an abundance of calcium, iron, hydrogen, sodium, nickel, and other substances found on earth. About forty terrestrial elements are positively known to exist in the sun, and the presence of others is indicated on less certain evidence. have been examined. Some show the presence of a few, others of many elements known on earth. The differences between different stellar spectra are, apparently, not due to any radical differences in the composition of the stars themselves, but rather to the fact that their physical conditions differ, especially as to temperature, and hence they have different kinds of atmospheres. In short, the stars, the sun and the earth are probably all made of the same sort of matter. The stars are frequently described as "fixed," to distinguish them from the planets of our solar system, which, as we shall presently see, change their apparent positions in the sky more or less rapidly with respect to the stars and to one another. Actually, however, all the stars are in rapid motion through space. Our sun, for example, travels at a speed of about twelve miles a second. Many stars move much faster. At the Mount Wilson Observatory one has recently been found with a velocity of about 358 miles a second. the course of years certain stars have been observed to change their positions a little with respect to other stars. This change is known as "proper motion," and is always very gradual. The greatest proper motion known is that of a star discovered by Barnard, in 1916, which in about 180 years changes its place in the sky by an amount equal to the apparent diameter of the moon. Proper motion of a star whose distance from us is known by observations of parallax shows how fast the star is moving across the line of our vision, i. e., the line extending from our eyes to the star, but does not tell us whether, or how fast, the star is approaching or receding from us. This so-called radial motion, or motion in the line of sight; is determined by means of the spectroscope. The result of such motion is a slight displacement of the spectral lines from their normal positions. Displacement in one direction shows that the star is approaching, and in the other that it is receding; while the amount of displacement indicates the speed of approach or recession. In general the stars are so far apart that they show no definite effects of one another's attraction, but there are a number of pairs of stars which are obviously revolving around common centers of gravity. These are called "binaries." Among those thus far discovered the periods of revolution range all the way from a few hours to 1,500 years. Some of these pairs are so close that they appear as a single star even in the most powerful telescopes, but their double character is revealed by the spectroscope, and hence they are known as "spectroscopic binaries." If the plane in which the stars revolve lies more or less "edge on" to the earth, each star will, of course, successively move toward and from us in the course of its revolution. This causes a shifting of the spectral lines similar to that mentioned in the last paragraph. If both stars are bright enough to show spectra, the corresponding lines of these spectra will alternately coincide and separate. If only one star shows a spectrum, its lines will shift alternately to right and left. When, in such cases, the parallax of the stars is known, we can compute from wellknown laws of gravitational motion the actual dimensions of the orbits in which they revolve and the masses of the stars, notwithstanding the fact that the best telescopes do not show these bodies separately, and may not show one of them at all — a remarkable example of what has been called "the astronomy of the invisible." Many stars are observed to vary in brightness, either regularly or otherwise. When there is a regular period of variation, the spectroscope generally shows the star to be double, and the variations of brightness are apparently determined by the different aspects presented by the two components during the period of revolution. There is also good reason to believe that some variable stars are not spherical, but are elongated into an elliptical, pearshaped, or hour-glass-shaped form, and the rotation of such a star might present to us markedly varying amounts of surface. In an interesting class of variable stars known as "eclipsing variables" — of which Algol, the "demon star," is the most famous example — the principal star of a pair is periodically "eclipsed" by the passage in front of it of a less luminous (not necessarily dark), satellite, which is itself invisible in our telescopes. There are still other variables of which the fluctuation in brightness is apparently the result of periodic outbreaks of activity in the star itself, due to causes of which we have no knowledge. It has occasionally happened that a temporary star has made its appearance in the firmament, and some of these "novae," as they are called, have been of great brilliancy. The most famous of them was one which THE HEAVENS ABOVE appeared in the year 1572, and which is commonly associated with the name of Tycho Brahe, the Danish nobleman-astronomer, because he wrote a description of it, though he did not discover it. For some days it was brighter than any other star in the sky and visible in broad daylight. It then gradually faded, and at the end of sixteen months had become invisible. Another remarkable nova appeared in the constellation of Perseus in 1901. Two days before its discovery a photograph of that portion of the heavens, showing stars as faint as the eleventh magnitude, did not include it. When first observed, it was of the third magnitude, and it brightened in two days to the first, after which it rapidly faded. It is still hypothesis, supported by spectroscopic evidence, nova? are due to the passage of a normally faint or dark star through a gaseous region in space; the star being made luminous by friction, just as a meteorite becomes luminous in passing through the earth's atmosphere. Such gaseous regions are known to exist, and many of them are selfluminous, constituting some of the bright cloud-like patches in the heavens known as "nebulae," two or three of which are faintly visible to the naked eye, while probably half a million or more are within the range of the biggest telescopes, or the camera. Not all nebula? are gaseous. Many are merely distant the twelfth magnitude. Various explanations of these sudden apparitions have been suggested. The collision of two dark or faint stars in space would doubtless give rise to a great burst of luminosity, or a vast eruption of glowing matter might occur from a star that was previously quiescent (but this is an explanation that needs to be explained). According to a recent by the spectroscope. Nebulae assume various characteristic forms; some are ring-shaped, some elliptical; some (the "planetary" nebula?) disk-shaped, and almost uniformly bright throughout. Others are quite irregular in shape ; of this type is the Great Nebula in Orion, the most magnificent object of its kind in the sky. This nebula, which can be vaguely seen with the naked eye, surrounds one of the stars in Orion's sword: (a description, by the way, that is probably lost on ninety-nine out of every hundred readers of Tennyson's "Merlin and Vivien" — especially in America, where astronomy has been almost completely banished from schools and academies). Fine details of the nebulae which the eye, aided by the best of telescopes, cannot detect are revealed by long-exposure photographs. It thus appears that many, and perhaps most, of them are made up of spirally twisted wisps of light, studded with points of condensation. The camera has also disclosed the presence of faint nebulous matter spreading over great areas of the sky; in some cases enveloping a whole constellation. Just as there are dark stars, so there appear to be many dark nebulae. It is probable that such objects, silhouetted against a luminous background of dense star fields, account for some of the striking black patches in the sky, once supposed to be merely starless regions of space. great luminous band encircling the sky, presents a nebulous appearance to the naked eye, but even a small telescope shows it to be made up of innumerable stars, from the eighth magnitude down, including many dense clusters. It contains, however, very few gaseous nebulae. The number of stars in a given area of sky decreases more or less regularly as we move away from the galaxy. Thus it seems likely that the stellar universe, or, at least, the system of stars to which our sun belongs, has a more or less disk-like shape (comparable to that of a thin watch), with the sun and the solar system somewhere near the middle of it. We should see the densest accumulation of stars in looking toward the edge of the disk, and this would correspond with the galaxy. politan spirit, taken a general survey of the universe before paying particular attention to the little nook of it in which we live. It is time to say a few words about the solar system. At the center of this system is the sun; an intensely hot rotating globe, about 866,000 miles in diameter, probably of very dense gaseous matter, completely enclosed and hidden from our view by a shell of clouds, which we call the "photosphere." While our earth has a cool atmosphere, composed of nitrogen, oxygen and other substances that are gaseous at ordinary temperatures, and in which water-vapor is condensed, by cooling, into the droplets and ice-crystals of which terrestrial clouds consist, the sun, on account of its vastly higher temperature, maintains an atmosphere in which even the most refractory elements are vaporized, and its clouds, also liquefied and solidified by cooling, do not consist of water, but of various metals, with carbon and other elements. The solar atmosphere extends far above the photosphere. Immediately overlying the latter is a gaseous layer, consisting partly and perhaps chiefly of hydrogen, called the "chromosphere." In structure it may be compared to a sheet of flame, for, though we can see the photosphere through it, the chromosphere itself shines with a brilliant scarlet light, which is visible along the border or "limb" of the sun at the time of a solar eclipse. At such times long outward projections from the chromosphere are often seen, and these are called "prominences." With the aid of the spectroscope it is possible to see both the chromosphere and the prominences without an them. Some prominences are quiescent, hanging for days over the same spot, while others may be seen to shoot upward, often at a speed of from 100 to 200 miles a second, and to altitudes which, in extreme cases, amount to from 200,000 to more than 300,000 miles. Lastly, the sun has an extremely tenuous outer atmosphere, of vast extent, which is seen as a broad wispy glow during an eclipse, and is known as the "corona." The surface of the photosphere usually exhibits a few or many dark patches, of various shapes, known as "sunspots." These vary in size from tiny points, just visible in the telescope, to great blotches that can be seen, through smoked glass, with holes in the photosphere, and were formerly believed to be, at least, deep depressions in its surface; but they are now regarded as the tops of vortices, or cyclones, in the solar atmosphere. This atmosphere is undoubtedly the seat of an active circulation, analogous to the windsystem of the earth, and one consequence of the circulation is that the cloud layer, or photosphere, rotates much more rapidly near the solar equator than elsewhere ; viz., once in about twenty-five days, as compared with thirty days and upwards in high solar latitudes. The temperature at the surface of the sun far exceeds the highest that can be attained with the electric furnace, the most powerful heating the naked eye, and are actually 100,000 miles or more in diameter. The spots are transient phenomena, lasting from a few days to a few months, and changing more or less rapidly in shape. As the sun rotates, carrying the spots with it, the latter appear at one limb of the solar disk and travel across to the opposite limb. The spots look like device known to man. Estimates range up to 16,000 or 18,000 deg. Fahr. The sun's output of heat has been the object of elaborate observations with instruments, such as the bolometer and the pyrheliometer, designed for measuring the minute fraction o"f this heat that we receive on earth, and it is found to be subject to slight fluctuations; yet in Corrected to date from Todd's "New Astronomy." Copyright 1897 and 1906. Us«d by permission of American Book Company, publishers. the long run it remains substantially uniform, and probably has so remained since prehistoric times. How is this supply of heat maintained? The impact of meteors falling with enormous speed into the sun would account for part of it, but the much slower fall of the outer portions of the sun itself — in other words, a gradual shrinking of the whole body — seems to be the chief explanation. It has been computed that a contraction of only six miles per century would keep the sun at its present temperature. Several cepturies must elapse, however, before this slow shrinking, if it exists, can be verified with the telescope. The student who has familiarized himself with the constellations and their principal stars with the aid of star maps will notice in the nocturnal sky a few star-like objects, some of them very brilliant, which are not shown on the maps, and which move from one constellation to another. Their paths all lie within a comparatively narrow zone of the heavens, called the "zodiac." These are the planets. Compared with the stars and the sun they are actually of very small size, though some of them outshine any of the stars because of their proximity to us. The nearest of all the planets does not shine in our skies; it lies at our feet. We call it the earth. There are eight known planets; not counting their attendant moons, or satellites, nor the small • bodies known as asteroids, or planetoids. All the planets, with their moons, and also the asteroids, revolve around the sun in orbits that, in most cases, are nearly circular. They all shine with light reflected from the sun. gram, the total length of which indicates the diameter of the sun, on the same scale. The satellites, not all of which are shown, are not drawn to scale (those of Mars would be invisible if their relative size were not here much exaggerated). Mercury is the nearest planet to the sun. Though there has been much speculation about an "intramercurial planet" — it has even been given the name Vulcan — no such body is now believed to exist. On the other hand, it is extremely probable that one or two unknown planets lie beyond the orbit of Neptune. rotation of the earth causes the, to earth-dwellers, apparent daily revolution of the sun, moon and stars, just as the motion of a train in which you are riding causes the apparent motion, in the opposite direction, of objects outside the windows of your carriage. The moons or satellites have even more complex motions than the planets. They are carried by the latter around the sun ; they rotate on their axes; and they revolve around the planets to which they severally belong. Mercury and Venus have no moons ; the earth has only one ; Mars has two, both very small and very close to the planet. At this writing (1916) Jupiter is known to have nine, Saturn ten, Uranus four, and Neptune one ; but it is not likely that all the satellites of these four planets have been discovered. much the nearest of all celestial bodies to the earth. Her diameter is a little more than one-fourth as great as the earth's, and she revolves around our planet in about twenty-seven and one-third days. The lunar "month," determined by the relative positions of the moon and sun in our skies, is twenty-nine .and one-half days. Since the moon always keeps the same face toward the earth, she turns once on her axis while she is revolving once around the earth. planet." She is supposed to have had an atmosphere ages ago, but to have lost it, and to be devoid of moisture and incapable of supporting life. All that is certain, however, is that if a lunar atmosphere exists it is excessively rare, and that most, if not all, forms of life known to us would perish if transplanted to our satellite. Some recent observers, notably Professor Pickering, believe they have detected patches of vegetation and ice, frost or mist on the lunar surface. The moon is the most interesting of all objects in the telescope, because of the innumerable mountains — chiefly extinct • volcanic craters — which cover her surface. Many of the craters are far larger than any similar formations known on earth. Several hundred of the craters have been named in honor of early astrpnomers and philosophers. The so-called "seas" on the moon are desert plains — perhaps the dry beds of former oceans. The gravitational pull of the moon, combined with that of the sun, produces the tides in our oceans. As the earth rotates, a wave of water travels around the globe, following the direction of the moon's apparent motion, while another wave, on the opposite side of the globe, is due to the fact that the earth itself is pulled, by the moon's attraction, away from the overlying ocean. Thus at any one place in the ocean there are two tides a day. In her revolutions around the earth the moon frequently passes between us and the sun, in such a position as to obscure the whole or a part of the sun's disk as seen from portions of our planet, producing a solar eclipse. As the direction of the moon at any time with respect to the sun is not the same from all parts of our globe, an eclipse that is "total" in one region of the earth will be "partial" or nil in other regions. At any one place "totality" is very brief, lasting only three or four minutes in an average eclipse. There is a very narrow zone along which totality occurs progressively, as the moon advances in her orbit and the earth rotates (these two motions are in the same direction, otherwise the duration of the eclipse would be even less) ; on either side is a much broader zone, in which a partial eclipse is seen ; while over the rest of the earth there is no eclipse. A lunar eclipse occurs when the moon, in the course of her revolution, passes through the shadow cast by the earth, and is thus temporarily is completely immersed in the shadow the eclipse is total; if only partly immersed, it is partial. A lunar eclipse, unlike a solar eclipse, is always visible to the entire hemisphere of the earth turned moonward at the time. Mercury and Venus are called "inferior" planets, because their orbits lie within that of the earth. As viewed from the earth they seem to oscillate from one side of the sun to the other ; now appearing in the western sky after sunset, and now in the eastern sky before sunrise. Mercury's apparent position in the sky is never very far from that of the sun, and hence this planet is never above the horizon long enough after sunset or before sunrise to be conspicuous. Venus moves considerably farther from the sun, and at such times becomes a magnificent object, much brighter than any other planet or fixed star. It is probable, though not certain, that Mercury and Venus always keep the same faces turned toward the sun, just as the moon does toward the earth. If so, scorching heat must prevail perpetually in one hemisphere of each planet, while intense cold reigns in the other. Mercury appears to have little or no atmosphere; but Venus gives unmistakable evidence of possessing one, and also clouds. As to permanent surface markings on agreement. The "superior" planets, i. e., the planets whose orbits are outside that of the earth, sometimes lie in the same direction from the earth as the sun, when they are said to be in "conjunction" with that luminary, and are invisible ; sometimes in the opposite direction, when they are said to be in "opposition," and shine through the night, rising about sunset and setting about sunrise. Positions midway between conjunction and opposition are known as "quadrature." Mars, when at opposition, and therefore nearest the earth, is an object of great interest on account of the many details of its surface that can then be seen through powerful telescopes, under favorable atmospheric conditions. These markings show that the planet rotates on its axis once in about twenty -four and one-half hours ; hence its "day" is a little longer than the earth's. Near the planet's poles are two white patches, the "polar caps," which behave as if made of snow or ice, varying in size with the Martian seasons. The rest of the surface is mottled with grayish green and yellowish areas, and shows a number of dark lines and spots that have been variously reported and interpreted by different observers. Among these are the so-called "canals," described as radiating and intersecting lines of such geometrical regularity as to suggest an artificial origin. Many double or twin canals have also been reported. One hypothesis in regard to these lines is that they are irrigation channels, fringed with vegetation. This implies, of course, the present or former existence of intelligent beings on Mars. Some astronomers, however, consider the canals a mere optical illusion, due to the tendency of the eye to join up by lines any aggregation of small or faint markings. Beyond the orbit of Mars lie the asteroids, or minor planets, of which several hundred are known, while many new ones are discovered every year. The largest of these bodies is barely 500 miles in diameter, and most of them are very much Next in order comes the giant planet Jupiter, one-tenth as great in diameter as the sun, around which it revolves in a period of nearly twelve years. Jupiter turns on its axis once in about ten hours ; faster than any other planet. As in the case of the sun, we see little if any of its real surface, but only a dense layer of clouds in which it is enveloped. The planet itself is believed to be in a fluid or semi-fluid condition, and intensely hot, though hardly hot enough to be luminous. Jupiter is the second brightest of the planets, and much brighter than any fixed star. Saturn, which lies next beyond Jupiter, is unique among the planets in the possession of a system of flat and rery thin rings, like circular disks of paper perforated in the middle. According to the position of the planet with respect to the earth and the sun the rings present very different appearances, and at times disappear altogether, at least in ordinary telescopes ; viz., when they are "edge on" to us, or "edge on" to the sun, or, again, when they turn toward us the side on which the sun is not shining. At other times they are broadly elliptical and conspicuous in a small telescope. These strange appendages were long a puzzle to the astronomers, but are now known to be made up of innumerable little bodies, comparable in size to meteors, revolving around the planet. Saturn exhibits cloud-belts, like those of Jupiter, though less distinct, and its structure is probably similar to Jupiter's. Uranus is barely visible to the naked eye. It was the first planet to be found with the telescope, having been discovered in 1781 by Sir William Herschel, who at first supposed it to be a comet. All the planets with which men were then acquainted had been known from antiquity, and the discovery of a new one created a great stir. Much more remarkable, however, from a scientific point of view was the discovery of Neptune, in 1846. The position of this planet was computed before the planet itself was seen, solely on the basis of irregularities in the movements of Uranus, which were evidently due to the disturbing influence of another and undiscovered member of the solar system. The and Adams in England, and the planet was found by the astronomers at the Berlin Observatory at the place where Leverrier told them to look for it. Neptune is invisible to the naked eye. Its distance from the sun is 2,791,000,000 miles, and its "year," i. e., its period of revolution around the sun, is 165 of our years. It has therefore not made half a circuit since its discovery, in the days of our grandfathers. terror, are commonplace to the modern astronomer, who, with his telescope, finds half a dozen new ones every year. About one-fifth of these become, at some time in their history, bright enough to be seen with the naked eye. While many comets, especially the fainter ones, have no visible "tails," a few have displayed more than one of these appendages. The tail is always directed away from the sun, and often attains a stupendous size ; some have been more than 100,000,000 miles in length. Most astonishing is the fact that, in spite of their size, comets are always excessively light; mere feathers compared with any of the planets. This is proved by the fact that they do not produce the slightest disturbance in the movements of planets or satellites near which they pass, though their own movements are greatly modified by these approaches. Comets are self-luminous, but their brightness is doubtless increased by reflected sunlight. Many of these bodies are permanent members of our system, performing their revolutions around the sun at intervals of a few or many years. Others, so far as we know, make this circuit only once, and then dash away for all time into outer space. Meteors, or shooting stars, appear to be intimately related to comets, and may be produced, at least in part, by the distintegration of the latter. These bodies only become visible to us when they pass through our atmosphere and are made Ominous by friction. Millions of them enter the atmosphere every day. Most of these are probably vaporized and dissipated, some pass on into space, and some reach the earth as meteorites. Vast swarms of mete- in regular orbits around the sun. The "zodiacal light," a faint glow extending along the zodiac in both directions from the sun, and best seen in our latitudes in the evenings of February and March, is probably due to sunlight reflected from a great ring of meteors. CBATERS ON THE MOON T nr^P scalp nhotoeraph of a small section of the lunar surface. The prominent crate"near the middle of the picture is Bullialdus. Near the left margin IB tb« formation known as tue "Straight Wall." THE NORTHERN HEAVENS The maps shown on the following pages represent the heavens as seen, on the different dates given, from stations in and about the latitude of New York (40° N) It is not an' easy matter to recognize the stars by looking at the map. A certain amount of study is necessaiy ; for, of course, the different stars of a constellation are not linked together by lines as they are in the map and furthermore their magnitude is very much exaggerated. The best plan for the novice is to start with a well known constellation, such as that of the Great Bear. The "Dipper" which is a part of the Great Bear is so conspicuous a group in the northern skies that anyone can point it out. Knowing the Dipper, the Pole Star may readily be discovered by tracing a line from ft through a of the Dipper ana about five times as far. Around the Pole Star (Polaris) which is of the second magnitude, the entire northern heavens appear to revolve once a day. Having found the Pole Star the constellation of Cassiopeia may be found by extending a line from < of 'the Dipper through the Pole Star and as far again to the other side, where a cluster of stars in the form of a large ragged W will be found. If we run a line diagonally from a of the Dipper through y and about eight or nine tunes as far again, we shall come to the first magnitude star Spica, in the constellation of the Virgin, while a line extended from a through ft and about eight times as far again will bring us in the midst of the constellation of the Lion. At the eastern end of this constellation, is the second magnitude star Denebola, and the distance from this star to Spica is about the same as that from Spica to Arcturus, the first magnitude star in the constellation of Bootes. Thus we may proceed building up our knowledge of various groups and using these groups as reference points to find new constellations. Contrary to custom in geographical maps, our star maps are drawn with the east on the lefthand side and the west on the righthand HEAVENS. side, while north is at the top of the page and south at the bottom. This is due to the fact that the heavens are viewed looking upward, while the geographical map is viewed looking downward. In locating stars and constellations, it is best to hold the map overhead when the actual pomes of the compass and those marked on the map will bear the true relation to each other. NIGHT SKY: JANUARY AND FEBRUARY If one views the heavens on the hours specified under our map of January, he will find almost directly overhead a bright star with a triangle of lesser stars beside it. The bright star is Capella or the Little She Goat which is held on the arm of Auriga, the Charioteer, whose left hand is represented by the triangle of stars, >j, e, £ The constellation bears no resemblance whatever to a charioteer or a goat. In fact, very few constellations bear any resemblance to the objects the ancients supposed them to represent. Halfway between Capella and the southern horizon are the three bright stars forming the belt of Orion. They are indicated in the map £, «, 4. and they are centered in the square formed by the stars, Betelgeux, Bellatnx, Rigel and th« star noted by the letter «. The little triangle of stars at A mark the head of Orion, whae the line of fault stars at ir represents a lion skin that Orion is holding forth towards the constellation of Taurus, the Bull. The principal star of this constellation is Aldebaran, a bright red star, marking the left eye of the bull, while his two horns are indicated by the stars ft and £ The star e is at the nght eye of the bull, and y at his nose. - They form with Aldebaran a triangle that is easily recognizable. A little to the west of this group is the interesting star cluster of the Pleiades. In this cluster, there are six stare easily visible to the naked eye, and many can see seven stars, while observers with exceptionally good eyesight have been able to see as many as fourteen stars. A small spyglass will reveal large numbers. The stars forming the belt of Qnon point in-the general direction of the first magnitude star Sirius in the constellation of Canis Major, the Great Dog. Sirius is by far the brightest object in the heavens if we exclude the sun, moon and planets. It is one of the nearest suns outside our solar system, yet it is so far off that it takes nearly nine years for its light to reach us. The diameter of Sirius is about twenty times that of the sun and its volume is about seven thousand times greater. In the constellation of Canis Major there are two other first magnitude stars, but Sinus so far outshines them that they look no brighter than second magnitude stars. If we follow the line from Aldebaran eastward beyond f we come tD the constellation of Gemini, the Twins, marked by the two bright stars, Castor and Pollux; while south of this constellation is the first magnitude star Procyon •ia the constellation of Canis Minor, the Little Dog. It will be noticed that most of the constellations so far referred to lie adjacent to the Milky Way. If we follow the Galaxy northward, we find just beyond the constellation of Auriga, the constellation of Perseus, whose most interesting star is marked P and l> known as Algol, the Demon Star or the Winking Demon. Every two days. twenty hours and forty-nine minutes, this star begins to fade until, in the course of three or four hours, it loses four-fifths,of its light. Then it begins to become brighter until eventually, after three or four hours more, it reaches its normal brilliancy. The star marks the head of Medusa, which according to the Greek legend Perseus was carrying when he came across Andromeda chained to the rock. Further north along the Milky Way we come to Cassiopeia. In the northeast is the great dipper forming part of Ursa Major, the Great Bear; far in the east is the constellation of Leo, the Lion, in which are the prominent stars Regulua. Denebola. The curved lins of stars ending with Regulus is known as the Sickle. NIGHT SKY: MARCH AND APRIL. Our map for March and April shows most of the constellations along the Milky Way low in the western sky. The great dipper is well up near the zenith with its pointer scars p and a indicating the position of the Pole Star, Polaris. Oddly enough the ancients represented the great bear as having; a long tail, indicated by the stars e, f, r?. These are the only stars that follow the outline of the beast. The star o is at the bear's mouth, while the stars , i, and M, , and v, f represent three of his feet. The star £ is interesting because it hai a small companion, called by the Arabs "Alcor." A little to the south of the zenith ia the constellation of Leo, referred to in the small groups known as Corvus, the Crow, spicuous; neither is Hydra, the Sea Serpent, which stretches its long length across the southern sky. Its brightest star is Alphard which is of the second magnitude. Above the head of the serpent is the inconspicuous constellation of Cancer, the Crab. An interesting feature of this constellation is a faint star cluster, just visible to the naked eye and marked on the map Praesepe, the "Beehive." In the telescope this is seen to be made up of a myriad of small bright as- the Wandering Star for the reason that it is slowly drifting with respect to the other stars in the Heavens. Since the time of Christ it has moved in a southwesterly direction, fully one degree, or through a distance equal to twice the diameter of the moon. Its yearly displacement is two seconds of arc. South of Bootes is the constellation of Virgo, whose brightest star is Spica. Between Virgo and Ursa Major are two faint constellations known as Coma Berenicis. Berenice's Hair;, and Canes Venatici, th«J Hun ting Dogs. Close to the southern horizon is the constellation of Centaurus. the Centaur, Not very much of this constellation can be seen from our latitude. Its brightest stars lie below the horizon. They include a Centauri, the nearest body outside the solar system. This star is only 255,000 times as far from us as we are from the sun. It takes its light 4J years to come to us. In the southeast, low down near the horizon may be seen the constellation of Scorpio, the Scorpion. This constellation is made up of a very easily recognizable group of stars. It contains the brilliant first magnitude star, Antares, at each side of which are the lesser stars <r and T. A line of stars traces the form of the Scorpion as shown to better advantage in the next map. The Scorpion embraces in its claws the constellation Libra, or the Scales. In the north above the Polar Star, we may see the body of the Little Bear, TTrsa Minor. Most of the stars of this constellation are faint with the exception of Polaris and two stars fl and y which have been called the guards. Between Ursa Minor and the Zenith, the constellation Draco, or the Dragon, twiner its long form. The stars y, $ and £ teark the head of the dragon. To the eastwara of the constellation Bootes is a partial ring of stars known as Corona, or the Crown. This is one of the few groups actually outlining the object it is supposed to represent. The Zenith constellation for July and Au?ust is Lyra, the Lyre, with its bright bluewhite star, Vega, nearly directly overhead. Just west of the Zenith is the constellation Haroule? whose star^ form a ragged-looking H. Below this constellation is Ophiuchus who hvj in his grasp the constellation Serpens or tie Serpent. Low down in the south the constellation of Scorpio has dragged its full length above the horizon and it is easy to ^trace its body and tail ending with the stars A and v. The opposite side of the Milky Way now stretches its length across the sky, containing in its extent many brilliant constellations. Just east of Scorpio is the constellation of Sagittarius., the Archer. Well up in the southeast is the star Altair cf the constellation Aquila, the Eagle, and just above Altair is the tinv constellation, Sagitta or the Arrow. To the east may be seen Delphinus, the Dolphin.while to the east oi Lyra is the constellation of Cygnus, the Swan. NIGHT SKY: SEPTEMBER AND OCTOBER. Our map for these two months shows no constellation , immediately overhead. Halfway between the Zenith and the Pole Star is the constellation of Cephas, a badly formed W made up of stars that are not very bright, with the exception of a which is of second magnitude. The Milky' Way now stretches overhead and makes a beautiful sight on a moonless ni(?ht. About thirtv degrees south of the Zenith is the constellation Pegasus. Its three stars, y, a, and ft form with the star o of the constellation Andromeda, a large square known as the "Square of Pegasus." Below the constellation Pegasus is that of Aquanus, the Water Bearer, while to the southwest is the zodiacal constellation 9f Capricornus, the Sea Goat. This constellation is marked by a very pretty naked eye double at a. The most conspicuous star in the south is Fomalhaut, of the Southern Fish. This brilliant star can hardly be appreciated in northern latitudes because it is not very favorably placed for observation. Below Fomalhaut is a bright little group known as Grus, the Crane. Running westward from the zenith stretches the constellation of Andromeda, the chained lady who was rescued by Perseus. In this constellation may be seen a faint nebula which in a telescope as shown to cover an enormous extent, a great whirl of nebulous material Probably it represents a star in the making. The great square of Pegasus lies just to the Jouth of the zenith. The southern sky is filled by the constellation of Cetus, the Whale. The most interesting star in this group is that of Mira, which on the average of once in eleven months, blazes forth with a brilliance, sometimes exceeding the second magnitude Generally, however, it does not exceed the third magnitude, while its normal brightness U such that it is barely visible to the naked eye. Between Cetus and the zenith are three small constellations, t. e., Pisces, the Fishes. Aries, the Ram. and Triangulus, the Triangle. In the southeast sky is the wandering n ver, Endanus, while the eastern sky is filled with brilliant winter constellations described in the paragraph on the January. and February map are those who sing the praises of London, Paris, Vienna, Berlin, Rome, Petrograd, and all have claims well substantiated. But in plan, architectural beauty, embellishment, cleanliness, convenience, absence ol poverty, spaciousness, interest, educational facilities — in all resentation in the taxing body, governed without their consent, and made to stand by and look on at the spending of their money without a word to say (officially) as to how it shall be spent. And — strange though it seems in American eyes — this plan of the National City being taxed and governed by the National Government has resulted in the that makes a city noted above other cities, Washington, the Nation's City as well as the Nation's Capital, stands unique and unapproachable. Most American of all cities, since it is owned by the Nation's Government, it is not less patriotic that it is the one spot in all free America where people are taxed without rep- Considered as a municipality, entirely apart from governmental activities, Washington can hold up its head among the best. In streets, parks, and shade trees, in recreation centers, police, fire and school systems, in privileges and pleasures, Washington is behind none of its size and ahead of many larger cities. It has a minimum amount of crime, a comparatively small indigent and poverty-struck population, no foreign quarters, a climate which suf- President and confirmed by the Senate, act as a combined Mayor and City Council for the District of Columbia's seventy square miles of territory, having charge of all departments of the local government. Washington is taxed as other municipalities are taxed, but the money is spent by Congress, which adds a sum sufficient to make that raised by taxation exactly half of the total appropriated for any one year. In return for this "half-and-half principle" as it is known, all Government property — and the Government, of course, owns the most valuable PANORAMA OF WASHINGTON fers more from ill-repute than Washingtonians do from its warm summers, a just and liberal Government, no graft, party politics or factional fights, and, because it lives in and among the greatest law-making body in the world, a better comprehension of national problems than is possible elsewhere. CITY GOVERNMENT Three commissioners, one of whom must be a major in the Army Engineering Corps, appointed by the land and buildings in the city — is free of taxation. The result of a wise and liberal policy of city improvement has been the making of a municipality with more shade trees in proportion to its population (95,000 trees) than any other in the world, a city with a greater percentage of paved streets per population than any other in the world, a city with wider streets, straighter streets, cleaner streets than any other in the world, and the establishment of a parking system which THE CITY PLAN The original plan of the city contemplated its growth in an easterly direction across the plateau which forms the top of Capitol Hill, on the summit of which stands the The city perversely grew the other way, so that the wealthy residence and all the business section, streets are numbered, those running east and west are lettered. The avenues, named for states in the Union, all run at various angles. The city is divided into four sections— Northwest, Northeast, Southwest, and Southeast, the division lines being North, East and South Capitol Streets, and an imaginary line running through the park and practically all the Government buildings and activities, are west of and therefore to the rear of, the Capitol. Luckily, the rear elevation of the Capitol is as beautiful as its actual front. nues radiating from the Capitol and White House, are other slanting arteries of travel, confusing to the visitor, but making every part of the city quickly accessible from every other part to those who know how to take advantage of those hypothenuses of triangles. At junction points of lettered and numbered streets and avenues are parks, circles, or statues, productive of those vistas and beauty spots which have PABKING SYSTEM Five great parks of many acres, twenty-six of more than one acre and two hundred and seventy-five smaller ones (not including the great military reservation at Fort Myer, Virginia, just across the river, and connected by a bridge with the Speedway), constitute a parking sys- and Lincoln Memorial (not yet completed). The Mall gives way to the Speedway, a river park made from reclaimed land, where there is swimming and boating and baseball, golf, tennis, polo and cricket grounds are to be found, band concerts occur and thousands of pedestrians, motorists, horseback riders and drivers have a place close to the heart of the city in which to enjoy their favorite recreations. WHERE AN INAUGURATION IS HELD, AND THE PROCESSION tern which has no equal in the world. Splitting the heart of the city east and west from Capitol Hill to the Potomac River is the Mall, a wide park on which are located (mentioned in order from the Capitol, going west) the Bontanical Gardens, the Fish Commission, Medical Museum, old National Museum, new Building, Washington Monument, North of the Northwest Section is the National Zoo, where nearly 1,500 animals of all sorts have comfortable and beautiful homes, in many cases in natural surroundings. Connected to the Zoo is the National Park, a reservation devoted entirely to natural recreation. Far-seeing statesmen recognize the need of all cities for ample parking space, and beautiful Rock Creek Valley has been preserved for all time to the Nation, nothing being done to it but the providing of miles en miles of velvet roads and necessary bridges and fords. The combined area of Zoo and National Park is 1,776 acres. North of the Capitol and east from the National Park lies Soldiers' Home Park, a beautiful hilly country with many fine roads, where the Nation maintains a magnificent home for its disabled soldiers. Plans now under way contemplate the connection of Zoo and National Parks with the Speedway and Mall, by driveways along the unimproved TON, D, 0, part of Rock Creek Valley, a plan which, when complete, will enable a motorist to drive for five or six hours without going over the same' road twice, or even running on a city street, and yet be at no time more than a few miles from the They are so numerous that a complete catalogue would be wearisome. The visitor usually makes first for the Capitol, on Capitol Hill, where he also finds the indescribably wonderful Library of Congress, the two huge office buildings devoted to the use of Senators and Representatives, the Union Station — second to none in the world in beauty, and with a concourse capable of housing the entire standing army of the United States — all in an extension of the Mall. The White House, or Executive Mansion, stands between the Treasury and State, War and Navy Department Buildings, fronting on Pennsylvania Avenue, and giving to the rear on the "Ellipse," a part of the Mall. In the heart of the city are the Post Office, Pension Office, Land Office and Patent Office buildings (this latter tee office also of the Secretary of the Interior) and scattered everywhere are related branches of the several departments. On the outskirts of the city are the United States Naval Observatory, whore, among other things, is the great 26-inch refractor with which the moons of Mars were first seen, the Bureau of Standards, and further out, the first settling reservoirs of Washington's wonderful water supply system, which includes a filtration plant which provides crystal water regardless of the mud which may be in the Potomac. All Government buildings may be visited by visitors prior to two o'clock, and no charge is made anywhere. Any official in the Government, from the President down, may be seen by any one with legitimate business, and every facility is put at the disposal of him who seeks information by every department of the Government, with the exception of those necessarily restricted by their very nature — such as Army and Navy and Secret Service. There are many buildings, bureaus and activities which are wholly or partly separated from the Government. The National Geographic Society, the City Library, the Volta Bureau, the Bureau of American Republics, the stupendous Scottish Rite House of the Temple, the hos- non, Washington's Home, Annapolis, where they turn out Naval officers, Great Falls, wild and rugged in beauty, source of the city water supply and historic in that George Washington dug a canal around them, the remains of which are still to be seen, beautiful Harper's Ferry, historic in Civil war days and magnificent in scenic beauty, Baltimore, forty miles distant by road or rail, Alexandria, Arlington (home of the Lees, and now the National Burying Ground) are all within an hour and pitals, schools, colleges, universities, private laboratories, Carnegie Institute, etc., all add to the educational possibilities of the city. A dozen or more interesting localities surround the Nation's City. The Navy Yard, where the big guns are made, the Arsenal Grounds, with the War College, St. Elizabeth, the home of the Nation's insane, Columbia Institution for the Deaf and Dumb, Continental Hall (D. A. R.), Corcoran Art Gallery, Mt. Ver- a half of the Capitol, some within a few minutes' travel, while Norfolk and the Newport News shipyards are but a night's boat ride away. Visitors not infrequently ask the length of time necessary properly to see the Nation's City. The resident, who knows, usually answers, "Not less than a year," and there is truth in the statement. SCOTTISH RITE TEMPLE AT NIGHT lections say that a year is hardly enough really to see, let alone study, the wonders of either the Museum or the Library of Congress. So to those who may find in this brief sketch or the pictures which accompany it, any impetus to visit that city which is most truly American, and which belongs in part to every American, it is said, "Stay as long as you can and do not think that a visit to every Government building in Washington, which could not possibly be accomplished in a week, means that you have really seen the treasures which are yours. For Washington, belonging to the Nation, is its treasure house, and collected, kept, and made accessible here are such treasures of age, of curiosity, of interest, of educational value, of patriotic association, of real Americanism, as will require more time to see and appreciate than any have time to give — which fact is in itself one of the many things which makes the Nation's THE STATUE TO DAGUERRE City an inspiration and an example of all that is best in the ideals which make the L'nited States "one nation indissoluble." THE HEART OF THE NATION THE United States Capitol Building is the political and sentimental center of the United States, however far removed it may be from the geographic center. Aquia Creek, Va., was laid with Masonic ceremonies September 18, 1793, by President Washington. The original designs were prepared by Dr. William Thornton, and the work was done under the direction of Stephen H. Hallet, James Hoban, THE CAPITOL AT WASHINGTON teau 88 feet above the level of the Potomac, situated in latitude 38" 53' 20.4" north and longitude 77° 00' 35.7" west from Greenwich. The southeast cornerstone of the original building, constructed of sandstone taken from quarries on George Hadfield, and B. H. Latrobe, architects. The north wing, finished in 1800, and the south in 1811, were then connected by a wooden passageway ! On August 24, 1814, the interior of both wings was destroyed by fire, set by the British. But the damage was immediately repaired and in 1818 the central part of the building was begun, under the architectural superintendence of Charles Bulfinch and was completed in 1827. Up to 1827 the total cost of building and grounds was $2,433,844.13. The cornerstone of the extensions was laid on July 4, 1851, by President Fillmore, with Daniel Webster officiating as orator. Thomas U. Walter directed the work till 1865, when he resigned, and it was completed under the supervision of Edward Clark. White marble from al cost of replacement. The building stretches from north to south 751 feet 4 inches, and from east to west 350 feet is its greatest dimension. The area covered by the building is 153,112 square feet, more than 3.7 acres. The original dome was of wood, covered with copper, but this was replaced by the present structure of cast iron in 1865. With the bronze statue of Freedom on top, 19 feet 6 inches high, the total weight of the dome is 3,983 tons. The dome THEREFORE the quarries at Lee, Mass., was used in the walls and the columns came from quarries at Cockeysville, Md. The House extension was first occupied for legislative purposes December 16, 1857, and the Senate January 4, 1859. The Capitol Building and Grounds are officially valued as follows: Building, $15,000,000; grounds, $10,400,000; total $25,400,000. But the is 287 feet 5 inches above the base line of the east front and 217 feet 11 inches above the top of the balustrade of the building. Its greatest diameter at the base is 135 feet 5 inches. The dome surmounts and Covers what is known as the Rotunda, a circular room 97 feet 6 inches in diameter, and is 180 feet 3 inches high from the floor to the top of the canopy. THE LEGISLATIVE HALLS The three great Government activities housed by the Capitol are the Senate, House of Representatives and the Supreme Court. ber is located in the left wing of the Capitol, or, as is better known, the North Wing. It has seats, of course, for the ninety-six senators who compose the Senate — two from each State regardless of size or population— and is surrounded with a gallery, in which more than a thousand spectators can find seating place. The room, 113 feet 3 inches long by 80 feet 3 inches wide and 36 feet high, is chaste, almost severe in architectural design (see picture), although the iron and stained glass ceiling gives a touch of color with the coat of arms of each State. The Senate is entirely too dignified a body ever to permit itself to be photographed, but is free in its welcome of visitors. The galleries are always open except when the Senate is in Executive session, when even the reporters', diplomatic and senators' private galleries are emptied and locked. Arranged in a succession of semicircles, the senators' individual desks are all within sight and voicereach of the chair of the Vice-President, who presides over the Senate. Democrats sit on the Vice-President's right, and Republicans on his left, a general statement which hardly holds good when the Senate is in session, because senators move Ordinarily no one is permitted upon the floor of the Senate save present and ex-legislators, the pages who serve them with books, carry messages and run errands, such clerks and officials as are a part of the official life of the Senate and representatives of certain newspapers and press associations. Only when the "Thanks of Congress" have been given to some fortunate individual is this rule abrogated, the "Thanks of Congress" carrying with tors at their pleasure. Directly opposite, in the South Wing of the Capitol, is the House of Representatives, where the 435 members of the House have their deliberations. It is similar in arrangement to the Senate, but is much larger, being 139 feet long, 93 feet wide and 36 feet high. Its galleries will seat more than 2,000 people. The House has not space to provide each member with a desk ; indeed, if the country keeps on growing and the House keeps on in its present way of thinking, it will not be able to provide all its members with seats in a short while. As every one knows, the House itself fixes the population of a district which shall entitle that district to one representative, but to increase the population quota with regard to the increase in the total population only, would be, for instance, to increase New York's representation and decrease that of some western States not growing so fast, or some eastern States, like Delaware and Rhode Island, which naturally grow more as larger States. The House is generally admitted, even by itself, to be unwieldy in size, now that it possesses 435 members, exclusive of the delegates from non-contiguous possessions. What it will be when a new census is taken and a new apportionment made, no one can say. Meanwhile, semi-circular rows of seats serve the members apparently as well as do their desks the senators. For no member gets a chance to make a speech of such length as will require voluminous notes, reports and books, speaking time being the most precious possession in the House. In the Senate, where any senator who can get the floor can speak until dumb from throat paralysis, a desk capable of holding a good-sized slice of the Con- gressional Library — with which the Capitol is connected by a subway with electric book carrying trains — is a vital necessity. No place in the world has a greater interest to the public than the National Legislature of the United States. Two hundred and fifteen newspapers and press associations have 304 representatives to the press galleries of both houses, and a majority of these are on duty every hour of every session of Congress. Of course, during executive sessions, all newspaper men are excluded, but as many of the press representatives make it their business to have intimate friends among the members of Congress, there is little if any- sentatives, forming together the Federal legislature, commonly called Congress, are entirely dissimilar bodies. The House of Representatives lives for only two years, then dies completely, a new House being formed by the biennial election of the 435 Representatives of the people of the various States. The Senate never dies ; it has been a continuous body since its first ereation. Senators are elected for six THE CONGRESSIONAL LIBRARY thing which is really secret. Indeed, both Congress and the President trust the newspapers far more than is generally realized, and it is a credit to the profession that what should be kept under cover for diplomatic reasons, is concealed, not because of absence of knowledge on the part of the correspondents, but because of loyalty and patriotism. It would be idle to discuss whether the Senate, the House of Representatives, or the President of the United States is the most important factor in its government Clothed by the wisdom of the founders of the but a senatorial election is held every two years, one-third of the members of the Senate going out of office biennially. The result of this system is that a majority of the Senate is always composed of older and experienced members. Inasmuch as many Senators are re-elected, term after term, there is always a large proportion of men of ripe experience and long service in the upper house of Congress. Any variety of legislation with one important exception can originate in either branch of Congress. Appropriation bills can only originate in the House of Representatives, but no appropriation bill can become a law until it is concurred in by the Senate. No bill of any sort, whether originating in the Senate or the House of Representatives, becomes a law until it has been to the President for his signature. He is supposed to return these bills to Congress within ten days. If he signs the bill it becomes a law ; if he fails to sign in ten days a bill automatically becomes a law. If, however, the President returns a bill vetoed, that is, with his signature refused, difference between 218 and 290 is 72, the theoretical voting power which the President possesses in the House of Representatives. In the Senate, the bare majority of the 96 Senators is 49 and a twothirds majority necessary to pass a bill in the Senate over the President's veto is 64, the difference being 15 Senators, representing the theoretical power of the President in vote in the Senate. Methods of work in Senate and House are entirely different. There is no attempt in the Senate to limit the speaking of a Senator on any STATE, WAR AND NAVY BUILDING, WASHINGTON, D. C. it is required that the bill be passed again by both Houses of Congress 6y a tico-thifds majority before it can become a law. This is equivalent to giving the President the power to vote in the negative, in theory at least, of seventy-two Representatives and fifteen Senators. If a bill be passed in the House of Representatives by a bare majority of one of the 435 members it will receive 218 votes in the affirmative against 217 in the negative. If, however, the President vetoes the bill, it will require 290 votes to pass it, 290 being two-thirds of 435. The subject. He, therefore, can talk as long as he desires and a "filibuster," as it is called, when some Senator or group of Senators desires to defeat a bill by talking it to death, or talking until Congress expires, or until its opponents are so disgusted that they will yield to the "filibuster," is not of infrequent occurrence. No such procedure is a possibility in the House. In the House debate is limited by the rules or by mutual agreement to a certain length of time. When a bill is introduced into the House, it is immediately referred to some committee. There are fifty- nine committees in the House and seventy-five in the Senate. In addition there are a number of joint committees. tees in the House are those on Ways and Means, and Appropriations, and membership in either is a mark of confidence by the House. The House elects the Ways and Means Committee, which acts as a Committee on Committees, and it appoints all the other committees. Chairmanship of a committee is a matter of seniority of service in the House. FOST OFFICE DEPARTMENT BUILDING House as a whole except as referred to the House by the committee or by unanimous consent. Therefore, the committee is extremely important to all legislation and nine out of ten of the thousands and thousands of bills of all kinds, which are proposed in the House, are quietly strangled in committee and never see further light. Inasmuch as many such bills are proposed merely for "home consumption" and in order to make an impression on the "folks back home," this system works out without hardship either to the Representative proposing the bill, the bill itself, or the House of Representatives as a whole. The committee, the members of which may be anywhere from three to twenty in number, will debate a proposed bill, hold public hearings for the benefit of interested parties, make amendments to it, and finally offer it, perhaps in a completely changed form, back to the House for consideration. The House can then pass it or reject it at its pleasure. Having succeeded in passing the House, such a bill goes to the Senate and the Senate can then either pass it or reject it. In the more common cases a bill passed by the House which is not entirely pleasing to the Senate is revised or amended by the Senate and then sent back to the House. In case it is impossible for the two branches of the Legislature to agree upon a bill, a Conference Committee is appointed, usually of three members of each House, which Conference Committee meets and endeavors to effect a compromise and the com- Houses of Congress. No story of the House of Representatives would be complete which did not contain a few words of reference to the most powerful figure in the House, who is, of course, the Speaker. The Speaker at one time appointed the members of all committees, including that of the Committee of Rules, which determines the order in which important measures shall come before the House. In the old days he was himself chairman of this committee, but, in 1910, the House took this power away from its Speaker. It increased the Committee on Rules from five to ten and agreed that the House itself should make the appointments, This has shorn the Speaker of his previous power but he still has plenty left. He can recognize or refuse to recognize any member trying to address the Chair and can thus accelerate or retard the passage of any bill. The fact that the House elects usually as its Speaker a national figure in politics and a man of great force of character as well as of brains is one of the safeguards of the national legislature. He is, of course, invariably elected by a strict party vote, a Democratic House of Representatives becoming the more powerful as a Democratic organization by possession of a Democratic Speaker, the same obtaining for a Republican House. The wisdom of our forefathers in providing for a Senate, composed of two men from each State, representing the States, and not the people, to act as a check upon the Representatives of the people in the House of Repi-esentatives, is continually made manifest. The Senate acts often as a brake upon the too headlong action of the House and many an ill-considered piece of legislation, enacted with insufficient debate, and, perhaps, in the heat of partisan feeling in the House, has been so altered in the Senate that its originators could not recognize it when it finally came back to them. The final bulwark of the people against wrong action on the part of the National Legislature is the Supreme Court, which must pass upon the constitutionality of disputed enactments; and with first a committee, next a House, then a Senate, then, perhaps, a joint committee, again an action by both House and Senate, a possible veto, a re-enactment over that veto and finally possible review by the Supreme Court, as to the admissibility of legislation under the Constitution of the United States, that law must be ingenious indeed which is unjust or ill-advised when finally read into the Statutes of the United States. SUPREME COURT If the Senate feels its dignity to such an extent as never to yield to the blandishments of the press photographer or motion picture director, what must be said of the Supreme Court? To imagine this body permitting itself to be photographed is an impossibility. Of course, there are plenty of photographs showing the Supreme Court in session, but none of them are real. All are made by combining pictures of the various justices with an interior of the Court ; a real photograph has never been made. The Supreme Court room was formerly the Senate Chamber. Until 1859 the Senate met in the present Court room, the Court then sitting in the room beneath, which is now the Law Library. It is a simple and impressive room even when unoccupied, and when the Court is in session no American can look upon its deliberations unmoved, for it represents to him the very apotheosis of the democracy on which his nation is built, the justice and liberty which make America, America. As every American knows, the Supreme Court is the one branch of the Government which has absolutely no connection with politics, with patronage, with partisan methods of any kind. Justices, appointed for life, can only be removed for high crimes or misdemeanors, and no justice ever has been removed since the Court was founded- Presidents with Supreme Court vacancies to fill have all realized that the American people would scrutinize their appointments with the keenest eyes, and let the Senate know in no uncertain manner if they did not approve. The result has been a continuing body which represents the highest legal and personal attainments, and one which, although it often makes decisions which are unsatisfactory to many people, is never questioned as to its integrity bv its most violent critics. UNITED STATES SUPREME COURT Bench is justly regarded as exceeded in honor only by the Presidency, and many contend that as the one is a permanent appointment, the other but a temporary position, the nine Supreme Court Judgeships represent the nine highest honors America has to offer. Certain it is that no man who has sat on the Supreme The Court sits from October to June, from noon until 4 P. M., five days in the week, reserving Saturday for consultation. Strangers are permitted to visit the court at all times, although accommodations are limited. monarchs. On the other hand, the President of the United States enjoys certain privileges and powers not possessed by even the rulers of absolute monarchies. The three principal functions ofthe President may be stated' as a control of foreign relations, those powers which are concerned with legislation, and those which relate to the domestic administration, the latter largely concerned with the matter of appointments and patronage, particularly in the appointment of members of the Supreme Court. A question frequently asked of those who know, and especially by new Congressmen who come for the first' time to the great legislative halls upon Capitol Hill, is "What is the form of the President's power over "Congress? " By rwhat means does he "bend this immense legislature representing the forty-eight States 'and- the -hundred -million of people,, to his will?" The answ.er to this question is extremely complicated if taken up in detail, but -in . its broad essentials the control of the President over TELEGEAPH ROOM, EXECUTIVE OFFICES, WHITE HOUSE foreign affairs, but is checked in his control of the foreign relations of the United States by the Senate, which must approve by a two-thirds majority all treaties negotiated with a foreign country through the Department of State for the President. While the powej-.to .declare, war belongs entirely to Congress, it ' is " perfectly possible for an Executive, without an get of 'Congress, virtually to engage in hostilities. An example of this is recent within the public mind in the expedition sent across the Mexican border. A somewhat similar case occurred in 1845 Congress may be stated to lie in four great things. In the first place, there is that political unity of a party which means so much to the politician. Supposing that the President has a majority in Congress (and few Presidents have made much headway without it), the Congress" is naturally desirous of appearing before the country as supporting and aiding the President in his work. The President then has the political power of his party behind him in any request which he makes of Congress or any suggestions which he gives them. This more or less sentimental consideration, however, is probably of less avail than the three great prerogatives which the President has. These are, of course, the power of vetoing legislation passed by Congress, which does not meet his views, the power of calling an extra session of Congress and the power of making n u m e r o u s appointments, many of which serve as "payments" for political .work or for something . done for -the President by some Congressman. .or; Senator, .President responsible for the conduct of the Government and are usually with him, right or wrong. Senators and Representatives know that when a bill is vetoed, they will have to explain and explain pretty promptly to their constituents Just why they are right and the President is wrong if they are going to, to use a slang phrase, "get by with it." It has sometimes been suggested by some members .of Congress who .did- not want legislation desired by .the White Bouse, to: pass, .that by SOCIAL ACTIVITIES times in a veiled threat to once in actuality. More than one Senator or Representative has been quietly told, perhaps by the President, more likely by some friend, that this or that particular bill has no opportunity to pass unless a two-thirds majority can be mustered. This threat of the veto is usually sufficient to keep undesirable legislation from passage. Every Senator and Representative knows that the people of the United States hold the making an agreement to end the session of Congress on such and such a day and so arranging matters that the objectionable legislation did not come up, the President might be circumvented without an open break. Older members, however, know that the Congress has power only to end its deliberation. The President has the power, guaranteed under the Constitution, of calling a special session at any time when it may be necessary to do so. More than one President has informed a Congress, anxious to end without passing legislation which he deemed necessary, that if it did so, a special session would immediately be called. Here again is the necessity for the legislator to explain to his constituents just why there is an extra session! The majority will not believe the President called a special session of Congress without a reason therefor and the question most naturally arising is "What is that reason?" If it had to be explained to the people that Congress time become that recent Presidents have ruled that they positively would not see office seekers. Mr. Wilson has gone even further and refuses to discuss patronage matters with Senators, Representatives or politicians. Unquestionably, all Presidents have had to break their rules at times, but generally this refusal has served to give them much time for the public business which would otherwise be wasted. Most Presidents refer officer seekers to heads of departments and thus lift from their 3ANQUETS has been negligent or has been attempting to pass over its responsibilities and failed to support the President, there is naturally apt to be fireworks at the next Congressional election. The appointive power of the President has its drawbacks. Thousands who want jobs either try to see the President personally, or try to have "a friend" see him in their behalf. So great have office seeking calls on his minor matters. Of course, the office seeker still dogs the President's door and many who, as one quaint wit expressed it, "also icant to serve who only stand and wait" are still to be found in the White House. But if such an office seeker gets the President's ear he is apt to find a chilly atmosphere when he gets to the real While it is true that the President has no powers over Congress save such as are conferred upon him by the veto, the extra session call, appointments and the opinion of the people of the United States, it may nevertheless be said that his control of the Government is more absolute than his strictly legal powers might presuppose. More and more is this single man being considered by the American people as its Gov- As a matter of fact, the President has no power to introduce any bills into Congress. He can merely indicate to Congress by messages what his desires, opinions or feelings are in regard to any immediate legislation. But practically, having at his disposal Federal patronage which is of value to many Senators and Representatives, he frequently can ob- duct of that Government. If it were not for the provision which makes it necessary for the Senate to concur in Presidential appointees to the more important positions at his disposal he would be invested with a much vaster power than he actually is. Nevertheless, a tremendous quantity of Federal patronage is within the gift of the President and it is by the use of this patronage that he is frequently able to swing Congress into line with de- It will sound strange to many ears but the so-called Cabinet of the United States has no legal existence. The cabinet ministers of England are an integral part of the Government. The cabinet officers of the United States are but the heads of the several departments. • True, there is nothing in the Constitution or any law which restricts the President from making such free choice as he may desire of those gentlemen who stand at the head of the several great departments of the Government, but when they are called into conclave to advise with the President, they have no power whatever save as personal friends, giving their advice and opinions in matters which he may submit to An exception should be noted to the restricted powers of the President when a state of war exists. At such a time the Presidential power immediately swings to its maxi- Republicans, Democrats, Progressives, Prohibitionists, Socialists, men of every party and political faith, unite in support of the President in matters which concern the welfare of the country, and to this patriotic feeling and belief in the integrity of the holder of the Presidential office can be found the root of that power which the President enjoys in time of national stress. mum. As commander of the Army and Navy and charged with the welfare of the Nation, in time of war his powers may exceed those vested in any other luler in any country. The American people have aa immense reverence for the position of Chief Executive of the Nation, and any man who obtains that office is at once invested by all Americans with an authority and a dignity far beyond that of any other ruler. process is a prerogative of the House of Representatives. An impeached President is tried by the Senate sitting as a court with the Chief Justice of the Supreme Court of the United States presiding. Only one President of the United States has ever been impeached, Andrew Johnson, and the impeachment was not sustained. duct of the business of the United States Government, the President has a busy time with foreign relations. He must not only appoint all ambassadors and ministers to foreign countries, but he receives the Ambassadors of foreign countries to this nation and deals directly with those representatives of foreign governments and rulers. He has an enormous official and personal correspondence, the greater part of which, of course, is handled in a not yet been accomplished, but which has threatened on more than one occasion and may yet become a fact. There is nothing in the Constitution or the laws of the United States to forbid the continual re-election of one man to the Presidency. Still a third unwritten law is that popular opinion that the President must necessarily attend to business in the White House. A President is entitled, by lack of any restrictions to the contrary, to live in any part clerks in the White House. There are a number of unwritten laws in regard to the Presidency, most of them more honored in the breach than in the observance. One is to the effect that the President of the United States should not leave the United States during his term in office, a thing, however, which has been done. Another concerns the election of a President for more than two consecutive terms, a feat which has of the United States he desires and cannot be compelled by any power, other than that of public opinion, to remain in Washington or attend to business! He can take a vacation every day in the year if he wants and no one can call him to account save the House of Representatives by impeachment proceedings. The President of the United States is an extraordinarily busy man. Just how busy it is almost impossible for the uninitiated to appreciate. any citizen of the United States who has business with the President to see him, it is not possible for even a Senator or a member of the Cabinet to walk in upon the President uninvited. It is necessary for any one having business with the President to make an engagement in advance. At the beginning of every business day a slip of paper headed "The President's Engagements" is laid before the President showing exactly what he has or his secretary has agreed he shall do with his time. Such a Presidential engagement slip is reproduced herewith, and shows that from 10 :25 A. M. to 12:45 P. M., which is shortly before lunch, the President has engaged to see and tal?\. with sixteen different people. As a matter of fact, twenty-four hours is all too short for any President to get through the hundreds of routine and thousands of official matters which require his attention daily. No President has ever abused the confidence of the American people. All have been extremely hardworking men who took vacations and laid down their work only when their health absolutely required it. For the job of being President of the United States is perhaps the hardest individual piece of work which any man can possibly do and the reward of $75,000 a year and $25,000 for traveling expenses is far smaller than the responsibility of the position should demand. When it is considered that there are several men in this country drawing a salary of one million dollars a year or more for commercial work and any number of railroad presidents and presidents of corporations whose salaries exceed that of the President of the United States, it can well be understood how the principal emoluments of the office of Chief Executive are found in the honor and glory of directing the destinies of the greatest nation in the world, and not in any material reward which the position may bring. son of the President is always guarded with Secret Service attendants. If he goes to the theater — which the present occupant of the White House does often — he has, of course, his own box. Somewhere who precede him to the box and watch it from the rear and from the audience. If the President goes automobiling, a huge Secret Service car with U. S. S. S. on the rear, follows him. When out on the highroad, no car passes the Secret Service car and the White House car from the rear. If the President happens to want to travel at fifteen miles an hour, he may come into the city at the head of a procession of a hundred cars, all of them anxious to pass, but none of them able to get by the Secret Service car, the crew of whicii is taking uo The public reception — a relic of days when visitors to the Nation's Capitol were few and far between — is one of the trials of a President's life. He must learn to be more than expert in his greeting, or he will have a hand and arm incapacitated for work by the too cordial grasps of his admirers. Indeed, * often in small receptions to a visiting delegation or convention, attendants will quietly pass the word and request all visitors to be careful not to grip the President's hand hard. Perhaps no President who ever shook hands with five thousand people in an afternoon had this matter down to a finer science than President Roosevelt, whose method of shaking hands left the visitor nothing to do but grin and bear it; the firm and sudden grip was, of course, self-preservative. The President, nominally the head of Washington society, has little time for gayety, and the White House is not normally the scene of entertainment. Of course, official receptions to the Cabinet, and to members of Congress and to the Diplomatic Corps are necessary and frequent occurrences, but as a rule our Presidents have been too busy to indulge in those formal and elaborate functions more characteristic of older countries than one which is largely built on the idea of the value of time. States, in addition to his numerous duties as Chief Magistrate, finds time to be also President of the American Red Cross, ex-officio President of the Washington National Monument Society, patron ex-officio of the Columbia Institution for the Deaf, a Member of the Smithsonian Institution, Chairman of the Arlington Memorial Bridge Commission No nation in the world with any pretensions to size or importance houses its king, potentate, emperor, czar or president as poorly as the United States provides for its Chief Executive, and probably not until the Executive Mansion or White House crumbles to dust or burns to the ground will this condition be remedied. No President likes to say that what was good enough for Kinley is not good enough for him. President Roosevelt had the courage to add two wing-like structures to the White House, the one for the accommodation of visitors at the great White House receptions, the other to accommodate executive offices, clerks, files, etc., but with this exception the White House stands to-day what it has been for many years, a residence not comparable in size, beauty, convenience or utility with a dozen private residences in the Capitol City and thousands throughout the land. Built of Virginia freestone, and painted white since 1814 to conceal the marks of the fire which destroyed it when the British worked their will with the then struggling capital, the White House is to-day what it has always been — a two story structure but 170 feet long and 86 feet deep. It is beautiful with the beauty of simplicity; designed by James Hoban from the home of the Duke of Leinster near Dublin, it has architecturally satisfying lines, and the great portico with Ionic columns is not unimpressive. Moreover, the house is modernized inside, and has, of course, all modern conveniences of light, heat, ventilation, convenient kitchens, laundries, garage, servants' quarters, etc. But the fact remains that it is a relic of an age when the Government of the United States was on trial, when the tide which receded from the pomp and royalty of the mother country ran far up on the shores of simplicity and plain living, and that it is all out of keeping with the wonderful buildings now being constructed for the Government, and built by it for its own use in times past It is almost laughable to think of a two million dollar memorial to Lincoln — who so loved simplicity — and a shelter provided for the existing chief magistrate which would be dear at almost any price ! The White House is beautifully situated in extensive grounds, with a private and fenced-in park of its own to the rear as well as in front, in which are to be found many shade trees, plants of all sorts, fountains, a tennis court, etc. The White House is open to visitors at certain times, and any one can see the President who has a real reason for wanting to see him. But he is wvill guarded from annoyance or the mere seeker for sensation, and no one gets to him without running a gauntlet of guard, and clerk and secretary. President is both morally and legally supreme. While the Cabinet of the United States has no legal existence as such it has by custom become an integral part of the opinion in writing of the principal officer in each of the Executive Departments upon any subject relating to the duties of their respective offices." Later on, it says, "The Congress may by law vest the appointment of such inferior officers as they deem proper in the President alone, in the courts of law or the heads of the Departments." That is all the Constitution says of what is generally called the Cabinet. However, the President's choice of the heads of the various. Departments of the United States is rarely, if ever, questioned by the Senate, it being recognized that he has the right to call to his assistance men in whose judgment and wis- When the Cabinet meets, the President sits at the head of the table and the various cabinet members around it in the order of their seniority. It is generally supposed that questions are submitted to the Cabinet first for discussion and later that the Cabinet officers vote upon them. Such, of course, is not the case. The Cabinet acts in an advisory capacity only and has no power over the President in any way whatsoever. There is a story, probably apocryphal, of General Grant, who, when he and his Cabinet disagreed as to a certain policy, offered to put the matter to a vote. The President is reported to have Called upon his Cabinet members in turn, beginning with the Secretary of State. As each Cabinet member's name was called, he is said to have answered "Aye." When the President had finished he called his own name and gravely responded "No." Then he said to the assembled Cabinet officers, "There are seven votes in the affirmative and one in the negative and," here President Grant paused, "the negative vote is in the majority." Whereupon the President did as he had intended to do all along in spite of the advice of his officers ! In the event of any serious disagreement between a Cabinet officer and the President there is' only one course open and that is a resignation. Historic instances will occur to many. What is not so generally known, however, is that some Cabinet officers have to be asked to resign. Sometimes the asking is outright, as in a story told of Grant who made one of his Cabinet officers sit down at his own desk and dictated his resignation for him, and sometimes it is more gentle, as in the case of President McKinley and Secretary of War Alger. There was difference of opinion between President McKinley and his Secretary of War, and it is understood that it was not until a very vigorous hint had been given by those close to the President that Mr. Alger saw the light and tendered his resignation. The case of Mr. Ballinger is fresh in the public mind and students of politics, at least, will not need to be reminded that this gentleman stayed in office for some time after there was a decided degree of friction between him and the Chief Magistrate of the land. The President has a personal secretary, who in turn has many assistants. The job of being private secretary to the President of the United States is not, as one might think, that of an amanuensis. Rather has the office the dignity of a personal cabinet officer. The secretary to the President of the United States must be a man of great tact, ready memory, and have an able grasp upon political affairs. He is the one man about him whom the President must be in a position to trust absolutely, and the character of the many gentlemen who have prepared by the direction of the Secretary of State, which shows the enormous condensation necessary in a work of this kind. Vice-President die, the Secretary of State would become President. This really makes him the "Premier," although there is no official sanction for the title. before the Seal can be impressed The Department of State is of particular interest, in view of the fact that, after the Vice-President, the Secretary of State is the ranking official of the Government. In other words, should both the President and known as the Department of Foreign Affairs. By the act of September 15, 1789, the name of the department was changed to that of the Department of State, the principal officer thereof to be called the Secretary of State, and provision was made for the safe-keeping of the acts, records, and seal of the United States. STATES OF AMERICA The Department of State looks askance at any reproduction of the Great Heal and will never sanction its publication or use, but it will be found iu cyclopedias, dictionaries and atlases. So its publication here needs no apology, although a request to make a cut of a passport was denied the writer largely because the Great Seal was shown on it. When properly understood the seal should have the same respect as the flag. A committee was appointed on July 4, 1776, to prepare a Great Seal. posed to represent Congress. This all symbolizes the union and strength of the States preserved through the aid of Congress. The olive branch in the "dexter" talon represents peace, while the "sinister" talon holds thirteen arrows. In his beak is a scroll with the motto, "E Pluribus Unum" (one unity composed of many parts). What is above is called the "crest," but it is not really a crest at all, because the stars could not be tangibly represented as in nature, and attached to the top of a helmet, or could reasonably be represented as resting on a shield. The reverse, which has never been cut, consists of an unfinished pyramid. In the zenith is an eye in a triangle surrounded by a glory. On the base of the pyramid are the letters, '•MDCCLXXVI," and underneath the motto, "NOVUS ORDO 8ECLORUM" The members were Benjamin Franklin, John Adams and Thomas Jefferson. Several excellent designs were submitted, but Congress was not satisfied, so another committee was .appointed composed of Messrs. Middleton, Boudinot and Rutledge, and finally, on June 20, 1782, the Great Seal, as we now know, was adopted. It must be admitted that the heraldry is a little mixed, as might be supposed of the sturdy Americans who were far removed from the Heralds' College. A heraldic interpretation la dry and uninteresting, but in brief the sense is about as follows : The American Eagle bears on his breast an escutcheon composed of thirteen bars, supporting top, or a "chief," which is sup- ascribed to Virgil and others. In the early days the Secretary of State was charged with a multitude of duties, for under him all patents •were issued; but in 1849, the work of the Patent Office was turned over to the Department of the Interior. Copyrights were also under the direction of the Secretary of State, but in 1850 it was transferred to another department. The census en- AEE STILL Of EXISTENCE umeration was also under the charge of the Secretary of State In the early days. Certain matters relating to pardons were also under his jurisdiction, but in 1893 President Cleveland transferred such work to the Department of Justice. In 1856 a law was passed providing that the Secretary of State should be authorized to grant and issue passports, and to cause them to be granted and verified in foreign countries by diplomatic and consular officers, under such rules as the President might prescribe. THE DEPARTMENT OF STATE law, indicating the duties of the Secretary of State, is comprised in Section 202 of the Revised Statutes, reading as follows: "The Secretary of State shall perform such duties as shall from time to time be enjoined on or intrusted to him by the President relative to correspondences, commissions, or instructions to or with public ministers or consuls from the United States, or to negotiations with public ministers from foreign States or princes, or to memorials or other applications from foreign public ministers or other foreigners, or to such other matters; respecting foreign affairs as the President of the United States shrll assign to the department, and be shall conduct the business of the department in such manner as the President shall direct : Provided, That the Secretary of State may prescribe duties for the Assistant Secretaries, the solicitor, not interfering with his duties as an officer of the Department of Justice, and the clerks of bureaus, as well as for all the other employees in the department, and may make changes and transfers therein when, in his judgment, it becomes necessary. (June 20, 1874, vol. 18, p. 90.)" By the act of February 3, 1887, the Secretary of State was charged with the duty of certifying to the two Houses of Congress, and with the publication in some newspaper, of the Presidential election returns. Among the other duties of the Secretary of State might be mentioned the communication and correspondence of the President with the governors of the States and the attestation of all presidential proclamations, together with the publication of the laws and the Statutes at Large in the United States, embracing all acts of Congress, all proclamations issued by the President, all treaties between the United States and foreign nations, including postal conventions, and all concurrent resolutions of the two The compensation of the Secretary of State, under the act of September 11, 1789, was $3,500; under the act of February 20, 1819, it was raised to $6,000; in 1853, increased to $8,000; and under the act of March 4, 1911, increased to $12,000. In 1909 the question of reorganization was taken up, and it was found necessary to modernize and otherwise make for efficiency. This was caused by a number of reasons. The foreign trade of the country had been growing at an enormous extent. The people, endeavoring to market their manufactured products abroad, found themselves engaged in competition with the highly developed industries of England, France, Germany, and other countries; they were brought face to face, not only with the questions of tariffs and customs administration, but also with the need of that measure of diplomatic and consular support enjoyed by their competitors. The war with Spain had marked a new epoch in the history of American foreign relations. The American people, after having been regarded for many years as a stay-at-home nation, absorbed in the development of their own resources, had suddenly been recognized to have assumed a new position among nations, so that it would be thenceforth impossible for this Government to escape the responsibilities of being one of the great forces in international affairs, and of taking a more prominent part in discussions and deliberations concerning matters of international importance. Consequently the Department of State had been called upon to deal with a multitude of questions with which, before the Spanish war, it had not been concerned. The Hague conferences, the adjustment of boundaries and other questions between the United States and Mexico and Canada, the arbitration of disputed questions with Canada and other nations, the negotiation oJ treaties to meet new conditions arising from the growth of the foreign interests of our people, the efforts of the United States to improve the conditions in Central America, the constantly increasing number of questions arising from the development of Mexico, and the adjustment of difficulties and protection of the interests of nearly 40,000 of our citizens who had temporarily taken up their residence and invested nearly $1,000,000,000 of American money in that country, the reorganization and improvement of the Diplomatic and Consular Services, and the increasing demand of the public upon those organizations — all these things and others had thrown upon the Department of State a mass of correspondence and a great number of questions for determination or discussion entirely beyond its ability to treat efficiently with the then existing equipment. Every immigrant coming to this country, and every American going to a foreign country, increases, in one way or another, the possibility of work for the Department of State. The inadequacy of the force of the Department became critical, and a tentative reorganization of the Department upon modern lines, with a view to a maximum degree of efficiency, was then effected. The Secretary of State is peculiarly the adviser of the President, especially those points involving broad questions of general policy, and the Secretary of State is also responsible for the conduct of foreign relations, and, in addition to the time required for the study of important diplomatic questions, he receives the representatives of foreign governments for the discussion of diplomatic business and is in touch with matters affecting treaties with the Committee on Foreign Relations of the Senate. The Assistant Secretary, who receives a salary of $5,000 a year, does not specialize, but must be prepared to be in close touch with all the larger questions of foreign policy, and relieve the Secretary, as far as possible, of a portion of the general work. This is a very responsible position in the Department. The Second Assistant Secretary is assigned to the detailed treatment by the departmental and diplomatic services of current diplomatic and political questions, except such special matters as may, from time to time, be assigned the Counselor. It is his duty to direct the activities of all the bureaus and divisions in respect to the diplomatic questions that are constantly arising all over the world, and to examine and approve the correspondence in respect to such matters prepared for the signature of the Secretary or the Acting Secretary. His salary is $4,500 a year. The administrative direction of the Diplomatic Service, as distinguished from the treatment of subjects of international intercourse, is delegated to the Third Assistant Secretary of State. He is responsible for the maintenance, upkeep, and expenditures for that service. He also directs the treatment of all questions in relation to international congresses, conferences, commissions, expositions, and ceremonial matters, and has the supervision of the Division of Western European Affairs. He is charged with the approval or disapproval of expenditures of public moneys in the department and the foreign service. His salary is $4,500 a year. * sular Service and the direction of its activities in connection with the promotion and extension of our foreign commerce is delegated to the Director of the Consular Service, who has immediate control of expenditures for the maintenance of that organization. He is also charged with the study and treatment of such special subjects as may, from time to time, be assigned to him by the Secretary and the Assistant Secretary of State. He also receives $4,500 per annum. The Chief Clerk has the direction of the internal business of the department, of the clerical force, the methods of transacting business, including the receipt and transmission of mail, the purchase of supplies, etc. His compensation is $3,000 a year. Generally speaking, the questions of law, international or municipal, which may be involved in the determination of matters brought before the department, are referred to the Solicitor's office. The result is, that the scope of the work coming before the office is very broad, including questions of constitutional law, admiralty law, criminal law, the law of torts, contracts, etc., and, of course, all branches and fields of international law. The more important of the matters which actually come before the office for determination are as follows : Western European affairs There are also translators, assistant solicitors, law clerks, private and confidential secretaries, as well as dispatch agents in New York, San Francisco, New Orleans and brary are contained some of the most valuable documents concerning our history, including the Declaration of Independence, Continental Congress records, and historical manuscripts of all kinds. cule the American Consular Service, holding up to scorn the comic opera creation who held the center of the stage with his palmleaf fan and slow drawl as the prototype of a consular officer. In the distant past there may have been an occasional officer who lived down to this popular conception, but it is so no longer. The modern Consular Service had its inception in the days of Grover Cleveland, although it was Theodore Roosevelt who put it upon its present firm, non-political and" non-partisan basis, with merit and merit only as the cause for advancement. Since then it has grown in efficiency and size until to-day it is unrivaled. In the past good results from the Consular Service were Infrequent because of the method of appointment of consular officers without regard to their particular fitness for the places to which they were sent, or as the former Secretary of State, Mr. Root, expressed it, "The placing of round pegs in square holes." Since 1896, when the first order providing for an examination before appointment went into effect, the Service has been strengthened and improved until those who knew it in the old days can no longer recognize it. Men who pass an examination for a Consular position to-day have to know a variety of things and know them well. Examinations are both oral and written, the two counting equally. The oral examination determines the -candidate's business ability, alertness, general contemporary information, and natural fit- ness for the service, including moral, mental and physical qualifications, character, address and general education and good command of English. The written examination includes French, German or Spanish; the natural, industrial and commercial resources and the commerce of the United States, especially with reference to possibilities of increasing and extending the foreign trade of the United States; political economy and the elements of international, commercial and maritime law, American history, government and institutions ; political and commercial geography ; arithmetic (as used in commercial statistics, tariff calculations, exchange, accounts, etc.) ; the modern history, since 1850, of Europe, Latin-America and the Far East, with particular attention to political, commercial and economic tendencies. After passing a stiff examination and getting an appointment, young consular officers go to school in Washington, at a "model -consulate" in the Consular Bureau at the State Department. Every newly appointed consul is required to proceed to Washington and spend at least thirty days in this school learning just what he will be expected to do when he reaches his post, and how he may get the best results from whatever conditions confront him. Although this special form of training has been in force but a comparatively short time it is showing its good effect by the improvement in the work and reports of the consular officers, and by the attitude of appreciation and understanding of their duties which the consuls display as a result of the instructions. , A consular officer has no duty of greater importance than that of service to his countrymen. The splendid service rendered by United States consular officers in the field of the great war now raging is well known, and none of the unfortunates who were helped in Berlin, London, Paris and Belgium by our Consuls General, consuls and consular agents will ever forget the service they received. Some of the accompanying pictures show how great was the pressure on the consulates of the great neutral nation in the countries at war, where citizens of the enemy clamored for help, relief, passports, and the hundred and one things that only a trained, hard working and disinterested staff could do. Important as such services are, they are, luckily, not often required. Nor is the gathering and transmittal of commercial information, important though that duty is, the whole work of a consular officer. Only when reading a list of his duties is it easy to comprehend why those who fill such positions mrst be highly educated and alert men. For instance, a consular officer must maintain and promote all interests of American citizens. He is required to protect them in all privileges provided by treaty or conceded by usage ; to vis£ and, when so authorized, to issue passports; when permitted by treaty, law or usage, to take charge of and settle the personal estates of Americans who may die abroad, without legal or other representatives, and remit the proceeds to the Treasury in case they are not called for by a legal representative within one year; to ship, discharge, and, under certain conditions, maintain and send American seamen to the United States; to settle disputes between masters and seamen of American vessels ; to investigate charges of mutiny or insubordination on the high seas and send mutineers to the United States for trial ; to render assistance in the case of wrecked or stranded American vessels, and, in the absence of the master or other qualified person, take charge of the wrecks and cargoes, if permitted to do so by the laws of the country; to receive the papers of American vessels arriving at foreign ports and deliver them after the discharge of the obligations of the vessels toward the members of their crews, and upon the production of clearances from the proper foreign port officials; to certify to the correctness of the valuation of merchandise exported to the United States where the shipment amounts to more than $100; to act as official witnesses to marriages of American citizens abroad; to aid in the enforcement of the immigration laws, and to certify to the correctness of the certificates issued by Chinese and other officials to Chinese persons coming to the United States ; to protect the health of our seaports by reporting weekly the sanitary and health conditions of the port at which he resides, and by issuing to vessels clearing for the United States bills of health describing the condition of the ports, the vessels, crews, passengers and cargoes; and to take depositions and perform other acts which public notaries in the United States are authorized or required to perform. In addition to the foregoing duties, consular officers in China, Turkey, Siam, Muskat, Morocco, and a few other so-called non-Christian countries, are invested with judicial powers over American citizens in those countries. These powers are usually denned by treaty, but generally include the trial of civil cases to which Americans are parties, and in some instances extend to the trial of criminal cases. in the nine classes. The consular officer in London, Paris or Berlin lives a busy, active and civilized life. But in either event he is a willing servant of his country and doing for it a work beyond computation in price, although it is a fact that fees collected for the multitudinous services he renders almost equal the cost of the service. All fees received by any officer in the consular service for services rendered in connection with the duties of his office or as a consular officer, including fees for notarial services, and fees for taking depositions, executing commissions or letters rogatory, settling estates, receiving or paying out moneys, caring for or disposing of property, are paid into the Treasury of the United States. The only compensation of officers is their salaries, except in the case of consular agents. Consular agents are paid one half of the fees received in their offices, up to a maximum sum of one thousand dollars in any one year, the other half being paid into the Treasury. The fees collected do not nearly equal the .expenditures of the service. Fees for a deposition may run to $100, depending on its length. The illustrations on page 481 show two types of consulates in far countries— the handsome residence at Cairo, Egypt, contrasted with the mud-roof dwelling in far off Turkey. But the type of dwelling makes little difference to its occupant — he is there to serve, to open the markets of his country to American manufacturers, and to serve Americans in need or in distress. Indeed, he does more than serve his own countrymen — not infrequently he serves the merchants of the country to which he is sent. documents published from the letters sent in to the Consular Bureau of the State Department — contain vital information regarding trade conditions in all countries. How valuable these are was well brought out recently in a published interview with the president of the Sheffield (England) Chamber of Commerce. It seems that certain Sheffield manufacturers had sudden need to know the sources and distribution throughout the world of .wolfram ore, from which tungsten, essential in the manufacture of high-resistance steel for guns and armor, is made. The president of the Chamber of Commerce was unable to It in the reports of American consuls, did find it there. I discovered where wolfram was produced ; the quality, state of the trade and amount available. That information assisted materially in bringing about the manufacture of tungsten powder in this country, which, although started during the war, has been a magnificent success and will be a great success after the war." has risen from the ranks in his twenty years of service, called attention recently to a unique feature of America's system, which is one reason why it is so efficient This is the system of inspection. Speaking of it, Mr. Carr said : "In this field we have been pioneers. The law of 1906 created five so-called consul generals at large. Each travels over a grand division of the world, inspecting each consular office once every two years. The Department of State is enabled by this means not only to detect and rectify irregularities in the work of individual consuls, but to enforce uniformity of method and organization. If a consular officer in a faroff corner of the globe, by inspiration or careful thought evolves an improved method of performing some routine duty or discovers a new and effective way by which the foreign trade of the United States may be promoted, this is discovered by the inspector on his next visit and if found good in every way, communicated to the Department of State, and by it to the other consuls at large, with the result that all which is best in individual offices and in the practices of individual officers becomes eventually the common property of the service. Other governments recognize the practical value of this inspection system. Great Britain has undertaken something analogous in a tentative way and the French foreign office has a like project under consideration." The Secretary of State is charged, under the direction of the President, with the duties appertaining to correspondence with the public ministers and the consuls of the United States, and with the representatives of foreign powers accredited to the United States ; and to negotiations of whatever character relating to the foreign affairs of the United States. He is also the medium of correspondence between the President and the chief executives of the several States of the United States ; he has the custody of the Great Seal of the United States, and countersigns and affixes such seal to all Executive proclamations, to various commissions, and to warrants for the extradition of fugitives from Justice. He is regarded as the first in rank among the members of the Cabinet. He is also the custodian of the treaties made with foreign states, and of the laws of the United States. He grants and issues passports, and exequaturs to foreign consuls in the United States are issued through his office. He publishes the laws and resolutions of Congress, COUNSELOR The Counselor becomes the Acting Secretary of State in the absence of the Secretary. He is charged with the supervision of such matters and the preparation of such correspondence as may he assigned to him by the Secretary. ASSISTANT SECRETARIES OF STATE Under the organization of the department the Assistant Secretary, Second Assistant Secretary and Third Assistant Secretary are charged with the supervision of all correspondence with the diplomatic and consular officers, and are intrusted with the preparation of the correspondence upon any questions arising in the course of the public business that may be assigned to them by the Secretary. DIRECTOR OF THE CONSULAR SERVICE The Director of the Consular Service is charged with the general supervision of the Consular Service and such other CHIEF CLERK The Chief Clerk has general supervision of the clerks and employees and of departmental matters ; charge of the property of the department. FOREIGN TRADE ADVISER General supervision of foreign trade matters ; diplomatic and consular correspondence and miscellaneous correspondence relating thereto. DIPLOMATIC BUREAU Diplomatic correspondence and miscellaneous correspondence relating thereto. DIVISION OF LATIN-AMERICAN AFFAIRS Diplomatic and consular correspondence, on matters other than those of an administrative character, in relation to Central America, Panama, South America and the West Indies. DIVISION OF MEXICAN AFFAIRS Diplomatic and consular correspondence, on matters other than those of an administrative character, in relation to Mexico. Diplomatic and consular correspondence, on matters other than those of an administrative character, in relation to Japan, China, and leased territories, Siberia. Ilong-kong, French Indo-China, Siam, Straits Settlements, Borneo, East Indies, India, and in general the Far East. Diplomatic and consular correspondence, on matters other than those of an administrative character, in relation to Germany, Austria-Hungary, Russia, Roumania, Servia, Bulgaria, Montenegro, Turkey, Greece, Italy, Abyssinia, Persia, Egypt, and colonies belonging to countries of this series. AFFAIRS Diplomatic and consular correspondence, on matters other than those of an administrative character, in relation to Great Britain (Canada, Australia, New Zealand, and British colonies not elsewhere enumerated), Portugal, Spain, France, Morocco, Belgium, the Kongo, Switzerland, Norway, Sweden, the Netherlands, Luxemburg, Denmark and Liberia. CONSULAR BUREAU Consular correspondence and miscellaneous correspondence relating thereto, and administrative matters relating to the consular service. BUREAU OF APPOINTMENTS Custody of the Great Seal and applications for office, and the preparation of commissions, exequaturs, warrants of extradition, Departmental Register, diplomatic and consular lists and consular bonds ; correspondence and other matters regarding entrance examinations for the foreign service. BUREAU OF CITIZENSHIP Examination of applications for passports, issuance of passports and authentications ; receiving and filing duplicates of evidence, registration, etc., under act of March 2, 1907, in reference to expatriation of citizens and their protection abroad ; keeping of necessary records thereunder ; conduct of correspondence in relation to the foregoing. BUREAU OF ROLLS AND LIBRARY Custody of the rolls, treaties, etc. ; promulgation of the laws, treaties, Executive orders and proclamations ; care and superintendence of the library and public documents ; care of papers relating to international commissions. DIVISION OF INFORMATION The preparation and distribution to the foreign service of diplomatic, commercial and other correspondence and documents important to their information upon foreign relations ; editing "Foreign Relations" of the United States. OFFICE OF THE LAW CLERK Editing and indexing the laws, resolutions, public treaties and proclamations for publication in the Statutes at Large. SUPERINTENDENT OF BUILDING The superintendent of the State, War and Navy Department Building is the executive officer of the commission created by Congress, consisting of the Secretaries of State, War and Navy, for the government of this building. He has charge of, care, preservation, repairing, warming, ventilating, lighting and cleaning of the building, grounds and approaches, and disburses the special appropriations for this purpose; he has charge of all the employees of the building proper, and appoints them by direction of the Secretaries. grants warrants for all moneys drawn from the Treasury in pursuance of appropriations made by law, and for the payment of moneys into the Treasury; and annually submits to Congress estimates of the probable revenues and disbursements of the Government. He controls the construction and main- tenance of public buildings, the coinage and printing of money, the administration of the Coast Guard and the Public Health branches of the public service. He is ex-officio chairman of the Federal Reserve Board created by act approved December 23, 1913, known as the There are three Assistant Secretaries in charge of the bureaus and divisions of the Treasury Department. One has charge of Public Health Service, Supervising Architect's Office, the selection of sites for public buildings, Coast Guard, Appointment Division, General Supply Committee, Section of Surety Bonds and all unassigned business of the Department. To the Assistant Secretary in charge of fiscal bureaus is assigned general supervision of all matters relating to the Office of the Comp- States, the Bureau of Internal Revenue, the Bureau of the Mint, the Office of the Comptroller of the Treasury, the Auditors of the several departments, the Register of the Treasury, the Bureau of Engraving and Printing, the Division of Bookkeeping and Warrants, the Division of Loans and Currency, the Division of Mail and Files, the Division of Printing and Stationery, the Division of Public Moneys, the Secret-Service Division, the Federal Farm Loan Board, and the Office of the Disbursing Clerk. charge of customs is assigned the general supervision of the Division of Customs, of all matters pertaining to the Customs Service, and the Bureau of War-Risk Insurance, as referred to later on. The chief clerk is the chief executive officer of the Secretary, and, under the direction of the Secretary and Assistant Secretaries, is charged with the enforcement of departmental regulations general in their nature; is by law superintendent of the Treasury Building and other related buildings and rolling stock belonging to the department ; the direction of engineers, watchmen, firemen, etc., connected with the maintenance and protection of the Treasury buildings, etc. ; the expenditure of appropriations for contingent expenses ; the administrative control of appropriations made for Government exhibits at various expositions ; the supervision and general administration of the General Supply Committee ; handles offers in compromise cases ; the custody of the records, files and library of the Secretary's office ; the custody of all sites for proposed buildings in Washington; the checking of all mail relating to the personnel of the Treasury Department; the handling of requests for certified copies of official papers, and the charge of all business of the Secretary's office which is not otherwise assigned. • COMPTROLLER OF THE CURRENCY The Comptroller of the Currency is the chief officer of that bureau of the Treasury Department which is charged with the execution of all laws passed by Congress relating to the issue and regulation of the national currency, generally known as national bank notes, secured by United States bonds ; and under the supervision of the Federal Reserve Board Is also in charge of the issue vision over all national banks throughout the United States, including Alaska and Hawaii, in the matter of their organization and regulation. He is vested with the power to appoint receivers and to enforce penalties prescribed for SEPAKATING CHAEEED BANK BILLS ^ violations of the national bank act. Under the Federal Reserve act he executed and issued the certificates or charters for tht Federal Reserve banks. The Comptroller of the Currency is ex officio a member of the Federal Reserve Board. Reports of condition of all national banks are made to the Comptroller not less frequently than five times a year, by the banks, and also His powers are exercised under the general supervision of the Secretary of the Treasury, but under the law his annual report is made direct to Congress ; all other bureaus of the Treasury Department report to Congress through the Secretary of the Treasury, and these reports are printed. Treasury, countersigned by the Comptroller of the Treasury, and not otherwise. He takes receipts for all moneys paid by him and gives receipts for all moneys received, and all receipts for moneys received by him shall be endorsed upon warrants signed by the Secretary of the Treasury, without which warrant so money received into the public Treasury shall be valid. He renders his accounts to the Comptroller of the Treasury quarterly, or oftener if required, and transmits copies thereof, when settled, to the Secretary of the Treasury. The moneys in his hands are at all times subject to the inspection of the Secretary of the Treasury and the Comptroller of the Treasury. The Treasurer makes a report to the Secretary of the Treasury every 30th of June, showing the condition of all of the several accounts. The Commissioner of Internal Revenue has general superintendence of the collection of all internal-revenue taxes, the enforcement of internal-revenue laws, appointment of internal-revenue em- ployees, compensation and duties of gaugers, storekeepers and other subordinate officers ; the preparation and distribution of stamps, instructions, regulations, forms, blanks, hydrometers, stationery, etc. of the country, of which two, located at New Orleans, La., and Carson City, Nev., now operate only as Assay Offices. The Mints now engaged in coinage operations are located at Philadelphia, San Francisco and Denver, that at Philadelphia being the largest. In addition to the Assay Offices located at New Orleans, La., and Carson City, Nev., the Government maintains six others, located at New York City, Seattle, Wash.; Deadwood, S. D. ; Boise, Idaho ; Salt Lake City, Utah, and Helena, Montana. The headquarters of the Mint Service are in the Treasury Department, Washington, D. C., known as the Bureau of the Mint. This consists of the office of the Director of the DEPARTMENT OF THE TREASURE Mint, an assay laboratory for the purpose of testing the weight and fineness of the coins made at the several mints, and a clerical force which, under the Director of the Mint, reviews the accounts of the various institutions, prepares for publication, quarterly, an estimate of the value of the standard coins of foreign countries for custom house and other public purposes, and works up the statistical data for the annual report of the Director on the operations of the Mint Service for the fiscal year, including also statistics of the production of precious metals in the United States and the world for the calendar year. ceipts of the precious metals to the Mints to be coined. Much of the metal is not suitable for immediate coinage, and refineries are maintained at the Mints at San Fraucisco and Denver and the Assay Oflace at New York City to purify the metal. Such of it as may be needed for coinage is then alloyed with copper, the proportions being nine parts of gold or silver to one part of copper, making what is known as 900 fine or "standard" metal, which has been found most suitable for coins, the pure gold or silver being comparatively soft, and subject to appreciable abrasion or wear. Minor coins are manufactured from nickel and bronze, the MONEY OF ALL KINDS IS TRANSPORTED IN HEAVILY GUARDED TRUCKS The Mints and Assay Offices have been established in localities suitable for the convenient acquisition of gold and silver by the Government for the purpose of coinage. Gold and silver bullion is received and paid for at its exact valuation (the price of gold remaining stationary, while that of silver fluctuates) and the Assay Offices forward their re- quired. As the stock of gold in the country has accumulated far beyond the needs for that metal as a circulating medium, it has been found most convenient and economical, after filling the yearly demands for new gold coin, to melt the balance of this precious metal into bars of uniform and convenient size, to be stored in the vaults of the mints and held as a reserve against which gold certificates may be issued. New coin usually gets into circulation through the Disbursing Office of the Treasury Department and banking institutions in exchange for the larger denominations of money. all of the domestic coin, but also the coinage for the Philippine Islands and, as their business permits, such of the coinage of adjacent countries as it is found expedient and practicable to handle. At the Philadelphia Mint there is maintained a complete engraving and medal-making establishment, where are manufactured all dies used in the domestic and Philippine coinage, and also dies and medals of a national character. The Comptroller of the Treasury, under the direction of the Secretary of the Treasury, prescribes the forms of keeping and rendering all public accounts except those relating to postal revenues and the expenditures therefrom. He is charged with the duty of revising accounts upon appeal from settlements made by the auditors. Upon the application of disbursing officers, the head of any executive department, or other independent establishment not under any of the executive departments, the Comptroller is required to render his advance decision upon any question involving a payment to be made by them or under them, which decision, when rendered, governs the auditor and the Comptroller in the settlement of the account involving the payment inquired about. He is required to approve, disapprove, or modify all decisions by auditors making an original construction or modifying an existing construction of statutes, and certify his action to the auditor whose duties are affected thereby. Under his direction the several auditors superintend the recovery of all debts finally certified by them, respectively, to be due the United States, except those arising under the Post Office Department. He superin- tends the preservation by the auditors of all accounts which have been finally adjusted by them, together with the vouchers and certificates relating to the same. He is required, on his own motion, when in the interests of the Government, to revise any account settled by any auditor. In any case where, in his opinion, the interests of the Government require, he may direct any of the auditors forthwith to audit and settle any particular account pending before the said auditor for settlement. It is his duty to countersign all warrants authorized by law to be signed by the Secretary of the Treasury. The Register of the Treasury signs all bonds of the United States, the bonds of the District of Columbia, the Philippine Islands, the city of Manila, the city of Cebu, and the Porto Rican gold loans, and keeps records showing the daily outstanding balances thereof. He certifies to the Treasurer of the United States, the Auditor for the Treasury, and the Loans and Currency Division, Secretary's Office, the in- terest due on United States at interest periods ; also gives an administrative examination to paid interest checks received from the Treasurer, and transmits the same to the Auditor for the Treasury. He examines and records all paid interest coupons and all other United States securities redeemed, and keeps records of the outstanding principal and interest of the bonded indebtedness of the Government. Printing designs, engraves, prints and finishes all of the securities and other similar work of the Government, embracing United States notes, bonds, and certificates, National Bank notes, Federal Reserve notes, internal-revenue, postage and customs stamps, Treasury drafts and checks, disbursing officers' checks, licenses, commissions, patent and pension certificates, and portraits authorized by law of deceased Members of Congress and other public officers; also all postage stamps and all securities issued by the Bureau of Insular Affairs to our insular possessions. ued as the United States Marine Hospital Service until July 1, 1902, when Congress changed the name to that of the Public Health and Marine Hospital Service of the United States. The act approved August 14, 1912, further changed the name of the Service to that of the Public Health Service, and greatly increased its powers and functions. As originally created the United States Marine Hospital Service had for its function the medical and surgical relief of the sick and injured seamen of the merchant marine and the Navy. The organic act placed the Marine Hospital Service in the Treasury Department, where it has continued to remain as a bureau. The organic act was amended by the acts of March 2, 1799, May 5, 1802, February 26, 1811, and July 29, 1870. As at present organized the Bureau of the Public Health Service is situated at Washington, D. C., and comprises seven divisions, the operations of which are co-ordinated and each under the immediate supervision of the Surgeon General. An Assistant Surgeon General is in charge of each of these divisions, excepting the miscellaneous division. f i Through the Division of Marine Hospitals and Relief professional care is taken of sick and disabled seamen at twenty-two marine hospitals and one hundred and twentythree other relief stations. The bene' ficiaries include officers and crews of registered, enrolled, or licensed vessels of the United States and of the Coast Guard and Lighthouse Ser- vice; seamen employed on vessels of the Mississippi River Commission, and of the Engineer Corps of the Army; keepers and surfmen of the Coast Guard. A purveying depot for the purchase and issuance of supplies is maintained at Washington. Physical examinations of officers and seamen and keepers and surfmen of the Coast Guard and the examinations for the detection of colorblindness in masters, mates, and pilots are conducted through this division, and the medical evidence of disability in claims for benefits against the Coast Guard are reviewed. Through the Division of Domestic (Interstate) Quarantine is enforced Section 3 of the act of February 15, 1893, relating to the prevention of the spread of contagious or infectious diseases from one State or Territory into another. The control of the interstate spread of disease is effected by the Interstate Quarantine Regulations, compiled by this division. These regulations prohibit the carrying of persons afflicted with contagious diseases by interstate carriers and provide the conditions under which certain other infected persons may be transported. They provide that the vehicles of these carriers be maintained in a sanitary condition and that water furnished thereon shall conform to the bacteriological standard for drinking water supplied to the public by common carriers in interstate traffic as adopted by the Treasury Department on October 21, 1914. For the enforcement and administration of these regulations the country has been divided into twelve Interstate Sanitary Districts, each under the direction of this division. Laboratories have been established at central cities in these districts and an officer of the Public Health Service placed in each. The education of the general public in hygiene and sanitation is conducted by the Domestic Quarantine Division by means of lectures, the loan of stereopticon slides to physicians, welfare workers, educators, etc., by exhibits, such as at the Panama Pacific International Exposition and on the Government Safety First Train, and by press items issued to about 8,000 newspapers. Sanitary and relief work in Alaska, hospitals and sanitary work at international exposi- ing thereto. He has control of fiftyfive Federal quarantine stations in the United States, and others in the Philippines, Hawaii, and Porto Rico, and supervises the medical officers detailed in the offices of the American consular officers at foreign ports to prevent the introduction of contagious or infectious diseases into the United States. Under section 17 of the act approved February 20, 1907, he has supervision over the EXAMINING AN ALIEN AT ELLIS ISLAND BY MENTAL TESTS tions, inspection of Government buildings for sanitary defects, and the important duty of the suppression of epidemics come within the scope of this division. Through the Division of Foreign and Insular Quarantine and Immigration the Surgeon General enforces the national quarantine laws and prepares the regulations relat- arriving aliens. In the Division of Personnel and Accounts are kept the records of the officers and of the expenditures of the appropriations. The Division of Sanitary Reports and Statistics collects and publishes information regarding the prevalence and geographic distribution of diseases dangerous to the public health in the United States and foreign countries. Court decisions, laws, regulations, and ordinances pertaining to the public health are compiled, digested and published. Its publications contain articles on subjects relating to the public health. This division issues the Public Health Reports (weekly) and Supplements to, and Reprints from, the Publi<* search conducts the scientific investigations of the service. Intensive studies of diseases of man, including hookworm diseases, malaria, pellagra, trachoma, typhoid .fever, and tuberculosis, of school, mental, and industrial hygiene, of rural sanitation, of public health administration, of water supplies and sewage, and of coastal waters are carried on from special headquarters in the field in co-operation with State and local health authorities. Technical and purely laboratory studies are conducted at the Hygienic Laboratory in Washington, at special field laboratories, and at the leprosy investigation station in Hawaii. Information thus obtained is disseminated through publications, correspordence, lectures, and confer- ences with health authorities concerning the results of field studies in their jurisdictions. Through the division the department enforces the act of July 1, 1902, "to regulate the sale of viruses, serums, etc." The Surgeon General is required by law to call an annual conference of State and territorial health authorities, and special conferences may also be called at any time. For advice in respect to scientific investigations he may convene the advisory board of the Hygienic Laboratory. vision the various service publications are issued, including the annual reports, public health reports, supplements, and reprints, public health bulletins of the Hygiene Laboratory, and miscellaneous publications on health topics. United States Public Health Service on July 1, 1916, consisted of the Surgeon General, 6 Assistant Surgeon Generals, 1 Assistant Surgeon General at large, 13 senior surgeons, 72 surgeons, 37 passed assistant surgeons, and 70 assistant surgeons. In addition there are scientific assistants, consisting of acting assistant surgeons, epidemiologists, internes at marine hospitals, pharmacists, etc. the Coast Guard is charged by law with the administration of the Coast Guard, under the direction of the Secretary of the Treasury. Headquarters are located at the Treasury Department The act of January 28, 1915, provided that the Coast Guard be created in lieu of the then existing Revenue-Cutter Service and the Life-Saving Service, and to be composed of those two organizations. It also provided that it shall constitute a part of the mili- tary forces of the United States, and shall operate under the Treasury Department in time of peace and as a part of the Navy, subject to the orders of the Secretary of the Navy, in time of war, or when the President shall so direct. In general the duties of the Coast Guard may be classified as follows: Rendering assistance to vessels in distress and saving life and property; destruction or removal of wrecks, derelicts, and other floating dangers to navigation ; extending LONGITUDE 49.36 WEST medical aid to American vessels engaged in deep-sea fisheries ; protection of the customs revenue; operating as a part of the Navy in time of war or when the President shall direct ; enforcement of law and regulations governing anchorage of vessels in navigable waters; enforcement of law relating to quarantine and neutrality ; suppression of mutinies on merchant vessels; enforcement of navigation and other laws governing merchant vessels and motor boats ; enforcement of law to provide for safety of life on navigable waters during regattas and marine parades ; protection of game and the seal and other fisheries in Alaska, etc. ; enforcement of spongefishing laws. following divisions : Division of Operations — Having cognizance of matters relating to the personnel and operations of the service. Division of Material — Having cognizance of matters relating to supplies, outfits, equipment, accounts, and the files. relating to the construction of and repairs to the hulls of vessels and boats, stations, wharves, and all other property. Division of Engineering — Having cognizance of matters relating to the construction of and repairs to the motive power of vessels and boats and the machinery of all other property. Division of Inspection — Having cognizance of matters relating to the inspection of vessels, stations, boats, and all other property. Under the direction of the Captain Commandant statistics are prepared regarding the loss of life and property on account of wrecked vessels in American waters. He is also required to acquaint himself, as far" as practicable, with all means employed in foreign countries which may seem to affect advantageously the interests of the Coast Guard, and to cause to be properly investigated all plans, devices, and inventions for the improvement of lifesaving apparatus for use at the" stations which may appear to be meritorious and available. This is accomplished through the medium of the Board on Life-Saving Appliances, which meets annually at Boston, Mass., for that purpose. OFFICE OF THE SUPERVISING ARCHITECT Under the direction of the Secretary of the Treasury, the Supervising Architect acquires the sites and designs, constructs, equips, supplies, operates and repairs United States public buildings generally, marine hospitals and quarantine stations, and wharves, bridges, roads, sewers, etc., in connection therewith. When specially authorized by law plans are obtained by competition among private architects. The Supervising Architect's Office was organized in 1853. Until 1861 an Army Engineer had charge of construction work ; since then Supervising Architect in sole charge. Present organization : Supervising Architect, the Executive Officer, directing the administrative phases of the work and in charge of the Accounts, Maintenance, Repairs, and Files and Records Divisions, and Custodians' and Janitors' field force; the Technical Officer, directing the architectural and engineering work and in charge of the Drafting, Structural, Mechanical and Electrical Engineering, and Computing Divisions, Public Information Room, Duplicating and Photograph Galleries, and the Construction field force. Board of Award, composed of Supervising Architect, Executive Officer, Technical Officer and Superintendent of Drafting Division, passes upon and recommends all important expenditures (except for land). Building work usually done by contract. Furniture and supplies generally obtained from manufacturers upon blanket annual contracts. Awards are to lowest best bidder, after advertising and public opening of bids. Supervising Architect approves materials and performance. Materials are tested by the National Bureau of Standards. Department orders land purchases and all expenditures from $500 upwards. Funds disbursed from Washington mainly. Each project supervised by resident superintendent ; each finished building in charge of custodian. Operating force and field force overseen by traveling inspectors. In 1853 the Supervising Architect had charge of 15 completed buildings and 28 to be constructed. In 1916 there are 1,073 completed public1 buildings, branch mints, assay offices, marine hospitals and quarantine stations; 117 separate projects under construction, 301 projects authorized, but not yet under construction; and 164 sites only (acquired or to be acquired) for which no buildings have yet been authorized. The present headquarters force (quartered on the top floor of the Treasury Building) numbers 246. Field forces: Construction, 124; Operating force, about 5,000. The whole force of architects, engineers, draftsmen, computers, superintendents, inspectors, lawyers, accountants, stenographers, clerks, mechanics, janitors, etc., is within the classified civil service. ance was created by Act of Congress on September 2nd, 1914, to cover American vessels and their cargoes against the risks of war. It was to expire September 2nd, 1916, but on August llth, 1916, was extended for a period of one year. During the two years of this Bureau's existence it has covered war risk insurance on many vessels and cargoes where the market was small and without the assistance which was granted by the Bureau many of these vessels could not have sailed. From September 2nd, 1914, to September 2nd, 1916, the Bureau issued 1,590 policies insuring ships and cargoes of a value of $145,831,602, for which the Government received in premiums $3,000,926.83, with a known loss to date of only $771,329.57, reduced through salvage AUDITOR FOR THE TREASURY DEPARTMENT The Auditor for the Treasury Depart- enue, Treasurer and assistant treasurers, ment receives and settles all accounts of mints and assay offices, Bureau of Enthe Department of the Treasury, includ- graving and Printing, Coast Guard, PubIng all accounts relating to the customs lie Health Service, Farm Loan Board, service, the public debt, internal rev- public buildings and Secret Service. Department of the Navy, including all Academy. AUDITOR FOR THE STATE AND OTHER DEPARTMENTS The Auditor for the State and Other ing governmental establishments : GovDepartments receives and settles the ac- ernment Printing Office ; Interstate Corncounts of the White House ; the two merce Commission ; Smithsonian InstituHouses of Congress ; the Supreme Court ; tion and National Museum ; District of the Departments of State, including the Columbia ; Civil Service Commission ; expenses of the Diplomatic and Consular the Federal Reserve Board ; the Federal Service ; Justice, covering expenses of Trade Commission ; and all boards, cornUnited States courts ; Agriculture, in- missions and establishments of the Govcluding its field service ; Commerce ; ernment not under the administration Labor ; also the accounts of the follow- of any executive department. The Auditor for the Post Office De- upon the Treasury issued in liquidation partment receives and examines all ac- of indebtedness ; superintends the colcounts of the office of the Postmaster lecting of debts due the United States General and of all bureaus and offices for the service of the Post Office Departunder his direction ; all postal and ment and all penalties imposed ; directs money order accounts of postmasters suits and all legal proceedings in civil and foreign administrations ; all ac- actions ; and takes all legal measures counts relating to the transportation of to enforce the payment of money due mails, and to all other business within the United States for the service of the the jurisdiction of the Post Office De- Post Office Department, and for this partment; and certifies the balances purpose has direct official relations with arising thereon to the Postmaster Gen- the Solicitor of the Treasury, Departeral for accounts of the postal revenue ment of Justice. He receives and acand expenditures therefrom, and to the cepts, with the written consent of the Secretary of the Treasury for other ac- Postmaster General, offers of comprocounts. He also receives and examines raise under sections 295 and 409, Revised reports and accounts of postmasters Statutes. He is required to submit to operating postal savings banks, and ac- the Secretary of the Treasury quarterly counts for expenditures from the appro- statements of postal receipts and expriation for continuing the establish- penditures, and to report to the Postment, maintenance, and extension of the master General the financial condition postal savings depositories. He registers, of the Post Office Department at the charges and countersigns the warrants close of each fiscal year. of the War Department, and performs such duties as are required of him by law or may be enjoined upon him by the President concerning the military service. He is charged by law with the supervision of all estimates of appropriations for the expenses of the department, including the military establishment ; of all purchases of Army supplies; of all expenditures for the support, transportation, and maintenance of the Army, and of such expenditures of a civil nature as may be placed by Congress under his direction. He also has supervision of the United States Military Academy at West Point and of military education in the Army, of the Board of Ordnance and Fortification, of the various battlefield commissions, and of the publication of Official Records of the War of the Rebellion. He has charge of all matters relating to national defense and seacoast fortifications, Army ordnance, river and harbor improvements, the prevention of obstruction to navigation, and the establishment of harbor lines ; and all plans and locations of bridges authorized by navigable waters of the United States require his approval. He also has charge of the establishment or abandonment of military posts, and of all matters relating to leases, revocable licenses, and all other privileges upon lands under the control of the War Department. To the Assistant Secretary of War is assigned the general direction and supervision of all matters relating to rivers and harbors; bridges over navigable waters of the United States ; leases, revocable licenses, and all other privileges upon lands under the control of the War Department ; inspections relating to the military establishment; recruiting service, discharges, commutation of rations, courts-martial, and other questions relating to enlisted men, including clemency cases and matters relating to prisoners at military prisons and penitentiaries. He also has charge of routine matters relating to the militia ; the promotion of rifle practice ; the supervision of miscellaneous claims and accounts ; matters relating to national cemeteries, boards of survey, open-market purchases, and medals of honor. The Assistant Secretary of War is also vested with authority to decide all cases which do not involve questions of policy, the establishment or reversal of precedents, or matters of special or extraordinary importance which may be assigned to him. ASSISTANT AND CHIEF CLERK The Assistant and Chief Clerk of the War Department is the head of the Office of the Secretary of War, and as such has charge of the records and files, and supervision of the receipt, distribution, and transmission of the official mail and correspondence of that office, and is charged with the administrative action required by law to be taken in connection with the settlement of disbursing officers' accounts that do not relate to the different staff corps of the Army. He has general supervision of matters relating to civilian employees in and under the War Department; printing and appropriations for contingent expanses, stationery, rent of buildings; and the department's telegraph and telephone service; and performs such other duties as may be required by the Secretary of War. THE GENERAL STAFF CORPS, U. S. ARMY The duties of the General Staff Corps, as stated in the organic act of Congress establishing it, are: OFFICE OF THE CHIEF OF STAFF The Chief of Staff is the military advisor of the Secretary of War. The Office of the Chief of Staff, for the purpose of carrying into effect the supervising, co-ordinating and informing powers conferred upon him by law, constitutes a supervising military bureau of the War Department. The Chief of Staff issues, through the Adjutant General of the Army, all orders and instructions of the Secretary of War affecting the Regular Army and the National Guard. The collation and discussion of all obtainable data relating to strategical, tactical and logistic features of military operations at home and abroad ; the formulation of complete working plans for passing quickly from a state of peace to a state of war, including the mobilization of all the available military forces of the United States; also the preparation and keeping up to date of detailed plans of defensive and offensive operations against each country with which the United States might become involved in war. The collection, classification and distribution of military information concerning (a) the strength, organization, personnel, armament and equipment of our own and foreign armies; (6) natural and artificial routes of communication (rivers, canals, roads and railroads) ; (c) the manufacture of arms, ammunition and other war materials; (d) supplies of food, horses, mules, pack and draft animals; (e) road conduct of correspondence with them ; inspection of their accounts and recommendations as to their detail and relief ; the exchange of military information with foreign war offices through their representatives in Washington ; the preparation of instructions for the guidance of officers of the Army serving or traveling abroad or acting as military attaches or observers, and the collation of information contained in their reports. The collation, preservation, arrangement, filing and indexing of maps, sketches and plans, American and foreign ; and the general supervision over the compilation of a progressive military map of the United States and its possessions. our own and foreign countries. The preparation, from official records, of analytical and critical histories of important campaigns for distribution to the Army. The study of the needs of the military service, and recommending changes therein; consideration of matters pertaining to armament, equipment and clothing ; location, design and construction of posts. tary preparedness, when directed by higher authority, for submission to Congress, and such other schemes of legislation for the improvement of the military service as may be directed. The maintenance at the War College of a military library for the use of the War Department and the Army at large. The conduct of a photographic laboratory for the reproduction of maps, sketches, photographs and illustrations, lantern slides and such other photographic work as may be required for the War Department and the Army at large. The idea of a War College for the United States Army was first suggested by the Honorable Elihu Root, then Secretary of War, in his annual report for 1899. In the words of its founder, its purpose is "not to promote war, but to preserve peace by intelligent and adequate preparation to repel invasion. It is a growth and not a new departure. Only an institution permanent, but always changing The functions thus described are really those of a General Staff and it is worthy of note that the Army War College as first established by War Department order in 1901 performed the duties of such a body until the General Staff was actually created by Act of Congress in 1903. WAK COLLEGE, WASHINGTON, D. 0. In its individual elements, in which, by conference and discussion, a consensus of matured opinion can be reached, can sumed its true function of training perpetuate the result of individual effort, selected officers for staff duty and secure continuity of military policy, and higher command in war, the controlcommand for its authorized conclusive Hn<r irtaa Vuin<r fViof ^o^v. i -K 11 expressions of military judgment, upon llnS ldea bem£ that each class sha11 military questions, the respect and ef- be a useful adjunct to the General problems affecting our country. In order to accomplish this result, the year's work is made to include studies in the tactical and strategical handling of large bodies of troops, in the general control of the auxiliary services, and in offensive and defensive questions of military, as dependent upon national, policy. The course opens with map problems and map maneuvers of a practical nature, representing actual phases in military operations that might have to be undertaken by our forces in time of war. These studies are confirmed on the ground, whenever practicable, by terrain, tactical and staff rides. These problems are only sufficient to insure that ideas shall be uniform and that operations shall be conducted in accordance with an accepted doctrine of war. The remainder of the course includes a series of original investigations, studies of war plans, contributions to military monographs, studies in military geography, in methods of obtaining military information, and in military historical research. The final result is that each class contributes something of permanent value for future reference. This is possible only because the officers detailed to take the course are men of experience, preferably graduates of the Staff College at Fort Leavenworth, and well versed in the theory of their profession. The President of the Army War College is a general officer detailed to the General Staff as assistant to the Chief of Staff, and the faculty is selected from the graduates of the Army War College. At first the sessions of the Army War College were held in a private residence rented for the purpose in Washington and this continued until 1907 when the present magnificent building on the site of the old Washington Barracks was first occupied. It provides quarters not only for the War College but also for the bulk of the General Staff on duty in Wasnington. The building, which cost about $700,000, is of modern construction and material but is purely classic in design. It is massive, well proportioned and impressive. In size the building is 300 feet long and 125 feet deep. The materials used in the construction of the exterior are red Pompeian pressed brick, laid in Flemish bond, with ornamentation of limestone and roof of dark slate. CONFERENCE ROOM, WAR COLLEGE In the center of the front facade is the main entrance pavilion, consisting of a pedimental gable with massive piers on either side and beautifully proportioned Ionic columns in the center. The design of this entrance pavilion is duplicated at either end of the building. The portions of the structure flanking the pavilion are in the pilaster style of treatment. Great dignity is lent to the exterior by the approaches. Low granite steps lead to a wide platform paved with red brick laid in ornamental patterns. The building is one of the most artistic edifices in the country, and is considered to rival the Library of Congress in its technical perfection. The interior is perfectly adapted to its purposes. Passing under the entrance pavilion, the visitor arrives in the large rotunda, with its four columns supporting an octagonal dome. Immediately beyond this is the main lecture room for the War College, with a seating capacity of 250; to the right of the rotunda, in the center of the building, is the library, and to the left is the map room, both extending to the roof. On the long sides of the building are the various lecture and conference in the basement. The map room contains a magnificent collection of the military maps of all nations arranged for ready reference. The library contains more than 100,000 volumes, and its method of classi- ARMY OFFICERS rooms, record rooms, work rooms and offices. The galleries of the library and map room are set aside for map drafting and mounting. The photographic department, complete for every kind of work, the work- oped by the present Assistant Librarian, is considered to be the most remarkable and complete system of its kind for ready reference in this country. The Militia Bureau is vested with all administrative duties involving the organization, armament, instruction, equipment, discipline, training, inspection, and payment of the National Guard ; the conduct of camps of instruction of the National Guard, and the administrative duties connected with the preparation of the National Guard for participation in field exercises and maneuvers of the Regular Army ; the mobilization of the National Guard in time of peace ; and all matters not herein generically enumerated which do not under existing laws, regulations, orders, or practice come within the jurisdiction of the General Staff or any division or bureau of the War Department. OFFICE OF THE ADJUTANT GENERAL The Adjutant General is charged with the duty of recording, authenticating, and communicating to troops and individuals in the military service all orders, instructions, and regulations issued by the Secretary of War through the Chief of Staff, or otherwise; of preparing and distributing commissions ; of compiling and issuing the Army Register and the Army List and Directory ; of consolidating the general returns of the Army ; of arranging and preserving the reports of officers of the Army detailed to visit encampments of militia ; of compiling and maintaining a list showing the names of officers of the Army on detached service; of managing the recruiting service, and of conducting correspondence concerning the military service generally, including such as pertains to military training camps, rifle practice, the Officers' Reserve Corps, the Reserve Officers' Training Corps and the Enlisted Reserve Corps. He is also vested with the government and control, under the direction of the Secretary of War, of the United States Disciplinary Barracks and its branches, and all offenders sent thereto for confinement and detention ; and is charged with the duty of issuing and recording orders from the War Department remitting or mitigating sentences of general prisoners, or honorably restoring them to duty. The Adjutant General is vested by law with the charge, under the Secretary of War, "of the military and hospital records of the volunteer armies and the pension and other business of the War Department connected therewith ;" of publishing War Department regulations, manuals and miscellaneous documents pertaining to the military service and distributing to the Army such publica- tions, as well as those publications of a private nature as are useful in the military establishment; of publishing and distributing the Official Records of the Union and Confederate Armies ; of obtaining, compiling and keeping continually up to date all obtainable information as to the names, ages, addresses, occupations and qualifications for appointment as commissioned officers of the Army, in time of war or other emergency, of men of suitable ages who, by reason of having received military training in civilian educational institutions or elsewhere, may be regarded as qualified and available for appointment as such commissioned officers; and of issuing certificates of enlistment in the Enlisted Reserve Corps. He also has charge of the historical records and business of the permanent military establishment, and all pension, pay, bounty, and other business pertaining to or based upon the military or medical histories of former officers or enlisted men, including the consideration of applications for the Congressional Medal of Honor ; for the benefits of the act of Congress approved April 27, 1916, establishing the Army and Navy Medal of Honor Roll ; for certificates of military service, certificates of merit, and certificates authorizing the purchase of campaign badges, and for removal of charges of desertion and the issue of discharge certificates to such soldiers finally charged with desertion as are entitled to relief under the terms of existing law. The archives of the Adjutant General's office include all military records of the Revolutionary War in the possession of the General Government ; the records of all organizations, officers, and enlisted men that have been in the military service of the United unteer forces and the National Guard while in the active service of the United States ; the records of the movements and operations of troops ; the medical and hospital records of the Army ; all reports of physical examination of recruits and identi- fication records; the records of the Provost Marshal General's Bureau ; the records of the Bureau of Refugees, Freedmen, and Abandoned Lands ; and a considerable collection of Confederate records, including those pertaining to the legislative, executive, and judicial branches of the Confederate Government. The duty of the officers of the Inspector General's Department is to inspect the Army in all its details, and the scope of their inquiry includes every branch of military affairs. They exercise a comprehensive and general observation within the commands to which they are assigned over all that pertains to the efficiency of the Army, the condition and state of supplies of all kinds, of arms and equipments, of the expenditure of public property and money, and the condition of accounts of all disbursing officers of every branch of the service ; of the conduct, discipline and efficiency of officers and troops, and report with strict impartiality in regard to all irregularities that may be discovered, with a view to their being remedied. They also inspect the Soldiers' Home, the ten branches of the National Home for Disabled Volunteer Soldiers, the Army transports and National Guard ; and make investigations ordered by the Secretary of War or Department Commanders. The Judge Advocate General is directed by law to "receive, review, and cause to be recorded the proceedings of all courts-martial, courts of inquiry, and military commissions." He reports upon applications for clemency, parole, pardon, restoration to the colors, remission of citizenship rights, and re-enlistment of general prisoners and dishonorably discharged soldiers. He also furnishes the Secretary of War information and advice relating to lands under the control of the War Department, as well as reports and opinions upon legal questions arising under the laws, regulations, and customs pertaining to the Army, and upon miscellaneous questions arising under civil law ; examines and prepares legal papers relating to the construction of bridges, dams, or other work over or in navigable waters; drafts bonds and examines those given to the United States by disbursing officers, colleges, rifle clubs, and others ; examines, revises, and drafts charges against officers and soldiers; and drafts and examines deeds, contracts, licenses, and other legal papers relating to matters under the War Department Under the provisions of the Revised Statutes, Statutes at Large, current appropriation acts, and Army Regulations, the Quartermaster General is charged with the following duties: (a) Pay of officers and enlisted men of the Army, including Staff Corps and Staff Departments, Porto Rico Regiment of Infantry and Philippine Scouts ; additional pay for length of service and foreign service; pay of retired officers and retired enlisted men ; pay of Regular Army Reserve, Officers' Reserve Corps, Enlisted Men's Reserve; erlnarians; pay of nurses, hospital matrons, veterinarians of Cavalry and Field Artillery and Quartermaster Corps, contract surgeons and retired pay clerks ; expenses of courts martial, courts of inquiry, military commissions, and compensation of reporters and witnesses attending same ; travel allowance to .enlisted men on discharge ; value of clothing undrawn to enlisted men on discharge; interest on soldiers' deposits ; receiving and paying deposits of enlisted men ; gratuity pay. (&) Purchase of subsistence supplies for issue as rations to troops, civil employees, hospital matrons, and others entitled thereto; subsistence of masters, officers, crews, and employees of the Army Transport Service; hot coffee for troops traveling when supplied with cooked or travel rations ; meals for recruiting parties and applicants for enlistment while held under observation ; for sales to officers ; commutation of rations to the Cadets of the United States Military Academy; commutation in lieu of rations to enlisted men on furlough, enlisted men and male and female nurses when stationed at places where rations in kind can not be economically issued and when traveling on detached duty, enlisted men selected to contest for places or prizes in Army rifle competitions while traveling to and from place of contest, male and female nurses on leaves of absence, applicants for enlistment, and general prisoners while traveling under orders ; commutation in lieu of regular established ration for members of Nurse Corps (female) while on duty in hospitals, and for enlisted men, applicants for enlistment while held under observation, and general prisoners sick in hospitals ; prizes for enlisted men graduates of schools for bakers and cooks ; authorized issues of soap, candles, matches, and salt and vinegar for animals ; towels for offices ; authorized issues of toilet paper, toilet articles, barbers' and tailors' materials for use of general prisoners confined at military posts without pay or allowances, and applicants for enlistment while held under observation ; issue of toilet kits to recruits ; for other necessary expenses incident to the purchase, testing, care, preservation, issue, sale, and accounting for subsistence supplies; for purchase, issue, repair and maintenance of stoves, ranges, field ranges, field bakeries, and appliances for cooking and serving food to troops in garrison and in the field ; tableware, kitchen utensils, and mess furniture, stationery for the Army, including blank books, blank forms, and the necessary printing; purchase, issue, repair and maintenance of prescribed field equipment and supplies for garrison use ; purchase and issue of ice for use of troops, offices, and preservation of stores ; providing cold storage ; construction and maintenance of ice plants, laundries, post bakeries, and power plants for lighting, and for supply of water; purchase and issue of water bags, sterilizers and necessary chemicals for purifying water; purchase and issue of fuel for heating barracks, quarters and other public buildings and for cooking food ; fuel for operation of modern batteries, pumping and other power plants ; fuel for operation of transports and harbor vessels of the Army ; furnishing light, including mineral oil ; necessary furniture, text books, paper, and other equipment for post schools and libraries ; subscriptions for newspapers and periodicals for the enlisted men; forage for the animals of the Army, including bedding; purchase and issue of typewriters, adding machines, addressographs and other devices for use of the Army ; seeds and implements for raising forage at remount depots ; hire of all employees pertaining to the Quartermaster Corps; extra duty pay for members of disciplinary barracks guard, to enlisted men on duty as school teachers and. stewards and cooks at recruit depots ; purchase and issue of office furniture and office equipment; payment of rewards for apprehension of deserters and escaped military prisoners ; donations of $5 to dishonorably discharged prisoners; purchase and issue of blacksmiths' tools and materials, horse and mule shoes, horseshoe nails, wheelwrights' and other tools ; purchase and supply of flagstaffs, surveying instruments, refrigerators, wall lockers, trunk lockers, window shades, screen doors and window screens ; purchase and issue of animals for the Army ; equipment and maintenance of remount depots ; purchase, issue, and repair, maintenance and operation of wagons, motor vehicles, and other vehicles ; purchase, manufacture, and issue of harness and pack equipment ; purchase and manufacture of uniforms for the Army ; purchase and issue of other articles of clothing; purchase and manufacture of tentage and other articles of equipage ; purchase and issue of technical books ; transportation of troops and impedimenta ; transportation of civilian employees, of baggage of officers, troops and employees ; transportation of animals for the Army ; transportation of Army supplies; trans- wharfage, tolls, and ferriage ; construction, operation, and maintenance of harbor vessels for the Mobile Army and for the Coast Artillery, including mine planters and cable ships ; operation and maintenance of Army Transport Service on the Pacific and Atlantic Oceans and the Gulf of Mexico; charter of vessels for transport purposes ; lease of buildings for quarters, storehouses and offices; lease of grounds for camp sites; hire of lodgings for recruits ; care and protection of military reservations; care and maintenance of post cemeteries and national cemeteries ; care and improvement of grounds at military posts ; and attends to all matters connected with the military service which are not expressly assigned to some other bureau of the War Department. (c) Constructs and repairs quarters for officers, barracks for enlisted men, storehouses for storage of supplies, administration buildings, offices, power plants, roads, walks, wharves, water systems, viser of the War Department upon all medical and sanitary affairs of the Army. He has administrative control of the Medical Department ; the disbursement of its appropriations; the designation of the stations of medical officers, dental officers and veterinary surgeons, and the issuing of all orders and instructions relat- ing to their professional duties ; the recruitment, instruction and control of the Hospital Corps and of the Army Nurse Corps. He directs the selection, purchase and distribution of medical supplies. The Army Medical Museum, the library of the Surgeon General's Office, medical supply depots, and the general hospitals are under his direct control. The Chief of Engineers commands the Corps of Engineers, which is charged with reconnoitering and surveying for military purposes, including the laying out of camps, selection of sites, and formation of plans and estimates for military defenses, construction and repair of fortifications and their accessories, the installation of electric-power plants and electric-power cable connected with seacoast batteries, and furnishing the necessary electrical supplies connected therewith ; plan- ning and superintending of defensive or offensive works of troops in the field ; examination of routes of communications for supplies and for military movements ; construction and repair of military roads, railroads and bridges ; and military demolitions. In time of war, within the theater of operations, it has charge of the location, design, and construction of wharves, piers, landings, storehouses, hospitals, and other structures of general interest ; and of the construction, maintenance, and repair of roads, ferries, bridges, and incidental structures ; and of the construction, maintenance, and operation of railroads under military control, including the construction and operation of armored trains. The Corps of Engineers is also charged with the improvement of rivers and harbors ; with matters arising under the laws for the protection and preservation of navigable waters, including the establishment of harbor lines, anchorage grounds, and rules and regulations therefor; rules and regulations for canals owned, operated, or maintained by the United States, for any public navigable channel improved under authority of Congress, and for the navigation of streams on which the floating of loose timber and sack rafts is the principal method of navigation ; also with the issuance of permits for the construction, alteration, maintenance, and operation of bridges, the granting of permits for structures or work in navigable waters, and the removal of wrecks and other obstructions to navigation ; with questions pertaining to the supervision of the harbor of New York and adjacent waters to prevent obstructive and injurious deposits ; with surveying and charting the Great Lakes, the natural navigable waters of the New York State canals, Lake Champlain, the Lake of the Woods, and other boundary and connecting waters between said lake and Lake Superior ; with the preservation of Niagara Falls; with public buildings and grounds in the District of Columbia ; with the water supply of Washington, D. C. ; with the construction of monuments and memorials ; and The Chief of Ordnance commands the Ordnance Department, the duties of which consist in providing, preserving, distributing, and accounting for every description of artillery, small arms, and all the munitions of war which may be required for the fortresses of the country, the armies in the field, and for the whole body of the militia of the Union. In these duties are comprised that of determining the general principles of construction and of prescribing in detail the models and forms of all military weapons employed in war. - They comprise also the duty of prescribing the regulations for the proof and inspection of all these weapons, for maintaining uniformity and economy in their fabrication, for insuring their good quality, and for their preservation and distribution at all times. BOARD OF ORDNANCE AND FORTIFICATION The Board of Ordnance and Fortification was created in 1888 to assist in the development of war material, especially tLat pertaining to ordnance and fortification. The board has an appropriation from Congress for carrying out the development and test of inventions for which no special provision is otherwise made, and considers a very large number of inventions submitted by civilians, as well as persons in the military service, each year. A large amount of very important development work has been carried on under the board and the board is glad to have submitted to it any inventions relating to military subjects. The Chief Signal Officer is charged with the duty of operating or supervising the operation of all military air craft and with the duty of training officers and men connected therewith; with the supervision of all military signal duties, and of books, papers, and devices connected therewith, including telegraph, telephone, sary meteorological instruments for use on target ranges and other military uses; the construction, repair, and operation of military telegraph lines and cables, and the duty of collecting and transmitting information for the Army by telegraph or otherwise, and all other duties usually pertaining to military sig- The Office of Public Buildings and Grounds, Washington, D. C., is the successor of the Commissioners of Public Buildings and Grounds, established in 1792 under the direction of President Washington, and is now a bureau of the War Department. The United States Army Engineer Officer in Charge is Military Aide to the President. He administers the public park system of the District of Columbia for the Chief of Engineers, United States Army, under whose jurisdiction and control it has been placed by law ; this park system comprises over 400 parcels of Federal property, amounting in all to over 1100 acres, and includes the Mall System as proposed by L'Enfant and elaborated by the Park Commission of 1901. He is in charge of the preservation, care and safety of all the buildings occupied by the War Department, of mac and of the monument at the birthplace of Washington. As Executive and Disbursing Officer of the Grant Memorial Commission, of the Lincoln Memorial Commission, of the Arlington Memorial Amphitheater Commission and of the Francis Scott Key Monument Commis- erected at Fort McHenry, Baltimore, Md.), he supervises and controls the erection of those memorials. As Executive and Disbursing Officer of the Rock Creek and Potomac Parkway Commission he has the development of that project under his charge. He is a member and disbursing officer of the commission to prepare plans and estimates for an armory for the National Guard of the District of Columbia, and he is Executive and Disbursing Officer of the Arlington Memorial Bridge Commission. War the War Department was confronted with varied and complex problems in the administration of the civil affairs of the territory occupied by the military forces of the United States. There were no precedents to which the officers charged with the administration of the affairs of this territory could turn for guidance, and the difficul- ties of these officers were further complicated owing to the lack of any administrative machinery for handling these problems. Notwithstanding the frequency in the past with which the War Department had been called on to conduct military governments and civil governments during military occupation, there had existed in the department no bureau or division to which in a particular manner was committed this work of supervision. The then Secretary of War, recognizing the urgent need of such a bureau or division, organized, in December, 1898, the Division of Insular Affairs. The rapid growth of the division thus organized led to its being given a legal existence July 1, 1902, and since that date has been known as the Bureau of Insular Affairs. To the Bureau of Insular Affairs, under the immediate direction of the Secretary of War, is assigned all matters pertaining to civil government in the island possessions of the United States subject to the jurisdiction of the War Department, the Philippine Islands and Porto Rico being the only ones so subject at the present time. The bureau is also the repository of the civil records of the government of occupation of Cuba, and had assigned to it matters pertaining to the provisional government of Cuba. It makes a and expenditures of the Philippine and Porto Rican governments; attends to the purchase and shipment of supplies for these governments ; has charge of appointments of persons in the United States to the civil service of the Philippines and Porto Rico, including arrangements for transportation. It gathers statistics of insular imports and exports, shipping and immigration, and issues periodical summaries of the same. In addition the bureau has, subject to the direction of the Secretary of State, supervision and control of the Dominican Receivership for the collection of customs revenues and payment of the interest and principal of the adjusted bonded indebtedness of the Dominican Republic. It exercises for the receivership practically the same functions as it does for the insular possessions, particularly with respect to the custody of records, the preparation and dissemination of statistics and other information, the purchase of supplies and the appointment of employees. BOARD OF ENGINEERS FOR RIVERS AND HARBORS The Board of Engineers for Rivers and Harbors is a permanent body, created by the River and Harbor Act of June 13th, 1902. To it are referred all reports upon examinations and surveys provided for by Congress, and all projects or changes in projects for works of river and harbor improvement upon which report is desired by the Chief of Engineers, United States Army. It is further the duty of the Board, upon request by the Committee on Commerce of the Senate, examine and report through the Chief of Engineers upon any examinations, surveys, or projects for the improvement of rivers and harbors. In its investigations the board gives consideration to all engineering, commercial, navigation and economic questions involved in determining the advisability of undertaking such improvements at the expense of the United States. 1. It is the duty of the Chief of Coast Artillery to keep the Chief of Staff advised and informed with respect to the business under his charge, including the efficiency of the personnel and material of the coast artillery, and he shall, as circumstances require, make such recommendations in reference there- promote efficiency. 2. He shall from time to time, and as frequently as conditions require, confer directly with the chiefs of bureaus of the War Department and advise them of all matters relating to coast artillery material or personnel that pertain to their re- spective branches of the service, which the experience and observation of the coast artillery arm of the service show to be of practical importance. In like manner he may correspond directly with the commandant of the Coast Artillery School, and with the president of the Coast Artillery Board, on coast artillery questions of a purely technical character which do not involve matters of command, discipline, or administration, and do not relate to the status or interests of individuals. 3. He shall make recommendations as to the instruction of coast artillery officers and men, and as to examinations for appointment and transfer of officers to the coast artillery arm and for promotion therein, and shall recommend such examinations and such courses aud methods of instruction in the Coast Artillery School and elsewhere as he shall deem requisite to secure a thoroughly trained and educated force; to this end he is authorized to issue directly to coast artillery officers bulletins and circulars of information on current coast artillery matters of a purely technical character which do not involve matters of command, discipline, or administration, and do not relate to the status or interests of individuals. 4. He is charged with the recommending of officers of coast artillery for special duty and assignment to coast artillery organizations and stations. ed States in matters involving legal questions; he gives his advice and opinion, when they are required by the President or by the heads of the other executive departments, on questions of law arising in the administration of their respective departments; he appears in the Supreme Court of the United States in cases of especial gravity and importance ; he exercises a general superintendence and direction over United States attorneys and marshals in all judicial districts in the • States and Territories ; and he provides special counsel for the United States whenever required by any department of the Government. SOLICITOR GENERAL The Solicitor General assists the Attorney General in the performance of his general duties, and, by special provision of law, in case of a vacancy in the office of the Attorney General, or of his absence or disability, exercises all those duties. Under the direction of the Attorney General, he has general charge of the business of the Government in the Supreme Court of the United States, and is assisted in the conduct and argument of cases therein by the Assistant Attorneys General. He also, with the approval of the Attorney General, prepares opinions ren- dered to the President and the heads of the executive departments, and confers with and directs the law officers of the Government throughout the country in the performance of their duties. When the Attorney General so directs, any case in which the United States is interested, in any court of the United States, may be conducted and argued by the Solicitor General; and he may be sent by the Attorney General to attend to the interests of the United States in any State court, or elsewhere. Performs such other duties as may be required. The Assistant to the Attorney General has special charge of all suits and other matters arising under the Federal anti-trust and inter- state-commerce laws, and performs such other duties as may be required of him, from time to time, by the Attorney General. ASSISTANT ATTORNEYS GENERAL The several Assistant Attorneys General assist the Attorney General in the performance of his duties. They assist in the argument of cases in the Supreme Court and in the preparation of legal opinions. Five Assistant Attorneys General are located in the main department building at 1435 K Street, and, in addition to their general duties, particular subjects are assigned to them by the Attorney General for the transaction of business arising thereunder with United States attorneys, other departments, and private parties in interest. Jackson Place. The Assistant Attorney General in charge of the interests of the Government in all matters of reappraisement and classification of imported goods in litigation before the several boards of United States General Appraisers and the Court of Customs Appeals, is located at 641 Washington Street, New York. The Assistant Attorneys General and the solicitors for the several executive departments exercise their functions under the supervision and control of the Attorney General. They are the Solicitor for the Department of the Interior, the Solicitor for the Department of State, the Solicitor of the Treasury, the Solicitor of Internal Revenue, the Solicitor of the Department of Commerce, and the Solicitor of the Department of Labor. PUBLIC LANDS DIVISION To it are assigned all suits and proceedings concerning the enforcement of the public-land law, includ- The chief clerk, under the direction of the Attorney General, has general supervision of the clerks and employees ; the consideration of applications for leave of absence ; the direction of the force of laborers, charwomen and watchmen ; superintends all buildings occupied by the department in Washington ; has charge of the horses, wagons and carriages employed ; has supervision of the Division of Mails and Files; the purchase and distribution of supplies for the department and the United States courts ; the expenditure of the appropriations for contingent expenses and rents ; the consideration of requisitions upon the Public Printer for printing and binding ; and supervision of the preparation of the annual report and the estimates of the department. DISBURSING CLERK The disbursing clerk disburses from about forty appropriations, under the direction of the Attorney General, including the salaries of the Justices of the Supreme Court of the United States and the judges of the other United States courts located in the District of Columbia ; the salaries of the officials of the department proper, as well as the salaries and expenses of certain employees stationed in the field ; the contingent expenses of the department : supplies for United States courts ; and other special and miscellaneous appropriations. He is also authorized and directed by law to withhold and account for the income tax as it may apply to Federal employees. The superintendent of prisons has charge, under the direction of the Attorney General, of all matters relating to United States prisons and prisoners, including the support of such prisoners In both State and Federal penitentiaries, In reform schools and in county jails. He has supervision over the construction work in progress at United States penal institutions. CHIEF OF THE DIVISION OF ACCOUNTS The Chief of the Division of Accounts court accommodations ; and the advancehas charge of the examination or audit ment of funds to United States marof all accounts payable from appropria- shals ; also matters relating to the aptions for expenses of the Department of pointment of office and field deputy marJustice and the courts of the United shals are in charge of the chief of this States. Accounts of United States mar- division. shals, attorneys, clerks, and commission- Statistical information published in ers are examined, recorded, and trans- the annual report of the Attorney Genmitted to the auditor ; while other ac- eral showing the business transacted in counts are recorded, audited, and trans- the courts of the United States, bankmitted to the disbursing clerk for pay- ruptcy statistics, and the various rement. under recent legislation. ports required by law pertaining to exAuthorization of court expenses, in- penditures under appropriations for the eluding items for office expenses and courts and the various divisions of clerical assistants for clerks of United the department are also compiled in States courts ; the approval of leases of this division. The Chief of the Division of Invest!- compensation or expenses are paid from gation has general supervision of the the appropriation "Detection and proseexamination of the offices and records cution of crimes," and who are employed of the Federal court officials throughout for the purpose of collecting evidence the United States, and directs the work or of making investigations or examinaof all the examiners, special agents, and tions of any kind for this department accountants of the department, whose or the officers thereof. executive head of the Federal Postal Service. He appoints all officers and employees of the Post Office Department except the four Assistant Postmasters General and the purchasing agent, who are Presidential appointees. With the exception of postmasters of the first, second and third classes, who are likewise Presidential appointees, he appoints all postmasters and all other officers and employees of the service at large. Subject to the approval of the President, he makes postal treaties with foreign Governments. He promulgates all rules and regulations ; superintends generally the business of the department, and executes all laws relative to the postal service. Much information is contained in his annual report. The chief clerk of the Post Office Department is charged with the general superintendence and assignment of the clerical and subclerical forces of the department and the consideration of applications for leave of absence for such employees ; the supervision of the preparation of estimates of appropriations for the departmental and postal service : of advertising ; the supervision of requisitions upon the Treasury and the expenditure of the appropriations for the departmental service ; the keeping of the Journals and order books ; the furnishing of stationery supplies for the departmental service ; the consideration and signing of requisitions upon the Public Printer for the printing and bindiMg required in the Postal Service and the department, and receiving, and inspecting on receipt, of blanks required in the Post Office Department ; the preparation of contracts and general superintendence of the publication and distribution of the Official Postal Guide; the fixing of rates, subject to the approval of the Postmaster General, for the transmission of Government telegrams ; the miscellaneous business correspondence of the Postmaster General's Office, and miscellaneous correspondence of the department not assigned to other offices : the care of the department and other buildings used in connection therewith, and of all furniture and public property therein ; and the performance of such other duties as may be required by the Postmaster General. The solicitor is charged with the duty of giving opinions to the Postmaster General and the heads of the several offices of the department upon questions of law arising upon the construction of the postal laws and regulations, or otherwise, in the course of business in the Postal Service ; with the consideration and submission (with advice) to the Postmaster General of all claims of postmasters for losses by fire, burglary, or other unavoidable casualty, and of all certifications by the Auditor for the Post Office Department of cases of proposed compromise of liabilities to the United States, and of the remission of fines, penalties, and forfeitures under the statutes ; with the giving of advice when desired in the preparation of correspondence with the Department of Justice and other departments, including the Court of Claims, involving questions of law or relating to prosecutions or suits affecting or arising out of the Postal Service, and with assisting when desired in the prosecution or defense of such cases, and the maintenance of suitable records of opinions rendered affecting the Post Office Department and the Postal Service ; and with the consideration of applications for pardon for crimes committed against the postal laws which may be referred to the department ; with the preparation and submission (with advice) to the Postmaster General of all appeals to him. from the heads of the offices of the department depending upon questions of law ; with the determining of questions as to the delivery of mail the ownership of which is in dispute ; with the hearing and consideration of cases relating to lotteries and the misuse of the mails in furtherance of schemes to defraud the public; with the consideration of all questions relating to the mailability of alleged indecent, obscene, scurrilous, or defamatory matter ; with determining the legal acceptability of securities offered by banks to secure postal savings deposits ; with the examining and, when necessary, drafting of all contracts of the department ; and with such other like duties as may from time to time be required of him by the Postmaster General. PURCHASING AGENT The purchasing agent supervises the purchase of all supplies both for the Post Office Department proper and for all branches of the Postal Service. He reviews all requisitions and authorizations for supplies and, if proper, honors the same. He passes upon the sufficiency and propriety of all specifica- tions for proposals for supplies ; prepares the advertisements and forms for proposals necessary to the making of contracts for supplies ; reviews the reports of the committees on awards and recommends to the Postmaster General such action as in his judgment should be taken thereon. CHIEF INSPECTOR The chief inspector supervises the work of post office inspectors and of the division of post office inspectors. To him is charged the preparation and issue of all cases for investigation, all matters relating to depredations upon the mails and losses therein, the custody of money and property collected or received by inspectors, and the restoration thereof to the proper parties or owners, and the consideration and adjustment of accounts of inspectors for salary and expenses. To his office are referred all complaints of losses or irregularities In the mails and all reported violations of the postal laws. duties specified: Post Office Service. — The organization of post offices, salaries of postmasters, the appointment and salaries of assistant postmasters, supervisory officers, clerks, aud city letter carriers, authorization of new or changes in existing service on pneumatic tube routes, and Government-owned automobile routes, establishment of mail messenger and regulation, screen, or other wagon service, the performance of service by contractors on such, routes and complaints concerning the same, Government-owned automobile service, the establishment, maintenance and extension of city delivery-andcollection service, and all matters concerning special delivery service. Allowances for rent, light, fuel, clerk hire, labor incident to cleaning post offices, telephone rental, water rental, laundering, towel service, and miscellaneous service items. Postmasters' Appointments.- — The appointment of a postmaster, to postmasters' bonds and commissions, bonds of all employees in past offices except rural carriers and village delivery carriers, leave of absence of postmasters, and the establishment, discontinuance, or change of site, of a fourth-class post office. Dead Letters. — The treatment of all unmailable and undelivered mail matter which is sent to it for disposition; the examination and forwarding or return of all letters which have failed of delivery ; the inspection and return to the country of origin of undelivered foreign matter; recording and restoration to owners of letters and parcels which' contain valuable inclosures ; care and disposition of all money, negotiable paper, and other valuable articles found in undelivered matter and SECOND ASSISTANT POSTMASTER GENERAL The Second Assistant Postmaster General has charge of the authorization of new or changes in existing steamboat, aviation and Alaska star route services. Railicay Adjustments. — Has charge of the preparation of cases authorizing the transportation of mails by railroads; the establishment of railway postal car service and changes in existing service; prepares orders and instructions for the weighing of the mails on railroads; receives and tabulates the returns and computes basis of pay therefrom ; prepares cases for adjustment of allowances to railroads for carrying the mails, and for postal cars; authorizes expenditures and credits for the weighing of the mails, and transportation by freight or express of postal cards, stamped envelopes, periodical mail matter and mail equipment; and prepares all correspondence relative to these matters. Foreign Mails. — Is charged with the duty of arranging all details connected with the transportation of foreign mails; the preparation of postal conventions (except those relative to the money-order system) and the regulations for their execution, as well as the consideration of the questions arising under them and with the preparation of all correspondence relative thereto. Also has supervision of the ocean mail service, including the adjustment of accounts with steamship companies for the transportation of mails to foreign countries. Railway Mail Service. — Is charged with the supervision of the Railway Mail Service and railway postal clerks ; prepares cases for the appointment, removal, promotion, and reduction of said clerks ; conducts correspondence and issues orders relative to the moving of the mails on railroad trains ; has charge of the dispatch and distribution of mail matter in railway postal cars and post offices ; conducts the weighing of mails; and attends to all correspondence relative to these matters. Finance. — The financial operations, including the collection and deposit of postal revenues ; the distribution of postal funds among the several depositaries so as to equalize, as far as possible, receipts and expenditures in the same section ; the payment by warrant of all accounts settled by the auditor; the receipt and disposition of all moneys coming directly to the department; and the keeping of books of account showing the fiscal operations of the .postal and money-order services and the regulation of box rents and key deposits. Stamps. — The supervision of the manufacture and issuance to postmasters of postage stamps, stamp books, stamped envelopes, newspaper wrappers, postal cards, and postal saving stamps and cards by the various contractors ; and the keeping of the accounts and records of these transactions. The receipt and disposition of damaged and unsalable stamped paper returned by postmasters for redemption and credit. Money Orders. — The supervision and management of the money-order service, both domestic and international; the preparation of conventions for the exchange of money orders with foreign countries. surance, and collect-on-delivery services ; the establishment and control of all registry dispatches and exchanges ; the instruction of postmasters and the furnishing of information in relation to these matters ; and the consideration of all claims for indemnity for lost registered, insured, and C. O. D. mail. Classification. — The general control of all business relating to the classification of domestic mail matter and the rates of postage thereon, including the determination of the admissibility of publications to the second class of mail matter, their right to continue in that class, and the instruction of postmasters rela- tive thereto ; also the use of penalty envelopes, the franking privilege, and the limit of weight and size of mail matter. Postal Savings. — The conduct and management of the administrative office of the postal savings system at Washington ; the selection and designation of post offices as postal savings depository offices and the supervision of the business transacted at such offices ; the management and investment of postal savings funds as the agent of the board of trustees; and the administrative examination of accounts of postmasters and other fiscal agents of the system. sion of Rural Mails, with horsedrawn and motor vehicle service, and the star route service, the Division of Equipment and Supplies, and Village Delivery. All requests for rural service, star route service or extensions of service, the appointment and discipline of rural carriers, and the preparation of all advertisements inviting proposals for star routes, and making awards and contracts, making rural delivery maps and distributing parcel post maps and guides, and all supplies which postmasters need in the conduct of postal business, including office appliances of every description, and all correspondence relating thereto, belong to the duties of this office. ing of the mail bag repair shop and the lock shop, are also under the direction of the Fourth Assistant. All repairs, and the manufacture of new sacks and pouches when necessity requires, the manufacture of all locks and repair of same, and all mechanical devices used in the Railway Mail Service and post offices, which can be furnished from the lock shop, as well as new mechanical designs and improvements for the service, are included. The experimental and research work connected with such manufacturing enterprises, made necessary to meet new and changing conditions, determining the needs of the service as to style and character of equipment, and assure economy in expenditures, is directly under the personal supervision and control of the head of this bureau. is Commander in Chief, may assign him, and has the general superintendence of construction, manning, armament, equipment, and employment of vessels of war. The chief clerk has general charge of the records and correspondence of the Secretary's office, and per- gress of March 3, 1915. That act provided that the Chief of Naval Operations should be selected from an officer of the line of the Navy not below the rank of captain and that while holding this position he should have the rank, title and emoluments of a rear admiral. The act of August 29, 1916, provides that while so serving the Chief of Naval Operations shall have the rank and title of admiral, to take rank next after the admiral of the Navy and shall receive the pay of $10,000 per annum and no allowances. He is appointed for a period of four years. The Chief of Naval Operations is charged, under the direction of the Secretary of the Navy, with the operations of the fleet and with the preparation and readiness of plans for its use in war. This includes the direction of the Naval War College, the Office of Naval Intelligence, inspections, gunnery exercises and engineering performances, the operation of the radio service and of other systems of communication, the operations of the aeronautic service, of mines and mining, of the naval districts, Naval Militia, and of the Coast Guard when operating with the Navy ; the direction of all strategic and tactical matters, organization, maneuvers, target practice, drills and exercises, and of the training of the fleet for war; and the preparation, revision and enforcement of all tactics, drill books, signal codes and cipher codes. The orders issued by the Chief of Naval Operations in the performance of his duties are considered as emanating from the Secretary of the Navy and have full force and effect as such. COMMUNICATIONS OFFICE The Communications Office under the direction of the Chief of Naval Operations handles all the dispatch work of the Navy Department (radio, telegraph, cable, and telephone). A commissioned officer is on watch in the Communications Office at all times, night and day, and is responsible for the routing, coding, and decoding of all dispatches. He is responsible for the proper delivery of all received official dispatches. The Assistant Communications Officer on watch keeps himself informed of the general and special situations in order that he may thoroughly understand the bearing of dispatches received outside of departmental hours, and he is responsible that dispatches of importance requiring immediate action are communicated as soon as possible to the proper officer. OFFICE OF NAVAL INTELLIGENCE The Office of Naval Intelligence is charged with the collection and dissemination of such technical information at home and abroad as will be useful to the Chief of Naval Operations and to the various bureaus of the Navy Department in the formulation of plans for war and in the development of personnel and materiel. OFFICE OF GUNNERY EXERCISES AND ENGINEERING PERFORMANCES The Office of Gunnery Exercises and Engineering performances is charged with the duties, under the Chief of Naval Operations, of formulating the rules for all forms of gunnery exercises and steaming performances ; computing, compiling, and publishing in confidential form the results and records of these competitions; the award of prizes, trophies, and commendatory letters in connection therewith, these competitions being the means fo the end; i. e., battle efficiency. The Office of Director of Naval Communications is established under the Chief of Naval Operations. The Director of Naval Communications is charged with matters pertaining to the operation of naval radio stations ashore, and in addition is charged with the duties in connection with and is responsible for the efficient handling of all telegraph, telephone and cable and generally all dispatch work between the Navy Department and the fleet, and throughout the naval service outside the fleet. In his administration of the foregoing he has general charge of the operation, organization, and administration of the Communication Service. He co-operates with officials designated by the Secretary of Commerce in reference to location of proposed commercial stations, the licensing of operators, the control of the operation of commercial stations under the law, and the assignment of wave lengths for use by commercial stations which will comply with the law and thereby prevent possible interference with the organization and opera- Since the passage of the Naval Militia Act of February 16, 1914, the activities of the Naval Militia insofar as they concern the Federal Government have come under the Navy Department. All duties in connection with the instruction and training of the Naval Militia and of vessels loaned for their use are under the control of the Chief of Naval Operations. This part of the activities of the office of the Chief of Operations is directly in the hands of the Division of Naval Militia Affairs. This division is, in effect, a complete Navy Department for the Naval Militia insofar as the Federal Government is concerned. The Naval Militia Act of February 16, 1914, provided that the Secretary of the Navy is authorized to so organize, arm, uniform, equip, and train the Naval Militia that it may be eligible to be called forth by the President of the United States to serve the United States in the event of war, actual or threatened, with any foreign nation. In consequence of this act the Secretary of the Navy has defined the units, the number and rank of officers, and the number and rates of petty officers and enlisted men of all Naval Militia organizations. The Division of Naval Militia Affairs has laid down a standard of professional and physical examinations for all grades and ranks in the Naval Militia in order BUREAU OF The duties of the Bureau of Navigation comprise the issue, record and enforcement of the orders of the secretary to the individual officers of the Navy ; the training and education of line officers and of enlisted men (except of the Hospital Corps) at schools and stations and in vessels maintained for that purpose; the upkeep and operation of the Naval Academy, of technical schools for line officers, of the apprenticeseamen establishments, of schools for the technical education of en- that such officers and men may be mustered into service without further appointment, enlistment or examination. The division also has control of regulations and contracts under which vessels of the Navy are loaned to the Naval Militia for their training and instruction. Officers are appointed to make annual inspections of Naval Militia organization. Rules and regulations covering the details of training have also been laid down by the division to cover instruction for the Naval Militia given by inspector-instructors, officers of the regular Navy detailed for this specific duty. The division also conducts Cruises for instruction of the Naval Militia on vessels of the regular Navy, vessels loaned to the State, aeronautic encampments and Marine Corps encampments. All matters pertaining to the Naval Militia under existing laws and regulations come within the jurisdiction of the Division of Naval Militia Affairs. The records of officers and men, cruises and all like duties of the Naval Militia are kept in the D. N. M. A. In the event of the mustering into the Federal service of the Naval Militia for active duty the division from its records of officers and men would recommend the detail of such officers and men and their orders would be based on such recommendations. NAVIGATION listed men, and of the naval home at Philadelphia, Pa. ; the upkeep and the payment of the operating expenses of the Naval War College ; the enlistment, assignment to duty, and discharge of enlisted persons. (2) It has under its direction all rendezvous and receiving ships, and provides transportation for all enlisted persons under its cognizance. an annual Navy Register for publication, embodying therein data as to fleets, squadrons, and ships, which shall be furnished by the Chief of Naval Operations. To the end that it may be able to carry out the provisions of this paragraph, all communications to or from ships in commission relating to the personnel of such ships are forwarded through this bureau, whatever their origin may be. (5) It is charged with all matters pertaining to applications for appointments and commissions in the Navy, and with the preparation of such appointments and commissions for signature. (6) It is charged with the preparation, revision, and enforcement of all regulations governing uniform, and with the distribution of all orders and regulations of a general or circular character. (7) Questions of naval discipline, rewards, and punishments are submitted by this bureau for the action of the Secretary of the Navy. The records of all general courts-martial and courts of inquiry involving the personnel of the Navy before final action are referred to this bureau for comment as to disciplinary features. (8) It receives and brings to the attention of the Secretary of the Navy all applications from officers for duty or leave. er men. (10) It is charged with the enforcement of regulations and instructions regarding naval ceremonies and naval etiquette. (11) It shall be charged with the upkeep and operation of the Hydrographic Office, the Naval Observatory, Nautical Almanac, and Compass offices ; with all that relates to the supply of ships with navigational outfits, including instruments, and with the maintenance and repair of the same; with the collection of foreign surveys, and with the publication and supply of charts, sailing directions, and nautical works, and the dissemination of nautical, hydrographic, and meteorological information to the Navy -and mercantile marine. It shall also have charge of all ocean and lake surveys, and ships' and crews' libraries; it shall defray the expenses of pilotage of all ships in commission. (12) It shall be charged with the formation of the Naval Reserve and with all matters relating thereto. the United States east of the Rocky Mountains with the standard time at noon, seventy-fifth meridian time, each day, both by telegraph and radio, while the chronometer and time station at the Navy Yard, Mare Island, California, does the same for the country west of the Rockies. Through the Navy Radio Station the Observatory furnishes vessels naviirating the north Atlantic Ocean and the Gulf of Mexico the standard time twice each day, at noon and 10 P. M., and these radio time signals are becoming increasingly used, by persons having receiving wireless sets throughout the country, in preference to the telegraphic signals. Navigators, surveyors and astron- omers are kept supplied with the positions of the heavenly bodies in a form for practical use through the American Ephemeris and Nautical Almanac, and the American Nautical Almanac through the Nautical Almanac Office, which is a department of the Naval Observatory. In order to assist in furnishing data to keep the Almanac and Ephemeris up to the highest attainable standard of accuracy continuous fundamental observations of the heavenly bodies are kept up at the Observatory. The duties of the Bureau of Yards and Docks comprise all that relate to the design and construction of public works of the Navy, such as dry docks, marine railways, building ways, harbor works, quay walls, piers, wharves, slips, dredging, landings, floating and sta- astronomer wishes to find his astronomical position on the globe he does it by observations of the heavenly bodies, using the Nautical Almanac and a comparison of his local time with that of the Observatory. The Naval Observatory also supervises the supplying of the vessels of the Navy and the Naval Air Service with all the instruments used for navigating them, which are numerous and interesting. YARDS AND DOCKS vehicles, horses, teams, subsistence, and necessary operators and teamsters in the navy yards. It provides clerks for the office of the commandant, the captain of the yard, and public works officer. COMPARING DECK CLOCKS FOR WAR VESSELS tionary cranes, power plants, coaling plants, heating, lighting, telephone, water, sewer and railroad systems; roads, walks and grounds; bridges, radio towers, hospitals and all buildings for whatever purpose needed, under the Navy and Marine Corps. It has charge of all means of transportation, such as derricks, shears, locomotives, locomotive cranes, cars, motor trucks, and all cers of the Corps of Civil Engineers, United States Navy, whose major duties comprise the construction, repair and maintenance of the public works and utilities of the Navy. east coast, and at Mare Island and Puget Sound on the west coast. In addition a 1,000-foot dry dock is now under construction at the Naval Station, Pearl Harbor, Hawaii. This dock when completed is estimated to cost approximately $4,986,500. To provide an entrance channel from the sea to the site of the dock and the naval station, extensive dredging operations were necessary, over $3,000,000 having been expended for this purpose under a single contract. During the last ten years there have been expended under the cognizance of this bureau approximately $70,500,000. The bureau is justly proud of its record in connection with the construction and operation of the central power plants at the various navy yards, these central plants having been provided for by act of Congress in 1904, in order to avoid the great waste in connection with the operation of many separate plants at each yard. Fourteen such central power plants have been constructed and equipped with the most modern apparatus. To give an idea as to their magnitude it may be stated that these plants produced during the fiscal year 1915 a total of approximately 50,000,000 kilowatt hours of electric power, 6,000,000,000 cubic feet of compressed air, and 3,000,000,000 pounds of steam. The rapid increase in the use of fuel oil as a source of power for ships has led to the construction of extensive fuel oil storage plants, some seven plants having been completed, with many others contemplated. The present capacity of these plants is approximately 30,000,000 gallons of oil, which will probably be increased to 150,000,000 gallons. These plants are equipped with powerful pumps capable of delivering heavy oils from tanks to ships at the high rate of 1,000 gal- lons per minute. The tanks are equipped with automatically controlled fire systems, which provide in case of fire a blanket of inert gas in the form of foam over the surface of the oil. The bureau has had charge of the design and construction of radio towers and other public works connected with the development of the high power radio stations of the Navy. The location of these stations is shown on the Military -Naval Map. The first of these stations to be completed was that at Arlington, Virginia. Others have followed at Colon and Balboa on the Isthmus ; Chicago, Illinois ; Chelsea, Massachusetts ; Washington, D. C. ; Key West, Florida; New Orleans, Louisiana; Point Isabel, Texas ; Guantanamo, Cuba; Cordova, Alaska; Keyport, Washington; San Diego, California; Pearl Harbor, Hawaii ; Island of Guam; Cavite, P. I. The stations in Hawaii have been in telephonic communication by wireless with the radio station at Arlington, Virginia. This bureau has designed and constructed practically all of the important graving docks in the United States. Most of these docks have been built by and for the Navy. It has, by arrangements made between the Commonwealth of Massachusetts and the Navy Department, designed and is supervising the construction of the State Graving Docks in Boston. It will also give general supervision to the graving dock to be constructed by the Union Iron Engineers of the Navy has been connected with the construction of the Panama Canal as Commissioner and also Engineer of Terminal Construction. This bureau has been represented by one of its officers on the International Board of Consulting Engineers. pedo Station at Newport, R. I., besides all of the magazines and ammunition depots pertaining to the Navy. The duties of the Bureau of Ordnance comprise all that relates to the upkeep, repair and operation of the torpedo station, naval proving ground, and magazines on shore, to the manufacture of offensive and defensive arms and apparatus (including torpedoes and armor), all ammunition and war explosives. It requires for or manufactures all machinery, apparatus, equipment, material and supplies required by or for use with the above. It determines the interior dimensions of revolving turrets and their requirements as regards rotation. As the work proceeds it inspects the installation of the permanent fixtures of the armament and its accessories on board ship, and the method of stowing, handling, and transporting ammunition and torpedoes, all of which work must be performed to its satisfaction. It struction of armories and ammunition rooms on shipboard, and, in conjunction with the Bureau of Construction and Repair, determines upon their location and that of all ammunition hoists outside of turrets. It installs all parts of the armament and its accessories which are not permanently attached to any portion of the structure of the hull, excepting turret guns, turret mounts, and ammunition hoists, and such other mounts as require simultaneous structural work in connection with installation or removal. It confers with the Bureau of Construction and Repair respecting thearrangements for centering the turrets and the character of the roller paths and their supports. It has cognizance of all electrically operated ammunition hoists, rammers and gun-elevating gear which are in turrets; of electric training and elevating gear for gun mounts not in turrets ; of electrically operated air compressors for charging torpedoes ; and of all range finders and battle order and range transmitters and indicators. The head of this Bureau is the Chief Constructor, who is an officer of the Construction Corps of the Navy and is appointed by the President and confirmed by the Senate for a four-year term. By the authority of statute law orders issued by him in regard to the work of this bureau have the same force and effect as though issued by the Secretary of the Navy. The Chief Constructor is responsible for the general designs of all vessels of the Navy and for incorporating therein the military characteristics approved by the Secretary of the Navy and for making the necessary provision in the design and in the completed ship for the propelling machinery, ordnance and other items under the cognizance of other bureaus of the Navy Department. He is responsible for the detail design and construction of ships' hulls, their strength and stability, hull auxiliaries, fittings and equipage. In connection with the same parts he is charged with their inspection in ships building by private contract, with their construction in ships building in navy yards, with their repair in ships in commission, with their maintenance and preservation in ships out of commission, and wM;h the preparation of specifications ror and the inspection of all material necessary for these various purposes. ing is charged with the responsibility for the design, the construction, and the maintenance in good condition of the propelling machinery of vessels of the Navy ; of their electric light and power equipment, except of motors installed by other bureaus ; of radio stations and their equipment on shore and of the radio equipment afloat ; of heating and refrigerating apparatus; of distilling apparatus ; of the interior communication system, comprising telephones, call bells, etc., and of electric signaling apparatus; of aeroplane motors, motors for small In carrying out this work it has indirect control of the shops of the machinery division in navy yards and has supervision and control of the Engineering Experiment Station at Annapolis, the Aeronautic Motor Laboratory at Washington and of laboratories for other purposes in navy yards, and of the fuel oil testing plant at Philadelphia. system of interior communications. It is specifically charged with the design, supply, installation, maintenance, and repair of all means of interior and exterior electric signal communications (except range finders and battle-order and range transmitters and indicators), and of all electrical appliances of whatsoever nature on board naval vessels, except motors and their controlling apparatus used to operate the machinery belonging to other bureaus. It has charge of the design, manufacture, installation, maintenance, repair, and operation of wireless telegraph outfits on board ship and of wireless telegraph outfits and stations on shore. (See "Radio It has charge of the design, manufacture, installation, maintenance, repair, and operation of aeroplane motors and propellers and their attachments. the Engineering Experiment Station. It designs the various shops at navy yards and stations where its own work is executed, so far as their internal arrangements are concerned. sonnel of the Navy and Marine Corps, numbering now over 100,000. Not only is sickness cared for, hospital or sick-bay treatment provided, necessary operative measures undertaken, but also those in sound health are safeguarded in life and limb as far as modern science can avail. To this end Surgeon General W. C. Braisted has under him a Medical Corps authorized up to a total of over 600, a Dental Corps, a Nurse Corps, and a Hospital Corps of an authorized strength, of over 3,000. In addition he has available for call Medical and Dental Reserve Corps composed of physicians and dentists in civil life who have patriotically offered their services in case of national emergency. These forces are directed by the Surgeon General, as head of the Bureau of Medicine and Surgery. He has charge of the upkeep and operation of all naval hospitals, numbering at present eighteen, situated not only within the continental limits of the United States, but also in our insular possessions. He has under consideration all questions concerning the health, the hygiene, and sanitation of the service, ashore and NAVAL MEDICAL SCHOOL, WASHINGTON, D afloat. One or more medical officers are carried on all ships operating singly, and on flagships of destroyer and submarine flotillas. The Medical Corps in addition undertakes all physical examinations for the service at the many recruiting stations throughout the country, and on board ships and at naval stations and yards. It passes professionally upon all applicants for .enlistment or promotion in the Hospital Corps, and educates and supervises the members of this corps during the entire tenure of service. To this end two excellent Hospital Corps Training Schools have been all of the personnel under his charge to their respective duties, keeping himself constantly in touch with all specially qualified, in various professional lines. He also has charge of the upkeep and operations of the three Naval Medical Supply Depots (Brooklyn, Mare Island atid Canacao), medical laboratories, dispensaries, and technical schools for the Medical and Hospital Corps. The Naval Medical School, in connection with the Naval Hospital, Washing- ton, D. C., provides most valuable post-graduate courses, and laboratory facilities for research and investigation. One of the most valuable assets of the Medical Department is the Hospital Ship "Solace," attached to the Atlantic Fleet, and even more so will be the magnificent new hospital ship authorized by the Sixtyfourth Congress. In addition to the many above enumerated duties and responsibilities, the Surgeon General requisitions for all supplies, medicines, instruments, etc., used in the Medical Department of the Navy, and he has control of the preparation, reception, storage, care, custody, transfer, and issue of all supplies of every kind used in the Medical Department for its own purposes. And lastly, the numerous gallant activities on foreign shores which have made the name of the U. S. Marine Corps justly famous, are always attended by their quotas of efficient, self-sacrificing, and heroic members of the Medical and Hospital Corps of the U. S. Navy. BUREAU OF SUPPLIES AND ACCOUNTS The duties of the Bureau of Supplies and Accounts comprise all that pertains to the purchase, receipt, care, issue and accounting for all supplies and materials for the Navy, which include provisions, clothing, coal, oil and general supplies; the preparation of standard specifications for all supplies ; the shipment thereof, including transportation of coal and fuel oil and the location of the sources of supply. They also comprise the audit of property returns ; audit and payment of vouchers under contract ; payment of traveling expenses, gratuity claims and allotments made by officers and enlisted men, and payments to the Naval Reserve; the recording of expenditures of money under the several appropriations and the distribution of costs to the various activities of the Naval establishment. This bureau also administers the Commissary Department of the Navy and is responsible for procuring and issuing all food supplies to the enlisted men; it likewise operates the two naval clothing factories where articles of uniform and clothing are manufactured for the men. The Hydrographic Office carries and navigational data from maron marine surveying in foreign iners, professional publications, Gov waters ; gathers hydrographic ernment officials, etc., at home and abroad: prepares, prints, and issues navigational charts of foreign waters to the Navy and other public services and sells them to the merchant marine and the public; sim- ilarly with regard to books of sailing directions for foreign waters and manuals and tables for navigators, except that their printing is done at the Government Printing Office. thorized the President to appoint an officer in the Navy Department to be called "the Solicitor and Naval Judge Advocate General." The appointee pursuant to this act was carried on the Navy Register until 1870 when the Department of Justice was established. The act establishing the Department of Justice (June 22, 1870) provided that "the Solicitor and Naval Judge Advocate General, who shall hereafter be known as the Naval Solicitor," should be transferred to the Department of Justice. The incumbent's name was then dropped from the Navy Register and placed upon the rolls of the Department of Justice. At his death in 1878 he was succeeded by an Acting Judge Advocate General, whose office was in the Navy Department until June 8, 1880, when the office of the Judge Advocate General of the Navy, as a part of the Department of the Navy, was established. The duties of the Judge Advocate General of the Navy are set forth in detail in the United States Navy Regulations, 1913, as follows : "The duties of the Judge Advocate General of the Navy shall be to revise and report upon the legal features of and have recorded the proceedings of all courts-martial, courts of inquiry, boards of investigation, inquest, and boards for the examination of officers for retirement and promotion in the naval service; to prepare charges and specifications for courts-martial, and the necessary orders convening courts-martial in cases where such courts are ordered by the Secretary of the Navy ; to prepare court-martial orders promulgating the final action of the reviewing authority in court-martial cases; to prepare the necessary orders convening courts of inquiry in cases where such courts are ordered by the Secretary of the Navy, and boards for the examination of officers for promotion and retirement, and for the examination of candidates for appointment as commissioned officers in the Navy other than midshipmen, and to conduct all official correspondence relating to such courts and boards. "It is also the duty of the Judge Advocate General to examine and report upon all questions relating to rank and precedence, to promotions and retirements, and to the validity of the proceedings in court-martial cases, all matters relating to the supervision and control of naval prisons and prisoners [disciplinary ships and detentioners] ; the removal of the mark of desertion; the correction of records of service and reporting thereupon in the Regular or Volunteer Navy ; certification of discharge in true name; pardons; bills and resolutions introduced in Congress relating to the . personnel and referred to the department for report, and the drafting and interpretation of statutes relating to the personnel ; references to the Comptroller of the Treasury with regard to pay and allowances of the personnel ; questions involving points of law concerning the personnel ; proceedings in the civil courts in all cases concerning the personnel as such ; and to conduct the correspondence respecting the foregoing duties, including the preparation for submission to the Attorney General of all questions relating to subjects coming under his own cognizance which the Secretary of the Navy may direct to be so referred." has also recently been assigned to the office of the Judge Advocate General, and he is required to examine and report upon questions of international law. Because of the present European conflict and the strained relations between this country and Mexico, many intricate questions of present moment have arisen, such as the interference with American mail, removal of ex-enlisted men of the naval service from American ships, attempts by belligerent ships to board naval auxiliaries, the exercise of visit and search by them in territorial waters, etc. The subjects of the treatment of prisoners of war, while under the jurisdiction of the Navy Department, and of belligerent ships and individuals interned in this country, and the formulation of regulations to cover same, have also been BOARD OF INSPECTION AND SURVEY The Board of Inspection and Survey is charged, under specific directions in each case, with con- tions render such inspections necessary or desirable; with the inspections of motorboats for coast defense as they come from the works of the builders ; with the survey and inspection of all naval vessels in service at least every three years and at such other times as condi- the Board of Inspection and Survey, working with certain Army officers, constitutes a Board for the Inspection of Merchant Auxiliaries. The board operates both directly and through sub-boards. The duties of the Solicitor comprise and relate to examination and report upon questions of law, including the drafting and interpretation of statutes, and matters submitted to the accounting officers not relating to the personnel ; preparation of advertisements, proposals, and contracts ; insurance ; patents ; the sufficiency of official, contract, and other bonds and guaranties ; proceedings in the civil courts by or against the Government or its officers in cases relating to material and not concerning the personnel as such ; claims by or against the Government; questions submitted to the Attorney General, except such as are under the cognizance of the Judge Advocate General ; bills and congressional resolutions and inquiries not relating to the personnel and not' elsewhere assigned ; the searching of titles, purchase, sale, transfer, and other questions affecting lands and buildings pertaining to the Navy ; the care and preservation of all muniments of title to land acquired for naval uses ; and the correspondence respecting the foregoing duties; and rendering opinion upon any matter or question of law referred to him by the Secretary or Assistant Secretary. The Major General Commandant of the Marine Corps is responsible to the Secretary of the Navy for the general efficiency and discipline of the corps; makes such distribution of officers and men for duty at the several shore stations as shall appear to him to be most advantageous for the interests of the service ; furnishes detachments for vessels of the Navy according to the author- ized scale of allowance: issues orders for the movement of officers and troops, and such other orders and instructions for their guidance as may be necessary ; and has charge and exercises general supervision and control of the recruiting service of the corps, and of the necessary expenses thereof, including the establishment of recruiting stations. SECRETARY OF THE INTERIOR THE Secretary of the Interior is charged with the supervision of public business relating to patents for inventions, pensions and bounty lands, the public lands and surveys, the Indians, education, the Geological Survey, the Reclamation Service, the Bureau of Mines, national parks, distribution of appropriations for agricultural and mechanical colleges in the States and Territories and certain hospitals and eleemosynary institutions in the District of Columbia. By authority of the President the Secretary of the Interior has general supervision over the work of completing the survey of routes for railroads in the Territory of Alaska. He also exercises certain other powers and duties in relation to the Territories of the United States. In the absence of the Secretary the First Assistant Secretary becomes Acting Secretary. He is especially charged with supervision of the business of the General Land Office, including cases appealed to the Secretary of the Interior from decisions of that bureau involving public lands ; applications for easements or rights of way for reservoirs, ditches, railroads, telephone and power-transmission lines; selections of public lands under grants made by Congress to aid in the construction of railroads and wagon roads, for reclamation, and for the benefit of educational and other public institutions, etc. Indian affairs affecting the disposal of the public domain are under his supervision. He considers proposed legislation pertaining to matters under his administration. From time to time duties in connection with the affairs of other bureaus of the department are assigned to him. The Assistant Secretary has general supervision over all matters concerning the Indian Office (except those which relate to the work of the General Land Office and are forwarded through that office), the Patent Office, the Bureau of Mines, the Pension Office (including appeals from the decisions of the Commissioner of Pensions), the execution of contracts and the approval of vouchers covering expenditures of money for the eleemosynary institutions under the Department of the Interior in the District of Columbia (including Saint Elizabeth's Hospital, formerly the Government Hospital for the Insane), and various miscellaneous matters over which the department has jurisdiction. He also considers proposed legislation pertaining to the department. This officer is charged with the general supervision of matters relating to the eleemosynary institutions under the Department of the Interior in the District of Columbia, the Bureau of Education, the national parks, national monuments, and the Territories. As the chief executive officer of the department and the administrative head of the Office of the Secretary the chief clerk has supervision over the clerks and other employees of the department (including the watch, mechanical and labor forces), enforces the general regulations of the department, and is superintendent of the several buildings occupied by the department. He also supervises the classification and compilation of all estimates of appropriations. The detailed work relating to eleemosynary institutions in the District of Columbia under the Department of the Interior, the office of the returns clerk, and miscellaneous matters is done in his office. During the absence of the Secretary and Assistant Secretaries he may be designated by the Secretary to sign official papers and documents. charged with the administration of the patent laws, and supervision of all matters relating to the granting of letters patent for inventions, and the registration of trade-marks. He is by statute made the tribunal of last resort in the Patent Office, and has appellate jurisdiction in the trial of interference cases, of the patentability of inventions, and of registration of trade-marks. The duties of the Patent Office or its functions with respect to the inventor may be classified under a few heads. Each of these is of great importance and it is thought that the simplicity of the classification may aid somewhat in understanding fully just what the Patent Office does for an inventor. In the first place, it is the keeper of records, maintaining as it does in well classified form the patents is- desired by the public. The registration of trade-marks and labels and the granting of patents for designs also come within the duties of the Patent Office, as well as the recordation of assignments and other instruments in writing affecting the title to patents. It also maintains among its records the pending applications for patents, which are not open to pub- the patents issued by numerous foreign nations which issue Letters Patent for inventions. Incidentally, it permits the inspection of these records by inventors or those acting for them and also furnishes certified and uncertified copies of so lie inspection except to the applicant or those acting by his authority, and forfeited and abandoned applications which, like the pending applications, are not open to public inspection. the propriety of issuing patents on the same, this procedure including appeals within the Patent Office from the Primary Examiners to the Board of Examiners-in-Chief, thence to the Commissioner and thence to the Court of Appeals of the District of Columbia, the Commissioner in appeals to the court being represented usually by one of his law examiners. The Patent Office also includes the court of first resort in interference cases, that is to say, cases wherein two or more inventors are claiming the same patentable subject matter, and it is for the Patent Office to decide whether patent shall issue to the applicant whom it may be determined was first to make the invention. This procedure also contemplates appeals to the Board of of Appeals. It is believed that under the foregoing heads all of the functions of the Patent Office can be classified. The course of a patent application through the Patent Office is ordinarily a simple one. The application, including the petition, specification and oath and drawing and the first Government fee of $15, being deposited with the Financial Clerk, the application papers and drawings find their way to the application room and draftsmen's room, and when the application is found in proper form is forwarded by the chief of the application room to the Primary Examiner in whose class the particular invention is found to belong. The application is then examined in the order of its filing in such Examiner's division, and if it be found in condition for allowance, or when it is so found, it is transmitted to the Issue Division^ which issues a circular of allowance. Then if the second Government fee of $20 be paid into the Patent Office within six months from the date of allowance of the application, the patent will in a few weeks issue and be forwarded to the applicant or his attorney. If objections are found to the application either in form or in substance, considerable time is involved in many cases in adjusting these matters to bring the application into condition for allowance or for final rejection. The Primary Examiner, through one of his assistants, considers the application in the first instance, and if it is found allowable by the Primary Examiner, either in first form or as amended, the case passes to the Issue Division without consideration by those higher in authority. On the other hand, if objections relating to form are found these may be reviewed by petition to the Commissioner direct. If the objections go to the merits, such for instance as a rejection on the ground that the invention is not new in view of any particular reference cited, appeal may be taken to the Board of Examiners-in-Chief. A petition relating to form involves no Government fee, while a petition affecting the merits and going to the Board of Examiners-in-Chief calls for a Government fee of $10. Such is the course of a patent application when actually filed. To aid inventors and their attorneys in determining the probable novelty of any particular invention, the Patent Office maintains a Search Room containing the U. S. patents classified according to the official practice and arranged in suitable stacks or racks so that if the invention be, for instance, a Nut Lock, the searcher may secure the bundle containing patents for such devices, or if it be a dynamo or a telephone, he can secure the bundle having the particular character of such devices to which the invention he is searching relates. The Patent Office is not a bureau of information and does not undertake to answer miscellaneous inquiries relative to patents, nor to express any opinion in advance of the filing of a formal application for patent as to the patentability of any particular invention. The Pension Bureau, which is said to be the largest bureau in the Government service, and the only bureau which occupies a building erected for its especial use, is the active agency through which there was paid out last year one There are now on the pension roll about four hundred thousand males and three hundred thousand widows. Death is making sad havoc among their numbers. Last year there At times some magazine article complains of the amount of pensions, but it will be noticed by those who have knowledge of the recent allowances in Canada, Australia and Great Britain, that the amount paid to an individual here is less than that now paid in other countries. The modern tendency is to care more for the private soldier. This is justified by two viewpoints — one is that he is the most valuable component part of an army and should be kept efficient and encouraged both by good care of him and of his family. The other reason is humanity, which now pays more regard to the humbler member as a unit of society. Besides the Commissioner, there are 1,200 employees transacting the necessary business of the Pension Bureau. Applications are not so numerous as formerly, yet there were more than sixty-five thousand received during last year, and 68,549 new certificates were issued. The total cost of administration was only 1 per cent of the pensions paid out, which is lower than ever before. It is believed that, under the present administration, the pension laws have been faithfully executed in an efficient and economic manner. that to which the law entitled him. An additional pension of $10 per month has been allowed to soldiers and sailors holding medals of honor. the widows of Mexican and Civil War soldiers who are seventy years of age, or who were married to the soldier during the period of his service. That act also makes pensionable widows of Civil Wai soldiers who married prior to June 27, 1905, and certain remarried widows. fied. The expense of executing vouchers has been eliminated — a saving to the soldiers themselves of many thousands of dollars — and they are no longer required to exhibit their certificates each time of indorsement of the check. The Commissioner of Indian Af- Alaska), their education, lands, fairs has charge of the Indian tribes moneys, schools, purchase of supof the United States (exclusive of plies, and general welfare. collects statistics and general information showing the condition and progress of education, issues an annual report, a bulletin in several numbers annually, and miscella- the schools for the education of native children in Alaska ; supervises the reindeer industry in Alaska, and administers the endowment fund for the support of colleges for the benefit of agriculture and me- oldest and in many respects the largest and most important Bureau of the Department of the Interior; it has jurisdiction over all matters pertaining to the survey and disposition of the public lands of the United States, exclusive of lands in the insular possessions; also, in point of number of cases and values involved, the General Land Office, in the determination of questions with respect to title to public lands, exercises judicial functions of vast importance. Its internal organization consists of the Washington office, the local United States land offices, the offices of Surveyors General, the field surveying organization and the field 'service organization, making a total of about one hundred and twenty-five branch offices and headquarters, principally in the Western States. This bureau employs altogether about sixteen hundred people. Contrary to popular belief the business of this department has not decreased in recent years, and, owing to new legislation and change of governmental policies, its work is increasingly complicated and exacting. NATIONAL BUREAU OF MINES The National Bureau of Mines, tive July 1, 1910. This act was under - the Department of the In- amended by an act, effective Febterior, was created by act of Con- ruary 25, 1913, which provides that gress, approved May 16 and effec- the Bureau of Mines is to be a •The work of the United States Reclamation Service and of the United States Geological Survey is of such importance that special chapters on these subjects are given in the first part of the book. See pages 87 and 119. bureau of mining, metallurgy and mineral technology, and that the duty of the bureau shall be to conduct scientific and technologic investigations concerning mining, and the preparation, treatment and utilization of mineral substances with a view to improving health conditions and increasing safety, efficiency and economic development, and conserving resources through the prevention of waste in the mining, quarrying, metallurgical and other mineral industries ; to inquire into the economic conditions affecting these industries ; to investigate explosives and peat ; and on behalf of the Government to investigate the mineral fuels and unfinished mineral products belonging to, or for the use of, the United States, with a view to their most efficient mining, preparation, treatment and use; and to disseminate information concerning these subjects. The act further provides that no member of the bureau shall have any personal or private interest in any mine or the products of any mine under investigation, or shall accept employment from any private party for services in the examination of any mine or private mineral property, or issue any report as to the valuation or the management of any mine or other private mineral property. This provision, however, does not apply to the temporary employment in a consulting capacity of experts whose principal practice is outside of the bureau. Another section of the act directs that a reasonable fee covering necessary expenses shall be charged by the bureau in making tests other than those for the Government of the United States or State governments. The inquiries and investigations being carried on by the bureau under the provisions of this act cover a wide variety of subjects and are too numerous to mention here. The chief experiment station of the bureau is in Pittsburgh, Pa. Work relating to the causes and prevention of mine explosions, to which the bureau has given special attention, and other mining problems, includes laboratory tests, the examination of mines and experiments in an experimental mine near Pittsburgh under conditions simulating those of commercial operations. tions and educational work for greater safety in mining, the Bureau of Mines has six mine-rescue stations situated in different mining regions of the country, and also operates eight mine-rescue cars and two rescue trucks. These cars and trucks, manned by trained crews, are constantly ready to give aid, when requested by State officials, at a mine disaster. The cars move from point to point in the regions in which they are stationed, and the crews demonstrate safe methods of mining and the use of rescue apparatus and first-aid appliances. An act of Congress, approved March 3, 1915, authorizes the establishment and maintenance under the Bureau of Mines of ten mining experiment and seven mine safety stations (mine rescue cars), in addition to those already established, not more than three of each class of stations to be established in any one year. It is expected that through these stations the safety work of the bureau will be made more effective, and that the investigations for increasing efficiency in the handling and utilization of mineral resources will be enlarged and extended. The Assistant Secretary of Agri- assists in the general supervision of culture becomes Acting Secretary in the work of the department at all the absence of the Secretary and times. SUPPLY DIVISION The chief of the supply division poses of property turned in by the purchases and distributes stationery various offices when it is of no furand miscellaneous supplies and dis- ther use to them. CHIEF U. S. WEATHER BUREAU THE history of the Weather ings; the display of weather, frost Bureau as an organization be- and flood signals for the benefit of gins with the passage of the agriculture, commerce and navigaact of Congress, approved February tion; the gaging and reporting of 9, 1870, which authorized and re- rivers; the maintenance and operaquired the Secretary of War to pro- tion of seacoast telegraph lines and vide for the taking of meteorological the collection and transmission of observations throughout the United marine intelligence for the benefit States and for giving telegraphic of commerce and navigation ; the renotice on the Takes and seacoast of porting of temperature and rainfall the approach of storms. Since its conditions for the cotton interests, establishment the scope of its work and the taking of such meteorologihas been gradually extended until cal observations as may be necesnow its functions as defined by law sary to establish and record the cliembrace the forecasting of the matic conditions of the United weather ; the Issue of storm warn- States, or are essential for the prop- er execution of the foregoing duties. From the date of its organization until July 1, 1891, the weather service was conducted as a branch of the Signal Corps, under the direction of the Chief Signal Officer of the Army, but on the date mentioned it was transferred to the Departments of Agriculture and made a bureau of that Department, under its present designation. best known to the general public sphere. The results of the twicedaily observations are immediately telegraphed to the Central Office at Washington, D. C., where they are charted for study and interpretation by experts trained to forecast weather conditions which may be expected to prevail during the following thirty-six to forty-eight hours. From these data the forecaster, by comparison with preceding reports, is able to trace the paths of storm areas from the time of their appear- CENTRAL OFFICE OF THE V. 8. WEATHEK BUREAU, WASHINGTON, D. C. through the exercise of its principal and most important function, the issue of the daily weather forecasts. These forecasts are based upon simultaneous observations of local weather conditions taken daily at 8 A. M. and 8 P. M., 75th meridian time, at about two hundred regular observing stations scattered throughout the United States and the West Indies, and upon similar reports received daily from various points in other parts of the northern hemi- ance to the moment of observation, and approximately determine and forecast their subsequent courses and the resultant weather conditions. Forecast centers have also been established at Chicago, 111.; New Orleans, La. ; Denver, Colo. ; San Francisco, Cal. ; and Portland, Ore. Within two hours after the morning observations have been taken the forecasts are telegraphed from the forecast centers to about 1,700 principal distributing points, whence they are further disseminated by telegraph, telephone and mail. The forecasts reach nearly 100,000 addresses daily by mail, the greater part being delivered early in the day, and none later, as a rule, than 6 P. M. of the day of issue, and are available to more than 5,000,000 telephone subscribers within an hour of the time of issue. This system of forecast distribution is wholly under the supervision and mainly at the expense of the Government, and is in addition to and distinct from the distribution effected through the press associations and the daily newspapers. The rural free mail delivery system and rural telephone lines are also being utilized to bring within the benefits of this system a large number of farming communities. A careful comparison of the forecasts with the weather conditions occurring over the regions and during the periods covered The daily weather maps, based on the data contained in the morning telegraphic reports, are issued as soon as practicable after these reports are received. On these maps the salient features of the current weather conditions throughout the country are graphically represented, accompanied by a synopsis of these conditions; in addition to which complete reports- from all the observing stations are presented in tabulated form. In order that all sections of the country may receive weather data, maps or bulletins containing the data in tabulated form, are issued from about one hundred of the larger stations. The ocean meteorological service aims to collect, through the co-operation of vessel masters and others, meteorological observations at sea. The recent development in the art of radio-telegraphy has made possible the transmission of meteorological observations made by ships at sea to shore stations, thence by land lines to a central meteorological service. The Weather Bureau has organized a system of meteorological observations on vessels navigating the coastal waters of the middle and South Atlantic States, the Gulf of Mexico, and the Caribbean Sea, the primary object being to gain information of sub-tropical storms which occasionally traverse the waters above named. Distribution of weath- RECORDER er information, forecasts, and warnings is made daily by radio service through the co-operation of the radio service of the United States Navy. Although the two hundred regular observing stations, each representing about 16,000 square miles of territory, furnish sufficient data upon which to base the various forecasts, observations at many intermediate points are necessary before the climatology of the United States can be properly studied. This need has given rise to the establishment of an important and interesting feature of the Weather Bureau in its Climatological Service. This service is divided into forty-four local sections, each, as a rule, covering a single State, and having for its center a regular observing station. These centers collect temperature and rainfall observations from more than 4,000 co-operative stations and publish these data in the form of monthly reports which are given a widespread distribution. During the growing season (from April to September, inclusive) each section also receives mail reports from numerous correspondents (aggregating for all sections about 7,500) concerning the effects of the weather upon crops and farming operations, these reports being used to compile data for weekly bulletins. During the same season the Central Office at Washington issues a National Weather and Crop Bulletin containing a series of charts graphically illustrating current and normal conditions of temperature and rainfall for the entire country, a general summary of the weather, and brief reports on the condition of the crops for each State. Throughout the cotton, corn, wheat, sugar and rice producing sections designated centers receive telegraphic reports of rainfall and daily extremes of temperature from nearby points for publication in bulletin form, each local center receiving condensed reports from all others. By the assistance of several thousand co-operative observers, many of whom have maintained local records for long periods, the Weather Bureau endeavors to collect special local data and thus perfect the records that are needed for the study of the relation between climate and agriculture, forestry, water resources, and other kindred subjects. The results of these observations appear in detail in monthly and annual re- tion centers. A division of the bureau, known as the Division of Agricultural Meteorology, has for its lines of work the application of meteorology to the needs and interests of agriculture; conducting studies of meteorological and climatic conditions in their relation to agriculture and the growth and yield of crops ; conducting investigations of the effect of weather and climate upon plant growth; determination of the distribution of frost warnings and forecasts to special agricultural interests ; conducting studies for the protection of crops and orchards from frosts, and distributing information as to the effect of the weather and climate on crops, through the medium of the National Weather and The Monthly Weather Review, which has been published regularly since January, 1873, and. which contains elaborate meteorological tables and charts showing the weather conditions for the month over the tries. The reports of the sections of the Climate and Crop Service, showing in detail the climatic conditions of the month. The Weekly Weather and Crop Bulletin, which gives in detail the weather conditions that have prevailed throughout the country during the week and its effects upon the crops. The occasional bulletins, now numbering about seventy, containing the larger reports made by the experts of the service. reau contains about 32,000 books and pamphlets, consisting principally of technical books on meteorology and allied sciences, and of published climatological data from all parts of the world. It is available to all Weather Bureau officials and to students of meteorology generally, who either consult it personally or through correspondence. In addition to its general card catalogue, it keeps up to date a catalogue of the meteorological contents of the principal scientific serials of the world. The apparatus used at Weather Bureau stations for recording weather conditions is largely the result of improvements devised by the Instrument Division, to which is intrusted the care of all standards. The kites, meteorographs, self-registering instruments, and other forms of apparatus devised by the Weather Bureau are favorably known The Bureau has a force of scientists and trained employees engaged in research work in connection with upper air conditions and solar radiation and investigations in seismology. The extent to which the work of the Weather Bureau, in the collection and publication of data and the issue of weather forecasts and warnings, affects the daily life of the people and becomes a factor in their various avocations and business enterprises, already very great, is increasing yearly. casts are so numerous and well known as to call for no remark, but the value to the manifold business interests of the country of the publication of weather data and the dissemination of warnings of exceptionally severe and injurious weather conditions, such as storms and hurricanes, cold waves, frosts, floods, heavy rains and snows, is not so generally understood. Of the warnings mentioned, those of storms and hurricanes, issued for the benefit of marine interests, are the most important and pecuniarily valuable. Storm warnings are displayed at nearly 300 points along the Atlantic, Pacific and Gulf coasts and the shores of the Great Lakes, including every port and harbor of any considerable importance; and so nearly perfect has this service become that scarcely a storm of marked danger to maritime interests has occurred FORECASTING THE WEATHER AT THE WEATHER BUREAU, WASHINGTON, D. C. for years for which ample warnings have not been issued from twelve to twenty-four hours in advance. The sailings of the immense number of vessels engaged in our ocean and lake traffic are largely determined by these warnings, and those displayed for a single hurricane are known to have detained in port on our Atlantic coast vessels valued, with their cargoes, at over $30,000,000. The warnings of those sudden and destructive temperature changes known as cold waves are probably next in importance. These warnings, which are issued from twenty-four to thirty-six hours in advance, are disseminated throughout the threatened regions by means of flags displayed on regular Weather Bureau and sub-display stations, by telegraph, telephone, and mail service to all places receiving daily forecasts, and to a large number of special addresses in addition. The beneficial results of these warnings are manifold. Precautions are taken for the safeguarding of personal comfort and health, and the protection from freezing of produce of all kinds, steam and water pipes, hot ' house plants, and flowers. Railroads regulate the size and movement of their freight trains, ice men prepare for harvesting, and many plans for business and pleasure are made on the expectation of the conditions forecast. The warnings issued in January, 1896, for a single cold wave of exceptional severity and extent, resulted, according to reports, in the saving of over $3,500,000 in the protection of property from injury or destruction. The warnings of frost and freezing weather are also of immense value, particularly to the fruit, sugar, tobacco, cranberry and market gardening interests. The early truck raising industry, so extensively carried on in the regions border- ing on the Gulf and South Atlantic coasts, and in Florida, and which has increased so greatly in the last few years, is largely dependent for its success on the co-operation of the Weather Bureau in this particular, and the growers of citrus and other fruits liable to injury by frosts or freezing weather have invested large sums in tents, screens, heating, smudging, and irrigating apparatus for the protection of their groves and orchards, which they put into use when notified by the bureau of the expected occurrence of injuriously low temperatures. The commerce of our rivers is greatly aided and lives and property in regions subject to overflow are protected by the publication of the river stages and the issue of river and flood forecasts based on reports received from about five hundred special river and rainfall stations. On the occasion of the flood of 1897 in the lower Mississippi Valley live stock and other movable property to the estimated value of about $15,000,000 was removed from the inundated regions prior to the flood, as a result of the warnings by the bureau a week in advance of its occurrence. In the raisin-growing districts of California rain forecasts are of great value. The raisin crop while growing is extremely susceptible to injury from rain, and the warnings enable the producers to protect the fruit by stacking and covering the trays. The accuracy of the rain forecasts for this region and the system for their distribution have been such that practically no loss from this cause has occurred for years. Shippers of perishable produce and goods liable to injury by heat or cold are guided largely by tho weather reports in making shipments and in directing their movements while on the road. Large dealers in produce, by careful attention to the daily reports and the weekly crop bulletins, inform themselves as to the regions where conditions most favorable for certain crops have occurred, and are thus enabled to judge of the probable supply and purchase to advantage. Constructors of waterworks, bridges, culverts, and sewers consult the rainfall records to ascertain the maximum water flow they will have to allow for. Architects of iron and steel structures and tall buildings study the records of maximum and minimum temperatures and wind ings must be prepared to withstand. From the information as to climatic conditions made known through the reports, invalids and tourists are enabled to select the locations best suited to their health and pleasure, and manufacturers and agriculturists the regions best adapted for the carrying on of their particular industries. By the recent expansion of the system of snowfall observations throughout the mountain regions adjacent to the Great Plains, it has been made possible to forecast the probable flow in the rivers of the arid regions, a factor of great importance in irrigation. The records of the bureau are of frequent use as evidence in courts of law, for which purpose they have been decided competent evidence by the Supreme Court of the United States. The conduct of the regular stations of observations outside of Washington requires the constant services of about six hundred, and the business of the Central Office at Washington of about two hundred employees. The annual disbursements of the bureau amount to about $1,600,000. The numerous offices of the bureau throughout the country are always open during business hours and the public are cordially invited to visit them and avail themselves of the information contained in the records there on file. The Bureau of Animal Industry has charge of the work of the department relating to the live-stock industry. In general it deals with the investigation, control, and eradi- cation of diseases of animals, the inspection and quarantine of live stock, the inspection of meat and meat food products, and with animal husbandry and dairying. The Bureau of Plant Industry studies plant life in all its delations to agriculture. The scientific work of the bureau is divided into twentyseven distinct groups, over each of which is placed >a scientifically trained officer, who reports directly to the chief and assistant chief of the bureau. The work of the bureau is conducted on the project plan, the investigations under each of the offices being arranged by group projects consisting of closely related lines of work, which group of The Forest Service is charged with the administration and protection of the 152 National forests. These forests comprise over 155 million acres of laud, have an estimated stand of 600 billion board feet of timber, supply range for 14 million head of livestock, and contain water power valued at about ?200,000,000. In addition to caring for the National forests, the Forest Service conducts investigations of improved methods of utilizing and marketing all classes of forest products ; carries on studies to determine possible uses for wood waste, and co-operates with private individuals and corporations in solving problems relative to the use of wood in general. Under the provisions of the Weeks Law, the Forest Service examines lands in the Southern Appalachian and White Mountain regions which are offered for sale to the Government and protects and administers such lands after their purchase, in addition to co-operating with various States in forest fire protection. Finally, information in regard to the relation of forests to the general welfare is collected and disseminated. cerned with analytical work and investigation under the food and drugs act, questions of agricultural chem- The Bureau of Soils investigates the relation of soils to climate and organic life ; studies the texture and composition of soils in field and laboratory ; maps the soils ; studies the cause and means of preventing the rise of alkali in soils of irrigated areas, and the relation of soils to seepage and drainage conditions. The Bureau of Entomology studies insects ; experiments with the introduction into the United States of beneficial insects; makes tests with insecticides and insecticide machinery ; identifies insects sent in by Inquirers. It is practically solely a research organization and studies the insects which are ENTOMOLOGY injurious to various crops and domestic animals,, and to man himself, in the hope of learning the cheapest and most effective remedies and preventives. It expends an annual birds and mammals in their relation to agriculture, their food habits, etc., and recommendation ol measures for the preservation of beneficial species and the destruction of harmful species, also experiments Jn fur farming; (2) making biological surveys, study of geographic distribution of animals and plants, and mapping natural life zones; (3) carrying into effect the Federal laws protecting game and regulating the importation of foreign birds and animals; and (4) general supervision of the Federal migratory bird law, DIVISION OP PUBLICATIONS The Division of Publications conducts all business of the department transacted with the Government Printing Office; has general supervision of the printing, indexing, binding, and distribution of publications, and the maintenance of mailing lists. The Bureau of Crop Estimates issues the monthly crop reports based on data collected by salaried field agents and a corps of approximately 150,000 voluntary crop reporters, every State, county and agricultural township being represented. The monthly crop reports contain annual estimates of numbers of different classes of live stock on farms and losses due to disease and exposure, annual estimates of acreage planted and acreage harvested of the principal crops, monthly reports of the condition of about sixty different crops during the growing season, monthly forecasts of yields per acre and total production, monthly reports of farm prices of all crops and classes of live stock, and in December estimates of total production of all the principal crops. The monthly reports of condition and forecasts of production are issued to the press associations in Washington and telegraphed to the Weather Bureau Station Directors in all the States for prompt dissemination to the local press, and at the close of the year annual estimates of crop and live stock production are published in the Yearbook of the Department. LIBRARY The department library contains 137,000 books and pamphlets, including an extensive collection on agriculture, a large and representative collection on the sciences related to standard reference books. Periodicals currently received number 2,337. A dictionary catalogue is kept on cards, which number about 325,000. The librarian has charge of the The States Relations Service of the United States Department of Agriculture administers the Hatch and Adams acts providing Federal aid for the State agricultural experiment stations and the SmithLever act providing for co-operative extension work in agriculture and home economics. It also has charge of the farmers' co-operative demonstration work conducted by the Department of Agriculture, makes investigations relating to agricultural schools, farmers' institutes, and home economics, and directs the work of the agricultural experiment stations in Alaska, Hawaii, Porto Rico and Guam. The service issues Experiment Station Record, a periodical technical review of the world's scientific literature pertaining to agriculture besides various publications relating to its special lines of work. all work within the Department of Agriculture which is of an agricultural nature involving engineering or mechanical principles, together with the supervision of all road work under the Federal Aid Road Act. For carrying out this work the office is divided into two main branches, known respectively as (I) Management and Economics, (2) Engineering, and these are subdivided into lines of work as follows : Management ; Engineering Economics; Road Materials Tests and Research ; Highway Construction and Maintenance; Irrigation; Drainage; Rural Engineering. For convenience in Federal Aid road work ten field districts have been established, and in addition to the general organization there are two general inspectors who report to the director of the office. With regard to character the work may, however, be more conveniently grouped into three general classes, as follows: (1) Education or extension ; (2) investigations or research; and (3) the supervision of the road work under the Federal Aid Road Act, the administration of which was placed by Congress under the Secretary of Agriculture. The educational or extension work includes reaching the people by means of lectures, addresses, the publication of bulletins, the exhibition of models, etc., and thus teaching the economic value of science and experience in the improvement and care of roads, the necessity and the methods for obtaining adequate land drainage, the economic importance of farm irrigation and practical methods, the meaning and possibilities of modern farm conveniences, not for the farm only, but also for the farm home, and the intelligent utilization of farm equipment and machinery. Special advice and assistance is also frequently given where the problems to be solved involve a knowledge of community and co-operative administration and of methods for planning and financing such works as a better system of roads or the irrigation or drainage of a district. Here the questions are specific rather than general and the lecturer gives way to the engineer. Not infrequently the assistance takes the form of an actual demonstration of construction under Government supervision. In fact, the office then becomes practically an object lesson school for road construction, the proper methods of farm irrigation or land drainage. The research and experimental work of the office has become exceedingly important and varied by reason of the many problems, not only in road construction and maintenance to which modern traffic conditions have given rise, but also in connection with the drainage and irrigation of agricultural lands and in the development of the various structures, appliances and equipment necessary for adequately conducting farm operations. Proper co-ordination between the investigations conducted in the laboratories and the results obtained from field experiments and actual practice is constantly sought, and the laboratories have been specially equipped so as to further this object. Under the Federal Aid Road Act of July 11, 1916, the Secretary of Agriculture is authorized to co-operate with the States through their respective State highway departments in the construction and improvement of rural post roads. The act provides for a comprehensive program extending over a period of five years, with an appropriation of $5,000,000 for the fiscal year 1917, and increasing annually by $5,000,000 to $25,000,000 for the fiscal year 1921. The appropriations are apportioned to the several States on the basis of population, area, and mileage of rural free delivery and star routes, each factor having a weight of one-third. The amount apportioned by the Federal Govern- ment must be at least duplicated by the State. The same act also provides for an annual appropriation of $1,000,000 for a period of ten years for the construction of roads and trails within or partly within the national forest reserves. OFFICE OF MARKETS AND RURAL ORGANIZATION This office secures and distributes information regarding the marketing and distributing of farm and non-manufactured food products. It conducts a demonstration telegraphic market news service regarding fruits and vegetables, and selves in matters of rural marketing, credit, insurance, and communication. It co-operates with various States in conducting marketing investigations. Under authority given to the Secretary of Agriculture by law it is responsible to him for the BUTTER AND CELERY OR CHICKENS a service by mail concerning the commercial surpluses of some other less perishable crops. It is beginning a similar service upon live stock and meats. Co-operation proper enforcement of the United States Cotton Futures Act and the Warehouse Act, and in co-operation with the Bureau of Plant Industry of the enforcement of the Grain Standards Act This office is being appreciated. moting the commerce of the United States and its mining, manufacturing, shipping, fishery, and transportation interests. His duties also comprise the administration of the Lighthouse Service and the aid and protection to shipping thereby ; the taking of the census and the col- control of the Alaskan fur-seal, salmon, and other fisheries ; the jurisdiction over merchant vessels, their registry, licensing, measurement, entry, clearance, transfers, movement of their cargoes and passengers, and laws relating thereto, and to seamen of the United States; the regulation of the enforcement and execution of the act of Congress CREATIONS ON LAND lection and publication of statistical information connected therewith ; the making of coast and geodetic surveys ; the collecting of statistics relating to foreign and domestic commerce ; the inspection of steamboats, and the enforcement of laws relating thereto for the protection of life and property ; the supervision of the fisheries as administered by the Federal Government; the supervision and relating to the equipment of ocean steamers with apparatus and operators for wireless communication ; the custody, construction, maintenance, and application of standards of weights and measurements; the gathering and supplying of information regarding industries and markets for the fostering of manufacturing; and the formulation (in conjunction with the Secretaries of Ag- riculture and the Treasury) of regulations for the enforcement of the food and drugs act of 1906 and the insecticide act of 1910. He has power to call upon other departments for statistical data obtained by them. powers and authority possessed or exercised, at the date of the creation of said department, by the head of any executive department in and over any bureau, office, officer, board, branch, or division of the public service transferred to said department, or any business arising therefrom or pertaining thereto, or in relation to the duties and authority conferred by law upon such bureau, office, officer, board, branch, or division of the public service, whether of appellate or advisory character or otherwise, are vested in and exercised by the Secretary of Commerce. The act creating the Department of Labor, approved March 4, 1913, changed the name of the Department of Commerce and Labor to the Department of Commerce. Under the terms of this act the Bureau of Labor, Bureau of Immigration, Division of Naturalization, and Children's Bureau were detached from the Department of Commerce and The Assistant Secretary performs such duties as shall be prescribed from time to time by the Secretary or may be The chief c^erk is charged with the general supervision of the clerks and employees of the department ; the enforcement of the general- regulations of the department ; the superintendency of all buildings occupied by the department in the District of Columbia ; the general supervision of all expenditures from the appropriations for contingent expenses and rents ; the receipt, distribution, and transmission of the mail ; the supervision of the library and the stock and shipping section of the department ; and the discharge of all business of the office of the Secretary not otherwise assigned. The disbursing clerk is charged by the Secretary of Commerce with the duty of preparing all requisitions for the advance of public funds from appropriations for the Department of Commerce to disbursing clerks and special disbursing agents charged with the disbursement of public funds ; the keeping of appropriation ledgers relating to the advance and expenditure of all items of appropriations. He has charge of the issuing, recording, and accounting for Government requests for transportation issued to officers of the department for official travel ; the audit and payment of all vouchers and accounts submitted from the various offices, bureaus, and services of the department (except the Coast and Geodetic Survey and those services having special disbursing agents) ; and the general accounting of the department. APPOINTMENT DIVISION The Chief of the Appointment Division Is charged by the Secretary of Commerce with the supervision of matters relating to appointments, transfers, promotions, reductions, removals, and all other changes in the personnel, including applications for positions and recommendations concerning the same, and the correspondence connected therewith ; the preparation and submission to the Secretary of all material for the Official Register, and the custody of oaths of office, records pertaining to official bonds, service records of officers and employees, correspondence and reports relating to personnel, reports of bureau officers respecting efficiency of employees, and records relating to leaves of absence. «fhe Chief of the Division of Publications is charged' by the Secretary of Commerce with the conduct of all business the department transacts with the Government Printing Office ; the general supervision of printing, including the editing and preparation of copy, Illus- trating and binding, the distribution of publications, and the maintenance of mailing lists. The advertising done by the department is in his charge. He also keeps a record of all expenditures for publishing work of the department and conducts the correspondence it entails. Under the direction of the chief clerk the Chief of the Division of Supplies has personal supervision of all the work incident to the purchase and distribution of supplies for the department proper and for the services of the department outside of Washington, and of the keeping of detailed accounts of all expenditures from the appropriation for con- tingent expenses of the department. He receives, verifies, and preserves the semiannual returns of property from the offices and bureaus of the department which are supplied from the contingent appropriation, and examines and reports on the semi-annual property returns of all other bureaus and services of the department. mestic Commerce is concerned primarily with the collection of information concerning foreign markets and the dissemination of this information for the use and benefit of American commercial interests. For the collection of information the bureau depends chiefly upon the American consular service, upon the ten commercial attaches appointed by the bureau, and upon a corps of fifteen to twenty-five traveling special agents. The consuls submit reports to the State Department on a variety of commercial subjects, and once a year prepare a review of the commercial and industrial activities of the district to which they are assigned. These reports are turned over to the Bureau of Foreign and Domestic Commerce for publication. There are commercial attache's at London, Paris, Berlin, Petrograd, Peking, Melbourne, Rio de Janeiro, Buenos Aires, Lima, and Santiago (Chile). They are attached to the embassies or legations, but confine their attention to commercial affairs. They have been termed "business diplomats" and "ambassadors of industry." This service has recently completed a world-wide survey of the first that has ever been made. The special agents are specialists. If it is desired to learn the possibilities of selling boots and shoes in South America, for instance, a man is selected by examination who knows the business thoroughly, who can speak Spanish fluently, and who can report well what he learns. This man is then sent to South American countries to spend a year or two studying the subject. Since the war started the activities of the special agents have been largely centered in South America and the Far East. The information gathered by the consuls, attaches and agents is distributed from the central office at Washington. The shorter current reports are published in the daily "Commerce Reports," which has a paid circulation of nearly 10,000. The longer and more specialized reports are published in the form of monographs, ranging in length from 16 to 500 pages. There are books of this kind on the cotton-goods markets of nearly every country in the world. The reports of the attaches on the hardware markets are being published in this form. Specific opportunities to secure foreign business are published as "Trade Oppor- tunities," on the back page of "Commerce Reports," with names and addresses omitted. The information withheld can be obtained by any American firm of known standing upon application to the bureau. Hundreds of thousands of dollars worth of business is brought to the United States in this manner. Upon occasion special bulletins are sent to manufacturers and exporters. To facilitate the distribution of trade information the bureau has recently established district offices at New York, Boston, Atlanta, Chicago, St. Louis, New Orleans, San Francisco, and Seattle. What are termed "co-operative offices" have been es- tablished at Philadelphia, Chattanooga, Cincinnati, Cleveland, Los Angeles and Portland, Ore. These co-operative offices are in reality foreign-trade departments of the local chambers of commerce which have made special arrangements to furnish the same information service in their districts as the regular district offices furnish in theirs. The foreign-trade statistics used so extensively in the public press are compiled by the Bureau of Foreign and Domestic Commerce from custom house documents, in co-operation with the Treasury Department. These statistics are published monthly, quarterly, and yearly. CENSUS TABULATING MACHINE ernment, beginning in 1790. The Constitutional requirement of a decennial census is found in Article 1, Section 3, which directs that Rep- resentatives and direct taxes shall be apportioned among the several States according to their respective numbers, as ascertained by actual enumeration, to be made once in ten years. From decade to decade the scope of the census was extended to include not only a great amount of detail with respect to the population but also other entirely distinct lines of inquiry, such as agriculture, manufactures, etc. law made a permanent branch of the Department of the Interior under the name "Bureau of the Census." A year later it was transferred to the newly created Department of Commerce and Labor, and since March 4, 1913, it has been a bureau of the Department of Commerce. The last decennial census covered the subjects of population, agriculture, manufactures and mines and quarries and oil and gas wells. During the years intervening between decennial censuses the bureau conducts decennial inquiries relating to wealth, debt and taxation, to dependent, defective and delinquent classes, to religious bodies, to fisheries and to transportation Dy water; quinquennial inquiries in re- gard to manufactures, central electric light and power stations, street and electric railways and telegraphs and telephones; annual collections of birth and death statistics and of financial and other statistics of cities ; semi-annual inquiries as to stocks of leaf tobacco held by manu- extraordinarily high degree of efficiency, so that by its aid the average output of the clerks engaged in routine tabulation is increased many fold. The illustration on the preceding page shows the machine Reporters waiting to rush to telephones facturers and dealers ; and periodical collections, at intervals averaging less than one month, of statistics relating to cotton and cottonseed. Special inquiries are occasionally devolved upon the bureau by Congress, by the President or by the Secretary of Commerce. by which the final process of mechanical tabulation is performed. Punched cards are automatically fed into this machine at the rate of 400 or more per minute, and the statistical facts indicated on them by the positions of the holes are electrically recorded with unerring accuracy. Standards are as follows: The custody of the standards ; the comparison of the standards used in scientific investigations, engineering, manufacturing, commerce, and educa- tional institutions with the standards adopted or recognized by the Government ; the construction, when necessary, of standards, their multiples and subdivisions; the testing and calibration of standard measur- ing apparatus ; the solution of problems which arise in connection with standards; the determination of physical constants and properties of materials, when such data are of great importance to scientific or manufacturing interests and are not cipa,! government within the United States, or for any scientific society, educational institution, firm, corporation, or individual within the United States engaged in manufacturing or other pursuits requiring the use of standards or standard measuring OF STANDARDS to be obtained of sufficient accuracy elsewhere; and other investigations as authorized by Congress. The bureau is authorized to exercise its functions for the Government of the United States, for any State or muni- instruments. For all comparisons, calibration tests, or investigations, except those performed for the Government of the United States or State governments, a reasonable fee will be charged. over merchant shipping through the Bureau of Navigation of the Department of Commerce. To engage in trade or in the fisheries, vessels in the United States must first secure a permit from the Government ; that is to say, vessels of which the contents are 500 cubic also decides all questions about measuring the cubical contents of the vessel, a somewhat intricate task performed by custom house officers. As various charges, Federal, local and private, are based on the size of vessels, the Federal Government through the Bureau of Navigation endeavors to see that the rules of measurement are enforced uniform- BUREAU OF NAVIGATION FIEET feet or more. Smaller boats are not required to get this permit, nor are barges, lighters and similar craft employed only in harbors or on canals and waters not subject to Federal jurisdiction. The issue of these permits is based on the clause of the Constitution which gives the Federal Government the power to regulate commerce with foreign nations and between the States. These permits are called registers if the vessel is to engage in foreign trade, and enrollments or licenses if the vessel is to engage solely in trade between American ports. Collectors of Customs issue annually these papers, of which there are over 26,000, but the Bureau of Navigation superintends the work and decides all doubtful questions. The Bureau ly. Foreign nations follow the- same general method of issuing documents to their ships and measuring their size as does the United States — indeed, the laws of the United States on ships' registers date back to the time of Alexander Hamilton, first Secretary of the Treasury, who The only important tax imposed by the Federal Government on ships in foreign trade is a duty on their tonnage or cubical contents, which may not exceed annually 30 cents a ton, or 100 cubic feet, on ships in trade with the more remote continents, or 10 cents annually on ships in trade with the nearby foreign ports of North America and adjacent islands. This Federal tax law is also enforced by Collectors of Customs tinder direction of the Bu< reau of Navigation. The tax is im-; posed uniformly on American antf, foreign ships. Every maritime nation supervises the labor contracts entered into by the seamen on its merchant vessels engaging in foreign trade. This supervision is to prevent frauds upon seamen, to prevent their being left stranded in foreign ports and to enable the seaman to know in advance just what work he has agreed to perform, the course and duration of the voyage, the fare he is to receive on board and the pay he is to get. These contracts are made in writing on printed Government forms and are signed by a shipping commissioner or collector of customs as a representative of the Government. When the contract has been performed and the voyage ended, the seamen are paid off and discharged before the shipping commissioner. Governments are specially interested in the whereabouts and welfare of their merchant seamen, as in many countries they are reckoned an asset in national defense. During the past fiscal year 487,524 officers and men signed such agreements and were later paid off and discharged by the commissioners, some men appearing in the total as often as the number of voyages they made. It requires 60,000 officers and men to man the oceangoing merchant ships and yachts under the American flag, and the Bureau of Navigation of the Commerce Department has general supervision over the shipping and discharge of crews under the method outlined. The American Navy now has about 55,000 enlisted men, and officers and the Marine Corps bring the total beyond the number in the merchant service. When the warships recently ordered are in commission four or five years hence the Navy will require 77,000 enlisted men. less apparatus and operators on ships and requiring wireless apparatus and operators on sea or land to be licensed and to conform to requirements of the international treaty and American law designed to prevent the interference of wireless stations with one another. To carry out these laws and the treaty the Bureau has radio inspectors at the principal seaports and Great Lake ports to inspect wireless apparatus on ships before their departure and make sure that the main apparatus is efficient and that the auxiliary apparatus, employed if the main apparatus is put out of operation by accident at sea, is ready for use. In the last fiscal year these officers made 7,236 inspections of ships before leaving port. regulating American merchant ships and foreign merchant ships in American ports fill a volume of considerable size, popularly termed the Navigation Laws. These laws are designed partly to insure the safety of passengers and crews, partly to prevent the misuse of the American flag, to secure revenue and to prevent frauds on the revenue, to promote American shipbuilding, to secure comfortable quarters for steerage passengers, to prevent collisions, fire and other casualties, to secure efficient officers and sufficient crews, to furnish complete statistical records within limits, to regulate trade with foreign ports and be tween American ports, including those in Alaska, Hawaii and Porto Rico, and for many other purposes. Violations of these laws involve penalties of greater or less severity and from the beginning of Government it has been found necessary to lodge somewhere discretionary power to mitigate or remit such penalties when circumstances warranted that action, the full statutory penalties being imposed in flagrant and willful cases. This discretionary power is lodged in the Secretary of Commerce, and the preliminary investigation of such matters is made for him by the Bureau of Navigation, which ascertains all the facts and recommends a course of action to the Secretary. Last year 7,895 such cases were examined by the Bureau of Navigation. At seaports violations of law are reported by collectors of customs, radio inspectors, Coast Guard officers, inspectors specially designated to see to it that steamers, especially excursion steamers, do not leave port with more passengers than can be safely carried, and by steamboat-inspection officers. Each owner, master, officer or man charged with violation of law has an opportunity to offer his defense or excuse in writing, and the evidence is then weighed by the Bureau of Navigation and a recommendation made to the head of the department. tion for many parts of the country and motor boating became a national sport the navigation laws have come close to thousands of Americans who before were only remotely aware of their existence. There are about 250.000 motor boats on the waters of the United States. The Bureau of Navigation has two motor boats of its own ("Dixie" and "Tarragon") which are almost constantly engaged in securing compliance with the laws among vessels generally, but especially among motor boats. They cover the Atlantic coast from KM st port, Me., to Key West, Fla., visiting the intervening bays, harbors, sounds, and rivers during the seasons of greatest local activity, and have proved to be an efficient and economical means of securing strict compliance with the navigation laws. vising Inspector General, who is stationed at Washington, and under the Supervising Inspector General is the Deputy Inspector General. In addition to the clerical force at Washington there work directly under the supervision of the central office, two traveling inspectors, one located at New York, N. Y., and the other at San Francisco, Cal., whose business it is to re-examine vessels with a view to ascertaining whether the local inspectors have properly inspected the same, and also to follow up complaints that may be referred to them by the central office. A corps of assistant inspectors, detailed for duty at the steel mills for the purpose of testing plate to be used in construction of marine boilers, also works under the direct supervision of the central office. The United States, including Hawaii, Alaska and Porto Rico, is divided into ten supervising inspection districts, over each of which districts presides a supervising inspector. The Supervising Inspector General and the ten supervising inspectors above referred to constitute the Board of Supervising Inspectors, which meets in annual session the third Wednesday of January each year for the purpose of establishing all necessary regulations required to carry out in the most effective manner the laws that relate to the Steamboat Inspection Service. Each Supervising inspection district is divided into local inspection districts. Over each local inspection district a board of local inspectors, consisting of an inspector of hulls and an inspector of boilers, presides. In those districts where the pressure of work requires it, there are also stationed assistant inspectors, who work under the supervision of the board of local inspectors of the district. ACTIVITIES OF THE SERVICE The Service exists for the purpose of inspecting vessels, licensing officers and conducting investigations of disasters and violations of law. Once each year, steamers subject to inspection are required to have the hulls of the same thoroughly examined, and the inspectors must satisfy themselves that such vessels are of a structure suitable for the service in which they are to be employed, have suitable accommodations for passengers and crew, and are in a condition to warrant the belief that they may be used in navigation as steamers with safety to life, and the inspectors have to satisfy themselves that all the requirements of law in regard to fires, boats, pumps, hose, life preservers, floats, anchors, cables, and other things are faithfully complied with. Furthermore, all excursion and ferry steamers are required to be reinspected three times during the year for which certified or during the period of navigation. Local inspectors are also required to inspect the boilers and their appurtenances in all steam vessels before the same shall be used, and once at least in every year thereafter, are required to subject all boilers to hydrostatic pressure. They must assure themselves that the boilers are well made, of good and suitable material ; that the openings for the passage of wa- ter and steam, respectively, and all pipes and tubes exposed to heat, are of proper dimensions and free from obstructions ; that the spaces between and around the flues are sufficient; that flues, boilers, furnaces, safety valves, fusible plugs, lowwater indicators, feed-water apparatus, gauge cocks, steam gauges, water and steam pipes connecting boilers, means of prevention of sparks and flames from fire doors, low-water gauges, means of removing mud and sediment from boilers, and all other such machinery and appurtenances thereof, are of such construction, shape, condition, arrangement, and material that they may be safely employed in the service proposed without peril to life. Applicants for licenses from the Service obtain the same in all instances, except in the case of operators for motor boats, after due written examination before the local inspectors having jurisdiction, and in the case of deck officers, in addition to the written examination, they are examined as to color-sense and visual acuity. As a result of the Seamen's Act, the Service also certificates able seamen and lifeboat men. The boards of local inspectors have authority by statute to investigate disasters and violations of law, and when they are conducting such investigations they are proceeding in a quasi judicial manner, and by statute certain appeals are provided from the local inspectors to the supervising inspectors, and in certain instances, to the Supervising Inspector General. veloping the welfare of the wage earners of the United States, improving their working conditions, and advancing their opportunities for profitable employment. He has power under the law to act as mediator and to appoint commissioners of conciliation in labor disputes whenever in his judgment the interests of industrial peace may require it to be done. He has authority to direct the collecting and collating of full and complete statistics of the conditions of labor and the products and distribution of the products of the same and to call upon other departments of the Government for statistical data and results obtained by them and to collate, arrange, and publish such statistical information so obtained in such manner as to him may seem wise. His duties also comprise the gathering and publication of information regarding labor interests and labor controversies in this and other countries ; the supervision of the immigration of aliens, and the enforcement of the laws relating thereto, and to the exclusion of Chinese; the direction of the administration of the naturalization laws ; the direction of the work of investigating all matters pertaining to the welfare of children and child life and to cause to be published such results of these investigations as he may deem wise and appropriate. The law creating the Department of Labor provides that all duties performed and all power and authority possessed or exercised by the head of any executive department at the time of the passage of the said law, in and over any bureau, office, officer, board, branch, or division of the public service by said act transferred to the Department of Labor, or any business arising therefrom or pertaining thereto, or in relation to the duties performed by and authority conferred by law upon such bureau, officer, office, board, branch, or division of the public service, whether of an appellate or advisory character or otherwise, are vested in and exercised by the head of the said Department of Labor. The Secretary of Labor is also given authority and directed to investigate and report to Congress a plan of co-ordination of the activities, duties, and powers of the office of the Secretary of Labor with the activities, duties, and powers of the present bureaus, commissions, and departments, so far as they relate to labor and its conditions, in order to harmonize and unify such activities, duties, and powers, with a view to additional legislation to further define the duties and powers of the Department of Labor, and to make such special investigations and reports to the President or Congress as may be required by them or which he may deem necessary, and to report annually to Congress upon the work of the Department of Labor. The disbursing clerk is charged by the and accounting for Government requests Secretary of Labor with the duty of for^ transportation issued to officers of preparing all requisitions for the advance the department for official travel ; the of public funds from appropriations for audit and payment of all vouchers and the Department of Labor to disbursing accounts submitted from the various clerks and special disbursing agents offices, bureaus, and services of the decharged with the disbursement of public partment ; the general accounting of funds ; the keeping of appropriation the department ; and the accounting for lodgors relating to the advance and ex- all 'naturalization receipts received under penditure of all items of appropriations. the provisions of the act of June 29, The Chief of the Division of Publica- of the department and conducts the cortions and Supplies is charged by the respondence it entails. Under the direcSecretary of Lr.bor with the conduct of tion of the chief clerk he has pejsonal all business the department transacts supervision of all the work incident with the Government Printing Office; to the purchase and distribution of the general supervision of printing, in- supplies for the department proper and eluding the editing and preparation of for the services of the department outcopy, illustrating and binding, the dis- side of Washington and of the keeping tribution of publications, and the main- of detailed accounts of all expenditures tenance of mailing lists. All blank from the appropriation for contingent books and blank forms and the printed expenses of the department. He restationery of all kinds used by the bu- ceives, verifies, and preserves the semireaus and offices of the department in annual returns of property from the Washington and the various outside ser- offices and bureaus of the department vices of the department are in his cus- which are supplied from the contingent tody and are supplied by him. The ad- appropriation, and examines and reports vertising done by the department is in on the semi-annual property returns of his charge. He also keeps a record of all other bureaus and services of the all expenditures for the publishing work department. The division of Information, under the Bureau of Immigration, gathers from all available sources information concerning the resources, products, and physical characteristics of the States and Territories. This information is made available to admitted aliens and others seeking homes or places of settlement. Under the direction of the Secretary of Labor, the division also acts as a division for the distribution and employment of labor, and is the central oflBce of the eighteen distribution zones covering the entire United States. In this phase of its activities it co-operates with the Post Office Department, the Department of Agriculture, and the Department of the Interior. BUREAU OF NATURALIZATION The act approved March 4, 1913, creating the Department of Labor, provided a Bureau of Naturalization, and that the Commissioner of Naturalization, or, in his absence, the Deputy Commissioner of Naturalization, shall be the administrative officer in charge of the Bureau of Naturalization and of the administration of the naturalization laws under the immediate direction of the Secretary of Labor. Under the provisions of the act of June 29, 1906, naturalization jurisdiction was conferred upon approximately 3,500 United States and State courts. The duties of the Bureau of Naturalization are to supervise the work of these courts in naturalization matters, to conduct all correspondence relating to naturalization, and, through its field officers located in various cities of the United States, to investigate the qualifications of the candidates for citizenship and represent the Government at the hearings of petitions for naturalization. In the archives of the bureau are filed duplicates of all certificates of naturalization granted since September 26, 1906, as well as the preliminary papers of all candidates for citizenship filed since that date, averaging an annual receipt of approximately 450,000 naturalization papers. BUREAU OF LABOR STATISTICS The Bureau of Labor Statistics is charged with the duty of acquiring and diffusing among the people of the United States useful information on subjects connected with labor in the most general and comprehensive sense of that word, and especially upon its relations to capital, the hours of labor, the earnings of laboring men and women, and the means of promoting their material, social, intellectual, and moral prosperity. It is especially charged to investigate the causes of and facts relating to controversies and disputes between employers and employees as they may occur, and which may happen to interfere with the welfare of the people of the several States. It is also authorized, by act of March 2, 1895, to publish a bulletin on the condition of labor in this and other countries, condensations of State and foreign labor reports, facts as to conditions of employment, and such other facts as may be deemed of value to the industrial interests of the United States. This bulletin is issued in a number of series, each dealing with a single subject or closely related group of subjects, and the bulletin is published at irregular intervals as matter becomes available for publication. By the act to provide a government for the Territory of Hawaii, as amended, it is made the duty of the bureau to collect and present in quinquennial reports statistical details relating to all departments of labor in the Territory of Hawaii, especially those statistics which relate to the commercial, industrial, social, educational and sanitary condition of the laboring classes. The administration of the act of May 30, 1908, granting to certain employee's of the United States the right to receive from it compensation for injuries sustained in the course of their employment, is vested in the bureau by the act of March 4, 1913, creating the Department of Labor. The act establishing the bureau provides that it shall investigate and report upon all matters pertaining to the welfare of children and child life among all classes of our people, and shall especially investigate the questions of infant mortality, the birth rate, orphanage, Juvenile courts, desertion, dangerous oc- cupations, accidents and diseases of children, employment, and legislation affecting children in the several States and Territories. The bureau is also empowered to publish the results of these investigations in such manner and to such extent as may be prescribed by the Secretary of Labpr. was created by act of Congress in 1846, under the terms of the will of James Smithson, an Englishman, who, in 1826, bequeathed his fortune to the United States of America to found, at Washington, under the name of the "Smithsonian Institution," an establishment for come of the fund a building, known as the Smithsonian building, was erected on land given by the United States. The Institution is legally an establishment having as its members" the President of the United States, the Vice-President, the Chief Justice and the President's Cabinet. It is governed by a Board of Regents consisting of the Vice-President, the Chief Justice, three members of the United States Senate, three members of the House of Representatives and six citizens of the United States, appointed by joint resolution of Congress. It is under the immediate supervision of the secretary of the Smithsonian Institution, who is the executive officer and the director of all of the Institution's activities. For the increase of knowledge the Institution aids investigators by making grants for research and exploration, supplying books, apparatus, laboratory accommodations, etc. It occasionally provides for lectures, which are published. It has initiated numerous scientific projects of national importance, some of Vhich have resulted in the creation of independent Government bureaus. It advises the Government in many tional aspect. For the diffusion of knowledge the Institution issues three regular series of publications : Annual Reports, Smithsonian Contributions to Knowledge and the Smithsonian Miscellaneous Collections. All these publications are distributed gratuitously to important libraries The Institution, in co-operation with the Library of Congress, maintains a scientific library which numbers 260,000 volumes, consisting mainly of the transactions of learned societies and scientific periodicals. ministrative charge of several branches which grew out of its early activities and which are supported by Congressional appropriations. These are the National Museum, including the National Gallery of Art ; the International Exchange Service ; the Bureau of American Ethnology ; the National Zoological Park; the Astrophysical Observatory, and the Regional Bureau for the International Catalogue of Scientific Literature. gress of 1846 founding the Smithsonian Institution, and under its direction, the United States National Museum is the designated depository for the national col- tory, being also charged with their classified arrangement and their use in advancing knowledge and promoting education. Starting with accommodations in the Smith- building, which it still largely occupies, two extensive structures have since been erected especially for its purposes, one completed in 1881, the other in 1911. Located on the Mall, between Ninth and Twelfth Streets, these three buildings furnish the museum with about 650,000 square feet or nearly 15 acres of floor space, somewhat more than half of which is devoted to the public exhibitions. torium. The natural history collections, including, besides zoology and botany, geology, paleontology, ethnology, archeology and physical anthropology, represent the greatest and most important growth of the museum. The first notable acquisition consisted of the rich and varied results of the cruise of the U. S. Exploring Expedition in the South HALL OF AMEEICAN HISTORY, OLDEE BUILDING, U. S. NATIONAL MUSEUM The latest building, four stories high, of white granite, with a main frontage of 561 feet and a depth of 364i/2 feet, and costing $3.500.000, is architecturally one of the most prominent among the Government edifices in Washington. Specifically designed to meet the requirements of natural history, and with its two main floors and part of another composed of large exhibition halls, it also contains exceptionally extensive and well-appointed laboratories Seas and other waters during the four years from 1838 to 1842. Then, for a long period, the bulk of the accessions came from numerous special explorations, principally by the Government, in the western part of the United States, and to some extent in other near and far regions; and these were followed by the regularly organized Government surveys and' investigations, still in progress. Through thousands of other sources material from every quarter of the globe has also been acquired, and this constant flow of specimens has advanced the National Museum in its natural history departments to the highest rank among the museums of the world. Its collections are, naturally, most complete for North America, and, besides having served as the basis for extended and important researches for over two thirds of a century, they have been liberally utilized in the interest of general education, with methods of public installation developed to a remarkable stage of perfection. of periods, the most conspicuous feature being a large and varied series of Washington relics. One hall is devoted to costumes and another to coins, medals and postal tokens. The industrial art collections are of great importance both historically and suggestively, and while inadequate facilities have somewhat retarded their development, they already form the basis of a -department of the utmost practical significance. Among the subjects even sonian buildings are assigned to American history and the industrial arts, except that the upper main story of the latter structure is occupied by the division of plants, or National Herbarium. The exhibition collections of history, which fill four halls, are especially rich in mementoes of prominent persons and laces, embroideries, woods, medicines, foods and the various miscellaneous uses to which animal and vegetable products are put ; the processes of mining and of dealing with mineral products ; land, water and air transportation; fire arms and other weapons, weights and measures ; electrical and other inventions, including the telegraph, tele- The National Gallery of Art or department of the fine arts acquired in 1849 a notable series of engravings of the old masters and many works on art which had been assembled by George P. Marsh. Occasional additions were received in subsequent years, but it was not until the bequest of Harriet Lane Johnston in 1906 that the gallery took form. This collection of seventeen paintings, besides other objects, includes a Luini and several excellent English and Dutch portraits. In the same year Mr. Charles L. Freer, of Detroit, Mich., presented his notable collection of American and Oriental art, to which he has constantly added until its size has been more than doubled. It now consists of some 5,346 articles, of which over 1,000 are paintings, pastels, drawings, engravings, lithographs, etc., by nine American artists, headed by Whistler; while the Oriental objects, exceeding 4,300 in number, some of which date back several centuries B. C., include paintings, pottery, bronzes, sculptures, jades, glass, etc., mainly from China, Japan, Corea, Persia, India, Mesopotamia and Egypt, constituting a collection of exceptional value, unrivaled in Ihe importance of the material it furnishes for research into the art of the Far East. To Mr. William T. Evans, of New York, the gallery is indebted for a selection of 151 paintings in illustration of the work of contemporary American artists, 106 of whom are represented, and also for numerous examples of the best American wood engraving. There have also been many individual contributions to the gallery, and, in default of other accommodations, its possessions are provisionally installed in the natural history building, except the Freer collection, for which a special building has been designed and will immediately be erected at the expense of Mr. Freer. THE INTERNATIONAL EXCHANGE SERVICE The International Exchange Service— a branch of the United States Government carried on under the direction of the Smithsonian Institution— serves as an intermediary for the exchange of scientific and literary publications between establishments and individuals in the United States and those in foreign countries. This phase of its work was begun soon after the Institution was founded in 1846. Later, in 1867, an exchange of official documents between governments was established, and Congress, by act of March 2 of that year, provided for this purpose a certain number of copies of all parliamentary acts and of all publications printed by order of any department or bureau of the Government, which are forwarded through the Exchange Service to various foreign countries. ogy was established by Congress in 1879, at the instance of the late Major J. W. Powell, for the purpose of conducting ethnologic researches among the American Indians, but subsequently its investigations were extended to include Hawaii. Although devoted chiefly to the aborigines in the United States, researches by the bureau have been conducted in lesser degree in Canada, Mexico, Central America, South America and the West Indies. In these investigations ethnology has been taken in its broadest sense to include all the activities of the Indian race, as well as their archeology and history. The results of the bureau's studies to the present time are erabodied in thirty-three annual reports and sixty-three bulletins published or in press, as well as a number of miscellaneous publications. The bureau maintains a corps of nine ethnologists, possesses an eth- nologic reference library of about 21,500 volumes and 13,500 pamphlets, many thousand photographic negatives of Indian portraits and other subjects, and a large collection of original manuscripts, pertaining chiefly to Indian linguistics. NATIONAL ZOOLOGICAL PARK The National Zoological Park, established by act of Congress in 1890, "for the instruction and recreation of the people," and placed under the direction of the Smithsonian Institution, maintains a collection of living animals which is exhibited free to the public. The park occupies 169 acres in the val- ley of Rock Creek, about three miles ways. northwest of the White House. The collection comprises (June 30, 1916) about 1,400 specimens. The number of visitors during 1915 was over 1,000,000. The park co-operates with the United States National Museum, the Department of Agriculture, the United States Hygienic Laboratory, and private investigators, in various in 1890 and supported by small annual appropriations by Congress, is engaged in exact measurements of the intensity of the sun's radiation. Principal results : Map of Fraunhofer lines of infra-red solar spectrum to wave-length 53000 Angstroms. Determination of the mean intensity of solar radiation outside the earth's atmosphere, 1.93 calories per square centimeter per minute. Discovery of the variability of the sun's radiation through a range of about 5 per cent attending the sun spot cycle, and also of an irregular variability, sometimes reaching 10 per cent in short intervals of a few days or weeks. Principal observing station on Mount Wilson, California. Expeditions to North Carolina, Sumatra, Flint Island for total solar eclipse work, and to Mount Whitney, Cal. (14,500 feet) and Bassour, Algeria, for solar Scientific Literature publishes an annual classified index to the literature of science. The organization consists of a central bureau in London and thirty-three regional bu- reaus established in, and supported by, the principal countries of the world. That for the United States is supported by an annual appropriation from Congress, administered by the Smithsonian Institution. done in private offices. This plan became expensive and unsatisfactory, and in 1861 Congress authorized the purchase of the printing plant then owned by Cornelius Wendall, located on a portion of the site now occupied by what is known as the "old building." This office at the time of purchase employed 300 persons, and the Government paid approximately $135,000 for the building and equipment. Subse- meet the demands for work. The development of printing and binding for the public is typical of the industrial and commercial growth of the republic, and emphasizes the spirit of inquiry and investigation that characterizes the American people — a spirit that is causing an almost fabulous volume of printing on subjects of general, special, or peculiar interest to our citizens. ters having become imperative, Congress authorized the construction of the present building on ground adjoining the old offices. This building is of magnificent proportions, and is a landmark in the Capital City, and an enduring monument to the art of typography and the part it plays in our Government. It contains 7 floors, with basement and loft, with floor space of 372,350 square feet, and cost approximately $2,410,000. The old building is used principally for storage, and combined floor area of entire plant is 13% acres. The office is as nearly fireproof as any building can be made, and numerous wide staircases are distributed in such a way as to facilitate the egress of employees in case of fire or panic. The most upto-date sanitary conditions prevail, an emergency hospital is provided for the use of employees, and a "rest room" is available for use of women employees who may become exhausted during working hours. There are about 4,000 persons employed, and the entire plant is under the direct management of the Public Printer, who is appointed by the President at an annual salary of $5,500. The general layout is as follows: Job Composing Room — 92 employees, with up-to-date equipment ; this section handles 30,000 jobs in a year. Linotype Composing Section — 245 employees, with 81 linotype machines and first class equipment; about 1 year on the linotype machines. Monotype Composing Section — 435 employees, with 165 keyboards and 126 casters ; about 1 billion 300 million ems of type are set in one year on the monotype machines. Hand making up and imposing. Proof Room — 270 employees, engaged in editing, preparing, reading and revising. Electrotype and Stereotype Foundry — 130 employees, with up-todate equipment, producing over 13,000,000 square inches of plated matter in a year. Press Room — 443 employees, with 145 modern presses ; all rollers and about one-third of necessary ink are made on premises. Bindery — 950 employees, with complete machine equipment for all kinds of pamphlet and bound work. A number of smaller divisions cards, money order books, etc. Branch offices are located in the State, War and Navy building and in the Congressional Library, and handle emergency work for these branches of the Government. The buildings contain 16 elevators, besides several lifts for handling forms of type from pressroom- or foundry. Eight automobile trucks, with capacity ranging from 1,000 to 8,000 pounds each, together with a number of side-car motorcycles, deliver all work produced in tjie Government Printing Office. Pneumatic tubes furnish rapid communication between various divisions. A plate vault for the storage and safekeeping of electrotype and stereotype plates is located in the basement of the new building, occupying 10,000 square feet of floor space ; old plates are constantly being destroyed and the metal used over, and new plates added ; about 1,200,000 plates, weighing approximately 7,000,000 pounds, are constantly on hand. sists of four electric generator? totaling 2,500 kilowatts, two air compressors with, capacity of 3,000 cubic feet of free air per minute, one 2,000,000 gallon pumping engine, and one refrigerating plant for circulating drinking water and making ice. The boiler room equipment consists of eight boilers, six of which are Scotch marine type, hand fired, totaling 1,800 horse-power, and two are water tube boilers with automatic stokers, totaling 1,000 horsepower ; a total of 2,800 horse-power. The total value of all machine equipment is approximately $2,500,000. The upkeep of building and equipment is under the direction of a superintendent of buildings, and this work is handled by an electrical division with 71 employees, a machinists' division with 32 employees, a carpenter division with 27 employees and a building division with 36 employees. The materials used yearly are as follows: Paper stock, 32,000,000 pounds; ink, 65,000 pounds; leather stock, 300,000 square feet; gold and aluminium, 30,000,000 square inches ; sewing thread, 32,000,000 yards; cloth for binding, 250,000 yards; wire for stitching, 6,500,000 feet; glue, 225,000 pounds; paste, 34,000 gallons; card containers, 3,000,000; metals, 200,000 pounds; keyboard paper, 10,200,000 feet; coal, 12,500 tons ; soap, 40,000 pounds. The Government Printing Office is the largest office in the world, but printing and binding is increasing so rapidly that it is only by extensive systematizing of production methods can Government needs be met. The vast increase in work is shown by fact that blanks, schedules, postal cards, money order forms, envelopes and similar work printed in fiscal year 1915 totaled about 3 billion copies, as compared with about 131 millions in 1880. Book work increased proportionately and about 1,700,000 type pages are set in one year. The output of postal cards is approximately 4,000,000 a day. About 120,000,000 money order forms are printed each year and delivered in books of from 50 to 200 each. Some of the principal items of production in a year are : Copies on job work, postal cards and money orders, 3,000,000,000; blank books, 1,130,000; newspapers and miscellaneous documents bound, 100,000 ; pamphlets and books printed, 100,000,000. In addition, the Daily Congressional Record is printed each night during session of Congress, varying in size from 8 to 225 quarto pages ; the copy comes in late at night — some of it as late as 2 A. M. ; type must be set, plates made, 34,000 copies printed, folded, gathered, wire-stitched and addressed in time to catch early morning mail. About 30 million copies of speeches are on paper, and delivery made to the Capitol, one half mile distant, in from 15 to 20 minutes after copy is received. The bound Congressional Record, covering proceedings of the 63d Congress, 2d Session, made 19 volumes ; 6,130 copies were printed and bound on each volume, making a total of 116,470 volumes. The total annual expense of the office is about $6,500,000, and this amount is divided and allotted between Congress, the departments and the various bureaus of the Government, in accordance with their necessity for printing, each being allowed printing and binding only to the amount of their allotment. Ex- Congress and paid for by them. Approximately 25,000 bills and resolutions of Congress are printed during a session, varying in size from 2 to 200 pages, with from 200 to 800 copies on each. During the closing hours of a session of Congress the pressure for hurried work is tremendous and there have been times 1 copy printed on parchment and 3 isting law requires this printing and binding to be done at cost, and charges are based upon a fixed scale of prices, regulated by a modern cost system, and rendered for each piece of work produced. Employees work eight hours a day, receive a compensation comparing favorably with union wages paid throughout the country, and are allowed thirty days' vacation with pay each year. Some divisions of the office run night forces throughout the year and over day rates in pay. The Division of Public Documents is a central distributing agency for Government publications and receives, by law, copies of all . public documents printed in the Government Printing Office. A specified number of these documents are distributed to certain designated depository libraries throughout the country, and other copies are sold at cost to the public, no more than one copy to any one person. Forty million documents are sent out by this division in a year, and in order to facilitate mailing a 30-inch belt conveyor, operating through a tunnel 7 feet high, 8 feet wide and 455 feet long, connects the Government Printing Office with the mailing tables of the city post office. Copies of Government publications can be secured by writing the Superintendent of Documents, Government Printing Office, Washington, D, C. COUNCIL OF NATIONAL DEFENSE The Council of National Defense was created by the act of June 3, 1916. Its membership consists of the Secretaries of War, Navy, Interior, Agriculture, Commerce and Labor, and a civilian advisory commission of seven members nominated by the Council and appointed by the President. The Advisory Commission is comi)osed of Daniel Willard, president of the Baltimore & Ohio Railroad, chairman ; Samuel Gompers, president of the American Federation of Labor; Dr. Franklin H. Martin, of Chicago ; Howard E. Coffin, of Detroit; Bernard Baruch, of New York; Dr. Hollis Goudfrey, of Philadelphia, and Julius Rosenwald, of Chicago. All the members, as such, serve without compensation, but are allowed actual expenses of travel and subsistence when attending meetings of the Council", or engaged in investigations pertaining to its activities. The duties of the Council are to supervise and direct investigations and make recommendations to the President and the heads of executive departments as to the location of railroads, with reference to the frontiers of the United States, so as to render possible expeditious concentration of troops and supplies to points of defense ; the co-ordination of military, industrial, and commercial purposes in the location of extensive highways and branch lines of railroads ; the utilization of waterways ; the mobilization of military and naval resources for defense ; the increase of domestic production of articles and materials essential to the support of armies and of the people during the interruption of foreign commerce; the development of seagoing transportation ; data as to amounts, location, method and means of production, and availability of military supplies; the giving of information to producers and manufacturers as to the class of supplies needed by military and other services of the Government, and the creation of relations which will render possible in time of need the immediate concentration and utilization of the resources of the nation. It establishes the policy for the Government departments as regards national defense. The actual work will be done by sub-committee. Its first meeting was held Dec. 6, 1916. water, when both are used under common control, management, or arrangement for a continuous carriage or shipment, including express, sleeping and parlor car companies, telephone, cable, telegraph and wireless companies, and all pipe lines, from one State, Territory, or District of the United States to any other State, Territory, or District of the United States, or to any foreign country. It has jurisdiction to inquire into and report on the reasonableness of rates ; undue or unreasonable preferences or advantages in transportation rates or facilities; to prescribe the publicity to be given to joint tariffs; the power to call for reports, to require the attendance of witnesses and the production of books and papers, to hear complaints of the violation of the act made against any carrier, and to determine what reparation shall be made to the party wronged. By the act of June 18, 1910, the jurisdiction of the commission was increased as to through rates, and joint rates, freight classification, switch connections, long and short hauls, filing or rejection of freight schedules, investigations on own motion, determining reasonable rates, suspension of proposed rates, and other matters. The act of March 2, 1893, known as the "safety appliance act," provides that railroad cars used in interstate commerce must be equipped with automatic couplers, and drawbars of a standard height for freight cars, and have grabirons or handholds in the ends and sides of each car; and that locomotive engines shall be equipped with a power driving-wheel brake and appliances for operating the train-brake system. Other acts have delegated further powers and duties to the commission, such as regulating the safe transportation of explosives by common carriers ; compelling railroad companies to equip locomotives and tenders with safe appurtenances; the investigation of railroad accidents ; compelling railroads to equip cars with sill steps, hand brakes, ladders, running boards, and roof handholds, and designating the number, dimensions, location and manner of application of appliances ; and making common carriers liable for all damage to property caused by them, and forbids, with certain exceptions, limitations of liability. The commission has been directed to investigate, ascertain, and report the value of property owned or used by every common carrier. The commission is now composed of seven members. It appoints a secretary, and such attorneys, examiners, special agents, and clerks as are necessary in the proper performance of its duties. CIVIL SERVICE COMMISSION The purpose of the civil service act, as declared in its title, is "to regulate and improve the civil service of the United States." It provides for the appointment of three commissioners, not more than two of whom shall be adherents of the same political party, and makes it the duty of the commission to aid the President, as he may request, in preparing suitable rules for carrying the act into effect. The act requires that the rules shall provide, among other things, for open competitive examinations for test- ing the fitness of applicants for the classified service, the making of appointments from among those passing with highest grades, an apportionment of appointments in the departments at Washington among the States and Territories, a period of probation before absolute appointment, and the. prohibition of the use of official authority to coerce the political action of any person or body. The act also provides for investigations touching the enforcement of the rules, and forbids, under penalty of fine or imprisonment, or FEDERAL RESERVE BOARD Generally speaking, the .functions of the Federal Reserve Board are to exercise a broad supervision over the affairs and conduct of twelve Federal reserve banks established in accordance with the terms of the Federal reserve act in different parts of the country and invested with authority to discount paper, issue Federal reserve notes, and perform the various banking functions described in the act itself. The board has full power to appoint its own staff of employees and officers and to regulate the conditions of their employment. Its support is derived from the several reserve banks from assessments levied by it half yearly pro rata. The board is responsible to Congress and reports annually to that body. Certain functions in connection with the national banking system are also assigned to it under the legislation, although the Comptroller of the Currency, who is a member of the board, exercises the same general administrative and supervisory authority over the national banks that has been in his hands in the past. The Federal Trade Commission was organized March 16, 1915. It consists of five Commissioners, appointed by the President. Their term of office is seven years, and not more than three of them shall be of the same political party. The work of the Commission falls within three main divisions. First, it is charged with the duty of enforcing the law against unfair methods of competition. It receives informal complaints of such methods employed in interstate commerce. If upon examination there is, in the judgment of the Commission, reason to believe that such unfair methods are being used it proceeds to have them corrected, either by informal negotiations with the parties complained against or, in case this fails, by filing its own formal complaint and conducting hearings in the case. If the practices complained of are found actually to exist the Commission issues its order directing those indulging in them to cease and desist. The Commission has considered and disposed of many cases and in most instances the practices complained of have of formal complaints. Second, it makes, either on its own initiative, if deemed in the public interest, or by direction of either House of Congress, special investigations of particular industries for the purpose of ascertaining all the facts relative thereto, with the view of correcting abuses if any are found to exist. It has concluded, or is now conducting, investigations of this kind with respect to the fertilizer, petroleum, beet sugar, coal and print paper industries, and others. It has also investigated conditions in the foreign trade of the United States and the tariff laws and regulations of several South American countries. Third, it offers its advice and assistance to business men along lines that will be helpful in bringing about greater efficiency. In this connection it has prepared systems of cost accounting that are adapted to the needs of manufacturers and merchants. In addition to this its expert accountants are available to associations of business men for the purpose of conferring with them and offering advice with respect to their accounting methods. Merchants and manufacturers can obtain copies of bulletins containing the accounting systems upon application to the Commission at Washington, D. C. enlarged. The Board passes on all unsettled questions concerning geographic names which arise in the departments, as well as determining, changing and fixing place names within the United States and its insular possessions, and all names hereafter suggested by any officer of the Government shall be referred to the board before publication. The decisions of the board are to be accepted by all departments of the Government as standard authority. Advisory powers were granted the board concerning the preparation of maps compiled, or to be compiled, in the various offices and bureaus of the Government, with a special view to the avoidance of unnecessary duplications of work; and for the unification and improvement of the scales of maps, of the symbols and conventions used upon them, and of the methods of representing relief. All projects of importance are now submitted to this board for advice before being undertaken. COMMISSION OF FINE ARTS The duties of the Commission of Fine Arts consist of giving general advice upon the location of statues, fountains and monuments in the public squares, streets and parks in the District of Columbia ; upon the selection of models for statues, fountains and monuments erected under the authority of the United States ; and the method of selection of the artists for their execution ; upon the plans and designs for public structures and parks in the District of Columbia; and upon all questions involving matters of art with which the Federal Government is concerned. The commission advises upon general questions of art whenever requested to do so by the President or a committee of Congress. ARLINGTON MEMORIAL AMPHITHEATER COMMISSION Created by public buildings act of March 4, 1913, to direct the construction of a memorial amphitheater and chapel in Arlington National Cemetery, Virginia, at a cost of $750,000. The building will consist of an elliptical structure inclosing an open-air amphitheater with seating capacity for about 5,000 persons. The exterior of the building will be in the form of a colonnade of white Vermont marble with entrances at the ends of the principal axes. The front entrance will be on the east, and this section will contain on the first floor a recep- tion hall and stage of the auditorium, a museum room on the second floor and a chapel in the basement. Tlu entrance will be on the west side. Secretary of War, chairman ; the Secretary of the Navy, the superintendent of the United States Capitol Building and Grounds and representatives of the Grand Army of the Republic, Confederate Veterans and United Spanish War Veterans. ALASKAN ENGINEERING COMMISSION The Alaskan Engineering Commission was created under the act of March 12. 1914, which empowered, authorized, and directed the President to locate, construct, operate, or lease a railroad, or railroads, to connect the interior of Alaska with one or more of the open navigable ports on the coast. Authority was also granted to purchase existing railroads, to construct, maintain, and operate telegraph and telephone lines, and to make reservations of public lands in Alaska necessary for the purposes of the railroad. For the execution of this work a commission of three engineers was appointed by the President to make the necessary surveys. They were directed to report to the Secretary of the Interior, under whom the President has placed the general administration of the work. The National Advisory Committee for Aeronautics was appointed by the President, pursuant to act of Congress approved March 3, 1915. Its membership consists of two officers of the Army, two officers of the Navy, a representative each of the Smithsonian Institution, the United States Weather Bureau, and the United States Bureau of Standards, together with one member from the Treasury Department and four professors from various universities who are acquainted with the needs of aeronautical science, or skilled in aeronautical engineering or its allied sciences. All the members, as such, serve without compensation. The duties of the committee, as provided by Congress, are to supervise and direct the scieatiflc study of the problems of flight, with a view to their practical solution, and to determine the problems which should be experimentally attacked, and to discuss their solution and their application to practical questions. AND CONCILIATION The purpose for which the Board of Mediation and Conciliation was established is to settle by mediation, conciliation, and arbitration controversies concerning wages, hours of labor, or conditions of employment that may arise between common carriers engaged In interstate transportation and their employees engaged in train operation or train service. The board is an Independent office, not connected with any department. GENERAL SUPPLY COMMITTEE It is the duty of the General Supply Committee to make an annual schedule of required miscellaneous supplies for the use of each of the executive departments and other Government establishments in Washington, to standardize such supplies, eliminating all unnecessary grades and varieties, and to solicit bids based upon formulas and specifications. It is composed of one officer from each of the executive departments, designated by the head thereof. BOARD OF INDIAN COMMISSIONERS The Board of Indian Commissioners, created in 1869, is a body of unpaid citizens, appointed by the President, who maintain an office in Washington, for the expenses of which and of travel Congress appropriates. The board Is not a bureau or division of any department, but is purposely kept reasonably Independent and afforded opportunities for investigation in order that it may freely express an intelligent and impartial opinion concerning Indian legislation and administration. Its legal duties are to visit and inspect branches of the Indian Service, to co-operate with the Commissioner of Indian Affairs In the purchase and inspection of Indian supplies, and to report to the Secretary of the Interior, to whom and to the President the board acts in an advisory capacity, with respect to plans for civilizing or dealing with the Indians. COMMISSION The International Joint Commission was created by treaty with Great Britain, and has jurisdiction over all cases involving the use or obstruction or diversion of waters forming the international boundary or crossing the boundary between the United States and Canada, and questions or matters of difference Involving the rights, obligations, or interests of the United States or of the Dominion of Canada. RIO GRANDE This commission was authorized by the protocol of May 6, 1896, between Mexico and the United States, and their treaty of 1848, authorizing the appointment of "commissioners" to settle "any disagreement" or "differences" between the two countries. It is commonly called "Commission for the Equitable Distribution of the Waters of the Rio Grande" — the boundary for about 1,300 miles between these two nations. The International (Canadian) Boundary Commissions were authorized by conventions or treaties between the United States and Great Britain, as follows : 1. January 24, 1906. For defining and marking the boundary between Alaska and British Columbia. Length, 862 miles. 2. April 21, 1906. For denning and marking the boundary between Alaska and Canada, along the 141st meridian. Length, 625 miles. 3. For defining and marking the boundary between the United States and Canada from the Atlantic Ocean to the Pacific Ocean, with the exception of the Great Lakes and the St. Lawrence River. Length, 2,647 miles. UNITED STATES BUREAU OF EFFICIENCY The duties of the Bureau of Efficiency are to establish and maintain a system of efficiency ratings for the executive departments in the District of Columbia ; to investigate the needs of the several executive departments and independent establishments with respect to personnel, and to investigate duplication of statistical work and methods of business in the various branches of the Government service. ounded upon the Constitution of the United States or any law of Congress, except for pensions, or upon any regulations of an executive department, or upon any contract, express or implied, with the Government of the United States, or for damages, liquidated, or unliquidated, in cases not sounding in tort, in respect of which claims the party would be entitled to redress against the United States, either in a court of law, equity, or admiralty, if the United States were suable, except claims growing out of the late Civil War and commonly known as war claims," and certain rejected claims. The court is also vested with the jurisdiction of certain Indian depredation claims. The Federal Workmen's Compensation Commission is charged with the administration of the Federal Workmen's Compensation Law. The law provides for the payment of 35 per cent of wages during widowhood to the widow of any workman employed by the Government and killed in the discharge of duty, and grants to a workman during period of total disability a monthly payment of two-thirds of his wages and a less amount in the case of partial disability. Provision is also made for payment to dependent's, other than the widow, in case of death of a workman. Park, in Washington, stands one of the most beautiful structures ever erected in the Western Hemisphere, namely, the building of the Pan-American Union. The structure and grounds represent an investment of $1,100,000, of which the American republics contributed $250,000 and Dr. Andrew Carnegie $850,000. The architecture is an appropriate combination of the classical and Spanish renaissance. A lofty vestibule opens into a typical Latin- American "patio," or courtyard, in the center of which is a beautiful fountain, while gorgeous parrots squawk around and tropical monkeys disport themselves in cages. Plants and flowers of the rarest flora of tropical America are found everywhere, while under* the cornice are the coats-of-arms of the American republics and the names of men prominent in their history. The glass roof above is operated by electricity and can be closed at a moment's notice. In the rear of the patio is a wide corridor, now used for exhibits of Latin-American large reading and reference room. The second floor is approached by two grand stairways and contains a broad corridor, or foyer, in which are suspended the national flags of the American republics. This foyer opens upon the "Hall of the Americas," a large salon 100 feet in length and 70 feet in width. On this floor will also be found the Governing Board room and offices. In the rear of the main structure is a beautiful sunken garden, with a pool forming the central feature, and the building of the Pan-American Annex forms the background. The tile effects are marvelous. It may well be asked what is the meaning of this magnificent building? What is its history, organization and purpose? merly known as the International Bureau of the American Republics) was established in the year 1890 in accordance with the resolutions passed at the first Pan-American conference, held at Washington in 1889-90, and presided over by Mr. Elaine, then United States Secretary of State. It was indorsed and continued by resolutions of the second conference at Mexico in 1901; the third, at Rio de Janeiro, in 1906, and the fourth, at Buenos Aires, in 1910. Its reorganization under the present administration dates practi- cally from January, 1907, following the third conference, which was attended by Elihu Root, then Secretary of State. international organization and office maintained by the twenty-one American republics, as follows : Argentina, Bolivia, Brazil, Chile, Colombia, Costa Rica, Cuba, Dominican Republic, Ecuador, Guatemala, Haiti, Honduras, Mexico, Nicaragua, Panama, Paraguay, Peru, Salvador, United States, Uruguay and Venezuela. It is devoted to the development and advancement of commerce, friendly intercourse and good understanding among these countries. It is supported by quotas contributed by each country, based upon the population. Its affairs are administered by a director general and assistant director, elected by and responsible to a Governing Board, which is composed of the Secretary of State of the United States and the diplomatic representatives in Washington of the other American governments. These two executive officers are assisted by a staff of internattonal experts, statisticians, commercial specialists, editors, translators, compilers, librarians, clerks and stenographers. The Governing • Board holds regular meetings to consider the work of the Pan-American Union and to act upon the reports and recommendations of the director general. This board in turn selects a supervising committee which considers matters not requiring the attention of the entire board. Appointments to the staff are made by the director general and the supervisory committee only after rigid competitive examination of applicants. Although, being an international institution, the PanAmerican Union is not under the rules of the United States Civil Service, its regulations covering examinations and additions to its staff are even more strict than those of the Civil Service and usually require an accurate and fluent knowledge of Spanish or Portuguese. Special pamphlets on the twenty Latin-American republics, with specific information as to their form of government, industries, etc., have been issued and may be obtained by addressing the Director - General, Pan-American Union, Washington, D. C.	219,726	common-pile/pre_1929_books_filtered	ourcountryitsres00hopkiala	public_library	public_library_1929_dolma-0008.json.gz:667	https://archive.org/download/ourcountryitsres00hopkiala/ourcountryitsres00hopkiala_djvu.txt
oXz2r0J5TzOOGnnN	An essay on the constitutional power of Great-Britain over the colonies in America with the resolves of the Committee for the province of Pennsylvania, and their instructions to their representatives in assembly.	The Instituta haa attampted to obtain the best original copy available for filming. Features of this copy which may be bibliographically unique, which may alter any of the images in the reproduction, or which may significantly change the usual method of filming, are checked below. distortion le long de la marge int6rieure Blank leaves added during restoration may appear within the text. Whenever possible, these have been omitted from filming/ II se peut que certaines pages blanches ajouttes lors d'une restauration apparaissent dans le texte, mais, lorsque cela dtait possible, ces pages n'ont pas M filmtes. Commentaires suppl6mentaires: L'institut a microfilm* le meilleur exemplaire qu'il lui a it* possible de se procurer. 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Les diagrammes sulvants illustrent la mAthode. John Dickinson, Doflor William Smith, Joseph Read, John Kidp, Ei.isha Price, William Atlk2, James i>MiTH, Jamis Wilson, Daniel Broadheap, John Okei.y, aud William Scull, are appointed to prepare and bring in a draught of inilrudions. Monday, July 18. * The conunittee appointed to bring in inftruftions, reported, that they had made a draught, which they laid upon the table, ' , Tue/Jay, July 19, Upon a motion made and feconded, agreed that the draught of inllrudtions brought in by the committee, and which were read, be re-committed to the fame committee. * The committees of the counties having bcch invited, by the committee tor the city and county of Philadelphia, to meet them at Philadelphia on the ijth ot July ; this committee thought it their duty, to make Tome preparation in the bufinels, that was te be laid before the provincial com'mittee by them. On the 4th of July they appointed a committee for this purpofc ; and this meafure enabled thofe appointed by the provincial committee to briu\|f in a draught fo foon. Tiur/Hay^ July 1 1 . The inllruAinns were figned by the chairman.— I'he committee in a body, waited on the AflJembly then fitting, and prefented the fame. It having been moved, that the eflay of the inftruflions firft propoled to be tiven to the honourable Affembly of Penn/yl'vania^ by the provincial committee aU'embled at Philaaeiphia i\ic 1 8th inftant might be abridged, leaving out the argumentative part, fo as to be more pioptr for inlliudions, the fame was agretd to ; but rtfoked at the fame lime, that the whole work ought to be publilhed, as highly delcrving the perulal and feriou.* confideration of every friend of liberty within thefe colonics. ^ Agretd unanimoujly^ That the thanks § of this committee b^ given from the chair to John Dickinson, Efq; for the great aflillance they have deiived from the laud&ble application of his eminent abilities to the fervicc of his country in the above performance, , , ,,., § Mr. Dickinson being abfent this day, on account of the funeral of a relation, the next diiy the chairman, in a very obliging maimer, delivered to him from the chuir the thankt of the committee ; to which he replied : '• Mr. Chairman, " I heartily thank this rcfpetaablc AflTcmbly for the honour they have confened upon me, but want words to exprcfs the fenfe I feel ot thtii kiudnefs. The mere accidents of meeting with particular books, and converting with particular men, led sne into the train of fcntiments, which the committee are pleafed to think juft ; and others, with the like opportunities of information would much bettei have defervcd to receive the thanks, they DOW gcneroufly give. I coniider the approbation of this company as an evidence, that they entertain a favourable opinion of my good intentions, and as an encouragement for all to apply themftlvcs, in thefe unhappy times, to the fervice of the public, fince even fmall endeavours to promote that fervicc, can find a very valuable reward. I will t\|;y, during the remainder ©f my life, to remember my duty to our common country, and, it it be pofljble, to render myfelf worthy of the honour tot which I now ftand fo deeply indebted. to form fome kind of a Iketch, however imperfeft it might be, of all the grievances of the colonies, and of courfe of their conflitutional rights. '"' Such an attempt, tho' very rude, might be improved by better hands; and it feemed abfolutely neceflaty, no longer to confine ourfelves to occafional complaints and partial remedies, but, if poffible, to attain fomc degree of certainty concerning our lives, liberties and properties. ;,^,,. ~ flifit ' ■ ' It was perceived, that if the indructions (hould be formed on this plan, they would comprehend m.any and ve- ry important pofitions, which it would be proper to introduce, by prcvioully alhgning die rcalbns, on which they were founded. Oiherwifc, the pofi* tions might not appear to the committee to be juft. From this confideration it became necelTary, to render the inftruflions long and argumentative ; and whoever candidly reflefls on the importance of the occafion, will think fuch a method very juftifiable. The draught of inflrufiions being brought into the provincial committee and read, and no objection being made to any of the principles aflerted in them, it was not thought neceffary, that the argumentative part (hould continue any longer in them. The committee, that brought in the draught, therefore moved, that this part of the infiru61ions might be feparated from the reft. Whereupon the draught was re committed, for this purpofe, to the committee, that Several additions have been made to the other part, now called ' An Effay," &c. fincc the vote for publilhing. The additions are diftinguifhed by crotchets, thus [ ] and in thcfe it was not thought necelTary to obferve the Ilile of inflruftions. The notes have been almoll entirely added fince the vote. ^/ a provincial meeting ef deputies chofoi by the fevcral counties^ in Pennfylvania, held at Fhiladelphia, July 15, 17 /^^ and continued by adjournments Jrom day to day. CHARLES THOMSON, Clerk. Agreed that, in cafe of any difference in fentiment, the queftion be determined by the deputies voting by counties. The letters from Bojion of the 13th of May were then read, and a fhort account given of the fleps taken in confequence thereof, and the meafures now purl'uing in this and the neighbouring provinces; after which the following RESOLVES were paired. JL and the mhabitants or this province, liege fubjedls of his majtfty king George the third, to whom ihey and we owe and will bear true and faithful allegiance Unan. II. That as the idea of an unconftitutional independence on the parent (late is utterly abhorrent to our principles, we view the unhappy differences between Great Britain 2ind the Colonies with the decpell diftrefs and anxiety of mind, asfruitlefs to her, grievous to us, and deftrudive of the beft interefts of both. ther country (hould be reftored, and a perpetual love and union fubfiH: between us, on the principles of the conftitution, and an interchange of good offices, without the lead infraflion of our mutual rights. Unan. IV. That the inhabitants of thefc colonies are entitled to the fame rights and liberties WITHIN thefe colonies, that the fubje^ls born in England are entitled to within that realm, Unan. V. That the power aflumed by the parliament of GreatBr'Uain to bind the people of thefe colonies, " by (latutes in all Cases WHATSOEVER," IS unconftitutional ; and therefore the fource of thefe unhappy differences. Unan. VI. That the a6t of parliament, for (liutting up the port of Boftony is unconftitutional; oppreffive to the inhabitants of that town , dangerous to the liberties of the Britijh colonies; and therefore, that we confider our brethren at Bofton as fuffering in the commor; caufe of thefe colonies, Unan, VII. That the bill for altering the adminiftration of juftice in certain criminal cafes within the province oi MaJfachufetts^Bay,, if pafled into an afl of parliament, will be as vnconftitutional, oppreflive and dangerous, as ^he ^6k above-mentioned, Unan. VIII. That the bill for changing the conftitutign of the province of Maffachufetts Ba)\ cftabliflied by charter, and enjoyed fince the grant of that charter, if paffed into an aft of parliament, will be unconilituiional and dangerous in its confequences to the Am£rican COlonies. Unan. IX. That there is an abfolutc ncceflity, that a congrefs of deputies from the feveral colonies be immediately afiembled, to conCult together, and form a general plan of conduct to be obferved by all the colonies, for the purpofes of piocuring relief for our fufFering brethren, obtaining redrcfs of our grievances, preventing future difienfions, firmly eftablifhing our rights, and rcfl:oring harmony between Great-Britain and her colonies on a conftitutional foundation, Unan. X, That, although a fufpenfion of the commerce of this large trading province, with Great-Britain, would greatly diftrefs multitudes of our induftrious inhabitants, yet that facrifice and a much greater we are ready to offer for the prefervation of our liberties-, bat, in tendernefs to the people of Great-Britain, as well as of this country, and in hopes that our juft remonftrances will, at length, reach the cars of our gracious fovereign and be no longer treated with contempt by any of our fellow fubjedls in England, it is our earneft defire, that the congrcfs (hould firll try thr gentler mode of dating our grievances, and niaking a firm and decent claim of redrefs. XI. Resolved, by a great majority, That yet notwithftanding, as an unanimiiy of coun* fels and meafures is iiidifpenfably neceflary for the common welfare, if the congrefs Ihall judge agreements of non-importation and non-exportation expedient, the people of this province will join with the other principal and neighbouring colonies, in fuch an aflbciation of non-importation from and non-exportation to GreatBritain as fhall be agreed on, at the congrefs. XII. Resolved, by a majority. That if any proceedings of the parliament, of which notice fhall be received, on this continent, before or at the general congrefs, fhall render it necefTary in the opinion of that congrefs, for the colonies to take farther fteps than are mentioned in the eleventh refolvej in fuch cafe, the inhabitants of this province fhall adopt fuch farther fteps, and do all in their power to carry them into execution. ought not to take advantage of the rcfolvcs relating to non-importation in this province or clfe where; but that they ought to fell their merchandize, which they now have, or may hereafter import, at the lame rates they have been accuftomed to do within three months iuft paft. Unan. XTV. That tl-e people of this province will bleak off all trade, commerce, and dealing, and will have no trade, commerce, or dealing of any kind with any colony on this continent, or with any city or town in fuch colony, or with any Individual in any fuch co* lony, city, or town, which (hall refufe, decline, or neglefb to adopt, and carry into execution fuch general plan as fhall be agreed to in congrefs. Unan. XV. That It is the duty of every memberof this committee to promote, as much as he can, the fubfcription fet on foot, in the feveral counties of this province, for the relief of the diftrefled inhabitants of BoJlotK Unan. XV!. That this committee give inftrudfons on the prefent fituaiion of public affairs to their reprefentativcs, who are to mecc next week in AlTembly, and requcfl them to appoint a proper number of perfons to attend a congrefs ot deputies from the feveral colonics, nics, at fuch time and place as may be agreed on, to cfFeft one general plan of conduft, for attaining the great and important ends mentioned in the ninth refolve. '^ ^ '- " ' Gentlemen, THE diflcnfions between Great-Britain and her colonies on this continent, commencing about ten years ago, fincc continually encreafin^, and at length grown to fuch an excefs as to involve the latter in deep diftrefs aifd danger, have excited the good people of this province to take into their ferious confideration the prefent fituation of public affairs. , The inhabitants of the feveral counties qualified to vote at ele6lions, being afibmbled on due notice, have appointed us their deputies; and in confequence thereof, we being in provincial committee met, efteem it our indifpenfible duty, in purfuance of the truft repofed in us, to give you fuch inflruftions, as, ac this important period, appear to us to be proper. We, fpeaking in their names and our own, acknowledge ourfelves liege fubje(5^s of his majefty king George the ibird^ to whom " we will be faithful and bear true allegiance.' •^('We acknowledge the prerogatives of the fovercign, among which arc included the great powers ot making peace and war, treaties, leagues and alliances Ipindi ^ us — of appointing all officers, except in cafts where other provifion is made, by grants from the crown, or laws approved by the crown — of confirming or annulling every aift of our afllmbly within the allowed time — and of hearing and determining finally, in council, appeals from our courts of juftice. '* The prerogatives ar? limited," as a learned judge obferves, " by bounds i) certain and notorious, that it is impoffible to exceed them, without the confent of the people on the one hand, or without, on the other, a violation of that original contra^,§ § And though we are ftrangers to the original of mod flates, yet we mud not imagine that what has been here faid," concerning the manner in which civil focieties are formed, is an arbitrary fidlion. For fince it is certain, that all civil focieties had a beginning, it is impoHible to conceive, how the member."!, of which they are compoffd, could unite to live together dependent on a fuprcme authority, without fuppofing the covenants abovementioned. ^ •- And in faft, u\|jon confidering the primitive ftate of man, it appears raofl certain, that the appellations of fovereigns and fuhjeds, mailers and Haves, are unknown to nature. which, in all dates impliedly, and In ours moft exprefsly, Ibbfiits between the prince and fubje(^. — For thcle prerogatives are veiled in the crown fcr the fupport of focicty^ and do not in- Nature has made us all of the fame fpecies, all equal, all free and independent of each other ; and was willing that thofe, on whom (he has bellowed the fame faculties, (hould have all the fame rights. It is therefore beyond all doubt that in this primitive (late of nature, no man hr.s of himlelf an original right of commanvling oihcrs, or any title to fovcreignty. There is none but God alone that has of lilmfelf, and in confequcnce ot his nature and perfcdions, a natural, efiential, and inherent right of giving laws to mankind, and of exercifing an ablolute fovereignty over them. The cafe is otherwife between man and man, they are of their own nature as independent of one another, as they are dependent on God. This liberty and independence is therefore a right naturally belonging to man, ot which it would be unjuil to deprive him againll his will. I J. p. 38. There is a bt.Mutiful paflage of Cicero' t to this purpofe . Nothing is more agreeahh to the fuprtme Deity, that goi'erns this univer e., than ci-vil Jcciities la^dofuly ejiabltjhed. When therefor;- we give tu lovereigns the title of God's vicegcfents upon earth, this does not imply that they derive their authority immediately from God, but it figuifies only, that by means of the power lodged in their hands, and with which the people have iuvefted them, they main- ' tain, agreeable to the views or the Deity, both order and peace, and thus procure the happinefs of mankind. ' But it is our misfortune, that vvc are compelled loudly to call your attention to the confideration of another power, totally diiTcrenc But it will be here objetJled, that the fcripture itfelf fays, that every man ought to be fubjcQ toihc fupreme powers, becaufe they arc eliablilhed by God . I anfwer, with Giotiust that men have eflabliihed civil focieiies, not in confequence of a divine ordinance, but of their voluntary motion, induced to it by the experience they had had of the incapacity which fcparate families were under, of defending themfelves againi^ the infults and attacks of human violence. From thence (he adds) arifes the civil power, which St. Fcter^ for this reafon, calls a human power, \|\| thouj^h in other parts of fcripture it bears the name of a divine inftitution t, becaufe God has approved of it as an eflablifhment ufeful to mankind %' <i> All the other arguments, in favour of the opinion we have been here refuting, do not even deferve our notice. In general, it may be obferved, that never were more wretched reafons produced than upon this fubje6l, as the reader may be eafily convinced by reading Puffendorf on the law of nature and nations, who, in the chapter correfponding to this^ gives thefc arguments ac length, and com< pleatly refutes them H. Id. p. 42, 43. our natural and civil liberties pall event.i and realon convincin^.^, u?, that there never exided, and never can txill, a Hare ilus fubordlnate to another, and yec retaining': the llii?hicn: portion of freedom or happinefs. ' ''^'' The imporc of the words above quoted needs no defcant; for the wit of m.ui, as wc apprehend, cannot pofTibiy form a more clear, concife, and compreiienfive definition and fcifence of flavcry, than thefe expitfilons contain. Thi'? power claimed by GrerJ-Britr.in, rtnl the late attempts to excrcife ic over tliefc colonies, prelent to our view two events, one of which muH: i?ievitably take pl^ce, if (lie (hall continue to infifb on her pretenfions. Either^ the colonifts will fink from the rank of freemen into the clafs of flavcs, overwhelmed with all the miferies and vices, provM by the hillory of mankind to be infeparably annexed to thar deplorable condition : Or, if they have fenftand virtue enough to exert themfelves in driving to avoid this perdition, they mud be involved in an oppofition drv-fadful even in contemplation. llomur^ jujiicc, and humanity call upor us to iiold, antl to tranrniit to our pollrrity, that libcrty» which wc rcccivtxi from our ancc(tors. It is not our du^y to leave wealth to our chilr^scn : But it is our duty, to leave liberty to them. No infamy, iniquity, (tr cruelry, ran exceed our own, if we, born and educated in a country of '.rcedoin, entitled to its blelfmns, and knowing their value, pufilanimouriy delerting the poll affigncd us by divine Providence, lurrender lucceeding generations to a condition of wretchedneH:, from which no human efforts, in all probability, will be fufficient to extricate them -, the experience of all llates mournfully demonfl rating to us, that when arbitrary power has been eftablifhcd over them, even the wifcfl: and braved nations, that ever fiourilhed, have, in a few years, degenerated into abjc6l and wretched vafTals, So alarming are the meafures already taken for laying the foundations of a defpotic authority of Great-Britain over us, and with fuch artful and incefTanc vigilence is the plan profecuted, that unlefs the prefent generation can interrupt the work, while it is going forward^ can it be imagined, that our children, debilitated by our imprudence and fupinenefs, will be able to overthrow it, when compleated? Populous and powerful as thefe Colonies may grow, they will dill find arbitrary domination no: only ftrengthcning with their ftrcngth, hut exceeding, in the fwifrncls of its prof^rclTion, as it ever has do.ic, all the artlcfs advantages, thar can acrue to the governed. Thefe advance with a regularity, which the d'vine author of our exiftence has imprLlTed on the lau.iable puriuirs ot his creatures : But dcfpotinn, * unchecked and unbounded by any laws'^ncytx fatisfied with what has been done, while any thing remains to be done, for the accomplilhmenc of its purpolcs — conliding, and '\ ;, capable • As virtue is nccenary in a republic, and in a monarchy honor, fo fear ik neccHury in a defpotic govornnunt: with rtrp;ard to virtue, there is no occafion for it, and honor would be extremely dangerous. 'iere the irnmenfc power of the prince is devolved intlrely upon th<.fe to whom he is pleafed to cntruft it. Terfons capable of fetting a value upon chemfclvcs would be likely to create revolutions. Fear mull therefore dcprefs their Ipirits, and extincailh even the lead fenfe of ambition. When the favages of Louifiaiia are defirous of fruit, they cut the tree to the root, and gather the fruit f . Thia is an «/w/V^/» of defpotic government. IJ.bcokV.c. 13. for a great number of laws. Every thing ought to depend here on two or t h r e e ideas ; therefore there is no neceflity that any new notions Ihould be added. When we want to break a horfe, we take care not to let him change his mafter, his leffbn, or his pace. Thus an imprcflion is made on his brain by two or three motions and no more. ; y. took V. ch, 14. '^•^ '""'' capable of confiding, only in the annihihition of nil cppofifion^-'\\o\y\\i its courlewith Juch unabating and deilruflivc rapidity, that the world has bccon7eits prey, and at this day, Great-Britain ;:nd licr domuiions excepted, there is fcarce a Jpot on the globe inhabited by civilized nations, where the velliges of freedom are to be; oblerved. To us therefore it appears, at this alarming period, our duty to God, to our country, to uurfelvcs,^ and to our poUerity, to exert ourutmolt ability, in promoting and cftablifhing harmony between Great -Britain and thefe colonies, ON A CONSTITUTIONAL FOUNDATION. For attaining this great and defirable end, we requell: you to appoint a proper ri. mber of perfons to attend a congrefs of deputies from the fcveral colonies, appointed, or to be appointed» Ly the reprefentatives of the people of the colonies refpedively in afferobly, or convention, or by delegates cholen by the counties generally in the refpedive colonies, and met in provincial committee, at fuch lime and place as fhall be generally agreed on: And that the deputies from this province may be induced and encouraged to concur in fuch meafurcs, as mav be devifed for the common welfare, we think it proper, particularly to inform you, how far, we apprehend, they will be fup\|)ortea \y, ihciL- condud by their conftituents. ''/-^''- ^ [In The affumed parliamentary power of internal legiQation, and the power of regulating trade, as of late exercifed, and defigned to be exercifcd, we are thoroughly convinced, will prove unfailing and plentiful fources of diffcntions to our mother country and thefe colonies, unlefs fome expedients can be adopted to render her fecure of receiving from us every emolument, that can in juflice and reafon be expcdled, and us fecure in our lives, properties, and an equitable ihare of commerce. Mournfully revolving in our minds the calamities, that, arifing from thefe diffcntions, will moft probably fall on us and our children, we will now lay before you the particular points we requeft of you to procure, if polTible, to be finally decided ; and the meafures that appear to us moft likely to produce fuch a defirable period of our diftrelfcs. and dangers. We therefore defire of you--- ,' First That the Deputies you appoint, may be inftrufted by you ftrenuoufly to exerc ihemfelves, attheenluing Congrefs, to obtain a renunciation, on the part of Great-Britain^ of all powers under the ftatuteof the 35 of Htnry the eighth, chapter the 2d.— of all powers of internal legiflation- -ot impofing taxes or duties internal or external— and of regulating trade, except with refpcft to any new articles of commerce, which the Colonies may hereafter raife, as filk, wine, &c. referving a right to carry thefc fiom one colony to another— a repeal of all ftatutes for quartering troops in the Colonies, or fubjedling them to any expence on account of fuch troops— of all ftatutes impofing duties to be paid in the Colonies, that were pafled at the acceflion of his prefent Majefty, or before this time •, which ever period fhall be judged moft advifeable-'Of the ftatutes giving the courts of admiralty in the colonies greater power than courts of admiralty have in England — ^of the ftatutes of the 5th of George the fccond, chapter the 2 2d, and of the 23d of George the fecond, chapter the 29th-'. of the ftatute for fiiutting up the port of Bofton— and of every other ftatute particularly afFeding the province of Majfacbufetts Bay^ pafTed in the laft feflion of Parliament. Tn cafe of obtaining thefe terms. It is our opinion, that it will be reafonable for the colonies to engage their obedience to the afls cf parliament, commonly called thea(5lsof navigation, and to every other afl of parliament declared to have force, at this time, in thefe colonies, other than thofe above-mentioned, and to confirm fuch ftatutes by a6ts of the feveral alTemblies. It is alio our opinion, that taking example from our mother country, in abolilhing the " courts of wards and liveries, tenures in capite, and by knight's Ccrvice, and purveyance," it will be reafonable for the colonies, in cafe of obtaining the terms before mentioned, to fettle a certain annual revenue on his majefty, his heirs and fucceffors, fubjedt to the controul of parliament, and to fatisfy all damages done to the EajiIndia company* This our idea of fettling a revenue, arifes from a fenfe of duty to our fovereign, and of cfteem for our mother country. We know and have felt the benefits of a fubordinate connexion with her. We neither are fo ftupid as to be ignorant of them ; nor fo unjufl: as to de* ny them. We have alfo experienced the pleafures of gratitude and love, as well as advantages from that connexion. The impreffions are not yet erafed. We confider her circumflances with tender concern. We have not been wanting, when conftitutionally called upon, to affift her to the utmoft of our abilities ; infomuch that fhe has judged it reafonable to make us recompcnccs for our overtrained exertions : And we now think we ought to contribute more than we do, to the alleviation of her burthens. Whatever rray be faid of thefe propofals on either (ide of the Atlantic^ this is not a time, either for timidity or raftinefs. We pertedtly know, that the great caufc now agitated, is to be conducted to a happy conclufion, only by that well tempered compofition of counfels, which firmnels, prudence, loyalty to our Sovereign, refped to our parent State, and atfe6tion to our native country, united mud form. By fuch a compaft. Great Britain m\\ fecure every benefit, that the parliamentary wifdom of ages has thought proper to attach to her. From her alone we (hall continue ro receive manufactures. ^0 her alone we (hall continue to carry the vaft multitude of enumerated articles of commerce, the exportation of which her policy has thought fit to confine to herfelf. With fucb pdtrts ef the world only ^ as (he has appointed us to deal, we Ihall continue to deal ; and fuch commodities cnly^ as (he has permitted us to bringirom them, we (hall continue to bring. The executive and €oninulin^ powers of the crown will retain their prcfcnt full force and operation. We (hall contcntcdly labour for her as affcdionate friends^ in time of tranquility ; and cheerfully fpend for her, as dutiful children^ our treafurc and our blood, in time of war. She will receive a certain income * from us, without the trouble or cxpence • The train of Officers, employed by Great-Britain, confume a very large part of what (he takes from us. She therefore increafes our dillrefles to make up for that coniiimption. They will hereafter grow more and more oppreflive, we more and morejunealy; ,flie more and more difturbed. We could raife aft-e^ualTum in a much more eajy^ tqualt and cheap manner, than ihe can do. The attention of fmall dates extends much more efficacioufly and beneficial!/ to every part of the territories, than that of i:he adminidra^ tion of a vaft empire. The reprefentatives in affembly, WHO ARE TAXED, WHEN THE PlOPLE ARE TAXED, AND ACCOUNTABLE TO Tij E M^vrtllkave doublc motires to take care, that the r«//f//g-^inoney ismanaged in the bed way. The Houfe of Commons would not bear to examine everf particular relating to the juft taxation o^ every county on thii continent, zn^ to fettle all the accounts fairly. Jf they couli go through the immenfe labour, it would be impofiible for them to do any other bufmefs In fliort, by not doing it, they would be uhjujl ; by doing it they would be ujdefu Equity and reafon demonflrate that fuch a power belongs not to them. Thfl fawn rgnfoning holdg ac to tho nffliMtim of moneyi We have had fome remarkable inflances on this continent fome itsu years ago, of the crown being according to all the forms of huf fiefs charged with Att'icleSt that never went to the ufe of the crown. Thefe vjtvt perquiftes^ and who could be fo puritanical as to blame the civil word. It is faid, our barracks coll about £. 8000 of this money — and that the barracks at another place^ not ueferving a ccm- expence of colle6ling it — without being conftantly dlfturbed by complaints of grievances, which (he cannot juftify, and will not redrcfs. In cafe of war, or in any emergency of diftrefs parifon with ours, coft;^. 40,000 fterliag. We built our own, ourfehest and were as faving and careful as we could be, it may be fuppofed. If money is raifed upon us by parliament ; of one thoufand pounds, taken out of our pockets, not one hundred, in all probability, will be ufefully applied to the fervice of the crown. Deficiencies will cnfue— they muft be fupplied— other afts are made -fiill otherstill our • " unrepre/ented blades of grajsy^ too frequently and clofely cut down and expofed to the burning heat of an unfetting Sun, ever" in its meridiarit^ perifti to their deep-, cfl roots. ** There is not upon earth (fays the excellent Gordon) a nation, which having had unaccountable magiflrates, has not felt them to be crying and confuming mifchiefs. In truth, where they are moft limited, it has been often as much as a whole people could do to redrain them to their trult, and to keep them from violence ; and fuch frequently has been their propenfity to be lawlefs, that nothing but a violent death could cure them of their violence. This evil has its root in human nature j men njoill never think they ha've enough^ whilft they can taKe more j nor be content with a part, when they can feize th« whole."! ' That the bufinefs of mod kingdoms has been ill managed, proceeds from this; it imports the /ow/r rank of men only, and the people (whofe cries feldom reach the prince, till it is too late, and till all is pad remedy) that matters Ihould be frugally ordered, becaufe taxes muft to her, we (hall alfo be ready and willing to contribute all aids within our power : And we folemnly declare, that on fuch occafions, if we or our pofterity fhall refufe, ncgledt or decline thus arife from tfjeir Aveat and labour. But the great ones, who heretofore have had the prince's ear and favour, or who hoped to have him in their pofTefllon, were fwayed by another fort or intereft ; they like profufion, as having had a profpeft to be gainers by it, they can eafily fet their account even with the ilate ; Tifmall charge upon their land is more than balanced by a great place^ or a large penJion.Y See the lord keeper North^s account of abufes in the condu£l and difpofal of the public money in the time of king Ch. II. § Thofe who, in our times, are the conduftors of the fame kind of dirty work, may compare the modern ingenious ways and means with thofe of their worthy predeceffors. Among others, pretended want of money in the treafury, in order to have a pretence for giving an exorbitant price for neceflaries. Lending the crown at % per cent, money which was raifed at 5 and 6. Paying with the public money, pretending it to be private, and taking intereft. Depreciating the public debts and funds, buying them of the holders at half their worth, and afterwards by intereft getting them paid in full* Pretending to give up all power in reconi> mending to places for a confideration, and then inftfting on recommending ftill, and fo getting both ways. Rolling over lolTes upon the crown, or public, while the gain was to fink into private pockets. Before he can be brought to account, he dies. The money ilnks into the pocket of his heir. He obtains a to contribute, it will be a mean and manifcft • yiolation of a plain duty, and a weak and wicked defertion of the true inrerefts of this province, whieh ever have been and mull be bound pardon of all his father's debts. Grofs frauds in office found out. Then new officers and falarics fet up as checks. The new prove as great knaves as the old, a^^d form a fcheme of (ollufion and mutual underdanding. But the public pays for all, and the power of the court is ftrengihened. An old placeman begs leave to fell. Pockets the money, and hj and by, through interell, gets a new place gratis Extravagant mm fquander their own money in their public employments of embafladors, governors, 5cc. and charge the public with more than they have really fpent, while what they really fpent was ten times more than neccffary. The bufinefs of old offices transferred to new : but the profits of the old dill kept up, though become finecures. An old fcrvant of the public retires upon a penfion. He who fuccceds him, by intereft, gets it continued to him. Another gets an addition to his falary, and then fells his place for a great deal more than it cod him, and fo an additional load ' is laid on the public : for the addition mull be connnued, bccaufe the place was bought. An annual fum is granted by the public for a public ufe, as keeping up a harbour, or the like. A private man, by intcred, gets a grant of the jobb; the public concern is neglefted, and the public poc» ket picked. Crown I .uds perpetually begged aiid given away to drengthen the court intered. The crown conftantly kept in debt, and parliament folicited to pay thofe debts occafioned merely by the voracity of the court. Commander! of fleets order a fuperfluous quantity of dores. By collu* fion between them and the dore maders, this fuperfluout quantity is fold again to the king, and the money funk ia their pockets. Sometimes the dorc-maders gave receipts for more than was received into the king's ftores, and the ^s„ i mone/ up in the profperity of our mother country. Qur union, founded on mutual compass and mutual bcntrfits, will be indiflbluble, at Icaft more firm, thin an union perpetually difturbcd by difputed rights and retorted injuries, money was divided among the plunderer). The king's works done by the day, whereas it would have been cheaper by the great. Money pretended to be coined gratii. Lifts of large Aims newly coined produced. But the contrivance was to make the pieces unequal, and then the too heavy pieces were carried back to the mint, and the profit funk in private pockets, &c. Secret feritice is a huge cloke thrown over an inlmcnfe fceue of corru>>tion; and under this cloke we muft not peep. Our court-men tell us, there muft be lat-ge I'ums expended in this way, and thofe Aims cannot be accounted for; becaufe the Jervices done for them muft never be knoiuHk Butwefind^ that the commons J, D. 1 708 addrefTed queen Anne for accounts of peniions paid for Jecret ftrvice to members of parliament, or to any perfons in truft for them ; and that ' the queen trdered faid account to b6 • laid befhre the boufe.f Contract are a great fund of minifterial influence. It is Well known, that our miniftry do not accept the moft rea^ JonabU offer; but the offer which is made by thofe, who have the grtattA parliamentary intereft; and that in war time, every man, who fumi^et for the go'vernmenty is enrichetl\ va France iht contrary, which fhews, that we manage our public money much worfe than the French miniftry do theirs. In the late war it is notorious, that feveral of our purveyors and commijfariet got eftates fufficient to fet them vp for earls and dukes. But as Burnet \|\| fays, * the re' gard, that is fhewa to members ai parliament among us, Secondly. If all the terms abovementloncd cannot be obtained, it is our opinion, that the mcafurcs adopted by the congrefs for our relief fhould never be relinqtiifljed or intermitted^ until tbofe relating to the troops,— internal Icgiflailon,"-innporuion of taxes or duties hercattcr, — the 35th ot Henry the 8th, chapter the What redrefs could a poor plundered, unrcprefented co. lony obtain againft a VtrrtSt fupported by a ftrong parliamentary influence. We know what fevcral governors of iiZ/ffo; £•« have dared to do. A governor of Giimttar has ventured to opprefs even the garrifon of that important place. The very drudgery of examining accounts, would probably fecure him. If cad, the injuries could not be rccompenfed. A fuccefTor might prove .as bad — ** Vi^rix pro-vin iaplorat.," .. ,- ■■, ,. .^'A,.,.. It has been faid in Great Briiain, that Lord Chattf^mt Lord Camden, and fome other great men, have taught the colonies to defpife her authority. But it is as little true as the multitude of invedives vented againft the colonies. The conflant pradice in thefe publications, is to confound fads and dates, and then to rail. It Oiould be rememberered, that, the oppofition in Ataerica to the ftamp ad was fully formed, and the congrefs held at New-Torif before it was known on this continent, that our caufe was efpoufed by any man of note at home. We (hould be glad to count fuch venerable names in the lill of our friends. They arc the true friends of our mother country, as well as of this ; and ages unborn will blefs their memory. But if every man in Gmit Britain, it carried by the ftream of prejudices into fentimepts, hofiileto our freedom, that freedom will not be the Icfi efteemed, or tli« fooner relinquilhed by Americans. 2d,— the cxtcnfion of admiralty courts,— the port of BoJ^en and the province of Majfachufeits Bny are obtained. Every modification or qualification of thefe points, in our judgment, (hould be inadmifTible. To obtain them, wc think it may be prudent to fettle Come revenue as above-mentioned, and to fatisfy the £.^y?India company. , . . TniRDLy. If neither of thcfc plans fliould be agreed to, in congrcfs, b^ut fome other of a fimilar nafjre (hall be framed, though on the terms of a revenue, and fatisraftion to the l adIndia company, and though it (hall be agreed by the congrefs to admit no modification or qualification in the terms t'.icy (hall infift on, \ 0 dtfire your deputies may be inftruded to concur with the other deputies in it; and we will accede to, and carry it into execution as far as we can. ., . ... . FouR-THLV. As to the regulation of trade— we are of opinion, that by making fome few amendments, the commerce of the colonies might be fettled on a firm eftablilhment, advantageous to Great-Britain and them, requir- out mutual confent. We defire to have this -point confidered by the congrefs-, and fuch meafures taken, as they may judgs proper. Im order to obtain rcdrcfs of our common p/icvanccs, we oblcrvc a general inclination ainong the colonies of entering into agicenicnts of non-importation and non-cxportation. We are fully convinced, that fuch agreements would withhold very Urge lupplies from Great-Britain »nd no words can defcribe our contempt and abhorrence ot thofe colonics, if any fuch there arc, who, from a fordid and ill judged attachnicnc to their own immediate profit, would purfue that, to ihe injury of their country, in this great Itrugglc for all the bleflings of liberty. It would appear to us a moll wafteful frugality, that would lofe every important poflcffion by too ftridl an attention to fmall things, and lofc alfo even thefe at the lafl. For our part, we will cheerfully make any facrifice, when neceflary, to preferve the freedom of our count\|y» / But other confiderations have weight with us* ^ We wi(h every mark ot refpe6t to be paid to his majefty's adminiftration. We have been taught from our youth to entertain tender and brotherly afFeftions for our fellow fabje(5ls at home. The interruption of our comrrerce muft diftrefs great numbers of them. This we earneftly defire to avoid. Wc therefore requeft, that the deputies you fhall appoint may be inftrufted to exert themfelves, at the congrefs, to induce the members of It, to confentto make a full and precife ftate of grievances and a depent yet firm claim of redrefs, and to wait the e^ C 29 J vent, before any other ftep is taken. It is our opinion, that pti'fons fhould be appointed and fcnt home to prcfent this Hate and claim, at the court oi Great -Britaw. ' . ..v ,#•.,.„ If the congrefs fliall chufe to form agreements of non importation and non exportation immediately, we defire the deputies trom this province will endeavour to have them fo formed as to be binding upon all, and that they may be < PERMANENT, fliould the public intercft require it. They ( annoc be efficacious, unlefs they can be permanent', and it appears to us that there will be a danger of their being infringed, if they are not formed with great caution and deliberation. We have determined in the prefent ficuation of public affairs to confent to a ftoppage of our commerce with Great-Britain only; but in cafe any proceedings of the parliament, of which notice (hail be received on this continenc, before or at the congrefs, fiiall render it neceflary, in the opinion of the congrefs to take further fteps, the inhabitants of this province will adopt fuch fteps, and do all in their power to carry them into execution. • ;. ■^"i'^^ ^^^'-' "^ This exrenfive power we commit to the con-d grefs, for the fake of prcferving that unanimity of counfcl and condudl, that alone can work out the ialvation of thefe colonies, with a ftrong hope and truft, that they will not draw this province into any m^afure judged by us, who mud IF 30 I be better acquainted with its (late than ftrangers, highly inexpedient. Of this kind, wc know any other ftoppage of trade, but of that with Great -Britain^ will be. Even this ftep we ftiould be extremely afflidled to fee taken by the congrefs, before the other mode above pointed out is tried:. But fliould it be taken, we apprehend, that a plan of reilri(ftions may be fo framed, agreeable to the refpedlive circumfVances ot the feveral 'colonies, as to rcndei Great-Britain fenfible of the imprudence of her (Jounfels, and yet leave them a nectflary commerccr. And here it may not be improper fo take notice, that if redrefs of our grievances car not be wholly obtained, the extent or continuance of our reftridlions may, in fome fort, be proportioned to the rights we are contending fbf, and the degree of relief aiTordcd us. This ittode will render our oppofttion as perpetual as our opprejjiony and will be a continual Clai m AND AscF.RTiON OF OUR RiGHTS. We cannot exprefs the anxiety, with which we wifti the confidcration of thefe points to be recommended to yor. We are perfuadtd, that if thefe colonies fail of unanimity or prudence in forming their refolutions, or of fidelity in obferving them, the oppofition by non-importation and non exportation agreements will be inefFc<5lual; nnd then we fhall have only the alternative of a more dangerous contention, or of a tame fub- Upon the whole, we (hall repofe the higheft confidence in the wifdom and integrity of the cnfuing congrefs: And though we have, for the facisfaftion of the good people of this province, who have chofcn us for this exprefs purpofc, offered to you fuch inftruftions, as have appeared expedient to us, ytc it is not our meaning, that by thefe or by any you may think proper to give them, the deputies appo'nted by you (hould be reftrained from agreeing to any meafures, thatfhall be approved by the congrefs. We (hould be glad the deputies chcfen by you could, by their influence, procure our opinions hereby communicated to you to be as nearly adhered to, as may be pofTible : Buv to avoid difficulties, we defire that they may be inflrufled by you, to agree to any meafures that fhall be approved by the congrefs, the inhabitants c^ this province halving refolved to adopt and carry them into execution. — Laftly — We defire the deputies from this province, may endeavour to procure an adjournment of the congrefs, to fuch a day as they fhall judge proper, and the appointment of a Handing commie- ' Agreed, that John Bickinfon^ Jofeph Read, and Charles Tbomfon, be a committee to write to the neighbouring colonies, and communicate to them the refolves andinftrudlions.''. ■^ 'AORftiD* that the committee for the city and county of Philadelphia^ or any fifteen of them, be a committee of correfpondence for the general committee ot this province. »' I ^ H E authority of parliament has within JL thcfe few years been a queltion much agitated i and great difficulty, we underftand, has occurred, in tracing the line between the rights of the mother country and thofe of the colonics. The modern dodtrine of the former is indeed truly remarkable ; for though it points out, what are not our rights, yet we can never learn from it what are our rights. As for example — Great'. >^'\7.n claims a right to take away nine-tci.,i: 5 of our eftates— have we a right to the remainiiig tenth ? No.— To fay we have, • This piece has been written in fuch haftc, under (o great indifpofition, and amidft fuch a confuiion of public affair" that it is hoped, its inaccuracies will be looked upon <v>^h indulgence. If longer time could have been beftowtr! ipcn ks corre^ion, it would have been at leafl fhortcr, if not ir.ore exaft. The firft appointment of a .committee to form a draught of inltrudions, was made on the fourth of lad month. See note on the extract, dated the i8th of July. IS a ' traiterons* pofuion, denving her fupreme Icgiflature. So tar from having property, according to thefe late found novelb, ws are our/elves a rropery. We pretend not to any confiderable fhare of learning •, K-ur, thanks be to divine Goodnefs, common fenft, experirnce, and fome acquaintance with the conltitution, teach us a few falutary truths on this important fubjed. Whatever dlfBculty rti occur in tracing the line, yet we contend, that by the laws of God, and by the laws of the conftitution, a line there muft be, beyond which her autnority cannot extend. For all thefe laws are § " grounded on reafon, lull of judice, ■\ and true equity," '•'■■ £"^ ' ^ ■ . mild, • § Parlt. Deh, 7. 409. " What of that? Shall not we ' give judgment, becaufe it is not adjudged in the books before? We will give judgment ACCORDING TO reason, and ■'if there be no reafon in the books, I will not regard them " Speech of /inderfon^ Lord chief jullice of the queen's bench, in the reign of jEZ/za^^/^. Gouldsb. Rep. g6. edit. 1653. '' ■' t »' It feems to me, that the natural juflkey which is a ' duty of man, ought to be ftyled the /)ar^«/, andnourijhe^y of 'every other 'virtue : and aflbredly, without this habit, a man 'can neither moderate his defires, nor be brave, nor wife, '^ For, it is a harmony^ and peace, of the whole foul; with a full concert of words, andadions: And the dominion of fuch a habit may be rendered more conf.icuous, if we examine the other habits of virtue. For the good of thefe is mild, and calculated to promote the freedom and wchare of men. The., objedts never can be attained by abolilhing every reftridion, on the pin of ihi' governors, and extingiulhing every right, on the part of the governed. Suppose it be allowed, that the line is not exprejsly drawn, is ic then(c to be concluded, there i5 n.j implied \\r,c ? No Englifh lawyer, we prefume, will venture to make the bold aifertion. ' The King may rejcd what bills, may make what treaties, may com what money, may create what peers, and may pardon what of- In the celeftialfv/Iem of the world, as it marfhals out the universal rule of things, which are thus decieed by God ; it IS providence^ znd harmony, and r/g^^/. In d civ /Jlate^ it is juftly ca.\\e6 peactt and good order. In a domejiic Jiate ^ it is the like mindedne/s of huiband, and wife, towards each o, therj the ^W T.w7/ of fubordinate members. In the ^o^v. it is health, and Jymmet>-y of parts; which are principal things, and much i^eioved by every livinfr creature. la the JouU it i.« ivijdom', that wifdom which arifes amongll men, from the knowlciige cfcau/es, and Horn natural jufl ice. Since there. ore, tliis habit doth thus itilcruC>, and prcfervc, the whole and every part ; rendcting all the fame, in heart, and in tongue, why may it not be faluted, by the univerfal voice; the parent and nourish er of evhrv fences, he pleases." J But is his prerogative rcfpeding thefe branches of it, unlimited ? By no means. The words following thofe next above quoted from the " commentarfcs on the laws of England" are—" unlefs where the conftitution hath exprefsly^ or hy evident consequence, laid downfome exception or boundary ; declaring^ that thus far the prerogative (hall go, and no farther." There are " fome boundarits" then, befides the " exprefs exceptions •," and according to the (Irong cxpreflion here ufed, " the conftitution declares there are." What " evident confequence" forms thofe " boundaries V mean nothing. If therefore, the conftltution ' DECLARES by cvideut confequence j" that a tendency to diminllh the happinefs of the people, is a proof, that power exceeds a " boundary," beyond which it oughi not to " go j" the matter is brought to this fingle point, whether taking our money from us without our conlent, depriving us of trial by jury, changing conflitutlons of government, and abolifhing the priviledgeof the writ of habeas corpus^ by feizing II " Of great importance to the public is the prefervation of this peifonal liberty : for if once it were left in the power of any, the higheft magiftrate, to imprifon arhitrahIjf whomever he or his officers thought proper, (as in France it is daily praflifed by the crown) there would soon he " A natural and regular confequence of this perfonal liberty is, that every Englijhman may claim a right to abide ,. IN HIS OWN country SO LONG AS HE PLEASES, and not to be driven from it unlefs by the fentence of law. Exile or tranfportation is a punifhment unknown to the common law. — * The king cannot conftitute a man lord lieutenant Si Ireland ugalnR. his will, nor malce him a foteign ambaflador. For this might in reality be no more than an honorable exile." I Blackstone 135 to 138. ** Thcfe precedents colledled by the reverend and learned judge, chief jultice Anderfon and all written with his own hand, do fully refolve for the maintenance of the antient and fundamental point of Liberty of the person, to be regained by Habeas Corpus, when any one is imprifoned-'* . Pari. Hift. 7. 418. -H '^ : cr tendency to diminifh our happinefs, than any cnormicirs al'^ng can commie under prcicnce of prer. rativ . caa have todiminilh chc happinelb of ,ic ful.jcdls in England. To come 10 a decifion upon this poinr, no long time need be required. To make this comparilbn, is dating the claim of parliament in die mod favourable light: Forit[)Uts the njfumcd power of parliament, to do, " IN ALL CA^ES WHATSOEVER," zvbat tbcypleafc^ upon the fame tooting with the ccknoivledgcd power of tiie King, "• to maka what peers— pardon what offences, &c. he pleafesy But in this light, that power is not entitled to be viewed. Such is the wil'dom of the EnglJIj conftitution, that it * declares" the King may tranfgrefs a ' boundary laid down by evident confcquence," even by ufmg the power with which he is ^;^/)r<?/}/y' veiled by the conftitution, in doing thoje very a5fs which he is exprefsly trufted by the conftitution to dO"-as by creating too many or improper perfons, peers; or by pardoning too many or too great offences, &c But has the conftitution ot England r;^prefsly ' declared,' that the parli.iment ot Great-Britain may take away the money of English colonifts without thtrir confent, and deprive them of tryal by jury, &c ? It cannot be pretended. True it is, that it has been {olemnly declared by parliament, that parliament /^'^j fuch a power. But that declaration leaves the point juft as it was before : For if parlia- ircnt had not the power before, the declaration could not give it. Indeed if parliament is really ' omnipotent," * that power is jufl: and conftitutional. We further obferve, that no Eng- lawyer, as we rcmei prcciil'ly the line beyond which, if a Ihall ' go," refinance becomes lawful. General terms have been ufed. The learned author of thofe commentaries, that notwithft^inding fome human frailties, do him fo much honor, has thought proper, when treating of this fubjedl, to point out the " precedent' of the revolution, as fixing the line. We would not venture any reflexion on fo great a man. It may not become us. Nor can we be provoked by his expreflions concerning colonifts ; becaufc they perhaps contain his real, though hafty fentiments. Surely, it was not his intention to condemn thofe excellent men, who rafting every tender confideration behind them, nobly prefenred themfelves agamft the tyranny of the unfortunate and milguided Charles's reign; thofe men, whom the houfe of commons, even after the reftoration, would not fufFcr to be cenfured. this qucllioii. — Wh<itconclu(5t of a prince renders refinance lawful ? James the fecond and his father violated exprefs rights of their JubjelUs, by doing what their ozvn expre/s rights gave them no title to do, as by raifing money, and levying troops, without confenc ot parliament. It is not even fettled, what violation of thole will jullity refinance. Bui may not fome future prince confining himfclf to the exercife of his own exprefs rights, fuch as have been mentioned, adl in a manner, that will be a tranfgrefTion of a ' boundary" laid down by ' evident confequence," the " conftitution declaring he fhould go no further" ? May not this exercife of thefe his exprefs rights, be fo far extended, as to introduce univerfal confufton and a fuhverfion of the ends of government ? The whole may be oppreffive, and yet any fingle inftance legal. The cafes may be improbable -, but we have feen and now feel events once as little cxpe(5led. Is it not poff.hky that one of thefe cafes may happen ; \i\idoes, has the conftitution exprefsly drawn, a line, beyond which refiftance becomes lawful ?. It has nor. But it may be faid, a king cannot arm again ft his fubjedts— he cannot raife money, without confcnt of parliament. This is the conftiiutional check upon him. If he fliould, it would be a violation of their exprefs rights. If their purfes are ftiut, his power flirinks. True.' Unhappy colonirts ! Our money may be taken iroin us— and ftanding armies eftabliflied over j: 41 J us, without our confcnt— every exprefsly Jec!dred conllitutlonal check diiTolved, and ihe modes of oppofition for relief fo contradlcd, as to leaver us only the mifcrable alternative of fupplication or violence. And fhefc, i; feems, arc r,he liberties of Americans. Becauje the conllitution has not • exprefsly declared"^ the line between the rights of the mother country and thcfe of her colonifts, therefore, the latter have no rights. A logic, equally edifying to the heads and hearts ot men of fenfe and humanity. We aflert, aline there muft be, and (hall now proceed with great deference to the judgment of others, to trace that line, according to the ideas we entertain : And it is with fatisfadion we can fay, that the records, ftatu'"trs, law-books, and moft approved writers of our mother country, thofe " dead but moft faithful couniellors" (as Sir Edward Coke calls them) ' who cannot be daunted by fear, nor muzzled by afFefbion, reward, or hope of preferment, and therefore may fafely be believed," confirm the principles we maintain. Liberty, life, or property, can, with no confiftency of words or ideas, be termed a right of xhtpojfejforsy while others have a right of taking them away at plea/ure. The moft diftinguilhcd authors, that have written on government, declare it to be ' inftiiutcd /^r fh bcfiefit of the feople 5 and that it never will have this tendency, where ic is unlhmtedy Even conqiitlt -'• itfelf is held not to deftroy all the right ot the conquered " But in order to fay fomething more particular concerning this fubjea, 1ft us obltivr that the natural Hate of rations \x\ rcfpea to each ot:.or, is that of fociety and peace. Thii fociety is likcwife a Hate of equality and inucpendmce, which cftablifhcs a parity of right between them j and en Phages them to have the fame regard and rcfped for cue another. Hence the gene al principle of the law of nations is nothing more than the general law of fociability, which obliges all nation.* that have any intercourfe with one another, to praflifc thofe duties to which individuals are caturally fubje(ft. ' Tht Te remarks mny ferve to £rive us a juft idea of that art, fo ncccHary to the dirednrs of flates, and diftinguifhed commonly by the name of polity. Polity confidt-red with regard to foreign flatcs, is that ability and addrefs by which a fovereign provides for the prefervation, fafety, profperity and glory of the nation he governs, by refpedling the laws cfjuftice and humanity ; that i?, without doing any injury to other ftates, but rather by procuring their advantage, as much as in reafon can be expeded. Thus the polity of fovereigns is the fame as prudence among private people ; and as we condemn in the latter any art or cunning, that makes them purfue their own advantage to the prejudice of others, fo the like art would be cenfurable in princes, were they bent upon procuring the advantage of their own people by injuring other nations. The rea/on of Jfate, fo often alledged to juftify the proceedings or enterpriies of princes, cannot really be admitted for this end, but inafmuch a? it is reconcileable with the common inter eft •' C/o//«i indeed acknowledges that the law of nature Is common to all nations; yet he eilablifhes a pofitivc law of nations contrddiilind from the law of nature; and reduces this law of nations to a fort of human law, which has acquired a power of obliging in confequence of the will and confent of all or of a great many nations. ^ He adds, that the maxims of this Uw of nations are proved by the perpetual praflice uf people, and the tellimnny of hiltoiians. • But it has bten juftly obferved that this pretended law of nations, contradiliindl from the law of nature, and inveftcd nc'vcrthelef* with a force of obliging, whither people consent to it or not, is a fuppofition dellitute of all toundaon.* « For I. all nations are with regard to one another in n natural iadppeudance and equality. If there be therefore any common law between them, it muft proceed from God their , common fovrreign. ••2. As for whit relates to culloms eftablifhcd by an cxprefi or tacit confent among nations, thefe cuftoms are neither of themfelves, nor univcrfally, nor always obligatory. For from this only that feveral nations have adtcd towards one another for a long time after a particular manner in particular cafes, ir docs not follow that they have laid them fjlves under a neceiTity of ailing always in the fame manner for the time to come, and much lefii that other nations are , obliged to confoi m to thefe culloms. ' ' -'9 ' i6 be bad or unjuft. The profeflion of a corfair or pyrate, was by a kind of confent, ^ftcemcd a long while as lawful, between nations that were not united by alliance or treat/. It feems likewife, that fome nations allowed themfelves the ufe of poifoned armsin time of war.jl Shall wc fay that ihefe were cuftoms authorifed by the law of nations, and really obligatory in refpeft to different people ? Or ihall we ' not rather confider them as barbarous pradices ; practices ^rom which every juil and well governed nation ought to refrain. We cannot therefore avoid appealing always to the law of nature, the only one that is really univerfal, whenever wc want to judge whether the culloms eftabhllied between nations have any obligatory efFefl. " 4. AlUhat can be faid on this fubjeil is, that when cuftoms of an innocent nature are introduced among nations; each of them is reafonably fuppofed to fubmit to thofe cuftoms, as long as they have not made any declaration to the contrary. This is all the force or f fPeA that can be given to received culloms ; bur a very different cifedl from that of a law properly fo called." ^v ViL MA K(^Pr inc. of na. la-wy I W./. 196 — lo^. ' But I will conclude with that which i find reported by fir Job:^ Davis, who was the kings fergeart; and fo, by the duty of his place, would no doubt m'Jntain, to the uttermoA of his power, the king's prerogative royal ; and yet it was by him thus faid, in thofe reports of his upon the cz\e oi tanijiry cujioms * That the king's of £«f/«W always ' have had a monarchy royal, and not a monarchy fignoral ;, I w fine, a po^er of government, in Its nature tending to the mifefy of the people, as a power that IS unlimited^ or in other words, a powe^r in which the people have ncJJoarc^^ is proved to be, by reafon and the experience of all ages and ch. 8. and b, 8. ch 6. It is held by the bed writers, that a conqueror in a juft war, acquires not a right to the propetry of thofe of the fubdued country, who oppofed him not, nor of the pofterity of thofe who did: Nor can the pretence of obtaining fatIsfa(rdon for the charges and damages of the war jurtify luch a claim. § In a free ftste, every man, who 13 fuppofed a free agent f ought to be, in (bate raeafure his oixin governor^ and theiefore a branch, at leafl of the kgifiati-vt povier- ought ta England rtftie in the njohole body of the people. And this power, when the territories of the llate are fmall and its citizens eafily known, ihould be exprefled by the people in their aggregate or colle£\ive capacity, as was wifely ordained in the petty republics of Greece, and the firil rudiments of the Roman ilate. But this will be highly inconvenient when the public territory is extended to any confidcrable degree, an'^ the number of citizens is increafed. In fo large a flate as ours, it is therefore very wif<;ly contiived that the people fhould do that by their reprelentatives, which it is impracticable to perform in perfon." 1 Blackstone 158. 159. The above quoted words are fuiScient of themfelves to refute the notion of virtual reprefentation" of Americam in parliament As to the argument drawn from fimilltude between the cafe of tho/e in England^ not qualified to vote by their property, »^hough pofTefled of a confiderable fhare, as proprietors of the funds — The Eaji India company— merchants— manufadurers &-c. and the cafe of colonifts, ilie true anfwer is, that there is no referablance whatever between the cafes. A few propofitions will prove it : But it may be proper to premife — ift. If repre/entation w^s intended hy the con/iitution of England, a complete reprefentation was intended ; for the reafon of having any, requires having a complete one, as being the bejl. 2dly. — If a «/w^/f/^ reprefentation was i«/^»<//ri/ by the conftitution, every deft£i\\\ the reprefentation, is againji the intention of the conjlitution. 3diy. If a refpeftc able part of the people in England is not reprefented, // is a defeSt, 4thly. if therefore, the intention of the conjlitution is to be regarded as the ' -^'^itution, it involves a plain abjurdity,io iXif&r a greater At^' . being conjlitutional, from a /mailer defedl which is uKConjUtutional. 5thly. The intention of the conllitution muji be regarded— and pra^ices inconftjient with its defign, muft be amended by it, if the happinefs ■•',■ ■ • . .. _' . which England argues, J " the efids of government cannot be anfwcred by a total diflblution of all happinefs at prefent, and of all hopes for the fu- which it means to promote and fccure, is to be rej?;arded. 6thly. If there is not fuch a reprtfentation in England^ as the conftitution requires, there ought to be. As to the refemblance above fuppofed. ift. If many inhabitants of £/»«land HAVE NOT a right to vote in the choice of members of the houfe of commons, there are many who have. 2dly. liot one inhabitant of the colonies, has that light. 3dly. Some reprefentation is better than nontt though a complete one cannot be obtained. The frji, is a de/e<3 of mode, the laUer an extiniiion of i\\t/ubjiance. There is, to a nice obferver of nature, tl perceptible difference between a deformed m^n and a DEAD man. 4thly. Proprietors of the funds &c. tho' they have no right to fuch vote, ai proprietors &c. may yet have it under another charafter, as freeholders &c. "Jthly. When afting as freeholders l^c. they may take care their intercfls ai proprietors ^c. for — 6thly. 1 heir being propi actors fjc, does not difqualify them, from acquiring and enjoyiag a right to fuch vote by becoming freeholders l^c. but /thly. By acquiring and enjoying a right to fuch vote, the colonifts muft ceafe to be inhabitants of the colonies — 8th!y. Their being inhabitants of the colonies ^ therefore difqualifies them from acquiring and enjoying th« rig it to fuch vote. — 9thly. If thofenot entitled to fuch vote in Eigland were not bound by ftatutes made there they wodd not be bound by ftatutes, nor taxed at all, though poffeft of great property — ' but lothly. The coloulits are bound and taxed by the afts of their aflemblies. i ithly. K'cn thofe not entitled to fuch vote in England, and incapable of obtaining it, have this protedlion, that beea']ti» reprejentatiites and their eh:lors ar^ bound by the laws made, as well as the reji of the people — and the connexions between the rc^rr/entatitts, their elcJiors, and the rejl of the peopUy all living together in the fame kingdom, are fo many and io intimate, that even the aSually unreprejented cannot be affeded, unlefb the reprefcntati'ves and tbeir tUdors are afFcded alfo. I2thly. Totally different is the condition of colonifts, if bound by flatutes generally. — ^y the a£ts of parliament for raifing a revenue in America, the commons ufe the words, ' give and grant." Can men give and grant what they have not ? Did any of chofe ads take a fingle penny out of the pocket of a finglc 6ivcr and grantor ? No. So far from it, that if there is any truth in the proverb, and money faved is money got, thefe " <^o«<i/?r». /«" gentlemen put money into their pockets by their f •• loyal and dutiful" generofity. Every individual of them acquired by beftowing. Pretenfions /i'aj to ^/'i/^ are fuch contradidionsto fad andfenfe, that in making them afandion ofinjulHce is fuughcfrom a principle of the conflitution, and in defcribing them, a folecifm in fpecch becomes a proper expreflion. It mud be acknowledged however, that the commons are more than found divines, for they improve upon the text, \ and ' coutit tneir kj$ for gain.'* Statutes might grind us, while not an tledcrui England would know or regard our fuft"erin^s—ii acquainted with them, he might think the flatutes inflidii>g them, just and POLITICAL, An open avowal has been made in par* hament— that it is ^ • the indispensible duty of par- I PmlippiatiS iii. 7. § Thcfe words arc extraded from the proteft of the lords on the repeal of the American ftamp-adt — §. 6. — 61 lordi w«re agimd tUf :-('pcal, 33 d them finned the proteft. ' We well know, that the colonifts are charged by nrnny perfons in Great Brit, in, with attempting to obtain fuch an exclufion and a total independance on her^ As well wc know the accufation to be utterly fit^fe. We are become crimmal in the fuiht of fuch perr)ns, by refufing to be guilty ot the higheft crime againft oi:rreivt.s and our poftenty. Nolumus leges G which liament to tax the colonies in order to ease the gentry And peoplf of Great-Britain." Let not j^mtricaus cver forget the loidly words! To underHand them fullyy we fhould confider — Our difputc includes not only the prefent taxes laid upon us. The univerfal property of England wasinterefted in Mr. liambdtn\ fuit, about a few (hillings. If the crown had a right to thojt ihiiling», it had a right to every (hilling «f e'very man in the kingdom. Great Britain is about ONE HUNDRED AND FORTY MlLLiOiMS OF POUNDS STERLING in debt. If (he can pay any fart of that debt, by taxing js, (lie may pay the luhole by taxing us, if we can raife the money. If we cannot, yet as we are upbraided continually in pamphlets and papers with the richnefs of our houfes, our furniture, our equipage, our tables, and our drefs, (he may be made to think we abound too much in thefc con'veniencies. If we are reduced to the condition of French peafants, it is no matter. We belong to the people oi Great- Britain: And all Britijh fubjeds, but jimericansy ma do vvhat they pleafe with their own. " It is her indifpenfible duty, fay their lordfmps,to cafe herfelf by taxing us ;" and furely there is virtue enough left in a J!?r////^ parliament, notwiihftanding all the dreadful intelligence Britijh writers fend us over, to perform that " duty,* exaAly. But this is not all. Th^ere are certain wicked which we are ftigmatized. [ We have committed the like offence, that was objeded by the polite and humane Fimbria againrt a rude fcnator of his time. VVe hav? " difrefpcol fully refufed to receive the whole weapon into our body." We could not do it, and live. But that Frenchmen and Spaniards, that in every period of twenty or thirty years oblige Great- Britain to add thirty or forty millions to her debt. Upon an average, fjnce the revolution, fhe runs annuviUy in debt about a million and an half. Can it be expeded, her mii/ulers will be kinder to us, than they have been to her ? Where will the demand upon us, where will our wretched nefs llop, if we have not refolution enough to defend ourfelvet. ? A ftatute intended to have force on the people of GnatBritain, is the cafe of a state ailing upon itself. A ftatute intended to have force on the people oi America ^ is the cafe of ONE fidte aSling upon another. The people of Great Britain, who in the firll cafe TxxtJubjeSi to the ftatute —in the fecond, are the abfolute fovereigns ivho impofe it on others, ' ** Virtual reprcfentation" then, as applied to colonifts — is, to borrow expreflions of the excellent archbirtiop Tillotfon, on another occafion, altering only two words — " An abfurdity of that monftrous and mafly weight, that no human authority or wit are able to fupport it. It will • make the very pillars of St." Stephens ' crack, and requires more volumes to make it good than would fill" WeJiminJIer Hall, Yet this ii\cJt defpicable notion has been the pretence, fir our felloiv fuhje^s f clapping inuficets to our breads, and taking our money out of our pockets. f ' Win their hearts, and you may foon have their hands and pur/es,' Wis the advice of oid lord Burleigh to queen Eliznheth. She was wile euoii;jU to take it. The world knows the confc- For thefe ten years pad we have been Inccffantly \\ attacked. Hard is our fate, when, to efcape the charader of rebels, wc mud be derrraded into that of flaves : as if there was no medium, between the two extremes of anarchy and defpotifm, where innocence and freedom could find repofe and fafcty. . ..... K J Why lliould we be cxhibired to mankind, as a people adjudged by parliament unworthy of freedom ? The thought alone is infupportable. Even thofe unhappy perfons, wholiave had the misfortune of being born under the yoke of bondage, impofcd by the cruel laws, if they may be called laws, of the land, where they received their birth, no fooner breathe the air of England^ though they touch her fliore only by accident, § than they intlantly become ireemen, G 2 Strange !{ 4 Geo. 3, ch. 1 5. 4 Geo. 3, ch. 34. 5 Geo. 3, ch. 12, 5 Geo. 3, ch. 45. 6 Geo. 3, cjb. 12. 6 Geo 3, ch. 52. 7 Geo. 3, ch. 41. 7 Geo, 3, ch. ^59. 8 Geo. ^, ch. 22. The rcfolves that colonics may be tried in England under the 35 Hen. 8.— The blockade of Bo/lon—the Rhodc-IJlatid court, &c. &c. To return to the charge againfl us, we can fafely appeal to that Bein^, Irom whom no thought can be concealed, that our warmeft wilh and utmoll ambitiun js, that we and our pofterity may ever remain fubordindtc to, and dependant upon our parent itate. This fubmilTion our rcalbn approves, our affcr6\ion dictates, our duty commands, and our interefl: enforces. If •To this contraclIiTlIon, the follovvJnu' raav be added — Her policy at onct to keep peace with her natural enemies^ and CO provoke her natural friends, whofe aflillance one day —and that day leenis to be approaching — in iheviciflitudcs of human affairs, great as (he is, (he may want ; — her intereft, as (he thinks, to proteii and to opprtfs PROTEbTAN r countries - to abhor a large Jlunding army and > yet voluntarily to put heifef under the abfolutf necelTity, ,of perpetuating an immenjely large one, to govern the many miJions of flaves (he expects (bon to have on this vaft continent. Two of the (hrcwdcU, though not belt emperors, that ever lived, Augujlus and Tiberius, prohibited every man of dilHiidior. from letting his foot in £^v//,becaufe of the importance o( that province to Rome. Hut Great Britait?, as if thife numetous provinces, much more remote irom lier, than Egypt from Rome, were o\ little confi-quence, willingly obliges herlelt to tru(t a mighty armed power into the hands of a Lbjeft, in thefe colonies, the ' tempting intereft of which fuHjeft and of the people, may ' engage them to unite in «-ftabii(hingan independant empire, on her own model. Great-Britain ojght not to forget, that Jlame was ruined by keeping (landing armies in her provinces. If this fubmiflion indeed implies a diiTolution of our conftltution, and a renunciation of our liberty, we lliould be unworthy oi' our relation to her, if we fliould not frankly declare, that we regard it wi h horror; and every true true EngliJIjman will applaud this juil diliindlon * The Privernates had revolted from the Rowans, hut were reduced. The quellion was, what judgment Ihou'.d be given againft them. Tliis is Livys account ol tj^e affair, in the 2 11 chapter of his 8th book. " Qiium ipfa per fe res aticeps eij'et, prout ciijurqne ingenium erat, atrocius mitiuivc fuaucntihus ; tuni inceriiora ofiinia unus ex Privernatibus legaiis lecir, ma if. couditionis, in qua iiatus efict, quam irgc'enti ncccflitaiis, mcmor: tjui, idtcrronatus a quodam trillioris fcntetificc au>itore, quam janam tr.eritcs P»ivernates cenlnet (" enm, inquif, quam meteiitur, qui Je iibertate di^nos ceut'cnt: cujus quum feroci refponlo intelliotes fados videret conlu; tos, qui ante Privernatium caufam impu'^i.alT'ir.t ; ut ipie ber.i^na interrogatione niitius rffponfum eliciret, f^''\Ji pcenam^ inquit, remittimui 'vobis, qualem ties factm njohijcum habitwcs /per emus? Si bonam tteleutis^ inquit, ^ Julam, tif perpctuam: Ji malam, hau/i diuturnatn. Turn vero minciii, necidan^bigue, Privernaiem qiiiiiam, >' iliis vocibus ad rebellandum incitari pacatos popu!o«, pars melior fena'us ad mtliora refponfum trahere, & diceie, Viriy ^ lileu^ ^uccem auditam^ an credi pcjje, ullum populum, aut hominem am: que, in ea conditioner cujus eum pegniteat, diH>ius, quam iienjj- Jit, manjurwn? Ibi pacem ejjejidam, ubi 'vcluntarii pacati put : tieque to Icco, ubi fer'vitutem cjje ^uelint. fidem Jjerandam ejje. In hanc (ententiam maxinie coiiful ipfe indinavir animos, identidem ad principes fententiarum coufulares, uti exaudiri poffet a pluribus, dicendo, Eo, 'emum, qui nihii. prceterqiiam deltlertate^ cogitent, dignos rjf-, qui Rornani fnnt. Jtaque & in fenata caufam obtinuere, & ex auftoritate Patrum latum ad popaJuin eft, ut Privernatibus civiTAs DARiTUR," and candid declaration, f Our defence neceflarily touches chords in unilbn with the fibres of his honed heart. They muft vibrate in fympathetic tones. If we, his kindred, fhould bcbafeenough to promife the humiliating fubjedion, he could not believe us. We fhould fufTer all the infamy of the engagement, without finding the benefit cxpedled from being thought as contemptible as we (hould undertake to be. ] But this fubmifiion implies not fuch infupportable evils: and our amazement is inexprcfiible, when we confider the gradual incieafe of thefe colonies, from their flender beginnings in the laft century to their late fiouriftimg condition, and how prodigioufly, fince their fettlement, our parent (late has advanced in wealth, force and influence, till (he is become the firft power on the fea, and the envy of the world — that thefe our better days (hould not ftrike conviction into every mind, that the freedom and happincfs of the colonids are not inconfiftent with her authority and profperity. The experience of more than one hundred years will furely be deemed, by wife men, to have fome weight in the fcale of evidence to fupport our opinion. We might juftly a(k of her, why we are not permitted to go on, as we have been ufed to do fmce our exiftencc, conferring mutual benefits, thereby (Irengthening each other, more and more difcovcring the reciprocal advantages of our connexion, and daily cultivating afFcdions, encouraged by thofe advantages ? [ What unknown offences have we committed againft her within thcfc ten years, to provoke fuch an unexampled change in her condufl towards us ? In the lad war, (he acknowledged us repeatedly, to be faithful, dutiful, zealous and ufcful in her caufe Is it criminal in us, that our numbers, by the favour of Divine Providence have greatly encreafcd ? That the poor chufe tr fly from their native countries in Europe to this continent ? Or, that we have fo much improved thefe woods, that if we can be forced into an unfuccefsful refiftance, avarice itfelf might be faiiated vy)th our forfeitures ? ] It cannot with truth be urged, that proje«Ils of innovation have commenced with us» Fadls and their dates prove the contrary, f Not a difturbance has happened on any part of this continent, t " The winds lift up the waves",— faid a wife manyet we read of a weak man, who fcourgcd waves — but he had not : aifed them. To excite commotions, and then to fcourge /tr bting excittd^ »« an addition to the wildnefs of a Xerxes, referved more particularly to diftinguifh the prcfent age, already fufficiently illuftrious by the injuries •iTcrcd to the rights of human paturCi To what piirpole ? The charge of our affcdlin^ one gre.u, or many Imall republics, muil app. ar as contemptible a madncfs to her, as it Hoes to us. Divided as we are into many provinces, -f and incapable of union, except ... , . agajnft f The piTilus of a Beccaritt, fufrgcHcJ to l.im the condition of* a larp,e einpiie verging into fervitudc — the only plan for faving it, — and the difficulty of executing that plan. ** An overgrown republic (lays he, and fuch a HBii'ed monarchy as that of Great-Britain with fuch an extent of dominions, may well be called, •' an overgrown republic,") can only he faved from dcfpotlfm, hy fuhdividing it into a number of tonfederate reiubl cs. But how is this praflicable f by a defpotic di£lator, who with the coyage of Syi/a, has a» much genius for building up, as that Roman l»ad for pulling down, ifh- be an ambitious man, his reward, will be immortal glory; if a pMIo^opher, the bleflings of his fellow citizens will fufficicntly confole nim for the lofs of authority, though he (hould not be infenfiblc to their ingratitude." What was argument in Italyj is reality to Great Britain, with this additional ciicumftance in her favor, that ftie muft always continue if fiie wifely conduds her affairs, though leis tiian all, yet greater than on^. The immenle advantages of fuch a fituation, are worthy the clofelt attention of [ every Briton. To a man, who has confidered them with that attention, perhaps it will not appear too bold to aver» that, if an archangel had planned the connexion between Great-Britain and her colonics, he could not have 6xed it have cliangcd human nature. L mighty raval power at the head of the whole— -that power, a parent Hate, with all the endfaring fentiments attending the relationfhip - that never could difoblige, but with dcfign — the dependant Hates much more apt to have tcuds among thcmfel vcs— Ih; the umpire and cootrouler thofe Uates producing every article necelFary to her j^reatnefs - their intereft, that (he flioulc I ontinue free and jlouriftiing — their ability to throw a cnnfiderable weight into the fcale, Ihould her government gcr UNDUi.v POISED — flic and all thofe Uates Protestant—are fomc of the circuinllances, that delim^ated by t:ie mafterly hand of a Bcccaria^ would exhibit a plan, vindicating the ways of heaven, and demo Ibating, that humanity and policy arc nearly related. An AleKunder^ a Ccefai ^UarUst a Lewis, and others have fought through fields cf blood, for univerful empire. Great- Britain has a certainty, by population and commerce alone, of attaining to the moft allonl;hing and well founded power the world ever faw. The circumllaiices of her fituation are new and ftriking. Heaven has offcied to her, glory and profperity without meafure. Her wif;.- minillers dildain to accept them — and prefer—" aptpper corn." So diredlly oppofite to the iniereO of Great Britain^ hai the condud of adminijiration been for lome time paft, that it may fafely be affirmed, that, ii their view was, to eftablifli arbitrary power over Great- Britain^ fchemes more dangerous could not have been laid. lo profefs this purpofe, would enfure a defeat. Any man, who had fuch a defign^ would firft take the opportunity of peace, to set one Let every feflion of parliament produce a frefli injury. Give no reft, or hope of reft. Let infult . added to infult, fill up the vacancies between the feflions. Tcafc and perfecute into oppofition. Then let ininillers themfelves rejoice in the freedom of the prefs. Let every adion of the oppreffed be exaggerated. Let innumerable falfe invedives be vented in pamphlets and newspapers. Let all the provocations and excufes be concealed from public {ight as much as poflible. Load the devoted with the terms of tray tors and rebels. Nearly in this way Scotland WaS treated by the arbitrary minillry of Charles the firft. But the pajliament and people of England had common fenfe and virtue. The bafc* deccpdon could not pafs upon them. They faw the fr are laid for thetn\ and refented it fo deeply, that an arrr.^ of Englifijmen fied before an army o{ Scotchmen iX Nenvhurn. For once it was glorious to fly. But it required Englijh head- i: EngUjh hcar":s to undcrftand and to ad the part. Thus :he colonies have been treated. At laft a ci''il war may be worked up. It fliould be cuniidered, \>^ Lord Marti'field expreffes it — .\hether ** th; play is worth the candle." In fuch a war, every vidory will be a defeat. If the colonics are fubdu'^d, vaft fums muft be raifed, and a prodigious. army muf; be fupported, to keep them in fubjedion. Great-Britain muft feel the weight ot that influence, added to the power of thecrown. The colonies are encreafing. Who can computc'the extent and efFed of fuch an influence^ ? Undone by her victories, t " Bit, on the other hand, it i$ to be confidcred, that «very prince, in the firft parliament after his acctffion, has by long ufage -K tru'y royal addition to his hereditary revenue fettled upor him for his life; and has never any occafion to apply to parliament for fupplics, hut upon fome public neceflity of the whole realm. This reftores to him that conftitutional independence which at his firft accefjon fceme, it muft be owned, to be wanting. And then, 11 2 of tones, (hc«z/y? refign her liberty or fomefuture monarch WITH HER colonies, unlcfs Tiic firfl lofes thtm in another way. If (he is unfortunate, pubiic calamities may make great changes. Such changes feem to be intended by fome men. Great-Britain has been leJ into the Rulicon, She has not yet paft it. We confider the hoftilities already prac- tifed, with rci'ard to power, we may find pci-haps that the handi of go\ernmeiu are at leaft fuflicietuly '"ircrigtheiied; and iliat an Englifirt nionarcl' is now in no danger of being ovcrhorne by citlier the nobility or the people. The inftrumcnts of power are not perhaps fo open and avowed as they formerly were, and thjrefore arc the lefs liable to jealous and invidious rtflevSlions; but they are not the vtilcer upon that account, lu fliort, our national debt and taxes (hefidcs the inconvenicnoies before-mentioned) have alfo in their natural coiifcqucnces throwii fuch a weight of power into the executive fciie of government, as we cinnot think was intended by our patriot ancrflors; who gloriouily ftruggled for the abolition otV the then formidable p r ts of the pverogativc, and by an unaccountable wanf of foi-efight t (hiblinied this fyfteni in their ftead. Tbt entire colleHion and nunaoe-nent of fo vajl a revenue, being placed in the handi of the crown, luvc given life to inch a mu'titude of new ofTicers, creited by and rcmovcaljle at the royal pleafure, that they have extended the influence of government to every corner of tke nation. Witntfs the commifioners, n\<.\ the mullitude of dependenti en the culloms, in every port of the kingdom; the commtfionersofexcife, Axid their tin /neroKsfuball ems, in every inland diffriifk: the fajlmajien, and thc\v fervants^ pi.intcd in every town, and upon every public road; the ccmmijjiofiers of Ike Jiamps, and their i/iy/rilutors, which are full as fcat«^cred and full as nunierou-,; the offieert of the fait duty, which, though a fpecics ofcxcifc and conduiSred in the fame manner, are yet made a diftioi^l corps from the ordinary managers of that revenue; thejurveyors of houfes and ivindowi; the receivers of thi land tax; the nunagers of Lttarie^; and the commiJ/ioH' en of hackney coaches; ail which are either mediately or immediateJy appointed by the crown, and removeable at pleafure withn\ii any reafon alTi^ned : tkcfe, it rcquiits but little penetration to i'te, muft give that power, on wl»ieh they depend for fubfiftence, an influence nioft amazingly exteniive. To this may be added the frequent opportunities of conferring particular obligations, by preference in loans, fubjcriptioiis, tickets, remittance^ and other money tranfaHioHS, which will greatly encrcafc; this influence ; and that over thofe pcrlbns vrhofc attachment, on account of their wcikh, is fre« " <jueutly chants, tlfed, as the rranceuvres of a minirterlal war, "VVe know the niachinatioiKs formed a'.>ainft us, and the favourite publications indulhiouflv ipread abrt;ad, to excite a jcaloufy of us among our Bntijl) brethren. We know how acceptable to many an caitlujuake would be to " hnk fomc of the colonies in the oceai;" -and how pleafing, to cmplov the reft * in raihng Jlaple comnu/diiies ;" 1 hat we are thought ' too numerous," and how much it would be judged by fome for the intereft of Great Britain, if a peltilence fhould fweep off a million and a half of us. Theft" wonderful lucubrations have notefcaped us. But here we are, by Divine Providence, three miliions of fouls. What Cin be done quenrlythc mofl dcfirablc. All this is thcnatiira), though perhaps the uutortlctn, tonltquencc of erf(5ling our funds of cicdit, and to fupportthcmcft<hlilliingour prcfcut perpetual taxts: the wholcof" vvhiclj is intirely new lincc the rcftiration in 1660-, and l)y tar the greatcft pait fiucc the revoluti()n in 1688. Aud tlic lame may he faid with rei gaid to the officers in our numerous army , and ihe places whicli the army has created. All whicli put together givrs the executive power fo perfuafive an energy with reipeiTl to the ptrlnns themfclvcs, and lb pievai! ^^j, an intertfi with their friends aud families, as will amply make amends for the iofs of rxternal pn rogative. " liut, though this protufion of offices Oiould have no eflc(£t orx individuals, there is ftill another newly acquind branch of power; and that is, not the influence only, but the force of a dtjciplwed army : paid indeed ultimately by the pccple, but mimcdiateiy by the crown; raifed by the crown, officered by the crown, commanded by the crown. TUcy are kept on foot it is true only from year to year, and that by tlu power of parliament ; but during that year they mufl, by the nature of our conftitution, if raifed at all, be at the abfolute difpofal of the crown And thcie nted buJ: few words t() demonflratc h>>w great a trufl is thereby repoied in the prince by his people. A trufl, that is more than equivalent 10 a thoufand little troublefome prerogatives. " Add to all this, that, befides the civil /?/?, the immevfe r^f^Hj«c of almoft feven millions flerling, which is annually paid to the creditors of the public, or carried to the fuikingfund, is firfl depofited in the royal exchequer, and thence ilTued out to the refpective offices of payment. This revenue the people can never rcfufe to raife, bccaufe it is made perpetual by aifl ol^ parliament ; which alfo, when well confidered, will appear to be a truft of great delii^acy and high importance." with us ? If we were tobeconfidered, only as jjrROTBSTANT alliest we oughc to be elleemed by a wife peopie. Such a people certaiuly would not be careful to difunite us from their intcrcll -to make us foes when ihey mi^ht have us friends. Some ftate? have ihouv;i.t it true policy to j^rant greater indulgences t^) rem-^te dominions, than were enjoyed by themfeives : An. I this policy ha<' been much applauded. The enjoyment of va1ual)le privileges bv inferior Hates, under the proteilion of a fupcrior, is the llrongcll bond of dependance. Why (hould wl- prefer a dcpendance on GreatBiitain to a dependance on France^ if we enjoy lefs freedom under the former, than we mav under the latter? "/'/>mijjmum impet iunt, quo obedkntes gaudent" — or as lord chie£ jullice Coke expreHls it, in his comment on the 25th of Ed~ cward the third, ' the tlate of a king llandcth more i^fJurcd by the love and favour of the fubje.^, than by the dread and fear of laws, &c.'\| Ought Gr^^-2?>-;/i3y« to defpife the advantages 11 Great- Britain put hciCelf to a very confidei rfl)!e expeuce lafl war in dccnce of Portugal, bccaufe thu kin\|;'ioin was litr ally, and fhe dttivt-d jJieat advintaj»ts from ^m intercourfe with her. But what are thofc auvaiiuj^cs or the afT.vilions arifinj; ftom them, when compired to tlic advantages and alLvVl ifis thar c mnccft rhcfc Colonics with Grecit-Brltmn ? W<>rds cawnot <-x'/» tl's the furprizc, that men frte from \|).iflion muft feci, on con'.KKrir.g her impt)Iicy, in labouring to disj )in from lit^iTcIf the only tiu<; rrleiidi Cut l»a> in the world. If her nilnifUrs were penfioncrs of France and s/>7/V, they could not purfue mcafurts more picahng and advantageous to to ihofc kingdouiii. f " During all our happy days of concord, pirtly from ournatlonai moderation, and paitly from the wifJ' in, and fametinies perhaps from the farelefsntTs (.f our miniRcis, rliey h.ive beeu truftcd in a good me^fure with the cuiitr m uiaj^ rii.;iit of their affairs; and the (ucctfs they have met with ouolu i.> ho to us an ever memorable proof, thatTHc tr#k \'<r of c") vkr n m knt (f^^NOT GOVERNING TOO M u C'H And why (hould frieudOiip and gratitude, andlongattachmcnts, whichiiif i'C I'l therclilliandfwcctiiefs of private life, be fuuporci! to be )f nn \vc!(»ht in the intercourfe between great commiuutlts ? Thufc are piinoii k^'of human nature, which aA wirii much greater ct.taintv on numbers thin on individuals. If properly ciiltivatrd ihty niiy to u<. be prodinSive ot tHe noblcfl benefits; and, at all cveuts, will nt-iiher IciTen the extent of our power, norfi;ortcn tiu duration of it." of ambition. No. Our highcfl: pride and glory has been, with humble unfufpcifting duty * to labour in contributing to elevate her to that exalted flation, (he holds among the nation^ of the earth, and which, we ftill ardently defire and pray, fhe may hold, with frefli acceffions of fame and profpcrity, till time (hall be no more. (hould be guilty of treafon againft our fovcreign and the majefty of the people of England, if we did not oppofe them. England mull be favcd in America. Hereafter, (he will rejoice that we have rejijted — and thank us for having affended her. Her wifdom will in a fliort time difcover, the artiiices that have been ufed by her worll enemies to enflame her againft her dutitul children ; that Oic has fupported not her own caufe but the caufe of an adminiftration ; and will clearly dillinguifh, which will mofl conduce to her benefit, fafety, and giory, nvell treated and affeSlionaie coUnies, or millions of Jlavei^ an unnatural encreafe of her Jianding forces, and an addition to the infiuenct of tht cronun, defying all calculation. i* • It has been fuggefted, " that fubje£ls fometlmes err, by not believing.that princes mean as well as the> do" — But, theinftances are numerous where princes and their courtiers err, by not believing, that fubjcf\s mean as well as they do. flifllon, wc find ourfelves obliged to oppofc that fyftem of dominion over us, arifing from counlcls pernicious both to our parent and her children — to drive, if it be poflible, to clofe the breaches made in our former concord — and flop the fources of future animoficies. — And may God Almighty, who delights in the titles ot juft and merciful^ incline the hearts of all parties to that equitable and benevolent temper, which is neceflary, folidly to ellablifh peace and harmony, in the place of confufion and diflenfion. The legiQativc authority claimed by parliament over thefe colonies confifls of two heads— firft, a general power of internal legiQation ; and fecondly, a power of regulating our trade: both, flie contends are unlimited. Under the firft, may be included among other powers, thofe of forbiding us tof worlhip our creator in the manner we think mod acceptable to him— impofmg taxes on us — colleding them by their own officers enforcing the collection by admiralty t The army under the command of general Gacf, in the pravince of Majpuhujltts Bay alone, amounts to feveral thoufand men— kept there ivtthout con/tnt 0/ their ^JJ'tf^^b\,^ and to be augmtntui as \\ie general (hall think proper. A miniftCT declared in the houfe of commons, that he Ihould " always confider it as a part of the conftitution that the military (kould aft under the civil authority." But, by order, the commande. in chief of the forces has precedence of a governor, in the province under his government. By his majefty's ordtrt tranfmitled in a letter dated the 9th of February \i6f^, from the fecrctary of ftate to the commander in chief, it is declared, •* that the orders of the commander in chief, and under him, of the brigadiersgeneral, commanding in the northern and fouthern departments, in all military affairs, Jhall be supreme, and muft be obeyed by the troops, as fuch, in all the ci'vil govern' ments in America. That in cafes, (where no fpecifick orders have been given by the commander in chief, or by the brigadier-genera) commanding in the diilrift, the civil governor in council, and where no council there fubfiils, the civil governor, may^ for the benefit of hit government^ give orders for the marching of troops, the difpofiiion of them, for making and marching detachments, efcorts, and fuch purely military fervices within his government, to the, commanding officer of the troops, lubo is to give proper order Jor carrying the fame into execution : Provided they are not ^ ««itaditfory to, or incompatible luithy any order he may have feceived from the commander in chief, or th« brigadiergeneral of the district." ' . In May 1769 the houfe of reprefentatives for MnffachufetsBay, requefted governor Bernard " to give the necelTar/ and effedlual orders for the removal of iht forces by fea and land oat of the pott oi Bojlon, and from t\\t gate of the city, he anfwered— •* Gentlemen, 1 have no authority over his majefty's />////« /^"/'O''' or his troops ivithin this toun, nor can J give any orders for their removal. declaring Thus, our governors, the captains- general and commanders in chief, reprefenting the fovereign, and known to the conllitution of thefe colonies, are deprived of their legal authority, in time oy peace, iy an order — and a perpetual MSiatorial poiuer eftabliQied over as. To accomplifh this great pur^ofe, it was thought proper during the lall war, to change the mode of granting military commifHonsi and to pafs that to the general in America under the great /eal. It is not known, whether this uncommon forjnality has been obfcrved with regard to the major-generals ff the refpeSi've ■'■ districts." § The Germans \i2L)it been juflly celebrated in different ages, for fagacity in promoting the arts, and for martial spirit ; yet how unhappy have they been made in a Ihort period of time, by that fingle engine of arbitrary power, a Jianding army. Their diftrefs was wrought up to fuch a degree, that thoufands, and tens of thoufands, relinquifhed their native country, and fled to the wildernefles of Jimetica. It was a way of thinking and afting that became them. For Germans may truly be called the Fathers of Englijhmen. From \ Germany came their anceflors and the firft principles of the conllitution. Germans therefore feem to be more juftly entitled than other foreigners to the bleflings of that conHitution. To enjoy them, in this free country as it then was, they came here, but now unfortunately find, arbitrary Gonjernment and ajianding army purfuing theia even into thefe woods. Numbers of them now in thefe provinces, have ferved in the armies of the feveral princes in Germany and know well, that one reafon with their rulers, for putting fwords into their hands was to cut the throats of their own fathers, brothers and relations who declaring any a£lion, even a meeting of tch fiii.iUelt number to confider ot peaceable modes to obtain redrcfs of grievances high trcafon— taking colonills to Great Britain to be tried \|1— • exempting " murderers"-}- of colonifts from punifhment, by carrying them to England^ to anfwcr indidlments found in the colonies— § (hutting up our ports —prohibiting us from flitting J iron to build our houfes,— -making ^* hats to cover our heads, or clothing to cover \, the reft of our bodies, &c. f 4. . •• ^ , . In mifeijes. Their former foverelgns are now compleating, it is faid, the cruel tragedy of tyranny. They will not fufter thofe they have made wretched, to fcek for a more tolerable exillence in fome other part of the globe. It is their duty, fay thcfe unfeeling princes, " to be unhappy, and to renounce all hopes of reiierV* They are prohibited from leaving iheir country. Thofe who have already efcaped into thefe colonies, reinember what they and their parents fufFered in Germany. The old tell the ftories of their oppreffions to the younger; and however improbable it may app^'.ar on the other !ide of the Jtlantic, it is aflerted by perfons well acquainted with this people, that they have 'very /;///(? inclination to suffer the same ckuelties agaiiy in America. 4-t \f (ireaf Brit'iin has a conftitutional power to prohibit U9 from flitting iron as pe has done, flie has a conftitutional power, tliat is, a rights to prohibit us from raifing grain for our food; for the principle that fupports one law, will '" ' In our provincial legiQatures, the beft judges in all cafts whatfuits us--.fountit'd on the immutable and unalienable rights of human nature, the principles of the ccnlHtution, and charters and grants made by the crown at periods, when the lupport the other. What a vart demand muft be made oa ^er for this article, and how firmly would her dominion be eaubl ihed, if wc defended whoily on her for our daily bread ? Hei- modern writers- confider coloniils as flaves of Crc.it Britain iliut u^ in a a-ge workhoufc, conllantly kept at labour, in procuiir.g fuch jnateriids as ihe prciciibcs, and weanng fuch cloaihes as fne fends. — Should Oic ever adopt the meafiire abnvemer.tioned, and on our coniplaints of grievances, withhold food from us— what thfp ' why STitRVHD To fay in fuch (a/e we flionld have any other ri^ht, would be a '* traiterous and rebellious denial of the fupreme legillatare of Qrtat B^itain^* for Ihe • has power cf right to bind us by Ilatutes in all cases whatsoever. ." Let not any perfon objcft that the Aippofition of fuch a ca(e is the fuggellion of fancy. The Carthaginians, thofe mailers in the fublinie politics of commerce — politics that have projuced lb many dieadful fccnes u^on earth, fojbad the Sardinians to raife corn, in order to keep them in due fubjec\ion. The Eall Indies y St. Fincentt, the proceedings at Rhode JJJand, and the Bojion adl, &rc. give rife to many alarming appiehcnfions in America. There are few men on this continent would be ai much furprized at tl'at meafure, as at fome late meaiures. The beginnii)g julli/ies any apprchenfions. Puwer debauches the affedions. The improbability of ca'es happening, is no anfwer in fuch important conlidcrations. The laudable fpirit of commerce may be inflamed into rapacity and cruelty in a nation as well as in an individual. We muft regard the power claimed by power of making them was iiniverfally acknowledged by the parent (late, a powtr fincc frequently recognized by herj-'-fubjed to the controul of the crown as by law cftablilhed, is veiled the exclufrjc right of inlernal k^i aiion. C)$at Briiain, not folely her will or contingencies depending on that WILL. If Ihtr affixes no liiniis to her poTVir why Ihould we alHx any to iti rJ^cJIjF ' 1 know (lays Mr. HnaMyj it is next to impofiible, ihat any fuch cafe ihould happen: But it Tuch thint^b be fuiJ, and fuch cafes, /;; effci'l, be put, it is ncceflkry to fpeak, upon the fuj [ofnion of jucb cajes. — And mc thinks it is but a narrow fpirftcJ proceeding in us to go jull no farther in our notions^ tha:i a compliance with eur oxvn prefint iomluion I'orceth us\ to exclude fioiu our regard the condition ot all othtr n tions, nnd all cajh^ but jail that, whicli hath happened lail of all i;i our own." That the plan of governing us by withholding w^c^^nW^ life has been confidercd, and in what li^jiit wlonies are viewed at home, the following extrads will partly fliew." • ** It a[>pearb that the original and gr:ind evil attendinrj them was the fcttiement oi Jo conjiderable a part \\\ a climate incapable of yielding the commoditiis wanting ia Britain. ' Thefc northern colonies, long after their difuj>vanta' geous natur.' uas known, were continually increafed b/ fiefii rnlgrativins from Etiro/e; which, as I before obfervc.l, ought totally to I'ave been prevented, and fuch migraiicns have been encouraged onlv to the beneticiai colonies. «' Since the late war, Britain laid the tra«.le of th.e colonics under fome very ftridl regulations, which certainly cut off many inlets by which they formerly received much Spanijh and Portuguefe coin. The principle upon which fuch regulations vv^ie formed, of fecuring to the moiher country alone all matters of ccmmaCe^ 1 have already attempted to prove/'/,'/ and necejfary. ,,, " When vert them into planters. •' I muft think this point of foch great importance, as to extend probably to the annihilation of manufaciur.s ii) our colonics — To conclude, it is. in the prcjpolcd fettlcment on the Ohio we muft firji look for hemp and flax ; as fuch great numbers of the old Ameritan tarnicrs ha\e removed and fettled thcic, which may, in iholc feiiile ivztXs, be cultivated in fuch abundance, as to enable us to underfell all'thc world, as well as fupply our own conlumption. It is on thofe high, dry, and healthy lands, that vineyards will be cultivated to the bell advantage, as many of thjfe hills contain quarries of ftone, f and not in the unhealthy fea-co(ls of o\xr prcfent colonies. To thefe we (hould bring the fettlers from Euro/e, or at leall fuffer none to go tiorift of Nenjo-Tork ; b^ which means our numbers would increafe in thofe p4rts, where it is our intercll they Ihould increafe ; and the report of the fettlers from the new coloify on the Ohio would be a conllant drain of people from our a«/ro//tf^/^ northern ones, by whi^h means they would, in future times, as well as the prcfc/it, be prevented from extending their manufadlures. ** What 1 (hall therefore venture to propofe is, that the government, through the means of afeiu merchants acquainted with the American trade, that can be tolerably depended upon, fliould eftablifli/zii^orjat Bofton, V hiladelphia, Nfw Torkt and a few other ports, for the fale of fuch cargoes of Britfjh manufactures as fhould be conligned to them ; and to confift of fuch particularly as were moll manufaiflured in the province, with diredions immediately and continually to under/ell al! fuch colony manufadures. By this means the opQration of the fucceeding meafures, from the number be executed. «* The fliips which carru'd out Aich cargoes (hould be large bulky ones, of eight, nine hundred, and one thuu< {and tons burden, for the fake of bringing large quantities of deals, &c. hack, at a lifs propo tionute t^xpence; and, previous to their arrival in America^ cargoes of theft (hould be ready for them. Trie col')i)ills fhuuld be enj^aged to work their irou mines, and gt t the produd ready in bars, &c. and va(l quantities of deals and fquared timber icudy for loading the (hips : All which, on the ceiiaia and immediate profpcd of a fulc would eafily be effcdcd ; as it is well known they have more than once proved to the legifla* ture, that they could iupply ^1 Europe with thefe articles, had they but the demand, to among the colonies. •* If the fugar illands contained ten millions of people, AS DEsTiTUTii OP NECESSARIES as they are at prefcnt, J? r/ra;/t would be as sure of their allegiance as Oie is at prefent -provided no power more formidable than hcrfelf at fea arofe for their protedion. • The firll dependancs oX our colonies, as well as all their people, is, to change the terms a little, upon corn worked into bread and iron wrought into implements ; or, in other words, it is upon necejjary agriculture and necfjjury ' manufadures ; for a people who do not pofl'cfs thefe, to think of throwing oft" the yoke of another <who fupplUs them nuith them, is an abfurd idea. This is precifely the cafe with our fugar idands. Let us fuppofe the continental colonies to be as happy in the necejjury agriculture as they really are, but to be abfolutely without manufactures, could the/ throw off theii allegiance \q Sritain be their numbers what they would ? No, certainly; Tor that is nothing mere than fuppc^fsng they fliould tlirovv oft' tlelr allegiance to Jjoas and fpades, and coats and y^-o^^, which is abfuiu io imagine : can any one imagine thai a rebellion can be carried on among a people, when the greatert fuccefs mud be attended with Ome lofj of ha!f the nece^aries of life ! •' TIi;U (he fhould abide by the boundaries fixed already totheolf'l colonie-;, that of the rivers heads; and ail farther fetdiug to be in kciv cclonies, wherever they were traced. * That fhe fhould keep the inland navigation of the contijient, that is, of all the great lakes and navigable fiver, to l.cifclf, and not fuifer any fets of men to navigate • " Tills point, which is of infinite importance, woiild prt'.ty fully be occafiiontd by other parts oi the plan, iiut, to cnfuic fo great a point, no new towns (L. iild lie fuiTtrcd, nor cvf n villages ; ihati \v!nch nothing could l)e eafur to manage : nor would they be any where ncccd'ary but by the inaga/incs ot naval (loics for loading fiiius. All pollible decrcafe ot numbers in ihe cities already in being, flioutd be ciretStcd. So fyflcmaticaMy abfurd is it "to iound towns nnd cities, as Britu'ui has iiithtno couftAUtly dofle, in all lUe iiolonie.'- ilic has fo;mcd.!' ** That fhe fhould thro»v whatever obftacles fhe could, upon all plans of commiini<.aticn from colony to colony, or conveniences of fpeedy removals from place to place. ' That in proportion as any colony di:'c1ined in ftaples and threatened not to be able to produce a fufficiency of them, the inhabitants Ihould receive fuch encouragement to leave it, as more than tc draio its natural increafe, unIcfs new ftaples were dilcovered for it. * This is non» the cafe with thofe I have diftinguifhed by the title of the northern colonies ; inio:n ich that Nova^ Scotia^ Canaduy Ni'VJ-England, Ne^v York, Ne-iv-Jer/ty, and Pewifylvania, would be nearly of as much benefit to this country buried in the ocean as they are at preient.'* The conduft of adminiftration correfponds exadlv with the fentiments of this modern writer, and with the mcafurea purfued by Philip the fecond oi Spain againft the tow Cmntries. The reafons given by one in adminillration for attacking the colonies, feem to be copi "d (with Tome fmall alterations on account of rtligion) from the famous advice of the unfeeling duke oi Alva, that** fpecie retinendae dignitatis," ccft his mailer, his glory, his happinefs, and his provirices — and funk his countiy into diiheflcs, fiom which ihc is not yet recovered. '* At vero dux Albanus arma & t;LTioNEM,contendebat, ««/V«/fl Isefx auctoritati principis iCmedium. Quippe ceteris artibus ac diuturna facilitate nihil aliud efFedum, quam uC regi obedieuiia, rebellibus timor Poflulafle^r/';f//^/(7 Belgas, ut Hifpanus c provincia miles exceJeret : id rdlicct unum declTe conllantes jid quiptem populorum. Num propteri.a, impetraia externo' rum ;/i/^;W quieviflc ? ^n potiui "v confideiuius efflngitafTe, ut— clrtvo detarbaretur GRAN VELLANUS. At unius forte naufragio complacatoi fuifle ver.tos. — Quin immout u'rgntia crefcit faciliiis — homines a nollra facilitate fecuri — UhelUsiit' rUiculis^ Jfagig/'ofs con/piratiof^iSus—improh'is palam carminibus — minis — precibus armatis — extorfercnt quod averent— o\i?iin3i\.i^inverecuncie legationibusHifpaniam fatigarent— ' Hicquoque vifumclementiae piincipis aliquaindignapofcenlcbus indulgerc. Enim vero quid ex ilia indul^eiaia relatum, nift ut vororum ubique compotes, non parcndo ; fubditct fefe oblivifcerentur, obfcqium dedifccrent, atque exuta principis reverentia, communicata provinciarom defeflione, tanqjam cuipa ibcieiate tutiorcs, humana omnia contredlatac femel libertati poft haberen!:. Nunc veto non uniut civita' iisy fed /rcy/fltit^rB.v/ a7»/^/?/a peccatum efTe in regem. Nee quia rebelles in prefcntia ccnquiefcant, minus ferociae animis incfle> refumpturos utique vires, ubi tnetum uhients abjecerint. Sic ;7/« pronus ad asperio'ia, difleiebat." Strada de bello Btlgico, lib. 6. It is evident, that the Britijh jninifters have diligently ftudied Straiia and the other authors who have tranfmitted to pofterity the pleafing and inilrudive annals o. Philippic po- ' licy, as every mcafure ihey have taken, is founded on a precedent f<;t by that celebrated fchool of hum.anity. diva is the favorite ma(kr-on his conduft they keep their eyes ftcadily and reverently fixed, and It may truly be faid — they follow him with no unequal ficps. Great, gcod, and wiVe men ! whom fome future Pujfenclorf or Tsmph will duely celebrate. * In i5<54, Granville was removed from the council, to appeafe the people. Their joy was fhorf; lived j for as the yiiwr meafur!;s were purfued; it foon began to be faid ^ublickly, that though his bodv was removed from, his /pirit flill iiitluenced the council, Uj.)on application for a relaxation of the edicts, it was fald, that modtration had tnly made matters ixjor/e, and the obrervation of thtm was again •njoined upon more fevere penaltits than befoic. ' At length an association was entered into, for mutually defending each other. This being figned by above 40^ perfons of quality, who all proieitcd, that they raeant nothing but til' honor of God, the glory ol the king, and the good ol their coun'ry, they met ajid PirrriONEi, that the praclamatian might be revoktd: but the king would confcnt to no mitigation. Good advice was given to him. But the duke /)V/v«'j violent counfel, who proposed the entire ABOLlSHMttNT OF TH2 LIBERTIES OP THE PIO- viNCKS wai moll pleafing and followed. The crt^el cuke was fent into the ioow Countries with a powerful army. The counts D^E^mont and Horn, were immediately feizedv on a pretence that they had underhand, fpirited up the people's difci^'eiiioH. They were afterwards executed. All who -Had figned the association or petition were declared guilty of \ HIGH TREASON, and anivverable for what had happened. A council called from its cruel proceedings, f THE COUNCIL OK BLOOD, was ereded for trying the accufed, from nvhich there nuas no appeal, (Note well) 41'wa himlclf tried the accufvd in their own country^ where their friendi and nxitnejjes might attend them, — where the paini of death itfelf might be mitigated, by feeing with their dying eyes, that they expired beloved and lamented. Here, the difciples exceed their tutor. This is too great a confolation to be indulged to a colorift. He mud be carried 3000 miles acrufs the ocean - that he may not only dye, but be infuUed in nis laft momenti, with the mockery of a trial where the clearelUnnocence Hands no chance of acquittal, tal, and with the formality of a fentenre founded on a (latute paft before the colonies cxiflcd.( 'r the approach of the army, the piiticc oi Orange and other lords fled; and being fummoneJ to appeal before the council, in default thereof were condemnv'd, and their eftates confifcatrd. ^/i/<i treated all, 'he innocent and ^«///v with fuch rigor, that it gave rife to the following facing of a Spaniih officer — ** Haeretici fraxcrunt . templa; btni nihil faxerunt contra: ergo omnes debent paiibuluri ' Sir WiUmmTempU\ account of the diilurbances in the Zoio Cohutriis agrees exadly with the foregoing extrafted out ol PuJfendorJ by which it will appear wi,.^ what a furprizing; exadnefs of refemblance the affairs of the colonics have bten carried on by adminlHration, " Jrhe war with France btii)g concluded, it was rcfolved to ke#p up the truops in theie provinces, and that the dates flioi^ld fupport them, which by a long courfe of war was giftwn cullomary." When Philip would have put Spanijh Mrrifjns into fome of their tovvus j and for tlie fiike of their admitting them quietly, gave the command to the Prince of Orange and Count Egmont : they told him plainly, " Thai all the brave llanos tney had made againft the power of France^ availed them but little, if they mull at lad be enllaved by another foreign power. Puf. ' The Matjed of the people, the infolence of the troops, with the charge of their fupport, made them looked upon bv the inhabitants in general, as the injirumtnts of their opprejjion and Jlaverv, and not of their defence, nvhen a general peace haa hft I hem ne enemies : And therefore the ftates bega I here their complaints, with a general confcnt and paflion of all the nobles, as well as towns and country. And upon the delays that were contrived or fell in, the ftates firft rcfufed to raife any more monies either for the Spaniards pay, or their own ftanding troops , and the i^eople ran into fb great {fr/pair, that in Zealand they abfolutely pave over the working at their dikes, suffering the sea to gain IVERV TIDE UPON THE COUNTRY, and ref(j]ving, as they faid, rather to be devoured by that element, than by the Spnnijh Ibldiers ; fo that at lall the king confented to their removal. Another grievance was the appointment of ^exu judges, * and thofe abfouitely depending on tlie king, S:c." ♦•Granville, lliamed up to the liij;hell hii mailer's authority and the execution of his commands, while the' provinces were refolute to prote61 the liberties of their country, againll the adniilTion of this new and arbitrary CUSTOMS OF THEIR co'jNTRY. The king at lail confePiied to Granville's recefs. Then all noife of <i'yco«/<'«/ and tumult was appeuJeiL But quickly after the Jame ccurfels were refumed. The d^fturbances then grew greater than hefore. But by the prudence and modeiation of the duichcfs of Farma, the governef', the whole eftate of the province* was reftorcd to its former peace. This durchsfs, and the duke of Firia, one of the chief minillers in Spain, thought and advifed, that the then present peace of the provinces OUGHT not to be invaded 3Y NEW OCCASIONS, nor the royal ajtliority leirenctl, by the icing being made a a parcv m a i j^on his fubj'ils. But the king- was imin«-vcable ; he :hed Jl^va into the Low Countr)- at uinier tlw- ijoawBaiU of the i>ejl tfjlcers, which the wars of ChaAa ymt ^xSx^ or PL'uf: the fecond h d bred up in Europe ; •k'-'h, with t-w6 tbjujand more in the provinces, under tWcoflMund of to old «nd renowned a general as the duke of Mnja, mad« up -a iorcc, which nothing in the lonjo CommbmK could look in t;e face with other eyes, than of aftonilhmcnt, rubmilHon or defpair. This power was for the a[lijlan(e of the gcvernejsy the execution cj the lazvs, the fupprtjjing and pumjhing ali wlio had been authors or foment' en oi' the late dtjiurbances. § On his ariival the governefi having obtained leave of the king, retired out of the province. The duke of Alva was inverted in the government, ixjithpoinjers nevtr before giien to any governor. A council, called THE COUNCIL OF BLOOD, \|\| w as erefled for the trial of ail crimes committed againfl the kirtg'i authority. The towns llomached the breach ok their chartbi^j, the people of their liberties, the knights of the golden fleece the charters of their order, by thefe new AND opious courts OF JUDICATURE ; all complain of ihe DISUSE OF THE STATES, f of the INTRODUCTION OP ARMIES, but all in vain. The king was conftant to what he had determined. Mva was in his nature fr/<#/and imxorahle^ The new army was fierce and brave, and defirous of nothing fo much as a rebellion in the country. The people were enraged, but awed and unhcadcd. All wa^ seizure ji.-oa and horror ;— insolence and dejection; — PUNISHMENTS cxccuted, and meditated revenge. The fmaller branches were lopt off a pace ; the great ones were longer a hewing down. Counli Foment and Horn lalled feveral months; but at length, in fpite of all their fervices to Charles the fifth, and to Philips as well as of their new merits in quieting of the provinces, and of fo great fupplications and interccffions as were made in' thtir favour, both in Spain and Flankers, they were jublicly bt headed at Briiffelst which fecmed to break all patience in the pcoj le ; and by their end to give thofe commotions a beginning, which coft Europe \o much blaod, and ^jfain a great part ot the Low Country provinces. The war begun, Alva had at fiding Jir/l great fucccfs. Moved with no rumors, terrified with no threats from a broken and unarmed people, and thinking no mea/ures or forms were any more ncctirary to be obfcrvcd in the provinces ; he pierends greater funis are iieceflary for \\it pay and reiuard oi hi ^'viiloricns troops than were annually GRANTED UPON' THE KINO's REC^'SST BY THE STATis or THE PROviNCbS '. (Nott. Hcrc OUT minillc. s have again improved upon Philipi\ ; for they have taxed us, ^vithout making req lelb.) § And therefjie demands a general tax of the hundredth part of every man's edatc, to be raifed at once : and for the future, the twentieth of all immoveable, and the eighteeiuh of all that was fold. The ftatcs with much relu,^ancy confent he firft, as a thing that ended at once. They pe i irix. • ^'^f^S dut wiracuT REDRESS J draw out the ye.tr in -ontells, fometimes llomachful, fometimes humble with the governor : Till the duke, impatient of delay, caufes the ^diV?, without cokSENT of th£ states, to hi publijbcd. The people ri" fuse to pay ; the soldiers begin to levy by force ; the townsmen all shut up THE^R shops; the peofle much as bread a-^d meat is to be bought iu the town. The duke is enraged ; calls the fzlUers to arms ; and commands feveral of the inhabitants, who refused the payments, to be hanged that very night upon their sign posti ; which moves not the obftinacy of th« pcop'e. And § Another advantage the Brr/i/^ minif^ers have over the Spanijh in depth ot policy, is very rcinarlcible. Spainrv/zt A gieac empire. The Low Coimtrics a mere Tpcck, comf v ri with it. Spain was not a maritime ftate that depended upon them for the fupply of her revenue. Had they been Unit in the Tea, flie would fcircely have felt the lofs. Her profpeCt of fuccefs was almoit certain. France, licr then inveterate enemy, cxhavifled by a civil war, and divided into two powerful pirtres. Every circumrtancc ii direiflly the revcrfe to Great- Britain m her preiient cotitcil with the coluuics. " Siquidcm vcriirimnm eft, ijnem tcvli-. iiiji^'cit', et iiijciflo fpatiufli moduniiia:. Sutucrs, coa ^.Ic m Cjufdem niaixu." wow THE OFPICltRS AND THE GUARDS ARE READY TO BLC3JN THE EXECUTIONS, w4ien ncvvs comer, to tovvn of the taking of the BriJt by the Cuefes, ff and of the expe£lation that had <^iven of a fudJcn revolt in the province of Hcllnna. ' This unexpci'^rd Wow struck the duke of ///i/^, and fortfecing the confequcmcs uf it, becauff he knew the ftubble was dry, and now he found the fire was fallen in, he thought it an ill time to make an end of the tragedy in lirabattt, whilft a new fccne was opened in IlollatjJ \ and fo giving over for the prefent his taxes and executions, applies his thoughts to the fuppreflion of this ne* enemy that broke in upon him fif^m the 0.a. And jtoiv began that great commo> tion in the Lonv Counf-ies, which /icver Cfw^cJhMi in the lofa •of lliofe provinces, when the death of the royal government £ave lifi to a new commonwealth." lands by fir hFiltiam Temple. Philip and his junto of cabinet minifters thought themfclves no doubt very wife, and politic as fo many Machiavels. But what Hu's, and will fay mankind as long as the memory of thofe events is preferved ? That their counfels were def icrrble, their motives deteftable, and their minds like thofe defcrib -d by the biihop of Lerida, that exadtly refemhled ihe hon.s of tSe cows in hia country — little, t Hooke", ' Ft^r a man to be tenant at '-will o{ his liberty 1 can nev«r agtee to it. It is a tenure, not to be found in all Litt'eton"' Speech of Sir Edvk^ard Coke. ♦" B/Tcr^rj — Tliev were cai'icd fo in fr>ntcmpt, when they peiiti'HcJ. ( hfr peoM. tiicrciipod ai^unud ihat name, peibap» tO kur;> ap liic mcmurv <:i£ an iufuU ouafwncd by their loyaUy. became the caufe of all men's mifcry," they generoufly fuffcred.---And the worthy bifhop before mentioned, who, for ftrcnuoufly aflfertinothe principles of the revolution, received the unufual honor of being recommended by a HOUSE OF COMMONS to the fovercign fur preferment, has juftly obferved, that " mijery is the fame whether it comes from the hands of many ' It could not appear tolerahk to him (meaning Mr. Hooker author of the ecclefMftical policy) to lodge in the governors o( any fociety an UNLIMITED AUTHORITY, to anull and alter the conftitution of the government, as they fhould fee fit, and to leave to the governed the privilege c«/y of ABSOLUTE subjection in all fuch alterations \ or to ufc the parliamentary phrafe, " in all cafes whatfoeverJ" [ From what fource can Great-Britain derive a fingle reafon to fupport her claim to fuch an enormous power? That it is confident with the laws of nature^ no reafonable rnan will prftend. That it contradidls the precepts of chrifiianity^ is evident. For fhe drives to force upon us, terms, which fiie would judge to be intolerably fevcre and cruel, if impofcd on herfelf. " Vir" tual reprefentation^* is too ridiculous to be regarded, ne neceffity of a /upreme fovereign legifla-- ture iiitcrn.Vily fupcrintcnding the whole empire, is a notion equally unjull and dangerous. ' 1 he pntence (fays Mr. juiUce Blackjlone fpeaking oi James the firft's reign)** for which arbitrary mealures was no other than the tyrants plea of the NECESSITY OF UNLIMITED POWERS, in works of evident utility to the -fpublic, the fupreme reafon above all realbns, which is the falvation of the king's lands and t With fuch fmoolh words may the mod dreadful dcfigns be gloflld over. " There arc feme men who call evil, good, and bitter, twcet.-^yujfice, is now called /o/wtarity And Fa Jlion.'* Pari. hill. 8. 193. '* A man fliall not unprofitably fpend his conicmpUtlon, that upon this occafion confiders the method of God'» judicc (a method terribly remarkable in many palfages, and upon mmy perfons, which we fhall be compelled to remember in this difcourfc) that the fame piinciplcs, and the fame application of thofe principles fliould be ufed to the wrcfting all fovereign power from the crown, which the crown had a little before made ufe of for the extending its authority, and power, btyonJ Ws hounds, to the prejudice of' ihejuji rights cfthf, fuhjeii. A supposed N£C»s«ity was then thought ground enough to create a power, and A BARE AVERMENT OF THAT NECESSITY to beget a practice to impoje ivhat tax they thought convenient upon the fubjedt, by writs of Jhp-mtiiiey never before known, and a fuppoled neceflity now, and a bare averment of that neceffity,. is as confidently, and more fatally, concluded a good ground to cxi;Iude the crown fiom the ufe of any power, by an ordinance never before heard of, and the fame maxim of " falui populi fuprema lex," which had been ufed to the infringing the liberty of the one, made uf« of for dellro) ing the rights of the other.'* Lord C/;##«<»'c//s hill, b. 5, p. 54, people.'* This was not the dodtrinc of James only. His Ton unhappily iniierited it from him. On this flimfy foundation was built the claim oi fiip money &c. Kor were tiiere wanting men, who could argue, from the couiily text, that parliaments were too fiupid or too faflious to grant money to the crown, when it was their . intereft and their duty to do fo. This argument however, ^^^ fully rctuted, and flcpt above a century in proper contempt, till the pofteriiy of thofe, who had overthrowii it, irougl.tfit to revive the exploded n-hfurdity. Trilling as the pretence was, yet it might much inorc propeily be urr .' :;-i 'ivour of a fingk fcrfov.^ than of a multtu.lt. /".ccounfcis of amonirch may be more <'^ciet. His mcafurcs more quick. In j^afllng an a£l of par' ^ment for all the colonies, as many men are tonfjitcd, if not more, than need be confulted, in o''taining the anfenr of every legiflaturc on the contin nt. \[ it i' ago argument for parliament, it is . better ag.iinli vliem. It therefore proves noihing but its own fi ilirv. The fuppojed advantages o\ fuch a powi-r, could never . L 2 fits, ■\ Thus the patriotr of Char/es^s days argued — "It is not, that ftjif-money hath been levied upon l'J, but it is, that thereby fhip-money f . -ned^ which is the gift and earnest PENNY OF ALL WK UAVE : it 15 fiot, »^hat our perrops have been imprifoned, 'u' .he payment of Inip money, but that our persons and lives are, upon \\\^ lame ground of lavj, delivered up to nvill and ^>leafure, his, that our //^, evidenced by fafls to cxifv without it. The Swifs Cantons^ and the United Provinces^ are combinations of independant dates. 1 he voice of each mud be given. The inftance of thefe colonies may be added: For dating the cafe, that no a<St of internal legiflation over them had ever been pad by Great-Britain^ her wifed ddtefmen would be perplexed to diew, that die or the colonies would have been Icfs flouridiing than ihey now are. What benefit^ fuch a pow<ir may produce hereafter, time will difcover. But the colonies are not dependant on Great-Britain^ it is faid, if fhe has not a fupreme unlimited legiflature over them. ' I would afi< thefe loyal fubjefls of the king (fays the author ot a celebrated invediveagaind us) J what king it is, they />r<?/>/} themfelves to be loyal fuhjeds of? It cannot be his prefent mod gracious majedy, George the third, king of Great Britain^ for his title is founded on an a£l of parliament, and they will not furely acknowledge that parliament can give them a king, which is of all others, the higheft ad of fovcreignty, when they deny it to have power to tax BIRTHRIGHT IS dcftroyed, and that there hath been an en- r deavour 10 reduce us to n lower Jiate than villainage, ThC; -. lord might tax his 'villain de haut et de hafle, might im- .-^ X See note on thefe words — " Therefore a power of re-^j^t gulating pur trade, involves not in it the idea of a fupreme legiflatur;^ over us." pa. 1 2 ^ or bind them in any other cafe ; and I do not recolkSI, that there is any adt of alT i;nbly, j[> any of the colonies for fettling the crown upon king ^tlliam or the illuftrious houfe of Ilaiiover ." " Curious reafoning this." § It :s to be wi(hed the gt-ntleman had ' utol'eCied' that without any fuch ' adl of allcmbly" none of the colonics ever rtrbclled. What aSf of parliament is here meant ? Surely not ^hc luh Ot Henry the leventh, chapter the id in favour • * The controierjy between Great -Britain and her colonies revie.ved." The learned gentleman who wrote this piece, has thought proper to quit his argument, rtep out of his way, perfonaliy abufe and leverely attack the wiictr of the " Farmer's L'-tters." His principal objedions are the Ibl'owinir, and the anfwers here given may perhaps be fuffi- ' cient to fliew with what force his objedions are geneially A urged, ifl. He fays, " the wi iter of the letters, tells us, chat the drawbacks A'hich aie illowed on fome articles upoai^' their exportation fro;^ England 2Lmo\xxiX. to more money than all the duties t0L;ether which are laid upon them on their ar- ^ rival in the colonies will produce. 1 believe it is the firft^f time that the colonies of any Itate have complained of the^^ injuftice of the m^ither country in laying taxes upon them, which were not fufficiently heavy y nor was it ever lefore dil- '^ covered that the proper means to redrefs the grievances of any people, were to increafe their taxes " Page i6. Anh-wer, .. .. The truth of the affertion in the letters is not denied. It is aflumed, by the author of the '* com. jverfy," as the foundarJ^^ tion of his argument. If then, parliament would have ^^ raifed more money, ' hjr flopping the drawbacks, than by,^^ laving the duties lobe paid in the colonies," nuhy were they kid ? From r^rfped for parliament it mull be fuppofed, x\kt^, were laid iot Jome purpofe. ' -^' ''~" ^~ '^ '" ~' ^'^ i 86 1 favour of a k\i\gdefa^o. Probably the 12th and 13th ot William the 3d chapter the 2d * for the further limitation of the crown &c.'* is intended. And, is it imagined that the words " dominions and territories thereunto * belonging" money. For what then ? To cfiablifh a precedint for taxing the colonics, fays the writer of ihe letters. The author of the controverfy does not deny it ; hut enters into a diflertatlon upon the more and the lefst which is not the point in queftion. 2dly. 1 he writer of the letters fays, that zci aS of parliament commanding us to to do a certain thing, if it ha: any validity, is a tax upon us, for the ex^' fince \\ that accrues in complying with it." In reply to this, the author of "the controverfy" enumerates many inftances of fovereignty Jubjeding the cclcnies to expince, which he fup■pofes may be legally exercifed within the colonies •• by ACT OF parliament". Pages 23, 24. Anj'wer. The propriety of this fuppofition is dcnitd, and remains to be proved. Abfurdities and contradictions" are pleniitully attributed to the writer of the letters, becaufe he will not acknowledge, that the power of parliament ** to regulate ^ trade, and prefervsi the connection of the whole empire in f" <iue order,' involves in it a power to " tax the colonies," or " to put them to any expence" parliament fl>all pleaft, ^ A perfon of fuch fagacity, as the author of the controver' {^t might plainly have perceived, if his refentment had not prejudiced his candor, that the writer of the letters, was unwilling to give up any point, which he then thought effential to the freedom and welfare of his country, and at ■j^D'tti II Thjj fcptcnce related to the diflblutlon of the aflcmbly of "f'f A rw- Tori, for not complying 'with the adl of parliament for not //-^vfupplying the troops. Laft feflion of parliament an adk was pafl'cd ,»;>;: for the more commodious quartering of the troop* in America. It is '13'! not yet come over ; but dcferves the attention of the coloaifts, even I 3 if it has not the remarkable features, that diftinguifli the prod uc^ rbi'tions of the laft fcffion. belonging' in that ftatute, form his majeily'a title to th" fovereignty of thefe colonies? The omiflion of them might have looked odd-, but what force is added by their infertion ? The fet-:- ^ ' tie men c the fame time was § unwilling to propofe any new fubjcifl of difpute. Jallly has the author of the controverfy obferved— that • it would be cndlefs to trace this dodrine of 3dly. The writer of the letters fays, we are as much dependant on Great -Britain, as a perfedly free people can be on another." On this the author of the controverfy kindly obferves, that — it is a pity the learned editor (the Eng^ lijh editor, it is fuppofed) his not given the public a differ■ '^ '' * ' tation § " If any pcrfon (hall imagine thit he difcovers, in thcfe Icitcrs, the Icaft diflik.' of the dependence of thcfe coloiiies on Great-Britain, I beg that fuch perfon will not form any judgment on particular exffefficns, but will conQder the tinor of all ihe letten takdn tc gether. In that cafe, I flatter myfclf, that every nnprejudiccd reader will be convinced, that the true intcrcfts of Great-Britain jirc as dear to me, as they ought to be to every good fubjeifl. pendence founded on mutual benefits, tlic continuance o^' wbichcan be fccured only by mutual afettions. Ihrrcforc it is, that wiih extreme apprchcnfion I view the fmatleft feeds of difcontent, which arc unwarily fcattered abroad. Fifty or Ji.xty years will make aftonifhtng alterations in thefe Colonies ; and this confidcration fhould render it the bufinefs of Great-Britain more and more to cultivate our good difpofitions towards her : But the misfortune is, that thofe ^r^fl/ mf«, who are wreftling for power at home, think themfelvcs very flightly intcrefted in the profpcriiy of their country fifty or fixty years hence, but are deeply concerned in blowing up a popular clamour for fuppofed »V«wer//fl/f advantages. •• For my part, I regard Great-Britain as a bulwark, happily fixed between thefe colonies and the powerful nations of Europe. That kingdom remaining fafe. we, Under its protection, enjoying pcace^ may diiFufe the bleliiogs of religion, fcience, and liberty, through remote wilderneffes. It is therefore incomeftably our duty, and our interejl, to fupport the ftrcngth of Great Britain. When confiding in that ftrength, (he begins to forget from whence it arofe, it will be an eafy thing to (hew the fource. She may readily be reminded of the loud alarm fprcad among her merchants and tkmcnt of the crown of England includes the fcultnirnt of the fovercignty of the colonics. K^ng PVilUam is mentioned — and will the gentleman venture to fay, that fniiiam was not, tarion on that mrft ingenious and inrtruinive pafiape." pa. it;. Anjiutr. Amtncan underftandings difcovcr no incOnfiftcncy in the idea of •* a Hate being dependant, and yet per* fe^ly free," and their temper is fo moderate that they would be content with that degree of freedom, which is compatible with a dcpendance. If the propofition puzzles B^ttijh underllandings, it is prefumed to be, becauie Briions will not give themfdves the trouble to think of any dcpendance, but of fuchy as is deftruflive of all freedom i though they themfelves are dependant in Tome meafurc on others. 4ly. The writer of the letters fays — ' if money be railed upon us by others without rur confent, for our defence, thofe who are the judges in levying it, mull alfo be -... . ■ •: , - .._ . jj,e " In the year 1 718, the Ruffians and Sivedcs entered into an agree mcnt, ntitto iuffer Great -Brilain to cxpoK any naval stores from their dominions but in Ruffian or Sivedijh fliips, and at their own prjces. Great-Britain was diArefled. Pitch and tar rofc to three founds a barrtl. At length (he thought of getting thefc articles from tlu- colonies ; and the attempt fcceeding, they fell down to fifteen Jiiillinjis. In the year 1756, Great-Britain was threatened with an inva/ion. An cadcrly wind blowing for tix weeks, (he could not MAN her fleet, and the whole nation was thrown into the uttnofl; confternation. The wind changed. The American fliips arrived. The fleet failed in ten or fifteen days. There are fomc other refle«aion», on this fubjedl, worthy of the moft deliberate attention of the BW/i^ parliament ; but they are of such A nature, that I do not chufe to mention them publicly. I thought it my duty, in the year 176$, while the ftamj>-ait \ris in fufpenfe, to wntc my fcntiments to a gentleman of great influence at home, who afterwards diftinguiflied himfelf, by efpoufing our caufe, in the debates concerning the repeal of that adV." Farmer's Letter, xii. p. 100, If the author of " tht controverly" had feen the letter above referred to, he would have found, that, the difi'ercnce between the PREROGATIVE in Great- Britain and in America, and the ei* ercife of imternal legislation by parliament over the colonies, with fome otiier points therein mentioned, were reprefented in the ftfonseft tcim> the writer of the letters could ufe, as unjuftj. king of England 2in6. foyereign of thcfc colonies,' before his tiile wa,. " declared" or " recognized" by '' an adl of parliament?" The gentleman flurs over this cafe. His zeal for the , '» M " illuftrious f aid lo be taken from us for our defence, may be employed^ to our injury. We may be * chained in by a line of fortifications— obliged to pay for the building and maintaining them — and be told that they are for our dt;fence ] With what face can we difpute the fad after having gr.ntf'd tliat thofe who apply the monev, had a right to levy it ? For (urely ic is much eafier for their wifdom to undcrlland how 19 apply it in the bell manner than how to levy it in the bert manner. Befidc the right of K.vying is of infinitely more confequence than that of applying. '\ lie people q{ England^ who would burft out into fury if the crown fhould attempt to //•vy money by its own authority, have always afligned to the crown the a'plication of money." From thefe words relating to " application" the author of ** the controverfy" deduce-^ a ' proof," that the writer of the letters is very deficient in " his knowledge of the conflitu and certainly tending ift a few years to produce thcdccpcft dJfcon* )- ' tents. The time is at lengilt come, when filence ia ^;Nfr(C(a on thefc fubjedls wou'd be Hupid ^r ciiminal. • The probability of this nieafurc taking place, is confirme4 by the Canada bill, a political device fo extraordinary, as to ex')'. ciicfurprize even in thofe colonics who live in the year 1774. By ' this bill, it is faid, the Itgijlativc power is lodged in the gorerno? and a few men, not Icfs than 17 nor more than 3, appointed and rcmoveable by the crown ; and the government becomes wholly ftored, and all the country on the back of these oo»m'' LUNiES is added to Canada, and put under the same m UNITARY government. This is indet-d to be '• citmed'm." No-is thing is wanting to complete the plan, but oiu money, to defray^f;* the expence of eredting jlrong hnlds among our woods .and mcii^e^n tains, and to bribe our Indians; and then the exprcfliQa of '• beat'->^c, trig our f-words into plough'jhares will be rcvcrfed in.ao extraordinary! ^ manner; for" our plough-thare" will furniftj tl.C very •' fwotds" that are to cut our own throats. houles i:on"t &c Aiif'wtr. Is this treatment generous? In fuch queftions ought the attack, to be turned from the cauje to the 7:ian ? The writer of the letters, pretends not to be diiHnguifhed, as a ** critic on government" nor for •• juftnels or elegance of compofrion." \|\| Surely, even the author of ♦* the controverfy " mull now be convinced of his averfion, to writing, as that performance, with all ♦ the jullnefs and elegance of its compofition, knowledgeof the fubjed handled, & confli tutional learning difplayed in it," and employed to pull to pieces the reputation of the writer of the letters, has not rouzed him during fo many years fince its publication, to make a finglc effort in vindication of his charafter. Was it imagined, that every objeftion was juil, becaufe not replied to ? Many reafons, befides a fear of encountering objections, may prevent an anfwer. In truth, he cannot be called a 'vclunteer author. — He never did, and never d\kzq to writt, but ivben the honour or interellof his country was alTaulted — when duty compelled every one to contribute what afTillance he could in her defence — and when he hoped, the caufe would draw fome kind of a veil over his defe(^ls. He expeded, he might efcape as the Spartan youth did, with fome flight cenfure for engaging improperly armed^ but that his motive would excufe him from a fevere one. How well founded the prefent reproach is, will now be conildered. One would imagine, that a man of common fenfe on reading the foregoing extrad from the letters, would underftand the writer plainly to mean by •* levying^* the power of** taxing* — and by ' applying* the power of ' employing^' x\ic money railed by taxing; or in other terms, i\ie uc'tual expenditure o£ it. This meaning is evident — the conclufion being expre/s, that ' i^ ethers may be judges in ap' flyifig money, ofconsuquence hmay ie employed to our in^^ jufy"— and then follow fome itijiancest in which it '* may Jo employed." All this is very clear. - How then docs the very ingenious gentleman open his way to the wiircr cf the letters, to give him this violent blov ? By a dexterity worthy of imitation — if jujlijiahle. He le.i'vcs out of his quotation, all the 'Words incloi'ed within the lall crotchet, beginning at the words " of coNSEquENCu" and ending at the words ' our def:nce," that Jhe'iued bevond a poffibility of doubt tn<vjhai jen/e the word ' apflyin^'' was ufed - lakes no notice of the Oiniflii»n— impofes another fenfe on the word —and then iiifuits, may it be faid, over the fuppofed millakc of faying, * that the people of £«j/««^ have always aflignecl to the crown the application of money." What fenfe he or others may afiign to the word ** application" is not the point: but whether the word, taken in that fenfe which the writer of the letters exprefsly annexed to ity is ufcd ijoith propriety by him, or whether it is ufed /;/ fuch a manner i as to ' prove he is very deficient in his knowledge of the conftitutiou/"' By that word, as he defines it, politively as language can declare any meaning, he intends, the a^ual expenditure and * employment" of moneys And is the reader to be tricked out ot that defnition, and ^?;;other /"enje f[\\i9^cd\nf merely to impeach a majtis charaftcr by flight of pen f Has not the conftitution " affigned to the crown the aC' tual expenditure and employment of money ?'* Is not this power part of the ^;r^^a//i;^ r" Does not Mr. juftlce Blackfone mention this power to fliew the V2<> ''nfiuence of the crown? — He particularly takes notice of it with refpe£t to the army — in thefe expreffions — • paid indeed ultimately by the people, but immediately by the crown ; rulfed by the crown ; officered by the crown; commanded by the crown."* "■ word to mean the Je/ignation of money to particular purpofes in a£ls of parliament. Could it be poflible, that^he author of ** the controverfy" (hould iinagiiie, the writer of the letters could be ignorant of fuch defignation or appropriation of money by parliament, when one can fcarcely open a book of ftatutes, without obierving them ? Parliaxnen; may accommodate grants of money to public neccflities — and may call officers of the crown to account for money, but thele powers no more prove the a£2ual expend'turt and employment of money to belong to parliament, than the power of calling officers of the crown to account for injurious leagues, or declarations of war, proves the power of parliament to make leagues or to declare war. fiefides, it being contended againfl the colonies, that the •' fovereign fower'* is lodged in king, lords, and commons, the fame perfons may tax and expend^ to what excefs and in what manner they please, while the colonies will have no kind OF CONTROUL ovcr them : And, that fuch an union of thofe powers, is unconlUtutional and dangerous to the colonies in extreme, was the point the writer of the letter i^offenfively tn. ventured to yfift on. : ;j,,i' > -., Exadly in the fenfe here contended for, are the words ** appropriation" and " application' ufed in fome of the befl authorities. Bilhop EUjs in his trads on liberty, page ^31, fays—" The parliament, at prefent, in granting money does for the moll part appropriate it to particular fervices, wheieby the application of it is more effedually fe.cured." ' When any aids are given, the commons only -.do judge of the neceffities of the crown, which cannot be \ Otherwife made manifeft to them, than hy inquiring^ Jiow the money which hath been granted, and re^^enue of the «rown, is expended and applied. ''"'^ ** Out of the aids given by parliament, (which by the law of England are appropri- tion of a king by the two houfcs, or to the limitation of the crown by ad of pirliamcnt, proves a right in parliament to bind the colonies by ilatutes " in all cafes whatfutrver." In fuch great points, the coiidudl of a people is influenced Jalely by a regard for their freedom and audi and ou^^ht to have been employed m the common profit of the whole realm) many la>gt fums of money, during the times of fuch heavy taxes uponilie people, have been diverted under the head Qi fecretferviceit and for JalatieSf lounties aiid ptnfions Sec."* Some other unfairnefles there are in this famous piece, that need only be viewed, to be refuted ; but of which, it may be faid, if a precedent" elUWidicd by the ref^etSlable gentleman himfclf, can procure pardon for the expreffxon, that" they are not entitled to notice." How could he venture to aifert as he does, that — the purpose ot the letters was to excite refentirent in the colonies aghinil their parent country and to pulh them on to a fepari^.tion from her." The letters prove the contrary Few men have expreft a warmer zeal for the connexion, than the writer of them 1 Yet his reputation is to be attac'.ced on every account, and a charge even ol dijloyalty direclly levelled againft him. The author is welcome to take what other licenfes he pleafes ia his reprehenfions of the writer ; but he ought not to have denied his integrity. Their inientions mull ftand the teft of a tribunal, that decides for eternity. May they then appear equally pure. ^ .?-,, True indeed are thofe words of lord C^»'^»</o//.— ' Let •'O Iioneft man that is once entered into the lifts, think, he can by any flcill or compo'iment, prevent theft conllifts and affaults — but let him.look upon it as a popatoy he is unavoidably to pafs through; and conflamly performing the duties of juftice^ integrity and uprightnefs^ depend upon PROVIDENCE, and time, for a vindication." Iiappinefs. The colonies have nootfier head than the king of En^hnd. Tht perfon who by the laws of that realm, is king of that realm, is our king. • A DEPENDANCE * on thc crown and parliament of 6V^rt/-/?//Vrt/>/, is a novelty- -a dreadful novelty. It may be compared to the engine invented by the Creeks for the dcftruflion ot Troy]'. It is full of armed enemies, and the walls of thc conltitution mull be thrown down, before it can bfe infoduced among us. When it is confidered that the king as king of England has a power in making laws- -the "powev oi exscuiif!g them- -of Jin ally determining on appeals— of calling jpon us for fupplies in '; * This word " d'^pendance" as applied to the Hates connefted with EuglanJ, feemi to be a new one. It appears to have been introduced into the language of the law, by the common wealth a£l of 1650. A • dependance on parliament" is dill more modern. A people cannot be too cautious in guarding againft fuch innovations. • The credentials of the imperial ambafladors to the ftates of Holland, were direded--** to our faithful and beloved." The words feem to be very kind; but the cautious ftates difcovered that this was the Aileof the imperial chancery in writing; to the 'vajfals of the empire. The queftion was, whether the credentials fhould be opened? and it was urged, that a folemn embaiTy ought not to be difappointed, for a few tiifling words. But the ftates refolvcd to fend them back unopened, which they did. Other credentials were then fent, w'th a proper diredion; and the ambafladors were well r eived." Arcana imp. det. p. 196, , ^f 7 Co. J 8, »••; times of war or any emergency— that every branch of the prerogative binds us, as the fubjcfls are bound thereby in En^Lwd—and that all our i n tercou r fe with /cr«^y;jri is regulated by parliament. — Colonills may " furely" be acknowledged to fpcak with truth, and prcciflion , in anfwcr to the " elegantly'* exprcft queftion— " What king it is" &;c. by faying that " his mod gracious iT\B.}t([y George the third" is the king of England^ and therefore, " the kir/g" they— proicfs themfclves to be loyal ftibjetlsofr . :'/ •" t'l We are aware of the objeAion, that, " if the king 0^ England is therefore king of thecolonies, they are fubjedl to the general legiflative authority of that kingdom." The premifes by no means warrant this conclufion. It is built on a mere fuppofition, that, the colonies are thereby acknowledged to be within the realm, and on an incantation expe6ted to be wrought by fome magic force in thofe woods. To be fubordinately conneded with England, the. colonics have contracted. To be fubjedt to the general legiflative authority Oi" rhat kingdom, they never contratled. Such a power as may be necefiary to preferve this connexion Ihe has. The authority .of i\\t Sovereign, and the authority of controulingour intercourfe Wiih foreign nations form that power. Such a pozvsr leaves the colonies free. But a general ler^iflativc power, is not a power to prefrrve that conne6lion, but to diftrefs and cnflave them. If the firft power cannot fubfiflr, without the laft, (he has no righteven to the firft, —the colonies were deceived in their contradt— and the power muft be unjuft and illegal; for God has given to them a better ri^bt to preferve their liberty, than to her to dellroy it. In other words, fuppofing, king, lords and commons ading in parliament, conftiiuteayi>t;^m^»/jf over the colonies, is that fovereignty conitiiutionally ahfolitte or limited? That ftates without, freedom, fhoukl by principle grow out of a free ftate, is as impolFible, as that fparrows, Ihould be produced from the eggs of an eogle. The fovereignty over the colonies, muft be * limited. Hejiod long fince faid, " half is better than the whole i" and the faying never was more juftly applicable, than on the prcfent occafion. Had the unhappy Charles remembered and regarded it, his private virtues might long have adorned a throne, from which his public meafores precipitated him in blood. To argue on this fubjed from other inftances of parliamentary power, is ihifting the Nee REGiBus infinha aut libera poteflast was the conftitution of our G/rm^a anceflors on the continentp and this is not only confonant to the principled of nature, of i^iBERTY, of REASON, and of SOCIETY, but hat always been eftcemed an exprefs part of the com.jc. x law of Englandy even when prerogati've ivas at the higbtji." 1 Blackft. 233. ground. The connexion of the colonies with En^landy is a point of an unprecedented and delicate nature. It can be compared to no other tafe; and to receive a juft determination, it murt be confidered with reference to its own peculiar circumftances. f The common law ex- f The learned Judge, [in Vol. i. pag. 107.] fays thi$ country was not • uftinhabiied when difco^er'^d and planted by the Englifh, &c. but ought to he confidered as a conqu^redt ceded, or infidel country. Our American plantations ^xt principally of this latter fort, being obtained in the laft century, either by right oi coi^que/i and dri^ving out the natives (with what natural juHice, I fhall not at prefent inquire) or by trtaties : and therefore the common law of England, as fucii, has no allowance or authority there, they being no part of the mother country, but diftindt (though dependent) dominions. They are fubjedl however to the cojitroul of the parliament.' , According to this do^rine, the colonifts are confidered in a legal vieixj by the parent ftate, ' as infideh or conquered people y not as her cnildren with her confent eftablifhing focieties for her benefit. Though not a fingle man of the infidels or conquered" people, fhould now be found to reiide in each col<;ny j yet a political contagion is communicated to Englijhmen in fecula ficulorunit becaufe /«dians once fiihed in the rivers, and hunted in the woods. If this be their condition,^' then according to the law laid down by the judge, they are fubjert not only to the contro).! of parliament y but the Kinj^ may alter and impoje what laws he piea/es." ^ It is not known, what the learned Judge means by the word principally.^* Perhaps he alludes to the '11 direded humanity and jujiice of the firft fettlers of fome colonies, who purchafed the lands from the natives, for valuable a;id fatisfaftory confideriitions. It was a very ufelelefs exercife of their virtues, for their pofterity. If they had hy accident fettled an. " uHtnhabited" country, the invaluable rights ' of the common law wduld have attended them ; but when hey dared to obtain a fettlemcnt by humanity and jujiice, they J orfeited all rights of the common law, to the Jateft ioccccdir.^ ages. Can this be /aav F Every cafe quoted by the Judge, it is humbly apprehended, makes a dillinc- ■ thri/lian poj/ej/hrs and OKvners by fair purchajes from thofe lubo '^ad a right to felly A £ at the infidels no longei pofjejjing or oivningy feems to involve a confufion of ideas, little agreeing with the ilrength of reafon that informs the common law. it is very remarkable, how our ablell antagonifts are perplexed in framing iheir arguments againft us. Even the learned judge does not exprefs himfelf with his ufual perfpicuity : But the want of it is well atoned, if we, colonics, can be thereby deprived of the benefits of the common lanvy and beabfolutely lubjeftedto the>f/«f ; for /^(f/ic6urtly tenets are the only confequences deducible from the cuiious argif~ vient ihat tends to involve thefe colonies in the misfortunes of if^ conquered^ cededy or infidel countries. " The * contrcul of parliament," is aflerted to be fupreme, in P'.\.ry cafe. Whether the colonies were fettled in " uninhabited countries," or in -? conquered, ceded, or infidel counties," makes no differenB€-as to that point. ..-Another learned gentleman has difcovered, that we " are iiiQt entitled to as great a degree of freedom as Ireland.** Why ? '* Becaufe Ireland was a ctnqnered country." This remark does not feem to remove the difficulty. Let us hear the point a litlle more explained, " Inland \\ is true was conquered, but certain conr.ejjiom were rradf^to the people. > Thefe were the terms granted therrij bot Eniland is obliged to keep no terms with the colonills." At every ftep theftt fventlemen take, thofe writers, who have contributed fo much to ihe ^lory of their country, turn upon them, and dircdiy oppofe them. Thev at firfl fhrink before thefe venerable advocates f)r liberty and humanity — but recolledlin^ themielves, they diltinguifh and refine, in order to take away the fubftance of every argument, and to whittle down a Hooker and a Locke into a Lejlrange and a Filmer. After taking thefe liberties, they at length grow bo'.d enough to arraign the authority of any man, even Mr. Lockn himfelf, if his writings cannot, by ail this art, be turned to their purpofe. We need not bt; furprifed after this, that every colonifl, who ventures honeflly, to allert, as well as he can, the caufe Ct his native land, Ihould be treated with little refped. The colonies, have always been on the defenfi<ve. It is HoyED THE Y WILL ALWAYS CONTINUE SO. But the author of ** the ' controverfy" charges them with great cunning, a left handed wifdom, that muft difgrace any people — becaufe they have not refilled, in places where they were not immediately attacked. ' It is the artifice of the managers, on the part of the colonies, to avoid ^^«^rfl/queltions, and to keep back and conceal confequences, leall the unfufpeding people of England ^osAA too foon catch the alarm, and refolve to withitand their firft attempts at independency. "jj That is — they have arted jult as the '• unfufpeding people of England" have done in their controverlies with the crown. T^ey confined themfelves from time to time, to a demand of redrefs, for the injuries offered them. This behaviour of the colonills, would, by forae perfons, be deemed modell and refpedful. Now indeed the condud of adminiilration demonilrates force." If even the common law, in force within the realm of England when the colonills quitted it, is thus abridged by the peculiar circumftances ot colonies, at leafl equally iufl, and Gonftitutional is it, that the power of making NEW LAWS within the realm of England, fhould be abiidgcd with refi cdt to colonies, by thofe peculiar circumftances. J The to us, that we muft enlarge our views, and cndeavourto take a profpeft of all the mifchiefs necefTarily attending a claim of boundlefs power with an unbounded inclination to exercife it. The gentleman may perhaps call for fire and faggots to extirpate our political herefy ; but we truft, and truil /irfn/y , that, the fenfeand generofity of the good peopl«of England, will difcovcr and defeat the prefent plan agaiiiit /^«r liberties, as they have already fo many other fchemes of that tendency— that they will behold their dutiful children with compafljonatc love, and with juft indignation thofe unrelenting enemies, from whom they can exped no other favor, themlclvcs aient, reaches only thofe who will take it on that con dition, and fo is no natural tic or engagement, bat a " voluntary fubnnflion; for every man's children being by nature as free as himleif, or any of his anceftors ever were, may, whilft they are in that freedom, choofc what fociety they will join themfelves to, what commonwealth they will put themfelves under; but if they will enjoy the inheritance of their anceilors, they muil take it " on the fame teims their anceftors had it, and fubmit la all the conditions annexed to fuch a pofreflion." Whoever (fays he in another place) by inheritance, purchafe, permiffion, or othcrways, enjoys any pare of the lands /3 annexed to, and under the government of, that • common-wealth, muft take it with the condition it is un• der; that is, offubmitting to the government of the . commonwealth under whofc jurifdidion it is, as far, forth as any fubje£l of it.'' page 31 The ingenuity of the gentleman is here again remarkable Mr Locie'm his a^th chapter on civil government ** Of the beginning of ^ political foci<^ties," immediatly before the words abovemen! tioned •* Whoever by inheritance," &c. fpeaks of a man ' who '* unites his perfon which was before iict to a fociety for the Jtatring and regulating of property, and fubmits to ■' the community thofe pofltJflions which he has or <hall acquire, that do not already belong to any other government." Thefe words the gentleman not thinking quite to his purpofe tn this place f feparates from the words of his quotation, and fo gives Mr. Lockers conclufion without his premitTes. However three pages after, he is fo candid, as to give the premifles without the conclufion. How, or why ? Jo fup'-'- poit this moft curious dillindtion,— that Mr. Zu-i^, in that ' i. celebrated part of his argument where fpeaking of" go•^'»s vernment taking the property of fubjeds," he fays "What no more* than that the fuprcme legiflative power has no right to take the property of others vvithout their confent " for the PRIVATE use or purpose of the Icgiflative." So that according to this conflruftion, the conftitution of a Hi" well eftablilhed governnacnt, or the freedom of a people, depends not or the great right which God has given them ' of having a fliare in the government of therafelvcs," whereby their property is fecured, but merely, on the * purpo/e," to which the property taken from them without their confent is «////<?</ by thofe who thus take it. And ^ yet this gentleman has fevePely attacked the writer of the letters, for ufing the word ** purfofe* in a much mere cott' Jint^kvikt in l«'i)ing. a ' tax is an impofition on the fubjed for i\\e /ole purpoje 0¥ levying money." ■'» " •'"'' narchy ("ays, • thatabfolute power purifies not mens bloods. For if it be aflced what fecurity or fence arifes infuchajiate, againll the violence and opprtlfion of ' the ai/olute ruler? the very qucftion can fcarce be borne. They are ready to tell you it deferves death, only to afk after fafcty. Betwixt I5ji fubjeft and fubjedl they will grant there mud be meafures, laws and judges for their mutual peace and fecurity : But as ioT the ruler, he ought to be ahjolute, and is abcve allfuch circumjlancei ; becaufe he has power to do more hurt and wrong, 'tis right when he does it. To afk how you can be guarded from harm or injury on that fide^ where the ftrongeft hard is to do it, is prcfently the voice of y<2c.7/o» and rebellion? But here our opponent may come in with another diftinAion. ** Mr. Locke fpeaks here of an ahfolute ruler, not q{ abfolute rulers. Lilly proves that there is the fingular number, and the plural number. A regard for that grand objedl ['■^r' held legal in the fcur hujidred o? Athens^ or the parliament of Great Britain'' Let the diflindtion be allowed its due weight. Can it be believed that fuch a friend to mankind, as Mr. Locke \vn%t could ever think ^//yo/z//^ dominion J juft or legal? Would not fuch a fentiment diredly oppofe thofe principles, his benevolence 'udi'ced him to take fo much pains to vindicate and ellablifh ? Would the found of the words — • dependance — " '• fubordination — " ** withirt the realm — " ' part of the dominions — " &c. have convinced him, that it was • the indii'penfable duty of parliament to eafe the gentry and people o^ Great -Britain by taxing the colonilh without their confent?" — and that it was the indifpenfable duty of the colonirts on conjiituiional princir pies to fubmit to fuch taxation ? The learned fay that the too rigid attention of the mind to one idea fometimes is the caufe of ma inefs. So rigid has been the attention of many heads in Great- Britain to the idea of dcpenhance^ that it feems to have cccafioned a kind of infanity in them j and by ruminating, fpeechifying, and enabling about it and about it, they have loft all ideas of jullice, humanity, law and conftitntion, and in fhort of every quality that ufed tp dillinguirti men from the reft of this creation, zxi^ Englijhmen from the reft of mankind. But Mr. Locke* % underHanding, even in the prefent whirl of the political world, would have preferved him, juft and tenacious of his princi* pies. The cafe he puts, and on which the author of • the controverfy" argues, is that of a fubmljfion to the arms of government in a common-nveallb. The queftion between Great-Britain and the colonies, is, ivhat are the terms of their connexion under all the circumftances of it. peiually animates the conftitution, and regulates all its movements— unlels unnatural ob(Irudions interfere-— " ' 'i-u.'-ih miht"^/' Ireland by ftatutes, ' in all cafet nKhatfwver .** Yet tlierii was in his time a famous dii'pute concerning the authority of parliament over that kingdom. So far was he from favouring the claim of parliament, tliai it is hoped, it can clearly be proved, he favoured the oiher fide of the quellion. His fiiend Mr, Molineux, in a letter dated Marc/? ij, i'S(,7-8, tells him of his intentions to vifit him--~when he coold gel loofe from bufincfs : ' But this I cannot hope for till the parliament in England rifes. 1 fhould be glad to know from you when that is expeifled, for indeed they bear very hard upon us in heland. How juftly they can bind us, <wuhcut our conjent and reprejentati'ves, I leave the author ©f the two treatifes on government to confider" — meaning on civil government; tho' they are publilhed alfo as one. treatife, the firft book of which is under the firil title, and the fecond book under the fecond title. „.. ,, Mr. Loch, in his anfwer dated April f^ 1698, fays, ' amongft other things I would be glad to talk with you about, before I die, is that which you fuggeft at the bottom t)f the firil page of your letter. I am mightily concerned for the place meant in the queftion you fay you will afk the author of the treatife you mention, and <wijh extremely luell to it, and would be very glad to be informed by you ijuhat "-Mould be bejl for it, and debate with you the way to compofc it: But this cannot be done by letters; the fubjefl is of too gr(;a( extent, the views too lar^e and the particulars too ^, Another argument for the extravagant power of internal legiflation over us rcmains. It lias been urged with great warmth againft us, that" precedents'"* fliew this power is rightfully veiled in parliament. SuBMissio?^ to unjufl fentenccs proves not a right to pafs them. Carelefsnefs or regard for the peace and welfare of the community, may caufe the fubmilTion. SubmifTion may fomerimes be a lefs evil than oppofition, and therefore a duty. In fuch cafes, it is a fubmifTion to the divine authority^ which forbids us to injure our country j not to the offiimed authority^ oh which the unjuft fcntences were founded. But when fubmiflion becomes inconfident with and deftru6live of the public gocd^ the fame veneration for and duty to the divine anther ity^ commands us to oppofc. The all wife Creator of man imprefb certain laws on Ills narurc. They were not intended to deftroy, but to fupport each other Man has therefore <i manytobefo managed. Come r-&^r^r# yourfelf, and torn* as luell prepared ai you can. But if you talk with others on that point there, mention not me to any body on that fuhjeS ; only Xtiyou and / try luhat goodnvt can do for thofe luhom nvi nxnjb nvell to\ great things have fometimcs been brought about from fmall beginnings nuelt laid together ^ right to promote the ^/?/? union of both, in order to enjoy both in the higheft degree. Thus, while this right is properly excrcilbd, dcfires, that feem felfijh^ by a happy combination, produce the welfare of others, " This is removing fubmiflion from a foundation unable to fupport it, and injuriousto the honor of God, and fixing it upon much firmer ground."* No fenfible or good man ever fufpcded Mr. Hooker of being a weak ovfatUous perfon, " yet he plainly enough teacheth, that a fociety upon experience of univerfal evil, have a right to try by another form to anfwer more effetoally the ends of government" — And Mr. ^oadley afks — ' Would the ends of government be deftroyed fhould the mifcrable condition of the people of France^ which hath proceeded FROM THE king's BEIiVG ABSOLUTE, awaken the thoughts of the wifeft heads ay^ mongft them ; and move them all to exert themfelves, fo as that thofe ends fhould be better anfwered for the time to come ?" able — tliat is, that precedents that ought never to liavc been fct, yet being fct, repeal tlie eternal laws of natural jullice, humanity and equity. The argument from precedents begins unAuckily for its advocates. The frfl produced againit us by the gentleman before mentioned, was an a6l palled by the Commonwealth parlia- A mortals law of power or ftrength fufficient ♦« To abrogate the unwritten law divine. Immutable, eternal, n t like thefe Qi ycjhrday^ but made e'er time began." ^. ,^ Sophocles's Antig, Frank, TratiJI. ' "It (hould be confidered, whether it ever was or ever can be the true incereft of a kingdom or (late to violate the laws of natural juflice, equity and humanity. Thefe laws may be called the laws of God. Can they be broken with impunity ? The fcriptures arc full of leffons on this fubjeit, and hiftory furnilhes inftances fufficient to alarihoppreflbrs, if they would atiend to them. All the glories of Charlesthe hold,— C /jar ks the fifth, — P/jiIi/> the fecond, — Charles the twelfth, — Lezvis the fourteentii, — and a numerous lift of diftinguilhed princes, were overcall, when unrelenting cruelty came to prelide over their refolutions. From Athens to Genoa the obfervation holds true. Let not the opiniort be condemned as prcfumptuous, before it be fully enquired into. It is worth an enquiry. ^'^'^Wer^! in 1650 to " pitnilh' yir^inia f, BarliaJos^ f\^i^^j4ritfgua^ and Bermudas, for tiieir FiDBLnv 2'jjnij.Q Charles the Second. .9y mitieni is the Miy.,V/??/ of parliament to * puniJJj' ( olonills for ^' dbittg their dut). But tlie parliament had before overturned church and throne^ fo that there is ^ an older precedent ^"et againil thefe. <'•'"? * gal one. The Revolution fucceeded, and v/it!i r it methods for blending together the powers of ' king and people in a manner before unknown. • A new political alembic was fixed on the great . principle of refiftance, and in it, feverc experiments were to be made on every other principle of the conftitution. Hov/ the holdnefs of mini- fro f' This loyal, generous colony pre&rved its principles ^ith Aich fpirit, notwithllanding the oppreflion abovemen. tioned, ii^^xxn January 1659, they threw ofFall obedience "" to the parliament, replaced the kings governor, and proclaimed Cbarlts the fecond, feveial munths before the rcllo- ■ racio^i yn £«r(>/^ * .. , ' t ,1 fters & eontempi of the people have liirrcafcd fincc V that pcno.i, n:)t a man the Icalt ucijuaiiital with .)\ En^lijh \\\[\oxy can be ifrnorant. '1 he Colonics were in a (late of infai)cy — Hill in a Hate of chikU , hooil. Not a fuiy;lc Itatutt' conccrninjy them ir. recollcdetl to h^ve been pall b';fc)r<? the Revolution, buc fuch as relatevl to tlv.* re«:ulation of trade. " Precedence" v/ere afterwards mad<?, that, wli'jn they ^?;rew u^"), the authority of a fmfier mi2;ht fuccjed thr.: of a/'.7r^;;/.'''^'nij\|t •y ■ Pri:c:::)i:>jtc;, it h apprehended, arc noother. wife regarded in th.e Eh'jUI!} laws than as they , eitabiilh certainty for the dunefit of thb I'EOPLi: — according to the maxim — " niiferable , is the fervitude when the laws are uncerfain.** > Precedents militating again(l,the v/elfare or happinefsof a people, areinconfiltcnt with tTie grand original principle on v/hich they ouglic to be founded. 'I'heir fuppofcLl fancLion encrcafes in proportion to the repetiticnj of inJAifhice. They , muil be void. In fiibjcit.] of dif\|.)ute between man and man, precedent may be. of ufc, though ^ not founded on the bell reafon. Tiiey caufe a certainty, and all may govern themfelves accordingly. If they take from an individual one . day, they may give lo him i\v^. ne::t. But pre/^cedents to oY^nhco^N principles, to juitify tlie^^r/>f/«^/ opprefiion of/?//, and to impmr tb: power of the covjliiutioHy r]iough-a cloud of rhem ap- L 110 J pear, have no more force than the volumes of diift :hat furround a triumphal car. They may obfcure it : They cannot (lop it. What would the liberties of the people of England have been at this time, if precedents could have made laws inconfiftent with the conftitution ? Precedents tending to make men unhappy, can with pro-priety of chara6t:er be quoted only by thofc beings, to whom the mifery of men is a delight. " If the ufage had been immemorial and uniform, and ten thoufand inftances could have been produced, it ^yould not have been fufficicnt ; becaufe the practice muft likewife be agreeable to the principles of the law^ * in order to be good : whereas this is a practice inconfiftent with, and in dired oppofition to the frji and cleareft principles of the law" ■\ — to thofe^Wings of humanity^ out of v/hich mankind will not be reafoned, when power advances with gigantic ftrides tnreatening difiblution to a ftate — to thofe inherent though latent powers of fociety^ which no climate^ \\ no time^ no conftitution^ no (ontra5iy can ever defti oy or diminilh." J '^ ' * ■ A PARLIAMENTARY powcF of internal legijlaHon over thcfe colonies, appears therefore to us, equally contradidory to humanity and the cortftitution, and illegal. " ''''''' *" ... .^...^.u^i . . As to the fecond head, a power of regulating oiir trade, our opinion is, that it is legally veiled in parliament, not as a fupreme legiQature over thefe colonies, but as the fupreme legiflature and full reprefentalive of the parent ftate, and the only judge between her and her children in commercial interefts, which the nature of the cafe, in the progrefs of their growth admitted. It has been urged, with great vehemence againll us, and feems to be thought their fort by our adverfaries, " thatapowerofregulation is a power of legillation, and a jpower of legillation, if ' ,. . ^ conflitutional, ** The jurfdidion of the ftar chamber, martial law, imprifonment by warrants from the privy council, and other practices of a like nature, ihough ejiablijhed for fe'veral €entMries ; were fcarce ever allowed by the Englijh to be parts of their conftitution : the affection of thb The exercife of i^tiz powers, after being long the fource of fecret murmurs among the people, was, in fulnefs of time, folemnly aboUfhed, as illegal, at leall as oppreffive, by the whole legillative authority." id. To thefe inilances may be added, the late pradlice of general warrants, that had the iaaftion of precedents, even fines the revolution. conftitutional, miift be univerlal ' and Aipi^^lnl^* in the utmoll Icnfe of the words. It is thcl-e^"^'^ tore concluded, that the colonifts, by acknow-' ledging the power of regulation, have acknow^' ledged every other power." On this objedion'"we obferve, that according to a maxim of lav/, " ' it is deceitful and dangerous to deal in general propofitions." The freedom and happincfs of flates depend not on § arlful argument s^ but " ■/'" ' . ' ■ on '"-'[ § Our chance of fuccefs would be flight indeed, if it depended on ("ubieties of reafoning. Who can refift the ikilful and courageous attacks of thofc Britons, who have not long fince diftinguifhed themfeives in the polemical fields ? Have they not />7?i;^i/ to the fatisfadion of thoufands, the non exiftence of matter — the neceifity of human aftions—confequcntly the in.iocence of ihem — the comfortable mor-. . tality ofthe foul — that virtue is a name — vice a jell — liberty a nonentity — chiilHanity an impofture — and, \vith due detv=:ftation be it mentioned ; that we have no ^dea oi po^wer^ nor of any Being endowed with any power, much less of one endowed with infinite power : " With explofions of learning and flalhes of wit, thefe welt trained troops would keep up a terrible fire of artillery and fmall arnis againll us undifcipUhed Americans. We mult not meet them in the fnock of battle. That would BE MADNESS IN THE EXTREME. We mult make the mofl of our natural aivan-ac;es. — — ^['here we are fafe ; and all ^ the forces that can be brouglit to the afTault, will never be able to prevail againll us. To drop the metaphor. ** Inquiry ccafes to be rational, and becomes b-^th whimficfll and pernicious, when it advances as far as feme late authors have carried it, to coutrovert the flrll prihciplcs of knowledge, morality, religion, and confequently the fiin-* damentai laws of the Britijh government, and of all well on a few plain principles. The plaufible appQ^rance of the objedion confiUs in a ronfufed comprehenfion of feveral points, entirely diftinft irf ♦j^; their nature, and leading to confequences diredt- 4, \y oppofite to each other. The^e was a timcj h, i when England had no colonies. Trade was theU4. objedt Ihe attended to, in encouraging them,-''^ A love of freedom was manifeilly the chief mo- ' ^' tive of the adventurers. The connexion of co- ' '" lonies witii their parent ftate, may be called a ' new objedt of the Englijb laws. That her right ' extinguilhes all their rights, — rights effential to freedom, and which they would have enjoyed, by remaining in their parent ftate, is offenfivc to s reafon, humanity, and the conllitution of that ftate. Colonies could not have been planted on ' i^efe terms. What Englijbman, but an ideot,' would have become a colonifl on thele conditions ? to mention no more particulars, '' That every fhilling he gained, might rightfully be taken from him — trial by jury abolifhed — ti* . building houfes or making cloths with the mate- ^^ rials found or raifed in the colonies prohibited— '■;;' '^;' and armed men fet over him to govern him in, every a6lion ?", . P .^.^, _ Had ' It has been aflerted by fome men diftinguiftied as hifto-.>; -0^ rians, that the zeal of the reformers in religion engaging:^; a^, them to think liberally on that fubjedl, led them tJ thinK . ."^^vaft. with like freedom in civil affairs, whereby the government _^ of England TQCtvrtd its greateft improvement. If the icn- "^ timent is jufl, may it not be inferred, that contempt for re- ^5^ -ligioii, mull neceflarily introduce an indifference for all dii»^ ■'**** j 'ill riUes of government & the principles of the conilitation ^pt^isnti Had thefe provinces never been fettled — had til the inhabitants of them now living, been born in England^ and refident there, they would now enjoy the rights of Englijhmeny that is, they would be free in that kingdom. We claim in the cflonies thefe and no other rights. There no other kingdom or ft ate interferes. But their trade, however important it may be, as the affairs of mankind are circumftanced, turns on other principles. All the power of parliament cannot regulate that at their pleafure. It muft be regulated not by parliament alone, but by treaties and alliances formed by the king without the conisENT OF THE NATION, with Other ftatcs and kingdoms. The freedom of a people conjijis in leing governed by laws^ in which no alteration can be made^ without their confent. Yet the wholefome force of thefe laws is confined to the limits of their own country. That is, a fu- ' preme legillature to a people, which ads inter* nally over that people, and inevitably implies ferfonal zStnty reprefentation^ oxjlavery. When an univerfal empire is eftablilhed, and not till then, can regulations of trade properly be called, a6ls of fupreme legiflature. It feems from was little regarded by our warlike anceftors. Ar, commerce became of more importance, duties, and feverities were judged neceflary additions to its firft fimple (late, parliament more and more interfered. The conftitution was always free, but not always exadlly in the fame manner. " By the Feodal law, all navigable rivers and havens were computed among the Regalia, and were fubjed to the fovereign of the ftate. Arid in England it hath always been held, that the king is lord of the whole Ihore, and particularly is guardian of the ports and havens, which are the inlets and gates of the realm : and therefore, fo early as the reign of king John, we find (hips feized by the kings officers, for pitting in at a place that was not a legal port. Thefe legal ports were undoubtedly at firft affigned by the crown , fmce to each of them a court of portmote is_ incident, the jurifdidion of which muft flow from the royal authority. The erection of beacons, lighthoufes, and fea marks is alfo a branch of the royal prerogative. The king may injoin any man from going abroad, or command any man to return. The powers of ; eftabhlhing public marts, regulating of weights and meafures, and the giving authority to, or making current, money, the medium of com . merce^ belong to the crown. By making peace "or war, leagues, and treaties, the king may J Open or flop trade as he plcafcs. The admiralty ixourts are grounded on the necefTity of fupporting a jurifdidioa fo extenfive, though oppofite to the ufual dodlrincs of the common Uw. The . laws oi Oleron were. made by Richard the firll, V and are dill ufcd in thofe courts." In the " Marc ■ caufum", arc fcveral regulations made by ;'♦ The power of regulating trade, was carried fo far by .the crown, as fometinies toimpofc duties; and queen Elixahtth obtained feveral judgments in the exchequer on fuch regulations. Lord chief jurtice Coke anfwers the argument founded on thcfe— -in z inlt. 62. 6^. Princes aimed at too produced " grievances" — and ihe people who always fufieif when their rulers are weak or wicked, would no longer trjill fuch opportunities of opprejjion in their hand. The •.power of itnj)rejj\ng feamen, Ihews the cxtenfivc authority j^ naval aj^airs truiUd to * the crown." •1"' ' " ^ . ,. .'f :.\| Blackft. 419. Foftcrsrep. 154. • .-So extremely averf<p were the Englijh to foreign affairs , fnd to the exerdfe even of parliamentary authority concerning them, that though the nation was juflly provoked againil the French king for the injury done to Ednuard the I ft by withholding Aquitatne and his other inheritances in inanner (as lord chief juilice Coke obferves in his 2d infl. pa. 532) and by fpme cruel aftioirs of Frenchmen againft ^nglijhmen,) and had in full parliament granted him aids, fubfidies, for the maintenance of his Wars in foreign parts, yet in the confirmationes chartarum, Ed, I ft, therein taking notice. " that many men doubted, whether thefe grants by parliament might not turn injervagt ^ them and their heirs, as precedents, exprefsly declares ii^ thofj^ ftatutes, that fuch grants (hall not be drawn into cuf* torn'.'' The comment fays— " it was holden that the fub- je£ls ofii/pe realm ought not to contribute to the maintenance of the kings wars out of the realm —but this .F.atter wds never in quiet, until it was more particularly explained by divers ad^s of parliament." The comment then mentions fevcral ads declaring that no EngliJIjman (hall be bound to contribute to the kings wars out of England^ in Bcotlandy Gajcoigny, Ireland, Calais^) though theje three la/i were countries dependant on England,) and fays, " thefe ads of parliament are but declaiatiunb of the antient law of England- But here may be obferved, that when any antient law or cuOom of parliament" (fuch as before mentioned by making ads relating to foreign wars) " is broken, and the crown poireffcd of a precedent, how difficult a thing it is, V The author of " the controv^rfy," tvho with a liberality of fentiment becoming a pleader againll freedom and the bell intereft of mankind, counts, " ilatute books" — ' minifters" — •* king's council" — ^pa. 77. 78. — fcraps of journals" pa. 8{. and ordinances of " the rump parliament"——pa. 87. among his DEITIES" pa. y^ ; and grieves that we poor ♦' inJiJel" colonills will not pay his idols the veneration his z<al judges due to them, has co!leded a good many fragments of proceedings in the houfL* of commons from the year i6i4to i6z8. The amount is this, that the minilters of the erown infifled, that parliament could not make laws for Amerua\ that the the commons doubted ; but at length in 1724, came to an, opinion, that the king's patent for " a monopoly of filhing ^forfeiture" againft thofe who inteifered in the fifhery was void — and pall a bill " for a /^w liberty oi fJJjing^* 8ec» It appears in the debates that the filhery was free hefore the patent 'uj as granted — Thefc exlrads do not flicw, what . became ih6 ttowhy Aat our argument may gain, but cannot lofe. We will proceed on a conccflion, that the power of regulating trade is yelled in parliament. ^ Commerce refls on conceflions and reftridlions mutually ftipulated between the different powers of the world j f and if thefe colonies were fovereign ftates, they would in all probability be reftrided to their prefent portion . The peo- liecame of the bill in the houfe of lords. One Mr. Srcoh hid in 1621 ——« We may make laws here for Firginia, for i/tb king gives tonjeni to this bill pail here and by the iords* this will controul the patent." It feems, as if the notion of the king's regulating power iUll prevailed, but, that" a claufe of /or^i//vr«" in fuch regttiations was void." So much had the power of parliament grown iince king JobHs reign. Nor does it appear to have been unreafonable, as commerce became of l&ore confequence. The inftance here mentioned, related ite m regulation of trade; and however the king might have ' iceommodated the point, with the other branches of the Ic 'giflature, the whole proceeding is immaterial. If it was [^ right actually enjoyed by EngUJhmeH to fiAi on the coafts ; of a plantation—; ad a grant by the crown of the filhery to ^ fhe people of the plantation excluding the people of MngianJ, r could not WSro;^ them of their right — or, •• if by the king'i . ';giving his confent to a bill paffed by lords and commons, -— «« thfe patent might be controuled" — it does not follow, ' that the king, lords and commons could diveft the people ;^©f the plantations of all tbeir rights, ^^i u r.tttv ,^, «!«r^ • t Cafe of the OjiinJ Eaft InMm company, iv -li^ uiWr " Another light, in which the laws of BngUnd confi* der the king with regard to domelHc concerns, is the arbi* cer of commerce. By commerce, I at prefent mean domeftic in the folid foundation of her conflitution, and an empty name in her colonies ? I'he lamb that prefumed to drink in the fame fir earn with a ftronger animal* though lower down the currenty commerce only. It would lead me into too large a field, if I were to attempt to enter upon the nature of foreign tradcy its privileges, regulations, and reftridions ; and would be alfo quite beftde the purpofe of thefe commentaries, which are confined to the laws of England. Whereas no municipal Iwws can be fufficient to order and determine the very extenji've and complicated affairs of traffic and merchandize j neither can they have a proper authority for this purpofe. For, as thefe are tranladions carried on between fubjefls of independent dates, the municiple laws of one will not be regarded by the other. For which reaibn the affairs of commerce are regulated by a law of their own, called the law merchant or lex mereatoria, « which all nations agree in and take notice of. And in particular (it is held to be part of the law of England, which decides the caufes of merchants by the general rules which obtain in all commercial countries ; and that often even in matters relating to domeftic trade, as for inftance with regard to the drawing, the acceptance, and the tranffer of inland bills of exchange/' L120 I coukl not refute the charge of incommoding ktter, by difturbiag the water. Suqh power have realbni that appear dcfpicable and deteflable a^ lirit v/hcn they are properly enforced. /.i/.v.\ FnoM this very principle arofe her power -, and can //W power now bcjujHy exerted, infupprejjion of that principle ? It cannot. Therefore, a power * of regulating our trade, involves not * This diilincHon between a fuprenie legiflature and a power of regulating trade, is not a new one. We find it clearly made, by the judges of £;/^/^/7//, at a period, when the modern prohtabie mode of blending rogether in j arliament the auilioiities of the crown and people, had not cxtinguilhcd all reverence for the principles of the con- Ky the ftntutc of the zAo^ Henry G\\i ch. 4th Calais v:n$ confirmed a rtaple place for the wool exported from Englanci, PFales and Ireland, Some wool (hipped from this lad kingdom, was config ed to ^/w/cf, in Flanders. The ihip by llrefs of weather was forced into Calais^ where the wool was feizcd as forftited. The chief queftion in the exchequer chamber was, whether the ftatute bound Ireland. In Richi: 3, 12, the cafe is thus reported. • Et ibi quoad ad primam qjeftionem dicebant,quod terra M'^fm^r inter fe habet farJiamcnturn Sc omnimodo cur:as prout in Anglia^ & per idem parliam<ntum faciunt leges & mutant leges, & non obli- PERsoNi^ EORUM SUNT suBjEcri REGIS ct tanquam fubjeili ESlUNT obligati ad aliquam rem bxtra terraw ii.LAM KACiENUAM cootra (latutum, ficut habitilntes in Calhfiiiy G.iJ'cogrfia, Guien, &c. dum fuere fubjefti ; &obedientes cruiit SUB admkalitate ANCLiiE db rb facta .SUPER ALTU M MIRE; ti fimiUter breve de errore de judiciis ledditis in Hibernia in banco regis hie in JnzUa.* 90 fays—" the chief juOice was of opinion, that the ftatutcs of England fliall bind Irelunti, which was in a manner agreed by the other juflices ; and yet it was denied the former day: Yet note, that Ire/anJ is a realm of ilfelf, and i'at a parliament in ilfelf " Here it may be obferved, firfl, that the reafon affigned. by the judges, why the llatutes of England bind not the pe9p!e oi Ireland, though fpeciallj named, contains a conftituti.)nal principle, the fine qua of freedom Secondly, that the pjoiple of he'and, as fubj^-dls of the king, were ' under toe admiralty of England as to things done on the high fea'j" w'lich u a ilrong conhrmatiun given by the judges of England, to the fupppfition before madf, of the power of regulating trade being forme/ ly veftcd in the king, Ihirdly, that the opinion of the chiel jullice, and of the other jultices, fuch as it was, * reddendo fjngula fingalis, ic fecundum fubje^tam materiam," piove& at mod, only that /r/fl»<^ was bound by Jiatutes regulating their trade, for fuch was the 2 Henry 6th ch. 4th on which the cafe arofe. Fi^nrthly^ \\\zx Bro(jke z, man of great eminence and dignity in the law, appears by his note, to have been difTatisfied with the judgment, tho onl) on a ftature of regulation, for this reaion of fuch weight with »n Englijbman, — ' becaufe Ireland is a realm ot itlelf and has a parliament within itfelf " Fifthly, that the authority of the crown, including the regulation of the trade oi It eland, and fending writs of error there, were fulficient rellraints, to fec.irc the obedience and fubordination of that kingdom. This reafon fcems to have held its ground, till loru chief jullic* Ccke^i time; and though a great reverence is entertained for his memory, yet it can never be ackn \^'!edj»ed, rhai an '* obiter dietun^ of his, or of any .Other man, is a rule of law. \ In! Calviti'% cafe, the chief jufticc reciiii.g luc tortguing Cufc, lays, '* Hihernia habet pariiamentuin, Sc laciunt lei',es, Sc nof^ra Itatuta non legant ecs, quia non mittunt inilite^ ad parliamentum (which ••' adds he," is to be underJicod, unlefs they be ejpecially named) Atid does the " cfpecially naming them," give them a rcprelentation, or jemove the injulHce of binding them without it? This ob- , ft:' vation in plain Englilh would run thui. " Our itatutes . been thought in England, that llatutc^ Aould generally bind the people of thole countries, notwlti ilanding ihe fubjection of Inland, and the other ifland;). the many diftrefles of the former, and the weaktieU of the latter have afforded f)pporiunitie« of extending fuch a power over them. With rcfppc\ to all ihefe places fcarce a ttatute can be found of any period, but for f e regulation of their trade. The fame obfervation may be made as to Ga/coigny, Guienne znd Calah, Juflice ffylde in 2 vent. 5, faid, he had feen a charter whereby thefe placts were recited to be united to England by mutual pa^. Aiid writs of error run thofe." Walts was a conquered country, and the people fubmitted to Eaiuard the fifft de alto et hjo, , „ Whatever pretence thcchitf j nlice's opinion was founded on, u has bv-ent.ic.u i i. , c.icd in many law bt)(<k,s iince. Whtihtr hi>> l>nilh fMncaiit, tha- fta.ntcs of TT/i^/aWcoulil ^1./ the people ot ///.wirf, in tnkirig away trials by jury,--taxing thfiu, and in ailcti ts ivhui/ofvtr^^* or on y in prefci .i.ig 'hew iuboidination, as by rtguiatlng their tradc^ which was the caic icTened to in his coin>iient, docs not appear. Tne parliament in declaring the dependence of Inland, did not <ve nt ur e \oc\dSm a power of binding the prOj^ii ot tiiat kinguom '* in all ca(i.s whatfoever "* With rtlpect to all ihcle declarations, however, as they are made to ittc-r to u), we ma/ aufwer an the lion did to the man in the table, Much the fame arbitrary coi.ft.uflion has been made on the qucUi'jn ; whe lier a man could tic tried in Evgtand on a charge of comnuttiug in'iifon in Ireland, n aiieen ElizaItth'i 'cign, ** Gtrrade^ chancellor oi' Leiand im>vL-d that queltion to the couiUe ot the queer, and it was held by }yray^ Ditr, and (ierrarde, attorne^' gerej' ', he could not, becaui'e he wa.-> a fubjcct of Ireland And not of England^ and if tiitd in England, he could not be tried by his peers." Dietj 360. Auerwards, to gratify the queen's refeutmcnt againit fome rehel>, they weie tried in England ; and thus pailion and c ^mplaifancc made ^ery good law agaioll reafon and juilice. Having mentioned Cal'via^s cafe, it may not be improper to oblerve, that it the author of ♦* the controverfy" had taken the trouble of reading it, he might have found hia perplexities removed on the quelHon that has given him fo much aikxieiy, and brought fuch aIo«d of reproaches on the colonies. He is provoked at cur infolcncc for pretending to be any thing moie than aliens in England, while we deny the power of parliament to bind us ' in all cafes whatever.' In that cafe, the gentieman would have difcuvered, that the judges of England held, tha. a man born in Scotland, under tht allegianct of James the firlt, after his acceflion to the movements." The firft is a power fubjedl to a conllitutional check. Great Britain cannot m-r jure us by taking away our commerce without \,,j.ji^^hLjrting herkif immediately. The lafl is a pow^.Hi;i-j,er without check or limit. She might ruin us nil J j>y it. The injury thereby to herfclf might be hau . r^»/(?/^ as to be defpifed by her. ■■-^^^■vy^ hi: \n lii The power of regMlati;)n was the only band ♦■hat ;j t >// could have held us tosrether -, formed on one of thefe " original contrails/* — -which only can be -''' '-"a foundation of juft authority. Without fuch a band, our general commerce \yith foreign natiqns, might have been injurious and deftrudive to her. Reafon and duty rejedl fuch a licence. This our duty refembles that of children to a parent. The parent has a power over them : but 7 have rights, what tl;? parent cannot take ' "jiway. llcuven grant that our mothc; countrymay regard us as her children, that if by the dilpcnfation of Providence, the time fhall come, nwhcn her power incrcafes the memory of foriner kindneifes, may fupply its decays, and her colonies like dutiful children, may fcrve and guard their aged parent, for ever revering the arms that held tiiem in their infancy, and the breads that fupported their lives, vvliile they were littleones. .. ..., v i. .r •* . «■ ^^'/H? ^ , It feerns, as if the power of regulation might not inaptly be compared to the prerogative of making peace, war, treaties, or alliances, whereby ' the whole VMtion are bounds against their, consen^t:" and yet the prerogative by no means implies a fupreme legijlature. The lan-r guage held in " the Commeniaries " on this point is very icniarkable. " ""Vith regard to FORLiGN CONCERNS the king is the delegate or reprcfentaiive of the people •, and in him, as in a center^ all the rays of his people are united \|\| ; and the sovereign pow.iR qticad hoc is veiled in his perfon §j." Will any Englipnian fay thefc expreiTions are def :riptive of the king's authority, POWER within /;?7^/ veiled in his perfon :" He is fliled " fo'vercigff indeed -, " his realm is, declared by many ads of parliament an Empire and his crown Imperial:' But do thefe fplendid appellations, the higheft known in Eitrope figni\ly, that '^fovereign power in veiled in his perion within the realm ? " We have a full anfwer ii; the Commentaries. " The meaning of the legifl::tiire, when it ufes thefe terms of empire and imperial^ and applies them to the reahn and crown of England^ is c«/y to afTert, that our king is c(\\\2i\\y fo'vcreign and independent within thtle his dominions \ and ewes no kind of Juhjetiion to any potentate upon c^rch." I'hus wi- maintain, that with regard to foreign affairs, the parent original ilate, " is the delegate or reprejentative^^ of the entire dominions, " the f over eiga power QUOAD HOC is veiled " in her. Her acts under this power " irrevocably bind the whole nation." B'lt yet this power by no means im olies afupreme kgijlatnre. This power of regulation appears to us to have been pure in its principle, fimple in its operation, and falutary in its efTeds. But for fomc time pall we have obferved, with pain, that it hath been turned to other purpofes, th^n it was originally defigned for, and retaining its title, hath become an engine of intolerable op^ prcfiions and grievous taxations. The argument of an eminent judge. Hates the point in a fimilar cale itrongly tor us, in thcic words. — " Though it be granted, that the king hath the cujlody ot the havens and ports of this ifland, being the very gates of this kingdom, and is trujled with the keys of thefe gates \ yet the inference and argument thereupon made, I utterly deny. For in it there is mutatio hypcthefis^ and a tratiption from a thing dione nature to another \ as the premijes are of 2i power only fiduciary^ and in point of tritji and government^ and the concluficn infers a right of intereji and gain. Admit the king has cuftodiam portuum, yet he hath but the cuficdyy which is a truji and not dominium tilile. tie hath power to open zxi^jhtit^ upon consideration OF PUBLIC GOOD TO THE PEOPLE AND STATE, bvU not to make gain and benefit by it : the one is r isOTECTioN, the^//??^r is expilation." BycomT ov; law the king may reitrain a fubjcct from going abroad, or enjoin him by his chancellor from proceeding at law : But to conclude^ that he may therefore take money^ not to reilrain or not to enjoin, is to sell government, trust, Df'f ill pa 39 tlufc words — '• no EnghPo'y f" thcconftifutirtn lawvtr, pi> x'i* J« member, has pointed out > r. < ha* not exprrfsly pre 'fcly" ■ - — — and j ^ drawn." !>< It in n<>tc oFpa. 47 — this word— ^" hfcauft." Ill note oF pa. 51 — after 7 Geo. 3 ih. 41. — r. 7 Geo. j ch. 4. In note of pa. fit. after the word " Govcrnmem;" — r., •' confifts" In note of pa. 84 for "pa. lai" — r.— p. no. rr^J^F- ftatuteifincc the 8th year of this reign relalinj? to the colo^ ;a;* nics, fallow one ahothtr much in thf fame qiiick m.inucr ai btfore: but they could not be cv)llcd;( d. Many of the ftatutes lure nicntionff! particularly tho^- 'elating to the admiralty courts a'ld the comm iriiiners of the curt , «:- connedli-d with a multitude of other ft:Uutes, bv btin(» €• A with which; the artificcN will appear, thiC gradn il y dtpa» g fiom the l.iws of Eng' land, have at Icngili invcft"d thffif cnuit* and commiffimers with fuch new, unrctfonabte, unconftitutinnal and dangerous powers. Addicional Note to pa. 80. pire then comprehandt'd in Europe, all >pn'ui and Portugal, the two Siciiits, and Inch provinces of the Loiv Countries a» adhered to Iiim, . — nray iflards (tf imp >!tar.cc in ;he Mediterranean — the Milantfe and many other v^ry valuable teiritoties in //a/v and elfewhcre.— • In Afi'ica iiul Afta^ all the dominions belonging to ^'^jjiu, and Portagol — in /imeiica xhc\mTii<T\{c countries fuhjc»f^ to thofe two kingd:)iMj, wiib all their treaAir^t and yet aneihanrtcd mines, and thd Spauijh tVe!J-!t,dies. His armies were.niimerous and veteran, eicelIfotly officered, and command'.d by the'n'ioft renowned general. So great was their force, that during the wars in the Lnv Countriei, liis roniniander in chief the prince of Parma, marched twice into France, and > bhgtd that great general and glorious king Henry the fourch. to raife ar one time the (iege of Paris and at another, that' of Roan. So confiderable was the naval power of Philip, that in the rriclrtofthe fimewats, he fi fed out his dreadful armada to invade F-ngland." Yet fcvcn little provinces, or counties, as we iLould call thcni, infpired by one generous refolution — " to die free, rather , than to live Haves," not only bafllcd, but broii'ght down into .^h«i, doft, that enormous- power, that had contended for univerfa! em-' phe, and for half a ctniurv, was the terror of the world. Such afi , amazing change indctd took pUce, that tHofc provinces afterwaidfr a^ualiy protectsd Spein agalnft the power of Frjuct. ■ '	47,406	common-pile/pre_1929_books_filtered	cihm_20475	public_library	public_library_1929_dolma-0024.json.gz:4490	https://archive.org/download/cihm_20475/cihm_20475_djvu.txt
EWiXIS7i8RfCnq7B	2.1.2.2.4: Sample Biography - Max Weber (1854-1920)	<IP_ADDRESS>.4: Sample Biography - Max Weber (1854-1920) - - Last updated - Save as PDF MAX WEBER (1864-1920) “Die bange Nacht is nun herum wir reiten still, wir reiten stumm wir reiten ins Verderben” – Herwegh, Reiterlied [1] NOTE ON SOURCES: We are fortunate to have a comprehensive biography of Max Weber written by his wife, Marianne, first published six years after his death, in 1926. For decades, this was the primary source of information about Weber’s life. Recently, however, our knowledge in this area has been greatly supplemented by Joachim Radkau’s Max Weber: A Biography, published in English in 2009. Radkau’s sympathetic portrait nevertheless includes several less flattering details of Weber’s personality and character, not included in his wife’s biography. For more on Weber’s intellectual development, and less about his personal life, read Fritz Ringer’s Max Weber: An Intellectual Biography, published in 2004. Overview Max, full name Maximilian Karl Emil, Weber was born in Erfurt, a bustling commercial city in what is now central Germany, on April 21, 1864. Weber spent his life in a rapidly industrializing and increasing militaristic Germany, living through the devastations of the first World War, and witnessing the rise of fascism during the early years of the Weimar Republic. Like many writers and thinkers of his day, he was interested in how this new industrial society came to be. His most famous work, The Protestant Ethic and the Spirit of Capitalism , was a partial answer to that question. Weber would also come to create a particular approach to sociological inquiry, more focused on interpretation and less focused on policy proposals than Durkheim’s. Social Background/Family Weber was the first of eight children, born to a wealthy statesman (Max Weber, Sr.) and his somewhat devout wife Helene (Fallenstein). The Webers had been a prosperous family for many generations, making their money in the linen trade. Max grew up in bourgeois comfort, in a home devoted to politics and intellectual pursuits. In fact, Weber’s younger brother, Alfred, would also become a sociologist. Education and Training In 1882, Max earned his high school diploma and, according to his wife’s biography, “also helped his friends to cheat their way through.” His teachers, she claimed expressed some doubts about his moral maturity, finding him a troublesome if intelligent student. At age 18, he enrolled at the University of Heidelberg, where he followed in his father’s footsteps by studying law. He also took up fencing at his father’s fraternity house. Marianne tells us he had no talent for saving money and would often ask for increases to his allowance. In his second year, he took time off to serve in the military, but found military life difficult. He liked the military much more after entering into officer’s training, and he left the following year with admiration of the “machine” and a greater sense of patriotism. He returned to university and eventually earned a law degree in 1889, with a dissertation on the history of trading companies in the Middle Ages. For seven years he lived in the family home, studying further and teaching classes when he could. He did not leave home until his marriage in 1893, to his cousin Marianne Schnitger. During this time, Marianne tells us, he felt oppressed by his father, who ran his house with strong authority, requiring obedience of his children and his wife, who suffered a great deal. Max, she says, “was reserved and never asked relieved himself by a frank discussion of the problems. He repressed everything.” He urgently wanted to leave. When his cousin came to visit, moving from the country to the city, they quickly became attached. Here is how Marianne tells the story of their engagement: The seriousness of their relationship was lightened by their sparkling humor and impish banter. The engagement was still supposed to be kept secret, but as Weber remarked, “Every jackass here gives me a meaningful look and asks me whether something has happened to me. I would never have thought I was beaming so.” Career In 1894, the newly married couple moved to Freiburg, where Weber was appointed Professor of Economics. In 1896, they moved to the Heidelberg, where Weber continued as an Economics Professor. He spent his time researching and writing on economics and legal history. Max and Marianne had no children. Instead, they maintained a vibrant social circle of intellectuals. In 1897, Max’s father died. Max and his father had quarreled two months before, particularly about his father’s treatment of his mother, and every biographer points out that the death hit Max very hard. He became depressed and suffered insomnia. Eventually, he had to leave teaching altogether to spend some time in recovery. He made one brief foray back into teaching in 1902 but left again in 1903 and would not return to an official posting until 1919, one year before his death. During that time, he wrote much that would be published after his death, on matters sociological and political. He spent much of 1904 touring the United States, notes and letters of which letters have recently been published. [2] Given the importance of Benjamin Franklin to his own understanding of the development of the spirit of capitalism, visiting the United States was an important chapter in his life. Weber took many notes on what he witnessed there. When visiting upstate New York, he observed, My trip to Buffalo yesterday was very pleasant, even though all the walking around along lengthy streets was fairly strenuous. Despite the magnificent buildings, the shopping streets as a whole look no more inviting than those in New York: Everything is obscured with a black sooty haze, windows are sometimes dirty- in short, new and yet already falling into disrepair, somewhat like our own suburbs., By contrast, the residential district is the world of elegance, nothing but tree-lined green streets with charming wood-frame houses that look as if someone had just taken them out of the toy box and placed them on the velvety green lawn. They are the only completely new and original architecture that I’ve seen here so far, and aesthetically far more satisfying than the imposing stone palaces in New York (September 9th). In contrast to this pleasant scene, Weber was struck by the dirty sootiness of Chicago, the fifth largest city in the world at the time, Chicago is one of the most unbelievable cities. In the city among the skyscrapers, the condition of the streets is utterly hair-raising. Soft coal is burned there. When the hot dry wind off the wastelands to the southwest blows through the streets, and especially when the dark yellow sunsets, the city looks fantastic…. Everything is mist and think haze, and the whole lake is covered by a purple pall of smoke…It is an endless human desert….[In the stockyards], for as far as one can see from the Armour firm’s clock tower there is nothing but herds of cattle, lowing, bleating, endless filth. But on the horizon, all around – for the city continues for miles and miles until it melts into the multitude of the suburbs – there are churches and chapels, grain elevators, smoking chimneys, and houses of every size (September 19th). In 1907, he received an inheritance that allowed him to put off paid employment. He and Marianne lived well and continued to host intellectual parties and discussions. They experimented (disastrously says Radkau) with an open marriage. In 1909 Weber helped found the German Sociological Association, serving as its first treasurer. In 1912, he tried to organize a leftist political party, but was ultimately unsuccessful. When World War I began, in 1914, Weber volunteered and was appointed as a reserve officer. Weber would eventually become a strong critic of Germany’s nationalist expansionism and called for the expansion of suffrage. He was one of the advisers to the committee that drafted the Weimar Constitution. He unsuccessfully ran for a seat in parliament. It was at this time that he returned to the university, where he gave a famous lecture criticizing opportunistic politicians. The lectures from his last year of life were written down and have circulated as important Weberian texts for years. At the time of his death, he was working on what he considered his masterwork, Economy and Society . Marianne would continue the work and publish it as Max’s own in 1922. Marianne continued to work his notes and half-finished manuscripts into books and publish them for the next several years. His Work In the early years, Weber wrote mostly on legal history and economics. He was very productive during this time and published his dissertation on trading companies in the middle ages in 1889, a book on Roman agrarian history in 1891, a book on farm labor in Eastern Germany in 1892, a book on the stock exchange in 1894, and a book on the state and economic policy in 1895. After his father’s death, it was several years before he could work again. He wrote The Protestant Ethic and the Spirit of Capitalism , first published as an essay in 1904. This work marks his turn to more sociological writing. Although he continued to write and lecture in these later years, almost everything was left unfinished at his death. Marianne Weber did much to compile and publish this later work, including his famous Economy and Society (1922) and General Economic History (1924). The English-speaking world knows Weber primarily through translation, and most of these translations were completed in the 1940s and 1950s, many by Talcott Parsons, the great mid-century American sociologist working out of Harvard University. Questions - How does Weber’s background and career compare to that of Durkheim, his near contemporary? To Marx? - Weber was a keen observer. How is this evidence in the brief extracts from his 1904 visit to the United States? - This is a song Weber was known to sing near the end of his life, during the tumultuous Weimar years. It can be translated as, “The anxious night is over now; we are riding quietly, we are riding silently, we are riding to perdition.” (Marianne Weber, Max Weber, Wiley and Sons (1975 translation)). ↵ - See Scaff’s Max Weber in America (2011). ↵	2,208	common-pile/libretexts_filtered	https://socialsci.libretexts.org/Courses/Pueblo_Community_College/AH1%3A_Communication_and_Popular_Culture/02%3A_Textual_Analysis/2.01%3A_Rhetorical_Criticism/2.1.02%3A_Rhetorical_Lenses/2.1.2.02%3A_Biographical_Study/2.1.2.2.04%3A_Sample_Biography_-_Max_Weber_(1854-1920)	libretexts	libretexts-0000.json.gz:27148	https://socialsci.libretexts.org/Courses/Pueblo_Community_College/AH1%3A_Communication_and_Popular_Culture/02%3A_Textual_Analysis/2.01%3A_Rhetorical_Criticism/2.1.02%3A_Rhetorical_Lenses/2.1.2.02%3A_Biographical_Study/2.1.2.2.04%3A_Sample_Biography_-_Max_Weber_(1854-1920)
0xG9hBum-wWDtdlC	19.6: Capacitors in Series and Parallel	19.6: Capacitors in Series and Parallel Learning Objectives By the end of this section, you will be able to: - Derive expressions for total capacitance in series and in parallel. - Identify series and parallel parts in the combination of connection of capacitors. - Calculate the effective capacitance in series and parallel given individual capacitances. Several capacitors may be connected together in a variety of applications. Multiple connections of capacitors act like a single equivalent capacitor. The total capacitance of this equivalent single capacitor depends both on the individual capacitors and how they are connected. There are two simple and common types of connections, called series and parallel , for which we can easily calculate the total capacitance. Certain more complicated connections can also be related to combinations of series and parallel. Capacitance in Series Figure $\PageIndex{1}$(a) shows a series connection of three capacitors with a voltage applied. As for any capacitor, the capacitance of the combination is related to charge and voltage by $C=\dfrac{Q}{V}$. Note in Figure $\PageIndex{1}$ that opposite charges of magnitude $Q$ flow to either side of the originally uncharged combination of capacitors when the voltage $V$ is applied. Conservation of charge requires that equal-magnitude charges be created on the plates of the individual capacitors, since charge is only being separated in these originally neutral devices. The end result is that the combination resembles a single capacitor with an effective plate separation greater than that of the individual capacitors alone. (See Figure $\PageIndex{1}$(b).) Larger plate separation means smaller capacitance. It is a general feature of series connections of capacitors that the total capacitance is less than any of the individual capacitances. We can find an expression for the total capacitance by considering the voltage across the individual capacitors shown in Figure $\PageIndex{1}$. Solving $C=\dfrac{Q}{V}$ for $V$ gives $V=\dfrac{Q}{C}$. The voltages across the individual capacitors are thus $V_{1} =\dfrac{Q}{C_{1}}$, $V_{2}=\dfrac{Q}{C_{2}}$, and $V_{3}=\dfrac{Q}{C_{3}}$. The total voltage is the sum of the individual voltages: \[V=V_{1}+V_{2}+V_{3}.\] Now, calling the total capacitance $C_{\mathrm{S}}$ for series capacitance, consider that \[V=\dfrac{Q}{C_{\mathrm{S}}}=V_{1}+V_{2}+V_{3}.\] Entering the expressions for $V_{1}$, $V_{2}$, and $V_{3}$, we get \[\dfrac{Q}{C_{\mathrm{S}}}=\dfrac{Q}{C_{1}}+\dfrac{Q}{C_{2}}+\dfrac{Q}{C_{3}}.\] Canceling the $Q$s, we obtain the equation for the total capacitance in series $C_{\mathrm{S}}$ to be \[\dfrac{1}{C_{\mathrm{S}}}=\dfrac{1}{C_{1}}+\dfrac{1}{C_{2}}+\dfrac{1}{C_{3}}+\ldots ,\] where “...” indicates that the expression is valid for any number of capacitors connected in series. An expression of this form always results in a total capacitance $C_{\mathrm{S}}$ that is less than any of the individual capacitances $C_{1}$, $C_{2}$, $\ldots$, as the next example illustrates. TOTAL CAPACITANCE IN SERIES, $C_{\mathrm{S}}$ Total capacitance in series: $\dfrac{1}{C_{\mathrm{S}}}=\dfrac{1}{C_{1}}+\dfrac{1}{C_{2}}+\dfrac{1}{C_{3}}+\ldots$ Example $\PageIndex{1}$: What Is the Series Capacitance? Find the total capacitance for three capacitors connected in series, given their individual capacitances are 1.000, 5.000, and 8.000$\mu \mathrm{F}$. Strategy With the given information, the total capacitance can be found using the equation for capacitance in series. Solution Entering the given capacitances into the expression for $\dfrac{1}{C_{\mathrm{S}}}$ gives $\dfrac{1}{C_{\mathrm{S}}}=\dfrac{1}{C_{1}}+\dfrac{1}{C_{2}}+\dfrac{1}{C_{3}}.$ \[\dfrac{1}{C_{\mathrm{S}}}=\dfrac{1}{1.000\mu \mathrm{F}}+\dfrac{1}{5.000\mu \mathrm{F}}+\dfrac{1}{8.000\mu \mathrm{F}}=\dfrac{1.325}{\mu \mathrm{F}}\] Inverting to find $C_{\mathrm{S}}$ yields $C_{\mathrm{S}}=\dfrac{\mu \mathrm{F}}{1.325}=0.755 \mu \mathrm{F}.$ Discussion The total series capacitance $C_{\mathrm{S}}$ is less than the smallest individual capacitance, as promised. In series connections of capacitors, the sum is less than the parts. In fact, it is less than any individual. Note that it is sometimes possible, and more convenient, to solve an equation like the above by finding the least common denominator, which in this case (showing only whole-number calculations) is 40. Thus, \[\dfrac{1}{C_{\mathrm{S}}}=\dfrac{40}{40\mu \mathrm{F}}+\dfrac{8}{40\mu \mathrm{F}}+\dfrac{5}{40\mu \mathrm{F}}=\dfrac{53}{40\mu \mathrm{F}},\] so that \[C_{\mathrm{S}}=\dfrac{40\mu \mathrm{F}}{53}=0.755\mu \mathrm{F}.\] Capacitors in Parallel Figure $\PageIndex{2}$(a) shows a parallel connection of three capacitors with a voltage applied. Here the total capacitance is easier to find than in the series case. To find the equivalent total capacitance $C_{\mathrm{p}}$, we first note that the voltage across each capacitor is $V$, the same as that of the source, since they are connected directly to it through a conductor. (Conductors are equipotentials, and so the voltage across the capacitors is the same as that across the voltage source.) Thus the capacitors have the same charges on them as they would have if connected individually to the voltage source. The total charge $Q$ is the sum of the individual charges: \[Q=Q_{1}+Q_{2}+Q_{3}.\] Using the relationship $Q=CV$, we see that the total charge is $Q=C_{\mathrm{p}}V$, and the individual charges are $Q_{1}=C_{1}V$, $Q_{2}=C_{2}V$, and $Q_{3}=C_{3}V$. Entering these into the previous equation gives \[C_{\mathrm{p}}=C_{1}V+C_{2}V+C_{3}V.\] Canceling $V$ from the equation, we obtain the equation for the total capacitance in parallel $C_{\mathrm{p}}$: \[C_{\mathrm{p}}=C_{1}+C_{2}+C_{3}+\ldots \] Total capacitance in parallel is simply the sum of the individual capacitances. (Again the “ ... ” indicates the expression is valid for any number of capacitors connected in parallel.) So, for example, if the capacitors in the example above were connected in parallel, their capacitance would be \[C_{\mathrm{p}}=1.000\mu \mathrm{F}+5.000\mu \mathrm{F}+8.000\mu \mathrm{F}=14.000\mu \mathrm{F}.\] The equivalent capacitor for a parallel connection has an effectively larger plate area and, thus, a larger capacitance, as illustrated in Figure $\PageIndex{2}$(b). TOTAL CAPACITANCE IN PARALLEL, $C_{\mathrm{p}}$ Total capacitance in parallel $C_{\mathrm{p}}=C_{1}+C_{2}+C_{3}+\ldots$ More complicated connections of capacitors can sometimes be combinations of series and parallel. (See Figure $\PageIndex{3}$.) To find the total capacitance of such combinations, we identify series and parallel parts, compute their capacitances, and then find the total. Example $\PageIndex{2}$:A Mixture of Series and Parallel Capacitance Find the total capacitance of the combination of capacitors shown in Figure $\PageIndex{3}$. Assume the capacitances in Figure $\PageIndex{3}$ are known to three decimal places ( $C_{1}=1.000\mu \mathrm{F},\: C_{2}=5.000\mu \mathrm{F},\: and\: C_{3}=8.000\mu \mathrm{F}$), and round your answer to three decimal places. Strategy To find the total capacitance, we first identify which capacitors are in series and which are in parallel. Capacitors $C_{1}$ and $C_{2}$ are in series. Their combination, labeled $C_{\mathrm{S}}$ in the figure, is in parallel with $C_{3}$. Solution Since $C_{1}$ and $C_{2}$ are in series, their total capacitance is given by $\dfrac{1}{C_{\mathrm{S}}}=\dfrac{1}{C_{1}}+\dfrac{1}{C_{2}}+\dfrac{1}{C_{3}}$ are in series, their total capacitance is given by \[\dfrac{1}{C_{\mathrm{S}}}=\dfrac{1}{C_{1}}+\dfrac{1}{C_{2}}=\dfrac{1}{1.000\mu \mathrm{F}}+\dfrac{1}{5.000 \mu \mathrm{F}}=\dfrac{1.200}{\mu \mathrm{F}}.\] \[C_{\mathrm{S}}=0.833\mu \mathrm{F}.\] This equivalent series capacitance is in parallel with the third capacitor; thus, the total is the sum \[C_{\mathrm{tot}}=C_{\mathrm{S}}+C_{\mathrm{S}}\] \[=0.833\mu \mathrm{F}+8.00\mu \mathrm{F}\] \[=8.833\mu \mathrm{F}.\] Discussion This technique of analyzing the combinations of capacitors piece by piece until a total is obtained can be applied to larger combinations of capacitors. Summary - Total capacitance in series $\dfrac{1}{C_{\mathrm{S}}}=\dfrac{1}{C_{1}}+\dfrac{1}{C_{2}}+\dfrac{1}{C_{3}}+\ldots$ - Total capacitance in parallel $C_{\mathrm{p}}=C_{1}+C_{2}+C_{3}+\ldots$ - If a circuit contains a combination of capacitors in series and parallel, identify series and parallel parts, compute their capacitances, and then find the total.	1,379	common-pile/libretexts_filtered	https://phys.libretexts.org/Bookshelves/College_Physics/College_Physics_1e_(OpenStax)/19%3A_Electric_Potential_and_Electric_Field/19.06%3A_Capacitors_in_Series_and_Parallel	libretexts	libretexts-0000.json.gz:654	https://phys.libretexts.org/Bookshelves/College_Physics/College_Physics_1e_(OpenStax)/19%3A_Electric_Potential_and_Electric_Field/19.06%3A_Capacitors_in_Series_and_Parallel
kBw1wjTD2zUuoYEz	Introduction to Psychology & Neuroscience - MUN Edition	Summary for Personality What Is Personality? Personality has been studied for over 2,000 years, beginning with Hippocrates. More recent theories of personality have been proposed, including Freud’s psychodynamic perspective, which holds that personality is formed through early childhood experiences. Other perspectives then emerged in reaction to the psychodynamic perspective, including the learning, humanistic, biological, trait, and cultural perspectives. Freud and the Psychodynamic Perspective Sigmund Freud presented the first comprehensive theory of personality. He was also the first to recognize that much of our mental life takes place outside of our conscious awareness. Freud also proposed three components to our personality: the id, ego, and superego. The job of the ego is to balance the sexual and aggressive drives of the id with the moral ideal of the superego. Freud also said that personality develops through a series of psychosexual stages. In each stage, pleasure focuses on a specific erogenous zone. Failure to resolve a stage can lead one to become fixated in that stage, leading to unhealthy personality traits. Successful resolution of the stages leads to a healthy adult. Neo-Freudians: Adler, Erikson, Jung, and Horney The neo-Freudians were psychologists whose work followed from Freud’s. They generally agreed with Freud that childhood experiences matter, but they decreased the emphasis on sex and focused more on the social environment and effects of culture on personality. Some of the notable neo-Freudians are Alfred Adler, Carl Jung, Erik Erikson, and Karen Horney. The neo-Freudian approaches have been criticized, because they tend to be philosophical rather than based on sound scientific research. For example, Jung’s conclusions about the existence of the collective unconscious are based on myths, legends, dreams, and art. In addition, as with Freud’s psychoanalytic theory, the neo-Freudians based much of their theories of personality on information from their patients. Learning Approaches Behavioural theorists view personality as significantly shaped and impacted by the reinforcements and consequences outside of the organism. People behave in a consistent manner based on prior learning. B. F. Skinner, a prominent behaviourist, said that we demonstrate consistent behaviour patterns, because we have developed certain response tendencies. Mischel focused on how personal goals play a role in the self-regulation process. Albert Bandura said that one’s environment can determine behaviour, but at the same time, people can influence the environment with both their thoughts and behaviours, which is known as reciprocal determinism. Bandura also emphasized how we learn from watching others. He felt that this type of learning also plays a part in the development of our personality. Bandura discussed the concept of self-efficacy, which is our level of confidence in our own abilities. Finally, Rotter proposed the concept of locus of control, which refers to our beliefs about the power we have over our lives. Humanistic Approaches Humanistic psychologists Abraham Maslow and Carl Rogers focused on the growth potential of healthy individuals. They believed that people strive to become self-actualized. Both Rogers’s and Maslow’s theories greatly contributed to our understanding of the self. They emphasized free will and self-determination, with each individual desiring to become the best person they can become. Biological Approaches Some aspects of our personalities are largely controlled by genetics; however, environmental factors (such as family interactions) and maturation can affect the ways in which children’s personalities are expressed. Trait Theorists Trait theorists attempt to explain our personality by identifying our stable characteristics and ways of behaving. They have identified important dimensions of personality. The Five Factor Model is the most widely accepted theory today. The five factors are openness, conscientiousness, extroversion, agreeableness, and neuroticism. These factors occur along a continuum. Cultural Understandings of Personality The culture in which you live is one of the most important environmental factors that shapes your personality. Western ideas about personality may not be applicable to other cultures. In fact, there is evidence that the strength of personality traits varies across cultures. Individualist cultures and collectivist cultures place emphasis on different basic values. People who live in individualist cultures tend to believe that independence, competition, and personal achievement are important. People who live in collectivist cultures value social harmony, respectfulness, and group needs over individual needs. There are three approaches that can be used to study personality in a cultural context: the cultural-comparative approach, the indigenous approach, and the combined approach, which incorporates both elements of both views. Personality Assessment Personality tests are techniques designed to measure one’s personality. They are used to diagnose psychological problems as well as to screen candidates for college and employment. There are two types of personality tests: self-report inventories and projective tests. The MMPI is one of the most common self-report inventories. It asks a series of true/false questions that are designed to provide a clinical profile of an individual. Projective tests use ambiguous images or other ambiguous stimuli to assess an individual’s unconscious fears, desires, and challenges. The Rorschach Inkblot Test, the TAT, the RISB, and the C-TCB are all forms of projective tests. Here at MUN While there are no researchers in MUN’s Psychology Department whose research focuses solely on personality traits or development, many researchers use personality variables in their research. For example, clinical researchers, such as Drs. Nick Harris and Jacqueline Carter-Major may be interested in whether specific personality profiles make a person susceptible to addictions and eating disorders, respectively.	1,142	common-pile/pressbooks_filtered	https://caul-cbua.pressbooks.pub/psychneuro/chapter/summary-for-personality/	pressbooks	pressbooks-0000.json.gz:80927	https://caul-cbua.pressbooks.pub/psychneuro/chapter/summary-for-personality/
-r_m14Yz-ouWdnRg	19.4: Indigenous Agency and Rights	19.4: Indigenous Agency and Rights - - Last updated - Save as PDF - Jennifer Hasty, David G. Lewis, & Marjorie M. Snipes - OpenStax Learning Objectives By the end of this section, you will be able to: - Explain the significance of Indigenous peoples being declared “domestic dependent nations” in the United States. - Discuss Indigenous rights to natural resources and the degree to which Native nations have been successful in asserting these rights. - Describe some traditional techniques used by Indigenous peoples to create cultural objects as well as efforts to restore this knowledge. - Articulate two features of Indigenous philosophies and worldviews and explain how researchers access Indigenous philosophies and worldviews. - Describe political responses to federal government policies pertaining to Indigenous peoples in the United States. - Articulate Indigenous critiques of the use of Indigenous names and images as mascots for sports teams. Treaties and Removal In the mid-19th century, the United States federal government shifted its approach toward purchasing tribal lands rather than conquering Indigenous nations. Many Native societies had already suffered greatly due to White settlement and were ready to sign treaties that would guarantee them protection on federal Indian reservations . Population loss caused by epidemic disease also played a role in many tribes’ decisions to sign treaties with the federal government. Those who signed treaties received payment for lands, money for schools, and support in establishing Western farming practices in addition to land allotments on a reservation where federal authorities were to guarantee their safety. As White settlement expanded into the western United States, Indigenous peoples both on and off federal reservations were subject to waves of removal from their lands. Areas set aside for reservations that had once seemed undesirably remote for White settlement became increasingly desirable as the White population grew. In the 1830s, tribal peoples living on reservations east of the Mississippi River were forced to move to what is now Oklahoma, then called Indian Territory. The tribes were promised that they would be able to keep their new reservation lands in perpetuity. However, when political currents changed, largely due to the pressures of European immigrants moving westward who desired land for settlement, the land formerly designated Indian Territory was opened to White settlement, and reservations diminished. The most famous Native removal was the Cherokee Trail of Tears in 1838. After President Andrew Jackson signed the Indian Removal Act in 1830, the US Army forced an estimated 16,000 Cherokee then living in the southeast United States to walk to Indian Territory. An estimated 5,000 of these people died on the trail. The Cherokee Trail of Tears was not the only removal. Each time the United States expanded its borders into Indian Territory, tribes were forced to move to smaller reservations with less desirable, resource-poor lands. The Choctaw were removed from Florida to Oklahoma in 1831, and the Creek were removed in 1836, leading to an estimated 3,500 of their 15,000 people dying. Twenty years later, the United States assumed sole title to the lands of the Oregon Territory and removed 4,000 Native people from some 60 different tribes onto two reservations, the Coast and Grand Ronde Reservations. During the western Oregon “Trails of Tears,” members of tribes then living on the temporary Table Rock and Umpqua Reservations were forced to walk more than 300 miles in the dead of winter to the Coast and Grand Ronde Reservations, with many dying from exposure. Once at the Coast and Grand Ronde Reservations, the tribes were made to live with many other tribes from five different language families and to join as one tribe on the reservations. In all parts of the United States, life on the reservations was very challenging. Native peoples had to build their own houses and establish means of producing food and other necessities with limited resources. Federal aid, although guaranteed in the treaties, was slow to arrive and sometimes lost in transit or simply missing. For the first 20 years of the Grand Ronde Reservation, residents lived in poverty with inconsistent food and health care and poorly planned schools. On Oregon reservations, the tribal peoples did not receive their treaty rights of individual plots of farmland until at least 1873. While the government had guaranteed food, by 1860, it was clear that federal officials could not be counted on for regular food shipments. Thousands of Native people died at early ages in the first two decades due to malnutrition and newly introduced diseases. Similar stories can be told for all tribes in the United States. Problems were also caused by untrained, unqualified, and corrupt government officials who stole food, money, and supplies. Domestic Dependent Nations The legal status of Native nations was greatly influenced by several paternalistic rulings by the US Supreme Court in the 1830s. Three rulings known as the Marshall court trilogy ( Johnson v. M’Intosh , 1823; Cherokee Nation v. Georgia , 1831; Worcester v. Georgia , 1832) determined that tribal peoples were domestic sovereign nations within the United States and dependent on the federal government to guarantee their sovereignty. These rulings meant that all reservations were “federal lands,” not part of the states, with the federal government as the administrator. Native rights, therefore, must be given through federal authorities or named in treaties with the federal government. This state of dependency has caused much consternation among Native peoples ever since. As “domestic dependent nations,” many aspects of tribal societies—including management of money, land, education, health care, and other programs—have been administered by the federal government. Beyond the question of the appropriateness of this arrangement, there have been innumerable documented cases of Native peoples not receiving the services or funds they were promised. Between 1910 and the 1980s, Native peoples filed hundreds of civil cases against the federal government for mismanagement of service, land, and money. By the 1940s, there were so many cases that the federal government established a special jurisdictional court, the Indian Claims Commission, to deal with the volume of lawsuits. Under the Indian Claims Commission, many cases were consolidated to make the process more efficient. Originally planned to exist for 10 years, the court was extended into the 1970s, as hundreds of cases had been filed and it was taking decades to decide many of them. The Klamath tribe, for example, filed seven Indian Claims lawsuits for mismanagement of the money they earned through logging operations. The Klamath cases were combined and decided in the 1950s, with some payouts from their lawsuits extending into the 1960s. The Indian Claims Commission ended in 1978, having cleared 546 dockets and named 342 awards totaling $818,172,606.64. One example of a successful Indian Claims case (number K-344) involved California tribal members of groups called the Mission Indians and other tribes from Northern California. These tribes had signed 18 treaties with the federal government in 1851. The treaties were never ratified, and as such, the tribes were never paid for their lands. After the treaties were found hidden in the vast record collections of the National Archives in 1905, the California tribes began working on a case for payment for the lands, for which they filed suit in 1928. The first case was not decided until 1942, with the court declaring that “the Indians of California consist of wandering bands, tribes, and small groups, who had been roving over the same territory during the period under the Spanish and Mexican ownership, before the [1848] treaty between Mexico and the United States whereby California was acquired by the United States” (Indians of California ex rel. U. S. Webb v. United States, 98 Ct. Cl. 583, 1942) This decision meant that the tribes were determined not to have a case for the return of lands and could only ask for cash payments. A second case was decided in 1964. Payments from both cases did not come until 1969, when the court gave the tribes 47 cents per acre for the 64 million acres of California lands they had once occupied, a total of $29.1 million. Court awards were subject to political maneuvering and arbitration within the House of Representatives over how much the tribes would actually receive. In the case of K-344, the award amount was based on the value of the lands in 1851, which had skyrocketed in value over the more than a century that had passed. Many tribal members were very upset by the paltry sum awarded for the wealthy lands of California. Water, Fishing, and Agency From the 1960s to the 1980s, an issue of particular concern to the tribes of the northwestern part of the United States was fishing rights. The “fishing wars” were a series of political and legal battles over whether Indigenous peoples had the right to fish in their usual and accustomed places, as promised in numerous treaties. Following the Belloni ( Sohappy v. Smith/United States v. Oregon , 1969) and Boldt ( United States v. Washington , 1974) court decisions, the tribes of Washington State, including those that had been terminated and not yet restored, maintained their rights to fish in their usual and accustomed ways—and their right to half the catch in the state of Washington. These decisions affirmed tribal sovereignty rights promised in ratified treaties but had the negative consequence of causing delays in the restoration of other tribes from termination. Many sport fishermen’s organizations feared that an increase in restored tribes would impact fishing for non-Natives. Both the Siletz and Grand Ronde tribes experienced delays related to fears about fishing in their federal restorations in the 1970s and 1980s. Ultimately, both tribes were forced to give up fishing and hunting rights to become federally restored. Ironically, neither the Grand Ronde nor the Siletz have fishing or hunting rights in their ratified treaties. Both tribes concluded that restoration of the tribal governments was more important than holding out for fishing and hunting rights. The Klamath tribe of Oregon was terminated in the 1950s, along with tribes in California, including the Karuk and Yurok, all of whom traditionally relied on fish from the Klamath River. In the 1970s and 1980s, these tribes were restored by the US federal government with their rights intact. The Klamath tribe of Oregon is the only tribe on the river with a ratified treaty that guaranteed fishing rights. During the termination period, the federal government had built numerous dams and water reclamation projects on the river and given away water resources to farmers and ranchers in the area. Dams such as the Shasta Dam had destroyed many salmon runs, and the water giveaways had taken much-needed in-stream flows out of the river, making the river warmer and less environmentally friendly to fish. When local tribes were restored, they began demanding rights to fish the river again. These rights were decided in a series of court decisions determining that the Klamath tribe’s water rights preceded those of farmers and municipalities, meaning that their rights to in-stream flows needed to be upheld. Numerous projects are underway to eliminate the dams on the Klamath River and return it to its original state. Tribes with fishing rights in their treaties are now encroaching on the territories of tribes without such rights, leading to legal and political maneuvering between tribes. In Oregon, the Grand Ronde tribe was forced to purchase land at a key fishing location, Willamette Falls, and had to sidestep federal permissions, working with the state to gain “ceremonial” rights. Ultimately, the intertribal conflicts are caused by tribal adherence to federal bureaucratic processes that rely on legal or political channels to resolve problem rather than traditional tribal methods that bring people to the table to form agreements under traditional protocols. Culture and Language Native languages are the most threatened part of the cultures of Native peoples. Many tribes now have only a handful of people who fluently speak the tribe’s language. Of the estimated 10,000 languages once spoken worldwide, at least half have now gone extinct with no speakers, and there are 3,018 Indigenous languages spoken worldwide that are today endangered. One assessment of the 115 Indigenous languages currently spoken in the United State rates two as healthy, 34 as in danger, and 79 likely to go extinct within a generation (Nagle 2019). The rate and severity of language loss is connected to the remaining population of the tribe, whether the tribe has a functioning cultural center, and whether the language continues to be spoken in the households of tribal members. In large part, tribal people of the United States are becoming English-only speakers (Crawford 1995). Language recovery and revitalization have become a focus of many Indigenous peoples. Many tribal members consider knowledge of their language to be the true determinant of tribal identity. Complex understandings of philosophies and lifeways are embedded in language. In addition, tribes believe that their ancestors’ spirits visit members of the tribe to speak with and advise them, and if a person does not know the language, they will not be able to understand them. Tribes are now working to restore, preserve, stabilize, and teach their languages to the next generations to preserve their knowledge and cultural identities. The University of California, Berkeley, developed a master-apprentice program that is helping many Indigenous groups develop more language speakers by partnering fluent speakers with young tribal members. Even with this type of training, it can take years to learn to fluently speak the language. Another approach is the language immersion program, inspired by Hawaiian and Maori educational models. The immersion model places students in immersive classrooms for a period of several years, in which only the Native language is spoken. Evening classes are also offered for adult learners. In addition to efforts to restore Native languages, many tribes and urban tribal organizations offer cultural education classes to teach traditional skills. Art and craft classes are quite popular. Classes offered by Native instructors teach traditional techniques for making bows and arrows, weaving baskets, drawing in traditional styles, beading, and making moccasins, among others. History is another area that is receiving some attention. As just one example, the Cherokee Nation has instituted a history program for tribal members and tribal government staff so that all people working with and for the tribe have a shared understanding of history. Finally, Native events and celebrations typically draw substantial crowds. Many tribes and organizations host events such as powwows and tribal dances annually. These events are free to attend and present many different styles of dance and drum music, along with the opportunity to shop for Native arts and crafts. Powwows are usually multi-tribal events, in part reflecting the origin of these events in intertribal boarding schools. Tribal cultures and languages are a deep part of Native identity. There was a time in the United States when Native people were heavily exposed to assimilation pressures. During this time, many Native people stopped identifying as Native and did not teach their language or culture to their children or grandchildren. Acceptance of Native peoples has now shifted in most regions of the United States, and Indigenous peoples do not experience as much overt racism as they have in the past, although there are still some areas in the United States—many on the borders of tribal reservations—where overt racism against Indigenous peoples persists (Ashley 2015). Many of the descendants of once reservation-bound tribes are now actively seeking to reassociate themselves with their tribal cultures, recognizing this part of their heritage as a central part of their identity. Traditional Material Culture The traditional material cultures of Indigenous peoples showcase an impressive array of styles and skills. Native art was heavily collected by individuals and museums in the 19th century, when there were fears that Indigenous cultures were disappearing. Native art remains popular today. While many Indigenous artists continue to work in traditional styles, some are also incorporating contemporary styles and techniques. Native material cultures embed much cultural philosophy. As anthropologist and museum director Nancy Parezo says, “To anthropologists, Native American/First Nation arts are windows to understanding other cultures and societies. They can be specimens used to support evolutionary theories or explain the maker’s cultural concepts of beauty—to show universal concepts and cultural differences, shared meanings, and modes of communication” (1990, 12). Artistic styles such as petroglyphs , in which images are carved into stone, and pictographs , or drawings, can be appreciated as both historic and spiritual statements. The petroglyph site in Cascadia Cave, near Sweet Home, Oregon, has hundreds of carvings. The most easily recognizable are the bear paws on the wall of the cave. There are also numerous lines, zigzags, and holes carved out of the cave wall. Willamette Forest Service archaeologist Tony Farque noted that people had long thought that the place was used to gain “bear power” for Native shamans. However, when one steps back, it is apparent that the decorated area of the wall is bordered by a large relief of a salmon, with one hole as its eye and the carved lines creating gills. The cave is now understood as a site where Indigenous peoples—Kalapuya, Molala, and other tribes in the region—sought to gain power when fishing in the nearby South Fork Santiam River, where salmon were known to spawn. Cultural sites such as Cascadia Cave are in danger of being destroyed by too much attention from archaeologists and the public. For more than a century, Cascadia Cave has been visited by thousands of tourists who have touched the walls, dug in the ground in search of artifacts, taken rubbings of the carvings, and sometimes even carved their initials or painted over petroglyphs to make them stand out more. All these activities degrade the site. Early archaeologists did much the same, digging into the ground and moving many yards of dirt, which has caused rainfall to pool at the walls of the cave. The pooling moisture accelerates the growth of mosses and other plants, which also degrade the walls of the cave. Digging also destroys the archaeological context of the site. It is important to note that in many countries, including the United States, it is illegal to dig up and remove archaeological materials. Those who continue to dig up materials for private collection or for sale are conducting illegal activities. Many of the sites illegally dug are cemetery sites, containing the remains of people and cultural artifacts that are related to descendant tribal populations today. Weaving arts are another significant aspect of material culture for many Indigenous peoples. Basketry techniques were and still are used to construct vessels used for regular household and resource-gathering activities. Indigenous groups developed various techniques for weaving, such as right twist, left twist, overlay, and false embroidery. These techniques result in decorative styles unique to individual tribes. Weaving techniques make use of many natural materials. Large objects such as mats were typically made with cattail and tule, while baskets could be made from a wide variety of materials, including juncus, hazel branches, cedar bark, bear grass, spruce roots, willow, and maidenhair fern. Some materials were chosen for their stability and durability, others for their flexibility, and still others for their color and luster. Dyeing weaving materials created complex color variations. Baskets were even used for cooking. The technique for boiling water in a basket is similar across many cultures: the basket would be tightly woven, normally with a double weave, and then filled with water. The fibers of the basket and the tight weave created a watertight exterior; additionally, some traditions coated the fibers with grease or pitch. Hot rocks, heated in a fire, would be placed in the basket to make the contained liquid boil. In this manner, food could be cooked without destroying the basket. Many tribes now offer classes to teach people the basic techniques and styles particular to their tribal heritage. The Confederated Tribes of Grand Ronde offer classes in carving, weaving arts, beading, regalia making, drum making, and other arts associated with the 27 tribes that make up the confederation. Arts and crafts are intermixed with education about Native philosophy, spirituality, and language. Some people attend classes for years to master the art style they enjoy, and tribal members may apprentice with master artisans to learn more advanced techniques. Many artisans are creating works of art that are inspired by deep feelings of Native identity, using their art to define themselves and their people within the contexts of both the present and the past. Several artists have become professionals and are producing work for galleries, exhibits, exterior monuments, and contracted sales. The artists employ traditional arts as well as contemporary sculptures and artistic traditions such as painting, drawing, and illustration. Many traditional three-dimensional artworks, such as cedar statues, are now rendered in metal, stone, or even glass so that they are more durable and can survive the rigors of contemporary tourism. Indigenous Philosophy and Worldviews A shared element of Indigenous philosophy across various cultures is the conception of humans existing in relationship to the world around them. Native peoples believe they are deeply connected to the natural world; animals are viewed as relatives, and plants, rocks, and mountains are all understood to have animistic spirits. Rivers, lakes, and even the seasons themselves are also understood as having spirits. Many Native American peoples believe that animals were once their brothers and sisters. It is believed that from the actions of some of the godlike animals, such as Coyote, Beaver, and Raven, much of the world was made. Many Native peoples gain shamanic powers by forming close relationships with certain animals. These powers might include the ability to heal, to poison, to call salmon, to call weather, to fish, or to communicate with animals. Typically, these abilities are gained through ceremonies designed to familiarize people with their spirit helpers at a young age. Ceremonies differ, but a common format involves a youth going off by themselves into a special natural area—such as a forest, hilltop, or mountain cave—and fasting and meditating until they hear their helper spirit. In this manner, many Native peoples are connected to spiritual powers; the most powerful may become a shaman or spiritual leader of their tribe. Details of these types of ceremonies are kept secret within each tribe. One reason for this secrecy is a concern that non-Native people might attempt the same ceremonies without guidance and perhaps hurt themselves or the world around them in the process. Native philosophy is understood to be embodied in the elders of the tribes. By living a full life within their particular cultural context, tribal elders gain wisdom about their people and culture. Many maintain tribal languages, too. Elders are honored and supported by younger members of their societies, who in turn learn about tribal traditions and philosophies from the elders. Elders come to their position partly through age, but normally they are recognized by their tribes when they exhibit great wisdom. Certain elders may have greater status than others depending on how well versed they are in their traditions and how respected they are by the community. Native philosophy can also be gleaned through the study of oral histories. Many oral histories relate to subjects such as how the world was formed, how humans relate to animals, and how to acquire food, offering moral and ethical lessons. Oral histories may also be records of historic events, such as when the tribe was removed to a reservation, when many people died from disease, when a tsunami forced the people to escape to a mountain, when the land was changed by geological activity, or when there was a war. Oral histories are often full of metaphors and symbols of powerful spiritual forces that caused the event. One example is the story told by the Wasco people of when Coyote and Wishpoosh (Beaver) fought on the Columbia River and created the Columbia Gorge. This oral history reflects Native explanations of a series of flood events that occurred when rushing floodwaters carved out the Columbia Gorge in Oregon. The Missoula floods occurred from 18,000 to 15,000 years ago during the large Ice Age. The floods, perhaps as many as 90 of them, are noted by geologists to have been caused by the breaking of glacial ice dams behind which was Lake Missoula. During fluctuations in the warming period, the ice dams burst, and millions of hectares of water from the glacial lake flooded down the Columbia to carve out the Columbia River Gorge. The dams would refreeze and burst again, perhaps hundreds of times, to scour the lands east of the Columbia of topsoil and carve out the gorge. The topsoil would be deposited in the Willamette Valley (Allen, Burns, and Burns 2009). It is remarkable that Native peoples maintained oral histories documenting this event for at least 15,000 years. The Wasco oral history of Wishpoosh and Coyote is only one such story of this event. All tribes in the region have a story that mentions a flood of this magnitude. Indigenous worldviews are embedded in ceremonies as well. The Tolowa Nation of Northern California practices Nee-dash, their world renewal ceremony, also called the Feather Dance, on the winter and summer solstices. This ceremony lasts as long as 10 days and is meant to showcase the wealth of the tribe. Dancers, both men and women, wear regalia and dance continuously for the 10 days of the ceremony. Each day, they increase the number of necklaces they wear and the wealth displayed in their regalia. When the dancers become “wealthier,” it is a metaphor for the growth of food, understood as the wealth of the land, that begins in the spring of each year. Dancers move in a semicircle, men on one side and women on the other, as a leader sings Native ceremonial songs and stamps out a beat on the hard-packed earthen floor with a tall stamper stick. Dancers take turns “coming out” and dancing, individually or in twos, threes, or larger groups, understood to be displaying their ceremonial power in hunting, fishing, or gathering. An audience of tribal people is normally situated around the benches of the dance house, men on one side and women on the other. The dances are meant to renew the earth to ensure strong returns of seasonal fish runs, good hunting opportunities, and rich yields of acorns or berries. The ceremony honors the land, the animals, and the plants that sustain the people. This ceremony establishes a spiritual relationship in which people are not separate from nature but a part of it, with the responsibility to act as stewards of its great wealth. Most Indigenous cultures have ceremonies similar to this, centered on events such as the first salmon catch, the first hunt, or the first gathering of any important food. First salmon ceremonies for the Takelma peoples of the Rogue River Valley in Oregon involve a young man taking the bones of the first salmon caught that year down to the bottom of the Rogue River. These ceremonies are an important way for Native peoples to acknowledge and recommit themselves to a responsibility to steward the natural world in order to sustain its health and vibrancy so that the people who rely on it may thrive into the future. Indigenous Critique: Rights, Activism, Appropriation, and Stereotypes In the contemporary era, the publications of academics have had a great deal of influence on how tribes have been treated by the federal government and other groups. A 1997 essay, titled “Anthropology and the Making of Chumash Tradition,” included the authors’ opinion that the Coast Chumash tribe were descendants of Mexican people, and not Native people of North America at all (Haley and Wilcoxon 1997). The essay relied in part on rumors that were later refuted as unproven by archaeologist Jon Erlandson (1998). These claims, even disproven, aided other Native peoples in accusing the Coast Chumash of not being Native, resulting in many social and political problems for the community. Scholarly publications such as these can affect the ability of tribal nations in the United States to gain federal recognition status because all applicants for federal recognition must establish continuous culture and governance. Public and scholarly opinions can have a huge effect on whether tribes get recognized and are able to restore their culture and sovereignty after centuries of colonization. Responses to the disempowering effects of colonialism have sometimes been overtly political. In the 1960s, the American Indian Movement (AIM) took actions to bolster tribal sovereignty throughout the United States. AIM was involved with several highly public activities, including an occupation at Mount Rushmore in 1971 in protest over the illegal taking of Sioux lands and the carving of presidents’ faces in a mountain sacred to the Sioux. AIM also participated in the occupation of Wounded Knee in 1973, the site of a historic battleground, in protest over the failure to impeach Oglala Sioux president Richard Wilson; the resulting standoff with federal law enforcement lasted 71 days. Public awareness of the federal government’s oppression of Native peoples grew when a large military force was deployed during a second occupation of Wounded Knee, an event called Wounded Knee 2. AIM’s work was part of a larger civil rights movement that involved Black, Latina/Latino, and women activists as well as the growing anti–Vietnam War movement. This larger movement created political shifts in the United States that benefited Native communities (Johansen 2013). Beginning in the 1970s, several laws were passed by Congress to empower tribes. These included policies pertaining to education (Indian Education Act, 1972), child foster care (Indian Child Welfare Act, 1978), college education (Tribally Controlled Colleges and Universities Assistance Act, 1978), freedom of religion (American Indian Religious Freedom Act, 1978), and rights to archaeological sites and remains (Archaeological Resources Protection Act, 1979, and Native American Graves and Repatriation Act, 1990). This period also saw the end of the national policy of termination and a turn toward allowing tribes that had been terminated to be restored, with self-determination becoming standard federal policy. Stereotypes Native peoples have also become vocal in confronting stereotypes about them. The first Western stereotypes of Native peoples in North American depicted them in primitivist terms as noble savages , living in harmony with nature, with no notions of laws, time, or money. Implicit in this view was the idea that Indigenous peoples were not fully civilized and did not deserve the same rights as White, Christian people. Their land could thus be taken away. This stereotype has been described by writer Albert Memmi “as a series of negations: they were not fully human, they were not civilized enough to have systems, they were not literate, their languages and modes of thought were inadequate” (Smith 2021, 31). Throughout the history of the United States, these stereotypes have been used to progressively take more and more away from Native peoples. When reservations were first established, they were said to be permanent homes, but as White settlers began to see these lands as attractive places, the notion was again raised that Native peoples were not using the land appropriately. Additional stereotypes originated with early anthropological research. Notions that Native peoples could not digest alcohol, were lazy and would not work, were not intelligent enough to become civilized, or were dying off as a population because they did not have a civilized culture have all been perpetuated by scholars who embraced social evolutionary theories about human societies. The idea that societies and civilizations existed in competition with one another, and that Native peoples were not competitive because they were savages or barbarians, was inspired by Lewis Henry Morgan’s proposal of a hierarchy of civilizations. These ideas have been heavily refuted, but the stereotypes persist and continue to affect Native peoples in prejudicial ways. Recently, the issue of Indian mascots has received a lot of attention. In the early 20th century, private and professional sports teams and franchises begin to name their athletic teams after Native groups or some characteristic words referring to Native peoples. Common names include the Warriors, Chiefs, Indians, Reds, Redskins, and Braves. Some of these names may have been chosen to honor the strength and resilience of people who had survived centuries of war with colonizing peoples. Regardless of the original intention, as time went on, fans of many of these teams developed practices that disparaged Indigenous peoples. Many mascots were cartoonish or savage caricatures. These mascots may have been the only exposure many American people had to Native peoples, at a time when there was no valid education about Native peoples offered in public schools. The first significant challenge to the use of such mascots was led by Charlene Teters, a student at the University of Illinois, against the university’s mascot, Chief Illiniwek, in the 1980s. Teters criticized various aspects of the chief’s presentation, including the headdress, regalia, and dance style, the latter of which was the invention of students who took the role of mascot each year. The campaign against this mascot continued for some 20 years, with many fans and alumni of the university countering that the mascot was meant to honor the Illiniwek people. The mascot was finally dropped by the university in 2007. Much opposition to mascots is connected not to the use of the figure itself but to the behavior of fans. Practices such as dressing in red paint, wearing outfits of fake feathers and fake headdresses, and using arm motions such as the “tomahawk chop” to show team spirit have offended Native groups. Names might also carry meanings not fully understood by fans. Controversy around the Washington Redskins’ name and mascot lasted for some 30 years. Many fans weren’t aware that the term redskins was used in states such as California and Oregon to refer to Native scalps collected by White American militia members. These scalps, or redskins, could be returned to the state government for a bounty. At certain periods in U.S. history, hundreds of Native people were killed, and whole villages sometimes destroyed, by militia seeking redskins to collect these bounties. In 2020, the Washington Redskins dropped the name, becoming known as the Washington Football Team until a replacement name was chosen. Similarly, in 2019, the Cleveland Indians dopped its “Chief Wahoo” mascot, and in 2021, the team changed its name to the Cleveland Guardians. In some cases, tribal nations have collaborated with universities to develop more respectful mascot images. The University of Utah has collaborated with the Ute tribe in designing its mascot image featuring a feather, and Florida State University has worked with the Seminole tribe to develop its Appaloosa horse rider and spear imagery. There remains a political divide in the debate about mascots, with some Native activists believing there should be no Indian mascots, while others think that sovereign tribal nations, as sovereign governments, should be able to decide how their people are characterized by organized athletic organizations.	7,540	common-pile/libretexts_filtered	https://socialsci.libretexts.org/Bookshelves/Anthropology/Introductory_Anthropology/Introduction_to_Anthropology_(OpenStax)/19%3A_Indigenous_Anthropology/19.04%3A_Indigenous_Agency_and_Rights	libretexts	libretexts-0000.json.gz:37700	https://socialsci.libretexts.org/Bookshelves/Anthropology/Introductory_Anthropology/Introduction_to_Anthropology_(OpenStax)/19%3A_Indigenous_Anthropology/19.04%3A_Indigenous_Agency_and_Rights
47YsxmtUdPj46udO	Introduction to Sociology	247 Reading: Urbanization on the Rise Urbanization is the study of the social, political, and economic relationships in cities, and someone specializing in urban sociology studies those relationships. In some ways, cities can be microcosms of universal human behavior, while in others they provide a unique environment that yields its own brand of human behavior. There is no strict dividing line between rural and urban; rather, there is a continuum where one bleeds into the other. However, once a geographically concentrated population has reached approximately 100,000 people, it typically behaves like a city regardless of what its designation might be. The Growth of Cities According to sociologist Gideon Sjoberg (1965), there are three prerequisites for the development of a city: First, good environment with fresh water and a favorable climate; second, advanced technology, which will produce a food surplus to support nonfarmers; and third, strong social organization to ensure social stability and a stable economy. Most scholars agree that the first cities were developed somewhere in ancient Mesopotamia, though there are disagreements about exactly where. Most early cities were small by today’s standards, and the largest was most likely Rome, with about 650,000 inhabitants (Chandler and Fox 1974). The factors limiting the size of ancient cities included lack of adequate sewage control, limited food supply, and immigration restrictions. For example, serfs were tied to the land, and transportation was limited and inefficient. Today, the primary influence on cities’ growth is economic forces. Since the recent economic recession reduced housing prices, researchers have been waiting to see what happens to urban migration patterns in response. Urbanization in the United States Urbanization in the United States proceeded rapidly during the Industrial Era. As more and more opportunities for work appeared in factories, workers left farms (and the rural communities that housed them) to move to the cities. From mill towns in Massachusetts to tenements in New York, the industrial era saw an influx of poor workers into U.S. cities. At various times throughout the country’s history, certain demographic groups, from post-Civil War southern Blacks to more recent immigrants, have made their way to urban centers to seek a better life in the city. Managing Refugees and Asylum-Seekers in the Modern World In 2013, the number of refugees, asylum-seekers, and internally displaced people worldwide exceeded 50 million people for the first time since the end of World War II. Half these people were children. A refugee is defined as an individual who has been forced to leave his or her country in order to escape war, persecution, or natural disaster, while asylum-seekers are those whose claim to refugee status has not been validated. An internally displaced person, on the other hand, is neither a refugee nor an asylum-seeker. The war in Syria caused most of the 2013 increase, forcing 2.5 million people to seek refugee status while internally displacing an additional 6.5 million. Violence in Central African Republic and South Sudan also contributed a large number of people to the total (The United Nations Refugee Agency 2014). The refugees need help in the form of food, water, shelter, and medical care, which has worldwide implications for nations contributing foreign aid, the nations hosting the refugees, and the non-government organizations (NGOs) working with individuals and groups on site (The United Nations Refugee Agency 2014). Where will this large moving population, including sick, elderly, children, and people with very few possessions and no long-term plan, go? Suburbs and Exurbs As cities grew more crowded, and often more impoverished and costly, more and more people began to migrate back out of them. But instead of returning to rural small towns (like they’d resided in before moving to the city), these people needed close access to the cities for their jobs. In the 1850s, as the urban population greatly expanded and transportation options improved, suburbs developed. Suburbs are the communities surrounding cities, typically close enough for a daily commute in, but far enough away to allow for more space than city living affords. The bucolic suburban landscape of the early twentieth century has largely disappeared due to sprawl. Suburban sprawl contributes to traffic congestion, which in turn contributes to commuting time. And commuting times and distances have continued to increase as new suburbs developed farther and farther from city centers. Simultaneously, this dynamic contributed to an exponential increase in natural resource use, like petroleum, which sequentially increased pollution in the form of carbon emissions. As the suburbs became more crowded and lost their charm, those who could afford it turned to the exurbs, communities that exist outside the ring of suburbs and are typically populated by even wealthier families who want more space and have the resources to lengthen their commute. Together, the suburbs, exurbs, and metropolitan areas all combine to form a metropolis. New York was the first U.S. megalopolis, a huge urban corridor encompassing multiple cities and their surrounding suburbs. These metropolises use vast quantities of natural resources and are a growing part of the U.S. landscape. Suburbs Are Not All White Picket Fences: The Banlieues of Paris What makes a suburb a suburb? Simply, a suburb is a community surrounding a city. But when you picture a suburb in your mind, your image may vary widely depending on which nation you call home. In the United States, most consider the suburbs home to upper— and middle—class people with private homes. In other countries, like France, the suburbs––or “banlieues”–– are synonymous with housing projects and impoverished communities. In fact, the banlieues of Paris are notorious for their ethnic violence and crime, with higher unemployment and more residents living in poverty than in the city center. Further, the banlieues have a much higher immigrant population, which in Paris is mostly Arabic and African immigrants. This contradicts the clichéd U.S. image of a typical white-picket-fence suburb. In 2005, serious riots broke out in the banlieue of Clichy-sous-Bois after two boys were electrocuted while hiding from the police. They were hiding, it is believed, because they were in the wrong place at the wrong time, near the scene of a break-in, and they were afraid the police would not believe in their innocence. Only a few days earlier, interior minister Nicolas Sarkozy (who later became president), had given a speech touting new measures against urban violence and referring to the people of the banlieue as “rabble” (BBC 2005). After the deaths and subsequent riots, Sarkozy reiterated his zero-tolerance policy toward violence and sent in more police. Ultimately, the violence spread across more than thirty towns and cities in France. Thousands of cars were burned, many hundreds of people were arrested, and both police and protesters suffered serious injuries. Then-President Jacques Chirac responded by pledging more money for housing programs, jobs programs, and education programs to help the banlieues solve the underlying problems that led to such disastrous unrest. But none of the newly launched programs were effective. Sarkozy ran for president on a platform of tough regulations toward young offenders, and in 2007 the country elected him. More riots ensued as a response to his election. In 2010, Sarkozy promised “war without mercy” against the crime in the banlieues (France24 2010). Six years after the Clichy-sous-Bois riot, circumstances are no better for those in the banlieues. As the Social Policy & Debate feature illustrates, the suburbs also have their share of socio-economic problems. In the United States, white flight refers to the migration of economically secure white people from racially mixed urban areas and toward the suburbs. This occurred throughout the twentieth century, due to causes as diverse as the legal end of racial segregation established by Brown v. Board of Education to the Mariel boatlift of Cubans fleeing Cuba’s Mariel port for Miami. Current trends include middle-class African-American families following white flight patterns out of cities, while affluent whites return to cities that have historically had a black majority. The result is that the issues of race, socio-economics, neighborhoods, and communities remain complicated and challenging. Urbanization around the World During the Industrial Era, there was a growth spurt worldwide. The development of factories brought people from rural to urban areas, and new technology increased the efficiency of transportation, food production, and food preservation. For example, from the mid-1670s to the early 1900s, London’s population increased from 550,000 to 7 million (Old Bailey Proceedings Online 2011). Global favorites like New York, London, and Tokyo are all examples of postindustrial cities. As cities evolve from manufacturing-based industrial to service- and information-based postindustrial societies, gentrification becomes more common. Gentrification occurs when members of the middle and upper classes enter and renovate city areas that have been historically less affluent while the poor urban underclass are forced by resulting price pressures to leave those neighborhoods for increasingly decaying portions of the city. Globally, 54 percent of the world’s 7 billion people currently reside in urban areas, with the most urbanized region being North America (82 percent), followed by Latin America/the Caribbean (80 percent), with Europe coming in third (72 percent). In comparison, Africa is only 40 percent urbanized. With 38 million people, Tokyo is the world’s largest city by population. The world’s most densely populated cities are now largely concentrated in the global south, a marked change from several decades ago when the biggest cities were found in the global north. In the next forty years, the biggest global challenge for urbanized populations, particularly in less developed countries, will be to achieve development that occurs without depleting or damaging the natural environment, also called sustainable development (United Nations, Department of Economic and Social Affairs, Population Division 2014). Think It Over - What are the differences between the suburbs and the exurbs, and who is most likely to live in each? - How will the growth in urban populations affect the world over the next ten years? Practice 1. What are the prerequisites for the existence of a city? - Good environment with water and a favorable climate - Advanced agricultural technology - Strong social organization - All of the above Show Answer d 2. In 2014, what was the largest city in the world? - Delhi - New York - Shanghai - Tokyo Show Answer d 3. What led to the creation of the exurbs? - Urban sprawl and crowds moving into the city - The high cost of suburban living - The housing boom of the 1980s - Gentrification Show Answer a 4. How are the suburbs of Paris different from those of most U.S. cities? - They are connected by public transportation. - There are more industrial and business opportunities there. - They are synonymous with housing projects and urban poor. - They are less populated. Show Answer c 5. How does gentrification affect cities? - They become more crowded. - Less affluent residents are pushed into less desirable areas. - Traffic issues, including pollution, become worse. - All of the above Show Answer b 6. Urbanization includes the sociological study of what? - Urban economics - Urban politics - Urban environments - All of the above Show Answer d Show Glossary - asylum-seekers: - those whose claim to refugee status have not been validated - exurbs: - communities that arise farther out than the suburbs and are typically populated by residents of high socioeconomic status - gentrification: - the entry of upper- and middle-class residents to city areas or communities that have been historically less affluent - internally displaced person: - someone who fled his or her home while remaining inside the country’s borders - megalopolis: - a large urban corridor that encompasses several cities and their surrounding suburbs and exurbs - metropolis: - the area that includes a city and its suburbs and exurbs - refugee: - an individual who has been forced to leave their country in order to escape war, persecution, or natural disaster - suburbs: - the communities surrounding cities, typically close enough for a daily commute - sustainable development: - development that occurs without depleting or damaging the natural environment - urban sociology: - the subfield of sociology that focuses on the study of urbanization - urbanization: - the study of the social, political, and economic relationships of cities - white flight: - the migration of economically secure white people from racially mixed urban areas toward the suburbs	2,658	common-pile/pressbooks_filtered	https://library.achievingthedream.org/mvccintrotosociology/chapter/reading-urbanization/	pressbooks	pressbooks-0000.json.gz:35791	https://library.achievingthedream.org/mvccintrotosociology/chapter/reading-urbanization/
eBoLnsr0Fzxuxc7p	Teaching Apparel Production	44 Magic Pillowcase Sheri Deaton Magic Pillowcase This project combines multiple skills and techniques, making it an excellent assessment for students as they learn to construct apparel. The pillowcases can be modified according to the size of the pillow, giving students another opportunity to practice their altering skills. The magic pillowcase is a favorite project for students in my course, and many students choose to make more than one. Some students will find the process intimidating, but others will jump in and enjoy the challenge. Once students understand the process, they may not want to make a plain pillowcase again. If you are looking for a good community service project, consider having your FCCLA students make these pillowcases and donate them to a local organization working with children in foster care or a shelter for women and children. Degree of difficulty: Easy to Moderate Skills Demonstrated As students complete this project, they are demonstrating their abilities to - Read and follow directions - Measure fabric - Cut fabric - Measure and mark seam allowances - Sew French seam - Trim seam allowances - Clip corners - Turn fabric - Sew straight seams, aligning seams and corners. - Alter pattern, if needed - Problem solve - Think critically Magic Pillowcase Pattern https://www.alandacraft.com/2016/10/25/magic-pillow-case-tutorial/ CTSO Connection The fourth purpose of FCCLA is “to encourage individual and group involvement in helping achieve global cooperation and harmony” (FCCLA, 2019). Embedding community service projects into an apparel production course is an excellent way for students to see how they can use their skills to benefit others in their community. If you are looking for a good community service project, consider having your FCCLA students make these pillowcases and donate them to a local organization working with children in foster care or a shelter for women and children. References Deaton, S. (2021). Teaching Apparel Production. Presentation. Family, Career, and Community Leaders of America (FCCLA). (n.d.). About FCCLA. Family, Career, and Community Leaders of America (FCCLA). Retrieved January 12, 2023, from https://fcclainc.org/about#:~:text=The%20work%20of%20FCCLA%20helps,in%20four%20specific%20Career%20Pathways.	434	common-pile/pressbooks_filtered	https://uark.pressbooks.pub/teachingappareldesign/chapter/magic-pillow-case-teaching-apparel-production/	pressbooks	pressbooks-0000.json.gz:22478	https://uark.pressbooks.pub/teachingappareldesign/chapter/magic-pillow-case-teaching-apparel-production/
3UBM3LOWAufNCcNW	The Book of History (Vol. 1 of 18) A History of All Nations from the Earliest Times to the Present	18) *** [Illustration: IN THE SAURIAN AGE, WHEN THE WORLD’S INHABITANTS WERE GIGANTIC REPTILES] The Book of History A History of all Nations FROM THE EARLIEST TIMES TO THE PRESENT WITH OVER 8000 ILLUSTRATIONS WITH AN INTRODUCTION BY VISCOUNT BRYCE, P.C., D.C.L., LL.D., F.R.S. CONTRIBUTING AUTHORS W. M. Flinders Petrie, LL.D., F.R.S UNIVERSITY COLLEGE, LONDON Hans F. Helmolt, Ph.D. EDITOR, GERMAN “HISTORY OF THE WORLD” Stanley Lane-Poole, M.A., Litt.D. TRINITY COLLEGE, DUBLIN Robert Nisbet Bain ASSISTANT LIBRARIAN, BRITISH MUSEUM Hugo Winckler, Ph.D. UNIVERSITY OF BERLIN Archibald H. Sayce, D.Litt., LL.D. OXFORD UNIVERSITY Alfred Russel Wallace, LL.D., F.R.S. AUTHOR, “MAN’S PLACE IN THE UNIVERSE” Sir William Lee-Warner, K.C.S.I. MEMBER OF COUNCIL OF INDIA Holland Thompson, Ph.D. THE COLLEGE OF THE CITY OF NEW YORK W. Stewart Wallace, M.A. UNIVERSITY OF TORONTO Maurice Maeterlinck ESSAYIST, POET, PHILOSOPHER Dr. Emile J. Dillon UNIVERSITY OF ST. PETERSBURG Arthur Mee EDITOR, “THE BOOK OF KNOWLEDGE” Sir Harry H. Johnston, K.C.B., D.Sc. LATE COMMISSIONER FOR UGANDA Johannes Ranke UNIVERSITY OF MUNICH K. G. Brandis, Ph.D. UNIVERSITY OF JENA And many other Specialists Volume I MAN AND THE UNIVERSE The World before History The Great Steps in Man’s Development Birth of Civilisation and the Growth of Races Making of Nations and the Influence of Nature JAPAN The Country and the People NEW YORK THE GROLIER SOCIETY LONDON THE EDUCATIONAL BOOK CO. EDITORIAL AND CONTRIBUTING STAFF OF THE BOOK OF HISTORY Rt. Hon. Viscount Bryce, F.R.S. Formerly British Ambassador to the United States, Author of “The American Commonwealth” Professor E. Ray Lankester, F.R.S. President British Association, 1906-7; Past Director of South Kensington Museum of Natural History Dr. Alfred Russel Wallace, F.R.S. Co-discoverer with Darwin of the Theory of Natural Selection; Author of “Man’s Place in the Universe” Dr. William Johnson Sollas, F.R.S. Professor of Geology at Oxford University Dr. W. M. Flinders Petrie, F.R.S. Professor of Egyptology, University College, London; Founder of British School of Archæology in Egypt Professor Wm. Boyd Dawkins, F.R.S. Professor of Geology at Victoria University, Manchester; Author of “Early Man in Britain” Frederic Harrison, M.A. Hon. Fellow and formerly Tutor of Wadham College, Oxford; Vice-President of the Royal Historical Society Dr. Archibald H. Sayce Professor of Assyriology at Oxford University Sir Harry H. Johnston, K.C.B. Doctor of Science of Cambridge University; late Commissioner and Consul-General for Uganda Dr. J. Holland Rose Cambridge University Lecturer on Modern History; Author of “Development of the European Nations” Dr. Stanley Lane-Poole Professor of Arabic at Trinity College, Dublin Sir John Knox Laughton Professor of Modern History at King’s College, London University; Editor of Lord Nelson’s Despatches Oscar Browning, M.A. Fellow of King’s College, Cambridge; University Lecturer in History Professor Ronald M. Burrows Professor of Greek at University College of South Wales; Author of “Discoveries in Crete” David George Hogarth, M.A. Director of Cretan Exploration Fund and Past Director of the British School at Athens Herbert Paul, M.P. Author of “A History of Modern England” Sir Robert K. Douglas Professor of Chinese at King’s College, University of London; late Keeper of Oriental Books, British Museum Dr. Hugo Winckler Professor of History and Oriental Languages at the University of Berlin Sir William Lee-Warner, K.C.S.I. Member of the Council of India; Formerly Scholar of St. John’s College, Cambridge Dr. E. J. Dillon Author and Journalist; Master of Oriental Languages at the University of St. Petersburg William Romaine Paterson, M.A. Author of “The Nemesis of Nations” W. Warde Fowler, M.A. Scholar and Fellow of Lincoln College, Oxford; Author of “The City-State of the Greeks and Romans” Dr. H. F. Helmolt Author of “German History” and Editor of the German “History of the World” Professor Konrad Haebler Of the Imperial Library of Berlin Professor Richard Mayr Of the Vienna Academy of Commerce Arthur Mee Editor of The Book of Knowledge. Professor Rudolf Scala Of the Imperial University of Vienna Professor Karl Weule Director of the Leipzig Museum of Anthropology Professor Wilhelm Walther Of the University of Rostock Arthur Christopher Benson, M.A. Fellow of Magdalene College, Cambridge; Editor of The Correspondence of Queen Victoria Major Martin Hume Lecturer in Spanish History and Literature at Pembroke College, Cambridge Robert Nisbet Bain Traveller and Historian; Assistant Librarian at the British Museum Richard Whiteing Author of “The Life of Paris” His Excellency Max von Brandt Ex-German Ambassador to China and Minister in Japan Francis H. Skrine Traveller and Explorer; late of the Indian Civil Service Holland Thompson, Ph. D. The College of the City of New York. Dr. Archdall Reid, F.R.S.E. Author of “The Principles of Heredity” Arthur Diósy Founder of the Japan Society; Author of “The New Far East” Dr. K. G. Brandis Director of the University Libraries at Jena Thomas Hodgkin, D.C.L. Author of “A Political History of England” Professor Joseph Kohler Professor of Jurisprudence at Berlin University Angus Hamilton Traveller and Correspondent in the Far East; Author of “Afghanistan” J. G. D. Campbell, M.A. Late Educational Adviser to the Government of Siam W. R. Carles, C.M.G. Geographer; late British Consul at Tientsin, China Professor Johannes Ranke Professor of Anthropology, Physiology, and Natural History at Munich W. S. Wallace, M. A. University of Toronto. Hon. Bernhard R. Wise Scholar of Queen’s College, Oxford; Ex-Attorney-General of New South Wales K. W. C. Davis, M.A. Fellow of Balliol College, Oxford CONTENTS OF VOLUME I THE SAURIAN AGE FRONTISPIECE FIRST GRAND DIVISION MAN AND THE UNIVERSE PAGE Editorial Introduction 1 Plan of the HISTORY 3 Plan of First Grand Division 6 A View across the Ages 7 Summary of World History 60 Chronology of 10,000 Years 61 Time-table of the Nations 74 Contemporary Figures in History 78 The Beginning of the Earth 79 Four Periods of the Earth’s Development 89 Geological Clock of the World’s Life 90 How Life became possible on Earth 91 Scene from the Prehistoric World Plate facing 96 Beginning of Life on the Earth 99 How Man obtained Mastery of the Earth 108 THE WORLD BEFORE HISTORY Prehistoric Man attacking Cave Bears Plate facing 114 The Wonderful Story of Drift Man 115 The Appearance of Man on the Earth 127 Life of Man in the Stone Age 132 Primitive Man in the Past and Present 145 The Home Life of Primitive Folk 164 When History was dawning 175 THE GREAT STEPS IN MAN’S DEVELOPMENT The Material Progress of Mankind 185 Beginnings of Commerce Plate facing 192 The Higher Progress of Mankind 203 BIRTH OF CIVILISATION AND GROWTH OF RACES Seven Wonders of Ancient Civilisation 225 Rise of Civilisation in Egypt 233 Rise of Civilisation in Mesopotamia 259 Rise of Civilisation in Europe 281 The Triumph of Race 299 Alphabet of the World’s Races 311 Little Gallery of Races 313 Types of the Chief Races of Mankind 349 Ethnological Chart of the Human Race 352 MAKING OF NATIONS AND THE INFLUENCE OF NATURE Birth and Growth of Nations 353 Land and Water and Greatness of Peoples 377 Environment and the Life of Nations 387 The Size and Power of Nations 399 The Future History of Man 404 SECOND GRAND DIVISION THE FAR EAST Map of the Far East 406 Plan of the Second Grand Division 408 Interest and Importance of the Far East 409 JAPAN COUNTRY AND PEOPLE Great Dates in Japan 416 The Empire of the Eastern Seas 417 Map of Japan 432 Qualities of the Japanese People 433 LIST OF SPECIAL PLATES IN THE BOOK OF HISTORY PAGE The Saurian Age Frontispiece, Vol. 1 Scene from the Prehistoric World: Early Ice Age Facing 96 Prehistoric Men Attacking the Great Cave Bears “ 114 The Beginnings of Commerce “ 192 Carrying Off an Emperor Frontispiece, Vol. 2 Buddha, “The Light of Asia” Facing 562 Four Famous Figures in Chinese History “ 754 The Colour of India Frontispiece, Vol. 3 Gems of Indian Architecture Facing 1154 Indian Temples “ 1196 Nineveh in the Days of Assyria’s Ascendancy Frontispiece, Vol. 4 Two Indian Scenes Facing 1364 Spring Carnival at a Tibetan Monastery “ 1436 The Pyramids of Abusir Frontispiece, Vol. 5 Destruction of Jerusalem by the Romans Facing 1860 Palace of an Assyrian King “ 1956 The Sphinx “ 1996 Alexander, the World Conqueror Frontispiece, Vol. 6 The Acropolis of Athens Facing 2504 An Arab Storyteller Frontispiece, Vol. 7 Theodora, the Byzantine Empress Facing 2906 Glimpse of the Life in a Turkish Harem “ 2994 Primitive Justice Frontispiece, Vol. 8 Thaddeus Reyten at the Diet of Warsaw Facing 3282 Roland “ 3484 Prince Arthur and Hubert Frontispiece, Vol. 9 Venerable Bede Dictating His Translation of the Gospel of St. John Facing 3716 “The Vigil”: A Knight of the Middle Ages “ 3788 Alfred, the Hero King of England “ 3834 King John Granting Magna Charta “ 3865 Crusaders Sighting Jerusalem Frontispiece, Vol. 10 Wolsey’s Last Interview with Henry VIII Facing 4168 Charles I on His Way to Execution “ 4340 Charles II Visiting Wren Frontispiece, Vol. 11 Napoleon the Great Facing 4636 “Peace with Honour” Frontispiece, Vol. 12 The French Soldiers’ Unrealised Dream of Victory Facing 5104 Recessional Frontispiece, Vol. 13 The Conqueror’s Gift to London Facing 5464 King Edward VII “ 5614 Clio, “The Muse of History” Frontispiece, Vol. 14 Flags that Fly in the Four Winds of Heaven Facing 5874 Statue of Liberty Frontispiece, Vol. 15 Hope Facing Index LIST OF MAPS APPEARING IN THE BOOK OF HISTORY PAGE The World as Known to its First Historian 8 Shifting of the Centre of the World’s Commerce 28 How the Mediterranean has Given Place to the Atlantic 29 The First Maps 51 Modern Representation of the World 52 The Europeanisation of the World 55 The Shaping of the Face of the Earth 85 How Mountain Ranges were formed 87 Europe Before the British Isles were Formed 118 The Submerged Lands of Europe 119 Europe in the Ice Age 155 Egypt in Three Periods 243 Babylonia 260 Sea Routes of Ancient Civilisation 283 Land Routes of Ancient Civilisation 284 How Civilisation Spread through Europe 359 The Expansion of White Races 361 The Island that Rules the Sea 378 Oceans of the World 383 Effect of Climate on the Course of History 391 Political Expansion 396 Relation of Rivers and Sea to the Civilisation of Countries 397 South America Africa Europe The Far East, and Australia, Oceania and Malaysia 406 The Island Empire of Japan 432 Japan in the Fifth Century 457 Siberia 634 Movement of the Peoples of Siberia 656 Russia’s Advance in Western Asia 676 Growth of Russia in the Far East 677 The Trans-Siberian Line 692 The Chinese Empire 708 Korea and its Surroundings 858 The Malay Archipelago 886 Islands of Oceania 947 New Zealand 986 Australia and Tasmania 1010 Britain Contrasted with Australia 1012 South-east Australia, Indicating Products 1013 Bed of the Pacific Ocean 1102 The Middle East 1120 Modern India 1161 India in 1801 1266 Bed of the Indian Ocean and China Sea 1419 Suez Canal 1434 Mountain Systems In and Around Tibet 1457 The Approach of Lhasa 1505 Early Empires of the Ancient Near East 1562 Later Empires of the Ancient Near East 1563 Ancient Empires of Western Asia 1582 Modern Africa 2001 Races and Religions of Africa 2005 Natural Products of Africa 2009 Basin of the River Nile 2022 Delta of the River Nile 2024 Utica as it Was 2188 The Remains of Utica 2189 Ancient States of Mediterranean North Africa 2191 Niger River and Guinea Coast 2229 Great Britain in South Africa 2322 Basin of the Zambesi 2332 Basin of the Congo 2347 General Map of Europe 2356 Geographical Connection of the Mediterranean Coasts 2373 Ancient Greece 2482 World Empire of Alexander the Great 2561 Italy in the First Century B.C. 2621 The Roman Empire 2738 Origin of the Barbaric Nations 2797 Principal Countries of Eastern Europe 2894 World’s Great Empires Between 777 and 814 A.D. 2934 Turkey and Surrounding Countries in the 14th and 17th Centuries 3082 Historical Maps of Poland and Western Russia 3220 Western Europe in the Middle Ages 4138 Europe During the Revolutionary Era 4636 Modern Europe 4788 Britain’s Maritime Enterprise 5440 The British Empire in 1702 5462 The British Empire in 1909 5463 The Atlantic Ocean 5656 South America in the Sixteenth Century 5915 South America as it is To-day 5983 North Pole, with routes of Explorers 6014 South Pole 6045 North America 6431 [Illustration: THE BOOK OF HISTORY] This is the story of the earth from the first thing we know of it to the time in which we live. It is the story of man from the first thing we know of him to the last thought that the vision of modern science can suggest. There is no need here to discuss the question how far it is possible to write a universal history, or on what lines such a history should proceed. These points may well be left where Lord Bryce leaves them in his introduction to this book. Nor need we consider what history is; the plain man may be left to make up his own mind as to that while the philosophers are making up theirs. A word may be said, however, of the plan and purpose of this work, especially of that distinction of it which is at once the ground of its appeal and its justification. A UNIVERSAL HISTORY OF THE UNIVERSE It is a commonplace to say of a great work that it is unique, and there would at first sight seem to be peculiar presumption in making such a claim for a History of the World. It may be claimed, however, without any fear of contradiction, that this work has no rival in the English language. There have been histories of the world before; there are available in large numbers histories of all countries well worthy of attention; but there is not, and it may be doubted if there has ever been attempted before, a scientific World-History. This work is, as far as it can possibly be in the present state of knowledge, a universal history of the universe. SCIENCE AND HISTORY That is a far reaching claim to make, but a mere glance through the names of those whose services have been enlisted for the work will make its basis clear. The contributors include some of the foremost students of science. Many men of eminence whose names do not usually come into historical works will be found here. Their function may be described as holding the Lamp of Science up to History. It is for these authorities to read the story of the earth and to tell the plain man what they read there, as Turner read the sunset and painted what he saw. The simile is not so unfortunate as it may appear, because, although our canvas has not the same room for the artist’s imagination as Turner’s had, it will probably be admitted that the imagination of the scientist is often nearer to the truth of things than the conventional belief. THE LIFE-STORY OF ALL NATIONS And the scientist will come into our History whenever and wherever science has any light to throw upon its problems. To the creators of this work the world is not merely an aggregation of countries under more or less settled governments, nor is a country merely the seat of a political system. They conceive the earth as a part of the universe, as one world among many; and this is the story of a huge ball flying in space, on which men and women live and move, on which mighty nations rise and rule and pass away, on which great empires crumble into dust. It is the entrancing book of man and the universe, the life-story of all nations. It begins with the beginning; it regards the universe, as modern science has taught us to regard it, as a vast unit, in which the life of man is the ultimate consummation. A history of the world cannot be written in a day. It is like an institution--it must be allowed to grow. It would be a purposeless sacrifice in an undertaking of such magnitude to reject any work of building-up that is available, and this History has a rare privilege in being able to utilise the result of the matchless research, the tireless industry, the unequalled knowledge of Dr. Hans Helmolt and the distinguished staff of scholars and investigators who have been engaged with him for many years in preparing a history of the world on precisely the lines laid down in this work. THE MATERIAL FOR A WORLD HISTORY It would be impossible to exaggerate the value of the elaborate research made for Dr. Helmolt by such of his eminent collaborators as Professor Johannes Ranke, Professor Ratzel, Professor Joseph Kohler, and others whose names stand for foremost authority wherever the value of learning is understood, and it is one of the chief claims of this work to recognition that it has behind it all the material collected by Dr. Helmolt’s staff, with all the judgment and skill of Dr. Helmolt himself in co-ordinating the labour of his assistants. A work so universal in time and place must engage many minds. Behind it there must be the labour and thought of many lives. The materials for a world-history cannot be amassed by one man, cannot be gathered together in the time that it is possible for one man to devote to them. A moment’s reflection reveals the vastness and complexity of the arrangements for such a work, the reaching-out into far corners of the earth, the ransacking of historical libraries and official archives; the placing of the result of all this research into the hands of a hundred trained historians, the analysing, sifting, and editing of each part as if it were in itself a perfect whole. A BOOK OF HUMAN EXPERIENCE All this labour can hardly be measured. And if we add to our reckoning the work of illustrating the world’s history in pictures, the task of finding illustrations where they are rare as precious stones, or of choosing them where their number is bewildering, the labour that a world-history involves is, indeed, incalculable. It can only be accomplished by the co-operation of many minds, working over a long period, drawing upon actual experience in every part of the world. Especially is this so in the present work. There are histories that can be made up from books, but this is not one of them. The BOOK OF HISTORY is not only a great book of human experience, as every history is; it is the _product_ of experience. It could never have been written if the men who write it had not helped to make the history that they write. THE MAKERS OF THE BOOK It is a book of history by writers and makers of history; it is a book of action by men of action; it is a book, that is, by men who know intimately the real life of the world. When Professor Ratzel writes of the making of nations, he writes with perhaps an unequalled knowledge of the conditions that have made for human progress; when Dr. Flinders Petrie writes of Egypt, when Dr. Sayce writes of Assyria, they write with the same authority that Sir Harry Johnston has in writing of those parts of the British Empire that he has helped to govern. The real rulers of the world are not the princes, and among the makers of this book are men who, though the fierce light that beats upon a throne has not beat upon them, have borne the burden of empire and of ruling men. It is the ideal collaboration, that of the brilliant investigator, the scientific interpreter, and the man of affairs, and it makes possible the achievement of a History which we have claimed to be unique. THE WORLD YESTERDAY, TO-DAY & TO-MORROW We have the facts from the pens of the men who have dug them up fresh from the earth itself or who know them from experience; we have them treated by the men who can turn upon them the full light of modern science; we have the world as it moves in our own time described by the men who know it from the centre, and know it therefore best. This is the story of the world, then, yesterday and to-day. And, as history goes on, as to-day becomes yesterday and to-morrow becomes to-day, we shall find in this book a vision of the things that lie before. Out of the deeps of Time came man. Through the mists of Time he grew. Down the ages of Time he goes. Whence he came we guess; how he lives we know; where he goes the wisdom of History does not tell. But the history of the world is young, and young men shall see visions. THE EDITORS THE BOOK OF HISTORY The Life-Story of the Earth and of All Nations TOLD IN SEVEN GRAND DIVISIONS This plan provides a general scheme for the HISTORY, but is not intended for reference. It does not follow that the exact order of countries here given is maintained throughout the volumes. A full index appears at the end of the work I--MAN AND THE UNIVERSE THE WORLD AND ITS STORY A View Across the Ages: Introduction Summary of the History of the World Chronology of 10,000 Years and Chart of Nations MAKING OF THE EARTH AND THE COMING OF MAN The Beginning of the Earth How Life is Possible on the Earth The Beginning of Life on the Earth How Man Obtained the Mastery of the Earth THE RISE OF MAN AND THE EVE OF HISTORY The World Before History The Great Steps in Man’s Development BIRTH OF CIVILISATION & THE GROWTH OF RACES The Beginnings of Civilisation How Civilisation Came to Europe The Triumph of Race An Alphabet of the World’s Races MAKING OF NATIONS & THE INFLUENCE OF NATURE The Birth and Growth of Nations Influence of Land and Water on National History How Nations are Affected by Their Environment The Size and Power of Nations The Future History of Man II--THE FAR EAST The Interest and Importance of the Far East Japan. Siberia. China. Korea Malaysia Philippines. Malay States. Straits Settlements. Borneo. Sarawak. Sumatra. Java. New Guinea, and other Islands of Malay Archipelago Australia New South Wales. Victoria. Queensland. South Australia. West Australia. Tasmania Oceania New Zealand. Fiji. Pitcairn. Hawaii. Samoa. Tonga and other Islands The Influence of the Pacific Ocean in History III--THE MIDDLE EAST The Importance of the Middle East India. Including Ceylon and the Native States Further India. Siam. Annam. Burma. Tonking. Cochin China. Cambodia. Champa The Influence of the Indian Ocean in History Central Asia. Afghanistan. Baluchistan. Turkestan. Thibet IV--THE NEAR EAST The Ancient Empires of Western Asia Babylonia. Assyria. Elam Early Nations of Western Asia Scythia. Sarmatia. Armenia. Syria. Phœnicia. Israel Western Asia from the Rise of Persia to Mohammed Persia. Asia Minor. Syria. Palestine. Arabia. Mediterranean Islands Western Asia from the Time of Mohammed The Saracen Dominion. The Turkish Empire in Asia. Persia. Arabia V--AFRICA Legacy of Ancient Empires to the Modern World Egypt and the Egyptian Sudan North Africa Tripoli. Tunis. Morocco. Algeria and the French Territories. Sierra Leone. Liberia. Gold Coast. Nigeria. German West Africa. Abyssinia. Somaliland. Erythrea. British East Africa. Zanzibar South Africa Native Races. The Portuguese and Dutch in South Africa. British South Africa: Cape Colony. Natal. Transvaal. Orange River Colony. Rhodesia. Congo Free State. Portuguese East Africa. Angola. German East Africa. German South-West Africa. Madagascar VI--EUROPE 1. EUROPE TO THE FALL OF THE ROMAN EMPIRE Mediterranean Influence in the Making of Europe The Ancient Spirit of Greece and Rome Early Peoples of Europe. Ascendancy of the Greeks The Rise of Rome and the World Empire Social Fabric of the Ancient World: Slave States 2. EASTERN EUROPE TO FRENCH REVOLUTION The Byzantine Empire and the Turk in Europe The Middle Peoples Russia, Poland, and the Baltic Provinces The Social Fabric of the Mediæval World: The Twilight of Nations 3. WESTERN EUROPE IN THE MIDDLE AGES A Survey of Western Mediæval Europe The Peoples of Western Europe The Importance of the Baltic Sea The Emerging of the Nations Frankish Dominion and the Empire of Charlemagne. England. Spanish Peninsula. Italy. The Papacy. Scandinavia The Development of the Nations The German or Holy Roman Empire. France. England. Spain and Portugal. Italy. The Papacy. Scandinavia The Crusades. Industry and Commerce 4. WESTERN EUROPE FROM THE REFORMATION TO THE REVOLUTION A Survey of Western Europe The Reformation and Wars of Religion The Age of Louis XIV. From the Peace of Westphalia to the Treaty of Utrecht The Ending of the Old Order From the Treaty of Utrecht to the Revolution The Importance of the Atlantic to the World Powers Religion After the Reformation. Industry and Commerce 5. THE FRENCH REVOLUTION The Revolutionary and Napoleonic Era The Revolution. The Republic at War and the Rise of Napoleon. The Zenith of Napoleon and his Fall Great Britain in the Napoleonic Era 6. THE RE-MAKING OF EUROPE Europe After Waterloo The Triumph of Despotism. The Revolt Against Despotism Europe in Revolution The Second French Republic and the Coup d’Etat. The Uprising of the Little Nations. National Movements in Germany The Consolidation of the Powers Europe and the Second Empire. The Unification of Italy. The Unification of Germany. The Franco-German War Great Britain to 1871. Russia and Turkey to 1871. Europe since 1871 Great Britain. Germany. France. Austria-Hungary. Spain and Portugal. Italy. Russia. Turkey. Switzerland. Greece. Belgium. Holland. Denmark. Norway. Sweden. Bulgaria. Servia. Roumania. Montenegro. Luxemburg. Monaco. San Marino 7. THE EUROPEAN POWERS TO-DAY Europe in Our Own Time Great Britain. Germany. Austria-Hungary. France. Italy. Russia. Turkey. Spain and Portugal Minor States of Europe: Switzerland. Greece. Belgium. Holland. Denmark. Norway. Sweden. Bulgaria. Servia. Roumania. Montenegro. Luxemburg. Monaco. San Marino VII--AMERICA America Before Columbus The Primitive Races of America. The Ancient Civilisation of Central America. The Ancient Civilisation of South America The European Colonisation The Discovery. The Spanish Conquest. The Spanish and Portuguese Empire in America. The Independence of South and Central America. The Pilgrim Fathers and the English Settlement. The Development and Expansion of the British Colonies The American Nation The Revolt of the Thirteen Colonies. The Struggle for Independence and the War. The Creation of the United States. The Development of the American Nation. The United States in Our Own Time British America Canada. Newfoundland. British West Indies. British Honduras. Bermudas. Central America in the 19th and 20th Centuries Cuba. Haiti. Dominica. Porto Rico. Mexico. Guatemala. Honduras. San Salvador. Nicaragua. Costa Rica. Panama South America in the 19th and 20th Centuries Colombia. Venezuela. British, French and Dutch Guiana. Brazil. Ecuador. Peru. Chili. Bolivia. Paraguay. Argentina. Uruguay The World Around the Poles Greenland. Iceland. Arctic and Antarctic Oceans [Illustration: THE BOOK OF HISTORY] FIRST GRAND DIVISION MAN AND THE UNIVERSE] FIRST GRAND DIVISION MAN AND THE UNIVERSE There can, of course, be neither absolute finality nor entire unanimity in the subjects of these chapters, which are designed to enable the reader to follow the course of history with greater interest and understanding than would be possible without some scientific knowledge of life. They are presented as a symposium of modern thought on the problems concerning the origin and development of the earth and mankind PLAN THE WORLD AND ITS STORY A VIEW ACROSS THE AGES Rt. Hon. James Bryce A SUMMARY OF THE HISTORY OF THE WORLD Arthur D. Innes, M.A. CHRONOLOGY OF 10,000 YEARS AND CHART OF NATIONS MAKING OF THE EARTH & THE COMING OF MAN THE BEGINNING OF THE EARTH Dr. Wm. Johnson Sollas, F.R.S. HOW LIFE BECAME POSSIBLE ON THE EARTH Dr. Alfred Russel Wallace, F.R.S. HOW MAN OBTAINED THE MASTERY OF THE EARTH Dr. Archdall Reid, F.R.S.E. THE RISE OF MAN AND THE EVE OF HISTORY THE WORLD BEFORE HISTORY Professor Johannes Ranke THE GREAT STEPS IN MAN’S DEVELOPMENT Professor Joseph Kohler BIRTH OF CIVILISATION & THE GROWTH OF RACES THE BIRTH OF CIVILISATION Dr. Flinders Petrie, F.R.S. HOW CIVILISATION CAME TO EUROPE David George Hogarth, M.A. THE TRIUMPH OF RACE Dr. Archdall Reid, F.R.S.E. ALPHABET OF THE WORLD’S RACES W. E. Garrett Fisher, M.A. MAKING OF NATIONS & THE INFLUENCE OF NATURE Professor Friedrich Ratzel THE BIRTH AND GROWTH OF NATIONS INFLUENCE OF LAND & WATER ON NATIONAL HISTORY EFFECT OF ENVIRONMENT ON NATIONS THE SIZE AND POWER OF NATIONS THE FUTURE HISTORY OF MAN For full contents and page numbers see Index Mr. Kipling’s “Recessional” is quoted in a Frontispiece from “The Five Nations,” by permission of the Author and the Publishers, Messrs. Methuen [Illustration: THE WORLD AND ITS STORY] A VIEW ACROSS THE AGES AN INTRODUCTION TO THE BOOK OF HISTORY BY THE RIGHT HON. VISCOUNT BRYCE When History, properly so called, has emerged from those tales of the feats of kings and heroes and those brief entries in the roll of a temple or a monastery in which we find the earliest records of the past, the idea of composing a narrative which shall not be confined to the fortunes of one nation soon presents itself. [Sidenote: The First True Historian] Herodotus--the first true historian, and a historian in his own line never yet surpassed--took for his subject the strife between Greeks and Barbarians which culminated in the Great Persian War of B.C. 480, and worked into his book all he could ascertain regarding most of the great peoples of the world--Babylonians and Egyptians, Persians and Scythians, as well as Greeks. Since his time many have essayed to write a Universal History; and as knowledge grew, so the compass of these treatises increased, till the outlying nations of the East were added to those of the Mediterranean and West European world which had formerly filled the whole canvas. [Sidenote: Scientific History only now Possible] None of these books, however, covered the field or presented an adequate view of the annals of mankind as a whole. It was indeed impossible to do this, because the data were insufficient. Till some time way down in the nineteenth century that part of ancient history which was preserved in written documents could be based upon the literature of Israel, upon such notices regarding Egypt, Assyria, Babylon, and Iran as had been preserved by Greek or Roman writers, and upon those writers themselves. It was only for some of the Greek cities, for the kingdoms of Alexander and his successors, and for the city and Empire of Rome that fairly abundant materials were then available. Of the world outside Europe and Western Asia, whether ancient or modern, scarcely anything was known, scarcely anything even of the earlier annals of comparatively civilised peoples, such as those of India, China, and Japan, and still less of the rudimentary civilisations of Mexico and Peru. Nor, indeed, had most of the students who occupied themselves with the subject perceived how important a part in the general progress of mankind the more backward races have played, or how essential to a true History of the World is an account of the semi-civilised and even of the barbarous peoples. Thus it was not possible, until quite recent times, that the great enterprise of preparing such a history should be attempted on a plan or with materials suitable to its magnitude. The last seventy or eighty years have seen a vast increase in our materials, with a corresponding widening of the conception of what a History of the World should be. Accordingly, the time for trying to produce one upon a new plan and enlarged scale seems to have arrived; not, indeed, that the years to come will not continue to add to the historian’s resources, but that those resources have recently become so much ampler than they have ever been before that the moment may be deemed auspicious for a new departure. The nineteenth century was marked by three changes of the utmost consequence for the writing of history. [Illustration: THE WORLD AS KNOWN TO ITS FIRST HISTORIAN The world as known to Herodotus is shown by the white part of this map, indicating the limited range of ancient geographical knowledge. ] [Sidenote: New Material and New Methods] That century, in the first place, has enormously widened our knowledge of the times hitherto called prehistoric. The discovery of methods for deciphering the inscriptions found in Egypt and Western Asia, the excavations in Assyria and Egypt, in Continental Greece and in Crete, and to a lesser extent in North Africa also, in the course of which many inscriptions have been collected and fragments of ancient art examined, have given us a mass of knowledge regarding the nations who dwelt in these countries larger and more exact than was possessed by the writers of classical antiquity who lived comparatively near to those remote times. We possess materials for the study not only of the political history but of the ethnology, the languages, and the culture of the nations which were first civilised incomparably better than were those at the disposal of the contemporaries of Vico or Gibbon or Herder. Similar results have followed as regards the Far East, from the opening up of Sanskrit literature and of the records of China and Japan. To a lesser degree, the same thing has happened as regards the semi-civilised peoples of tropical America both north and south of the Isthmus of Panama. And while long periods of time have thus been brought within the range of history, we have also learnt much more about the times that may still be called prehistoric. The investigations carried on in mounds and caves and tombs and lake-dwellings, the collection of early stone and bronze implements, and of human skulls and bones found along with those of other animals, have thrown a great deal of new light upon primitive man, his way of life, and his migrations from one region to another. As history proper has been carried back many centuries beyond its former limit, so has our knowledge of prehistoric times been extended centuries above the furthest point to which history can now reach back. And this applies not only to the countries previously little explored, but to such well-known districts as Western Europe and the Atlantic coast of America. Secondly, there has been during the nineteenth century a notable improvement in the critical method of handling historical materials. Much more pains have been taken to examine all available documents and records, to obtain a perfect text of each by a comparison of manuscripts or of early printed copies, and to study each by the aid of other contemporary matter. It is true that, with the exception of Egyptian papyri and some manuscripts unearthed in Oriental monasteries (besides those Indian, Chinese, and other early Eastern sacred books to which I have already referred), not very much that is absolutely new has been brought to light. It is also true that a few of the most capable students in earlier days, in the ancient world as well as since the Renaissance, have fully seen the value of original authorities and have applied to them thoroughly critical methods. This is not a discovery of our own times. Still, it may be claimed that there was never before so great a zeal for collecting and investigating all possible kinds of original texts, nor so widely diffused a knowledge of the methods to be applied in turning them to account for the purposes of history. Both in Europe and in America an unprecedentedly large number of competent men have been employed upon researches of this kind, and the result of their labours on special topics has been to provide the writer who seeks to present a general view of history with materials not only larger but far fitter for his use than his predecessors ever enjoyed. Then with the improvement in critical apparatus, there has come a more cautious and exact habit of mind in the interpretation of facts. [Illustration: “THE FATHER OF HISTORY” Herodotus, the first historian, was born between B.C. 470-480 at Halicarnassus, a Greek colony in Asia Minor ] Thirdly, the progress of the sciences of Nature has powerfully influenced history, both by providing new data and by affecting the mental attitude of all reflective men. This has happened in several ways. Geographical exploration has made known nearly every part of the surface of the habitable globe. The great natural features of every country, its mountain ranges and rivers, its forest or deserts, have been ascertained. Its flora and fauna have been described, and thereby its capacity for supporting human life approximately calculated. The other physical conditions which govern the development of man, such as temperature, rainfall, and the direction of prevalent winds have been examined. Thus we have acquired a treasury of facts relating to the causes and conditions which help the growth of civilisation and mould it into diverse forms, conditions whose importance I shall presently discuss in considering the relation of man to his natural environment. Although a few penetrating minds had long ago seen how much the career of each nation must have been affected by physical phenomena, it is only in the last two generations that men have begun to study these phenomena in their relation to history, and to appreciate their influence in the formation of national types and in determining the movement of races over the earth’s surface. Not less remarkable has been the increase in our knowledge of the more remote and backward peoples. Nearly every one of these has now been visited by scientific travellers or missionaries, its language written down, its customs and religious rites, sometimes its folk lore also, recorded. Thus materials of the highest value have been secured, not only for completing our knowledge of mankind as a whole, but for comprehending in the early history of the now highly civilised peoples various facts which had previously remained obscure, but which became intelligible when compared with similar facts that can be studied in their actuality among tribes whom we find in the same stage to-day as were the ancestors of the civilised nations many centuries ago. [Sidenote: Progress of the Sciences] The progress thus achieved in the science of man regarded as a part of Nature has powerfully contributed to influence the study of human communities as they appear in history. The comparative method has become the basis for a truly scientific inquiry into the development of institutions, and the connection of religious beliefs and ceremonies with the first beginnings of institutions both social and political has been made clear by an accumulation of instances. Whether or no there be such a thing as a Science of History--a question which, since it is mainly verbal, one need not stop to discuss--there is such a thing as a scientific method applied to history; and the more familiar men have become with the methods of inquiry and canons of evidence used in physical investigations, so much the more have they tended to become exact and critical in historical investigations, and to examine the causes and the stages by and through which historical development is effected. [Sidenote: Historical Knowledge in Our Time] In noting this I do not suggest that what is popularly called the “Doctrine of Evolution” should be deemed a thing borrowed by history from the sciences of nature. Most of what is true or helpful in that doctrine was known long ago, and applied long ago by historical and political thinkers. You can find it in Aristotle, perhaps before Aristotle. Even as regards the biological sciences, the notion of what we call evolution is ancient; and the merit of Darwin and other great modern naturalists has lain, not in enouncing the idea as a general theory, but in elucidating, illustrating, and demonstrating the processes by which evolution takes place. The influence of the natural sciences on history is rather to be traced in the efforts we now see to accumulate a vast mass of facts relating to the social, economic, and political life of man, for the sake of discovering general laws running through them, and imparting to them order and unity. Although the most philosophic and diligent historians have always aimed at and striven for this, still the general diffusion of the method in our own time, and the greatly increased scale on which it is applied, together with the higher standard of accuracy which is exacted by the opinion of competent judges, may be, in some measure, ascribed to the examples which those who work in the spheres of physics and biology and natural history have so effectively set. Finally, the progress of natural science has in our time, by stimulating the production and exchange of commodities, drawn the different parts of the earth much nearer to one another, and thus brought nearly all its tribes and nations into relations with one another far closer and far more frequent than existed before. [Sidenote: Oneness of the Human Race] This has been done by the inventions that have given us steam and electricity as motive forces, making transport quicker and cheaper, and by the application of electricity to the transmission of words. No changes that have occurred in the past (except perhaps changes in the sphere of religion) are comparable in their importance as factors in history to those which have shortened the voyage from Western Europe to America to five and a half days, and made communication with Australia instantaneous. For the first time the human race, always essentially one, has begun to feel itself one, and civilised man has in every part of it become a contemporaneous observer of what passes in every other part. The general result of these various changes has been that while the materials for writing a history of the world have been increased, the conception of what such a history should be has been at the same time both enlarged and defined. Its scope is wider; its lines are more clearly drawn. But what do we mean by a Universal History? Briefly, a History which shall, first, include all the races and tribes of man within its scope; and, secondly, shall bring all these races and tribes into a connection with one another such as to display their annals as an organic whole. [Sidenote: Importance of the Small Races] Universal history has to deal not only with the great nations, but also with the small nations; not only with the civilised, but also with the barbarous or savage peoples; not only with the times of movement and progress, but also with the times of silence and apparent stagnation. Every fraction of humanity has contributed something to the common stock, and has lived and laboured not for itself only, but for others also, through the influence which it has perforce exercised on its neighbours. The only exceptions we can imagine are the inhabitants of some remote isle, “far placed amid the melancholy main.” Yet they, too, must have once formed part of a race dwelling in the region whence they came, even if that race had died out in its old home before civilised man set foot on such an oceanic isle in a later age. The world would have been different, in however small a measure, had they never existed. As in the realm of physical science, so in that of history no fact is devoid of significance, though the true significance may remain long unnoticed. The history of the backward races presents exceptional difficulties, because they have no written records, and often scarcely any oral traditions. Sometimes it reduces itself to a description of their usages and state of life, their arts and their superstitions, at the time when civilised observers first visited them. Yet that history is instructive, not only because the phenomena observable among such races enlarge our knowledge, but also because through the study of those which survive we are able to interpret the scanty records we possess of the early condition of peoples now civilised, and to go some way towards writing the history of what we have hitherto called prehistoric man. [Illustration: ANCIENT EGYPT’S STRANGE BOOKS AND PICTORIAL RECORDS, MADE OF PAPYRUS Papyrus, a tall, graceful, sedgy plant, supplied the favourite writing material of the ancient world, and many priceless records of antiquity are preserved to us in papyri. The pith of the plant was pressed flat and thin and joined with others to form strips, on which records were written or painted. The above is a photograph of a piece of Egyptian papyrus, showing both hieroglyphics and picture-writing. The oldest piece of papyrus dates back to B.C. 3500. ] Thus such tribes as the aborigines of Australia, the Fuegians of Magellan’s Straits, the Bushmen of South Africa, the Sakalavas of Madagascar, the Lapps of Northern Europe, the Ainos of Japan, the numerous “hill-tribes” of India, will all come within the historian’s ken. From each of them something may be learnt; and each of them has through contact with its more advanced neighbours affected those neighbours themselves, sometimes in blood, sometimes through superstitious beliefs or rites, frequently borrowed by the higher races from the lower (as the Norsemen learnt magic from the Lapps, and the Semites of Assyria from the Accadians), sometimes through the strife which has arisen between the savage and the more civilised man, whereby the institutions of the latter have been modified. Obviously the historian cannot record everything. These lower races are comparatively unimportant. Their contributions to progress, their effect on the general march of events, have been but small. But they must not be wholly omitted from the picture, for without them it would have been different. One must never forget, in following the history of the great nations of antiquity, that they fought and thought and built up the fabric of their industry and art in the midst of a barbarous or savage population surrounding them on all sides, whence they drew the bulk of their slaves and some of their mercenary soldiers, and which sometimes avenged itself by sudden inroads, the fear of which kept the Greek cities, and at certain epochs even the power of Rome, watchful and anxious. So in modern times the savages among whom European colonies have been planted, or who have been transported as slaves to other colonies--sometimes, as in the case of Portugal in the fifteenth century, to Europe itself--or those with whom Europeans have carried on trade, must not be omitted from a view of the causes which have determined the course of events in the civilised peoples. [Sidenote: Great Works of Little Peoples] To dwell on the part played by the small nations is less necessary here, for even a superficial student must be struck by the fact that some of them have counted for more than the larger nations to whose annals a larger space is commonly allotted. The instance of Israel is enough, so far as the ancient world is concerned, to show how little the numbers of a people have to do with the influence it may exert. For the modern world, I will take the case of Iceland. [Sidenote: The Culture of the Icelanders] The Icelanders are a people much smaller than even was Israel. They have never numbered more than about seventy thousand. They live in an isle so far remote, and so sundered from the rest of the world by an inhospitable ocean, that their relations both with Europe, to which ethnologically they belong, and with America, to which geographically they belong, have been comparatively scanty. But their history, from the first settlement of the island by Norwegian exiles in A.D. 874 to the extinction of the National Republic in A.D. 1264, is full of interest and instruction, in some respects a perfectly unique history. And the literature which this handful of people produced is certainly the most striking primitive literature which any modern people has produced, superior in literary quality to that of the Continental Teutons, or to that of the Romance nations, or to that of the Finns or Slavs, or even to that of the Celts. Yet most histories of Europe pass by Iceland altogether, and few persons in Continental Europe (outside Scandinavia) know anything about the inhabitants of this isle, who, amid glaciers and volcanoes, have maintained themselves at a high level of intelligence and culture for more than a thousand years. The small peoples have no doubt been more potent in the spheres of intellect and emotion than in those of war, politics, or commerce. But the influences which belong to the sphere of creative intelligence--that is to say, of literature, philosophy, religion and art--are just those which it is peculiarly the function of a History of the World to disengage and follow out in their far-reaching consequence. They pass beyond the limits of the country where they arose. They survive, it may be, the race that gave birth to them. They pass into new forms, and through these they work in new ways upon subsequent ages. [Sidenote: The Wide Scope of History] It is also the task of universal history so to trace the march of humanity as to display the relation which each part of it bears to the others; to fit each race and tribe and nation into the main narrative. To do this, three things are needed--a comprehensive knowledge, a power of selecting the salient and significant points, and a talent for arrangement. Of these three qualifications, the first is the least rare. Ours is an age of specialists; but the more a man buries himself in special studies, the more risk does he incur of losing his sense of the place which the object of his own study fills in the general scheme of things. The highly trained historian is generally able to draw from those who have worked in particular departments the data he needs; while the master of one single department may be unable to carry his vision over the whole horizon, and see each part of the landscape in its relations to the rest. In other words, a History of the World ought to be an account of the human family as an organic whole, showing how each race and state has affected other races or states, what each has brought into the common stock, and how the interaction among them has stimulated some, depressed or extinguished others, turned the main current this way or that. Even when the annals of one particular country are concerned, it needs no small measure of skill in expression as well as of constructive art to trace their connection with those of other countries. To take a familiar example, he who writes the history of England must have his eye always alive to what is passing in France on one side, and in Scotland on the other, not to speak of countries less closely connected with England, such as Germany and Spain. He must let the reader feel in what way the events that were happening in France and Scotland affected men’s minds, and through men’s minds affected the progress of events in England. Yet he cannot allow himself constantly to interrupt his English narrative in order to tell what was passing beyond the Channel or across the Tweed. [Illustration: VIVID SCENES OF ANCIENT LIFE DEPICTED BY CONTEMPORARY ARTISTS The walls of the tombs in Egypt form a great picture gallery of the vanished life of that country and are invaluable to the historian. This fragment from the British Museum shows how vividly the domestic figures were realised. ] [Sidenote: Unity of Universal History] Obviously, this difficulty is much increased when the canvas is widened to include all Europe, and when the aim is to give the reader a just impression of the general tendencies of a whole age, such an age as, for instance, the sixteenth century, over that vast area. If for a History of the World the old plan be adopted--that of telling the story of each nation separately, yet on lines generally similar, cross references and a copious use of chronological tables become helpful, for they enable the contemporaneity of events to be seen at a glance, and as the history of each nation is being written with a view to that of other nations, the tendencies at work in each can be explained and illustrated in a way which shows their parallelism, and gives to the whole that unity of meaning and tendency which a universal history must constantly endeavour to display. The connection between the progress or decline of different peoples is best understood by setting forth the various forms which similar tendencies take in each. To do this is a hard task when the historian is dealing with the ancient world, or with the world outside Europe even in mediæval and post-mediæval times. For the modern European nations it is easier, because, ever since the spread of Christianity made these nations parts of one great ecclesiastical community, similar forces have been at work upon each of them, and every intellectual movement which has told upon one has more or less told upon the others also. [Illustration: THE MASTER-KEY TO THE HIEROGLYPHICS The inscribed stone found at Rosetta, in the Nile delta, in 1799, now preserved in the British Museum. It gave the key to the hieroglyphic writings of Egypt. It is a decree of Ptolemy Epiphanes, promulgated at Memphis in B.C. 196, and as it is inscribed in hieroglyphic and in the script of the country as well as in Greek, it thus solved the long standing mystery of the hieroglyphics of the monuments, which before its discovery had been quite unintelligible. ] [Sidenote: Central Line of Human Development] [Sidenote: The Study of Human Society] [Sidenote: Each Race a Distinct Entity] Such a History of the World may be written on more than one plan, and in the light of more than one general theory of human progress. It might find the central line of human development in the increase of man’s knowledge, and in particular of his knowledge of Nature and his power of dealing with her. Or that which we call culture, the comprehensive unfolding and polishing of human faculty and of the power of intellectual creation and appreciation, might be taken as marking the most real and solid kind of progress, so that its growth would best represent the advance of man from a savage to a highly civilised condition. Or if the moral and political sphere were selected as that in which the onward march of man as a social being, made to live in a community, could best be studied, the idea of liberty might be made a pivot of the scheme; for in showing how the individual emerges from the family or the tribe, how first domestic and then also prædial slavery slowly disappears, how institutions are framed under which the will of one ruler or of a small group begins to be controlled, or replaced as a governing force, by the collective will of the members of the community, how the primordial rights of each human creature win their way to recognition--in tracing out all these things the history of human society is practically written, and the significance of all political changes is made clear. Another way, again, would be to take some concrete department of human activity, follow it down from its earliest to its latest stages, and group other departments round it. Thus one author might take religion, and in making the history of religion the main thread of his narrative might deal incidentally with the other phenomena which have influenced it or which it has influenced. Or, similarly, another author might take political institutions, or perhaps economic conditions--_i.e._, wealth, labour, capital, commerce, or, again, the fundamental social institutions, such as the family, and the relations of the ranks and classes in a community, and build up round one or other of these manifestations and embodiments of the creative energy of mankind the general story of man’s movement from barbarism to civilisation. Even art, even mechanical inventions, might be similarly handled, for both of these stand in a significant relation to all the rest of the life of each nation and of the world at large. Nevertheless, no one of these suggested lines on which a universal history might be constructed would quite meet the expectations which the name Universal History raises, because we have become accustomed to think of history as being primarily and pre-eminently a narrative of the growth and development of communities, nations, and states as organised political bodies, seeing that it is in their character as bodies so organised that they come into relation with other nations and states. It is therefore better to follow the familiar plan of dealing with the annals of each race and nation as a distinct entity, while endeavouring to show throughout the whole narrative the part which each fills in the general drama of human effort, conflict, and progress. A universal history may, however, while conforming to this established method, follow it out along a special line, which shall give prominence to some one leading idea or principle. Such a line or point of view has been found for the present work in the relation of man to his physical environment--that is to say, to the geographical conditions which have always surrounded him, and always must surround him, conditions whose power and influence he has felt ever since he appeared upon the globe. This point of view is more comprehensive than any one of those above enumerated. Physical environment has told upon each and every one of the lines of human activity already enumerated that could be taken to form a central line for the writing of a history of mankind. It has influenced not only political institutions and economic phenomena, but also religion, and social institutions, and art, and inventions. No department of man’s life has been independent of it, for it works upon man not only materially but also intellectually and morally. [Illustration: UNEARTHING THE RUINS OF ANCIENT BABYLON IN THE TWENTIETH CENTURY This photograph illustrates how present-day exploration brings the remains of the ancient wonder cities of Babylonia to light after the sleep of ages. Much valuable knowledge of Babylon has been acquired quite recently as a result of excavations now being carried on under the supervision of English, American, French, and German explorers. ] As this is the idea which has governed the preparation of the present book, as it is constructed upon a geographical rather than a purely chronological plan (though, of course, each particular country and nation needs to be treated chronologically), some few pages may properly be devoted here to a consideration of the way in which geography determines history, or, in other words, to an examination of the relations of Nature, inorganic and organic, to the life of man. MAN’S PLACE IN NATURE’S KINGDOM Though we are accustomed to contrast man with Nature, and to look upon the world outside ourselves as an object to be studied by man, the conscious and intelligent subject, it is evident, and has been always recognised even by those thinkers who have most exalted the place man holds in the Cosmos, that man is also to be studied as a part of the physical universe. He belongs to the realm of Nature in respect of his bodily constitution, which links him with other animals, and in certain respects with all the phenomena that lie within the sphere of biology. All creatures on our earth, since they have bodies formed from material constituents, are subject to the physical laws which govern matter; and the life of all is determined, so far as their bodies are concerned, by the physical conditions which foster, or depress, or destroy life. Plants need soil, moisture, sunshine, and certain constituents of the atmosphere. Their distribution over the earth’s surface depends not only upon the greater or less extent to which these things, essential to their existence, are present, but also upon the configuration of the earth’s surface (continents and oceans), upon the greater or less elevation above sea level of parts of it, upon such forces as winds and ocean currents (occasionally also upon volcanoes), upon the interposition of arid deserts between moister regions, or upon the flow of great rivers. The flora of each country is the resultant (until man appears upon the scene) of these natural conditions. [Sidenote: Natural Conditions of Life] We know that some plants are also affected by the presence of certain animals, particularly insects and birds. Similarly, animals depend upon these same conditions which regulate their distribution, partly directly, partly indirectly, or mediately through the dependence of the animal for food upon the plants whose presence or absence these conditions have determined. It would seem that animals, being capable of moving from place to place, and thus of finding conditions suitable for their life, and to some extent of modifying their life to suit the nature around them, are somewhat more independent than plants are, though plants, too, possess powers of adapting themselves to climatic surroundings; and there are some--such, for instance, as our common brake-fern and the grass of Parnassus--which seem able to thrive unmodified in very different parts of the globe. [Sidenote: Man the Servant of Nature] The primary needs of man which he shares with the other animals are an atmosphere which he can breathe, a temperature which he can support, water which he can drink, and food. In respect of these he is as much the product of geographical conditions as are the other living creatures. Presently he superadds another need, that of clothing. It is a sign that he is becoming less dependent on external conditions, for by means of clothing he can make his own temperature and succeed in enduring a degree of cold, or changes from heat to cold, which might otherwise shorten his life. The discovery of fire carries him a long step further, for it not only puts him less at the mercy of low temperatures, but extends the range of his food supplies, and enables him, by procuring better tools and weapons, to obtain his food more easily. We need not pursue his upward course, at every stage of which he finds himself better and still better able to escape from the thraldom of Nature, and to turn to account the forces which she puts at his disposal. But although he becomes more and more independent, more and more master not only of himself, but of her, he is none the less always for many purposes the creature of the conditions with which she surrounds him. He always needs what she gives him. He must always have regard to the laws which he finds operating through her realm. He always finds it the easiest course to obey, and to use rather than to attempt to resist her. Here let me pause to notice a remarkable contrast between the earlier and the later stages of man’s relations to Nature. In the earlier stages he lies helpless before her, and must take what she chooses to bestow--food, shelter, materials for clothing, means of defence against the wild beasts, who are in strength far more than a match for him. He depends upon her from necessity, and is better or worse off according as she is more or less generous. [Sidenote: Man’s Advance in Knowledge] But in the later stages of his progress he has, by accumulating a store of knowledge, and by the development of his intelligence, energy, and self-confidence, raised himself out of his old difficulties. He no longer dreads the wild beasts. They, or such of them as remain, begin to dread him, for he is crafty, and can kill them at a distance. He erects dwellings which can withstand rain and tempest. He irrigates hitherto barren lands and raises abundant crops from them. When he has invented machinery, he produces in an hour clothing better than his hands could formerly have produced in a week. If at any given time he has not plenty of food, this happens only because he has allowed his species to multiply too fast. He is able to cross the sea against adverse winds and place himself in a more fertile soil or under more genial skies than those of his former home. As respects all the primary needs of his life, he has so subjected Nature to himself, that he can make his life what he will. Neurdein THE FIRST WANDERERS OF THE EARTH: TRIBAL MIGRATION IN PREHISTORIC TIMES From the painting of “Cain” by Ferdinand Cormon ] [Sidenote: Man the Master of Nature] All this renders him independent. But he now also finds himself drawn into a new kind of dependence, for he has now come to take a new view of Nature. He perceives in her an enormous storehouse of wealth, by using which he can multiply his resources and gratify his always increasing desires to an extent practically unlimited. She provides forces, such as steam and electricity, which his knowledge enables him to employ for production and transport, so as to spare his own physical strength, needed now not so much for effort as for the direction of the efforts of Nature. She has in the forest, and still more beneath her own surface in the form of minerals, the materials by which these forces can be set in motion; and by using these forces man can, with comparatively little trouble, procure abundance of those materials. Thus his relation to Nature is changed. It was that of a servant, or, indeed, rather of a beggar, needing the bounty of a sovereign. It is now that of a master needing the labour of a servant, a servant infinitely stronger than the master, but absolutely obedient to the master so long as the master uses the proper spell. Thus the connection of man with Nature, changed though his attitude be, is really as close as ever, and far more complex. If his needs had remained what they were in his primitive days--let us say, in those palæolithic days which we can faintly adumbrate to ourselves by an observation of the Australian or Fuegian aborigines now--he would have sat comparatively lightly to Nature, getting easily what he wanted, and not caring to trouble her for more. But his needs--that is to say, his desires, both his physical appetites and his intellectual tastes, his ambitions and his fondness for comfort, things that were once luxuries having become necessaries--have so immeasurably expanded that, since he asks much more from Nature, he is obliged to study her more closely than ever. [Sidenote: Man’s New Relations to Nature] Thus he enters into a new sort of dependence upon her, because it is only by understanding her capacities and the means of using them that he can get from her what he wants. Primitive man was satisfied if he could find spots where the trees gave edible fruit, where the sun was not too hot, nor the winds too cold, where the beasts easy of capture were abundant, and no tigers or pythons made the forest terrible. Civilised man has more complex problems to deal with, and wider fields to search. The study of Nature is not only still essential to him, but really more essential than ever. His life and action are conditioned by her. His industry and his commerce are directed by her to certain spots. That which she has to give is still, directly or indirectly, the source of strife, and a frequent cause of war. As men fought long ago with flint-headed arrows for a spring of water or a coconut grove, so they fight to-day for mineral treasures imbedded in the soil. It is mainly by Nature that the movements of emigration and the rise of populous centres of industry are determined. Though Nature still rules for many purposes and in many ways the course of human affairs, the respective value of her various gifts changes from age to age, as man’s knowledge and power of turning them to account have changed. The things most prized by primitive man are not those which semi-civilised man chiefly prized, still less are they those most sought for now. [Sidenote: Using Natural Wealth] In primitive times the spots most attractive, because most favourable to human life, were those in which food could be most easily and safely obtained from fruit-bearing trees or by the chase, and where the climate was genial enough to make clothing and shelter needless, at least during the greater part of the year. Later, when the keeping of cattle and tillage had come into use, good pastures and a fertile soil in the valley of a river were the chief sources of material well-being. Wild beasts were less terrible, because man was better armed; but as human enemies were formidable, regions where hills and rocks facilitated defence by furnishing natural strongholds had their advantages. Still later, forests came to be recognised as useful for fuel, and for carpentry and shipbuilding. Mineral deposits, usually found in hilly or mountainous districts, became pre-eminently important sources of wealth; and rivers were valued as highways of commerce and as sources of motive power by the force of their currents. To the Red Indians of the Ohio valley the places which were the most attractive camping-grounds were those whither the buffaloes came in vast herds to lick the rock salt exposed in the sides of the hills. It is now not the salt-licks, but the existence of immense deposits of coal and iron, that have determined the growth of huge communities in those regions whence the red man and the buffalo have both vanished. England was once, as New Zealand is now, a great wool-growing and wool-exporting country, whereas she is to-day a country which spins and weaves far more wool than she produces. [Sidenote: Ancient Harbours and Modern] So, too, the influence of the sea on man has changed. There was a time when towns were built upon heights some way off from the coast, because the sea was the broad high road of pirates who swooped down upon and pillaged the dwellings of those who lived near it. Now that the sea is safe, trading cities spring up upon its margin, and sandy tracts worthless for agriculture have gained an unexpected value as health resorts, or as places for playing games, places to which the inhabitants of inland districts flock in summer, as they do in England and Germany, or in winter, as they do on the Mediterranean coasts of France. The Greeks, when they began to compete with the Phœnicians in maritime commerce, sought for small and sheltered inlets in which their tiny vessels could lie safely--such inlets as Homer describes in the Odyssey, or as the Old Port of Marseilles, a city originally a colony from the Ionian Phocæa. Nowadays these pretty little rock harbours are useless for the large ships which carry our trade. The Old Port of Marseilles is abandoned to small coasters and fishing-boats, and the ocean steamers lie in a new harbour which is protected, partly by outlying islands, partly by artificial works. [Sidenote: The World-Importance of Medicine] So, too, river valleys, though still important as highways of traffic, are important not so much in respect of water carriage as because they furnish the easiest lines along which railways can be constructed. The two banks of the Rhine, each traversed by a railroad, carry far more traffic than the great stream itself carried a century ago; and the same remark applies to the Hudson. All these changes are due to the progress of invention, which may give us fresh changes in the future not less far-reaching than those the past has seen. Mountainous regions with a heavy rainfall, such as Western Norway or the coast of the Pacific in Washington and British Columbia, may, by the abundance of water power which they supply, which can be transmuted into electrical energy, become sources of previously unlooked-for wealth, especially if some cheap means can be devised of conveying electricity with less wastage in transmission than is at present incurred. Within the last few years considerable progress in this direction has been made. Should effective and easily applicable preventives against malarial fever be discovered, many districts now shunned, because dangerous to the life of white men, may become the homes of flourishing communities. The discovery of cinchona bark in the seventeenth century affected the course of events, because it provided a remedy against a disease that had previously baffled medical skill. If quinine had been at the disposal of the men of the Middle Ages, not only might the lives of many great men, as for instance of Dante, have been prolonged, but the Teutonic emperors would have been partially relieved of one of the chief obstacles which prevented them from establishing permanent control over their Italian dominions. Rome and the Papal power defended themselves against the hosts of the Franconian and Hohenstaufen sovereigns by the fevers of the Campagna more effectively than did the Roman people by their arms, and almost as effectively as did the Popes by their spiritual agencies. Bearing in mind this principle, that the gifts of Nature to man not only increase, but also vary in their form, in proportion and correspondence to man’s capacity to use them, and remembering also that man is almost as much influenced by Nature when he has become her adroit master as when she was his stern mistress, we may now go on to examine more in detail the modes in which her influence has told and still tells upon him. [Sidenote: The Problem of Racial Distinctions] It has long been recognised that Nature must have been the principal factor in producing, that is to say, in differentiating, the various races of mankind as we find them differentiated when our records begin. How this happened is one of the darkest problems that history presents. By what steps and through what causes did the races of man acquire these diversities of physical and intellectual character which are now so marked and seem so persistent? It has been suggested that some of these diversities may date back to a time when man, as what is called a distinct species, had scarcely begun to exist. Assuming the Darwinian hypothesis of the development of man out of some pithecoid form to be correct--and those who are not themselves scientific naturalists can of course do no more than provisionally accept the conclusions at which the vast majority of scientific naturalists have arrived--it is conceivable that there may have been unconnected developments of creatures from intermediate forms into definitely human forms in different regions, and that some of the most marked types of humanity may therefore have had their first rudimentary and germinal beginning before any specifically human type had made its appearance. This, however, is not the view of the great majority of naturalists. They appear to hold that the passage either from some anthropoid apes, or from some long since extinct common ancestor of man and the existing anthropoid apes--this latter alternative representing what is now the dominant view--did not take place through several channels (so to speak), but through one only, and that there was a single specifically human type which subsequently diverged into the varieties we now see. [Illustration: TREE DWELLERS IN THE TWENTIETH CENTURY We must remember that such terms as “The Stone Age,” “The Bronze Age,” and so forth, are only loosely applied. The ages so called did not close at certain periods. There are races now living in all the conditions of these past ages. This photograph, for example, shows the actual tree dwellings of the Papuans in New Guinea to-day--one of the most primitive forms of human habitation. ] If this be so, it is plain that climate, and the conditions of life which depend upon climate, soil, and the presence of vegetables and of other animals besides man, must have been the forces which moulded and developed those varieties. From a remote antiquity, everybody has connected the dark colour of all, or nearly all, the races inhabiting the torrid zone with the power of the sun; and the fairer skin of the races of the temperate and arctic zones with the comparative feebleness of his rays in those regions. This may be explained on Darwinian principles by supposing that the darker varieties were found more capable of supporting the fierce heat of the tropics. What explanation is to be given of the other characteristics of the negro and negroid races, of the usually frizzled hair, of the peculiar nose and jaw, and so forth, is a question for the naturalist rather than for the historian. Although climate and food may be the chief factors in differentiation, the nature of the process is, as indeed is the case with the species of animals generally, sometimes very obscure. Take an instance from three African races which, so far as we can tell, were formed under similar climatic conditions--the Bushmen, the Hottentots, and the Bantu, the race including those whom we call Kaffirs. Their physical aspect and colour are different. Their size and the structure of their bodies are different. Their mental aptitudes are different; and one of the oddest points of difference is this, that whereas the Bushmen are the least advanced, intellectually, morally, and politically, of the three races, as well as the physically weakest, they show a talent for drawing which is not possessed by the other two. [Illustration: THE HABITATIONS OF MAN IN ALL AGES OF THE WORLD’S HISTORY At first man built twig huts in trees, but becoming better matched with his animal foes he took to caves and underground habitations. Our illustration of the latter shows a section through the soil. Lake dwellings marked a distinct advance. Other varieties of primitive habitations are the leaf hut, the tents of skin, the mud hut, and the beehive hut of stone. Roman villas are still models of beauty. American “skyscrapers” are peculiar to our time; but all early forms of dwellings, while marking progress, have existed contemporaneously throughout history. ] [Sidenote: Is the Race Mystery Insoluble?] In this case there is, of course, a vast unknown fore-time during which we may imagine the Bantu race, probably originally formed in a region other than that which it now occupies (and under more favourable conditions for progress), to have become widely differentiated from those which are now the lower African races. We still know comparatively little about African ethnography. Let us, therefore, take another instance in which affinities of language give ground for believing that three races, whose differences are now marked, have diverged from a common stock. So far as language goes, the Celts, the Teutons, and the Slavs, all speaking Indo-European tongues, may be deemed to be all nearly connected in origin. They are marked by certain slight physical dissimilarities, and by perhaps rather more palpable dissimilarities in their respective intellectual and emotional characters. But so far as our knowledge goes, all three have lived for an immensely long period in the colder parts of the temperate zone, under similar external conditions, and following very much the same kind of pastoral and agricultural life. There is nothing in their environment which explains the divergences we perceive; so the origin of these divergences must apparently be sought either in admixture with other races or in some other historical causes which are, and will for ever remain, in the darkness of a recordless past. [Sidenote: Mixing of the World’s Peoples] How race admixture works, and how it forms a new definite character out of diverse elements, is a subject which anyone may find abundant materials for studying in the history of the last two thousand years. Nearly every modern European people has been so formed. The French, the Spaniards, and the English are all the products of a mixture, in different proportions, of at least three elements--Iberian (to use a current name), Celts, and Teutons, though the Celtic element is probably comparatively small in Spain, and the Teutonic comparatively small both in Spain and in Central and Southern France. No small part of those who to-day speak German and deem themselves Germans must be of Slavonic stock. Those who to-day speak Russian are very largely of Finnish, to some small extent of Tartar, blood. The Italians probably spring from an even larger number of race-sources, without mentioning the vast number of slaves brought from the East and the North into Italy between B.C. 100 and A.D. 300. In the cases of Switzerland and Scotland the process of fusion is not yet complete. The Celto-Burgundian Swiss of Neuchatel is still different from the Allemanian Swiss of Appenzell; as the Anglo-Celt of Fife is different from the Ibero-Celt of the Outer Hebrides. But in both these cases there is already a strong sense of national unity, and in another three hundred years there may have arisen a single type of character. [Sidenote: The Unique Case of Iceland] An interesting and almost unique case is furnished by Iceland, where isolation under peculiar conditions of climate, food, and social life has created a somewhat different type both of body and of mental character from that of the Norwegians, although so far as blood goes the two peoples are identical, Iceland having been colonised from Western Norway a thousand years ago, and both Icelanders and Norwegians having remained practically unmixed with any other race--save that some slight Celtic infusion came to Iceland with those who migrated thither from the Norse settlements in Ireland, Northern Scotland, and the Hebrides--since the separation took place. But by far the most remarkable instance of race admixture is that furnished in our own time by the United States of North America, where a people of predominantly English stock (although there were in the end of the eighteenth century a few descendants of Dutchmen, with Germans, Swedes, and Ulster Irishmen, in the country) has within the last sixty years received additions of many millions of Celts, of Germans and Scandinavians, and of various Slavonic races. At least a century must elapse before it can be seen how far this infusion of new blood will change the type of American character as it stood in 1840. There are, however, two noteworthy differences between modern race fusions and those which belong to primitive times. One is that under modern conditions the influence of what may be called the social and political environment is probably very much greater than it was in early times. The American-born son of Irish parents is at forty years of age a very different creature from his cousin on the coast of Mayo. The other is that in modern times differences of colour retard or forbid the fusion of two races. So far as the Teutonic peoples are concerned, no one will intermarry with a negro; a very few with a Hindu, a Chinese, or a Malay. In the ancient world there was but little contact between white men and black or yellow ones, but the feeling of race aversion was apparently less strong than it is now, just as it was much less strong among the Spaniards and Portuguese in the sixteenth and seventeenth centuries than it is among Americans or Englishmen to-day. It is less strong even now among the so-called “Latin races;” and as regards the Anglo-Americans, it is much less strong towards the Red Indians than towards negroes. [Illustration: THE REMARKABLE INFLUENCE OF ENVIRONMENT ON PHYSICAL APPEARANCE Mr. Bryce points out that the physical features of a people are determined chiefly by their environment. These illustrations show (at top) a typical English settler in the old Colonial days of America, a native Red Indian (left) and a typical American of to-day (right). Without any intermingling of red men and white, the modern American, thanks to climatic conditions, resembles the Red Indian far more closely than he does his own ancestors of the Colonial days. ] As Nature must have been the main agent in the formation of the various races of mankind from a common stock, so also Nature has been the chief cause of their movements from one part of the earth to another, these movements having been in their turn a potent influence in the admixture of the races. Some geographers have alleged climate--that is to say, the desire of those who inhabit an inclement region to enjoy a softer and warmer air--as a principal motive which has induced tribes of nations to transfer themselves from one region to another. It is no doubt true that the direction of migrations has almost always been either from the north towards the south, or else along parallels of latitude, men rarely seeking for themselves conditions more severe than those under which they were born. But it is usually not so much the wish to escape cold that has been an effective motive as the wish to find more and better food, since this means an altogether easier life. Scarcity of the means of subsistence, which is, of course, most felt when population is increasing, has operated more frequently and powerfully than any other cause in bringing on displacements of the races of man over the globe. The movement of the primitive Aryans into India from the plateaux of West Central Asia, probably also the movement of the races which speak Dravidian languages from South Central Asia into Southern India, and probably also the mighty descent, in the fourth and fifth centuries A.D., of the Teutonic races from the lands between the Baltic and the Alps into the Roman Empire, had this origin. [Sidenote: The Colonising Impulse] In more advanced states of society a like cause leads the surplus population of a civilised state to overflow into new lands, where there is more space, or the soil is more fertile. Thus the inhabitants of Southwestern Scotland, partly, no doubt, at the suggestion of their rulers, crossed over into Ulster, where they occupied the best lands, driving the aboriginal Celts into the rougher and higher districts, where their descendants remain in the glens of Antrim, and in the hilly parts of Down, Derry, and Tyrone. Thus the men of New England moved out to the West and settled in the Mississippi Valley, while the men of Virginia crossed the Alleghanies into Kentucky. Thus the English have colonised Canada and Australia and New Zealand and Natal. Thus the Russians have spread out from their ancient homes on the upper courses of the Dnieper and the Volga all over the vast steppes that stretch to the Black Sea and the Caucasus, as well as into the rich lands of Southwestern Siberia. Thus the surplus peasantry of Germany has gone not only to North America, but also to Southern Brazil and the shores of the Rio de la Plata. [Sidenote: The Need of Native Labour] In another form it is the excess of population over means of subsistence at home that has produced the remarkable outflow of the Chinese through the Eastern Archipelago and across the Pacific into North America, and that has carried the Japanese to the Hawaiian Islands. And here we touch another cause of migration which is indirectly traceable to Nature--namely, the demand in some countries for more labour or cheaper labour than the inhabitants of the country are able or willing to supply. Sometimes this demand is attributable to climatic causes. The Spaniards and Portuguese and English in the New World were unfitted by their physical constitutions for out-of-door labour under a tropical sun. Hence they imported negroes during the sixteenth and two following centuries in such numbers that there are now about eight millions of coloured people in the United States alone, and possibly (though no accurate figures exist) as many more in the West Indies and South America. To a much smaller extent the same need for foreign labour has recently brought Indian coolies to the shores of the Caribbean Sea, and to the hottest parts of Natal, as it brings Polynesians to the sugar plantations of Northern Queensland. [Sidenote: What Determines Race Movements] Two other causes which have been potent in bringing about displacements and mixtures of population are the desire for conquest and plunder and the sentiment of religion. But these belong less to the sphere of Nature than to that of human passion and emotion, so that they scarcely fall within this part of our inquiry, the aim of which has been to show how Nature has determined history by inducing a shifting of races from place to place. From this shifting there has come the contact of diverse elements, with changes in each race due to the influence of the other, or perhaps the absorption of one in the other, or the development of something new out of both. In considering these race movements we have been led from the remote periods in which they began, and of which we know scarcely anything except from archæological and linguistic data, to periods within the range of authentic history. So we may go on to see how Nature has determined the spots in which the industry of the more advanced races should build up the earliest civilisations, and the lines along which commerce, a principal agent in the extension of civilisation, should proceed to link one race with another. [Illustration: THE MERCHANT MARINERS OF THE ANCIENT WORLD The earliest agents in the diffusion of trades and the arts were the Phœnicians, who from their great cities of Tyre, Sidon, and Carthage conducted a sea-borne traffic with lands as remote as England, and whose adventurous sailors, despite the smallness of their vessels, are believed even to have succeeded in rounding the Cape of Good Hope. ] [Sidenote: Isolation of Eastern Peoples] It was long since observed that the first homes of a dense population and a highly developed civilisation lay in fertile river valleys, such as those of the Lower Nile, the Euphrates, the Tigris, the Ganges, the Yang-tse-kiang. All these are situate in the hotter parts of the temperate zone; all are regions of exceptional fertility. The soil, especially when tillage has become general, is the first source of wealth; and it is in the midst of a prosperous agricultural population that cities spring up where handicrafts and the arts arise and flourish. The basins of the Lower Nile and of the Lower Euphrates and Tigris are (as respects the West Asiatic and Mediterranean world) the fountain-heads of material, military, and artistic civilisation. From them it spreads over the adjacent countries and along the coasts of Europe and Africa. On the east, Egypt and Mesopotamia are cut off by the deserts of Arabia and Eastern Persia from the perhaps equally ancient civilisation of India, which again is cut off by lofty and savage mountains from the very ancient civilisation of China. Nature forbade intercourse between these far eastern regions and the West Asian peoples, while on the other hand Nature permitted Egypt, Phœnicia, and Babylon to influence and become teachers of the peoples of Asia Minor and of the Greeks on both sides of the Ægean Sea. The isolation and consequent independent development of India and of China is one of the most salient and significant facts of history. It was not till the end of the fifteenth century, when the Portuguese reached the Malabar coast, that the Indian peoples began to come into the general movement of the world; for the expedition of Alexander the Great left hardly any permanent result, except upon Buddhist art, and the conquests of Mahmud of Ghazni opened no road to the East from the Mediterranean West. Nor did China, though visited by Italian travellers in the thirteenth century, by Portuguese traders and Jesuit missionaries in the sixteenth and seventeenth, come into effective contact with Europe till near our own time. As the wastes of barren land formed an almost impassable eastern boundary to the West Asian civilisations, so on the west the expanse of sea brought Egypt and to a less extent Assyria (through Phœnicia) into touch with all the peoples who dwelt on the shores of the Mediterranean. The first agents in the diffusion of trade and the arts were the Phœnicians, established at Tyre, Sidon, and Carthage. The next were the Greeks. For more than two thousand years, from B.C. 700 onwards, the Mediterranean is practically the centre of the history of the world, because it is the highway both of commerce and of war. For seven hundred years after the end of the second century B.C., that is to say, while the Roman Empire remained strong, it was also the highway of civil administration. The Saracen conquests of the seventh century cut off North Africa and Syria from Europe, checked transmarine commerce, and created afresh the old opposition of East and West in which a thousand years earlier Herodotus had found the main thread of world history. But it was not till after the discovery of America that the Mediterranean began to yield to the Atlantic its primacy as the area of sea power and sea-borne trade. [Sidenote: Influence of the Seas in History] Bordered by far less fertile and climate-favoured countries, and closed to navigation during some months of winter, the Baltic has always held a place in history far below that of the Mediterranean. Yet it has determined the relations of the North European states and peoples. So, too, the North Sea has at one time exposed Britain to attack from the Danish and Norwegian lords of the sea, and at other times protected her from powerful continental enemies. It may indeed be said that in surrounding Europe by the sea on three sides, Nature has drawn the main lines which the course of events on this smallest but most important of the continents has had to follow. [Sidenote: Magellan and American Politics] Of the part which the great bodies of water have played, of the significance in the oceans of mighty currents like the Gulf Stream, the Polar Current, the Japan Current, the Mozambique Current, it would be impossible to speak within reasonable compass. But two remarks may be made before leaving this part of the subject. One is that man’s action in cutting through an isthmus may completely alter the conditions as given by Nature. The Suez Canal has of late years immensely enhanced the importance of the Mediterranean, already in some degree restored by the decay of Turkish power, by the industrial revival of Italy, and by the French conquests in North Africa. The cutting of a canal at Panama will change the relations of the seafaring and fleet-owning nations that are interested in the Atlantic and the Pacific. And the other remark is that the significance of a maritime discovery, however great at first, may become still greater with the lapse of time. Magellan, in his ever memorable voyage, not only penetrated to and crossed the Pacific, but discovered the Philippine Islands, and claimed them for the monarch who had sent him forth. His appropriation of them for the Crown of Spain, to which during these three centuries and a half they have brought no benefit, has been the cause which has led the republic of the United States to depart from its traditional policy of holding to its own continent by taking them as a prize--a distant and unexpected prize--of conquest. [Illustration: HOW NATURE DETERMINES THE SITES OF CITIES Most towns and communities founded more than 300 years ago were on easily defensible hills, by the side of navigable rivers, or inlets of the sea. Our illustrations show (1) Naples, (2) Bonsuna, (3) Old Port and hill of Marseilles, (4) Monaco, (5) St. Cézaire, and (6) the Greek Monastery of St. Balaam. Photos. by Frith and Underwood & Underwood ] [Illustration: THE SHIFTING OF THE CENTRE OF THE WORLD’S COMMERCE These two maps, which have been very carefully prepared from the most reliable authorities, indicate at a glance the relative importance of the Mediterranean and the Atlantic as highways of commerce in the time of Julius Cæsar, B.C. 102-44. ] [Illustration: HOW THE MEDITERRANEAN HAS GIVEN PLACE TO THE ATLANTIC Here is the contrast to the opposite page. In our time the Atlantic has become the centre of the world’s commerce, and the Mediterranean has sunk in importance. It would be almost deserted but for the routes to India via the Suez Canal. ] A few words may suffice as to what Nature has done towards the formation of nations and States by the configuration of the surface of the dry land--that is to say, by mountain chains and by river valleys. The only natural boundaries, besides seas, are mountains and deserts. Rivers, though convenient frontier lines for the politician or the geographer, are not natural boundaries, but rather unite than dissever those who dwell on their opposite banks. Thus the great natural boundaries in Asia have been the deserts of Eastern Persia, of Turkestan, and of Northern Arabia, with the long Himalayan chain and the savage ranges apparently parallel to the Irawadi River, which separate the easternmost corner of India and Burmah from South-Western China. To a less extent the Altai and Thian Shan, and, to a still smaller extent, the Taurus in Eastern Asia Minor, have tended to divide peoples and States. The Caucasus, which fills the space between two great seas, has been at all times an extremely important factor in history, severing the nomad races of Scythia from the more civilised and settled inhabitants of the valleys of the Phasis and the Kura. Even to-day, when the Tsar holds sway on both sides of this chain, it constitutes a weakness in the position of Russia, and it helps to keep the Georgian races to the south from losing their identity in the mass of Russian subjects. [Sidenote: The Place of Mountains in History] Without the Alps and the Pyrenees, the annals of Europe must have been entirely different. The Alps, even more than the Italian climate, proved too much for the Romano-Germanic Emperors of the Middle Ages, who tried to rule both to the north and to the south of this wide mountain region. The Pyrenees have not only kept in existence the Basque people, but have repeatedly frustrated the attempts of monarchs to dominate both France and Spain. The mass of high moorland country which covers most of the space between the Solway Firth and the lower course of the Tweed has had something to do with the formation of a Scottish nation out of singularly diverse elements. The rugged mountains of Northern and Western Scotland, and the similar though less extensive hill country of Wales, have enabled Celtic races to retain their language and character in both these regions. [Sidenote: What Steam-power has Done] On the other hand, the vast open plains of Russia have allowed the Slavs of the districts which lie round Novgorod, Moscow, and Kiev to spread out among and Russify the Lithuanian and Finnish, to some extent also the Tartar, races, who originally held by far the larger part of that area. So, too, the Ural range, which, though long, is neither high nor difficult to pass, has opposed no serious obstacle to the overflow of population from Russia into Siberia. That in North America the Alleghanies have had a comparatively slight effect upon political history, although they did for a time arrest the march of colonisation, is due partly to the fact that they are a mass of comparatively low parallel ranges, with fertile valleys between, partly to the already advanced civilisation of the Anglo-Americans of the Atlantic seaboard, who found no great difficulty in making their way across, against the uncertain resistance of small and non-cohesive Indian tribes. A far more formidable natural barrier is formed between the Mississippi Valley and the Pacific slope by the Rocky Mountains, with the deserts of Arizona, Utah, Nevada, and Idaho. But the discovery of steam power has so much reduced the importance of this barrier that it does not seriously threaten the maintenance of a united American republic. In one respect the New World presents a remarkable contrast to the Old. The earliest civilisations of the latter seem to have sprung up in fertile river valleys. Those of the former are found not on the banks of streams like the Nile or Euphrates, but on elevated plateaux, where the heat of a tropical sun is mitigated by height above sea level. It was in the lofty lake basin of Tezcuco and Mexico, and on the comparatively level ground which lies between the parallel ranges of the Peruvian and Bolivian Andes, that American races had reached their finest intellectual development, not in the far richer, but also hotter and less healthy river valleys of Brazil, or (unless we are to except Yucatan) on the scorching shores of the Caribbean Sea. Nature was in those regions too strong for man, and held him down in savagery. [Sidenote: How Nature fixes Sites of Cities] In determining the courses of great rivers, Nature has determined the first highways of trade and fixed the sites of many cities. Nearly all the considerable towns founded more than three centuries ago owe their origin either to their possessing good havens on the sea-coast, or to the natural strength of their position on a defensible hill, or to their standing close to a navigable river. Marseilles, Alexandria, New York, Rio de Janeiro, are instances of the first; Athens, Edinburgh, Prague, Moscow, of the second; Bordeaux, Cologne, New Orleans, Calcutta, of the third. Rome and London, Budapest, and Lyons combine the advantages of the second with those of the third. This function of rivers in directing the lines of commerce and the growth of centres of population has become much less important since the construction of railroads, yet population tends to stay where it has been first gathered, so that the fluviatile cities are likely to retain their preponderance. Thus the river is as important to the historian as is the mountain range or the sea. [Sidenote: Climate and Commerce] From the physical features of a country it is an easy transition to the capacities of the soil. The character of the products of a region determines the numbers of its inhabitants and the kind of life they lead. A land of forests breeds hunters or lumbermen; a land of pasture, which is too rough or too arid or too sterile for tillage, supports shepherds or herdsmen probably more or less nomadic. Either kind of land supports inhabitants few in proportion to its area. Fertile and well-watered regions rear a denser, a more settled, and presumably a more civilised population. Norway and Tyrol, Tibet and Wyoming, and the Orange River Colony, can never become so densely peopled as Bengal or Illinois or Lombardy, yet the fisheries of its coast and the seafaring energy of its people have sensibly increased the population of Norway. Thus he who knows the climate and the productive capacity of the soil of any given country can calculate its prospects of prosperity. Political causes may, of course, intervene. Asia Minor and the Valley of the Euphrates, regions once populous and flourishing, are now thinly inhabited and poverty-stricken because they are ruled by the Turks. But these cases are exceptional. Bengal and Lombardy and Egypt have supported large populations under all kinds of government. The products of each country tend, moreover, to establish definite relations between it and other countries, and do this all the more as population, commerce, and the arts advance. When England was a great wool-growing and wool-exporting country, her wool export brought her into close political connection with the wool-manufacturing Flemish towns. She is now a cotton-manufacturing country, needing cotton which she cannot grow at all, and consuming wheat which she does not grow in sufficient quantities. Hence she is in close commercial relations with the United States on one side, which give her most of her cotton and much of her wheat, and with India, from which she gets both these articles, and to which she exports a large part of her manufactured cotton goods. [Sidenote: Common Needs make for Peace] So Rome, because she needed the corn of Egypt, kept Egypt under a specially careful administration. The rest of her corn came from Sicily and North Africa, and the Vandal conquest of North Africa dealt a frightful blow to the declining Empire. In these cases the common interest of sellers and buyers makes for peace, but in other cases the competition of countries desiring to keep commerce to themselves occasions war. The Spanish and Dutch fought over the trade to India in the earlier part of the seventeenth century, when the Portuguese Indies belonged to Spain, as the English and French fought in the eighteenth. And a nation, especially an insular nation, whose arable soil is not large enough or fertile enough to provide all the food it needs, has a powerful inducement either to seek peace or else to be prepared for maritime war. If such a country does not grow enough corn or meat at home, she must have a navy strong enough to make sure that she will always be able to get these necessaries from abroad. Attica did not produce all the grain needed to feed the Athenians, so they depended on the corn ships which came down from the Euxine, and were practically at the mercy of an enemy who could stop those ships. Of another natural source of wealth, the fisheries on the coast of a country, no more need be said than that they have been a frequent source of quarrels and even of war. The recognition of the right of each state to the exclusive control and enjoyment of the sea for three miles off its shores has reduced, but not entirely removed, the causes of friction between the fishermen of different countries. [Sidenote: Minerals and Civilisation] Until recently, the surface of the soil was a far more important source of wealth than was that which lies beneath the surface. There were iron mines among the Chalybes on the Asiatic coast of the Euxine in ancient times; there were silver mines here and there, the most famous being those at Laurium, from which the Athenians drew large revenues, gold mines in Spain and Dacia, copper mines in Elba, tin mines in the south-west corner of Britain. But the number of persons employed in mining and the industries connected therewith was relatively small both in the ancient world and, indeed, down till the close of the eighteenth century. The immense development of coal-mining and of iron-working in connection therewith has now doubled, trebled, or quadrupled the population of large areas in Britain, Germany, France, Belgium, and the United States, adding vastly to the wealth of these countries and stimulating in them the growth of many mechanical arts. This new population is quite different in character from the agricultural peasantry who in earlier days formed the principal substratum of society. Its appearance has changed the internal politics of these countries, disturbing the old balance of forces and accelerating the progress of democratic principles. [Illustration: THE PLACE OF MOUNTAINS IN HISTORY: NATURE’S BARRIERS TO MAN’S EXPANSION Without the Alps the annals of Europe must have been entirely different. The mountains were too much for the emperors of the Middle Ages, although Hannibal, the great Carthaginian general, succeeded in crossing them two centuries before Christ, a feat which Napoleon repeated 2,000 years later. Our engraving illustrates Napoleon crossing the Alps. ] Nor have minerals failed to affect the international relations of peoples and States. It was chiefly for the precious metals that the Spaniards explored the American Continent and conquered Mexico and Peru. It was for the sake of capturing the ships bringing those metals back to Europe that the English sea-rovers made their way to the American coasts and involved England in wars with Spain. It was the discovery in 1885 of extensive auriferous strata unexampled in the certainty of their yield that drew a swarm of foreign immigrants into the Transvaal, whence arose those difficulties between them and the Dutch inhabitants previously established there which, coupled with the action of the wealthy owners of the mines, led at last to the war of 1899 between Britain and the two South African Republics. [Sidenote: Man’s Fight with Nature] The productive capacity of a country is, however, in one respect very different from those great physical features--such as temperature, rainfall, coast configuration, surface character, geological structure, and river system--which have been previously noted. Those features are permanent qualities which man can affect only to a limited extent, as when he reduces the rainfall a little by cutting down forests, or increases it by planting them, or as when he unites an isle, like that of Cadiz, to the mainland, cuts through an isthmus, like that of Corinth, or clears away the bar at a river mouth, as that of the Mississippi has been cleared. [Sidenote: Exhausting the Mineral Wealth] But the natural products of a country may be exhausted and even the productive capacity of its soil diminished. Constant tillage, especially if the same crop be raised and no manure added, will wear out the richest soils. This has already happened in parts of Western America. Still the earth is there; and with rest and artificial help it will recover its strength. But timber destroyed cannot always be induced to grow again, or at least not so as to equal the vigour of primeval forests. Wild animals, once extirpated, are gone for ever. The buffalo and beaver of North America, the beautiful lynxes of South Africa and some of its large ruminants, are irrecoverably lost for the purposes of human use, just as much as the dinornis, though a few individuals may be kept alive as specimens. So, too, the mineral resources of a country are not only consumable, but obviously irreplaceable. Already some of the smaller coalfields of Europe have been worked out, while in others it has become necessary to sink much deeper shafts, at an increasing cost. There is not much tin left in Cornwall, not much gold in the gravel deposits of Northern California. The richest known goldfield of the world, that of the Transvaal Witwatersrand, can hardly last more than thirty or forty years. Thus in a few centuries the productive capacity of many regions may have become quite different from what it is now, with grave consequences to their inhabitants. These are some of the ways in which Nature affects those economic, social, and political conditions of the life of man the changes in which make up history. As we have seen, that which Nature gives to man is always the same, in so far as Nature herself is always the same--an expression which is more popular than accurate, for Nature herself--that is to say, not the laws of Nature, but the physical environment of man on this planet--is in reality always changing. It is true that this environment changes so slowly that a thousand years may be too short a period in which man can note and record some forms of change--such, for instance, as that by which the temperature of Europe became colder during the approach of the glacial period and warmer during its recession--while ten thousand years may be too short to note any diminution in the heat which the sun pours upon the earth, or in the store of oxygen which the earth’s atmosphere holds. [Sidenote: Progress of Modern Invention] [Sidenote: Man Cannot Disregard Nature] But as we have also seen, the relation to man of Nature’s gifts differs from age to age as man himself becomes different, and as his power of using these gifts increases, or his need of them becomes either less or greater. Every invention alters those relations. Water power became less relatively valuable when steam was applied to the generation of motive force. It has become more valuable with the new applications of electricity. With the discovery of mineral dyes, indigo and cochineal are now less wanted than they were. With the invention of the pneumatic tyre for bicycles and carriages, caoutchouc is more wanted. Mountains have become, since the making of railways, less of an obstacle to trade than they were, and they have also become more available as health resorts. Political circumstances may interfere with the ordinary and normal action of natural phenomena. A race may be attracted to or driven into a region for which it is not physically suited, as Europeans have gone to the West Indies, and negroes were once carried into New York and Pennsylvania. The course of trade which Nature prescribes between different countries may be hampered or stopped by protective tariffs; but in these cases Nature usually takes her eventual revenges. They are instances which show, not that man can disregard her, but that when he does so, he does so to his own loss. It would be easy to add further illustrations, but those already given are sufficient to indicate how multiform and pervading is the action upon man of the physical environment, or in other words, how in all countries, and at all times, geography is the necessary foundation of history, so that neither the course of a nation’s growth, nor its relations with other nations, can be grasped by one who has not come to understand the climate, surface, and products of the country wherein that nation dwells. [Sidenote: There is no Unmixed Race left] This conception of the relation of geography to history is, as has been said, the leading idea of the present work, and has furnished the main lines which it follows. It deals with history in the light of physical environment. Its ground plan, so to speak, is primarily geographical, and secondarily chronological. But there is one difficulty in the way of such a scheme, and of the use of such a ground plan, which cannot be passed over. That difficulty is suggested by the fact already noted--that hardly any considerable race, and possibly no great nation, now inhabits the particular part of the earth’s surface on which it was dwelling when a history begins. Nearly every people has either migrated bodily from one region to another, or has received such large infusions of immigrants from other regions as to have become practically a new people. Hence it is rare to find any nation now living under the physical conditions which originally moulded its character, or the character of some at least of its component elements. And hence it follows that when we study the qualities, aptitudes, and institutions of a nation in connection with the land it inhabits, we must always have regard not merely to the features of that land, but also to those of the land which was its earlier dwelling-place. Obviously, this brings a disturbing element into the study of the relations between land and people, and makes the whole problem a far more complicated one than it appeared at first sight. [Sidenote: Nature’s Race Factory] Where a people has migrated from a country whose physical conditions were similar to those under which its later life is spent, or where it had reached only a comparatively low stage of economic and political development before the migration, the difficulties arising from this source are not serious. The fact that the English came into Britain from the lands round the mouth of the Elbe is not very material to an inquiry into their relations to their new home, because climate and soil were similar, and the emigrants were a rude, warlike race. But when we come to the second migration of the English, from Britain to North America, the case is altogether different. Groups of men from a people which had already become highly civilised, had formed a well-marked national character, and had created a body of peculiar institutions, planted themselves in a country whose climate and physical features are widely diverse from those of Britain. If, for the sake of argument, we assume the Algonquin aborigines of Atlantic North America as they were in A.D. 1600 to have been the legitimate product of their physical environment--I say “for the sake of argument,” because it may be alleged that other forces than those of physical environment contributed to form them--what greater contrast can be imagined than the contrast between the inhabitants of New England in this present year and the inhabitants of the same district three centuries earlier, as Nature, and Nature alone, had turned them out of her factory? Plainly, therefore, the history of the United States cannot, so far as Nature and geography are concerned, be written with regard solely, or even chiefly, to the conditions of North American nature. The physical environment in which the English immigrants found themselves on that continent has no doubt affected their material progress and the course of their politics during the three centuries that have elapsed since settlements were founded in Virginia and on Massachusetts Bay. [Sidenote: Beginnings of Race History] But it is not to that environment, but to earlier days, and especially to the twelve centuries during which their ancestors lived in England, that their character and institutions are to be traced. Thus the history of the American people begins in the forests of Germany, where the foundations of their polity were laid, and is continued in England, where they set up kingdoms, embraced Christianity, became one nation, received an influx of Celtic, Danish, and Norman-French blood, formed for themselves that body of customs, laws, and institutions which they transplanted to the new soil of America, and most of which, though changed and always changing, they still retain. The same thing is true of the Spaniards (as also of the Portuguese) in Central and South America. The difference between the development of the Hispano-Americans and that of their English neighbours to the north is not wholly, or even mainly, due to the different physical conditions under which the two sets of colonists have lived. It is due to the different antecedent history of the two races. So a history of America must be a history not only of America, but of the Spaniards, Portuguese, French, and English--one ought in strictness to add of the negroes also--before they crossed the Atlantic. The only true Americans, the only Americans for whom American nature can be deemed answerable, are the aboriginal red men whom we, perpetuating the mistake of Columbus, still call Indians. [Sidenote: Geography as a Basis of History] This objection to the geographical scheme of history writing is no doubt serious when a historical treatise is confined to one particular country or continent, as in the instance I have taken of the Continent of North America. It is, however, less formidable in a universal history, such as the present work, because, by referring to another volume of the series, the reader will find what he needs to know regarding the history of the Spaniards, English, and French in those respective European homes where they have grown to be that which they were when, with religion, slaughter, and slavery in their train, they descended upon the shores of America. Accordingly the difficulty I have pointed out does not disparage the idea and plan of writing universal history on a geographical basis. It merely indicates a caution needed in applying that plan, and a condition indispensable to its utility--viz., the regard that must be had to the stage of progress at which a people has arrived when it is subjected to an environment different from that which had in the first instance helped to form its type. THE GROWTH OF MODERN KNOWLEDGE We have now considered some of the ways in which a universal history, written with special reference to the physical phenomena of the earth as geographical science presents them, may bring into strong relief one large and permanent set of influences which determine the progress or retrogression of each several branch of mankind. Upon the other principles which preside over and direct the composition of such a work, not much need be said. They are, of course, in the main, those which all competent historians will follow in writing the history of any particular people. But a universal history which endeavours to present in a short compass a record of the course of events in all regions and among all peoples, since none can safely be omitted, is specially exposed to two dangers. One is that of becoming sketchy and viewy. When a large object has to be dealt with on a small scale, it is natural to sum up in a few broad generalisations masses of facts which cannot be described or examined in detail. Broad generalisations are valuable when they proceed from a thoroughly trained mind--valuable, even if not completely verifiable, because they excite reflection. But it is seldom possible to make them exact. They necessarily omit most of the exceptions, and thus suggest a greater uniformity than exists. Neurdein THE STONE AGE: HUNTERS RETURNING FROM THE CHASE From the painting by Ferdinand Cormon ] [Sidenote: Need of Care in History] The other danger is that of sacrificing brightness and charm of presentation. When an effort is made to avoid generalisations, and to squeeze into the narrative as many facts as the space will admit, the narrative is apt to become dry, because compression involves the curtailment of the personal and dramatic element. These are the rocks between which every historian has to steer. If he has ample space, he does well to prefer the course of giving all the salient facts and leaving the reader to generalise for himself. If, however, his space is limited, as must needs be the lot of those who write a universal history, the impossibility of going into minute detail makes generalisations inevitable, for it is through them that the result and significance of a multitude of minor facts must be conveyed in a condensed form. [Sidenote: New Minds and New Facts] All the greater, therefore, becomes the need for care and sobriety in the forming and setting forth every summarising statement and general conclusion or judgment. Probably the soundest guiding principle and best safeguard against error is to be found in shunning all preconceived hypotheses which seek to explain history by one set of causes, or to read it in the light of one idea. The habit of magnifying a single factor, such as the social factor, or the economic, or the religious, has been a fertile source of weakness in historical writing, because it has made the presentation of events one-sided, destroying that balance and proportion which it is the highest merit of any historian to have attained. Theory and generalisation are the life-blood of history. They make it intelligible. They give it unity. They convey to us the instruction which it always contains, together with so much of practical guidance in the management of communities as history is capable of rendering. But they need to be applied with reserve, and not only with an impartial mind, but after a painstaking examination of all the facts--whether or no they seem to make for the particular theory stated--and of all the theories which any competent predecessor has propounded. For the historian, though he must keep himself from falling under the dominion of any one doctrine by which it is sought to connect and explain phenomena, must welcome all the light which any such doctrine can throw upon facts. Even if such a doctrine be imperfect, even if it be tainted by error, it may serve to indicate relations between facts, or to indicate the true importance of facts, which previous writers had failed to observe, or had passed too lightly over. It is thus that history always needs to be re-written. History is a progressive science, not merely because new facts are constantly being discovered, not merely because the changes in the world give to old facts a new significance, but also because every truly penetrating and original mind sees in the old facts something which had not been seen before. A universal history is fitted to correct such defects as may be incident to that extreme specialism in historical writing which is now in fashion. The broad and concise treatment which a history of all times and peoples must adopt naturally leads to efforts to characterise the dominant features and tendency of an epoch or a movement, whether social, economic, or political. [Sidenote: The Side Streams of History] Yet even here there is a danger to be guarded against. No epoch, no movement, is so simple as it looks at first sight, or as one would gather from even the most honest contemporary writer. There is always an eddy at the side of the stream; and the stream itself is the resultant of a number of rivulets with different sources, whose waters, if the metaphor may be extended, are of different tints. Let any man study minutely a given epoch, such as that of the Reformation in Germany, or that of the Revolutionary War in America, and he will be surprised to find how much more complex were the forces at work than he had at first supposed, and on how much smaller a number of persons than he had fancied the principal forces did in fact directly operate. Or let any one--for this is perhaps the best, if the most difficult, method of getting at the roots of this complexity--study thoroughly and dispassionately the phenomena of his own time. Let him observe how many movements go on simultaneously, sometimes accelerating, sometimes retarding, one another, and mark how, the more fully he understands this complex interlacing, so much the less confident do his predictions of the future become. He will then realise how hard it is to find simple explanations and to deliver exact statements regarding critical epochs in the past. Mercier THE FIRST INDUSTRIES: POTTERY From the painting by Ferdinand Cormon ] Mercier THE FIRST INDUSTRIES: THE FORGE From the painting by Ferdinand Cormon ] [Sidenote: The Main Stream of History] Nevertheless, the task of summarising and explaining is one to which the writer of a History of the World must address himself. If he has the disadvantage of limited space, he has the advantage of being able to assume the reader’s knowledge of what has gone before, and to invite the reader’s attention to what will come after. Thus he stands in a better position than does the writer who deals with one country or one epoch only for making each part of history illustrate other parts, for showing how similar social tendencies, similar proclivities of human nature, work similarly under varying conditions and are followed by similar, though never identical, results. He is able to bring out the essential unity of history, expunging from the reader’s mind the conventional and often misleading distinctions that are commonly drawn between the ancient, the mediæval, and the modern time. He can bring the contemporaneous course of events in different countries into a fruitful relation. And in the case of the present work, which dwells more especially on the geographical side of history, he can illustrate from each country in succession the influence of physical environment on the formation of races and the progress of nations, the principles which determine the action of such environment being everywhere similar, though the forms which that action takes are infinitely various. Is there, it may be asked, any central thread in following which the unity of history most plainly appears? Is there any process in tracing which we can feel that we are floating down the main stream of the world’s onward movement? If there be such a process, its study ought to help us to realise the unity of history by connecting the development of the numerous branches of the human family. One such process has already been adverted to and illustrated. It is the gradual and constant increase in man’s power over Nature, whereby he is emancipated more and more from the conditions she imposes on his life, yet is brought into an always closer touch with her by the discovery of new methods of using her gifts. Two other such processes may be briefly examined. One goes on in the sphere of time, and consists in the accumulation from age to age of the strength, the knowledge, and the culture of mankind as a whole. The other goes on in space as well as in time, and may be described as the contraction of the world, relatively to man. [Sidenote: The Great Increase of Population] The accumulation of physical strength is most apparent in the increase of the human race. We have no trustworthy data for determining the population, even of any one civilised country, more than a century and a half ago; much less can we conjecture that of any country in primitive or prehistoric times. It is clear, however, that in prehistoric times--say, six or seven thousand years ago, there were very few men on the earth’s surface. The scarcity of food alone would be sufficient to prove that; and, indeed, all our data go to show it. Fifty years ago the world’s population used to be roughly conjectured at from seven to nine hundred millions, two-thirds of them in China and India. It is now estimated at over fifteen hundred millions. That of Europe alone must have tripled within a century, and can hardly be less than four hundred millions. That of North America may have scarcely exceeded four or five millions in the time of Christopher Columbus, or at the date of the first English settlements, though we have only the scantiest data for a guess. It may now be 130,000,000, for there are over a hundred millions in the United States alone, about fifteen in Mexico, and eight in Canada, besides the inhabitants of Central America. [Sidenote: The Prolific Power of White People] [Sidenote: Physical & Intellectual Power] The increase has been most swift in the civilised countries, such as Britain, Germany, Russia, and the United States; but it has gone on in India also since India came under British rule (famines notwithstanding), and in the regions recently colonised by Europeans, such as Australia, Siberia, and Argentina, the disappearance of aborigines being far more than compensated for by the prolific power of the white immigrants. Some regions, such as Asia Minor and parts of North Africa, are more thinly peopled now than they were under the Roman Empire, and both China and Peru may have no larger population than they had five, or ten, or fifteen centuries ago. But taking the world at large, the increase is enormous, and will apparently continue. Even after the vacant cultivable spaces which remain in the two Americas, Northern Asia, and Australasia have been filled, the discovery of new modes of enlarging the annually available stock of food may maintain the increase. It is most conspicuous among the European races, and is, of course, due to the greater production in some regions of food, and in others of commodities wherewith food can be purchased. It means an immense addition to the physical force of mankind in the aggregate, and to the possibilities of intellectual force also--a point to be considered later. And, of course, it also means an immense and growing preponderance of the civilised white nations, which are now probably one half of mankind, and may, in another century, when they have risen from about five hundred to, possibly, one thousand or fifteen hundred millions, be nearly two-thirds. [Sidenote: Modern Man Stronger than his Ancestors] As respects the strength of the average individual man, the inquiry is less simple. Palæolithic man and neolithic man were apparently (though here and there may have been exceptions) comparatively feeble creatures, as are the relics of the most backward tribes known to us, such as the Veddas of Ceylon, the Bushmen, the Fuegians. Some savages, as, for instance, the Patagonians, are men of great stature, and some of the North American Indians possess amazing powers of endurance. The Greeks of the fifth century B.C., and the Teutons of the time of Julius Cæsar, had reached a high physical development. Pheidippides is said to have traversed one hundred and fifty miles on foot in forty-eight hours. But if we think of single feats of strength, feats have been performed in our own day--such as Captain Webb’s swimming across the Straits of Dover--equal to anything recorded from ancient or mediæval times. To swim across the much narrower Hellespont was then deemed a surprising exploit. Nor do we know of any race more to be commended for physical power and vigour of constitution than the American backwoodsmen of Kentucky or Oregon to-day. The swords used by the knights of the fifteenth century have usually handles too small for many a modern English or German hand to grasp. [Sidenote: America’s Mingled Races] Isolated feats do not prove very much, but there is good reason to believe that the average European is as strong as ever he was, and probably more healthy, at least if longevity is a test of health. One may fairly conclude that with better and more abundant food, the average of stature and strength has improved over the world at large, so that in this respect also the force of mankind as a whole has advanced. Whether this advance will continue is more doubtful. In modern industrial communities the law of the survival of the fittest may turn out to be reversed, for it is the poorer and lower sections of the population that marry at an early age, and have the largest families, while prudential considerations keep down the birth-rate among the upper middle-class. In Transylvania, for instance, the Saxons are dying out, because very few children are born to each pair, while the less educated and cultured Rumans increase fast. In North America, the Old New England stock of comparatively pure British blood has begun to be swamped by the offspring of the recent immigrants, mostly Irish or French Canadians; and although the sons of New England, who have gone West, continue to be prolific, it is probable that the phenomena of New England will recur in the Mississippi Valley, and that the newcomers from Europe who form the less cultivated strata of the population--Irish, Germans, Italians, Czechs, Poles, Slovaks, Rumans--will contribute an increasing proportion of the inhabitants. Some of these, and especially the Irish and the Germans and the Scandinavians, are among the best elements in the American population, and have produced men of the highest distinction. But the average level among them of versatile aptitude and of intellectual culture is slightly below that of the native Americans. Now, the poorer sections are in most countries, though of course not always to the same extent, somewhat inferior in physical as well as in mental quality, and more prone to suffer from that greatest hindrance to physical improvement, the abuse of alcoholic drinks. We come next to another form of the increase of human resources, the accumulation of knowledge, and of what may be called intellectual culture and capacity, for it is convenient to distinguish these two latter from knowledge. [Illustration: PIONEERS OF MODERN CIVILISATION The discovery of precious metals is a great factor in progress. Seekers after gold are chief among the pioneers who help to carry civilisation into new lands. ] [Sidenote: Inventions Mean Progress] In knowledge there has been an advance, not merely a tolerably steady and constant advance, but one which has gone on with a sort of geometrical progression, moving the faster the nearer we come to our own time. Whatever may have befallen in the prehistoric darkness, history knows of only one notable arrest or setback in the onward march--that which marks the seventh, eighth, and ninth centuries of the Christian era. Even this set-back was practically confined to Southern and Western Europe, and affected only certain departments of knowledge. It did not, save, perhaps, as regards a few artistic processes, extinguish that extremely important part of the previously accumulated resources of mankind which consisted in the knowledge of inventions. It is in respect of inventions, especially mechanical and physical or chemical inventions, that the accumulation of knowledge has been most noteworthy and most easy to appreciate. A history of inventions is a history of the progress of mankind, of a progress to which every race may have contributed in primitive times, though all the later contributions have come from a few of the most civilised. Every great invention marks one onward step, as one may see by enumerating a few, such as the use of fire, cooking, metal working, the domestication of wild animals, the tillage of the ground, the use of plough and mattock and harrow and fan, the discovery of plants or trees useful for food or for medicine, the cart, the wheel, the water-mill (overshot, undershot, and turbine), the windmill, the distaff (followed long, long after by the spinning-wheel), the loom, dyestuffs, the needle, the potter’s wheel, the hydraulic press, the axe-handle, the spear, the bow, the shield, the war-chariot, the sling, the cross-bow, the boat, the paddle, the oar, the helm, the sail, the mariner’s compass, the clock, picture-writing, the alphabet, parchment, paper, printing, photography, the sliding keel, the sounding-lead, the log, the brick, mortar, the column, the arch, the dome, till we come down to explosives, the microscope, the cantilever, and the Röntgen rays. [Illustration: THE FIRST SETTLEMENT OF A NEW CITY Many flourishing cities in South Africa, Australia, and America have grown up around the sites where the first gold-seekers pegged out their claims in unexploited territories and began digging for the precious metal. ] The history of the successive discovery, commixture, and applications of the metals, from copper and bronze down to manganese, platinum, and aluminium, or of the successive discovery and utilisation of sources of power--the natural sources, such as water and wind, the artificially procured, such as steam, gas, and electricity--or of the production and manufacture of materials available for clothing, wool, hair, linen, silk, cotton, would show how every step becomes the basis for another step, and how inventions in one department suggest or facilitate inventions in another. Recent discoveries in surgery and medicine, such as the use of antiseptics, tend to improve health and to prolong life; and in doing so, they increase the chances of further discoveries being made. [Sidenote: The Prolonging of Life] Who can tell what the world may have lost by the early death of many a man of genius? One peculiar line of discovery which at first seemed to have nothing to do with practice has proved to be of signal service; the working out of mathematical methods of calculation by means of which the mechanical and physical sciences have in recent times made a progress in their practical application undreamt of by those who laid the foundations of geometry and algebra many centuries ago. It may, indeed, be said that all the sciences need one another, and that none has been without its utilities for practice, since even that which deals with the heavenly bodies has been used for the computation of time, was used by the agriculturist before he had any calendars to guide him, and has been of supreme value to the navigator. It has also been suggested that an observation of sun spots may enable the advent of specially hot seasons, involving droughts, to be predicted. Another kind of knowledge also grows by the joint efforts of many peoples, that which records the condition of men in the past and the present, including history, economics, statistics, and the other so-called social sciences. This kind also is useful for practice, and has led to improvements by which nearly all nations have profited, such as an undebased currency, banking and insurance, better systems of taxation, corporations, and joint stock companies. With this we may couple the invention of improved political institutions. The accumulation of knowledge, especially of scientific knowledge applied to the exploitation of the resources of Nature, means the accumulation of wealth--that is to say, of all the things which men need or use. The total wealth of the world must have at least quadrupled or quintupled within the last hundred years. Nearly all of it is in the hands or under the control of the civilised nations of European stock, among whom the United States stands foremost, both in rate of economic growth and in the absolute quantity of values possessed. [Sidenote: Knowledge Means Wealth] Two further observations belong to this part of the subject. One is that this stock of useful knowledge, the accumulation of which is the central fact of the material progress as well as of the intellectual history of mankind, now belongs to (practically) all races and states alike. Some, as we shall note presently, are more able to use it than others, but all have access to it. This is a new fact. It is true that most races have contributed something to the common stock; and that even among the civilised peoples, no one or two or three (except possibly the Greeks as respects ancient times) can claim to have contributed much more than the others. But in earlier ages there were peoples or groups of peoples who were for a time the sole possessors of inventions which gave them great advantages, especially for war. Superior weapons as well as superior drill enabled Alexander the Great, and afterward the Romans, to conquer most of the civilised world. Horses and firearms, with courage and discipline, enabled two Spanish adventurers to seize two ancient American empires with very scanty forces, as they enabled a handful of Dutch Boers to overcome the hosts of Mosilikatze and Dingaan. So there were formerly industrial arts known to or practised by a few peoples only. But now all inventions, even those relating to war, are available even to the more backward races, if they can learn how to use them or can hire white men to do so for them. The facilities of communication are so great, the means of publicity so abundant, that everything becomes speedily known everywhere. [Sidenote: Inventions are now Universal] The other observation is that there is now no risk that any valuable piece of knowledge will be lost. Every public event that happens, as well as every fact of scientific consequence, is put on record, and that not on a single stone or in a few manuscripts, but in books, of which so many copies exist that even the perishable nature of the material will not involve the loss of the contents, since, if these contents are valuable, they will be transferred to and issued in other books, and so _ad infinitum_. Thus every process of manufacture is known to so many persons that while it continues to be serviceable it is sure to be familiar and transmitted from generation to generation by practice as well as by description. We must imagine a world totally different from the world we know in order to imagine the possibility of any diminution, indeed of any discontinuance of the increase, of this stock of knowledge which the world has been acquiring, and which is not only knowledge but potential wealth. When one passes from knowledge considered as a body of facts ascertained and available for use to the thing we call intellectual aptitude or culture--namely, the power of turning knowledge to account and of producing results in spheres other than material--and when we inquire whether mankind has made a parallel advance in this direction, it becomes necessary to distinguish three different kinds of intellectual capacity. The first may be called the power of using scientific methods for investigating phenomena, whether physical or social. [Sidenote: No Decrease of Knowledge is now Likely] The second is the power of speculation, applied to matters which have not hitherto been found capable of examination by the methods of science, whether observational, experimental, or mathematical. The third is the power of intellectual creation, whether literary or artistic. The methods of scientific inquiry may almost be classed with the ascertained facts of science or with inventions, as being parts of the stock of accumulated knowledge built up by the labour of many generations. They are known to everybody who cares to study them, and can be learnt and applied by everybody who will give due diligence. Just as every man can be taught to fire a gun, or steer a ship, or write a letter, though guns, helms, and letters are the result of discoveries made by exceptionally gifted men, so every graduate in science of a university can use the methods of induction, can observe and experiment with a correctness which a few centuries ago even the most vigorous minds could scarcely have reached. [Sidenote: Original Thinkers are still Rare] Because the methods have been so fully explained and illustrated as to have grown familiar, a vast host of investigators, very few of whom possess scientific genius, are at work to-day extending our scientific knowledge. So the methods of historical criticism--so the methods of using statistics--are to-day profitably applied by many men with no such original gift as would have made them competent critics or statisticians had not the paths been cut by a few great men and trodden since by hundreds of feet. All that is needed is imitation--intelligent and careful imitation. Nevertheless, there remains this sharp contrast between knowledge of the facts of applied science and knowledge of the methods, that whereas there is no radical difference between the ability of one man and that of another to use a mechanical invention, such as a steam plough or an electric motor-car, there is all the difference in the world between the power of one intellect and another to use a method for the purposes of fresh discovery. Knowledge fossilised in a concrete invention or even in a mathematical formula is a sort of tool ready to every hand. But a method, though serviceable to everybody, becomes eminently fruitful only when wielded by the same kind of original genius as that which made discoveries by the less perfect methods of older days. This is apparent even in inquiries which seem to reside chiefly in collection and computation. Everybody tries nowadays to use statistics. Many people do use them profitably. But the people who by means of statistics can throw really fresh and brilliant light on a problem are as few as ever they were. [Sidenote: Advantage of Modern over Old Thinkers] When we turn to the exercise of speculative thought on subjects not amenable to strictly scientific--that is to say, to exact--methods, the gain which has come to mankind by the labour of past ages is of a different order. Metaphysics, ethics, and theology, to take the most obvious examples, are all of them the richer for the thoughts of philosophers in the past. A number of distinctions have been drawn, and a number of classifications made, a number of confusions, often verbal, have been cleared up, a number of fallacies detected, a number of technical terms invented, whereby the modern speculator enjoys a great advantage over his predecessor. His mind has been clarified, and many new aspects of the old problems have been presented, so that he is better able to see all round the old problems. [Sidenote: The Living Thought of Past Ages] None of the great thinkers, from Pythagoras down to Hegel, has left metaphysics where he found it. Yet none can be said to have built on the foundations of his predecessors in the same way as the mathematicians and physicists and chemists have added to the edifice they found. What the philosophers have done is to accumulate materials for the study of man’s faculties and modes of thinking, and of his ideas regarding his relations to the universe, while also indicating various methods by which the study may be pursued. Each great product of speculative thought is itself a part of these materials, and for that reason never becomes obsolete, as the treatises of the old physicists and chemists have mostly become. Aristotle, for instance, has left us books on natural history, on metaphysics and ethics, and on politics. Those on natural history are mere curiosities, and no modern biologist or zoologist needs them. Those on metaphysics and ethics still deserve the attention of the student of philosophy, though he may in a certain sense be said to have got beyond them. The treatise on politics still keeps its place beside Montesquieu, Burke, and Tocqueville. Or, to take a thinker who like Aristotle seems very far removed from us, though fifteen hundred years later in date, St. Thomas of Aquinum discusses questions from many of which the modern world has moved away, and discusses them by methods which many do not now use, starting from premises which many do not accept. But he marks a remarkable stage in the history of human thought, and as a part of that history, and as an example of extraordinary dialectical ingenuity and subtlety, he remains an object of interest to those least in agreement with his conclusions. [Sidenote: Every Great Thinker Affects Others] Every great thinker affects other thinkers, and propagates the impulse he has received, though perhaps in a quite different direction. The teaching of Socrates was the starting point for nearly all the subsequent schools of Greek philosophy. Hume became the point of departure for Kant, who desired to lay a deeper foundation for philosophy than that which Hume seemed to have overturned. All these great ones have not only enriched us, but are still capable of stimulating us. But they have not improved our capacity for original thinking. The accumulation of scientific knowledge has, as already observed, put all mankind in a better position for solving further physical problems and establishing a more complete dominion over Nature. The accumulation of philosophic thought has had no similar effect. In the former case each man stands, so to speak, on the shoulders of his predecessors. In the latter he stands on his own feet. The value of future contributions to philosophy will depend on the original power of the minds that make them, and only to a small extent (except by way of stimulus) on what such minds may have drawn from those into whose labours they have entered. [Sidenote: Ebb-Tides of Intellectual Culture] When we come to the products of literary and artistic capacity, we find an even vaster accumulation of intellectual treasure available for enjoyment, but a still more marked absence of connection between the amount of treasures possessed and the power of adding fresh treasures to them. Since writing came into use, and, indeed, even in the days when memory alone preserved lays and tales, every age and many races have contributed to the stock. There have been ebbs and flows both in quantity and quality. The centuries between A.D. 600 and A.D. 1100 have left us very little of high merit in literature, though something in architecture; and the best of that little in literature did not come from the seats of Roman civilisation in Italy, France, Spain, and the East Roman Empire. Some periods have seen an eclipse of poetry, others an eclipse of art or a sterility in music. Literature and the arts have not always flourished together, and musical genius in particular seems to have little to do with the contemporaneous development of other forms of intellectual power. The quantity of production bears no relation to the quality, not even an inverse relation; for the pessimistic notion that the larger the output the smaller is the part which possesses brilliant excellence, has not been proved. Still less does the amount of good work produced in any given area depend upon the number of persons living in that area. Florence, between A.D. 1250 and A.D. 1500 gave birth to more men of first-rate poetical and artistic genius than London has produced since 1250; yet Florence had in those two and a half centuries a population of probably only from forty to sixty thousand. And Florence herself has since A.D. 1500 given birth to scarcely any distinguished poets or artists, though her population has been larger than it was in the fifteenth century. Mansell THE MIND OF THE ANCIENT WORLD Aristotle (B.C. 384-322) whose influence is greater in some lines than that of St. Thomas of Aquinum, who represents mediæval thought, 1500 years later. ] The increase in the world’s stock of intellectual wealth is one of the most remarkable facts in history, for it represents a constant increase in the means of enjoyment. Such losses as there have been nearly all occurred during the Dark Ages; but there is now little risk that anything of high literary or musical value will perish, though, of course, works of art, and especially buildings and carvings, suffer or vanish. The increase does not, however, tend to any strengthening of the creative faculty. There is a greater abundance of models of excellence, models of which form the taste, afford a stimulus to sensitive minds, and establish a sort of technique with well-known rules. The principles of criticism are more fully investigated. The power of analysis grows, and the appreciation both of literature and of art is more widely diffused. Their influence on the whole community becomes greater, but the creative imagination which is needed for the production of original work becomes no more abundant and no more powerful. It may, indeed, be urged, though our data are probably insufficient for a final judgment, that the finer qualities of poetry and of pictorial and plastic art tend rather to decline under the more analytic habit of mind which belongs to the modern world. Simplicity, freshness, spontaneity come less naturally to those who have fallen under the pervasive influence of this habit. Mansell THE MIND OF THE MEDIÆVAL WORLD St. Thomas of Aquinum, 1500 years later than Aristotle, represents mediæval thought. St. Thomas, however, influences the life and thought of many thousands to-day. ] [Sidenote: Effect of Thought on Mankind] There remains one other way in which the incessant play of thought may be said to have increased or improved the resources of mankind. Certain principles or ideas belonging to the moral and social sphere--to the moral sphere by their origin, to the social sphere by their results--make their way to a more or less general acceptance, and exert a potent influence upon human life and action. They are absent in the earliest communities of which we know, or are present only in germ. They emerge, sometimes in the form of customs gradually built up in one or more peoples, sometimes in the utterances of one gifted mind. Sometimes they spread impalpably; sometimes they become matter for controversy, and are made the battle-cries of parties. Sometimes they end by being universally received, though not necessarily put into practice. Sometimes, on the other hand, they continue to be rejected in one country, or by one set of persons in a country, as vehemently as they are asserted by another. As instances of these principles or ideas or doctrines, whatever one is to call them, the following may be taken: The condemnation of piracy, of slavery, and of treaty-breaking, of outrages on the bodies of dead enemies, of cruelty to the lower animals, of the slaughter of prisoners in cold blood, of polygamy, of torture to witnesses or criminals; the recognition of the duty of citizens to obey the laws, and of the moral responsibility of rulers for the exercise of their power, of the right of each man to hold his own religious opinion and to worship accordingly, of the civil (though not necessarily of the political) equality of all citizens; the disapproval of intoxication, the value set upon female chastity, the acceptance of the social and civil (to which some would add the political) equality of women. [Sidenote: Men who Contributed to Progress] [Sidenote: Slavery was Destroyed by Sentiment] All these dogmas or ideas or opinions--some have become dogmas in all civilised peoples, others are rather to be described as opinions whose truth or worth is denied or only partially admitted--are the slow product of many generations. Most of them are due to what we may call the intelligence and sentiment of mankind at large, rather than to their advocacy by any prominent individual thinkers. The teachings of such thinkers have, of course, done much to advance them. Everybody would name Socrates and Confucius as among the men who have contributed to their progress; some would add such names as those of Mohammed and St. Francis of Assisi. Christianity has, of course, made the largest contributions. How much is due to moral feeling, how much to a sense of common utility, cannot be exactly estimated. Economic reasonings and practical experience would have probably in the long run destroyed slavery, but it was sentiment that did in fact destroy it in the civilised States where it had longest survived. How much these doctrines, even in the partial and imperfect application which most of them have secured, have done for humanity may be perceived by anyone who will imagine what the world would be if they were unknown. They form one of the most substantial additions made to what may be called the intellectual and moral capital with which man has to work this planet and improve his own life upon it. And the most interesting and significant crises in history are those which have turned upon the recognition or application of principles of this kind. The Reformation of the sixteenth century, the French Revolution, the War of Secession in the United States, are familiar modern examples. [Sidenote: Intellect Mightier than Population] Putting all these forms of human achievement together--the extension of the scientific knowledge of Nature with consequent mastery over her, the scientific knowledge of social phenomena in the past and the present, the records of philosophic speculation, the mass of literary and artistic products, the establishment, however partial and imperfect, of regulative moral and political principles--it will be seen that the accumulation of this vast stock of intellectual wealth has been an even more important factor than the increase of population in giving man strength and dignity over against Nature, and in opening up to him an endless variety of modes of enjoying life--that is to say, of making it yield to him the most which its shortness and his own physical infirmities permit. The process by which this accumulation has been carried along is the central thread of history. The main aim of a history of the world must be to show what and how each race or people has contributed to the general stock. To this aim political history, ecclesiastical history, economic history, the history of philosophy, and the history of science, are each of them subordinate, though it is only through them that the process can be explained. In these last few pages intellectual progress has been considered apart from the area in which it has gone on, and apart from the conditions imposed on it by the natural features of that area. A few words are, however, needed regarding its relation to the surface of the earth. The movement of civilisation must be considered from the side of space as well as from that of time. [Sidenote: Contraction of the World] Space is a material element in the inquiry because it has divided the families of mankind from one another. Some families, such as the Chinese and the Peruvians, have developed independently, some, such as the South and West European peoples, in connection with, or perhaps in dependence on, the development of other races or peoples. Hence that which each achieved was in some cases achieved for itself only, in other cases for its neighbours as well. The contributions made by different races have--at any rate during the last four thousand years, and probably in earlier days also--been very unequal; yet none can have failed to contribute something if only by way of influencing the others. Inequality in progress would seem to have become more marked in the later than in the earlier periods. Indeed, some races, such as those of Australia, appear during many centuries, possibly owing to their isolation, to have made no progress at all. They may even have receded. When we regard the evolution and development of man from the side of his relations to space, three facts stand out--the contraction of the world, the overflow of the more advanced races, and the consequent diffusion all over the world of what is called civilisation. By the contraction of the world, I mean the greater swiftness, ease, and safety with which men can pass from one part of it to another, or communicate with one another across great intervening spaces. This has the effect of making the world smaller for most practical purposes, while the absolute distance in latitude and longitude remains the same. The progress of discovery is worth tracing, for it shows how much larger the small earth, which was known to the early nations, must have seemed to them than the whole earth, which we know, seems to us. THE ARTISTIC GENIUS OF TWO CITIES A COMPARISON OF THE NATIVE POETS & ARTISTS OF FLORENCE & LONDON “The quantity of production,” says Mr. Bryce, “bears no relation to the quality. Still less does the amount of good work produced in any given area depend upon the number of persons living in that area. Florence between A.D. 1250 and A.D. 1500 gave birth to more men of first-rate poetical and artistic genius than London has produced since 1250; yet Florence had in those two and a half centuries a population of probably only from forty to sixty thousand. And Florence herself has since A.D. 1500 given birth to scarcely any distinguished poets or artists, though her population has been larger than it was in the fifteenth century.” THE GENIUS OF THE GOLDEN AGE OF FLORENCE, 1250 TO 1500, FAR EXCEEDED THAT OF LONDON FROM 1250 TO THE PRESENT DAY Poets and Artists Born in Florence from 1250-1500 Alberti, Leon Battista, 1404-1472, architect, painter Albertinelli, Mariotto, 1474-1515, painter Andrea del Sarto, 1487-1531, painter Angelico da Fiesole, Fra Giovanni, 1387-1455, painter Botticelli, Alessandro, 1447-1510, painter Cavalcanti, Guido, 1255-1300, poet, philosopher Cimabue, Giovanni, 1240-1302, painter Credi, Lorenzo di, 1459-1537, painter Dante, Alighieri, 1265-1321, poet Donatello, 1386-1466, sculptor and painter Ghiberti, Lorenzo, 1378-1455, sculptor Ghirlandajo, Domenico, 1449-1494, painter Gozzoli, Benozzo, 1420-1498, painter Leonardo da Vinci, 1452-1519, painter, sculptor Lippi, Fra Filippo, 1412-1469, painter Lippi, Filippino, 1459-1504, painter Lorenzo, Don, 1370-1425, painter Medici, Lorenzo de, 1448-1492, poet Orcagnia, Andrea di Cione, 1329-1368? sculptor, painter Perugino, Vannucci Pietro, 1446-1524, painter Pesellino, Francesco di, 1422-1457, painter Pesello, Giuliano, 1367-1446, painter, sculptor Pollajuolo, Antonio, 1429-1498, sculptor, painter Pollajuolo, Piero, 1443-1496, sculptor, painter Robbia, Andrea della, 1437-1528, sculptor Robbia, Luca della, 1399-1482, sculptor Rossi, Giovanni Battista de, 1494-1541, sculptor, painter Ruccellai, Giovanni, 1475-1525, poet Spinello, Aretino, 1334-1410, painter Ucello, Paolo, 1397-1475, painter Verocchio, Andrea, 1435-1488, sculptor, painter THE LAST FOUR HUNDRED YEARS OF FLORENTINE CULTURE HAVE BEEN LESS PRODUCTIVE THAN THE PRECEDING TWO AND A HALF CENTURIES Poets and Artists Born in Florence since 1500 Allori, Christofano, 1577-1621, painter Bronzino, Angelo, 1502-1572, painter Cellini, Benvenuto, 1500-1571, sculptor Cigoli, Luigi Cardi da, 1559-1613, painter Cortona, Pietro da, 1596-1669, architect, painter Dolci, Carlo, 1616-1686, painter Doni, Antonio Francesco, 1513-1574, author Furini, Francesco, 1604-1646, painter Ligozzi, Jacobino, 1543-1627, painter Poccetti, Bernardino, 1542-1612, painter Salviati, Francesco, 1510-1563, painter San Giovanni, Giovanni da, 1599-1636, painter Santi di Tito, 1538-1603, painter Tacco, Pietro, 1580-1640, sculptor Venusti, Marcello, 1515-1579, painter The Only Great Poet Born in London from 1250-1500 Chaucer, Geoffrey, 1328-1400 Poets and Artists Born in London since 1500 Blake, William, 1757-1827, poet and painter Browning, Robert, 1812-1889, poet Byron, Geo. Gordon Noel, Lord, 1788-1824, poet Defoe, Daniel, 1659-1731, author Ford, Edward Onslow, 1852-1901, sculptor Gilbert, Alfred, R.A., 1854- --, sculptor Gray, Thomas, 1716-1771, poet Hogarth, William, 1697-1764, painter Hood, Thomas, 1799-1845, poet Hunt, William Holman, 1827-1910, painter Jonson, Ben, 1573-1637, poet and dramatist Keats, John, 1795-1821, poet Lamb, Charles, 1775-1834, essayist Linnell, John, 1792-1882, painter Lucas, John Seymour, 1849- --, painter Milton, John, 1608-1674, poet Morland, George, 1763-1804, painter Pope, Alexander, 1688-1744, poet Richmond, Sir William Blake, 1843- --, painter Rossetti, Dante Gabriel, 1828-1882, poet, painter Ruskin, John, 1819-1900, author and art critic Spenser, Edmund, 1552-1599, poet Stothard, Thomas, 1755-1834, painter, illustrator Swinburne, Algernon, 1837-1909, poet Walker, Frederick, 1840-1875, painter Watts, George F., 1817-1904, painter, sculptor [Sidenote: The Small World of the Ancients] The most ancient records we possess from Assyria, Egypt, Palestine, and from the Homeric poems, show how very limited was the range of geographical knowledge possessed by that small civilised world from which our own civilisation has descended. Speaking roughly, that knowledge seems in the tenth century B.C. to have extended about one thousand miles in each direction from the Isthmus of Suez. However, the best point of departure for the peoples of antiquity is the era of Herodotus, who travelled and wrote B.C. 460-440. The limits of the world as he knew it were Cadiz and the Straits of Gibraltar on the west, the Danube and the Caspian on the north, the deserts of Eastern Persia on the east, and the Sahara on the south, with vague tales regarding peoples who lived beyond, such as Indians far beyond Persia, and pygmies beyond the Sahara. He reports, however, not without hesitation, a circumnavigation of Africa by Phœnicians in the service of Pharaoh Necho. [Illustration: THE FIRST KNOWN MAP OF THE WORLD This Babylonian map is probably of the eighth century B.C. The two circles are supposed to represent the ocean, while the River Euphrates and Babylon are shown inside them. The upper part of the tablet is a cuneiform inscription. ] Discovery advanced very slowly for many centuries, though the march of Alexander opened up part of the East, while the Roman conquests brought the Far North-West, including Britain, within the range of civilisation; and occasional voyages, such as that of Hanno along the coast of West Africa, that of Nearchus through the Arabian Sea, and that of Pythias to the Baltic, added something to knowledge. Procopius in A.D. 540 can tell us little more regarding the regions beyond Roman influence than Strabo does five and a half centuries earlier. The journeys of Marco Polo and Rubruquis throw only a passing light on the Far East. It is with the Spanish occupation of the Canary Isles, beginning in 1602, and with the Portuguese voyages of the fifteenth century, that the era of modern discovery opens. The re-discovery of America in 1492, for it had been already visited by the Northmen of Greenland and Iceland in the eleventh century, and the opening of the Cape route to India in 1497-1498, were hardly equal to the exploit of Magellan, whose circumnavigation of the globe in 1519-1520 marks the close of this striking period. Thereafter discovery proceeds more slowly. Some of the isles of the central and southern Pacific were not visited till the middle of the eighteenth century, and the north-west coast of America as well as the north-east Coast of Asia, remained little known till an even later date. Those explorations of the interior of North America, of the interior of Africa, of the interior of Australia, and of East Central Asia, which have completed our knowledge of the earth, belong to the nineteenth century. The first crossing of the North American Continent north of latitude 40° was not effected till A.D. 1806. [Sidenote: The Thirst for New Territories] The desire for new territory, for the propagation of religion, and, above all, for the precious metals, were the chief motives which prompted the voyages of the fifteenth and sixteenth centuries. These motives have remained operative; and to them has been added in more recent times the spirit of pure adventure and the interest in science, together with, increasing measure, the effort to secure trade. But the extension of trade followed slowly in the wake of discovery. China and Japan remained almost closed. The policy of Spain sought to restrict her American waters to her own ships, and the commerce they carried was scanty. Communication remained slow and dangerous across the oceans till the introduction of steam vessels (1825-1830). [Illustration: The Hereford Map: about 1307 Note Paradise at the top, and Jerusalem in the centre The Fra Mauro Map: about 1457 Babylon is shown in the centre of the map The World as Known on the Eve of Discovery of America (Drawn by Martin Behaim in 1492) The World as known in 150 A.D. From a map by Ptolemy, who appears to have had knowledge of the sources of the Nile THE FIRST MAPS: SOME EARLY GEOGRAPHERS’ IDEAS OF THE WORLD] [Illustration: THE MODERN REPRESENTATION OF THE WORLD: SHOWN ON THREE DIFFERENT PROJECTIONS In each case the British Empire is shaded ] [Sidenote: Round the World in 40 Days!] Land transport, though it had steadily increased in Europe, remained costly as well as slow till the era of railway construction began in 1829. The application of steam as a motive power and of electricity as a means of communicating thought has been by far the greatest factor in this long process of reducing the dimensions of the world, which dates back as far as the domestication of beasts of burden, and the invention, first of paddles and oars, and then of sails. The North American Continent can now be crossed in five days, the South American (from Valparaiso to Buenos Ayres) in under two, the Transandine tunnel having now been pierced. The Continent which stretches from the Baltic to the North Pacific can now be traversed in twelve days. By means of the Trans-Siberian line and its steamship connection with the ports of Japan, it is now possible to go round the globe in less than fifty days. Indeed, the journey has recently been done in forty days. Nor is this acceleration of transit more remarkable than its practical immunity, as compared with earlier times, not only from the dangers for which Nature is answerable, but from those also which man formerly interposed. The increase of trade which has followed in the track first of discovery and latterly (with immensely larger volume) of the improvement of means of transport, has been accompanied not only by the seizure of transoceanic territories by the greater civilised States, but also by an outflow of population from those States into the more backward or more thinly-peopled parts of the earth. Sometimes, as in the case of North America, Siberia, and Australia, the emigrants extinguish or absorb the aboriginal population. [Sidenote: Europeanisation of the World] Sometimes, as in the case of India, Africa, and some parts of South America, they neither extinguish nor blend with the previous inhabitants, but rule them and spread what is called civilisation among them--this civilisation consisting chiefly in a knowledge of the mechanical arts and of deathful weapons accompanied by the destruction, more or less gradual, of their pre-existing beliefs and usages. Sometimes, again, as in the case of China, and to some extent also of the Mussulman East, though political dominion is not established, the process of substituting a new civilisation for the old one goes on despite the occasional efforts of the backward people to resist the process. The broad result is everywhere similar. The modern European type of civilisation is being diffused over the whole earth, superseding, or essentially modifying, the older local types. Thus, in a still more important sense than even that of communications, the world is contracted and becomes far more one than it has ever been before. The European who speaks three or four languages can travel over nearly all of it, and he can find on most of its habitable coasts, and in many parts of the lately-discovered interior, the appliances which are to him necessaries of life. The world is, in fact, becoming an enlarged Europe, so far as the externals of life and the material side of civilisation are concerned. The dissociative forces of Nature have been overcome. [Sidenote: Triumph of Natural Science] Putting together the two processes, the process in time and the process in space, which we have been reviewing, it will be seen that the main line of the development of mankind may be described as the transmission and the expansion of culture--that is to say, of knowledge and intellectual capacity. The stock of knowledge available for use and enjoyment has been steadily increased, and what each people accumulated has been made available for all. With this there has come assimilation, the destruction of weaker types of civilisation, the modification by constant interaction of the stronger types, the creation of a common type tending to absorb all the rest. Assimilation has been most complete in the sphere ruled by natural science--that is to say, in the material sphere, less complete in that ruled by the human sciences (including the sphere of political and social institutions), still less complete in the sphere of religious, moral, and social ideas, and as respects the products of literature and art. Or, in other words, where certainty of knowledge is attainable and utility in practice is incontestable, the process of assimilation has moved fastest and furthest. [Sidenote: Nature & the Unity of Mankind] The process has been a long one, for its beginnings reach back beyond our historical knowledge. So far as it lies within the range of history, it falls into two periods, the earlier of which supplies an instructive illustration of the later one which we know better. The effort which Nature--that is to say, the natural tendencies of man as a social being--has been making towards the unification of mankind during the last few centuries, is her second great effort. The first was in progress from the time when the most ancient records begin down to the sixth and seventh centuries of the Christian era. [Illustration: THE FIRST TRAVELLER ROUND THE GLOBE The great exploit of Ferdinand Magellan, who circumnavigated the globe in 1519-1520, ranks among the events of world importance, and was the culminating achievement of the greatest period of discovery in the world’s history. ] Greek civilisation, which itself had drawn much from Egypt, as well as from Assyria, Phœnicia, and the peoples of Asia Minor, permeated the minds and institutions (except the legal institutions), of the Mediterranean and West European countries, and was propagated by the governing energy of the Romans. In its Romanised form it transformed or absorbed and superseded the less advanced civilisations of all those countries, creating one new type for the whole Roman world. With some local diversities, that type prevailed from the Northumbrian Wall of Hadrian to the Caucasus and the deserts of Arabia. The still independent races on the northern frontier of the Empire received a tincture of it, and would doubtless have been more deeply imbued had the Roman Empire stood longer. Christianity, becoming dominant at a time when the Empire was already tottering, gave a new sense of unity to all whom the Greco-Roman type had formed, extended the influence of that type still further, and enabled much that belonged to it (especially its religious, its legal, and its literary elements) to survive the political dominion of the Emperors and to perpetuate itself among practically independent States which were springing up. The authority of Papal Rome helped to carry this sense of unity among civilised men through a period of ignorance, confusion, and semi-barbarism which might otherwise have extinguished it. Nevertheless, we may say, broadly speaking, that the first effort towards the establishment of a common type of civilisation was, if not closed, yet arrested by the dissolution of the Roman Empire in the West. Close thereupon came the rise of Islam, tearing away the Eastern provinces, and creating a rival type of civilisation--though a type largely influenced by the Greco-Roman--which held its ground for some centuries, and has only recently shown that it is destined to vanish. [Sidenote: Conquest and Civilisation] The beginnings of the second effort toward the unification of civilised mankind may be observed as far back as the eleventh and twelfth centuries. Its effective and decisive action may, however, be assigned to the fifteenth, when the spread of literary and philosophic culture, and the swift extension of maritime discovery, ushered in the modern phase wherein we have marked its irresistible advance. This phase differs from the earlier one both in its range--for it embraces the whole earth and not merely the Mediterranean lands--and in its basis, for it rests not so much upon conquest and religion as upon scientific knowledge, formative ideas, and commerce. Yet even here a parallelism may be noted between the ancient and the modern phase. Knowledge and ideas had brought about a marked assimilation of various parts of the ancient world to each other before Roman conquest completed the work, and what conquest did was done chiefly among the ruder races. So now, while it is knowledge and ideas that have worked for the creation of a common type among the peoples of European stock, conquest has been a potent means of spreading this type in the outlying countries and among the more backward races whose territories the European nations have seized. [Illustration: THE EUROPEANISATION OF THE WORLD European civilisation is being diffused all over the earth, superseding or essentially modifying the older local types. The solid black portions of this map represent territory under Anglo-Saxon control; the shaded parts are under other European control, and the dotted parts under Asiatic and African control. ] [Sidenote: Language a Unifying Influence] The diffusion of a few forms of speech has played a great part in both phases. Greek was spoken over the eastern half of the Roman world in the second century A.D., though not to the extinction of such tongues as Syriac and Egyptian. Latin was similarly spoken over the western half, though not to the extinction of the tongues we now call Basque and Breton and Welsh; and Latin continued to be the language of religion, of law, of philosophy, and of serious prose literature in general till the sixteenth century. So now, several of the leading European tongues are spoken far beyond the limits of their birthplace, and their wide range has become a powerful influence in diffusing European culture. German, English, Russian, Spanish, and French are available for the purposes of commerce, and for those who read books over nineteen-twentieths of the earth’s surface. The languages of the smaller non-European peoples are disappearing in those places where they have to compete with these greater European tongues, except in so far as they are a medium of domestic intercourse. Arabic, Chinese, and in less degree Persian are the only non-European languages which retain a world importance. English, German, and Spanish are pre-eminently the three leading commercial languages. They gain ground on the rest, and it is English that gains ground most swiftly. The German merchant is no doubt even more ubiquitous (if the expression be permitted) than is the English; but the German more frequently speaks English than the Englishman or American speaks German. [Sidenote: Linking the Nations Together] It has already been observed that assimilation has advanced least in the sphere of institutions, ideas, and literature. The question might, indeed, be raised whether the types of thought, of national character, and of literary activity represented by the five or six leading nations are not rather tending to become more accentuated. The self-consciousness of each nation, taking the form of pride or vanity, leads it to exalt its own type and to dwell with satisfaction on whatever differentiates it from other types. Nevertheless there are influences at work in the domain of practice as well as of thought, which, in creating a common body of opinion and a sense of common interest among large classes belonging to these leading nations, tend to link the nations themselves together. Religious sympathy, or a common attachment to certain doctrines, such as, for instance, those of Collectivism, works in this direction among the masses, as the love of science or of art does among sections of the more educated class. As regards the peoples not of European stock, who are, broadly speaking, the more backward, it is not yet possible to say what will be the influence of the European type of culture upon their intellectual development. The material side of their civilisation will after a time conform to the European type, though, perhaps, to forms that are not the most progressive; and even such faiths as Buddhism and Islam may lose their hold on those who come most into contact with Europeans. But whether these peoples will produce any new types of thought or art under the stimulus of Europe, as the Teutons and Slavs did after they had been for centuries in contact with the relics of Greco-Roman culture, or whether they will be overborne by and merely imitate and reproduce what Europeans teach them--this is a question for conjecture only, since the data for predictions are wanting. It is a question of special interest as regards the Japanese, the one non-European race which, having an old civilisation of its own, highly developed on the artistic side, has shown an amazing aptitude for appropriating European institutions and ideas. Already a Japanese physiologist has taken high rank among men of science by being one of the discoverers of the bacillus of the Oriental plague. DOES HISTORY MAKE FOR PROGRESS? One of the questions which both the writers and the readers of a History of the World must frequently ask themselves is whether the course of history establishes a general law of progress. Some thinkers have gone so far as to say that this must be the moral of history regarded as a whole, and a few have even suggested that without the recognition of such a principle and of a sort of general guidance of human affairs towards this goal, history would be unintelligible, and the doings of mankind would seem little better than the sport of chance. [Sidenote: What is the Test of Progress?] [Sidenote: What Mankind has Achieved] Whatever may be thought of these propositions as matters of theory, the doctrine of a general and steady law of progress is one to which no historian ought to commit himself. His business is to set forth and explain the facts exactly as they are; and if he writes in the light of a theory he is pretty certain to be unconsciously seduced into giving undue prominence to those facts which make for it. Moreover, the question is in itself a far more complex one than the simple word “progress” at first sight conveys. What is the test of progress? In what form of human advance is it to be deemed to consist? Which of these forms is of the highest value? There can be no doubt of the advance made by man in certain directions. There may be great doubt as to his advance in other directions. There may possibly be no advance but even retrogression, or at least signs of an approaching retrogression, in some few directions. The view to be taken of the relative importance of these lines of movement is a matter not so much for the historian as for the philosopher, and its discussion would carry us away into fields of thought not fitted for a book like the present. Although, therefore, it is true that one chief interest of history resides in its capacity for throwing light on this question, all that need here be said may be expressed as follows: There has been a marvellous advance in man’s knowledge of the laws of Nature and of his consequent mastery over Nature. There has been therewith a great increase in population, and, on the whole, in the physical vigour of the average individual man. There has been, as a further consequence, an immense increase in the material comfort and well-being of the bulk of mankind, so that to most men necessaries have become easier of attainment, and many things which were once luxuries have become necessaries. Against this is to be set the fact that some of the natural resources of the world are being rapidly exhausted. This would at one time have excited alarm; but scientific discoveries have so greatly extended man’s capacity to utilise other sources of natural energy, that people are disposed to assume that the loss of the resources aforesaid will be compensated by further discoveries. [Sidenote: The Gain and the Loss] As to progress other than material--that is to say, progress in intellectual capacity, in taste, in the power of enjoyment, in virtue, and generally in what is called happiness--every man’s view must depend on the ideal which he sets before himself of what constitutes happiness, and of the relative importance to happiness of the ethical and the non-ethical elements which enter into the conception. Until there is more agreement than now exists or has ever existed on these points, there is no use in trying to form conclusions regarding the progress man has made. Moreover, it is admitted that nearly every gain man makes is accompanied by some corresponding loss--perhaps a slight loss, yet a loss. When we attempt to estimate the comparative importance of these gains and losses, questions of great difficulty, both ethical and non-ethical, emerge; and in many cases our experience is not yet sufficient to determine the quantum of loss. There is room both for the optimist and for the pessimist, and in arguing such questions nearly everybody becomes an optimist or a pessimist. The historian has no business to be either. There is another temptation besides that of delivering his opinion on these high matters, of which the historian does well to be aware--I mean the temptation to prophesy. The study of history as a whole, more inevitably than that of the history of any particular country or people, suggests forecasts of the future, because the broader the field which we survey the more do we learn to appreciate the great and wide-working forces that are guiding mankind, and the more therefore are we led to speculate on the results which these forces, some of them likely to be permanent, will tend to bring about. [Sidenote: Modern Mastery of Nature] This temptation can seldom have been stronger than it is now, when we see all mankind brought into closer relations than ever before, and more obviously dominated by forces which are essentially the same, though varying in their form. Yet it will appear, when the problem is closely examined, that the very novelty of the present situation of the world--the fact that our mastery of Nature has been so rapidly extended within the last century, and that the phenomena of the subjugation of the earth by Europeans and of the ubiquitous contact of the advanced and the backward races are so unexampled in respect of the area they cover--that all predictions must be uttered with the greatest caution, and due allowance made for elements which may disturb even the most careful calculations. It may, indeed, be doubted whether any predictions of a definitely positive kind--predictions that such and such things will happen--can be safely made, save the obvious ones which are based on the assumption that existing natural conditions remain for some time operative. [Sidenote: A Glimpse into the Future] Taking this assumption to be a legitimate one, it maybe predicted that population will continue to increase, at least till the now waste but habitable parts of the earth have been turned to account; that races, except where there is a marked colour line, will continue to become intermingled; that the small and weak races, and especially the lower set of savages, will be absorbed or die out; that fewer and fewer languages will be spoken; that communications will become even swifter, easier, and cheaper than they are at present; and that commerce and wealth will continue to grow, subject, perhaps, to occasional checks from political disturbance. There are also some negative predictions on which one may venture, and with a little more confidence. No new race can appear, except possibly from a fusion of two or more existing races, or from the differentiation of a branch of an existing race under new conditions, as the Americans have been to some slight extent differentiated from the English, and the Brazilians from the Portuguese (there having been in the latter case a certain admixture of negro blood), and as the Siberians of the future may be a different sort of Russians. Neither is any new language likely to appear, except, mere trade jargons (like Chinook or pigeon English), because the existing languages of the great peoples are firmly established, and the process of change within each of these languages has, owing to the abundance of printed matter, become now extremely slow. Conditions can hardly be imagined under which such a phenomenon as the development of the Romance languages out of Latin, or of Danish and Swedish out of the common Northern tongue of the eleventh century, could recur. [Illustration: THE PEOPLES OF THE WORLD AT PEACE From the statuary groups on the Albert Memorial. ] It may seem natural to add the further prediction that the great States and the great religions will continue to grow and to absorb the small ones. But when we touch topics into which human opinion or emotion enters, we touch a new kind of matter, where the influences now at work may be too much affected by new influences to permit of any forecast. Conditions might conceivably come into action which would split up some or most of the present great States, and bring the world back to an age of small political communities. So, too, though the lower forms of paganism are fast vanishing, and the four or five great religions are extending their sway, it is conceivable that new prophets may arise, founding new faiths, or that the existing religions may be split up into new sects widely diverse from one another. Even the supremacy of the European races, well assured as it now appears, may be reduced by a variety of causes, physiological or moral, when some centuries have passed. [Illustration: THE PEOPLES OF THE WORLD AT PEACE From the statuary groups on the Albert Memorial. ] Whoever examines the predictions made by the most observant and profound thinkers of the past will see reason to distrust almost all the predictions, especially those of a positive order, which shape themselves in our minds to-day. JAMES BRYCE [Illustration: SUMMARY OF WORLD HISTORY WITH A CHRONOLOGY OF TEN THOUSAND YEARS By Arthur D. Innes, M.A.] Within the memory of living men, the most advanced peoples of the world believed that the world itself had been created not 6,000 years ago. We have all learned now that the globe itself, that life--and long later mankind--came into being thousands, hundreds of thousands--it may be millions--of years ago. How long precisely, none can tell. What we do know with certainty is that before the continents finally emerged in their present shape there was an Ice Age, immediately preceded by what is called the Drift Age, and that as early as the Drift Age man, the maker of implements, lived, and did battle with the cave bear and other monsters. Where man first came into being, how he spread over the globe, how the great races acquired their characteristics, we can only conjecture. [Sidenote: The Birth of the Nations] Wherever and whenever man appeared, the earliest traces show him to have been a sociable animal living in communities. The earliest unmistakable traces of civilisation, order, polity, are found in the basins of the Nile and the Euphrates, dating probably as far back as ten thousand years ago. The people who built the Pyramids had already advanced far in the knowledge which gives man the mastery over Nature; and the Pyramids were built certainly 3,000, and probably nearer 5,000, years before the Christian era. And while those pristine civilisations rose and fell in Egypt, civilisations were rising and passing away in Mesopotamia also. In the fourth millennium there appears first a people with new characteristics--the Semitic race, gradually dominating the Mesopotamian civilisation, spreading westward in successive waves to the Mediterranean, surging into Egypt and out again; creating the Empires of Babylonia and of Assyria, and the Phœnician and Canaanite nations. And while the Semite Empires rose and fell, and Egypt held upon her ancient way, still mightier nations were coming to birth. The great Aryan or Indo-European migrations began, the Celt, the Latin, and the Hellene rolling westward by the Euxine and the Northern Mediterranean; while another group passed southward, to the East of the Semites, spreading the Aryan conquest over the greater part of the Indian peninsula. [Sidenote: Conflicts of Ancient Peoples] Of the doings of the great Semitic Powers in the second millennium B.C. we have some knowledge from the Hebrew records; and year by year fresh light is thrown on those records by inscriptions and tablets newly discovered or newly deciphered, Egyptian, Assyrian, or Hittite. Of the Hittite or early Syrian dominion we know little enough, except that it successfully defied the invading armies of Assyrian kings and Egyptian Pharaohs. Before 1500 the Semite conquerors of Egypt, the Hyksos, were driven out--an event associated by some authorities with the Hebrew Exodus. From this time the ebb and flow of Egyptian and Assyrian dynasties are more definitely recorded. In the closing centuries the prosperity of Tyre and Sidon reached its height, and the theocratic Hebrew nationality formed a kingdom. We become aware of Hellenic or kindred Powers in Asia Minor, at Troy, in Crete, at Mycenæ; of Achæans and Danaans in Egypt. [Sidenote: The First Formation of States] Before another five hundred years had passed, throughout the coasts and islands of the Ægean Sea, Æolians, Ionians, Dorians established themselves in cities, and every city rapidly grew into a highly-organised State. Over the Mediterranean, to Southern Italy, to Sicily, to Marseilles, the new Greek civilisation carried its commerce and its culture. In Italy the Latin races were in like manner forming themselves into city-states, developing conceptions of Government undreamed of by Oriental minds. Rome was founded, and acquired a leadership. Throughout the Hellenic and the Latin world the idea of civic freedom took root; the primitive monarchical systems disappeared, and, through revolutions and temporary despotisms, sometimes peaceful and sometimes violent, the States took on for the most part a Republican form. +--------------------------------------------------------------------+ \| TIME-TABLE OF THE WORLD: B.C. 8000 to 500 \| \| \| \| This Chronology, prepared as a companion to the Summary of the \| \| World’s History, sets forth in tabular form for ready reference \| \| the events dealt with in the narrative on opposite pages \| +-----+-------------------------------------------------------+------+ \|B.C. \| Early civilisation of the Nile Basin. Egypt before \| B.C. \| \|8000 \| the Pyramids. \| 8000 \| \|7000 +-------------------------------------------------------+ 7000 \| \| \| Asiatic invasion of Egypt \| \| \| \| Pre-Semitic civilisations of the Euphrates Basin. \| \| \| \| Susa founded. \| \| \|6000 +-------------------------------------------------------+ 6000 \| \| \| Invasion of Egypt by dynastic race, 5800. Mena rules \| \| \| \| all Egypt. First dynasty, 5500. \| \| \| \| Babylonian kingdoms of Sumer and Akkad. Ea founds \| \| \| \| Eridu and civilises Babylonia. \| \| \|5000 +-------------------------------------------------------+ 5000 \| \| \| Egypt. The Pyramid builders. Great Pyramid built by \| \| \| \| Khufu (Cheops), 4700. \| \| \| \| Earliest monuments to kings in Babylonia, 4700. \| \| \|4000 +-------------------------------------------------------+ 4000 \| \| \| Egypt invaded from the north. First, or Babylonian, \| \| \| \| Semitic wave in the Euphrates Valley. Rise of \| \| \| \| Babylonian kingdoms. Sargon and Naram-Sin, Semitic \| \| \| \| rulers of Akkad. Middle kingdom of Egypt. Revival \| \| \| \| of art. Twelfth dynasty (3400). \| \| \| \| Gudea’s rule in Babylon. Development of commerce, \| \| \| \| 3300. \| \| \|3000 +-------------------------------------------------------+ 3000 \| \| \| Egypt invaded by the Hyksos, nomadic Semitic \| \| \| \| conquerors, the “Shepherd Kings.” Fifteenth Dynasty \| \| \| \| (2500). Second Hyksos movement (2250). \| \| \| \| Conquest of Babylon by Elamites. Rule of Hammurabi \| \| \| \| (Amraphel of Gen. xiv.), 2129. \| \| \| \| Second, or Canaanite, Semitic wave, extending to the \| \| \| \| Mediterranean. \| \| \| \| First Aryan migration westward over Europe, and \| \| \| \| southward; conquest of Hindostan. \| \| \|2000 +-------------------------------------------------------+ 2000 \| \| \| The Hyksos dominate Egypt. New kingdom. Eighteenth \| \| \| \| dynasty, 1580. \| \| \| \| Expulsion of the Hyksos, about 1560. \| \| \| \| Rise of Assyria. \| \| \| \| The Kassite dynasty in Babylon, about 1750-1130. \| \| \| \| Hittite Empire in Syria. \| \| \| \| Latin and Hellenic entry into Europe and Asia Minor. \| \| \| \| Third (Aramæan) Semitic wave, dominating W. Asia, but \| \| \| \| absorbed in existing states. \| \| \|1500 +-------------------------------------------------------+ 1500 \| \| \| FAR EAST: Beginning of definite Chinese history, with \| \| \| \| the Chau dynasty. \| \| \| \| EGYPT: Nineteenth dynasty, Sethos and the Ramesides; \| \| \| \| struggle with Hittite Empire. \| \| \| \| WESTERN ASIA: Burnaburiash, 1380. Pashe dynasty in \| \| \| \| Babylon, 1130-1000. \| \| \| \| Period of Phœnician prosperity. \| \| \| \| Rise of the United Kingdom of the Hebrews. \| \| \| \| Crete, Troy, and Mycenæ. The Ionic and Doric \| \| \| \| migrations. \| \| \|1000 +-------------------------------------------------------+ 1000 \| \| \| WESTERN ASIA: The Hebrew kingdom divided into Judah \| \| \| \| and Israel or Samaria. \| \| \| \| Rise of Aramæan kingdom of Syria. Chaldean \| \| \| \| domination in Babylon. \| \| \| \| Assyrian Middle Empire. \| \| \| \| EGYPT: Twenty-second dynasty (“Shishak” king of \| \| \| \| Egypt). \| \| \| 900 +-------------------------------------------------------+ 900 \| \| \| EUROPE: Early monarchical governments replaced \| \| \| \| usually by aristocracies. \| \| \| \| Probable period of the Homeric poems. \| \| \| \| WESTERN ASIA: Successful resistance of Syria to \| \| \| \| Assyria. \| \| \| \| Appearance of the (Aryan) Medes in the East. \| \| \| \| AFRICA: Founding of Carthage. \| \| \| 800 +-------------------------------------------------------+ 800 \| \| \| EGYPT: Domination of Ethiopians or Cushites. \| \| \| \| WESTERN ASIA: Assyrian New Empire; conquest of Syria, \| \| \| \| Samaria, and Babylon. \| \| \| \| Lydian and Phrygian kingdoms in Asia Minor. \| \| \| \| EUROPE: Development of city states in Greece and \| \| \| \| Italy. Lycurgan legislation of Sparta, about 800. \| \| \| \| Rome founded as a monarchy, 753. \| \| \| \| Spread of Greek colonies along Mediterranean \| \| \| \| coasts and islands. \| \| \| 700 +-------------------------------------------------------+ 700 \| \| \| WESTERN ASIA: Extension of Lydian kingdom in Asia \| \| \| \| Minor 687-546. \| \| \| \| Irruption of Cimmerians from the North. \| \| \| \| Repulse of Sennacherib before Jerusalem. Decline of \| \| \| \| Assyria. \| \| \| \| EGYPT: Invasion by Esarhaddon. Expulsion of Cushites. \| \| \| \| The Saitic dynasty. \| \| \| \| EUROPE: Between 700 and 500, sporadic displacement of \| \| \| \| aristocracies by “tyrannies,” followed either by an \| \| \| \| oligarchical restoration or by democracies. \| \| \| \| Rome becomes head of the League of Latin cities. \| \| \| \| FAR EAST: Japanese history begins. \| \| \| 600 +-------------------------------------------------------+ 600 \| \| \| WESTERN ASIA: Narbonaid, King of Babylon (556-538). \| \| \| \| Overthrow of Assyrian by New Babylonian Empire; the \| \| \| \| Babylonish captivity. \| \| \| \| Rise of Media, of which Cyrus, the Persian, makes \| \| \| \| himself master. \| \| \| \| Persian Empire: Overthrow of Lydia, New Babylonia, \| \| \| \| and Egypt. Aahmes (Amasis), 570-526. \| \| \| \| FAR EAST: Confucius and Lao-Tse in China, and Buddha \| \| \| \| in India. \| \| \| \| EUROPE: Greek states consolidated. Athens: Solon 594. \| \| \| \| Pisistratidæ expelled, 510. \| \| \| \| ROME: Expulsion of the kings, about 510. The \| \| \| \| Commonwealth. Administration aristocratic: Army and \| \| \| 500 \| legislative assembly on basis of land-ownership. \| 500 \| \| B.C.\| Etruscan--pre-Latin--domination in Italy. \| B.C.\| +-------------------------------------------------------------+------+ In the East an Aryan Power overthrew the last of the Assyrian-Babylonian dynasties; but these Persian conquerors became assimilated to the conquered nations. Fundamentally their empire was of the same type as its predecessors. The Persian sway, however, extended not only into Egypt but over the partly Hellenised Asia Minor; and the Ionic revolt, in the first year of the fifth century B.C. brought the spirit of the East and the spirit of the West into fierce collision. The great king hurled his hosts against defiant Hellas; at Marathon and at Salamis, Athens shattered his army and his fleets. Thenceforth, for a thousand years, the West was the aggressor. [Sidenote: Athens and the Greek Immortals] But the rolling back of the “barbarian” tide was not the only glory that fell to Athens; in that same century the little state bore sons whose names stand in the front rank of the immortals for all time: Æschylus and Sophocles, Phidias, Pericles, Socrates, and Plato; in the next half century, Demosthenes; with others almost if not quite, on the same plane. The character of Athens, idealised, no doubt, is epitomised by Thucydides in the speech of Pericles. She was the sum of all that was best and noblest in Hellenism--its love of freedom, of beauty, of energy, of harmony, and its public spirit. Politically, the story of the period which followed Salamis is mainly one of the rivalry between Athens and Sparta; until the rise of Macedon, when King Philip made himself master of all Hellas. [Sidenote: The Coming-up of Alexander] Then, with the beginning of the last quarter of the fourth century, Alexander the Great blazed upon the world, toppled the empires of Western Asia before him, conquered Egypt, and swept over the great mountain-barriers into India, where Buddhism had already begun to displace the ancient Brahmanism of the first Aryans. The Greek influences did not long linger in the far East after the great conqueror’s death. His empire broke up. Asia west of the Euphrates remained, indeed, under the dominion mainly of one Grecian dynasty, the Seleucidæ; Egypt under that of another, the Ptolemies. Yet Alexander’s attempts to blend East and West failed. Orientalism abode, unconquered, ineradicable; Hellenism prevailed almost after the fashion of British domination in India to-day, in the land, but not of it. Meanwhile, the struggle between Aryans and non-Aryans had been running a partly separate course in the West. The Phœnicians of Carthage and the pre-Aryan Etruscans, the dominant power in Italy, made a joint assault on the Greeks of Sicily and the Latins of the mainland at the beginning of the fifth century. They were beaten back, but for a century the struggle continued between Rome and Veii. The great Celtic incursion of the Gauls threatened destruction to Rome, but completed the destruction of Etruria. In the fourth century and the first half of the third century B.C. Rome was chiefly engaged in the double task of achieving supremacy, passing into actual dominion among the Latin states, and of establishing the great Senatorial oligarchy, against whose stubborn resolution the Epirote Pyrrhus hurled himself in vain. Just sixty years after Alexander’s death began the sixty years’ struggle between Rome and Carthage, in the latter years of which the genius of Hannibal was pitted against the grim persistence of the Roman oligarchy. Carthage fell; Rome triumphed, and with her triumph entered on her career of extended conquest. [Sidenote: The Triumph of Rome] The organisation which had ruled the city-state itself not ill, and raised it to an immense pre-eminence, sufficed also to maintain its powers of conquest, but not its political virtue. Rome’s armies subdued the divided and disorganised realms which more or less recognised the over-lordship of Macedon; they made the Ptolemies and the Seleucidæ acknowledge their supremacy; they shattered the new barbarian hordes, which began to pour across the Alpine passes, and the African tribes of Numidia. But the lofty public spirit was gone which had made Rome so great when she was battling for life. Reformers arose, only to prove that there was no power in the constitution strong enough to enforce reform. Victorious generals with their legions behind them began to dictate legislation; Marius and Sulla, democrats or reactionaries, signalised their political successes by slaughtering hecatombs of their opponents. At last, statesmanship and generalship found their supreme incarnation in one person, Julius Cæsar. For many years one of the two foremost men in the Republic, he finally crushed his rival Pompeius and became acknowledged head of the state. Before he could complete the work of reconstruction, Cæsar fell beneath the daggers of Republican enthusiasts; but ere many years had passed his adopted son Octavian triumphed over all rivals, and established the Principate or Empire, the absolute dominion of one ruler over the whole Roman world--although that dominion was still maintained under the Republican forms. +--------------------------------------------------------------------+ \| TIME-TABLE OF THE WORLD: B.C. 500 to 1 \| \| \| \| Collision of East and West. The Glory of Greece. Alexander and \| His Conquests. The Rise of Rome. Overthrow of Carthage and the \| \| Establishment of the Roman Empire \| +-----+--------------------------+-----------------------------+-----+ \| B.C.\| The East and Africa \| Europe \| B.C.\| \| 500 \| GREECE: Revolt of Ionian \| GREECE: Repulse of Persia \| 500 \| \| \| Greeks from Persia, \| at Marathon (490), \| \| \| \| 499. \| Salamis (480) and Plataea \| \| \| \| Liberation from Persia \| (479) and of Carthage by \| \| \| \| of Greek States in \| Syracuse at Himera (480). \| \| \| \| Asia Minor. \| \| \| \| \| \| ROME: Increase of political \| \| \| \| Revolt of Egypt from \| power of Plebeians. \| \| \| \| Persia: re-conquest. \| Tribunes. First Roman \| \| \| \| \| Legal Code (the XII. \| \| \| \| \| Tables). \| \| \| 450 +--------------------------+-----------------------------+ 450 \| \| \| \| GREECE: Age of Pericles, \| \| \| \| \| the great Athenian \| \| \| \| Egypt again independent \| dramatists, and Phidias. \| \| \| \| of Persia. \| Struggle for supremacy \| \| \| \| \| between Athens and \| \| \| \| \| Sparta. \| \| \| \| \| ROME: Decadence of Etruscan \| \| \| \| \| power. \| \| \| \| \| Progress of Plebeians in \| \| \| \| \| obtaining administrative \| \| \| \| \| power. \| \| \| 400 +--------------------------+-----------------------------+ 400 \| \| \| \| GREECE: Socrates and Plato. \| \| \| \| \| Spartan and Theban \| \| \| \| \| supremacies. \| \| \| \| \| ROME: Invasion by the Gauls.\| \| \| \| \| The land question: the \| \| \| \| \| Licinian Laws. \| \| \| \| \| Establishment of new \| \| \| \| \| “Senatorial” oligarchy. \| \| \| \| Revival of Persian \| Extension of Roman \| \| \| \| energy under \| military settlements \| \| \| \| Artaxerxes Ochus. \| or colonies. \| \| \| 350 +--------------------------+-----------------------------+ 350 \| \| \| Overthrow of Persia by \| GREECE: Philip of Macedon. \| \| \| \| Alexander; India \| Demosthenes at Athens. \| \| \| \| invaded. \| Aristotle. \| \| \| \| Partition of Alexander’s \| Conquests of Alexander \| \| \| \| Empire. The Ptolemies \| the Great, 334-322. \| \| \| \| in Egypt, and the \| ROME: Second Roman treaty \| \| \| \| Seleucidæ in Asia. \| with Carthage. \| \| \| \| Friendly relations \| Dissolution of Latin \| \| \| \| between Seleucus and \| League. Supremacy of \| \| \| \| Chandragupta of \| Rome in Italy. Samnite \| \| \| \| Hindostan. \| wars. \| \| \| 300 +--------------------------+-----------------------------+ 300 \| \| \| \| ROME: Legislative power of \| \| \| \| \| Plebeian Comitia. Tributa \| \| \| \| \| established. \| \| \| \| \| Pyrrhus in Italy and \| \| \| \| \| Sicily. \| \| \| \| Contests between Syria \| Treaty between Rome and \| \| \| \| (Seleucidæ) and Egypt \| Egypt. \| \| \| \| (the Ptolemaic dynasty). \| Senatorial supremacy at \| \| \| \| \| Rome. \| \| \| \| \| First Punic War \| \| \| \| \| (264-241). \| \| \| \| \| GREECE: Rise of the Achæan \| \| \| \| \| League. \| \| \| 250 +--------------------------+-----------------------------+ 250 \| \| \| Asoka, king of Maghada \| Carthaginian power \| \| \| \| (Hindostan), Buddhist. \| established in Spain. \| \| \| \| Extension of the Seleucid\| ROME: Second Punic War, \| \| \| \| dominion under \| 218-201. Hannibal in \| \| \| \| Antiochus the Great. \| Italy, 218-203. Scipio \| \| \| \| Rise of the Parthian \| in Spain, 211-206. \| \| \| \| dominion of the \| Zama, 202. \| \| \| \| Arsacidæ. \| Extension of Roman dominion \| \| \| \| Fall of Carthage, 202. \| over Spain and North \| \| \| \| \| Africa. \| \| \| 200 +--------------------------+-----------------------------+ 200 \| \| \| Wars between Parthia and \| Organisation of provinces \| \| \| \| the Seleucidæ. \| subject to the Imperial \| \| \| \| \| Republic. \| \| \| \| Maccabean revolt of \| History of Europe merges in \| \| \| \| Judæa. \| that of ROME. \| \| \| \| \| Collision of Rome with (1) \| \| \| \| Antiochus Epiphanes \| Macedon; (2) the Syrian \| \| \| \| conquers Egypt, but \| kingdom of the Seleucidæ. \| \| \| \| retires. \| \| \| \| \| \| Macedon becomes a Roman \| \| \| \| Egypt and Syria become \| province. \| \| \| \| Roman protectorates. \| Rome assumes protectorate \| \| \| \| \| of Egypt and Syria. \| \| \| 150 +--------------------------+-----------------------------+ 150 \| \| \| \| Third Punic War, and \| \| \| \| Nabatæan State in Arabia.\| destruction of Carthage, \| \| \| \| \| 146. \| \| \| \| \| Greek States absorbed into \| \| \| \| A Tartar kingdom \| province of Macedonia. \| \| \| \| established in east \| Development of political \| \| \| \| of Parthia. \| power of (1) demagogues; \| \| \| \| \| (2) soldiers. \| \| \| \| \| The Gracchi, 133-121. \| \| \| \| Jugurthan War in Africa. \| Conquest of South Gaul: \| \| \| \| \| defeat of Teutones and \| \| \| \| \| Cimbri by Marius. \| \| \| 100 +--------------------------+-----------------------------+ 100 \| \| \| \| Social war. Marius and \| \| \| \| Mithradatic wars, 88-63. \| Sulla. The Proscriptions. \| \| \| \| \| The Sullan Constitution, 81.\| \| \| \| The East, to the \| Pompey. Rise of Julius \| \| \| \| Euphrates, brought \| Cæsar. \| \| \| \| under Roman dominion. \| The East brought under \| \| \| \| \| Roman dominion. \| \| \| \| Judæa: fall of the \| Cæsar conquers Gaul; \| \| \| \| Maccabees. \| lands in Britain. \| \| \| 50 +--------------------------+-----------------------------+ 50 \| \| \| Scythian or Tartar \| Overthrow of Pompey: Cæsar \| \| \| \| incursion into India, \| virtual emperor. \| \| \| \| and admixture with \| Murder of Cæsar, 44. \| \| \| \| Punjab races. \| Rivalry of Antony and \| \| Octavian, 43-30. \| \| \| \| \| The Principate, or Empire, \| \| \| \| Egypt becomes a Roman \| established under Augustus\| \| \| \| province, 30. \| (Octavian) in virtue of \| \| \| \| \| the Imperium Proconsulare \| \| \| \| \| (27) and Tribunicia \| \| \| \| \| Potestas (23). The Empire \| \| \| 1 \| \| organised. \| 1 \| \| B.C.\| \| Cicero, Virgil Livy, Horace.\| B.C.\| +-----+--------------------------+-----------------------------+-----+ [Sidenote: The Birth of Christ] A tremendous event in itself, the reign of Augustus also witnessed one which has had a great influence on the history of the world--the birth of Christ. His ministry, to which perhaps the term event should be applied, was during the reign of the second Emperor, Tiberius. The new faith born on the soil of Judæa was to modify profoundly all the ideals, social and political as well as theological and personal, of the entire Western world; but for many years its adherents remained nothing more than a persecuted yet steadily growing sect; suspected and hated as anarchists rather than as misbelievers, in a world where the rankest and wildest superstitions lived side by side with a general intellectual scepticism. For four centuries the Imperial city ruled over nearly the whole known world. Beyond the Euphrates on the east, beyond the Rhine and the Danube, she could maintain no permanent footing; within her own borders it seemed as though her sway became a part of the natural order--so much so that when her power had passed away her very conquerors did her homage and took upon themselves titles as her officers. [Sidenote: Rome in her Decline] But the overthrow was yet a long way off. The reconstruction organised by Augustus and his Ministers was developed by able rulers--Tiberius, Trajan, Hadrian, the Antonines--during some two hundred years, in spite of intervals when a murderous tyranny or a feeble incompetence occupied the throne of the Cæsars. From the Pillars of Hercules to the river of Mesopotamia, northward as far as Britain, southward to the deserts of Africa, Roman civilisation, Roman law and justice, Roman military discipline, and Roman roads maintained the Roman peace. [Sidenote: Fall of Rome and Rise of Goths] Then came an era when the Imperial purple became the prize of successful generals acclaimed by their legions; and the frontier armies, themselves largely formed out of Teutonic or other semi-“barbarian” tribes, found themselves face to face with new barbarian hordes which for another century and a half they held in check. But the tremendous external pressure on frontiers so vast made it imperative that the Government should be somewhat decentralised. At the end of the third century Diocletian parted the empire into four great divisions. The new system could not endure; Constantine the Great again became sole emperor. Under him Christianity was at length adopted as the state religion; the Church herself became a fundamental factor in the political system; and the political centre of gravity was transferred from Rome to Byzantium. [Sidenote: Beginning of Byzantium] Again the empire was partitioned, and then, for a brief while before the end of the fourth century, united again under Theodosius. But the end was at hand. For a few years the great general Stilicho held the Teutonic Goths at bay in Italy, while Vandals and Sueves poured through Gaul into Spain. Then, early in the fifth century, Stilicho died. Alaric led his conquering hordes to the gates of Rome, and sacked the Eternal City. His successor, Ataulf, took his Goths away, to drive the Vandals out of Spain into Africa, and set up a great western kingdom on their own account. But after the Goths, fresh barbarians swarmed in--Tartar Huns under Attila, who wrought huge devastation and then vanished for ever; then fresh Teutonic armies, which took possession of Italy, though in the East the Empire still held its own. And in Gaul the (German) Franks under their king, Clovis (Chlodwig, Ludwig), established the dominion which was to give its name to France when the Frankish element had almost passed out of the country. Far-away Britain had already been abandoned, and was falling a prey to the Saxons and the Angles, the “English” who were driving the earlier Celtic inhabitants before them into the mountain fastnesses of the west and north. Again, in the East, in the sixth century, the empire centred at Byzantium asserted its power. Justinian is memorable for that great codification of Roman Law on which the legal systems of half the jurists in Europe have been based. His reign is famous also for the exploits of his brilliant general, Belisarius, who destroyed the Vandal kingdom in Africa, restored the Imperial rule in Italy, and recovered provinces in Asia which had been in danger of falling into the grip of the now aggressive rulers of Persia. But in the West, the success was only temporary. Under pressure of Tartar or Slavonic hosts from the East, a fresh Teutonic swarm, the Lombards, entered Italy and mastered the North. The significance of Rome now lay in the supremacy of her pontificate, unacknowledged in the East. +--------------------------------------------------------------------+ \| TIME-TABLE OF THE WORLD: A.D. 1 to 500 \| \| \| \| Organisation of the Roman Empire. The Rise of Christianity. \| \| Partition of the Empire. The Barbarian Invasion and Fall of the \| \| Western Empire. Rise of the Franks \| +-----+--------------------------+-----------------------------+-----+ \|A.D. \| The East and Africa \| Europe \|A.D. \| \| 1 \| \| Beginning of the Christian \| 1 \| \| \| \| Era. \| \| \| \| \| Imperial system completed \| \| \| \| \| under Tiberius. \| \| \| \| \| Rhine, Danube, and Euphrates\| \| \| \| \| form frontiers of the \| \| \| \| \| Empire. \| \| \| \| \| Caligula and Claudius \| \| \| \| \| emperors. \| \| \| \| \| BRITAIN: Roman occupation. \| \| \| \| \| Spread of Christianity. \| \| \| 50 +--------------------------+-----------------------------+ 50 \| \| \| \| Nero emperor: Galba, Otho, \| \| \| \| \| Vitellius. \| \| \| \| Destruction of Jerusalem \| Vespasian: the “Flavian” \| \| \| \| by Titus, 70. \| emperors. \| \| \| \| \| Nerva chosen by Senate in \| \| \| \| \| succession to Domitian. \| \| \| \| \| The “Five good Emperors,” \| \| \| \| \| 96-180. \| \| \| \| \| Succession of Trajan, 98. \| \| \| 100 +--------------------------+-----------------------------+ 100 \| \| \| Arabia designated as a \| Trajan’s campaigns in Dacia.\| \| \| \| Roman province. \| Administration organised \| \| \| \| Trajan’s expedition to \| under Hadrian. \| \| \| \| the Persian Gulf \| Roman law systematised by \| \| \| \| unsuccessful. Eastward \| Salvius Julianus. \| \| \| \| expansion of Rome \| Antoninus Pius. \| \| \| \| checked. \| \| \| \| 150 +--------------------------+-----------------------------+ 150 \| \| \| Establishment of Roman \| Development of Roman \| \| supremacy in Armenia. \| civilisation in Gaul \| \| \| \| \| and Spain. \| \| \| \| \| Campaigns of Marcus Aurelius\| \| \| \| \| in Pannonia. \| \| \| \| \| The legions in Illyria, \| \| \| \| \| largely composed of \| \| \| \| \| “barbarians,” acquire \| \| \| \| \| power. \| \| \| \| \| After Commodus, series of \| \| \| \| \| emperors by military \| \| \| \| \| selection. \| \| \| \| Successful campaigns of \| Severus temporarily assigns \| \| Severus against \| the West to Clodius \| \| \| \| Parthians. \| Albinus. \| \| \| 200 +--------------------------+-----------------------------+ 200 \| \| \| Persian kingdom of the \| Further systematising of \| \| \| \| Sassanides displaces \| Roman law by the _juris \| \| \| \| the Parthian Empire. \| consulti_, Ulpian, etc. \| \| \| \| \| Increasing pressure of \| \| \| \| \| Teutonic tribes on the \| \| \| \| \| frontier. Campaigns of \| \| \| \| \| Maximinus. \| \| \| \| \| Decius emperor: official \| \| \| \| \| persecution of \| \| \| \| \| Christianity. \| \| \| 250 +--------------------------+-----------------------------+ 250 \| \| \| Overthrow of Emperor \| Advance of the Goths and \| \| \| \| Valerian in the East by\| Alemanni checked \| \| \| \| the Persians. \| by Claudius and Aurelian. \| \| \| \| Destruction of Palmyra \| Diocletian emperor. Division\| \| \| \| in the reign of \| of the Empire under a \| \| \| \| Zenobia. \| subordinate “Augustus” and\| \| \| \| \| two subordinate “Cæsars”. \| \| \| 300 +--------------------------+-----------------------------+ 300 \| \| \| Extension of Buddhism \| Last persecution of \| \| \| \| in China. \| Christians under \| \| \| \| \| Diocletian. \| \| \| \| \| Constantine the Great. \| \| \| \| \| Constantinople (New Rome, \| \| \| \| \| Byzantium) is made the \| \| \| \| \| centre of the Empire. \| \| \| \| \| Christianity established as \| \| \| \| \| the State religion \| \| \| \| \| Council of Nicæa. \| \| \| 350 +--------------------------+-----------------------------+ 350 \| \| \| Unsuccessful Roman \| Temporary revival of Paganism\| \| \| \| campaign against \| under Julian the \| \| \| \| Persia. \| Apostate. \| \| \| \| \| Advance of the Goths checked \| \| \| \| \| by Theodosius. \| \| \| \| \| Empire separated into East \| \| \| \| \| and West, 396. \| \| \| \| \| Alaric the Visigoth held in \| \| \| \| \| check in the Western Empire\| \| \| \| \| by Stilicho. \| \| \| \| \| Westward movement of Vandals \| \| \| \| \| through Gaul to Spain. \| \| \| 400 +-------------------------+------------------------------+ 400 \| \| \| \| Sack of Rome by Alaric, after\| \| \| \| \| death of Stilicho. \| \| \| \| \| End of the Roman occupation \| \| \| \| \| of Britain. \| \| \| \| \| The Goths withdraw westwards.\| \| \| \| \| Establishment of the \| \| \| \| \| Visigothic kingdom of \| \| \| \| \| Theoderic in Spain and \| \| \| \| Vandals, expelled from \| Aquitania. \| \| \| \| Spain, established in \| Irruption of the Huns under \| \| \| \| Africa. \| Attila. \| \| \| 450 +-------------------------+------------------------------+ 450 \| \| \| \| BRITAIN: The coming of the \| \| \| \| \| Saxons. \| \| \| \| \| Barbarian “Patricians” set up\| \| \| \| \| and depose Western \| \| \| \| \| Emperors. \| \| \| \| \| Odoacer, “King” in Italy, \| \| \| \| \| recognises supremacy of the\| \| \| \| \| Eastern Emperor Zeno. \| \| \| \| \| Theoderic the Ostrogoth \| \| \| \| \| founds a Teutonic State in \| \| \| \| \| Italy. \| \| \| 500 \| \| Rise of the Franks in Gaul, \| 500 \| \|A.D. \| \| under Clovis. \|A.D. \| +-----+-------------------------+------------------------------+-----+ In Spain, the Gothic supremacy gave promise of an orderly and just government. In the wide realms of the Franks anarchy and bloodshed were almost ceaseless. In neither did the dominant Teutons drive out the older Iberian and Celtic populations, as the English were doing in the open lands of the northern island. In both, the German institutions were developing into that feudal system which was utterly incompatible with the maintenance of a strong central rule, since it enabled a powerful vassal to bid defiance to his nominal suzerain. Throughout the sixth and seventh centuries progress was stayed in ancient Gaul; in Spain it was to be revolutionised by a new invader. [Sidenote: Islam in Being] Eastward, at the end of the sixth century, the Slavonic wave was surging upon the empire’s northern frontier; in Asia, Persia was again forcing her way towards the Mediterranean. Both were checked by the Emperor Heraclius early in the seventh century. But, meantime, a new Power had come into being. Mohammed had arisen. Inspired by the fanatical fervour of Islam, the warriors of Arabia, soon to be known as the Saracens, swept all before them. They did not at first make Europe their objective; the Caliphs carried their conquering arms over Western Asia, into Egypt, and along the southern coasts of the Mediterranean. Then they began to beat against the empire itself. The eighth century had hardly opened when they poured into Spain; dissensions among the Gothic chiefs gave them prompt victory. They swept up to the Pyrenees; but their advance was stayed by Charles Martel, the virtual lord of the Frankish kingdom. On the East their armies assailed Constantinople, but were disastrously repulsed by the Emperor Leo the Isaurian. Now, for the first time, Papal sanction was demanded and obtained for a change of dynasty. The last Merovingian king of the Franks was deposed in favour of Pepin, the son of Charles Martel. He was succeeded by his son, Karl, a German of the Germans, despite the French form of his popular title Charlemagne. [Sidenote: Charlemagne and His Empire] During his long reign the Moors in Spain were driven back beyond the Ebro; the Saxon tribes across the Rhine were forced to submit and to accept Christianity; the Lombard oppressors of Italy were vanquished; and on the Pope’s initiative, Charlemagne himself was acclaimed and crowned at Rome as emperor and successor of the Cæsars. All of the West that remained to Byzantium was Southern Italy. The revived empire came into being on Christmas Day, A.D. 800. The great dominion and the organisation constructed by Charlemagne fell into divisions after his death. The lands east of the Rhine remained German; on the west, the Teutonic forces yielded to the Latinised Celtic spirit. Slowly France and Germany emerged. In England the supremacy among the rival peoples passed from the Angles of Northumbria or of the Midlands to the Saxon house of Wessex. Hungary was held by the Mongolian Avars, presently to be displaced by their Magyar kinsmen; otherwise Eastern Europe, Illyria, as well as the Trans-Danube districts, was being gradually possessed by the Slavonic races. Their westward movement was decisively stayed in the tenth century by Henry the Fowler and Otto the Great, who, for the second time, revived the “Holy Roman Empire” in the West in a form which effectively translated it into the “German Empire.” Meanwhile, the Vikings from the north first ravaged the western coasts, then wrung great provinces from the kings of England, and of “Francia,” preparing for the day when the Norman spirit should set the tone of Western Europe. [Sidenote: Birth of Feudalism in Europe] In the Eastern Mohammedan world the Saracen dominion was passing to Tartar races--to the Seljuk Turks or the Ghaznavid Turks, and later to the Ottomans; the genuine Saracens had seen their greatest days in the times of Harun-al-Raschid, when the Frankish Empire of Charlemagne was being dismembered. Europe in the eleventh century had passed, or was passing, into what is distinctively known as the Feudal Period, or later Middle Ages. Everywhere it became the object of the great rulers to establish a strong central government, and of the Papacy to establish a supremacy over all governments. Feudalism and the Papacy were the rivals of the centralising tendency. +--------------------------------------------------------------------+ \| TIME-TABLE OF THE WORLD: A.D. 500 to 1000 \| \| \| \| Teutonic Races Dominate the West. Rise of Mohammed: extension of \| \| Mohammedan Rule from Cordova to Kabul. Western Empire Revived \| \| by Charlemagne and again by Otto \| +-----+--------------------------+-----------------------------+-----+ \|A.D. \| The East and Africa \| Europe \|A.D. \| \| 500 \| \| Franks predominant on Rhine \| 500 \| \| \| \| and in Gaul. \| \| \| \| \| Justinian emperor at \| \| \| \| \| Constantinople. \| \| \| \| Overthrow of the African \| Roman Law codified in the \| \| \| \| Vandal kingdom by \| Institutes. \| \| \| \| Belisarius, general of \| Overthrow of Gothic kingdom \| \| \| \| Justinian. \| in Italy by Belisarius. \| \| \| \| \| Advance of Saxons (South) \| \| \| \| \| and Angles (East) in \| \| \| \| \| England. \| \| \| 550 +--------------------------+-----------------------------+ 550 \| \| \| Buddhism introduced in \| Lombard conquest of North \| \| \| \| Japan. \| Italy. \| \| \| \| \| Spread of Celtic \| \| \| \| \| Christianity in Britain by\| \| \| \| \| St. Columba. \| \| \| \| Advance of Persia against\| Pontificate of Gregory the \| \| \| \| the Eastern Empire. \| Great. \| \| \| \| \| Latin Christianity \| \| \| \| \| introduced into Kent by \| \| \| \| \| St. Augustine, 597. \| \| \| 600 +--------------------------+-----------------------------+ 600 \| \| \| Overthrow of Persia by \| ENGLAND: Supremacy of \| \| \| \| Emperor Heraclius. \| Northumbria. \| \| \| \| MOHAMMED. The Hegira \| \| \| \| \| (622). \| ITALY: North under Lombard \| \| \| \| \| dominion; South attached \| \| \| \| Conquest of Egypt and \| to the Eastern Empire. \| \| \| \| Syria by the Caliphs \| \| \| \| \| Abu-bekr and Omar. \| Avar dominion in Hungary. \| \| \| \| Conquest of Persia, and \| \| \| \| \| extension of Caliphate \| Slavonic settlement in \| \| \| \| over West Asia. \| Servia. \| \| \| 650 +--------------------------+-----------------------------+ 650 \| \| \| Saracens (Caliphate) \| ENGLAND: Final overthrow of \| \| \| \| attack the Empire in \| Paganism. \| \| \| \| the East and in Africa.\| Triumph of Roman over Celtic\| \| \| \| \| Christianity. \| \| \| \| Rise of the Shiite sect \| FRANKS: Dukes of Austrasia \| \| \| \| of Mohammedans. \| (East Franks) dominate the\| \| \| \| \| Merovingian kings. \| \| \| 700 +--------------------------+-----------------------------+ 700 \| \| \| Revival in India of \| Saracens (or Moors) \| \| \| \| Brahmanism, gradually \| overrun Spain. \| \| \| \| developing into modern \| Saracen advance checked by \| \| \| \| Hinduism. \| Emperor Leo the Isaurian \| \| \| \| \| at Constantinople, and by \| \| \| \| \| Charles Martel at Tours. \| \| \| \| \| Beginning of the \| \| \| \| \| Iconoclastic controversy. \| \| \| \| \| Discussions between Papacy \| \| \| \| \| and Eastern Church. \| \| \| 750 +--------------------------+-----------------------------+ 750 \| \| \| \| ENGLAND: Supremacy of \| \| \| \| \| Mercia. \| \| \| \| Division of the Caliphate\| FRANKS: Fall of the \| \| \| \| into Eastern (Abassid) \| Merovingian dynasty. \| \| \| \| at Bagdad and Western \| Pepin the Short founds the \| \| \| \| (Ommeiad) at Cordova. \| Karling or Carolingian \| \| \| \| \| Dynasty. \| \| \| \| Rise of the Turks in the \| Empress Irene at \| \| \| \| Caliphate armies. \| Constantinople. \| \| \| \| \| FRANKS: Karl the Great \| \| \| \| Harun-al-Raschid Caliph \| (Charlemagne) succeeds \| \| \| \| at Bagdad. \| Pepin as king of the \| \| \| \| \| Franks. He drives the \| \| \| \| \| Moors beyond the Ebro, \| \| \| \| \| conquers the Lombards, and\| \| \| \| \| is crowned as Roman \| \| \| \| \| Emperor by the Pope. \| \| \| \| \| (800). \| \| \| 800 +--------------------------+-----------------------------+ 800 \| \| \| \| Subjugation of the Saxons \| \| \| \| \| by Charlemagne. \| \| \| \| Increasing power of the \| Division of Charlemagne’s \| \| \| \| Western Caliphate. \| dominion among his \| \| \| \| \| grandsons. \| \| \| \| \| ENGLAND: Supremacy of \| \| \| \| \| Wessex under Egbert. \| \| \| \| \| The Danes, or Northmen, \| \| \| \| \| harry the coasts of \| \| \| \| \| Europe. \| \| \| 850 +--------------------------+-----------------------------+ 850 \| \| \| Fatemide Mohammedan \| Carolingian dominion divided\| \| \| \| dynasty established in \| into West (Francia), East \| \| \| \| Egypt. \| (Franconia, Germany), \| \| \| \| Decline of the Abassid \| Central (Burgundy) and \| \| \| \| Caliphs. \| Italy. \| \| \| \| \| Pressure of Slavonic peoples\| \| \| \| \| on East Germany. \| \| \| \| \| ENGLAND: Alfred the Great. \| \| \| \| \| Settlement of the Danes \| \| \| \| \| in the Danelagh. \| \| \| \| \| Organisation of \| \| \| \| \| Government, Law, etc. \| \| \| \| \| Advance of Magyars in \| \| \| \| \| Hungary. \| \| \| \| \| Iceland colonised, 874-950. \| \| \| 900 +--------------------------+-----------------------------+ 900 \| \| \| \| FRANCE: Duchy of Normandy \| \| \| \| \| ceded to Rollo. \| \| \| \| \| NORWAY united under Harold \| \| \| \| \| Haarfager. \| \| \| \| \| ENGLAND: House of Wessex \| \| \| \| \| kings of all England. \| \| \| \| \| GERMANY: Henry the Fowler, \| \| \| \| \| Saxon King of Germany, \| \| \| \| \| and his son Otto the \| \| \| \| \| Great, check the Magyar \| \| \| \| \| advance. \| \| \| \| \| Pressure of Slavs on \| \| \| \| \| Eastern Empire. \| \| \| 950 +--------------------------+-----------------------------+ 950 \| \| \| Recovery of Eastern \| EMPIRE: Otto becomes King \| \| \| \| Provinces from the \| of Italy and Roman \| \| \| \| Saracens by the \| Emperor. The Holy Roman \| \| \| \| Byzantine Empire. \| Empire is from this time \| \| \| \| \| definitely German. \| \| \| \| \| FRANCE: The Capet dynasty \| \| \| \| \| replaces the Carolingian. \| \| \| \| \| Slavs driven back by Eastern\| \| \| \| \| Emperors. Russians \| \| \| \| \| Christianised. Slav \| \| \|1000 \| \| dominion established in \|1000 \| \|A.D. \| \| Poland. \|A.D. \| +-----+--------------------------+-----------------------------+-----+ [Sidenote: England and France] In England, where a Norman dynasty and Norman aristocracy established themselves, the unifying process was astonishingly rapid. The country was comparatively shielded from Papal interposition by distance. A series of vigorous and able monarchs prevented pure feudalism from ever getting developed; it resulted that in the thirteenth century baronage and people made common cause in imposing not feudalism, but constitutional control over the kings. In France, the victory of the crown over feudalism was far slower; the feudatories were too powerful, and among them were the kings of England, as dukes or counts of great territories within France. The Hundred Years’ War was, in fact, not so much a contest for the French crown as a struggle between the French kings and their mightiest vassals. It was not till the English had been finally expelled that Louis XI. was enabled to make the crown supreme in France. There, as in England, the monarchy never submitted to the Papacy; it was so far victorious in that struggle that in the fourteenth century the seat of the Roman pontificate was transferred to Avignon, and the Pontiff himself became literally the creature of France. [Sidenote: Christendom and the Crusades] Spain and Byzantium alike remained for the most part outside the general European current. They were the buffers between Christendom and Islam. In the Spanish Peninsula the Moors were held more or less at bay, but the land was not freed from their dominion till the close of the fifteenth century. Byzantium held the Turks at bay till the middle of the same century; then she fell for ever. Between the eleventh and thirteenth centuries, Christendom carried on against Islam the long contest of the Crusades; but the warriors who took part in those wars neither fought nor organised as though themselves forming an organic body; the Christian hosts in Palestine were mere miscellaneous gatherings, united only in the temporary fits of enthusiasm. The Holy Sepulchre was gained, but within a century it was lost again; the crusading cause was one to which not states, but individuals only, devoted themselves. Conquest would have been possible only if the Crusaders had gone forth prepared to make their own homes in Asia. The East could not be held by garrisons with no abiding interest there. Islam, then, held, and more than held, its own against the West; while during these same centuries it swept east and south through the passes of the Punjab into India, establishing Turk and Afghan kingdoms over most of the great peninsula; though the vast bulk of the population there held to the Hinduism which, born of the earlier Brahmanism, had almost expelled the Buddhist religion, which, however, had established itself permanently in Further India and China. [Sidenote: Empire, Feudalism, & Papacy] The might of Islam could have been overthrown only by a united Christendom, and for that the disintegrating forces were too great. England and, more slowly, France freed themselves from feudalism. But Christendom required one head. If the Papacy had stood by the empire, feudalism might have been broken down, and the emperor have become that head. But the Papacy aimed at supremacy for itself--the spiritual power was at war with the temporal. Anti-imperial factions claimed the support of the Church; the efforts at consolidation of the great Hohenstaufen Emperors, Barbarossa and Frederick II., were unsuccessful. The empire itself became only a congeries of kingdoms and dukedoms, counties, bishoprics, free cities, and leagues of cities, under the Austrian house of Hapsburg; while Rome, mighty from the days of Gregory VII. to Innocent III., lost its prestige in the captivity at Avignon and by the Great Schism which followed. In England Wycliffe’s voice was raised; on the south-east of the empire the Hussite wars raged, premonitory of the Reformation. [Sidenote: End of the Middle Ages] In 1453 Constantinople fell, and the Turk was permanently established in the east of Europe. As a counterstroke, in the west, not forty years later, the Moorish dominion in Spain was wiped out, Spain emerging as a united Christian kingdom. Before the end of the century Columbus and Gama had discovered America, and virtually rediscovered India. Across the ocean a new, almost unlimited field for expansion, for enterprise, for rivalry had been opened to the European peoples. Already in the realms of intellect old forgotten knowledge had been gradually recovered by the Renascence, the revival of learning and letters; with the intellectual expansion and the invention of the printing press paths to new knowledge were being opened. Men were shaking themselves free from the shackles of authority and tradition. Hence, the sixteenth century witnessed that revolt of half Western Christendom from Rome which we call the Reformation; in its essence, though by no means in its form at the first, a revolt against the interposition of any human authority between the individual man and his Maker. With that revolt political and national divisions were inextricably blended, while the whole was complicated by the new conditions of political supremacy created by the New World. +--------------------------------------------------------------------+ \| TIME-TABLE OF THE WORLD: A.D. 1000 to 1500 \| \| \| \| Development of Feudalism. The Rise and Decadence of the Papacy. \| \| The Crusades. Holy Roman Empire. The Organisation of England, \| \| France, and Spain. The Renaissance \| +-----+--------------------------+-----------------------------+-----+ \|A.D. \| The Non-Christian World \| Christendom \|A.D. \| \|1000 \| \| \|1000 \| \| \| Mahmud of Ghazni. \| Scandinavian power: Canute, \| \| \| \| Beginning of \| King of Norway, Sweden, \| \| \| \| Mohammedan invasions \| Denmark, and England. \| \| \| \| of India. \| Franconian line of emperors;\| \| \| \| \| Burgundy reunited to \| \| \| \| \| Empire. \| \| \| \| \| Dynasty of Hugh Capet in \| \| \| \| \| France. \| \| \|1050 +--------------------------+-----------------------------+1050 \| \| \| \| ENGLAND: The Norman \| \| \| \| \| conquest, 1066. \| \| \| \| \| Norman conquests in Sicily \| \| \| \| \| and S. Italy. \| \| \| \| Power of the Seljuk \| Power of the Empire under \| \| \| \| Turkish Dynasty. \| Henry III. \| \| \| \| \| Pontificate of Gregory VII. \| \| \| \| \| (Hildebrand). Beginning \| \| \| \| \| of the struggle between \| \| \| \| \| Papacy and Empire (Henry \| \| \| \| \| IV.) \| \| \| \| \| First Crusade. \| \| \|1100 +--------------------------+-----------------------------+1100 \| \| \| \| Development of Papal power. \| \| \| \| \| ENGLAND: Organisation of \| \| \| \| \| central government under \| \| \| \| \| Henry I. checked under \| \| \| \| \| Stephen. \| \| \| \| \| Norman kingdom of Sicily. \| \| \| \| \| Conrad, first Hohenstaufen \| \| \| \| \| emperor. Beginning of \| \| \| \| \| Guelphs (Papal) and \| \| \| \| \| Ghibellines (Imperial). \| \| \|1150 +--------------------------+-----------------------------+1150 \| \| \| \| The Angevin dominion of \| \| \| \| \| II., comprising half \| \| \| \| \| France. \| \| \| \| Establishment of \| ENGLAND: End of feudal \| \| \| \| Mohammedan (Ghori) \| anarchy. Maximum power of \| \| \| \| dynasty at Delhi. \| Crown. Henry worsted in \| \| \| \| \| the struggle with the \| \| \| \| \| Church. \| \| \| \| Conquests of the Saracens\| Chivalry typified in Richard\| \| \| \| under the Seljuk \| Cœur-de-Lion. \| \| \| \| Saladin. \| Frederick Barbarossa \| \| \| \| \| emperor, 1155-1190. \| \| \| \| Third Crusade \| City development. Lombard \| \| \| \| (Cœur-de-Lion). \| League; and German Free \| \| \| \| \| Cities. \| \| \| \| \| Advance of Moors in Spain. \| \| \|1200 +--------------------------+-----------------------------+1200 \| \| \| Genghis Khan: Tartar \| Highest power of Papacy, \| \| \| \| conquests in Asia and \| under Innocent III. \| \| \| \| irruption into Europe. \| Francis of Assisi: \| \| \| \| Buddhism obsolescent in \| institution of Mendicant \| \| \| \| India. \| Friars. \| \| \| \| \| ENGLAND: Magna Charta; \| \| \| \| \| contest of Crown and \| \| \| \| \| Barons. Loss of Angevin \| \| \| \| \| dominion. \| \| \| \| \| FRANCE: Development of \| \| \| \| \| central power under Louis \| \| \| \| \| VIII. and IX. \| \| \| \| \| Institution of the Teutonic \| \| \| \| \| knights. \| \| \| \| \| Break up of the Eastern \| \| \| \| \| Empire. Venice. \| \| \|1250 +--------------------------+-----------------------------+1250 \| \| \| \| Decadence of Imperial power.\| \| \| \| \| First Habsburg emperor. \| \| \| \| \| End of the Crusading period.\| \| \| \| Rise of the Ottoman \| ITALY: Rise of Florence. \| \| \| \| (Othman) Turks. \| Dante. Giotto. \| \| \| \| Khublai Khan in Eastern \| ENGLAND: Establishment of \| \| \| \| Asia. \| Parliament (Montfort and \| \| \| \| \| Edward I.). Organisation \| \| \| \| \| of the English nation. \| \| \|1300 +--------------------------+-----------------------------+1300 \| \| \| \| The Papacy “in captivity” \| \| \| \| \| at Avignon. \| \| \| \| Mameluke Sultans in \| Independence of Scotland. \| \| \| \| Egypt. \| Independence of Switzerland.\| \| \| \| \| Ottoman Turks establish a \| \| \| \| \| footing in Europe. \| \| \| \| \| ENGLAND AND FRANCE: \| \| \| \| \| Beginning of the 100 \| \| \| \| \| Years’ War. \| \| \|1350 +--------------------------+-----------------------------+1350 \| \| \| Rise of the Ming dynasty \| The Jacquerie in France. \| \| \| \| in China: expulsion of \| The Great Schism: period \| \| \| \| Mongols. \| of dual Papacy. \| \| \| \| \| ENGLAND: Peasant revolt. \| \| \| \| Conquests of Timur the \| Failure of Richard II.’s \| \| \| \| Tartar (Tamerlane) \| attempt at absolutism. \| \| \| \| \| Wycliffe. \| \| \| \| \| Union of Lithuania with \| \| \| \| \| Poland. \| \| \|1400 +--------------------------+-----------------------------+1400 \| \| \| Empires of Mexico and \| End of Great Schism. \| \| \| \| Peru. \| Hussite wars. \| \| \| \| \| English conquest of France, \| \| \| \| \| and subsequent expulsion. \| \| \| \| \| Increasing powers of \| \| \| \| \| Parliament. \| \| \| \| \| Invention of printing press.\| \| \|1450 +--------------------------+-----------------------------+1450 \| \| \| \| Turks capture \| \| \| \| \| Constantinople. \| \| \| \| \| ENGLAND: Wars of the Roses, \| \| \| \| \| 1455-1485. \| \| \| \| \| Maritime greatness of \| \| \| \| \| PORTUGAL. \| \| \| \| \| SPAIN consolidated under \| \| \| \| \| Ferdinand and Isabella. \| \| \| \| Discovery of America by \| FRANCE consolidated under \| \| \| \| Christopher Columbus; \| Louis XI. \| \| \| \| and of Cape route to \| ENGLAND consolidated under \| \| \| \| India by Vasco da Gama.\| Henry VII. Establishment \| \| \| \| \| of absolutism under \| \| \| \| \| constitutional forms. \| \| \|1500 \| \| Revival of learning. \| 1500\| \|A.D. \| \| Humanists. Savonarola. \|A.D. \| +-----+--------------------------+-----------------------------+-----+ [Sidenote: Growth of Modern Nations] The next two centuries, then, saw France, already a consolidated state, develop into the first military Power under the most absolute monarch in Europe--through a stage of prolonged religious strife which ended by establishing the tolerationist Bourbon, Henry IV., on the throne, through the rule of the two great cardinals, Richelieu and Mazarin, to the intolerant autocracy of Louis XIV., with a close aristocracy no longer in opposition to the crown but allied to it. In England the development was on different lines. There we find an absolutist movement, the outcome of the Wars of the Roses. But however autocratic the Tudors were, they held by constitutional forms, and preserved the intense loyalty of their people. On Elizabeth’s death, a century-old matrimonial alliance placed the sceptres of England and Scotland in a single hand. Then, on the theory of Divine right, the Crown attempted to override the constitution; the Civil War gave the power neither to king nor parliament, but to a military dictator. On his death the country reverted to a compromise between Crown and Parliament; the Stuarts, again, with the aid of their cousin, the autocrat of France, attempted to recover absolutism. They were driven from the country, and constitutionalism--in effect, government by an oligarchy of landowners--was decisively established. The religious problem had found a decisively Protestant solution at an early stage; but Anglicanism and Puritanism soon grew mutually intolerant; it was only with the Revolution of 1688 that toleration and constitutionalism definitely triumphed together. [Sidenote: Europe in Development] Meanwhile, in the reign of Elizabeth, England had asserted her intellectual eminence by giving birth to Shakespeare and to Bacon; and had decisively displaced Spain from the rulership of the seas. In the next century her colonisation of North America counterbalanced the Spanish dominion in the south and centre of the Western Hemisphere, though it was not unchallenged by France. In the East a great commercial rivalry had grown up between English, Dutch, and French--a rivalry still to be fought out. [Sidenote: Collision of the Dynasties] In the early years of the sixteenth century matrimonial alliances had joined Spain, the Low Countries, and the empire under a single ruler, a Hapsburg of the (Austrian) Imperial house. The vast dominion was extended by the acquisition of the golden territories of the American continent. The Empire passed to one Hapsburg branch, Spain and her dependencies to another. In the empire, a temporary _modus vivendi_ was established between Roman Catholics and Protestants; but Spain, the colossus which threatened to dominate Europe, was split by the revolt of the Netherlands, and her power shaken to its foundations by the collision with England. In the sixteenth century, Germany was devastated by the religious Thirty Years’ War; Austria emerged only as the chief among a number of German states, and Holland won a naval and commercial position second only to that of England. The Ottoman Turks, still aggressive, were still held in check. In India, a Turkish dynasty known as the Moguls (Mughàls, Mongols) extended its sway from Kabul to the mouth of the Ganges, and almost to Cape Comorin. At the opening of the eighteenth century the aggressive Continental policy of Louis XIV. involved Europe in the “War of the Spanish Succession.” The French king’s armies were shattered by repeated blows at the hands of Marlborough and Eugene, but he finally obtained his primary object, the recognition of his grandson as king of Spain. The threat of a Hapsburg domination passed into the threat of a Bourbon domination. In the east of Europe a final limit was set to the Ottoman aggression. In Britain, the incorporation of Scotland was completed, formally by the Union of 1707, effectively by the suppression of Jacobitism in 1746. +--------------------------------------------------------------------+ \| TIME-TABLE OF THE WORLD: A.D. 1500 to 1700 \| \| \| \| New World Entered, and East Re-entered. The Reformation. \| \| Organisation of European Nations under Absolute Monarchies. \| \| Constitutional Struggle in England. English Naval Supremacy \| +-----+--------------------------+-----------------------------+-----+ \|A.D. \| Asia and Africa \| Europe and America \|A.D. \| \|1500 \| \| \|1500 \| \| \| The New World bestowed \| Raphael, Michael Angelo, \| \| \| \| on Spain and Portugal \| and Titian. \| \| \| \| by the Bull of Pope \| Rivalry of Henry VIII. \| \| \| \| Alexander VI. \| (1509-47), Francis I. \| \| \| \| Portuguese dominion \| (1515-47), and Charles V. \| \| \| \| established in the \| (1519-56), who combines \| \| \| \| Indian seas by \| Spain, Burgundy, and the \| \| \| \| Albuquerque. \| Empire. \| \| \| \| Conquest of Egypt by \| Luther challenges the \| \| \| \| Ottoman Turks. \| Papacy, 1517-20. \| \| \| \| Safid dynasty in Persia \| The Reformation era opens. \| \| \| \| (“The Sofy”). \| \| \| \|1520 +--------------------------+-----------------------------+1520 \| \| \| First circumnavigation \| Turkish advance under \| \| \| \| completed, 1522. \| Solyman the Magnificent. \| \| \| \| Invasion of Hindostan \| Gustavus Vasa in Sweden, \| \| \| \| (Northern India) by \| 1523-60. \| \| \| \| Baber, the first \| Spain conquers Mexico (1520)\| \| \| \| “Mogul” emperor, 1526. \| Peru (1533). \| \| \| \| Expulsion of Moguls: \| REFORMATION: Subjection \| \| \| \| dynasty of Sher Shah \| of Church to Crown \| \| \| \| at Delhi, 1540. \| (England). Confession of \| \| \| \| \| Augsburg: Protestant \| \| \| \| \| League. Calvin creates \| \| \| \| \| Presbyterianism. \| \| \|1540 +--------------------------+-----------------------------+1540 \| \| \| \| RUSSIA: Ivan the Terrible. \| \| \| \| \| Order of Jesuits formally \| \| \| \| \| established. \| \| \| \| François Xavier in \| GERMANY: Contest between \| \| \| \| Japan. \| Charles V. and Protestant \| \| \| \| \| princes of Germany ended \| \| \| \| \| by compromise at Peace of \| \| \| \| \| Augsburg. \| \| \| \| Restoration of Moguls, \| ENGLAND: Protestant \| \| \| \| 1556. \| Revolution (Edward VI.) \| \| \| \| \| followed by Romanist \| \| \| \| \| reaction (Mary), and \| \| \| \| \| final establishment of \| \| \| \| \| Protestantism (Elizabeth) \| \| \| \| \| in England and Scotland. \| \| \|1560 +--------------------------+-----------------------------+1560 \| \| \| Rule of Akbar, 1556-1605.\| SPAIN: Philip II. and the \| \| \| \| Toleration of Hinduism. \| Inquisition. \| \| \| \| \| Council of Trent defines \| \| \| \| \| limits of Roman \| \| \| \| \| Catholicism. \| \| \| \| \| FRANCE: Series of civil \| \| \| \| \| wars of religion, \| \| \| \| \| 1562-95. \| \| \| \| \| Revolt of Netherlands from \| \| \| \| \| Spain. \| \| \| \| \| Turkish advance checked at \| \| \| \| \| Lepanto, 1571. \| \| \| \| \| PORTUGAL absorbed by Spain. \| \| \|1580 +--------------------------+-----------------------------+1580 \| \| \| Mogul dominion \| Gradual success of the \| \| \| \| established and \| Netherlands revolt. \| \| \| \| organised throughout \| English naval supremacy \| \| \| \| Northern India. \| proved by the Armada 1588.\| \| \| \| \| Decadence of Spain. \| \| \| \| \| FRANCE: Toleration secured \| \| \| \| \| by Henri IV. \| \| \| \| \| Spenser, Marlowe, and \| \| \| \| \| Shakespeare. \| \| \|1600 +--------------------------+-----------------------------+1600 \| \| \| Development of Japanese \| Galileo and Bacon. \| \| \| \| Feudalism. \| Union of English and \| \| \| \| Reign of Jehan Gir in \| Scottish Crowns, 1603. \| \| \| \| Hindostan, 1605-27. \| Dutch and English commerce \| \| \| \| First English factory at \| in the East Indies. \| \| \| \| Surat, 1611. \| Virginia, first successful \| \| \| \| First English Embassy to \| British colony in North \| \| \| \| Delhi, 1615. \| America, 1606. \| \| \| \| \| HOLLAND: Independence \| \| \| \| \| established, 1609. \| \| \| \| \| GERMANY: Thirty Years’ War \| \| \| \| \| begins, 1618-48. \| \| \|1620 +--------------------------+-----------------------------+1620 \| \| \| Reign of Shah Jehan, \| Gustavus Adolphus. \| \| \| \| 1627-58. \| FRANCE: Richelieu organises \| \| \| \| The Taj Mahal built. \| absolutism. \| \| \| \| End of the Portuguese \| ENGLAND: Constitutional \| \| \| \| power in the East. \| struggle between Charles \| \| \| \| Extension of the Mogul \| I. and Parliament. The \| \| \| \| dominion into the \| Petition of Right, 1628. \| \| \| \| Deccan. \| PORTUGAL recovers \| \| \| \| \| independence. \| \| \|1640 +--------------------------+-----------------------------+1640 \| \| \| Rise of the Manchu \| FRANCE: Rule of Mazarin: \| \| \| \| (Tartar) dynasty in \| absolutism established. \| \| \| \| China. \| ENGLAND: Civil War, \| \| \| \| \| resulting in military \| \| \| \| \| protectorate. \| \| \| \| Reign of Aurangzib, \| Thirty Years’ War ended by \| \| \| \| 1658-1707. \| Peace of Westphalia. \| \| \| \| Rise of the Mahrattas \| Commercial and naval rivalry\| \| \| \| under Sivaji. \| of English and Dutch. \| \| \| \| \| Development of France into \| \| \| \| \| the leading military \| \| \| \| \| power. \| \| \|1660 +--------------------------+-----------------------------+1660 \| \| \| France enters the field \| FRANCE: Louis XIV. initiates\| \| \| \| in India. \| policy of aggression. \| \| \| \| Revival of intolerant \| ENGLAND: Charles II. \| \| \| \| Mohammedanism by \| undermines supremacy of \| \| \| \| Aurangzib. \| Parliament. Repression of \| \| \| \| Expansion of the Mogul \| Nonconformity by \| \| \| \| Empire over Southern \| Parliament. \| \| \| \| India. \| Louis XIV. attacks Holland, \| \| \| \| \| with occasional support \| \| \| \| \| from Charles II. \| \| \| \| \| ENGLAND: Attack on Romanism.\| \| \|1680 +--------------------------+-----------------------------+1680 \| \| \| \| Aggressive movement of \| \| \| \| \| Turkey. \| \| \| \| \| FRANCE: Louis XIV. revokes \| \| \| \| \| Edict of Nantes, 1685. \| \| \| \| \| Constitutionalism \| \| \| \| \| established in England \| \| \| \| \| by the revolution of 1688.\| \| \| \| \| Wars of England and Holland \| \| \| \| \| against France. \| \| \|1700 \| \| RUSSIA: Peter the Great. \| 1700\| \|A.D. \| \| Newton and Leibnitz. \|A.D. \| +-----+--------------------------+-----------------------------+-----+ [Sidenote: Settling Down of the Powers] From 1739 to 1763 Europe was again plunged into wars, with an eight years’ interval. The motives of those wars, and of the combinations of states on either side, were complicated; the results were simple. Prussia, under Frederick the Great, emerged as a first-class Power; France lost her North American Colonies to Great Britain; the British East India Company defeated the attempt of the French to establish a paramount influence with the native princes, the Mogul Empire having broken up into a congeries of practically independent satrapies; and the British themselves became established as a territorial Power by the conquest of Bengal. Russia also, organised at the beginning of the century by Peter the Great, had taken her place definitely among the great Powers. During the next twenty years (1763-1783) Poland was absorbed by her neighbours. The British Empire was sundered by the revolt of the older American Colonies, which were established as the United States of America; while Canada remained loyal. By this time the whole of Europe was practically governed by absolute monarchies; but a cataclysm was at hand. France became the scene of a tremendous revolution. Crown and aristocracy were toppled into the abyss. [Sidenote: Napoleon and the Revolution] France proclaimed herself the liberator of the peoples; the monarchs of Europe combined to suppress the proletariat. During the last decade of the century one revolutionary constitution after another was set up in Paris, while the revolutionary armies shattered monarchical armies, and turned the “liberated” peoples into subject dependencies of the Republic. On the seas, however, Britain successfully asserted her supremacy. Of the commanders of the Republic, the most brilliant was the Corsican Bonaparte. He dreamed of making Egypt the basis for achieving an Asiatic empire, and thence overwhelming Europe; but the dream was shattered when he found himself isolated by Nelson’s destruction of the French fleet at Aboukir in the Battle of the Nile. Returning to Paris, he transformed the republic into an empire; he set up his brothers or his generals as rulers over half the kingdoms in Europe; he dictated terms to every government except Britain. Britain annihilated his fleets, and fought and beat his generals in the Spanish Peninsula. He conquered the kings, but the nations rose against him, and overthrew him; his last effort was crushed at Waterloo. Absolutism was reinstated, but the proletariats had learnt to demand freedom. Steam-power and steam-traction so changed the conditions of production as to revolutionise the relations between labour and capital, and between the landed and the manufacturing interests. In Great Britain political power passed from the landowners to the manufacturers with the great Reform Bill of 1832, and from the wealthy to the labouring classes with the Franchise Bills of 1867 and 1884. Every monarchy has been compelled to submit to limitations of its own powers more or less copied from Britain. [Sidenote: The World as it is] Britain herself, not untaught by the breach with America, has learned to establish responsible government in her Colonies, making them virtually free states; and among those states the idea of federation has taken root and is bearing fruit. In India, challenged by one native race after another, she has extended her sway over the whole peninsula, and has abolished the anomaly of governing her great dependency through a trading company. In the West her kinsmen have raised the United States into a mighty nation. In Europe France has passed through monarchy and republic and second empire into a stable republic; Italy has revolted against foreign rulers, and become a united nation; the small peoples of the Balkan Peninsula have now achieved by arms their liberty from Turkish rule. Prussia has won the hegemony of the German states, and established a new German Empire. Russia, the bogey of the West, and of Britain in particular, has shown her weakness in collision with the sudden development of Japan. Finally, the Dark Continent has been explored and partitioned: in the south, after a sharp conflict, British and Dutch are on the way to become a united people; in the north, Egypt has been reorganised under British administration. We end, as we began, with the land of the Pyramids. ARTHUR D. INNES. +--------------------------------------------------------------------+ \| TIME-TABLE OF THE WORLD: A.D. 1700 to 1914 \| \| \| \| Struggle for Colonial Supremacy. French Revolution and Napoleonic \| \| Wars. Growth of Democracy and Consolidation of European States. \| \| Colonial Extension of Responsible Government \| +-----+--------------------------+-----------------------------+-----+ \|A.D. \| Asia, Africa, and \| Europe and America \|A.D. \| \|1700 \| Australasia \| \|1700 \| \| \| \| \| \| \| \| \| War of Spanish Succession, \| \| \| \| \| 1702-13. Bourbons \| \| \| \| \| established in Spain. \| \| \| \| \| Career of Charles XII. of \| \| \| \| \| Sweden, 1697-1718. \| \| \| \| \| GREAT BRITAIN: Incorporating\| \| \| \| \| union of England and \| \| \| \| \| Scotland, 1707. \| \| \| \| \| Turkish advance decisively \| \| \| \| \| stopped by Eugene, 1717. \| \| \| \| \| Alliance of France and \| \| \| \| \| Great Britain. \| \| \|1720 +--------------------------+-----------------------------+1720 \| \| \| \| Anglo-Spanish War, combined \| \| \| \| \| with War of the Austrian \| \| \| \| \| Succession, 1739-48. \| \| \| \| \| Development of Prussian \| \| \| \| \| military power under \| \| \| \| \| Frederick William. \| \| \|1740 +--------------------------+-----------------------------+1740 \| \| \| Struggle between British \| GREAT BRITAIN: End of \| \| \| \| and French in Southern \| Jacobitism (the \| \| \| \| India, 1746-61. \| Forty-five) consolidates \| \| \| \| \| the union. \| \| \| \| \| Seven Years’ War (1756-63): \| \| \| \| \| Prussia and Great Britain \| \| \| \| \| against France, Austria, \| \| \| \| Clive conquers Bengal; \| and Russia. Achievements \| \| \| \| beginning of British \| of Frederick. Overthrow of\| \| \| \| territorial power in \| France at sea, and in \| \| \| \| India, 1757. \| Canada and India. \| \| \|1760 +--------------------------+-----------------------------+1760 \| \| \| British dominion receives\| Treaties of Paris and \| \| \| \| Mogul’s sanction. \| Hubertsburg exclude France\| \| \| \| \| from America and India, \| \| \| \| \| and confirm the position \| \| \| \| \| of Prussia. \| \| \| \| Haidar Ali in Mysore. \| Partition of Poland. \| \| \| \| Governor-Generalship of \| GREAT BRITAIN: Quarrel \| \| \| \| Warren Hastings \| with Colonies; leading to \| \| \| \| (1774-85), establishes \| War of American \| \| \| \| the British power. \| Independence, 1775-83. \| \| \|1780 +--------------------------+-----------------------------+1780 \| \| \| Dual control in India by \| British recovery of naval \| \| \| \| East India Company and \| predominance. \| \| \| \| Parliamentary Board of \| UNITED STATES: Independence \| \| \| \| Control set up by \| established 1783. \| \| \| \| Pitt’s India Act. \| FRANCE: French Revolution, \| \| \| \| \| 1789. \| \| \| \| Administration of British\| War between European \| \| \| \| India systematised. \| Coalitions and French \| \| \| \| \| Republic, 1792-1802. Rise \| \| \| \| \| of Bonaparte. Triumphs of \| \| \| \| \| French Army and British \| \| \| \| Overthrow of Mysore, and \| Navy. \| \| \| \| and institution of \| GREAT BRITAIN: Legislative \| \| \| \| subsidiary alliances by\| Union with Ireland. \| \| \| \| Lord Wellesley. \| Kant and Goethe. \| \| \|1800 +--------------------------+-----------------------------+1800 \| \| \| Overthrow of Mahratta \| War renewed (1803) between \| \| \| \| power by Lord Hastings \| European Coalitions and \| \| \| \| (1819): extensive \| Emperor Napoleon (1804). \| \| \| \| annexations. \| Trafalgar and Austerlitz, \| \| \| \| Acquisition of Cape \| 1805. Peninsula War, \| \| \| \| Colony from Holland by \| 1808-13. Moscow Campaign, \| \| \| \| Great Britain. \| 1812. Waterloo Campaign, \| \| \| \| Gradual planting of \| 1815. \| \| \| \| Australasian Colonies. \| European reconstruction. \| \| \| \| \| Absolutist reaction: the \| \| \| \| \| Holy alliance. \| \| \|1820 +--------------------------+-----------------------------+1820 \| \| \| \| Independence of South and \| \| \| \| \| Central American States. \| \| \| \| \| Greek War of Independence, \| \| \| \| \| 1822-29. \| \| \| \| Aggressive Eastward \| FRANCE: Constitutional \| \| \| \| movement of Persia \| Monarchy under Louis \| \| \| \| checked at Herat. \| Philippe, 1830-48. \| \| \| \| First Afghan Wars, \| GREAT BRITAIN: Parliamentary\| \| \| \| 1839-42. \| Reform and manufacturing \| \| \| \| CHINA: First collision \| development. Railways. \| \| \| \| with Europe. \| \| \| \|1840 +--------------------------+-----------------------------+1840 \| \| \| Sikh Wars, 1845-49. \| Charles Darwin. \| \| \| \| Annexations under \| Revolutionary movements in \| \| \| \| Dalhousie. \| Europe. \| \| \| \| Indian Mutiny, 1857. \| FRANCE: Republic (1849) \| \| \| \| Transfer of Indian \| passing to Empire of \| \| \| \| Government to British \| Napoleon III. (1852). \| \| \| \| Crown, 1858. \| Crimean War, 1854-56. \| \| \| \| JAPAN: Admission of \| Establishment of responsible\| \| \| \| foreign traders. \| government in British \| \| \| \| \| Colonies. \| \| \|1860 +--------------------------+-----------------------------+1860 \| \| \| JAPAN: Revived power of \| American Civil War, \| \| \| \| the Mikado. \| 1861-65. Abolition of \| \| \| \| \| Slavery. \| \| \| \| Advance of Russia in \| Independence of United Italy\| \| \| \| Central Asia towards \| under Victor Emmanuel. \| \| \| \| India. \| Prussia acquires leadership \| \| \| \| \| of German States 1866. \| \| \| \| Second Afghan War, \| Franco-Prussian War, \| \| \| \| 1878-80. \| 1870-71. New German \| \| \| \| \| Empire, and new French \| \| \| \| \| Republic. \| \| \| \| \| Russo-Turkish War, 1877-78. \| \| \|1880 +--------------------------+-----------------------------+1880 \| \| \| Mahdism in the Eastern \| British control established \| \| \| \| Sudan; ended at \| in Egypt. \| \| \| \| Omdurman in 1898. \| Repeated disturbances in the\| \| \| \| British control \| Balkan States established \| \| \| \| established. \| by the Russo-Turkish War. \| \| \| \| Partition of Africa into \| First Peace Conference of \| \| \| \| “Spheres of Influence.”\| European powers at the \| \| \| \| War between China and \| Hague, 1899. \| \| \| \| Japan. \| Norway separates from \| \| \| \| Annexation of Philippines\| Sweden and elects King \| \| \| \| by United States. \| Haakon, 1905. \| \| \| \| South African War \| Second Peace Conference at \| \| \| \| (1899-1902) and \| the Hague, 1907. \| \| \| \| incorporation of Dutch \| \| \| \| \| States into British \| \| \| \| \| Empire. \| \| \| \| \| Federation of Australian \| \| \| \| \| Colonies, 1901. \| \| \| \| \| War between Russia and \| \| \| \| \| Japan, 1904-5. \| \| \| \|1910 +--------------------------+-----------------------------+1910 \| \| \| CHINA: Revolution: Manchu\| Allied Balkan States defeat \| \| \| \| dynasty displaced by \| Turkey, 1912. \| \| \| \| Republic, 1912. \| Creation of Albania as \| \| \| \| Tripoli annexed by Italy \| independent state, 1914. \| \| \| \| from Ottoman Empire, \| Revolution in Mexico, \| \| \|A.D. \| 1912. \| 1913-14. \|A.D. \| +-----+--------------------------+-----------------------------+-----+ A TIME-TABLE OF THE NATIONS OF THE WORLD FROM THE BEGINNING OF HISTORY TO THE PRESENT DAY Showing at a glance the fate of all nations, their rise, their sway, their decline, and their successors On this double-page are shown the empires of the ancient world to the rise of Rome, and on the succeeding double-page the ruling powers from Rome until the present day. The chronology is in divisions of a hundred years, except the first four, which, for convenience of space, are shown in longer periods NOTABLE EVENTS B. C. 8000 The earliest civilisation known is that of Egypt, traces of which have been found dating back to 7,000 or 8,000 B.C. Equally early civilisations were probably established in the Euphrates Valley. 4000 In the fifth millennium Khufu built the Great Pyramids; in the fourth a Semitic migration, spreading westward from Asia, peopled Babylonia, Assyria, Canaan, and Phœnicia afresh, establishing new nations and kingdoms. 3000 The third millennium saw the Aryan invasion of India; the beginning of Chinese history; and Aryan and Semitic waves of migration towards Europe. 2000 ---------------------------------------------------------------- Egypt was conquered by the Hyksos, a Semitic nomadic race. 1500 Hittite Empire established in Syria. During the next three hundred years, of which the history is obscure, the dynasty of the Ramesides was established in Egypt, which waged wars with the Hittite Empire. Rameses 1400 II. is popularly identified with the Pharaoh of the Exodus, an event which is also identified with the expulsion of the Hyksos. The supremacy in the Mesopotamian regions alternates 1300 between Assyrian and Babylonian dynasties. ---------------------------------------------------------------- 1200 Rise of a Hebrew nation. Age of Phœnician prosperity; commercial importance of Sidon and Tyre. ---------------------------------------------------------------- 1100 Ionic and Doric migrations. Predominance of Phrygia among kingdoms of Asia Minor. 1048 B.C. David captures Jerusalem and becomes King over all Israel. ---------------------------------------------------------------- 1000 ] JAPAN CHINESE EMPIRE INDIA PARTHIAN EMPIRE ARABIA ROMAN EMPIRE BRITAIN ] ---------------------------------------------------------------- 1000 975 B.C. Division of the Hebrew kingdom into Judah and Israel after the death of Solomon. Growth of the Hellenic States. The age of Homer. ---------------------------------------------------------------- 900 850 B.C. Foundation of Carthage. Beginnings of the Latin and Etruscan peoples. ---------------------------------------------------------------- 800 Assyrian conquest of Babylon, Syria, and Israel. 753 B.C. The foundation of Rome. Rapid spread of the Greek Colonies. ---------------------------------------------------------------- 700 Beginnings of the Macedonian kingdom. Rise of Media. Beginnings of Japanese history. Decline of Assyria, fall of Nineveh, and establishment of new Babylonian Empire. ---------------------------------------------------------------- 600 Cyrus, King of Persia, conquers Media, establishes his empire over Lydia, Assyria, and Babylonia (538 B.C.). His son Cambyses conquers Egypt, 525 B.C. ---------------------------------------------------------------- 500 The Greek States revolt against Persia and are triumphant. Egypt regains independence. Steady growth of Roman ascendancy in Italy. Struggle between Athens and Sparta. ---------------------------------------------------------------- 400 Conquests of Alexander the Great (334-322 B.C.). He conquers Persia, masters Egypt, and invades India. At his death his empire is divided: Egypt falls under the Ptolemies, Syria under the Seleucidæ. ---------------------------------------------------------------- 300 Babylon absorbed by Parthian Empire. Carthage dominates Spain. Wars between Rome and Carthage. Overthrow of Carthage (202 B.C.). ---------------------------------------------------------------- 200 Judea attains independence under the Maccabees. Growing power of Rome. Macedon a Roman province; Egypt and Syria made Roman protectorates. The Greek States are absorbed into province of Macedon. ---------------------------------------------------------------- 100 Cæsar conquers Gaul and lands in Britain. Egypt becomes a Roman province. Augustus Cæsar. Establishment of the Roman Empire. B.C. [Illustration: FROM THE BEGINNING OF THE CHRISTIAN ERA TO THE PRESENT DAY JAPAN CHINESE EMPIRE INDIA PARTHIAN EMPIRE ARABIA ROMAN EMPIRE BRITAIN] ---------------------------------------------------------------- NOTABLE EVENTS ---------------------------------------------------------------- For the first four centuries of the Christian era the Roman Empire absorbed the “known” world, bounded in Europe by the ocean, the Rhine, and the Danube, and in Asia by the Euphrates, and including the Mediterranean districts of Africa. Germanic tribes bore with ever-increasing pressure upon her European borders, and the Parthians defied her in the East. At the close of the third century the centre of political gravity was passing from Rome itself to Byzantium, preparing for the scission of the Empire, into Eastern and Western, which was practically at the close of the fourth century, when it was becoming increasingly clear that Rome could not stand against the Barbarian invaders, notably the Goths under Alaric. ---------------------------------------------------------------- In the fifth century the Empire, long weakened by corruption and the tyranny of the army, was overwhelmed by the Barbarians. Vandals, Western Goths, and Suevi poured into Spain; Franks and Alemanni spread over Gaul; Ostro-Goths and Lombards settled in North Italy; Huns and Avars attacked Thrace. Britain was invaded by Saxons, Jutes, and Angles. ---------------------------------------------------------------- The seventh and eighth centuries were marked by the rapid rise of Mohammedanism in Arabia; the conquests of the Saracens in Egypt, Africa, and West Asia; the establishment of the Caliphate at Bagdad; and their invasion of Spain. Here they were checked by the Franks. Charlemagne, son of Pippin, King of the Franks in Germany and Gaul, was crowned in 768, conquered Lombardy in 774, calling himself “King of the Franks and Lombards and Patrician of the Romans.” His empire was divided after his death; from it emerged modern France and Germany. His coronation by the Pope at Rome (A.D. 800) originated the idea of the Holy Roman Empire. ---------------------------------------------------------------- JAPAN CHINESE EMPIRE {BRITISH {INDIAN {EMPIRE AFGHANISTAN PERSIA ARABIA EGYPT TURKEY {BALKAN {STATES GREECE RUSSIAN EMPIRE ITALY AUSTRO-HUNGARY GERMAN EMPIRE BELGIUM HOLLAND SWITZERLAND FRANCE PORTUGAL {SOUTH {AMERICAN {STATES SPAIN MEXICO MOROCCO GREAT BRITAIN & IRELAND UNITED STATES DENMARK NORWAY SWEDEN ---------------------------------------------------------------- Disintegration of the Empire of the Caliphs, and rise in Asia Minor of the Seljuk Turks, making war against the Byzantine Empire and the Crusaders, and conquering Egypt. India is invaded by Mohammedan Afghan rulers, who eventually establish a dynasty at Delhi. ---------------------------------------------------------------- The Kingdoms of Hungary, Bohemia, and Poland, converted to Christianity in the tenth century, come into increasing prominence. The Kings of Castile, Navarre, Aragon and Portugal war against the Moors, who (A.D. 1248) are restricted to Granada. The Mamelukes (Slave kings) conquer Egypt (1252). Switzerland attains independence. ---------------------------------------------------------------- Failure of England to absorb Scotland, or to conquer France. The Hundred Years’ War. ---------------------------------------------------------------- The Turks capture Constantinople (1453). The Netherlands (Burgundy) united to the House of Hapsburg. (1477). Spain united; overthrow of the Moorish dominion. ---------------------------------------------------------------- Bohemia and Hungary united to Austria. Spain and Portugal take possession of the New World. Mogul Empire established in Hindostan. The Reformation leads to revolt of the Netherlands from Spain; Spain absorbs Portugal. ---------------------------------------------------------------- Union of English and Scottish crowns (1603); followed by legislative union (1707). Disruption of Germany in the Thirty Years’ War. Establishment of English Colonies in America. Portugal recovers independence. ---------------------------------------------------------------- Spain becomes a Bourbon Power. Rise of Russia and Prussia. Partition of Poland between Russia, Prussia and Austria. Further disintegration of German Empire. British dominion in India and North America. Independence of United States. ---------------------------------------------------------------- France predominant under Napoleon. Rise of South American States. Establishment of British India. Italy independent. Egypt, Greece, and Balkan States freed from Turkey. Foundation of German Empire. ---------------------------------------------------------------- Independence of Norway (1905). ---------------------------------------------------------------- +-------------------------------------------+ \| CONTEMPORARY FIGURES IN HISTORY \| +------+------------------------------------+ \| TIME \| \| \| B.C. \| \| +------+--------------+---------------------+ \| 500 \|India \|Buddha \| \| +--------------+---------------------+ \| \|China \|Confucious \| \| +--------------+---------------------+ \| \|Persia \|Darius \| \| \| \|Xerxes \| \| +--------------+---------------------+ \| \|Greece \|Æschylus \| \| \| \|Themistocles \| \| +--------------+---------------------+ \| \|Rome \|Tarquin the Proud \| \| +--------------+---------------------+ \| \|Judah \|Haggai \| \| \| \|Zechariah \| \| +--------------+---------------------+ \| 450 \|Persia \|Artaxerxes \| \| +--------------+---------------------+ \| \|Greece \|Socrates \| \| \| \|Plato \| \| \| \|Pericles \| \| \| \|Herodotus \| \| \| \|Thucydides \| \| \| \|Sophocles \| \| +--------------+---------------------+ \| \|Judah \|Nehemiah \| \| \| \|Ezra \| \| +--------------+---------------------+ \| 400 \|Greece \|Euripides \| \| +--------------+---------------------+ \| 350 \|Greece \|Aristotle \| \| \| \|Demosthenes \| \| +--------------+---------------------+ \| \|Macedon \|Philip \| \| \| \|Alexander \| \| +--------------+---------------------+ \| 200 \|Rome \|Hannibal \| \| +--------------+---------------------+ \| \|Judah \|Judas Maccabæus \| \| +--------------+---------------------+ \| 50 \|Rome \|Julius Cæsar \| \| \| \|Cicero \| \| +--------------+---------------------+ \| \|Egypt \|Cleopatra \| \| +--------------+---------------------+ \|Jesus \|Rome \|Augustus \| \|Christ\| \|Tiberius \| \| \| \|Horace \| \| \| \|Virgil, Livy \| \| +--------------+---------------------+ \| \|Judah \|John the Baptist \| +------+--------------+---------------------+ +------+------------------------------------+ \| A.D. \| \| +------+--------------+---------------------+ \| 50 \|Britain \|Boadicea \| \| +--------------+---------------------+ \| \|Rome, Italy \|Seneca \| \| \| \|St. Paul \| \| +--------------+---------------------+ \| \|Africa & East \|Josephus \| \| +--------------+---------------------+ \| 300 \|Rome, Italy \|Constantine \| \| +--------------+---------------------+ \| \|Africa & East \|Athanasius \| \| +--------------+---------------------+ \| 400 \|Rome, Italy \|Alaric \| \| +--------------+---------------------+ \| \|Africa & East \|Augustine \| \| +--------------+---------------------+ \| 600 \|France \|Chas Matel \| \| +--------------+---------------------+ \| 700 \|Britain \|Bede \| \| +--------------+---------------------+ \| 800 \|Britain \|Alfred \| \| +--------------+---------------------+ \| \|France \|Charlemagne \| \| +--------------+---------------------+ \| \|Africa & East \|Haroun-al-Raschid \| \| +--------------+---------------------+ \| 1100 \|Spain \|The Cid \| \| +--------------+---------------------+ \| \|Africa & East \|Omar Khayyam (Persia)\| \| +--------------+---------------------+ \| 1200 \|Rome, Italy \|St. Francis \| \| +--------------+---------------------+ \| 1300 \|Britain \|Chaucer \| \| +--------------+---------------------+ \| \|Switzerland \|William Tell \| \| +--------------+---------------------+ \| \|Rome, Italy \|Aquinas \| \| \| \|Dante \| \| +--------------+---------------------+ \| \|Africa & East \|Tamerlane \| \| +--------------+---------------------+ \| 1350 \|Britain \|Wycliffe \| \| +--------------+---------------------+ \| \|France \|Froissant \| \| +--------------+---------------------+ \| \|Switzerland \|Arnold von Winkelried\| \| +--------------+---------------------+ \| \|Rome, Italy \|Petrarch \| \| \| \|Boccaccio \| \| +--------------+---------------------+ \| \|Africa & East \|Hafiz (Persia) \| \| +--------------+---------------------+ \| 1450 \|Britain \|Caxton \| \| +--------------+---------------------+ \| \|Rome, Italy \|Da Vinci \| \| +--------------+---------------------+ \| 1500 \|Britain \|Knox \| \| \| \|Latimer \| \| +--------------+---------------------+ \| \|France \|Rabelais \| \| +--------------+---------------------+ \| \|Germany \|Luther \| \| \| \|Copernicus \| \| +--------------+---------------------+ \| \|Switzerland \|Calvin \| \| +--------------+---------------------+ \| \|Rome, Italy \|Columbus \| \| \| \|Savonarola \| \| \| \|Machiavelli \| \| +--------------+---------------------+ \| \|Spain \|Ignatius Loyola \| \| \| \|St. Theresa \| \| \| \|Ferdnd. & Isabella \| \| \| \|Cortez \| \| +--------------+---------------------+ \| 1550 \|Britain \|Philip Sidney \| \| \| \|Spenser \| \| +--------------+---------------------+ \| \|France \|Montaigne \| \| \| \|Scaliger \| \| +--------------+---------------------+ \| \|Rome, Italy \|Cellini \| \| \| \|Tasso \| \| +--------------+---------------------+ \| \|Spain \|Alva \| \| +--------------+---------------------+ \| \|Netherlands \|William the Silent \| \| +--------------+---------------------+ \| \|Russia \|Ivan the Terrible \| \| +--------------+---------------------+ \| 1600 \|Britain \|Shakespeare \| \| \| \|Raleigh \| \| \| \|Bacon \| \| \| \|Jonson \| \| +--------------+---------------------+ \| \|France \|Corneille \| \| \| \|Richelieu \| \| \| \|Descartes \| \| +--------------+---------------------+ \| \|Germany \|Kepler \| \| +--------------+---------------------+ \| \|Rome, Italy \|Galileo \| \| +--------------+---------------------+ \| \|Spain \|Cervantes \| \| +--------------+---------------------+ \| \|Scandinavia \|Gustavus Adolphus \| \| +--------------+---------------------+ \| \|Netherlands \|Rubens \| \| \| \|Van Dyck \| \| \| \|Grotius \| \| +--------------+---------------------+ \| 1650 \|Britain \|Cromwell \| \| \| \|Milton \| \| \| \|Bunyan \| \| \| \|Dryden \| \| \| \|Locke \| \| \| \|Hobbes \| \| +--------------+---------------------+ \| \|France \|Pascal \| \| \| \|Racine \| \| \| \|Molière \| \| \| \|Fénélon \| \| \| \|Rochefoucauld \| \| \| \|Louis XIV. \| \| +--------------+---------------------+ \| \|Germany \|Leibnitz \| \| +--------------+---------------------+ \| \|Netherlands \|Spinoza \| \| +--------------+---------------------+ \| \|Russia \|Peter the Gt. & \| \| \| \| Catherine \| \| +--------------+---------------------+ \| 1700 \|Britain \|Swift \| \| \| \|Steele \| \| \| \|Addison \| \| \| \|Walpole \| \| +--------------+---------------------+ \| \|Germany \|Handel \| \| +--------------+---------------------+ \| \|Scandinavia \|Holberg \| \| +--------------+---------------------+ \| 1750 \|Britain \|Chatham \| \| \| \|Burke \| \| \| \|Pitt and Fox \| \| \| \|Wesley \| \| \| \|Burns \| \| \| \|Goldsmith \| \| \| \|Sheridan \| \| \| \|Dr. Johnson \| \| \| \|Coleridge \| \| \| \|Flaxman \| \| \| \|Reynolds \| \| \| \|Gainsboro’gh \| \| \| \|Nelson \| \| \| \|Wellington \| \| +--------------+---------------------+ \| \|France \|Voltaire \| \| \| \|Lavoisier \| \| \| \|Napoleon \| \| +--------------+---------------------+ \| \|Germany \|Fredk the Gt \| \| \| \|Goethe \| \| \| \|Schiller \| \| \| \|Haydn \| \| \| \|Mozart \| \| \| \|Kant \| \| +--------------+---------------------+ \| \|Switzerland \|Rousseau \| \| \| \|Gessner \| \| \| \|Pestalozzi \| \| +--------------+---------------------+ \| \|America \|Franklin \| \| \| \|Washington \| \| +--------------+---------------------+ \| 1800 \|Britain \|Faraday \| \| \| \|Scott \| \| \| \|Byron \| \| \| \|Keats \| \| \| \|Shelley \| \| \| \|Wordsworth \| \| \| \|Lamb \| \| +--------------+---------------------+ \| \|Germany \|Hegel \| \| \| \|Beethoven \| \| +--------------+---------------------+ \| \|Scandinavia \|Tegner \| \| \| \|Thorwaldsen \| \| +--------------+---------------------+ \| 1825 \|Britain \|Gladstone \| \| \| \|Macauley \| \| \| \|Disraeli \| \| \| \|Landseer \| \| \| \|Mill \| \| \| \|Livingstone \| \| \| \|Ruskin \| \| \| \|Dickens \| \| \| \|Carlyle \| \| \| \|Thackeray \| \| \| \|Browning \| \| \| \|Tennyson \| \| \| \|Darwin \| \| \| \|Huxley \| \| \| \|Spencer \| \| +--------------+---------------------+ \| \|France \|Balzac \| \| \| \|Dumas \| \| \| \|Victor Hugo \| \| \| \|Georges Sand \| \| \| \|Lesseps \| \| \| \|Napoleon 3 \| \| \| \|Gambetta \| \| +--------------+---------------------+ \| \|Germany \|Wagner \| \| \| \|Heine \| \| \| \|Bismarck \| \| \| \|Moltke \| \| \| \|William I. \| \| +--------------+---------------------+ \| \|Rome, Italy \|Garibaldi \| \| \| \|Mazzini \| \| \| \|Cavour \| \| \| \|Victor Emmanuel \| \| +--------------+---------------------+ \| \|Scandinavia \|Hans Andersen \| \| \| \|Runeberg \| \| \| \|Wergeland \| \| \| \|Welhaven \| \| \| \|Ibsen \| \| \| \|Bjornson \| \| +--------------+---------------------+ \| \|America \|Irving \| \| \| \|Emerson \| \| \| \|Longfellow \| \| \| \|Whittier \| \| \| \|Lowell \| \| \| \|Holmes \| \| \| \|Lincoln \| \| +--------------+---------------------+ \| \| Russia \|Turgenieff \| \| \| \|Tolstoy \| \| +--------------+---------------------+ \| \| Hungary \|Kossuth \| \| +--------------+---------------------+ \| 1900 \| \| \| +------+--------------+---------------------+ [Illustration: MAKING OF THE EARTH AND THE COMING OF MAN] THE BEGINNING OF THE EARTH BY PROFESSOR SOLLAS The origin of our planet is a problem which has appealed to the intellect of thoughtful men from the most remote times, and the earliest recorded speculations concerning it--those of the Mosaic cosmogony--possess a peculiar interest, since they embody the views of the ancient Chaldeans, who were not only systematic observers of the heavens, but made practical use of their results. [Sidenote: Beginning of a Famous Theory] The Mosaic cosmogony is not unworthy of the great people among whom it took its rise; it recognises the fact that the earth had a history antecedent to the advent of man, and its account of the order of events in this history is not only remarkable as a feat of _a priori_ reasoning, but accords in some respects with the results achieved after much labour by modern science. It was not until the middle of the eighteenth century that the reign of evolution began, and attempts were made to trace the history of a planetary system from its source in a primeval nebula on purely mechanical grounds. Swedenborg (1735) was the pioneer in this direction, then came Thomas Wright (1750) of Durham, whose work furnished inspiration to Emanuel Kant (1755), and led him to construct a consistent scheme of the Universe. The last of this group of cosmic philosophers is Laplace (1796), whose admirable description of the evolution of the solar system was arrived at independently, and without knowledge of the previous work of Kant. Laplace assumed as his starting-point the existence of a nebula formed of incandescent gas, and extending beyond the limits of the outermost planet of our system. It was in rotation about a central axis, and possessed in consequence a disc-like or lenticular form. Radiating its heat away in all directions through surrounding space, it grew continually colder, and in cooling diminished in bulk. As a consequence of this contraction its rate of rotation increased, till at length the centrifugal force of the outermost part became so great that this could no longer continue to follow the contracting mass within, and thus remained behind as a great rotating ring. The continued contraction of the internal mass, and the resulting increase in the velocity of rotation, again brought about the same condition of things, and a fresh ring was left behind. [Sidenote: Cooling of the Nebula] This process was repeated time after time, till as many rings were formed as there are planets in the solar system; the central mass which survived within the innermost ring condensed to form the sun. The rings were highly unstable--that is to say, a slight disturbing force was sufficient to destroy their continuity; they broke across and rolled up into great nebulous globes, which revolved round the sun in the same direction as the original nebula, and rotated on their axes in the same direction as that in which they revolved. Most of them repeated the behaviour of the original nebulæ, leaving behind rings as they contracted, and these rings either rolled up to form moons or satellites, or, in the solitary instance of Saturn’s rings, retained their annular form. The rings are now known to consist of a multitude of solid bodies, as proved by Clerk-Maxwell. [Sidenote: The Temperature of the Earth] By this hypothesis, so beautiful in its simplicity, an explanation was afforded embracing all the more important facts of our system; the revolution of all the planets in nearly circular orbits and in the same direction as that in which the sun rotates, and the revolution of their satellites, also in circular orbits and in the same direction as their primaries; the comparatively high temperature and consequent low density of the larger planets and the sun, as well as a variety of other phenomena, all seem to follow naturally from it. The fundamental assumption seems to be in harmony with a number of known facts. Thus in the case of our own planet the volcanoes distributed around the margins of the oceans, and the hot springs scattered irregularly over the whole terrestrial surface, suggest that great stores of heat exist beneath our feet, a presumption which finds confirmation in the fact that whenever we descend towards the interior of the earth, as in deep mines or wells, the temperature continues steadily to rise after we have passed a depth below which seasonal and diurnal changes of temperature cease to be felt, the rise being in some cases as much as 3 deg. for 100 ft., in others only 1 deg. for the same distance, but on the average 1 deg. for 60 ft. or 70 ft. If this increase of temperature continues down to great depths, and there seems to be no reason why it should not, then a point will be reached, say, at thirty or forty miles down, where the interior will attain a white heat. [Sidenote: The Earth as a Star] Thus the earth might be regarded as a white hot body surrounded with a film of rock growing continually cooler towards the surface. But such a hot body suspended in space must be cooling, just as all bodies which are hotter than their surroundings. It is cooler to-day than it was yesterday, or--what is the same thing--it was hotter yesterday than it is to-day, and so of all previous yesterdays. And thus as we travel backwards in time we perceive that the earth will be growing hotter, the level of white heat will be mounting upwards towards the surface, and will at last reach it, so that the earth, instead of being, as it now is, a dark body shining only with the reflected light of the sun, will be self-luminous, a tiny star of a magnitude so diminutive as to have awakened resentment on the part of some terrestrial inhabitants, who have regarded it as disproportionate to their dignity. But we cannot arrest imagination at this stage; our thought still extends its retrospective glance into the abyss of past time, and we perceive the earth still growing hotter, till its temperature transcends those limits at which it can exist in the solid state. It becomes molten--nay, more, it becomes gaseous, and thus resumes the nebular state from which it sprang. Precisely the same argument applies to the sun; our mighty luminary is also a cooling body, and if we could restore to it the heat which it has lost in the course of past æons it would resume a completely gaseous state. Modified in one way or another, this chain of reasoning seemed irrefragable in those happy days which preceded the discovery of radium. [Sidenote: Universe still in Evolution] The question may be considered from another point of view. On searching the heavens we find that many of the stages which are assumed in Laplace’s hypothesis are still represented by actual existences. There are, to begin with, those immense diffused nebulæ, almost incapable of definition, which are proved, on spectroscopic examination, to emit that kind of light which is characteristic of glowing gas; from these we pass to others which are resolvable by the telescope into a central and more condensed nucleus, with two mighty nebulous arms whirled round in a spiral, and bearing more condensed masses in their midst; even ring nebulæ are known to exist; and, finally, there are nebulous halos which surround some of the stars. Then we come to the stars themselves, which are suns of various degrees of magnitude, some immensely larger than our own luminary, and these are evidently in various stages of existence. Some are blue, and afford evidence of a higher temperature than that of our sun; others are yellow, and make a nearer approach to the solar temperature; while, again, others are red, and certainly colder. These, in conjunction with other considerations, lead to the conviction that the universe is in a state of evolution, and that the solar system at one time existed in a nebular state. But whether Laplace’s description of the series of events through which the original nebula passed is the true one or not is a very different matter; it presents so many difficulties that scarcely any student now supports it. In the beginning, it is supposed that the earth was part of a vast nebula of gaseous matter and meteorites, resembling the nebula of Argo, illustrated above. Later, as the cooling process advanced, the nebula assumed a rotatory movement in the form of a spiral. The nebula of Andromeda affords an excellent illustration of this. Another stage would be as in the annular nebula of Aquaris, the mass forming into a ball with the outer ring attached. HOW THE HEAVENS TELL THE STORY OF THE ORIGIN OF THE EARTH] Or, like the nebula of Cygni, with the central sun well formed and the gaseous ring far removed, the earth would begin to shape, and the ring would roll up to form the moon. Jupiter, which is in a molten state, wreathed in thick vapour, with the “great red spot” indicating the beginning of the solidifying process, shows what the earth was like before it assumed its present solid condition. This shows the earth and the moon in their relative sizes; while the diagram below it illustrates the distance apart. ] [Sidenote: Laplace’s Theory Abandoned] A fundamental difficulty is the extreme tenuity of the gas which is assumed to have formed the planetary rings. A second difficulty, which has been emphasised by Professors Chamberlin and Moulton, is to be found in the comparatively small amount of rotational energy which the system at present possesses, for this is less than 1/200 of that which, on the most favourable assumption, must have been contained within the original nebula. Less fundamental, but equally fatal, is the fact that one of the satellites of Saturn revolves round its primary in a direction opposed to that of the rotation of the planet itself. [Recently Mr. Stratton, following out a suggestion of Professor W. H. Pickering, has shown that this is quite consistent, and, indeed, is a natural deduction from Laplace’s hypothesis.] Hence for these and other reasons we are reluctantly compelled to abandon an hypothesis which for over a century has exercised an influence on our conception of the cosmos not less profound, penetrating, and far-reaching than that of the famous Darwinian doctrine of natural selection, now on its trial. [Sidenote: What are the Nebulæ?] At present, unanimity of opinion, even on questions of the most primary kind, is far to seek. Philosophers are not even agreed as to the constitution of the nebulæ. It is questioned whether even those least resolvable and most diffused forms which give bright line spectra really consist of masses of incandescent gas. Many observers, among them Sir Norman Lockyer, now maintain that they are formed of swarms of meteorites, which, moving with prodigious velocity, meet in frequent collision, and by their impact evolve sufficient heat to become self-luminous. Others, again, like the distinguished investigator Arrhenius, while admitting the gaseous nature of these nebulæ, deny that they are incandescent, and assert that their temperature is not much above that of surrounding space. Their exterior parts consist of the lighter gases in a highly rarefied state, and minute particles of negative electricity, which are always careering through space, on penetrating these gases produce a luminous discharge. A nebula composed of swarms of meteorites would, as Sir George Darwin has shown, behave very much in the same way as one composed of gas, and if in rotation would rotate as a solid mass. The meteorites would stand in the same relation to the nebula as molecules to a gas, and thus the question of the constitution of the nebula, although of great interest in itself, becomes of subsidiary importance in tracing its subsequent history. [Sidenote: Shaping of the Planets] One of the latest attempts to frame a nebular hypothesis is that of Professor J. H. Jeans. His reasoning is of a highly mathematical character, and his conclusions are expressed in the most general terms. Starting with a spherical nebula of gas or meteorites endowed with a small amount of rotation, he shows that as it cools or loses energy the temperature of the interior will not fall continuously in precise correspondence with the cooling of the outer parts, and this “lag” of the interior temperature will bring about a tendency to instability. The contraction of the nebula due to cooling will increase the velocity of rotation, and this again will tend to instability. As a result of the instability so produced the nebula will change its form, and become more or less pear-shaped. The narrow end of the pear will then separate from the body and assume an independent existence as a primitive planet. This process will recur again and again till the nebula is resolved into a sun with its attendant planets. The planets, existing at first as gaseous masses or quasi-gaseous masses, will be liable to the same kind of transformation, and may thus bud off moons or satellites. If the nebula were not in rapid rotation, a slight disturbing cause, acting at the critical moment when a planet was being ejected, might determine the inclination of the planet’s orbit, which might thus be very oblique to the equatorial plane of the nebula. Thus the hypothesis is not open to one of the objections which have been urged against that of Laplace--namely, that the orbits of some of the planets in the solar system are inclined at a large angle with the plane of the sun’s equator. This illustrates Laplace’s theory, which conceived of a vast nebula filling the whole space of the solar system and rotating around a central axis. The outer and thinner part had much greater movement than the denser central mass, finally being thrown off as a ring, which in turn rolled up into a ball, still following the same course as the ring had followed. Thus the earth broke off from the sun and the moon from the earth. The theory is, however, no longer credited by scientists. The pear-shaped nebula is the theory of a young English mathematician, Professor J. H. Jeans. Starting with a spherical nebula, he argues that in cooling it will assume the form illustrated above, and that the smaller part will separate and form a satellite rotating independently but within a distance influenced by the parent mass. The spiral nebula in Canes Venatici, a revolving mass of gas or meteorites, supplies, according to the nebular hypothesis of Messrs. Chamberlin and Moulton, an excellent example of how the earth and moon were formed. We may reasonably imagine the smaller spiral to represent the moon in the act of being thrown off by the earth. THREE FAMOUS THEORIES OF THE BEGINNING OF THE EARTH] [Sidenote: Heavenly Bodies in Collision] Jeans mentions two disturbing causes in particular which might easily arise--one the penetration of the nebula by a wandering meteorite, which might precipitate an event already on the verge of happening, and simultaneously determine both the birth of a planet and the obliquity of its orbit; the second, the presence of some distant mass, such as a star, which, by raising a quasi-tide in the nebula, would give the final touch required to overturn its equilibrium. The influence of a distant body, such as a passing star, has been invoked by Moulton in another version of the nebular hypothesis. In conjunction with Chamberlin, he calls special attention to the spiral nebulæ, which are by far the commonest kind, as presenting the closest approach to the conditions which obtain when planets are actually in course of formation. Chamberlin and Moulton enter on a detailed account of the manner in which they suppose the planets to have grown by the gradual accretion of meteoric masses as these encountered each other while moving in various elliptical orbits. At present it would seem impossible to speak with certainty as to the precise history of the solar system. Meanwhile, we may console ourselves with the closing words of Professor Jeans’ paper, to the effect that “no difficulty need be experienced in referring existing planetary systems to a nebulous or meteoric origin on the ground that the configurations of these systems are not such as could have originated out of a rotating mass of liquid.” An investigation by Sir George Darwin, which has furnished inspiration to such hypotheses as that of Jeans, brings us nearer the immediate subject of this essay, since it treats of one of the last acts in the great drama of planetary existence, and attempts to derive the earth and moon from a common origin in a single rotating sphere. [Sidenote: Why the Day is Growing Longer] It is well known that, owing to the frictional effects produced by the tides, the earth is being gradually slowed down as it rotates upon its axis. Thus the day is constantly getting longer, so that in a few millions of years it will have increased in length from twenty-four to twenty-five hours. On the other hand, in past time it must have been shorter than at present: a few millions of years ago it was only twenty-three hours in length, and many millions of years earlier it was still less, only some five hours or so. At that time the earth was hotter than it is now, less rigid, more yielding, and, owing to its rapid rotation, less stable. The action on the moon of the tides produced in it by the earth is similar, and the rotation of the moon has been so far diminished by them that its day has become as long as the month--_i.e._, our satellite only turns once round on its axis in the time that it takes to revolve once round the earth; it is for this reason that our satellite keeps always the same face turned towards us. [Sidenote: The Moon Was Part of Our Sphere] The retardation of the earth in its rotation has, however, a very remarkable effect on the revolution of the moon; it involves--by the principle of the conservation of moment of momentum--a corresponding acceleration of the moon in its orbit, and, as a consequence of this, an enlargement of this orbit--that is, the moon is pushed away from us, as it were, and thus becomes more remote. But if so, the moon must have been nearer to us in times past. It is possible to trace the approach of the moon to the earth as we go backwards in time till the distance between them was only two and a half terrestrial radii instead of the sixty radii which now separate them. Mathematics do not take us farther back than this. But it is difficult to resist the suggestion that in the immediately preceding stage of development the earth and moon formed together a single sphere. If we may adopt this view, then we must regard the sphere as subject to the tidal influence of the sun. It was much hotter, and therefore more yielding, than the present earth; it was also rotating much faster, probably once in about four or five hours. It would be contracting as a consequence of cooling, and the contraction would lead to instability (gravitational instability); its rapid rotation would also tend toward instability (rotational instability). It is difficult to say which of these two, gravitational or rotational instability, would be the most effective; but the combined result would be to give a pear-shaped form to the rotating mass, and eventually to deepen the constriction between the narrow and the broad end, till the smaller protuberance became completely dissevered from the larger mass, and so entered on an independent existence as the moon. This final step in the process would probably depend on the tide-producing power of the sun; the larger mass remained behind as the earth, whose individual existence may be said to date from this event. [Sidenote: How the Moon Broke Away] The young earth would be subject to very much the same conditions after as before the ejection of the moon, and might very possibly again pass into a pear-shaped form, but without proceeding further through those subsequent changes, which would have led to the formation of another satellite; and while possessing some such form as this, she might very well have consolidated. With advancing years she would lose, as we have seen, the activity of her youth, the drag of the tides would cause her to spin ever more slowly on her axis, till the day would become prolonged to the twenty-four hours of the present. With this diminished rate of spin, the earth, if free to yield, would lose the pear-shaped form and become an oblate spheroid, and the oblateness of this spheroid would continually diminish, so that it would continually approach towards a true sphere. Suppose, however, that the earth as it cooled lost its power of readily yielding--and at present it is more rigid than a globe of steel--then it would pass from form to form, not by a flowing movement, but by a series of ruptures, and its form at any moment might be a little in arrear of that which it would have possessed if it had been in the fluid state. Thus it might indeed be possible still to discover some trace of an old-fashioned form in the existing planet; and a careful examination of the distribution of land and sea as represented on a terrestrial globe does, in fact, reveal a remarkable symmetry, in which we seem to recognise a surviving vestige of its early state. The great continent of Africa projects like the narrow end of a pear; around it are oceans--the Atlantic, the Indian Ocean, and the Mediterranean Sea, which was once of far greater extent; then comes a great dismembered ring of land, the two Americas, the Antarctic continent, Australia, Asia, and Europe. Within these, on the side opposite to Africa, is the great Pacific Ocean, which covers over the broad end of the pear. [Sidenote: Earth’s Unknown Changes] [Illustration: THE SHAPING OF THE FACE OF THE EARTH Soon after the earth had cooled down, so that the oceans were formed, the shaping of the great continents began. The action of moving water in the making of new land is well illustrated by the vast delta of the Mississippi, where an area larger than Wales has been formed by debris deposited by the river. ] A line drawn from somewhere in Central Africa to its antipodes in the Pacific, through the centre of the earth, would correspond to the long axis of the pear; a second, at right angles to this, would correspond to its breadth; and a third, at right angles to both, would correspond to the axis on which it rotates. A diameter of the earth taken through the equator is almost 8,000 miles in length, the Polar diameter is about sixteen miles shorter, and this slight difference measures the oblateness of the spheroid, or the departure of the form of the earth from a true sphere. Further, it would appear that the diameter drawn through Africa is about half a mile longer than the equatorial diameter taken at right angles to it, and this insignificant quantity measures the departure of the form of the earth from that of an oblate spheroid to that of a pear, so nearly complete is the adjustment of its form to existing conditions. Before this nice adjustment was reached, the earth must have suffered many changes, passed through many times of stress and storm, and witnessed many geological revolutions. [Sidenote: An Age of Red-hot Rain!] If, at the beginning of her career, the earth was molten, or at a very high temperature, she must have been surrounded by a very deep and dense atmosphere, for all the waters which now rest on her surface--oceans, lakes, and rivers--would have contributed to it in the state of steam; and not till the temperature of the ground had fallen to 380 deg. C. could liquid water have begun to accumulate. Then a steady downpour of almost red-hot rain would have set in, filling up the neck of the pear and extending far and wide over its broad end. The temperature would now fall somewhat rapidly, and in a short space of time the surface of the earth would have become as cool as it is at the present day. Directly the waters of the firmament had collected into the oceans, leaving behind an atmosphere like that which now exists, geological agencies of the kind we are now familiar with would begin their sway. Air and rain would exert their insidious power upon the rocks, sapping their strength, converting the hardest granite into soft sand and clay, which would be washed away by the rain through brooks and rivulets into the channels of many rivers, all hastening with their burden of sediment, to deposit it finally in the sea. Here it would accumulate, layer after layer, building up those mighty masses of strata which now form the greater part of the visible land. While this general action was everywhere in progress, wearing down continents and islands towards the level of the sea, more specialised activities were assisting to the same end. [Illustration: TWO STAGES IN THE LIFE OF THE EARTH This illustrates in striking manner, based on the calculations of the best authorities, the comparative sizes of the earth, first as a gaseous mass, and, second, after it had cooled down and solidified into the planet on which we live. The small dot represents 8,000 miles, the earth’s diameter. ] The waves which fall upon our coasts are now constantly undermining the cliffs and extending the margin of the sea at the expense of the land, and rivers not only serve to transport sediment, but cut down their channels deep into the rock, and so carve out the most varied landscapes of hill and valley from monotonous tableland. [Sidenote: Action of Winds and Tides] When we enter into calculations we are astonished at the rapidity with which these agents perform their work even at the present day; but as we proceed farther back into the past, when the earth was full of youthful energy, their power must have been greatly enhanced. We might almost take the measure of the day as the measure of their work, for they probably accomplished as much during the eight hours’ day which once existed as they do now in twenty-four hours. A little consideration will make this clear. It is the winds which, blowing over the surface of the ocean, produce the sea waves, and it is these falling on our coasts that perform the work of marine denudation. But the winds are due in the first place to the heat of the sun, and the difference of temperature established at the equator and the poles; and, in the next place, to the rotation of the earth. Thus, with the increased rapidity of rotation which we know to have existed, and with increased radiation from the sun, a very probable contingency, the winds would increase in strength and more powerfully erode our coasts. Again, with the moon in greater proximity, and with a more rapid rotation of the earth, the tides would be much higher and more frequent, and these, raising and lowering the cutting edge of the sea, greatly assist it in its work of destruction. The winds and the tides produce various marine currents, and these help to distribute the sediment which the rivers deliver into the sea, so that when stronger currents flowed as a result of more powerful tides and more violent winds, the sediments would be strewn over wider areas; hence, the more ancient strata of our planet are far more widely distributed than are those of later time. [Illustration: THREE VIEWS OF THE GLOBE SHOWING HOW THE GREAT MOUNTAIN RANGES WERE FORMED In the days when the earth’s crust had formed but was still unstable, the process of cooling not having gone far enough, there would not be the mountains which now characterise it. These came when the earth contracted and crumpled up along certain well defined lines, which are now represented by the three great mountain chains of the world. ] [Sidenote: Building Up the Earth] Finally, a heavier rainfall would result from a more active atmospheric circulation, creating larger rivers, and thus, at the beginning, all those denuding agents which are engaged in wearing the land down into the sea would be working at a more rapid pace. Correspondingly, all the agents which are occupied in building up deposits of sediments would have extended their operations over a wider area, laying down a foundation broad and deep. On the other hand, the contraction of the earth, due to the loss of its energy of rotation as well as of its internal heat, would also have proceeded more rapidly, new land would have emerged from the sea, old lands would have been submerged beneath it far less slowly than at the present day; ruptures of the crust, accompanied by earthquakes and volcanic action, would have been more frequent and thus, by the more rapid loss of its intrinsic energy, the renovation of the earth would have kept pace with its accelerated destruction. One effect of the contraction of the earth which has manifested itself in even late geological times is the crumpling up of the terrestrial crust into the sharp folds of mountain chains; but at the beginning this crumpling must have been far more universal and energetic. In this connection it is interesting to observe that the most ancient rocks known to us--the Archæan--never present themselves under any other form than as intensely plicated masses. They originally consisted of lava flows and volcanic ashes, of ancient sediments and limestones, into which subterranean masses of granite and other molten, deep-seated rocks have been injected; but under the intense pressures to which they were subjected after their formation they and the invading granite have entirely lost their original character, and have been metamorphosed into gneisses, schists, and marble, all sharply and closely folded together. In any given district the direction of their folding is maintained with wonderful constancy over great distances. There is no succeeding system of rocks that has been so completely transformed, so universally plicated, as this ancient Archæan complex. In later times we can pass from stratum to stratum of the sedimentary series and read their history almost as we turn over the pages of a book; in the Archæan all are kneaded together into a state of such desperate entanglement as to defy the powers of human ingenuity to unravel them. Thus the line of demarcation between the Archæan and subsequent sedimentary systems is the sharpest and most absolute that is known to us in the history of the earth. It marks the close of our planet’s infancy, the several events of which have passed into oblivion as profound as that of our own forgetfulness of our earliest days. Later events, on the other hand, are recorded in the stratified series with a faithfulness which increases as we approach existing times. [Sidenote: How We Know These Wonders] [Sidenote: The Ocean 100 million Years old!] [Sidenote: The Part Radium may play] A history without dates must seem very unsatisfactory to a historian, and the question will naturally arise whether we can assign any definite time to the various critical events recorded in the evolution of the earth. At present we can only make more or less plausible estimates. Thus, from a consideration of the thickness of the sedimentary crust, and the rate at which sediments are now being deposited, it has been asserted that the interval which separates us from the close of the Archæan era may amount to about twenty-six millions of years. Professor Joly, basing his argument on the undoubted fact that the ocean derives the greater part of its salt from the dissolved material contributed to it by rivers, comes to the conclusion that the ocean first came into existence about one hundred millions of years ago. As regards the birth of the moon, Sir George Darwin has given a minimum limit of fifty-four millions of years, but he adds that it may have taken place many hundreds of millions of years before this. Lord Kelvin has attempted to determine the time which has elapsed since the earth first acquired a solid crust. If we only knew the rate at which the earth is cooling we might calculate back to this time with some assurance of certainty, always, however, on the assumption that the earth is simply a hot body cooling like any other hot body--such, say, as a red-hot cannonball. But a few years ago it began to be seriously suspected that this assumption was a very doubtful one, for a new element--radium--was discovered in 1898, which possesses the remarkable property of spontaneously liberating heat, and this not in small quantities, but at an astonishing rate. One gramme of radium, for example, gives out enough heat in one hour to raise the temperature of one gramme of water to boiling point; hour after hour, year in, year out, this wonderful substance is setting free the energy it contains, and will continue to do so until, some thousands of years hence, it has exhausted its store. If this element should happen to exist in sufficient quantity within the earth, then the earth could not be said to be cooling just like a piece of hot iron, and the increase of temperature we experience as we descend towards the interior of the earth might possibly be due to the heat set free from radium. Indeed, the argument is not confined to the earth; it may apply also to the sun, and much of the heat we derive from that luminary may be provided by bursting atoms of radium. This was pointed out by Sir George Darwin and Professor Joly in 1903. It became obviously a question of the first importance to discover what proportion of the earth’s crust consists of radium, and an investigation was undertaken for this purpose by the Hon. R. J. Strutt, who finds that the rocks composing the earth’s crust contain a superabundance of radium--sufficient, if this element is uniformly distributed through the whole earth in the same proportion as it occurs at the surface, not only to make good the heat which is radiated away into space, but actually to raise the temperature of our planet, which, on this evidence, should, therefore, be growing not colder, but hotter. This is a result as disconcerting at first sight as it is astonishing, and its effects are very wide-reaching. Of course, it completely destroys the validity of Lord Kelvin’s argument, but it also deprives the nebular hypothesis of one of its cherished lines of evidence--a loss which the force of the general argument enables us to bear with equanimity. [Sidenote: On the Eve of great Events] In any case, the vast body of facts bearing on the history of the earth suffices to show that its temperature cannot be rising. Mr. Strutt has, therefore, imagined that the radium is not uniformly distributed throughout the mass of the planet, and supposes that it is restricted to an external zone forty-five miles in thickness; this would suffice to maintain the earth at its existing temperature. If, however, we admit a restriction of this kind, we are in no way bound to fix the limit at forty-five miles. All we can say is that we do not know how far downwards the radium reaches--for aught we know five miles, or even less, is as likely a limit as forty-five miles. Professor Joly, indeed, maintains that the radium we meet with is not proper to the earth at all, but comes from the sun. Radium is a short-lived element, its existence being limited to a few thousand years; but as fast as it decays it is reproduced at the expense of another element--uranium--the lifetime of which is measured by hundreds of millions of years. The last quarter of a century has proved fertile in great discoveries--more so than any corresponding period in the past. As a result, the whole world of scientific thought has been thrown into commotion; old-established theories, and even the most fundamental notions, seem to be in a state of flux. Under the stimulus of new ideas great questions, such as the constitution of matter, the origin of species, and the birth of worlds are being re-investigated with renewed energy, and we seem to be on the eve of great events. WILLIAM JOHNSON SOLLAS FOUR PERIODS OF THE EARTH’S DEVELOPMENT A Postscript to Professor Sollas’s Chapter on the Wonderful Story of the World’s Birth, beginning on page 79 The earth was once “a fluid haze of light.” The whole solar system once formed a vast nebula, consisting of glowing gas, or a swarm of meteoroids. Our planet was slowly shaped into a globe out of this primitive nebula. This globe was at first intensely hot, and probably liquid. A solid crust formed on the surface as heat was lost by radiation, and this crust consisted of the oldest rocks of igneous formation like the granites and gneisses. During this Archæan or Eozoic Period, the earth acquired its atmosphere and its oceans, and it is probable that the mysterious origin of life took place. The later history of the earth since the stratified rocks began to appear, and life existed, is divided into four main periods, of which the first is known as Primary, or Palæozoic. The First Period of the Earth CAMBRIAN SYSTEM. The rocks formed in the Cambrian Age are mainly grits, quartzites, and conglomerates, with shales, schists, and limestones. The earth was then mostly covered by seas, and the first well-defined forms of life were of marine origin. SILURIAN SYSTEM. The Silurian rocks are mostly sandstones, shales, and slates deposited in the seas. The first vertebrates made their appearance as fishes, whilst insects began to flutter in the air, and occasionally to alight on the emerging land. DEVONIAN SYSTEM. This was the age of the old red sandstone. Fishes reached a high state of development, whilst the first traces appeared of land vegetation, ferns and lycopods. CARBONIFEROUS SYSTEM. This system is exceptionally important, because its chief rock is coal, the fossilised remains of the luxuriant vegetation which grew in tropical swamps. The first terrestrial animals, true air breathers, now appeared. PERMIAN SYSTEM. The last of the primary systems gave us the new red sandstone, distinguished from the old by lying above the coal measures. The Permian Age was apparently unfavourable to life, and is only notable for the first appearance of the land reptiles into which the amphibians developed. The Second Period of the Earth The Secondary Period marks the emergence of the dry land into importance greater than that of the sea. TRIASSIC SYSTEM. The Triassic rocks chiefly consist of sandstones and hardened clays laid down in shallow sea basins. Land vegetation now first began to assume a modern type, with conifers and cycads. The seas were still richly peopled, and the land first gave a home to huge reptiles, or dinosaurs. JURASSIC SYSTEM. This system is marked by a great variety of limestones, the product of dead sea creatures. It is essentially the age of reptiles. The ichthyosaurus disputed the seas with the plesiosaurus; the pterodactyl ruled the air; whilst on land, huge monsters like the brontosaur and diplodocus browsed on tropical vegetation. From these reptiles the birds were developing, whilst small marsupials, the oldest of the great mammalian race, skipped under the branches. CRETACEOUS SYSTEM. This was the age of the great chalk deposits. The birds, now emerging from their reptilian ancestry, dominated its life, and the first modern plants appeared on the land. The Third Period of the Earth The Tertiary Period marks the true beginning of modern geological history, when the great outlines of geography were laid down, and the first representatives of modern plants and animals made their appearance. EOCENE SYSTEM. The Eocene rocks are mainly limestones, with sandstone and hardened clays. We owe them to the sea and its organisms. Modern evergreen trees now first appeared. The mammals come to the front, with the tapir-like palæotherium and the first recognisable ancestor of the horse. MIOCENE SYSTEM. The Miocene Age was a mountain-building period, when the great chain which runs from the Alps into Central Asia received its final uplift. Deciduous trees, like the beech and elm, now made their appearance. The giant mastodon and the formidable sabre-toothed tiger roamed the Miocene forest, and true apes--man’s first forerunners--mopped and mowed in the boughs. PLIOCENE SYSTEM. The last of the Tertiary ages set the final stamp on the geological moulding of the earth’s crust. Its plants were transitional to the flora of modern Europe. Great herds of herbivora now appeared. The Fourth Period of the Earth The Quaternary Period is that in which we are still living. Its outstanding feature is the appearance of man. PLEISTOCENE OR GLACIAL SYSTEM. Its essential feature was the appearance of glacial conditions over most of the northern hemisphere, when great ice sheets rubbed our land into shape. The vegetation was Arctic, and only animals like the reindeer and the hairy mammoth could endure the cold. HUMAN OR RECENT SYSTEM. The precise antiquity of man is still uncertain, but it was only after the close of the Glacial Period that he made his home in Europe, where he shared a precarious existence with mammoth, cave-bear, and rhinoceros. Man developed through the _Palæolithic_ and _Neolithic_ ages of stone implements to the _Bronze_ and _Iron_ ages, when metal was first worked. In the last of these we live. GEOLOGICAL CLOCK OF THE WORLD’S LIFE This page is an effort, based on Professor Lester Ward’s calculations in “Pure Sociology,” to show the comparative length of each geological period, and the thin white line between Tertiary and Archæan indicates the period of human history. Thin as this line is--and we could not show it thinner--it is too thick, and out of proportion to the rest of the clock. If we assume that from the beginning of the world--from its first forming into a solid sphere--to the present, time may be represented by a day of twenty-four hours, the time occupied by human history does not exceed twelve seconds. This is reckoning human history as ten thousand years. There is, of course, no possibility of obtaining more than relative figures for such a scheme as this, which should be regarded in connection with the previous page and the chart of the Beginnings of Life, facing page 96 [Illustration: The thin white line between the Tertiary and the Archæan periods represents the duration of human history] TABLE SHOWING PROPORTIONS OF YEARS AND HOURS Geological Periods \| Years \| Hours ------------------------+-------------+--------- Archæan \| 18,000,000 \| 6 Laurentian \| 18,000,000 \| 6 Cambrian \| 6,000,000 \| 2 Silurian \| 6,000,000 \| 2 Devonian \| 6,000,000 \| 2 Carboniferous \| 6,000,000 \| 2 Triassic \| 3,000,000 \| 1 Jurassic \| 3,000,000 \| 1 Cretaceous \| 3,000,000 \| 1 Tertiary and Quaternary \| 3,000,000 \| 1 ------------------------+-------------+--------- The Quaternary Period \| 72,000,000 = 24 is that in which we live\| TERTIARY AND QUATERNARY PERIODS At a rough guess, three million years may be allowed for the Tertiary and Quaternary periods --------------------+-----------+------+------+------ Geological Periods \| Years \| Hrs. \| Min. \| Sec. --------------------+-----------+------+------+------ Tertiary \| 2,600,000 \| -- \| 52 \| -- Pleistocene \| 300,000 \| -- \| 6 \| -- Human \| 100,000 \| -- \| 2 \| -- +-----------+------+------+------ Total \| 3,000,000 \| 1 \| -- \| -- --------------------+-----------+------+------+------ Human History \| 10,000 == == 12 HOW LIFE BECAME POSSIBLE ON THE EARTH BY DR. ALFRED RUSSEL WALLACE Early writers on the relation of man and animated nature to the material universe not only assumed that the latter existed for the former, but that both alike were the results of special acts of creation. Furthermore, they usually took it for granted that all things were created very much in the condition in which we now see them, and that any changes that have since taken place are but slight superficial modifications of a permanent and unchanging whole. Not only were the sun and moon and stars created as appanages of the earth, but the earth itself in all its details of sea and land, hills and valleys, mountains and precipices, swamps and deserts, was made and fashioned just as we now see it, and every feature of its surface was supposed to have some purpose in connection with man. [Sidenote: The Old Ideas of Creation] These purposes we could, in some cases, understand, while in others they seemed wholly unintelligible, and much ingenuity was bestowed by the natural theologian and others to explain more and more of the observed facts from this point of view. The same opinions prevailed in regard to the infinite variety of animals and plants, each individual species being supposed to have been an independent creation, and all to have some definite and preordained purpose in relation to mankind. These views, however absurd they seem to most people now, were almost universally held so recently as during the seventeenth and eighteenth centuries, and were thus coincident with one of the most brilliant epochs of our literature and our dawning science. It was only towards the beginning of the nineteenth century, when geology became widely studied and its results were fully appreciated, that the more rational conception of a very slow development of the earth’s surface during countless ages began to be generally accepted. [Sidenote: Changing Conditions of the Earth] The grand nebular hypothesis of Laplace came to reinforce the views of the geologists, by showing how the earth itself may have originated as a gaseous or molten globe; and its slow process of cooling, with the reaction of the interior and exterior on each other, served to elucidate the facts of the heated interior, as shown by hot springs and volcanoes, as well as many of the phenomena presented by the distorted and metamorphosed strata which formed its crust. Hence it gradually came to be perceived that the condition of the earth, with all its endless variations of surface, of continents and oceans, of seas and islands, of vast plateaux and lofty mountain ranges and extensive low plains, with their ravines and cataracts, their great lakes and stately rivers, was subject to perpetual change from that remote epoch when it seems to have been actually the case that “the earth was without form and void,” and that owing to the greater density of the vapour-laden atmosphere, “darkness was upon the face of the deep.” [Sidenote: Changing Forms of Life] Another field of geological research forced us to the conclusion that the same continued process of change had affected the forms of life upon the earth. When carefully investigated, the crust was found to abound in the fossilised remains of animals and plants. Careful study of these showed that the oldest of all were of comparatively simple structure, and that the higher forms only appeared in more recent epochs; while the highest of all were probably very little older than man himself. It is only during the last half century that the theory of Evolution has been elaborated and has become generally accepted as applicable to the whole of the vast cosmic process--from the development of the nebulæ into stars and suns and systems, with a corresponding development of planets from an early condition of intense heat, through a more or less lengthy period of cooling and contraction, to an ultimate state of refrigeration, the earlier and later stages being alike unsuited to the existence of life. [Sidenote: Theory of Natural Selection] More important still, the discovery of the theory of Natural Selection by Darwin--and at a later period by myself--has led to a satisfactory explanation of the successive appearance of higher and more complex forms of life, and also of that wonderfully minute and complex _adaptation_ of every species to its conditions of existence and to its organic as well as its inorganic environment, which all other theories--even the most recent--have failed to grapple with. [Sidenote: Wonderful Complexity of the Universe] The logical completeness as well as the extreme simplicity of this explanation of organic evolution has led great numbers of thoughtful but ill-informed persons to reject it, because it seems to render unnecessary the existence of a primary intelligent cause; while another equally large but, as I think, equally ill-informed class--the so-called monists--use it to demonstrate the non-existence, or, at all events, the needlessness, of any such cause. Both alike err, because they fail to take cognisance of the fact that every form of evolution, and pre-eminently that of the organic world, is an explanation of a process of change, a law of development, not in any sense or by any possibility an explanation of fundamental laws, causes, or origins. It presupposes the existence not only of matter--itself a thing whose nature is becoming more and more mysterious and unthinkable with the advance of physical science--but of all the vast complex of laws and forces which act upon it--mechanical, physical, chemical, and electrical laws and forces--all more or less dependent on the still more mysterious, all-pervading ether. Thus, the universe in its purely physical and inorganic aspect is now seen to be such an overwhelmingly complex organism as to suggest to most minds some vast intelligent power pervading and sustaining it. Persons to whom this seems a logical necessity will not be much disturbed by the dilemma of the agnostics--that, however wonderful the material universe may be, a being who could bring it into existence must be more wonderful, and that they prefer to hold the lesser marvel to be self-existent rather than the greater. When, however, we pass from the inorganic to the organic world, governed by a new set of laws, and apparently by some regulating and controlling forces altogether distinct from those at work in inorganic nature; and when, further, we see that these organisms originated at some definite epoch when the earth had become adapted to sustain them, and thereafter developed into two great branches of non-sentient and sentient life, the latter gradually acquiring higher and higher senses and faculties till it culminated in man--a being whose higher intellectual and moral nature seems adapted for, even to call for, indefinite development--this logical necessity for some higher intelligence to which he himself owes his existence, and which alone rendered the origin of sentient life possible, will seem still more irresistible. [Sidenote: Mind Behind the World] The preceding remarks are intended to suggest that the theory of evolution, combined with the quite recent and very startling advances in physical science, so far from making the universe around us more intelligible as a self-sustaining and self-existent whole, has really rendered it less so, by showing that it is infinitely more complex than we had formerly supposed; and further, that matter itself, instead of being, as was once believed, a comparatively simple thing, eternal and indestructible, is in all its various forms subject to decay and disintegration. We now see that the only thing known to us that we can conceive as having unending existence is mind itself; and, just as Darwin’s theory of Natural Selection has opened up to us an infinite field of study and admiration in the forms and colours and mutual relations of the various species of animals and plants, so does modern science open up to us new and unfathomable depths in the inner structure of matter and of the cosmos, and thus compels us more and more to recognise a mental rather than a mere physical substratum to account for its existence. There is, however, another set of relations which have been hitherto very little studied--those between the organic and the inorganic worlds in their broader aspects. These are now found to be very much more complex and more remarkable than is usually supposed, and they also have an important bearing upon the great problem of the origin and destiny of man. This is a subject which opens up a variety of considerations of extreme interest, showing that the exact adaptations of our earth--and presumably of any other planets--to enable it to sustain organic life, from its first appearance and through its long course of development, is as varied and complex and as much beyond the possibilities of chance coincidences as are any of the individual adaptations of animals and plants to their immediate environment. Most of these latter adaptations have been made known to us by Darwin and his followers, and they have excited the admiration and astonishment of all lovers of Nature. When the antecedent and grander relations of planet to life are studied with equal care, these also will, I believe, excite deeper admiration, still more profound astonishment, because any secondary laws that could have brought them about are less easy to discover, or even to imagine. [Sidenote: Essential Conditions of Life] Before we can form any adequate idea of the nature of a world which shall be able to support and develop organic life, we must consider what are the special conditions that alone render such life possible. We, of course, refer to the whole of the organic world, from the lowest to the highest, not to the few exceptional cases in which life may be possible under conditions that would be fatal to the higher as well as to most of the lower forms. [Sidenote: The Miracle of Human Life] The one striking speciality of the higher animals--and to a less degree of the higher plants--is that of continuous, all-pervading motion, every portion of their substance being in a state of flux: each particle itself moving, growing, living and dying, and being replaced by other particles of the same nature and fulfilling the same functions. To keep up this growth, and to enable every part of the structure to be continually renewed, food is required. This is taken into the stomach of animals in the solid or liquid form, is then decomposed and recomposed, that which is useless or superfluous being thrown off by the intestines, while what is needed for growth is transformed into blood and by a wonderfully intricate system of branching tubes is carried to every part of the body, furnishing nourishment and repair alike to bone and muscle, to all the internal organs and all the outward integuments, and to that marvellously complex nervous system which also permeates every part of the body and is essential to the higher manifestations of life--to the exertion of force, voluntary motion, and, apparently, to thought itself. Add to this the constant influx of air, which at once purifies the blood and supplies animal heat, and is so important that its cessation for a few minutes is usually fatal, and we have a machine so complex in its structure and mode of action that the most elaborate of human machines is but as a grain of sand to a world in comparison. [Sidenote: Basis of Physical Life] Now the very possibility of such a material organism as this depends upon a highly complex form of matter termed protoplasm, which is at once extremely plastic and of extreme instability, and is yet capable of secreting or building up its atoms into such solid and apparently durable forms as bone, horn, and hair, besides the various liquids and semi-solids which build up the organism. This fundamental organic substance consists of only four chemical elements--nitrogen, hydrogen, oxygen and carbon, and almost all animal and vegetable structures and products have the same elemental constitution, though with such widely different characteristics. Four other elements--sulphur, lime, silicon, and phosphorus--also occur in small quantities in organic tissues, to supply special needs; but these are not essential to all forms of life, and are only taken up and utilised by the living protoplasm when required. Protoplasm is undoubtedly the basis of physical life, yet it only exists in, and is produced by, living organisms. The moment such an organism dies, disorganisation and decay set in, and the whole mass becomes gradually changed into more stable compounds, or into its constituent elements. It appears, therefore, that some agency--usually termed “vital force”--must be at work, first to produce this wonderful compound, then to form it into “cells”--the physiological units of all organisms--and afterwards to direct the energies supplied by heat and light so as to build up the excessively complex structures, with all their wonderful powers and potentialities, which we term animals and plants. All this seems to imply not “a force” only, but very many forces, all of which must have some kind of mind in or behind them, to direct these forces to such infinitely varied yet perfectly defined ends. [Sidenote: A Marvel of Every Day] Consider for a moment one of the simplest of these cases. Let us take the minute seed of one of the great tropical fig-trees, and another seed of a strawberry, or of garden cress. Both will be about the same size and shape, and the most acute microscopist would not find any difference in the internal structure that could intelligibly account for the different results when these little grains of protoplasm are exposed to identical conditions. For, even if planted near each other, and exposed to the same amount of heat and moisture, to the very same atmosphere, and the same kind of water, as well as identically the same soil, yet invariably the one will grow into a large tree, the other into a small herb, and in the course of time, still with no change whatever of the physical conditions to which both are exposed, each will produce its peculiar foliage, and flowers, and fruit, very different in all their characters from those of the other. Were this result not so common as to seem to us “natural,” we should call it a miracle; and it is really and essentially as inexplicable as many things which are termed miracles only because they are unfamiliar and inexplicable. Now, this wonderful substance, the physical base of all life--and as it is the only base that exists, or has ever existed, on the earth, we may fairly assume that no other is possible--can only maintain itself and perform its functions under certain very definite conditions, which conditions are now maintained on our earth’s surface, and must have been maintained throughout the long geological periods during which life has been slowly developing. What these conditions are we will now proceed to show. [Sidenote: The First Essential for Life] The first essential for organic life is a certain very limited range of temperature. We are so accustomed to consider the change of temperature from winter to summer, from day to night, and that which occurs when we pass from the tropics to the Polar regions as being very great, that we do not realise what a small proportion such changes bear to the whole range of temperature that exists in the known universe. The absolute zero of temperature is calculated to be minus 461° F., while the heat of the sun has been determined to be over 10,000° F., and many of the stars are known to be much hotter than the sun. The actual range of temperature is therefore enormous; but any development of organic life is possible only within the very narrow limits of the freezing and boiling points of water, since within those temperatures only is the existence of liquid water possible. But a much less range than this is really required, because albumen, one of the commonest forms of protoplasm, is coagulated or solidified at a temperature of about 160° F. Now, if, as is generally believed, the earth has been once a liquid or even a gaseous mass and has since cooled to its present temperature on the surface, and the sun is undergoing a similar process of cooling, we are able to understand that the very limited range of temperature within which life development is possible implies an equally limited period of time as compared with that occupied by the whole process of solar and planetary development. [Sidenote: We Live by the Heat of the Sun] It must be understood, however, that the present temperature of the earth’s surface is due entirely to sun-heat, and that if that were withdrawn or greatly diminished the whole surface of the globe would be permanently far below the freezing point and all the oceans be frozen for a considerable depth; so that all organic life would become extinct. Under such conditions no renewed development of life would be possible; and it is therefore quite certain that the sun has actually maintained the uniform moderate temperature required, and must continue to maintain it for whatever future period man is destined to continue his existence upon the earth. But it is not only a certain amount of heat that is required, but also a sufficient quantity of light; and this implies a further restriction of conditions, because light is due to vibrations of a limited range of wave-length, and without these particular rays plants cannot take the carbon from the carbonic acid in the atmosphere, and by its means build up the wonderful series of carbon compounds, including protoplasm, which are essential for the life of animals. What is commonly termed dark heat, therefore, would not be sufficient for the development of any but the lowest forms of life, even though it produced the necessary temperature during a sufficient period of time. All organisms, from the lowest to the highest, whether plant or animal, consist very largely of water, and its constant presence either in the liquid or gaseous form is essential for organic life. On our earth oceans and seas occupy the greater part of the surface, while their average depth is so great that the quantity of water is sufficient to cover the whole of the globe free from inequalities two miles deep. It is this enormous amount of water that supplies the air with ample moisture, such as renders the life of the tropics so luxuriant. Yet even now the inequality of water-supply is such that large areas in all parts of the earth are what we term deserts, only supporting a very few forms of life that have become specially adapted to them, and certainly unfitted for the continuous development of life from lower to higher forms. [Sidenote: Water and the Atmosphere] Water is also of immense importance as an equaliser of temperature, the currents of the ocean conveying the warmth of the tropics to ameliorate the severity of temperate and Polar regions, while the amount of water-vapour in the atmosphere acts as a retainer of heat during the night, without which it is probable that the surface of the earth would freeze every night even in the tropics. When we consider that water consists of two gases--oxygen and hydrogen--in definite proportions, and that without their presence in these proportions and in the necessary quantity the development of organic life would have been impossible, we find that we have here a remarkable and very complex set of conditions which must be fulfilled in any planet to enable it to develop life. But this is not all. The atmosphere is so intimately associated with water in its life-relations, and is itself so absolutely essential to the existence from moment to moment of the higher animals, that the two require to be duly proportioned to each other and to the globe of which they form a part. [Sidenote: How Water Protects Earth by Night] In the first place the atmosphere must be of a sufficient density, this being needed in order that it may be an adequate storer up of solar heat, and also in order that it may be able to supply sufficient oxygen, water-vapour, and carbonic-acid gas for the requirements of both vegetable and animal life. We have a striking example of the use of air as a storer-up and distributor of heat and moisture in the very different character of our south-west and north-east winds. The effect of the density of the air is equally well shown when we ascend lofty mountains where we find perpetual snow and ice, due simply to the fact that the air is not dense enough to retain the heat of the sun--which is actually greater than at low levels--so that at night the temperature regularly falls below the freezing point. On the other hand a very much denser atmosphere would absorb so much water vapour as probably to shut out the light of the sun, and thus have a prejudicial effect on vegetable life. Again, there is good reason to believe that the proportions of the various gases in the atmosphere are, within certain narrow limits, such as are most favourable not only for the life that actually exists, but for any life that could be developed from the elements that constitute the universe. Oxygen has properties which seem absolutely essential to organic life; but nitrogen, though only serving to dilute the oxygen so far as the higher animals are directly concerned, is yet indirectly essential for them, since it is in vegetables a constituent of that protoplasm which is the very substance of their bodies. [Sidenote: Use of Thunderstorms] [Sidenote: The Wonder of the Atmosphere] Now, plants obtain their nitrogen mainly from the minute proportion of ammonia that exists in the atmosphere, and this ammonia is formed by the union of the nitrogen of the air with the hydrogen of the water-vapour under the influence of electric discharges--that is, of thunderstorms. It is evident, then, that the required amount of this essential compound will depend upon a due adjustment of the quantities of nitrogen and aqueous vapour always present; while the electric discharges seem to be due to the friction of various strata of air with each other and with the earth’s surface, due to the winds and storms; and winds are due to highly complex causes, involving the rate of the earth’s rotation, the rise and fall of the tide, the density of the atmosphere, the quantity of its aqueous vapour, and the amount of solar heat which it receives. Unless all these very diverse factors existed in their due proportion, some of the results might be highly prejudicial if not quite inimical to the development of life. To these various adaptations of our gaseous envelope we must add one other. Carbonic acid gas in the atmosphere is absolutely essential to vegetable life, while it is directly antagonistic to that of the higher animals. Its quantity must, therefore, be strictly proportionate to the needs of both; and that beneficial proportion must have been preserved throughout the whole period of the existence of the higher air-breathing animals. These various considerations show us that our atmosphere, consisting as it does mainly of two common gases mixed together, and therefore seeming to most people one of the simplest things possible, is really a wonderfully complex arrangement which is adapted to serve the purposes of living organisms in a great variety of ways. But this by no means exhausts the subject of its adaptation to support and develop organic life, because its very existence on the earth in a suitable quantity and composed of the essential elements can be shown to depend on other and deeper relations which will now be pointed out. The older writers on the subject of the habitability of the planets took no account whatever of the importance of size, distance from the sun, period of rotation, and obliquity of the ecliptic as determining the possibility of organic life, but simply assumed that, because the earth possessed an abundant life-development, all the other planets must also possess it. But we know that the above-mentioned factors are of very high importance, as we will proceed briefly to point out. [Sidenote: Earth’s Envelope of Gas] It is now believed that the amount of atmosphere possessed by a planet is due mainly, perhaps entirely, to the planet’s mass, and its consequent gravitative power. Spectrum-analysis has shown that vast masses of gaseous matter exist in the universe, and it is probable that, in a state of extreme tenuity, these are very widely diffused. Just as meteoric dust is constantly attracted to the earth, and periodically in larger quantities, so are gases, and supposing the aggregations of free gaseous matter to have been distributed with some approach to uniformity, then, as planets grew in size, they would also tend to secure a larger amount of the diffused gases, thus forming deeper atmospheres. The observed facts agree with this view. The largest planets, Jupiter and Saturn, have such a depth of atmosphere as permanently to obscure any solid interior they may possess. The only planet closely approaching the earth in size and density--Venus--has an atmosphere which appears to be loftier than ours, but it may be composed of different gases. Mars, which has only one-ninth the mass of the earth, has a lofty but very tenuous atmosphere, and probably no water, the Polar snows being due probably to the freezing of some dense gas. The climate and physical condition of Mars is, however, still a subject of much controversy, which I hope to discuss in a separate work dealing with the arguments of Professor Lowell [see page 105]. In that volume the reader will find, fully set forth my reasons, on scientific grounds, against the supposed habitability of Mars. [Sidenote: The Earth Selects and Uses Gas] But, besides attracting cosmic masses of gaseous matter to form its atmosphere, there is another equally important function of the mass of a planet--its selective power on the kind of gases it can permanently retain in a free state. The molecules of gases are in a condition of rapid motion in all directions, which explains the elastic force they exhibit. The speed of this motion has been determined for all the chief gases, and also the gravitative force necessary to prevent them from continually escaping into space from the upper limit of the atmosphere. Thus the moon, which has a mass only one-eightieth that of the earth, can retain no free gas whatever on its surface. Mars can retain only the very heavy gases, but neither hydrogen nor water-vapour. The earth, however, has force enough to retain all the gases except hydrogen, which is just beyond its limit; and this may explain why it is that there is no free hydrogen in the atmosphere, although this gas is continually produced in small quantities by submarine volcanoes, is emitted sometimes from fissures in volcanic regions, and is a product of decaying vegetation. Once united with oxygen to form water, it becomes amenable to gravity in the form of invisible aqueous vapour, and is thenceforth a permanent possession for us in its most valuable form. [Illustration: EARLY ICE AGE, WHEN MAMMOTHS ROAMED THE EARTH AND MAN WAS ARISING] The very accurate adjustments that render our earth suitable for the production and long-continued development of organic life, culminating in man, may be well shown by another consideration. If our earth had been 9,600 miles instead of 8,000 miles in diameter--a very small increase in view of the immense range of planetary magnitudes from Mercury to Jupiter--with a slight proportionate increase in density, due to its greater force of gravitative compression, its mass would have been about double what it is now. This would probably have led to its having attracted and retained double the amount of gases, in which case the water produced would have been double what it is--perhaps even more, because hydrogen gas would not then escape into space as it does now. But the surface of the globe would have been only one-half greater than at present; so that, unless the ocean cavities were twice as deep as they actually are, the whole surface of the earth--except, perhaps, a few tops of submarine volcanoes--would have been covered several miles deep in water, and all terrestrial life would have been impossible. [Sidenote: The Deep Atmosphere of Venus] From the various considerations here set forth it appears clear to me that no other planet of the solar system makes any approach to the conditions essential for the development of a rich and varied organic life such as adorns our earth. One only--Venus--has a sufficient bulk and density to give it the needful atmosphere; but as it receives about twice as much solar heat as does the earth, it is probable that its very deep atmosphere may be mainly due to the fact that a large proportion of its water is held in a state of vapour, its seas and oceans being proportionately reduced in extent. Judging from what happens on the earth, this would probably lead to an excessive area of deserts, and thus be inimical to life. But this planet appears to possess one feature which renders it fundamentally unsuitable for organic life. [Sidenote: Why there is no Life on Venus] Several modern observers have found that the older astronomers were all in error in giving Venus a rotation-period almost exactly the same as ours, an error due to the indefinite and variable markings of its surface. They have now deduced a period about equal to that of its revolution round the sun--a rate which has been confirmed by spectrum-analysis, and further confirmed by the fact that this planet has no measurable polar compression. As during transits of Venus over the sun’s disc the conditions for the accurate measurement of the compression, if any exist, are the best possible, and as none has been found, this alone affords a demonstration that the rate of rotation must be very slow, because the laws of motion _necessitate_ a definite amount of equatorial protuberance corresponding to that rate. Half the surface has, therefore, perpetual day and the other half perpetual night, leading to violent contrasts of heat and cold for the two hemispheres with, in all probability, correspondingly violent winds, rains, and electrical disturbances--conditions so entirely opposed to the uniformity of temperatures and stability of meteorological phenomena during long geological epochs which are essential for the full development of organic life, that such development is perhaps less probable on this planet than on any other. I think I have now shown not only that no other planet in the solar system makes any approach to the possession of the varied and complex adaptations which are essential for a full development of organic life, but also that on the Earth itself the conditions are so numerous and so nicely balanced that very moderate deviations in excess or defect of what actually exists in the case of any one of them--and of others not referred to here--might have rendered it equally unsuitable, so that either no organic life at all, or only a very low type of life, could have been developed or supported. [Sidenote: There is Purpose in our World] If, then, the more superficial indications of design in the relations of animals to their environment, and of man to the universe, have been shown by modern science to have required no _special_ interference of a higher power to bring them about, but that they have been due to natural laws acting in accordance with and in subordination to the deeper laws and forces that determine the very constitution of matter and the unknown power and principle we term “life,”--yet, on the other hand, we find that a more careful study of the outer universe, or cosmos, reveals a new set of adaptations not less wonderful or more easily explicable by chance coincidence than those presented by the organic world. Even the very brief sketch of the subject here given suggests the idea of _purpose_ in a world so precisely and uniquely adapted to develop organic life, and to support that life during the countless ages required for the completed evolution of man. But that suggestion becomes a logical induction when the whole of the available evidence is set forth, as I have attempted to set it forth in my work on “Man’s Place in the Universe.” I have there shown not only that the cumulative evidence for the earth being the only supporter of a fully-developed organic life within the solar system is irresistible, but that there is some direct, and much more indirect, evidence that this uniqueness extends to the whole stellar universe; and it is certain that no particle of _direct_ evidence for the existence of organic life elsewhere has been, or is likely to be, adduced. I have also shown (in an appendix to the second edition of my book) that the purely biological argument for the uniqueness of the development of man--as the culminating point of one line of descent throughout the diverging ramifications of the animal kingdom--is overwhelmingly strong; hence the logical conclusion from the whole of the evidence is that man is the one supreme product of the whole material universe. My object in the present essay has been limited to showing that, besides and beyond the special adaptations of the various kinds of animals and plants to their special environments, there exist in the earth as a planet, in its various physical and cosmical relations, a whole series of adaptations of a very remarkable character which, so far as we can judge, are essential to its function as a life-producing world. The study of these adaptations, therefore, may be considered to be appropriate here, as constituting a preliminary chapter in the natural history of the Earth and of Mankind. ALFRED RUSSEL WALLACE [Illustration: IN THE DAYS OF THE SEA MONSTERS Reproduced from a plate in Hawkins’ “Book of the Great Sea Dragons.” ] THE BEGINNING OF LIFE ON THE EARTH BY DR. C. W. SALEEBY [Sidenote: The Earth Without Life] For some decades past we have been faced with a critical difficulty at the most critical and important point in the history of the earth. In the first place, it has been definitely established that in the earlier period of its history there was no life whatever--as the word is usually understood--upon the earth, as is abundantly shown elsewhere in this work. None of the conditions that make life possible, as we know it, were satisfied. As a recent French writer has said, life is an aquatic phenomenon, absolutely incapable of existence except in the presence of liquid water; and there was an age of vast duration in the history of the earth when all its water must have been in the gaseous state. Other reasons of equal cogency may be at present ignored. The broad fact is that, however widely students of this matter may differ on other points, there is absolute agreement upon the cardinal and initial fact that whereas there is life upon the earth now, there was a time when there was none. [Sidenote: A Gap in the Philosophy of Evolution] Now, in the ever memorable year 1859, Charles Darwin published a volume, the main thesis of which is now universally accepted, wherein the following is the last sentence: “There is grandeur in this view of life, with its several powers, having been originally breathed by the Creator into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being evolved.” “The Origin of Species” may be said, in a word, to establish the doctrine of the evolution of living organisms upon the earth “by laws acting around us”--to use Darwin’s own phrase. But Darwin’s work begins with and assumes the existence of life as an established planetary fact. There obviously remains a tremendous gap in the evolutionary philosophy as it stands in our statement of it thus far; and the first fact which we have to note is that the existence and recognition of this supposed gap, so far from being a matter of common recognition from the earliest times, so far from being an observation made by the critics of the doctrine of evolution, is, on the contrary, a special doctrine peculiar to scientific study and of quite recent origin, being indeed established--as was supposed--within the memory of many now living. If we turn to the first chapter of Genesis, we shall see no suggestion or recognition of the supposed difficulty involved in the beginning of life upon the earth. In this immortal piece of ancient poetry it is stated that after the creation of the heaven and the earth, which were at first “without form and void,” God said, “Let the earth bring forth grass ... and it was so”; and later God said, “Let the waters bring forth abundantly the moving creature that hath life ... let the earth bring forth the living creature after his kind.” Here we have suggested to us the natural origin of living creatures in earth and sea under the will and direction of the Creator as conceived by the poet. [Sidenote: First Ideas on the Origin of Life] [Sidenote: The Coming of Darwin] Partly to the influence of Genesis, partly to the apparent facts of observation, and partly to the views which would naturally be held by poets and thinkers, we may attribute the belief which has been held by man, simple and philosophic alike, since first men began to think, until, we may say, the third quarter of the nineteenth century--the belief that the lowest of living things arose by a natural genesis or so-called spontaneous generation in suitable materials already provided on the land or in the sea. It was not suggested or believed that very large and conspicuous living creatures were thus bred, though it is true that the ancients thought even crocodiles to be generated by the action of the sun upon the slime of the Nile. The living creatures supposed to arise naturally in the womb of earth--the all-mother--were mostly small creatures, like insects and worms. The ordinary belief of the uninstructed to-day--a belief which they share with the greatest thinkers of antiquity and the Renaissance--is that the cheese-mite, for instance, is evolved from the substance of the cheese. Now, it is of particular moment to observe the vast contrast between the significance of this belief prior to the publication of “The Origin of Species” and its significance to-day. Before we accepted the doctrine of organic evolution, the supposed spontaneous origin of the cheese-mite in cheese, or of the maggot in putrid meat, was of no very great moment; a maggot or a cheese-mite is an extremely insignificant object. So far as the great problems of the universe are concerned, a cheese-mite, as we say, is neither “here nor there,” and its spontaneous generation was not regarded as a fact of any great moment. But then there arose Darwin, who, in establishing the doctrine of organic evolution already supported by his own grandfather, by Lamarck, and Goethe, and Herbert Spencer, gave an entirely new importance to the question. He demonstrated how we could conceive the evolution of all organisms, including man, from a “few simple forms,” under the continuous influence of natural law; and thus such forms ceased to be insignificant, and the manner of their genesis came to be a vital problem in more senses than one. Such organisms--the mite, the maggot, and even the mould--could no longer be regarded as insignificant, for they were revealed as not unlike the ancestors of man himself. [Sidenote: Evolution a Continuous Process] The question of the beginning of life upon the earth had only to be satisfactorily answered for the establishment of the belief in a continuous process of evolution by natural law, even from the very beginning of the earth itself “without form and void,” until the production of the highest living organisms which it displays in our own time. And all ages, even by the mouths of their great thinkers and closest observers, had agreed in giving an apparently satisfactory answer to this question. It might well have been thought that Darwin was quite entitled to ignore altogether, as he did, the question of the origin of life. Everyone knew, so to say, that simple living organisms were every day evolved in organic refuse and elsewhere. Darwin himself, if we may judge from a casual remark in a letter, regarded the question apparently as purely speculative, and of small real moment. It is all rubbish, he says, thinking about the origin of life; we might as well argue about the origin of matter. We must beware of illegitimately attributing opinions to the immortal dead, but this remark, though a casual one, does seem to suggest that Darwin regarded these two questions as on all-fours, if not, indeed, as different forms of the same question, and that, if he had actually formulated his views, they would have taken the shape of the doctrine which asserts that life is implicit and potential in matter; in other words, that when suitable conditions arose--such, for instance, as the presence of liquid water--matter would display the properties of life. [Sidenote: An Abyss that could not be Bridged] Now, the remarkable fact--one of the most striking in the history of science--is that the time-honoured belief in spontaneous generation should have been attacked, and attacked with apparent success, just at the very time when it would otherwise have begun to assume real philosophic importance. For ages it had been accepted, taken as a matter of course, and not regarded as having any particular bearing upon the supreme questions. Then there came the time when this belief would have been an all-important link, without which the chain of evolution could not be completed, a link without which we were left to contemplate a perfect chain of inorganic evolution--the history of the earth before life--and a perfect chain of organic evolution--the history of life upon the earth, with an abyss between the two that could not be bridged, for how came life where there was no life? A series of experiments were made, experiments in which, strikingly enough, some of the greatest evolutionists of the day took a leading part, and these seemed to upset, just when it was most wanted by themselves for the establishment of their new doctrine, the belief which had gone without question for so many ages. [Sidenote: Is Life only Self-movement?] Now, some may be inclined to wonder how it should be that certain pioneers of the new doctrine of evolution, such as Tyndall and Huxley, should devote themselves with such persistence and labour and force to the overthrow of a doctrine which was so necessary for the complete establishment of their own case--so much so, that when they had overthrown it, they found themselves, as regards their own doctrine of evolution, placed in a difficulty from which they did not live to emerge. It is my own belief that this question can be answered, and the answer is of strict relevance to our present inquiry. I believe that Huxley and Tyndall were largely impelled by the desire to oppose a doctrine of the nature of life which was current in their time and is usually called “vitalism.” We shall not begin to understand the question of the beginning of life upon the earth, as that question may be legitimately stated to-day, unless we fully realise in what terms the doctrine of spontaneous generation was accepted in the past, and an understanding of this will teach us that the present-day revival of this doctrine presents it in a form very different from that which it so long held. Our discussion must be somewhat philosophic in character, but the question at issue is a highly philosophic one, and the reason why we have made so little progress in answering it hitherto is that men of science have too frequently discussed it without paying any serious attention to the profound philosophic questions which really underlie it. We have permitted ourselves to talk freely about life and matter, whilst claiming the right to take for granted the absolute validity of our conceptions of life and our conceptions of matter. It was universally held by those, philosophic and simple, who also held throughout so many centuries the belief in spontaneous generation, that there is an overwhelming contrast between living and lifeless matter, and it was their belief in this overwhelming contrast that led them to give to the doctrine of spontaneous generation, as they held it, a form which cannot possibly be defended. The great character of life was conceived to be self-movement, this self-movement being displayed in the matter which composed the living organisms. But it was universally held that matter, as it was seen otherwise than in living organisms, was obviously and notoriously inert, gross, brute, and dead. [Sidenote: The Influence of Plato] The great influence of Plato taught men to despise matter in this fashion, and there was the everyday experience that a stone lies where it is placed until something from outside moves it, being, therefore, inert, whilst a living creature such as a bird moves freely at its own will. The more strongly men held the natural matter of which the earth is composed to be inert, the more necessary was it to suppose that when life was displayed in it the difference consisted in the taking possession of this dull clay by a vital force--a mystic and wonderful principle of quickening--which endowed even gross, inert matter with activity and power. From the time of Plato until the last few years of the nineteenth century thinkers vied with one another in insisting upon the impotence and grossness and inertness of matter, and each fresh insistence upon this doctrine rendered more necessary a corresponding doctrine of vital force or vitalism, which should explain the amazing transformation undergone by, let us say, the gross and inert matter composing food, when that food was converted by the “living principle” into the tissue of a living creature, and then displayed self-movement. [Sidenote: Philosophy of Dead Matter] [Sidenote: The Great Work of Pasteur] This doctrine of vitalism, which held sway for so long, was naturally invoked to explain the origin of life upon the earth, when the advance of astronomy and geology demonstrated a natural evolution for the earth and proved that there must have been a time when no life was possible upon it. The prevalent conception of matter came in at this point and denied altogether any such monstrous doctrine as that the wonderful thing called life could spontaneously arise in the despicable thing called matter. The material of the earth, whether solid, liquid or gaseous, consisted of eternal, unchangeable, and indestructible atoms. These were moved as forces from outside moved them. They had no energy or power of their own. Men simply thought of them as of incredibly minute grains of sand of various shapes and sizes, and it was as impossible to conceive of life being spontaneously generated in a chance heap of inert atoms as to conceive that a heap of grains of sand should organise themselves into a little organism. As for spontaneous generation occurring on the earth to-day, the development of mites from cheese and so forth, that was a very different matter, men must have thought--in so far as they thought at all--since cheese and flesh and so forth were themselves products of life. It is well worth noting that the common doctrine of spontaneous generation was always held in reference to organic materials, such as the slime of the Nile--not the dry sand of the desert. The reader may be inclined to say that men’s beliefs on this subject in the past generation make very confused reading, and indeed, that is true. But the fact is that their beliefs were most confused. The work of Darwin had staggered everybody, and straightforward, systematic, unprejudiced thinking was very nearly impossible in the welter of controversy. Nevertheless, something apparently definite was done. The doctrine of the beginning of life upon the earth was left almost undiscussed, and the accepted notion of the nature of matter--a notion which to us who know radium seems puerile--was left unchallenged in all its falsity. But the work of the great French chemist Pasteur led to a close examination of the belief that humble forms of life are daily produced from lifeless organic materials, and the conclusion was reached that no such spontaneous generation occurs. [Sidenote: Every Living Thing from a Living Thing] This conclusion is of great importance in the history of modern thought, and it was proclaimed with much rejoicing and vigour as a great achievement of science, whilst some of its chief advocates seemed at times to forget the extreme awkwardness of the inferences which had to be made from it. The doctrine may be stated in Latin in the form of the familiar dogma, “Omne vivum ex vivo,” every living thing from a living thing. Just as the existence of a man is quite sufficient to prove to us the prior existence of living human parents, just as we feel sure that every beast of the field has had living parents and that every oak has sprung from an acorn developed in a previous oak, so, according to the doctrine of “Omne vivum ex vivo,” we must believe that every living creature, whether human, animal, or vegetable, whether as big as the mammoth or as small as the smallest microbe not one-twenty-thousandth part of an inch in diameter, has sprung from living parents. Nature, according to this doctrine, was divided--as Nature, being a mighty whole, can never be divided--into two absolute categories, the living and the lifeless, or living matter and dead matter. Dead matter was notoriously dead and impotent, and life could not conceivably arise in it, though it could be used by life for purposes of food. On the other hand, living matter rejoiced in the possession of all those great attributes which lifeless matter lacked, and, in accordance with the contrast between the two kinds of matter, the living could never be produced from the lifeless but only from the living: for every creature, microbe or mammoth or man, we must trace back in imagination a series of living ancestors, differing perhaps in various characters, but always living. This series must be traced back and back and back until----? [Sidenote: Life Evolved from the Lifeless] And there the difficulty arose. For the uninhabitableness of the primitive earth was a fact of which men of science were as certain as if from some habitable planet they had been able to gaze upon it. Notwithstanding the dogma of “Omne vivum ex vivo,” it was impossible to assert that every living creature has an _endless_ series of ancestors. How, then, did life begin? What we may call the doctrine of the older orthodoxy--the doctrine of special creation, of supernatural interposition for the introduction of a new entity into the scheme of things--offered one alternative. To accept it, however, would be to abandon the whole modern conception of natural law and of a universe which was not created once on a day, and has not been tinkered with subsequently, but from everlasting to everlasting is the continuous expression to us of the Infinite and Eternal Power which to some eyes it veils and to others it reveals. Unless we are to abandon our philosophy, this alternative cannot be accepted, and it is now accepted by no philosophic thinker. [Illustration: BUFFON PLATO LAMARCK BERTHELOT HERSCHEL CLERK MAXWELL D^{R.} BASTIAN DARWIN TYNDALL HUXLEY LORD KELVIN SPENCER MASTER THINKERS WHO HAVE CONTRIBUTED TO OUR KNOWLEDGE OF LIFE Photos by Gerschel, Maull & Fox, E. Walker, London Stereoscopic, Barraud, and Mills ] Thus, whether “Omne vivum ex vivo” be true or false to-day, we are compelled to accept the only other alternative, which is that it has not always been true, or, in other words, that life was spontaneously evolved from the lifeless (so-called) at some remote age in the past. Just at the present time philosophic biology is out of fashion. Minds of the great cast which endeavour to see things in their eternal aspect have been lacking to the science of life since the days when Huxley and Spencer were in the plenitude of their powers. Anyone who cares to compare the principal reviews of the last decade with those same reviews from the year of, say, 1875 to 1890, can readily see this fact for himself. In the absence of that deliberate thought and discussion without which clear ideas on any subject are impossible, what may be called the official opinion of biology at the present time is thus most remarkable and contradictory. On the one hand, it is strenuously asserted as a matter of dogma that at the present day no life is produced or producible upon the earth except by the process of reproduction of previously existing life; and on the other hand it is asserted--when the direct question is put, though otherwise the subject is simply ignored--that life must somehow or other have been naturally evolved in the past, presumably once and for all. I have called this opinion contradictory, and it is indeed far more contradictory and unsatisfactory than it may at present appear. The obvious question that the critic asks is, “If then, why not now?” [Sidenote: “If then, why not now?”] [Sidenote: Is Life Now Arising from the Lifeless?] The answer alleged is that, of course, the experiments of Pasteur and Tyndall, to which some reference must afterwards be made here, merely demonstrated the impossibility of the spontaneous generation of life in our own day or under any conditions similar to those of our own day; but doubtless the first few simple forms of living matter arose by natural processes at some distant epoch “when the conditions were very different from those that obtain to-day.” Now it happens to be true that every difference between past and present conditions which physics and geology and chemistry can assert tends to the probability that if spontaneous generation is impossible now, it must have been a hundredfold more impossible a hundred million years ago. Yet for some three decades the great majority of biologists have been content to believe that spontaneous generation is impossible now, even though land and sea and sky are packed with organic matter under the very conditions which obviously favour life--as the all but omnipresence of life abundant to-day demonstrates--but that spontaneous generation was possible in the past when, by the hypothesis, there was no organic matter present at all, and when life had to arise in the union and architecture of such simple substances as inorganic carbonates! Such biologists are like those who know that the human organism can be developed from the microscopic germ in a few years, but find it incredible that man can have been developed from lowly organisms in æons of æons. Nor has any living biologist even attempted to make an adequate answer to the question, why what is impossible now should have been possible a hundred million years ago. On the contrary, so soon as the matter is looked at philosophically, we see that all the probabilities, all the analogies, all the great generalisations of science, are in favour of the belief that life must be arising from the lifeless now, as in the past, whenever certain conditions, such as the assemblage of carbon, oxygen, nitrogen and hydrogen in the presence of liquid water, are satisfied. For the moment, however, I propose to postpone this question of the truth of “Omne vivum ex vivo” at the present day, for I desire to throw into the forefront of my argument two quite recent developments of science, unreckoned with because non-existent in the controversy of the ’seventies, and in my judgment not yet duly appraised to-day. In the present and future discussion of the manner and causation of that supreme event in the earth’s history, the beginning of life upon it, we must reckon with two new orders of inquiry relating to facts unthinkably contrasted in physical magnitude yet equally relevant to our subject. The first series of facts with which I will deal are _astronomic_, and the second _atomic_. [Sidenote: The Evidence from Other Worlds] [Sidenote: Vegetable Life on Mars] In discussing the origin of life upon the earth, we of the twentieth century must recognise such facts as may be obtainable in regard to life upon other orbs than ours. Now, in the first place, there is at least one illustrious contemporary astronomer, Professor Pickering, the chief living student of the moon, in whose opinion there are many evidences upon our satellite of the action of vegetation, either past or present. This, of course, is not the place for a discussion of that evidence; it is, however, the place to record the most highly qualified opinion at present obtainable, and to remind ourselves of the certainty that when the moon was first borne--or born--from the earth, life cannot possibly have been evolved, since the conditions of temperature alone, to name one factor, were such as life could not sustain, no liquid water being extant. There is some reason to suppose, then, that, whatever the present case may be, life was at one time spontaneously evolved upon the moon. The second piece of astronomical evidence relevant to our inquiry is afforded by the planet Mars. This, of course, is a much controverted question, which cannot receive any discussion here. It suffices to note that Professor Lowell, who is admittedly the greatest living authority on Mars, has observed and photographed, not merely to his own satisfaction, but to that of an ever increasing number of astronomers, signs of vegetation upon Mars. I will say nothing here as to the existence of intelligent beings there. That fascinating and momentous question, upon which there will doubtless be difference of opinion for some time to come, does not now concern us. It is of quite sufficient significance for our present purpose if the existence of merely vegetable life, and no more, upon the planet Mars can be demonstrated, and there are now very few astronomers indeed who question this demonstration, however chary they may be of going any further. I submit that the question of the beginning of life upon the earth should not be considered without reference to the evidence which suggests the spontaneous origin of life upon the moon, and to the practically positive demonstration of the present existence, with seasonal alternations, as on our own earth, of vegetable life in the watered areas of Mars. [Sidenote: The Earth’s Crumbling “Foundations”] These considerations were entirely unknown to the great controversialists of a generation ago; but there is another order of facts, entirely unimagined by them, which are now demonstrable and admitted. For them, or for most of them, the ancient conception of matter which we trace to Plato was substantially true; nay, more. The recent work of the physicists and chemists had endowed that ancient conception of matter as gross and inert and dead with a new concreteness and vividness. One of the greatest physicists of the age, James Clerk-Maxwell, in his famous address to the British Association, spoke of atoms as the “foundation stones of the visible universe, which have existed since the creation unbroken and unworn.” The accepted conception of an atom was that of a passive thing; it had its own inherent shape and properties, which were impressed upon it at its creation. It had “the stamp of the manufactured article,” as Sir John Herschell said, and throughout its endless history it responded to and behaved under the influence of external forces in due accordance with its shape and size. But it was unchangeable, inert and brute, the sport of its surroundings, like the mote in the sun-beam. [Sidenote: Immeasurable Ocean of Energy] But to-day we stand amazed at such conceptions. We have learnt that within the atoms of matter there is a fund of energy so incalculably vast that the sum total of all the energies previously recognised, and now to be styled extra-atomic, is as nothing compared with it. This is a change indeed, that all the energies hitherto known to us should be merely the overflow trickling from the immeasurable ocean of the intra-atomic energy, the very existence of which has been formally and repeatedly denied by practically all thinkers from Plato down to our own time. Matter is not gross and inert, brute and dead. The atom, the so-called unchangeable foundation stone, is, on the contrary, itself an organism, the theatre of Titanic forces about which we at present know practically nothing except that they certainly exist, and are powerful beyond all our previous conceptions. The atom is no atom, but a microcosm; it is no more the unit of inorganic matter than the cell is really the unit of living matter. Now it is surely evident on consideration, though the significance of the change has been ignored, that the whole discussion of the spontaneous origin or evolution of life in matter takes an entirely new shape when our old and widely erroneous conception of matter is abandoned, and a true one is substituted. Life is a marvellous and characteristic demonstration of energy. When the origin of this energy in matter was formerly discussed, we were told that the constituent parts of matter contain no energy at all, but now we know that a quite overwhelming proportion of the sum total of universal energy is to be found there, and nowhere else. This is one of the most revolutionary advances in the whole history of thought, and its full significance has yet to be recognised. There must also be added an essential to any future discussion of this question, the extraordinary achievement of synthetic chemistry, of which Professor Berthelot was the grand master. As long ago as 1828 it was shown that there was at least one exception to the doctrine of the vitalists, that chemical compounds characteristic of living matter cannot be built up except by the living organism. To-day chemistry has succeeded in building up alcohols, starches, sugars, and even the forerunners of the proteids themselves, from the inorganic elements in the laboratory, under the action of non-vital forces. This fact could not be reckoned with a generation ago. [Sidenote: Can Chemistry Build Up Life?] We are now entitled to state very briefly the sequence of events which may reasonably be imagined as culminating in the origin of life upon the earth _for the first time_. Whatever we may hold as to the present, we have to recognise that the origin of life for the first time constituted a fact utterly different in certain essentials from any origin of life that may be expected to be occurring to-day. The capital fact is that in the beginning there was no organic matter to serve as food material. If ever there was a case in which it is the first step that costs, it is here. Nothing can be easier than to imagine the spontaneous origin of life in organic matter to-day, favoured with sun and water and air. The case is far different when a primary origin in inorganic matter has to be conceived. But of some things we are certain. We are certain, for instance, that so long as the earth’s surface temperature was above that of boiling water, no life was possible. It was not until the gaseous water in the atmosphere became liquefied by the lowering of the earth’s temperature that the production of life became possible. The first seas were seas of boiling water, or rather water infinitesimally below the boiling point, and we may reasonably suppose, with Buffon, that the Polar seas, being the first to cool, must have provided the first “nest” for life upon the earth. I assume, of course, that this essay will be read in conjunction with that of Professor Sollas upon the formation of the earth [page 79], and that of Dr. Wallace upon the exquisite adaptation between life and the earth to-day [page 91]. [Sidenote: The Study of Ferments] But how were those complex organic bodies formed, especially those vastly complex proteids with which all life whatsoever, as we know it, is invariably associated? Apart from the laboratories of the synthetic chemists of to-day, these compounds are always the products of pre-existing life, and yet without them there could be no pre-existing life. [Sidenote: Mystery of the Cell] [Sidenote: Is the Cell a Product of Evolution?] It is my belief that this most difficult question, which quite baffles us, will seem simple and straightforward in another generation, when science has devoted itself on a large scale to a study now in its very infancy--I mean the study of those curious bodies which chemists call ferments. The properties of ferments are shared both by the familiar ferments, such as trypsin and pepsin, and also by certain inorganic substances, such as the metal platinum. Now, though pepsin is a product of living cells, platinum is certainly not. Altogether apart from the living world there are substances which have powers of fermentation; and ferments do not act exclusively, as is erroneously supposed, in breaking down complex compounds, but also build them up from their constituents. The powers of a ferment, moreover, are, so far as we know, inexhaustible. All life whatever is exercised by ferments, and it is true that life, chemically considered, is “a series of fermentations.” Now, there is quite recent evidence already which seems to show that certain ferments, acting in suitable material, have the power of reproducing themselves--that is to say, of converting that material into their like. These facts are highly suggestive, and it is difficult to refrain from suggesting that the gap between living and lifeless matter, which seemed so absolute to our ancestors, and which even to us, who have a new conception of matter, seems wide enough, may yet be bridged by the ferments. We are far too apt, I think, to assume that when we can see no intermediate stage there were no intermediate stages, and thus to make difficulties for ourselves. We declare that life began as a single cell, which was the starting-point of organic evolution. I myself believe rather that the cell constitutes the acme of a vast epoch of evolution, which may yet be reproduced in brief in the laboratory. Denying or declining to think of this, the biologist who knows the amazing complexity and intricacy of the architecture of the cell may well decline to believe that such a thing could spring with a single jump from inorganic matter. We preach and go on preaching that Nature does nothing by jumps, and in the same breath we declare that life began as a simple cell. In another hundred years we may begin to realise that a cell in its own measure and on its own scale is an organism, as complex and mature a product of evolution as a society, or, for the matter of that, as the atom of modern chemistry! But the reader will legitimately declare that so long as the spontaneous generation of life to-day in the most favourable circumstances is a proved impossibility, he cannot be expected to accept the doctrine of its spontaneous origin in the past. There are signs, however, that the biologists are now beginning to listen to Dr. Charlton Bastian, the sole survivor from the great controversy of the ’seventies, whose book, “The Evolution of Life,” was published only a few months ago. Against Pasteur and Tyndall and Huxley, Dr. Bastian maintained that their experiments, asserted to be conclusive, were not conclusive--the facts observed were certainly facts, but the deductions were unwarrantable. The experiments only proved the impossibility under the experimental conditions. The difference is the difference between proving what you set out to prove, and begging the whole question. First establish conditions under which spontaneous generation is impossible, then demonstrate its non-occurrence under those conditions, and thence infer that it is impossible under any conditions. [Sidenote: The Creed of the Future] The student is right in declining to believe in the spontaneous beginning of life upon the earth so long as the possibility of spontaneous generation to-day is denied, but there are not a few who think that the most conservative attitude that can be adopted is one of suspended judgment. The present philosophic tendency is undoubtedly in the direction of a return to the ancient conception that matter is not without its own degree of life, and that the distinction between the organic and the inorganic is a distinction of degree and not radical. Nature does not admit of being sorted into any of our puny categories. As the facts accumulate they point more and more definitely towards the opinion that hylozoism, or the doctrine of potential life in all matter, will be part of the scientific creed of the future. Controversies as to the origin of life, judged in the light of this great conception, seem to become trivial if not puerile. Knowing, as we now do, that Plato’s conception of matter was as false as it possibly could be, and having had revealed to us by radio-activity the omnipresence within the very atoms of matter, of forces incessant and stupendous, we find the doctrine of vitalism, however stated, to be wholly meaningless; we find that the gap between the living and the lifeless is by no means abysmal or impassable. [Sidenote: How Long Has Life Existed?] And the definition of life as self-movement seems to become almost comical, for on that definition surely the whole physical universe, the only perpetual motion machine we know of, is itself alive. A discussion of this question can at the utmost only be suggestive. Very few positive assertions have been made, nor can their number be added to, in reference to a question which is bound to be asked: How long has life existed on the earth? The study of radium and its presence in the earth’s crust alone suffices to abolish altogether the old estimates, and new ones cannot yet be substituted. Only it is certain that the past history of planetary life may be far longer than any previous estimate has indicated. It now seems that the earth is not only not self-cooling, but actually self-heating, and if on the older assumption Lord Kelvin could talk of a hundred million years since, so to speak, water first became wet, and life, as we know it, possible, who shall say of how long periods we may speculate now? Meanwhile, the glass-eyed stare vacantly around them and declare that the progress of science means the destruction of the spirit of wonder and reverence. To them we reply in the words of the Earth Spirit in Goethe’s “Faust”: “At the whirring loom of Time unawed, I weave the living garment of God.” C. W. SALEEBY THE MASTERY OF THE EARTH AND HOW MAN OBTAINED IT BY DR. ARCHDALL REID] All the world--at any rate, all that part of the world which is acquainted with the facts--is now agreed that man is a product of evolution, and that his remote ancestors were of different bodily make and shape, and of different mental type and calibre, from their late descendants. No study of human kind can be comprehensive that does not include a survey of the mode by which the faculties that have given man the mastery of the earth were evolved. [Sidenote: We Know the Present by the Past] A history of his evolution, based, like a political history, on episodes, cannot, of course, be written. But man is a bundle of parts and capabilities. By comparing the civilised being with the savage and the savage with lower animals, we are able to trace, in many important particulars at least, his natural history with a degree of certainty to which, I think, no political history can aspire. As our comprehension of adult man is helped by a knowledge of the development of the child, so our understanding of our species is aided by a study of its past. Armed with some clear conceptions of what man was, and is, we shall be the better fitted to investigate social and political change, and to perceive how it happens that while some nations have inherited the earth and the fruits thereof, others have stagnated or fallen into decay. [Sidenote: How Man Learns by Experience] At a certain stage in his development the caterpillar builds himself a cocoon. His dwelling is a wonderful structure, but from our human point of view the remarkable thing is that he does not learn to build it. He may never have seen a cocoon before, and he constructs only one in his life. Yet his work is perfect, or at least very excellent, and it is as good in its beginnings as in its endings. Evidently he owes nothing to experience, but is impelled and guided throughout by a faculty which we term _instinct_. An instinct may be defined as an innate, inherited impulse, an inclination to do a certain definite act, the instinctive act, on receipt of a certain definite stimulus or incitement to action. In the case of the caterpillar the stimulus appears to be the sight at the proper time of a suitable spot in which to build a cocoon. Since this particular impulse does not appear at the beginning of conscious life, it is termed a deferred instinct. Man, on the other hand, cannot build his house unless he first learns how to build. He depends, not on instinct, but on experience. The faculty by means of which experience is stored in the mind is _memory_. The faculty by means of which we use stored experience to guide present or future conduct is _intelligence_. When the contents of memory are very vast, and the processes of thought by which they are utilised comparatively difficult and complex, intelligence is termed _reason_. Intelligence and reason depend, therefore, on memory, on ability to learn, on capacity to profit by experience. Memory is not the whole of intelligence, but it is the basis of it. Without memory there could be feeling and emotion, but no thought, for the materials of thought would be lacking. [Sidenote: Instinct in Place of Memory] [Sidenote: The Basis of Rational Action] We always measure the intelligence of an animal by its power of profiting by experience. Thus, a cat is more intelligent than a rabbit because it can learn more; a dog, for the same reason, is still more intelligent. A purely instinctive animal, one that has no memory, can have no conception of its past, and therefore no idea of its future. It lives wholly in the immediate present; feeling, but not thinking. It acts entirely on inclination, not on reflection. It makes provision for the future, not with any notion of providing, but simply because it has an impulse to a certain course of action, the performance of which gives it pleasure of the kind a child derives from playing or eating, and with the ultimate result of which it is no more consciously concerned than a child. If a caterpillar sheltered in a hole with the idea, founded on past experience, of avoiding danger, his action would be intelligent. If, appealing to a memory in which a great number of complex experiences were stored, he took thought and designed himself a shelter in which provision was made for all sorts of _remembered_ dangers, his action would be rational. But if, making no appeal to the past nor taking thought for the future, he builds only because impelled by an innate impulse, then, no matter how elaborate the edifice he rears, his action is instinctive. Animals low in the scale of life--for example, most insects--appear incapable of learning. But often they are wonderfully equipped by instinct. The details of the behaviour of a small beetle, as quoted from Professor Lloyd Morgan, may not have been quite correctly ascertained, but they are sufficiently accurate for our purpose. A certain beetle (Sitaris) lays its eggs at the entrance of the galleries excavated by a kind of bee (Anthophora), each gallery leading to a cell. The young larvæ are hatched as active little insects, with six legs, two long antennæ, and four eyes, very different from the larvæ of other beetles. They emerge from the egg in the autumn, and remain in a sluggish condition till the spring. At that time (in April) the drones of the bee emerge from the pupæ, and as they pass out through the gallery the Sitaris larvæ fasten upon them. There they remain till the nuptial flight of the Anthophora, when the larva passes from the male to the female bee. Then again they wait their chance. The moment the bee lays an egg, the Sitaris larva springs upon it. Even while the poor mother is carefully fastening up her cell, her mortal enemy is beginning to devour her offspring, for the egg of the Anthophora serves not only as a raft, but as a repast. The honey, which is enough for either, would be too little for both, and the Sitaris, therefore, at its first meal, relieves itself from its only rival. After eight days the egg is consumed, and on the empty shell the Sitaris undergoes its first transformation, and makes its appearance in a very different form.... It changes into a white, fleshy grub, so organised as to float on the surface of the honey, with the mouth beneath and the spiracles above the surface.... In this state it remains until the honey is consumed, and, after some further metamorphoses, develops into a perfect beetle in August. [Sidenote: Wonderful Instinct of the Beetle] The beetle has sense organs; therefore she feels. But we have no reason to suppose that she remembers or thinks. Memory would be of little use to her; therefore parsimonious Nature bestows little or none. Cast adrift in a hostile world, she must come into existence ready armed by instinct for the battle of life. She has no time to learn, and during the rapid and strange changes in her career has little opportunity of acquiring knowledge that could beneficially guide her future conduct. Since memory and its corollary reflection are most developed in the highest animals, and are imperceptible in the lower, they are clearly later and higher products of evolution than instinct. [Sidenote: Man’s Helplessness at Birth] Family life is a product of memory, for the mate and offspring are _re_-cognised; therefore it always implies some degree of intelligence. The young are watched and protected, and taught by the higher animals. Opportunities are thus afforded of learning about the world, and more particularly of acquiring the traditions, the stored experiences, of the race. With the opportunity to profit by experience comes the ability to profit by it, and with the latter a gradual decay of instinct. Intelligence is substituted, more or less, for unthinking impulse. All the instincts are not lost, but in the higher animals we find no such elaborate innate impulses as in the lower. “Sitaris” is able to fend for herself from the first; but just in proportion as animals are highly placed in the scale of life, so they are helpless at the beginnings of consciousness, but correspondingly capable later. A young pig can run as soon as it is born, but the acquirements of the most learned pig are small compared to that of a dog, which, though more helpless than the pig at birth, is so teachable that he becomes the companion of man. Our domestic animals are all teachable, otherwise we could not tame them. Of living beings man is by far the most helpless at birth. He cannot even seek the breast. In him instinct is at its minimum. For him more than any other animal prolonged and elaborate tuition is necessary; but so vast is his memory, and so great his power of utilising its stored experience, that in later life he is beyond comparison the most capable of the inhabitants of the earth. Compare what even a dull man knows, including the words of a language and its inflections and articulations, with what is acquired by the cleverest dog, and the immensity of the difference is at once apparent. We may take a solitary frog and rear him from the egg in an aquarium. If, subsequently, we remove him to a pond, he will take his place with his fellows at once. He has little, if anything, to learn. Instinctively he knows his food, and how to seek it; his enemies and rivals, and how to escape or fight them; his mate, and how to deal with her; and she knows how to dispose of her eggs. But how forlorn and helpless would be a man reared from infancy in a dark cell out of sight and sound of his kind, and then turned into a world where his _experienced_ fellows struggle for existence! [Sidenote: Fear is the Result of Experience] Traditional knowledge--knowledge, that is, imparted by one generation to the next--is common enough amongst the higher of the lower animals, and forms no inconsiderable part of their mental equipment. Thus we may see the hen teaching her chickens how to seek food, and the cat instructing her kitten how to ambush mice. Birds and mammals inhabiting desert islands have none of that fear of man which in our country they acquire from dire experience. We have a saying, “as wild as a hawk”; but Darwin relates how he almost pushed a hawk from its perch with his gun in the Galapagos Islands. Round our coasts the sea-birds are exceedingly shy; in a harbor they feed from the hand. Formerly the Arctic seals, impelled by fear of bears, inhabited the outer margin of the floes; at the present day they have retreated from the more dangerous neighbourhood of man to the landward edge. Antarctic seals, harried by the great carnivora of the ocean, are watchful in the water; on land or on the surface of the ice, where till lately they met no danger, they may be slaughtered like sheep in a shambles. They are capable of profiting by experience; but they are slow to learn, and can acquire but little. Judged by our human standard, they are very stupid. The means of escape adopted by Arctic seals, and the means of capturing them, the ships and guns adopted by man, furnish a measure of the intellectual difference. [Sidenote: Slavery in the World of Insects] When animals are social, and so have the opportunity of learning, not only from their parents, but from other members of the species, the power of making useful mental acquirements is correspondingly great. It reaches a remarkable degree of development even amongst insects, some species of which live together in great communities. Young ants, for example, are tended with anxious care. It is said that they are led about the nest and instructed by older individuals. They are reported to be playful. Most significant of all is the fact that some species have the habit of capturing slaves belonging to other species, which they take as pupæ, never as adult ants, and to whom, as they develop, they teach their duties. The slaves are neuter individuals, and have no offspring, the supply being maintained by fresh captures. It follows that the slaves must _learn_ their work, and therefore that their performance of it is not instinctive, but intelligent. It is a fair inference that many of the so-called instincts of ants are really acquired habits, bits of knowledge and ways of thinking and acting which are handed down from one generation to the next, not by actual inheritance, but traditionally and educationally, just as children receive from us language, or religion, or a trade. Indeed, there is reason to believe that the power of making mental acquirements has evolved to a greater degree in the favourable environment of the ant-nest than among any other species except man. [Sidenote: Man’s Essential Instincts] The instincts of man, though comparatively few and simple, are yet essential to his existence. He has the instinct of hunger and the instinctive recognition of food as food, the instincts to sleep periodically, to rest when tired, and to sport when rested, the instincts of curiosity and imitativeness, and the deferred instincts of sexual and parental love, and perhaps one or two others. All these innate impulses he shares with the lower animals, but those which impel him to store and use his vaster memory are more developed in him than in any other type. Thus the instinct of sport urges him, not only to develop his limbs, but, through experience, to acquire dexterity and much besides. The little girl turns naturally to her doll, which she handles as she will her baby. The play of a boy as naturally involves contests, which foreshadow the grimmer battles of adult life. As he grows older the character of his sport changes. More and more it becomes an appeal to the wits, an appeal to wider experience and a means of adding to it. [Sidenote: A Child’s Play Fits it for the Future] The higher amongst the lower animals also have their sports, which, in every instance, are adapted to fit the members of the species for the future business of life. Compare, for example, the ambush and pounce of the kitten, the ardent chase and overthrow of the puppy, and the climbing proclivities of the kid. As a general rule, in proportion as an animal is capable of becoming intelligent, and as long as it is so capable, it is inclined to sport. A cat loses the desire early in life, a man retains it to the end. A child’s play, therefore, is no indication of mere frivolity. It is the outward and visible sign of an eager and splendidly directed mental activity. Curiosity also prompts the child to store its memory. Imitativeness impels him to acquire those mental traits which enabled his progenitors to survive in their world. Parental love prompts to the care and instruction of offspring. Very illuminating and beautiful is the instinctive delight of some dull and careworn mother in babyish play with her infant, and her joy when it first “takes notice,” and in its earliest beginnings of speech and locomotion. Every animal species is fitted by its structures and their associated faculties to its particular place in Nature. In some cases it holds its own largely through the evolution of some one structure or group of structures. Thus, the bat is especially distinguished by the great development of its fingers and of the web between them, and the elephant by its trunk. The principal distinguishing physical peculiarity of man is the enormous relative size in him of that upper part of the vertebrate brain which is termed the cerebrum, and, we have every reason to believe, constitutes the organ of memory and thought. [Sidenote: Evolution of Man’s Powers] Associated in a special way with his great brain are his organs of speech and manipulation. These three structures, the brain, the vocal apparatus, and the hand, undoubtedly underwent concurrent evolution by the constant survival, during a period of intense competition, of those individuals who were naturally the best capable of receiving and storing experience, of using it for the intelligent manipulation of objects, and of communicating it to their fellows and descendants through the medium of speech. Even the highest of the lower animals are able to learn from one another only by example or through such very elementary verbal signs as calls, growls, or cries of alarm, which express no more than simple emotions. Their traditional knowledge, therefore, is as nothing compared with that of man, who by means of articulated speech communicates not only information concerning sense impressions and emotions, but complex items of knowledge and processes of thought which have been garnered, elaborated, and systematised during tens of thousands of years by millions of predecessors. Without speech, or some such method of communicating abstruse information, his great brain would be useless. But knowledge and powers of thought are of no avail unless they can be translated into action; and for this the hands are necessary. To set free the fore limbs, which had hitherto been organs of locomotion, for their new function of manipulation, man became a biped, and assumed the erect posture--by no conscious effort, however, but solely by the survival of the fittest in each generation. [Sidenote: Man Paves His Way to Greatness] Savage man, then, differs from the lower animals in that he has a larger brain, a more capacious memory, and greater powers of utilising and communicating its contents. Modern man differs from ancient man because he is the heir of longer experience. Civilised man differs from the savage chiefly in that he has invented and more or less perfected certain artificial aids to speech, written symbols by means of which he is able to store in an available form knowledge immensely more abstruse and voluminous than would otherwise be possible. His books are artificial memories and vehicles of communication of unlimited capacity and unerring accuracy. Moreover, by means of these symbols he is able, as in the mathematics, to perform feats of thinking quite beyond the powers of his unaided mind; just as by means of machinery and other mechanical contrivances he is able to perform physical feats beyond the unaided powers of his body. To memory, then, is due the advance of the savage beyond the lower animal; to tradition, the child of memory, the advance of modern man beyond ancient man; to tradition stored in books the advance of civilised men beyond the savage. To written symbols are due also man’s vast powers for future advance. The brute, the mammoth, the mastodon, the whale, the elephant, and the tiger, became ever more and more helpless in the presence of a knowledge and an ingenuity that gathered with the rolling years, and, though accumulated for ages, were yet relatively new things in this enormously old world. Low animals, in proportion as they lack memory, move in a narrow, instinctive groove. Their mental traits are all inherited, and therefore each individual follows exactly in the footsteps of its predecessor. Since they cannot learn, they cannot adapt themselves to circumstances. Removed from the ancestral environment they perish. Cast in a rigid, inexpansive mould, every individual resembles every other of the same species, as much mentally as physically. [Sidenote: Man can Revert to Savagery] It is different with man. He is preeminently the educable, the reflective, the adaptive animal. Since the experiences of no two men are quite similar, they differ in knowledge, ideas, and aspirations, and, therefore, none are very closely alike mentally. The child does not follow exactly in the footsteps of the parent. So great is human adaptability that, though the mind of the savage differs immensely in all except instinct and power of learning from that of the civilised man, yet, were the child of the latter trained from birth by the former, he could not be other than a savage. On the other hand, utter savages--for example, the Maories of New Zealand--have passed in a single generation from barbarism to civilisation. The average individual amongst us may be trained to fill the rôle of a beggar or a king, a scientist or a monk, a thief or a legislator. He is able to dwell in the Tropics or in the Arctic, in the town or in the wild. Memory, knowledge, intelligence, adaptability, are all links in a single chain of efficiency. [Sidenote: Dawn of Human Life] Memory is of two sorts, conscious and unconscious. The conscious memory contains experiences which can be recollected, such as the words of a language or the sights we have seen. The unconscious memory contains impressions which cannot be recalled to mind, but which are none the less important. Thus, we learn to use our limbs, a process which involves a precise but quite unconscious adjustment of the actions of numerous nerves and muscles, the very names and existences of which are known only to the anatomist. So, also, in youth we unconsciously imitate our fellows, adopting in great measure their mental tones and attitudes without knowing how or when we were influenced. Much, too, that was once capable of being recalled is added to that hidden store, and, though apparently lost, remains potent for good or evil. Our minds are like floating icebergs, of which the visible part is but a fraction of the whole, and are moved by deep currents in a seemingly unaccountable way. At birth the mind of a child, unlike that of a beetle, is practically blank. Sights and sounds and the other feelings convey no meanings to it. But soon the messages sent by the sensation are understood. In a few weeks the child evolves order out of chaos, and comprehends to a wonderful degree the world around it. It learns to move its muscles in a purposeful way, and in a year or two is able to walk and speak a language, and do a vast deal more besides. In these early years, the period of man’s greatest mental activity, are made his most valuable and indispensable acquirements. But as he becomes more and more completely equipped for the battle of life, his powers of adding to the store slowly decline. In adult life the gains are balanced by the losses. In old age the losses exceed the gains. Compare the perfection with which the young acquire the manners of society, and every accent, inflection, and intonation of a language, with the imperfections displayed when learning is undertaken later. [Sidenote: Habits are Imitation Instincts] We learn to do new things, acquire new knowledge, and think new thoughts with toil. But practice brings facility. In the end we perform with ease that which was acquired with difficulty. We cannot, however, unlearn as we learnt, by an act of will. The facility lingers, and, as a consequence, our actions and thoughts, our mental attitudes, our whole outlook on life becomes more or less automatic and stereotyped. In other words, our acquirements come at last to resemble instincts, and are often so misnamed, as when a boy who has learned to dodge is said to avoid a blow instinctively. A being from another planet who for the first time saw a man walking or cycling could not distinguish the nature of these acquirements from such instinctive movements as the running or flying of an insect. The patriotism of a Spartan or a Japanese differs from that of a bee only in its mode of origin. In brief, the low animal is a creature of instincts, the man is a creature of habits, which are nothing other than imitation instincts. [Sidenote: Mankind’s Substitutes for Instinct] A principal function, then, of our faculty of making mental acquirements, of our conscious and unconscious memories, is to supply us with those automatic ways of thinking and acting which are our substitutes for instincts. Our conscious memories supply us with our stereotyped mental attitudes--desires, beliefs, aspirations, habitual way of thinking, and so forth. Our unconscious memories supply our stereotyped ways of acting--the automatic ways of acting we have just considered. It is a principal business of our lives to acquire them; but, though a great advantage is thus gained, one almost as great is lost. We act and think more quickly in familiar situations, but in proportion as we grow older we lose our splendid human capacity for learning. Beyond the verge of our imitation instincts spreads a domain, very wide in the infant, but narrowing as we pass towards old age, which is the real realm of the active intellect. Here, where thoughts and actions are not yet stereotyped, memory gathers fresh harvests, imagination plays, and reason ponders. Here man is a rational being in the strict sense of the word. [Sidenote: Mind and Memory] A little thought renders it evident that a feeble-minded person, an idiot, or an imbecile, is always one with a defective memory. He is unable to profit like the normal individual from experience. The truth that the higher faculties are more often absent in the feeble-minded than the lower is due entirely to the fact that they can be acquired only by people whose receptive powers are well developed. In effect and in fact the feeble-minded person is an instance of reversion to a prehuman mental state. Judged by the human standard, every monkey is an idiot. But the reversion is not complete, for, though the imbecile loses some part of his power of profiting by experience, he regains no part of the lost power of being guided by instinct. Therefore he is correspondingly helpless as compared with a lower animal. Owing to the constitution of the human mind, some decay of the faculty of profiting by experience accompanies advancing age. But it need seldom be so great as it usually is, and never so great as it often is. Certain mental attitudes, certain systems of education, certain environments, leave the mind of the man almost as open as that of a little child; others inflict on it premature senility. An Aristotle or a Darwin learns to the last year of his long life; a Mohammedan or a Tibetan ecclesiastic is old before he has ceased to be young. Convinced that pestilence is due directly to the wrath of God, he scorns the notion that sanitation can be right or useful; believing that the earth is flat, no evidence will convince him that it is round; holding his sacred religion with a steadfast faith, he will murder the heretic rather than think out his propositions. [Sidenote: How the Minds of Men Differ] But habits of stupidity are not confined to particular regions of thought. Becoming almost as incapable of mental change as a beetle, a man may undergo an arrest of mental development which differs from that of the idiot only because it occurs later in life, is less complete, and is acquired, not innate. In his ordinary surroundings he appears a normal person; but placed among people of more open mind, his brute-like inability to learn suggests sharply the resemblance to the feeble-minded child. Let us sum up. Man has conquered the earth because he is pre-eminently the educable, the adaptive animal. His educability--indeed, his whole thinking capacity--depends on his memory. He has few instincts, a fact which increases his mental ductility; but one of the most important of his instincts is imitativeness, which impels him to copy not only such obvious things as the speech of his predecessors, but their mental attitudes as well. In this way not only the actual knowledge and beliefs but also the habits of thought of one generation are handed on to the next. Apart from a few instincts which are more active in the child than in the adult, and two or three others whose appearance is deferred till later life, the whole mental difference between the child and the adult lies in the fact that the former has a great memory in the sense that it is very capable of storing experience, whereas the latter has a great memory in the sense that it has already stored much experience. As parent to child, so one racial generation hands on its acquirements to the next, but with greater certainty; for the parent is not the only influence in the life of the child, who imitates many other people, sometimes more closely than the parent; whereas, since few individuals travel during youth, the young are seldom influenced by others than by members of their own race. Except in times of great change, therefore, racial generations resemble one another even more closely than parents and children. Like individuals, races differ in their mental characteristics. The English have one set of characters, the Japanese another, and the Russians a third. The problem of the extent to which these characters are inborn or acquired is very important to the student of history. Accordingly as we believe they are the one or the other we are driven to accept one or other of two very different readings of the past. [Sidenote: Influences in a Child’s Life] Are races, then, brave or cowardly, energetic or slothful, enlightened or savage, and so forth, by nature or by training? Are the qualities that have enabled some races to flourish, while others are decadent, transmitted as instincts or handed on, as knowledge is? The reader has now materials of a kind not usually found in historical works on which to found a judgment. He must bear in mind that, while an American infant reared by cannibals would retain the bodily characteristics of his race mentally, he could not be other than a savage. He must remember also that some races have altered their mental characteristics very rapidly. Thus, in the fifteenth and sixteenth centuries, immediately after the long Dark Ages, the British and several other European races suddenly became intellectually active and socially progressive. The Japanese supply a more modern, the Greeks and Romans more ancient, instances. The latter quite as suddenly sank into abysmal degradation. Innate mental characters, such as the instincts, usually change so slowly that not merely historical but geological time elapses before the alteration is perceptible. Again, the reader must note that, while the _opinion_ that racial traits are inborn is nearly universal, most men _act_ as if they knew them to be acquired; for nearly all men are careful in training their children, especially with respect to those traits that contribute to the formation of character. [Sidenote: Great Facts to Remember] Doubtless, races of men differ innately in mind as they do in body, but these differences can occur only within narrow limits. The instincts of all races are, of course, very similar, for all the instincts are essential to the preservation of life. But races may differ in strength of instinct, and more especially in powers of memory. Thus it is possible, or probable, that the English, for example, are more capable of profiting by experience than Australian blacks. Certainly, their brains are larger. On the other hand, the brain grows under the stimulus of use, and therefore the larger size of the English brain may be due to more arduous labour. [Sidenote: The Real Value of History] Lastly, the reader must ask himself the question: What mental effects have centuries of freedom or slavery, or of civilisation, or of barbarism, on races? Do they produce innate changes, or do they merely render certain acquirements so nearly universal that their perpetuation by imitation is insured? If he supposes that the changes are innate, he must ask himself the additional question whether they arose through the transmission of parental acquirements to offspring, or through the actual and constant destruction in certain environments of certain definite types of individuals who were thus prevented from leaving offspring and so perpetuating their like. The former hypothesis is now generally repudiated by science. The latter may be true, but as yet has not been supported by evidence; or at any rate is supported only by such evidence as that which Mill and Buckle denounced. In either case, though history may furnish him with intellectual occupation, it will supply few lessons of practical value. If, on the other hand, he has perceived the greatness of the part played in the human mind by acquirement, if he has noted that man is man, a thinking and rational being, the conqueror of the earth, only because he is the most impressionable and therefore the most adaptable of living types, the reader will learn from the racial see-saw of the past what kinds of mental training have conduced to success and happiness and what to ruin, and so perhaps he may find himself in a position to help the fortunes of his people and his children. The real value of history, as in the last analysis of all experience, lies in its educational applications. G. ARCHDALL REID [Illustration: PREHISTORIC MEN ATTACKING THE GREAT CAVE BEARS] [Illustration: THE RISE OF MAN AND THE EVE OF HISTORY] THE WORLD BEFORE HISTORY By Professor Johannes Ranke THE WONDERFUL STORY OF DRIFT MAN [Sidenote: Nature’s Great Book of History] The history of the world is the history of the human mind. The oldest documents affording us knowledge of it lie buried in those most mighty and comprehensive historical archives, the geological strata of our planet. Natural philosophy has learned to read these stained, crumpled, and much-torn pages that record the habitation of the earth by living beings; but only a few sections of this book of the universe have yet been perused, and these appear but fragmentary in comparison with the whole task. The passages that relate to the human race are small in number and often even ambiguous, and it is only the last pages that can give an account of it. The oldest undisputed traces of the presence of man on the earth that have hitherto been discovered are met with in the strata of the Drift Epoch, and it is only during the last generation that the existence of “Drift Man” has been palæontologically proved beyond dispute. The late Sir J. Prestwick believed, however--and his results have been confirmed by later discoveries--in the existence of evidence of the presence of man in Western Europe before the present river system of our land was established, long before the age of the “Drift” relics. The evidence consists of rudely shaped pieces of flint, apparently artificially chipped along one or more edges. These supposed implements are termed “Eoliths.” They were first discovered by Mr. Benjamin Harrison in the high-level plateau, probably of the Upper Pliocene Age, in Kent, and their significance is now widely accepted. Up to the middle of last century research appeared to have established as a positive fact that man could not be traced back to the older geological strata; remains of man were said to be found only in the newest stratum of the earth’s formation--in the alluvial, or “recent” stratum. The bones of man were accordingly claimed to be sure guides to the geological formations of the present time, as the bones of the mammoth and cave-bear were to the strata of the Drift. Where traces of man were found it was considered as proved by natural science that the particular stratum in which they occurred was to be allotted to the most recent system, which we see forming and being transformed under our eyes at the present day. [Illustration: A PAGE FROM NATURE’S HISTORY BOOK It is in the successive layers of the earth’s strata with their human and animal remains that we read the story of the past. Embedded in the earth itself we have the existence of “Drift Man” established. Our illustration is that of a section of the famous Kent’s Cavern, near Torquay, which is rich in prehistoric remains. ] [Sidenote: The Theory of Natural Catastrophes] While it was declared that man belonged to the alluvial stratum, it was at the same time stated, according to the doctrine of Cuvier, which had the weight of a dogma, that man could not have belonged to an older geological stratum or era, and therefore not even to the next older one, the Drift. The beginning and the end of geological eras are marked by mighty transformations which have caused a local interruption in the formation of the strata of the earth’s surface. In many cases we can point to volcanic eruptions as the chief causes, but more especially to a change in the distribution of land and water. Cuvier had conceived these changes involving the transformation to have been violent terrestrial revolutions, the collapse of all existing things, in which all living beings belonging to the past epoch must have been annihilated. It appeared impossible that a living thing could have survived this hypothetical battle of the elements, and passed from an older epoch into the next one; and the new epoch was supposed to have received plants and animals by re-creation. All this had to be applied to man also; he was supposed to have come into existence only in the alluvial period. Not without consideration for the Mosaic account of the Creation, which, like the creation legends of numerous peoples scattered far and wide over all the continents of the earth, tells of a great deluge at the beginning of the present age, the Pleistocene Epoch of the earth’s formation preceding the present period had been termed the Flood Epoch, or Diluvium. In its stratifications it was thought that the effects of great deluges could largely be recognised; but the human eye could not have beheld these, for, according to the catastrophe theory, it appeared out of the question that man could have been “witness of the Flood.” [Sidenote: What Actually Happened] Here modern research in the primeval history or palæontology of mankind begins, starting from the complete transformation of the doctrine of the geological epochs brought about by Lyell and his school. Proofs of terrestrial revolutions, as local phenomena and epoch marks, are doubtless to be found, imposing enough to make the views of the older school appear intelligible; but, generally speaking, a complete interruption of the existing conditions did not take place between the periods. Everything tends to prove that even in the earlier eras the transformation of the earth’s surface went on in practically the same way as we see it going on before our eyes to-day in a degree that is slight only to appearance. The effects of volcanic action; the rising and sinking of continents and islands, and the alteration in the distribution of sea and land caused thereby; the inroads of the sea and its work in the destruction of coasts; the formation of deltas and the overflowing of rivers; the action of glaciers and torrents in the mountains, and so forth, are constantly working, more or less, at the transformation of the earth’s surface. [Sidenote: Nature’s Unbroken Chain] As we see these newest alluvial deposits being formed, so in principle have the strata of the earlier eras also been formed, and their miles of thickness prove, not the violence of extreme and sudden catastrophes, but only the length of time that was necessary to remove such mighty masses here and pile them up there. It was not sudden general revolutions of great violence, but the slowly working forces, small only to appearance, well known from our present-day surroundings, which destroy in one place and build up again in another with the material obtained from the destruction--it was these which were the causes of the gradual transformation of the earth in all periods of its history comparable to the present. According to this new conception of geological processes, a general destruction of plants and animals at the end of eras, and a new creation at the beginning of the following ones, was no longer a postulate of science as it had been. The living creatures of the earliest eras could now be claimed as ancestors of those living to-day; the chain seems nowhere completely broken. The ancestors of the human race were also to be sought in the strata of the earlier geological periods. [Illustration: This indicates a vast stretch of the lost land of England, looking towards the Scilly Isles from Land’s End. All between the broken lines was once land as far as Scilly, thirty miles away and fifty miles thence to Lizard Point.] [Illustration: In old maps Bavent was formerly the most easterly point of England; now that is Lowestoft.] [Illustration: The coast of England is being slowly worn away by the sea. In many places houses have been swallowed up. Here we see the disintegrating process going on at Holderness, where the sea front presented this appearance after a gale.] [Illustration: SLOW INFLUENCES THAT DESTROY IN ONE PLACE AND BUILD UP IN ANOTHER The coming of the sea over the land is so slow as to be almost imperceptible, but these pictures illustrate its progress. The pictures in the upper half of the page show how the sea is encroaching on the coast; the opposite result is shown in the bottom view from Reigate Hill, where we see an ancient arm of the sea now a rich and populous valley. ] Among the forces which we find attended by a transformation of the fauna and flora of the earth’s eras, the influences of climatic changes in particular are clearly and surely shown. In that primeval period in which the coal group was formed the climate in widely different parts of the earth was comparatively equable, little divided into zones, and of a moist warmth; this is proved by the really gigantic masses of plant growth implied by the formation of many coal strata, in which the remains of a luxuriant cryptogamic flora are everywhere embedded. In Greenland, in the strata belonging to the chalk period, and even in the deposits of the Tertiary Period, which immediately precedes the Drift Era, the remains of higher dicotyledonous plants of tropical character are found. The occurrence of palæozoic coral reefs in high latitudes also goes to prove that the temperature of the sea water there was higher at that time: in fact, that a tropical climate existed in the farthest north--an extreme contrast to the present ice-sheet on its land and the icebergs of its seas. [Illustration: EUROPE BEFORE THE BRITISH ISLES WERE FORMED This map and section illustrate the coast line of Prehistoric Europe when the British Isles were part of the Continent and the North Sea did not exist. The black parts of the section were all above the level of the Atlantic. ] [Illustration: THE SUBMERGED LANDS OF EUROPE This map and section show how the Continental shelf of Europe runs out to the Atlantic, and how enormous is the area now submerged in the comparatively shallow water of the North Sea, the Irish Sea, and the Channel. ] In Central Europe the climatic conditions can have been only slightly different. During the middle Tertiary Period palms grew in Switzerland; and even at the end of the Tertiary Period, as it was slowly passing into the Drift Era, the climate in Central Europe was still warmer than now, being much like that of Northern Italy, and its protected west coast the Riviera. There was also a rich flora, partly evergreen, and a fauna adapted to such mild surroundings. Even in the oldest (Preglacial) strata, and again in the middle (Interglacial) strata of the Central European drift, there was still an abundant plant-growth requiring a temperate climate, at any rate not more severe than Central Europe possesses at the present day. Our chief forest trees grew even then--the pine, fir, larch, and yew, and also the oak, maple, birch, hazel, etc. On the other hand, Northern and Alpine forms are absent among the plants. The same holds good of the animal world, which was certainly much farther removed than the plant world from the conditions prevailing now. The gigantic forms--the elephant, rhinoceros, and hippopotamus--appear particularly strange to us, as also the large beasts of prey--the hyena, lion, etc. But besides these, and the giant deer with its powerful antlers, and two large bovine species--the bison and the urus--there were also the majority of the present wild animals of Central and Northern Europe that were originally natives--as the horse, stag, roe, wild boar, and beaver, with the smaller rodents and insectivora, and the wolf, fox, lynx, and bears, of which last the cave-bear was far larger than the present brown bear, and even than the Polar and grizzly bears. We have sure proofs that through a decrease in the yearly temperature a glacial period set in over Europe, North Asia, and North America, burying vast areas under a sheet of ice, of the effect and extent of which Northern Greenland, with its ground-relief veiled in inland ice, can give us an idea. The immediate consequence of this total climatic change was an essential change in the fauna. Forms that were not suited to the deteriorated climate, that could neither stand it nor adapt themselves to it, were first compelled to retire, and then were exterminated. This fate befell the hippopotamuses, and also one of the two elephant species, _Elephas antiquus_, with its dwarf breeds in Sicily and Malta, probably thus developed by this retreat; then the rhinoceros-like _Elasmotherium_, a species of beaver; the _Trogontherium_, and the powerful cat _Machairodus_ or _Trucifelis_, which still lived in England, France, and Liguria during the Drift Period. Other animals, like the lion and hyena, withdrew to more southerly regions, not affected by the increasing cold and more remote from its effects. [Sidenote: The Older Drift Animals] On the other hand, according to Von Zittel’s description, an immigration of cold-loving land animals took place, which at the present day live either in the Far North or on the wild Asiatic steppes, or in the high mountain ranges. These new immigrants mixed with the surviving forms of the older drift fauna. The latter lived, as we have seen, by no means in a warm climate, but only in a temperate “northerly” one, even in the warmer periods of the epoch. So we can understand that many of this older animal community were well able to adapt themselves to colder climatic conditions, and among them two of the large Drift pachydermata, the elephant and rhinoceros, whose kin we now find only in the warmest climes. But a thick woolly coat made these two Drift animals well fitted to defy a raw climate--namely, the woolly-haired mammoth, _Elephas primigenius_, one of the two Drift species of elephants of Europe, and the woolly-haired rhinoceros, _Rhinoceros antiquitatis_. A second species of rhinoceros, _Rhinoceros merckii_, was also preserved, and maintained its region of distribution. The horse was now more largely distributed, and inhabited the plains in herds; but, above all, the reindeer immigrated along with other animals that now belong only to Far Northern and Arctic regions, and pastured in large herds at the edges of the glaciers. With the reindeer, although less frequent, was the musk-ox of the Far North, besides many other cold-loving species, such as the lemming, snow-mouse, glutton, ermine, and Arctic fox. Many of the animal forms that were very frequent then, in the Drift Period, appear now in Central Europe only as Alpine dwellers, living on the borders of eternal snow, such as the ibex, chamois, marmot, and Alpine hare. [Sidenote: The Animal Invasion of Europe] [Sidenote: The Change of the Ice Age Climate] Of special importance for our main question is the great invasion of Europe by Central Asiatic animals; immigrants direct from the Asiatic steppes pushed westward “as in a migration of nations,” among them the wild ass, saiga antelope, bobac, Asiatic porcupine, zizel, jumping mouse, whistling hare, and musk shrew-mouse. According as the glaciers and inland ice grew or shrank, the animals of the glacial period advanced more or less far to the North or retired more to the South, extending or reducing their range of distribution. The Glacial Period was no invariable climatic phenomenon. It is perfectly certain that a first Glacial Period with a low yearly temperature, under the influence of which the ice-masses, with their moraines, advanced a long way from the North and from the high mountains, so that in Germany, for instance, only a comparatively narrow strip remained free and habitable for higher forms of life between the two opposing rivers of ice--was succeeded by at least one period of warmer climate, and that certainly not a short one. The mean yearly temperature had increased so much that the ice-masses melted to a considerable extent, and had to retire far to the North and into the high valleys of the Alps. In this warmer Interglacial Period, as it is called, the Drift animals advanced far to the North, especially the mammoth, which, with the exception of the greater part of Scandinavia and Finland (districts which remained covered with ice during the Interglacial Period), is distributed throughout the drift strata of the whole of Europe and North Africa, and as far as Lake Baikal and the Caspian Sea in Northern Asia. Even the older Drift fauna, so far as it had not yet died out or retired, returned to its old habitats, so that the Interglacial fauna of Central Europe appear very similar to the Preglacial fauna. A long-sustained decrease of temperature led once more to the growth of the ice, which in this second Glacial Period almost reconquered the territory it had won at first. In consequence of these oscillations in the climatic conditions of the Drift Era as a whole, we have to distinguish the Preglacial Era and the Interglacial Era, as warmer sub-periods of the Drift, from the real Glacial Periods. The latter appear as a first, or earlier, and a second, or later Glacial Period, as remains of which the zone of the older moraines and the zone of the later ones clearly mark the limits of the former glaciation. [Illustration: Alpine Hares The Chamois The Ibex The Marmot Dando TYPES OF ANIMALS SURVIVING IN CENTRAL EUROPE FROM THE DRIFT PERIOD Many of the animal forms that were very frequent in the Drift Period appear now in Central Europe only as Alpine dwellers, living on the borders of eternal snow. Such are the ibex, chamois, marmot, and Alpine hare. ] [Sidenote: Breaking up of the Earth] It was this second deterioration of the climate, with the fresh advances made by the glaciers and masses of inland ice, which definitely did away with the older Drift fauna that was not equal to the sudden climatic change. Nor did the woolly-haired rhinoceros, the _Rhinoceros merckii_, and the cave-bear survive the climax of the new Glacial Period. Even the woolly-haired mammoth succumbed. It and the woolly-haired rhinoceros, accompanied by the musk-ox and bison, had made their way into the Far North of Asia. But while the two last species bore the inclemencies of the climate, the rhinoceroses and elephants met their end here. And yet they had long preserved their lives on the borders of eternal ice. Whole carcases, both of the woolly-haired and Merckian rhinoceroses, and also of the woolly-haired mammoth, the bison, and the musk-ox, with skin and hair and well-preserved soft parts, have been discovered in the ice and frozen ground between the Yenisei and Lena, and on the New Siberian Islands at the mouth of the Lena. The carcases of the mammoth and rhinoceros found imbedded in the ice were covered with a coat of thick woolly hair and reddish-brown bristles ten inches long; about thirty pounds of hair from such a mammoth were placed in the St. Petersburg Natural History Museum. A mane hung from the animal’s neck almost to its knees, and on its head was soft hair a yard long. The animals were therefore in this respect well equipped for enduring a cold climate. As regards their food they were also adapted to a cold climate, traces of coniferæ and willows--that is, “Northern plants”--having been found in the hollows of the molar teeth of mammoths and rhinoceroses. The mammoth proves to have had greater resisting power, and to have been more fit for further migrations, than the rhinoceros. The latter’s range of distribution extended over the whole of Northern and Temperate Europe, China and Central Asia, and Northern Asia and Siberia. But, as we have seen, the mammoth penetrated not only into North Africa, but, what is of the highest importance for the proper understanding of the settling of the New World, even into North America. [Sidenote: Companions of the Mammoth] [Sidenote: Mammoth’s Arrival in Europe] The connection which in earlier geological periods had united Europe, Asia, Africa, and North America in the greatest homogeneous zoogeographical kingdom, the Arctogæa, was broken during the Tertiary and Drift Periods, so that several zoogeographical provinces were formed. The connection with North America was the first to be broken, so that even in the last two divisions of the Tertiary Period, the Miocene and Pliocene Epochs, the Old and the New Worlds stood in the relation of independent zoogeographical provinces to one another. Now, it is of the greatest importance to note that during the Drift Period North America again received some Northern immigrants from the Old World, according to Von Zittel “probably viâ Eastern Asia.” Consequently, during the Drift Period communication existed, at least temporarily, between Asia and North America in the region of Bering Strait, sufficient to allow the mammoth and some companions to migrate from the one continent to the other. In Kotzebue Sound mammoth remains are found in the “ground-ice formation,” together with those of the horse, elk, reindeer, musk-ox and bison. Mammoth remains are also known to have been found in the Bering Islands, St. George in the Pribylov group, and Unalaska, one of the Aleutian Islands. In that period the mammoth arrived in the New World as a colonist driven from the Old. It spread widely over British North America, Alaska, and Canada; it has also been found in Kentucky. A relatively recent union of the circumpolar regions of the Northern Hemisphere--of Europe, Asia, and North America--is also proved by the occurrence of animals that we recognise as companions of the mammoth, but which, surviving the Glacial Period, are still distributed over the whole region, such as the reindeer, elk, and bison. The absence in Asia of several animals specially characteristic of the European Drift (the hippopotamus, ibex, chamois, fallow-dear, wildcat, and cave-bear) explains also their absence in the North American Drift fauna. It is particularly strange that the cave-bear did not reach Northern Asia. It is otherwise the most frequent beast of prey of the Drift Period, and hundreds of its carcases often lie buried in the caves and clefts it once inhabited. In Southern Russia numerous remains of it are found, whereas in the English caves it is rarer, the cave-hyena predominating here. Apart from the exceptions just mentioned, J. F. Brandt considers North Asia and the high Northern latitudes to be the region in which the European, North Asiatic, and North American land fauna had concentrated during the Tertiary and Drift Periods, and whence their migrations and advances took place according as it grew older. As the northern fauna spread over more southern latitudes during the Drift Period, they took possession of the habitats of the species there belonging to the Tertiary Period, drove them back into tropical and subtropical regions, and formed the real stock of the Drift fauna, as described by Von Zittel in his “Palæozoology.” [Illustration: AN ACTUAL PHOTOGRAPH OF THE PREHISTORIC MAMMOTH This stuffed carcase of a mammoth is the rarest treasure of St. Petersburg Academy. Skeletons of these creatures exist in plenty, but actual carcases are very rare. This was found embedded in the ice on the New Siberian Islands. One carcase so embedded was discovered five years before it could be freed from the ice. ] One thing is certain--namely, that the northern borders of Siberia were not the real home of the mammoth and its companions; the original habitat of these animals points to the far interior of Asia, particularly to the wild table-lands, where they so far steeled themselves in enduring the climate that in the course of the Glacial Period half the world became accessible to them. As far as is known to-day, the mammoth arrived in Europe earlier than on the northern borders of Asia, where, protected by climatic conditions, its remains are most numerous and best preserved. The number of these gigantic animals must have been very considerable in this Far Northern region for a time, judging from the abundance of bones found there. In Central Europe only a few places are known--such as Kannstatt, Predmost in Moravia, etc.--where the mammoth is found with similar frequency. The mammoth attained its widest distribution in the Interglacial Period. In that period it crossed the Alps, and arrived on the other side, in North Asia, at the border of the “stone-ice” masses of inland ice that were still preserved from the first Glacial Period. The vegetation there was richer then than it is to-day; now only the vegetation of the tundra can exist. Animals found coniferæ, willows, and alders in sufficient quantity to enable them to keep in herds. All the same, we have not to imagine the climate on the borders of the ice to have been “genial,” for from that period originate the mammoth carcases that are found frozen entire in crevasses of the ice-fields. When the new period of cold--the second Glacial Period--began, these Far Northern regions must have become unsuitable for the mammoth owing to the want of food. Von Toll, who has examined the fossil ice-beds and, their relation to the mammoth carcases particularly on New Siberian Islands, says: The mammoths and their contemporaries lived where their remains are found; they died out gradually in consequence of physical geographical changes in the region they inhabited, and through no catastrophe; their carcases were deposited during low temperatures, partly on the river-terraces, and partly on the banks of lakes or on glaciers (inland ice), and covered with mud; like the ice-masses that formed the foundation of their graves, their mummies were preserved to the present day, thanks to the persistent or increasing cold. [Illustration: SKELETON OF A MAMMOTH in the Natural History Museum, South Kensington. ] The woolly-haired mammoth did not survive the second Glacial Period anywhere; in the post-Glacial Period its traces have disappeared. The Drift series of strata are nowhere so clearly exemplified as in the New Siberian Islands, where the Drift stone-ice still forms very extensive high “ice-cliffs,” always covered with a layer of loam, sand, and peat, and having precipices often of great height--in one place seventy-two feet. Embedded in these cliffs of stone-ice have been found the mammoth carcases, which formerly sank into crevices in the ice. These crevices are partly filled up with snow, which has turned into “firn” and finally into ice, but partly also with loam or sand, which are merged above immediately into the strata overlying the stone-ice. In the year 1860 Bojavski, the mammoth-hunter, found a mammoth, with all its soft parts preserved, sticking upright in a crevice in the ice filled with loam; in 1863 it was thrown down, together with the coast-wall that sheltered it, and washed away by the sea. [Illustration: A SURVIVOR OF THE DRIFT PERIOD Only one representative of the great Drift fauna, the musk-ox, has been able to preserve its life to the present day on the larger remnants of its former vast home, such as Greenland and Grinnell Land. ] The Tunguse Schumachow had been more fortunate as early as 1799. During his boating expeditions along the coast, on the look-out for mammoth-tusks, he observed one day, between blocks of ice, a shapeless block which was not at all like the masses of driftwood that are generally found there. In the following year the block had melted a little, but it was only at the end of the third summer that the whole side and one of the tusks of a mammoth appeared plainly out of the ice; the animal, however, still remained sunk in the ice-masses. At last, towards the end of the fifth year, the ice between the ground and the mammoth melted more quickly than the rest, the base began to slope, and the enormous mass, impelled by its own weight, glided down on to the sand of the coast. Here Adams found the carcase in 1806, or as much as the dogs and wild animals had left of it. The whole skeleton, with a portion of the flesh, skin, and hair, has since formed one of the chief ornaments of the collection in the Academy at St. Petersburg. According to Von Toll, who personally visited the site of Bojavski’s discovery, the following profile presented itself there: first the tundra stratum; then an alternation of thin strata of loam and ice; under these a peat-like layer of grass, leaves, and other vegetation, that had been washed together; then a fine layer of sand, with remains of _Salix_, etc., and finally stone-ice. At another place, in Gulf Anabar, in 73° north latitude, Von Toll also found the ground-moraine under a fossil ice-bed, which appears to prove his theory of a Drift region of inland ice, of which the stone-ice beds of New Siberia and Eschscholtz Bay are remains. Of these strata the frozen loam deposits over the stone-ice, containing the willow and the alder, are doubtless Interglacial. Some of the remains of the alder are in such wonderful preservation that there are still leaves and whole clusters of catkins on the branches. The land-mass to which the present New Siberian Islands belong was only dismembered at the end of the Interglacial Period, when colder sea-currents procured an entrance, and the accumulation of snow-masses diminished simultaneously with the sinking of the land, whereas the cold increased. The flora died off, says Von Toll, and the animal world was deprived of the possibility of roaming freely over vast areas. Only one representative of the great Drift fauna, the musk-ox, has been able to preserve its life to the present day on the larger remnants of its former vast home, such as Greenland and Grinnell Land. [Sidenote: Remains of the Ice Age] As we have said, the geological and climatic conditions in all regions of the earth affected by the Glacial Period were closely similar to those just described. In other places the Drift stone-ice has long disappeared, but the ground-moraines of the former inland ice-masses, and the surface-moraines (terminal and lateral) of the former gigantic glaciers, constitute its unobliterated traces. On the moraines of the earlier Glacial Period we find the strata of the Interglacial Period deposited, and on the later moraines of the second (last) Glacial Period lie the remains of the post-Glacial Period, in the course of which a continual increase in the yearly temperature--probably only a few degrees of the thermometer--caused the glaciers to melt and retreat, and opened the way for the return of plants and animals to what had been deserts of snow and ice. The place formerly occupied by the Interglacial and Glacial fauna is then taken by the post-Glacial fauna, which proves considerably different. A number of the most characteristic species of the former sections of the Drift Period are already absent in the earliest post-Glacial deposits; the fauna approaches nearer and nearer in its composition to that of the present day. The inland ice-masses and gigantic glaciers began to melt away, and gradually retired to the present limits of the glaciation that forms the remains of the Glacial Period of the Drift. The animal forms of the beginning of the post-Glacial Period are still living, and the plants characterising this final stage of the Drift Period are still growing on the borders of the ice at the present day. In the post-Glacial Period a few Northern forms--such as the reindeer, lemming, ringed lemming, glutton, zizel, whistling hare, and jumping mouse--still retained for a time their habitats in Central Europe. Part of the Drift fauna--as the horse, wild ass, saiga antelope, and Asiatic porcupine--concentrated again in the Asiatic steppes, from which they had formerly won their territory of the Drift Period; the specific Glacial forms--the reindeer and his above-mentioned companions--followed the retreating ice-masses into the Far North, and even into Polar regions. Another part--the specially Alpine forms, such as the ibex, chamois, marmot, and Alpine hare--migrated with the Alpine glaciers into the high valleys of the Alps, where they could continue the life they had led in the lowlands during the Glacial Period. The mammoth, woolly-haired rhinoceros, and cave-bear are extinct. The present-day mammalian fauna of Europe and North Asia accordingly bears a comparatively young character; during the Drift, and especially in consequence of the Glacial Period, it underwent the most considerable transformations. [Sidenote: Coming of Man upon the Scene] It is in the middle of this great drama of a gigantic animal world struggling and fighting for its existence with the superior powers of Nature, during the Interglacial period of the Drift, that man suddenly appears upon the scene in Europe like a _deus ex machina_. Whence he came we do not know. Did he make his entrance into Europe in company with the Drift fauna that immigrated from Central Asia, or have we to seek his original home in the New World? [Illustration: THE FIRST TENANTS OF THE WORLD: CREATURES THAT LIVED BEFORE MAN This page represents the most typical of the giant creatures that inhabited the world before man. With possibly one exception, they had disappeared before man came and, through long centuries, slowly won dominion over the earth. ] THE WORLD BEFORE HISTORY--II Professor JOHANNES RANKE ] THE APPEARANCE OF MAN ON THE EARTH [Sidenote: The Mystery of a Human Skull] The remains of the Drift fauna are usually found mixed up and washed together in caves and rock-crevices. From the investigation of the caves in Thuringia, Franconia, and elsewhere practically proceeded the first knowledge of the Drift fauna of Central Europe. Here, right among the bones of primeval animals, were also found bones and skulls of man. The strata in which they were discovered appeared undisturbed; that they came into the old burial-places of the Drift fauna subsequently--perhaps by an intentional burial of relatively recent times--was thought to be out of the question. The discovery that became most famous was Esper’s, in one of the richest caves of “Franconian Switzerland,” the Gaillenreuth cave. There, in 1774, Esper found a man’s lower jaw and shoulder-blade at a perfectly untouched spot protected by a stone projection in the cave wall, in the same loam as bones of the cave-bear and other Drift animals. Later, a human skull with some rude potsherds of clay came to light in another place. Esper argued thus: As the human bones (lower jaw and shoulder-blade) lay among the skeletons of animals, of which the Gaillenreuth caves are full, and as they were found in what is in all probability the original stratum, I presume, and I think not without sufficient reason, that these human limbs are of equal age with the other animal fossils. The Cuvier catastrophe theory could not allow this inference; according to that theory it was a “scientific postulate” that man could not have appeared on the earth until the alluvial period, and therefore after the Drift fauna had become extinct. Therefore, in spite of appearances, the human bones must have been more recent; and it was indeed absolutely proved that the skull that Esper had found in the cave with the rude clay potsherds originated from a burial in the floor of the cave. As this was full of remains of Drift animals, the corpse, which had been covered with the earth that had been thrown up in digging the grave, was necessarily surrounded by these remains, and even appeared embedded in them. [Sidenote: The Story of the Caves] It was ascertained that in very early times, but yet long after the Drift Period, the dwellers near by had had a predilection for using the caves as burial-places, so that the fact of human bones coming together with bones of Drift animals in the floor of the same cave is easily explained. Moreover, it was found that from the earliest times down to the present day the caves had been used by hunters, herdsmen, and others as places of shelter in bad weather, as cooking-places, and sometimes even--especially in very early times--as regular dwelling-places for longer periods, so that refuse of all kinds, and often of all ages and forms of civilisation that the land has seen from the Drift Period down to modern times, must have got into the floors of the caves. If these were damp and soft, the remains of every century were trodden in and got to lie deeper and deeper, so that, for instance, the fragments of a cast-iron saucepan were actually found right among the bones of regular Drift animals in a cave in Upper Franconia. [Sidenote: The Caves do not Prove Drift Man] The discoveries of human remains in caves appeared discredited by this, and to be of no value as proofs of the co-existence of man with the Drift fauna. And indeed this position must practically be still taken at the present day: all cave-finds are to be judged with the greatest caution. They in themselves would never have been sufficient to establish the existence of Drift Man, although, according to the general change in scientific thought that led to the overthrow of Cuvier’s theory, Drift Man is now just as much a postulate of science as was formerly the case for the opposite assumption. [Sidenote: Finding the First Drift Man] The first sure proofs were adduced in France by Boucher de Perthes, in the Drift beds of the Somme valley, near Abbeville, at the end of the third decade of the nineteenth century. Fully recognising the inadequacy of proof given by cave-finds, he had sought for the relics of man in the undisturbed Drift beds of gravel and coarse sand that contains the bones of Drift animals, which by their covering and depth precluded all suspicion of having been subsequently dug over. And he was successful. He had argued in exactly the same manner as Esper had formerly done, but with better right. In the stratified Drift formations every period is sharply defined by the layers of differently coloured and differently composed strata horizontally overlying one another. Here the proofs begin. They are irrefutable if it is shown that the relics of man have been there since the deposit. Being no less immovable than this stratum in which they lie, as they came with it, they were likewise preserved with it; and as they have contributed to its formation, they existed before it. [Sidenote: The Overthrow of Cuvier’s Famous Theory] That is the line of thought according to which Boucher de Perthes was able, in 1839, to lay before the leading experts in Paris--at their head Cuvier himself--his discoveries proving the former existence of Drift man. But his demonstrations were not then sufficient to break the old ban of prejudices that were apparently founded on such good scientific bases; his proofs of the presence of man in the Somme valley at the time of the Drift, contemporaneously with the extinct Drift animals, were ridiculed. It was twenty years before these long-neglected discoveries in the Somme valley concerning the early history of man were recognised by the scientific world. This was only made possible by Lyell, whose authority as a geologist had risen above Cuvier’s, placing the whole weight of it on Boucher’s side, after having personally travelled over the Somme valley three times in the year 1859, and having himself examined all the chief places where relics of Drift Man had been discovered. According to Lyell’s description, the Somme valley lies in a district of white chalk, which forms elevations of several hundred feet in height. If we ascend to this height we find ourselves on an extensive tableland, showing only moderate elevations and depressions, and covered uninterruptedly for miles with loam and brick earth about five feet thick and quite devoid of fossils. Here and there on the chalk may be noticed outlying patches of Tertiary sand and clay, the remains of a once extensive formation, the denudation of which has chiefly furnished the Drift gravel material in which the relics of man and the bones of extinct animals lie buried. The Drift alluvial deposit of the Somme valley exhibits nothing extraordinary in its stratification or outward appearance, nor in its composition or organic contents. The stratum in which the bones of the Drift fauna are found intermingled with the relics of man is partly a marine and partly a fluviatile deposit. The human relics in particular are mostly buried deep in the gravel; almost everywhere one has to pass down through a mass of overlying loam with land shells, or a fine sand with fresh-water molluscs, before coming to beds of gravel, in which the relics of Drift Man are found. [Sidenote: Animals of the Ice Age] Everything shows that the relics of man are here in a secondary _situs_, deposited in the same way as the bones of extinct animals and the whole geological material in which everything is embedded. That is the reason why the finds cannot be more exactly dated. They doubtless belong to the general drift, but whether to the Postglacial Period, or the warmer Interglacial Period, cannot be decided. The fauna admits of no absolute limitation, owing to its being mixed from both periods. The mammalia most frequently found in the strata in question are the mammoth, Siberian rhinoceros, horse, reindeer, ure-ox, giant fallow-deer, cave-lion, and cave-hyena. In very similar Drift deposits of the Somme near Amiens traces of man were found beside the bones of the hippopotamus and the elephant. These animals were chiefly prevalent in France and Germany in the Preglacial and Interglacial Periods of the Drift. Part of the animal remains found near Abbeville, particularly those of the cave-lion and cave-hyena, also point to the warmer Interglacial Period; on the other hand, the mammoth, Siberian rhinoceros, and especially the reindeer, appear to indicate with all certainty the second Glacial and Postglacial Periods. The bones of the older Drift animals may have been washed out of other primary _situs_; the reindeer had certainly already taken possession of those parts of France when the relics of man were embedded. [Illustration: Lyell Cuvier Boucher De Perthes THE OVERTHROW OF A FAMOUS THEORY OF THE ORIGIN OF THE EARTH AND MAN When Cuvier was supreme among geologists his theory that the great geological ages ended with sudden catastrophes which annihilated all life, and that all life was then created afresh, was universally accepted. One result of this theory was the disbelief in the existence of man before the Glacial Age. Boucher de Perthes sought to establish the former existence of Drift Man on finding human relics in the Somme Valley; but not until Sir Charles Lyell threw his influence on the side of De Perthes was the Preglacial existence of man admitted, and the long-accepted theory of Cuvier overthrown. ] In spite of the most eager search for similar relic-beds affording sure evidence of Drift Man, only a very few have as yet been discovered that can be placed by the side of those in the Somme valley. Two are in Germany, and are the more valuable as a more exact date can be given to them within the Drift Period. One is near Taubach (Weimar), the other at the source of the Schussen. The one at Taubach belongs to the Interglacial Period, that at the source of the Schussen to the Postglacial Period. The former lies on the moraines of the first Glacial Period, which was followed by the Interglacial Period; the latter on the moraines of the second Glacial Period, which slowly passed into the Postglacial Period. [Sidenote: The Climate of the Ice Age] The Drift relic-bed in the calc-tufa near Taubach lies, as we have said, over the remains of the first Glacial Period, and according to Penck, one of the best authorities on the Drift, belongs to the warmer intermediate epoch between the two great periods of glaciation. The proofs given by the plant and animal remains agree entirely with the proofs given by the conditions of stratification. In the rich fauna found there, animals indicating a cold climate are entirely absent, and a comparison of the whole of the finds proves that at the time when man was present there no kind of arctic conditions can have prevailed. There is no reindeer, no lemming. The roe, stag, wolf, brown bear, beaver, wild boar, and aurochs were at that time inhabitants of these regions, and the only inference they allow is that of a temperate climate. The mollusc fauna, in which also all Glacial forms are absent, also leads to the same conclusion; all that occur are familiar to us from those of the present day in the same district. The fauna would really appear quite modern were it not that a very ancient stamp is imparted to it by several extinct types. With the modern animals enumerated are associated the cave-lion, cave-hyena, ure-elephant, and Merckian rhinoceros, characterising the whole deposit as a distinctly Drift one, which is still further proved stratigraphically by the covering of “loess.” The Taubach relic-bed is a typical illustration of the climatic and biological conditions of the warmer Interglacial Period; the regions of Central Europe, which had been covered with masses of ice in the first Glacial Period, had, after the ice melted, become once more accessible to the banished plants and animals of the Preglacial Period, until they were annihilated, or at least driven definitely from their old habitats by the second Glacial Period. The celebrated relic-bed at the source of the Schussen, near Schussenried, at a little distance from Ulm, brings us--in strong contrast to Taubach--into quite glacial surroundings. It was on the glacier-moraines of the last great glaciation, and belongs, therefore, to that period which must still be reckoned as part of the Drift--the Postglacial Period, which gradually passed into the warmer present period. Under the tufa and peat at the source of the Schussen we find the type of a purely northern climate, with exclusively northern flora and fauna; everything corresponds to climatic conditions such as prevail nowadays on the borders of eternal snow and ice, or begin at 70° north latitude. [Sidenote: Flora and Fauna of the Ice Age] Schimper, one of the best authorities on mosses at the present day, found among the plant-remains under the tufa at the source of the Schussen only mosses of northern or high Alpine forms. Among them was a moss brought from Lapland by Wahlenberg, which, according to Schimper, occurs in Norway near the chalets on the Dovrefjeld, on the borders of eternal snow, and also in Greenland, Labrador, and Canada, and on the highest summits of the Tyrolese Alps and the Sudetic Mountains. It has a special preference for the pools in which the water of the snow and glaciers flows off with its fine sand. There were also found mosses which have now emigrated to cold regions, to Greenland and the Alps. The most numerous animals were the reindeer, and yellow and Arctic foxes, as distinctly Arctic forms; and there were also the brown bear and wolf, a small ox, the hare, the large-headed wild horse--which always occurs in the Drift as the companion of the reindeer--and, lastly, the whistling swan, which now breeds in Spitzbergen or Lapland. There is an absence of all the present animal forms of Upper Swabia, as well as of the extinct Drift animals, either of which would indicate a warmer climate. More decided climatic or biological contrasts than those afforded by the relic-beds at Taubach and the source of the Schussen could not be imagined; here we have with certainty two perfectly different periods before us, but both belonging to the general Drift Era. Although almost all the other places where Drift Man has been found exhibit peculiarities, Taubach and the source of the Schussen seem the best representatives of the two chief types in Europe. Places giving better proof have not yet come to light anywhere in the Old World. [Illustration: REVEALING THE UNKNOWN LIFE OF THE PREHISTORIC PAST A section of the earth, representing excavators in the act of discovering the remains of mammals in a cave in the South of England. Our illustration is reproduced from Buckland’s “Reliquiæ Diluvianæ,” London, 1822. ] [Sidenote: Evidence from South America] At first sight the palæontological strata of South America, in which the presence of man has been proved by Ameghino, appear to give a very different picture. The animal forms occurring here contemporaneously with man deviate to such an extent from those familiar to us in the Drift of the Old World that it required the keen eye and the complete grasp of the whole palæontological material of the world that characterise Von Zittel to recognise and establish the connections here, while the discoverer himself thought that he must date his discoveries of man back to the Tertiary Period. The strata in which the earliest traces of man as yet appear to be proved in South America are the extensive “loess-like” loam deposits of the so-called “pampas” formation in Argentina and Uruguay, with their almost incomparable wealth of animal remains, particularly conspicuous among which are gigantic representatives of edentates that now occur only in small species in South America: Glyptodontia (with the gigantic _Glyptodon reticulatum_) and dasypoda; also of the gravigrada, the giant sloth (_Megatherium americanum_). The toxodontia were also large animals, now extinct. But besides the specifically South American forms, numerous “North American immigrants” also appear in the pampas formation. It was only at the close of the Tertiary Period that the southern and northern halves of America grew together into one continent, and the faunæ of North and South America, so characteristically different, then began to intermingle with one another. The South American autochthons migrate northward; on the other hand, North American types--as the horse, deer, tapir, mastodon, _Felis_, _Canis_, etc.--use the newly-opened passage to extend their range of distribution. The northern animal forms are very conspicuous among the animal world of South America, hitherto cut off from North America and characterised by the above-mentioned wonderful and, in part, gigantic edentates, marsupials, platyrhine apes, etc. Of the great elephantine animals of North America only the mastodon crossed over to South America. In the middle and latest Tertiary formations the genus mastodon is widely distributed over Europe, North Africa, and South Asia. In North America the oldest species of the mastodon appear in the Middle Tertiary (Upper Miocene), but the most species are found in the latest Tertiary (Pliocene) and the Drift (Pleistocene); in South America the mastodon is limited to the time of the pampas formation. Its tusks are long and straight, or slightly curved upward; its lower jaw also possesses two tusks, which project in a straight direction, but are considerably less than the upper tusks in size. From the results of Ameghino’s investigations man appears to have come to South America with these northern immigrants, especially with the mastodon. In Ameghino’s lists of the animals of the pampas formation Von Zittel describes man, like the animal forms enumerated above, as an immigrant from North America, and as a northern type. According to Von Zittel’s statements there is no longer any doubt that the pampas formation, and with it early man, of South America, is to be assigned to the Drift Era; he sums up the case in these words: In South Asia and South America the Tertiary Period is followed by Drift faunæ, which in the main are composed of species still existing at the present day, but yet show somewhat closer relations to their Tertiary predecessors. THE WORLD BEFORE HISTORY--III Professor JOHANNES RANKE ] THE LIFE OF MAN IN THE STONE AGE [Sidenote: Man a Witness of the Flood] The oldest remains affording us knowledge of man are not parts of his body--not the skeleton from which, in the case of primeval animals, we have learned to reconstruct their frame--but evidences of the human mind. Until the discoveries of Boucher de Perthes turned the scale, search had been made in vain among the bones of the fossil fauna for remains of the skeleton of fossil man of undoubtedly the same age; it was not bones, but tools, by which the Abbeville antiquary proved that man had been a “witness of the Flood” in Europe; tools which taught irrefutably that the mental powers of fossil man of the Drift were similar in kind to, if possibly less in degree than, those of living members of mankind. The Drift tools prove that, even in that early epoch to which we have learned from Boucher to trace him back, man was distinctively man. Boucher de Perthes was an expert archæologist, and he knew that in Europe, in a very early period of civilisation, men had made their tools and weapons of stone, as many tribes and races in a backward state of civilisation--for example in South America, the South Sea Islands, and many other places--do at the present day. These stone implements are practically indestructible, and from ancient times manifold superstitions have attached to the curious articles that the peasant turns up out of the earth in ploughing. Such stone weapons were called lightning-stones by the Romans, as they are by country-folk at the present day. Scientific archæology occupied itself with them at an early date. In 1778 Buffon declared the so-called lightning-stones, or thunder-stones, to be the oldest art-productions of primeval man, and as early as 1734, Mahudel and Mercati had pronounced them to be the weapons of antediluvian man. Such views determined the line of thought in Boucher’s researches. From the very beginning he sought, in the undisturbed Drift beds of his home, not so much for the bones of Drift Man as for his tools, which he suspected to be of the form of the lightning-stones, although he knew that, so far as was hitherto known, these belonged to a very much later epoch--that is, specially to the Alluvial or “Recent” Period. His expectations were crowned with success. Deep below the mass of overlying loam and sand, right in the strata of gravel and coarse sand, he found stone tools, which without the slightest doubt had been worked by the hand of man for definite and easily recognisable purposes as implements and weapons. Although to a certain extent ruder, they are practically the same forms as the tools, weapons, and implements of stone that we see in use among so-called “savages” of the present day. It is the tool artificially prepared for a certain purpose that raises man above the animal world to-day, as it did in the time of the Drift. [Sidenote: Drift Man’s Three Kinds of Tools] [Sidenote: The Chief Forms of Tools] Upon his first visit to the relic-beds near Abbeville in the spring of 1859, Lyell had obtained seventy specimens of these stone tools from the chief of them. The tools were all of flint, which occurs in abundance in the chalk of the district, and is still obtained and worked for technical purposes at the present day. The worked stones that Boucher found were termed flint or silex tools, according to the material of which they were made. They occurred in the particular beds, as Lyell expressed it, in wonderful quantities. The famous geologist distinguished three chief forms. The first is the spear-head form, and varies in length from six to eight inches. The second is the oval form, not unlike many stone implements and weapons that are still used as axes and tomahawks at the present day--for instance, by the aborigines of Australia. The only difference is that the edge of the Australian stone axes, like that of the European implements of later periods of civilisation known as thunderbolts or lightning-stones, is mostly produced by grinding, whereas on the stone axes from the drift of the Somme valley it has always been obtained by simply chipping the stone, and by repeated, skilfully directed blows. According to Tylor the stone implements of the old Tasmanians were entirely of Drift form and make, all without traces of grinding, being simply angular stones whose cutting-edge had been sharpened by being worked with a second stone. Some of these stone implements of Drift Man may have been simply used in the hand when the natural form of the stone offered a convenient end, but the majority were certainly fastened in a handle in some way or other, to serve as weapons--spear-heads or daggers--both for war and the chase. Lyell’s second chief form would have been used as an axe for such purposes as digging up roots, felling trees, and hollowing out canoes, or to cut holes in the ice for fishing and for getting drinking water in the winter. In the hand of the hunter and warrior the stone axe also became a weapon. As the third form of stone implements Lyell distinguished knife-shaped flakes, some pointed, others of oval form or trimmed evenly at one end, obviously intended partly as knives and arrow-heads, and partly as scrapers for technical purposes. [Illustration: HOW PREHISTORIC MANKIND IS REVEALED Most of our knowledge of the earliest life of man has been revealed by the excavator. When at a certain depth below the earth’s surface the skeleton of a man is found, surrounded with rude stone weapons, ornaments, and the remains of domestic animals, a whole chapter in the life of Prehistoric Man stands revealed at one glance. Our photograph shows an actual skeleton and grave of the Stone Age, as discovered in the year 1875 near Mentone.] Although there are many variations between the first two chief forms, yet the typical difference indicating the different purpose of their use is always easily recognised in well-finished examples. A large number of very rude specimens have also been found, of which many may have been thrown away as spoiled in the making, and others may have been only rubbish produced in the working. Evans has practically proved that it is possible to produce such stone implements in their remarkable agreement of form without the use of metal hammers. He made a stone hammer by fastening a flint in a wooden handle, and worked another piece of flint with this until it had assumed the shape of the axe form--the second, oval form--of the Drift implements. [Sidenote: Lyell’s Find in the Somme Valley] Lyell draws attention to the fact that, in spite of the relatively great frequency of stone implements, it would be a great mistake to rely on finding a single specimen, even if one occupied himself for weeks together in examining the Somme valley. Only a few lay on the surface, the rest not coming to light until after removing enormous masses of sand, loam, and gravel. As we may presume with Lyell that the larger number of the Drift stone implements of Abbeville and Amiens were brought into their position by the action of the river, this sufficiently explains why so many were found at great depths below the surface; for they must naturally have been buried in the gravel with the other stones in places where the stream had still sufficient force or rapidity to wash stones away. They can, therefore, not be found in deposits from still water, in fine sediment and overflow mud. Bones of Drift Man are absent from the deposits of the Somme valley, in spite of the wonderful abundance of stone implements. The “lower jaw from Moulin-Quignon, near Abbeville,” had been fraudulently placed there by workmen. But proof of the existence of man is undeniably assured by the objects, so unpretentious in themselves, that have been recognised as the work of his hands. When once the recognition of Drift Man, founded on the authority of Lyell, was achieved, search for further relic-beds was made in England and France with success. Yet scarcely one of the newly discovered stations was to be compared to those of the Somme valley as regards purity of stratification and conditions of discovery. The relics of the “earliest Stone Age” or “Palæolithic Period,” as the period of Drift Man was called, frequently came from caves and grottos, whose primary conclusiveness Boucher had rightly doubted. Under these circumstances it was of the greatest importance that in Germany Drift Man was discovered in two places, where not only was the geological stratification just as clear as at Abbeville and Amiens, but where also the relics of Drift Man were found, not in a secondary _situs_, as they were then, but in a primary one. In addition to this the two German relic-beds may be safely assigned to the last two great divisions of the Drift Period, to the warmer Interglacial Period, and to the cold Glacial Period proper, with its Postglacial Period; and their climatic conditions were made clear from the remains of plants and animals found in them. Mercier A WORKER IN THE STONE AGE Making an axehead of flint, like that photographed on the opposite page. From the painting by F. Cormon. ] From the occurrence, in the deposits of the Somme, of reindeer that contain the stone implements of Drift Man, we can not, as we saw, exactly settle in what part of the Drift Era man lived there, whether in the Interglacial Period, to which numerous animal remains found there doubtless belong, or not until the “Reindeer” Period, as the last Glacial and early Postglacial Periods were called, when the reindeer was most largely distributed over France and Central Europe. One is inclined to date man’s habitation of the Somme valley back to the Interglacial Period; but it is certain that the relic-bed near Taubach is the first, and, as far as I can see, the only one hitherto, that has given sure proof of Interglacial Man in Europe. There the oldest vestiges of man in Europe were found that have yet been absolutely proved. We have not hitherto succeeded in Europe in tracing man farther back than the Interglacial Period. Relics of him are hitherto as absent in the older Drift as they are in the Tertiary. [Illustration: A WORKMAN’S TOOL IN THE STONE AGE Flint implement found in Gray’s Inn, London; now in British Museum. ] The Taubach relic-bed also furnished no bones of Drift Man among all the parts of skeletons of Drift animals that we have mentioned. Here, too, as in the Somme valley, the proof of the presence of man is based on the works of his hand and mind. Here, too, stone implements and stone weapons are the chief things to be mentioned. But whereas, in the chalk district of France, flints of every size were to be had in the greatest abundance for the preparation of weapons and tools, corresponding stones are not exactly wanting at the two standard German places, though they occur in limited number and size. It is due to this that the larger forms of flint implements, which are most in evidence in the Somme valley, are absent at Taubach. On the other hand, smaller “knives and flakes”--Lyell’s third form of Drift flint implements--occur here with comparative frequency and variety of form. Next to the usual lancet-shaped knife, worked flint flakes, of triangular prismatic form, with sharp corners, are most numerous at Taubach, and scrapers, chisels, awls, and the chipping-stones with which the stone implements were produced may also be distinguished among other things. The material for the implements was supplied by the older Drift débris of the valley--namely, flint, flinty slate, and quartz porphyry. Besides the stone implements which alone were observed in the Somme valley, still further important relics were found here in their primary _situs_. Above all, numerous finds of charcoal and burnt bones prove that the Drift Men of Taubach not only knew how to kindle fire, but were also accustomed to roast the flesh of the animals they killed in the chase. Stones and pieces of shell limestone also occur which have become reddish and hard from the action of heat. These are to be regarded as the floors and side-walls of the fireplaces on which the food was then and there prepared. The animal bones, especially those that were taken up from around the fireplace, appear in most cases to be remains of meals. This is shown at once by the fact that bones of young representatives of the large beasts of the chase--such as the rhinoceros, elephant, and bear--are very frequent as compared with the rare occurrence of full-grown animals. [Sidenote: Hunters of the Stone Age] [Sidenote: How Drift Man Killed the Great Animals] It appears that in the hunting and capture of animals the young ones were most easily killed, and therefore served chiefly as food. Whenever a large animal was killed, it was probably cut up on the spot by the fortunate hunters, who consumed at once part of its flesh; the trunk was then left at the scene of the killing, while the head, neck, and fore and hind legs, on which was the most muscular flesh, and which were at the same time easier to carry away, were taken to the settlement. This may explain why, among the many large bones of the rhinoceros that have hitherto been found, the ribs and the dorsal and lumbar vertebræ are almost entirely absent. Some of the bones of the beasts of the chase bear the unmistakable traces of man. They are broken in the manner characteristic of “savages” of all ages and climes--for the sake of the marrow, one of the greatest dainties of men living chiefly on animal fare. The broken-off heads of the metatarsal bones of the bison still show particularly clearly the method of breaking. They are broken off transversely exactly where the marrow canal ends, and on all these bones there is a roundish depression, or hole, at the same place--namely, in the middle of their front or back surface, and just where the end of the marrow canal is, therefore about in the centre of the break of the broken-off piece. The hole is a “blow-mark” of one inch in diameter, evidently driven in by force from without, as several well-preserved specimens still show the edges and splinters of bone pressed inward. These splinters and all the breaks are old, and have on the surface the same greasy coating, full of the sand in which they lay, as the bones themselves. The instrument used for breaking the bones in this way might very well have been the lower jaw of a bear with its large canine tooth, as Oscar Fraas has ascertained to have been the case in other places where Drift Man has been found. Such lower jaws were found at Taubach, and the nature and size of the hole and its edges agree with this assumption. The long bones of the elephant and rhinoceros were whole. Drift Man did not succeed in breaking these huge pieces, and where such bones are found broken they are accidental fractures. On the other hand, almost all bones of the bear and bison are intentionally split--in almost all cases transversely, and seldom lengthways. [Sidenote: Drift Man at his Meals] In the Somme valley we have only the flint implements--which, although rude, are very regularly and uniformly made for different recognisable purposes--to tell us of the life and state of Drift Man; but the finds at Taubach afford us a rather closer insight into the conditions of his life and culture. What we had suspected from the first finds is confirmed here. During the Interglacial Period we see near Taubach, on the old watercourse of the Ilm, which had there at that time become dammed up into a kind of pond, a human settlement. This was occupied for a long period, as is proved by the large number of bones, evidently remains of meals, and by the quantity of charcoal. Immediately on the bank were the fireplaces--rude hearths built of the stones obtained without trouble in the neighbourhood. Here the flesh of the beasts of the chase, the bison and the bear, and also the elephant and rhinoceros, was broiled in a crude manner in the hot ashes, as is still done by savages on the level of the Fuegians and primitive tribes of Central Brazil at the present day. For this no utensils are required, a sharpened rod or thin pointed stick being sufficient for turning and taking out the pieces of meat. The ashes that the gravy causes to adhere supply the place of salt and other seasoning. The meat was cut up with the stone knives, and many traces of cuts on the bones may also be attributable to these instruments. For cutting out larger portions a powerful and very suitable instrument was at hand, in the lower jaw of the bear, with its strong canine tooth, which also served for breaking bones to obtain the marrow. In spite of the apparent meanness of the weapons, remains of which we have found, the Drift Men of Taubach were yet able, as their kitchen refuse proves, not only to kill the bison and bear, but also the gigantic elephant and rhinoceros, both young and full grown. [Illustration: REINDEER HUNTING IN THE LATER ICE AGE. After a picture by W. Kranz The reindeer was the most familiar animal of the Later Ice Age, its body supplying food, clothing, and implements for Glacial Man. ] [Illustration: WEAPONS OF THE CHASE USED BY PREHISTORIC MAN A collection of neolithic lance and arrow heads found in Ireland, now to be seen in the British Museum. ] [Sidenote: Drift Man after the Hunt] This shows man to have been then, as he is to-day, master even of the gigantic animal forms which so far surpass him in mechanical strength. It is the mind of man that shows itself superior to the most powerful brute force, even where we meet him for the first time. From the finds in the Somme valley it appears that Drift Man already possessed spear, dagger, and axe, besides the knife, as weapons. There the blades were of stone. The relatively small blades of the Taubach stone implements are, it is true, of the same character as the stone implements of Abbeville and Amiens, but they are chiefly, as we have said, merely knife-like articles, very suitable as blades for knives, scrapers, and daggers, and as arrow-heads, but not strong enough as hunting-weapons for such big game. The hunt must, therefore, have been more a matter of capture in pits and traps, as practised at the present day where similar large types of animals are hunted by tribes armed only with defective weapons. The kitchen refuse also proves that the settlement by the Ilm pond, near Taubach, was a permanent one, to which the hunters returned after their expeditions, bringing their game and trophies so far as they were easily transportable. But there is no trace of domestic animals. They could not have completely disappeared, any more than remains of clay vessels, which are still less destructible than bones, and in this respect may be compared to stone implements. There was no trace of potsherds either. [Sidenote: The Best “Find” of the Ice Age] The finds in the Somme valley and near Taubach are of incalculable importance as sure, indisputable proofs of Drift Man in Europe; but as regards the wealth of information to be derived from them respecting man’s psychical condition in that first period in which we can prove his existence, they are far and away surpassed by the find at the source of the Schussen, which Oscar Fraas, the celebrated geologist, has personally inventoried and described. Fraas has rightly given to his description of this find of Glacial Man--the most important and best examined hitherto--the title “Contributions to the History of Civilisation During the Glacial Period.” The geognostic stratification of the relic-bed on one of the farthest advanced moraines of the Upper Swabian plateau proves that it belongs to the Glacial Period, and that this had already pushed its glacier-moraines to the farthest limit ever reached. In point of time the finds are, therefore, to be placed at the end of the Glacial Period, as it was passing into the Postglacial Period; everything still points to Far Northern conditions of life. The finds at the source of the Schussen are thus decidedly more recent, geologically, than those made at Taubach. They are a typical, or, better, _the_ typical example of the so-called “Reindeer Period” of the end of the Drift. [Illustration: IMPLEMENTS OF THE STONE AGE AND THEIR MAKING The methods of holding a hammer-stone and of making a flint by pressure are illustrated at the top, those of using a chopping tool at the bottom, of this plate. The other objects are spear-heads, axes, and hammers of stone and flint, and javelin-heads of horn, the latter being smooth and barbed. The method of tying a flint chisel to a wooden handle is shown at the right (×). Most of these objects are to be seen in the British Museum. ] From Fraas’s description there seems to be no doubt whatever that the relic-bed, with its remains of civilisation, was perfectly undisturbed, and its palæontological contents plainly show its great geological age. It was perfectly protected by Nature. On the top lies peat, the same that covers the lowlands of the whole neighbourhood for miles, and forms the extensive moorlands of Upper Swabia, on which no other formations are to be seen than the gravel drift-walls thrown up by glaciers of the Drift Period. Under the peat lies a layer of calc-tufa, four to five feet thick, a fresh-water formation from the water-courses that now unite with the source of the Schussen. Under this protecting cover of tufa were the remains of the Glacial Period and Glacial Man. The tufa covered a bed of moss of a dark brown colour, inclining to green, the moss still splendidly preserved. Under this bed of moss was the glacier drift. The moss was dripping full of and intermingled with moist sand. In it were the relics of Glacial Man--all lying in heaps as fresh and firm as if they had been only recently collected. A sticky, dark-brown mud filled the moss and sand and the smallest hollow spaces of antlers and bones, and emitted a musty smell. [Illustration: EARLY DRINKING VESSEL Reindeer’s skull used as drinking vessel by men of the Stone Age. British Museum collection. ] [Illustration: TREASURE-STORES OF PRIMEVAL KNOWLEDGE Such to-day are the mounds of prehistoric rubbish accumulated by the people of the Stone Age. These Danish “kitchen middens” have vastly enriched our knowledge of the remote past. ] Glacial Man had used the place as a refuse-pit. Among the bones and splinters of bone of animals that had been slaughtered and consumed by man, among ashes and charred remains, among smoke-stained hearthstones and the traces of fire, there lay here, one upon the other, numerous knives, arrow-heads, and lance-heads of flint, and the most varied kinds of hand-made articles of reindeer horn. All this was in a shallow pit about seven hundred square yards in extent, and only four to five feet deep in the purest glacier drift, clearly showing that the excellent preservation of the bones and bone implements was solely due to the water having remained in the moss and sand. The bank of moss was like a saturated sponge; it closed up its contents hermetically from the air, and preserved in its ever-damp bosom what had been entrusted to it thousands of years before. Under the peat and tufa at the source of the Schussen we find only the type of a purely Northern climate, with Northern flora and Northern fauna. There are no remains of domestic animals--not even of the dog, nor any bones of the stag, roe, chamois, or ibex. Everything corresponds to a Northern climate, such as begins to-day at 70° north latitude. We see Upper Swabia traversed by moraines and melting glaciers, whose waters wash the glacier-sand into moss-grown pools. We find a Greenland moss covering the wet sands in thick banks; between the moraines of the glaciers we have to imagine wide green pastures, rich enough to support herds of reindeer, which roved about there as they do in Greenland, or on the forest borders of Norway and Siberia, at the present day. Here, also, are the regions of the carnivora dangerous to the reindeer--the glutton and the wolf, and, in the second rank, the bear and Arctic fox. [Illustration: A FAMILY GROUP IN THE STONE AGE It was thus that the Danish kitchen middens illustrated on the opposite page were created. Each family group cast its refuse, in the shape of shells, bones, wood, etc., on the midden near at hand, and these heaps of rubbish in process of time became valuable records of the people’s life, in which the archæologist can read for us the story of the past. ] [Sidenote: History in a Rubbish Heap] According to Fraas, it is on this scene that man of the Glacial Period appears; in all probability, a hunter, invited by the presence of the reindeer to spend some time--probably only the better portion of the year--on the borders of ice and snow. It is true that the relic-bed that tells of his life and doings is only a refuse-pit, which contains nothing good in the way of art productions, but only broken or spoiled articles and refuse from the manufacture of implements. The bulk of the material consists of kitchen refuse, such as, besides charcoal and ashes, opened marrow-bones and broken skulls of game. Not one of the bones found here shows a trace of any other instrument than a stone. It was on a stone that the bone was laid, and it was with a stone that the blow was struck. Such breaking-stones came to light in large numbers. They were merely field stones collected on the spot, particular preference being given to finely rolled quartz boulders of about the size of a man’s fist. Others were rather rudely formed into the shape of a club, with a kind of handle, such as is produced half accidentally and half intentionally in splitting large pieces. Larger stones were also found--gneiss slabs, from one to two feet square, slaty Alpine limes, and rough blocks of one stone or another, which had probably represented slaughtering-blocks, or done duty as hearthstones, as on many of them traces of fire were visible. Where these stones had stood near the fire they were scaled, and all were more or less blackened by charcoal. Smaller pieces of slate and slabs of sandstone blackened by fire may have supplied the place of clay pottery in many respects; for, with all the blackened stones, not a fragment of a clay vessel was found in the layers of charcoal and ashes of the relic-bed. [Sidenote: Making Drift Man’s Tools] The flint implements are of the form familiar to us from Taubach and the Somme valley, being simply chipped, not ground or polished. At the source of the Schussen, also, only comparatively small pieces of the precious raw material were found for the manufacture of stone implements. So that here, too, as at Taubach, Lyell’s third form, the knife or flake, was practically the only one represented. They fall into two groups--pointed lancet-shaped knives and blunt saw-shaped stones. The former served as knife-blades and dagger-blades, and lance-heads and arrow-heads; the latter represented the blades of the tools required for working reindeer horn. The larger implements are between one and a quarter and one and a half inches broad and three to three and a half inches long; but the majority of them are far smaller, being about one and a half inches long and only three-eighths of an inch broad. The various flint blades appear to have been used in handles and hafts of reindeer horn. Numerous pieces occur which can only be explained as such handles, either ready or in course of manufacture. Moreover, owing to the want of larger flints, numerous weapons, instruments, and implements were carved from reindeer horn and bone for use in the chase and in daily life. Fraas has ascertained exactly the technical process employed in producing articles of reindeer horn, and we see with wonder how the Glacial men of Swabia handled their defective carving-knives and saws on the very principle of modern technics. They are principally weapons--for example, long pointed bone daggers, otherwise mostly punchers, awls, plaiting-needles (of wood), and arrow-heads with notched grooves. These may possibly be poison-grooves; other transverse grooves may have served partly for fastening the arrow-head by means of some thread-like binding material, probably twisted from reindeer sinews, as is done by the Reindeer Lapps at the present day; other scratches occur as ornaments. [Sidenote: The Skilled Workman of the Drift] The forms of the bone implements show generally a decided sense of symmetry and a certain taste. For instance, a dagger, with a perforated knob for suspension, and a large carefully-carved fish-hook. Groove-like or hollow spoon-shaped pieces of horn were explained by Fraas to be cooking and eating utensils; probably they also served for certain technical purposes--as for dressing skins for clothing and tents, like the stone scrapers found in the Somme valley. A doubly perforated piece of a young reindeer’s antler appears to be an arrow-stretching apparatus, like those generally finely ornamented, used by the Esquimaux for the same purpose. A branch of a reindeer’s antlers, with deep notches filed in, is declared by the discoverer to be a “tally.” The notches are partly simple strokes filed in to the depth of a twelfth of an inch, and partly two main strokes connected by finer ones. “The strokes,” says Fraas, “are plainly numerical signs--a kind of note, probably, of reindeer or bears killed, or some other memento.” Among the objects found were also pieces of red paint of the size of a nut--clearly fabrications of clayey ironstone, ground and washed, and probably mixed with reindeer fat and kneaded into a paste. The paint crumbled between the fingers, felt greasy, and coloured the skin an intense red. It may have been used in the first instance for painting the body. The Glacial men at the source of the Schussen were, according to the results of these finds, fishermen and hunters, without dogs or domestic animals and without any knowledge of agriculture and pottery. But they understood how to kindle fire, which they used for cooking their food. They knew how to kill the wild reindeer, bear, and other animals of the district they hunted over; their arrows hit the swan, and their fish-hooks drew fish from the deep. They were artists in the chipping of flint into tools and weapons; with the former they worked reindeer horn in the most skilful manner. Traces of binding material indicate the use of threads, probably prepared from reindeer sinews; the plaiting-needle may have been employed for making fishing-lines. Threads and finely-pointed pricking instruments indicate the art of sewing; clothing probably consisted of the skins of the animals killed. Mercier HUNTING FOR FOOD IN THE LATER ICE AGE From the painting by Ferdinand Cormon ] To this material concerning Drift Man, scientifically vouched for, coming from Drift strata that have certainly never been disturbed, other countries have hitherto made no equal contributions really enlarging our view. Yet the numerous places where palæolithic--that is, only rudely chipped--implements of flint, such as were doubtless used by Drift Man, have been found must not remain unmentioned here. We know of them in Northern, Central, and Southern France, in the South of England, in the loess at Thiede, near Brunswick, and in Lower Austria, Moravia, Hungary, Italy, Greece, Spain, Portugal, North Africa, and Russia. [Illustration: IMPLEMENTS OF THE STONE AGE The upper illustrations show handles of celt or stone-cutting instruments and method of hafting; the lower picture is that of a handmill of sandstone. ] [Illustration: A HUT-CIRCLE OF THE BRONZE AGE One of the earliest forms of habitation in Britain. From the British Museum “Guide to the Bronze Age.” ] It is of special importance to note that similar flint tools have also been found along with extinct land mammalia in the stratified drift of the Nerbudda valley, in South India, as the supposition more than suggests itself that Drift Man came to our continent with the Drift fauna that immigrated from Asia. The possibility that man also got from North Asia to North America with the mammoth during the Drift Period can no longer be dismissed after the results of palæontological research. It explains at once the close connection between the build of the American and the great Asiatic (Mongolian) races. [Illustration: REMAINS OF A STONE AGE MANSION These remains of a large pile hut discovered in Germany show that Stone Age Man had made good progress in building. The lower diagram shows a transverse section. ] [Illustration: THE EARLIEST EFFORTS AT BOAT-BUILDING The dug-out canoe, hollowed from a single trunk, was the far-off parent of the ocean-going ship. The upper picture represents a prehistoric canoe found in Sussex and the lower example is taken from a German specimen. ] Stone implements of palæolithic form have been found in Drift strata in North America, and the same applies also, as we have seen, to South America. The best finds there were those made by Ameghino in the pampas formation of Argentina. Here marrow-bones, split, worked, and burnt, and jaws of the stag, glyptodon, mastodon, and toxodon have been repeatedly found along with flint tools of palæolithic stamp; and Santiago Roth, who took part in these researches, supposes that fossil man in South America occasionally used the coats of mail of the gigantic armadillos as dwellings. But the civilisation of South American man is doubtless identical with that of European fossil man--tools and weapons of the stone types familiar in Europe, the working of bones, the use of fire for cooking, and animal food, with the consequent special fondness for fat and marrow. THE WORLD BEFORE HISTORY--IV Professor JOHANNES RANKE ] PRIMITIVE MAN IN THE PAST & THE PRESENT To the picture of Drift Man that has been drawn for us by the discoveries of human activity in deposits of uniform character and sharply defined age, the much richer but far less reliable finds in the bone caves add scarcely any entirely new touches. Von Zittel says: The evidence of the caves is unfortunately shaken by the uncertainty that, as a rule, prevails with regard to the manner in which their contents were washed into them or otherwise introduced, and also with regard to the beginning and duration of their occupation; moreover, later inhabitants have frequently mixed up their relics with the heritage of previous occupants. [Sidenote: First Dwellers in Caves] This doubt strikes us particularly forcibly as regards man’s co-existence with the extinct animals of the earlier periods of the Drift, the Preglacial and Interglacial Periods. On the other hand, the habitation of the caves by man during the Reindeer Period appears in many cases to be perfectly established, and, according to Von Zittel, the oldest human dwellings in caves, rock-niches, and river-plains in Europe belong for the most part to the Reindeer Period--that is, the second Glacial and, in particular, the Postglacial Period. In the caves there is also no domestic animal, and no pottery or trace of potsherds, in the best-defined strata where Drift Man has been found. In the Hohlefels cave, in the Ach valley in Swabia, a new utensil was found in the form of a cup for drinking purposes or for drawing water, made out of the back part of a reindeer’s skull. Also a new tool in the form of a fine sewing-needle with eye, from the long bone of a swan, such as have also been found in the caves of the Périgord. Teeth of the wild horse and lower jaws of the wildcat, which are found in the caves, perforated for suspending either as ornaments or amulets, are also hitherto unknown, it appears, in the stratified Drift. As both animals are at a later period connected with the deity and with witchcraft, one could imagine that similar primitive religious ideas existed among the old cave-dwellers. In the stratum of the Reindeer Period at the Schweizerbild, near Schaffhausen, Nüesch found a musical instrument, “a reindeer whistle,” and shells pierced for use as ornaments. [Sidenote: Drift Man’s Working Materials] The finds in the French cave districts prove that man was able to develop certain higher refinements of life, even during the Drift in the real flint districts--where a very suitable material was at man’s disposal in the flint that lay about everywhere or was easily dug up; which was worked with comparative ease into much more perfect and efficient weapons and implements than those supplied by the wilder stretches of moor and fen of Germany, with their scarcity of flint. If we compare the small, often tiny, knives and flint flakes from the German places with the powerful axes and lance-heads of those regions, it is self-evident how much more laborious life must have been for the man who used the former. What labour he must have expended in carving weapons and implements out of bone and horn, while flint supplied the others with much better and more lasting ones with less expenditure of time and trouble! In this light a wealth of flint was a civilising factor of that period which is not to be under-estimated. In the flint districts not only are the stone implements better worked, answering in a higher degree the purpose of the weapon and the tool, but delight in ornament and decoration is also more prominent. [Sidenote: The Life in the Caves] [Sidenote: Drift Man as Artist] Life in the caves and grottos and under the rock shelters in the neighbourhood of rivers was by no means quite wretched. The remains left in the caves by their former inhabitants give almost as clear an idea of the life of man in those primeval times as the buried cities of Herculaneum and Pompeii do of the manners and customs of the Italians in the first century of the Christian era. The floors of these caves in which men formerly lived appear to consist entirely of broken bones of animals killed in the chase, intermixed with rude implements and weapons of bone and unpolished stone, and also charcoal and large burnt stones, indicating the position of fireplaces. Flints and chips without number, rough masses of stone, awls, lance-heads, hammers, and saws of flint and chert lie in motley confusion beside bone needles, carved reindeer antlers, arrow-heads and harpoons, and pointed pieces of horn and bone; in addition to which are also the broken bones of the animals that served as food, such as reindeer, bison, horse, ibex, saiga antelope, and musk-ox. The reindeer supplied by far the greater part of the food, and must at that time have lived in Central France in large herds and in a wild state, all trace of the dog being absent. [Sidenote: Pictures from the Drift World] Among these abundant remains of culture archæologists were surprised to find real objects of art from the hand of Drift Man, proving that thinking about his surroundings had developed into the ability to reproduce what he saw in drawing and modelling. The first objects of this kind were found in the caves of the Périgord. They are, on the one hand, drawings scratched on stones, reindeer bones, or pieces of horn, mostly very naïve, but sometimes really lifelike, chiefly representing animals, but also men; on the other hand imitations plastically carved out of pieces of reindeer horn, bones, or teeth. Such engravings also occurred on pieces of ivory, and plastic representations in this material have been preserved. On a cylindrical piece of reindeer horn from the cave excavations in the Dordogne is the representation of a fish, and on the shovel-piece of a reindeer’s horn are the head and breast of an animal resembling the ibex. Illustrations of horses give faithful reproductions of the flowing mane, unkempt tail, and disproportionately large head of the large-headed wild horse of the Drift. The most important among these representations are such as endeavour to reproduce an historical event. An illustration of this kind represents a group consisting of two horses’ heads and an apparently naked male figure; the latter bears a long staff or spear in his right hand, and stands beside a tree, which is bent down almost in coils in order to accommodate itself to the limited space, and whose boughs, indicated by parallel lines, show it to be a pine or fir. Connected with the tree is a system of vertical and horizontal lines, apparently representing a kind of hurdlework. On the other side of the same cylindrical piece are two bisons’ heads. Doubtless this picture tells a tale; it is picture-writing in exactly the same sense as that of the North American Indians. Our picture already shows the transition to abbreviated picture-writing, as, instead of the whole animals--horses and bisons--only the heads are given. The message-sticks of the Australians bear certain resemblances; Bastian has rightly described them as the beginnings of writing. If we have interpreted them aright, the finds that have been made, with the tally from the source of the Schussen and the message-stick from the caves of the Dordogne, place the art of counting, the beginnings of writing, the first artistic impulses, and other elements of primitive culture right back in the Drift period. [Sidenote: The Emerging of the Human Mind] “None of the animals whose remains lie in the Drift strata,” says Oscar Fraas, “were tamed for the service of man.” On the contrary, man stood in hostile relation to all of them and only knew how to kill them, in order to support himself with their flesh and blood and the marrow of their bones. It was not so much his physical strength which helped man in his fight for existence, for with few exceptions the animals he killed were infinitely superior to him in strength; indeed it is not easy, even with the help of powder and lead, to kill the elephant, rhinoceros, grizzly bear, and bison, or to hunt down the swift horse and reindeer. It was a question of finding out, with his mental superiority, the beast’s unguarded moments, and of surprising it or bringing it down in pits and snares. All the more wonderful does the savage of the European Drift Period appear to us, “for we see that he belongs to the first who exercised the human mind in the hard battle of life, and thereby laid the foundation of all later developments in the sense of progress in culture.” And yet, in the midst of this poor life, a sense of the little pleasures and refinements of existence already began to develop, as proved by the elegantly carved and decorated weapons and implements, and there were even growing a sense of the beauty of Nature and the power of copying it. The bone needles with eyes and the fine awls are evidences of the art of sewing, and the numerous scrapers of flint and bone teach us that Drift Man knew how to dress skins for clothing purposes, and did it according to the method still used among the Esquimaux and most northern Indians at the present day. Spinning does not seem to have been known. On the other hand Drift Man knew how to twist cords, impressions and indentations of which are conspicuous on the bone and horn implements; on which also thread-marks were imitated as a primitive ornament. Pottery was unknown to Drift Man. Indeed, even to-day the production of pottery is not a commonly felt want of mankind. The leather bottle, made of the skin of some small animal stripped off whole without a seam, turned inside out as it were, takes the place of the majority of the larger vessels; on the other hand, liquids can also be kept for some time in a tightly-made wicker basket. Mercier PRIMITIVE NATURE FOLK ENGAGED IN FISHING From the painting by Ferdinand Cormon. ] The art of plaiting was known to Drift Man. This is shown by the ornaments on weapons and implements, the plaiting-needle from the find at the source of the Schussen, and the hurdlework represented on the message-stick mentioned above, which may be either a hurdle made of boughs and branches or a summer dwelling house. To these acquirements, based chiefly on an acquaintance with serviceable weapons and implements, is added the art of representing natural objects by drawing and carving. This results in the attempt to retain historical _momenta_ in the form of abridged illustrations for the purpose of communicating them to others--incipient picture-writing. The tally shows the method of representing numbers--generally only one stroke each, but also two strokes connected by a line to form a higher unit. Of the art of building not a trace is left to us apart from the laying together of rough stones for fireplaces; nor have tombs of that period of ancient times been discovered. Mercier EARLY AGRICULTURISTS, WITH IMPLEMENTS OF BONE, STONE, AND BRONZE From the painting by Ferdinand Cormon. ] The civilisation of Drift Man and his whole manner of life do not confront the present human race as something strange, but fit perfectly into the picture exhibited by mankind at the present day. Drift Man nowhere steps out of this frame. If a European traveller were nowadays to come upon a body of Drift men on the borders of eternal ice, towards the north or south pole of our globe, nothing would appear extraordinary and without analogy to him; indeed it would be possible for him to come to an understanding with them by means of picture-writing, and to do business with them by means of the tally. Mercier AN EMIGRATION OF THE GAULS IN THE BRONZE AGE From the painting by Ferdinand Cormon. ] The manner of life led by man beyond the borders of higher civilisation, especially under extreme climatic conditions, depends almost exclusively on his outward surroundings and the possibility of obtaining food. The Esquimaux, who, like Drift Man of Central Europe in former times, live on the borders of eternal ice with the Drift animals that emigrated thither,--the reindeer, musk-ox, bear, Arctic fox, etc.--are restricted, like him, to hunting and fishing, and to a diet consisting almost entirely of flesh and fat; corn-growing and the keeping of herds of domestic animals being self-prohibitive. Their kitchen refuse exactly resembles that from the Drift. Before their acquaintance with the civilisation of modern Europe they used stone and bone besides driftwood for making their weapons and implements, as they still do to a certain extent at the present day, either from preference or from superstitious ideas. Their binding material consisted of threads twisted from reindeer sinews, with which they sewed their clothes and fastened their harpoons and arrows, the latter resembling in form those of Drift Man. They knew no more than he the arts of spinning and weaving, their clothes being made from the skins of the animals they hunted; pots were unknown and unnecessary to them. [Illustration: PRIMITIVE ART OF OUR OWN DAY The picture-writing of the American Indians in our own day offers an interesting parallel to that of the primitive peoples of the remotest past. The Pawnees decorate their buffalo robes with such drawings as these, representing a procession of medicine men, the foremost giving freedom to his favourite horse as a sacrifice to the Great Spirit. ] It has often been thought that we should have a definite criterion of the period if it could be proved that fresh mammoth ivory was employed at the particular time for making implements and weapons, or ornaments, carvings, and drawings. There can be no doubt that when Drift Man succeeded in killing a mammoth he used the tusks for his purposes. But on the borders of eternal ice, where alone we could now expect to find a frozen Drift Man, no conclusion could be drawn from objects of mammoth ivory being in the possession of a corpse to determine the great age of the latter. For the many mammoth tusks which have been found and used from time immemorial in North Siberia, on the New Siberian Islands, and in other places, are absolutely fresh, and are even employed in the arts of civilised countries in exactly the same way as fresh ivory. Under the name of “mammoth ivory” the fossil tusks dug up by ivory-seekers, or mammoth-hunters, form an important article of commerce. The same conditions as many parts of Northern Siberia still exhibit at the present day prevailed over the whole of Central Europe at the end of the Glacial Period and the beginning of the Postglacial Period. Here man lived on frozen ground on the borders of ice-fields with the reindeer and its companions, as he does to-day in Northern Asia, and here, too--as he does there to-day--he must have found the woolly-haired mammoth preserved by the cold in the ice and frozen ground. The Drift reindeer-men of Central Europe presumably searched for mammoth tusks just as much as the present reindeer-men in North Asia. The great field of mammoth carrion at Predmost was, therefore, a very powerful attraction, not only for the beasts of prey--chief among them wolves--but also for man. [Illustration: THE EARLIEST ART: MANKIND’S FIRST EFFORTS IN PICTURE-MAKING These illustrations are of engravings on stone and bone and scratchings on rocks made by prehistoric man, chiefly in France. The figures of the reindeer and those of the mammoth and the bison, the two latter found at Dordogne, are astonishingly good, and indicate genuine power of draughtsmanship at a remote period of human life. ] [Sidenote: Drift Man Compared with Modern Man] In France especially many primitive works of art of the “Ivory Epoch” have been found, and even the nude figure of woman is not wanting; but no proof is given that these carvings belong to the time when the mammoth still lived. Much sensation has been caused by an engraving on a piece of mammoth ivory representing a hairy mammoth with its mane and strongly-curved tusks. This illustration has been taken as unexceptionable proof that the artist of the Drift Period who did it saw and portrayed the mammoth alive. But could the mammoth hunter Schumachow--the Tunguse who, in 1799, discovered, in the ice of the peninsula of Tumys Bykow at the mouth of the Lena, the mammoth now erected in the collection at the St. Petersburg Academy [see page 123]--have pictured the animal otherwise when it was freshly melted out of the ice? And the Madelaine cave in the Périgord, where the piece of ivory with the picture of the mammoth was found, certainly belongs to the Reindeer Period. Had we not independent proofs that Drift Man lived in Central Europe--for instance, at Taubach--with the great extinct pachydermata, neither the finds in the “loess” near Predmost, nor the articles of ivory, nor the illustration of the mammoth itself, could prove it. They furnish absolute proof of the existence of Drift Man only back to the Reindeer Period. To decide whether a corpse frozen in the stone-ice belonged to a Drift Man, the examination of the corpse itself, its skull, bones, and soft parts, would no more suffice than clothing, implements, and ornament. For at least so much is confidently asserted by many palæontologists, that all the skulls and bones hitherto known to have been ascribed to Drift Man by the most eminent palæontologists, geologists, and anthropologists, cannot be distinguished from those of men of the present day. Von Zittel, the foremost scholar in the field of palæontology in Germany, says: The only remains of Drift Man of reliable age are a skull from Olmo, near Chiana, in Tuscany; a skull from Egisheim, in Alsace; a lower jaw from the Naulette cave near Furfooz, in Belgium; and a fragment of jaw from the Schipka cave in Moravia. This material is not sufficient for determining race, but all human remains of reliable age from the drift of Europe, and all the skulls found in caves, agree in size, form, and capacity with _Homo sapiens_, and are well formed throughout. In no way do they fill the gap between man and ape. [Illustration: PRIMITIVE PEOPLE OF TO-DAY Until they came in touch with European travellers the Esquimaux were in precisely the same condition as Drift Man: they were living in the Ice Age. They are but little more advanced now, and the difference between them and prehistoric men is slight. This is a group of young Esquimau women. ] “On the other hand,” writes Dr. Chalmers Mitchell, “a large majority of modern anatomists and palæontologists accept the antiquity of such skulls as the Neanderthal specimen, and agree that these point to the existence of a human race inferior to any now existing. This race comprised powerfully-built individuals, with low foreheads, prominent, bony ridges above the eyes, and retreating chins. The radius and ulna were unusually divergent, so that the forearms must have been heavy and clumsy. The thigh-bones were bent and the shin-bones short, so that the race must have been bow-legged and clumsy in gait.” [Sidenote: A Type Between Man and Ape?] “The intermediate position of these primitive types has received extraordinary confirmation by the discovery of what may truly be called the link, no longer missing, between man and the apes. In 1894, Dr. Eugene Dubois discovered in the Island of Java in a bed of volcanic ashes containing the remains of Pliocene animals the roof of a small skull, two grinding-teeth, and a diseased femur. These remains indicate an animal which, when erect, stood not less than 5 ft. 6 in. high. The teeth and thigh-bones were very human, and the skull, although very human, had prominent eyebrow ridges like those of the Neanderthal type, and a capacity of about 1,000 cubic centimetres--that is to say, much greater than that of the largest living apes, and falling short by about 100 cubic centimetres of the largest skull capacities of existing normal human beings. This creature, regarded at first by some anatomists as a degenerate man, by others as a high ape, has now been definitely accepted as a new type of being, intermediate between man and the apes and designated as _Pithecanthropus erectus_.” There is no doubt that Asia, Europe, North Africa, and North America, so far as their ice-covering allowed of their being inhabited, form one continuous region for the distribution of Palæolithic Man, in which all discoveries give similar results. In this vast region the lowest and oldest prehistoric stratum that serves as the basis of historical civilisation is the homogeneous Palæolithic stratum. In the Drift Period, Palæolithic Man penetrated into South America, as into a new region, with northern Drift animals. In Central and South Africa and Australia, Palæolithic Man does not yet seem to be known. All the more important is it that in Tasmania Palæolithic conditions of civilisation existed until the middle of the last century. [Illustration: THE HOMES OF PRIMITIVE PEOPLE OF THE PRESENT DAY There are people still living in dwelling-places of prehistoric type. This photograph of Esquimau stone and turf huts, in Greenland, shows exactly the kind of dwellings used by prehistoric men in the Ice Age. ] [Illustration: THE GRADUAL EXTINCTION OF PRIMITIVE PEOPLES The Yukaghirs, natives of Siberia, a division of the Mongolic family, were formerly a wide-spread race, and, according to their national tradition, were so numerous that “the birds flying over their camp fires became blackened with smoke.” The Jesup Expedition found them reduced to 700 in number. Hunger had forced some of them to cannibalism and suicide. They are a primitive people, but considerably superior to the Esquimaux. ] [Illustration: A CREATURE BETWEEN APE AND MAN The skull of the Fossil Ape-man found in 1894, in the island of Java; restored by Dr. Eugene Dubois. ] [Sidenote: Backward Races of Europe] The palæontology of man has hitherto obtained good geological information of the oldest Palæolithic culture-stratum of the Drift in only a few parts of the earth, and only in Tasmania does this oldest stratum appear to have cropped out free, and still uncovered by other culture strata, down to our own times. Otherwise it is everywhere overlaid by a second, later culture-stratum of much greater thickness, which, although opened up in almost innumerable places, is not spread over the whole earth as is the Palæolithic stratum. As opposed to the earliest Stone Age of the Drift, which we have come to know as the Palæolithic Period, this has been called the Later Stone Age or Neolithic Period. The Neolithic Period is also ignorant of the working of metals; for weapons and implements, stone is the exclusive hard material of which the blades are made. But geologically and palæontologically the two culture-strata are widely and sharply separated. As regards Europe, and a large part of the other continents, the second stratum of the culture of the human race still lies at prehistoric depth. But in other extensive parts of the earth the stratum of Neolithic culture was not covered by other culture-strata until far into the period of written history. Even a large part of Europe was still inhabited by history-less tribes of the later Stone Age at the time when the old civilised lands of Asia and of Africa, and the coasts of the Mediterranean, had everywhere--on the basis of the same Neolithic elements, with the increasing use of metals--already risen to that higher stage of civilisation which, with the historical written records of Egypt and Babylonia, forms the basis of our present chronology. When these civilised nations came into direct contact with the more remote nations of the Old World, they found them, as we have said, still, to a certain extent, at the Neolithic stage of civilisation, just as, when Europeans settled in America, the great majority of the aborigines had not yet passed the Neolithic stage, at which, indeed, the lowest primitive tribes of Central Brazil still remain. Australia, and a large part of the island world of the South Sea, had not yet risen above the Neolithic stage (Tasmania, probably, not even above the Palæolithic) when they were discovered. There the Stone Age, to a certain extent, comes down to modern times; likewise in the far north of Asia, in Greenland, in the most northern parts of America, and at the south point of the New Continent among the Fuegians. The men of the later Stone Age are the ancestors of the civilised men of to-day. Classical antiquity among Greeks and Romans had still a consciousness of this, at least partly; it was not entirely forgotten that the oldest weapons of men did not consist of metal, but of stone, and even inferior material. The worked stones which the people then, as now, designated as weapons of the deity, as lightning-stones or thunderbolts, were recognised by keener-sighted men as weapons of primeval inhabitants of the land. [Sidenote: What the Kitchen Middens Tell Us] The “kitchen middens” on the Danish coasts mark places of more or less permanent settlement, consisting of more or less numerous individual dwellings. From these middens a rich inventory of finds has been made, affording a glimpse of the life and doings of those ancient times. The heaps consist principally of thousands upon thousands of opened shells of oysters, cockles, and other shellfish still eaten at the present day, mingled with the bones of the roe, stag, aurochs, wild boar, beaver, seal, etc. Bones of fishes and birds were also made out, among the latter being the bones of the wild swan and of the now extinct great auk, and, what is specially important in determining the geological age of these remains, large numbers of the bones of the capercailzie. Domestic animals are absent with the exception of the dog, whose bones, however, are broken, burnt, gnawed in the same way as those of the beasts of the chase. Everything proves that on the sites of these middens there formerly lived a race of fishers and hunters, whose chief food consisted of shellfish, the shells of which accumulated in mounds around their dwellings. Proofs of agriculture and cattle-rearing there are none; the dog alone was frequently bred not only as a companion in the chase, but also for its flesh. The state of civilisation of the old Danish shellfish-eaters was not quite a low one in spite of its primitive colouring, and in essential points was superior to that of Palæolithic Man. Not only had they tamed a really domestic animal, the dog, but they made and used clay vessels for cooking and storing purposes. The cooking was done on fireplaces. They could work deer-horn and bone well. Of the former hammer-axes with round holes were made, and of animal bones arrow-heads, awls, and needles, with the points carefully smoothed. Small bone combs appeared to have served not so much for toilet purposes as for dividing animal sinews for making threads, or for dressing the threads in weaving. [Illustration: EUROPE IN THE ICE AGE The map illustrates the extent of the Ice Age in Europe. It will be noticed that in England the ice-cap did not extend south of the position of London though it occurred much further south in the mountain regions of the Pyrenees, the Alps, Tyrol, the Carpathians and the Caucasus. The dark portions of the map represent the extent of the ice. ] [Sidenote: Drift Man and His Adversaries] In the way of ornaments there were perforated animal teeth. The fish remains found in the middens belong to the plaice, cod, herring, and eel. To catch these deep-sea fish the fishermen must have gone out to sea, which implies the possession of boats of some kind. Nor was only small game hunted, but also large game. Ninety per cent. of the animal bones occurring in the shell-mounds consist of those of large animals, especially the deer, roe, and wild boar. Even such dangerous adversaries as the aurochs, bear, wolf, and lynx were killed, likewise the beaver, wildcat, seal, otter, marten, and fox. The very numerous fragments of clay vessels belong partly to large pot-like vessels without handles and with pointed or flat bottoms, and partly to small oval bowls with round bottoms. All vessels were made with the free hand of coarse clay, into which small fragments of granitic stone were kneaded; as ornament they have in a few cases incisions or impressions, mostly made with the finger itself on the upper edge. The great importance of the Danish middens in the general history of mankind is due to the fact that their age is geologically established, so that they can serve as a starting-point for chronology. It is to Japetus Steenstrup that the early history of our race owes this chronological fixing of an initial date. [Sidenote: The First Elements of Civilisation] The earliest inhabitants of the North of Europe during the Stone Age, as recorded by these kitchen-middens of the Danish period, were scarcely superior to Palæolithic Man in civilisation, judging from outward appearances. But a closer investigation taught us that, in spite of the poverty of their remains, a higher development of civilisation is unmistakable. And this superiority of the Neolithic over the Palæolithic Epoch becomes far more evident if we take as our standard of comparison, not the poor fisher population, who probably first reached the Danish shores as pioneers, but the Neolithic civilisation that had been fully developed in sunnier lands and followed closely upon these trappers or squatters. Next to hunting and fishing, cattle-breeding and agriculture are noticeable as the first elements of Neolithic civilisation, and in connection with them the preparation of flour and cooking; and as technical arts, chiefly carving and the fine working of stone, of which weapons and the most various kinds of tools were made; with the latter wood, bone, deer-horn, etc., could be worked. The blades are no longer sharpened merely by chipping, but by grinding, and are made in various technically perfect forms. Special importance was attached to providing them with suitable handles, for fixing which the stone implement or weapon was either provided with a hole, or, as in America especially, with notches or grooves. [Sidenote: The Mental Life of Ancient Days] In addition to these, there are the primitive arts of man--the ceramic art, spinning, and weaving. In the former, especially, an appreciation of artistic form and decoration by ornament is developed. The ornament becomes a kind of symbolical written language, the eventual deciphering of which appears possible in view of the latest discoveries concerning the ornamental symbolism of the primitive races of the present day. Discoveries of dwellings prove an advanced knowledge of primitive architecture; entrenchments and tumuli acquaint us with the principles of their earthworks; and the giant chambers, built of colossal blocks of stone piled upon one another, prove that the builders of those times were not far behind the much-admired Egyptian builders in transporting and piling masses of stone. The burials, whose ceremonies are revealed by opened graves, afford a glimpse of the mental life of that period. From the skulls and skeletons that have been taken from the Neolithic graves, science has been able to reconstruct the physical frame of Neolithic Man, which has in no way to fear comparison with that of modern man. Of the ornaments of the Stone Age the most important and characteristic are perforated teeth of dogs, wolves, horses, oxen, bears, boars, and smaller beasts of prey. How much in favour such ornaments were is proved by the fact that even imitations or counterfeits of them were worn. Numerous articles of ornament, carved from bone and deer-horn, were universal: ornamental plates and spherical, basket-shaped, square, shuttle-like, or chisel-shaped beads were made of these materials and formed into chains. [Illustration: THE ICE AGE IN THE PRESENT DAY: AN ESQUIMAU WATCHING A SEAL HOLE] In the Swiss lake-dwellings of the Stone Age have been found skilfully carved ear-drops, needles with eyes, neat little combs of boxwood, and hairpins, some with heads and others with pierced side protuberances. Remains of textile fabrics, even finely twilled tissue, and also leather, were yielded by the excavations of the lake-dwellings of that period, so that we have to imagine the inhabitants adorned with clothes of various kinds. [Sidenote: Man’s First and Oldest Animal Friend] What raises man of the later Stone Age so far above Palæolithic Man is the possession of domestic animals and the knowledge of agriculture. As domestic animals of the later Stone Age we have proof of the dog, cow, horse, sheep, goat, and pig. Among the animals that have attached themselves to man as domestic, the first and oldest is undoubtedly the dog. It is found distributed over the whole earth, being absent from only a few small islands. Among many races the dog was, and is still, the only domestic animal in the proper sense of the word. This applies to all Esquimau tribes, to the majority of the Indians of North and South America, and to the continent of Australia. We have no certain proofs that Palæolithic Man possessed the dog as a domestic animal. In the Somme valley, at Taubach, and at the source of the Schussen, bones of the domestic dog are absent. And yet, among Drift fauna in caves remains of dogs have been repeatedly met with, which have been claimed to be the direct ancestors of the domestic dog. The dog’s attachment to man may have taken place at different times in different parts. Man and dog immigrate to South America with the foreign Northern fauna simultaneously--in a geological sense--during the Drift. In Australia, man and dog (dingo), as the most intimate animal beings, are opposed to an animal world that is otherwise anomalous and, to the Old World, quite antiquated; probably man and dog also came to Australia together. We know of fossil remains of the dingo from the Drift, but no reliable finds have yet proved the presence of man during that period. [Sidenote: The Dog in the Stone Age] In the later Stone Age the dog already occurs as the companion of man wherever it occurs in historic times. In Europe its remains have been found in the Danish kitchen-middens, in the northern Neolithic finds, in the lake-dwellings of Switzerland, in innumerable caves of the Neolithic Period, in the terramare of Upper Italy, etc. It was partly a comparatively small breed, according to Rütimeyer similar to the “wachtelhund” (setter) in size and build. Rütimeyer calls this breed the lake-dwelling dog, after the lake-dwellings, one of the chief places where it has been found. Like all breeds of animals of primitive domestication, the dog at this period, according to Nehring, is small--stunted, as it were. With the progress of civilisation the dog also grows larger. [Sidenote: Great Value of the Dog to Man] In the later prehistoric epochs, beginning with the so-called “Bronze” Period, we find throughout almost the whole of Europe a rather larger and more powerful breed with a more pointed snout--the Bronze dog--whose nearest relative seems to be the sheep-dog. At the present day the domestic dog is mostly employed for guarding settlements and herds and for hunting. In the Arctic regions the Esquimaux also use their dogs, which are like the sheep-dog, for personal protection and hunting; they do particularly good service against the musk-ox, while the wild reindeer is too fast for them. But the Esquimau dog is chiefly used for drawing the sledge, and, where the sledge cannot be used, as a beast of burden, since it is able to carry fairly heavy loads. In China and elsewhere, as formerly in the old civilised countries of South America, the dog is still fattened and killed for meat. So that the domestic dog serves every possible purpose to which domestic animals can be put, except, it seems, for milking, although this would not be out of the question either. The dog was also eaten by man in the later Stone Age, as is proved by the finds in his kitchen refuse. The reindeer is now restricted to the Polar regions of the Northern Hemisphere--Scandinavia, North Asia, and North America, whereas in the Palæolithic Period it was very numerous throughout Russia, Siberia, and temperate Europe down to the Alps and Pyrenees. It does not seem ever to have been definitely proved that the reindeer existed in the Neolithic Period of Central and Northern Europe, although according to Von Zittel it lived in Scotland down to the eleventh century and in the Hercynian forest until the time of Cæsar. The earliest definite information we appear to have of the tamed reindeer, which at the present day is a herd animal with the Lapps in Europe, and with the Samoyedes and Reindeer Tunguses in Asia, is found in Ælian, who speaks of the Scythians having tame deer. Oxen at present exist nowhere in the wild state, while the tame ox is distributed as a domestic animal over the whole earth, and has formed the most various breeds. In the European Drift a wild ox, the urus, distinguished by its size and the size of its horns, was widely distributed, and it still lived during the later Stone Age with the domestic ox. In the later prehistoric ages, and even in historic times, the urus still occurs as a beast of the forest. [Sidenote: The Taming of the Wild Horse] In the later Stone Age the horse, too, is no longer merely a beast of the chase, but occurs also in the tame state. During the Drift the horse lived in herds all over Europe, North Asia, and North Africa. From this Drift horse comes the domestic horse now found all over the earth. Even the wild horses of the Drift exhibit such considerable differences from one another that, according to Nehring’s studies, these are to be regarded as the beginning of the formation of local breeds. The taming and domestication of the wild horse of the Drift, which began in the Stone Age, led to the domestic horse being split up later into numerous breeds. The old wild horse was comparatively small, with a large head; a similar form is still found here and there on the extensive barren moors of South Germany in the moss-horse, or, as the common people call it, the moss-cat. At the present day the genus of the domestic horse falls, like the ox, into two chief breeds--a smaller and more graceful Oriental breed, and a more powerful and somewhat larger Western breed with the facial bones more strongly developed. The horse of the later Stone Age of Europe exhibits only comparatively slight differences from the wild horse; it is generally a small, half-pony-like form with a large head, evidently also a stunted product of primitive breeding under comparatively unfavourable conditions. Two species extant in the Stone Age still live wild on the steppes of Central Asia at the present day; one of them also occurs as a fossil in the European Drift, although only rarely. That the ass occurred in the European Drift is probable, but not proved. It has not yet been found in the Neolithic Period of Europe. [Sidenote: Did the Horse come from Asia?] A survey of the palæontology of the domestic animals shows that they come from wild Drift species which--at any rate, as regards the ox, horse, and dog--are now extinct, so that these most important domestic animals now exist only in the tame state. Some of the domestic animals came from Asia, and, according to Von Zittel, were imported into Europe from there; this applies to the peat-ox and the domestic goat and pig. The Asiatic origin of the domestic horse and sheep is probable, but not proved; the sheep is found wild in South Europe as well as in Asia. The tarpan, a breed of horse very similar to the wild horse, lives in herds independent of man on the steppes of Central Asia. This has been indicated as being probably the parent breed of the domestic horse, and the origin of the latter has accordingly also been traced to Asia. One thing is certain: a considerable number of animal forms that co-exist with man in Europe at the present day--for instance, almost all the forms of our poultry and the fine kinds of pigs and sheep--have originally come from Asia. Our investigations show a similar state of things even in the Neolithic Period. In the North of Europe, which has furnished us with our standard information regarding the Neolithic culture-stratum, the certain proofs that have hitherto been found of agriculture and the cultivation of useful plants having been practised at that time (to which civilisation owes no less than to the breeding of useful tame animals) consist not so much of plant remains themselves as of stone hand-mills and spinning and weaving implements, which indicate the cultivation of corn and flax. [Sidenote: History in the Lake Dwellings] Our chief knowledge of Neolithic agriculture and plant culture has been furnished by the lake-dwellings, especially those of Switzerland, which have preserved the picture of the Neolithic civilisation of Central Europe, sketched for us, as it were, in the North, in its finest lines. So far we can prove the cultivation of the following useful plants in the later Stone Age; their remains were chiefly found, as we have said, well preserved in the Stone Age lake-dwellings of Switzerland, which have been described in classical manner by Oswald Heer. Of cereal grasses Heer determined, in the rich Stone Age lake-dwellings of Wangen, on Lake Constance, and Robenhausen, in Lake Pfäffikon, three sorts of wheat and two varieties of barley--the six-rowed and two-rowed. Flax was also grown by Neolithic Man. This was, it seems, a rather different variety from our present flax, being narrow-leaved, and still occurs wild, or probably merely uncultivated, in Macedonia and Thracia. Flax has also been found growing wild in Northern India, on the Altai Mountains, and at the foot of the Caucasus. [Illustration: THE DEVELOPMENT OF THE HORSE The horse which was common in the Stone Age was a wild ancestor of our own domestic horse, but not quite so large or so strong as the average well-bred creature familiar in our modern life. Its remotest ancestor was the Hyracotherium, or Orohippus, while an intermediary stage was that of the Hypparion, or Protohippus, in which, as shown in the diagram, the change from the foot to the hoof had advanced to a very great extent.] The common wheat occurring in the lake-dwellings of the Stone Age is a small-grained but mealy variety; but the so-called Egyptian wheat with large grains also occurs. [Sidenote: Gardening in the Stone Age] Traces of regular gardening and vegetable culture are altogether wanting. Some finds, however, seem to indicate primitive arboriculture, apples and pears having been found dried in slices in the lake-dwellings of the Stone Age; there even appears to be an improved kind of apple besides the wild-growing crab. But although they are chiefly wild unimproved fruit-trees of whose fruit remains have been found, we can imagine that these fruit-trees were planted near the settlements, and the great nutritious and health-giving properties of the fruit, as a supplement to a meat fare, must have been all the more appreciated owing to the lack of green vegetables. The various wild cherries, plums, and sloes were eaten, as also raspberries, blackberries, and strawberries. Beechnut and hazelnut appear as wild food-plants. The original home of the most important cereals--wheat, spelt, and barley--is not known with absolute certainty; probably they came from Central Asia, where they are said to be found wild in the region of the Euphrates. The real millet came from India; peas and the other primeval leguminous plants of Europe, such as lentils and beans, came likewise from the East, partly from India. So that, apart from flax, which probably has a more northern home, the regular cultivated plants of the Stone Age of Central Europe--cereal grasses, millet, and lentils--indicate Asia as their original home. We have therefore a state of things similar to that observed in the case of the domestic animals. [Sidenote: Beginning of the Potter’s Art] The potter’s art was probably entirely unknown to Palæolithic Man, for in none of the pure Drift finds have fragments of clay vessels been found. So where clay vessels or fragments of them occur, they appear as the proof of a post-Drift period. On the other hand, pottery was quite general in the Neolithic Age of Europe. Still, the need of clay vessels is not general among all races of the earth even at the present day; up to modern times there were, and still are, races and tribes without pots. From their practices it is evident that the European Stone men of the Drift could also manage to prepare their food, chiefly meat, by fire without cooking vessels. The Fuegians lay the piece of meat to be roasted on the glowing embers of a dying wood fire, and turn it with a pointed forked branch so as to keep it from burning. Meat thus prepared is very tasty, as it retains all the juice and only gets a rind on the top, and the ashes that adhere to it serve as seasoning in lieu of salt. On a coal fire not only can fish be grilled, stuck on wooden rods, but whole sheep can be roasted on wooden spits, precisely as people have the dainty of roast mutton in the East. To these may be added a large number of other methods of roasting, and even boiling, without earthen or metal vessels, which are partly vouched for by ethnography and partly by archæology, and some of which, like the so-called “stone-boiling,” are still practised at the present day. [Sidenote: No Perfect Pottery in the Stone Age] Although, according to this, pottery is not an absolute necessary of life for man, yet it is certain that even those poorly equipped pioneers who first settled in Denmark in the Pine Period, in spite of their having an almost or quite exclusive meat fare, had clay pottery in general use for preparing their food, and probably also for storing their provisions. As we have already shown, the remains that have been preserved in the kitchen-middens are the oldest that have been found in Denmark. Simple and rude as the numerous potsherds that occur may appear, they are of the highest importance on account of the proof of their great age. Unfortunately, as we have already seen, not a single perfect vessel has come to light. The fragments are very thick, of rough clay with bits of granite worked in, and are all made by hand without the use of the potter’s wheel. The pieces partly indicate large vessels, some with flat bottoms, and others with the special characteristic of pointed bottoms, so that the vessel could not be stood up as it was. Smaller bowls, frequently of an oval form, also occurred with rounded bottoms, so that they also could not stand by themselves. It is very important to note that on these fragments of pottery we find only extraordinarily scanty and exceedingly simple ornamental decorations, consisting merely of incisions, or impressions made with the fingers, on the upper edge. [Illustration: MAN’S FIGHT WITH THE GIANT ANIMALS OF THE ANCIENT WORLD From the painting, “The Slaughter of a Mammoth,” by V. M. Vasnetsov, now in the Russian Historical Museum at Moscow. ] We shall see how far this oldest pottery of the Stone Age is distinguished by its want of decoration from that of the fully-developed Stone Age. But it is very important to notice that this rudest mode of making clay vessels, which we here see forming the beginning of a whole series that rises to the highest pitch of artistic perfection, remained in vogue not only during the whole Stone Age, but even in much later times. [Sidenote: Stone Age Potter’s Handwork] It is true that in the fully developed neolithic Stone Age of Europe the clay pottery is also all made by hand, without the potter’s wheel, the oldest and rudest forms still occurring everywhere, as we have said; but besides these a great variety is exhibited in the size, form, and mode of production of the pottery. The clay is often finer, and even quite finely worked and smoothed, and the vessels have thin sides and are burnt right through. The thick fragments are generally only burnt outside, frequently only on one side, and so much that the clay has acquired a bright red colour, whereas the inside, although hard, has remained only a greyish black. We have numerous perfectly preserved vessels of the later Neolithic Age. They are frequently distinguished by an artistic finish and beauty of form, and on their surfaces we find ornaments incised or imprinted, but rarely moulded on them, which, although the style is only geometrical, cannot be denied a keen sense of beauty and symmetry. The clay vessels also show the beginning of coloured decoration. The incised strokes, dots, etc., are often filled out with white substance (chalk or plaster), which brings the patterns out into bold ornamental relief from the black or red ground of the surface. After that it is no wonder that pottery advanced to the real coloured painting of the vessels during the Neolithic Period, at least in some places. [Sidenote: Growth of Artistic Taste] On these vessels the handle now appears, in its simplest form as a wart-like or flatter projection from the side of the vessel, pierced either vertically or horizontally with a narrow opening just large enough to admit of a cord being passed through. Other handles, just like those in use at the present day, are bowed out broad, wide, and high for holding with the hand. These generally begin quite at the top, at the rim of the vessel, and are continued from there down to its belly, whereas the first-mentioned are placed lower, frequently around the greatest circumference of the vessel. There is no doubt whatever that in the main these clay vessels were made on the spot where we find their remains at the present day. This easily explains the local peculiarity that we recognise in various finds, by which certain groups may be defined as more or less connected with one another. Different styles may be clearly distinguished by place and group. But, this notwithstanding, wherever we meet with neolithic ceramics, they cannot conceal their homogeneous character. In spite of all peculiarities this general uniform style of the ceramics of the Stone Age, which we can easily distinguish and determine even under its various disguises, goes over the whole of Europe. [Sidenote: The Proofs of Man’s Mental Development] In finds that lie nearer to the old Asiatic centres of civilisation and to the coasts of the Mediterranean--as, for instance, at Butmir--the vessels are in part better worked, and the ornaments are richer and more elegant, and the spirals more frequent and more regular, and are sometimes moulded on, and sometimes, as we have mentioned, even painted in colour. But the general character remains unmistakably Neolithic, and may be found not only on the European coasts of the Mediterranean and the islands of the Ægean Sea, but in certain respects also in Mesopotamia and Egypt. The oldest Trojan pottery also exhibits unmistakable points of agreement with it. Not only the stone weapons and implements, but, as far as we can see, even the remains of the oldest ceramics, show that uniform development of the culture of the Neolithic Period which proves a like course of mental development in mankind. [Illustration: THE WORLD BEFORE HISTORY--V Professor JOHANNES RANKE] THE HOME LIFE OF PRIMITIVE FOLK [Sidenote: What the Lake Dwellings Tell] A picture, of unequalled clearness of delineation, of the general conditions of the life and culture of Central European Man during the Neolithic Period, was given, according to the results of the celebrated researches of Ferdinand Keller and his school of Swiss archæologists, by the lake-dwellings in the Alpine lowlands. Whereas in cave districts the caves and grottos often served the men of the later Stone Age as temporary and even as permanent winter dwellings, in the watery valleys of Switzerland the Neolithic population built its huts on foundations of piles in lakes and bogs. In that period we have to imagine the Alpine lowlands still extensively covered with woods and full of wild beasts; at that time the huts standing on piles in the water must have afforded their inhabitants a security such as scarcely any other place could have given. The first founders and inhabitants of settlements of pile-dwellings in Switzerland belong to the pure Stone Period. In spite of their lake-dwellings the old Neolithic men of Switzerland appear to have possessed almost all the important domestic animals, but they also knew and practised agriculture. They lived by cattle-rearing, agriculture, hunting, and fishing, and on wild fruit and all that the plant world freely offered in the way of eatables. Their clothing consisted partly of skins, but partly also of stuffs, the majority of which seem to have been prepared from flax. [Sidenote: Beginnings of a Social Order] The endeavour of the settlers to live together in lasting homes protected from surprises, and in large numbers, is an unmistakable proof that they were aware of the advantages of a settled mode of life, and that we have not to imagine the inhabitants of the pile-dwellings as nomadic herdsmen, and still less as a regular race of hunters and fishermen. The permanent concentration of a large number of individuals at the same point, and of hundreds of families in neighbouring inlets of the lakes, could not have taken place if there had not been through all the seasons a regular supply of provisions derived principally from cattle-rearing and agriculture, and if there had not existed the elements of social order. Even the establishment of the lake-settlement itself is not possible for the individual man; a large community must have here worked with a common plan and purpose. Herodotus describes a pile-village in Lake Prosias, in Thracia, which was inhabited by Pæones, who defended it successfully against the Persian general Megabazos. The scaffold on which the huts were built stood on high piles in the middle of the lake; it was connected with the bank only by a single, easily removable bridge. Herodotus says: The piles on which the scaffolds rest were erected in olden times by the citizens in a body; the enlargement of the lake-settlement took place later, according as it was necessitated by the formation of new families. [Sidenote: The Lake Dweller At Home] According to the large number of lake-dwellings of the Stone Age in the Alpine lowlands, and according to the large quantity of products of primitive industry that have been found there, centuries must have elapsed between the moment when the first settlers rammed in the piles on which to build their dwellings and the end of the Stone Period. The huts of the settlements of the Stone Age were partly round and partly quadrangular, and, like the pile-hut discovered by Frank near Schussenried, were divided into two compartments--one for the cattle, and the other, with a hearth built of stones, for the dwelling of man. The floor of the hut was made of round timber with a mud foundation, and perhaps also with a mud flooring; in Frank’s hut the walls were formed of split tree-trunks, standing vertically with the split sides turned inward, firmly put together between corner posts. The round huts had walls of roughly intertwined branches, covered with clay inside and out; of this clay-plaster numerous pieces have been preserved, hardened by fire, with the marks of the branches. The pile huts of the lakes were connected with the water by block or rung ladders. Victor Cross found such a ladder in one of the oldest stations; it consisted of a long oak pole provided at fairly regular intervals with holes in which the rungs were inserted. [Sidenote: First Traces of Textiles] [Sidenote: In a Stone Age Kitchen] Of special importance in estimating the degree of civilisation attained by the lake-dwellers of the Stone Age are the remains of spinning and weaving implements and of webs and textile fabrics, plaited work, etc. Flax has been found wound on the implements made of ribs, that we mentioned above as flax combs; we have also mentioned the fixing of blades with flax, or threads made of it, and the numerous wide and narrow nets made of threads. For spinning the thread, spindles were used just like those of the present day, a spindle-stick of wood being fastened into a spinning-whorl made of stone, deer-horn, or clay. The distaff was probably not yet known; a loom has not yet been found, either; but numerous weaver’s weights, which served for spinning the threads, have been. Excellent webs, some of them twilled, were produced, of which we have many fragments. Remains of mats and baskets prove that those were manufactured from the materials still employed at the present day. Corn was baked into a kind of bread consisting of coarsely ground grains. The millstones that were used for grinding the corn are found in large numbers. They are rather worn, hollowed slabs of stone, and smaller flat stones rounded on the top, with which the grains of corn were crushed on the larger slabs. Some of the kitchen utensils we find already much improved. Large and small pots for storing purposes, earthen cooking pots, and dishes, and large wooden spoons and twirling-sticks--the latter probably for churning--have been preserved. Vessels like strainers served for making cheese; they are pots in whose sides and bottoms a number of small holes were made for pouring off the whey from the cheese. Here, in the fully developed Neolithic Period we find the early inhabitants of Switzerland to be a settled agricultural and farming population. Although hunting and fishing still furnished an important part of their food, so that in some places even more deer bones have been found among the cooking remains than bones of the ox, yet the milk, cheese, and butter of the cows, sheep, and goats, the flesh of these and of the hog, and bread and fruit, already formed the basis of their subsistence. [Illustration: A PRIMITIVE STYLE OF DWELLING STILL WIDESPREAD IN SAVAGE LANDS The lake dwellings still in use in New Guinea, illustrated in this reproduction from an old work, D’Urville’s “Voyage of the Astrolabe,” are exactly like the lake dwellings of prehistoric Europe. ] [Sidenote: Man Learning the Art of Living] The results of cave research are almost as rich and varied as the results yielded by the study of the lake-dwellings in their bearing on the Neolithic stratum. Where there is a Drift stratum in the cave-earth the confusion of Palæolithic and Neolithic objects can, as we have said, scarcely be avoided. But there are numerous grottos and small caves in which the Neolithic stratum is the oldest, so that mistakes are out of the question. In a large number of such places in the cave district of the Franconian-Bavarian Jura the conditions under which finds have been made in the Neolithic stratum have proved almost as pure and unmixed as in the lake-dwellings. The cave-dwellers of the later Stone Age in the Franconian Jura were, like the Swiss lake-dwellers of the Stone Age, mainly a pastoral race. They possessed all the important domestic animals that the latter possessed--dog, cow, horse, sheep, goat, pig--and likewise practised agriculture, or, at any rate, flax-growing; at the same time hunting and fishing formed a considerable part of their means of subsistence. So that, not only on artificial pile-works on the shores of lakes, but also on the banks of South German rivers, there formerly lived a race which, although still mainly restricted to hunting and fishing, and using no metal, but exclusively stone and bone tools, already practised cattle-breeding and primitive agriculture, and was able to increase the means of existence afforded it by Nature by the first technical arts--by the chipping and grinding of stone instruments, bone carving, and, above all, pottery-making, tanning, and the arts of sowing, weaving and plaiting. [Sidenote: Beginning of Weaving and Knitting] Of most importance, as showing the state of civilisation of the Neolithic rock-dwellers, are the numerous articles carved from bone that must be looked upon as instruments for weaving and net-knitting. For the latter purpose there were large, finely-smoothed bone crochet-needles, some of them carved from the rib of a large ruminant. The handle-end is smoothed by use, and the end with the hook is rounded from the same cause. The end is frequently perforated, so that it might be hung up. Still more numerous were shuttles of various forms. According to the numerous finds of perforated clay weaver’s weights, the loom, like that of the lake-dwellers, must have been like the ancient implement that, according to Montelius, was in use on the Faröe Islands a comparatively short time ago. Spinning-whorls are very numerous, being partly flat, round discs of bone pierced in the centre, and partly thick bone rings or large beads of bone and deer-horn and flat burr-pieces of deer-antlers. It was formerly thought that the Neolithic Europeans did not possess the arts of engraving and carving animals and human figures which the Palæolithic Men had understood in such conspicuous manner. The progress of research has now produced more and more proof that in the later Stone Age the arts of carving and engraving had not died out. We have the celebrated amber carvings of the later Stone Age from the Kurisches Haff, near Schwarzort, some of which probably served a religious purpose; those of ivory, bone, stalactite, etc., from the caves of France and the Polish Jura; the figures from Butmir, and other evidences. [Sidenote: Fortified Settlements in Stone Age] In Italy, in Lombardy, and Emilia, another group of settlements of the Stone Age has been found, which again exhibit the civilization and all other signs of the later Stone Age, and in many respects more closely resemble the lake-dwellings than do the cave-dwellings. These are the “terramare,” whose inhabitants, however, had already to some extent advanced to the use of bronze. A sharp division of strata into habitation of the pure Stone Age and habitation of the Metal Age has not yet been made. The huts stood on pile-work on dry land, the piles being six to ten feet high; the whole settlement was fortified with trench and rampart, generally with palisades, and was of an oblong or oval plan. Besides many natural and artificial caves in Italy the dwelling-pits, which may formerly have borne the superstructure of a hut, also belong to the pure Stone Age. [Illustration: LAKE-DWELLERS RETURNING FROM THE HUNT IN THEIR DUG-OUT CANOES From a painting by Hippolyte Coutau, in the Geneva Museum. ] [Sidenote: Strange Homes of Early Man] Such dwelling-pits of the Stone Age seem to have been distributed all over Europe. Burnt wall-plaster with impressions of interwoven twigs, has frequently been found near or in the pits, doubtless indicating hut-building. In Mecklenburg, where the dwelling-pits were first carefully examined by Liesch, they have a circular outline of ten to fifteen yards, and are five to six and a half feet deep. At the bottom of the pit lie burnt and blackened stones, hearthstones, charcoal, potsherds, broken bones of animals, and a few stone implements, the latter being mostly found in larger numbers in the vicinity of the dwellings. The same circular dwelling-pits of the Stone Age are found in France. Smaller hearth-pits were recently found in very large numbers in the Spessart, in Bavaria, with hundreds of stone hatchets and perforated axe-hammers, some of the former being very finely made of jadeite. [Sidenote: America before History] During the Neolithic Period dwellings were frequently made on heights, and it seems that even at that time they were to a certain extent walled round and fortified. Such settlements are numerous all over Southern and Central Germany, in Austria-Hungary, especially in the coast-country, and in Italy and France. Many of these stations belong purely to the Stone Age; indeed, the majority were inhabited already during the Stone Age, and furnish the typical Neolithic relics familiar from the foregoing. On the other hand, they continue to be inhabited even in the later metal periods, and in some cases right down to modern times. The rock near Clausen, in the Eisack valley, in the Tyrol, on which the large Säben monastery now stands, was a mediæval castle, and during the times of the Romans a fortified settlement called Sobona stood there; and when excavations were made in 1895, for adding new buildings to the monastery, a well-ground stone hatchet of the later Stone Age came to light. On many hills in Central Germany are found traces of the ancient presence of men who lived on them or assembled on them for sacrificial feasts; the earth is coloured black by charred remains and organic influences, and this “black earth on heights and hills” contains frequently, as we have said, the traces of Neolithic men. In Italy, many finds on such heights--for instance, those made on the small castle-hill near Imola--seem to exhibit that stage of the Stone Age that is missing in the terramare, and that precedes the beginning of the Metal Age of the terramare, but corresponds to it in every essential except in the possession of metal. But the view that is opened up is still wider. The prehistoric times of the New World also exhibit a Neolithic stage, corresponding to that of Europe, as the basis of the further development of the ancient civilised lands of America. And where a higher civilisation did not develop autochthonously in America, European discoverers found the Neolithic civilisation still in active existence, as they did in the whole Australian world. Accordingly in these vast regions, which have never risen above the Stone Age of themselves, the same stage of civilisation which in the old civilised lands belongs to a grey, immemorial, prehistoric period, here stands in the broad light of historic times. The study of modern tribes in an age of stone throws many a ray of light on the conditions of the prehistoric Stone Age; and this study, on the other hand, shows us that the primitive conditions of civilisation of those tribes stand for a general stage of transition in the development of all mankind. [Sidenote: The Foundations of Society] The lake-dwelling stations, and the land settlements resembling them, prove of themselves how far the culture of the early inhabitants of Europe was advanced even in that ancient period which was formerly imagined to be scarcely raised above half-animal conditions. Such structures could not be erected unless men combined into large social communities, which is indeed indicated by the very fact of the number of dwellings that were crowded into a comparatively small space. For the first ramming-in of the pile-works a large number of men working together on a common plan was absolutely necessary. The same applies to the construction of the artificial islands, protected by pile-works and partly resting on piles, termed “crannoges” by Irish archæologists, and to the Italian villages called “terramare,” which likewise once rested on piles and were protected by ditches. From the extent of the pile-works we are able to estimate the number of the former inhabitants of the settlements supported by them. Quite as clear an idea of the number of the former inhabitants is also given by the early circumvallations on the tops of hills and shoulders of rock, which were likewise made and inhabited during the Stone Age. The co-operation of a large number of men for a common purpose is also shown in the often huge stone structures to which, on account of the size of the stones employed in their construction, the name “megalithic” structures, or gigantic stone structures, has been given. In Northern Europe they, too, belong to the Stone Age proper. The majority of these gigantic structures were originally tombs; the principle on which they are built is often repeated even in far less imposing tombs. [Illustration: THE FAMOUS GIANT CHAMBER NEAR ROSKILDE IN DENMARK That the men of the later Stone Age had developed a considerable degree of culture is proved by such remains as these. The erection of these giant chambers must have called for a vast amount of co-operation, skill, and ingenuity. The means whereby the massive stones were placed into position, and so fixed to withstand the shocks of thousands of years, have not yet been satisfactorily explained by archæology. ] The stone blocks of which these gigantic structures are piled now often lie bare. Large stones placed crosswise, which represent, as it were, the side-walls of a room, support a roof of one or several “covering-stones” of occasionally colossal size. For the erection of these in their present position without the technical resources at the disposal of modern builders, human strength appears inadequate; in popular opinion only giants could have made such structures. Some of the stones are really so large, and the covering-stones especially so enormous, that these buildings have defied destruction, for thousands of years, by their very weight. In the time of their construction these giants’ graves were mostly buried under mounds. They were the inner structures of large tumuli, in which the reverence of the men of the Stone Age once buried its heroes. One of the finest “giant’s chambers” is probably that near Öm, in the neighbourhood of Roskilde, in Denmark. The building material consists merely of erratic stone blocks of enormous size. The rough blocks were mostly set up by the side of one another, without any further working, so as to support one another as far as possible; at the same time all of them, as Sophus Müller observes, are slightly inclined inward, so that they are kept more firmly in position by their own weight. The stones thus erected, forming the parallel side-walls of the whole structure, stand so far apart that a huge erratic block, reaching from one wall to the other, could be placed on them as a roof. The distance between the side-walls of the giant’s chambers attains a maximum of eight to nine feet; the covering-stones placed on them are some ten to eleven feet long. The pressure of the covering-stones from above helps considerably to hold the whole structure together. In order to distribute the pressure of the covering-stones regularly, smaller stones were carefully inserted under the wall-stones where they had to stand on the ground. How exactly these proportions of weight were judged is proved by the fact that these structures of heavy and irregular stones, resting on their natural, differently shaped sides and edges, have held together until the present day. The inner walls of the chambers were made as carefully as possible. Where, as on the outside, the rough and irregular form of the stone block projects, either the naturally smooth side was turned inward or the roughness was chipped off. [Illustration: THE MARVELLOUS MEMORIALS OF THE STONE AGE AT CARNAC IN BRITTANY On the plain near the little town of Carnac, in Brittany, stand eleven thousand immense monoliths in eleven rows, erected probably for religious purposes in the Stone Age. ] These are the beginnings of a real architecture, seen also in the regular wedging with small stones of the spaces left between the wall-stones and covering-stones and between the wall-stones themselves. These small stones were frequently built in, in regular wall-like layers. Sandstone was often used for the purpose, being more easily split into regular pieces, which gave this masonry a still more pleasing appearance. The number of stone blocks used for the wall-sides varies according to the size of the giant’s chambers, as does also the number of covering-stones. For smaller chambers, with six to nine wall-stones, two or three covering-stones were required. But far larger stone chambers occur, as many as seventeen wall-stones having been counted. Such large chambers require a whole row of covering-stones beside one another. The door-opening often shows a special regard for architectonics. The two door-post stones are rather lower than the other wall-stones; on them a stone was laid horizontally, which kept them apart and distributed the pressure of the covering-stone equally on both posts. Very often there was also a stone as a threshold. Leading to the door is a low passage, made in similar manner to the chamber, but of far smaller stones. The passage is only high enough to allow one to creep through, whereas the chamber itself is about as high as a man, so that one could stand upright in most of them. Larger stone chambers are rarely without this passage, and from it such grave-structures have been named “passage-graves.” Besides the building-in of small stones, the holes still remaining between the stones were also coated over on the outside with mud to keep the rain-water from soaking in; mud was also frequently used for making a rough plaster floor for the chamber if the natural floor could not be made level enough. On the floor is frequently found a compact layer of small flints, or a regular pavement of flat stones, often rough-hewn, or roundish stones fitting one another as nearly as possible, which were then probably also covered with a thick layer of mud. [Illustration: “THE MERCHANTS’ TABLE”: AN IMMENSE DOLMEN ERECTED IN THE STONE AGE Archæologists are not entirely agreed as to the purpose of these dolmens. They were more likely graves, or chambers associated with religious rites, than residences. This example is at Locmariaquer, near Carnac, in Brittany. ] So that in these giant’s chambers we have real buildings, which imply high technical accomplishments and have preserved for us the usual form of the dwellings of those early times. In what manner the huge covering-stones were placed on the side-walls of the giant’s chambers is a problem still unsolved. Doubtless many hands were occupied on such structures; and the history of building teaches us that with the proper use of human strength--as, for instance, in ancient Egypt--great weights can be raised and placed in position with very simple tools--round pieces of wood as rollers, ropes, and handspikes. [Illustration: INTERIOR OF THE “MERCHANTS’ TABLE” This is the interior of the above dolmen. It will be seen that the earth has slowly risen a great height since it was erected, nearly covering the dolmen, thus indicating immense age. The principal supporting stone is covered with sculpture.] Some of these giant’s chambers, which were originally enclosed in mounds or barrows, are still preserved at the present day, and splendidly too. Very often the chamber was quite covered with earth outside; it then formed the centre of what was generally a circular barrow, often regular small hills ten to fifteen feet high and frequently over ninety feet in circumference. [Illustration: A PALACE UNDER A CLIFF: A REMARKABLE MONUMENT OF THE STONE AGE IN CLIFF PALACE CAÑON, COLORADO This is perhaps the most noteworthy of all the remains of the cliff dwellers, and indicates how considerable was the culture of those early people in America. ] The corpses were buried, not cremated. They were frequently in a crouching attitude, or that of a sleeper lying sideways with the legs drawn up to the body. The smaller graves often represent single interments; the larger or largest ones are mostly family tombs, in which numerous corpses were interred one after the other at different times. But this repeated use of the graves is found also with smaller ones, and even with stone cists. Only the last corpse then lies in a normal position, while, through the repeated opening of the grave and the later interments, the skeletons belonging to previously interred corpses appear more or less disturbed or intentionally put aside. The skulls of the corpses interred in the Neolithic graves are well formed, their size indicating a very considerable brain development. The corpses were no bigger than the present inhabitants of the same districts, and the form of the head corresponds partly with that of the present population of those countries. Nor do the skeletons otherwise differ from those of modern men. In America, also, gigantic structures were erected by the aborigines who lived in the Stone Age, to commemorate and to protect their dead. They consist partly of large mounds of stones and earth, which are likewise often regular small hills, and partly of stone structures reminding one of the giants’ chambers. The majority of the mounds were doubtless mainly sepulchral; others may have been temple-hills or sacrificial mounds, defensive works or observatories. The objects buried with the occupants belong mostly to the Neolithic Period, and consist chiefly of stone weapons and tools, some rude, but others finely worked and polished. Some are of pure natural copper, which was beaten into shape cold with stone hammers. Besides these, and ornaments and pottery, an American specialty is found in the form of tobacco-pipes carved from stone, some of which give interesting representations of men and animals; this seems to prove that tobacco also played a part in the American funeral rites of those times. The graves of the Neolithic Period not only indicate that mankind generally was endowed with the same gifts as regards the first principles of the art of building, but they also afford us a glimpse of the mental life of that period of civilisation which at a more or less distant period was spread over the whole earth. What is so characteristic is the affectionate care for the corpse, for whose protection no amount of labour and trouble appeared too great. We can have no doubt that this reverence was based on a belief in the immortality of the soul--a belief which we find also at the present day among the most backward and abandoned “savages.” That the prehistoric men of the Stone Age held this belief is proved by the ornaments, weapons, implements, and food placed with the dead for use in the next world. Their burial customs certainly express a kind of worship of departed souls which has played and still plays so important a part in the religious ideas of all primitive peoples, and is one of the oldest fundamental notions common to mankind. G. Nordenskiöld HOW STONE AGE MAN WAS BURIED Photograph of an actual skeleton, in position of burial, taken from a prehistoric mound grave in North America. ] [Illustration: THE STRANGE RELIGION OF THE STONE AGE: A DRUID CEREMONY AT STONEHENGE A vivid illustration, from an old print, of the purposes of the mysterious stone circles common in Celtic countries ] [Illustration: THE WORLD BEFORE HISTORY--VI Professor JOHANNES RANKE] WHEN HISTORY WAS DAWNING The discovery of Drift Man, his distinction from man of the later Stone Age, the investigation of the Palæolithic and Neolithic strata of culture of Europe and of the whole earth, and the scientific reconstruction of the earliest forms of civilisation based on these, are due solely to the natural-science method of research. It was only when the exact methods of palæontology and geology had been brought to bear with all their rigour on the study of ancient man by savants schooled in natural science that solid results were obtained. On this sure foundation the science of history now continues building, and uses, even for the later periods, so far as recorded information is not available, and to supplement it, the same methods of palæontology and natural science which were applied so successfully to the earliest stages of the evolution of mankind. [Sidenote: Time-Table of Prehistoric Periods] The first point is to collect the relics of the periods of the evolution of culture which follow on the later Stone Age, and to separate them according to geological strata, uninfluenced by those older pseudo-historic fancies by which the deepening of our historical knowledge has so long been hindered. By carefully separating and tracing the earth’s strata till we come to those that furnish remains of times recorded in history, it has been possible to establish first a relative chronology of the so-called later prehistoric periods of Central Europe, whose offshoots pass immediately into recorded history. By digging, after the same method of palæontological science, through stratum after stratum in the oldest centres of culture, especially in the Mediterranean countries, and by arranging the products by strata--uninfluenced by historical hypotheses--after the same natural-science method of research which has produced such remarkable results in Central Europe, the most surprising conformity in the evolution of culture in widely remote regions has been shown. It was found that in the Mediterranean countries, and also in Egypt and Babylonia, forms of culture already belong to the time of real history which were first recognised in Central Europe as preliminary prehistoric stages of historical strata; so that it was possible also to establish an absolute historical chronology for those instead of the relative prehistoric one. [Sidenote: Europe’s Prehistoric Night] Thus times which, as regards Central Europe, were hitherto wrapped in prehistoric night are enlightened by history. Although, as regards Central and Northern Europe, we cannot name the peoples who were the bearers of those forms of culture, and although we disdain to give them a premature nomenclature of hypothetical names, yet their conditions of life and culture and the progressive development of these, in manifold contact and intercourse with neighbouring and even far remote historic peoples and periods, have risen from the darkness of thousands of years; and their relation in time to the latter has been recognised. Thus prehistoric times have themselves become history. The historical account of every single region has henceforth to begin with the description of the oldest antiquities of the soil that tell of man’s habitation, in order thereby to obtain the chronological connection with the evolution of the history of mankind generally. That is the palæontological method of historical research. [Sidenote: Landmarks of Early Culture] The palæontology of man has proved the Stone Age to be a general primary stage of culture for the whole human race. All further general progress in culture was affected by the discovery of the art of metal-working--the extraction of the metals from their ores and the casting and forging of them. The later and latest eras of culture are the Metal Ages, as opposed to the Stone Ages. It is not the use of metal in itself, but the above-mentioned metallurgical arts, that form the criterion of the advance of culture beyond the bounds of the Stone Age. Where, as in some parts of America, native copper was found in abundance, this red malleable mineral could probably be worked in the same way as stone, without any further progress necessarily developing therefrom. The same may apply to meteor-iron, which is said to have been used for arrows, together with stone points, by American tribes who were otherwise in the age of stone and but poorly civilised. [Illustration: From stone to metallic form Growth of the stop-ridge Growth of the wings THE TRANSITION FROM STONE TO IRON This series of diagrams, reproduced from specimens in the British Museum, by permission of the Trustees, shows how the stone axehead was used as the model for the metal axe or celt, and how that in turn was modified as workers gained experience in the use of the metal ] In civilised lands it is chiefly metal casting and the forging of the heated metal which have made it possible to produce better weapons and tools and more valuable ornaments. The worked metals are first copper, then the alloy of copper and tin that bears the name of classical bronze, and to these are soon added gold and--especially in districts rich in the metal, as in Spain--silver. Later on the extraction of iron from its ores and the forging of that metal are discovered. According to this course of metallurgical progress the first metal period is distinguished as the Bronze Period, which is begun by a Copper Period lasting more or less long in different places. The second or later metal period is the Iron Period, in which we are living at the present day. In the course of time, by gradually displacing bronze and copper from the rank of metals worked for weapons and tools, this Iron Age has developed to its present stage. In Central Europe the pile-dwellings in the lakes of Western Switzerland again present us with specially clear and uninterrupted series of illustrations of the progress of culture from the Stone Age to the Iron Age. Ending the Stone Age, we find first a period of transition, in which, while stone continued to be principally employed, a few ornaments, weapons, and tools of metal began to be used. This metal is at first almost exclusively copper, with only very little bronze; iron is quite absent. Copper objects have been found in Western Switzerland by Victor Gross, most extensively in Fenel’s lake-dwelling station, which otherwise still belongs to the Stone Age. The majority of these are small daggers, formed after the pattern of the flint daggers; some already possess rivetings for fastening the blade to a handle. There are also chisels and small awls in bone handles, beads, and small ornamental leaves, and hatchets of the form of the simplest stone hatchets, with the edge hammered out and broadened. Much has proved the existence of a Copper Period corresponding to this description in the lake-dwelling in the Mond See in Austria, and in Hungary the remains of a Copper Period are particularly frequent. Parallel cases also occur in many other parts of Europe, particularly, as Virchow has proved, in the Spanish Peninsula, and in the Stone Age graves of Cujavia in Prussian Poland. These are the more important as they are most closely related to the conditions of culture discovered in the ancient strata of Hissarlik-Troy. Further unmistakable analogies occur with very ancient finds in Cyprus, and probably even with the oldest remains of Babylonian culture hitherto known. Here, too, we may include the finds of copper in the Stone Age of America. [Sidenote: The Passing of the Stone Age] So that in the normal and complete evolution of culture there seems to be first a stratum of copper as the connecting link between the Stone and Metal Ages; and this must be missing in those regions in which progress from the stone to the metal culture was only brought about at a relatively later period by external influences. This applies not only to all modern races in an age of stone, who obtained metal in recent times only through contact with European nations who had been living in the Iron Period for thousands of years, but, curiously enough, also to the greater part of Africa, where the use of iron was prevalent at a prehistoric period. Just as the modern Stone races passed straight from the Stone Age into the most highly-developed Iron Age of the most advanced culture, so also the stone stratum of Central and South Africa is immediately overlaid by a stratum of iron culture, which was brought there in ancient times, probably direct from Egypt. As there is in Egypt and throughout North Africa a regular development from the Copper-bronze Period to the complete iron culture, corresponding to the progress of the metal cultures of Europe and Asia, the point of time is thus chronologically fixed at which this important element of culture was transmitted from Europe to the blacks of Central and South Africa. [Illustration: WEAPONS USED BY MAN IN THE PERIODS OF DAWNING HISTORY Reproduced chiefly from specimens in the British Museum. ] [Sidenote: Advancing Civilisation in Bronze Age] In Western Switzerland the transition period of copper is followed without a gap in the development by the Bronze Period proper. With the introduction of bronze all the conditions of life were more highly developed in the sense of increased culture. With better tools the stations of the Bronze Age could be erected at a greater distance from the bank, often two hundred to three hundred yards; the space they take up is also much greater. The piles are not only better preserved, according as the time of their being driven in more nearly approaches our own, but they are also better worked, are often square, and the points that are rammed into the lake-bottom are better cut. The settlements of the Bronze Age often cover an area of several hundred square yards, and are no longer comparatively mean villages, as in the Stone Age; the pile settlements of the Bronze Age are well-organised market towns and even flourishing small cities, where a certain luxury already prevails. The products of their industry are graced by that beauty and elegance of form that only an advanced civilisation can create. As in the Stone Age, so also in the Bronze Age of Central and Northern Europe, the most important working-implement, which was, however, also used as a weapon, was the axe, or celt. The most primitive forms of axes, like the above-mentioned copper axes, still resemble the simple stone axes: like these, they have no special contrivance for fastening the handle. In more developed forms of axes such contrivances for fastening the handle appear first in the form of slight flanges, which become wider and wider; finally they develop into regular wings, which, by curving towards one another, develop into two almost closed lateral semi-canals on the upper side of the celt. In the hollow celts a simple socket for the handle was cast in the making; an additional means of fastening the handle was provided in a loop, which also occurs on winged celts. Besides the celt, or axe-blade, broad and narrow chisels of bronze occur in various forms for working wood. A second chief type of instrument is the one-edged bronze knife with elegantly curved back and a handle tongue. [Illustration: THE HILL OF TROY, IN WHICH IS RECORDED A WONDERFUL STORY OF MAN’S PROGRESS Seven towns of Troy were built upon this hill, one above the ruins of the other, the earliest dating from 3000 B.C.; and the brilliant excavations of Dr. Henry Schliemann, which have won him immortal fame, have contributed more to our knowledge of the history of mankind than any other excavations in our time, as on this site is concentrated a continuous record of man’s progress from the late Stone Age to the height of Greek civilisation. ] The manner in which iron was found in the lake-dwellings, as mentioned above, shows the gradual development of a period of transition between a Bronze and an Iron Age. In spite of the difference in the material which the lake-dwellers used for making their weapons and tools in the periods of transition, they still imitate the old forms received from their forefathers. Just as the first metal axes of copper are copies of the stone axes, so also, when iron first became known, were weapons made of this metal which corresponded in form to the bronze weapons that had hitherto been used. The Bronze Period was first proved to have been a complete form of culture in the North of Europe--in North Germany and Scandinavia. We have now succeeded in establishing the fact that it was a preliminary stage of the Iron Age, in locally original development, in all ancient centres of culture. It is very remarkable that the civilised states of the New World also employed only copper and bronze as working metals. Thus the Peruvians did not know iron any more than the other American peoples until they came in contact with European influences. Besides copper and bronze they had tin and lead, gold and silver. The Peruvian bronzes contain silver to the extent of five to ten per cent. There are axes or celts of bronze similar to the rudest of the first European beginnings in metal corresponding in form to the simple stone axe. Many of the other forms of weapons and implements familiar in the Bronze Age of the Old World were also made of bronze or copper in America; semi-lunar knives with a handle in the middle, lance-heads and arrow-heads, swords, war-clubs like morning stars, etc. At the same time weapons and implements of stone still remained in use. In the Old World progress beyond bronze is everywhere due to iron. [Illustration: EXCAVATIONS IN THE TEMPLE OF ATHENA AT TROY Dr. Schliemann’s discoveries in the ruins of this temple and the ruins of older buildings beneath it were among the richest in the entire annals of archæological research. ] One place has been found and most completely investigated after the method of palæontological research, with all the help afforded by archæological and historical science, where, in overlying geological strata, the evidences have been found of a progressive development of culture from the end of the Stone Age down to the brilliant days of Græco-Roman history. There the chronological connection has been obtained, not only for the metal periods, but also for the end of the Neolithic Period. This most important place is Troy, the citadel-hill of Hissarlik, by the excavation of which Henry Schliemann has won immortal fame. Schliemann’s excavations, supplemented and completed in decisive manner by Dörpfeld, have brought about the most important advancement of the history of mankind that our age can show. [Illustration: A WINE MERCHANT’S CELLAR IN ANCIENT TROY Nine colossal earthen jars were discovered by Dr. Schliemann in the depths of the Temple of Athena. They had evidently belonged to some wine merchant’s cellar in the pre-Hellenic period. ] Virchow’s name is inseparably associated with Schliemann’s. Furtwängler, in his account, based on personal observation, of the results of the excavations at Troy, has accomplished the great service of exactly determining the chronological connections of the prehistoric with the historic eras, and thereby linking the former to history. On the spot on which tradition placed Homeric Troy (says Furtwängler) there really has stood a stately citadel, which was contemporaneous with the golden age of Mycenæ, the epoch of the Agamemnon of legend, was intimately related to Mycenæan culture, and at the same time corresponds most exactly to the idea of Troy underlying the old epic. [Sidenote: Seven Towns on One Hill] The citadel-hill of Troy terminates a ridge of heights stretching westward from Mount Ida, almost parallel to the Hellespont, and slopes steeply into the Trojan plain or the valley of the Scamander. The natural hill itself is not very high, but it was overlaid by enormous layers of ruins of buildings and walls, whereby it has been considerably increased not only in height, but also in breadth. Stratum after stratum lies one upon the other like the leaves of a bud, so that the history of the habitation of this venerable place from the most ancient times can be read from these strata which have been opened up by Schliemann and Dörpfeld, as from the leaves of a book. The original ground of the hill-plateau now lies some sixty feet above the plain, but the latter may have been raised something like sixteen to twenty feet by alluvial deposits since the Trojan War. The whole stratum of ruins lying on the original ground of the hill, which Schliemann opened up, amounts to about fifty-two and a half feet. Schliemann distinguished seven or eight different layers or strata, corresponding to as many towns which were successively built on this hill, one on the ruins of the other. The lowest stratum, lying immediately on the original ground, belongs accordingly to the oldest, or first town, on the citadel-hill of Troy. Furtwängler says: [Sidenote: The First Town of Troy] By moderate computation this settlement must belong to the first half of the third millennium before Christ, but it may very well date back even to the fourth millennium. The inhabitants already used copper implements in addition to stone ones. Their whole culture is most closely connected with that which prevailed in Central Europe during the Copper Period. Clay vessels of the Copper Period from Lake Mond, in Austria, agree completely with those of the first Trojan town. Troy represents only an offshoot of Central European culture, and its inhabitants were in all probability of European origin. We have already learned that the Copper Period is the end of the Neolithic Period and the beginning of the Metal Age. In the first Trojan town there is still extraordinarily little metal used, the axes, hatchets, knives, and saws still being of stone, of the familiar Central European types, and of the same materials, among which nephrite is particularly frequent. Other materials are serpentine, diorite, porphyry, hematite, flint, etc. [Sidenote: The First Period of Troy’s Glory] The forms of these implements correspond entirely to those of the later Stone Age of Europe. The character of the ceramics also conforms in many respects, according to Virchow, to that of the European Stone Age; and the Stone Age finds at Butmir, in Bosnia, and similar ones in Transylvania seem especially to offer close analogies. It would be a highly important step toward connecting history with the Neolithic Period if the first town could be even more closely investigated, and perhaps more sharply divided from that second stratum which lies between it and the stratum described by Schliemann as the second or burnt city, and which Schliemann afterward separated into two strata, corresponding to two towns. Perhaps the metal comes only from the second or higher stratum under the burnt city. In that case the oldest would belong purely to the Stone Age. The ceramics would seem to contradict this. Furtwängler continues: High above the first town, a deep layer of débris, is the level surface of the second town, which must at least be dated back to the second half of the third millennium before Christ. It was the first period of Troy’s glory. Mighty walls protected the citadel. Three different building periods may be distinguished. The walls were brought out a long way and strengthened, and magnificent new gates were built. During the third period of this second city a prince, fond of splendour, had the old narrow gateway replaced by magnificent propylæa and a large hall-erection with a vestibule. A great conflagration destroyed his citadel. A treasure was found by Schliemann--he called it Priam’s treasure--in the upper part of the citadel wall, which was made of straw bricks. The tools of the second city are still partly of stone, but also partly of bronze, so that they already belong to the Bronze Age. [Illustration: THE EXCAVATIONS AT TROY: REVEALING THE WALL OF THE ACROPOLIS A view of the great substruction wall of the acropolis of the second city of Troy, on the west side, close to the south-west gate: (a) is the paved road, which leads from the S.W. gate down to the plain; (b) is the continuation of the great acropolis-wall of the second city on the west side of the S.W. gate; (c) is the foundation of the paved road and the quadrangular pier to strengthen it; (d) marks the masonry added by the third settlers. ] [Sidenote: The Early Culture of Troy] The general character of culture is, according to Furtwängler, still essentially Central European. And yet many an individuality has developed, and the influence of Babylonian culture is everywhere apparent, although it does not go very deep. To this influence our authority chiefly attributes the occurrence of a few pots turned on the wheel, especially flat dishes; for the potter’s wheel was still quite unknown at that time in Europe, and even at a post so far advanced toward the East as Cyprus, while in Egypt and Babylonia it had been in use from the earliest times. In this period also Troy inclines more to Central Europe as its centre of gravity, but remains far behind the peculiar development that bronze work attained there; in the metal tools no advance is made on the forms of the Copper Period. Into any close relation with Cyprus it does not come; only the basis of their culture is common to both. But this basis had a wide range, relics from German districts being often more closely related to the Trojan ones than are those from Cyprus. [Illustration: TROY: THE GREAT TOWER OF ILIUM The top of the tower is 26 ft. below the surface of the hill. The foundation is on the rock 46 ft. deep; the height of the tower is 20 ft. ] The brilliant period of the second city is followed by a long period of decline for Troy. Ruins are piled upon ruins, walls rise upon walls, but each poorer than the others; no new citadel walls, no gates, no palaces belong to this period, in which three strata--the third, fourth, and fifth towns--are distinguished. The first half of the second millennium before Christ must at least be regarded as the time of this deposit. The inhabitants evidently remained the same, and their culture is that of the second city. But no progress was made; nothing but stagnation; the same forms of vessels continue to be made, the same decorated whorls. Naturally, no active intercourse with abroad could develop in this period. And yet this was the time when an active civilised life began to develop on the islands of the Ægean Sea and on the east coast of Greece, which was to bloom in all its splendour in the following period. To this time the finds at Thera belong, where the pottery, all turned on the wheel, is already painted with a so-called varnish colour which shines like metal, and in which plants, flowers, and animals are treated in quite a new and promising naturalistic style hitherto unheard of in Europe. In Cyprus, too, the decoration of pottery developed exceedingly in wealth and variety in this period of the Bronze Age. Troy, on the other hand, is poor and degenerate. But a new period of prosperity arrived for Troy, too; this is the sixth town. Rich and powerful princes again ruled in this citadel. They enlarged it far beyond its former compass. They built strong new walls--the old ones had long since sunk in ruins--not of small stones and straw bricks as before, but of large, smooth blocks, and gates and turrets. They did not have the sloping mound of ruins levelled, as the lords of the second city had done; they let the new buildings rise in terraces, on the ruins of the old; stately mansions with wide, deep halls, covered the acropolis. Constant intercourse existed with the princes of Greece, who at that time--the second half of the second millennium before Christ--built their citadels with cyclopean walls. The Trojans employed the same peculiar, constantly-recurring small projections in their walls that we find in a Mycenæan town on Lake Copaïs in Bœotia. And, above all, the Trojans now provided themselves with those beautiful vessels painted with shining colour that characterise Mycenæan culture in Greece, and whose natural style had so wonderfully developed there on the basis of the attempts that we found at Thera. In Troy these things caused some imitation, but the results remained far behind the originals. The living, imaginative conception of the natural was closed to the Trojan; the home-made pottery kept, on the whole, to its unpainted vessels, although these were now almost entirely made on the wheel. [Illustration: THE TREASURE OF PRIAM, KING OF TROY: A COLLECTION REVEALED BY THE EXCAVATIONS This remarkable collection of regal treasure comprises the key of the treasure-house (at top of picture in centre); and, under and about the key, a number of golden diadems, fillets, earrings, and smaller jewels. On the shelf below there are a number of silver talents and vessels of silver and gold; while below them is a series of silver vases and a curious plate of copper. A variety of weapons and helmet crests of copper and bronze are displayed beneath, and on the floor are a vessel, a cauldron and a shield, all made of copper. ] Yet what chiefly interests us is the historical. The sixth town, too, was suddenly given up, destroyed, and burnt. What follows it are again only poor settlements. Its destruction must have taken place about the end of the Mycenæan epoch of culture. The seventh town, which is built immediately on the ruins of the sixth, shows, already, other and later culture. It had long been suspected that a historical kernel was concealed in the legend of Troy--now we have the monumental confirmation. There really was a Troy, which was strong and great at the same time as the rulers of Mycenæ, rich in gold and treasure, held way in Greece. And that Troy was destroyed--we may now safely affirm, from this agreement between relics and legend--by Greek princes of the Mycenæan epoch, whom the legend calls Agamemnon and his men. The seventh and eighth towns, built soon after the destruction of the sixth, show an interruption in the intercourse with Greece. There the Mycenæan period was broken by the displacement of peoples known as the Doric migration, and that rich civilised life was replaced by a relapse into the semi-barbaric conditions of the North. In Troy, too, we perceive a period of decline, “a relapse into a stage long since past; black hand-made vessels, which in their form and decoration are strikingly like the home-made pots usual in Italy, especially Etruria and Latium, in the first part of the first millennium before Christ.” Finally, the seventh town also furnishes inferior imported Greek vases with painting, though coming not from Greece itself, but from the coast of Asia Minor, where Greeks had settled in connection with the Doric migration. “The Æolic colonisation of Troas brought Ilium no fresh prosperity. Other places rose, Troy remained a miserable village. In the Hellenistic period the sky clears over Troy. What Alexander intended, Lysimachus carried out; he restores Ilium to the place of a real city with new walls, and erects a magnificent temple to Athene on the top of the acropolis.... Yet artistic creation came to no real perfection. It was only when the great men of Rome, mindful of their Trojan ancestors, began to interest themselves in the place, that new life bloomed on Troy’s ruins.” Thus the geological-archæological method relates history, merely relying upon the monuments of the soil, without requiring written evidences. Pre-history has here attained its end; it has become history. JOHANNES RANKE [Illustration: A VIEW SHOWING THE REMARKABLE CHARACTER OF THE EXCAVATIONS AT TROY Some idea of the enormous work involved in unearthing ancient Troy will be gathered from the fact, made clear in this view, that the ground-level before excavating was above the height of these buildings. A deep trench was cut, as shown in the illustration, through the whole hill of Hissarlik, the citadel town. ] THE GREAT STEPS IN MAN’S DEVELOPMENT BY PROFESSOR JOSEPH KOHLER THE MATERIAL PROGRESS OF MANKIND The opinion that our own circumstances and affairs are the only standard for judging universal history has long been obsolete. Our day, with its conceptions, beliefs, hopes, and endeavours, is but a tiny portion of the past; for thousands of years peoples have existed who have lived in other intellectual spheres than ours, who have pursued other ideals. The study of history does not consist in an examination of the past projected, as it were, into the present; it is the study of the past considered as a part of the constant coming and going of men. And in order to become qualified as historians we must first of all attain a point of view from which we may, independently of time, behold history with all its great events file by; as though we were men who had ascended to some elevation in the universe from which they could look down upon the whole earth lying as a unity before them. This is rendered possible through the power of abstraction gained from a study of history; it enables us, on the one hand, to adapt ourselves to strange times and beliefs, and, on the other, to look upon our own day--all time to its contemporary men--objectively, as a mere hour of the ages of human development. We must learn to escape from the present, to withdraw ourselves from that which we may call the tyranny of our own time. [Illustration: THE PRIMITIVE ART OF WEAVING The art of weaving arose from plaiting, and soon developed to perfection, the American Indians and most primitive peoples of our own day being skilled weavers. ] From universal history we obtain a picture of the development of humanity--that is, the development of the various active germs or principles inherent in man. By these are meant the active principles innate in mankind in the aggregate, in contradistinction to those which may exist in single individuals or in single races. The result of development is called “civilisation”--the state of intellectual being, and of outward, material life, attained by a people through evolution. Although spiritual and material culture flow into each other, they may be separated to this extent: as a physical being endowed with senses, man endeavours to obtain satisfaction of his needs, and strives for a position in relation to his environment corresponding with the efforts he has made to obtain welfare; as a feeling, inquiring, spiritual being he contains within him an ever-present desire to fuse the multitude of separate impressions he receives into unity, and to struggle forward until he arrives at a conception of the world and of life. B.C. 5000 -\| EGYPTO-BABYLONIAN \|- -\| OR \|- -\| ANCIENT ERA \|- -\| \|- Building of the Pyramids. -\| \|- Earliest monuments to kings B.C. 4500 -\| \|- in Babylonia. -\| \|- -\| \|- -\| \|- -\| \|- B.C. 4000 -\| \|- Rise of Semitic Babylonian -\| \|- kingdoms. -\| \|- -\| \|- -\| \|- B.C. 3500 -\| \|- Chaldæan Astronomy. -\| \|- -\| \|- -\| \|- -\| \|- B.C. 3000 -\| \|- -\| \|- -\| \|- -\| \|- -\| \|- B.C. 2500 -\| \|- -\| \|- -\| \|- -\| \|- Khammurabai. -\| \|- Assyrian records. B.C. 2000 -\| \|- -\| \|- -\| \|- -\| \|- -\| \|- B.C. 1500 -\| \|- Hebraic Monotheism. -\| \|- -\| \|- Zoroaster. -\| \|- Ægean Culture. -\| GRECO-ROMAN OR \|- B.C. 1000 -\| CLASSICAL ERA \|- Hellenic Culture. -\| \|- -\| \|- -\| \|- -\| \|- Thales. B.C. 500 -\| \|- Buddha. Confucius. -\| \|- Socrates. -\| \|- Plato. Aristotle. -\| \|- Stoics and Epicureans. -\| \|- A.D. 1 -\| \|- -\| \|- Christianity. -\| \|- -\| \|- Neo-platonists. -\| \|- A.D. 500 -\| \|- St. Augustine. -\| DARK \|- -\| AGES \|- Mohammed. -\| \|- -\| \|- Johannes Scotus. A.D. 1000 -\| \|- Avicenna. -\| \|- Scholasticism. -\| MEDIÆVAL OR \|- Anselm. Abelard. -\| SCHOLASTIC ERA \|- Aquinas. R. Bacon. -\| \|- Wiclif. A.D. 1500 -\| MODERN \|- Copernicus. Luther. -\| SCIENTIFIC \|- Francis Bacon. Newton. -\| ERA \|- -\| \|- Kant. Steam. A.D. 1900 -\| \|- Darwin. Electricity. OUR OWN DAY COMPARED WITH THE HISTORIC PAST Our day, with its conceptions, beliefs, hopes, and endeavours, is but a tiny portion of the past; for thousands of years peoples have existed who have lived in other intellectual spheres than ours, who have pursued other ideals. ] “Material civilisation” is the mode of life through which the obstacles opposed to humanity may be overcome. By the surmounting of obstacles is meant the conquering of enemies, particularly of hostile animals, the obtaining of means for the preservation of existence, and the employing of these means for the increase of bodily welfare. In respect of material civilisation man passes through stages that differ widely from one another, that vary according to the manner in which the necessities for existence are obtained, and according to the way in which enemies are withstood for the safeguarding of life, welfare, and acquisitions already gained. Races are spoken of as supporting themselves by the chase and fishing, or by cattle-breeding and farming, according to whether they are accustomed to derive subsistence directly from “nature unadorned,” or by means of the cultivation and utilisation of natural products. No sharp line of distinction, however, may be drawn. It is inadmissible to speak of races as supporting themselves solely by hunting and fishing, for the very same peoples feed on products of the soil wherever they are found and recognised as means of subsistence. They live, it is true, upon flesh and fish, but also upon roots and the fruit of wild trees. While in this state of civilisation, man avails himself only of that which Nature places before him; he neither adapts Nature to his desire, to his needs, or to his manner of living, nor understands how to do it. He can make no further use of Nature than to acquire a knowledge of the sources of supply, of how to seize time and opportunity, and to overcome the obstacles of life in his own territory. He ascertains the haunts of game, discovers how to obtain fish, explores for wild honey or edible roots, learns to climb the tallest trees and to let himself down into the deepest caves; but he lacks the ability to cultivate Nature, to cause her to produce according to his will. Gradually the one phase amalgamates with the other. It is not seldom that hunting tribes have small tracts of land on which they raise a few edible plants. Observation of Nature teaches them that germs develop from fallen seeds, and leads of itself to the idea that it is not best to allow plants to grow up wild, and that it would be expedient to clear the surrounding ground for their better growth. And when this stage is reached, the next step--not to allow seeds to spring up by chance, but to place them in the soil one’s self--is not very far off; and thus the mere acquisition of Nature’s raw vegetable products gives place to agriculture. Often enough we observe instances of the men of a group carrying on hunting operations, while the women are not only occupied with their domestic employments, but also till the soil; thus the men are hunters and fishers, and the women are agriculturists. Domestic work led the latter to take up the cultivation of plants, even as it led them to the other light feminine handicrafts; while the repairing of weapons and of contrivances used for the capture of animals lay within the province of the men. [Illustration: MANKIND’S PROGRESS IN HABITS OF DRESS This series of typical pictures is intended roughly to illustrate the upward progress of man from the almost nude savage to the neatly and conveniently dressed gentleman of to-day. The Elizabethan dandy is, of course, as fully dressed as man can be, and is introduced only as indicating the great change of sartorial ideas in modern times. ] The discovery of how to produce fire by artificial means, independently effected in all parts of the world--as was also the discovery of the art of navigation--was of the greatest importance for the entire future. Fire was first a result of chance. When lightning set a portion of the forest in flames, and caused a multitude of animals or fruits to be roasted, men put it to practical use. They recognised the advantage that fire gave them and sought to preserve it. The retention of the fire which had been sent down from heaven became one of the most weighty and significant of functions. Man learned how to keep wood-fibres smouldering, and how to blow them into flame at will; he also learned that it was possible to convey fire, or the potentiality of fire, along with him in his wanderings. But even then success was uncertain until a lucky chance led him to discover how to produce flames at will, by rubbing two sticks together or by twirling one against the other. These actions were originally performed for other purposes--to bore holes in a piece of wood, or to rub it into fibres; finally, one or the other was carried out with such vigour that a filament began to burn, and the discovery was made. Sparks from flint must have suggested a second method of kindling a fire; certainly the art of igniting soft filaments of wood by means of a spark--thus enabling the very smallest source of combustion to be used for human purposes--was known to man in the earliest times. The obvious results of the use of fire are means of obtaining warmth and of cooking food. [Illustration: ESQUIMAU MAKING FIRE BY FRICTION] [Illustration: AN INGENIOUS INDIAN FIRE DRILL] [Illustration: THE GAUCHO’S WAY OF GETTING A LIGHT] Self-defence had already led to the use of weapons, and, at the same time, the contrivances for hunting and fishing must have become more and more perfect. A very low degree of civilisation is that of races unacquainted with the bow and arrow, and familiar with club or boomerang only--who know how to make use merely of the weight of a substance, or, as in the case of the boomerang, of a peculiar means of imparting motion. The time previous to the discovery of the art of working in metal was the Age of Stone. It was a natural transition period during which men began to learn to make use of the malleable metals, which could be hammered and beaten into various shapes, and finally discovered how to work in iron. Iron, by being placed in the fire, brought to a white heat, and smelted, was rendered capable of being put to such uses as were impossible in the case of brittle materials--bone or stone, for example. Many races never acquired the art of working even in the softer metals, and procured metallic implements from other peoples. The great importance of metal-working is borne out by the fact that the position of the smith, even in legendary times, has been of the utmost significance. The Ages of Stone and of Metal belong to the most important stages of civilisation. Having made himself weapons, man did not employ them in fights with animals only; he also used them on his fellow-men, and at the same time arose the necessity for protective coverings--that is, the need for a means of neutralising the effect of weapons on the body. Thus followed the invention of the shield as a portable shelter, of the coat of mail and of the helmet, and of armour in general in all its different forms and varieties. Together with weapons, utensils are characteristic of material culture. Utensils are implements used in the arts of peace, domestic and industrial; they are instruments which enable us to increase power over Nature. Some utensils have undergone the same transformations as have weapons; others have their own independent history. Just as the edges of shells served as patterns for knife-blades, so did hollow stones, the shells of crustaceans or of tortoises, become models for dishes and basins. From the discovery of the imperviousness of dried earth, the potter’s art developed; it became possible to mould clay into desired shapes while moist, and then, when dry, to employ it in its new form as a vessel for holding liquids; for that which has always been of the greatest importance in the making of utensils has been the taking advantage of two opposite characteristics displayed by a material during the different stages of its manufacture--plasticity, which admits of its first being moulded into various forms, and another quality, which causes it afterward to stiffen into solidity and strength. Mansell THE MAN WITH THE HOE From the painting by Millet ] Underwood & Underwood THE WONDERFUL ADVANCE IN AGRICULTURE These pictures present a striking contrast: the sullen clod with his primitive hoe, and the great Canadian reaper drawn by thirty horses, both in use to-day. ] [Sidenote: Growth of the Textile Arts] A further acquisition was the art of braiding and plaiting, the joining together of flexible materials in such a way that they held together by force of friction alone. Thus coherent, durable fabrics may be produced, and by joining together small parts into an aggregate it is also possible to give a definite form to the whole and to adapt it to various uses. The quality of adaptability is especially developed in the products of plaiting, but the quality of imperviousness is lacking. Wickerwork was used not only in the form of baskets, but also in other shapes, as means for protection and shelter, as material for sails, as well as for tying and binding. The art of weaving arises from plaiting, and along with it come methods for spinning thread. It thus becomes possible to make an immense number of different useful articles out of shapeless vegetable material. Fibres are rendered more durable by being bound together, and textures formed from threads are adapted to the most various uses of life. This has an influence on the development of weapons also: bow-strings, slings, and lassos presuppose a rudimentary knowledge, at least, of the textile arts; and as knowledge increases, so are the products improved in turn. [Illustration: MAN’S METAL DRESS: THE DEVELOPMENT OF ARMOUR FROM ANCIENT TO MEDIÆVAL TIMES The way in which man has protected himself against his foes in battle, and the gradual progress and decline of such methods, is shown in these pictures. The first is from the monuments of Nineveh, and shows the earliest form of chain mail. In the second we see the armour of the Roman legionary, while the third shows the heavy accoutrement of a mediæval warrior. A helmet of the same period is also shown. ] Means for conveyance are also invented, that difficulties arising from distance may be overcome. At first men carry burdens upon their backs, heads, or shoulders, or in the hand, placing whatever they wish to transport in a utensil--a basket or a piece of cloth--thus producing a coherent whole; later, in order to render conveyance still more convenient, handles are invented. Objects are dragged along the ground, and from an effort to save them from injury the idea of sledges develops. Things that are round enough are rolled to their destinations; this leads to the invention of rollers and wheels, materials of required form being brought into combination with rudimentary agents of circular motion, and thus, through a rotary, a horizontal movement is obtained; and so the force of gravity is made use of, consistency of motion procured, and the hindering effect of friction overcome to the greatest possible degree. Means for carrying inanimate objects once invented, it is not long before they are put to use for the conveyance of man himself; thus methods for the transportation of human beings are discovered in the same manner as the means for the carriage of goods. [Sidenote: Man’s First Boats] In primitive times transportation by water is employed to a far greater extent than by land. Man learns how to swim in the same way as other animals do, by discovering how to repress his struggles, transforming them into definite, regular movements. The sight of objects afloat must, through unconscious analysis--experience--have taught men to make light, water-tight structures for the conveyance of goods upon water, and, later, for the use of man himself. The pole by which the first raft was pushed along developed into the rudder. Kayaks and canoes were built of wood, of bark, and of hides. In this connection, moreover, an epoch-marking invention was that of cloths in which to catch the wind--sails; and this, too, was a result of observation and experience. Man had known the effect of the wind upon fluttering cloth, to his loss, long enough before he hit upon the idea of employing it to his advantage. Finally he learned that by adjusting the sails he might make use of winds blowing from any direction. [Illustration: MAN’S METAL DRESS: THE GRADUAL MODIFICATION OF ARMOUR IN MODERN TIMES The invention of gunpowder and firearms rendered the protection of armour useless, and by the sixteenth century it had been greatly modified. The first of these pictures shows the slight armour worn by James II. The second is a suit of Japanese armour, discarded in our own time; while the last is a portrait of a present day Life-guardsman, whose cuirass is more ornamental than useful. ] [Sidenote: Man’s First Houses] Habitations are structures built in order to facilitate and assure the existence of man and the preservation of his goods. Indeed, the presence of caverns caused men to recognise the protective virtue of roof and wall, and the knowledge thus acquired gave rise in turn to the making of artificial caves. Holes beneath overhanging banks and precipices led to the building of houses with roofs extending beyond the rambling walls. Perhaps the protection afforded by leafy roofs, and the walls formed by the trunks of trees in primeval forests, may also have turned men’s thoughts to the construction of dwellings. Houses of various forms were built, circular and rectangular; some with store-rooms and hearths. The use of dwellings presupposes a certain amount of consistency in the mode of living, the presence of local ties, and a general spirit favouring fixed and permanent residence. Nomadic races use movable or temporary shelters only--waggons, tents, or huts. [Sidenote: Home and Dress] The houses of stationary peoples become more and more firm and stable. At first they are built of earth and wickerwork, later of stone, and finally of bricks, as among the Babylonians. Foundations are invented, dwellings are accurately designed as to line and angle; the curved line is introduced, bringing with it arches both round and pointed, as may be seen in the remains of Roman and Etruscan buildings. The structure is adorned, and it becomes a work of art. But man also dwelt over the water, sometimes erecting his habitations upon rafts and floats, often upon structures that rose from beneath the surface. Thus was he, dwelling in communities of various sizes, secure from the attacks of land enemies. Even to-day there are uncivilised peoples who live over water, constructing their homes upon piles. [Sidenote: Taming of the Wild] Clothing, however, was invented partly that in cold climates men might survive the winter, partly for the sake of ornament. In tropical regions man originally had no knowledge of the necessity for clothing: garments are masks, disguises; they bear with them a charm; they are the peculiar property of the medicine-men or of those who in the religious dance invoke the higher powers. Modesty is a derived feeling; it cannot exist until a high state of individualisation has been attained, until each man desires exclusive possession of his wife, and therefore wishes to shield her from the covetousness of other men. With the knowledge of dress, a desire for adornment, the effort to assist Nature in producing certain definite æsthetic effects, arises. Less uniformity in the appearance of the body is wanted, and this brings tattooing and the use of ornament into vogue. Later there is a fusing of these several aims; clothing becomes protection, veil, and ornament in one, fulfilling all three functions at the same time. Another epoch-marking discovery, often arrived at while races are still in the state of subsistence by hunting, is the domestication of animals. This may have originated in the practice of provoking one beast to attack another in order to vanquish them both the more easily. Further development, bringing with it the idea of totemism and the notion that the soul of an animal dwells in man, drew him nearer to his animal neighbours; and he sought them out as comrades and attendants. The taming of wild creatures arose from two sources--human egoism, and the innate feeling of unity and identification with Nature common to all savages; hence on the one hand, the subjugation of animals, and, on the other, their domestication. Neither employment rendered it by any means less possible for men to hold animals in reverence, or to attribute to them virtue as ancestral spirits. Such acquisitions of external culture accompany man during the transition from his subsistence by the pure products of Nature to the cultivation of natural resources, cattle-breeding and agriculture--occupations necessitating the greatest unrest and mobility. The simple life in Nature incites men to wander forth that they may discover land adapted for their support; they rove about in search of roots as well as of living prey. The breeding of domestic animals also causes them to travel in the hope of finding ground for pasture; nor does agriculture in its primitive form tend to establish permanence of residence, although it contains within itself latent possibilities of developing a settled life, one of the most important factors in the progress of mankind. [Illustration: PRIMITIVE DWELLINGS OF TO-DAY: HOUSE-BOATS AT CANTON [Sidenote: Mankind “Settling Down”] Not only are there lake-dwellers to-day, as we have seen, but even large communities, as at Canton, in China, live in boats. ] Only fixed, domestic peoples are able to create great and lasting institutions, to store up the results of civilisation for distant later races, and to establish a developed, well-organised commercial and civil life. The transition from nomadism to life in permanent residences has, therefore, been one of the greatest steps in the development of humanity. At the time of the beginnings of agriculture, however, man was still a periodic wanderer. According to the field-grass system of cultivation, seed is sown in hastily-cleared ground, which soon becomes exhausted and is then abandoned. A migration follows and new land is cleared. This system continues until men learn to cultivate part of the land in a district, allowing the remainder to lie fallow for a time in order that the soil may recover; thus they remain fixed in their chosen district. Various circumstances--for example, the danger of enemies from without, and the difficulties attending migration--must have led to this change, the transition to the system of alternation of crops. The wanderings are confined to less extensive regions, the same fields are returned to after a few years, until finally the relation of patches under cultivation to fallow land is reduced to a system, and the time of wandering is past. [Illustration: THE BEGINNINGS OF COMMERCE: PRIMITIVE PEOPLE BARTERING IVORY TUSKS AND BULL-HIDES] [Sidenote: The coming of the Craftsman] With fixed residence the forms of communities alter. The group settles in a certain district, homes are built close to one another, and the patriarchal organisation gives place to the village, which, with its definite boundaries, is thenceforth the nucleus of the social aggregate. Often several village communities have fields and forests in common, and a common ownership of dams and canals; Nature takes care that they do not become isolated, but unite together in close contact for common defence and protection. With agriculture is associated the working up of raw products. These are fashioned into materials for the support of life and for enjoyment; furniture for dwellings, clothing, tools, utensils, and weapons are made. For, however much agriculture favours a life of peace, so rarely does man live in friendship with his fellows that agricultural peoples also find it necessary to arm themselves for war. At first manufacture is not separated from farming; the agriculturist himself prepares the natural products, assisted by the members of his family. Later, it is easily seen that some individuals are more skilled than others; it is also recognised that skill may be developed by practice and that employments must be learned. Therefore it is requisite that special individuals of the community should prepare themselves for particular activities in the working up of raw products and pursue these activities in consistency with the needs of the society--trade or craft. The craftsman at first labours for the community; in every village the tailor, cobbler, smith, barber, and schoolmaster is supported by society at large. The craftsman receives his appointed income--that is, his portion of the common supply of food; and, in addition, every one for whom he expends his labour gives him something in compensation, or finds him food while employed about his house, until, finally, a systematic method of exchange is established; and with this another advance--an epoch for civilisation--is arrived at. [Sidenote: The First Labour Problem] This is the division of labour. It is found advantageous not only that the craftsman be employed as he is needed, but also that he produce a supply of products peculiar to his trade; for the times of labour do not in the least harmonise with the times of demand. Although during the first periods of industrial life men sought more or less to adjust these factors, in later times they become wholly separate from one another. There is always, in addition, labour ready to be expended on casual needs; in more advanced phases of civilisation this condition of affairs is not avoided; but wherever labour can be disassociated from fortuitous necessity, the capacity for production is greatly increased. Commodities are manufactured during the best seasons for production and are preserved until the times of need; thus men become independent of the moment. Here also, as in other problems of civilisation, it is necessary to surmount the incongruities of chance, and to render all circumstances serviceable to our purposes. [Sidenote: Crafts and Trades Developing] Exchange and division of labour are the great factors of the progress of a civilisation based upon industrialism. Crafts and trades develop and improve; greater and greater skill is demanded, and consequently the time of preparation necessary for the master craftsman becomes longer and longer. The worker limits himself to a definite sphere of production and carries his trade forward to a certain perfection. His wares will then be more eagerly sought for than those made by another hand; they are better, yet cheaper, for his labour is lightened by his greater skill. His various fellow craftsmen, and the agriculturist also, must exchange their goods for his; for the more specialised the work of an individual, the more necessary the community is to him, in order that he may satisfy all his various requirements. Exchange is at first natural; that is, commodities are traded outright, each individual giving goods directly in return for the goods he receives. The production of the community as a whole has become far richer, far more perfect. The labour of the organised society produces more than the activity of separate individuals. [Illustration: THE BEARERS OF MAN’S BURDENS: PRIMITIVE AND NATURAL METHODS OF CARRYING These illustrations show a palanquin borne by horses; the Chinese single-wheel cart and the same assisted by a donkey and a sail; pack mules and camels; and a sledge drawn by Esquimau dogs. ] [Illustration: SOME METHODS OF CONVEYANCE IN VARIOUS AGES AND COUNTRIES In this plate are illustrated a caravan of yaks; the elephant with a howdah; the African litter; reindeers as pack animals; and the familiar bullock waggon of France--a few of the many methods of carrying used by man. ] [Illustration: PRIMITIVE MONEY: SELLING A SLAVE FOR COWRIES Cowries, which are small shells, are a very primitive form of money, still used in parts of Africa and in Siam. They were formerly so used in India, where $150,000 worth used to be imported annually. In Africa 5,000 shells are equivalent to $1. ] Here, again, is shown the impulse of man to free himself from the exigencies of the moment, to lift himself above the fortuitous differences that arise between supply and demand. The more varied the production, the more difficult it becomes to find men who are able to offer the required commodity in exchange for what has been brought to them. An escape from this embarrassment lies in the discovery of a universal measure of exchange value and medium of exchange--money. Money is the means of adjustment which renders traffic between men independent of individual requirements. Mediums of exchange, particularly necessary for the carrying on of traffic between different communities, which exist in large quantities and can be divided up into parts, make their appearance in very early times. At first their values are more or less empirical, dependent upon the conditions of individual cases, until gradually a medium obtains general recognition and thus becomes money. The same need for surmounting the lack of uniformity in individual requirements has led the most different peoples in the world to the invention of money. Naturally, many different things have been employed as mediums of exchange; these vary according to geographical situations, conditions of civilisation, and the customs of races. Pastoral tribes at first employed cattle; but tobacco, cowries, strings of flat shells, bits of mother-of-pearl, rings, and hides are also used. At last it is found that metal is stable, durable, divisible, and of generally recognised value; and finally the precious metals take precedence of all others. Finally this form of money is adopted by all civilised races. Division of labour originates in the development of the handicrafts, in the distinction made between the labour of working up the raw material and that of its production. With the help of a currency it leads to a complete transformation, not only of economic relations, but also of the social conditions of men. Coin of Alexander the Great The earliest inscribed coin, 7th century B.C. Coin of Demetrius Poliorcetes, King of Macedonia Early British coin Coin of Tigranes, King of Armenia Early British coin Coin of Mithridates the Great, King of Pontus A Tetradrachm of the 5th century B.C. A Tetradrachm of the 6th century B.C. Gold coin of Philip II. of Macedon Persian Gold Daric, 5th century B.C. Early Roman bar money of the 4th century B.C. Iron bar money of South of England THE BEGINNING OF MONEY: SOME OF THE EARLIEST KNOWN COINS IN EXISTENCE Of these coins, chiefly from the British Museum, the South England iron currency bars are perhaps most interesting. Our reproduction of these is one-tenth actual size. It will be noticed that the handles and the sizes vary. ] [Illustration: THE BEGINNING OF PRINTING: STRADANUS’S PRINTING OFFICE AT ANTWERP IN THE YEAR 1600 From a very rare engraving in the British Museum ] [Illustration: THE DEVELOPMENT OF PRINTING: THE LARGEST PRESS IN THE WORLD How great has been the progress in the art of printing is seen from these two pictures. The modern Hoe printing press is a marvel of mechanism. The first editions of this History were printed on a similar machine. ] [Sidenote: Markets and Prices] Country becomes city; centres of population which rest upon an industrial basis arise; in many cases growth of the various manufacturing industries is furthered by unfavourable agricultural conditions. Such industrial centres require markets and market-places; it is necessary for the producers of raw materials to come to market from the country with their goods, in order that they may meet together with the craftsmen of the city, and with other producers from the country who offer their wares in turn. The market town is the point of departure for further culture. Here, too, the endeavour to harmonise individual incongruities exists. Fruit is sent to market; each man has his choice; an exchange value is determined by means of comparison, through analysis of the individual prices which themselves do not furnish any rational determination of worth, and therefore expose both buyer and seller to chance. Thus a market-price develops. The city is the living agency promoting industry and exchange; it brings its population into contact with the population of the country by means of the market, and prevents men from separating into isolated, unsympathetic, or even hostile groups. Here industry flourishes--arts, crafts, and large manufactures. In the latter, division of labour is developed to a maximum degree, and production in factories derives a further impulse through the introduction of machinery. Machines, in contrast to implements and utensils, are inanimate but organised instruments for labour, requiring subordinate human activity only (attendance) so that they may impart force and motion in a manner corresponding with the designs of the inventor. Machinery is originally of simple form, dependent on water or wind for motive power--rude mills, and contrivances for the guiding of water in canals or conduits belong to its primitive varieties. [Sidenote: The Use of Natural Forces] But man’s power of invention increases, and in the higher stage of industrial evolution the facilities for labour are enormous. We have but to think of steam and of electricity with all their tremendous developments of power. Finally the discovery of the unity of force leads men to look upon Nature as a storehouse of energy and to devise means by which natural forces may be guided, one form of energy converted into another and transferred from place to place; and thus man becomes almost all-powerful. He is not able to create, it is true, but he may at least mould and shape to his desire that which Nature has already formed. Thus the discovery how to direct the forces of Nature enables us again, according to the principle already cited, to escape the disabilities of human differentiation with its attendant incongruities. [Sidenote: Boundless Growth of Commerce] As already stated, division of labour leads to exchange; exchange leads to commerce. Commerce is exchange on a large scale, organised into a system with special regard to the production of a store, or supply. The latter requires a certain knowledge of trade; the centres of demand must be sought out, and the goods transported to these centres. In this way a fruitful reciprocal action develops; and as production influences trade, so may trade influence production, governing it according to the fluctuations of demand, and leading to the creation of stores of commodities for which a future market is to be expected. Thus commerce presupposes special knowledge and special skill; it develops a special technique through which it is enabled to execute its complicated tasks. Men who live by trade become distinct from craftsmen; and the mercantile class results. Merchants are men whose task is to effect an organised exchange of natural and manufactured products. Commerce always displays an impulse to extend itself beyond the borders of single nations--not to remain inland only, but to become a foreign trade also; for the products of foreign countries and climates, however valuable they may be, would be inaccessible except for commerce. Thus trade becomes both import and export. The first step is for the tradesman or his representative to travel about peddling goods, or for an owner of wares or money to offer capital to an itinerant merchant with the object that the latter may divide the profits with him later on. This leads to the sending of merchandise to a middleman, who places it on the market in a distant region--commission business. The establishment of a branch or agency in a foreign country, in order to trade there while in immediate connection with the main business house, follows; and, finally, merchants deal directly with foreign houses without the intervention of middlemen, thus entering into direct export trade. This, of course, presupposes a great familiarity with foreign affairs and confidence in their soundness; consequently it is possible only in a highly developed state of civilisation. [Illustration: “THE SHIP OF THE DESERT”: THE CARAVAN IS THE OLDEST EXISTING MEANS OF COMMUNICATION BETWEEN PEOPLES From J. F. Lewis’s picture “The Halt in the Desert,” in the South Kensington Museum (Photo, Mansell) ] [Sidenote: Birth of New Trades and Institutions] Foreign trade is carried on overland by means of caravans, and, in later times, by railways; over sea, through a merchant marine--sailing vessels and steamships. The magnitude of commerce, its peculiar methods, and its manifold, varying phases combine to produce new and surprising phenomena: traffic by sea leads to insurance and to different forms of commercial associations; intercourse by caravan gives rise to the construction of halting-stations, establishments for refreshment and repair, that finally develop into taverns and inns. And that which first arose from necessity is subsequently turned to use for other purposes: insurance is one of the most fruitful ideas of the present day; hotels are an absolute necessity. Commerce is able to bring further contrivances and institutions into being, here, again, overcoming individual incongruity by means of combination. Trade cannot always be carried on directly between the places of production and of consumption; one district requires more, another less; it would be difficult to supply all from one centre of distribution. Thus an intermediate carrying trade is developed, rendering the surmounting of obstacles less difficult and increasing the stability of the market. The demands of the middleman are compensated for by these advantages. [Sidenote: Commerce Brings the World Together] Thus the world’s commerce develops, and that which is accomplished by market traffic in lesser districts is brought about by the concentrative influence of bourses, or exchanges, in the broadest spheres. Here, as in the smaller markets, the tendency is for all prices to seek a level, to become as independent as possible of individual conditions; and so commerce between nations, and the possibility of ordering goods from the most distant lands, bring with them an adjustment: world prices are formed; and to establish these, is the business of the exchanges. The exchange is a meeting together of merchants for the transaction of business by purchase or sale. It has acquired still more the character of a world institution since men have been able to interchange advices by means of telegraph and telephone; it is possible for the bourses of different countries to transact business with one another from moment to moment, so that the ruling prices of the world can be immediately known. It has already been stated that commerce leads to a taking up of residence in foreign countries; it also leads to colonisation, and it is chiefly due to commerce that civilisation is introduced into foreign lands. [Sidenote: Supply of Human Labour] In earlier centuries the labour question was settled by means of the legal subjection of certain classes of men, until complete injustice was reached in slavery. The system was rendered still more efficient by making slave-ownership hereditary. Slavery, originated in wars and man-hunting, in times when there were but few domesticated animals and no machines, when utensils, were very imperfect and a more or less developed mode of life could only be conducted by means of the manual labour of individuals. Therefore, in order to obtain labourers, men resorted to force, introducing a slave population of which the individuals were either divided among households or kept in special slave habitations. The industry of the slave was often increased by the promise of definite privileges or private possessions. He was often granted a home and family life, and thus he became a bondman--burdened and taxed and bound to the soil, it is true, but otherwise looked upon as a man possessed of ordinary rights and privileges. Even during the days of slavery there were instances of emancipation, and the possibility was opened up of rising to the social position of a slave-owner. The evolution of a free working class, with recompense for labour, is one of the most important chapters in the history of modern civilisation. The chief sphere of development is that of the crafts and trades. The power of guilds often induces legislation in their favour; thus they become monopolies, and only such individuals as are members of an association may adopt its particular trade or craft as a profession. Sometimes the unity of a guild is broken, and the individual right to form judgments enters in place of the rules laid down by the corporation. From this results competition, which finally leads up to free competition. Through free competition, the encumbering rigidity of the guilds is avoided; it leads to a high development of the individual, and is therefore a great source of progress; it discloses the secrets of the craft, freeing men from deeply-rooted prejudices in regard to different vocations; and it increases man’s inventive capacity, producing new methods for carrying on trades and new combinations and connections. [Illustration: THE PROMISE OF PEACE: THE HAGUE CONFERENCE OF THE NATIONS OF THE WORLD IN 1907 Nothing could more effectively illustrate the ideal of international peaceful co-operation to which hopeful historians look forward than this photograph of the representatives of all the leading Powers of the world, met together at The Hague, in the year 1907, to promote the amity of nations and the eventual abolition of war. ] [Illustration: STEPS IN MAN’S DEVELOPMENT II Professor JOSEPH KOHLER] THE HIGHER PROGRESS OF MANKIND Spiritual culture may develop in the directions of knowing and of feeling. These two forms of the manifestation of consciousness are originally not to be separated from each other; but as time goes on, a preponderance of one or the other becomes noticeable. Language is the first result of spiritual culture: the communication of thoughts by means of words (sound pictures of ideas). Language arises from the necessities of life, from the need for communication among the members of a social aggregate. [Illustration: GUTENBERG, THE INVENTOR OF PRINTING Nothing has eclipsed the printing press as an agency of man’s intellectual and spiritual advancement. ] A much later acquisition, the art of writing, or the fixation of language in a definite, permanent form, stands in close connection with speech. Writing develops according to two systems: the one based on the symbolising or picturing of ideas--picture-writing, hieroglyphics; and the other on the breaking up of the speech-sounds of a language into a notation of syllables or letters--syllabic or letter writing. According to the first method thoughts are directly pictured; according to the second, sounds, not ideas, are represented by symbols--that is, the sounds which stand for the ideas are transformed into signs. The transition from sign to syllabic writing comes about in this manner: if, during its development, a language uses the same sound to express various conceptions, men represent this sound by one sign; and whenever a foreign word is reproduced in writing it is first separated into syllables, and the syllables are then pictured by the same signs as are employed to represent similar sounds--but different ideas--in the native speech. Thus symbols are employed more and more phonetically, and less and less meaning comes to be attached to them. This process must continue its development if the pronunciation changes as time goes on; the old writing, with its national symbol-method, may be retained; but with the changing of speech-sounds the new writing is altered; syllables are now represented by signs, and combinations of syllables are reproduced by means of a combination of their corresponding symbols. Thus phonetic writing was not an invention, but a gradual development. Together with the phonetic symbols, ideograms or hieroglyphs also exist, as in Babylonian. It is especially interesting, and indicative of the unity of the human mind, that the transition to syllabic writing has been arrived at independently by different races; the Aztecs, for example, exhibit a wholly independent development. [Sidenote: The Spreading of Ideas] Communication by writing may be either single or private, or general and public; in the latter case plurality is attained through such methods as the affixing of bills and placards, or by means of transcripts or reproductions of the original copy. At first the latter are made in accordance with the ordinary methods of writing; and in slave-holding communities--Rome, for example--slaves who wrote to dictation were employed as scribes. The discovery of a method by which to obtain a plurality of copies through a single mechanical process was epoch-making. The printing-press has performed a far greater service to humanity than have most inventions; for, with the possibility of producing thousands of copies of a communication, the thoughts embodied in it become forces; they may enter the minds of many individuals who are either convinced or actually guided by them. Ideas become active through their suggestion on the masses of the population. This may lead to a one-sided rule of public opinion; but a healthy race will travel intellectually in many directions, and various beliefs supplement one another, struggle together, conquer, and are conquered. In this manner thoughts awaken popular movements, rousing a people to a hitherto unknown degree, and forcing men to think and to join issues. Thus the Press becomes a factor in civilisation of the very first importance. The necessity for periodic communication, together with curiosity that refuses to wait long for information, leads to the establishment of regularly recurrent publications; and thus, in addition to the book-press, the newspaper-press, that has learned how to hold great centres of population under its control, appears. Naturally this method of aiding the progress of civilisation has its disadvantages, as have all other methods; the conception of the world becomes superficial; individuality loses in character; not only a certain levelling of education, but also a levelling of views of life and of modes of thought, results. But, on the whole, knowledge is spread abroad as it never was before. [Illustration: EXAMPLES OF AZTEC HIEROGLYPHIC SCULPTURE AND WRITING The hieroglyphics and script of the Aztecs were independently developed. The first illustration is from a sculpture in Mexico, and the other is a small reproduction of a page of the Maya manuscript at Dresden. In both cases the symbolism is only imperfectly understood at present. ] Man, as a thinking being, craves for a conception of life; and in his inmost thoughts he seeks for an explanation of the double relationship of Man to Nature and of Nature to Man, striving to bring all into harmony. This he finds in religion. Frith THE GREAT BUDDHA AT KAMAKURA, IN JAPAN Professor Kohler points out that in the history of the world’s religions, although the belief in the omnipotence of God has become so widespread, it is not thought inconsistent that a Buddha, claiming to incarnate the Supreme Being completely within himself, should appear.] [Sidenote: Man’s Craving for Religion] [Sidenote: Beginnings of Nature Worship] [Sidenote: The Realm of Shadows] Religion is belief in God; that is, belief in spiritual forces inseparable from and interwoven through the universe--forces that render all things distinct and separate, yet make all coalescent and firm, permeating all, and giving to every object its individuality. Man is impelled by Nature to conceive of the universe as divine. This idea exhibits itself universally among primitive folk in the form of animism--a belief that the entire internal and external world is animated, filled with supernatural beings that have originally no determinate nature, but which may appear in the most varied of forms, may vanish and may create themselves anew, as clouds arise from unseen vapour in the air. Spirits are supposed to be not far removed from man; families as well as individuals consider themselves to stand more or less in connection with them; and men, too, have a share in the invisible world when they have cast aside the garment of the body in dream or in death. Thus, every man is thought to have his protecting spirit, his _manitou_, that reveals itself to him through signs and dreams. Special incarnations, objects in which supernatural beings are inherent or with which they are in some way connected, are called “fetiches”; hence arises fetichism, in regard to which the strangest ideas were held in previous centuries when the science of anthropology was unknown. Trees, rocks, rivers, bits of wood, images of one’s own making--any of these are thought capable of containing beings of divine nature. Naturally, the tree or the fragment of wood or of stone is not worshipped, as men formerly thought, but the spirit that is believed to have entered it. In many cases the belief approaches worship of Nature, especially among agricultural peoples. Divinity is recognised in the shape of factors essential to agriculture--sun, sky, lightning, thunder; these being the beneficent deities, in contrast to whom are the earth-spirits who bring pestilences, earthquakes, and other evils to mankind. Thus the cult is refined; spirits are no longer attached to fetiches, but men worship the heavens, and the earth also. Religion accompanies man from birth to death. Spirits both for good and for evil are supposed to hover about him at his very birth. The soul of some being--perhaps an animal, perhaps an ancestor--enters into the new-born child, and from this spirit he receives his name. Oftentimes there is a new consecration at the time of marriage; often when an heir-apparent succeeds to the chieftainship. At his decease primitive folk believe that man enters the realm of shadows. At first he hovers over the sea or river of death, and often only after having passed through many hardships does he arrive in the new kingdom, where he either continues to live after the manner of his former existence, or, according to whether his life on earth has been good or evil, inhabits a higher or a lower supernatural sphere. To the dead are consecrated their personal possessions--horses, slaves, wives even--that they may make use of them during the new existence; men go head-hunting in order to send them new helpmates. On the other hand great care is often taken that the spirits of the departed, satisfied with their new existence, may no longer molest the world of the living: propitiative offerings are made; men avoid mentioning the name of the departed, that he may not be tempted to visit them with his presence; they seek to make themselves unrecognisable during the time immediately following his death, wear different clothes, and adopt other dwelling-places. Sometimes the light placed near the deceased for the purpose of guiding him back to his old home is moved further and further away, so that his ghost, unable to find the right path, shall never return. Thus the belief in spirits encompasses primitive man, following him step by step. [Sidenote: The Belief in Many Gods] [Sidenote: Happiness found in Religion] From animism develops worship of heroes and polytheism, with their attendant mythological narrations. The idea of the unity of the supernatural world becomes lost; and the indefinite forms of spirit become separate, independent beings, that are developed more and more in the direction of the souls either of animals or of men. This splitting up of the deity, which destroys the tendency toward unity in religion, is followed by a reaction that comes about partly through a belief in creation by a father of the gods, partly through acceptance of a historical origin of the mythological world from a single source (theogonic myths), and partly through direct banishment of the plurality of gods and a new formation of the belief in a unity according either to theistic or to pantheistic ideas. In spite of the conception of a world permeated and pervaded by God alone, the belief that certain persons and places are more powerful in respect to the divinity than others is retained; and the appearance from time to time of a Buddha who incarnates and manifests the Supreme Being directly and completely within himself--in a special manner apart from other natural phenomena--is also not looked upon as inconsistent. [Illustration: A STRANGE RELIGIOUS RITE: FUNERAL SACRIFICE OF THE TODAS IN SOUTHERN INDIA The elaborate and extraordinary funeral rites of the Todas illustrate admirably the older notions of life and death. A funeral endures for several days; the body is cremated; last of all the buffaloes of the deceased are slaughtered at the grave and thought to enter into mystic reunion with their master. In olden times a whole troop would be slaughtered, but under British influence the number has been limited to one for a common person and two for a chief. ] Religion is a thing of the emotions, not merely in the sense of having its origin in fear, or in the remembrance of lasting sensations derived from visions or dreams, but emotional in so far that it satisfies the necessity felt by men for a consistent life-conception--not an intellectual but an emotional conception. It is not the matter-of-fact desire for knowledge that finds its expression in religion, but the joy of the heart in a supreme power, the call for help of the needy, and the consciousness of our own insignificance and our mortality. Judgment is not yet abstracted from the other psychic functions; indeed, it really retires behind the emotions. [Illustration: NOAH’S SACRIFICE From the painting by Daniel Maclise, R.A. ] [Sidenote: The Basis of Worship] [Sidenote: The Growth of the Priesthood] When men thus believe in divinity, if the belief have an active influence on the emotions, it follows that the individual must establish some connection between himself and the object of his worship. This is brought about through certain actions, or through the creation of circumstances in which special conditions of consecration are perceived, and therewith the possibility of a close relationship with the Supreme Being. The acts through which this relationship may be brought about, taken collectively, are embraced in the word “worship,” and if performed according to a strict system they are called “rites.” Sacrifice has an important place among the ceremonies observed in accordance with ritual. It is based on a conception of the wants and necessities of the higher beings, and, in later times, is refined into a representation of man’s ethical feelings--unselfishness and gratitude, which give pleasure to the Deity and thus contribute to its happiness. But sacrifice does not retain its unselfish character for any great length of time. Man thinks of himself first: he makes offerings to the good spirits, but more particularly to the evil gods, in order to pacify their fury and appease their evil desires. Sacrifices are also offered to the dead, and from such offerings and memorials is developed the idea of a “family” or “clan,” which outlives the individual. Thus, emotion is the principal active agent; but intellectual power also must gradually lay its hold on the system of belief. The principles discovered are formulated into a science and the cultivation of this science becomes the special duty of the priesthood, often as a secret art--esoteric system--in which concealment is conducive to the maintenance of the exclusiveness and peculiar power of the priest class. The science becomes partly mythologic-historical, partly dogmatic, and partly ritualistic. [Sidenote: Out of Religion Came Art] The artistic instinct develops partly in connection with worship, partly in the direction of its practical application to life; and although no very sharp line of distinction is drawn between the two tendencies, the germ at least of the difference between the fine and the industrial arts is thus in existence from the very earliest times. Worship gives rise to images and pictures, at first of the very roughest form. They are not mere symbols; they are the garments or habitations with which the spirit invests itself. The spirit may take up its abode anywhere according to the different beliefs of man--in a plant, an animal, a stone, above all, in a picture or effigy that symbolically reflects its peculiarities. Therefore, the ghosts of ancestors are embodied in ancestral images. Just as skulls were reverenced in earlier times, in later days the images of the dead (_korwar_) are worshipped. Such images are the oldest examples of the art of portraiture; and the oldest dolls are the rude puppets which according to the rites of many races--the American Indians, for example--widows must wear about them as tokens, or as the husks or wrappers of their husbands’ doubles. Religion itself becomes poetry. The belief in the identity of spirits of the departed with animals, and the myths of metamorphosis, take the form of fables and fairy tales; the cosmogonic and theogonic conceptions develop into mythologies; hero sagas become epics; the myths of life in Nature become a glorification of the external world, an expression of unity with Nature, and thus a form of lyric poetry. [Sidenote: Artistic Expression of Life] Everyday life, too, demands artistic expression. At first the childish passion for the changing pictures that correspond with different ideas of the imagination joins with the desire to impress others, and finery in dress and ornamentation result. This has developed in every clime. Tattooing arises not only from a religious motive, but also from the desire for ornament. The painting of men’s bodies, the often grotesque ideas, such as artificial deformation of the head, knocking out and blackening of teeth, ear ornaments and mutilation of ears, pegs thrust through the lips, and various methods of dressing the hair, may be in part connected with religious conceptions, for here the most varied of motives co-operate to the same end. Yet, on the other hand, there is no doubt that they are also the outcome of a craving for variation in form and in colour. In the same way the dance is not only an act of worship; it is also a means of giving vent to latent animal spirits: thus, dances are often expressions of the tempestuous sensual instincts of a people. [Sidenote: The Birth of the Drama] The dance exhibits a special tendency to represent the ordinary affairs of life in a symbolic manner; thus there are war and hunting dances, and especially animal dances in which each of the participants believes himself to be permeated by the spirit of some animal which throughout the dance he endeavours to mimic. In this way dramatic representation, which is certainly based on the idea of personification, on the notion that a man for the time being may be possessed by the spirit of some other creature that speaks and acts through him, originates. Thus arose the primitive form of masques, in which men dressed themselves up to resemble various creatures, real or imaginary, as in the case of the animal masques of old time; for according to the popular idea the spirit dwells in the external, visible form, and through the imitation or adoption of its outward appearance we become identified with the spirit whose character we assume. Among many races not only masks proper were worn, but also the hides and hair or feathers of the creatures personated. Dramatic representation was furthered by the dream plays--especially popular among the American Indians--in which the events of dreams are adapted for acting and performed. Even as men seek illumination in dreams as to questions both divine and mundane, so do they anticipate through dreams the dramatic representations which shall be performed on holidays as expressions of life. [Illustration: SAVAGE DANCES: THE FAR-OFF BEGINNINGS OF THE DRAMA The dance is an effort to give symbolic expression to affairs and moods of everyday life. Thus the Zulu wedding dance is self-evident in its purpose. The second illustration depicts a strange religious dance of the Australian natives, associated with totemism or animism. The third picture shows dancers in Kandy endeavouring to banish evil spirits, and the last illustrates an Australian corroboree. From such sources the drama has been slowly evolved.] [Sidenote: Art & Play in the Life of Man] Play is a degeneration of the dance, and it arises less from the instinct for beauty than from a desire to realise whatever entertainment and excitement may be got from any incident or occurrence. From another special inclination originate those satirical songs of Northern peoples, written in alternating verses, in which the national tribunal and the voice of the people are given expression at the same time. Thus they have a truly educative character. These are the preliminary steps to the free satire and humour that gleam through the lives of civilised peoples, now like the flicker of a candle, now like a purifying lightning flash, freeing men from life’s monotony, and illuminating the night of unsolved questions. Capacity for organised play is a characteristic that lifts man above the lower animals. The expression of individuality without any particular object in view, the elevation of self above the troubles of life, and free activity, uncoerced by the necessities of existence, are characteristic both of play and of art. Thus play, as well as art, exhibits to a pre-eminent degree man’s consciousness of having escaped, if only temporarily, from the coercion of environing nature; being without definite object, it proves that he can find employment when released from the pressure of the outer world--that is, when he is momentarily freed from his endeavour to establish a balance between himself and the necessities of life, with a view to overcoming the latter. Man stands in close connection with his environment and with the immutable laws of nature; but in play and in art he develops his own personality--a development that neither in direction nor in object is influenced by the outer world and its constraint. [Sidenote: Fall of Man and Rise of the Race] The step that leads to the overcoming of custom is the recognition of right. “Right” is that which society strictly demands from every individual member. Not all that is customary is exacted by right; a multitude of the requirements of custom may be ignored without opposition from the community as a whole, although, of course, detached individuals may express their displeasure. The aggregate, however, grants immunity to all who do not choose to follow the custom. In other words, the separation of custom from right signifies the development of a sharper line of demarcation between that which is and that which ought to be. In primitive times “is” and “ought to be” are fairly consonant terms; but gradually a spirit of opposition is developed; cases arise in which custom is opposed, in which the actions of men run counter to a previous habit. Man is conscious of the possibility of raising himself above the unreasoning tendencies toward certain modes of conduct, and he takes pleasure in so doing--the good man as well as the evil. Whoever oversteps the bounds of custom, even through sheer egotism, is also a furtherer of human development; without sin the world would never have evolved a civilisation; the Fall of Man was nothing more than the first step toward the historical development of the human race. This leads to the necessity for extracting from custom such rules as must prove advantageous to mankind, and this collection of axioms--which “ought to be”--becomes law. [Sidenote: Custom, Right, and Morality] The distinction between right and custom was an important step. The relativity of custom was exposed with one stroke. Many, and by no means the worst members of communities, emancipate themselves from custom. It is the opening in the wall through which the progress of humanity may pass. Nor do the demands of right remain unalterable and unyielding. A change in custom brings with it a change in right; certain rules of conduct gradually become isolated owing to the recession of custom, and to such an extent that they lose their vitality and decay. And as new customs arise, so are new principles of right discovered. In this manner an alteration in the one is a cause of change in the other--naturally, in conformity with the degree of culture and contemporary social relations. Custom and right mutually further each other, and render it possible for men to adapt themselves to newly acquired conditions of civilisation. Together with right and custom a third factor appears--morality. This is a comparatively late acquisition. It, too, contains something of the “ought to be,” not because of the social, but by virtue of the divine authority or order based on philosophical conceptions. Morals vary, therefore, as laws vary, according to peoples and to times. The rules of morality form a second code, set above the social law, and they embody a larger aggregate of duties. The reason for this is that men recognise that the social system of rules for conduct is not the only one, that it is only relative and cannot include all the duties of human beings, and that over and beyond the laws of society ethical principles exist. Naturally conflicts arise between right and morals, and such struggles lead to further development and progress. The late appearance of ideas of morality proves that ethical considerations were originally foreign to the god-conceptions. The spirits, fetiches, and world-creators of different beliefs are at first neutral so far as morals are concerned; myths and legends are invented partly from creation theories, partly from historic data, and partly through efforts of the imagination. In primitive beliefs there is no trace of an attempt to conceive of deities as being good in the highest--or even in a lower--sense; and it would not be in accordance with scientific ethnology to appraise, or to wish to pass judgment on, religions according to the point of view of ethics. Not until the importance of morality in life is realised, and the profound value of a life of moral purity recognised, do men seek in their religious beliefs for higher beings of ethical significance, for morally perfect personalities among the gods. Underwood & Underwood THE EMBLEM OF A TRIBE: ALASKAN INDIAN TOTEM This mysterious “totem” distinguishes a family or tribe of the old Hydah Indians and is erected at Wrangel in Alaska. ] Different elements of civilisation vary greatly in their development in different civilised districts; one race may have a greater tendency toward intellectual, another toward material culture. No race has approached the Hindoos in philosophic speculation, yet they are as children in their knowledge of natural science. One people may develop commerce to the highest extent, another poetry and music, a third the freedom of the individual. The language of the American Indians is in many respects richer and more elegant than English. Therefore nothing is farther from the truth than to say that, in case one institution of civilised life is found to exist in a hunting people, another in an agricultural race, or the one in an otherwise higher, and the other in an otherwise lower nation or tribe, the institution in question must have reached a state of perfection corresponding with the general development of the people possessing it. According to this, the monogamic uncivilised races were further advanced than the polygamous Aryans of India and the Mohammedans; and the Polynesians, with their skill in the industrial arts and their dramatic dances, perhaps in a higher state of civilisation than Europeans! Development fulfils itself in communities of men. Except in a human aggregate it cannot come to pass; for the germs of development which are brought forth by the potentiated activity of the many may exist only in a society of individuals. It has therefore been a significant fact that from the very beginning men have joined together in social aggregates, partly on account of an instinctive impulse, partly because of the necessity for self-defence. Thus it came about that primitive men lived together in wandering, predatory hordes, or packs. The individuals were bound to one another very closely; there was no private life; and the sex-relationships were promiscuous. Men not only dwelt together in groups, but the groups themselves assimilated with one another, inasmuch as marriages were reciprocally entered into by them. So far as we are able to determine, one of the earliest of social institutions was that of group-marriage. Individuals did not first unite in pairs, and then join together in groups--such would soon have fallen asunder; on the contrary, group-marriage itself created the bond that held the community together; the most violent instinct of mankind not only united the few but the many, indeed, complete social aggregates. [Illustration: THE BEGINNINGS OF MONARCHY: AFRICAN CHIEF SEATED IN STATE AMONG HIS HEADMEN The tribal state has a fixed form of government. The chiefs or patriarchs of the various families stand at the head of affairs, the position of chief being either hereditary or elective. In most cases, however, it is determined by a combination of both methods, a blood descendant being chosen, provided he is able to give proof of his competence. ] Group-marriage is the form of union established by the association of two hordes, or packs, according to which the men of one group marry the women of the other; not a marriage of individual men with individual women, but a promiscuous relationship, each man of one group marrying all the women of the other group--at least in theory--and vice versâ; not a marriage of individuals, but of aggregates. Certainly with such a sex-relationship established, sooner or later regulations develop from within the community, through which the marital relationships of individuals are adjusted in a consistent manner; but the principle first followed was, as community in property, so community in marriage; and this must of itself lead to kinships entirely different from those with which we are familiar. Group-marriage was closely bound up with religious conceptions; single hordes, or packs, considered themselves the embodiment of a single spirit. And since at that time spirits were only conceived of as things that existed in nature, the horde felt itself to be a single class of natural object--some animal or plant, for example; and the union of one pack with another was analogous to the union of one animal with another. Each group believed itself to be permeated by the spirit of a certain species of animal, borrowed its name thence and the animal species itself was looked upon as the protecting spirit. The ancestral spirit was worshipped in the animal, and the putting to death or injuring of an individual of the species was a serious offence. Such a belief is called Totemism. “Totem”--a word borrowed from the language of the Massachusetts Indians--is the natural object or animal assumed as the emblem of the horde or tribe, and correspondingly the group symbolised by the class of animal or natural object is called a Totem-group. This belief led to a close union of all who were partakers of the spirit of the same animal; it also strictly determined which groups could associate with one another. And as the totem-group mimicked the animal in its dances, and fancied itself to be possessed by its spirit, it also ordered the methods of partaking of food, and all marriage, birth, and death ceremonies in accordance with this conception. It is said that, the totem being exogamous, marriages were not possible within the totem, but only without it. Precisely so; for the original conception was not that individuals formed unions, but that the whole totem entered the marriage relationship; a single marriage would have been considered an impossibility. To which totem the children belonged--to the mother’s, to the father’s, or to a third totem--was a question that offered considerable difficulty. All three possibilities presented themselves; the last mentioned, however, only in case the child belonged to another group, a sub-totem, and in that event its descendants could return to the original totem. [Sidenote: The First Ideas of Kinship] Descent in the male or in the female line occasioned in later times the rise of important distinctions between nations. If a child follow the mother’s totem, we speak of “maternal kinship”; conversely, of “paternal kinship” in case of heredity through the father. Which of these is the more primitive, or did tribes from the very first adopt either one or the other system, thus making them of equal antiquity, is a much-vexed question. There is reason to believe that maternal kinship is the more primitive form, and that races have either passed with more or less energy and rapidity to the system of descent through males, or have kept to the original institution of maternal succession. There are many peoples among whom both forms of kinship exist, and in such instances the maternal is undoubtedly the more primitive; from this it appears very probable that development has thus taken place, the more so since there are traces of maternal kinship to be found in races whose established form is paternal. [Sidenote: Growth of Marriage] As time passed, marriage of individuals developed from group-marriage or totemism. Such unions may be polygamous--one man having several wives--or polyandrous--one woman having several husbands. Both forms have been represented in mankind, and, indeed, polygamy is the general rule among all races, excepting Occidental civilised peoples. The form of marriage toward which civilisation is advancing is certainly monogamy; through it a complete individual relationship is established between man and wife; and although both individualities may have independent expression, each is reconciled to the other through the loftier association of both. Nearly associated with monogamy is the belief in union after death; it arises from the religious beliefs prevalent among many peoples. Among other races there is at least the custom of a year of mourning, sometimes for husband, sometimes for wife, often for both. Marriage of individuals has developed in different ways from group or totem marriage: sometimes it was brought about through lack of subsistence occasioned by many men dwelling together; sometimes it arose from other causes. One factor was the practice of wife-capture: whoever carried off a wife freed her, as it were, from the authority of the community, and established a separate marriage for himself. Marriage by purchase was an outcome of marriage by capture and of the paying of an indemnity to the relatives of the bride; men also learned to agree beforehand as to the equivalent to be paid. The practice of acquiring wives by purchase developed in various directions, especially in that of trading wives and in the earning of wives by years of service. Gradually the purchase became merely a feigned transaction; and a union of individuals has evolved--now sacerdotal, now civil in form--from which every trace of traffic and of exchange has disappeared. [Sidenote: Religion Ennobles Marriage] Thus already in early times marriage had become ennobled through religion. It is a widespread idea that through partaking of food in common, blood-brotherhood, or similar procedures, a mystic communion of soul may be established; and in case of marriages brought about by the mediation of a priesthood the priest invokes the divine consecration. Marriage is thereby raised above the bulk of profane actions of life; it receives a certain guarantee of permanency; indeed, in many cases, by reason of the mystic communion of souls, it is looked upon as absolutely indissoluble. [Illustration: THE IDEA OF MARRIAGE: WEDDING CUSTOMS IN MANY LANDS In countries where women are subservient to men the idea of marriage by capture or by compulsion prevails. The Bedouin bride (2) makes a pretence of escaping and is pursued by the bridegroom and his kinsmen. Some Africans (4) show their love by knocking down their prospective brides. The Moorish bride (6) shrouded and seated in bed is an object of curiosity. 1, 3, and 5 represent respectively the marriage customs of Persians, Chinese, and Moslems. ] The ownership of property also was originally communistic, and the idea of individual possession has been a gradual development. The idea of the ownership of land, especially when developed by agricultural peoples, is of a communistic nature; and, from common possession, family and individual ownership gradually comes into being. It is brought about in various ways, chiefly through the division of land among separate families: at first only temporary, held only until the time for a succeeding division arrives; later, owned in perpetuity. Nor was it a rare method of procedure to grant land to any one who desired to cultivate it--an estate that should be his so long as he remained upon it and cultivated the soil, but which reverted to the community, on his leaving it. There gradually developed a constant relationship between land and cultivator as agriculture became more extended and lasting improvements were effected on the soil. Land became the permanent property of the individual; it also became an article of commerce. Ownership of movable property even was at first of communistic character. Clothing and weapons, enchantments effectual for the individual alone, such as medicine-bags or amulets, were, to be sure, assigned to individuals in very early times; but all property obtained by labour, the products of the chase or of fishing, originally belonged to the community, until in later days each family was allowed to claim the fruits of its own toil, and was only pledged to share with the others under certain conditions. Finally, individuals were permitted to retain or to barter property which they had produced by labour; and exchange, especially exchange between individuals, attained special significance through the division of labour. The individualisation of the ownership of movable property was especially furthered by members of families performing other labour, outside the family, in addition to their work within the family circle. Although the fruit of all labour accomplished within the family was shared by the members in common, the results of work done outside became the property of the particular individual who had performed the labour. Consequent expansion of the conception of labour led men to one of the greatest triumphs of justice, to the idea of establishing individual rights in ideas and in combinations of ideas, to the recognition of intellectual or immaterial property--right of author or inventor--one of the chief incentives to modern civilisation. [Illustration: THE CHURCH AND MARRIAGE: A WEDDING SCENE In very early times marriage had assumed a religious significance and came to be regarded among the sacred as opposed to the secular functions of life. ] On the other hand, individual rights in transactions led to conceptions concerning obligations and debts. Exchange, either direct or on terms of credit, brought with it duties and liabilities for which originally the persons and lives of the individuals concerned were held in pledge, until custody of the body--which also included possession of the corpse of a debtor--was succeeded by public imprisonment for debt, and finally by the mere pledging of property, imprisonment for debt having been abolished--a course of development through which the most varied of races have passed. [Sidenote: Rights of Property] The relation of the individual to his possessions led men at first to place movable property in graves, in order that it might be of service to the departed owner during the life beyond; hence the universal custom of burning on funeral pyres, not only weapons and utensils, but animals, slaves, and even wives. In later times men were satisfied with symbolic immolations, or possessions were released from the ban of death and put into further use. The property of the deceased reverted to his family, and thus the right of inheritance arose. There was no right of inheritance during the days of communism; on the death of a member of the family a mere general consolidation of property resulted; with individual property arose the reversion of possessions to the family from which they had been temporarily separated. Thus property either reverted to the family taken as a whole, or to single heirs, certain members of the family; hence a great variety of procedure arose. Up to the present day inheritance by all the children, or inheritance by one alone, exists in Eastern Asia as in Western nations. In like manner criminal responsibility was originally collective; the family or clan was held responsible for the actions of all its individual members except those who were renounced and made outcasts. Such methods of collective surety still exist among many exceedingly developed peoples; but the system is gradually dying away, the tendency being for the entire responsibility to rest upon the individual alone. [Sidenote: Beginning of the Community] The state is a development of tribal, or patriarchal, society. The tribal group is a community of intermarried families, all claiming descent from a common ancestor. From tribal organisation the principle is developed that participation in the community is open only to such individuals as belong to one or other of the families of which it is composed; and the political body thus made up of individuals related either by blood or through marriage is called a patriarchal, or tribal, state. This form of community was enlarged even in very early times, advantage being taken of the possibility of adopting strangers into the circle of related families, and of amalgamating with them. Still, the fundamental idea that the community is composed of related families always remains uppermost in the minds of uncivilised peoples. The tribal state gradually develops into the territorial state. The connection of the community with a definite region becomes closer; strange tribes settle in the same district; they are permitted to remain provided tribute is paid and services are performed, and are gradually absorbed into the community, the strangers and the original inhabitants--plebeians and patricians--united together into one aggregate. Thus arises the conception of a state which any man may join without his being a member of any one of the original clans or families. [Sidenote: Growth of the Idea of a State] In this way the idea of a state becomes distinct from that of a people bound together by kinship, the latter being especially distinguished by a certain unity of external appearance, custom, character, and manner of thought. This is not intended to suggest that an amalgamation of different race elements in a state and an assimilation of different modes of thought and of feeling are not desirable, or that a spirit analogous to the sense of unity in members of the same family is not to be sought for; such a condition is most likely to be attained if a certain tribe or clan take precedence of the others, as the most progressive, to which the various elements of the people annex themselves. [Illustration: “IN THE NAME OF JUSTICE”: SOME OLD METHODS OF TORTURE These pictures represent: 1. Roman gaolers cutting off a Christian’s ears. 2. The cangue as still used in China. 3. A prisoner on the rack in Mediæval England. 4. Torture of the Iron Chair. 5. The ordeal of fire and branding. ] [Sidenote: Tribes and their Chiefs] The tribal state has a fixed form of government. The chiefs or patriarchs of the various families stand at the head of affairs, the position of chief being either hereditary or elective. In most cases, however, it is determined by a combination of both methods, a blood descendant being chosen provided he is able to give proof of his competence. In addition there is often the popular assembly. In later times many innovations are introduced. Passion for power united to a strong personality often leads to a chieftainship in which all rights and privileges are absorbed or united in the person of one individual; so that he appears as the possessor of all prerogatives and titles, those of other men being entirely secondary, and all being more or less dependent upon his will. Religious conceptions, especially, have had great influence in this connection. Nowhere is this so clearly shown as in “teknonymy,” an institution formerly prevalent in the South Pacific islands, according to which the soul of the father is supposed to enter the body of his eldest son at the birth of the latter, and that therefore, immediately from his birth, the son becomes master, the father continuing the management of affairs merely as his proxy. Other peoples have avoided such consequences as these by supposing the child to be possessed by the soul of his grandfather, therefore naming first-born males after their grandfathers instead of after their fathers. Another outcome of the institution of chieftainship is the chaotic order of affairs which rules among many peoples on the death of the chieftain, continuing until a successor is seated on the throne--a lawless interval of anarchy followed by a regency. The power of a chieftain is, however, usually limited by class rights; that is, by the rights of sub-chieftains of especially distinguished families, and of the popular assembly, among which elements the division of power and of jurisdiction is exceedingly varied. These primitive institutions are rude prototypes of future varieties of coercive government, of kingship, either of aristocratic or of republican form, in which the primitive idea of chieftainship as the absorption of all private privileges is given up, and in its place the various principles of rights and duties of government enter. [Sidenote: Growth of Military Classes] Class-differentiation with attendant privileges and prerogatives is especially developed in warlike races, and in nations which must be ever prepared to resist the attacks of enemies, by the establishment of a militant class. The militant class occupies an intermediate position between the governing, priest, and scholar classes on the one hand, and the industrial class--agriculturists, craftsmen, merchants--on the other. Employment in warfare, necessary discipline, near association with the chieftain, and the holding of fiefs for material support give to this class a unique position. Thus the warrior castes developed in India, the feudal and military nobility in Japan, the nobility in Germany, with obligations and service to feudal superiors and to the Court. This system survives for many years, until at last feudal tenure gradually disappears, and its attendant prerogatives are swallowed up by all classes through a universal subjection to military service; although even yet a distinct class of professional soldiers remains at the head of military affairs and operations, and will continue to do so as long as there is a possibility of internal or external warfare. However, here too the militant class is absorbed into a general body of officials. Officials are citizens who not only occupy the usual position of members of the state, but to whom in addition is appointed the execution of the life functions of the nation, as its organs; in other words, such functions as are peculiar to the civic organisation in contradistinction to the general functions exercised and actions performed by individual citizens as independent units. Officialism includes to a special degree duty to its calling and to the public trust, and there are also special privileges granted to officials within the sphere appointed for them. [Sidenote: The Birth of Parliaments] In a society governed by a chieftain, as well as in a monarchy, there is a popular assembly or consultative body; either an unorganised meeting of individuals, or an organised convention of estates founded on class right. A modern development, that certainly had its prototype in the patriarchal state, is the representative assembly, an assembly of individuals chosen to represent the people in place of the popular gathering. The English Government, with its representative legislative bodies, is a typical example in modern civilisation. One of the chief problems encountered not only in a society ruled by a chieftain, but also in states of later development, whether governed by a potentate or by an aristocracy, is the relation of temporal to spiritual power. Sometimes both are united in the head of the state, as in the cases of the Incas of Peru and of the Caliphate. Sometimes the spiritual head is distinct and separate from the temporal; frequently the two forces are nearly associated, a member of the imperial family being chosen for the office of high-priest, as among the Aztecs. Often, however, the two functions are completely independent of each other, as among many African races, the medicine-man occupying a position entirely independent of the chieftain. Such separation may, of course, lead to friction and civil war; it may also become an element furthering to civilisation, a source of new ideas, opening the way to alliances between nations, and setting bounds to the tyranny of individuals, as exemplified in the relation of the Papacy to the Holy Roman Empire. [Sidenote: State Justice a Momentous Step Forward] The form of state in which the functions of government are exercised by a chieftain contributes greatly to state control and enforcement of justice. The realisation of right had been from the first a social function; but its enforcement was incumbent on the unit group of individuals (families or tribes bound together by friendship). The acquisition by the state of the power to dispense justice and to make and enforce law is one of the greatest events of the world’s history. The idea of all right being incorporated in the chieftain (and social classes) played an important part in bringing about this condition of affairs; for as soon as this conception receives general acceptance, the chieftain, and with him the state, become interested in the preservation and enforcement of justice, even in its lower forms in the common rights of the subjects. On the other hand, not only the interests of chieftainship, but also those of agriculture and commerce, are furthered by the preservation of internal peace; and internal peace calls for state control of justice and enforcement of law. Mansell AN EARLY EGYPTIAN REPRESENTATION OF JUSTICE “The Judgment of the Dead” as illustrated by innumerable paintings on the walls of Egyptian temples and tombs. ] Moreover the religious element worked to the same end. Wickedness was held to be an injury to the deity, whose anger would be visited upon the entire land--a conception that lasted far into the Middle Ages, and according to which the fate of Sodom and Gomorrah was held to be typical of the effect of the curse of God. Already in primitive times religion led to a strange idea of justice--secret societies consecrated by the deity took upon themselves the function of enforcing right, instituting reigns of terror in their districts, maintaining order in society, and claiming authorisation from the god with whose spirit they were permeated. Later, influenced by all these causes, the social aggregate took over the control of justice. It was already considered to be the upholder of right, the servant of the deity, the maintainer of public peace, the dispenser of atoning sacrifices, etc.; and so the various elements conceived of as justice, which had previously been distributed among the single families, tribes, associations, and societies, were combined, and placed under state control. [Illustration: AN EARLY CONCEPTION OF THE SPIRIT OF JUSTICE: THE JUDGMENT OF SOLOMON Reproduced from the picture by the French artist, Nicolas Poussin, who flourished in the first half of the seventeenth century. ] [Illustration: THE MODERN IDEAL OF JUSTICE From the fresco by Gerald Moira in the New Central Criminal Court, London. Most of the figures are studies from well-known public men of recent years. ] [Sidenote: Terror & Tyranny of Religion] [Sidenote: The Ordeal and the Curse] Certain forms for the dispensation of justice, judging of crimes, and determining of punishments were developed. Thus arose the different forms of judicial procedure, which, for a long time bore a religious character. The deity was called upon to decide as to right and wrong--divinity in the form of natural forces. Hence the judgments of God through trial by water, fire, poison, serpents, scales, or--especially in Germany during the Middle Ages--combat, or decision by the divining eye, that was closely allied to the so-called trial by hazard. A peculiar variety of ordeal is that of the bier, according to which the body of a murdered man is called into requisition, the soul of the victim assisting in the discovery of the murderer. Ordeals are undergone sometimes by one individual, sometimes by two. An advance in progress is the curse, which takes the place of the ordeal, the curse of God being called down upon an individual and his family in case of wrongdoing or of perjury. The curse may be uttered by an individual in co-operation with the members of families. Thus arise ordeals by invocation and by oath with compurgators. Originally a certain period of time was allowed to pass--a month, for example--for the fulfilment of the curse. In later times, whoever took the oath--oath of innocence--was held guiltless. Witnesses succeeded to conjurers; divining looks were replaced by circumstantial evidence; and, instead of a mystic, a rational method of obtaining testimony was adopted. The development was not attained without certain attendant abuses; and the abolition of ordeal by God was among many peoples--notably the inhabitants of Eastern Asia, the American Indians, and the Germans of the Middle Ages--succeeded by the introduction of torture. In many lands torture stood in close connection with the judgment of God; in others it originated either directly or indirectly in slavery. According to the method of obtaining evidence by torture, the accused was forced through physical pain to disclosures concerning himself and his companions, and, in case he himself were considered guilty, to a confession. However barbarous and irrational, this system was employed in Latin and Germanic nations excepting England, until the eighteenth century, in some instances even until the nineteenth. [Sidenote: The Slow Building up of Law] [Sidenote: Evolution of the Modern State] Judgment was first pronounced in the name of God; in later times, in the name of the people or of the ruler who appeared as the representative of God. The principles of justice, the validity of which at first depends upon custom, are in later times proclaimed and fixed as commands of God. Thus systems of fixed right come into being first in the form of sacred justice, then as commands of God, and finally as law. Law is a conception of justice expressed in certain rules and principles. Originally there were no laws; the standard for justice was furnished to each individual by his own feelings; only isolated cases were recorded. As time advanced, and great men who strove to bring about an improvement in justice arose above the generality of mankind; when the ruling class became differentiated from the other classes; when it was found necessary to root out certain popular customs--then, in addition to the original collection of precedents, there arose law of a higher form: law that stood above precedent, that altered custom, and opened up new roads to justice. Great codes of law have not been compilations only; they have led justice into new paths. Originally a law was looked upon as an inviolable command of God, as unalterable and eternal; its interpretation alone was earthly and transitory. As years passed, men learned to recognise that laws themselves were transitory; and it became a principle that later enactments could alter earlier rules. The relations of later statutes to already established law, and how the laws of different nations influence one another, are difficult, much-vexed questions for the solution of which special sciences have developed--transitory and international law. Judgment and law are intimately concerned with justice, the conception of right as evolved from the double action of life and custom. To this development of justice is united an endeavour of the state or government not only to further welfare by means of the creation and administration of law, but also to take under its control civilising institutions of all sorts. This was originally a feature of justice itself; certain practices inimical to civilisation were interdicted and made punishable offences. Already in the Middle Ages systems of police played a great part among governmental institutions, especially in the smaller states. Subsequently the idea was developed that not only protection through the punishment of crime, but also superintendence of and promotion of the public weal, should be administered by law; and thus the modern state developed with its policy of national welfare. With this arose the necessity for a sharper distinction to be drawn between justice and the various actions of an administration; and thus in modern times men have come to the system--based on Montesquieu--of the separation of powers and independence of justice. Justice varies according to the development of civilisation, and according to the function that it must perform in this development; in like manner every age creates its own material and spiritual culture. Every poet is a poet of his own time. [Sidenote: Right Way to View History] The notion of natural right, however unhistorical it was in itself, characterised a period of transition in so far as it enabled men to form a historical conception--a conception of what might be: for, by contrasting actual with ideal justice, we are enabled to escape the bonds of the opinions of a particular time, and to look upon such opinions and views objectively and independently. Yet it is certainly a foolish proceeding to consider an ideal, deduced principally from conceptions and opinions of the present, to be a standard by which to measure the value of historical events of all times, sitting in judgment over the great names of the past with the air of an inspector of morals. The office of the historian as judge of the dead is quite differently constituted. Every age must be judged in accordance with the relation which it bears to the totality of development; and every historical personage is to be looked upon as a bearer of the spirit of his day, as a servant of the ideas of his time. Thus it is quite as wrong to pronounce moral censure on the men of history, as it is wrong to judge an era merely according to its good or evil characteristics. A period must be estimated according to what it has either directly or indirectly accomplished for mankind. [Sidenote: Conception of a United World] There are common factors of civilisation shared by nations themselves, through which many contradictions disappear. The religious civilisations of Christianity, Mohammedanism, Judaism, Buddhism and Confucianism have been the determining factors of the intellectual and emotional life, even influencing the course of events, in vast regions. And thus it is also comprehensible that in the judicial life of nations there is an endeavour for a closer approach, and also the existence of equalising tendencies. In spite of countless variations in detail, there is a certain unity of law in the entire Mohammedan world; and although the hope of establishing the unity of Roman canonistic law over the whole of Christendom has not been realised none the less it was a tremendous idea: that of a universal empire founded on the Roman law of the imperators, and placed under the rule of the German emperor, thus ensuring the continuance of the law of the Roman people--an idea that swayed the intellects of the Middle Ages up to the fourteenth, even to the fifteenth century, and according to which the emperor would have been the head of all Europe, the other sovereigns merely his vassals or fief-holders. This idea, once advocated by such a great spirit as that of Dante, has, like many others, passed into oblivion; and in its place has arisen the conception of independent laws of nations. Yet the original idea has had great influence: it has led to a close union of Christian peoples; it opened a way for Roman law to become universal law, although, to be sure, English law, completely independent of that of Rome, has grown to unparalleled proportions as a universal system, entirely by reason of the marvellous success of the English people as colonists. Likewise international commerce will of itself lead to a unification of mercantile, admiralty, copyright, and patent law. Then the idea of an international league must develop, arising from the idea of the unity of Christian nations. We have advanced a great distance beyond the time when every foreigner was considered an enemy, and when all foreign phenomena were looked upon as strange or with antipathy. Rules for international commerce are developed; state alliances are entered into for the furtherance of common interests and for the preservation of peace. Many tasks which in former times would have been executed by the empire are now undertaken by international associations; and the time for the establishment of international courts of arbitration for the adjustment of differences between states is already approaching. [Sidenote: Common Interests of Mankind] It also seems probable that states will unite to form political organisations, wholly or partially renouncing their separate positions. Thus nations will be replaced by a federal state, and a multitude of unifying ideas which would otherwise be accomplished with difficulty will come to easy realisation. Federal states were already in existence during the times of patriarchal communities: an especially striking example is that of the admirably constituted federation of the Iroquois nations. [Sidenote: Universal Transmission of Culture] The vision of no man may pierce through to the ultimate end of the processes of history, and to advance hypotheses is a vain endeavour--quite as vain as it would be to expect Plato to have foretold the life of modern civilisation or the imperial idea of mediæval times, or Dante to have foreseen modern industrialism or the character of industrial peoples. To-day we are more certain than ever that no process of development, however simple it may have been, has ever taken place according to a fixed model; all developments have had their own individualities according to place and to time. Thus we must forego discussion of the future. However, there is another point of view. Development of nations as well as of individuals leads either to progress or to decay. No people may hope to live eternally; and how many acquisitions already gained will be lost in the future it is impossible to say. If a nation declines, it either becomes extinct or is annihilated by another state; it becomes identified with the newer nation, and disappears with its own character; thus its civilisation may also disappear. This is a serious possibility. It is the Medusa head of the world’s history which we must face--and without stiffening to stone. [Sidenote: Influence of Peoples on One Another] There is one truth, however, the knowledge of which fills us with hope for the future: it is the fact that the results of development and civilisation are often transfused from one people to another, so that a given development need not start again from the very beginning. This is owing to the capacity which races have for absorbing or borrowing civilisations. Absorption of culture is by no means universal; it does not prevent the occasional disappearance of civilisation, for every civilisation has before it at least the possibility of death. Nevertheless the transmission and assimilation of culture is constantly taking place. There are various ways in which it may be brought about. A conquering nation may bring its own civilisation with it to the conquered; culture is often forced upon the latter by coercive measures. The conquerors may acquire culture from the vanquished; or assimilation of culture may come about without the subjection of a people, through the unconscious adoption of external customs and internal modes of thought. Finally, culture may be borrowed consciously from one nation by another, the one state becoming convinced of the outward advantages and inner significance of the foreign civilisation. In this way the problem of development becomes very complicated; many institutions of vanished races thus continue to live on. Certainly the race that acquires a foreign civilisation must, among other things, be so constituted in its motives and aspirations as to lose the very nerves of its being, its very stability, in order that, intoxicated with the joy of a new life, all traces of its past existence may be allowed to break up and disappear. On the other hand, many a promising germ of culture possessed by a vigorous people may come to grief, owing to the influence of acquisitions from without. But, in return, a race that knows how to assimilate foreign culture may obtain a civilisation of such efficiency as it would never before have been capable of attaining, by reason of the fact that its power is established on a recently acquired basis, and because it has been spared a multitude of faltering experiments. [Sidenote: Progress Goes on For Ever] Civilisation may be mutually obtained from reciprocal action, nations both giving and taking. Such a relation naturally arises when states enter into intercourse with one another, when they have become acquainted with one another’s various institutions and are able to recognise the great merits of foreign organisations and the defects of their own. Especially the world’s commerce, in which every nation wishes to remain a competitor, compels towards mutual acceptance of custom and law; no nation desires to be left behind; and each discovers that it will fall to the rear unless it borrow certain things from the others. Such reciprocal action will be the more effective the more like nations are to one another, the better they understand each other, and the more often they succeed not only in adopting the outward forms, but in absorbing the principles of foreign institutions into their own beings. Thus we may hope that even if the nations of to-day decay and disappear, the labour of the world’s progress will not be lost; it will constantly reappear in new communities which may rejoice in that for which we have striven, and which we have acquired by the exertion of our own powers. JOSEPH KOHLER THE SEVEN WONDERS OF ANCIENT CIVILISATION From the French of Victor Hugo By HAROLD BEGBIE =The Temple of Diana at Ephesus speaks:= The sun standeth in the high places of the mountains, Full of brightness and mirth is the dawn. But my loveliness is not shamed by him, Neither is it dimmed; For, behold and consider well, the sun is not more than thought. That which yesterday I was, to-morrow I shall be: I live: I wear upon my brow the moving ages and the spirit of man, And genius, and art: These things are more wonderful than the sun. Senseless is the stone in the earth, And the granite is not more than the formless night; The alabaster knoweth not the dayspring, Porphyry is blind, And marble is without understanding; But let Ctesiphon pass, Or Dædalus, or Chresiphon, And fix his eyes, full of the divine flash, Upon the ground where the rocks slumber, And lo, they awake, they tremble, they are stricken with understanding; The granite, lifting some vague and troubled eyelid, Struggleth to behold his master: The rock feeleth within himself the breathing of the unhewn statue, The marble stirs in the midnight of his darkness, Because that he is aware of the soul of a man. The buried alabaster desireth to rise up from the grave, Earth shudders, it trembleth violently, It feels upon it the will of a man; And behold, beneath the gaze of him who passeth with creation in his eyes, From the deeps of the sacred earth The sublime palace comes forth and mounts upward. =When she has made an end, the Gardens of Babylon sing their laud of Semiramis:= Glory to Semiramis, Who reared us up on the arches of the great bridges Whose span outraceth time. This great queen was wont to delight herself beneath our floating branches; In the midst of the ruin of two empires She laughed in our groves, She was happy in our green places; She conquered the kings of far countries, And when the man had humbled himself before her, Lo, she would go upon her way, She would come hither, She would sigh gleefully under our branches, Very pleasantly would she lie down on the skins of panthers. =And after the Gardens have sung, there is heard the voice of the Mausoleum of Halicarnassus:= I am the monument of a heart that knew itself infinite; Death is not death beneath my dome of blue, Beneath my dome, death is victory, Death is life. Here hath death so much of gold and of precious stone That he boasteth himself thereof; Behold, I am the burial which is a pageant, And the sepulchre which is a palace. =Then, like a great thunder, the voice of Jupiter:= I am the Olympian, The lord of the muses; All that which hath life, or breath, or love, or thought, or growth. Groweth, thinketh, liveth, loveth, and breatheth in me. The incense of supplication which rises to my feet Trembles with terror and affright; The slope of my brow doth touch the axis of the world; The tempest speaketh with me before he troubles the waters; I endure without age; I exist without pang; Unto me one thing only is impossible-- To die. =After Jupiter, from the island of Pharos sounds the voice of the great Lighthouse:= In the midst of the mighty waters I tarry for the ceasing of the centuries. Sostratus the Cnidian built me, He built me that there might be thrown Across the rolling waters, And through the darkness where lurketh destruction, A rebuke to the lovely vanity of the stars. =After the Lighthouse, the Colossus at Rhodes:= I am the true Lighthouse. Rhodes lies at my threshold. Before the steadfast gaze of my unsleeping eyes Winter maketh white the mountains. I behold the deep waters in their cavernous mists; I am the sentinel whom none cometh to relieve; I look forth upon the coming of the night, And upon the coming of the dawn I behold the lifting of the mists, I behold the terror of the sea, With the immense dreaming of Colossus. =And last speaks the Pyramid of Cheops:= The desert, spread like a table, lieth beneath my foundations. Lo, from some mysterious gateway of the night I lift unto heaven my stair of terror, And out of the darkness itself seemeth it that I am builded. The sphinxes dropped their broods in the caverns; The centuries went by; the winds passed sighing; And Cheops said again: I am eternal! =Then, after a profound silence, the creeping worm of the sepulchre lifteth up his voice:= I say unto you Buildings that ye rise, and arise still more! Set ye up a stone above a stone, Above cities lift yourselves up, O temples! Lift up yourselves, like Babel! Column above column; Higher and yet higher; Let palaces arise upon the hollow places And let nothingness be fastened upon the foundations of night! Ye are like smoke, Therefore exalt yourselves with the clouds! Set not an end to your boasting! Mount up, mount up, for ever! Lo, in the dust beneath your feet I crawl and wait. Small am I, O mighty ones, And yet I say unto you, From the going down of the sun to his rising up, From all the corners of the earth, Everything which hath substance and which hath being, The thing which is sorrowful, And the thing which is glad, Descend unto me. And I only have strength, and I only endure for ever, For behold, I am death. [Illustration: THE HANGING GARDENS OF BABYLON The Hanging Gardens have been attributed to Semiramis, although Nebuchadnezzar is also said to have built them to please one of his wives, who, coming from a hilly country to Babylon, in the midst of a vast and barren plain, sighed for some reminder of the leafy beauty of her old home. The gardens, built in the form of a square extending some 700 feet on each side, rose to a great height in terrace upon terrace supported by massive pillars. A remarkable hydraulic system kept their multitudinous plants and trees in almost perpetual verdure. ] [Illustration: THE PYRAMIDS OF EGYPT For six thousand years the Pyramids have thrown their shadow across the sands of Egypt. The stone of which they are built would make a great wall from Cairo to New York; the white marble which covered them would have built more king’s palaces than Egypt has had need of. The building of the Great Pyramid employed 100,000 slaves for 30 years, and the geometrical perfection of it is a marvel to this day. Khufu, or Cheops, who built the Great Pyramid--probably as his tomb--reigned about 4700 B.C., so that the pyramid is more than three times as old as the Roman Empire. ] [Illustration: THE MAUSOLEUM AT HALICARNASSUS This famous monument of antiquity was erected in the year 354 B.C. to the memory of King Mausolus of Caria by his widow Artemisia, at Halicarnassus, the beautiful Greek city-colony on the shores of the Ægean Sea. Some idea of its size will be gathered from the fact that it was surrounded by an esplanade which measured over three hundred feet on each side, while its total height was nearly a hundred and fifty feet. The statue existed almost intact until the fourth century of our own era, and was finally destroyed in the Middle Ages by the Turks. ] [Illustration: THE COLOSSUS OF RHODES This short-lived achievement of ancient art dated from about 300 B.C. It was the largest of a hundred statues to the sun-god raised in the island of Rhodes, any one of which, said Pliny, would have made famous the place where it stood. Dedicated to Apollo, who was thought to have delivered Rhodes from Demetrius Poliorcetes, it was made from the engines of war which that besieger left behind. One finger of it was larger than an ordinary statue. An earthquake in 224 B.C. destroyed it, but even in its broken and fallen state it was long the wonder of Rhodes. ] [Illustration: THE TEMPLE OF DIANA AT EPHESUS “Great is Diana of the Ephesians.” Her temple was burned down in 356 B.C., and subsequent to that year the great temple famed in history was erected by the Ionians. It is said to have taken 220 years to construct, and measured about 400 feet in length and 200 feet in width, while it contained no fewer than 127 Ionic columns nearly 65 feet high. The temple was despoiled by Nero and destroyed by the Goths in 262 A.D., but some of its ruins still remain. ] [Illustration: THE STATUE OF JUPITER ON OLYMPUS The world-famous statue of Jupiter was the work of the great sculptor Phidias. It measured 43 feet in height above the base. The body of the god was carved from ivory, and the drapery was of solid gold. No other statue of such magnitude, of such artistic perfection, or of such precious material, has been known to history. Among the ruins of the temple are still to be seen the remains of the black marble mosaic on which the statue stood. ] [Illustration: THE LIGHTHOUSE OF ALEXANDRIA On the island of Pharos, close to Alexandria, stood the famous lighthouse erected by Ptolemy Philadelphus about 280 B.C. Constructed of white marble, in a series of vast stages of vaulted masonry, it reached the height of 520 feet, and in its summit burned night and day, an immense beacon fire of wood, which could be seen 30 miles at sea. The lighthouse was gradually destroyed by earthquakes and the action of the sea, but existed in some condition to the end of the 13th century. ] [Illustration: BIRTH OF CIVILISATION AND THE GROWTH OF RACES] THE RISE OF CIVILISATION IN EGYPT BY PROFESSOR FLINDERS PETRIE In looking back to the beginning of civilisation in any country, we have to deal with the physical changes which the land has undergone, and to consider the conditions which promoted or hindered the advance of its inhabitants. The nature of a country largely rules the nature of its people, both bodily and mentally; and it may even be true that, if sufficient time be given, the same character and structure will always be produced by equal conditions. [Sidenote: Civilisation 10,000 Years ago] [Sidenote: How we can Fix the Date] From historical records, and the cemeteries that have been examined, it appears that the beginning of a continuous civilisation in Egypt must be set as far back as about 10,000 years ago, or 8000 B.C. The question then is how far the condition of the country at that age was similar to that now seen? The present state is quite new, geographically speaking, as the deposit of mud by the Nile, providing a suitable soil, is only a matter of a few thousand years. The accumulation of deposit is about 5 in. in a century (4·7 at Naukratis, 5·1 at Abusir, 5·5 at Cairo); and the depth of it is not less than 26 ft., and varies in different places down to 62 ft. The lower depths are, however, often mixed with sand beds, and do not show the continuous mud deposit; hence the average depth of 39 ft. is too large, and if we accept 35 ft., it will certainly be a full estimate. At the average rate of deposit, this would be formed in 6,000 years. But, on the other hand, the deposit may have been slower at the beginning, and hence the age would be earlier. Also, the full depth may be greater, owing to some borings hitting on ground which was originally above the river. Hence the extreme limits of age of Nile deposit in different positions are perhaps 7,000 to 15,000 years, and probably about 10,000 years may be a likely age for the beginning of continuous Nile mud stratification. Hence it is clear that the start of the civilisation was about contemporary with the first cultivable ground. [Sidenote: Stone Age in Egypt] [Sidenote: The First Dwellers in the Land] Earlier than the Nile deposits there must have been some rainfall, enough to keep up the volume of the river, and to prevent its slackening, so as to deposit its burden. We must picture, then, the country as having enough rainfall for a scanty vegetation in the valleys, while the Nile flowed down a mighty stream, filling the whole bed as it now does in flood, and bearing its mud out to the sea, except in some backwaters which were shoaling up. Such a land would support a small population of hunters, who followed the desert game and snared hippopotami in the marshes. The Nile had been in course of recession for a long period before it began to rise again by filling its bed. The gravels high above the present Nile contain flints flaked by human work; much as in Sinai such flakes are found, deep in the filling of the valleys which belong to a pluvial period. Yet after the Nile had retreated down to the present level, man appears to have been still in the Palæolithic stage, as freshly flaked, unrolled flints have been found at the lowest surface level of the desert. As the country, while drying up, and before mud deposits were laid down, would have only been suited for occupation by hunters, it seems probable that Palæolithic Man had continued in Egypt until the beginning of the Nile deposits--that is to say, till the beginning of the continuous civilisation as discovered in the cemeteries. BUSHMAN TYPE. On turning to the remains of the earliest burials, we find that in many cases female figures of the Bushman--or more precisely Koranna--type, were placed in the graves; while at the same time long, slender figures of the European type are also found. The inference is that the Palæolithic race of the Koranna type was known to the earliest civilised race in Egypt, and that they were being expelled and exterminated, as only female figures are found--representing captive slave women--and even these soon disappear. Thus it would seem that Egypt, as an almost desert region, before the formation of the cultivable mud flats, was the last home on the Mediterranean of the hunters who continued in the Palæolithic stage. The physical type of the figures which we can attribute to this earliest population has the Bushman characteristics of fatness of the thighs and hips, with a deep lumbar curve; and a line of whisker covers the jaws of the female figures, akin to the fur on the bodies of women on the Brassempouy and Laugerie-Basse ivory carvings. This indicates that they belonged to a cold climate, and had not been developed in Egypt. As, however, man had certainly dwelt in the Nile valley for long ages, this northern indication points to a comparatively recent invasion from a colder to a warmer climate, such as has been the rule throughout historical times. [Sidenote: Time Without Dates] PREHISTORIC PERIOD. The beginning of the continuous civilisation of the country must be placed at about 8000 B.C. The written history extends back to the first dynasty, and places that at 5500 B.C., and this is checked at the sixth, twelfth, and eighteenth dynasties by records of the rising of Sirius, and of the seasons in the shifting year, which agree to this dating in general. For the length of the prehistoric age before these written records there is no exact dating. But, as in a given district of Egypt, where all the desert has been searched, the prehistoric graves are about as numerous as those made during the six thousand years of the historic time, at least 2,000 or 3,000 years must be allowed. The amount of change in every kind of production during this age is considerable; and as we can trace two cycles of civilisation, which usually occupy about 1,500 years each in the later times, it is likely that 2,500 years is too little rather than too long a period. As no definite scale of years can be used, the dating of the graves of this age is treated as a matter of sequence. From a careful statistical classing of the pottery, it is practicable to put about a thousand of the fullest graves into their original order; this series is then divided into 50 equal parts, and these are numbered from 30 to 80. Thus, sequence date 30 is the earliest type of graves yet found, and S.D. 80 is of the age of Mena, the founder of the first dynasty. The sequence dates are given below for each stage of the prehistoric times. [Illustration: THE FIRST INHABITANTS OF EGYPT As female figures of the Bushman type are found in the very earliest Egyptian graves, it is thought that this race was native to the country and was gradually expelled by the first civilised people. The photograph illustrates one of the figures taken from a grave. ] EARLIEST BURIALS. The earliest graves found are shallow circular hollows on the desert, about 30 in. across, and a foot deep. The body lies closely doubled up, wrapped in goat-skins. There are very few objects placed with these burials; a single cup of pottery, red, with black top; rarely, a slate palette for grinding face-paint; and, in one grave, a copper pin to fasten the goat-skin. Pottery was in a simple stage, and weaving was quite unknown. These graves are classed as sequence date 30. [Illustration: POTTERY OF FIRST EGYPTIAN CIVILISATION The pottery of the first period of Egyptian civilisation is characterised by raised white lines on a red body, and from the fact that it closely resembles the pottery of the Kabyle people, who live in North Africa to-day, it is thought the first Egyptian civilisation may have come from the west. These examples are before 7000 B.C. ] [Sidenote: Civilisation Emerging from the Mists] FIRST CIVILISATION. The next period is that of the white patterns on red (S.D. 31 to 34). This use of lines of raised white slip is the same as on the present Kabyle pottery, and the patterns are so closely alike on the ancient and modern that this forms a strong evidence for a Western connection of the people. In this period the main lines of the civilisation become clearly marked. The fine flint chipping with delicate serrated edges; the polished red pottery, of circular and of fancy forms; the tall round-bottomed stone vases; the slate palettes for face-paint, of animal forms and of rhombic shape; the use of sandals; the ivory combs with animal figures; the disc-shaped mace-head--all of these were in use with the white cross-lined pottery, and stamp the general type of the beginning of the civilisation. We have before us a settled population, with strong artistic taste in handicraft, but not in copying Nature; with patience for very long and skilful work, and probably organised, therefore, under chiefs who commissioned such labour; yet with sufficient general demand for fine things to have raised hand pottery to its highest level; with strong beliefs about a future life, as shown by the uniform detail of the position of the body and the nature of the offerings in the grave; with the arts of spinning and weaving; fairly clothed, as shown by the use of sandals; fighters, with finely-made and treasured weapons; with the use of personal marks for property--altogether much in the stage which we now see in the highest races of the Pacific or Central Africa. EASTERN INVASION. This civilisation had lasted for a few centuries when we see a change come over it. On searching the types of pottery we see many new forms arising from S.D. 38 to 43, while many older types disappear between S.D. 40 and 44. These changes serve to stamp the point of the change, but it is in other respects that the differences are most visible. The black-topped pottery, red polished, and fancy forms of pottery cease to develop after 43, whereas the decorated pottery, with brown line patterns on buff ware, is scarcely known till 40, and the late class of pottery begins at 43. In the stone vases the forms of tall tubular shape, with handles, cease at 40, and the barrel forms begin at 39, and are dominant by 42. In flint work the various new types begin from 39 to 45; the disc mace dies out about 40, and the pear-shaped mace begins at 42. In the slate palettes old types vanish and new ones arise from 37 to 42. The same is seen in ivories. Foreign intercourse was increased, as silver (from Asia Minor?), lazuli (from Persia?), serpentine and hæmatite (from Sinai?) all come into use from 38 to 40. In copying Nature, the steatopygous figures of the Bushman type are only found before 38, and human figure amulets are known from down to 44. Animal figure amulets begin in 45. Multiple burials in graves are common down to 40, and continue till 43; only single burials are known later. [Sidenote: Invasion from the East] [Sidenote: What Mythology Says] The racial changes that are thus indicated by these widespread differences can only be traced by the different products. The white line pottery characteristic of the earliest people is closely like that of the Kabyles, and the similarity of the skull measurements show that there is no bar to accepting the connection with the North African race. But the details of the new people, using animal amulets, a face veil, wavy-handled pottery like that of early Palestine, and the Asiatic silver and lazuli, all point to their coming in from the East. This change may be further linked with the religious traditions. This later mythology taught that Osiris had found the Egyptians in a brutal existence, and he had taught them agriculture, laws, and worship; this appears to be the tradition of the bringing in of cultivation by the earliest civilisation at S.D. 30. His worshippers were allied with those of Isis, who were a kindred tribe. Hence Osiris is said to have married his sister Isis. The myth further shows that this civilisation was attacked treacherously by the tribe who worshipped Set, in confederacy with an Ethiopian queen, and they succeeded in suppressing the worship of Osiris and removing his remains to Byblos in Syria. This seems to agree to the influx of Asiatic influence, about S.D. 40, which we have noticed above. The correction of the calendar from 360 to 365 days, is attributed to the beginning of the civilisation (at S.D. 30) by the myth that Osiris and his cycle of gods were born on the extra five days. [Illustration: PREHISTORIC SHIPS: THE EARLIEST PICTURES OF EGYPTIAN VESSELS The pottery of the second period of Egyptian civilisation is rich in representations of prehistoric ships. The vessels are shown with many oars, and the cabins are placed amidship with a gangway between. It is gathered from these crude drawings that in prehistoric times there was a considerable shipping trade along the coast of Egypt. ] SECOND CIVILISATION. The second prehistoric civilisation, of which we have traced the Asiatic source, is specially marked by the use of a hard buff pottery, on which designs are often painted in brown outline. The art of these has no connection with that of the early white line designs; the habit of covering figures with cross lines, and the imitation of basket-work, have entirely disappeared; and, on the contrary, the plant, ostrich, and ship designs are quite new. What, then, were the connections of these people? One indication is gleaned from carvings at the close of the prehistoric age. Two tributaries of the new king of Egypt are shown bearing stone vases of the style of those of the second prehistoric civilisation, S.D. 45-75. They have large pointed noses, and wear pigtails, and another tributary of the same type wears a long robe. Hence we may see that they came from a cold region where stone vases were wrought; and that by the form of the vase they were probably the same people as the later prehistoric stock. Yet, on the other hand, we occasionally find pottery vases of that people in the earlier prehistoric age, so that they must have been in touch with Egypt throughout. The more likely source for them was the mountainous region, where snow sometimes lies, between Egypt and the Red Sea; and certainly this was the source of the rare igneous rocks used for the prehistoric vases. The general conclusion would be, then, that a people occupying the mountainous region east of Egypt had an independent civilisation, and were in touch with the early prehistoric people of the Nile valley. Then about S.D. 38 they began to push down into Egypt, and fully entered it by S.D. 44, bringing with them various different points of their own civilisation, and expelling the Osiris worship in favour of Set, who was their god. They probably brought in the Semitic elements to the Egyptian language, along with the other Asiatic connections. [Sidenote: Fleet of Prehistoric Ships] SHIPPING. Under this new order of things we see much more foreign and maritime connection. The introduction of silver from Asia, of lazuli from Persia, of hæmatite from Sinai, of serpentine from the Arabian desert--all show this. On the vases we see the starfish painted, and one of the most usual decorations was the figure of a great galley or ship. These ships are shown with oars on the pottery vases, and without oars or sails on the tomb paintings. From the proportion of the figures they appear to have been as much as 50 ft, long, and this is confirmed by the oars, which number up to sixty. Neither indication is exact; but the tendency would be to exaggerate the size of the figures, and certainly not to diminish them, and so aggrandise the ship. The shipbuilding in the early history may prepare us for the earlier rise of such work, when we read of Senefru building sixty ships of a hundred feet long in one year. [Sidenote: What the Ships Were Like] These prehistoric ships were all of one pattern. Amidships were the large cabins, and there was no poop or forecastle structure, probably because of the want of support fore and aft, the flotation being mainly in the middle. The two cabins were separated by a broad gangway across the boat, and joined above the gangway by a bridge from roof to roof. Lesser cabins projected fore and aft from the main cabins. On the roofs were rails at the corners, so as to secure top cargo without getting in the way of loading it up. In a large ship there was an upper cabin on the hinder main one, a light shelter shaded with branches. From the back of the hinder cabin stood up a tall pole bearing a solid object as a standard, which we shall notice below. At the stern was the steersman seated by an upright post, to which was probably lashed the steering oar, as in the historical boats. In the bows was a low platform, with a rail round it, for the look-out, shaded with branches. The cabins were narrower than the beam, and left free space for rowers on each side. [Sidenote: Trade in Those Days] FOREIGN IMPORTS. Vessels of this large size certainly imply a corresponding importance of commerce. We have noted already the foreign imports into Egypt; and others imply more distinctly a sea intercourse. From S.D. 33 down to S.D. 68 there is found black pottery with incised basket-work patterns [page 238] filled in with white. It is always rare, only occurring in less than 1 per cent. of the graves, and in only one case was there more than a solitary example. It is entirely disconnected from the Egyptian types, but it is closely akin to pottery found on the north of the Mediterranean, in Spain (Ciempozuelos), in Bosnia, and in the earliest town of Troy. At the close of the prehistoric age the black pottery of the late Neolithic city of Knossos is found in the lowest levels of the temple at Abydos. And in the royal tombs of the first dynasty there many vases and pieces have been found which are clearly of the earliest age of painted Ægean pottery. Considering that the bulk of the trade must have been for perishable goods--oil and skins from Crete and Greece, corn and beans from Egypt--it is not to be expected that a great amount of breakable pottery would pass and be preserved in burials. There are, moreover, some tallies left to us besides the northern pottery. Throughout the later prehistoric age emery was regularly in use for all the grinding and polishing of stone vases and of carnelian beads; and so common that one excelsior spirit in search of a tour de force had even cut a vase out of block emery, as being the hardest known material. This emery, so far as we know, must have come from Smyrna. Again, the gold of the first dynasty contains a large amount of silver. This points to its source from the Pactolus region, where electrum was found, rather than from Nubia, where the gold is free from silver. CONNECTION OF THE SHIPPING. When we look at the evidence of the ships themselves we see that it points to their having been used at sea rather than on the Nile. It is impossible to row a ship up against the Nile stream, which runs at three miles an hour, and sailing or towing is the only way to go southward in Egypt. But in only one instance is a ship with a sail represented, while there are many dozens of figures of rowing vessels. The galley has always been the type of business ship on the Mediterranean. All through the classical wars the rowing galley was the mainstay of power. The Homeric catalogue of ships, the Phœnician coinage, the Assyrian sculptures, the Greek fleets, the Carthaginian navy and its destroyers of Rome, the pirates of Liburnia and Lycia, down to the Venetian fleet and the French galleys of a couple of centuries ago, all show the dominance of the oar. [Illustration: ARTICLES ILLUSTRATIVE OF THE EARLY CIVILISATION OF EGYPT (1) Slate palettes on which paint for rubbing round the eyes was ground; (2) adze heads and harpoons, the harpoons at the sides being of bone, the others of copper; (3) beautifully flaked flint knife; (4) serpent amulet of stone; (5) maces of quartzose rock, very effective weapons; (6) forked lances of flint; (7) combs of ivory; (8) vases carved from hard stone; (9) black incised pottery, a foreign import into early Egypt. ] [Sidenote: Port Ensigns Carried] The nature of the standards upon poles carried by the ships has been variously interpreted. We can distinguish the elephant, bird on a crescent, and fish; the two or four pair of horns, the bush, and the branch; the rows of two, three, four, or five hills; the crossed arrows, and the harpoon, besides other forms which we cannot identify. The question is, what view will account for these most completely? Some have thought they were emblems of gods, and that the boats were sacred to divinities; but there are many which cannot be thus explained. Others have thought that they indicated tribes; but the rarity of repetitions, and the absence of any duplicates together, are against this. Marks of personal ownership have been suggested; and this is not impossible, as they might be well dedicated to special gods. But the prominence of the groups of hills as signs agrees best with their being marks of the ports from which they hailed; the divine emblems would naturally be those of the god of the port, the number of hills would be very likely to distinguish different ports, the elephant, the bush, or the fish might well be the mark of a port. And the parallel in later times of such being distinctive ensigns for ports--as in the ensign of Gades found in the Red Sea--agrees to this usage. The carrying of a port ensign in an age of independent city-states was equivalent to a national flag in later times; and it was essential for showing friends or foes. We have dwelt at length on the detail of this shipping, as it is the most important subject for showing the extent and character of the early civilisation. It takes two to trade as well as to quarrel; and these large ships were not rowed about the Mediterranean unless there was a paying trade to be done on those coasts, a people civilised enough to produce goods that were wanted and to require foreign stuff in exchange, and a society stable enough to enable goods to be stocked in bulk and traded without any serious risk of fraud or force. [Sidenote: Ingenuity of the Hunters] [Sidenote: Mode of Ostrich Hunting] HUNTING. The main occupation represented in the prehistoric paintings is hunting. The bow and arrow was used. The bow was a single piece of wood, painted red and covered with zigzag white lines; the arrow was of reed, with a point several inches long of hard wood. The forked lance of flint was also a favourite weapon [p. 238]; it was inserted at the end of a wooden shaft, which was controlled by a long thong of leather ending in alabaster knobs which kept it from entirely flying from the fingers. Thus the lance could be thrown by a man in ambush to cut the legs of a gazelle, while, if it missed, it was jerked back by the elastic thong, and so saved from breaking the delicate edge of flint. These forked lances are found throughout nearly all the prehistoric time; and they continued in use in North Africa till the Roman Age, when Commodus borrowed thence their use for hunting the ostrich. This lance retained by a thong was the parallel to the favourite harpoon used in fishing. Another mode of hunting was the trap. This is represented as being formed of pointed splints or stakes, lashed together like spokes of a wheel, with the points around a central hollow. Such traps to catch the legs of animals are used now in Africa, and an example was found at the Ramesseum, dating perhaps from the twentieth dynasty. Sticks or clubs were used in hunting and in fighting. [Illustration: STANDARDS OF EGYPTIAN SHIPS There has been much speculation as to the significance of the standards carried by the most ancient of the Egyptian vessels, as recorded on pottery and elsewhere. Some examples of these standards are here given. The most reasonable supposition is that these devices indicated the port from which the vessel sailed. ] FIGHTING. The earliest representation of fighting is on a vase of the white slip on red, at the beginning of the prehistoric age. On that a man with long, wavy hair appears to be spearing another man in the side. Later, there are the fighters on the Hierakonpolis tomb, at about S.D. 63. On this hooked sticks are used, and the fighters are clad with a spotted animal’s hide on the back. One man has been killed, and another is hard pressed, fallen on one knee. To save himself from blows he has taken off the hide and is holding it up, thus anticipating the use of the shield. It seems likely that the Egyptian shields of hide stretched on a frame of sticks were directly copied from this use of the hide that was otherwise worn on the body. In another group a black man is holding three red captives bound with a black cord, while two red men approach him to deliver their kindred. [Sidenote: Fighting with Maces] The weapons mostly found are the stone maces [page 238]. These were sharp-edged discs in the earlier age, a form which is very effective in a mixed fight, as it cannot be turned aside like a battleaxe, but must cut in whatever direction it falls. These maces were usually made of porphyry and other quartzose rocks. The mace used in the later age was of a pear shape, and this form was continued into the historic times, and perpetuated in the conventional scene of the king striking an enemy, even in the latest times. The handle holes in these maces are very small, and this shows that probably the handles were dried thongs of hide. Nothing else would be sufficiently tough and elastic. The flint dagger was probably also used, and certainly the copper dagger. A very fine example of this, dated to S.D. 55 or 60, is wrought with a quadrangular blade, giving the utmost strength and lightness, a better design than that of any daggers of the historic times. [Illustration: THE FIRST PICTURES OF FIGHTING The earliest representation of fighting, at the beginning of the prehistoric age, shows a man with long, wavy hair, spearing another man in the side. Later, are fighters on the Hierakonpolis tomb, using hooked sticks and clad in piebald hides of animals. ] TOOLS. Tools of metal begin with small, square chisels of copper at S.D. 38. The intermediate examples have not been found till we reach a fine large chisel of copper at the close of the prehistoric. Adzes of copper [p. 238] begin at S.D. 56, or earlier, and increase in size down to historic times; they continued to be the favourite tool of the Egyptians for both wood and stone working until Greek times. Borers are usually tapered, to work in soft material. Needles of copper appear as early as S.D. 48, and the fastening pins of copper begin with the very earliest graves of S.D. 30. Flint working was the greatest artistic industry of the prehistoric age. The surfaces were not merely reduced by haphazard flaking, but the flints were ground into form, and then reflaked in a marvellously regular manner with uniform parallel grooves [page 238]. The finishing of the edges by deep serrations of the fineness of forty to the inch, and the chipping out of delicate armlets of flint, show also the same astonishing skill and perfection of hand work. The Scandinavian flint chipping used to be regarded as the most perfect, but the Egyptian work entirely surpasses it in regularity and boldness. STONE VASES. Hard stones were largely employed for making vases [page 238]. In the earlier age tall, cylindrical forms were used, and in the later age barrel forms. The earlier material was usually basalt, but syenite, porphyry, alabaster and limestone were also used. The later materials included slate, grey limestone, breccia, serpentine, and diorite. The hollowing out of these vases was by grinding, but the outside was entirely formed by chipping and polishing without rotary motion. The perfect regularity of the forms, and the fine taste shown in the curves of the outlines, as well as the hardness of the material, place the vase working higher than any work of the historic times. [Sidenote: 1,000 Forms of Pottery] POTTERY. Pottery was greatly developed, although the wheel was not used, and all the forms were entirely modelled by hand and eye without mechanical guidance. The outlines are true and fine, the circularity is astonishingly regular, although all the trimming and polish runs vertically; and it was as easy in such a mode of building to make oval, doubled, or square forms, all of which are found. The specially later pottery is the decorated, with brown-red lines on a hard buff body. The forms are clearly copied from those of the stone vases; and the patterns are derived from the fossils and veins in the stone, or from the cordage net in which the vases were slung for carrying. Next appear aloes and other bushes, and figures of ships, which we have already noticed. Rows of ostriches and of hills are also favourite designs. Other pottery of this ware, but not decorated, has a curious type of projecting ledge, wavy up and down, for handles. Beginning at S.D. 40 as a globular vessel, the type narrows to an upright jar; by S.D. 60 the handles dwindle, becoming united around it as a wavy band of pattern; by S.D. 70 the jar at last becomes a cylinder; by S.D. 75 the band becomes a mere line; and then after S.D. 80--in the first dynasty--the jar dwindles to a rough tube like a thumbstall. The contents of such jars similarly deteriorate. At first, perfumed ointment was put in them, then it was covered with a layer of mud to retain the scent; the mud increased until it was merely scented mud, then only plain mud was used, and lastly they were left empty. Beside many other forms of this hard ware there was also a long series of types in a rough brown pottery, which passed on into the ordinary pottery of the first dynasty. As there are over a thousand different forms of this prehistoric pottery known, and their study has been the key to the whole arrangement of that age, this subject is a very wide one, which we have barely noticed here. [Illustration: PREHISTORIC POTTERY OF EGYPT The later pottery of the prehistoric period is characterised by brown-red lines on a hard buff body. The forms and decorations have been copied from earlier stone vases, and from the nets in which they were carried. ] [Sidenote: A Constant Personal Possession] SLATE PALETTES. A constant personal possession was the slab of slate upon which the green malachite or red ochre was ground for colouring around the eyes. Usually a brown pebble crusher accompanies it; and the dead often have a little leather bag of malachite in the hands. These slate palettes begin with a plain rhomb form, probably derived from the natural cleavages of the slate rock. Well-formed animal figures were also carved as slate silhouettes; the deer, hippopotamus, and turtle are the oldest, and the fish also comes into the earlier age. The double bird type begins with the second age, and all the types continuously degrade by repeated copying until their original form is quite indistinguishable at the close of the prehistoric age [page 238]. PERSONAL OBJECTS. Ivory carving is common, mainly for long combs to fasten up the hair. These usually have an animal on the top of them; but they only belong to the earlier age, suggesting that the hair was worn shorter in the second period. Decorated tusks of ivory are also early; they were fastened on to leather work, probably to close the openings of water skins. Ivory spoons belong only to the second period, as likewise do the forehead pendants of shell. Amulets of animal forms were frequent in the second period. They are generally cut in stone, carnelian, serpentine, porphyry, and coloured limestones. The forms are the bull’s head (which continued in use into historic times), the hawk, serpent [p. 238], frog, fly, scorpion, claw, vase, and spear head. The meanings attached to them are quite unknown. Games are found, as shown by the ivory draughtsmen, the small balls or marbles, the stone gateway and ninepins [page 242], the figures of lions and hares, and the throwing slips for obtaining a count as with dice. [Sidenote: What the People Wore] CLOTHING. The clothing of men was, at most, the kilt of linen, or an animal’s hide put over the body. Often only a belt was worn, with three narrow strips hanging down in front. A usual covering was a belt with a sheath attached to it to hold up the genitals. With the pleated kilt was also worn a belt having apparently a jackal tail hung behind. On some figures there is merely a double rope round the waist. These various forms may belong to different peoples and periods; but there are hardly enough examples to prove any distinctions, as the varying circumstance of the figures, captive and conquered, resting and working, rich and poor, in heat and in cold, may easily have led to the different dress that we see. Women are represented with a white linen petticoat from the waist to the feet. Leather was a favourite material for clothing, as well as for bags. It was painted with patterns, and decorated with beads, reminding us of the North American work. [Sidenote: The Oldest Capital of Egypt] DECAY OF CIVILISATION. All of this civilisation gradually decayed; the pottery is seen becoming coarser, good work dying out in rougher copying, new types seldom appearing, cheaper and poorer objects being more usual. There is ground, however, for supposing that at some time in this age there was a central rule at Heliopolis. There are many traditions of a principality there, which must certainly have been before the dynasties. The sacred emblem preserved in the temple was the shepherd’s crook, _haq_, which served for the title of “prince” in all later times; the other sacred emblem was the whip, and these two were the royal emblems of Osiris. The title of the nome was “the princes’ territory,” and this capital retained in later ages the reputation of being the centre of learning and theology. And on the fragment of the early annals known as the “Palermo Stone” there is shown a long row of kings of Lower Egypt before the dynasties; these cannot have ruled at Memphis, as that was a new foundation by Menes. [Illustration: THE EARLIEST GAME OF NINEPINS These ninepins, the gate to play through, and the porphyry balls were all found in a child’s grave. ] [Sidenote: History as Reflected in Mythology] [Sidenote: End of Prehistoric Times] HISTORY IN MYTHOLOGY. Of the breakup of this civilisation we may trace some relation in the mythology. After Isis had recovered the body of Osiris, and the worship of the Osiris and Isis tribes had revived again from the Semitic invasion of Set worshippers, Set again attacked the Osiris worship, and scattered the body of Osiris into fourteen parts in different places. This refers probably to the distribution of parts of the body to different districts, when it was cut up in the funeral ceremonies, according to prehistoric usage. These parts of Osiris were kept at sixteen nomes in Egypt in historic times, six in the Nile valley and ten in the Delta, probably the original nomes of the country. The civil discord implied in this persecution must have weakened the land; and then came the attack by the hawk worshippers from the south. In the legend of Horbehudti, or Horus of Edfu, we read that the crocodiles and hippopotami (animals of Set), attacked him, and his servants, armed with metal weapons, smote and conquered them, slaying 381 before the city of Edfu. Then the worshippers of Horus allied themselves with the sun worshippers, and “Horbehudti changed his form into that of a winged sun disc,” and “took with him Nekhebt the goddess of the South and Uazet, the goddess of the North, in the form of two serpents, that they might destroy their enemies in the bodily forms of crocodiles and hippopotami.” That is to say, the Horus, Ra, and serpent goddess tribes were all allied to attack the domination of the Set tribe. They gradually drove them back, and “Set went forth and cried out horribly”; he was finally struck down at _Pa-rehehu_. “Thus did Horbehudti, together with Horus, the son of Isis, who had made his form like unto that of Horbehudti.” That is to say, the rest of the Horus worshippers joined the Horus-Ra party. The final battle and expulsion of Set was at Zaru on the eastern frontier of Egypt. This, in mythological form, seems to give the history of the driving out of the Semitic population of the later prehistoric age, by the dynastic race descending from Upper Egypt, at the close of the prehistoric period. An actual result of this war, all through later times, was the multitude of towns named Samhud, or “United to Behudti,” marking the allies of the Horus party. HISTORICAL SLATE PALETTES. Of the period of the conquest by the dynastic races, which closed the prehistoric age, there is an invaluable series of monuments carved on slate. These carved slates are the elaborated outcome of the slate palettes used for grinding the face paints throughout the prehistoric age. A similar elaboration of a simple article is familiar in modern times in the snuff-box. A plain receptacle of bone or wood was decorated, plated, made of silver and of gold, inlaid with diamonds and painted with the costliest miniatures, and yet--it was but a snuff-box. So the plain slip of slate was carved into animal outlines, had animals scratched on it, then signs in relief upon it, and at last was covered with the most elaborate carvings, and yet--it was but a paint grinder, and had always the pan for colour carved on it, exactly of the shape of the pans on the painters’ palettes of that age. Every stage can be shown, from a formless slate to an artistic scene in relief. There are many stages to be seen in the artistic development. A. In the prehistoric age are the scratched outlines. B. The well-incised elephant is as early as S.D. 33-41; and with it are those signs in low relief. C. The high relief sign is of S.D. 60-63. D. On the boat slate, the drawing is much more detailed than on the boats of the Hierakonpolis tomb of S.D. 63. We can hardly separate this from the work of the artistic new-comers, and it may well be about S.D. 70-75. E. The animal slate seems to be next, as the treatment of the lion’s hair is unlike the following. F. The four-dog slate, being a coarser but more elaborated design of the same type, may well be next. G. The hut slate shows for the first time the arrangement of lion’s mane as on the ivory lions of King Zer. H. The gazelle slate shows the same treatment more advanced. J. The towns slate shows the wiry detail of muscles, beginning to appear in archaic manner. K. The bull slate has the same style carried out fully and finely. L. The Narmer slate has a less forcible and smoother treatment of the bull, and brings us down to touch with the historic times. The figures can be seen in Capart’s “Primitive Art in Egypt,” where they may be identified by these letters, corresponding to the paragraphs above: A, B, figures 61, 62; C, 63; D, 169; E, 171-2; F, 173-4; G, 170; H, 177-80; J, 175-6; K, 181-2; L, 183-4. RACIAL TYPES. These slate carvings not only show the art of the time, but they present the different races and the details of their life, more fully than we find them for many centuries later. We see six different types of physiognomy in the early remains, and learn how complex the racial history must be at the most remote period accessible to us. A. The _aquiline_ type is that of the principal prehistoric race, closely like the Libyan on the west and the Amorite on the east. When mixed with negro it produced the exact type of a European-Negro mulatto. Probably equal to the Libyan. [See Heads 1 to 4 on next page.] [Illustration: EGYPT IN THREE PERIODS OF ITS CIVILISATION This map of Egypt shows Egypt in three of its early periods. (1) The earliest centres of culture were at the places where parts of Osiris were preserved in the prehistoric age, here named. (2) The second period is shown by other centres being placed in the right geographical order, all here numbered I to XIX, following down each branch of the Nile. (3) The third period is when other centres were inserted in the lists in the wrong order, here numbered 8 to 20. These three stages of Egypt’s history are all before the monarchy. ] [Illustration: THE EARLIEST PORTRAITS OF VARIOUS RACES IN EGYPT Numbers 1 and 2 are the aquiline type, similar to 3, the Libyan, and 4 the Amorite. 5 is the curly hair type, 6 the sharp-nosed type, 7 the short-nosed type, 8 the forward beard type, 9-11 the straight-faced type of dynastic conquerors. 12 is King Khafra of the Pyramid age, reverting to the original type of 1 and 2. ] B. The _sharp-nosed_ type, firstly, with the hair in a pigtail, bringing stone vases as tribute, and sometimes dressed in long robe; secondly, with bushy hair and armed with spear, throw-stick, mace, bow and arrows. Probably the Arabian mountain race mixed with Libyan. See figure 6 on this page. C. The _curly hair_ type, with plaited beard, conquered and destroyed by type B. Probably from North Syria, by sculptures there. See figure 5 on this page. D. The _forward beard_ type, with close-cut hair; much like the figures on early Naukratite vases. Probably a coast people of Libyan connection. See figure 8 on this page. E. The _short-nosed_ type, a variety of D, apparently belonging to the Fayum. Fig. 7. F. The _straight-faced_ type of the dynastic conquerors. See figures 9-11 on this page. All of these different peoples were in continual mixture and struggle during the few centuries before the first dynasty. Looking to the tribal hints given by the mythology, it seems probable that: A represents the early Osiris and Isis worshippers; B the first dominance of Set; C the second irruption of Set; D and E the allied Osiris and Isis worshippers of the Delta and coast who helped to expel Set; and F the hawk Horus worshippers, who took the lead in driving out B and C by alliance with A, D and E. [Sidenote: Earliest Promise of Greatness] DYNASTIC RACE. The most essential difference between the prehistoric and the dynastic people is in their artistic capacity. The earlier peoples, though highly skilled in mechanical detail and handling, were yet very crude in their copying of any natural forms. But as soon as we reach the dynastic race we find that there is an artistic sense and power in their work, which puts even the roughest of it far above all that had gone before. The earliest examples of their sculpture appear to be the colossal figures of the god Min, found at Koptos. These are of the most primitive style possible, the limbs scarcely marked off from the trunk, and no details of form attempted. But on the side of each there is a patch of hammer-work outlining some figures, perhaps a copy of embroideries on a skin pouch hung at the side. These are figures of a deer’s head and pteroceras shells on one, swordfish, shells, and standards of the god on another, and the same objects, together with an ostrich, elephant, hyena, and calf on the third. All are but roughly hammered round, yet the spirit and correct forms of the animals are of an entirely different order from anything that had yet appeared in Egypt. The promise of all the artistic triumphs of thousands of years to come is clearly seen in these decorations of the rudest statues known. [Sidenote: Mystery of Dynastic Race] The source of this dynastic race can only be inferred. Though marked off from the earlier inhabitants by their artistic taste, and by their use of hieroglyphic writing, we know so very little of the early history of any other lands near Egypt that we cannot yet trace any link to their original source. On looking in various directions, it seems at least clear that they do not belong to the southern tribes, to which they have no resemblance; nor can we suppose that the Libyans, who appear to be one with the prehistoric people, would also supply a race so different in face and in habits. The north and Syria seem barred by the earliest centres being at Abydos and Hierakonpolis in the south of Egypt, from which they conquered the north. [Illustration: THE FIRST PROMISE OF THE ARTISTIC TRIUMPHS OF EGYPT These animal figures were wrought by hammering around on the surface of the colossal statue of the god Min, found at Koptos, and show the beginning of the wonderful art of Ancient Egypt. It is the work of the earliest dynastic people, who have passed beyond the stage of making rude scratches on walls and on pottery, and have arrived, as the figures of the ox and the hyæna prove, at a real conception of the methods of sculpture. ] [Sidenote: The Way the Conquerors Came] Lastly, no source seems open except the East, the road from which joined the Nile at Koptos. It is there that the earliest statues have been found, and the decoration on those comprises the swordfish and pteroceras shell belonging to the Red Sea. Such seems to have been the road of the dynastic race into Egypt; but the origin of that race yet awaits research. There are undoubtedly some Babylonian elements in their culture, and somewhere at the south end of the Red Sea lay Punt--the “divine land” of the Egyptians. Thus we are tempted to look to some migration from Southern Arabia, whence also may have proceeded the kindred Sumerian culture, a few centuries later. From this centre in Pūn, or Punt, it may have conquered and colonised Egypt, and then later passed on up the Red Sea to the coast of the Pœni and their later Punic colony--Phœnicia and Carthage. Such is a pleasing co-ordination, but whether we shall ever recover the evidence to prove or disprove it hangs upon the chance of the past and the activity of the future. CONQUEST OF EGYPT. The conquest of Egypt spread down from the south to the north. The earliest centres were Abydos and Hierakonpolis. Probably Edfu was as important, or more so; but the great Ptolemaic temple there being still complete, the remains of the earliest kingdom are sealed beneath its pavements. The conquest must have been a gradual process; it is described as such in the myth, many times and in many successive places was Set defeated and repelled. And the probability is that tribal war of such a kind would only gradually transfer district after district from one holder to the next. We know how in England the conquest occupied three centuries, from the Saxon landing to the first Saxon king of all the land. So it may well have been in Egypt. [Sidenote: Kings Before History] We read in Manetho of ten kings of Thinis (Abydos) who ruled for 350 years before the first dynasty of kings of all Egypt. And we know, from the fragment of the Palermo Stone, that at least thirteen kings of Lower Egypt were recorded before the first dynasty. It is obvious from this, and from the probabilities of the conquest, that there were Kings of Upper Egypt before the first dynasty; and there is no reason for not accepting this statement of Manetho as being equally correct with his account of the first dynasty, which we can verify. Of the actual course of the conquest, one fragment of carved slate has preserved the record. Seven towns are represented upon it, each attacked by one animal of the standards of the allies. These towns may be tolerably identified by comparing the hieroglyphics placed within them with the names known in historic times. The upper row of four towns seem to be Mem in the Fayum, Hipponon, Pa-rehehui, and possibly Abydos; and the lower three towns were probably in the delta, though there are the uncertainties of two northern similar names. [Sidenote: Graves of Unknown Kings] DYNASTY O. The contemporary remains that appear to belong to this age of the Kings of Abydos (which we may call Dynasty O) are the tomb chambers and funeral objects in the royal cemetery at Abydos. The plan of that cemetery shows a sequence of each later tomb being placed next to the previous tomb, and generally a receding further back into the desert as time went on. Now, in front of the tomb of Zer, the second king of the first dynasty, there are three large tombs alike, and four lesser ones. As objects of Mena, the first king, were found here, the other tombs are presumably those of six kings before the first dynasty, by their position. The actual objects found in these tombs are all of a more archaic style than those of Mena or any later king. The tombs themselves are all lesser and simpler than those of Zer and later kings. And the names of kings found here are all without the vulture and uræus title, but with only _neb neb_, the double lordship of Egypt. The whole of the evidence, therefore, goes to show that we have six tombs of the Thinite kings before Menes. The names of these earlier kings, so far as we trace them, are Ka, Ro, Zeser, Zar, Nar, and Sma. Of these, Nar, or Narmer, has the most important remains--part of an ebony tablet, and an alabaster jar from his tomb, and the great slate palette, a great mace head, with scene of a festival, and an ivory cylinder, from Hierakonpolis. The next in importance is Zar, or the “Scorpion King,” of whom there is a great carved mace head, and also some vases. The objects of the carvings appear to be celebrations of the _sed_ festival; this appears originally to have been the slaying of the king every thirty years, making him Osiris, one with the god, while his daughter was married to the new king. By the time of these carvings, it appears that the king took the place of Osiris in the ceremonials, and his successor masqueraded as the new king, and was henceforth the crown prince--the heir to the kingdom. [Illustration: A FESTIVAL SCENE OVER 7,000 YEARS AGO, IN THE REIGN OF KING NARMER, 5,500 B.C. A record of the festival of Narmer, a king of Abydos, who reigned before the first dynasty of kings of all Egypt. It indicates that when the festival of his own death was celebrated, in accordance with the ancient custom of killing the king every thirty years to make him one with Osiris the god, no fewer than 120,000 captives, 400,000 oxen, and 1,422,000 goats were offered. The numerical system is here seen to be complete up to millions. ] [Sidenote: Planting and Building] There were brought to the festival of Narmer 120,000 captives, 400,000 oxen, 1,422,000 goats; and the system of numeration was as complete before Menes as it was in any later time. The other mace head of King Zar shows part of the festival, and also the ceremony of the king hoeing the bank of a canal, probably at the inundation. We see the reclamation of the land, with men busy embanking the canals, and cultivating a palm tree in an enclosure of reeds, while they lived in reed huts with plaited dome tops, and used boats with a very high, upright stem. The carved slate palette of Narmer shows him grasping the chief of the Fayum, prepared to smite him, a scene which was repeated for five thousand years in all the Egyptian triumphs. The metal water-pot and sandals are carried behind the king by his body servant. On the other side of the palette is the king going to a triumphal ceremony, preceded by the scribe, _thet_, and four men of different types bearing the standards of the army, possibly connected with the four territorial divisions of the army found under Ramessu II. Before them lie ten slain enemies, with their heads cut off and put between their legs. The carving of the detail, and particularly the muscular anatomy of the king’s figure, is extraordinarily fine and firm, and as true as any work of later time. WRITTEN HISTORY. Having now dealt with the history as drawn from the remains which have come to light, we now enter from this point on the continuous written history, which has come down from hand to hand without a break to our own times, during over seven thousand years. This history was compiled by the high-priest and scribe Manetho of Sebennytos in the Delta, and only a fragment of his work has been preserved on its full scale; but three later writers have given epitomes of it, and it is on their lists that we have to depend. These are Julius Africanus (221 A.D.), Eusebius (326 A.D.), and George the Syncellus (792 A.D.). [Sidenote: The Men Who Handed Down the Story] [Sidenote: An Ancient Historian and His Figures] Unfortunately, much confusion has been caused by scholars not being content to accept Manetho as being substantially correct in the main, though with many small corruptions and errors. Nearly every historian has made large and arbitrary assumptions and changes, with a view to reducing the length of time stated. But recent discoveries seem to prove that we must accept the lists as having been correct, however they may have suffered in detail. A favourite supposition has been that the dynasties named were arbitrary divisions of later times; but the earlier lists also show such divisions as far back as the eighteenth dynasty, and kings founding a dynasty used to copy the titles of the founder of the previous dynasty, showing that the change was recognised at the time. Another idea has been that the dynasties were contemporary. But, on the contrary, in the overlapping of the tenth and eleventh and also the twenty-fifth and twenty-sixth dynasties, we can trace that Manetho was very careful to cut off from one dynasty all the time which he allows to another. As regards the general character of the whole length of time, we can show that Manetho’s version in 271 B.C. at Sebennytos was the same as that given to Herodotus two hundred years earlier at Memphis. Herodotus was told that from Menes to his time were 330 kings, and the totals of Manetho are 192 + 96 + 50 to Artaxerxes = 338, so that, in spite of corruption in detail, the totals seem to have been correctly maintained. In earlier times we can compare Manetho with the fragments of the Turin papyrus, written in the eighteenth dynasty; and here, in one of the most disputable points--the kings of the thirteenth dynasty--the average of eleven reigns legible in the papyrus is 6½ years, and Manetho states sixty kings in 453 years, or 7½ years’ average. The general character of a great number of short reigns in this age is quite supported. Then in the eighteenth dynasty there is a rising of Sirius in the movable calendar, in the twelfth dynasty another rising of Sirius, and some seasonal dates, and in the sixth dynasty are two seasonal dates. [Owing to the ignoring of leap year, the Egyptian months shifted round the seasons in 1,460 years; hence any seasonal date can only recur once in 1,460 years, and fixes an absolute date in that cycle.] All of these agree with Manetho; and though the seasonal dates are vague, they at least show that there is not an error of several centuries in the total. In the earliest times there is the account of the first dynasty, the names and succession of which are verified by the sculptured lists in the nineteenth dynasty and by the actual graves of the kings. Every accurate test that we can apply shows the general trustworthiness of Manetho, apart from minor corruptions. [Illustration: THE EARLIEST DETAILED SCULPTURE This carved slate palette of King Narmer shows him grasping the chief of the Fayum, prepared to smite him, a scene which was repeated for five thousand years in all the Egyptian triumphs. The sculpture shows anatomical treatment for the first time in art. ] [Sidenote: Material for History of Early Times] It is naturally a question what sort of material existed for an accurate history of the early times. The fragment of annals known as the Palermo Stone was engraved in the fifth dynasty, and it recorded the principal events of all the years back to the beginning of the kingdom, a thousand years before, the height of the Nile for every year, the length of every king’s reign and of interregnum to the exact days. With such a record of the most remote times carefully maintained we have every reason to suppose that the high-priests and sacred scribes had adequate information as to the general course of their history. And we can see by the Turin papyrus how in the eighteenth dynasty there was a full historical list of all the kings, with their length of reigns, dynasties, and summations of numbers and years at each of the large divisions. Thus it is proved that there were historians at various periods who compiled and edited the history, and so provided a solid groundwork for later writers, such as Manetho. [Illustration: A RECORD OF EVENTS IN 4750 B.C. A part of early annals known as the Palermo Stone. Each compartment contains the events of one year, with the height of the Nile in cubits stated below it. The lower right division records: “Building of a ship 170 feet long, and of 60 ships 100 feet long. Conquest of negroes, bringing 4,000 men, 3,000 women, and 200,000 cattle. Building a wall of the palaces of King Sneferu. Bringing 40 ships of cedar (from Syria).” The left division reads: “Making 35 hunting lodges and 122 tanks for cattle. Building a ship of cedar 170 feet long, and two other ships of 170 feet. 7th census of cattle.” ] [Sidenote: The Witness to Early Civilisation] The materials that we have for studying the civilisation of the early dynasties are the royal tombs and steles, the tablets of the annals, the sealings of officials, the inscribed stone bowls, glazed pottery, ivory, and wood, the rock steles of Sinai, fragments of buildings of the second dynasty and onward, the steles of private persons and their graves. [Sidenote: In the Kings’ Tombs] ROYAL TOMBS. The tombs show that brickwork was familiar on a large scale. The prehistoric houses and tomb chambers were by no means slight. The town at Naqada has house-walls about two feet thick, and a town wall nearly eight feet thick. The brick-lined tombs are sometimes as large as 8 ft. by 12 ft. The kings’ tombs of Dynasty O are about 10 ft. by 20 ft. Those of Narmer, Sma, and Mena are about 17 ft. by 26 ft., with walls 5 ft. to 7 ft. thick. Under Zer there is a great extension; the brick pit is 39 ft. by 43 ft.; it contained a wooden chamber 28 ft. by 34 ft., and it was surrounded by many rows of graves--318 in all. The later tombs of the first dynasty are less imposing. At the end of the second dynasty the tomb of Khasekhemui consisted of fifty-eight chambers covering a ground 223 ft. long and 40 ft. wide. The sizes of bricks were between 9 in. and 10 in. long, half as wide, and under 3 in. thick, in the prehistoric and through the first and second dynasties. Wood was used on a large scale. The royal tombs show beams for framing of about 10 in. wide and 7 in. deep, and 18 ft. or 20 ft. long, and these beams supported chamber sides and floors formed of planks 2 in. or 3 in. thick. The roof was made of similar beams, covered with boards and mats, which sustained 3 ft. or 4 ft. of sand laid over the tomb. Such was an extension of the roofs of poles and brushwood which were laid over the prehistoric tombs, and over the lesser tombs of the officials of the early kings. The sign for royal architect in the earliest inscriptions is that of a carpenter, the “two-axe man.” The stone steles were of limestone in the first dynasty, and in the end of the first dynasty the steles of Oa are of black quartzose stone. Those of Perabsen in the second dynasty are of very tough syenite. The carving of all these is in high relief, finely and boldly cut in a simple, clear style. At the end of the second dynasty a stone-built chamber appears for the first time; the blocks have naturally cloven surfaces so far as possible, and the rest of the faces are dressed with a flint adze. Of the same reign of Khasekhemui there is a granite door-jamb with signs in high relief. Granite had already been wrought flat for pavements in the previous dynasty, at the tomb of Den. [Sidenote: Egypt’s Annual Record] [Sidenote: The Honour that Kings Died for] TABLETS OF ANNALS. The greater part of the inscriptions of this age are on small square tablets of ebony and of ivory, which were found in the royal tombs. These each have a hole in the top corner, and the sign of a year--the palm stick--down the side, as there is by the side of the entries of the events of each year on the early annals. They thus appear to be each the record of a year, and to have been strung together by the corner holes. There has not yet been any authoritative study of the meaning of these earliest inscriptions, which are very difficult to understand, owing to the transitory condition of ideographs having not yet yielded to syllabic usage. We can, however, glean many points about the civilisation from them. The towns were fortified with battlemented walls. The shrines were small sanctuaries, with a large court in front, like the temple courts of later times. At the entrance to the court were two tall poles, apparently with flags, which later developed into the row of masts with streamers in front of the pylon. The great festival at the close of each thirty years was one of the most important, already noticed here under Narmer. The sanctuary for it had two shrines back to back, each with a flight of steps, apparently for Upper and Lower Egypt. The dancing of the new king, or the crown prince as king, before the old Osirified king in the shrine, was one of the main events of the feast. The types of temple furniture were already fixed in the forms which lasted for several thousand years; the barks of Harakhti are shown with the same hangings at the prow, and are double--for the E. and W.--as in the temple of Sety I. Large bowls of electrum were offered in the temples by the king. Wild cattle were hunted by trap nets, as was done much later in Greece. And there is shown a long road, with resthouses and palm-trees, leading up to the great temple in the reign of King Zer. [Illustration: A RECORD OF A YEAR’S EVENTS: EBONY TABLET OF KING MENA, 5500 B.C. The greater part of the inscriptions of the first dynasty are on small square tablets of ebony and of ivory. These each have a hole in the top corner, and the sign of a year--the palm stick--down the side. They thus appear to be each the record of a year, and to have been strung together by the corner holes. They were found scattered in the tombs. ] [Sidenote: Officers of the Empire] SEALINGS. The clay sealings of officials show much of the organisation of the country. The oldest titles, under Zer, are the “Commander of the Inundation” and “Commander of the Cattle.” In the reign of Zet we find a “Commander of the Elders” and “Archon,” or chief of the city; also the temple property, or “Inheritance of the Chief God,” is named. Under Merneit and Den there is a prince (_ha_). The vizier was “Commander of the Centre,” probably the major domo of the Court, and also “Over-head of the Commanders.” There are further named a “Royal Sealer of the Vat of Neit,” the “winepress of the north,” and a “Deputy of the Treasury.” In later reigns there is an “Over-head” of a city. And under the second dynasty the titles are “Royal Sealer of all Deeds,” “Scribe of Accounts of Provisions,” “Sealer of Northern Tribute,” “Collector of Lotus Seed,” and “Chief Man Under the King.” These titles are from but a very small part of the bureaucracy, only those whose seals were affixed to the royal provision which was placed in the tomb; but they suffice to show the regular organisation of the government at that age. [Illustration: THE SEAL OF AN EGYPTIAN OFFICIAL Much exact knowledge of the life of ancient Egypt is derived from the clay seals of high officials. The oldest known titles are those of “Commander of the Inundation.” The seal here is that of the “Southern Sealer of all Documents of King Sekhem-ab,” 5100 B.C. ] STONE VASES. The stone vases for the royal palaces were cut in many kinds of hard rock. The rarer kinds are rock crystal, serpentine, and basalt; limestones, porphyry and syenite were more usual; and the commonest materials were metamorphic rocks formed from volcanic ash verging into slate, dolomite, marble, and alabaster. These materials were mostly selected for their beauty. The red porphyry is the rarest, being only known in a bowl of the time of Mena, and two prehistoric pieces. Black porphyry with very large detached white crystals belongs only to the age of Mena. Pink granite, blue-grey volcanic ash, the quartz crystal, and the pink limestones are all very beautiful materials. The hardness does not seem to have been aught but an attraction, as the finest work is always put on the best materials; whereas the soft alabaster and slate did not seem to challenge any great amount of care. The working of the inside was always done by grinding with blocks, sometimes having first removed the axis by a tube drill hole. The outside was dressed by chipping, hammer-dressing, and hand polishing; sometimes done by circular motion on a block, but often by crossing work by hand. The readiness with which oval forms were made shows how little depended on circular motion. [Illustration: TOMBS OF KING ZER OF THE FIRST DYNASTY, 5400 B.C. Brickwork was common in the houses and tomb-chambers of the prehistoric period, and in the time of the kings of Abydos the building of the tombs was greatly extended. Here are seen the brick partitions to contain offerings, around a wooden chamber now destroyed. Beyond this all round were 318 graves of the royal servants. ] [Sidenote: Two-Colour Glazing] The use of glazing had been already invented early in the prehistoric age, as far back as S.D. 31; but it was only applied to beads and small amulets. The earliest glazed pottery vase known is of Mena, and this has his name in violet glaze inlaid in the green glazed body. Glazed vases continued to be made throughout the first and second dynasties, but became rarer, and they have not been found revived till much later times. But ivory and wood were largely used for carved objects, sometimes of elaborate design. One of the most distinguishing points of the age of the early kings was the minute carving in imitation of leafage and basket-work, which was mainly done in slate, but also in wood. The fragments which remain show most elaborate patterns worked out with minute attention to detail. Nothing of the same kind is known in any other age. [Sidenote: Remains of the Oldest Sculpture] MONUMENTS. There are but few monumental remains from these early dynasties. The great rock-cut scene of Semerkhet conquering a Bedawy chief in Sinai is the main example. The figures are only summarily cut in the natural face of the sandstone; but the truth of the outline is better than in any of the more pretentious work of later times in that region. The scene of Sanekht--early third dynasty--is much poorer, and that of his successor, Zeser, is scarcely legible, the work is so rude and slight. The private tablets which were put over the graves around the royal tombs show that the fine work was limited to a small number of royal artists in the first dynasty, and that there was no general school of able men such as arose in later times. The figures and hieroglyphics are rudely hammered out, and the drawing is but clumsy. There is seldom more than just the name of the deceased. By the time of Den many are distinguished as the _Akhu-ka_, the “glorious soul”; while there is also a class apparently named “people of King Setui, daughter of the captive”--_i.e._, slaves born of captives taken in his wars. [Illustration: THE EARLIEST SCULPTURE There are but few monumental remains from the early dynasties. The great rock-cut scene of Semerkhet, of which this shows a part, is the main example. The figures are only summarily cut in the natural face of the sandstone; but the truth of the outline is better than in any of the more pretentious work of later times in the same region. ] It appears that the use of fine materials was at its height under Mena and Zer. Zer has the largest and best-built tomb, Zet shows the greatest delicacy in work, and Den seems to have had the most showy objects. The changes in about five generations here were much like those in an equal time from Amenhotep I. to III. in the eighteenth dynasty. Then decay markedly set in, and there was no revival until the Pyramid kings. But some development in the use of materials went on; and Zeser, of the third dynasty, is said to have built a stone palace; while Khasekhemui, a generation earlier, had a limestone chamber for his tomb, and carved granite for the door-jambs of his temple, at about 4950 B.C. These instances are the earliest use of stone for construction that are yet known; though as early as the middle of the first dynasty King Den had a pavement of red granite in part of his tomb. [Sidenote: Age of the Pyramid Builders] PYRAMID BUILDING. We now approach to the well-known age of the pyramid builders, when the civilisation appears at its highest development in most respects. We shall not deal with this in detail, as it falls into the ordinary historical period which appears elsewhere in this work [see Egypt]. But it may be useful to give the most essential facts of the material civilisation, which may otherwise be lost sight of in the mass of the history. In stonework the accuracy reached its highest point in the fourth dynasty, when the Pyramid of Khufu was constructed with an average error of less than 1 in 15,000 of length, and even less in angle. The later work fell off from this accuracy; but in the twelfth dynasty the granite sarcophagus of Senusret II. was wrought with an average error in straightness and parallelism of under seven-thousandths of an inch, and an error of proportions between different parts of less than three-hundredths of an inch. There was no attempt to reach this high degree of accuracy in the later work. In sculpture the main character of the work of the Pyramid kings is its dignity and grandeur, representing individualism on the highest plane of abstraction. [Illustration: THE BUILDING OF THE PYRAMIDS IN THE ZENITH OF EGYPTIAN CIVILISATION The age of the Pyramid builders may be regarded as the height of Egyptian civilisation. The greatest accuracy in stonework was reached during the fourth dynasty, when the Pyramid of Cheops, or Khufu, was constructed with an average error of less than 1 in 15,000 of length, and of even less in angle. In the twelfth dynasty the granite sarcophagus of Senusret II. was wrought with an average error in straightness and parallelism of under seven-thousandths of an inch. ] [Sidenote: The Great Navy of Egypt] Under the twelfth dynasty the personality is weaker and the style that of a formal school, highly trained but dependent upon training. In the eighteenth dynasty the vivacity of expression is directed to a purely personal appeal, more of emotion than of character. After that there is nothing but copying, good or bad. The growth of shipping at the early date of Sneferu, the end of the third dynasty, is surprising; and the record that we happen to have shows how much probably went on at other times, there being built, in one year sixty ships of 100 ft. long, in the next year two of 170 ft. long. METALS. The use of copper is as remote as the beginning of the continuous civilisation in the prehistoric age, about 8000 B.C. It increased in quantity down to the eighteenth dynasty, and it was hardened by using arsenical copper ores, and leaving oxide in it; this, with hammering made it equal to soft steel for working purposes. Rare instances of tin, probably derived from natural mixture in the ore, are known from the third dynasty; but there was no regular use of it until we find pure tin, also known about 1500 B.C. Thence bronze was the main material until Roman times. Iron had been sporadically found in the fourth, sixth, twelfth, and other dynasties, and was known for about 4,000 years before it came into general use in Greek times. This agrees with its having been obtained from native masses rarely discovered, as has been the case in North and South America. Such native iron is the result of volcanic action on iron ore in contact with carboniferous strata. All these conditions exist in Sinai, and hence native iron might be found there. By about 800 B.C. iron was used for knives, but with a handle of bronze cast upon it to save the rarer metal. The iron tools in Egypt from the seventh to fifth century B.C. are all Assyrian or Greek, and it is not till Ptolemaic or Roman times that bronze tools disappear. [Illustration: TOOLS OF ANCIENT EGYPTIANS The plain strip of copper used for an adze in the early prehistoric age became in historic times widened at the edge, and had a slight contraction at the top; but the straight strip was kept up for 7,000 years without any attempt at a haft, simply lashed on to a bent handle. It is not till about 800 B.C. that any use of a haft occurs in Egypt, and then only for a hoe. The different dynasties are indicated in the examples here given. ] [Sidenote: Oldest Rock Drills] The forms of tools varied very little. The plain strip of copper, which was used for an adze in the early prehistoric age, became in historic times widened at the edge, and had a slight contraction at the top to assist in binding it on; but the straight strip was kept up for 7,000 years without any attempt at a haft, simply lashed on to a bent handle. It is not till about 800 B.C., or later, that any use of a haft occurs in Egypt, and then only for a hoe; while in Babylonia axes cast with a strong haft were used before 3000 B.C. Nor was a haft used for a hammer--a smooth stone in the hand was the only beating tool; while for striking tools a wooden mallet was used, cut out of a block. The axe began as a plain rectangle of copper, sharp on one edge; projections at the back were added, until they were half as long as the breadth of the axe, but no haft was attempted. The saw was used before the pyramid period; and also the saw and tube drill set with hard stones for cutting granite. Drills for boring vases were usually blocks of stone fed with sand and water, or probably emery for cutting the harder stones. Socketted chisels were an Italian invention in the later Bronze Age, about 900 B.C., and were copied by the Greeks, in iron, about 500 B.C.; but they were never used except under Greek influence in Egypt. Shears are also Western, and were unknown till Greek times in Egypt. [Illustration: ONE OF THE WORLD’S OLDEST MONUMENTS: THE GREAT STEP PYRAMID AT SAKKARA This pyramid was built by King Neterkhet of the third dynasty, about 4900 B.C. ] [Illustration: THE BEGINNING OF THE ALPHABET The signary which was used in various early ages is here shown, as it has been gathered from examples of over 100 signs found in Egypt. Closely related to these are the early alphabets of Karia and Spain, the latter alphabet containing over 30 signs. It is from this prehistoric signary that the present Roman alphabet has been gradually selected during past ages. ] GLAZING AND GLASS. The very ancient art of glazing, already used in two colours under Mena, did not take any new form till the eighteenth dynasty, when it was greatly varied by new colours and new applications. Large objects, five feet high, were covered with a single fusing of glaze; minute ornaments, for stitching on garments, blazed with the brightest red, green, blue, or yellow; while whole inscriptions were executed in coloured glaze hieroglyphs, inlaid in the white stone walls. Glass, however, was not made separately until about the time of Tahutmes III., 1500 B.C. There is no earlier example of true glass, nor any representation of working glass. All the truly Egyptian glass was wrought pasty, and never blown. Blown vases belong entirely to the Roman age and later times. The large blown glass lamps of Arab age, covered with fusible enamel designs, are highly skilled pieces of work. The uses of glass to the Egyptian were mainly for beads, for coloured inlays in wood of shrines or coffins, and for variegated glass vases. The beads were made by winding a thread of glass on a wire; the vases, likewise, were made by modelling on an infusible core, held on a mandrel, and winding coloured glass threads on the body. The inlays were often of one colour, generally deep blue imitating lazuli; but often mosaics were used, made of a bundle of glass threads fused together, drawn out, and then cut off in slices. Such are all of Greek or Roman age. An important use of glass in Roman and Arab times was for weights, and for stamps impressed on glass bottle measures, inscribed with the names of the ruler and the maker. [Sidenote: Taste of the Times] Lastly we may note the variations in the nature of the Egyptian literature, as reflecting the civilisation. The earliest tales are those of magical powers, belonging to the pyramid age. Next, in the Middle Kingdom, comes the contrast between town and country, and the tales of adventure in foreign lands. In the New Kingdom the contrasts of character are the main interest, and, in the late tales, the pseudo-historical romance of the great tournament of the Delta, or the antiquarian interests of a priest. These subjects of romance varied as much or more than the actual grammar and language. [Illustration: THE WANDERERS OF THE DESERT, AMONG WHOM EGYPTIAN CIVILISATION GREW UP] [Illustration: PYRAMID OF MEIDUM: BUILT BY SENEFERU, LAST KING OF THE THIRD DYNASTY This tomb was begun as a square block of masonry, and was enlarged by successive coats, which are here seen. Then one smooth coating of sloping blocks was put over all from bottom to top, and so the first real pyramid appeared in 4700 B.C. The pyramid coating has been destroyed and only the base remains under the rubbish mounds. ] ALPHABET. One subject of great European interest should be noted here, as Egypt has thrown much light upon it. The origin of the alphabets of the Mediterranean has been disputed, without historical knowledge of the examples of such signs in early ages. The Egyptian hieratic and the archaic Babylonian signs may have, perhaps, added a few to the Mediterranean signary, but neither source can at all account for it. The alphabet is by no means a clean cut series of 22 signs; it is a very complex tangle of parallel groups of signs in different lands, more or less alike. Of these groups two of the largest are those of Karia and Spain, comprising over 30 signs, and these have many points of peculiarity in common. This is sufficient to show that the fuller alphabet is the original form, from which the shorter lists have been selected. Now, in Egypt there are found scratched on pottery and woodwork over 100 signs, and these comprise the forms of the fuller alphabet. Moreover, these Egyptian examples are found at about 1200 B.C., or only a few centuries before the Karian and Spanish alphabets, again in 3000 B.C., in 5500 B.C., and before 7000 B.C. Of 41 alphabetic signs, 19 occur in 1200-1400 B.C., 32 in 3000 B.C., 27 in 5500 B.C., and 31 in 7000 B.C. As we have not a very large amount of material, the occurrence of from 19 to 32 out of 41 signs is as much as we could expect, as all the 41 occur in one period or another. The early date of these puts all derivation from the subsequent hieroglyphics entirely out of the question. We can as yet only say that a large signary of 40 or more linear forms was in continuous use from before 7000 B.C. downwards, and that these furnish all the forms of the fuller alphabets, those of the short Phœnician and Greek list of later time. We have now outlined the rise of civilisation in Egypt, apart from the history of the country, which is dealt with separately; and we turn to the other great valley of early civilisation, in Mesopotamia, to compare the resemblances and the differences between the two lands. W. M. FLINDERS PETRIE NOTABLE DATES OF ANCIENT CIVILISATION EGYPT B.C. 8000 Continuous civilisation of prehistoric age began S.D. 30 7000 Asiatic invasion S.D. 40 5800 Invasion of dynastic race 5500 Mena rules all Egypt S.D. 80 4700 Khufu builds Great Pyramid 4000 Invasion from north 3400 Middle Kingdom, twelfth dynasty 2500 Hyksos invasion, fifteenth dynasty 2250 Second Hyksos movement 1580 New Kingdom, eighteenth dynasty 1380 Tell el Amarna letters 701 Taharqa (Tirhakah) 570-26 Aahmes (Amasis) BABYLONIA B.C. Before 6000 Susa founded 5000 Ea founds Eridu and civilises the land 4700 Earliest monuments of Kings 4500 Urnina 3800 Sargon and Naramsin, Semitic rule 3300 Gudea 2280 Elamites conquer Babylonia 2129 Hammurabi 1572 Kassite dynasty 1380 Burnaburiash 690 Sennacherib 556-38 Nabonaid, fall of Babylon THE RISE OF CIVILISATION IN MESOPOTAMIA BY PROFESSOR FLINDERS PETRIE The first impression that strikes the reader in passing from the Egyptian to the Mesopotamian civilisation is the lack of that unity and conciseness which makes history in the Nile valley so intelligible, and its problems so well defined. [Sidenote: Disunion of Early Babylonia] In place of the well ordered history of Manetho, with its numbered dynasties, and totals stated throughout, there is practically nothing stated before Nabunasir in 747 B.C. The mythological extracts from Berosus, and the list of Ktesias, which cannot be identified with any known facts, give no help in arranging the outlines of the history. In place of the uniform language and writing, which develops without a break during the whole history of Egypt, there is the entire break from Sumerian to Semitic. In place of the continuous importance of Egyptian capitals, there is the change from the principalities to Babylon, and thence to Nineveh. In place of the unified kingdom of the Nile valley, through the whole written history, the greater part of the documentary period is filled with rival principalities, within thirty or forty miles of each other, the tops of whose temples must have been visible over the entire territory of their respective states. As the general scale of Egypt is so familiar to the modern reader and traveller, it will be well to compare Mesopotamia with that. Babylon was twice as far from the sea as Cairo; and from Babylon to Nineveh was the distance from Cairo to Sohag. Or in other terms, starting from the sea, Babylon was as distant as Oxyrhynchos, Nineveh in place of Thebes, and the highlands of Carchemish, Commagene, and Lake Van were the equivalent of Nubia. The old land of Shumer was just the size of the Delta, and Akkad as large as Middle Egypt. The principalities of Eridu, Lagash, Ur, Erech, and others, were as far apart as those of the Delta--Bubastis, Benha, Sais, or Sebennytos. Indeed, it seems as if this were a natural unit-size of early dominions in a fertile plain. [Sidenote: The Nile and the Euphrates] Though the relative age of the beginning of civilisation on the Nile and the Euphrates is yet an uncertain matter, still it is clear that the unification of Egypt long preceded that of Babylonia. The earliest date of the scattered Sumerian kings is about that of the fourth dynasty; the earliest Semitic dynasty--Sargon and Naramsin--was contemporary with the ninth dynasty, and the rise of the dynasties of Babylon is of the later Hyksos age of the sixteenth dynasty. [Sidenote: Sea-shore Moved 47 Miles] EUPHRATES VALLEY. The conditions of the Euphrates valley are very different from those of the Nile. On the Egyptian coast the river runs into a strong current in the Mediterranean, which sweeps away its sediment and prevents any continuous growth of the coast. But the Mesopotamian rivers reach the sea-level at the head of a deep bay, the Persian Gulf, and hence there has been a continuous formation of new land at the estuary. The Mesopotamian valley and the Persian Gulf form one long drainage valley gently sloping down to a distance about twenty miles outside Hormuz, where the valley bottom drops suddenly three miles into the floor of the Indian Ocean. The slope of this valley so far as submerged, is about 1 ft. to the mile, and it is probably even less in the Babylonian plain, where sea-shells are found as far up as Babylon. This valley has been filled, and the sea-shore pushed downward, 47 miles in 2,200 years, or 115 ft. yearly, since Spasinus Charax--now Mohammerah--was founded on the shore in the time of Alexander. The account of a sea expedition to Elam by Sennacherib is usually interpreted as showing a more rapid growth; but in the uncertainty how far he went down a channel before entering the Persian Gulf, it is not decisive. How far back the extension of land has been going on, and whether it was continuous to above Babylon, has not yet been proved. The appearance of the map much suggests that the original drainage bed ended--_i.e._, the valley was submerged--at about the nearing of the two rivers by Sippara, and that all below this is the filling up of the estuary. Should this growth have extended uniformly back so far, it would give limits to the possible ages of cities--5000 B.C. for Eridu, 8000 B.C. for the whole plain of Shumer, 10,000 B.C. for Nippur, and earlier for the site of Babylon. This would bar the southern region from being as old as Memphis, and Eridu was probably open sea when Menes laid out his capital. [Illustration: THE PLAIN OF BABYLONIA: ITS EXTENT AT DIFFERENT PERIODS IN HISTORY This map shows how the Plain of Babylonia has been extended down by silting since 10,000 B.C. The dotted lines, marked 330 B.C. and 1830 A.D., show the known positions of the coast, as it shifted by silting up. These give an approximate scale of dating for the coast-line of earlier ages, which is marked here at each thousand years. ] RANGE OF CIVILISATION. In looking for the earliest movements of people that we can trace, it seems that the Semites must have extended from Northern Arabia into Upper Mesopotamia and Assyria. In short, Semitica stretched up to the mountain ranges of Armenia and Media. But the culture was barbaric, and probably they were nomads who had no fixed centres of life or stable organisation which could resist any united movement. At this period the Persian Gulf probably extended as far as Babylon. On their eastern flank were the mountain tribes, in what is known as Parthia and Media, south of the Caspian. How remote is the beginning of civilisation in this region has been found in the last few years. On the north-east extremity of Parthia, in the far end of Hyrcania, stands a group of mounds, near the modern Askabad, not far from the celebrated Turkoman stronghold of Geok Tepe. Here are 14 ft. of town ruins with iron, 15 ft. with copper and lead, about 70 ft. of ruins with wheel-made pottery and domesticated animals, and 45 ft. of remains with only rude hand-made pottery. What ages these represent we cannot judge until the full account by Prof. Pumpelly is issued. But in any case a very long period is involved. If the accumulation is at the rate found in Palestine, 4½ ft. per century, the periods would be perhaps 1,500 years for the wheel pottery, and 1,000 years for the rough pottery, before the beginning of the age of copper. At the other side of these countries stands the great mound of Susa, with over 80 ft. of ruins. The inscriptions show that about 26 ft. of the height was accumulated between about 4500 and 500 B.C., or in about 4,000 years. Yet before that there is a depth of about 50 ft. comprising three periods. In the upper of these is elementary cuneiform writing on tablets. Below that is a period of rather rough, thick pottery, painted with chequer patterns and closely-crossed lines, of the style common in early Syria and Cyprus. And at the bottom of all is a great quantity of very fine, thin wheel-made pottery of buff tints, with decoration of thin diagonal lines, rows of ostriches, and various patterns all derived from basket-work. [Sidenote: Measuring the Depths of Time] If the scale of accumulation of the historic times were to apply here, it would reach back to 12,000 B.C.; but if the far quicker scale found in Palestine applied, it would hardly reach 6000 B.C. In any case we have here evidence of a civilisation apparently much earlier than that of Babylonia, and none of this earliest fine pottery has been found in the great plains. The highland civilisation may have begun as early, or earlier, than that of Egypt; but that of Babylonia started probably later than the North African culture on the Nile. Seeing, then, that there was a very early civilisation at Susa on the west of Media, and that further east on the limits of Parthia we meet another early centre, it is not surprising that the inhabitants of these regions united to spread down into the fertile plain which was created by the growing delta of Mesopotamia. These people belonged neither to the Semite of Arabia nor to the Aryan of Persia and India, but used an agglutinative language of entirely different structure from these others, and most akin to Turkish or Finnish. Having descended from their mountain homes, the people were known as Akkadu, probably meaning “highlanders,” though there are other open derivations. And hence the northern part of the Babylonian plain, next to the Semitic Assyrians, was the land of Akkad; while the southern part, next to the sea, was known by the native Babylonian name of Sumer, or Shumer. [Sidenote: China’s Links with Babylon] SUMERIANS. The civilisation of the Sumerians was more akin to that of the Chinese than to western types, especially in its art, its picture writing and devotion to literature, its capacity for town life, and its religious ideas. The cognate origins of the people may well account for this, and some more precise resemblances led Terrien de Lacouperie to the view that Chinese civilisation was an offshoot from the Sumerian stock in its old Parthian home. The elements of life were well developed by the Sumerians. They were great agriculturists, and wrote works on the main industry of man, much as the Carthaginians wrote standard works prized later by the Romans. They fermented the grape and corn, and had alcoholic drinks. Cattle of all kinds were raised, and prized as stock, which was fed on grass or grain or oilcake. The horse is mentioned first in Semitic times, Abut 2000 B.C. Dates and figs were the principal fruits grown; and, indeed, the date palm seems to have had a far more important place in the civilisation than it did in that of Egypt. Both wool and leather were used for clothing, as might be expected. [Sidenote: Materials for the Great Buildings] BUILDING. The main structural industry of the country was that of brickmaking and building. Immense piles of brickwork were made to support the temples, marking clearly the custom of the highlander Akkadi worshipping on the hilltops. The brick _ziggurat_, or five-stepped pyramid, at Nippur was 190 ft. by 128 ft., and about a hundred feet high. The earliest baked bricks are 8·7 in. by 5·6 in. by 2·2 in., and they were enlarged to 12 in. by 7·8 in. by 1·9 in. within the Sumerian age. Toward the close of that time large square bricks were used. Sargon made baked bricks 18 in. square and 3½ in. thick. From the time of Ur-Engur (3200 B.C.) onward the baked bricks were 11 in. or 12 in. square. Beside the baked brick used for pavements, drains, facings, and important work, the great bulk was made up of crude brick as in Egypt. For important purposes, such as store-rooms, the inside of chambers was lined with a coat of bitumen, rendering them damp-proof; and such a lining was used on tanks. Pottery is abundant in all ages, but we still need a study of the pottery such as has been made in Egypt, so that it can be used to date excavations in general. Stands for jars, framed of wood, were used as in Egypt; and also the clay sealings were of the same type in both lands. Stone vases were made to imitate pottery; and this suggests that the highlanders were only using basket-work when they descended into the plain, and therefore did not possess any types of stonework. [Illustration: THE ANCIENT BABYLONIANS AND THEIR WEAPONS OF WAR There is a fine study of weapons on a carving of Eannatum (4400 B.C.), where spears about 7 ft. long, with blade heads, are figured. Shields are shown reaching from the neck to the ankles, straight-sided, used edge to edge as a shield wall by a phalanx of soldiers. The heads of the men are covered by well-formed peaked helmets reaching down to the nape of the neck, with nose pieces. ] TOOLS AND WEAPONS. The common tools were used, such as knives and drills; and great skill was developed in seal engraving upon hard stone cylinders. Of weapons there is a fine study on a carving of Eannatum (4400 B.C.), where spears of about 7 ft. long, with blade heads, are shown; also shields reaching from the neck to the ankles, straight-sided, and used edge to edge as a shield wall by a phalanx of soldiers; while the heads are covered by well-formed peaked helmets, with nose pieces, and reaching down to the nape of the neck. Bows and arrows and daggers were also used; and stone mace-heads, of the pear shape used in Egypt, were important ceremonially, and often bear inscriptions. Woodwork was elaborated with carving, and used for bed-steads and stools, as seen in the seats of the gods figured on seals and tablets. CLOTHING. Clothing varied a good deal. A primitive custom of nudity when offering to the gods was continued down to the close of the Sumerian age, as shown on the tablet of Ur-en-lil. The kilt was worn with a fringe, not reaching the knee; or it was worn from the waist to the ankles, as by shepherds. A robe over the left shoulder reaching to the knee was used with a deep fringe all down the front edge and round the bottom. A long robe reaching to the ankles is shown on the figures of Gudea. But the most characteristic dress was that of ribbed woollen stuff, much like that of the fifth century B.C. in Greece, as on the Running Maiden. This stuff was worn as a flounced petticoat (Urnina 4500 B.C.), or in a longer form over the left shoulder and down to the ankles, as by Eannatum and Naram-Sin. A splendid flounced cape and long robe of this stuff is shown as worn by Ishtar on the Anubanini rock stele, about 3600 B.C. SCIENCE AND ART. The system of number, weight, and measure was peculiarly Babylonian. Some people have theorised about all later standards having been derived in various intricate ways from those of Babylon. But it is very unlikely that standards should not arise in different centres, and still more unlikely that the complex derivations should be formed when the whole object would be to maintain a system in common. [Sidenote: Science in Sumeria] But there is no question of the great advance of the Sumerian in these matters. The sexagesimal system, which is far more convenient for many purposes than the decimal, and which we still retain for time and for angle, was due to the Sumerian intellect, while the standards of weight, the talent, maneh, and shekel, were also from the same source. And we cannot doubt that the cubit was already in use by a people living in cities and carrying on business. The style of art was clumsy, owing to the habit of crowding together as much as possible into the space, in order to form the record. The human forms are thick and short, and detail is firmly and perseveringly repeated. It entirely lacks, in its early stages, the spontaneous truth of the early dynastic work in Egypt. At the close of the Sumerian age, under Naramsin, there is a fine bold design in groups of figures, well proportioned, and with good action, recalling curiously the spirit of late Greek work from Praxiteles to the Pergamene warriors. The stages of change cannot yet be distinguished, owing to the scarcity of the dated examples that we have. [Sidenote: Loss of History] LITERATURE AND WRITINGS. It is in literature that we know the Sumerian best. Unhappily, other branches of archæology have been neglected, and even destroyed, in the eager search for tablets, and yet more tablets. By the thousand they are found, and hurriedly removed, while the architecture, crafts, and art-history are thrown aside in the process. The hunter for tablets in Babylonia, and for papyrus in Egypt, is a heartless wrecker, without any interests beyond his own line. When so much has been sacrificed for the written record, we must glean all we can from it for the history of the civilisation, as most of the other material that might have been preserved has been sacrificed. The Sumerian language was the sole language of civilisation, until, at about 4000 B.C., the Semite began to conquer and to take part in the advance of the world. Yet the older tongue was by no means extinguished; it held its place as the official religious and literary language, like Latin in Europe. The literature of the world was in Sumerian, and only gradually did the new Semite intruders translate the older works or rise to writing a literature of their own. The Sumerian literature was for long accompanied by a Semitic translation, like Latin and Saxon gospels; and syllabaries, vocabularies, and grammatical lists were written to teach the Semite the old religious language. Legal documents were drawn up in Sumerian, and it only gradually lost its precedence from 4000 B.C. down to 1600 B.C., when it was almost extinct, being only revived as a literary curiosity in the seventh century B.C. [Sidenote: How the Semite Made His Notes] The writing was a pictorial system like the Egyptian hieroglyphics. And so long as the Sumerian used it he clung to the pictorial origin even though obscured by the lineal style of drawing. On papyrus or parchment it is easy to make curved forms, and such were adopted in drawing the signs originally. But on clay, which was the all-available material in the Babylonian plain, impressing lines is far neater than scratching them up; and the handy tool for making impressions was a slip of wood with a square end. Hence all the curves tended to become four or five-sided outlines, and all the detail became built up of little lines tapering off to one end, or “digs” with the corner of the stylus. Yet down to the close of the Sumerian age the forms of the objects can still be discerned, and they are still pictures rather than mere immaterial symbols. Mansell THE FINEST EARLY BABYLONIAN ART: TRIUMPH OF KING NARAMSIN, 3750 B.C. This work, found in Susa, is curiously free and pictorial; it is unrivalled by any early carvings, and most resembles the action and spirit of late Greek sculpture. It marks the great period of the fusion of the Sumerian and Semite. ] The Semite, however, changed all this. He learned merely the sound values of certain forms, their meaning could not appeal to him, and he built up his words out of these sounds or syllables. He found it inconvenient to write in vertical columns, which was the constant Sumerian habit, and turned his tablet sideways to his hand, so as to make his signs along a horizontal line of writing. Hence these signs became familiar to him on their sides, and as they had to him no pictorial values, the position was indifferent. Lastly, he produced a syllabary of signs written with combinations of four forms of impress, a long line wider at one end, a short line, a tall triangle, and a small equilateral triangle, written in horizontal lines; and each sign was standing on what had originally been its side. The wedge-shaped form of these lines has given rise to the name of wedge-writing, or cuneiform writing for this system. [Sidenote: The Story of a Language] The knowledge of this writing survived Greek influence for some four centuries after Alexander, only becoming extinct at the close of the first century of our era. In its long history, double that of the Roman alphabet at present, it had been used for very diverse languages. The Sumerian inventor had handed it on to the Semitic intruder, and he had passed it to the Syrian, the Mitannian, the Hittite, and the Vannic peoples. Probably it had kept its hold in its first home in Elam, where it is found in historic times, and thence it became the writing of Persia, and even of the Parthian, before it became extinct. The variety of languages and the extent of country which it covered is much like the scope of the Roman alphabet in Europe to-day. LAW AND RELIGION. In matters of law the Sumerian was well advanced. The needs of city life which he had developed necessarily required a full definition of rights and duties. The first law book was that of Ea, the god of civilisation, the Oannes of the later legends of Berosus. The decisions of judges were kept in abstract, and such case-made law served as a body of precedent to guide decisions. The position of women was on a level with that of men; in the Sumerian hymns the woman takes precedence, and one of the great Sumerian divinities was Ishhtar, who became Ashtaroth of Syria, Athtar of Arabia, and hence Hathor of Egypt. In the Semitic system the goddess is but a feeble companion of a god; but Ishtar was the great divinity of war, to whom the kings owed their triumphs, as well as the queen of love, who ruled the course of nature. _VASES_ _FORK_ _COMB_ _HARP_ _BOW AND ARROW_ _ARROWS_ _STONE_ _CLAY_ _EARLY_ _FISH_ _BIRD_ _AXE_ _VASE_ _LATE_ _EARLY_ _FISH_ _MAN_ _MONTH_ _REED_ _LATE_ THE DECAY OF PICTURE-WRITING This illustrates the decay of pictures into signs, and shows very clearly how the cuneiform writing was developed from the earlier hieroglyphics. It will be noticed that the word originally rendered by a crude drawing of the object--“fish,” for example--retains even in its final cuneiform style some resemblance to the tail of a fish. The cuneiform lettering was necessary to the Babylonians, as clay was the most abundant material in their land and could best be marked upon in lines without curves. ] The religion of the Sumerians was like that of other Turanian races. These peoples have an aversion to the idea of a personal god, to which the Semitic peoples cling. The Samoyede believes in a multitude of local spirits, the Chinese have their impersonal Heaven and the host of gnomes or earth spirits. Thus also the Sumerian thought of all objects as having a _zi_ or spirit, good or evil, which needed to be appeased by the weak or commanded by the sorcery of the strong. Shamanism was the type of religion; and books of exorcisms and magic spells were in permanent use. The importance of the principalities naturally led to their local spirits being of general importance; and hence the political changes brought Sin the moon god of Ur, or Utuki the sun god of Sippar and Larsa, or Marduk of Babylon, into a leading position, and led toward the Semitic type of deities. How far this change was due to the beginning of Semitic influence we cannot now say. Other native gods were less personal, such as Ana the sky, Enlila the earth, and Ea the sea. [Illustration: THE SUMERIAN TYPE OF BABYLONIAN The fact that the shaven type of face appears in all the monuments back to 4500 B.C. indicates that the Sumerians were shaven as they were the older of the two main races in Babylonia. ] [Illustration: THE SEMITIC TYPE OF BABYLONIAN Men with full beards are not represented on Babylonian monuments until 3750 B.C.; hence it is clear that such figures represented people of the Semitic type. This portrait is from a sculpture of King Hammurabi. ] TYPES OF RACES. The physical type of the people is shown to us by the early monuments, though we hardly yet know enough of the early history to understand them fully. Two main types stand out entirely apart, the shaven and the full-haired. And when it is seen that the shaven type is that of all the earliest human figures, dating from 4500 B.C. and extending down to even 2100 B.C., while the full-haired type is not found on men before 3750 B.C., it is clear that the shaven is the Sumerian and the bearded is the Semitic type. The remarkable point is that the gods are represented with long hair tressed up and long beards from 4400 B.C.; and as early as we can go back there is never a figure of a beardless god. The reason probably is that personal gods were of Semitic origin, their worship was borrowed, and hence their forms. If so, we must see a large Semitic influence already acting on the earliest known Sumerian art. The variations of type may perhaps lead to some further distinctions. The full, curly, square-ended beard and long hair are usual for the gods, as seen under Eannatum (4400), Urenlil (4000), Gudea (3300), and Hammurabi (2100). The same beard, but with the hair done up into a disc (as on the Tello heads and Hammurabi), is worn by the King Anubanini (3600). The long and rather pointed beard is seen on Naramsin (3750), and Hammurabi (2100). The short, square beard is seen on the god, under Eannatum (4400), and on men about Naramsin’s age [see the seal of Ubilishtar]. The shaven type has a wide face, with a large prominent aquiline nose, best seen in the head from Tello. This type is that of all the human figures on the scenes of Urnina (4500), Eannatum (4400), and Urenlil (4000); and in the figures of the Scribe Kalhi (cylinder, 3750), Gudea (stele, 3300), the heads of the same age from Tello, and the later head of beautiful work at Berlin. The general conclusions may be that the beard was worn and admired by Semites, who elaborated a very full type for the gods; and that the Semitic influx, though ruling under Naramsin at Sippara, north of Babylon, was yet subordinate at the later date of Gudea, in the Sumerian south. [Illustration: THE FAMILIAR BEARDED TYPE OF ASSYRIAN GODS AND MEN Although the full-haired faces are later in appearing on the monuments of Babylonia, all figures of gods are shown as possessed of full beards and a wealth of hair. A familiar example is here reproduced. It is supposed that the Semitic race in Assyria was the first to personalise the deities, and hence the resemblance of the images to the features of the Semites. ] SEMITIC AGE. We now turn to the later stage of the civilisation, as it flourished under the mixed race of Sumerians and Semites, partaking of the culture of the older race and the higher moral tone of the less advanced people. The Sumerians, as we have noted, had pushed down from the Median highlands into the growing plain of Babylonia, while the earlier Semites remained to the north in Assyria, and to the west in Naharaina and Syria. Sooner or later a fusion was inevitable; as we have seen already, the gods were of a Semitic type at a very early time, and gradually the union took place during three thousand years, until in the later times the product was unified in one strong civilisation which spread its strength far and wide to the Crimea, to Egypt, and to the deserts of Central Asia. BUILDING. The old skill and abilities found a wide scope in this larger frame of life. The fundamental craft of brickwork was carried on to a vast extent. Every city had its great pile of an artificial hill of bricks, built in stages to support the temple of its god high above all. Immense walls surrounded the cities; those of Babylon were some nine miles around, and are stated to have been 85 ft. high and 340 ft. thick, surrounded by a moat lined with burnt brick laid in bitumen. Not only was brickwork used on this great scale in the Babylonian plain where stone was a luxury, but the force of example was so strong that the Assyrian, in his highland home, kept up the same scale of brickbuilding as his teachers, and used brick for his palaces and temples when stone would have been much more easily available. In Babylonia, as in Egypt, the supply of material for brickmaking on a large scale is a serious question. For the great walls of cities, obviously a surrounding ditch was an advantage; but for the materials of houses, temples, and ziggurats, great pits had to be dug, or older buildings pulled down. At Nippur it was found that the later builders had torn down a long piece of the disused city wall and dug out a great pit below and around it. So in Egypt the outskirts of every village has its perilous hole where the bricks are made, which, in course of time, becomes a stagnant pond, and every ancient temple, with its fortifying wall, was built out of a large pit at its side which became the sacred lake of the temple. [Illustration: A TEMPLE PLATFORM, OR ZIGGURAT, OF BABYLONIA This restoration of the Temple of Bel at Nippur, from the designs of Hilprecht and Fisher, gives a good idea of the massive character of Assyrian architecture. The portion marked (1) consists of a stage tower with a shrine at top and a long stairway leading thereto; (2) is the temple proper; (3) house for “honey, cream and wine”; (4) “place for the delight of Bur-sin”; (5) is the inner wall and (6) the massive outer walls. ] A higher branch of building was the use of glazed bricks. In Egypt the use of glazed tiles for coating walls was boldly carried out in the earliest dynasties, before 5000 B.C.; but there was no glazing of the bricks, because in so dry a climate the Egyptian was never induced to burn his bricks. In the wet and damp of Babylonia, on the contrary, burnt bricks were usual, and all the facings and main divisions of structure were in the indissoluble material, which held together and protected the mass of crude brickwork within it. It was, however, mainly, or only, in the later times--from the ninth century onwards--that bricks glazed on the outer face were used for building. It seems that this was done not so much for utility--like our modern use of glazed bricks--as for the artistic effect of colours and designs. The grandest example of such work that is known is the façade of coloured glazed brick in relief, representing the royal archers, from Susa of the Persian age, now in Paris, restored from the fragments. Beside baked brick, pottery was used on a large scale. Great jars occur in the earliest times, and cylindrical drains of large size, sufficiently wide for a man to descend in them for repair. In later times coffins of baked pottery of the Parthian age, and glazed coffins of slipper shape, dating from the Sassanian period, are very common on most of the city ruins. Unfortunately, sufficient attention has not yet been given to the pottery of any age. [Illustration: A KING’S EMBROIDERIES This illustrates the richness of the decoration on the breast of an Assyrian king, whose complete attire is seen in the other picture on this page. ] Wood was largely used in the more wealthy ages, but it was always valuable, as large timber had to be brought from a distance. The great halls of the palaces were all roofed with timber beams, and panels of cedar lined the walls where stone was not used. Probably palm trunks and palm leaves served for ordinary roofing, as in Egypt at present. CLOTHING. Clothing became far more elaborate than in earlier ages, and the dominance of the more northern people brought a fuller dress into customary use. The Assyrian covered the whole body with a tunic down to the knees, and the upper classes wore a robe to the feet. Rich embroideries were usual among both Babylonians and Assyrians, and the splendour of Babylonian garments was spread far in other lands by trade. The cap was either cylindrical or conical, and the royal head-dress in Assyria was practically the modern tarbush, which has again been imposed on the East by the Turk. Sandals were used in Assyria, and the boot so characteristic of the Hittite was also brought in from the cold mountainous country. Women wore a long, thin robe to the feet, covered sometimes by a tunic and a cape. But Ishtar is always shown in a ribbed dress flounced from top to bottom. This is the regular women’s dress of the western Semites; and its use, like that of the beard for the male deities, points to the strong Semitic influence on the appearance and character of the divinities. [Illustration: DRESS IN ASSYRIA’S GOLDEN AGE Rich embroideries were usual among Babylonians and Assyrians, and the splendour of Babylonian garments was spread far in other lands by trade. The royal head-dress in Assyria was practically the modern tarbush, which has again been imposed on the East by the Turk. ] The armour of the Assyrian was much the same as that in the early Sumerian days. The pointed helmet became rather taller, and did not cover the back of the head. The spear, and the bow and arrow, were the main weapons as before. The old straight-sided shield was also used in Assyrian times, but was partly superseded by the round shield considerably coned. The extension of the kingdom brought in various auxiliaries, who differed from the older Babylonians. Slingers, northern horsemen clad in leather, and mountaineers with woodman’s axes, all added new branches to the army. [Sidenote: Sculpture 5,000 Years Ago] ART. The arts were carried to great perfection by the mixed population. Broadly speaking, the best work is that of the early age of Naramsin (3750 B.C.), and that of the late age of Ashur-bani-pal (640 B.C.). Though not so fine, yet probably the Hammurabi sculptures are the highest between the early and late schools. This would give intervals of 1,650 and 1,460 years between the successive waves of art, and about 1,450 years more to the glories of Baghdad, a period much like that found on the Mediterranean, though not coincident with it. The finest work of Naramsin (3750 B.C.) is his great stele from Susa, now in Paris. It is remarkably pictorial in style, agreeing in this with the pieces of a limestone stele representing rows of combatants from Tello, also in Paris. The figure of the king is lithe, active, romantic in attitude, the enemies and his soldiers are full of animation. No Oriental sculpture has had quite the same life in it; and it recalls the pictorial style of Crete and the later Greek sculpture. The art of Gudea (3300 B.C.) is more cold and formal, and has not the same fine sense of proportion; it is distinctly a period of survival and not of artistic instinct, as seen, for instance, on the limestone relief in Berlin. The age of Hammurabi (2100 B.C.) shows careful portraiture, but not the spirit of the earlier age; the work is well finished, and there was no hesitation in handling materials boldly, as on the great black stele of the laws, now in Paris. There was a fine sympathetic treatment in private sculpture, as shown in the beautiful limestone head of a Sumerian in Berlin [see page 266]. [Sidenote: Fine Later Art] The last great age was that of the Assyrian Empire. Under Ashur-nazir-pal (885) the work is fine and severe, but without much expression. Shalmaneser III. (860) troubled more about history than about art, and his principal remains are the long records of the black obelisk and the Balawat gates, which are but clumsy in the forms. Under Sennacherib (705) there is a breadth of composition, as in the siege of Lachish, which is worthily aided by a more pictorial style, while under Ashur-bani-pal (668-626) the art reaches both grace and vigour, as in the splendid natural scenes of the wild-ass hunt, in the lion hunt, and in the garden feast with the queen. [Illustration: GUDEA LED BY A GOD This shows the Babylonian art at 3300 B.C., inferior to the earlier style of Naramsin. The original is in Berlin Museum. ] MECHANICS. The mechanical arts were also greatly developed. The large size of the buildings, the great quantities of stone transported for the sculptures, and the immense size of many blocks--the bulls weigh nearly 50 tons each--all show that there was not only considerable skill, but also large ideals and directive ability. Layard found that three hundred men were wanted for drawing his cart bearing the great bull; and the sledge used by the Assyrians for the transport must have needed as many, or more. Long levers are represented as having been used in a very effective manner; but the placing of such great blocks exactly in the right position required far more ability than the mere transport. The forms of tools were much in advance of those used by the Egyptians. As far back as Naramsin, the copper axes were all well hafted, generally with rings raised round the edges of the haft hole to strengthen the band and prevent it splitting. [Illustration: AN ARTISTIC TRIUMPH OF ASSYRIAN SCULPTURE Under Ashur-bani-pal (668-636 B.C.) Assyrian art reached both grace and vigour, as is manifest in the splendid natural scene of the wild-ass hunt, which is here reproduced from the original in the British Museum. ] [Sidenote: Modern Tools of Ancient Workers] The forms of the iron tools are also excellent; and iron seems to have been common in Assyria at an earlier date than in any other country, probably from the tenth or twelfth century B.C. Certainly the set of Assyrian tools left at Thebes by an armourer of Esarhaddon in 670 B.C., show that the principles, and even the exact forms, of modern tools had already been reached. The chisels and rasp have not been improved since; the saw is the same as the modern Oriental pull-saw, but the teeth have not an alternate set; the centre-bits and files anticipate our forms, but have not reached the complete stage. The material of most of the edge tools is steel, showing that the hardening was then understood. The cutting of seals in hard stones was an early art, but it was well maintained, and some of the most beautiful specimens are the chalcedony cylinders such as that of Sennacherib in London. The engraving of the inscriptions also shows that cutting in hard stones was freely done on a great scale; but the writing, being entirely in straight lines, was much easier to engrave than the figures of natural objects of the Egyptian signs. Probably emery powder or copper was the means used, as in Egypt. [Sidenote: The Books of Babylonia] The use of an official stamp of guarantee on uniform pieces of silver was adopted by the time of Nebuchadnezzar, but as this is two centuries later than Greek coinage it was probably copied from that. In one respect the Mesopotamian never equalled the Egyptian. The Memphite school of work had attained to a mechanical accuracy which we can scarcely gauge; their errors on large pieces of work were only a matter of thousandths of an inch. But the Mesopotamian never did a piece of passably square or regular stonework; the inequalities and skew angles are glaring, even in highly elaborated works of art. The sense of accuracy was quite untrained, and neither Semite nor Sumerian show any ability in this line. Egypt, on the contrary, started with a prehistoric race which excelled in exquisitely true handwork and dexterous flint flaking, and with the artistic sense of the dynastic people added, the combination was one of the highest that the world has seen. LITERATURE. To give any adequate idea of the literature of Babylonia is far beyond our scope, and only the main classes of it can be named in this outline. These were: 1. Theology and Omens. 2. History. 3. Despatches and Correspondence. 4. Language and Translation. 5. Mathematics. 6. Astronomy. 7. Geography and Natural History. 8. Medicine. [Illustration: HOW THE GREAT STATUES WERE MOVED: A CONTEMPORARY RECORD FROM THE MONUMENTS OF NINEVEH The large size of the buildings of Assyria, the great quantities of stone transported for the sculptures, and the immense size of many blocks--the bulls weighing nearly 50 tons each--all show that there was not only considerable skill, but also large ideals and directive ability. Layard found that 300 men were wanted for drawing his cart bearing the great bull; and the sledge used by the Assyrians for the transport must have needed as many or more. The tools used were much in advance of those of the Egyptians. ] The striking omission is that of literature in the form of tales or poetry of actual life; there seems, amid all the myriads of tablets, to be nothing similar to the tales of the various periods of Egypt. We look in vain for the tales of the magicians, the romances of adventure, of love, or of history, which restore to us the living view of Egyptian thought. The Babylonian was severely commercial or scientific, and his poetical ideas were only developed in his theology; he seems to have had no play of fancy or taste for the excitement of story-telling. Similarly in the Middle Ages the “Thousand and One Nights,” though often referring to Baghdad, are yet tales of entirely Egyptian source and idea. [Sidenote: Wonderful Training of Babylonians] But for his own purposes the Babylonian was well educated from a literary point of view, and, considering the complexity of his writing, he was probably better trained than any modern people except the Chinese. The hundreds of signs which he had to remember had long lost their pictorial significance, and needed an attentive memory and long training; yet not only in public documents, but also in private letters, mistakes are but rarely found. Classification of the signs, classified lists of words of Sumerian and Semitic, grammatical works, and reading books were the apparatus used. Even the peasantry and sometimes the slaves learned to write, and there was hardly more need of a professional scribe than there is in England to-day. But this general education belonged to the Sumerian stock, and was much diminished where the Semite was in the majority, so that in Assyria only the upper classes could write, and nail-marks of contracting parties are common. The feeling for literature kept the names of great writers in remembrance, and the authors of the main religious pieces, such as the Epic of Gilgames, are still known. The Egyptian, on the other hand, has not preserved the name of a single author; even Pentaur was probably only a scribe. The honouring of literature led to the Assyrian kings amassing great libraries, and to the princes becoming librarians and secretaries. The copying of ancient tablets for the new libraries was a large business, carefully planned; and the scribe was required to exactly state where his original was defective and what uncertainties existed in the reading. Even private persons sought to obtain favour by presenting copies of works to the temple libraries. [Sidenote: Shall We Find an Assyrian State History?] Of the classes of writings, the religious works are noticed later; the historical writings are mainly Assyrian, recording the constant wars with other lands, and the tribute and booty brought from them. That there was a complete State history is shown by the ready allusions to the time since certain events had happened. Ashur-bani-pal recounts 1,635 years since the Elamite king had carried off an image. Nabonidus searched for and found the tablet of Naramsin, which he says had not been seen for 3,200 years; he recites that there were 800 years from his time to Shagarakti-buriash, and 700 years from Burnaburiash to Hammurabi. These references show that we may hope to recover a complete State history from Assyria, as we may hope yet for a complete historical papyrus from Egypt. The despatches and correspondence give full light on detail of politics and affairs, showing the conditions of various countries; and where a sufficient number have been preserved together it is possible to build up a continuous history of a period, as in the case of the Tellal-Amarna letters. The yearly annals of a reign belong more to the historical division, and such records of Sennacherib, Ashur-bani-pal, and others are of the highest value. The private letters give a full view of the current life; and the business documents, especially receipts, are the commonest of all records, showing the trade, the law, and the business of the country in all its fulness. [Sidenote: Beginning of Astronomy] The tablets dealing with the Sumerian and Semitic languages together, and the translations from one to the other, we have noted already. The mathematical tablets are multiplication tables, lists of multiples of measures, tables of squares and cubes, and plans with measurements along the sides, which show the practical use of the science. The astronomical records were already tabulated in the time of the early Semitic Empire, Sargon having compiled for his library a work in seventy-two books, the title of which is rendered “The Observations of Bel.” The purpose of this was astrological, like the great mass of short tablets reporting observations of a later date. But the inquiries involved a considerable familiarity with astronomical movements, and a mass of records which became of great value to the student. The astronomical tablets of the Seleucid period are of special value, as they often contain valuable historical matter. [Illustration: A KING’S LETTER OF 1400 B.C. A clay tablet letter from Tushratta, King of Mitani, to Amenophis III., King of Egypt, announcing the despatch of valuable gifts and begging Amenophis to send him a large quantity of gold as payment for expenses incurred by his grandfather in sending gifts to the King of Egypt, and also as a gift in return for his daughter, a princess of Mitani, whom Amenophis had married. ] LAW. In the domain of law the Babylonian had early formulated a code from the actual working of decisions. Case-made law was his basis, as in most countries, and abstracts of important cases were carefully preserved as precedents. No torture was used upon witnesses, and ample investigation of the right of a case seems to have been usual, with full cross-examination. High penalties were stipulated for the infringement of sales or contracts. The status of women was equal to that of men in the Sumerian, but became inferior in the Semitic law. Slavery was rather an assignation of labour than a control of the person, as a slave family could not be separated. Slaves could hold property, own other slaves, give witness, and were sometimes well educated. The family union was strong, as inherited land could not be sold without assent of relatives, and boys and girls alike inherited intestate property. The detail of the laws form a long study, but we may here note the main sections of the great code of Hammurabi, showing the scope of the laws, and stating the number of enactments. Witchcraft 2 Legal falsehood 3 Theft 3 Loss 5 Child and slave stealing 7 Robbery 5 Royal messengers and officers 16 Agriculture 24 Accounts 8 Licensed traders 6 Marriage property 19 Women 32 Votaries property 7 Adoption 10 Assault 20 Doctors 13 Builders 6 Shipping 7 Cattle 12 Hire 25, and Slaves 5 Distraint & deposit 13 Thus the whole scope of an agricultural and commercial community was well safeguarded, and little doubt left as to general principles and penalties. All this must have been the product of innumerable cases and difficulties for two or three thousand years, before such a complete code was set up. HISTORY IN MYTHOLOGY. The religion has usually occupied a large part of the attention and interest given to Mesopotamia; it is comparatively well known owing to the quantity of documents and representations. Here we need only mention such points as bear on the general civilisation. We have already noticed how the purely Sumerian Shamanism, or belief in the spirit of every object, which needed to be appeased, had been tinctured by the worship of personal deities of the Semitic neighbours, and how this influence was shown by borrowing the Semitic beard for the gods and flounced robe for the goddesses, and occasionally for the gods. Thus the Semite was the missionary of theism as against animism. [Illustration: SIR A. H. LAYARD’S EXCAVATORS LOWERING ONE OF THE GREAT WINGED BULLS FOUND IN NINEVEH These bulls weighed fifty tons each. Layard found that three hundred men were necessary to pull the cart on which the bulls were placed. ] [Illustration: A CAMP SCENE IN THE DAYS OF NINEVEH’S POWER The interior of a castle, indicated by a kind of ground-plan with towers and battlements, is divided into four compartments. In each is a group of figures, either engaged in domestic occupations or in preparations for a religious ceremony. The pavilion is supported by columns, probably of painted wood, and the canopy is adorned with a fringe of alternate flowers and buds, like the usual Egyptian border. Beneath the canopy is a groom cleaning a horse with a curry-comb. A eunuch at the entrance is receiving four prisoners. Above are two mummers dressed in the skins of lions, while a figure with a staff appears to be the keeper of these monsters. ] On the other hand, the civilisation of Babylonia is expressly stated to have been given by Ea, or Oannes, who rose from the sea of the Persian Gulf; he passed the day among men, and taught letters and sciences and arts--the building of cities and temples, and the use of laws and geometry. Also he showed the uses of seeds and fruits, and softened and humanised the people, who had lived in a lawless manner like wild beasts. This full ascription of civilisation to sea immigrants shows that it cannot be set down as an indigenous growth, or as due to the Sumerian, or still less to the Semite. The date of this movement is roughly indicated by Ea, belonging to the city of Eridu; and 5000 B.C. is the earliest date at which we can suppose the ground of that city to have been dry land. Such must be taken as the extreme limit of the early civilisation, and what we find of the early kings of about 4700 B.C. is the first efficient rise of monumental history in the land. All this is parallel to the early civilisation in Egypt. That also came in apparently from the Red Sea at about 5800 B.C., as the civilising movement which changed the prehistoric age to the dynastic. And it came only a few centuries earlier than the mission of Ea. It may be possible that there is one common source of a seafaring people for both civilisations, and, if so, we might look to Hadhramot as being in the most likely common centre. At least, it is always convenient to explain the unknown by the unknown. The nature gods of Apsu and Tiamat, the ocean and the chaos, described in the first tablet of the Creation series, belong to the primitive Sumerian. “The waters of these mingled in union, and no fields were embanked, no islands were seen; when the gods had not come forth, not one; when they neither had being nor destinies.” And afterward “Evil they plotted against the great gods.” After an attempt of Anshar (perhaps the same as the Egyptian Anher, the sky god) to subdue Tiamat (tablet 2), Marduk, the sun god, gains the victory; and in tablets 3 and 4, the supremacy of Marduk is finally confirmed by all the gods. In this we seem to have the echoes of a tribal history as in the Egyptian theology. The Shamanistic worship of a confused host of warring and malignant spirits, is at last subdued by the worshippers of personal gods under Semitic influence, and of these the people of the sun god take in the end the leading place. All of these changes were, however, long before the political domination of the Semite, which began about 3800 B.C., with Sargon. [Illustration: A CHASE IN THE DESERT, RECORDED ON THE MONUMENTS OF NINEVEH The series of which this bas-relief formed a part appears to have recorded the conquest by the Assyrians of an Arab tribe or nation who made use of the camel in war as a beast of burden. This sculpture belongs to a later period than the bas-relief from the North-West Palace at Nineveh reproduced below. ] [Illustration: ROYAL SPORT IN THE DAYS OF ANCIENT NINEVEH This bas-relief probably formed part of a subject representing the King of Nineveh in his chariot hunting the wild bull. The warrior rides on one horse and leads a second, richly caparisoned, for the use of the monarch. Numerous small marks on the body of the animal probably denote long and shaggy hair. ] [Illustration: BABYLON: THE WONDER CITY OF ANCIENT CIVILISATION AT THE HEIGHT OF ITS POWER] [Illustration: NIMRUD: ALL THAT IS LEFT OF ONE OF THE WONDER CITIES OF ANCIENT BABYLONIA A view of Birs Nimrud, the traditional site of the Tower of Babel. On the plain below are the silent ruins of the ancient city, once filled with a teeming population. ] [Illustration: A VIEW OF HILLAH, THE MODERN BABYLON] We have now reviewed the questions of the rise of civilisation, as apart from the ordinary history of the countries, which is dealt with in its proper place in this work. Though it is difficult, and rather misleading, to look at civilisation and the political history apart, yet, so much has come to light in recent years to clear our view of the origins of culture that we may be allowed to focus our attention on that view of man, apart from his better known history. We seem at last to have reached back to a definite beginning of arts and capacities on both the Nile and the Euphrates, and to have touched a condition of things that seems to point in both lands to some external source of a yet pre-existing culture, which yet has to be traced. I am happy to add that one of our greatest Babylonian scholars, Dr. Pinches, concurs in the view of his subject which is here presented. W. M. FLINDERS PETRIE [Illustration: THE EXILES IN BABYLON “By the rivers of Babylon there we sat down; yea, we wept.” From the painting by Bendemann. ] [Illustration: THE RISE OF CIVILISATION IN EUROPE By DAVID GEORGE HOGARTH, M.A.] [Sidenote: “Out of the East came Light”.] “Out of the East came Light” has been the text on which all great historians of civilisation have preached, from the authors of the Mosaic literature down through Greek and Roman times to our own. Hebrew writers have looked back to Mesopotamia; Greek writers to Egypt; Roman writers to Greece; writers of Western and Northern Europe and the New World to Rome, Greece, and Palestine. Their belief is justified in so far as it is based on two great facts. Man first found in the warm, alluvial valleys of Southern Asia and North-Eastern Africa the conditions of climate and soil most favourable to his upward progress from the savage state; and from these regions, so soon as with increase of numbers he was moved to migrate, his steps were turned by the geographical conditions surrounding his early homes, in a general way, westward. He knew not yet how to cross broad seas; deserts, sandy steppes, high mountains and tropical forests and swamps were equally deterrent. The Polar ice-sheet, which had extended in Pleistocene times to the Caspian, Black Sea, and Danube basins, and still lay, in the dawn of human civilisation, far south of its present limits, probably rendered, with its wide fringe of impassable moraine, forest, and tundra country, all the lands included in the present Empire of Russia singularly inhospitable. Whoso looks at the map of the Western Hemisphere, bearing these facts in mind, will see at once that the line of least resistance, and, indeed, the only possible line, led the men of the great sub-tropic river valleys towards and along the Mediterranean coasts. [Sidenote: Civilisation from Without] In so far, therefore, as European civilisation is a state of things due to influences from without, it is due to the East; but that is very far from the whole explanation of its origin. The impulse to rise above savagery has not always--not, indeed, usually--come to peoples from without; and probably in primitive time, when communications were slow and difficult to a degree which we can hardly realise, the origin of local culture was seldom or never to be accounted for thus. In modern days there have been obvious instances to the contrary; but even now it remains to be seen how far civilisations originated among absolutely barbarous peoples by contact with higher races are real and living growths. Examples of the modification and possible elevation of ancient indigenous societies by incoming aliens, such as have been seen in Mexico or Peru, India or Japan, Egypt or Barbary, are not in point; for in these cases local civilisations certainly existed long before the foreign influence. We must look to the history of the relations of white and negro, or other savage, races in the homes of the latter, and the results of such inquiries are far from conclusive. Does civilisation so originated grow and thrive? Do even the races thus civilised themselves any longer thrive and grow? Our antipodean colonies, and the story of the native races of North America, if there were no other instances, would not admit a categorical affirmative. Nay, rather, the evidence so far available tends to discount the permanence of transferred civilisation, and to throw doubt on the continued vitality of races so civilised. [Sidenote: The Escape from Savagery] [Sidenote: Conditions Essential for Civilisation] It is necessary to raise this question at the outset of the present essay because it has been too often assumed, both implicitly and explicitly, by historians of our civilisation, that all the cultural development of Central, Western, and Northern Europe has been due to alien influence, exerted from the south and south-east, and mainly by the agency of the Greek, Græco-Roman, and Græco-Romano-Semitic (the Christian) systems. Maine’s famous dictum that “Nothing moves in the world which is not Greek in origin” has long dominated our thoughts. Yet that magnificent generalisation is contrary not only to inherent probability, but to known fact. Escape from the savage state, as Buckle showed, depends in the first place on the existence of such conditions of geographical environment as favour the accumulation of wealth and the development of a leisured class--that is, such as conduce to the production of a good deal more than the minimum necessary for life. It can, therefore, have taken place wherever man found comparatively genial climate and remunerative soil, and, in process of time, made for himself, by clearing forests or draining swamps, an arable area which would feed him and his more abundantly than was absolutely necessary. Where these conditions were presumably present it is unreasonable to suppose that the beginnings of civilisation were deferred age after age, until late in time some stimulus chanced to be imparted by an alien race or races which had, after all, advanced towards their own civilisation, albeit earlier, through the operation of similar conditions elsewhere. In the European areas inhabited by the Celtic and Germanic peoples, for instance, long before we have the slightest reason to believe that these can have come into intimate relation with the civilisations of the South and East, both climate and soil were unquestionably favourable, and local civilisations cannot but have been originated independently. As has been well said, “Man everywhere has the same humble beginnings”; and, up to a certain point, which is found to be, in fact, far later than the inception of some kind of culture, he will satisfy his primitive needs and desires in very much the same ways. [Sidenote: Spontaneous Civilisation in Europe] Under certain conditions, known to have arisen independently in many different regions of the earth, articles of luxury and art, irrefragable witnesses to incipient civilisation, begin to be produced spontaneously. To what remote periods have not cave deposits thrown back the history of artistic effort in the valleys of Gaul? And what credit, in reason, can be given to Greece, or even to Rome, for the elaborate social order of the Teutonic tribes, which was of ancient standing when first the Romans penetrated beyond the Danube and Rhine? So well rooted in the soil, so potent and so widely diffused were the Teutonic and Celtic social systems, that in the history of our actual civilisation they are factors as worthy of consideration as the influences of Rome, Greece, or Palestine. If Græco-Roman Christianity came greatly to modify them in the end, they had, perhaps, ere that, modified Christianity itself hardly less; and the social superiority of the northern and western adherents of the now dominant religion is probably as much due to character and habits developed before ever its creed was formulated, as the dominance of the Turkish peoples in the Islamic system is undoubtedly due to social characteristics evolved in the oases and steppe-lands of Central Asia far back in the “Times of Ignorance.” Let it, therefore, be understood that in the following pages it is not necessarily the whole origin of European civilisation that is being set forth, but the modification and heightening of probably pre-existent European culture by the first influences of the Nearer East which can be supposed to have reached it. Of these influences the effect is to some extent a matter of inference only. We cannot always, or, indeed, often, point with any assurance to actual results of their action. In great part we must still be content with little more than a demonstration that directly along certain lines of communication, or indirectly through certain intermediaries, the civilisations of the South could, or did, come into relation with European areas at an early age. [Sidenote: The Two Great Sea Routes] The sea routes which were most likely to be used in ruder ages by Levantine mariners, after leaving the Nile estuaries or the Syrian ports--which, as a matter of fact, are known to have been most used--are: that which followed the littoral of Asia Minor to Rhodes, whence it bifurcated, to Crete on the one hand, and to the Ægean isles and coasts on the other; or that striking across the narrow strait to Cyprus, and thence by way of Rhodes, or directly, to Crete. In connection with both these routes, the importance of Crete and Rhodes, and especially the former, must be obvious. Thence the Cyrenean and Carthaginian projections of Africa were reached with greater ease than by way of the littoral to west of Egypt, which, for some hundreds of miles, is desert, reef-girt, almost harbourless, and pitilessly vexed by an on-shore wind. From Carthage, Sicily and the Italian peninsula were readily accessible, or the Gibraltar strait and the Iberian shores could be made after coasting a littoral much kinder to navigation than that between Egypt and the western bight of the Syrtis. [Illustration: THE GREAT SEA ROUTES OF ANCIENT CIVILISATION Along the routes marked in this map lay the course of Ægean and Phœnician civilisation. The importance of Crete and Rhodes in the spreading of civilisation is clearly seen; they may be called the “half-way houses” between Mesopotamian culture, with its seat in the valley of the Euphrates, and Egyptian culture, in the valley of the Nile. ] [Sidenote: The Two Great Land Routes] The land routes in chief were also two. The Nile valley, closed by desert on the western side, had comparatively easy access to the great natural road which, leading northwards through Syria, passes at first along the Palestinian littoral, and then through the central cleft between the Lebanons to the Orontes valley. Mesopotamian traders, following up the Euphrates till they had left the desert part of its course behind them, fell into this same road in the region of Aleppo and Antioch. Thence by the easy passes which turn the southern end of Mount Amanus, the combined caravans reached Tarsus, penetrated Taurus by the gap of the Cilician Gates, and found themselves on the plateau of Asia Minor with a choice of easy routes leading either to the rich western littoral, or the north-western straits, and from any and every point offering safe passage to South-eastern Europe. This was the only land route for Egyptian civilisation. But the Mesopotamian had an alternative one, leading by way of the upper Tigris valley to the north of Taurus and the Cappadocian plateau, whence it descended the Sangarius and debouched, like the first route, on either the north-western or the western coast of Anatolia. [Sidenote: The Royal Road up into Asia] In speaking of such land routes, we do not, of course, mean to imply the existence of any made road, nor even of a single track. When most definite, they probably resembled the Syrian Pilgrim Way--a skein of separate paths now spreading widely, now running into and across one another; and doubtless the early tracks diverged far more than this, and making great elbows, followed now one valley, now another, to meet again only after many days. One of the great lines from Mesopotamia to the western Anatolian coast, that described last in our enumeration, came to be defined more strictly than the rest, perhaps by the Kings of Nineveh and their “Hittite” rivals and allies in Cappadocia, and was known in the Persian era to the Greeks as the Royal Road “of all who go up into Asia.” But at the much earlier time with which we are most concerned, the influences of the East did not rush westward torrent-wise in one bed, but soaked slowly, finding a way now here, now there, in one general westward direction, and sending offshoots far out to right and left of the main streams. [Illustration: LAND ROUTES OF ANCIENT CIVILISATION The great natural roads along which lay the path of Egyptian and Mesopotamian culture are marked in white lines on this map. A study of the map, with a careful reading of this chapter, will make clear the way in which civilisation spread in Egypt and Babylon. It is along these lines that there are found evidences of the influence exerted upon Europe by the civilisation of the valley of the Nile and the Euphrates. ] [Sidenote: Half-way Houses of Civilisation] It has been said that there is evidence of the routes just indicated having been, in fact, those most used. It is upon these lines, and no others, that we find certain remarkable focuses of early culture disposed as half-way houses between the Mesopotamian and Egyptian civilisations on the one hand, and continental Europe on the other. These are, in relation to the sea routes, first, the prehistoric Ægean civilisation, focused from the first in Crete, but extended to all isles and peninsulas of South-eastern Europe from Cyprus to Sardinia and Spain; and, secondly, the Phœnician, originated on the Syrian coast, but focused also at a later time at a second point much farther west--namely, on that Carthaginian projection, whence lay easy sea-ways to Sicily and Italy and all the western seas. Hard by the Egyptian land route lay this same Phœnician society; while all about its point of junction with the Euphrates road, on both its continuations north-westward, and on the northern road from Mesopotamia so soon as this had passed Euphrates, was established the singular but as yet little understood civilisation which we call Hittite. How early we may assume the latter’s existence in North Syria is still doubtful; but since the discoveries of Winckler at Boghaz Keui, there is little question that it was focused in prehistoric time in Northern Cappadocia, whence its influence seems to have radiated southward to the confines of Palestine, and westward to Lydia and almost the shore of the Ægean Sea. It is to this North Cappadocian region that the Tigris route from Assyria and Babylonia, which was afterwards the Persian “Royal Road,” tended. Among these civilisations the most important for our present purpose is the Ægean, because its geographical area touched at some point all the westward roads, whether by sea or land; and, moreover, because it is the one which actual evidence both dates from the remotest antiquity and most clearly proves to have been operative on Europe, especially on the most expansive of its early cultures, the Hellenic. The recent exploration of Crete, due in the main to Messrs. Arthur Evans and Federico Halbherr, has enhanced enormously the significance of the civilisation revealed to the modern world at Hissarlik and Mycenæ by the faith and fervour of Henry Schliemann. [Sidenote: Far-back Evidences of Culture] We are now assured of certain facts of much moment to our inquiry. Firstly, that this civilisation was developed originally from its rudest beginnings within the Ægean area itself. This is proved by evidence of the uninterrupted evolution of fabrics and decoration, especially in ceramic ware, produced at Cnossus from the dawn of the historic Hellenic period right back to Neolithic time. At various points in this long retrocession we can place the Cnossian culture in synchronic relation with the Egyptian by the presence both of Egyptian objects in the Ægean strata, and Ægean in the Egyptian. These points correspond with the highest developments respectively of the New, Middle, and Old Pharaonic Empires--moments at which we should naturally expect to find evidence of international communication. The earliest point indicated by these synchronisms lies possibly as far back as the First Dynasty, if certain vases, exported apparently from the Ægean as vehicles for colouring matter, and found by Dr. Petrie at Abydos, are accepted as of the remote date to which their discoverer attributed them; but in any case the contemporaneity of some part of the Old Empire period with the Ægean civilisation is assured, and that, moreover, when the latter was already far advanced beyond its rudest origins, as represented by the contents of the thick strata of yellow clay which underlie the earliest structures at Cnossus. [Sidenote: The Ægean Civilisation is Native] Thus is the indigenous origin of Ægean civilisation assured. So also is the independence of its after development. The typical Cretan pottery, known as the “Kamares” style and lineally descended from Neolithic ware, which attained, about the acme of the Pharaonic Middle Empire a perfection both of fabric and ornament worthy of the highest ceramic products of any age, remained absolutely distinct. The same independence characterises a later ceramic product of the Ægean, a glazed ware with monochrome decoration, which went into Egypt abundantly under the Eighteenth Dynasty, and especially when Amenhotep IV., “Khuenaten,” was reigning in his new capital at Tell-el-Amarna. Nor is Ægean art distinctive only in its humbler products. The frescoes, the plaster reliefs, the chased work in precious metals, the ivory carvings, and the gem intaglios of the Ægean area, of which Sir Charles Newton said thirty years ago that they were not to be confounded with products of any other glyptic art, show the development and retention of an individual naturalistic style--a style which reacted on the fresco paintings of Egypt itself under Khuenaten. Finally, to clinch the proof of its independence with the strongest possible argument, the Ægean civilisation, as soon as it became articulate, evolved for itself, in Crete at any rate, a system of writing, displayed to us on some thousands of surviving clay documents, which was purely its own, and cannot be interpreted by comparison with any other known script. [Illustration: THESEION TEMPLE, ATHENS: DORIC ORDER OF ARCHITECTURE The perfection of the Hellenic style, derived from Ægean architecture. 5th century B.C. ] [Illustration: TEMPLE OF WINGLESS VICTORY: IONIC ORDER The perfection of the second Hellenic style, refined from the Doric, probably in the first place by Asiatic Greeks. Fifth century B.C. ] [Sidenote: The Contact of Early Civilisations] Secondly, it is now known that this civilisation, of remote indigenous origin and independent development, reached a very high point of achievement in many respects which afford the best-known tests of culture--namely, in its artistic products, extant examples of which offer ample evidence of wonderfully close study of natural forms, of mastery of decorative principles and their execution, and of a sort of idealistic quality, which has been rightly called “a premonition of the later Hellenic”; also, in architectural construction and the organisation of domestic comfort, as displayed in the palaces at Cnossus and Phæstus, with their superposed stories, their broad stairways of many flights, their rich ornament, their arrangements for admitting air and light, and their astonishing systems of sanitation and drainage. The written documents found, though still undeciphered, plainly attest an advanced knowledge of account-keeping and correspondence. The frescoes and gem scenes, as well as many surviving objects of luxury, attest the existence of a leisured and pleasure-loving class; and, lastly, the tribute-tallies of Cnossus support the inference which is legitimately drawn from the uniformity of certain material objects all over the Ægean area at certain periods--notably that contemporaneous with the earlier part of the Eighteenth Egyptian Dynasty--and also from the wide range of certain place-names, that there was an extensive imperial organisation. The centre of this empire, as well as the original focus of the civilisation, was almost beyond question in Crete. The prejudice in favour of other focuses raised by the priority of Ægean discoveries elsewhere, especially those made in the Argolid, has been greatly weakened by demonstration of the superior catholicity and quality of Cretan culture, and by recognition of the failure of Mycenæ to offer evidence of anything like the same antiquity. And no more need be said here to counteract it than that, if Buckle’s statement of the climatic and geographical conditions necessary to the first development and upward progress of culture be sound, those conditions were never present in plenitude anywhere in the Ægean area except in Crete. There are found in the most conspicuous degree the combination of these geographical features--large tracts of fertile and deep lowland soil; mountains so situated as to cause abundant precipitation, and so high as to store snow against the early summer; absence of both swamps and desert areas; and a climate not prone to extremes. [Sidenote: What Crete has Taught us] Like all other high civilisations the Ægean both borrowed and lent. Since its debts could be contracted only with contemporary cultures as high as its own, they were owed mainly to Egypt and Babylonia, while its loans went out chiefly to lower civilisations further removed than itself from the eastern centres, those, namely, of the European continent. As regards Egypt, something has been said already of its intercourse with the Ægean in all ages of the latter’s prehistoric period. The evidence of that intercourse, known even before the exploration of Crete, was fairly abundant, though limited almost entirely to later ages of Ægean culture, often called particularly “Mycenæan.” The “pre-Cretan” case was set forth very concisely in a paper read before the Royal Society of Literature in 1897 by Professor Flinders Petrie, who enumerated the objects of Egyptian fabric or style found on Ægean sites, notably at Mycenæ, and in Cyprus and Rhodes; and of objects of Ægean style or fabric found in Egypt, notably at Thebes, Memphis and Tell-el-Amarna and in the Fayum. One word of warning only may be added--that the occurrence of such imported objects, especially if they be of the amulet class, on a site of a certain date does not necessarily imply exact contemporaneity with the period at which the objects were actually produced; for they may well have been carried hither and thither in the stream of trade for some time ere coming to rest, and been long preserved afterwards. Some of the Cypriote and Rhodian tombs, for example, in which scarabs and other Egyptian objects of the Eighteenth Pharaonic Dynasty have been found, are probably considerably later than that dynasty. Crete has largely reinforced this evidence, not only by throwing it back to a much earlier time than that of the Eighteenth Dynasty, but by proving that in its later periods Ægean art had come to be considerably modified, both in forms and in motives and treatment of decoration, by the art of Egypt. We have then to do, not merely with mutually imported objects, but, much more than was previously understood, with the mutual action of influences--the strongest possible proof of close intercourse. On the Ægean side, our sole concern at present, are now found scenes represented in fresco-painting or metal-work--for example, the mural scene with a river and palms at Cnossus, and the well-known cat-hunting scene inlaid on a Mycenæan poniard--and also decorative motives which are of obvious Egyptian parentage. Other motives proclaim their alien origin by more or less mistaken treatment. The best instance in point is the use made of the lotus motive in Greece and the isles, where the flower was never domiciled. [Illustration: PALLAS ATHENA, THE MAIDEN GODDESS OF ATHENS One of the chief glories of the art of ancient Greece left to the modern world. Athena was the goddess and protectress of Athens, and her statue stood at the height of the Acropolis, dominating the city. ] [Illustration: THE SUPREME MONUMENT OF ANCIENT GREECE LEFT TO THE MODERN WORLD The Venus of Milo, one of the noblest examples of Greek art, and one of the most famous statues extant. Found at Milo, in Crete, about 100 B.C., and now in the Louvre, Paris. ] [Sidenote: Influence of Egypt and Mesopotamia] For influences of the Mesopotamian civilisation we have to look in the main to the early civilisations of Syria and Asia Minor; but evidence is not wholly wanting on Ægean sites. A Babylonian cylinder came to light at Cnossus; the fashion of dress, especially female, as shown in Ægean frescoes and gems, is very like the Babylonian, from whatever primitive garments it had been developed; and in other respects also the intaglio class of Ægean art products shows at least as much Mesopotamian as Egyptian influence. It has borrowed the decoration of both cylinders and scarabs; but it proves its essential independence all the time by never adopting the forms of either of those characteristic alien vehicles of glyptic art. [Sidenote: Religious Ideas of Early Times] Lastly, in the most important of all aspects of early civilisation--the religious--we now know that the Ægean approximated very closely to the old civilisations to south and east of it. The main idea of its cult was that which seems to have been the oldest and the most dominant in such cults--namely, the worship of the reproductive force of Nature. This idea was embodied, as soon as divinities were imagined in human shape, in feminine form, the desired relation of divinity to humanity being expressed by the addition of a son-consort. How far other features of this cult, common to the south-eastern lands--such as the descent of the son to the human race, his periodical death at the hands of the latter, and his joyful resurrection--were present, we do not yet know. It would probably be false to ascribe the presence of this cult idea in Ægean civilisation to any foreign influence, for it seems to be a necessary expression of the religious sense of many peoples, and is as likely to have been as indigenous in the case of Rhea and Zeus (to give the Divine pair their possible Ægean names) as in those of Isis and Osiris, or Ashtaroth and Tammuz-Adon. But we may note first that here was a vital bond of affinity between the Ægean folk and their mainland neighbours on east and south, and second, that long before historic Hellenic times, the former had arrived at that essential condition of progressive civilisation, an anthropomorphic conception of divinity. [Sidenote: The Greek Debt to Ægean Civilisation] Enough has now been said to show that Ægean civilisation was both a broad channel through which influences of Asiatic and Egyptian culture could and did flow, and also in itself of such importance as to be likely to exert influence on nascent civilisation in Europe. To see whether it did so, we look first to the culture which succeeded it in its own area, the Hellenic culture of the historic age, about whose action, exerted indirectly on all subsequent civilisation, there is no possible doubt. And at the outset stress must be laid on the fact that we are dealing, in respect of the two civilisations in question, with one and the same geographical area. There is here no question of alien influences dependent on short or long communications by sea or land. The Hellenic race, if indeed to be distinguished from all elements in the earlier Ægean, came into the very domain of the latter, and experienced by actual contact the full force of the pre-existent culture. This being so, the probability of heavy debts having been contracted by the later culture to the earlier is enormous; and it becomes all but certainty when the few facts which we know about the early history of the Hellenic peoples proper come to be considered in the light of ascertained general laws governing the relations of intermingled races. [Sidenote: Emerging of Historic Hellenism] It is clear that the Hellenic tradition of a great descent of peoples from the north into mainland Greece and the western isles, about 1000 B.C., enshrines substantial fact. These peoples, possessed of iron weapons, were superior to the Ægean folk in war, but evidently inferior in the softer social arts. The Greeks called them Dorians, a name afterwards associated with the most distinctive, but the least cultivated, of the historic races of the peninsula--a race, however, possessed in its full form of the conception of the city-state; which implied the subordination of the individual to the corporate body, and was the chief social message to be taught thereafter by the Greek to the world. Without calling these invaders by any one name, or supposing Northern folk to have made then their first appearance in the Ægean area, we may safely see in this Greek tradition the record of a cataclysmic change out of which historic Hellenism was to issue at the last. In proof of the invader’s inferiority in the useful arts we have the undoubted fact that the command of the Greek seas, formerly held by Cretans and other Ægean folk, passed for some centuries into Semitic hands--the hands of those Sidonian Phœnicians whose coming, but as yet incomplete, “thalassocracy,” is reflected in the most important of contemporary documents, the Homeric lays, and, under the lead of the Tyrians, was to grow greater yet. To illustrate their inferiority in the luxurious arts we have the dry, uninventive style of artistic decoration known as the “Geometric,” which also lasted for some centuries. It is evident that the newcomers were conquering soldiers, who destroyed, but could not of their own virtue create. [Illustration: A GREAT CITY OF ANCIENT CIVILISATION: THE BUILDING OF CARTHAGE BY DIDO From the painting by Turner, in the National Gallery. ] Now, the course of events after all such conquests, if permanent but not exterminative, is the same. The rude military invaders, finding themselves deficient in woman-folk, take not only slaves but wives from the civilised people of the soil. The resultant children tend more and more, as time goes on, to be influenced by their native mothers. In them previous culture begins to revive, and ere many generations are past, so completely is the new race assimilated by the old that the language in general use is that not of the conquerors but of the conquered. [Sidenote: Hellas and its Conquerors] [Sidenote: The New Civilisation in Greece] For a crucial instance we need look no further than to the after history of the Norman invaders of Britain; and we might almost assume, were there no actual memorials of the fact, that the civilisation which arose anew in the Ægean area, after the tumultuous period reflected in the Homeric lays and the Greek tradition of early Asiatic colonisation, was largely influenced by what had been there in the Ægean Age. There is, however, proof that such was indeed the fact. As will presently be pointed out, the long period of unrest had allowed other alien influences to enter Hellas notably the Semitic from Phœnicia. But beside what appears to be Asiatic, and also beside what was new and distinctively Hellenic in the historic culture, which became prominent from the ninth century onwards (and this includes such all-important features as the conceptions of a supreme Father-God, and of the city-state--an idea of social order as obdurate to southern influences as our own Germanic social order has proved)--beside all this, the “non-Hellenic” elements in the civilisation are almost entirely such as may be referred to Ægean prototypes. Hellenic art, which flourished pre-eminently among the non-Dorian inhabitants, is distinguished from Eastern art by just those distinctive qualities of both realism and idealism which distinguished the highest art of the Ægean Age. Hellenic religion has for its oldest, most universal, and most popular deities various feminine impersonations, indistinguishable from the earlier Mother-Goddess. The chief of these is the unwedded Artemis-Aphrodite, supreme patroness of life all through the historic period of pagan Greece, the essential features of whose cult are still dominant in the observance of the Greek peasant-worshippers of the Christian Virgin. Hellenic cult is full of interesting survivals of the Tree and Stone ritual amply attested in Ægean cult. Hellenic custom retained many traces of a matriarchal system, appropriate to a society exclusively devoted to the Great Mother, whom Hellas took in name and actual primitive form to her pantheon under the names of Rhea and Kybéle. The Dorian and Ionian styles of architecture can be directly affiliated to the Ægean as revealed in Mycenæan tombs and Cnossian frescoes, and the Greek house is a development of the earlier domestic plan. Certain notable exceptions go far to prove the rule. The dress of the upper class, and the fashion of body-armour and weapons, seem to have been determined henceforth by the new folk. These are just the features in civilisation which conquering invaders would naturally introduce and retain. It is hardly necessary to add that if Ægean civilisation seriously influenced that of historic Hellas, it seriously influenced at second hand that of Western and Central Europe. [Illustration: ATHENS IN THE HEIGHT OF HER CIVILISATION: THE MARKET PLACE RECONSTRUCTED WITH THE ACROPOLIS IN THE BACKGROUND] [Sidenote: Other Ægean Influences in Europe] [Sidenote: Commercial Communication with Europe] Hellenic civilisation, however, was perhaps not the only medium through which Ægean influence affected inner Europe. In Scandinavian tomb-furniture certain presumably foreign decorative motives, notably the returning spiral and the _triquetra_, which are identical with characteristic Ægean types, make their appearance in the first part of the local Bronze Age; and these have been noticed also, at a slightly later period, in the art of early Ireland, at that time the most civilised of the British Isles. In point of form also some Northern weapons in bronze resemble those of the Far South. If the spiral motive stood alone, the affiliation of this distant decorative art to the Ægean would be very doubtful, since Nature, whether through the forms assumed by vegetable tendrils or animal horns, or through those of shavings of wood or metal, might easily have suggested the ornament independently. But taken together with other related motives, and the evidence of assimilation of weapon-forms, these spirals raise a presumption in favour of an early obligation of North Europe to Ægean civilisation. A possible explanation of this fact, if fact it be, has been found in the communication which appears to have been created by the Ægean demand for Baltic amber; and early ways for this traffic have been traced by Dr. Arthur Evans up the Adriatic, and also overland from the Ægean shores to the Danube basin, whence, from a point near the later Carnuntum, a combined route ran up the Moldau to the Elbe system. Further, it is the opinion of Professor Montelius and some other archæologists that not only certain bronze forms and decorative motives, but the usage of this metal itself was derived in Scandinavia from the south, somewhere before 1000 B.C. Since pure copper and pure tin hardly occur in Sweden among objects of this age, it has been held that the bronze was imported ready made in the mass. But Sweden contains large natural copper deposits, and tin is also found; and, therefore, this opinion is not universally accepted. Indeed, some authorities reverse the debt, and actually derive Ægean knowledge of bronze from Europe. If, however, the first derivation be ever proved, we shall have to refer the first use of metal weapons--an enormous step forward in social progress--in North and Central Europe to the Southern civilisations, such as the Egyptian, which had certainly known and used bronze for at least a thousand years before we find it in Sweden. It is sometimes maintained that Cyprus was the first, and long the sole, source of copper, which travelled north by way of Asia Minor and the Ægean to Hungary and inner Europe; but this is not proved. In any case, for some reason, bronze seems to have become known to the Scandinavians and Danes earlier than to the Gallic peoples. [Sidenote: Influences in Western Europe] Yet more evidence is there of possible Ægean communication with Central Europe after the introduction of iron, which seems not to have reached Scandinavia till almost the Christian Era. Transylvanian, Russian, and Balkan graves have yielded to recent explorers abundance of both weapons and decorated articles of personal use and adornment, closely resembling fabrics in the later periods of Ægean civilisation. Further into the European continent we have again the various evidence of the early Iron Age graves of the Salzkammergut on the south-eastern fringe of the Bavarian plain. This “Hallstatt” culture, as it is called, from the location of the chief cemetery, presents both in character and development an extraordinarily close parallel to that of the Ægean Geometric Age. About the same period we know also that a civilisation was in progress in the fertile lands round the head of the Adriatic, which is called Veneto-Illyrian, and shows even stronger evidence of Ægean influence than the Hallstatt culture; as, indeed, might be expected, if it be remembered that in Southern and Central Italy, as well as Sicily, forms and decoration, obviously learned from Ægean civilisation, as well as actual imported Ægean objects, had been plentiful ever since the bloom of the Ægean age. A visit to the local collections in Syracuse, Bari, and Ancona, will establish this fact to the satisfaction of any archæologist. These two civilisations, that of the Salzkammergut and that of the North Adriatic lands, have important bearing on the development of all Western Europe; for we know that the Celtic peoples, who penetrated south of the Alps in the sixth and fifth centuries B.C., learned much from both, and especially from the second; and graves, furnished after they had been pressed back again into Switzerland and Gaul, show abundant evidence of what is called “sub-Ægean” influence--that is, of form and ornament probably derived ultimately from Ægean culture, but indirectly, or after undergoing considerable degradation. Through various subsequent intermediaries, notably the Belgic tribes, these derivatives passed ultimately to our own islands, and we find their influence operative on early English art. [Sidenote: Civilisations Help One Another] At the same time it is necessary to add that this derivation of the higher developments of mid-European and Scandinavian culture in the Bronze and Early Iron ages from the influence of Ægean civilisation is far from certain, whatever be the case for the Adriatic lands. Knowledge obtained since Dr. Evans and Dr. Montelius first expressed their views, especially in regard to the so-called Neolithic or “Butmir” pottery, which has a very wide range in South-Eastern Central Europe, has not strengthened their case, but rather tended to suggest that the continental culture developed independently to, though in a parallel direction with, that of the southern peninsulas and isles. If this view ultimately prevail, it will illustrate the opinion, to which we personally incline, that the derivation of civilisations, one from another in early times, is the exception and not the rule, except in respect of minor matters. [Sidenote: The Vigorous Hittite Civilisation] Two other intermediary civilisations of the South-east remain to be considered--the Hittite and the Phœnician. The first is still, unfortunately, very little known to us, and we are hardly in a position to say much about its influence on Europe until more small objects of use and ornament have been discovered on Hittite sites. The general facts so far ascertained, which make such influence probable, are these. This civilisation, characterised and distinguished from all others by a very individual art, and by a system of writing apparently independent of the Mesopotamian and Egyptian systems, but in its later development showing kinship to Mediterranean systems, lay across all the mainland routes from inner Asia and Egypt to South-eastern Europe. Its monuments have been found scattered thickly from the valley of the Syrian Orontes northwards, to within 150 miles of the Black Sea, and westward to the last passes which lead down from the Anatolian plateau to the Ægean littoral. So far as we can judge at present, its place of origin was Cappadocia, but its later focus was possibly in North Syria; while its period of florescence ranges back from about the sixth century B.C. for at least a thousand years. It was, as we know from many written records, in frequent collision with both Egypt and Assyria, and in its southern home and latest period came under Mesopotamian domination. As is to be expected, therefore, its monuments show very strong Mesopotamian, and less strong Egyptian, influence. At the last, indeed, those of North Syria approximate very closely indeed to the contemporary Assyrian of the Sargonid Age. At the same time, however, they retain sufficient individuality never to be mistaken for other than Hittite; they represent facial types, dress, and fashion of arms which are peculiar; and the inscriptions they bear are always couched in a script having no relation to cuneiform writing. [Sidenote: Europe and Hittite Influence] This vigorous civilisation, occupying the great land bridge from Asia into Europe in the dawn of the historic Hellenic period, and eminently receptive of Mesopotamian influences, cannot but have been a medium through which these reached the Ægean Sea, and so told on Europe. But this did not take place to any appreciable extent in what is known as the prehistoric period. The Cretan products, and those of the other Ægean Isles and mainland Greece, betray very little Mesopotamian influence, and none that we can reasonably trace to the Hittites. So far as we can see, the Ægean culture was much more ancient than the Hittite, and if there was kinship between them we are bound, on the evidence, to derive the latter from the former, and not vice versa. There is a certain relation between late Ægean art and products of inland Asia Minor, but it indicates influence passing eastward rather than westward; and even on the remoter Ægean sites of Asia Minor--Hissarlik, for instance--non-Ægean traces are but slight, and do not suggest the influence of a strong civilisation focused inland. [Sidenote: The Hittite Pathway of Civilisation] [Sidenote: Part Played by the Phœnicians] In the early Hellenic Age, on the other hand, we have to note considerable Mesopotamian influence on Greek culture, and, at the same time, certain evidence of counter influence, both sub-Ægean and Græco-Lydian, on Mesopotamia, which is as yet not fully understood. But whether both or either of these respective influences were transmitted through the Hittite civilisation is still very doubtful. The Egyptian influence on archaic Anatolia, especially on Rhodes, and even on the Greek mainland, seems clearly to have come by way of the sea; and considering the part which the Phœnicians had been playing for some time previously as transmitters of things eastern, there is a probable alternative westward route for Mesopotamian influence also. In Cyprus, at any rate, this influence, which at a certain period has left strong traces, certainly came for the most part through the western Semites. The claim of the Hittites, however, is not to be denied altogether. Their script seems undoubtedly to have been the parent of the Lycian and other local Anatolian systems. Phrygian art and writing attest Græco-Lydian influence inland; Ionian culture was certainly not unaffected by the Lydian in which many students recognise a western offshoot of the Hittite; and there are a few features in Ionian cult and in cult representations which seem to be owed rather to the religious system of the central plateau than to that native to the Ægean area. In this state of suspense we must leave the question, adding only these final remarks, that Greek tradition itself ascribed some of the arts and luxuries of its civilisation--for example, the coining of money--to Lydian invention, and also affiliated to Lydia a whole western culture, that of Etruria; while it is an undoubted fact that a Mesopotamian standard of weight-currency travelled to the Ægean, and thence affected all western commerce, but by what channel we do not certainly know. There is an unknown quantity in all this problem--viz., Lydia. We have reason to suspect the latter of a considerable influence on early Hellenic civilisation, both as creator and transmitter, but must await further evidence. The part played by the Phœnicians in transmitting influences of civilisation from East to West is far more certain, and is now much better understood than it was a few years ago. Much vague exaggeration of it has been swept away by recent demonstration that there is practically nothing of probable Phœnician origin in the remains of the Ægean culture. The script of the latter is wholly independent; the typical Phœnician vehicles of glyptic art, the cylinder and the scarab, were never naturalised in the early Ægean; the whole path of the latter’s artistic development was distinct; and the Ægean religious representations, once regarded as Semitic, are now seen to be native. On the other hand, decadent and derived Ægean forms and motives appear among the earliest Phœnician known to us. Influence, if it passed at all, between the Ægean and the Syrian coast lands, in the prehistoric age, moved from west to east. [Sidenote: Origin of Our Written Language] [Sidenote: Semitic Influence in Greek Art] In short, we now know that the Phœnicians did not begin to spread over the western sea and influence Europe till the break up of the Ægean civilisation. The Homeric lays and Hellenic myths reflect the inception of a Semitic expansion, which must be placed after 1100 B.C. Even in Homer there is more mention of Greek ships than of Sidonian, and the Tyrian power is yet to come. The latter pushed westward later, and the founding of Carthage, usually dated in the eighth century, marks its first great achievement along those distant sea-routes, which certainly the Semites had been coming to know during a couple of centuries of huckstering trade, even if the dependence of the early Hellenes on Phœnician knowledge of these waters has been overrated. But, in any case, during the interval between the fall of Ægean power and the rise of the Hellenic maritime cities these Semites counted for much. Even in the light of Cretan discovery, we need not question their responsibility for the Greek alphabet, and thus, indirectly, for the ultimate medium of written communication used throughout European civilisation; nor need it be doubted that Hellenic writers, who trace early instruction in trade and barter to visits of Semitic ships to their coasts, show real, though limited, knowledge of fact. Phœnician factories were certainly established on Greek shores, and left Semitic forms among later Greek place-names; and it is quite possible that political power was exercised at one time by Semitic colonists in parts of Hellas. Sufficient Phœnician art products have been found on archaic Hellenic sites, to prove that, in the period between 1000 and 500 B.C., the Ægean coasts were often visited by these Semites. Such objects are especially numerous in Rhodes, a convenient stage on the westward sea route, and they radiate over not only Ionia and the Hellenic lands, but also into the further Mediterranean, to Sicily and its neighbouring islands, to Italy and South Gaul, and to Sardinia and Spain. Carthage probably had much to say in their western distribution. [Illustration: ÆNEAS AND DIDO: THE QUEEN OF CARTHAGE LISTENING TO THE STORY OF THE SIEGE OF TROY From the Painting by P. Guerin, in the Louvre. ] [Sidenote: No Phœnician Influence in Britain] Of Semitic influence on archaic Greek art there is considerable evidence. After the Geometric Age, we find in the Greek lands pottery and metal-work showing certain motives and arrangement of decoration foreign to Ægean art, and referable ultimately to the Mesopotamian and Egyptian. Such are the animals and monsters disposed in concentric friezes and zones on Cypriote bowls, Corinthian vases, and the Cretan shields of the Idaean Cave. But this influence, strong and undoubted as it was, must not be over estimated. As the Hellenes rose to power, their instinct of sincerity and naturalism, inherited from Ægean civilisation, revolted against, and triumphed over, this parasitic Semitic art, and already in the ninth or eighth century we find a Græco-Lydian influence, which owes nothing to Phœnician, breaking back to the east and creating the ivories of the Sargonid Age at Nineveh. Phœnician objects thenceforward become fewer and fewer in Hellenic strata, and in the sixth century B.C. they virtually vanish. By this time Phœnicia had become a subject country, about to give up the last ghost of its independence to the Greeks themselves, as its western offshoot, Carthage, was also to surrender a little later to another civilisation near akin to the Greek. But, needless to say, the Semite has had his full revenge for the short tenure of his earliest predominance in European waters. The fall of Phœnicia cleared the way for another Semitic family to capture international trade, and, first with one creed and then another, to conquer the Greeks, the Romans, and the World. There are, of course, possibilities of direct Phœnician intercourse with non-Mediterranean Europe--for example, with England’s south-western coasts; but they need not detain us. For whether certain Semites came to Cornwall in quest of tin or no, it is certain that by these no lasting influence of civilisation passed in to England. Neither the religion, the speech, nor the script of Britain owed them anything. Recent scholarship tends to discredit any Semitic element even in English south-western place-names. [Sidenote: The Origins of our Civilisations] Such, in brief outline, are the channels through which the civilisations of the South-eastern river-valleys could communicate with primitive Europe. It is easier to point them out than to say exactly what flowed along them. Seldom can so definite a debt be recorded as that under which we lie to the Semites of Phœnicia, for the names and the forms of the written characters which, presumably, they themselves had borrowed from Egypt, and modified ere they passed them westwards. Usually the obligation must be stated much more vaguely, being confined, as in the case of Ægean influences, to little more than a general responsibility for the spirit, and for many forms of the expression, of the first great artistic growth on the mainland soil of Europe, as well as for certain persistent and dynamic features in South European cults. Thus, it becomes even more apparent at the end of our discussion than it was at the beginning that when all has been said about influences of Egypt and Mesopotamia, and influences of the intermediate civilisations of the Ægean, Syria, and Asia Minor, only a very small part of the whole story of incipient European civilisation has been told. Nor is it to be expected that the origin of our culture should be capable of being adequately expressed in terms of other cultures, developed at a great distance and under different geographical conditions. Civilisations, destined to be living growths, spring, it seems, of themselves, and the debts which they can incur at the first are very small and mostly in small things. It is only when they are come to adult estate, have bred men of wealth and leisure with open and receptive minds, and have broken through the geographical barriers about them, that they begin to borrow at large. [Sidenote: In the Childhood of Europe] One of the intermediate civilisations of which we have treated, the Ægean, the only one whose own origins are fairly well known, offers proof in point. Its remains indicate but trifling obligations to neighbouring Egypt till a very late period, that which, in Crete, we call the Third Minoan. Thereafter, in the space of two or three generations, the evidence of its debt increases at a wholly disproportionate rate. So too, no doubt, in the misty period of the childhood of Central and Western Europe, little was borrowed from abroad that was essential to civilisation; and the heavy obligations which we owe to the Eastern lands fall in ages much more recent. They fall, in fact, in those times which saw the Anatolian cult of Kybéle and Attis, the Egyptian cult of Isis and Horus-Harpocrates, the Mesopotamian cult of Mithra, and, far more momentous, of course, than these, Christianity--Hebrew in origin if modified by Greek conceptions--brought by a greater intermediary civilisation than any with which we have had to deal, to the knowledge of inner European races already long emerged from savagery, and able and eager to borrow. DAVID GEORGE HOGARTH [Illustration: THE TRIUMPH OF RACE WHY ONE NATION CONQUERS ANOTHER BY DR. G. ARCHDALL REID] It is a familiar fact that offspring resemble their parents on the whole, but differ from them in details. For example, the child of a human being is always another, but never an exactly similar, human being. These differences in detail are of two sorts, _inborn_ and _acquired_. Inborn or innate differences arise “by nature”; the child is inherently unlike the parent--taller or shorter, fairer or darker, and so forth. Acquired differences, on the other hand, are due to the conditions under which parents and children have lived. Thus, owing to better or worse surroundings, the child may develop better or worse than the parent and so be taller or shorter, or a greater exposure to weather may render him darker or fairer. [Sidenote: Things We Cannot Inherit] It was formerly believed by scientific men, and is still believed by the public, that traits acquired by the parent tended to be inherited by the child--that is, reproduced as inborn traits. Thus it was supposed that if a man were made strong by exercise, or injured by accident, his child would tend to inherit, in some degree at least, the acquired benefit or injury, and as a result be naturally stronger or more defective than the parent was at the start. [Sidenote: Acquired Traits not Hereditary] But very prolonged and careful investigation has proved that this is certainly an error. For example, though for æons human beings have been learning to speak and walk, and make a multitude of other acquirements, yet none of these are ever inherited. In fact, owing to the evolution of memory and the retrogression of instinct, man, of all animals, acquires the most and inherits the least. Every child has to begin afresh and learn what its ancestors learnt; all are born ignorant; none speak or walk “naturally.” Each starts where the parent began, not where he left off. The parental traits, if reproduced at all, are always of the same kind in the child as in the parents, and appear in the same way. That is, the inborn traits of the parent are always inborn in the offspring; the acquired traits are never anything but acquirements resulting from the same causes as they did in the parent. In brief, the acquirements of the parent are never transmuted into inborn characteristics in the child. They are never inherited. It is admitted on all hands that inborn differences--_variations_, as they are termed technically--tend to be inherited. Thus, if the parent is naturally darker than the grandparent, the child tends in colour to resemble the former more than the latter. Since the child may vary from the parent in the same direction as the latter varied from the grandparent, these inborn differences may be accentuated in subsequent generations. It is due to this fact that plant and animal breeders have improved domesticated species. They are able to benefit the individual by improving his surroundings, but the race they can improve only by breeding from the best. In other words, when they have the latter end in view, they must build on natural variations, not on acquirements. [Sidenote: A Great Problem of Science] [Sidenote: Differences among Kindred] One of the most important problems in the whole range of science is the question as to what causes offspring to differ in this inborn, natural way from their parents. Many theories have been formulated, and the subject is still to some extent under discussion; but the evidence is overwhelming that variations--natural differences--are not generally caused, as most people believe, by anything that happens to the parent before the birth of the child, but are “spontaneous.” The subject is a large and intricate one, and we have not space to discuss it at length. One or two facts, however, may be mentioned. The members of a litter of puppies, kittens, or pigs, may differ naturally amongst themselves and from their parents in all sorts of ways--in colour, shape, size, hairiness, disposition, and so on. One puppy may present points of resemblance to the father, another to the mother, a third to some ancestor, while a fourth may be unlike any of its predecessors. Since, practically speaking, the puppies were all conditioned alike before birth, it is evident that these great differences must be “spontaneous.” They cannot have been caused by such things as the good or ill health of the parents, their food, or the life they led, for, in that case, the puppies would all have varied in the same way. Again, malaria is, in effect, a universal disease on the West Coast of Africa. Individuals differ naturally in their powers of resisting it, some taking it lightly and some severely; but almost every negro suffers, and many children perish of it. If the sufferings of the parents caused children to be born weaker “by nature,” it is evident that every individual would start life inferior to his predecessor at the start, and the race would thus degenerate and ultimately become extinct. On the other hand, if variations are “spontaneous,” if, quite unaffected by the sufferings of the parents, some children are born naturally different, naturally more or less resistant to malaria than their predecessors, it is plain that the weeding out of the unfittest, the weak against the disease, would ultimately make the race resistant to it. In the one case the race would drift to destruction; in the other it would undergo protective evolution. Obviously, the latter is what has happened. Negroes show no signs of any kind of degeneration, but they are of all races the most resistant to malaria. [Sidenote: Suffering Produces Strength] Similarly, Englishmen who have been much exposed to consumption and measles, natives of India who have been much afflicted by enteric fever and dysentery, Esquimaux who have suffered from cold, Arabs who have endured heat, Chinamen and Jews who have long dwelt under that complex of ill conditions found in slums and ghettos, are none of them degenerate, but, on the contrary, have become resistant, each race to its own particular ill-conditions in proportion to its sufferings in the past. In fact, it may be laid down as a general rule that races strengthen only when exposed to ill conditions, and deteriorate only when the conditions are so favourable that the unfit are not eliminated. An example of the latter is seen when prize breeds of animals and plants, however well nourished and cared for, are no longer bred with care. It follows that races, if not exterminated, are not injured but strengthened by ill conditions, by the elimination of the unfittest, as gold is refined by fire. [Sidenote: Survival of the Fittest] It is a remarkable fact that many people are able to accomplish the surprising feat of knowing that races have become inured to ill conditions, and of believing at the same time that the offspring of people exposed to such conditions tend, as a rule, to be degenerate. It is as if they believed that two and two make four, and two more six, but that if a great number of two’s are added together the total result is a minus quantity. Obviously the two beliefs are incompatible. A race cannot degenerate in every generation and yet emerge in the end strengthened from the struggle. The confusion has arisen because the two diametrically opposite propositions are seldom considered together, and in part also from a mistaken interpretation of what is observed in such situations as the slums of cities. Here puny children are seen to be derived from puny parents, and it is assumed that the children are degenerate because the parents have suffered. As a fact we have no reason to doubt that the children are affected in precisely the same way as the parents. On the one hand, slums are sinks into which descend people naturally inferior, people who have varied spontaneously from their ancestors in such a way as to be feeble, physically or mentally, and who reproduce their like. On the other hand, the conditions are such that even the naturally strong, both parents and children, develop badly. Doubtless, owing to the constant elimination of the unfit, the latter--the naturally strong--are by far the more numerous. There is nothing to show that, if they were removed in early life to better surroundings, they would not develop just as well as the offspring of country folk. [Sidenote: An Evolution that has now Ceased] The fact that races grow resistant to the ill conditions to which they are exposed, and degenerate when placed under particularly good conditions, is decisive proof that offspring are not, as a rule, innately affected by the surroundings of their parents. No doubt exceptions occur, but these are amongst the most unfit, and the race is soon purged of them. Thus European dogs are said to degenerate when taken to India. But the existence of old-established native races of dogs is proof that the degenerative process is not perpetual. Malaria and many other ill conditions are quite normal parts of the environment of the races exposed to them, and have been so for thousands of years. Except for occasional unfavourable variations, which are quickly eliminated, they have long purged the races of those strains that tended to become degenerate under their influence. After man--through the evolution of the structures and faculties which distinguish him from the lower animals, the large brain, with its accompanying memory, the organs of speech, the hand, the erect attitude--had achieved the conquest of the earth, his selection and evolution along the ancestral lines gradually diminished, and has now almost ceased. At the present day clever, strong, or active people do not on the average have an appreciably more numerous progeny than those who are not exceptionally endowed. No modern race is intellectually superior to the Greeks who flourished more than two thousand years ago. The brains, the hands, the organs of speech, the erect attitude, have not altered. Apparently nothing more than traditional knowledge has improved. The gradual accumulation of traditional knowledge during prehistoric times enabled man to cultivate animals and plants, and so to increase and regulate his supply of food. As a consequence his numbers multiplied. Areas of country which formerly supported only a few wandering hunters now afforded sustenance to growing multitudes of agriculturists, who often dwelt together for mutual protection in villages. Commerce followed agriculture, towns and cities arose, and civilisation dawned. Civilisation implies a dense and settled community, protected from most of the dangers which beset wild animals, and in which, therefore, the elimination of the unfit is no longer of the kind that weeded out the brute and the utter savage. Some sort of elimination does occur, however, for, even in the most civilised states, multitudes of people perish in youth, before they have contributed their full quota of offspring to the race. [Sidenote: Natural Selection at Work] We have excellent opportunities of studying this elimination and noting whether it results in evolution. Indeed, man presents the only instance in Nature in which we are able to observe natural selection actually at work. In all modern states statistics are compiled which set out the causes of death, the mortality from each cause, and the ages of its victims. By comparing races which have been much afflicted by this or that cause of mortality with races that have been little or not at all affected, we are able to ascertain the resulting racial change, if any. As may be noted by everyone, _civilised people perish, with rare exceptions, of disease_. MANKIND’S LONG BATTLE AGAINST BACTERIA [Sidenote: Resistance of Races to Disease] We have just seen that every race is resistant to every disease precisely in proportion to its past experience of it. It follows that the evolution of civilised peoples is against disease. If any other kind of evolution is now occurring, no one as yet has been able to demonstrate it, though many unproved guesses have been made. Mere alterations in traditional knowledge is not evolution. Children may derive it just as well from other people as from their parents. The vast majority of deaths from disease are of zymotic origin. A zymotic or microbic disease is caused by the entrance into the body of minute animals or plants (microbes), which find their nutriment there. There are many species of microbes, each disease being due to one. Some species are mainly air-borne, and infect through the breath; others are water-borne; others earth-borne; yet others insect-borne; while a few pass by actual contact from an infected to a healthy person. [Sidenote: The Way Disease is Spread] Some diseases--for example, consumption and leprosy--are of indefinite but always prolonged duration; others, like measles, are short and sharp. In the case of the latter, for reasons we need not dwell on here, the body after an attack becomes, for a longer or shorter time, an unfit habitation for the microbes of that particular species. The rapid recovery which occurs in these “acute” diseases, indeed, implies the banishment of the microbes. The air-borne diseases--measles, influenza, smallpox, and the like, all of that acute type which confers immunity against subsequent attacks--are very infective, spreading through a susceptible population with great rapidity. Under favourable conditions the water-borne diseases also--cholera, dysentery, enteric fever, and the like--may spread very quickly. Chief amongst the earth-borne diseases is consumption. It is contracted chiefly in such dark, ill-ventilated, and crowded houses as are built by the inhabitants of cold and temperate climates. The disease-producing microbes are an infinitesimal proportion of the total number of bacterial and protozoan species. In Nature it is not easy to find a speck of earth or a drop of water from which these minute living beings are absent. All decay, by means of which the dead bodies of plants and animals are returned to the soil, is due to them. [Sidenote: The Immense Antiquity of Diseases] It is a safe assumption that the microbes of human diseases have evolved from non-parasitic species. The niche they now occupy in Nature is the human body. Two things formed essential parts of this evolution--first, the microbes became capable of existing and multiplying for a shorter or longer period in the body; secondly, they evolved means of passing from one living body to another. The latter must have been the more difficult process. Under favourable circumstances several species of microbes--for example, those of putrefaction, which are ordinarily non-parasitic--are capable of entering the human body and becoming virulent; but, since they cannot secure passage from one individual to another, they die out, and their virulence is lost. Historical evidence renders it probable that all known human diseases are of immense antiquity, the so-called new diseases being merely newly-observed diseases. It appears probable, therefore, that, owing to constant persecution by disease, by continued survival of the fittest, humanity has grown so resistant that no species of microbe which has not undergone concurrent evolution is now able to establish itself as a regular parasite. Obviously, since the microbes of human diseases draw their nutritive supplies from man, they cannot persist except amongst populations so crowded that they are able to pass from one individual to another in unending succession. When the succession fails, the disease dies out, and is not renewed, except from foreign sources. Microbic disease is never contracted in desert places far from human settlements, and even in modern times it is comparatively rare amongst nomadic tribes, and, seemingly, was quite unknown in Arctic regions and in many Pacific islands before its introduction by Europeans. These maladies, therefore, must have made their appearance only after men had peopled certain regions in considerable numbers. [Sidenote: Progress of Sanitary Science] On the other hand, we have no certain evidence that any well-established parasitic disease has ever completely died out. The chances are all against such an occurrence in the past. When once established as parasites, the microbes, owing to the constant growth of human population, found a constantly augmented food supply, and therefore constantly increased opportunities of reaching fresh fields of conquest. Sanitary science is still in its infancy. Preventive measures, and perhaps other agencies, have caused the disappearance of leprosy from several countries, but it is still prevalent in many quarters of the globe. Contagious diseases have spread very widely. Earth and air borne diseases have become endemic instead of merely epidemic. Consumption is always with us, and almost every child contracts measles, whooping-cough, chicken-pox, and common cold. Small-pox has been replaced by vaccination, which is merely modified small-pox. Malaria has spread but little during the historic epoch, but only because its microbes were already present in almost every place where the mosquitoes that convey it are able to exist. [Illustration: THE DAYS OF THE PLAGUE IN LONDON Dr. Archdall Reid, in his essay on race supremacy, explains that the evolution of civilised peoples is against disease, and the age of pestilence and plague is passing. This picture of an incident in the greatest plague that has affected London in historical times--in the year 1665--is from the painting by F. W. Topham, R. I. ] All our information indicates the Eastern Hemisphere as the place of origin both of man and of his microbic diseases. Parts of it have been inhabited by a dense and settled population from a time immensely remote. “Behind dim empires ghosts of dimmer empires loom.” Beyond the traces of the oldest civilisations we find evidences of primitive agricultural communities, and far beyond these the remains of the cave-men and hunters of the Stone Age. Even a race of hunters tends to increase faster than the food supply. Doubtless the pressure of population in the Old World led to the colonisation of the New. But even in the New World there are signs of a civilisation so ancient that some authorities have placed its beginnings as far back as a score or more of thousands of years. With the exception of malaria, it is extremely doubtful whether any zymotic disease existed in the whole of the New World at the time of its discovery by Columbus. The subject is involved in obscurity; but, while it is evident that the European adventurers introduced many diseases, there is no clear indication that they found and brought back one. Apparently all the diseases which have been prevalent in Europe and America during the last four hundred years were prevalent in the former continent before the fifteenth century. Venereal disease and yellow fever have sometimes been regarded as exceptions. But the former was well known to the Roman physicians, and was common during the Middle Ages. Moreover, the inhabitants of the New World take the disease in a very acute form, and it is not found in remote communities to which Europeans have had no access. Yellow fever was first noted with certainty in the West Indies in the middle of the seventeenth century. The records of the time “tell of the importation of the disease from place to place, and from island to island.” [Sidenote: Origins of Rare Diseases] Not till more than a century later was it observed on the West Coast of Africa. There can be no doubt, however, that the earlier observers confused yellow fever with bilious malaria, and that it was present both in the West Indies and Africa long before a differential diagnosis was made. The fact that of all races negroes are most resistant to the disease would seem to indicate West Africa as the place of origin. In any case, it is certain that, with the exception of malaria, zymotic diseases, if not entirely absent, were extremely rare in the New World. THE DISAPPEARANCE OF THE NATIVE RACES [Sidenote: The Age of Pestilence is Passing] Zymotic disease, then, arose amongst the slowly-growing populations of the Old World. Air and insect borne diseases may have arisen amongst the early hunters and nomads. Similar forms of disease, murrains as they were anciently termed--for example, distemper, rinderpest, the horse sickness in South Africa, the rabbit plague in Northern Canada, and the cattle fever in Texas--occur among lower animals, when these are present in considerable numbers. With the exception of tuberculosis and leprosy, endemic disease was probably almost unknown in the sparsely-peopled ancient world. The facts that air and water borne diseases spread very rapidly, that the illnesses caused by them are comparatively short and sharp, and that recovery is followed by immunity, must have caused rapid exhaustion of the food supply of the microbes. Under such conditions the persistence of the pathogenic species was maintained among the scanty populations by a passage to new and perhaps very distant sources of supply. Introduced by travellers, or spreading from tribe to tribe, they appeared suddenly in epidemic form as plagues and pestilences, and, disappearing as suddenly, were not known again till a fresh generation furnished a fresh supply of food. When, however, in spite of war, famine, and pestilence, the human race increased to such an extent that the number of fresh births furnished a perennial supply of food, while at the same time a rising civilisation and improved means of communication lessened the isolation of various communities, then many diseases slowly passed from an epidemic to an endemic form. Pestilence grew rare, but every individual was exposed to infection, and, during youth, either perished from, or acquired immunity against, the more prevalent forms of disease. [Sidenote: Measles a National Scourge] When endemic, zymotic disease--at any rate, disease against which immunity can be acquired--is far less terrible than when epidemic. Modern examples of ancient epidemics may be seen in isolated regions. In Pacific islands, for example, air-borne disease spreads like a flame. The whole community is stricken down. The sick are left untended and perish in multitudes. The entire business of the community is neglected, and famine frequently follows. Under such conditions measles or whooping-cough, diseases which we in England are accustomed to regard as scarcely more than nuisances, may rise to the level of a great national disaster. Thus, in 1749, 30,000 natives perished of measles on the banks of the Amazon. In 1829 half the population died in Astoria. In 1846 measles committed frightful ravages in the Hudson Bay territory. More recently a quarter of the total inhabitants was swept away in the Fiji group of islands. [Sidenote: Sanitation is Sometimes Powerless] At the dawn of history, long after the evolution of zymotic disease, the population of the Eastern Hemisphere was still sparse and scattered. Even as late as the Norman Conquest that of England was barely two millions--about one-third of the number now present in London. Means of communication were poor and beset by dangers. A journey from York to London was then a more serious affair than a journey from London to San Francisco to-day. Water and air borne diseases were, therefore, absent during long periods of time. When they came they spread as epidemics. Accordingly we read of plague and pestilence; of diseases suddenly becoming epidemic and sweeping away a fourth or half of entire communities. Historians are apt to attribute these immense catastrophes partly to the bad sanitation of the period and partly to diseases which have died out of the world, or, at any rate, out of Europe. Doubtless they are right in a few instances. But, apart from diseases which spread under special circumstances from tropical centres, had sanitation, under modern conditions of intercommunication and crowding, tends to render water-borne disease endemic, not epidemic. Over air-borne disease it has no effect. Measles, whooping-cough, chicken-pox, influenza, common cold, and small-pox (in a modified form) are as common as ever. [Sidenote: Plagues “the Wrath of God”] The character of these ancient epidemics, their special symptoms as indicated in old literature, their sudden and portentous appearance, which men attributed to the wrath of God, their tremendous infectivity and rapid spread, their equally sudden and complete departure as of Divine anger assuaged, point rather to air and water borne diseases of the types now endemic and comparatively harmless among us, but still so fearful in their effects on isolated communities. Like the light flashed from a child’s mirror on a darkened wall, so they flickered and swept forwards and backwards from end to end of the Old World--from the Malay Peninsula to the North Cape of Norway, from Kamschatka to the south point of Africa. A parallel may be found in the recent epidemic of rinderpest amongst the herbivorous animals of Africa. Years might pass, old men might remember, the peoples might sacrifice to their gods; but when a fresh generation of those who knew not the disease had arisen, when the harvest of the non-immune was ripe and ready, the diseases would return to the dreadful reaping. Behind them the earth was heaped with the dead, and the few and stricken survivors grubbed for roots to satisfy their hunger. To-day sanitation has nearly abolished water-borne diseases, and, in a population largely immune, epidemics of air-borne disease, like a light thrown on a sunlit wall, are but faint shadows of that which they were in their old days of awful power. [Sidenote: Growth of Resisting Power] The progress of consumption was different; it was never truly epidemic. Owing to its low infectivity, to its lingering nature, to the fact that no immunity could be acquired against it, it did not spread suddenly when first introduced, but when once established its virulence did not abate within measurable time. In other words, it was endemic from the beginning. It made its home in the hovels of the early settlers on the land. In such situations--as in Polynesian villages--modern Englishmen do not take the disease. But their remote ancestors were more susceptible; they could be infected by a smaller dose of the bacilli. Gradually, as civilisation advanced, the conditions grew more stringent; men gathered into larger and denser communities, into hamlets and villages in which they built houses ill lighted and worse ventilated. With the rise of towns, and ultimately of great cities, the stringency of selection continually increased; and with it, step by step, the resisting power of the race. To-day Englishmen dwell under conditions as impossible to their remote ancestors as to the modern Red Indians. In fact, no race, especially in cold and temperate climates, is now able to achieve civilisation, to dwell in dense communities, unless it has previously undergone evolution against tuberculosis. But of this more anon. So during the long sweep of the ages microbic diseases strengthened their hold on the inhabitants of the Eastern Hemisphere, who in turn slowly evolved powers of resistance. In like manner antelopes grew swift and wild sheep active when persecuted by beasts of prey. Then, when the germs of disease were rife in every home and thick on the garments of every man, there occurred the greatest event in human history, the vastest tragedy. Columbus, sailing across an untracked ocean, discovered the Western Hemisphere. The long separation between the inhabitants of the East and West ended. The diseases of the Old World burst with cataclysmal results on the New. [Sidenote: 3,500,000 Destroyed by Small-pox] The ancient condition of the Eastern Hemisphere was reproduced in the West. Again we read of plague and pestilence, of water-borne and air-borne diseases coming and going in great epidemics, and of the famines that followed. Measles and cholera piled the earth with the dead. The part played by small-pox was even greater. When taken to the West Indies in 1507 whole tribes were exterminated. A few years later it quite depopulated San Domingo. In Mexico it destroyed three and a half millions of people. Prescott describes this first fearful epidemic as “sweeping over the land like fire over the prairies, smiting down prince and peasant, and leaving its path strewn with the dead bodies of the natives, who--in the strong language of a contemporary--perished in heaps like cattle stricken with murrain.” In 1841 Catlin wrote of the United States: “Thirty millions of white men are now scuffling for the goods and luxuries of life over the bones of twelve millions of red men, six millions of whom have fallen victims to small-pox.” But the principal part was played by tuberculosis. Air-borne and water-borne diseases generally left an immune remnant, but against tuberculosis no immunity could be acquired. Red Indians and Caribs could not in a few generations achieve an evolution which the inhabitants of the Old World had accomplished only after thousands of years, and at the cost of hundreds of millions of lives. Civilisation, which implies a dense and settled community with cities and towns, had suddenly become a necessity, but remained an impossibility to all the inhabitants of the temperate parts of the West. It is a highly significant fact that throughout the New World no city or town has its native quarter, whereas every European settlement in Asia and Africa has its native suburbs. The aborigines of the New World are found only in remote or inaccessible parts. [Sidenote: A Plague that Spread like Fire] The following is an example of the manner in which tuberculosis went to work: “The tribe of Hapaa is said to have numbered some four hundred when the smallpox came and reduced them by one-fourth. Six months later, a woman developed tubercular consumption; the disease spread like fire about the valley, and in less than a year two survivors, a man and a woman, fled from the newly-created solitude.... Early in the year of my visit, for example, or late in the year before, a first case of phthisis appeared in a household of seventeen persons, and by the end of August, when the tale was told to me, one soul survived, a boy who had been absent on his schooling.” The Caribs of the West Indies are almost extinct. The Red Indians are going fast, as are the aborigines of cold and temperate South America. The Tasmanians have gone. The Australians and the Maoris are but a dwindling remnant. As surely as the trader with his clothes, or the missionary with his church and schoolroom appears, the work of extermination begins on Polynesian islands. Throughout the whole vast extent of the New World the only pure aborigines who seem destined to persist are those which live remote in mountains or in the depths of fever-haunted forests, where the white man is unable to build the towns and cities with which he has studded the cooler and more “healthy” regions of the north and south. [Sidenote: Races that Decline before the Whites] Many explanations, or pseudo-explanations, have been offered to account for the disappearance of the natives. We are told that they cannot endure “domestication,” that they “pine like caged eagles” in confinement, that the change produced by civilisation makes them infertile, as the change produced by captivity makes some wild animals infertile, and so forth. But the only peoples who are disappearing are those of the New World, some of whom were by no means savage. In Asia and Africa are many tribes far lower in the scale of civilisation who have persisted in constant communication with dense and settled communities from time immemorial. Notwithstanding all that has been written, the people of the New World do not wither away mysteriously when brought into contact with the white man. They die as other men do of violence, or famine, or old age, or disease. But deaths from all these causes, except the last, are now comparatively rare amongst them--much rarer than formerly during the time of their perpetual wars. The vast majority die of imported diseases--exactly the same diseases as white men die of. But their mortality is invariably much higher than that of white men, and they perish on an average at a younger age. [Illustration: THE EVE OF “THE VASTEST TRAGEDY IN HISTORY”: COLUMBUS SIGHTING AMERICA “The greatest event and the vastest tragedy in human history” is Dr. Archdall Reid’s striking description of the discovery of America by Columbus. It ended the long separation between the inhabitants of East and West, and the diseases of the Old World burst with cataclysmal results upon the New. The picture, by George Harvey, shows Columbus approaching America, his rebellious crew pleading for pardon.] All this is not mere hypothesis. It can be proved by reference to carefully collected and tabulated statistics published by every department of Public Health in America, Australasia, and Polynesia. The cause of the sterility cannot be demonstrated with the same precision; but it is hardly necessary to invent fanciful causes when a reasonable one is to hand. The high mortality indicates a high sick-rate, and presumably illness is as much a cause of sterility in the New World as in the Old, among savages as among civilised people. The Spanish conquest of the West Indies was followed by the swift disappearance of the natives. To that end the Spaniards unconsciously adopted the most effectual means possible. They satisfied their greed by forcing the natives to labour in plantations and in mines, and their religious enthusiasm by compelling attendance in churches and cathedrals. In other words, they placed the natives under conditions the most favourable for acquiring the diseases which they imported by every vessel. When the native population dwindled, it was replaced by negro slaves from West Africa. [Sidenote: Africans Die in our Civilisation] The history of negro migrations is extremely interesting and illuminating. There are no accounts of negro conquest outside the limits of Africa, but from very ancient times a constant stream of slaves has passed to Southern Europe and Asia, where they have been employed mainly in domestic service, and in more modern times to America, where their occupation has been mainly agricultural. The invasion of Asia has continued to our own day. But one may search from Spain to the Malay peninsula and, except in recent importations, find scarcely a trace of a negro ancestry. Yet slaves, like cattle, are valuable property, more cheaply bred than imported. In Eastern countries they have often been kindly treated, and many have attained to wealth and power. Like the African soldiers in Ceylon, of whom it is recorded that, though many thousands were imported by the Dutch and English, hardly a descendant survives, all perished in a few generations, the elimination of the unfit being so stringent as to cause extinction, not evolution. A permanent colony of native Africans in the midst of an ancient consumption-infested civilisation is impossible. [Sidenote: Fate of Natives of America] The fate of the negro migrations into America has been different. The race had undergone some evolution against consumption in Africa, and, therefore, was more resistant than the vanishing aborigines. In its new home, employed in agriculture in a hot climate where white men and tubercle bacilli, also recent importations, were as yet few in numbers, it was placed under the best conditions possible. Gradually, as the stringency of selection waxed, it evolved resisting power. To-day, American negroes are able to dwell even in Northern cities, though it is said “every other adult negro dies of consumption.” After the discovery of America the principal maritime races of Western Europe competed for its possession. Spain and Portugal, then powerful nations, had the first start in the race, and chose the seemingly richer tropics. But the forests of the centre and south were defended by malaria, which raised a barrier against immigration, and by heat and light, which raised a barrier against tuberculosis. Moreover, the Spaniards and the Portuguese intermarried freely with the aborigines, and the mixed race which resulted inherits in half measure the resisting power of both stocks. At the present day this mixed race, with a leavening of mulattoes, pure Spaniards, Portuguese, and negroes, inhabits the cities and more civilised parts. Even in tropical America the pure aborigines are found, speaking generally, only beyond the verge of civilisation. Farther south the disappearance of the natives has been more complete, and the cooler, healthier, and more open pampas are settled by a race more purely European. THE TRIUMPH OF THE ANGLO-SAXON PEOPLES [Sidenote: Expansion of the Anglo-Saxon] The weaker British and French were shouldered into the seemingly inhospitable north. But the British won the battle of Quebec, and the French immigration soon ceased. That little fight is half forgotten, but it is doubtful if any battle in history had results half so important. It placed all North America in the grasp of the Anglo-Saxon, and gave his race enormous space for expansion. Unchecked by malaria, the new-comers gathered into communities and built towns and cities such as those which across the Atlantic were the homes of tuberculosis. The cold forced them to admit little air and light into their dwellings. The aborigines melted away from the borders of the settlements. Under the conditions there was little intermarriage. In that climate Indian women, and even half-caste children, could not exist within stone walls. The few white men who took native wives preserved them only while living a wild life remote from their kin. The British conquest of North America and Australasia resembles the Saxon conquest of Great Britain. The natives have been exterminated within the area of settlement. It is in sharp contrast to their conquests in Asia and Africa. Both in the Old World and in the New the subjugation of the natives was accompanied by many wars and much bloodshed, and probably the conflicts in the former were more prolonged and destructive than those in the latter. But in no part of the Old World have the British exterminated the natives. They do not supplant them; they merely govern them. Southern Asia and East and West Africa are defended by malaria. The British cannot colonise them, and the natives have undergone such evolution against tuberculosis that they are capable of resisting the hard conditions imposed by modern civilisation. In South Africa, where there is little malaria, Europeans share the land with the natives, but the latter are likely to remain in an overwhelming majority. [Illustration: WHERE THE ANGLO-SAXON RACE OBTAINED POSSESSION OF NORTH AMERICA On the Plains of Abraham, outside Quebec, the British and French troops fought in 1759, and the battle placed all North America in the grasp of the Anglo-Saxon, giving his race enormous space for expansion. It is doubtful, says Dr. Archdall Reid, if any battle in history had results half so important as this, although it is half forgotten. ] If history teaches any lesson with clearness it is this--that conquest, to be permanent, must be accompanied with extermination, otherwise in the fulness of time the natives expel or absorb the conquerors. The Saxon conquest of England was permanent; of the Norman conquest there remains scarcely a trace. The Huns and the Franks founded permanent empires in Europe; the Roman Empire, and that of the Saracens in Spain, soon tumbled into ruins. It is highly improbable, therefore, that the British will retain their hold on their Old World dependencies. A handful of aliens cannot for ever keep in subjugation large and increasing races that yearly become more intelligent and insistent in their demands for self-government. But no probable conjunction of circumstances can be thought of that will uproot the Anglo-Saxons from their wide possession in the New World. The wars of extermination are ceasing with the spread of civilisation. We have ransacked the world, and now know every important disease. Diseases cannot come to us as they came to our forefathers and to the Red Indians, like visitations from on high. All the diseases that are capable of travelling have very nearly reached their limits; the rest we are able to check. Even in the unlikely event of a new disease arising, it would affect other races equally. Canada and Australasia, like the United States, may separate from the parent stem, but the race will persist. If ever a New Zealander broods over the ruins of London, he will be of British descent. [Sidenote: The Natural History of Mankind] The natural history of man is, in effect, a history of his evolution against disease. The story unfolded by it is of greater proportions than all the mass of trivial gossip about kings and queens and the accounts of futile dynastic wars and stupid religious controversies which fill so large a space in his written political history. In the latter, as told by historians, groping in obscurity and blinded by their own preconceptions, men and events are often distorted out of all proportions. A clever but prejudiced writer may pass base metal into perpetual circulation as gold. Luther and the Reformation are accepted as Divine by many people; they are reviled as diabolical by more. Cromwell was long regarded as accursed; to-day he is half-deified. How many of us are able to decide, on grounds of fact, not of fiction, whether the Roman Empire perished because the Romans, becoming luxurious, sinned against our moral code, as ecclesiastic historians would have us believe, or because a disease of intolerance and stupidity clouded the clear Roman brain and enfeebled the strong Roman hand, as Gibbon would have us think? But the natural history of man deals, without obscurity and without uncertainty, with greater matters. Study it, and the mists clear away from much even of political history. We see clearly how little the conscious efforts of man have influenced his destiny. We see forces unrecognised, enormous, uncontrolled, uncontrollable, working slowly but mightily towards tremendous conclusions--forces so irresistible and unchanging that, watching them, we are able even to forecast something of the future. The mere political results of man’s evolution against disease are of almost incalculable magnitude. The human races of one half of the world are dying, and are being replaced by races from the other half. Not all the wars of all time taken together constitute so great a tragedy. A quite disproportionate part in this great movement has been borne by our own race. It has seized on the larger part of those regions in which the aborigines were incapable of civilisation, because incapable of resisting consumption, and were undefended by malaria. In the void created by disease it has more room to spread and multiply than any other race. [Sidenote: Disease Mightier than the Sword] Other races may dream of foreign conquests, but the time for founding permanent empires is past. There remains for them only temporary conquest, in a few malarious parts of the world in which Europeans cannot flourish and supplant the natives. Spain and Portugal lost their opportunity when they turned from the temperate regions and chose the tropics. France lost her opportunity on the Heights of Abraham. Germany is more than a century too late in the start. Russia can conquer only hardy aliens who will multiply under her rule and ultimately assert their supremacy. In times now far remote in the history of civilised peoples, the sword was the principal means for digging deep the foundations of permanent empires. Its place was taken by a more efficient instrument. A migrating race, armed with a new and deadly disease, and with high powers of resisting it, possesses a terrible weapon of offence. But now disease has spread over the whole world and so is losing its power of building empires. The long era of the great migrations of the human race, of the great conquests, is closing fast. [Sidenote: Possibilities of the Black Races] It is generally supposed by historians and others that races that disappear before the march of civilisation are mentally unfitted for it. The assumption is not supported by an iota of real evidence. To be mentally incapable a race must be of very defective memory. Recently a school of Australian natives, who belong to one of the “lowest” of races, took the first place in the colony. Negroes occupy a very inferior position in America, especially in Anglo-Saxon territories. But they are stamped by glaring physical differences, are treated with great contempt and jealousy by the whites, and their acquired mental attitudes, therefore, do not develop under good conditions. It is very possible that they are mentally inferior to the whites; but not so inferior as is commonly believed. Russian peasants, though not sharply differentiated by physical peculiarities from the governing classes, are equally scorned by them, and show a mental development hardly, if at all, superior to the negroes of United States. The Latins of South America seem very incapable of orderly government, but they are the heirs of a civilisation older than our own. At any rate, while it is conceivable the American negroes and some other races are incapable of building up a highly-enlightened society by their own efforts, it is manifest that they are able to persist and multiply when civilised conditions are imposed on them. Not so the aborigines of the New World, some of whom--for example, the Maoris and the Polynesians--are admittedly of good mental type. They perish swiftly and helplessly of _bodily_ ailments. Very clearly, then, human races are capable or incapable of civilisation, not because they are mentally, but because they are physically, fit or unfit. G. ARCHDALL REID [Illustration: AN ALPHABET OF RACES BEING A HANDY DICTIONARY OF MANKIND BY W. E. GARRETT FISHER] An attempt is made in these pages to compile a dictionary of the main existing races of the world, arranged in alphabetical order. The accompanying Ethnological Chart on page 352, will enable the reader to see at a glance the relationship of the various main divisions, families, and stocks under which these races are distributed. The Dictionary and the Chart, if used in conjunction, will thus supply information about any race named in the list, and will tell the inquirer to what branch of the human race it belongs. It is obviously impossible to make the Dictionary inclusive of every tiny and out-of-the-way tribe of Africa or South America, but all important races are included. If the reader wants to know something about the Abyssinians, he will look them up in the Dictionary, and find that they are partly Semitic Himyarites, partly Hamitic Gallas, etc. The Chart will then show him that the Hamitic and Semitic families belong to the great Caucasic Division of mankind, that the Himyarites are one of the main stocks of the Semitic family, and that the Gallas belong to the Eastern branch of the Hamitic family. The student should familiarise himself with the names and places of the families and chief stocks of mankind, as given in the Chart, and so greatly facilitate the task of reference. The intention of both Chart and Dictionary is, of course, to serve as a kind of index to the History proper, which must be consulted for further information. As far as can be discovered, no previous attempt has been made to summarise the conclusions of modern ethnology in this convenient form. The illustrations depict some of the most interesting races. =Ababua.= A tribe of Sudanese negroes in Central Africa. See WELLE GROUP. =Abaka.= See NILITIC GROUP. =Abkhasians.= A Western Caucasian tribe occupying the Black Sea coast from Pitzunta to Mingrelia, akin to CIRCASSIANS (_q.v._). =Abo=, or =Ibo=. See NIGERIAN GROUP. =Abors.= An Assamese tribe in the Brahmaputra Valley, belonging to the Tibetan branch of the Southern Mongolic family. Wild jungle-dwellers. =Absarakas.= See SIOUAN. =Abukaya.= A negro tribe in the Sudan. See NILITIC GROUP. =Abunda.= A settled and fairly civilised race of Bantu Negroes, occupying the seaboard and inland districts of Portuguese West Africa, south of Ambriz. =Abyssinians.= A mixed race of Hamitic, Semitic, and Negro stock, inhabiting Abyssinia (from Arabic _habashi_--mixed). The main racial element--Abyssinians proper--consists of brown-skinned Semitic Himyarites, who probably emigrated from Arabia in prehistoric times, and profess themselves descended from the Queen of Sheba. Since the sixteenth century Abyssinia has been over-run by the Hamitic Gallas (_q.v._), who have largely mingled their blood with this older element. There is also a considerable admixture of Sudanese Negro blood. Since the fourth century the religion of Abyssinia has been a corrupt form of Christianity; the mediæval myth of Prester John perhaps relates to this fact. =Acadians.= French settlers of seventeenth century in Nova Scotia. =Achcæans.= See ARGIVES. =Achinese.= A warlike Malay race of Sumatra, long at war with the Dutch colonists. =Accras.= See GA. =Achuas=, or =Wochua=. A pygmy Negrito race, well-proportioned, though dwarfish, inhabiting the forests of the Welle and Aruwimi districts in Central Africa, and living by hunting. =Adamawa Group.= A group of Sudanese Negro tribes inhabiting the district of the Upper Benue in Northern Nigeria. =Adansis.= Negro tribe on Guinea coast. See TSHI. =Æolians.= See HELLENES. =Aetas.= A Negrito race of the Philippine Islands, belonging to the Oceanic family of Ethiopic Man. Short of stature, black-skinned, with woolly hair, they present many points of resemblance to the Negritoes of Central Africa. There are many crosses between Aetas and Malays. =Afars.= A nomadic Turki tribe of Persia. See also DANAKILS. =Afghans.= A race of Iranian stock, belonging to the great Aryan family, who form about half the population of Afghanistan. They are divided into various tribes, of which the Duranis are the dominant one, the Ghilzais the most warlike, and the Yusufzais the most turbulent. There are also large tribes known as Pathans, who are of the same stock as the Afghans, but are classed separately. The Afghans are a handsome and athletic race, inured to war from their childhood, lawless and treacherous, but sober and hardy. Throughout the nineteenth century they were a constant source of trouble to British India, but a new era seems to have opened under the present Amir. For non-Afghan inhabitants of Afghanistan, see HAZARAS, KIZIL-BASHIS, and TAJIKS. =Afridis.= A warlike and turbulent Pathan race, occupying the neighbourhood of the Khyber Pass, and often at war with the English. =Afrikanders.= Persons of European descent born and living in South Africa. =Agaos.= An indigenous Hamitic race of Northern Abyssinia. =Ahoms.= Primitive inhabitants of Assam, belonging to the Indo-Chinese stock of the Southern Mongolic family. =Ainus.= An aberrant family of Caucasic Man in the Far East. They were probably the aboriginal inhabitants of Japan, but are now few in number, and confined to Yezo, the Kurile Islands, and part of Sakhalin. They have regular and often handsome features of Caucasic type, but are of low stature, and characteristically marked by an abundance of coarse, black, wavy or crisp hair on head, face, and body, whence they are commonly called the “Hairy Ainus.” =Akawais.= See CARIBS. =Akkas.= A pygmy Negrito race of the Welle district in Central Africa, akin to the Achuas (_q.v._), who are specially interesting because they are represented on Egyptian monuments of 3400 B.C., with their existing racial characters. =Akkads=, or =Akkadians=. An extinct Mesopotamian race, founders of the oldest known civilisation in Babylonia, who belonged to the Northern Mongolic family, and probably to the Turki or Finno-Ugrian stock. They invented the cuneiform alphabet, which was adopted by their Semitic successors--see BABYLONIANS--and it is thought that they may have been the ancestors of the Chinese. =Akpas.= See NIGERIAN GROUP. =Alani.= A warlike nomadic race, probably belonging to the Turki stock of the Northern Mongolic family, and allied to the Tartars (_q.v._). In the fifth century they made settlements in Gaul and Spain, where they were absorbed by the Vandals and the Visigoths respectively. The remnant left in the East of Europe were conquered in the thirteenth century by the Golden Horde, and their name disappeared from history. =Albanians=, or =Arnauts=. The warlike race of mountaineers who inhabit Albania, on the western coast of the Balkan Peninsula. They are semi-civilised, live in a perpetual state of tribal warfare, and make admirable soldiers, forming the best part of the Turkish Army. They are probably the oldest of the Balkan races, and represent the earliest Aryan immigrants into Europe [see ILLYRIANS]. They are partly Christian, partly Mohammedan. =Albigenses.= A heretical sect, mostly of Provençal descent, who appeared in the South of France about the eleventh century, and were rigidly persecuted until they became extinct in the middle of the thirteenth century. =Alemanni.= An ancient German tribe on Upper Rhine, of Teutonic stock, from whom the modern Swabians and Swiss are in great part descended. =Aleutians.= Natives of Aleutian Islands, belonging to Eskimo stock of Northern American family. =Alfuros.= A half-breed race between Malays and Papuans: in Malaysia, a term given by Malays to their rude non-Mohammedan neighbours. =Algonquian.= A group of North American Indian tribes, formerly inhabiting the Central and Southern States of America, east of the Rocky Mountains, and as far south as South Carolina, now gathered into Indian Reservations. They include the Algonquin, Blackfoot, Cheyenne, Cree, Delaware, Fox, Illinois, Massachusett, Mohican, Ojibway, Sac, Shawnee, and many smaller tribes. =Alibamus.= See MUSKHOGEAN. =Ali-Elis.= See TURKOMANS. =Alsatians.= Natives of Alsace, of High German stock, allied to the Swabians (_q.v._). =Amadis.= See WELLE GROUP. =Ama.= Prefix of many Bantu racial names, as Ama-Zulu, Ama-Xosa. See ZULU, etc. =American.= One of the four main divisions of the human race, comprising three families, occupying North, Central, and Southern America respectively. Typically red-skinned, with lank, black hair, retreating foreheads, high-bridged noses, and either long or broad skulls--dolichocephalic or brachycephalic. =Americans.= The English-speaking white inhabitants of the United States, mainly of Anglo-Saxon descent. See also LATIN AMERICANS. =Amharas.= Natives of Central Abyssinia, of Hamitic descent. =Amorites.= A branch of the ancient Libyan race, of Semitic origin, inhabiting Canaan before the arrival of the Israelites from Egypt. =Anatolian Turks.= See TURKS. =Andamanese.= Natives of Andaman Islands, a race belonging to the Oceanic Negrito family, possibly representing the primitive type from which both Negroes and Papuans have sprung. They exhibit the lowest stage of civilisation. =Andis.= See LESGHIANS. =Angles.= A Teutonic race of Low German stock, who formerly inhabited the country round Schleswig, in North Germany. In the fifth century they migrated in large numbers to Britain, and with the Jutes and Saxons formed the stock of the Anglo-Saxon or English people. =Anglo-Saxons.= A general name now given to the English-speaking races of English, Scotch, and even Irish and Welsh descent, who inhabit the British Empire; in a wider sense, to all people of British descent. =Annamese.= Natives of Annam, or Cochin-China, belonging to the Indo-Chinese stock of the Southern Mongolic family; now under French rule. =Apaches.= See ATHABASCAN. =Appalachis.= See MUSKHOGEAN. =Arabs.= One of the main branches of the Semitic family, inhabiting the Arabian peninsula. They are usually divided into two branches, the Ishmaelites of the north and the Joktanides of the south. The latter probably represent the oldest Arab stock, and may be of African origin. The primitive Arabs were nomadic horse-breeders and shepherds, very warlike, and of fine physical development. Under Islam they reared an enduring religious civilisation, which has had the greatest influence on the world after Christianity. =Arakanese.= Natives of Arakan, in Lower Burma, of Indo-Chinese stock. =Aramæans.= One of the main groups of the Semitic family, Syro-Chaldeans, who anciently inhabited Syria, Palestine, and the Euphrates Valley. The modern Syrians (_q.v._) belong to it. [Illustration: A LITTLE GALLERY OF RACES REPRODUCED FROM THE FAMOUS DRAWINGS BY SIR DAVID WILKIE, R.A.] [Illustration: A NATIVE OF BRITISH INDIA] [Illustration: A CIRCASSIAN LADY] [Illustration: A SPANISH CHILD WITH HER NURSE] [Illustration: A PERSIAN PRINCE AND HIS NUBIAN SLAVE] [Illustration: A DRAGOMAN AT BEYROUT] [Illustration: A TRAVELLING TARTAR] [Illustration: AN ARAB SHEIK] [Illustration: A LETTER-WRITER OF CONSTANTINOPLE] =Araucanians.= The chief Indian race of Chili, possessing an ancient civilisation like those of Peru and Mexico, though less advanced. The Araucanians are probably the finest native race of the New World. They are a fierce and warlike people, who have always preserved their independence. =Arawaks.= A group of South American Indian tribes in the Guianas, including Maypuris, Wapisianas, Atorais and others. =Arcadians.= A race of ancient Greece, inhabiting the central highlands of the Peloponnesus, whose seclusion from the world caused them to be identified with the quality which we still call Arcadian simplicity. =Arecunas.= See CARIBS. =Argentines.= White natives of the Argentine Republic in South America, mainly of Spanish descent. =Argives.= Natives of Argos, the most important state of Homeric Greece: hence a generic term for Greeks or Hellenes in the Homeric Age. Achæans is another term similarly used. =Armenians.= Natives of Armenia, the mountainous country round Mount Ararat, now divided between Russia, Persia, and Turkey. They belong to the Iranian stock of the Aryan family, blended with Semitic blood, and with a still older unknown but probably non-Aryan element. They are not warlike, but of quick intelligence and specially successful in commerce. =Arnauts.= See ALBANIANS. =Aryans.= The most important family of Caucasic Man, to which all the chief civilisations of modern times belong. A tall, fair-skinned, long-headed race, whose origin is still doubtful--though it was probably in Central Asia--and who spread in prehistoric times over the whole of Europe and parts of Asia and Africa. Almost all modern Europeans are of Aryan descent. The family is also called INDO-EUROPEAN or INDO-GERMANIC, but these names are open to objections from which the term Aryan is free. =Ashantis.= See TSHI. =Assamese.= Natives of Assam, between India and Burma, belonging to the Hindu stock of the Aryan family. =Assinaboins.= See SIOUAN. =Assyrians.= One of the main branches of the Semitic family. The Assyrians founded a great empire in the northern part of Mesopotamia, of which Nineveh was the capital, and afterwards conquered the older Babylonian state (710 B.C.) and Egypt (671 B.C.), thus forming the first world-empire known to history. Within a century Assyria had become a Median province, and its people ceased to have an independent existence. =Athabascan= or =Tinney=. A group of North American Indian tribes, formerly inhabiting Alaska and the greatest part of Canada. It includes the Apaches, Chippewayans, Hupas, Kutchins, Navajos, Tacullis, and Umbquas. =Athenians.= The most important race of ancient Greece, whose city of Athens was the earliest centre of civilisation in the historical age of Europe. =Australians.= The aborigines of Australia, a branch of the Oceanic Negro family. Their numerous tribes present a general uniformity of physical and mental development, under which two main types may be recognised. The earlier of these is probably that shown by the extinct Tasmanians (_q.v._), one of the lowest races in point of culture yet discovered, who were probably still in the earliest stage of the Stone Age. The other type was perhaps akin to the Dravidians of India, or to a very low Caucasic race. The Australians are among the lowest of savage races, and present many features which have thrown light on the manners, customs and beliefs of primitive man. =Australians.= White inhabitants of Australia, mostly of Anglo-Saxon descent. =Austrians.= Inhabitants of the Austrian empire, including a great diversity of races. The name is properly applied only to the German-speaking people, of High-German Teutonic stock, who predominate in Austria proper. =Auvergnats.= Natives of Auvergne, in Central France. A short, sturdy, dark, round-skulled race, formerly regarded as typical Aryan Celts, but possibly descended from an older non-Aryan people. Much employed in Paris as porters. =Avars.= See LESGHIANS. =Avars.= A Tartar tribe, belonging to the Turki stock of the Northern Mongolic family, who appeared in the district round the Caspian Sea about the fourth century, and later made predatory raids over a large part of Eastern Europe. They were subdued by Charlemagne, and disappeared from history in the ninth century. They seem to have been closely allied to the Huns, whom they resembled in physical characteristics and warlike qualities. =Awawandias.= Bantu Negroes of the Nyassa plateau in British Central Africa. =Aymaras.= A race of South American Indians in Bolivia, probably related to the Incas (_q.v._) and perhaps their ancestors. =Azandeh=, or =Niam-Niam=. Sudanese Negroes of the Welle group. Notorious cannibals. =Aztecs.= The dominant Indian race in Mexico at the arrival of the Spanish invaders. They entered the country about the end of the thirteenth century, and founded the city of Mexico in 1325. Around it they reared a remarkable civilisation and a sanguinary religion. They were warlike, ferocious and cruel, but had a considerable aptitude for the arts of peace. Their empire was destroyed by Cortes in 1521, and annexed to Spain. Every trace of Aztec nationality was suppressed, but their name still lingers among the Nahuan Indians, and their blood is mixed with that of the conquerors. Many attempts have been made to find an Old World origin for Mexican culture, but they are not convincing. =Babylonians.= The Semitic race which founded one of the greatest of ancient civilisations in the rich alluvial plains of Chaldæa and on the arid plateau of Mesopotamia. Their history is too long to summarise here, but it may be stated that the Semitic peoples, variously known as Babylonians, Chaldæans, Elamites, Medians, and Assyrians, invaded and dispossessed at different times the primitive Mongolic race of Akkads (_q.v._). Their earliest settlement seems to have been at Ur of the Chaldees, on the right bank of the Euphrates. Babylon and Nineveh were afterwards the seats of the Babylonian and Assyrian powers, whilst Elamite and Median conquerors intervened at various times. These powerful Semitic races made great advances in art, science, literature, religion, and social policy. Their first incursion, probably from Arabia, into the Euphrates Valley dates back to about 3800 B.C. =Baggaras.= A fierce and warlike race settled in the Anglo-Egyptian Sudan, and formerly dominant under the Mahdi. =Baghirmis.= See LAKE CHAD GROUP. =Bakairi.= See CARIBS. =Bakatla=, =Bakwena=. Bantu Negroes of Bechuana stock. =Bakwiri.= Bantu Negroes settled in the Cameroons. =Balinese.= A Malayan race of the East Indian Archipelago. =Balolo.= Bantu Negroes of the Middle Congo; one of the finest negro races. =Balong.= Bantu Negroes of West Africa. =Baltis.= A hardy Tibetan race, inhabiting the Alpine valley of the Upper Indus. =Baluba=, or =Basonge=. A dominant Bantu Negro race of the Kassai basin in Equatorial Africa. =Baluchis=, or =Beluchis=. Natives of Baluchistan, south of Afghanistan, of Iranian (Aryan) descent, with a mingling of Tartar (Mongolic) blood. The dominant race of the country is the Brahui, aboriginals who are probably of Mongolic descent, allied to the Dravidians (_q.v._) of India. The Brahui are of Mongolic type, short, with round flat faces, hospitable and generous. They are the more settled portion of the inhabitants. The Baluchis are chiefly nomads, taller, with more Aryan features, a warlike and predatory people. =Balunda.= Bantu Negroes of South Central Africa, occupying the Congo-Zambesi divide. =Bamangwato.= Bantu Negroes of north Bechuanaland; Khama’s semi-civilised people. =Bambaras.= See MANDINGAN. =Banandi.= Bantu Negroes of apish type, in the Semliki forests. =Bangalas.= Bantu Negroes of Middle Congo, on the Ubangi river. =Bantus.= One of the two subdivisions of the African Negro family of Ethiopic Man, occupying the southern half of the African continent, south of the Cameroons and Albert Nyanza. A Negro race modified from the Sudanese type by Hamite influences. =Banyai.= Bantu Negroes, south of the Middle Zambesi. =Banyoro.= See WANYORO. =Bapedi.= Bantu Negroes of Bechuana stock. =Bareas.= Sudanese Negroes inhabiting the Abyssinian slopes. =Barguzins.= See BURIATS. =Baris.= See NILITIC GROUP. =Barolongs.= Bantu Negroes of Bechuana stock, between Vryburg and Molopo river. Mafeking is their capital. =Barotse.= Bantu Negroes of Bechuana stock, about headwaters of Molopo river. =Barrés.= South American Indians in Venezuela and Guiana. =Basés.= Sudanese Negroes of Abyssinian slopes, a very low negroid type. =Bashkirs.= A branch of the Turki stock of the Northern Mongolic family. They are first mentioned in the tenth century as a warlike and idolatrous race, noted for their large, round, short heads, from which their name is derived. They now inhabit the Orenberg and Perm districts of Russia, on the western slopes of the Ural. Some are settled agriculturists, others pastoral nomads. =Bashukulumbwe.= Bantu Negroes of Kafue basin in Zambesia. =Basimba= or =Cimbebas=. Aboriginal Negroes of South Angola; a low Bantu type, or possibly Negrito, allied to Bushmen. =Basonge.= See BALUBA. =Basques.= One of the few non-Aryan races still existing in Europe, where they inhabit the districts on the French and Spanish sides of the Western Pyrenees. They originally occupied a much wider area in this neighbourhood, and preserve their ancient costume and language. Their ethnological affinities are still in dispute, but the best opinion is that they represent the ancient Iberians (_q.v._), a Western Hamitic race, related to the Berbers of North Africa on the one hand and to the Picts of Scotland and the ancient Irish on the other. Probably they have occupied their present home since Neolithic times. They are mainly agriculturists, with all the rustic virtues, and make excellent soldiers and servants. =Bassas.= See LIBERIAN GROUP. =Bastaards.= See GRIQUAS. =Bastarnæ.= See GOTHS. =Basutos.= The most civilised race of Bantu Negroes, of the Bechuana stock, who inhabit the rugged uplands of Basutoland, a British Crown Colony. They have long been subjected to European and Christian influence, under which they have presented the sole instance of a pure negro community, which has made itself self-supporting and approximately civilised. They have succeeded in assimilating Western culture, and their little State--which always preserved its independence against other natives and Boers--is a very flourishing example of what the negro can do under favourable auspices. =Batanga.= Bantu Negroes of the Cameroons. =Batavi.= An ancient German race inhabiting the island formed by the Meuse and an arm of the Rhine. Ancestors of the modern Dutch. =Bateke.= Bantu Negroes of Congo, above Stanley Pool. =Batjans.= See INDONESIAN. =Batlapi.= Bantu Negroes of Bechuana stock, near Vryburg. =Batonga= or =Batoka=. Bantu Negroes of Zambesia, Manicaland and Tongaland. =Battaks.= A pre-Malay race of North Sumatra, probably allied to the Polynesians (_q.v._). =Batwas.= A pygmy (_q.v._) Negrito race south of Congo, allied to Bushmen. =Batwanas.= Bantu Negroes of North Bechuanaland. =Bavarians.= A branch of the High German stock of the Teutonic family, in Bavaria. =Bayansis.= Bantu Negroes of Middle Congo, on Kwa River. Strong negro element. =Bechuanas.= A main stock of Bantu Negroes, occupying what is known as British Bechuanaland. The name is of European origin, and has no native significance as applied to the race, but is a convenient general term. =Bedawi= or =Bedouins=. Nomadic Arabs (_q.v._) who inhabit the deserts of Arabia and the neighbouring countries, and live by stock-breeding and robbery. Their breed of horses is world-famous. They are independent, chivalrous and hospitable. They correspond to the Biblical Ishmaelites, whose race and customs they preserve practically unchanged. =Bejas.= A race of Eastern Hamites, of splendid physique, occupying the eastern seaboard of Africa north of Massowah, including Bisharis, Hadendowas, and other tribes. =Belgae.= The northernmost of the three races occupying Gaul in Cæsar’s time, probably of Low German stock, with perhaps a Celtic element. =Belgians.= The inhabitants of Belgium, formerly the Spanish or Austrian Netherlands, of very mixed origin. The natives are either Flemings of Teutonic stock, or Celtic Walloons (_q.v._). Mingled with these are large numbers of German, French and Dutch immigrants; and constant crossing of blood has tended to produce a truly Belgian type out of all these fluctuating elements. They are among the most patient and productive of agriculturists, mostly small proprietors; and they possess flourishing manufactures and a rich commerce through the great port of Antwerp. =Beluchis.= See BALUCHIS. =Bengalis.= The majority of the natives of Bengal belong to the Hindu stock of the Aryan family, which was probably the first to develop a true civilisation and a great literature (in the ancient Sanscrit tongue). The typical Bengali is quick-witted, versatile, and successful in the arts of peace, but not warlike--though the native army of the old East Indian Company was largely recruited from Bengal. The Bengali Babu, of the professional or lower official class, is well known. =Beluchis.= See BALUCHIS. =Benin.= See NIGERIAN GROUP. =Berbers.= A Western Hamitic race occupying the Atlas Mountains and the Northern Sahara, of predatory and warlike habits. They are known in Algeria as Kabyles, and in Sahara as Tuaregs. Largely dark-haired and swarthy, with prominent noses, they belong to the Melanochroid branch of Caucasic Man. They correspond to the ancient Numidians. =Betsimisarakas.= One of the three main divisions of the Malagasy, or Malayo-African race which inhabits Madagascar. They occupy the east coast. =Bhils.= Primitive and still wild non-Aryan inhabitants of Central India, of Kolarian family (_q.v._). =Bisharis.= See BEJAS. =Blackfoot Indians.= See ALGONQUIAN. =Bœotians.= A branch of the Æolian race in ancient Greece. The Bœotians were supposed to be peculiarly dull, and were the typical rustic clowns of Greek literature. =Boers.= White inhabitants of Cape Colony, the Transvaal, and the Orange River Colony, mainly of Dutch descent, with a French Huguenot element and a sprinkling of Negro blood. They were the original colonists of South Africa, which they entered in 1652. A race of farmers (Boer is derived from the Dutch boor, peasant), they also proved themselves to be hardy pioneers and admirable, though not at all romantic, fighters, learning in long native wars the arts of strategy, which they exercised so well against the English in the South African War of 1899-1902. They have now accepted the English rule, and promise to be among our most flourishing African subjects. =Bohemians.= See CZECH. =Bolivians.= White natives of Bolivia in South America, of Spanish descent, with a considerable admixture of Indian blood. =Bongos.= See NILITIC GROUP. =Botocudos.= South American Indians on eastern seaboard of Brazil. =Brahui.= See BALUCHIS. =Brazilians.= White natives of Brazil, mainly of Portuguese descent, but with a considerable admixture, in many districts, of Indian and negro blood. =Bretons.= Natives of Brittany, descended from a short, round-headed, dark race, generally called Celtic, but perhaps pre-Aryan. =Bribris.= South American Indians of Costa Rica. =Britons.= (1) The ancient Britons were a Celtic race, whose remnants are still to be found in the Welsh (_q.v._). They attained a considerable degree of civilisation under the Roman conquerors, and adopted Christianity. The Anglo-Saxon conquest of Britain drove most of them back into Wales, Cornwall, and other outlying portions of the island, whilst the remainder were either destroyed or assimilated. (2) In the wide modern sense, Britons are the white citizens of the British Empire. =Bugis= or =Buginese=. Natives of Boni in Celebes; a primitive Malay race. =Bulalas.= See LAKE CHAD GROUP. =Bulgars.= A branch of the Finns (_q.v._), who were originally settled on the banks of the Volga. In the sixth century they crossed the Danube and conquered the modern Bulgaria, then occupied by the Slavonic Slovenians (_q.v._). A speedy fusion took place between the Slovenians and the Bulgars, who adopted the language and customs of the former, and rose to greatness as a Slav power. In the ninth and tenth centuries they ruled the greater part of the Balkan Peninsula, and warred successfully with the Byzantine Empire, which, however, subjected them in 1019 under Basil II., “the slayer of the Bulgarians.” Later they passed under the Turkish rule, and ceased to have an independent national existence down to the nineteenth century. =Bulgarians.= Inhabitants of the modern Balkan state of Bulgaria, descended from the Bulgars (_q.v._) with considerable admixtures of Greek and Turkish blood. =Bulloms.= See TEMNÉ GROUP. =Burgundians.= An ancient people of Teutonic race (High German), who were originally settled between the Oder and Vistula. In the fifth century they invaded Gaul, where they formed the first kingdom of Burgundy, between the Aar and the Rhone. There were many later Burgundian kingdoms and duchies, of which the last and most famous was that of Charles the Bold, annexed to France in 1477. The Burgundians are now French subjects, but still show traces of their Teutonic origin. =Buriats.= The Western or Siberian branch of the Mongol stock of the Northern Mongolic family. They occupy the vicinity of Lake Baikal The majority are nomad pastors, but some have taken to agriculture. A peace-loving, but lazy and drunken people; they include various tribes, such as the Barguzins, Selengese, Idinese, Kudaras and Olkhonese. =Burmese=, or =Burmans=. A short-statured, thick-set and flat-featured people, approaching the Chinese type, the principal race of the Indo-Chinese stock of the Southern Mongolic family. They inhabit Burma--now a British possession--and are excitable, turbulent, and given to dacoity, or highway robbery. They make good farmers and shopkeepers, but are not warlike or methodical. =Burus.= See INDONESIANS. =Bushmen.= A nomadic Negro race of South Africa, who stand at the lowest stage of human culture. They are probably the aborigines of South Africa, where they have been dispossessed by Hottentots and Bantus from the north. They are thin and wiry, of small stature, not unlike the Hottentots in colour and features. They live by hunting, and possess a curious mythology. Their artistic powers, comparable to those of Palæolithic Man, are shown in the remarkable rock-drawings on the walls of their caves. =Calchaquis.= South American Indians, in Plate River district. =Cambojans.= Natives of Cambodia, Mongoloid approaching Caucasic type. =Canaanites.= One of the main branches of the great Semitic family, inhabiting Palestine and the Mauritanian sea-coast in ancient times, including Jews, Phœnicians, Carthaginians, Moabites, Amorites, Idumæans and Philistines (_q.v._). A fierce and warlike people, with a remarkable genius for religion, which has greatly influenced the modern world. =Canadians.= White natives of Canada, of mixed French and Anglo-Saxon descent. =Caribs.= South American Indians, formerly occupying the West Indian Islands, and now the shores of the Caribbean Sea, including Macusi, Bakairi, Akawai, Arecuna, and Rucuyenne tribes. They are strongly built, warlike and fierce, but honourable. The term cannibal is supposed to be a corruption of their name based on their habits. =Carthaginians.= Natives of one of the great empires of the ancient world, which was founded at Carthage, near the modern Bizerta, by Phœnician colonists in the ninth century B.C., and was destroyed by Rome in 146 B.C. Carthage was the great rival of Rome as a Mediterranean power. Its inhabitants belonged to the Canaanite stock of the Semitic family, and were a nation of traders, cruel and gloomy in temperament, worshippers of Moloch with human sacrifices. Though in Hannibal they produced one of the greatest of generals, they were not warlike, and trusted chiefly to mercenaries, wherefore they fell. =Catalans.= Natives of North-east Spain, mostly of Gothic descent, and still distinct from other Spaniards in language and costume. Honest and enterprising, turbulent, and intensely devoted to liberty. =Caucasians.= One of the families of Caucasic Man, inhabiting the mountainous region of the Caucasus, and divided into southern, western, and eastern branches [see GEORGIANS, CIRCASSIANS, CHECHENZES, LESGHIANS]. They include a great number of different tribes, who seem to have settled there from the earliest historical times. Some of these, the Melanochroid highlanders, like the Georgians, Circassians, and Lesghians, present an almost ideal standard of physical beauty, whilst others are squat and ungainly. Some ethnologists see in the Caucasus the primitive home of the Aryan family, from whom the Caucasians would, on this view, be an offshoot. The Ossets (_q.v._) are certainly Aryan. The Caucasians are very warlike, and struggled till quite recently with success against the Russian domination. =Caucasic.= One of the four great divisions of the human race. Type, white-skinned, square-jawed (orthognathous), skull between broad and long (mesocephalic), hair soft, straight, or wavy; in intelligence, enterprise, and civilisation, much superior to other divisions. =Cayugas.= See IROQUOIAN. =Celts.= See KELTS. =Chakhars.= A branch of Eastern Mongols, settled on the south-east boundary of the Desert of Gobi. =Chaldæans.= See BABYLONIANS. =Chamorros.= Aborigines of the Ladrone Islands, so named from their thievish propensities. A branch of the Oceanic Mongolic family, probably allied to the Formosans (_q.v._). =Chancas.= See INCAS. =Chaudors.= A nomad tribe inhabiting the steppes east of the Caspian and south of the Oxus. See TURKOMANS. =Chapogirs.= See TUNGUSES. =Charruas.= An extinct race of South American Indians in South Brazil, peculiar for their extremely black colour with lank hair. =Chechenzes.= A branch of the Eastern stock of the Caucasian family, inhabiting the northern slopes of the Eastern Caucasus. Their chief tribes are Ingushis, Kishis, and Tushis. =Cheremisses.= See FINNS. =Cherokees.= A brave and warlike tribe of North American Indians. See IROQUOIAN. =Cheyennes.= See ALGONQUIAN. =Chibchas.= South American Indians of Bogota. =Chichimecs.= See NAHUANS. =Chickasaws.= See MUSKHOGEANS. =Chilians.= White natives of Chili, of Spanish descent, with a mixture of Araucanian Indian blood. =Chinese.= One of the most numerous races of the world, inhabiting the Chinese Empire. They are a stock of the Southern Mongolic family, and it is thought by some ethnologists that they are descended from the Mongolic Akkads (_q.v._) of Mesopotamia. There is a remarkable uniformity in the physical type presented by the Chinese in all climates and environments; they are the most homogeneous of great peoples. They are yellow-skinned, short in stature, with obliquely set eyes, high cheek-bones, long skulls, and broad faces, with slight prognathism. They possess an ancient and highly organised civilisation, which is characterised by its conservatism and slowness to accept new ideas--so different in this from the Japanese. The Chinese are naturally frugal, industrious, and patient; they are excellent agriculturists, and very gregarious; they despise war, but make excellent soldiers when drilled by Europeans or Japanese. They are eminently literary, and have a high system of morality. There are many local varieties, such as the Puntis of the Canton districts, the Hakkas of Swatow, the Hoklas of Fohkien, the Dungans (_q.v._), which need not be farther particularised. =Chinooks.= A nearly extinct tribe of North American Indians on the Columbia River, on whose language is based the Chinook jargon, or traders’ Lingua Franca of British Columbia. =Chins.= See SINGPHOS. =Chippewayans.= See ATHABASCAN. =Chiquitos.= South American Indians of Upper Paraguay basin. =Chiriguanos.= South American Indians of Bolivia. =Chitralis.= Natives of Chitral, in the Hindu Khush, rough, hardy hillmen, closely allied to the Kafirs (_q.v._) of Kafiristan. =Chocos.= A tribe of South American Indians of Matto Grosso. =Choktaws.= See MUSKHOGEAN. =Chontals.= Central American Indians of Nicaragua. =Chols.= See MAYA-QUICHÉ. =Chorasses.= See KALMUKS. =Chorotegans.= Central American Indians of Nicaragua. =Chukchis.= A Northern Mongolic race of North-east Siberia, closely akin to the American Eskimo in features and customs. They are of high character and very independent, but at a low stage of civilisation, and live by reindeer-breeding and hunting. A branch of the Chukchis, differing mainly in language, is known as the Koryaks. =Chunchos.= South American Indians on tributaries of Beni River in Peru. =Cimbebas.= See BASIMBA. =Circassians=, or =Tcherkesses=. A race of Caucasian mountaineers, formerly inhabiting the Black Sea coast between Anapa and Pitzunta, of high physical type, who maintained an unavailing struggle against Russia till 1864, when their subjugation was followed by a wholesale emigration of the Circassian tribes to the Turkish Empire. Allied to them are the Abkhasians and Kabards (_q.v._). =Colombians.= White natives of Colombia, in Central America, mostly of Spanish descent, with an admixture of Indian and negro blood. =Comanches.= See SHOSHONEAN. =Conibos.= South American Indians of Peru. =Copts.= Christian descendants of the ancient Egyptians (_q.v._), of middle stature, slender limbs, and pale complexion, who inhabit Egypt, and preserve the language and customs of the last period of ancient Egyptian civilisation. They are essentially townsmen, clerks, or artisans. =Coras.= See OPATA-PIMA. =Cornish.= A race of Brythonic or P Celts, akin to Welsh and Bretons, inhabiting Cornwall in earlier times; now absorbed in English stock. Their language became extinct in seventeenth or eighteenth century. The crossing of the Cornish Celts with Anglo-Saxons has given birth to a singularly fine race of hardy fishermen and miners. =Corsicans.= The aborigines of Corsica were probably a Western Hamitic race, allied to the Ligurians (_q.v._). They were followed by Ionian invaders, and in turn by Carthaginian, Roman, Vandal, Hun, Gothic, Saracenic, and Italian conquerors, each of whom has added something to the mixture of blood in the modern Corsicans, a turbulent, lawless, and warlike race (now belonging to France), whose greatest son was Napoleon. =Costa Ricans.= White natives of Costa Rica, in Central America, mostly of pure Spanish descent. =Crees.= See ALGONQUIAN. =Creek Indians.= See MUSKHOGEAN. =Creoles.= Persons born in past or present French, Spanish, or Portuguese colonies, of pure European descent. =Cretans.= An ancient race of prehistoric culture [see MYCENÆANS]; in modern times chiefly Greek, mixed with Turk. =Croats.= Inhabitants of Croatia, now mainly of Slavonic race, mingled with an earlier short, dark race of non-Aryan descent. One of the motley races of the Austrian Empire. They are warlike, turbulent, and eager for independence. =Cro-Magnon.= A prehistoric race settled in the Vezere district of France, which may be taken as the primitive type of Caucasic Man. It is only known by a few skulls and other relics, and probably dates back to the Glacial Period. =Crow Indians.= See SIOUAN. =Cymry.= See WELSH. =Czechs=, or =Bohemians=. The most westerly branch of the Slavonic stock of the Aryan family, now occupying Bohemia, Moravia, and other parts of Austria. They are closely allied to the Slovaks of Hungary. They migrated from the Upper Vistula district to the modern Bohemia in the fifth century. Long an independent kingdom, and a bulwark of Christendom against the Turks, Bohemia passed to Austria in 1526. During the last century there has been a great recrudescence of the Czech nationality and language. The Czechs as a race are very musical and artistic. =Daflas.= A Tibetan race inhabiting the northern border of Assam. =Dahomans.= See EWE. =Dakotas.= See SIOUAN. =Dalmatians.= A Southern Slavonic race, crossed with Gothic blood. A fine race of hardy seamen, they manned the Venetian fleets, but now belong to Austria. =Damaras=, or =Hau-Khoin=. See HEREROS. =Danakils=, or =Afars=. An Eastern Hamitic race settled in the vicinity of Obock, between Abyssinia and the Red Sea. They are nomad pastors and fishermen, well-built, and slender. =Danes.= Natives of Denmark, belonging to the Scandinavian stock of the Aryan family. Denmark was originally inhabited by the Angles, Saxons, and Jutes, who colonised England. On their departure, the Danes from Zealand settled on the deserted lands, and there reared the kingdom which still exists. The early Danes were brave warriors and skilled seamen, who for a time ruled Saxon England under Canute. Their descendants, of comparatively pure blood, preserve these characteristics, and are also industrious agriculturists. =Dards.= A warlike and hardy race of Aryan descent, inhabiting the mountainous country around Gilgit, in North-west India, of whom the Hunzas and Nagars are the chief tribes. =Dargos.= See LESGHIANS. =Delawares.= A North American Indian race with whom William Penn dealt in the 17th century: now fairly civilised. See ALGONQUIAN. =Didos.= See LESGHIANS. =Dinkas.= See NILITIC GROUP. =Dogras.= An Aryan race in the Punjab, between the Chinab and the Ravi, who contribute excellent soldiers to the British Native Army. =Dorians.= See HELLENES. =Dravidas=, or =Dravidians=. Indigenous non-Aryan inhabitants of South India, including the Telingas or Telugu of the Nizam’s Dominions, the Tamils of Karnatic and Ceylon, the Kanarese of Mysore, the Malayalim of Malabar Coast, those wild hunters the Gonds of Vindhya Hills, the Sinhalese of Ceylon, and perhaps the Veddahs (_q.v._). A Mongoloid race originally, which has been assimilated to the Caucasic type by long intermixture of blood. =Druses.= A brave, handsome and industrious white race, who have been settled in the Lebanon district of Syria for at least 800 years, and owe their unity to the possession of a special religion. Their origin is uncertain, but they are probably of a mixed stock, to which Arabs, Kurds, and Persians have all contributed. They are fair-haired and of light complexion. They are very warlike, have always preserved their independence against the Turks, and are the inveterate enemies of the Maronites (_q.v._). =Dungans.= Southern Mongolic inhabitants of Zungaria, between Tian-Shan and Altai. Allied to Chinese (_q.v._). =Durbats.= See KALMUKS. =Duranis.= See AFGHANS. =Dyaks.= The aborigines of Borneo, probably akin to the Malays (_q.v._), whom they resemble physically, though of greater average stature. They are active and warlike, and formerly indulged in the practice of head-hunting, now dying out. The Sea-Dyaks were bold and inveterate pirates. They possess a considerable degree of indigenous civilisation, and their moral character is very fine. =Easter Islanders.= (1) See POLYNESIANS. (2) Easter Island once possessed an older race of inhabitants, now extinct, who have left very remarkable traces in the shape of numerous colossal statues, thin-lipped and disdainful, standing on platforms of Cyclopean masonry, as well as many stone houses with thick walls, painted on the inside. Nothing farther is known of their race or history. =Ecuadorians.= White natives of Ecuador, in South America, of Spanish descent; noted for their laziness and political instability. =Edomites.= See IDUMÆANS. =Egbas.= See YORUBAS. =Egyptians.= (1) The ancient inhabitants of Egypt--known to them as Khem, the Biblical Mizraim--who reared one of the oldest and most important civilised states of the ancient world. The aborigines of Egypt were apparently a Palæolithic branch of Ethiopic Man, allied to the modern Bushmen. They were dispossessed and practically exterminated, probably about 7000 B.C., by a slender, fair-skinned race of European type, belonging to the Hamitic family, and resembling the modern Berbers (_q.v._) in many respects. These were probably the same as the ancient Libyans (_q.v._). Later this race was modified by the introduction of a Semitic element, partly from Syria, partly from the Phœnician conquerors who founded dynastic rule in Egypt under Menes, between 5000 and 4000 B.C. Their later history is written on their imperishable monuments, and need not be summarised here. In later times the Egyptian racial type was modified by Greek and Roman influence. The ancient Egyptians were highly skilled in agriculture and engineering, warlike but not aggressive, and with a highly developed literature and religion. (2) The modern Egyptians are partly descended from the ancient Egyptians, whose racial type as represented on the monuments is still to be found in purity, mingled with Bedouin Arabs, Turks, Syrians, and other races. See COPTS and FELLAHIN. =English.= Natives of England; used in a wider sense as equivalent to citizens of the British Empire [See BRITONS, ANGLO-SAXONS]. The English people are a Low German branch of the Teutonic stock of the Aryan family, with a faint Celtic element derived from the primitive Britons, a strong Scandinavian element (especially in the north-east), derived from the invading Danes and Norsemen in the ninth to eleventh centuries, and a considerable Norman element--Norse modified by French culture. The typical Englishman is white-skinned and fair-haired, belonging to the Xanthochroi, but there are many deviations due to modifying influences. The race is eminently warlike and aggressive, and makes the most successful colonisers known to the world. =Erie Indians.= See IROQUOIAN. =Erse.= See IRISH. =Eshi-Kongo.= A semi-civilised race of Bantu Negroes, belonging to the ancient Kongo Empire, now Portuguese West Africa. =Eskimos=, or =Innuits=. An Arctic aboriginal race, now inhabiting Greenland and the northern coasts of the American continent. They are nomadic, live by hunting and fishing, and are inured to extremes of cold. They are very broad-headed, fat, and of short stature, with flat quasi-Mongolic features. They seem to occupy a place midway between the North American Indian and the Mongolic type, and there is some reason to suppose that they represent a prehistoric Mongoloid incursion from Northern Asia, or perhaps from Indo-Malaysia. =Esthonians.= A branch of Baltic Finns (_q.v._) settled in Esthonia, and possessing an ancient ballad literature and mythology. =Ethiopians.= An ancient Berber tribe, settled in Egypt at least 5,000 years ago, now represented by the fair Berbers of Mauritania. Homer called them “blameless,” because he knew so little about them. See NUBIANS. =Ethiopic.= One of the four great divisions of the human race, occupying Africa, Australia, and many islands of the Eastern Ocean. Its members are typically black-skinned and woolly haired, with projecting jaws and broad skulls. =Etruscans.= An ancient Italian people, inhabiting Etruria in North Italy in pre-Roman times. They probably consisted of an aboriginal Pelasgian (_q.v._) race, modified by a dominant race of invaders, who may have been of Mongolic type, or perhaps akin to the Hittites (_q.v._). The Etruscans may be classed as Hamitic. They had a distinctive civilisation, and made great progress in art, of which many monuments remain. The Etruscan confederation, of which Veii was the chief city, long warred with the rising power of Rome, under whose dominion it fell in the fourth century B.C. Families of undoubted Etruscan descent are still found in North Italy. =Europeans.= Natives of Europe, mainly Aryan. =Ewe.= A group of Sudanese Negro tribes of Guinea Coast. The best known are the Dahomans, or natives of the ancient kingdom of Dahomey, on the Slave Coast. Of small stature, but robust and warlike, they are noted for their great human sacrifices and their employment of female warriors or “Amazons.” Now under French rule. The Togos are also an Ewe tribe. [Illustration: AN ARAB VILLAGE ON THE BORDERS OF EGYPT] =Fans.= A race of powerful and aggressive warriors, who intruded into Gaboon-Ogoway district about the middle of the nineteenth century; possibly related to Azandeh or Fulahs (_q.v._). Cannibals, but otherwise of higher intellect and morality than the average Negro, from whom they differ in physical type. =Fantis.= See TSHI. =Fellahin.= The labouring peasantry of modern Egypt, industrious but not warlike, descendants of ancient Egyptians, with a mixture of Syrian and Arab blood. =Felup.= A group of Sudanese Negro tribes on Casamanza and Cacheo estuaries. =Fertits.= See NILITIC GROUP. =Fijians.= Natives of Fiji, belonging to the Melanesian stock of the Oceanic Negro family. Formerly ferocious cannibals, they are now civilised. =Filipinos.= See PHILIPPINES. =Fingus=, or =Ama-Fingu=. Bantu Negroes of the Kafir division in South-east Africa, regarded by Zulus and Ama-Xosa as an inferior race. =Finno-Ugrian.= A stock of the Northern Mongolic family, including (1) Ugrian or Siberian Finns, of which the chief races are Soyots, Ostyaks, Samoyedes, Voguls, Permian Finns, Siryanians, and Magyars (_q.v._); (2) European Finns, divided into: (_a_) Volga Finns, (_b_) Baltic Finns. =Finns.= The Finns proper are the inhabitants of Finland, between Russia and Norway. They are a Northern Mongolic race, of Finno-Ugrian stock, who are supposed to have originated beside the head waters of the Yenisei River. They entered Finland about the end of the seventh century and established themselves there, being afterwards annexed, first by Sweden and then by Russia. They are a strong, hardy race, who make excellent seamen, with round faces, fair hair and blue eyes. They are honest, highly moral and religious, and possess a remarkable ballad and folk-tale literature, of which the Kalevala is the chief example. The Baltic Finns of allied race include Esthonians, Karelians, Lapps, Livonians and Tavastians (_q.v._). The Volga Finns are another branch of the same people, whose chief tribe was the ancient Bulgars (_q.v._). The Mordvins and Cheremisses, still settled on the banks of the Volga in small communities, belong to the same race. =Flathead= or =Salish Indians=. A mixed race of North American Indians, in British Columbia and Montana. =Flemings=, or =Flemish=. The inhabitants of Flanders, now divided between Belgium and Holland, descended from Belgic tribes settled there in Cæsar’s time. They are a Low German branch of the Teutonic stock. They are an industrious and honest, though phlegmatic, people, who played a great part in mediæval commerce. =Formosans.= Natives of Formosa, of mixed Malayan and Negrito descent. They were divided into three classes by the Chinese invaders: the Pepohwan, civilised agriculturists, under Chinese rule; Sekhwan, settled tribes who acknowledged Chinese rule; and Chinhwan, the wild savage tribes of the mountains, who waged unceasing war against the invaders. The island has now passed under Japanese dominion. The Formosans in general approximate to the Malay type, but are more sturdily built. =Fox Indians.= See ALGONQUIAN. =Franks.= A confederation of Germanic tribes, dwelling on the Middle and Lower Rhine in the third century. They belonged to the High German branch of the Teutonic stock. In the third and fourth centuries they began to invade Gaul, where they established a Frankish kingdom under Clovis (481-511), who adopted Christianity. This later developed into the modern State of France. The Franks were a brave and stalwart race of warriors, with blue eyes and long flowing hair, well-built and large-limbed. They were a nation of democratic fighting men, who practised agriculture in the intervals of war. =French.= The inhabitants of modern France, a race of mixed origin. Among their ancestors are the Celtic Gauls, the Teutonic Belgae and Franks, the Hamitic Iberians, the Romans, and the Scandinavian Normans (_q.v._). They are probably the quickest-witted and most intelligent race of modern Europe. Extremely warlike and aggressive in earlier days, they are now displaying greater devotion to the arts of peace, especially agriculture. Paris has long been the chief centre of ideas in Europe. =Frisians.= A Teutonic race of Low German stock, living between Scheldt and Weser in Roman times, now belonging to the Netherlands. =Fuegians.= Natives of Tierra del Fuego in South America, savages of a very low physical and mental type. =Fulahs.= A warlike and predatory race of Saharan Hamites, formerly occupying small communities throughout the West and Central Sudan, who over-ran the native Hausa States about 1800-1810, and founded the empire of Sokoto. =Furs.= See NUBA GROUP. =Ga.= A Sudanese Negro group in Guinea, including Accras and Krobos. =Gaels.= See HIGHLANDERS. =Gaikas= and =Galekas=. See XOSAS. =Galchas.= Highlanders of Hindu Kush and Turkistan, of Iranian descent. =Gallegos.= Natives of Galicia, in Spain, of Gothic descent. =Gallas.= A branch of Eastern Hamites, occupying Gallaland, south of Abyssinia. The finest people in all Africa, strongly built, of a light chocolate colour. They are distinguished for their energy and honesty. They are divided into numerous tribes, and are inveterate foes of the Somalis. =Gallinas.= Sudanese Negroes of Sierra Leone. =Garamantes.= An ancient Hamitic race inhabiting the neighbourhood of Tripoli in Roman times. =Garhwalis.= Tibetan natives of Garhwal, on the border of Tibet. =Gascons.= Natives of Gascony, of Basque descent, modified by Frank and French blood. They are notorious for their lively imagination and boasting “Gasconades.” =Gauchos.= A mixed race of Spanish and Indian descent, admirable horsemen, who are the chief herdsmen of Uruguay and the Argentine Republic. See PUELCHES. =Gauls.= In Cæsar’s time the Gauls occupied the central part, and formed the chief race, of modern France, which, after them, was called Gaul. They probably belonged to the Brythonic division of the Celtic stock, being closely allied to the ancient Britons, as well as to the modern Welsh and Bretons, who respectively represent the remnants of the primitive Celtic population of England and France. It is possible that there was a still earlier Celtic element in France, corresponding to the Goidelic division of the Celtic stock. Mingled with the Celtic element in the Gauls were traces of the earlier Iberian and Ligurian aborigines (_q.v._). The Gauls were blue-eyed, fair-haired and long-headed, in distinction to the older dark-eyed, black-haired, round-headed type, which is more commonly known as Celtic, but is probably characteristic of an older race. Under Roman rule the Gauls acquired a considerable degree of civilisation. They were dispossessed in the decline of the empire by Franks, Burgundians and Visigoths (_q.v._), but became in part ancestors of the modern French. =Georgians.= The chief race of the Southern Caucasus, a fine athletic race of pure Caucasic type, noted for the personal beauty of its individuals. The Georgians were formerly fierce and warlike, but under Russian rule have become industrious in the arts of peace. They are noted for a passionate love of music. They first appear in history in the time of Alexander the Great, when they were already settled in their mountains. The Georgian kingdom had an independent existence for about seven centuries, but suffered much from Mongolian and especially Turkish invasions. Georgia and Circassia furnished the majority of white slaves for Turkish harems. In 1801 Georgia was annexed to Russia. Other important South Caucasian races are the Imerians and the Mingrelians, who closely resemble the Georgians in physical characteristics, but have displayed less aptitude for civilisation. =Gepidæ.= See GOTHS. =Getæ.= An ancient race of Thracian (_q.v._) descent, who settled in Wallachia in the fourth century B.C. They were warlike and turbulent, but were conquered by Trajan and incorporated in the Roman Empire. In later centuries they appear to have been fused with the Goths (_q.v._). =Germans.= The Germans first appear in history as a multitude of independent and warlike tribes living amongst the dense forests which stretched in Roman times from the Rhine to the Vistula. They belonged to the Teutonic stock of the Aryan family. They were a tall and vigorous race, with long, fair hair and fierce blue eyes, who delighted in war and the chase. Their democratic social organisation has greatly influenced all Teutonic history; their love of liberty was a passion. At an early period they were divided into High and Low Germans, differing in type, according as they inhabited the central and southern portions of modern Germany or the low-lying lands towards the North Sea and the Baltic. The chief races of the former were the Goths, Franks, Burgundians, Swiss, Swabians, Austrians; of the latter, Saxons, Angles, Jutes, Frisians, Flemings, Batavi--from whom the modern English and Dutch are descended, whilst the High Germans represent the modern Germans. These are a very enterprising, thorough, and industrious race, alike in war and peace, and have thus given birth to one of the greatest Powers of the modern world. =Ghilzais.= See AFGHANS. =Gilyaks.= A Siberian Mongolic race of Saghalien. =Gipsies.= A nomadic race, which was first described as appearing in Europe in the fifteenth century, and is now found in nearly all civilised countries. At first they were believed to come from Egypt, and their name is a corruption of “Egyptians.” They have a dark, tawny skin, black hair and eyes, are small-handed and often very handsome, and live by tinkering, basket-making, fortune-telling, and other arts which can be practised on the road. Their chief characteristic is independence and love of a wandering life. Their origin is still uncertain; though their language, Romany, is known to be a corrupt dialect of Hindi, which supports the older theory that they are of Indian descent. A later and well-supported theory is that they are the descendants of the prehistoric race which introduced metal-working into Europe. On this view they must have existed in Europe from time immemorial, without being noticed in literature. The gipsy problem still awaits solution. =Goajiris.= See TUPI-GUARANI. =Golden Hordes.= See KIPCHAKS. =Gonaquas.= Hottentot Negro half breeds on Kafirland frontier. =Goads.= See DRAVIDAS. =Goths.= One of the chief Teutonic races of ancient times, who played a great part in European history from the third to the eighth century, but have left no descendants as a distinct race. They first appear in history in the third century, as a confederation of German tribes who had made a settlement in the district north of the Lower Danube. They soon split up into two distinct peoples, the East Goths or Ostrogoths, and the West Goths or Visigoths. There was a third and unimportant race of Mœsogoths, settled in Mœsia, for whom Ulfilas made his famous translation of the Scriptures. The Goths were extremely warlike and aggressive, a typical race of German warriors. The Ostrogoths remained north of the Danube, where they were subjugated for a time by the Huns of Attila. Recovering their independence, they invaded Italy, destroyed the Western Empire, and established a new kingdom under Theodoric. This was conquered by the Byzantine Narses in 552, after which the Ostrogoths disappear from history. The Visigoths, unwilling to submit to the Huns, crossed the Danube and settled in the Roman Empire, where they furnished many recruits for the army. In 395 they rebelled, and under Alaric invaded Italy and besieged Rome. Afterwards they founded kingdoms in the south of Gaul and in Spain, where the Visigoths ruled till the invasion of the Saracens, and where their blood is still found incorporated with that of the older races. A branch of the Ostrogoths which settled in the Crimea preserved its nationality and language down to the sixteenth century, or even later. The Bastarnæ, Gepidæ, and perhaps the Vandals (_q.v._), were branches of the Gothic race. =Greeks.= (1) For ancient Greeks, see HELLENES. (2) The modern Greeks are partly descendants of ancient Greeks, with a large admixture of Albanian, Wallachian and Slavonic elements. They are great in commerce, but not warlike. =Griquas.= A race of Hottentot-Dutch half-breeds, also known as Bastaards, in Griqualand. =Guaicuris.= Central American Indians of Lower California. =Guanches.= Aborigines of Canary Islands: so-called “White Africans,” probably of Berber Hamitic stock. =Guatemalans.= White natives of Guatemala, in Central America, of Spanish descent. =Guatusas.= Central American Indians of Costa Rica. =Guebres.= See PARSEES. =Gujeratis.= Natives of Gujerat in Western India, Aryans of Hindu stock. =Gurkas.= The dominant race of Nepal, who claim a Hindu (Aryan) origin, but have probably acquired a Mongoloid tinge from inter-marriages. They are of small stature, yet eminently warlike, and supply some of the best troops to our Indian Army. =Gypsies.= See GIPSIES. =Hadendowas.= See BEJAS. =Haidas.= North American Indians in British Columbia. =Hamites.= A family of Caucasic Man, belonging to the Melanochroid or dark type, ranging in colour from white to brown, and even black; hair soft, straight or wavy; skull, medium (mesocephalic); square-jawed (orthognathous); generally of fine physical development. Divided into Eastern Hamites--_e.g._, Somali, and Western Hamites--_e.g._, Berbers and Basques. Closely related to Semites. =Hau-Khoin.= See HEREROS. =Hausas.= The most important Sudanese Negro race of Northern Nigeria. Keen traders, physically well developed, they make excellent soldiers, and are largely utilised for this purpose by their British rulers. The Hausa States were over-run by the Hamitic Fulahs (_q.v._) about 1800-1810, and now form part of the Empire of Sokoto. The Hausa language is the common medium of commerce in the Central Sudan. =Hawaiians.= Natives of Hawaii, of brown Polynesian stock, akin to Maoris. A remarkably fine and handsome race, steadily decreasing since contact with European civilisation and diseases. Peculiarly subject to leprosy. =Haytians.= Natives of the negro republic of Hayti, descended from negro slaves imported by the earlier Spanish and French owners, who freed themselves at the time of the French Revolution. The Spanish portion afterwards formed the Dominican Republic in the eastern part of the island. Of mixed Bantu and Sudanese Negro descent, with a cross of white blood. =Hazaras.= Mountaineers of N.W. Afghanistan, a vigorous and turbulent race of Mongolo-Persian descent, often troublesome to British India. =Hebrews.= See JEWS. =Hellenes.= Inhabitants of ancient Greece, which they called Hellas. The Proto-Hellenes, or aborigines, were probably of Pelasgian origin, belonging to the Western Hamitic family, of whom the ancient Cretans and Mycenæans (_q.v._) may represent the ancestral type. These were followed by the true Hellenes--Achæans or Argives--divided into three main branches--Dorians, Ionians, and Æolians. Later they were divided into many local states, such as Athens and Sparta. The modern Greeks are in part descended from the Hellenes, crossed with Albanian, Wallachian, and Turkish blood. It is to the Hellenes that we owe the first important developments of civilisation in Europe. =Helveti.= Ancient inhabitants of Switzerland in Cæsar’s time, probably a German tribe, from whom the modern Swiss are in part descended. =Hereros=, or =Ovaherero=. Bantu Negroes inhabiting the plains of Damaraland, or German South-West Africa. The Damaras or Hau-Khoin are a cross between Hereros and the Hottentot aborigines. A pastoral nation who migrated thither about two centuries ago from the inland districts, and dispossessed the aboriginal Hottentots, now represented by the Namas of Namaqualand, with whom they are perennially at war. Recently they rose against the German authorities, and have given them much trouble. A fine, warlike race. =Highlanders.= The Gaelic-speaking inhabitants of Northern Scotland, a branch of the Goidelic or Q Kelts, also known as Gaels. They are descended from the ancient Scots (_q.v._), who originally migrated from Ireland in the fifth century. One of the finest races of the British Islands, who give them their finest soldiers. =Himyarites.= A branch of the Semitic family (“Red Men,” whence the Red Sea), formerly occupying Arabia Felix and Abyssinia; they form the main stock of the Abyssinian race. They included the kingdoms of the Minæans and Sabæans, the latter being identified by some with the Biblical Sheba. =Hindus.= A stock of the Aryan family, comprising a large proportion of the natives of India, described under the headings of Kashmiris, Punjabis, Rajputs, Marathas, Bengalis, Sindis, Gujeratis, Assamis, etc. The original Hindus entered India--hence called Hindustan--from the north-west at some prehistoric time, and soon became the predominant race in the peninsula. =Hittites.= A forgotten but once mighty people of Semitic race, who contested the entry of the Israelites into Canaan, and waged war with Egypt and Assyria for many centuries. Little is known about them, but they seem to have reared a mighty empire between Lebanon and the Euphrates, which endured for more than a thousand years, and was destroyed by the Assyrian Sargon II. in 717 B.C. =Hondurans.= White natives of Honduras, of Spanish descent; few in numbers, the population being mostly of mixed blood. =Hor-Soks.= A primitive Mongol-Turki race of the Tibetan plateau. =Hottentots=, or =Khoi-Khoin=. The aboriginal Negro inhabitants of South Africa, which they shared with the Bushmen (_q.v._). Possibly the Bushmen are degraded Hottentots, or the Hottentots are a cross between the Bantus from the north and the Bushmen, who would on this view be the true aborigines. The only surviving race of pure Hottentots are the Namas of Namaqualand: the Damaras, Griquas, Gonaquas, and Koranas, are other races in which Hottentot blood is mixed with that of Bantu Negroes or of Europeans (mostly Boers). The Hottentots are a distinct branch of the Negro family, marked by extremely long heads and high cheek-bones, a brownish-yellow complexion, with other physical peculiarities exemplified in the so-called “Hottentot Venus,” and also found in the Bushmen. Their language is peculiar for its unique “clicks,” which no European can pronounce, and which seem to stand between articulate and inarticulate speech. =Hovas.= The dominant Malagasy race of Madagascar, of Malay descent, mixed with Bantu Negro blood from Africa. They stand nearest to pure Malays of all Malagasy peoples. The existing French Protectorate was only established after much fighting with the warlike Hovas, who had conquered all the other native tribes. =Huastec.= See MAYA-QUICHÉ. =Hungarians.= See MAGYARS. =Huns.= A nomad race of the Northern Mongolic family, probably of Turki stock, who settled in the neighbourhood of the Volga and the Urals about the dawn of the Christian era. In the fourth century they conquered and dispossessed the Ostrogoths and Visigoths on the Danube. Under Attila, in the fifth century, they invaded Greece and Gaul, and pushed their arms as far as Rome, which was only saved by the diplomacy of the Pope. Their cruel fierceness in war caused their great leader to be known as the Scourge of God. Like the Mongols, they were essentially a race of horsemen, and their “deformed figures and hideous Mongolic faces” added to the terror which they inspired. After Attila’s death in 453 the Huns fell to pieces, and soon were absorbed into other nations--especially, perhaps, the Bulgars. =Hunzas.= See DARDS. =Hupas.= See ATHABASCAN. =Hurons=, or =Wyandots=. A North American Indian race of Iroquoian stock, formerly inhabiting the shores of Lake Huron. =Hyksos.= A Northern Mongolic race who invaded Egypt and established the dynasty of the Shepherd kings about 2000 B.C. =Ibeas.= A Negro race which recently invaded the Cameroons from the East: they bring down ivory from the unexplored interior. Either Bantu, or Sudanese--perhaps connected with the Azandeh (_q.v._). =Iberi=, or =Iberians=. An ancient race of Western Hamites, related to the fair Berbers of Mauritania. The Basques are probably descended from them, and there is good reason for identifying them with the Picts of Scotland and the Irish aborigines. =Ibo.= See ABO. =Icelanders.= Inhabitants of Iceland, originally Norwegians, who settled there about the end of the ninth century. A typical tall, fair-haired, blue-eyed Scandinavian race. The Icelandic Sagas form the chief part of ancient Scandinavian literature. =Idumæans= or =Edomites=. A warlike Semitic race of Canaanite stock, thought to be descended from Esau, who were conquered by the Israelites under Saul and David, and again by Judas Maccabæus in 165 B.C., after which they disappear from history. =Ife.= See YORUBAS. =Igorrotes.= An industrious agricultural race of the Philippine Islands. Indonesians of Malay descent, with a possible Chinese or Japanese element. =Illinois Indians.= See ALGONQUIAN. =Illyrians.= A savage piratical race of the eastern Adriatic sea-board, who were conquered by the Romans, and were the last of the Balkan peoples to be civilised. Probably the modern Albanians are descended from them, and they were among the first Aryan immigrants to Europe. =Ilocanos.= A Malay race of the Philippine Islands. =Imerians.= See GEORGIANS. =Incas.= The chief of the six Indian races, including the Quichuas and the warlike Chancas, which formerly occupied the central mountain-region of Peru. The Incas became the dominant race about 1000 A.D., and built up a vast and peaceful civilisation, in which a purely socialistic government was successfully administered. This Inca Empire was destroyed by the Spanish under Pizarro in 1533, but the Inca Indians still survive as a race in Central Peru, where they are known as industrious and honest agriculturists. =Indians.= Native races (1) of India; (2) of North, Central, and South America. =Indo-Chinese.= A section of the Southern Mongolic family, inhabiting the countries between India and China. =Indo-European, Indo-German.= See ARYAN. =Indonesians.= The light-coloured, non-Malay inhabitants of the Eastern Archipelago and South Sea Islands, who are of Caucasic type, and are mostly brown-skinned Polynesians (_q.v._). They also include the Batjans of Batjan I., the Burus, Korongui, and Suvu of the Malay Archipelago, and the Mentawey Islanders (_q.v._). =Ingushis.= See CHECHENZES. =Innuits.= See ESKIMOS. =Ionians.= (1) One of the three main Hellenic races of ancient Greece. (2) Greek inhabitants of the coast districts and islands of Western Asia Minor, forming the Ionian League, who passed in the sixth century B.C. under the Persian sway. =Iowa Indians.= See SIOUAN. =Iranians.= Ancient inhabitants of the Asian plateau bounded by the Indus, the Tigris, and the Hindu Kush. A stock of the Aryan family, now including Persians, Afghans, Baluchis, Kurds, and Armenians (_q.v._). =Irish.= (1) The aborigines of Ireland, probably Iberians (_q.v._). (2) The later Erse-speaking inhabitants of Ireland, a branch of the Goidelic or Q Celts. (3) Modern inhabitants of Ireland, mostly Celtic, but largely mixed with Teutonic elements in the north. =Iroquoian.= One of the families of North American Indians, including the Iroquois, or “Six Nations,” who comprised the Mohawks, Oneidas, Onondagas, Senecas, Tuscaroras and Cayugas; the Hurons, or Wyandots, including the Eries, and the Cherokees. Their territory was Upper Canada, round the great lakes, New York, and the Virginian Highlands, and they played a large part in the Franco-British warfare of the eighteenth century. They are now few in numbers and confined to Indian Reservations in the U.S. and Canada. =Israelites.= See JEWS. =Italians.= (1) Ancient inhabitants of Italy, of Ligurian stock, probably Eastern Hamites, related to the Pelasgians [see LATINS and ROMANS]. (2) Modern Italians, mostly of Latin stock, crossed with Teutonic (Gothic and Lombard) blood. =Italic.= A stock of the Aryan family, including ancient and modern Italians (with ancient Romans), modern French, Spanish, Portuguese, and Roumanian, with Latin (Spanish and Portuguese) Americans. =Jallonké.= See MANDINGAN. =Jangalis.= An aboriginal Indian tribe, inhabiting the forest district north of Cuttack--the most primitive race in all India. Perhaps an early Dravidian (_q.v._) stock. =Japanese.= A race of the Northern Mongolian family, probably originating in Korea, whence they spread to Japan and dispossessed the Ainu aborigines, about the dawn of the Christian era. The most enterprising and civilised people in Asia, often called “the English of the Far East.” They possess a singularly high standard of honour and patriotism, which was the main factor in their recent victory over Russia, and they are eminently warlike, besides producing industrious agriculturists and enterprising traders. Of short but sturdy stature, white skin and yellow or sallowish complexion, oblique eyes, black hair. =Jats.= A numerous agricultural race of the Punjab in North-west India. They are probably of an Aryan stock, but ethnologists disagree as to their history, assigning them ancient Scythian invaders, the Rajputs, or the Gipsies, for ancestors. =Javanese.= A Malay race inhabiting Java, where they dispossessed the Negrito aborigines [see KALANGS] in prehistoric times. The Sundanese and Madurese are allied tribes, possessing parts of the island of Java, now under Dutch rule. =Jebus.= See YORUBAS. =Jews=, =Hebrews=, or =Israelites=. The most important of Semitic races, of the ancient Canaanite stock. The Israelites descended from Abraham, who came from Mesopotamia to Canaan about 2000 B.C.; thence they migrated to Egypt, and returned to take possession of Palestine. Their history is familiar to all from the Bible. After the Roman capture of Jerusalem under Titus, 70 A.D., the Jews--as they were now called--were dispersed through the world, but they have retained their racial characteristics in remarkable purity through long persecutions, and now play a great part in the commerce and finance of nearly all civilised countries, though they have no national unity or racial home. =Jivaros.= South American Indians, in Peru, on the head-waters of the Amazon. =Jolofs.= See WOLOFS. =Jutes.= Early inhabitants of Jutland, a Low German branch of Teutonic stock, who invaded England in the fifth century and made the first Teutonic settlement in that country, in Kent. =Kabards.= A Western Caucasian race, allied to the Circassians (_q.v._) and presenting a high standard of physical beauty. =Kabyles.= See BERBERS. =Kacharis.= Natives of the Terai at the foot of the Himalayas, belonging to the Tibetan stock of the Southern Mongolic family. =Kafirs=, or =Kaffirs=. Generic name of the fierce and warlike Bantu Negro races which occupied the south-eastern seaboard of South Africa when Europeans first colonised that country. They then held all the coast lands from the Gamboos to the Limpopo. The southern part (Kaffraria) belonged to the Kafirs proper, and the northern (Zululand) to the Zulus, an allied race, but usually distinguished from the Kafirs, or Ama-Xosa, whose chief tribes are Galekas, Gaikas and Tembus (_q.v._). Throughout the greater part of the nineteenth century the English settlers were engaged in constant Kafir wars, which resulted in the gradual subjugation of both Kafirs and Zulus. =Kafirs.= Fair-skinned mountaineers of Kafiristan, between the Kabul River and Hindu Kush. An offshoot of the Aryan family, thought by some to be descendants in part of the Greek troops with which Alexander the Great invaded India. =Kakhyens.= A race of freebooters, inhabiting the northern frontiers of Burma, whence they raid the more civilised agriculturists of the plains and levy blackmail. A Southern Mongolic race of Indo-Chinese stock. =Kalangs.= A recently extinct Negrito race of Java, remnants of the aborigines of that island; small, black and woolly-haired, with very retreating forehead and projecting jaws. The most ape-like of human beings, and the nearest approach yet found to the “missing link” between man and ape. They belonged to the Oceanic Negro family. =Kalmuks.= The Western Mongol stock of the Northern Mongolic family, scattered through Central Asia, and extending into Southern Russia. Nomadic pastors, owning large flocks and herds, and living in tents on the great steppes, they include the tribes of the Chorasses, Turguts, Khoshots, and Durbats. A large horde of Kalmuks invaded Russia in 1650, and settled there for a century, but in 1771 most of them were expelled, and endured great sufferings on the march to China, so brilliantly described by De Quincy. These were mainly Khoshots and Durbats. =Kamchadales.= A Siberian branch of the Northern Mongolic family, inhabiting Kamchatka; a hardy race of hunters and fishers. =Kanakas.= A name given to South Sea Islanders, generally by sailors and traders, and especially to Polynesian labourers imported to Queensland. =Kanakas=, or =Bakanaka=. Negro aborigines of Angola, probably akin to the Bushmen. Other similar tribes are the Korokas, Kulabes, Kwandes and Kwisses. =Kanarese.= Mongoloid aborigines of Mysore in India. See DRAVIDIANS. =Kanembu, Kanuris.= See LAKE CHAD GROUP. =Kara-Kalpaks=, or =Black Bonnets=. A branch of the Turki stock of the Northern Mongolic family, dwelling on the south-east of the Aral Sea and in the Oxus basin. A pacific pastoral race, dominated by their warlike relatives, the nomadic Kirghiz, and now subject to Russia. =Kara-Kirghiz.= See KIRGHIZ. =Karelians.= An Eastern branch of Baltic Finns dwelling in the eastern parts of Finland and adjoining provinces of Russia. Probably a Slavo-Mongolic mixture in which the original Mongolic element has been largely eliminated. =Karens.= Inhabitants of Burma, of the Indo-Chinese branch of the Southern Mongolic family. Largely Christianised. Formerly oppressed by the Burmans, than whom they are less clever, but more industrious. Agriculturists. =Karons.= A Negrito race of New Guinea, of very degraded type, and addicted to cannibalism. =Kargos.= See NUBA GROUP. =Kashmiris.= Natives of Kashmir, belonging to the Hindu branch of the Aryan family. Of fine physique, but corrupt and untrustworthy. =Kassonké.= See MANDINGAN. =Kazaks.= See KIRGHIZ. A RED INDIAN CHIEF AND HIS FAMILY Underwood & Underwood ] =Kelts=, or =Celts=. A stock of the Aryan family which settled in France and the British Islands in prehistoric times. The Gauls and Belgæ of Cæsar’s time and the early Britons represent them. They are divided into two branches, Goidelic and Brythonic Celts, respectively known also as Q and P Celts, from a linguistic peculiarity. The former are represented in modern times by Irish, Manx, and Scottish Highlanders; the latter by Welsh, Cornish, and Bretons. The typical Celt was probably a tall, broad-headed individual, with prominent nose, high cheek-bones, light hair and eyes. The small, round-headed, dark race which is also classed as Celtic, is more probably an earlier Hamitic type, allied to the Basques (_q.v._). =Khulkas.= A nomadic race of Eastern Mongols, occupying the Gobi desert. =Khamtis.= An Assamese race--Indo-Chinese stock of Southern Mongolic family--in the Brahmaputra Valley. =Khasis.= An Indo-Chinese hill tribe of Southern Mongolic family, in Khasi Hills of Assam. =Khoi-Khoin.= The name given to themselves by the Hottentots (_q.v._). =Khoshots.= See KALMUKS. =Kickapoos.= See ALGONQUIAN. =Kiowas.= A North American Indian race in Oklahoma. =Kipchaks.= A Turki race of Northern Mongolic family, settled in eleventh century between Urals and Don. In the middle of the thirteenth century, Batu Khan, a son of Genghiz Khan, led them to conquer all Central and South Russia, where they founded the Empire of the Golden Horde. It was broken up by Tamerlane about 1390, and from its fragments arose the Khanates of Astrakhan, the Crimea, etc., now absorbed by Russia. From the Eastern Kipchaks are descended the Kirghiz (_q.v._), one of whose hordes is still known as Kipchak. The modern Kipchaks are nomadic, and live by stock-feeding in the steppes of western Turkestan. =Kirantis.= A Tibetan race of East Nepal, of Southern Mongolic family. =Kirghiz.= A nomadic people of Central Asia, where they occupy the vast steppes which lie to the north of Turkestan. They are descended from the Kipchaks (_q.v._) of the Golden Horde. They form a group of the Turki stock of the Northern Mongolic family. The Kara-Kirghiz, who inhabit the uplands between the Issik-Kul and the Kuen-Lun, are the oldest Turki nomads of whom there is any historical record, and are divided into On and Sol--right and left wings. The Kirghiz proper, who call themselves Kazaks, or “riders,” roam from Lake Balkash to the Volga, over the vast level steppes, where they dwell in skin tents and support themselves by breeding camels, horses, oxen, sheep and goats. They live in the saddle, and were formerly a warlike people, who once could put 400,000 fighting men in the field. They are divided into four hordes--Great, Middle or Kipchak, Little, and Inner. They are all now under Russian dominion. =Kishis.= See CHECHENZES. =Kissis.= See TEMNÉ GROUP. =Kizil-Bashis.= Persianised Turkis of Afghanistan, belonging to Turki branch of Northern Mongolic family, who supply the chief commercial classes of Afghanistan. =Kolajis.= See NUBA GROUP. =Kolarians.= One of the three non-Aryan races to which the primitive inhabitants of India belonged, of the Indo-Chinese stock of the Southern Mongolic family. They entered Bengal from the north-east, and are now represented by a few scattered tribes, like the Santals, Mundas, Kurkus, and Bhils. =Koranas.= See HOTTENTOTS. =Koreans.= Natives of Korea, belonging to the Koreo-Japanese stock of the Northern Mongol family. They stand midway between Chinese and Japanese, the latter being probably their descendants, and are taller, with lighter complexion and more regular features, than the typical Mongol. Their civilisation is of Chinese origin. They are not warlike, but are prosperous agriculturists. =Korokas.= See KANAKAS. =Korungas.= See WADAI GROUP. =Koryaks.= An Arctic race of North-east Siberia, allied to the Chukchis (_q.v._). =Krej.= See NILITIC GROUP. =Krim-Tartars.= See TARTARS. =Krus=, or =Krooboys=. Sudanese Negroes of Liberian Group. Bold and skilful boatmen, employed for that purpose all along the West African Coast. =Kulabes.= See KANAKAS. =Kulfans, Kunjaras.= See NUBA GROUP. =Kurds.= Native of Kurdistan, partly nomad and pastoral, partly settled and agricultural. A fierce and warlike people, they are much given to raiding, and were utilised by the Sultan to oppress the Armenians. They have settled in Kurdistan from time immemorial, and belong to the Iranian stock of the Aryan family. =Kurile Islanders.= See AINUS. =Kurinis.= See LESGHIANS. =Kurkus.= A broken Kolarian tribe, allied to the Santals of Central India, belonging to the Indo-Chinese branch of Southern Mongolic family. =Kutchins.= See ATHABASCAN. =Kwandes, Kwisses.= See KANAKAS. =Ladakhis.= Natives of Ladakh in the Upper Indus Valley, belonging to the Tibetan stock of the Southern Mongolic family, conquered by Kashmir in seventeenth century. =Lake Chad Group.= A group of Sudanese Negro tribes, inhabiting the districts round Lake Chad, including Kanembus, Kanuris, Baghirmis (warlike slave-raiders), Mandaras, Yedinas, Logons, Mosgus, Bulalas, Saras, etc. =Lampongs.= Malay inhabitants of Southern Sumatra. =Lamuts.= See TUNGUSES. =Landumans.= Sudanese Negroes of Senegambia. =Laos.= See SHANS. =Lapps.= A branch of the Finno-Ugrian stock of the Northern Mongolic family, inhabiting the parts of Norway, Sweden, Finland, and Russia collectively known as Lapland. They are the shortest and broadest-skulled people in Europe. Most of them are nomads, who live by their vast reindeer herds, though some have become settled and live by fishing and hunting. They are closely allied to the Baltic Finns, and like them show traces of a mixture of Caucasic blood. =Lascars.= A term applied to sailors of Indian and Malay seafaring races, employed on British vessels. =Latins.= The ancient inhabitants of Latium, the district of Central Italy which lay between the Tiber and the Liris, and included the Roman Campagna. They absorbed the earlier allied races of Oscans, Sabines, Samnites and Umbrians, and formed a league of thirty cities, which warred for some generations with Rome and then fell under the Roman dominion. Rome itself was originally a Latin city. The ancient population of Italy was divided into three grades: Roman citizens--not necessarily residents in Rome--Latins, and Italians. The Latins are a branch of the Italic stock of the Aryan family. =Latin= or =Romance Races=. A name often given to the modern races which speak a Romance language derived from Latin, and belong in whole or part to the Italic stock of the Aryan family. They include Italians, French (including Provençals), Spaniards, Portuguese, and Roumanians. =Latin Americans.= The white inhabitants of South America, of Spanish or Portuguese descent, and speaking these languages. =Lazes.= See GEORGIANS. =Lencan.= A group of semi-civilised Central American Indian tribes, including Chontals, Ramas, Payas, Wulwas, and Guatusas. =Lepchas.= Natives of Sikkim and Bhutan, belonging to the Tibetan stock of the Southern Mongolic family. =Lesghians.= A branch of the Eastern stock of the Caucasian family, inhabiting the Eastern Caucasus. Wild mountain tribes, who long offered an unavailing resistance to the Russian arms under Shamyl (1859). Their chief tribes are the Avars (the most cultivated and powerful), Andis, Dargos, Didis and Kurinis. =Lettic.= A stock of the Aryan family, including Letts, Lithuanians and the extinct Pruczi, Borussians, or Old Prussians, from whom modern Prussia takes its name. The Letts and Lithuanians in the fifteenth century formed a united people, inhabiting the south-west of Russia, from Courland to Odessa. Afterwards they passed under Polish and then Russian dominion. They are now mostly peasant agriculturists. They are fair and well-built, with fine features and blue eyes. =Letts.= See LETTIC. =Liberian Group.= Sudanese Negro tribes, inhabiting the Grain Coast of West Africa. The Krus or Krooboys (_q.v._), Queahs and Bassas are their chief tribes. =Liberians.= Natives of the negro republic of Liberia on the Guinea Coast, partly descended from freed slaves of all races, but mainly belonging to the Liberian group. =Libyans.= An ancient fair-haired and light-skinned race of Northern Africa, akin to the modern Berbers, belonging to the western stock of the Hamitic family. They are depicted on Egyptian monuments of fifteenth century B.C. =Ligures=, or =Ligurians=. An ancient race of the western stock of the Hamitic family, probably the aborigines of North-West Italy round Genoa, to whom the Siculi, Sards and Corsicans were apparently akin. =Limbas.= See TEMNÉ GROUP. =Lithuanians.= See LETTIC. =Livonians.= A branch of Baltic Finns, belonging to the Finno-Ugrian stock of the Northern Mongolic family; a dwindled remnant now inhabits the Baltic provinces of Russia. =Logons.= See LAKE CHAD GROUP. =Lolos.= A fair-complexioned aboriginal race on the frontiers of China and Tibet, belonging to the Chinese stock of the Southern Mongolic family. =Lombards.= A race of Teutonic stock, formerly settled in the district of the Lower Elbe, who invaded Italy in 568, and there founded a powerful Lombard kingdom under Alboin and his successors. The Lombards were at first fierce warriors and little more; but they soon fell under the influence of Italian civilisation, and were merged into the Italian race when Charlemagne destroyed their independence in 774. Their name and some traces of their racial character still remain in Lombardy, between the Alps and the Po. =Luchuans.= Natives of the Luchu or Liu-Kin Archipelago, between Japan and Formosa, resembling the Japanese, but with differences which are attributed to a cross of the aboriginal Ainu blood. They belong to the Koreo-Japanese stock of the Northern Mongolic family. =Lushais.= A warlike race of Tibetan stock inhabiting the Lushai Hills on the confines of Assam, Bengal and Burma. =Mabas.= See WADAI GROUP. =Macedonians.= A warlike people of ancient Greece, who attained their greatest power under Alexander the Great. They were not true Hellenes, but a race of wild mountain tribes probably of Hamitic origin. Modern Macedonia is peopled by an extremely mixed race of Greeks, Bulgarians, Turks, etc., among whom some descendants of the ancient Macedonians may no doubt be found. =Macusis.= See CARIBS. =Madis.= See NILITIC GROUP. =Madurese.= A Malay race inhabiting Java, and allied to the Javanese (_q.v._). =Magars.= A Tibetan tribe of Western Nepal. =Magwangwaras.= A fierce predatory race of Bantu Negroes, occupying the head-waters of the Rovuma River in East Central Africa. =Magyars.= A warlike and now highly civilised race belonging to the Finno-Ugrian stock of the Northern Mongolic family. They first appeared in Europe about a thousand years ago, being probably Scythian (_q.v._) immigrants from the Caspian district. They conquered the Roman provinces of Pannonia and Dacia, and there founded the Kingdom of Hungary in the year 1000. They are still the dominant race in Hungary, which now forms part of the Austro-Hungarian Empire, and preserve their Finno-Ugrian speech. They are a chivalrous and highly intelligent race, whose Mongolic descent is no longer perceptible in their white skins and regular, often handsome features. Probably this is due to frequent crossing of blood with German, Slav and Roumanian neighbours. =Mahrattas.= See MARATHIS. =Makololos.= A warlike branch of the Basuto race of Bantu Negroes who, in 1835, moved north and conquered the Barotses, only to be reduced by them to vassalage about 1864. =Makuas.= A savage cannibal race of Bantu Negroes, living north of the Zambesi in Portuguese East Africa. =Malagasy.= A Malayo-African people of mixed blood, inhabiting Madagascar. The Hovas (_q.v._) are the dominant tribe. =Malays.= The dominant native race of Malaysia, the chief stock of the Oceanic Mongolic family. They are of a distinctly Mongolic physical type, of low stature and yellowish colour, with high cheek-bones, black lank hair and broad skulls. They may be divided into three races: the Orang-Benua, or men of the soil, the indigenous Malay tribes at a low stage of culture; the Orang-Laut, or men of the sea, who live by fishing and piracy; and the Orang-Malayu, or civilised Malays proper. They inhabit the southern provinces of Sumatra, the native states of the Malay Peninsula (Kelantan, etc.), the British Straits Settlements (Johor, Perak, Selangor, etc.), parts of Borneo, Ternate, Tidor and the Banda Islands, and many islands of the Malay Archipelago. They have wandered as far as Madagascar, where the Malagasy (_q.v._) are Malays crossed with Negro blood. They were formerly warlike and much given to piracy, but are now the chief trading race of South-eastern Asia. Their origin is dubious, but Sumatra is generally regarded as their original home. Of kindred blood are many so-called Proto-Malay races, such as the Achinese, Javanese, Sundanese, Dyaks, etc. (_q.v._). =Malayalim.= See DRAVIDIANS. =Manchus.= The dominant native race of Manchuria, who conquered China in the seventeenth century and founded the existing Chinese dynasty. They are of the Mongol stock of the Northern Mongolic family. They first appear in history in the thirteenth century, when a number of nomad Manchu tribes were formed into a single people. They probably originated in Siberia, where the Tunguses (_q.v._) represent their primitive stock. =Mandans.= See SIOUAN. =Mandaras.= See LAKE CHAD GROUP. =Mandingans.= The chief race of Sudanese Negroes in the Western Sudan, with numerous branches between the Upper Niger and the coast, including Mandé or Mandingoes, Bambaras, Jallonkés, Kassonkés, Masinas, Sarakolés, Solimas, Susus, etc. Timbuctoo was formerly the capital of the Mandingan empire, before it fell under Berber domination. A large proportion of American Negroes are descended from slaves of Mandingan origin. =Mangbattu.= Sudanese negroes of Welle group, noted for their pronounced cannibalism. =Mangkassara.= Malay natives of Macassar, in Celebes, under Dutch rule. =Manipuris.= Natives of Manipur, between Burma and Assam, mostly wild hillmen of mixed Burmese and Hindu blood, but classed with the Indo-Chinese stock of the Southern Mongolic family. =Man-Tses.= Inhabitants of the mountain districts of Sze-chuen in China, akin to Lolos (_q.v._). _m_ =Manx= or =Manxmen=. Inhabitants of the Isle of Man, belonging to the Celtic stock of the Aryan family, and the Goidelic or Q Celt branch of it. There is a strong Scandinavian element in their blood, from the numerous invasions of the old Norse pirates. Their customs are also strongly marked by the Scandinavian element. =Manyuemas.= Warlike Bantu Negroes of the Upper Congo, long allied with the Arab slave-traders. =Maoris.= The aborigines of New Zealand, belonging to the tall brown race of Polynesians (_q.v._), a branch of the Indonesian family. A brave, generous and warlike people, who are said to have reached New Zealand from the Pacific islands about a thousand years ago, they are one of the few native races which promise to assimilate western civilisation with success. =Marathis=, or =Mahrattas=. A numerous Indian race of mixed origin, probably of aboriginal (Dravidian) blood in the main, with a Hindu element. They inhabit West and Central India, where they became the dominant power under Sivaji in the seventeenth century. The English had long and bloody contests with these wild and warlike mountaineers, who founded several great native states, some of which (Gwalior and Indore) survive to this day. =Maronites.= A sturdy, warlike Christian race of mountaineers in the Lebanon, belonging to the Syrian branch of the Aramæan stock of the Semitic family. Implacable foes of the Druses, with whom they are constantly at war. =Marquesans.= See POLYNESIANS. =Masais.= A branch of the Eastern Hamites, settled in British East Africa on the Tana River. A finely-built race, whom only their chocolate colour and frizzy hair prevent from passing for Europeans. Extremely warlike and intelligent, they are confirmed raiders and cattle lifters. =Mashonas.= Natives of Mashonaland, in South-eastern Rhodesia, formerly the half-fabulous empire of the Monomotapa, and the home of a forgotten civilisation, to which the ruins of Zimbabye and other similar relics bear witness. The Mashonas are Bantu Negroes, a peaceful, industrious people, who were subjugated about 1838 by the Matabeles under Umsilikatzi, and are now under British rule. =Massachusett Indians.= See ALGONQUIAN. =Massalits.= See WADAI GROUP. =Matabeles.= A branch of the Zulu race of Bantu Negroes, which was expelled from Zululand in 1838, and conquered the Mashonas, in modern Rhodesia, under Umsilikatzi. Like the Zulus, they were proud and fearless warriors, who were only subjugated with difficulty by the English in 1893, and revolted unsuccessfully in 1896. =Matacoans.= A South American Indian race on the Vermejo River in Argentine. =Mauri.= See MOORS. =Maviti.= Bantu Negroes of the Upper Shiré in British South Central Africa, of Zulu stock, who came as conquerors from the south. =Maya-Quiché.= A group of Central American Indian races, mostly in Yucatan and Guatemala. It includes the Mayas of Yucatan, Zendals and Zotzils of Chiapas, Quichés, Chols, Pokomans, and Zutugils of Guatemala, Huastecs and Totonacs of Vera Cruz. Like the Aztecs, the Mayas possessed an ancient civilisation and system of picture writing. =Maypuris.= See ARAWAKS. =Mbengas.= Indigenous Bantu Negroes of French Equatorial Africa, about Corisco Bay. =Melanesians.= The indigenous natives of the Western Pacific Islands, forming a distinct stock of the Oceanic Negro family of Ethiopic Man. They are long-skulled, or dolichocephalic, with the lowest cephalic index of all known races, prognathous, broad-nosed, of a sooty-black colour, with black frizzy hair, and of low stature. They are at a low stage of culture, being very savage, bloodthirsty, and treacherous, mostly cannibals and head-hunters, with little social organisation. They include the Fijians and the natives of the New Hebrides, the Solomon, Admiralty, Bismarck, and Loyalty Islands, New Britain, New Ireland, New Caledonia, and other islands of the Eastern Pacific. They are closely allied to the Papuans (_q.v._), under which name some ethnologists prefer to class the whole body of Melanesians. =Melanochroi.= A suggested division of Caucasic Man, in which a pale skin is typically accompanied by dark hair and eyes; it would thus include the Hamitic and Semitic families, with the Hellenic, Italic, and Celtic stocks of the Aryan family. =Mendis.= See TEMNÉ GROUP. =Mentawey Islanders.= A remnant of the aboriginal Polynesian race dispossessed by the Malays, off the coast of Sumatra. =Mestizos.= Cross-breeds between Europeans and Indians, in Spanish and Portuguese America. =Mexicans.= See AZTECS and NAHUANS. Also the modern inhabitants of Mexico, who are of Spanish descent, with a strong infusion of Indian blood. =Micmacs.= An Indian race of Nova Scotia, in whom some ethnologists think that a trace of Norse blood, dating from the pre-Columbian discovery of America, is perceptible. =Minæans.= See HIMYARITES. =Mingrelians.= See GEORGIANS. =Minh-huongs.= Franco-Annamese half-breeds in Cochin China, an increasing race who make very valuable colonists. =Minnetarees.= See SIOUAN. =Mishmis.= A wild Tibetan hill tribe occupying the jungle-covered hills through which the Brahmaputra flows, on the northern border of Assam. Warlike and turbulent. =Missouri Indians.= See SIOUAN. =Mixtecs.= An ancient Mexican race, contemporary with the Toltecs (_q.v._), probably represented by the modern Miztecs of Oajaca. =Moabites.= An ancient pastoral race of Semitic origin, ethnologically cognate with the Israelites, who dwelt on the east of the Dead Sea, and are now extinct. =Mœsogoths.= See GOTHS. =Mohawks.= See IROQUOIAN. =Mohicans.= One of the most famous and warlike of redskin races, immortalised by Fenimore Cooper. See ALGONQUIAN. =Mojos=, or =Moxos=. A yellowish Indian race of Bolivia, akin to the Chiquitos. =Mokis.= See SHOSHONEAN. =Mongolic.= One of the four great divisions of mankind. Typically characterised by yellowish skin, broad, flat features with prominent cheek-bones, broad skulls, mesognathous jaws, and oblique, almond-shaped eyes, with black, lank and coarse hair. The Manchus are a typical Mongolic race. The Mongolic races are mostly found in Asia, which is chiefly peopled by their stocks. The name “Mongolic” has replaced the older “Turanian.” =Mongols.= A stock of the Northern Mongolic, otherwise known as Mongolo-Tartar or Ural-Altaic, family, from whom the general term of Mongolic is derived. The name seems originally to have meant “brave,” and the Mongols have provided some of the most fierce and warlike races of history. They originated as scattered tribes in modern Mongolia. Under Genghiz Khan they were formed into a confederacy which conquered the whole of Central Asia in the thirteenth century, thanks to an unlimited supply of hardy and very mobile horsemen. The existing Mongol tribes, nomad pastors of Mongolia in Central Asia, are divided into Sharras or Eastern Kalmuks, or Western Buriats, or Siberian Mongols, and Tunguses, including Manchus (_q.v._). =Montenegrins.= A Servian race of civilised mountaineers, inhabiting the rugged district of Montenegro; the only Balkan race which preserved independence and Christianity against the Turkish conquerors. Their history is one of constant warfare with the Turks, and they have thus preserved the primitive virtues of the warrior in great perfection. =Moors.= The ancient Moors, or Mauri, were the inhabitants of the Roman province of Mauretania, roughly including the modern Algeria and Morocco. They were probably of mixed descent, partly Semitic from Arabia, partly Western Hamitic from indigenous sources. In modern times the name is applied (1) to the invaders and conquerors of Spain in the Middle Ages, who were mostly of Arab and Berber stock; (2) to the present inhabitants of Morocco and the Barbary States, of the same stocks, with a large infusion of Sudanese Negro blood. The Moors have always been a turbulent and warlike people, who furnished the most notorious pirates of modern history, thanks to their commanding position on the great highway of sea-borne commerce. =Moquis.= See PUEBLO INDIANS. =Mordvins.= A branch of the Finns (_q.v._), forming small communities on the banks of the Volga. =Mosgus.= See LAKE CHAD GROUP. =Mossis.= See NIGERIAN GROUP. =Mpongwes.= A Bantu Negro race on the Gaboon Estuary in French Equatorial Africa, given to drink and boasting, of little economic value, though once powerful. =Mulattos.= Half-breeds between whites and negroes. =Mundas.= A Kolarian race of Lower Bengal, with possible traces of Negroid blood. =Mundrucus.= See TUPI-GUARANI. =Mundus.= See NILITIC GROUP. =Mushi-Kongo.= Bantu Negroes of Portuguese West Africa, still in an absolutely savage state. =Muskhogean=, or =Appalachian=. A group of North American Indian tribes, formerly occupying the south-eastern corner of the present United States, south of Tennessee, and east of Arkansas. Formerly a powerful confederacy of warlike hunters, they are now extinct or confined to Indian reservations. The chief tribes are Alibamus, Apalachis, Chickasaws, Choktaws, Creeks or Muskhogees, and Seminoles. =Mycenæans.= The inhabitants of ancient Mycenæ, one of the chief centres of prehistoric culture in Greece before the Homeric age. Recent excavations, at Mycenæ itself, at Cnossos in Crete, and other contemporary sites of government, have thrown light on the remarkable civilisation which then existed. The Mycenæans, Cretans, and their kindred peoples were probably a mixed Caucasic race, with affinities to the later Aryan Achæans and to the aboriginal Hamitic Pelasgians; but nothing is yet certainly known of their ethnological place. =Nagars.= See DARDS. =Nagas.= Aborigines of the Naga Hills, in South Assam, semi-savage and formerly accustomed to raid the British provinces; now under British rule. They are of Tibetan stock. =Nahuans=, or =Mexican Indians=. The aboriginal inhabitants of modern Mexico, whose history dates back to the sixth century. The oldest of the Nahuan races was that of the Toltecs, who established a civilisation marked by architectural and artistic monuments still existing, north of the valley of Anahuac. They were followed by the ruder Chichimecs and the Aztecs (_q.v._). Other branches of the same race are the Pipils and the Niquirans of Nicaragua. =Naimans.= (1) See SHARRAS. (2) A tribe of the Middle Horde of the Kazaks. See KIRGHIZ. =Nairs.= A Hindu tribe of Malabar, distinguished by their peculiar marriage customs. They practise polyandry, and a Nair’s property descends not to his own but to his sister’s children. =Namas= or =Namaquas=. A Hottentot tribe of Namaqualand, the true aborigines and the principal representatives of the Hottentots (_q.v._). Scattered in small pastoral groups. =Natchez Indians.= An extinct North American Indian race, formerly inhabiting the region of the Lower Mississippi. =Navajos.= See ATHABASCAN. =Neanderthal Man.= A race of primitive man, represented only by a skull and a few bones found in a limestone cave of the Neanderthal in Rhenish Prussia in 1856. The most ape-like race yet known, and probably the oldest. =Negritoes.= A branch of Ethiopic Man, found in Central Africa, and in the Andamans, the Malay Peninsula and the Philippines, akin to negroes but of smaller stature and more ape-like. Possibly the primitive stock from which the Negroes (_q.v._) were developed. =Negroes.= The most numerous branch of Ethiopic Man, divided into African (Sudanese, Bantu, and Hottentot-Bushman) and Oceanic (Papuan, Melanesian, and Australian) sections. American Negroes are descended from African slaves, mostly of Sudanese origin. See HAYTIANS. =Nempés.= See NIGERIAN GROUP. =Nestorians.= A Syrian race, belonging to the Aramæan stock of the Semitic family, distinguished by a special form of Christian belief, who were driven out of the Roman Empire in the fifth century, and whose descendants now form a special community in the mountain ranges of Kurdistan. They are poor and illiterate. A branch of Nestorians is found in Travancore, where they go by the name of Syrian Christians. =New Guinea Natives.= See PAPUANS. =New Zealanders.= (1) Aborigines [see MAORIS]. (2) White inhabitants of New Zealand, of Anglo-Saxon descent. =Nez Percés.= A tribe of North American Indians, in British Columbia and Idaho, part of whom are well advanced in civilisation. =Niam-Niam.= See AZANDEH. =Nicaraguans.= White natives of Nicaragua, in Central America, of Spanish descent, with Indian and negro elements. =Nicobarese.= Natives of the Nicobar Islands, of Malay blood mixed with that of the Mongolic aborigines. Formerly given to piracy. =Nigerian Group.= A group of Sudanese Negro tribes, all of allied stocks, inhabiting the Niger Delta, the Oil River, Lower Benue, and Niger region, including the Niger Bend. Amongst them are the people of Benin--noted for their vast human sacrifices--the Abo, Nempé, Nupé, Akasa, Qua, Efik, Okrika, Akpa, Mossi, Sienereh, and many other tribes. =Nilitic Group.= Another group of Sudanese Negro tribes, inhabiting the districts of the White Nile, Sobat, and the northern slopes of the Nile-Congo divide. They include the Abaka, Abukaya, Bongo, Shuli, Falanj, Madi, Bari, Nuer, Shilluk, Dinka, Mundu, Rol, Mittu, Krej, and Fertit tribes. They are mainly hard-working agriculturists, from whom the British draw material for excellent soldiery. =Niquirans.= See NAHUANS. =Nogais.= A race of Caucasian Tartars (_q.v._) inhabiting the steppes of the Kuma River; nomadic cattle-breeders. =Normans.= Natives of Normandy, descended from the Norsemen (_q.v._) who settled on the French coast under Rolf the Ganger in the beginning of the tenth century. The history of the Normans, who conquered England and Sicily, is well known. The modern Normans still preserve many signs of their Scandinavian ancestry, which distinguish them from their French or Breton neighbours. =Norsemen= or =Northmen=. A name given in the Middle Ages to the piratical emigrants from Denmark, Iceland, Sweden, and Norway, who descended on the coasts of England, France, Germany, and Southern Europe. They called themselves Vikings. These sea-rovers came, in the first instance, for portable plunder, but in many cases they were tempted by the look of the more fertile lands of the south to make settlements, among which those of the Danes in England and Ireland and of the Norwegians in Normandy, England, and Sicily were the most lasting and important. =Norwegians.= A branch of the Scandinavian stock of the Aryan family. They are probably descended from Teutonic immigrants--perhaps of Gothic race--who entered the Scandinavian peninsula in prehistoric times, and drove out the aboriginal Lapps or Finns. Another theory makes Scandinavia the original home of the Aryans, of whom, on this view, the Norwegians would represent the primitive stock. Their history begins in the ninth century, when a Norwegian kingdom was established by Harold Fairhair. The old Norwegians were extremely warlike and piratical [see NORSEMEN]. Their modern descendants are a peaceful and industrious race, the most simple and democratic people of Europe, who recently threw off the Swedish rule and re-established the ancient Norwegian kingdom. =Nsakkaras.= See WELLE GROUP. =Nuba Group.= A group of Sudanese Negro tribes, occupying Nubia, Dar-Fur, and Kordofan, in the Egyptian Sudan. They include the Furs, Nubas, Nile Nubians, Tumalis, Kargos, Kulfans, Kolajis, and Kunjaras. They are an active and warlike race, in which the primitive Negro blood has frequently been modified by Semitic (Arab) and Hamitic influences. They supply many of our Sudanese regiments. =Nubians.= Ancient inhabitants of Nubia, probably identical with Ethiopians (_q.v._), but modified by the infusion of Negro blood. They established a Nubian kingdom in the Upper Nile basin about the sixth century. =Nuers.= See NILITIC GROUP. =Numidians.= An ancient Hamitic race, inhabiting the district now known as Algeria. They were fine horsemen, warlike, but treacherous, and were conquered by Rome B.C. 46. See BERBERS. =Nupés.= See NIGERIAN GROUP. =Nutkas.= A collective name given to the Indian tribes of Vancouver Island and the adjoining districts of British Columbia. =Obongos.= A Bushman-like race of pygmy Negritoes discovered by Du Chaillu on the western coast of equatorial Africa, physically and mentally degenerate. =Ojibbeways.= See ALGONQUIAN. =Okrikas.= See NIGERIAN GROUP. =Olkhonese.= A tribe of Buriats (_q.v._) inhabiting the district of Lake Baikal. =Omaguas.= See TUPI-GUARANI. =Omahas.= See SIOUAN. =Onondagas.= See IROQUOIAN. =Opata-Pima.= A group of Central American Indian races, allied to the Nahuan group (_q.v._), but of lower mental and physical type. It includes the Cora, Yuma, Papago, Tarahumara and Tepeguana tribes. =Orang-Benua, Orang-Lauts.= See MALAYS. =Ordos.= See SHARRAS. =Orochs.= A nomadic tribe of the Siberian Tunguses (_q.v._). =Osages.= See SIOUAN. =Oscans.= A primitive Italic race inhabiting Campania, who were conquered by and amalgamated with the Samnites (_q.v._) in the fifth century, B.C. Their language was a ruder form of Latin. =Osmanlis.= See TURKS. =Ossets.= An isolated Aryan race inhabiting the Central Caucasus, and differing in language and customs from their Caucasian neighbours. They are probably allied to the Iranian stock, though some suppose them to be descended from Gothic settlers. =Ostrogoths.= See GOTHS. =Ostyaks.= A Ugrian race of Mongolic physical type, allied to the Samoyedes (_q.v._), inhabiting the Obi basin in Western Siberia. They are mainly nomads, hunters and reindeer breeders. They are kind, gentle and honest, and show considerable artistic power. =Otoes.= See SIOUAN. =Otomis.= An Indian race of Mexico, assumed on linguistic grounds to represent the oldest of American Indian stocks. =Ottomans.= See TURKS. =Ovaherero.= See HEREROS. =Ovampos.= The chief Bantu Negro race of German South-west Africa, tall and well-proportioned, with regular features--a fine Negro type. They are industrious agriculturists, given to raiding and inter-tribal warfare. =Oworos, Oyos.= See YORUBAS. =Pampas Indians.= See PUELCHES. =Pangasinans.= A semi-civilised Malayan race in the Philippine Islands. =Papagos.= See OPATA-PIMA. =Papuans.= The savage aborigines of New Guinea and the neighbouring islands of the Torres Strait and East Malaysia. They belong to the Oceanic division of Ethiopic Man, and are allied to the African Negro, though they stand at a somewhat higher intellectual level. They are of Negroid physical type, characterised specially by their mops of frizzy hair; colour, a sooty brown to black, with projecting jaws, thick lips and retreating foreheads; nose sometimes flat, but oftener hooked and of Jewish appearance. The race has probably been modified by Malayan and Polynesian intermixture. Probably the Melanesians and the Australian aborigines are closely related to the Papuans. They are a fierce and treacherous race, hostile to strangers, and given to cannibalism and head-hunting. They show much agricultural skill, and in some cases are susceptible of European civilisation. =Paraguay Indians.= See TUPI-GUARANI. =Parsees.= Followers of Zoroaster, of Persian descent, who have settled in India, chiefly near Bombay, where they have become one of the most thriving sections of the community, owing to their marked ability for commerce. A small remnant of Parsees, known as Guebres, is still to be found in Persia itself. =Parthians.= A warlike people of the ancient world, inhabiting a district of Northern Persia. They seem to have been of Scythian (_q.v._) descent, and were noted for their habit of fighting on horseback and discharging their most fatal arrows whilst in pretended flight. Under Mithridates (171-138 B.C.), the Parthians became supreme in Persia, and afterwards warred for long successfully with the Romans. =Patagonians= or =Tehuelches=. Natives of the most southerly region of the American continent, noted for their great stature, in many cases approaching the gigantic. They are one of the physically strongest races of the earth, of a yellowish brown colour, with well-formed and regular features. They are nomadic tribes of Araucanian (_q.v._) descent, who live by fishing and hunting; and peacefully disposed to strangers. =Pathans.= See AFGHANS. =Payaguas.= A South American Indian race, in the Argentine, whose wealth of silver ornaments gave a name to the Rio de la Plata. =Pawnees.= A brave warlike tribe of North American Indians, akin to the Shoshonean group (_q.v._) and formerly settled in Nebraska. =Pechenegs.= An ancient Mongolic race of Turki stock, a branch of the Kipchaks (_q.v._). =Pelasgians.= The pre-Aryan inhabitants of Greece, apparently the aborigines of that country, who were dispossessed by the Aryan Hellenes. Little or nothing is known of their racial characteristics and affinities; but the excavations recently made at Mycenæ, Knossos, etc., show that they had reached a high stage of civilisation in prehistoric times on the Ægean coast. Probably a branch of the Western Hamitic family, resembling Berbers (_q.v._) in physical type. See MYCENÆANS and ETRUSCANS. =Permians.= A branch of the Finnish race, inhabiting the district of Perm in Russia, and closely resembling the Karelians (_q.v._). =Persians.= The ancient Persians were the main branch of the Iranian stock of the Aryan family, a civilised and warlike nation, who taught their sons “to ride, to shoot with the bow, and to speak the truth.” They reared a great empire under Cyrus (B.C. 537) and his successors, which was destroyed by Alexander the Great and divided in 324 B.C. The modern Persians, known as Tajiks, and as Tats on the west of the Caspian, are the descendants of the ancient Persians with a considerable admixture of alien blood, due to a long period of Arab and Turkish domination. They present a fine Aryan type, however, and are cultivated and commercial, though not warlike. =Peruvian Indians.= See INCAS. =Peruvians.= White natives of Peru, partly of pure Spanish descent, partly crossed with Indian blood. =Philippine Islanders.= The natives of the Philippines belong to three distinct races--Negritoes, Indonesians and Malays. The Negritoes are known as Aetas (_q.v._). The Indonesians are confined to the island of Mindanao; they are light-skinned, tall and well-developed physically. Their chief tribe is that of the Igorrotes. The Malays are brown-skinned, with black hair and flat noses, being crossed with Negrito blood. Their chief tribes are the Visayans, Tagalogs, Bicols, Ilocanos, Cayagans, Pangasinans and Pampangas. These are all Christianised and fairly civilised. The interior is occupied by wild and savage tribes of similar race, and by the dwarfish and nomadic Negritoes. Many of these tribes practise head-hunting, cannibalism, and human sacrifices. The more civilised tribes, with the Spanish-Indian half-breeds, known as Filipinos, are turbulent and lawless, the source of much trouble to the new American as to the old Spanish rulers. =Philistines.= An ancient race inhabiting the Mediterranean seaboard to the south-west of Judæa, who warred much with the Israelites, and were finally subdued by them. They were probably a Canaanitish people, belonging to the Semitic family; but some regard them as an immigrant Hamitic race, perhaps related to the Cretans or Pelasgians. The assumed inferiority of their culture to that of the Israelites has given rise to the modern use of “Philistine” as a term of reproach. =Phœnicians.= The greatest seafaring and trading nation of ancient times, and the earliest of Mediterranean sea-powers. A branch of the Canaanite stock of the Semitic family, they inhabited the Mediterranean coast between Latakia and Acre, their chief cities being Tyre and Sidon. They possessed a remarkable polytheistic religion, disfigured by human sacrifices. They were an inventive race, to whom we owe glass and Tyrian purple. They seem to have entered Phœnicia from the direction of the Red Sea in prehistoric times, and were at first subject to Egypt, but about 1300 B.C. reared a great maritime empire, which endured for nearly a thousand years and was destroyed by Alexander the Great. They were the great traders of the ancient world, and carried on a commerce which ranged from Cornwall to Ceylon and Senegal. The Carthaginians (_q.v._) were a colony of Phœnicians. =Phrygians.= An ancient pastoral people of Asia Minor, closely related to the Armenians (_q.v._), who were absorbed by the Persians in the sixth century B.C. =Picts.= The aborigines of ancient Scotland, a short, round-headed, dark race, probably a branch of the Iberian stock of the Western Hamitic family, and thus closely related to the Basques (_q.v._). The Picts were a wild and warlike race, who harassed the Roman province of Britain, and were exterminated by the invading Scots from Ireland in the early part of the Christian era. The whole Pictish problem is still unsolved by ethnologists, some of whom hold that the Picts were a Celtic race, allied to the modern Welsh or to the Scottish Highlanders of to-day. =Picuris.= See PUEBLO INDIANS. =Pipils.= See NAHUANS. =Pitcairn Islanders.= Half-breed descendants of Englishmen (the mutineers of the “Bounty”) and Tahitian women. A peaceful and idyllic race. =Pocomans, Poconches.= See MAYA-QUICHÉ. =Poles.= A stock of the Western Slavonic family, originally dwelling between the Vistula and the Oder. In the tenth century Poland became an independent European Power, and remained an elective kingdom down to its partition in the eighteenth century between Russia, Austria and Prussia. The Polish peasantry have always been industrious and successful agriculturists, whilst the nobility were turbulent and warlike. The Poles who live under Austrian and German rule are fairly contented, but those of Russian Poland have carried on a long and often bloody series of struggles for liberty. Of late years, Russian Poland has become a manufacturing country, under German influence. The Poles have a considerable literature, and are eminently musical. =Polynesians.= The chief stock of the Indonesian (_q.v._) family, the tall, brown-skinned race of Caucasic type who inhabit the chief islands of the Eastern Pacific, and are generally known as South Sea Islanders. Their chief races are the Maoris (_q.v._) of New Zealand, the Marquesans, Tahitians, Tongans and Samoans, besides the natives of Easter, Gambier, Hervey, and other smaller islands. They are of tall stature--only surpassed by the Patagonians--muscular frame, regular and often handsome features, with brown skins, square jaws, and broad skulls. They probably originated in Malaysia, where they are still represented by the Battaks of North Sumatra, some Dyak races, and certain tribes of the Philippines and Gilolo. They are a gay, pleasure-loving people, formerly addicted to cannibalism, but otherwise of pleasing manners, and are now rapidly acquiring civilisation, though their numbers are everywhere decreasing under the influence of European manners and diseases. =Poncas.= See SIOUAN. =Portuguese.= Natives of Portugal, a mixed race, probably of Iberian or Basque origin, with later Celtic elements. After falling successively under Roman, Visigothic, and Saracen dominion, they formed an independent kingdom in the twelfth century. The early Portuguese were enterprising seamen, who contributed largely to the exploration of the world, and founded many colonies in Africa, which they still possess. Brazil is their chief American settlement, now independent. =Provençals.= Natives of Provence, in the South of France. Their primitive Ligurian (_q.v._) stock was modified by many successive influences, such as the Greek colonists, who founded Marseilles, the Roman settlers in the Provincia (Provence), and, later, Gothic and Saracen invaders. The Provençals are a gay, impulsive and pleasure-loving people, markedly distinct from the more staid and industrious inhabitants of Northern France. =Pruczi=, or =Old Prussians=. See LETTIC. =Prussians.= The earliest inhabitants of Prussia were Slavonic tribes [see LETTIC]. The modern Prussians, the dominant race of the German Empire, belong to the High German branch of the Teutonic stock. [Illustration: WOMEN OF THE NUPÉ TRIBE IN NIGERIA The Nupé tribe is a family belonging to the Nigerian group of Sudanese Negroes. They inhabit chiefly the town of Lokoja, in West Africa. [See under Nigerian group]. ] [Illustration: THE AINUS, PROBABLY THE ORIGINAL INHABITANTS OF JAPAN The Ainus are a declining race, now confined to a small area in the Far East. They have, as is seen in this picture, handsome features and an abundance of hair. [See page 312]. ] =Pueblo Indians.= A semi-civilised race of North American Indians, dwelling in New Mexico and Arizona. They inhabit “pueblos,” or huge houses, often large enough to contain a whole tribe under one roof. They possess interesting religious and social customs, much studied by anthropologists. Their chief tribes are the Zunis, Teguas, Taos, Picuris, and Tusayas. The Moquis of Arizona are closely related to them. =Puelches=, or =Pampas Indians=. A strongly-built, dark-skinned race of South American Indians, who inhabit the great plains or pampas from the Saladillo to the Rio Negro in Argentina. They are expert horsemen, from whom the Gauchos (_q.v._) are derived. =Punjabis.= Natives of the Punjab, in North-West India, mostly Jats and Sikhs (_q.v._) belonging to the Hindu stock of the Aryan family. An agricultural and warlike people. =Puntis.= See CHINESE. =Pygmies.= Dwarfish Negrito races of Central Africa, long considered to be mythical, but now well known to ethnologists. They include the Akkas and Wochuas of the Welle Basin, the Obongos of the Gaboon, the Batwas of South Congo, etc. In very early times they were known by repute to the Egyptians--on whose monuments they appear in the thirty-fourth century B.C.--and the Greeks. They live by the chase in the Central African forests, and use poisoned arrows. Other small races, such as the Bushmen, Lapps, Kalangs, Samangs, etc., have contributed to the fame of the Pygmies. =Quas.= A Sudanese Negro tribe on the Ivory Coast, belonging to the Nigerian group (_q.v._). =Quapaws.= See SIOUAN. =Queahs.= See LIBERIAN GROUP. =Quichés.= A race of Central American Indians in Guatemala, rivalling the Aztecs in the possession of an ancient civilisation and a curious mythology. See MAYA-QUICHÉ. =Quichuas.= See INCAS. =Rajputs.= The predominant race of Rajputana, in Central India, belonging to the Hindu stock of the Aryan family. They are a proud and warlike aristocracy of soldiers and landowners, who rule many native states, of which Jaipur, Jodhpur and Udaipur are the most important. =Ramas.= See LENCAN. =Redskins.= A term given in common parlance to North American Indians, from their colour. =Rejangs.= A Malayan race of Sumatra, akin to the Achinese (_q.v._). =Rols.= See NILITIC GROUP. =Romans.= The most powerful and warlike, and in every sense the greatest race of ancient Europe, who acquired the dominion of the Western world, and laid the foundations of modern civilisation. The city of Rome was founded by Alban shepherds, of Latin (_q.v._) race, in the eighth century B.C. Oscan, Sabine, Samnite, and Umbrian (_q.v._) elements were added to the original stock, and thus the great Roman character was moulded. Rome later extended her power over the whole of Italy, and then over the whole of the known world. =Romance Races.= See LATIN RACES. =Romansch.= Natives of the Grisons in Switzerland, speaking a Romance dialect, and probably of Italic race. =Roumanians=, or =Vlachs=. Natives of the modern Roumanian kingdom, the leading Balkan State, composed of the older principalities of Wallachia and Moldavia, which were long subject to the Turks. The Vlachs (Wallachs, a name akin to our Welsh) are probably descended from the Latin-speaking inhabitants of the ancient Roman province of Dacia, a tribe of Thracian descent, which was subjugated by Trajan in the second century. They have preserved their language, but their blood has been mingled with that of numerous conquerors--Goths, Huns, Slovenians, Albanians, Turks, etc. The Roumanian peasantry are a hardy and thrifty race, retaining their old warlike traditions. =Rucuyennes.= See CARIBS. =Russians.= The chief of the Slavonic races inhabiting European Russia, and divided into Great, White, and Little Russians. The physical distinction between these races is attributed to the mixture of the primitive Russian stock respectively with Finnish, Lithuanian, and Turkish blood. The original Russians belonged to the Slavonic stock of the Aryan family, and seem to have been settled in prehistoric times between the Danube, the Elbe, and the south coast of the Baltic. Thus they must have entered Russia from the west in the early centuries of our era. There they conquered and drove out or assimilated the aborigines of Northern Mongolic (Finno-Turkish) stock, and established a number of small states, agricultural in character, which long suffered from Tartar invasion, notably that of the Golden Horde [see KIPCHAKS], and were gradually moulded into a single kingdom, with Moscow for its capital. Modern Russia, with its vast Asiatic dependencies, is one of the greatest Empires in the world, but it is in a state of transition, and its civilisation is consequently backward. The Russian peasants are very patient, industrious, and thrifty. When well led, they are admirable soldiers. Their chief occupation is agriculture. =Ruthenians.= A branch of the Little Russian race, who inhabit the district of the Carpathians in Galicia and Hungary; poor, but hardy cultivators of the soil. =Sabæans.= See HIMYARITES. =Sabines.= An ancient Italic race, who inhabited the district between the Central Apennines--their ancestral home--and Rome. The Samnites were their descendants or near kinsmen, and the Umbrians were less closely related to them. When Rome was founded there was a strong Sabine element in its population, as indicated by the story of the Rape of the Sabine Women, and the statement that several of the early kings of Rome were of Sabine blood. The Sabines and Samnites warred against Rome for many years, but both were ultimately subdued and incorporated in the Roman State. =Sac Indians.= See ALGONQUIAN. =Sakais=, or =Samangs=. An aboriginal Negrito race of the Malay Peninsula; a wild and uncivilised people, with black skins and woolly hair, often approaching the ape-like in physical development and intelligence. =Sakalavas.= One of the principal groups of the Malagasy tribes, inhabiting the west coast of Madagascar; of mixed Malay and negro blood, and akin to the Hovas (_q.v._). =Salish.= See FLATHEADS. =Samangs.= See SAKAIS. =Sambos=, or =Zambos=. Half-breeds sprung from Negro and Indian parents. =Samnites.= See SABINES. =Samoans.= A Polynesian (_q.v._) race, of fine physical development, lazy and pleasure-loving, inhabiting the Samoan group of islands. =Samoyedes.= A Finno-Ugrian race, inhabiting the Obi basin in Siberia, once widely spread over the extreme north of Europe and Asia. They are short and dark haired, with Mongolic features, brave and honest, live by hunting and fishing, and are still in the Stone Age. =Samsams.= A mixed Malayo-Siamese race, forming a large part of the population of the Malayan States of Kedah and Ligor. =Santals.= A negro-like aboriginal tribe of Orissa in India, agriculturists, of the Kolarian family (_q.v._). =Saracens.= A term applied in the Middle Ages to the Moslem enemies of Christendom, especially to the nomadic Arabs and Bedouins of the Syrian deserts. =Saras.= See LAKE CHAD GROUP. =Sarakolés.= See MANDINGAN. =Sards=, or =Sardinians=. The aboriginal inhabitants of Sardinia, probably of the Western Hamitic family, akin to the Iberians or Ligurians (_q.v._). The modern Sardinians are descended from this race, with considerable admixtures of alien blood from the Carthaginian, Roman, Saracen, Spanish and Italian owners of the island in successive periods. =Sarmatians.= An ancient nomadic and warlike people, probably akin to the Scythians (_q.v._), who roamed over the wide plains of Eastern Europe. Fine horsemen. They were destroyed by the Goths in the fourth century, and disappeared from history. =Sassaks.= Natives of Lombok in the Sunda Islands, of Malayan race. =Savoyards.= Natives of Savoy, originally a short, round-skulled, dark race, akin to the Auvergnats (_q.v._), now largely mingled with Teutonic blood. =Saxons.= (1) The Old Saxons originally inhabited the estuary of the Elbe and the neighbouring islands. They were a warlike race, of Low German stock, whose name is said to be derived from the “Saxes,” or heavy knives which they used in war. They were one of the most adventurous of Teutonic races, and made many piratical and colonising excursions, of which the most important was their settlement in Britain in the fifth century, where they united with the Angles (_q.v._) to lay the foundation of the modern English people. (2) The Saxons who remained on the Continent gradually extended their dominion till it reached modern Saxony. Under Charlemagne the Saxon power was subordinated to that of the Franks. Saxony later became an independent duchy, which is still one of the chief States of the German Empire. The modern Saxons are less adventurous than their ancestors, very industrious, and successful in agriculture and industry, and make excellent soldiers. =Scandinavians.= A main stock of the Aryan family, sometimes classed as a branch of the Teutonic stock, including the Icelanders, Norwegians, Danes and Swedes, as well as the old Norsemen and Normans (_q.v._). Some ethnologists regard them as the original stock of the Aryan family. They are tall, blue-eyed, fair-haired, warlike, and good sailors and colonists. =Scots= or =Scotch=. (1) The ancient Scots were a Celtic race, belonging to the Goidelic or Q Celts (_q.v._), originally settled in Ireland--the ancient Scotia--whence they made settlements in the fifth century in modern Scotland, to which they gave their name. They were gradually driven back into the Highlands by Anglo-Saxon, Norman and Danish invaders, and are now represented by the Highlanders (_q.v._) or Gaels. (2) The modern Scots, or Lowland Scots, are mainly of Anglo-Saxon race, modified by Norman, Danish, and Flemish elements. They are one of the finest and most hardy and industrious races in the world, equally successful in the arts of war and peace. =Scythians.= An ancient nomadic and warlike race, found in the seventh century B.C. on the vast plains of South-eastern Europe, where they lived by cattle-breeding and raiding. They dwelt in tent-covered waggons, fought on horseback with bows and arrows, and made drinking-cups of their enemies’ skulls. Their origin is in dispute. Some regard them as a Mongolic race, which was modified by association with Aryan races, and others as an Aryan stock; their kinsmen, the Sarmatians (_q.v._), were almost certainly Aryans. They made several incursions into Asia, where they conquered a large tract of Northern India and established a kingdom which lasted till about the fourth century A.D. The Rajputs and Jats (_q.v._) are sometimes held to be their descendants. =Selengese.= See BURIATS. =Seljuks.= A warlike Turkish people who were settled on the Jaxartes in the eleventh century and afterwards founded a considerable empire in Western Asia. See TURKS. =Seminoles.= See MUSKHOGEAN. =Semites.= An important family of Caucasic Man, who probably originated in North Africa, from a similar stock to that of the Hamites. They are characterised by fine regular features, large aquiline noses, black eyes and hair, white skins, long skulls and square jaws. They are very intellectual, though less practical than the Aryan type; poets, prophets, and dreamers, rather than men of action. They have given the world its two greatest religions--Christianity and Islam. Their chief divisions are Assyrians, Aramæans, Canaanites, Arabs and Himyarites (_q.v._). In the modern world they are best known from the ubiquitous Jews (_q.v._). =Seneca Indians.= See IROQUOIAN. =Serbs.= See SERVIANS. =Serers.= Sudanese Negroes inhabiting Senegambia in the Cape Verde district. They are the tallest of Negro races, with herculean frames, and are akin to the Wolofs (_q.v._) =Servians=, or =Serbs=. A race of Southern Slavonic stock, now inhabiting Servia. They were at first identical with the Croats (_q.v._), and seem to have originated in the Carpathian district, whence they migrated into the Balkan peninsula in the seventh century. The Serbs then separated from the Croats, and in the twelfth century founded a powerful Servian kingdom, which was conquered by the Turks in the fifteenth. The Servians recovered their independence in 1830, under Milosh Obrenovitch. The Servians are a well-built race, proud and martial in temperament, quick-tempered and prone to deeds of violence, as their recent revolution witnessed. =Shangallas.= A mixed negroid race of the Abyssinian slopes. Sudanese Negroes with a Hamitic infusion. =Shans.= Natives of the independent Shan States, lying to the north of Siam. They are identical with the Laos, and closely related to the Siamese (_q.v._). They belong to the Indo-Chinese stock of the Southern Mongolic family, and are probably descended from an aboriginal race of China, which appeared on the Upper Irawadi about 2,000 years ago. They are a peaceful, pleasure-loving people, mainly agricultural, but not unwarlike. They have a sallow skin and Mongoloid features. =Sharras=, or =Eastern Mongols=. A branch of the Mongol stock of the Northern Mongolic family. They are a nomad, tent-dwelling, pastoral race, who roam over the great steppes of Central Asia. They include the Khalkas, north of the Gobi Desert, the Tanguts of Northern Tibet, the Chakars, Barins, Durbans, Uruts, Naimans, and Ordos south of the Gobi. They are descended from the older Mongols (_q.v._), whom they resemble in physical type. =Shawnees.= See ALGONQUIAN. =Shilluks.= See NILITIC GROUP. =Shoshonean.= A group of North American Indian tribes, all belonging to the Shoshone or Snake family, formerly occupying Idaho, Utah, and Wyoming, with neighbouring districts. They include the Shoshones or Snakes, Bannocks, Comanches, Utahs, and Mokis. With the exception of the warlike Comanches, they are a peaceful race, who have received the white invaders with friendship. =Shulis.= See NILITIC GROUP. =Siamese.= Natives of Siam, belonging to the Indo-Chinese stock of the Southern Mongolic family. They are closely related to the Shans (_q.v._). They are of medium height, olive complexion, with slightly flattened noses, prominent lips, and black hair. They are a peaceful and indolent race, who have recently shown promise of assimilating Western civilisation. Their blood is largely mixed with Chinese and Malay. Siam is still independent, forming a buffer state between British and French possessions. =Siberian.= A stock of the Northern Mongolic family, including the Chukchi, Koryak, Kamchadale, Gilyak, and Yukaghir tribes (_q.v._). =Sicani, Siculi.= See SICILIANS. =Sicilians.= The primitive inhabitants of Sicily were the Sicani, probably a Hamitic race allied to the Ligurians (_q.v._). They were followed by the Siculi, an Aryan race of Italic stock, who crossed from Italy about 1000 B.C. They were civilised and modified by Phœnician, and especially Greek settlers, with later Norman and Saracen influences. Of all these elements the modern Sicilians are compounded. They are a handsome, industrious, and amiable race, but turbulent, lawless, given to blood-feuds and brigandage. =Sienerehs.= See NIGERIAN GROUP. =Sikhs.= A powerful and warlike race of Northern India, united by a common religious faith, dating from the eighteenth century, and mainly of Jat (_q.v._) descent. Under Ranjit Singh, at the beginning of the eighteenth century, they reared a formidable military power in the Punjab, which was conquered by the British in 1846-1849. The Sikhs contribute many of the best and most trustworthy troops to the Indian Army. =Silurians.= A dark, round-skulled, short race who inhabited South Wales and the neighbouring districts of England in Roman times. They were probably of Iberian stock, related to the ancient Picts and modern Basques. =Sindis.= Natives of Sind in North-West India, of Hindu descent. =Singphos.= A wild, daring hill-tribe of Tibetan stock bordering on the Assam valley, formerly given to raiding, but now peaceful agriculturists. The Chins of the Arakan uplands are probably an identical race; they are still predatory. =Sinhalese.= See DRAVIDIANS. =Siouan.= A numerous and formerly powerful group of North American Indians, inhabiting the western prairies between the Mississippi and the Rocky Mountains. Their chief tribe was the Sioux or Dakotas, warriors of fine physique, courage, and military skill, who long maintained a successful resistance against the white settlers. Other allied tribes were the Assinaboins, Omahas, Poncas, Kaws, Osages, Quapaws, Iowas, Otoes, Missouris, Winnebagos, Mandans, Minnetarees, Absarakas or Crows, Tutelos, and Catawbas. =Sioux=, or =Dakotas=. See SIOUAN. =Siryanians.= A tribe of Ugrian Finns, dwelling on both sides of the Northern Urals, resembling the Samoyedes (_q.v._), except in their white colour and fair hair, probably due to a mixture of Slavonic blood. See FINNO-UGRIAN. =Slavonic Races=, =Slavs= or =Slavonians=. A main stock of the Aryan family, occupying the greater part of Eastern Europe, and formerly extending as far west as the Elbe. Many ethnologists consider them to be the primitive Aryan stock. They are a peaceful and industrious agricultural and pastoral race, broad-skulled, with fair hair and blue eyes; though the primitive type has been much modified by intermixture of blood, especially with Mongolic races, who have imprinted a Tartar character on many Slavonic physiognomies. The Slavs are divided into Eastern (Russians and Ruthenians), Western (Czechs and Slovaks, Poles and Wends or Sorbs), and Southern (Bulgarians, Servians, and Croats, Dalmatians, Slovenians, and Montenegrins). See under these heads. =Slovaks.= See CZECHS. =Slovenians.= A branch of Southern Slavonic stock, inhabiting Styria, Carinthia, and adjoining districts. =Solimas.= See TEMNÉ GROUP. =Somalis.= An Eastern Hamitic race of Somaliland in North-East Africa. They are a pastoral people, of good physique, handsome features, and light-brown colour, warlike and independent. The original Hamitic stock--closely akin to that of the Gallas (_q.v._)--is modified by Semitic and Negro blood. They make excellent soldiers and servants. =Sonrhays.= A Negro race of the Middle Niger, in whom the Sudanese stock is modified by Arab and Berber elements. =Sorbs.= See WENDS. =Soyots.= A tribe of Ugrian Finns, mixed with Tartar blood, in the Sayan Mountains of South Siberia. See FINNO-UGRIAN. =Spaniards=, or =Spanish=. The earliest known race of Spain was the Hamitic Iberians (_q.v._), now represented by the Basques. They were modified by Celtic invasions, which gave birth to the Celt-Iberian races of Central and Western Spain, who struggled so long against the Roman arms, by which they were finally subjugated and further modified. In the fifth century the Vandals and Visigoths (_q.v._) invaded Spain, and founded a Gothic monarchy, which fell before the Saracens in 711. The Visigothic refugees in the northern mountains gradually recovered the country, and the kingdoms of Leon, Navarre, Castile, and Aragon were ultimately united into a single state. The modern Spaniards are thus of mixed race, in which the Iberian and Visigothic are the predominant elements. They are haughty, brave, and warlike, by which qualities they once owned the greatest power in Europe. But they are turbulent and lacking in political skill, so that Spain has decayed. There are now signs of a return to prosperity. =Spanish Americans.= White natives of Central and South American States, except Brazil. =Spartans.= Natives of Sparta, the greatest state of ancient Greece after Athens, of Dorian stock, eminently warlike and patriotic, but wanting in art or literature. =Sudanese.= Full-blooded Negroes inhabiting the Western, Central, and Eastern or Egyptian Sudan--_i.e._ most of Africa north of the Victoria Nyanza. They are black in colour, with woolly hair, projecting jaws, long skulls, broad, flat feet and projecting heels, and form one of the main divisions of Ethiopic Man. They are less intelligent and susceptible of civilisation than the Bantus (_q.v._), in whom the Negro blood is modified by Hamitic or Semitic admixtures. They are mostly of strong physique, warlike and predatory, fond of music and bright colours, with the most elementary notions of art and religion. They may be divided for convenience into several racial groups (_q.v._), such as Wolof, Felup, Toucouleur, Mandingan, Temné, Nigerian, Nilotic, Liberian, Lake Chad, Wadai, Welle, Nuba, and Nilotic, besides the Tshi, Ga, Ewe, and Yoruba peoples of the Guinea district. =Suevi.= See SWABIANS. =Sundanese.= Natives of the Sunda Islands, of Malayan stock, closely allied to Javanese (_q.v._). =Susus.= See MANDINGAN. =Sutughils.= See MAYA-QUICHÉ. =Swabians.= Natives of Swabia, an ancient duchy occupying the south-western part of the modern German Empire; descended from the ancient Suevi, with whom the Alemanni (_q.v._) were amalgamated. A strong, large-boned, and good-humoured race of High German stock. The Alsatians are closely allied to them. =Swahilis.= Natives of Zanzibar and the adjoining mainland, Bantu Negroes, with a strong infusion of Arab blood, which has made them superior in intelligence and enterprise to the average negro. They play a large part in the commerce of East Africa, and their language--Ki-Swahili--is the principal medium of communication throughout the part of Africa between the Equator and the Zambesi. =Swazis.= Natives of Swaziland, a native state on the south-east of the Transvaal. A cross between Zulus and other Kafirs, they are industrious and warlike. =Swedes.= Natives of Sweden, a branch of the Scandinavian stock. They seem to have been originally a Teutonic race, who entered Northern Sweden about 3,000 years ago, and drove out the aboriginal Lapps and Finns. The inhabitants of Southern Sweden were called Goths, and may have been the ancestors of the Teutonic Goths. In time they amalgamated with the Swedes, and formed one nation, which has been an independent kingdom through most of the Christian era. The Swedes are warlike, and successful in commerce and industry; they make good sailors, and possess a considerable literature. =Swiss=, or =Switzers=. The prehistoric inhabitants of Switzerland were the unknown builders of the lake dwellings. At the dawn of history, in Cæsar’s time, the country was largely occupied by a Celtic race, the Helvetii. Later, Switzerland was invaded by Teutonic races of High German stock, Alemanni, Burgundians, etc. The modern Swiss are mostly descended from these races; there is also a considerable mixture of French, Italic and Romansch elements. The Swiss have always been a warlike race, who preserved the independence of their mountainous country through all ages, and in earlier times furnished excellent mercenary soldiers to foreign armies. They are now very industrious and successful in many arts and crafts, such as watchmaking, wood-carving, hotel-keeping, etc. They are a simple and handsome race, possessing in full measures the virtues of the mountaineer. =Syrians.= The ancient Syrians were a branch of the Aramæn stock of the Semitic family, and the modern Syrians are their descendants, with some Arab and Turkish elements added. They are tall, with white skins and dark complexions, black eyes and hair, often very handsome, and approaching the Jewish type. They are not warlike, but succeed in commerce. =Tacullis.= See ATHABASCAN. =Tahitians.= Natives of Tahiti, of Polynesian stock; pleasure-loving and polite, but immoral and untrustworthy; now civilised but formerly noted for their cruelty. =Taipings.= The Chinese rebels who attacked the dynasty from 1850 to 1864. =Tajiks.= See PERSIANS. =Talaings.= An Indo-Chinese race who preceded the Burmese in the Irawadi Delta, and founded a state of which Pegu was the capital. They were subjugated by Burmese in the eighteenth century. =Talamancas.= Wild hunting Indians, perfectly uncivilised, who occupy the forest-covered Atlantic slopes of Costa Rica. =Tamils.= Natives of Northern Ceylon and the Indian Carnatic. See DRAVIDAS. =Taos.= See PUEBLO INDIANS. =Tanguts.= Nomadic Mongols of Northern Tibet. See SHARRAS. =Tarahumaras.= See OPATA-PIMA. =Tarascans.= A group of Indian tribes inhabiting the province of Michoaca in Mexico. =Tartars= or =Tatars.= The modern Tartars are inhabitants of the Russian Empire, belonging to the Turki stock of the Northern Mongolic family. They are divided into various geographical subdivisions, such as the Kazan, Astrakhan, Crimean (or Krim) Caucasian and Siberian Tartars. The name has no definite ethnical significance. The Tatars--a Manchu word meaning “archers” or “nomads”--were Mongol tribes who were first so named in the ninth century. They formed a large part of the hordes of Genghiz Khan [see MONGOLS] and stood in the van of the mediæval Mongol incursions into Europe, whence they attracted an attention out of proportion to their importance. Europeans called them Tartars, confusing the name Tartar with the Greek Tartarus or Hell. See TURKI. =Tasmanians.= The extinct aborigines of Tasmania, akin to the Australians (_q.v._), but of a still lower Oceanic Negro type. They held a place at the very bottom of humanity, alike in physique, intelligence and culture, being still in the early Stone Age; savage, untamable, and degraded. =Tatars.= See TARTARS. =Tats.= See PERSIANS. =Tavastians.= A branch of the Baltic Finns, with thick-set figures, small blue eyes, light hair, and white skins, probably the consequence of an admixture of German blood with the original Finnish stock. They inhabit central Finland. =Tazis.= See TUNGUSES. =Teguas.= See PUEBLO INDIANS. =Tehuelches.= Another name for the gigantic Patagonians (_q.v._) of South America. =Telugus.= See DRAVIDIANS. =Tembus=, =Amatembu=, or =Tambukies=. A group of Kafir (_q.v._) tribes in Tembuland, to the north of the Kei River in Cape Colony. Formerly warlike and troublesome, now settled to agriculture and subjected to British rule. =Temné Group.= A group of Sudanese Negro tribes, inhabiting the Sierra Leone district of West Africa, including the Temnés or Timnis, Kissis, Sherbros, Gallinas, Bulloms, Solimas, Limbas, and Mendis. =Tepeguanas.= See OPATA-PIMA. =Teutons.= An important stock of the Aryan family, inhabiting England and the Scottish Lowlands, with the United States and British Empire, Germany, Holland, and parts of Austria and Switzerland, Denmark, Norway, and Sweden. The Teutonic races are divided into Low German and High German divisions, to which some add, but others do not, Scandinavians. =Thlinkits.= A race of North American Indians inhabiting the Pacific coast from Mount St. Elias to the Simpson River, and the adjacent islands. They live chiefly by fishing and hunting. =Thos.= An Indo-Chinese race of Lao descent [see SHANS], in the north of Tongking. =Thracians.= The ancient inhabitants of Thrace, on the west of the Black Sea. Their origin is dubious, but they are generally assumed to have belonged to the Aryan family, and been related to the Teutons and the Greeks. They were wild hill tribes, who acquired in later days a certain amount of Roman culture and spoke the Latin language. There is some probability that they were the ancestors of the Vlachs or Roumanians (_q.v._). =Thuringians.= A High German tribe inhabiting Thuringia in the fifth century, probably a branch of the Suevi (_q.v._). Now merged into the modern Saxons. =Tibetans=, or =Bod-Pa=. Natives of Tibet, forming the Tibetan stock of the Southern Mongolic family, and allied to the minor races of Lepchas, Baltis, Ladakhis, etc. (_q.v._). The Tibetans are akin to the Burmese, with Mongolic features, broad-shouldered and muscular. They are a secluded and archaic race, with many curious customs, such as polyandry. Their religion is full of elaborate ceremonials, and the land abounds in monasteries. =Tibbus.= A race inhabiting the oases of the Sahara, intermediate between Berbers and Negroes; perhaps descended from the ancient Garamantes (_q.v._). =Timnis.= See TEMNÉ GROUP. =Tinné=, or =Tinney=. See ATHABASCAN. =Tobas.= A warlike and predatory race of South American Indians on the Rio Vermejo in Bolivia. =Tocantins.= See TUPI-GUARANI. =Todas.= An isolated group of Caucasic race inhabiting the Nilgiri Hills, and distinguished from the neighbouring Dravidian tribes by their fine physique and regular features of Caucasic type; a dying race. =Togos.= See EWE. =Toltecs.= The oldest of Nahuan (_q.v._) races, who established a semi-civilised State in Mexico before the Aztecs. =Tongans.= See POLYNESIANS. =Tongas=, or =Amatonga=. A Kafir race of peaceful agriculturists, occupying Tongaland, to the north of Zululand. =Tonkinese.= A branch of the Annamese (_q.v._), skilled in agriculture and dyke-building. =Toucouleurs.= Sudanese Negroes of Senegambia, probably crossed with Hamitic blood; formerly dominant in the Western Sudan. =Tshi Group.= A group of Sudanese Negro tribes of the Guinea Coast, including the warlike Ashantis, Fantis and Adansis. =Tuaregs.= The predatory Berber (_q.v._) Nomads of the Sahara. =Tudas.= See DRAVIDIANS. =Tumalis.= See NUBA GROUP. =Tunguses.= A branch of the Mongol stock of the Northern Mongolic family, who lead a nomad existence in the mountains of East Siberia and the Amur region. They are of Mongolic physical type, with square skulls, low stature, and wiry, well-knit figures. They are distinguished by fine moral qualities, a fearless race of hunters, industrious, trustworthy, and self-reliant. Their main tribes are the Lamuts, or “sea people,” Orochs, Chapogirs, Golds, and Tazis. The modern Tunguses probably represent the primitive stock of the Manchus (_q.v._). =Tupi-Guarani.= A wide-spread family of South American Indians, in Brazil, including numerous distinct tribes, of which the Chiriguanas of Bolivia, Caribunas of the Rio Negro, Paraguay Indians, Tupinambas of the Para coast, Mundrucus of the Tapajos, Omaguas, Goajiris and Tocantins, are the most important. They are copper-coloured, thick-set and muscular, with broad features, black hair and sometimes obliquely set eyes. They are of apathetic nature, and are slow to acquire civilisation. =Tupinambas.= See TUPI-GUARANI. =Turanian.= An ethnological term, now abandoned, roughly corresponding to the Northern Mongolic or Ural-Altaic family. =Turguts.= See KALMUKS. =Turkanas.= An African Hamitic race, allied to the Masais (_q.v._), and dwelling between Lake Rudolf and the Nile. =Turki=, or =Turks=. An important and wide-spread stock of the Northern Mongolic family, dwelling in Central Asia, Asia Minor, and in European Turkey. The primitive Turki stock--the Chinese Tu-kiu and ancient Turcæ--seem to have inhabited the Altai region as early as the second century B.C. Thence they spread far and wide, and founded many powerful and predatory, but unstable empires. The Huns (_q.v._) who followed Attila were largely of Turki stock. Their chief modern race is that of the Ottoman Turks [see TURKS], who raised their empire on the ruins of Constantinople in 1453. Other Turki races are the Yakuts, Usbegs, Naimans Andijanis, Nogais, Tartars, Bashkirs, Kizil-Bashis, Anatolian Turks, etc. They are closely allied to the Kirghiz, Kipchaks, Kara-Kalpaks and Turkomans (_q.v._). The Turki physical type, of Mongol origin, has been modified by intermixture with Caucasic races. =Turks=, =Osmanlis=, or =Ottoman Turks=. The dominant inhabitants of the Turkish Empire in Europe and Asia Minor, the most powerful of Turki races. They trace their descent from the Seljuks, a confederacy of Turki tribes who were settled on the Jaxartes in the eleventh century, and there adopted Islam. They conquered Persia and established kingdoms in Syria--the great Saladin was one of their princes--and Asia Minor, or Anatolia. The true Ottoman Turks entered the service of the Seljuk rulers in the thirteenth century, being driven from Kharasan by the advance of the Mongol hordes, and under Othman and his successors they became the dominant Turk race. They reared a great military power, and soon invaded Europe, where they destroyed the Eastern Empire in the middle of the fifteenth century and founded the still existing Turkish Empire. The Ottoman Turks are proud, ignorant and fanatical, but honourable and upright. They make admirable soldiers, when properly led, but are surpassed in the arts of peace by their subject races, Greeks, Bulgarians, Jews, etc. =Turkomans.= A race of Turki nomads who inhabit the steppes east of the Caspian and south of the Oxus. They include such tribes as the Chaudors, Tekkes (Akhal and Merv), Salors, Yomuds, Goklen, and Ali-Elis. They were formerly noted for their predatory and man-stealing habits, but under Russian rule have been forced to live a more peaceful life. _m_ =Tusayas.= See PUEBLO INDIANS. =Tuscaroras.= North American Indians. See IROQUOIAN. =Tushis.= See CHECHENZES. =Tushilange.= A branch of the Baluba (_q.v._). =Tutelos.= See SIOUAN. =Tyrolese.= Natives of the Tyrol, the ancient Rhaetia, a mountainous district now belonging to the Austrian Empire. They are of High German Teutonic stock, and are noted for their patriotism and bravery, illustrated by their resistance under Hofer to the arms of Napoleon. They are industrious and thrifty, but backward in education, and devout Catholics. =Tyrrhenes.= An ancient pre-Hellenic race of Greece, found in Thrace and Etruria, who probably belonged to the Pelasgian stock of the Hamitic family, giving birth to the Etruscans (_q.v._). =Ugrian.= A branch of the Finno-Ugrian stock (_q.v._) including the Samoyedes, Voguls, Ostyaks, Soyots and Siryanians of Siberia, the Permian Finns of Russia, and the Magyars of Hungary. See under these heads. =Umbquas.= See ATHABASCAN. =Umbrians.= An ancient Italic race, perhaps allied to the Etruscans (_q.v._) or the Samnites, afterwards subjugated by Rome. =Ural-Altaic.= A term applied to the Northern Mongolic family of races, corresponding nearly to the older Turanian. It includes the Mongol, Turki, Finno-Ugrian, Siberian, and Koreo-Japanese stocks. =Uruts.= See SHARRAS. =Utahs.= See SHOSHONEAN. =Uzbegs.= Nomadic Turki race of the Oxus Basin. =Vaalpens.= A Negrito race of the Kalahari Desert, probably a half-breed between Bechuanas and Bushmen, formerly the serfs of the dominant Bantu races, but now freed under British rule. =Vandals.= A Teutonic race, settled at the dawn of the Christian era in North-east Germany between the Oder and the Vistula. Like the Goths, whom they physically resembled, they were a warlike and roving race. Early in the fifth century they invaded Gaul and formed a settlement in Spain, where Andalusia (anciently Vandalitia) preserves their name. Later, under the fierce Genseric, they crossed to Africa and over-ran Mauretania, where they established a short-lived piratical Empire. In 534 it was destroyed by a Byzantine army under Belisarius, and the Vandals thereafter disappeared as a separate race. Their name has become a by word on account of their turn for devastation. =Vaudois.= See WALDENSES. =Veddahs.= A primitive hunting people of Ceylon, who are sometimes classed as Dravidian, but more probably represent the still older (Negrito?) aborigines of the island. They are dwarfish, of dark complexion, with features intermediate between the Hindu and Papuan types. They rank among the rudest and least civilised of races, being equally unable to laugh, count, or cook. They are dying out. =Veis=, or =Vey=. A Sudanese Negro race, of Mandingan stock, on the West Coast of Africa, who are said to be the only Negro race who have invented an alphabet. =Venezuelans.= White natives of Venezuela, of Spanish descent. Most of them are crossed with Indian blood. =Vikings.= See NORSEMEN. =Visigoths.= See GOTHS. =Voguls.= A nomadic Finno-Ugrian race who inhabit both slopes of the Urals. They closely resemble the Ostyaks and Samoyedes (_q.v._). _m_ =Vuaregga=, =Vuarua=, =Vuarunga=, =Vuavinza=. Bantu Negro tribes inhabiting the Congo basin and the Tanganyika district. =Wachaga.= A predatory Bantu race on the southern slopes of Kilimanjaro. =Wadai Group.= A group of Sudanese Negro tribes inhabiting Wadai and East Darfur, including Birkits, Massalits, Korungas, Mabas (mixed with Hamitic blood), and other tribes. They are mainly of pastoral habit. =Waganda.= A Bantu Negro race who founded the kingdom of Uganda and attained a remarkable degree of civilisation before the arrival of white men. They are very intelligent, and their skill in the industrial arts has caused them to be called the Japanese of Africa. They are also warlike, and formerly indulged in frequent plundering and slave hunting raids among the surrounding races. =Wagogo.= A Bantu Negro race of German East Africa. =Wahehe.= See WASAGARA. =Wa-Huma.= A conquering pastoral race, of Eastern Hamitic stock, who migrated from Gallaland and penetrated as far south as Unyamwezi, founding various kingdoms on the way. They are of Hamitic features, fair complexion, and tall stature; very warlike. The ruling classes of Uganda and Unyoro are of Wa-Huma origin. The Wa-Huma are a branch of the Gallas (_q.v._). Among their tribes are the Wajiji, Warundi, Waruanda, etc. =Wajiji.= See WA-HUMA. =Waldenses=, or =Vaudois=. A heretical sect which originated in the South of France in the twelfth century, and was formed into a separate race by persecution; of French, Swiss, and Italian elements. They are now settled in Savoy. =Walloons.= Natives of South-eastern Belgium, of mixed Celtic and Romanic stock, probably descended from the ancient Belgae (_q.v._). They are tall, bony, and of strong physique, and are very successful in industry, as shown in the great manufacturing town of Liege. =Wanyamwezi.= A warlike Bantu race of German East Africa, who formerly composed a powerful predatory state. =Wanyoro.= Natives of Unyoro, in British East Africa, of Bantu race, skilled in industrial arts, and formerly allied with Arab slave-traders. =Wapisianas.= See ARAWAKS. =Wapokomo.= The chief Bantu race of the Tana basin, skilled boatmen and hunters, formerly under Masai domination, now acquiring civilisation under British rule. =Warraus.= An aboriginal Indian race of British Guiana. =Warua.= A powerful, warlike, and barbarous Bantu race of the Lualaba district in the Congo Free State, forming a powerful native state, and skilled in industry and rude art. =Waruanda=, =Warundi=. See WA-HUMA. =Wasagara.= A warlike and widespread Bantu people of German East Africa; fierce mountaineers, much given to marauding. The Wahehe, who claim Zulu affinities, are one of their tribes. =Waswahili.= See SWAHILIS. =Wataveita.= A mild and settled agricultural Bantu race inhabiting the slopes of Kilimanjaro in German East Africa. =Welle Group.= A group of Sudanese Negro races inhabiting the region of the Upper Welle River in Central Africa, including the cannibal Niam-Niam, or Azandeh, the Mangbattu, Nsakkara, Amadi, Ababua, and other tribes. =Welsh=, or =Cymry=. The chief surviving branch of the Brythonic or P Celts, inhabiting Wales, where they preserve their ancient language and customs. They probably represent the ancient Britons who inhabited England at the time of the Anglo-Saxon immigrations. “An old and haughty nation, proud in arms.” =Wends.= A stock of the Western Slavonic family, settled in the north and east of Germany in the sixth century. They were gradually absorbed by the Teutonic Germans. A remnant of the Wendish race, preserving their ancient language and customs, survives in Lusatia, on the borders of Saxony and Prussia, where they are also known as Sorbs. =Winnebagos.= See SIOUAN. =Wochuas.= See PYGMIES. =Wolofs.= Sudanese Negroes, dwelling between Lower Senegal and Gambia; very black, but with regular features, indicating a trace of Hamitic blood. Their chief branch is that of the Jolofs. =Wulwas.= See LENCAN. =Xanthochroi.= A suggested division of Caucasic Man, opposed to the Melanochroi, characterised by fair hair, blue eyes, and rosy complexion. It would thus include the Teutonic, Scandinavian, and Slavonic stocks of the Aryan family. =Xosas=, or =Amaxosa=. The southern stock of the Kafir race (_q.v._), allied to the Zulus, or northern stock. They are eminently warlike, and have an interesting system of social organisation. They are of Bantu origin, immigrants from the north, who have dispossessed the Hottentot or Bushman aborigines. They are tall, well-built, and muscular, with Negro features and complexion, and woolly hair. They are semi-nomadic cattle-breeders and hunters, but many have taken to the settled pursuits of agriculture. They were long at war with the British and Boer settlers, but are now a peaceful and contented people under British rule. =Yakuts.= A Mongolic race of Turki stock, inhabiting the province of Yakutsk in East Siberia. They are of middle height, with black hair, flat noses, and narrow eyes. They are laborious and enterprising, and show more aptitude for civilisation than the Buriats or Tunguses. They inhabit log “yurtas” in winter, but camp out in summer. Cattle-breeding, and to a less degree agriculture, are their chief occupations. =Yankees.= Natives of the New England States. In a wider sense, the northern inhabitants of the United States. =Yaos.= Agricultural aborigines of French Indo-China, perhaps allied to the Chinese proper. =Yedinas.= See LAKE CHAD GROUP. =Yomuds.= See TURKOMANS. =Yorubas.= A group of Sudanese Negro races inhabiting the eastern half of the Slave Coast district, and united by a common Yoruba language, though much broken up by political feuds. They are peacefully disposed, industrious, and friendly to strangers. Their main pursuit is agriculture, but they also practise many industries; they are the best architects in Africa. Their chief tribes are those of Egba, Jebu, Oworo, Ondo, Ife, and Oyo. Abeokuta, the Egba capital, owes its fame to the success with which it held out as a city of refuge against the slave-hunters of Dahomey and Ibadan. =Yukaghirs.= A nomadic tribe of north-east Siberia, probably identical with the Tunguses (_q.v._). =Yumas.= See OPATA-PIMA. =Yuruks.= A nomadic Turki race in the Konia vilayet of Turkey-in-Asia. =Yusufzais.= See AFGHANS. =Zambos.= See SAMBOS. =Zaparos.= South American Indians, on the Upper Napo in Peru. =Zapotecs.= Central American Indians of Oajaca in Mexico. =Zendals=, =Zotzils=. See MAYA-QUICHÉ. =Zulus=, or =Amazulu=. A very warlike Bantu race, allied to the Xosas and other Kafir tribes, whom they resemble in physique and organisation. Originally a small Kafir clan, the Zulus were raised to eminence at the beginning of the nineteenth century by the genius of Tchaka, a kind of Negro Napoleon, who established a severe military despotism, and dominated South Africa from the Zambesi to Cape Colony by the courage and military skill of his regiments. Tchaka’s descendants ruled Zululand proper, and waged war against Kafirs, Boers, and English, until their country was annexed by Britain in 1887. The Zulus are both physically and mentally one of the finest of African races. =Zunis.= See PUEBLO INDIANS. [Illustration: TYPES OF THE CHIEF LIVING RACES OF MANKIND 1. Anglo-Saxon 2. Finn 3. Celtic 4. Bulgarian 5. Greek 6. Caucasian 7. Tartar 8. Arab 9. Fellah 10. Berber 11. Syrian 12. Afghan 13. Javanese 14. Malay 15. Ladrone Islander 16. Hindu 17. Samang 18. Negrito ] 19. Chinese 20. Japanese 21. Tartar 22. Aleutian 23. Kalmuck 24. Kamchadale 25. Aleoutian 26. Esquimau 27. Ainu 28. Samoyede 29. Koriak 30. Stone Indian 31. Otoe Indian 32. Kutchin Indian 34. Yucatan Indian 33. Chili Indian 35. Fuegian ] [Illustration: GROUPED ACCORDING TO PHYSIOLOGICAL RELATIONSHIP 36. Jeba Negro 37. Beja 38. Sahara Negro 39. Hottentot 40. Kafir 41. Mozambique Negro 42. North Australian 44. South Australian 43. West Australian 45. Tasmanian 46. Tikopia Islander 47. Maori 48. Samoan 49. Melanesian (Vanikoro Island) 50. Melanesian (New Hebrides) 51. Fijian ] ETHNOLOGICAL CHART OF THE HUMAN RACE This Chart, intended for reference in connection with the Dictionary of Races beginning on page 311, gives a view of the various main divisions, families, and stocks into which the human race is divided by ethnologists. It is impossible to give a complete list of the individual races within the necessary limits, but the chief typical races are named under each stock in the right-hand column. The races marked with an asterisk are extinct. ETHIOPIC DIVISION Family Stock Typical races AFRICAN NEGRO _Sudanese_ {Mandingan {Ashanti {Hausa {Azandeh _Bantu_ {Herero {Wanyamwezi {Basuto {Waganda {Ama-Xosa (Kafir) {Zulu _Hottentot-Bushman_ {Nama {Griqua {Bushman AFRICAN NEGRITO _Pygmy_ {Wochua {Akka {Obongo OCEANIC-NEGRO _Papuan_ {New Guinea natives _Melanesian_ {Fijian {Solomon Islanders _Australian_ {Australian aborigines {Tasmanian* OCEANIC NEGRITO _Negrito_ {Andamanese {Sakai {Aeta MONGOLIC DIVISION Family Stock Typical races NORTHERN MONGOLIC {Sharra {Kalmuk _Mongol_ {Buriat {Tungus {Turks {Tartars _Turki_ {Bashkirs {Kirghiz {Turkoman {Samoyede {Magyar _Finno-Ugrian_ {Finn {Bulgar {Lapp _Siberian_ {Chukchi {Kamchadale _Koreo-Japanese_ {Korean {Japanese _Dravidian(?)_ Tamil SOUTHERN MONGOLIC {Tibetan _Tibetan_ {Balti {Lushai {Burmese _Indo-Chinese_ {Siamese {Bhil {Annamese {Chinese _Chinese_ {Punti {Lolo OCEANIC MONGOLIC {Malay _Malaysian_ {Dyak {Javanese _Malagasy_ Hova _Philippine_ {Visayan {Ilocano _Formosan_ AMERICAN DIVISION Family Stock Typical races ARCTIC _Eskimo_ {Eskimo {Aleutian NORTH AMERICAN INDIAN _Athabascan_ {Apache {Navajo _Algonquian_ {Delaware {Mohican {Blackfoot _Iroquioan_ {Huron {Mohawk {Cherokee _Thlinkit_ Thlinkit _Haida_ Haida _Chinook_ Chinook _Siouan_ {Sioux {Dakota {Omaha _Shoshonean_ {Shoshone {Utah {Comanche {Pawnee _Muskhogean_ {Choktaw {Seminole _Natchez_ Natchez* _Kiowa_ Kiowa _Salish_ Flathead _Pueblo_ {Zuni {Taos CENTRAL AMERICAN INDIAN _Otomi_ Otomi _Opata-Pima_ {Cora {Tarahumara _Guaicuri_ Guaicuri _Tarascan_ Tarascan _Nahuan_ {Toltec {Aztec {Mexican _Maya-Quiché_ {Maya {Quiché {Huastec _Lencan_ {Chontal {Guatusa _Bribri_ Bribri _Talamanca_ Talamanca _Zapotec_ Zapotec _Miztec_ Miztec _Chorotegan_ Chorotegan SOUTH AMERICAN INDIAN _Inca_ {Quichua {Chanca _Aymara_ Aymara _Chibcha_ Chibcha _Choco_ Choco _Zaparo_ Zaparo _Jivaro_ Jivaro _Mojo_ Mojo _Chiquito_ Chiquito _Barré_ Barré _Charrua_ Charrua* _Chuncho_ Chuncho _Conibo_ Conibo _Carib_ {Macusi {Rucuyenne _Arawak_ {Maypuri {Wapisiana _Warrau_ Warrau _Botocudo_ Botocudo _Tupi-Guarani_ {Paraguay {Caribuna {Tupinamba _Payagua_ Payagua _Matacoan_ Matacoan _Toba_ Toba _Araucanian_ Araucanian _Puelche_ {Puelche {Gaucho _Patagonian_ Patagonian _Fuegian_ Fuegian CAUCASIC DIVISION Family Stock Typical races HAMITIC _Eastern_ { Egyptian { Somali { Galla { Masai _Western_ { Numidian Berber { Iberian { Basque { Pict* { Ligurian Corsican { Pelasgian { Mycenæan* { Etruscan* SEMITIC _Assyrian_ Chaldæan* _Aramæan_ { Syrian { Hittite* _Canaanite_ { Israelite { Phœnician* { Carthaginian* _Arab_ { Arab { Bedouin _Himyarite_ Abyssinian ARYAN _Hindu_ { Punjabi { Bengali _Iranian_ { Afghan { Persian { Armenian { Kurd _Hellenic_ { Albanian { Greek _Italic_ { Roman { Italian { French { Spanish { Portuguese { Latin American _Keltic_ { Goidelic { Irish { or { Manx { Q Kelts { Highland Scottish { Brythonic { Welsh { or { Breton { P Kelts { Cornish* _Lettic_ { Lithuanian { Lettish _Slavonic_ { Russian { Czech { Polish { Servian _Scandinavian_ { Norwegian { Swedish { Danish _Teutonic_ { Low { Old Saxon* { German { Dutch { { Flemish { { Anglo-Saxon { High { German { German { Saxon { Swiss { Austrian CAUCASIAN _Southern_ Georgian _Western_ Circassian _Eastern_ { Chechenz { Lesghian INDONESIAN _Polynesian_ { Samoan { Maori { Marquesan AINU _Ainu_ Ainu [Illustration: MAKING OF THE NATIONS AND THE INFLUENCE OF NATURE] THE BIRTH & GROWTH OF NATIONS BY PROFESSOR RATZEL In order that the cosmic conception of the life of man may be more than a mere isolated idea, incapable of being applied and developed, it is necessary to indicate the relation which human life bears to the collective life of the earth. [Sidenote: Man is Bound up with the Earth] Human existence is based upon the entire development of vegetable and animal life; or, as Alexander von Humboldt said, in reality the human race partakes of the entire life on earth. Just as plants and animals, vegetable and animal remains and products, occupy an intermediate position between man and the inanimate substance of the earth, so almost without exception the life of man depends not directly upon the earth, but upon the animals and plants, which in turn are immediately bound to the earth by the necessities of existence. It is the dependence of later and more evolved types upon the earlier and less evolved. In 1845 Robert Mayer, the German scientist, published his epoch-making thesis on “The Relations of Organic Motion to Metabolism,” in which he described the vegetable world as a reservoir wherein the rays of the sun are transformed into life-supporting material and are stored up for use. According to his view the physical existence of the human race is inseparably linked together with this “economic providence”; and he even went so far as to connect it with the instinctive pleasure felt by every eye at the sight of luxuriant vegetation. [Sidenote: Man’s Fight with Plants and Animals] [Sidenote: Spreading Life Over all the Earth] The history of mankind shows how various are the elements contained in this reservoir, and how manifold their action. Originally plants and animals share the soil with man, who must struggle with them for its possession. The plains favour and the forests obstruct historical movement; the inhabitant of the tropics is hardly able to overcome the growth of weeds that covers his field; for the Esquimau the vegetable world exists but two months in the year, and then only in stunted, feeble species. The unequal distribution of edible plants has in a large measure been the cause of divergence in the developments of different races. Australia and the Arctic countries have received almost nothing; the Old World has had abundance of the richest gifts showered upon it, Asia receiving more than Africa or Europe. The most valuable of domestic animals are of Asiatic origin. America’s pre-European history is incomparably more uniform than that of the Old World, and this is owing to her moderate endowment of useful plants and almost complete lack of domestic animals. The transplanting of vegetable species from one part of the earth to another, carried on by man, is one of the greatest movements in the collective life of the world. Its possibilities of extension cannot be conjectured; for the successful diffusion of single cultivated plants--the banana, for example--over a number of widely separated countries is yet problematical. This process can never be considered to have come to an end so long as necessity forces man to get a firmer and firmer hold on the store of earthly life. The relations of man to the earth are primarily the same as those of any other form of life. The universal laws of the diffusion of life include also the laws of the diffusion of the human species. Hence the study of the geographical distribution of man must be looked upon only as a branch of the study of the geographical distribution of life, and a succession of the conceptions belonging to the latter. [Sidenote: The Material Tie that Binds Men Together] To these conceptions belong the main area of distribution, the habitable world, and all its various parts: zones, continents, and other divisions of the earth’s surface, especially seas, coasts, interiors of lands, bordering regions, divisions exhibiting continuity with others as links in a chain, and isolated divisions. Also relations as to area: the struggle for territory, variations in the life development in small or inextensive regions, in insular or in continental districts, on heights of land and plateaus, and, in addition, the hindrances and the aids to development presented by different conformations; the advance development in small, densely populated districts; or the protection afforded by isolated situations. All must be included. Finally, properties of boundaries must be conceived of as analogous to phenomena occurring on the peripheries of living bodies. As races are forms of organic life, it follows that the state cannot be comprehended otherwise than as an organised being; every people, every state is organic, as a combination of organic units. Moreover there is something organic in the internal coherence of the groups and individuals from which a state is formed. However, in the case of a people and a state, this coherence is neither material nor structural; states are spiritual and moral organisms. But, together with the spiritual, there is also a material coherence between the individual members of a race or a nation. This is the connection with the ground. The ground furnishes the only material tie that binds individuals together into a state; and it is primarily for this reason that all history exhibits a strong and ever-increasing tendency to associate the state with the soil--to root it to the ground, as it were. [Sidenote: The State and the Soil] The earth is not only the connecting principle, but it is also the single tangible and indestructible proof of the unity of the state. This connection does not decrease during the course of history, as might be supposed, owing to the progressive development of spiritual forces; on the contrary, it ever becomes closer, advancing from the loose association of a few individuals with a proportionately wide area in the primitive community, to the close connection of the dense population of a powerful state with its relatively small area, as in the case of a modern civilised nation. In spite of all disturbances, the economic and political end has ever been to associate a greater and greater number of individuals with the soil. Hence the law that every relation of a race or tribe to the ground strives to take a political form, and that every political structure seeks connection with the ground. The notion of an unterritorial and a territorial epoch in the history of man is incorrect; ground is necessary to every form of state, and also to the germs of states, such as a few negroes’ huts or a ranch in the Far West. Development consists only in a constant increase in the occupation and use of land, and in the fact that, as populations grow, so do they become ever more firmly rooted in their own soils. [Sidenote: If One State Embraced the Whole Earth] At the same time the nature of the movements of peoples must change. Penetration and assimilation of one race by another occur instead of displacement of one by another; and with the rapid decrease of unoccupied territory the fate of the late-comers in history is irrevocably sealed. Since the state is an organism composed of independent individuals and households, its decay cannot be analogous to the death and corruption of a plant or an animal. When plants decay, the cells of which they are composed decay also. But in a decayed state the freed individuals live on and unite together into new political organisms; they increase, and the old necessity for growth continues in the midst of the ruin. The decay of nations is not destruction; it is a remodelling, a transformation. A great political institution dies out; smaller institutions arise in its place. Decay is a life necessity. Nothing could be more incorrect than the idea that the growth of nations would come to an end were one state to embrace the whole earth. If this were to happen, long before the great moment of union came, there would be a multitude of processes of growth already in operation, ready to rebuild in case of decadence, and to provide for a new organisation if needed. As yet the political expansion of the white races over the earth has not resulted in uniformity, but in manifoldness. [Illustration: THE PEOPLE OF THE MOUNTAINS: SHOWING THE INFLUENCE OF ENVIRONMENT ON CHARACTER This picture, by Alexander Johnston, illustrates the keynote of Professor Ratzel’s chapters on the influence of the earth on character. Johnston represents a marriage among the Scottish Covenanters, who, persecuted under the Stuarts, took to the moss-hags and the hills, of whose stern ruggedness their own stern independence was the outcome and counterpart. ] [Sidenote: Earth and the Movements of Peoples] All conditions and relations of peoples and states that may be geographically described, delineated, surveyed, and, for the greater part, even measured, can be traced back to movements--movements that are peculiar to all forms of life, and of which the origin is growth and development. However various these movements may be in other respects, they are always connected with the soil, and thus must be dependent upon the extent, situation, and conformation of the ground upon which they take place. Therefore, in every organic movement we may perceive the activity of the internal motive forces which are peculiar to life, and the influences of the ground to which the life is attached. In the movements of peoples, the internal forces are the organic powers of motion common to all creatures, and the spiritual impulses of the intellect and will of man. In many a view of history these forces alone appear; but it must not be forgotten that they are conditioned by the fact that they cannot be active beyond the general limits of life, and they cannot disengage themselves from the soil to which life is bound. In order to understand historical movements it is first necessary to consider their purely mechanical side, which is shown clearly enough by an inquiry into the nature of the earth’s surface. Neglect of this occasions a delay in the understanding of the true character of such movements. Men merely spoke of geography, and treated history as if it were an atmospheric phenomenon. [Sidenote: National Emigrations in History] Nations are movable bodies whose units are held together by a common origin, language, customs, locality, and often necessity for defence--the strongest tie of all. A people expands in one direction and contracts in another; in case of two adjacent nations, a movement in the one betokens a movement in the other. Active movements are responded to by passive, and vice versa. Every movement in an area filled with life consists in a displacement of individuals. There are also currents and counter-currents: when slavery was abolished in the Southern States of America, an emigration of white men from the South was followed by an influx of ex-slaves from the North, thus causing an increase in the black majority of the South. [Sidenote: Why Nations Must Seek New Homes] Such external movements of peoples assume most varied forms. History takes a too narrow view in considering only the migrations of nations, looking upon them as great and rare events, historical storms as it were, exceptional in the monotonous quiet of the life of man. This conception of historical movements is very similar to the discarded cataclysmic theory in geology. In the history of nations, as in the history of the earth, a great effect does not always involve a presupposition of its being the immediate result of a mighty cause. The constant action of small forces that finally results in a large aggregate of effect must be taken into account in history as well as in geology. Every external movement is preceded by internal disturbance: a nation must grow from within in order to spread abroad. The increase of Arabs in Oman led to an emigration to East Africa along highways of traffic known to times of old. Merchants, craftsmen, adventurers, and slaves left their native land and drew together in Zanzibar, Pemba, and on the mainland. The process was repeated from the coast to the interior, and as a result of the aggregate labour of individuals as merchants, colonists, and missionaries, Arabian states grew up in the central regions of Africa. Instances of the occupation of vacant territories are of the greatest rarity in history as we are acquainted with it. The best example known to us is the settlement of Iceland by the Northmen. The rule is, a forcing in of the immigrating nation between other races already in possession; the opposition of the latter often compels the former to divide up into small groups, which then insinuate themselves peacefully among the people already established in the land. [Illustration: THE NORTHMEN TAKING POSSESSION OF ICELAND Instances of peoples taking possession of uninhabited lands and settling therein are extremely rare. Iceland is the best example known. The hardy Northmen took possession of it in the ninth century, but found the country untenanted. ] [Sidenote: The Human Will Knows no Obstacle] The movements of nations resemble those of fluids upon the earth: they proceed from higher altitudes to lower; and obstacles cause a change of course, a backward flow, or a division. Though at first there may be a series of streams running along side by side, there is a convergence at the goal, as shown by the migration of different peoples to a common territory; there is concentration when there are hindrances to be overcome, and a spreading out where the ground is level and secure. One race draws other races along with it; and, as a rule, a troop of wanderers come from a long distance will be found to have absorbed foreign elements on its way. But it would be wrong to look upon the movements of nations as passive onflowings, or even to deduce a natural law from the descent of tribes from the mountains to the river valleys and to the sea--an idea that once led to the acceptance of the theory of the Ethiopian origin of Egyptian civilisation. Either the wills of individuals unite to form a collective will, or the will of a single man imposes itself upon the aggregate. The human will knows no insurmountable obstacle within the bounds of the habitable earth. [Sidenote: Bursting Nature’s Barriers] As time goes on, all rivers and all seas are navigated, all mountains climbed, and all deserts traversed. But these have all acted as obstructions before which movements have either halted or turned aside, until finally they have burst the barriers. At least two thousand years passed from the time of the first journey of a Phœnician ship out through the Pillars of Hercules into the Atlantic until the arrival of the day when a voyage across was ventured from Southern Europe. The Romans turned at the Alps, both to the right and to the left, seven hundred years after their city had been founded, but how many nooks in the interior of those mountains were unknown to them even centuries later! Yet to-day Europe feels the effect of this circumstance, the fact that the Romans did not advance straight through the Central Alps into the heart of the Teutonic country. They followed a roundabout way through Gaul, and thus Mediterranean culture and Christianity were brought to Central Europe from the west instead of from the south; hence the dependence of the civilisation of Germany upon that of France. It is precisely the Romans who, contrasted with barbarians, show us that will or design in the movements of nations does not necessarily increase with growth of culture, even though culture constantly puts more means of action at its disposal, improved methods of transportation, by which the way may be lightened. The mounted bands of Celts and Germans crossed the Alps quite as easily as did the Roman legions; and in spreading about and penetrating to every corner of the Alps and the Pyrenees, the barbarians were always superior to the Romans. [Sidenote: The Great Wanderers of the Earth] Wandering tribes of semi-civilised people are smaller, less pretentious, and less encumbered. In every war that has taken place in a mountain land, the greater mobility of untrained militia has often led to victories over regular troops. Races of inferior culture are invariably more mobile than those of a higher grade of civilisation; and they are able to equalise the advantages of the superior modes of locomotion with which culture has supplied the latter. Mobility also indicates a weaker hold upon the ground, and thus uncivilised peoples are more easily dislodged from their territories than are nations capable of becoming, as it were, more deeply rooted. In nomadic races, mobility bound up with the necessity for an extensive territory assumes a definite form, and, owing to a constant preparedness for wandering and to the possession of an organised marching system, such peoples have been among the greatest forces in Old World history. Movements of nations are often spoken of as if certain definite directions were forced upon them by some mysterious power. This view not only wraps itself in the garment of prophecy--for example, when announcing that the direction in which the sun travels must also be that of history--but it formally presupposes a necessary east-to-west progression of historical movements, endeavouring to substantiate its doctrine by citation of examples, from Julius Cæsar to the gold-seekers of California. But this necessity remains always in obscurity. Not only is it contradicted by frequently confirmed reflex movements in historical times, but it is also disproved still more by the great migrations which have taken place on the same continent in contrary directions. In Asia the Chinese have spread over the entire area of interior plain and desert, westward to the nation-dividing barriers of the Pamir Mountains; other Asiatic races have overflowed into Europe--also from east to west. Contrariwise, ever since the sixteenth century we have seen the Russians at work conquering the entire northern part of the continent, constantly pressing on towards the east. Even the sea proved no obstacle, for they both discovered and acquired Alaska during the course of this same movement. [Illustration: HOW CIVILISATION SPREAD THROUGH EUROPE The inexorable influence of physical conditions on the life of the peoples is well illustrated by the influence of the Alps in deflecting the path of Mediterranean culture. These mountains hemmed in the north of the Roman Empire and forced the Romans, in their expansion, to the west. Hence Mediterranean culture and Christianity were carried to Central Europe from the west instead of from the south, and the civilisation of Germany depends on that of France. The map shows the route followed by the stream of Roman civilisation. ] We shall not attach any universal significance to such fashionable terms employed in historical works as political or historical attraction, elective affinity or balance; least of all shall we presume to discover occult, mysterious sources for them. It is obvious that a powerful nation will overflow in the direction of least resistance; and in the case of a strong Power confronting one that is weak there is a constant movement toward the latter. Thus, from the earliest times, Egypt has pressed on toward the south; and everywhere in the Sudan we find traces of similar movements to the south as far as Adamawa, where they are still to-day in energetic continuance. The history of colonisation in America shows a turning of the streams of immigration, in the south as well as in the north, towards the more thinly settled regions; the more thickly populated are avoided. The migrations of nations, which took place during periods of history when a surplus of unoccupied land existed, were determined to a great extent by natural causes. The more numerous nations become, the greater the obstacles to migration, for most of these obstacles arise from the very nations themselves. Nations increase with their populations; lands with enlargement of territory. So long as a country has sufficient area, the second form of growth need not of necessity follow the first--the race spreads out over the gaps which are open in the interior, and thus internal colonisation takes place. If there is need for emigration, occupiable districts may be found in the lands of another people--for centuries Germans have thus found accommodation in Austria, Hungary, Poland, and America. [Sidenote: How New States are Born] Of course, such colonists gradually become absorbed into the people among whom they have settled. This is simple emigration, which is therefore connected with the internal colonisation of a foreign land. External colonisation first comes into being when a state acquires territory under its control, into which territory, if it be suitable, a portion of the inhabitants of the state move and settle. Colonisation is not necessarily a State affair from the first. If a race inhabit a country so sparsely as the Indians did America in the sixteenth century, a foreign people, having the power of spreading out, may press into the gaps with such success that this initial internal colonisation may also be advantageous from a political standpoint. The State then intervenes and appropriates the territory over which groups of its inhabitants have previously acquired economic control. The emigrants formed a social aggregate in the new country, and from this aggregate a state, or the germ of a state, develops. Since such an economic-social preparatory growth greatly assists in the political acquirement of land, it is obvious that this form of colonisation is especially sound and effectual. The opposite method follows when a state first conquers a territory which it occupies later with its own forces; this is colonisation by conquest. It can be capable of development only when subsequent immigration permanently acquires the land as a dwelling-place. [Sidenote: Why Rome’s Empire Endured Long] Conquest that neither can nor will take permanent possession of the soil is characteristic of a low stage of culture; thus the Zulu states in Africa, surrounded by broad strips of conquered yet uncontrolled territory, and the old “world-empires” of Western Asia, exhausted themselves in vain efforts to obtain lasting increase of area through aggressive expeditions. That the Roman Empire lasted a longer time than any of the preceding universal empires was due to the single fact that agricultural colonisation invariably followed in the footsteps of its political conquests. The enlargement of a nation’s area is associated with soil and inhabitants. If the increase of territory--for example, through conquest--is much more rapid than the increase of population, an inorganic, loosely connected expansion results, which, as a rule, is soon lost again. If, on the contrary, population increases at a proportionately greater rate than area, a crowding together, checks to internal movements, and over-population follow. In consequence, great discrepancies between growth of territory and increase of population lead to the most varied results. The conquering nation expands over extensive regions for which there are no inhabitants. Passive races in India and in China become so crowded together that it is impossible for their soil to support them any longer; hence a continuous degradation and recurrent periods of famine, which may bring with them a relatively feeble and unorganised emigration. [Sidenote: The Modern Nations as Colonisers] There are nations with whom conquest and colonisation seem to follow in most profitable alternation: this appears to have been the case with all colonising countries of modern history that have followed the example of the Roman Empire. But there are great contrasts presented even by these nations. Germany, Austria, and Russia, in immediate connection with their conquered provinces, have colonised and expanded toward the east. In spite of a rapid increase of population, Germany has been backward in establishing trans-marine colonies, while France, with a proportionately smaller increase of population, began by colonising in all directions, but occupied more land than she was able to master; for which reason colonization in the history of France has taken more or less the character of conquest. England, on the contrary, with a vigorous emigration and an expansive movement in all directions, presents an example of the soundest and strongest method of founding colonies which has been seen since early times. ABBREVIATIONS BR. BRITISH FR. FRENCH SP. SPANISH RU. RUSSIAN GER. GERMAN DU. DUTCH PORT. PORTUGUESE G. F. MORRELL 1907. THE EXPANSION OF THE WHITE RACES THROUGHOUT THE WORLD This map illustrates the extent to which the white races have spread into other than their native lands. The pale tint, as on the British Isles, indicates the native land of the whites; the darker tint shows where whites have settled down; while the black portions represent those parts of the earth where the coloured races predominate. ] [Sidenote: Some New National Problems] Through the entire course of history an ever-increasing value attached to land may be traced; and in the expansion of nations we may also see that mere conquest is growing less and less frequent, while the economic acquisition of territory, piece by piece, is becoming the rule. The getting of land assumes more and more the character of a peaceful insinuation. The taking possession of distant countries without consideration for the original inhabitants, who are either driven away, or murdered--speedily with the aid of bullets, or slowly with the assistance of gin or contagious diseases or by being robbed of their best land--is to-day no longer possible. Colonisation has become a well-ordered administration combined with instruction of the natives in useful employments. The old method has left scarcely a single pure-blooded Indian east of the Mississippi in the United States, and not one native in Tasmania; the new method has before it the problem how to share the land with negroes--in the Transvaal with 74 per cent. and in Natal with 82 per cent. Climatic conditions are also to be taken into consideration, for Caucasians are able to develop all their powers in temperate regions only; a hot climate impels them to ensure the co-operation of black labour through coercion. [Sidenote: Mankind Ages with Civilisation] During the course of centuries a motley collection of countries has developed, all of which are called colonies, although they stand in most striking contrast with one another. Several are nations in embryo, to which only the outward form of independence is lacking; not a few have once been independent; and many give the impression that they will never be fit for self-government. There are some in which the native population has become entirely extinct, such as Tasmania, Cuba, and San Domingo; others in which the original inhabitants, still keeping to their old customs and institutions, are guided and exploited by a few white men only; and, finally, colonies in which the rulers and the natives have assimilated with one another, as in Siberia. Once upon a time such tokens of the youth of races as may be seen in rude but remunerative labour on unlimited territory were widespread in many colonies. But the new countries fill up visibly, and even they show that mankind, as a whole, ages the more rapidly the more the so-called progress of civilisation is hastened. However, an examination of the peoples of the present day shows that the differences in age between mother-countries and colonies will, indeed, continue for a long time yet. Such differences exist between west and east Germans as well as between New Englanders and Californians; they are even to be detected in Australia, between the inhabitants of Queensland and of New South Wales. Such differences are shown not only in the characteristics of individuals, but also in the division of land and in methods of labour. [Sidenote: Nations Hold fast to Nature] Divergence and differentiation are the great factors of organic growth. They govern the increase of nations and states from their very beginnings. Since, however, these organisms are composed of independent units, differentiation does not consist in an amalgamation and transformation of individuals, but in their diffusion and grouping. Therefore the differentiation of nations becomes eminently an affair of geography. Never yet has a daughter people left its mother-country to become an independent state without a previous disjunction having taken place. All growth is alteration in area, and, at the same time, change in position. The further growth extends away from the original situation, the sooner dismemberment follows. In Australia, New South Wales spreads out towards the north, and at the new central point, Brisbane, a new colony, Queensland, is formed, which already differs materially from New South Wales. And Queensland itself expands towards the north, beyond the tropic of Capricorn into the torrid zone; and a younger, tropical North Queensland develops. [Illustration: LANDMARKS OF PAST AGES: FAMOUS FORTRESSES THAT HAVE CEASED TO BE OF USE With the changing conditions of politics, places once of enormous importance have often become mere curiosities. There are in Europe to-day hundreds of useless castles, fortresses, and harbours. Even Dover Castle is of little strategic value. The fortresses illustrated are (1) Mantua, (2) Dover, (3) Chillon, (4) Calais, (5) Verona. Photographs by Frith and Neurdein ] [Sidenote: The Genius of the Coloniser] The fact that nations hold fast to their natural conditions of existence, even when growth impels them towards expansion in various directions, is a great controlling force in historical movement. Russia expands in its northern zone to the Pacific ocean; England continues its growth on American soil, across the Atlantic, in almost the same latitude. The Phœnicians, as a coast-dwelling people, remained on the coasts and on the islands; the colonising Greeks ever sought out similar situations to those of their native land; the Netherlanders are found everywhere in Northern Germany as colonists of the moors and marshes. All German colonies beyond the Alps and the Vosges have disappeared; and the few Germans that remain are Latinised. Nations that are accustomed to a limited territory, as were the Greeks, always search for a similar limited area; on the other hand, the Romans discovered a main factor of empire-building in their judicious agricultural colonisation of broad plains; and the Russians sought and found in Siberia the endless forests, steppes, and vast rivers of their native land. Every nation, in expanding, seeks to include within its area that which is of the greatest value to it. The victorious state acquires the best positions and drives the conquered race into the poorest districts. For this reason competition between the colonizing nations has become very keen; they all judge of the character of territory according to the same standard. Therefore, wherever England has colonised, only a gleaning remains for the rest of the Northern and Central European Powers. Differentiation, arising from the valuation of land, is the cause of a constant creation of new political values and of a constant lapsing of old. Every portion of the world has its political value, which, however, may become dormant, and must then be either discovered or awakened. Such a discovery was the selection of the Piræus as the harbour for Athens from among a number of bights and bays. [Sidenote: The World is Being Centralised] Every settlement and every founding of a city is at bottom an awakening of dormant political value. Capacity for recognizing this value is a part of the genius of a statesman, whose policy may be called far-seeing partly because he is able to discern the dormant value while yet on the most distant horizon. It is obvious that political values vary; each is determined by the point of view from which it is looked upon. The French and the German valuations of the Rhine borderland are very different. Every nation endeavours to realise the political value which it recognises; and in respect to political growth, ends are set up in the shape of the portions of the earth to which that growth aspires. Peculiarities in the conformation of states may be traced back to an appreciation of the value of coasts, passes, estuaries, and the like. With the spreading out and the concentration of nations, such portions of the world as are important from a political point of view have marvellously increased both in number and in value. But for this very reason a choice of selection has become necessary, and this we see in the use of fewer Alpine passes during the age of railways than before, and in the concentration of a great commerce into fewer seaports--into such as are capable of accommodating vessels of the deepest draught. Others must withdraw from competition. To-day there are hundreds of worthless harbours, passes, and fortresses in Europe that were once situated on the highways of historical movement; now however, they are avoided, deserted by the current of traffic. [Sidenote: All the Rubbish of Civilisation] There are more things necessary to an understanding of the dependence of history on natural conditions than a mere knowledge of the land upon which the development has taken place, particularly than a mere knowledge of the ground as it was when history found it. Although each country is in itself an independent whole, it is at the same time a link in a chain of actions. It is an organism in itself, and, in respect to a succession or a group of lands forming a whole, of which it is a member, it is also an organ. Sometimes it is more organism than organ; sometimes the opposite is true; and an eternal struggle goes on between organism and organ. If the latter be a subjected province, a tributary state, a daughter country, a colony, or member of a confederation, the striving for independence is always a struggle for existence. This by no means presupposes a state of war. Not only war, but the outwardly peaceful economic development of the world’s industries reduces organisms to organs. When the wholesale importation of bad but cheap products of European industries into Polynesia or Central Asia causes decay in the production of native arts and crafts, it is a loss to the life of the whole people; henceforth the race will be placed in the same category with tribes that must gather rubber, prepare palm-oil, or hunt elephants to supply European demand, and who in turn must purchase threadbare fabrics, spirits that contain sulphuric acid, worn-out muskets, and old clothes--in a word, all the rubbish of civilisation. Their economic organisation dies; and in many cases this is also the beginning of the decline and extinction of a people. The weaker organism has succumbed to the more powerful. Is the case so different--that of Athens, unable to live without the corn, wood, and hemp of the lands on the Northern Mediterranean coast?--or of England, whose inhabitants would starve were it not for the importation of meat and grain from North America, Eastern Europe, and Australia? In vain have men sought for characteristics in the rocks of the earth and in the composition of the air by which one land might be distinguished from another. Underwood and Underwood. MAN’S WONDERFUL TRIUMPH OVER NATURE By irrigation the arid desert of California has been made to blossom as the rose in the luxurious orange groves of Riverside. These views show the desert, the method of irrigation, and the result of man’s labour. ] [Sidenote: How Man is Levelling the Earth] The idea of great, lasting, conclusive qualitative variations in different parts of the earth is mythical. Neither the Garden of Eden nor the land of Eldorado belongs to reality. There is no country whose soil bestows wondrous strength upon man or an exuberance of fruitfulness upon woman. In India precious stones are as little apt to grow out of the cliffs as silver and gold are likely to exude from fissures in the earth. Nor is there any basis for the slighter differences between the Old World and the New which the philosophers of history of the eighteenth century believed they had discovered. The opinion that the New World produces smaller plants, less powerful animals, and finally a feebler humanity, was not unconditionally rejected by even Alexander von Humboldt. The degeneration and wasting away of the American Indians would certainly be a less disgraceful phenomenon could it be attributed to some great natural law instead of to the injustice, greed, and vices of the white men. In the course of development of the European daughter-nations in America we cannot recognise any such great and universal distinction. The course of history in America, just as in corresponding periods of time in Northern Asia, in Africa, and in Australia, only confirms the belief that lands, no matter how distant from one another they may be, whenever their climates are similar, are destined to be scenes of analogous historical developments. It is certain that, so far, one of the greatest results of the labour of man has been the levelling and overcoming of natural differences. Steppes are made fertile through irrigation and manuring; the contrast between open and forest land becomes less and less--indeed the destruction of forests is being far too rapidly and widely carried out--the acclimatisation of men, animals, and plants causes variations to disappear more and more as time passes. We can look forward to a time when only such extremes as mountains and deserts will remain--everywhere else the actions of the earth will be equalised. The process by which this is carried out may be described shortly. Man, in spite of all racial and national differences, is fundamentally quite as much of a unity as the soil upon which he dwells; through his labour more and more of this character of unity is transmitted to the earth, which, as a result, also becomes more and more uniform. [Sidenote: History from Heaven to Earth] One of the most powerful of the ties by which history is bound to Nature is that of its dependence on the ground. At the first glance any given historical development is involved with the earth only--the earth upon which the development takes place. But if we search deeper we shall find that the roots of the development extend even to the fundamental principles of the planetary system. By this it is not meant that every history must be founded on a cosmological basis, that it must begin with the creation, or, at least, with the destruction of Troy, as was once thought necessary; but it is certainly safe to say that a philosophy of the history of the human race, worthy of its name, must begin with the heavens and then descend to the earth, filled with the conviction that all existence is fundamentally one--an indivisible conception founded from beginning to end on an identical law. The 316,250,000 square miles of the earth’s surface is the first area with which history has to do. Within it all other surface dimensions are included; it is the standard for measurement of all other areas, and also comprehends the absolute limits of all bodily life. This area is fixed and immutable so far as the history of mankind is related to it, although in respect to the history of the world it is not to be looked upon as having been unalterable in the past, or as being likely to remain unchanged in the future. [Sidenote: 316,250,000 Miles of History] The earth’s surface may be divided into three unlike constituent parts--84,250,000 square miles of land, 220,000,000 square miles of water, and 13,750,000 square miles of ice-covered, and for the greater part unexplored, land and sea in the Northern and Southern Polar regions. The land is the natural home of man, and all his historical movements begin and end upon it. The size of states is computed according to the amount of land which they include; their growth has derived its nourishment from the 84,250,000 square miles of earth as from a widespread fundamental element. The sea is not to be looked upon as an empty space between the divisions of land, merely separating them one from another, for the 220,000,000 square miles of water are also of historical importance, and the area of every ocean and of every portion of an ocean has its historical significance. History has extended itself over the sea, from island to island, from coast to coast, at first crossing narrow bodies of water, later broad oceans; and states whose foundations arose from connections by sea remain dependent on the sea. The Mediterranean held together the different parts of the Roman Empire just as the oceans unite the Colonies of the British Empire. The variations of the earth’s form from that of a perfect oblate spheroid are so small that they may be entirely disregarded from the point of view of history. All portions of the earth’s surface may be looked upon as of equal curvature; the pyriform swelling which Columbus believed to be a peculiarity of the tropic zones in the New World was merely an optical illusion. Thus all portions are practically similar, and uniformity obtains over the entire earth to such an extent that there is room left only for minor inequalities in configuration. To these belong the differences in level between lands and seas, highlands and lowlands, mountains and valleys. Such variations amount to very little when compared with the earth as a whole; for the height of the tallest of the Himalayas added to the earth’s radius would increase its length by about 1/700 only; and the same may be said of the greatest depressions beneath the level of the sea--inequalities that cannot be represented on an ordinary globe. Their great historical significance is due chiefly to the fact that the oceans and seas occupy the depressions, from which the greatest elevations emerge as vast islands. [Sidenote: Irregular Surface of the Earth] The remaining irregularities of the earth’s surface are not sufficient to produce any permanent variations in the diffusion of races or of states. Their influence is merely negative; they may only hinder or divert the course of man in his wanderings. Even the Himalayas have been crossed--by the Aryans in the west, and by the Tibetans in the east; and British India has extended its boundaries far beyond them to the Pamirs. The historian is concerned with but two of the variable qualities of the land--differences in level and differences in contour. Variations in constitution, development, elementary constituents, and the perpetual phenomena of transformation and dissolution which present a thousand problems to the geographer, scarcely exist for the historian. Nor are those great inequalities, the depressions in which the seas rest, of any interest to him. It is indifferent whether the greatest of such depressions be covered by five miles of water, or, as we now know, by almost six miles. The fact that the Mediterranean reaches its greatest depth in the eastern part of the Ionian Sea has nothing whatever to do with the history of Greece. [Sidenote: Depths of The Sea] To be sure, there is a general connection between the depth of the Mediterranean, shut up within the Straits of Gibraltar, and the climate of the neighbouring regions, which has a direct influence on the inhabitants of Mediterranean countries; but it is a very distant connection, and it is only mentioned here in order to remind the reader that there is not a single phenomenon in Nature that is not brought home to mankind at last. Still, as a rule, history is concerned with the depths of the sea only in so far as they are the resting-places for submarine telegraph cables; and this is a fact of very recent times. It may be said that the formation of the earth’s crust occurred at a period too remote to have had any influence on the history of man, and that therefore all questions concerning it should be left to geology. The first statement may be admitted, but the latter does not follow by any means; for if the whole Mediterranean region from the Caucasus to the Atlas Mountains, and from the Orontes to the Danube, is a region of uniform conformation, it is purely by reason of a uniformity in development. In the same manner there is an extensive region of uniform conformation to the north, between the Atlantic Ocean and the Sudetic Mountains in Austria. [Sidenote: Nature Divides and Unites] There are great features of the earth’s conformation that are so extensive that groups of nations share them in common. Russia and Siberia occupy the same plain upon which the greater portions of Germany, Belgium, and Holland are situated. Germany and France share the central mountain system which extends from the Cévennes to the Sudeten, or Sudetic Mountains. A mere participation in a common geological feature produces such affinity and relationship as may be seen in the Alpine states, in Sweden and Norway, and in the nations of the Andes. This reminds us of the groups of nations that surround seas; but that which separates the Baltic states binds them together; and the mountains that unite the Swiss cantons also separate them from one another. Lesser features of conformation divide countries and often exhibit gaps and breaches in development, for the reason that they divide a political whole into separate natural regions. The history of the lowlands of North Germany differs greatly from that of the mountainous districts of the same country; the lowlands of the Po and Apennine Italy are two different lands. The great contrast between the hilly manufacturing west of England and the low-lying agricultural east extends throughout English history; and in like manner the highlands and the lowlands are opposed to each other in Scotland. [Illustration: SCENERY THAT SHAPES CHARACTER: THE INFLUENCE OF THE MOUNTAINS The stories of mountain peoples are very similar; the Highlanders of Scotland, Wales, Switzerland, the Cevennes, and Tyrol, have many characteristics in common, owing their rugged nature and independence to environment. ] Wherever mountain formations occur largely in a country, the question arises whether, in spite of all diversity, they unite to form a whole, or whether they exist as separate, independent neighbouring parts. The elements of the surface formation of the earth are not only historically important in themselves as units, but also on account of the way in which they are connected with one another. We have in Greece an example of an exceedingly intricate mountain system in which barren plateaus are interspersed with fertile valleys and bays. Owing to the sea, such bays as those of Attica, Argos, and Lamia are to a high degree self-dependent; they became little worlds in themselves, independent states, which could never have grown into a united whole had they not been subjected to external pressure. The reverse of this state of disunion, arising from the juxtaposition of a great number of different formations, is the division of North America into the three great regions of the Alleghanies, the Mississippi Valley, and the Rocky Mountain plateau, which gradually merge into one another and are bound into a whole by the vast central valley. Austria-Hungary includes within itself five different mountain features--the Alps, Carpathians, Sudeten, the Adriatic provinces, and the Pannonian plains. Vienna is situated where the Danube, March, and Adria meet, and from this centre radiates all political unifying power. If a still closer-knit unity is co-existent with a diversified geological formation of insular or peninsular nature, as in Ireland or Italy, it follows that this unity binds the orographic divisions into an aggregate. The discrepancies between Apennine Italy, Italy of the Po Valley, and Alpine Italy, which have been evident in all periods of history, formed, in their rise and in their final state of subjugation to political force, an example of dissimilarity of mountain features existing within peninsular unity. The great continental slopes are also important aids to the overcoming of orographic obstacles to political unity. In Germany there is a general inclination towards the north, crossed and recrossed by a number of mountain chains and successions of valleys. It is not to be denied that the intersecting elevations have furthered political disunion. Without doubt, a gradual slope from the southern part of Germany to the sea, with a consequent partition of the country by the rivers into strips extending from east to west, would have been attended by a greater political unity. Again, but in another way, the preponderance of any one orographic element has a unifying effect on all the other elements, as we have seen in North America, where the simple, even course of development has been in conformity with the existence of geological formations on a large scale. [Illustration: THE SOFTENING EFFECT OF THE RICH AND FRUITFUL LOWLANDS Whereas mountains breed independence and rugged character in their inhabitants, the more fruitful lowlands develop a gentler race, loving the companionship of communities. The lowlands, also, are the homes of mixed races. ] There are internal differences in formation in every mountain range and in every plain, all of which have different influences on history. The steep fall of the Alps on the Italian side has rendered a descent into the plains of the Po far easier than a crossing in the opposite direction, where many obstacles in the shape of mountain steeps, elevated plateaus, and deep river valleys surround the outer border of the Alps. Again, penetration from the plains to the interior of the Alps is less difficult in the west, where there are no southern environing mountains, than in the east, where there is such a surrounding mountain chain. The compact formation of the Alps in the west crowds obstacles together into a small space, where they may be overcome with greater labour and in a shorter time than in the east, among the broadened-out chains of mountains, where there are numerous smaller hindrances to progression spread out over a wider territory. The route from Vienna to Trieste is twice as long as that from Constance to Como. In mountain passes orographic differences are concentrated within very limited areas, and for this reason passes are of great importance in history. The value of gorges and defiles increases with their rarity, and their number varies greatly in different mountain chains. The Pindus range is broken but once, by the cleft of Castoreia, and an easy passage from Northern to Central Greece is possible only by way of Thermopylæ; the short overland route from Persia to India is through the Khyber or Bolan Passes. The Rhætian Alps are rich in defiles and gorges; but the mountain ridges are poor in crossing-places, and, as a rule, the elevation of the passes decreases towards the east. [Sidenote: Nature’s Place in History] The possibility of journeying over the Himalayas increases as we travel westward. During the Seven Years’ War the great difference between the accessible, sloping Erz-Gebirge of the Bohemian frontier and the precipitous, fissured, sandstone hills of the Elbe was very apparent. Mountain passes are always closely connected with valleys and rivers; the latter form the ways leading to and from the former. The valleys of the Reuss and the Tessin are the natural routes to the pass of St. Gothard; and were it not for the gorges of the Inn and the Etsch in the northern and the southern Alps, the Brenner Pass would not possess anything like its present supreme importance. Wherever such entrances to passes meet together or cross one another, important rallying-points either for carrying on traffic or for warlike undertakings are formed; such places are Valais, Valteline, and the upper valley of the Mur. Coire is a meeting-point of not less than five passes--the Julier, Septimer, Splügen, St. Bernardin, and Lukmanier. The value of passes varies according to whether they cross a mountain range completely from side to side, or extend through only a part of it. When the Augsburgers, on the way to Venice, had got through the Fern Pass, or that of Leefeld, the Brenner still remained to be crossed; but when the Romans had surmounted the difficulties of Mont Genevre, the ridges of the Alps were no longer before them; they were in Gaul. There are also passes through cross ridges that connect mountain chains, such as the Arlberg, that pierces a ridge extending between the northern and the central Alps. Passes of this sort are of great importance to life in the mountains, for, as a rule, they lead from one longitudinal valley to another, such valleys extending between ridges being the most fertile and protected districts in mountainous regions. In this manner the Furka Pass connects Valais, the most prosperous country of the Alps during the time of the Romans, with the upper Rhine valley; and the Arlberg connects the Vorarlberg with the upper valley of the Inn. [Sidenote: Value of Mountain Passes] Mountain passes are not only highways for traffic, they are the arteries of the mountains themselves. Commerce along the mountain ways leads to settlements and to agriculture at heights where they would hardly have developed had it not been for the roads; and the highest permanent dwellings are situated in and about passes. The Romans established their military colonies in the neighbourhood of passes, and the German emperors rendered the Rhætian gorges secure through settlements. There are political territories that are practically founded on mountain passes. The kingdom of Cottius, tributary to the Romans, was the land of the defiles of the Cottian Alps; Uri may be designated as the country of the north Gothard, and the Brenner Pass connects the food-producing districts of the Tyrol with one another. [Sidenote: Battlefields of Mountain Borderlands] The transition point from one geological formation to another is invariably the boundary line between two districts that have different histories. The movements in one region bring forces to bear on the movements in the other. Hence the remarkable phenomena which occur on mountain borderlands. The historical effects of mountainous regions are opposed by forces that thrust themselves in from without; external powers anchor themselves, as it were, in the mountains, seeking to obtain there both protection and frontier lines. Rome encroached more and more upon the Alps, first from the south, and then from the west and the north, by extending her provinces. Austria, Italy, Germany, and France have drawn up to the Alps on different sides; they merely fall back upon the mountains, however; their centres lie beyond. The same phenomenon is shown in the regions occupied by different races. Rhætians, Celts, Romans, Germans, and Slavs have penetrated into the Alps; but the bulk of their populations have never inhabited the mountainous districts. The question as to which nation shall possess a mountain chain or pass is always decided on the borders. Here are the battlefields; here, too, are the great centres of traffic whose locations put one in mind of harbours situated at points where two kinds of media of transmission come into contact with each other. This margin, like that of the sea, also has its promontories and bays. [Illustration: THE BANDIT’S WIFE The effect of life in the hills is clearly seen in this picture by Leopold Robert, who painted it after living among the “Brigands of the Mountains” and studying their wild and picturesque life. The association of peoples with mountains develops a rugged character and gives that strength and independence which mountain races have displayed in history. ] Height of land obstructs historical movements and lengthens their course. The Romans remained at the foot of the Alps for two centuries before they made their way into them, forced to it by the constant invasion of Alpine robbers who descended from the heights as if sallying forth from secure fortresses. Long before this the Romans had encircled the western side of the Alps and had begun to turn the eastern side. The colonies on the Atlantic coast of America, the predecessors of the United States, had been in existence for almost two hundred years before they passed the Alleghanies; and it is certain that this damming up of the powerful movement towards the west, which arose later, had a furthering influence on the economic and political development of the young states. The passes of the Pyrenees occur at about two-thirds of the distance from the level ground to the summits of the mountains; in the Alps the elevation of the gorges is but one-half or one-third that of the mountain tops; hence, as a whole, the Alps are more easy of access than the Pyrenees. The Colorado plateau is a greater obstacle than the Sierra Nevada range in California, which, although of much greater elevation, slopes gently and is interspersed with broad valleys. It was due rather to the forests than to the moderate elevation of the central mountains of Germany that their settlement was delayed until the twelfth and thirteenth centuries. The influence of the broad, desert tableland of the great basin in separating the western from the Mississippi states is greater than that of the Rocky Mountains with peaks more than twelve thousand feet in height. The extensive glacial formations and the sterility of the mountains in Scandinavia have held Sweden and Norway asunder, and at the same time have permitted the Lapps and their herds of reindeer to force themselves in between like a wedge. The broad, elevated steppes of Central Tien-schan enabled the Kirghese to cross the mountains with their herds and to spread abroad in all directions. [Sidenote: Little Worlds on the Heights] [Sidenote: Man in Touch with Nature] In such cases the natives of tablelands and mountainous regions, who inhabit little worlds of their own on the heights, themselves contribute not a little towards rendering it difficult to pass through their countries. The most striking example of this is Central Asia with its nomadic races, whose influence in separating the great coast-nations of the east, west, and south from one another has been far more potent than that of the land itself. And these nomads are a direct product of the climate and the soil of this greatest plateau in the world. The dry tablelands of North America, from the Sierra Madre in Mexico to Atacama in the south, were in early times inhabited by closely related races, having more or less similar institutions and customs. A like effect of life on plateaus, shown in the Caucasus Mountains, that have preserved their character as a barrier against both Romans and Persians, and have been crossed by the Russians only in recent times, points to a further reason for the sundering influence of the wall-like position of mountains between the steppes and the sea. Phenomena similar to those observed in Central Asia and in North America occur on a smaller scale in every mountainous country--extensive uninhabited tablelands in which man and free nature come into direct contact with each other. Independent development is thus assured to the dwellers on mountains, and to their states a preponderance of territory over population. The political importance of Switzerland is not owing to its three millions of inhabitants, but to the impossibility of occupying one-fourth of the Alps. The position--almost that of a Great Power--held by Switzerland during the fifteenth and sixteenth centuries was due to the union of this element of strength (and the fact that Switzerland, by reason of its situation, includes many of the most important commercial routes in Europe) with the mountain-bred spirit of liberty and independence of its people. In other respects, too, mountain states stand pre-eminent among nations--as Tyrol outshone all other Austrian provinces in 1809, so the mountain tribes of the Caucasus were the only Asiatics able to offer any permanent resistance to the advance of the Russians. The broad, rough character of a highland country is an active force; in all mountain wars it has led to the spreading out of armies and to the lengthening of columns. [Sidenote: Mountains the Friends of Weak Nations] The support afforded by mountains to weak nations that without the protection of a great uninhabited region would not have been able to maintain their independence can be likened only to the protection which, as we have seen, is given by the sea. Switzerland has often been compared to the Low Countries; and there is even a still greater resemblance between city cantons such as Basle and Geneva and ports like Hamburg and Lübeck. It was owing to similar reasons that the strongholds of French Protestantism during the sixteenth century were the Cévennes, Berne, and La Rochelle. The protection given by mountains must not be looked upon as of an entirely passive nature, for the rugged nature of mountaineers, and their concentration within small areas where a development is possible, rendering them conscious of independence and assisting them to preserve it, are also a result of life in the highlands. In low-lying countries difference in levels cannot exceed a thousand feet; and, as the variations in conformation are correspondingly small, the lowlands offer fewer hindrances to historical movements than do rivers, seas, and marshes--thus there is a greater opportunity for the development of such movements upon the plains. Consequently there is a rapid diffusion of races over extensive regions whose boundaries are determined by area rather than by conformation. [Sidenote: Effect of Mountains on People] Lowlands hasten historical movements. There is no trace of the retarding and protecting effects of the highlands in lands where, as Labu said of Saxony, a nation dwells together with its enemies on the same boundless level. Nomadism is the form of civilisation characteristic of broad plains and extensive tablelands. But the Germanic races of history, a great part of which were no longer nomads, exhibited a hastening in their movement towards the west when they reached the lowlands; for they appeared on the lower Rhine at an earlier time than on the upper Rhine, delayed in their wanderings towards the latter by the mountainous, broken routes. Long after the Celts had disappeared from the lowlands, when their memory only was preserved in the names of hills and rivers, they still continued to exist in the protected mountain regions of Bohemia. In like manner, in later times, the Slavs maintained themselves in natural strongholds after they had vanished from the plains of Northern Germany. Compare the conquest of Siberia, accomplished in a century, with the endless struggles in the Caucasus. And what lowland country can show remnants of people equivalent to those of the Caucasus? [Sidenote: The Natural Strongholds of Nomad Races] The lowlands are also regions of the most extensive mingling of races. We have but to think of Siberia or the Sudan. In the development of states, lowlands take precedence over mountainous district. Rome expanded from the sea-coast to the Apennines, and from the valley of the Po to the Alps; the conquest of Iberia began in the one great plain of the peninsula, in Andalusia, and in the lowlands of the Ebro; and foreign control of Britain ended at the mountains of Scotland and Wales. In North America colonisation spread out in broad belts at the foot of the Alleghanies before it penetrated into the mountains. In Southern China the mountains with their unsubdued tribes are like political islands in the midst of the Mongolised hills and plains. The lesser the differences in level, and the smaller the conformations of the earth, the more important are those differences that remain within heights of less than a thousand feet above the sea. Elevations of a dozen yards were of the greatest importance on the battlefields of Leipzig, Waterloo, and Metz. The significance of the little rise in the land of Gavre, near Ghent, lies in the fact that even at times of flood a foundation for a bridge will remain firm upon it. The slightest elevation in the lowland cities of Germany and Russia offers such a contrast in altitude to its surroundings that a fortress, a cathedral, or a kremlin is erected upon it. The two ridges that extend through the plains of North Germany are not only very prominent in the landscape, but also in history. Owing to their thick forests, their lakes and marshes, and small populations, they are peculiarly like barriers; and the breaches in them are of importance to the geography both of war and of commerce. The battles fought against Sweden and Poland, round about the points where the Oder and the Vistula cross these regions, are to be counted among the most decisive struggles in the history of Prussia. [Sidenote: Nature at Waterloo] Wherever there are no differences in level, a substitute is sought in water. In such cases wide rivers or numerous lakes and marshes form the most effective obstacles, boundaries, and strongholds. Finally the plains approach the sea and are submerged by it; and here lowland countries find a support safer than that of the mountains, and richer in political results. North Germany is supported by the sea; South Germany by mountains. Which boundary is the more definite, the more capable of development, politically and economically? Political superiority is ever connected with the protection and support of the sea. The influences of vegetation upon historical movements are often more important than those of the earth-formation itself. Wherever extensive lowland regions are overgrown with grass, we always find mobile nomadic races that, with their large herds and warlike organisations, are great causes of disturbance in the development of neighbouring lands. Since the form of vegetable growth which covers grass steppes and prairies is dependent on climate, it follows that nomadism is prevalent throughout the entire northern sub-temperate zone, where such grass is abundant--from the western border of Sahara to Gobi. Nomadic races of historical significance are even to be seen in the New World--for example, the Gauchos of the Pampas, and the Llaneros of Venezuela. [Illustration: THE GREATEST PLATEAU IN THE WORLD: ITS PEOPLE, AND ITS INFLUENCE IN HISTORY This is a typical scene of life in Central Asia, the greatest plateau in the world, whose people, the direct product of the climate and the soil, inhabiting little worlds of their own on the heights, have exercised an enormous influence in separating the great coast nations of the east, west, and south from one another. ] [Illustration: A MOUNTAIN PASS: A NATURAL FACTOR OF VAST IMPORTANCE IN HISTORY Mountain passes have been of great importance in history. The Romans established their military colonies in the neighbourhood of passes, and there are political territories practically founded on mountain passes. This is a picture of an entrance to the famous Bolan Pass, through which, and through the Khyber Pass, lie the shortest overland routes from Persia to India. ] [Illustration: NOMADIC PEOPLES OF THE NEW WORLD Wherever there are vast lowland countries covered with grass, nomadic peoples are found moving from place to place with their herds. There are many such peoples in the Old World and a few in the New World, notable among the latter being the Gauchos of the Pampas, types of whom are here seen. ] In comparison with plains and prairies, forests are decided hindrances to historical movements. Peoples are separated from one another by strips of woodland; the state and the civilisation of the Incas ceased at the fringe of primeval forest of the east Andes. Thickly-wooded mountains present the most pronounced difficulties to historical movements. The appearance of the oldest large states and centres of culture on the borders of steppes, in the naturally thinly-wooded districts at the mouths of rivers, and on diluvial plains, seems natural enough to us when we think of the difficulties presented by life in a forest glade to men who had only stone implements and fire at their command. A description of the difficulties encountered during Stanley’s one hundred and fifty-seven days’ journey through the primeval woods of Central Africa gives us a very clear conception of what are termed “hindrances” to historical movements. The early history of Sweden has been characterised as a struggle with the forest; and this description is valid for every forest country. The forest divides nations from each other; it allows only small tribes to unite, and creates but small states, or, at the most, loosely bound confederations. It is only where a great river system forms natural roads, as in the regions of the Amazon and the Congo, that great forest districts may be rapidly united to form a state. In other cases settlements in forest clearings and road-breaking precede political control. In this way the Chinese conquered the races of the western half of Formosa in two hundred years; in the eastern half the land is still under forest and the natives have also retained their independence. The existence of small states, with their many obstacles to political and economic growth, still continues in forest regions alone; and the roaming hordes of hunters inhabiting them belong to the simplest forms of human societies. [Illustration: THE MAKING OF THE NATIONS--II Professor FREDERICK RATZEL] LAND AND WATER AND THE GREATNESS OF PEOPLES Since man is a creature capable only of life on land, bodies of water must at one time have been the greatest obstacles to his diffusion. Thus the original family of human beings could have inhabited only one portion of the earth, to which it was restricted by impassable barriers of water. We know that in early geological times the division of the earth’s surface into land and water was subject to the same general laws as to-day; therefore such a portion of the earth could not have been more than a part of the total land in existence--a larger or smaller world-island. [Sidenote: Early Man’s Greatest Invention] The first step beyond the bounds of this island was the first step towards the conquest of the whole earth by man. The first raft was therefore the most important contrivance that man could have invented. It not only signified the beginning of the acquisition of all parts of the earth to their very farthest limits, but also--and this is far more important--the potentiality for all possibilities of divergence and temporary separation offered by our planet. It brought with it escape from the development that always turns back upon itself, travelling in a circle, and the progress that constantly consumes itself--factors inseparable from life confined within a small area; it led to the creation of fruitful contrasts and differences, and to wholesome competition--in short, to the beginning of the evolution of races and peoples. Looked at from this point of view, even the discovery of Prometheus has been of less moment to the progress of mankind than that of the inventor who first joined logs together into a raft and set out on a voyage of discovery to the nearest islet. [Sidenote: Why the Sea is Important] From the time of this first step onward, the development of the human race was so intimately connected with the uninhabitable water that one of its most powerful incentives lay in the struggle with the sea. And so little have we advanced from this condition that the stoutest race of the present day is one that from a narrow island commands the ocean. England’s strength is a proof of the tremendous importance of the sea as a factor of political power and of civilisation. But not to exaggerate the significance of the ocean, we may at the same time remember that it consists in the fact that, by means of the sea, open highways are presented from land to land. Command of the sea is a source of greatness to nations, for it facilitates dominion over the land. By reason of its consistency the water is an important agent of levelling and equalising effects. As we perceive this in Nature, so do we also in history. A race familiar with the sea in one place is familiar with it in all regions. The Normans off the coast of Finland, and the Spaniards in the Pacific, found the same green, surging element, moved by the same tides, subject to the same laws. The ocean has an equalising effect upon the coasts even; the dunes of Agadir and of the harbour at Vera Cruz awaken memories of home in the mind of the sailor from Hela. The diffusion of the sea over three-quarters of the earth’s surface must also be taken into account. Thus the influence of the ocean in rendering men familiar with different parts of the world is far greater than that of the land. From the ocean comes a constant unifying influence which ever tends to reduce the disuniting effect of the separation of land from land. As yet no attempt to extend boundaries beyond the land out over the sea has been followed by lasting success. [Sidenote: No Nation can Possess the Sea] [Sidenote: The Sea’s Unifying Influence] No nation can or ever will possess the sea. Carthage and Tarentum wished to forbid Italian vessels the passage of the Lacinian capes by treaty; the Venetians desired dominion over the Adriatic to be granted them by the Pope; Denmark and Sweden strove for a dominion over the Baltic Sea; but all this is against the very nature of the sea; it is one and indivisible. Only near by the coast, within the three-mile limit of international law, and in landlocked bays, may it be ruled as land is ruled. The claims of the Americans concerning the sovereignty of Behring Sea have never been recognised, and England can retain dominion over the Irish Sea only by means of her naval power. The ocean has a unifying influence on the land, even when this influence consists only in the same ends to be attained being placed before different nations. During a time of the greatest disunion, German cities that lay far enough from one another were united by Baltic interests. The union of scattered land-forces prepared the way for the opening up of wider horizons to England in the sixteenth century in the same manner as for Italy and Germany in the nineteenth. [Illustration: THE LITTLE ISLAND THAT RULES THE SEA The command of the sea is the source of national greatness, as it facilitates dominion over land. England from a narrow island dominates the sea. The tiny part of white in the Eastern Hemisphere on this page shows how relatively insignificant Great Britain is to the vast world of waters where her shipping is supreme.] Sea power is far more closely connected with traffic than is land power; in fact, the foundation of sea power is trade and commerce. It is, however, more than mere commercial power and monopoly of trade. In spite of all egoism, greed, and violence there remains one great characteristic peculiar to maritime Powers, spared even by Punic faith and Venetian covetousness. Even the neighbourhood of the ocean is characterised by its vast natural features; rivers broaden as they approach the sea, great bays lie within the coasts, and, though the latter may be flat, the horizon lines of their low dune landscapes are broad. The horizons of maritime races are also broad. Whether it be the hope of profit from commerce or of gain from piracy that lures men forth, many a ship has returned to port bearing with it inestimable benefits to mankind; for the greatest maritime discoveries have not been mere explorations of new seas, but of new lands and peoples. Such discoveries as these have contributed most to the broadening of the historical horizon. Even political questions expand, assume a larger character, and often become less acute, when they emerge from the narrow limits of continental constraint upon the free and open coasts. This is true even of the Eastern Question, to the solution of which definite steps were taken upon the Mediterranean when it seemed to have come to a deadlock in the Balkan peninsula. [Sidenote: Short-lived Nations of the Sea] [Sidenote: The Fall of Maritime Nations] The ocean is no passive element to maritime races. By deriving power from the sea they become subject to the sea. The more strength they draw from the ocean, the less firm becomes their footing upon the land. Finally, their power no longer remains rooted in the land, but grows to resemble that of a fleet resting upon the waves; it may with but small expenditure of effort extend its influence over an enormously wide area, but it may also be swept away by the first storm. As yet all maritime nations have been short-lived; their rise has been swift, often surprisingly so; but they have never remained long at the zenith of prosperity, and, as a rule, their decay has been as rapid as their elevation to power. The cause of the fall of all maritime nations has been the smallness of their basis, their foreign possessions, widely separated from one another and difficult to defend, and their dependence upon these foreign possessions. In many cases the over-balancing of political by economic interests, the neglect of materials for defence, and effeminacy resulting from commercial prosperity, have also contributed to their destruction. [Illustration: MAN’S FIRST STEP TOWARDS THE CONQUEST OF THE EARTH The most momentous event in the early history of man was the launching of the first raft. That moment was instinct with all the mighty conquests and discoveries yet to be accomplished over seas; and even the discovery of fire, says Professor Ratzel, has been of less moment to the progress of mankind than that of the inventor who first joined logs together into a raft and set out on a voyage of discovery to the nearest islet. ] Special combinations of characteristics arising from the geographical positions of oceans, continents, and islands are connected with the broad features common to oceanic continuity. These characteristics are reflected from the sea back to the land, and there give rise to historical groups. The historical significance of such groups is expressed in their names even--Mediterranean World, Baltic Nations, Atlantic Powers, and Pacific Sphere of Civilisation. They are primarily the results of commerce and exchange, and of the furthering, correlating influences of all coasts and islands. When they united all peninsulas, islands, and coasts of the Mediterranean into one state the Romans merely set a political crown upon the civilised community that had developed round about, and by means of, this sea. [Sidenote: Uniqueness of the Mediterranean] And if we wish rightly to estimate the significance of Roman expansion from a Central European point of view, we may express our conception very shortly--the diffusion of Mediterranean culture over Western and Central Europe. It was at the same time a widening of the horizon of a landlocked sea to that of the open ocean. The Atlantic Ocean succeeded to the Mediterranean Sea. The Americans and the Russians, and the Japanese, repeating their words, maintain that in the same manner the Pacific must succeed to the Atlantic; but they forget the peculiar features of the Mediterranean, especially its conditions of area. It is no more probable that such a compact, isolated development will occur again than that the history of Athens will repeat itself on the Korean peninsula or at Shantung. The greater the ocean, the farther is it removed from the isolated sea. It was not the Atlantic that succeeded to the Mediterranean, but the broad world-ocean that succeeded to the narrow basin called the Mediterranean Sea. There have always been differences between the various divisions of the main sea; and these variations will ever continue to be prominent, although constantly tending to become less and less so. [Sidenote: The vast Potentialities of the Pacific] The Pacific will always remain by far the greatest ocean, including, as it does, forty-five per cent. of the total area of water. Owing to its great breadth, the Pacific routes are from three to four times as long as those of the Atlantic. The Pacific widens toward the south; and Australia and Oceania lie in the opening, thus furnishing the Pacific with its most striking peculiarity--a third continent situated in the Southern Hemisphere, together with the richest series of island formations on earth. Whatever the Pacific may contribute to history, it will be a contribution to the annals of the Southern Hemisphere; and if a great independent history develop in the antipodes, it will have the Southern Pacific, bounded by Australia, South America, New Zealand, and Oceania, for its sphere of action. The area of the Atlantic Ocean is but half that of the Pacific. Nor is it for this reason alone that in comparison with the latter it is an inland rather than a world sea; for, owing to its narrowness between the Old and the New Worlds, the branches it puts forth, and the islands and peninsulas that it touches, it shortens the routes from one coast to the other. In it there is more of a merging of land and sea than a separation; and to-day it is chiefly a European-American ocean. The Indian Ocean is both geographically and historically but half an ocean. Even though important parts of it may be situated north of the equator, it is too much enclosed to the north; it widens to the south, and thus belongs to the Southern Hemisphere. [Illustration: A STORM SUCH AS MAY SWEEP AWAY A NATION’S POWER All maritime nations, says Professor Ratzel, have been short-lived. The more strength they draw from the ocean the less firm becomes their footing upon the land, and their power grows to resemble that of a fleet resting upon the waves; it may extend its influence over an enormous area, but it may also be swept away by a single storm. ] [Sidenote: The Coast the Threshold of the Land] The great oceans open up broad areas for historical movements, and through their instrumentality peoples are enabled to spread from coast to coast in all directions; the inland seas, on the contrary, cause the political life of the nations bordering upon them to be concentrated within a limited area. The Mediterranean will ever remain a focus towards which the interests of almost all European Powers concentrate. It has, moreover, become one of the world’s highways since the completion of the Suez Canal. The Baltic somewhat resembles the Mediterranean; but it would be saying too much to look upon its position as other than subordinate to that of the greater sea. The area of the Baltic is but one-seventh that of the Mediterranean; and it is lacking in the unique intercontinental situation of the latter. In many respects it resembles the Black Sea rather than the Mediterranean, especially by reason of its eastern relations. Originally the coast was the threshold of the sea; but as soon as maritime races developed it became the threshold of the land. In addition it is a margin, a fringe in which the peculiarities of sea and land are combined; and for this very reason sea-coasts have a historical value greatly disproportionate to their area, especially as they constitute the best of all boundaries for the nations that possess them. Here harbours are situated, fortresses, and the most densely populated of cities. Owing to their close connection with the sea, the inhabitants of coasts acquire characteristics which distinguish them from all other peoples. Even if of the same nationality as their inland neighbours--as, for example, the Greeks of Thrace and of Asia Minor and the Malays of many of the East Indian islands--their foreign traffic nevertheless impresses certain traits and features upon them which in the case of the Low Countries led almost to political disruption. [Sidenote: Living and Dead Coasts] A coast is more favoured than an interior in all things relating to commerce and traffic; yet neither may enjoy permanent life alone without the other. The French departments of the Weser and of the Elbe were among the most ephemeral of the political results achieved by the short-lived Napoleonic era. With the sea at their backs it is easy for the inhabitants of a coast to become detached from their nation, and but a simple matter for them to spread over other coasts. Ever since the time of the Phœnicians there have been numerous colonists of coasts and founders of coast states. The Normans are most typical in European history. The expansion of coast colonies towards the interior is one of the most striking features of recent African development. Thus coasts are to be looked at from within as well as from without. To many races--such as Hottentots and Australians--the coast is dead compared with the interior; for Germany the coast has been politically dead for centuries. A river-mouth is best suited to carrying the influences of the coast inland. All ancient historians supposed that the Mediterranean Sea, with its many bays, peninsulas, and islands, schooled the Phœnicians in seamanship. This, however, is not so. Nautical skill is transmitted from one people to another, as may be seen from some of the most obvious cases in modern history. No maritime people has become great through its own coast alone. It is not the coast of Maine, with its numerous inlets and bays, that has produced the best seamen, but the coast of Massachusetts, naturally unfavourable for the most part; and it has produced the best seamen for the reason that the inland districts bounded by it are far more productive and furthering to commerce than are the interior regions of Maine. [Sidenote: The Place of the Coast in History] Nature has forced races to take to the sea only in such countries as Norway and Greece, where the strips of coast are narrow and the inland territory poor. In order to have political influence it is sufficient to have one foot on the sea-coast. Aigues-Mortes, with its swampy environment, was sufficient to extend France to the Mediterranean during the reign of St. Louis; Fiume sufficed for Hungary. Forbidding desert coasts have had a peculiarly retarding effect on historical development. It was necessary to rediscover the Australian mainland, to touch at more favourable points, one hundred and thirty years after the time of Tasman; thus the history of the settlement of Australia by Europeans originated, not with him, but with Cook. As portions of the general water area, rivers are branches or runners of the sea, extending into the land--lymphatic vessels, as it were, bearing nourishment to the ocean from the higher regions of the earth. Therefore they form the natural routes followed by historical movements from the sea inland and vice versa. A solid foundation of truth underlies those rivers of legendary geography that joined one sea with another. The connection of the Baltic and the Black Sea via Kieff is not that described by Adam of Bremen; but Russian canals have established a water-way, following out the plan indicated by Nature, just as the Varangians also realised it in a ruder way by dragging their boats from the Dwina to the Dnieper. By uniting the Great Lakes to the Mississippi by means of the Illinois River, the French provided a waterway from the North Atlantic Ocean to the Gulf of Mexico, a line of power in the rear of the Atlantic colonies. The latter fell back on salt water, the former on fresh. The Nile, flowing parallel to the Red Sea from Tanasee in the Abyssinian highlands, shares with the Red Sea even to-day in the traffic between Eastern and East-central Africa. The railway from Mombasa to Uganda completes a western Mediterranean-Indian line of connection, as a road along the Euphrates to the Persian Gulf would an eastern, each following the direction of rivers running parallel to the Red Sea. We can clearly see the transition of the functions of oceans to fresh, shallow water, to sounds and lagoons, in which sea traffic is furnished with smoother, quieter routes under the shelter of the coasts. [Illustration: THE OCEANS OF THE WORLD This map, on a projection used by mariners, shows the relative sizes of the great oceans, viewed from above. The natural advantage of the position of the British Isles for communicating with the ocean’s highways is clearly seen, and the vast area of the Pacific is strikingly indicated. ] In truth, only portions of the lines of traffic follow rivers; for rivers flow from highland to lowland, watersheds breaking their course here and there. In comparison with the oceans, rivers are but shallow channels, the continuity of which may be broken by every rocky ledge. Thus different regions for traffic arise at various points in the same stream. Only that part of Egypt which is situated north of the first cataract is Egypt proper; the territory to the south was conquered from Nubia. The farther we travel up a stream the less water and the more rapids and falls we shall find; therefore traffic also decreases in the direction toward the river’s source. It may be seen from this that there is but little probability of truth in the analogy drawn between the flowing of rivers from elevations to plains and the migrations of nations and directions in which states expand. History shows that migration and development follow a direction contrary from that in which rivers flow. Maritime and terrestrial advantages are concentrated where a river joins the sea; especially characteristic of such districts are deltas, at an early date rendered more efficient for purposes of commerce through canals and dredging. The fertility of the alluvial soil, the lack of forest occasioned by frequent floods, and the protection afforded by the islands of the delta, may have had not a little influence on the choice of such regions as settlements for man. At all events, estuaries and deltas, both small and great, were in the earliest times centres of civilisation. Egypt and Babylonia both testify to this; the colonising Greeks also showed a preference for river mouths. Miletus, Ephesus and Rome were states situated at the mouths of rivers, and so were the ancient settlements on the Rhone, the Guadalquivir, and the Indus. It would not be possible, however, to deduce from this proofs of a potamic phase of civilisation and formation of nations preceding the Thalassic, or Mediterranean. Estuary and delta states are far more a result of the Mediterranean culture. The latter led to the settlement of favourable districts on various coasts, all of which were finally swallowed up into the Roman Empire during the period of its northern and eastern expansion. [Illustration: THE ORIGIN OF SEAFARING PEOPLES It is not sufficient to have a favourable sea-coast in order to breed a race of sea-going people. The land behind the coast-line must be fertile and productive, else no inducement exists for seafaring. This condition is everywhere present along the British shores, of which this is a typical coasting scene. ] [Illustration: THE JUNCTIONS OF GREAT RIVERS ARE LANDMARKS OF HISTORY Where two rivers join, two lines of political tendencies always meet, and their junction is the point whence political forces must be controlled. This is the significance of the situations of Mainz (1 at top), Khartoum (2), Lyons (3), and Belgrade (4) Photos: Frith and Photochrome ] [Sidenote: Rivers as Highways of Development] Another much more evident process of development through the instrumentality of rivers was shown at the time when traffic began to extend itself over wide areas. Rivers are the natural highways in countries which abound in water, and are of so much the greater importance because in such lands other thoroughfares are frequently wanting. Taken collectively, rivers form a natural circulatory system. In America at the time of the exploration and conquest, in Siberia, in Africa to-day, they are natural arteries by means of which exchange and political power may be extended. The more accessible a river is to commerce, the more rapidly political occupation increases about its basin, as has been shown by the Varangians in Russia and the Portuguese in Brazil. The best example of a country having developed through conformity with a natural river system and in connection with it is that of the Congo State, with part of its boundaries drawn simply along the lines of watersheds. Mastery among rival colonies is determined by the results of the struggle for the possession of rivers; this has been as clearly shown by the St. Lawrence and the Mississippi in America, as by the Niger and the Benuwe in Africa. The influence of riverways in furthering the path of political development may be best seen in the contrast between South America and Africa; the colonising movement came to the latter more than 300 years later than to the former continent. Every river is a route followed by political power, and is therefore at the same time a point of attraction and line of direction. The Germans have pushed their way along the Elbe between the Danes and the Slavs, and along the Vistula between the Slavs and the Lithuanians or old Prussians. The river that supports an embryonic nation holds it together when developed. The influence of the Mississippi was directed against the outbreak of the Civil War in America. As pearls are strung along a cord, so the provinces of new and old Egypt are connected by the Nile. Austria-Hungary is not the Danube nation only because the river was the life nerve of its development, but also because eighty-two per cent. of Austro-Hungarian territory is included within the regions drained by it. When the natural connection of rivers is broken then this power of cohesion ceases. The political and economic disunion of the Rhine, the Main, and other German rivers preceded the dissolution of the German Empire. [Sidenote: Rivers as Sources of Power] Where two rivers join there is always a meeting of two lines of political tendencies, and the place of their junction is the point whence the political forces must be controlled and held together. This is the significance of the situations of Mainz, Lyons, Belgrade, St. Louis, and Khartoum. The course followed by flowing water is far less direct than that of historical movements; the latter take the shortest way, and do not continue along the stream where a loop is formed; or they may follow a tributary that runs on in the original direction of the main stream, as in the case of the very ancient highway along the Oder and the Neisse to Bohemia. The sides of sharp angles formed by a river in its course lead to a salient point as, Regensburg and Orléans. A tributary meeting the main stream at this point forms the best route to a neighbouring river, or the angle may become a peninsula, so bounded by a tributary stream at its base as almost to take the form of an island. [Sidenote: Rivers as Dividers of Land] Breaks in the continuity of the land occasioned by rivers are caused rather by the channel in which the water flows than by the river itself. Thus we often find that dry river-beds are effective agents of this dividing up of the land. Permanent inequalities of the earth’s surface are intensified by flowing water. Therefore a river system separates the land into natural divisions. These narrow clefts are ever willingly adopted as boundary lines, especially in cases where it is necessary to set general limits to an extensive territory. Thus Charles the Great bounded his empire by the Eider, Elbe, Raab, and Ebro. Smaller divisions of land are formed by the convergence of tributaries and main streams, and again still smaller portions are created by the joining together of the lesser branches of tributaries, these taking an especially important place in the history of wars: for example, those formed by the Rhine, Weser, Elbe, and Oder, and on a lesser scale by the Moselle, Seille, and Saar. Fords are always important; in Africa they have even been points at which small states have begun to develop. Rivers as highways in time of war no longer have the value once attributed to them by Frederick the Great, who called the Oder “the nurse of the army.” Yet rivers were of such great moment in this respect in the roadless interior of America during the Civil War that the getting of information as to water-levels was one of the most important tasks of the army intelligence department. Rivers will always remain superior to railways as lines of communication during time of war, at least in one respect, for they cannot be destroyed. [Illustration: THE MAKING OF THE NATIONS--III Professor FREDERICK RATZEL] THE INFLUENCE OF ENVIRONMENT IN THE LIFE OF NATIONS Upon the earth, with its varied configuration and formation of land and sea, are many kinds of hindrances and limits to life. The most obvious effect of natural region and natural boundary lies in the counteracting forces opposed by the earth through them to a formless and unlimited diffusion of life. Isolated territory furthers political independence, which, indeed, is of itself isolation. The development of a nation upon a fixed territory consists in a striving to make use of all the natural advantages of that territory. The superiority of a naturally isolated region lies in the fact that seclusion itself brings with it the greatest of all advantages. Hence the precocious economic and political development of races that dwell on islands or on peninsulas, in mountain valleys and on island-like deltas. [Sidenote: The Rise and Death of Isolated States] Often enough growth that originates under such favourable conditions leads to ruin. A young nation deems itself possessed of all so long as it has the isolation that ensures independence; it sees too late that the latter has been purchased at the price of a suffocating lack of space; and it dies of a hypertrophy of development--a death common to minor states. This was the cause of the swift rise and decline of Athens and of Venice, and of all powers that restricted themselves to islands and to narrow strips of coast. [Sidenote: Natural Boundaries of a State] [Sidenote: A State must Forsake its Boundaries] The more natural boundaries a state possesses, the more definite are the political questions raised by its development. The consolidation of England, Scotland, and Wales was simple and obvious, as patent as if it had been decreed beforehand, as was also the expansion of France over the region that lies between the Alps and the Pyrenees, the Mediterranean and the Atlantic Ocean. On the other hand, what a fumbling, groping development was that of Germany, with her lack of natural boundary in the east! Thus in the great geographical features of lands lie pre-ordained movements, constrained by the highest necessity--a higher necessity in the case of some than of others. The frontier of the Pyrenees was more necessary to France than that of the Rhine; an advance to the Indian Ocean is more necessary to Russia than a movement into Central Europe. Growth is soundest when a state expands so as to fill out a naturally bounded region--as, for example, the United States, that symmetrically occupy the southern half of the continent of North America, or Switzerland, extending to the Rhine and Lake of Constance. There are often adjustments of frontiers which force the territory of a nation back into a natural region, as shown in the case of Chili, which gave up the attempt to extend its boundaries beyond the Andes, in spite of its having authorisation to do so, founded on the right of discovery, the original Spanish division of provinces, and wars of independence. A favourable external form is often coincident with a favourable internal configuration which is quite as furthering to internal continuity as is the external form to isolated development. The Roman Empire, externally uniform as an empire of Mediterranean states, was particularly qualified for holding fast to its most distant provinces, by reason of the Mediterranean Sea that occupied its very centre. Everything that furthers traffic is also favourable to cohesion. Hence the significance of waterways for ancient states, and of canals and railways for modern nations. Egypt was the empire of the Nile, and the Rhine was at one time the life-vein of the empire of Charles the Great. A state does not always remain fixed in the same natural region. However advantageous they may have been, it must, on increasing, forsake the best of boundaries. Since one region is exchanged for another, the law of increasing areas comes into force. Every land, sea, river region, or valley should always be conceived of as an area that must be discovered, inhabited, and politically realised before it may exert any influence beyond its limits. Thus the Mediterranean district had first to complete its internal development before it could produce any external effect. [Sidenote: First Continent State] This internal development first took possession of the small territories, and, mastering them, turned to the greater. Thus we may see history progress from clearings in forests, oases, islands, small peninsulas, such as Greece; and strips of coast, to great peninsulas, such as Italy; isthmian situations of continental size, such as Gaul; only to come to a halt in half continents such as the United States and Canada, and continents. Europe--next to the smallest continent--has had the richest history of all, but with the greatest breaking up of its area into small divisions. Australia, the smallest continent, is the earliest to unite its parts into a continental state. Development expends all its power in bringing the areas of the three greatest land-divisions into play, and in opposing their one hundred and five million square miles to the ten and a half million of the smaller divisions; their economic action is already felt to a considerable degree. Thus there arises an alternation of isolation and expansion, which was clearly shown in the history of Rome, whose territory grew from the single city, out over the valley of the Tiber, into Apennine Italy, into the peninsula, across the islands and peninsulas of the Mediterranean, and finally into the two adjacent continents. [Illustration: THE HOTTEST PLACE IN THE WORLD IS INHABITED BY MAN No climate has triumphed over the endurance of man. Massowah, the most important town in the Italian Colony of Eritrea, in North Africa, is the hottest place in the world, but, like the coldest known place, it is inhabited. ] [Sidenote: Nature and National Destiny] The boundaries of natural regions are always natural boundaries. Although this delicate subject may be left to political geography, it is by no means to be neglected by those who are interested in history, boundary questions being among the most frequent causes of wars. In addition, boundaries are the necessary result of historical movements. In case two states strive against each other in expanding, the motion of both is impeded, and the boundary lies where the movement comes to a halt. It is in the nature of things that growing states are very frequently contiguous to uninhabited regions, not to other states. This contiguity is always a source of natural boundaries. The most natural of all arise from adjacency to uninhabitable regions: first the uninhabitable lands, then the sea. The boundary at the edge of the uninhabitable world is the safest; for there is nothing beyond. The broad Arctic frontiers of Russia are a great source of power. A high mountain range, also, may separate inhabited regions--which are always State territory--by an uninhabited strip of land. After all, the sea, marshes, rivers even, are uninhabitable zones. But traffic brings connection with it, and the Rhine, which to the Romans was a moat, especially well adapted as a defence, is now, with its thirty railway bridges and thousands of vessels plying up and down and across, far more of a highway and a means of communication than a dividing line. The position, form, and movements of the earth seem far enough removed from the deeds and destinies of peoples, yet the more we contemplate the latter, the more we are led to consider the earth’s inclination to its axis, its approximately spherical form, and its motion, which, combined, are the cause of the recurrence in fixed order of day and night, summer and winter. [Illustration: INHABITANTS OF THE COLDEST PLACE IN THE WORLD Man is the most adaptable of living creatures. There is no climate in the world in which he cannot live. The lowest temperatures taken have been at Verkhoyansk, in Siberia, but the place is inhabited by people, of whom we give a group. ] The effects of these great earthly phenomena are differently felt in every country; for they vary according to geographical location. Practically, that which most conforms to any given situation north or south of the equator is the climate of a land. Day and night are of more even length at the equator than in our country; but beyond the Polar circles there are days that last for months, and nights equally long. Scarcely any annual variation in temperature is known to the inhabitants of Java, while in Eastern Siberia Januarys of fifty degrees below freezing-point and Julys of twenty degrees above zero of Centigrade, winters during which the mercury freezes, and summers of oppressive sultriness, are contrasted with one another. [Illustration: MAN’S TRIUMPH OVER CLIMATE: THE COLDEST PLACE IN THE WORLD Just as man has established himself in the torrid heat of Massowah, so he can endure the highest degree of cold. The coldest place in the world, Verkhoyansk, of which this is a photograph, is the capital of a Siberian province. ] In our temperate region there is rain, as a rule, during all months, but as far north as Italy and Greece the year is divided into a dry and a wet season. Great effects are produced over the entire earth and upon all living creatures by the thus conditioned climatic differences. They must be considered at the very beginning of every investigation into history. Since we know that a fluctuating distribution of heat is caused by the 23½° inclination of the earth’s axis, investigation also leads us to a knowledge of further phenomena, to a consideration of the dependence of the winds and of the precipitation of heat upon this very same condition. [Sidenote: The First Question about a Country] And thus we come into contact with the thousand connecting threads by which man’s economic activity, health, distribution over the earth, even his spiritual and his political life, are inseparably bound up with the climate. Hence the first question that should be asked concerning a country is: What is its geographical situation? A land may be interesting for many other reasons besides nearness or remoteness from the equator; but that which is of the greatest interest of all to the historian is a consideration of the manifold and far-reaching effects of climate. The study of human geography teaches us that climate affects mankind in two ways. First, it produces a direct effect upon individuals, races, indeed the inhabitants of entire zones, influencing their bodily conditions, their characters, and their minds; in the second place, it produces an indirect effect by its influence on conditions necessary to life. This is due to the fact that the plants and animals with which man stands in so varied a relationship, which supply him with nourishment, clothing, and shelter, which, when domesticated and cultivated, enter his service, as it were, and become most valuable and influential assistants and instruments for his development and culture, are also dependent upon climate. Important properties of the soil, the existence of plains, deserts, and forests, also depend upon climate. Effects of climate, both direct and indirect, are united in political-geographical phenomena, and are especially manifest in the growth of states and in their permanence and strength. [Sidenote: Man can Bear all Climates] There is no climate that cannot be borne by man; of all organic beings he is one of the most capable of adapting himself to circumstances. Men dwell even in the very coldest regions. The place where the lowest temperatures have been measured, Verkhoyansk, with a mean January temperature of -54° F., is the capital of a Siberian province; and a district where the temperature is of the very hottest, Massowah, is the most important town in the Italian colony of Eritrea. However, both heat and cold, when excessive, tend to lessen population, the size of settlements, and economic activity. The great issues of the world’s history have been decided on ground situated between the tropic of Cancer and the Polar circle. The question as to whether the northern half of North America should be English or French was decided between the parallels of 44° and 48° north latitude; and in the same manner the settlement as to whether Sweden or Russia should be supreme in Northern Europe took place a little south of 60° north. Holland did not lose and regain her Indian possessions in the neighbourhood of the equator, but in Europe; and Spain fell from the high estate of sovereign over South and Central America because her power as a European nation had decayed. [Sidenote: Strange Divergence of a Race] The coldest countries in the world are either entirely uninhabited--as Spitzbergen and Franz Josef’s Land--or very thinly populated. Some are politically without a master--the two territories just mentioned, for example; some are politically occupied, as is Greenland, but are of very little value. History teaches that traffic between such colonies and the mother country may cease entirely without the mother country suffering any loss thereby. The hottest regions in the world are for the most part colonies or dependencies of European Powers. This applies to the whole of tropical Africa, Asia, Australia, and Oceania, and partly to tropical America. The exclusion of European nations from grasping for possessions in America was not determined upon in the compromised territory of tropical America, but in the United States, a short distance south of 39° north latitude. What a difference in the parts played in history by the two branches of the Tunguse race, the one held in subjection in the cold latitude of Russia, the other conquering China, and now the sovereign power in the more temperate climate of that country; or between the Turks who, as Yakuts, lead a nomadic life in the Lena valley, and the Turks who govern Western Asia! Latham called the region extending from the Elbe to the Amoor--within which dwell Germans, Sarmatians, Ugrian Finns, Turks, Mongolians, and Manchurians, peoples who strike with a two-edged sword--a “Zone of Conquest.” Farther to the north nations are poor and weak; toward the equator, luxurious and enervated. The inhabitants of this central zone have over-run their neighbours both to the north and to the south, while never, either from the north or from the south, have they themselves suffered any lasting injury. The Germans have advanced from the Baltic Sea to the Mediterranean; the Slavs inhabit a territory that extends from the Arctic Ocean to the Adriatic Sea; the Turks and Mongolians have penetrated as far south as India; and there have been times when Mongolians ruled from the Arctic Ocean to Southern India. Finally, the Manchurians have extended their sphere of influence over Northern Asia as far south as the tropic of Cancer. ISOTHERMAL LINES JANUARY ISOTHERMAL LINES JULY EFFECT OF CLIMATE ON THE COURSE OF HISTORY A map on which the isothermal lines are drawn is rich in historical instruction. Where the lines diverge we have regions of equal temperature; where they crowd together, districts of different mean annual temperatures lie close together. The crowding of climatic variations in any region enlivens and hastens the course of history. ] These differences occur over again in more restricted areas, even within the temperate zone itself. The inhabitants of the colder portions of a country have often shown their superiority to the men who dwell in the warmer districts. The causes of the contrast between the Northerners and the Southerners, which has dominated in the development of the United States, may for the most part be clearly traced: the South was weakened by the plantation method of cultivation, and slavery; its white population increased slowly, and shared to a lesser degree than did the Northerners in the strengthening, educating influences of agriculture and manufacturing industries. Thus after a long struggle that finally developed into a war, the North won the place of authority. [Sidenote: Sunbeams and Rainfall in History] In Italy and in France the superiority of the north over the south is partially comprehensible; and in Germany the advantages possessed by Prussia, at least in area and in sea coast, are obvious. But when in English history also the north is found to have been victorious over the south, conditions other than climatic must have been the cause. In this case elements have been present that are more deeply-rooted than in sunbeams and rainfall alone. We must call to mind the zone-like territories of early times, occupied by peoples from which the nations of to-day are descended; the boundary lines have disappeared, but the northern elements have remained in the north, and the southern elements in the south. It is well known that Aristotle adjudged political superiority and the sphere of world-empire to the Hellenes because they surpassed the courageous tribes of the north in intelligence and in mechanical instinct, and were superior to the both intelligent and skilful inhabitants of Asia in courage. “As the Hellenic race occupies a central geographical position, so does it stand between both intellectually.” The thought that this union of extreme intellectuality and power in arms on Hellenic soil could be the result of ethnical infiltration did not seem to have occurred to the philosopher. The fundamental idea of Aristotle, the aristocratic state, in which the talented Hellene alone was to rule over bondmen of various origins, who were, above all, to labour for him, could not have been possible had his views been otherwise. And yet he had clearly seen that the two talents--for war and for industry--were unequally distributed among the different Hellenic stocks, and that they were also variable according to time. [Illustration: HOW THE SAME PEOPLES DIFFER The Yakuts, who lead a nomad life in the valley of the Lena, and the Turks who govern Western Asia, are of the same stock, but the genial climate has enabled the Turks to flourish while the cold has kept the Yakuts poor. These groups represent both branches of the stock. ] Considering the influence even of slighter differences in climate, the locations of regions of similar mean annual temperature, and the distances which separate them from one another, cannot be otherwise than important. A map on which the isothermal lines are drawn is rich in historical instruction. Where the lines diverge we have regions of equal temperature; where they crowd together, districts of different mean annual temperatures lie close to one another. The crowding of climatic variations in any region enlivens and hastens the course of history in that region. If the variations occur only at long intervals, all parts of a large territory having approximately equal mean annual temperatures, then climatic contrasts, which act as a ferment, as it were, are not present to any appreciable extent, and their effects lose in intensity and are dispelled. Where are greater combinations of contrasting climatic elements to be found than in Greece and in the Alps? The joining together of the natives of rich, fruitful Zürich with the poor shepherds of the forests and mountains was of the utmost importance to the development of the Swiss Confederation. It was also a union of regions of mild and cold temperatures. The possession of Central European and Mediterranean climates, that shade into one another without any sharp line of demarcation, is a great advantage to France. If climatic differences approach one another in too great a contrast, clefts in development are likely to occur, such as the gap between the Northern and the Southern States in America, and that between North and South Queensland. If it be possible to adjust the political differences, then the union of areas of different temperatures has an invigorating effect, as shown by the history of the American Southern States since 1865. [Illustration: THE EFFECTS OF CLIMATE ON THE POWER OF PEOPLES There is a world of difference between the two branches of the Tunguse race: the one is a poor people living in cold regions and subject to Russia; the other is the ruling race of the Chinese Empire, flourishing in a temperate climate. The upper group is composed of ruling Tunguses in China and the lower group represents Tunguses subject to Russia. ] Winds blowing in a constant direction for many months at a time were of great assistance to navigation during the days of sailing vessels, which, indeed, have not yet been entirely supplanted by steamships. Before the time of steam vessels all traffic on the Indian Ocean was closely connected with the change of the monsoons; and important political expansions have followed in the track of the same winds--for example, the diffusion of the Arabs along the east coast of Africa and in Madagascar. The influence of the trade winds on the Spanish and Portuguese discoveries along the Atlantic coast of America is well known. The south-eastern trade winds have been a cause of both voluntary and involuntary emigrations of Polynesian races. It may be clearly seen from the history of Greece what advantage was obtained by the race that won the alliance of the coast of Thrace and the wind that blows south from it with constancy during the entire fair season, often eight months long. Where the wind is most variable, visiting entire countries with storms, to the great destruction of lives and property, the result is a stirring up of the survivors to exertions that cannot fail to be strengthening both to body and to mind, and of direct benefit to life in general. At the same time that the people of Holland were engaged in forcing back the ocean, they won their political liberty. In another part of the North Sea coast the Frisians receded farther and farther south, owing to the invasions of the sea and the attacks of the natives of Holstein. The tempest that scattered the armada of Philip II. was one of the most important political events of the time; and it is not to be denied that the snowstorm in Prussian Eylau, at the beginning of the battle in which Napoleon suffered his first defeat, contributed not a little to the result. [Sidenote: One of the Greatest Problems] Acclimatisation is one of the greatest of human problems. In order that a nation shall expand from one zone into another, it must be capable of adapting itself to new climates. The human race is, as a whole, one of the most adaptable of all animal species to different conditions of life; it is diffused through all zones and all altitudes up to about thirteen thousand feet above the level of the sea. But single nations are accustomed to fixed zones and portions of zones; and long residence in foreign climates leads to illness and loss of life. [Sidenote: Climate and Will-Power] In some races the individuals are of a more rigid constitution than in others, and are thus less capable of adaptation. Chinamen and Jews adapt themselves to different climates far more easily than do Germans, upon whom residence in the southern part of Spain even, and to a still greater degree in Northern Africa, is followed by injurious effects. The constant outbreaks of destructive disease before which the German troops withered away are to be counted amongst the greatest obstacles opposed to the absorption of Italy into the German Empire. During the Spanish discoveries and conquests in America in the sixteenth century, whole armies wasted away to mere handfuls. The greatest hindrances to German colonisation in Venezuela are climatic diseases. Medical science has, to be sure, pointed out such deleterious influences as may be traced to unsuitable dwelling-places, nutrition, clothing, etc.; and the losses to Europe of soldiers and officials in the tropics have been greatly reduced. But even to-day deaths, illnesses, and furloughs make up the chief items in the reports sent in from every colony in the tropics. British India can only be governed from the hills, where the officials dwell during the greater part of the year. Climatic influence is not limited to bodily diseases. One of the first effects of life in warm climates upon men accustomed to cold regions is relaxation of what is known as will-power. Even the Piedmontese soldier loses his erect carriage in a Neapolitan or Sicilian garrison. Englishmen in India count on an ability to perform only half the amount of work they would be capable of at home. Many inhabitants of northern countries escape the bodily diseases of the tropics; but scarcely one man of an entire nation is able to resist the more subtle alterations in spirit. [Sidenote: The Peoples of North and South] Their historical influence extends only the deeper for it. The conquering nations that advance from north to south have invariably forfeited their power, determination, and activity. The original character of the Aryans who descended into the lowlands of India has been lost. A foreign spirit rings through the Vedic hymns. West Goths and Vandals alike lost their nationalities in Northern Africa and Spain, as the Lombards lost theirs in Italy. In spite of all emigration, immigration, and wandering hither and thither, there always remains a certain fixed difference between the inhabitants of colder and those of warmer countries; it is the nature of the land, moulding the more ductile character of a people into its own form. There are differences also between the northern and the southern stocks of the same race, and thus climate exerts here greater and there lesser influence upon nations and their destinies. Since it lies in the nature of climatic influences to produce homogeneity among those peoples who inhabit extensive regions of similar mean annual temperatures, it follows that a unifying effect is also produced on political divisions that might otherwise be inclined to separate from one another. In the first place, a similar climate creates similar conditions of life, and thus the northern and southern races of each hemisphere, with their temperate and their hot climates, differ widely. Climate is also the cause of similar conditions of production over large territories. Leroy-Beaulieu rightly mentioned climate--above all, the winter, during which almost every year the whole land from north to south is covered with snow--as next in importance to the configuration of the country in its unifying, cohesive effects on the Russian Empire. Winters are not rare during which it is possible to journey from Astrachan to Archangel in sledges; and both the Sea of Azov and the northern part of the Caspian Sea are frozen over during the cold months, as well as the Bay of Finland, the Dnieper as well as the Dwina. [Illustration: A STORM THAT CHANGED THE COURSE OF HISTORY: THE WRECK OF THE ARMADA The weather has greatly influenced the course of history and helped to mould the fate of nations. The tempest that scattered the Spanish Armada in 1588 was one of the most important political events of the time. This picture, from the painting by J. W. Carey, illustrates the wreck of the galleon “Girona,” at Giant’s Causeway. ] Situation determines the affinities and relations of peoples and states, and is for this reason the most important of all geographical considerations. Situation is always the first thing to be investigated; it is the frame by which all other characteristics are encircled. Of what use were descriptions of the influence of the geographical configuration of Greece on Grecian history, in which the decisive point that Greece occupies a medial position between Europe and Asia, and between Europe and Africa, was not insisted upon above all? Everything else is subordinate to the fact that Greece stands upon the threshold of the Orient. However varied and rich its development may have been, it must always have been determined by conditions arising from its contiguity with the lands of Western Asia and Northern Africa. Area in particular, often over-valued, must be subordinated to location. The site may be only a point, but from this point the most powerful effects may be radiated in all directions. Who thinks of area when Jerusalem, Athens, or Gibraltar is mentioned? When it is found that the Fanning Islands or Palmyra Island is indispensable to the carrying out of England’s plans in respect to telegraphic connection of all parts of the empire with one another, merely because these islands are adapted for cable stations on the line between Queensland and Vancouver, is it not owing to their location alone, without consideration as to area, configuration, or climate? Every portion of the earth lends its own peculiar qualities to the nations and races that dwell upon it, and so does each of its subdivisions in turn. Germany, as a first-class Power, is thinkable only in Europe. There cannot be either a New York or a St. Petersburg in Africa. Our organic conception of nations and states renders it impossible for us to look upon situation as something lifeless and passive; far rather must it signify active relations of giving and receiving. Two states cannot exist side by side without influencing each other. It is much more likely that such close relationships result from their contiguity; that, for example, we must conceive of China, Korea, and Japan as divisions of a single sphere of civilisation, their history consisting in a transference, transplanting, action, and reaction, leading to results of the greatest moment. Some situations are, indeed, more independent and isolated than others; but what would be the history of England, the most isolated country in Europe, if all relations with France, Germany, the Netherlands, and Scandinavia were omitted? It would be incomprehensible. The more self-dependent a situation is, the more is it a natural location; the more dependent, the more artificial, and the more it is a part of a neighbourhood. Connection with a hemisphere or grand division, identity with a peninsula or archipelago, location with respect to oceans, seas, rivers, deserts, and mountains, determine the histories of countries. It is precisely in the natural locality that we must recognise the strongest bonds of dependence on Nature. Apart from all other features peculiar to Italy, her central position in the Mediterranean alone determines her existence as a Mediterranean Power. However highly we may value the good qualities of the German people, the best of these qualities will never reach so high a development in the constrained, wedged-in, continental situation of their native land as they would in an island nation; for Germany’s location is more that of a state in a neighbourhood of states than a natural location, and for this reason more unfavourable than that of France. _Outward Voyage of Columbus shown thus_ _Homeward Voyage of Columbus shown thus_ _Periodical Winds_ (_Monsoons_) _shown thus_ _Prevailing & Constant Winds shown thus_ POLITICAL EXPANSION HAS FOLLOWED IN THE TRACK OF THE WINDS This map illustrating the trade winds and prevailing winds shows how important were these winds before the days of steam vessels. It shows that the outward voyage of Columbus was entirely along the track of the north-east trade winds. Where the arrows cross, as off the North-west of Scotland, we have regions of wind disturbances. ] [Illustration: THE RIVERS OF TWO CONTINENTS AND THEIR INFLUENCE IN CIVILISATION The influence of riverways in furthering political development may be best seen in the contrast between South America and Africa; the colonising movement came to Africa three hundred years later than to South America. EUROPEAN COUNTRIES AND THEIR NEARNESS TO THE SEA A country’s prosperity depends greatly upon its relation to the sea. This map shows the boundaries of European countries, and the black lines indicate those countries that lie within 250 and 500 miles from the sea-coast. THE RELATION OF RIVERS AND THE SEA TO THE CIVILISATION OF COUNTRIES] [Sidenote: The Ideal Situation for a State] Natural localities of the greatest importance result from the configuration and situation of divisions of the earth’s surface. The extremities of continents--such as the Cape of Good Hope, Cape Horn, Singapore, Ceylon, Tasmania, and Key West--are points from which sea power radiates; and at the same time they are the summits of triangular territories that extend inland and are governed from the apex. In the same way all narrowings of parts of continents are of importance. France occupies an isthmian position between ocean and sea; Germany and Austria between the North Sea, the Baltic, and the Adriatic. Some states are situated on the coast, occupying a bordering position; others occupy an intermediate location. And the more isolated situations are all fundamentally different, according to whether they are insular, peninsular, or continental. Situations in respect to the oceans are even more various. How different are Atlantic locations in Europe from those on the Mediterranean, the Baltic, or the Black Sea! Only a few nations occupy a position fronting on two great oceans. The ideal natural situation for a state may be said to be the embracing of a whole continent within one political system. This is the deeper source of the Monroe Doctrine. [Sidenote: Contrasts and Comparisons] Similar locations give rise to similar political models. Since there are several types of location, it follows that the histories of such locations assume typical characters. The contrast between Rome and Carthage, their association with each other, exhibiting the reciprocal action of the characters of the northern and southern Mediterranean coasts, is repeated in similarly formed situations in Spain and Morocco, in Thrace and Asia Minor, and on a smaller scale in the Italian and Barbary ports. In all these places events similar to those in Roman and Punic history have taken place. Japan and England are unlike in many respects; yet not only the peoples, but also the political systems, of the two island nations have insular characteristics. Germany and Bornu are as different from each other as Europe is from Africa, but central location has produced the same peculiarity in each--a source of power to the strong nation, of ruin to the weak. Contiguity with neighbouring states brings with it important relationships. The most striking examples of such contiguity are to be seen in nations that are cut off from the coast of their continent and completely surrounded by other countries. Owing to the constant reaching out for more territory, such a situation in Europe, as well as in other continents, signifies unconditional loss of independence. Only connection with a great river can prevent the dissolution of a nation so situated. The instinctive impulse to extend its boundaries to the sea, shown by all nations, arises from the desire to escape an insulated continental position. Only the very smallest of states, such as Andorra and Liechtenstein--which, moreover, do not aspire to absolute independence--could have existed for centuries in the positions that they occupy. A medial situation held by one country between two others is also, in point of risk, comparable to a completely encompassed position. France was so situated when Germany and Spain were under the same ruler. The alliance of two neighbouring lands may place a third state in a similar position. [Sidenote: What is National Progress?] Whatever the individual locations of neighbouring states may be, their number is a matter of great importance. It is better to have a multitude of weak neighbours than a few strong ones. The development of the United States that gradually ousted France from the south, Mexico from the west, and Spain from both south and west, in order to be in touch with the sea on three sides, has, with the decrease in neighbouring Powers, resulted in an enviable simplification of political problems. A nation covering various dispersed and scattered situations is to be seen at the present day only in regions of active colonisation and in the interiors of federal states. Powerful nations are consolidated into a single territory. We may see everywhere that when the area of distribution of a form of life diminishes in extent, it does not simply shrink up, but transforms itself into a number of island-like sites, giving the appearance that the form, of life is proceeding from a centre of the conquest of new territory. In what does the difference lie between islands of progress and of recession? With nations and states progress lies in the occupation of the most advantageous sites; retrogression lies in their loss and sacrifice. The American Indians, forced back from oceans, rivers, and fertile regions, form detached groups of retrogression; the Europeans who took these sites from them formed isles of progress as, one after another, they seized the islands, promontories, harbours, river-mouths, and passes. [Illustration: THE MAKING OF THE NATIONS--IV Professor FREDERICK RATZEL] THE SIZE AND POWER OF NATIONS [Sidenote: The State and its Territory] It is not without reason that so much importance is attached to extent of surface in geography. Area and population represent to us the two chief characteristics of a state; and to know them is the simplest means--often too simple--for obtaining a conception of the size and power of a nation. We cannot conceive of any man, much less a human community, without thinking of surface or ground at the same time. Political science may, through a number of clever conclusions, reduce the area of a state to a mere national possession; but we all know that territory is too tightly bound up with the very life of a state for it to assume a position of so little importance. In a nation, people and soil are organically united into one, and area and population are the measure of this union. A state cannot exchange or alter its area without suffering a complete transformation itself. What wonder, then, that wars between nations are struggles for territory? Even in war the object is to limit the opponent’s sphere of action; how much more does the whole history of nations consist in a winning and losing of territory. The Poles still exist as they did in former times; but the ground upon which they dwell has ceased to belong to them in a political sense, and thus their state has been annihilated. [Sidenote: The Vast Modern Empires] During the course of history we constantly see great political areas emerging from the struggle for territory. We see nations from early times to the present day increasing in area: the Persian and Roman Empires were small and mean compared with those of the Russians, English, and Chinese. Also the states of peoples of a lower grade of culture are insignificant compared with the states of more advanced races. The greatest empires of the present day are the youngest; the smallest--Andorra, Liechtenstein, San Marino, Monaco, appear to us only as venerable, strange petrifications of an alien time. The relation of surface to the growth of spheres of commerce and of means of communication is obvious. Communication is a struggle with area; and the result of this struggle is the overcoming of the latter. The process is complicated because, as control is gained over area, one also acquires possession of its contents: advantages of location, conformation, fertility, and, by no means least, the inhabitants of the territory themselves. But the loss in value of all these things, brought about by their being widely scattered throughout an extensive area, can be overcome only by a complete control of the region over which they are spread. [Sidenote: Traffic Leads to Empire] The development of commerce is the preliminary history of political growth. This applies to all races, from Phœnicians to North Americans, who point out to us a post of the American Fur Company as the germ from which Nebraska developed. Every colony is a result of traffic; even in the case of Siberia, merchants from European Russia travelled thither as far as the Ob about three centuries before its conquest. The phrase “conquests of the world’s commerce” is perfectly legitimate. The building of roads is a part of the glory of the founders and rulers of nations. To-day, tariff unions and railway politics have taken the place of road-making. It has always been so; both state and traffic have had the same interest in roads and thoroughfares. Traffic breaks the way, and the state improves and completes it. It seems to be certain that the firmly organised state in ancient Peru opened the roads which were later a service to traffic. In a lower phase of development we may see commerce leading directly to the establishment of states; in a higher, to victory in war, arising from commercial and railway communication. It would be impossible for France to construct the Sahara Railway without first subjugating the Tuareg and seizing their country. Highways of traffic as weapons for hostile states, the important part played by commercial nations and the culture of strictly industrial and commercial peoples, the endeavour of traffic to be of service to the policies of states, and, finally, the powerful reactions caused by the removal and disuse of thoroughfares of commerce to races, nations, and to entire spheres of civilisation--can only be indicated here. [Sidenote: Every Trader Bears his State with him] Every political movement, whether it be a warlike expedition or a peaceful emigration, is preceded by movements which are not political. Inquiries must be made and relations instituted; the object must be determined, and the road explored. All the while that knowledge of the world beyond the bounds of a country is being gained, there is also an imperceptible broadening of the geographical horizon; and this not only widens out, but becomes clearer. Fabulous tales are circulated as to the terrors of strange countries; but the fear gradually vanishes as our knowledge increases, and with the latter a spirit of political enterprise awakens One can say that every trader who passes the bounds of his country bears his state with him in his load of merchandise. To be sure, there are both long preparations made and quick leaps taken in the processes of commerce. Roman merchants prepared the way to a knowledge of Gaul and its conquest. But how different the attitude of the Romans to Gaul before and after the time of Cæsar! What a difference in the Spanish estimate of the worth of American colonies before the days of Cortez and Pizarro, and afterward! The broader and clearer the geographical horizon grows, the greater become political schemes and standards of policy. [Sidenote: Causes of National Success and Failure] The widening of the geographical horizon and the clearing up of mysteries beyond are invariably a result of the travels of individuals or of groups for peaceful purposes. The first of these purposes is commerce; the chase and fishing are also to be taken into consideration; and the involuntary wanderings of the lost and strayed are not to be excluded. Europe possessed a Pytheas and a Columbus who discovered new worlds; and every primitive community had its explorers, too, who cleared paths from one forest glade to another. If such pioneers return, they also bring back with them contributions to the general stock of knowledge of the world without, and it becomes less difficult for others to follow in their footsteps; finally armies or fleets may advance, conquering in their tracks. Whenever traffic makes busy a multitude of men, and employs extensive means by which to carry on its operations, the truth of the saying, “The flag follows trade,” is finally established in its broadest sense. With all this struggling and labouring, territory does not fall to the state simply as a definite number of square miles. Just as single individuals bring enlightenment to the state, in the same manner the idea of area arises in the intelligence of the aggregate. When we say that an area increases, we must remember that by this we mean that the intelligence which views it and the will that holds it together have increased, and naturally, also, that which is requisite for rendering intelligence and will capable for their work. In this lies one of the greatest differences that exist between nations, one of the greatest causes of success and failure in development. A disposition for expansion that advances boundaries to the farthest possible limit is a sign of the highest state of civilisation. It is a result of an increase both of population and of intellectual progress. [Sidenote: Small States in Fine Situations] There is something very attractive in the small political models of early times: those city-states whose development had in definiteness and in precision a great deal of the lucidity and compactness of artistic compositions. Lübeck and Venice are more attractive than Russia. The concentration of the forces of a small community in a limited, beautifully situated, and protected location, is a source of a development that takes a deeper hold on all the vital powers of a people, employing them more extensively, and therefore ending in a more rapid and definite perfection of historical individuality. Thus small areas take the lead of large territories in historical development; and we may see many examples of a slow but sure transference of leadership from the small area to the large, and of the gradual diffusion of progress in the latter. Thus Italy followed Greece; Spain, Portugal; England, Holland. [Illustration: THE COMMAND OF THE SEAS: GREAT BRITAIN’S MIGHTY MACHINERY OF DEFENCE Great Britain’s strength is a proof of the tremendous importance of the sea as a factor of political power. This is a bird’s-eye view of the British Navy assembled at Spithead. ] The opposite of this is precocity in growth: the earlier a state marks out its limits without consideration for later expansion, the sooner the completion of its development. The growth in area of Venice and the Low Countries stood still, while all about them territories increased in size. The development of small countries flags unless the increase of population within a limited area leads to that disquiet and emigration and expulsion of citizens especially characteristic of small nations: the horizon grows too narrow for the times; patriotism becomes local pride; and the most important life forces are impaired. Thus minor nations, through which races are separated into little groups, develop: the great national economic and religious cohesive forces are broken up; and even the political advantages of the ground are reduced in value through disintegration. [Sidenote: Founding of States by Strangers] Under such conditions the impulse for new growth must be brought in from without. The native, who is acquainted with only one home, is always inferior to the foreigner, who has a knowledge of two lands at least. It is remarkable how numerous are the traditions of the establishment of states by strangers. Sometimes these are mighty hunters, as in Africa; often they are superior bearers of civilisation, as in Peru; and an especially large number of them have descended to the earth from heaven. In the face of history which tells of the foundation of a Manchurian dynasty in China and a Turkish in Persia, of the establishment of the Russian Empire by wandering North Germans, and that of the great nations in the West Sudan by the Fulah shepherds--these mythical accounts, although they may appear decidedly incredible when taken singly, as a whole are probable enough. The foundation of the nation of Sarawak in Borneo by Brooke is reality and corresponds with many of the old legends of the formations of states. [Sidenote: A Great Turning-point in History] The broad conception of a state, which acts as a ferment does on a disrupted mass, is introduced from one neighbouring nation into another, each sharing in its production. When such territories are adjacent, the state situated in the most powerful natural region overgrows the other. The more mobile race brings its influence to bear on the less mobile, and possibly draws the other along with it. The more compact, better organised and armed state intrudes on weaker nations, and forces its organisation upon them. A nation left to itself has a tendency to split up into small groups, each of which seeks to support its own life upon its own soil, heedless of the others; and as such groups increase, they always reproduce in their own images: families families, and tribes tribes. We find all sorts of measures taken by some nations to limit an increase in growth that would carry them beyond their old boundaries and place them under new conditions of life. Many an otherwise inexplicable custom of taking human life is a result of this tendency; perhaps, in some cases, even cannibalism itself. This impulse towards limitation would have rendered the growth of nations impossible had not the antithetical force of attraction of one to another led to growth and amalgamation. Truly, the advance from a condition of isolated, self-dependent communities to one of traffic between state organisms, which must of necessity lead to ebb and flow and union of one group with another, is one of the greatest turning-points in the history of man. [Sidenote: Nations as Neighbours] Since the tendency has been for territory to become the exclusive reward of victory in the competition of nations, balance of territorial possessions has grown to be one of the chief ends of national policies. The phrase “balance of power,” which has been so often heard since the sixteenth century, is no invention of diplomats, but a necessary result of the struggle for expansion. Hence we find an active principle of territorial adjustment and balance in all matters concerning international politics. It is not yet active in the small and simple states of semi-civilised peoples; such states are much more uniform, for they have all originated with a uniformly weak capacity for controlling territory. In addition, the principle of territorial isolation hinders the action of political competition. As soon, however, as necessity for increased area leads to the contiguity of nations, the conditions alter. The state that occupies but a small region strives to emulate its larger neighbour. It either gains so much land as is necessary to restore equality, or forces a decrease in the neighbour’s territory. [Sidenote: The Balance of Power] Both alternatives have been of frequent occurrence. Prussia expanded at the expense of Schleswig and Poland in order to become equal in territory to the other great Powers. The whole of Europe fought Napoleon until France had been forced back within such boundaries as were necessary to international balance. Austria lost provinces in Italy and replaced them with others in the Balkan Peninsula. This loss and gain appears to us, in looking over an easily epitomised history, such as that of France, as an alternation of violent waves and temporary periods of rest attained whenever a balance is reached. Therefore it is not owing to chance that the areas of Austria, Germany, France, and Spain may be respectively designated by 100, 86, 84, and 80, that the area of Holland is to that of Belgium as 100 is to 90, and that the United States stands to Canada as 100 to 96. To be effective, such balances must presuppose equal civilisations, similar means for the acquirement of power. Rome was so superior to her neighbours in civilisation that she could not permit any territorial balance. Perhaps the adoption of the River Halys as the boundary between Media and Lydia was a first attempt to establish a national system on the principle of balance instead of “world” dominion. [Sidenote: A New British Empire is not Conceivable] Our standards for measuring the areas of countries have constantly increased during the growth of historical territories. The history of Greece is to us but the history of a small state; and how many years shall pass before that of Germany, Austria, and France will be but the history of nations of medium size? England, Russia, China, and the United States include the better half of the land of the world; and to-day a British Empire in the other half could not be conceivable. Development has ever seized on greater and greater areas, and has united more and more extensive regions into aggregates. Thus it has always remained an organic movement. The village-state repeats itself in the city-state, and the family-state in the race-state, the smaller ever being reproduced in greater forms. The smallest and greatest nations alike retain the same organic characteristics more or less closely united to the soil. [Sidenote: Area Does Not Mean Power] The surface of a state bears a certain relation to the surface of the globe, and according to this standard is the land measured upon which the inhabitants of a nation live, move, and labour. Thus it may be said that the 208,687 square miles of the German Empire represent about 1/940 of the entire surface of the earth; further, that the empire has a population of 60,500,000, from which the ratio of 5·45 acres to each individual follows. Although it is true that wholly uninhabited or very thinly populated regions, high mountains, forests, deserts, etc., may be valuable from a political point of view, nevertheless the whole course of the world’s history shows us that, as a general rule, the value of territory increases with the number of inhabitants that dwell upon it. Thus, before their disunion, Norway-Sweden, with an area of 297,000 square miles--two-fifths greater than that of the German Empire--but with a population of 6,800,000, cannot be looked upon as a first-class Power; while Germany closely approaches the Russian Empire in strength, for although its area is but 1/43 that of the latter, its population is only one-half less. Thus area alone is never the deciding factor of political power. In the non-recognition of this fact lies the source of the greatest errors which have been made by conquerors and statesmen. The powerful influence that small states, such as Athens, Palestine, and Venice, have exerted on the history of the world proves that a great expanse of territory is by no means indispensable to great historical actions. The unequal distribution of mankind over a definite area is a much more probable source of political and economic progress. Civilisation and political superiority have always attended the thickly populated districts. Thus the whole of development has been a progression from small populations dwelling in extensive regions to large populations concentrated in more limited areas. Progress first awoke when division of labour began to organise and differentiate among heaped-up aggregates, and to create discrepancies promoting life and development. A simple increase of bodies and souls only strengthens that which is already in existence by augmenting the mass. In China, India, and Egypt, population has increased for a long time; but development of civilisation and of political power has been unable to keep pace with it. [Illustration: THE MAKING OF THE NATIONS--V Professor FREDERICK RATZEL] THE FUTURE HISTORY OF MAN [Sidenote: Man and the Universe] Looking back upon the history of man, it appears to us the history of the human race as a life phenomenon bound and confined to this planet alone. We are thus unable to form any conception of progress into the infinite, for every tellurian life-development is dependent upon the earth, and must always return to it again. New life must follow old roads. Cosmic influences may broaden or narrow the districts within which man is able to exist. This was experienced by the human race during the Glacial Period, when the ice sheet first drove men toward the equator, and later, receding, enabled them once more to spread out to the north. The limits of world life in general depend upon earthly influences; and thus, for mankind, progress limited by both time and space is alone possible. Perhaps it would be well, for the elucidation of the question of development, were geography to designate as progress only that which from sufficient data may be established as such beyond all doubt. Thus, to begin with, we have learned to know of a progress in space--man’s diffusion over the earth--which proceeds in two directions. The expansion of the human race signifies not only an extension of the boundaries of inhabited land far into the Polar regions, but also the growth of an intellectual conception of the whole world. [Sidenote: Manifold Growth of Mankind] Together with this progress there have been countless expansions of economic and political horizons, of commercial routes, of the territories of races and of nations--an extraordinarily manifold growth that is continually advancing. Increase of population and of the nearness of approach of peoples to one another goes hand in hand with progressing space. Mankind cannot become diffused uniformly over new areas without becoming more and more familiar with the old. New qualities of the soil and new treasures have been discovered, and thus the human race has constantly been made richer. While these gifts enriched both intellect and will, new possibilities were all the while arising, enabling men to dwell together in communities; the population of the earth increased, and the densely inhabited regions, at first but small, constantly grew larger and larger. [Sidenote: History is the Growth of Differences] With this increase in number, latent abilities came to life; races approached one another; competition was entered into; interpenetration and mingling of peoples followed. Some races acted mutually in powerfully developing one another’s characteristics; others receded and were lost, unless the earth offered them a possibility of diffusion over better protected regions. Already we see in these struggles the fundamental motive of the battle for area; and at the same time, on surveying this progress, we may also see the limit set to it--that increase in population is unfavourable to the progress of civilisation in any definite area, if the number of inhabitants become disproportionately large in respect to the territory occupied. Many regions are already over-populated; and the numbers of mankind will always be restricted by the limits of the habitable world. Already in the differences in population of different regions lie motives for the internal progress of man; but yet more powerful are those incentives to the development of internal differences in races furnished by the earth itself through the manifoldness of its conformation. The entire history of the world has thus become an uninterrupted process of differentiation. At first arose the difference between habitable and uninhabitable regions, and then within the habitable areas occurs the action brought about by variations in zones, divisions of land, seas, mountains, plains, steppes, deserts, forests--the whole vast multitude of formations, taken both separately and in combination. Through these influences arise the differences which must at first develop to a certain extent in isolation before it is possible for them to act upon one another, and to alter, either favourably or unfavourably, the original characteristics of men. [Sidenote: Earth’s Variety Reflected in its Peoples] All the variations in race and in civilisation shown by different peoples of the world, and the differences in power shown by states, may be traced to the ultimate processes of differentiation occasioned by variations in situation, climate, and soil, and to which the constantly increasing mingling of races, that becomes more and more complex with the diffusion of mankind over the globe, has also contributed. The birth of Roman daughter states, and the rise of Hispano-Americans and Lusitano-Americans from some of these very daughter nations, are evidences of a development that ever strives for separation, for diffusion over space, which may be compared only to the trunk of a tree developing, and putting forth branches and twigs. But the bole that has sent forth so many branches and twigs was certainly a twig itself at one time; and thus the process of differentiation is repeated over and over again. Progress in respect to population and to occupied area is undoubted; but can these daughter nations be compared to Rome in other respects? They have shown great powers of assimilation and great tenacity, for they have held their ground. Nevertheless, their greatest achievement has been to have clung fast to the earth; in other words, to have persisted. Certainly this is far more important than the internal progress in which the branches might perhaps have been able to surpass the older nation. [Sidenote: Decisive Element in a Nation] It is an important principle that since all life is and must be closely attached to the soil, no superiority may exist permanently unless it be able to obtain and to maintain ground. In the long run, the decisive element of every historical force is its relation to the land. Thus great forces may be seen to weaken in the course of a long struggle with lesser forces whose sole advantage consists in their being more firmly rooted in the soil. The warlike, progressive, on-marching Mongols and Manchus conquered China, it is true, but they have been absorbed into the dense native population and have assumed the native customs. The same illustration applies to the founding of nations by all nomadic races, especially in the case of the Southern European German states that arose at the time of the migration of Germanic peoples. The health and promise of the English Colonies in Australia present a striking contrast to the gloom that reigns over India, of which the significance lies only in a weary governing, conserving, and exploiting of three hundred millions of human beings. In Australia the soil is acquired; in India only the people have been conquered. Will a time ever come when all fertile lands will be as densely populated as India and China? Then the most civilised, evolved nation will have no more space in which to develop, maintain, and root its better characteristics; and the success of a state will not result from the possession of active forces, but from vegetative endowments--freedom from wants, longevity, and fertility. [Sidenote: The Goal of the Nations] Even though the future may bring with it a union of all nations in the world into the one great community already spoken of in the Gospel of John, growth may take place only through differentiation. And thus there is no necessity for our sharing the fear that a world-state would swallow up all national and racial differences, and all variations in civilisation. From the fact that history is movement, it follows that the geographer must recognise the necessity for progress in space in the sense of a widening out of the historical ground, and a progressive increase of the population of this ground; further, a development toward the goal of higher forms of life together with an uninterrupted struggle for space between the older and newer life-forms. Yet, for all this, the definite bounds set to the scene of life by the limited area of our planet always remain. Finally, all development on earth is dependent on the universe, of which our world is but a grain of sand, and to the time of which what we call universal history is but a moment. There must be other connections, definite roads upon which to travel, and distant goals, far beyond. We surmise an eternal law of all things; but in order to _know_, we should need to be God himself. To us only the belief in it is given. FREDERICK RATZEL [Illustration: THE FAR EAST DIVISION OF THE HISTORY OF THE WORLD This History begins with the East and comes westward round the world. Japan is therefore the first country to come into its survey, and from Japan we travel to Siberia, which, though extending far west, must be treated as one. After Siberia come China and Korea; and Australia, Oceania, and Malaysia all come into the “Far East” when thus treated geographically. The whole of the white portion of this map is treated in the Grand Division which now opens. ] [Illustration: HISTORY OF THE WORLD SECOND GRAND DIVISION THE FAR EAST STEPHEN REID ] SECOND GRAND DIVISION THE FAR EAST The Far East falls into two sections, Asiatic and Oceanic. The Asiatic comprises the insular empire of Japan; and, on the continent, China, Korea, and Siberia, the extreme northern territory which, though extending far westward, must be treated as one. The Oceanic division includes the Australian continent, with the island of Tasmania; the Pacific islands grouped under the names of Melanesia, Micronesia, and Polynesia, to which last New Zealand is attached, the whole being conveniently associated under the name of Oceania; and the Malay Archipelago, or Malaysia, lying between Australia and the Asiatic continent. Of these three sections of Oceanic Far East only Malaysia has a record extending over centuries. The history of the other two, till the white sea-going races began to settle among them, is inferential, conjectural. A doubt was suggested whether New Zealand should be attached rather to Australia than to Oceania, for the reason that it has developed into one of the group of autonomous states which make up so large a portion of the British Empire; but this consideration must clearly yield to those based on geography and ethnology. PLAN THE INTEREST & IMPORTANCE OF THE FAR EAST Angus Hamilton JAPAN Arthur Diósy and Max von Brandt SIBERIA Dr. E. J. Dillon and other writers CHINA Sir Robert K. Douglas, W. R. Carles, C.M.G., and other writers KOREA Angus Hamilton AUSTRALIA & OCEANIA Hon. Bernhard R. Wise and Professor Weule MALAYSIA Basil Thomson and other writers INFLUENCE OF THE PACIFIC OCEAN IN HISTORY For full contents and page numbers see Index [Illustration: LANDS & PEOPLES OF THE FAR EAST] THE INTEREST AND IMPORTANCE OF THE FAR EAST BY ANGUS HAMILTON The influence of environment upon a people is seldom shown more prominently than in the high degree of civilisation attained by the early Chinese. Although the records are shrouded in mystery and marred by discrepancies, a consensus of scientific opinion traces the origin of the Chinese to a nomad tribe who, setting out from the shores of the Caspian, continued to wander until it found a home on the banks of the Yellow River and in the plains of Shansi. Under the influence of these immigrants, the rude manners of the aboriginals gave way to conditions in which a knowledge of the smelting of iron and the resources of agriculture was acquired. In the upward process of development, the weaving of flax into garments and the spinning of silk from cocoons followed; then, with primeval chaos reduced to order and the faculties quickened by habits of industry, the beginnings of government were made in the separation of the tribes from one another under their own leaders. While conditions of a settled existence were in course of attainment within the region which is now known as China Proper, the spectacle of a prosperous civilisation, reacting upon the uncouth instincts of tribes dwelling among the grassy uplands of Mongolia and the plains of Manchuria or amid the ice-clad fastnesses of the mountains and forest-strewn valleys of the farthest north, was presently to be responsible for the rise of predatory races, who, in the zenith of their strength, regarded the teeming cities of the south as lawful prizes. While the northern heights of Asia were producing a race that was to leave an indelible impression on the whole of the Asiatic Continent, the evolution of a no less specific type was proceeding in the islands off the coast. Carried by a wave of migration from India, which lapped the coast of Malaysia, Indo-China and Polynesia, and mingled in the islands of the Yellow Sea with a stream from New Guinea so that separate ethnographic identities were lost, were tribes who looked to the ocean for their existence much as the earlier Chinese relied upon the proceeds of their husbandry and the northern nomads upon their flocks. Glancing at the people living amid the plains, the uplands, and the islands, it will be seen that an irresistible force was enveloping the several races, moulding their instincts and idiosyncrasies in accord with the nature of their environment. Thus, while the Chinese, under the incentive of a knowledge of arts and crafts, had already produced, in 2356 B.C., a system of civilisation destined to endure to our time, the nomads and the islanders, unqualified by knowledge and controlled by climate, were hardly removed from a state of savagery a few centuries before the Christian era. If the passage of 4,000 years has affected the Chinese no more than the gliding of an hour, the existence of this great impassive people has not been without its effect upon the nations of Europe as upon the races of the Farthest East. [Sidenote: Eternal Mystery of China] A point of ancient contact between Christendom and the world of Confucius, reflecting, in contemporary Japan to-day the more permanent qualities of its teaching, China has stirred the spirits of the adventurous in all ages by its singular graces of refinement, its hidden wealth and the exquisiteness of its artistic perceptions. Arousing the curiosity of the Arab traders as early as the eighth century, it was known to the ancients, if they journeyed by the Southern Sea, as the kingdom of Sin, Chin, Sinæ, or China, in corruption, perhaps, of the word Tzin--under which dynasty occurred, in 250 B.C., the fusion of several petty kingdoms into an organic empire; or by the name of Seres if, traversing the longitude of Asia, they came by the overland route. Known to the Middle Ages by the name of Cathay--corrupted from Kitai, the name by which China is still described by Russia and by the races of Central Asia, but which itself sprang from the Khitans, the first of the northern dynasties--it represented to European commerce of the thirteenth century the embodiment of wealth, romance, and mystery; much as its position, maintained unchanged through long centuries, had made it the actual repository of the records of Central, as well as Southern, Asia. [Sidenote: Korea, the Middle Kingdom] Contemporary with the early Egyptians, the Assyrians, and the Hebrews, and comprising an empire that in 241 B.C. represented as nearly as possible the present limits of the Eighteen Provinces, the Middle Kingdom has been affected by the great upheavals of the Western world as little as she herself has troubled to impress her methods and manner of government upon the aboriginal races beyond her borders. Indeed, filled with a lofty disdain of the outer barbarians, it was not until the chance migration to Korea of some five thousand Chinese under Ki-tze, in 1122 B.C., that the ethical, social, and political systems in vogue in China were carried further afield. Once transplanted, however, the aboriginal life of the cave-dwellers of the peninsula gave way before the superior culture of Ki-tze’s followers, and within the course of the succeeding thousand years a cluster of independent states, fashioned upon the parental model, was firmly established. Although in the centuries just before the Christian era there was a constant interchange of communications with these states of the Eastern Peninsula, the classic conservatism of the Middle Kingdom was unabated by any expression of curiosity or interest in the welfare of the unknown islands. Yet the islanders, confronted with a struggle for existence, had risked the perils of many voyages to the neighbouring coasts, spreading wonderful stories of their own land and returning with ample evidences of the power and importance of the Korean kingdom. Unconscious of this intercourse, but by reason of it, China, the tutor of Korea, became through the agency of her pupil a determining factor in the upward progression of the islanders when, between 290 B.C. and 215 B.C., in consequence of dynastic difficulties, a steady stream of inhabitants from the peninsula passed from the Land of Morning Radiance eastwards with the intention of settling on the coasts of Japan, with whose inhabitants, in fact, they at once merged. [Sidenote: Japan at the Dawn of Our Era] Though at the other end of the pole of human endeavour in comparison with the Chinese, and familiar only with the elemental accessories to life, the islanders, under the influence of this alien strain, at the dawn of our era had emerged from a state of tribal control to the recognition of the authority of a single and supreme ruler. Two centuries later Japanese arms were strong enough to invade Korea, where several victories were gained; but even then the Middle Kingdom maintained no communication with the islands of the Yellow Sea, and was more or less indifferent to the rise of over-sea relations between her vassal and the mariners from the East. It is possible to trace to this obliquity in the political vision of the Celestial Empire of the day much of the subsequent havoc that the self-same race were to inflict upon the coasts of Asia. Impressed with no consideration for the interests of the mainland, and troubled by no sense of material responsibility, Japanese corsairs harried the Chinese and Korean coasts unmercifully, finding in the occupation an outlet for that primitive but inherited instinct for aggression that stimulates the race to-day. Disturbed less by the appearance of an island Power than by a confederacy of barbarian clans that, by 1000 A.D., had exerted a mastery over Mongolia, Tartary, and Manchuria, and a century later served as a menace to the safety of the dynasty itself, the Celestial Empire was beset on two sides by enemies who were attracted by the prosperity of its people. Unmindful to a great degree of the dangers which were accumulating, an instinct for and an interest in trade, confirmed by the revelation of the self-supporting character of an empire that reached to Cochin-China in one direction and the Pamirs in another, prompted the Chinese to neglect the arts of war in their preference for the triumphs of peace. [Sidenote: The Peaceful Path of the Chinese] Characterised by a capacity for infinite pains, and possessed of a complete understanding of the varied resources of agriculture, the Chinese insensibly pursued a path leading always in a contrary direction to those marked out by Nature for the islanders, as for the fierce nomads of the steppe. Thus innately addicted to habits of peace, centuries upon centuries of undisturbed prosperity chastened natures that were never very warlike; whereas the exact inversion of this existence propelled those hordes of Tartars, Huns, Turks, Khitans, Kins, Mongols, and Manchus to leave the Far North in a disfiguring passage through Asia, and bade the islanders release their sails in expeditions against Korea. It was not enough for the founder of the Tzin dynasty to fortify his northern frontiers by the construction of the Great Wall, or for that great warrior Panchow to drive the Huns before him to the Oxus itself, or for the rulers in the long period of disunion which unites the fall of the Han dynasty to the rise of the Sung to compromise with the leaders of successive rushes of barbarian horsemen by matrimonial alliances with their families. The cause lay in the foundations of the race itself. Yet, such was the insidious character of the land against which these mounted hordes so often flung themselves that, although the imminence of attack ultimately became a thing with which the Government of China was wont to conjure the peaceful, well-contented lower classes and the luxury-loving upper classes, the effect of each invasion was dissipated so soon as the invaders experienced the subtle blandishments of Chinese civilisation. [Sidenote: Swift-moving History in Little Known Lands] Presented with remarkable clearness, we have an array of devastating invasions, the one following the other in rapid succession and occasionally assuming such dimensions that the operations riveted the attention of Europe upon the little-known lands of Asia, which in most instances required only the passage of a few centuries for the minutest vestige to be obliterated. Thus the Kins, who left no trace, displaced the Khitans, equally irrecoverable, and were in turn dispossessed by the Mongols, whose wide dominion embraced so much of the earth’s surface that in 1227 A.D. the whole of High Asia, from the Caspian to Korea, and from the Indus to the Yellow Sea, recognised its sway--always excepting the strong but still despised sea-state of Japan, whose lusty inhabitants threw back the allied hosts of China, Korea, and the Mongol monarch in 1274 and 1281. Yet if the Mongols, in an effort to wreak their vengeance on the Chinese, razed to the ground the cities of the vanquished so that their horsemen could ride over their deserted sites without stumbling, none the less they earned the acclamations of posterity by the facilities that the Mongol domination of Central Asia offered to communications between the West and Cathay. Marco Polo was not alone in his knowledge of the Court of the Great Khan, although doubtless he was the first to visit it. But this liberty of intercourse, existing only by the land route to Asia, was measured solely by the duration of the Mongol rule; freedom of action along the high-road from West to East stopped prematurely when the sway of Islam settled once again over Central Asia. Two centuries elapsed before, under the banners of the Manchus, bold horsemen of the North, in 1644, flashed once again through the plains of China, imposing, by a change of costume and of coiffure, perhaps the most striking effect of any that has followed in the train of these invasions. [Sidenote: Opening the Gates of the East] [Sidenote: Lifting the Veil in Japan] But if the exclusiveness of the Mohammedan conquerors closed the route to Cathay so effectually that for two hundred years nothing more was heard of the country, Columbus, Cabot and others set themselves the task of opening up communications by water. But it was not Cathay that they reached. That was left to the Portuguese Raphael Perestralo to accomplish by sailing, in 1511, from Malacca to Canton, and thus winning the coveted distinction of first approaching China by sea. Fifty years later (1560) the same race succeeded in obtaining a settlement at Macao, while the Spaniards gazed with longing eyes from their strongholds in the Philippine Islands upon the rich junks on the China seas. Such was the effect of these trading visits from the West that the Chinese in their turn were emboldened to visit for themselves these outlying centres of Western traffic. But it was more usually vessels from Japan that were seen, for the Chinese were still without any special appetite for Western trade. With the islanders, on the other hand, a love of barter, acting on the native instincts of a maritime people, caused them to traverse these more distant waters; although occasionally the scantiness of the resources in their own country moved them, so that they were propelled as much by stern necessity as by the lust of war and loot or a passion for trade. At first Polynesia, then Malaysia and India were visited. Again, trips were made to the remote coasts of Mexico. Still later, a colony founded at Goa became the centre of an important trading connection throughout the Indian hemisphere. In these voyages we see the attractive influence exercised by the Pacific and the Indian Oceans on an island people, who, fitted by temperament no less than by position, played in Eastern waters the rôle filled by the Elizabethan explorers on the coasts of the New World. [Sidenote: Raising the Curtain] As yet the distinctive call of the East had been heard only along the byways of Turkestan, and even those who had responded had ventured no further than the provinces of Cathay. Thus the isles of the Yellow Sea were to the Western mariner at the dawn of the sixteenth century as much a terra incognita as the Arctic and Antarctic regions are to the sailor of to-day. The spectacle of Japanese junks sailing gaily across the heaving waters of the Spanish Main and rounding the heel of India aroused the interest of the Western traders, who at once embarked for the fortunate lands of the East, arranging relations there even before they had been welcomed by the Chinese. With the arrival of Portuguese traders off Japan in 1542, a curtain was raised which was never quite to descend. In the interval a commercial entrepôt was established on the island of Hirado, and an intercourse set afoot that encouraged a visit from a Spanish squadron towards the close of the sixteenth century. This visit was returned in 1602 by the despatch of a ceremonial embassy to the Governor-General of the Philippines. [Sidenote: Untold Wealth of Asia] Throughout the first half of that century Japan continued to attract the adventurous, and the Dutch now followed in the wake of the Portuguese and Spanish ships. The reception of the bold spirits was unequal, and in 1624 all foreigners except the Dutch and the English were banished. By 1641 no traders were allowed but Dutch, who, in spite of being restricted to the island of Deshima, enjoyed a monopoly of the trade with Japan until 1867. In the meantime, abroad, rumours of the untold wealth of Asia had brought the Indies, together with Cathay and Japan, into distinct prominence. Under the Chinese Emperor Kien-Lung, whose reign of sixty years, 1735-1795, was remarkable for its conquests and successful administration, commercial intercourse with the West was regularised, and the founding of recognised trading settlements on the China coast ended the era of furtive attempts to open trade relations with this exclusive people. From these early trading stations have sprung the several commercial capitals that now grace the China coast. Hong Kong, Canton, Shanghai, Tientsin, and Newchang are the links existing to-day between the magnificence of the merchant princes and the sway of the “John Company.” Of course conditions are now much altered, yet the memories of the past find a very splendid setting in the size, dignity, and importance of the modern treaty ports. Although the Far East was already manifesting its powers of holding the attention of the civilised world, the centres of interest there were concerned for many years solely with the kingdoms of China and Japan. [Illustration: CALM IN THE FAR EAST: THE SETTING OF THE SUN IN THE MONGOLIAN DESERT] [Sidenote: China on the Western Horizon] Australasia was a great unknown when the high latitudes of Asia were the fount of many conquering races. Obviously, therefore, the magnet of acquisitiveness pointed to the value of investigating the bleak northern steppes. Once started, the Pacific and the Amur were reached within eighty years under the impetus of an unrelenting progress which swept from west to east across the regions of North Asia. Begun at the instigation of Stroganoff, who pushed the hesitating footsteps of Yermak across the Urals in 1580, by 1584 this gallant freebooter was offering to Ivan IV. with no uncertain voice the wide dominions of Siberia as the price of pardon. Khan after khan was unseated, tribe after tribe dispossessed, for neither Tartar nor Turk, Buriat nor Tunguse, could offer effective resistance to the Cossacks from the Don. In the end this all-conquering advance was stayed by the Chinese, who, in the treaty of Nertchinsk, 1689, contracted their first formal convention with a foreign Power. For nearly two centuries Russia faithfully observed the terms of this engagement, apprehensive of endangering the Kiachta trade if she continued her encroachments upon Manchu territory. By this action the trade of China, which has now made the problem of the Far East of dominating importance, became of more than passing interest to a Western Government. As generations passed, however, the advance of Russia, to the Pacific in one direction, and in search of a warm-water harbour in another, was resumed. First Eastern Siberia and then Northern Manchuria were added to her Asiatic satrapy, and the Amur ceased to be the containing line. Ultimately her frontier rested on the ocean to the north, the east, and the south; Vladivostock, Port Arthur, Harbin, and Mukden becoming the centres from which her Far Eastern dominions were administered. [Sidenote: The English Find Australia] The spirit of adventure, now inspiring all ranks of society as well as most of the civilised races of the world, was by no means satisfied by territorial conquest. The wide dominions of the sea, as yet untraced and all unknown, embraced an empire which appealed as strikingly to the sympathies of geographers as did the prospects of Far Eastern trade to the feelings of the East India merchants. Much the same ceaseless quest carried the Cossack Dejneff, in 1648, round the north-eastern extremity of Asia; Torres, a Spaniard commissioned by the Spanish Government of Peru, in 1606 negotiated the strait between New Guinea and the mainland; and various Dutch expeditions in 1606, 1616, 1618, 1627 and 1642 endured the dangers of the reef-bound coasts. But it was not until 1688 that the English first made their appearance on the Australian coast. In some measure the situation was awaiting the man. The voyages of Captain Cook (1769-1777) took up the work of geographical exploration in the Southern Hemisphere in a style quite befitting the records already elsewhere accomplished. [Sidenote: Pacific and the Destinies of Peoples] If between the continent of Australia and the coasts of China to-day there is only a commercial connection, it must not be forgotten that Australia is closely identified with the Polynesian races, who in turn are related to the early Japanese. New Zealand, Australia, New Caledonia, and New Guinea, as parts of one and the same continent, which now in many places has disappeared beneath the sea, present an ethnographic study of unusual importance and interest. In few other parts of the world is so great an ethnographic variation imposed upon a single connecting racial family as in the island divisions of the South Seas--Australasia, Polynesia, Micronesia, and Melanesia. It is by the existence of this underlying relationship that the Indo-Pacific races, whatever their specific origin, undoubtedly link up two hemispheres which organically are widely separated. By the abruptly disintegrated character of existing racial location, however, it is possible to read the impression made by the Pacific Ocean on the history of the world. If oceanic influences are represented in other ways to-day, and tribal migrations in a body are occurrences of the past, the necessities of the age still make such heavy demands on what is, after all, the immemorial highway of mankind that the Pacific can still be said to mould the destinies of races to-day as easily as it has obliterated them in the past. [Sidenote: What will Happen To-morrow?] Turning to Asia, although the Empires of Russia in Siberia and of China have worked out their destinies independently of the Pacific, remaining unaffected by it more than all other Eastern states, the part that the Pacific has played in the development of Asia since the eighteenth century cannot go unnoticed. Japan, in particular, has profited by the readiness of communication that the ocean provides to rise above prejudices which are usually inseparable from an island people and are pre-eminently to be expected among Asiatics. In China the absence of any prominent dependence on the sea, either for food or means of transport, has produced in very sinister form an aversion against the West. None the less, under pressure from the Occident, and without regarding the example set by Japan, the Celestial Empire has permitted much commercial encroachment. Succeeding the galleons of the buccaneers have come the stately traders of the merchant princes of Europe and America, and these in turn have given place to the steamers of industrial trusts, exacting as large a tribute as the earliest marauders. While the consequences of industrial expansion among Oriental people have made the Pacific the focus of much restless energy, Japan, now as great a Power on land as formerly she was, and is, at sea, has developed an intelligence that has made her pre-eminent among the trading nations of the East. Undeterred by exertion, unmoved by expenditure, Japan has displaced the carrying trade of the Pacific by her fearless invasion of Western markets. Throughout the isles of the Southern Seas, and up and down the face of the Pacific slope, the islanders have swarmed, filling the lands of their passage with unaccustomed energy. Looking back, then, at the conditions of Asia in the eighteenth and nineteenth centuries, and comparing them with those existing to-day, it will be noticed that a wide gulf still separates Japan from China in the twentieth century as it formerly separated China from the rest of the Far East. On the one side there is China, now emerging from revolution; on the other there is Japan, voicing the regeneration of Asia with raucous tones. [Sidenote: China Thirty years Hence] Meanwhile the vast interests of the Occident in the Orient are united with either power by frequent political intercourse and a traffic which has given to the Pacific priority of place in the battle for commercial supremacy. Yet while China is commercially independent of the West, and Japan dependent upon it, all branches of foreign industry cannot but view with alarm the increasing aggressiveness of the spirit of independence now inspiring Asia at the prompting of Japan. Obviously these signs are the indication of an approaching cleavage between East and West, which, when fully attained, will bear witness to the complete severance of the shackles hitherto enthralling Asia to the interests and purposes of the West. It must not be forgotten that Japan already has achieved her complete regeneration. Thirty years hence China, no doubt, will have followed suit, when a federacy of the Far Eastern Powers may become an accomplished fact. Even at this moment such a union is possible, and its realisation would impose upon all European Governments the immediate revision of their Asiatic policies. At this time such a combination is hampered only by the unwillingness of China to accept the suggestions of Japan in anything affecting the policy of Asia, although, in spite of this objection, active reforming influences are gradually effecting important changes throughout the Chinese Empire. For the moment, therefore, Japan is content to tread alone the path she has marked out, encouraging her subjects by example to exploit Asia for the Asiatics, and to secure recognition of the doctrine of equality between the white and Asiatic races. If the full significance of this movement is not yet discernible, there is enough evidence to show that the problem will rank among the greatest that the politics of the twentieth century can disclose. Not only one part of the civilised globe will be affected by the rise of a dominant Asia, for the whole world will be confronted equally with the necessity of resisting whatever indications may appear. If it is difficult to devise an arrangement short of total exclusion that does not admit an annual influx of a large number of Japanese, Chinese, Korean, or Indian immigrants into the lands affected by this invasion, it is at least tolerably certain that if the existing flow of Asiatics across the Pacific to America and Australasia continues unabated for a further decade, the areas now menaced will be inhabited by a white minority. [Sidenote: Problem of the Century] It appears evident that the continuation of the Far East under existing conditions is doubtful, if not impossible, in view of the awakening of Asia and the visible prejudices that Western democracy entertains against the Asiatic. Yet if the clash of conflicting interests ultimately precipitates a struggle between the two great racial divisions of the world, there can be no doubt that the moral teachings of humanity will be discredited. ANGUS HAMILTON +---------------------------------------------------+ \| GREAT DATES IN THE HISTORY OF JAPAN \| +------+--------------------------------------------+ \|=B.C.=\| =To 500 A.D.= \| \| =660=\| Supposed foundation of the Japanese \| \| \| Empire by Jimmu \| \| \| \| \|=A.D.=\| \| \| =3=\| Emperor Suinin flourished. Abolition \| \| \| of the practice of burying retainers \| \| \| alive on the master’s death \| \| =59=\| Reputed Korean immigration \| \| =125=\| Legendary hero Yamato Daké \| \| \| flourished \| \| =202=\| Reputed conquests in Korea by Empress \| \| \| Jingō Kōgō \| \| =397=\| Probable introduction of Chinese \| \| \| civilisation, through Korea \| \| \| \| \| \| =500-1000= \| \| =552=\| Introduction of Buddhism \| \| =645=\| The Taikwa Laws of Kōtōku \| \| =675=\| Encouragement of Buddhism by Temmu \| \| =689=\| The Laws reduced to a written code \| \| =750=\| Development of the Samurai class \| \| =782=\| Emperor Kwammu \| \| =800=\| Fusion of Shintō with Buddhism by \| \| \| Kōbō Daishi \| \| =889=\| High offices become hereditary in the \| \| \| Fujiwara family \| \| \| \| \| \| =1000-1500= \| \|=1155=\| Wars of the Taira and Minamoto \| \| \| clans \| \|=1186=\| Victory of the Minamoto \| \|=1192=\| The Minamoto Shogunate established \| \| \| Japanese feudal system \| \|=1220=\| Supremacy of the Hōjō family \| \|=1275=\| Attempt of Kublai Khan to invade \| \| \| Japan \| \|=1281=\| Destruction of the Chinese (Mongol) \| \| \| Armada \| \|=1333=\| Ashikaga revolt and overthrow of the \| \| \| Hōjō \| \|=1337=\|Rival Mikados of the North and South \| \| \| for fifty-five years \| \| \| \| \| \| =1500-1800= \| \|=1543=\| First appearance of Europeans \| \| \| (Portuguese) in Japan \| \|=1549=\| Francis Xavier attempts to introduce \| \| \| Christianity \| \|=1574=\| Overthrow of Ashikaga by Nobunaga \| \|=1581=\| Rapid development of Christianity \| \|=1582=\| Death of Nobunaga. Supremacy of his \| \| \| general Hideyoshi (Taikō Sama) \| \|=1583=\| Envoys sent from feudal lords to the \| \| \| Pope \| \|=1592=\| Hideyoshi’s invasion of Korea \| \|=1598=\| Death of Hideyoshi. Accession to \| \| \| power of Iyeyasu \| \|=1606=\| Prohibition of Christianity \| \|=1615=\| Restoration of Minamoto Shōgunate \| \|=1617=\| Foreign trade limited to two ports \| \|=1621=\| Japanese prohibited from foreign travel \| \|=1624=\| Decree of expulsion against all foreigners \| \| \| except Dutch and Chinese \| \|=1637=\| Peasant and Christian revolt \| \|=1641=\| Dutch and Chinese restricted to Nagasaki \| \|=1694=\| Development of trade-guilds \| \|=1792=\| Russian squadron visits Japanese coast \| +------+--------------------------------------------+ \| \| \| \| \| =1800-1867= \| \|=1804=\| Russia attempts unsuccessfully to open \| \| \| relations with Japan \| \|=1818=\| Captain Gordon at Yedo Bay \| \|=1844=\| Holland makes proposals for extension \| \| \| of trade \| \|=1848=\| Visit of American and French warships \| \| \| to Japanese waters \| \|=1853=\| Commodore Perry in Yedo Bay \| \|=1854=\| First Japanese Treaty with a Western \| \| \| Power (U.S.A.) in March. First Treaty \| \| \| with Great Britain in October \| \|=1855=\| Russian Treaty \| \|=1856=\| Dutch Treaty \| \|=1859=\| Readmission of Christian missionaries \| \|=1861=\| Attack on British Legation \| \|=1862=\| Murder of Mr. Richardson \| \| \| Japanese Embassy to the Treaty Powers \| \|=1863=\| Bombardment of Kago-shima by British \| \|=1864=\| Bombardment of Shimonoseki by \| \| \| international squadron \| \| \| Contest and reconciliation of the two \| \| \| great clans (Sats-cho) \| \|=1866=\| Kei-ki, last Shōgun \| \| \| New Conventions with Western Powers \| \|=1867= Accession of Mutsu-hito as Mikado \| \| \| Appointment of Europeans: French \| \| \| military and British naval instructors \| \| \| Resignation of Shōgun Kei-ki \| \| \| \| \| \| =1868-1907= \| \|=1868=\| Restoration of imperial power \| \|=1869=\| The Emperor takes up residence at \| \| \| Yedo, re-named Tokio. Emperor’s \| \| \| “charter” oath \| \| \| The Daimiyo surrender feudal rights \| \|=1871=\| Feudalism abolished \| \|=1872=\| Establishment of religious toleration \| \|=1873=\| Adoption of Gregorian Calendar \| \| \| Universal Military Service \| \|=1874=\| Saga rebellion. Formosan expedition \| \|=1875=\| Saghalin exchanged for Kuriles \| \|=1876=\| Korean Treaty \| \|=1877=\| Revolt and death of Saigo \| \|=1879=\| Annexation of Riu-Kiu Islands \| \|=1889=\| Promulgation of the Constitution. \| \| \| Establishment of local self-government. \| \| \| Anti-foreign reaction \| \|=1890=\| First Imperial Parliament. New civil \| \| \| and commercial codes \| \|=1894=\| War with China \| \|=1895=\| Victory over China. Formosa annexed \| \|=1897=\| Revised customs tariff. Gold standard. \| \| \| Freedom of Press and public meetings \| \|=1899=\| New Treaties on terms of equality. \| \| \| Opening of the whole country \| \|=1900=\| Expedition against Boxers in China \| \|=1902=\| Anglo-Japanese agreement \| \|=1904=\| War with Russia \| \|=1905=\| Victory over Russia. Japan obtains \| \| \| Port Arthur, S. Saghalin, control of \| \| \| S. Manchuria, and protectorate of \| \| \| Korea \| \| \| Anglo-Japanese alliance \| \|=1907=\| Franco-Japanese Agreement \| \| \| Russo-Japanese Convention \| \|=1910=\| Korea annexed \| \|=1911=\| Anglo-Japanese Agreement \| +------+--------------------------------------------+ [Illustration: JAPAN] THE COUNTRY AND THE PEOPLE BY ARTHUR DIOSY THE EMPIRE OF THE EASTERN SEAS [Sidenote: Length and Breadth of Great Japan] Asia’s furthest outpost towards the vast waters of the Pacific Ocean, a long, narrow chain of rocky, volcanic islands, extends north-east to south-west along the eastern coast of the mainland, separated from it by the Sea of Japan and the China Seas. A glance at the map shows this long string of more than three thousand islands and islets, stretching from 51°5′, the latitude of Shumo-shu, the most northern of the Kurile group of islands, down to 21°48′, the latitude of the South Cape of Formosa, a total length of nearly thirty degrees. Its component parts extend from 157°10′ east longitude, at Shumo-shu, as far westwards as 119°20′, the position of the extreme western islets of the Pescadores, or Hokoto, archipelago, a distance of nearly thirty-eight degrees, the total breadth of the Empire of Dai Nippon--Great Japan. The enormous length of the island empire, the configuration of which is likened by the Japanese to the slender body of a dragon-fly, provides a great variety of climate, from the Arctic rigour of the Kurile Islands and the Siberian climate, with its long and terrible winter and its short but fierce summer, obtaining in the larger northern islands, to the sweltering, steamy heat of Formosa, the tropic of Cancer passing through that island and through the Pescadores. These extreme temperatures apart--and they prevail only at the ends of the empire--Japan possesses a temperate climate, similar to that of the northern shores of the Mediterranean, but colder in winter and much damper, the excessive humidity causing both heat and cold to be very trying, though never dangerous. The rainfall is especially heavy in June and in September, but no month is entirely without rain. The hottest period of the year is called dō-yō, corresponding to our “dog-days,” and follows the rainy season of June and early July. [Sidenote: What Japan Owes to its Position] Japan owes its great humidity, the consequent fertility of such parts of its surface as are cultivable--about 84·3 per cent. of the whole area of Japan proper is too rocky to yield food for man--and the luxuriant verdure that clothes the lower slopes of its wooded hills, to its insular position, and, chiefly, to two great factors, a current and a wind. The great warm current known as the Kuro-shio, the Black Brine, or Black Tide, flowing from the tropical region between the Philippines and Formosa, raises the temperature of the east coast, and, where it is in part deflected by contact with the southern coast of Kiū-shū, also of the west coast, acting in the same beneficent manner as the Gulf Stream of the Atlantic. The wind that affects the Japanese climate most strongly is the north-east monsoon, tempered by the action of the dark, warm, ocean current. Keystone View Co. A GLIMPSE OF THE INLAND SEA, THE LOVELIEST SHEET OF WATER IN JAPAN Studded with hundreds of islands, every part of the Inland Sea of Japan, stretching 240 miles in length, and widening once to 40 miles, offers an enchanting prospect. The islands occur often in clusters, giving the appearance of lakes. ] The geographical position of Japan has had great influence on the history of its people, and clearly indicates the supremely important part the empire is destined to play in the future development of the Far East. Its insular character has preserved it from invasion--it is the proud and legitimate boast of the Japanese that no foe has, within historical times, trodden Japanese soil for more than a few hours--and whilst it rendered possible the seclusion in which the nation lived for more than two centuries, developing, undisturbed, a high civilisation of its own, the basis of many of the qualities displayed by the Japanese in our day, it has been, in recent times, the cause of Japan’s real might in the world--her sea-power, naval and commercial. The map shows the four principal islands of Japan Proper: HON-SHŪ, or Hon-dō--“Principal Circuit,” the largest island of Japan, commonly called Nippon, really the name of the whole empire, meaning “Sun-origin,” equivalent to Sunrise Land; KIŪ-SHŪ, or Nine Provinces; SHI-KOKU, or Four States; and the great northern island of YEZO, the second in size, officially termed Hok-kai-dō--“North Sea Circuit.” The four islands extend, opposite the mainland, from the coast of the Russian Maritime Province, on the north-west, down to the southern extremity of the Korean peninsula, on the south-west. North of Yezo, facing the mouth of the great River Amur, the long, narrow island of Saghalin--Karafuto, in Japanese--belongs partly to Russia, partly to Japan, its southern districts, up to the fiftieth degree of latitude, being ceded to the victors by Article IX. of the Treaty of Portsmouth (1905). Separating these islands, important channels afford communication between the Sea of Japan and the Pacific. The Gulf of Tartary divides Saghalin from the mainland, whilst the Strait of La Pérouse, or Strait of Tsugaru, separates the island from Yezo. The Straits of Korea, between that empire, now under the protectorate of Japan, and the main island, Hon-shū, or Nippon, are the way of communication joining the Sea of Japan and the eastern part of the China Sea, the straits being divided into three channels by the island of Iki and by those of Tsu-shima, a name rendered for ever glorious by Togo’s great victory on May 27th, 1905. The various straits are sufficiently narrow to be easily closed to an enemy by Japan’s splendid fleet. Keystone View Co. A CRATER WITH EIGHTY VILLAGES, IN WHICH TWENTY THOUSAND PEOPLE LIVE Twenty thousand people live in eighty villages in the outer crater of Aso-san, probably the largest crater on earth, competing, says Professor Milne, with some of the great craters of the moon. The crater of Aso-san is from 10 to 14 miles across, and its wall is everywhere 2,000 feet high, the highest peak being Taka-dake, 5,630 feet. ] Although Japan has remained immune from invasion throughout historical time, its proximity to the mainland, and especially to the Korean peninsula, led, in prehistoric ages, to its receiving from the continent an influx of immigrants who gradually conquered the insular natives, and whose descendants probably form the main stock of the present Japanese race. It was this proximity that brought the civilisation of China into Japan, in the first instance through Korea; the same route was followed by another mighty invasion of foreign thought, the introduction of Buddhism. Keystone View Co. HAKONÉ LAKE AND THE GATEWAY TO THE INARI TEMPLE IN KIŌTO Hakoné Lake, the top picture, is a delightful summer resort. The bottom picture, the avenue of Torii (portals), forming the entrance to a Shintō Temple at Kiōto, is a wonderful sight. There are over 400 Torii, arranged in two colonnades. ] Keystone View Co. A GLIMPSE OF THE BUSY NAGOYA CANAL AND OF THE PARK AT KUMAMOTO Nagoya is one of the great manufacturing cities of Japan, and a busy canal links the city with the port of Yokkaichi. The park of Suizenji, in Kumamoto, is a beautiful example of Japanese landscape gardening. ] No country has been better fashioned by Nature for the acquirement of sea-power than the Island Empire of the Rising Sun. Its enormous extent of coast-line, with countless indentations, especially numerous on the south-eastern coasts of Hon-shū, Shi-koku, and Kiū-shū, its many excellent harbours, naturally fortified by reason of the narrow entrances to the gulfs in which they are situated--for example: Nagasaki, in Kiū-shū, the naval stations at Sasebo, in the same island, Kure, in the Inland Sea, and Yoko-suka, near Tōkio Bay--and, above all, the excellence of its seafaring population, supply the elements that give Japan the mastery in Far Eastern waters. [Sidenote: Seafaring Qualities of Japanese] In the thousands of hamlets nestling in the bays, large and small, and creeks of the Japanese islands, dwells a hardy race of fishermen, inured to peril and fatigue, men of brawny strength and indomitable pluck, frugal and enduring, as fine material for the manning of warships and trading craft as the world has ever known. The persistence of those seafaring qualities which the Japanese owe chiefly to the natural advantages of their island home--partly, no doubt, to a strain of the blood of Malay sea-rovers, perhaps also of Polynesian canoe-men--is a remarkable phenomenon. In olden times they were bold seafarers, roaming as far as the Philippines and the coast of Indo-China. The waters of Formosa and of Siam were the scene of their piratical exploits, for, like all nations destined to be great at sea, they passed through a period when the spirit of adventure, as much as the lust for spoil, made them into daring sea-robbers. But, with the closing of Japan to foreign intercourse--save on a strictly limited scale--early in the seventeenth century, came the enactment of laws devised to prevent the Japanese from visiting foreign parts; the tonnage and build of ships were fixed by these decrees in such a manner that only fishing and coasting trips were thenceforward possible. This prohibition lasted for two centuries and a half; yet, on its removal, the germ of the seafaring qualities, supposed to have died out, was found to have been only in a state of suspended animation; it revived with surprising rapidity. In less than a quarter of a century it produced a naval _personnel_ capable of manning a highly efficient fleet of thirty-three sea-going fighting-ships; in ten years more the amazed world recognised Japan’s Navy as the triumphant victor in the greatest battle since Trafalgar, and coupled Admiral Togo’s name with that of Nelson. [Sidenote: The Sea as Japan’s Friend] The sea has, indeed, ever been Japan’s friend; to this day it supports a large number of the population, and, in a sense, it may be said to keep the whole nation alive, as the fish that teem in Japanese waters supply a considerable part of the people’s food. Every marine product available as nutriment is utilised, even seaweed of various kinds being largely used as food. Fishing seems to have been practised from the earliest times; it is probably in recognition of its antiquity and national importance that the Japanese of our day still affix to any gift a strip of dried seaweed, passed through a piece of paper peculiarly folded, the idea they thus symbolise being, it is said: “This is but a trumpery present, but it comes from a cheerful giver; be pleased to take it as it is meant. Remember our forefathers were poor fisherfolk; this strip of seaweed is to remind you that poverty is no crime.” [Sidenote: Japan’s Beautiful Scenery] There are many other customs connected with the harvest of the sea, and innumerable legends and folk-tales wherein the chief part is played by some marine spirit or by a visitor--deity or mortal--to the mysterious realms of the deep. And deep it is, for, off the eastern coast of Northern Japan, the sea-bed falls abruptly to a depression--the famous Tuscarora Deep, called after the United States warship of that name--of 4,655 fathoms, nearly 28,000 ft., or more than five miles, probably the deepest sea-bed in the world. The encircling sea forms an important part of most of the beautiful pictures the scenery of Japan offers to the delighted eye. Whether the waves dash tumultuously against the precipitous rocks of the south-eastern side of the main islands, especially of Shi-koku and Kiū-shū; whether the waters dance in the sunshine in the countless bays and creeks of those coasts where the frequency of the shelter afforded to fishing-craft led to an earlier and more dense settlement than on the north-west coast of Hon-shū; whether the far-famed Inland Sea shines like a mirror under the moonbeams, or the Sea of Japan tosses its grey billows or spreads a sullen expanse under the pall of fog caused by the meeting of warm and cold currents--in all its moods the ocean forms part of nearly all the grandest scenery of Japan. [Illustration: SCENES IN JAPAN AFTER AN EARTHQUAKE There is at least one shock of earthquake every day in Japan; there are 500 shocks in a year. As late as 1891 an earthquake wrecked two populous towns and destroyed two smaller ones. These photographs show the havoc of such earthquakes. ] [Illustration: YOKOHAMA: THE TOWN AND HARBOUR IN THE EARLY DAYS OF THE GREAT CHANGE] [Illustration: OLD TŌKIO: THE CITY OF YEDO, SEAT OF THE GOVERNMENT OF THE SHŌGUNS FOR HUNDREDS OF YEARS The “Japan Bridge,” one of the striking features of the capital of Old Japan, was regarded as the centre of the empire, and from it all distances were measured. ] The “Three Views,” known to every Japanese man, woman and child, for they are portrayed in countless pictorial representations, are sea-scapes. The 808 islets of Matsu-shima, with the thousand trees from which the group derives its name of Pine Islands, are the glory of the province of Sen-dai, in Northern Hon-shū; the hoary tori-i, or gateway, of the great Shin-tō temple at the sacred island of Miya-jima, or Itsuku-shima--so holy that no birth nor death may take place on the island, and no dog is allowed there--stands firmly amidst the very waves of the Inland Sea; Ama-no Hashidaté, the “Sacred Bridge,” stretches its slender two-mile length of sandy spit, only 190 ft. broad--crowned, all along, with an avenue of pine-trees--into the blue waters of the gulf of Miya-zu, in the Sea of Japan. The so-called Inland Sea, 240 miles long from its narrow western entrance, only one mile across, between Shimo-no-seki on the main island and Mo-ji, the busy colliery port in Kiū-Shū to its eastern extremity, where it joins the open sea through the Aka-shi and Naru-to Straits--it widens to forty miles where the Bungo Channel divides Shi-koku from Kiū-shū--is perhaps the most lovely sheet of salt water in the world. Studded with many hundreds of islands, every part of its expanse offers an enchanting prospect, the islets being often in clusters, making many stretches appear like lakes. Water enters into the beauty of every Japanese landscape; districts remote from the sea have their lakes and rivers--generally short, swiftly-flowing streams, almost, sometimes quite, dry in summer, exposing beds of pebbles, but rushing torrents in the wet season. Keystone View Co. MODERN YOKOHAMA: THE HARBOUR, SEEN FROM THE HEIGHTS OF THE TOWN] Biwa is the largest lake in Japan, and far-famed for its scenery; its area is about the same as that of the Lake of Geneva, and it is nearly as beautiful. Lake Chū-zen-ji, or Chū-gū-shi, is surrounded by luxuriant verdure at an altitude of 4,375 ft. above sea-level, and is surpassed in beauty by the smaller Lake Yumoto, higher up, in the sulphur-springs region, 5,000 ft. above the sea. There are many other lovely lakes in Japan, Lake Hakoné amongst them. Those just mentioned are singled out because they lie in the mountainous district round Nikkō, a region on the main islands, to the north of Tōkio, presenting, in their greatest beauty, characteristic features of Japanese inland scenery--imposing mountains, stately, venerable trees, and grand waterfalls comparable to those of Norway. The aspect of the Japanese islands is, as may be inferred, diversified, stern and rugged amidst the dark forests of the north, smiling in the sunlit regions further south, beautiful almost everywhere. [Illustration: OVERLOOKING MODERN TŌKIO, THE CAPITAL OF JAPAN] [Illustration: Looking over the Bay of 808 Islands] [Illustration: Sunset among the pine-clad rocks] A natural arch The White Co. SCENES IN MATSUSHIMA BAY, JAPAN] The land is chiefly mountainous, the ranges running from south-west to north-east, interspersed with smiling valleys, fertile plains, chequered into regular squares by the narrow, raised embankments dividing the rice-fields, with, here and there, wild, desolate moors in places where even the untiring industry and agricultural skill of the people could not induce the stubborn ground to yield sustenance. Where anything useful can possibly be made to grow, the Japanese grow it. Beside plants of utility, they grow, to a greater extent than in any other land, plants intended only for pleasure, for the delight they give the Japanese eye by their beauty. In no other country are flowers so reverently admired as in Japan; nowhere are they more skilfully grown and tended. Every month has a special blossom, and what may be termed its flower festival, when the people, high and low, rich and poor, go in their tens of thousands to seek happiness in the contemplation of Nature’s most delicate productions. The plum-blossom appears about a month after the New Year, and is followed by the far-famed cherry-flower early in April, when, in many ancient groves and on many hillsides, the lightest of delicate clouds, faintly pink, seem to have settled on the trees. No words can do justice to the exquisite beauty of Japan in cherry-blossom time; it is then easily to be understood how dear the flower of the cherry is to the Japanese heart. To the people of Great Japan it is the emblem of patriotism and of chivalry, sharing their affections with the chrysanthemum, the badge of the empire. Other flowers grown to wonderful perfection are the peony, symbolical of valour; the graceful wistaria, the glowing azalea, the slim-stalked iris, the convolvulus, or “morning-glory,” in many strange forms, and the lotus, the sacred flower of Buddhism. Besides these and other cultivated flowers, Japan possesses wild blossoms galore that fleck its plains and valleys with colour. The leaves of the maple turn, in November, to hues of crimson and gold, clothing the woods with a glory to be equalled only in Canada. The natural, beauty of Japan has undoubtedly fostered the æsthetic taste inborn with the Japanese of all classes. High and low, they admire and enjoy intensely the lovely scenes amidst which they dwell. This admiration and enjoyment are strong incentives to their patriotism. It seems to them that their beautiful country must indeed be _Kami-no-Kuni_, “the Land of the Gods.” To travelled Occidentals, the scenery of Japan suggests, in places, the Norwegian fjords; in others, the smiling shores of the Italian lakes; at some points the coves of Devonshire, the rocky coasts of the Channel Islands, or the pleasant hills of Surrey. That these impressions are correct is proved by the fact that Japanese travellers who visit any of these places never fail to recognise their similarity to some favourite spot in Japan. The “backbone” of the southern half of the main island and of the whole island of Shikoku consists of rock, principally primitive gneiss and schists; Kiū-shū, Yezo and the northern half of the main island are partly, the Kurile islands--Chishima--entirely, volcanic. Subterranean fires still smoulder in many parts of Japan, many of the mountains being volcanoes, not all of them extinct. Fuji, the glorious cone so dear to the Japanese heart, uplifting its peak 12,365 ft. from the surrounding plain, is a volcano that erupted last in January, 1708. Fifty-one volcanoes, such as Asama and Bandai-san in Eastern Japan, Aso-san in Kiū-shū, Koma-ga-také in Yezo, have been active in recent years, some of them, especially Bandai-san, with disastrous results. Nor do only volcanoes threaten danger to the inhabitants of Japan: earthquakes are frequent--about 500 shocks yearly--and sometimes appallingly destructive of life and property. The great earthquake in the Gifu region, in the central provinces of the main island, on October 28th, 1891, wrecked two populous towns--Gifu and Ōgaki--completely destroyed two smaller ones--Kasamatsu and Takegahana--killed about ten thousand people, and caused more or less severe wounds to nearly twenty thousand. In Japanese earthquakes, a great part of the destruction arises from the innumerable fires that break out when the flimsy houses--mostly of wood, with paper partitions, in sliding frames, between the rooms--collapse through the shock, scattering the glowing charcoal from the kitchens amidst heaps of highly inflammable materials. Earth-tremors bring not only fiery ruin in their train; they cause at times upheavals of the sea that work stupendous havoc. On the evening of June 15th, 1896, the north-eastern coasts of the main island were overwhelmed by a so-called “tidal wave.” The sea, impelled probably by a seismic convulsion on the bed of the Northern Pacific, rose in a wave of towering height and, rushing inland with terrific speed, engulfed whole districts. More than 28,000 lives were lost, and more than 17,000 people were injured. [Illustration: Sea-girt gateway of Miya-ima, a famous Shintō shrine The Sacred Bridge at Nikko The White Co. View of Fuji-yama across Motosu THREE FAMOUS SCENES IN JAPAN] [Illustration: THE CEMETERY HILL AT NAGASAKI BEFORE THE MODERN EXPANSION OF THE TOWN] [Illustration: THE CRATER OF FUJI, THE MOST GLORIOUS MOUNTAIN OF JAPAN, MORE THAN TWO MILES HIGH Japan has fifty volcanoes that have been active in recent years; this picture shows the crater of the most famous mountain in the island empire. Fuji, the cone so dear to the Japanese heart, uplifts its peak 12,365 feet from the plain. It has not erupted since the beginning of 1708. No other natural feature in Japan comes so often into its pictures as Fuji. ] [Illustration: MAP OF THE ISLAND EMPIRE OF JAPAN] [Illustration: JAPAN AND ITS PEOPLE--II ARTHUR DIÓSY] QUALITIES OF THE JAPANESE PEOPLE [Sidenote: The Wonderful Islanders] It is in presence of great calamities that the best qualities of the Japanese masses shine brilliantly. Their resignation, their patient endurance, the altruism that prompts them to mutual help and to countless acts of kindness; their self-sacrificing bravery in the work of rescue, the proud honesty with which they will content themselves with the barest pittance, when relief is distributed, so that enough may be left for others in greater need--these are only some of the fine characteristics of the wonderful islanders whose achievements in recent times have earned the respectful admiration of the world, even of their late foes. There is, of course, another aspect of their character; they are not without some of the vices and failings human nature is heir to. An attempt is made, later in these pages, to describe their moral and mental characteristics, and in so doing to hold the scales impartially. Underwood & Underwood THE RISING GENERATION IN JAPAN] According to the census of 1913 there were 52,985,423 subjects of the Emperor of Japan (excluding Korea), and their number is increasing steadily and rapidly. The number of males exceeds that of females by well-nigh a million. The population is very dense in the fertile regions, and increases so rapidly that emigration is absolutely necessary. The masses are healthy and strong, capable of great endurance--a fact brought into striking prominence by the achievements of the Japanese forces in the Arctic winter of Manchuria, and in its torrid summer. The Japanese can, as a rule, bear cold much better than heat. Living thinly clad in unwarmed houses that offer but little protection and are by day draughty as bird-cages, they early become inured to cold. The average physique of the upper classes is by no means so good as that of the manual workers, and is considerably below the Occidental standards. [Sidenote: A Race of Little People] The Japanese are a black-haired race, with smooth skins, varying in colour through various yellowish shades, from a hue of brown, in the case of those working in the sun, to a light tint no darker than that of the Southern European, with comparatively large skulls, prominent cheek-bones, and a tendency to projecting jaws. They are of small stature, the average height of the male being only slightly over five feet (5·02 ft.), that of the female slightly over four feet six inches (4·66 ft.). In other words, the men are of about the same average stature as European females, the women proportionately shorter. [Sidenote: The Two Types of Japanese] There are, of course, exceptions, some Japanese being of a height that would cause them to be considered tall amongst Occidentals; but they appear as giants amongst their diminutive compatriots. Both men and women have small hands and feet, those of the upper classes being beautifully shaped. Even amongst manual workers it is not rare to find, especially amongst females, hands of an aristocratic type. The shapely appearance of the feet is often spoiled by thick ankles, probably the result of wearing sandals. The black hair is abundant on the head, straight and coarse; there is hardly any on the arms, legs and chest. The eyelashes are scanty, and grow immediately out of the eyelids, without the “hem” that borders the eyelids of Occidental races. The eyes are dark, full in the broad-faced, plebeian type, narrow in the aristocratic cast of countenance. In the latter they are generally set more or less obliquely, their slanting appearance being enhanced by the fact that the aperture for the eye seems to have been cut, as it were, directly in the smooth skin, tightly stretched over the upper part of the face, not, as in the white races, in a very marked depression under the brow. [Illustration: THE CHILDREN’S FESTIVAL: FEAST OF DOLLS IN A JAPANESE HOME Japan is the land of love for children, and many quaint customs are observed for their sake. On the third day of the third month in each year the Feast of Dolls is held in thousands of Japanese homes, and the day is one of great delight. ] [Illustration: THE VARIOUS GRADES OF SOCIETY IN OLD JAPAN Society in Old Japan was based on the principle that the producer was worthy of high honour. There were four great classes. At the top were the _Shi_, the nobility and gentry, warriors, administrators, and scholars. Next were the _No_, the agricultural class; thirdly came the _Ko_, craftsmen and artists; and at the bottom were the _Sho_, traders and bankers. Some of the wealthier classes were thus at the bottom, because they were not producers but only circulators. ] [Sidenote: Physique of the Nation] [Sidenote: Cleanest Nation in the World] There are two plainly distinct types in the nation. The majority are “stocky,” rather squat people, with broad, round faces, rather thick lips and flat noses; the minority, of the aristocratic type, are more slenderly built, with long oval face and aquiline nose. In both types the trunk is long as compared with the legs, their shortness being probably due, in some measure, to the national habit of sitting on the floor, in a kneeling posture, the weight of the body being thrown back on to the heels. Sitting on benches, as in school and in barracks, necessitated by the introduction of Western educational and military methods, has somewhat improved the proportions of the Japanese body in this respect. The admirable gymnastic training given in the schools to children of both sexes, and, still more, the naval or military service to which every able-bodied Japanese adult male is liable, have done wonders in improving the physique of the nation. Statistics collected by the Army Medical Department clearly show that the race is gradually growing taller since the introduction of universal service. The Japanese grow to maturity more rapidly than Occidentals; they also age earlier. As in other countries, very old women are more numerous than very aged men. Both the slender, often weakly, upper classes and the stout plebeians are nimble in their movements, have supple limbs and remarkably skilful fingers. The workers use their toes to hold and steady the material on which they are at work, often sitting at their labour where Occidentals would stand. The great toe is well separated from the others, owing to the effect of the loop of cord passing between them to secure the sandal to the foot, the tabi, or sock, of cotton-cloth being made with a separate compartment for the great toe. The skin of the whole body is generally of satin-like smoothness, owing, no doubt, to the very hot baths--at a temperature of about 110° F.--in which all Japanese indulge at least once a day, thus maintaining their well-deserved reputation as the cleanest nation in the world. To the Occidental eye, the majority of Japanese men are not comely, although there are notable exceptions, presenting fine faces, of noble and intellectual type. The women are often very pretty, judged by the Occidental standard; they are nearly always graceful and charming, owing to their exquisite manners and gentle voice. The chief element in their charm is undoubtedly their perfect femininity. There is absolutely nothing masculine about their ways or their speech, yet, when the need arises, they are capable of courage and self-sacrifice that places them on the same high level as their heroic fellow-countrymen. It may safely be asserted that there are no more dutiful wives, no better mothers. There are certainly no daughters with a greater sense of filial piety, a virtue that forms the basis of family life in Japan. A lantern-mender A clock-maker Coopers at work Artists Plasterers at work A marionette show in the street The Royal Mail in Old Japan LIFE AND WORK IN OLD JAPAN: SOME TYPES IN THE ANCIENT CAPITAL] Peasant woman reeling silk Buddhist priest Mediæval friar Preparing cotton for spinning Servant Samurai bowing Japanese ladies at their toilet, using burnished metal mirrors Lady in walking costume A Japanese lady and her servant, showing the aristocratic and plebeian types of face Lady in walking costume SOME TYPES IN OLD JAPAN: CHIEFLY DEPICTED BY NATIVE ARTISTS] [Sidenote: The Chief Qualities of the Race] Throughout the Far East the whole social fabric is based on the family; the whole state is, indeed, considered as one great family, with the Emperor at its head. It is the mothers who train Japanese children from infancy in the spirit of reverence and obedience to parents and elders in the family circle, and to the Emperor as the supreme chief of the great national family. And well do the children assimilate the lessons of obedience and devotion so carefully inculcated by the mother, for there are none more docile than the boys and girls of Japan, whose respectful, courteous manners, not only towards their parents, but towards elder brothers and sisters, earn the admiration of Occidentals. The chief qualities of the Japanese race are patriotism--which is, with them, synonymous with loyalty--courage, filial piety, and cleanliness. In love of country, in self-sacrifice for the common weal, in loyalty to the sovereign--with them a cult--in reckless gallantry, and in bodily cleanliness, the Japanese surpass all other nations of our time. It may be truly said that patriotism is their real religion; it inspires their magnificent courage in war, on land and sea; it supplies the incentive of their lives in times of peace, all merely personal considerations being subordinate to this passionate national feeling. [Illustration: WINTER IN JAPAN; BY A JAPANESE ARTIST] The people of Japan are distinguished, besides, by quick intelligence, a remarkable power of observation--derived, no doubt, from their close study of Nature, of which they are devoted lovers--by a mastery of detail, and a very retentive memory, fostered by the system of learning by rote imported from China, together with the writing by means of ideographic signs, necessitating the memorising of thousands of characters standing for words. In politeness they stand first amongst the nations, every incident of life being attended by strictly-defined rules of social etiquette, observed by all, not only, as in Occidental countries, by the more highly educated classes. Their courtesy, though often degenerating into mere hollow formality, is based on a kindly regard for the feelings of others, a generous altruism and a consequent depreciation of self. They are hospitable and open-handed, the giving of presents attending numerous festivals and many occasions in social life. Schooled from babyhood by the rules of their rigid etiquette, Japanese, young and old, of all classes, are remarkably quiet in their demeanour, the higher ranks being extremely dignified in manner, and completely concealing their feelings under an imperturbable mask. They bear pain, both physical and mental, with Spartan stoicism, their nerves being much less easily excited than those of Occidentals, so that they have often been described as “a nation without nerves.” Their apparent contempt for death arises chiefly from the fact that, to most of them, the passing out of this world does not imply a total severance from mundane interests, their general belief being that the spirits of the departed have cognisance of the doings of those they leave behind. This idea, inseparable from the ancestor-worship that has prevailed amongst them from time immemorial, and still prevails, was well exemplified in their great struggle with Russia, their forces being buoyed up by the conviction that the spirits of all the warriors who had died for Japan were fighting side by side with their gallant successors. [Sidenote: Artistic Taste of the Japanese] The love of the beautiful in Nature, common to all members of the Japanese race, is probably one of the chief factors in the artistic feeling so highly developed among all classes. Their appreciation of beauty of form and colour, their exquisite sense of appropriateness in decoration, the delicate restraint so evident in the productions of their wonderfully skilful, patient artist-craftsmen, are too well known to require more than passing mention. Even their commonest household utensils are beautiful in shape, elegant, and well adapted to their purpose. Their innate good taste has added a delicate refinement to the vigorous art they received, in early times, from China, chiefly by way of Korea. Their æsthetic perception enables even the poorest Japanese to derive intense pleasure from the contemplation of the beautiful, thus providing them with many delights unknown to the vast majority of modern Occidentals. Combined with the simplicity and frugality of their lives, and with their naturally contented spirit, it would seem to have enabled the Japanese to solve the great problem “how to be happy, though poor.” A nation possessing, to a high degree, the virtues and qualities just enumerated would appear to be living in a perfect Utopia. There is, however, shade in the picture as well as bright light. This happy, contented, smiling people, pre-eminent in domestic virtues, industrious, fond of learning, easily governed, gentle in manners and speech, capable of rising, in moments of national emergency, to admirable heights of patriotic heroism and self-sacrifice, is, after all, human, and consequently tainted with some of the vices and many of the defects inherent in human nature. The defects of the Japanese character are, to a great extent, inseparable from their very virtues and good qualities in their extreme manifestations. Their intense patriotism is the cause of the anti-foreign spirit still, unfortunately, rife amongst them. Their country is to them “the Land of the Gods,” their nation the Elect People, living under the special protection of Heaven, whose blessings are transmitted to them by the benevolence of a superhuman sovereign, directly descended, in unbroken line, from the Sun Goddess. [Sidenote: National Pride of the Japanese] With this belief firmly rooted in the minds of the great majority of the people, it is no wonder that all those who have not the good fortune to be born Japanese appear to them not only as foreigners, but as Gentiles. The statesmen of New Japan are profuse in their assurances that it is the desire of their people to form a unit, on terms of equality, in the great family of nations. This assurance is echoed by many Japanese writers; it is in accordance with the spirit of the tolerant, all-embracing, gentle Buddhist faith, brimming over with sympathy for all living creatures; it is also in agreement with the calm, placid tenets of the Chinese philosophy that, with Buddhism, has to such a great extent moulded the thought of Japan. Yet those statesmen and writers know full well that in this respect neither Buddhism, nor Chinese philosophy, nor the cosmopolitan spirit of the middle period of the nineteenth century, nor the brotherhood of man inculcated by true Christianity, has succeeded, to any appreciable degree, in causing the Japanese to look upon foreigners as brothers, or even on the same plane with their own heaven-descended race. [Illustration: LADY AT HER TOILET: BY A JAPANESE ARTIST] The reckless bravery of the Japanese, their contempt for death, are closely related to the slight value they set upon human life and to the national delight in tales of bloodshed. Co-existent with the mildness of their manners and the placid tenor of their domestic life, there is found, deep in Japanese hearts, a wild delight in carnage, the legacy, naturally most cherished amongst those of the warrior class, of centuries of internecine warfare. The sword, “the living soul of the Samurai,” is still held in reverence as the instrument not only of national defence against the foreign foe, but of vengeance and of the chastisement of one looked upon by the wielder of the weapon as an enemy to the State. Hence the indulgence with which political assassination is still regarded by the masses in Japan. As the brutal instincts, inherited from primeval ancestors, often become manifest in an English-speaking crowd watching a football match or a boxing contest, so, in Japan, the old savagery reveals itself, time and again, at fencing bouts, the excited cries of the combatants recalling the bad, wild days of yore. [Illustration: JAPANESE ON A PILGRIMAGE] This fierce spirit seems incompatible with the noble generosity towards prisoners of war, and the tender care of the enemy’s wounded and sick, that redounded to the glory of the Japanese in both their great struggles in our time, the wars against China and against Russia. It is difficult to believe that savagery can survive in the breasts of people capable of organising such an admirable institution as the Red Cross Society of Japan, whose noble work, in war and peace, is one of the chief glories of New Japan; but it must be remembered that the young Great Power still feels itself to be undergoing probation under the eyes of an observant and critical world. The natural instinct of the Japanese warrior would lead him utterly to destroy the foe who dared to oppose his Emperor’s will, and it requires the application of the most severe discipline to make him understand that on his exercise of humane forbearance to the vanquished depends, to a great extent, his nation’s good repute among the Powers. This desire to stand well in the opinion of foreign nations has been so thoroughly inculcated in the people of New Japan that every individual brought into contact with foreigners beyond the boundaries of his native land feels that the honour of Japan is dependent on his behaviour, even in minute particulars. Hence the high reputation for excellent conduct enjoyed by Japanese students and others residing, or travelling, abroad. [Illustration: A FISH HAWKER IN JAPAN] The altruism and self-effacement, born of the family system, fostered by the division of the nation into clans--now officially abolished, but still binding huge groups of families with strong ties--and culminating in the most complete devotion to the head of the national family, the Emperor, are the causes of a peculiar defect in the Japanese character--the lack of individuality. It may be said of the Japanese that, on most important matters, they feel and think by millions. The whole system of their civilisation tends to make individual effort subservient to the common cause; the reverence and obedience inculcated from early childhood are not likely to develop the spirit of individuality. Hence the wonderful facility with which the Japanese combine to carry out any policy they recognise as needful for the public welfare once that course has been clearly indicated by their trusted leaders as one that has the Emperor’s approval. [Illustration: A PEASANT IN A RAIN CLOAK (Made of straw.) ] Japan is, for this reason, the land where leagues, unions, guilds, trusts and “combines” work with astonishing efficiency, such institutions being, by their very nature, well suited to the national character. There are, of course, exceptional Japanese who chafe under the repression of their strong individuality; these occasionally break through the national custom and strike out an independent line. Their fate is not encouraging to those who might be tempted to follow their example. Public opinion reproves them, and they are soon made to feel that their conduct is looked upon as anti-national. Those amongst them who will not bow their heads to the popular verdict, and refuse to be reduced to the level at which the nation strives to keep the individual, soon find life in their own country unbearable. In various cities of Europe, still more in those of North America, such Japanese individualists may be found living in self-imposed exile, shunned by their compatriots, until the day, which comes to most of them, when they submit and go home to resume their place in the ranks of a nation that abhors eccentricity and expects every man to fit into his proper groove in the great national machine. The mental activity of the Japanese, their respect for knowledge and for all intellectual pursuits, causing them to admire keen wits and exercise of brainpower, have probably contributed in a large measure to form one of the traits in their character that is repellant to Occidentals--their inclination to be cunning and deceitful. In spite of the high and pure ideals of their chivalry, they have not our loathing for deceit, our contempt for chicanery, our respect for the truth. A Japanese convicted of an untruth merely conceals his annoyance at being found out by a smile, sometimes by a laugh, and is not deterred from another statement at variance with facts should he consider it useful to make one. Low cunning is frequently looked upon as cleverness; the suppression of facts is so common that there is no other country where it is so difficult to arrive at the truth. The national failing of intense secretiveness arises, no doubt, from the suspicious nature of the people, who distrust not only all foreigners, but even most of their own race--a condition of mind due, to a great extent, to the widely ramified system of spying that flourished during the rule of the Tokugawa Shōguns, and still exists to a lesser degree. Their infinite capacity for attention to the most minute details leads to a certain pettiness, a disinclination to consider great abstract questions, and, consequently, to a narrowness of view that accounts for some of the blunders which occur in the execution of the otherwise marvellously efficient policy of the rulers of Japan. [Sidenote: Manners of the Haughty Samurai] The exquisite politeness of the Japanese is responsible for a great part of that insincerity with which they are taxed by Occidentals who have been much in contact with them. This extreme courtesy makes them so anxious to avoid any speech that might possibly give offence that they frequently distort the truth, suppress it entirely, or replace it by polite fiction, intended to give pleasure. It should be remembered that, in the knightly times of old--they continued until the early ’seventies of the nineteenth century--a Japanese had to be very guarded in his speech and demeanour; quite unintentionally, a word lightly spoken, an incautious gesture, might give dire offence to a Samurai--one of the gentry, privileged to wear two swords--who would be quick to resent the fancied slight to his punctilious sense of personal dignity. Insults, real, and often imaginary, were wiped out with blood. Hence the endeavour to avoid any possible cause of offence, for the same reason that made Europeans very circumspect in their behaviour in the days when gentlemen wore swords and drew them on small provocation. [Illustration: THE END OF A JAPANESE FEAST: BRINGING IN THE SEA-BREAM] To such a pitch was punctilio carried amongst Japanese gentlemen until quite recent times that they preferred death, inflicted by their own hands in the most painful manner--by self-disembowelment, or hara-kiri, more elegantly termed seppuku, or “self-immolation”--to living with a stain on their honour, such stain being often merely inability to disprove a slanderous imputation. To this day, the Japanese remain the most acutely sensitive people on the point of honour; so “touchy” are they that friendly intercourse with Occidentals is thereby rendered extremely difficult. What places an additional bar to perfect cordiality in such relations is the deplorable fact that an Occidental may unwittingly give grave offence to a Japanese without the latter giving any sign of displeasure at the time. Allowance is seldom made for the perfectly unintentional error on the part of the offender, whilst the grievance is allowed to rankle, is rarely forgiven, and never forgotten. Where an Occidental would certainly call his friend’s attention to the fact that he was displeased by some remark or action that would, no doubt, be promptly atoned for by a sincere apology, thus terminating the incident, the Japanese says nothing. He nurses his resentment, sometimes for years, until a fitting opportunity presents itself to avenge the real, or fancied, wound to his feelings by some particularly unpleasant action directed against the Occidental, all unconscious of his offence. This unfortunate peculiarity of the Japanese character is the outcome of two main currents that run through the national temperament--the spirit of secrecy, already alluded to, and the thirst for revenge. The latter, possibly due to the strain of Malay blood in the much-mixed Japanese race, is one of the chief stumbling-blocks hindering the introduction of Christianity, and has prevented Buddhism, also a religion teaching meekness, from obtaining a complete hold on the people. In its petty forms, this spirit of long-cherished spite is merely annoying; in its extreme manifestations it becomes exceedingly dangerous. It may be thought that the admirable magnanimity displayed by the Japanese towards the vanquished in their wars with China and with Russia affords evidence that the old spirit of revenge is dying out. Unfortunately, it is as strong as ever, the explanation of the apparent anomaly being that, in both cases, the foe was vanquished, and thus became, according to the principles of Japanese chivalry, an object for mercy and compassion. As long as the opponent resists, or refuses to surrender at the mercy of the conqueror, he is implacably attacked; the moment he has, metaphorically speaking, grovelled and placed the victor’s foot on his head, he is raised from the ground and treated with the greatest consideration. [Illustration: A GROUP OF CIVIL AND MILITARY OFFICIALS IN OLD JAPAN] This applies not only to warfare, but to those incidents in civil life, already alluded to, in which a Japanese considers himself aggrieved, especially when the offender is a foreigner. In such cases, humble apology for the slight, however unintentional--in fact, an attitude amounting to “I do not know what I have done to offend; but, in any case, I own I am in the wrong, and promise, with sincere apologies, not to offend again; deal with me as you think fit,” would generally ensure the restoration of good relations, provided the apology be sufficiently public to gratify the self-esteem of the Japanese. It is hardly to be expected that a self-respecting Occidental would demean himself thus to atone for an error unconsciously committed. [Sidenote: Defects of Japanese Character] Japanese self-esteem has just been mentioned; it often becomes insufferable arrogance, showing plainly, through a cloak of false modesty, “the pride that apes humility.” This arrogance, displayed chiefly towards foreigners, but also by Japanese in official positions towards their fellow-countrymen of inferior rank, is intimately connected with another national failing, excessive vanity. It is less noticeable amongst sailors and soldiers than amongst civil officials of corresponding rank. Minor failings of the Japanese are jealousy, envy of those who achieve success, and, connected with these faults, a great love of gossip and a readiness to listen to slander, or to disseminate it. [Illustration: A STREET SCENE IN A VILLAGE OF OLD JAPAN] [Sidenote: Japanese Ideas of Modesty] There are, finally, two charges to be examined that are frequently levelled at the Japanese by those who profess to know them well--the accusations of immorality, sexual and commercial. The first of these charges may be disposed of by the statement that the Japanese are about as moral in their sexual relations as the Latin nations of Europe, with the advantage slightly in favour of the Japanese. What has given them an evil repute in this respect is, probably, the fact that they consider as natural, and treat accordingly, certain evils that the Northern Occidental peoples affect to ignore. The natural, simple life led by the vast majority of Japanese predisposes them to take a natural, sensible view of matters that the less primitive conditions of Western civilisation have imbued with an objectionable significance. They see, for instance, no harm in nudity where it is unavoidable, as in bathing, or convenient, as in the performance of hard work in hot weather. A Japanese woman will feel no shame at being seen naked when entering or leaving the daily bath, but would strongly object to what she would consider the gross immodesty of exposing a considerable surface of her body in Occidental evening dress. In the first case, the nudity is looked upon as quite natural; in the second, as useless and provocative of pruriency. [Sidenote: National Honour in Commerce] As to the commercial morality of the Japanese, it is necessary to observe the great difference that exists between the position, in this respect, of Japanese State institutions, financial and commercial corporations, and firms of the first rank on the one hand, and the great mass of traders on the other. The Imperial Japanese Government, municipal corporations, and the great financial institutions and industrial and commercial associations under State control (such as subsidised steamship companies), have always met their obligations with scrupulous fidelity and are likely to continue to do so. With them the national honour is considered at stake; it is certain that the last Japanese will part with his last garment sooner than involve the national credit in disgrace by failure to meet the nation’s engagements towards the foreign creditor. [Sidenote: Results of Old Class Divisions] It is, unfortunately, quite otherwise in the case of the great bulk of the trading classes. There are, in Japan, a number of first-class firms, some of them established for centuries, whose reputation is above reproach; but between these and the majority of the merchants a great gulf is fixed. It must be remembered that, until the beginning of the New Era, in the early ’seventies of the nineteenth century, the trading community formed the lowest of the four classes, then sharply and immutably divided one from the other, composing that part of the Japanese nation that had full civil rights (below them stood only the Eta, who carried on despised occupations, involving contamination by contact with dead bodies, human or animal, and the outcast Hi-nin). [Illustration: IN THE OUTSKIRTS OF YEDO, NOW TŌKIO, THE CAPITAL OF JAPAN] The nation was divided into Shi, the nobility and gentry, the military, scholarly and administrative class; No, the agriculturists; Ko, the craftsmen, with whom the artists were counted; and Sho, the traders, placed below farmers and handicraftsmen as non-producers. The natural consequence of this low place in the social scale was a lack of self-respect on the part of those engaged in commerce and finance that led them to be unmindful of their good repute. Trade and finance were looked upon by the majority as occupations unworthy of a gentleman and beneath the callings of the peasant and the workman; every trick was considered excusable when practised by the merchant, whose whole business was looked upon as a sort of warfare, in which cunning stratagem could be legitimately employed to the end of personal gain, a purpose appearing most unworthy to the classes swayed by the old knightly spirit. The evil effects, on a class as on an individual, of a bad reputation and consequent public contempt have, unfortunately, outlived the abolition of the old social divisions. The Japanese merchants and bankers no longer form a separate and despised class; the gentry, even members of the aristocracy, are engaging every day more and more in financial, industrial and commercial pursuits, many of them with marked success, yet the old taint adheres to the bulk of the trading community. [Sidenote: The Desire to Trick the Foreigner] There are, of course, many strictly honourable dealers in Japan, even amongst the smaller tradespeople and retailers. It is amongst the wholesale merchants and the brokers that lapses from the straight path of commercial integrity are still frequent, especially in their dealings with foreigners. It is, unfortunately, still the case that an advantage gained over the foreigner, even by the most shady methods, is looked upon as, in some way, a national victory. This deplorable point of view is likely to prevail as long as Japanese nationalism exists in its extreme form. [Sidenote: Japanese National Finance] The Japanese Government has, time after time, loudly proclaimed, by the mouths of its statesmen at home, and its representatives abroad, its desire to facilitate, in every way, the introduction of foreign capital, the vital influence so urgently required for the realisation of Japan’s bold schemes of industrial and commercial development. Strange to say, this cordial invitation, though energetically responded to by the capitalists of Europe, especially of Britain, and by those of America, has not, as yet, led to the investment of any very considerable sums in Japanese enterprises, although, as is well-known, the Japanese Government has easily borrowed many millions sterling in London, New York and Paris, for purposes of State. The chief obstacle to the investment on a large scale, of foreign capital in Japanese enterprises is to be found in the fact that, forgetting that capital is, after all, a commodity, therefore subject to the laws of supply and demand, the Japanese financial and industrial classes do not realise that the capitalist, being virtually the seller, controls the price of his property. [Sidenote: The Social Qualities of the Japanese] A mistaken impression appears to prevail in Japan that foreign capital is _obliged_ to find an outlet in the Empire of the Rising Sun and must, therefore, submit to such conditions as may seem suitable to the Japanese and accept such security as the Japanese may deem sufficient. As long as this erroneous view obtains, there can be no considerable influx of foreign money into the coffers of Japanese industrial and commercial concerns. Experience is proverbially the best teacher; the dearth of funds that is certain to follow, in due time, the abnormal and feverish activity which is animating Japanese economic conditions, immediately after the successful issue of the great struggle with Russia, will undoubtedly induce a more reasonable appreciation of the circumstances. Once the Japanese have been taught by experience that they must regulate their demands by the lowest terms considered acceptable by the foreign holders of capital, a vast and profitable field will lie before those Occidental capitalists who have the advantage of expert advice in their selection of Japanese investments. As a general rule, it may be stated that intercourse with the people of Japan leaves Occidentals very favourably impressed with the social qualities of the inhabitants of the island empire. Their exquisite courtesy, their gentle manners, and the thousand ways in which they demonstrate that kindness of heart that lubricates the wheels of life’s machinery all tend to make ordinary, everyday relations with Japanese a delightful experience. It is only when the more serious aspects of life are approached that the Occidental begins to feel the wide divergence between his point of view, in nearly every important matter, and that of the Japanese. [Sidenote: Courtesy of the Japanese] It is exceedingly difficult to specify with exactitude the particular feature of the Japanese character which lies at the root of the unfortunate fact that nearly all Occidentals who have had serious dealings with the people of Dai Nippon have emerged from their experience exasperated and often disgusted. It is probable that want of candour is the trait that acts as the sharpest irritant, for it must be confessed that frankness, so highly prized by Occidentals, especially by those of the nations that “push the world along,” is neither appreciated at its true value nor generally practised by the Japanese. The very nature of their elaborate courtesy makes them shrink from that bluff frankness which obtains amongst Occidentals on a footing of intimate friendship. Even the Japanese mode of speech is a hindrance to direct statement of fact; a Japanese, asked if he has ever been in England, will reply, in his own tongue, “Yes,” and, after a pause, “I have _never_ visited England.” He would not deem it polite to shock his questioner by a direct negative! [Illustration: THE AMAZING SUICIDE: A GHASTLY FACT IN THE LIFE OF OLD JAPAN This picture represents the Japanese custom of “Hara-kiri,” or disembowelment, known also as “Seppuku,” or self-immolation, the form of suicide which was the privilege of gentry in Old Japan instead of death at the hands of the executioner. Instances of this ghastly act occurred frequently during the Russo-Japanese war, Japanese destroying themselves rather than surrender. The standing figure in the picture is the best friend of the man about to die, acting as his kai-shaku, or second, ready to strike off his head on receiving the sign from the dying man. ] Another peculiarity of the Japanese character, that is apt to loom large in Occidental eyes as a grave national failing, is the lack of the spirit of gratitude, as it is understood by the white races. The Japanese have, hitherto, never failed to deal out fair measure, according to the letter of the contract, to the numerous Occidentals whom they have employed, as advisers and instructors, in adapting Western civilisation to the material needs of their re-organised empire; their labours, as well as those of friends of Japan who have rendered voluntary, unpaid services, have also been recognised by the bestowal of marks of Imperial favour; but it is doubtful whether a real feeling of what we term gratitude has ever entered the hearts of the nation towards the many distinguished men who have given of their best to assist in the making of New Japan, or to spread a knowledge of its greatness. This doubt does not apply to the Navy and Army; those gallant forces, keeping the sacred fire of chivalry alight, show deep gratitude to the British sailors and European soldiers--French and, after them, Germans--who instructed them in the modern art of war. [Illustration: TYPICAL JAPANESE OF THE MIDDLE CLASS] Sympathy with their aspirations is, of course, cordially welcomed from every quarter by the Japanese; they are delighted to receive help of any kind from Occidental friends at such times as, in their view, render such assistance or sympathy necessary. When the occasion has passed, and they feel independent of foreign support, they not only cease to make any effort to attract, but take no pains to conceal their indifference to it. This attitude, induced by the severely practical nature of their policy, is repugnant to Occidental feeling, and has caused the accusation to be brought against the Japanese that they treat their foreign friends “like lemons, to be thrown away once the juice has been squeezed out of them.” This course of conduct should not be judged too harshly; it should be remembered that such a proud, hypersensitive nation is ever desirous of displaying its independence, and is consequently averse to appearing to solicit help or sympathy from the outside. A gifted Frenchman, a true friend of Japan, the late Félix Régamey, several of whose spirited pictures of Japan are reproduced in this History, and who did much to gain sympathy for that country amongst his compatriots at a time when they were little inclined to extend it, said to the writer: “It would, indeed, be a pleasure to help the Japanese, but they will not let one help them.” It is noticeable that this coolness towards foreign sympathy is usually coincident with a period of national elation, consequent on the victory of Japanese arms or the obtaining of some solid advantage by Japanese diplomacy. Reviewing impartially the good and the bad points of the Japanese national character, one must come to the comforting conclusion that its faults are likely to disappear, or, at least, to be considerably attenuated in the future, as Japan enters more and more into the active life of the family of nations. The pressure of the public opinion of the vast majority of civilised mankind must exercise a beneficial influence in bringing the Japanese gradually into line with ourselves where the points of view are still too widely divergent to admit of cordial co-operation between them and Occidentals. The virtues now pre-eminently Japanese may, indeed probably will, suffer to a certain extent in the process; it is the writer’s firm conviction that enough of them will remain to enable the Japanese to accomplish the glorious destiny towards which they are marching. Their patriotism, their valour, their thoroughness, their wisdom in matters of national moment, are of the virtues that make nations great. ARTHUR DIOSY	364,306	common-pile/project_gutenberg_filtered	67214	project gutenberg	project_gutenberg-dolma-0012.json.gz:3191	https://www.gutenberg.org/ebooks/67214.txt.utf-8
IMwBFrKm8Eb-N47a	Preparing for University Reading	Skill Practice: Tackling Longer Readings It’s easy to feel overwhelmed when a professor assigns you 50+ pages of reading, but you can learn to manage these larger reading assignments by using a few strategies and asking yourself some important questions. - Look at the section headings and chapter organization. - How is the reading organized? - What type of a reading is it? - How many sections are there? - Consider your purpose. - Why are you reading this chapter? Will you have to discuss it in class, use the information on the test, or do you have a different purpose? - Are certain sections of the reading more important to you (or your professor) given the purpose above? - Pace yourself. - How long will it take you to read the assigned pages? (Think about your actual reading speed and allot a realistic amount of time.) - How can it be divided into smaller, more manageable chunks? - Take notes and annotate. - Given your purpose, what kind of notes or annotations should you make? Should you underline key terms, write questions in the margins, etc.? - Summarize and reflect. - What did you learn? - How do the different sections of the reading fit together? - What parts are still confusing or difficult for you? With longer reading passages that you may have read over several days, it’s important to follow all these steps. For example, taking notes will help you remember what you’ve read and easily review it, and summarizing will help you pull all the information together. Think about these steps as you tackle the next reading passage which is over 4,000 words. Imagine your professor has asked you to write a summary of this reading and to be prepared in class to discuss what you learned. Pre-Reading Pre-Reading Activity Discuss the following questions with a partner. - What are some of the most important differences between humans that designers need to consider? How do designers take these differences into account? - Can you think of a product that is designed for most people, but doesn’t work well for you personally? What is wrong with it? For example, is it too big, heavy, or uncomfortable? Reading 4: Designing for People [1] Everything that is designed comes into contact with people at some point. This is mostly through the use of a design, but people are also involved in less direct ways, such as manufacturing, installation or maintenance. Design failure very often occurs because of designers overlook the significance of the users, builders, or other people. A consequence of the involvement of people is the complexity they bring. Just consider the numerous variations of any object around you. Why are there so many shapes of cup, of mobile phones or of cars? Why can one person seem to operate an object easily while other people find it hard? And why can’t anyone solve the problem of uncomfortable seats on an airplane? This variation and complexity arises from differences between individual people. People are not all the same and their behavior is certainly not predictable. Here are a few key variations a designer might consider: - People vary physically, meaning that design for people has to take account of a wide range of sizes, shapes and adjustments. - People have different preferences and thoughts, meaning that what they feel about design and how they interact with it varies considerably. - People have a range of circumstances and contexts (family, friends, employment, etc.). - People have different experiences and knowledge, which means that a designer might have to make a range of assumptions. All of these variations mean that designing for people can be a complex process. Dealing with this complexity is a central part of design. In this section you will look at these variations and complexities in greater detail, but this section starts by considering one obvious variation – the physical sizes of people. You will use this variation to explore how design can blend a variety of analytical and creative approaches to respond to design drivers. 4.1 People and variation Start by considering how you would begin designing an object that has to ‘fit’ to people, such as a simple desk or table. People using it will vary in size and these differences might be quite extreme (at the time of writing, the tallest person recorded had a height of 2.72 meters or almost 9 feet and the shortest woman alive is 628 mm or 2.06 feet tall). What sizes should you start with? Is a single height acceptable? If not, how many sizes might you need? Solving the problem of human variation is not a simple exercise. If you design a product to suit people at a particular height, you may then be limiting access for other people. Figure 13 shows a typical ticket machine in the UK. If you have used a machine like this, you might have wondered whether the designers took human shape and sizes into account. You may have to uncomfortably bend over to use the machine – or you might have found the machine perfectly comfortable to use. It all depends on your point of view. At some point decisions are required to be made about the properties of a design in progress. The ticket machine shown in Figure 13 had to be designed in terms of height, width and depth, in order for it to be manufactured. In making these decisions, however, you might solve the problem for some people but make it worse for others. Knowing how to think about difficult decisions like these can be useful as a designer. Because several different factors are involved, you need to use particular ways of thinking through this type of design problem. 4.2 Practical variation One way to approach a design problem is to use your own knowledge and experience. You may not be a furniture, car, or airplane designer but you probably have considerable experience sitting down! Making use of this personal knowledge might seem trivial, but it is the start of all creative problem solving. The key is turning this personal knowledge into information you can use in any design process. Activity 1: Seat and desk height Take two measurements. Measure the height from the floor to the seat of your chair, and then measure from the floor to the desk or table where you study. Make your measurements in inches and note them down somewhere for use in the next activity. Even if you don’t usually study at a desk or table, find a place like this that you can use for this activity (and the next one). Calculate the difference between these two heights in inches. What you have done in Activity 1 is to measure something that already exists. You have an existing desk and you have given a value to a property of it. Now, when you talk to other people about your desk, you’ll be able to state the height in a way that they will understand. Before you take this measured height as the perfect desk height, it is worth checking this assumption. Once again you will use a practical method to do this. Activity 2: Experimenting with desk heights Adjust the height of your desktop by using materials you have around you. For example, you could use a flat surface like a tray propped up on books. What you are looking for is some way to quickly and easily create a stable surface that you are able to use. Try working on your desk at different heights, and note down how it feels to work at each height. (Is it more or less comfortable than the original height?) Once you have found a height that feels comfortable, record the difference in height from what you were using previously. Take a few pictures of your adjusted desktop. A discussion of this activity will follow in the main text – but don’t read on until you have tried it. This technique is called design prototyping, where you create a quick physical mock-up of a design idea in order to test some aspect of that idea. It is exceptionally useful because it is quick and simple, and you get instant feedback on the problem you are exploring. Almost all design problems can be prototyped (even systems and processes) and this is a key method in any design engineer’s toolkit. The prototype you have just made can also provide two types of information. When you increased the height of your desk you might have noted whether it felt uncomfortable and whether this discomfort is acceptable or not. Or you might have compared two heights to see which one is more (or less) comfortable. You are no longer only measuring height; you are also making judgements about the desk at these heights. In both cases you now have new items of information, and they are of different types. The height of the desk is quantitative information, while what you think and feel about the new height is qualitative information. The height you are working with is fine for one person (you!) and it is possible to imagine that other people of about your own size might also be quite happy with that height. But the general problem is: what height should you use to design a desk to ‘fit’ people? In other words, you are interested in finding a height that many people will find comfortable, and one way to do this is to find out how many people might find a particular height comfortable. To expand the problem beyond your own experience, you need to use other techniques. 4.3 Numerical variation When it comes to designing for large numbers of other people, it becomes impractical to ask every individual what they think. But the same practical methods you have just used can be scaled up using statistical methods. So now you need to know how many people are the same size as you. For that, you need to make use of statistics. Box 4: Working with datasets A dataset is a collection of data, usually presented in the form of a table. In engineering, numerical data is particularly important. The range of a dataset is the difference between its largest and smallest values. It can be useful to distinguish between two different types of data: - Discrete data is data that can take only certain values. - Continuous data is data that can take any value (often over a particular range). For example, metric screws are available in certain thicknesses and lengths. The dataset of screw lengths available might include 12 mm, 16 mm, 20 mm and 25 mm. It would not include 12.312 mm or other lengths in between these standard values. This is discrete data. In contrast, a person’s height can take any value (though you might reasonably expect it to lie between the two extremes quoted earlier!). The only restriction is the accuracy to which you choose, or are practically able, to measure it. This is continuous data. Before carrying out a detailed analysis of any dataset, it is a good idea to examine the values to see if any patterns or unusual values stand out. You should never ignore data because it is different from what you were expecting, but if a dataset does contain surprising values, it is a good idea to question them in case a mistake has been made. You might look for the following: - missing data – for instance, if you are given a table of data that has obvious unexpected gaps in it. - false precision – where a number is quoted to the hundredth decimal point and that might not be reasonable given the manner the data was collected or where the data may be rounded up or down to such an extent that it is not useful for the intended purpose. - Dubious data – for instance a data point may be surprisingly large or small. This could be due to simple errors, such as a misplaced decimal point. - Coded values, where the data provider may have used a code to indicate something, such as a missing value. - Constraints – for instance, there may be some good reason why the data has to lie within a particular range. - The presence of outliers – single values that are very different from the rest of the dataset. Having checked that your dataset looks valid, you can perform calculations on it. For example, it may be useful to find the average of a set of values. You have probably come across the idea of an average before, and you may also know that there are different kinds of averages. The most useful types of averages are usually the mean and the median. Finding the mean of a dataset: To find the mean of a set of numbers, add all the numbers together and divide by however many numbers there are in the set. Finding the median of a dataset: To find the median of a set of numbers: - Sort the data into increasing (or decreasing) order. - If there is an odd number of data values, the median is the middle value. - If there is an even number of data values, the median is the mean of the middle two values. These basic statistical tools are useful when it comes to designing for people. Activity 3: Statistical methods Below are the heights of 15 people taken at random from the general population. Heights (mm): 1671, 1817, 1763, 1733, 1722, 1745, 1773, 1778, 1725, 1696, 1689, 1718, 1735, 1705, 1734. - Write down the minimum and maximum values in this dataset. Hence calculate the range of heights. ______________________________ - Calculate the mean height, based on all the data values. Give your answer to the nearest mm. ___________ - State the median height, based on all the data values. ____________ - Compare the mean and median heights to your own height, and calculate the difference to each. _____________________________ Before you move on from this activity, it is important to realize that this is not just a theoretical exercise. The example height used in part (d) of the answer to Activity 3 produces a real value (for example, for me it’s 44 mm) that can be used practically. As you know, small differences (even smaller than 44 mm) can have a significant effect. It is important to be aware of what the values used actually represent when you use any mathematical methods in design engineering. 4.4 Using numbers to design To move forward with the desk problem, you needed to know how many other people might be your height. You found a certain desk height acceptable and might reasonably assume this is a good size for every one of the same height. But how might you find out how many other people are your height? There are many sources of data on sizes, from the very general (such as people’s heights) to the exceptionally specific (such as NASA’s guide to the sizes of things in space). Two key sources where a range of human data and information can be found are the British Standards Institute (BSI) and the Health and Safety Executive (HSE). The data they provide about the size and shape of people is called anthropometric data, which consists mainly of physical characteristics and measurements. These data values are derived using statistical methods that allow generalizations to be made about human characteristics, which can be used to inform the design process. Making use of these datasets and applying knowledge of how people interact physically with objects can be a complex process and is even a separate discipline. Ergonomics is the study of physical aspects of the human body, such as size and mechanical performance, and how these can be applied to the real world. For example, in car design and manufacture, the design of a car interior has to take account of significant variation of human shape and size, and hence the range of adjustments that can be made to a car seat, seatbelt, steering wheel, etc. And that’s before you consider how these adjustments relate to one another, or are operated mechanically. One useful way of presenting data, which is particularly useful for anthropometric data, is to create a histogram. Histograms offer a convenient way of presenting data to make it easier to read for a particular purpose. Instead of using a continuous spread of data, you divide it up into ‘buckets’ (often referred to as ‘bins’ or intervals) and sort items into them. For example, you could think of it as a way of sorting people into height ranges and then working out what proportion of people are in each range. Bar charts are similar, but can be used to represent categories of things that aren’t necessarily numerical. 4.5 Visualizing numbers Histograms are used to plot quantitative data, with ranges of data grouped into intervals. For instance, Figure 14 shows a histogram of 200 people using height ranges of 20 mm, with heights measured to the nearest 1 mm. Notice that the values on the horizontal axis are continuous – the first bucket goes from 1600 mm to 1619 mm, the second from 1620 mm to 1639 mm, and so on. The vertical axis shows percentages. The area of each bar represents the percentage of people whose height falls in that range, and the sum of all the areas would equal 100%. For this data to be really useful you need a few more data points, and the ranges would be more useful if they were smaller, as in Figure 15. Based on the data in Figure 14, 18% of the population are in the 1720–1739 mm bucket. This means that 18% of people are between 1720 mm and 1739 mm tall. Another way to write this is by using a tolerance symbol (±), so in this case the tolerance is (to a good approximation) 10 mm above or below 1730 mm. This can be written as 1730 (±10) mm. Histograms and bar charts The following section provides further information about histograms and bar charts. Box 5: Histograms and bar charts Histograms: - are used to show distributions of variables - plot quantitative data, grouped into intervals, i.e. a number, or a range of numbers. In a histogram: - the bars appear in numerical order - there are no spaces between the bars (unless the number of occurrences in a particular range is zero) - the area of each bar represents a proportion, or percentage, of the total. Bar charts: are used to compare variables plot categorical data, e.g. color, flavor, gender, occupation. In a bar chart: - the bars can appear in any order - there are spaces between the bars - the height of each bar represents the quantity of interest. Looking at Figure 14 it seems that quite a few people might not be entirely happy with any one specific desk height. A next step might be to work out a bit more accurately what sort of height ranges would be acceptable to suit as many people as possible. But there are a few big assumptions in what you have just done. Firstly, it was assumed that there is a link between a person’s height and their preferred desk height. This might not be a valid correlation – arm length or sitting height might give a more appropriate relationship. Or there might not be a reliable human measure to use in this instance. Secondly, it was assumed that 20 mm is a suitable division for the buckets in Figure 14. It is possible that people in both the 1720–1739 mm and 1740–1759 mm buckets have exactly the same preference, and that 40 mm buckets would be appropriate. 4.6 Designing for people using numbers Designing for people can be a complex process for some very simple reasons. Designing the height of a desk for one person might be relatively straightforward, but making that same desk suit lots of people is quite difficult because of the variation in human sizes. Playing with data The data you have just been looking at could now be added to hundreds, thousands and even millions of additional data points. In fact, some of the anthropometric data used in the British Standards is collected from entire country populations. Each time another point is added, the shape of the histogram will change slightly. If we had enough data points we could even imagine the histogram being quite a smooth shape (Figure 16). The smooth curve in Figure 16 is called a distribution curve. This is one of a number of different types of representation of data that is useful to be aware of. It’s different to the histogram because it is smooth (continuous) and is not divided into individual (discrete) ranges of data. It is simply useful to see the shape of this data and to realize that a visual representation of information can be just as useful as a mathematical one. By playing with this data visually, you can see some useful things about any design problem. In particular, you may now be able to visualize just how exclusive some design decisions can be; the decision to use a particular height might exclude a whole section of a population from that product. Clearly, seeing the world from a range of different users’ perspectives can have a dramatic effect on the design process. 4.7 Summary of Section 4 It is no trivial matter to physically design something for people to use. The ergonomics of design engineering can be a very complex aspect of design, but simply being aware of people’s sensitivity to physical variation can be useful as a designer. Even better, perhaps, is to realize that placing people at the center of any design process can help you to tackle difficult ‘human’ design problems. As you have seen, designing for the ‘average’ or majority in a population means you often ignore other large parts of the population. This can have a particularly significant effect on population groups that lie outside the average groupings, such as children, older people or wheelchair users. One way of approaching this is to design in order to suit as many people as possible, or even for all people in any population. This is known as inclusive or universal design. Taking this approach for the desk example, the challenge is to create a surface that is suitable for as much of the population as possible. This then becomes the new design driver – to solve the problem of a desk that is adjustable to suit a wide range of users. This changes the original design question, but it also expands the potential user market. Remember, you started considering only your own height and preference (a market of 1 person) – designing for a wider range of the population automatically means creating a more accessible product for all users of that design. In fact, most desks attempt to do precisely this and have adjustable feet to ensure that they are adaptable to as wide a range of people as is reasonably possible. But physical variation is not the only human issue a designer must consider – the attitude and thinking of people is also a hugely important area of study. Like ergonomics, this is almost a whole discipline in itself, called human factors. It deals with how people think, react and interact with products, systems and services. As with ergonomics, it is essential to recognize how important this can be for the success of any design. Research shows that the way people feel about a design has a huge impact on how they use that design – whether they persist with it, use it correctly or simply ignore it. Take your desk height as an example. If the desk were to be fully prototyped using different materials, you might feel very differently about each height depending only on the material. Some research even shows that your posture, or how you sit, changes depending on how much you like your desk! Similarly, the design of instrument and control panels for complex systems has to consider how people read, use and interact with them – the design cannot only consider functional requirements. Modern cockpits in large commercial airplanes, for example, are designed specifically to take account of how people use and interact with the instruments; Figure 17 shows an example. Designing with the user in mind throughout the process is known as user-centered design. By placing the user of a design at the center of the design process, the focus of the project shifts from what is often a static perspective (considering certain aspects only) to a more active view of design (how certain aspects work in the real world). Unfortunately, changes in airplane design came only after a series of major failures, where it was recognized that changing the way information was presented to pilots would allow them to make better decisions. The lesson from this is simple – never ignore the user in any design project. This section has guided you through a short design process. It started with a general exploration of desk height; you then made use of direct knowledge, then tried something to test your ideas and finally checked what you did. If you were to repeat this process and improve the starting question, you would be able to repeat and improve what you did each time. This repetition and improvement is known as iteration, and it is the essence of design – starting somewhere, thinking about it, doing something, then checking it, and repeating the whole cycle until it works the way it needs to. At each stage you also used a range of types of thinking and processes, both analytical and creative, to ‘think through’ the problem one step at a time. Each time you did this, what you found informed the next stage in the process – all with the overarching aim of responding to the original question posed. Design is not simply doing one thing or applying one kind of approach – it is a process that incorporates a range of skills, attitudes and approaches. Conclusion Hopefully your existing ideas of what design is have been challenged so you now think of design in other ways too. You have seen that design is more than simply choosing the shape and appearance – it’s a fundamental human ability to take existing conditions and change them with a clear purpose. Design responds to real world situations and challenges, most of which are driven by human needs and desires. These design drivers are major factors in motivating designers but designing for humans is still unquestionably a difficult task. You have also been introduced to some numerical methods that can be applied in design, showing that it’s not only creative thinking that’s necessary – good analytical thinking is needed too. The key to good design is knowing when to apply each of these to best effect in the design process. As a design engineer, you make use of both creative and analytical thinking, taking human imagination and creativity and making it a working reality. Reading Comprehension Choose the best answer to the following questions. - What is the main idea of the reading? - Some objects are not perfectly designed for all people. - Human variation affects design decisions. - Designers need to study human differences. - Designers must be inclusive of people with disabilities. - Why did the author want you to complete “Activity 2”? - to demonstrate the concept of prototyping - to show human variation in relation to desks - to have students design something easily - to entertain students during a long reading - According to the reading, why should you never ignore surprising data? - The data might represent your ideal customer. - There might be unreasonable constraints. - The average or mean may not be useful. - There may be a mistake in its coding or collection. - What is ergonomics? - the study of human differences and how that affects people’s work - the science of making things for people who are different from the norm - the study of anthropometric data about humans and their differences - the science of designing things that are safe and comfortable for people - Why is universal design important? - It means products can be used by a variety of people. - It signifies that products can be used around the world without difficulty. - It shows that the designer has thought about product variations. - It tells consumers that something is designed for the average person. Answer the questions in your own words. - Write a 7-10 sentence summary of reading 4. - What did you learn from the reading? - What was the most interesting part of the reading for you? - Write three discussion questions to use in your in-class discussion with your classmates. Circle the word that best completes the sentence. - To calculate the (mean / median), add all the numbers together and divide by the total number of items in the group. - When data can be any number within a certain range, then the data is called (discrete data / continuous data). - A (histogram / bar chart) shows how often the data falls within a particular interval or range. Vocabulary Practice Complete the paragraphs below using the words in the box. You may need to change the verb to fit. \| intervals qualitative random stable straightforward \| After years of research, a pharmaceutical company is ready to launch its new drug. During the testing phase, patients were assigned to two (1) _________________________ groups. One group was given the new drug and monitored over the course of ten years, at two-year (2)_________________________. The medical tests showed clear improvements, and patients reported feeling significantly better in (3)_________________________ interviews. Their condition remained (4)_________________________ for years while those who did not receive the drug continued to have worsening symptoms. While the research process wasn’t simple or (5)_________________________, the company is encouraged by the results and looks forward to releasing the new drug. \| discrete dynamic precision sum visualize \| A furniture company is hiring new sales associates. They are looking for smart, energetic, and (6)_________________________ people. The job also requires (7)_________________________ because associates will need to take exact measurements. They will need to help clients (8)_________________________ the furniture in the clients’ spaces. But, more than any (9)_________________________ skills, the company hopes to find someone who can be successful in the fast-paced environment. In return, they are offering a large (10)_________________________ of money after each sale and a strong base salary. Reading Discussion Discuss these questions with your classmates. - Did you finish this reading in one sitting? How long did it take? How difficult was it? - What strategies for “tackling longer reading passages” did you use? Which will you try next time? - What kind of notes or annotations did you make? Is anything in the passage still confusing? - How could you apply what you learned in this reading to another design problem? - Download the original, un-adapted version for free at https://www.open.edu/openlearn/science-maths-technology/engineering-technology/introduction-design-engineering/content-section-4 ↵	6,779	common-pile/pressbooks_filtered	https://pimaopen.pressbooks.pub/preparingforreading/chapter/reading-4-designing-for-people/	pressbooks	pressbooks-0000.json.gz:34100	https://pimaopen.pressbooks.pub/preparingforreading/chapter/reading-4-designing-for-people/
BAjxbz6BJH9OWixW	Writing the Nation: A Concise Introduction to American Literature 1865-Present	Learning Outcomes After completing this chapter, you should be able to: - Describe the post-Civil War context of American culture at the time Realistic writing came into prominence. - List the features of American Literary Realism. - List the features of the two sub-movements that preceded Realism: Local Color and Regionalism. - Identify stylistic elements of Local Color, Regionalism, and Realism in literary selections. - Identify major distinctions and differences among the literary styles of Local Color, Regionalism, and Realism. - Analyze the ways in which women’s literature develops in this period. - Analyze themes in an early work by an African-American writer.	133	common-pile/pressbooks_filtered	https://pressbooks.nvcc.edu/writingthenation/chapter/learning-outcomes-2/	pressbooks	pressbooks-0000.json.gz:94008	https://pressbooks.nvcc.edu/writingthenation/chapter/learning-outcomes-2/
vduF6As8SmA17sEY	12.6: Supply Chain Management Logistics	12.6: Supply Chain Management Logistics What you’ll learn to do: explain the importance of supply chain management and logistics In this section you’ll learn about the role of supply chain management and logistics in the production of goods and services. Learning Objectives - Differentiate between supply chain management and logistics - Differentiate between inbound and outbound logistics Supply Chain Management and Logistics The following video provides an overview of the importance of supply chain management and logistics. Supply Chain Management As you saw in the video, supply chain management is the process of managing the movement of the raw materials and parts from the beginning of production through delivery to the consumer. In many organizations, operational supply chain decisions are made hundreds of times each day affecting how products are developed, manufactured, moved, and sold. The complexity of the supply chain varies with the size of the business and the intricacy and quantity of items manufactured, but most supply chains have elements in common, such as the following: - Customers: Customers start the chain of events when they decide to purchase a product that has been offered for sale by a company. If the product has to be manufactured, the sales order will include a requirement that needs to be fulfilled by the production facility. - Planning: The planning department will create a production plan to produce the products to fulfill the customer’s orders. To manufacture the products, the company will then have to purchase the raw materials needed. - Purchasing : The purchasing department receives a list of raw materials and services required by the production department to complete the customers’ orders. - Inventory: The raw materials are received from the suppliers, checked for quality and accuracy, and moved into the warehouse. - Production: Based on a production plan, the raw materials are moved to the production area. These raw materials are used to manufacture the finished products ordered by the customer and then sent to the warehouse where they await shipping. - Transportation: When the finished product arrives in the warehouse, the shipping department determines the most efficient method to ship the products so they are delivered on or before the date specified by the customer. Take a look at the following video about BYU ice-cream production. Can you identify each of the elements, above, in BYU’s supply chain? Logistics When used in a business sense, logistics is the management of the flow of things between the point of origin and the point of consumption in order to meet requirements of customers or corporations. The resources managed in logistics can include physical items such as food, materials, animals, equipment, and liquids, as well as abstract items, such as time and information. The logistics of physical items usually involves the integration of information flow, material handling, production, packaging, inventory, transportation, and warehousing. There is often confusion over the difference between logistics and supply chains. It is now generally accepted that logistics refers to activities within one company/organization related to the distribution of a product, whereas supply chain also encompasses manufacturing and procurement and therefore has a much broader focus, as it involves multiple enterprises, including suppliers, manufacturers, and retailers, working together to meet a customer’s need for a product or service. One way to look at business logistics is “having the right item in the right quantity at the right time at the right place for the right price in the right condition to the right customer.” An operations manager who focuses on logistics will be concerned with issues such as inventory management, purchasing, transportation, warehousing, and the planning and organization of these activities. Logistics may have either an internal focus (inbound logistics) or an external focus (outbound logistics). Inbound Logistics A manager in charge of inbound logistics manages everything related to the incoming flow of resources that the company needs to produce its goods or services. These activities will include managing supplier relationships, accessing raw materials, negotiating materials pricing, and arranging quicker delivery. Outbound Logistics A manager working in outbound logistics will be focused on two issues: storage and transportation. He or she will use warehousing techniques to keep the finished goods safe and accessible. Since the products may need to be moved out to a customer at any moment, proper organization is crucial. Having as little product stored as possible can be advantageous since stored products are not making money, so the outbound logistics manager often has to balance company cost savings with consumer demand. The transportation function is by far the most complex part of outbound logistics. Without transport, there simply is no logistics. For that reason it’s critical to be able to move the product from one location to another in the fastest, most cost-effective, and efficient way possible. Since transportation involves fluctuations, factors such as delays and changes in fuel costs need to be taken into account in order to cover all possible scenarios that might jeopardize the efficient movement of goods.	1,076	common-pile/libretexts_filtered	https://biz.libretexts.org/Bookshelves/Business/Introductory_Business/Book%3A_Introduction_to_Business_(Lumen)/12%3A_Managing_Process/12.06%3A_Supply_Chain_Management_Logistics	libretexts	libretexts-0000.json.gz:18656	https://biz.libretexts.org/Bookshelves/Business/Introductory_Business/Book%3A_Introduction_to_Business_(Lumen)/12%3A_Managing_Process/12.06%3A_Supply_Chain_Management_Logistics
l2EkqH82ByLR08ZQ	20.E: Between the Stars - Gas and Dust in Space (Exercises)	20.E: Between the Stars - Gas and Dust in Space (Exercises) For Further Exploration Articles Goodman, A. “Recycling the Universe.” Sky & Telescope November (2000): 44. Review of how stellar evolution, the interstellar medium, and supernovae all work together to recycle cosmic material. Greenberg, J. “The Secrets of Stardust.” Scientific American December (2000): 70. The makeup and evolutionary role of solid particles between the stars. Knapp, G. “The Stuff between the Stars.” Sky & Telescope May (1995): 20. An introduction to the interstellar medium. Nadis, S. “Searching for the Molecules of Life in Space.” Sky & Telescope January (2002): 32. Recent observations of water in the interstellar medium by satellite telescopes. Olinto, A. “Solving the Mystery of Cosmic Rays.” Astronomy April (2014): 30. What accelerates them to such high energies. Reynolds, R. “The Gas between the Stars.” Scientific American January (2002): 34. On the interstellar medium. Websites and Apps Barnard, E. E., Biographical Memoir: www.nasonline.org/publication...ard-edward.pdf. Cosmicopia: helios.gsfc.nasa.gov/cosmic.html. NASA’s learning site explains about the history and modern understanding of cosmic rays. DECO: https://wipac.wisc.edu/deco . A smart-phone app for turning your phone into a cosmic-ray detector. Hubble Space Telescope Images of Nebulae: http://hubblesite.org/gallery/album/nebula/ . Click on any of the beautiful images in this collection, and you are taken to a page with more information; while looking at these images, you may also want to browse through the slide sequence on the meaning of colors in the Hubble pictures ( http://hubblesite.org/gallery/behind...ning_of_color/ ). Interstellar Medium Online Tutorial: www-ssg.sr.unh.edu/ism/intro.htm. Nontechnical introduction to the interstellar medium (ISM) and how we study it; by the University of New Hampshire astronomy department. Messier Catalog of Nebulae, Clusters, and Galaxies: http://astropixels.com/messier/messiercat.html . Astronomer Fred Espenak provides the full catalog, with information and images. (The Wikipedia list does something similar: en.Wikipedia.org/wiki/List_o...ssier_objects.) Nebulae: What Are They?: http://www.universetoday.com/61103/what-is-a-nebula/ . Concise introduction by Matt Williams. Videos Barnard 68: The Hole in the Sky: https://www.youtube.com/watch?v=8No6I0Uc3No . About this dark cloud and dark clouds in interstellar space in general (02:08). Horsehead Nebula in New Light: www.esa.int/spaceinvideos/Vid...a_in_new_light. Tour of the dark nebula in different wavelengths; no audio narration, just music, but explanatory material appears on the screen (03:03). Hubblecast 65: A Whole New View of the Horsehead Nebula: http://www.spacetelescope.org/videos/heic1307a/ . Report on nebulae in general and about the Horsehead specifically, with ESO astronomer Joe Liske (06:03). Interstellar Reddening: https://www.youtube.com/watch?v=H2M80RAQB6k . Video demonstrating how reddening works, with Scott Miller of Penn State; a bit nerdy but useful (03:45). Collaborative Group Activities - The Sun is located in a region where the density of interstellar matter is low. Suppose that instead it were located in a dense cloud 20 light-years in diameter that dimmed the visible light from stars lying outside it by a factor of 100. Have your group discuss how this would have affected the development of civilization on Earth. For example, would it have presented a problem for early navigators? - Your group members should look through the pictures in this chapter. Are there any clues either in the images or in the captions? Are the clouds they are part of significantly bigger than the nebulae we can see? Why? Suggest some ways that we can determine the sizes of nebulae. - How do the members of your group think astronomers are able to estimate the distances of such nebulae in our own Galaxy? (Hint: Look at the images. Can you see anything between us and the nebula in some cases. Review Celestial Distances, if you need to remind yourself about methods of measuring distances.) - The text suggests that a tube of air extending from the surface of Earth to the top of the atmosphere contains more atoms than a tube of the same diameter extending from the top of the atmosphere to the edge of the observable universe. Scientists often do what they call “back of the envelope calculations,” in which they make very rough approximations just to see whether statements or ideas are true. Try doing such a “quick and dirty” estimate for this statement with your group. What are the steps in comparing the numbers of atoms contained in the two different tubes? What information do you need to make the approximations? Can you find it in this text? And is the statement true? - If your astronomy course has involved learning about the solar system before you got to this chapter, have your group discuss where else besides interstellar clouds astronomers have been discovering organic molecules (the chemical building blocks of life). How might the discoveries of such molecules in our own solar system be related to the molecules in the clouds discussed in this chapter? - Two stars both have a reddish appearance in telescopes. One star is actually red; the other’s light has been reddened by interstellar dust on its way to us. Have your group make a list of the observations you could perform to determine which star is which. Have your group discuss what images from this book you would use in your talk. In what order? What is the one big idea you would like the students to remember when the class is over? - This chapter and the next (on The Birth of Stars) include some of the most beautiful images of nebulae that glow with the light produced when starlight interacts with gas and dust. Have your group select one to four of your favorite such nebulae and prepare a report on them to share with the rest of the class. (Include such things as their location, distance, size, way they are glowing, and what is happening within them.) Review Questions - Identify several dark nebulae in photographs in this chapter. Give the figure numbers of the photographs, and specify where the dark nebulae are to be found on them. - Why do nebulae near hot stars look red? Why do dust clouds near stars usually look blue? - Describe the characteristics of the various kinds of interstellar gas (HII regions, neutral hydrogen clouds, ultra-hot gas clouds, and molecular clouds). - Prepare a table listing the different ways in which dust and gas can be detected in interstellar space. - Describe how the 21-cm line of hydrogen is formed. Why is this line such an important tool for understanding the interstellar medium? - Describe the properties of the dust grains found in the space between stars. - Why is it difficult to determine where cosmic rays come from? - What causes reddening of starlight? Explain how the reddish color of the Sun’s disk at sunset is caused by the same process. - Why do molecules, including $\ce{H2}$ and more complex organic molecules, only form inside dark clouds? Why don’t they fill all interstellar space? - Why can’t we use visible light telescopes to study molecular clouds where stars and planets form? Why do infrared or radio telescopes work better? - The mass of the interstellar medium is determined by a balance between sources (which add mass) and sinks (which remove it). Make a table listing the major sources and sinks, and briefly explain each one. - Where does interstellar dust come from? How does it form? Thought Questions - Figure $20.1.1$ in Section 20.1 shows a reddish glow around the star Antares, and yet the caption says that is a dust cloud. What observations would you make to determine whether the red glow is actually produced by dust or whether it is produced by an H II region? - If the red glow around Antares is indeed produced by reflection of the light from Antares by dust, what does its red appearance tell you about the likely temperature of Antares? Look up the spectral type of Antares in Appendix J. Was your estimate of the temperature about right? In most of the images in this chapter, a red glow is associated with ionized hydrogen. Would you expect to find an H II region around Antares? Explain your answer. - Even though neutral hydrogen is the most abundant element in interstellar matter, it was detected first with a radio telescope, not a visible light telescope. Explain why. (The explanation given in Analyzing Starlight for the fact that hydrogen lines are not strong in stars of all temperatures may be helpful.) - The terms H II and H2 are both pronounced “H two.” What is the difference in meaning of those two terms? Can there be such a thing as H III? - Suppose someone told you that she had discovered H II around the star Aldebaran. Would you believe her? Why or why not? - Describe the spectrum of each of the following: - starlight reflected by dust, - a star behind invisible interstellar gas, and - an emission nebula. - According to the text, a star must be hotter than about 25,000 K to produce an H II region. Both the hottest white dwarfs and main-sequence O stars have temperatures hotter than 25,000 K. Which type of star can ionize more hydrogen? Why? - From the comments in the text about which kinds of stars produce emission nebulae and which kinds are associated with reflection nebulae, what can you say about the temperatures of the stars that produce NGC 1999 (Figure $20.3.5$ in Section 20.3)? - One way to calculate the size and shape of the Galaxy is to estimate the distances to faint stars just from their observed apparent brightnesses and to note the distance at which stars are no longer observable. The first astronomers to try this experiment did not know that starlight is dimmed by interstellar dust. Their estimates of the size of the Galaxy were much too small. Explain why. - New stars form in regions where the density of gas and dust is relatively high. Suppose you wanted to search for some recently formed stars. Would you more likely be successful if you observed at visible wavelengths or at infrared wavelengths? Why? - Thinking about the topics in this chapter, here is an Earth analogy. In big cities, you can see much farther on days without smog. Why? - Stars form in the Milky Way at a rate of about 1 solar mass per year. At this rate, how long would it take for all the interstellar gas in the Milky Way to be turned into stars if there were no fresh gas coming in from outside? How does this compare to the estimated age of the universe, 14 billion years? What do you conclude from this? - The 21-cm line can be used not just to find out where hydrogen is located in the sky, but also to determine how fast it is moving toward or away from us. Describe how this might work. - Astronomers recently detected light emitted by a supernova that was originally observed in 1572, just reaching Earth now. This light was reflected off a dust cloud; astronomers call such a reflected light a “light echo” (just like reflected sound is called an echo). How would you expect the spectrum of the light echo to compare to that of the original supernova? - We can detect 21-cm emission from other galaxies as well as from our own Galaxy. However, 21-cm emission from our own Galaxy fills most of the sky, so we usually see both at once. How can we distinguish the extragalactic 21-cm emission from that arising in our own Galaxy? (Hint: Other galaxies are generally moving relative to the Milky Way.) - We have said repeatedly that blue light undergoes more extinction than red light, which is true for visible and shorter wavelengths. Is the same true for X-rays? Look at Figure $20.6.1$ in Section 20.6. The most dust is in the galactic plane in the middle of the image, and the red color in the image corresponds to the reddest (lowest-energy) light. Based on what you see in the galactic plane, are X-rays experiencing more extinction at redder or bluer colors? You might consider comparing Figure $20.6.1$ in Section 20.6 to Figure $20.3.6$ in Section 20.3. - Suppose that, instead of being inside the Local Bubble, the Sun were deep inside a giant molecular cloud. What would the night sky look like as seen from Earth at various wavelengths? - Suppose that, instead of being inside the Local Bubble, the Sun were inside an H II region. What would the night sky look like at various wavelengths? Figuring for Yourself - A molecular cloud is about 1000 times denser than the average of the interstellar medium. Let’s compare this difference in densities to something more familiar. Air has a density of about 1 kg/m 3 , so something 1000 times denser than air would have a density of about 1000 kg/m 3 . How does this compare to the typical density of water? Of granite? (You can find figures for these densities on the internet.) Is the density difference between a molecular cloud and the interstellar medium larger or smaller than the density difference between air and water or granite? - Would you expect to be able to detect an H II region in X-ray emission? Why or why not? (Hint: You might apply Wien’s law) - Suppose that you gathered a ball of interstellar gas that was equal to the size of Earth (a radius of about 6000 km). If this gas has a density of 1 hydrogen atom per cm 3 , typical of the interstellar medium, how would its mass compare to the mass of a bowling ball (5 or 6 kg)? How about if it had the typical density of the Local Bubble, about 0.01 atoms per cm 3 ? The volume of a sphere is $V = \left( \frac{4}{3} \right) \pi R^3$. - At the average density of the interstellar medium, 1 atom per cm 3 , how big a volume of material must be used to make a star with the mass of the Sun? What is the radius of a sphere this size? Express your answer in light-years. - Consider a grain of sand that contains 1 mg of oxygen (a typical amount for a medium-sized sand grain, since sand is mostly $\che{SiO2}$). How many oxygen atoms does the grain contain? What is the radius of the sphere you would have to spread them out over if you wanted them to have the same density as the interstellar medium, about 1 atom per cm 3 ? You can look up the mass of an oxygen atom. - H II regions can exist only if there is a nearby star hot enough to ionize hydrogen. Hydrogen is ionized only by radiation with wavelengths shorter than 91.2 nm. What is the temperature of a star that emits its maximum energy at 91.2 nm? (Use Wien’s law from Radiation and Spectra.) Based on this result, what are the spectral types of those stars likely to provide enough energy to produce H II regions? - In the text, we said that the five-times ionized oxygen (OVI) seen in hot gas must have been produced by supernova shocks that heated the gas to millions of degrees, and not by starlight, the way H II is produced. Producing OVI by light requires wavelengths shorter than 10.9 nm. The hottest observed stars have surface temperatures of about 50,000 K. Could they produce OVI? - Dust was originally discovered because the stars in certain clusters seemed to be fainter than expected. Suppose a star is behind a cloud of dust that dims its brightness by a factor of 100. Suppose you do not realize the dust is there. How much in error will your distance estimate be? Can you think of any measurement you might make to detect the dust? - How would the density inside a cold cloud ($T$ = 10 K) compare with the density of the ultra-hot interstellar gas ($T$ = 106 K) if they were in pressure equilibrium? (It takes a large cloud to be able to shield its interior from heating so that it can be at such a low temperature.) (Hint: In pressure equilibrium, the two regions must have $nT$ equal, where $n$ is the number of particles per unit volume and $T$ is the temperature.) Which region do you think is more suitable for the creation of new stars? Why? - The text says that the Local Fluff, which surrounds the Sun, has a temperature of 7500 K and a density 0.1 atom per cm 3 . The Local Fluff is embedded in hot gas with a temperature of 106 K and a density of about 0.01 atom per cm 3 . Are they in equilibrium? (Hint: In pressure equilibrium, the two regions must have $nT$ equal, where $n$ is the number of particles per unit volume and $T$ is the temperature.) What is likely to happen to the Local Fluff?	3,636	common-pile/libretexts_filtered	https://phys.libretexts.org/Bookshelves/Astronomy__Cosmology/Astronomy_1e_(OpenStax)/20%3A_Between_the_Stars_-_Gas_and_Dust_in_Space/20.E%3A_Between_the_Stars_-_Gas_and_Dust_in_Space_(Exercises)	libretexts	libretexts-0000.json.gz:45006	https://phys.libretexts.org/Bookshelves/Astronomy__Cosmology/Astronomy_1e_(OpenStax)/20%3A_Between_the_Stars_-_Gas_and_Dust_in_Space/20.E%3A_Between_the_Stars_-_Gas_and_Dust_in_Space_(Exercises)
krijjHNESbHB91bd	13: Characters and Diversification Rates	13: Characters and Diversification Rates Many evolutionary models postulate a link between species characteristics and speciation, extinction, or both. These hypotheses can be tested using state-dependent diversification models, which explicitly consider the possibility that species’ characters affect their diversification rates. State-dependent models as currently implemented have some potential problems, but there are methods to deal with these critiques. The overall ability of state-dependent models to explain broad patterns of evolutionary change remains to be determined, but represents a promising avenue for future research. - - 13.1: The Evolution of Self-Incompatibility - Some species of angiosperms can avoid self-fertilization through self-incompatibility. In plants with self-incompatibility, the process by which the sperm meets the egg is interrupted at some stage if pollen grains have a genotype that is the same as the parent. This prevents self-fertilization – and also prevents sexual reproduction with plants that have the same genotype(s) at loci involved in the process. - - 13.2: A State-Dependent Model of Diversification - The models that we will consider in this chapter include trait evolution and associated lineage diversification. In the simplest case, we can consider a model where the character has two states, 0 and 1, and diversification rates depend on those states. We need to model the transitions among these states, which we can do in an identical way to what we did previously with a continuous-time Markov model. - - 13.3: Calculating Likelihoods for State-Dependent Diversification Models - To calculate likelihoods for state-dependent diversification models we use a pruning algorithm with calculations that progress back through the tree from the tips to the root. We have already used this approach to derive likelihoods for constant rate birth-death models on trees and this derivation is similar. - - 13.4: ML and Bayesian Tests for State-Dependent Diversification - Now that we can calculate the likelihood for state-dependent diversification models, formulating ML and Bayesian tests follows the same pattern we have encountered before. For ML, some comparisons are nested and so you can use likelihood ratio tests. - - 13.5: Potential Pitfalls and How to Avoid Them - The most serious limitation of state-dependent models as currently implemented is that they consider only a relatively small set of possible models. In particular, the approach we describe above compares two models: first, a model where birth and death rates are constant and do not depend on the state of the character; and second, a model where birth and death rates depend only on the character state.	538	common-pile/libretexts_filtered	https://bio.libretexts.org/Bookshelves/Evolutionary_Developmental_Biology/Phylogenetic_Comparative_Methods_(Harmon)/13%3A_Characters_and_Diversification_Rates	libretexts	libretexts-0000.json.gz:23785	https://bio.libretexts.org/Bookshelves/Evolutionary_Developmental_Biology/Phylogenetic_Comparative_Methods_(Harmon)/13%3A_Characters_and_Diversification_Rates
VC4WLs-nVi6bMV58	1.5: The Crime Control and Due Process Models	1.5: The Crime Control and Due Process Models The criminal justice system can be quite complicated, especially in the attempt to punish offenders for wrongs committed. Society expects the system to be efficient and quick, but the protection of individual rights and justice is fairly delivered. Ultimately, the balance of these goals is ideal, but it can be challenging to control crime and quickly punish offenders, while also ensuring our constitutional rights are not infringed upon while delivering justice. In the 1960s, legal scholar Herbert L. Packer created models to describe exceeding expectations of the criminal justice system. These two models can be competing ideologies in criminal justice, but we will discuss how these models can be merged or balanced to work together. The first tension between these models is often the values they place as most important in the criminal justice system. These two models are referred to as the crime control model and the due process model. The crime control model focuses on having an efficient system, with the most important function being to suppress and control crime to ensure that society is safe and there is public order. Under this model, controlling crime is more important than individual freedom. This model is a more conservative perspective. In order to protect society and make sure individuals feel free from the threat of crime, the crime control model advocates for swift and severe punishment for offenders. Under this model, the justice process may resemble an assembly-line. Law enforcement suspects; they apprehend suspects; the courts determine guilt; and guilty people receive appropriate, and severe, punishments through the correctionalsystem.The crime control model may be more likely to take a plea bargain because trials may take too much time and slow down the process. Imagine you are working out at the local gym, and a man starts shooting people. This man has no mask on,so he is easy to identify. People call 911,police promptly respond,and arrest the shooter within minutes. Under the crime control model, the police should not have to worry too much about how evidence gets collected and expanded. Investigative, arrest,and search powers would be considered necessary. A crime control model would see no need to waste time or money by ensuring due process rights. Legal technicalities, such as warrantless searches of the suspect's home, would obstruct the police from effectively controlling crime. Effective use of time would be to immediately punish, especially since the gym had cameras and the man did not attempt to hide his identity. Any risk of violating individual liberties would be considered secondary to the need to protect and ensure the safety of the community in this model. Additionally, the criminal justice system is responsible for ensuring victim’s rights, especially helping provide justice for those murdered at the gym. Using the same example of the gym murder, the due process model would want to see all the formalized legal practices afforded to this case in order to hold him accountable for the shooting. If this man did not receive fair and equitable treatment, then the fear is this can happen to other cases and offenders. Therefore, due process wants the system to move through all the stages to avoid mistakes and ensure the rights of all suspects and defendants. If the man in the gym pled not guilty due to the reason of insanity, then he can ask for a jury trial to determine whether he is legally insane. The courts would then try the case and may present evidence to a jury, ultimately deciding hisfate.The goal is not to be quick, but to be thorough. Because the Bill of Rights protects the defendant’s rights, the criminal justice system should concentrate on those rights over the victim’s rights, which are not listed. Additionally,limiting police power would be seen as positive to prevent oppressing individuals and stepping on rights. The rules, procedures, and guidelines embedded in the Constitution should be the framework of the criminal justice system and controlling crime would be secondary. Guilt would get established on the facts and if the government legally followed the correct procedures. If the police searched the gym shooter's home without a warrant and took evidence then that evidence should be inadmissible, even if that means they cannot win the case. There are several pros and cons to both models; however, there are certain groups and individuals that side with one more often than the other. The notion that these models may fall along political lines is often based on previous court decisions, as well as campaign approaches in the U.S. The crime control model is used when promoting policies that allow the system to get tough, expand police powers, change sentencing practices such as creating “Three Strikes,”and more. The due process model may promote policies that require the system to focus on individual rights. These rights may include requiring police to inform people under arrest that they do not have to answer questions without an attorney (Miranda v. Arizona), providing all defendants with an attorney (Gideon v. Wainwright), or shutting down private prisons that often abuse the rights of inmates. To state that crime control is purely conservative and due process is purely liberal would be too simplistic, but it is relevant to recognize that the policies are a reflection of our current political climate. If Americans are fearful of crime, as Gallup polls suggest they are, politicians may propose policies that focus on controlling crime. However, if polls suggest police may have too many powers and that can lead to abuse, then politicians may propose policies that limit their powers such as requiring warrants to obtain drugs.Again, this may reflect society as a whole, a sector of society, or the interests of a political party or specific politician.	1,249	common-pile/libretexts_filtered	https://workforce.libretexts.org/Bookshelves/Corrections/Criminal_Court_Processes_and_Procedures_(Raber)/01%3A_Foundations_in_Criminal_Court/1.05%3A_The_Crime_Control_and_Due_Process_Models	libretexts	libretexts-0000.json.gz:43712	https://workforce.libretexts.org/Bookshelves/Corrections/Criminal_Court_Processes_and_Procedures_(Raber)/01%3A_Foundations_in_Criminal_Court/1.05%3A_The_Crime_Control_and_Due_Process_Models
LzmnjkbKRJzMX4Si	My X's	15 Here is a gap. The interview form replicates the role my father’s testimony played in the trial that eventually enabled you to rejoin your family in the United States. The surveillance files of the police state, the paranoia fueled by the Romanian dictatorship, and the silences in my own family carve themselves into the margins of my reading like cenotaphs. I can’t find a way to name what should be buried inside them. Nor can I figure out how to describe them. Yet I must move them out of the way in order to write clearly, to maintain the sort of vigorous[1] motion associated with critique. I don’t have a source for this image. I found it somewhere and saved it and now I’m not sure who to cite or attribute for its presence: A cenotaph is a memorial to an absence. Because the tomb is empty, it resembles the tomb of the risen Jesus Christ—a space vacated by the death it inscribes. Sometimes, I wonder if all the beings in cenotaphs were resurrected, or whether being resurrected is automatically implicated in existing as an unburied self. The writer cannot help unthinking the closure a cenotaph aims to secure. Whenever the writer discovers a memorial, or an effort to provide evidence of closure, the unthoughts appear in the margins as silences, absences, and traces. The poet may attempt to evoke them through images and music. The critic may announce them by arguing with the invisible, unnamed interlocutors. Each writer engages the unthoughts in their own way. The only writer one should not trust is the one who seeks the sort of power that comes from ignoring the unthoughts. I welcome the elliptical and the elusive as well as the graphics of mercilessness; there is no single style or avenue to the unthoughts. Beware of the gatekeepers who insist that such rules of style exist. Remember, the gatekeeper’s job is to keep things as they are, to maintain the existing order and the aesthetic of not disturbing the cenotaph. The gatekeeper is paid to distract us from wondering where the unburied went, and why language insists on banishing it. Do silences want libation? Does each silence need tipping?[2] Do I owe the silence an acknowledgment or a first drop in order to continue reviewing? If ghosts use silences to get our attention, then maybe talking about the silences enables the ghosts to feel seen. “Surely what the ghosts want is visibility and recognition,” I thought to myself as I dialed my father’s phone number for relief. Rigor refers to the quality of being extremely thorough, exhaustive, or accurate. Rigor mortis is the full-of-no-lifeness which is death. ↵ - Tupac Shakur acknowledged the ancient ritual of libation, or leaving the first drops to honor a local deity, in his song, "Pour Out a Little Liquor." "Tipping" or "pouring one" is a tradition that has met me in Alabama, where friends sometimes poured one for peers who died young, as well as Romania, where we tipped the ground with plum brandy to placate family ghosts. ↵	668	common-pile/pressbooks_filtered	https://una.pressbooks.pub/myxs/chapter/here-is-a-gap/	pressbooks	pressbooks-0000.json.gz:21312	https://una.pressbooks.pub/myxs/chapter/here-is-a-gap/
etSjsZ-Hk1jazsBC	Manual of general, descriptive, and pathological anatomy / by J.F. Meckel ; translated from the German into French, with additions and notes by A.J.L. Jourdan and G. Breschet, translated from the French, with notes by A. Sidney Doane.	OF THE PERIPHERY OF THE NERVOUS SYSTEM. § 1809. The periphery of the nervous system, comprehending the nerves properly so called, is divided into three sections : the nerves of the spinal marrow or the spinal nerves, the nerves of the brain or the encephalic nerves, and the ganglionnary or great sympathetic nerve. The number of these nerves, including the last, is forty-three pairs. But anatomists do not divide them in the same manner, for several cerebral nerves have been blended which are now considered as distinct pairs ; and farther, some consider as cerebral nerves those which others refer to the spinal pairs. We shall point out the differences arising from the first of these sources in our general remarks on the cerebral nerves. Those which arise from the second depend principally upon the division of the central mass of the nervous system. If the medulla oblongata be considered as the summit of the spinal marrow, we must naturally arrange the nerves arising from it among the spinal pairs ; hence their number is increased, while that of the cerebral pairs is diminished. DESCRIPTIVE ANATOMY. Thus Gordon admits only eight pairs of cerebral nerves and thirtyfour pairs of spinal nerves. Bichat makes three classes, the first comprising two nerves of the cerebrum, the second six of the mesocephalon, and the third thirty-four spinal nerves. Others with Portal, tacitly admit another intermediate class in which the accessory nerve is placed, which in the geneial method belongs to that of the cerebral nerves. Others as Sabatier, Bichat, and Cloquet, following Willis, exclude the first nerves of the spinal marrow from the number of spinal pairs, and consider them as the most inferior cerebral nerves. This last method is the least natural of all, for although the upper pair of the spinal nerves is often between the cerebral and spinal nerves in character, as may be seen from the description, still it is more like the latter than the former. The want of exactness in considering the last four cerebral nerves as the first spinal pairs, is also proved by the contradiction between the general characters of these four nerves and those of the spinal marrow, and it then becomes impossible to generalize about these last. This classification is farther very inconvenient, since a slight examination demonstrates that certain nerves (for instance, the auditory and external motor nerves) arise from the same region of the central part of the nervous system ; and with a little care and patience this may be proved of most of the others. The same reasons which impelled us to separate the medulla oblongata from the spinal marrow, and to consider it as a portion of the encephalon, have obliged us to place the nerves derived from it among the cerebral. The characters of these nerves, which resemble those of the cerebral rather than those of the spinal nerves, demonstrate also the superiority of our method. We shall first examine the spinal nerves, not only because we have already treated of the spinal marrow when describing the cervical part of the nervous system, but because from the cerebral nerves, which will be mentioned last, we shall naturally pass to the organs of sense, and from them to the more complex organs, with which we shall' close the treatise. NERVES OF THE SPINAL MARROW. § 1810. We have already mentioned the general characters of the nerves of the spinal marrow :(1) they are divided into as many sections as there are regions in the vertebral column, consequently into cervical , thoracic , lumbar , and sacral nerves. We shall first describe the thoracic nerves, except the first one, because they are more simple and arise the first ; next the nerves of the limbs, those of the inferior extremities arising from most of the sacral and lumbar nerves, those of the superior from the first dorsal and the last four cervical ; finally, the four superior cervical nerves, which lead by a remarkable transition to the cerebral nerves. Before describing minutely the nerves of these different regions, we ought to make known the following characters which belong to them in common, and which are important in regard to their topography. and those of the left sides. 2d. The nerves are not perfectly symmetrical ; one is often situated higher than another, and the number of cords is frequently greater by two or three on one side than on the other. But this difference is almost always compensated for, because then the adjacent pairs vary in the opposite manner. 3d. The upper and lower pairs are much nearer each other than the central. The latter also after the last dorsal nerve, are so near each other that they do not seem like separate nerves. They are also much nearer in the early periods of existence, and even during the first years of life, than at subsequent periods. This propinquity in the superior and inferior regions, is owing to the disproportion between the size of the nerves and the shortness of that part of the spinal marrow from whence they arise. Hence why the smaller thoracic nerves, which arise not much above the place from whence they leave the spinal marrow, are farther from each other, and the reason of the greater distance between the spinal nerves in animals whose necks are longer, and in whom too the spinal marrow descends lower than in man. 4th. The ganglions formed by the posterior roots are situated in the intervertebral foramina, except those of the sacral nerves which are found in the cavity of the sacrum. These ganglions are not all of the same size in all regions, and their development is not in a direct ratio with that of the nerves. In fact, a ganglion which is usually large, is not unfrequently replaced by another very small, and vice versa. The ganglions of the dorsal nerves are generally the largest, and those of the sacral nerves, especially the last, the smallest. 5th. All the spinal nerves divide soon after coming from the vertebral column into two branches, an anterior and a posterior, the first of which is often larger than the other, excepting always those of the second cervical nerve, which presents a contrary arrangement. The anterior branches turn first outward, then forward and inward, and terminate near or upon the anterior median line. The posterior go directly backward, and are distributed to the muscles which fill the groove between the spinous and transverse processes of the vertebra?, or in those which correspond to them in the cranium and the skin of this region. The first are distributed to the anterior muscles, which represent these dorsal muscles on the sides and anteriorly, and in those of the extremities. 6th. All the spinal nerves communicate together very constantly by one or several larger or smaller branches which they give off soon after leaving the vertebral canal, and which anastomose with those analogous. The anastomosing branches usually arise from the anterior part of the nerves, or belong only to their anterior branches, and go before the transverse processes on the sides of the bodies of the vertebræ. The brachial, lumbar, and sacral plexuses, are formed entirely in this manner ; their arrangement, however, differs from that usually seen, being more complex, since the anastomosing branches produce others winch anastomose several times with those near. Nerves composed of filaments from several trunks of different origins, arise from these points of union whether single or multiple. glions. Besides these anterior anastomosing branches which form along the vertebral column, a series of plexuses, corresponding in number to that of the vertebræ, the posterior branches also anastomose in an ana logous manner, especially at the upper region of the neck, although this arrangement is less general posteriorly than anteriorly. § 1811. The dorsal, thoracic, costal, or intercostal nerves (JV. tho racici, s. dorsales , s. costales , s. intercostales) are like the dorsal vertebræ, twelve in number. Some anatomists, however, as Haller,(l) count only eleven, and annex to the lumbar nerves that usually regarded as the twelfth. We shall examine only the eleven inferior nerves, as it is more convenient to describe the first with the four inferior cervical nerves. the superior sacral nerves. 2d. Most of them, especially the inferior, are those spinal nerves which arise farthest from each other. Still the superior are nearer to each other than the superior cervical nerves are. 3d. Most of them communicate only by intermediate filaments in the vertebral canal. Still we have often found between the first and second pairs, as between the second and third, a filament, proceeding obliquely from above downward, and from within outward, from the su- OF THE NERVOUS SYSTEM, perior edge of the inferior nerve to the inferior edge of the nerve situated immediately above. They have always seemed smaller between the second and third pair than between the first and second. 4th. Their trunk furnishes on emerging, and immediately after, some thin short branches which go forward and enter either into the nearest limiting ganglion of the ganglionnary nerve, or more rarely into the filament of communication between two of these adjacent ganglions. It then divides soon after emerging into two branches, one anterior , intercostal, or subcostal (R. intercostalis, s. subcostalis ), the other posterior or dorsal ( R . dorsalis ). The anterior branch proceeds under the rib, below which the trunk comes from the vertebral canal, between the external and internal intercostales muscles, and advances as far as these last extend. It accompanies the intercostal vessels lodged more or less immediately in the groove of the rib. In its course it gradually leaves the superior rib, so that its anterior part is nearer the rib below than that above. It then perforates the intercostales muscles near the sternum, and becomes external. Proceeding, it gives branches to these muscles, the upper part of the abdominal muscles, and to the skin which covers the intercostales muscles. These last filaments called the external thoracic nerves {R. pectorales externi ), successively perforate the intercostales muscles from behind forward, but all arise very far from the place where they emerge. Each anterior branch near its origin, sends off posteriorly several branches, of which the internal are usually numerous, and go, independently of those coming from the trunk, to the limiting ganglions of the ganglionnary nerve and their filaments of union, and anastomose in this place with the analogous branches of the adjacent dorsal nerves, while the external which are simple, pass on the internal face of the ribs, and communicate with those of the two adjacent dorsal nerves which go to meet them. These last are sometimes deficient in the middle pairs : but then absence is not always observed, as they not unfrequently occur there, although they are more developed in the upper and lower pairs. The posterior branch proceeds backward between the transverse processes of the vertebrae, between which it arises under the multifidus spinæ muscle, and there usually divides into external and internal branches, the latter of which are smaller and are deficient when the division does not take place. The internal branches are distributed to the multifidus spinæ, the semispinalis, the spinalis, the internal belly of the sacro-lumbalis, the digastricus nuchæ, the complexi, the transversalis, the inferior portion of the splenius, the rhomboidei, the trapezius, and the latissimus dorsi muscles. The external branches proceed outwardly, emerge between the scalenus muscle and the internal belly of the sacro-spinalis, and in this place penetrate between the two bellies of the latter muscle, to which they are distributed and also to the superficial muscles of the back. All the dorsal nerves are not of the same size. Except the first, which is the largest, they go on increasing in size much from the second to the last. However, they do not enlarge uniformly ; Haller(l) and Sœmmerring have observed, and the results of our numerous dissections also coincide with their opinion, that the the fourth, sixth, and eighth, are smaller than the fifth, seventh, and ninth. depend principally on their anterior or intercostal branches. The first is remarkably distinguished from the others. It soon goes upward and outward above the first rib, toward the brachial plexus, and opposite to this rib divides into two branches. One which is proportionally very small, goes forward and proceeds below the first rib like the anterior branches of the other thoracic nerves.. The second is much larger, and ascends and corresponds to the small anastomosing branches of the other thoracic nerves ; it immediately unites with the brachial plexus, with which we shall describe its farther progress. The anterior branches of the second and third' thoracic nerve, together furnish to the skin of the arm an inferior branch, which may be called the brachial nerve. Both then send some filaments to the intercostales muscles, penetrate the external, then descend to the integuments at the axilla and unite, but not always uniformly, with the internal cutaneous nerve of the arm, and expand in the superior and internal part of the integuments of the arm, so that their filaments, especially those of the second pair, descend to the elbow. Anteriorly, the anterior branches of these two nerves terminate in the anterior part of the pectoralis major and the triangularis sternqmuscle. In their passage they furnish no constant branches to the abdominal muscles. The anterior extremities of the anterior branches, and of the second, third, fourth, fifth, sixth, and seventh thoracic nerves, are distributed also in these two muscles, the skin of this region, and the thymus gland. The external pectoral twigs of these branches penetrate Into the upper part of the obliquus externus and rectus abdominis muscles, also in the skin which covers them. The anterior extremities of the anterior branches of the eighth, ninth, tenth, and eleventh thoracic pairs, pass above the costal digitations of the diaphragm, glide between the obliquus internus and transversalis abdominis muscles, distribute filaments to these muscles, and then go to the posterior face of the rectus muscle and to the skin which covers it. the diaphragm. The twelfth, described by Haller as the first lumbar nerve, anastomoses by a large branch with the first lumbar pair, and sends filaments to the diaphragm, then passes before the superior part of the quadratus lumborum muscle, between it and the posterior tendon of the transversalis, gives off filaments and divides at its external edge into superficial and deep abdominal branches. The former pass between the transversalis and obliquus internus abdominis muscles, and terminate there, and also in the lower part of the rectus and pyramidalis muscles. The second go between the two oblique muscles, pass through the external, and are distributed to the integuments of the abdomen as far as the ossa ilia. LUMBAR AND SACRAL NERVES. §1813. The description of the lumbar and sacral(\ ) nerves ought to follow that of the thoracic, because by then describing the cervical, we proceed from below upward to the explanation of the encephalic nerves. We shall combine our observations in regard to these two orders of spinal nerves, because they resemble each other in their most essential characters, and particularly as they unite to form the nerves of the inferior extremities. The five lumbar nerves and the sacral nerves, which are also five and sometimes six in number, arise near each other from the inferior prominence of the spinal marrow. They emerge from the medullary canal, the lumbar passing out through the intervertebral foramina, situated between the lumbar vertebrae as between the last one and the upper surface of the sacrum. The sacral nerves form the sacral foramina, except the last, which passes between the sacrum and the first piece of the coccyx. Not only the anterior and posterior roots of each pair, but the different pairs themselves are closely united to each other from their origin to the ganglions formed by their posterior branches ; but neither the first nor second communicate by intermediate filaments. The sacral nerves differ from all other spinal nerves by the situation of their ganglions, which do not anastomose when coming from the nerve, but in the channel of the vertebral column, and are as much more distant from the sacral foramina the lower the origins of the nerves to which they belong, so that the anterior and posterior roots of these last unite even within the medullary canal. The trunks resulting from their union divide near their origin, and also within the vertebral canal, into anterior and posterior branches, which do not usually anastomose together in this canal, hut emerge, the first through the anterior sacral foramina, the others through the posterior sacral foramina. The union of the anterior and posterior roots of the sacral nerves in the medullary canal, undoubtedly corresponds to the fusion of the false sacral vertebræ in a single bone, and it takes place after the same type so evident in the vascular system. Perhaps, also, it partially depends on the greater distance between the point from whence the nerves originate, and that whence they emerge. One circumstance favors this conjecture, viz. that the place where the posterior and anterior roots unite, is farther in the inferior nerves where the trunk is proportionally longer. But this circumstance also favors the opinion first proposed, since the inferior false sacral vertebrae unite also sooner than the superior. The anterior branches of these ten nerves which enlarge very much, form a plexus which may be called the femoral or crural plexus ( plexus femoralis). This plexus, like the brachial and cervical, is produced by the increase and multiplication of the anastomoses between the anterior branches, which is in proportion to the increase of volume of the nerves, and which takes place in breadth, and from without inward, and in thickness or from behind forward. We may consider separately the superior and inferior parts of this plexus, the first as the lumbar or lumbo-abdominal(l) plexus, the second as the sacral or sciatic plexus , since from each of these two parts, which are formed, the first by the lumbar, the second by the sacral nerves, arise nerves which are distributed differently. Still as the principal nerves which come from it are all distributed to the lower extremities, it is more convenient to regard them as forming one plexus only, as the inferior lumbar nerves mostly form the sacral plexus and the nerves which come from it. This plexus is indicated in the dorsal region by the much smaller anastomosis between the anterior branches, and which are constantly developed in the inferior thoracic pairs. from above downward, and the lower from below upward. The last two sacral nerves are the smallest, and the last especially is the smallest of all the spinal nerves. Next comes the first lumbar, then the third sacral ; the second lumbar is a little larger, being about the same size as the second sacral ; the third and fourth lumbar which are almost equal, are a little larger than the preceding. The fifth lumbar and the first sacral are much the largest. Dorsal branches which are much smaller arise from all these nerves which unite to form the crural plexus, commencing before the union of their anterior branches, when they emerge from the foramina : these go directly backward between the transverse processes of the lumbar vertebræ and the sacrum, passing there through the posterior sacral covers them. The posterior branches, the dorsal or lumbar (R. postici, s. dorsales , s. lumbales ), of the lumbar nerves diminish considerably in volume from the first to the last, so that the last two rarely extend to the skin, but are distributed only in the common belly of the sacro-lumbalis and multifidus spinæ muscles. From the first sacral nerve to the fourth, the posterior branches again enlarge much. That of the fourth is the largest ; the fifth is smaller, while the sixth is much more minute. § 1814. The anterior or abdominal branches {R. antici, s. abdcnninales ) of the lumbar nerves pass behind the psoas magnus muscle, unite not only with each other, but beside the first with the anterior branch of the last dorsal, the last with the anterior branch of the first sacral, to form the lumbar plexus, the lumbar ganglion of the ganglionnary nerve, and produce the nerves we are about to describe. The anterior branches of the sacral nerves, principally the first, second, third, and fourth, concur in the same manner to form the sacral plexus to which the fifth contributes least, and the sixth takes no part when it exists. Some ramifications arise from the anterior twigs after their union, some of which, the smaller ones, are usually formed by the filaments of a single nerve, while others which are larger, arise from the union of fasciculi from several nerves. The first are principally the external pudic nerve, several branches for the muscles in the lumbar region, the skin of this region and the common integuments of the inguinal region, the gluteal nerves and the inferior and middle hemorrhoidal nerves. § 1815. First and second lumbar nerve. From the first and second lumbar nerve, especially from the inferior extremity of the plexus between them, arises the external pudic or the genitocrural nerve (N. pudendus externus , s. spermaticus externus , s. inguinalis , s. genito-cruralis ), which passes between the superior digitations of the psoas muscle,arives at the anterior face of this muscle, on which it goesfrom behind forward and from above downward, and divides within the pelvis into branches which all emerge from the inguinal ring. Among these, the most considerable which are always the continuation of the trunk, arrive at the spermatic vessels, and are distributed in the male in the cremaster muscle and its coats, and in the female in the round ligament of the uterus, and anastomosing with the inferior pudic nerves, terminate in the glands and integuments of the inguinal region. The external passes under the crural arch, penetrates the aponeurosis, is dis- anastomoses with some filaments of the crural nerve. Besides there arise from the first lumbar nerve and its anastomosis with the second, branches designed for the psoas, the quadratus lumborum, and' the transversalis abdominis muscles, and for the integuments of the lumbar and inguinal regions. One of these branches, which is large, penetrates the psoas muscle, goes forward between the obliquus internus and transversalis along the crest of the ilium, and terminates in the inferior part of the large abdominal muscles and skin of this region and of the scrotum. Several filaments come from the second lumbar nerve and are distributed to the psoas and quadratus lumborum muscles and the skin of the lumbar and inguinal regions : usually there arise one or two distinct branches which are longer {nerfi lio-scrotal, Ch.), which passing through the psoas muscle, proceed outwardly before the quadratus lumborum, penetrate the transversalis, then the obliquus internus, to which they give filaments, go forward along the crest of the ilium, perforate the aponeurosis of the obliquus externus, and are distributed to the skin of the inguinal region and scrotum. 3d. The third lumbar nerve usually gives off a cutaneous nerve which unites to the preceding one or replaces it either partially or wholly, descends between the psoas and iliacus muscles, emerges from the pelvis, passing under the outward extremity of the crural arch and is distributed to the external and anterior extremities of the integuments of the thigh to the neighborhood of the knee. There it is the inferior branch of the crural plexus of Bichat, the inguino-cutané of Chaussier. iliacu3 muscle. 5th. The anterior branches of the fourth and fifth lumbar nerve unite to form a very considerable trunk, the lombo-sacral nerve of Bichat (JV. lumbo-sacralis ), which is much larger than the crural, and give origin in the very cavity of the small pelvis, but always before uniting with the first sacral nerve, to the superior gluteal nerve (JY. glutæus superior ), which emerges from the pelvis below the upper edge of the sciatic notch, is distributed to the gluteus médius and minimus, and penetrates even forward to the tensor vaginæ femoris. 6th. From the second and third sacral nerve, come some fasciculi which unite, then give filaments to the pyramidalis muscle, and coming from the pelvis below it, go to form the inferior gluteal nerve. Before these fasciculi, a very considerable nerve arises from these same nerves farther below and forward, sometimes also from the fourth sacral nerve, called the external common hemorrhoidal nerve (JY. pudendo-hœmorrhoidalis communis externus ), which re-enters into the pelvis, between the two sacro-sciatic ligaments, and divides into two branches, the external pudic , and the inferior hemorrhoidal nerve. branch of the ischium and the descending branch of the pubis, proceeding on gives branches to the obturator internus and bulbo-cavernosus muscles, then passes under the symphysis pubis to go forward, as the dorsal nerve of the penis (JY. dorsalis penis) in the male, and that of the nerve of the clitoris (JY. clitoridcus , s. pudendus superior) in the female, proceeds along the penis and clitoris, sends filaments to the skin which covers them, and also to the mons veneris and mucous membrane of the urethra, and terminates finally in the glans. The inferior hemorrhoidal nerve, called also the inferior pudic (JY. hœmorrhoideus, s. pudendus inferior ), partly accompanies the preceding, then goes upward between the bulbo- and ischio-cavernosus muscle, is distributed to the integuments and in all the muscles of the perineum to the inferior extremity of the rectum, the skin of the scrotum and mucous membrane of the urethra, and anastomoses with the external pudic, the inguinal and internal hemorrhoidal nerves. From the difference in size between the penis and clitoris, the external pudic is the larger of these two branches in the male, while the internal hemorrhoidal is the larger in the female. 7th. The third and the fourth sacral nerves also give off the middle hemorrhoidal nerves (JY. hcemorrhoidales medii), which are smaller, and not united at then- origin ; but this term is not exact for they are distributed partly to the rectum, the levator and sphincter ani muscles, and proceed on the side of this intestine to be distributed from below upward in the walls of the bladder, at the commencement of the urethra, uterus, and vagina, the prostate gland and vesiculæ séminales in the male, and frequently anastomose with the lower part of the great sympathetic nerve to give origin to the hypogastric plexus. 8th. The fifth and sixth lumbar nerves, when they exist, are in fact connected with the crural plexus, but do not contribute to form the nerves which come from them. Their anterior branches are distributed to the sacro-coccygeal, the levator, and sphincter ani muscles. Their posterior are distributed in the integuments of the posterior part of the anus and perineum. I. OBTURATOR NERVE. § 1816. The obturator nerve, sous-pubiofémoral, Ch. (JY. obturatorius),(l) the smallest of those belonging to this division, arises from the most anterior fasciculi of the second, third, and fourth lumbar nerves, rarely from the first, by an equal and sometimes greater number of roots, which meet at acute angles. It descends into the lower pelvis, before the following nerve, is covered by the psoas muscle, goes forward along the linea innominata, accompanied by the vessels of the same name, comes out through the obturator foramen, and divides into two branches, an anterior superficial and large and a posterior deeper and smaller. The anterior branch is distributed to the gracilis, the adductorlongus, and brevis muscles, and sends to the internal saphena nerve some branches which are sometimes so large that this last seems to arise from it rather than from the crural. The posterior branch is distributed in the obturator muscles, particularly the externus, and in the adductor magnus muscle, even descending to near its inferior extremity. II. CRUIiAL NERVE. § 1817. The crural nerve, férnoro-pré tibial , Ch. (JY. cruralis), is larger than the preceding, behind which it is situated, arises from the posterior part of the first, second, third, and fourth lumbar nerves, descends along the posterior and external side of the crural artery, between the psoas and iliacus muscles, gives several branches to these two muscles, but principally to the second, and furnishes one considerable which sometimes come off higher than the branches destined to the iliacus muscle, anastomoses near the crural arch with another branch which arises in this place, comes sometimes also from the fourth lumbar nerve, and then is distributed in the integuments of the anterior and internal face of the thigh. This branch is called the superior or the small saphena nerve (JY. saphenus superior , s. minor). A branch is generally given off a little below the crural arch which proceeds from within outward, and goes to the common lower extremity of the iliacus and psoas muscles. branches, an external larger, and an internal smaller, above. The external branch also soon divides into several twigs, which go to the four heads of the extensor of the leg, to the crurceus, and to the tensor vaginæ femoris muscle. These branches descend to the articulation of the knee and penetrate into its capsule. The internal branch gives to the sartorius muscle many twigs, most of which enter its middle and inferior part. It gives them also to the skin of the internal face of the thigh. But the largest of all the branches which come from it is the internal saphena nerve, tibio-cut ané, Ch. (JY. saphenus internus ). This nerve accompanies the internal saphena vein, which it surrounds at several different parts, distributes some filaments to the integuments of this region, descends on the back of the foot, and extends even to the great toe. § 1818. The sciatic nerve, grand femoro-poplité, Ch. (JY. ischiadicus),( 1) the largest of all the nerves, not only of the inferior members, but even of the whole body, arises from the inferior half of the fourth lumbar nerve, and from all the fifth, also from the three superior sacral ; the anterior branches unite to form the sciatic or sacral plexus ( plexus sacralis , s. ischiadicus ), which is only the inferior part of the crural plexus, although we usually consider this the only plexus of nerves of the lower extremities. § 1819. The sciatic nerve sometimes, partially or wholly, gives off the superior gluteal nerve and always the inferior either wholly or partially. This last emerges sometimes above and sometimes below the pyramidalis muscle, anastomoses with a branch of the sciatic nerve which arises a little lower, and is distributed with it in the gluteus maximus muscle. the sciatic notch, between the pyramidalis and gemelli muscles. There it sends to the obturator internus a considerable branch which penetrates from without inward between the large and small sciatic ligaments, and enters from below upward into this muscle. Then it gives a second, which descends before the gemelli and the tendon of the obturator internus, distributes filaments to the first two of these muscles, and is distributed in the quadratus femoris muscle. maximus muscle. The trunk first gives branches to the flexor muscles of the thigh ; then to the long head of the biceps ; then to the semitendinosus ; farther on, to the semimembranosus muscle ; finally, to the short head of the biceps. The filament of the semimembranosus is distributed also to the adductor magnus muscle. Farther on it gives off the middle posterior cutaneous nerve (JY. cutaneus posterior médius ), which descends under the skin of the posterior face of the thigh and leg to the calf, and anastomoses with some filaments of the superior and inferior nerves. The inferior posterior cutaneous nerve (JY. cutaneus posterior inferior) is given off below this branch ; it proceeds in part hke the former one, and is partially expanded hi the posterior part of the capsular ligament of the knee. § 1821. The sciatic nerve then divides into two branches : the internal, the larger, is the tibial nerve, and the external, the smaller, the peroneal nerve. This division usually takes place at the middle of the thigh, often higher up, and even above the sciatic tuberosity, so that the two branches are separated from each other by the pyramidalis muscle. the arrangement of the sciatic nerve in the mammalia. Rosenmuller mentions a national difference in regard to the height of this division, viz. that the sciatic nerves divide very high in the inhabitants of the north of Europe, while in those of the south it bifurcates very low not far from the ham.(l) We have not observed this difference. before it. The popliteal nerve (JV. popliteus ) rarely or never exists. (2) At most the name of the internal and the external popliteal nerve may be given to the upper part of the two terminating branches of the sciatic nerve, from their origin to the femoro-tibial articulation. a. Peroneal nerve. § 1822. The peroneal or external popliteal nerve (JV. peroneus ) often gives origin to the posterior, inferior, and middle cutaneous nerves. It descends from within outward on the internal side of the biceps femoris muscle, passes between the extensor longus digitorum communis and peroneus longus muscles, sends filaments to these muscles, and likewise to the tibialis anticus, and divides very high up into two branches, the superficial and the deep peroneal nerves. § 1823. The superficial peroneal , or the muscular cutaneous nerve, prétibio-digital , Ch. (JV. peroneus superficialis ), soon divides into two branches, an external superficial and small, the other internal, which is deeper and larger. The first, or the cutaneous peroneal nerve, which might more properly be called the middle cutaneous nerve of the back of the foot , or the external branch of the peroneal nerve (JV. cutaneus peroneus , s. cutaneus médius dorsi pedis, s. cutaneus peroneus externus ), descends on the peroneus brevis muscle, passes on the crucial ligaments of the tarsus, is distributed to the skin of the external part of the back of the foot, and terminates by filaments which are the tibial nerve of the little toe, the dorsal nerves of the fourth toe, and the peroneal nerve of the third toe. The second, the anterior nerve of the back of the foot (JV. dorsi pedis anticus communis, s. peroneus anticus, s. pedalis anticus), is situated before the former, also near the surface, and is distributed partly to the internal half of the back of the foot, partly to the skin of the external and anterior faces of the leg, and terminates by producing' the dorsal nerves of the two external toes and the peroneal nerve of the third. muscles on the anterior face of the tibia, at the side of the anterioi tibial artery, but does not pass with it from the posterior to the anterior face of the leg, between the two bones, for the whole trunk of the peroneal nerve is situated and divides on the external face of the fibula. Such at least is always the arrangement of the deep peroneal nerve according to our observations. Although we have made many careful dissections, yet we have never seen it pursue the course of the anterior tibial artery. Thus, although this authority is sanctioned by a great name,(l) it certainly is not the usual arrangement, and should be considered as a very rare anomaly, more especially as many writers, Coopmans(2) among others, do not sanction it, or speak only of the first. This nerve gives filaments to the peroneus longus, and to the extensor longus digitorum communis muscle, to the tibialis anticus, and to the extensor hallucis proprius, passes under the crucial ligament of the tarsus, and arrives on the back of the foot, where it terminates in the extensor digitorum brevis, the first interosseous muscle, and the internal part of the skin of this region, by anastomosing with some branches ofthe cutaneous nerve around the foot, so that the dorsal nerves of the large toe more properly arise from this than from the latter. We have always found the peroneal nerve distributed in this manner, but we have never found that of the two branches into which it divides at the upper extremity of the fibula, one was the external cutaneous nerve, the other, the common trunk of the anterior tibial and internal cutaneous nerves ;(3) Sabatier, (4) Coopmans,(5) andReil,(6) state the same distribution as ourselves : this arrangement then should be regarded as the most constant. § 1825. The tibial or internal •popliteal nerve (A', tibialis ), the largest and most internal of the two terminating branches of the sciatic nerve, may be called the popliteal ( JV. popliteus), from the bifurcation to the calf of the leg, although this term is not perfectly exact. It gives off first a considerable cutaneous nerve, the long posterior cutaneous nerve of the foot and the leg , or rather the external cutaneous tibial nerve of the foot { N . cutaneus longus posterior tibiae , s. cutaneus pedis externus , s. tibialis), which nevertheless often comes from the peroneal nerve, or at least especially when the sciatic nerve bifurcates high up> is partially replaced either by the posterior and inferior branch of this latter, or even by its inferior and middle cutaneous nerve. The external cutaneous tibial nerve of the foot descends behind the muscles of the foot, goes outward below the external malleolus, proceeds along the external edge of the foot and the fibular edge of the fifth toe, constituting its dorsal peroneal nerve, and proceeds to the top of it. The tibial nerve then gives off a small branch to the posterior part of the capsule of the articulation of the knee. This branch is sometimes given off higher or as high as the preceding. Farther on, the trunk of the tibial nerve gives external and internal branches to the three heads of the triceps, the plantaris, the popliteus, the tibialis posticus, and the flexor hallucis longus. § 1826. The tibial nerve then goes forward between the upper two heads of the triceps suræ muscle, descends between the tendo achillis, the tibialis posticus and the flexor hallucis longus, passes behind the malleolus internus, and goes to the sole of the foot. and two deep. § 1827. The superficial branch or the external tibial nerve (JV. tibialis exterior ), more properly the proper cutaneous plantar nerve (JV. cutaneus plantaris proprius ), is distributed to the skin below the malleolus internus, and at the posterior part of the sole of the foot. plantar nerve. The internal plantar nerve (JV. plantaris internus ) is usually a little larger and more superficial than the other ; it goes forward under the long head of the adductor hallucis, between it and the flexor communis digitorum brevis, and divides far back into two branches, an internal and an external: the latter is the larger. The internal branch having given filaments to the adductor hallucis, becomes the first plantar nerve of the toes ( N. . digitorum plantaris primus ), the tibio-plantar nerve or the internal nerve of the great toe (JV. plantaris internus , s. tibialis hullucis). internal side of the fourth. § 1829. The external plantar nerve (JV. plantaris externus ) goes forward and outward between the flexor communis digitorum brevis, and the tendon of the flexor longus, and divides before the tuberosity of the calcanéum into three branches. The internal branch, the fifth plantar nerve of the toes, which is entirely cutaneous, goes forward to the anterior extremity of the tarsus, where it divides into the plantar nerve of the fourth toe, and the internal plantar nerve of the fifth. The external branch, the musculo-cutaneous nerve, goes forward along the fibular edge of the sole of the foot, gives filaments to the abductor minimi digiti muscle, and becoming the external plantar nerve of the fifth toe, advances to its extremity, where as in the great toe, it receives at its external edge a distinct branch, an arrangement which is worthy of notice, as it contributes to the lateral symmetry. This nerve forms the sixth plantar nerve of the toes. The middle, deep, or muscular trunk is the largest. It goes obliquely inward and forward, penetrates between the tendons of the extensor longus digitorum communis and the deep muscles of the sole of the foot, and distributes itself in the lumbricales, the adductor and flexor hallucis muscles, and in almost all the internal part of the interossei muscles, and the small muscles of the fifth toe. § 1830. Till the time of Willis, eight cervical nerves, tracheliens Ch. (N. cervicales, s. N. colli)( 1) were admitted, but this anatomist and many after him, have mentioned only seven : as they consider the first cervical as the last encephalic nerve, an opinion less correct than the ancient. The general characters of these eight nerves are : 1st. Of all the spinal nerves they have the least extent in the vertebral column from their origin to the place where they penetrate the dura-mater, and emerge through the intervertebral foramina. 3d. The different pairs are united together by anastomoses ; these are usually simple, and extend from the inferior edge of the root of the superior nerve, to the upper edge of that of the lower nerve, and form the upper part of this last. The anastomosing filaments of the posterior roots are more constant than those of the anterior ; the latter usually exist only between the second and third pairs, and the third and fourth, and are deficient between all the others. On the contrary, the anastomosing filaments of the anterior roots exist in almost every part, but are sometimes deficient between the lower pairs. They are very seldom met with between the last cervical and the first dorsal nerve. We, however, should observe that the anastomosing filaments often do not exist between the middle cervical pairs, although found between the superior and the inferior nerves. The arrangement of these filaments is not always exactly the same ; we usually see a filament which goes a little obliquely upward and outward from the internal extremity of the upper edge of the lower nerve, towards the external extremity of the lower edge of the upper nerve. But sometimes this filament descends directly from the lower edge of the upper nerve, to the upper edge of the lower nerve. Between this arrangement and the preceding is one which is intermediate, where the most superior fasciculus of the lower nerve divides at its centre into two parts, the upper of which goes to the upper nerve in the first .of the two modes mentioned above, while the lower proceeds in the direction of the fasciculus, forming the most upper part of the lower nerve. Sometimes one or two thin fasciculi are found between two pairs of nerves, and usually a little nearer the lower than the upper. When there is only one fasciculus, this divides into two ; when two, they arise immediately one at the side of the other. In both cases either the fasciculi primitively distinct, or the two branches of the single fasciculus separate from below upward immediately after arising, and form, one the most inferior fasciculus, the other the most superior of the pairs between which they are situated. Sometimes they are united together by superior and inferior fasciculi, and afterward by a transverse filament. The first arrangement usually exists between the inferior cervical nerves, the third between the middle, the second between the superior, and the fourth between the first two, counting from above downward. The cervical nerves may be divided into two groups ; the first comprises the four lower pairs, the other the four upper pairs, for the first differ much from the second, as they enlarge to give origin to the nerves of the upper extremities. OF THE UPPER EXTREMITIES. § 1831. The nerves of the upper extremities ( JY . brachiales , s. extremitatis superior is) ( 1 ) arise from the first dorsal and the four inferior cervical nerves, which unite at some distance from their foramina to form the brachial plexus, so that a greater number of trunks comes afterward from the latter, each of which is formed from the fasciculi coming from several of the carrying nerves. The first dorsal nerve emerges below the first dorsal vertebra, the eighth cervical below the seventh cervical vertebra, the seventh below the sixth, the sixth below the fifth, and the fifth below the fourth. That nerve which usually occupies the centre of the group, that is the seventh cervical nerve, is the largest : the first dorsal and the fifth cervical nerves are the smallest : the fifth cervical nerve is smaller than the first dorsal, and the sixth and eighth dorsal are about the same size. The nerves which usually emerge from the brachial plexus are the thoracic , the scapular, the axillary, the radial, the external cutaneous, the median, the ulnar, and the internal cutaneous nerves. § 1832. Before uniting, the five nerves which form the brachial plexus give off much smaller posterior branches, which go to the deep dorsal muscles of this region. The brachial nerves are then only the enlarged anterior branches of the superior dorsal and the four inferior cervical nerves. § 1833. These anterior branches descend from within outward, pass between the scalenus anticus and médius muscles, and soon unite to form the brachial plexus ( plexus brachialis).{\ ) The two superior and two inferior usually unite before the middle with the adjacent branches. Two nerves arise from their union. The superior after passing several inches divides into two branches, one of which is the axillary or circumflex nerve, the other is large and unites with the large posterior fasciculi of the seventh and eighth cervical nerves to form the radial nerve. The inferior, having proceeded two or three inches, unites with one or two anterior fasciculi of the seventh cervical nerve, and thus produces a more or less complicated plexus,' whence the external cutaneous or the musculo-cutaneous nerve wholly, and the median partially arise. of which the second is larger. The posterior branch blends -with the upper posterior branch of the eighth cervical nerve in a small trunk, which soon joins the posterior branch of the trunk formed by the union of the fifth and sixth cervical nerves, and gives origin to the radial nerve. From the anterior branch and the common trunk formed by the union of the fifth and sixth cervical nerves, several anterior thoracic nerves arise and then the musculo-cutaneous nerve ; it gives rise with the eighth cervical and the first dorsal nerves to the median nerve. may be distinguished into posterior and anterior. The posterior arise from the branches of the fifth and sixth, sometimes also from the seventh cervical nerve, which are mostly united in a nerve which descends on the external face of the serratus major muscle, and is distributed in that muscle. The anterior arise from the anterior trunk formed by the union of the fifth and sixth cervical nerves, and also from the anterior branch of the seventh and eighth, descend from behind forward, and give filaments to the subclavius, the pectoralis major and minor muscles, the thymous gland, and the skin of the anterior and superior part of the chest and shoulder, where they anastomose with some filaments of the fourth cervical and axillary nerves. § 1835. The scapular nerve (JV. scapularis ), which is rather large often comes from the fifth cervical nerve before it joins with the following. When it arises only after the union, it commences almost in the place where it is, passes through the coracoid notch of the scapula, arrives thus on the posterior face of the scapula, sends filaments to the supraspinatus muscle, goes downward over the neck of the scapula, and arrives at the infraspinal fossa, where it is distributed to the infraspinatus and teres minor muscles. HI. AXILLARY NERVE. § 1836. The axillary nerve, scapulo-humeral , Ch. ( JV. axillaris , s. circumflexus brachii), or more properly the circumflex nerve, arises from the posterior and superior branch coming from the division of the common trunk formed by the union of the fifth and sixth cervical nerves. It first sends branches to the infraspinatus muscle, which often receives a large one from the common trunk mentioned above, it then gives some to the teres minor and major muscles, then passing between these two muscles and the long head of the triceps extensor, it is reflected outward and backward on the head of the humerus, expands in the deltoides muscle, and finally becoming the cutaneous nerve of the shoulder (JV. cutaneus humeri ), together with the fourth cervical nerve sends filaments to the integuments of this region. § 1837. The radial nerve, radio-digital, Ch. (JV. radialis), is much larger than the preceding, arises from fasciculi of all the brachial nerves by three branches, which come one from the seventh cervical nerve only, the second from the fifth and sixth, and the third from the eighth cervical and the first dorsal nerves. Soon after its origin, it gives a large branch to the latissimus dorsi and filaments to the triceps extensor muscles. A little below the middle of the arm it turns on the humerus, often reappearing on its anterior face between the brachialis intemus and the supinator longus muscles. In turning on the humerus it gives a long and thin cutaneous branch, the superior external cutaneous nerve (JV. cutaneus externus superior). This nerve descends along the radial edge and the inner face of the fore-arm, and interlaces with the cutaneous branch of the musculo-cutaneous nerve, extends a greater or less distance to the middle of the fore-arm, to the carpus, and even the thumb. The trunk of the radial nerve then gives branches to the supinator longus and the extensor carpi longus radialis muscles. It divides at the lower extremity of the fore-arm into two branches, a superficial or cutaneous and a deep or muscular. The superficial branch (R. superficialis dorsalis, s. cutaneus) descends along the anterior edge of the radius between the supinator longus and the radiales muscles, arrives at the outer face of the forearm, passing below the tendons of the first of these three muscles, and divides usually some inches below the inferior extremity of the fore-arm into two almost equal branches, the anterior being a little the larger, which distribute filaments to the anterior region of the integuments of the back of the hand, and to the dorsal face of the three anterior fingers. The anterior branch anastomoses in several places with'those of the cutaneous branch of the musculo-cutaneous nerve, sends filaments to the skin of the radial side of the carpus and metacarpus, and divides on the carpus into two small branches, the clo7'sal «erres ofi the thumb (JV. cutanei pollicis dorsales), which descend on its dorsal side along the radial and ulnar edges to its anterior extremity, furnish filaments to its dorsal face, and anastomose together and with the palmar nerves of the thumb. principal ramuscules, an anterior and posterior. The anterior goes to the skin between the thumb and index finger, and arrived at the radial side of the last finger becomes the radiodorsal nerve of the index finger (JV. dorsalis radialis indicus). The posterior soon subdivides into two filaments, one of which produces the cubito-dorsal nerve of the index finger and the radio-dorsal nerve of the middle finger, while the second is the cubito-dorsal nerve of the middle finger. All these ramifications frequently anastomose with each other or with those of the ulnar nerve, and thus give rise to a plexus called the dorsal arch of the hand ( rete , s. arcus dorsalis manus ). The deeper or larger muscular branch gives off branches for the radialis brevis and the supinator brevis muscles ; it then turns over these muscles and engages itself between their fibres, penetrates between the extensor digitorum communis muscle, arrives at the posterior surface of the fore-arm, gives off some large branches, some of which are recurrent to the extensor digitorum communis, to the extensor minimi digiti, and to the ulnaris internus and externus muscles. Then as the external interosseus nerve ( JY. interosseous externus), it descends on the extensor and the adductor pollicis longus muscles, to which it sends filaments, as also to the extensor indicis proprius muscle, and is finally lost in the capsule of the wrist-joint. V. EXTERNAL CUTANEOUS NERVE. § 1838. The external cutaneous nerve, or muscido-cutaneous nerve, or the perforating nerve of Casserius, radio-cutané , Ch. (JY. cutaneus externus, s. musculo-cutaneus, s. perforons Casserii), is much smaller than the preceding, although it descends almost as low as it. It arises from the fasciculi of the fifth, sixth, and seventh cervical nerves. It sometimes comes from the median nerve. It frequently but not always penetrates the coraco-brachialis muscle. When this is not the case, it passes on the internal edge of this muscle, being joined to it only at its surface. It divides high up in the arm into two branches, the one muscular and small, the other cutaneous and larger. muscle. The cutaneous branch passing between the biceps and the brachialis internus muscle, arrives at the anterior edge of the arm, descends on the radial side in the aponeurosis,' accompanying the cephalic vein. It anastomoses frequently above with the external cutaneous nerve, and below with the dorsal branch of the radial nerve ; it is distributed to the skin of the posterior surface of the fore-arm and the hand, and terminates at the thumb. VI. MEDIAN NERVE. § 1839. The median nerve, mcdio-digital , Ch. (JY. mcdianus ), the largest nerve of the upper extremity, comes also from the brachial plexus. It descends on the inside of the arm near its lower extremity without giving off any branch, unless it be sometimes the external cuianeous nerve. Some inches below the elbow-joint it gives several small muscular branches to the pronator teres, to the upper part of the radialis internus, the palmaris longus, and to the upper part of the flexor digitorum brevis muscles. Near the elbow it gives off a considerable branch, the internal interrosseus nerve (N. interrosseus internus ), which descends before the flexor communis digitorum profundus, distributes branches to this muscle and to the flexor pollicis longus, is reflected on the anterior edge of the pronator quadratus, arrived thus at the posterior face of the fore-arm, it terminates in this muscle. The trunk descends before the flexor digitorum profundus, between the bones of the fore-arm, gives off filaments to this muscle and to the palmaris longus, and gives a cutaneous branch which is distributed in the integuments of the palmar face of the carpus, where it anastomoses with the branches of the musculo-cutaneous nerve and the ulnar nerve. It then divides near the lower third of the fore-arm into two branches, an anterior or radial and a posterior or ulnar ; the first is the larger. These branches descend without giving any twig to the fore-arm between the tendons of the flexors, with which they pass under the ligaments of the carpus, where they usually unite by some transverse fibres. At the palm of the hand they separate. The anterior very soon divides into three filaments, the radio-palmar and the cubito-palmar nerves of the thumb, and the radio-palmar nerve of the index finger , these frequently anastomose together, extend to the extremities of these two fingers, and terminate by considerable branches, and give filaments to the first lumbiicalis muscle. The posterior then sends a large branch to the adductor brevis, to its opponens muscle and the flexor pollicis brevis, after which it becomes the cubito-palmar nerve of the index finger. The posterior which is larger sends filaments to the integuments of the hand, soon divides into two ramuscules, the cubito-palmar nerve of the third finger and the radio-palmar nerve of the fourth. VII. ULNAE OR CUBITAL NERVE. § 1841. The ulnar nerve,- cubito-digital ( JY . ulnar is. s. cubitalis), is a little smaller than the preceding, and arises from the three inferior nerves of the brachial plexus. It descends inward and backward, gives off no branches along the arm except sometimes the internal cutaneous nerve, and arrives at the ulnar side of the fore-arm, passing imme- easily compressed. Arrived at the fore-arm, it first gives off ramifications to the flexor digitorum profundus and to the flexor carpi ulnaris, and then sends under the skin along the basilic vein a small branch, called the long palmar nerve (JV. ulnaris longus palmaris), which anastomoses in the carpus with an analogous branch coming from the median nerve ; about the middle of the fore-arm, it divides into two branches, a dorsal and a palmar. The dorsal branch (JV. ulnaris dorsalis ) passes between the ulna and the tendon of the flexor carpi ulnaris muscle, comes on the back of the fore-arm, where it subdivides into two twigs. The anterior or the radial also soon divides into two principal filaments, one of which is the radio-dorsal nerve of the fifth finger and the cubito-dorsal nerve of the fourth , the other is the radio-dorsal nerve of the fourth finger. nerve. The palmar branch ( JV. ulnaris palmaris ) which is larger, descends between the tendons of the ulnaris internus and the flexor digitorum communis muscles, and divides on the ulnar edge of the carpus into a superficial and a deep twig. The deep or muscular twig goes downward and forward between the adductor and flexor minimi digiti muscles, passes across to the radial side of the hand, going between the tendons of the flexor communis and interossei muscles, and sends numerous twigs to the muscles of the little finger, to the interossei and lumbricales, and to the adductor pollicis muscles. The superficial or cutaneous branch is smaller than the preceding, anastomoses by one or several filaments with the cubito-palmar branch of the median nerve (from this union we have a superficial palmar arch), and soon divides into two filaments, an anterior and a posterior. The anterior soon divides into the cubito-palmar nerve of the fifth finger and the common trunk of the cubito-palmar nerve of the fourth , and the radio palmar nerve of the fifth. Each finger receives two palmar and two dorsal branches, the first of which are the largest. They proceed along the radial and ulnar edges of the finger directly at the side of the digito-palmar artery, more inward and downward than it, that is, nearer the palmar face, as likewise the superficial palmar arch is nearer the surface than their trunk. They go to the extremity of the fingers. In this passage they give off several large branches, distribute some small twigs to the palmar face of the finger, when they anastomose with each other. § 1842. The internal cutuneous nerve, cubito-cutané, Ch. (JV. cutaneus internus ), usually arises from the first dorsal by several roots ; it sometimes though rarely comes from the ulnar, being the first branch. It descends directly below the skin at the side of the basilic vein in the arm. From its upper part arises the superior cutaneous nerve (A’. cutaneus internus superior ), which sometimes comes from the ulnar nerve, and is distributed to the triceps extensor muscle and the skin which covers it. A little lower it gives off the inferior internal cutaneous nerve (A. cutaneus internus inferior ), which distributes its branches to the lower part of the triceps extensor muscle, to the skin of the elbow, to the integuments of the ulnar edge of the fore-arm, and to the carpus, and which terminates on the cubital edge of the hand and little finger, descending along the basilic vein, and anastomosing with the branches of the ulnar nerve, which it meets in its course. In the whole course of this nerve its different branches anastomose frequently with each other and with those of the external cutaneous nerve on the posterior side of the fore-arm. § 1843. The four superior cervical nerves are smaller than the inferior. Like the latter their size increases progressively from above downward, so that the second and third are the largest. They form with the lower ones an uninterrupted series ; and like them their anterior branches immediately after their trunks have come from the intervertebral foramina, give off twigs which anastomose with the adjacent branches and form the cervical plexus , trachélo-sous-cutané, Ch. ( plexus cervicalis). This plexus descends along the corresponding vertebrae, below the sterno-cleido-mastoideus muscle, outside of the internal jugular vein, carotid artery, and pneumogastric nerve, on the scalenus posticus muscle. It anastomoses below with the brachial plexus, within with the superior and middle cervical ganglions of the great sympathetic nerve. We have as much reason to think the different branches of the cervical nerves are derived from them as that they arise from the cervical pairs themselves. Some modern anatomists, among whom are Bichat(l) and Cloquet,(2) have adopted this method, and describe separately only the posterior branches and the commencement of the anterior, and consider the cervical plexus as the origin of all the nerves which arise after the union of the anterior branches. But we shall not follow them, as the which are not seen in the other plexiform nerves of the spinal marrow. The diaphragmatic nerve is the only one to be considered separately, because produced not only by several pairs of the cervical plexus but also of the brachial plexus, so that it seems to belong in common to the superior and inferior section of the cervical nerves. I. DIAPHRAGMATIC NERVE. § 1844. The diaphragmatic or phrenic nerve (JV. diaphragmations, s. phrenicus){l ) arises by several branches from the lower extremity of the brachial plexus. The largest branch is always furnished by the anterior branch of the fourth pair, but a smaller one always arises from the third and often from the second, and about three from the brachial plexus. This nerve sometimes joins the ascending branch of the hypoglossal nerve. The diaphragmatic nerve descends on the side of the neck between the rectus capitis anticus and the scalenus muscle, gives branches to these muscles and to the thymous gland, anastomoses by a few filaments with the inferior and middle cervical ganglions of the great sympathetic nerve, enters the chest between the subclavian artery and vein, then goes forward, descends before the pulmonary vessels, and lastly passes between the internal wall of the external sac of the pleura and the pericardium, applied very exactly to the surface of this last membrane, and is finally distributed to the diaphragm. A little before arriving at this muscle, it divides into several branches which are united by intermediate filaments, some of which go to the convex face of the diaphragm and others pass through its costal portion and its central tendon, accompany the ascending vena-cava on the right, with which they emerge through the foramen quadratum, come into the abdomen, where they not only expand on the inferior face of the muscle, but also anastomose by several filaments with the solar plexus of the great sympathetic and with the gastric branch of the pneumo-gastric nerve. These anastomotic filaments almost always project at intervals, and these projections often form real ganglions. The left diaphragmatic nerve is situated farther back, and is longer than the right, as it turns around on the summit of the heart. Besides the filaments it gives to the diaphragm, it sends some also to the lower part of the esophagus. It. FOURTH CERVICAL NERVE. § 1845. The fourth cervical nerve(l) is a little smaller than the two adjacent. It emerges through the third intervertebral foramen, between the anterior and posterior intertransversarii muscles, and immediately divides into an anterior and a posterior branch. The posterior is the smaller and deeper : it anastomoses with a branch of the third cervical nerve, gives a twig to the complexus muscle, passes transversely between this muscle and the semispinalis colli, to which also it sends large filaments, also to the multifidus spinæ, then penetrates between the complexus and trapezius muscles, and expands in the corresponding skin of the neck. The anterior branch, which is the larger, first gives off a filament to the rectus capitis major anticus muscle : then it sends one of anastomosis to the cervical portion of the great sympathetic nerve, or to its superior cervical ganglion. It usually gives off also a twig to the descending branch of the hypoglossal nerve, and constantly sends filaments to the levator anguli scapulæ muscle. It then sends an ascending anastomotic twig to the anterior branch of the third cervical, and forms with it the third cervical nervous plexus , then divides into three or four twigs which also proceed from above downward, and are called the supraclavicular nerves (JY. supra-claviculares). The latter are distributed principally to the skin which covers the clavicle and the shoulder. The anterior (JY. supra-clavicidares anteriores ) are distributed to the skin which covers the first piece of the sternum and the sternal extremity of the clavicle to the mamma, anastomose with the anterior thoracic nerves coming from the fifth cervical, and send filaments also to the subclavius muscle. The middle (JY. supra-clavicidares medii ) are distributed to the trapezius muscle and the posterior belly of the omo-hyoideus muscle, and also to the skin which covers the body of the clavicle, its scapular extremity, and the scapula. the neck and of the shoulder. A small ascending branch generally arises from the anterior or the middle nerve ; this forms a very broad plexus by anastomosing with the middle subcutaneous cervical nerve, which comes from the third pair. partly in the skin, and partly in the trapezius muscle. (1) G. F. Peipers, Diss. sistens tertii et quarti nervorum cervicalium descriptionem , cut accedit succincta eorundcm nervorum quinti , nervi phrenici , prœsertim ratione originis nervi duri ejusque prœsertim rami inferioris , nervi hypoglossi et occipitalis maximi a secundo cervicalium nervo adumbratio, Halle, 1793. § 1S46. The third cervical nerve( 1) is larger than the preceding. It emerges from the spinal canal between the second and the third cervical vertebne, and divides into two branches, a posterior and an anterior. The posterior branch is much smaller than the anterior ; it proceeds from before backward between the anterior and posterior intertransversarii muscles, gives filaments to these two muscles and also to the transversalis colli and the complexus minor muscles, goes backward passing on this latter, sends anastomosing filaments to the posterior branch of the second and third cervical nerves, and also to the small occipital nerve which comes from the anterior branch of the third pair, glides below the biventer cervicis nuchæ and the complexus major muscles, which receive considerable filaments from it, and goes directly to the trapezius muscle in which it is distributed, and also in the middle region of the skin of the neck. The anterior branch sends first small twigs to the rectus capitis major anticus and to the longus colli muscles, then proceeds from above downward and divides into two branches, a descending and an ascending. The descending branch, the superficial cervical nerve, the submental nerve, Ch. ( JV. superficialis colli, s. profundus, JV. sub-cutaneus colli médius) turns on the posterior edge of the sternocleido-mastoideus muscle, to go to the outer face of this muscle, to which it gives filaments, sends others which anastomose with the ascending branch, and terminates first, by descending ramifications called the middle and inferior subcutaneous cervical nerves ( JV. subcutanei colli medii et inferiores), in the middle and lower part of the skin of the neck ; second, by ascending twigs which anastomose fiequently, both with each other and with the final twigs of the facial nerve in the skin which covers the ascending and horizontal branches of the lower jaw from the lobe of the ear to the chin, and thus form the superior subcutaneous cervical nerves (JV. subcidanei colli superiores). The highest and most posterior portion of this descending branch, or the great auricidar nerve, the zygomato-auricular nerve, Ch. (JV. auricularis magnus , s. cervicalis), goes directly upward, and passing behind the ascending branch of the lower jaw arrives at the external ear. Its ramifications are distributed from behind forward and from below upward in the integuments and posterior muscles of the external ear, and also in the skin of the auditory foramen. The uscending branch goes backward and upward, gives off first an ascending anastomosing filament which unites to a descending filament of the third pair to form the second cervical nervous plexus, and often sends off immediately the great auricular nerve. In this case its pos- tenor part, and when the great auricular nerve comes from the descending branch, its entire trunk becomes the small or the anterior occipital nerve (JV. occipitalis minor, s. anterior ), which most generally soon divides into several filaments, ascends on the complexus minor and splenius capitis muscles and expands in the skin of the occiput, in that of the mastoid process, in that of the posterior and superior part of the external ear between the superior and posterior auricular muscles, farther forward than the large occipital nerve given off by the second cervical pair, although anastomosing frequently with this latter, as with the filaments of the facial nerve. § 1847. The second cervical nerve(l) emerges from the spinal canal between the first and second cervical vertebra. It is larger than the third, and divides into an anterior and a posterior branch, directly below the ganglion. The posterior branch, the great occipital nerve (JV. occipitalis maximus ), is much larger than the anterior, which is contrary to the arrangement of the inferior cervical nerves except the first, and to that of all the other spinal nerves. It goes directly backward below the complexus minor muscle, first sends, filaments to the obliquus capitis inferior muscle, gives off others which pass on this muscle to anastomose with the first and third cervical nerves, also gives them to the upper part of the two splenii muscles, to the biventer cervicis, the complexus and trapezius muscles under which it proceeds, to the multifidus spinse and to the skin of the neck, approaches the median line, and arrives at the occipital bone ; it there forms most of the nerves in this region, ramifies to the lambdoidal suture, where its filaments expand in the skin and occipitalis muscle, and anastomose with those of the facial and small occipital nerve. The anterior branch is smaller than the preceding ; it goes forward and outward under the obliquus capitis superior muscle, and soon divides into two anastomotic branches, a superior, ascending (JV'. anasto moticus adscendens ), and an inferior, descending (JV'. anastomoticns descendais), which unite, the first with the anterior branch of the first cervical nerve, to form the first cervical nervous plexus ; the other with the anterior branch of the third, to form the second cervical nervous 'plexus. From the upper branch arise filaments which enter the superior cervical ganglion of the great sympathetic, the sublingual, and the pneumo-gastric nerve : one arises even from the bifurcation and goes into the superior cervical ganglion ; finally the inferior branch produces one which is larger, which descends from behind forward and anastomoses with a similar twig from the anterior branch of the third cervical nerve, and with the descending branch of the sublingual nerve. § 1848. The first cervical nerve, called also the suboccipital or the tenth encephalic nerve (JV. cervicalis primus , s. supremus, s. occipitalis , s. infra-occipitalis, s. decimus cerebri), (1) is frequently the smallest of all the spinal nerves, since it is not unfrequently smaller than the last sacral nerve ; at least it is always smaller than the other nerves of the spinal marrow, except the last. By its situation, origin, and direction, it makes the transition from the spinal to the encephalic nerves, for it frequently in the same and still more so in different subjects resembles the former in some characters, the latter in others. Hence for a long time, that is, since Willis lived, it has been considered as an encephalic nerve, the tenth cerebral nerve. It is not till lately that it has been generally admitted among the spinal nerves, to which it is more similar than to the cerebral nerves. cervical vertebra. Very often, perhaps even most generally, although Huber considers the existence of two roots as a constant fact, (2) it arises by one anterior root which, like that of the sublingual nerve, comes from the anterior cord of the spinal marrow. (3) Even when a posterior root exists, the anterior is much larger than it, and is composed of from two or three to seven fasciculi, rarely of eight, more commonly of two or three. These fasciculi, situated one above another, are also formed of smaller filaments. The posterior root presents only from one to three, and rarely four filaments which are much smaller, the inferior of which, a remarkable fact, is generally much larger than the others : these filaments commonly unite in two fasciculi which proceed the superior outward, the inferior upward. Even when the posterior root exists, the nerve however is most generally formed anteriorly by but one root, the anterior, for the latter ascends more than the posterior. The posterior root is generally situated behind the accessory nerve ; sometimes, however, but very rarely (we have never observed it), it passes before. It is then in this latter case unusually near the anterior, although the ligamentum centiculatum even then always separates it from them. Farther it is constantly nearer the anterior face than are the posterior roots of the other spinal nerves. (3) Morgagni (Ep. anat., vol. xvi. 8vo.) also says : Septies ab eo tempore ex quo semel anteriores tantam reperi, posteriores illas fibr as quœsivi. Bis dubius hœsi. Q uater procvl omni dubio nullas omnino fuisse deprehendi. Semel a dextris.... sed ne in eo quidem ipso.... ullam prorsus fibram e sinistris. — See also Vicq-d’Azyr, Mém. de Paris, 1781, p. 596. — Gordon, p. 214. — Cloquet, p. 631. The posterior root most generally anastomoses with the accessory nerve. This is sometimes, although more rarely, the case with the anterior. Sometimes the posterior does not unite with the anterior ; it goes only to the accessory nerve, in which case the latter after forming a small ganglion which however does not constantly exist, sends one or two filaments to the anterior root of the second cervical nerve. Sometimes instead of the posterior root we find only a plexus which anastomoses with the accessory nerve, the filaments of which go towards the opening destined for the passage of the first cervical nerve.(l). When the posterior root and the accessory nerve do not anastomose, we generally find a filament which extends from this root to the posterior root of the second cervical nerve ; but this filament is not constant. The direction of the first cervical nerve is most generally transverse from its origin to its emerging from the spinal canal. It not unfrequently proceeds in a direction opposite to that of the other cervical nerves, that is, it proceeds a little more from below upward and from within outward like the cerebral nerves. The superior filaments of the posterior root rarely go upward, and the inferior downward. Still more rarely the inferior filaments of the two roots have a direction from above downward, while on the contrary the superior commonly follow this direction. It is easy to observe that the smallness, the frequent absence and the anterior situation of the posterior root, its separation from the anterior, the anastomosis of the latter with the accessory or the second cervical nerve, and the direction of the whole nerve, establish a great analogy between the latter and the cerebral nerves, while the frequent existence also of the roots and their place of origin, establish a resemblance with the spinal nerves. § 1849. The trunk of the first cervical nerve passes between the occipital portion of the basilar bone and the transverse process of the atlas, in the lateral groove of the vertebra below the vertebral artery, after forming a very elongated, more or less apparent, and often almost imperceptible ganglion. It divides, as usual, opposite the posterior edge of the atlas into an anterior and a posterior branch. The posterior is larger, and proceeds obliquely backward and upward, and divides into seven or eight radiating filaments which go to the obliquus capitis minor, the obliquus capitis major, the rectus capitis major and minor, and the complexus muscles. Some penetrate within the mastoid process. The anterior is smaller, goes first from behind forward along the vertebral artery to the place where this vessel leaves the vertebral canal, it then immediately ascends between the transverse process of branches. The first turns around on the transverse process of the atlas, proceeding from above downward, and anastomoses with one or two ascending filaments of the anterior branch of the second pair. It gives off some filaments which unite with the pneumo-gastric, the hypoglossal, and the great sympathetic nerve. minor muscles. The peculiarity in the distribution of this nerve, is, that being situated very deeply, it sends off filaments only to these muscles and these vessels, and does not extend to the skin. But of all these characters only the first is with difficulty of general application. The fifth pair is an exception to the second, as its semilunar ganglion is formed without the concurrence of any other nerve : we can even to a certain extent mention the olfactory nerve in this respect. The glosso-pharyngeal and the pneumo-gastric with the accessory nerve, also produce a considerable ganglion shortly after leaving the cranium. In fact , these latter unite to give rise to the ganglion : but first, the anomaty resulting from it disappears, when it is considered that these three nerves should be regarded as forming but one : second, almost all the cervical nerves anastomose with each (1) J. D. Santorini, Obs. anat ., cap. iii. — A. Bergen, Dé nereis quibusdam cranii ad novem paria hactenus nun rélalis, Erfort, 1738.' — Morgagni, Ep. anal., xvi. — Sœmmerring, De basi cncephali et originibus nervorum e cranio egredienlium , Gottingen, 1778.— Id., Tabula baseos encepliali , Francfort, 1799. — Stieck, De quinque prioribus encepliali nereis , Gottingen, 1791. other within the dura-mater by intermediate filaments, before that each produces its ganglion. As to the third character, it does not depend on the nerves, but only on the difference in the size and connections of the bones of the skull and the vertebrae. Besides, it is not so exclusive as has been asserted, since we not only sometimes find an opening in the first cervical vertebra for the first cervical nerve, but also the sacral nerves constantly pass through the foramina of a bone originally composed of several pieces immoveably articulated together. In animals we find foramina for the passage of the corresponding cervical nerves, not only in the first cervical vertebra, in all the mammalia except some apes, but also in the second, but even in several of the following in some of these animals, particularly the hog. The insufficiency of the latter character seems no less evident when we consider, first, that the spinal nerves necessarily cannot go to parts which are not yet formed : second, that the lumbar and sacral nerves are distributed to the genital and urinary organs, and also to the latter portion of the intestinal canal. It follows then that the distinction between the spinal and the encephalic nerves is not so well marked as we should be tempted to think at first view, and from the assertions of anatomists. Far from it : we shall demonstrate that it is very easy to refer the second to the first, and to show that they are both constructed after the same type. § 1851. We have already mentioned the principal differences in authors in respect to the number of the encephalic pairs they establish, and demonstrated that they depend on the different manner of bounding the different portions of the centre of the nervous system. But there are others depending on the fact, that some cerebral nerves have been regarded sometimes as distinct pairs, sometimes only as portions of pairs. . The old anatomists followed the first course, while the moderns, adopting the second, have increased the number of cerebral pairs, which has gradually risen from seven to twelve, and even according to Malacarne,(l) to fifteen.(2) The twelve cerebral nerves most generally admitted now, are, proceeding from behind forward, 1st, the sublingual ; 2d, the accessory ; 3d, the pneumo- gastric ; 4th, the glosso-pharyngœal ; 5th, the facial ; 6th, the auditory ; 7th, the external or posterior motor ; 8th, the trifacial : 9th, the internal or superior motor ; 10th, the common motor ; 11th, the optic ; 12th, the olfactory nerve. The reasons for admitting a smaller number of nerves are, first, the olfactory nerve was long considered, till the time of Massa, not as a nerve, but as a portion of the cerebrum : second, till the time of Achillini, the common external motor nerve of the eye was considered as part of the fifth : third, the auditory and the facial nerves have been considered as one till the time of Sœmmeriing ; fourth and fifth, till the time of Andersch, the glosso-pharyngceal and the accessorynerves have been considered only as portions of the pneumo-gastric nerve. Certain anatomists, however, and even before the preceding division was established by Scemmerring’s publication, had considered a greater or less number of the nerves mentioned, as distinct pairs. Malacarne states the number of the encephalic nerves to be fifteen : first and second, by admitting an accessory nerve to the common motor and to the superior motor nerve ; third and fourth, by considering the three branches of the trifacial as so many distinct nerves, which would make sixteen pairs, if instead of distinguishing the glosso-pharyngceal, it had not been united to the pneumo-gastric nerve. But this method is very objectionable, for even when Malacarne had cause to admit his accessory nerves to the motors, he could regard them only as the roots of these latter, to the trunks of which they unite : second, the three branches of the trifacial nerve arise by a common nervous trunk : third, the glosso-pharyngceal nerve deserves to be separated from the adjacent nerves, and considered as a distinct pair more than any which Malacarne insulates. Farther, we shall have occasion hereafter to show that it would be more convenient to diminish than to increase the number of cerebral nerves, but at present we shall follow the common division. The principle of the nomenclature of the nerves is not the same in all. Formerly the respective situation of their origin was taken for them, and they were numbered from before backward. Still later this method was preserved, but names drawn from their distribution and their uses were applied. This latter mode is undoubtedly the best, and we follow it much more willingly, because the first does not entirely agree with our mode of considering the nerves, commencing at the spinal marrow. volume, form, and origin. 1st. Volume. The cerebral nerves generally diminish in size in the following older;, the trifacial, the optic, the olfactory, the auditory, the common motor, the pneumo-gastric, the glosso-pharyngceal, the facial, the external motor, the accessory, the hypoglossal, and the superior motor. however is slightly flattened, and the olfactory is triangular. 2d. Texture. Almost all are fibrous from their origin ; in the olfactory nerve alone there are no distinct fibres. In some, the fibres continue separate longer than in others, and they are the more so, the more posterior the origin of the nerves. They generally unite in fasciculi of various sizes before they blend in one trunk. These fasciculi are more numorous, and are more similar in size the more posteriorly the nerves are situated. The two anterior nerves form only one trunk on leaving the cerebrum. We must mention here the differences in their substance and solidity. The eleven posterior cerebral nerves are composed, like the spinal nerves, of white substance ; the olfactory, on the contrary, contains some which is gray. This nerve and the auditory are much softer than the others. a. The cerebral nerves succeed each other from behind forward. b. All arise from the inferior part of the cerebrum. Some, particularly the hypoglossal, the accessory, the pneumo-gastric, the glossopharyngeal, the posterior motor, the trifacial, the common motor, and the olfactory, come from its lower face. The others arise more or less from its upper face. c. The origins of some, as the trifacial and the common motor, are deeply concealed in the substance of the parts of the cerebrum from the surface of which they emerge-. On the contrary, most of the others cannot be traced beyond the surface. 4th. Direction and progress. All go forward ; but they differ from each other in this respect, that the direction of the posterior ten is forward and outward, while the optic nerve proceeds forward and inward at its posterior part, unites with that of the opposite side, and does not go outward till after this union. The course of the olfactory nerve is obliquely inward and forward. I. HYPOGLOSSAL NERVE. § 1853. The hypoglossal nerve, hyoglossien, Ch. the ninth cerebral pair, the tivelfth of the usual method ( JV. lingualis médius , Haller ; gustalorius , Winslow ; lingualis, Vicq-d’Azyr ; hypoglossus , Winslow),^) arises from the anterior face of the medulla oblongata, passes through the anterior condyloid foramen, and is distributed principally to the muscles of the tongue. It commences by several fasciculi placed after each other from above downward. These fasciculi, arranged in a single series about half an inch long, describe a curved line, which is convex outward, as the superior and inferior are placed a little farther outward than the central. They come from the groove between the pyramid and the olivary body. The inferior arise below this latter eminence ; the superior begin a little above the centre of the groove. All are situated a little farther outward than the anterior roots of the first cervical nerve, the lowest of which are about two lines distant from above downward. The whole series of these fasciculi corresponds with much exactness to the origin of the glosso-phaijmgeal, and the pneumogastric nerves, and to that portion of the accessory nerve which arises from the medulla oblongata. They are always very distinctly separated from each other at their origin, and commence by several radicles, which are themselves generally composed of other smaller radicles. They vary in their number and situation. We admit from four to eight of them. They usually succeed each other uninterruptedly, so that the smallest radicles of the different fasciculi touch each other. Sometimes, however, we observe some which are more remote from the others, and even about a line distant from them, so that this arrangement divides them into two or three bundles of different sizes. These fasciculi reunite in cords which are generally two and sometimes three in number, each of which passing through a special opening in the dura-mater, proceeds from behind forward, from below upward, and from within outward, towards the posterior orifice of the anterior condyloid foramen. They rarely unite in a single trunk before they enter the dura-mater. Sometimes even an osseous septum divides them for the whole extent of the condyloid canal, into at least two halves, which unite only at the external orifice of this canal. On leaving the cranium the trunk goes downward, proceeding on the upper part of the condyle, and covered outward in the extent of about an inch, by that of the pneumo-gastric nerve, with which it is generally united by filaments, it passes on the internal carotid artery, and descends from behind forward between the laryngœal branch of the pneumo-gastric and the accessory nerve. In this place it unites at first near the summit of the transverse process of the first cervical vertebra forward and upward by a considerable filament, with the pneumo-gastric nerve downward and backward, with the first cervical nerve and the great sympathetic nerve by another filament which ascends from the anterior branch of the first, and from the superior cervical ganglion, before which it is situated. It then descends, covered outward by the pneumo-gastric nerve, the posterior belly of the digastricus muscle, the stylo-glossus muscle, and the internal jugular vein, inward by the internal carotid artery, and gives ramifications to the submaxillary gland. When as high as the third cervical vertebra, it passes before the external carotid artery, and forming a large arch, which is convex downward, it goes from behind forward and from below upward, towards the genio-glossus muscle, along the inside of the posterior and inferior hyoid bone. At the origin of its arch it gives off a considerable and very constant branch, the descending serviced nerve (R. descendons noni ), which goes downward and forward, first along the anterior face of the external carotid artery, where it is intimately united to the trunk of the pneumo-gastric nerve by cellular tissue, then to the inner side of the internal jugular vein, passes above the superior thyroid artery, goes still farther forward on leaving this point, gives off forward and inward a branch which terminates in the anterior belly of the omohyoideus muscle, sends others to the muscles of the larynx, and again uniting in the middle of the neck with the descending nerve which comes from the anterior branches of the second and third cervical turned forward. The convexity of this arch usually gives rise to two branches, which descend along the anterior side of the internal jugular vein. The superior is smaller, and retrogrades to go to the anterior belly of the omo-hyoideus muscle. The inferior is larger, passes under the anterior belly of this muscle, goes downward and forward to the external face of the sterno-thyroideus muscle, distributes several filaments in this muscle and the sterno-hyoideus muscle, and anastomoses in this place by a small but constant filament, with the diaphragmatic nerve. Some ramifications of this branch enter the chest, particularly on the left side, and extend to the upper part of the pericardium. The trunk of the hypoglossal nerve immediately gives off some branches which go downward into the thyro-hyoideus muscle. Thence it rises again, first below the tendon of the digastricus muscle, then on the external face of the hyoglossus muscle, gives filaments, of which the upper anastomose frequently from its upper and lower parts, but principally from this latter to the muscles of the larynx, then to the hyoglossus, to the genio-hyoideus, and to the genio-glossus muscle, unites with the lingual nerve of the third branch of the trifacial in the upper and anterior part of the hyoglossus muscle, by two or three considerable filaments, and afterwards extends almost to the point of the tongue by ramifications which proceed between the fibres of the hyoglossus muscle. At the body of the hyoid bone the trunk of the nerve turns on the lingual artery,, and enters the genio-glossus muscle, in which it terminates by branches, some of which go to the lower face of the point of the tongue. We cannot follow the filaments of the hypoglossal nerve into the integuments of the tongue ; they stop in the muscles of this organ. From this circumstance we might deduce the very probable conclusion that it serves only to excite the motions of the muscles, and that it is not the proper gustatory nerve, although it communicates by very large anastomoses with the lingual branch of the trifacial nerve, the ramifications of which penetrate distinctly into the integuments of the tongue. Another circumstance gives more weight to this conjecture, viz. the analogy between it and the motory nerves of the other organs of the senses which receive both nerves of sensation and of motion. That these two orders of nerves fulfill different functions, is demonstrated by the observation, that alterations, the primitive or accidental destruction of one of them, is attended only with the loss of one of the two faculties of the tongue, that of the taste when the affection is situated in the lingual branch of the trifacial nerve, and that of motility when the hypoglossal nerve is affected.(l) The loss of taste in one (1) The sense of taste is lost in trisma, but the levator muscles of the lower jaw receive their nerves from the fifth pair and not from the hypoglossal nerve (HaÜer, El.phys ., vol. v. p. 112). The congenital absence of taste has been observed in a patient where the lingual branch went to the occiput and not to the tongue (Colombo, De re anat., Paris, 1762, p. 486.) case where the hypoglossal nerve was injured(l) even when this lesion would not have been admitted as probable, would not prove that the two nerves concurred in the function of taste, for on one side the lesion might produce this effect only from the connections between the two nerves ; and secondly a case cited by Heuermann would farther prove that it cannot be admitted, since on account of the distribution of the hypoglossal nerve and of the lingual branch of the trifacial nerve, the hypoglossal nerve could not alone be the nerve of taste, as should be concluded from this fact, considered as a peremptory argument in favor of the power attributed by the author to the nervous trunk supposed to be injured. But the difference of function between the two nerves is not proved by the cases where the loss of the motion of the tongue without that of taste, or the loss of taste without that of the motion of the tongue(2) in general, have been observed, since the same phenomenon is seen in other parts which receive only one nerve, and which cannot consequently be explained in the same manner. II. ACCESSORY NERVE. § 1854. The accessory nerve, (3) trachelo dorsal , Ch. (JY. spinalis ad par vagum accessorius , accessorius Willisii),(4) arises by numerous filaments from the posterior part of the lateral face of the posterior cord of the spinal marrow, ascends between the posterior roots of the upper six cervical nerves and the ligamentum denticulatum, nearer the former than the latter, consequently also nearer the posterior than the anterior roots of the cervical nerves, penetrates into the skull through the occipital foramen behind the vertebral artery, receives some filaments from the latter parts of the medulla oblongata, is situated below near the pneumo -gastric nerve, with which it emerges from the skull through the posterior foramen lacerum, and is distributed partly in the upper region of the pharynx, partly also in some muscles of the back. Its lowest and smallest root usually arises at the height of the superior filament of the posterior roots of the seventh cervical pair ; the second at that of the upper part of the posterior root of the fifth ; the third and fourth at that of the upper part of the fourth ; the fifth opposite that of the third ; the sixth between the second and third ; and the seventh opposite the posterior root of the second. Many of these roots been figured by Eustachius and described by Coiter. (4) J. P. Lobstein, De nervo spinali ad par vagum accessorio, Strasburg, 1760. — A. Scarpa, Uber den zum achten Paare der Gehirnnerven hinlaufenden Beinerven des Rückenmarncs ; in the Abhandl. der Josephsakad, vol. i. p. 385. — Its origin has been described perfectly by Huber, De medulla spinali , specialim de nervis ab eâ provenientibus, Gottingen, 1741, § vii-xi. Sometimes, however, the whole posterior root of the first cervical nerve joins it and forms with it a small ganglion. But this ganglion is not constant when the nerves unite, and we should even think it extremely rare, since it has never been observed by Haller, Ash, Lobstein, and Scarpa, who have remarked only a slight thickening of the nerve. (1) We have never seen it but a few times, notwithstanding our numerous researches. Three or four roots generally arise within the skull from the lateral face of the posterior cord of the medulla oblongata ; these are behind the roots of the hypoglossal nerve. These ten or eleven roots gradually become longer and thicker from below upward, and go towards the trunk of the nerve at angles which are more acute the lower their origins. The lowest is in great part concealed in the pia-mater, through which it only penetrates. The spinal roots also are usually single, while those arising from the medulla oblongata are generally composed of two short radicles united at an acute angle, each of which is formed by three or four filaments. These radicles, one of which is superior, the other inferior, and the second of which ascends in a more perpendicular direction, soon reunite. In considering the whole series of roots, we recognize that they gradually become more anterior from below upward. The accessory nerve never arises lower than the point indicated. On the contrary it often commences higher, opposite the sixth cervical vertebra, sometimes even but more rarely opposite the fifth. In some subjects it receives from the spinal marrow only two or three roots, which are then proportionally thicker. The number of the filaments from the medulla oblongata is sometimes less than we have mentioned : it is rarely and perhaps never greater. Sometimes they resemble by being single those which arise from the spinal marrow. It generally passes through the dura-mater in connection with the pneumo-gastric nerve : but sometimes also it emerges through a special opening behind the latter, with which however it reunites. frequently in the same person on different sides of the body. In passing through the dura-mater the accessory nerve is inclosed in a sheath with the pneumo-gastric nerve ; but before emerging through the posterior foramen lacer um it divides into an internal and an external branch. The internal branch gives off first two branches which unite with each other and with a third which descends from the pneumo-gastric nerve, and produces the superior pharyngœal nerve. It then receives some filaments from the pneumo-gastric nerve, sometimes communicates with the hypoglossal nerve, then reunites with the trunk of the pneumo-gastric nerve to form a ganglion. The external branch proceeds for about two inches descending deeply behind the internal jugular vein, at first between this vessel and the occipital artery, then between it and the sterno-cleido-mastoideus muscle. It turns a little on this muscle and goes forward, sometimes passes through it, gives to it filaments which anastomose with those of the third cervical nerve, then continues to descend but from before backward, passing on the internal jugular vein, enlarges considerably by uniting with two anastomosing branches, the upper of which arises from the anterior branch of the second' cervical nerve and the lower from that of the third, passes on the levator anguli scapulae muscle, anastomoses with the ramifications of the fourth and fifth cervical nerves, and comes to the internal face of the trapezius, in which it is distributed. No other muscles receive filaments from it. § 1855. The pneumo-gastric , the par vagum , the middle sympathetic, the pulmonary , the vocal nerve, the eighth, or according to the new calculation, the tenth pair (JV. pneumo gastricus, Chaussier ; JV. vagus, JY. sympathicus médius, Winslow; JV. pulmonalis , Bartels ;(1) par octavum, Willis ;(2) decimum, Andersch),(3) arises from the side of the posterior prolongation of the cerebellum between the accessory and the glosso-pharyngœal nerves, emerges from the skull through the posterior foramen lacerum, and descending is distributed (3) Neubauer, Descript, nerv. cardiac. — Andcrsch, in the Nov. comm. Gott. vol. ii. published in Haase, Cerebri nervorumque anal., Leipsic, 1781, and in Ludwig, Script, neural, min. vol. ii. — Walter, De nerv, abdom., Berlin, 1800.— Wrisberg, Da gonglio plexuque semilunari, &c. sect, ii., De pari octavo ; in the same Comment. vol. i. 1800. — Scarpa, Tab. neurolog., Pavia, 1794. § 1856, It arises by from ten to sixteen filaments from the lower part of the lateral face of the posterior prolongations of the cerebellum. The inférior are situated far behind the anterior, and form a series which is generally single and five or six lines long. Sometimes, however, several are more anterior than the others ;(1) this is particularly the case with those at the top of the series, although there is no disposition indicating any tendency to produce distinct roots. On the contrary, in this formation the pneumo-gastric nerve is similar to the formation of the anterior cerebral nerves, as its origin is thus more rounded, which form is remarkable in several of the mammalia, particularly the ruminantia. These filaments arise principally towards the anterior and inferior edge of the posterior prolongation of the cerebellum, in the groove between this prolongation and the olivary body. They do not extend so high as this latter, and terminate below long before those of the hypoglossal nerve. Some of them frequently anastomose with the transverse medullary striae on the floor of the calamus scriptorius, and hence these striae seem to concur in their formation. (3) Others, particularly some of the inferior, come from the lower extremity of the olivary body. (4) These filaments are generally single, and not cleft at their internal part. They are sometimes separated and sometimes united from their origin in three or four fasciculi. The inferior are commonly very intimately connected with the accessory nerve. The superior most generally communicate by a transverse filament with the glosso-pharyngceal nerve even within the skull. These filaments and fasciculi unite in a flattened trunk about one line and a half broad, one quarter or one fifth of a line thick, and always larger at its upper part where they are interlaced with each other. This trunk goes outward and backward. It is inclosed in a small canal of the dura-mater, through which it comes from the cranium, through the anterior part of the foramen lacerum, before the origin of the internal jugular vein. It is separated from this vein by a prominence of bone which comes from the petrous portion of the temporal bone or from the occipital bone, or from both, and from the accessory and the glosso-pharyngceal nerves by the dura-mater. The fasciculi hitherto distinct do not entirely unite in a rounded cord except within this canal. The rounded cord on leaving the foramen lacerum is united very intimately by mucous tissue with the glosso-pharyngœal nerve, the hypoglossal and the ascending branch of the superior cervical ganglion. It is situated at first behind the glossopharyngœal and before the hypoglossal nerve, but it soon passes behind this latter, is separated from the glosso-pharyngceal nerve by the internal jugular vein, leaves the hypoglossal nerve on the transverse process of the first cervical vertebra, and descends outward and a little backward before the primitive carotid artery, between it and the internal jugular vein, intimately united to these two vessels by a mucous tissue destitute of fat and more loosely connected to the intermediate filaments of the sympathetic nerve which are situated behind it and placed in the rectus capitis major anticus and the longus colli muscles.(l) In passing through the foramen lacerum the pneumo-gastric nerve anastomoses by some filaments with the accessory nerve, and shortly after leaving this opening it communicates also with the glosso-pharyngoeal nerve and the superior cervical ganglion. It then gives off a branch which unites with two filaments from the inner branch of the accessory nerve, and gives rise to the pharyngœal or superior pharyngœal nerve (JY. pliaryngœus, s. pliaryngœus superior , s. primus.) This nerve goes obliquely from above downward and from without inward on the inside of the internal carotid artery, sends an anastomosing filament to the glosso-pharyngœal nerve, bulges a little, and forms at the height of the middle constrictor of the pharynx a considerable plexus termed the pharyngœal ( plexus pliaryngœus). This plexus receives filaments from the laryngceal, the glosso-pharyngœal nerves, and from the superior cervical ganglion ; its filaments are distributed principally in the middle constrictor, but some go to the upper constrictor of the pharynx : a few descend along the primitive carotid artery, where they anastomose with the ramifications of the glossopharyngœal and the superficial cardiac nerves. The inferior pharyngœal nerve (JY. pliaryngœus inferior , s. minor), which also is not constant, arises directly below the superior pharyngœal nerve. This nerve soon anastomoses with the preceding, and also with one or several of the anterior filaments of the superior cervical ganglion, sends filaments to the pharyngœal plexus, and is distributed in the middle constrictor of the pharynx. At the place where the pharyngœal nerves are given off and sometimes also a little higher, the trunk of the pneumo-gastric nerve becomes much thicker and its texture is closer for about an inch : its fasciculi separate very much, and a reddish gelatinous substance is deposited between them. A real ganglionnary plexus then forms. The remnant of the internal branch of the accessory nerve after sending an anastomotic twig to the pharyngœal nerve enters this plexus at about its centre, sometimes in one branch, sometimes also in several filaments which ramify and interlace differently, so that this branch forms the The trunk of the pneûmo-gastric nerve is in fact directly attached to this ganglion from before backward ; but it is sometimes, although rarely, connected with it only by some filaments of communication. A more distinct development of this plexiform dilatation of the nerve occurs when it divides into two portions which unite only at the lower part of the neck ; but such an arrangement is extremely rare : it has been observed only once in five hundred cases, and this was on the right side.(l) of this ganglion. This nerve descends between the internal carotid artery and the superior cervical ganglion, most generally anastomoses by one or several filaments with this latter, the pharyngeeal plexus, and the hypoglossal nerve, and divides into an external and an internal branch. The external goes inward, and sends filaments to the inferior constrictor muscle of the pharynx, the crico-thyroideus, the sterno-thyroideus, and the hyo-thyroideus muscles, to the thyroid gland, and to the membrane of the pharynx ; these filaments enter the cavity of the larynx between the cricoid and thyroid cartilages. The internal branch passes through the hyo-thyroid membrane between the hyoid bone and the thyroid cartilage. It distributes soft and thick filaments in the membrane and glands of the epiglottis, the mucous membranes of the pharynx and larynx, several small muscles of the larynx, particularly the arytenoideus and the crico-thyroideus, and anastomoses with the filaments of the inferior and recurrent laryngœal nerve. After the superior laryngœal nerve, we see arise either from the ganglionnary plexus or directly below it some filaments which are not constant ; these unite to the descending branch of the hypoglossal nerve, and also to the first cervical nerve, and to the soft nerves which go to the internal carotid artery. After giving off these branches, the trunk of the pneumo-gastric nerve becomes more compact, and descends in the manner mentioned above, but gives off no ramifications. It then represents a cord composed of less distinct fasciculi and which is generally uneven by a kind of indentation, but its surface is surrounded here and there by very minute filaments which interlace like a plexus. (2) It gives off about an inch or an inch and a half above the origin of the primitive carotid artery (but an inch higher on the right than on the left side), and at about the centre of the neck, on both sides, the cardiac nerves (R. cardiaci). These descend from within outward and from behind for- ward in the carotid artery and the innominata trunk, anastomose with the superficial cardiac nerves, and are distributed to the arch of the aorta. We generally find three or four on the right side, the upper of which is the largest and most constant. There are one or two on the left side. The trunk of the pneumo-gastric nerve goes forward, is situated behind the innominata vein, passing on the right before the subclavian artery, on the left before the arch of the aorta, thus comes into the chest, enlarges considerably, and divides into two halves, of which the lower and larger is the continuation of the trunk, and the upper is smaller, and is termed the inferior laryngœal ascending or recurrent nerve, tracheal, Ch. (JV. recurrens , s. adscendens, s. laryngeus inferior). The two recurrent nerves arise within the chest, the left much lower than that of the right side. They ascend first from before backward, then vertically, send some filaments to the cardiac nerves which come from the pneumo-gastric, the middle and inferior cardiac nerves which come from the ganglionnary nerves, form with them a plexus, then turn from before backward, the right on the right subclavian artery, the left on the extremity of the arch of the aorta, and are placed behind the primitive carotid and inferior thyroid artery, between the trachea and the esophagus, and rise to the larynx. In this course they give off first the branches called the superior tracheal nerves (R. tracheales superiores), which descend before the trachea and anastomose with the preceding, arrive at the bronchia and the pulmonary plexus of their side, are distributed in the membrane of the trachea, the pharynx, and the thyroid gland, and communicate with some filaments of the cervical portion of the sympathetic nerve. Finally, when as high as the larynx the recurrent nerve is distributed in the inferior constrictor of the pharynx and the cricoarytenoid muscles, enters the cavity of the larynx between the cricoid and thyroid cartilages, and terminates in the thyroid cartilage, the arytenoid muscle, and the mucous membrane of the larynx, by anastomosing by several branches with the superior laryngœal nerve. The recurrent nerve is sometimes double, but this is rare, and when it occurs it is always on the right side, if we judge from observations made hitherto. The unusual nerve is smaller than the other, and arises from the trunk some lines below it, turns like it on the subclavian artery, ascends between the esophagus and the trachea, anastomoses by a large twig with the normal recurrent nerve, and is distributed with the latter.(l) This anomaly seems to indicate an effort to establish a perfect similarity between the right and left sides, since the recurrent nerve always arises lower than that of the right side. is connected with the primitive shortness of the neck, since the larynx is much nearer its origin in the early periods of life than subsequently. This hypothesis would explain its arrangement in the same manner as the high origin and long course of the spermatic vessels. Farther, it is impossible to deny the analogy between the distribution of the nerves and vessels in this region of the body, since the superior and inferior laryngoeal nerves and the superior and inferior thyroid arteries manifestly correspond. the recurrent nerve, goes backward on the posterior face of the trachea. There it supplies first five or six inferior tracheal nerves ( V. trachéales inferiores ), some of which proceed before, others behind the trachea. The former anastomose with the filaments of the superior tracheal nerves and with others coming from the inferior cervical ganglion. Some descend before on the ramifications of the bronchiæ and of the pulmonary artery. Others enter the muscular and mucous tunics of the trachea, bronchia, and esophagus, and terminate in the pulmonary plexus {plexus pulmonalis ) . This plexus commences directly above the bronchia of each side. It is formed principally by the fasciculi of the trunk of the pneumogastric nerve, between which there is a very vascular mucous tissue. It extends behind the bronchiæ into the substance of the lungs, surrounding the finest ramifications of the bronchial tree, to the muscular tunic, and even to the mucous membrane to which it sends filaments. Beside the trunk of the pneumo-gastric nerve which develops itself to give rise to it, it also receives some filaments which are less numerous, from the superior thoracic and from the inferior cervical ganglion of the great sympathetic nerve. Five or six fasciculi on the right side and only two or three on the left, arise from the lower part of each of these two pulmonary plexuses. These fasciculi are first situated very far from each other, but frequently anastomose by intermediate filaments. After passing some lines they unite on each side in a cord, which is the continuation of the trunk of the pneumo-gastric nerve, and the right of which is larger than the left. These cords descend, that of the left before, that of the right behind, and at the side of the esophagus. In their course they frequently anastomose principally by anterior filaments which descend from the right cord, send filaments to the esophagus, and others which are smaller to the aorta, and enter the abdomen with the esophagus, passing through the esopahgœan fissure of the diaphragm. The pneumo-gastric nerve terminates in the stomach. That of the right side which is the largest, goes to the right portion and the posterior face of the viscus ; that of the left side is distributed in its left part and on its anterior face. The right forms around the cardiac orifice a large plexus, from which numerous filaments arise, some of which are distributed to the posterior face of the stomach ; others situated behind the coronary artery of the stomach, proceed along its small curve to the pylorus, and there anastomose with those of the left nerve and with the superior gastric plexus of the great sympathetic nerve : finally, some which do not belong to the stomach pass behind it, arrive at the right portion of the solar plexus and also the plexuses which come from this latter on the right side, and are distributed to the hepatic artery and its branches, to the vena-portæ, the duodenum, and the pancreas. The left divides at the cardiac orifice into several branches which separate in rays, communicate less frequently, follow the small curve of the stomach from left to right, send ramifications to the anterior face of this viscus, anastomose near the pylorus with the filaments of the right pneumo-gastric nerve, and leaving the stomach, terminate anteriorly before the pylorus, in the hepatic plexus formed by the ganglionnary nerve. § 1858. The glosso-pharyngceal nerve (N. glosso-pharyngœus, Haller; s. lingtiulis pnewnogastrici, Vicq-d’Azyr; s. octavus, Andersch), has been considered until lately as the anterior part of the pneumogastric nerve. In fact, if we regard its origin, the communications between it and this nerve, both, within the skull and at its passage through the posterior foramen laeerum, finally the manner in which it is distributed, we discover that it really forms a part of the pneumogastric nerve, but it is so largely developed that it may be considered a proper and distinct nerve. It arises by five or six filaments, which may be easily separated from each other, and the anterior of which are generally smaller than the posterior. It arises between the pneumogastric and facial nerves, some distance behind the latter, but directly before the upper filaments of the first, from which its own cannot be separated. It comes from the upper part of the lower face of the inferior prolongation of the cerebellum, from the depression between this cord, the olivary bodies, and the posterior edge of the annular protuberance, directly behind the latter, from which several of its filaments sometimes emanate. It goes outward and at first a little forward, covered by the fourth lobe of the cerebellum, usually anastomoses within the skull by a large branch with the pneumo-gastric nerve,(l) and after proceeding five or six lines, passes through the arachnoid membrane. It is round and about a half or three quarters of a line thick, and emerges from the skull through the anterior part of the posterior foramen laeerum, directly before the pneumo-gastric nerve, but inclosed in a special canal of the dura-mater. About four or six lines from its entrance into this canal, it becomes a small, oblong, rounded, and generally very distinct ganglion about five lines long, which extends into the canal of the dura-mater and the anterior part of the foramen laeerum. This ganglion gives off, above, a filament, which enters into the cavity of the tympanum, and then divides into two branches ; one ascends along the promontory, gives off a small filament to the membrane of the foramen rotundum, and passes through the petrous portion of the temporal bone to the superficial temporal nerve, and the other passes below the osseous portion of the Eustachian tube, and goes to the carotid canal, where it anastomoses with the great sympathetic nerve.(l) The ganglion also gives off other filaments, which passthrough the canal of the dura-mater to go to the trunk of the pneumo-gastric, to the accessory, and the great sympathetic nerves. After emerging from the posterior foramen lacerum, 'the glossopharyngeal nerve is separated from the pneumo-gastric trunk by the internal jugular vein, before which it is situated. Thence it goes downward and forward, passing on the internal carotid artery, descends situated at first closely on the outside, then on the anterior part of this artery, between it, the external carotid artery, and the stylo- pharyngceus muscle, passes between this muscle and the glosso-pharyngceus muscle, then between this latter and the hyoglossus, and thus comes to the lower and posterior part of the tongue. On leaving the skull it sends a filament of anastomosis to the stylohyoid branch or to the digastric branch of the facial nerve and another to the trunk of the pneumo-gastric nerve. It then gives off one or two which descend along the internal and the primitive carotid arteries, anastomose first with the pharyngœal branch of the pneumo-gastric nerve, and then going to the lower part of the neck communicate with some filaments of the sympathetic nerve particularly with the superficial or even the middle cardiac nerves. Still farther on, it sends off three or four filaments to the stylo-pharyngeus muscle, and also to the middle and superior constrictors of the pharynx and to the amygdalæ, and some which enter the pharyngœal plexus of the pneumo-gastric and the ganglionnary nerve. The glosso-pharyngceal nerve then passes between the styloglossus and hyoglossus muscles ; then situated in the tongue below the lingual nerve of the fifth pair and above the hypoglossal nerve, both larger than it and with which it does not communicate at least by very evident filaments, it is distributed partly in the muscles of the tongue, the membrane of the soft palate and the amygdalæ by several ramifications which interlace like a plexus ; partly in the integuments of the base of the tongue, its large papillæ, and the mucous membrane of the epiglottis by other filaments which are situated lower and nearer the median line than the preceding, and pass from below upward through the substance of the tongue. (1) Rosenmuller, Handbuch der Anatomic, 1816. p. 407. — Jacobson, in the Acta reg. societ. Hqfniensis medicæ, vol. v. Copenhagen, 1818. p. 292.— This anastomosis has been doubted by Kilian, but is admitted by Lobstein. § 1859. The auditory or acoustic nerve, labyrinthique , Ch., the soft portion of the seventh pair ( JY . auditorius , s. acusticus , s. portio mollis nervi acustici),(l ) is very soft, but harder than the olfactory and the portion of the optic nerve behind the decussation ; it generally communicates so evidently with all the white striæ of the floor of the calamus scrip torms, or at least with several of them, that it may be said to arise partially from it. Its upper and external part is formed by these striæ. The fibres connected with it follow one another from before backward and are separated by unequal and inconstant spaces ; they turn on the inferior prolongations of the cerebellum, on the surface of which they are intimately connected. Their direction is forward and downward, the anterior proceeding transversely, the posterior obliquely from below upward. The inner part of the nerve is larger than the external portion, but they are not separated ; it arises below and farther forward than it from the lateral face of the spinal prolongation of the cerebellum, directly before and above the glosso-pliaryngœal nerve and the upper part of the pneumo-gastric nerve. The trunk of the nerve then goes forward, outward and downward on the posterior edge of the transverse prolongation of the cerebellum, and is united to its upper face so intimately for about three lines, that it may properly be considered as arising from this part of the encephalon. It is slightly covered outward by the fourth lobe of the cerebellum, being often attached in this place to its medullary substance, so that we may admit also that it partially arises there, which is worthy of note but not astonishing, on account of the analogy resulting from it with what is seen in the other two nerves, the optic and olfactory, which are only nerves of sense. Its internal face is grooved lengthwise, and receives the facial nerve. It is soft at its origin, and we do not perceive there distinct fibres, but on leaving the encephalon it evidently becomes fibrous and still more solid. On leaving its origin the auditory nerve goes obliquely forward, outward, and upward, and soon penetrates the internal auditory foramen, which is much larger than it. It then divides into two branches, which continue united externally to its base ; the anterior enters the cochlea and the posterior , the vestibule and the semicircular canals. We shall describe these branches when speaking of the ear. (1) J. F. Meckel, Obs. anat. sur la glande pineale, sur la cloison transparente et sur Vorigine de la septième paire , in the Mêm. de Berlin , 1765. p. 91—100.— A. Scarpa, De nervo auditorio , in his Anat. disquis. de auditu et otfadu, Pavia, 1789, sect. ii. cap. iii. § I860. The facial or small sympathetic nerve, the hard portion of the seventh nerve, the seventh pair, th eseventh cerebral nerve (JV. facialis, s. sympathicus minor , s. communis facili, s. portio dura septimi, s. nervus primus septimi paris, s. par septimum){ 1) is much smaller than the auditory nerve ; it arises by two roots which are generally distinct, although placed one against the other. One is external and posterior, the other much larger is internal and anterior. It arises within, below, and before the auditory nerve, which receives it in a groove situated along its internal face, directly at the side of this nerve and before the glosso-pharyngæal nerve. It arises from the posterior edge of the annular protuberance, from the uppermost part of the lower face of the rachidian prolongation of the cerebellum ; sometimes, also, according to Malacarne, by several filaments from the floor of the fourth Ventricle, that is, from the most anterior transverse medullary striae. The filaments from the annular protuberance, particularly the internal, seem to come only from this tubercle ; but examining them attentively, we see that they are separated from the principal root only by the posterior fibres of the protuberance existing between this latter and them.(2) Very possibly, however, from this reason they are in fact separated from the principal root, and first arise from the pons Varolii. The external root of the nerve, which is much smaller than the internal, is always formed of three or four filaments which unite anteriorly in one or two fasciculi. It is situated between the internal root and the auditory nerve, and some of its filaments frequently seem, at least in situation, to belong to the auditory nerve rather than to it. The nerve leaves the annular protuberance at about the centre of the space between the anterior and posterior edges of this latter, goes forward and outward to arrive at the internal auditory passage, through which it proceeds above and before the auditory nerve to the canal of Fallopius, which it exactly fills, and passes entirely through it. Its direction is consequently first outward and backward, then downward behind and above the cavity of the tympanum, and it emerges through the stylo-mastoid foramen, to be distributed in a considerable portion of the skin and of the muscles of the head. In its course along the canal of Fallopius, it gives off first downward and forward, a filament which reunites with the superior branch of the recurrent nerve given off by the second branch of the fifth pair, to form the superficial petrous nerve ( JV. petrosus superficialis). (1) J. H. Meckel, De quinto pare nervorum cerebri, Gottingen, 1748, for the portion of the facial nerve contained in the Fallopian canal. — J. F. Meckel, Dissertation, anatomique sur les nerfs de la face, in the Mém. de Berlin, vol. vii. 1752.— See also Bock, Beschreibung des fünf ten Nervenpaares, Leipsic, 1817. tab. i. ii. bones of the ear. A little lower, some distance above the stylo-mastoid foramen, it sends off a considerable branch, the cord of the tympanum ( chorda tympan; ), which descends at first along the trunk, then goes outward and upward, passes through the posterior wall of the cavity of the tympanum, enters this cavity at the side of the pyramid, descends from behind forward between the malleus and incus situated on the former bone : it anastomoses by one or more filaments with the tympanitic nerves of the fifth pair, but gives no ramification to the membrane of the tympanum, leaves the tympanum through the fissure of Glaser, descends on the inside of the ascending branch of the jaw, and gradually becoming thicker, anastomoses at an acute angle with a twig of the lingual branch of the trifacial nerve which meets it. It does not seem to us probable, from our dissections, that the superficial petrous nerve and the cord of the tympanum, are only a filament of the fifth pair, which is fitted to the facial nerve, and which does not really anastomose with it,( 1 ) although we consider the lower and prominent portion of the cord of the tympanum, as belonging to the branch of the trifacial nerve. the following branches: 1st. One single or double branch, termed the posterior, inferior , or deep auricular nerve (JV. auricularis posterior , profundus inferior) , which sends one or more inconstant filaments into the mastoid process, then goes upward and backward and divides into two branches, an anterior and a posterior, the former of which is the larger. The posterior, which sometimes forms the first branch of the facial nerve, ascends on the mastoid process, is distributed in the skin which covers it, extends to the occipitalis muscle, to which it distributes filaments, and anastomoses with the ramifications of the small occipital nerve. The anterior arrives at the lower and posterior part of the cartilaginous portion of the auditory foramen, and of the external ear, sends some filaments to the skin of this region, and also to the posterior auricular muscle, and passing through the cartilage, is distributed in the integuments of the auditory passage. 2d. The stylo-hyoid nerve (JY. stylo- hyoidcus) which is distributed partly in the upper portion of the muscles attached to the styloid process, and the posterior part of the digastricus muscle of the jaw, and partly sends several anastomosing filaments to the upper part of the ganglionnary nerve, and to the middle cutaneous nerve, given off by the third cervical nerve. 4th, Sometimes a filament which anastomoses with the posterior twig of the inferior auricular nerve, and with the filaments of the anterior branch of the third and fourth cervical nerves. This filament exists particularly when the inferior auricular nerve is small. After giving off these ramifications, the trunk of the facial nerve, passing under the ear, enters the parotid gland from above downward and from behind forward, assumes in this gland a direction which is oblique from below upward, still continuing to go forward, and forms within it a considerable plexus, the parotid 'plexus (plexus par otideus). This plexus i formed by the nerve dividing at the posterior edge of the ascending branch of the jaw, into from two to five branches, which may always be referred to two which vary in direction and distribution. Of these branches, one is superior, the other inferior, and smaller than the former. They anastomose frequently together, and thus form a polygon convex forward, upward and downward, whence arise the other ramifications of the nerve, which are distributed in the 6kin of the upper, middle, and lower portions of the face, in that of the upper part of the neck and in most of the muscles of the face. Several considerable branches constantly unite posteriorly with this plexus ; they come from the superficial temporal nerves which arise from the third branch of the trifacial nerve, and which turn from behind forward on the posterior edge of the ascending branch of the jaw. By examining this plexus from above downward and from behind forward, we observe that it gives off some ascending, some anterior, and some descending branches, which frequently anastomose together by intermediate twigs, equally distant from the edge of the parotid 5th, 6th, 7th. Two or three temporal nerves, which give some small filaments to the parotid gland, ascend on the malar bone, anastomose between them with the superficial and deep temporal branches of the submaxillary nerve posteriorly, and with the frontal and lacrymal twigs of the first branch of the trifacial nerve, are distributed on the temporalis muscle, and send ramifications to the skin of the temples, to that of the anterior part of the external ear, the anterior auricular muscle, § 1863. 8th and 9th. These are usually two nerves ; they proceed more forward and upward than the preceding, and passing on the malar bone, they are distributed in the skin which covers this bone and the external edge of the orbit, in the outer part of the eyelids, in the external and lower part of the orbicularis palpebrarum muscle, finally in the posterior part of the zygomatici muscles. The central one is the largest. They go almost directly forward on the upper and middle portion of the masseter muscle, beyond its anterior edge. The middle is situated directly on the excretory canal of the parotid gland. The superior, passing under the zygomatici muscles, to which it gives filaments, ascends towards the lower eyelid, and goes to the inner angle of the eye, where it often anastomoses with the infratrochlear nerve given off by the fifth pair. The central divides into ascending and anterior twigs. The ascending twigs arrive at the lower part of the orbicularis palpebrarum muscle, the muscles of the sides of the nose, and the skin which covers them, anastomose with some filaments of the infraorbitar nerve which come from the fifth pair, particularly with the external, and terminate in the levator muscles of the upper lip, the orbicularis oris, and the skin of the upper lip. The inferior go directly forward, are distributed in the buccinator muscle, the skin of this region and that of the lower lip. They anastomose wfith the buccal nerve which comes from the third branch of the fifth pair. III. DESCENDING BRANCHES. § 1865. The descending branches, cervico-faciales, Ch., arise from the lower and smaller trunk, which commonly anastomoses at its origin by some filaments with the superior. This trunk generally divides into two branches. The superior goes forward on the lower part of the masseter muscle, anastomoses with the inferior buccal nerve, and is distributed in the skin of the lower bp, the depressor labii inferioris, and the buccinator muscle. The superior twig, the marginal nerve (N. marginalia), proceeds above and along the edge of the lower jaw, goes forward and upward, distributes its filaments in the muscles which depress the lower lip and in the skin of the chin, and anastomoses with the inferior labial nerves of the third branch of the trifacial nerve. The inferior divides in turn into two or three ramuscules, the superior cutaneous cervical or submaxillary nerves (JV. subcutanei colli superiores ), which descend under the jaw, are distributed in the upper part of the skin of the neck and in the platysma myoides muscle, and anastomose frequently with the ascending twigs of the anterior branch of the third cervical nerve. § 1866. The external motor nerve, the sixth pair, the external oculomuscular nerve ( JY. '. oculo-muscularis externus, s. posterior, s. abducens, s. par sextum),{\) is flat, and arises by two very distinct roots, an internal and an external which is usually four times the size of the former, from the upper extremity of the pyramid, from the posterior edge and the posterior extremity of the lower face of the annular protuberance, about two lines from the median line, and four or five lines inside of the facial nerve. From the inferior face of the annular protuberance only the inner root generally arises, which sometimes does not extend to the posterior edge, but terminates two lines from this edge and arises only from the external face of this protuberance, although we cannot follow it farther either backward or forward. The external root generally arises also from the anterior extremity of the pyramid. These two roots, particularly the internal, are formed of several fasciculi which are easily detached from each other. filaments by which the nerve arises do not unite in two distinct roots. Sometimes the nerve arises only from the pyramid. Not unfrequently it comes in part from the olivary body and the transverse band which is often found between the summits of the two pyramids. (3) We can, however, generally demonstrate particularly by comparative anatomy, that it arises from the medulla oblongata between the olivary bodies and the pyramids, much lower than it comes from them and that the different filaments coming from the olivary bodies, the small transverse striæ, and the pons Yarolii, are either supplementary, or as is true particularly of those from the annular protuberance, ap- pear to be distinct roots only because the fibres of the principal root of the nerve are separated from each other at their upper part by the posterior fibres of the pons Varolii.(l) The two roots generally unite before passing through the dura-mater : sometimes, however, each passes through a special opening in this membrane and also proceeds three or four lines and even glides under a special fibrous bridge entirely distinct from the dura-rnater before they join. In the cases where we have seen this arrangement it has ahuaijs appeared on the left side alone , and the external fasciculus was the smaller. These facts, compared with those adduced by Sœmmerring, seem much in favor of the opinion that the ganglionnary nerve comes from the centre of the nervous system, and that the cerebral nerves appear to be more numerous than they truly are by the enlargement of some branches. If proved that the external motor nerve always divides on the left side, it would be important on account of the analogy which it establishes with the vascular system. On leaving the encephalon the nerve becomes fibrous, is covered with a neurilemma and goes directly forward and outward, passes through the dura-mater below the posterior clinoid process, enters the cavernous sinus within which it is attended a short distance by the arachnoid membrane, being separated from the blood by the inner membrane of the sinus, and is situated on the outside of the internal carotid artery to which it is attached by compact cellular tissue. In passing above the anterior orifice of the carotid canal it anastomoses with the ganglionnary nerve by some filaments which form an acute angle with its trunk. Farther forward it communicates also by a filament with the spheno-palatine ganglion, or the recurrent nerve of the second branch of the trifacial nerve. It goes to the orbit through the sphenoid fissure through a special opening in the dura-mater, enters this cavity between the fasciculi of the rectus oculi externus muscle, intimately united in this place with the common motor nerve and the nasal nerve of the first branch of the tiifacial nerve, and coming on the inside of the rectus externus muscle is entirely distributed to it. The external motor nerve goes then only to one muscle. It very rarely gives off the nasal branch of the fifth pair, (2) but more frequently sends a filament to the opthalmic ganglion. (3) This latter arrangement makes the transition from that commonly found to the first. This anastomotic filament, however, undoubtedly belongs at least in part to the ganglionnary system. § 1867. The trifacial nerve, the fifth pair , (N. trigeminus , s. divisas, s. mixtus , Gj.11, s. pur quintum nervorum), ( 1) is very large: it appears ab 3 at six lines before the posterior edge of the inferior prolongation of the cerebellum, three behind the anterior edge of this prolongation, and nine from the median line of the pons Varolii. There it is manifestly composed of three more or less distinct roots, a posterior, a central, and an anterior. The posterior is situated farther backward and higher than the central, and the anterior below and on the inside of it. These roots were first correctly described by Santorini, (2) and after him by Wrisbsrg,(3) Palletta,(4) and Niemeyer.(5) § 1833. Tne central root is always much larger than the other two, for it is more than a line and a half in diameter after it emerges, while each of the others is only about half a line. Its fasciculi are more numerous : but they are smaller than those of the other two roots. downward, but soon enlarges, becomes round, and again contracts. The fibres of the annular protuberance evidently separate at their base, so that we may judge from a superficial examination that the root does not arise in this place but from a deeper part. This middle root is composed of thirty or forty fasciculi of various sizes. The number of filaments which form these fasciculi is about one hundred : some authors assert less ; but they probably have described the fasciculi simply as filaments, or have neglected to decompose several of them. It is principally by following the central root that we can demonstrate very evidently that the nerve arises from a deeper part than where it leaves the annular protuberance. Santorini has stated perfectly its true origin ;(6) his observations have been confirmed and (1) J. P. Merkel, De quinto pare nervorum, Gottingen, 1748. — A. B. R. Hirsch, Paris quinti nervorum encephali disquisitio anaiomica , Vienna, 1765. — H. A. W'risberg, Observations anatomicce de quinto pare nervorum et de nervis , qui ex rodem duram matremingredifalso dicuntur, Gottingen, 1777. — A. C. Rock, Beischreibung der fünften Nervenpaares und seiner Verbindung mit andern Nerven, vorzüglich dem Gangliensystem, Meissen, 1617. — G. K. Treviranus, Sur les nerfs de la cinquième paire, considérés comme organes ou conducteurs de sensations ; in the Journ. compl. du diet, des sc. méd. vol. xv. p. 207. — Magendie, Sur les fonctions de la cinquième paire de nerfs ; in the Journ. de phy. exp., vol. iv. p. 176 and 302. (6) Loc. cit., p. 65. T. he honor of this discovery then belongs to Santorini. Niemeyer seems to attribute it to Winslow, and is consequently wrong, for the Anatomy of Winslow appeared first in 1732, while Santorini’s observations were published in 1724. Here also the posterior part and the proper origin of the nerve are covered by the considerable development of the cerebral parts. On leaving the place where it appears, it enters from without inward, from before backward, and from below upward in the fissure of the central prolongation of the cerebellum, and is more or less completely divided into several cords by the transverse fibres of the annular protuberance, thus comes behind the union of the three peduncles of the cerebellum directly below the floor of the fourth ventricle, passes under the posterior prolongation of the cerebellum, almost the length of the exteinal edge of the annular protuberance, and proceeds towards the groove between the restiform and the olivary bodies ; its strongest root arises there partly from the groove and partly from the olivary eminences. From this point to where it passes between the posterior and lateral prolongations of the cerebellum it is not fibrous, and is surrounded by gray substance ; but from this second point to its emerging from the annular protuberance it is formed of very apparent fibres, and is surrounded by a thin membrane. In its whole extent from its origin to a little before its emerging on the external face of the inferior prolongation of the cerebellum it gradually becomes thicker, but before leaving the pons Yarolii it slightly contracts and enlarges considerably after emerging. The fasciculi of the nerve are then more distinct and surrounded with neurilemma, and occupy the w’hole circumference of the pons Varolii. They enlarge partly by the separation and partly by the increase of their substance. When once emerged, the nerve is at first round but gradually becoming flatter, goes forward towards the upper end of the petrous portion of the temporal bone. At first it is loose in the skull, being loosely surrounded by a broad prolongation of the arachnoid membrane, but at the upper edge of the petrous portion of the temporal bone it enters a rounded and oblong sheath of the dura-mater which generally is entirely separated from the cavernous sinus. This sheath is at first loose, but afterwards is placed strongly on its surface. It thus goes from before downward and from behind forward on the anterior face of the petrous portion of the temporal bone. In this course the trifacial nerve examined externally seems formed only by fasciculi placed one at the side of another. These fasciculi, however, communicate their whole extent, by small intermediate filaments. This union and the ramification of fasciculi which resultsfiom it, become more and more marked from behind forward, and for about a line and a half to two lines the breadth of the fasciculi divide into very minute filaments, and interlace perpetually with each other near its anterior extremity. The trunk of the nerve which here touches outward the last curve of the internal carotid artery anastomoses with some filaments of the great sympathetic nerve. In fact at the anterior extremity of the upper face of the petrous portion of the temporal bone it forms a semicircular prominence, the concave edge of which is turned upward and backward and the convex edge downward and forward. This prominence which reaches beyond the trunk of the nerve in every direction is six to ten lines long from before backward, one broad from within outward, and a line and a half high. It is termed the semilunar ganglion or gangliform plexus {ganglion semilunare , plexus ganglioformis , Vieussens ; intumescentia ganglio ajfinis, Scarpa ; plexus retiformis, Santorini ; tarda nervosa , Haller ; intumescentia semi-lunaris , Wrisberg ; Jigger lunatus, Neubauer ; Armilla , Malacarne). It is transparent and reddish, and for about a quarter to half a line has no determinate texture, if we except some filaments which pass over its two faces, particularly the inner part of the inferior : but it then reassumes its fibrous appearance, so that in the mode directly the opposite of that over the plexus the filaments unite from above downward in larger threads, and thus produce fasciculi, still forming a trunk from one and a half to two lines broad, which immediately divides into three principal branches, the upper of which forms with the crural a very acute angle, and the latter a slightly obtuse angle with the posterior. The branches, the fasciculi of which still interlace with each other, are at first broad, but they gradually become round in approaching the openings through which they pass. The plexiform filaments of the nerve are not generally continuous with the inferior, but terminate in a channel grooved on the upper and concave edge of the ganglion. The inferior arise from all the circumference of the ganglion, and most generally extend to the upper and concave edge externally. The substance of the ganglion is homogeneous internally, and precisely similar to that of the proper nervous ganglions. § 1869. The small roots of the trifacial nerve do not contribute to form the prominence of the ganglion, although there is on the lower face of this latter, and of the large root, a groove formed by their passage. The superior penetrates through a special fissure into the inferior prolongation of the cerebellum from one fourth of a line to two lines distant from the great middle root. When the two roots are very near each other they seem to enter through the same fissure : but in attentively examining we perceive this is rarely the case, even if it ever happens. The direction of the superior root in the inferior prolongations of the cerebellum is the same as that of the preceding, which proceeds below it; we however cannot trace the former as far. Soon after emerging', it turns on the upper face and the inner edge of the large root, arrives at its lower face, and continuing to pass on, it goes gradually outward where it reunites, after passing about half an inch, with the small inferior roots. It is formed of from three to six fasciculi of different sizes. The small inferior root is generally nearer the central than the superior, being often only a fourth of a line and seldom more than one line distant from it, and the rule mentioned by Palletta that they are always several lines distant cannot be admitted. They often evidently arise from the same groove. The part of the small inferior root which is contained in the cerebral substance always proceeds below the large in the same direction with it, and less distant from it than is the upper root. It is generally formed of a greater number of fasciculi than the upper, as there are about from six to eight. It leaves the annular protuberance on the lower face of the large root, and reunites with the small superior root in the manner stated, most generally, three or four lines behind the ganglionnary prominence of the large root. The trunk of the temporo-buccal nerve (N. crotciphito-buccinalorius), formed by this union, passes first under the large root, then under the ganglionnary prominence and the third branch of the fifth pair, thus goes outward and forward, and anastomosing in this course only by some inconstant filaments, first with this trunk, then with the third branch of the fifth pair, often but not always enlarges longitudinally under the plexiform ganglion, and after passing through the foramen rotundum of the basilar bone proceeds to form the temporal and buccal nerves. is whiter and harder than the large. Their separation with the ganglion formed by the large portion is extremely curious, as it presents a repetition of the formation peculiar to the nerves of the spinal marrow. A. FIRST PRINCIPAL BRANCH. § 1870. The first branch , the superior or ophthalmic branch of the fif III pair (R. primus , s. superior , s. ophthalmicus), (1) is much smaller than the other two, and arises from the upper part of the ganglion. Its direction is from below upward and from behind forward on the outer side of the cavernous sinus towards the orbit, into which it penetrates from within outward, on the outside of the common motor and below the superior motor nerve. In this course it gives off no branches, except nearer or farther from its origin a tolerably constant twig which unites to the superior motor nerve, and another less constant which goes to the ganglionnary nerve. Just before entering the orbit it generally divides into two and more rarely into three twigs, which aie the nasal , the lachrymal, and the frontal nerves. In the first case, the second blanch, which is larger than the other, is the common trunk of the lachrymal and frontal nerves. 1st. The nasal or nnso-ciliary nerve (N. naso-ocularis , s. nasociliaris), which in respect to size is between the other two, anastomoses posteriorly with some filaments of the great sympathetic nerve, and divides into two branches generally before entering the orbit. The external branch (R. ciliaris, s. ad ganglion ) is the smaller, and goes to the lenticular or ciliary ganglion ( ganglion lenticulare, s. ciliare ), which is situated on the outside of the optic nerve and forms its long root. Sometimes it anastomoses previously by one or two filaments with the common motor nerve.(l) It rarely gives off a ciliary nerve. The internal branch is larger and proceeds forward and inward on the optic nerve, with which it is connected. It not unfrequently gives off some ciliary nerves which proceed along the optic nerve to the eye and enter its capsule at its posterior part, proceed between the fibrous envelop and the choroid membrane to the iris, in which they are distributed with analogous but more numerous filaments which come from the lenticular ganglion, forming with them from five to ten nerves which generally divide again into two, more rarely into three fasciculi, which we shall describe when speaking of the eye. Several filaments from the ganglionnary nerve enter the ganglion. (2) The nerve then passes below the rectus oculi superior and obliquus major muscles, continues Bto proceed inward and forward, situated against the internal wall of the orbit, and soon divides into two branchés, the ethmoidal and the infra-trochlear nerves. The ethmoidal or internal nasal nerve (N. cthmoidalis, s. nasalis, Winslow, s. ophthalmicus, Willis, s. nasalis internus ), re-enters the skull through the internal and anterior orbitar foramen, afterwards emerges from this cavity through one of the anterior foramina of the cribriform plate of the ethmoid bone, proceeds to the nasal fossa, sends filaments to the mucous membrane of the superior turbinated bone and of the septum, sends others to that of the frontal sinus, then glides in a groove of the nasal spine of the frontal and of the proper nasal bones, descends along the anterior edge of the cartilaginous septum of the nose to the nasal fossee, emerges, and terminates at the tip of the nose sending filaments to its alæ, at the end of which it anastomoses The ethmoidal nerve sometimes divides into an anterior and a posterior trunk, the latter of which passes through the internal and posterior orbitar foramen, and remains in the nasal fossa. (2) The infra-trochlear or external nasal nerve ( N . infra-irochlearis), advances below the rectus and obliquas superior oculi muscles, along the inner wall of the orbit, passes directly below the pully, and gives off a small filament to the mucous bursa in this place, leaves the orbit, and divides in the internal angle of the eye into two principal branches, a superior and an inferior. These branches soon subdivide into twigs by which the nerve is distributed in the tunica conjunctiva, the caruncula lachrymalis, the lachrymal sac, the orbicularis palpebrarum and the frontalis muscles, and the skin of the back of the nose. It anastomoses above with the supra-trochlear nerve, then with some filaments of the facial nerve, and farther forward with the second branch of the fifth pair. Sometimes the long root of the lenticular ganglion does not come from the nasal nerve, but from the third pair. Analogous to this arrangement but much more rare is the case where the nasal nerve comes from the sixth(3) and not from the fifth pair. 2d. The frontal branch or nerve (N. frontalis ), the largest of the three branches of the ophthalmic nerve, proceeds between the other two from behind forward and from without inward on the levator palpebræ superioris muscle directly below the arch of the orbit. It is at first intimately united with the superior motor nerve. At about its centre it sends off inward and forward a small branch which anastomoses with the infra-trochlear nerve, and which sends filaments into the frontal sinus, either directly, or indirectly by a small ganglion. It then sends off a larger filament, the supra-trochlear nerve (N. supratrochlearis ), which proceeds along the internal wall of the orbit, passes above the pully of the obliquus major muscle, and emerges from the cavity of the orbit. This nerve, called also the internal frontal nerve, is reflected from below upward, distributes its twigs in the corrugator supercilii muscle, the internal and upper part of the orbicuaris palpebrarum, the frontalis muscle and the skin which covers it, and anastomoses with some filaments of the infra-trochlear and the proper frontal nerve. The continuation of the trunk, the proper frontal nerve, gives off no branch within the orbit, leaves this cavity sometimes in one root but sometimes divided into several, through one or more supra-orbitar foramina, is soon reflected from below upward on the upper edge of the orbit, and is distributed in the skin of the forehead and the vertex. 3d. The lachrymal nerve, (N. lachrymalis) which is between the other two in size, and is the most external of the three twigs of the first branch of the fifth pair, goes forward and outward, being also situated against the orbitar plate, and soon divides into an external and an internal branch. The external reunites with a twig of the subcutaneous malar nerve, which comes from the second principal branch of the fifth pair. From this trunk we generally see a filament depart which is sometimes double, and which passing directly to the anterior extremity of the inferior orbitar fissure, between the malar and sphenoid bones, goes outward in the temporal fossa, where it anastomoses with a malar branch of the facial nerve, more rarely with the superficial temporal nerve which comes from the second principal branch of the fifth pair.(l) with each other like a plexus, and enter the lachrymal gland. These twigs are not distributed entirely in the gland. Some, after passing through it, come outwardly, where they are distributed, partly in the external part of the orbicularis palpebrarum muscle, partly in the integuments of the malar region, and anastomose with some filaments from the posterior branches of the facial, the frontal, and the subcutaneous malar nerves. § 1871. The second principal branch of the fifth pair, the middle branch, the superior maxillary nerve (R. quinti paris secundus, s. médius , s. JV. maxillaris superior), (3) is between the other two in its situation and volume. It arises from the anterior part of the gangfionnary plexus ; it goes almost directly forward, or at least a little oblique from below upward, gives off no branch within the skull, although it sometimes anastomoses there with a filament of the ganglionnary nerve, (4) and emerges from this cavity outward and forward through the great foramen rotundum of the sphenoid bone. It is flat, but after emerging it becomes round. Some distance from the place where it leaves the skull, the superior maxillary nerve gives off a small branch, the subcutaneous malar nerve (JV. subcutaneus males), which reascends in the spheno-maxillary fissure. This branch enters into the orbit below the rectus externus oculi muscle, and anastomoses by one or more filaments with the external twig of the lachrymal nerve. It sends off, farther forward, one or more ramifications, which enter into the lachrymal gland ; some of them remain in its tissue, while others, after passing through it, emerge from the orbit and are distributed in the orbicularis palpebrarum muscle and the skin of the cheek, where they communicate with some filaments of the facial nerve and of the third principal branch of the fifth pair. Finally, the subcutaneous malar nerve emerges from the orbit through the malar foramen, sometimes in one trunk, and sometimes divided into several filaments. It is distributed on the face to the lower part of the orbicularis palpebrarum muscle, and also to the skin of the malar region, and communicates with the twigs of the facial and infraorbitar nerves. The superior maxillary nerve then divides into two much larger and nearly equal branches, which proceed almost directly from above downward. They are the pterygo-palatine and the infraorbitar nerves. The jjter'ygo-joalatine nerve ( JV. pterygo-palatinus ) sometimes forms a single trunk, sometimes arises by two or three distinct filaments, winch become the roots of a small rounded triangular or cordiform ganglion, situated on the outside of the spheno-palatine foramen, and termed from its discoverer, the ganglion of Meckel (G. .Meckelii),(l) and also the spheno-palatine ganglion (G. spheno-palalinum). The recurrent and palatine nerves come from this ganglion. If it exists, the upper anterior nasal nerves partially arise from the trunk of the pterygo-palatine nerve, partly from the palatine nerve, and the naso-palatine nerve comes from the pterygo-palatine. First arises a filament which enters the sphenoidal sinus, or which, when it is very much developed, passes through this cavity and goes to the external motor nerve, with which it anastomoses ;(2) sometimes it sends ramifications to the sphenoidal sinus, and also to the posterior and most superior part of the septum of the nasal fossæ. Next come four or five filaments which are a little larger; they pass through the dura-mater, which is extended on the pterygo-palatine foramen, are distributed in the mucous membrane which lines the posterior part of the upper and middle turbinated bones of the nose, and anastomose with the ramifications of the olfactory nerve. They are the upper anterior nasal or the spheno-palatine nerves (N. nasales superiores et anteriores). Farther on are the nerve of the septum , which will be described more properly after the naso-palatine nerve, and the (1) J. F. Meckel, Observation anatomique sur un nœud ou ganglion du second rameau de la cinquième paire des nerfs du cerveau nouvellement découvert avec l’examen physiologique du veritable usage des nœuds ou ganglions des nerfs ; in Mém. de Berlin , 1749. p. 84, 103. tab. iii. palatine fossa, into a recurrent and a descending branch. The recurrent branch, the pterygoid or vidian nerve (JV. quinti recurrent;, s. anastomoticus, s. pterygoideus , s. vidianus ), is so termed from its direction ; for it goes backward, enters into the pterygoid foramen, and anastomoses by several filaments with the facial and great sympathetic nerves. This nerve gives off first inward and downward, two or three filaments termed the posterior and superior nasal nerves (JV. nasales posteriores superiores ), which sometimes unite in a small trunk, termed by Bock, the pharyngœal nerve (R. pharyngœus). These nervesemerge sometimes through the lower part of the spheno-palatine foramen, sometimes pass through the inner wall of the pterygoid canal, penetrate inward through the pterygoid process, and are distributed in the posterior part of the mucous membrane of the nose, where they anastomose with the ramifications of the olfactory nerves in the muscles of the velum palati, the skin of the soft palate, and around the anterior orifice of the Fallopean tube. * The external part of the nerve which is remarkable for its softness and reddish color, then divides, before leaving the pterygoid canal into two branches, which sometimes remain distinct to the ganglion, and by which it terminates. These two branches are the anastomotic nerves. The smaller superior or superficial nerve is the superficial petrous nerve (JV. petrosus superficialis) . It proceeds generally single, seldom divided,, through the fibro-cartilage, situated between the sphenoid bone and the petrous process, goes backward, upward, and outward, under the third principal branch of the fifth pair, in a groove on the upper face of the petrous process, leaves this groove and enters the Fallopian canal, anastomoses here with the facial nerve which passes through it, and sometimes sends filaments to the branches of the ganglionnary nerve which surround the upper part of the carotid artery like a plexus.(l) The inferior or deep, the larger, proceeds in the same direction as the recurrent nerve, emerges from the posterior extremity of the pterygoid canal through the fibro-cartilage, between the sphenoid bone and the petrous process, goes outward and backward, passes through the dura-mater, and goes into the carotid canal, where ii anastomoses with the upper extremity of the ganglionnary nerve, conjointly with a filament of the sixth pair, thus forming a very constant and very evident anastomosis between the fifth pair and the great sympathetic nerve. The differences sometimes observed in this respect will be more in place in the description of the great sympathetic nerve. In fact, it is probably more correct to consider the deep branch of the recurrent nerve as a ramification of this latter. The descending branch or the palatine nerve ( N . palatinus ) is much larger than the recurrent, and is distributed to the middle and lower part of the mucous membrane of the nose, and also to the membrane of the palate. It is then more properly termed the naso-palatine nerve ( N . naso palatinus.) From this, or from the spheno-palatine ganglion, or finally from the trunk of the pterygo-palatine nerve, arises first the nerve of the septum of the nose (iV. septi narium ), which Scarpa(l) less properly terms the naso-palatine nerve (N.naso-palatinus).( 2) This nerve enters the nose with the anterior and superior nasal nerves, through the spheno-palatine foramen, proceeds from without inward, passing before the sphenoidal sinus towards the septum on which it descends from behind forward, between the periosteum and the mucous membrane, to the anterior palatine foramina, farther forward on the left than on the right side, and thus arrives at the membrane of the palate. In passing through the palatine canal the nerves of the two sides unite, sometimes form a small prominence termed the naso-palatine ganglion ( G. naso-palatinum ), and expand on a prominence situated below the anterior palatine foramen. The palatine nerve then divides into a large anterior branch, the continuation of the trunk, and two or three smaller and posterior, all of which descend into the pterygo-palatine fossa. These branches are the great and small palatine nerves ( N . palatini major et minores). They sometimes arise directly from the ganglion, or even, as is true particularly of the smallest, from the second principal branch. The posterior middle nasal nerve soon divides into two branches, which are sometimes separate at their origins. The superior goes directly forward in the mucous membrane of the middle turbinated bone. The second goes to the upper part of that of the inferior turbinated bone. The posterior inferior nasal nerve arises much lower, opposite the posterior extremity of the lower turbinated bone, towards which it proceeds directly, and sends its filaments into the mucous membrane which lines the inner face of this bone anteriorly. The anterior branch of the great nasal nerve sends directly back, ward a small twig, which passes through the pterygoid process in a special canal, and is distributed to the glandular substance of the soft palate. The branch, the fasciculi of which separate from each other, goes forward and downward in the pterygo-palatine canal, and comes through the posterior palatine foramen to the lower face of the bony palate, where it immedia.tely divides into three or four considerable branches which proceed between the mucous membrane and the periosteum, along the inner face of the alveolar processes opposite the teeth, and are distributed in the gum. The two or three small palatine nerves descend behind the great palatine nerve, first in the pterygo-palatine fossa, then lower in small special canals of the petrous portion of the temporal bone, on emerging from which, they enter into the amygdalæ, the palatostaphylinus muscle, the muscular and glandular substance of the soft parts of the palate and the uvula. § 1872. The infraorbitar nerve ( N . infraorbitalis ), the second of the two branches in winch the superior maxillary nerve divides, is directed from behind forward, from within outward, and from above downward, in the spheno-maxillary fissure, and goes to the infra-orbital canal. But before entering into this canal, it sends off a considerable branch called the dentar or posterior superior alveolar nerve ( R. dentalis, s. alveolaris posterior superior). This nerve divides sometimes even at its origin, sometimes afterward, into two branches, an anterior which is smaller, and a posterior which is larger. The posterior descends on the posterior part of the external w7all of the maxillary sinus, below the temporalis muscle, which enters into this cavity through its posterior wall, is distributed in its mucous membrane, ( 1) and there anastomoses with the anterior dentar nerve. It terminates by some superficial ramifications which go to the buccinator muscle, and by deeper twigs which enter into small canals grooved in the posterior part of the body of the superior maxillary bone, and penetrates into the roots of the three large posterior molar teeth. Each root receives one of them. We see one of them also between each two molar teeth, which goes into the gum. In passing through this canal it usually gives off, sometimes sooner and sometimes later, several branches, but always one at least, which is larger than the others even when they exist ; these are the anterior dentar nerves ( N . dentales anteriores) which enter into the superior maxillary bone, send some filaments into the nose at the anterior part of the inferior turbinated bone, anastomose by several filaments with the posterior dentar nerves, pass forward on the roots of the anterior teeth, and terminate by ramifications which go to the incisors, the ca- nine, and the anterior molar teeth, and to the gum. Those which belong to theincisors and the canine teeth arise directly from the anterior dentar nerve ; those of the anterior molar teeth from the union of this nerve with the posterior dentar nerve. The infra-orbitar nerve then emerges from the canal through the infra-orbitar foramen, within which it divides into two principal branches, an internal and an external, and sometimes even in all the other subordinate branches. It thus comes on the face, where it divides into a considerable number of ramifications, which terminate in the skin and the muscles of the nose and upper lip, and anastomose with those of the first principal branch of the fifth pair, and also with some filaments of the facial nerve. ferior. 1st. Superior branch. There is usually only one superior twig, the inferior palpebral nerve (N. palpebralis inferior). This nerve, the first given off by the infraorbitar nerve, from which it is sometimes separated even within this canal, and which often emerges through a special foramen situated more internally than the infraorbitar, immediately ascends from without inward towards the lower part of the orbicularis palpebrarum muscle, and divides into an external and an internal twig. The external goes outward towards the external angle of the eye, on the lower part of the orbicularis palpebrarum, and gives off filaments to this muscle. It anastomoses with those of the internal twig, and with the temporal branches from the facial nerve. The internal goes to the inner angle of the eye, gives a twig to the skin of the nose which descends to the end of this organ, where it anastomoses with the nasal twig of the first principal branch of the fifth pair. It afterwards anastomoses in the lower eyelid with the external twig and with a filament of the infra-trochlear nerve, and terminates in the orbicularis palpebrarum muscle, the integuments of the lower eyelid, the caruncula lachrymalis, and the lachrymal sac. 2d. Anterior or nasal twigs. The twigs which go forward, and also at the same time a little outward, are the superficial or cutaneous nasal nerves ( N . nasales superficiales), which may be distinguished into an internal superior , and an external inferior. The internal superior , generally the smaller, is reflected upward under the levator palpebræ superioris muscle, often gives origin to the preceding, and then divides into two or three filaments which proceed forward below this muscle along the centre of the nose, send their ramifications into the levator labii superioris alæque nasi, and the depressor alæ nasi muscles, and the integuments of the middle and inferior parts of the nose. They extend to the back and tip of this organ, and anastomose in the latter place with the nasal twig of the first principal branch of the fifth pair. The external and inferior descends under the levator labii superioris muscle, often sends an ascending filament to the lower eyelid and to the lower part of the orbicularis palpebrarum muscle, then continues its course from above downward, often receives a filament from the preceding, goes forward to the ala of the nose above the levator labii superioris aloeque nasi muscle, sends ramifications to this muscle and to the middle and upper parts of the orbicularis oris, and terminates at the lower part of the septum and of the top of the nose, where it anastomoses with the nasal twig of the first principal branch of the fifth pair. 3d. Descending or labial tu-igs. The descending twigs are generally three or four superior labial nerves (N. labiales superiores ), they succeed one another from before backward. They are distinguished into internal , middle , and external. All descend from before backward, covered by the levator labii superioris muscle, are distributed in this muscle, the skin of the upper lip, the corresponding part of the orbicularis oris, and the lower part of the zygomatici and the buccinator muscles. They even penetrate through the orbicularis oris muscle, and go to the buccal membrane and the glands of the upper lip. 3d. We frequently find also an external twig of the infraorbitar nerve, the external palpebral nerve. This very small twig passes through the levator labii superioris muscle, goes outward, where some of its filaments are distributed in the orbicularis palpebrarum muscle, and others anastomose with filaments of the facial nerve. § 1873. The third principal branch , the inferior or posterior branch of the fifth pair, the inferior maxillary nerve (22. quinti paris tertius , s. inferior , s. posterior, s. nervus infra-inaxillaris),( 1 ) which is by far the largest, arises from the lower and posterior part of the ganglionnary plexus, and is formed principally by the small anterior portion, whence Palletta(2) considers it a distinct nerve. It is the shortest of the three within the skull, and goes from above downward, and slightly also forward and outward, and enters the round foramen of the sphenoid bone, after anastomosing hi this course with some inconstant filaments, with the cavernous ganglion of the sympathetic nerve. (3) The inferior maxillary nerve is distributed to the muscles, the integuments, and the teeth of the lower jaw, the lower lip, the lower salivary glands, and the tongue. It is covered where it emerges from the cranium, by the pterygoideus externus muscle, and soon divides into two large branches, an upper and anterior, and a lower and posterior. This bifurcation however is § 1S74. The upper anterior branch is much smaller than the other, divides soon after and even before emerging from the skull, into live twigs, which separate from each other like rays. They are the masseteric., the internal and external deep temporal, the buccal and the pterygoid nerves. The masseteric nerve {N. massetericus ), the most external, which generally arises the highest, pursues a transverse direction from within outward, directly before the articular surface of the temporal bone, on the outside of the pterygoideus externus muscle, where it sends filaments to the ligaments of the temporo-maxillary articulation, and to the lower part of the temporalis muscle, then descends from within outward between this muscle and the pterygoideus externus muscle, goes to the sigmoid fissure of the lower maxillary bone, and passing behind the tendon of the temporalis muscle, glides between the two layers of the masseter, in which it is almost entirely distributed. The second twig, the external deep temporal nerve (N. temporalis profundus externus ), arises farther forward and inward, often comes from the preceding or from the buccal nerve, and sometimes from a common trunk with the following. It goes outward under the pterygoideus externus on the temporalis muscles, commonly anastomoses with the following and by an intermediate filament, and goes immediately upward and inward to enter the temporalis muscle. The third twig, the deep internal temporal (N. temporalis profundus internus), is generally larger than the preceding, and follows the same course. It is distributed also in the temporalis muscle, but also sends some anastomotic filaments to the buccal nerves. It also gives off others farther forward which go to anastomose with the cutaneous malar and with the lachrymal nerve on the outside of, and sometimes even within, the orbit : the existence however of these last two anastomoses has been doubted, since the researches of Bock, who regards the filaments generally considered as such, as ramifications of the arteries.(l) The fourth twig, the buccinator or buccal nerve ( N . buccinatorius ), is usually the largest of the five, and sometimes the trunk of the three preceding. It goes forward between the two pterygoidei muscles and through the external, sends filaments to these two muscles, particularly the externa], arrives at the lower part of the temporalis muscle, then descends between this latter and the pterygoideus externus, comes on the external face of the buccinator, is distributed mostly to this muscle, passes through it to send some filaments to the membrane and to the buccal glands, anastomoses with the anterior branches of the facial nerve, and terminates in the levator and depressor anguli oris muscles. The fifth twig, the pterygoid nerve (N. pterygoidens), is the smallest. It arises from the inner part of the superior branch, passes between the pterygoideus extemus and peristaphylinus muscles and arrives at the upper part of the pterygoideus internus, to which it is entirely distributed. § 1875, The posterior and inferior branch is much larger than the preceding and the proper continuation of the trunk, divides soon after arising into three twigs, the superficial temporal , the inferior dentar, and the lingual nerve. The superficial temporal nerve (JV. temporalis superficialis ) most generally arises by two more rarely by three roots, and still more rarely by one. Of these two roots, the inferior, the smaller, comes from the inferior dentar nerve and reunites with the superior, so that the spherospinous or middle cerebral artery passes between them. The trunk goes from within outward on the inside of the temporomaxillary articulation between the condyle of the jaw and the lateral ligament, and here divides in five or six branches. Two or three of these branches penetrate from without inward and from behind forward in the parotid gland, and anastomose with this trunk and with some ramifications of the facial nerve. One or two of the others, which may be termed the nerves of the external auditory passage (N, meatus auditorii externi inferior , s. superior ), go backward, pass through the anterior wall of the osseous portion of the auditory passage, and pass between this and the cartilaginous portion; Their ramifications are distributed some in the integuments of the inner part of the external ear, and others in those of the auditory passage. We see also one of them which goes to the membrane of the tympanum, glides between its two layers, and anastomoses by one or two filaments with the cord of the tympanum.(l) The last and largest branch of the superficial temporal nerve passes through the parotid gland to the external ear, and terminates in the integuments of the central part of the cranium by anastomosing with some filaments of the great occipital and the frontal nerve of the first principal branch of the fifth pair. It also communicates with some filaments of the external lachrymal twig and of the cutaneous malar nerve which go outward. trunk. The inferior dentar nerve ( N . alveolaris maxillœ inferioris, N. maxillaris inferior ), which is situated between the other two twigs of the posterior branch which is generally the largest ramification given off by the trunk of the inframaxillary nerve, sometimes arises by two roots which embrace the internal maxillary artery. It descends from within outward and from behind forward, first between the two ptery- goidei muscles, then between the external and the condyle of the jaw. Near its origin it gives off a small and very constant branch, the mylohyoid nerve (N. mylo-liyoideus ), which descends from behind forward in a channel grooved in the inner face of the branch of the jaw, sends a twig to the submaxillary gland, goes towards the lower face of the mylo-liyoideus muscle, proceeds from behind forward between this muscle and the anterior belly of the digastricus, gives some filaments to both of them but particularly to the mylo-hyoideus muscle, and after being reflected from below upward on the lower edge of the lower jaw, is distributed in the muscles of the chin. The trunk of the inferior dentar nerve proceeds from behind forward in the inferior dentar canal. But it generally divides on entering into two branches, a superior which is smaller, the dentar nerve ( N . dentalis ), and an inferior and larger, the mental nerve {11. mentalis ) ; these proceed at the side of each other, and communicate by numerous anastomosing filaments. The dentar branch is situated below the teeth, and sends a filament to each of them and to each root of the molar teeth. All these filaments arise farther back than the teeth to which they proceed : between each two teeth it sends a filament to the gum. It soon divides under the levator anguli oris muscle into two twigs, the inferior labial nerves (N. labiales inferiores ), the internal of which is larger in a greater or less degree than the. external: The direction of the external is upward ; it sends some filaments to the levator anguli oris muscle, but principally to the lower part of the orbicularis oris, the glands of the lower lip and the buccal membrane, and anastomoses with some filaments from the inferior branches of the facial nerve. The internal , covered by the depressor labii inferioris muscle, goes forward and upward, sends filaments to this muscle, to the levator menti, the central part of the orbicularis oris, the skin of the chin, the glands of the lower lip, and the buccal membrane, and anastomoses with the marginal branch of the facial nerve. The lingual nerve ( N . lingualis , s. gustatorius ), the most anterior of the three twigs of the lower and posterior branch of the inframaxillary nerve is between the other two in respect to size. It arises farther inward than they, and is frequently united to a considerable extent in a common trunk with the preceding. It descends with it from behind forward, usually on the inside of the internal maxillary artery, separates from the inferior dentar nerve and goes inward, receives before the palatostaphylinus and pterygostaphylinus muscles, and behind the pterjrgoideus externus, the cord of the tympanum, which unites with it at a very acute angle, then passes before the inferior dentar nerve, sometimes sends to the pterygoideus internus muscle a filament which is often detached above the anastomosis with the cord of the tympanum, enters between the pterygoideus internus and the ascending branch of the jaw, and passing above the submaxillary gland, gives to it as high as the angle of the jaw several considerable filaments, which come sometimes directly from its trunk, sometimes from a small ganglion which it forms on it, and which is called the maxillary ganglion ( ganglion inaxillare.) These filaments are distributed principally in the gland. Generally however one of them emerges from it, descends on the hyoglossus muscle, anastomoses with a branch of the lingual nerve, and terminates in the genio-glossus muscle. The trunk of the lingual nerve then goes forward between the hyoglossus and mylo-hyoideus muscles, passes between the sublingual gland and the hyoglossus muscle having before it the excretory duct of the submaxillary gland, anastomoses by several considerable filaments which come from its inner side with the hypoglossal nerve, sends some which are very minute to the buccal membrane and larger ones to the sublingual gland, and divides into seven or eight branches which proceed from behind forward and from below upward between the styloglossus and genio-hyoideus muscles. These branches separate like the sticks of a fan, and go principally to the edges and tip of the tongue and are there distributed by minute filaments in the skin of this organ. § 1876. N. patheticus) ,{l) the smallest cerebral nerve, generally arises by an anterior and a posterior root, each composed of one filament about the same size. They are frequently half an inch apart, but united by cellular tissue. They arise directly behind the external half of the posterior part of the tubercula quadrigemina from the anterior and external part of the upper face of the cerebral valve, so that the anterior arises from some transverse medullary fibres which cover the valve in this place, and which unite them on the median line with those of the opposite side. This nerve seldom has three roots and still more rarely one only. After arising, it goes downward and a little forward, first on the upper extremity of the anterior prolongations of the cerebellum, then about two lines from the anterior edge of the occipital protuberance, first on the lateral and then on the lower face of the cerebral peduncle. After proceeding much farther within the skull than any other encephalic nerve, it comes to the posterior clinoid process. There it enters into a special canal of the dura-mater, the internal wall of which is very thin and separates it from the cavernous sinus, usually anastomoses there with the first branch of the trifacial nerve by a small fila- ment, and is situated first below the common motor and the ophthalmic nerves. At the sphenoidal fissure it is situated above the first of these two nerves, enters into the orbit through the upper and internal part of this fissure, and its direction there is from behind forward and from without inward directly under the periosteum, attended by the frontal twig of the ophthalmic branch of the fifth pair, and enlarges much in this course. Finally it enters the obliquus oculi superior muscle at about its centre. X. COMMON MOTOR NERVE. § 1877. The common motor nerve, the common motor of the eye, the third pair, the common oculo-muscular nerve (N. oculo-muscularis inferior, s. médius, s. oculo-motorius communis, s. par tertium),{\ ) a considerable trunk generally the fourth in size and rarely the third among the encephalic nerves, arises about two lines before the anterior edge of the annular protuberance on the inner face of the cerebral peduncle about two lines above its lower edge, at the place where the gray cribriform plate which covers the inner face of the peduncle commences. It even arises in great part from this layer. Some smaller filaments coming from near the internal edge of the lower face of the cerebral peduncle usually join this root, which is single and very large. It is however easy to follow the origin of the nerve farther upward and backward, for beyond the point where it leaves the annular protuberance it is covered anteriorly only by a very thin layer of gray substance of which we perceive no trace posteriorly. When this substance is removed, when the annular protuberance is divided, turned from above downward, and carefully cut longitudinally on the median line, we observe that a medullary layer commences at the place where the nerve emerges, continues with its fibres, and terminates like a fan upward and a little forward, forms a fasciculus which is rounded posteriorly although straight at first, and curves from below upward. The anterior and flat part of this layer extends to the bottom of the groove existing between the two cerebral peduncles. Its posterior parts are arranged in fasciculi, converge from before backward, and are blended at their posterior part. The anterior part, is loose, but in order to see the posterior we must separate the anterior half of the annular protuberance and turn over the two folds. The posterior part of this medullary layer then rises directly below the floor of the aqueduct of Sylvius. The two nerves are at first attached to each other by their inner faces, so that they slightly resemble the arrangement of the optic nerves. After leaving this point, where they are detached from the encephalon, they proceed from within outward and from before back- ward, arrive at the external wall of the cavernous sinus, are situated within and above the first branch of the trifacial and the superior motor nerves ; then changing this direction below and on the outside of these nerves they pass through the dura- mater which closes the sphenoidal fissure, and enter the orbit with the external motor and the nasal branch of the trifacial nerve. divided into a superior and an inferior branch. The superior , the smaller, goes inward and forward, passes on the optic nerve and the nasal twig of the ophthalmic branch, anastomoses with this latter, sends its twigs into the rectus oculi superior muscle, and passes through it to be distributed in the levator palpebræ superioris muscle. The inferior is much larger than the preceding, and passes below and on the outside of the optic nerve, between it and the rectus oculi inferior muscle. It usually divides into three twigs, an internal , which is larger, which goes to the rectus internus muscle ; a middle , which is shorter, for the rectus inferior muscle, and an external inferior branch, which is the longest and thinnest, and which goes to the obliquus inferior muscle, and the lenticular ganglion. This latter gives off near its origin a short filament, which, situated on the outside of the optic nerve, goes to the posterior extremity of the lenticular ganglion, and forms its short root. This filament is always composed of several threads, arises more rarely from the lower branch, but sometimes also it comes at the same time from the external twig, from the middle, and eveir from the trunk of the lower branch.(l) § 1878. The optic or ocular nerve, the second pair (N. opticus , s. visorius , s. par secundum ), the largest of the encephalic nerves arises by a broad and flat portion from the posterior part of the external face, and also from the upper face of the optic bed and the tubercula quadrigemina. Its anterior part, which is the broadest, leaves the upper face of the optic bed, from the substance of which it is easily distinguished on account of the transverse direction of its medullary fibres, to pass on its anterior and external tubercle. The posterior passes below the posterior and external tubercle, and is attached in this place to the tubercula quadrigemina, particularly the posterior, by a medullary band, which goes forward from these latter, passing below the posterior and external tubercle of the optic bed. Thence the optic nerve proceeds from behind forward and from without inward, and descends on the lower face of the cerebral peduncle, with which it is so closely connected that we must admit that it partly arises from this prolongation, although separated from it in almost all its extent by the pia-mater. It gradually becomes narrower, but thicker and more rounded, and unites at an obtuse angle with that of the opposite side on the median line, on the lower face of the cerebrum, below the floor of the third ventricle. The union is so intimate that the two nerves form only one medullary mass. This mass itself has the form of an elongated square, which differs in different subjects, as is indicated in Morgagni(l) and Wenzel, (2) nor has it always the same volume. (3) It receives above some medullary fibres from the floor of the third ventricle, so that we are authorized to think that the optic nerve partially arises from this point. After this union the two optic nerves separate and go forward and outward. Hence, when we view their place of union and their anterior and posterior parts, they represent the form of an X or of a cross. Thus, their decussation has been termed the intercrossing (chiasma). It is very rare, and perhaps never the case, that the two nerves do not unite, (4) or that by an arrangement, perhaps the opposite of the preceding, a small pointed protuberance comes from the anterior edge of the decussation.(ö) Opinions vary in regard to the manner in which the optic nerves unite. Some assert that they are only fitted to each other,(6) others that they entirely intercross, and that of the right eye, for instance, passes to the left side of the body behind the decussation.(7) Finally, some think that there is only a partial decussation, an intercrossing of most of the fibres, (8) that the external fibres of each nerve are situated on the same side of the body before as behind the decussation, while the internal intercross with the corresponding fibres of the opposite side, and pass to the other side of the body. (9) (6) Gallen, De util, part., lib. x. c. xii. — Also a great number of his successors, mentioned in Nœthig.— Zinn, Desc. oc. hum., Gottingen, 1765, p. 190. — Vicq-d’Azyr, in the Mém. de Paris, 1781, p. 554. — Meckel, in Haller, Grundriss, p. 386. (7) This opinion was supported before Galen, as he refutes it ( loc . cit.) ; those who have defended it since, are cited by Morgagni (Ep. anat.) and by Scemmerring, in Nœthig, loc. cit., and Denksder Münchner Akad.. 1808, p. 60. 3d. That where the optic nerve wasted after the loss of an eye, the change in the texture was seen only in the nerve of the same side, behind the decussation, (3) and that it is very easy to distinguish in this latter the two nerves from each other, by their color and other properties.(4) 2d. Those cases where the origin of one optic nerve, or the part of the two nerves behind the decussation has been found unusually large or small, and the nerve of the opposite side presented the same character before the decussation, (6) while the sight was unaffected. 3d. The cases in which the disease of the nerve before the decussation extended behind it only to the .nervous cord of the opposite side, and affected even the corresponding cerebral portions of this side.(7) 4th. The analogous cases where the origin of one of the two nerves was affected, and the functions of the eye of the opposite side were deranged.(8) Sometimes only this origin was diseased, and not the portion of the nerve on the other side of the decussation. (9) 5th. The analogy with several animals, particularly with most fishes, the nerves of which evidently intercross and enter each other. The third hypothesis is supported, (1) Vicq-d’Azyr, loc. cit. — Wenzel, p. Ill, 115. This anatomist admits that a small portion of the inner part proceeds to the opposite side before they unite ; but as he expressly remarks that he has been unable to discover any fibre in this internal part, the preceding' sentence does not favor the decussation, since the direction he allows to the fibres is only that of the whole nerve. — Caldani (Mem. delle soc. ital., vol. xii. part ii. p. 28) has found the optic nerves united behind the decussation by a transverse medullary band. p. 40. (3) Vesalius, loc. cit. — Cesalpino, in Riolan, Anlhopogr ., 1. iv. — Cheselden, in the Phil, trans. — Santorini, Obs. anat., c. iii. p. 63, 64. — Meckel, in Haller, Grundriss , p.386. — Caldani, Opusc. anat., p. 33 and 35: two cases. — Id., ' in Mem. delle soc ital., vol. xii. plate ii. p. 27.— Burns, Anatomy of the head and neck, Edinburgh, 1811, p. 359. (10) Caldani, Opusc. anat., p. 37. tab. ii. fig. 4. The simple maceration in water, or immersion in sulphuric acid and vinegar, gave no result ; but this is not the case with nitric acid after the neurilemma was removed. Caldani has observed, eight times in this manner, that the external nervous fibres went directly to the eye of the same side, and the internal to that of the opposite side, that consequently these latter intercrossed, and that even the fasciculi visibly divided into several branches. 2d. By those pathological cases where one eye being destroyed and its nerve affected, the external fibres of the diseased nerve and of the healthy nerve, remained each on their side before and behind the decussation, while the internal fibres of the healthy eye passed through it to go to the opposite side, where they formed the internal fibres of the nerve of this side, and the internal fibres of the diseased nerve also passed to the healthy side, although less evidently, at least in some cases.(l) 4th. By the cases of the loss of an ej'e with the affection of only one optic nerve before the decussation and of the opposite nerve, or of both, behind this point. (3) This fact really seems to favor the hypothesis of a partial decussation, since different physiologists think it cannot be explained otherwise, and more so, because in many cases where the two nerves were wasted behind the decussation, that of the healthy eye was found unusually large. (4) When all these pathological facts are duly considered, we must admit that they do not prove positively either of the three opinions, inasmuch as the dissection of the healthy parts has not demonstrated the fact of the decussation. In fact., they may be explained satisfactorily by saying that the substance of the two nerves is so blended in the decussation, that these nervesdonot partially or wholly cross, and still less are they placed one against the other, but they properly arise from this common substance formed by the union of the two optic bands ( tracius optici ), which opinion differs much from that of a partial decussation. The differences of the pathological phenomena, authorize the adoption of this hypothesis, as this alone explains them very well. We may then consider as accidental, that where the optic nerve is diseased to the decussation, the alteration is observed on the other side of this union, on the cord of the same side, on that of the opposite side, or on both at once. This intimate union of the two portions of the optic nerves between their origin and decussation, is rendered very probable by what we have remarked, and which had been seen before us by Morgagni, (5) Michaelis, (6) Bichat, (7) and Wenzel, (8) that when the optic nerve had wasted and had been gray for a long time Wenzel has once found in a subject whose sight was not affected, some gray substance in the centre of the decussation ; the interna) fibres of the two nerves evidently passed through this substance to intercross (toc. cit, p. 118). either before or behind the decussation, the decussation itself and the portion of the nerve before or behind it, was not in the least abnormal, and when the contrary occurred, the portion separated by the decussation from that first affected by the disease, was always altered much less than this latter. This phenomenon certainly indicates a great difference and a marked distinction between the posterior part of the nerve, including the decussation and the anterior portion, and the more, as when the portion situated before or behind the decussation is diseased, it usually presents the same kind of alteration in all its extent. The differences between the pathological phenomena, mentioned by us above, depend perhaps on primitive differences of structure. This conjecture seems much more probable, as the structure of the nervous system, notwithstanding its great regularity, nevertheless frequently presents, when attentively considered, very great anomalies. It is then possible, that as in other organs situated on the median line, the union is sometimes more, sometimes less intimate, sometimes there is merely a juxta-posidon, and that there are a series of successive states, the first link of which is the case described by Sœmmerring, in Noethig, and the last, that mentioned by Vesalius, although Haller rejects this hypothesis.(l) Finally, the texture of the optic nerve before or behind the decussation, according as the origin of the nerve or the eye are primitively affected, proves nothing in favor of either of these three opinions, since in some cases where the sense of vision was lost in both eyes at the same time, one of the nerves was much thinner than the other behind the decussation.(2) Finally, according to our own observations, this partial decussation is very probable; some at least of the differences in the pathological phenomena may then be easily explained, since, when the inner part of the optic nerve is affected, that of the opposite side, and when the outer part is diseased, that portion of the same nerve behind the decussation presents marks of disease. § 1879. The two optic nerves separate on leaving the decussation, and pass through the optic foramina into the cavity of the orbits. Here they are situated between the recti muscles of the eye, curve and become convex outward. When near the eye they contract very much, pass through the sclerotica and also the choroid membrane, and terminate in the organ, expanding in the retina. They are first covered with neurilemma before the decussation. This membrane has there more firmness than in the other nerves, and penetrates within them, forming distinct sheaths. The optic nerves differ from all others, not only because they reunite, but also because they are intimately enveloped in all their course by a fibrous sheath, which is continuous posteriorly with the periosteum of the orbit and dura-mater, anteriorly with the sclerotica. § 1S80. The olfactory nerve, the first pair, the ethmoidal nerve (N. olfactorius, s. par primum, the caruncula of the ancients, who considered the optic nerves as the first cerebral pair), is situated on the lower face of the hemispheres of the cerebrum, in a groove which is there seen, but a few lines from their inner edge. It goes a little obliquely from without inward, so that the cords of the two sides are separated anteriorly only by the crista galli process. In this course it advances, on the body of the sphenoid bone and the cribriform plate of the ethmoid bone, covered by the pia-mater, which extends like a bridge from one edge of the groove in which it is situated, to the other. This groove, however, is much deeper than the thickness of the nerve, and like all the other anfractuosities of the cerebrum, the pia-mater exactly covers its surface in all parts. The olfactory nerve arises by three medullary bands or roots, from the posterior and inner part of the anterior lobe of the cerebrum, where this latter unites to the posterior lobe. The external band is the narrowest and strongest. Convex posteriorly, concave anteriorly, its direction is from behind forward, from without inward, and from above downward in the fissure of Sylvius, at the union of the anterior lobe with the posterior, proceeds at first almost transversely, then descends nearly perpendicularly, and reunites with the internal root some distance from the posterior extremity of the lower face of the anterior lobe. The middle root, the shortest, and which it is generally more correct to consider only as the internal portion of the external root, arises from the centre of the anterior perforated plate or even directly from this plate by some fibres of which the internal are concave inward and the external are straight. After proceeding from one to two lines, it unites to the external root and gives rise to a common trunk a line and a half large and very broad, the direction of which is oblique from behind forward and from without inward. The internal root is from one to four lines long. It comes from the internal posterior extremity of the lower face of the anterior lobe, proceeds obliquely from above downward, from behind forward, and from within outward, and anastomoses with the common trunk of the others. All these roots are so imbedded in the gray substance that we perceive only their internal faces, and we cannot demonstrate them in every part without separating them by art. Very probably all the gray substance in which they are imbedded should be regarded as a portion of the cerebrum which is connected Avith the origin of the olfactory nerve. This portion is oblong. It is continuous outward with the union of the anterior and posterior lobes, backAvard Avith the anterior perforated or cribriform plate, forward at its outside and inside with two circumvolutions Avliich bound the fis- turned inward and outward, and the upper angle is the most acute. In its whole extent it is very evidently formed of gray and of white substance disposed in longitudinal fibres which proceed at the side of each other and interlace together. Its anterior and enlarged extremity called the bulb of the olfactory nerve (bulb us n. olfactorii), is that part where, proportionally speaking, we find the most of gray substance. lower face. The lower face of the bulb is the only part of the olfactory nerve whence filaments arise. These filaments, each of which is surrounded by a small prolongation of the dura-mater, pass through the openings of the cribriform plate of the ethmoid bone, thus enter in the nasal fossa, and are mostly distributed in the mucous membrane which lines the septum and the turbinated bones. They are distinguished into internal , middle, and external. We shall mention the manner in which they are distributed when describing the organ of smell.(l) GANCLIONNARY NERVE. § 1881. The ganglionnary nerve, the nervous system of the ganglions, the great sympathetic nerve, the intercostal , the trisplanchnir. nerve (N, gangliosus, s. N. sympatheticus magnus , s. intercostalis maximus, s. vertebralis, Lieutaud, s. trisplanchnicns , s. sysiema vitce antomaticœ vegetatives, Bichat, Gall),(l) differs so remarkably from all produced by odors. Magendie, however, refers this function to the fifth pair, which sends so many different twigs into the nose. He rests his opinion on the fact, that the destruction of the olfactory nerves, and even of the anterior cerebral nerves, is not attended with the loss of smell, which, however, is always the case when the two nerves of the fifth pair are divided (Le nerf olfactif est-il l’organe de l’odorat ? in the Journ. de phys. expérim., vol. iv. p. 69). If this opinion be confirmed, the ethmoid nerve does not differ in this respect from the hypoglossal. P. T. (2) Consult. 1st. On this nerve in general : C. Bergen, De nerro intercostali, Erfort, 1731. — A. F. Walter, Programma quo paris intercostalis et ragi corporis humani nervorum et ab ulroque latere ejus obviorum analomen exhibet, Leipsic, 1733, 1735. — J. F. Huber, De nerro intercostali , de nervo octavi et noni paris deque accessorio, Cassel, 1744. — C. C. Schmidel, De nervo intercostali, Erlangen, 1754. — M. Girardi, De nerro intercostali, Florence, 1791. — A. Portal, Description du nerf intercostal dans l’homme; in the Mém. de l’Institut, vol. iv. Paris, au. xi. p. 151, 209, the other nerves and is so opposed to the rest of the nervous system in several respects that it would be more proper not to place it in the same class with the encephalon, the spinal marrow and their nerves, but to consider it as a different but subordinate system. § 1882. This system is formed of numerous ganglions, varying in number and size not only in both sides of the same subject but also in different individuals, and of nervous twigs, some of which unite these ganglions in several different ways, while others are given off to enter the organs. It exists uninterruptedly on the two sides and the anterior face of the vertebral column, along the neck, chest, and abdomen, so that its two halves frequently anastomose on the median line it extends from the base of the skull to the lower extremity of the trunk, and is distributed in the organs of vegetative life. The ganglions of this nervous system divide in respect to their situation and mode of distribution into two classes which comprise, the first the internal or central ganglions , the second the limiting ganglions. The central ganglions are principally situated in the abdomen, around and above the trunks of the large vessels near the principal organs, those which appear most independent in their functions. Several adjacent ganglions are united to each other by larger or shorter filaments, and thus form a plexus whence arise some nerves which go to the organs, also some filaments which anastomose with other similar plexuses. The limiting ganglions are situated on the two sides of the vertebral column in succession. They are fewer in the neck than in the chest and abdomen, and are generally found in the two latter sections of the trunk between each two vertebrae. They are situated behind the serous membranes of the thoracic and abdominal cavities, and anastomose by some longitudinal cords with each other and with the central ganglions by some oblong or transverse fibres, and with most of the nerves of the centre of the nervous system in the Anat. med., vol. iv. — Bock, Ueber das Gangliensystem ; in Abhandlung über das fünfte Nervenpaar , Meissen, 1817. — E. H. Weber, Anatomia comparata nervi sympathetici, Leipsic, 1817. — J. F. Lobstein, De nervi sympathetici liumani fabrica, usu et morbis, Paris, 1823. — 2d. On its origin : D. Iwanhoff, De origine nervorum, intercostal ium, Strasburg, 1780.- — J. Munniks, Observatio qua 'ad illustrandam artem medicam, ostenüitur origo nervi intercostalis , ejusque commercium cum aliis nervis, ab ejus origine usque ad exitum e calvaria , cum autopsia , tum observatis medicis confirmata; in his Observ. var., Groningen, 1805, no. ii. — 3d. On some of its parts : C. T. 1 .udwig, De ple.vibus nervorum abdominalium atque nervo intercostali duplici observationes nonnullœ, Leipsic, 1772. — H. A. Wrisberg, Obs. anat. de nervis viscerum abdominalium partie. I ; de ganglio plexuque semilunari , Gottingen, 1780. G. Walter, Tabulae nervorum thoracis et abdominis , Berlin, 1783. — H. A. Wrisberg, De nervis vise, abdom., part ii., de nervis systematis cœliaci. Sectio 1 ; de nervis gastricis, quee est observationum de ganglio plexuque semilunari continuatio ; in the Syllogc comment., 1800, p. 551, 570. — H. A. Wrisberg, Obs. anat. neurolog. de nervis viscer. abdom., part iii., de nervis systematis cœliaci II ; de nervis hepaticis et splenicis, quœ est observationum de ganglio plexuque semilunari continuatio II, Gottingen, 1808. — 4th. On its functions. Broussais, Réflexions sur les fonctions du système nerveux en general, sur celles du grand sympathique en particulier, et sur quelques autres points de physiologie ; in the Journ. unir, des $c. mêd., vol. xii. nerves by intermediate filaments. Such is the most general view of the ganglionnary nerve which can be presented. The chain of the limiting ganglions and of the nervous cords which unite them have been generally and until lately considered as its trunk and its upper extremity as its origin, admitting that prolongations proceed outward from these two points to the nervous system of animal life, inward to the thoracic and abdominal viscera. But now it is admitted to be more proper to describe first its most internal part, and to conclude with the history of the ganglions which connect it with the nervous system of animal life, and the filaments which establish this communication. I. CENTRAL PORTION. § 1883. The centre of the ganglionnary nerve is formed of several ganglionnary plexuses situated in the cavity of the abdomen, and of the nerves which proceed from them to the organs, and the limiting ganglions. These plexuses considered from above downward are as follow : § 1884. The solar plexus, the semilunar ganglion , the suprarenal ganglion and median plexus ( P . Solaris , Willis, s. G., s. P. semi-lunaris, abdominalis, transversus, communis, cerebrum abdominale ) deserves to be first studied, since from its size, the constancy of its ganglions whence all the abdominal plexuses emanate, and its direct connection with several of the limiting ganglions, it is the real centre of the nerve. artery. The ganglions which unite to form it vary in number and size. We however always find at least two ganglions, a right and a left, which when many exist are always the largest. They are almost semicircular, generally more than an inch long, about half an inch broad in several parts particularly in the centre, and several lines thick from before backward. Their convex edge is turned outward, their concave edge inward. The right is generally much larger than the left, broader in proportion to its length, angular and rhomboidal. It is situated between the ascending vena-cava and the right pillar of the diaphhragm, and the right renal artery and the upper extremity of the right renal capsule. The left., smaller, is proportionally larger and more semicircular ; it is situated between the left pillar of the diaphragm, the pancreas, the splenic artery, and the left renal capsule. mify more or less in their course and frequently anastomose. We usually observe between the two principal ganglions, particularly between their lower extremities in the space between the cœliac and superior mesenteric arteries, two or three which are smaller : these anastomose with each other and with the two larger ones by intermediate filaments, and apparently belong sometimes to the right and sometimes to the left ganglion. Sometimes the principal ganglions instead of being thicker and broader at their centre as is usual, are very narrow there, while they enlarge at their extremities. This arrangement is the first step towards a rare anomaly, where they divide from above downward in a variable number of enlargements which communicate by nervous filaments. The middle enlargements thus formed are generally the largest ; but sometimes although more rarely they are smaller than the superior and inferior, which renders the arrangement of the nerve still more abnormal. The ganglions in the first case are nearer each other than in this latter ; in the latter case they are sometimes united in several nervous filaments interwoven like a plexus. Sometimes from three to eleven small subordinate ganglions form on the outside above and below one or both of the principal ganglions ; from these arise filaments which go to the adjacent plexuses, and also those which assist to form the great splanchnic nerve. The principal ganglion of the same side is more or less enlarged, so that this formation leads still more directly to that where it is entirely divided into a considerable number of smaller ganglions which are nearly equal in size. Of all these forms those where the central portion is most concentrated is evidently superior to the others : they present a very remarkable repetition of the development of the centre of the nervous system of animal life both in the fetus and in the whole series of animals. The whole solar plexus is considerably large and extends longitudinally from the upper edge of the cceliac artery to below the renal arteries, and it is from one to two inches broad. Some nervous filaments proceed directly from its middle and upper part ; they unite to other filaments of the left pneumo-gastric nerve, give rise to the superior coronary plexus of the stomach, stomo-gastrique , Ch. (P. coronarius , s. ventriculi superior , s. minor), which accompanies the superior coronary artery along the small curve of the stomach, extends to the left orifice of this viscus and anastomoses particularly on the posterior face of the stomach with the inferior coronary and the left hepatic plexus, with which it communicates by twigs. The second and largest of these plexuses is termed the hepatic plexus (P. hepaticus). It descends from left to right. One portion, attends the right inferior coronary artery along the great curve of the stomach, where it is distributed and is termed the inferior coronary plexus ( P. coronarius stomachicus inferior) ; the other is larger and. joins the hepatic vessels with which it goes to the liver. It first attends the hepatic artery, but near the sinus of the vena- porta it divides into a right and a left hepatic plexus. The first is larger than the other, and is formed of from six to eight filaments. It enters into the right lobe of the liver and the left goes to its left lobe. Both anastomose with some filaments of the right pneumo-gastric nerve and also form at intervals small prominences in the substance of the liver. Before entering this gland they send some filaments to the pylorus, and also to theduodenal and pancreatic arteries. Independent of these plexuses a smaller one is sometimes detached from the right semilunar ganglion, the filaments of which proceed from behind forward and from below upward in the small lobe of the liver. The splenic plexus (P. splenicus ) arises from the right lower part of the solar plexus and the left semilunar ganglion, the branches of which accompanying those of the splenic artery which they surround pass on the pancreas, send some filaments to this gland, and also to the large cul-de-sac of the stomach, where they form the small inferior plexus of the stomach ( P . ventriculi inferior et minor), and then enter into the substance of the spleen with the branches of the splenic artery. Some branches arise from the lower part of the semilunar ganglions of the solar, the hepatic and splenic plexuses, and unite to form the superior mesenteric plexus (P. mesentericus superior ). This plexus accompanies the trunk and branches of the superior mesenteric artery : its filaments are distributed principally to the small and large intestine, and some enter the pancreas. The upper part of the semilunar ganglions sends off on each side four or five considerable branches which are enlarged by some filaments from the superior mesenteric plexus, descend towards the renal arteries, and interlacing by five or six subordinate ganglions form the renal plexus (P. renalis ) on each side, which give numerous ramifications to the renal capsules and to the kidneys. This plexus communicates upward and outward with the inferior thoracic and the superior lumbar ganglions by twigs, of which the upper unite in larger branches which go separately to the limiting ganglions and the nervous cords by which these latter are united. The same plexus is continuous below with the spermatic plexus (P. spermaticus), which descends along the spermatic vessels, anastomoses with the superior and inferior mesenteric plexuses, gives some filaments to the ureter, and extends in man to the testicle, in the female to the ovary. Some branches arise below from the superior mesenteric plexus, descend before the abdominal aorta, and enter the inferior mesenteric, the left colic plexus (P. mesentericus, s. mesaraicus inferior , s. médius, Vieussens) . This latter, which is smaller than the upper, embraces the inferior mesenteric artery. It contains but a few small ganglions near this artery. On entering the pelvis it divides into two pairs, one the 'proper inferrior mesenteric plexus attends the branches and twigs of the inferior mesenteric artery, and anastomoses with the lumbar ganglion and sometimes also with the anterior branches of some lumbar nerves. The other has a direction outward and downward, is termed the hypogastric plexus (P. hypogastricus, s. mesentericus inferior, s. tertins, s. posterior ), anastomoses with the lumbar and sacral portions of the terminal cord of the ganglionnary nerve like the sacral nerves, and attending the hypogastric vessels is distributed to the rectum and the bladder, and in the male to the prostate gland and vesiculæ séminales, in the female to the uterus and vagina. It also emerges from the pelvis with the external branches of the hypogastric artery. II. LIMITING CORD AND ITS BRANCHES. § 1885. We have already mentioned generally the arrangement of the limiting cord which is situated on the two sides of the vertebral column and the skull. We describe it from above downward, and .commence by the superior cervical ganglion which exists constantly. A. SUPERIOR CERVICAL GANGLION. § 1886. The superior cervical, the olivary or fusiform ganglion (Gr cemicale supreinum, s. olivare, s. fusiforme), one of the largest of those of the ganglionnary nerve, is situated above and behind the angle of the lower jaw, behind the internal carotid artery before the transverse processes of the second and third cervical vertebræ and the rectus capitis major anticus muscle, on the inside of the pneumo-gastric and hypoglossal nerves. It is surrounded by a cellular sheath which em velops also the trunk of the pneumo-gastric nerve. Its form and size vary much. It is almost always oblong, thinner below than above, terminates however also in a point at its upper and fusiform extremity. Sometimes it tends to divide into several ganglions situated successively from above downward. The first degree of this anomaly is a contraction in its centre. Next comes the formation of an upper or lower appendage ; we then observe contractions in two or three points.(l) It does not constantly extend entirely to the carotid canal. Below it usually descends to the third, sometimes however to the sixth cervical vertebra. Generally it is an inch and a half long and its greatest breadth is three lines ; its length however varies from some lines to four inches, but its breadth and thickness are always inversely as its length. I. UPPER BRANCHES. 1 . The superior branch is sometimes although very rarely double, leaves the upper extremity of the ganglion, enters into the carotid canal, and establishes a communication between the ganglionnary nerve and the portion of the nervous system of animal life contained in the skull. It is situated behind the internal carotid artery towards the lower curve of which it usually divides into two nearly equal branches which separate at an acute angle and ascend in the canal before the carotid artery, one being more external than the other. Opinions vary both in regard to their mode of anastomosis and the number of the portions of the nervous system contained within the skull, with which the ganglionnary nerve communicates by these filaments ; these differences in opinion depend partly on the difficulty of dissecting such delicate parts, partly on the varieties in their arrangement. Anatomists vary also as to the point where the ganglionnary nerve -communicates with the two encephalic nerves ; the differences in opinions are but slight and trivial in regard to the external motor nerve ; but they are great in regard to the fifth pair, for it anastomoses according to some with the trunk of this nerve, (4) according to others with one(5) or more(6) or even with all of its branches. Some think ■they communicate directly, (7) others indirectly and by ganglions :(8) the descriptions also of the anastomosis with the sixth pair vary in this last respect. § 1887. The ganglionnary nerve always anastomoses with the sixth pair in the carotid canal by a considerable branch coming from the superior cervical ganglion, which ascends along the internal carotid artery first on the outside and then on its anterior face. (4) Galen, De nervorum origine ; in Op. omn., Venice, Vot. ii. p. 54. — The Arabians and the first Italian anatomists have adopted his opinion. Rau and Valsalva assert that they have sometimes observed this arrang-ement since. (Morgagni, Ep. an. xvi. p. 330.) This branch generally unites to the external motor nerve by a single twig which meets it and is detached at an acute angle from the external and inferior part of the sixth pair during its passage through the cavernous sinus. filament of the external motor nerve bifurcates soon after arising. Sometimes also the anastomosing branch of the ganglionnary nerve within the sixth pair is double, in which case one proceeds on the outside the other on the inside of the internal carotid artery. We frequently and even perhaps always find at the upper part of the carotid canal or in the cavernous sinus, instead of a direct anastomosis, a ganglion situated on the outside of the internal carotid artery called the cavernous ganglion (G. caver no sum). Three or more filaments proceed from the summit of this ganglion to the nerve of the sixth pair . ( 1 ) The anastomosis with the trifacial nerve is always by a filament which goes to the recurrent twig of the second branch of the fifth pair or the vidian nerve. This filament is distributed partly in the carotid artery, partly also emerges from the carotid canal, passes through the dura-mater and enters the pterygoid canal where it unites with the recurrent twig. Thus the branch from the upper extremity of the upper cervical ganglion usually divides into these two filaments, one of which goes to the external motor, the other to the trifacial nerve. dom below and never above it. Sometimes but rarely also the upper extremity of the superior cervical ganglion gives origin to two superior branches, which go one to the external motor the other to the vidian nerve. When this arrangement exists the two anastomotic filaments and the vidian nerve communicate with the external motor nerve. Sometimes also this triple anastomosis does not exist. An analogous case is where either the anastomosing filament which goes to the external motor nerve or that which proceeds to the trifacial or both divide into several filaments, all of which unite in a common trunk to go to the superior cervical ganglion. § 1888. This is the only anastomosis admitted by most authors between the ganglionnary and the trifacial nerves. In fact it is often the only one which can be demonstrated. But the great sympathetic nerve also unites by its upper extremity in another manner, at least sometimes, with the trifacial nerve. nerve and form a ganglion. Others however whose opinions are like the preceding, assert that beside those filaments mentioned, or even if they do not exist, we find a smaller twig coming from the first branch of the fifth pair ; and this unites sooner or later either with the anastomosing filament of the sixth pair, as Petit, (1) Schmidel,(2) and Coopmanns(3) assert, or with the cavernous ganglion. (4) Laumonier, on the contrary, has found coming from the cavernous ganglion, the two filaments which anastomose with the sixth pair and the vidian nerve, and also a third which went to the second branch of the fifth pair, and a fourth to the fourth branch of this same pair.(5) Bock(6) asserts that ten filaments go to the anterior extremity of the trunk of the fifth pair, particularly towards the portion which corresponds to the first branch. All these assertions, however agree, in this, that besides the filament which anastomoses with the vidian nerve, one or more anastomoses exist nearer the origin of the fifth pair with one or several of its three principal branches, or with its trunk : these anastomoses take place by a ganglion, and from this arises the filament of communication with the superior cervical ganglion. (7) We also sometimes find a more indirect anastomosis between the upper extremity of the ganglionnary nerve and the third pair of cerebral nerves, the latter anastomosing with the sixth and fifth in the place where they give filaments, which communicate with the great sympathetic nerve. (8) According to Fontana(9) and Ribes,(10) whose correctness we have partially attested, the ganglionnary nerve penetrates still farther upward and forward, for it sends some filaments from the carotid canal to the pituitary gland,(ll) or to theinfundibulum,(12) and also a fasciculus which accompanies the ophthalmic artery, forms a plexus around the different branches of this vessel, not excepting the central artery of the retina, and anastomoses by a filament with the lenticular ganglion, and gelatinous filaments which united the ramifications of the great sympathetic nerve with the common motor and other nerves; but by examining them with the microscope, he has not found in them the characters of nervous organs. He regards them as cellular tissue extended in filaments. F. T. consequently with the first principal branch of the fifth, and with the third pair.(l). And likewise as there exists also between the lenticular ganglion, the cavernous sinus, and all the ganglionnary system, a constant relation, (2) similar to that between the two ganglions, we consider this small filament with the ciliary nerves which come from it, as making part of the great sympathetic nerve, which supposition seems to us very probable. The external branches are from one to four in number, pass above' the rectus capitis major anticus muscle, to go and meet the first and second cervical nerve. When there is only one, it is larger, and soon divides into as many branches as generally exist, comes sometimes from the upper, and sometimes from the centre of the superior cervical ganglion. The upper two arise from the upper extremity of this same ganglion, directly at the side of each other, and anastomose with the anastomotic plexus of the first and second cervical nerves. The third communicates with that of the third and fourth cervical pairs. The fourth which arises more frequently from the twig of communication between the first and second cervical ganglions, anastomoses on one side by several filaments with the anastomotic plexus of the third and fourth cervical nerves, and is distributed in the rectus capitis major anticus and the scalenus anticus muscle. The internal branches are much smaller and less constant in respect to number, and are distributed to the longus colli, the rectus capitis major anticus muscle, the pharynx and the larynx. The anterior branches are the largest and most numerous. They are distinguished by their reddish tint and their softness, and hence are termed soft nerves ( N . molles ). The superior are shorter than the others, proceed from below upward, and anastomose with the hypoglossal, the pneumo- gastric, and the facial nerves, just after they emerge from the skull. The middle and inferior are larger, go forward' and downward, envelop the primitive carotid arteries to their origin, anastomose in this course with some branches of the pneumo-gastric nerve, and surround also, together with the facial and pneumo-gastrie nerves, the branches of the external and internal carotid arteries, to the carotid canal. The latter not unfrequently come from a distinct small ganglion. The largest anterior branch is the superior or superficial cardiac nerve (JV. cardiacus superior , s. superficialis ), which arises by from four to six filaments from the internal anterior part of the cervical ganglion, sometimes also partially or wholly from the upper extremity of the cord which joins this ganglion to the following. The minute nerve formed by the union of these filaments, descends on the outside of the primitive carotid artery, covered by the cord of communication of the great sympathetic nerve, gives off at about its centre some filaments which surround the inferior thyroid artery, anastomoses with one or two twigs of the pneumo-gastric nerve, communicates also with the descending branch of the hypoglossal nerve, gives ramifications to the pharynx, the esophagus, the sterno-hyoideus and sterno-thyroideus muscles, and usually terminates partly by anastomosing with some ramuscules of the recurrent branch of the pneumo-gastric nerve, and partly sends retrograde filaments to the thyroid gland. It more rarely descends to the arch of the aorta, where it unites to the middle cardiac nerve ; but it never extends to the heart., so that it does not deserve the term applied to it. V. INFERIOR BRANCH. The inferior branch establishes the communication between the superior and the middle, or the inferior cervical ganglion, and is generally considered as the continuation of the trunk. It varies in size and firmness. It is generally thinnest in its centre, and is always larger than the superior cardiac nerve which is situated before and on the inside of it. It constantly arises from the lower extremity of the superior cervical ganglion, with which it is less directly continuous, the larger it is and the smaller the ganglion. Its length depends on that of the superior ganglion, and on the presence or absence of the middle one. It always exists. It is situated before the rectus capitis major anticus and the longus colli muscles, near the inner edge of this latter, first behind the internal carotid artery, then behind the primitive carotid, between the internal jugular vein and the pneumo-gastric nerve. It is most generally single. Very rarely it is divided at its lower part into two twigs, which embrace the inferior thyroid artery, and which usually enter, one the middle cervical ganglion, the other the inferior cervical ganglion. This branch anastomoses by some external filaments with the accessory and several cervical nerves, more frequently with the superior than the inferior, sometimes even with the eighth. These differences and those in the length of the cord, depend on those in the size of the superior cervical ganglion, and also on the presence or absence of the middle ganglion. The anastomosing branches generally unite in some larger branches before coming to the trunk of the ganglionnary nerve. F rom this branch arise some filaments which contribute to form the superficial cardiac nerves. It gives some also which unite to others coming from the superior cervical ganglion, sometimes arise only from the superficial cardiac nerves, and go almost transversely inward, and are distributed, the superior particularly, in the constrictor muscles of the pharynx, the inferior in the thyroid gland, the muscles, and the mucous membrane of the larynx. These filaments frequently anastomose with each other or with some ramifications of the pneumogastric and glosso-pharyngeal nerve. 1839. The middle cervical or thyroid ganglion (G. cervicale medium, s. thyroideum ) is situated at the origin of the inferior thyroid artery, between the fifth and sixth, or between the sixth and seventh cervical vertebrae, directly before the longus colli muscle, behind the primitive carotid artery and the pneumo-gastric nerve. It is not so constant as the superior; it however exists more frequently than it is absent, and in the proportion of 3 : 1, judging from our dissections ; it is sometimes extremely small, and sometimes deficient. It is never oblong, but always broad and slightly flat. When deficient, we sometimes, but not always, find in its place two inferior cervical ganglions, in which case consequently, it is only situated lower than usual. Sometimes, but much more rarely, it is double, that is, it is divided into two small ganglions, a superior and an inferior, the former of which is then situated higher than the common single ganglion. to the sixth. The internal accompany the inferior thyroid artery, on which they give rise to the thyroid plexus (PI. thyroideus ), extend to the thyroid gland, and go to join and enlarge the recurrent laryngceal nerve. The anterior form the middle or deep cardiac nerve, the great cardiac nerve (N. cardiacus médius, s. magnus, s. profundus ), which is the largest. Five or six filaments unite near the ganglion, first into two or three fasciculi, then in a trunk which descends obliquely from without inward, first along the primitive carotid artery, then before the subclavian, anastomoses in its course by several filaments with the trunk of the pneumo-gastric nerve, and with its recurrent branch, and unites with the inferior cardiac nerve to form the cardiac plexus. The middle cardiac nerve differs on the right and left sides. That of the right side, after passing before the subclavian artery, descends along the trunk of the innominata, unites at its bifurcation by a small ganglion with one or two twigs of the pneumo-gastric nerve, the trachea. That of the left side arises by several filaments from the middle cervical ganglion, andfromthe inferior ganglion by one or two filaments which are larger than the preceding. The two ganglions then unite in this place, while on the right side they remain separate. The two roots unite some distance from the origin of the subclavian artery. The trunk passes behind the arch of the aorta, there unites to some filaments of the pneumo-gastric nerve, and anastomoses with that of the right side, and likewise with the two inferior cardiac nerves, to form the cardiac plexus. The inferior branches are very minute, shorter than the rest, and five or six in number. They descend on the right side before and behind the subclavian artery, on the left side before and behind the trunk of the aorta, and anastomose with the superior ascending branches of the inferior cervical ganglion. Sometimes the anterior of these branches are deficient, and the posterior also are united in a short common trunk, which establishes a direct connection between the two cervical ganglions. § 1890. The inferior cervical ganglion (G. cervicale inferius) is much more constant than the central, and is generally flat, rarely rounded and oblong, often very irregular, and sometimes double. It is situated before the transverse process of the seventh cervical vertebra and the neck of the first rib, but sometimes descends to the second rib. Its superior branches anastomose with the inferior of the middle ganglion. One which is rather large, enters the vertebral canal, where it entwines around the vertebral artery, sends some filaments to the intertransversarii muscles, and terminates at the third or second cervical vertebra. mose with the brachial plexus. The external are smaller, but numerous, surround the subclavian artery, and give ramifications to the muscles of the neck, and anastomose with the two or three inferior cervical nerves, and also with the first dorsal, sometimes even but more rarely with the second thoracic pair, when the inferior cervical ganglion is much developed. the pulmonary plexus. The anterior form the inferior cardiac nerve (N. car diacus inferior. s. tertius , s. parvus ), which generally exists only on the right side, while on the left it is only indicated by the inferior root of the great cardiac nerve. These branches frequently interlace before uniting in a single trunk. The latter descends first behind the subclavian artery, then before the innominata and the arch of the aorta, anastomoses often with the pneumogastric nerve, gives some filaments to the vessels situated near its course, and goes to the left between the aorta and the pulmonary artery, and terminates in the anterior cardiac plexus. CARDIAC PLEXUS. § 1891. The cardiac plexus (PI. cardiacus ) is formed principally by the middle cardiac nerves. It is situated between the arch of the aoi ta and the bifurcation of the trachea. It extends from the division of the pulmonary artery to the origin of the innommata. Its anterior filaments go principally to the anterior wall of the aorta, and the posterior to the pulmonary plexus. The inferior are more numerous, and go almost exclusively to the heart, where they form the two coronary plexuses (PI. coronarii ), in which also terminate some filaments of the inferior, and more generally of the superior cardiac nerve. The posterior coronary plexus is much larger than the anterior ; it goes to the base of the heart, descending on the left pulmonary artery. It is distributed to the lower and posterior part of the left ventricle, along the posterior coronary artery and its branches. The anterior follows the course of the left inferior cardiac nerve, in its whole extent, passes between the aorta and the pulmonary artery, and after anastomosing at its upper part with the posterior, attends the anterior coronary artery and its ramifications, on the upper face of the heart and the right auricle, where it frequently anastomoses with the posterior, along the posterior edge of the organ. Some smaller twigs of this plexus proceed on the left pulmonary artery, and go to the pulmonary plexus of the left side. § 1892. We find in the chest between the transverse processes of each two vertebrae, and on each side, a ganglion called the thoracic (Gl. thoracicum). These ganglions are generally slightly rounded, elongated, triangular, and fusiform. They are situated more on the outside than the cervical. The first counting from above downward (G. thoracicum supremum) is the largest of all the limiting ganglions except the superior- cervical. Sometimes it is blended with the second ; this, however, is rare, and even when it appears, generally exists on the outside. The middle ganglions are often a little smaller than the superior and the inferior. filament, rarely by two. The superior is almost constantly attached to the inferior cervical nerve by two filaments, the anterior, of which not unfrequently divides in turn into two smaller filaments. Each thoracic ganglion anastomoses on the outside by two filaments, with its corresponding thoracic nerve. Internally, the superior gives off branches, some of which go to the lower part of the longus colli muscle, others to the cardiac plexus, several to the pulmonary plexus, which, however, is principally formed by the pneumo-gastric nerve ; finally, some .proceed to the aorta. I. SPLANCHNIC NERVE. § 1893. From the inferior thoracic ganglions, and from their filaments of union, generally from the sixth or the seventh to the eleventh, arise cords, the upper of which are usually the largest ; they vary in number from three to seven, and are very rarely the same on both sides of the body ; they unite at an acute angle near the diaphragm, to form the splanchnic nerve, grand surrénal , Ch. (JV. splanchnicus). This nerve descends behind the pleura, and generally goes from the chest into the abdomen, between the inner and middle prolongations of the pillar of the diaphragm, sometimes also through the aortic opening. It anastomoses in the abdomen principally with the semilunar ganglion of its side, sometimes directly, sometimes indirectly, by some small ganglions. It then forms the principle mode of union between the central portion of the ganglionnary nerve and the limiting ganglions. Not unfrequently some of the roots by which it arises, particularly the inferior, go separately to the semilunar ganglion, and some of them often anastomose, not with this ganglion, but with some filaments of the solar, the hepatic, the splenic, and the two renal plexuses, § 1894. Two or three inferior branches, which, however, remain distinct, sometimes unite on the right side more frequently than on the left, in a small special trunk, called the small splanchnic nerve, petit surrénal , Ch. (N. splanchnicus minor.) This trunk passes through the pillar of the diaphragm below the preceding. It is enlarged by some filaments from the superior lumbar ganglions, and goes principally into the renal plexus, which is often in great part formed by it. E. ABDOMINAL GANGLIONS. § 1895. The cord by which the limiting ganglions unite is always very small below the origin of the splanchnic nerve. Sometimes it is entirely deficient in some points, so that the trunk of the great sympa- thetic nerve is there interrupted 1 ) and the limiting ganglions form one and the same series with the abdominal ganglions and plexuses only by intermediate connections. When this series comes on the lumbar vertebrae it goes forward. We there see ganglions which are much smaller, more remote from each other, and less constant in their situation than those hitherto examined. The upper is always larger than the others, which gradually diminish from above downward and often do not exist, or at least are almost invisible. The upper pelvic ganglions of the limiting cord are a little larger than the inferior lumbar, and form a series which converges from above downward. There are usually four or five, the lowest of which is situated forward between the sacrum and the coccyx, and anastomoses with the corresponding ganglion of the opposite side by a shortened thin filament which is convex downward. The lumbar and pelvic ganglions are united by some filaments which differ from those existing between the others in their length and also in their number and size ; for there are usually three or four between each two ganglions, which are much smaller than those between the superior ganglions. from below upward. The middle are transverse, and the superior oblique from above downward. The latter are very long, the first very short. Some which are smaller go upward to the psoas muscle, downward to the pyramidalis and to the levator ani muscles. The lumbar ganglions give off some internal branches which go to the anterior face of the aorta, and contribute to form the aortic plexus which comes from the superior mesenteric plexus. Some of the sacral ganglions anastomose together before the sacrum ; others terminate in the hypogastric plexus. The series of limiting ganglions terminates below in some filaments which radiate from the last of them, and which are distributed in the lower and posterior part of the rectum. § 1896. Our mode of describing the ganglionnary nerve differs from that hitherto adopted even by those anatomists who consider it as ■directly opposed to the rest of the system, for they generally commence by that part which descends along the vertebral column, by the external ganglionnary cord, and terminate with the central portion. (1) This has been seen twice by Haller (Elem. phys., vol. iv. p. 261). Bichat has ■also made this remark (Reck. phys. sur la vie et la mort , p. 82), and uses this as the principal argument in favor of his opinion, that the sympathetic nerve does not form a continuous trunk from the head to the pelvis. Wrisberg ( Obs. anat. de ganglia plexuque semilunari, § 19, in the Comm. Geetting, 1779, vol. ii. p. 102) has admitted this arrangement to be an anomaly, and Weber (Anat. comp, nervi sympathy p. 122 regards this observation as doubtful. In fact the ganglionnary nerve is only the highest development of a form which has passed through several gradations. We may consider the diaphragmatic nerve as the first of these : this arises from several cervical pairs, and passes some distance to go to a voluntary muscle, the diaphragm, the principal agent in respiration. This formation is still more developed in the four posterior cerebral nerves, particularly in the pneumo-gastric, which forms plexiform anastomoses with the superior cervical nerves, descends along the neck, is distributed to the organs of respiration, and descends to the stomach in the abdominal cavity. The whole course of this nerve favors our analogies still more, inasmuch as it forms numerous plexuses whence branches proceed to the organs. The ganglionnary nerve, if we except some filaments which arise perhaps from the pituitary gland, does not commence directly at the centre of the nervous system, but from several of the cerebral and from all the spinal nerves. It descends lower than the pneumo-gastric nerves, gives some filaments to all those organs of vegetative life which receive none from this latter, and frequently anastomoses with the two preceding. The plexiform and ganglionnary structure is more evident in it than in any other nerve, so that even the inner part of its expansion exceeds the outer ; and hence from its form, situation, and connections with the encephalon and spinal marrow, it may be regarded as the trunk of the nerve, as is generally admitted, and thus the inner part is considered the central portion. These are our reasons for departing from the common course, although the anatomical and the physiological relations of the ganglionnary nerve prove that it is dependent on the centre of the nervous system, being connected with it by its outer part. DEVELOPMENT. § 1897. The differences presented by the nerves during their development have been but slightly studied, and we have but few observations which refer to them. Not having had sufficient opportunities of obtaining well preserved human fetuses, we cannot add as many remarks as are desirable to those already existing. faster than the cerebral nerves. We have found them perfectly white and evidently fibrous in the fetus of six months, while the cerebral nerves were gray. The fibrous texture and color are developed latest in the optic nerves. At six months it is much larger than the other encephalic nerves, and even at the ninth month of pregnancy it is still as gray as the rest of the cortical substance, is very soft, and presents no appearance of fibres. We have not yet been ablctD determine if it whitens before birth ; it however experiences this change early, for in two children one month old we have found it perfectly white in all its course, except most of the portion between the decussation and the eye ; the latter was entirely white before the decussation, gray on the outside and white on the inside in the centre ; finally totally gray forward. We may conclude from these facts that the nerves complete their development from within outward and from behind forward. This proposition applies both to the different nerves and to the same nerves in different parts of the body. It is then very curious that the olfactory nerve which is the most anterior remains almost entirely gray during life, and constantly preserves this tint in its whole anterior part. This law seems to be general, for we have since met with it in fetuses of the hog and cat. presented by the nerves : Among the spinal nerves we have found in a great many fetuses the crurai nerve divided on emerging from the pelvis into its tibial and peroneal branches, which were the more distinct the younger the fetys. Before the end of the fifth month of pregnancy they were not united so intimately as they are at an advanced age ; hence this arrangement, which is abnormal in the adult, is normal during the early periods of existence.(l) We have not been able as yet to observe any difference in the other spinal nerves The trifacial nerve differs from what it is in the adult : 1. In the number of its cords, which are at first fewer. In the fetus of eight months there are only eighteen in the large root, while there are from twenty-eight to thirty in a child when bom. (2) These are two remarkable analogies with the mammalia. In the full grown fetus its external root is evidently medullary. We perceive also some medullary striæ on the lower face of the nerve, but there is no trace of the medullary band which represents its internal root. In the early periods of fetal existence the great sympathetic nerve is more developed in proportion to the body than almost any other part of the nervous system. It is very remarkable that the large limiting ganglions are so near each other, particularly in the chest, that they form an uninterrupted series. The splanchnic nerve is also proportionally much thicker than in the adult. 1. BETWEEN THE SPINAL AND THE ENCEPHALIC NERVES. § 1898. The spinal and encephalic nerves are generally strictly opposed to each other, and are distinguished by characters mentioned previously (§ 170) ; but the differences between them are not so distinct as is asserted. First those which truly exist do not prevent us from considering the encephalic nerves in the condition of spinal nerves, and from demonstrating that they are only modifications of the latter, and from investigating the cause of these modifications. All the encephalic nerves are portions of spinal nerves which are not united in a single trunk like the latter, but are developed as so many separate nerves. Tins modification of the primitive type depends on the development of the centre of the nervous system within the skull and on that of the skull itself, which mechanically separates the different groups of the roots of the nerves at their origin and in their course. It also depends on special organs, those of the senses, which are developed in the skull, the roots of which are formed by the nerves that go to them, and which are perfect in the direct ratio of the development of their special nerves. Comparative anatomy demonstrates, at least in regard to several organs of the senses, that new nerves are not formed for them,(l) hut only that single branches arising from a special part of the encephalon become trunks. In fact we see several nerves, especially among those of tire organs of the senses, which form separate trunks in superior animals,- are only subordinate branches in the inferior animals. This is the case particularly with the trifacial nerve ; and this is much more evident the more inferior the animal. This development of portions of nerves which raises them to the rank of distinct nerves is gradually increased from the posterior to the anterior extremity of the cerebrum. It is manifested in the posterior pairs only by the want of union between the anterior and posterior roots ; but the anterior roots seem to be formed from the fact that single fasciculi appear to be the proper nerves. The nervous system then follows precisely the same type as the other systems, particularly the osseous ; for the bones of the skull are more similar to the vertebrae the more posteriorly they are situated, and the dissimilarity between them and the vertebrae which gradually increases from behind forward, depends principally upon the fact that simple portions of the vertebrae have become sufficiently developed to be considered distinct pieces of bone. In this view of the subject, we should consider the last four cerebral pairs, the accessory, the pneumo-gastric, the glosso-pharyngeal, and the hypoglossal nerves, as so many sections of one and the same nerve, the posterior of which is formed by the first three nerves, and the anterior by the fourth. In fact, the accessory, the pneumo-gastric, and the glosso-pharyngeal nerves, arise by an uninterrupted series from the posterior cord of the spinal marrow, and emerge from the skull through the same opening. They thus form in the skull, trunks, the external parts of which are separate from each other, and generally pass through the dura-mater in different points. But this is far from being the case with the accessory nerve, and even when it is, the accessory is adapted to the pneumo-gastric nerve so intimately, that they form a single trunk. Beside, after the two nerves separate, the inner branch of the ' accessory nerve again unites with the eighth pair, and continues with it. The glosso-pharyngeal nerve also anastomoses by one filament even within the cranium, with the pneumo-gastric nerve, and after leaving the skull, they communicate by several other filaments. It is curious that the accessory and pneumo-gastric nerves on one side, the glosso-pharyngeal nerve on the other, and just before where it unites with the two preceeding, form ganglions near the place where they emerge from the skull, exactly as do the posterior (1) See on this subject the important memoir of Treviranus, in which he proves that the nerves of the fifth pair take the place of those of very important sense in some animals, and that there is in these animals some org-ans of sense very different from those of man, the nerves of which are the branches of the fifth pair (Sur les nerfs de la cinquième paire, considérés comme organes ou /conducteurs, de sensations ; in the Journ. oomplém. dessc. méd., vol. xv. p. 207). Ilis observations have been confirmed since by Magendie. F. T. roots of the spinal nerves ; nor ought we to omit mentioning that the posterior root of the superior cervical nerve often joins the accessory, which then assumes the character of the posterior root, which character is also expressed very distinctly by its situation behind the ligamentum denticulatum. The glosso-pharyngeal nerve, the anterior root of this pair of nerves, arises from the anterior cord of the medulla oblongata, like the other anterior roots of the spinal nerves, and as its origin is situated more inward and forward, it also emerges from the skull through an opening situated more inward and forward. In fact, it leaves the skull through a special opening in the occipital bone, rather distant from that through which the other three pass. But this difference from the spinal nerves depend on the two causes mentioned above, and we see in it only a greater development of the arrangement of the anterior and posterior roots of the spinal nerves which pass through distinct openings in the dura-mater before uniting ; finally, the glosso-pharyngeal nerve just after leaving the skull, is adapted directly to the trunk of the pneumo-gastric nerve, anastomoses with it by some filaments, particularly below its ganglion, and goes forward, while the eighth pair, united with the other two, is distributed principally below and backward. We ought not to forget that this nerve never forms the ganglion alone, and rarely or never communicates with the ganglion of the three posterior nerves. The fasciculi of this nerve, like those of the first three, frequently emerge from the dura-mater, and sometimes from the skull, through distinct openings, but this difference is 'not essential, for if the fasciculi of each of the roots of the spinal nerves unite in man before that each root passes through the dura-mater, in the mammalia, they perforate this membrane in three or four points, and before uniting, as is also true of the nerves of which we speak. Comparative anatomy furnishes several other facts which prove the parallel stated by us. In fishes, the anterior and posterior roots of the spinal nerves emerge separately from the spinal column through special openings, so that they are still more similar to the cerebral nerves in this class of the animal kingdom. On the other hand, in most of the mammalia the first cervical nerve, and even the second in some, particularly the hog and the ox, frequently arise entirely from the anterior cord of the spinal marrow, and form only the anterior root of a spinal nerve, which does not emerge through a groove, but through an opening in the first and second cervical vertebræ. In almost all the mammalia the posterior root of the first cervical nerve enlarges into a ganglion long before it unites with the anterior, and’ before the nerve passes through the first cervical vertebra. The ganglion sometimes divides, as we have often observed in the hog for instance, into two enlargements, an anterior and a posterior, or at least we not unfrequently observe a deep strangulation at its centre and the portion of the posterior root between it and the part of the nerve where it emerges from the vertebral column, forms two in the hog, an anterior and a posterior ; f his shows bral pairs. Scemmerring had already remarked that the glosso-pharyngeal nerve appeared at its origin like each of the spinal nerves ; hence, it ought not to be separated from them and be considered an encephalic nerve. (1) The same anatomist compared the origin of the pneumogastric to that of the spinal nerves. (2) Finally, others had considered the accessory as a spinal nerve, or as making the transition from the spinal to the encephalic nerves. But each admits that these comparisons, founded on peculiarities which escape the eye, have no connection with the proposition we establish, viz. that the last four cerebral pairs form in fact only one encephalic nerve, the posterior root of which emerges through the intervertebral foramen, situated between the last and the last but one of the vertebrae of the skull (the occipital and the temporal bones), while the second emerges from it only through the last cephalic vertebra. The reduction of the other eight pairs is more difficult. Some, however, the common and the external motor, evidently have the characters of anterior roots, or at least of portions of anterior roots ~ others, as the auditory and the superior motor nerve, present no less manifestly those of the posterior roots. It is more difficult to determine in regard to the rest. We may, nevertheless, compare the facial with the auditory nerve, and consequently with tho posterior roots, on account of its course and the nearness of its origin, even as the origin and the course of the trifacial nerve authorize us to arrange it along the anterior roots. As to the two anterior pairs, the second may be compared to a posterior root, because it arises from the tubercula quadrigemina and the optic beds, and the first may be compared to an anterior root. We may then consider four pairs as anterior roots, and four as posterior roots, or as portions of these roots. It is now easy to to refer the auditory, the facial, the trifacial, and the motor nerve, to a single trunk. When we follow the origin of the facial, trifacial, and auditory nerves within the cerebrum and backward, we see that they singularly approach each other. In regard to the facial and the auditory nerve, we must mention beside the nearness of their origins, the remark of Santorini, that we can trace below the transverse fibres of the annular protuberance, to the origin of the auditory nerve, some fibres which from their progress and direction, are evidently the commencement of the facial nerve. (3) The trifacial nerve which partly arises from the olivary bodies, blends here with the sixth pair. The common motor nerve goes from before backward to meet all these nerves in the annular protuberance. The superior motor nerve and the optic nerve, are also very intimately united with them by the band which extends from the medulla oblongata to the tubercula quadrigemina. The demonstration is most difficult with regard to the two anterior nerves ; still the short distance between the origins of the external motor and optic nerves, indicate that the latter depends on the others, and the anterior commissure imites the olfactory and the optic nerves. TREMITIES. § 1899. The nerves of the upper and lower extremities, like the bones, the muscles, and the vessels, are formed essentially after the same type, and differ only by slight modifications of this type, which is subject to the same laws as those of the other three systems. At first view the number of the pairs of nerves which unite to form the nerves of the two extremities, seem to differ considerably, as there are but five pahs of nerves of the upper extremities, while those of the lower are formed by ten. This difference, however, vanishes on strict examination. In fact, all the cervical nerves are evidently arranged among those which concur to form the brachial plexus, since they are all united and changed into a real plexus like all the lumbar and sacral nerves, by large anastomoses between their anterior branches. Further, the difference in number between the nerves of the two extremities is only one pair. But we may also explain this apparent anomaly by considering the last four encephalic nerves, the glossopharyngeal, the accessory, the pneumo-gastric, and the hypoglossal nerves as one pair, which corresponds to the branches of the inferior sacral nerves. This comparison is authorized by the discussion in regard to the origin of these four nerves which we have mentioned, and by considering the manner in which they are distributed. In fact, they give off branches to the tongue and -upper part of the intestinal -canal, even as the inferior sacral nerves send them to the organs of generation and to the lower part of the intestinal canal. All these analogies admitted, the number of pairs of nerves in the two extremities is equal : we must not, however, attach much importance to this uniformity of number, nor consume time in endeavoring to establish it, for it is unimportant, but presents itself so naturally, that it would be wrong to neglect it. We may also proceed in an opposite manner, and decompose the superior and inferior plexuses, considering separately the deep cervical and brachial plexuses above, and the lombo-abdominal and sacral plexuses below, and oppose them to each other. This is Bichat’s method. But it is inferior to the other, because it obliges us to separate parts which are united. The superior cervical nerves are distributed to the muscles and integuments of the neck, the same as the superior lumbar nerves are to the muscles and skin of the loins. The first sends some branches to the skin of the shoulder, the suprascapular nerves, while the second furnish some to the skin of the haunch and the arms. The thoracic nerves correspond to the obturator nerve by their high origin, their course .below the bones of the same part, and their distribution to muscles which correspond. The axillary nerve is the inferior gluteal. The nerves which are distributed lower in the two extremities' differ much more, since two twigs and even large branches, which correspond in their mode of distribution, arise from different trunks. The branches, however, are the same, and we can easily explain their differences in respect to origin. The nerves yet to be compared are in the upper extremity, the internal and the external cutaneous nerve, the radial, the median, and the ulnar nerve ; in the lower extremity, the crural and the sciatic nerve. internal cutaneous, the median, and the ulnar nerve, to the sciatic. The external cutaneous nerve and the long cutaneous branch of the radial nerve, are evidently thesuperior and inferior internal saphena nerves of the lower extremity, since they descend along the side of the thumb and of the large toe, which is the internal the the upper limb is in a moderate degree of pronation, and is always so in the lower extremi.y when it is at rest. The muscular branches of the crural nerve are the upper branches of the radial nerve. They are distributed in the extensor muscles of the leg, as the latter are in those of the fore-arm. The analogy, however, between the radial and crural nerves, ceases there. The lower branches given off by the latter are represented in the leg, but come there from the sciatic nerve. The superior and posterior cutaneous nerves of this latter, very evidently correspond to the upper branches of the internal cutaneous nerve of the arm, since they descend on the outer or fibular side of the little toe, as these latter do on the ulnar side of the little finger. The tibial nerve corresponds principally to the median and a part of the ulnar nerve. The peroneal represents the lower part of the ulnar nerve, and still more that of the radial. We may compare the posterior cutaneous branch of the tibial nerve, which so frequently arises from the peroneal nerve, to some ramifications of the internal cutaneous brachial nerve. The cutaneous branch which is distributed in the back of the foot corresponds by its external- twig to the dorsal branch of the ulnar nerve, and by the internal to that of the radial nerve. 1st. As the fibula, from its smallness and its want of articulation with the tibia, seems reduced in man to a simple constituent part of the tibia ; as several muscles of the leg are attached in a common tendon, while others situated hi the fore-arm in the upper extremity are found in the sole of the foot ; as the external cutaneous vein of the pelvic limb unites with the internal at the knee, while these two veins remain distinct to the axilla in the upper extremity ; finally as the arteries often divide very high in the upper extremity, while this anomaly is very rare in the lower, so likewise the nervous trunks which separate very early in the arm, long remain united in the leg. Farther, the tibial and peroneal nerves are not only sometimes distinct in the pelvis as those of the upper extremity sometimes are in the axilla : but also the cutaneous nerves of the arm are frequently simple branches of the three larger nerves. The difference mentioned above in the crural nerve during its development, also establishes a greater analogy between the two limbs in the early periods of life than at a more advanced age. 2d. The difference in origin depends partly on the preceding fact, partly also on the difference in the direction and situation of the two extremities. If the arm is in the state of pronation, and thus possesses a direction similar to that of the lower extremity, these differences are explained with facility. The antibrachial parts of the median and ulnar nerves are also approximated, and they blend in a single trunk which divides into twobranches at the palm of the hand. SPLANCHNOLOGY. § 1901. Splanchnology, or the branch of anatomy which treats of the apparatus for the functions, includes the description of the most complex parts of the organism, those formed by the union of a greater or less number of simple organs or systems. We cannot consider these as belonging to the class of those already mentioned, as they differ too much from these latter or from each other. We must however remark that they may .finally be referred in respect to their essential characters to the cutaneous and glandular systems. In regard to their functions they may be divided into two classes, one of which establishes an immaterial, the other a material connection between the organism and the external world. The first are the organs of sense, the others are properly termed the viscera. The organs of the se7ises perceive actively the impressions of qualities belonging to the body which they contribute to form, or to external objects. They transmit them to the brain by means of their nerves, and cause in this viscus the formation of ideas , that is, they there produce modifications of the principle of the mind, of which it is the immediate organ. Some of the viscera receive foreign external substances, others remove all that the vital powers have rendered useless, or separate parts proper to form similar new bodies, that is, they remove from the organism all that is useless and which cannot serve to preserve the species. Some of these organs, as the intestinal canal and the lungs, perform both of these functions at the same time ; others, as the kidneys and genital organs, serve only for the excretory function ; they all have this in common, that they form new substances, and that they thus preserve the individual in the normal state. The substance formed by the genital organs serves also and in a special manner to preserve the species. However different the results and the mode of action of the organs of sense and the apparatus of formation may be, the first are in regard to mind exactly the same as are the second in relation to the body. Farther the inferior senses, those of smell, taste, and touch, which are the bases of all, insensibly establish the transition from the superior senses, those of sight and hearing, to the proper viscera, both in respect to their form and situation, and to their mode of action. We may also Vol. III. 15 are provided with simple glands and hairs. 4th. There is only one or at most but two : in the former case they are situated so that the median line divides them into two equal parts j in the second there is only one on each side, a right and a left. As the direct organ of the spiritual principle is that which we considered last, it is most convenient to examine first the organ of the most intellectual sense, that of hearing, and next to treat of that of sight, that of smell, and lastly the organ of taste, which forms a part of the digestive apparatus. After describing this apparatus we shall pass to the organs of respiration and of voice, then to those of the urinary secretion, and lastly to those of generation and the history of the fetus. characters : 1st. They are situated in the head. The organ of hearing is placed the farthest backward and belongs entirely to the skull ; it is also situated the most on the side, and its two lateral portions are entirely distinct from each other. The cavity occupied by the eye is partly formed by the bones of the skull and mostly by those of the face. That of the olfactory organ belongs still more to the face, in fact almost exclusively to it, since the ethmoid bones form less of the skull than of the face. The cavity of the mouth is formed only by the bones of the face. The right and left portions also gradually approach each other from the organ of hearing to that of taste, so that they finally blend in the tongue. 2d. They are all connected by short and large nerves with the encephalon. The auditory is proportionally the shortest and largest nerve. It arises from the calamus scrip torius as from a distinct cavity, so that (1) A. Molinetti, Dissertaliones anatomicœ et pathologicæ de sensibus et eorum organisa Padua, 1669. — Casserio, Pantæsthesejon , hoc est de quinque sensibus liber, organorum fabrieam, usum et actionem conlinens , Venice, 1699. — Haller, De sensibus in gcncre, Gottingen, 1742.— Lecat, Traité des sens, Amsterdam, 1744. — Sœmmerring-, Abbildungen dec menschlichen Sinnorgane, Francfort, 1809. the mass of the encephalon. 3d. Ml receive their nerves from at least two pairs. The larger nerve is termed the nerve of sense , and the smaller the accessory nerve. In the organs of hearing, smell, and taste, the nerve of sense forms as many distinct pairs, the auditory, optic, and olfactory nerves, while in that of taste it is only a branch of the trifacial nerve, which is also the common trunk of the accessory nerves ; but this includes also the hypoglossal, the glosso-pharyngœal and the facial, the three motor and the ganglionnary nerves. The names of several of these nerves prove that the accessory nerves serve principally to excite the motions of the organs of sense. The olfactory nerve is the only one which is to a certain extent an exception to the rule, since its proper accessory nerves, like its nerve of sense, are distributed in the mucous membrane of the nose. The nerves of sense and the accessory nerves are not necessarily connected ; these connections do not exist in the organs of sight and hearing. They are slight and probably inconstant in the organ of smell, and are well developed only in the tongue, which is the most similar to the general organ of touch. 4th. The proper nerves of sense expand more or less evidently as a thin membrane , which is covered directly by a fluid above which is a tissue similar to the epidermis. 5th. They all communicate by ducts more or less broad, the prolongations of the internal cutaneous membrane which make part of them, and which perform a part as much more important in their organization the less they are developed. The more similarity there is between them, as between the organs of taste and smell, the more loose and extensive the communication, so that so they really form but one in the early periods of life, at which time the roof of the palate which will separate the last two from each other is not yet formed. The communication between these two organs of sense and the others is more marked the nearer the fetus is to its period of formation. In fact the cutaneous system is more or less evidently the prototype of all the organs of sense, and the external integuments are the seat of sensation, as the hand is that of the special modification of the general sensation termed the touch. of t lie temporal bone. This organ, the most noble and the most intellectual of the senses, belongs entirely to the skull. It is connected with the encephalon more directly, and is protected better against external injuries than any other of the senses. It is formed of a considerable number of parts differing very much in their form and texture, and which may be divided generally into two sections, comprehending the external and the internal ear. EXTERNAL EAR, § 1904. The external ear, oriente , Ch. (auris externa), (l) is formed by the cartilage of the ear, the cartilaginous portion of the external auditory passage, and several muscles which are attached to the different regions of the auricular cartilage. All these parts are covered by the common integuments. A. CARTILAGE OF THE EAR. § 1905. The cartilage of the ear ( cartilago auris), (2) considered generally, is formed like a short tunnel with a broad oval opening larger from above downward than from before backward. This surface is very uneven from several prominences and depressions which circumscribe this opening. De visione, voce et auditu, Venice, 1688.— J. Mery, Description exacte de l'oreille, l’aria, 1681. — Duverney, Traité de l’organe de l’ouïe, contenant la structure, les usages et les maladies de toutes les parties de L’oreille, Paris, 1683. — C. G. Schelhammer, De auditu liber anus , Leyden, 1684. A. M. Vasalva, Tradatus de aure humanâ, Bologna, 1704. — R. Vieussens, Traité delà structure de l’oreille, Toulouse, 1714. — J. F. Casscbohm, Tradatus quatuor de aure humanâ, Halle, 1734; Tractatus quintus et sextus , Halle, 1735. — Morgagni, Ep. anat., ep. iv., v., vii., xii., xiii. —Geoffroy, Dissertations sur l’organe de l'ouïe de l’homme, des reptiles et des poissons, Amsterdam, 1788. — C. P. C. — Soemmerring, Abbindungen der menschlichen Gehörorgane, Francfort, 1806. — J. S. Schroeter, Das menschliche Ohr, nach den Abbildungen Soemmerrings vergrössert dargestellt, Weimar, 1811. — J. Cunningham. — Saunders, The anatomy of the human ear, illustrated by a series of engravings of the natural size, with a treatise on the diseases ofthat organ, the causes of deafness, and their proper treatment, 1817. — C. S. Pohl, Exposili) generalis anatomica organis auditus per classes animalium, Vienna, 1818. — T. H. Weber, De aure et auditu hominis el animalium, Leipsic, 1830. — J. Van der Hœven, Diss. de organo auditus in homine, Utrecht, 1822. * y others is called the helix. It begins at the centre of the anterior edge of the external ear, goes first from below upward to the upper extremity of the auricular cartilage, then curves backward, and finally descends to the posterior part of the circumference of the ear and terminates imperceptibly at its lower extremity. 2d. A second eminence surrounded by the preceding, and termed the anthelix. It begins below and behind near the lower extremity of the helix, goes upward and forward, separates a little from this latter and divides at its upper and anterior extremity into a superior and an inferior branch, which extend to near the ascending portion of the helix where they gradually terminate. ear. It is termed the tragus. 4th. Opposite the tragus we observe posteriorly a similar prominence termed the antitragus , separated by a groove from the preceding. The helix and the anthelix terminate here. 1st. The scaphoid or navicular fossa ( fossa scaphoidea), a slight depression which is concave forward, convex backward, and which extends between the posterior part of the helix and anthelix. the anthelix. 3d. The concha ( concha auris ), a deep cavity which serves as the entrance to the cartilaginous portion of the auditory passage. It is situated between the helix, the tragus, and the antitragus. The cartilage of the ear extends at its lower part into a semicanal, which is open above and is termed the auditory passage, the auricular or oricular channel ( meatus auditorius cartilaginous). This canal commences at the anterior part of the external ear, where it is more or less covered by the tragus like a valve. Its direction is at first transverse from without inward, or even a little from below upward : it then becomes in most of its course oblique from below upward and from before backward. It is terminated above by the long posterior root of the zygomatic process of the temporal bone, and below this root by some fibrous tissue. The principal space is in part where the direction of the passage is changed in the manner mentioned. There in fact the internal and external portions of its cartilage are not united above and below except by a narrow band. terior wall. The cartilaginous auditory passage is much shorter from before backward, than from above downward. It is about an inch long, four lines high, and three broad. Its inferior part extends inward and downward some lines farther than the upper. It is attached to the adjacent parts of the temporal bone by a firm, short cellular tissue. Its internal orifice particularly unites to the asperities of the external orifice of the bony portion of the auditory passage, of which this cartilaginous portion is the continuation. § 1908. The cartilage of the external ear is entirely covered on its external and its internal face by the skin which intimately adheres to its inequalities. It gradually becomes thinner from without inward, moister and more analogous to a mucous membrane. The entrance of the auditory passage is generally furnished with short thin hairs which are arranged very compactly. The skin which lines it usually presents on its inner face a considerable number of broad rounded openings. These openings lead to a glandular and reddish layer, which surrounds them and secretes the wax {cerumen annum), a thick yellowish, viscous, very inflammable fluid, in which chemical analysis demonstrates a fatty oil, a peculiar albuminous and a coloring substance.^) B. MUSCLES OF THE EXTERNAL EAR. § 1909. The cartilage of the external ear is provided with several muscles(2) which are generally thin and small, and may be referred to two classes ; one includes those which move the whole external ear, and thus contribute to change its situation and direction ; the other is composed of those which move only some of its parts, and modify more or less evidently its general form. § 1911. The attollens auriculae muscle, the superior auricular muscle, temporo oriculaire, Ch., the largest muscle of the ear, is thin and triangular. It arises from the centre of the aponeurotic envelop of the skull and the aponeurosis of the temporalis muscle, contracts from before backward, and is attached to the eminence of the auricular cartilage, which corresponds to the triangular depression between the two branches of the anthelix. § 1912% There are generally three retrahentes auriculæ or posterior auricular muscles, mastoido-oriculaires , Ch. Sometimes there are but two, more rarely four, the inferior of which is very thin. These muscles are always situated successively from above downward, are very small, thin, and elongated. They arise from the mastoid process, and are attached by short tendinous fibres to the centre of the external face of the ear, on the eminence which corresponds to the entrance of the auditory organ. § 1913. The attrahens auriculæ muscle, the anterior auricular muscle, zygomato-oriculaire, Ch., is also very small, but always a little larger than the preceding. It arises on the zygomatic process, goes backward and downward, gradually contracts, and is attached by a short tendon to the inferior and anterior transverse portion of the helix, which forms the commencement of this eminence. II. MUSCLES WHICH MOVE CERTAIN PARTS OF THE EXTERNAL EAR. § 1914. The muscles which move certain parts of the external ear are extremely small and weak, particularly in civilized nations. Being used but slightly or not at all, they cannot modify the form of the external ear, and may be considered as rudiments of those which are much more developed in animals. All are thin, and are attached by all their internal face to the part of the ear which they move. § 1915. The Iragicus muscle, tragien , Ch. is oblong. It arises from the inferior and anterior part of the concha, directly below the tragus, which it covers outwardly. Its superior edge is situated below the lower extremity of this eminence. It rarely goes farther, and extends to the lower extremity of the anterior edge of the helix, in which case it is even blended with the helicis major muscle. § 1916. The anti-tragicus muscle, antilragien, Ch. arises from the upper extremity of the external face of the antitragus, and is attached to the lower extremity of the anthelix. c. Helici3 major muscle. § 1917. The helieis major muscle, grand helicien, Ch.,is elongated. It arises from the inferior extremity of the helix, and ascends on the external and anterior face of this eminence, to which it is attached directly above the point where the ear separates from the head. § 1918. The helicis minor muscle, petit helicien, Ch., is the smallest muscle of the external ear. It is situated like the preceding, on the external face of the helix ; it arises much lower and more posteriorly than it, in the place where this eminence leaves the external ear, and is attached sometimes higher to its ascending portion near the posterior edge. e. Transversus auricula: muscle. § 1919. The transversus auriculae muscle, transverse de l'oricule, Ch., is situated on the internal face of the external ear, viz. that which looks towards the head. It is larger than the preceding, but is formed of fasciculi which are less coherent, and generally also less evidently fleshy. Its direction is transverse in almost all its course, and it extends from the anthelix to the scaphoid fossa. I. OSSEOUS PORTION OP THE AUDITORY PASSAGE. § 1921. The osseous portion of the auditory passage , conduit auriculaire , s. oriculaire , Ch. ( meatus auditorius osseus), when perfectly developed, forms the posterior and external part of the lower face of the petrous process of the temporal bone. It is an elliptical canal, the direction of which is from above downward, from behind forward, and from without inward, which gradually contracts in the same direction. This canal is about half an inch long. Its height exceeds its breadth. Its external orifice which presents grooves and asperities on its edge, is called the external auditory foramen ( porus acusticus externus, aditus admeatum auditorium osseum). It is turned from within outward, and is intimately united to the cartilaginous portion of the auditory passage. Its posterior wall is a little shorter than the anterior. It is lined in its whole extent by a prolongation of the skin which covers ■ the ear, and which gradually becomes thinner from without inward. Its internal orifice presents a considerable depression, a groove in which the membrane of the tympanum is situated. This groove extends all around it, except its upper portion. (1) C, Folius, Nova auris internee delineatio, Venice, 1645. — B. S. Albinus, De aure liumanâ anteriore ; in the Annot. acad., book iv., cap. ii. — A. Comparetti, 06servationes anatomicce de aure interna comparatâ, Padua, 1789. — A. Monro, On the brain, the eye and the ear, Edinburgh, 1797. — Ribes, Mémoire sur quelques parties de V oreille interne; in the Bulletin de la soc. mêd. d’émul., 1823, November, p. 650 December, p. 707. II. MEMBRANE OP THE TYMPANUM. § 1922. The membrane of the tympanum (mem. tympani),(l) which is inclosed in the internal orifice of the auditory passage, separates the canal from that part of the internal ear which is next to it, that is from the cavity of the tympanum. It is a thin, elliptical membrane, the direction of which is a little oblique from above downward, from without inward, and from behind forward. There is positively no opening in it in the normal state, although the contrary opinion has been maintained in several different forms.(2) It consequently completely separates the cavity of the tympanum and the labyrinth from the osseous portion of the auditory passage and from the external ear. As it extends a little farther than the opening which receives it, its form changes in regard to its degree of tension and relaxa tion,(3) which is produced principally by the action of the muscles of the little bones of the ear. It fits exactly into the groove at the internal extremity of the auditory passage. Anatomists differ in opinion in regard to the formation of the membrane of the tympanum. The most correct consider it formed of a special membrane situated in the centre, of a second which is external, situated next to that of the bony portion of the auditory passage. In this view of the subject the external layers would be culs-de-sac of the internal and the external cutaneous system, while the middle layer forms a distinct and special membrane arising from the bony portion of the auditory passage. This special membrane presents very distinct fibres which radiate from its centre to its circumference, and are very manifest in its internal face. Judging from analogy, that is from what occurs in the large animals particularly the elephant, these fibres are probably muscular. (4) The most careful injections demonstrate also numerous bloodvessels which come principally from two circular trunks, an external and an internal, and which anastomose together frequently. (1) A. F. Walther, De membrana tympani, Leipsic, 1725. — Brugnone, Observations anatomiques sur la structure de la membrane du tympan et de celle de la caisse ; in the Mém. de Turin, an. xii., p. 1,(2. — E. Home, in the Phil, trans., 1804. (2) Very recently even Vest, judging from his own observations and those of Wittmann, has maintained the normal existence of an opening' in the membrane of the tympanum, admitted some time since by Rivinus, and long neglected. He asserts that this opening is oblique, and thus forms a kind of valve. But he admits it is frequently deficient ( Uuber die Wittmann ’ sehe Trommclfellklappe ; in the Medicinische Jahrbücher des Oesterrenchischen Staates, vol. v., Vienna, 1819, p. 123-133). To conclude from a few cases, which were probably morbid, that the opening is formed primitively, is evidently to make the exception a rule. F. T. Of the two superficial layers the external is easily insulated : but it is more difficult to separate the internal from the middle, both on account of its fineness and because it adheres to this latter more intimately. X. TYMPANUM. § 1923. The tympanum or the drum ( tympanum , s. cavitas tympani){ 1) is a narrow, rounded cavity, which is generally convex internally and which is continuous outwardly with the osseous portion of the auditory passage by a broad opening before which the membrane of the tympanum is expanded, and forward with the Eustachian tube through another narrower opening. This cavity forms the central part of the internal ear ; hence some anatomists term it the middle ear, in opposition to the labyrinth and all the parts on the outside of it. It occupies the external and posterior part of the petrous portion and communicates anteriorly with the cavity of the mouth, posteriorly with the mastoid cellules. Its internal and very irregular face presents numerous elevations and depressions which are connected with the labyrinth. It incloses the little bones of the ear and the cord of the tympanum. When we consider only the bones, we perceive that it is open forward, backward, and downward. A mucous membrane which is continuous with that of the throat lines its whole extent. § 1924. On the inner face of the cavity of the tympanum, forward and downward, at about its centre is a considerable eminence, termed the promontory ( promontorium ), formed by the commencement of the cochlea, and always covered by osseous substance. At its lower and posterior partis an oblong, triangular opening, more high than broad, which is directed backward and outward ; this is the fenestra rotunda, the cochlear opening of the tympanum.{ 2) This opening communicates with the cochlea, but it is closed by the mucous membrane which lines the whole cavity of the tympanum. (3) Above the promontary and a little above the centre of the tympanum is a second and much larger opening, called the fenestra ovalis, the vestibular opening of the tympanum {fenestra ovalis, s. semi-ovalis). The length of this opening, the greatest diameter of which is directed from above downward and from before backward, exceeds its breadth. special layer, of a second given off by that of the cavity, and of a third coming from that which lines the internal scala of the cochlea. Its structure then resembles that of the membrane of the tympanum. F. T. outward by a small groove. On the posterior wall of the cavity of the tympanum opposite the lower extremity of the fenestra ovalis, farther backward and much more outward, we remark the pyramid (emmentia pyramidalis), a small triangular eminence which terminates forward by an opening which is grooved in it, and which communicates with the Fallopian canal : from the anterior extremity of this a small bridge of bone is frequently detached, which goes to the upper extremity of the promontory, below the fenestra ovalis. receive the upper part of the two largest bones of the ear. Upward and backward it communicates by one or more considerable openings with the cavity of the mastoid process, which must consequently be considered as a prolongation of it. This cavity is divided by numerous septa into cellules, which enlarge much from the centre to the circumference, and which are lined by the mucous membrane which covers the inner face of the tympanum. The internal wall of the tympanum presents at its anterior part a groove which leads into an osseous prolongation ; this extends forward, and is the bony portion of the Eustachian tube ( tuba Eustachii ossea). Above this groove we observe a second, which sometimes is not separated from the other in its whole extent, and which lodges the tensor tympani muscle. Under the posterior extremity of the second groove is a small opening which leads above to the superficial petrous groove, below to a groove which descends on the promontory. This groove becomes at its lower part a canal which opens outward on the lower face of the pyramid, between the carotid canal and the fissure of the jugular vein. Through this canal passes a filament of anastomosis between the second branch of the trifacial, the glosso-pharyngceal, and the ganglionnary nerve ; this minute filament arises from the superficial petrous nerve, enters the cavity of the tympanum with another filament of the great sympathetic nerve, and communicates below this cavity with the ganglion of the glosso-pharyngceal nerve.(l) II. EUSTACHIAN TUBE. § 1925. The Eustach an tube , conduit guttural de V oreille, Ch, ( tuba Eustachii ), is a canal the posterior part of which is formed of bone, but is fibrous and fibro-cartilaginous at its anterior portion, and extends from the tympanum to the upper part of the pharynx. The direction of this canal is oblique from above downward, from without inward, and from behind forward. It is nearly two inches long. canal. It becomes narrow from behind forward. The cartilaginous portion proceeds directly below the base of the skull, but on the contrary gradually enlarges in the same direction. It is compressed from within outward in its wholq extent. Its form is elliptical and it is fibro-cartilaginous in the inner portion and sometimes also in the upper portion of its external wall. In other parts it is composed of a fibrous tissue which arises from the periosteum of the inferior pterygoid process. The Fallopian tube is entirely lined internally by a very fine mucous membrane which is continuous with that of the oral cavity and of the tympanum. Around the buccal orifice of this tube this membrane becomes much thicker, partly from a great development of the muciparous glands. Thence a prominence is formed which changes this opening into a narrow longitudinal fissure and forms a kind of valve. § 1926. The bones of the ear ( ossicida auditus),{ 1) situated at the upper part of the cavity of the tympanum, are the smallest bones in the body. They form a chain composed of pieces movably articulated with each other, which extends from the membrane of the tympanum to the fenestra ovalis, consequently to the labyrinth, and which conveys to the deepest parts of the internal ear the changes which supervene in the membrane of the tympanum. cular bone. (1) J. A. Schmid, De periostoo ossiculorum audilus ejusque vaseculis, Leyden, 1719. — H. F. Teichmeycr, Diss. medica solemnis sistens vindicias quorundam inventorum anatomicorum, Leipsic, 1727.— Magendie, Sur tes organes qui tendent ou relâchent la membrane du tympan et la chaîne des osselets de l'ouïe dans l’homme et dans les animaux mammifères ; in the Jour, de phys. expèrim.., vol. i., p. 341-347, tab. iv. cesses. The head, the upper part, is rounded, oblong, convex and smooth forward, concave and slightly uneven backward. Its posterior face is oblong and surrounded by a slightly prominent edge. A transverse eminence divides it into an upper and a lower face. two processes. The handle ( manubrium ), or the inferior section, descends a little from without inward and from behind forward. It is terminated at its lower extremity by a small prominence, and is situated between the layers of the membrane of the tympanum. The external or the short process {processus externus , s. obtusus , s. brevis) projects more or less at the upper extremity of the handle, and forms with it. a right angle. It is directed outward, and is separated by a deep groove from the head, into which the upper side of the internal extremity, of the auditory passage enters. The anterior long or spinous process ( processus anterior, s. longus, s. spinosus ) is thinner but much longer than the preceding, and is convex above and concave below. It is received by a broad and superficial groove hollowed on the inner face of the upper extremity of the ring of the tympanum. termed the body. , The body is almost square, flat, and presents forward a concave surface by which the bone articulates with the head of the malleus (§ 1926). It is situated above the membrane of the tympanum. The upper or posterior and shorter branch is flattened from within outward, terminated by a blunt summit also situated above the membrane of the tympanum, and is directed horizontally from before backward where its loose extremity terminates. . The anterior or inferior branch varies in length and is almost straight ; its direction is from above downward and from behind forward, and it is situated more internally than the preceding. It terminates in a small button-like prominence ; it is situated behind the handle of the malleus, a little on the outside of it. The body of the incus articulates above and forward with the head of the malleus, by its long branch below with the stapes. It is not directly connected with the membrane of the tympanum. § 1929. The lenticular bone - (os lenticulare , s. Sylvii) is an extremely small, flat, and rounded bone, situated on the inner face of the lower extremity of the long branch of the incus. It generally fuses with the incus very early, even during the latter months of pregnancy, and then forms an eminence which projects on its inner face. d. Stapes. § 1930. The stirrup ( stapes ) is situated more internally than the other two bones of the ear, and is not perpendicular like them but horizontal. It is composed of a head, two branches , and the transverse face or the base. The head is rounded, oblong, and flattened from above downward. Its upper extremity looks outward and presents a slight depression for the lenticular bone : the two branches are sometimes separated by a contracted neck. The anterior branch is always shorter and also straighter than the posterior branch. Both are grooved on their internal faces, which look towards a groove in which a membrane, ! a prolongation of that of the tympanum, extends between them. The base has exactly the same form as the fenestra ovalis, with which it is movably united by the membrane of the tympanum. It is always a little narrower, so that it can enter and leave the vestibule through this opening. § 1931. The small bones of the ear are moved by four muscles, which, like the bones to which they are attached, are the smallest in the body. Three of these are inserted in the malleus and one in the stapes. Two muscles. of the malleus are situated before the cavity of the tympanum, the third above this cavity. That of the stapes is situated behind it. The incus has no special muscle : it forms only a connecting link between the malleus and the stapes. § 1932. The three muscles of the malleus from their connections of the bone with the membrane of the tympanum vary the degree of tension of this membrane. They are distinguished into an internal and an external. 1. Tensor tympani muscle. § 1933. The tensor tympani muscle, the internal muscle of the malleus {m. tensor tympani , s. mallei interims) is elongated. It arises from the upper part of the cartilaginous portion of the Eustachian tube near the sphenoid bone, and generally comes from its large wing. Its direction is from before backward in the canal from which the petrous process is grooved to allow it to pass to the osseous portion of the tube. In the cavity of the tympanum the direction of its tendon changes, leaves the internal wall of this cavity, goes outward and is attached to the upper extremity of the inner face of the malleus directly below its long process. This muscle draws the malleus inward, tenses the membrane of the tympanum which the bone draws with it, and brings the chain of bones inward so as to -sink the stapes into the fenestra ovalis. § 1934. The laxator tympani major muscle, the great external muscle of the malleus (JVf. laxator tympani major , s. mallei externus major), arises from the grooved prolongation of the great wing of the sphenoid bone, and is directed from without inward and from before backward. Its tendon enters the fissure of Glaser and is attached to the long process of the malleus. § 1935. The laxator tympani minor muscle, the small external muscle of the malleus {JVL. laxator tympani minor , s. mallei externus minor) , is much smaller than the two preceding and arises from the upper edge of the osseous portion of the auditory passage, passes between the layers of the membrane of the tympanum, goes forward and outward, and is attached sometimes higher and sometimes lower to the handle and the external process of the malleus. b. Stapedius muscle. § 1936. The stapedius muscie (M. stapedius) is oblong and triangular. It arises at the base of the pyramid and goes forward and upward. Its tendon comes through the anterior opening in the top of the pyramid, and is attached to the posterior part of the head of the stapes. It draws the stapes backward so as to bring the posterior portion of its base into the fenestra ovalis. It also draws the chain of the bones inward, and thus tenses the membrane of the tympanum. C. INTERNAL PORTION OR LABYRINTH. § 1937. The labyrinth (labyrinthus),{ 1) the most internal part of the organ of hearing, comes next inside to the tympanum. It is a double cavity situated in the petrous portion of the temporal bone, directly surrounded by the very firm substance of this portion, and is formed of several compartments of very complex figures. We distinguish in it a central part the vestibule , a posterior part the semicircular canals , an anterior portion the cochlea s and the lateral parts the aqueducts. I. OF THE OSSEOUS LABYRINTH. § 1938. The osseous labyrinth in the adult is not distinct from the compact substance of the petrous process of the temporal bone, of which it forms the most internal, the firmest and the hardest part, which closely envelops and covers the membranous labyrinth. But in the early periods of life it is formed by a solid, hard, and brittle substance, separated from the external layer of the petrous process by a less compact osseous tissue. Its internal face is moistened with limpid serum which exactly fills all the space between it and the membranous labyrinth. (2) During the early periods of life we find between the two labyrinths a membrane which is not the periosteum of the osseous portion, although generally considered as such, but which belongs to the class (1) A. Scarpa, Disquis. anatomicæ de auditu et olfactu, Pavia, 1789. — A. Monro, lee. cit. — Brugrone, Observations anatomico-physiologiques sur le labyrinthe de l’oreille ; in the Mémoires de Turin , 1805-1808, p. 167-177. of sero-mucous membranes. This is demonstrated by the numerous vessels it receives and by its abundant secretion and its connections with the membrane of the tympanum. a. Vestibule. § 1939. The vestibule ( vestibulum),(\ ) the middle of the bony labyrinth, is situated farther inward and more posteriorly than the tympanum. It is of a rounded and oblong cavity at about the centre of which we perceive the internal orifice of the fenestra ovalis. We there remark principally two small depressions or superficial grooves, one superior , posterior and external , more extensive than the other and of an oval form (fovea, s. cavitas ovalis, s. elliptica, s. semi- elliptic a) ; the other inferior and anterior, smaller and semicircular ( fovea hemisphœrica, s. orbicularis). The first is situated on the posterior and inferior wall, the second on the superior and external. They are separated by a sharp crest which extends from above downward. and one which is rounded and very small. Of these six large foramina, one which occupies the anterior and inferior part of the vestibule leads to the superior scala of the cochlea ; the other five situated at the posterior part are the orifices of the posterior part of the labyrinth or the semicircular canals. posterior and largest part of the labyrinth. There are three of them which occupy a square space : the superior or anterior, the posterior , internal or inferior, and the external. The first two are perpendicular, the third is horizontal. When united they form more than half a semicircle. They are much more prominent at one of their extremities than at the other and in the rest of their course, so that they represent in this place a rounded vesicle (ampulla). They are not perfectly round externally nor intefnally, but are slightly flattened and elliptical. Their orifices are a little broader than the rest of their course. The superior is oblique from without inward and from before backward. It forms the highest part of the labyrinth, and its two branches are separated the farthest. Its anterior and external opening, which is situated above the fenestra ovalis, forms a considerable vesicle of which we see another trace at its posterior extremity, through which it blends with the superior opening of the internal canal. The inferior is also perpendicular, but its convexity looks backward and its concavity forward. It commences above by a short canal which it has in common with the internal extremity of the superior, and terminates by a vesicular enlargement below and inward in the vestibule. It is the longest and its branches are nearest each other. The external or horizontal arises by a slightly marked vesicular prominence below the external orifice of the superior. Its internal orifice in the vestibule is situated on the outside and below the common opening of the superior and the inferior. c. Cochlea. § 1942. The cochlea(l) forms the anterior and most complex part of the labyrinth. It presents to a certain extent the repetition of the semicircular canals, and its figure perfectly resembles that of the shellfish whose name it bears. It is a grooved canal which gradually diminishes from its origin to its extremity, and thus it finally becomes very narrow. It turns around a central and perpendicular portion termed the axis (modiolus), which gradually becomes thinner. It thus describes two turns and a half. others however project much beyond it. § 1943. A horizontal plate of bone, which arises from the inner part of the cochlea and which is termed the spiral septum ( lamina spiralis ), divides it into two canals situated one above the other and termed the scalæ. (1) G. Brendel, De auditu in apice cochleae, Program. I. II, Gottingen, 1747. — J. G. Zinn, Observationes de vasis subtilioribus oculi et cochlea auris internee, Gottingen, 1753. — J. G. llg, Einige anatomische Bemerkungen, enthaltend eine Berichtigung der zeitigen Lehre vom Bau der Schnecke des menschlichen Gehörorgans, nebst einer anatomischen Beschreibung und Abbildung eines durch ausserordentliche knochenwucherung sehr merkwürdigen menschlichen Schädels, Prague, The inferior lamina is much broader than the superior, and terminates backward and outward in the fenestra rotunda in the tympanum. This has been termed the scala of the tympanum ( scala tympani). It is separated from the cavity of the tympanum by a membrane which presents a depression on the side of this cavity which is termed the secondary tympanum ( tympanum secundarium) . The superior scala is much narrower than the inferior. It terminates at the anterior opening of the vestibule. Thence it is termed the scala of the veslibide ( scala vestibuli). The cochlea however does not continue separated the entire length of this cavity, and the spiral septum terminates near the middle of the second turn in a pointed hook termed the hook of the cochlea ( hamulus cochleae). By uniting in this manner, the two canals of the cochlea give rise to a tunnel-like cavity, the infundibulum ( scyplms ), the base of which is turned upward and the summit downward towards the cupola of the cochlea. This conical cavity forms the most prominent part of the cochlea. The axis(l) which turns on itself is hollow like the scalæ. A larger canal passes longitudinally through it from its base to its summit. It also presents numerous small openings, the diameter of which gradually diminishes from its base to its summit. These openings lead to s>nal} canals which terminate on the spinal lamina. (2) (2) Anatomists have hitherto considered the axis of the cochlea as a small column formed by a very thin osseous lamina, through which a canal passes from the base to the summit, which is perforated by numerous small foramina. It is asserted that it terminates at the second turn of the cochlea, at the top of which it appears on leaving this place as a tunnel-form layer of bone, the summit of which is the termination of the axis, and the upper extremity of which looks towards the summit of the cochlea and is covered by a plate of bone. Hence are distinguished the cavity of the axis and that of the infundibulum. There is also admitted in the latter a thin column around which the spiral septum turns from the second curve, and which terminates in a small osseous plate curved like a hook. Ilg describes the structure of this axis differently. He states that the spiral channels of the cochlea do not turn around a special nucleus of hone; hence he does not admit an axis, but asserts that it is the inner and concave wall of the spiral canal which forms the species of column around which this canal turns, and that we perceive in it the form of a cylinder on ppening the first and second turn of the cochlea. The column is very thick in the first turn where it is a line and a half in diameter, but very thin in the'second where its diameter does not exceed half a line. As the internal wall of the spiral canal forms what is termed the a?is in the first two curves, so likewise if produces something similar in the third. But. this pillar of the third turn has not the form of a cylinder ; it is composed only of a very thin and twisted osseous plate, which arises from the summit of the cylindrical column and extends to the cupola of the cochlea, ■where it is attached. The loose edge of this plate, which exists all the length of the imaginary axis of the cochlea, from the termination of the cylindrical column to the top of this cavity, is smooth, rounded, and generally a little concave in the direction of its length. Sometimes also it represents a small column which goes directly to the summit of the cochlea. The axis of the column is perforated by a small canal, and this column is filled to the second turn by an osseous cellular mass, the cellules of which communicate with numerous small foramina grooved along the parietes of the column, and into which open some small canals which proceed between the two Jayerg of the septum or spiral lamina. Rosenthal has since modified and rectified the d. Aqueducts. § 1944. The aqueducts ( aquceductus , diverticula, )(1) of the labyrinth are short, narrow canals, which are directed from above downward through the substance of the petrous process of the temporal bone, and which enlarge a little in their course. There are two, the aqueduct of the vestibule , and the aqueduct of the cochlea. The aqueduct of the vestibule ( aquceductus vestibuli) begins by a very small opening in the inner wall of the vestibule before the common opening of the two perpendicular semicircular canals in the sulciform groove of the vestibule, which is in fact their internal orifice. It first goes a short distance from without inward and a little from below upward in the centre of the petrous process, then from above downward, insensibly enlarges on leaving this curve, and after proceeding about four lines terminates a little behind the centre of the inner face of the petrous process of the temporal bone near the fossa intended for the gulf of the internal jugular vein, with which it always communicates by a slight groove. The aqueduct of the cochlea ( aquceductus cochlea ) commences by a wider opening in the tympanitic scala of the cochlea directly before the fenestra rotunda, descends from before backward, enlarges in this course, and terminates by a triangular opening at about the centre of the inferior edge of the petrous process of the temporal bone. description of Ilg. It follows from his researches, that from the summit of the pillar of the first two turns a layçr proceeds in a semicircle to the external wall, and terminates by a loose and semilunar edge, which ascends to the infundibulum. The last turn is open on the side of this edge, by which the lamina turned opposite the pillar terminates, and the unciform extremity of the spiral lamina which is reflected around tire same edge projects in the turn in question ; the two laminpe terminate in this place, or rather blend in this small rounded cavity. The crook turning around the edge of the lamina of the axis in the place where this lamina separates from the centre of the pillar, is like the extremity of the latter, separated from the infundibulum. The edges of the spiral lamina and of that of the pillar are fitted to each other, cross so that their faces are turned from the side of the external wall of the cochlea, and as the latter inclines a little towards the centre of the pillar, they form in some measure a broad tunnel-like edge for the canal grooved in the first two turns of tfie column to emerge. It follows then from Rosent hal’s description: 1st, that, as Scarpa and some other anatomists have asserted, the base of the infundibulum is situated on the summit of the cochlea and its summit in that of the pillar, but it does not extend so deeply as they assert, for it terminates below the last semiturn and is loose below the cupola of the cochlea, and there is no extended lamina of the column which unites with its covering ; 2d, that Ilg is mistaken in saying that the axis extends to the centre of the cochlea, to its roof, and that it does not form a tunnel-like edge, and is attached to the summit of the cochlea by a rounded point closed at its extremity, P. T. They also serve for the passage of the arteries which enter the labyrinth and the veins which come from it and the lymphatics, the absorbent action of which prevents the abnormal accumulation of serum in this cavity. The veins, and perhaps some of the lymphatics also, empty into the internal jugular vein. This explains why mercury and other fluids pass from the labyrinth into this vein through the aqueducts, after distending the sacs of the membranous labyrinth. ear is always exactly filled with scrum, had been obliged to explain how this liquid can be moved by the compression exercised upon it by the base of the stapes to suppose the existence of derivative canals, which allow it to escape in part, and to leave a certain space between it and the parietes of the ventricle. The observations of Brugnone and of Ribes, which we shall mention hereafter, overturn all this theory. These anatomists consider the pretended aqueducts only as passages for the arteries and veins. In regard to that of the vestibule, Ribes has discovered that at about the centre of the posterior face of the petrous portion of the temporal bone, where it begins as an uneven and undulating layer, it goes forward, upward, and outward, proceeds first on the inside of the posterior semicircular canal, next between the posterior wall of the vestibule and the superior semicircular canal, curves and penetrates into the concavity formed by this canal, thence goes backward and outward, and is distributed in the spungy tissue of the posterior part of the labyrinth. This duct is at first very broad, and it contracts much in its course upward. It generally gives off in its course other smaller duets, at each of which it becomes smaller, and among which Ribes has found some which opened into the inner part of the vestibule, others into the posterior semicircular canal, but only in three pieces, for in all others there was no duct from the aqueduct proceeding either within the vestibule or to any other point within the labyrinth. Besides this aqueduct does not exist in the full grown fetus nor even some time after birth. It is designed to contain the blood-vessels which ramify in all the spongy tissue surrounding the labyrinth, and sometimes enter into the vestibule. Ribes asserts that the aqueduct of the cochlea arises at the base of a small depression situated about the centre of the lower edge of the petrous portion of the temporal bone, ascends obliquely to the lower part of the internal auditory passage, passes under the labyrinth, goes horizontally backward and outward, and terminates not in the internal scala of the cochlea, as is stated, but in the canal of the fenestra rotunda below the membrane which closes its opening. As this passage proceeds towards the tympanum it gives rise to numerous branches. It lodges the vessels which are distributed under the labyrinth in the spungy tissue of tne petrous portion of the temporal bone and within the tympanum. Thus the two pretended aqueducts belong to the class of vascular canals described in a note on the osseous system. But there are others beside them observed in the petrous process. Ribes mentions three others-: 1st, one which arises at about the centre of the posterior base of the petrous process near its upper edge and two lines from the internal auditory passage, goes backward and outward, passes under the anterior semicircular canal, opens directly under the curve of the superior semicircular canal, where it receives the pretended aqueduct of the vestibule, with which it then goes into the spungy substance of the posterior part of the petrous process and in the mastoid cellules, lined by a prolongation of the duramater : 2d, another which arises near the centre of the anterior face near the upper edge of the petrous portion, and goes behind the superior semicircular canal: 3d, another which arises at the bottom of the longitudinal fissure which indicates the union of the petrous process with the squamous portion of the temporal bone, and through which pass some vessels which are distributed in the mastoid cells and the membrane of the tympanum. These details may seem minute, but they are of the highest importance, since they contribute to destroy an anatomical error on which rests a part of the theory by which physiologists still explain the philosophy of hearing. F- T. smaller. It is formed of a thin and whitish membrane, differing entirely from that which covers the inner face of the osseous labyrinth in the early periods of fetal existence. Its external face adheres to the inner face of the bony labyrinth by a loose cellular tissue. It contains in its cavity a fluid called the serum of the membranous labyrinth or the lymph of Cotugno , ( aquula labyrinthi membranacei) .(2) Numerous vessels are distributed in its external face. The upper and posterior part of the osseous vestibule is occupied by a rounded and oblong membranous sac in which the membranous semicircular canals open, which enlarge also in the parts which correspond to the enlargements of the osseous canals. Before this sac we find one which is rounded, perfectly closed, and consequently entirely separate from the membranous labyrinth, which is smaller, situated partly in the semicircular fossa, and also filled with a serous fluid. These two sacs are attached to the osseous labyiinth by their posterior wall. The anterior, which looks toward the anterior wall of this latter and the fenestra ovalis, is loose and surrounded by the serum of the osseous labyrinth. The semicircular canals are arranged precisely like the osseous semicircular canals. The membranous cochlea is formed by a fibro-cartilaginous layer, the membranous spiral lamina, which is adapted to the external and loose edge of the osseous spiral lamina, and which becoming softer and thinner on the outside is attached by its external edge to the outer side of the osseous cochlea. This lamina is longer than the osseous, for it extends to the summit of the cochlea.. In this part of its course it is loose on its inner edge, while the external is attached as in every otljer part. It terminates in a prominence. mor fills the labyrinth, but there are many in whom it is partially empty, and who nevertheless always hear perfectly. He concludes, from these remarks, that the labyrinth is not constantly filled by serum, and that then there is in fact a space doubtless occupied by an äeriform fluid ; but this space, he adds, does not always exist equally in all the cavities of the labyrinth. Sometimes, in fact, we find little of this humor in the semicircular canals, and much in the vestibule and the cochlea ; and sometimes the semicircular canals are full, while the other cavities contain but little. Finally he thinks that these changes depend only on the situation in which the cadaver is held. These observations fully confirm those of Brugnone ( Mém . de Turin, vol. xvi., p. 167), who also thinks that there is almost always serum in all the cavities of the labyrinth, but that this liquid does not exactly fill them in the natural state, because spaces exist in ice removed from them, although liquids acquire more volume by congelation. F. T. III. AVDITOBY NEBVE. § 1946. We have already mentioned the origin of the auditory nerve and its course to the internal auditory passage, accompanied by the facial nerve. On entering this canal the auditory nerve divides into several branches, -which enter the labyrinth, and the progress of which is indicated by the arrangement of the bones. In fact the internal auditory passage(l) presents at the base of its cavity forward, in the place where the internal and perforated plate of the axis of the cochlea is situated, a crest, the direction of which is from before backward ; it is at first slightly sensible, but is very marked in the adult, which divides it into two halves, a superior and an inferior, which is larger. The first belongs entirely to the facial nerve, while the other belongs to it only in a small portion of its anterior part, so that we may say that the superior groove receives the facial nerve, and the inferior the auditory nerve. The first is divided by a longitudinal prominence into two halves, an anterior, the commencement of the Fallopian canal, and a posterior, in which the superior branch of the auditory nerve is situated. § 1947. The auditory nerve is distributed to the membranous labyrinth.(2) Its first branches go to the semicircular canals and the ves-^ tibule. The first, the largest, passes through the depression behind the origin of the Fallopian canal, and arrives at the sac of the superior semicircular canal ; the second goes to the oval depression of the vestibule ; the third, still smaller, arrives at the sac of the posterior semicircular canal. When the first branch has arrived thus far it divides into two twigs, which separate like a fan ; one of them goes to the larger or common sac of the semicircular canals, while the other belongs to those of the superior and the external canal. All these twigs are evidently fibrous and interlace on the outer face of the sacs, but when examined on their inner face they appear to be a formless mucus. They do not extend over the whole vestibule and the semicircular canals, but remain very distinct upon the surface of the sacs. The nerve then goes forward in the axis of the cochlea, follows exactly the curves of the cavity, and gives off numerous filaments which go inward through the openings in its axis. The most internal of these filaments pass through the openings in the curves of the pillar, enter into the canals which terminate there, arrive on the spiral lamina, form an extremely minute plexus along its two faces, and terminate on the membranous spiral lamina, where they are entirely exposed. Scarpa(l) asserts that they proceed only between the two plates of the spiral lamina ; but they in fact cover also the outside of the superior and inferior faces of this Jayer,(2) and those seen in this place, particularly those on the lower face, are even the largest. Some fewer and much smaller filaments pass through the foramina in the spires of the cochlea near the pillar, and go not into the spiral lamina, but to that portion of the membranous cochlea which forms its external wall. All anastomose together on the outside of the cochlea. The nervous filaments which enter the cochlea are, like the preceding, white, opaque, and evidently fibrous near their origin ; but their latter expansions are semitransparent, more gray, and similar to mucus. § 1948. The changes which are communicated to the cerebrum by the auditory nerve and excite there the sensation of sounds, take place in the expansions of this nerve in the membranous labyrinth. These changes are doubtless caused by the compression which the serum in the labyrinth exercises on the ramifications of the nerves, and this pressure is necessarily the consequence of a change in the state of the parts on the outside of the labyrinth, especially in the little bones of the ear and their muscles. In fact, according as the base of the stapes is more or less deeply, and partially or wholly imbedded in the fenestra ovalis, it compresses the serum within it in different degrees, and presses upon different parts of the labyrinth. The external ear and the membrane of the tympanum principally serve to receive the undulations of sound and to strengthen them, which is effected by the tympanum and the mastoid cells. In regard to the little bones of the ear, independent of the use assigned them, the malleus certainly modifies the degree of tension of the membrane of the tympanum, serving to diminish it in loud and to increase it in weak sounds. The Eustachian tubes serve to evacuate the fluids secreted In the tympanum and to admit the air, to balance that acting on the outside of the membrane of the tympanum. They concur also directly to healing, for they also lead into the tympanum the undulations of sound, which, reflected by the w'alls of this cavity, fall principally on the membrane of the fenestra rotunda, called for this reason the accessory tympanum. (3) (3) Savart has concluded from his important researches on the mechanism of hearing : 1st, that the communication of the vibrations by tire air seems to take place, at least for small distances, according to the same laws as those for solid bodies; 2d, that it is not necessary lo suppose a special mechanism to cause the membrane of the tympanum to vibrate continually in unison with the bodies which act § 1949. The external part of the organ of hearing does not begin to appear till towards the end of the second month of pregnancy. It first resembles a slightly perceptible eminence formed like an elongated triangle, the base of which looks upward, the summit downward, and which is directly continuous with the lower part of the side of the head, and in the middle of which is a triangular longitudinal fissure which becomes narrower and deeper from above downward. The prominence which surrounds the median depression soon rises to its posterior part, and becomes thinner in this place. It projects above the surface of the side of the head, and slightly shows the median fossa. At the same time, or soon after, the anterior part of the prominence is divided by a transverse fissure which arises from its posterior part into two halves, of which the inferior is the antitragus and the superior the commencement of the helix. At the same time this anterior part of the external ear also rises and the posterior enlarges, but is not re- upon it, and that it is always in the conditions fit to be influenced by any number of vibrations ; 3d, that its tension probably does not vary, except to increase or diminish the extent of these variations, as Bichat had asserted, but always supposing', as Meckel still admits, the contrary of what residts from these experiments, that is, by imagining that the membrane is loose in loud and tense in feeble sounds ; 4tli, that the vibrations of the membrane extend to the labyrinth unchanged by means of the little bones ; 5th, that the little bones also serve to modify the extent of the vibrations of the parts in the labyrinth ; Cth, finally that the tympanum probably serves to contain an air the physical properties of which are constant. Itard asserts that the membrane of the tympanum does not perform any motion which is visible or denoted by a bristle situated in the centre ; but the more delicate experiments of Savart do not allow us to doubt these motions. When we saw the temporal bone on the level of the external face of the membrane, and cover this with sand, we can perceive that the grains move slightly when we bring a disque which is vibrating, parallel to the membrane and near the surface, although its slight extent and especially its form do not allow us to establish there any nodal line. Itard states that the function of the little bones, are to allow us to hear low tones. J. F. St. Hilaire thinks that they arc of but little use, and are only indications of the respiratory apparatus, the operculum, developed in fishes. The justice of this second proposition, which we shall not examine here, would not necessarily involve that of the first, although not contradicted by experience. The direct participation of the Eustachian tube in hearing, which was asserted in the commencement of the last century, and afterwards brought forward by Brcssa, is evidently erroneous. It has been perfectly refuted by Cotugno and Itard. If it was correct, we ought, as Rudolphi asserts, hear our own voice when speaking loudly after stopping the ears : hut this is not true. Itard has very ingeniously compared the Eustachian tube to a hole without which the air in a military drum would not vibrate ; but he is mistaken in saying that it seems only to renew the air in the tympanum. This is undoubtedly its principal function, but it also serves to excrete the1 mucus and the condensed perspirat ion constantly secreted by the mucous membrane of this cavity. F. T, moved farther from the side of the head. The anthelix and the tragus are developed also very early at the third month. The anthelix is at first more prominent than it is subsequently, because the posterior edge of the ear rises but slightly or not at all. The lobule appears last. younger the fetus is. Its cartilage begins to appear at the third month ; but it is developed slowly, for towards the end of pregnancy it is not as yet so extensive under the skin as in full grown individuals. ear, is at first proportionally much smaller than subsequently. The long portion of this passage begins to form some time after birth by the enlargement of the cavity of the tympanum. Its ossification is singular in this respect, that it generally begins much sooner in the external part of the canal, where it unites to the cartilaginous portion, than in the middle region of its lower part. The prolongation of the external cutaneous system, around which this passage is situated, already exists very early in the fetus, and it is' not then even proportionally much shorter than in the adult, but it has another form and another direction. As the direction of the tympanum is then much more oblique from without inward than it is afterward, the upper part of its circumference at first does not exist ; the inferior alone is developed, and forms on the outside and at the bottom of the tympanum, a large sac, which is much more ample in proportion to its length than it is afterward, descends also more perpendicularly, and is situated below the membrane of the tympanum, so as really to form its upper wall. thicker in the fetus than in the adult. § 1950. 1st. The tympanum in the early periods of life is proportionally shorter and narrower than at a later season, particularly, because the mastoid process is very small, and its cells are not yet formed. It is filled in the fetus with a thick gelatinous fluid, and it communicates with the mouth more directly the younger the fetus is, since the Eustachian tube is shorter and broader in the same proportion. The cartilaginous portion of this tube, until the middle of pregnancy, is simply membranous, and even in the full grown fetus the bony portion is at most separated within the canal by a layer of bone, which formation continues most generally through life, so that the septum rarely extends also to the outer side. The tympanum, and with it the membrane, are much larger in proportion either to the external ear or to the whole head and body, the younger the fetus is, and even until the fifth month of pregnancy, both arc larger than the external ear. Besides, as the osseous portion of the auditory passage is not yet developed, the membrane of the tympanum is much nearer the surface in the early periods of existence than subsequently, so that the upper part directly touches the entrance of the cartilaginous portion of the auditory passage, and consequently is almost exposed in this point, a very curious circumstance from its analogy with reptiles. Both also differ at first in direction, which is more horizontal, because at this period the membrane of the tympanum is more oblique from above downward and from without inward. by their uncommonly early appearance and development. They are visible and even uncommonly large in proportion, at the commencement of the third month of pregnancy, although at this period they are still entirely cartilaginous, and we cannot well distinguish the stapes from the incus. Thus, for instance, the malleus is about three lines high in the fetus of four months, so that the body being then four inches from the vertex to the coccyx, its length is to that of the whole body as 1 : 16, while in the adult, where is to four lines long, and where the distance between the vertex and the coccyx is two feet and a half, the proportion is only as 1 : 90. The small bones of the ear are as large in the full grown fetus as in the adult. They begin to ossify also very early, even before the end of the third month. Cassebohm asserts(l) that the stapes and incus ossify sooner than the malleus, that the osseous nucleus of the incus is seen first in its anterior branch, and that of the stapes in the head, whence it extends along the two branches to the base, which, with the lower region of the anterior branch, ossifies the last. In the malleus, ossification commences in the head and anterior process. Our observations do not exactly agree with those of Cassebohm. It is true that the anterior branch of the incus ossifies before the posterior : we have always found it perfectly ossified, while the latter was entirely cartilaginous, but the ossification of the malleus commences at the same time as that of the incus, and the stapes is still entirely cartilaginous, when it has advanced considerably in the other two bones. The place where it begins in the stapes is not well determined : it is sometimes in the lower part of the posterior branch, and sometimes in the base, but never, according to our observations, in the head. These bones differ very much in their forms. The incus changes the least. The branches of the stapes seem at first not to be separated from each other, which deserves to be noticed on account of the analogy resulting from it with the formation of this bone in the cetaceous animals, and with that of the inner part of the single bone of the ear in birds and reptiles. It is certain that even where these two branches are detached from each other, the opening between them and the base is proportionally much smaller than at subsequent periods, although, however, its form is then less oblong. This narrowness of the foramen, which is evidently an approximation to its entire deficiency, and the union of all the parts of the stapes in one, depend principally on the greater thickness of its branches. this respect. The most remarkable difference is the existence of a right cartilaginous process, formed like a very elongated cone, which is also very long and very thick in proportion to the rest of the bone. This process arises from the anterior side of its head, leaves the tympanum between the petrous process of the temporal bone and the ring of the tympanum, is fitted directly to the inner face of the lower jaw, and extends to the anterior extremity of this bone, where it sometimes, perhaps even always, unites with that of the opposite side. This cartilage never ossifies, although in the commencement it forms most of the mass of the bone ; it disappears at the eighth month. The anterior process of the malleus corresponds with it, it is true, to a certain extent, in respect to its position : but we also perceive that in the fetus, where the two parts are distinct from each other, the cartilage is situated above the anterior process. We may then at most admit that this latter makes part of it, and that they are separated very early. This cartilage is very curious, because fishes, reptiles, and birds, present a similar one, which extends from the posterior to the anterior portion of the lower jaw. In these animals it rests on a small bone placed on the inner face of the posterior part of the lower maxillary bone, and we may consider it as a rudiment of the malleus, which does not exist in them. 3d. The membranous labyrinth exists long before the osseous labyrinth. We have found it at three months perfectly developed in the cartilaginous mass, which afterwards ossifies. Even in the early periods of life it is more distinct, and formed of firmer and more solid membranes than at subsequent periods. It is composed at first of two very distinct membranes, an external and an internal, which are simply inclosed in each other, but there is no continuity between them. The internal is white, transparent, thinner, but firmer and more elastic than the external. The latter does not adhere to the cartilage, as afterward it is not attached to the bone which is developed at the expense of this latter. The inner face of the external membrane is smooth, and the external is corrugated. It gradually disappears, so that at seven months we cannot trace it. Before entirely disappearing it gradually becomes thinner. The internal becomes proportionally narrower but firmer : it seems to be attached more intimately to the inner face of the cartilage which surrounds it, in the early periods of existence than subsequently. As yet we have been unable to ascertain if there is not a period when the membranous labyrinth is uncovered in the skull, at least in part, and where its structure is more simple than it is afterward. At three months it is entirely surrounded by a mass of cartilage, and is as complex in its structure as at a more advanced period of life. We only remark, that like the cartilage which envelops it, it is at first more compressed from without inward, and proportionally higher, which undoubtedly depends, at least in part, on the greater development of the encephalon. At four months we find the membranous cochlea as complex as it is in the adult, while afterward its circumference seems to be formed only by the membranous labyrinth; it is then constituted by a very thick membrane, which makes a part of this latter. We have as yet been unable to obtain any sufficient data in regard to its form before the fourth month of pregnancy. The secondary tympanum and the finestra rotunda are at first situated more externally and parallel to the membrane of the tympanum. They afterwards go backward, which depends principally on the development of bone in their circumference. 4th. When we study the development of the osseous labyrinth, we must distinguish the formation of the osseous substance of the petrous process of the temporal bone from that of its own. The first commences before the second, and follows the usual mode of ossification, that is, it takes place by the development of a loose, soft, and plexiform tissue, in the homogeneous mass of cartilage previously existing, which gradually extends from before backward. The circumference of the fenestra rotunda ossifies first towards the end of the third month, which is curious as an analogy between this opening and the tympanum. Ossification begins at the upper part, then extends to the lower, and when it has thus formed a ring, it goes forward. At the same time there is developed a special osseous nucleus, which is entirely distinct from the preceding, at the outer extremity of the superior perpendicular semicanal : next there appears a third small scale at about the centre of the internal perpendicular semicanal. At the same time ossification proceeds rapidly backward and downward from the point first formed, and gives rise to the floor of the labyrinth. The second nucleus enlarges more quickly perhaps than the first, so that the superior perpendicular semicanal is soon entirely ossified, excepting only its lower and concave face. At the same time, ossification, commencing at its internal extremity, advances on the internal face of the petrous' process, circumscribes the internal auditory foramen, enters within it, and forms the floor of the cochlea. The horizontal semicircular canal begins to ossify at the fifth month. At this time the piece of bone which forms the superior perpendicular canal extends backward, downward, and outward, around the membranous horizontal canal. At least we have been unable to discover a special nucleus for this canal, which seems to ossify by the extension of the first two nuclei, the edges of which finally unite. The formation of the interior of the cochlea belongs almost wholly to the osseous labyrinth. The cartilage and then the osseous substance of the petrous process, do not participate in it except by a narrow prolongation sent by this latter into the cavity containing the membranous and then the osseous labyrinth, the spires of winch it slightly separates. The loose edge of this projecting lamina is turned outward. It extends from the upper part of the fenestra rotunda and the outside of the cochlea, to the summit of this latter, across its cavities, and thus divides it anteriorly, but very imperfectly, into an external and an internal cavity. This lamina is broader at first than it is subsequently. Besides, the internal face of the cochlea is entirely smooth, and this part of the internal ear presents at this period the greatest analogy with the cochlea of birds : at a later period, after the third month, as the cochlea enlarges from without inward, the lamina in question becomes narrower, and at the same time slight prominences are developed, which separate externally the two and half turn's of the cochlea from each other, and make part of it. The osseous labyrinth is at first entirely separated from the osseous mass of the petrous process which surrounds it, and which is developed before it. It is, however, always applied to it. Its surface then is entirely smooth. The inner face of the osseous mass of the petrous process is also smooth to a certain extent, although more corrugated than that of the labyrinth. The two surfaces soon blend together, but they can be entirely separated in children, and the smooth polished surface of the labyrinth can be demonstrated ; but they afterward become inseparable. The line of demarkation is very evident in every part, particularly in the cochlea, where it is perceived that the prolongations described above are perfectly distinct from the canal formed by the membranous and osseous labyrinths. Thus the osseous labyrinth is developed independent of the osseous substance of the petrous portion. As the external membrane of the membranous labyrinth disappears at the period of its formation, it is not improbable that it changes into osseous substance, or at least that this substance transudes through its external face. In fact, this membrane does not exist for some time with the osseous labyrinth, and may always be easily separated from it : but we are satisfied, from numerous observations, that as the osseous labyrinth is developed around it, it becomes denser, firmer, dryer, and in a measure horny : hence we have been induced to believe that the two modes of formation coexist, that is, that the membrane secretes first the labyrinth, then that an analogous substance being deposited with it, it unites with the layer it had first formed, and becomes its internal layer. The formation of the osseous labyrinth would thus resemble that of the teeth.(l) (1) Ribes has asserted that in the fetus the serum of the labyrinth is reddish, bloody, and exactly fills it. As the infant grows older, it becomes clear, limpid, and less in quantity, and the ear becomes more sensible to sounds. F. T. § 1951. As the organ of hearing is very complex, it presents very numerous and very different anomalies(l) in respect to their essence ; by these the ear is unusually hard or soft, or is entirely deficient. the most interesting in a physiological point of view. As in all other parts of the body, they are more or less characterized by a retarded development, (2) and are also more or less repetitions of what is observed in animals inferior to man. § 1953. 1st. Deviations of form in regard to quantity. The entire absence of the external ear, of which we possess some instances, depends on the permanence of a state which marks the early periods of fetal existence. The anomaly varies a little less from perfect development when the ear is closed, which can exist in different degrees; these lead imperceptibly to the normal formation by the shortness and narrowness of the external auditory passage. The absence of the lobule, or its adhesion with the skin of the head, is the least deviation from the normal state. This state also exists regularly at a certain period of the formation of the fetus. an anomaly of an entirely different character. 2d. Deviations of formation in regard to quality. These are the turning of the ear on the orifice of the external auditory passage, which more or less closes this canal. (4) (1 ) Besides the works of Duvernoy, Wildberg-, and Saunders, already mentioned, which treat also of the diseases of the ear, consult, J. A Rivinus, De auditvs ritiis , Leipsic, 1717.— J. M. G. Itard, Traite des maladies de l’oreille et de l'audition, Paris, 1821. — C. F'. A. Escbke, Diss. de avditusvitiis, Berlin, 1819. outside as in fishes. Sometimes one or more of the little bones of the ear are deficient, or they are too small. (1) Sometimes they are unusually large, thus preserving the distinctive characters of the fetus. They are rarely more numerous than usual. When supernumerary bones exist, they are always very small. They occur particularly between the malleus and incus, and also in the neck of the stapes. 2d. Deviations of formation in regard to quality. The bones of the ear are sometimes formed after a different type, and then are more or less similar to those of certain animals. Thus Comparetti(2) observed in a man, that not only the two stapedes were very small, but also formed by a single branch, with a small base closing the fenestra ovalis, which was very narrow. (3) B. LABYRINTH. When the labyrinth is very imperfectly developed, there is only a single cavity closed externally, which is not divided into the vestibule, cochlea, and semicircular canals, and which does not communicate with the tympanum. (4) This form resembles that of the organ of hearing in the Crustacea and the cephalopoda. Perhaps it is normal also in the early periods of the existence of the human fetus. When the development is more advanced, the cochlea describes fewer turns than usual, (5) even as in reptiles and birds, it appears as a sac-like prolongation, which is not curved on itself. From our preceding remarks, this anomaly should be considered as a continuance in the fetal state. enlarged head or process. The incus has been observed sometimes narrower, sometimes broader, and sometimes with its long branch more or less arched. Rudolphi has described and figured (Diss. sis. observationes osleologicas, Berlin, 1812, tab. i. fig. 15.) a stapes, of which the branch alone communicated with the base, the other being loose, and forming with the preceding an obtuse angle. Lœsecke seems to have observed a similar case ( Obs . anat. Chirurg., Berlin, 1754, p. 15.) Tiedemann has described a stapes found in a newly born infant, which presented neither branches nor opening. It resembled a small pyramid, the base of which represented the plane surface, and from whence a piece of bone arose, slightly depressed, which was articulated with the long- branch of the incus by a rounded process. He has also seen in an adult the two branches of the stapes completely united by a layer of bone, so that there is a slight depression, but no opening between them ( Sur quelques variations dans la forme de l’etricr chez l’homme ; in the Journ. complém. des sc. méd., vol. viii. p. 83. F. T. § 1955. The accidental or consecutive deviations of formation result from an external lesion, which is purely mechanical, or an alteration in texture. Sometimes in hydrocephalus the two external bones of the ear are pushed outward and detached from the stapes, and sometimes even this is unconnected with the fenestra ovalis.(3) § 1956. The alterations of texture in the organ of hearing are principally inflammation and its consequences, among which we must first mention adhesion and suppuration, which frequently affect the external and the internal ear. The buccal orifice of the Eustachian tube is frequently obliterated after scarlatina, or the tympanum and the bones are destroyed by ulceration. The entire or partial destruction of the membrane of the tympanum and very probably also the anomalies in the tumors of the labyrinth, which are thickened, (4) solidified, and changed into a hard body (5) after long affections of the internal ear, (6) belong to this class. The new formations developed in the organ of hearing are : 1st. Accidental ossification , by which the bones of the ear adhere to each other, and obstruct the fenestra rotunda, (7) in which case we also find the bones, particularly the stapes, twice as large as they are generally : the stapes also is fused with the fenestra ovalis,(8) and forms osseous concretions(9) in the membrane of the tympanum. (10) (2) This fact has been observed several times, among1 2 3 4 * 6 7 8 9 10 others by Sylvius, Hoffman, and Arenda. Itard also has seen it: but he thinks that the wasting of the auditory nerve is more frequently the effect than the cause of deafness (toc. cit., vol. i. p. 392.) (5 ) Seeon this subject an important memoir on the physiological relations, by G. F. St. Hilaire, Sur la nature, la formation et les usages des pierres qu'on trouve dans les cellules auditives des poissons ; in the Mém. du Muséum, 1824. (10) Kibes (loc. cit., p. 654) has found the membrane of the fenestra rotunda ossified in a man completely deaf, and destroyed in several subjects, some of whom had not completely lost the power of hearing. This latter circumstance deserves to be remarked, since complete deafness does not result from injuries of the membrane of the tympanum, which is so analogous to that of the fenestra rotunda. According to Pinel’s observations, it would seem that deafness depends on an alteration in the texture of the mucous membrane of the internal ear rather than on any other cause, although he seems to attribute it to the diminution of the fluid in the labyrinth, which in this case is only a consequence of inflammation. (Recherches sur tes causes de la surdité chez les viellards ; in the Archiv, gén. de méd., vol. vi., p. 247.) Among the entirely abnormal formations we must arrange the fungous tumors and the polypi , which are developed principally in the mucous membrane of the auditory passage. ORGAN OP SIGHT. § 1957. The organ of sight ( oculus)(2 ) occupies the upper part of the front of the face, and is situated on the right and left, on the sides and above the root of the nose in the orbit and circumference of this cavity. We distinguish the eye or the globeof the eye ( bulhus oculi) with the muscles which move it and the parts which protect it. (2) Fabricius d’Aquapendente, De visione, voce et auditu , Venice, 1606. — V. F. Plemp, Ophthalmographia , s. tractatio de oculo, Louvain, 1648. — G. Briggs, Ophthalmographia, seu oculi ejusque partium descriptio anatomica, London, 1685. — J. Taylor, Nouveau traité d’anatomie du globe de l'œil , avec l’usage de ses différentes parties , et de celles qui lui sont contiguës , Paris, 1738. — A. Bertrandi, Diss. II. de hepate et oculo , Turin, 1748'. — J. G. Zinn, Descriptio anatomica oculi liumani , Gottingen, 1753. — G. Porterfield, Treatise on the eyes , the manner and phenomena of vision , F.dinburgb, 1759. — M. Horrebow, De oculo humano ejusque morbis , Copenhagen, 1792. — A. Monro, Miscellaneous observations on the structure and the function of the eyes ; in his Treatise on the brain, the eye , and the ear, Edinburgh, 1797. — S. T. Sœmmerring, in Demours, Traité des maladies des yeux, vol. iv. — J. G. G. Voit, Oculi humani anaiomia et pathologia, Nuremberg, 1810. — C. H. T. Schreger, Versuch einer vergleichenden Anatomie des Auges, Leipsic, 1818. — D. G. Sœmmerring, De oculorum humani animaliumque sectione horizontali, Gottingen, 1818. — J. A. Hegar, Diss. de oculi partibus quibusdam, Gottingen, 1818. — C. F. Simonson, Anatomico-physiologicus tractatus de oculo, Copenhagen, 1820. I. EYELIDS. § 1959 The eyelids (palpebrœ) are perpendicular folds situated before the anterior orifice of the orbit, which they close more or less perfectly. They are distinguished into upper and lower. They blend together in the great or internal angle, and the small or external angle of the eye ( cantlii oculi , intermis et cxiernus ), and are separated from each other their entire breadth by a transverse fissure ( fissura palpebrarum). The superior is much greater than the inferior ; a flat ligament formed of transverse fibres several lines long, leaves the great angle of the eye and goes inward between the fibres of the internal portion of the orbicularis palpebrarum muscle ; its internal extremity is broader than the external, and is attached to the upper part of the nasal process of the superior maxillary bone. This is the palpebral ligament ( lig . palpebrarum). destitute of hair. It is continuous on the edge of the eyelids, which is nearly a line broad, with the internal layer which belongs to the internal cutaneous system, that is, to the mucous membranes. This layer is also thin, reddish, and moist. It is termed the conjunctiva. It lines the whole extent of the inner face of the eyelids, is reflected on itself in the parts where these movable folds are attached to the rest of the skin, and is called the tunica adnata, is fitted to the anterior part of the sclerotica , from which it may always be easily separated, and which it covers to the circumference of the transparent cornea. At least it is not possible strictly to demonstrate that it extends also on the anterior face of this last membrane, for if in certain morbid affections a layer rises on the anterior face of of the cornea, this circumstance authorizes us to think, but does not prove, that this layer in question is a prolongation of the conjunctiva. Admitting that this passes really on the cornea, and that it blends with the external pellicle of this membrane without any marks of separation, it does not follow that it possesses in this place the characters of a serous membrane,(l) for the anterior face of the transparent cornea belongs rather to the class of the mucous membranes. (2) Walther has already demonstrated(3) that it is wrong to exclude the conjunctiva OF THE EYE. entirely from among the last membranes. The adhesions(l) between its two opposite faces which have been brought forward to separate it from the other mucous membranes, and which have been used to a certain extent to class it among the serous membranes, are rare and accidental, and supervene probably after suppuration, in which case even the mucous membranes contract adhesions. A. EYELASHES. § 1960. The anterior part of the edges of the eyelids presents three or four irregular ranges of short, straight and arched hairs, which gradually become larger from the two angles of the eye to the centre, and which are termed the eyelashes (cilia). (2) Those of the upper lid are more numerous and stronger than those of the lower. The former are arched from above downward, the latter from below upward. When the lids close they intercross and form from their curve a broad ridge. § 1961. Farther back and nearer the posterior limit of the edge of the eyelids, at about its centre, is a series of openings regularly arranged, which are also larger in the upper than in the lower eyelid, and which do not occupy the entire breadth of these movable lids. These openings lead to the glands of JMeibomius, or the sebaceous glands of the eyelids (Gl. JWeibomiance , s. 'palpebrarum sebaceœ), small, very elongated, narrow, tortuous bursæ, which terminate in sacs generally single, but sometimes divided at their base into several compartments, which are situated perpendicularly below the conjunctiva, between it and the tarsaL cartilages. These glands are filled with a thick, yellowish -viscous substance, called lema, which accumulates around the eyelashes during sleep, and which is easily distinguished by its color from the red conjunctiva. C. PALPEBRAL CARTILAGES. § 1962. Each eyelid contains between the two layers of skin and near its loose edge an oblong cartilage, called the tarsus , which determines its form. These cartilages extend much farther from without inward than from above downward, and they are very thin from before backward. They are much thicker at their loose and straight edge than on their convex portion, which looks to the base of the eyelids ; they extend on the inside only to the lachrymal puncta, and terminate on the outside also a little before the commissure of the two eyelids. Their convex edge and their internal and external extremity becomes at the two angles of the eye a very dense cellular tissue, which is called the tarsal ligament ( lig . tarsi , internum et externum ) ; this unites them to the external and internal edge of the anterior opening of the orbit. § 1963. The eyelids have two muscles which act in opposite directions, the orbicularis 'palpebrarum and the levator palpebrce superiors muscles. The first is common to the two ; the second belongs to the upper eyelid only. The lower eyelid has no special muscle. A. ORBICULARIS PALPEBRARUM MUSCLE. § 1964. The orbicularis palpebrarum muscle, naso-palpébral , Ch. (JVT. sphincter palpebrarum, s. nculi ), is thin, membranous and circular, although a little elongated. It occupies the upper and anterior part of the face and the lower and anterior part of the skull. Consequently it is not by any means confined solely in the eyelids. may be said to leave the inner angle of the eye and to return to it. Besides this origin, several other fasciculi pass before and behind the palpebral ligament, whence it follows that a portion of this muscle is formed by uninterrupted circular fibres. The orbicularis muscle arises above by short tendinous fibres from the upper extremity of the nasal process of the superior maxillary bone, from the os unguis, and the lower and anterior part of the nasal and orbitar portions of the frontal bone. It arises below by similar fibres from the lower part of the inner edge, and from the inner part of the lower edge of the orbit, which are formed by the ascending process and by the body of the superior maxillary bone. Its fibres separate especially in its lower part, and fasciculi are detached from its outer part, some of which go the cellular substance and others enter the zygomaticus minor and the levator labii superioris muscles. The internal part of this muscle which is contained in the eyelids, where it is situated directly below the external cutaneous layer, is much less extensive than the external. Its fibres are straighter, thinner and paler than those of the latter, with which it is always un- B. LEVATOR PALPEBRJE SUPERIORIS MUSCLE. § 1965. The levator palpebrcz superioris muscle, orbito-palpébral , Ch., is very long, thin and triangular. It arises by a short tendon at the base of the orbit from the periosteum which lines the upper part of the optic foramen, and blends in this place with the tendons of the rectus internus and rectus superior muscles. It gradually becomes broader and thinner, advances directly under the orbitar plate, covering first the inner and then the whole of the rectus superior muscle. It finally becomes a very thin tendinous expansion, often scarcety perceptible, part of which is attached to the upper edge of the superior palpebral cartilage, while the other passes between the orbicularis palpebrarum muscle and this cartilage, and extends to its lower edge where it is inserted. great angle of the eye a third which is much smaller and imperfect. The two palpebral commissures differ in form. The external is more pointed than the internal. The latter resembles a small and narrow prolongation of the palpebral fissure towards the nose, the separation of which with the rest of the fissure is marked very evidently by the lachrymal puncta, and which terminates inward in a rounded edge. The third eyelid is found in this space. It has the form of a triangle, the summit of which looks inward and the loose edge outward ; this last is semicircular. It is formed by a fold of the conjunctiva by a small palpebral cartilage situated near its loose edge, and by a considerable number of sebaceous glands united in a rounded or slightly triangular mass, between which are small, straight and very fine hairs analogous to the eyelashes. ticularly on its anterior face. They are called the caruncula lachrymalis. The external and loose part of the third eyelid which passes much farther forward than the caruncula, has been termed the semilunar fold ( plica semi-lunaris) . This part then really possesses all the constituent parts of an eyelid. It differs from the other eyelids by its smallness and in the deficiency of an external layer of skin and of muscular fibres. It is in fact a rudiment of the third eyelid which exists in most vertebrated animals. In fact the perpendicular eyelid of these last differs from it only by its greater size. When wc descend in the animal scale we see that its development is always in an inverse ratio with that of the horizontal eyelids, and that finally it entirely replaces them. II. EYEBROWS. § 1967. The eyebrows ( supercilia ) are short, strong, compact hairs, which gradually increase in size from within outward, and which are arranged in several superimposed striæ. These hairs form a little above the upper eyelid an arch, the convexity of which looks upward. The two arches they describe blend more or less at their inner part. supcrcilii. The corrugator supercilii muscle ( fronto sourcilier , Ch.) is thick and large. It covers the inner part of the upper edge of the orbit. It is covered at its origin by the upper internal part of the orbicularis palpebrarum muscle, and by the internal and inferior part of the frontalis muscle ; it arises by very short tendinous fibres from the frontal bone, below the inner part of the supraciliary ridge. Its fibres are oblique. Its direction is outward, and it gradually becomes thinner. It is so blended, particularly in its external part, with the upper portion of the orbicularis palpebrarum muscle, which entirely covers it, and which may be considered as a deeper layer of this latter muscle. III. LACHRYMAL PASSAGES. § 1968. The lachrymal organs or passages ( organa lachrymalia , s. vice lachrymales), form a special apparatus, the function of which is to secrete and excrete a transparent liquid termed the tears (lachrymce).(l) This apparatus includes the lachrymal gland and its excretory ducts, the lachrymal puncta, and the lachrymal passages , the lachrymal sac , and the nasal canal. We may annex to a certain extent the conjunctiva, as it is uninterruptedly continuous with the excretory passages, the gland, and the lachrymal puncta, and as, strictly speaking, it is only a considerable dilatation of the excretory portion of the lachrymal organ. situated behind the upper eyelid, directly below the orbitar plate. The superior lachrymal gland ( Gl . lachrymalis superior , s. innominata Galeni), is much larger than the other. It occupies the lachrymal depression of the frontal bone. It is triangular, and flattened from above downward. The inferior (Gl. congregalœ JWonroi) ( 1 ) touches at its posterior extremity, the anterior part of the preceding, and extends to the external part of the upper edge of the cartilage of the upper eyelid: Its lobules are smaller and more remote from each other, than those of the upper. Six or seven very small canals arise from these two glands, and go from behind forward, from without inward, and from above downward, and open at the side of each other from without inward, on the inner face of the upper eyelid, near the external angle of the eye. B. LACHRYMAL PUNCTA AND LACHRYMAL PASSAGES. § 1970. The upper and the lower eyelids present each, at the part where the inner angle commences, and where the orifices of the Meibomian glands terminate, an opening, the direction of which is rather more backward, and which may easily be distinguished from those of the palpebral glands and the lids, as its diameter is much larger, and as it is supported by a conical prominence. These two openings are termed the lachrymal puncta (P. 1. superius et inferius). The direction of the upper is downward, and that of the lower is upward. The latter is most generally larger than the other. The lachrymal passages proceed directly on the edges of the eyelids, covered posteriorly by the internal cutaneous laj-er of these lids, and anteriorly by the orbicularis muscle, with which they are so intimately connected, that they are detached from its fibres with great difficulty. The superior first ascends a little outward, in which direction also the inferior descends. In this part of their course they are very narrow. Then after slightly projecting, the superior goes inward and downward, and the inferior upward, and both converge very much. Arrived at the inner angle of the eye, they pass under the palpebral ligament, and open into the anterior and external part of the lachrymal sac, one directly above the other, but by two distinct orifices. They form within this cavity a small rounded prominence. downward. It is covered anteriorly by the inner part of the orbicularis palpebrarum muscle, and is situated above in the lachrymal groove, along which it extends upward into the lachrymal passages by a small cul-desac, and downward into the nasal canal. It descends first from within outward and from behind forward, then, on arriving at the nasal canal its direction is from before backward. In its course its diameter gradually diminishes. It opens into the anterior part of the lower meatus of the nasal fossæ, by an opening which is oblique from above downward and from within outward, and which is provided with a small valve. It is formed of three superimposed membranes. The external is whitish, and is evidently fibrous, and also serves as a periosteum to the bones which receive the lachrymal sac; but it is also very apparent on the anterior side of the upper part of the sac which lodges the lachrymal groove. The middle is thin and cellular : it corresponds to the cellular tunic of the mucous membranes. The internal is thick, rough, spungy, verrucous, and of a deep red. It always secretes an abundant mucus, which oozes through the rounded and oblong orifices of small glands arranged very compactly. This internal membrane is evidently the continuation of that of the nasal fossæ, while that which forms the lachrymal passages is continuous with the conjunctiva, so that it establishes the limit between the eye and the nose.(l) It arises from the posterior superior part of the os unguis, just in advance of the vertical suture between the os planum and the' os unguis. Having advanced three lines, it bifurcates ; one bifurcation is inserted along the upper lachrymal duct, and terminates at its punctum, or near it ; and the lower bifurcation has the same relation to the lower lachrymal duct. The base of the caruncula lachrymalis is placed in the angle of the bifurcation. The superior and the inferior margins of the muscle touch the corresponding fibres of the orbicularis palpebrarum, where the latter is connected with the margin of the internal canthus of the eye, but may be readily distinguished by their horizontal course. The nasal face of this muscle adheres very closely to that portion of the sac which it covers, and also to the lachrymal ducts. The lachrymal sac rises about a line above its superior margin, and extends in the orbit four lines below its inferior margin. The orbital face of the muscle is covered by a lamina of cellular membrane, and between this lamina and the ball of the eye are placed the valvula semilunaris, and a considerable quantity of adipose matter. As the bifurcated extremities of the muscle follow the course of the ducts, they are covered by the tunica conjunctiva. When this muscle is examined from behind, the eyelids being in situ, it becomes obvious that it is concave on its orbital surface, and consequently convex on the nasal ; that the muscle is an oblong body, half an inch in length, and about three lines wide, bifurcated at one end ; and that it § 1972. The globe of Ike eye ( bulbus oculi),( 1) often termed simply the eye, is formed like an almost regular globe. In the adult its diameter is about an inch : its length, however, exceeds its breadth and its height. It occupies the anterior part of the cavity of the orbit, but passes a little before it. It is surrounded in every part by an abundance of fat, and also by the muscles which move it, and which contribute with the optic nerve, and numerous blood-vessels, to retain it in place. It is formed by several superimposed membranes and the humors contained by them. In respect to the form and the texture of the membranes, and that of the nature of the humors, we may divide it into two parts, a posterior and an anterior, the first of which is more extensive than the other. The superior fork, however, has a few of its fibres blended with the ciliaris. In regard to the use of this muscle. Its attachment to the posterior face of the sac is such, that it draws the orbital parietes of the sac away from the nasal, and dilates the sac, from the nasal face of the latter being fixed to the hones. As this muscle has a cylindrical concavity on its orbital side, it is evident that when it contracts the fibres become straight, or nearly so, like the fibres of the diaphragm, and the cavity of the sac is enlarged after the same manner as the cavity of the thorax. A tendency to a vacuum being thus produced by it, the valves or folds of the internal membrane of the sac, permit the vacuum to be filled more readily through the puncta than from the nose; and the puncta being continually bathed in the tears of the lacus lachrymalis, both in the waking and in the sleeping state, the tears are constantly propelled through them by atmospheric pressure. The evacuation of the sac is no doubt accomplished by its own elasticity, and by the contraction of the orbicularis ; probably in a chief degree by the latter, because in persons who have epiphora, or a tendency to obstruction in the nasal duct, the accumulation of tears and matter principally take place at night, when the action of the orbicularis is suspended by sleep. For these reasons we should argue, that this little muscle is active all the time, both night and day. To Dr. Physick I am indebted for suggesting another use for this muscle ; that of keeping the lids in contact with the ball of the eye. Some persons possess unusual voluntary power of this muscle, of which I have seen two examples ; one in a lady ; another in a gentleman, a student of medicine. In each instance the individual could shorten so much the internal angle of the eyelids, as to conceal it, along with the puncta, in the internal canthus of the orbit.” Trasmondi, on the contrary, thinks that it acts on the lachrymal sac and passages, that it compresses the caruncula lachrymalis so as to favor the excretion of the humor formed by its crypts, and that it relaxes or also tenses the membrane, so as to increase or diminish the base of the lachrymal sac, and to force the tears into the nasal canal. ( Notice sur l a découverte de deux nerfs de l’œil humain ; in the Mélanges de chirurgie étrangère , Geneva, 1824, p. 415). Gery {Ibid. p. 453) does not agree with his fellow-countryman, and thinks with Horner, that this muscle serves to adapt the lids to the globe of the eye, and to direct the tears into the lachrymal sac. F. T. (1) C. A. Rudolpbi, Diss. de oculi quibusdam partibus, Gripswald, 1801.— -Id. lieber einige Theile des Auges in his Anatomisch-physiologische Untersuchungen , vol. i. p. 1-30. — Dœllingcr, Illustratif ichnographica oculi humani, VVurtzburg, 1817. — Edwards, Sur la structure de l'œil: in the Bulletin de la soc. philom., 1814, p. 21. — E. Home and F. Bauer, Observations microscopiques sur la structure de V oeil ; in Phil, trans ., 1822, p. 76, and in Archiv, génér. de méd., vol. ii. p. 151. The most external membrane is the cornea , the posterior part of which is the opaque cornea or the sclerotica , and the anterior, the transparent cornea. Next comes the middle membrane, the choroid , the anterior part of which is termed the iris, and below this is a third, the retina, which is a prolongation or expansion of the optic nerve. A. SCLEROTICA. § 1974. The sclerotica, the opaque cornea, or the albugineous membrane of the eye ( tunica sclerotica, s. albuginea, s. cornea opaca), covers the posterior part of the eye, and occupies about five sixths of its circumference. It presents posteriorly, a little nearer its inner side than its centre, a round foramen, or at least it is much thinner there than in its other parts, and there presents numerous small cribriform openings, through which the fasciculi of the optic nerve communicate with the retina. It is terminated anteriorly by a broad rounded opening which recieves the transparent cornea. As it belongs to the class of fibrous membranes it is white, brilliant, fibrous, very elastic and solid. We may forcibly divide it into several layers : but these are united by intermediate filaments. The two faces are smooth. Numerous blood-vessels, the trunks of the twigs distributed to the inner part of the eye, intimately adhere to the external ; some of these vessels perforate it posteriorly, others more anteriorly at about its centre. They all proceed within its substance a greater or less distance, which is proportional to their own volume. choroid membrane. The sclerotica is not equally thick in every part. It generally diminishes much from behind forward. Posteriorly it is about a line thick, and about one half of a line at the edge of the transparent cornea. these insertions. In the place where the optic nerve communicates with the globe of the eye, it unites very intimately with the envelop given to this nerve by the dura-mater. Although it is eight or ten times thicker, and also since they do not differ essentially in regard to texture, § 1975. Among the superimposed layers of the sclerotica, one may be detached more or less easily from the others, and with greater facility in the early periods of life, than in the adult. This very thin layer is a prolongation, not of the pia-mater as has been supposed since Zinn’s time,( 1 ) but of the envelop sent by the arachnoid membrane to the optic nerve, and with which it is evidently continuous. It forms a small bursa projecting inward, around the cribriform plate, through which the optic nerve enters the eye, and is reflected from the circumference of this layer on the inner face of the sclerotica, with which it unites intimately, proceeding with it to its anterior edge. There is then between this layer and the sclerotica, exactly the same relation as between the dura-mater and the arachnoid membrane within the skull and the vertebral column, or, emplojring a more general comparison, as between the hard substances, as the cartilages and the fibrous organs, covered with serous membranes and these membranes. The inner face of this internal layer of the sclerotica, is rather intimately united to the choroid membrane by a loose cellular tissue, and also by the nerves and vessels which pass through the external capsule of the eye. We may, however, especially some days after death, separate and remove the sclerotica, without injuring the choroid membrane. ' B . TRANSPARENT CORNEA. § 1976, The transparent cornea ( tunica cornea , s. cornea pellucida)( 2) which surrounds the anterior part of the eye, differs from the sclerotica in its texture so much, that it is impossible to apply the same term to these two membranes. It represents a segment of a sphere which is a little smaller than that of which the sclerotica is the figure, so that it is more convex and projects slightly on the surface of the latter. It is always a little thicker than the sclerotica, and its thickness is generally uniform, except at its circumference, where it gradually becomes much thinner, but only in a slight extent. Sometimes, however, it is a little thicker in the centre than on the edge. Its posteriorface always describes a concavity which corresponds exactly to the convexity of its anterior face. The conjunctiva extends towards the upper edge and the lower edge of its external face for about half a line, so that this external face is not perfectly round, but slightly elliptical, The upper face, on the (2) B. D. Manchart, Corneæ oculi tunicæ examen analoviico-physiologicum , Tubingen, 1743. — Hoffbauer, Diss. de cornea ejusque morbis, Berlin, 1820. — M. J. Chelius, l’eber die durchsichtige Hornhaut des Augest Carlaruhe, 1818. contrary, is entirely round. It terminates by a circular depression or groove which receives a prominent edge, situated on the limit between the ciliary ligament and the iris. The first is the most common and the last the rarest arrangement. § 1977. The transparent cornea is formed of several layers having between them a limpid fluid which are separated more easily than those of the sclerotica, and which are united by a loose cellular tissue. opacity and collapse of the cornea, which then occur. The posterior face of the cornea is covered by a thin, pellucid, homogeneous and slightly extensible membrane, which tears evenly when forcibly extended and is easily detached from it by a slight maceration or by boiling.(l) This membrane is attached to the edge of the cornea, and does not proceed at least sensibly on the iris. It has been termed the membrane of the aqueous humor (mem. humoris aquei ) I his term is inappropriate, as it docs not seem to secrete the aqueous humor.* (2) § 1978. Directly below the external tunic of the globe of the eye is another membrane of about the same extent and also composed of two halves differing in their organization. The posterior is termed the choroid membrane, and. the anterior, which is much smaller, the iris. (1) B. Duddell, Treatise on the diseases of the horny coat in the eye , London, 1729. — J. Descemet, An sola lens crystallina cataractœ sedes , Paris, 1758. — Id. in the Mem. des sav. étrangers , book i. — Demours, Lettre à M. Petit , Paris, 1767. — The details of the quarrel between Descemet and Demours, in regard to the discovery of this membrane, are given in the Journ. de med ., 1769, 1770, 1771. * Professor Schlemm of Berlin, asserts that the cornea is well supplied with nerves : “ They arise from the ciliary nerves which divide behind the ciliary ligament into a superficial and a deep-seated order of filaments. The latter are larger and more numerous, and are distributed to the iris ; the superficial however enter the sclerotica on a level with the ciliary ligament, from whence they extend forward to enter the groove of the edge of the cornea which is united with the corresponding border of the sclerotica, and traverse the posterior part of the cornea until they become lost by their extreme tensity upon that membrane.” (Am. Journ. of the Med. Sciences, Nov., 1830, p. 211.) § 1979. The choroid membrane (tunica vasculosa, s. choroidea)( 1) corresponds to the sclerotica. It extends from the anterior edge of this membrane to the entrance of the optic nerve for which it presents a rounded opening and to which it is directly united, particularly along the course of the nerves and vessels, in its whole extent by rather a loose cellular tissue. The union between the two membranes is only interrupted here and there by the ciliary nerves and the long ciliary arteries, which proceed between them from behiird forward. tina, although they are in direct contact. § 1980. Near the anterior extremity of the choroid membrane the mucous tissue becomes much thicker in the outer face of the membrane, and forms a whitish ring about one line broad, called the ciliary ligament, the commissure of the choroid membrane , Ch. (L. ciliare, orbiculus ciliaris, circulas ciliaris, plexus ciliaris). This ring attaches the choroid membrane to the sclerotica more firmly than hi the rest of its extent ; but it is united to the sclerotica much less intimately than to the choroid membrane, which is thinner in the part corresponding to it, so that the latter can be easily detached from the opaque cornea, while this is not the case with the ciliary ligament, which may consequently be considered as forming part of it. The internal circumference of the ciliary ligament is bounded by a narrow but very evident white projection, which fils exactly into a groove on the circumference of the inner face of the transparent cornea. B. CILIARY BODY. § 1981. The inner face of the choroid membrane is singularly changed in this place, where it forms the ciliary body ( corona ciliaris, s. orbiculus ciliaris, corpus ciliare, tunica ciliaris). (2 ) In fact on leaving the external edge of the ciliary ligament it forms, inward and for the breadth of about a line and a half, numerous small folds, whence come a great number of slightly prominent rays which go from without inward. Another smaller and more internal circle then succeeds, formed by more distinct folds, the inner edge of which is convex and (1) Ruysch, Ep. an at. xiii. — L. Heister, Diss.de tunica choroidcâ , in the Ease, diss. med., Leyden, 1745. — B. S. Albinus, Dc tunica Ruyschianâ et choroidcâ oculi ; in the Ann. acad., 1. vii., cap. iv. which become more prominent from without inward, and terminate in a rounded edge. These folds, which are termed ciliary processes (processus ciliaris), are fewer in number although very numerous, as there are about seventy. They are however much more remote from each other than the external. Their anterior extremity is loose. They arc attached to the large circumference of the crystaline capsule by the anterior part of their adherent edge. The posterior part of all this region of the choroid membrane adheres very intimately to the external face of the ciliary ligament, for its folds are received into the depressions of this latter, the form of which corresponds exactly to theirs, so that in this part the inner face of the choroid membrane is firmly united to the subjacent parts, and when we attempt to detach it in the recent state the ciliary ligament is generally torn. § 1982. The choroid membrane is soft and thin, but its tissue is firm and solid. On removing the coat of the pigment it appears whitish and slightly transparent. It is almost entirely formed by blood-vessels which are very distinct on its two faces, especially on the external. The long ciliary arteries (A. ciliares longa) are longer and more superficial than the others ; there are generally but two, an external and superior and an internal and inferior. These two arteries are situated more or less nearly opposite each other. After passing through the sclerotica at its posterior part they are situated on the anterior part of the choroid membrane, proceed directly from behind forward without sending off any very large branch, and are distributed in the iris. Hence they do not really belong to the choroid membrane. The short or posterior ciliary arteries, uvéales , Ch. (A. ciliares breves , s. postenores), are much smaller but more numerous than the long. There are usually twenty or more of them of different sizes. They perforate the sclerotica more posteriorly and internally than the preceding, nearer the optic nerve, and soon enter the choroid membrane. They there divide into twigs which are given off at acute angles, frequently anastomose together, especially in the anterior part of the choroid membrane, and form forward, behind the external edge of the ciliary body, a circle composed of a very complex network. The twigs they produce in dividing are parallel, and proceed very closely from behind forward. At the posterior part of the choroid membrane they are situated on its outer face, but towards the centre of the globe of the eye they pass through it and go to its internal face, from the arteries by their course and their larger size. Their branches are very compact, radiate from before backward and from without inward, form large arches, and divide into twelve or fourteen small twigs which pass through the sclerotica at about the centre of the globe of the eye, proceed a few lines from before backward in this membrane, and reunite in four or five larger trunks which pass out of the eye at its posterior part and enter the ophthalmic veins. Four of these trunks are much larger than the rest, some of which proceeding also from before backward, receive the twigs coming from the iris. These veins have been termed from their numerous curves the vasa vorticosa. They are more superficial than the arteries, and are also more external at the anterior part of the choroid membrane and form its external layer. Besides these veins there are others, the long or anterior ciliary veins (r. ciliares longœ, s. anteriores ), which accompany the long ciliary arteries, return from the iris, and receive no considerable ramifications from the choroid membrane.(l) § 1985. The blood-vessels and the mucous tissue which supports them are the only organic elements visible in the choroid membrane. Those fibres which are directed from before backward, and are admitted by several anatomists to exist, have never been seen by us, and even the ciliary body seems only a very complex tissue of vessels. § 1986. The internal face of the choroid membrane does notappears perfectly smooth to the naked eye, but presents, particularly if the eye be injected, numerous small floating flocculæ which give it a downy appearance ; this is much more evident if we use the microscope. These flocculæ are very well developed in the ciliary body. They are mostly formed by a very compact tissue of vessels, particularly in the posterior region of the choroid membrane, the inner face of which is almost entirely covered by them, while they leave it much looser anteriorly. § 1 987. The internal face of the choroid membrane cannot be considered as a special membrane in man, as we cannot divide it into two layers. Ruysch first asserted this opinion, while his son termed this coat the tunica Ruyschiana. It is also incorrect to admit as the villoglandular tunic {2) or the supra-choroid membrane ( membruna suprachoroidca){3), another membrane situated on the outside of the choroid, which would be the second middle tunic of the eye, or even the third, Finally it is still more incorrect to represent the choroid coat as formed by live superimposed layers, (2) of which the second, third, and fourth form the proper choroid membrane, and the other two the two membranes mentioned C, IRIS. § 1988. The im( 3) is a circular membrane perforated in its centre with a rounded and nearly concentric opening, termed the pupil. This opening is a little narrower on its inner side, which looks towards the nose, than in the rest of its course, (4) and its external edge is attached to the anterior edge of the choroid membrane, viz. to the ciliary ligament. Finally, it is entirely loose in the chamber of the eye, where it forms a transverse septum extended from above downward and from light to left, which divides this chamber into two compartments, an anterior and a posterior , communicating by the opening of the pupil. The iris forms the posterior wall of the anterior chamber of the eye, and the transparent cornea forms its anterior wall. It constitutes, on the contrary, the anterior wall of the posterior chamber, the posterior wall of which is formed by the anterior face of the cryslaline lens, and the anterior edge of the ciliary body. The posterior wall of the iris is also termed the uvea. In man it is straight and not convex anteriorly, as has been asserted.^) It is nearer the anterior face of the crystaline membrane than the posterior face of the transparent cornea.(6) The space on its external face where it is greatest, between it and the cryslaline membrane, is not even half a line, but in the centre it is only a quarter of a line. Its centre is about a line distant from the transparent cornea, but its outer edge is much nearer this membrane. Its extent from without inward varies extremely It is not only often morbidly dilated to such an extent that the pupil almost entirely disappears, and sometimes contracts so much as to be invisible or nearly so, but also in the normal state it dilates and contracts rapidly under the influence of certain external and internal causes. (7) By carefully ficielle, Paris, 1812. (4) Winslow, Observations sur la mécanique des muscles obliques de l’œil , sur l'iris, &c. ; in the Mém. de Paris, 1721, p. 4G3. — Littleton, Sur les causes d’où dépend la largeur de la pupille ; in Bradley, Med. and phvs. Journal, vol. xxxvi., examining all the circumstances which belong to these two phenomena we conclude that the active state of the iris js that of dilatation, the passive that of contraction § 19S9. This membrane is much thicker in its larger and external than in its internal part, where it seems to be divided obliquely from without inward and from before backward, and terminates there in a thin edge. The most internal part excepted, the iris is three or four times thicker than the choroid membrane. Its external and internal edges are more deeply colored than the intermediate parts. The darkest part of the membrane is a small portion of the inner surface situated a little on the outer side of the inner edge. This dark place and the portion of the iris between it and the pupil is called the small or the internal circle ( annulus minor , s. internus) . The rest of the membrane is termed the great or the. external circle ( annulus major, s. externus). The whole of the anterior face of the iris is entirely colored. The posterior is colored only in the portion corresponding to the small circle : all the rest is whitish, but covered with a dark mucus (§ 1997), The anterior face is the seat of the peculiar color of the eyes. It is every where covered by very minute and differently colored flocculæ, which with the streaks of pigment abovementioned on the posterior face are the grounds of the different color of the eyes, § 1990. We observe both on the anterior and the posterior face of the iris circular fibres which are slightly undulatory, and longitudinal fibres which radiate from without inward. The first are particularly evident near the outer and inner edge. The others are more distinct on the anterior face ; they are larger and more perceptible in the great than in the small circle Some of these fibres are whitish and alternate with others less manifestly gray. The first divide frequently at acute angles into a considererable number of small branches, which anastomose on the outer circumference of the small circle, giving rise to arches which are convex forward, and thus form a complex crown from which smaller and closer longitudinal striæ emanate ; these radiate in the internal circle to the edge of the pupil, iridis, Gottingen, 1785. — F. llildcbrandt, De motu iridis, Brunswick, 1786. — Doemting, Ueber die Ursache der Bewegung der Regenbogenhaut ; in Reil, Archiv. Jur Physiologie , vol, v. — Oaldani, Intorno di movimenti dcWiride ; in the Mem. della soc. ital., vol. xiv., pt. 2, p. 101-114. — C. A. F. Kluge, Diss. de iridis motu, Erford, 1S06.— S. S. Guttentag-, De iridis motu, Breslau, 181 5. — Littleton, On the couses which influence the sise oj the pupil ; in the Land. mcd. and phys. journal, vol. Ivi , 1816 p. 89, 265, — E H Weber Traci ulus dr motu iridis, Lcipsp • 1821, § 1992. The nerves of the iris (JV', ciliares)( 1) arise from the first branch of the fifth pair, from the sixth pair and the great sympathetic nerve, are about twenty in number, and perforate the sclerotica a little behind the centre of the great diameter of the eye, pass some lines even in the substance of this membrane, are then situated between it and the outer face of the choroid membrane, adhere but slightly to these two coats, proceed from behind forward without giving off any branch, and arrive at the external edge of the ciliary ligament., directly behind which they generally divide at an acute angle into two branches. These branches go forward on the anterior face of the chorokTmembrane under the ciliary ligament and arrive at the anterior face of the iris, where they form the whitish and radiating filaments there observed ; in the course of . these are rounded filaments which are perhaps ganglions. The ciliary nerves are unusually large in proportion to the iris, and hence this membrane is one of the parts of the body, if not the very part, which possesses the most nerves. anterior ciliary vessels. E-ach of the two long ciliary arteries divides below the ciliary ligament into two branches, which go to meet the two corresponding branches of the other arterial trunk, and which by anastomosing with them form on the external edge of the iris a crown slightly convex forward, from which numerous twigs arise ; the latter radiate towards the inner edge of the membrane and still bifurcate, communicating here and there by transverse ramuscules. They anastomose together on the outer edge, of the internal ring so as to form at the opening of the pupil a more or less concentric circle ; from this, new radiating twigs arise and go to the small circumference, but several of them however come directly from the rays of the great external arterial circle. Besides the arterial twigs, the iris also contains many little veins which enter some into the long ciliary veins and others into the vasa vorticosa. As they cannot be filled except by injecting them through the arteries, or as when injected through the venous trunks, they are filled less perfectly than the arteries, the veins seem fewer and form but small arches. (2) which they seem but loosely attached. They certainly carry red blood, since the membrane [bleeds when wounded, and their reddish color is very evident in the eyes of albinos, where the pigment continues colorless from a primitive deviation of formation. (3) to it. They assert that some of the fibres are radiated and others circular : the first extend from the external to the internal circle, where Ruysch thinks that they are even attached by small tendons : the circular form most of the internal circle of the iris. (5) In contracting, the longitudinal fibres dilate the pupil, while the circular contract it. Beside the circular fibres which are admitted by Monro and Ruysch, we have sometimes observed on the anterior face of the iris, towards its outer edge, some very evident circular fasciculi, corresponding to those discovered in the same place in the eye of the ox by Monro ;(6) but neither the anatomy, nor the observation of the vital phenomena of the iris, seem to us to justify the admission of radiating longitudinal fibres. § 1996. The iris in man can be divided, but not naturally, into two layers, an anterior or the proper iris, and a posterior or the uvea, and these cannot be separated except in small portions. It is also uncertain whether its anterior face be lined by a prolongation of the membrane of Demours ; at least it is here also much thinner than on the posterior face of the transparent cornea, and its nature is different. § 1 997. Opinions vary in regard to the manner in which the iris and choroid membrane are united. Some assert that the iris is a prolongation of the latter ; others think that it should be regarded as a distinct membrane. origin and arrangement from those of the choroid membrane. 4th. The difference between the two membranes in respect to their vital phenomena, since the iris is highly contractile, while the choroid membrane possesses no contractility. We may also add that the great edge of the iris is easily detached after a maceration, which does not continue long enough to destroy the continuity of the tissue either of this or of the choroid membrane D. PIGMENT, § 1997. The two faces of the choroid membrane and the posterior face of the iris or the uvea, in the normal state, are covered with a brownish colored substance, termed the pigment ( pigmentum nigrum).(]) In some parts’, particularly on the posterior face of the iris, this pigment can be detached in a greater or less extent as a fine and coherent membrane. In some places, particularly on the inner face of the ciliary body, especially between the processes, and the posterior face of the iris, and generally in the internal regions, it is more abundant, deeper in color, and more attached to the adjacent parts. There is less on the external than on the internal face of the choroid membrane, although that which exists there does not differ essentially from that found in other parts. There is none on the posterior part of the inner face of the choroid membrane around the opening which gives passage to the optic nerve, so that the choroid coat is white in this place. The pigment is composed of a peculiar mucous substance and of another coloring substance, the first of which connects all the molecules together, so that they have the form of a membrane. In regard to mechanical structure, this coloring substance is composed of globules. These globules are not perfectly black, but only present occasionally small points of a deeper tint. Their form is irregularly round They arc smaller in the ciliary processes, but are arranged in several superimposed layers more uniformly black. In regard to their chemical composition, they contain a considerable quantity of iron and also of carbon, which forms almost half of them, so that of all parts of the body they contain the most of this elementary substance. (2) The iron is the cause of their heaviness but not the source of their color, since the quantity of this metal in the reto mucosum of the skin of the negro is small, and even leas than in that of the Caucasian race.(3) The pigment is essentially so similar to the retc mucosum, that we may admit they arc the same, whence it follows that the pigment is not a secreted fluid but a solid tissue, an organic element possessing a special form. (1) Morulini, De oculi pigmenta ; in the Comm. Donon., vol. vii., p. 29. — Elsaesser, De pigmento oculi nigra, Tubingen, 1800. — L. Gmelin, IJiss, sistens indagalionem chimicam pigmenti nigri oculorvm taurinorum cl vilulinurum , adnexis quibusdam in id animadversionibus physiologicis, Gottingen, 1812.— F, Monclini, Sul nero pigmento dell' occhio ; in the Opuscoli scicntijiclii di Bologna , 1818, l'asc, vii-, p 15-27. — Berzelius, Djurlcemi, ii., n 201 C. KETINa. § 1998. The third distinct membrane of the eye is the retina. { 1) It is the expansion of the optic nerve, the anterior extremity of which contracts much in passing through the sclerotica, but more gradually and more insensibly at its inner than at its outer part, so that the nerve describes an arch much larger outward than inward. Before the anterior extremity of the optic nerve the sclerotica presents a surface with numerous foramina, through which the fasciculi of the nerves pass. Beyond this cribiform plate the extremity of the nerve forms a small mammillary prominence, from which the expansion of thç retina arises ; this terminates forward at the posterior extremity of\he ciliary body by a straight edge more or less evidently enlarged, which is unconnected with the crystalline capsule. (2) § 1999. The retina is white, thin, homogeneous, and destitute of fibres, equally thick in every part, excepting one small point of its extent posteriorly. It is composed, in a measure, of two layers, an external, which is medullary, and an internal, formed by cellular tissue and vessels. The latter separates the medullary layer from the vitreous body. We cannot however insulate the two layers from each other so as to obtain one alone in the form of a connected and coherent whole, although the internal appears in this form when putrefaction has destroyed the medullary layer. Hence we cannot consider the retina except as formed by the union of two special and distinct membranes ; but We really find on its external face a very thin membrane^) very analogous to the serous membranes, which seems to us (2) Several old anatomists, particularly Winslow, Cassebohm, Ferrein, Lieutaud, and Haller, whose arguments have been collected by Zinn ( loc . cit., p. 114), and Monro among the moderns (toc. cit., p. 96), have asserted that the retina passes below the ciliary body, and that it extends io the great edge of the crystaline capsule, to which it is attached. But careful dissections have led us to embrace the contrary opinion, which has been supported by Morgagni, Zinn, and some of their predecessors. Monro says that we can prove that the retina extends to the crystaline humor : 1st, by resting the eye on the transparent cornea, and there making a transverse section which includes all the membranes with the vitreous body ; 2d, by raising the ciliary body and carefully removing the pigment with a pair of forceps. But in following these two processes we have always recognized that the retina terminates evidently at the posterior extremity of the ciliary body, arid we have even found that the layer still partially covered by the pigment, which extends from the hyaloid membrane to the crystaline capsule, was more transparent than the retina. The eyes of the fetus are better than those of the adult to demonstrate that Monro’s opinion is false, because in them the retina is more opaque, and the external wall of the canal of Petit is thinner. (3) Jacob, Newly discovered membrane in the eye; in Thomson, Annals of philosophy, July, 1818, p. 74; Phil, trans., 1819, p. 30Ö; Juurn. compl. des sc. méd., vol. xi., p. 187. — Jacobson, Mémoire sur une humeur peu connue de l’œil, et sur les maladies auxquelles donnent quelquefois lieu les changemens survenus dans sa sécrétion ; in the Act. soc. reg. med. Hafn., vol. vi. ; and Bull, de la soc. méd. d’ Emu/., September, 1822. — G. Mirault, Sur une hydrophile puiiiculiirc au globe de l’œil ; in the Archvo. gén. de méd., vol. jj., p. 46. choroid membrane and the retina. § 2000. The retina is extended on the vitreous body, and forms there no fold, except in a small extent of its posterior part, at some distance from the entrance of the optic nerve, and on its outer side. The direction of this fold is transverse from within outward. It commences at some distance from, or directly at the side of the entrance of the optic nerve by a small point, and is terminated by a blunt extremity. It is generally from a line and a half to two lines long. It is commonly single, but sometimes also it is double. In some subjects it is deficient.(2) Home asserts even that it is never natural, and that its formation depends on the more intimate union in this place between the retina and the hyaloid membrane. But the error of the English anatomist is proved by the facts that the fold is observed even when the connections between the two membranes are unaltered, and that it is much more evident in youth than subsequently. The retina presents at the same place a yellowish spot of the same size, which is darker in the centre than on the edges. It is generally one line high, and from one and a half to two lines broad. But it has not the same extent and degree of color in every part, although these two peculiarities are not necessarily connected with the sense of vision. The retina is much thinner in this place than in the rest of its extent, particularly in the centre of the yellow spot, where some admit the existence of a foramen, while others, and according to our dissections more correctly, think that there is a place entirely destitute of medul lary substance, of an oval form and surrounded with smooth and distinct edges. mor is compressed to push the fold outward and to efface it. (1) Ruzzi, in the Opusc. suite scienze e sullc aril, Milan, vol. v., 1784, and vol. vii. — Scemmcrring', Dc foraminc centrait limbo luleo cincto retinœ humancc ; in the Comm. soc. Gott., vol. xiii., 1795 -1798. — P. Michaelis, Buber einen gelben Fleck und ein Loch in der Ncrvenhaul des menschlichen Auges ; in the Journal der Erfindungen, part xv., p. 1-17, 1796, and cah. xvii., p. 133. — J. C. Reil, Die Falle , der gelbe Fleck und die durchsichtge Stelle in der Retzhaut des Auges ; in Ihc Archiv. Für die Physiologie, vol. ii., p. 468-797.- — E. Horne, An account of the orifice in the retina of the human eye ; in the Phil. Irans., 1798, p. ii. — Exposé des résultats de plusieurs recherches sur la lache jaune, le pli cl le Irou central de la rétine, d’après deux mémoires communiqués par Marc et Léveille ; in the Mémoires de la soc. méd. d’Em., vol. i., 1802, p. 364-397. — J. M. § 2001 The posterior part of the eye is occupied by the vitreous humor or body ( humor vitreus , s, corpus vilreurn), which corresponds in its situation to the choroid membrane and the retina.(l) This humor is perfectly transparent, thin, and formed almost entirely of water, which contains a small quantity of the hydrochlorates and the lactates, with still less of albumen and soda. (2) It is contained in a special, very thin, delicate, transparent membrane, which every where surrounds it, and which is termed the hyaloid membrane ( tunica hyaloidea). This membrane sends internally numerous prolongations in the spaces of which the liquid is contained as in so many cellules. The union of the membrane and of the liquid which forms it, is properly speaking, the vitreous body. This body presents on its anterior face a slight cavity which is connected with the crystaline capsule, the posterior part of which is situated there, and adheres to it so intimately in the normal state that it cannot be detached from it, at least when the eye is perfectly fresh, without tearing the hyaloid membrane. 2002. Eetween the great edge of the crystaline capsule and the anterior part of the hyaloid membrane, a little behind the anterior edge of this latter, is a thin layer, termed the ciliary layer ( lamina ciliaris. zonula Zinnii), which is extended like a bridge on the most anterior part of the vitreous body, in connection with which it circumscribes a triangular space, the base of which is formed by the posterior part of the circumference of the crystaline capsule, while the two branches are constituted, one by the layer, and the other, by the most anterior pait of the vitreous body. This empty space surrounds ihe crystaline pmd the vitreous body It is termed the canal of Petit ( canalis , s. circulas Petiti) It is easilydemonstrated by inflating it with air. tween the vitreous body and the retina an empty space, in the centre of which is the central artery of the retina, termed by him the area Martcgiani, in honor of his father. J. Cloquet seems to admit the existence of this deviation, for he says (De la squelettopée , Paris, 1S19, p. 72,) that the hyaloid membrane is reflected on itself on a level with the enhance of the optic nerve into the eye, to form a canal which passes from behind forward directly through the vitreous body. He proposes to call this passage the hyaloid canal, and asserts that it always exists in man. P. T. (2) According to Berzelius (Animal fiuids ; in the Med. chir. Irans., vol. iii., p. 253), one hundred parts of the vitreous humor contains 98,40 of water, 0,16 of albumen, 1,42 of the hydrochlorates and lactates, 0,02 of soda and an animal matter completely soluble in water. The ciliary layer presents numerous fissures, the direction of which is from before backward and «from within outward, because it corresponds exactly to the inner face of the ciliary body, which is intimately united with it, and the folds of which are situated in its depressions. Its external face seems blackish after the ciliary body is removed, because the pigment remains attached to it there. When the canal of Petit is inflated, it is raised, its grooves become more superficial, and its external face seems formed of rounded or triangular eminences which project but slightly and are near each other. This layer is thicker than the hyaloid membrane ; still as it is united with this latter, and as the posterior edge of the layer is continuous with it, we have reason to say that the hyaloid membrane is divided at its anterior part into two layers, of which the external gives rise to the ciliary layer, while the internal is adapted to the posterior face of the crystaline capsule. Ribes(l) asserts that canals exist between the ciliary layer and the ciliary body, which canals conduct the aqueous humor in the chambers of the eye, and take it up again from these two cavities. He supports his opinion by the dilatation of these pretended canals in an eye affected with hydrophthalmia, and the escape of the vitreous humor, when the eye is suspended by the optic nerve, after removing the transparent cornea. But these facts do not demonstrate it sufficiently. The first phenomenon depends probably on the general accumulation of serum in the eye, as there is also a considerable collection of serum between the crystaline lens and the vitreous body. We have every reason to think that the second depended on the pressure of the vitreous body on a part which ought to yield more easily after cutting the transparent cornea. III. CRYSTALINE LENS. § 2003. The crystaline lens ( lens crislallina)(2) is a soft, rounded body, perfectly transparent in the normal state, the breadth and height of which are almost double its thickness, and the posterior face of which is much more convex than the anterior ; at least an inverse relation between its two faces rarely exists, and they are more frequently similar. The posterior face is generally a segment of a sphere about from six to nine lines in diameter, while the anterior is a segment of a sphere about five lines in diameter. (21 A. F. Walter, De lente cristallina oculi humani, Leipsic, 1712. — Petit, Mémoire sur le cristallin de l'œil de l'homme , des animaux à quatre pieds , des oiseaux et des poissons ; in the Mém. de Paris , 1730, p. 4-33. — S. G. Sättig, De lentis crystallines structura fibrosâ, Halle, 1794. — B. F. Bacrcns, Diss. sistens lentis crystallina : monographiam, 1819.— Leiblcin, Bemerkungen über das System der Krystallinsc bey Saughthieren und Vögeln, Wurzburg. 1821. The thickness and the convexity of the crystaline lens are not always in the same proportion, as there is no constant relation between these two qualities and the breadth and height of the lens. differ very much in form This body is situated before the vitreous body, the concave anterior face of which receives its posterior face, below the ciliary body, the internal face of which is partly attached to its great edge, It is situated behind the iris, with which it is not connected. It however is not loose. A thin but solid membrane which is transparent and much thicker than that of the vitreous body exactly envelops it in every pavt.(l) This membrane, termed the crystaline capsule ( capsula cristallina), is the medium of connection between the crystaline lens and the adjacent parts. § 2004. The crystaline lens is formed of two substances, one external and soft, the other internal and harder. These two substances blend together imperceptibly. The first is termed the cortical layer , and the second the nucleus. The cortical substance can be easily separated from the nucleus by crushing it between the fingers. A special process is necessary to demonstrate this texture : but when the most complex means are emploj'ed, the crystaline lens is proved to be much more complicated than it seems at first view, and it may constantly be reduced into a certain number of parts. (3) In fact by maceration and by the action of acids this body is divided in its whole extent from before backward into several triangular segments, the summits of which are turned inward and the bases outward, and which unite in the centre of the lens. Besides each segment also divides into numerous small laminæ, which are situated one above another from without inward, and which cover each other like the coats of an onion. These layers are reflected from before backward on the outer edge of the crystaline lens, in the centre of which they accordingly terminate by two points, an anterior and a posterior. (2) Graefe, Ueber die Bestimmung der Morgagnischen Feuchtigkeit der Linsenkapsel und des Faltenkranzes ; in Reil, Archiv, für die Physiologie, vol. ix., p, 225-236, and in Abhandlungen der Erlanger Soc., vol. i., p. 309-396. (3) A. Leeuwenhoek, De formatione humoris crystalline in variis animalibus, de substantia fibrosa quæ in oculo apparct, &c. ; in the Arc. nat. detect., Delft, 1695, p. 70. — Morgagni, in the Epist. anat., A. 30, 31, 32, 33.— Sättig-, De lentis crystallina: structura fibrosa, Halle, 1793. — Young, in the Phil. Irans., 1793. — Monro, On the structure of the body of the crystaline lens, and whether the fibres which enter into its composition are muscular ; loc. cit., p. 85. Their anterior half is often detached from i he posterior, and the whole crystalinc lens seems more or less evidently divided into an anterior and a posterior half by a fissure which extends from the circumference to the centre. The layers which compose the crystalinc lens are united by fibres which extend from one to another. They are likewise composed of fibres, the direction of which is parallel to their proper longitudinal diameter. These fibres consequently commence at the centre of the crystaline lens. Thus the tissue of the crystalinc lens is lamellar and fibrous.(l) lens and its capsule. The segments of the crystaline lens in respect to their thickness and their lamellar texture, are more distinct on its outer than on its inner side. The fibrous texture is more evident in the inner part. § 2005. The crystalinc lens almost entirely dissolves in water, ex cepting a small quantity of a transparent and insoluble membranous substance. Berzelius has found in it of one hundred parts: of water, 58.0 ; of a peculiar substance, 35.9 ; of hydrochlorates, lactates, and animal matter, all soluble in alcohol, 2.4 ; of animal matter, soluble only in water, with some phosphates, 1.3; of insoluble membranous residue, 2.4. (2) It is particularly worthy of notice that, excepting the color, the peculiar substance which is coagulated by heat is perfectly similar in chemical composition to the coloring matter of the blood. It contains a little iron, while there is much carbon and iron in the pigment. The blood then seems to be decomposed, as the aqueous and vitreous humors contain only the water which contributed to form it. Hence why these two humors do not coagulate. The central artery of the retina is distributed in great part by its anterior branches on the posterior face of the capsule, for its last ramifications on arriving at the anterior edge of the vitreous body are reflected from without inward, and converge towards the centre of this face ; but there are also several small ones which pass on the external edge of the capsule and go on its anterior face. several compartments by internal septa, like those of the vitreous body ( Djurkemi , vol. ii., p. 212). Finally, he observes, and justly, that this body cannot be referred to the class of fibrous organs, as has been done to a certain extent by Mayer ( lieber Histologie, p. 13), and by Heusingcr unrestrictedly {Histologie, part i,; p, 42), since it is entirely soluble in water. F. T. tomose there with the ramifications of the central artery of the retina. In the fetus they send off from behind forward numerous ramuscules, which are distributed on the posterior face of the pupillary membrane. Finally the arteries of the capsule, especially those which arise from the central artery of the retina, send several very minute twigs to the lens which are distributed between its laminæ, so that the latter are not nourished, at least entirely, by absorbing the liquid which surrounds them. Veins have not yet been strictly demonstrated in the crystaline capsule, although they are known to proceed on its posterior face. The latter empty into the veins of the choroid membrane, with which they open on the external face of the ciliary lamina. (2) B. AQUEOUS HUMOR. § 2007. The aqueous humor of the eye ( humor aqueus) is a perfectly clear and transparent fluid which fills the two chambers. It is composed almost entirely of water, (3) and is formed very rapidly. from the floor of the orbit ; the sixth comes from the lower part of its anterior circumference. They surround the sclerotica, to which they are attached and blend with it. (5) (3) Berzelius ( Djurkemi, vol. ii., p, 208) has found, in one hundred parte, 98.10 of water; some marks of albumen; 1.16 of hydrochlorates and lactates; and 0.75 oi animal substance, soluble only in water. and 445. (5) The aponeuroses which terminate them have been considered, but wrongly, as a special membrane between the conjunctiva and sclerotica. (É. Home and P Smith, Philos ; irons., 1795, no, i., p. 1Î, and no. xii., p, 262.) I STRAIGHT MUSCLES. § 2009. The straight muscles of the eye (M. recti Irnlbi oculi ) are the superior , the internal, the external, and the inferior ; but beside these names, founded on the changes they cause in the situation of the globe of the eye when they contract, they have received others also, drawn from the expression they give to the countenance, and from the state of the mind which their action designates. Their common character, is that they all arise from the floor of the orbit by a short and thin tendon, and are attached to the anterior part of the circumference of the sclerotica by another thin but broad tendon. I. RECTUS SUPERIOR. § 2010. The recites superior muscle (M. rectus oculi superior, s, attollens, s. superbus), arises from the periosteum of the orbit, between the optic foramen and the upper sphenoidal fissure, between the upper part of the optic foramen and the sheath of the optic nerve, directly below the levator palpebræ superioris muscle. It goes forward, resting on the upper part of the globe of the eye, becomes broader and thicker from behind forward, and is attached by a broad but thin tendon, to the sclerotica alone, two lines above the transparent cornea. II. COMMON TENDON OF THE OTHER THREE STRAIGHT MUSCLES OF THE EVE. § 201 1 . The other three straight muscles of the eye arise partly by a common tendon, or from a ligament which extends from the inner extremity of the sphenoidal fissure, to two or three lines before this point III. RECTUS EXTERNUS. § 2012. The rectus externus muscle (M. oculi rectus externus, s. ab duccns, s. indignatorius ) arises by two heads. The lower, the larger, comes from the external face of the common tendon, where it adheres very intimately to the tendon of the rectus inferior muscle. The upper is much smaller, and is blended with the tendon of the rectus superior muscle, arises from the portion of the sphenoid bone comprised between the optic foramen and the commencement of the sphenoidal fissure. Hence, the muscle proceeds along the centre of the external wall of the orbit, situated on the periosteum, and is attached by a thin tendon to the outer part of the edge of the sclerotica, some lines from the edge of the transparent cornea. It is broader at its centre than in the rest of its course, and is much flatter and thinner from without inward than from above downward. 2013. The rectus inferior or the depressor oculi muscle (J\I. rectus oculi inferior , s. deprimens, s. Iiumilis), unites with the lower head of the rectus externus and rectus internus muscles, arises from the common tendon, and never comes from the sheath of theoptic nerve. It goes from before backward, and from above downward under the optic nerve, and is attached to the sclerotica. § 2014. The rectus internus muscle (JMT. rectus oculi internus , s. adducens , s. amatorius , s. bibitorius) arises by two heads. The inferior or external comes from the upper and internal part of the common tendon. The superior or internal is the larger, and arises from the inner part of the sheath of the optic nerve. This latter blends with the origins of the rectus superior and the levator palpebræ superioris muscles. Thence the muscle goes inward and forward, along the inner wall of the orbit, from which it is separated by a layer of fat. Its short and thin tendon is attached to the inner part of the circumference of the sclerotica. the posterior part of ihc inner face of the internal wall of the orbit, belorc the optic foramen, and also arises from the sheath of the optic nerve by a thin and short tendon Thence it goes upward and forward along the upper edge of the internal wall of the orbit, and becomes near its anterior extremity, a long rounded tendon. This tendon immediately enters into a small cartilaginous layei about two lines long and broad, which is reflected on itself, and thus represents a semicanal, open upward, forward, and backward, and forms a pulley, the anterior edge of which becomes a pointed prominence, while the upper edges arc attached by ligamentous fibres to the upper part of the internal wall of the orbit. 2017. The obliquus inferior muscle, petti oblique , Ch (M. oculi obliquus inferior ), the shortest muscle of the eye, differs from the other muscles in its origin and direction. It arises by a short tendon from the inner extremity of the lower edge of the orbit, goes upward and outward, then becomes a short and broad tendon, which ascends below the anterior part of the rectus extemus muscle, and between the muscle and the globe of the eye, and is attached to the sclerotica, some distance behind the tendons of the recti muscles, between that of the extemus and that of the superior. FUNCTIONS OF THE EYE. §2018. The eye represents ah optical instrumental) composed of several transparent substances situated successively horn without inti) G. G. Ploucqùct, Dits, sislens momenta quudam physiologica circa visum, Tubingen, 1797. — J. Campbell, iu Thomson, Annals of philosophy, vol. x. p. 1 7—29.— Dunglison, ibid., no. GO. p. 432.— T. Young, Of the mechanism of the eye; in the Phil. Irans., 1801, p. 81. — E. Hall, iu the Journal of sciences and the arts , no. x. p. 249-257.— A. Horn, The scat of vision determined , London, 1815. — M. T. Muhlibach, InmdsUio de visûs sensu, Vienna, 1816..— J. Purkinje, Beytrage sur Kenntniss des lichens in siihjehtircr Hinsicht, Prague; 1810 Troxler, in Himly, Ophthal Bibi, ward, which differ in density, although in all, this is greater than that of the atmosphere. The rays of light which enter it gradually converge on- passing through it, so as to form but one fasciculus, which paints the image of the object at the bottom of the eye on the retina. The impression upon this membrane extends to the brain along the optic nerve, and there produces' the sensation of sight. The transparency of the centres which form the eye, the sensibility of the retina, and the conducting power in the optic nerve, are then the principal conditions necessary to sight. The opacity of one or several of the centres which concur to form the eye, the paralysis of the retina and of the optic nerve, the alterations in the texture of all these parts, the abnormal productions which are developed within or around them, consequently alter or destroy the sense of vision. The globular form of the eye favors the refraction of rays of light. Hence, why the general form of the eye and of its different parts very much influence the distance at which objects are seen clearly. When the eye is very convex, the rays of light are forcibly refracted, and we cannot discern objects which are near (myopia). When the eye is flattened the refraction is. less, and only- distant objects are seen clearly ( presbytia , presbyopia). Hence, why myopia belongs only to youth and infancy, and presbytia to old age. The eye possesses also the power of modifying its form, the relations of its constituent parts, its situation, and its direction, either to obtain a distinct view of objects situated at different distances, in a ray of a certain breadth, or to see without moving the head or body, those which occupy the different points of a portion of a surrounding sphere. This last effect is produced by the action of the six muscles of the eye. The other depends on the contraction of the muscles, partly on the modifications in the secretion and excretion of the humors of the eye, partly on the action of tjie ciliary body, since these three causes united change the curve of the transparent cornea and the crystaline lens, as also the situation of this latter in regard to the cornea and the base of the eye.(l) The dark color of the pigment tempers the violence of the impression which the light would otherwise cause on the retina, which is extremely sensible, (2) for this black vol. i. p. 21—99. — Meyer, Das Auge, ein Hohlspiegel ; in Deutsches Archiv fur die Physiologic, vol. v. p. 54. — M. G. Plagge, Neue physikalische Ansicht des Sehens: ibid., vol. v. p. 97. — Id. Neuer Bcy trag zàr Lehre von Sehen: ibid., vol. vii. p. 213. — E. E. Rœdenbeck, Quœdam ad Iheoriam visus pertinentia, Berlin, 1822. the crystaline lens displaced, and that the clearness of vision of objects situated lrom two hundred and fifty millimetres to any distance, however great, depends only on their apparent diameters, and on the transparency of the air between. ( Réfutation de lapretendue nécessité mathématique du déplacement du cristallin pour conserver constante la distance focale de l'œil: in the Journ. de physiol, experirn., vol. iv. p. 260.) F. T. determined that but a slight sensation is produced when this membrane is touched by a needle, and that even on scraping it, the pain is but slight, and not to be compared with that caused by pricking the surface of the eye. (De l'influence de La cinquième paire sur la nutrition cl les fondions de l’œil: in the Journ. dephys. expér., vol. iv. p. 176.) This physiologist lias also determined that the section of the two nerves ot the fifth pair causes the loss of sight. F. T. layer absorbs a part of toe rays of light. This is the real function of the pigment, since vision is weak and imperfect when it has not its usual color. The iris also serves to moderate the intensity of the light which enters the eye, since this membrane dilates, and thus contracts the pupil, when the light is very vivid, or when we look at an object near, while it contracts and thus enlarges the pupil, when the light is weak, or when we look at rather a distant object. pregnancy as a black spot. But at this period the globe of the eye is still exposed, for the eyelids do not exist. They begin to appear during the tenth week, in the form of narrow bursæ, which gradually enlarge. After about the twelfth week their edges touch, and they remain closed as in sleep until birth. The lachrymal puncta, and generally all the lachrymal apparatus, as also the Meibomian glands, are proportionally more developed during the early periods of life than subsequently. The eye is proportionally larger in the early periods of life than afterward. The two external membranes, the sclerotica, especially its posterior part, and the transparent cornea, are proportionally thicker. This character belongs especially to the cornea, which is twice as thick as it is in the adult, from a considerable quantity of reddish serum existing between its layers, in the full grown fetus, so that its anterior face is nearly plane, and the posterior touches the iris. It is also less transparent than subsequently. In old age it becomes planer, harder, denser, and more solid : we also see developed, in old men, a nebulum, which extends from the edge to the centre ( geronlonoxon , s, arcus senilis), which undoubtedly depends on the slowness with which the substance is renewed, whence the fluids have more tendency to coagulate ; this resembles those ossifications which supervene in old age in other parts of the body. pigment which covers.it has a deeper tint. The pigment begins to appear very early at- the fifth month of pregnancy. But before birth it is less colored than in the adult : it adheres less to the choroid membrane and the iris : it does not exist on the outer face of the first of these two membranes, so that the intensity of its color and even its quantity seems to depend on the action of the light. In subjects al an advanced age, its color changes like the hair, and it is lighter, but the cornea and crystaline lens loose their transparency in the same proportion. The deeper color of the pigment in youth, depends partly on the fact, that the globules are nearer each other, partly also on their being blacker at this period. They are also softer in young people, and hence they lose their form, and are detached from each other by drying. In the full grown fetus, the white cellular tissue existing between the vessels of the choroid membrane, contains no iron, while there is much in that , colored black found in the same place in the adult. (1) The iris is one of the parts of the ej'e which varies the most at different periods ; the greatest change is the closing of the pupil by the pupillary membrane ( membrana pvpillaris ), or the membrane of Wachendorff, in honor of its discoverer. (2) The external edge of this membrane arises from the inner edge of the iris. It fills the whole pupil, so as to separate completely the posterior from the anterior chamber. It is a very tense, rather solid, but very delicate, thin, and transparent membrane, so that when its bloodvessels are injected, they cannot be perceived until the eye is hardened by immersion in alcohol. It is composed of two layers, the anterior of which is a continuation of the serous membrane which lines the anterior face of the iris ; and the posterior is very vascular, and is continuous -with the posterior face of the his. We have never known it to be covered posteriorly with a fibrous mucus, as Haller and Wachendorff assert. Some of its arteries arise : 1st. From those which form the inner circle of the iris : they radiate from this circle towards the centre of the pupillary membrane, where anastomosing with the adjacent vessels, and not with those opposite, they terminate and leave a small space in the centre of the membrane. They also anastomose with each other frequently in their course. anastomose with the preceding. 3d. Others still smaller arise from the vessels of the anterior face and from the greater edge of the crystaline lens, and are distributed principally on the posterior face of the pupillary membrane. (2) E. J. Wachendorff, in Comm. J\or., 1740. Hebd. 18. p. 137. — Haller, De nova tunica pupillam fœtus clauder.ti ; in the Act. Upsdl., 1742, and Op. min., vol. i. p. 329.— J. G. Rœderer, Defœtu perfecta , Strasburg-, 1750, § xxvi.— B. S. Albinus, De membrana pupillam Inf antis nuper natiprœcludente : in Anrot., acad. 1. i. cap. vii. — Vicq-d’Azyr, Sur la membrane pupillaire du fœtus : in Hist, de la soc. roy. de méd., ann. 1777 and 1778, p. 257. — J. F. Blumenbach, De oçulis leucœthiopum et motu iridis, Gottingen, 1786. — H. A. Wrisberg, De membrana fœtus pupillari: in Non. comm. Gott., vol. ii. and in Syllog. comm. I. — Edwards, Sur la structure de l'œil .- in the Bull, delà soc. philomatique, 1814, p. 21. — J. Cloquet, Mémoire sur la membrane pupillaire et sur la formation du petit cercle artériel de Viris, Paris, 1818.— Portai, Sur la membrane pupillaire : in Mémoires du Museum, vol; iv. p. 457. face of the pupillary membrane. The pupillary membrane passes through several periods of development. Its primitive form is not known, nor the manner in which it is produced, nor the period of its first appearance. According to Wrisberg it is not perceived distinctly before the third month of pregnancy. It is gelatinous and destitute of vessels until the fifth month, but at this period it becomes • firmer and vessels are developed in it. Perhaps, however, in the early periods of life it is greater in proportion to the rest of the iris, for the development of the latter membrane begins at its external edge. It is most evident at the seventh month of pregnancy. It begins to disappear at the eighth month from the centre to the edge, that is, from the portion which has no vessels. In the full-grown fetus the only vestiges of this membrane are some small loose flocculæ attached to the edge of the pupil. It generalty disappears much sooner in animals bom with the faculty of seeing than in those born blind ; it continues in these latter also as long as the eyelids remain closed.(l) The vessels are not destroyed with it. They contract from the centre toward the circumference ; their arches diminish, and they are finally adapted to the inner edge of the ins, where they form the small arterial circle, which does not exist so long as the pupillary membrane continues. (2) Although this membrane perfectly separates the two chambers, each cavity constantly incloses an aqueous humor, which does not exist in the posterior alone as Edwards(3) and Ribes(4) assert. We have demonstrated this perfectly, (5) and Cloquet after us. (6) A very curious periodical difference of the iris is a want of continuity of its circle, which is observed during the early periods of pregnancy, and which is very sensible at its inner part until about the seventh week. The retina is much thicker in the early periods of life than afterward. This thickness does not depend on the greater development of its inner layer ; and so far from the medullary layer being proportionally thinner at this period, so far from possessing at that time less medullary matter, as has been assorted, (7) this substance on the contrary is more abundant, and hence the increase of thickness presented (2) . In demonstrating- this fact J. Cloquet has verified a conjecture of Blumenbach : E jusque (memijranœ puvillaris) vasorum elliplici arcus scnsim scnsimquc reirahuntur, tuneque, ni graviter fall.or, annulum iridis inlcriorcm cjjiciunt, cujus ccrte ante eum terminum nullum in Jcetuum oculis vestigium reperire potui. (Inst, physiol., 1787, p. 208.) also more firm and resisting. We already perceive its fold in the sixth month of pregnancy, and even in the full-grown fetus it is greater than in the adult. The thin place is visible, but the yellow tint does not appear till some time after birth. It gradually becomes more intense, but turns paler as age advances. It would seem that the fold diminished regularly and finally disappeared entirely. The less marked development in this region in old men is about in a direct ratio with the loss of transparency which gradually takes place in the cornea. The aqueous humor is turbid in the fetus. It becomes perfectly transparent during the first few weeks after birth. The crystaline lens also is much more convex in the fetus and in infancy than in the adult. At first it projects through the pupil, and thus pushes the iris before it, so that it is separated from the transparent cornea only by this membrane, being situated in its special groove. In this respect and in the absence of the eyelids, the eye of the fetus resembles that of fishes. This arrangement, added to the great thickness of the transparent cornea, causes the chambers to be smaller and the aqueous humor less abundant than in the adult. All the humors, however, excepting the aqueous, are more abundant in youth than subsequently, whence it follows that the whole eye, and particularly the cornea, projects more, while as age advances, the eye slightly collapses and the transparent cornea particularly flattens. As age advances the crystaline lens assumes more consistence, and also becomes yellowish on tearing the centre, so that this tint is found generally in persons in advanced life. The same is true of the humor of Morgagni. At the same time this humor and that which fills the two chambers are slightly turbid, which is sometimes the case also with the vitreous humor. EYE IN THE ABNORMAL STATE. § 2020. The situation of the eye exposing it to the action of all external causes of injury, and its extreme sensibility rendering it liable to be diseased from the influence of these causes, or to participate in the affections of other parts of the body, and finally its very complex structure, singularly multiply the number of the anomalies it may present ; these anomalies are more easily perceived even during life than in I. DEVIATIONS OF FORMATION. § 2021. Here, as in other organs of the body, the primitive deviations of formation are the most remarkable in respect to the consequences deduced from them in regard to the general theory of organization. may mention : a. The absence of the eye or of some of its parts. Here, as in the other organs, the conditions are not always exactly the same. In one case observed by Malacarne,(2) the optic beds and nerves, the common and the superior motor nerves, the globe of the eye, its muscles, the caruncula lachrymalis, and the optic foramina, were all deficient. The globe of the eye was replaced by a hard mass. The lachrymal apparatus and the eyelids were perfectly developed. In another case(3) the globe of the eye and the optic nerve as far as its bed and the optic foramen were deficient, but the accessory nerves and the lachrymal gland were present. b. Smallness of the organ. (1) Beside the treatises on the diseases of the eyes, among' which we may mention particularly those of Maître Jean, Taylor, Janin, Rowley, Beer, Scarpa, Schmidt, and Himly, beside also the works already mentioned, because their authors have examined it both in the state of health and that of disease, we shall mention, on the pathological anatomy of this organ, the following: J. C. Sybel, Diss. de quibusdam materiœ et formas oculi aberrationibus a statu normali , Halle, 1798. — J. Wardrop, Essays on the morbid anatomy of the human eye , London, 1818. — Farre, A treatise on some 'practical points relating to the diseases of the eye , by the late Conningham Saunders, to which are added , &c., London, 1816. — Demours, Traité des maladies des yeux, Paris, 1818. — Helling, Praktisches Handbuch der Augenkrankheiten, Berlin, 1721. — Baratta, Osservazioni pratiche suite principali malatti e degli occhi , Milan, 1821. — L. M. Mejra, Tratado tcorico y practico sobre las infermidades de los ojos, Orea, 1820. — B. Travers, Synopsis of the diseases of the eye, London, 1820. — J. Vetch, A practical treatise on the diseases of the eye, London, 1820. — Consult also, on the pathological anatomy of the lachrymal organ, J. A. — C. H. Tode, Des maladies de la glpnde lacrymale ; in the Mélanges de chirurgie étrangère, Geneva, 1824, p. 391. d. The adhesion of the two eyes. It is rather a general law in this case that the eye formed by the fusion of the two in one is situated directly on the median line, and is symmetrical in its structure. have never been observed. II. The deviations of formation in respect to quality are also rare. They affect most frequently the form of the iris and that of the pupil, which then is usually less round and most commonly perpendicular, rarely horizontal. This anomaly, often peculiar to certain families, and hereditary, is always curious as an analogy with animals. (2) The iris is rarely enlarged so much outward that the pupil does not correspond to the axis of the eye, being carried much more inward. (3) The transparent cornea is sometimes conical ( staplujloma conoides ), and at the same time it is more or less thin. This state is its greatest degree of convexity, whence this includes also the greatest degree of myopia. § 2023. The accidental deviations of formation are more common than the preceding and very various, but they depend most generally on a previous alteration in the chemical composition, and the texture of the parts is then more or less changed. The principal deviations of this kind are : 1st. Absence. Here we may mention the loss of the eyelashes and eyebrows, caused by the destruction of their bulbs, by inflammations and ulcerations of the eyelids. parts, particularly the optic nerve and the retina, are often wasted. We have found several times in subjects who have been blind for a long time, that the retina was unusually thin and destitute of medullary substance in séveral parts of its extent, this substance existing at intervals. When the power of vision is more or less diminished, the yellow spot also returns to the degree of color it presented before the eye was exposed to the light, for in this case its tint is more or less enfeebled. At tho samo time the fold is more ov less effaced.(l) Sometimes in subjects affected with amaurosis the retina presents in this place black spots ;(2) but only the diseased eye undergoes this change ; the fold and the spot are on the contrary sometimes more sensible in that of the -healthy side ;(3) the optic nerve is even sometimes larger than in the normal state. (4) eases of long duration and excessive evacuations. The crystaline lens, left in the eye after separating it from its capsule partially or wholly, disappears very rapidly. At the end of a few years there is hardly a piece as large as a pin-head.(5) b. Enlargement. The eye sometimes enlarges so mttch from dropsy ( hydrophtlialmus ), that it projects on the outside of the orbit. This dropsy is situated primitively in the vitreous body ; but it extends to every part, so that in some subjects we find considerable serum between the ciystaline lens and the vitreous body. (6) Scarpa states that dropsy of the posterior part of the eye is usually attended with an increased secretion out of the vitreous body, as we have found several times on the inside of the choroid membrane and of the retina a great quantity of limpid serum, in which is a cord directed from before backward, formed by the morbid alteration of the vitreous body and retina.(7) In this case probably the serum came from the serous membrane discovered, by Jacob. A partial enlargement of the eye, often met with, forms staphyloma,(8) a greater or less thickening of the transparent cornea, which causes the falling of this membrane, attended with its opacity, and depends on a previous inflammation situated in it. In this case the cornea generally adheres to the iris. The increase with the thinness of the sclerotica, which is much rarer and is also termed staphyloma , appears under the form of bluish elevations, the color of which depends on the varicose state of the vessels of the choroid membrane. It supervenes principally on the circumference of the transparent cornea after arthritic ophthalmia, but is observed more rarely at the posterior part of the sclerotica.(9) results from inflammation. When the conjunctiva has been violently inflamed and neglected, the eyelids join either to the anterior face of the eye ( symblepharon ), or with each other ( ancyloblepharon ). Sometimes these two kinds of adhesion take place simultaneously. The parts fused are sometimes nearer each other, and are often united by a greater or less number of accidental membranes which vary in length. Sometimes they adhere at birth. After inflammations of the iris, the pupil adheres ( synizesis ), or the anterior face of the iris imites to the posterior face of the transparent cornea, or finally the posterior to the anterior face of the crystaline capsule (synechia), by an effusion of albumen which coagulates, and which is sometimes distinct from the other parts in the form of a membrane. The obliteration of the ducts of the lachrymal gland is caused by external lesions on the outside of the .eye. It depends on inflammation and ulceration, like the contractions of the excretory channels of the lachrymal humor. of albumen into its substance. b. Abnormal separation. The parts of the eye rarely present this anomaly except from external injuries. We however must arrange here the detachment of the crystaline lens observed after violent cephalagia and the fall of this lens into the anterior chamber across the pupil, which results from the percussion or commotion of the eye.(l) Ulcers produce especially in the transparent cornea, sometimes also in the iris, solutions of continuity, which, when situated in the first of these two membranes, cause the effusion of the aqueous humor and the falling of the iris. The iris is frequently detached in a greater or less extent from the sclerotica by a powerful shock : two pupils might then be said to exist. We must refer also to this head the abnormal enlargement of the openings, for instance, the pupil (mydriasis). Ruptures and other lesions of one or more excretory passages of the lachrymal gland form the lachrymal tumor (dacryops), the accumulation of tears between the conjunctiva and the globe of the eye, or a too great effusion of this fluid. lachrymalis. 4th. Deviations in situation. These anomalies extend to the whole eye, or affect some of its constituent parts only. The globe of the eye may be pushed out of the orbit by tumors in its cavity ( exophthalmia'), and may fall forward from the injury or the paralysis of its of the eyelids, and causes them to turn over outward. The direction of the eyelids alone is frequently changed, which may take place in two different modes, according as they are turned outward ( ectropium ) or inward ( entropium ). The latter effect is produced particularly by the destruction of the internal layer of the skin of the lid and the cartilage, after inflammation of the eyelids, by a dropsical state of these parts, sometimes by the paralysis of the levator palpebræ muscle. This paralysis however is never sufficient to cause it alone, it producing only the fall of the upper eyelid ( blepharoplosis ). The first state is caused principally by wounds in the skin with loss of substance, sometimes also by the development of tumors and ex crcscences on its inner face. When the fid is turned inward, the eyelashes naturally ’touch the globe of the eye. Hence it is called trichiasis , in which only some lashes participate, which occurs after inflammations of the eyelids, and arises from the inner part of the edge of the eyelids being destroyed by ulcerations. The prolapsus of the iris occurs in wounds of the transparent cornea, and when this latter membrane presents several openings through which the iiis protrudes, a kind of staphyloma occurs which is termed the hunch of grapes. At first the protruded portion of the iris is exposed, soft, thin, and very vascular ; it gradually becomes solid, the circulation stops, and it is covered by a thin, grayish white membrane, which Beer regards as the regenerated conjunctiva ;(1) but it is more correct to consider it a new production formed by the exudation of the lymph from the iris. II. ALTERATIONS IN COMPOSITION AND TEXTURE. § 2024. Almost all the alterations of composition and texture in the eye, as in other parts of the body, depend on inflammation, to which this organ is very much exposed. Several of them however are developed, and we cannot consider them as resulting exactly from previous inflammation. Alterations in texture are very rarely congenital. We must, however, regard as such the anomalies in the color of the eye, which may be referred ; 1st, to a want of color in the pigment ( léucœthiopia ) ; 2d, to the different colors of the iris in the two eyes, or even in its different parts in the same eye ; 3d, to a want of transparency. Farar also(l) has observed, in three children of the -same family, that the cornea at the moment of birth was clouded by a nebulosity, which afterwards gradually disappeared from the outside towards the centre. 1st. In the eyelids. a. Grando , a rounded tumor, which varies in hardness and is developed on or a little below the lower edge. It is a purulent cyst, a stye ( hordeolum ), not entirely destroyed by suppuration, and which is filled with coagulated albumen. cula lachrymahs and the third eyelid. 2d. In the conjunctiva. The film is a greater or less elevation which is developed between the anterior face of the sclerotica and the conjunctiva which covers it. The pterygium( 2) commonly arises in the inner angle of the eye, where it extends outward to the anterior face of the transparent cornea, and beyond the centre of this latter. We rarely find a second or even a third in the external angle of the eye or in another region. It is more or less vascular, and its base always looks toward the circumference and its summit towards the centre of the eye, undoubtedly because the connection of the conjunctiva with the subjacent membrane is less intimate in the first place than in the second, where in fact it blends with the transparent cornea. The pannus differs from the pterygium as it is the substance of the conjunctiva, and sometimes also that of the transparent cornea, which thickens. The tumor termed pinguecula is generally developed in the external angle of the eye, or at least on the outside of the cornea. It is seldom larger than a bean, and it is formed by the conjunctiva and the subjacent cellular tissue. 3d. In the transparent cornea( 3) the principal results of inflammation are maculae and nebulae, ( obscuratio , albugo, s. leucoma ), which sometimes arise only from simple exsudations in the tissue of the cornea, sometimes also are cicatrices of ulcers of this membrane, and vary in their extent and their degree of opacity. In the first case, the surface of the cornea does not differ at the spot where the point is, from (2) Beer ( loc . cit., vol. ii., p. 638) does not consider the pterygium as resulting' from an inflammation. We may however mention in support of this not only his own opinion that the tumor usually appears when caustics are applied (p. 640), but also Larrey’s observations, who remarked that it frequently was a consequent of the Egyptian ophthalmia. other parts ; in the second it is deep. The cicatrix is always hard, like the spot produced by an old exsudation. Farther we observe no other alteration of texture in the place where it is situated.(l) 4th. In the iris the pupil is effaced ( atresia pupilloe) by an opaque false membrane, which causes at the same time the adhesion of the posterior face of the iris to the crystaline ( synechia ) capsule. Then the production of pus or of a puriform fluid on the surface of the iris, whence a puriform congestion is formed in the chamber of the eye, which is termed hypopon. Scarpa thinks that it is real pus which forms here, since we do not find in the iris an abscess the rupture of which could produce this purulent humor. (2) The serous nature of the two faces of the iris favors his opinion, but the authority of Beer(3) at least authorizes us to doubt it as a general rule. 5th. In the crystaline lens and ils capsule , which are frequently the seat of cataract ( calaracla , s. sußusio), which most generally renders opaque, parts normally transparent. Cataract varies in situation, consistence, and color. It usually arises from opacity of the crystaline lens (C. crislallina, C. lenticularis), more rarely of the crystaline capsule, especially of its posterior face ( C. capsulaire, C. capsularis), still more rarely in the humor of Morgagni (C, laiteuse, C. JVlorgagniana, s. lactea). These three kinds coexist in the capsulo -cry si aline cataract (C. capsulo-lenticularis) . Opacity generally commences in the ccntre(4) and very deeply in the crystaline cataract, and on the contrary in the margin in the capsular cataract. Sometimes in the latter case only some parts are opaque, forming the doited or mottled cataract (C. feneslrata). Most generally, but not always in old men, the crystaline lens is unusually hard, and in a measure ossified or petrified (C. dura). It is rarely softer than in the normal state (C. mollis), or even fluid (C. fluida), The capsule is more frequently hardened and thickened. Its anterior face is also covered in some cases (C. trabiculata, pyramidala) by a layer of substance, sometimes having the consistence of osseous tissue,(5) which arises from an exsudation formed by the inflamed iris, and which consequently can always be separated to a certain extent from the capsule. (6) The color of the cataract is most generally grayish white. In the crystaline and the capsular cataract, the crystaline lens and its capsule are not unfrequently detached from each other, or from the adjacent parts, by a shock of the body. But they are sometimes connected more intimately, and so extensively that the crystaline capsule and the iris adhere. (4) Rudolphi ( Grundriss der Physiologic, vol. ii., p. 184) mentions a family in Berlin in which the central cataract [C. cenf rajas) is hereditary; this consists in a eingle dark point in the centre of the crystaline lens, which remains stationary In the pyramidal cataract the thick anterior wall of the capsule sometimes projects through the pupil and advances to the transparent cornea, to which it sometimes adheres. § 2025. The new formations developed in the eye are probablycaused by an action similar to inflammation ; we cannot, however, always consider them as resulting positively from this cause. They are divided as in every other part, into those which are abnormal only from the place where they are developed, and those which are entirely new. we distinguish : a. The cellular tissue, which, assuming the form of false membranes, unites parts which are primitively separate, and which we have already mentioned in this respect as produced by inflammation. ferent new formations, especially in the preceding. c. The serous tissue, which is developed in the eyelids, especially the superior, in the form of cysts within the lachrymal gland in the orbit, (2) more rarely between the choroid coat and the retina. (3) We probably can arrange here the cysts formed on the surface of the iris when this membrane projects through an opening in the transparent cornea: cl. The fibrous tissue, which occurs much more rarely. In one case the retina was changed into a white, fibrous, and very solid membrane, exactly similar to an aponeurosis, the external face of which adhered very intimately to an osseous layer between it and the choroid membrane. (4) e. The osseous tissue, which generally appears in the form of more or less irregular thin layers between the choroid coat and the retina, probably from the change of the serous membrane which covers the outer part of the choroid coat. It is seen more rarely in the transparent cornea, (5) and it is probably developed primitively in the membrane of Descemet. We must probably mention here the considerable and petrous hardening of the opaque crystaline lens and the formation of stony concretions in the place of the vitreous body ; for the latter concretions, even when they become considerably thick, do not result from the change of the vitreous body, but from between the choroid membrane and the f Among1 2 3 4 5 6 the constituent parts of the cutaneous tissue the hairs are probably the only ones abnormally developed in the eye, uhless we refer to it those cysts which form around hernias of the iris, and which we have referred to the serous system. The conjunctiva seems to be the only part of the eye where the hairs take root. They sometimes appear also as abnormal eyelashes ( distichiasis ) on the inner edge of the upper eyelid after neglected ophthalmias, and differ from the common lashes in their situation, thinness, smallness, and whitish eolor.(2) They are rarely developed in the conjunctiva of the eye, where they appear either in the conjunctiva itself, which is most usual, (3) or on the transparent cornea. (4) In the cases observed by Himly they were inserted in the centre of a fatty production, and in all other cases, at least those detailed by Wardrop, and Demours, a pterygium or film was the base of them, that is, they were preceded by a morbid change. Himly and Wardrop have observed this formation in the external, and Demours in the internal angle of the eye. This latter case consequently resembles the considerable increase of one of the hairs of the caruncula lachrymalis, seen by Albinus.(5) It is curious that in the few cases of this anomaly as yet published, there is an evident connection between the period of puberty and the development of accidental hairs. In the cases described by Wardrop, the hairs did not appear till the age of sixteen years with the beard, and in that described by Himly the tumor appeared at the age of two years, but did not become troublesome till the age of twenty, doubtless because hairs were not developed upon its surface. inflammation. b. Fungus hematodes, which is developed sometimes in the eye itself, and as it would seem on the posterior part of the choroid membrane, whence it goes forward, destroying before it all parts of the organ, and often extends to the outside of the eye in the fat of the orbit. Perhaps we ought also to arrange here the excrescences which are developed within the optic nerve. (6) c. The entozoaries. To these may probably be referred, at least sometimes, the loose hydatids which appear in the lachrymal gland, and which are explained better in this manner than by attributing ORGAN OF SMELL. § 2026. The senses of hearing and sight, the organs of which have been described, differ from the others in respect to their relations with other organs, as they are more independent. Those of smell and taste, on the contrary, are only portions of other organs, for they both belong to the digestive system, and the first also to the respiratory system. It would then be proper to consider the organs of smell, voice, and respiration, of taste, and of digestion, as forming a single system. It is impossible to separate the history of the tongue from that of the intestinal canal, since it is situated in a cavity, the commencement of the digestive apparatus, and in which the food is remarkably changed, since it is also situated behind the organs which cause these changes. But we shall consider the organ of smell separately, since it is more independent than that of taste, and after leaving the fishes it is entirely separated from the respiratory system, which in the three upper classes of animals communicates with the exterior, not only by the olfactory organ, but also by the oral cavity. 1st. Of a bony cavity divided into several compartments, the upper and posterior part of which is more extensive, and is formed by bones, whence it is termed the bony nose ( nasus osseus ), and has already been described in osteology. Ziervogel (Aurivillius), De naribus internis, Upsal, 1760.— A. Scarpa, Anatomicæ disquisilioncs de audita et olfactu, Milan, 1795.— T. C. Rosenthal, De organo olt actus quor undem animalium, Gripswald, 1807. — S. T. Scemmerring“, Abbildungen des menschlichen Organs des Geruchs, Frankfurt, 1809. I. CARTILAGINOUS NOSE. § 2028. The cartilaginous nose, the anterior extremity of the bony nose, is composed of a central and perpendicular portion, the cartilaginous septum of the nose ( septum narium cartilagineum), of two alee. ( pinnae , s. alee nasi), finally of two oblong openings termed nostrils (jiares), by which the cavity of the nose opens externally, and which are supplied, especially on their inside, with stiff hairs ( vibrissa: .) It is composed of several thin cartilages united with each other and with the bony portion of the nose, externally with the skin, internally with a mucous membrane. There are generally eleven. The largest, the cartilage of the septum , is perpendicular and square. It completes the osseous septum anteriorly, where if is included between the perpendicular plate of the ethmoid bone, the vomer, and the median suture of the two proper nasal bones. Its anterior edge descends from before backward, is loose, and is attached to a long prolongation of the skin, the cutaneous septum of the nose. The superior lateral cartilage is square and is attached to the lower edge of the proper nasal bone, to the ascending process of the superior maxillary bone, and to the upper edge of the preceding. It is generally blended with this latter so intimately that they form but one body.(l) Below this superior lateral cartilage, and at the side of the lower part of the median line, is the inferior lateral cartilage, or the cartilage of the ala ( C . pinna ;), which is very low. This cartilage is' narrow and formed of two pieces, an internal and an external, which unite forward at an acute angle, where they frequently present a foramen, and are sometimes entirely separated from each other. The external piece is longer and higher than the internal. Next come from before backward and from without inward several square cartilages ; these are much smaller, diminish in extent from before backward, circumscribe the nostril backward and outward, and are often blended with each other and with the preceding. From two to five other still smaller sesamoid cartilages (C. sesamoideœ ) are situated forward on each side, between that of the septum and the two lateral cartilages. A. LEVATOR ALS NASI LABIIQUE SUPERIORIS. § 2030. The levator alee, nasi labiique svperioris or the pyramidal muscle, grand sus-maxillo-labial, Ch., arises from the nasal process of the upper maxillary bone, usually blends in this place with the frontalis muscle, descends in the side of the nose, and divides into two fasciculi, an anterior which is smaller, and is expanded in the lower lateral cartilage ; the other is much larger, and blends with the orbicularis oris and the superior muscles of the upper lip. It raises the ala of the nose and the upper lip, and opens the nostril. B. COMPRESSOR NARIUM. § 2031. The compressor narium muscle, sus-maxillo-nasal , Ch., is triangular, thick, and narrow at the base, and broad above. It ascends from the posterior part of the ala of the nose, where it is blended with the preceding, which partly covers it, and goes from behind forward toward the back of the nose, on which it unites with that of the opposite side without any intermediate tendon. It often gives off at the upper part, a prolongation which blends with the frontalis muscle. This is the procerus muscle of Santorini, the lower part of his Iransversus nasi muscle. § 2032. The depressor alee nasi muscle, the proper muscle of the ala ( JMT. pinnarum, s. narium lateralis , Santorini, s. dilator narium proprius , s. inferior ), arises from the upper maxillary bone above the c.anine tooth and the external incisor. It is formed of oblique fibres, and extends almost the whole length of the outside of the cartilage of the ala of the nose. Its principal effect is to dilate the nostril when the nose is at rest. Being inserted in the upper maxillary bone, it can depress the nose. Finally, as its external face is attached to the integuments of the upper lip, it can also depress this latter; (1) Santorini, Obs. anat., cap. i., de musculis faciei, p. 11. — Id., Tabulas XVII., tab. i. — A. F. Walter, Tenor, muse. hum. corp. anat. repet., Leipsic, 17-31. — Isenflannn has described and figured them in his Praktische Anmerkungen über die Muskeln, Erlangen, 1778, p. 345. We sometimes find before it a proper, but much smaller muscle, to dilate the nostril ; it is called the myrtiform muscle of Santorini , and sometimes surrounds the nose like a sphincter. § 2033. The depressor narium muscle forms on each side a small fasciculus situated along the median line : it arises from the inner upper part of the orbicularis oris muscle, and is attached backward and inward to the inner branch of the cartilage of the ala of the nose. It draws the cartilaginous nose downward and backward, and also contracts the nostrils. III. MUCOUS MEMBRANE, § 2034. The mucous, olfactory, pituitary, or Schneiderian membrane of the nose, has not the same nature in all parts. The proper nasal portion is more than a line thick in some places ; it is thick, very red, and intimately fitted to the bones which it covers in every part ; it contains numerous depressions and mucous follicles, and also at the lower and inner part of the nose, some small yellowish and distinct glands, which are imbedded in its peculiar tissue. At the anterior and inferior part of the nose it is thinner, harder, drier, and also provided with mucous follicles. If we except this latter portion, the pituitary membrane is covered in every part with very short villosities. At the lower edge of the septum there is not unfrequently a narrow canal, the direction of which is from behind forward, terminating posteriorly in a cul-de-sac, and which opens at some distance behind the anterior edge, evidently above the organ of Jacobson.(l) The mucous membrane of the accessory cavities or of the sinuses, is externally thin, smooth, and yellowish white. It adheres but slightly to the surface of the bony cavities it covers, undoubtedly because numerous vessels and nerves do not enter it, through the substance of the bones. (3) Magendie has doubted the proposition generally admitted in a memoir, entitled “ Le nerf olfactif est-il l’organe de l’odorat ? In the Journ. de phys. expér., vol. iv. p. 169.” Mery already doubted that the olfactory nerve was the organ of smell, and asserted that it was supplied by the fifth pair. (Brunet, Progrès de la From the lower face of the prominence which terminates it, two series of filaments arise, an external and an internal, which correspond to the two series of foramina in the cribriform plate of the ethmoid bone, although two or three of them frequently emerge through the same foramen. They vary much in number and size. There are from four to twelve. The anterior go downward and forward, the middle directly downward, the posterior downward and backward. Shortly after leaving the olfactory nerve they enter the sheaths of the duramater, within which the posterior, particularly, pass a long distance before entering the foramina of the cribriform plate. They are covered first by the dura-mater, and flattened by the arachnoid membrane, which is less compact, and does not attend them as far. Entirely on the outside, each is surrounded by a tunnel-like prolongation of the dura-mater, which extends very far, and makes them apparently larger than they are on leaving the ganglion. They anastomose below the cribriform plate, descend between the bones and the pituitary membrane, soon ramify very much, and thus gradually approach the loose surface of the membrane. They descend side by side, forming a single layer. The external series is distributed in the sides of the nose, particularly in the two superior turbinated bones, forms considerable anastomoses, but the filaments formed by these nerves are much less compact than those of the external : they do not enter into the ethmoid cellules, and do not go to the mucous membrane of the inferior turbinated bones, or at least send forward but few and very minute minuscules. the sinuses. médecine, 1697.) Having opened the skulls of three or four men, in whom the organ of smell during life was unaltered, he found the pair of nerves callous near the cerebrum. Loder, however, (Observatio tumoris scirrhosi in basi cranii reperti, Jena, 1779,) has seen the olfactory nerve destroyed in a man destitute of the power of perception, and Oppcrt also has observed the same thing in a female, in whom the sense of smelling was deficient (Diss. de vitiis nervorum organicis, Berlin, 1815, p. 16). Cerutti ( Beschreibung der pathologischen Präparate des anatomischen 7 'heaters zu Leipzig, 1819, p. 208) mentions the cerebrum of a • îan who never possessed the faculty of smelling, in whom the olfactory nerve and its groove on the lower face of the inferior lobe were deficient. Rosenmuller even has described this case (De defcclu nervi olfac., Leipsic, 1817). But Rudolphi regrets, and with justice, that the turbinated bones of the septum were not examined, since in many cases, when it has been said to be deficient, it has been found, but very soft and diffluent. Farther, the facts related by Magendie, seem to give some weight to the old opinion of Mery ; at least they should draw the attention of physiologists to the sinuses of the nasal fossæ, to which Malacarne, Weinhold, Blumenbach, and Treviranus, have attributed very different uses, which are sometimes very trivial, as those mentioned by Weinhold. It would be important to prove, whether, as Deschamps and Richerand assert from experiments made on subjects affected with diseases of these cavities, they are unconnected with the olfactory function; but of this we may doubt until we have more information, especially since the fine researches of Treviranus on the fifth pair of nerves. F, T. Among the nerves of the fifth pair or the accessory nerves of the nose, the superior nasal nerves go backward, the middle and the inferior nasal nerves, and the nerve of the septum which arise from the pterygo-palatine nerve, and the ethmoid nerve which comes from the nasal branch, go farthest forward, for they extend even before the olfactory nerve, and are distributed in the mucous membrane of the nose. These nerves also surround the surface in which the olfactory nerve is distributed, and anastomose with its posterior and external filaments. Those from the second branch of the fifth pair communicate also with the ethmoid nerve. Hence, the accessory nerves form a complete circle around the expansion of the olfactory nerve, like that formed by the ciliary nerves around the retina. Although they proceed much farther, they however occupy much less space than the twigs of the olfactory nerve. § 2036. The impressions of the odors are received by the olfactory nerve, and directly by the pituitary membrane. The portion of this latter in which the olfactory nerve is distributed, seems to be the principal seat of the faculty of perceiving them, although the membrane which lines the sinuses, partially contributes. periodical differences in the bony nose. The whole organ long continues very imperfect. There is no trace of the external nose until the seventh or eighth week of pregnancy. At this time the nostrils appear, separated by a proportionally very broad septum, as two very small openings ; little later the nose begins to project over the mouth ; but during pregnancy it is blunt, and proportionally very small ; a large nose in an infant is very unpleasant, because it is a character foreign to the early periods of life. appear till towards the end of the third month. Until the end of the second, the nasal cavity communicates with that of the mouth. It is at first very narrow from above downward, and from right to left, on account of the greater breadth of the septum. 6th. The more or less evident want of symmetry arising from an obliquity in the septum, which is sometimes so great that this latter even touches the wall towards which it inclines. Most of these primitive deviations of formation are developed also consecutively during life, after the bony and musculo-membranous parts of the nose and palate are destroyed by syphilis. The most frequent abnormal formations are the polypi of the pituitary membrane. Hydatids are infinitely more rare. They sometimes become so large that they considerably contract the nasal cavity.(3) Their deviations of formation consist in their absence and narrowness, which are usually congenital. Sometimes these sinuses do not communicate with the nasal fossæ : but this anomaly almost always occurs, consecutively, after inflammation. (5) (4) L. H. Runge, De morbis prœcipuis sinuum assis frontis et maxilice superior is, Rinteln, 1750. — Bordenave, Sur les maladies du sinus maxillaire ; in the Mem. de Vac. de chir., vol. iv. p. 329. — C. A. — F. D. Wagner, Diss. de po'lypis nariumet antri maxillaris, Berlin, 1821. moist as usual. A greater or less quantity of liquid, however, often collects within them, from the effect of certain causes ; this more or less forcibly distends them, their parietes' become thinner, and are finally destroyed when the compression continues a long time, although this state does not deserve the name of dropsy of the maxillary sinus, because the effused liquid is not of the same nature as that exhaled by serous membranes. ( 1) Entirely new formations, as fibro-cartilages and polypi, either alone or united, are not unfrequently developed in the accessory cavities of the nose. These formations are particularly common in the maxillary sinus, which is the most subject to morbid alterations, doubtless on account of the nearness of the teeth, and because the situation of its opening renders the escape of its secreted fluids more difficult. We may, however, blend them with the analogous tumors which are developed out of the antrum Highmorianum, in the zygomatic fossa. (2) OF THE VISCERA OR FORMATIVE ORGANS. § 2040. The viscera, { 3) which may also be called the formative organs, because their essential function is to form new substances, present several general characters, the principal of which are as follow : 1st. They are situated principally in the trunk, and occupy only a small part, of the lower region of the face, and are generally placed in cavities formed by bones, muscles, and serous membranes, which vary much in capacity. An aqueous vapor is effused between them and the parietes of these cavities. 2d. They are entirely, or at least in great part, and in their most important portions, enveloped by serous membranes. Each system is separated in this manner from the others, and each occupies a distinct section of the trunk. 3d. They receive most of their nerves from the ganglionnary system, and their nerves are always proportionally larger than those that go to the organs of sense, excepting always certain parts, as the tongue and the external organs of generation, which being abundantly supplied with nerves, possess a very acute and special sensibility, and are OF THE VISCERA. in fact, real organs of sense. Most of the viscera receive their nerves from the ganglionnary system, and next from the pneumogastric nerve ; but the hypoglossal, the glosso-pharyngeal, and the trifacial nerves, are also distributed in their upper portion, and the inferior spinal nerves in their lower portion. The nerves usually pass some distance before arriving at the organs, and generally each of the latter receives nerves from one pair only. One pair of nerves is distributed in part to several organs. 4th. The course of the nerves in most of their extent is constant. As this condition does not exist in regard to those organs which receive their nerves from the ganglionnary system, we must conclude that it does not depend on the nature of this nerve. It is false that the spiritual principle is not connected with them, and the changes that take place in them are not perceived ; this perception is very manifest in disease, and the sensations that result from them are not more vague or obscure than those ascribed to all the organs except that of sight. _ v 5th. All the viscera are not united, at least in the perfect state, by mucous membranes. The respiratory and digestive systems communicate together in the neck, the urinary and genital systems in the lower part of the trunk ; but the two latter are separated from the digestive system, or at least are connected with it only by the skin. 7th. Their most important part is more or less evidently glandular, All are formed by several glands, the combined action of which is to correct the fluids secreted by them. The necessity of the combined action of several glands is very evident in the most complex system, that of digestion. Next come in this respect the genital organs, especially those of the male. The concurrence of several glands to form a new substance, seems least necessary in the urinary and respiratory systems. A second part is composed of a canal formed of several different superimposed membranes, united by cellular tissue, and with which the gland or glands in general communicate, and which is sometimes open at its two extremities like the alimentary canal, or at one only, like all the others. The nature of the parietes of this canal varies extremely ; they are, however, always formed of at least two superimposed layers, the external of which is condensed cellular tissue, and the internal a mucous membrane. The mucous membrane is covered sometimes in every part, as in the alimentary canal, sometimes here and there by a muscular tunic. 8th. These organs, if we except the genital organs, are, next to the centres of the nervous and circulatory systems, the most necessary for the support of life, although some of their parts may be primitively deficient, or be destroyed in some manner without occasioning severe accidents, and although very considerable alterations do not occasion immediate death, § 2041. The digestive organs comprise an uninterrupted canal open at its two extremities, and several appendages, which, communicate directly or indirectly with different parts of this canal, within which they empty a fluid prepared by them. This passage is termed the alimentary canal or tube ( canalis , s. ductus cibarius). Its upper extremity is the mouth (os), and the lower the amts ; both are situated opposite each other, and nearly on the same line. The canal is imperfectly divided by valvular prominences into several separate portions, which are named according to their form or functions. It is very convenient to admit three parts, which differ in functions, structure, and situation, but which are all repetitions of the same type ; these are the upper, the middle, and the lower portion. The first occupies the head, the neck, and the chest ; the other two, which form most of the digestive system, fill almost entirely the cavity of the abdomen. The upper portion is composed of the oral cavity ( cavmn oris), the pharynx, which is smaller than the mouth, and the esophagus ( gula , oesophagus), which is still narrower, and with which the pharynx is continuous. ■ Directly after passing through the diaphragm the alimentary canal enlarges to form a second pouch, called the stomach ( ventricidus , stomachus), which is the commencement of the middle portion. Next comes a second narrower portion, the small intestine ( intestinum tenue), which is divided, from slight and inessential differences, into the duodenum, the jejunum, and the ileon. The latter is continuous with the terminating portion of the intestinal canal, the large intestine or the colon ( intestinum colon, s. crassum), which is divided according to the situation and direction of its different parts into an ascending, a transverse, and a descending colon. The latter is continuous also with the rectum, which opens at the anus. The small and the large intestines are termed the intestinal canal ( ductus , s. canalis intestinalis) . liver. The salivary glands ( G . salivares) are situated around the cavtiy of the month, into which their secretion goes, and in the abdominal cavity near the upper extremity of the small intestine. They are consequently divided into the oral and the abdominal salivary glands ( G. salivares orales et abdominales). The most internal and the most essential of these layers is the mucous or villous membrane ( tunica mucosa , a. intima , s. cribrosa , s. villosa). It is soft and more or less vascular, incloses numerous small culs-de-sac or small muciparous glands, and its surface is moistened by the mucus which it constantly secretes, and a thinner fluid which is exhaled from it. It is in direct contact with the ingesta. The liquid which it secretes has .a chemical and also a dynamical relation with the ingesta, since its action changes their composition, and they are divided into two parts, one of which, the chyle (cliylus), serves for nutrition, while the other, the fecal matter {faces), being useless, is expelled from the body. The chyle in its turn is so modified that it enters into the absorbing vessels which exist in this tissue. 10th. To their situation and arrangement. We may mention as a general law that the development of the inequalities on the inner face is inversely as that of the muciparous follicles, or still more generally that the prominences are inversely as the depressions ; that the first are more distinct, the more nutrition there is in the contents of the intestinal canal, and that the cavities are more marked, the greater the quantity of fecal matter in the canal. Considered from the commencement of the stomach to the extremity of the intestinal canal, the general character of this membrane is that it is perforated by very , numerous small openings, which are the ori- This membrane is composed in every part by several, at least two, superimposed layers, situated one above the other, and separated only by a very thin layer of mucous tissue. The external layer is generally composed of longitudinal fibres, which are parallel to the axis of the intestinal canal and of the body It is thinner than the internal, and it is extended on the intestine less uniformly. regions of the alimentary canal relate : 1st. To the relation between it and the mind, according as its motions are voluntary or involuntary ; in most of its extent these are involuntary ; they, however, are voluntary at its upper and lower part connected with the adjacent parts by mucous tissue. Besides these three layers there are also two others which are not so generally distributed : one resembles the epidermis, and covers the inner membrane ; the other is given off by the peritoneum, and enve lops the external tunic. The most general character of the glandular appendages of the alimentary canal is, that these parts, except the spleen, are prolongations of the mucous membrane and of the cellular tunic, each of which ramifies like a tree. They differ then from the muciparous glands on the external face of the villous tunic, because they are rather more distinct and are more concentrated in some parts of the alimentary canal. (1) Galoati, Dc tunica Lntestinorum cribrosu; in (lie Comm. Bonon,t vol. i. — Duverney, Œuvres anatomiques, vol. i,, p. 480.— A. Muck cl, > Sur la structure dc la membrane muqueuse des intestins dans l'homme et dans quelques animaux ; in the Journ. compt. des sc, mcd., vol. vii., p. 209. I. PERFECT STATE. § 2045. The oral cavity ( cavum oris ) occupies the lower part of the face. It extends backward to the fauces and forward to the lips, by which it is continuous with the face. It is separated from the nasal fossæ above by the bony palate ( palatum osseum, s. dumm), and backward by the soft palate ( palatum molle, s. velum palati). At its base is the tongue, and on its sides the lower jaw, the zygomatic arch, and the. muscles, some of which are attached to these hones, others to other pieces of bone, and several of which also go to the mouth. As the oral cavity is circumscribed by muscles and by bones which are movably articulated with each other, its form varies, although in general it is rounded and oblong. The alveolar portion of the upper and lower maxillary bones, together with the teeth which are inserted there, divide it into two halves, an anterior, which is smaller, and which may be called the vestibule of the oral cavity, and the posterior, which is larger. The first is included between the alveolar processes and the lips ; the second is situated behind the alveolar arches. These two halves are perfectly separated from each other when the jaws are closed by the two rows of teeth which touch and fit each other from before backward. When perfectly at rest the posterior half contains the tongue and receives the excretory. ducts of the inferior salivary glands, while those of the superior open into the anterior half. The oral cavity is covered on the outside by the common integuments, below which are the bones and muscles, then the buccal membrane {membrana oris), which envelopes every part of it. It lines all the parts which circumscribe the cavity of the mouth, so that it perfectly closes the openings in the bony portion of the palate, the anterior and posterior palatine foramina. Around the alveoli it is uninterruptedly continuous with the membrane which covers them. It forms folds in several places. Four of these folds are situated on the median line. The two most anterior exist between the centre of the anterior faces of the two maxillary bones and the upper and lower lips. They are both termed the frena of the lips ( frenulum labii superioris et inferioris). The upper is much more distinct than the lower, which generally is hardly visible. The third is situated between the posterior face of the lower jaw and the anterior part of the inferior face of the tongue ; it is called the frehum of the tongue ( frenulum lingua). II. DIFFERENCES DEPENDENT ON DEVELOPMENT. § 2046. The form of the oral cavity changes remarkably. In the early periods of life it is proportionally shorter from before backward, especially at its lower part, than when the subject is fully grown. At this time the lips do not exist, so that the oral cavity is uninterruptedly continuous with the face, and its roof, the palate, not being closed, it is blended with the nasal fossæ, toward the upper part of which is the tongue, then proportionally very large. This horizontal septum is gradually developed from before backward by the union on the median line of the palatine portions of the superior maxillary and the palatine bones, and also the soft palate on each side. This union is rarely OF THE DIGESTIVE SYSTEM. perfect before the third month of fetal existence. The soft palate is perfect on the median line even before its two lateral parts are thoroughly united posteriorly, and the uvula descends from their centre between them as an entirely distinct and separate appendage. This soft palate is at first very broad, presents no appearance of an appendage, and is divided in its whole extent into two lateral halves. This division soon disappears, and at the same time the two lateral halves of the soft palate approach each other still nearer, and thus push the uvula a little forward, so that it ‘covers the small fissure still existing in the anterior region of the palate. At this time its upper part is united to the two lateral halves, and the inferior passes downward a little below it, Finally the two halves of the soft palate completely unite with each other and with the uvula, and the formation is completed by the gradual prolongation of the latter. The perfect union of the uvula with the soft palate occurs at the middle or end of the fourth month of pregnancy. The uvula, however, until the end of the fifth month continues to be bifurcated, compared with its state in the adult, although it is united on each side with the soft palate, so that perhaps this period of its development is frequently extended beyond the usual time, although terminated before the end of gestation. § 2047. The most remarkable abnormal state of the cavity of the mouth is when its primitive formation continues, that is, when it communicates with the face and nasal fossæ, and the primitive fissures are not obliterated. This state of the upper lip is termed liare-lip , and that of the arch of the palate is termed fissure of the palate. (1) Generally then the solution of continuity in the lip or palate, excepting in the uvula, does not correspond to the median line, but occurs on one of the two sides, since it is situated also like the fissures by which the lips communicated primitively with the face. Farther, in the simple fissure of the palate we generally remark that the anterior and intermaxillary portion of the upper maxillary bone on one side is separated from the posterior ; at least the solution of continuity is rarely situated on the median line, and the intermaxillary bones are seldom attached each to the corresponding maxillary bone, and the two maxillary bones with the 'palatine bones are not often separated symmetrically from each other and from the septum of the nasal fossæ. (2) The mode in which the uvula is developed explains why fissures in it are situated on the median line. (1) Sandifort, De labio leporino congenito, duplici el complicata ; in the Obs, anal, pathol., book iv., ch. iii. — Tenon, Sur quelques vices de la voûte palatale; in liis Mém. et obs. sur V anatomie, Paris, 1810, p. 296. It 13 curious that however great this deviation of formation, it sometimes disappears at a more advanced period, and assumes the normal conditions of the regular type ; the bony palate increases either alone or after the hare-lip is united, and the space between the oral and nasal cavities gradually fills up. This fact supports our previous conjecture that the two halves of the uvula sometimes unite in the fetus after the usual period of union. The oral cavity presents those alterations of texture observed in all the mucous membranes. One of the rarest anomalies of this class is the development of hairs, which have been observed once on the surface of an encysted tumor in the fauces of a newly born infant.(l) It has been asserted that they have been seen also on the tongue. (2) A. FOHM. § 2049 The lips (labia) are prolongations which coper the anterior face of the alveolar edge of the jaws, being parallel with it. Their loose edges which look towards each other are more or less enlarged and turned over, that of the lower always more than the upper. The opening between them is termed the mouth (os). The upper lip is longer and more prominent than the lower. We remark in it. on the median line a longitudinal depression called the phil tram, which extends from the septum of the nose to the place where the skin becomes much thinner. This depression is remarkable on account of the space which primitively existed at the same place between its two lateral halves. 2d. Because the depression of the upper lip seems to depend on the greater extent of the superior frenum, and on the separation of the superior maxillary bones, which always continues during life. § 2050. The different changes in the form of the cavity of the mouth, are produced by the action of the following muscles winch occupy the regions of the lips, the cheeks, and the chin. a. Orbicularis oris. § 2051. The orbicularis oris muscle, buccal , Ch. ( M . annularis , orbicularis oris, sphincter oris), principally forms the fleshy layer of the lips, surrounds the mouth, and is situated between the skin and the mucous membrane. It is oval, thin, flat and broad, and is formed of concentric fibres The external blend insensibly with those of its antagonists, or are prolongations of fibres of these different muscles which interlace together. These external fibres, however, are distinct, and are not blended. The internal form a separate order. They are found near the loose inner edge of the muscle and of the bps ; but they insensibly disappear in the external fibres. b. Buccinator. § 2852. The buccinator muscle, bucco-labial , Ch., is situated between the upper and lower maxillary bones and the orbicularis oris muscle. It is square, broad, thin, and flat. Its fibres have generally a transverse direction ; the upper, however, go obliquely from above downward and from behind forward, the inferior proceed in the opposite direction, and the central alone are straight. Its fixed points are the superior and the inferior maxillary bones. It arises from the external face of the alveolar edge of these two bones ; its attachments commence behind the last molar tooth, and extend to about the second anterior. It also arises at its posterior part from the summit of the internal wing of the pterygoid process, and from a ligament which extends from that point to the alveolar edge of the lower maxillary bone. It is blended forward with the orbicularis oris muscle. The canal of Steno passes through it, near its anterior extremity. It draws the lips and the whole mouth directly backward, contracts the cavity of the mouth, and consequently expels the substances in tins cavity, so that it acts in blowing, whistling, expelling liquids from the mouth, sucking, forming the mass of food on the tongue, and in swallowing. c. d. Zygomatici. § 2054. The zygomatici muscles, zygomato-labiaux , Ch., arc two in number, a large and a small (JVI. zygomalicus major el minor). Both are elongated and thin. The large is more round than the small, and is also situated further outward and backward. Both arise from the external face of the malar bone ; sometimes, however, the small comes only from the external and inferior part of the orbicularis palpebrarum muscle, which generally sends some fibres to them. Both go obliquely from above downward, from without inward, and from behind forward. They blend with the orbicularis oris muscle ; the small with that portion of this muscle which makes part of the upper lip ; the large with that which extends to the angle of the mouth and to the lower lip. • Sometimes the zygomaticus minor muscle is deficient; in other cases its lower extremity is bifurcated ; in some subjects it does not descend to the orbicularis oris muscle, but terminates in the outer face of the levator labii superioris arid the levator anguli oris muscles. These muscles draw the skin of the cheeks, the commissure of the lips, and the whole mouth, downward and outward. They consequently contribute to enlarge the mouth, particularly when they act on both sides at once. e. Levator anguli oris. § 2055. The levator anguli oris muscle, petit sus-maxillo-labial, Ch. (M. levalor anguli oris , s. caninus), is broader than the preceding, and is flat and elongated. It arises in the canine fossa below the infraorbital' foramen, descends almost perpendicularly, becoming thicker and narrower, and blends in the angle of the mouth behind the zygornaticus major muscle with the orbicularis oris, and still more with the depressor labii inferioris muscle. § 2056 The levalor labii superioris muscle, moyen sus-maxillo labial , Ch., is much larger than the preceding, and partly conceals its upper extremity, being covered in this place by the orbicularis palpe- brarum ; it has nearly the same form but a different direction, for it descends obliquely from without inward. It arises from the upper maxillary bone above the infra-orbitar foramen and is attached to about the middle of the upper lip, so that its fibres blend with those of the orbicularis oris, before which it descends. g. Anomalus faciei. § 2057. Below the preceding and the levator alæ nasi labiique superioris muscle we not unfrequently find a long muscle which arises near the canine fossa of the upper maxillary bone, and is attached directly above the origin of the preceding ; it is termed the anomalus faciei by Albinus :(1) the rhomboideus by Santorini. (2) This muscle has already been described. § 2058. The lower muscles of the mouth, considered in the same order as the preceding, are, the depressor anguli oris, the depressor labii inferioris, and the levator menti muscles. § 2059. The depressor anguli oris muscle, maxillo-labial , Ch., called from its form the triangular muscle of the lips , arises from the anterior part of the lower edge and the anterior face of the lower maxillary bone. It ascends, contracting and becoming thicker towards the angle of the mouth, where it blends with the orbicularis oris, the zygomaticus major, and particularly the levator labii superioris muscle, so as to form with this latter a single muscle very much contracted in its centre, the fibres of which, however, are not interrupted by a median tendon. When the lower part of the muscle formed by the union of the levator labii superioris and the depressor anguli oris acts alone, it draws the angle of the mouth and the lower lip downward, as in weeping. This muscle also enlarges the mouth transversely by its external fibres. When acting alone it contributes to raise the lower jaw. j. Depressor labii iiiferioris. § 2060. The depressor labii iiiferioris muscle, mento-labial , Ch. (quadratics menti), is thin and square. It is covered at its lower part by the preceding, and slightly above by the base of the zygomaticus major muscle ; it arises farther forward and lower than the depressor anguli oris muscle, ascends obliquely from without- inward towards the lower lip, interlaces and intercrosses with that of the opposite side by its upper and inner part, and terminates in the orbicularis oris muscle. k. Levator menti. § 2061. The levator menti muscle is small, thick, semicircular, and unmated. It is attached on each side to the anterior face of the lower jaw, below the alveolar process of the canine tooth, occupies the triangular space between the two depressor muscles, and terminates in the skin of the chin. § 2062. The palate ( palatum ) forms the arch of the mouth, which it separates from the nasal fossæ. We distinguish in it two portions, an anterior or osseous portion, and a posterior or soft portion. The osseous palate is composed of the horizontal or palatine portion of the superior maxillary and palatine bones, and also of the mucous membrane extended on their surface. This membrane incloses a layer of muciparous glands which is much thicker and more complex than that of the two preceding regions. § 2063. The soft palate, called also the veil of the palate ( palatum molle , s. velum palatinum ), forms a fold which extends obliquely from _ above downward and from before backward from the posterior edge of the horizontal portion of the palatine bones toward the base of the tongue. Its lower edge is loose, and presents in the centre a rounded prolongation, termed the uvula, (l) on each side of which is a fissure. These two fissured halves of the lower edge form the inferior arches oj the palate (Jl. palatini inferiores). The superior arches ( A . palatini The soft palate is formed of two layers of mucous membrane which cover its anterior and posterior faces, and are continuous with the pituitary membrane, of a very dense layer of muciparous glands situated between the two membranes, and of several muscles which contract and vary the form of the isthmus of the fauces ( isthmus faucium). A prominence resembling a cicatrix exists along the anterior face of the soft palate and the greater upper part of the uvula ; this marks the primitive division of this part into two halves. § 2064. The muscles of the soft palate are distinguished into those which depress it and those which raise it. The first contract the isthmus of the fauces, the latter dilate it. The muscles which contract the isthmus of the fauces are situated in the two arches ; those which dilate it descend from the base of the skull and are directed from without inward. § 2066. The palato-pharyngeus muscle or the superior constrictor •of the isthmus of the fauces (JVf. palalo-pharyngœus, s. constrictor isthmi faucium superior ) arises from the upper part of the lateral wall of the pharynx, where its fibres blend with those of the superior and middle constrictors. Thence it enlarges, goes upward and inward, enters the soft palate, divides into an anterior and a posterior layer, which receive between them the levator palati mollis muscle, extends to the posterior extremity of the bony palate, and unites on the median line with that of the opposite side. § 2067. The glosso-pharyngeus muscle, of the inferior constrictor of the isthmus of the fauces {M. glosso-pharyngceus, s. constrictor isthmi faucium minor, s. inferior, s. proprim ), a similar but much smaller muscle, ascends from the root of the tongue in the soft palate before the palato-pharyngeus muscle, with which it unites and arrives § 2069. The levator palati mollis muscle (JVT. levator palati mollis, s. petro-salpingo-staphylinus), pétro-staphylin, Ch., is oblong and almost rounded ; it arises from the centre of the anterior edge of the petrous process, and from the osseous portion of the Eustachian tube, and also from the posterior part of the commencement of its cartilaginous portion, by a short and strong tendon, goes inward and downward, enlarges but becomes thinner, and blends with that of the opposite side ; it forms in the soft palate between the two layers of the palato-pharyngeus muscle an arch the convexity of which looks upward and the concavity downward. b. Tensor palati mollis. § 2070. The tensor palati mollis muscle, ptérygo staphylin, Ch. (M. tensor palati mollis, circumflexus palati, plerygo-salpingo-staphylinus), is broad, thin, and quadrilateral. It arises a little inward and forward from the upper extremity of the pterygoid process behind the pterygoid fossa on the inside of the oval foramen of the sphenoid bone ; it frequently comes also from a greater or less exteht of the posterior edge of the internal layer of the pterygoid process, and from the outside of the cartilaginous portion of the Eustachian tube. It goes inward and downward and becomes a flat tendon, which turns on the hook of the pterygoid process, a mucous bursæ existing between them ; it is attached by its anterior edge to the posterior edge of the palatine arch, and always blends with the tendon of that of the opposite side to form the upper part of the soft palate. § 2071. The uvula or the central portion of the palate, the base of which is pointed, is composed of numerous muciparous glands, which are every where surrounded, sometimes by one sometimes by two muscles, termed the palato-staphylinus (M. uvulœ , s. azygos uvulœ) This muscle is always very long, and descends from the palatine spine and the anterior face of the tendon of the tensor palati mollis muscle. By contracting, it shortens the uvula. also of speech and deglutition. We may consider it as the lower part of the cavity of the mouth, and consequently of the alimentary canal, which is considerably enlarged, and which from this fact projects within the cavity. thin from behind forward. Its posterior part is termed the root, and the anterior part the point or apex. It extends forward and on the sides much beyond its base of support, so that it is loose in these two regions, which form most of it. Its integuments are uninterruptedly continuous with the buccal membrane, which forms below its point a longitudinal fold of a very firm tissue, which is attached to the centre of the inner face of the lower maxillary bone, fixes the organ more firmly to the part it occupies, and is termed the frcenum linguae. the muscles of the hyoid bone and the proper muscles of the tongue. (1) M. Malpighi, De lingua , Bologna, 1665. — G. Fracassati, De lingua. — L. Bellini, Gustus organon novissime detectum, Bologna, 1665. — L. Heister, De lingua sana et œgrota, Altdorf, 1716. — A. F. Walter, De lingua Humana, Leipsic, 1724. — J. Reverhorst, De fabriea et usu linguae, Leyden, 1739.— Royen, De fabrica el usu linguae, Leyden, 1742. — J. A. Rinder, -De linguae involucris, Strasburg, 1778. — Bauer, Sur la structure de la langue ; in the Journal compl. des sc. méd., vol. xiv., p. 181. — Gerdy, Discussions et propositions d'anatomie, de physiologie et de pathologie, Paris, 1823, p. 19, pl. i. and ii. — Blandin, Sur la structure et les movvemens de la langue ; in the Archiv, gén. de méd., vol. i., p. 437. 1. Mylo hyoideus. § 2074. The mylo-hyoideus muscle transversus mundibulœ, s. mylo-hyoideus) fills the larger anterior part of the space between the two halves of the lower jaw, viz., the two halves of the horizontal portion and the body of the hyoid bone. It is loose outward in nearly its whole extent, and is covered in its centre by the anterior belly of the digastricus muscle of the lower jaw. It is a triangular and thin muscle, the external convex edge of which arises from a corrugated line on the inner face of the horizontal portion of the lower jaw, and proceeds from before backward and from within outward. It enlarges considerably from before backward. Its anterior fibres are transverse. The posterior are directed from before backward and from without inward, and proceed toward those of the opposite side. It descends from without inward, and unites with the latter on the median line, being separated from it only by a narrow tendinous band which extends from before backward to the single muscle formed by this union. It is attached by the inner portion of its posterior edge to the centre of the anterior face of the middle piece of the hyoid bone. This muscle supports those of the tongue, which rest on it, and also the sublingual gland, compresses the canal of Wharton, and the excretory ducts of the sublingual gland, sustains these parts, and- raises the hyoid bone. § 2075. The genio-hyoideus muscle is situated directly above the centre of the preceding, next to the synonymous muscle of the opposite side. It has the form of a very elongated triangle, and arises from the upper part of the anterior face of the body of the hyoid bone, goes from behind forward and from below upward, gradually becomes thinner and rounder as it ascends, and is attached to the lower part of the internal mental process directly above the mylo-hyoideus muscle. Its anterior and posterior attachments are by very short, tendinous fibres. It draws the hyoid bone upward and forward. When this bone is fixed by its depressor muscles it brings the lower jaw downward and backward, so that it acts like the digastricus muscle of the lower jaw. Sometimes it is deficient, or rather it is imperfectly developed, and is replaced by a smaller muscle, which arises from the median tendon of the preceding, and is attached to the digastricus muscle.(l) § 2076. The stylo-hyoidèus muscle (JVT. stylo-hyoideus, s. levator ossis hyoidei) is thin, elongated, and rounded. It arises bj a short tendon at about the centre of the external face of the styloid process, goes forward, downward, and inward, presents near its lower extremity a fissure for the tendon of the digastricus muscle, and is attached to the anterior half of the external edge of the large horn of the hyoid bone opposite the thyro-hyoideus muscle. § 2077. The sterno-hyoideus muscle (JVT. depressor ossis hyoidei , s. sterno-hyoideus ) is thin and elongated. It conies from the inner face of the first piece of the sternum and of that of the cartilage of the first rib, and sometimes also from the inner extremity of the clavicle ; thence it goes directly upward, in its course approaching that of the opposite side, and becomes thicker and narrower. It is finally attached to the lower edge of the middle piece of the hyoid bone, directly at the side of the median line. It draws the hyoid bone downward, and as this bone is attached to the lower jaw, when the other is not fixed by its levator muscles, it is also depressed so that it acts on opening the mouth. § 2078. The omo-hyoideus muscle, scapulo-hyoidien , Ch. (JYI. retractor ossis hyoidei , omo-hyoideus , coraco-hyoideus ), is a very long, thin, and digastric muscle. Its inferior belly arises from the upper edge of the scapula, sometimes also from the small ligament extended over the coracoid fissure ; goes upward and forward ; between the sternocleido-mastoideus and the scalenus anticus muscles it becomes a tendon whence the superior belly arises, which is attached to the middle piece of the hyoid bone on the outside of the preceding, and blends more or less with the stylo-hyoideus muscle. deficient : we have observed it once, on the left side, without a substitute. Its origin frequently varies. Sometimes the inferior belly is broader, so that it extends to the upper angle of the scapula.(l) Sometimes it arises from the clavicle,^ 2) and it is then unusually short. In some subjects the lower belly is divided into two heads, to which its simple enlargement is an approximation. (3) One of these heads is sometimes attached to the clavicle. (4) In some cases it unites with the sterno-thyroideus muscle by its superior belly or by a special head. (5) More rarely it is not inserted in the hyoid bone but in the transverse process of the sixth(6) or second ? cervical(7) vertebra. § 2079. The genio-glossus muscle (JVl. txpulsor , utlrahens linguae, s. genio-glossus), the largest of all the muscles of the tongue, arises from the lower jaw by tendinous fibres which aïe inserted directly above the genio hyoideus muscle. It is situated against that of the opposite side, which it does not leave because its direction is that of the median line ; it goes backward, enlarges much like a fan, and forms the greater inner part of the tongue the whole length of this organ. It also gives off some fibres which go outward, pass on the following muscle, sends several to the upper part of the pharynx, and furnishes a few to the upper horn of the hyoid bone and the epiglottis. § 2080. The hyo-glossus muscle (JVT. depressor linguae, s. hyoglossus, s. basio-cerato-chondro-glossus) is thin, and has a long square form. It arises from the outer part of the body of the bone, from the external edge of its great horn, and from the summit of the small horn, ascends toward the lateral part of the tongue, and contributes to form it. § 2081. The stylo-glossus muscle (JVE. retractor linguae , s. styloglossus), the shortest of the small muscles which come from the hyoid bone, arises directly from its summit and also from the upper part of its circumference, and arrives at the root of the tongue, in which it expands like a fan to its point, interlacing more or less with the hyoglossüs and the genio-glossus muscles. 4. Lingualis. § 2082. The lingualis muscle is thin and narrow. It extends from before backward the whole length of the tongue, and interlaces principally with the hyo-glossus and the genio-glossus muscles. conclusions are as follow : The tongue is composed of a membrane, a peculiar yellow tissue, a superficial lingual, two deep lingual, the transverse lingual, and the vertical lingual muscles, all of which are distinct, of the two stylo-glossi, the two liyo-glossi, the two genioglossi, the two glosso-staphylini muscles, and the fasciculi of the hyo-glosso-epiglossus. the subjacent muscular fibres are inserted. The yellow tissue covers at the base of the tongue the enveloping membrane, which has no cartilaginous texture in this place. It adheres to the hyoid bone, to the epiglottis, and to many muscular fibres. Follicles exist within it. The superficial lingual muscle covers the upper face and the edges of the tongue, adheres closely to its membrane, and is attached posteriorly to the yellow tissue. Its fibres go forward, some on the upper face of the tongue, converging: toward the median line, others above and below its edges to its apex. The deep lingual'muscles are two small fasciculi situated on each side under the posterior two thirds of the tongue, between the hyo-glossi and the genio-glossi muscles. Their fibres are attached posteriorly to the yellow tissue. The transverse lingual muscles are situated under the superficial lingual, pass through the whole breadth of the tongue and between the lateral fibres of the superficial lingual muscle, which they cross at a right angle, and are attached to the membrane of the tongue under the edge of this organ. They are divided on the median line by a fibro-cellular raphe. They gradually curve more and more towards the base of the tongue. The vertical lingual muscles extend from the upper to the lower lingual membrane, passing through the whole thickness of the tongue and the transverse lingual muscles, with which they intercross. They curve and become more and more oblique toward the base of the organ. The fibres of the stylo-glossi muscles blend with those of the superficial lingual muscle above and below the edges of the tongue, and send a transverse fasciculus under the yellow tissue, which unites to that of the opposite side. § 20S3. The mucous membrane which covers the tongue is characterized principally by the great development of its papillary tissue, and by the facility with which the epidermis is detached from it. served are : 1st. Folds. These folds are seen principally on the posterior part and on the edges of the tongue. They are generally arranged regularly, converge from without inward and from before backward, and are very compact. They are about half a line high and broad. The anterior present numerous transverse grooves. The posterior are smooth, and consequently their surface is less extensive than that of the preceding. Those at the most anterior part of the tongue are less regular and constant. In the middle of the back of the tongue there is frequently a more or less evident longitudinal depression. 2d. Papillæ. (2) The papillæ of the tongue are arranged very compactly, and cover almost all its dorsal face. They are insulated only at the root of the organ, where also they enlarge very much. The genio-glossi muscles are situated side by side on the inside of the hyo-glossi and the deep lingual muscles : their fibres radiate from the malar process to the three posterior fourths of the tongue, on the median line, to the hyoid bone, the yellow tissue, and the lingual membrane. They pass from below upward through the transverse and the superficial lingual muscle, and curve slightly upward and outward in the thickness of the tongue. The hyo-glos30 epiglossus is formed of small fasciculi, generally deficient in man, which go from the hyoid bone to the yellow tissue, others from this tissue to the epiglottis, others also from the epiglottis to the hyoid bone. F. T. We must however remark, that in this respect they are frequently replaced by single filiform papillæ, which are longer and larger than the others. The fungiform papillæ lead to the largest of the papillæ of the tongue, which are situated at the base of the organ, vary much in number and size, and are arranged in two oblique series, which touch at one of their extremities, and thus form a V, the point of which looks backward. Their form is generally but not always conical, so that they enlarge considerably from their base to their extremity. They are situated in a depression which is continuous with the surface of the tongue by a sack with reversed edges. They are termed ihelenticular papillæ (papillæ truncatœ,capitatœ,circumvallatœ') : they are from three to twenty in number. Each depression commonly contains only one, but sometimes three or four, although this circumstance has no effect on their whole number or on their size. They are not arranged symmetrically, although generally there is one which corresponds very nearly to the median line, and forms the point of the V. This latter occupies the deepest of all the cavities, that which is termed the lacuna , the foramen cæcum of the tongue ; beside which there is another situated behind it, and which incloses no papillæ. We have several times thought, but wrongly, that we have discovered in this foramen cæcum the excretory ducts either of the salivary glands or of the thyroid gland.(l) § 2084. The papillæ of the tongue appear to the naked eye, and frequently when viewed by the microscope before they are injected, smooth in their whole extent and single ; but when their vessels are injected, their surface presents several small asperities, which seem formed by collections of several fasciculi or filaments, placed one against another. This texture is more apparent in the larger and anterior, than in the smaller and posterior part. Each filament contains at least one vessel ; and when well injected, the whole surface of the tongue becomes red. These vessels form very complex arches and plexuses on the surface of the papillæ, since they frequently anastomose, and their loose extremities incline toward each other. Each filament is also composed of a soft and whitish mass which probably contains nervous substance. At least some filaments of the glosso-pharyngeal nerve have been traced into the posterior papillæ of the tongue, and some filaments of the lingual branch of the fifth pair into the others. The arrangement of the vessels is more apparent in the anterior than in tho posterior papillæ of the tongue, because they inclose proportionally more mucous tissue. (1) § 2085. Behind the lenticular papillæ, the surface of the tongue is smooth, presenting only numerous muciparous glands ; its sides are also smooth. We only remark on the limit between them and the lower part of the cavity of the mouth, the orifices of the excretory canals of the submaxillary gland. § 2086. The tongue is covered in every part, especially on its upper face, by a thick, whitish and moist epidermis, (periglottis)( 2), which is formed exactly like the papillary tissue, and which consequently presents on its upper face numerous elevations, and on its lower face, which looks towards the papillæ, a corresponding number of rounded depressions, so that at first glance it seems perforated with foramina, although this is not the case. § 2087. We have already described the nerves of the tongue, and have given our reasons for thinking the lingual twig of the fifth pair is the principal conductor of the sensations of taste, while the hypoglossal nerve should be considered as only the nerve of motion. Although the tongue receives many nerves, and although its surface is very sensible, its substance is but slightly so. This explains how it can be very much bruised, or how considerable portions of it may be tied, without giving rise to general nervous affections. (3) mentary canal. The faculty of taste resides principally at its point, next on its edges, finally at its base, and very slightly or not all in its centre. It however is not the only organ of taste, for the soft palate is sensible, at least to certain tastes, for instance that of bitter substances. Hence why the loss of the tongue is not necessarily attended with that of taste. The tongue assists also in articulation, inasmuch as several consonants hence termed lingual , are formed, or at least articulated more distinctly, by its motions in different directions. It also contributes to change the food in the mouth by carrying it to different parts of this cavity, so that it becomes perfectly moistened with the saliva, and also prevents its escape from the mouth. § 2089. The changes in the tongue during its development are trifling. At first its proportional volume is greater than when the organism is perfect. It is also broader, and is attached to the lower wall of the cavity of the mouth in a smaller portion of its lower face, which resembles to a certain extent the peculiar formation of frogs. and the posterior. The anterior are more insulated and lenticular. Then greatest diameter is only two lines, and they are found principally in the lips and cheeks, opposite the upper posterior molar teeth, between the buccal membrane and the muscles it covers, They are divided according often speak of negroes swallowing their tongues. Superficial observers have been led into error by a phenomenon which is proved possible by Bourdon’s researches, in giving reason to think, that the greatest effort in a robust person would cause death, and thus in some measure one commit suicide. ( Recherches sur le mécanisme de la respiration et sur la circulation du sang , Paris, 1820, p. 84.) F. T. to their situation into labial, buccal, and molar ( gl . labiales, buccales, et molares ). These latter are rarely blended in one mass, the excretory passages of which unite in one. The posterior are the palatine glands and the amygdalae. The palatine glands (gl. palatincz ) form a continuous layer from one to two lines thick, which covers all the palatine arch and all the soft palate, the posterior face of which they occupy. The amygdalae or the tonsils (Amygdalae, s. tonsillœ) are oval bodies, about six lines long, three thick and broad, which exist in the soft palate between the anterior and posterior arches. The fluid they secrete enters the cavity of the mouth through several broad openings, situated on their anterior face. b. Salivary Glands. § 2093. The three oral salivary glands (gl. salivates orales ) which belong to the class of conglomerate glands(l) are situated around the cavity of the mouth and near the lower jaw. They are the parotid, the submaxillary, and the sublingual glands. All secrete a peculiar fluid, the saliva, (2) which is one of the most aqueous fluids of the body, and contains a peculiar principle which cannot be coagulated by boiling, by tannin, or by the acetate of lead. We also find in it a white mucous substance, and the common salts of the serum of the blood. It is also remarkable for its great affinity for oxygen.(3) Beside the general characters of the class to which they belong, these glands also present several common peculiarities, the principal of which are as follow. 1. Their rounded form. 2. Their reddish color. 3. They have no special membranous capsule, are surrounded only by condensed cellular tissue, and are loosely attached to the adjacent parts. 4. They are so situated that they are affected by the mechanical action of the muscles, and even partly by that of the lower jaw when it is moved. 5. The fluid they secrete possesses probably in every part the same properties. each of them separately. (1) N. Stenon, De glandulis oris et nuper observatis inde prodeuntibus vasis, Leyden, 1661.— A. Nuck, Sialographia ductuwm aquosorum anatome nova, Leyden, 1690. — J. B. Siebold, Historia Systematis salivalis physiologice et pathologice considérait, Jena, 1797. (3) Berzelius, Fortscritte der thicrischen Chemie, Nuremberg', 1815, p. 47. — John, Recherches chimiques sur la salive et la liqueur que les ventricules de cerveau renferment dans l'hydrocéphale ; in the Joum, compl. des sc. méd., vol. vi., p. 270. gland, and in the adult it usually weighs from four to five drachms. Its form is irregularly square. It is usually more high than broad, narrower from within outward than in any other direction, and its thickness is much less than its height and breadth. Its lower half is considerably thicker and broader than the upper. It is situated directly under the skin, before the lower half of the external ear, between the space in the ascending ramus of the lower maxillary bone forward, and backward between the auditory foramen and the mastoid process of the temporal bone. Its upper extremity, which is also the smallest edge, extends to the posterior extremity of the zygomatic arch, and covers the head of the ascending ramus of the lower maxillary bone. Its smaller anterior half corresponds in its whole extent to the posterior part of the ascending ramus of the lower maxillary bone and of the masseter muscle. The posterior half is larger than the preceding, and fills the space we have mentioned. It covers the petrous portion and the styloid process of the temporal bone, also the external parts of the pterygoidei muscles and the upper part of those which arise from the styloid process. Posteriorly, the gland terminates by nearly a straight edge, which is, however, slightly grooved anteriorly. Its lower extremity descends below the angle of the lower jaw ; it is in contact with the posterior part of the submaxillary gland, and with the middle tendon of the digastricus muscle. The lower straight edge descends obliquely, covers the posterior belly of the digastricus muscle, and also generally a small portion of the upper extremity of the sterno-cleido-mastoideus muscle. At about the upper extremity of the middle third of its anterior edge an excretory duct emerges, called the canal of Steno ( ductus Slenonianus)(2) The parietes of this passage are considerably thick in proportion to its capacity, and it proceeds from behind forward and (2) Although this term is generally applied to the parotid canal, it is not certain that it was discovered by Steno, and not by Needham or Blaes. — N. Steno, Diss. dc glandulis oris ct nuper observatis inde prodeuntibus vasis, Leyden, 1661. — Id., Obscrv. anat. quibus varia oris, oculorum et narium vasa describuntur, noviqve saliva: lacrymarumque et muci fontes detegunlur ct novum Bilsii commentum rejicfur Leyden, 1662.— Needham, De formatu fœlu, London, 1667; in the preface.— G. Blaes, Mise. an. horn, brutorumquc fabricam diversam exhibentia, Amsterdam, from without inward directly under the skin and on the masseter muscle. It is generally from three to five lines distant from the lower edge of the zygomatic process. The transverse facial artery and some twigs of the facial nerve accompany it. It passes on the anterior edge of the masseter muscle, penetrates between the fibres of the buccinator muscle, and opens in the lateral walls of the cavity of the mouth opposite the first posterior molar tooth of the upper jaw, consequently before the range of the teeth. Its orifice is single, and presents a warty prominence. We not unfrequently find an accessory parotid gland ( Gl . parotis acccssoria ), situated more or less before the normal parotid gland, on the malar bone and the zygomatic arch. This gland never communicates with the proper parotid gland, and sometimes divides into two lobes ; it opens by a small passage into the parotid candi. It may be compared with the orbitar gland of several mammalia. § 2095. The submaxillary gland (67. maxillaris , s. submaxillaris)(\ ) is but half the size of the parotid gland. It has the form of a rounded triangle. It is thicker below than above, and is situated on a level with the angle of the lower jaw, between its inner face and the body of the hyoid bone. On the outside it touches the lower part of the inner face of the pterygoideus internus muscle. Forward it sends a small prolongation above the posterior edge and the posterior part of the lower face of the rnylo-glossus muscle. It rests inward on the posterior extremity of the anterior belly of the digastricus muscle, posteriorly on the styloglossus muscle. ever, composed of much larger lobes. The excretory duct, called the canal of Wharton ( ductus Whartonianus), arises from the anterior extremity ; its parietes are very thin in proportion to its diameter, and it is larger compared with the size of the gland than the duct of Steno. Its direction is obliquely from without inward and from behind forward ; it passes above the rnyloglossus muscle, below and on the inside of the submaxillary gland, on the outside of the upper edge of the hyo-glossus muscle, and terminates by a small verrucous prominence on the sides of the frenum of the tongue, consequently behind the range of the lower teeth. Farther inward the substance of the gland sends off a prolongation some lines thick, which follows the same direction, but does not extend so high, passes through the inner part of the posterior extremity of the sublingual gland, and opens at the side of the canal of Wharton, sometimes in common with a small excretory duct which leaves this latter gland. This common duct is called the canal of Bartholini (ductus Bartholinianus).( 1 ) c. Sublingual gland. § 2096. The sublingual gland (Gl. lingualis, s. sublingualis)(2) is situated before the preceding, so that the posterior extremity touches the anterior extremity of the latter, occupies on each side the whole length of the tongue, and may be found directly under the buccal membrane, through which it is easily felt, and is even visible, on account of its inequalities and prominences. It is situated between this membrane, the myo-glossus, the genio-glossus, the genio-hyoideus, and the hyo-glossus muscles. It is formed like an elongated triangle, and it is nearly as large as the submaxillary gland. It is composed of smaller lobes than the preceding, is whiter and harder than it, and opens not like the two glands previously described by one orifice, but by several, usually seven or eight ; it, however, forms no distinct excretory duct. We perceive these openings on the lower face of the cavity of the mouth on each side below and near the tongue. There are also several ducts from its anterior portion ( ductus Riviniani ), which unite with that of the submaxillary gland ; sometimes one only anastomoses with a passage formed by a division of this latter, and thus give rise to the passage of Bartholini (§ 2095). § 2097. There are in fact no other salivary glands or other passages which carry saliva. Although several anatomists(3) have admitted others, it has long been proved that the parts considered as such are simply those of the muciparous glands at the root of the tongue or around the larynx, or even of the veins of the back of the tongue. (4) (2) A. F. Walther, De lingua Humana novis inventis octo sublingualibus salivœ viis , nunc ex suis functionibus , glandulis sublingualibus eductis , Leipsic, 1724. — C. J. Trew, De tasis linguae salivalibus atque sanguiferis epistola, Nuremburg, 1734. (3) A. Vater, Novus ductus salivalis, qui in linguæ superficie superior e circa ejus medium notdbili orificio hiat, Wittemberg, 1720. — Id., Novus ductus salivalis isque prœcipuus in lingua excretorius glandulœ insignis ad latera linguæ et sub eadem sitce itemque super radicem linguæ , epiglottidem , circa glottidem super arytœnoideas usque intra œsophagum expansæ, Wittemberg, 1721. — Id., De ductu salivali in lingua noviter antehac detecto, nunc dilucidato, confirmato , novisque experiments adducto, una ductus excretorius tonsillarum ac glandulæ thyrcoideœ, Wittemberg, 1723. — G. D. Coschwitz, De ductu salivali novo , Halle, 1724. — Id., Continuatio observationum de ductu salivali , Halle, 1729. this causes the saliva to flow outward, and thus forms salivary fistula. The closing of the orifice of the excretory canal of the submaxillary gland is often at least the cause of ranula , although this affection depends very frequently on a newly-formed cyst.(l) inflammation is situated in the cellular tissue between its lobes. So too the general alterations of texture, as scirrhus and cancer, which are also attended with an increase of volume, generally occur not in the glandular tissue, but in the lymphatic glands, which are situated on the inside and below the salivary glands, since the glandular tissue is generally unaffected in this case. (2) The tumors developed in the lower jaw are also situated in the lymphatic glands of the neck. Sometimes we meet here, as in other parts of the system, accidental ossifications with formations entirely abnormal. (3) Calculous concretions are formed in the amygdalae and the salivary passages, especially in the excretory ducts of the submaxillary gland. These calculi are composed, according to Fourcroy,(4) of an animal matter and of phosphate of lime. If however we may judge from external characters, a salivary calculus described by us(5) seems more similar to those biliary concretions which have cholesterine for their base. The calculi developed in the amygdalæ are of a dirty white color. The disagreeable odor which they generally possess probably depends,(6) at least in great part, on the decomposition of animal matter which surrounds them and enters into their composition ; for frequently this matter alone is very disagreeable, and, like the forma- (4) Syst, des conn, chim ., vol. ix., p. 312. — John has found nothing- else in two salivary calculi, one of which come from th,e tissue of the parotid gland : Chemische Zerlegung einer Concretion der Parotis; in the Deutsches Arch, für die Physiologie. vol. iv., p. 602 : Chemische Zerlegung einer Speichelsteins ; same journal, voL vi., p. 603. V. TEETH. § 2100. The teeth (dentes) { 2) are the hardest parts of the body. In their chemical and physical properties they resemble the bones, but they differ from them in their mode of union with the body, in their mode of development, and in their vital phenomena. In all these respects they are more similar to the epidermoid parts, particularly the nails and hairs. § 2101. 1st. Situation. The teeth are inserted in most of their extent in the alveolar processes of the two jaws, which closely embrace them, and articulate with them by gomphosis. The portion in the alveolar process is termed the roowradix dentis ). The rest of the tooth,ls not free. The centre, which is the smallest part, is termed ihe neck ( collum , s. corona dentis), and is surrounded by the gum 5 -all the portion above projects, and is exposed in the cavity of the mouth ; this is the body or crown of the tooth (corpus, s, corona dentis). (2) Treatises on the teeth generally treat of their anatomy, physiology, pathology, and therapeutics, and differ only by speaking more at length on one of these heads. We mention several works almost entirely pathological, as many of them contain a number of special or general remarks in regard to their anatomy and physiology : Eustachius, De dentibus libellus, Venice, 1563. — B. Martin, Dissertation sur les dents, Paris, 1679.— A. C. G. Cumme, Diss. sist. dentium historiam, Helmstadt, 1715. — P. Fauchard, Le chirurgien dentiste, ou traité des dents, Paris, 1728. — Lecluse, Nouveaux élémens d'odontologie, Paris, 1754. — Bourdet, Recherches et observations sur toutes les parties de l'art du dentiste, Paris, 1757. — Curtis, A treatise on the structure and formation of the teeth, Oxford, 1769. — F. X. de Wasserberg, Aphorismi anatomico-physiologici de dentibus, Vienna, 1770.— J. Hunter, Natural history of the human teeth, London, 1778. — H. G. Courtois, Le dentiste observateur, Paris, 1775. — Broussonet, Considérations sur les dents en général et sur les organes qui en tiennent lieu ; in the Mém. de l’ac. des sc., 1787, p. 550. — A. G. Berger, Diss. de dentibus, Kiel, 1788. — S. H. Bring, Observationes in hodiernam de dentibus, præcipue hominum, doctrinam, Lund, 1793. — F. — R. Blake, Essay on the structure and formation of the teeth in man and various animals, Dublin, 1801. — J. Fox, Hist. nat. et maladies des dents de l’esp. humaine, Paris, 1821. — A. Serres, Essai sur l’ anatomie et la phsiologie des dents, ou nouvelle théorie de la dentition, Paris, 1817. — F. Lavagna, Esperienze e riflessioni sopra la carie dei denti, Genes, 1821. — Heilbronn, Diss. de dentibus, Berlin, 1821. — C. G. Kaathover, De dentium formatione atque natura, Leyden, 1821. — J. Lemaire, Traité sur les dents, Paris, 1822. The root and neck of the teeth are covered with a thin membrane ; this is continuous below with a nervous and vascular tissue which fills the cavity of the tooth, and above with the gum ; it is termed the dentar periosteum , although the history of dentition seems to demonstrate that its relations with the teeth are not the same as those between the periosteum and the bones. The alveolar processes are also covered by a fibrous and thick membrane, which in the normal state does not unite with the preceding, but is continuous with the upper part of the gum, and is termed the alveolar periosteum. The gums ( gengivœ ) are a firm, resisting cellular tissue about half a line thick, which adhere intimately with the buccal membrane, and receive but few vessels or nerves. They cover the neck of the teeth, and also the two faces of the alveolar edges of the jaws, and furnish thin prolongations which extend between each two teeth, from the anterior to the posterior face. backward and convex forward. They are generally arranged very compactly, and are placed at equal distances from each other. The upper and the lower touch at their summits. The arch formed by the upper teeth is a little longer than the other. Hence the upper teeth slieîtly project outward, and the anterior, which are thinner, cover the otimrs. The posterior and inferior t#eth have their summits slightly inclined inward, while those of the uppesare turned more directly downward. 2d. Form. All the teeth are more or less elongated ; their lower extremity is slightly pointed, and there presents a small opening which leads into the cavity of the tooth ( cavum dentis). This cavity extends from the summit of the roots to the crown, and is very narrow in proportion to its length, represents the form of the tooth, and lodges its vessels and nerves, which are connecte I by cellular substance. are composed of two substances, the osseous substance and the enamel. § 2102. The osseous substance or the ivory forms the largest part of the tooth, the root, the neck, and almost all the crown. It consequently represents the form of the whole tooth. Its hardness, which exceeds that of the bones, depends upon its mechanical arrangement and on its chemical composition. In fact it contains no cellules. We perceive in it but not very clearly only longitudinal layers, situated one upon another from without inward, and it contains more of lime than the other bones. Berzelius asserts(l) that one hundred parts of this substance contain 51.04 of phosphate of lime ; 2.00 of fluate of lime ; 11.30 of carbonate of lime ; 1.16 of phosphate of magnesia ; 1.20 of soda ; and an indeterminate quantity of hydrochlorate of soda. Pepys states that they contain 0.64 of phosphate of lime; 0.6 of the carbonate; 0.20 of gelatine; and 0.10 of water, incluhng the loss.(l) I 2103. The enamel {substantia vitrea) (2) is milk white, brilliant, semitransparent, and still harder and firmer than the osseous substance. It covers all the crown of the tooth, is molded exactly upon it, and preserves all the inequalities of its masticating surface, where it is thickest. It gradually grows thinner towards the neck. It is composed of oblique, undulating, serrated bands, concave upward, convex downward, which are arranged compactly from above' downward, and exactly fit to each other.(3) The enamel contains still more of earthy salts than the osseous substance. We find in it, according to Morichini :(4) 0.33 of lime ; 0.09 of magnesia ; 0.05 of alumina ; 0.22 of fluoric and phosphoric acids ; Ö.01 of carbonic acid ; and 0.30 of animal substance. Finally, Berzelius(8) mentions as its component parts : 85.3 of the phosphate ; 3.3 of the fluate ; 8.0 of the carbonate of lime ; 1.5 of the phosphate of magnesia ; and 2.0 of animal substance and water. § 2104. The vessels and nerves of the teeth are proportionally very large. The first arise from the internal maxillary artery ; the nerves come from the second and third branch of the trifacial nerve, penetrate through the openings at the summit of the roots, correspond perfectly to them in number, descends into the cavity of v the tooth, where, united by cellular tissue, they form the nucleus or pulp of the tooth ( pulpa , s. nucleus). These nerves enlarge near the neck of the tooth, 4th. The period of life at which they appear. § 2106. In respect to situation , the most general difference is that which exists between the teeth of the upper and those of the lower jaw. The latter differ from the former in being a little smaller, so that the curve represented by their union is narrower and shorter ; hence the upper row of teeth projects a little beyond the lower in every part. molar teeth. § 21 OS. The incisors ( dentes incisivi , incisores, primores ) are eight in number, four in each jaw, occupying the most internal and the most anterior part. They differ most from the others in the form of their crown. The latter is chisel-shaped, and becomes much thinner from the neck to the summit, which presents the cutting surface. The posterior face is vely concave and the anterior is convex, but not in the same proportion. The incisors begin to become extremely thin from their centres. In the perfect state, when they have not been used for mastication, their edge is divided into a middle and two lateral small grooves ; but these grooves soon disappear, and the summit of the tooth then forms only a- thin straight line, which extends the whole breadth' of the crowp. , These teeth have but one root. It diminishes imperceptibly from the crown to its extremity. A depression not unfrequently exists its whole length on each side, indicating the division of this root into two halves, an anterior and a posterior ; and even the summit is divided into two small grooves, an anterior and a posterior. The incisors differ from the other teeth in their direction ; they are situated more transversely, so that their loose face looks forward ; the other is turned backward, and their cutting edge extends from one side to the other. §2109. The incisors also differ much from each other. The difference between the synonjnnous teeth of the two jaws is no where so striking as in them, even when they are most similar in size. Those of the upper jaw, however, extend half a tooth farther outward than The incisors of the lower jaw differ also from the others both in size and for«. In fact they all have a chisel-like form, and their external edge is about as high as their internal. Sometimes, even, they are all similar in this respect. But most commonly their external edge descends a little lower than the internal, and is continuous with the other by a rounded angle. The internal inferior incisors possess this form very seldom, and the others very generally. In the external superior incisqjs the internal edge is a little convex outwardly, and is insensibly continuous with the lower, although a little farther downward, so that the cutting surface is narrower than the greatest breadth of the tooth. These differences in form deserve notice, as they establish the gradual transition from the internal inferior incisors to the canine teeth through the medium of the others. In respect to the size, the inner pair of incisors in the upper jaw are a little and ofteir much larger than the outer ; while in the lower jaw the incisors are about the same size, or the outer pair is a little larger than the inner. § 2110. Next to the incisors come the four canine teeth ( dentes canini , ferini, cuspidati ), one on each side. Their crown is much thicker from before backward than that of the incisors, but it does not diminish as rapidly from above downward ; hence why their summits are less cutting. This summit is also pointed, because the lower face does not describe a straight line, as the two lateral faces terminate higher than in the incisors, and as the crown of the canine teeth is as elevated as that of the latter, it follows that the lower face is composed oftwo parts which unite in the centre at an acute angle, Consequently the crown is more rounded and more conical ; it extends both inward and outward above that of the incisors. On the posterior face we perceive from ab^ve downward in the centre a slight prominence, between which and the edges there is a small depression. This arrangement is more evident in the inferior than in the superior canine teeth. Of all the teeth the canine have the longest roots. These roots are single and pointed. We generally observe in them the groove mentioned when speaking of the external incisors. § 2111. In the posterior part of the jaw are the twenty molar teeth (dentes molares), ten in each jaw, five on each sid^ They are similar to each other, and differ from the other teeth : 1st. In the greater breadth of their triturating surface, which depends on the fact that the posterior face of the crown does not descend obliquely to meet the anterior, but is parallel with it. division is only indicated. § 2112. Notwithstanding this general similarity they differ very much’ particularly the two anterior and the three posterior. The first are .termed the small molar or bicuspid teeth ( molares anteriores , s. minores , s. bicuspidati) , and the others, which are larger, the great molar or multicuspid ( molares posteriores, s. majores, s. multicuspidali). 3d. By their triturating surface, which is less uneven. 4th. By the form of their roots. The latter are at most bicuspid, and even when they assume this form they are so only in the part farthest from their crown, that is, they never present as deep a fissure as the posterior molar teeth. In most cases they are broader from within outward than those of the incisors and the canine teeth, are terminated by a blunter summit, and their lateral grooves are more superficial. The triturating surface of the small molar teeth generally presents two eminences, one anterior and external, the other posterior and internal. From this they take their name. This arrangement is more evident in the upper jaw, because the two eminences are there separated by a deep transverse groove. In the lower jaw the eminences of the small molar teeth are, on the contrary, united by a crest, the direction of which is from without inward. This difference deserves notice, because the canine teeth of the two jaws (§ 2110) differ from each other in the. same manner. The external anterior eminence is always higher than the internal, particularly in the first small inferior molar tooth, where the internal is but slightly developed, and which, in these two respects, evidently makes the transition from the canine to the other molar teeth. But this is not true of the second small anterior molar tooth. In this we usually observe, behind the posterior eminence, a smaller and more prominent tubercle, or sometimes the posterior eminence is divided into two equal halves. At the same time the external is lower, the crown and the triturating surface are still more rounded, so that this tooth evidenth^tnakes the transition from the anterior to the posterior molar teeth ; it is also a little larger than the internal. tubercle. § 2114. The three posterior molar teeth generally present four blunt tubercles, two on the outside, and two- on the inside, which are separated by a crucial depression. But we usually observe also between the posterior two, on the edge of the triturating surface, a fifth, which Is smaller. These tubercles are also rough. The external prominences are generally the largest and most numerous, and frequently the internal tubercle is single, especially in the last two molar teeth. The last great molar tooth is usually the smallest, and the first the largest. Most generally the roots of these molar teeth present three branches, into which they frequently divide near their crown. The last, it is true, generally has but one root, but this root is never as pointed as hi the canine teeth and the incisors, and it always presents at least two very deep and very broad grooves, which indicate a tendency to divide. Sometimes also the other two great molar teeth have only two branches at their root ; but in this case one of the branches is always much broader than the other, and also presents a broad and deep groove. In some subjects this broad unmated branch bifurcates below into two small points. The branches of the roots of the molar teeth are usually more curved than the simple roots of the incisors and canine teeth ; they begin by separating from each other ; they then converge more or less at their lower extremity, where they even touch each other, and blend together at their summits, so that they intercept between them a portion of the upper maxillary bone. § 2115. The characters which we have mentioned are those by which we distinguish the teeth which remain in the jaws during most of fife. But there are other different teeth which exist but a short time, in youth, and are termed the deciduous , or milk teeth ( dentes clecidui, s. infantiles , s. lac lei), in opposition to the first, which are termed the permanent teeth {dentes permanentes). The teeth which appear at first do not continue during life ; many of them remain only till the seventh year, and at the fourteenth year all are replaced by new permanent corresponding teeth. In the first respect, we ought not to find more than two molar teeth in each half of the jaw, during the period of the deciduous teeth, whence there are only twenty deciduous teeth, while there are thirty-two permanent teeth. In respect to form, we distinguish also among the deciduous teeth, the incisors, the canine, and the molar teeth. The incisors and the canine teeth resemble the permanent teeth in form, number, and situation ; but all the deciduous teeth, and particularly the molar teeth, differ from their corresponding permanent teeth. 2d. They are less elevated. All do not present the same peculiarities in respect to size. The deciduous incisors and canine teeth are much smaller than the permanent teeth, particularly in the lower jaw. The contrary occurs in the molar teeth ; they come immediately after the canine teeth, the two small anterior molar teeth replace them, and the three molar teeth behind them are permanent. Hence the small anterior molar teeth among the permanent teeth are those which correspond to the decidu- ous molar teeth at least in respect to situation. But the latter are much larger ; they have not the same form as the small permanent molar teeth, for instead of being flattened from before backward, they are extremely broad, have a broad square crown, and also several, usually five tubercles, which are arranged around a very deep median groove. The anterior is nearly one half smaller than the posterior, although the posterior is almost as large as the largest of the permanent teeth. Besides, they have always at least two and usually three roots. Thus they correspond to the permanent small molar teeth only in number and situation, for in respect to size and form, that is, in two respects much more important than the two preceding, they are analogous to the three permanent great molar teeth. haps they differ more than any other part of the body. The history of their development presents several very curious phenomena. The most essential points to consider, are their mode of development, the period at which they appear, and their changes during life. 1st. The teeth are developed in small rounded and close sacs, which, adhere very closely to the gums. These sacs are composed of two membranes. Hunter thinks that the internal alone is vascular, while Black admits this only of the external. But we have ascertained (1) Besides the works mentioned previously, which also treat on this subject, we may consult the following : J. J. Rau, De ortu et generatione dentium, Leyden, 1694. — J. A. Ungebauer, De dcntitione secundâ ; in Haller, Coll, diss., vol. vi.— J. G. Jancke, De ossibus mandibularum puerorum septennium, Leipsic, 1751. — B. S. Albinus, Ds dentium ortu ét incremento ; in Annot. acad.. vol. ii. eh. ii., Quot dentes mutet puer, et quos, ibid., ch. iii., De dentium mutatione, ibid., ch. i. — Jourdain, Essai sur la formation des dentes comparée avec celle des os, suivi de plusieurs expériences sur les os et sur les parties qui entrent dans leur composition, Paris, 1766. — A. A. Brunner, De eruptione dentium lacteorum ; in Wasserberg, Opp. min.,fasc. I, Francfort, 1775. — M. Girardi, De re anatomicâ oratio, Parma, 1781, tab. i. — Andree, De prima puerorum dentitione, Leipsic, 1790. — Léveillé, Mémoire sur les rapports qui existent entre les premières et les secondes dents, et sur la disposition favorable de ces dernières au développement des deux mâchoires ; in the Mém. de la soc. méd. d’Emul., voL viii., Paris, 1811. — Mie), Quelques idées sur le rapport des deux dentitions et sur V accroissement de la mâchoire dans l’homme ; same journal. — Duval, Mémoire sur la position relative de l’ouverture externe du canal maxillaire, pour servir à la démonstration de l’accroissement delà mâchoire inférieure, Paris, 1812. — J. F. Meckel, Essai sur le développement des dents chez l’homme ; in the Journ. compl. des sc. méd., vol. i. p. 365. — Miel, Note sur la manière, dont les dents sortent des alvéoles et traversent les gencives ; in the Journ. de méd., vol. xxxix. p. 235. — J. E. Oudct, Observation d’une altération de la racine d’une dent canine, présentant les caractères extérieurs de la maladie des os, connue sous le nom de spinu veniosa, précédée de quelques considérations générales sur la phys. dentaire ; in the Archiv, gén. de méd., vol. i., p. 340. — Geoffroy Saint Hilaire, Système dentaire des mammifères et des oiseaux, embrassant sous de nouveaux rapports les principaux faits de l'organisation dentaires chez l'homme , Paris, 1824. from examining the human fetus, and those of animals, and Fox has also determined that these two membranes receive vessels ; the blood, however, seems to flow more abundantly to the external than to the internal. A serous fluid exists between these two layers, and the distance between them is much greater the younger the fetus is, although the layers themselves are more difficult to demonstrate than in fetuses of a certain age, on account of their extreme smallness. The external layer is more spungy, looser, thicker, and softer, than the internal. It is very distinctly continuous with the gum, whence it is easy, in the fetus, especially during the early months of pregnancy, to extract the alveoli attached to the gum. The internal layer is harder, but thinner than the external. We can demonstrate that it forms a sac entirely distinct from the external and from the gum. Its relations with the teeth are more intimate than those of the external layer, for it is the proper organ of formation. The vessels of the teeth are distributed there much more evidently, and when injections succeed, it appears entirely red. 2d. The small sacs or follicles appear very early. About the tenth week we observe very distinctly in each half of the two jaws, four, two anterior which are smaller, and two posterior which are larger ; they are arranged very compactly in pairs, but the anterior and the posterior are separated by a considerable space. At the end of the third month we find a third sac between the two pairs, and thus at this period the whole number of follicles is twenty. We generally discover -at the end of the fourth month, a sixth, situated entirely backward, and which is destined for the most anterior permanent molar teeth. 3d. At first these small sacs contain only a reddish fluid, which afterwards becomes yellowish white. After a certain time, at the fourth month of pregnancy, a small reddish and soft body rises from the base of the internal membrane ; this gradually becomes more consistent, and forms the germ or pulp of the tooth (pulpits dentis). Numerous vessels and nerves given off from the base of the inner membrane, are distributed in this small body, which seems to be enveloped by a vascular membrane, which is difficult to be detached from its own proper substance. It is at first very low, is single in every part, and terminated by a rounded summit; but it soon assumes the peculiar form of each kind of tooth, and presents its exact image, and is, in fact, the nucleus around which the tooth is molded. The latter is so developed that the loose portion appears first, and presents all the depressions and the eminences which exist upon it, while the rest is not yet formed. The teeth begin to ossify about the middle of pregnancy. On the loose face of the germ very delicate, thin, and elastic small points first appear ; these are primitively soft, but gradually become thicker and more consistent. These points are grooved and very slightly elevated. They are seen first on the most prominent part of the germ, and represent the tubercles of the future tooth. One is developed on each prominence of the pulp of the tooth ; they gradually unite with each other ; they begin to develop themselves only when a portion of the region of the germ corresponding to the crown is formed, and embrace, that part of the pulp, which they covër so closely, that some exertion is necessary to separate them. Their internal face and the external face of the germ are, however, perfectly smooth. The difficulty in separating them depends only on the exact manner in which they are fitted to the latter, since by removing one scale, we can extract the whole germ through the space thus formed. Hence, it is very probable that there is no organic attachment between the pulp and the osseous substance, so that these two parts of the tooth are united by vessels, by cellular tissue, or by some other analogous substance. But it is very curious that the germ is redder in the parts covered by the osseous substance, and that the progress of this redness is in direct ratio with that of ossification. The points soon enlarge, so that they are much thicker in the parts first developed, that is, on the triturating surface. They become much thinner posteriorly, where they are much softer. The crown gradually enlarges, and its development is finally completed. Its lower extremity contracts and becomes the neck of the tooth. The roots are prolongations of the crown, in forming which the germ follows precisely the same course as in giving rise to the latter. The number of the roots, even when the germ has formed only the crown of the tooth, is indicated by that of the distinct branches given off by its vessels. The osseous substance forms from without inward, so that the small tubercles which first appear are also the parts which always remain exposed, and the triturating surface, like the existing portion of the tooth, has already its normal volume, while it is still very thin, and its internal cavity is very large. This phenomenon demonstrates, undoubtedly, that the bony portion of the tooth is not formed by the inner face of the capsule, but by the external face of the germ, since if this were not true, the opposite arrangement would exist. This osseous portion gradually thickens, and the pulp and the dental cavity diminish in the same ratio, although we cannot suppose that the germ ossifies. Shortly after the development of the osseous points, or during their formation, the secretion of the enamel commences, by the inner face of the inner fold which surrounds the crown of the tooth, so as to be perfectly molded upon its prominences and depressions. The fluid exhaled by this membrane deposits the enamel on the osseous substance, which is so soft, and adheres so slightly to this latter in the full grown fetus, that they maybe very easily separated. It can be detached also, even in the perfect state, from the influence of certain causes, among others, by the action of heat. We discover no special gland for its secretion. It may, however, be easily separated from the prolongations of the internal layer. These prolongations which arise from the portion of the capsule attached to the germ, are at first very thick and moist ; they gradually disappear as the enamel forms, so that we may consider them as the germ of this production, and similar osseous substance of the tooth. The different kinds of teeth do not ossify after the same type in respect to time and form. The internal incisors are the first, and the posterior molar teeth the last to appear. In regard to the intermediate teeth, the deciduous teeth differ from the permanent teeth. The incisors and the canine teeth arise by one small point, and the molar teeth by several, viz. the small by two, and the large by four or five. Each point always possesses a thin triangular form on its appearance, which is the constant form of the crown of the canine tooth. • In the incisor and molar teeth these points extend, and those of the incisor teeth present two small accessory points, which do not arise by special nuclei. Among the different points of the canine teeth the external and the anterior are developed the first, and next the internal. In the large posterior molar teeth the anterior external is first seen, then the anterior internal, and the two points of the first posterior form in the same order. The different points unite according to the same law, so that judging from their development, the large molar teeth seem to be formed by two smaller teeth. The inferior arise or are developed before the. superior. The points of the anterior deciduous molar tooth are already united to the lower jaw in the full grown fetus, while this is not the case in the upper jaw. In one case where the first inferior permanent molar tooth presented five osseous points, there were only three in the superior. § 2118. When is the formation of the tooth completed? It is not certainly when it appears, since the tooth cuts through the gum before it is perfectly developed ; but we have now to inquire if the tooth ' undergoes any other internal changes after the root is perfectly formed. 2d. Probably we have less right to admit an increase in the size of the tooth than its expulsion from the alveolar process. Beside the phenomenon to which it alludes does not occur in man or in most mammalia, although observed in some of them, particularly the gnawers, (2) the teeth of which project after being extracted or cut off. 3d. The union of fractures of the teeth does not prove that their substance is continually reproduced, but only that in some cases the germ of the tooth can restore a fractured part by a process analogous to that, when at the commencement it secretes the osseous substance in every part. 5th. The duration of the enamel depends on its solidity. Thus the arguments in support of the continual formation of the teeth in general, and particularly of the enamel, are by no means conclusive. On the contrary the second fact contradicts it. Beside the mode in which the enamel is developed does not, admit this theory. externally. During this period we find in the place afterward occupied by them, a very hard and in fact a cartilaginous mass, which projects and presents numerous grooves some lines deep and entirely different from the gum ; this arises above the surface of the alveolar edges and fulfills the function of the teeth, that is, it serves principally to retain the nipple. This substance may be called the dental cartilage ( cartilago dentulis). It is worthy of notice as analogous to the horny beak of birds and reptiles. It disappears as the teeth are developed and perforate the gum. We discover in this substance, particularly in the region of the molar teeth and on its inner and concave side, several follicles of different sizes, containing a shining and yellowish substance ; these are at most but half a line in diameter, and apparently have no external orifice. Serres first mentions these follicles. (3) He thinks that they soften the gum of the child before the teeth appear, and afterwards secrete the tartar of the teeth. We however have never observed them until the period when the teeth appear, so that hitherto we have considered (2) Lavaçna, Osservaz. sulla carie dei dcnti, Genoa, 1812. — Ondet, Expériences sur V accroissement continu et la reproduction des dents chez les lapins , considérées sous le rapport de leur application à l'étude. de l’organisation des dents humaines ; in the Journ. dephys, expér., vol. iv., p. 70. from abscesses. § 2120. The triturating surface of the permanent teeth, like that of the deciduous teeth, changes more or less during life. The enamel is gradually used by friction so that the osseous substance is exposed, and the triturating substance, formed at first entirely of enamel, presents only a layer of osseous substance when the cutting edges and the pointed summits of the crowns are blunted. When the tooth is still more worn, so that the osseous substance is destroyed to the dental cavity and the latter is open, there is generally formed in the same proportion at the summit of this cavity a brownish substance resembling bone, but a little softer, which closes the opening and protects the parts within the cavity.(l) These phenomena can also be adduced against' the opinion of those who assert the continual reproduction of the enamel. Nutrition however gradually declines in the teeth, and their nutritious foramina are finally obliterated. Being retained in the alveolar processes by no organic attachment, they become loose and fall out. The alveolar processes collapse and the alveolar edge entirely disappears after the gum has closed the alveolar openings. b. Special remarks. § 2121. The different kinds of teeth do not pass through the different periods generally mentioned in the same time, but very irregularly and more or less in succession. We may mention generally : 1st. That they pass through the different periods after the same law, so that the germ of the tooth in which the follicle first appears is also the fust to be developed and ossified. 1. Deciduous teeth. § 2122. The deciduous teeth, in accordance with the first law, appear sooner than the permanent teeth. The period at which their follicles are developed and the order in which these latter are seen have already been mentioned above. The two internal follicles are those of the incisor teeth, and the external those of the molar teeth ; the fifth intermediate is that of the canine tooth. Ossification begins at the fifth month in the inner incisor teeth, a little sooner in the lower than in the upper. Next comes the external incisor tooth,' then the anterior molar tooth. About the end of the fifth month we find osseous substance in these three teeth, while only the germ exists in the other two. We have as yet been unable, to determine whether the canine or the posterior molar tooth is ossified first, because, except in one instance, we have always found these teeth with or without traces of the osseous germ at the same time. Probably, however, ossification commences first in the former, not only because we have once found in it an osseous germ, while there was none in the posterior molar tooth, but because its osseous nucleus has always seemed to us more extensive than that of the latter, and finally because it is cut first. But these three reasons, particularly the last two, do not establish our opinion with certainty. teeth are not always exactly the same. Hunter(2) and Rudolphi(3) think that the incisors are composed of three pieces, a central and two lateral pieces, which are smaller. The canine teeth arise by a single osseous germ according to Hunter ; but Rudolphi thinks by two lateral halves. Both admit that the anterior molar tooth is formed of an anterior portion and of one or two posterior pieces, and that the posterior is formed by an anterior germ and several posterior nuclei. Hunter however is very brief on this subject, although he seems to speak from observation. Rudolphi’s assertions are grounded, not on researches in regard to the development of the teeth in the fetus, but upon chemical experiments, having for their object the action of the acids on perfect teeth, which action reduces them to the number of pieces mentioned by this physiologist. Numerous observations on the fetus have convinced us that the canine and the incisor teeth are developed by a single germ, which arises at the centre and gradually extends to the sides. We cannot then consider as natural, conclusions drawn from the action of acids on perfect teeth; and farther, because other writers, as Àlbinus,(4) and Blake, (5) formally assert that the incisor and the canine teeth are developed by one nucleus of ossification. But the molar teeth in fact arise by several ment of a single incisor or canine tooth. First the anterior piece, which is the largest, appears ; this corresponds peculiarly to the incisors, and is narrower according to its height than it is afterwards. Next is seen the posterior piece, which is much smaller ; it igradually extends and unites to the other directly or on one of the two sides by a third which is developed at a later period. The second molar tooth arises by several pieces, at least three and generally four in number, an anterior, two lateral, and a posterior. The anterior piece is always larger than the others. molar tooth, are usually fused at birth. About this period the development of the first and second incisor tooth is nearly equally advanced in regard to the whole crown. Next comes the anterior molar tooth, the crown of which has not yet however acquired all its height. The third is the canine tooth. The most imperfect is the posterior molar tooth, the very thin crown of which presents in one or more points considerable spaces in its central portion, and a piece which is entirely distinct from the others. The posterior molar teeth of the lower jaw not unfrequently form a single piece in the full grown fetus. Beside the spaces and the separation mentioned disappear in the two jaws in the first few months after birth. The cutting of the deciduous teeth usually commences at the beginning of the seventh month after birth. The lower internal incisors are generally first seen ; some weeks after, the upper internal incisors are cut ; one or two months afterward, the upper and lower external incisors ; at the end of the first year, the lower anterior molar teeth ; some time afterward, the upper anterior molar teeth ; at the age of eighteen months the inferior, and soon after the superior canine teeth ; toward the end of the second year, the posterior molar teeth : so that at the age of three years all the deciduous teeth are seen. The deciduous teeth receive a distinct artery, which comes from the dental artery, and which passes through a canal in the jaw, into which it enters through a special foramen.(l) 2. Permanent teeth. § 2123. The permanent teeth are developed and appear nearly in the same order as the deciduous teeth. They however pass through their periods much more slowly. form till the commencement of the eighth month ; next that of the Canine, and next that of the middle great molar tooth. That of the anterior small molar tooth forms some months after birth, rarely betöre the seventh or eighth. Next appears that of the posterior small molar tooth, and usually at four years of age that of the third great molar tooth, which is situated the most posteriorly. The osseous germs are visible nearly at the same time as the follicles. Ossification commences in the anterior great molar tooth. Usually the external anterior point of this tooth presents at the end of the last month, of pregnancy, a small osseous piece, to which four or five others are gradually attached separately ; these do not unite till the end of the first year. We however have sometimes found in a very large full grown fetus five points, in fact entirely distinct from each other, the posterior of which was still very small. All the permanent teeth have not the same situation in respect to the deciduous teeth. The three posterior molar teeth are situated on the same range as these latter, but farther outward, while those which should be properly called the replacing teeth are included between them and the posterior wall of the alveolar processes, the incisors, the canine and the molar teeth, behind those to which they correspond. The follicles of the permanent teeth are at first contained in the same alveolar processes as the old teeth. The manner in which they are developed is very curious. They leave the upper and posterior part of the dental follicles already existing, so that they may be considered to a certain extent as arising from these latter by gemmation. They first rest directly on them, and even afterwards when they are elongated they communicate with them by long and thin cords. Our observations, however, have established that this communication is only between the external layers of the dental follicles, that the internal layers are much more essential, and entirely distract from each other, so that the new internal dental sac is developed in the old, between it and the external layer, although their cavities are unconnected. If they communicate, it must have been at a very remote period, since we have never been able to discover it even on examining the follicles of the permanent teeth when they first appear. The new sacs are gradually separated from the old by the formation of new alveolar cavities. These cavities seem at first slight depressions in the posterior wall of the old ; these depressions, like the follicles, are much shorter than these latter, and extend much farther beyond the alveolar edge than those which existed previously. A septum gradually arises from the base of the alveolar processes, and goes towards its orifice. The two alveolar processes, however, continue to communicate by a considerable opening, through which passes the cord which unites the two sacs. The elongation and the thinness of this cord depend on the increase in the height of the jaws. The openings between the incisors and the canine teeth are visible on the posterior face of the jaws. That of the internal incisor tooth corresponds to the cavity of the deciduous internal incisor tooth. That of the external is situated between the cavity of the deciduous external incisor tooth and that of the deciduous canine tooth. That of the canine tooth is situated behind the cavity of the deciduous canine tooth. The communications of the anterior molar teeth with the cavities of the deciduous molar teeth, are not visible externally, according to several anatomists,(l) but exist at the bottom of those latter; we, however, have observed that they are situated like the first, on the inside, and behind the alveolar opening of the deciduous tooth, and that they are generally narrower than the others.(2) The follicles of the second and third permanent molar teeth emerge in the same manner, the first on the outside of the deciduous molar tooth, the other afterward, on the outside of the second. The foramina of communication between their cavities are situated at the upper part of the septum which separates them. As the jaw and the deciduous teeth gradually arise by the development and completion of their roots, as the permanent teeth which replace the latter do not increase proportionally in this direction, and as they are much broader than the deciduous teeth, it follows that they are situated lower, and also a little on the outside of them. The permanent internal incisor teeth are situated behind the internal and a part of the external deciduous teeth; the permanent external teeth behind these latter and the deciduous canine teeth ; finally, the anterior molar teeth behind the deciduous molar teeth and between their roots. The crowns of the latter nearly touch the roots of the permanent internal incisor teeth, and the canine teeth are on the outside of the row, more remote from the alveolar edge, and are carried farther forward than the others. § 2124. At the age of six or seven years the second dentition commences ; the deciduous teeth fall out and the permanent teeth appear. At this time the artery of the deciduous teeth and its canal disappear more or less perfectly, (3) so that the dental capsules receive no more nutritious fluid. Usually, and in fact almost always, the permanent anterior molar teeth begin to appear before the time of the second dentition, which has deceived some writers, and led them to admit twenty-four deciduous teeth. Among the teeth which alone deserve to be called permanent teeth, the inferior internal incisor teeth usually appear first. Next come the superior internal, then the external ; afterward, and usually at the age of from thirteen to fourteen years, and almost always at the same time, the canine and the middle great molar teeth appear ; finally, at a variable period, between sixteen and twenty years, and sometimes later, the last great molar teeth appear, which are hence called the wisdom teeth ( dentes sapientice). Thus, although the permanent canine teeth appear much sooner than the small molar teeth, they however normally are cut afterward, between the appearance of these latter and the posterior molar teeth, exactly as the deci- Both resemble formations which are permanent in animals. The appearance of the incisors before the others deserves notice, as it resembles the development of the intermaxillary bone, and the corresponding- middle portion of the lower jaw which exist particularly in fishes, and more or less in all animals. The earlier development of the lower represents remarkably the formation of the ruminantia, and the regular existence of the incisors and the molar teeth without the canine teeth in the rodentia. The deciduous teeth change in certain respects before falling out. Their roots disappear ; they become both shorter and thinner, so that their inner part diminishes as they terminate more or less in a point. The more or less narrow canal in which the cavity of the permanent tooth is first situated, gradually enlarges, as wTell as its orifice, as the tooth advances ; finally, the septum which seperates the alveolar process of the permanent tooth from that of the deciduous tooth, is destroyed, and the two teeth are then situated in the same cavity as they were originally, with this difference, however, that the permanent tooth, from its greater size, always penetrates partly into the alveolar process of the adjacent deciduous tooth. The destruction of the root of the deciduous tooth doubtless depends on the mechanical action of the permanent tooth upon it, in accordance with the law, that long continued pressure on a part, causes it to disappear by obstructing nutrition, or by accelerating the destructive process. This is proved not only by the disappearance of the deciduous tooth, but also by the well known fact that those temporary teeth which are not replaced by the permanent teeth, continue very long even in the adult, and sometimes even during existence^ 1) Although the tooth which continues longer than usual often finally falls out, (2) we must not conclude that the permanent teeth have no effect in the normal state independent of their influence, but only that the deciduous teeth from their primitive destination, exist so short a time that this action is not absolutely necessary to determine their decay. Finally, the continuance of the deciduous teeth even after their vessels and nerves have completely disappeared, is favored by the adhesions between their root and the inner face of the alveolar process. (3) The permanent tooth causes the decay of the deciduous tooth principally by pressing upon the vessels and nerves of this latter, and likewise its adhesions with the alveolar process, and destroying them. The destruction of the root is not indispensible, nor even constant, as the deciduous teeth are sometimes shed, preserving their roots entire. (4) This is the proximate cause of the loss of the tooth, and not, as has been asserted, the space formed by the disappearance of the septum between the alveolar processes, the only effect of which space would be to fix the tooth less firmly.(l) In fact, there is no space, since the permanent tooth, in proportion as it destroys the septum, prevents the space from forming, as it enters the alveolar process of the deciduous tooth. § 2125. From our preceding remarks it follows, that the teeth resemble the bones generally in their chemical composition and hardness. They however differ from them in these two respects : (2) Mayer and Kathoven are the first who arranged the teeth as belonging to the horny system, which has been followed by Heusinger, but opposed by Rudolphi, but very wrongly. Bonn (De contin. membran., 1763, § 1 6), Walther ( Physiologie , vol. i. p. 176), and Lavagna (loc. cit., p. 164), had already mentioned the analogy between the teeth and the hairs. This point of doctrine had been carefully developed by Lavagna, and afterwards by Heusinger. The reasons alledged by the latter are, 1st. The teeth in the different mammalia present imperceptible transitions, from those which are most similar to the bones, to the different parts of the horny system, particularly the nails, the horns, and the hairs. 2d. The teeth of several of the mammalia have a lamellar texture like the nails and the horns, and this texture, although very evident in all, sometimes seems effaced from the greater accumulation of the earthy salts. 3d. The development of the teeth is very similar to that of the nails and horns. 4th. Certain teeth are shed and reproduced, as are also the nails and the horns. 5th. The teeth are not nourished, they are formed entirely of one piece, and the substance which forms them is not renewed. These views are in part those of Coiter, Hérissant, Cuvier, and Serres. G. F. St. Hilaire has adopted them entirely. The tooth, he says, ti produced by transudation ; it is an inorganic body, anatomically speaking, a mass composed of several layers, in which there is nothing to be compared with osseous tissue. But this naturalist has extended these ideas very much by demonstrating that we must refer the beak of birds to the formation of the teeth, a curious fact, and one of the highest importance, which fully justifies the analogy established between this formation and the epidermoid tissue. He advances also another idea, which we shall mention here briefly, although connected with important physiological considerations, it is foreign to this work, viz. that if the teeth afterwards serve for mastication, it is fortunate for those animals who possess and B. ABNOnMAL STATE. §2126. The teeth not unfrequently vary from the normal state ; and most generally present anomalies in their texture. The most frequent alterations of texture are those which relate to the period of development and the order in which it occurs ; next, those which relate to the number of the teeth. Next come the anomalies in situation and direction, and finally those in form, size, and continuity of tissue. §2127. 1st. Anomalies in the development. These are the slightest. Not unfrequently all the teeth, or some of them only, appear unusually late. This is seen particularly in the last molar teeth, in regard to which we should remark, that their unusually late appearance is only ■an extension of time between their appearance and that of the other teeth, as between the appearance of these latter compared together. It is less common for all or some of the teeth to appear sooner than usual ; sometimes, however, children are born with several teeth. It is curious, although the fact agrees veiy well with the laws and the other phenomena of vegetative life, that this early development seems evidently to be favored by the longer continuance of the fetus in the uterus, since in a proportionally great number of children who had continued in the fetal state some weeks beyond the common period, teeth existed at birth. We must mention among the anomalies in the development, the continuance of the deciduous teeth beyond the usual period, which does not necessarily oppose the appearance of the permanent teeth, and causes so much irregularity in their arrangement and situation, that we are led at first view to believe the number of the teeth to be increased. But the deciduous teeth frequently remain, although the permanent teeth do not appear, and this anomaly must even be attributed to the absence of these latter. Beside these differences in the development which relate to the quantity, there are others dependent on the quality. Thus, sometimes all the lower incisor teeth appear before one of the upper is seen. It is much more rare that the superior incisors appear before the inferior, the external before the internal, the anterior molar teeth before the external incisors, and the posterior before the canine teeth.(l) The rarest case is where the canine teeth appear before the anterior molar teeth, profit by them, but that when the formations of the teeth begin to appear in the fetus, they are real organs of the fetus ; in this sense they arise, like all the organs of sense to form a termination to the circulatory system of the advanced parts of the head, tojlimit a certain number of vascular trunks. F. T. 2d. Anomalies in the number. These teeth which most frequently appear later than the common period, the posterior molar teeth, are also those which are most commonly deficient. Instances, however, are known of the deficiency of every tooth. (2) In one subject there were only four permanent teeth in each jaw. In another there was only one incisor in the upper jaw. Sometimes the teeth have been entirely deficient. (3) It is more rare to find an excess than a deficiency of teeth. This anomaly, leaving out of view that which is only apparent, and which we have just mentioned, appears principally under two different forms. Sometimes the supernumerary teeth exist simultaneously with the others; sometimes, however, they appear after them. In the first case they make part of the same range with the others ; sometimes are found out of this range, so that when several exist they form a second series. They are generally situated behind the normal teeth, that is, the same relation exists between them and these latter as between the deciduous and the permanent teeth. This anomaly varies in the same manner as that which depends on the abnormal situation of the teeth in general. The first degree of the redundancy of the teeth is the development of one or more rounded eminences on the sid'es of the crown ; hence are formed what are termed the dentes proliferi.( 4) This anomaly seems to belong almost exclusively to the molar teeth, and it is curious as it is a greater development of one of their peculiar characters, the existence of several points on their crown. The anomaly is still greater when other smaller separate teeth exist on a normal tooth, and which are seemingly formed by special germs. In the only case of this anomaly known to us, and which existed on a canine tooth, there were three accessory teeth ; these small teeth were much smaller than the normal canine teeth, but were all formed after the same type ; they rested on the base of the crown and had the same direction. (5) The supernumerary teeth are observed most frequently in the upper jaw and forward, near the canine teeth and the incisors. This peculiarity is very remarkable, since in several animals the anterior teeth are more numerous in the upper than in the lower jaw. They usually (4) Bartholin, Hist. anat. rar., ch. i., p. 49. — Serres, loc. cit., p. 160. — Linden, Medic, phys., cap. xiii., art. 3. — Oudet, Bull, de la fac. de méd., 1821, no. i., p. 369. — G. Saint Hilaire has described and figured one of these teeth ( Syst . dentaire des mammif. et des oiseaux, p. 77, pl. i., fig. 18). differ from all tlie normal teeth in form and size, being smaller and conical, sometimes bicuspid. When they occur at the posterior part of the mouth they do not resemble the wisdom teeth. Their number varies. Generally they are few, but sometimes they are many ; in one case even the whole number of teeth was seventy-two, viz. eight incisors, four canine and twenty-four molar teeth in each jaw.(l) Possibly, however, this statement is not perfectly correct, and should be considered only as an instance of the coexistence of the deciduous and permanent teeth. Sometimes also when the number T>f teeth is unusually large, this anomaty is caused by the division of one or more into several. The second mode in which the number of teeth is increased has been termed the third dentition. There is even sometimes a fourth dentition, although the instances mentioned of this are hardly credible. The principal circumstances of this remarkable phenomenon are as follow : a. The third dentition is attended with the same symptoms as those of the first and second. The new teeth are smaller than those they replace ; they are less permanent and soon decay. b. The period of their formation is not determined. If we may judge of them from some facts, they are formed before they appear : probably, however, individuals differ in this respect. decay. e. In this respect there are differences, some of which depend on the quantity, others on the quality. Usually however one or more teeth are replaced more frequently than all. The posterior molar teeth seem to be those which are renewed most frequently, and even if this be not true it is a fact that when they are replaced by others the same phenomena are presented as at the second dentition. rably : a. Situation. In this respect the teeth are rarely abnormal, and if they are situated in the range they change their place, so that this anomaly belongs to the history of the lateral inversion. Thus the canine tooth sometimes exists between the two incisors. In other cases the canine tooth is replaced by the first anterior molar tooth, and exists between it and the second.(2) Sometimes also the teeth are developed in parts of the jaws where they are not generally found. These abnormal teeth are seen most frequently in the palatine process of the upper maxillary bone, directly or at some distance behind the normal teeth. They are in the lower jaw principally situated in its angle. The narrowness of the jaw causes them to project above the others, and their direction is also less perpendicular. b. Direction. Not unfrequently the teeth are oblique, which depends particularly on the narrowness of the jaw ; but here their faces look to the sides, and their edges are turned backward and forward. They are rarely on the contrary reversed, that is, the summits of their roots look to the alveolar edge and the crowns to the opposite region of the jaw. a great many different modes. a. In regard to the xvhole tooth , this abnormal formation is indicated by the adhesion of two adjacent teeth ; this sometimes extends their whole distance, and is sometimes confined to a portion of their extent, generally to the roots.(l) times varies very much from the common form. The first great molar tooth seems particularly to have a peculiar tendency to the imperfect development of this surface ; for we have sometimes found it on each side in both jaws with a great number of small eminences, a curious analogy with the molar teeth of the hog. The rest of the crown, instead of being smooth as usual, sometimes presents rounded, transverse, and longitudinal elevations and depressions, which depend on a deficiency in the secretion of the enamel.(2) direction. Sometimes, although very rarely, the superior molar teeth have five roots, (4) and the inferior «four. (5) More frequently these latter have three. In some subjects we find two in the canine teeth and more rarely in the incisors. (6) In the abnormal direction of the roots of the teeth they are curved very much in the form of a hook, (7) or they are oblique. These two anomalies are most frequent, particularly in the great molar teeth, which they render more solid. 5th. Anomalies in size. The upper internal incisors are principally abnormal in this respect from a primitive deviation of formation, beingmuch larger than usual. But the size and mass of the teeth may also be increased or diminished from too great or too slight activity in the formative power. The roots particularly increase in size, being affected with hyperostosis. (1) Sometimes, although more rarely, the crown is unusually large. We must also mention here the formation of a bony substance in the earthy of the tooth, which sometimes adheres to the parietes and sometimes is developed in the centre of the soft pulp which fills this cavity. (2) Atrophia is the opposite of hyperostosis ; when it takes place in the crown it sometimes does not extend beyond the enamel, or at least it begins with the layer of enamel, although it extends gradually to the osseous substance. This latter is unaltered in its texture, and the cavity of the tooth is not exposed. The anterior teeth are more subject to this disease, which attacks only their anterior face and is seen particularly in scrofulous subjects. 6th. Solutions of continuity. The fractures of the teeth rarely supervene unless preceded by an alteration of texture, which renders these parts brittle. In this case, whether the scale be detached or there is simply a fissure, the solution of continuity does not close, while it is perfectly healed even when there is a loss of substance, when the tooth is perfectly healthy. The latter applies equally to transverse and longitudinal fractures. The fractures of the roots, however, alone are consolidated. Those of the crowns do not heal, which undoubtedly depends on the fact that union takes place by an exudation of osseous substance on the outer face of the germ of the tooth, in accordance with the law of the normal formation of the tooth. It appears then from this, that the external membrane, termed the periosteum of the tooth, takes no more part in the cicatrization than in the primitive formation of the tooth.(3) 1st. Caries. It is the most common. It usually proceeds from without inward, more rarely from within outward, begins by the destruction of the enamel, and seldom extends beyond the crown. It attacks the molar teeth most frequently. It is rarely or never observed at an advanced age. bones. 3d. The formation in the alveolar- processes of cysts filled with a liquid sometimes serous and sometimes thicker than serum. These cysts partially destroy the root of the tooth. II. CERVICAL AND THORACIC PORTIONS OF THE ALIMENTARY CANAL. § 2129. The cervical and thoracic portion of the alimentary canals) are much more simple than the cephalic. They include the pharynx and the esophagus. The first begins at the posterior extremity of the cavities of the mouth and nose, and is uninterruptedly continuous with the esophagus, which is connected with the stomach. I. PHARYNX. § 2130. The pharynx^ 4) extends in a straight line from the base of the skull and the fauces to the lower extremity of the larynx, or to the fifth cervical vertebra. Its mean measure is four inches long, and one in diameter at its broadest part when moderately distended. Below this point it contracts, then dilates again, becomes narrower, and is finally continuous with the esophagus. Its posterior straight face is situated directly before the five superior cervical vertebras and the anterior muscles of the neck, behind the cavity of the mouth and the larynx, between the great vascular and nervous trunks of the neck. Its upper extremity or arch ( fornix ) is united by some cellular tissue to the lower face of the body of the basilar bone and the petrous portion of the temporal bone. Some muscles to be described hereafter attach it to different parts of the head. Upward and backward are the posterior nostrils, forward the orifice of the cavity of the mouth, backward and on the sides those of the Eustachian tubes. These different openings exist at its upper part, which is divided by the soft palate to a certain extent into an anterior and a posterior passage. § 2131. It is surrounded externally by a thin layer of cellular tissue, which attaches it loosely to the adjacent parts. Below this layer is another, which is easily separated from it ; this is also cellular and is filled with fat, and intimately unites it with the subjacent muscular layer. The nervous and vascular trunks which enter into the proper membranes of the pharynx are distributed in them. §2132. The muscular tunic of the pharynx is formed principally by the three constrictor muscles (J\I. conslrictores pharyngis),(l) a superior , a middle , and an inferior. These muscles have several common characters, which are : 1st. They surround the pharynx backward and on the sides ; their lateral extremities are attached to the adjacent, hard parts before the pharynx, especially to several bones of the face and skull, to the hyoid bone and to the larynx. A. CONSTRICTOR PHARYNGIS INFERIOR. § 2133. The constrictor pharyngis inferior or the crico-thyreopharyngcus muscle arises by from two to four triangular digitations, from the cricoid and the thyroid cartilages. The lowest and smallest is attached below the crico-thyroideus muscle to the lower part of the side, and to the lower part of the posterior horn of the cricoid cartilage. The upper, the larger, is sometimes single and sometimes triple ; it arises from all the posterior part of the side of the thyroid cartilage, excepting the lower region occupied by the crico-thyroideus muscle, which is situated between it and the lowrer digitation. The fibres of this muscle proceed from all these points, divided into several fasciculi in a greater or less extent, and go toward the median line, so that the inferior are almost transverse, while the others ascend more the higher they become, and unite at angles more and more acute with those of the opposite side on the median line. § 2134. The constrictor pharyngis médius muscle (JVT. constrictor médius pharyngis, s. glosso-hyo-pharyngeus, s. kerato-chondro pharyngeus , s. cephalo-pharyngeus) is much smaller and weaker than the preceding. It arises from the hyoid bone and the tongue, generally by two heads. The inferior or posterior , the smaller, termed the hyopharyngeus muscle, comes from the posterior part of the upper edge of the great horn of the hyoid bone. The upper or anterior , which is the larger and is termed the glossochondro-pharyngeus muscle, arises from the small horn of the hyoid bone and from the base of the tongue. Its lower fibres are transverse and even convex downward ; the upper are very oblique and are generally pointed, and either alone or blended with the upper fibres of the constrictor pharyngis inferior muscle, extends as the cephalo-phamyngeus muscle ; to the basilar process of the basilar bone, and is attached to its lower face by fleshy or tendinous extremities. § 2135. The constrictor j)haryngis superior or the glosso-mylopterygo-pharyngeus muscle arises from the posterior part and the side of -the root of the tongue, from the inner face of the lower maxillary bone, near the posterior molar tooth, from the hook of the pterygoid process, and from the tendon of the peristaphylinus externus muscle, often also a little from the petrous portion of the temporal bone and from the styloid process, and blends with the posterior part of the genio-glossus and buccinator muscles, and often also with the lower portion of the stylo-pharyngeus muscle. § 2136. The stylo-pharyngeus muscle (M. stylo-phanjngeus , s. levator, s. dilator pharyngis) is large, elongated, and rounded. It arises by a broad and short tendon from the inner face and the lower edge of the styloid process of the temporal bone. Thence it goes inward and downward. It is at first separated from the constrictor pharyngis superior muscle by a greater or less quantity of fat ; it goes from above downward and from without inward, passes under the lateral part of the constrictor médius muscle, and is distributed on the lateral and posterior wall of the constrictor médius, and adheres to its vascular tunic very intimately by a dense cellular tissue. Its upper fibres curve in an arch from below upward and interlace with those of the superior constrictor. The inferior separate like a pair of forceps. Both descend to the base of the upper horn of the thyroid cartilage, and are attached to its posterior edge. thick comes next to the muscular portion. The inner tunic or the mucous membrane is very thin, smooth, and reddish white. It is uninterruptedly continuous above with that of the mouth and nose, below with that of the esophagus. II. ESOPHAGUS. § 2138. The esophagus^ 1) is that part of the alimentary canal included between the pharynx and the stomach. It is narrower 'than either, and is continuous with them at its two extremities by tunnellike portions. This canal is situated in the posterior mediastinum, and extends its whole length before the vertebral column. Its upper part corresponds directly to the anterior face of the spine from the fifth cervical vertebra and the cricoid cartilage, where it commences, to the fifth dorsal vertebra, although it frequently also inclines a little to the left. From this point to the ninth dorsal vertebra it inclines slightly to the right ; it then returns on the anterior face of the column, passes through the esophageal fissure of the diaphragm, and soon terminates at the upper or left orifice of the stomach. At its upper part it is situated behind the trachea. From the fifth dorsal vertebra it is found between the aorta on the left and the azygos vein on the right side. It is united to the adjacent parts by a very loose cellular tissue. § 2139. The esophagus is the narrowest part of the alimentary canal. Even in its greatest dilatation its diameter is not an inch. It is equally broad in every part, except at most the slightly contracted portion which passes through the diaphragm. a line in thickness. It is composed of two layers, one external longitudinal, the other internal transverse, the first of which is twice as thick as the second. The longitudinal fibres usually commence above by three fasciculi or (1) J. Bleuland, Observations anatomico-mcdicœ de sana et morbosa oesophagi structura, Leyden, 1785.— V. Malacarne, Suit' esafago , suite intestine, c sopra alcune valvulo del tubo alimentare, Padua, 1803. heads, a middle and two lateral. The middle head arises by a tendon from the centre of the posterior face of the cricoid cartilage directly below its upper edge, and expands a little in descending. The two lateral heads, which are fleshy, descend from the lower edge of the constrictor pharyngis inferior muscle. These three fasciculi unite some inches below the upper extremity to form a muscular membrane which is uniformly extended. those of this muscle. The upper are transverse ; the next are oblique from above downward and from without inward, intercross with those of the opposite side, and describe spiral lines ; the inferior, like the superior, form straight rings. This canal for about an inch at the upper ^end of the esophagus presents no circular fibres on its anterior face, and as the longitudinal fasciculi are not united in this place, the esophagus is here much less muscular and more extensible than in other parts. The cellular or vascular tunic comes next to the muscular, and is attached to it very loosely, while it adheres strongly to the internal membrane with which it forms an internal canal which is easily detached from the muscular membrane. In this tunic there are numerous muciparous glands arranged very compactly and composed of smaller granulations, which diminish in number and size as they approach the lower extremity. The inner or villous tunic is whitish, solid, and presents, on its inner face, numerous and very narrow longitudinal grooves separated by parietes. We ought not to consider it as the same with the preceding^].) Its inner face is covered with a thinner, more delicate, and moist membrane, which is evidently an epidermis, and which suddenly terminates at the lower part of the esophagus at the part where it is continuous with the stomach. The folds of this epidermis are easily separated by boiling and maceration, although it is difficult to detach it entire unless it is morbidly thicker and firmer from some pathological change. Farther the lower extremity of the esophagus is detached from above downward in one or more parts sometime after death, which undoubtedly arises from the fact that the fluid secreted by the glands of the esophagus and cardiac portion of the stpmach soften and dissolve it, and also the loose cellular tissue which unites it to the cellular tunic. (1) Scemmerring ( Eingeweidelehre , p. 216) describes these two tunics as forming but one, termed the vascular or internal glandular tunic ; he says that the inner membrane and the vascular membrane of the stomach are continuous with it. It is true that the internal membrane of the stomach is continuous with that of the esophagus, and its vascular membrane with that of this canal. Other anatomists err still" more in considering the villous tunic of the stomach and intestinal canal as a continuation of the epidermis of the esophagus. § 2140. After the food is masticated by the teeth in the cavity of the mouth, mixed with the saliva and formed into a soft mass, the muscles of the tongue, the hyoid bone, the pharynx, and the esophagus propel it successively toward the stomach ; this constitutes deglutition (deglutitio).( 1) In order to this, the mass of food is moved from before backward in the cavity of the mouth, which motion requires the close of this cavity by approximating the jaws and lips. At the same time, the tongue is moved by its muscles, so that its edges are raised and its centre is depressed, and it thus forms a kind of groove, which touching the palate makes a canal, in which the food proceeds from before backward, because there is the least resistance in this direction. When it has passed through this course, the genio-glossi and genio-hyoidei muscles, which restore the tongue to its position and carry it forward also favor ^its progress, because they thus raise the soft palate, to which motiottals'o the levator muscles of this latter contribute. When the food has arrived at this place the constrictor muscles of the pharynx contract ; at the same time the depressors of the soft palate and the stylo-glossi muscles act to raise the tongue and contract the isthmus of the fauces ; the contractions of the constrictor phauyngis superior muscle press the pharynx against the soft palate, and thus close the nasal fossæ as they had been before by raising the soft palate. The stylo-pharjmgei muscles, then the constrictors of the isthmus of the fauces, raise and dilate the pharynx, so that the food can enter there more easily. The genio-hyoidei, the mylo-hyoidei, the thyro-hyoidei and the hyoglossi muscles carry the larynx forward and upward ; this motion favors the closing of the glottis by the epiglottis, which the pressure of the food also serves to depress, so that nothing can enter the air passages. All these parts being extremely irritable act very rapidly and easily. Deglutition, which is at first voluntary, becomes involuntary in the esophagus, although this passage receives its nerves from the pneumogastric nerves. § 2141. 1st. Primitive deviations. Sometimes but rarely the pharynx and the esophagus terminate in a cul-de-sac, one at its lower the other at its upper part, from a primitive deviation of formation. In the (1) Schulze, De deglutitionis mechanismo, Halle, 1739. — F. B. Albinus, De dcglutitione, Leyden, 1740. — Wentz, De deglutitionis mechanismo, Erlangen, 1780. — P. J. Sandifort, Deglutitionis mcckanismus, vcrlicall seclionc narium , oristfaucium illustratus , Leyden, 1805. first place the cavity of the mouth also is generally at least imperfectly developed, and the lower jaw is wholly or in great part deficient. The same thing occurs when the pharynx opens in the neck by a very narrow orifice. We cannot always determine if the contractions of the esophagus, which depend on the abnormal folding of the inner membrane without any morbid change, are primitive deviations of formation, or are produced consecutively by a simple increase of this membrane. accidents frequently appear only a little while before death. 2d. Accidental deviations of formation. Dilatations of the esophagus are generally accidental.. They usually occur after contractions situated below them, and in this case they are general. More unfrequently a portion of the circumference of the canal appears dilated in a cul-de-sac. (2) In one case the pouch was certainly caused by a hernia of the internal membrane through the muscular tunic, (3) while in another this latter also contributed to it. (4) Pouches of this kind occur only at the lower extremity of the pharynx or at the commencement of the esophagus, doubtless on account of the sudden contraction of the alimentary canal in this place, and because the esophagus is less muscular there than in other parts. Ruptures of the esophagus which are sometimes transverse(5) and sometimes longitudinal, (6) are only a greater degree of the hernia of the inner membrane. They are sometimes caused by abnormal brittleness. When the contractions are permanent, they generally supervene after a morbid alteration of texture, as thickening and induration of the coats of the esophagus, so that they are rarely pure deviations of formation. Sometimes, however, they depend originally on a simple abnormal contraction of the muscular fibres, which continues even after death ; and the greater hardness in this part does not result from an alteration of texture, but only from a stronger contraction of the muscular tunic, although the continual pressure of the latter on the inner membrane may also change its texture, and excite in it inflammation, § 2142. The most common alteration in the texture of the esophagus, is an abnormal hardness, usually attended with thickening, and consequently with a greater or less contraction, or even with a total closing of it, (2) which state is termed a scirrhus, and in which the different tunics of the passage are more or less blended in a mass, sometimes homogeneous and cartilaginous, sometimes divided into several compartments by tendinous septa. Commonly then the texture of the inner face is altered. This alteration is not observed in all parts indiscriminately; it is more frequent at the upper and lower extremities of the esophagus, in the former place, on account of the sudden contraction of the pharynx ; in the latter, because the lower portion of the esophagus tends to contract, since the two orifices of the stomach are perfectly closed during digestion, so that it is very easily injured by substances passing through it. Abnormal communications between the esophagus and the adjacent parts, particularly the trachea, (3) the lungs, (4) the aorta, (5) may occur from cancer or common ulcerations. This state may also be occasioned by ulcers formed primitively in the aorta. (6) parts, which was the primitive disease. Beside the alterations of texture in the membranes mentioned, excrescences, funguses, and polypi of different kinds, are sometimes, although rarely, developed in the pharynx and the esophagus ; these arise from the inner face of this canal, (7) and usually have their roots in the mucous and vascular membranes. They are sometimes so long, that commencing near the upper extremity of the esophagus, they descend to the stomach. They are sometimes formed by fibres perpendicular to their base, (8) are sometimes lobed(9) and suppurate.(lO) § 2143. The middle region of the digestive system comprehends th ejtomacli and the small intestine , and the most important glandular organs of this system, the liver, the spleen, and the pancreas. This is the largest and the most important portion, because digestion takes place in it, for which the preceding portion only prepares, while the terminating portion serves for the expulsion of the residue. The stomach, the liver, the spleen, and the pancreas, with the commencement of the small intestine, the duodenum, into which the pancreas, the liver, and the stomach open, occupy the upper part of the abdominal cavity. They are separated from the lower, which is larger, by a large transverse fold of the peritoneum, the transverse meso-colon. It is not, however, necessary to describe the lower portion of the intestine after these glands, nor to separate the. large intestine from the small, since they are both situated in the same cavity, then texture is essentially the same, and they are uninterruptedly continuous with each other. It is customary to describe the peritoneum before mentioning the parts of the digestive system it envelops ; but as these are not the only parts covered by it, the prolongations which extend from its outer sac to the organs covered by it, cannot be clearly described until the situation and form of these organs are well known : finally, the important anomalies of this membrane, especially those which occur in hernias, being dependent on those, to which several of the parts it envelops are subject, it is better to defer the description of the peritoneum until we mention the different systems it supports. This is the method followed by Roux in the Anatomie descriptive of Bichat. § 2144. The different regions of the middle portion of the alimentary canal, doubtless differ very much in respect to their capacity ; but they are very analogous in regard to texture, in which, however, they differ on the contrary, from the upper and lower portions. The longitudinal fibres of the muscular tunic completely surround this portion of the canal ; the vessels which go to it are more numerous, and anastomose together more frequently, and finally, the inner surface of the membrane is more or less uneven, from prominences which do not exist in the other two portions. I. STOMACH. § 2145. The stomach ( ventriculus , stomachus) ,{\) the broadest part of the alimentary canal, is included between the esophagus and the duodenum. The portion of this canal in the cavity of the abdomen commences with it. The alimentary substances all fall directly within it, assimilation there commences, and they are there changed into a liquid of a peculiar character called chyme ( chymus ). A. SITUATION. § 2146. The stomach is situated at the upper part of the abdominal cavity, under the left false ribs. Sometimes, when it is much larger, it descends into the umbilical region. Its direction is oblique from above downward and from left to right. Its upper extremity touches the diaphragm ; the lower extends to near the lower edge of the left or square lobe of the liver. § 2147. The spleen is situated near its left extremity ; behind its posterior face is the pancreas, below it the transverse colon, above it the left or square lobe of the liver and the lobe of Spigel, which is embraced by its upper curve. § 2148. The stomach has the form of an elongated cone, a little curved on itself, and is somewhat similar to a bagpipe. Its right extremity is the narrowest, and its left the broadest portion. The upper or left orifice, termed also the cardiac ( ostium ventriculi sinislrum, s. superius , s. cardia ), occupies the highest part of the stomach near its left cul-de-sac. It serves as the limit between this viscus and the esophagus, which, however, are continuous with each other and separated by no prominence, so that the lower extremity of the esophagus gradually enlarges. The inferior or right orifice, termed also the pijlorus ( ostium ventriculi dextrum , s. inferius , s. pylorus, s. janitor, )( 2) is the limit between the stomach and the duodenum. Here the transition is not gradual and imperceptible as on the left side, but occurs by a prominence, termed the valve of the pylorus ( valvula pylori). two orifices. (1) Beside, tho works of Fabricius, of Aquapcndente, Glisson, and Fantoni, already cited, consult also J. D. Metzger, Ventriculus humanus anatomice et physiologies consideratus , Königsberg, 1788. The posterior and the anterior faces, when the stomach is more or less distended, are uniformly convex, but wheq the stomach is empty they are straight, flat, and in contact. The upper or small curve , the diaphragmatic edge, is situated between the right side of the upper, and the left side of the lower orifice; it is concave and much smaller than the lower, which is also called the great curve , the colic edge. When the stomach is empty, the two curves appear as more or less distinct edges, which establish a well marked separation between the two faces. But when the viscus is full, they are very rounded, and insensibly continuous with the two faces. The base, tubercle, or great cul-de-sac of the stomach, the splenic extremity ( fundus , s. saccus cœcus), is a prolongation in the form of a culde-sac which extends from right to left on leaving the left side of the upper orifice, and which proceeds about three inches beyond the insertion of the esophagus. This portion of the stomach is not much narrower than its centre. On leaving it and the caidiac orifice, the viscus slightly enlarges to a little beyond its centre from left to right. From tips latter point to the pylorus, it gradually contracts very much. When one or two inches from the pylorus, the great curve suddenly inclines inward, but immediately resumes its former direction, although it does not afterward describe so great a curve as in the rest of its course. Hence, there is a fissure, opposite which the right portion of the small curve, instead of preserving the concave form which it possessed from the cardiac orifice, becomes convex outward, although in this place there is no contraction, between which and the pylorus is a dilatation. C. DIMENSIONS. § 2149. The size of the stomach varies much in the same individuals, in the state of health at different periods ; as this viscus dilates considerably when filled with food, and contracts when empty. Its capacity is diminished particularly in the transverse direction, and often to such an extent that the stomach is smaller than the large intestine is when in its usual and moderate state of distention. Generally, when the stomach is not unusually full, it is one foot long from the base to the pylorus, three or four inches high in it highest part, and about as many broad from before backward. Its surface is about one square foot in extent. . phrenico-gastrictm), which extends on the left to the commencement of the hase, and descends on the right along most of the small curve. This ligament is attached forward and upward to the superior lumbar portion of the diaphragm. To this ligament is attached another which is much longer, the gastro-splenic ligament ( L . gastro-splenicum), which extends from the base of the stomach to the fissure of the spleen, where it is attached, and which is continuous below with the great epiploon. The stomach is united to the transverse colon bj the great epiploon, and to the liver by the small epiploon, internal prolongations of the peritoneum, which we shall describe after giving the history of this membrane. E. MEMBRANES. § 2151. The stomach is enveloped by the peritoneum in every part, excepting a narrow ring which exists along the great and small curve, and along which the blood-vessels proceed. Below this peritoneal coat, directly on its inner face, is the muscular membrane, (1) which is very strong, but stronger than in the great and the small intestine, although weaker than in the pharynx and rectum. It is about half a line thick, and its texture is more complex than in the rest of the alimentary canal, and we may, at least in some parts, demonstrate three layers. The external layer is formed of longitudinal fibres, which mostly blend with those of the esophagus and duodenum, and are uninterruptedly continuous with them. These fibres are very much developed at the upper part of the stomach, around its small curve ; they however cover all its surface. The middle layer is formed by annular fibres, representing rings, the centre of which correspond to the longitudinal axis of the stomach. They commence at the base of the stomach, and interlace with each other, proceed a little obliquely, and cover the whole stomach to the pylorus, where they are strongest. est layer. Below this layer there is a third, (2) which is very evident on the left side, and on the small curve, and which also surrounds the stomach circularly, but in an opposite direction from the preceding, that is, longitudinally. They are the continuation of the circular fibres of the esophagus, and frequently interlace with the oblique fibres. and more distinct from the internal membrane than in the esophagus. (1) D. G. Galeati, De cornea ventriculi et intestinorum tunica; in Comm. Bonort., 1745. — Bcrtin, Descr iption des plans vmsuleux dont la tunique charnue de l'estomac humain est composée , vol. ii. p. 235. but not with the inner or villous membrane. The villous membrane of the stomach is thin, soft, loose, and spungy, softer and looser, but a little thicker than the corresponding membrane of the esophagus. It usually assumes, soon after death, a yellowish, brownish, or reddish tint.(l) Not unfrequently, especially when examined shortly after 'death, it presents in a greater or less extent, especially at the base and at the small curve, a very red color, caused by a network of small vessels almost exclusively veins. We generally consider this state as the consequence of an inflammation which had affected the organ during life ; and conclude from its existence that the patient had been poisoned. But attentive examination demonstrates that it supervenes during the struggles of death, without any suspicions of such a cause, and is occasioned particularly by the sudden suspension of the circulation in the lungs. (2) When the stomach is not distended, its villous membrane, and consequently its inner face, present numerous large and small wrinkles, which are arranged very irregularly. But these wrinkles disappear when this viscus is even very moderately distended, so that when we look at the membrane with the naked eye its inner face seems smooth, although when examined with a microscope this same face seems divided by several small intermediate parietes ; which enlarge toward the pylorus and by this are still more similar to the villosities of the intestines, into numerous compartments ; these are arranged very compactly, like the cells in a bee-hive. (3) The cellules are larger but fewer in the left half of the stomach, and are separated by simple septa. In the region of the pylorus, these septa present numerous grooves which render them still more similar to the villosities of the intestines, although they are much smaller in other respects than these latter.(4) mucous membrane of the digestive canal, they have naturally considered also its normal conditions. Rousseau (Des différent aspects que présente, dans l'état sain, la membrane muqueuse gastro-intestinale ; in the Archiv, gêner, de méd., vol. vi. p. 321) has observed, that in the healthy state it is white or slightly rosy white. This primitive color varies in different parts of the alimentary canal. Thus, the mucous membrane of the pharynx is slightly rosy ; that of the esophagus is white, particularly at its lower part ; in the stomach it has a slight rosy tint as in the pharynx. This rosy color becomes less intense in its pyloric portion, changes to white in the duodenum, preserves this appearance in the rest of the small intestine, then becomes of a pale white in the cæcum, the colon, the commencement of the rectum, and resumes its slightly reddish color near the end of this last intestine. F. T. (4) E. Home has figured this (Observations on the gastric glands of the human stomach and the contraction which takes place in that viscus ; in the Phil. Irans 1817, pt. i., p. 347, pi. i, xviii, xix. cially near the two orifices, others which are larger and which lead to more or less apparent large glands. These last glands form at the union of the esophagus and stomach a very marked prominence from three to four lines broad, which separates the two cavities to a certain extent. The villous membrane of the stomach is uninterruptedly continuous with that of the esophagus and intestinal canal. But it does not seem to be connected with the epidermis of the esophagus, since we may without the least violence separate this epidermis from it and from the villous tunic of the esophagus around the cardiac orifice. Generally, in the first respect, they are thickest in those male subjects who enjoy good health, and in the second they are thicker, as is easily imagined, the less the stomach is distended. In regard to the third we may admit that the peritoneal coat is equally thick in every part, while the others are much thinner in this cul-de-sac of the stomach than in the other parts of the viscus, and are thickest near the pylorus, where they are frequently six times thicker than at the base. F. VALVE OF THE PYLORUS. § 2152. The valve of the pylorus ( valvula pylori) is formed by the circular fibres of the muscular tunic, and also by the vascular and mucous tunics of the stomach and duodenum. The first two membranes are much thicker in this place, and all three are reflected on themselves from without inward. stomach with the duodenum. A peculiar glandular substance has been mentioned as situated between the muscular and peritoneal tunics, and as forming the pylorus and determining its form-;(2) but with the utmost care in our dissections we have never been able to discover the least trace of this substance, although we always find a very thick glandular layer before the pylorus, below the muscular membrane of the duodenum. The form of the valve varies. It generally circumscribes the whole orifice of the viscus, and it is sometimes circular and sometimes more or less oval ; in the latter case its longitudinal diameter usually extends from above downward. Between this formation and the preceding there is an intermediate degree in which the valve differs considerably in its breadth, according to the different parts in which it is examined. during life the form which it has after death. We cannot determine precisely what effect a given form of the valve has even, admitting its existence and permanence during life, on the action of the valve and on the more or less closing of the pylorus by it, since it is evident that the degree of contractilitjr in the circular fibres which contribute principally to form this fold has still more influence. C. TRANSIENT MODIFICATIONS IN THE FORM AND SITUATION OF THE STOMACH. § 2153. The stomach presents regularly transient modifications in its situation, according as it does or does not contain food. These modifications correspond then to the different states of digestion. The stomach is not only smaller when perfectly empty than when it contains food, but then its form is not cylindrical. Its anterior and posterior faces touch and its two edges are distinct from each other, while when full, its edges and faces are imperceptibly continuous. A still more remarkable modification occurring during digestion, is, that the stomach is then divided into a right and a left half ; this occurs about its centre, and is more or less distinct. The left half contains the fluids and the right the solid substances, and the former pass out from them into the small intestine without proceeding necessarily or at least entirely through the right half and the pylorus.(l) The orifices of the stomach are more or less perfectly closed during digestion ; when, however, this process has continued some time the pylorus opens, and the mass contained in the stomach passes through it to descend into the duodenum, in proportion as it is digested. The situation of the stomach also changes during digestion; it turns on its axis, so that its anterior face looks more upward and the posterior downward, although this apparent change in situation depends principally on that in its form above mentioned. § 2154. The inner membrane of the stomach secretes the gastric juice ( succas gastricus), a fluid the. exact nature of which it is difficult to determine, as it is always more or less mixed with the substances It however appears to be sometimes acid and sometimes neutral in the same subject. Its base seems to be an albuminous substance very analogous to that in the saliva. (2) Perhaps its composition is not always the same, and varies from the nature of the substances which act on the inner membrane of the stomach. The action of this fluid, united perhaps with that of the bile, changes the food into a mucilaginous, gray, and thick pulp, of a disagreeable odor and taste, termed chyme ( chymus ). The nature of this pulp varies with that of the alimentary substances ; it includes more solid parts and less of salts than any other of the animal fluids. It contains much carbon and albumen, but no gelatine, at least if we may judge from some experiments. It forms gradually in the pyloric portion. (3) The formation of chyme, or the digestion in the stomach , is singularly favored by the closing of its two orifices. We must also mention among the causes which favor this process the motions of the stomach, which are at first vague and irregular, but which gradually take place about the end of chymification from the cardiac to the pyloric orifice. I. SEXUAL DIFFERENCES, §2155. It is larger, shorter, and broader in the male ; smaller, narrower, and longer in the female^. Its muscular coat, like that in the whole alimentary canal, is generally also thinner in the female.* although the experiments of Montègre tend to prove that it is not always correct. Prout asserts that the free or at least the unsaturated acid often existing in the stomach of animals is the hydrochloric, and that the salts commonly found in this viscus are the alkaline hydrochlorates (Phil, trans., 1824, p. 1); : . Children has arrived at the same result by analyzing the fluids vomited by a man during a violent attack of dyspepsia (Annals of philosophy, 1824, July). F. T. * Beside the sexual differences, Dr. S. Th. de Sœmmerring has shown that the stomach of the negro differs from that of the European, in being of a more rounded form, approaching that of the ape (Am. Med. Journal, Nov., 1828). (4) Helvetius, Observations sur la membrane interne des intestins^ grêles, appelée veloutée, sur leur membrane nerveuse, et sur leur membrane musculeuse ou charnue ; in the Mém. de Paris, 1721, p. 392-403. — C. B. Albiuus, Dcscriplio inieslinormn tenuium hominis , Leyden, 1722, 1724. mach and the large intestine. It is uninterruptedly continuous with both, although separated by two valvular folds, the pylorus and the ilieo-cœcal valve, the closing of which can perfectly insulate its cavity, which is sometimes the case. diameter in most of its extent, and hence it is cylindrical. Its whole length from the pylorus to the commencement of the colon varies much from thirteen to twenty-seven feet, although the length of the body does not differ in the same proportion. This intestine is situated in the right half of the abdomen. It describes a considerable arch, the convexity of which looks to the right and the concavity to the left. We distinguish in it three parts, a superior , which ascends obliquely from left to right and a little from before backward; a middle, oblique from right to left and descending; finally an inferior, dfjique from right to left and ascending. It is attached to the gall-bladder and lo the commencement of the transverse colon. Its upper and smallest portion is situated above, and the lower and largest, below the transverse colon. It is covered in most of its anterior face by the posterior wall of the peritoneum, which extends forward in this place to form the transverse mesocolon, surrounds it loosely, and keeps it fixed against the posterior wall of the abdominal cavity. the mesentery. The third, on the contrary, is situated on the left side of the mesentery, the upper part of which arises from it directly. It extends to the second lumbar vertebra, goes forward in the place where the upper extremity of the mesentery blends with the transverse mesocolon and opens into the jejunum. If we except its first portion, which is covered in every part by the peritoneum, the duodenum is protected by this membrane only on its anterior side ; the posterior is attached by a very loose cellular tissue to the posterior wall of the abdomen and directly to the organs situated behind it. The inferior ascending portion is situated on the right side of the vena-cava and the right renal vessels, on the left side of the aorta, behind the upper part of the root of the mesentery, the superior mesenteric artery, and the great mesaraic vein. smooth and tense. It differs from the other portions of the small intestine by its situation and the firm manner in which it is kept in place, and also by its greater extent and the less regularity of its folds. B. MEMBRANES OF THE SMALL INTESTINE. § 2159. The small intestine is covered externally in all its extent by the peritoneum, and, except the duodenum, it is attached to the lumbar portion of the vertebral column by a long fold of this membrane, termed the mesentery (raese/nterium) . is about a third of a line thick. The external or longitudinal layer, although much thinner than the internal, with which it is very intimately united and which is never entirely deficient, surrounds the canal almost entirely. The small intestine differs from the other portions of the intestinal canal principally by the arrangement of its inner or mucous membrane.(3) The principal character which distinguishes this membrane is the singular increase of its extent and the greater development of its surface, compared Avith that of the external membranes, especially the muscular and the peritoneal tunics. (2) B. S. Albinus, Diss. de arteriis et venis intesiinorum hominis, Leyden, 1736. — J. Bleuland, Vasculorum in intestinorum tenuium tunicis subtilioris anatomes opera detegendorum description Utrecht, 1797. small intestine. They have a transverse direction, and most of them occupy the whole circumference of the intestine, so that they form circles which circumscribe it. But they divide once or twice in their course, and also communicate with each other by oblique or perpendicular elevations, which generally are less prominent and much shorter than they; three or four of them always exist between each pair of valves. breadth. They are formed only by the inner membrane and by the vascular tunic of the intestine, so that they cannot move themselves, but they are floated by the motions caused by the muscular tunic in the fluids within the intestinal canal. When we cut the intestine, we observe that they are directed towards each other, so that if we immerse the organ in water they cover one another like the tiles of a roof. Hence the term valvulœ conniventes , applied to them by Kerckring ; but it is wrong to ascribe this discovery to this anatomist, from which error they have deiived the name of the valves of Kerckring ( valvulœ Kerckringii) . An artery and vein usually pass through the base of each valve. These valves delay the course of the substances in the alimentary canal; hence their greater development at the upper part of the small intestine is curious, since the fluid contained in this portion possesses the most nutritious particles. They are no less curious as a peculiar character of the human organism. Morgagni mentions their absence in some ruminantia.(l) We have also looked for them in vain in many mammalia of all orders, even among the apes: In fact several fishes present very analogous transverse valves, which are often very numerous ; but they occupy the end of the intestinal canal in these animals, and they have no villosities. They present also this character in those reptiles in which we have seen them. (2) We may then say, in order to express the preceding proposition more precisely, that man is the only being possessing both transverse folds and villosities in the small intestine, and alone presents the union of these two organic arrangements, which are found separately in other animals. In fact most mammalia and birds, as also some reptiles and fishes, present only the villosities, and but a few genera of the last two classes the transverse folds. D. VILLOSITIES. §2161. The villosities(l) are small thin prolongations, which arc generally rounded, sometimes cylindrical, sometimes conical, and terminated insensibly in a point ; finally, sometimes enlarged at their loose extremity ; they are attached to the mucous membrane ; hence, the term villous tunic ( tunica villosa ), often applied to it. The villosities cover all the inner face of the mucous membrane of the small intestine, being very compact at its upper part, while at the lower part they are more or less remote from each other. In regard to their form, some authors, as Galeali, admit that they are cylindrical, or pointed at the origin of the intestine, and conical at its termination, but this difference is not constant. We have always found on the contrary, which agrees with the observations of Hewson, that the villosities at the upper part of the canal are broader in proportion to their length, and that from their form, they resemble the valvulæ conniventes, while as those of the lower part were thinner, elongated, and even sometimes longer than the preceding. They are about one quarter of a line long. As they are arranged very compactly, and as there are about four thousand in a square inch, we may estimate their whole number as more than a million, which is very moderate. When examined by the microscope, they appear formed of a granular substance, and their surface is not perfectly smooth, although it is not indented. When the blood-vessels of the intestinal canal are injected, the villosities are not only more apparent and filled with injection, but their surface is more uneven, because a vascular net-work is developed in it. work formed by these vessels. They are then composed of cellular tissue, in which are blood-vessels and lymphatics, the parietes of which are not distinct from its substance. It has long been disputed, whether the villosities open on their surface or not 1 (1) Beside the works of Hclvcti us, Galeati, and A. Mec.kcl, consult particularly on the villosities: — J. N. Lieberkuhn, De fabricû. ct actione villorum intestinorum tenuium hominis, Leyden, 1745. — Hewson, in his Exp. inq., vol. ii. c. xii. — R. A. Hedwig, Disquisitio ampullarxim Liebcrkuhnii physica-microscopica , Leipsic, 1797. — C. A. Rudolphi, in his Abhandlungen, &c. p. 39'. Excellent observers, as Lieberkuhn, Hunter, Cruikshank, Hewson, Hedwig', and Bleuland, admit these openings, and assert they have seen them. Lieberkuhn and Bleuland think there is generally only one at the extremity of each villosity, rarely several. Others mention more, and assert they are situated in the same place. When a minute injection has raised, inflated, and rendered the villosities cylindrical, they appear spungy, and perforated at their extremity, while they remain smooth and united on the sides. We cannot consider these openings as arising from accidental ruptures, since they are empty and entirely separated from each other, and they also occur only in determinate points, while in ruptures of a part, the vessels of which are filled with injection, we should necessarily see this injection. Cruikshank and Hunter have counted twenty of these openings in the villosities, which were not injected, but only gorged with chyle. The arguments of Rudolphi who has never seen these openings, do not refute the assertions of the observers above mentioned. He does not mention Hewson at all. The diameter of the openings figured by Cruikshank and Bleuland, which seems too great to be correct, may depend on some individual peculiarity, on the state in which the activity was at the moment of death, or even on some disease, all which circumstances would render the openings more perceptible. If Hewson has not figured them in all the villosities, it may depend either on their diameter or on the situation of the villosities, and the manner in which they were lighted. In its whole length, and on all its surface, there are very numerous distinct glands, which are the smallest (G. mucosœ , s. cryptez minima ), and which cannot be seen without a microscope. (2) must necessarily exist in every org-anic or inorganic substance, possess a special organization, so that they may be compared to a certain extent with the lachrymal puncta for instance. But it is what it does not seem to be, and we cannot but apply to microscopical observations, where the illusions are so frequent and difficult to avoid the axiom, that a negative assertion does not refute a positive one, when the latter is supported by good authority. The researches of A. Meckel, the brother of the author, also favor Rudolphi’s opinion. This anatomist does not admit vessels in the villosities of the intestine, and thinks that the injection which penetrates into them, transudes through the parietes of the arterial terminations, to be distributed in the cellular tissue which forms them. Farther, he has found, contrary to the assertion of all his predecessors, that the villosities are always flattened layers, most generally turned on their axes, and often folded on each side, so as to form a semicanal or a groove, which arrangements vary infinitely, and by which he explains the different appearances described by authors before him. F. T. Others are much larger, and divided into two classes, the solitary ( G . solitariœ ) and the agglomerate (G. agminatœ). The first are termed also the glan ds of Brunner, (1) and the others the glands of ' Peyer. { 2) The glands of Brunner are seen particularly at the commencement of the small intestine, especially in the duodenum, where they appear in the form of small, flat, rounded, lenticular bodies, at most one line in diameter, situated on the posterior face of the mucous membrane, and which open into the cavity of the intestine by broad orifices. large much from the commencement to the end of the intestine. They form about thirty masses, which are generally oblong and rounded, seldom triangular or almost square, the longitudinal axis of which is parallel to that of the intestinal canal ; they are rarely more broad than long, and they do not exist on the side of the intestine corresponding to the mesentery, but on the lateral portions, particularly the anterior. They are not prominent, or at least project but little above the surface of the intestine, and they are distinguished only by the intestine being less transparent in the points they occupy. They form on the posterior face of the mucous membrane, a thin layer, which is composed of bright, transparent, rounded, and slightly depressed points, and of darker edges in the spaces between these points. are about nine lines broad. At the upper part of the ileon they are five or six inches distant from each other ; but at the lower part, and near its termination, they are almost blended with each other, and sometimes form in the loose portion of the edge of the small intestine, an almost uninterrupted layer eight inches long. § 2163. The inner membrane of the small intestine secretes the intestinal mucus ( mucus intestinalis ) and the intestinal liquid ( liquor enterions), which probably form one and the same fluid, partially favoring the assimilation of the alimentary substances by its action upon them, and also their progress by the lubricating layer on the surface of the intestine. This progress is caused by the muscular tunic, which alternately dilates and contracts from the commencement of the small intestine to its termination, so as to send forward its contents in the same direction. In passing through the small intestine, but particularly in the duodenum, and from the influence of bile, aided by that of the pancreatic juice, the chyme is separated into two portions, the chyle ( chijlus ), a whitish fluid, similar in its chemical properties to the blood and th ef cecal matter [faces). The chyle is absorbed by the villosities of the intestine, whence it passes into the lymphatic vessels, and probably also into the meseraic veins. The feces proceed into the large intestine. III. LARGE INTESTINE. § 2164. The large intestine ( intestinum crassum , s. colon ) differs from the small intestine in its situation and attachments, form, length, breadth, and the arrangement of its tunics. A. SITUATION AND ATTACHMENTS. § 2165. The large intestine describes an arch, the direction of which is from below upward, then goes transversely from right to left, and finally from above downward, begins at the lower extremity of the small intestine, and terminates at the anus. It commences at the right iliac region, but not always in the same point. This point is generally situated at the upper extremity of the anterior face of the right iliacus muscle, between this and the psoas muscle ; sometimes, also, it occurs much lower, and sometimes much higher, before the right psoas muscle. The small and the large intestine are intimately attached in this place to the iliacus muscle by a short cellular tissue, and the first is there continuous from within outward, and from below upward with the second. the more similar the arrangement to that in the fetus. At the point of union the commencement of the colon presents a prominence which extends below its terminating extremity, and is termed the cæcum , and the cœcal appendix. § 2166. The small intestine is suddenly continuous with the large, at the point mentioned, so that it enters there at an acute angle from below upward, from left to right, and from within outward, for about an inch, and there forms a prominence termed the ileo-colic valve , (1) or the valve of Bauhin [valvula ileo-colica , s. Bauhini). This valve is (1) L. Heister, De valoula coli, Altdorf, 1718. — J. N. Licberkulm, De valvulâ. coli, Leyden, 1739.— Haller, De valvula coli, Göttinnen. 1742. — J. M. Rœderer, De valvula coli, Strasburrr, 1768. composed of two layers, a superior, generally a little narrower and almost horizontal, which forms nearly a right angle with the ascending portion of the colon, and an inferior, which is broader, and describes a more acute angle with this" same portion. is the slightly contracted orifice of the small intestine. Each is formed by the inner membrane of the vascular tunic, and the circular fibres of the muscular membrane of the large and the small intestine which are turned over in this place, while the longitudinal fibres, and the peritoneal tunic, which do not fold, pass like a bridge from the loose portion of the small intestine on the large. The muscular tunics of the two intestines are united with each other at their external face by mucous tissue, and when we consider only the valve, they form its most internal part or its centre. When we carefully destroy the cellular tissue which unites them, the valve entirely disappears, the small intestine opens directly into the large by a broader orifice than the rest of its caliber, in the form of a trumpet, and then the union of the two intestines still more resembles that of the esophagus with the stomach, since in both places the line of demarkation is evidently indicated by a very evident difference in the texture of the inner membrane, by the greater size of the lower portion into which the other opens, and by its projecting above this latter, giving rise to a cul-de-sac. § 2167. In the normal state the ileo-colic valve separates the small from the large intestine, so as to allow the substances contained in the first to pass into the second, but entirely preventing them from reascending from the latter into the former. This effect depends both on the action of the muscular fibres and the form of the valve. B. CECUM AND VERMIFORM APPENDIX. § 2168. The portion of small intestine which passes beyond the colon, (§ 2166) is composed of the cæcum ( intestinum cæcum), and of the vermiform appendix (appendicula vermiformis), (1) which originally form but one, and which do not begin to be distinct until after the early years of life. § 2169. The cæcum is elongated, triangular, and as large as the rest of the colon. It extends from an inch to an inch and a half beyond the terminating portion of the small intestine. The muscular fibres in particular, are very irregular, and very much interlaced near its closed extremity. It is terminated by a blunt summit, of which the vermiform appendix is the prolongation ;(2) the latter, however, rarely leaves its centre, but arises from its left side a little posteriorly. It is (1) J. N. Lieberkuhn, De valvula coli et usu processus vermicularis , Leyden, 1739. — J. Vosse, De intestino cœco ejusque appendice vermiformi, Gottingen, 1749. — Van den Busch, Dc intestino caeca ejusque processu vermiformi, Gottingen, 1814. the narrowest part of the alimentary canal. A small fold of peritoneum unites it to the lower extremity of the mesentery, and to the spermatic vessels which are situated below it. This appendix is generally about three inches long. Excepting its orifice, which is a little broader than the rest, and tunnel-shaped, its breadth is nearly equal in every part, and is about two lines. It is terminated in a blunt summit. A transverse fold, a kind of valve, sometimes, but not always, separates it from the ccecum.(l) Near the end of the cæcum, the three bands which form the longitudinal muscular layer of the large intestine, unite to form a thinner and uniformly expanded membrane, which is extended on the vermiform appendix, where it assumes the same arrangement. § 2170. The parietes of this appendix are as thick as those of the large intestine, and its inner membrane forms, from its great number of large and extremely compact muciparous- glands, a very complex net-work, similar, although much larger than that formed by the inequalities of the inner face of the rest of the colon. the appendix. The vermiform appendix is not always situated exactly in the same place ; it sometimes descends almost entirely into the pelvis, the edge of its mesentery opposite to that which adheres to it, being loose. Sometimes it goes upward, passing under the commencement of the large intestine. Sometimes then it assumes this ascending direction in its whole extent, and sometimes its lower extremity again curves downward in a greater or less extent. C. ASCENDING COLON. § 2171. The large intestine begins with the right or ascending colon (I. colon dextrum , s. ascendens)) which is its shortest portion, ascends before the right kidney, with wrhich it is intimately united by the right lumbar meso-colon , and extends to the anterior part of the lower face of the right lobe of the liver. In this place it describes a right or an acute angle under the base of the gall-bladder, with which it has normally no connection, goes to the right, and is continuous with the transverse colon. D. TRANSVERSE COLON. § 2172. The transverse colon (colon transversmn) is attached to the posterior wall of the abdomen by a much broader fold of the peritoneum than that of- the preceding, termed the transverse meso-colon ; it is situated below the stomach, with which it is always more or less intimate- ly united by the great epiploon, and always descends more or less before the folds of the small intestine, usually to the umbilical region, sometimes even into the small pelvis. It is always much longer than the ascending colon, and sometimes very much exceeds it in size, and then describes several circumvolutions. It extends from the right to the left side. Its two extremities are intimately attached to the duodenum by the meso-colon, which is much shorter in these two parts than in its centre. On the centre of the anterior face of the right kidney, and at the lower extremity of the spleen, it is continuous with the descending colon, describing either an arch, or a more or less acute and sometimes a double angle. § 2173. The descending colon (I. colon descendens) extends from the lower extremity of the spleen to the pelvis, passing along the lower half of the anterior face of the left kidney, then the quadratus lumborum muscle, and finally the upper and inner part of the left iliacus muscle. It is continuous with the rectum before the right sacro-iliac symphasis. and below by a very large fold of the peritoneum. This lower part projects more or less forward, and to the right, and sometimes adheres to the cæcum ; it describes a curve, hence it is called the S, or sigmoid flexure of the colon ( flexura sigmoidea, s. iliaca , s. S. romanum ), F. RECTUM. § 2174. The rectum (7, rectum) is the last portion of the intestinal canal, and it opens externally by the. anus. It begins at the lower extremity of the colon, is attached to the left half of the anterior face of the sacrum in a slight portion of its upper extremity, by a short fold of the peritoneum, termed the meso-rectum , and in the rest, simply by cellular tissue ; it goes from left to right, and from above downward, so long as it is surrounded by the peritoneum, and does not begin to descend in a straight fine until this membrane leaves it. Sometimes it descends in the pelvis on the right, and not on the left side of the sacrum. In one case of this kind observed by us, the great inferior left curve or the sigmoid flexure of the colon, advanced very much toward the right, united very intimately at its centre with the commencement of the ascending colon, and was attached in this manner to the right side. Its ascending and descending portions were also attached and separated a little from each other interiorly. Below this point, the commencement of the curve and that of the rectum were also united by a fold of peritoneum, whence there was a considerable depression, which might easily receive a portion of small intestine several inches long, and thus give rise to an internal hernia. ceeds more or less the other portions. 2d. The peritoneum covers it only in its upper region ; even ihere it covers, in most of its extent, only its anterior face, and forms no epiploic appendages on its surface. (1) The recto-vesical operation for stone, introduced by SansoD, which becomes more extensively known every day (J. L. Sanson, Des moyens de parvenir à la vessie par le rectum , Paris, 1817), requires a more detailed description of the anatomical relations of the rectum. Taken as a whole, this intestine extends from the upper strait of the pelvis to the anus. Its direction is at first a little oblique from left to right, and it curves toward the lower part of the cavity of the pelvis to go from behind forward, under the bladder, to the level of the prostate gland, below which it again curves from above downward, and a little from before backward. We may then consider it formed by three pkrts separated by these two curves, and distinct in their situation and structure, and the nature and importance of their connections. The first or superior is directed from above downward, and a little obliquely froni left to right ; it extends from the end of the sigmoid flexure of the colon to the place where the intestine leaves its peritoneal envelop, and curves to go below the bladder : it forms more than half of the rectum. It is tortuous, loose, smooth, covered by the peritoneum, and attached loosely to the posterior wall of the cavity of the pelvis by a fold of this membrane. The second or central part is included between the two curves, and is about three inches long; its direction is oblique from above downward and from behind forward ; it is slightly curved in the same direction, is fixed and immovable, and constantly corresponds posteriorly to the lower part of the sacrum, the coccyx, and the base formed by the ischio-coccygei muscles : forward to the base of the bladder, from which it is separated downward and outward by the seminal vesicles and the vasa deferentia, and still lower by the prostate gland : finally, on the sides to an abundance of cellular tissue. It differs in structure and organization from the upper portion, being wholly destitute of the peritoneum, except sometimes at the highest part of its anterior face, when the bladder is considerably retracted ; its muscular coat also is much thicker, and formed of much stronger and more numerous longitudinal fibres ; it is every where surrounded by a cellular tissue, compact only below the prostate gland, loose and very abundant in the rest of the circumference of the intestine. Finally the lower portion of this latter commences below and on a level with the prostate gland, and terminates at the anus. It varies in length from one inch to an inch and a half. It is broader above than below. Its direction is oblique from above downward, and a little from before backward. Near its origin it is every where surrounded by an abundant cellular tissue, except forward, where it corresponds to the prostate gland ; in the rest of its extent it is enveloped by the sphincters. Its structure differs much from that of the other portions. In fact, when the rectum curves a second time below the prostate gland, its fleshy tunic, which is very thick, and composed of numerous longitudinal fibres, terminates suddenly; the mucous membrane alone extends to the skin, surrounded by the round muscular fibres of the sphincters, which meet and form a kind of ring, much thinner at its origin than on the side of the skin, where it becomes much thicker, and gives rise to two caudiform prolongations, of which the anterior, the longer, goes toward the bulb of the urethra, and there blends with the bulbo-cavernosus muscle, while the posterior proceeds to the coccyx. This muscular ring is covered internally by the end of the mucous tunic of the intestine, is united forward and upward to the prostate gland, and is adapted in every part to very abundant and fatty cellular tissue. Thus the upper portion of the § 2175. The large intestine is not uniformly cylindrical like the other sections of the intestinal canal, but presents numerous elevations and depressions, which render its surface uneven. In fact the longitudinal fibres are there united in three bands separated by spaces, and the muscular membrane considered generally is shorter than the inner tunics. Hence it follows, that when the cavity of the large intestine receives the residue of digestion, it forms between the three bands three series of rounded bursae which vary in size, and are termed cellules ( cellulœ , s. haustra). These bursæ are all similar but are not perfectly alike, and are no where arranged symmetrically. Their origin from the cause mentioned proved by the fact that on cutting the bands the inequalities disappear in the place corresponding to the incision, and the canal there possesses a perfectly cylindrical form. § 2177. In most of its extent, especially in its ascending and descending portions, the large intestine is covered by the peritoneum only forward and on its sides and not on its posterior face, which is attached to the adjacent parts only by very loose cellular tissue. The transverse portion, on the contrary, is every where surrounded by the peritoneum. From the loose portion of the peritoneal coat arise the epiploic appendages ( appendicces epiploicce). § 2178. The muscular membrane of the large intestine, except the rectum, is thinner even than that of the small intestine. It is composed, as in every other part, of longitudinal and of transverse fibres. rectum is movable, and covered by the peritoneum, while the middle and inferior parts, forming- together about at least four inches, arc surrounded in every part by an abundance of cellular tissue, and are attached, but have no peritoneal envelop. The longitudinal fibres distinguish the large intestine from all the other portions of the intestinal canal in this respect, that generally speaking, they are united in three bands, situated at nearly equal distances from each other, about from four to six lines broad, which gradually increase in thickness from the circumference to the centre. One of these bands is situated posteriorly, and corresponds to the point where the intestine is kept in place by the peritoneum ; the second is anterior, and proceeds in the middle portion below the insertion of the epiploon ; the third occupies the inside of the ascending and the descending portion, and the lower side of the transverse portion, where it is perfectly loose. All terminate at the vermiform process and in the longitudinal fibres of the rectum. cular tunic is considerable in the parts which correspond to them. We also find at intervals between these three bands several distinct fasciculi of longitudinal fibres ; and in subjects where the muscular system is very much developed, the large intestine is entirely surrounded by a layer of these fibres, always arranged, however, so that the intermediate fibres are much weaker than the three bands. § 2179. The mucous membrane is perfectly smooth when considered superficially, but when examined attentively we observe that it is uneven, from numerous small, rounded, oblong, compact depressions, similar to the points of pins. These depressions give it a shaggy or honey-comb appearance, as is seen on the inner face of the mucous membrane of the stomachal) The elevations between them occupy a greater space than they, and may be considered as corresponding to the villosities of the small intestine. The arrangement of the inner membrane of the two sections of the intestinal canal differs extremely at the place where they unite, and these two sections are separated by a very distinctline of demarkation, although uninterruptedly continuous with each other. We cannot determine whether the function of these depressions is to secrete, any more than the other parts. We know, however, that they are not surrounded by a substance different from that of the rest of the mucous membrane ; but this latter appears moie thin and more transparent in these points than in the intervals between them. The mucous membrane of the large intestine presents a great number of muciparous glands, which are distinct or united in pairs or in triplets, and situated near each other. These glands represent small depressions with a more or less elevated edge. They are very evident in intestines hardened by alcohol, because then the inner membrane is contracted, and assumes à brownish color. They are formed partly by the union of several of the smallest glands.(l) § 2180. The lower extremity of the rectum is subject to the influence of the will, and is moved by several muscles, the sphincters, the levatores ani , and the transversi perinei muscles. We shall describe here only the sphincters, referring the history of the others to the chapter on the genital organs, with which they are more intimately connected than with the anus. A. SPHINCTER ANI INTERNUS. § 2182. The sphincter ani internus muscle proves very evidently the origin above mentioned ; for the longitudinal fibres of the rectum are deficient from three to four lines, the circular fibres become redder and thicker, have the form of a flattened ring, which extends beyond the longitudinal fibres. This ring is three or four lines high and about two lines thick, and it is situated directly under the skin. § 2183. The sphincter ani ext emus muscle is much stronger than the preceding, and although a distinct muscle, exactly surrounds it. It is situated under the skin, to which it adheres very intimately. It is thin and flat ; its internal fibres are less arched than the external, and the anterior and the posterior unite at an acute angle. Its anterior and posterior extremities are pointed. The anterior blends with the transversus perinei muscle, and usually also in man with the posterior extremity of the bulbo-cavernosus, in the female with the constrictor vaginæ muscle. But sometimes also it terminates in the perineum, either by fleshy or by tendinous fibres, and does not extend to either of these two muscles. In the male it is more oblong, and its greatest diameter extends from before backward ; in the female it is more circular, and at its anterior part it is broader and stronger. These differences undoubtedly depend on those which exist in the two sexes in the form of the pelvis and the external organs of generation. G. FONCTIONS OF THE LARGE INTESTINE. § 2184. The large intestine absorbs the small quantity of nutritious substance still contained in its contents, and sends the rest toward the anus. In this course the feces gradually become harder and more solid. The action of the muscular membrane finally expels them, overcoming the resistance of the sphincters with or without the con» currence of the will. This expulsion always occurs periodically. § 2185. Of all the parts in the abdominal cavity the intestinal canal is formed first ; its mode of development and the changes in its situa» tion, form, and volume, present equally remarkable phenomena.(l) A. MODE OF DEVELOPMENT. § 2186. In respect to the mode of development one part is most intimately connected with the formation of the whole fetus, but particularly with that of the intestinal canal, and must consequently be mentioned first : we mean the umbilical vesicle (vtsicula intestinalis , s. umbilicalis). It is a small, more or less rounded pouch, situated between the chorion and the amnion, and is probably much larger in proportion to the fetus the more recent the period of conception. It is even greater than the fetus during the early periods of gestation, and we have reason to think that it is always formed before it. It extends first to the anterior face of the body of the fetus, which rests directly upon it. But gradually and even early in the first month of gesta- tt) C. P. Wolff, Deformations intestinorum ; in N. C. Petrop, voL xii., p. 1768. — Oken, Anatomisch-physiologische Untersuchungen , angestellt an Schweinsfötus , Schweinsembryonen und Hundsembryonen zur Losung des Problems über das Nabetblàschen, &c., in Oken and Kieser, Heytragen , Hamburgh, 1806, 1807. — J. F. Meckel, Abhandlungen aus der menschlichen und vergleichenden Anatomie , Halle, 1806. — Id., Bcyträgen zur vergleichenden Anatomie , Halle, 1808, vol. i., pt. i., no. 5. — Id., — D. Kieser, Der Ursprung des Darmkanas aus dem Nabclblàschen, Gottingen, 1810. — Hoechstetter and Emmer, Ueber das Nabclblàschen ; in Reil, Archiv, für die Physiologie , vol. x. — Fleischmann, Leichenöffnungen, Erlangen, 1815, p. i— 75. — J. F. Meckel, Sur la formation du canal intestinal dans les mammifères et en particulier dans l’homme; in the Journ. compl. du diet, des sc. méd., vol. ii., p. 119 and 289. — L. Rolando, Sur la formation du canal alimentaire et des viscères qui en dépendent ; in the Journ. compl. des sc. méd., vol. xvi., p. 53. in the second month it is on the outside of the umbilical cord. Do the parietes of the umbilical vesicle and the intestinal canal primitively communicate ? Several anatomists of great merit(l) think that this communication is demonstrated neither in ihe fetuses of the mammalia generally nor in that of man in particular. The following facts, however, render this opinion very probable : 1st. The analogy with birds, reptiles, and cartilaginous fishes, to the vitelline membrane of which the umbillical vesicle corresponds perfectly, (2) and in which it is proved that the communication in dispute exists at all periods of fetal existence. 2d. We sometimes perceive in very young fetuses a canal which goes across the umbilical sheath, from the vesicle to the abdomen, and by which we can at pleasure empty the vesicle of this fluid, and fill it again.(3) 3d. We always find in the fetus, until the commencement of the fourth month, blood vessels which go from the mesentery to the umbilical vesicle, unite first on this latter, but gradually extend only to the anterior wall of the abdomen, and finally die, and are ruptured or entirely effaced. These are the omphalomesenteric vessels (rasa omphalo-mesaraica), comprehending an artery and a vein, which arise from the mesenteric vessels. (4) ceeding along the vitelline canal. 4th. The intestines are at first very near the umbilical vesicle, and are situated out of the abdomen in the umbilical sheath, which at this period really makes part of the abdominal cavity. (5) It is not unfrequent, proportionally speaking, to find in the full grown fetus a canal which extends from the intestine to the umbilicus, which opens in this latter place, and is always attended by the omphalomesenteric vessels.(6.) It is then very probable, though not certain, from all these facts, that the umbilical vesicle and the intestinal canal originally communicate. There are, however, others which really demonstrate the existence of this communication. (2) Needham, De form, fœtu, London, 1667, p. 79. — Blumenbach, Spec. phys. comp, inter anim. cal. sang. ov. et viv., Gottingen, 1739, p. 11.— Sœmmerring-, in Haller, Grundriss der Physiologie, vol. ii., p. 799, 800. (6) We have collected, in the first volume of our Hand, der Path. Anatomie, all the known cases of this anomaly, one of which wc observed and described (Reil, Archiv, für die Physiologie , vol. ix). and extended to the intestine, and we have figured this communication as it exists in fetuses of sheep and cows,(l) since admitted by Bojanus also in the fetuses of sheep.(l) Men, however, of high authority, doubt it. Emmert, Hcechstetter, and Cuvier, assert that there is no continuity of substance between the two organs, and that the communication existing between them, is established only by the omphalo-mesenteric vessels. In fact, they admit, beside these vessels, a third filament, extended between the vesicle and the intestine, but they do not consider it as a canal of union, but only as a simple prolongation of the peritoneum. The following are the arguments in support of their opinions : 2d. The great difference between the white and thick substance of the alimentary canal, and the thin reddish membrane of the vesicle, and also the pellucid and delicate membrane which unites these two organs, and accompanies the omphalo-mesenteric vessels. (5) But we may reply to the first objection, that the phenomenon on which it rests depends perhaps on the narrowness of the canal, and also on the thinness of the vesicle, and demonstrates at most the absence of a hollow canal of communication, the admission of which i3 not absolutely necessary, since the intestinal canal of several animals is solid at intervals, in the normal state. The second objection also loses its weight, when we consider that the allantoid membrane and the urachus vary at least as much from the bladder, and we observe as great, or even greater constant differences between different parts of the same system. This remark is more reasonable, since we have found the opening of the communication greatest in sharks, where the differences between the vitelline membrane and the intestinal canal were most distinct. Farther, the differences are also considerable in the cases last mentioned. We think then that we must at present admit a continuity of substance between the umbilical vesicle and the intestinal canal, without pretending to decide if the cavities of the two organs open into each other. From the analogy of the development of the intestinal canal in the fetuses of birds, this canal is formed in the following manner. The vitelline membrane, which is at first in direct contact with the vertebral column, begins by forming a small prominence on each side, so that originally, the intestine, which has the form of a groove, opens anteriorly. (2) Sur la vésicule ombilicale du fœtus de brebis ; in the Journ. compl. du diet, des sc. méd ., vol. ii., p. 84. — Dutrochet, Recherches sur les enveloppes du fœtus ; in the Mem. de la soc. méd. d’émulation de Paris , 1816; and a note to the Réflexions du professeur Emmert sur la vésicule ombilicale , in the Journ. compl. des sc. méd,, vol. ii., p. 369. This groove gradually forms, by the increase of its parietes, from behind forward, from above downward, and from below upward, to the place where the cavity of the intestine communicates with the vitelline sac by the vitelline canal, the diameter of which always diminishes.(l) Oken’s opinion, that the intestinal canal should be considered as a kind of excrescence of the umbilical vesicle, which enters already formed into the abdomen from above and from below, is less probable, and is unsupported by facts. First, this canal is continuous with the vesicle by its anterior edge, but very probably the point to which the communication is finally confined, always corresponds to a determinate place, although it may vary in a certain extent. Two such points have been mentioned. Oken thinks it is the point of union between the large and small intestine. He considers the vermiform appendix and the cæcum as the result and the remains of this communication. (2) In this view of the subject, the umbilical vesicle in collapsing, and the intestinal canal on descending deeply into the abdomen, produce a contraction, a kind of neck, the parietes of which approach, and are finally blended. This separates the intestine from the umbilical vesicle. The canal then enters into the abdominal cavity, where the situation of the intestines, hitherto parallel, necessarily changes, so that the anterior joins the neck at an angle, and the neck becomes a prolongation of the posterior, which preserves its former direction. Hence, according to Oken, the upper intestine seems to penetrate into the lower, the angle of union becomes the ileo-ccecal valve, and the neck gives rise to the cæcum and iis vermiform appendix. But, 1st. We do not see why the contraction of the intestine, and their entrance into the abdomen, necessarily result in causing the upper part of the intestine to enter into the lower, and form a vermiform appendix. This is still less probable, inasmuch as the cæcum and the ileo-colic valve are rarely deficient in man from a primitive deviation of formation, while they are normally absent in many mammalia provided with an umbilical vesicle ; while others, in whom the cæcum is very large, have no vesicle. The great differences in the length and structure of the cæcum, render Oken’s opinion very improbable. It is even more probable, on the contrary, that the consecprence of such a formation would be a simple uninterrutped canal. (1) Wolff demonstrated long since the manner in which the intestinal canal was formed by the vitelline membrane, in birds, after very correct and careful observations, made at an useful time, that is, at a period very near its first formation. As Needham, Blumenbach, and Sœmmcrring, have demonstrated the identity of the vitelline envelop and the umbilical vesicle, Oken had no right to claim, as he has done ( Beytragen zur vergleichenden Anatomie , 1806. — Lehrbuch der Naturgeschichte, 1815, p. 3), the honor of having discovered in the envelops of the fetus of the hog, that the intestinal canal is formed from the umbilical vesicle. 2d. The cause to which Oken attributes this change does not exist; for the cæcum is formed long before the intestines pass into the abdomen, and is itself inclosed in the umbilical sheath. 3d. If the cæcum was the point where the intestine was detached from the umbilical vesicle, it would also be the most anterior part of the intestinal canal, and the nearest to the vesicle. But this never occurs, for we always find a fold of the small intestine before the vermiform appendix. Oken, it is true, has figured the contrary, according. to his idea, that in man the intestines must detach themselves from the umbilical vesicle, (1) but unfortunately this does not exist in nature. § 2188. Oken’s opinion is still less admissible, since arguments unite to render it very probable, that the communication between the intestine and the umbilical vesicle always exists in a determinate, but very different place from that mentioned by him. This place is in the small intestine, and nearer its lower than its upper extremity. abdomen, always proceed from this point. 2d. In one rare case, in a full grown fetus, monstrous from the development being arrested at several times, there w'as a real umbilical vesicle inserted in this canal. (2) 4th. We find as the normal formation in most birds, and perhaps also in some mammalia, and not unfrequentiy as an anomaly, in this part, and never in any other, in man and other mammalia, a single rounded prolongation, varying in length and breadth, and surrounded by the same membranes. This prolongation, termed the diverticulum, is evidently a trace of the primitive canal of communication ; it is frequently attended both in the fetus and adult, with the remains of the omphalo-mesenteric vessels. Very probably, there is a period in the existence of the human fetus, when a similar small tubercle exists regularly, after the umbilical vesicle is separated from the intestine. Having found a very large diverticulum attended by the omphalo-mesenteric vessels in four human fetuses three months old, which we had occasion to examine at nearly the same time, we have reason to think that the appendix continues regularly until this period, that is, long after the intestinal canal ha3 entered the abdomen. (3) But we now renounce this opinion, although it has been refuted by no one. If a diverticulum really exist for some time as a normal formation, it disappears long before the end of the third month of gestation, since we have seen the cæcum in the seventh week, although there was no trace of a diverticulum; whence it follows, that the omplialo-mesenteiic vessels continue much longer than it. But this circumstance does not prove that the diverticulum never exists normally, or that Oken’s opinion of the cæcum is correct. the part where the large intestine unites with the small. These different arguments seem to us to render the insertion of the umbilical vessels on the ileon much more probable than that of this organ, in the point mentioned by Oken. The diverticulum sometimes found, depends either on an abnormal want of energy in the formative power, or on the fact, that the neck of the umbilical vesicle, which perhaps commonly dies on the surface of the intestine, does not then disappear except in a greater or less extent. Although these arguments were published long since, Oken still continues to maintain that the cæcum is the part where the intestinal canal is detached from the umbilical vesicle,(l) and he lays it down as a principle either to oppose us, or to support his opinion: 1st, that there is never but one cæcum ; 2d, that the cæcums of birds do not deserve this name, and are only appendages of the bladder ; 3d, that the cæcum exists in all mammalia, and in all birds and fishes who lay large eggs, while it is so small as to be invisible in a very few of these animals, the eggs of which are small ;(2) 4th, that this organ is the old vitelline canal. As these assertions are published in an elementary work, they deserve to be examined, although it is easily seen that they are totally unfounded. In establishing his four laws, Oken has forgotten, 1st, of those mammalia which possess two cæcums, as the dama and the phascolomys ; 2d, the coexistence of the canal of the .umbilical vesicle, the diverticulum, and the cæcum, in the mammalia and birds ; 3d, the perfect resemblance in the mammalia and birds, in the relations between the cæcums, the vitelline canal, the diverticulum, and the rest of the intestinal canal, since the cæcums always exist on the limit between the large and the small intestine, while this is never true of the canal and the diverticulum ; 4th, the absolute want of facts, establishing that the intestinal canal unites with the vesicle by the cæcum, while there are a great number proving that it always occurs near the lower part of the small intestine ; 5th, the fact that the volume has no effect on the deficiency of the large or small size, and the other conditions of the cæcum, since it is very large in most mammalia, and is entirely deficient in many birds. Even when we admit that the diverticulum of birds is the cæcum, which, however, is impossible, his third law would still be refuted. His third remark, “ that the cæcum exists in all mam- to be valid : for 1st. Comparative anatomy demonstrates most positively, that the cæcums of fishes are pancreatic glands, and no one has hitherto attempted to compare them to the vitelline membrane, which also exists in these animals. large intestine, and the vitelline canal at the end of the small intestine. 3d. The vitelline canal is broadly open in the fetus, and exists at the same time as the cæcum, and is entirely separate from it. This latter continues during life, while the canal entirely disappears. § 2189. The situation of the intestinal canal varies at different periods, as one may conclude from the details already mentioned. Although it forms on the anterior face of the vertebral column, it is, however, generally further from it in most of its extent, during the early periods of existence than subsequently. At first only a small portion of its upper and lower extremities exist in the proper abdominal cavity ; all the rest is inclosed in the umbilical sheath, which for this or for other reasons, is then extremely large, and should be considered as a prolongation of the abdomen. At first the upper and lower extremities of the intestinal canal extend in a straight line, side by side, and describe an angle to communicate together; but gradually, at the seventh week of gestation, they proceed backward, begin to become tortuous, and reunite in a fold before the umbilical opening, Only the small intestine is tortuous, the large intestine is perfectly straight, and its blunt extremity, the cæcum, goes forward, but always far behind the anterior extremity of the small intestine. intestine is the last to proceed. At this period, and sometime after, the canal, especially the large intestine, varies as much as before from the arrangement it will afterwards normally possess. In fact, the large intestine is not formed of three portions, two lateral, which are perpendicular, and a middle transverse portion, the right of which is attached to the organs behind it only by a short fold of the peritoneum ; but it is formed at first by a single perpendicular portion, attached by a long mesentery, to the centre of the posterior wall of the abdomen. This portion is gradually reflected from right to left at its summit ; it then descends on the right, so that the union of the great and small intestine does not correspond to the right lumbar region until toward the end of the fourth month. For a long time, and until birth, the descending colon describes in the left iliac region, a greater curve than it does in the adult, which undoubtedly depends on the narrowness of the pelvis. The situation of the stomach differs primitively from that assumed by it in the adult, as it is at first almost perpendicular. The duodenum is detached from it, and goes directly downward and forward without any curve. When the liver diminishes in size, and the intestines enter the abdomen, the stomach and the duodenum gradually change their situation, and assume that which they afterward retain. § 2190. The intestinal canal is much shorter and narrower the younger the fetus is. At first it is no longer than the vertebral column, on the anterior face of which it is developed. It then becomes more extensive, and extends always in a straight line into the umbilical sheath, but when it becomes longer, it is tortuous, being situated in a narrow space. The small is much broader in proportion to the large intestine, the younger the fetus is. In this respect, the relation between them is opposite to that which exists in the adult, for the small intestine, for a long time, is much greater than the large, and even in the full grown fetus the latter is frequently not at all or but little broader than it. On the other hand, the large intestine is much longer in proportion to the small, the younger the fetus is. This difference undoubtedly depends on the fact, that the small intestine is much shorter in proportion to the body in the early periods than in the adult. The cæcum and the vermiform process are at first very small, but soon increase considerably, so that they are proportionally much larger and broader than they are subsequently. They are not originally separated in the same manner as in the adult; the cæcum is not enlarged before it is continuous with its appendix; the latter is not as narrow, but represents the extremity of the large intestine, which is extended in a cul-de-sac above the ileon, gradually contracting a little on itself. As the cæcum first appears in man, the mammalia, and birds, as a small tubercle, which gradually enlarges, and of which there is not the least trace at first, this circumstance alone demonstrates that it is not formed in the manner mentioned by Oken, but by an enlargement of the large' intestine. Before it appears, there is no mark of difference between the large and the small intestine. The ileo-colic valve is at first imperfect and very small ; it however begins to appear at the third month of gestation, and it is perfectly developed in the full grown fetus. following remarks : 1st. The stomach is at first much longer and more rounded than when the development is completed. The great cul-de-sac does not exist originally, and it afterwards is larger than in the adult. 2d. The outer face of the large intestine is perfectly smooth until toward the end of the fifth month. The enlargements, which are the sources of its great size, appear first in the transverse colon. relative to the development of the organ. 1st. It is more uniform in the different regions of the intestinal canal during the early periods of life than subsequently. Of this we may be easily convinced by examining the valvules or the villosities. а. The villosities do not appear before the third month of gestation. At this time they are seen first along the whole intestinal canal, in the form of longitudinal folds, the surface of which is indented, and which, like the indentations, gradually increase in number. Such is the origin of the villosities. When they are developed in this manner, they exist also in the large intestine till the seventh month of gestation, although their length is less at three months than in the small intestine, and it diminishes, as well as their number, from month to month, in which respect, the two regions of the intestinal canal are at first perfectly similar. occurs in animals. 2d. The inner membrane of the stomach is thicker, and more easily separated from the others in the early periods of fetal existence than subsequently ; it is less easy to insulate it entirely in the form of a perfect sac. the class of those which affect the quantity. Among those of the first class, which essentially consist in an imperfect development of the formative power, or a continuance in the peculiar type of the fetus, may be arranged the following, some of which certainly belong to this class, and others may probably be arranged in it. 1st. Absence. This deviation of formation relates principally : a To the stomach, especially in acephalia vera, where the intestinal canal generally terminates in a cul-de-sac at its upper part, and is seldom enlarged. Sometimes a portion of the stomach also is deficient, particularly the pyloric valve, which is wholly or partially absent.(2) b. To the smalt intestine. It is deficient, wholly or partially, in acephalia vera, in which we often observe that the large intestine, or only the lower part of the small intestine exists. grees, which are commonly attended with an imperforate anus, (1) A. Monro, The morbid anatomy of the human gullet, stomach, and intestines , Edinburgh, 1811. — A. D. Stone, A practical treatise on the diseases of the stomach, and of digestion. London, 1816. — T. A. Hare, View of the structure, functions, and disorders of the stomach and alimentary organs of the human body, London, 1821. — G. Law, Observations on derangements of the digestive organs, and some views of their connection with local complaints , Edinburgh, 1821. — Scoutetten, De l’anatomie pathologique en général et de celle du canal digestif en particulier, Paris, Very rarely the large intestine is entirely deficient, existing only as a small appendix in the form of a cul-de-sac of the small intestine. Next in respect to frequency, come those cases, in which a small portion of the large intestine is deficient, so that the communication between the large and small intestine is uninterrupted; finally, that where the large intestine is developed to the entrance of the pelvis, but where there is no rectum. Sometimes the rectum partially exists, but it terminates in a cul-de-sac, and the space between it and the lower extremity of the colon is also closed in a cul-de-sac. In this case the rectum sometimes opens into the vagina ( aircsia vaginalis ), the bladder (a. vesicalis),{ 1) or the urethra (a. urethralis), so that a real cloaca is at the same time formed. 2d. Diminution in diameter. This anomaly exists in several degrees ; in the greatest degree it constitutes imperforation (a. vera). It is always attended with the absence of a part, since on account of this defect, the part existing terminates in a cul-de-sac. It occurs principally in the anus, where it varies much in degree. Sometimes the opening of the rectum is closed only by a thin membrane, sometimes this intestine is replaced entirely by cellular tissue, or by a full and solid cord. Still more rarely, the same exists in the small intestine, either in some part of its course, or at its upper extremity, or occurs in the stomach, preventing a communication with the small intestine, or finally exists in several points of the intestinal canal. Strictures^) ( a . spuria) are most frequent in the rectum and anus. They seem, however, not to be rare in the stomach, where they present remarkable peculiarities. In this case the stomach is most generally divided by a contraction near its centre, into two sacs, a right, narrower and more elongated — a left, larger and more rounded. The upper part of the left sac is usually not concave, but very convex, and the form of the two curves, particularly the inferior, are very much enlarged, the second presenting a deep groove. The esophagus is always inserted at the usual place, and the cul-de-sac is never enlarged. The degree of contraction varies much, from half an inch to five inches, judging from the five cases now before us ; but the right half of the viscus preserves its normal direction. However, in one case we saw it turned on its axis, so that the convexity looked upward and forward, (1) Cavenne, Observation d’une imperforation de Vanus , avec ouverture de l’intestin dans la vessie ; in the Archiv, gêner, de méd., vol. v. p. 63. — J. G. Hasselmann, De ani intestinirumque atresia, Utrecht, 1819. the right end of cardiac half. More rarely the stomach is divided by a second contraction into three sacs, of which the third undoubtedly arises from an unusual separation of the cavity of the pylorus from the rest of the cavity of the organ. occur principally in females. When they exist, the texture of the stomach is unaltered in the contracted portion. This circumstance, however, is not sufficient to justify the opinion mentioned at the commencement of the paragraph, that this state constitutes a primitive deviation of formation, and farther, because, as we have already mentioned, the stomach contracts transiently at the same place during digestion, and causes of different kinds might render permanent an arrangement which should be transitory. The greater frequency of this anomaly in females, is equally favorable to the two opinions. We then have reason to think that the contraction in question does not always occur in the same manner, and this conjecture is rendered still more probable, as it is sometimes congenital, and attended with other deviations of formation, which mark an arrest of development^ 1) lated. We might probably mention here a valvular contraction of the left orifice of the stomach, which is very curiously attended with the absence of the pyloric valve. (2) If, however, this anomaly was not confined to a simple contraction, we ought rather to refer it to the deviations of formation dependent on an excess of the formative power. a. The absence of the base, which we have once observed in a child two months old, where the cul-de-sac of the pylorus was much larger than that of the cardia, which was hardly visible. This anomaly exists in several different degrees. Sometimes the umbilical vesicle continues beyond the usual time, and communicates with the ileon by an open canal which the omphalo-mesenteric vessels(2) attend. Sometimes only a canal exists ; it varies in length, and extends from the same point of the ileon to the umbilicus, where it opens, and the omphalo-mesenteric vessels also accompany it. (3) Finally, sometimes a greater or less prominence exists in this place, a prolongation termed the diverticulum of the ileon , this is often accompanied by the omphalo-mesenteric vessels, which float loosely at its extremity, or which are attached to the umbilicus or to another region of the intestinal canal, so as to form a plexus. These three anomalies are only different degrees of the same deviation of formation. This is proved by their appearing always in the same place, by their connections with the omphalo-mesenteric vessels, and finally, the insensible shades which each presents in respect to length and size. That they have the signification we attribute to them, is proved : 1st, by our history of the development of the intestinal canal, by their constant co-existence with the cæcum and vermiform appendix, and finally, by the fact, that they always have the character of a primitive formation. That they depend on a primitive formation, is proved by the facts, that they are always observed in the same place, that they are formed by all the membranes of the intestinal canal, and that they exist simultaneously with other primitive deviations of formation, which arise from the development being arrested, or which, at least, favor their productions. All these circumstances united,demonstrate that it is impossible to regard them purely as accidental productions, (4) and consider them as excrescences, (5) or as contractions, (6) or hernias(7) of the ileon. the diverticula of the ileon. (1) Meckel. Beyträge zur vergleichenden Anatomie , vol. i., pt. i., 1308. — Id., — Id., Handbuch der pathologischen Anatomie , vol. i. p. 553-597. — Fulling1 2 3 4 5 6 7, Diss. de diverticulo intestinali sex mensium embryonis herniam umbilicalem referente, Marburg, 1807. — Régnault, Observation d’ un cas singulier de volvulus ; in the Journ.univ. des sc. Méd., vol. ii. p. 108. — P. Rayer, Cas mortel d'entérite et de péritonite , déterminé par un diverticule de l’iléon ; in the Archiv, gén. de méd., vol. v. p. 68. a. Their inconstancy,(l) their variety, (2) while all the transitory formations do not entirely disappear when the development is regular and also the vitelline canal in birds always continues. d. The great size and thickness of their parietes, which even did a canal of the umbilical vesicle exist in the early periods of life, would indicate an excess in the formative power. (5) were brought forward, and it is easy to refute them. The first proves nothing, for several other deviations of formation, which consist essentially in the development being arrested, are still more rare than the diverticula, and disappear entirely when the development is regular. We shall mention, for instance, the permanence of the pupillary membrane, the absence of the extremities, the continuance of the arterial canal, the urachus, and the omphalo-mesenteric vessels, the fissure of the uterus. The analogy with birds, which has been adduced, is valueless, since even in several birds, as those of prey, the vitelline canal always seems to disappear entirely, and we commonly observe traces of the primitive state longer in the lower animals than in the higher classes. Against the second objection, the extreme rarity of the anomaly on which it is founded, may be adduced. Farther, we may ask, if among these extremely rare cases, there are not some false diverticula ; if in others, the diverticulum is not produced by distension ; if in others, it does not depend on the union of the intestinal canal with the umbilical vesicle at an unusual place ; finally, if the deviation of formation cannot be developed as a primitive anomaly, differently from that which commonly occurs, although it is impossible to conclude any thing from it against this latter. The third objection favors our views, and is opposed to the theory it is adduced to support ; since even where the whole body is double, some organs alone very rarely present the same tendency, for instance, a supernumerary finger or eye is not common in this case ; while, on the contrary, the imperfect formations, especially those depending on suspended development, as the fissure of the vertebral column, the skull, the palate, and the abdomen, the deviations in the formation of the heart and the intestinal canal by defect, are then very common phenomena. The fourth objection is not more valid than the other three, since the difference between the thickness of the parietes and the size of the cavity of the diverticulum, depend on the period when the development is suspended, or on other accidental circumstances, which exert their influence afterward. The oval foramen is no less an anomaly, whether it is an inch or a line in diameter, and accidental mechanical influences may sometimes enlarge it during life. c. The great size of the vermiform appendix, depending on its continuing to increase after the type of the fetus, although this anomaly may be developed at a later period. mentioned. We should probably consider as such the division of the duodenum into two canals, the existence of two vermiform appendices, doubtless, also the unusual length of the intestinal canal, instances of which are seen particularly in the large intestine, and which render it more or less tortuous, and especially render the transverse colon pendant. (1) Perhaps we must also refer to this class the real diverticula which occur in other unusual points, although we have every reason to think that they should be considered as belonging to those deviations of formation relating to the quality. § 2196. The primitive deviations of formation which concern the quality, relate to the form or situation, or to both. Among the latter, we must arrange the lateral inversions of the stomach and intestinal canal, since in this case, the parts are not only situated opposite their usual place, but also present a figure the inverse of that they normally possess. The form of the stomach or the intestinal canal, rarely presents primitive deviations of formation in respect to quantity ; and the examples known of them may all be referred to anomalies in the diameter. 1st. Extent. a. Excess in extent rarely occurs in the whole abdominal portion of the alimentary canal, but it is observed in all its parts, and it is produced by very different causes, that is, particularly by obliteration, contrac- (1) P. Monterossi has figured a great many cases of this kind at the end of a memoir on the unusual curves of the large intestine , considered as the cause of death in new born children , in Brcra, Nuovi commentari di niedicina , 1819, vol. iv. p. 3. The abnormal distension of the vessels of the alimentary canal, which not unfrequently exists, deserves tobe mentioned here. It is most generally observed in the rectum, in the form of rounded tumors, which project into the cavity of the intestines, and are termed haemorrhoids. (2) It is generally admitted that these tumors are situated in the hæmorrhoidal veins ; doubtless also, the arteries contribute to them, although we cannot admit with Cruveilhier, that they are new formations, an accidental development of the erectile tissue. More probably, they depend in some cases on the dilatation of the small vessels, and in others, on that of the larger vessels, and in the last case, where they appear as sacs, the dilated portion is separated from the rest of the vessel. The vessels of the stomach are generally dilated in melena, and the black substance vomited, or which is found in the stomach, is blood more or less changed, which has transuded through their extremities. b. Abnormal contractions, when not primitive, are rarely confined to a simple deviation of formation. They generally succeed alterations of texture, inflammation, and its consequences, effusion, scirrhus, &c. The first commonly occurs when the alimentary canal is not distended by the causes which habitually act upon it, consequently after long fasts. The whole canal is affected. A contraction occurs also in a portion of this canal situated below a solution of continuity which entirely divided it, consequently when an artificial anus is formed after a wound or strangulated hernia. 2d. We more seldom find an increase or diminution in mass without an alteration of texture; the first occurs particularly in the muscular tunic, and supervenes when this membrane has been unusually exercised. Thus it is more rare to find the stomach dilated than very muscular in gluttons. The muscular membrane is similarly changed in a herniary portion of intestine. flesh. 3d. Situation. Deviations in situation should be referred to the chapter on hernias, since they generally occur in these affections. The small intestine is particularly liable to a change in its situation, on account of its greater mobility, its smaller size, and its situation. Next comes the stomach, which generally emerges through the linea alba or the upper part of the abdominal muscles, sometimes, however, through the umbilical ring. When abnormal openings exist in the 4 th. The principal changes in form are : a. Inversion , in which one portion of the intestine is turned, so that its inner face becomes the external, and the outer face the internal. When this change occurs at the lower part of the rectum, it is termed a prolapsus ani. In every other part it is called intussusception or invagination , because the inverted part enters that below it. The first state is more simple, since the portion of intestine which forms the prolapsus is composed of two parts, situated one on the other, the external of which is reversed and the internal is normal, while in the second case is added a third, that into which the inverted portion enters. Sometimes we find a still greater number of superimposed layers, there being two invaginations, one within the other. scend into the rectum and emerge from the anus. The most common cause of this state is the irregular action of the muscular membrane. Sometimes, however, it is caused mechanically by tumors, which force a portion of the intestinal canal downward and inward. Slight invaginations are doubtless not dangerous, and disappear of themselves ; but when they exist to a greater extent they cause inflammation and gangrene of the herniary portion, which is usually, but not always, attended with death ; sometimes, however, the gangrenous portion sloughs off, and the space is filled by adhesive inflammation. 5th. Solutions of continuity result either from mechanical influence, as the action of a cuttting instrument, a rupture, or from a previous alteration of texture, as from ulcerations. They are sometimes complete, and then affect all the tunics, sometimes confined only to the muscular and peritoneal membranes, whence results a hernia of the inner membrane, and the formation of a rounded tumor termed a false diverticulum {cl. spurium). The false differs from the true diverticulum by its rounded form, by the absence of several superimposed tunics, and finally by its occurring in every part, even in the stomach, but most frequently in the duodenum, and by the existence of several at oncc.(l) or thinness, and when occurring in a still greater extent its perforation.(l) This alteration is seen particularly in the large cul-de-sac and in the posterior wall of the stomach, and commences by the inner membrane, which always appears very red in this place. The edges of the perforation are very irregular, and differ from those of a perforation caused by an ulcer by the total absence of thickening and hardness of the edges, which are, on the contrary, very thin and soft. Sometimes this change supervenes after death ; sometimes it occurs during life, but in both cases it is caused by the action of the gastric juice on the stomach, and we may consider it as resulting from the digestion of the membranes of the stomach by this juice, which effect results when the perforation occurs during life from some change in the chemical composition of the gastric fluid. (2) quote his words. Ulcerations and perforations of the stomach vary in form, situation, and extent. They are small and circular, or large enough to introduce the hand into them. They may occur in any part of the stomach, but are seen particularly at the base of this organ, in the portion corresponding to the spleen and diaphragm. Sometimes then the food enters into the abdomen, or the thorax if the diaphragm be perforated. But most generally there is no ell'usion, the ulcerated portion of the stomach being connected with the adjacent parts. If we destroy these adhesions, which are slight, a viscous, and sometimes a fluid, flows from the stomach, which is not fetid, and sometimes has an odor like musk ; it is always brownish, and mixed with blackish flacculæ or molecules, as if finely pulverized charcoal was strewed in mucous serum. The edges are soft, broken, and sometimes surrounded with a more or less marked blackish line. In every other part the stomach preserves its usual form and consistence. It rio where presents marks of engorgement or inflammation : only the capillary plexuses of its follicular membrane seem to be more developed, especially around the perforation. Sometimes these changes form suddenly in a few hours in healthy persons ; most generally, however, after several days of sickness, and when no violent external causc'or poisoning can be suspected ( Bulletin des sciences médicales du département de l’Eure, no. 53. p. 7). Consult also on this sub ject which relates to one of the most important questions in legal medicine : Gerard, Des perforations spontanées de l’estomac , Paris, an. xii. — Morin, Considerations générales sur l'érosion, Paris, 1806. — G. Laisne, Considerations médico-légales sur les érosions et perforations spontanées de l'estomac; in the journal called Médecine légale, Paris, 1819, p. 135. — J. Cloquet, Sur les perforations intestinales; in the Nouveau journal de médecine, vol. i. p. 107. — Serres, Observation d'une perforation de V œsophage ; in the Revue médicale, vol. x. p. 166. — Id., Observations de perforations intestinales ; same journal, vol. x. p. 170. — E. Legallois, Plusieurs perforations du canal intestinal et spécialement des gros intestins, â la suite d'une affection tuberculeuse ; in the Archiv, gén. de méd., vol. vi. p. 68. — Louis, Du râmollissemcnt avec amincissement et de la destruction de la membrane muqueuse de l'estomac ; same journal, vol. v. p. 5. — Abercrombie, Observations sur l’inflammation et l'ulcération de l'estomac ; sanie journal, vol. v. p. 447. — Louis, Observations/elatives aux perforations spontanées de l’intestin grêle, dans les maladies aigues ; saine journal, vol. i. p. 17. — U. Coste, Observations sur les perforations de l'estomac; in the Journ. unie, des. sc. méd., vol. xxix. p. 257. F. T. (2) This is the opinion of Hunter. We cannot admit it. It rests on Hunter’s opinion in accordance with that of Spallanzani, in respect to the gastric juice. But it is very evident that the gastric juice does not exist, as these two physiologists have supposed, that it docs not accumulate in the stomach between meals, that it is secreted only at the moment when the viscus is filled witli food, that this secretion is caused by the impression produced by the latter, and so far from being identical, it always varies according to the nature of the substances from which the chyme is found. Besides, perforation of the stomach has never been observed, in the cases of death by starvation hitherto observed, and that cited by Ilunter should be referred In regard to the inflammation of the stomach, we ought to remark that the inner membrane of this viscus, which is the most subject to inflammation on account of the numerous vessels it receives, the formative power it possesses, its connections with the skin, and the direct effect of deleterious substances upon it, often presents, when not inflamed, a very deep red color, which depends on an accumulation of blood in the small twigs of the veins, and is observed particularly after death, from those causes which favor the stagnation of blood in these vessels by opposing its return to the heart. In inflammation of the mucous membrane, the mucus becomes thicker and firmer. At the same time the fibrin is effused on the inner face and in the substance of this membrane. The result of the first of these phenomena is, the formation of more or less thick, hollow, or solid cylinders, which pass off from the anus, and which have been wrongly considered as the membranes of the intestine. The effect of the second is, to thicken the parietes, and thus to contract the cavity of the canal. In the latter case partial adhesions sometimes, but rarely, occur, and probably arise from ulcerations. (3) and, as it were, cut. Inflammation and suppuration frequently form fistula of the amis ( fistula ani ), that is, a canal which commences on the inner face of the rectum, descends on its sides, and terminates near the anus. Like all fistulous passages, this canal is covered internally by an epidermis, similar to the mucous membranes, and is surrounded with a dense cellular tissue. (4) In dysentery, where the inflammation is situated principally in the mucous membrane of the large intestine, especially of the rectum, this membrane frequently mortifies in several parts, and black and dry eschars are formed on its surface. (2) Scoutetten, Recherches d'anatomie -pathologique, démonstrant le rapport qui existe entre l'irritation de la membrane muqueuse du canal intestinal et celle de la ■méningine ; in the Journ. univ. des sc. méd., vol. xxviii., p. 257. (4) J. Howship, Practical observations on the most common diseases of the Imecr intestines and anus , London, 1820. — C. Bell, A treatise on the diseases of the urethra, vesica urinaria, prostata, and rectum, London, 1820. — T. Copeland, Observations on the principal diseases of the rectum and anus, London, 1814. All these phenomena are usually confined to the mucous membrane. The tubercular formation, however, in which rounded, whitish, and hard masses are formed, extends from this membrane to the outer face of the organ, where it forms more or less evident prominences. This change is commonly observed inthe latter periodof tuberculous phthisis, especially in the small intestine. The ideerations thus affect all the membranes of the stomach, and then gradual^ extend from within outward. They do not necessarily result in the effusion into the abdomen of substances contained in the organ ; this is even proportionally rare on account of the adhesions with the adjacent parts, or because the opening communicates with another portion of the intestinal canal, or with the exterior, when the wall of the abdomen adheres to the diseased organ. Inflammation of the peritoneal coat of the alimentary canal is often followed by more or less general and intimate adhesions between the different parts of the passage. These adhesions are sometimes so numerous and intimate that the folds of the intestines form one mass, which cannot be separated from the surrounding substance, and represents only a canal hollowed in an amorphous mass. One of the most common alterations of texture in the intestinal canal is the scirrhous formation, which extends from the vascular tunic and the muciparous glands, where it is primitively situated, to the mucous and muscular membranes. It blends together all these tunics, and renders them thicker and harder ; they finally present a carcinomatous ulceration.(l) This alteration of structure causes a contraction of the canal, which is often very great. It is observed more particularly in the pylorus, the end of the descending colon, and the rectum, which depends perhaps only on the disposition of these parts to retain for a longer period the substances which pass through them, and are also more exposed to irritation and its consequences. But. the morbid affection extends also a greater or less distance to its primitive source, so that it sometimes attacks the whole stomach and a very great portion of the intestinal canal. Very probably we must arrange here tlae morbid alterations described by Monro, in which albumen is deposited in the vascular tunic, for all its essential characters are the same, and it differs from cancer only in its form, since it appears as small rounded bodies. (2) The fungous excrescences of the mucous membrane are much more rare. They have however been found in every part of the intestinal canal. Thus authors have described some cases of very large polypi of the stomach, one of which extended from the cardiac orifice even within the duodenum. (3) We have lately found in the cadaver of a young man frequently affected with abdominal affections, and who died of violent enteritis, two excrescences of the mucous membrane of the small intestine, one of which was about four lines in diameter, and was covered in all parts by the mucous membrane, while the other, about an inch in diameter, had destroyed this membrane, and was unattached. These excrescences are more common in the rectum(l) than in any other part. They are similar only in form, for they differ much in respect to texture ; since they are sometimes very hard and solid, sometimes spungy, and of a loose and soft tissue. The first probably belong to the class of fibro-cartilages, and the others to that of fungus hematodes. In fact, in examining the viscera of individuals who have died from a severe attack of small-pox, we have found the inner membrane of the intestinal canal very red, but have never seen in it pustules. The normal tissues are rarely formed abnormally in the intestinal canal. We must however mention here, the fatty tumors developed on the inner face of the mucous membrane, (3) the hairs which are found sometimes alone on the inner face of the intestine, (4) sometimes attended with teeth, in the. stomach, (5) the ossifications of the inner face of the intestine, (6) and finally, at least in certain cases, hemorrhoids, when they are cavernous formations. minal portion of the alimentary canal, particularly in the intestine. Those seen most frequently are the intestinal worms, which in fact are more common here than in any other part of the body. The ascaris lumbricoides, the toenia lata, s. bothryocephalus latus, and the tcenia solium, live principally in the small intestine, the trichocephalus dispar in the large intestine, and particularly in the cæcum, finally the ascaris vermieularis, oxyuris vermicularis, Bremser, in the large intestine, and particularly in the rectum. These worms exist in the stomach only accidentally, and generally even not till after death. The openings through which they sometimes pass into the peritoneal cavity are not formed by them. (1) Meckel, 'Handbuch der pathologischen Anatomic , vol. ii., pt. ii., p. 511. — Lnracine, Observation sur une tumeur fongueuse pèdCculée dans le rectum ; in the Bull, d.e la soc. méd. d’émul. , September, 1821. § 2201. The glandular organs of the abdominal portion of the digestive system, (2) termed also, together with the stomach, the chylopoietic viscera ( viscera chylopoietica ), are the liver , the pancreas , and the spleen. They are situated in the upper half of the abdomen, and are intimately connected with each other, and with the stomach and the duodenum, not only in situation but also in the vessels and nerves they receive, but even, except in the spleen, in continuity of substance. In fact they receive their vessels from the same trunk, the cceliac artery ; their nerves come from the same source, the solar plexus ; finally, the excretory canals of the liver and pancreas, which open into the duodenum, are in fact folds of the inner membrane of this intestine. § 2202. The liver (hepar, jecur),( 3) the largest gland in the body, occupies all the right hypochondriac region, the upper part of ihe epigastric region, and in the female particularly, part of the left hypochondriac region. It descends on the right side lower than on the left, (3) A. Rolfink, De hepate, Jena, 1633. — F. Glisson, Anatomia hepatis , London, 1654. — M. Malpighi, De hepate ; in the De viscerum structura, Bologna, 1666. — J. B. Bianchi, Historia hcpalica, Turin, 1711. — A. Bertrandi, De hepate et oculo, Turin, 1748. — A. Franken, Hist, hepat. anat., Leyden, 174S. — J. G. Gunz, Obs. circa hepar , Leipsic, 1748.— A. Ferrein, Sur la structure des viscères nommés glanduleux , et particulièrement sur celle des reinset du foie ; in the Mém.dc Paris , 1749, p. 709. — M. Ambodick, De hepate, Strasburg, 1775. — F. A. Walter, De structura hepalis et vesiculœ felloe ; in the Annot. acad., Berlin, 1786. — Saunders, A treatise on the structure, economy , and diseases of the liver, London, 1798. — J. M. Mappes, Disc, dc penitiori hepatis humani structura, Tubingen, 1817. — Id., Quelques considerations sur la structure du foie et du rein ; in the Journ. compl. des sc. méd., vol. xii., p. 223. — J. F. Bcltz, <lu<cdam dc hepatis dignitale, Berlin, 1822. so that it is situated obliquely from below upward, and from right to left. On the left side it terminates near the upper extremity of the spleen ; its left portion covers the stomach, the right generally the whole right kidney, but when the latter organ is situated lower than usual, only its greater upper half. B, DIMENSION AND WEIGHT. § 2203. The transverse diameter of the liver in the adult is usually from ten to twelve inches ; the antero-posterior is from six to seven inches. The gland is two inches high in its thickest portion. § 2204. The form of the liver is irregular and quadrangular. It is much thicker from one side to the other than from before backward, and is thinnest from above downward. § 2205. The liver is generally divided into two halves or lobes (loin), the right and the left, separated on the upper face by the suspensory ligament, on the anterior edge by a deep groove, and on the lower face by a deep longitudinal fissure, which extends the whole breadth of the gland. § 2206, The right lobe (/. hepatis dexter , s. major ) is about four times as large as the left (l. hepatis sinister , s. minor), and much exceeds it in all its dimensions, but particularly in its thickness. and depressions which render it very uneven. These inequalities are connected with the blood vessels, the lymphatics and the biliary vessels which enter or emerge from the liver, and correspond to the fissures ( hilus ) of the other glandular organs. The two edges of the liver, the anterior or inferior , and the posterior or superior , are generally convex, but the first is more so than the other. The anterior is thin and sharp, the posterior thick and blunt, so that the upper and lower faces gradually unite in that part, although there is a very distinct limit between them. The -left portion of the lower face of the right lobe, which is the smallest, and which occupies the centre of the lower face of the liver, considered as a whole, has the form of an H inclined from before backward, the transverse bar and the two legs of which are formed by the fissures (sulci, s. foveœ) which converge behind the lower face of the liver, between which are the elevations (lobidi). § 2207. The transverse or median fissure (sulcus intermedins, s. transversus) is situated about the centre, a little nearer the posterior than the anterior edge. We notice in it the commencement of the excretory duel of the liver, or the hepatic canal (d. hepatic us), the commencement of the arterial portion of the vena-porta and the hepatic arteries. The hepatic canal is situated entirely forward, the venaportae between an anterior and a posterior series of branches of the hepatic artery. Each of these three vessels divides into a right and a left branch ; from the hepatic artery are commonly formed two, which are entirely distinct, a right and a left. § 2208. The left longitudinal fissure ( fossa longiludinulis sinistra), which separates the right from the left lobe, extends from the anterior to the posterior edge. The left extremity of the vena-portae divides these into two halves, an. anterior, longer and deeper, and a posterior, smaller and more superficial. groove for the umbilical vein or the round ligament of the liver. Gunz has asserted, contrary to most anatomists, that this anterior half is most generally changed into a real canal, as in almost all animals, by one or more bands of the substance of the liver, which extend like a bridge from the lower face of the great lobe, to that of the small, and are sometimes also replaced by a simple prolongation of the peritoneal capsule of the gland. The posterior half of the left longitudinal fissure, which is more superficial than the anterior, especially toward the left lobe, is the fossa for the venous canal {fossa pro duc lu venoso), which is there directed from before backward, from below upward, and near its termination a little from left to right. layer of the substance of the liver, which is then very thin. § 2209. The right longitudinal fissure ( fossa longiludinalis dexlra) is much more superficial, and its anterior part, separated from the posterior by the vena-porta, differs much from this latter in form and in importance. The anterior is planer and is not covered by the peritoneum ; it receives the gall-bladder [ fossa pro vosiculd jelled). This depression is most generally indicated forward by a greater or a less groove, and sometimes it communicates near its anterior extremity with the upper face of the liver by an opening. The posterior is directed from below upward, and is continuous with the posterior edge ; it is termed the fossa of the vcna-cava {fossa venae cavœ), because it receives the upper part of the ascending vena-cava. It blends posteriorly in the blunt edge of the liver with the fissure of the venous canal. It is rarely wholly or partially changed into a canal by a band of the substance of the liver. About twenty small hepatic veins proceed from this fossa from below upward, in pairs side by side, and empty into the ascending vena-cava ; but from its upper part arise two large venous trunks, a right and a left, which terminate in the same manner. Thus the vena-cava follows, in the arrangement of its branches, the same law as the other vessels of the liver, and although the latter is a simple organ, it seems composed of two halves, a right and a left. § 2210. The portion of the lower face of the liver, situated between the two longitudinal fissures, is divided by the portal eminence into two halves, an anterior and a posterior. The anterior, which is deeper, is situated between the depressions of the gall-bladder and the umbilical vein on one side, and the portal eminence and the anterior edge on the other, and has been called from its form the square lobe (Z. quadratus). The posterior is smaller, more elongated, narrower, but more prominent, because situated on a narrower base, is found between the porta, the fissure of the ascending vena-cava, that of the venous canal, and the posterior edge. It is termed the lobe of Spigel ( lobulus Spigelii, s. caudatus). Beside the fissures we have described, we not unfrequently find, particularly in the right lobe, several which vary in size and are not constant •, these are analogous to the division of the liver into many lobes in the mammalia. d. attachments. § 2213. The liver is enveloped by the peritoneum, except the right part of its posterior edge and the portion of its lower face covered by the gall-bladder. This membrane is reflected on it backward by its blunt edge, and forward by the portal eminence or the suspensory ligament. There is no other envelop between it and the tissue of the gland in most of its extent ; we however find an intermediate layer of cellular tissue at the posterior part of the upper face near the edge. E. COLOR, SPECIFIC GRAVITY, AND CONSISTENCE. § 2215. The color of the liver is brownish red in young persons and those in the prime of life. It becomes darkish and blacker in old age. Its specific gravity is about as 15 : 10. Its substance is firm, but brittle. Thus the liver is one of the organs most frequently ruptured, from a mechanical cause acting on the parietes of the abdomen when the external parts are uninjured. F. TEXTURE. § 2216. The parenchyma of the liver is not absolutely homogeneous. In fact we do not find, as in the other glands and the encephalon, the two substances of which it is composed separated from each, so that one is placed internally and the other externally. But whatever point we examine, these two substances, which are every where arranged alternately, are easily distinguished. At first view they seem to form undulated bands about half à line thick ; but when examined more attentively we perceive that the yellow forms a coherent mass in all parts of the gland, that it there produces numerous elevations and depressions, although interrupted in many parts, and consequently represents a very complicated net-work. In the spaces, which are about a line in diameter, and which are polygons, we find a dark substance which does not form a coherent whole like the preceding, and which is softer but less transparent- than it. Ferrein had already well distinguished these two substances. (I) Haller(2) and Gunz(3) also mention its discovery. Autenrieth,(4) Bichat, (5) Cloquet, (6) and Mappes,(7) have also mentioned this structure, which we have always thought was easily seen ; hence we consider as erroneous the opinion(8) that they are arranged arbitrarily. Physiologists, however, differ in regard to their uses. Ferrein terms the deep colored substance the medullary , and the bright colored substance the cortical ; while Autenrieth and Mappes have applied these terms in opposite senses. The views of these last two writers seem to us to be more just than those of the others regarding the difference in the consistence and the transparency of the two substances, in respect to their color, or finally their arrangement in regard to continuity, since in all these respects the bright substance is more similar seems formed of small points or grains. We may term the small masses composed of medullary and of cortical substance the lobules (acini), although they are more blended than in the other glands, and are not separated by spaces filled only with cellular tissue ; so that the structure of the liver is consequently much less lobular than that of the salivary glands. ping when it is cut. § 2217. The liver is formed by the ramifications of the biliary ducts, of the vena-portae, of the hepatic artery and the hepatic veins, and by lymphatic vessels and nerves, united by mucous tissue. It is, however, essentially formed by the biliary vessels and the mucous tissue which surrounds them. § 2218. The vessels of the liver are not all distributed exactly in the same manner. They vary in their connections with each other, and with the substance of the organ. The hepatic artery, the vena-portæ, and the biliary ducts are enveloped in their whole course through the substance of the liver by a common cellular sheath, a prolongation of the capsule of Glisson. Hence they are not in direct contact with the substance of the gland, like the ramifications of the hepatic artery, around which the capsule does not exist, and they are more solid and more resisting than the latter. The hepatic artery seems to be intended for the nourishment principally of the tissue of the liver ; for according to Glisson’s observations/!) which have since been proved correct by Bianchi,(2) Walter,(3) and Mappes,(4) it is distributed on the other vessels, giving rise there to a very complex net-work. The finest ramifications, however, enter the vena-portæ. (5) It terminates in two modes ; several branches, some of which are very large and even a line in diameter, anastomose with the corresponding twigs of the hepatic veins, (2) and hence the facility with which the vena-portæ is injected through these latter, or the hepatic veins through the vena-portæ. (3) Other and more minute branches are more particularly connected with the origins of the biliary ducts ; but their connections are less intimate than those we have mentioned, since by injecting the vena-portæ we can never fill the biliary canals alone, but the injection always passes into the other vessels, particularly into the hepatic veins. (4) Its most minute twigs do not enter into the medullary substance of the liver, but are distributed in the cortical substance, and have no direct or proximate connection with the first.(5) § 2220. The biliary canals differ from the other vessels of the liver, as their twigs are larger. Only the large branches unite in the manner of a disk. The union of the small twigs is less regular, and several proceed from the same point. Their parietes are much firmer than those, of the veins. The muciparous depressions upon their inner face on the outer half of the liver do not exist except in the largest branches, and entirely disappear in the most minute, which are perfectly smooth. When they are injected the injection generally penetrates into no other kind of vessel, or when this happens the lymphatics,(6) and next the branches of the vena-portæ are most perfectly and frequently filled. The roots of the biliary canals seem to arise on the limit between the. medullary and the cortical substance, although they do not distinctly pass through the former.(7) They never terminate on the surface of the liver, and even when they are superficial, they penetrate within the gland. 2221. The twigs of the hepatic vein are also fewer and larger than those of the vena-portæ and the hepatic artery. They do not contribute as much as the vena-portæ, to form the substance of the liver, (8) although their less degree of development is only apparent, since their twigs are so small, that they are more easily destroyed than the other hepatic vessels. When injected, the fluid scarcely passes, excepting into the vena-portæ. (9) Their direction is generally transverse, while that of the other hepatic vessels is oblique from below upward, and almost perpendicular, so that they cross these latter. Their final twigs are more intimately connected with then: medullary substance than those of the other hepatic vessels, and it is more or less easy to trace them into this substance, which depends partly on their not being surrounded like these latter by the cellular capsule. § 2222. The lymphatics of the liver are intimately connected with the biliary ducts, and then cavity directly communicates with them, or at least the substance between them is extremely thin, soft, and easily destroyed. Those of the different regions of the liver do not anastomose together, for the injection of one branch fills only the portion of the organ to which this branch is distributed. B. EXCRETORY PORTION OF THE BILIARY SYSTEM. § 2223. The excretory portion of the biliary system includes the proper excretory duct of the liver, and a cul-de-sac of this canal termed the gall-bladder ( cystis , s. vesicula fellea, cholecystis) . A. EXCRETORY DUCT. § 2224. The excretory duct, of which we have already described the portion within the liver, is formed by two membranes, one external, solid, and cellular, the other internal, thicker, and smooth presenting numerous and very compact depressions. We distinguish in it three portions, the hepatic canal, the cystic canal, and the ductus choledochus. The hepatic canal ( d . hepaticus ), or the first portion of the excretory duct, arises in the fissure of the vena-portæ generally by two branches, one on the right, which is smaller, and comes from the anterior part of the great lobe of the liver, the other on the left, which is larger, and arises from the posterior part of this lobe, and from the left lobe. These two branches anastomose at an acute angle before leaving the fissure of the vena-portæ. The canal formed by their union is from one and a half to two inches long, and nearly two lines broad in the normal state ; it is directed from above downward, and from right to left, and divides to give rise to the cystic canal and the ductus choledochus, which make a part of it. The cystic canal ( cl . cysticus ) is directed at an acute angle forward, downward, and to the right. It is narrower, and usually a little longer than the hepatic, and enlarges to form the gall-bladder. § 2225. The gall-bladder is situated in a special depression of the lower face of the liver. It is usually pear-shaped. The extremity, near its orifice, termed the neck (cervix), is the narrowest part ; it is broadest in its centre. Its anterior extremity terminates in a cul-de-sac, and is called the base ( fundus ) ; it commonly extends a little beyond the anterior edge of the liver. •The gall-bladder generally adheres in- timately by its upper part, to the lower face of the liver, but sometimes also it is loosely united with it by a fold of the peritoneum. The peritoneum covers it more or less perfectly, according as it presents one or the other of these two arrangements. We find below the peritoneum a dense cellular tissue, in which proceed the large vascular trunks, and which is called the vascular or nervous tunic. The external face of the second tunic presents some fibres which are generally whitish, proceed in different directions, sometimes very analogous to those of the muscular coat of the intestinal canal, and which cannot be considered as forming a distinct layer. The cellular tunic covers the internal or mucous membrane, the inner face of which presents folds which represent a reticular tissue, formed of irregular pentagons, which do not disappear even when the gall bladder is in its greatest possible state of distension. Some very small openings, which are observed on this face, lead to simple glands which are commonly invisible. Only ramifications of veins are distributed on the surface of the folds. The cystic canal and the neck of the gall-bladder are contracted by about a dozen transverse folds, which are real valves, and arise from the internal and cellular tunics. Most of these folds have their loose edge turned toward the cavity of the gall-bladder, so as to form between them and the wall of the canal, a depression which has the same direction. These folds gradually enlarge from the hepatic canal toward the neck of the gall-bladder. They are attached to each other, especially the largest, by intermediate, longitudinal, oblique, elevations which are less prominent. § 2226. The ductus choledoclms , or the lower portion of the excretory canal of the liver, is the continuation of the hepatic and the cystic ducts. It is a little broader than these two canals, but it is more similar to the hepatic in structure and diameter, and may be considered the direct continuation of it, for it has the same direction, and there exists, at least very frequently, along the opening of the cystic canal, a small elevation between it and these two passages. This canal is generally about four inches long ; its lower extremity goes to the posterior wall of the duodenum, and opens at its central portion. Its diameter is generally the same until it opens into the intestine, but it contracts much in gliding between the muscular and cellular tunics of the latter, and finally terminates in an orifice which is narrower than the rest of its course. § 2227. When we cut the duodenum, we observe in the posterior wall, the opening of the ductus choledochus, in the form of an oblong tubercle, about four lines in length, and presenting at its lower extremity an opening directed obliquely from above downward ; this opening is generally situated three inches below the commencement of the intestine, and is formed by the mucous and cellular membranes of the latter and the ductus choledochus, which are uninterruptedly continuous with each other. dochus alone, but it is common to the pancreatic canal. § 2228. The most evident function of the liver, is the very important one to secrete bile, a green, very bitter alkaline liquid, which is indispensibly necessary to digestion ; its physical qualities vary much in more than one respect. The bile is generally distinguished into cystic and hepatic ; the first is thicker, darker, more bitter, and consequently more concentrated than the second ; which differences depend on the gall-bladder, and not on the different origin of these two fluids, although Malpighi(l) and Galeati(2) have adopted this last opinion, or at least in part. centration, the bile has not always the same chemical composition. It always contains a considerable quantity, and generally about eleven-twelfths of water. The rest is composed, according to Thenard, of albumen and of resin, of each about an equal quantity, which form almost the whole of it ; a small quantity of insoluble yellow substance, of a still smaller quantity of soluble substance, finally, some traces of soda, of the phosphate, the sulphate, and the hydrochlorate of soda ; of the phosphate of lime, and of the oxide of iron, all of which are dissolved in the water except the yellow substance, which is insoluble. (3) The resin admitted by Thenard and his successors, is produced, according to Berzelius, (4) by the action of acids on a peculiar substance, similar to albumen. This chemist considers bile composed in 1000 parts : of water 907.4 ; of a peculiar substance 80.0 ; of mucus 3.00 ; of soda and common salts 9.6. None of these constituent parts contain azote ; this is curious, on account of the frequent change of bile into a fatty body, and on account of the analogy of the meconium with vegetable substances. Thenard asserts that picromel, a peculiar substance of a sweet and bitter taste, which commonly occurs in the bile of most mammalia, does not exist in that of man, but it has been found there by Chevalier.^) 4th. The relation between the caliber of the hepatic vein and the size of the liver, without regard to the abundance of the biliary secretion, while this latter circumstance is always attended with a greater development of the vena-portæ. the hepatic artery is unusually large. 3d. The correspondence between the caliber of the excretory duct of the liver and that of the hepatic artery, and the disproportion between that of the hepatic canal and that of the vena-portæ. These arguments do not refute those on the other side. We have reasons for thinking that the arterial blood of the invertebral animals is perhaps more proper for the secretion of bile than that of the verte brated animals. Possibly, also, the arterial blood of the latter was more appropriate for this use in the anomaly on which the second argument rests, than generally, because the biliary secretion then did not contribute to render the blood of the vena-portæ more analogous to that which circulates in the arteries. Farther, all the known cases of this anomaly have been observed in children, the bile being less bitter and less in quantity than usual. As to the third objection, the hepatic artery compared with the arteries of the other secretory organs, seems too small to admit that it serves for secretion and nutrition. Some physiologists, regarding the size of the liver, its constant existence, and the frequency of its diseases, have been led to believe that it fulfills in the economy another function from that of secreting bile ; but this other function is not proved. Theuses of the bile .are not confined to digestion, but it is connected with the whole vital action ; in this respect, the secretion which forms it, prevents an excess of hydrogen and carbon in the body, as is indicated by its increase when the respiratory function diminishes in the animal series, when it does not exist as in the fetus, or when it is deranged as in certain diseases. (1) The purpose of the circulation of the vena-portæ, however, may also be to attenuate, to assimilate foreign substances brought by the venous system into the intestinal canal, and thus diminish the injurious influence they might exercise on the body. tionally much larger the younger the fetus is. Thus, in the fetus of three weeks, its weight is one half that of the rest of the body,(l) and even in the full grown fetus it is to the latter as 1 : 18, or as 1 : 20, while the relation is as 1 : 35-36 in the adult. But the great proportional size of the liver diminishes at the end of the first half of gestation, because, after this period, the gland increases more slowly. It, however, continues to grow till birth ; but afterward the absolute weight and size diminish until the end of the first year, for we have found in five new born children, that the liver was one quarter heavier than in five other children from eight to ten months old. 2d. The liver at first occupies a much greater space the younger the fetus is ; even at the third or fourth month of gestation, it nearly fills the cavity of the abdomen, descends to the crest of the ileum, and covers the other viscera. This difference, however, partly depends upon its being situated more perpendicularly at first, so that then, that face which is afterwards superior, looks forward, and that which is to be inferior, backward. 3d. Its formation is at first as much more symmetrical as is its situation, and it's left lobe differs less in size from the right lobe, and the limit between these two parts corresponds more to the median line. The absolute diminution mentioned above, takes place almost entirely at the expense of the left lobe, for while during this period, the right lobe preserves the size it had at birth, and often even increases a little; the left diminishes in every direction, so that in a child of a year old, it is hardly half as large as in a new born child ■ the lobe of Spigel, on the contrary, is more developed. The liver is at first more rounded, and its lower face is more convex than it is afterwards. 4th. Its tissue is softer, more homogeneous, more brittle, and more vascular in the earlier periods of life than subsequently, where the vessels diminish in size, and many of them disappear. We, however, very readily distinguish the two substances in the full grown fetus. 5th. Its coloris at first a bright grayish brown ; it does not become a deep red until after the first half of gestation ; its tint brightens shortly after birth, and its tissue then changes also a little in appearance. § 2230. The gall-bladder isatfirst entirely concealed in the substance of the liver, is proportionally very long, narrow, filiform, a little enlarged at its lower extremity, and empty. Its cavity cannot be seen except by the aid of the microscope. Its inner membrane is smooth until the sixth month of gestation ; broad, irregular elevations are then developed in it, between which are narrow depressions, similar to superficial grooves. These grooves gradually become deeper, and also more numerous, and many fissures are developed on the surface avance; in the Mémoires de Paris, 1771. — Id., Observations sur la situation du foie dans l’etat naturel, arec des remarques sur la manière de connaitre, par le tact , plusieurs de ses maladies ; in the Mém. de Paris, 1773. — J. S. Schumann, Dehepatis inembryone magnitudinis causis ejusdcmquefundionc cum infœlutum inhomine nato, Breslau, 1817. are separated by .thin intermediate septa. Notwithstanding its primitive narrowness, the gall-bladder is never deficient at any period, according to our observations, as one would be led to believe from some cases where its total absence has been asserted. Its situation also in regard to the other biliary organs, is always the same- ~ consequently it never arises by a kind of granulation, developed from the extremity of the biliary passage, but it arises in the groove at the lower part of the liver, which is destined particularly for it, and which is at first proportionally much deeper than in the adult. We have never known it to communicate with the liver at first by one or more 6peciul canals, while we have seen it manifestly terminate in a cul-de-sac. § 2231. The liver is one of the organs most(l) frequently abnormal in more than one respect, but principally in its texture, which undoubtedly depends on the numerous organic elements which compose it § 2232. The deficiency of the liver has hitherto been observed onlyin some acephalous monsters ; in these it is the rule, which has but few exceptions, that the liver is always very small. This organ sometimes preserves the same situation as in the fetus, which depends on the imperfect development of the anterior face of the abdomen. In this case it is sometimes situated externally, forming either alone or with the other viscera, an umbilical hernia, in which it is wholly or but partially contained. It exists more rarely in the cavity of the thorax, on account of the imperfect development of the diaphragm. Sometimes, in these two cases, especially the first, the herniary part, forms a prolongation, which is attached to the peduncle , this may give rise to the opinion that two livers exist. Sometimes, also, when no similar mechanical cause exists, the liver is divided by more or less deep grooves, into a greater or less number of distinct lobes. Sometimes an anomaly of the liver exists, similar to the latter in external appearance, but differing much from it in form and origin. It consists in fractures of this organ, which are frequent on account of its fragility, even when the external parts are uninjured from externa! (1) Portal, Observations sur la nature et le traitement des maladies de Joie, Paris, 181 3. — Farre, The morbid anatomy of the liver , London, 18121815. — J. Thomas, A treatise on the diseases oj the liver and digestive organs , London, 1820.— J. Johnston, A treatise on derangement of the liver, London, 1820. — J. Faithorn, Facts and, observations on liver complaints and bilious disorders in general, Philadelphia, 1820. ted, but also upon remote parts. It is rare that the liver is abnormally small from a primitive deviation of formation, but it often diminishes in the course of time, particularly in advanced life, and finally becomes unusually hard and firm ; this state is termed scirrhus , although this term is not perfectly convenient.- Hypertrophy (1) of the liver is one of its most common affections ; it supervenes at all periods of life, but most frequently in advanced age : it is generally attended with a greater or less alteration of texture, and particularly with induration , even when it does not depend solely on new formations within the gland. Induration of the liver, however, is not always attended by its hypertrophy, although the contrary is generally admitted, since the latter is sometimes attended with softening. Hypertrophy of the liver frequently attends chronic general diseases, especially rachitis, scrofula, and dropsy. In this case the gland is usually harder than in health : but in scrofula, on the contrary, where we find hypertrophy at least as frequently, its tissue is softer than in the normal state. The enlargement,of the liver, which usually attends pulmonary affections, is evidently, at least in most cases, an effort of nature to restore health. Induration of the liver is the most frequent alteration of texture, and it often exists with or without enlargement. Softening of the liver is much more rare, and exists sometimes with, and sometimes without atrophy of the gland. (2) The new formations in the liver are rarely repetitions of the normal tissues : the most common anomaly is the change into fat, which exists in several different degrees, usually affects the whole organ, and is observed in the idle and luxurious. Accidental ossification is generally developed on the edge of the liver, below the peritoneal coat. Probably it is only a change of another accidental formation, for instance, of one of those serous or fibroserous cysts, often developed in the liver, where they form hydatids. The liver is not unfrequently the seat of entirely new formations, generally termed tubercles (tuber a) .(3) These tumors are rarely inclosed in a cyst, and are rounded. They are generally whitish, seldom red or brown. They vary in size from three to four inches. They are frequently very numerous, being developed in the centre of the liver, which is otherwise healthy. Like most new formations, they are (3) V. Murad Des moyens de distinguer entre elles les diverses affections du foie, désignées sous les noms de tubercules scrofuleux, d'hydatides, de squirrhe, d'hydropisie enkystée, généralement confondues sous le nom d' obstructions ; in the Bull, de la soc, méd. d' émut-, September, 1821. generally albuminous.(l) Those, however, which have a brownish tint, appear from some recent experiments, to be more analogous with gelatine. (2) The diseases they resemble are principally scrofula or fungous hæmatodes. AH the anomalies in the mass, size, and consistence of the liver hitherto mentioned, all the accidental formations mentioned in this gland, supervene principally after the immoderate use of arderlt spirits. As they render the liver unfit for the secretion of bile, or prevent the excretion of that which it forms, they frequently occasion jaundice. This affection depends on a deposition of bile in a greater or less number of organs and fluids, particularly in the skin. It may also be determined by the adjacent organs, and sometimes we discover no alteration to which it can be attributed. From the important functions of the liver, and also the intimate connection between it and the mind, this organ varies more or less in all general chronic and in all mental affections. Entozoaries are developed in this gland more rarely. ' The animals most commonly found there are hydatids, which occur in the liver more frequently than in any other organ ; they are extraordinarily large and numerous, and form very rapidly ; they are generally developed in one point, rarely in several, and most commonly in the right lobe. They are commonly separated from the healthy substance of the organ by cysts, usually formed by several layers. They not unfrequently destroy the liver to a great extent, and quitting the place where they are formed, generally proceed outward, most commonly by entering into the intestinal canal, more rarely into the chest and lungs, sometimes even directly through an opening in the common integuments. § 2233. Sometimes, but rarely, a part of the biliary passages, particularly the gall-bladder, is deficient(3) from a primitive deviation of formation, although this anomaly does not necessarily exercise an injurious influence on the health, which is less astonishing, since, accor ding to the experiments of Herlin, the gall-bladder may be extirpated in cats without inconvenience, and it is normally absent in many animals. On the contrary, the entire absence of the biliary passages(4) is always attended with the most fatal results. We rarely also meet in the biliary passages deviations of formation in regard to the quality, such as the existence of hepato cystic ducts (d. hepato-cystici ), going directly from the lower face of the liver into the gall-bladder, the slow union of the two roots of the hepatic canal, the opening of one or more branches into the cystic canal, or even into the gall-bladder, the insertion of the ductus choledochus in a point different from the intestinal canal, or even in the stomach. Of all the biliary passages, the gall-bladder most frequently presents anomalies of this kind, since when it is divided by a contraction into two cavities, placed successively in a longitudinal direction, or, as is more rare, when a longitudinal septum divides it into two parts adapted one to the other. The enlargement and the contraction of the biliary passages generally depends on mechanical causes, among which we must place first the biliary calculi contained within them, next, as is more rare, the engorgement of the lymphatic glands, which compress it from without inward.(l) The gall-bladder may be contracted or dilated by the calculi within it. The contraction and the total obliteration of its cavity occur when a few or small calculi prevent by their situation the bile from entering it. On the contrary, numerous or large calculi, either alone or together with the bile, often dilate the gallbladder considerably when they are so situated as not to prevent entirely the entrance or departure of the bile, or when they exist in the ductus choledochus. Sometimes the gall-bladder is enormously distended, simply by an increased secretion of bile, without any mechanical obstruction ; the membranes of this latter are then generally thin, while in the opposite state they are very thick. Sometimes the calculi are separated by perfect septa. New formations rarely occur in the gall-bladder ; we must mention as such, however, the osseous plates sometimes developed on the outer face of the mucous membrane, and the hairs inserted on its inner face. (1) Andral ( Observations sur l’oblitération des canaux biliaires; in the Archiv, gen. de méd., vol. vi., p. 16) admits four principal causes of perfect or imperfect, transient or permanent obliteration of the biliary passages ; these are the obstruction of their cavity by a foreign body, a compression upon their parietes by membranous folds and by tumors of different kinds, a spasmodic contraction independent of all inflammation, and an inflammation followed by the engorgement of the mucous membrane and its thickening. He remarks that the first two causes are frequent, that in most cases the third has rather been supposed than demonstrated, and that physicians have not yet attended to the fourth. The latter, however, seems to be, if not always, at least very frequently, a consequent of a gastro-intestinal inflammation; it is not unusual, and we have every reason to think that it always exists in thé cases where the nervous pathology led one to suppose the third. Like all inflammations, that of the biliary passages, whether acute or chronic, is attended with the thickening of the parietes of the canal, which is finally changed into a ligamentous cord. F. x. C, BILE. § 2234. The bile is often abnormal in its physical and chemical qualities, although we cannot always discover a certain connection between its anomalies and the state of the liver. It however seems less bitter when this organ is changed into fat. These concretions, which are found in aged persons, or in those who lead a sedentary life, differ from each other in situation, composition, •color, number, size, texture, form, and consistence. 1st. Situation. The biliary calculi generally occur in the gall-bladder, so that they seem to be developed in this organ. They have been found also in the biliary passages, in the substance of the liver, although proportionally very rarely. Sometimes also they are situated in the hepatic or cystic canal, or in the ductus choledoch us, but they finally fall into the gall-bladder. Not unfrequently they leave the ductus choledochus and pass into the intestinal canal. The rarest case is where they occur out of the cavity of the biliary passages in the substance of the liver, or in the membranes of the gall-bladder. The former may be formed in the place where they occur ; but the second are doubtless primitively developed in the cavity of the gall-bladder, and afterwards glide between its membranes, and are then inclosed by the closing of the opening which at first existed, although it is admitted they are formed in the place even where they are observed ; and this fact has even been cited to prove that the bile is partially secreted by the glands of the gall-bladder. (2) The justice of our etiology is demonstrated by the fact, that calculi are sometimes found in the depressions of the gall-bladder, which case is evidently intermediate between that where they are entirely loose in the cavity, and where they are situated on the outside of it and encircled in the membranes. 2d. Chemical composition. The chemicafcomposition of the biliary calculi generally causes all those properties of which we have yet to speak. They are composed principally of two different substances ; one more or less dark in color and brownish, and the other white ; the latter is termed cholesterine. The bile contains none of it in the normal state. (3) The other is the yellow coloring substance of this (1) Vicq-d’Azyr, in the Mém. de la soc. de mid., 1779.- — Fourcroy, Sur les calculs des animaux ; in t lie Annales du Muséum, vol. i. — S. T. Sœmmerring-, De concrementis biliariis, Frankfort, 1793.— Mosovius, Diss. de calculorum animalium origine et naturâ, Berlin, 1812. 3d. Color. These concretions are more or less colored from the brighest yellow to the deepest dark brown, because they generally contain the substances mentioned above. Those only which are formed of cholesterine are entirely white, and they are very uncommon. Farther, the tint varies in the different parts of a biliary calculus. formed of pure cholesterine are usually single, or at least very few. 5th. Volume. It varies no less than the number, and usually hi an inverse ratio. The calculi of pure cholesterine are generally larger than the compound concretions. Not unfrequently one of them fills the gall-bladder, and even distends it. 6th. Form. The biliary calculi are generally more or less round ; those of pure cholesterine are more oblong. Their form is modified also by their number, since the friction between them renders their surface smooth. Hence why those of cholesterine are generally more corrugated than the others ; but these concretions rarely present sharp points. lored layers. c. These layers are sometimes, though rarely, composed of one of the two substances mentioned above. In the contrary case they are all colored, and differ only in their shade of color. We not unfrequently find externally an entirely white layer. d. The fight colored layers have generally more oi less evidently a radiated and fibrous texture. It is often easy to see that they are formed of very oblong pyramids slightly connected with each other, the summits of which converge towards the centre. This form seems to depend on the cholesterine, for it is never more apparent than in the calculi formed by this fatty body, and it decreases inversely with the color. e. Consistence. Biliary calculi generally are neither very hard nor solid. They are much softer and more brittle than the urinary concretions. Sometimes, however, they are considerably hard. Those of pure cholesterine are generally harder than the others, being even very firm and solid ; but they are frequently also very soft, while others which are more deeply colored are considerably hard. II. PANCREAS. § 2235. The pancreas( 1 ) is the largest of the salivary glands. Its weight and size are three or four times those of the parotid gland, as it is six inches long and one thick, and weighs from four to six ounces. It is oblong, and is situated transversely at the upper part of the abdominal cavity, before its posterior wall, in front of the first and second dorsal vertebra, behind the stomach. Its left extremity generally touches the spleen and the left kidney. It passes before the aorta, and its right extremity is situated between the upper and lower folds of the duodenum. riorly: Its figure is that of a hammer, since it enlarges at its right extremity, from whence proceeds an inferior prolongation, which embraces the duodenum posteriorly, and on the left, and even a little forward. The lower prolongation is called the /read, and the transverse larger portion the tail. § 2236. The pancreas is attached to the adjacent parts by a very loose cellular tissue, and enveloped by a thick layer of the same ; it has no special capsule. We also distinguish through the cellular envelop, the lobes which unite to form it. The pancreas is yellowish brown, and rather firm in its texture. § 2237. A considerable excretory duct passes entirely through this organ ; it is white and solid, and is called the pancreatic canal (ductus pancreaticus) ,(l ) or the canal of Wirsung (ductus TVirsungianus). This canal arises at its posterior extremity by the union of several branches, which anastomose at an acute angle. In its course it receives at a right angle, both above and below, a considerable number of other branches, which may be easily followed by smaller granulations, so that it gradually increases in volume, and finally becomes a line and a half in diameter. Just before quitting the gland, it also receives one or more very large twigs, which arise from the head, and which also open separately into the duodenum. cut across in order to see it. (1) Brunner, Exp. nova circa pancreas , Amsterdam, 1638. — Graaf, Dc succo pancreaiico, Leyden, 1664. — Johrenius, Dc affect, hypoehondriacis , Rinteln, 1678.—.). M. Hoffmann, Dc panercale, Altdorf, 1706.— J. D. Santorini, Tabula: scptcmdccim, tab. xiii. In the place where it communicates with the duodenum, it unites externally with the ductus choledochus, but the two cavities remain perfectly distinct, even when proceeding side by side through the membranes of the intestine. They open side by side near the pancreatic duct, a little to the left of the choledochus, at the base of a small cavity about two lines long, the membrane of which has all the characters of the inner tunic of the duodenum, so that we cannot properly consider them as having a common orifice. Near its orifice the excretory duct of the pancreas enlarges more or less, but contracts at its opening, although there is no fold similar to a valve in this or in any other part. The appearance of a valve at its opening depends only on the septum between it and that of the ductus choledochus. subsequently. We have observed that its excretory duct very constantly presents a remarkable difference, as it is at first double, that is, beside the permanent valve, there is then a second, which opens separately into the duodenum.(l) § 2239. The congenital anomalies of this gland extend principally to the arrangement of its excretory duct, which sometimes seems double ; this state must be considered as a permanence of that in the fetus. (2) The most remarkable consecutive anomalies are induration and hypertrophy. We more rarely find in its excretory duct, calculi, (3) composed of phosphate of lime and of an animal substance. (4) F. Schuyl, Dénatura etusulienis, Leyden, 1664. — Malpighi, I)e liene ; in De structura viscerum. — C. Drelincourt, Dc licnosis, Leyden, 1693. — G. Stukcley, The spleen , its description , uses , and diseases, London, 1723. — J. G. Duvernoi, De liene ; in the Comm. Petrop., vol. vi. p. 156. — S. T. Quellmalz, De liene, Leipsic, 1748. — C. L. Rolof , De fabrica et functions lienis, Frankfort, 1750. — Lasson e, Histoire anatir mique de la rale ; in the Mém. de Paris, 1754. — Werlhof, De splenis usu, Wolfenbuttel, 1761. — J. F. Lobstein, De liene , Strasburg, 1774. — J, P, P. Assolant, Recherches sur of the diaphragm, the commencement of the descending colon, and the left renal capsule, which it covers anteriorly. Its form is elliptical ; its posterior or external face is convex ; the anterior or internal is concave, and divided by a longitudinal groove called the fissure of the spleen ( hylus lienalis), into two halves, an anterior, which is the larger, and a posterior. Its upper extremity is a little thicker than the lower ; a fold of the peritoneum unites it to the diaphragm, the stomach, and the descending colon. It varies much in size, not only in different individuals, but also in the same individual at different periods, and inconstantly. In general we may say, that in the adult it is about four inches long, three broad, and a little less than one thick. Its weight varies as much as its size. Its mean weight is eight ounces, so that in the adult it is to that of the whole body as I : 210. But the volume and the weight of this organ are not necessarily in an inverse ratio with the distension of the stomach, as has been asserted. (1) Its specific gravity, compared with that of distilled water, is as 1.200 : 1000. § 2241. At first view the spleen seems formed entirely of blood-vessels, of which the arteries come from the cœliac trunk and the veins rest directly on the surface of the artery, and are proportionally larger than in any other part of the body ; they empty into the vena-portae, and carry there a very dark blood. The substance of the organ is surrounded by a very firm sero-fibrous membrane. The external layer is serous and comes from the peritoneum, with which it is continuous by two prolongations mentioned above. Numerous layers and very minute solid fibres proceed from it, which interlace in many different ways, and enter the space circumscribed by the capsule, leaving between them irregular spaces, in which the splenic vessels are distributed. the spleen. Beside these fibres, other hollow canals proceed from the inner membrane of the spleen to its fissure ; these closely envelop the vessels, and unite with them. The first filaments are attached to the outer la rate, Paris, 1801.— A. Morcschi,->SW vero eprimario usu della milza, Milan, 1803. — E. Home, On the structure and use of the spleen ; in the Phil, trans., 1808. — C. F. Heusinger, Ueberd.cn Bäu und Verrichtung der Milz , Thionvillc, 1817.— F. Gellhaus, Inaugural Abhandlung über den Nutzent der Milz, 'Wurzburg, 1817.— G. M. Felici, Osservazioni fisiologiche sopra lefunzioni della milza, Milan, 1818. — I. Deellinger, Betrachtungen über die Milz ; in the Deutsches Archiv für d.ie Physiologie, vol. vi. p. 155.— Jæckel, Etwas über die Verrichtung der Milz ; same journal, vol. vi. pi. 581.— Hodgkin, Sur les fonctions de la rate; in the Journ. com.pl. des sc. méd., vol. xiv. p. 89. — Home, in the Phil. Irans., 1821, p. 25. fibrous capsule. The splenic arteries give off in their course numerous branches, which divide into very minute ramuscules, arranged like the bristles of a brush, but they do not anastomose together. On the contrary, the veins which surround these arterial fasciculi, frequently anastomose with each other, and with the adjacent veins. There are, however, no great communications between the arteries or the veins of the different regions of the spleen. Those between the veins and arteries are very large, as may easily be seen by the aid of a microscope, or by the facility with which injections pass from the arteries into the veins. Besides the blood-vessels, the spleen also possesses numerous lymphatics. Its nerves come from the splenic plexus, and are very small. They are scarcely one twelfth as large as the arteries they surround, and we cannot trace them far within the organ. Beside these constituent parts, which several anatomists assert are the only ones, the spleen also contains, according to the more correct observations of others, particularly Malpighi, Hewson, Dupuytren, Home, Heusinger, and Meckel, very many rounded, whitish, and very probably hollow, or at least veiy soft corpuscles, which differ much in respect to size and situation ; their size varies from one sixth of a line to one line, and they are sometimes near, and sometimes rather distant apart. « These corpuseles are very intimately connected wtth the rest of the tissue of the spleen, and receive many blood-vessels; according to Home’s observations, confirmed by those of Heusinger and our own, they swell much in animals when they drink. Malpighi considers them as glands. Ruysch and several other anatomists have denied their existence, and have asserted, but wrongly, that they are only simple fasciculi of vessels. Although neither these corpuscles, nor the spleen, have excretory ducts, they very probably contribute much to the changes of the blood in passing through this organ, and assist in forming the gastric juice, but particularly the bile. The substance of a reddish brown, easily separated by washing and pressure, should be regarded not as a constituent part of the spleen, but as the blood changed by this organ. The cellules heretofore admitted in the spleen, were very probably produced by the destruction of a part of the vessels, and of the internal fibrous tissue, by injections made with too much force, whence were formed spaces which are afterwards distended by inflation. § 2242. As the spleen has no excretory duct, its functions are very obscure, and the more so, as it has frequently been extirpated without producing any constant or very great derangement in any function. Even at present, after so many experiments infinitely varied, after so many observations and reflections, we can only hazard conjectures on this subject. We may, however, conclude from facts hitherto known, and stomach, and acts in concert with these two organs. That it assists in the functions of the liver, is proved by the fact, that all the blood which passes through its tissue, is carried to this organ by the trunk of the vena -portée. Hence, we may conjecture, and very probably, that the blood is changed within it, and rendered more proper for the secretion of bile, which conjecture is not contradicted by chemical experiments, from whence it has been concluded, that the blood of the splenic veins does not differ from that in the other veins. Possibly, also, the spleen contributes mechanically to increase the secretion of bile, since, during abstinence, a greater or less quantity of blood collects there, which is afterwards expelled by the pressure of the stomach when filled with food, and then goes toward the liver. But as the blood is not merely circulated in the spleen, but there undergoes some change, it follows, that the relation is not mechanical only, but also chemical. The spleen receives less blood at the commencement of digestion, because the stomach, which is then full, prevents the blood from flowing freely into it ; but in proportion as the contents of the stomach pass out from it, the blood flows more easily to the spleen, and the function of this latter, in regard to the . liver, becomes more active. Probably also the spleen concurs in the accessory function attributed above to the liver, that of neutralizing and assimilating foreign substances introduced into the body. Hence we must consider it as a viscus which performs, in regard to the vascular s3rstem, particularly to the liver, the same part as the conglobate glands towards the lymphatic system. It is more analogous to these glands than to the liver, as it has no excretory duct. The liver then appears as an organ composed of a conglomerate and a conglobate gland in the vascular system. several different respects : 1st. In a dynamical respect, since the two organs seem to be opposed to each other, and the soft and blackish spleen may be considered, from its substance and the change of the blood which passes through it, as contributing particularly to produce hydrogen, while the stomach is an organ which, from the nature of its secreted fluid, tends particularly to produce oxygen. 2d. In a mechanical respect, as the spleen attracts the blood to it when digestion is not guing on, while it receives less when this viscus is full, so that the blood flows in greater quantity toward the latter, that is, precisely at the period when most necessary to the secretion of the gastric juice. The function of the spleen seems also to be to receive promptly at least a part of the liquids introduced into the stomach, although this function does not belong exclusively to it, since after it has been extirpated the liquids disappear as quickly as before, and the substances contained in this viscus reappear in certain fluids. the successive periods. All these peculiarities are very important, as they support the eighth law established in our introduction. In fact the spleen does not exist in the mollusca which have a liver ; it becomes proportionally smaller and smaller as we descend from the mammalia toward the lower classes of the animal kingdom ; and in most mammalia, as also in several other animals, the corpuscles are regularly larger in proportion than in man. ticed. This organ is very rarely deficient from a primitive deviation of formation in a subject where the formation is otherwise normal, while it is generally absent in cases of acephalia vera. A deviation of formation almost peculiar to the spleen, or at least observed in it more frequently than in any other organ, is its division into several spleens termed accessory ( licnculi , s. lienes accessorii). These accessory bodies are always situated on the inner face, and generally toward the lower extremity of the spleen. They are usually, but not always, rounded, and vary in number from one to twenty-three. The latter number, however, has been observed only once, and we rarely find more than one supernumerary spleen. The great number of these accessory spleens is usually attended with other deviations of formation. This occurred in a subject who had twenty-three. (2) In another case, where there were seven, all the organs of vegetative life were at the same time inverted. (3) In a The accessory spleens vary much in size. The existence of a great number of fissures which are frequently very deep on the anterior edge of the spleen, particularly toward its lower extremity, or of a more or less distinct transverse fissure, which passes over its whole external face, form a remarkable intermediate degree between this anomaly and the normal state. Among the accidental deviations of formation, one consists in an enlargement of the spleen, usually attended with induration, which commonly arises from the metastasis of a general disease. (2) attended with great debility. New formations are rarely developed in the spleen. The tubercles sometimes seen in it are probably white corpuscles somewhat enlarged. Perhaps we should consider a special formation a solid uneven yellowish white mass which is frequently developed in the spleen. It, however, seems to be very similar to fungus liæmatodes. The capsule of the spleen frequently ossifies, particularly in advanced age, to such an extent even that when the osseous substance has acquired a certain thickness in proportion to which the organ always wastes, we are led to think that the spleen itself is changed into bone. DIGESTIVE ORGANS. § 2245. The vessels of the most important and the largest part of the digestive organs mostly arise from three trunks, the cceliac, and the superior and inferior mesenteric arteries, which come directly from the abdominal aorta, and anastomose very frequently together. The lower extremity of the rectum also receives some branches from the hypogastric artery. The veins, if we except those of the lower part of the rectum which empty into the iliac veins, unite and form the vena-portae, so that all the blood that returns from these organs passes through the liver before going to the heart, and from thence into the lungs. (2) C. F. Heusinger, Ueber dir, Entzündung und Vergrosscrung der Milz, Eisenach, 1820. — S. Grotlanelli, Ad acuta: et ceronica: splenüidis h.istoriam animadversioncs, Florence, 1821. — C. 11. Schmid, Cummcnlatiu de palhulogiû lienis, Gottingen, 1816. OF THE ORGANS OF VOICE. The nerves come principally from the great sympathetic nerve. Those of the stomach, however, arise chiefly from the pne.umo-gastric nerve, and those of the rectum from the sacral pairs. ORGANS OF VOICE AND RESPIRATION. § 2246. In the preceding chapter on the systems we described the digestive organs which belong to vegetative life ; these appear earliest in animals, or in the fetuses of animals, perform at first the functions of all the rest, and are the type on which these latter are formed, which are, however, less perfect and much less complex. We now proceed to describe the respiratory organs, in which the nutritious fluid formed in the first is in general perfected. The vocal apparatus is so connected with the organs of respiration that it occupies the summit of the canal by which these latter communicate with the air by the cavities of the nose and mouth, and it is in fact only a development of the upper extremity of this canal. It is then most convenient to begin with it. § 2247. The organs of voice(l) are composed principally of the larynx, in which the voice is formed, although it is modified in different modes when passing through the cavities of the nose and mouth, which are situated before it. several cartilages, of ligaments which unite them, of muscles which (1) Galen, Vocalium instrumentorum disscctio: in the Opp. omn. — Fabricius of Aquapendente, De visione, voce, etauditu: Id., De laryngé vocis instrumenta: in the Opp. omn.^—3. Casserio, De vocis auditusqvc organis , Ferrare, 1600. — D. Santorini, De laryngé : in the Obs. anat., c. vi. — A. F. Walther, De laryngé et voce , Leipsic, 1740.— R. A. Vogel, De laryngé humano et rocis formatione, Erfurt, 1747.— J. G. Runge, De voce ejusque organis, Leyden, 1753. — Hérissant, Recherches sur les organes de la voix des quadrupèdes et de celle des oiseaux : in the Mêvti. de Daris , 1753.— J. M. Busch, De mec/ianismo organi vocis hujusque functione, Groningen, 1 770. — Vicq-d’Azyr, De la structure des organes qui servent à la formation de la voix, considérée dans l'homme et dans les différentes classes d’animaux : in the Mém. de Paris, 1779, p. 178-206.— J, WolfT, Diss. de organo vocis mammalium, Berlin, 1812. move them, and of a mucous membrane which covers them in every part, after which it is continuous upward with the buccal membrane, below with that of the trachea. This cavity gradually contracts a little from above downward. It is situated at the upper and anterior part of the neck, below and behind the lower jaw, between the trachea and the cavities of the nose and mouth, of which it is the direct continuation. § 2249. There are nine cartilages which form the base of the larynx, three of which are unmated and six exist in pairs. The pairs are situated on the sides ; the unmated are divided by the median line into two equal halves, a right and a left. The unmated cartilages are the largest, and principally form the whole larynx. They are the thyroid and cricoid cartilages, and the epiglottis. The pairs are the arytenoid , the rounded , or the tubercles of Santorini , and the cuneiform cartilages. I. THYROID CARTILAGE. § 2250. The thyroid cartilage (C. thyroidca ), the largest of the cartilages of the larynx, forms its upper and anterior part, produces at the upper part of the neck, a prominence called Adam's apple. It is an oblong quadrilateral plate, more broad than high, and composed of two lateral halves, which unite forward on the median line, where the angle they form is more acute in the male than in the female. Hence this layer is very convex forward and very concave backward, where it is open. superficial grooves, separated by a median prominence. The posterior edges are loose ; they extend upward and downward into two elongated horns, which are rounded and turned backward, and which are distinguished into upper and lower. The upper horns are longer and thinner than the lower. We observe on the outer face of the cartilage at the base of the upper horn a considerable triangular prominence, whence arises an oblique line which descends from behind forward to the lower edge, and which separates the posterior sixth of each half of this external face of the five anterior sixths. § 2251. The cricoid cartilage (C. cricoidea, s. annularis ), which forms the lower part and a portion of the posterior part of the larynx, is circular, as its name indicates, and about three times higher posteriorly than anteriorly. It is convex forward, and on the sides are depressions which render the surface corrugated, and on its upper edge is a sharp prominence which inclines outward. The posterior part is irregularly quadrilateral and broader below than above. Its anterior face is uniformly concave ; the posterior is loose and very prominent in the centre, especially below. § 2252. The arytenoid , triangular , or pyramidal cartilages (C. arytœnoideœ , s. triquelrœ , s. pyramidales ) have an elongated triangular form. Their anterior face is convex and uneven, and divided by a transverse prominence into a superior and an inferior depression. § 2253. On the summit of each arytenoid cartilage is a much smaller, and also triangular cartilage, termed the tubercle of Santorini, or the round or horny cartilage (corniculum, s. capilulum Santorinianwn),(l) the convex face of which looks forward, and the internal backward. Its lower face is concave, rests on the convex summit of the preceding, and is articulated with it by a loose capsular ligament, some fibrous ligaments of which add to its solidity. V. CUNEIFORM CARTILAGES. § 2254. The cuneiform cartilages (C. cunéiformes ) are slightly curved on themselves. Their bases are turned upward, and their summits downward. They are situated in the centre of the membranous expansion extended between the arytenoid cartilages and the epiglottis. VI. EPIGLOTTIS. § 2255. The epiglottis ( epiglottis , s. ligula ), a very soft cartilage, is nearly rhomboidal ; its lower part is pointed, and terminates by a superficial groove, and is situated directly above the groove of tlie upper edge of the thyroid cartilage. Its length exceeds its breadth, and it is much thinner from before backward than in any other direction, except at its centre. It presents numerous openings, through which penetrate small muciparous glands, which open on these two faces. Its elasticity, and the ligaments to be described, cause it generally to he perpendicular, and to rise towards the isthmus of the fauces : but the weight of the substances which pass on it, and the action of special muscles, depress it, so that it covers the entrance of the larynx. The epiglottis prevents the entrance of foreign bodies, especially the food and drink, from the cavity of the nose, and particularly the mouth, into the larynx. Although pathological observations, in regard to the absence of this cartilage,(l) and experiments, where deglutition has not been impeded by removing the epiglottis, when the nerves and muscles of the glottis were preserved, while it was very difficult when these nerves were divided, the epiglottis remaining entire ;(2) although all these facts(3) prove that the closing of the glottis also partially contributes to prevent the food from falling into the larynx, it does not follow that the epiglottis does not fulfill the function attributed to it by every physiologist since the time of Aristotle. This function, in regard to which we quote a lively, but perfectly correct remark of Casscrio,(4) has been doubted by Magendie, whose opinion has been contested by Mayer, from observations carefully made upon himself.(5) trary to Magendie’s assertion, that removig the epiglottis always rendered deglutition difficult in those animals where it wa3 removed. On this subject, Rudolphi mentions the case of a man who died of laryngeal phthisis, in whom the epiglottis was destroyed so that but a small portion of its base remained. This man found it very difficult to swallow: he was obliged to mix drinks with his food to form akind of pulp, which was introduced into the stomach with difficulty. G. Sachse relates several cases, which prove that deglutition is always very much impeded in laryngeal phthisis. (Beiträge zur genauem Kcnntniss und Unterscheidung der Kchlkopfs-und Lujtrührcnschwindsuchlcn, Hanover, 1821). Farther, Rudolphi attributes to the epiglottis another use also : he thinks that this cartilage serves also in those animals who breathe through the nostrils, the mouth being closed, to favor the entrance of the air into the larynx, by presenting a more direct way than through the cavity of the mouth. F. T. § 2258. The middle crico-thyroid ox pyramidal ligament (L. conoideum , s. thyreo-cricoideum medium ), is short, fibrous, strong, and triangular. Its base looks downward, and its blunt summit upward. It fills the space between the centre of the lower edge of the thyroid cartilage, and that of the upper edge of the cricoid cartilage. § 2259. The lateral thyro-cricoid ligament (L. thyreo-cricoideum laterale ) is loose, composed of fibres, which are oblique from above downward, and situated between the lower horn of the thyroid cartilage and the lower articular facet of the cricoid. § 2260. The middle thyro-hyoid ligament ( L . thyreo-hyoideum medium) is a broad layer of compact cellular tissue, which descends from the posterior edge of the body of the hyoid bone, to the middle groove of the upper edge of the thyroid cartilage. from the summit of the upper horn of the thyroid cartilage, to the extremity of the great horn of the hyoid bone. At about its centre, but generally nearer the upper than the lower edge, it contains a small rounded and oblong cartilage, or bone (C. tritica), which, in fact, belongs to the class of the cartilages or bones of the tendons. C. LIGAMENT BETWEEN THE CRICOID AND ARYTENOID CARTILAGES. § 2262. Each arytenoid cartilage is united by its lower face to the upper articular facet of the cricoid cartilage, by a loose synovial capsule, strengthened at intervals by ligamentous fibres. § 2264. The epiglottis is united to the upper edge of the middle hyoid bone by a compact cellular tissue, termed the epiglotti-hyoid ligament (L. epiglotti-hyoideum) . § 2265. The thijro-epiglottid ligament (L. ihyreo-epiglottideum ) is strong and fibrous. It extends from the lower extremity of the epiglottis to the groove in the upper edge of the thyroid cartilage. § 2266. We find on each side, between the arytenoid and thyroid cartilages, one above the other, two ligaments, directed from behind forward, from above downward, and from without inward, which are situated some lines from each other, and are termed the thyro-arytenoid ligaments (L. thyreo-cinjlenuidea). § 2267. The inferior thyro-arytenoid ligament (L. thyreo-arytenoideum inferius ), is much larger than the upper, and is composed of very distinct fibres. It extends from the upper and prominent end of the anterior edge of the inner face of the arytenoid cartilage, to the lower These two ligaments are generally more developed in the male than in the female, and are termed the vocal cords, or ligaments of the glottis ( L . vocalia , s. glottidis ), and the fissure between them is termed the glottis (glottis, s. rima glotlidis). § 2268. The superior thyro-arytenoid ligaments (L. thyreo-arytenoideora superior um, s. vcntricula laryngis) are situated farther outward and upward, between the centre of the anterior face of the arytenoid car tilage, and the angle of the thyroid cartilage. Those of the two sides are more remote from each other, are looser and much less evidently fibrous than the two preceding. They are distinguished only because the mucous membrane of the larynx is reflected outward, and forms a depression between them and these latter. C. MUCOUS MEMBRANE AND GLANDS OF THE LARYNX. § 2269. The larynx is covered internally by a reddish and smooth mucous membrane, which is uninterruptedly continuous above with that of the cavity of the mouth, and below with that of the trachea. The outer face of this membrane contains muciparous glands, which vary in size, and are united in bundles. One of these glands, the a7'ytenoid (G. arytenoidea), is situated before the arytenoid cartilage. Another is larger, imbedded in the midst of fat, and is termed the epiglottid gland ( G. epiglottidea ) ; it occupies the space between the epiglottis, the tongue, and the hyoid bone. It opens by from twenty to thirty excretory passages, which pass through the epiglottis, and the origins of which are easily seen on the inner face of the mucous membrane and the epiglottis. § 2270. The mucous membrane forms on each side a considerable depression, termed the ventricle of the larynx ( ventriculus laryngis). This depression is situated between the superior and inferior thyro-arytenoid ligaments ; it is at most but one line deep; and two broad. It extends then much farther from before backward, than in any other direction, It is covered below by a considerable number of muciparous glands. § 2273. The sterno-thyroideus muscle (M. bronchitis ), is thin, oblong, and considerably contracted from below upward. It arises from the posterior face of the handle of the sternum, and the inner part of the posterior face of the cartilage of the first rib, ascends directly before the trachea, covered by the sterno-hyoideus muscle, and is attached by an oblique edge, formed of very short tendinous fibres, to the oblique line of the thyroid cartilage. It is generally blended at its outer part with the thyro-hyoideus muscle, and it is cleft in a greater or less extent. tremity, a transverse or oblique tendinous intersection. Sometimes there are two of these muscles placed one above the other.(l) It depresses the larynx, by acting on the thyroid cartilage. Its union with the following muscle causes it to depress the hyoid bone. . § 2274. The hyo-thyroideus muscle has an oblong square form : it gradually contracts from below upward, and at the same time becomes thicker in the same direction. It arises from the oblique line of the thyroid cartilage, directly above the upper edge of the preceding, and ascends along the outer part of the lateral face of the thyroid cartilage, to arrive at the great horn of the hyoid bone, and is attached to the anterior part of the lower face. It raises the thyroid cartilage and the larynx, when the hyoid bone is fixed, and depresses it when the latter is not fixed, so that it contributes by the first of these two actions, to produce acute sounds, and by the second to deglutition. figure is a slightly inequilateral square. It is covered by the sternothyroideus muscle, and is situated between the lateral faces of the thyroid and the lower edge of the cricoid cartilage. It arises from the lower edge and the lateral face of this latter. Its fibres are directed obliquely from below upward, and from before backward, and are often divided into two distinct fasciculi, an anterior and a posterior. It is attached by a short tendon to the lower edge, and the inferior horn of the thyroid cartilage. § 2277. The crico -ary tenoideus muscle (AI. crico-arytcnoides, s. dilatator glotlidis posticus ), is rhomboidal, and fills most of the posterior face of the cricoid cartilage. It arises from its whole extent, ascends from within outward, and is attached by a short tendon to the outer edge of the arytenoid cartilage. § 2278. The crico-arytenoideus l at trails muscle is small, and of an elongated triangular form. It extends obliquely from before backward, and from below upward, from the posterior part of the upper edge of the lateral portion of the cricoid cartilage, to the lower part of the outer face of the arytenoid cartilage. b. Arytenoides obliquus et transversus. § 2279. The arytenoides obliquus and transversus muscles being united very intimately, should be considered as forming a single muscle, the different layers of which do not follow the same direction. The oblique fibres form the two posterior and weaker layers. They arise from the lower part of the outer edge of the arytenoid cartilage, above the insertion of the crico-arytenoideus muscle, ascend obliquely towards the opposite side, and becoming broader and thinner, are attached to the outer edge of the arytenoid cartilage of the opposite side. cover those arising from the cartilage of the other side. The transverse fibres are partly covered by the preceding, and are attached by their two edges to the posterior face and the external edge of the two arytenoid cartilages. § 2280. The thyro-arytenoideus muscle (AI. thyro-arytenoideus) is very elongated ; it arises from the centre of the inner face of the thyroid cartilage, from the pyramidal ligament, sometimes also from the lower part of the epiglottis, goes backward and a little upward, and is inserted at the lower part of the outer edge of the arytenoid cartilage, directly above the upper extremity of the crico-arytenoideus lateralis muscle, with which it is blended. These two muscles draw the arytenoid cartilage forward, and thus contract the glottis from before backward. They diminish the extent of the glottis more than any other muscle. The fibres which go to the epiglottis, are inserted in this cartilage. § 2281. The thyro-epiglotticus, or the depressor cpigloilidis muscle, arises from the centre of the inner face of the thyroid cartilage, and is inserted on the lateral edge and the lower part of the epiglottis. F. NERVES OF THE LARYNX. § 2282. The nerves of the larynx arise from the pneumo-gastric nerve, and are the superior laryngeal and the inferior laryngeal or recurrent nerve. Both are distributed in the mucous membrane and in the muscles.(l) (1) Magendie (Physiologie, vol. i., p. 206) and Cloquet (Traité d' anatomic, vol. ii., p. 622) think the first of these nerves goes wholly or nearly so to the crico-thyroidei posticus and laterales muscles, and also to the thyro-arytenoideus. Hence, whether the different muscles contract or dilate the glottis, they receive all their filaments from one of these two nerves, and completely dividing or tying them, enfeebles the voice, which is entirely lost when both are divided. Kudolphi ( Physiologie , vol. ii., p. 376) remarks that this description is incorrect, and that we must adopt that of Andcrsch and Scemmcrring, whose neurology is followed by Meckel. In fact, the superior laryngeal nerve anastomoses by some twigs with the recurrent nerve within the larynx ; the two nerves send twigs also to the muscles which contract and dilate the glottis, and the recurrent nerve sends some to the crico-thyroideus muscle. Andersch (Tract, de nervis hum. corp. aliquibus, p. i., Koningsberg, 1797, p. 60) mentions a case where the two nerves did not anastomose in the larynx, but expressly § 2283. The mucous membrane of the larynx is extremely susceptible, on account of the great number of nerves which it receives, particularly in the region of the glottis. This sensibility prevents foreign bodies from entering the trachea, where they would inevitably cause suffocation. It is curious that it is so developed only at the upper paît of the air-passages, and that the mucous membrane of the trachea does not possess it. several functions. The general motions of the larynx vary its relations with the adjacent parts, according as it is drawn upward, downward, forward, or backward. The partial motions change the mutual relations of its constituent parts, and vary particularly the form and extent of the glottis. have already explained, which prevents the food from entering it. In speaking, the larynx rises in acute sounds, both to raise the thyroid from the cricoid cartilage, and thus to contract the glottis, and at the same time to tense its ligaments, so as to lengthen and contract the trachea. In low tones, on the contrary, it is depressed to produce opposite changes. speaking. In fact, in deglutition, the glottis is so contracted by the action of its constrictor muscles, that, even were the epiglottis absent, the food would not necessarily and constantly fall into the air passages. states that this is not the common' arrangement. When it may be as true that it is not, says Rudolphi, that the constrictor muscles and those which dilate the glottis receive distinct branches from the par vagum, what must we conclude ? One nerve causes the contractions in muscles which contract and those which dilate the glottis j it is then unimportant which these museles receive. But the fact that the same muscle receives twigs from the upper and from the lower nerve is very important, since the action may take place in one direction when a ligature or section prevents it in the opposite, and it is still more so as the pneumo-gasti ic nerve anastomosesabove and below with the great sympathetic nerve, and above with the glosso-pharyngeal, the accessory, and the hypogastric nerves, so that the inner nerves of the larynx certainly come from several different sources. F. T. cannot be formed, on account of an opening in the Irachea.(l) Farther, this is not surprising, since they coincide with analogous changes which supervene simultaneously in the trachea, of which the larynx must be considered the upper enlarged and more developed part. From Legallois’ experiments the closing of the glottis is the cause of rapid death in suffocation, which occurs in certain cases from dividing the pneumo-gastric nerve or the laryngeal branch, particularly in youth, as in such states the glottis always appears very much contracted.^) The fact is correct, but the mode of explaining it by the paralysis of the arytenoidei muscles is only partially true. The contraction and even the closing of the glottis from Ihe paralysis of the muscles to which the recurrent nerve is distributed, seems to depend rather on the predominance of the muscles, the nerves of which are unaltered, and therefore caused only in part by the paralysis. In fact in animals of a certain age, in which the operation is less dangerous on account of the size of the glottis, this opening is almost entirely closed after dividing the two recurrent nerves, while it is closed but imperfectly when the superior laryngeal nerves are cut, and the power of forming it is lost after separating all the nerves of the larynx.(3) At each tone the glottis contracts, and the more the louder the tone is. (4) The contraction occurs particularly from one side to ihe other ; sometimes also from before backward, and often in every direction at once. 1st. By the loss of voice, without any derangement in the respiration, when the trachea presents an opening through which the air enters and emerges in inspiration and expiration. 2d. By the diminution or the total loss of voice when some parts of the larynx, as the vocal cords have been destroyed, or the arytenoid or cricoid cartilages, or the laryngeal nerves are divided. rangement of the parts of the larynx. The voice is formed in the glottis, since the power of producing it is lost when the crico-thyroid ligaments are divided, and the removal of the upper half of the arytenoid cartilages and the longitudinal section (1) Bichat, Anat. descript., 1802, vol. ii., p. 405. — Legallois, Exp. sur !c principe de la rie, Paris, 1812, p. 198. — L. Mende, Lieber die Bewegung der Stimmritze beim Athemholen, eine neue Entdeckung ; mit beygefügten Bemerkungen über den. Nutzen und die Verrichtung des Kehldeckels , Gripswald, 1816. of the thyroid cartilage produces the same effect, which is always observed iu the contraction of the glottis in crying, as the destruction of the upper ligaments has no effect on the voice, and as these ligaments likewise are always too far from each other to contract the glottis(l) transversely. § 2285. We have now to determine how the voice is formed in this place. Some suppose it is owing to the vibrations of the air, as in a wind-instrument. (2) Others assert that it is produced by the vocal cords, as in a stringed instrument.(3) Finally, several have combined these two theories. (4) dilated or contracted by them. b. That when one of the vocal cords is tense and the other relaxed, they do not produce two different sounds, but one sound, the acuteness of which is proportional to the breadth of the glottis. c. That the tone does not change when we touch the vocal cords. d. That the contraction of the glottis is sufficient to render the tone more acute, and its dilatation to depress it, although the tension of the vocal cords does not change, and independent too of their form. (4) Galien, De vsu partium, vol. vii., p. 10. — Casserio, De laryngé, book ii., ch. xiv., De glottide. — Dodart, Mém. sur les causes de la voix de l'homme et de ses différens tons ; in the Mém. de Paris, 1700, p. 308. — Id., Supplémens aux mémoires sur la voix et sur les tons; same journal, 1706, p. 169 and 500; 1707, p. 83. — Dodart, however, attributes most influence to the vibrations of the air ; it is then difficult to understand why modern physiologists, even neglecting Fabricius of Aquapendente, should maintain that Ferrein’s opinion was the only one admitted, ana present the theory a3 new, and more so because Ferrein directly opposes the hypothesis of Dodart. 2d. By experiments which have proved that the extent to which the larynx was open had absolutely no effect, on the acute or grave character of the sound,(2) while, on the contrary, the tone became acute as the vocal cords were carried outward and extended by the air leaving the lung, and was lower when the ligaments were compressed ; that it is modified in the same manner when these ligaments are fixed on several points ; that the different tones are produced when the degree of tension of the ligaments varied ; finally, that similar phenomena occur when the ligaments of the larynx are entirely detached, except at their tw1 2 3 4 5 6 7 9o extremities,(3) Very probably the third opinion is most correct, although the experiments first mentioned prove, that the vibrations of the vocal cords contribute less to produce the voice than those of the air passing through the glottis ; they occur simultaneously, without being necessarily connected with speaking, and the more as the larynx and trachea vibrate very evidently when the air is blown in with force, although the voice js not necessarily produced. (5) vocal cords. § 2286. But although the voice forms in the larynx, panicularly in the glottis, the parts, however, before this opening, the epiglottis, the cavity of the month, and the nasal fossæ, also assist to form it. In fact Haller has refused to it, contrary to the opinion of Tam \-ry,(6) and Santorini, (7) all agency in phonation, not because it exists before the fetus possesses a voice, (8) but because this latter is formed in the larynx, consequently below the epiglottis, and because birds sing although deprived of it. (9) This view of the subject is supported by some experiments, which demonstrate that the force of the voice does not change, although we cut transversely between the larynx and the hyoid bone, draw the (9) Epiglottis cquidem nihil facial ad vocem.cum ea (rox) nat.a sit el perfecta qua m primvm aer ex glottidis rima prodiit el absque epiglotlide arcs suaviseime fçijiant (El phys., ). ix., pt. i., § v., p. 572). epiglottis outward, and thus place the glottis directly opposite the external wound : that the removal of the top of this cartilage has no influence on the voice generally,(l) and that its depression, its elevation, and even its entire removal, have no effect on the character of the sounds.(2) But these facts only demonstrate that the epiglottis is not absolutely necessary to phonation. Farther, the argument drawn from birds proves nothing, since their voice is formed in a lower larynx, and in them the epiglottis may be replaced by the whole trachea and by the superior glottis. Finally, several observations and experiments, made with great care, admit the conjecture that the epiglottis alone, or together with the soft palate, contributes materially to the changes in the volume, tone, and modulation of the voice, (3) since its situation, direction, and form experience changes like those remarked in this respect in the voice, and we have no authority for admitting that these phenomena result from other changes which occur in the larynx, an opinion probably professed by Ferrein,(4) since the new organ of voice he maintains can hardly be the soft palate.(5) In regard to the cavities of the nose and mouth we may remark, that the power and clearness of the voice are increased by its being retained in these two cavities, as is easily seen from the difference when the nose is stopped, or the pituitary membrane is swelled. oral cavity. The vowels are formed principally in the canal included between the tongue and the palate. Their differences depend almost entirely on those in the diameter of this canal, caused by the motions of the tongue. II. SEXUAL DIFERENCES IN THE LARYNX. § 2287. The larynx is one of the organs which presents most manifestly the differences of sex. That of the female is usually one third and sometimes one half smaller than that of the male ; all its constituent cartilages are much thinner : the thyroid cartilage also is even flatter, because its two lateral halves unite at a less acute angle. Hence why the larynx in the male forms at the upper part of the neck a prominence which is not visible in the female. From the same cause also the groove in the upper edge is much more superficial in this latter than in the male. III. DIFFERENCES IN THE LARYNX DEPENDENT ON AGE. § 2288. The sexual differences we are about to mention do not appear until puberty : until then the larynx has precisely the same form in the two sexes, and consequently the voice is nearly the same in both. In eunuchs it is small as in females.(l) This organ developes itself much more slowly than other organs, and not proportionally with them : it seems less regular in respect to its periods, so that the larynx is sometimes smaller in some children than in others who are younger, although the growth of the others corresponds perfectly to their age. The larynx, especially the glottis, generally continues small for a long time ; thus it differs but slightly in a child of three and one of twelve years of age. But the difference is suddenly so great at the period of puberty, that in the course of a year thè glottis doubles in breadth and length. (2) We, however, must mention here its unusual littleness, which depends on the permanence of its primitive formation, and which coexists with the destruction or imperfect development of the testicles, (3) the absence of the epiglottis, (4) the division of this cartilage, (5) the absence of the upper horns of the thyroid cartilage, (6) of the cricoid and the arytenoid cartilages, (7) which is very curious as it establishes an uncommon, resemblance between the larynx and the trachea : the The consecutive deviations of formation, (3) especially those dependent on mechanical injury, are much more common than the primitive. We must distinguish among them wounds in the larynx made by a cutting instrument in suicide. Wounds of the epiglottis are generally considered as fatal ; we however have one case before us, where this cartilage was entirely divided longitudinally, and also cut transversely in its right half ; but death did not ensue. This case is curious also as it proves what we stated above, that the epiglottis is not absolutely necessary to close the glottis. quent irritation and inflammation, on account of its great sensibility. Sometimes death occurs at the end of a certain time, being caused by the abundant granulations which completely obstruct the glottis, and which are formed in consequence of a wound which suppurates. (4) The arytenoid cartilage is partially separated by a cutting instrument, and thus hanging in the glottis, may cause death by suffocation, like any other foreign body. (5) § 2290. The mucous membrane of the larynx either alone or with that of other parts, particularly the cavity of the mouth and that of the trachea, is often inflamed. Sometimes there is effusion, apd an accidental membrane is formed, which more or less completely closes the glottis, and the patient is suffocated. In phthisis laryngea also ulcers often exist which destroy it in a greater or less extent, and cause abnormal adhesions between it and the pharynx. This state also may cause suffocation in more than one way. But the swelling alone of the inflamed parts, without any effusion or ulceration, may be fatal. (8) (2) Meckel, Handbuch der pathologischen Anatomie, vol. ii., pt. ii ., p. 140. The case cited by Otto (Path, anat., p. 223), of a larynx divided into three, does not refer to this, but to the trachea, which presented three branches instead of two (Sandifort, Exerc. ac., p. 65). to the bones. Among the new formations cysts are not unfrequent in this organ, although much less common than the preceding anomalies. Sometimes they belong to the class of hydatids ; there is more or less danger of suffocation from them by closing the glottis. C. FOREIGN BODIES. § 2291. As substances which pass into the stomach from the upper part of the alimentary canal must necessarily pass over the epiglottis, foreign bodies not unfrequently enter this organ, and thence pass into the trachea. This happens particularly when we talk while eating, as then the glottis is not closed. These foreign bodies soon occasion death by suffocation. A case however has been mentioned where a ducat continued two years in the larynx,(l) and another where a piece of a nut-shell as large as a finger-nail remained there seven years. (2) § 2292. The organs of respiration ( systenia respiralorium)(3) are the lungs, which communicate with the external air by the trachea. Beside the prolongations of the trachea, they are formed by the pulmonary arteries and veins, by lymphatic vessels, nerves, and cellular tissue between these two parts, and a serous envelop, the pleura. (1) RI. Malpighi, De pulmonibus epistol. I. et II. ad A. Borellum, Bologna, 1661. — Th. Bartholin, De pulmonum substantiel et motu distribe. Ace. M. Malpigkii de pulm. obs. anat., Leyden, 1672. — Helvétius, Observations sur le poumon de L’homme ; in the Alim, de Paris , 1718. — Wildrik, De f abrita pulmonum, Franekcr, 1761. — Wohlfahrt, De bronchiis vasisque bronchialibus, Halle, 174.8. — Hildebrandt, De pulmonibus, Gottingen, 1786. — Reisseissen, De pulmonum, structura, Strasburg-, -1803. § 2294. The lungs ( pulmones ) have the form of an irregular cone, the base of which looks downward and the summit upward. Their concave base rests on the diaphragm ; their very convex external face is turned towards the ribs ; the internal, which looks toward the heart, is corn cave. The anterior edge is blunt, the posterior is sharp. Each lung is divided into two triangular lobes, an upper, smaller, a lower, larger, by a deep groove which extends obliquely from above downward and from behind forward, and which passes entirely through it. Between these two lobes the right lung also presents a third, much smaller, which is situated forward, and contracts much from before backward. The left lung differs from that of the right side, as its lower edge presents a groove in which the lower part of the heart is situated. Considered as a whole, the lung is divided into three, five, or six lobes, irregular in form and volume, in the spaces of which proceed the blood-vessels and the lymphatics, but the surface of which is not uneven, or but slightly so. § 2295. The posterior edge of each lung is cleft in most of its length, and thus presents a depression, the upper half of which receives the bronchiæ, the blood-vessels, and the nerves, while the ligaments of the organ are attached to the inferior. The pulmonary artery is situated first entirely on the summit before the bronchia, and sends in this place a considerable branch to the lung ; but it is soon directed backward, and passes behind the bronchia. The pulmonary veins are found entirely forward and downward, excepting the smallest and lowest branches, which proceed behind the lowest ramifications of the bronchiæ. § 2296. The lungs are situated on the two sides of the heart. Each is inclosed in a special serous sac termed the pleura, with the parietes of which they are in perfect contact in every part, but do not adhere, except at the part where this membrane is reflected to cover their external face. § 2297. Among the different parts mentioned as composing the lung, the trachea is the base of the others, and also the most important, as the air passes through it to enter and emerge from the lung. § 2298. The trachea ( tracheia ct arteria aspera ) is a canal about four inches long and nine lines broad, which begins at the fifth cervical vertebra, below the larynx, and is covered only by some muscles, particularly the sterno-hyoideus and the sterno-thyroideus. It is situated exactly on the median line, passes directly before the esophagus, and descends directly into the chest, between the large vessels of the head. Thence it gradually inclines toward the right side, so that its left portion corresponds to the centre of the vertebral column, and divides at an obtuse angle behind the arch of the aorta, about opposite the third dorsal vertebra, into two lateral branches, termed bronchi or bronchiez. The right bronchia is generally eight lines broad, one inch long, and the left is about half an inch broad, and two long. The direction of this latter is more perpendicular than that of the other : it is situated between the descending vena cava and the azygos vein. The left turns below the arch of the aorta, and goes forward. Each bronchia is covered with the pleura, proceeds obliquely from above downward, and from without inward, toward its corresponding lung, and on arriving there, divides into a superior and an inferior bronchia, each of which proceeds to a lobe. The lower branch of the right bronchia also soon subdivides into two twigs, a superior, which is smaller, and an inferior, which is larger, for the middle and the inferior lobe. "These canals ramify extensively within the lung, and represent a tree, terminated in every part of the surface of the organ in culs-de-sac, along which are distributed all the other component parts of the lung. The final ramifications, which are the most minute, and terminate in a cul-de-sae, are termed the pulmonary cellules ( cellulce pulmonares). merous oblong spaces. It constitutes the outer face of the trachea, and adheres intimately to the subjacent mucous membrane. Its vessels are more numerous than those in the other fibrous organs, and thus it resembles the fibrous tunic of the arteries. § 2301. The fibrous tissue of the trachea and of its ramifications, inclose pieces of cartilage, placed successively from above downward, on the two faces of which it passes, and adheres intimately. It, however, does not cover directly the. surface of these cartilages, which are entirely developed by a special perichondrium. ferent parts of the trachea, and in its ramifications. In the trachea they form imperfect rings, open at their posterior part, which surround the anterior and lateral parts of the passage. These rings are about two lines high, half a line thick, and an inch and a half long. They circumscribe about the two thirds of the trachea when in its greatest state of distension, and more than three fourths of its circumference when it is collapsed. The number of its cartilages varies from sixteen to twenty. Their form is more regular and more constant at the centre of the trachea than at its upper and lower extremities. In most of this canal, they generally form rings of equal extent, and of about the same height. The first, on the contrary, is much higher than the others, and higher at its anterior than at its posterior part. This arrangement establishes rather a remarkable correspondence from before backward, between it and the cricoid cartilage, in which there is an opposite arrangement. fourth ring, either on both sides, or more commonly on one only. The lower rings, on the contrary, frequently present on one or both sides, a greater or less fissure, that is, one which sometimes extends to their lower extremity, and sometimes stops short of it. Frequently, but not always, we then remark on the opposite side, a small segment of an imperfect circle, which corresponds to one of the two halves formed by the division, or a ring cleft on the other side, which in some measure makes up for the want of symmetry. But we as commonly find there a common and perfect ring, or one which is partly divided in the same manner and on the same side. There are generally but eight in the right bronchia, while there are eleven or twelve in the left. As they approach the lungs, they become more irregular, and are divided or blended with the rings adjacent. The number of the cartilages suddenly diminishes very much within the lungs, so that the ramifications of the bronchiæ become more membranous there. But, at the same time, these cartilages lose their regular form : they cease to represent rings, and resemble layers which are irregularly quadrilateral, triangular, &c. Besides, we find them in all parts of the trachea. c. Muscular fibres. § 2302. The posterior part of the trachea is formed by a muscular membrane, (1) which is about half a line thick when it is contracted. This membrane is composed only of transverse fibres, which are attached to the cartilaginous rings, and to the fibrous tissue between them, so as to cover the inner face of these rings, and of this tissue about from one to two lines. Within the lung, where the cartilages are arranged irregularly, and distributed on the whole extent of the bronchial tree, these muscular fibres surround also the whole trachea. They increase inversely as the cartilages, and they can be traced farther than these latter. § 2303. The fibrous tissue and the muscular tissue of the trachea are covered in their whole extent by a thin mucous membrane, which forms a continuous sac, and adheres intimately to the adjacent parts. Its posterior face presents in the whole extent of the trachea, muciparous glands, arranged compactly, which are more numerous and larger at the lower part of the trachea, where it bifurcates, and in the portion of the bronchiæ and of the lungs. They are very near in these different parts, and they are frequently as large as a bean. sages penetrate. This layer extends uniformly on the portion of the trachea formed by muscular fibres, while the glands are principally collected between the cartilaginous rings, so that after removing these latter, we easily perceive the place they occupy by the spaces in the glandular layer. places. § 2304. The mucous membrane is the last part visible among those which contribute to form the trachea and its ramifications, although reason and observation unite to demonstrate that its irritability extends beyond the points where its muscular texture disappears. The most minute ramifications of the trachea, which are formed by a homogeneous substance, terminate in a cul-de-sac, and are not continuous, as Helvetius asserts, with the cellular tissue which unites the different organic parts of the lung. The trachea forms a hollow tree, the twigs of which communicate by the branches, and the lattemLof the trunks resulting from their union, but not by means of mucous iija sue existing between these ramifications. This fact is established by numerous dissections and experiments. The minutest twigs of the bronchial tree, when filled with air or any other fluid, present the same form and the same limits, either when examined with the naked eye, or with a microscope. If we fill a bronchia with air or any other fluid, so as to inject, for instance, a whole lobe, and one of the secondary twigs is afterwards tied, the part of the lung in which this latter is distributed remains swelled and distended, while that where the bronchial twig is not tied soon collapses. § 2305. The blood-vessels of the lungs are of two kinds. Most of the organ is formed by the pulmonary arteries and veins, the first of which carry venous blood, while the veins carry back to the left half of the heart this fluid, which has been changed by the action of the air into arterial blood, in the limit between the two systems. than the arteries are. § 2306. The second order of blood-vessels includes the bronchial arteries and veins ( vasa bronchialia), which are connected with the nutrition of the lungs. We have already mentioned their origin. These vessels are distributed in the substance of the lung, along the ramifications of the bronchiæ, rest on their surfaces, and surround them with numerous plexuses. After supplying the muscular and the fibrous tissue, they penetrate to the mucous membrane, into which they send numerous ramuscules to the membranes of the pulmonary vessels, to the surface of all these parts, below the pleura. It is very curious that the anastomoses occur, not only in this vascular net-work, but also between the considerable branches and twigs of the pulmonary and bronchial vessels. The bronchial veins even mostly empty into the pulmonary. Those of the roots of the lungs alone White in small trunks, which empty into the azygos vein, or the descending vena-cava, or into the subordinate twigs of the system of the veins of the body. and red blood communicate extensively in the substance of the lung. 2d. That analogous communications which appear in other parts as abnormal, as the termination of the coronary veins of the heart in the left ventricle, the insertion of one or more pulmonary veins into the ticna-cava, the origin of a great pulmonary artery from the descending aofhi, &c., are only a more marked development of this type. 3d. That in the cases where the pulmonary artery was obliterated or very narrow, and the subjects lived a long time, these anastomoses were probably large enough to carry the blood in the pulmonary arteries. In fact, the bronchial vessels were found very much dilated in a case of this kind.(l) c. Lymphatic glands and vessels. § 2307. We have already made known the most important facts in regard to the distribution of the lymphatic vessels in the substance of the lung, and of the lymphatic glands which exist along the ramifications of the trachea. § 2308. The nerves of the lungs arise from the pneumogastric nerve. They are very small in proportion, but very numerous, and they can be traced far on the ramifications of the bronchiæ. They are divided into two orders. Some are distributed in the bronchial tree, others in the pulmonary vessels. The first penetrate to the muscular and mucous membranes, the second surround the vessels and penetrate either into the substance of the great trunks, or into the capillaries. Some extend even to the pleura. separate and entirely distinct. The internal parietes of the external sac are not attached to the parietes of the pectoral cavity, but are turned towards each other, and form a septum which is directed from above downward, and from before backward, which divides the chest into a right and a left half. These two internal parietes, however, do not touch. They are separated in the centre, and in most of the septum they form, by the heart : backward, by the aorta, the esophagus, the azygos vein, and the thoracic canal ; forward by the thymus gland and the great vascular trunks. They are united in all these parts by very loose cellular tissue ; and are most remote from each other in their centre. That portion of the septum situated before and behind the heart, is termed the anterior and posterior mediastinum ( mediastinum anterius et posterius). The anterior mediastinum descends between the heart and the middle anterior part of the thoracic cavity. Its direction is not perpendicular, but oblique from left to right. Besides, it does not correspond perfectly to the median line, but is thrown a little to the left, for the anterior edge of the right layer is attached to the left edge of the sternum, and that of the left layer to the cartilage of the left ribs ; thence the mediastinum descends on the anterior face of the pericardium. The external layer of the pleura of each side, is reflected on itself, between the two mediastina, to pass on the lower and upper faces of the lungs. For this purpose, it contracts around the pulmonary vessels and the bronchiæ, and descends from the centre of the posterior edge towards the lung. Upward, forward, and backward, it contracts suddenly, and from all parts towards this point ; but we observe below, on each side, a considerable triangular prolongation, terminated by a lower semicircular edge, which begins at the diaphragm, and is attached to the posterior edge of the lower lobe of the lung. This prolongation is termed the right and left ligament of the lung ( l . pulmonis dextrum et sinistrum). That of the left side is much larger than that of the right. The pulmonary pleura covers the whole surface of the lung, even its lobes, but does not penetrate between these lobes, which are separated from each other only by cellular tissue. a. Absolute weight. § 2310. The sound lung of an adult male, with all the blood and the air it contains, weighs about four pounds. When removed from the body, the pressure of the external air, which had been prevented from acting on it, expels a considerable portion of this fluid which remained in it after the last expiration. b. Specific gravity. § 2311. Considered in itself, the substance of the lung is heavier than water, for the lungs of a child which has never breathed sink in this fluid. But when respiration has commenced the specific weight of the organ is less than that of water, as the air which enters there is not entirely expelled during expiration. We cannot even press it out from a section of the lung : for then, after rupturing the ramifications of the bronchiæ, it extends in the cellular tissue, so that at the end of the experiment the substance of the lung is still lighter than the water, although a little heavier than it was before.(l) g. Capacity. § 2312. The capacity of the lung is not the same in all periods of life. It varies much, according as the organ is distended at the end of inspiration ( inspiratio ), or in that of contraction, at the end of expiration ( expiratio ). employed to estimate it. In the first respect there are very great individual differences, which are mostly congenital, but which may be accidental, as when the lungs are but slightly used, for instance, in students. The capacity of the lung is determined by adding the quantity of air expelled during expiration with that which remains there after this act is completed. This calculation may be made in several different ways. and expiration in a fluid in which the individual is situated. 3d. We measure the quantity of the air inspired and expired, by inspiring from a vase which has been measured, and expiring into another, the capacity of which is also known, or by the last proof alone.(l) At present the estimates of the quantity inhaled and expelled at each respiration varies much, from three to forty cubic inches. In fact, Abildgaard estimates it at three inches ;(2) Wurzer(3) and Lametherie,(4) at eight or ten ; Keutsch,(5) between six and twelve ; Abernetby,(6) Lavoisier, Seguin, (7) and Davy, (8) at thirteen ; Borelli(9) and Goodwyn,(10) at fourteen; Kite, (11) Allen, and Pepys,(12) at seventeen or eighteen ; Herholdt,(13) between twenty-five and twenty-nine ; Cavallo,(14) Jurin,(15) Sauvages, (16) Hales, (17) Hal'er,(18) Chaptal,(19) Bell,(20) Fontana, (21) Menzies,(22) and Richerand,(23) between thirty and forty cubic inches. tion, the following circumstances are attended to : 1st. After expiration, as long as the chest remains closed and the lungs are not removed, these organs contain more air than when separated from the body, because they collapse after opening the chest, and thus expel the air they contain. (2) Neue Versuche über das Athmen und den Nutzen desselben ; in the Nordisches Archiv, für Natur -und Arzneywissenchaft , vol. i., pt. i., p. 2. — Abildgaard however asserts in another place (ibid., pt. ii., p. 206), that from two to seven, and sometimes even fifteen cubic inches enter. which remains in the lungs after expiration. 1st. After fixing the diaphragm as firmly as possible, the abdomen is tied and the lungs collapsed, by making an incision in the parietes of the chest, we fill the space between these paiietes and the organ with water, which it is asserted should be equal in quantity to that of the air expelled from the lung by the pressure of the liquid, and also that of the external air introduced into the chest through the parietes. 2d. On opening the lung the air is received from it in a bladder adapted to the trachea, and it is measured ;(1) the lung is then immersed in water, the specific gravity of which is about equal to that of distilled water, while its absolute wmight is known : the quantity displaced is weighed, and w'e determine the cubic quantity of air it still includes. From these two methods we may conclude the quantity of air remaining in the lung of an adult after a con plete expiration to be about one hundred and ten cubic inches. In fact, Gcodwyn has introduced from ninety to one hundred and twenty cubic inches of water in the space between the chest and the lung. In Allen and Pepys’ experiments, the quantity of air first collected was 31.580 cubic inches: the lungs, which weighed four pounds, and which from their weight occupied as much space as an equal quantity of water, displaced six pounds of the liquid, so that there still remained within them a quantity of air equal to an ounce of water, that is, 59.554 cubic inches. The total of these two sums gives a little more than ninety-one cubic inches, as the quantity of air remaining in the lung after expiration ; but we may admit it as about one hundred and ten, on account of the pressure of the water on the mass of the lung, and the higher temperature during life. If we add to these one hundred and ten cubic inches of air remaining in the lung after a common expiration, about thirty inches which leave the organ at each common expiration of a healthy adult, (2) we shall have one hundred and forty-five inches as the capacity of the lungs in common inspiration, so that the difference of capacity between the state of dilatation and collapse of the organ is about thirty-five inches. But this difference increases very much when the respiration being deeper, the lung is unusually dilated and collapsed, because more air enters and leaves the lung at each time. (2) We take this as the mean number : it seems to us that a lower estimate should be ascribed to an unusual smallness in the lung1 2, or to careless calculation, and that a greater estimate depends upon an unusual development of the chest, or on a very (leep respiration. Farther, we ought to mention that the air is dilated one sixth by the heat of the body. OF THE RE3PIRATORV STSTEM. Thus Seguin(l) inhaled in a very deep respiration one hundred and thirty inches of air, which would expand by the heat of the body to one hundred and fifty, so that then the capacity of the lung was equal to two hundred and sixty cubic inches. Kite estimates the capacity at three hundred cubic inches. On the other hand, Jurin expired two hundred and twenty cubic inches, (2) and Herholdt, 208.(3) If we admit here that these expirations took place after a full inspiration, we ought to reduce the capacity of the 'lung to fifty-two and even to forty cubic inches, which estimate perfectly agrees with that formed by Davy by another method.(4) In contrasting the estimates of Seguin and Jurin, and disregarding the diminution of the volume of the air expired, we find a difference of two hundred and twenty between the greatest dilatation and the greatest relaxation of the lung, that is, this latter state is to the other as 1 : 6.5. § 2313. The lung is not very sensible. Its transverse and its longitudinal muscular fibres, which are similar in their nature to muscles, give it the power of contracting, which, judging from experiments, (5) is exerted whenever its external or internal surface is stimulated, and which without stimulation(6) executes the motions which cannot be attributed to those of the parietes of the thorax, since they are simultaneous with these latter, and are observed when the parietes of the thorax are destroyed. (7) Consequently the air-passages contract actively during expiration ;(8) but all these phenomena, adduced to prove that the lungs possess a power of extension which allow them to dilate actively in inspiration, can be satisfactorily explained in another manner. (9) vol. ii., p. 134. (9) J. D. Herholdt, Ueber die chirurgische Behandlungen der Brustvrunden, veranlasst durch neue Versuche über den Mechanismus des Athemholens ; in the Nordisches Archiv., vol. ii., pt. i., p. 44-60. § 2314. The function of the lung is respiration, which consists essentially in the change of venous into arterial blood by the expulsion of carbon and the absorption of oxygen. The atmospheric air enters into the organ during inspiration, and emerges from it loaded with carbonic acid during expiration ; this change of the blood, and the cold produced by the evaporation of the water exhaled, are the most important functions of the lungs ; but the variations in its capacity also affect the circulation, for the blood circulates more rapidly from the right half of the heart into the pulmonary artery during inspiration, and from the pulmonary veins into the left portion of the heart during expiration. § 2316. The lung presents considerable periodical differences^ 1) in respect to its existence, situation, texture, color, contents, volume, and finally its absolute and relative weight. nancy. 2d. Situation. From the greater proportional volume of the heart and its slight development, the lung is situated much more posteriorly before than after birth, so that sometimes it is not seen at all on opening the cavity of the thorax ; consequently it covers the pericardium, and generally does not. entirely fill the sac of the pleura, and hence does not touch the parietes of the chest. 3d. Texture. At the third month of pregnancy we begin to distinguish the cartilaginous tissue in the air-passages of the lungs. The lobules are at first united by a looser cellular tissue than that com- (1) Meckel, Mémoire sur le développement du cœur et des poumons dans les mammifères ; in the Journ. compl. dessc. m éd., vol. i., p. 259. — Consult also on the difference in the lung- of the child before and after respiration, G. J. Schmitt, \eve Versuche und Erfahrungen über die Plocquetsche und hydrostatische Lungenprobe , Vienna, 1806. — A. Lccieux, Considérations medico-légales sur l'infanticide , Paris, 1011. — Magendie, Sur la structure du poumon de l'homme , sur les modif cations qu'éprouve celle structure dans les divers âges , et sur la première origine de la phthisie pulmonaire ; in the Journ. de physiol, expérim., vol. i., p. 78. — Fleischmann, Sur la formation de la trachée-artère ; in the Journ. compl. du diet, des sc. méd., vol. xvi., p. 141. — Id., De chondrogenesi asperiœ arterice et de situ oesophagi abnormi nonnulla, Erlangen, 1820. monly seen, and they are also formed of small subordinate lobes, so that here, as in other parts, as the muscles, the homogeneous mass is at first divided into its great subdivisions, but afterward into the smaller parts. 4th. Color. The color of the lung is at first reddish white in the fetus, and is whiter the younger the fetus is. This organ gradually becomes of a deeper red, in proportion as it is better supplied with bleed. After birth this tint is bright from respiration, and also becomes deeper. Contents. The trachea and its ramifications contain after birth only air, and a small quantity of aqueous vapor and mucus. But this is not true of the fetus, where it is filled with the fluid of the amnion. By the laws of hydraulics, when the fetus swims in this fluid it enters the trachea, without any respiratory motion on the part of the fetus. It usually escapes after birth, and when it does not escape at this time, which is rare, it may suffocate the child.(l) It does not acquire its normal proportional size till puberty. 7th. Weight. The absolute weight of the lung presents very remarkable periodical differences, which depend on the organ remaining inactive until after biith. In the fetus its specific gravity is greater than that of water, in which it sinks ; but when respiration has once commenced, as it is never free from the air which has entered in it, its specific gravity is less than that of the water, and it floats. § 2317. Most of the differences mentioned, especially those in regard to situation, volume, color, and specific gravity, appear more or less at birth, and result from respiration. The lung, becoming lighter from the effect of the air entering- it and which never entirely leaves it, occupies also more space after^-espiration, and is situated more anteriorly, covers most of the pericardium, and is in contact with the parietes of the chest. The deep red color communicated to it by the venous blood before respiration changes to a bright red when the new being breathes. Finally the organ, which when collapsed received less blood, and was consequently lighter, becomes heavier when after being distended by respiration, it is more permeable to the blood. Hence these differences have been thought sufficient to determine whether an infant was born living or dead. But as the specific oravity having diminished, the lung floats, which proof constitutes what is (1) P. Scheel , Commentatio de liquoris amnii asperice arteriœfœtuum humanorvm natura et usu ejusque in asphyxium neonatorum et medicinam forensem infiuxu Copenhagen, 1799.— Herholdt, in Reil, Arch.iv.fur die Physiologie , vol. iii., p. 163 — Id., in the Nordisches Archiv., vol. i, p. 212. termed the test hydrostatica ;(1) as also the afflux of the blood increases the absolute weight of the organ, and its relative weight compared to that of the body constitutes another kind of proof, termed the test by the balance, (2) this principle has been laid down, that when the lungs of a child swim in water, and a similar or analogous proportion exists between the relative weight of the lungs and that of the body, it is established that this child was born alive and that it breathed. 2d. The lungs may also swim from the fact that the air has been pushed into them, through the mouth or nose, either while they continued in the thorax, or after their removal from this cavity. Putrefaction also may give rise to the same result. 3d. Several experiments demonstrate that respiration does not necessarily cause in the lungs the above mentioned changes. Some parts of a lung, or even an entire lung, have been seen which did not swim in water, although the child has lived, breathed, and cried, not only for several days, (4) but even for six weeks. We have seen in a child six weeks old all the middle lobe of the right lung, and in another four weeks old, great portions of the same lobe apparently healthy, which were absolutely incapable of floating. The left' lung is most frequently retarded in its development, which peculiarity doubtless depends on the fact that the right bronchia is much shorter and broader than the left, so that usually, even in children who died soon after birth, the right lung floated, while the left floated very imperfectly, or not at all.(5) It is at least very rare that the contrary occurs. a. The rarest case is when the cause of the sinking of the lung depends on a morbid alteration in its texture, an effusion, an induration, for these are very unfrequent before birth, and even when they occur to a great extent, the organ does not acquire a greater specific gravity than that of water. b. A more common cause is the presence of foreign bodies, especially mucus, and the fluid of the amnion in the trachea, or the feebleness of the fetus, all which circumstances render the dilatation of the lung imperfect. c. We must remark also that this change in the specific gravity supervenes gradually, and when the respiration takes place with the requisite degree of strength, as in the beginning, and when the child respires but feebly, it extends to some parts of the lung only, and sometimes it is not produced at all by the first inspirations. 4th. Sometimes, although the child has not breathed, the lungs have an absolute and consequently a relative weight, in proportion to the body, as great as when the child has respired. There are some cases where the relation between the weight of the lung and the body is still greater, for instance, as 1 V15A, to 29ff, to 33f, to 32^f, to 34t735t,(1) although respiration did not take place. more blood than usual. 5th. Observation likewise proves that the lungs of infants born alive are sometimes proportionally lighter than those of still-born children are, according to the preceding estimate, (2) as they are found in the proportion of 1 : 77T9T, to 77if, and to 104. § 2318. Primitive deviations of formation. The lungs present proportionally but few anomalies resulting from a primitive deviation of formation ; they however sometimes manifest them in respect to quantity and quality. naître, le poumon droit respire avant le gauche ; in the Mém. de Paris, 1765. — Some writers have attributed this discovery to Petit, but wrongly : he mentions only one case (Mém. de Paris, 1753), and does not point out the real cause of the phenomenon. and also occurs in subjects whose formation is otherwise normal, and resembles the normal singleness of the lung in several serpents. The absence of the trachea is less common than that of the lungs ; when it occurs the lung is situated next to the larynx, as also in several reptiles. c. The smallness of one or of the two lungs. The first anomaly is generally produced mechanically by an external obstacle, particularly the presence of the abdominal viscera in the cavity of the thorax in a subject affected with diaphragmatic hernia. The second, which is generally connected with narrowness of the thoracic cavity, depends on a primitive dynamic anomaly of the formative power, and sometimes occurs in individuals otherwise well formed, and sometimes is attended with other deviations in formation, arising from suspended development. d. We ought also to mention here the exposure of the lungs or trachea sometimes observed, since it depends upon the formation of the parietes of the thorax being arrested at one of the early periods through which it successively passes. 2d. Congenital deviations in form relative to the quality are : a. The abnormal division, which is indicated in the lungs by the presence of an unusual number of lobes, or by the deeper separation of those always existing, and in the trachea by its division into three branches. This last anomaly, judging from facts hitherto collected, occurs only on the right side, and is curious as a repetition of the peculiar structure of the ruminantia and the cetaceous animals. Consecutive deviations of formation. The pure consecutive accidental deviations of formation are particularly wounds, which often suddenly cause death, on account of the considerable caliber of the vessels, but sometimes death occurs from the dangerous inflammation and suppuration of such important organs ; but they are not necessarily nor always fatal. We must mention here the abnormal communication with the other cavities, which sometimes occurs when the parietes are destroyed ; the most remarkable is that which occurs in aneurism of the aorta. (2) 1st. Inflammation, generally termed pneumonia , bronchitis , and pleuritis , according as the whole substance of the lung, the mucous membrane of the trachea, or the pleura, is affected.(l) The most usual consequences of pneumonia are : a. Thickening and induration of the tissue of the lungs, from an effusion often existing in a great degree, and then forming the state termed hepatization ( hepatisatio)(2 ) The substance of the lung is then generally homogeneous, friable, brittle, grayish white, much thicker in texture, and sometimes - possesses a specific gravity greater than that of water. 2d. Suppuration Pus usually burrows for itself a passage into the bronchiæ. More rarely it is effused into the chest, constituting empyema, or into the adjacent organs, as the pharynx or the aorta.(3) Bronchitis terminates sometimes by suppuration, sometimes by the formation of solid or hollow membranes, which fill this cavity and rarely adhere to its inner face. Very probably, however, the development of these accidental membranes is not always and necessarily preceded by an inflammation of the trachea. (4) The consequences of pleuritis are : (1) C. Hastings, A treatise on inflammation of the mucous membrane of the lungs, London, 1820. — T. Alcock, Observations on the inflammation of the mucous membrane of the orga ns of respiration, London, 1820. (3) V. Laennec, De V auscultation médiate, vol. i. — Andral, Clinique médicale, vol. ii. — Louis, Observations relatives à la perforation du parenchyme du poumon ; in the Archiv, gén. de mcd., vol. v.j p. 321. — Bouillaud, Nouvelles observations sur la gangrène des poumons ; in the Revue médicale, vol. iv., p. 375. Bayle, and since enlarged upon by Andral, that sometimes in individuals affected with chronic bronchitis, even with an expectoration of pus, the mucous membrane is. hardly rosy or even perfectly white in its whole extent. But ought not we then to admit that the tissue is discolored after death 1 Farther, it is remarkable that the softening and ulcerations are much more rare in the mucous membrane of the bronchiæ than in that of the intestine, and that the frequency of the ulcerations decreases from above downward. The inflammation of this membrane frequently terminates also in thickening, which causes the contraction of the bronchiæ. Hypertrophy even sometimes extends more or less to the external fibrous and cartilaginous tissues. We must not confound the contraction of the bronchiæ, which results from it, with that which comes from the compression of these canals by a tumor, among others by tumefied ganglions, which are rather common in children, or by au aneurism of the aorta. Chronic inflammation results also in a dilatation of the bronchiæ, to which Laennec first attracted attention, and which has-been studied very carefully since by Andral, as have also the different alterations in the secretion of the mucous membrane of the bronchiæ. Consult on this subject : Lacnnec, De l' auscultation médiate, Paris, 1819, vol. i., p. 124. — Andral, Observations sur quelques altérations organiques des bronches ; in the Archiv, gén. de méd., vol. iv., p. 514.— Id., Clinique médicale, vol. ii., p. 1-85. — Bree, Recherches sur les désordres de la respiration, Paris, 1819.— Desruelles, Traité théorique et pratique du croup, Paris, 1824. F. T. a. Thickening, induration of this membrane. b. Effusion of serum, which when not coagulable in a great degree, causes hydrothorax, and which when coagulable produces the mutual adhesions of the contiguous surfaces of the pleura.(l) The principal new formations in the lungs are tubercles. 3d. The repetitions of the normal tissues in the respiratory organs are rare. We must however refer to this the accidental membranes developed after pleuritis, because they are repetitions of the cellular tissue and the accidental ossifications(2) formed in the osseous tissue. These ossifications frequently appear as thin elongated laminæ, situated on the outer face of the pleura. They are more rare on the inner face of this membrane, in the form of rounded bodies, which at first adhere, but are finally detached. The pretended change of the pulmonary substance into cartilage is probably in most cases only an induration resulting from effusion. Sometimes however cartilaginous tissue is really developed accidentally in the lungs. CAVITY OF THE THORAX. § 2321. The thoracic cavity contains, besides the lungs and their vessels, the heart, the commencement of the aorta, the trunks of the ascending and descending venæ-cavæ, the azygos vein, the thoracic canal, the esophagus, and the thoracic portion of the ganglionnary nerve. We have mentioned previously the manner in which it is formed like a cage. Its upper extremity is generally the narrowest and its lower extremity the broadest part of the chest : at least it is~ generally much broader at its base than at its summit. It is convex, on the sides, flattened forward, larger from above downward, and shorter from before backward than in any other direction, much longer posteriorly than anteriorly, and provided below with a more or less convex floor which is formed by the diaphragm. Posteriorly the bodies of the dorsal vertebra imperfectly divide it into two halves. the prominence of the liver. The inner face of its parietes is covered in nearly its whole extent by the external layer of the pleura, which is there attached to it by a very short cellular tissue. Of the organs it incloses, the lungs and the heart are united to it by its surrounding serous membranes ; the others directly by cellular tissue. I. MOTIONS OF THE CHEST, § 2322. The chest is continually extended, enlarged, contracted ; and the first state occurs in inspiration, and the second in expiration. The motions of the chest which determine them, produce a simultaneous dilatation and contraction in the air passages. The lung, being compressed when the chest collapses, expels the air within it, while it enters through the mouth and nose, when, the chest dilating, the obstacle from the collapsing of its parietes no longer exists. expiration, occur in every direction. The greatest change is that in height. It depends partly on the depression of the diaphragm in inspiration, and its rising in expiration, partly also on the raising of the ribs by the intercostales and scaleni muscles. being drawn outward. The parietes of the chest follow exactly the motions of the lungs during respiration, and these two parts remain in contact, at least in the regular state, during expiration or inspiration, so that they are found in perfect contact after the strongest of all expirations, that which occurs at death. § 2323. The chest of the male is much larger than that of the female, as it is longer, broader, and deeper. Its capacity is also more uniform, so that it is proportionally a little broader, rounder, and more movable. The bodies of the dorsal vertebrae do not project as much, § 2324. The chest is proportionally the smallest of the three sphlanchnic cavities of the body during the early periods of existence, which depends particularly on the slight development and the inactivity of the lungs. It possesses in the same proportion a greater degree of elasticity, because the costal cartilages are much longer in proportion to the ribs, than during the successive periods.(l) § 2325. Sometimes the chest is only partially closed, from a primitive deviation of formation. When this anomaly exists on the anterior face or the sides, the internal organs are exposed ; when in the lower wall, the abdominal and pectoral cavities abnormaly communicate, and some of the thoracic viscera enter the cavity of the abdomen. The same also may be caused later by wounds, ulcers, &c. A common congenital deviation of formation is the abnormal smallness of the chest, which generally attends a corresponding defect in the development of the lung, and a disposition to tuberculous phthisis. The alterations in the texture of the chest are principally different kinds of tumors, which occur in the mediastinum. These tumors sometimes become large, and compress the organs in the thoracic cavity so much, that the subject dies from the suspension of the circulation or nutrition. (2) AND RESPIRATION. § 2326. We find near the organs of voice and respiration, two imperfect glands, (3) the thyroid and the thymus glands, which are similar, not only as they both present the general characters of glands of their species, but also because they are situated directly on the median line, behind the anterior face of the body, before the organs of respiration, and because they even touch in the early periods of fetal existence. These two glands possess numerous blood-vessels and lymphatics. They have no excretory ducts, but contain in their spaces a fluid different from their substance, and which is very evident in the thymus gland. The change of a considerable quantity of blood, which is pro- (3) P. H. Bœcklen, De thyroideœ, Ihymi et glana lularum sùjnarenaliumfunctionîbus, Strasburg1 * 3, 1753. — J. F. Meckel, Lieber die Schilddrüse, Nebennieren und einige ihnen verwandte Organe ; in his Abhandlungen aus der menschlichen und vergleichenden Anatomie, Halle, 1816, p. 1-277. bably peculiarly modified, and the formation of their fluid, are the only functions which can be assigned to them with certainty. We then have reason to think their functions in the sanguineous system are analogous to those of the lymphatic vessels, that is, they are organs which contribute to perfect the formation of blood. This conjecture is rendered probable from the fact, that the blood which passes through their tissue, and the fluid which they prepare, soon enter the venous blood near its entrance into the lung. and on the sides of the upper part of the trachea and pharynx. It is composed of a centre, which is slightly contracted, thin, and about four lines high, termed the isthmus , and of two lateral portions or horns, which are directed from below upward, and terminate in a point. The central part is situated directly below the larynx, and before the three or four upper rings of the trachea. The two horns extend below to the sixth or seventh ring, and above to the lower horn of the thyroid cartilage. There is generally detached more or less from its centre, a median horn, which is generally single, rarely double, termed by Lalouette the pyramid. This horn is rarely perfectly cylindrical, and generally corresponds to the left side more than to the right, (2) which deserves to be remarked on account of the greater development cf the hyoid bone, generally occurring on the same side. It reascends before the thyroid cartilage to the middle hyoid bone, and it terminates there, gradually becoming thinner. This horn exists more frequently than it is deficient. (3) We must then attribute to accident, or to careless dissection, the assertions of authors to the contrary. (4) § 232S. It is generally surrounded by a special and unmated muscle, the levator gland, thyroideœ muscle, the upper extremity of which is generally attached to the body of the hyoid bone ; sometimes it does (1) P. Evertze, De glandulâ thyroideâ, Leyden, 1708. — Santorini, Obs. anat., ch. vi-xvii.- — Duvernoy, Obs. anat., 2, 3, 4 ; in the Comm. Petrop., vol. vii. 1740, p. 216218. — Lauth, De glandula thyroideâ, Strasburg-, 1742.— Morgagni, Ep. anat., Venice, 1763, vol. ix.'§ 30^10. — Uttini, De glandules thyroideœ usu : in the Comm. Bonon., vol. vii. p. 15-23. — Lalouette, Recherches anatomiques sur la glande thyroïde ; in the Mem. prés., vol. i. 1750, p. 159-175. — Gunz, Obs. anat. I. sur la glande thyroids, ibid., p. 283-284. — Schmidtmuller, Leber die Ausfuhrungsgange der Schilddrüse, Landshut, 1804. — B. Hofrichter, Mémoire sur la thyroïde, in the Journ. compl. des sc. méd., \ ol. x. p. 21. tilage. In the latter case the middle horn is very slightly developed. This muscle participates in the asymmetrical arrangement of the middle horn of the thyroid gland, so that it generally belongs to the left half of this latter, more than to its right portion : it however is not always attached to the same side of the hyoid bone, or of the thyroid cartilage, but sometimes passes obliquely before the trachea or the larynx, to arrive at the opposite side. This arrangement, which apparently renders it still less symmetrical, although it really tends to re-establish the symmetry, occurs particularly when it is attached to the thyroid cartilage, and is then inserted in its inner edge, on the outside of the crico-thyroideus muscle. § 2329. Each of the lateral horns is generally two inches high, while the height of the isthmus is only one inch. The entire breadth of the gland is about eight inches ; that of each horn is nine lines. The whole gland weighs about one ounce. 2330. The thyroid gland is of a dirty red color; its texture is firm and solid, its surface is smooth. It normally contains no cavity ; however, when we make an incision, either into the lobes or between them, a fluid analogous to the serum of the blood, oozes in great abundance from the wound. Several anatomists, as Vater, (1) Santorini, (2) Coschwitz,(3) and Schmidtmuller,(4) have thought they saw one or more passages which extended from the gland into the larynx or trachea. They have attempted to consider the middle horn as an excretory canal, both from its form and the openings in the larynx on a level with its upper extremity. But the observations in support of this opinion are so trivial, and the most distinguished anatomists who have made them, have thought them of so little importance, that as yet we have reason to consider, with Duvernoy, Morgagni, and others, the thyroid gland as having no excretory passage, or none except the lymphatic vessels. As the thyroid gland is proportionally much larger during the early periods of life, and as particularly its middle horn is then much more developed than in the adult, perhaps the excretory canal exists at this period, and is obliterated as the development of the gland is arrested, so that the imperfect development of the glands from a deviation in formation, often results from the absence or obliteration of their excretory passages. § 2333. The thyroid gland is at first formed of two separate glands, one of which is much larger proportionally than it is when the body is entirely developed, softer, more vascular, and consequently redder. Its middle horn, particularly, is much larger than it is subsequently. § 2334. The thyroid gland is sometimes, but very rarely, as Morgagni has remarked, (1) divided into two distinct and separate halves. This anomaly is very remarkable on account of its relations with the state of the organ in the early periods of fetal existence, and because it occurs normally in most mammalia. An arrangement resembling it, is the considerable narrowness of the central portion or of the isthmus. Sometimes only a portion of a lobe is separated from the rest of the gland. (2) Rather a common deviation of formation, but which is most generally consecutive, and rarely congenital, is the enlargement of the thyroid gland, which constitutes goitre ( struma ) ; this is frequently enormous, and is endemic in the narrow valleys of mountainous countries: The goitre, however, by no means always depends simply on an increase in the size of the thyroid gland : it is frequently only a consequence of the development of new formations in the tissue of this organ, or at least presents a conplication of the two states. Hypertrophy of the thyroid gland, when not endemic, is much more frequent in females than in males. It appears particularly at puberty, (3) gestation, parturition, and lying in. The abnormal formations occurring in the thyroid gland, are principally repetitions of normal organic elements, as serous cysts filled with different fluids, also cartilages, fibro-cartilages, and bones : all these formations frequently coexist. § 2335. From what precedes, it follows, as we have already remarked, that in its situation and form, the thyroid gland is'a repetition, in the upper half of the bodj», of the uterus and prostate gland. This (3) Journal de médecine de Sédillot, vol. lvii. p. 416. We there read the remarkable case of a boy fourteen years old, in whom the thyroid gland was so much swelled, without any external cause, as to produce suffocation. § 2336. The thymus gland ( Gl . thymus , s. corpus thymianum)(\) is an irregular square or quadrilateral body, the base of which looks downward, and the summit upward, which occupies the upper and anterior part of the anterior mediastinum, where it is situated directly behind the sternum, before the base of the heart and the large vessels. It as'cends also more or less out of the chest for about half an inch, and extends on the anterior face of the neck, where it is covered by the sterno-hyoidei and sterno-thyroidei muscles. Its height and breadth much exceed its thickness. Its length generally exceeds its breadth. Although it gradually contracts towards its summit, it however generally presents a more or less considerable prominence at its upper extremity. Its vessels, which are not very large, arise anteriorly, enter it from above downward, from behind forward, and from before backward. But each of its lobes has not a special trunk, and receives vessels from several regions at once. § 2338. Beside an external envelop, which is given to it by the anterior mediastinum, the thymus gland has still a less dense or less solid proper cellular capsule, below which the fat collects here and there in corpulent persons, but does not accumulate in any great quantity. After removing this capsule, the thymus gland is itself divided into a right and a left half. Its two lateral lobes are attached only by very loose cellular tissue, and by the vessels which penetrate them, so that it would be more correct to admit two thymus glands. These two halves, which are also triangular, and the two internal faces,- are situated one against another in their whole extent, are similar in form and volume, but are not exactly alike : one of them is sometimes about one tenth larger and heavier than the other. The external envelop of the thymus gland will show that its surface is not smooth and uniform, but divided into several larger and smaller lobes, which are composed of smaller lobules, separated less deeply from each other, between which the two external envelops do not (1) G. E. Mctzg-er, Hist. anal. med. thy'mi, Tubingen, 1679. — G. H. Muller, De glandula thymo, Leyden, 1705. — Verheyen, Dc tliymo, Leyden, 1706. — G. Bidloo, Defens, exer de thymo , Leyden, 1707. — J. G. Duvernoy, in the Comm. Petrop., vol. vii.— A. L. de Hugo, De glandidis et speciatim de thymo , Gottingen, 1746. — G. Hewson, Experimental inquiries , part iii. London, 1717. — Lucse, Anatomische Unter* su/hungen der Thymus in Menschen und Thieren, Frankfort, 1811-12, are united only by a loose cellular tissue and by vessels. § 2339. On cutting the thymus gland, there flows out spontaneously, or by pressure, a fluid, differing from its own substance, more or less abundant, thick and whitish, similar to that which exists in the ruminantia, between the fetal and maternal portions of the placenta. Many anatomists assert there is no cavity in the gland, and this fluid is consequently contained in its substance. Others think that the lobules alone are really hollow. Finally, some admit a great cavity the parietes of which are formed by the substance of the organ. We maintain the latter opinion : for in examining very recent thymus glands, we have several times observed either on cutting them or slightly inflating them, a large cavity in each of the two lateral lobes. This cavity is lined by a thin and smooth membrane. It communicates with those in the lobules, and contains a great quantity of the fluid mentioned above. Sometimes, however, this cavity is less apparent, so that very possibly the internal arrangement of the thymus gland is not always perfectly the same. Thus, in some cases, the lateral cavities are divided into several compartments by intermediate septa. Sometimes, however, we find the arrangement maintained by the partisans of the second opinion to be constant, and to which the preceding imperceptibly leads. Its upper part appears first, and it enlarges from above downward. Although it is not proportionally as large until the end of the first year, and sometimes even till that of the second, it continues to grow during all this period in the same proportion as in the full grown fetus. But at this period it wastes, its vessels contract, and the fluid it secretes diminishes. It disappears in a direction opposite to that in which it was formed, that is from below upward. by fat. From this we may conclude that it does not exist except for about the fifth part of life, and that the energy of its function declines long before it disappears. Its most flourishing period is -consequently very different from that at which most other organs have attained their greatest development. § 2341. We have already mentioned in a general manner its functions : several circumstances lead us to think it is very intimately connected with respiration, and more or less replaces it. We may, however, easily reconcile the two conjectures, since from what we have said above, the use of the thymus gland, is to prepare for the perfect formation of the blood by respiration. which is generally observed in acephalia vera. Its smallness, when the organ is perfectly developed in respect to the number of its parts, is commonly attended with a languid state in nutrition generally. We have sometimes seen this anomaly also in acephalia falsa. Its continuance at the degree of development which characterizes it in the early periods of life, sometimes attends abnormal formations of the heart, and those states of the lungs which prevent the perfect formation of the blood. (2) This then supports our opinion advanced above in regard to its functions. As this organ disappears very early, alterations in its texture are proportionally rare. We may, however, mention as such, different kinds of tumors, although in many cases those mentioned by authors are developed only in the place occupied by the thymus gland, and after it has disappeared. (3) G. Bendt, Defabrica et usu viscerum uropoeticorum, Leyden, 1744. — J. Fantoni, De renibus et primum de succenturiatis, de ureteribus et vesica, Turin, 1745. — A. Richerand, Mémoire sur V appareil urinaire ; in the Mém. de là soc. méd. d'émul. vol. iv. p. 303. viz. the kidneys, the ureters , the bladder, and the urethra. The last three organs may be opposed to the first. These are entirely excretory organs, for they carry nothing which can be useful to the organism, remove from the body an excess of azote, which is the base of the most essential constituent principle of the urine, the urea , and correspond in form and situation in. the lower half of the body, to the respiratory organs in the upper. § 2344. The kidneys (renes),( 1) the most essential part of the urinary apparatus, are double in the normal state, a right and a left ; they are entirely distinct from each other, having no communication in substance, and connected in one system only by means of the bladder. They are situated in the lumbar region, on the two sides of the vertebral column, behind the peritoneum, and are connected with the adjacent parts only by loose cellular tissue. § 2345. They have the form of a bean. Their anterior and posterior faces are smooth. Their, external and internal edges are convex in their upper and lower parts, but in their centres is a considerable depression, termed the fissure of the kidney (hilus renalis). The kidney is divided in this part for about half an inch, into an anterior and a posterior half, between which pass the excretory duct and -the bloodvessels. The blood-vessels are arranged so that the venous trunk is situated before, and followed by that of the artery, behind which the ureter commences. The branches of the renal artery and vein intercross. When the three vessels have arrived at the fissure of the kidney, they divide near the inner edge of the gland into three principal branches, which soon ramify. The blood-vessels then divide into two series, an anterior and a posterior, which receive the vessels of the pelvis. (1) B. Eustachi, De renibus libellus, Venice, 1543. — J. Lœsel, Scrutinium renum, Königsberg-, 1642.— M. Malpighi, De renibus, in ex. de viscerum structura. — L. Bellini, De structura renum, Florence, 1662.— Bertin, Mémoire pour servir a l’ histoire des reins, in the Mémoires de Paris, 1745, p. 108. — A. Ferrein, Sur la structure des viscères nommés glanduleux, et particuliérement sur celle des reins et du foie ; in the Mém. de Paris, 1749, p. 709.— J. F. Droysçn, De renibus et capsulis renalibus, Gottingen, 1752. — A. Schumlanski, De structura renum , Strasburg, 1788. — C..G. Eysenhardt, De structura renum observaliones microscopicce, Berlin, 1818. — A. H. C. Westrumb, Comment, phys. de phœnomenis quæ ad vins sic dictas lotii clandestinas demonstrandas referentur, Gottingen, 1819.— Mappes, Quelques considérations sur la structure du rein et du foie ; in the Journ. compl. des sc. méd. vol. xii. p. 223. § 2346. The proportional size of the kidneys varies. Generally these organs are larger the .nearer the fetus is to its period of formation : they however present, even under this point of view, individual differences, which are independent of the age, and which seem to relate to the size and energy of the other excretory organs. Generally speaking, the two kidneys are equal in size : both, however, frequently vary extremely, although the side of the body has no effect upon it. The ancients asserted that the right kidney is always larger than the left, which is incorrect. E. STRUCTURE. § 2348. They are surrounded by a very loose cellular tissue, most generally abundantly provided with fat, and termed the adipose membrane., or capsule of the kidney (mem. s. capsula renum adiposa ). We find below this cellular mass a whitish membrane, reddish on its two faces, the texture of which is not evidently fibrous, but which is very solid, and resembles the fibrous membranes. This capsule envelops the entire kidney ; it only presents an opening corresponding to the fissure, for the passage of the blood-vessels and the excretory duct, and it adheres intimately in its whole extent to the substance organ, § 2349. The kidneys are formed of two substances, which differ much in color, situation, consistence, and texture. They are the cortical or glandular substance ( substantia corticalis , s. glandtdosa ), and the medullary , tubular , or fibrous substance ( s . medullaris , tubulosa, s. fibrosa). face of the kidney, but extends also to its inner face by several arched prolongations, between which the medullary substance is situated. It consequently forms a collection of cavities, united by a common base, the culs-de-sac of which are turned outwaid. Thus the cortical substance forms the external and colored part of the kidney ; it is about two or three lines thick : its color is redder than that of the medullary substance, and it is much less consistent. in it. § 2351. The medullary substance is inclosed in the preceding, and is composed of a mass of rounded, conical, or pyramidal bodies ( pyramides malpighianœ ), the bases of which are turned outward, and the blunt summits inward ; if we except the most internal part, which is only some lines high and broad, and which constitutes the renal papilla {papilla renales ), it is entirely enveloped by medullary substance. It opens in this place into the commencement of the ureter or pelvis. The summit of the renal papillæ usually, but not always, presents a greater or less number of rounded openings, which although small, are visible to the naked eye. The papillæ, which have a depression, present openings only in this groove, while in those which terminate simply in a point, the foramina are arranged around the summit. which is continuous with the inner membrane of the pelvis. The number of these papillæ varies from seven to twenty. They are distributed in three series, a middle, an anterior, and a posterior, all of which are directed from above downward. Those of the inner series are turned inward towards the median line of the body : those of the anterior go backward, and those of the posterior forward, that is in a direction opposite to the preceding. The superior go downward in every direction. § 2552. From this description it follows that the kidneys are composed of about fifteen segments, termed lobules (lobuli renales , s. renculi ), each of which is formed in turn of medullary and of cortical substance, and the cortical envelops of which are continuous with each other. § 2354. The surface of the cortical substance is not smooth, but seems formed by numerous irregular, rounded, quadrangular, pentagonal, or hexagonal spaces, arranged very compactly, which are not half a line in diameter. These spaces are confined by small vessels, which send branches within them : they consequently have a brighter color than that of their edges, which are formed by these vessels. We also find in every part in the cortical substance, rounded corpuscles, appearing to the naked eye as very small points. These corpuscles depend on the most minute ramifications of the blood-vessels, particularly the arteries, andin connection with them they have the form of a bunch of grapes. • Some anatomists, especially Malpighi, Bertin, and Schumlansky, consider them as special organs, different from the branches of the vessels, as glands or bursts, on the parietes of which the vessels are distributed. Farther, authors are not agreed in respect to them, for Bertin has described and figured -them much larger than those admitted by Malpighi, while the observations of Schumlansky, from which those pf Eysenhardt do not essentially differ, agree with the assertions of Malpighi. Others, as Ruysch, consider these corpuscles not as glands, but. as branches of vessels. It is more probable that they are formed by the twigs of the arteries, and by the roots of the excretory passages in the cortical substances, united, by a mucous tissue, and that they are not hollow. In this manner the two opinions may be reconciled. though the transition of them to the arteries is easity perceived. § 2355. Besides these glandular corpuscles, the vascular ramifications to which we shall return hereafter, and finally the soft and whitish tissue which unites all these parts, and to which Ferrein particularly has called the attention of anatomists, the cortical substance also includes numerous small, white, and very tortuous canals, called the cortical canals , or ducts of Ferrein ( C . corticales). These passages frequently anastomose together, usually proceed separately, sometimes unite in pairs, and circumscribe small and infinitely varied spaces. They compose most of the cortical substance, and are very probably the excretory canals of the corpuscles above mentioned. These canals are tortuous in the cortical substance, but become straight in the medullary substance.' When looked at attentively we observe here and there that the change in direction regularly commences rather high, some distance from the surface of the kidney, so that the cylindrical prolongations of the medullary and the cortical substance reciprocally penetrate in numerous points. substance in the form of angles acute at the base, into several trunks, which generally are not much larger than they, and proceed side by side toward the summit of the papillæ ; but according to some anatomists, particularly Ferrein and Eysenhardt, they do not extend to the openings in these papillæ, but terminate before arriving there. The same writers add that the openings of the papillæ only lead into small culs-de-sac about one or two lines deep, which like them are much broader than the canals of which we speak , and also fewer, there being according to Ferrein, twenty in each papilla. We have sometimes seen very distinctly some canals which extended entirely through the renal papillæ, so that we admit a direct continuity between the urinary passages and the openings of the papillary eminences. We are more disposed to adopt this opinion, as it is very easy to inflate the passages through the papillæ, since in large animals even an injection passes from the artery into the whole papilla, and urine is pressed out from it in compressing the cortical substance. § 2356. Each lobule of the kidneys then is composed of several masses of canals, which are at first tortuous, then straight, arranged very compactly, which have their base turned upward, their summit downward, but represent the form of the whole, and are only more elongated. The right part of these canals, which is contained in the medullary substance, has long been known, for it is mentioned by Berenger de Carpi ; but it is described most correctly by Bellini : hence they are termed the ducts of Bellini ( ductus , s. tubuli Belliuiani , s. renales). Until the time of Ferrein these canals, which are visible to the naked eye, were thought to be simple : but it follows from the researches of this anatomist and those of Schumlansky, that each is a fasciculus of several hundred passages, termed the pyramid of Ferrein. Each tortuous canal is about one sixtieth of a line in diameter. The total length of all these passages collectively is, according to Ferrein’s estimate, more than sixty thousand feet. There are in each lobule seven hundred pyramids, and hence as each kidney is composed of fifteen lobules, there are about ten thousand pyramids. G. VESSELS. § 2357. The two series of vessels, after being arranged in the fissure of the kidney in the manner mentioned above, enter into the substance of the organ on a level with the base of the renal papillæ, and substance. Their branches describe arches turned towards one another, which principally surround the bases of the pyramids of Ferrein or the different segments of the inner substance. Between these arches the anastomoses are but few and small. Although they follow the divisions of the medullary substance they are not distributed within it, but almost exclusively in the cortical substance, first in the segments between the papillæ, then in the outer layer of the kidney. Numerous small branches radiate from the convexity of the largest ; these surround the base of each lobule, and ramify more and more to give rise finally to glandular corpuscles. Many of these branches penetrate to the external face of the kidney : others do not extend so far. The arteries and the veins reciprocally attend each other. Still, although the direct communication between these two orders of vessels, is admitted and is easily observed, we are as yet unable to discover any between the most minute twigs of the veins and the glandular corpuscles, while these latter adhere very intimately to the ramifications of the arteries, with which they represent, as we have already mentioned, a bunch of grapes. § 2358. The nerves of the kidney are proportionally very small ; they arise from the renal plexus of the great sympathetic nerve, are situated on the surface of the arteries, but do not penetrate deeply into the organ. II. URETER. § 2359. The ureter(l) commences at the fissure of the kidney by several rounded canals, the calices, which embrace the papillae, and terminate suddenly or rather become thinner rapidly at their bases, and are continuous with their external membrane. The number of calices generally but not always equals that of the papillæ. Sometimes a calix divided only into two compartments by a slight .prominence embraces two papillæ, which are then .near each other, a structure which leads to the union of two of these prolongations in one. is as small as the ureter. The ureter is about two lines broad and a little tortuous ; it is surrounded by a very loose cellular tissue, and descends on the psoas muscle behind the posterior wall of the peritoneum. It crosses the spermatic vessels situated before it and above the primitive iliac artery, to enter into the pelvis : it then approaches that of the opposite side, being about an inch and a half distant from it, and arrives at the lower and posterior part of the bladder. After proceeding three or four lines between the fibres of its muscular tunic, forming a prominence directed from above downward and from without inward, it opens by an orifice which is slightly narrower, having the same direction, but no valve. § 2360. The ureter is formed of two superimposed layers. The external is composed of a compact cellular tissue. It has a fibrous appearance, but no muscular fibres. The internal is a thin and smooth mucous membrane, which is continuous above with that of the renal papillæ, below with that of the bladder. III. BLADDER. § 2361. The bladdçr( 2) ( vesica urinaria ) is an elongated rounded reservoir, the length of which exceeds its breadth and thickness ; it is situated in the cavity of the pelvis, behind the symphysis pubis, on the outside of the peritoneum, before the rectum in the male and the vagina in the female, and is surrounded by a very loose cellular tissue.(3) (2) J. Parsons, Description of the human urinary bladder and the parts belonging to it, London, 1742. — A. P. Walter, Decolto vesicœ virilis , Leipsic, 1745.— J. Lieutaud, Observ. anat. sur la structure de la vessie; in the Mém. de Paris, 1753. — J. Van Beekhoven de Wind, Diss. de ureteribus et vesicà urinaria, Leyden, 1784. (3) As the recto-vesical operation for stone, which becomes more advantageously known every day, requires a very exact knowledge of the anatomical relations of the bladder, we shall quote here the description of it by Sanson. (Des moyens de parvenir à la vessie par le rectum, Paris, 1817, p. 15.) The base of the bladder is extended from behind forward, from the recto-vesical layer of the peritoneum to the origin of the urethra, is continuous on the sides with the lateral regions of the organ, although there is no very distinct line of demarkation between them, and its dimensions are nearly equal in every direction : it is united by firm adhesions to the ureters, the vasa deferentia and the vesiculæ séminales, which passing through it obliquely from behind forward and from without inward, thus divide It into three surfaces, two of which are lateral, convex, broader anteriorly than posteriorly, situated on the outside of the seminal vesicles, and correspond to an abundant and fatty cellular tissue, which separates them from the levatores ani muscles, while the third, the central, exists between the testicles, is triangular, having a base which looks back- We distinguish in the bladder an upper and rounded part, termed the base (fundus), a central part, the body, and an inferior part, the neck ( cervix , s. collum vesicœ urinariœ). these two passages. It is continuous at its lower extremity with the urethra, at the upper with the urachus, a kind of ligament which proceeds towards the umbilicus along the anterior wall of the anterior face of the peritoneum, gradually becoming thinner. peritoneum. This membrane, which adheres to the subjacent muscular tunic by a very loose cellular tissue, is reflected from the bladder on the upper part of the anterior face of the uterus. The rest and largest part of the bladder is covered only by a very loose layer of cellular tissue, which unites it to the adjacent organs. ward, and corresponds to the peritoneum, and a summit turned forward, which looks to the prostate gland and rests directly on the centre of the rectum, and follows its curve exactly to the gland. It is there separated from it, and goes obliquely from behind forward and a little from below upward to the neck of the bladder, where if blends with the origin of the urethra, which may be regarded in some measure as its continuation. 'I his latter, the origin of which is embraced by the prostate gland and blended with the neck of the bladder, is not by any means so near the symphysis pubis as has hitherto been believed, since, placed upon a line which would extend from the lower part of this symphysis to the summit of the coccyx, it is about two inches distant from it, first passes through the prostate gland, approaching the rectum a little, then becoming loose goes directly towards the root of the penis, entering it below the arch of the pubis, from which it is about fifteen lines distant ; at the same time it is about fifteen lines distant from the intestine, with which it forms an angle open towards the perineum. The skin of this region and the prolongation of the sphincter downward, the urethra forward, and the last portion of the rectum provided with this same spliincter posteriorly, form the three sides of a triangular space filled by fatty cellular tissue, the base of which corresponds to the raphe, and at the summit of which is the prostate gland. If, taking the cavity of the rectum for a point of departure, we examine the parts before the intestine in the order in which they appear, following the median line of the body, we find : 1st, on leaving the central portion, and proceeding obliquely from behind forward and from below upward, the anterior wall of this portion, a more or less dense layer of loose cellular tissue containing a net-work of small veins, the lower wall of the bladder and its cavity; 2d, on leaving the curve formed by the intestine below this region to go towards the anus, and following a more horizontal direction : the anterior wall of the rectum, a thin compact layer of cellular tissue, the prostate gland perforated by the part of the urethra where we remark the crest of the urethra and the orifices of the vasa deferentia ; 3d, finally, on leaving the lowest part of the intestine, and following a horizontal line from before backward, the anterior wall of the rectum united to the sphincter, the triangular space mentioned above, and entirely forward, the bulb of the urethra and the posterior part of the bulbo-cayernosus muscle. In following this direction, proceeding from any point whatever, we open no vessels, except the capillary anastomoses which establish the communication between the two sides of he vascular system. F. T. The texture of the muscular membrane is very complex : it may, however, generally be reduced to two superimposed layers, which, however, interlace at intervals. The external layer, the strongest and most compact, is formed of longitudinal fibres ; these fibres ascend from the lower extremity of the anterior and posterior faces of the bladder toward the base of the organ, where they partly anastomose with each other, and partly also go from within outward. The posterior external fibres are reflected from above downward some lines below the urethra, go thence forward and upward, and are then continuous, from without inward, with the anterior longitudinal layer. when the bladder is distended. Below this second layer we find in several parts, but principally downward, some thinner muscular fibres arranged longitudinally, which form in this place a third layer. § 2363. Next to the muscular tunic come the vascular membrane, which is very thin, and the mucous membrane. The latter is apparently smooth, or at least its villosities are very minute. There are generally no muciparous glands visible on its posterior face, except at the neck of the bladder ; these glands, however, may sometimes be seen when morbidly enlarged. § 2364. The internal face of the bladder is smooth in nearly its whole extent, except some inconstant prominences, which are often produced by the internal muscular layer. The posterior face of the neck, however, presents an eminence which leaves the orifice of each ureter, is directed downward and inward, unites below at an obtuse angle with that of the opposite side, on the median line, and thus gives rise to an angle projecting downward, termed the trigonus of the bladder or of Lieutaud. This eminence is formed by some fasciculi of the internal muscular fibres, which are more numerous in this part, the upper extremities of which are attached around the orifices of the ureters, and which in contracting extend and consequently enlarge these orifices, and thus facilitate the flow of urine into the bladder.(l) IV. URACHUS. § 2365. The urachus (1) is an elongated, very thin cord, which is entirely enveloped by the peritoneum ; it gradually becomes thin from below upward, is attached directly to the anterior wall of the abdominal cavity, and goes from the base of the bladder towards the umbilicus, but frequently does not extend as high. Its fibres are more or less distinctly continuous with those of the muscular membrane of the bladder. the contrary, think it is full and solid. The latter writers assert that this cord is composed, beside its peritoneal tunic, of four layers, intimately united at its upper part, that is, in most of its extent ; they separate near the summit of the bladder, and in passing under its muscular membrane, go, two on the sides, the other two on the anterior and posterior faces of the bladder to its neck. They add that these two layers unite with each other and with the peritoneal coat more intimately as age advances. Walter, on the contrary, states the urachus to be formed externally by longitudinal and then by circular fibres, and after that by the vascular and muscular membranes of the bladder. We may introduce into it for some inches a sound and mercury, but it terminates at the side of the umbilicus in a cul-de-sac, and often contains a reddish fluid. From our observations it follows that generally the urachus is completely obliterated when the body is perfectly developed, and often even long before this period, and thus it is then changed into a perfectly homogeneous cord, although we have often seen the arrangement mentioned by Walter. this structure, which Noreen has figured very exactly. (1) J. C. Peyer, Observât, circa urachum, Leyden, 1721. — J. Noreen, De mutatione luminum in vasis hominis nascentis , in specie de uracho, Gottingen, 1749. — P. A. Bœhmer, De uracho in adulto homine aperto , cum cjusd. anat. ovi hum., Halle, 1765. — A. Portal, Sur la structure et sur l'usage de Vouraque dans l'homme ; in the Mém. de Paris, 1769, p. 19. § 2366. The urethra, { 1) the termination of the urinary system, is a canal narrow in proportion to the bladder, which is continuous by its inner extremity, the vesical orifice, with the neck of the bladder, and by its outer extremity, the cutaneous orifice, with the common integuments. It is composed in both sexes of a mucous membrane covered with a loose and spungy cellular tissue, and a very complex vascular net-work. It is much shorter in the female than in the male, being about two inches long in the former and eight in the latter. The urethra in the female, on the contrary, is much broader than in the male. In both sexes this canal is situated below the organs of pleasure, that is, in the female below the clitoris, and in the male below the corpus cavernosum of the penis, which latter it contributes to form. From the different length of these parts it does not open at the same place in the two sexes. In fact in females its external orifice is situated directly before the entrance of the vagina, and between the external labia ; in males at the anterior extremity of the penis. As in the male it is also the excretory canal of the semen, it will be more convenient to describe its texture when treating of the genital organs. transparence, slight viscosity, and particularly its peculiar odor. The urine is composed of numerous constituent parts, which vary more in their proportions than number and nature, at different periods, than in any other animal liquid. nerally dissolved in the water, are : 1st. Urea, which of all the animal substances possesses the most azote, as it contains thirty-two per cent, according to Fourcroy and Vauquelin ; forty-three per cent, according to Berard ; and even forty- (1) A. Moreschi, Commentarium de urethrce corporis glandisque structura , Milan, 1817.— Amussat, Remarques sur l’urèthre de l'homme et de la femme ; in the Archiv, gên. de méd., vol. iv., p. 31 and 547. — E. Home, Mém. sur la structure de l’urèthre, d’après les observations microscopiques ; same journal, vol. ii., p. 140. — T. Ducamp, Traité des rétentions d’urine, Paris, 1822, p. 1. 4th. Several salts, viz. the lactate of ammonia, sulphate of potash, sulphate of soda, phosphate of soda, hydrochlorate of ammonia, and the earthy phosphates, with some fluate of lime. Besides these substances, which enter regularly into the urine, we sometimes recognize by our senses several constituent principles of the body introduced into the system in different modes. Thus, for instance, rhubarb colors it a deep yellow, and asparagus communicates to it a disagreeble odor. Although these substances also occur in greater or less quantity in the other excretory fluids, especially in those exhaled by the lungs and the skin, and in the matters expelled directly from the intestinal canal, they nevertheless occur more frequently in the urine, so that the urinary system seems to be the principal excretory organ of those materials which cannot be assimilated. It necessarily exercises a peculiar attraction for these substances, in order to remove them from the blood and fulfil its function. state : thus the urine is more or less modified in all diseases generally. § 2368. But the urine constantly presents differences also in regard to the greater or less length of time which has elapsed between its emission and taking food or drink. Upon this is founded the distinction between the urine of ihe drink, and the urine of digestion or of the blood. But it must be admitted that these differences are very slight. The urine of the drink, which is voided directly after a meal, is very watery and limpid. The urine of digestion, voided some hours after eating, during the digestive process, is more colored, less watery, more odorous, and usually presents the smell and taste of some of the articles of food. Finally, that which is passed when digestion is finished, the proper and perfect urine, is more highly colored, and less in quantity : it has not the characters of the ingesta, but on the contrary, presents the characteristic smell and taste of the urine. From comparative experiments, the urine of the food contains only one thirteenth of urea, one sixteenth of uric acid, and one fourth of the salts found in the urine of digestion or of the blood. carried to the urinary system only by the vascular system, or whether they do not proceed there directly by a shorter route, and consequently, whether there are not secret urinary passages ( vice urinaria clandestina). 1st. The rapidity with which fluids, especially cold water, are expelled with the urine, and particularly the great quantity of fluids evacuated in a short time through this passage, whether these liquids have been introduced into the intestinal canal, or injected into the cavity of the abdomen. instances of which we mentioned above. 3d. The presence in the urine or in the lymphatic vessels between the mesentery and the urinary system, of these substances, or of other materials formed even in the body, as the saccharine matter in diabetes, although the blood contains no trace of them. 4th. The presence of urine in the bladder, although the kidneys have been destroyed, the ureters tied, and even when the kidneys did not exist, or at least they did not communicate with the ureters. The manner in which the substances contained in the urine can arrive at the urinary system without passing through the vessels, has been explained in several different ways. 1st. Some think there are no visible channels, but that the phenomena depend simply on transudation through the adjacent parts, particularly from the intestinal canal into the bladder, through the medium of the mucous tissue. (2) 2d. Others admit a retrograde motion in the lymphatic vessels and urinary system, and even support their opinion by those cases where the valves of these vessels have an opposite direction, and are turned from the heart. (1) C. G. Kratzenstein, Theoria ßuxus diabetici ejusque sanandi methodus , Halle, 1746. — Darwin, Zoonomie, vol. i. — -Wollaston, in the Phil, trans. 1811. — Treviranus, Biologie , vol. iv. p. 513-521. — Morichini, in the Mem. della soc. Hal., vol. xvii.-Tiedemann and Grnelin, Recherches sur la route que prennent diverses substances pour passer de l'estomac el du, canal intestinal dans le sang, sur la fonction de la rate et sur les voies cachées de l'urine , Paris, 1821. (3) P. J. Hartmenn, Super urinæ diâpedes quœstiones, Utrecht, 1776. — G. G. Erhardt, De secrelione lotiiunica et svfjicientc, Erfort, 1799. — J. Jacopi, Esame della doclrina di Darwin sulmoio rclrogrado dciliquidincivasi Zûi/att'd, Pavia, 1804. Nothing can be concluded from the last two arguments, for the sympathy between the stomach and the urinary system does not depend on mechanical connections between them, and solid bodies penetrate through unusual channels formed by these bodies from the compression they exercise. In order to refute the fourth argument, it is sufficient to remark that we do not in fact find urine in the bladder when the kidneys have been entirely destroyed, that a portion of the kidney still remains where they seem to have been entirely destroyed, that no urine collects in the bladder after tying the ureters, if the bladder be entirely emptied ; and finally, that the cases of a noncommunication between the ureters and the kidneys are very doubtful. To the third argument we may answer, that at least all the immediate principles of the animal substances do not exist in the blood ; those found there do not exactly resemble those in the body, since the same substances occur in other parts of the body, from whence it is not proved that they pass into the urinary system : that very possibly the substances proved to exist in the urine, might have disappeared from the blood or were concealed in some mode : that these substances have not been looked for in the arterial, but in the venous blood : finally, that according to Magendie, we may prove the existence of one of these substances, the hydrocyanate of potass, in the urine, in any quantity however small, while after mixing it with the blood, even out of the body, we cannot detect it, even when in great quantity, by chemical reagents. Treviranus asserts(2) that this phenomenon proves nothing, as the serum of the blood contained less rhubarb than the urine. But it is easy to refute this objection, as the rhubarb is distributed through the whole mass of the serum, and could only be removed from it by the urinary system. The lymphatic vessels, situated near the mesentery, may either have sent these substances into the urinary system, and have accidentally imparted to them a retrograde motion, contrary to that which the fluids generally follow, although we have no right to conclude that foreign substances always enter the urinary system through this channel, nor even by admitting the retrogade motion, that they were introduced by it. The facts alledged in support of the second argument, do not contribute in manner to the explanation given of them. The formation and the want of decomposition in certain substances would not be explained more easily by this theory : for even admitting this channel, which is not much shorter, they are no less subject to the organic action : but Davy’s observations prove, that under the influence of electricity, bodies may be separated contrary to the laws of chemical affinity, and earned far by the fluids, without combining with other substances which these fluids contain, and which have great affinity for them. Finally, in regard to the first argument, the rapidity with which drinks and certain substances pass into the urinary system, is not in fact as great as has been asserted, and may be easily explained by the short distance they proceed, even admitting that they are carried there by the blood. If we find rhubarb in the urine in seventeen minutes, if it disappears from this liquid at the end of some hours, if it colors the excrement after six or seven hours, and is then found again in the urine, this fact does not prove as Treviranus asserts/ 1) that the rhubarb first found, has arrived at the urinary system by a shorter route than that afterward observed. The rhubarb which appears first in the urine, has undoubtedly passed from the stomach, to the inner and absorbing face of which it was presented, without being decomposed into the sanguineous system, and seventeen minutes is not too. short for the latter to come to the urinary system. The action of the rhubarb on the inner face of the stomach and intestinal canal, gradually causes the mucous membrane of these organs to a greater secretion, which surrounds them on every part and diminishes absorption. When this excessive action abates, the rhubarb is again absorbed. But there is another cause to which we must probably attribute the disappearance of the rhubarb in the urine during a certain length of time, viz. that the action of the kidneys is l.ess energetic, while that of the alimentary canal is increased. 1st. The opinion that the cellular tissue serves as a conductor, is very improbable, first, because the application of phenomena observed in the inferior animals, to the theory of those which occur in the superior animals, leads only to uncertain results, since by admitting this supposition, it is difficult to explain why the passage takes place through the kidneys. 2d. The retrograde motion in the lymphatic vessels is very improbable, at least in the normal state, on account of the existence of valves. The cases where it is asserted the valves were found arranged contrary to what they are generally, are only exceptions, or at least are not sufficiently proved. Farther, this arrangement could not be general, since then there could be no absorption from the bladder. It is not proved that these valves are arranged in one manner in certain lymphatics, and an opposite manner in others. 4th. Finally, another circumstance prevents its admission, viz., that we have never found between the digestive canal and the urinary passages, any substance in these two systems not contanied in the sanguineous system, and even when this phenomenon occurs, it can always be explained by saying that the substances in this place, especially in the lymphatic vessels, have come there from the urinary system. I. KIDNEYS. § 2374. 1st. The kidneys are much larger proportionally the younger the fetus is : in the full-grown fetus their weight is to that of the whole body as 1 : 80, while the proportion in the adult is as 1 : 240. 2d. In respect to form they are more elongated, and the pelvis is nearer the anterior face, so that the renal fissure is less developed. Their surface is not smooth ; they do not form a coherent and homogeneous mass, but are composed of several lobules, which are at first distinct, but are united so as to produce the larger lobes, which are very evident in the adult, where, however, they are not separated. The medullary substance is more abundant in proportion to the cortical substance, than in the adult, at least in the full grown fetus. The fasciculi of the urinary passages, or the pyramids of Ferrein, are separated from one another more easily, and like all parts of the body, are evidently composed of globules, which are not seen in the adult ; on the contrary, the passages are more difficult to be distinguished. Here then, also, as in the muscles and the lungs, the large parts are formed before the small. § 2376. From the narrowness of the pelvis, the bladder is not contained in this cavity ; it is then situated much higher than in the adult, so that the urethra is proportionally very much longer. pears. It is at first hollow, and according to our observations, it retains this character in the full-grown fetus. At this period we can distinguish in it all the constituent membranes of the bladder with which its cavity communicates. This cavity is at first much larger proportionally, the younger the fetus is. In the full-grown fetus, and still more at the periods preceding birth, we can follow the urachus a greater or less distance, but always several inches beyond the opening of the umbilicus, sometimes even the whole extent of the cord. Analogjr with animals, and several observations upon man, authorize us to think that it passes at first entirely through the umbilical cord, and dilates between the envelops of the fetus, to give origin to a membranous vesicle, the allantosi , to which we shall return when describing the human ovum. This cord is certainly hollow, for even in the full-grown fetus we have injected it with mercury through the bladder, and the injection extended more or less in the umbilical cord. Our observations on this subject agree with those of Rcederer(l) and Noreen.(2) Several of the ancient anatomists, and even Trew, among the moderns,(3) have admitted that the urachus is full and solid in the fetus, as it normally is in the adult. This erroneous opinion depends upon a great inflexion in the canal near its lower extremity ; hence, when the bladder is distended, the muscular fibres are so adapted to its sides, that the opening by which they communicate is closed. § 2378. The urinary system is one of those anomalies which occur most frequently,(l) particularly as respects those of formation, for the most striking differences it presents, relate to the form, situation, and size of its different component parts, and also to its vessels. Besides, its cavity not unfrequently includes foreign bodies, which depend particularly on alterations in the chemical composition of the urine. and quality. The differences in respect to quality principally affect their situation. Sometimes there is no trace indicating that a kidney has ever existed in the place where it is not found ; the single kidney occupies the usual place, follows the normal direction, and we discover that it is formed by the union of the two, not only because it is larger than in the normal state, but also because it is contracted at its centre, from the excess in the number of its vessels, its fissure, pelvis, and ureter. Sometimes the two halves of the single kidney are situated each in the usual place. only at their lower part and to a greater or less extent, so that they (1) Baillie, Engravings, London, 812, fasc. vi-viii. — C. Bell, Engravings from specimens of morbid parts, preserved in the authors collection selected from the division inscribed urethra , vesica, renés , morbosa et lœsa, &c. London, 1813. — J. Howship, Practical observations on the diseases of the urinary organs , particularly those of the bladder , prostate, gland, and urethra, London, 1816. form a semicircular mass, which is concave upward and convex downward. The union extends more rarely to their whole height, in which case they are changed into a rounded or square mass. 6th. They are more oblong than usual. 7th. The situation of the pelvis on the anterior face. These two anomalies generally attend enlargement, but they sometimes occur also although there is no mark of hypertrophy. the pelvis. § 2380. Several of these anomalies are developed also during life only, as is true of abnormal enlargement and diminution. Not unfrequently, in fact, the kidneys enlarge sometimes to an enormous extent, although they change their texture, or on the contrary they disappear and are almost entirely effaced. In the latter case sometimes they diminish much in volume, but their mass continues solid, or they even preserve their size or enlarge, but their substance is almost wholly destroyed, and they are changed into a sac with thin parietes. Wasting of the first kind supervenes after a disease of the organ ; but not so with the second, which often depends on an obstacle to the escape of the urine which exists below îhe kidneys. The most common consecutive- deviation of formation is their abnormal dilatation or distension from an obstacle to the course of the urine situated in the ureter, or in another portion of the urinary system, or even out of it. Obstacles of the first kind are calculi and contractions ; those of the second are the engorgement of the glands of the pelvis, the swelling of the internal genital organs, the adhesions of these parts either with each other or with the adjacent organs, &c. principal characters are : At the lower extremity of the anterior face of the abdomen, above the symphysis pubis, is a reddish, soft, rounded place, the edges of which are continuous with the common integuments, and at the base of which are two mammillary eminences directed one towards the other, whence urine continually dribbles. It is the bladder in the form not of a pouch but a layer, the anterior face of which is formed by its mucous membrane. Behind this membrane is the muscular tunic, covered at its upper part by the peritoneum. The eminences are the orifices of the ureters situated in the usual place, and which are not generally abnormal, except from their great breadth. bladder, and consequently much lower than usual. The urethra then most generally opens above the penis in the male, and the clitoris in the female : it is more or less cleft, and more or less imperfectly developed. Considered generally, the external genital organs seem to have separated from each other to the right and left. tive or accidental. 1st. Excessive size. Here there is sometimes simple dilatation, and sometimes an increase in mass and volume. This anomaly generally depends on an obstacle to the course of the urine, situated at the lower part of the bladder or in the urethra. 2d. The considerable development of the muscular tunic, which sometimes occurs without dilatation, or even when the bladder is. unusually small, which depends particularly on the presence of a foreign body, as a calculus, in the bladder. 3d. Hernias of the inner membrane of the bladder through the muscular tunic ( appendices , s. processus),(l) which are very rarely congenital, and commonly arise from the same cause as the preceding. excessive distension. 5th. Displacements , hernias of the bladder. The bladder most generally projects at the base, and gives rise to vaginal hernia when it rests on the vagina, either because it has become very heavy, as in the cases where it is filled by a calculus, or because it is depressed by the contraction of the space it occupies, as in pregnancy. It then causes a more or less perfect inversion of the vagina, after which it is itself precipitated more or less, especially when the inversion is congenital. 6th. When the bladder and vagina fall rapidly, there is sometimes an inversion of the bladder. The urethra is necessarily more or less torn, in order that this accident should supervene. § 2384. The two kidneys do not always possess the same consistence. They are sometimes very flabby in persons affected with diabetes, in which case they frequently receive more blood than usual. They are not unfrequently changed into fat. Frequently also a great number of serous cysts are developed in these glands in old persons ; these generally adhere, are filled with a differently colored and generally a limpid serum, which sometimes entirely destroys their substance. In some cases the kidney seems formed primitively of similar cysts. (3) § 2385. When the bladder enlarges, its membranes are also generally thickened by inflammation, become firmer, adhere more to each other, or are destroyed in parts. in catarrh of the bladder. Irregular, rounded, reddish tumors of various sizes are developed on this membrane, principally at the lower part of the posterior wall of the bladder ; these rest upon a narrower base, and have no determinate texture. These tumors, called funguses of the bladder ( fongus vesicas urinariœ), are observed principally in males, and at an advanced age. § 2386. Of the foreign bodies most frequent in the urinary system, and consequently in the ureters and bladder, entozoaries are rare, and calculous concretions are very frequent. (3) Tenon, Sur la nature des calculs ; in the Mém. de Paris , 1765. — Scheele, Untersuchung des Blasensteins ; in the Schwedische Abhandlungen , vol. xxxvii. — E. Sandifort, De calculo renal. ; in the Obs. anat. pathol., 1777, vol. i., p. 6: De calculis renum et vesicœ , ibid., vol. i v., p. 7 ; De lethali urinœ suppressions ex calculo urethrae inserto, indeque natâ duplici hujus canalis rupturâ ; ibid., vol. iii., p. 3. — F. A. Walter, Anatomisches Museum , th. i., Berlin, 1796. — Wollaston, On gouty and urinary concretions ; in the Phil, trans., 1797. — Pearson, ibid., 1798. — Fourcroy, in the Annales du Museum , vol. i. — Brande, in the Phil, trans., 1808. — Magendie, Recherches sur la gravclle, Paris, 1818. — Prout, An inquiry into the nature and treatment cfbiabetes, calculus , and other affections of the urinary organs, with notes and additions, by S Colhoun, M. D., Philadelphia, 1826. — Marcet, Essai sur les affections calculeuses, Paris, 1823. — F. A. G. Hoffmeister, De cakulis urinariis collectanea quœdàm, Leipsic, 1821. in the second. Of the four parts in which they can be developed, the pelvis, the ureter, the bladder, and the urethra, they occur most frequently in the bladder, and most rarely in the urethra.(l) The portion of the cavity of the urinary system which contains them, particularly of the bladder, is not generally separated from the rest by an abnormal septum. Sometimes, however, the calculi are inclosed in a special sac, which communicates with the common cavity by a narrow opening ; they are then termed encysted calculi. This state is doubtless in most cases the source of the calculi existing in the parietes of the bladder. We must admit that the communication at first existing is finally obliterated ; it is impossible to suppose that the concretions were formed except within the cavity of the bladder. b. Most generally, and even most always, the urinary calculi are entirely loose ; but sometimes they are attached to the inner face of the bladder by mucus or thickened and coagulated fibrine, which exists between their prominences. (2) 2d. Texture. The urinary calculi are generally formed of superimposed layers, more or less distinct and more or less concentric. Their centre also is usually formed by a nucleus, which most generally consists of a small mass of uric acid, more rarely of a foreign body accidentally introduced into the urinary apparatus, particularly the bladder. The different layers are generally, but not always, similar in their chemical composition. They are always formed of at least two substances, one solid, the other softer and originally fluid, which unites and connects the particles of the preceding. 3d. Form. The urinary calculi are more or less oblong and rounded, and generally smooth and a little flattened. This character depends in great part on the influence of the organ which contains them, the bladder being round. The form of the renal calculi demonstrates particularly the great influence of the form of the organ on that of these concretions. 4th. Volume. The size of the calculi varies from that of an almost invisible grain to a diameter of several inches ; they are sometimes so large that they completely fill the bladder, and even distend it. always, the same. 6th. J\lode of development. We may mention, as a general rule, that the formation of the calculi depends either on the abnormal state of the urinary system, or on the presence of a foreign body accidentally introduced into the bladder. The abnormal state of the urinary system may vary in several different modes. The secretory portion is generally affected, so that an alteration in the chemical composition of the urine is most generally the cause of the formation of calculi. This accidental production depends more rarely on an abnormal arrangement in the bladder, or the excretory portion of the urinary system. It may, however, be caused by a mechanical obstacle to the emission of the urine, especially by sacs in the parietes of the bladder, by the hernia of the bladder, or by strictures of the urethra. Calculi have even been developed between the glans and the prepuce.(l) 7th. Influence on the urinary system. This influence varies. Whenever they are developed, the urinary calculi, being foreign bodies, cause more or less acute pains, the intensity and nature of which depend on their form, situation, number, and size, independent of the degree of sensibility of the patient. The changes caused by them in the form of the urinary system are, the distension of the membranous parts, particularly the ureters, the thickening of the muscular portion, consequently of the bladder, which often attends their enlargement, but still more frequently the contraction of its cavity, finally rupture, which is more rare, and which occurs particularly in the urethra. cipally and almost exclusively to their chemical composition. Chemical analysis has discovered in them at this date uric acid, the phosphate of lime, the ammoniaco-magnesian phosphate, the oxalate of lime, and the cystic oxyd. There have been found also, but more rarely, less constantly, and in less quantity, silex, carbonate of lime, iron, and two other peculiar substances, the xanthic oxyd, and a fibrinous substance. Wollaston and Brande doubt the presence of urate of ammonia, admitted by Fourcroy and Vauquelin, and consider this salt as produced by the chemical analysis ; but we cannot conclude positively from the arguments with which their opinion is supported that it never occurs in common calculi. Sometimes these substances are distinct, and sometimes they combine in a greater or less number to form a concretion, whence numerous kinds of calculi are formed. sometimes they are smooth, and seem to form always in the kidneys. 4th. Those of the cystic oxyd, more property the renal oxyd, because this substance is very probably developed in the kidneys. These calculi are yellowish and semitransparent. They have no lamellar texture. many separate layers are : 1st. Those of the ammoniaco-magnesian phosphate, or the fusible calculi (calculus fusibilis) of Wollaston and Marcet, the most common next to those of the uric acid. They are white, and more friable than those of the other species. The ammoniaco-magnesian phosphate often predominates, although it. seldom or never forms it alone. The calculi formed around the foreign bodies introduced into the bladder, those developed in ischuria, or between the prepuce and the glans, are most generally of this nature, because in this case the urine is more or less decomposed. and their hardness. Finally, among the compound calculi, there are some in which the different layers are formed bjr as many distinct substances. The number of these substances varies from two to four : but there are generally but two, the uric acid, with a phosphate or oxalate of lime, with sometimes another phosphate, or with silex. In a calculus formed by four layers, Marcet has found, from the centre to the circumference, cystic oxyd, phosphate of lime, oxalate of lime, and the ammoniacomagnesian-phosphate. § 2391. The renal capsules ( renes succenluriati , capsula , s. glandula suprarenales , s. atrabiliares),( 1) are triangular bodies, very flat from before backward, resting directly on the kidneys, to which they are united by a short cellular tissue. They occupy their upper extremity and the upper part of their internal edge. Like them, they are situated on the outside of the peritoneum. B. FORM AND VOLUME. § 2392. We have mentioned the general form of the renal capsules. They are more long than broad, that is, they extend farther from above downward than from right to left. They are only about one line thick. Their form differs on the two sides : that of the left side is a little higher and narrower than that of the right : the left is from fifteen to seventeen lines long, and about three broad : the right is generally from fourteen to fifteen lines long, and twelve or fourteen broad. We remark on their external face the fissures through which the blood-vessels enter and depart. The left capsule usually presents forward a longitudinal fissure, while there are two on the right side, an anterior and a posterior. lowish brown externally, and a deep reddish brown internally. (1) A. M. Valsalva, Diss. anat., III. — B. Morgagni, Epist. anat. XX. — Duvernoy, Comm. Petrop., vol. ii. — Bœckler, De thyroid 'œ, ihymi et glandularum suprarenaliumfunctionibus, Strasburg, 1753. -—J. C. Mayer, De glandulis suprarenalibus, Frankfort, 1784. — Riegels, De usu glandularum superrenaliumnecnon de origine adipis , Copenhagen, 1790. — F. F. Leonhardi, Diss. de glandulis suprarenalibus , Dresden, 1810. — J. F. Meckel, Abhandlungen , p. 1-277. § 2395. They are composed of two substances, one external, more consistent and yellowish, the other interna], softer and of a deeper brownish red. The first is evidently formed of perpendicular fibres, which are directed from without inward. These two substances are often intermixed, whence the capsule appears spotted externally. The external is divided more or less easily into rounded lobes, which may themselves be divided into lobules, and it is covered by a very thin serous membrane, which intimately adheres to its surface. According to several anatomists, the renal capsules contain a more or less complex cavity. However, after much research, wre are obliged to adopt the opposite opinion ;(1) we think that there is normally no cavity, that it does not form till after death, and that it results either from the spontaneous decomposition of the inner substance, which is not very consistent, or fiom this substance being destroyed by handling it. The substance of the renal capsules, particularly the internal, is very intimately and directly connected with the veins, for the liquids and air injected into these vessels easily penetrate them, and the air often forms in them a cavity, they are so soft. § 2396. The renal capsules are imperfect glands, as they have no excretory ducts. In fact, these ducts have been admitted by some anatomists of note, as Bartholini,(2) Peyer,(3) Valsalva, (4) Ranby,(5) Kulmus,(6) Heuermann, (7) and Bendt.(8) The capsules communicate with the testicles, according to Bartholini, Peyer, Valsalva, and Ranby : with the thoracic canal according to Kulmus, with the pelves of the kidneys according to Heuermann and Bendt. But very careful and numerous dissections have led us to the contrary opinion. The absence of an excretory duct in these organs seems more probable, as it accords with the researches of Morgagni. II. DIFFERENCES PECULIAR TO THE RACES. § 2397. Some writers have asserted that the renal capsules were larger in negroes than in the Caucasian race, and that their medullary substance was darker. (9) We have seen nothing of this in dissecting fetus of two months. Their proportional size gradually diminishes on their first appearance, and the same is true, at least frequently, of their absolute size after birth. They become thinner and dryer, wrinkle, and even entirely disappear in oldage.(l) At the end of the third month they are a little larger and heavier than the kidneys : at four months they are equal in size to these glands, but they are lighter, because their tissue is looser. At the commencement of the sixth month they are only half as large as the kidneys, but their weight is to that of these latter as 2 : 5, since each capsule weighs ten grains, and each kidney twenty-five. In the full-grown fetus the proportion is about as 1 : 3, each capsule usually weighs a little more than four scruples, and each kidney more than half an ounce. In the adult, on the contrary, the relation is as 1 : 23, for the capsule weighs one drachm, and the kidney three and a half ounces. These organs are composed of lobes, which are at first more numerous and more distinct than in the adult ; but they do not always contain a cavity in the early periods of life. suies, although their great size before birth indicates their importance. We have every reason to think, that like the liver, the spleen, the thyroid, and the thymus glands, they contribute directly to the perfect formation of the blood. Their great size in the fetus, their free communication with the venous system, and their nearness to the ascending vena-cava, are at least so many circumstances in favor of this conjecture. Those observers who admit, an excretory duct to the genital organs, necessarily connect the renal capsules directly with them. Other facts, particularly their simultaneous, considerable development in several orders of the mammalia had suggested the same idea to us, (2) before we knew that it belonged to another, but we could not describe the mode in which the renal capsules and the genital organs co-operated. We may also mention in support of this hypothesis, the coincidence of anomalies in the renal capsules with those in the genital organs. Thus, Vauquelin has found the capsules ossified in a cat, from which the ovaries had been extirpated. (3) Lobstein has found that of the left side tripled in size by a chalky mass in a man who had long been affected with syphilis.(l) We have found these organs unusually large in two individuals much addicted to venery,(2) and deformed in a female shortly after parturition, in whom the uterus and one of the ovaries also presented a similar formation. (3) Otto has seen them twice the usual size, in one case where the genital organs were very much developed. (4) The great simultaneous development of these two orders of organs in the fetus, the coincidence of their smallness, and even the simultaneousness of their absence with the development of the encephalon, between which and the genital organs there is so striking a connection in an opposite sense, are circumstances in favor of this hypothesis. Another conjecture very similar to this, is to consider the renal capsules as an imperfect rudiment of the genital organs, (5) although it seems to us too doubtful to think, that if they were connected with the kidneys more intimately, an excess of energy, a momentary excitement alone would be necessary for this connection, acting like a real copulation, should cause the renal capsules to produce a new being. It seems to us less probable that the renal capsules have a mechanical’or dynamical relation with the kidneys, because, that when these latter are displaced, the capsules always preserve their normal situation, so that the two organs are then more or less distant. § 2400. The renal capsules are very rarely abnormal, (7) and inasmuch as their anomalies consist in alterations of texture, we may conjecture with great probability, that they depend on the premature extinction of the great power primitively possessed by the organ. A very general primitive anomaly, is their extreme smallness, or their entire deficiency, which attends the imperfect development of the encephalon, and the upper half of the body generally. Only two or three cases of this kind are known, where the renal capsules were found of their usual size. Their imperfect development not only attends alterations of the cerebrum, but the suspended development of this viscus generally, particularly congenital hydrocephalus. cent organ, the spleen. It is difficult to determine whether this state be only a simple division, or whether we should consider it as a real increase in the substance of the renal capsules. Considered in the last point of view, it would gradually lead to the hypertrophy of these organs, some cases of which are known. (2) This hypertrophy is rare : we may presume that it generally depends on an alteration of texture, and it seems particularly coincident with anomalies in the genital organs. § 2401. The organs of generation , the genital, parts ( partes , s. organa sexualia, genitalia , s. generation's inserventia),(3 ) principally serve to perpetuate the species, while the existence of the other systems is directly connected only with that of the individual. They however are directly connected with the organism of the individual, as is demonstrated by the consequences of their absence, whether primitive or congenital, or consecutive and accidental, or produced by a determination of the will. The sexual character which is imprinted on the whole organism, is most evident in them. Of all the organs then, these differ the most in the twTo sexes. A superficial examination would lead to the conclusion, that the genital organs in the male are entirely different from those of the female, and that they cannot be compared. But if we compare them in any animal, or even in man, we shall be satisfied that they have originally the same form, that they correspond perfectly in respect to number, their essential peculiarities in structure and function, that they differ only in size and situation, and that consequently, the analogies between them are much greater than the differences, and that they should be regarded as modifications of one and the same primitive type. It is convenient to add the history of the mammæ to that of the genital system, since they contribute but slightly, or not at all, to the organism of the individual, while in their quality of nutritious organs of the infant, they exert a great influence on the preservation of the species. Besides, they do not differ less in the two sexes than the (3) F. Plazzoni, De partibus gcnerationi inservientibus, libri III, Padoue, 1521.— W. Rolfink, Ordo et methodus generationi dicatarum partium per anatome n cognoscendi fabricant, Jena, 1664. — Id., De sexus utriusque partibus genitalibus specimen , Leipsic, 1675.— Van Horne, Prodromus obscrvationum suaruni circa parles génitales in utroque sexu, Leyden, 1668. other organs of generation. It would be better then, instead of employing the expressions sexual parts and genital parts indiscriminately, as is generally done, to confine the latter term to the organs which produce the new being, that is, to the proper genital organs. All these parts differ from most others, as their active state is proportionally very slight, for it generally does not extend much beyond the half of existence, during which it appears only at long intervals, and requires also, in order to be brought into action, very general, and often very great changes, both in the mode of vitality, and in the structure of the organs. trunk, and are situated within and on the surface of the pelvis. Those of the male and female differ principally’' in this respect, that the first are situated more externally’, and are arranged more longitudinally, while the second are placed more internally. Those parts which in the male are situated on the outside of the abdominal cavity, exist in the female within the cavity of the pelvis, and even those which occupy the cavity of the pelvis in the male, are pushed forward so much that they are found directly below the common integuments. Thus, while the external genital organs in the female, those seen without opening the body, are much fewer and smaller than the internal, the opposite is true of the male ; but we shall demonstrate hereafter, that this difference also does not exist during the whole of fife. § 2403. The best mode is to divide the genital organs, in the two sexes, according to the functions of their different constituent parts ; into the proper genital or formative organs ( organa generationis, s. formantia ), and the organs of copulation ( organa copulationis) . The formative organs in the man, are the testicles, with their excretory ducts, the prostate gland, and the glands of Cowper : in the female the ovaries wfith their excretory ducts, the Fallopian tubes, and the uterus. In both sexes the genital organs are situated at the lowest extremity of the trunk, consequently, directly opposite to the encephalon. In both sexes they differ from the .other organs in the symmetrical arrangement, then constituent parts existing in pairs, or in the contrary case, being situated on the median line of the body’, which divides them into two equal parts. a. Form, situation, volume, and weight. § 2407. The ovaries ( ovaria , s. testes muliebres)(2) are situated at the upper part of the cavity of the pelvis, on the sides of the uterus, to which they are attached only by the ligament of the ovary ( l . ovarii ), a portion of the fold of the peritoneum, which attaches the uterus to the pelvis, and is termed the round ligament. They are rounded and oblong. Their anterior and posterior faces are convex. Their upper edge is also convex and loose. The lower is straight or a little concave, presenting a real vascular fissure ( hylus ). They rest by this latter edge on the upper part of the broad ligament. They become thinner towards their internal and external extremities, but particularly toward the former. Their surface is usually smooth in virgins, and generally uneven and lacerated in aged females. When perfectly developed, they are about an inch and a half long, about four or five lines high, and a little less in thickness. They weigh about a drachm and a half § 2408. The ovaries are covered externally by the peritoneum, below which is a very solid and very resisting white fibrous membrane ( tunica albuginea). These two layers are inseparably united. The internal is perforated at the lower edge of the gland by vessels which pass through it, and are distributed in its tissue. (1) R. de Graaf, De mulierum organis generationi inser vient ibus, Leyden, 1672. J. Palfyn, Description anatomique des parties de la femme qui servent à la génération, Leyden, 1708.— D. Santorini, Obs. anat. cap. XI. De mulierum partibus procreationi dalis. — J. G. Gunz, Observationes de utero et naturalibus fceminarum, Leipsic, 1753. In the normal state they are composed of a thin, smooth, and serous membrane, which adheres intimately to the substance of the gland ; they are entirely closed and filled with a clear and limpid fluid. They vary in size, and they seem to be developed successively. The largest are about three lines in diameter, they are more numerous on the edge of the ovary than in the centre. In virgins their number varies from eight to twenty. B. FALLOPIAN 1 UBES. §2410. The Fallopian tubes ( tubas Fallopiance, s. meatus seminarii)( 4) are the excretory ducts of the ovaries. They are situated before and below these organs, then go from without inward toward the upper edge of the uterus, passing through the upper end of the broad ligament ( ala vespertilionum ), to which they are attached. They are very tortuous, especially in their external portion, and gradually enlarge, so that their diameter, which is only half a line on the inside, becomes by degrees three and four lines. They open into the abdomen ( ostium abdominale) by a mouth surrounded with a fimbriated edge, called the morsus diaboli. This opening projects much on the outside of the outer extremity of the ovary. The internal orifice (ostium uterinum) opens in the angle formed by the union of the upper edge of the uterus with its sides. There is no mark of valve or prominence here. Each tube is about five inches long. §2411. The tubes are covered by the peritoneum, which forms their external tunic, and which is continuous with the inner membrane on the edges of the abdominal orifice. Below the peritoneal tunic is the middle membrane, in which we cannot usually observe any fibres, but it is sometimes composed in vigorous females of two muscular layers, which are formed, the external by longitudinal fibres, and the internal by circular fibres. (5) § 2413. It is pyriform, and much more extensive from above downward than from right to left. Its thickness is much less than its breadth. Its upper and largest part, which is termed the body , is triangular. It gradually contracts toward the base. The lateral edges are straight, the upper is very convex. The anterior and posterior faces of the uterus are very convex, the second more so than the first, so that particularly in the early periods of life, we may admit two posterior lateral faces, which unite at an obtuse angle on the median line. The uterus represents a cavity closed at its upper part, always excepting the narrow orifices of the two Fallopian tubes, but open below and continuous in this direction with the vagina. in the perfect state. The middle region of its body, its thickest portion, (1) J. A. Pratis, Libri duo de uteris, Antwerp, 1524.— -L. Bonaccioli, De uteri sections, Strasburg-, 1529. — M. A. Ulmus, Uterus muliebris, Bologna, 1601. — J. Swammerdam, Miraculum naturce de uteri muliebris fabricâ, Leyden, 1672. — C. Drelincourt, De utero, Leyden, 1682. — M. B. Valentini, De novâ matricis anatome, Giessen, 1683. — G. Bartholin, De utero, Leyden, 1684. — A. Nuck, Adenographia curiosaet uteri Jeminei anatome nova, Leyden, 1692. — F. Ruysch, 'J'ractatus de musculo in fundo uteri observato, antea a nemine detecto, Amsterdam, 1726.— A. Vater, De musculo novo uteri, Amsterdam, 1727. — J. J. Huber, Uteri muliebris partiumque ad earn facientium preecipuarum iterata explicatio ; Halleri leones , fase. I. — I. U. Buchwald, De musculo Ruyschii in fundo uteri, Copenhagen, 1741. — J. Weitbrecht, De utero muliebri observationes ; in N. C. Petrop, vol. i. p. 337. — Sue, Recherches sur la matrice ; in the Mém. pres., vol. v. — J. G. Rœderer, leones uteri humani observationibus illustralœ, Gottingen, 1759. — T. Simson, Observations concerning the placenta, the two cavities of the uterus , and Ruysch' s muscle in fundo uteri ; in the Edinb. med. essays, vol. iv. n. 13. — J. G. J. C. Loder, Demusculosà uteri structuré, Jena, 1782. — J. G. Weisse, De structura uteri non musculosa sed celluloso-vasculosa, Wirtemberg, 1784. — G. Azzoguidi, Observationes ad uteri constructionem pertinentes, Leyden, 1788.— O. F. Rosenberger, De viribus partum efficientibus generatim et de utero speciatim, ratione substantive musculosce et vasorum arteriosorum, Halle, 1791. — C. H. — G. C. Titius, De uteri structura ex ejusdem functionibus, Wirtemberg, 1795. — J. F. Lobstein, Fragment d'anatomie physiologique sur l'organisation de la matrice, Paris, 1803. — J. U. G. Joerg, Ueber das Gebarorgan des Menschen und der tSàugthiere im schwängern und nicht schwängern Zustande , Leipsic, 1808. — C. Bell, On the muscularity of the uterus ; in the Med. chir. trans., vol. iv. 1813, p. 335. — J. B. Belloni, Memoria sopra la vera struttura deliutero, Rovigo, 1821. — Mad. Boivin, Mémorial de l'art des accouchemens , Paris, 1824, p 57. softer than the neck. The anterior and posterior parietes gradually grow thin on the outside, and the internal upward, so that their thickness diminishes from four or five lines to one, and thus resembles that of the tubes, which proceed some lines in the substance of the organ, following an oblique direction from above downward, and from without inward. The form of the cavity of the uterus generally corresponds with its external figure, although it is extremely narrow in regard to the thickness of the parietes, whence it follows, that its anterior and posterior faces almost touch. Its mean breadth does not exceed four lines. The three edges of the body are concave outward and convex inward, while externally, only the upper edge of the uterus is convex outward. The cavity of the neck is circumscribed by faces convex outward, while its outer face is concave, as the organ is con traded a little on its centre. The form of the cavity also differs from that of the outer circumference, in this respect, that it extends above on each side into a long horn, which gradually contracts, and at the summit of which the Fallopian tube opens. The cavity is narrowest in the neck, particularly on the limit between the neck and the body, where it contracts very much. It is termed in this place the upper or internal orifice of the uterus ( ostium uteri internum ). Thence, the neck enlarges to about it's centre, and then again, contracts. It terminates below in the upper extremity of the vagina, by two sacs, an anterior and a posterior, the latter of which is usually longer, but the anterior descends a little lower, and between which we usually observe a transverse fissure, more rarely a smaller rounded opening, termed the os tincæ , the external or vaginal orifice of the uterus ( orificium uteri externum , os uterinum). The two sacs are termed the lips (labia) of this orifice. The inner face of the uterus is smooth in the body, but corrugated in the neck, along the anterior and posterior parietes of which is a longitudinal prominence, which gradually diminishes from above downward, the sides of which present oblique bands, which render it very uneven. On the sides between the two prominences we observe also numerous elevations, which intercross like a net-work. The lips of the os tincæ are smooth, at least if we except lacerations, which are always accidental, and occur rather frequently during parturition. b. Volume. § 2415. In virgins the uterus is about two inches long, nearly half of which is formed by the neck. The greatest breadth of the body is sixteen lines, and that of the neck from nine to ten. The lips of the os tincæ are about ten lines broad, and the breadth of the external orifice of the uterus is about six. fissure is very narrow in this direction. In females who have borne children the uterus commonly never returns to its primitive dimensions, and the orifice of the os tincæ also appears a little broader from before backward. c. Weight. § 2416. The well developed uterus of a virgin weighs between seven and eight drachms ; but in a female who has borne children, and in whom the uterus has contracted as much as possible, it often weighs an ounce and a half. § 2417. The uterus is situated between the bladder and rectum. Its upper half is placed in the cavity of the peritoneum, a fold of which is intimately attached to its surface. In the perfect state it. is situated entirely in the small pelvis, and its base rises only to the level of the upper edge of the symphysis pubis. This part is directed forward and upward: the os tincæ, on the contrary, downward and backward, so that the longitudinal diameter of the axis of the organ corresponds nearly to the upper axis of the pelvis, and it cuts the axis of the body backward and downward. § 2418. The uterus is attached to the adjacent parts by several folds of peritoneum,(l) which are continuous with the serous tunic of its body, from whence they arise inward. The largest are the lateral or broad ligaments (/. uteri lateralia, s. lata). They pass from the lateral edges of the uterus, receive the vessels of this organ between their anterior and posterior layers, go transversely outward toward the circumference of the pelvis, divide this cavity into two halves, an anterior and a posterior, the first of which is smaller than the second, and are continuous with the lateral wall of the peritoneum. Beside these vessels, this fold of the peritoneum possesses more or less distinct transverse muscular fibres, which leave the lateral edge of the uterus and gradually terminate on the outside. (2) (1) J. C. Schützer, De Jabricâ et morbis ligamentum uteri , Harderwyck, 1729. — A. Petit, Description anatomique de deux ligamens de la -matrice nouvellement observés-, in the Mêm. de Paris, 1760.— A. Portai, Observ. sur la structure des parties de la génération de la femme ; in the Mém. de Paris, 1770, p. 183. Another fold, which is much smaller, elongated, and rounded, forms on each side the posterior inferior ligament, or the semilunar fold of Douglas (l. uteri inferius posterius, s. plica semilunaris Douglasii), which extends from before backward from the lower part of the posterior face of the uterus to the rectum. A third, which is still smaller, the inferior anterior ligament (l. uteri inferius anterius ), one of which generally exists on each side, extends from behind forward from the lower part of the anterior face of the uterus to the bladder, embraces this latter, and frequently also possesses muscular fibres. Finally we find on each side a very long and rounded ligament, which leaves the upper part of the lateral edge of the uterus, directly below and before .the inner extremity of the Fallopian tube; it is termed the round ligament (/. uteri rotundum , s. teres). This ligament is first situated between the two layers of the broad ligament, passes behind the umbilical artery and before the hypogastric vessels, is directed from below upward and from within outward directly behind the peritoneum, towards the upper and external orifice of the inguinal canal, is reflected in this place on the epigastric artery, then enters the inguinal canal, proceeds from above downward, from without inward, and from behind forward, emerges from the inguinal canal thiough the inguinal ring, and terminates by dividing into several fasciculi in the fat of the mons veneris, and in the upper part of the external labia. It is composed principally of cellular tissue and vessels, but it possesses also some very distinct longitudinal muscular fibres, the upper of which arise from the external layer of the fibres of the uterus, while the lower come from the lower edge of the two internal broad muscles of the abdomen, which are directed from below upward. the ovaries. When the fibres of the broad and round ligaments of one side act more forcibly than those of the opposite side, the uterus is carried transiently or permanently into one half of the pelvis, an arrangement which we have often observed, al’hough it depended on no mechanical cause, and although the parts which serve to retain the uterus were unaltered in their texture. § 2419. At first view the tissue of the uterus seems to be homogeneous ; we however distinguish in it when unimpregnated, several layers superimposed from behind forward, which have a reddish yellow color, and between which are whitish bands. The vessels of the uterus, which are very tortuous and frequently anastomose together, proceed between these layers both on the anterior and near the posterior face. a. Fibres. § 2420. There is perhaps in anatomy no subject on which opinions are more divided than in respect to the fibres of the uterus, or, to state the question more exactly, in regard to the existence of these fibres generally, their nature, and their arrangement. 1st. Several anatomists, particularly Walter, Bcehrner, Blumenbach, Azzoguidi, and Ribke, formally deny their existence, which is admitted, on the contrary, by Vesalius, Piccolomini, Malpighi, Morgagni, Diemerbroek, Verheyen, Vieussens, Ruysch, Vater, Santorini, Buchwald, Weitbrecht, Monro, Noortwyk, Heister, Haller, Sue, Astruc, Levret, Rœderer, Meckel, Hunter, Wrisberg, Loder, Mayer, Simeon, Calza, Lobstein, and Bell. by most authorities. But the anatomists who admit their existence differ ; some consider the fibrous texture of the uterus as constantly existing; while others, who are more numerous, think that these fibres exist only in certain conditions, as in gestation. It is a fact that these fibres are at least very slightly apparent, except in pregnancy. They however do not form only during this state, but whenever the formative power of the uterus is exalted. Lobstein has found them very apparent in a female where the uterus was much distended by a steatomatous tumor, as it is generally in the seventh month of pregnancy. He attributes this phenomenon to the distension caused by the tumor ; but we have observed them more or less evidently in the uterus of females where analogous tumors existed in the uterus and ovaries, so that we think it more correct to admit that they depend on a change of the proper vitality of the uterus. 2d. Most anatomists consider these fibres as muscular. In fact they differ from the red fibres which form the voluntary muscles, as they are less red, flat, and strongly united with each other ; but their muscular nature is proved by their powerful contraction, either during parturition to expel the fetus and the secundines, or afterward, to contract the uterus and almost obliterate its cavity very rapidly. This in fact is the manner in which the fibres of the uterus act, and their substance presents in the different states of this organ the different modifications observed in the muscular system of organic life, that is, when the uterus is unimpregnated, they resemble the fibres of the arteries, and during gestation, those of the other involuntary muscles, except the heart. The uterus of the female contains also a great proportion of fibrine. Finally we may also mention the analogy with the mammalia, where the uterus is evidently muscular at all periods of life, adding however that by a very remarkable arrangement, the fibres in the uterus of the female do not evidently possess this character, except when the formative power of the organ is increased. 3d. The direction of the fibres is not described in the same manner by all anatomists. Most of them, however, agree that they possess at least two directions, a longitudinal and a transverse ; so that in this respect also they resemble the muscles of organic life. They are however more complex, since we find several layers proceeding in different directions, as the layers composed of fibres which have the same direction proceed several times from within outward ; and as finally the different layers frequently interlace together. the fibres are not arranged regularly. Ruysch admits only a single, unmated, and circular muscle, situated at the base of the uterus. Although several anatomists, as Vater, Monro, and Simson agree with him, it is however certain that the arrangement of the fibres of the uterus is not so simple. Farther the description Ruysch has given of this muscle is not perfectly exact. 3d. The external layer is much thicker than the internal. 4th. The muscular substance is much thicker at the upper part of the uterus, particularly in its base, than in the other regions. It does not exist at all, or at least is very thin, in the neck. (2) 5th. Generally speaking the longitudinal fibres are much more numerous than the others. The circular fibres, however, are more developed at the base of the organ, while the longitudinal fibres are larger near the lower orifice. 6th. The external plane is composed of longitudinal fibres, which depart from the centre of the base, are distributed from above downward on the anterior and posterior faces, follow an oblique and even transverse direction, and disappear toward the neck. Some of these fibres are irregular, others are continuous with the round ligaments. 7th. According to some authors, Rosenberger for instance, the external plane is composed only of longitudinal fibres ; there are however below these fibres other transverse fibres which also go to the round ligaments and to the Fallopian tubes. 8th. We also remark in this plane, oblique fibres which have very different directions, and are tortuous ; these interrupt particularly the longitudinal layers, and occur principally at the lower part of the body. verse and longitudinal fibres. 10th. The inner plane, which is the thinnest, is formed of two layers. The external is composed of two circular muscles, each situated round one of the orifices of the tubes ; they blend together on the median line anteriorly and posteriorly, by the inner part of their edge. Very probably one of these circular layers is the muscle of Ruysch, who had considered the lateral wall of the uterus as the upper, and had neglected the opening of the tube. 11th. Below this layer are longitudinal and oblique fibres, which unite on each side anteriorly and posteriorly to form two elongated triangles, the summits of which blend in the orifice of the tube. (1) Mad. Boivin describes the fibres of the uterus differently. She remarks that after macerating the uterus for a few days, wo observe on each face six fibrous fasciculi, three on the right and three on the left of cacti wall, besides one which is vertical, and which forms the median line. This last layer, which extends from the circumference of the base to the base of the body, presents longitudinal fibres. Each of the others seems to arise from the median line : 1st, at the centre of the base are two fasciculi, one on each side, which extend transversely on the edge of the base to the upper angles, where they fold in the form of tubes, which separate and extend to form the tubes ; 2d, below this first layer of the anterior face, two other broader layers, which occupy the upper half of the body, proceed horizontally on each side from the median line, and a little before the angle of the tube, to unite to other layers of fibres, and there form the origin of the round ligament ; 3d, at the lower third of the median line two other layers of fibres are directed obliquely from below upward, separating on the sides : one portion of this fasciculus unites to the band of fibres of the round ligaments, and the other blends and interlaces with the transverse fibres of the posterior regions of the organ. On the posterior wall of the uterus the arrangement of the fibrous layers is nearly the same as in the anterior wall. The middle layer is more prominent than that of the anterior face, and also presents longitudinal fibres. The fibrous layers of the upper region extend across, leaving the median line, to the origin of the tubes and a little below, where they unite to go to the ovaries, of which they form the ligament. Below is another layer, which reascends obliquely and divides rather distant from their point of departure into two portions : one superior and lateral, turns on the side, and goes to unite forward to the round ligaments ; the other terminates in the form of a ring, and goes to the base of the ovary. At the lower extremity of the median line in the external central region of the neck arc two other fasciculi, which are composed of a portion of the fibres of the median line of the neck, separate some lines from each other, are insulated, and arc attached to the lateral edges of the middle region of the 3acrum, and form the posterior ligaments. These different fibrous layers change their direction during pregnancy. In proportion as the body of the uterus elongates and enlarges, the layers of fibres of the upper regions from transverse become oblique, their median extremities rise towards the middle of the base, and their lateral extremities are depressed, in the same proportion, to the lower third of the lateral edges of the organ, so that at the end of gestation the fibrous layers of the upper and lateral regions have a radiated arrange- b. Internal surface. § 2421. The inner surface of the uterus is covered by a reddish mucous membrane, which is almost smooth, and presents only some very small villosities, which are continuous above and on each side with those of the tubes, and below with that of the vagina. In the recent state this membrane adheres so intimately to the subjacent fibrous substance that it is inseparable, although its structure intimates distinctly that it belongs to the class of mucous membranes ; but after macerating the uterus we can detach some folds of it by care and precaution. We find some muciparous glands only in the neck, particularly at its lower part. Not unfrequently their orifice is obliterated, perhaps from inflammation. They then form more or less numerous large cysts filled with a limpid liquid, produced by the accumulation of their habitual secretion. the ovula of Graaf. iment, and may be compared to a head with Ions' hair, separated in all the extent of the median line of the skull, smooth on each side of the forehead, and situated very near and before each ear : this union in a single fasciculus of these superior fibrous layers forms forward and on each side the broad ligaments. The layers of fibres of the lowerVegion of the body have löst progressively the oblique direction assumed by them at first, and become semicircular. These fibrous layers, which leave the lower portion of the median line, unite on the sides and before the middle region of the uterus to the broad ligaments, an inch below the union of the superior fasciculi. The direction of the fibrous layers of the posterior wall is changed in nearly the same manner as those of the anterior face. These layers, which are at first transverse, are arranged obliquely from above downward, and turn on each side. One portion is attached to the ovary, and then projects on the lateral face of the uterus, and the other passes below these glands to unite forward to the anterior fasciculi which form the round ligaments, whence it follows that not only the fibrous layers of the anterior region of the uterus, but also a portion of the middle layers of the posterior region, contribute to form these ligaments. The median layers, which are arranged longitudinally, extend from the base to the origin of the internal orifice of the neck, loose their vertical direction by separating progressively on the sides, and appear at the end of gestation a kind of tissue of fibres, which intercross, and from whence proceed the other layers of fibres which have been described ( Mémorial de l'art des accouchemens , Paris, 1824). P. T. never seen this mucous membrane, and thinks that the inner face of the uterus is formed only by the extremities of the exhalent vessels which open there. ( Mèmoria . des accouchemens, p. 66.) This explanation is very vague, if not unintelligible. Analogy does not admit us to doubt that the inner face of the uterus is covered by a membrane. F. T. II. ORGANS OF COPULATION. § 2422. The organs of copulation are composed, in the female, of the vagina, the clitoris, the external labia, and the nymphæ ; the three latter have been termed the external genital parts ( pudendum , s. cunnus), in opposition to the others, termed the internal. § 2423. The vagina is a membranous canal, with thin parietes, generally about four inches long and one broad, and larger at its upper than at its lower part ; it is directly continuous with the uterus. Its upper extremity terminates in a cul-de-sac, called the base {fundus vaginae ), and is continuous with the substance of the uterus, embracing its lower or vaginal portion. b. Situation and direction. § 2424. This canal is situated between the rectum, the bladder, and the urethra, to which parts it is united by very loose cellular tissue. It has not the same direction as the uterus, for it descends from behind forward, so that its axis corresponds exactly to the lower axis of the pelvis. § 2425. The vagina is formed of two layers, one external, very thin, solid, and reddish white, which corresponds to the muscular and vascular tunics, is continuous with the fibrous tissue of the uterus, and gradually becomes more solid and vascular from without inward ; the internal is reddish, and is firmly united to the preceding, from which however it may be separated. in virgins. Among these folds we see, particularly on the anterior and posterior faces, a series which is transverse and oblique, situated one above another ( columna rugarum anterior et posterior), which are the conti- B. HYMEN. § 2426. The hymen {hymen, s. valvula vaginœ){ 1) is a semicircular fold of the mucous membrane of the genital parts, formed of tw'o layers united by cellular tissue ; it occupies the sides and the posterior part of the entrance of the vagina, and leaves a greater or less space between its anterior concave edge and the anterior part of the vagina. Not unfrequently this fold arises from all the edge of the canal. Even then however the opening is generally situated forward and rarely in the centre ; the hymen is rarely also thick, hard, solid, and muscular. This membrane separates the internal and the external genital organs, and also the genital and the urinary systems, as we perceive before it the orifice of the urethra, surrounded by small similar folds. § 2427. The clitoris ( clitoris , s. membrum muliebre , s. coles feminarum, s. nympha){2) is an oblong, rounded body, situated below the symphysis pubis. It arises from the upper part of the inner face of the ascending ramus of the ischium by two branches about an inch long, which unite at an obtuse angle. It terminates forward by a small elongated and rounded prominence, called the glans of the clitoris ( G. clitoridis). This enlargement is covered by a thin mucous membrane, and by a thick and soft epidermis, which is easily detached, and it is surrounded by a triangular fold of skin which entirely envelops it. This fold of skin, termed the prepuce of the clitoris ( prœputium clitoridis), which is closed above and open or cleft below, is thin, soft, and moist on its two faces, but particularly on the internal. We remark in it, especially where the prepuce is continuous with the skin which surrounds the glans of the clitoris, a great number of sebaceous glands. (1) A. Vater, De hymene, Wittemberg, 1727. — J. J. Huber, De hymene et raginm rugis, Leyden, 1742. — B. S. Albinus, De hymene ; in the Annot. acad., Leyden, 1758, 1. iv., x. — Goering, De hymene , Altdorf, 1765.— G. Tolberg, De. varietate hymenum, Halle, 1791.— 1. On a more attentive examination we remark that the glans is not a continuation of the substance of the posterior part of the clitoris, but is attached to it only by cellular tissue, vessels, and nerves, and that the posterior part of the clitoris terminates by a concave surface destined only to support it. § 2428. The clitoris is composed of an external fibrous sheath, below which is a spungy tissue formed by broad venous trunks, which frequently anastomose. Thus these lateral parts are termed the cavernous bodies ( C . cavernosa , s. spongiosa clitoridis ). After the two branches by which it arises unite, we observe between its two lateral halves a perpendicular fibrous septum, which separates them imperfectly, and which is directly continuous with the external envelop. § 2429. The branches of the clitoris are covered at the lower part of their edge and on each side by a muscle, which arises directly below their lower extremity by short tendinous fibres ; these are attached to the inner branch of the ascending ramus of the ischium, and extend almost to their other extremity. This muscle is called the ischio-cavernosus muscle (JM. ischio-cavernosus, s. director , s. depressor clitoridis) . D. NYMPHJE, § 2430. The small or internal labia , or the nymphœ ( L . pudendi internez , s. minores , s. nymphœ), are two oblong, reddish, corrugated folds, similar to the crest of a cock, and very much compressed from right to left ; they are connected posteriorly, and their anterior extremities unite in the glans of the clitoris. The skin which covers them is very delicate, soft, moist, destitute of hair, and similar, especially on its innerside, to a mucous membrane. Hence it follows that the nymphæ divide at their anterior extremity into two branches ; the internal, which is the smaller, enters into the glans, and the external, or the larger, terminates in the prepuce, and their spungy tissue unites with that of the glans. E. EXTERNAL LABIA. § 2431. The great or external labia ( L . pudendi externa , s. magna ) are considerable folds of skin, directed from before backward, which envelop the other external genital parts. Their external fold is formed by the skin : the internal by a very thin mucous membrane, which is continuous with that of the nymphæ. They unite anteriorly and posteriorly, thus forming the anterior and posterior commissures. They are imperceptibly continuous forward with the mons veneris. They are united posteriorly, on the inside and above the posterior commissure, by a thin and transverse fold, termed their frenum ( frenulum pudendi). T. MUCOUS CRYPTS OP THE EXTERNAL GENITAL PARTS. § 2432. The external genital parts are provided with numerous large mucous crypts ; they abound particularly around the orifice of the urethra and the entrance of the vagina. The first have been termed the prostate of Bartholini {prostata Bartholiniana).{\) § 2433. The upper extremity of the external genital organs in the female is surrounded on a level with the nymphæ by a thin, long, round, and muscular layer, which blends posteriorly with the anterior extremity of the sphincter ani externus muscle, and is attached forward to the branches and the body of the clitoris. This is the constrictor vaginae muscle (JVf. constrictor cunni). III. VESSELS AND NERVES. § 2434. The female genital organs receive their vessels from two sources, principally from the spermatic arteries and the branches of the hypogastiic arteries ; they are termed the uterine and vaginal arteries, and the arteries of the clitoris, and they are distributed in the parts of the same name. Some twigs of the internal pudic artery also go into the external labia. gastric, and the renal veins. The spermatic vessels form around the ovaries a very complex plexus, called the pampiniform body ( plexus pampiniformis). They anastomose in the substance of the uterus not only those of one side with those of the other, but those of the upper part with those of the lower. IV. PROPERTIES AND FUNCTIONS. § 2435. As the external genital parts of the female receive a great number of nerves, they possess an extreme sensibility, which does not exist to the same degree in the internal. (â) Prévost and Dumas assert (Mémoire sur la génération dans les mammifères et les premiers indices du développement de l’embryon ; in the Annales des sc. nat,, vol. iii., p. 134) that fecundation does not take place in the ovary, because we never find in the pouch covering this organ the spermatic animalculæ, which are considered the agents of fecundation; so that according to them the moment of fecundation is much later than that of copulation, and the ovum is not impregnated until arriving in the Fallopian tube or the uterus it comes in contact with the seminal fluid. How can this theory be reconciled with ovarian pregnancy 7 F. T. 1st. The fetus is developed in the uterus, when no anomaly occurs. 2d. Even when the fetus is developed out of the uterus, the latter undergoes the usual changes in its substance and its cavity. The possibility of extra-uterine fetation, however, proves that it is not absolutely necessary to form the new organism. coition. This increase of susceptibility communicated to the internal genital organs and to the organism is attended with the degree of energy or excitement necessary to produce the new being. § 2437. The testicles have an elongated, rounded, and an almost oval form. They are situated at the lower part of the trunk, on the sides and below the penis, in a special fold of the skin which is formed like a sac, and is termed the scrotum. They communicate wfith the parts of the genital apparatus situated within the abdomen, by the spermatic cord ( funiculus speculations, s. testicularis). (1) R. de Graaf, De virorum organis generations inservientibus, Leyden, 1668. — Leal Leali, De partibus confie ientibus in viro, Padua, 1686. — Santorini, De virorum naturalibus ; in the Obs. anat ., cap. x. — J. G. Rœderer, De genitalibus virorum, Gottingen, 1758. — J. Wilson, Lectures on the structure and physiology of the male urinary and genital organs of the human body , London, 1821. § 2438. The testicle 'alone, that is its substance, when its envelops, except the most internal, are removed, is generally an inch and a half long, one broad, and about nine lines thick. 1. Skin of the scrotum. § 2440. The external layer is the skin of the scrotum, a fold of the common integuments, which descends from the inguinal region, and terminates between the roots of the penis and the perineum. This fold, which is broader at its lower than at its upper part, differs from the rest of the skin, as it is generally a little darker colored, since it presents distinct hairs, and because there is no fat. It presents also exactly on the median line a narrow sac, the direction of which is from before backward ; this is slightly prominent, and is formed by numerous transverse folds arranged very compactly, and is termed the raphe. Although apparently thicker at this part, the scrotum is in fact thinner than in any other. 2. Dartos. § 2441. Immediately under the skin we find the dartos ( tunica carnea , s. dartos ), which is situated, in regard to the skin of the scrotum, in the same manner as the adipose substance is in regard to the common integuments, excepting, however, in men who are very fleshy. dently fibrous. As it is also very contractile, several anatomists, as (1) J. E. Neubauer, De tunicis vaginalibus testis et funiculi spermatid dissertatio, Giessen, 1767. — A. Monro, Remarks on the spermatic vessels and the scrotum , with its contents ; in his Medical essays, vol. v., pt. i., p. 205-222. — J. Brugnone, De testium in fœlu positu, eorum in scrotum descensu, tunicarum quibus continentur, numéro et origine, Leyden, 1788. — P. A. Bondioli, Sul numéro delle tonache vaginali del testicolo, Padua, 1780. — J. Tumiati, Richerche anatomische intorno alle tonache dci testicoli, Venice, 1790. Winslow,(l) have considered it as muscular, and have compared it to the subcutaneous muscles ; but accidental or designed emphysema, (2) and the comparative results obtained by macerating it and the platisma myoides muscle, show nothing but cellular tissue. (3) Probably, however, it makes the transition from the mucous to the muscular tissue, and there is between it and the other muscles, about the same relation as between it and the muscles of the superior and inferior animals, in whom the fibrous structure is not very distinct, and is concealed in some measure by the gelatine, an element of muscous tissuej which envelops and conceals the fibrin instead of leaving it exposed, as in the superior animals, where even it is not changed into this substance. § 2442. The dartos forms tw'o distinct sacs, which are adapted to each other on the median line, and give rise to the septum of the scrotum {septum scroti) which corresponds to the raphe. It consequently separates the two testicles, not only in respect to position, but also, and to a certain extent, in that of vitality, although they are not perfectly distinct. Like the mucous tissue in general, it is more or less infiltrated with serum. 3. Cremaster muscle. § 2443. The cremaster muscle, the fleshy or erythroid tunic ( tunica carnea, s. erythroides ), is situated below the dartos ; it arises from the horizontal ramus of the pubis, and forms a third layer. This tunic is formed by an external fasciculus, which descends from the lower edge of the two internal broad abdominal muscles, and by an internal fasciculus, which is generally smaller, but is sometimes as large, and rarely larger; this arises from the horizontal ramus of the pubis. It surrounds the spermatic cord, and the internal tunics of the testicle, and is distributed principally on the anterior face, even when it embraces all the surface of the organ. Its fibres describe arches which are convex downward, and separate more from each other the lower they descend. When there are muscular fibres on the whole surface of the organ, the spermatic cord emerges through the inferior part of the obliquus internus muscle, and not only below its inner edge. Sometimes the internal fasciculus is really or apparently deficient ; the latter case is most common. Sometimes in muscular persons, but very rarely, fasciculi leave the cremaster muscle, and go with the spermatic cord into the abdominal cavity.(4) It is itself enveloped by a prolongation of the thick cellular sheath ■which surrounds the obliquus abdominis externus muscle, and its fibres, although separated are united by cellular tissue. This cellular tissue and the cellular sheath which we have mentioned, blend together below, where they alone envelop the testicle, below which they unite with a common vaginal tunic, to give rise to a short but solid tubercle. 4. Common vaginal tunic of the testicles and spermatic cord. § 2444. Next to the erjhhroid tunic is a layer of mucous tissue, termed the common vaginal tunic of the testicle and spermatic cord ( tunica vaginalis testis, et. funiculi spermatid communis ). This tunic arises from the mucous tissue which surrounds the peritoneum, and covers the whole cord and testicles : we may by inflating its lower extremity, pass air through the inguinal ring into the cellular layer which covers the anterior and posterior faces of the peritoneum, and even between the layers of the mesentery. Prolongations proceed inward from the external edge of this layer, and go toward the interior, where they unite together the vessels of the spermatic cord and the vas deferens, but we do not find below it the pretended proper vaginal tunic of the spermatic cord ( tunica vaginalis funiculi spermatid propria ), which Neubeauer admits and which he asserts has a distinct cavity, for if after carefully removing this layer from its external surface, the vessels of the spermatic cord be inflated, this air penetrates into every part ; and farther, air injected into it, also enters the vessels of the cord. Farther, the common vaginal tunic cannot be considered at its upper part as a special, independent and close serous cylinder, if we reflect, that on removing the cremaster muscle which covers it, it ceases to be impermeable to the air, and that it presents this character only so long as it is surrounded by the muscle and its tendon. We can at most admit an external layer, similar to the loose layer of the serous membranes, and a reflected fold which surrounds and unites the vessels of the spermatic cord. The first then will be termed the common, and the second the special tunic of the cord. But below, as far as it covers the proper vaginal tunic of the testicle, thi3 tunic is very firm, evidently fibrous, and adheres intimately to the proper tunic of the gland, especially near its lower extremity. 6. Proper vaginal tunic of the testicle. § 2445. We must distinguish from this layer the fifth envelop of the testicle, th e proper vaginal tunic ( t . vaginalis testis propria), from which it is perfectly separated. This tunic is a compound serous membrane. It usually has an oval form, similar to that of the testicle ; it however is rather more extern sive, so that its cavity is a third higher than - the gland, being two inches and a half high. Sometimes a narrower prolongation, which varies in length, leaves the anterior part of its surface, and penetrates below into the common vaginal tunic, and the two cavities uninterruptedly communicate. The special vaginal tunic receives in its cavity not only the testicle, but also the whole epididymis and a portion of the spermatic cord. At the place where it is reflected on itself, it receives directly these last two parts in thé commencement of its internal and reflected fold. When it has enveloped them, it passes on the upper and lower extremity of the testicle, but covers the gland in its greatest portion, so that the summit and the base of the epididymis are only covered by it in the point by which they look toward the testicle. Thence it goes on the whole circumference of the gland. It is by this fold that the spermatic vessels pass to go to the testicle, and enter at its upper and posterior edge. The two layers which form this fold are slightly united by cellular tissue, so that they are easily separated. It is not difficult to detach the vaginal tunic from the epididymis ; but it is less easy to separate it from the testicle, excepting for some lines near the posterior edge. A portion of this membrane which covers the testicle, has been improperly termed by Tumiati,(l) the conjunctiva. It is usually called the external layer of the tunica albuginea, a term still more inconvenient. 6. Fibrous or albugineous tunic. § 2446. The fibrous or albugineous membrane ( T. albuginea , anonyma, fibrosa) is the last and the most internal tunic of the testicle. It directly envelops the substance of the gland, and determines its form. It is thick, solid, silvery, shining, and fibrous. In fact, it is a fibrous membrane . § 2447. On the inner side of the albugineous membrane, to which it adheres in great part but slightly, is the substance of the testicle,(l) a soft brownish yellow mass, divided by the blood-vessels of the tunic into several lobules ( lobidi),{2 ) situated one above another. This substance is composed principally of very many minute canals, which are single, and do not ramify and interlace with each other ; they are termed the seminal canals ( canaliculi semmales, s, vascvla serpentina , s. ductus seminiferi). Each lobule includes one of these canals. Their circumvolutions, and they themselves, are united very loosely by a fine cellular tissue, so that they may be easily detached. But it is much more easy to prove by maceration, their very great number, which is about three hundred. Each of them is about sixteen feet long and broad. If attached to one another, they would consequently extend about five thousand feet. § 2448. These canals unite near the upper extremity of the testicle, into several larger canals, which pass through the albugineous tunic, and soon produce about twenty others, which are still larger, called the vasa efferentia. These latter are united in a single fasciculus by a mucous tissue, wind around from below upward, and form the rounded and enlarged head of the epididymis. B. EPIDIDYMIS. § 2449. The epididymis{ 3) is the commencement of the excretory duct of the testicle. It begins at the upper extremity of this gland by a thicker, enlarged, and rounded part, called the head , and descends along its posterior and upper- edge. The fasciculi which form the seminal passages, are still separated in the head of the epididymis, although, according to our observations, this part seems to be perforated, even at its upper extremity, only by a simple and very tortuous canal, into which the seminal passages severally open. The thinnest and longest part of the epididymis, that termed its tail ( cauda ), is a simple, but very tortuous canal ; it is at first very narrow, but gradually enlarges very much, and becomes more tortuous. It is but loosely attached to the proper vaginal tunic of the testicle by a fold of this membrane, and is reflected on itself from below upward at its lower extremity, and is then called the ductus deferens. It is about thirty feet long. (1) A. Haller, De vasis seminalibus observationes, Gottingen, 1745. — A. Monro, Description of the seminal vessels ; in the Edinb. essays phys. and literary, yo\. i. xvi. — Id., De testibus et de semine in variis animalibus , Edinburg, 1755. — Id., Of the seminal ducts ; in the Observations anatomic, and physiol, wherein Hunter’s claim some discoveries is examined , Edinburg, 1753. — G. Prochaska, Beobachtungen über die Samengange ; in the Abhandl. der Jos. Akad., vol. i. p. 198-213. C. DUCTUS DEFEHENS. § 2450. The ductus deferens or vas deferens, ( 1) ascends along the posterior and upper edge of the testicle, first in a straight line, then obliquely from within outward. It is tortuous at its origin, but soon becomes straight, and joins the spermatic vessels, with which it is united by cellular tissue, to give rise to the spermatic cord. It ascends directly to the inguinal ring ; but in this place its direction changes, and it goes from below upward, and from within outward in the inguinal canal, within which we observe the relation we have indicated, between the blood-vessels and the lymphatics, and the ductus deferens. On leaving this canal it crosses the epigastric artery, and ascends directly before it, then turns behind it on the inside, and upward, and thus comes into the abdominal cavity. Thence it leaves the spermatic vessels at a more or less acute angle, goes inward and downward always on the outside of the peritoneum, which covers only its posterior part, and descends into the small pelvis, converging very much toward that of the opposite side. It dilates and gradually thickens in its course. At its lowest part, which suddenly dilates considerably, it becomes at the same time very tortuous, less so, however, than at its origin, and gives rise on the outside upward and backward, to a great enlargement, to a kind of purse or cul-de-sac, termed the seminal vesicle. Two very different substances enter into its composition. The external, which is about half a line thick, is of a brownish yellow color, very hard and solid. Very probably it is irritable, although fibres are distinctly seen in it very rarely. Sometimes, however, we have observed circular fibres which it was impossible to mistake.(2) The inner substance is whitish, and easily separable from the preceding, with which it is united only by a loose cellular tissue. It is a mucous membrane, a prolongation of that of the urethra. It is smooth in most of its extent, but reticulated below for an inch or turn. D. SEMINAL VESICLES. § 2452. The seminal vesicles ( vésicules séminales, s. parastatœ)( 3) are situated one on each side, on the outside of the corresponding ductus deferens. They are also intimately adapted to the posterior face of the bladder, and are covered posteriorly by the perito- neum which adheres to them but slightly. Their breadth is, however, slight in proportion to their length, for they are about two or three lines broad, and four or five inches long; but they appear much shorter, as they are very tortuous. They are, however, not always simply tortuous or similar to a long cul-de-sac, as Lealis, and since his time Caldani,(l) have asserted. In fact, they more commonly ramify. Their inner membrane presents numerous inequalities, which produce a kind of net-work with irregular meshes. There is also between the largest folds, a considerable number of less prominent folds, which also render their inner face still more uneven. This arrangement establishes a striking analogy between the seminal vesicles and the gallbladder. § 2453. The lower, extremity of the seminal vesicle and of the ductus deferens, opens into an extremely narrow duct some lines long, termed the ejaculatory duct ( ductus ejaculatorius). This duct approaches from behind forward, and from below upward, that of the other side, enters into the substance of the prostate gland, and opens into the urethra, directly at the side of this latter, in the centre of the verumonianum. E. PBOSTATE GLAND. § 2454. The prostate gland ( prostata ) is a triangular (2) body, usually of the size and form of a chestnut ; is about an inch broad, one high, and half an inch thick, and weighs about five drachms. posterior and smaller. The middle lobe is situated behind and between the two lateral lobes and the ejaculatory ducts, and likewise between these latter and the bladder ; it is rounded and smaller than the lateral ; its volume however varies. In the centre of its lower face is an oblong rounded eminence, which terminates anteriorly in a narrow and elongated point. This eminence has been termed from its form, the verumontanum ( caput gallinaginis , s. verumontanum, s. colliculus seminalis). It presents at its centre one or two orifices of the ejaculatory ducts, and on the sides a considerable number of orifices leading to the excretory canals, -which are distributed in the substance of the glanfl. These orifices give passage to a yellowish fluid, the fluid of the prostate , which mingles with the semen at the time of emission. § 2455. The penis (penis, s. coles, s. priapus, s. membrum virile ) is situated forward, and entirely on the outside of the pelvis, below the symphysis pubis, between the thighs. Its form is nearly cylindrical. The common excretory duct of the urine and semen, the urethra , passes through it. It is entirely surrounded by a prolongation of the skin, which in this place is thin and destititute of hairs, and fat. External examination shows even through the skin, that it suddenly enlarges at its anterior extremity, where it presents a considerable prominence, and that it terminates in a blunt point.(l) a. Gians. § 2456. This enlarged portion is the glans penis, (2) a rounded triangular body, terminated posteriorly by a rounded sac, termed the crown ( corona glandis ), which entirely surrounds it, and forward by a longitudinal groove, the external orifice of the urethra. The contracted portion, situated behind the glans, is its neck. b. Prepuce. § 2457. The first two layers are united by cellular tissue, so that the external is turned outward, and the internal inward. They form th e prepuce (preputium). This fold is fitted to the glans, but is not attached to it, so that it can be drawn backward and forward ; the first motion exposes the glans, the second covers it. the prepuce presents apparently a rounded opening, which corresponds (1) F. Ruysch, Responsio, &c. in the epist. xv. De vas. sanguineorum extremit., &c. Iiisce accedunt nonnulla circa penem detecta. — B. S. ii. c. xi. — F. ii. c. xiii. — L’Admiral, Iconpenis humani cera præparati, Amsterdam, 1741. — J. H. Thaut. Diss. de virgae virilis statu sano el morboso, Wurzburg’, 1808. to the anterior oiifice of the glans, and which disappears when the prepuce is drawn entirely backward. The latter is corrugated transversely in the same proportion. The internal layer of the prepuce is reflected a second time behind the glans, but here from behind forward, and covers this organ, intimately adhering to its tissue. This adhesion is almost gradual on the circumference of the glans. In fact the internal fold of the prepuce is loose at its upper part, where it is attached but feebly to the penis ; but near the centre of its lower part, it is tense, short, and intimately united to the corresponding portion of the glans, and forms a short perpendicular fold. All around the neck and posterior face of the crown, the most internal cutaneous fold of the glans presents numerous rounded depressions, termed the glands of Tyson ( glandulœ Tysonianœ), which secrete a thick and whitish fluid. loosely. It is composed of a thick and fibrous membrane, which determines its form, and of a spongy tissue, principally formed by dilated veins, which is then divided into three distinct bodies. The two upper and lateral are termed the cavernous bodies of the penis ( corpora spongiosa, s. cavernosa , s. nervosa penis), the inferior is termed the spungy body of the urethra ( corpus spongiosum , s. cavernosum urethrae). The cavernous bodies of the penis and urethra are generally described as a collection of different cellules of the vessels ; but these cellules are in fact only dilated veins, and the spungy bodies are composed of a very complex net-work of arteries and veins, as Vesalius(l) and Maipighi(2) had already stated generally in regard to the penis, and Hunter, (3) of the spungy body of the urethra particularly. (1) De corporis humani fabricà, lib. v. c. xiv. Corpora have... enata ad eumfere modum, ac si cx innumcris arteriarum. venarumquefasculis quam tenuissimis, si uiulquc proximé implicatis, retia quœdam efformarentur, orbiculatim a nervea ilia ■membrane aque substantia comprehcnsa. (2) Diss. epist. varii argumenti ; in the Opp. omn., vol. ii. p. 221. Sinuum speeiem in mammarum tubulis et in pane habemus ; in his nonnihil sanguinis reperitur, ita ut videantur venarum diverticula , vel saltern ipsarum appendices. terlace with each other, and are longitudinal. They arise on each side by a branch about half an inch long, which comes from the ascending ramus of the ischium ; the two branches ascend to meet each other, and unite before the symphysis pubis, where they are surrounded in their whole circumference by a common envelop. Although they appear simple externally, these bodies are however imperfectly divided into two halves, a right and a left, by a perpendicular septum ( septum corporum cavernosorum ), which extends almost fheir whole length, and is a prolongation of the external fibrous membrane. This septum is formed of very long fibres, compressed from right to left, which extend the whole heigth of the cavernous bodies, and which, forming posteriorly an almost perfect septum, proceed forward, growing thinner, and diminishing much in number so as to leave between them greater or less spaces. The separation which takes place between the two cavernous bodies at their posterior extremity, then gradually disappears forward entirely. They however separate still more at their anterior extremity, although apparently only on the outside, since the external part of their circumference is much longer than the internal, whence their anterior faces, surrounded by the external tunic, unite from without inward at a re-entering angle. it contracts much for about an inch, so as to be only one or two lines in diameter. This contracted portion is called the isthmus of the urethra (isthmus urethrcc). It ascends a little obliquely from below upward, and from behind forward, below the symphysis pubis, from which it is about an inch distant, surrounded by a loose spungy tissue, like the urethra in the female, which corresponds only to this portion of the urethra in the male. The canal afterward enlarges very much, and is then surrounded in the rest of its extent by the cavernous body of the urethra, the size of which is generally in direct ratio to its diameter. The cavernous body of the urethra is largest at the second prominence, where it forms a considerable enlargement called the bulb oj the urethra (bulbus urethrcc) . On leaving this point the urethra contracts very much. Its diameter continues about the same to the anterior extremity of the penis ; but directly behind and within the glans it enlarges a third time to form the navicular fossa ( fossa navicularis) . The cavernous body of the urethra is enveloped only by a dense cellular tissue, which is not fibrous. It is finer, and of a more delicate tissue than that of the penis, and has no septum. It alone forms the glans anteriorly. These cavities are sometimes three lines deep. They are seen only at the lower part of the circumference of the urethra, and their direction is such that their orifice looks forward and their cul-de-sac backward^ 1) (1) As Ducamp’s researches have reduced the treatment of strictures of the urethra almost to mathematical accuracy, it is necessary to have a more extensive knowledge of this canal than has been given by Meckel. This may be found in a memoir of Amussat ( Remarques sur l'urètre de l’homme et de la femme ; in the Archiv, gén. de mêd ., vol. iv., p. 31 and 347), who has ascertained a very important practical fact, that even in young subjects the urethra is straight or nearly straight when the rectum is empty, and the penis is directed from before backward. We distinguish in it three portions : the prostatic portion, with thin parietes, which is enveloped by the prostate gland ; it is about twelve or fifteen lines long; the membranous portion, the parietes of which are a little thicker ; it is from nine to twelve inches long ; and the spungy portion, which is from about six to seven inches long. Most authors consider the whole canal as ten or twelve inches long ; but it is only nine, and very frequently, at least sometimes, even less than eight, as has been stated by P. Whately (An improved method of treating strictures in the urethra , London, 1816, p. 68). We may then estimate its mean length as between eight and nine inches, nine inches and six lines and seven inches and six lines being the two extreme proportions observed by Whately in forty-eight different subjects. It is not equally broad in every part. It follows, from Sir E. Home’s researches (Practical observations on the treatment of strictures in the urethra , London, 1805, vol. i., p. 24), that its diameter is four lines in most of its extent, and that its external orifice is at least one line narrower, since it is only from two and a half to three lines in diameter. Amussat has since proved that the urethra, when the parts which cover it are removed and it is reduced almost to the mucous membrane, represents a cone, the base of which is turned backward, and which is slightly prominent at its membranous portion, contracts opposite the bulb to enlarge suddenly at the commencement § 2462. Besides the testicles and the prostate gland, we also frequently, but not always, find two or three other small, yellowish, oblong, rounded, hard glands formed of several lobes enveloped by a very dense aponeurotic sheath. These glands are about the size of a large pea, are situated directly below the upper part and a little before the prostate gland. canal by distinct orifices. The two posterior lateral are termed the glands of Cowper. {V) The anterior, which is unmated, is smaller and much less constant than the other two ; it is termed the anterior prostate gland ( antiprostata .) a. Special muscles of the penis. § 2463. The penis has three muscles, one of which, the ischio-cavernosus , belongs to the cavernous bodies of the penis, the second, the bulbo-cavernosus , belongs to the spungy body of the urethra, while the third, the constrictor urethrae muscle, moves the membranous portion of this canal. All three are situated at the extremity of the penis. § 2464. The ischio-cavernosus muscle, ischio-uretral , Ch. (JW. ischiocavernosus ■, s. erector penis), resembles that of the clitoris in its origin, attachments, direction, and mode of action ; but it is much larger, and sometimes arises by a second head from the sciatic tuberosity. of the spungy portion, and diminishes imperceptibly to the meatus, so that there is no enlargement in the place corresponding to the glans, that is, in the navicular fossa. Amussat explains the appearance of an enlargement in thi3 latter point, by saying that the tissue of the glans is less soft and the mucous membrane is attached to it more intimately, so that in dividing the urethra, the two halves of the glans remain firm and distinct, while the proper spungy tissue contracts and collapses, being freed from the blood within it. That the navicular fossa is only apparent is proved by extending transversely the spungy portion behind the glans, when it becomes as broad as that situated in the body. He has also given a very exact plate of the urethra ( loc . cit., pi. iii., fig. 1 and 2). P. T. (1) G. Cowper, Glandularum quarumdam nv.per detectarum descriptio, London, 1702. — L. Terranus, De glandulis universim et spedatim ad urethram virilem novis, Leyden, 1729. — G. A. Haase, De glandulis Coicperi mucosis, Leipsic, 1803. § 2465. The bulbo-cavernosus muscle, bulbo-uretral, Ch. (JM. accelerator urinœ, s bulbo-cavernosus ), is thin, flat, and nearly rhomboidal. It surrounds the bulb and the posterior part of the urethra. It arises forward from the posterior part of the cavernous body of the penis, and backward from the upper part of the lateral wall of the bulb of .the urethra. It terminates anteriorly by a straight edge, which descends from without inward and from before backward, and posteriorly by a rounded edge. It is formed at its anterior part by very oblique fibres, and at its posterior part by fibres which are nearly transverse. It blends on the median line with that of the opposite side so intimately, that frequently they are not separated by a median tendinous line. § 2466. The constrictor urethræ. muscle, pubo-uretral , Ch. (JM. constrictor urethrae, s. pub o-urethr alls), ( 1) is elongated, quadrilateral, and flattened from without inward. It arises by a short tendon a little above the lower edge of the symphysis pubis, some lines below the tendinous attachment of the bladder, directly at the side of the tendon of that of the synonymous muscle, on the inner face of the symphysis. Thence it descends enlarging, is first next that of the opposite side, but removes from it on arriving at the membranous portion of the urethra, to which it is attached, and below which it is blended with its synonymous muscle, so that generally only a tendinous line, corresponding to the median line, indicates their separation. It is frequently united at its lower part by some fibres to the levator ani muscle ; but in the rest of its extent it is separated from it only by veins, which arise from the prostate gland and the bladder, proceed from behind forward, and empty into the great dorsal vein of the penis. The two muscles form a ring around the membranous portion of the urethra ; they compress it, and by their convulsive contractions very much increase the difficulty of passing a sound through this portion of the canal. a. Transversi perinei. § 2467. We usually find two muscles on each side, the transversi perinei muscles, iscliiu perineal, Ch., which go inward from the ischium and the pubis, and which are similar, as they are .both long. § 2468. The posterior and inferior arises from the inner face of the sciatic tuberosity, goes from without inward and from behind forward, and blends particularly in the female with that of the opposite side and with the anterior extremity of the sphincter ani externus muscle, and slightly also with the posterior extremity of the bulbo-cavernosus and the constrictor vaginae muscles. the expulsion of the feces. § 2469. The anterior and superior arises from tlie inner face of the lower part of the descending ramus of the pubis, where it is frequently united intimately to the preceding, goes inward and a little forward, blends again with the preceding, that of the opposite side, and the sphincter ani externus muscle, and likewise with the bulbo-cavernosus and the constrictor vaginæ muscles, farther forward than that we have mentioned. the posterior part of the urethra, and in the female the vagina. § 2470. The posterior transversus perinei muscle is frequently deficient. In man the two muscles are much nearer each other and much slighter than in the female. In the latter we sometimes find a third, situated between the other two. § 2471. The levator ani muscle, sous-pubio-coccygien , Ch., is broad, thin, and semicircular. It arises forward and upward from the lower part of the symphysis pubis and the horizontal ramus of the pubis ; it also comes from the inner face of the body of the ischium to the sciatic spine, above and on the inside of the upper edge of the obturator internus muscle. Thence it goes inward, downward, and backward, so that its anterior fibres are almost perpendicular and the posterior transverse. It passes behind the lower part of the rectum, and is attached by short tendinous fibres to the lateral edge of the three lower pieces of the coccyx by the posterior part of its inner edge, while by the anterior it blends with that of the opposite side. It follows from this arrangement that the two muscles form a large ring, which surrounds the lower extremity of the rectum posteriorly, and which in the female is attached very intimately to the vagina before arriving at the rectum. pubis is often separated from the rest. This muscle raises the lower part of the rectum, contracts it, and thus prevents the prolapsus of the intestine, also favors the expulsion of the feces, carries' forward and upward the coccyx, which has been pushed forward by the feces and excrements, and by the fetus in parturition, favors the expulsion of the urine and semen by compressing the bladder and seminal vesicles, and finally prevents prolapsus of the vagina in females. III. VITAL PROPERTIES AND FUNCTIONS OF THE GENITAL ORGANS IN THE MALE. § 2472. The testicles secrete the semen, and are the most important part of the genital organs, since the action of this fluid on the body of the female can alone cause the formation of a perfect new organism. This is demonstrated by sterility occurring when these organs are extirpated, are congenitally absent or diseased, although the other genital organs are formed normally. The 'testicles also perform an important part in the individual organism ; for when they do not exist, or when they have been removed, the body and the mind vary more or less from the normal state, the larynx and the voice are not developed, the beard does not grow, in short the individual does not acquire the distinctive characters of his sex. The semen is carried from the testicles through the ductus deferens into the seminal vesicles, where, like all the other fluids in their reservoirs, it continues a certain time, becomes perfect, and is concentrated by the absorption of its aqueous portion, (2) and perhaps is somewhat modified by mingling with a fluid secreted in the parietes of the vesicles. (1) Yauquelin, Annales de chimie, vol. ix., p. 64. — Berzelius states ( Annales de chimie, vol. lxxxviii., p. 115) that the semen is formed of a peculiar animal matter and of all the salts of the blood. rally admitted opinion, and assert that the seminal vesicles do not receive the semen, but they only secrete a peculiar fluid supplied by the testicles, and some of them, as Wharton, have considered it as the proper semen. They adduce the following arguments : 5th. The fluid contained in the seminal vesicles differs from the semen, both in man and animals ; it is much brighter and more liquid, and has not the peculiar odor of semen. (5) 7th. In males who have lost one testicle, (7) or in whom one of the testicles does not communicate with its seminal vesicle, this latter and even the lower part of the ductus deferens of the same side have been found not contracted or empty, but, on the contrary, larger and fuller than that of the opposite side. (8) London, 1786, 1792, p. 31. — Chaptal, Mém. où Von se propose défaire voir que les vésicules séminales ne servent pas de réservoir à la semence séparée des testicules ; in the Journal de physique, 1787, p. 101. 5th. The difference between the liquid in the vesicles and the semen emitted, may depend on a mixture of their proper secretion with that of the testicles. Farther the semen ejaculated is composed of the fluid of the testicles united with that of the seminal vesicles, the prostate gland, the glands of Cowper, and the mucous membrane of the urethra. 6th. It does not follow from this that the liquid ejaculated has not passed from the testicles into the seminal vesicles. Possibly, the fluid expelled during efforts to go to stool, comes from the prostate gland and even from other parts, as a similar thing occurs in dogs which have no seminal vesicles. (2) 7th. Possibly this effect was accidental, which is more probable, since the gall-bladder, when the bile is prevented by a calculus from entering, is often distended to a great degree by the mucus which it secretes. 8th. This opinion is often opposed, at least by experience. Farther when this is not the case it would only prove that the venereal orgasm increases also the action of the testicles, and that the semen emitted comes not only from the vesicles, but also from the glands themselves. 9th. The assertion is not correct, and proves nothing. Even Hunter admits that the seminal vesicles take part in the genital act, so that their uniform depletion under different circumstances is not more surprising, whether the fluid comes from the testicles, or is secreted by the vesicles. 10th. The absence of the seminal vesicles in several animals, does not prove that the semen is not introduced into the reservoirs when they exist. Farther, a communication between the vesicles and the vasa deferentia, really exists in several animals where it is not admit- (1) De Graaf, Partium gcnitalium defensio, Leyden, 1673.— Needham, Croone, and King-, in Birch, Hist, of the ray. society , vol. iii., p. 103. — Brugnohe, Observations anatomiques sur tes vésicules séminales tendantes à en confirmer l’usage ; in the Mém. de Turin , 1786-1787. — Soemmerring, Anmerkungen über Hunter's Aufsatz ; in Blumenbach, Medic. Bibi ., vol. iii., p. 87. t ed by Hunter, as the guinea-pig and the horse, while the pretended seminal vesicles, which according to others do not communicate with the excretory passages of the vesicles, are protsate glands. 14th. The substances injected into the vesicle generally emerge through the ejaculatory passage before arriving at the ductus deferens, and frequently do not penetrate at all into the latter. (2) 15th. The air and sounds introduced through the orifice of the ductus deferens, easily penetrate into the vesicle, but with difficulty into the ejaculatory passage. Notwithstanding this refutation of Hunter’s opinion, we cannot deny that the proper secretion of the seminal vesicles seems to contribute powerfully to elaborate the semen. § 2474. The semen comes into the urethra and directly into the prostate gland, where it mingles with a more serous and yellowish white fluid secreted by this gland, and which also contributes to perfect it.(3) § 2475. The penis possesses in a great degree the power of enlarging and lengthening by the excitement of the venereal passion. It also becomes hard and stiff, which depends undoubtedly on the dilatation and tension of its fibrous envelop. Its power of erection depends on the peculiar arrangement of its vessels ; when erected it can enter into the vagina of the female; it fills this canal more or less perfectly, and injects the semen into the internal organs of generation, particularly the uterus. The erection of the penis depends on the great excitement of the nervous action, either in the whole system or in the nerves of the penis, which are proportionally very large ; a greater quantity of blood is then carried into it by the arteries, and is not resumed by the large and numerous veins of the organ, as rapidly as it flows into it. It has been asserted that the phenomenon of erection ought not be explained thus by the accumulation of blood, (4) but this opinion is- completely refuted by the experiments,(5) in which, on cutting the penis when erected, after tying its base, the venous plexuses are found gorged with blood. § 2476. The first changes which cause the emission of semen, undoubtedly take place in the glans, since it possesses the most nerves, and is the most sensible part, not only of the penis, but of the whole genital system. The excitement of the nervous action in this part is extended to the whole nervous system, particularly to the nerves of the genital organs, quickens the secretion of the testicles, the seminal vesicles, and the other glands, and causes convulsive motions in the bulbo-cavernosi muscles, which compress the spermatic fluid when it arrives at the posterior part of the urethra, and throw it by jets into this canal, which is rendered straight by the erection of the penis. II. MAMMAE. § 2477. The mammcc{ 1) are the accessory parts of the genital system, which in man and in all true mammalia, establish a natural relation between the organism of the mother and that of the child, by means of the milk which they secrete, which continues during the early periods of life. In birds, and perhaps also in some reptiles, there exists a similar connection between the mother and the offspring, which continues a longer or shorter period after the birth of the latter. But in these animals it does not occur by a special organ, having the power of secreting a peculiar nutritious fluid. It is only by a portion of the intestinal canal, the crop ( ingluvies ), which undergoes about this period a change analogous to that which occurs in the mammae, but which, however, serves for the mother and the offspring. gans, conglomerate glands. Although regularly, they fulfill their function only in the female, they occur also in the male, where they are much less developed ; the mammae of the male, however, are sometimes as large, and their secretion as abundant as those of the female. geni, Brunswick, 1796, p. 17. (1) A. Nuch, Adenographia curiosa, Leyden, 1691, c. ii. — Mencelius, De structura mammarum, Leyden, 1720. — Guntz, De mammarum fabrica et lactis sccretione, Leipsic, 1734. — Bcehmer, De ductibus- mammarum lactiferis , Halle, 1742. — Kcelpin, De structura mammarum, Gripswald, 1764. — Crusius, De mammarum fabrica et lactis secretione , Leipsic, 1785. — Covolo, De mammis ; in Santorini, Tabul, septemd., p. 92-110. — Girard, De mammarum structura ; ibid., p. 110-116. — A. Joannides, De mammarum physiologia, Halle, 1801. § 2479. They are situated opposite to one another, one on each side, on the anterior face of the chest, and the region which they occupy in the female is termed the mammary region ( regio mamma). The glandular substance which forms their base, is surrounded by a great quantity of fat, which gives them a semicircular form. Their base, however, is not perfectly circular, but rather eliptical. It extends particularly upward and outward, and often to the region of the axilla ; it is more circular below and inward. It extends from the third to the seventh rib, and covers most of the pectoralis major muscle ; but not unfrequently the most external portion of its lower edge covers also a portion of the serrât us magnus muscle. The edge of the mammas is not smooth in every part, nor is its thickness uniform. In those females wrho have borne several children, it presents inequalities, because the gland enlarges irregularly outward, so that irregular prolongations leave its edge. Nor is the circumference of the mammae smooth in every part. It presents in every part analogous prolongations, differing in form, size, and direction, which render its surface uneven, and leave between them greater or less depressions. The lower and internal part of these glands is much thicker than the upper and external. A little below the centre of the mammæ, in its thickest portion, we perceive a more or less prominent eminence, termed the nipple ( ma milia, papilla mamma), which is surrounded by a more colored circle, and the level of which is often below that of the common integuments. This circle, the skin of which is thinner and finer than that of the rest of the nipple, is termed the areola ( areola mamma.) § 2480. The texture of the mammæ is not the same in every part. Almost all its substance is composed of small reddish white grains (acini), which are distinguished very easily in females during the period of lactation. These grains are about the size of a millet seed. They are composed in turn of smaller vesicles, not rounded, but oblong, which are grooved and ranged in rays. They are united by cellular tissue and vessels. These grains do not exist toward the centre, in the areola, where we find only a fibrous and whitish substance, which is decomposed by maceration, into a tissue of canals, which are united by cellular substance. § 2481. These canals are the extremities of the milk-ducts (ductus galactophori, s. lactiferi). The latter arise by as many small roots as there are grains, and gradually unite in larger trunks, which finally terminate in the centre of the nipple, behind the areola by conical, dila- tâtions or sinuses. Tiie excretory passages of the mammary gland are larger than in any other conglomerate gland. The size of the trunks varies according as they receive a greater or less number of branches. Many are very small. The number of great branches which finally unite to give rise to one trunk, varies from four’ to twelve. The extent of the central sinus is also in direct ratio with the size of the. trunks. Sometimes these dilatations are from two to three lines broad ; but they are always short, compactly arranged at their internal extremity, and a little separated at their external. The internal extremity of each suddenly contracts into a very small canal, which passes in a straight line through the centre of the nipple to its summit, contracts a little, rarely enlarges in some part of its extent, and finally opens on the surface of the nipple by a very small orifice. All these small canals, which are about the breadth of a finger long, are united very intimately by mucous tissue. Only one canal comes from each dilatation. § 2482. The whole milk-passage,- which consequently includes the carrying portion, the dilatation, and the excretory canal, is formed by a soft, thin, and transparent membrane, similar to a mucous membrane. These passages are not exposed in most of their course. The trunks are often situated very deeply in the substance of the gland, and those even which proceed at first on its surface, especially those which come from the prolongations mentioned above, penetrate deeply. They are formed by the successive union of branches and twigs, which always diminish in caliber ; but they do not communicate by anastomosing branches. Nuck(l) and Yerheyen(2) have in fact described and figured very large anastomosing branches, situated in the areola, directly at the base of the nipple, which go from one milk-passage to another, and thus form a ring ; but no other person has found them, and we also have been unsuccessful, although we have carefully sought for them several times. This anastomosing circle is not only invisible, but also the injection pushed into one milk-passage never flows into another, which would be the case if the anastomoses really existed. The milk-passages are not provided with valves as several observers have stated. Farther, the existence of these valves is refuted by the facility with which injections enter through the nipple. Sometimes, however, we observe fluids, particularly mercury, injected through an opening in one milk-passage, return by another, but always under circumstances which prove the communication exists between the most minute ramifications of the passages. Probably the anastomoses, like the ducts themselves, do not dilate sufficiently to produce this result until toward the end of pregnancy, and during the period of lactation. But the researches of Meckel(3) on the mammae of females dying in OF THE MAMMARY GLANDS. parturition, demonstrate their existence as positively, as it refutes that of the anastomoses admitted by Nuck and Veiheyen. We have also obtained the same results under similar circumstances. § 2483. Notwithstanding these small anastomoses, the mammas is composed of as many distinct and separate glands as there are milk passages. This is demonstrated by injecting each canal with differently colored fluids, for the injections blend in no part, and the different glands can be detached and separated. § 2484. The number of the milk-passages, consequent^ also that of the conglomerate glands, varies even in the two mammæ of the same female. The old anatomists have reduced the number too much, as they estimated them only at six or seven ; Haller, Walter, Covolo, and ourselves, have never found less than fifteen. Our dissections, however, have convinced us that Walter was mistaken in saying that there are never more than fifteen, sometimes we have found more than twenty, as have also Haller and Covolo. Their greatest number is twenty-four, according to Covolo. These that are situated highest, and most on the outside, are, as Waiter justly remarks, very small and very narrow, which agrees with the less degree of thickness of the mammary gland at its upper part. § 2485. Besides the orifices of these milk-passages on the summit of the nipples, we find in the areola also, others which generally occupy the extremities of the tubercles ; these are arranged irregularly, and two or three of them sometimes unite in one. Several anatomists have considered these tubercles as simple sebaceous glands. Bidloo and Morgagni have sometimes seen coming from them a limpid liquid ; Morgagni, Winslow, and Covolo have also seen them supply a more or less thick milk in females, during lactation, and the last phenomenon has been observed also in males- by Morgagni. The quantity and the nature of the fluid coming from them, depends on the length of time which has elapsed between the repast and the time of nursing, so that several hours after the repast, or when the child has not nursed for a longtime, the milk is abundant, while in the opposite case, some drops of a brighter liquid slowly dribble out. These tubercles are entirely different from sebaceous glands. We find numerous sebaceous glands on the areola and the nipple, and they never rise above the surface like the tubercles, on which we often observe several. An attentive examination shows in several of these tubercles, one, and sometimes even four small excretory ducts, leading to small glands, which are precisely of the same nature as those we have mentioned, but which, however, are smaller ; they are situated directly under the skin of the areola, and are united with each other and with the body of the gland, by cellular tissue. Sometimes, in fact, but rarely, these small glands open into the portion of the integuments of the mammæ, which directly covers the circumference of the areola. They vary in number and size. There are generally from five to ten tubercles. Thus the small glands and the tubercles in which their excretory ducts terminate, are arranged in regard to the mammary gland, precisely in the same manner as the sublingual glands or the buccal and the labial glands, are in regard to the parotid and the submaxillary, and they cannot, at least in our opinion, be regarded as anomalies, as Hildebrandt thinks them.(l) § 2486. The mammary gland is situated in a more or less abundant adipose tissue, which does not form a continuous layer as in every other part, for it enters between the depressions which we have mentioned above, and even contrary to what occurs in the other glands, it penetrates deeply into the substance of the organ, while there is none at its base. We find no fat in the nipple nor behind the areola ; this fat is more firm and yellowish than in most of the other regions of the body. The mucous tissue which contains it, also penetrates into all the spaces between the different glands. It condenses on the surface of the organ in a special sheath, nearly similar to those which surround the muscles. Haller asserls(2) that he has frequently seen milk-passages arise from the fat, which afterwards penetrated into it. Covolo and ourselves have seen nothing like this. We have every reason to think that Haller is mistaken, and that his error must be attributed to the existence of the prolongations mentioned above. § 2487. The vessels of the mammae arise from the external thoracic vessels. Their nerves come from the third and fourth cervical, and from the five or six superior dorsal nerves. § 2488. The function of the mammary gland is to secrete the milk. In the normal state this secretion does not begin until toward the end of gestation. Its history will be more in place after that of the phenomena produced by coition. § 2489. Until the sixteenth week there is no trace of the genital organs. When they appear they are formed precisely after the same type in all fetuses ; their form, volume, and situation are the same, and there is consequently no distinction of sex. The internal genital organs are formed ; 1st. Of two very elongated and narrow parts, oblique from without inward und from above downward, situated very high out of the pelvis, and which afterward become either the te'sticles or ovaries. 2d. Of two canals which are not much narrower, but which are longer and thicker, proceed beyond them above, and descend on their outer side. They produce either the tubes, or the epidydimi and the excretory organs of the semen, and unite out of the pelvis in a common median duct, which becomes either the uterus and vagina, or the prostate gland, seminal vesicle, and posterior part of the urethra. 3d. Of a considerable triangular body, a little enlarged at its anterior extremity, situated first at the- lower part of the anterior wall of the abdomen, and which afterward hangs loosely forward. There is soon developed on each side of this last body a fold of skin, which is directed from before backward. These two folds are not united posteriorly. They change into the scrotum, or the external labia. § 2490. Home,(l) Autenrieth,(2) and Ackermann(3) had already admitted this primitive identity of the genital organs in all individuals, although they indicated perhaps less exactly and precisely the characters of the primitive form, and the manner in which the differences occur. As all the fetuses at this period, which we have compared and they are at least fifteen, present exactly the formation described, it is more correct to consider, as is generally done, the raphe of the scrotum and penis as a mark of the separation primitively existing, and which gradually disappears by the closing of the fissure from behind forward, than to regard it, with Autenrieth, as proving a tendency to this separation which really occurs only in the female. Thus we have already said for a long time, reasoning from the facts observed by us, that the genital organs are formed after the same type, particularly after that of the female. (4) We . have already established from observation that their character is still more similar to that of the female in all fetuses, (5) and Tiedemann has confirmed this result, describing very exactly several fetuses very near the moment of then formation.(6) (4) Abhandlungen aus der menschlichen und vergleichenden Anatomie , 1806, vol. ii. We have there described six fetuses of this age. — Beytruge zur vergleichenden Anatomie, 1808, vol. i., part i., no. 5. We have there described twelve fetuses of this age. These phenomena are curious in two respects : 1st. There are generally no genital organs in most of the lower animals, or at least those which exist correspond to the genital organs of the female in those where there are two sexes, so that in this respect also the same law prevails in the development of the fetus and that of the aminal series. Farther the great size of the clitoris, the -smallness of the uterus, and perhaps also a real connection between the ovaries and the Fallopian tubes : and secondly, the situation of the testicles in the abdomen, establish still longer between the two sexes a similarity which afterward does not exist. From the third month of pregnancy, however, the ovaries are always smaller than the testicles ; they are situated more horizontally, and the penis differs from the clitoris, as the fissure has disappeared from its surface. 1. GENITAL ORGANS OF THE FEMALE. § 2491. The development of the genital organs of the female differs particularly from that of the genital organs of the male, in the less number of successive periods through which it passes. § 2492. At first the ovaries/ 1) proportionally speaking, and particularly in regard to the other genital organs, are much larger than they are subsequently. They form for a long time most of these organs, although when the difference of sex is more evident, they are proportionally smaller than the testicles, and this difference even is one of their principal distinctive characters. At about the middle of the third month of fetal existence, and when the embryo is two inches long, they are hardly a line and one quarter in length, less than half a line high, and a little less than one third of a line thick. In the full-grown fetus they weigh between five and ten grains. They are situated almost horizontally far above the small pelvis, but from their horizontal direction their upper or external extremities do not rise as high as the testicles in the male fetuses of the same age, so that they are very far from touching the kidneys. Their internal extremities, on the contrary, are so near each other that only the rectum exists between them, which is at this time very narrow, so that the intestine does not completely separate them. Their form is very elongated, narrow, and prismatic ; ihey become rounded only at puberty, and they are then thicker in proportion to their length. Their capsule is very thin, not only in the full-grown fetus, but also during all the early years of life. Their tissue is more simple until the middle of the first year of existence. In this respect we have as yet been unable to discover any trace of the vesicles of Graaf before the age of six months, when these vesicles form, and they arè then proportionally very large. In the latter half of the existence of the female the ovaries begin to grow harder and to waste. They lose their smoothness, and their surface appears more or less uneven, because the depressions observed in it are changed into considerable cavities. This effect depends principally on the disappearance of the parenchyma ; but the vesicles also change at the same time ; they diminish, their membranes become thicker, and finally their cavity disappears, and they are converted into yellowish or blackish, or often into fibrocartilaginous or osseous bodies. The ovaries wasta so much in females advanced in life that they sometimes disappear. entirely, and the place they occupy is indicated only by the vessels. Frequently then they weigh only twenty grains. § 2493. According to several writers, as, for instance, Malpighi, (1) Vallisneri,(2) Santorini, (3) Bertrandi,(4) Brugnone,(5) and Buffon,(6) the formation of the yellow bodies ( corpora lutea ) belongs also to the history of the development of the ovaries, because they have been found not only in virgins, but in the young females of animals. But it is not well proved that these bodies have the same origin and the- same use as the common yellow bodies ; and it is extremely probable that their formation has been preceded by an increase in the activity of the genital organs, arising from some cause. We think it more proper to refer the examination of them to the chapter on the changes produced in the genital parts by conception. II. TUBES, UTERUS, AND VAGINA. § 2494. The Fallopian tubes, the uterus, and the vagina, form at first only a single canal, cleft at its upper part, which is uniformly broad, and which extends uninterruptedly from the abdominal extremity of the tubes to the external orifice of the vagina. longer than they are subsequently. They descend at first very obliquely from without inward on the outside of the ovaries, to which they are directly united, but extend much beyond their upper extremity. Until the third month they are united at an acute angle at their lower and inner extremities in a small and median perpendicular mass, which is at first very narrow, but which gradually becomes a little wider, and represents the uterus. They are not tortuous until the fourth month. (1) At five months only they begin to exhibit curves, which are at first very indistinct, and gradually enlarge, so that at eight months and at birth they are more tortuous than in the adult : an arrangement which they preserve also during the first years of life. They seem at first to terminate in a cul-de-sac and by an enlargement. Their abdominal extremity seems to open at the fourth month, but the fimbriated ends are not developed till afterward. Their cavity is always much larger proportionally the younger the fetus is, and it is always found without difficulty whenever it is sought for. (2) Bettveen the tubes and the ovaries in the fold of the peritoneum extremely curious vessels(3) exist, not only in the embryo and the fetus, but also during the first years of life ; these cannot be injected through the tubes nor through the ovary, so that we cannot consider them as establishing a communication between the cavity of the former and the substance of the latter ; they are so similar in their number, situation, and form, to the vasa deferentia of man, that we must consider them at least as tending to the formation of these passages and the epidydimis. The primitive form of the abdominal extremity of the tube, however, allows us to conjecture, and with some probability, that they communicate first with the ovarjq but that the communication is probably closed when the abdominal extremity of the tube opens, and consequently when a new passage forms. B. UTERUS. § 2496. The uterus is at first, and usually even until the end of the third month at least, much broader, and has two horns. " The horns are as much longer and their angle of union is more acute the younger (1) The general opinion then that the tubes are always tortuous in the fetus is not exactly correct. Their primitive straightness is very important, on account of the analogy it establishes, first between them and the intestinal canal during the early periods of existence, and also between them and the oviducts of several animals. the fetus is. But when this angle entirely disappears, the uterus seems to have two horns. At first it is equally broad in every part, and perfectly smooth ; there is no prominence either on the outside or on the inside which separates it from the vagina. It begins to enlarge at its upper extremity about the end of the fourth month. This phenomenon depends on the disappearance of the horns which existed at first, and which are replaced by a single cavity. But this upper part is much smaller the younger the fetus is, whence the neck is larger than the body in the same proportion. The body gradually increases, so that about the period of puberty the uterus loses its almost cylindrical form, and becomes pyriform. The length of the body is only one fourth of that of the whole organ in the full-grown fetus ; it is only one third at thirteeen years old, and does not form one half till after puberty. At the same time transverse and slightly oblique wrinkles are developed on the anterior and the posterior faces ; these converge upwards towards the orifices of the tubes, but are very compact at the lower part where they begin to appear, and gradually extend over the whole of the uterus. There forms also imperceptibly on the two faces of the organ an elongated eminence which passes through its whole length, and toward which the wrinkles on each side converge from above downward. These wrinkles enlarge very much. They render all the inner face of the uterus very uneven, not only in the full-grown fetus, but also during the early period of life. They however gradually disappear in the body, and at the age of five years its inner face is entirely smooth. The external orifice of the uterus appears at first as a slightly perceptible prominence of the organ in the vagina ; but this prominence gradually increases, so that in the latter periods of fetal existence, the vaginal portion of the uterus is proportionally much larger than subsequently. At seven and eight months less than in the fullgrown fetus, and during the first months after birth, all this portion of the organ is very uneven, and also on its external face, presents longitudinal wrinkles, terminated by sharp uneven edges, which are deeply fissured, the grooves of which often occupy all the vaginal portion. This prominence afterwards shortens, becomes smooth externally, takes the form of a glove, and the uterine orifice then appears as a simple and smooth transverse fissure. . The parietes of the uterus are as much thinner in proportion to the 'cavity, the younger the fetus is. At first they are equally thick in every part ; but at five months they become much thicker in the neck than at the upper part. Gradually between the age of five and six years, the thickness again becomes uniform in every part, and preserves its character till puberty, at which time the body is much thicker than the neck. It is the body principally which grows in the adult, and the uterus then assumes a triangular form. In females advanced in age, it becomes irregularly rounded, which does not depend on previous pregnancies, since the same changes are observed in old unmarried females. At the same time it diminishes in those females who have lived in celibacy. The consistence and the color of the uterus in old age, resemble those of infancy. At these two periods the organ is hard and white, while in the prime of life it is soft and red. In the fetus of three or four months, the uterus is situated almost entirely out of the small pelvis, and it extends much beyond in the fullgrown fetus. After the age of fifteen years, it is entirely situated in the pelvis, at the base of which it is found in old females. siderable periodical differences. At the period of puberty, when the female has the power of conception, there is every month a discharge of blood and serum from the genital organs, which continues some days, and is termed menstruation ( menstruatio , s. menses ), from its occurring periodically. This discharge disappears with the susceptibility for conception, usually between the fortieth and the fiftieth year. It is not a character belonging exclusively to women.(l) This discharge proceeds from the whole inner face of the uterus. This conjecture is strengthened by chemical analysis. In fact, Lavagna(3) has found in it no fibrin. But Saissy and Mayer(4) have proved that the venous blood contains less fibrin, and consequently less azote than the arterial blood. Menstruation essentially consists undoubtedly in an increase of the vitality of the genital organs of the female, resembling inflammation, and of which hemorrhage is the crisis. This is demonstrated by the irritation in' these organs before the period of menstruation, the greater propensity of the female at that time for coition, and the greater facility with which she conceives. We may also consider it as an attempt to form a new organism. In fact, the changes in the uterus at this period, resemble those observed in it after conception. On the other hand, according to the observations of Denman, Brandis, and Joerg, the menstrual blood is not unfrequently attended with membranous productions, similar to the deciduous membrane which is developed when the female has conceived. Finally, menstruation may carry off from the body generally, and the genital organs particularly, probably not injurious substances, but at least superfluous blood, for while the female is disposed to conceive, the blood always collects in these organs from one menstruating period to another, to form there a new organism, and during pregnancy and lactation it is employed in other formations. § 2498. At first the vagina is not broader than the uterus, and is entirely smooth like it. It begins to be uneven at about the same time. First, at about the fifth month a longitudinal elevation appears on each anterior and posterior face. This elevation afterwards presents very many large transverse folds arranged very compactl}7. These folds are united by others, which are oblique, and are distributed on the whole circumference of the vagina, so as to render its surface much more uneven and reticulated, as they themselves present numerous fissures and folds. This is the appearance of the vagina at seven and eight months. But the folds gradually dimmish ; they are less evident in the full-grown fetus ; they afterwards gradually disappear, become less prominent, more closely united, farther from each other, so that at the period of puberty, even before coition, the vagina is much smoother, and is only corrugated at its lower extremity on its anterior and posterior faces, in the first more than in the second. and eighth month. It is always proportionally longer in the fetus than subsequently. It is always more than two inches long in the fetus of eight months, and in the child at birth, while in the adult female its length is seldom more than four inches. This arrangement depends at least in part on the higher situation of the uterus, but not entirely on this, as the vagina is not narrower in the same proportion. § 2499. The vagina is much narrower at its lower part than in other places. We discover no trace of the hymen before the middle of gestation. At this time it begins to appear on each side in the form of a thin and narrow prominence, which is directed from behind forward, so that a longitudinal fissure exists in the centre. This prominence is at first directed downward, and is equally broad in every part; but it gradually becomes broader backward, so as to form a semicircular fold, or rather a rounded and oblong septum, which presents an opening at its anterior extremity. The hymen preserves this form until it is destroyed. The inequalities of the vagina are also continuous in the fetus, on it, and on the orifice of the urethra, from whence they descend on the clitoris, and the inner face of the internal labia. proportionally very large, and the more so the younger the fetus is. At the commencement of the third month, when the latter is at most but two inches long, its length is about one line, and it is half a line thick. In fact, it soon loses these large proportions, but it remains considerable during the whole of gestation, so that a slight, examination might easily deceive in regard to the sex of the child, which is more probable, because the scrotum is then very small, and the testicles are situated in the abdomen ; but the clitoris is always turned forward and downward, and never looks toward the umbilicus.(l) The glans is not entirely exposed until the fourth month ; it forms a rounded prominence, and is distinctly separated from the rest of the clitoris. When this period has elapsed, the prepuce grows rapidly, and entirely envelops it. The posterior part of the clitoris is composed of the internal labia and the prepuce ; the internal labia are then very much developed during the early periods ;(2) we cannot distinguish them from the prepuce, with which they are directly continuous. As the prepuce forms and extends on the glans, a line of demarkation gradually forms between it and the internal labia, the edge of which was at first straight, becomes rounded ; at the same time they evidently divide at their anterior part, and on each side, into two branches, the one small and internal, which goes to the glans, the other external, going to the prepuce. Previously there was no trace of these two branches. p. 46), the nymphæ are very imperfect, and hardly perceptible at three and four months ; observation disproves this assertion. The fact is, that the internal labia are not so large in proportion to the very large clitoris, as they are afterward, but they are very large in respect to the genital organs and the whole body, so that they cannot be mistaken for what they really are not. § 2501. The external labia are at first, at three months, small, rounded, semicircular sacs, convex outward, much thicker anteriorly than posteriorly, and nearer each other at their anterior than at their posterior extremities, and separated forward by the large clitoris, which projects much beyond them. They gradually enlarge, approach each other, as the clitoris does not increase in the same proportion, become more elevated and thinner, and thus their edge becomes sharper. They never, however, cover the clitoris and the nymphæ entirely, during the early periods of existence ; first, because these parts are always considerably large; second, because they themselves are but slightly developed. § 2502. The genital organs in the male during their development, pass through several periods, which are very important in a physiological, pathological, and surgical point of view. The differences they present, relate to their situation, form, and size. the most important parts, and appear first. They form not in the scrotum, but in the abdomen, and particularly in the peritoneal cavity, and has the same relation to it as have all the other organs enveloped by this membrane. About the middle of the third month their upper extremity still touches the lower extremities of the kidneys. At this time they are situated obliquely from above downward, and from without inward, (1) Haller, De lierniis congenilis, programma ad dissertationem tSteding, Gottingen, 1749.' — Pott, Oïl ruptures, 1756, p. 13.— Camper, in Verhandetingen vanhet Harlcmsche genootschap, 1761, vol. vi. part i. — J. Hunter and G. Hunter, Medical commentaries , London, 1762, p. 1. p. 75. — Id., in Observations on certain parts of the animal economy, vol. i. — Arnaud,, in Mémoires de chirurgie, vol. i. no. i. London, 1768. — Lobstein, De herniâ congenita, in qua intestinum in contactu testis est, Strasburg, 1771.— J. F. Meckel, De morbo hernioso congenito singulari, Berlin, 1772. — Girardi, in Santorini, Septem, tab., . Parma, 1775, p. 184-202. — J. B. Palletta, Nova gubernaculi testis Hunteriani et tunicœ vaginalis anatomica descriptio, Milan, 1777. — H. A. Wrisberg, Observationes anatomicoe de testiculorum ex abdomine in scrotum descensu, Gottingen, 1779. — Vicq-d’Azyr, in Mém. de Paris, 1780, p. 494507. — -J. Brugnone, De testium in fcetu positu, dé eorum in scrotum descensu, de tunicarum quibus hic continentur, numéro et origine, Turin, 1785. — Tumiati, loc. cil., p. 541. — J. F. Lobstein, Recherches et observations anatomico-physiologiques sur la position des testicules dans le bas-ventre du fœtus et leur descente dans le scrotum ; in Schweighæuser, Archives de V art des accouchemens, Strasburg, 1801, vol. i. p. 269. — B. G. Seiler, Observationes nonnullœ de testiculorum ex abdomine in scrotum descensu et partium genitalium anomaliis, Leipsic, 1817. occupy all the inner face of the ossa ilia. They are very large, since in the fetus of this age, which is scarcely more than two inches long, they are two lines in length and one line thick. They are rounded and oblong, convex anteriorly and concave posteriorly, and rest on a very broad fold of the peritoneum, which first covers the epidydimis, then goes on the posterior and concave face of the testicle, leaving between them a great space, arises from the posterior face of this gland, but is by no means as high as that, and is very similar to the epiploon. They adhere to this fold so slightly, that their situation is easily changed, and particularly carried outward or inward. The epidydimis rises no higher than the testicle, descends at its side from before backward, and a little from within outward, and is continuous at its'lower extremity with the vas deferens, which descends into the small pelvis behind the peritoneum. At the place where this continuation occurs, the whole mass, but the epidydimis and vas deferens particularly, rest directly on a short, very fine, rounded cord, which arises from a depression of the lower wall of the peritoneum, at about-the centre of the crural arch, which is also covered by the peritoneal membrane, but less loosely than the testicle, because the fold is shorter in the point which corresponds to it. This cord is infinitely thinner than the testicle and the epidydimis. diminishes. At four months, when the fetus is four inches long from the vertex to the coccyx, their length is scarcely two lines and a half, and their thickness at most but one line. The epidydimis is then larger in proportion to the testicle, than before or afterward. The testicles are situated a little lower, but very little however, but are more remote from the kidneys, being at least four lines from them, because the ossa ilia are much larger. The vas deferens is then reflected a little from below upward on leaving the lower extremity of the epidydimis, so that it describes an arch before descending into the pelvis. The gubernaculum is much larger, and it arises from the region of the inguinal ring, although the peritoneum is not perforated in this place ; but is only reflected on itself from below upward, and envelops a mucous mass to which we must attribute the thickness and the more round form of the gubernaculum. At five months, the testicles are not longer than in the preceding month, but they are about half a line thicker, so that they appear a little rounder than they were then. They have not descended lower, or at least but very little, and they are still more than a line distant from the lower wall of the peritoneum. The gubernaculum, which is then evidently triangular and the summit of which is much thinner than the inguinal ring and goes downward, while its base looks upward, ascends obliquely from within outward. It begins a little below the inguinal ring, at the upper part of the scrotum, by some distinct fibres, passes through the ring, then receives some fibres from the obliquus internus and transversalis abdominis muscles, behind which it passes, then ascends on the iliacus muscle, and rises directly to the lower extremity of the epidydimis. At its lower part, between the inguinal ring and the place where it appears in the abdominal cavity, we discover before it a prolongation of the peritoneum {processus peritonei) which terminates in the ring in a cul-de-sac. This prolongation also descends obliquely from without inward. Its upper orifice is much broader than the lower, and than the gubernacuium which passes through it. The epidydimis is evidently tortuous at its lower part, and the vas deferens is slightly so at its origin. At six months the testicles are still situated in the same place. At this time they are only four lines long, and one and a half thick, so that they are proportionally oblong, and almost straight. The epidydimis rises a little above the surface of the glans, and like the vas deferens, it is more distinctly curved than in the preceding month. The same is true of the gubernacuium and the prolongation of the peritoneum. Sometimes we may pass air into the lower part of the gubernacuium, and it is sufficient in certain cases to cut it across to perceive that it is hollow. Thus, there has hitherto existed a canal, terminated in a cul-de-sac, a prolongation of the peritoneum, which descends from about the centre of the lower tendon of the obliquus abdominis externus muscle, between this muscle and the lower edge of the two broad internal abdominal muscles, and behind which proceeds a prolongation of mucous tissue, which is generally solid, and to which are added some fleshy fibres from the two broad internal abdominal muscles. But the testicle is still loose in the cavity of the peritoneum, where it rests on the upper extremity of the gubernacuium. At seven months we generally find it directly on the upper extremity of the canal, or more or less within it, so that frequently it does not project at all beyond -it, or only in a very small part of its upper extremity. It is usually situated behind the lower edge of the obliquus abdominis extemus muscle. The prolongation of the peritoneum then extends downward, to just above the inguinal ring. It seems composed of two lajrnrs, the internal of which is thinner, and is continuous with the peritoneum, while the external is a mucous tissue, and is continuous with the sheath of the obliquus abdominis externus muscle, in which are distributed the fleshy fibres coming from the obliquus internus abdominis and the transversalis muscles. The lower part of the prolongation of the peritoneum is filled above by the lower extremity of the epidydimis, and by the commencement of the vas deferens ; these rest on a small mass of mucous substance, which rises from the lower extremity of the prolongation of the peritoneum, and they are united with it posteriorly by a fold, which is detached from the posterior wall of this prolongation. At eight months, the testicle itself usually passes through the inguinal ring, and gradually, until the end of the ninth month, arrives at the bottom of the sacrum, so that its situation is normal about the period of birth. The prolongation of the peritoneum is then considerably elongated ; it is open its whole extent, excepting only its lower extremity, which terminates in a cul-de-sac, and it communicates freely by its upper with the proper peritoneal cavity. After the testicle has descended entirely to the bottom of the peritoneal’prolongation and of the scrotum, its cavity still continues to communicate with that of the peritoneum for a greater or less length of time, but not more than a few weeks when the development is perfectly normal. But the canal of union gradually contracts at its centre, a little nearer the top than the bottom, so that usually that portion of the prolongation of the peritoneum which surrounds the testicle, begins to be obliterated near the inguinal ring. The upper portion of the canal from the inguinal ring to the centre of the crural arch, or to the place where the vas deferens joins the spermatic vessels, remains open for a considerable time ; but when the child is regularly developed, it is also obliterated during the first months after birth, so that it is finally only indicated by a slight depression, which by no means always exists. The central portion of the canal of communication also is perfectly obliterated as high as the upper extremity of the testicle, and entirely disappears in most cases. At least we have rarely been able to see any traces of it, although we have made the most careful examinations on this subject. We cannot then agree with Brugnone and Scarpa, that we always find in the adult a special cord, composed of cellular tissue, termed by them the bridle {habenula), which they consider as the remains of a canal of communication, and the cavity of which they assert can always be demonstrated by maceration. Thus the canal of union is first obliterated, and then disappears. Adhesion in it results from its serous nature, and like its disappearance, it is perhaps favored by the pressure of the testicle upon it. § 2504. Farther, these changes in the situation of the testicles do not occur at the same period, and uniformly on the two sides ; one of the two organs usually comes into the scrotum long before the other. The anomalies in the progress of this phenomenon are as follow : 1st. The early descent of the testicles. This case is rare : Wrisberg has found the testicles in the scrotum at four and five months, and has also remarked that the canal of communication was then obliterated.(l) 2d. A suspension of development, from whence several periods are retarded, or even never supervene. This case is much more common than the preceding. The greatest anomaly is where one testicle or we may think one or both of these organs are deficient. In this case the testicles are arranged in regard to their envelops precisely in the same manner as in the fetus, as they are entirely exposed, and are provided with a gubernaculum. The least anomaly is where the peritoneal prolongation is imperfectly obliterated. When this last anomaly exists in the greatest degree, the canal remains entirely open, so that the testicle is inclosed in the same cavity as the other abdominal viscera, although its position is otherwise changed. When the anomaly is less, sometimes and most frequently, only the upper part of the peritoneum is open, which extends between the inguinal ring and the obliquus abdominis internus muscle ; sometimes and more rarely the lower part of the prolongation does not adhere, so that not only the layer which surrounds the testicle, and which becomes the external layer of its proper vaginal tunic, forms an oblong and rounded cavity, but also we see arise from the upper extremity of this sac a canal varying in length, which marks the old canal of communication ; sometimes finally and more unfrequently, the obliteration occurs regularly at the two extremities of the canal of union, but the central part of this latter continues in a greater or less extent. The fold of the peritoneum, which is attached to the latter, is continuous with the posterior wall of the peritoneum, and at this period the testicle, like the other abdominal viscera, is not inclosed in a proper capsule, with which this serous fold is continuous, as are the lungs or the heart. The other envelops which cover it in the scrotum are developed at the expense of the gubernaculum, and the prolongation of the peritoneum. The peritoneum becomes the external and loose layer of the proper vaginal tunic of the testicle, with which, when the testicle has descended, the internal layer is continuous, precisely in the same manner as it was previously connected with the external wall of the peritoneum. formed from the cellular tissue within the gubernaculum. At this period also the fibres coming from the two internal muscles of the abdomen, which were at first ascending, go outward, and form the cremaster muscle. The cellular tunic or the dartos already existed in the scrotum, and the testicle entered it on descending. upper extremity becomes the lower ; hence the epidydimis which is attached to it, and with it the testicle, are necessarily drawn from above downward. The prolongation of the peritoneum also emerges in the same manner outward, and independent of this inversion, since it already exists before the testicle descends, and it supervenes also in hernias which are caused simply by the spontaneous prolapsus of the peritoneum, without any other mechanical change. The descent of the testicle is generally explained entirely in a mechanical manner, and attributed to the compression produced by the motions of respiration upon the abdominal viscera,(l) or to the weight of the testicle, (2) or to the greater flow of blood into its vessels, (3) or finally to the contraction and inversion or to the reversion of the gubernaculum.(4) The first opinion is not correct, since when the formation is normal the testicles usually descend in the scrotum long before birth, and they are often found in the abdominal cavity long after parturition, when the formation is abnormal. The second is refuted by the habitual situation of the fetus, as the testicle would ascend against its specific gravity. The third is inadmissible, because if true the testicles should be situated as much lower the younger the fetus is, since then they are proportionally the largest. The contraction of the gubernaculum doubtless does not cause the gliding of the testicle to the inguinal ring ; but it does not contribute to its farther progress in the scrotum, for instead of favoring its motion in this direction it would rather contribute to raise it. "We cannot, however, deny that it assists very much to the displacement of the organ, and this is proved positively by the great development of the muscular fibres of the gubernaculum in those animals where the testicles possess alternate motions, whence they enter and leave the cavity of the abdomen alternately. If sometimes the testicles do not descend, although the gubernaculum exists, we must not conclude that this latter takes no part in the phenomenon, since other circumstances may prevent its action, or at least may produce the effects it generally causes. Farther, its contraction is only one mode of causing the displacement of the testicle, and the cause of this displacement is unknown to us. § 2506. When man has passed the period of his virility, the testicles diminish a little, at least frequently ; but they rarely waste as much as the ovaries, and the power' of impregnation continues longer in the male than that of conception in the female. II. PENIS. § 2508. About the middle of the third month the glans is not yet covered by the prepuce, and a deep groove separates it posteriorly from the proper penis, which is larger than it. Its anterior extremity is imperforate ; we only perceive a whitish spot at the place where the urethra afterwards opens. But we always observe at this period a longitudinal fissure, which sometimes exists posteriorly on the small portion of the lower face of the glans and which constantly occupies the anterior extremity of the lower face of the penis situated directly next to it. Thus the urethra does not extend as far forward as when the development is completed, and farther its anterior part presents a fissure below. This fissure, however, by no means extends to the posterior extremity of the penis. penis forward, and is entirely closed. At four months, the appearance of the scrotum is not changed, but the form of the penis is altered. The glans is a little larger proportionally, is covered by the prepuce at its posterior and inferior part so that only the lower part of its anterior side is exposed, and we remark at the lower part of its anterior surface a longitudinal fissure, which is the opening of the urethra. Next comes a state directly opposite, which continues during the whole of gestation. The prepuce is very much enlarged, covers the whole glans, and presents only a very narrow opening ; it is adapted so intimately to the surface of this part that it cannot be drawn backward. § 2509. The mammæ are already apparent at the third month of pregnancy, at which period the nipple is scarcely perceptible, but presents a very' broad opening. It is worthy of remark that they generally contain during the latter period of gestation, and in the fetus at birth, a lactescent liquid, of which there is often a considerable quantity. Until the period of puberty they present no marked differences in the two sexes ; but at this time they enlarge more or less in the female. They are more or less hard and solid. As age advances they diminish, which occurs sooner when their action has been exhausted by frequent lactations. Even where their mass does not seem diminished, and they are even enlarged, the substance of the gland is, however, replaced by fat. The internal labia are very long in certain Ethiopian races, among others that of the Boschismans, as we have already mentioned. This is the origin of the apron of the Hottentots, which the recent observations of Somerville and Cuvier have demonstrated not to be a new organ. COMPARISON OF THE MALE AND FEMALE GENITAL ORGANS. § 2511. We have already mentioned several times that the genital organs of the two sexes are formed primitively in the same model, and that they should be considered only as modifications of the same fundamental type. In fact it is easy to demonstrate that all the parts which unite to form this system exist equally in both sexes, and differ only in size, situation, and structure. • The analogy appears much greater the younger the fetus is, and that it is founded on the nature of things is proved by the fact that they are originally of the same sex. The Fallopian tubes are evidently analogous to the vasa deferentia. We however have reason to think they originally communicate with the ovaries by straight canals, and by a kind of epidydimis similar to that which exists in the male between the vas deferens and the testicle. The seminal vesicles and the prostate gland undoubtedly correspond to the uterus in respect to situation and connection, with the vasa deferentia, and the Fallopian tubes ; the uterus however is larger and more completely developed, and the orifices of the seminal canals are more remote from each other. The penis and clitoris are similar in essential respects as to situation and structure. They differ only in their respective size, and because the urethra does not extend under the clitoris. This difference however disappears, when we consider the imperfect development of the clitoris is compensated by that of the vagina or nymphæ, which must consequently be regarded as the penis and urethra of the male, the two lateral halves of which are separated, and which are turned inward instead of outward. then the urethra does not extend to the anterior extremity of the penis. We explain in the same manner the difference between the bulbocavernosi and the constrictor vaginæ muscles. These two muscles correspond ; the two halves of the second, however, are united only on the median line. before the period of puberty. Thus the analogy of the genital organs of the female is found in the other sex. The history of hermaphrodites will demonstrate that the deviations of formation contribute still more to efface the differences between the two series of organs, and these anomalies produce between them so great a resemblance, that it is often very difficult to determine to what sex the individual really belongs. 3. GENERAL ANOMALIES § 2512. The genital organs present some anomalies common to the two sexes, and others peculiar to one only, a remark which applies also to deviations of formation and alterations of texture. In this respect we must remark, that the corresponding sections of the genital organs usually participate in the same anomalies, or at least present those which are very analogous. the type of the fetus. Such are : a. The entire or partial absence of the genital organs. The first anomaly causes the total absence of sex, although the rest of the body sometimes indicates clearly to what sex the individual would have belonged if the genital organs had been developed. preceding anomaly, is however a rare phenomenon. (I) Consult, 1st. On the diseases of the genital organs generally : Vercelloni, De pudendorum morbis, Leyden, 1725. — 2d. On those of the organs of the female in particular : J. G. Walter, lieber die Geburtstlieile des weiblichen Geschlechts , Berlin, 1776. — Justi, Diss. cxhibens observationum sericm circa genitalia muliebria, Marburg, 1798. — Thamm, Diss. de genitalium sexus sequioris varietatibus , Halle, 1799. — 3d. On those of the external genital organs of the female : Louis, De partium externarum generationi inservientium in mulicribus naturali , viiiosâ et morbosa dispositions, Baris, 1764. — 4th. On those of the ovaries ; Kruger, PatholOgia ovariorum muliebrium, Gottingen, 1782. — Motz, De structura, usu et morbis ovariorum, Giessen, 1789.— 5th. On those of the Fallopian tubes : Leonhardi, Quœdam de tubarüm uterinarum morbis, Wittemberg, 1808. — 6th. On those of the matrix and of the vagina : A. Vater, De morbis uteri, Wittemberg, 1709. — Haller, De morbis uteri, Gottingen, 1753. — Schwarz, De uteri degeneraiione , Jena, 1792. — Clarke, Diseases of females, London, 1814. — 7th. On the anomalies of the hymen: G. Tolberg, De varietate hymenum, Halle, 1791. — Osiander, loc. cit. — 8th. On the diseases of the genital organs of the male in general: G. Wadd, Cases of diseased bladder and testicle , London, 1815. — 9th. On those of the testicle : Henrel, Diss . de morbis scroti, Strasburg, 1723. — J. Warner, Account of the testicles and the diseases to which they are liable, London, 1774.-10. On those of the prostate gland : E. Home, Observations pratiques et pathologiques sur le traitement des maladies de la glande prostate, Paris, 1820. — llth. — Thaut, De virgœ virilis statu sano et morbosa , Wurzburg, 1808. — C. Bell, Engravings of specimens of morbid parts, London, 1813. — J. Howship, Practical observations on the diseases of the urinary organs , London, 1816. 4th. It is less rare to find tire characters of both sexes blended in the same individual, one or several parts of whom are formed after the type of one sex, and the rest of the body after that of the other sex. This anomaly essentially constitutes hermaphrodism. 5th. Alterations in texture. They are seen most frequently, and are most developed, in the genital organs. Not a single new formation but has been seen in some part of the genital apparatus, which undoubtedly depends on the energy of the formative power being greater in this than in any other of the organic systems I. HERMAPHRODISM. § 2513. Hermaphrodism, (\ ) which constitutes the second class of deviations of formation in regard to quality, is indicated in the formation of the genital organs, of which alone we shall treat here, by the formation of one part of the sexual system, after a type contrary to that of the rest or of the whole body, that is, with or without an increase in the organs of generation. 5 th. By the different degrees of its imperforation. 6th. By the division of the scrotum, and the existence between the penis and the anus of a canal similar to the vagina, varying in its dimensions, which leads to the prostate gland, and which is often attended by one of the three preceding anomalies. 1st. By the hernia of the ovaries through the inguinal ring. — Burdach, Die Metamorphose der Geschlechter, oder Entwichlung der Bildungsstufen durch welche beide Geschlechter in eidander ubergehen ; in his Analomische Xj ntersuchungen, part i. 1814. — All the works which have appeared before on the same subject are mentioned there. — Seiler, Observationes J nonnullœ de tcsticulorum ex abdomine in scrotum descensu et partium genitalium anomalis , Leipsic, 1787. — J. Feiler, Ueber angeborne menschliche Missbildungen , im allgemeinen, und Hermaphroditen insbesondere , Leipsic, 1820. 7th. By the imperfect development of the mammae. All these anomalies do not necessarily coexist in the same organism: but hermaphiodism, and the equivocal character of the sex which depends on them, are more marked, the greater the number of those existing. Generally only one or some of the different parts of the genital apparatus are constructed after different types, and the synonymous parts of the two sides correspond. It is much more rare to find an hermaphrodism so perfect that each of the two lateral faces present all the characters of a different sex. and perfect analogies with animals. Hitherto, however, not a single instance of human hermaphrodism is known where the two sexes were so completely united that it was possible either alone or with other individuals to procreate both as a male and female. All imaginary reasonings, however, cannot demonstrate the impossibility of such a formation, as it exists in many animals, as hermaphrodites have been seen which were very nearly in this state, as several phenomena seem even to prove that a perfect male organism sometimes possesses the creative power, independent of the other sex, and we cannot to a certain extent absolutely refuse this power to the female. a. Ovaries and tubes. § 2514. Among the primitive deviations of formation in the ovaries and their excretory ducts, the Fallopian tubes, we remark the following, which arise mostly from suspended development : constitutes a consecutive deviation of formation. Another anomaly, which is generally congenital, but more rare, consists in the hernia of the ovaries and Fallopian tubes through the inguinal ring, in which case they resemble the testicles. When the anomaly exists in the greatest degree possible, the uterus is divided at its upper part into two horns, and also divided into two halves by a septum at its lower part. Next come two nearly equal degrees : sometimes the body of the organ is extended into two horns, and the neck is single ; sometimes the form of the uterus is normal externally, but its cavity is divided into two halves at its lower part by a septum. Next come two other degrees ; in one a groove more or less deep at the bottom of the organ makes it appear imperfectly double horned, in the other, it is single externally, while its body is divided into two portions. uterus is only more elongated. These different degrees in the anomaly present very remarkable resemblances with the formations seen in animals, and with animals situated as much lower in the scale as the deviation is greater. Primitive deviations of formation consisting in an excess of the formative power, are hardly known. The term double uterus (3) has been wrongly applied to those which present several of the anomalies mentioned by us. (3) F. Tiedemann, Observation d’une grossesse chez une femme dont la matrice était double ; in the Journ. compl. des sc. méd., vol. vi. p. 371. — Mad. Boivin, Mémorial de l’art des accouchcmens , p. 85. it generally rests against one of the sides of the pelvis. b. Obliquity , in which its direction is from one side to the other. This state, especially when the uterus is unimpregnated, generally results from adhesions with the adjacent parts. c. Retroversion ,(2) in which the longitudinal diameter of the uterus corresponds to the antero-posterior diameter of the pelvis, so that its base is directed downward and backward, and its vaginal orifice upward and forward. This anomaly occurs particularly during the fourth month of pregnancy. d. Prolapsus, (3) where the uterus, most frequently from an inversion of the vagina, descends more or less into the pelvis. When the vagina is entirely inverted the uterus is depressed its whole extent, and the lower orifice is situated at the lower extremity of the tumor formed by it between the thighs. Usually also the neck is more or less elongated, and the uterus adheres to the primitively external face of the inverted vagina. From the elongation of the neck, however, the body of this latter is rarely situated on the outside of the sac of the vagina. In this deviation of formation the orifice of the uterus is rarely completely effaced. (4) Sometimes the uterus, even when it contains a fetus, forms a hernia. 2d. Abnormal form. One accidental anomaly in the formation of the uterus connects it with the proper deviations of formation, as it is attended with displacement of the organ. This is inversion, (5) which consists essentially in the turning outward of the inner face of the uterus. It appears in several degrees, for sometimes only the base of the uterus approaches the orifice, and sometimes it projects through this opening. The tumor it forms in this latter case differs from prolapsus, as its lower part presents no opening. This fact happens only when the cavity of the uterus is considerably distended and its walls are proportionally thin, and the organ is then compressed or drawn down by the base. Thus it is observed in parturition, in uterine polypi, &c. (3) Bœhmer, De prolapsu et invcrsione uteri, Halle, 1745. — It is figured in Ruysch, Obs. med. chir., obs. 2 and 8.— Baillie, Engr. fase. ix. fig. i. — Clarke, Diseases of females , London, 1814, tab. i-v. (5) Van Sanden, De prolapsu uteri, Leipsic, 1723.— Saxtorph, Auszüge aus der Abhandlungen der Copenh. Gelleschaft, Halle, 1785. — It is figured in Ruysch, Obs. anat. chir. cent., obs. x.— Denman, introduction to the praciiec of midwifery, tab. xii-xiv.— Baillie, Engravings, fasc. ix., fig. 2. Rupture is a deviation of formation of the uterus occurring under similar circumstances, although it is rare, except in a state of pregnancy ; it occurs when parturition is opposed by any cause, and is seen, particularly at the lower part of the organ, in a transverse direction. very great thinness and hardness of the hymen. Sometimes the vagina is divided in a greater or less extent into two halves by a longitudinal septum, directed from before backward, so that when the division extends to its lower extremity even two hymens exist. This anomaly may or may not be attended with an analogous state of the uterus. The vagina also presents primitive deviations of formation in respect to length and breadth. In fact it is sometimes extremely narrow and very short, which anomalies exist alone or together. The most common consecutive deviation of formation is the imperfect^) or perfect retroversion of the vagina, attending the prolapsus of the uterus. The bladder is then generally drawn downward, and very frequently also we find calculi, which may sometimes produce the disease, and sometimes have been produced by it.(2) § 2517. The external labia are sometimes deficient, from a primitive deviation of formation, or adhere to each other on the median line. These two anomalies result from the permanence of a primitive state of formation. (2) Ruysch, Obs. med. chir.. obs. i. — Paget ( Lond . med. andphys. Journ., vol. vi, p. 391) mentions a stone weighing twenty-seven ounces, attended with several smaller ones, found in a case of prolapsus of the bladder. § 2518. Sometimes also the nymphæ are deficient, or adhere. These two states may be primitive or accidental, and developed after an inflammation. In some cases they present an opposite anomaly, and are double or even triple.(l) Their unusual enlargement is commonly consecutive or accidental. f. Clitoris. 2519. The clitoris is sometimes unusually large, and then resembles the penis in the male, particularly when the urethra extends unusually far forward. Sometimes this part is enlarged in consequence of syphilitic affections, and its texture is altered ; it then becomes harder, firmer, and irregular. 2d. Smallness. 3d. Permanence in their primitive situations. This anomaly presents a great many degrees, from the case where the testicle remains below the kidney to that where the canal of communication, which continu es^some time after leaving the abdomen, is imperfectly obliterated. This last deviation of formation becomes the cause of congenital inguinal hernia. (2) See our Handbuch der pathologischen Anatomie, vol. L, p. 685. — H. Bosch* Diss. sistens obscrvalioncm de vcsiculæ seminalis sinislræ dejectu , integris lestibus , vase vero deferente sinislro clauso, Leyden, 1813. — Seiler haa published an excellent account of the post-mortem examination of a person affected with cryplorchis. § 2521. The prostate gland is particularly subject to enlargement, which is sometimes attended with a change in its tissue. In this case it is usually said to have become schirrous ; this assertion is true sometimes, but not always. Hypertrophy of the prostate gland often depends on the development in its substance of fibrous or fibro-cartilaginous formations, which are also as commorÉtn its corresponding organ, the uterus.(l) § 2522. The penis presents a great number of primitive deviations of formation, which depend principally on a suspension of development, or the permanence of a primitive form. They are : 3d. Total or partial imperforation, which presents several differences, either in respect to the degree or the quality, from the closing of the prepuce to the opening of the urethra in the perineum, which is or is not attended with the abnormal smallness of the penis ; in this case the lower part of the urethra, and consequently of the penis, are in fact cleft on their lower face. (2) 5th. The fissure of the penis at its upper face, which is often attended with that of the bladder, and which when existing alone makes the transition from this latter anomaly to the normal formation. When the organ is perfectly double, the two penises are situated one at the side of or one above the other. This last anomaly presents a remarkable analogy with the doubling of the tongue, the organ which corresponds to the penis. The first might be regarded as a greater development of the fissure of the penis. The consecutive deviations of formation comprehend the unusual enlargement of the penis, which commonly supervenes after the development of accidental formations. Their unusual smallness in the female and their abnormal size in the male constitute the first degree of hermaphrodism, especially when in the second case they secrete milk. Sometimes they are multiplied as in the mammalia. In the first degree of this anomaly one mamma has two nipples : next we find several mammae one above another, two and even three on each side, or on one only.* § 2524. Of all the parts of the genital system, alterations of texture exist most frequently in the ovaries ; here too the most different and the most regular new formations appear. The increase in the size of the ovaries must generally be attributed to the formation of these accidental productions, although it is sometimes, especially at first, only simple hypertrophy, either in the whole substance of the gland, or, as is more frequent, of one of its constituent parts, the vesicles. The enlargement of the ovary is often enormous, and to such an extent that the organ has been found weighing fifty- five, (2) eighty -five, and even one hundred and two pounds. (3) * Sometimes the supernumerary mamma; exist in unusual parts of the body. Dr. Roberts mentions a woman in whom a third mammae existed in the groin, with which she suckled several children. The least abnormal formation of this kind is dropsy of the ovary. (1) This state presents some differences. Sometimes, in fact, the liquid is contained in one pouch, sometimes it fills several vesicles, of various sizes. It also differs much not only in respect to quantity, -which is often enormous, but also, and even sometimes in the different cysts of the same ovary, in respect to color, consistence, &c. The cysts generally adhere to the substance of the ovary ; but we frequently also find them entirely loose and very numerous in the cavity of this organ, where they seem to have been produced by an effusion of serum. This morbid alteration depends sometimes on the increase of the vesicles of Graaf, sometimes on a repetition of these vesicles resembling the effects of generation, and consequently in a formation of serous membranes. Not unfrequently these serous membranes contain fat or adipocire. Beside the serous membranes, accidental mucous membranes are often developed in the ovaries ; these also have the form of cysts, contain a more or less dense fluid, and belong to the class of atheromata or melicerides. Another alteration in texture of the ovary, which frequently is seen alone or attended with the preceding, is the formation of fibrous, fibrocartilaginous, cartilaginous, or osseous substance, which is frequently developed in very large rounded masses, and also increases the weight* and size of the organ. To this we must refer, if not entirely at least in great part, the formations described as steatoma, sarcoma, scihrrus, osteo-sarcoma, and ossification of the ovary. To these abnormal repetitions of normal tissues, which frequently occur also ift the other parts of the body, but much less commonly than in the ovaries, we must add another, which is almost if not entirely peculiar to these glands. We mean the hairs and the teeth. (2) The hairs are much more frequent than the teeth, and are developed in the fat, and the teeth in the midst of cysts filled with a gelatinous mass, so that here the normal type is perfect, both in respect to the organ where the new formation occurs, as in that of the proportional frequency of its appearance. The nature of the organ in which these productions of bone, hair, and teeth occur, and which is the workshop of generation, the period of life at which they are most frequently developed, the fact that they have often been preceded by coition, finally the numerous cases of ovarian dropsy, have led many physiologists to consider them as the remains of a fetus which is developed in the ovary. But this hypo- (1) Fehr, De virgine , hydrope ovarii laborante, Strasburg-, 1762. — Huth, Casus rirginis hydrope ovarii extinclce, Strasburg, 1768. — Murray, De hydrope ovarii , Upsal, 1780. — Rossum, De hydrope ovariorum, Louvain, 1782. — Julia-Fontenelle, Analyse de quelques substances contenues dans les ovaires dans certains états morr bides ; in the Archiv, gén. de méd., vol. iv., p. 257. thesis is absolutely inadmissible : for the total disparity often observed in respect to number, form, and size, between these abnormal productions, and the remarkable fact that the hair, the bones, and the teeth are the only parts found thus, while in extraordinary pregnancies all the parts of the fetus are long preserved, prove also that the act of generation, if necessary to produce them, has not at least given rise to a perfect fetus, and is confined to developing the parts there found. Although in many cases the development of these more perfect formations, and also of all the other abnormal formations seen in the Gvary, undoubtedly arises from a copulation not sufficient to give rise to a normal organism, on account of the unhealthy state of one or of both the parents, their advanced age, or any other cause which weakens in them the power of generation : we cannot, however, admit that the male is necessary to produce them, since they have been found in very young girls, where the genital organs were perfectly untouched, and they have occurred in other parts of the body not only of the female but in the male. If they are more common and more perfect in the ovary than in any other of the organs, it is because the formative power is more energetic in this gland. We must not conclude from this that the union of the sexes must necessarily have preceded them, and still less are they the remnant of an ovarian fetus. The entirely abnormal alterations of texture are much more rare in the ovary, probably for the same cause, and because from the greater energy of the formative power, attempts to create new formations are there more frequently successful. An extremely rare alteration in respect to form, belonging exclusively to the ovary, and the nature of which has not yet been examined, is a large arborescence, formed of several solid tubercles united by filaments. This anomaly has been observed by Prochaska.(l) We also have before us two instances, which are recent. In opening the cadaver of a prostitute aged about thirty years, in whom were traces of an inflammation of the ovary, we found the tubes adherent and very thick, and farther the left ovary considerably enlarged, very soft, and changed into numerous eminences of different figures. In another cadaver of a woman forty years old, on the surface of the right ovary were three cysts about four lines in diameter, the inner face of which was very much folded, and presented similar circumvolutions. The first case was very probably the formation described by Prochaska, which perhaps might have appeared in the second, if the cysts had been torn, and their inner face had vegetated. Among the abnormal repetitions of normal tissues we may mention principally the fibrous, fibro-cartilaginous, or osseous bodies, which must be distinguished from schirrus, although they have frequently been described as such, on account of their hardness. These productions are rounded, sometimes distinct, sometimes united in great numbers, and adhere but slightly to the substance of the uterus. They generally appear on its external, but sometimes on its internal face, and have a yellowish white tint, and an irregular or more or less evidently fibrous structure. They commonly ossify in some parts, although their volume has no effect on this phenomenon. They are seen principally about the middle of life in unmarried females who have not borne children. The circumstances in which they occur in the last two places allow them to be considered as the imperfect products of generation. Those in the substance of the uterus are most frequently developed without the co-operation of the male, although they may be caused also by copulation. In this respect they resemble the abnormal formations of the ovary. It is very curious that the phenomena caused by them in both organs sometimes resemble those of pregnancy. (2) Not unfrequently even in these same circumstances other formations are developed in the cavity of the uterus, which may be considered as resulting from an ineffectual effort to produce a new organism, and which resemble either the deciduous membrane, or, when they have the form of thin vesicles filled with a serous fluid, the inner membranes of the ovum. The entirely abnormal alterations in the texture of the uterus are: 1st. Schirrous and cancerous formations. (3) This alteration does not appear, like the fibrous bodies, in the form of distinct masses ; it is formed by a change which generally commences at the lower part of the organ, and which gradually extends to the whole of it. The parts in which it is situated become at first hard, then swell more or less, afterwards suppurate in the same order, and are thus gradually destroyed ; abnormal openings are thus formed which communicate with the cavity of the abdomen, the bladder, or the rectum, or with several of these parts at once. Here as in all other cases of this change, the lymphatic system is infected, and death is the necessary consequence, (2) Cochon-Dupuis, in the Mém. de Paris, 1698, p. 339.— A. Monro, Four cases of the tumefied ovarium ; in the Med. essays of JEdinb., vol. vi., p. 278.— In two cases pains supervened ; in the first at nine months, in the other at ten. 2d. Polypi are developed on the inner face of the uterus so frequently that, in twenty cadavers, Portal has found them in thirteen. (1) They are distinguished, according to the place where they exist, into polypi of the base, of the body, and of the neck : and according to thendegree of solidity into soft and hard. They vary much in respect to number and volume. The vagina usually participates in the schirrus of the uterus, at least at its upper part. Polypi also are developed there, particularly at its summit, but much more rarely than in the uterus. 1st. Induration, a consequence of inflammation. 2d. Dropsy of the vaginal tunic, termed hydrocele. This disease is common. The liquid is commonly serous and limpid ; but sometimes also instead of serum we find a solid and opaque substance, or when this liquid is thicker and more viscous than usual, it contains shining laminae very similar to the fatty substance of cholesterine, but which differ from it, as their specific gravity is greater, and they dissolve more readily in the alkalies. (2) 3d. Ossification, which is situated principally in the epididymis and the vaginal tunic. We not unfrequently find in the albugineous membrane rounded plates of bone and cartilage, which are finally detached, and become loose in the cavity of the vaginal tunic. These productions are less common in the spermatic cord. in regard to this disease: He states that mollescence of the uterus is more frequently partial than general ; it more commonly occupies the internal surface and the cervix, though it occasionally extends through the substance of the organ. The mollescence presents several degrees, blending insensibly with each other. In the first, the parts are simply softened or very flaccid, generally with serous or sero-sanguineous infiltration into the nterstices. In the second degree, the structure of the uterus is still farther altered. It will scarcely bear handling without reduction into a pultaceous mass. In the third degree, the disorganization amounts almost to a liquefaction or reduction of the viscus to an inorganic pulp. — (Am. Journ. of the Medical Sciences , for November, 1828.) of lime. The mammæ of the male are subject to but few diseases. The alteration most frequent in those of the female is schirrus. We however designate by this term new formations, however much they differ, for almost all can be developed either alone or with others, in the tissue of the mammary gland.* I. ABDOMINAL CAVITY IN GENERAL. § 2528. After describing the digestive, the respiratory, the urinary, and the genital systems, we proceed to the topography of the abdominal cavity, (3) the general characters of which have already been mentioned. (4) § 2529. The upper wall is formed by the diaphragm ; the posterior , in the centre, by the lumbar vertebra and the sacrum, on the sides by the psoas magnus and the posterior part of the two broad internal abdominal muscles : each side is constituted above by the middle portion of these two muscles, and the posterior part of the obliquus abdominis externus, below by the ossa ilia and the descending ramus of the ischium, the anterior by the anterior part of the broad abdominal muscles, the rectus, the pyramidalis, the linea alba, the pubis, and its ascending ramus. The inferior by the muscles of the perineum. indirectly by the peritoneum. Hence the abdominal parietes are most solid in the posterior and inferior parts. We mayjudge also from the description of the mùscles which form them, that these also are enveloped in some parts more perfectly than in others. In the latter, the muscular layers are thinner and more feeble, or the muscles and their tendons are here entirely or in great part deficient. § 2530. Considered generally, the form of the cavity of the abdomen is oval. The umbilicus is situated at about the centre of its anterior face : the half above this cicatrix is a little larger and broader than the lower. The anterior wall is the longest. The sides are very short and almost straight. The posterior presents inequalities produced by the projection of the lumbar vertebrae and the sacrum. It is convex in the centre, at its upper part, and concave on the sides, particularly below. The upper and lower faces are more or less concave. D. CHANGES IN FORM AND SIZE. § 2532. As its parietes are formed mostly by muscles, it can vary much in form and size. The most important change is that which occurs regularly and constantly during respiration, and which depends on the alternate contraction and relaxation of the diaphragm. The action of the abdominal muscles also occasionally contract it more or less, to expel the substances contained in the intestinal canal, the uterus, and even in the bladder. The diaphragm and the other abdo- formly distended. § 2533. Besides the organs we have mentioned above, the abdominal cavity also contains the lower part of the aorta, the ascending venacava, the commencement of the thoracic canal, the great iliac trunks, the lower part of the ganglionnary nerve, and the lumbar and iliac plexuses of the last spinal nerves. All these parts are attached more or less by cellular tissue and in a larger or smaller part of their parietes, especially with the posterior, less to the superior, still less to the inferior, the anterior, and the lower region of the side ; the upper region of the selatter and of the anterior, is entirely loose, except a small portion of the anterior, to which the suspensory ligament of the liver is attached. Even where there is no continuity between the containing parts and those contained, the external faces of these latter are in direct contact with the internal face of the abdominal parietes, so that these faces can glide or play upon each other. As to their situation, the parts contained in the abdominal cavity differ principally in this respect, that most of them, viz. the upper region of the genital system of the female, and the whole digestive apparatus except the pancreas and the lower extremity of the rectum, are contained in the peritoneum, while the others, especially the great vascular and nervous trunks, the urinary organs and the lower part of the genital system, are situated out of this membrane. § 2534. The peritoneum, (2) the largest and the most complex serous membrane in the body, has a fibro-serous structure in some parts. It forms a sac, closed in every part except at the abdominal orifices of thoracique, Paris, 1820. (2) Wedel, De peritonœo, Jena, 1696.— J. Douglas, Description of the peritoneum and ofthat part of the membrana cellular is which lies on its outside , with an account of all the abdominal viscera, London, 1730. — C. G. Buttner, De peritonœo, Königsberg-, 1738. — F. G. Hewsing-, De peritonœo, Giessen, 1742. — H. A. Wrisberg, Deperitonœo diverticulis, illisque imprimis, quee per ombilicum et lineam albam contingunt, Gotting-en, 1780. — A. Vacca-Berlinghieri, Mémoire sur la structure du péritoine et sur ses rapports avec les viscères abdominaux ; in the Mémoires de la soc. méd. d'émul., vol. iii. p. 315. — C. J. M. Langenbeck, Commentarius de structura peritonœi, testiculorum tunicis, eorumque ex abdomine in scrotum descensu, ad illustrandam herniarum indolem, Gottingen, 1817.. the two Fallopian tubes, where it is continuous with the mucous membrane of these passages. It covers almost the whole cavity of the abdomen, except at the lowest part of the pelvis, and like all the serous membranes, it covers in two different modes the parts on the surface of which it passes. In fact, 1st, it envelops them all with its external layer, which has the form of a sac, but does not touch them ; 2d, Its inner layer is reflected in several places, and is fitted to the surface of the parts, and forms their external envelop. Several anatomists assert, that not only the parts enumerated above, but also all those situated in the abdomen, are contained in the peritoneum, which divides into an external and an internal layer to embrace them. This opinion arises from another, that the condensed cellular tissue on the outer face of the peritoneum, is a special fold of this membrane. But we cannot admit it, since this layer is not serous; it exists in every part ; it does not come from the division of the proper serous fold of the peritoneum, but it is formed by the scalpel, particularly when the parts are hardened by immersion in alcohol. § 2535. Like all serous membranes, the peritoneum is highly extensible, so that it does not tear when suddenly or gradually extended very much. Its solidity in the normal state depends upon this property. It is not equally firm in every part. The external layer is generally much stronger and thicker than the internal. It is strongest in the lumbar region, and at its lower and anterior part, and is weakest at its upper part. As its connections with the abdominal parietes are generally slight, it yields easily when drawn down, so that its situation and its relations with the adjacent parts change in a greater or less extent, when the testicles descend into the scrotum, or when a hernia exists, § 253G. We may distinguish in the external fold of the peritoneum, four parietes, an anterior, a superior, a posterior, and an inferior, the external faces of which arc almost in every part united to the internal face of the abdominal parietes. § 2537. The anterior wall covers the posterior face of the linea alba, the common anterior tendons of the broad muscles of the abdomen, and the anterior part of the fleshy portion of the transversalis muscle. It is attached rather loosely to the linea alba, adheres intimately to the anterior tendon, and is connected less firmly with the fleshy portion of the transversalis muscle. It is serous only at its lower part: but above it is covered on the outside by a very apparent layer of transverse and strong fibres, entirely distinct from those of the tendons terminate near the umbilicus by a semicircular edge. From the bladder to the umbilicus the urachus passes over its internal face, on the sides of which we observe the remains of the umbilical arteries, which separate below, are united in a single cord at their upper part, penetrate from without inward, and thus produce on the inside the prominences which have been called prolongations of the peritoneum [processus peritonei). On the inner face of the anterior wall we remark the suspensory ligament of the liver (L. hepatis Suspensorium) which descends from right to left to the umbilicus. It is a considerable triangular fold, expanded like a fan, the posterior edge of which is attached from before backward to the upper face. of the liver, where it separates the right from the left lobe, and in the lower and loose edge of which we distinguish the round ligament of the liver (L. hepatis teres), which extends from the umbilicus to the liver. Near the posterior edge of the muscle the peritoneum is reflected to the right on the liver, and not only covers the whole of this viscus, but also when it comes to the fissure of the vena-portæ, where it forms as it were a sheath, the fasciculus formed by the union of the hepatic artery, the vena-portæ and the biliary passages, goes on the upper part of the duodenum, to be continuous there with the small epiploon, the great epiploon, and the transverse mesocolon. From the right side, between the union of the posterior edge of the liver with the anterior, and the limit of the posterior, superior, and anterior walls of the peritoneum, we perceive a larger fold, which is the right triangular ligament of the liver (L. hepatis trianguläre dextrum ). A similar but much larger fold extends from the posterior edge of the small lobe of the liver, and from its summit, to the posterior wall of the peritoneum ; it is the left triangular ligament of the liver ( L. hepatis trianguläre sinistrum ), which is continuous forward with the superior ligament of the organ. In the place where the esophagus passes through the peritoneum, in proceeding through the esophageal fissure of the ^diaphragm, this membrane covers it in every part, and also in the upper part of the stomach. The folds which result from them are termed the right and left phrenico- gastric ligaments (L. phrenico-gastricum, dextrum , and sinistrum). The first is continuous with the small epiploon, and the second with the suspensory ligament of the spleen ( L . lienis Suspensorium), which is situated more to the left, between the upper extremity of the spleen and the posterior edge of the upper wall of the peritoneum. § 2539. The posterior wall descends from the upper and posterior edge of the liver, from the cardiac orifice of the stomach, from the left portion of the small curve of this viscus, and from the upper extremity of the spleen, above the lumbar portion of the diaphragm, then leaves the posterior wall of the abdominal cavity, and goes on the anterior face of the pancreas and duodenum, to which organs it adheres very slightly. After leaving the lower edge of the pancreas, the peritoneum goes downward and forward, and forms the upper layer of the transverse mesocolon, a broad and considerable fold, which receives anteriorly the transverse colon between its two layers, and the inferior layer of which is continuous with the lower part of the posterior layer. This lower part descends before the aorta, the vena-cava, and the kidneys, to which organs it slightly adheres, and afterwards goes without forming any fold, on the right or left, or at least without producing any except those which are very small, on the ascending and descending portions of the colon, goes also to the right side of the kidney towards the duodenum, the anterior face of which it covers, intimately uniting this whole intestine with the upper extremity of the ascending colon, and after covering all these parts, is continuous with the anterior wall, on the posterior portion of the transversalis abdominis muscle. Only the lower part of the descending colon and the commencement of the rectum, form a considerable fold on the central part of the psoas magnus muscle, and on the upper part of the sacrum. Tn the centre of the posterior wall is a fourth fold, directed obliquely from left to right, it descends from the second lumbar vertebra, and is termed the mesentery (mesenterium) . This fold, the root of which is very narrow, enlarges much at its loose edge, which embraces all the small intestine except the duodenum. It is continuous below with the right mesocolon, and gives off a small triangular prolongation, which serves as a mesentery to the vermiform appendage of the cæcum. D. INFEBIOB WALL. § 2540. We may consider as the lower wall of the external fold of the peritoneum, the part of this membrane which corresponds to the pelvic region of the abdominal cavity, and term it the pelvic portion. It is attached very loosely to the iliaci muscles, to the lower part of the abdominal muscles, to the levator ani muscle, and the sacral plexus. It is connected forward with the obturator internus muscle and the posterior face of the bladder. It covers posteriorly the upper part of the sacrum, but does not adhere to it strongly, and is reflected inward on the upper part of the rectum. muscle, to which it is loosely united. The anterior and posterior halves of this lower wall of the peritoneum, are adapted to each other, between the bladder and the rectum, so that in the male the anterior passes from the bladder upon the seminal vesicles, but does not touch them, and in the female, from the bladder upon the upper part of the vagina, and the lower part of the uterus, which it loosely envelops. Having thus arrived backward, it reunites to the posterior, which comes from the rectum, forming a greater or less cul-de-sac between this intestine and the parts we have mentioned. This cul-de-sac is limited on the right and left by two longitudinal folds, which extend in the male from the rectum to the lower part of the bladder, in the female from the intestine to the lower part of the uterus, and are termed the semilunar folds ( plieez semilunares). These folds are much smaller, and consequently the cul-de-sac is much less distinct from the rest of the peritoneal cavity, the more the rectum and the bladder, or the uterus are distended, because then the peritoneum is enlarged to cover its parts. The lateral wall of the pelvic portion of the peritoneum, forms in the small pelvis of the female a considerable fold, termed the broad ligament of the uterus (L. uteri latum). This fold is attached to the upper part of the vagina, to all the lateral wall of the uterus, to the Fallopian tubes, and to the ovaries, closely covers these parts, and lodges between its two folds the vessels and nerves which go to it. parated by the umbilical ligament, and by the prolongation of the (1) Hesselbach, Ueber den Ursprung der Leistenbrüche, Wurzburg', 1806. — Id., Ursprung und Fortschritte der Lcisten-und Schekcnlbrüche, Wurzburg, 1816. — Id., Disquisitioncs anatomico-pathologicœ de ortu et progressu herniarum inguinalium et cruralium, Marburg, 1816. — K. Liston, Memoir on the formation and the connections of the crural arch and on the parts contained in inguinal and crural hernia, Edinburgh, 1819. peritoneum which surrounds it, and which may he termed the inguinal fossæ ; they are distinguished into external and superior , the large, and internal or inferior , the smaller. At the place where the inguinal canal commences, we usually observe in the peritoneum a small depression, which is often connected with a cord formed of cellular tissue, which passes through this canal. This depression frequently forms a greater or less sac. It is always a remnant of the prolongation which formerly extended from the peritoneum into the scrotum. The external inguinal fossa represents a pyramid, situated between the peritoneal prolongation and the commencement of the inguinal canal. The internal is adapted on the median line to that of the opposite side, from which it is always more or less completely separated by the projection of the urachus. It corresponds directly to the inguinal ring. B. INTERNAL FOLD OF THE PERITONEUM. § 2541. The internal fold of the peritoneum which covers the outside of the parts situated in the cavity of the abdomen, is much thinner than the external. It is not arranged exactly in the same manner in regard to all the parts it covers, for it is attached directly to some, and to others only by more or less considerable prolongations. In several portions it extends on the almost loose part of the surface of the organs, and forms prolongations, which are sometimes loose and floating, and sometimes contribute also to unite one organ with another, independent of the common envelop. All these internal prolongations of the peritoneum, whatever be their relation with the organs, are formed of two layers, all the corrugated faces of which adhere to each other, while the smooth faces are loose and turned outward. We may then term them generally the folds of the peritoneum. Those which are shorter but broader, and which exist between the external fold of the peritoneum and the other parts, particularly the stomach, liver, spleen, &c., are termed the ligaments of the peritoneum ( L. peritonei). Their names are derived sometimes from their form, and sometimes from the parts which they unite. We have already mentioned most of them, in describing the external layer : and shall return to them when speaking of the epiploon. (1) J. S. Henninger, De mesenterio, Strasburg, 1714. — J. Fantoni, De mesenterio, vasis chylifcris et lymphaticis ; in the Diss. anat. renov. V. — Stock, De statu mesenterii naturali et præternaturali, Jena, 1755.— M. Malpighi, De omento, pinguedine et adiposis ductibus ; in Opp. omn., vol. i. p. 227 The last two lands of folds differ from all others, as they are extremely thin, so that many anatomists have even considered their reticulated or perforated structure as a normal arrangement. § 2543. The proper mesentery ( meseiiterium ) is directed obliquely from above downward, and from right to left ; it extends from the left side of the body of the second lumbar vertebra, to the right sacro-iliac symphysis. It is composed of two layers, a right and a left, which are separated in the upper two thuds of the mesentery, by the third or the ascending portion of the duodenum, but which unite beyond this portion, and in the lower third of the mesentery. The posterior edge, which rests on the vertebral column, is termed the root of the mesentery ( radix mesenterii). It is much shorter than the anterior, by which it is attached to the small intestine, so that its layers separate on arriving at the intestine, which they receive between them, and narrowly embrace them in all their extent. parts, to its centre. Its greatest breadth is about four inches. Between the two layers which compose it, and which are easily separated, are cellular tissue, fat, lymphatic ganglions, blood-vessels, lymphatic and chyliferous vessels, and nerves. It is continuous at its upper extremity with the transverse mesocolon, at the lower, with the triangular mesentery of the vermiform appendix of the cæcum, which is attached to the left side of its circumference, and the left side of which is perfectly loose, and continuous with the ascending mesocolon. Reebmann, De omento sano et morboso, Strasburg-, 1753. — P. Yan Nœmer, De fa hrica et usu omenti, Leyden, 1764. — Chaussier, Essai sur la structure et les usages des épiploons ; in the Mém. deVac.de Dijon, 1784. — Froriep, Neue Darstellung der Gehroses und der Netze, Weimar, 1812. immovably by the mesocolon. After covering the centre of the duodenum on the right side, the posterior wall of the peritoneum goes on the ascending portion of the colon, and covers it anteriorly, but not posteriorly, or at least but very rarely, where it is exposed on the anterior face of the kidney. Even when the ascending colon is entirely enveloped by the peritoneum, the fold which attaches it is always very short. upper part of the iliacus muscle. There are often detached from its summit two triangular folds, directed from right to left, and from above downward, which leave between them a depression, the base of which is formed by the iliacus muscle and the cæcum, and into which, particularly when the cavity is considerable, a greater or less portion of the intestine enters and is strangulated. The transverse mesocolon ( mesocolon transverswn ), which is uninterruptedly continuous with the ascending mesocolon, is an elongated quadrilateral fold, about four inches high, which extends from right to left near the centre of the abdominal cavity, and which is much higher in the centre' than on the sides. It arises on the right from the centre of the duodenum, in the centre from the anterior face of the pancreas, often also from the right side of the posterior face of the stomach, farther, and towards the left, from the extremity of the duodenum, and is attached to the transverse colon by its anterior edge. At its commencement on the right on the duodenum, it is continuous above and below with the portion of the posterior wall of the peritoneum, which covers the duodenum anteriorly, and intimately unites this intestine to the colon. Farther on the right, its upper layer closely unites with a greater or less portion of the great epiploon, so that hence, a quadruple layer from the duodenum to a greater or less portion of the right half of the great curve of the stomach exists, and this union of the right edges of the great epiploon and transverse mesocolon, always closes in this place the sac formed by these two folds. halves, a superior, smaller, and an inferior, which is larger. The descending mesocolon, the direct continuation of the preceding, is quadrilateral at its upper part, and does not generally surround the whole circumference of the descending colon. It arises from the upper part of the anterior face of the left kidney, but comes also in its centre, where it is more extensive, from the anterior fold of the posterior tendon of the transversalis abdominis muscle, finally below where it is larger than in any other part, and often also as broad as the transverse mesocolon, from the left psoas muscle and the sacro-iliac symphysis of the same side. 3d. From the commencement of the duodenum. It is adapted to the anterior part of the circumference of the transverse colon, goes before the small intestine, and generally descends into the pelvis, where it terminates by a loose edge. Its straight edge unites with the transverse mesocolon, and is attached by the left to the lower extremity of the spleen, and also to the left extremity of the pancreas and the transverse colon, uniting with the posterior wall of the peritoneum. § 2546. The small epiploon, epiploon gastro-hepatique ( epiploon hepatico-gastricum), descends from the fissure of the venous canal, from the left portion of the fissure of the vena-portæ, and the capsule of Glisson, towards the small curve of the stomach, from the cardiac to the pyloric orifice, and floats before the lobe of Spigel. The two epiploa communicate by the portion of the peritoneum which covers the anterior and posterior faces of the stomach, and thus forms, with the stomach, the anterior wall of a sac, the lower wall of which is constituted by the transverse colon and the transverse mesocolon, and the posterior by the upper part of the posterior wall of the peritoneum. The upper part of this sac, which is placed between the liver and the small curve of the stomach, communicates with the inferior, situated between the small curve and the transverse colon, by a greater or less opening, which is found between the posterior wall of the stomach and that of the peritoneum, in the part where the small curve of the stomach, near its right extremity, is not attached to the posterior wall of the peritoneal sac. The whole sac or the cavity of the epiploon communicates with the peritoneal cavity by the foramen of Winslow ( foramen Winslowii), a rounded, oblong opening, situated on the right side of the abdomen, bounded on the right by the fissure of the vena-portæ, forward by the Vol. III. 61 fasciculus formed by the vena-portæ, the hepatic artery, and the biliary passages, on the left by the first curve of the duodenum, and below by the posterior wall of the peritoneum, which the ascending vena-cava covers in this place. When we separate the liver and duodenum, and consequently remove from this latter organ the portion of peritoneum which extends from its summit to the liver, in forming a sheath around the fasciculus we have mentioned, a more or less broad, semicircular fold is formed, having its loose edge turned downward ; this is termed the hepatoduodenal ligament ( L . hepato-duodenale). We may produce also in the same manner an analogous fold between the first curve of the duodenum and the upper extremity of the right kidney. This last fold is the duodcno-renal ligament {L. duodeno-renale). c. Epiploic appendages. § 2547. The epiploic appendages ( Appendices epiploicœ) are short prolongations of the peritoneal tunic of the large intestine ; they are rounded, oblong, varying in breadth, filled with fat in fleshy people, and with a reddish, gelatinous liquid in lean persons. They arise principally from the anterior side of the edge of thjs tunic. They are generally arranged in two rows. These rows are situated on the outside and the inside of the intestine in the lower portion of the descending colon, on the lower edge in the transverse colon, finally on the internal and anterior edge in the descending colon. the intestinal extremity of the mesocolon than in the ascending colon. In the ascending colon, the epiploic appendages receive the external and internal branches of the mesenteric vessels. In the rest of the colon their vessels come only from the lower and internal branches of those of the intestine. I. REGULAR AND GENERAL DIFFERENCES. § 2548. 1st. The abdominal cavity is much larger in proportion to the chest, during the early periods of existence, than when the subject is fully grown, but its pelvic portion is infinitely smaller. 2d. Until the third month of pregnancy it extends by means of a prolongation, the length and the breadth of which are in direct ratio with the youthful age of the new being, and which incloses a portion of the intestinal canal, with the umbilical and omphalo-mesenteric vessels, in the umbilical sheath formed by the inner membrane of the ovum, so that this sheath then really makes part of it. The anterior cavity is covered by a prolongation which is also reflected on the viscera which it contains. In the fetus of three months, the anterior wall of the peritoneum extends already on the opening of the umbilicus, through which the umbilical vessels enter and depart, but does not give off in this place a prolongation which penetrates into the cord. We do not perceive at first any well marked difference between the general ligaments and the umbilical sheath ; but this difference is seen in proportion as the development of the skin progresses. Hence in the full-grown fetus the root of the umbilical cord is surrounded by a cylindrical fold of skin, which is about four lines long, and is usually more distinct from the umbilical sheath on the right side than the left,(l) the inner face of which is strengthened by some fibres of the lineaalba. The umbilical ring is much broader the younger the fetus is. It gradually contracts, and in the full-grown fetus it exactly surrounds the umbilical vessels. Its lower part particularly is intimately united with the umbilical artery by a short and firm cellular tissue ; the cellular tissue which unites the upper with the umbilical vein is looser. The umbilical ring is already surrounded in the full-grown fetus with very strong and perfectly developed tendinous fibres, while the linea alba, less advanced in all these respects, is formed only of indistinct and proportionally shorter and narrower tendinous fibres. After birth the portion of the cord left on the body of the infant dies in its whole extent where it is covered by the umbilical sheath. Instead of the cylindrical fold of skin, there forms a depressed cicatrix, the navel or umbilicus , the depression of which depends principally on the disappearance at this period of the prominence previously formed by the umbilical vessels and the gelatine of Wharton. It depends also on the general law that the cicatrices of the skin are attended with a greater or less contraction. The collapsing of the umbilical vessels also assists to form it. Afterward the depression increases as much more as there is fat deposited in the surrounding parts, for this fluid never accumulates in the cicatrix. The umbilical ring and the peritoneum gradually adhere very intimately with the cellular tissue and the skin which covers them. In the book on embryology we shall mention the changes in the umbilical vessels. 3d. In the male and female fetus, the peritoneum forms another culde-sac, the diverticulum of JYuck ( diverticulum Nuckii), which extends through the inguinal canal and inguinal ring. This diverticulum is connected with the development of the testicle in the male. It has even the same use in the female, but as it here receives no organ it is much narrower and shorter, and often disappears before the end of the last month of pregnancy. The great epiploon appears in the second month of pregnancy. Until the fourth there exists only a simple prolongation of the peritoneal coat of the stomach, which is not yet connected with the transverse colon. § 2549. The abdominal cavity is considerably distended during pregnancy : but it returns almost entirely to its normal dimensions after parturition. We have not observed any marked difference either in the region of the umbilicus or in other parts, even in those females who have had several children, nor has Sœmmerring.(l) But the skin being much less extensible, wrinkles are formed in the general integuments of the abdomen by pregnancy, which are not seen in females who have had no children. C. DIFFERENCES RELATIVE TO SEX. § 2550. The abdominal cavity is smaller in proportion to the chest in the male than in the female, in whom it is much longer and narrower at its upper part, but much broader in the lower, that is, in its pelvic portion. The hairs of the pubis also differ in their arrangement. In fact in females they suddenly cease, and occupy only the centre of the space between the umbilicus and the symphysis pubis, while in the male they extend in a point to the umbilicus. § 2551. 1st. When the upper half of the body is not perfectly developed, in acephalia vera, the abdominal cavity presents more or less the same deviation of formation at its summit, so that sometimes only the pelvic portion exists, and this also is frequently narrower than in the normal state. often distend it very much. 2d. Curvature of the spine, which sometimes, but very rarely, constitutes a primitive deviation of formation, naturally causes a greater or less alteration in the form of the abdominal cavity and the situation of the parts within it. 3d. This cavity not unfrequently presents anomalies depending on the permanence of one of the degrees of formation through which it successively passes, that is, the openings and prolongations first existing at its upper or lower extremity do not disappear in a greater or less portion of their extent. This causes congenital umbilical hernia, and the abnormal communication between the vaginal tunic of the testicle and the cavity of the peritoneum, which give rise to congenital inguinal hernia. Frequently also the connections of the abdominal parietes with the parts contained in this cavity, particularly those of the external and internal layers of the peritoneum, are abnormal. tive deviation of formation. It is generally consecutive. It is much more common to observe unusual connections, adhesions, which are generally the consequence of an inflammation of the peritoneum, and which are caused by effusion. Sometimes even in this case all the organs surrounded by the peritoneum are so blended in one mass that they cannot be perfectly separated ; but they generally adhere only in some parts. If the adhesions occur so that they produce a kind of bridge between the two parts, this arrangement may induce in the cavity of the abdomen the same consequences as certain solutions of continuity, as an opening also results from them ; but this is a subject naturally connected with that of internal hernias, of which we shall speak hereafter. 4th. The abdominal viscera are not unfrequently displaced. Most of these displacements are termed hernias, ( 1) which term includes every abnormal situation of a viscus which leaves the cavity in which it is normally situated, or which enters into a generally abnormal compartment of the cavity in which it is situated. § 2552. The most important points in the history of hernia are, the relations of the displaced parts with the integuments, the nature of the herniary parts and the changes in them, finally the place where the hernia occurs, and the peculiar phenomena presented by each species of hernia in the first two respects. 1st. JYature of the envelops. Beside the integrity of the common integuments, which occurs first in most hernias, the most general condition of this anomaly is the existence of a herniary sac, produced by the elongation of the peritoneum. The internal hernias differ in this respect from the external : for the parts which have passed through an abnormal opening in the cavity of the abdomen are not surrounded with a herniary sac. Besides sometimes we find no sac in the external hernias, whither it has never existed, as when the peritoneum is torn, or it has been destroyed by compression, suppuration, gangrene. rupture of the peritoneum. On the other hand the peritoneum and thè cellular tissue which surrounds it externally gradually thicken and become harder to some extent, particularly at the entrance or neck of the herniary sac, which happens particularly after long compression. (1) J. G. Gunz, Observationum anatomico-chirurgicarum de herniis libellas , Leipsic, 1744. — G. Vogel, Abhandlung aller Arten der Brüche, Leipsic, 1756. — P. Pott, 'l'reatise on ruptures, London, 1756. — J. T. Klinkosch, Programma quo divisioncm herniarum novamque herniae ventralis speciem proponit , Prague, 1764. — Arnaud, Mémoires de chirurgie, London, 1768, vol. ii. — A. T. Richter, Abhandlung von den Brüchen, Leipsic, 1778. — Monteggia, Qucedam de hernis ; in the Fase. anat. path., 1793. — J. and C. Wenzel, Eilf Beobacktungenueber Brüche ; in Loder, Journal für Chirurgie, vol. iii. pt. ii. 1800, p. 217-258. — A. Monro, The morbid anatomy of the human gullet, p. 363-542.— J. F. Meckel, Handbuch der pathologischen Anatomie, vol. ii. pl. i. p. 358-484. — A. Scarpa, Traité pratique des hernies, Paris, 1812-1823. — Lawrence, Traité des hernies, Paris, 1818. J. CÎoquet, Recherches anatomiques sur les hernies de l’abdomen, Paris, 1817-1819. — Breschet, Essai sur la hernie fémorale, Pari3, 1819. tions with the herniary sac. a. Hernia is most generally formed by a portion of the small intestine or of the epiploon, more rarely by a portion of the large intestine, still more rarely by the liver or a portion of the urinary or genital organs. We however possess several instances of hernia of the uterus, the ovaries, the Fallopian tubes, and the bladder. An intestinal hernia usually includes all the circumference of the intestine. We rarely find in it only a portion of the surface of the organ. b. The herniary parts are abnormal, either in respect to their situation only, or also in their functions and texture. This latter case happens particularly when, from a want of proportion between the capacity of the herniary sac and the volume of the part displaced, this latter is compressed, strangulated, whence it inflames, and even becomes gangrenous when the disproportion continues. If gangrene occurs, the herniary portion is separated from that which is contained in the abdominal cavity, which causes, when hernia of the intestine exists, the formation of an abnormal opening termed an artificial anus. Some and even large portions of the intestinal canal may be destroyed, although no feces escape into the abdomen, and without the close of the natural opening. This close in fact occurs sometimes from the effusion of fibrin all around the opening produced by the gangrene, which is obliterated at first on the side of the cavity of the intestine, then externally. It occurs even in some cases where there was not the least direct communication between the upper and lower ends of the intestine. c. The herniary parts do not generally adhere at first to the herniary sac, excepting their envelops, as when, for instance, in the hernias of the ascending or descending colon, the displaced part is primitively united to the sac : but afterward, exsudation which succeeds inflammations of the serous membranes so rapidly, causes.the serous membrane of the herniary sac to adhere more or less intimately with the displaaed viscus. The hernia is then said to be adherent. 3d. Certain regions of the abdomen are more subject to hernias than others ; particularly those which have a sloping situation, and which on account of their structure, are but slightly resisting. The most common hernias are bubonocele and merocele, which take place, one through the inguinal ring, the other through the crural arch. The inguinal hernias become scrotal when these viscera descend into the scrotum. The bubonocele is more common in males, and the merocele in females. Next come the umbilical hernias, then the ventral , next those through the foramen ovale , then the phrenic , and lastly the ischiatic and the lumbar. a. In inguinal hernia, the viscera always emerge through the inguinal ring, but do not always come there in the same manner. In the external or oblique inguinal hernia, which is infinitely more common than the other, the viscera emerge through the inguinal anal, so that the tumor has at first an oblique direction ; on the contrary, in the internal or right inguinal hernia, it proceeds directly from above downward, towards the ring on the inside of the old umbilical artery, and passes through or distends the lower part of the broad internal abdominal muscles which are situated before it. Hence the differences between these two hernias, in respect to their envelops and the relations of the tumor with the adjacent parts. The external inguinal hernia is inclosed in all the envelops of the spermatic cord, consequently, in the cremaster muscle and the common vaginal tunic. The spermatic cord is situated behind the tumor, and follows the same direction. The epigastric artery is reflected from without inward, and from below upward, behind this tumor. The form of the hernia is oblong, at least at first. The internal inguinal hernia is not generally enveloped by the cremaster muscle and the vaginal tunic, but only by the cellular tissue of the scrotum. It is situated on the inside of the cord, does not pass before it, and sometimes is found behind it. The epigastric artery ascends at its inner side, and its form is rounder. Although these differences occur generally, the rule is however subject to exceptions. Thus in one case, the cremaster muscle evidently passed on the anterior face of an internal inguinal hernia. (1) In another case, the spermatic cord proceeded transversely on the neck of an internal hernia, towards its inner side, and farther, near its posterior side.(2) Finally, in a third, the epigastric artery ascended to the inside of the tumor. (3) Congenital hernia is a variety of external inguinal hernia, in which the viscera descend in the unobliterated prolongation of the peritoneum, and are consequently situated in the same cavity as the testicle, which even sometimes adheres to them before leaving. We must also compare with external inguinal hernia, that recently described as the infantile hernia, where the displaced viscera are engaged in the vaginal tube. This hernia may present two forms. Sometimes, in fact, the vaginal tube is open its whole extent, both on the side of the testicle and that of the abdomen, and sometimes only on one side. In the first case the herniary sac does not touch the testicle, as does the organ displaced in congenital hernia. In the second, when the vaginal tube is open at its upper part, the hernia is enveloped by a second sac, which forms it, exactly as in any hernia, the part contained in the sac is by this sac. When, on the contrary, the tube is closed above, the sac occupies also the upper part of the vaginal tunic, but in a still more complex, since this tunic sends to it two envelops, an external and an internal. OF THE ABDOMINAL CAVITY. pushed back at its upper part, and reversed by the hernia, whence in this case the sac is smooth externally. We conceive that in ail these cases the number of the envelops of the hernia is augmented, and that it is really provided with a double sac. In the first it may be complicated with a common congenital hernia; in the second also, two hernias may coexist. (1) Inguinal hernia is much more common in the male than in the female, because the inguinal ring is broader in the male, and the vaginal prolongation remains open much longer in him. b. Crural hernia takes place below the crural arch. It is rounded, and is generally situated on the inner side of the crural vessels, before the epigastric artery, usually also before the obturator artery, even when the latter comes from the epigastric artery, sometimes, however, behind it. Its neck is situated in the male directly below the upper part of the spermatic cord ; in the female below the lower part of the round ligament of the uterus. It is more common in the female than in the male, on account of the greater distance between the symphysis pubis and the anterior extremity of the iliac crest. c. Umbilical hernia occurs either through the umbilical ring, or in its neighbourhood, through a fissure in the linea alba. The first case is the most common when the tumor exists as soon as the child come3 into the world, and depends on suspended development. The second is still more so when the hernia is formed there accidentally. It frequently has a rounded form, and is rarely oblong. inguinal region, around the ring. e. Ovular hernia(2) occurs through the space at the upper and outer part of the foramen ovale. It is then situated very deeply before the obturator vessels and nerves, below and behind the adductor muscles of the thigh. f Phrenic hernia(3) supervenes in very different parts of the diaphragm, and it is destitute of a sac more frequently than any other hernia. It is congenital much more frequently than accidental, which undoubtedly depends on the necessity of extreme violence to produce it, for since when it occurs the viscera are displaced in a direction opposite to their weight. g. and h. Hernias through the sciatic notch and the lumbar region, are extremely rare. The second has no peritoneal envelop, and is generally formed by the kidneys. (1) We have enlarged a little on this subject, because it does not seem completely exhausted by Todd’s remarks, since the publication of our Handbuch der pathologischen Anatomic, vol. i. pt. 2. p. 416. 1st. Abnormal openings exist sometimes in the internal portion of the peritoneum, that which always occurs, and sometimes form after partial adhesions between parts which should be separated. Those of the second class may be developed in all parts. We have observed almost all of them in cadavers. The partial adhesions which give rise to them, may take place, d. At the summit of a diverticulum of the ileon, especially by a filament which still exists there, and which is formed by the remnant of the omphalo-mesenteric vessels. (3) /. Between the epiploon and the base of the uterus, or any other abdominal organ, or even the parietes of the peritoneum. It is the most common of all the adhesions.(5) 2d. Abnormal depressions are formed by the mesentery, (6) the bladder,^) the vagina. (8) In the last case the bladder is situated in the wall of the vagina, particularly the anterior, which is then turned over. (9) (5) Ruysch, Obs. anat., 65. — Monro, Anat. of the gullet, p. 533. — J. P. Weidmann, Memoria casus rari in gynœceis prœcipue adnolandi ; cum uteri anticâ facie omenti margo ex aliquâ parte coaluerat ; prœgnans fœtu, medium graviditatis non assecuta, inopinato moritur, Munich, 1818. — Gartshore, in the Med. obs. and inq., vol. iv. p. 223. — Haen, Rat. med., pt. ii. c. iii. § 2. — Knoblauch, Diss. de entero-mcsoeqtocele, Leyden, 1767. (6) Neubauer, Descript, anat. rarissimi peritonæi conceptaculi tenuia intestina a reliquis abdom. vise, seclusa tenentis, Jena, 1776. — Van der Kolk, Diss. exhibens observ. varii argumenti, Groningen, 1793. — Lawrence, loc. cit. This membrane is frequently inflamed in a greater or less extent, and thus more or less broad and firm adhesions are formed. Inflammation of it also produces either in its external or internal layer, an induration, a thickening which is often very great, several lines in extent. This alteration is caused particularly by a long continued inflammation. We may also mention another which depends on the same cause, and is almost peculiar to the peritoneum : it is the development on its inner face, of numerous small miliary elevations. The abdominal cavity is very frequently the seat of dropsy, which is there called ascites. Serum most generally occupies the whole cavity : in some cases only the epiploa are filled. Ossifications on the external face of the peritoneum are rare : but we frequently see them at intervals on its internal face, particularly on the surface of the spleen. The epiploon sometimes presents a similar formation.^) Rounded, cartilaginous, and osseous masses, similar to those found loose in the articulations, are rarely developed on the inner face of the peritoneum : they finally become loose, leaving their attachments. Hairs occur in the epiploon still more rarely. We not unfrequently find on the two faces of the peritoneum, and in the epiploa, serous cysts, and larger or smaller masses of hydatids. The serous cysts also are sometimes detached and become loose. (4) epiploa and the mesenteries, also are frequently the seat of accidental (1) J. G. Walter, De morbis peritonœi, Berlin, 1787. — Goelicke, De mesentcrii affcctibus, Halle, 1742. — Stock, loc. cit. — Rcebmann, loc. cit. — Haider, De morbis omenti, Gottingen, 1786. — A. Portal, Observations sur les tumeurs et engorgemens de V épiploon ; in the Mém. sur plus, maladies , vol. i. 1800. p. 67.— Scoutetten, Mémoire sur V anatomie pathologique du péritoine ; in the Archiv, gcn. de méd., vol. iii. p. 497; vol. iv. p. 386; vol. v. p. 537. — D. V. Yan Leuwen, De peritonœo ejusque infiammatione, Utrecht, 1819. formations, of more or less solid whitish substances, which are described as atheromata, steatomata, &e., and which frequently become heavier than the fatty tumors mentioned above. cavity of bile, blood, or of the contents of the intestines or the uterus. The air which sometimes fills the cavity of the peritoneum, or only that of the epiploa, comes from the same source in some cases. But probably this is not always its origin, for sometimes, although very rarely, this fluid is exhaled by the vessels, the action of which is changed. EMBRYOLOGY. § 2555. When all the parts of the body have acquired their respective and normal proportions, and the genital organs also are perfectly developed, the individual is fit to propagate the species by connection with an individual of the other sex. In describing the perfect state of the genital system, we have already mentioned the conditions on the part of these organs, in order that coition may be productive. The connection of the two sexes causes in the female those changes which result in producing a new organism, and which is termed conception^ 1) ceive no trace of it before coition followed by impregnation. (1) The works we shall mention treat more or less perfectly of the changes in the organism of the female and of those in the new being: — J. C. Aranzi, De humano fœtu libellus, Venice, 1751. — Fabrice of Aquapendente, De formata fœtu , Padua, 1604. — G. Harvey, Exercitationes de generatione animalium, London, 1651. — C. Drelincourt, De conceptû, Leyden, 1685.— M. R. Besler, Admirandæ fabriccc humanes muliebris partium generationi inservicntium et fœtus fidelis quinque tabulis, hactenus nunquam visis , delineatio, Nuremberg, 1640. — Haller, Historia nuperœ dissectionis feminœ gravidœ, Gottingen, 1734. — G. Noortwyk, Uteri humani gravidi anatome et historia , Leyden, 1743. — D. Monro, The dissection of a woman with child, and remarks on gravid uteri ; in the Ed. phys. and liter, essays, vol. i., art. 17. — A. Monro, Additional observations on gravid uterus ; ibid., art. 18. — J. G. Rcederer, leones uteri humani observationibus illustrates, Gottingen, 1759. — C. N. Jenty, Demonstratio uteri prœgnantis mulieris cum fœtu ad partum matur., Nuremberg, 1761. — Azzoguidi, Observationes ad uteri constructionem pertinentes, Bologna, 1773. — G. Hunter, Anatomia uteri gravidi tabulis illustrata, Birmingham, 1774.— E. Sandifort, De utero gravido ; in the Obs. anat. pathol., vol. ii., Leyden, 1778. — J. Burns, Anatomy of the human gravid uterus, Glasgow, 1797.— Moreschi, De utero gravido, Milan, 1817. — Maygrier, Nouvelles démonstrations d'accouchc•mens, Paris, 1822. — Mad. Boivin, Mémorial de l’art des accouchemens, Paris, 1824. 2d. The most general condition necessary to produce it is the action of the normal seminal fluid of the male on the genital organs of the other sex, in a state of maturity, and when their vitality is exalted, male produces conception. On this subject there are two opinions : 1st. Some admit that the semen arrives at the ovary through the uterus and the Fallopian tube ; that it causes directly the changes which occur in this organ, and even that its substance unites more or less in the uterus with the product of the ovary, to give rise to the new organism. 2d. Others think that the semen does not act on the ovary directly, but only secondarily, by a change which it causes in the whole organism or in the genital organs, and does not contribute by its proper substance to form the new organism. The principal facts in support of the first hypothesis are : 1st. The necessity of a channel for the semen, in order that the impregnation may occur, since it does not happen when the cavity of the female genital organs is interrupted. males who died during or shortly after coition. 3d. The necessity of copulation even to produce a new organism, for it is difficult to admit that impregnation may occur equally in any part of the body destitute of an epidermis, or at least covered by an epidermis as thin as that of the genital organs, as has been asserted. (2) the hypothesis they are adduced to support : 1st. In regard to the first argument, sterility may possibly depend on other causes, and besides it would follow only that the semen must necessarily act on a certain organ, as the uterus or vagina, in order that impregnation may occur. 2d. Perhaps the fluid found in the uterus and Fallopian tubes was not semen, but was secreted by the female genital organs, and this is often found in the cavity of these two organs. 2d. In careful experiments on generation semen has seldom been found in the uterus, and the consequences of conception are not manifested till several days or weeks after coition. 3d. In most animals the genital organs are so arranged, that on account of their length and tortuousness in the females, the marked prominences on the neck of the uterus, and the shortness of the male organs, it seems almost impossible for the semen to arrive at the ovaries. which attend impregnation. Hence it follows that the influence of the male is confined to exalt the formative power in the female to the degree necessary to produce the new being. This increase is manifested, as we shall soon state, by the direct formation in the ovary of a new organ, a temporary testicle , which secretes a fluid possessing the power of spontaneous growth. § 2557. Coition usually changes the external genital organs very much ; the hymen is generally more or less perfectly destroyed. Its remains give rise to the cancnculoi myrtiformes , which term applies to three or four small eminences, most generally triangular, which are situated on the sides and posterior parts of the vagina. The existence of the hymen is not, however, a certain mark of physical virginity : first, because this membrane has frequently been found, not only in females who had several times had connection, (3) but also in others who had given birth to fetuses more or less advanced, and fetuses even tion, but only by conception. A special body, termed the yelloiv or glandular • body {corpus luteum , s. glandulosum),{3 ) is developed in the ovary. It is a rounded, soft, very vascular tissue, composed of several lobes ; it projects above the surface of the ovary, becomes about as large as a cherry, and incloses a cavity which opens externally. The number of the yellow bodies usually corresponds to that of the new organisms which have been formed. From experiments on animals, these bodies arise from the change of one and not probably of several of the vesicles of Graaf, which, from being a simple serous membrane, is changed into a glandular organ, that is, its organism becomes more complex, and it acquires the faculty of producing a liquid different from the serum of the vesicles. As the yellow body differs in its structure from all the other glands, the fluid it secretes has also peculiar characters : it is the generating fluid, the semen of the female. The influence of the male semen is the usual and regular cause of this change, which however seems to occur also from the effect of other stimuli, perhaps of the imagination or unnatural indulgences. In fact several rare cases, where yellow bodies have been found in unmarried females and virgins, and always attended with the phenomena mentioned above, lead us to think that the formation of these bodies had been preceded by the act of coition, and by impregnation. However as they have been found in animals generally sterile, as mules, our opinion as concerns females is very probable ; but we are not authorized by facts to think that the change of the vesicles of men, which is very remarkable. (2) M. Malpighi, De cornuum vegetationc, utero , viviparum oris ; in the Opp. omn., Leyden, 1637, vol. i. p. 211.— A. Bertrandi, Observations sur les corps glanduleux, sur la matrice et sur l'ovaire dans l'état de grossesse; in the Miscell. l'aur., vol. i. 1758. Some have mentioned yellow bodies found in newly born or very young animals ; but it is easy to reply to this objection that every yellow substance found in the ovary is not a yellow body. Nor is the argument drawn from the fact that the number of the yellow bodies does not always correspond to that of the offspring, conclusive. If the number of yellow bodies be fewer than that of the offspring produced by the female, this circumstance agrees with their signification, since one yellow body as well as one testicle may produce several new or. ganisms. Farther one or more of these bodies also might disappear or several be blended together. In the case where they were more numerous than that of the offspring : 1st, it is necessary to mention exactly if these which were supernumerary did not arise from anterior conceptions ; 2d, it would be possible, even in admitting that the animal has never conceived previously, that generation has not proceeded beyond the production of a yellow body, or that its production was lost. Besides we are very much disposed to consider as very uncertain, observations in the cases where it is pretended that the number of yellow bodies and that of the offspring differed, for the examination of more than two hundred women, and females of different mammalia in the state of pregnancy, has convinced me, that the number of yellow bodies which from the absolute identity of all their characters may be considered as produced by the same generating act , always corresponds to that of the young. Observers known for their correctness have come to the same conclusion, (2) while contrary assertions do not appear to be well supported. The cavity of the yellow body is gradually obliterated ; the body itself diminishes, collapses, and hardens. These changes do not happen exactly at the same period, and we have remarked generally in the human species or in animals, at least in respect to the size of the body, they are not very large during pregnancy, while after parturition they evidently increase more rapidly. This phenomenon is worthy of notice, as it teaches us that although the function of the yellow body and the ovary generally has passed at this period, vitality however continues to be more active in them on account of the great degree of vitality in the uterus. Farther the yellow body rarely disappears entirely, although it diminishes extremely. § 2559. According to Osiander(4) the vesicles of Graaf and the yellow bodies have no connection with generation, because the former have no openings. He asserts that after coition the parts which are changed into new organisms are developed on the surface of the ovary in the form of miliary vesicles, one of which is detached and falls into the uterus. He adds that we must consider these corpuscles as ova : 1st, because they never appear before impregnation ; 2d, because they are always observed after coition followed by impregnation ; 3d, because many are found in the cadavers of young females dying after a few pregnancies ; 4th, because many are turgescent, others empty, and finally others resemble simple cicatrices ; 5th, because they disappear entirely when the female is sterile. These reasons do not seem satisfactory to us. The vesicles mentioned may be developed after copulation and disappear during life, although there were in fact no ova, since coition, when followed by conception, produces as great and to a certain extent even analogous changes in remote parts and in the whole organism. Besides we have frequently found the ovaries of females, physically and morally virgins, covered with a very dense miliary eruption, and in them the vesicles were too numerous to admit Osiander’s opinion in respect to them. of the changes in the vesicles of Graaf after impregnation. The only argument adduced by Osiander to reject the use attributed to the vesicles of Graaf has no weight except against an unimportant opinion, that the vesicle itself is detached, and that the yellow body grows in its place ; but this has no weight at all when, as seems to us more correct, we consider the yellow body a vesicle’changed, which, according to all observations, is provided on the surface of the ovary with an opening communicating with its cavity, and through which the formative fluid may escape. § 2560. The only change produced by coition in the Fallopian tubes is this ; soon after this act they are applied to the ovaries, so as to embrace a greater or less portion with their fimbriated extremity, then carry into the uterus. Their approximation to the ovaries is favored by the portion of small intestine situated in the lower pelvis ; for this portion tenses the ligaments of the ovaries and the broad ligaments of the uterus, thus fixes the glands in their position, and applies the tubes to their surface, so that they extend a little on the outside of them.(l) changes in many respects, and the new organism is developed within it. Even before we perceive any trace of the new being, we already find the uterus a little enlarged at its upper part, its substance is softer, looser, more lamellar, its component layers are more distinct, its vessels are dilated, its inner face is smooth but irregular, extremely vascular, and also covered with numerous very minute flocculæ, which cannot be seen except with a microscope, and finally it is covered with a pultaceous matter into which the vessels extend, and which passes on the neck of the organ, so as to close the cavity of the body. This substance resembles coagulated blood. It is thickest at its upper part, where it is connected with the uterus more intimately than in any other place. Below it is very thin and united to the organ more loosely, and even does not adhere to it at all. (3) which generally continues ten lunar months. The fibrous texture becomes more and more distinct : it cannot well be perceived(4) except during pregnancy or in analogous states of the uterus, when this organ also enlarges, as for instance, when abnormal formations are developed within it. It is then certain that if the fibres do not form during pregnancy they are at least developed and very much enlarged at that time. (2) Beside the works already mentioned in respect to the uterus, consult also : A. Vater, De utero gravido, YVittemberg-, 1725. — Beyer, Utrum in gravidis lotus uterus cequaliter extendatur , Paris, 1729.- — P. A. JBoehmer, Situs uteri gravidi fœtusque , ac sedes in utero, Halle, 1748. — B. S. Albinus, Tabulce uteri gravidi, Leyden, 1748. — Id., De utero gravido nonnulla ; in the Annot. acad., 1. ii. cap. v. — J. Weitbrecht, De utero muliebri (gravido) observationes anatomicœ ; In N. C. Petrov., vol. i. p. 337. (3) Pke case of a young woman who poisoned herself in the first month of her pregnancy, by 'Ph. Ogle ; to which is added an account of the appearances after death, by J. Hunter ; in the London med. trans. for the improvement of med. and chir. knowledge, vol. ii. p. 63. softer, is not only distended but enlarges considerably. Some days after parturition occurs, when the term of pregnancy has been normal, the uterus weighs at least twenty-four ounces, as we have proved by examining twelve cadavers of females dying at this period ; so that even then, although the organ had already collapsed, its weight was to that of the uterus in a virgin as 24 : 1. Another question now presents itself, viz. do the parietes of the uterus, which, from the preceding remarks, are not only distended, but also become thicker, remain the same, or do they grow thinner ? The latter perhaps is true, notwithstanding the increase in mass and weight, on account of the considerable extension of the uterus during pregnane}^. Those who admit that the parietes of the uterus preserve the same thickness, or even become thicker, explain the contrary assertion by saying that the thickness of the uterus, considered generally, varies in the state of pregnancy, (2) and that an uterus, when filled with the product of conception, has not the same thickness in every part. (3) We may also say that sometimes the uterus, from a pathological state, is not properly developed, and is only distended, which perhaps is one of the causes which contribute to render parturition painful. Our observations made upon sixteen uteri at all periods of gestation, lead us to think that very probably the parietes become a little but not much thicker at first, and that towards the end of pregnancy they gradually become much thinner. In fact we have found the parietes of the uterus six lines thick, three weeks after conception ; five, at the beginning of the third month ; four, at the commencement of the fourth ; at the end of this month, four in two cases: three at the upper part, and four at the lower in a third, and five in a fourth case ; at five months, three lines thick in one case, two at the upper part, and four in the lower in another ; at six and seven months, a little less than three ; at eight months, from two to two and a half lines in one case, and in another, three lines at the upper part, and more than four at the lower : they have appeared to us a little thinner at nine months. rally an inch thick at the end of seven, eight, and nine months. The veins and the arteries of this organ are extremely dilated, so that the venous trunks are as large as the axillary veins. These two orders of vessels become less tortuous as the uterus enlarges. insertion of the placenta. § 2562. The form of the uterus is also considerably changed. As the body only of the organ is developed during most of pregnancy, the disproportion between it and the neck always becomes greater, and even, as when the neck is finally distended, in the latter periods of pregnancy it shortens in proportion as it enlarges, the disproportion only becomes still more perceptible, so that the uterus is rather oval than pyriform, especially near parturition. This organ also becomes considerably thicker from before backward in proportion to its breadth than it was before, although it still continues to be a little more broad than thick. During the first two months of pregnancy the uterus gradually descends a little in the pelvis, so that its orifice is more easily perceived with the finger introduced into the vagina ; but at three months it begins to reascend, and also changes its direction, its base goes farther forward, and its orifice backward. These changes increase so much, as pregnancy advances, that it becomes more and more difficult to reach the os tincæ, and more so as the lower part of the anterior wall of the uterus is crowded from above downward, before it, by the lower part, the head of the child. In most cases, in proportion as the uterus is developed, its base rises, and becomes evident through the distended integuments of the abdomen. The anterior face of the organ, especially in the latter months of pregnancy, is situated directly behind the anterior wall of the abdominal cavity. It pushes the small intestine upward, backward, and on the sides ; at least this intestine very rarely descends between the uterus and the anterior wall of the abdomen,(l) and this case probably never happens at the end of gestation. Its volume returns gradually, and even during the first few weeks, to the size it had before pregnancy ; its vessels contract, and at the same time its loose and lamellar structure disappears. It however always remains larger and softer than in a female who has never borne children. It begins to diminish much and to become harder only at an advanced age. The orifice of the vagina, which in the latter period of pregnancy had become a rounded opening, resumes its ancient form : but it is generally torn more or less deeply, whence it is uneven and corrugated. The lips, particularly the posterior, are thicker and longer. They are adapted to each other less exactly. § 2565. The first origin of the new organism is very obscure. We do not know whether the fluid secreted in the yellow body directly assumes any form, so that the ovary furnishes a vesicle filled with liquid, which is the first trace of the ovum or of the envelops ( involucra , s. membranoe) of the fetus : or if this change takes place only in the tube, perhaps even in the uterus. The possibility of the development of the new organism in the ovary does not prove that the fluid of the vesicles is changed there in the normal state; we ought only to conclude that when this fluid does not arrive in the uterus it may assume in every other part the form of an ovum. It is very doubtful(2) whether the ova, discovered in the Fallopian tubes, (3) of animals, were really %hat they were supposed to be, and more so because other observations render another mode of development probable, and particularly that the ovum takes its form in the uterus. (4) But there is a rounded vesicle, composed of several membranes adapted to one another, and containing different fluids, constantly formed before the fetus. The fetus is developed within the ovum, which connects it wfith the organism of the mother. As the human ovum is generally ruptured at its lower part at the period of parturition, and the infant is delivered before it, it is termed the secundines ( secundo: , s. secundinu). (1) Beside the works cited above, which treat also of the changes in the genital organs, consult : T. Kerkring, Anthropogenia, Amsterdam, 1670. — M. Schurig, Embryologia, Dresden, 1732. — F. G. Danz Grundriss der Zergliederungskunde des ungebornen Kindes , Frankfurt, 1792-1793. — C. F. Burdach, De primis momentis formationis fœtus, Königsberg, 1814. — O. C. Lucæ, Grundriss der Entwieklungsgeschichtc des menschlichen Körpers, Marburg, 1819. — Beclard, Embryologie, ou Essai anatomique sur le fœtus humain, Paris, 1820. I. ENVELOPS OF THE FETUS. § 2566. The membranes of the ovum(l) are much larger and heavier the farther the fetus is from the period of its formation. Taken with the fluid they contain, they are at first much heavier than the fetus, and they even weigh more than it at the end of the third month, after being emptied, although the disproportion is then less, as may easily be conceived. At the end of the third month, that is, after about the first third of fetal existence, their weight is nearly equal. After this period an inverse relation exists, so that the mean weight of the membranes of the ovum is to that of the fetus as 1 : 8, since a well grown fetus weighs about eight pounds, and the weight of the secundines, including that of the cord, weighs rather more than one pound. (If Beaide the works already mentioned, particularly those of Nortwyck, Sandifort, and Hunter, consult : A. Vater, Mus. anat. propr., tab. viii. Wittemberg, 1701. — Ruyscb, Thés, anat., VI. tab. i. and ii.— G. Vater, Mola prœgnans, with a plate. — O. Borrich, Abortus humanus examinatus ; in the Act. Hafn., vol. ii. p. 49. — B. S. Albinus, De vasis placentae parvulorum embryonum et de involucro, quo édita eorum ova continentur ; in the Annot. acad., lib. i-xvii. — Id., Nonnulla de embryonibus humanis ovisque, quibus continentur, ibid., xix. — P. A. Boehmer, Instil, osteol., Halle, 1751, tab. i. f. 7, 8.— D. C. Burdach, De lœsione partium fœtus nutritioni insertiontium abortus causa, Leipsic, 1768. — E. Sandifort, De ovo humano, absque ullo fœtus indicio, et placentœ in hydatides degeneratione ; in the Obs. anat. path., book ii-iii. p. 76. — Id., De ovo humano , ibid., book iii-vi. p. 91. — Blumenbach, Institutiones phys., 1787, tab. iv. — S. T. Sœmmerring, Icônes embryonum humanorum, Frankfort, 1799. — Denman, Practice of midwifery, London, 1801, tab. vi-viii. — Wrisberg, Obs. anat. obst. de structura ovi et secundinarum humanarum in partu naturali et per fecto collectas, Gottingen, 1782. — C. G. Krummacher, Diss. sistens observationes quasd. anat. circa velamenta ovihumani, Duisburg, 1790. — J. F. Lobstein, Essai sur la nutrition du fœtus, Strasburg, 1802. — Samuel, De ovorum mammalium vêlamentis, Wurzburg, 1816. — Dutrochet, Recherches sur les enveloppes du fœtus ; in the Mém. de la soc. méd. d’émul., vol. viii., 1817, p. 1-60. — G. Cuvier, in the Mém. du Museum , vol. iii. — Dutrochet, Observ. sur la structure de l’œuf des mammifères et examen de la doctrine de Cuvier sur cette matière ; ibid., p. 760-767. — Dutrochet, Mém. sur les enveloppes du fœtus ; in the Journ. compl. du Diet, des sc. méd., vol. v. p. 241. — Velpeau, Sur les membranes du fœtus ; in the Archiv, gén. de méd., November and December, 1824. (2) Haller, Elem. phys., vol. viii. p. 183. — Osiander, Handbuch der Entbindungskunde, pt. i. p. 191. — F. J. Moreau, Essai sur la disposition de la membrane caduque, sa structure et ses usages , Paris, 1814. It is entirely different from the other membranes, is thicker, more opaque, but infinitely less solid. It has about the consistence of coagulated fibrine, which it also resembles in its yellowish color. Its thickness is not the same in all parts of its extent. It is generally thicker in the region of the placenta, and smaller at the lower part, opposite the internal orifice of the uterus, than in any other point. It always diminishes from the moment of its origin, so that finally it is scarcely half a line thick. Its external face is at first uneven and corrugated ; but in time it becomes smoother, as is- already its internal face. The connections which unite it to the uterus are much looser in the early periods than at the end of pregnancy. In fact, beside the portion of this membrane which unites it by its external face to the internal face of the uterus, there is a second which is reflected on the preceding, and is contained within it. This second layer is attached by its inner face to the chorion, and is loose on its external face, while the other fold is loose on its internal face, and adheres to the uterus by the external. The first fold of the membrane is called the external or true deciduous membrane (AI. decidua externa, s. vera) : the other is termed the internal or reflected deciduous membrane (AI. decidua interna , s. reflexa ) ; it has also very improperly been termed the fungous deciduous membrane (chorium fungosum). The arrangement of the deciduous membrane however differs from that of the serous membranes, because the external fold is not only reflected upon the chorion, but also on leaving this point, where it is inflected, it is extended on the latter, which it consequently envelops in every part.(l ) (1) Moreau (he. cit., p. 16) rloes not assent to this opinion. When the ovum is separated from the uterus it seems in fact enveloped in every part by the deciduous membrane : but according- to him, as the flocculent tissue which covers the placenta at the third or fourth month of pregnancy does not exist in the first, and as from the fifth to the seventh month it is changed into a real cellular tissue, to form the uterine portion of the placenta, into which the vessels of the fetus open with the uterine veins, we must consider it a tissue of secondary formation, similar to the deciduous membrane, with which it i* continuous, and not as a part or appendage of this membrane. F. T. The reflected deciduous membrane particularly is thin and reticulated, and it is much thinner than the chorion. It likewise becomes much thinner ns the ovum enlarges. It also approaches the external deciduous membrane, to which it is finally more or less adherent. § 2569. The external deciduous membrane never extends beyond the internal orifice of the uterus. On leaving this point the uterus or the neck is filled only with a gelatinous fluid. According to some observers the external deciduous membrane extends to a certain extent in the tubes, especially on the side where the yellow body is formed, (1) and it isopen at the place of the uterine orifices of the tubes, as also at its lower part, that which passes on the inner orifice of the uterus. (2) Perhaps these openings exist at first, but the membrane seems to change very soon into a perfectly closed sac, since the lower opening does not exist during the first month, (3) and the upper'two are also effaced at the second. (4) § 2570. It is not very easy to explain how the reflected deciduous membrane is formed. Most probably the ovum, or the fluid from which it is produced, penetrates into the substance of the deciduous membrane, which is always very soft and very loose, but which presents these characters primitively, the spaces resulting from them afterwards close, and the ovum is then developed in the cavity of the membrane. (5) This theory agrees with the observations from which it has been concluded that the external and internal deciduous membranes are primitively distinct, that the external appears first, on leaving the base of the uterus, as a membrane possessing longitudinal blood-vessels, and consequently composed apparently of bands which have the same direction, and that the internal is developed afterward, on leaving the inner face of the preceding, and possesses horizontal vessels : so that the ovum on arriving at the uterus falls into a cavity, the roof and parietes of which are formed by the external deciduous membrane, while the floor is constituted by the reflected deciduous membrane. (6) (5) Moreau asserts that when the ovule enters the uterus through the Fallopian tube, it only pushes before it the deciduous membrane, which is already a little organized before its arrival ; that it is covered, as is every internal viscus, by the serous membrane of the sphlancnic cavity in which it is situated; that this keeps it in contact with that portion of the uterus to which it is attached ; that it is reflected on it on leaving the place where the placenta is formed, and which is the only part not covered by it ; that the three openings admitted by Hunter do not exist : in a word, that the deciduous membrane is arranged exactly like the serous membranes. This theory is more probable than the ancient, and has been developed by Velpeau, who supports it by the observation and dissection of a dozen human ova. F. T. At least it follows from these same observations that the ovum is not introduced into the substance of the deciduous membrane at the same period as when this membrane is developed on the inner face of the utevus,(l) since the phenomena mentioned by us have been observed in the cases where the ova are still contained in the tubes. (2) § 2571. Notwithstanding its early appearance, the deciduous membrane does not belong to the fetus, and is not indispensable for its development, since it also forms equally in the uterus in cases of extrauterine fetation, and the fetus then is not the less developed, although destitute of it. (3) § 2572. The ovum, on the contrary, includes other parts which are essentially connected with the formation of the fetus. These parts are the chorion, the amnios, the umbilical vesicle, and the allantoid membrane, which we proceed to describe, without regard to the order in which they form, nor the part they take in the special vitality of the fetus. I. CHORION. § 2573. The chorion ( chorion , s. chorion pellucidum, s. JYI. vasculosa, s. extima ), the most external of the special membranes of the ovum, is thin, transparent, and villous on its two faces, particularly the external. The villosities of this latter are much longer than those of the internal and ramify. Notwithstanding its thinness and transparency, the chorion is formed of two layers, an internal and an external, between which wind small vascular trunks communicating with the villosities, and which arise from them. (5) Velpeau. He thinks that the chorion is always formed by a single layer, and if it is cccisidered to be formed by two, it is only because rather a thick membranous concretion forms between it and the placenta when this latter is developed, which may be separated into several layers. As the placenta is developed on the outside of the chorion, the same anatomist also states that it covers the fetal face of this organ, and is even reflected on the cord, with which it arrives at the umbilicus, where it blends/ with the skin of the fetus. F. T. membrane, and by the internal with the amnios. Although there may be on its external face only a great development of vessels, we cannot, however, demonstrate the existence of these latter in its substance. In fact many observers have admitted them, and even very recently it has been adduced in favor of their existence that the deciduous membrane contains so many of them, because, they say, these last must penetrate into the chorion ; and the vessels of the deciduous membrane seem to us to have with those of the chorion a relation similar to that between the vessels of the uterine portion and those of the fetal portion of the placenta, and in this hypothesis we can easily conceive of the great vascularity of the deciduous membrane. The chorion has no lymphatic vessels or nerves. § 2574. Its form and connections vary much at different periods of the life of the fetus. It is proportionally much thicker at first than it is subsequently: it is thicker than even the anmios, but gradually becomes thinner. Its external face is villous in every part, and these villosities are at first longer than they are afterward and in the second month are tortuous and proportionally longer than before.. But after the third month these villosities gradually disappear in most of its extent, usually from below upward, so that the outer face of the membrane is finally almost smooth, and the portion which surrounds the insertion of the umbilical cord is the only one where we still observe the villosities compactly arranged, and uniting to form the cord. This place forms with the deciduous membrane a rounded mass, which in the full-grown fetus occupies about the third of the circumference of the ovum, and is termed the placenta. in other parts. At first this membrane is united to the deciduous membrane more loosely than it is subsequently ; but it is gradually attached to it so intimately that they are separated with difficulty, particularly on the circumference of the placenta, where the union occurs by numerous filaments, remnants of vascular villosities, with which its whole surface is at first covered. § 2575. The amnios ( amnion , s. tunica ovi intima ) is a very thin and transparent membrane, which directly envelops the fetus. Its external face adheres but feebly to the chorion, except where it covers the inner face of the placenta : the internal, on the contrary, is loose. These two faces are perfectly smooth, excepting always some very loose cellular tissue which covers the external. Often and perhaps even always during the early periods of pregnancy, this membrane is more or less separated from the chorion, which is much more extensive, and between them is a fluid termed the false waters of the amnios ( liquor amnii spurius ). But this liquid disappears early, at the second montb,(l) when the two membranes touch, although they are sometimes separated at the fourth and fifth months. (2) The amnios is reflected on itself at the origin of the umbilical cord, covers the umbilical vessels, of which it forms the external envelope on the sheath, and extends to the anterior face of the abdomen, where it is continuous with the projecting portion of the skin of this region which forms the umbilicus. As yet neither blood vessels nor nerves have been found in the amnion, although very probably the substance which serves to unite it with the chorion contains the passages through which the nutritious and secretory fluid penetrates to it. § 2576. This membrane contains a liquid termed the waters of the amnios ( liquor amnii), (3) which varies in several respects at different periods of the life of the fetus. In regard to its physical qualities it is limpid and more or less transparent in the early periods of pregnancy ; but at the end it becomes turbid and more or less flocculent. It is also at first thinner and less viscous. Its specific gravity is a little less than that of water. Its absolute and relative quantities vary at different periods of pregnancy. The nearer the fetus is to its period of formation, the more abundant proportionally the waters of the amnios. (3) Franck, De liquore amnii, Gottingen, 1764. — F. A. Koenig, De aquis ex utero gravidarum et parturientium profluentibus, Halle, 1769. — J. P. Hettler, De liquoris amnii natura ac indole, Giessen, 1776. — H. Van den Bosch, De nalurâ ét utilitale liquoris amnii, Utrecht, 1792. — P. Scheel, Diss. de liquoris amnii arteriæ aspcrœ fœtuum humanorum naturâ et usu, cui adjeclus est appendix sistens gencraliora qucedam de liquore amnii, Copenhagen, 1799. — Bunivaand Vauquelin, Expériences sur les eaux de V amnios ; in the Ann. de chimie, vol. xxxiii., and Mém. de la soc. méd. d’ém., vol. iii. p. 229. — F. F. Reuss and F. A. F.mmert, Chemische Untersuchung des Fruchtwassers aus dem zeitigen Ei und der käsigen Materie auf der Haut der neugebornen Kinder: in Osiander, Annalen , Gottingen, 1801, vo). ii. p. 107. — G. Egeling, De liquore amnii, nee non positiones mcdici argumerti, Leyden, 1813. — G. F. Fuckel, De liquoris amnii in fœtus corporis superficial! pressions , Marburg, 1819. fetus. From this period they gradually diminish, so that even when the fetus is delivered without breaking the membranes, they do not weigh more than a pound, and in common parturition not more than eight ounces. Their absolute like their relative quantity increases at first, but afterwards diminishes. Thus, for instance, we find only thirty-six ounces from the third to the fourth month. In regard to chemical composition it is to be regretted that the waters of the amnios in the female have not yet been analyzed, nor comparative experiments made, which however are not difficult, in animals at different periods of gestation. All those we possess were made on the waters received at the moment of parturition, that is, in the latter periods of pregnancy. According to Scheel the waters of the amnios contain free oxygen ; but the analyses of it made since(l) have not confirmed this assertion.^) We find in it no traces of loose alkali. The fluid portion is composed of a considerable quantity of water, a little albumen, a still smaller proportion of gelatine, of the hydrochlorates of ammonia and soda, and of phosphate of lime. Heat, alcohol, and acids do not change. it, or but very slightly. Some think that the waters of the amnios are formed by the fetus and others by the mother. The first represent it as an excretion, and the second as a nutritious substance. others that it is exhaled by the skin. Many(4) suppose that its composition is mixed, especially in the latter periods of pregnancy, that it is formed partly of the excretion of the fetus, partly also by a nutritious substance. The most probable opinion is, that the waters of the amnios are secreted at least in great part by the vessels of the mother, although at the end of pregnancy they are furnished partly by the fetus. We have been led to this opinion because it seems infinitely probable that this liquid serves for the nutrition of the fetus. In fact : cohol,(l) we can explain this difference by admitting that the nutritious substance has been absorbed at first, and that when it is less abundant it has been replaced by another mode of nutrition. 2d. The waters of the amnios are probably absorbed by the skin ; for after tying a ligature around the limbs of a fetus plunged into this liquid, the sub-cutaneous lymphatics soon swelled, while those of the limbs which were not tied were empty. (2) Secondly, fetuses have been born with the mouth closed, and with an umbilical cord entirely separated from the placenta, closed and rounded at its loose extremity.^) 3d. The amniotic fluid also penetrates through the mouth, since it has been found in the stomach, esophagus, cavity of the tympanum, and trachea, where it has been easily recognized both by its physical properties, (4) as by the silky «hairs of the child, and also the meconium.(5) 4th. They moderate the pressure of the fetus on the uterus. But they do not serve, as has been said, to prevent the obliteration of the openings and the cavities of the body :(8) first, because we not unfrequently find such anomalies ; second, because the mucous membranes have no tendency to adhere, at least unless alterations in texture supervene in them. The observations of abnormal anuses, which continued open for many years, proves also that these secrete fluids enough to prevent the union of their surfaces. A. PLACENTA. § 2577. The placenta(l) is generally a rounded, oblong, soft, but solid mass, particularly at its circumference, and is composed of the chorion and the deciduous membrane. It is the most vascular part of the ovum, that by which it is attached most intimately to the uterus. This body is generally eight inches long in its greatest diameter, six in the smallest, and one thick ; but it gradually becomes thinner towards the circumference. Its thickest portion is where the umbilical cord is detached from it. It is generally inserted, especially in the first pregnancy, at the upper and posterior part of the uterus, a little to the right. None of the mechanical explanations of this phenomenon are satisfactory.(2) The placenta is composed of a considerable number of lobes ( colyle dones ), which vary in size, and are rounded and irregular in form ; they are particularly apparent on its outer or uterine face, and render it very uneven. About the period when the fetus is full-grown, it is covered at its outer face by a layer very similar to the deciduous membrane, which extends not merely from one lobe to another, but penetrates between them and unites very intimately with the vessels of the placenta. These last communicate with those of the uterus. Between them and the placenta are very large veins. We remark particularly on the circumference of the placenta a circular vein, into which several veins of the deciduous membrane open. Although this layer is similar in structure to the deciduous membrane, it seems however to form afterward, since the portion of this latter which corresponds to the placenta disappears soon after its union with the uterus, and the layer in question exists only during the latter half of pregnancy. (3) of the ovum, since the vessels of the chorion are mostly’and gradually obliterated. Even a part of those of the placenta gradually close, and then appear so many cords filled here and there with phosphate of lime, particularly towards the upper face of the organ. This deposit occurs also out of the vessels. It is a sign of maturity, of old age, of the mortification of placenta, and it is therefore observed only when the latter is about to be detached. The maturity of the placenta is indicated by its receiving fewer vessels ; it becomes dryer, and even diminishes in its mass and size,(l) although these changes are much less evident in the female than in the females of animals. (2) We must then consider them as a commencement of separation between the organism of the child and that of the mother, as a prelude to parturition. Hence why it is then much larger than it is subsequently. At first until the second month, sometimes even later than this, but then an anomaly exists, the umbilical vesicles are straight. They gradually become more or less tortuous, and the cord also assumes this appearance, the more so as its caliber also diminishes. It is curious that these inflexions generally take place in the same direction, from left to right, which occurs nine times to one, judging from our observations. We may inject this gelatinous substance(l) with mercury by compressing it a long time ; but we cannot conclude certainly from this that it receives special vessels for transmitting a fluid from the placenta into the body of the fetus. We can at most conclude from this experiment that the gelatine of Wharton is composed of tunnels adapted one to another, formed by cellular tissue, and containing a substance in motion which probably serves to nourish the fetus. (2) Although different ancient and modern anatomists assert they have discovered some lymphatic vessels in the umbilical cord, (3) neither Lobstein nor myself(4) have perceived them, notwithstanding all our researches on this subject. § 2579. The umbilical cord does not generally arise from the centre of the placenta, but is inserted a greater or less distance from its edge. It is attached to the anterior face of the abdomen, as much lower, the younger the fetus is, and on leaving this part its constituent portions separate. fetus rests directly on the amnios. When it once begins to appear, it extends continually until the fetus is matured, so that it is generally about two feet in length at this time, and hence nearly as long as the full-grown fetus. We must however remark that these two periods are generally separated by a third, during which the umbilical cord is proportionally longer, and exceeds more or less that of the fetus ; this occurs at least from the end of the second to the end of the sixth month. § 2580. The placenta and the umbilical cord establish the communication between the child and the mother. The first is essentially composed of two different parts, the fetal and the uterine portion. glionnary nerves of the fetus along the umbilical vessels into the placenta. (Chaussier, Expériences nouvelles sur le digestion , et’remarques ace sujet; in the Journ. univ. des sc. méd., vol. i. p. 233.) F- T. The fetal portion is formed by ramifications of the umbilical vessels and by the chorion ; the uterine by the prolongations of the uterine vessels and by the deciduous membrane. These two portions are united much more intimately the older the fetus is ; but their respective vessels always remain separate, so that the arteries and veins of the uterine portion communicate directly, as do those of the fetal placenta. Hence why injections of the uterine vessels, even when most successful, fill only the uterine placenta, while those through the umbilical vessels fill only the fetal portion. Hence also when we inject the placenta detached from the body, or when it is not separated from the body of the living infant, so that the blood circulates uninterruptedly within it, there is no dribbling of blood from its loose surface. Hence the pulses of the mother and the umbilical cord are not isochronous. This explains why children born without the rupture of their envelops can live a greater or less length of time, the circulation continuing perfectly/ 1 ) and probably only the change of temperature obliges us to open all the envelops, although Wrisberg has prolonged the experiment for nine minutes, and Osiander for a quarter of an hour The same fact explains why the cord, which remains for a long time in communication with the mother, after being separated from the body of the fetus, presents only a slight running, produced by the small quantity of blood contained in the fetal placenta. Finally why fetuses can survive not only several hours when their mother perishes from hemorrhage, but can also preserve more or less the quantity of blood they generally possess. § 2581. The internal or fetal placenta is composed only of numberless ramifications of the umbilical arteries and vein, surrounded by a vaginal prolongation of the chorion. The arteries and the veins always proceed together and are very much curved, like the trunks ; their final ramifications even accompany each other constantly, so that we find a small artery and vein inclosed in the same vaginal prolongaion of the chorion. This arrangement however occurs only in the latter periods of pregnancy ; for during the early stages, the vessels of the fetal placenta are single and only venous, like those of the chorion in general. Besides these vessels, we find in the placenta white tendinous filaments which arise from the chorion, enter with it between the vascular trunks, and seem to be only obliterated vessels, which are often half open and receive injections. If we except a considerable and oblique anastomosis between the two umbilical arteries at the base of the placenta, their subordinate branches do not communicate from one lobe to another within this body. There is no other anastomosis between the branches of the (1) In the experiments of Rœderer, Wrisberg-, and Osiander (Rœderer, De vi imaginationisinfœtumnegandâ, Gottingen, 1756. — Wrisberg, Obs. de struct, ovi ; in the Comment., vol. i. p. 618. — Osiander, Annalen, vol. i. pt. i. p. 27-28), which we have repeated with the same results on dogs, cats, and rabbits. monstrate in it the existence of nervous filaments. § 2582. The uterine or external portion of the placenta is much firmer than the internal, and formed by the membrane similar to the deciduous membrane mentioned by us above. This membrane covers its outer face, and gives it a warty appearance ; but at the same time it sends internally numerous irregular prolongations, which penetrate between the most minute ramifications of the umbilical vessels, with which they form alternate elevations and depressions. of the uterine vessels. The arteries are very tortuous, and the diameter of the largest is nearly a line. The veins, which are less tortuous, but which go obliquely to the placenta, are infinitely broader. Numerous ramifications of veins arise from the deciduous membrane, which, after uniting in trunks, are distributed principally on the edge of the placenta. The arteries and veins communicate in the uterine placenta, not by anastomoses, but by large cellules which may be completely filled, either through the venous or arterial trunks, and in which the injection is always effused before passing from the arteries into the veins. islands. § 2583. Notwithstanding the separation of the two circulations in the placenta, there is, however, between its two constituent portions and their vessels a relation of mutual action, which may be compared to that existing between the air and the blood in the lungs, or between the food and the chyliferous vessels in the intestinal canal. § 2584. The uterine placenta is only a transient production, of which the uterus is in great part disencumbered when the fetal placenta is expelled, although a portion of the deciduous membrane is not perfectly detached from the inner face of the organ until several days after delivery. From this intimate connection between the uterine placenta and the uterus, although the section of the cord occasions only a slight and momentary flow of blood, as we have said above, there is, on the contrary, a greater or less hemorrhage from the rupture of its vessels when this portion is detached, which is soon stopped by the contraction of the uterus. IV. UMBILICAL VESICLE AND ALLANTOID MEMBRANE. § 2585. Beside the membranes hitherto mentioned, the existence of which is certain, there are two not so generally admitted, but which are similar in form and situation, but differ from the two preceding in these two respects. They are the umbilical vesicle and the allantoid membrane. These two membranes do not form superimposed sacs and envelops of the fetus, but are situated between the chorion and the amnios. They do not continue as long as the other two membranes, since they disappear, or at least become inactive, at the third month of pregnancy. They however cannot be confounded with each other, nor can we suppose, with Lobstein, for instance, (1) that the umbilical vesicle of man is the allantoid membrane of animals. They are two entirely different organs, which coexist in most vertebrated animals, and apparently in man also. § 2586. The umbilical vesicle ( V. umbilicalis , s. saccus vitellarius, s. vesica vitellaria, s. intestinalis , s. processus infundibuliformis , s. hydatis funiculi) is constant. Although Osiander has asserted that it should be considered as a pathological phenomenon, occurring only in monstrosities, (2) it really exists in every ovum during the early months of pregnancy. The umbilical vesicle of man corresponds neither to the allantoid membrane of the mammalia(3) nor of birds : for the arguments drawn from its constancy, transparency, the clear and limpid fluid which fills it, its situation between the other membranes of the ovum, and the existence of vessels on its surface, adduced in favor of this comparison, are so many circumstances which demonstrate still better its analogy with the umbilical vesicle of the mammalia, and the vitelline sac of birds. The nature of its vessels and its connections with the intestinal canal also support this analogy. Besides as the allantoid membrane is independent of it in the mammalia and in birds, and probably also in man, Lobstein’s opinion cannot be admitted. § 2587. This vesicle is as much larger proportionally as the fetus is younger, and it at first probably exceeds it in size ; at least Lobstein has figured a case of this kind, (4) and we have one almost similar before this agrees with the dimensions given by most authors, § 2588. This organ is at first situated directly against the anterior face of the fetus ;(1) but it removes from it after the end of the first month, and is then situated on the outside of the umbilical sheath. § 2589. We know nothing certain in regard to the period when the umbilical vesicle appears. Judging from analogy with birds, as it corresponds to the vitelline sac, we might conclude that it arises before all other parts of the ovum, and on this account it has even been asserted that the false germs are umbilical vesicles, and not sacs formed by the chorion and amnios, as is generally supposed.(2) Although the received opinion be not perhaps applicable to all cases, we however shall continue to follow it until the contrary is proved by positive facts. According to Hunter, (3) the umbilical vesicle sometimes continues to the end of pregnancy ; but it is not larger at this period than in an ovum of two or three months, and is from half an inch to an inch and a half distant from the insertion of the umbilical cord in the placenta. We regard this fact as very rare, having found it only twice in a great number of deliveries. § 2590. The umbilical vesicle is formed by rather a thick granular membrane, which does not tear when forcibly distended with water. (4) It gradually collapses, is covered with wrinkles, and becomes opaque. The omphalo-mesenteric vessels are distributed in it. thick, and finally hardens. § 2591. We have treated of its connections with the fetus at some length in the histoty of the development of the intestinal canal, and we have attempted to demonstrate that very probably it communicates with the ileon by the omphalo-mesenteric vessels and by a canal. § 2592. Its constancy, its great size in the commencement, and its probable existence before other parts, prove that it takes a very important part in the development of the fetus. Judging from what occurs in birds, its contents pass into the body of the fetus, and serve for nourishment, like yolk to the chicken. It however disappears sooner than the vitelline sac. Needham, (2) Hale, (3) Bidloo,(4) Hoboken, (5) de Graaf,(6) Littré, (7) Rouhault,(8) Neufville,(9) Haller, (10) Emmert,(ll) Joerg,(12) Dutrochet.,(13) and Cuvier, (14) admit it. Paré, (15) Harvey,(16) Ruysch.(17) Heister, (18) Troortwyk,(19) Neu, (20) Albinus,(21) A. Monro, (22) Danz,(23) and Hunter, (24) deny it. Although some of the numerous facts adduced to support it are false, and others but slightly conclusive, we however agree with the first of these two opinions, because we have found in a human fetus about four weeks old, between the chorion and the amnios, and independent of the umbilical vesicle, a larger pouch, with thin parietes, collapsed, and containing a limpid fluid. (25) We have seen this since. Its existence may be supported : 1st. By the cases where we have found in the other membranes a pouch different from the umbilical vesicle. In fact some observations of this kind are very suspicious ; but we have several times been satisfied of the existence of a delicate layer, differing from the rest of the ovum, which first forms a close vesicle until about the end of the second month of pregnancy, and which afterward appears as a thin lamina. is greater in the early periods than afterward, and is filled by a fluid (1) R. Hale, The human allantoid discovered ; in the Phil, trans., p. 270, — Sellius, De allantoide , Kiel, 1729. — C. de Neufville, De allantoide humanâ, Leyden, 1736. — Haller, De allantoide, 1739. — J. G. Betschler, Diss. num a fœtu urina secer » natur et sécréta excernalur, Berlin, 1820. than those of the other membranes. Tt is not certain that it communicates at any period with the urachus. Dutrochet admits this communication, but has never observed it. It however probably exists, at least in the early periods of gestation, either from analogy, or because the urachus makes part of the umbilical cord, or finally from the possibility of following it there more or less to the placenta, (1) of introducing into it a liquid, (2) and even of demonstrating within it an immediate connection between this body and the allantoid membrane. (3) We have been able more or less easily to follow the urachus in almost its whole length at every period of pregnancy, and even to fill it partially wdth mercury : but we have never been able to prove that it communicated either with the space between the two proper membranes, or with the allantoid membrane. This is the opinion of most physiologists and physicians. Joerg thinks even that the allantoid membrane itself secretes urine, (4) which is not very probable, since the kidneys exist, and are more developed than at subsequent periods of life. 3d. Because the allantoid membrane is at first proportionally and even absolutely much larger than subsequently, (10) while it is admitted that the secretion of the urine is in a direct ratio with the advanced age of the fetus. 5th. Because the allantoid membrane is deficient in some mammalia, and it is very improbable that the fetuses of some animals should secrete urine and others not. (2) favor of that of the writers who adduce them. 1st. The existence of the allantoid membrane and its fluid without a fetus proves nothing, and that considered as such may be something else, or the fetus may not be deficient. 2d and 3d. The size of the allantoid membrane and the quantity of its fluid during the early period of gestation, are explained very well by the more rapid progress of all the formations at this period, and because very probably the other excretions do not take place then, or at least but slightly. 4th. The size of the allantoid membrane does not prove that the urinary secretion is the most essential of all the functions, but only that it replaces in great part all the other excretory systems, from the simple reason that the products of the action of these latter had been in contact with the fetus during the whole of pregnancy. for in some way. 6th. In this case the same difficulty exists in passing air from the allantoid membrane into the bladder, (6) while it is very easy during the early periods of gestation, as we have more than once proved. It follows then at most from this fact, that the quantity of urine secreted gradually diminishes, and collects in the bladder. 7th. This objection rests upon confounding the allantoid membrane with the chorion. The vessels do not belong to it, but to this latter ; at least they do not absorb within it, but in the cavity of the uterus. exist in the ova of the batracia. The bladder is not formed by the urachus ;(1) but the canal corresponding to the bladder and urachus, which was at first uniformly narrow, enlarges at its lower part, is completely developed and becomes the bladder, while the upper part, which is not developed in the same manner, remains the urachus. II. ORIGIN OF THE OVUM, AND THE ORDER IN WHICH ITS PARTS FORM. § 2595. It is extremely difficult to determine the period at which the ovum first appears. Although the duration of pregnancy is ascertained with certainty, it does not necessarily follow that the new organism always begins to form at the same period, for the development of the embryos of birds proves that although the ova are all matured at the same period, there is, however, a great difference between embryos of the same brood in the development of different organs, or of the whole body. From the rapidity with which the transitory or permanent parts of the body form successively in the superior animals, and from the proportionally very small number of perfect observations on the development of the ovum in particular, it is extremely difficult to determine if the different parts of this latter, described in the preceding article, form at the same time or at different periods, and also the order of their appearance, and their part in the formation and development of the fetus. Very probably, however, the deciduous membrane begins to form at the same time as the ovum, or the fetal portion of it, since we observe the changes in the uterus, connected with its appearance, very early, even before the latter is seen there. Hitherto physiologists have generally considered the chorion and the amnios as the most essential parts of the ovum, those which arise first ; and even now the external of the two membranes to which the least advanced ova can be reduced is considered the chorion, and the internal as the amnios. Analogy with the development of animals inferior to the mammalia, however, renders it very probable that the umbilical vesicle is developed the first, and that the other membranes form after it, since in the animals mentioned,' the vitelline sac, which corresponds to the umbilical vesicle, appears long before all other parts of the ovum, which precede only the body of the fetus. § 2596. It is very difficult to determine precisely the period when the human fetus(l) forms. This ought not to surprise, for this is still more uncertain in the history of the oviparous animals even, notwithstanding the greater facilities they present to the observer, and the numberless observations upon them. It however is certain that a greater or less length of time elapses after coition, followed by impregnation, before the ovum becomes visible. We may admit generally that it appears in the second week after coition, and there are very probably greater or less differences in this respect. Haller’s(2) opinion, however, that the fetus does not become visible till the end of the third week does not seem to be entirely correct, since it does not agree, among others, with Home’s observation mentioned in the preceding article. § 2597. The problem of the mode of origin of the fetus is still more difficult, and all that has been said on this subject is reduced almost to hypothesis, instead of observations and facts. (1) Beside the works already cited in the course of this book, consult also: 1st. On the form and structure of the fetus: — Cas3ebohm, Dc differentia, fœtus et adulti anatomiccï, Halle, 1730. — C. J. Treu, De jlifferentiis quibusdam inter hominem. nalumet nascendum intercedenlibus, Nuremberg, 1736. — Hebenstreit, Programma de anatomc hominis reccns noli, Leipsic, 1739. — Treu, Descriptio et delineatio embryonum humanorum ; in the Comm. Nor., 1739. — J. G. Rœderer, De fœtuperfecio, Gottingen, 1750. — J. A. Langguth, De anatomice embryonis trium cum dvmidio mensium, Wittembcrg, 1751. — J. G. Rœderer, De fœtu observationes, Gottingen, 1758. — H. A. Wrisberg, Descriptio anatomice embryonis observationibus illustrata, Gottingen, 1764. — A. È. Koelpin, De fœtus et adulti différentiis, Gripswald, 1764. — J. F. Dietz, Differentia fœtus ab adulto, Giessen, 1770. — A. and F. Rosslein, Dedifferentiis inter fœtum et adultum , Strasburg, 1783. — Autenrieth, Supplémenta ad historiam embryonis humani, Tubingen, 1797. — S. T. Sœmmerring, Icônes embryonum, Frankfort, 1799. — 2d. On its mode of existence: — Rose, De natv.râ embryonis humani, Leipsic, 1774. — J. Van Solingen, De vitâfœtàs propriâ , Utrecht, 1782. — A. Brendel, De nutritione fœtîis in utero materno, Wittcmberg, 1704. — Treu, De chylosi fœtûs, Altdorf, 1715. — Bernhardi, De nutritione fœtus in utero, Halle, 1732. — J. de Diest, An sui sanguinis solus opif ex fœtus, Paris, 1725. — A. Nann, Eversa vasorum rubrorum uteri anastomosis et communicatio cum placenta, Erford, 1751.— R. Forsten, Q uœsliones medicœ, Leyden, 1774. — Scha ffer, De commercio fœtûs cum ■maire per nervös, Erlangen, 1775. — Richard, De modo nutritionis fœtûs, Erford, 1783. — Stoy, De nexu inter matrem et fœtum, Halle, 1786. All these arguments are easily refuted. In fact the part first formed has not been strictly determined. It seems probable to us that the rudiment first seen is the common base of several parts, and even in the inferior animals one organ, and in the most inferior the apparently homogeneous substance of their .body represents several organs at the same time. Secondly, we can well conceive that the nervous syrstem appearing first, it is primarily connected with the envelops of the ovum. some portion of the ovum. Finally, another circumstance also exists against this opinion, viz. the membrane of the amnios and the liquid it contains certainly'' appear after the fetus in birds, and the fetus of these animals is connected with the ovum at its first appearance. Judging from analogy with the other vertebrated animals, the human fetus is very probably developed upon the umbilical vesicle, and at its expense. But analogy alone does not merely favor this hypothesis, in support of which we mayr also alledge the greater considerable size of the umbilical vesicle at first, and the position of the lower part of the fetus directly upon this pouch. § 2598. After its origin the fetus presents an almost infinite number of degrees in its form and structure, the most general of which have already been mentioned in the introduction, while-freating of the eight laws of the organic formation, or in descriptive anatomy, in stating inregard to each system and each organ the peculiarities which characterize it at different periods of its development. The portion of its body which appears first, corresponds almost exclusively to the trunk ; we only'- remark at its upper part a small prominence separated from the rest .by a fissure, which is by no means equal in -thickness to the central part of the body. This prominence is the rudiment of the head. dorsal face is slightly convex, and the abdominal slightly concave. It is attached to the inner membrane of the ovum directly, or by a very short umbilical cord at its lower extremity, or by the part of its body directly above this extremity. All the openings which afterward exist are now completely closed. The head gradually becomes proportionally large, so that towards the commencement of the second month it forms nearly half of the whole body. It is generally smaller before and after this period. The body of the fetus curves much at its upper and lower- extremities : the head is continuous with the* trunk at a right angle, and its lower portion, which corresponds with the chin, is attached only to the top of the chest ; the trunk is perfectly straight ; there is no trace of the neck externally until the end of the second month. Until the middle of the third month the lower extremity of the vertebral column is curved from behind forward and from below upward, projects below the anus, and represents the rudiment of a tail, which is at first very long ; this gradually shortens and finally disappears entirety, but it is always attached by its inner face. The limbs appear in the fifth week of pregnancy : the superior generally a little sooner than the inferior. They then have the form of small tubercles terminated by a blunt summit. The superior are situated directly below the head, and the inferior directly before the caudal extremity. Both proceed from behind forward, but a little also from within outward, on account of the greater development of the abdominal cavity. Sometimes also the superior go a little from above downward, and the inferior slightly from below upward, but this arrangement is by no means constant ; they often also, particularly the inferior, assume an entirety opposite arrangement. During the sixth week, and until the seventh, the stump which first appeared and which gradually lengthened, is divided into a peripherical and a central segment : these segments correspond to the hand and fore arm, to the foot and leg. fectly developed. About the period when the stump of the limb begins to divide into an internal and an external part the latter becomes round, and enlarges at its loose extremity, and a single band-like eminence is frequently developed at its summit, from which it is separated by a depression. Thi3 eminence soon gradually divides to form the fingers, which are at first proportionally short and thick, and which until the third month are still united by a thin substance similar to the membrane between the toes of web-footed animals, or the bones of the fins in fishes. from the summit to the base of the fingers and toes. The upper limbs appear before the lower ; they also pass through all their successive degrees of formation more rapidly than the latter. They are for a long time absolutely larger, so that at five years of age the four limbs have nearly the same length. When the limbs appear we begin to see also the external genital organs, the nose, the eyes, the ears, and the mouth, the successive development of which follows the course mentioned when treating of each of these organs. The insertion of the umbilical cord gradually ascends. The umbilicus, however, is still proportionally much nearer the symphysis pubis in the full-grown fetus than in the adult, which difference is directly connected with the gradual diminution of the liver. about six pounds in weight. The increase is very rapid at first, and afterwards is gradually slower. It is asserted that it diminishes at the second month, that it becomes more active in the third month, but especially during the second half of the fourth, that it is evidently most rapid in the centre of pregnancy, and that it consequently becomes slower until the end of pregnancy.(l) This proposition is proved with difficulty, for individual differences may easily lead into error. We may however conceive it to a certain extent, by attributing this slowness to the disappearance of the umbilical vesicle about this period, and that it is not completely replaced by another mode of nutrition. IV. VITAL PHENOMENA. § 2600. At the period of its appearance the fetus never makes part of the organism of the mother. Its relations with the mother are the same as those between the child and the external world. It lives a peculiar life, as is demonstrated by the mode of connection between the two organisms mentioned above. Among the vital phenomena those connected with the formation are developed in the greatest degree, and at the expense of the rest. This is proved by the rapidity with which the fetus increases in weight and volume. But the different functions of nutrition take place precisely in the same manner in all essential respects before and after birth. We have already mentioned the activity of the urinary secretion. The intestinal canal and the skin are also active. § 2601. We find very early in the intestinal canal of the fetus a fluid which has not the same qualities at all periods. Until about the centre of fetal existence this liquid is whitish and mucous : but it afterwards changes to a yellowish green, which is thicker and more viscid. It gradually becomes of a darker color in the large intestine, until finally in the latter periods of pregnancy it has the same qualities in the whole intestinal canal, so as to distend it. It is termed the meconium. It is formed of about two thirds of water, about one third of a peculiar substance, similar to vegetable matter, and of some hundredths of mucus.(l) Opinions vary in regard to the origin of the mec'onium. Some consider it a residuum of the fluid of the amnios swallowed by the fetus ; others think it formed from the secretion of the intestines. Although the fetus very probably swallows and digests the fluid of the amnios, yet as meconium has been found also in the intestines of fetuses destitute of a head and mouth, (2) in a portion of the canal situated below a septum which interrupted the continuity of the tube, (3) in a separate end of the intestine which was closed in every part, in the rudiment of a fetus adhering to another regularly formed fetus, (4) and finally in the intestines of another perfect body, (5) it is clear that the deglutition of the waters of the amnios are not necessary to produce it. If consequently we sometimes find it only above the obstacle, when the intestinal canal is obliterated in any part, (6) we must not conclude from this that the fluid of the amnios has been swallowed, and that the meconium is formed from it, (7) but it follows at most that the secretion takes place principally at the upper part of the alimentary canal. We thus explain the peculiar color of the meconium, which might be attributed to the bile, since the tint of this fluid changes at the same time with it, (8) as we have ascertained, and It, however, remains to be ascertained whether this hypothesis has any foundation, since the authors who describe the cases mentioned by us formally indicate the existence of a yellow matter having the qualities of meconium, and chemical analysis has not proved in it the existence of bile. (2) However this may be, the bile seems to have some part in producing the meconium. In fact in some cases, particularly in that mentioned by Sims, and the subject of which was a child two years old, obliteration might be caused consecutively ; in others, as in that described by Brugmans, some difference is stated between the meconium in that portion of the intestine which communicated with the biliary system and that inclosed in the lower intestine. Thus although the bile is not found in this fluid, it may perhaps contribute to produce it. Possibly also when the liver is deficient the intestinal canal supplies the action of this gland. about the sixth month. Opinions are divided in respect to its origin. Some consider it as a precipitate from the waters of the amnios deposited on the surface of the body of the fetus :(5) others think it is secreted by this latter.(6) (4) Buniva and Vauquelin, Annales de chimie , vol. xxxiii. — Emmert and Reusa Chemischi Untersuchung des Fruchtwassers aus dem zeitigen Ei und der käsigen Materie auf der Haut des neugebornen Kindes ; in Osiander, Annalen vol ii Schulz, loc. cit. (6) Levret, Art des accouchemens , 1766, p. 75. — Schulze, Anweisung zur Hebammenkunt , Hildburgshausen, 1770, p. 49.— Wrisberg, in Rcederer, Eiern, artis obstet., note 37.— Bmmert, loc. cit., p. 134.— Lobstein, loc. cit., p. 99.— Hunter, Anat. des swang. Uterus, p. 96. the umbilical cord present no trace of it. 4th. It is very similar to the substance furnished by the sebaceous glands of the glans penis, and its qualities do not allow it to be regarded as a precipitate from the waters of the amnios. § 2604- The motions of the voluntary muscles are but slight. They generally begin to be felt about the middle of pregnancy, although we cannot conclude from this that they do not occur before, since they may be unperceived on account of the smallness of the fetus, and the abundance of the waters of the amnios. § 2605. The fetus necessarily derives in the body of the mother the materials for its growth, preservation, and its secretions. But here a question presents itself: Are there or not several modes of nutrition ? Different authors, particularly Hippocrates, Aristotle, Galen, Monro,(1) and Danz,(2) admit only one mode of nutrition, and consider the umbilical vein as the only channel through which nutrition comes to the fetus. Others believe in the existence of several other channels, as the skin and the system of the mucous membranes, in a greater or less extent. According to this last hypothesis, the waters of the amnios are the source of nutrition for the fetus. Finally, Oken(2) thinks that the mammae also absorb ; but instead of admitting, as had already been done, (3) that the fetus absorbs the milk secreted by its proper mammae, he asserts that these latter organs absorb only the waters of the amnios, and that the fluid introduced by them is carried by their lymphatic glands into the thymus gland, whence it enters the thoracic canal. Those who maintain several modes of nutrition think that they are brought into use simultaneously or successively. The first opinion has more supporters than the second. and discussed the arguments of each party. § 2606. Those physiologists who think that the materials of nutrition are brought to the fetus through the umbilical vein, rest their opinion upon the following facts : tion of the liquid near the end of pregnancy. 3d. The fetus continues to live and be nourished, although the cord is altered in texture, obliterated, and even entirely separated from the body, the umbilicus being perfectly closed at birth. (4) Needham, De formato fœtu, Loudon, 1C67, p. 79. — Blumenbaeh, Specim., physiolog. comp, inter animalia cal. sang. ovip. et vivip., Gottingen, 1786.— Id., Instit. physiol., p. 449. — Soemmerring, in Haller, Grundriss der Physiologic , 1796, vol. ii. p. 800. — Lobstein, loc. cit. — Emmert, Vcbcr das Nabclblaschen ; in Riel, _4rchiv. für die Physiologic, vol. x. p. 77.— Jocrg, Zeugung, p. 286. 1st. Its nutritious properties. 2d. Its abundance in the early periods of fetal existence, which is connected with the shortness and size of the umbilical cord, since the size of this cord does not depend solely on the presence of a greater number of parts within it. § 2607. Those who admit but one mode of nutrition, particularly that by the umbilical vein, adduce, first the fact that other channels, particularly the absorption of the waters of the amnios by the skin and the mucous membranes, are insufficient ; and secondly that it is indispensably necessary to the life of the fetus for this passage should be open. g. The products of digestion found in the intestinal canal prove nothing, since they may arise solely from the action of this organ, (3) and tho more as meconium also has been found above the point where obliteration had occurred. (4) h. The existence of the meconium and the hairs in the stomach prove nothing, for hairs might be developed in the alimentary canal, and the meconium pass up through the intestines into the stomach. (5) i. We may also consider deglutition and the sucking of the newly born child as valueless, since numerous other phenomena supervene at the period of birth, although the system has made no previous attempts, and the latter had already commenced before parturition by swallowing the waters of the amnios. § 2608. We have now to examine whether all the arguments alledged against the hypothesis that the fetus is. nourished by the fluid of the amnios are sufficient to refute it. Strict inquiry determines that they are not. 1st. It is not proved, and it is not even probable, that the waters of the amnios are formed from the blood of the fetus, since the vessels of the chorion may not necessarily be other than the organs of nutrition, and the fluid of the amnios may be secreted by the uterus. 2d. The slight proportion of nutritious materials proves nothing, because nutrition may be well performed with substances which contain less of it, and also because the fluid of the amnios at first contains more of it ; finally because the greater energy of the formative power in the fetus is a sufficient compensation. 3d. The third and fourth arguments prove at most only that the liquid of the amnios is not the only source of nutrition in the fetus, or that the fetus might exist for some time without it : even this latter circumstance does not follow, for it is not probable that the fluid of the amnios is ever reproduced after it has escaped. (1) Danz, p. 59. — G. J. C. Themelius, Comment, qui nulritionem fœtus in utero per vasa umbilicalia solum fieri, occasione monstri ovilli sine ore et faucibus nati ostenditur, Leipsic, 1751. — Van den Bosch, p. 459. 4th. We cannot apply to several well attested cases of infants being bom with the umbilical cord really obliterated, the too general objection that all those of this kind are not authentic ; the only conclusion however to be drawn from this is, that the fetus can support for some time the interruption of its communications with the uterus through the medium of the cord. 5th. The existence of a great quantity of the liquid of the amnios at the end of pregnancy, is without value, since the absolute quantity of the liquid is generally very much diminished at this period. If it is less in quantity in the latter periods of gestation, the only conclusion to be drawn from this is, that it is then less necessary, which coincides with the hypothesis that it serves for nutrition, as the formative acts have then more power, and also possibly another more efficacious mode of nutrition is then developed. 1st. The vernix caseosa does not exist in the early periods of gestation, that is, v/hen the fluid of the amnios contains most nutrition, and when the formative acts are most rapid. Even when it is seen, it does not form on the skin a uniform layer which covers it so as to prevent absorption. 2d and 3d. There is no proof that the stagnation of the amniotic fluid under the skin is necessary, and of the impossibility of its penetrating farther. This stagnation, on the contrary, is very improbable. clusive : for, 1st. The dissimilarity between the fluid in the stomach and the fluid of the amnios is easily explained by a change in these latter ; farther, we have often remarked a perfect identity between the two fluids. 2d. The impossibility of swallowing without breathing is not demonstrated, and certainly is not a fact. Farther, the fluid of the amnios might enter into all the cavities, without being swallowed. in these experiments the animal was dead. 5th. The penetration of the fluid of the amnios with the trachea is unattended with inconvenience ; . perhaps even it is useful. Farther observation seems to demonstrate that it really occurs. only channel through which nutrition takes place, 7th. The development of the hairs is so rare a phenomenon that the constant existence of these hairs in the meconium should be considered as a very peremptory argument in favor of the introduction of the fluid of the amnios into the alimentary passages, although the presence of the meconium proves nothing. Besides these hairs resemble the silky down of the fejus. 8th. Although we reject, and with reason, the opinion that swallowing of the waters of the amnios would be a kind of prelude to sucking and deglutition, it does not follow that when this liquid is found in the stomach its presence should be regarded as unusual. still continues at least very probable. It is no less difficult to doubt the nutrition by the fluid of the umbilical vesicle and the gelatine of Wharton. We have reason to think that the whitish fluid contained in the placenta constantly passes into the body of the fetus through the umbilical cord. nutrition. We cannot at least deny that the contrary opinion can be maintained, since the facts alledged prove only the necessity of the circulation of the blood in the chorion and placenta, but establish nothing in regard to the function of these parts. Farther, as the fetus is nourished in three other modes, and as it cannot be proved that these three modes are insufficient, we have a right to admit that the circulation of the blood in the placenta by the vessels of tire fetus has not the uses commonly assigned to it, provided always that we mention others which are probable. in any other manner. 2d. The analogy between the pulmonary and placental circulations, the placenta and lungs both receiving the blood, from which the sett) G. F. St. Hilaire (Monstruosités humaines , p. 279) having’ found in the intestinal canal an anomocephalus of real fecal matters, moulded even into lumps in the post-ccecal intestine, was led by this phenomenon to examine the proper nutrition of the fetus. He thinks that the mucus secreted in the alimentary passages, and which is in too great a quantity to be used simply as a lubricating fluid, is the aliment first digested; that it is taken up at first by the digestive organs, then by thechyliferous passages, it is the source of the nutritious fluid, which thus flows constantly into the circulatory system, and which at each passage is gradually animalized. Considered in this manner, the nutrition of the fetus would resemble that of the adult. This hypothesis, in accordance with which the discharge of mucus would be caused by the irritation of the mucous membranes by the bile, is very ingenious, but is improbable. In fact we should be obliged to admit that the alimentary tube acts in two totally different ways in regard to the mucus, one action forming the mucus, the other converting it, changing it into chyle. F. T. (2) Mayow, Duverney, Vallisneri, Cheselden, Hérissant, Bœerhaave, and Jampert, in Haller, Elem. physiol., vol. viii. p. 254. — Eckardt, Q uestio an duæ arteriœumbilicales feetui pulmonum loco inserviunt, Jena, 1761. — E. Darwin, Zoonomie, vol. i. — B. N. G. Sclireger, Defunctione placentae uterinæ, Erlangen, 1795. — Lobstein, loc. cit. — Oken, Der Atmungsprocess des Fötus ; in Lucina , vol. iii. p. 294. Very probably then the blood of the fetus is really changed in the placenta, similarly to what it is in the lungs, and the arterial blood of the mother replaces the circulating medium, which is acted upon by the oxygen. We cannot adduce against this hypothesis that there is no difference in the color of the blood in the umbilical vein and arteries, as several observers worthy of confidence have proved, and as we have satisfied ourselves on several occasions ; for possibly the fetus having but little need of oxygen its blood absorbs but a small quantity, and consequently its color is but slightly changed. Schweighæuser has advanced an opinion directly the opposite of this.(l) He thinks that the function of the placenta is to change that which the umbilical veins bring to it into venous blood, and which does not suffer this change in the body of the fetus, in order to render it proper to secrete the bile and to form the solid parts, particularly the nervous system. But this hypothesis is supported by no fact, but it is opposed by several. Thus nutrition in general, and that of the nervous system particularly, is performed by the arterial blood ; the bile may be formed from this blood. Besides the respiratory function of the placenta is imperfect, and consequently the difference between the blood in the umbilical vein and arteries is almost nothing. We cannot consider that of the vein as pure arterial blood, since it has already circulated very extensively in the upper half of the body. Finally, in the ovum of birds the blood of the umbilical artery is black, and that of the vein is red. through allits pores like the aquatic insects, that it separates the air from thcsurrounding liquids, and that the uterus performs the part of the right ventricle by sending the amniotic fluid into all the integuments of the body. This opinion has been confirmed by Lassaigne’s discovery of a gas very analogous to the atmospheric air in the amniotic fluid. Muller has enlarged upon this (De respirations fœtus commentatio physiologica, Leipsic, 1823). This author thinks that the necessity of respiration of the fetus is to that of the child as 10 : 15, or as 2 : 3. But the placenta also concurs in it as well as the amniotic fluids. The fine experiments of Edwards on the asphyxia of the batracia are naturally connected with this great question, and may contribute to resolve it. F- T. The umbilical vesicle first becomes inactive in the second month of pregnancy. After the first half of gestation, nutrition by the waters of the amnios diminishes much, because the fluid lessens in quantity and nutritious qualities, and the vernix caseosa diminishes absorption by the skin. It would seem then that latterly no other channel exists but the gelatine of Wharton. V. duration of the fetal state, and birth. §2611. The fetal state usually continues ten lunar months. After this period the fetus is born , that is, it is detached from the body of the mother, and enters into a direct relation with the general organism, being now capable of an independent existence. It however is frequently separated before the normal end of gestation ; this is termed abortion (abortus). The union between the two organisms rarely continues too long ; this is termed a late birth (partus tardivus , s. serotinus). ( 1) The fetus cannot survive independent of the mother until the sixth month of gestation : even then it generally dies. (2) It has long been disputed to what extent beyond the common period the birth may be protracted ; and the discussion is not terminated. The possibility of the fact cannot be doubted, and is attested by several authentic instances. We cannot, however, deny that a great many of them related depend on the necessity in order to render them legitimate, of a conception supervening in the mother, after the death of the husband. § 2612. Parturition is accomplished by the contraction of the uterus, aided by that of the abdominal muscles. These contractions commence at the base of the organ, while the slighter fibres of the neck gradually cease to act. Hence the cavity of the uterus shortens and contracts, and consequently all parts of the organ, except the lower, greatly compress the fetus, which escapes through the part which presents the least resistance,, that is, through the dilated orifice of the uterus, whence it passes into the vagina, and then through the external orifice of the genital organs. Usually, about as one thousand times to one, the membranes of the ovum, which enter the first, break before the fetus has left the cavity of the uterus, and most of the fluid of the amnios escapes. After the fetus is expelled the uterus is freed from the ovum, by the contraction of the organ following parturition, which very much diminishes the extent of the surface by which it adheres, and ruptures the vessels which unite the placenta. When the posterior fold is once detached the final contractions of the uterus cause its expulsion. The connections between the ovum and the ftterus are rarely destroyed by the first contractions of the latter, and the child is bom enveloped in its membranes, like the young of the mammalia. This case probably happens only in continued pregnancies. It is normal, on the contrary, in abortion. child. The mammae during pregnancy are changed like the uterus. They enlarge, become more vascular, softer, and looser. Their granulations are more distinct. In a word, they resemble the other glands, the secretory activity of which continues uninterruptedly, while pregnancy assimilates the uterus to the muscles which are constantly in action. it is very imperfect. The human milk, like that of the other females of the mammalia, is decomposed by rest into two parts, one fat and yellowish, the other serous ; the former, or the cream, divides into butter and buttermilk. The cream and the creamy milk both contain a substance analogous to albumen, the caseous substance, of which there is but little in the milk of the female, and it is there softer and less coagulable than in that of other animals. It is coagulated by heat and acids, and thus it may be obtained separately. The serous portion of the milk, when entirely freed from caseous substance, has a sweetish taste, which is owing to the sugar of milk, which abounds in the milk of the female. Many calcareous salts exist in the caseous matter. The slight quantity of this latter and its softness prevents the milk of the female from coagulating, or at least but slightly. It is asserted that its cream does not give butter, which is not true. § 2614. The anomalies in the genital organs connected with coition, pregnancy, and parturition, are less numerous and less worthy of notice than those presented by the new organism. § 2615. An anomaly sometimes occurring in the organs of coition is the continuance of the hymen after copulation, and sometimes after parturition. It deserves attention, as it indicates that the presence of this fold is not a certain sign of virginity, and as it renders parturition difficult, particularly when the hymen is solid. Among the anomalies of the genital organs of the female, of which we have already spoken above, the adhesion of the abdominal extremities of the Fallopian tubes with the adjacent organs, particularly with the anterior and posterior face of the broad ligaments, the uterus, the bladder, the rectum, and the ovaries, and the obliteration of their abdominal orifices, are principally results of coition. These two states are observed particularly in prostitutes, (2) where they are probably produced by the frequent and excessive stimulation of the genital parts. They are also common in sterile females, and should be regarded as the most usual cause of sterility, since they prevent the motion of the tubes, and the entrance of the fluid from the ovaries into the uterus. II. NEW ORGANISM. § 2616. We shall examine here, among the anomalies which may supervene on conception and in the formation of a new organism, only those which affect the whole new being and the ovum particularly, since we have already mentioned the deviations in the formation of the fetus, either generally or particularly, in the several parts of this work. The anomaly is greatest in this case when the ovum is situated out of (1) Wrisberg, De secundinarum humanarum varietate, Gottingen, 1773. — Schæfer, De placentœ uterinœ morbis, Leipsic, 1799. — Michaelis, De placenta humana, anatomice, physiologice et palhologice considerata, Erford, 1782. — Hebenstreit, De funiculi umbilicalis pathologia, Leipsic, 1747. the uterus. This is termed extra-uterine conception or gestation (conceptions. graviditas extra-uterina) .(1) The ovum is then developed ia the ovary, in the abdominal cavity, or in the Fallopian tube. (2) The uterus generally changes as it does in pregnancy ; this organ is enlarged, softens, and a deciduous membrane forms in it. In the cases where it is asserted that the latter did not exist, it had probably already disappeared, or it was developed imperfectly.(3) The ovum is destitute of it. pally in abdominal pregnancy. b. It is dead ; this is more frequent, and causes in the adjacent parts, principally the rectum, the integuments, or the vagina, rarely in the bladder, the formation of an abscess, and is usually discharged through the opening in pieces, more rarely entire. c. Long before the first months of pregnancy have elapsed, and even during its first fifth, the too slightly extensible part in which the fetus is developed is ruptured, and the mother dies from an internal hemorrhage, which termination is observed particularly in pregnancy of the Fallopian tubes. More commonly the situation of the placenta in the uterus varies, being developed, particularly in twin pregnancies, at the lower part of the ovum, on the edge of the orifice of the uterus (placentas prcevia, s. oblata). same parents and the same mothers produce several twins. b. The number of coexisting fetuses is never more than five. We may generally admit that twin pregnancies are to common pregnancies as 1 . 100, triplets as 1 : 1000, and quadruplets as 1 : 50,00060,000. (1) See our Handbuch der pathologischen Anatomic, vol ii. p. 160-180. — J. H. Giessmann, Diss. dc conceptione duplici uterina vimirum ct ovaria uno eodemque temporis momento facta, Marburg’, 1820. — F. F, Susewind, De graviditate ovaria, Berlin, 1820. separated from the tissue of this vise ns by a cyst. This has been observed by Schmitt, Hedrich, Carus, and Breschet. Carus (Zur Lehre von Schwangerschaft und Gebert, Leipsic, 1822) thinks, but wrongly, that in these cases the ovule glides and lodges between the peritoneum and the uterus. F. T. c. Generally in a case of twins or triplets the placentas are united in one, but there are two or three choria, two or three amnia, and two or three umbilical cords, so that the two or three fetuses are entirely separate. When two are situated in the same cavity the intermediate septum has evidently been destroyed. The umbilical vessels usually communicate on the inner face of the placenta by a large transverse anastomosis, which arises at the root of the cord. This anastomosis is rarely deficient. This has been wrongly termed a third placenta.(l) there are numerous fetuses. d. In regard to the fetuses, even when there are but two, one and sometimes both are small and imperfect, often to a great degree, for most monsters which are very abnormal are generally twins. (2) This phenomenon is still more evident when there are more than two fetuses, for then all are generally smaller, and are not nourished as well as usual. Sometimes also the existence of two fetuses causes the death of one of them at a more or less advanced period. e. In a twin pregnancy, and still more in triplets, parturition usually occurs before the regular period of gestation. Generally all the fetuses, and even those which are dead, leave the uterus at the same period. Sometimes, however, one of the two is expelled prematurely, while the second remains until the regular period, and is then born. (3) In some cases, but this is less remarkable, the dead infant is not bom till some days after the other, which is perfectly full grown. (4) The fetuses which coexist in the uterus have generally been produced by the same generative act. They are formed much less commonly by several successive actions ; this constitutes superfeiation ( superfelatio).(5 ) The possibility of this fact is proved, first, by cases where the woman has borne two children of different color, and asserted that she had cohabited with men of different races ; secondly, by those, although they are less authentic in fact, which mention full grown children born at an interval of several weeks, and even several months. (3) J. Chapman, Singular case of expulsion of a blighted fetus and placenta at seren months, a living child still remaining the full period of utero-gestalion ; in the Med. chir. trans., vol. ix. p. 194. (5) J. P. Gravel, Re svpcrfetatioue conjectures, Strasburg1, 1738. — M. Tydeman, l)e superfetatione, Utrecht, 1 783. — T. Roose, De super fetatione nonnulla , Bremen, 1801. — .1. C. Varrentrapp, C'omm. in T. Roose dc superfetatione, Frankfort, 1803. nations are by no means worthless ; superfetation, however, more probably, depends principally on the fact that one coition calls into action several vesicles, which do not arrive at the same degree of vital activity simultaneously, even as in birds a single copulation is sufficient to impregnate a considerable number of yolks, which differ much in respect to their development. Superfetation may also depend, in certain rare cases, on no mechanical cause, but on the fact that the capacity of the genital organs and the whole organism of the female is not unfitted by the first conception for a second during the course of the other ; even as the disposition for contagious diseases, to which generation is so analogous, is commonly lost by the first infection, although a second supervenes in rare cases ; or as one exanthematous affection is generally, but not always, arrested by another. § 2618. The new organism is sometimes destitute of certain parts. The most common anomaly in this case is the absence of the fetus, which undoubtedly depends generally on the fact that this latter has perished sooner or later, since the ovum is commonly formed of all the parts which normally compose it, and we there perceive even more or less evident proofs of the previous existence of a fetus. The placenta is deficient more rarely. In one case of the kind recently described(2) it was asserted that the umbilical cord was attached to the inner face of the ovum in the form of a button. pally to the placenta and the umbilical cord. The placenta is sometimes but proportionally very rarely divided into several lobes (; ■placenta succenturiata ), only two of which generally appear, although there are sometimes seven. One of these lobes is generally larger than the others. This anomaly consists in a suspension of development. We have observed it principally in pregnancy with twins, and we have always been satisfied that authors were mistaken in saying that the umbilical vessels then divided unusually soon. This premature division of the umbilical vessels, even within the membranes of the ovum, is rare : but it is still more so for the vessels to separate on the outside of the body of the child. We must arrange here the knots of the umbilical cords termed true, when they are real,(l) and false , when they consist only in more or less compact circumvolutions of the umbilical vessels. § 2620. The umbilical cord presents anomalies in its extent. Sometimes it is too short, being only four inches in length. Less frequently it is unusually long, being fifty inches in length. Sometimes also it is very thin or lean , which depends on the small quantity of the gelatine of Wharton. In other cases it is unusually fat. Here are referred the change of the vessels of the placenta into larger and smaller vesicles, entirely closed and united by contracted portions, which seem to depend on the permanence and the ultimate development of a state primitively normal. with the uterus or fetus. Sometimes, but rarely, the first are firm. Sometimes the fetus is not connected with the ovum. This phenomenon is not rare in the early periods of gestation, and we may also consider it as the result as well as the cause of the death of the fetus. But authors relate also cases in which this insulation was observed at an advanced age of pregnancy. Here we refer to the observations of Chatton,(3) Stalpart van der Wiel, (4) Rommel, (5) Mason Good, (6) and Osiander.(7) All these facts are not equally authentic. Thus Stalpart van der Wiel did not observe the case mentioned by him until several months after birth ; there was at the time an inversion of the bladder ; the umbilicus was situated too low, and blended with the upper part of the bladder, and seemed to be deficient. branes of the ovum too intimately. Here are referred the cases where the umbilical cord is inserted in an unusual part of the body, and is there attached in a greater or less extent before arriving at the abdominal cavity. (8) § 2622. The principal alterations of texture are, the too great hairiness of the membranes of the ovum, generally attended with their thickening : the development of the new formations in the placenta,(l) or of serous cysts in the cord ; finally, the changes of the whole ovum, termed moles, and which are divided into several classes, according to the different substances which form them. § 2623. Parturition presents numerous anomalies, the causes of which exist in the body of the mother, or in that of the child, or in both. These anomalies become also the source of several of those mentioned when speaking of the genital organs, particularly of different deviations of formations, as lacerations of the uterus, the vagina, adhesion and obliteration of the orifice of the uterus, the vagina, and the vulva, after an injury.	271,898	common-pile/pre_1929_books_filtered	manualofgenerald3183meck	public_library	public_library_1929_dolma-0000.json.gz:1786	https://archive.org/download/manualofgenerald3183meck/manualofgenerald3183meck_djvu.txt
CYgIWdvgpAQDV4pq	English Composition II	19 Introduction to Verbs Identify Verb Types and Their Correct Conjugation From 2002 to 2006, The Centers for Disease Control (CDC) ran a media campaign entitled “Verb: It’s What You Do.” This campaign was designed to help teens get and stay active, but it also provided a helpful soundbite for defining verbs: “It’s what you do.” Verbs are often called the “action” words of language. As we discuss verbs, we will learn that this isn’t always the case, but it is a helpful phrase to remember just what verbs are. Traditionally, verbs are divided into three groups: active verbs (these are “action” words), linking verbs, and helping verbs (these two types of verbs are not “action” words). In this outcome, we’ll discuss all three of these groups. We’ll also learn how verbs work and how they change to suit the needs of a speaker or writer.	189	common-pile/pressbooks_filtered	https://library.achievingthedream.org/odessaenglishcomp2/chapter/introduction-to-verbs/	pressbooks	pressbooks-0000.json.gz:62719	https://library.achievingthedream.org/odessaenglishcomp2/chapter/introduction-to-verbs/
rArnygorcSLBWQ4g	Boundless Statistics for Organizations	5.2 Measures of Relative Standing 5.2: Measures of Relative Standing 5.2.1: Measures of Relative Standing Measures of relative standing can be used to compare values from different data sets, or to compare values within the same data set. Learning Objective Outline how percentiles and quartiles measure relative standing within a data set. Key Takeaways Key Points - The common measures of relative standing or location are quartiles and percentiles. - A percentile is a measure used in statistics indicating the value below which a given percentage of observations in a group of observations fall. - The 25th percentile is also known as the first quartile (Q1), the 50th percentile as the median or second quartile (Q2), and the 75th percentile as the third quartile (Q3). - To calculate quartiles and percentiles, the data must be ordered from smallest to largest. - For very large populations following a normal distribution, percentiles may often be represented by reference to a normal curve plot. - Percentiles represent the area under the normal curve, increasing from left to right. Key Terms - percentile - any of the ninety-nine points that divide an ordered distribution into one hundred parts, each containing one per cent of the population - quartile - any of the three points that divide an ordered distribution into four parts, each containing a quarter of the population Example For runners in a race, a low time means a faster run. The winners in a race have the shortest running times. Is it more desirable to have a finish time with a high or a low percentile when running a race? b. The 20th percentile of run times in a particular race is 5.2 minutes. Write a sentence interpreting the 20th percentile in the context of the situation. c. A bicyclist in the 90th percentile of a bicycle race between two towns completed the race in 1 hour and 12 minutes. Is he among the fastest or slowest cyclists in the race? Write a sentence interpreting the 90th percentile in the context of the situation. SOLUTION a. For runners in a race it is more desirable to have a low percentile for finish time. A low percentile means a short time, which is faster. b. INTERPRETATION: 20% of runners finished the race in 5.2 minutes or less. 80% of runners finished the race in 5.2 minutes or longer. c. He is among the slowest cyclists (90% of cyclists were faster than him. ) INTERPRETATION: 90% of cyclists had a finish time of 1 hour, 12 minutes or less.Only 10% of cyclists had a finish time of 1 hour, 12 minutes or longer. Measures of relative standing, in the statistical sense, can be defined as measures that can be used to compare values from different data sets, or to compare values within the same data set. Quartiles and Percentiles The common measures of relative standing or location are quartiles and percentiles. A percentile is a measure used in statistics indicating the value below which a given percentage of observations in a group of observations fall. For example, the 20th percentile is the value (or score) below which 20 percent of the observations may be found. The term percentile and the related term, percentile rank, are often used in the reporting of scores from norm-referenced tests. For example, if a score is in the 86th percentile, it is higher than 86% of the other scores. The 25th percentile is also known as the first quartile (Q1), the 50th percentile as the median or second quartile (Q2), and the 75th percentile as the third quartile (Q3). To calculate quartiles and percentiles, the data must be ordered from smallest to largest. Recall that quartiles divide ordered data into quarters. Percentiles divide ordered data into hundredths. To score in the 90th percentile of an exam does not mean, necessarily, that you received 90% on a test. It means that 90% of test scores are the same or less than your score and 10% of the test scores are the same or greater than your test score. Percentiles are useful for comparing values. For this reason, universities and colleges use percentiles extensively. Percentiles are mostly used with very large populations. Therefore, if you were to say that 90% of the test scores are less (and not the same or less) than your score, it would be acceptable because removing one particular data value is not significant. For very large populations following a normal distribution, percentiles may often be represented by reference to a normal curve plot. The normal distribution is plotted along an axis scaled to standard deviations, or sigma units. Percentiles represent the area under the normal curve, increasing from left to right. Each standard deviation represents a fixed percentile. Thus, rounding to two decimal places, is the 0.13th percentile, the 2.28th percentile, the 15.87th percentile, 0 the 50th percentile (both the mean and median of the distribution), the 84.13th percentile, the 97.72nd percentile, and the 99.87th percentile. This is known as the 68–95–99.7 rule or the three-sigma rule. Percentile Diagram Representation of the 68–95–99.7 rule. The dark blue zone represents observations within one standard deviation () to either side of the mean (), which accounts for about 68.2% of the population. Two standard deviations from the mean (dark and medium blue) account for about 95.4%, and three standard deviations (dark, medium, and light blue) for about 99.7%. Note that in theory the 0th percentile falls at negative infinity and the 100th percentile at positive infinity; although, in many practical applications, such as test results, natural lower and/or upper limits are enforced. Interpreting Percentiles, Quartiles, and Median A percentile indicates the relative standing of a data value when data are sorted into numerical order, from smallest to largest. % of data values are less than or equal to the th percentile. For example, 15% of data values are less than or equal to the 15th percentile. Low percentiles always correspond to lower data values. High percentiles always correspond to higher data values. A percentile may or may not correspond to a value judgment about whether it is “good” or “bad”. The interpretation of whether a certain percentile is good or bad depends on the context of the situation to which the data applies. In some situations, a low percentile would be considered “good’; in other contexts a high percentile might be considered “good”. In many situations, there is no value judgment that applies. Understanding how to properly interpret percentiles is important not only when describing data, but is also important when calculating probabilities. Guideline: When writing the interpretation of a percentile in the context of the given data, the sentence should contain the following information: - information about the context of the situation being considered, - the data value (value of the variable) that represents the percentile, - the percent of individuals or items with data values below the percentile. - Additionally, you may also choose to state the percent of individuals or items with data values above the percentile. 5.2.2: Median The median is the middle value in distribution when the values are arranged in ascending or descending order. Learning Objective Identify the median in a data set and distinguish it’s properties from other measures of central tendency. Key Takeaways Key Points - The median divides the distribution in half (there are 50% of observations on either side of the median value). In a distribution with an odd number of observations, the median value is the middle value. - When the distribution has an even number of observations, the median value is the mean of the two middle values. - The median is less affected by outliers and skewed data than the mean, and is usually the preferred measure of central tendency when the distribution is not symmetrical. - he median cannot be identified for categorical nominal data, as it cannot be logically ordered. Key Terms - outlier - a value in a statistical sample which does not fit a pattern that describes most other data points; specifically, a value that lies 1.5 IQR beyond the upper or lower quartile - median - the numerical value separating the higher half of a data sample, a population, or a probability distribution, from the lower half A measure of central tendency (also referred to as measures of center or central location) is a summary measure that attempts to describe a whole set of data with a single value that represents the middle or center of its distribution. There are three main measures of central tendency: the mode, the median and the mean . Each of these measures describes a different indication of the typical or central value in the distribution. Central tendency Comparison of mean, median and mode of two log-normal distributions with different skewness. The median is the middle value in distribution when the values are arranged in ascending or descending order. The median divides the distribution in half (there are 50% of observations on either side of the median value). In a distribution with an odd number of observations, the median value is the middle value. Looking at the retirement age distribution (which has 11 observations), the median is the middle value, which is 57 years: 54, 54, 54, 55, 56, 57, 57, 58, 58, 60, 60 When the distribution has an even number of observations, the median value is the mean of the two middle values. In the following distribution, the two middle values are 56 and 57, therefore the median equals 56.5 years: 52, 54, 54, 54, 55, 56, 57, 57, 58, 58, 60, 60 The median is less affected by outliers and skewed data than the mean, and is usually the preferred measure of central tendency when the distribution is not symmetrical. The median cannot be identified for categorical nominal data, as it cannot be logically ordered. 5.2.3: Mode The mode is the most commonly occurring value in a distribution. Learning Objectives Define the mode and explain its limitations. Key Takeaways Key Points - There are some limitations to using the mode. In some distributions, the mode may not reflect the center of the distribution very well. - It is possible for there to be more than one mode for the same distribution of data, (eg bi-modal). The presence of more than one mode can limit the ability of the mode in describing the center or typical value of the distribution because a single value to describe the center cannot be identified. - In some cases, particularly where the data are continuous, the distribution may have no mode at all (i.e. if all values are different). In cases such as these, it may be better to consider using the median or mean, or group the data in to appropriate intervals, and find the modal class. Key Term - skewness - A measure of the asymmetry of the probability distribution of a real-valued random variable; is the third standardized moment, defined as where is the third moment about the mean and is the standard deviation. A measure of central tendency (also referred to as measures of center or central location) is a summary measure that attempts to describe a whole set of data with a single value that represents the middle or center of its distribution. There are three main measures of central tendency: the mode, the median and the mean . Each of these measures describes a different indication of the typical skewness in the distribution. The mode is the most commonly occurring value in a distribution. Consider this dataset showing the retirement age of 11 people, in whole years: 54, 54, 54, 55, 56, 57, 57, 58, 58, 60, 60 The most commonly occurring value is 54, therefore the mode of this distribution is 54 years. The mode has an advantage over the median and the mean as it can be found for both numerical and categorical (non-numerical) data. There are some limitations to using the mode. In some distributions, the mode may not reflect the center of the distribution very well. When the distribution of retirement age is ordered from lowest to highest value, it is easy to see that the center of the distribution is 57 years, but the mode is lower, at 54 years. It is also possible for there to be more than one mode for the same distribution of data, (bi-modal, or multi-modal). The presence of more than one mode can limit the ability of the mode in describing the center or typical value of the distribution because a single value to describe the center cannot be identified. In some cases, particularly where the data are continuous, the distribution may have no mode at all (i.e. if all values are different). In cases such as these, it may be better to consider using the median or mean, or group the data in to appropriate intervals, and find the modal class. Attributions - Measures of Relative Standing - “Susan Dean and Barbara Illowsky, Descriptive Statistics: Measuring the Location of the Data. September 19, 2013.” http://cnx.org/content/m16314/latest/. OpenStax CNX CC BY 3.0. - “David Lane, Percentiles. October 12, 2013.” http://cnx.org/content/m10805/latest/. OpenStax CNX CC BY 3.0. - “Standard deviation diagram.” http://en.wikipedia.org/wiki/File:Standard_deviation_diagram.svg. Wikipedia CC BY. - Median - “Error 404.” http://www.abs.gov.au/websitedbs/a3121120.nsf/89a5f3d8684682b6ca256de4002c809b/3a5b4029ba31b1cbca257949001281f8!OpenDocument. Austrailian Bureau of Statistics CC BY-SA. - “Comparison mean median mode.” http://en.wikipedia.org/wiki/File:Comparison_mean_median_mode.svg. Wikipedia Public domain. - Mode - “Error 400.” http://www.abs.gov.au/websitedbs/D3310114.nsf/Home/%C2%A9+Copyright?OpenDocument. Austrailian Bureau of Statistics CC BY. - “Comparison mean median mode.” http://en.wikipedia.org/wiki/File:Comparison_mean_median_mode.svg. Wikipedia CC BY-SA.	2,917	common-pile/pressbooks_filtered	https://open.ocolearnok.org/reach-higher-data-analysis/chapter/measures-of-relative-standing/	pressbooks	pressbooks-0000.json.gz:95252	https://open.ocolearnok.org/reach-higher-data-analysis/chapter/measures-of-relative-standing/
kTVes4TNrXIVeTi3	Safety, Health and Nutrition in Early Childhood Education	9 Supportive Health Care Learning Objectives By the end of this chapter, you should be able to: - Identify symptoms of infectious disease that is common during early childhood. - Outline criteria for exclusion from care for ill children and staff. - Describe considerations programs must make regarding caring for children that are mildly ill. - Recall licensing requirements for handling medication in early care and education programs. - Explain the communication about illness that should happen between families and early care and education programs. Illness in Early Care and Education Programs The most frequent infectious disease symptoms that are reported by early care and education settings are sore throat, runny nose, shortness of breath or cough, fever, vomiting and diarrhea (gastroenteritis), earaches, and rashes. However, these are not the symptoms that necessarily lead to absences. In fact, although respiratory symptoms are most common, it’s rashes and gastrointestinal disease that more often keep children from attending their early education programs. This is more a reflection of exclusion policies than real risk of serious illness.[2] It’s important for early childhood programs to identify illness accurately and respond in ways that protect all children and staff health (whether it be to allow them to stay in care or to exclude them from care). Identifying Infectious Disease When you are familiar with different infectious diseases, it’s easier to identify them in children and know whether or not children (and staff) who are affected should be excluded from the early care and education program. Common Cold A child is sneezing and has a stuffy, runny nose. It’s quite likely that they have a common cold. As presented in Chapter 8, children get sick many times a year, probably between 4 and 12 times, depending on age and amount of time in child care. Many of these are likely due to the common cold. More than 200 viruses can cause a cold, but rhinoviruses are the most common type. Symptoms of a cold usually peak within 2 to 3 days and can include: - Sneezing - Stuffy nose - Runny nose - Sore throat - Coughing - Mucus dripping down your throat (post-nasal drip) - Watery eyes - Fever (although most people with colds do not have fever). When viruses that cause colds first infect the nose and air-filled pockets in the face (sinuses), the nose makes clear mucus. This helps wash the viruses from the nose and sinuses. After 2 or 3 days, mucus may change to a white, yellow, or green colour. This is normal and does not mean an antibiotic is needed. Some symptoms, particularly runny nose, stuffy nose, and cough, can last for up to 10 to 14 days, but those symptoms should be improving during that time. There is no cure for a cold. It will get better on its own—without antibiotics. When a child with a cold is feeling well enough to participate and staff are able to provide adequate care for them and all of the other children, the child does not need to be excluded from care. Because colds can have similar symptoms to flu, it can be difficult to tell the difference between the two illnesses based on symptoms alone. Flu and the common cold are both respiratory illnesses, but they are caused by different viruses. [2] Influenza (Flu) In general, flu is worse than a cold, and symptoms are more intense. People with colds are more likely to have a runny or stuffy nose. Colds generally do not result in serious health problems, such as pneumonia, bacterial infections, or hospitalizations. Flu can have very serious associated complications. [3] Flu can cause mild to severe illness, and at times can lead to death. Flu usually comes on suddenly. People who have flu often feel some or all of these symptoms: - Fever (common, but not always) or feeling feverish/chills - Cough - Sore throat - Runny or stuffy nose - Muscle or body aches - Headaches - Fatigue (tiredness) - Some people may have vomiting and diarrhea, though this is more common in children than adults. Most people who get flu will recover in a few days to less than two weeks, but some people will develop complications (such as pneumonia) as a result of flu, some of which can be life-threatening and result in death. Sinus and ear infections are examples of moderate complications from flu, while pneumonia is a serious flu complication that can result from either influenza virus infection alone or from co-infection of flu virus and bacteria. Other possible serious complications triggered by flu can include inflammation of the heart (myocarditis), brain (encephalitis) or muscle (myositis, rhabdomyolysis) tissues, and multi-organ failure (for example, respiratory and kidney failure). Flu virus infection of the respiratory tract can trigger an extreme inflammatory response in the body and can lead to sepsis, the body’s life-threatening response to infection. Flu also can make chronic medical problems worse. For example, people with asthma may experience asthma attacks while they have flu. [5] A yearly flu vaccine is the first and most important step in protecting against influenza and its potentially serious complications for everyone 6 months and older. While there are many different flu viruses, flu vaccines protect against the 3 or 4 viruses that research suggests will be most common. Flu vaccination can reduce flu illnesses, doctors’ visits, missed school due to flu, prevent flu-related hospitalizations, and reduce the risk of dying from influenza. Also, there are data to suggest that even if someone gets sick after vaccination, their illness may be milder. [6] Once a person has the flu, their health care provider may recommend antiviral drugs. When used for treatment, antiviral drugs can lessen symptoms and shorten the length of sickness by 1 or 2 days. They also can prevent serious flu complications, like pneumonia. For people at high risk of serious flu complications (including children), treatment with antiviral drugs can mean the difference between milder or more serious illness possibly resulting in a hospital stay. CDC recommends prompt treatment for people who have influenza infection or suspected influenza infection and who are at high risk of serious flu complications. [7] As with a cold, a child with the flu does not need to be excluded if staff can care for them and all of the other children and they feel well enough to participate. Avoiding Spreading Germs to Others Early care and education programs should teach children and model good cough and sneeze etiquette. Always sneeze or cough into a tissue that is discarded after use. If a tissue is not available, use your upper sleeve, completely covering the mouth and nose. Always wash hands after coughing, sneezing, and blowing noses. [11] Sinusitis (Sinus Infection) Sinus infections happen when fluid builds up in the air-filled pockets in the face (sinuses), which allows germs to grow. Viruses cause most sinus infections, but bacteria can cause some sinus infections. Common symptoms of sinus infections include: - Runny nose - Stuffy nose - Facial pain or pressure - Headache - Mucus dripping down the throat (post-nasal drip) - Sore throat - Cough - Bad breath. Most sinus infections usually get better on their own without antibiotics. [9]As with colds and flu, a child does not need to be automatically excluded from care for a sinus infection. Pause to Reflect What was your last experience with an upper respiratory infection (such as cold, flu, or sinus infection? - If a child had the same symptoms as you, would they have needed to be excluded from care? Sore Throat A sore throat can make it painful to swallow. A sore throat can also feel dry and scratchy. Sore throat can be a symptom of the common cold, allergies, strep throat, or other upper respiratory tract illness. Strep throat is an infection in the throat and tonsils caused by bacteria called group A Streptococcus (also called Streptococcus pyogenes). Infections from viruses are the most common cause of sore throats. The following symptoms suggest a virus is the cause of the illness instead of the bacteria called group A strep: - Cough - Runny nose - Hoarseness (changes in your voice that makes it sound breathy, raspy, or strained) - Conjunctivitis (also called pink eye). The most common symptoms of strep throat include: - Sore throat that can start very quickly - Pain when swallowing - Fever - Red and swollen tonsils, sometimes with white patches or streaks of pus - Tiny red spots on the roof of the mouth - Swollen lymph nodes in the front of the neck. A doctor can determine the likely cause of a sore throat. If a sore throat is caused by a virus, antibiotics will not help. Most sore throats will get better on their own within one week and are not cause for exclusion from child care. Since bacteria cause strep throat, antibiotics are needed to treat the infection and prevent rheumatic fever and other complications. A doctor cannot tell if someone has strep throat just by looking in the throat. If a doctor suspects strep throat, they may test to confirm diagnosis. A child with strep throat should be excluded from care until they no longer have fever AND have taken antibiotics for at least 24 hours. [10] Ear Infection There are different types of ear infections. Middle ear infection (acute otitis media) is an infection in the middle ear. Another condition that affects the middle ear is called otitis media with effusion. It occurs when fluid builds up in the middle ear without being infected and without causing fever, ear pain, or pus build-up in the middle ear. When the outer ear canal is infected, the condition is called swimmer’s ear, which is different from a middle ear infection. Middle Ear Infection A middle ear infection may be caused by: - Bacteria, like Streptococcus pneumoniaeand Haemophilus influenza (nontypeable) – the two most common bacterial causes. - Viruses, like those that cause colds or flu. Common symptoms of middle ear infection in children can include: - Ear pain - Fever - Fussiness or irritability - Rubbing or tugging at an ear - Difficulty sleeping. A can make the diagnosis of a middle ear infection by looking inside the child’s ear to examine the eardrum and see if there is pus in the middle ear. Antibiotics are often not needed for middle ear infections because the body’s immune system can fight off the infection on its own. However, sometimes antibiotics, such as amoxicillin, are needed to treat severe cases right away or cases that last longer than 2–3 days. [12] Swimmer’s Ear Ear infections can be caused by leaving contaminated water in the ear after swimming. This infection, known as “swimmer’s ear” or otitis externa, is not the same as the common childhood middle ear infection. The infection occurs in the outer ear canal and can cause pain and discomfort for swimmers of all ages. Symptoms of swimmer’s ear usually appear within a few days of swimming and include: - Itchiness inside the ear. - Redness and swelling of the ear. - Pain when the infected ear is tugged or when pressure is placed on the ear. - Pus draining from the infected ear. Although all age groups are affected by swimmer’s ear, it is more common in children and can be extremely painful. If swimmer’s ear is suspected, a healthcare provider should be consulted. Swimmer’s ear can be treated with antibiotic ear drops. [13] They survive by feeding on human blood. Lice infestations are spread most commonly by close person-to-person contact. Lice move by crawling; they cannot hop or fly. Adult head lice are 2–3 mm in length. Head lice infest the head and neck and attach their eggs to the base of the hair shaft. Lice move by crawling; they cannot hop or fly. [14] Symptoms of a head lice infestation include: - Tickling feeling of something moving in the hair. - Itching, caused by an allergic reaction to the bites of the head louse. - Irritability and difficulty sleeping; head lice are most active in the dark. - Sores on the head caused by scratching. These sores can sometimes become infected with bacteria found on the person’s skin. Head-to-head contact with a person who already has an infestation is the most common way to get head lice. Head-to-head contact is common during play at school, at home, and elsewhere (sports activities, playground, slumber parties, camp). Although uncommon, head lice can be spread by sharing clothing or belongings. This happens when lice crawl, or the nits that are attached to shed hair hatch, and get on the shared clothing or belongings. Examples include: - Sharing clothing (hats, scarves, coats, sports uniforms) or articles (hair ribbons, barrettes, combs, brushes, towels, stuffed animals) recently worn or used by a person with an infestation; - Or lying on a bed, couch, pillow, or carpet that has recently been in contact with a person with an infestation. Dogs, cats, and other pets do not play a role in the spread of head lice. The diagnosis of a head lice infestation is best made by finding a live nymph or adult louse on the scalp or hair of a person. Because nymphs and adult lice are very small, move quickly, and avoid light, they can be difficult to find. Use of a magnifying lens and a fine-toothed comb may be helpful to find live lice. If crawling lice are not seen, finding nits firmly attached within a ¼ inch of base of the hair shafts strongly suggests, but does not confirm, that a person is infested and should be treated. Nits that are attached more than ¼ inch from the base of the hair shaft are almost always dead or already hatched. Nits are often confused with other things found in the hair such as dandruff, hair spray droplets, and dirt particles. If no live nymphs or adult lice are seen, and the only nits found are more than ¼-inch from the scalp, the infestation is probably old and no longer active and does not need to be treated. [16] Treatment for head lice is recommended for persons diagnosed with an active infestation. All household members and other close contacts should be checked; those persons with evidence of an active infestation should be treated with an over-the-counter or prescription medication (following the provided instructions). Hats, scarves, pillow cases, bedding, clothing, and towels worn or used by the person with the infestation in the 2-day period just before treatment is started can be machine washed and dried using the hot water and hot air cycles because lice and eggs are killed by exposure for 5 minutes to temperatures greater than 128.3°F. Items that cannot be laundered may be dry-cleaned or sealed in a plastic bag for two weeks. Items such as hats, grooming aids, and towels that come in contact with the hair of a person with an infestation should not be shared. Vacuuming furniture and floors can remove hairs that might have viable nits attached. Head lice do not survive long if they fall off a person and cannot feed. After treatment, it’s important to check the hair and comb with a nit comb to remove nits and lice every 2–3 days which will decrease the chance of self–reinfestation. Checking for 2–3 weeks will ensure that all lice and nits are gone. [18] No More “No Nits” Policies Children diagnosed with live head lice do not need to be sent home early from early care and education programs or school; they can go home at the end of the day, be treated, and return to class after appropriate treatment has begun. Nits may persist after treatment, but successful treatment should kill crawling lice. Head lice can be a nuisance but they have not been shown to spread disease. Personal hygiene or cleanliness in the home or school has nothing to do with getting head lice. Both the Canadian Pediatric Society and the American Academy of Pediatrics (AAP) advocate that “no-nit” policies should be discontinued. “No-nit” policies that require a child to be free of nits before they can return to schools should be discontinued for the following reasons: - Many nits are more than ¼ inch from the scalp. Such nits are usually not viable and very unlikely to hatch to become crawling lice, or may in fact be empty shells, also known as ‘casings’. - Nits are cemented to hair shafts and are very unlikely to be transferred successfully to other people. - The burden of unnecessary absenteeism to the students, families and communities far outweighs the risks associated with head lice. - Misdiagnosis of nits is very common during nit checks conducted by nonmedical personnel. [19] Pause to Reflect What experience with or knowledge do you have about policies that specific early education and care program and schools have on head lice? - Are (or were) those policies “no nits” or in line with the recommendations above? Danger of Infectious Disease for Adults Because early care and education program employees are around children who are at higher risk of infectious diseases and have limited understanding of hygiene practices, those employees are also at greater risk for getting sick. While most illness that are spread in early care and education programs are not serious, some can be very dangerous. Knowledge about illness and how to prevent its spread helps. Being fully immunized (from childhood illness and or vaccines) protects adult health as well. Employees that are or could become pregnant want to be especially careful because first time exposure to chickenpox, cytomegalovirus (CMV), Fifths disease, and Rubella can cause major damage to fetal health, birth defects, and even fetal death. [20] Reportable Diseases Some diseases are enough of a threat to the community that it is required that diagnosed cases are reported to the local health department. The Nova Scotia Health Protection Act requires that the diseases and conditions listed below be reported to Public Health Services in the Nova Scotia Health Authority(NSHA). SARS-CoV-2 (COVID-19) was added to the list of reportable diseases under the regulations November 9th, 2021. For more information on case definitions for notifiable diseases in Nova Scotia, please refer to the Nova Scotia Surveillance Guidelines for Notifiable Diseases and Conditions: A-Z List. Exclusion Policies Most children with mild illnesses can safely attend child care. “Many health policies concerning the care of ill children [including exclusion policies] have been based upon common misunderstandings about contagion, risks to ill children, and risks to other children and staff. Current research clearly shows that certain ill children do not pose a health threat. Also, the research shows that keeping certain other mildly ill children at home or isolated at the child care setting will not prevent other children from becoming ill.” [21] What to do When a Child Requires Exclusion When a child becomes ill enough to be excluded, they should be immediately isolated from other children. Early care and education programs are required to be equipped to isolate and care for any child who becomes ill during the day. The isolation area shall be located to afford easy supervision of children by center staff and equipped with a mat, cot, couch or bed for each ill child (or a crib if caring for infants). The child’s authorized representative shall be notified immediately when the child becomes ill enough to require isolation, and shall be asked to have the child picked up from the center as soon as possible. [22] In Nova Scotia[23] a child should be excluded and sent home from a program if any of the following conditions are noted: - An illness that prevents the child from participating comfortably in the program activities, including playing outdoors - An illness that results in a need for care that is greater than the staff can provide without compromising the health and safety of other children. - Fever in a child younger than 6 months. - Fever AND other symptoms (sore throat, vomiting, diarrhea, earache) or behaviour change in children older than 6 months. - Sudden change in patterns of behaviour: - Listlessness or excessive sleepiness - Excessive fussiness or crankiness - Difficulty breathing - Persistent cough - Diarrhea: 2 or more episodes or diarrhea with fever, vomiting or blood in the stool. - Vomiting: 2 or more episodes. - Severe abdominal pain or abdominal pain with any other symptoms of illness. - Rash AND fever or other sign of illness. - Has a wound that cannot be covered. - Yellowish skin or eyes, or “jaundice”. The Nova Scotia Guidelines for Communicable Disease Prevention and Control for Childcare Programs and Family Home Day Care Agencies contains information and requirements for managing communicable diseases in child care centres in Nova Scotia. Pause to Reflect Consider the following situations. - Should each child be excluded from care or not? - If so, why and when should the child return? - If not, what should the teacher/caregiver do? - Mario’s dad drops him off and let’s Ms. Michelle know that he is a little under the weather. He is not running a fever, but has a mild cough and a runny nose. But he ate a good breakfast and has a pretty typical level of energy. - About an hour into the day, Li vomits. Mr. Abraham checks and she has a fever of 101.3°. She looks a little pale and just wants to lay down. As he goes to call Li’s family, she vomits again. - When Latanya goes to change Daniel’s diaper she notices a rash on his stomach. She checks his temperature and he is not running a fever. He is not scratching at it or seemingly in any discomfort. She remembers that he has a history of eczema and contact dermatitis. - Apurva wakes up from naptime with discharge coming from a slightly swollen and bloodshot right eye. She tells Ms. Maria that her eye hurts and is “kind of itchy.” - Now, come up with your own examples of a child that should be excluded from care and that should not automatically be excluded. Caring for Mildly Ill Children Because young in early care and education programs have high incidence of illness and may have conditions (such as eczema and asthmas), providers should be prepared to care for mildly ill children, at least temporarily. And since we know that excluding most mildly ill children doesn’t prevent the spread of illness and can have negative effects on families, programs should consider whether they can care for children with mild symptoms (not meeting the exclusion policy). The California Childcare Health Program poses the following questions to consider: - Are there sufficient staff (including volunteers) to provide minor modifications that a child might need (such as quiet activities or extra fluids)? - Are staff willing and able to care for the child’s symptoms (such as wiping a runny nose and checking a fever) without neglecting the care of other children in the group? - Is there a space where the mildly ill child can rest if needed? - Are families able or willing to pay extra for sick care if other resources are not available, so that you can hire extra staff as needed? - Have families made alternative arrangements for someone to pick up and care for their ill children if they cannot? It’s important that programs recognize the families have to weigh many things when trying to decide whether or not to send a child to child care. They must consider how the child feels (physically and emotionally), whether or not the program can provide care for the specific needs of the child, what alternative care arrangements are available, as well as the income they may lose if they have to stay home. [24] Responding to Illness that Requires Medical Care Some conditions, require immediate medical help. If the parents can be reached, tell them to come right away and to notify their medical provider. Call Emergency Medical services (9-1-1) immediately and also notify parents if any of the following things happen: - You believe a child needs immediate medical assessment and treatment that cannot wait for parents to take the child for care. - A child has a stiff neck (that limits his ability to put his chin to his chest) or severe headache and fever. - A child has a seizure for the first time. - A child who has a fever as well as difficulty breathing. - A child looks or acts very ill, or seems to be getting worse quickly. - A child has skin or lips that look blue, purple or gray. - A child is having difficulty breathing or breathes so fast or hard that he or she cannot play, talk, cry or drink. - A child complains of a headache or feeling nauseous, or is less alert or more confused, after a hard blow to the head. - Multiple children have injuries or serious illness at the same time. - A child has a large volume of blood in the stools. - A child has a suddenly spreading blood-red or purple rash. - A child acts unusually confused. - A child is unresponsive or [has] decreasing responsiveness. Tell the parent to come right away, and get medical help immediately, when any of the following things happen. If the parent or the child’s medical provider is not immediately available, call 9-1-1 (EMS) for immediate help: - A fever in any child who appears more than mildly ill. - An infant under 2 months of age has an axillary (“armpit”) temperature above 100.4º F. - An infant under four months of age has two or more forceful vomiting episodes (not the simple return of swallowed milk or spit-up) after eating. - A child has neck pain when the head is moved or touched. - A child has a severe stomach ache that causes the child to double up and scream. - A child has a stomach ache without vomiting or diarrhea after a recent injury, blow to the abdomen or hard fall. - A child has stools that are black or have blood mixed through them. - A child has not urinated in more than eight hours, and the mouth and tongue look dry. - A child has continuous, clear drainage from the nose after a hard blow to the head. - A child has a medical condition outlined in his special care plan as requiring medical attention. - A child has an injury that may require medical treatment such as a cut that does not hold together after it is cleaned. [25] Administering Medications Some children in your early care and education setting may need to take medications during the hours you provide care for them. It’s important that early care and education programs have a written policy for the use of prescription and nonprescription medication. [26] According to licensing, programs that choose to handle medications must abide by the following: - All prescription and nonprescription medications shall be centrally stored in a safe place inaccessible to children, with an unaltered label, and labeled with the child’s name and date - A refrigerator shall be used to store any medication that requires refrigeration. - Prescription medications may be administered with written permission by the child’s authorized representatives in accordance with the label instructions by the physician. - Nonprescription medications may be administered without approval or instructions from the child’s physician with written approval and instructions from the child’s authorized representative and when administered in accordance with the product label directions. Valid reasons for an early care and education program to consider administering medication. - Some medication dosing cannot be adjusted to be taken before and after care (and keeping them out of care when otherwise well enough to attend, would be a hardship for families. - Some children may have chronic conditions that may require urgent administration of medication (such as asthma and diabetes). [28] Communication with Families When children are excluded from care, it’s important to provide documentation for families of how the child meets the guidelines in your exclusion policy and what needs to happen before the child can return to care. See Appendix K for a possible form that programs could use. Programs are also required to inform families when children are exposed to a communicable disease. See Appendix L for an example of a notice of exposure form you can provide to families so they know what signs of illness to watch for and to seek medical advice when necessary. [29] Pause to Reflect Why is it important for early care and education programs to communicate clearly with families regarding communicable illness? Summary Becoming familiar with infectious diseases that are common in early childhood enables early care and education program staff to identify illness and respond appropriately. This included knowing when children (and staff) should be excluded from care and what needs to happen before they should come back. Programs must create policies on how they will handle children that are mildly ill (those that need care before they can be picked up from care and those that do not require exclusion) and children who have illness that requires medical care. Programs who choose to administer medication, must be familiar with the licensing regulations they must follow. Open communication with families is important when a child becomes ill or is potentially exposed to an illness. Helping families understand and follow policies regarding exclusion is vital to keeping everyone in the program as healthy as possible. Chapter 9 Review Resources for Further Exploration - Health and Safety in the Child Care Setting: Prevention of Infectious Disease A Curriculum for the Training of Child Care Providers - A Quick Guide to Common Childhood Diseases (Canadian resource) - Common Childhood Infections – A Guide for Principals, Teachers and Child Care Providers (Canadian resource): - Georgia School Resource Health Manual - Diseases & Conditions A-Z Index - Childhood Infectious Illnesses - Appropriate Antibiotic Use - When to Keep Your Child Home from Child Care References [1] Image by College of the Canyons ZTC Team is based on image from Managing Infectious Disease in Head Start Webinar by Head Start Early Childhood Learning & Knowledge Center, which is in the public domain??? [2] Infectious Diseases: Prevention and Management by Head Start Early Childhood Learning & Knowledge Center is in the public domain [3] Image by College of the Canyons ZTC Team is based on image from Managing Infectious Disease in Head Start Webinar by Head Start Early Childhood Learning & Knowledge Center, which is in the public domain??? [11] Image by the Centers for Disease Control and Prevention is in the public domain [12] Common Colds: Protect Yourself and Others by the Centers for Disease Control and Prevention is in the public domain - Image by the Centers for Disease Control and Prevention. (2023). Common Cold. [public domain]. https://www.cdc.gov/antibiotic-use/colds.html?CDC_AA_refVal=https%3A%2F%2Fwww.cdc.gov%2Fantibiotic-use%2Fcommunity%2Ffor-patients%2Fcommon-illnesses%2Fcolds.html ↵ - Centers for Disease Control and Prevention. (2023). Common Cold. [public domain]. https://www.cdc.gov/antibiotic-use/colds.html?CDC_AA_refVal=https%3A%2F%2Fwww.cdc.gov%2Fantibiotic-use%2Fcommunity%2Ffor-patients%2Fcommon-illnesses%2Fcolds.htm ↵ - Centers for Disease Control and Prevention. (2023). Common Cold. [public domain]. https://www.cdc.gov/antibiotic-use/colds.html?CDC_AA_refVal=https%3A%2F%2Fwww.cdc.gov%2Fantibiotic-use%2Fcommunity%2Ffor-patients%2Fcommon-illnesses%2Fcolds.htm ↵ - Symptoms of Influenza Image by Mikael Häggström is in the public domain. ↵ - Centers for Disease Control and Prevention. (2022). Flu Symptoms & Complications. [public domain]. https://www.cdc.gov/flu/symptoms/symptoms.htm ↵ - Centers for Disease Control and Prevention. (2024). Influenza (Flu) Preventive Steps. [public domain]. https://www.cdc.gov/flu/prevent/prevention.htm ↵ - Centers for Disease Control and Prevention. (2024). Flu Treatment. [public domain]. https://www.cdc.gov/flu/treatment/index.html ↵ - Image by the Centers for Disease Control and Prevention. (2019). Sinus Infection. [public domain]. https://www.cdc.gov/antibiotic-use/sinus-infection.html?CDC_AA_refVal=https%3A%2F%2Fwww.cdc.gov%2Fantibiotic-use%2Fcommunity%2Ffor-patients%2Fcommon-illnesses%2Fsinus-infection.html ↵ - Centers for Disease Control and Prevention. (2019). Sinus Infection. [public domain]. https://www.cdc.gov/antibiotic-use/sinus-infection.html?CDC_AA_refVal=https%3A%2F%2Fwww.cdc.gov%2Fantibiotic-use%2Fcommunity%2Ffor-patients%2Fcommon-illnesses%2Fsinus-infection.html ↵ - Centers for Disease Control and Prevention. (2021). Sore Throat. [public domain]. https://www.cdc.gov/antibiotic-use/sore-throat.html?CDC_AA_refVal=https%3A%2F%2Fwww.cdc.gov%2Fantibiotic-use%2Fcommunity%2Ffor-patients%2Fcommon-illnesses%2Fsore-throat.html ↵ - Centers for Disease Control and Prevention. (2021). Ear Infection. [public domain]. https://www.cdc.gov/antibiotic-use/ear-infection.html?CDC_AA_refVal=https%3A%2F%2Fwww.cdc.gov%2Fantibiotic-use%2Fcommunity%2Ffor-patients%2Fcommon-illnesses%2Fear-infection.html ↵ - Centers for Disease Control and Prevention. (2021). Ear Infection. [public domain]. https://www.cdc.gov/antibiotic-use/ear-infection.html?CDC_AA_refVal=https%3A%2F%2Fwww.cdc.gov%2Fantibiotic-use%2Fcommunity%2Ffor-patients%2Fcommon-illnesses%2Fear-infection.html ↵ - Centers for Disease Control and Prevention. (2022). Healthy Swimming: Ear Infections. [public domain]. https://www.cdc.gov/healthywater/swimming/swimmers/rwi/ear-infections.html ↵ - Centers for Disease Control and Prevention. (2019). Parasites - Lice. [public domain]. https://www.cdc.gov/parasites/lice/ ↵ - Image retrieved from Centers for Disease Control and Prevention. (2019). Parasites - Lice. [public domain]. https://www.cdc.gov/parasites/lice/ ↵ - Centers for Disease Control and Prevention. (2020). Head Lice: FAQ. [public domain]. https://www.cdc.gov/parasites/lice/head/gen_info/faqs.html ↵ - Image retrieved from Centers for Disease Control and Prevention. (2020). Head Lice: FAQ. [public domain]. https://www.cdc.gov/parasites/lice/head/gen_info/faqs.html ↵ - Centers for Disease Control and Prevention. (2019). Head Lice: Treatment. [public domain]. https://www.cdc.gov/parasites/lice/head/treatment.html ↵ - Centers for Disease Control and Prevention. (2015). Head Lice Information for Schools. [public domain]. https://www.cdc.gov/parasites/lice/head/schools.html ↵ - California Child Care Health Program. (2011). Health and Safety in the Child Care Setting: Prevention of Infectious Disease. University of California San Francisco. Retrieved from https://cchp.ucsf.edu/sites/g/files/tkssra181/f/idc2book.pdf ↵ - California Childcare Health Program. (2018). Preventive Health and Safety in the Child Care Setting: A Curriculum for the Training of Child Care Providers (3rd ed.). University of California, San Francisco. Retrieved from https://cchp.ucsf.edu/sites/g/files/tkssra181/f/PHT-Handbook-Student-2018-FINAL.pdf ↵ - California Department of Social Services. (1998). Child Care Center General Licensing Requirements: Immunizations. [public domain]. https://www.cdss.ca.gov/Portals/9/Regs/5cccman.pdf?ver=2017-02-28-163427-113 ↵ - This section is reproduced from: Nova Scotia Health Promotion and Protection. (2015). Guidelines for Communicable Disease Prevention and Control for Childcare Programs and Family Home Day Care Agencies. https://www.novascotia.ca/dhw/cdpc/documents/guidelines_cdpc_child_care_setting.pdf ↵ - California Childcare Health Program. (2018). Preventive Health and Safety in the Child Care Setting: A Curriculum for the Training of Child Care Providers (3rd ed.). University of California, San Francisco. Retrieved from https://cchp.ucsf.edu/sites/g/files/tkssra181/f/PHT-Handbook-Student-2018-FINAL.pdf ↵ - California Childcare Health Program. (2018). Preventive Health and Safety in the Child Care Setting: A Curriculum for the Training of Child Care Providers (3rd ed.). University of California, San Francisco. Retrieved from https://cchp.ucsf.edu/sites/g/files/tkssra181/f/PHT-Handbook-Student-2018-FINAL.pdf ↵ - California Childcare Health Program. (2018). Preventive Health and Safety in the Child Care Setting: A Curriculum for the Training of Child Care Providers (3rd ed.). University of California, San Francisco. Retrieved from https://cchp.ucsf.edu/sites/g/files/tkssra181/f/PHT-Handbook-Student-2018-FINAL.pdf ↵ - Image of Close-up of a woman pours a spoon of medicinal mixture by Marco Verch is licensed under CC BY 2.0 ↵ - California Childcare Health Program. (2018). Preventive Health and Safety in the Child Care Setting: A Curriculum for the Training of Child Care Providers (3rd ed.). University of California, San Francisco. Retrieved from https://cchp.ucsf.edu/sites/g/files/tkssra181/f/PHT-Handbook-Student-2018-FINAL.pdf ↵ - California Childcare Health Program. (2018). Preventive Health and Safety in the Child Care Setting: A Curriculum for the Training of Child Care Providers (3rd ed.). University of California, San Francisco. Retrieved from https://cchp.ucsf.edu/sites/g/files/tkssra181/f/PHT-Handbook-Student-2018-FINAL.pdf ↵	7,469	common-pile/pressbooks_filtered	https://pressbooks.nscc.ca/ecenutrition/chapter/chapter-nine-supportive-health-care/	pressbooks	pressbooks-0000.json.gz:69770	https://pressbooks.nscc.ca/ecenutrition/chapter/chapter-nine-supportive-health-care/
tdWizq5oI0vjDqF9	The OER Starter Kit for Program Managers	Supporting OER Adoption 13 Abbey K. Elder OER program managers are often asked to locate OER as part of their daily work. This work is usually supported through OER consultations, meetings with faculty that inform the content and subjects that the OER support staff will seek out. The OER consultation process is similar to research consultations, which the librarians on your team may already be familiar with. Locating and sharing content may be a simple exchange over email, or it may be a more involved process that requires the support of go-betweens like subject liaison librarians or other OER support staff. To help you consider how you might implement this work at your institution, a basic guide for structuring an OER consultation is provided below. There are four basic steps to every OER consultation: - The preliminary message or meeting, where you gather course-level information. - Follow-up meetings, which dig deeper into the needs of the instructor. - The identification of content that fits the parameters identified in steps 1 and 2. - Sharing content you identified with the instructor. Gather Information Before you can start looking for open content, you first have to gather information about the course in which it will be used. An easy way to do this is through a standard OER consultation request form. Create a form that faculty must fill out to request a consultation with you or another support person at your institution for help locating OER. When sharing a form like this, be sure to place it prominently in a place that is easy for faculty to find. A form that people can’t find isn’t of much use to you! A basic OER consultation request form should contain at least three things: - Instructor’s contact information - Course code and number - Details about the current textbook(s) and/or readings currently assigned In addition to these three items, you can also ask for a copy of the instructor’s syllabus and/or course schedule, though this will require a “file upload” option within the form itself, which is not possible on every platform. You will need this information later, but you can request it from the instructor directly if necessary. Although consultation request forms can be as simple or as complex as you’d like, we recommend keeping the forms as short as possible to lessen the burden on faculty filling out the form. A good example of a basic OER Consultation Request Form is provided below, from Florida State University Libraries: Once a form has been filled out, you or another member of your team will need to follow up with the instructor for the next step of their consultation. For example, you may ask that a student worker on your team conduct the initial OER search for the instructor, or that the subject liaison librarian for your instructor’s department meet with them for the initial consultation. Some project management tools (e.g., Smartsheet) can alert members of your team when a consultation request form has been filled out so they can be prepared to follow up with faculty as well. If you prefer to handle the preliminary consultations and information gathering yourself, you can connect your form to your calendar app of choice. Set Expectations In addition to setting up a consultation request form, it is useful to set expectations for your OER support early by letting instructors know when you will get back to them for follow-up, how soon you can meet, and what kind of support they can expect from you and/or your team. Setting expectations may be done over email, during the first consultation meeting, or laid out on the same website where your consultation request form is housed. This example from the University of Missouri Libraries’ OER Guide is particularly in-depth and covers expectations for communication and the support staff who may work with the instructor during and after the consultation: “Complete the A&OER Team Consultation Request Form. Your answers to this simple, one-page questionnaire will help your support team understand your specific needs. We will form a small support team (3 to 5 people) of librarians, instructional designers, and bookstore administrators who are familiar with your course, department, and materials in your discipline. Team members will review your request and begin identifying open textbooks, affordable (<$40) textbooks, government documents, library materials, and items in the public domain that might meet your needs. Your team may ask for a copy of your syllabus, titles and ISBNs of texts that have been required or recommended for your course in past semesters, and / or any A&OER titles or repositories that you are familiar with or have already reviewed. A representative from your support team will work with you to identify a good time to meet in person or virtually. In this meeting, your team will present you with open, freely available, and / or affordable educational resources that could be a good fit for your course. By the end, you and your support team will have identified your next steps for evaluating materials, integrating them into your course, and reporting them to the campus bookstore. A team member will be selected to stay in touch with you after the meeting to answer follow-up questions and to ensure that your needs are met.” (University of Missouri Libraries 2020) A boilerplate explanation about the OER consultation process is particularly useful to have on hand when your consultation workflow requires the support of multiple staff. It not only reviews what kind of support instructors can expect to get from your team, but also provides examples of the types of staff members who will be supporting them. Not every OER program manager will have a team to back up their work. Be clear about what you can do to support your instructors’ needs, and what is outside of your job’s scope. This will help you manage your workload and balance instructors’ expectations accordingly. Ask Deeper Questions Once you have enough information to understand your instructor’s basic needs, you can set up an initial consultation meeting with them. If the course being reviewed has good examples of OER available, you may want to send these to your instructor ahead of your meeting. This will prepare you both for the conversation ahead and, if the instructor replies to the content prior to your meeting, will help you better understand the types of materials your instructor is interested in. The consultation meeting should focus on the needs of the instructor. Begin building trust with the instructor you are meeting by exploring what they want from the consultation and reviewing what you and/or your team can provide for them. Faculty members may come to the consultation without a clear idea of what they would like to do. As an OER program manager, it is your job to help them chart a path for their course’s redesign process. During this stage, set expectations for the outcomes of your consultation, and come to an agreement on what the final goal(s) for your work will be. How familiar are you with OER? Discuss the instructor’s history with OER and what made them want to consider OER for their course now. This may be a great opportunity for you to learn more about your program’s reputation on campus and how you might improve your work’s visibility. If the instructor is wholly new to OER, explain the variety of formats that OER can be found in, and the affordances that come with an open license (See Chapter 1, Introduction to Open Educational Resources). What is your goal for your course? Discuss what kind of change the instructor is looking for. Do they want to rebuild the curriculum for their course from the ground up, or are they looking for materials that follow the same structure as their current course content? What kinds of materials do you prefer to use in your courses? Identify what kind of materials the faculty member is interested in learning more about. Do they want to find open textbooks, or are they more interested in activities, videos, and modular OER content they can compile to meet their course’s needs? Having a few print OER examples in your office can be helpful at this stage, as it may pave the way for conversations about the various format options for OER (See Figure 12.2). What tool(s) do you typically use in your course? Ask whether the instructor utilizes your institution’s course management system (Canvas, Blackboard, etc.), or a separate course website to communicate and share content with students. This may affect the tools and practices you recommend. What supporting materials do you utilize for this course? If the instructor relies on self-grading homework platforms or ancillary presentations and lecture notes from publishers, you will want to discuss the various free and low-cost options available to replace that content (See Chapter 15, Finding Ancillaries for OER). Alternatively, does the instructor already supplement their course materials with course notes or materials they have personally created? Often, when traditional materials are lacking or require supplement, instructors will create notes, reading lists, or other content to “back up” any traditional, commercial content used in their course. This instructor-created content can be reused with OER as well, or even adapted into a new open resource in the future. Would you be able to adapt content if we find something close to your needs? This question may be concerning for some instructors, so be thoughtful in the way you choose to broach this topic. Explain that OER can be adapted in various ways, and that the time commitment for this work may vary based on the materials you identify. An effective adaptation may be as simple as rearranging chapters or as complex as creating a new open textbook from multiple resources. Tools like the LibreTexts Remixer can make adaptation work easier, but that doesn’t mean that adapting OER is “easy.” Make sure that any work your instructor would need to do to get their OER ready for their course is known to them, and that any support you or your team can offer is clear and addressed up front. The last thing you want in this new relationship is to promise more than you can deliver, or to offload unexpected work onto your instructor. Would you be interested in an open pedagogy approach? For instructors who are engaged and interested in learning more, discuss the flexibility and potential of open pedagogy for adding value to their course and supporting student learning outcomes (See Chapter 2, Open Education). In addition to adding a more interactive component to the course, open pedagogy projects can help build on the OER used within the course. For example, students might develop test banks to supplement their open textbook, or comment on and even edit open readings implemented in a course. Review some examples with the instructor and tools available that can support these processes, like Hypothesis for social annotation. As with previous topics, though, you will want to acknowledge in your discussion that open pedagogy is not something they can implement quickly or easily. It is often a process that changes over time, to account for the interests and needs of students and address feedback from past courses. What is your timeline for this project? Ask how often the instructor teaches the course(s) in which they want to use OER, and when they will be teaching the course(s) next. How soon would they like to have a set of resources to review, and what does their current workload look like, for reviewing and potentially adapting content? Make it clear that the open content you share will take time to review and integrate into the instructor’s course. Additionally, depending on your institution’s course adoption reporting process, the instructor may need to determine their next term’s course materials only two or three months into the current term. This may affect your timeline if the instructor you are working with wants to use OER in their course quickly. Help the instructor plot out a timeline that is feasible for both of you to handle, even if this means they might not adopt OER until the following year. Would funding help you complete this work? Finally, if your institution has an OER grant program, gauge the instructor’s interest in applying for a grant to support the adoption, adaptation, or creation of new content. Tread carefully here, though. OER consultations should always lead with the instructor’s interests and needs. Do not push for projects that would require additional work from the instructor until and unless the instructor has shown interest in this type of work. A grant can be incredibly helpful for faculty who are on a 9- or 10-month appointment and lack summer funding for their work, but if your grant only covers OER adaptation or creation, this may be beyond your instructor’s interest. Discuss the possibility with your instructor that you may have difficulty locating enough content or content in the specific areas covered by their course. Figure out what the minimum requirement would be for your search to be considered a “success.” Conversations about failure are never easy, but they are important to have, whether they take place during your first meeting with an instructor or later on. Searching for Content The person searching for OER may be you, a subject librarian in the faculty member’s field who has been trained on major OER repositories, an instructional designer, or another member of your team. Because of the proliferation of repositories and search tools available, it’s important that those helping you are trained on how to search for OER and the peculiarities of this process. Chapter 13, Searching for Open Content, will go into this process in more depth. If you’ve talked about searching for content with the faculty member, they may want to go out and search for content on their own as well! Consider sharing a worksheet or guidance document to help faculty through this work, such as the OER Treasure Hunt Worksheet (Elder 2020). Sharing Content with Faculty Once you have located some potential resources, it’s time to share them with the instructor. This part of the process can feel like one of the simplest, but there is plenty of room for things to go wrong. For example, you could overload the instructor with potential resources that they will not have time to review or you could present the materials in a way that makes it feel like they are only a collection of links. It’s important at this stage to keep up the same level of professionalism, care, and candor that you’ve presented throughout your OER consultation process. How do you ensure that the resources you are sharing are presented in an organized fashion and easy for your instructor to navigate? An easy way to get around this is by sending content in a template, such as the OER Content Sharing Template (Smith and Elder 2021). Having a template for sharing content can be useful for presenting OER in an attractive way that highlights the pros and cons of each resource alongside basic information about it, such as description, content level, and license. The depth of information you include will depend on your instructor’s needs and the amount of content you’ve found. For example, if you’ve located a plethora of smaller resources, you may want to include “sections” in your template for specific types of material to further organize the results (e.g., readings, modules, exercises, images). Another option for ensuring that the OER list you send is easy to understand is by being selective in what you send. Rather than including everything you found that might fit your instructor’s needs, limit your list to the items that seem like the best fit, based on your knowledge of the course and the resources you found. In your consultation meeting, you will have learned about the topics covered in the instructor’s course and what they want from their course materials. A cursory review of content and tone should help you determine what materials are most likely to meet your instructor’s needs. Sharing a Lack of Content Keep in mind that unlike commercial course materials, which have existed for decades, OER are still a fairly new concept and they have not fully saturated the market yet. There may be gaps in the OER available for some fields, and you may not be able to find anything open for your instructor. Be positive and frank with your instructor if this is the case. Here it’s incredibly useful if you’ve built a rapport with your instructor, since it will help you discuss any roadblocks you encountered in your search and how the instructor would like to proceed. If there is a lack of OER for your instructor’s course, review possible alternatives available through your library’s collections (e-books, article indexes and databases, streaming videos, etc.) and course reserves system, or even commercial content that is more affordable than the previous resources they used. Setting up a regular check-in might be useful as well, so you can check in with the instructor as new OER are published that might be a good fit for their course. In the next chapter, we’ll dive into the process of locating OER in more depth. Conclusion The OER consultation provides a chance for OER program managers and instructors to meet and discuss their mutual interests. The specific process for managing these consultations differs from institution to institution. However, these meetings typically involve a review of the course being supported, a discussion about the course’s content and needs, and the identification and sharing of potentially relevant OER with the instructor. While it might seem like a wholly transactional process, if you manage these discussions well, OER consultations can be an excellent tool for getting to know the instructors on your campus and better supporting their needs. Recommended Resources - Course Mapping and Librarians (West 2015) - Search for OER: Helping Faculty Find OER (McKernan 2015) - Faculty, Are You Ready to Free the Textbook? Flowchart (College Libraries Ontario, n.d.) - Setting up a formal process for consultation scheduling and management can help lessen your workload and streamline the process for instructors who want to get in touch with you and/or your team. - When providing consultations for faculty, manage expectations for the outcomes of the consultation, and outline the process and timeline for locating content. This demystifies the process and helps programs avoid issues where an instructor’s expectations cannot be met. - During your consultation, it is important to learn more about the instructors’ specific needs. Relationship building is an important part of this process, and will help both you and the instructor feel more confident in your ongoing discussions about OER identification, evaluation, and integration. - Using a template to share open content mapped against course needs is one way that OER programs can provide a more professional-looking outcome for OER consultations. These mappings can be saved and reused for other courses in the same discipline as well. References College Libraries Ontario. n.d. “Faculty, Are You Ready to Free the Textbook?” Accessed January 29, 2022. https://tlp-lpa.ca/ld.php?content_id=34087644 Elder, Abbey K. 2020. “OER Treasure Hunt Worksheet.” Accessed January 29, 2022. https://docs.google.com/document/d/1Vc7xg_1LqJQ93gA789-LHLIwDe1ppK0m8IuhcPw_K_0/edit Florida State University Libraries. n.d. “OER Consultation Request.” Accessed January 29, 2022. https://www.lib.fsu.edu/form/oer-consultation-request McKernan, Rowan. 2015. “Search for OER: Helping Faculty Find OER.” In Librarians as Open Education Advocates. Library as Open Education Leader. https://openedadvocates.pressbooks.com/chapter/search-for-oer/ Smith, Shannon M., and Abbey K. Elder. 2021. “OER Content Sharing Template.” Accessed January 22, 2022. https://lib.dr.iastate.edu/materials/12 University of Missouri Libraries. 2020. “Request a Team Consultation.” Open Educational Resources (OER) Library Guide. https://libraryguides.missouri.edu/OER/consultation West, Quill. 2015. “Course Mapping and Librarians.” In Librarians as Open Education Advocates. Library as Open Education Leader. https://openedadvocates.pressbooks.com/chapter/course-mapping-and-librarians/	4,279	common-pile/pressbooks_filtered	https://opentextbooks.uregina.ca/oerstarterkitpm/chapter/chapter-12-managing-oer-consultations/	pressbooks	pressbooks-0000.json.gz:57001	https://opentextbooks.uregina.ca/oerstarterkitpm/chapter/chapter-12-managing-oer-consultations/
E-7N06W5m76hInw1	The American Practical Brewer and Tanner	Produced by Robert Cicconetti and the Online Distributed Proofreading Team at https://www.pgdp.net THE AMERICAN PRACTICAL BREWER AND TANNER: IN WHICH IS EXHIBITED THE WHOLE PROCESS OF Brewing without boiling. Brewing strong Beer with the extract only of the Hop, leaving out the substance. A simple method of giving new Beer all the qualities of age, thereby fitting it for the bottle before it is three weeks old. A simple method of preventing Beer bursting the bottle. An economical mode of constructing Vats above ground, possessing the temperature of the best cellars and thus rendered fireproof. An economical mode by which every Housekeeper may brew his own Beer. A method of brewing good Beer from Bran and Shorts, and of preserving it. The Bordeaux method of making and preparing Claret Wine for shipping, which may be successfully applied to the wines of this country, particularly those of Kaskaskias. The best method and season for malting Indian Corn, from which alone good Beer can be made, a process highly important to Brewers. The best mode of raising Hops. The best mode of preparing Seed Barley for sowing. Best construction and aspect of Breweries and Malt Houses in this country. The French mode of tanning the heaviest Soal Leather in twenty-one days, and Calf Skins in three or four. (Highly important.) BY JOSEPH COPPINGER. Practical Brewer. _NEW-YORK_: PRINTED BY VAN WINKLE AND WILEY, No. 3 Wall Street. 1815. Transcriber's Note: Part of the last sentence in Footnote 6 is illegible and has been marked [remainder of text is illegible]. In addition, the Contents were moved from the rear to the front of this text for the convenience of the reader. CONTENTS. Page. Advertisement 3 Preface 5 The best position for placing a brewery and malt house, also the best aspect, with different arrangements of the vessels 11 A description of the form and plan of a brewery, distribution of the vessels; the most judicious and convenient manner of placing them, with a view to economy, cleanliness, and effect 13 Malt house, the best construction of, with proper barley lofts, dropping room, and flooring, how, and in what manner made, and best likely to last 18 Wooden kilns, how constructed 23 A new and economical construction of vats for keeping beer, which, in this way, may be rendered fire proof, whilst at the same time possessing the temperature of the best cellars, although above ground 29 Grinding, how substituted for 31 Malting 33 Plain practical process of malting 44 Malting winter barley 50 Malting oats ib. Malting rye ib. Malting wheat ib. Indian corn, how malted 51 Fermentation 54 Hops, how cultivated 99 Barley cultivation 109 Table beer 112 Small beer for shipping 113 Keeping table beer 114 Small beer of the best kind 116 Another method to brew small beer 118 Another process for brewing small beer 120 Single ale and table beer 123 Strong beer 126 Table beer, English method of brewing it 129 Unboiled beer 131 Strong beer, brewed with the extract of hops, leaving out the substance 134 Table beer for housekeepers, well worth their attention 136 Fermenting and cleansing in the same vessel 138 Plate of the worker 139 A new method of fermenting strong beer, that will produce a pure and good liquor 140 Process of brewing Windsor ale, on a small scale 142 Reading beer, how brewed 145 Two-penny amber beer, as brewed in London 147 London ale, how brewed 149 Windsor ale, on a large scale 151 Welsh ale, how brewed 154 Wirtemberg ale 156 Hock 158 Scurvy grass ale 160 Dorchester ale 162 Porter 165 Porter process No. I. 167 Porter process No. II. 170 Porter process No. III. 172 Porter malt 174 Porter colouring 176 Strong beer 182 Filtering operation (with a Plate) 189 Returned beer, how to make the most of 193 To Bring several sorts of beer, when mixed, to one uniform taste 194 Finings, the best method of preparing them 195 Heading 197 Bottling beer 198 Brewing coppers, the best method of setting them 202 Pumps, the best construction of, and how freed from ice in winter 205 Cleansing casks 208 To make mead wine 210 To make ginger wine 212 To make currant wine 213 Yest, how prepared to keep good in any climate 214 To make a substitute for brewer's yest 217 Another method 218 Another method 220 Process of making and preparing claret wine for shipping, as practiced in Bordeaux and its neighbourhood 221 Brewing company 227 The author's notice about plans and sections of elevation for breweries and malt houses 230 French mode of tanning 232 _Errata._ In the Advertisement, 4th page, 6th line, first word, for _wine_ read _vine_; and in the next line, first word, for _it_ read _its produce_. In page 25, 25th line, the last word should be omitted, and read thus, _malt or grain intended to be dried on it, requiring less fuel_, &c. In page 36, 25th line, first word, for _proportion_ read _preparation_. SOUTHERN DISTRICT OF NEW-YORK, _ss._ BE IT REMEMBERED, that on the fourteenth day of September, in the fortieth year of the independence of the United States of America, Joseph Coppinger of the said district, has deposited in this office the title of a book, the right whereof he claims as proprietor, in the words and figures following, to wit: "The American Practical Brewer and Tanner: in which is exhibited the whole process of Brewing without boiling; Brewing Strong Beer with the extract only of the Hop, leaving out the substance; a simple method of giving new Beer all the qualities of age, thereby rendering it fit for the Bottle before it is three weeks old; a simple method of preventing Beer bursting the Bottle; an economical mode of constructing Vats above ground, possessing the temperature of the best Cellars, and thus rendered fireproof; an economical mode by which every Housekeeper may brew his own Beer; a method of brewing good Beer from Bran and Shorts, and of preserving it; the Bordeaux method of making and preparing Claret Wine for shipping, which may be successfully applied to the vines of this country, particularly those of Kaskaskias; the best method and season for malting Indian Corn, from which alone good Beer can be made, a process highly important to Brewers; the best mode of raising Hops; the best mode of preparing Seed Barley for sowing; best construction of Breweries and Malt Houses in this country; the French mode of tanning the heaviest Soal Leather in twenty-one days, and Calf Skins in three or four--highly important. By Joseph Coppinger, Practical Brewer." In conformity to the act of the Congress of the United States, entitled "An act for the encouragement of learning, by securing the copies of maps, charts, and books to the authors and proprietors of such copies, during the times therein mentioned;" and also to an act entitled "an act, supplementary to an act, entitled an act for the encouragement of learning, by securing the copies of maps, charts, and books, to the authors and proprietors of such copies, during the times therein mentioned, and extending the benefits thereof to the arts of designing, engraving, and etching historical and other prints." THERON RUDD, Clerk of the Southern District of New-York. ADVERTISEMENT. Since writing the Preface, I have been induced to make an addition to this little work, in order to increase its usefulness, by giving the French mode of tanning, as practised by the famous Mr. Seguine. Of such importance did the Academy of Arts and Sciences at Paris consider this improvement, that they thought it worth while to appoint a committee of their own members to go down to one of the provinces where this gentleman resides, and there, on the spot, superintend his operations, which they did with minute attention; and it is from the journal of their reports to the academy, that the different processes of tanning leather in this ingenious artist's way are here given; an improvement that can, no doubt, be successfully applied to that important manufacture in this country, affording the tanner the opportunity of turning his capital twelve or fourteen times in a year, instead of once. This single advantage alone so forcibly recommends its adoption, particularly in a country like ours, where capital is scarce, that further comment is unnecessary. I have also added the Bordeaux method of making and preparing claret wine for shipping, as practised in that city and its vicinity; which practice may possibly hereafter be successfully applied to the red wines of this country. The more so, when it is known that in the reign of Louis XVI., the merchants of Bordeaux presented a memorial to that monarch, praying him to put a stop to the importation of the wines of Kaskaskias into France, as likely, if permitted, to be injurious to the trade of Bordeaux. There was at that time a College of Jesuits established in that country, the superiors of which caused the wine to be cultivated with great success, and quantities of it were at that time sent to France. As that territory is now in our possession, and its soil and climate peculiarly favourable to the growth of the grape, which is indigenous there, may it not be an object well worth the attention of our government, to encourage and improve the growth of the wine in that section of the union; which wise measure would, probably, in a few years, supply our own consumption, and leave a considerable surplus for exportation. To offer an apology for giving these subjects a place in this publication, seems wholly unnecessary, when their importance is considered. PREFACE. Brewing, in every country, whose soil and climate are congenial to the production of the raw materials, should be ranked among the first objects of its domestic and political economy. If any person doubt the truth of this position, I have only to request him to cast an eye on England, where the brewing capital is estimated at more than fifteen millions sterling; and the gross annual revenue, arising from this capital, at seven million five hundred thousand pounds sterling, including the hop, malt, and extract duties. Notwithstanding this enormous excise of 50 per cent. on the brewing capital, what immense fortunes have been made, and are daily making, in that country, as well as in Ireland and Scotland, by the intelligent and judicious practice of this _more than useful art_. Yet how much stronger inducements for similar establishments in this country, where we have no duty on the raw materials, or the extract;[1] and where the important article of hops is raised in as high perfection as in any part of Europe, and often for one third of the price paid in England. But a still more important consideration is the health and morals of our population, which appears to be essentially connected with the progress of the brewing trade. In proof of this assertion, I will beg leave to state a well known fact; which is, that in proportion as the consumption of malt liquors have increased in our large towns and cities, in that proportion has the health of our fellow citizens improved, and epidemics and intermittents, become less frequent. The same observation holds good as respects the country, where it is well known that those families that brew their own beer, and make a free use of it through the summer are, in general, all healthy, and preserve their colour; whilst their less fortunate neighbours, who do not use beer at all, are devoured by fevers and intermittents. These facts will be less doubted, when it is known that yest, properly administered, has been found singularly successful in the cure of fevers. This the practice of the Rev. Doctor Townsend, in England, places beyond all doubt, where he states, that in fifty fever cases that occurred in his own parish, (some of which were of the most malignant kind,) he only missed a cure in two or three, by administering yest. Having considered the produce of the brewery as it is connected with health, we may, with equal propriety, say it is not less so with morals; and its encouragement and extension, as an object of great national importance, cannot be too strongly recommended, as the most natural and effectual remedy to the too great use of ardent spirits, the baneful effects of which are too generally known, and too extensively felt, to need any particular description here. The farmer and the merchant will alike find their account in encouraging and improving the produce of the brewery. The farmer can raise no crop that will pay him better than hops; as, under proper management, he may reasonably expect to clear, of a good year, one hundred dollars per acre. Barley will also prove a good crop, if proper attention be paid to seed, soil, and time of sowing. The merchant will alike find his account in encouraging the brewery, from the many advantages derivable from an extensive export of its produce to the East and West Indies, South America, the Brazils, but particularly to Russia, where good beer is in great demand; large quantities are annually sent there from England, at a much higher rate, it may be presumed, than we could afford to supply them from this country. All these considerations united seem forcibly to recommend giving the breweries of the United States every possible encouragement and extension. Here, it is but justice to state, that the brewers of New-York deserve much credit for the high improvement they have made in the quality of their malt liquors within a few years, which seem to justify the hope that they will continue these advances to excellence, until they realise the opinion of Combrune and others, that it is possible to produce a "_malt wine_." [1] Save five per cent. on brewery sales--a war tax. A Malt House. B Kiln. C Dropping Room. D Mill House. E Brewery. F Working Store. G Vat House and Dry Store. H Bed Room. I Office. K Dwelling House. L Hop Room. M Stable. N Brewing Yard. O Cooper's Shed. P Steep.] THE AMERICAN PRACTICAL BREWER AND TANNER _The best position for placing a Brewery and Malt house, also the best aspect, with different arrangements of the Utensils._ Cleanliness being as essential in the brewery as in the dairy, it is of the greatest importance, never to lose sight of it in every part of the operations, and particularly in selecting the ground and soil to place a brewery on. The situation to be preferred should be an elevated one, and the soil either sand or gravel, as it is of great importance in the preservation of beer that the cellars be dry and sufficiently ventilated by windows properly disposed. If the cellars of the brewery be under ground, it would be very desirable to have them kept sweet and clean by properly constructed sewers, without which, pumping by a hand or a horse power is a poor substitute, as by this means (which we find too common in breweries) the washings of the cellars have time to become putrid, particularly in summer, emitting the most offensive and unwholesome effluvia, contaminating the atmosphere, and frequently endangering both the health and lives of the workmen. This is a serious evil, and should in all cases, as much as possible, be avoided. It is true, there are times, when a choice of situation cannot be made; in that case, circumstances must be submitted to, and people do the best they can. The cellars and coolers of the breweries in this country should have a northern aspect, and the cellars principally ventilated from east to west. The windows on the south side of cellars should be always close shut in summer, and only occasionally opened in winter; the floors of cellars should be paved with either tile or brick, these being more susceptible of being kept clean than either pavement or flags, and not so subject to get out of order. Supposing the brewery to have all its cellars above ground, which I conceive to be not only practicable, but, in many cases, preferable to having them under, as more economical, and more cleanly, particularly where vats for keeping strong beer are constructed on the plan herein after recommended, in which it is expected the temperature necessary for keeping beer will be as securely preserved above, as under ground, and the erections so constructed, as not only to be air, but fire proof. (See description of these vats.) _A description of the form and plan of a Brewery, distribution of the Vessels, the most judicious and convenient manner of placing them, with a view to economy, cleanliness, and effect._ The best plan of a well-constructed brewery I conceive to be that of a hollow, or oblong square, where all is enclosed by one or two gateways, (the latter the most complete,) parallel to each other. The first gateway, forming the brewery entrance, to pass through the dwelling house; the second, or corresponding gateway, to pass through the opposite side of the square, into an outer yard, well enclosed with walls and sheds, containing cooper's shop, &c. where all the empty casks might be securely preserved from the injury of wind and weather. This yard should be further sufficiently large to afford room for a hay reek, firewood, dung, &c. The brewery office should be placed in the passage of the outer gateway, so that every thing going in and out might be seen by those who are in the office. The dwelling house, vat house, and working store, to form one side of the brewery. The malt house, another. The kiln house, dropping room, and stable, a third side. The brewery, mill house, and hop room, to form the fourth side; thus completed, it would form a square, and afford security to whatever was contained within it, when the gates are locked. The sky cooler is, generally, the most elevated vessel in the brewery, and when properly constructed, is of great importance in facilitating both brewing and malting operations, as it usually supplies the whole quantity of water wanted in both. It commands the copper, and, of course, all the other vessels of the brewery: it may be so constructed as to form a complete roof to the mill loft, and in that situation be most conveniently placed for being filled from the water cistern, which should be placed contiguous to the mill walk, and so raised to the sky cooler by one or more pumps worked by the mill, with a one, two, or three horse power, according to the length of the lever, and the diameter of the mill. Sky, or water coolers, in general, are square vessels, made of the best two inch pine plank, properly jointed, from twenty to twenty-five feet square, laid on strong joists sufficiently close, and trunneled down (after pressing) with wooden trunnels from end to end, to prevent starting or warping; the joists are supported by a couple of strong beams, equally spaced; the sides of these coolers are generally raised from eighteen inches to two feet; in Europe they are generally leaded on their inside, but this expense may be saved, if they are properly made at first, and afterwards kept constantly full of water. In constructing these coolers, all the joints should be paid with white paint before laying, and the sides bolted, and screwed down; the better and easier to effect which, the thickness of the sides may be three inches after the saw; there should be a roofing all round the sides, to protect them from the weather; the bottom of the sky cooler should command the copper back, which should be made to form the cover of the copper, and to hold a complete charge of the same. These vessels, when properly constructed, are extremely useful in preventing waste and accidents by boiling over, also affording to the brewer, the opportunity of boiling his wort as fiercely as he pleases--a very important advantage in brewing porter and strong beer. A description of this back is not necessary, as every set cooper, who knows his business, is well acquainted with the proper construction of this vessel. The stuff it is made of should be two inches thick, well seasoned, and of the best pine plank. Thus placed on the copper, it should form a complete cover, water and steam tight, so that when the copper boils over, it will run into the back, and return again by a plug hole into the copper. The copper cock should be sufficiently elevated to command the hop cooler; the latter the wort coolers, No. 1 and 2. By thus running the worts from one cooler to another, you afford them the opportunity of depositing in each their feculencies, and coming nearly fine to the fermenting tuns, which should be sufficiently elevated above the troughs and casks to be filled, so that the operation of cleansing may be easily performed by one or more leaders, to communicate with a two or three piped tun dish, capable of filling two or three casks at a time. The mill stones, or metal rollers, should be sufficiently elevated to grind into the malt bin, placed over the mash tun, which bin should be sufficiently capacious to hold the whole grist of malt when ground; this bin is generally constructed in the form of a hopper, with a slide at the bottom, to let the malt into the mash tun when the water is ready, by being cooled down to its proper temperature. I would recommend making the mash tun shallow, so that the diameter shall be three times as long as the staff of the sides, above the false bottom. To the mash tun there should be a cover, in two or more pieces, according to size. The receiver, or underbank, which is placed under the mash tun, should be sufficiently elevated above ground, so as to enable the dirty or washing water to run off from its bottom by a plug hole. The fermenting tuns should be placed in a room where there is a fireplace, so as to raise the temperature in cold weather; each tun should be cribbed on its sides, with a stationary cover on the top. The cribs should be made to answer the sweep of the vessel, and to be put on or off as occasion, or the temperature of the season, may require. In one corner of the working store, I would recommend to have placed a set of drains, two in number, one over the other; the lower drain should be sufficiently elevated to get a bucket under it, so as to draw off its contents by a plug hole, placed at one corner of each drain. These drains will soon pay for themselves, by the quantity of yest that will be deposited on them, at each time of drawing them off, while the liquor will get fine, and may be applied in a variety of ways, to answer the purposes of the brewer, what in filling, starting in the tun, vatting, &c. _Malt House, the best construction of, with proper Barley Lofts, Dropping Room, and Flooring, how, and in what manner made, and best likely to last._ Malt houses intended to be annexed to breweries, should not be on a less scale than sixty feet long, by twenty-five feet wide. Unless there be a proper proportion of flooring to work the grain kindly and moderately, good malt is not to be expected. Two-floored houses are generally preferred to any other construction; would recommend placing the steep outside the house, to be communicated with from the lower floor by means of an arch way or window; the steep so placed should be covered with a tight roof; the best materials for making a steep are good brick, well grouted; the wall should be fourteen inches thick at least; this kind of steep will be found far superior to wood, as not liable to leak, or be worked on by rats; the sides and ends of this steep should be carefully plastered with tarrass mortar; the bottom may be laid with flag, tiles, or brick.[2] Two barley lofts, the whole length of the malt house, will be found highly convenient, as affording sufficient room to different large parcels of barley, and screening the same from loft to loft as it descends into the steep over wire screens; a contrivance I have found of great advantage in the malting operation, as finishing the cleaning of the barley before getting into the steep, a precaution that should never be omitted. The bottom of the screen should be cased with wood, communicating from loft to loft with a sack fastened to hooks at the lower end to receive all the dirt and screenings that may pass through the screens. The Dutch and German maltsters generally prefer having their lower or working floor under ground; but this I take to be a bad plan, unless in elevated situations, or where the soil is dry and gravelly; for if any spring of water or damp arises in the malt-house floor, or walls so placed, the injury to the malt is very great, and should be carefully guarded against. It is also very important to lay a solid foundation for your lower floor with stones, brick bats, or coarse gravel, which should be solidly compacted by ramming for the whole length, then levelled off by stakes, with a ten-foot level, to the thickness you would wish to give your floor--say three or four inches: the former thickness, say three inches, will be found sufficient. Lay your first coat on two inches thick with hair mortar; when this coat becomes sufficiently stiff, which will happen within twenty-four hours, you are to begin to lay your second or last coat of one inch thick over the first, to be prepared as follows: Take Roche, or unslaked lime, one part, by measure; fine pit sand, one part; clinker, or forge dust, finely powdered, two parts; clay or lome, by measure also, one part: let these different ingredients (taking the precaution of first slaking the Roche lime) be well mixed together, and then screened by a wire screen, carefully keeping out of the mixture all lumps and stones; the whole may be then worked up with a due proportion of water, observing that this kind of mortar cannot be too much worked or mixed together, nor too little wetted, just sufficient to work freely with the plastering trowel; the whole floor should, if possible, be laid in one day, and for this purpose several hands should be employed; in which case it will dry more equally and firmly. As soon as the floor begins to set, and that it will bear a board on it, without sinking in, you should begin to pound it in all directions, from end to end, with pounders made of two-inch plank, sixteen inches long, and from nine to twelve inches wide, with a long handle reaching breast high, and to be placed in the middle of this board; thus the operation of pounding will proceed without stooping or much labour. One or two men, with plastering trowels, should follow the pounders, wetting it with skimmed milk as they go, and set the floor as even and close as possible. If these two operations be well conducted there will not be found a single crack in the whole floor from end to end, which is of great importance to secure the making of good malt. Each loft should have uprights under the centre of all the beams from end to end of the house; this precaution is necessary to prevent the swagging or cracking of the upper floor. Trap doors should be placed at proper distances in the upper malt-house floor, to facilitate the shovelling of the couches from the lower to the upper floor. A well constructed kiln is of great importance to insure a successful result to the malting operation, and if large enough to dry off each steep at _one cast_ so much the better. The most approved covering for malt kilns in England (although not the most economical) is hair cloth, as it is asserted, it dries the palest and sweetest malt. Many prefer tiles, as less expensive and more lasting; others dry on boarded floors, and if this construction be well managed, I take it to be as good as any, and much cheaper than either tiles or hair cloth. (See description page 23.) The dropping room for receiving the malt as it comes off the kiln may be constructed different ways; but I take it that a ground floor covered with a two inch plank well jointed, and properly laid, is preferable to a loft for keeping malt, and in this situation might be heaped to any depth without injury or danger of breaking down. Malt thus kept, if well dried before coming off the kiln, is never in danger of heating or getting slack. The common mode of keeping malt is in bins situated on upper lofts, often injured by leaks from the roof, and at all times liable to the depredations of rats, which in the other way can be effectually guarded against, and is a highly important object of precaution to be taken by the brewer. Should weevils at any time get into, or generate in your malt, which is common when held over beyond twelve or eighteen months, the simplest and easiest way of getting rid of them, is to place four or five lobsters on your heap of malt, the smell of which will soon compel the weevils to quit the malt, and take refuge on the walls, from which they can be swept with a broom into a sheet or table cloth laid on the malt, and so taken off. It is asserted, that by this simple contrivance not one weevil will remain in the heap. Malt intended for brewing should be always screened before grinding; and for this purpose it is a good contrivance to screen it by means of the horse mill, as it runs from the hopper to the rollers or stones to be ground, the expense of which apparatus is comparatively nothing when compared to the advantages arising from it. [2] By some this construction of a steep may be thought too dear; in that case, a rough wooden one may be substituted, which, instead of placing outside the house, I would place on the upper floor of the malt house, so as to afford the opportunity of getting down its contents to the lower floor by means of a plug hole, which will save the labour of shovelling; but in summer, when this steep is not employed, it should be filled with lime water to prevent leaking, and to keep it sweet. _Wooden Kilns, how constructed._ The best form for these kilns is the circular. I will suppose the diameter sixteen feet; you construct your fire-place suitably to the burning of wood at about ten feet outside your kiln house, sufficiently elevated on iron bars to secure the draft of the fire place, from which runs a proportionate sized flue into the kiln, communicating with a circular flue which is close covered at top, and rounds the kiln on the inside at the distance of two feet from the wall; on both sides of this circular flue holes are left, at the distance of twelve or sixteen inches apart, on both sides, to let out the smoke and heat; the platform or floor of this kiln is raised about four or five feet above the top of the flue, and is made of three quarter inch boards, tongued and grooved, supported by joists two inches broad, and nine inches deep, placed at proportioned distances, to give solidity to the floor. The floor or platform of this kiln should be carefully laid, and well nailed; in this floor should be placed a wooden chimney, nine inches square, on the most convenient part of the inside next the wall, with a wooden register at a convenient distance: this chimney is intended to let off the great smoke that arises in the kiln at first lighting fire, particularly if the wood be moist or green. When this has gone off, and the fire burns clear, the register may be shut within a few inches, in order to keep up a small draft. It would have been proper to state that joists, intended to support the floor of this kiln, should be levelled off to one inch, top and bottom, so as give the fire a better chance to act upon the malt; these joists should be further paid as soon as, or before, laying down, with a strong solution of alum water; as also the bottom face of the boards laid on them, which should be first planed; the inside of the chimney and register should be also paid with the alum solution. On the top of the kiln should be placed a ventilator to draw off the steam of the malt, this may be done by means of a loover or cow; the latter turns with the wind, the former is stationary. There should be skirting boards, nine inches deep, to lie close to the floor and walls of the kiln, plastered with hair mortar on the top. This construction of kiln has been introduced by the Dutch, and will be found the most economical of any, joined to the peculiar advantage of being capable of drying malt with any kind of fuel, without danger of communicating any sort of bad flavour to the grain, while the heat can be securely raised to 120 degrees without any danger of ignition or burning; a higher heat is not wanted to dry pale malt. Of this, however, I have some doubts, as wood is a non-conductor of heat, and possibly is not susceptible of transmitting such a heat to the malt without danger of ignition. I should think that thin metal plates, one foot square, cast so as to lap on each other, or tiles, of the same make or form, would be a better covering; they certainly would convey the heat more rapidly and securely to the malt or grain intended to be dried on it, never requiring less fuel than the wooden covering, and precluding all danger of fire. A A A A A ground section of the vats. B the section of elevation.] _A new and economical construction of Vats for keeping Beer, which, in this way, may be rendered fire proof, whilst, at the same time, it secures a temperature for the liquor equal, it is expected to the best vaults: it further affords the convenience of having them above ground._ These vats may be constructed in different forms, either square, oval, or round; the latter I should prefer, as stronger, and less liable to leak. These circular vats, to save expense, may be bound with wood hoops instead of iron ones the splay to be given them as little as possible barely sufficient to have the hoops tight, and the vessel staunch. The bottoms of these vats should be elevated at least three and a half, or four feet from the ground, and solidly bedded in clay, earth, or sand; the clay, if convenient, to be preferred. As the earth rises, at every five or six inches, around these vats, it should be firmly pounded down and compressed, as in the case of tanners' vats; and this mode of surrounding the vats with dry earth well pounded and rammed is continued to the top; a stout, close, well-fitted cover of two inch plank is then placed on each vat, with a hole sixteen inches square, to let a man down occasionally; this hole should have a short trunk of an inch and a half plank firmly nailed to its sides, and about fourteen inches high; then a covering of earth, twelve inches deep, should be placed all over the tops of these vats, and this earth well rammed and compacted together; and when levelled off, covered with composition or a floor of tiles. Each of the trap doors should have a well-fitted, wooden cover on the top, with a ring of iron in the centre; this cover should be made fire proof on the outside. The brick wall in front of these vats need not, I apprehend, exceed fourteen inches thick, if of brick, just sufficient to resist the force of pressure from ramming the clay; vats thus placed, with their contents, may be considered fire proof, and possessing as cool a temperature as if placed fifteen feet under ground; joined to this, they will last six times as long as those in cellars or vaults, although bound in iron, at a considerable higher expense. Two ranges of these vats may be placed in one house, leaving a sufficient space for a passage in the centre, with a window at each end to light it. I have never before either heard or read of this construction; but I have little hesitation in saying it will in many cases be found preferable to the present mode of placing vats--it being more convenient, cleanly, economical, and secure, and, to all intents and purposes, as effectual in point of temperature as those expensively placed deep under ground. Under the inside of the head of these vats, and across the joints, should run a piece of scantling six inches wide, and four inches deep, with an upright of the same dimensions in the centre, in order to support the covering on the head, and to prevent sinking, or swagging, from the weight of the covering that will be necessarily placed over them, which will be from six to ten inches thick. _Grinding, how substituted for._ Malt, for brewing, may be prepared in three different ways, by grinding, bruising, or pounding; modern practice, however, almost universally gives the preference to bruising between metal rollers. This preference, where malt is of the very first quality, may be justified; but where it is of an inferior quality, which is but too generally the case, grinding with stones is preferable, as more capable of producing a fine grist, which, with indifferent malt, is important, as it will always produce a richer extract, by being finely, rather than coarsely ground; and it is more soluble in water of suitable temperature than that malt which is only bruised or cracked, and for this simple reason, that all imperfect-made malt has a great proportion of its bulk unmalted, and, of course, in a crude hard state, which will partially dissolve in water if ground fine, but will not dissolve at all if only cracked or bruised. A further object of the brewer's attention should be to prevent the dispersion, or waste, of the finer parts of the malt, so apt to fly off in the grinding, if not prevented by having the malt bin close covered, as well as the spout leading into it from the stones; trifling as this precaution may seem, it is well worth the brewer's attention. Here it may not be improper to observe, that in all cases of horse, or cattle mills, where the shaft of the main wheel is perpendicular, no better ingredient can be placed in the chamber of the lower box than quick silver, which is far superior to oil or grease, and will not require renewing for a long time. The brass of a mill, managed in this way, might be expected to last twenty years, and the movement smoother and easier. This economical substitute for oil and grease can, with equal advantage, be applied to water mills, whether their shafts be horizontal or perpendicular; in a word, to all kinds of machinery, where the preservation of the gudgeons and brasses are an object. _Malting._ The production of good malt is, without question, the key-stone of the arch of brewing; therefore the brewer's attention should be invariably directed to this point, as the most difficult and important part of his operations. The process of making malt is an artificial or forced vegetation, in which, the nearer we approach nature in her ordinary progress, the more certainly shall we arrive at the perfection of which the subject is capable. The farmer prefers a dry season to sow his small grain, that the common moisture of the earth may but gently insinuate itself into the pores of the grain, and thence gradually dispose it for the reception of the future shower, and the action of vegetation. The maltster cannot proceed by such slow degrees, but makes an immersion in water a substitute for the moisture of the earth, where a few hours infusion is equal to many days employed in the ordinary course of vegetation, and the grain is accordingly removed as soon as it appears fully saturated, lest a solution, and, consequently, a destruction of some of its parts should be the effect of a longer continuance in water, instead of that separation, which is begun by the introduction of watery particles into the body. Were it to be spread thin after this removal, it would become dry, and no vegetation would ensue; but being thrown into the couch, a kind of vegetative fermentation commences, which generates heat, and produces the first appearance of a vegetation. This state of the barley is nearly the same with that of many days continuance in the earth after sowing, but being in so large a body, it requires occasionally to be turned over and spread thinner; the former, to give the outward parts of the heap their share of the acquired warmth and moisture, both of which are lessened by exposure to the air; the latter, to prevent the progress of the vegetative to the putrefactive fermentation, which would be the consequence of suffering it to proceed beyond a certain degree. To supply the moisture thus continually decreasing by evaporation and consumption, an occasional, but sparing, sprinkling of water should be given to the floor, to recruit the languishing powers of vegetation, and imitate the shower upon the cornfield; but this should not be too often repeated; for, as in the field, too much rain, and too little sun, produces rank stems and thin ears, so here would too much water, and, of course, too little dry warmth, accelerate the growth of the malt, so as to occasion the extraction and loss of such of its valuable parts as, by a slower process, would have been duly separated and left behind. By the slow mode of conducting vegetation here recommended, an actual and minute separation of the parts takes place; the germination of the radicles and acrospire carries off the cohesive properties of the barley, thereby contributing to the preparation of the saccharine matter, which it has no tendency to extract, or otherwise injure, but to increase and meliorate, so long as the acrospire is confined within the husk; and by as much as it is wanting of the end of the grain, by so much does the malt fall short of perfection; and in proportion as it is advanced beyond, is that purpose defeated. This is very evident to the most common observation, on examining a kernel of malt, in the different stages of its progress. When the acrospire has shot but half the length of the grain, the lower part only is converted into that mellow saccharine flour we are solicitous of, whilst the other half exhibits no other signs of it than the whole kernel did at its first germination: let it advance to two thirds of the length, and the lower end will not only have increased its saccharine flavour, but will have proportionably extended its bulk, so as to have left one third part unmalted. This, or even less than this, is contended for by many maltsters, as a sufficient advance of the acrospire, which, they say, has done its business, so soon as it has passed the middle of the kernel. But we need seek no further for their conviction of error, than the examination here alluded to. Let the kernel be slit down the middle, and tasted at either end whilst green, or let the effects of mastication be tried when it is dried off; when the former will be found to exhibit the appearances just mentioned, the latter to discover the unwrought parts of the grain, in a stony hardness, which has no other effect in the mash tun, than that of imbibing a large proportion of the liquor, and contributing to the retention of those saccharine parts of the malt which are in contact with it; whence it is a rational inference, that three bushels of malt, imperfect in their proportion, are equal but to two of that which is carried to its utmost perfection. By this is meant the farthest advance of the acrospire, when it is just bursting from its confinement, before it has effected its enlargement. The kernel is then uniform in its internal appearance, and of a rich sweetness, in flavour equal to any thing we can conceive obtainable from imperfect vegetation. If the acrospire be suffered to proceed, the mealy substance melts into a liquid sweet, which soon passes into the blade, and leaves the husk entirely exhausted. The sweet thus produced by the infant efforts of vegetation, and lost by its more powerful action, revives, and makes a second appearance in the stem, but is then too much dispersed and altered in its form to answer any of the known purposes of art. The periods of its perfect appearance are in both cases remarkably critical. It is at first perfect at the instant the kernel is going to send forth the acrospire, and form itself into the future blade; it is again discovered perfect when the ear is labouring at its extrication, and hastening the production of the yet unformed kernels; in this it appears, the medium of nature's chemistry, equally employed by her in her mutation of the kernel into the blade, and her formation thus of other kernels, by which she effects the completion of that circle to which the operations of the vegetable world are limited. Were we to inquire by what means the same barley, with the same treatment, produces unequal portions of the saccharine matter in different situations, we should perhaps find it principally owing to the different qualities of the water used in malting, some of which are so much better suited to the quality of the grain than others, that the difference is truly astonishing. Hard water is very unfit for every purpose of vegetation, and soft will vary its effects according to the predominating quality of its impregnations. Pure elementary water is in itself supposed to be only the vehicle of the nutriment of plants, entering at the capillary tubes of the roots rising into the body, and here depositing its acquired virtues, perspiring by innumerable fine pores at the surface, and thence evaporating by the purest distillation into the open atmosphere, where it begins anew its rounds of collecting fresh properties, in order to its preparation for fresh service. This theory leads us to the consideration of an attempt to increase the natural quantity of the saccharum of malt by adventitious means; but it must be observed, on this occasion, that no addition to water will rise into the vessels of plants, but such as will pass the filter, the pores of which appearing somewhat similar to the fine strainers of absorbing vessels employed by nature in her nicer operations; we by analogy conclude, that properties so intimately blended with water as to pass the one, will enter and unite with the economy of the other, and vice versa. Supposing the malt to have obtained its utmost perfection, according to the criterion here inculcated, to prevent its further progress, and secure it in that state, we are to call in the assistance of a heat, sufficient to destroy the action of vegetation, by evaporating every particle of water, and thence leaving it in a state of preservation fit for the present or future purpose of the brewer. Thus having all its moisture extracted, and being by the previous process deprived of its cohesive property, the body of the grain is left a mere lump of flour, so easily divisible that, the husk being taken off, a mark may be made with the kernel, as with a piece of soft chalk. The extractable qualities of this flour are saccharum, closely united with a large quantity of the farinaceous mucilage peculiar to bread corn, and a small portion of oil enveloped by a fine earthy substance, the whole readily yielding to the impression of water, applied at different times, and different degrees of heat, and each part predominating in proportion to the time and manner of its application. In the curing of malt, as nothing more is requisite than a total extrication of every watery particle, if we had in the season proper for malting a sun heat sufficient to produce perfect dryness, it were practicable to produce beer nearly colourless; but that being wanting, and the force of custom having made it necessary to give our beers various tinctures and qualities resulting from fire, for the accommodation of various tastes, we are necessitated to apply such heats in the drying as shall not only answer the purpose of preservation, but give the complexion and property required; to effect this with certainty, and precision, the introduction of the thermometer is necessary, but the real advantages of its application are only to be known from experiment, on account of the different construction of different kilns, the irregularity of the heat in different parts of the same kiln, the depth of the malt, the distance of the bulb of the thermometer from the floor; for though similar heats will produce similar effects in the same situation, yet the distribution of heat in every kiln is so irregular, that the medium spot for the local situation of the thermometer as a standard, cannot be easily fixed for ascertaining effects upon the whole. That done, the several degrees, necessary for the purposes of porter, amber, pale beers, &c. are easily discovered to the utmost exactness, and become the certain rule of future practice. Though custom has laid this arbitrary injunction of variety on our malt liquors, it may not be amiss to intimate the losses we often sustain, and the inconvenience we combat in our obedience to her mandates. The further we pursue the deeper tints of colour by an increase of heat, beyond that which simple preservation requires the more we injure the valuable qualities of the malt. It is well known that scorched oils turn black, and that calcined sugar assumes the same complexion; similar effects are producible in malts, in proportion to the increase of heat, or the time of their continuing exposed to it. The parts of the whole being so intimately united by nature, an injury cannot be done to the one without affecting the other; accordingly we find that such parts of the subject as might have been severally extracted for the purpose of a more intimate union by fermentation, are, by great heat in curing, burned and blended so effectually together, that all discrimination is lost--the unfermentable are extracted with the fermentable, the integrant with the constituent, to the very great loss of spirituosity and transparency. In paler malts the extracting liquor produces a separation, which cannot be effected in brown, where the parts are so incorporated, that unless the brewer is very acquainted with their several qualities and attachments, he will bring over with the burned mixture of saccharine and mucilaginous principles, such an abundance of the scorched oils, as no fermentation can attenuate, no precipitants remove; for being themselves impediments to the action of fermentation, they lessen its efficacy; and being of the same specific gravity with the beer, they remain suspended in, and incorporated with, the body of it--an offence to the eye, and nausea to the palate, to the latest period. From this account it is evident the drying of malt is an article of the utmost consequence concerning the proper degree of heat to be employed for this purpose. Mr. Combrune has related some experiments made in an earthen pan, of about two feet diameter, and three inches deep, in which was put as much of the palest malts, very unequally grown, as filled it to the brim. This being placed over a charcoal fire, in a small stove, and kept continually stirred from bottom to top, exhibited different changes according to the degrees of heat employed on the whole. He concludes, that true germinated malts are charred in heats between one hundred and seventy-five, and one hundred and eighty degrees, and that as these correspond to the degrees in which pure alcohol, or the finest spirit of the grain itself boils, or disengages itself therefrom, they may point out to us the reason of barley being the fittest grain for the purpose of brewing. From these experiments, Mr. Combrune has constructed a table of the different degrees of the dryness of malt, with the colour occasioned by the difference of heat. Thus, malt exposed to one hundred and nineteen degrees, is white; to one hundred and twenty-four, cream colour; one hundred and twenty-nine, light yellow; one hundred and thirty-four, amber colour; one hundred and thirty-eight, brown; one hundred and fifty-two, high brown; one hundred and fifty-seven, brown, inclining to black; one hundred and sixty-two, high brown speckled with black; one hundred and seventy-one, colour of burned coffee; one hundred and seventy-six, black. This account not only shows us how to judge of the dryness of malt by its colour; but also, when grist is composed of several kinds of malt, what effect the whole will have when blended together by extraction. Experience proves that the less heat we employ in drying malt, the shorter time will be required before the beer that is brewed from it is fit to drink, and this will be according to the following table: _A table giving the heats of different coloured malts, and the time beer takes to ripen when brewed from them._ 124 Degrees 1 Month. \| 138 Degrees 6 Months. \| 152 Degrees 15 Months. 130 Degrees 3 Months. \| 143 Degrees 7 Months. \| 157 Degrees 20 Months. 134 Degrees 4 Months. \| 148 Degrees 10 Months. \| 162 Degrees 32 Months. _The plain practical process of Malting pale Malt, according to the most approved English method._ Suppose you are about to malt spring or summer barley, and that your steep contains sixty bushels. The time generally allowed for this kind of grain to remain in steep is from forty to forty-eight hours, taking care to give two waters; the first water is to continue on the grain twenty-four hours, then run off, and fresh water put on. This precaution is essentially necessary, in order to make clean bright malt, and should never be omitted. It is further right, at each watering, to skim off the surface of the water the light grain, chaff, and seed weeds, that are found floating on it; all this kind of trash, when suffered to remain in the steep, is a real injury to the malt, and considerably depreciates its value when offered for sale, and not less so when brewed. The depth of water over the barley in the steep need not exceed two or three inches, but should not be less. When the barley has remained in steep the necessary time, the water is let off by a plug hole at the bottom of the steep, with a strainer on the inside of the hole; when the barley is thus sufficiently strained, it should be let down by a plug hole in the bottom of the steep into the couch frame on the lower floor, (or adjoining to it, which would be the better construction,) which is no more than a square or oblong inclosure of inch and a half boards ledged together, and about two feet deep, of sufficient capacity to hold the contents of the steep, and so placed, in upright grooves, as to ship and unship in this frame. The steeped barley is to remain for twenty-four hours in the frame, when it should be broke out, and carefully turned from the bottom to the top, nearly of the same thickness it was in the frame, not less than sixteen or eighteen inches, where it should be suffered to remain twenty-four hours longer, or until the germination begins to appear: but this will be always shorter or longer, according to the temperature of the season, and is generally ascertained by sinking your hand towards the middle of the heap, and bringing up a handful of the grain, which, if regularly germinated, will make its appearance in every grain of barley, by appearing white at one end; at this stage of the process, (supposing the temperature of your malt house sixty degrees,) the heap should be extended on the floor, to the thickness of eight inches; after which it should be turned three or four times a day, according to the season, and the progress of vegetation; gradually reducing the thickness of the couch to four or five inches; but it should be remarked, that as soon as the root begins to dry and wither, the watering pot is to be used; the judicious management of which is one of the most important parts of the process of malting, and should be paid particular attention to. One watering, well applied, will, in most cases, answer the purpose. Two thirds of the whole quantity of water should be given to the upper surface of the couch, then turn it, and give the remaining third of the water to the couch when turned. The whole quantity of water to be used for sixty bushels of American spring barley, may be averaged at fifty-four gallons; this quantity will, consequently, allow thirty-six gallons to be as evenly distributed over the surface of the couch for the first water, as possible; the remaining eighteen gallons to be put on in the same way: when the couch is turned after this last watering, the whole couch should be turned back again; thus, in every turning, the bottom and top should always exchange places. In this stage of the process, care should be taken to turn the couch frequently, to prevent the growth of the root, in order to give the greater facility to the growth of the blade, it being essentially requisite to keep that of the root stationary, to prevent a waste of strength in the grain. Three or four days after watering, is generally found a sufficient time for the blade to grow fully up to the end of the grain; farther than which it should not be suffered to proceed. The couch should be now checked in its growth, and thrown on the second or withering floor, where it should be laid thin, and frequently turned; this continued operation will bring it dry and sweet to the kiln, to which it may be committed without further delay. Although the common practice is to throw it up into what is commonly termed a sweet-heap, and so remain from twelve to twenty-four hours, or until you can hardly bear your hand in it; then, and not before, is it considered fit to go on the kiln. This is a practice that cannot be too much condemned, or too generally exploded, as producing the very worst consequences; a few of which I will mention. Green malt, thus treated, becomes in a manner decomposed; and beer brewed from such malt will never keep long, acquiring a disagreeable, nauseous flavour, rapidly tending to acidity, beside becoming unusually high coloured. Although the malt, before grinding, will have all the appearance of pale malt, this quality can be easily accounted for by the high heat the malt is suffered to acquire in the heap before putting it on the kiln. What I have here mentioned will, I trust, suffice to recommend a more judicious mode of practice. Forty-eight hours for malt to remain on the kiln is enough, as pale malt can be completely dried in that time, if frequently turned, and properly attended to. It is further worthy of remark, that barley malt should in no case exceed fifteen or sixteen days from the steep to the kiln, and is often more successfully effected in twelve or thirteen days. The common practice of maltsters is to allow twenty one days, which generally brings the green malt in a mouldy state to the kiln, to the great injury of flavour and preservation in beer brewed from such malts; whereas, the grain should be brought as sweet and dry as circumstances will allow of to this last and important operation of malting, every part of which requires minute and continued attention. When you suppose your malt sufficiently dry, make a round space in the centre of your kilncast by shovelling the malt to the extremities; after which, sweep this space, and shovel back again your malt from the walls and angles into it; make a round heap of the whole on the centre of your kiln, sweep your kiln all round the foot of your heap; so let it stand two hours, then throw it off; this last operation is performed to give every chance for equal drying. The practice of many maltsters is to take seventy two hours to dry their pale malt, keeping all the time a very slow and slack fire, this is another capital error, and should be corrected with the former ones. Various are the opinions entertained, as to the best mode of preserving malt after coming off the kiln: some are of opinion that the circumambient air should have a free access to it; this opinion, I admit, might have weight if such malt was to be immediately brewed; but where it is allowed to remain in heap for four or five months, and gradually become cool, the less air admitted to have access to it the better; this has been the practice and opinion of the most judicious maltsters I have been acquainted with, and, consequently, is what I would recommend, except in the case of immediate use, where exposure becomes necessary, particularly after grinding, as malt so treated will bear a higher liquor, and yield a more preserving extract. _Winter Barley._ To avoid useless and unnecessary repetitions, it is enough simply to state, that winter barley, being a weaker bodied grain than summer, requires less watering, consequently, a less time in steep, say 36 to 40 hours, and about 32 gallons of water to sixty bushels will be sufficient on the floor; the other treatment the same. _Oats the same_, with about 24 gallons of water on the floor, for sixty bushels, divided as directed in the case of summer and winter barley; the remaining part of the process the same. _Rye Malt._ Rye may be steeped 48 hours, with 48 gallons of water on the floor; the remainder of the process the same, quantity of grain sixty bushels. _Wheat._ The above time in steep, and same proportion of water on the floor, will answer to make wheat malt, suppose 60 bushels, varying somewhat according to season, the time of steeping, and bringing to the kiln; the remainder of the process the same. _Indian Corn Malt, a valuable auxiliary to Brewing materials._ This species of grain well managed, and made into malt, will be found alike useful to the brewer and distiller, but it is peculiarly adapted to the brewing of porter; further, it is known to possess more saccharine matter than any other grain used in either brewing or distilling, joined to the advantage of not interfering with the season for malting barley, as this should commence when the former ceases. The summer months are the fittest for malting this kind of grain, and can be only very defectively made at any other season, as it requires a high temperature to force germination, and cause it to give out all its sweet. The following process, it is expected, will be found to answer every purpose wished for: suppose your steep to contain sixty bushels, after you have levelled it off, let on your water as directed in malting barley; you should give fresh water to your steep at the end of twenty-four hours. If it is southern corn you are malting, it will require to remain in steep seventy-two hours in the whole; if it be northern corn, it will require ninety-six hours, there being a considerable difference in the density of these two kinds of grain; the hardest, of course, requires the most water; and, in all cases, the fresher Indian corn is from the cob the better it will malt. When you have accomplished the necessary time in your steep, you let off your water; and, when sufficiently drained, let it down in your couch frame, where it will require turning once in twelve hours, in order to keep it of equal temperature; the depth of the grain should be about two feet and a half in the frame; as it begins to germinate and grow, open your frame, and thin it down at every turning, until you reduce its thickness to six or seven inches; thus extending it on your lower floor, turning it more frequently, as the growth is rapid. The vegetation of the grain, together with the turning, will by this time make the watering pot necessary; the criterion by which you will judge of its fitness for the water, is as soon as you perceive the root or acrospire begins to wither. Two thirds of your water is to be distributed over the surface of your couch for the first watering, which will require thirty-two gallons, and when turned back again, sixteen gallons for the second watering, making in the whole forty-eight gallons of water to sixty bushels of corn. This water should be put on with a gardener's watering pot, as equally as possible. Supposing this pot to contain four gallons, it will make eight pots for the first watering, and four for the second. In this stage of the operation the turnings on the floor should be very frequent, in order to keep the grain cool, as the heat of the weather, at this season, will be sufficient to promote and perfect the vegetation. The second day after the first watering, if the blade is not sufficiently grown, water again, but in less quantity, say one half. It will be now four or five days more before the couch is ready for the kiln, which will be ascertained by the blade becoming the full length of the corn. After this it should be thrown on the upper floor, and suffered to wither for a couple of days, turning it frequently; by this time the blade will have a yellow appearance, the grain will become tender, and, if tasted, be found uncommonly sweet; in this state it may be committed to the kiln, and dried in the usual way. N. B. It will generally take ten days after it is out of the steep to perfect the malting of southern corn, and twelve days for northern. _Fermentation._ Notwithstanding that progress of improvement in the doctrine of fermentation has, in the last twenty years, far surpassed any thing in the same period that preceded it, we have still much to learn. Fermentation is the instrument or means which nature employs in the decomposition of vegetable and animal bodies, or reduction of them to their original elements, or first principles. Fermentation is, therefore, a spontaneous separation of the component parts of these bodies, and is one of those processes that is conducted by nature for their resolution, and the combination and fermentation of other bodies out of them; therefore, it is one of these operations in which nature is continually present, and going on before our eyes; this may be one reason that a very critical observance of it has escaped our attention. Fermentation brings us acquainted with this unerring axiom; that nothing in nature is lost; or that matter, of which all things are composed, is indestructible. For instance, the vinous process of fermentation, succeeded by distillation, produces ardent spirits, or alcohol, the elements of which are here described. If we pass this alcohol, or spirits of wine, through a glass, porcelain, or metallic tube, heated right hot, provided with a suitable condenser and apparatus to separate and contain the parts or products, it will be decomposed and resolved into its primitive elements, carbonic acid gas, or fixed air, and hydrogen gas, or inflammable air; the oxygen being decomposed and united with the oxygen, or vital air, into carbonic acid gas; the water of the spirit of wine being also decomposed, or resolved into its first principles as herein is stated, forms a part of the produce before mentioned. Hence spontaneous fermentation, vinous, acetous, and putrefactive, is the natural decomposition of animal and vegetable matters, to which a certain degree of fluidity is necessary; for where vegetable and animal substances are dry, as sugar and glue for instance, and are kept so, no fermentation of any kind succeeds. There can be no doubt that spontaneous fermentation first taught mankind the means of procuring wine and other agreeable beverage; observation and industry the means of making spirit and vinegar, the first of which is evidently the produce of art, combined with the operations of nature. With nature for our guide, and our own ingenuity, fermentation has been made subservient to the various products we now obtain from saccharine and fermentable matters, such as sugar, molasses, grain, with which we have made wine, spirits, bread, beer, malt, &c.; which last has much facilitated our practice in fermentation, but proved the tide-ending, or point of stagnation to its further improvement. Relying too much on malted grain in the operation of fermentation, we are presented with some of the most pleasing and instructive phenomena of nature; the resolutions and combinations that are formed during the process of the vinous and acetous stages of fermentation, are interesting, beyond comparison, to the brewer, malt and molasses distillers, vintager, cider and vinegar maker, &c. The elastic fluids and volatile principles that are extricated and escape, formerly so little attended to, are now better understood. The method of commodiously saving, and advantageously applying them, and other volatile products, to the improvement of the fermenting and other fluids, will, I hope, not only form a new era in the progress of fermenting, brewing, distilling, &c. but a new source of profit, that may, in time, lead to a recomposition of those elements from which they were produced, or, at least, the fermentation of vinous fluids, vinegar, spirit, &c. by resorting to an inexhaustible source supplied by nature, of these important materials, and their application to the uses that may be made of that abundance so easily procurable, and at present so unprofitably wasted. But to continue our views to the business immediately before us, let us begin with the several products, by stating that carbonic acid gas, or fixed air, is copiously extracted from fluids in a state of vinous fermentation, and sundry mineral and vegetable substances, easily procurable, for which we have the testimony of our own senses; the same may be said of hydrogen gas, oxygen gas, &c. Presuming these positions granted, let us make a short inquiry into the composition of vinous fluids, &c. Apprehending there are but few people to whom these observations will be useful, but what will allow that all vinous fluids, whether intended for beer, wine, cider, &c. are the produce of saccharine matter, or fermentable matter obtained from the sugar cane, grain, fruit, &c. and the part which art at present takes in this beautiful process of nature, is to facilitate her operations in proportion to observation and experience, in conformity to the object in view, in making wine, beer, cider, spirit, &c.; or, subsequent to the vinous, to forward the progress of the acetous fermentation for the production of vinegar. The saccharine or fermentable matter of vegetables, consists in what is chemically called hydrogen gas, or inflammable air; carbonic acid gas, or fixed air; oxygen gas, or vital air; which last forms nearly one third part of the whole atmosphere, circumvolving our globe in which we breathe; or, more exactly, thirty-seven parts of oxygen, and seventy-three of azotic gas, are the component parts of our atmosphere, except the small proportion of undecomposed carbonic acid gas there may be found in it. Beer, wine, cider, malt and molasses wash, and other product by distillation; spirit consists of these three elastic fluids or airs, in composition with various proportions of water. Water itself is a compound of vital and inflammable air; a proof of this, and of the indestructibility of matter, these two elastic fluids burned together, in certain proportions, and in a proper apparatus, reproduce water. By another chemical process, this very water is reducible to these two substances, vital and inflammable air; hence, we see, that all saccharine and fermentable matter, and their products, by fermentation, are composed of the same materials, and resolvable into the same elements. It is scarcely necessary to give any definition of spontaneous fermentation, after what has been said on the subject; if it was, I would say it is that tendency which all fermentable matter has to decomposition, attended with intestine motion or ebullition, when sufficiently diluted with water, under a certain temperature of the atmosphere, the rapidity of which motion is always accompanied by an increase of temperature, or the change to a greater degree of heat generated within the body of the fermenting fluid, in proportion to the rapidity or augmentation of motion or ebullition excited. Fermentation produced by the addition of yest, or any other suitable ferment, in a fluid duly prepared, is governed by the same laws, and under the same influence of temperature, except when it is accelerated or protracted by the management of the operator, or by the changes induced by the influence of the atmosphere, rendered more or less subservient to his purposes, and produces a similar kind of spirit by distillation, possessing in common the properties of vinous spirit, or is converted to vinegar by the subsequent process of acetous fermentation, but much more productive in quantity and quality, so as to answer commercial purposes. In both spontaneous and excited fermentation, there is a similar escape of a large quantity of elastic fluid, or carbonic acid gas, with a considerable proportion of spirit, and some of the water of the fermented fluid. This gas is known to form a considerable part of mucilaginous substances, as sugar, molasses, honey, malt, and other saccharine and fermentable matter. Although the doctrine of fermentation, as a science, does not enable us to alter the spontaneous course of nature; yet if, by the assistance of the instruments, and means recommended, we are enabled to foresee and provide for the changes induced by the alterations of the atmosphere, we can guard against the inconveniences in some cases, and make them subservient to our purpose in others; so as more securely to conduct the process in each to advantage; and that with unusual facility; complex as it at present appears: it will not only be a great improvement in the present mode of fermentation; but facilitate our progress to still greater improvements in the doctrine of fermentation. Therefore, the rule of our conduct, in these pursuits, should be to watch the operations of nature with the closest attention, and assist her when languid, and control her when too violent; that is, by spurring in one instance, and bridling in the other, and accurately and undeviatingly apply the means proposed in the manner recommended, until experience enables us to improve it; otherwise, we shall only admire, without improving or profiting by her choicest phenomena. The motions of the planets, perplexed and intricate as they must have appeared in the infancy of astronomy, are now calculated and known with ease and precision. Attenuation is a term not unaptly applied to fermentation, the property of attenuation being to divide, then dilute, and rarify thick, gross, viscid, and dense substances, in which some degree of fluidity is pre-supposed; it is, therefore, that kind of dilution or fluidity which is promoted by agitation, and very aptly applied to mark the progress of fermentation, which is itself the process of nature, for decomposing vegetable and animal substances under a convenient degree of fluidity; it exists in intestine motion, either spontaneous or excited, accompanied with heat, which, under certain limits, is proportioned to the vigour of the fermentation, which ends in the decomposition of one class of bodies, and the composition of another; and which may be instanced in the resolving saccharine substances into hydrogen, oxygen, and carbon, and the combining them into inflammable spirits, or alcohol, and inflammable acids or vinegar; to which may be added, the lower you attenuate, the lighter and more spiritous the fermenting fluid becomes; and that attenuation, which is the offspring of fermentation, like the parent process, has its bounds, and can only be conducted with certainty and advantage by the use of the hydrometer, thermometer, &c. In this only lies the difference between the old word fermentation, and the new word attenuation, every thing used as a ferment, or to promote fermentation, is attenuant. The tendency of the vinous process of fermentation is to evolve or disentangle the hydrogen of the fermenting fluid, and unite it, with the carbon and oxygen of the same fluid, into ardent spirit, wine, beer, or alcohol, which last is well known to be inflammable. The tendency of the acetous process of fermentation, is to involve or entangle the hydrogen and carbon of the fermented fluid, with a greater proportion of oxygen, into vinegar, which is uninflammable. The fixed air, or carbonic acid gas, so abundantly extricated during the vinous process of fermentation, which every one concerned in the process is presumed to be acquainted with, is either composed of hydrogen and oxygen, or is a composition of carbon and oxygen, on which philosophers are divided in opinion. As the result is the same with respect to the formation of wine, beer, and spirit, I shall enter into no controversial reasoning on this head, instead of which, I shall endeavour to point out the most effectual mode of saving and profitably applying it, and the other elements, in the composition of wine, beer, spirit, and acid. As in fermentation, spontaneous or excited, there is a sensible escape of carbonic acid gas, or fixed air, it may not be improper to note, that fermentable, or saccharine matter, consists of about twenty-eight pounds of carbon, eight pounds of hydrogen, and sixty-four pounds of oxygen, reducible into fixed, inflammable, and vital air, weighing one hundred subtile pounds in toto, or that every one hundred subtile pounds of saccharine matter consists of such proportions of these airs and gasses. Attenuation is the result of a due resolution of the fermentable matter produced by excited fermentation, which divides mucilages, resolves viscidities, breaks down cohesions, generates heat and motion, extricates the imprisoned gasses, and, by frequent commixture, promotes the action and re-action of the component particles on each other, and by continually exposing a fresh surface and opposition of matter, brings them within the sphere of each other's attraction. As their original attraction is weakened by heat and motion, their expansion is increased by repulsion; and as they revolve, and recede from each other in this way, they are fitted, by the change in their modification, to involve each other, and from new attractions combining with each other into new substances, according to affinity, under changes induced in their nature conducive to this end, which not being exactly known, cannot at present be fully defined. In every brewing, or preparation of saccharine fluid for fermentation, the following phenomena occur: first, _heat_ is either disengaged or fixed: secondly, an _elastic fluid_ is either formed or absorbed in a nascent state: these two indisputable facts form the uniform and invariable phenomena of fermentation, and may be admitted as an established _axiom_, that the proportions, extrication, and action of heat, with the fermentation and fixation of elastic fluids, during the process, are the foundation of the vinous products of the fermenting fluid. In conformity to so rational a theory, I have for many years regulated my practice, the result of which is the object of these papers. These, therefore, are the three great objects which should engage our attention; not only in fermentation, but in every similar process in chemistry, and are the fundamental principles of our doctrine. FERMENTATION being not only a decomposition of the fermentable matter, but of the water of the fluid also; and the fixed air formed during the process being composed of the hydrogen and oxygen of the fermentable matter, and the water of the fluid also, there is a perpetual decomposition and recomposition of that water, which gives fluidity to the whole mass, taking place during the continuance of the process, part of the hydrogen and oxygen of which escapes under the form of fixed air, for want of a proper substance being presented of affinity enough to absorb and combine with it into wine, beer, or spirit, or some other necessary assistance in heat, light, motion, oxygen, hydrogen, carbon, &c. or an intermedium to facilitate the formation of wine, beer, or spirit, in preference to fixed air. Fixed air, or carbonic acid gas, consists of about twenty-five parts of oxygen, and nine of carbon, devested of the mucilage and yest that rises with it. It should be recollected, that the decomposition of pyrites, the formation of nitre, respiration, fermentation, &c. are low degrees of combustion, and though it is the property of combustion to form fixed and phlogisticated airs, both the modes of doing it, and the quantity of the products, depend on the manner of oxygenating them in the changes brought about by the different modes of combustion, or fermentation in the vinous, acetous, and putrid process, which show the affinity between them. Fermentation is a subsequent _low combustion_ of the vegetable oxydes or grain, that has undergone a previous, but partial combustion, something like the slightly charring, or oxydating of wood or pit-coal, by which the oxygenation is incomplete in both, and rendered more complete in the former. An ultimate combustion of the fermentable matter employed, is found only in the putrid process of fermentation, which is a final or total decomposition of vegetable and animal substances, in the actual combustion or burning of wood, charcoal, or bones. In the vinous process we have seen the escape of carbonic acid gas; in the acetous process there is a great escape of azotic gas, or phlogisticated air, from the decomposition of the air of the atmosphere consumed in this process, which consists of about two-thirds of azotic gas, and one third of oxygen gas,[3] the oxygenous part being absorbed in the acetous process, and azotic set free with more or less hydrogen and acetic gas, proportioned to the existing heat. If the heat is beyond a certain degree, a portion of the ethereal part of the new-formed acid escapes also. [3] Twenty-seven parts of oxygen gas, and seventy-three of azotic gas. In the putrid process, the hydrogen escapes under the acriform shape of inflammable air and azotic gas, and nothing more remains than mere earth or water, or both, as the case may be, which is exactly similar to other combustions, of which nothing remains, (if we except phosphorus) but earth or ashes, with what small portion of alkaline or other salts they may contain. This alkaline matter being present during the formation of carbonic and azotic gas, absorbs, to saturation, a due proportion of them, and generates _tartar_. Experience has taught us the truth or justness of this definition, and though it has brought us acquainted with the results of those three stages of fermentation, combustion, or decomposition, we have certainly overlooked the means of applying them with all the advantage they admit of in the business which is the subject of these papers, and which a little time and close observation must convince us of; and how much has been hitherto lost, with the means of saving it in future, shall be presently explained, and particularly pointed out. In the prosecution of this design, where I may not be able to give an unexceptionable demonstration, I hope always to be provided with a practical proof, which may prove equally beneficial. Let us now see what passes in a state of low combustion, such as may be the result of fermentation in vegetables, arising from heat, moisture, and motion, when impacted together. The most obvious occurrence of this nature is found in new hay, which, under these circumstances, for want of care and attention, often spontaneously takes fire, particularly in wet seasons. Fermentation, being one of the lowest degrees of combustion, is here the spontaneous effect of the moist hay being impacted together, and not properly made, that is, without the superfluous juices being dried out of it, by which it retains a sufficient degree of fluidity or moisture to begin a fermentation, in which heat and motion are generated, and light, in a nascent state, extricated; these appearances accumulated and accelerated by incumbent pressure, the redundant moisture being soon exhausted, and the heat and motion increasing, the actual combustion of the mass takes place, which is much facilitated by a decomposition of the water of this moisture, and the air of the atmosphere, unavoidably insinuated between the interstices formed by the fibres of the hay, as they are impacted together into cocks, or stacks, breaks out into actual flame, or _light visible_. These are no novel appearances, but such as fall within the observation of every one; and the candid maltster will acknowledge, that from the same cause, though differently produced, similar effects may, and sometimes do, happen in the malt house, in the preparation of that modern article of luxury, by which we are enabled to make malt wine; and these instances are sufficient to prove fermentation to be a low degree of combustion, and to both simplify and explain the justness of this doctrine. The malting of corn is the first stage of vegetation, low combustion, and fermentation. From observation and reasoning on what passes before our eyes, we discover the low species of fermentation, in which the malting of corn consists, to be a low degree of combustion, which, for want of due attention, may break out into actual flame. We were always acquainted with the _effect_: now reasoning on the subject brings us to a knowledge of the cause. To any one well acquainted with the nature of fermentation, it must be manifest, that the malt distillers have paid more attention, and made greater progress in the improvement of the process than any other class of men interested in the success, though far from having arrived at their _ne plus ultra_. The introduction of raw or unmalted corn; the close compactness of their working tun, or fermenting backs; the order and progressive succession with which they conduct the process; and the pains they necessarily take to arrive at a perfect attenuation, by a long protracted fermentation, with the early conviction of a reward proportioned to their diligence, and the success attending their best endeavours, when not frustrated by intervening causes, must be stronger inducements with them to delight in this instructive process of nature's formation, than with the brewer, who has not these immediate tests to encourage his labours, which the others daily derive from distillation, and which so quickly and uniformly terminates their hazards and success. The principal object in their view being a high and deliberate attenuation, with a full vinosity, without any further regard to the quality or flavour of their mash, as the combination of these qualities alone produces the required strength, in the cleanest manner. The brewer's cares are many, and of longer duration: he is the vintager of our northern climates: his porter or ale should be an agreeable malt wine, suited to the palate of the district or neighbourhood he lives in, or, ultimately, to the taste of his customers. The time he has allotted himself for attenuation was first founded in error, derived from ignorance of the subject, and slavishly continued by that invincible tyrant, custom. Hurry marks the progress of his fermentation, which can only be corrected by his speedy mode of _cleansing_, and the consequent but necessary perishing of a part. He must begin with more accuracy at the mash tun than the malt distiller, as it is there he must not only regulate the strength, but, partially, the flavour and transparency of his malt wine. His object does not end with the malt distiller's, nor, like his, concentre in one focal point, the solution of the whole of the farina of the plant or grain employed, regardless of milkiness or transparency; he must carefully take the heats of his liquor, so as to solve and combine the qualities he has in view; which, if he misses in the first mash, is partly irremediable in the succeeding ones. His cares do not end here; independent of the minutiæ of fermentation and cleansing, he has the flavour, fining, and bringing forward of his _malt wines_, nearly as much as the strength, to consider and employ his attention. It will scarcely be supposed that I would make these observations merely with a view of drawing this comparison, though even it might throw some light on the subject, without an attempt at supplying the defects pointed out, and remedying the evils represented. When the carbonic acid gas, or fixed air, so often mentioned in these papers may be rendered subservient to part of the improvements I have in view, and which is the constant, abundant, and uniform result of low combustion, or vinous fermentation, in proportion of thirty-five pounds weight to every hundred of saccharine or fermentable matter, fermented in a due proportion of liquor, or water; from the decomposition of which last, and the absorption of its oxygen, it is principally obtained. We have previously seen that one hundred pounds of fermentable matter consists of eight pounds of hydrogen, twenty-eight of carbon, and sixty-four pounds of oxygen; we have also seen that about thirty-five pounds of carbon is extricated and detached from this quantity of fermentable matter, properly diluted in water during fermentation; allowing the usual quantity of spirit at the same time to be formed by the process of this superfluous carbon, (as it now appears) must come principally from that decomposition of the water of dilution, and not from saccharine matter employed, which contains altogether but twenty-eight pounds of carbon, the whole of which must necessarily go to the formation of the fifty-seven pounds of dry alcohol produced. But not to descend too deeply into particulars that might lead into discussions not absolutely necessary in this place, let us take the produce of ten gallons of ardent spirit, at one to ten over proof. We here find that much more carbon has been generated, and given to the atmosphere, than went to the composition of this quantity of spirit, independent of the large quantity of alcohol dissolved in, and carried off by it, in its flight as before observed. Allowing the average quantity of fermentable matter in a quarter of malt, barley, or other grain, to be only seventy-five pounds, then four quarters will be equal to three hundred subtile pounds of raw sugar; or eighty quarters of the one will be equal to six thousand pounds of the other, or three tuns weight of unadulterated molasses. If we estimate the superfluous carbonic acid gas of this quantity of materials at only twenty-eight pounds per hundred, that will be sixteen hundred and eighty pounds dissipated during the fermentation, which is a loss, on every brewing of this quantity of materials, of upwards of forty-one gallons of spirit, of the strength of one to ten. What is computed here in spirit, may easily be applied to wine, porter, beer, ale, sweets, &c. In barrels allowing three gallons and three quarts of spirit per barrel to the former, and four gallons per barrel to the latter, which gives eleven barrels and three quarters of the one, and ten barrels and a quarter of the other, lost on each brewing of eighty quarters of malt, or the average of that quantity of other materials, by the mismanagement of the fermentation in one point only. It must appear evident to every person capable of investigating this calculation, that every six or seven pounds of carbon, fixed upon each quarter of malt, or other materials, there will be an augmentation of gravity or strength on this number of quarters, of ten or twelve barrels each brewing; that is, every six or seven pounds of this fugitive carbon that we arrest and fix in the fermenting fluid, as a component part of the subsequent produce, by presenting the requisite portion of oxygen and hydrogen, for the purpose within the sphere of each others attraction, we increase our strength in the before-mentioned _ratio_. It is of little moment whether this redundant gas comes from the water of dilution or from the fermentable matter, as under, if we can by any means turn it to account. We have presumed the average quantity of fermentable matter at seventy-five pounds per quarter; this must be evidently on the best goods; this will give us a length of three barrels per quarter of malt of eight bushels, of twenty-five pounds per barrel, specific gravity. Suppose the apparent attenuation of these goods to be nineteen pounds, the transparent gravity will be six pounds per barrel, viz. Gravity of the worts in the cooler just before letting down into the guile-tun, per barrel, 25 lb. Apparent attenuation per barrel, 19 lb. Transparent gravity per barrel, 6 --- 25 lb. Or take it as it really is, viz. specific gravity per barrel, 25 lb. Real attenuation per barrel, 13 lb. 8 oz. Yest and lees, 5 8 -------- 19 lb. Gravity per barrel, when transparent, 6 --- 25 lb. It may be said that nineteen pounds is the real attenuation, and the yest and lees produced is part thereof, as the fluid, or beer, in a state of transparency is but six pounds per barrel specific gravity, and it may, in some degree, be allowed to be so, as there is really so much gravity lost during the process of fermentation. If we multiply thirteen pounds eight ounces, which I have called the real attenuation, by four, we shall find the result to be fifty-four pounds, which is nineteen pounds more of superfluous gas upon four barrels of worts, of twenty-five pounds gravity each, than is extricated from an equivalent quantity of saccharine matter; that is, from one hundred pounds of raw sugar or one hundred and twelve pounds of molasses, and their respective waters of dilution, when the yest and lees do not exceed five pounds eight ounces per barrel. This may be truly called an analysis of the fermentable matter, giving the component parts tolerably exact; though much depends on the management of the fermentation, and the subsequent cleansing. By this analysis it appears, that the mucilage of malt, or grain, gives out more gas than the mucilage of sugar; and leaves a doubt on the mind whether to adjudge the superfluous gas to the fermentable matter, or to the water of dilution, or partly to both; but so it is, that these are the products, whatever source we derive them from, and there is no denying facts. The yest first added is not brought into this account. There is a great similarity of appearance between the two species of low combustion, fermentation and respiration. Fermentation, like respiration, is the spontaneous effort of involuntary motion to decomposition; and in the fermenting mass, as in the animal system, it raises the temperature of both above that of the surrounding atmosphere: that is, it is the cause of heat and involuntary motion, both in the fermenting mass and in the animal system; and, like slow combustion, consumes both, and resolves them into their first principles, from which tendency the latter is constantly withheld by the ingesta, fuel, or food, thrown in. I am well aware I must not carry this reasoning any further. Deep investigation may be thought not to be the object of our research; but we must always have two things in view in inquiries of this nature; indeed, in every pursuit of useful knowledge, where, like the present, it is connected with the first principles, to pursue the winding path of nature, through all her meanderings, up to the ultimate source of these elements, which are the instruments of her operations; and when we are favoured with a knowledge of these, either as the reward of laboured assiduity and attention, or the result of chance, to copy the original as close as we can. I know I shall be justly accused with tautology. I must plead guilty to the charge, not having leisure to apply the pruning hook of correction. The misfortune is, that new doctrines must appear in a new dress, by which they wear the garb of novelty, though, with respect to first principles, there is nothing new under the sun; yet the application of these principles might have remained in oblivion for ever if not called into action. The man who in an age calls them into action, and beneficially applies them for the good of that community of which he is a member, may be virtually, though not literally, called the discoverer of a principle. The man that projects, and the man that executes a voyage of discovery, have superior claims to the man at the mast head who first cries out land. The new turn that the discoveries of modern philosophers has given to natural philosophy, requiring a change of names as well as system; unusual words are unavoidably introduced to express new terms of science, which gives a different character and fashion to the whole, that I should have great pleasure in avoiding, were it possible, which it obviously is not, finding it easier to glide down the stream than oppose its torrent. Notwithstanding that I have calculated upon nineteen pounds only of twenty-five pounds per barrel of fermentable matter being attenuated, and have even in that quantity included five pounds eight ounces of lees and yest, (the least quantity produced,) such calculation must not be admitted to preclude the practicability of attenuating almost every particle of fermentable matter, and replacing it with an equivalent particle of spirit, if that spirit which is now carried off by the avolation of the fixed air, is, agreeably to my proposal, either arrested in its flight, or filtered, after its escape from the guile tun and cleansing vat, by the proper apparatus. Having in a former part of these papers observed, that attenuation may be carried too far, it may be necessary for me to reconcile these seemingly opposite positions, which should be understood in this way: When the quantity of fermentable matter, suspended in a barrel of worts, intended for beer, or ale, is from five to ten pounds more than twenty-five pounds per barrel, every particle of it may be safely attenuated, as the quantity of spirit generated will be sufficient to preserve the beer, or ale, for any requisite length of time, provided it has been properly hopped, &c., or in lieu thereof, received certain other additions to improve its vinosity, strength, and keeping; when the quantity of fermentable matter in worts is from five to fifteen pounds per barrel less than twenty-five pounds, the height of the attenuation ought to be limited on keeping beer and ale; the spirit generated being insufficient to preserve so much fermented fluid in a drinkable state for any length of time, with the usual additions only, even during the summer heats of our own climate; and if so, it is totally unfit for either exportation to warm latitudes, or for keeping at home. For the right understanding of these observations, we should consider that the unattenuated fermentable matter is perpetually furnishing a gradual supply of fixed air and spirit, by means of the imperceptible fermentation always going on in vinous liquors. Weak beers and ales fret and spoil very soon in warm weather, which proceeds from the development and avolation of their fixed air; strong beers and ales have their limits under the same influence of heat, time, change of the atmosphere, &c., and owe their preservation to two things, viz. to a due proportion of fermentable matter unattenuated, or the quantity of spirit they contain; as under these circumstances they are either preserved by the spirit already formed, or that continually supplied by the spontaneous decomposition of the fermentable matter they contain, slowly developing and yielding a fresh supply of air and spirit; hence beer and ales, not too highly attenuated, derive strength and spirituosity from age, when properly stored or cellared, and duly secured from the changes of the atmosphere. These observations are applicable to sweets, or made wines, and to those which are the produce of the grape, the progress of fermentation and attenuation being (or ought to be) interrupted in them by racking off, which is similar to cleansing in beers and ales: and in Madeiras, and other dry wines, the incipient acidity is corrected and restrained, by proper additions introduced in the early part of the process, and with others of similar effect when the wines are making up, either for use or exportation. We may gather from these observations, that worts attenuated for beer or ale, to the decomposition of all their fermentable matter, that is, attenuated so high, or so low, that their specific gravity is reduced to the standard of common water, and from that to the degree of levity spirit is known to give to water, in the proportion to the quantity added, and left to the preservation of the spirit formed, they have little or no auxiliary assistance from their original products, already exhausted by the highest or completest attenuation obtainable; an important circumstance, always to be attended to, particularly by those who affect an unnecessarily high attenuation! The intelligent brewer may, by the assistance of these observations, form a most accurate rule for the regulation of his future conduct in the management of fermentation, according as his beer or ale is to be weak or strong, or for present use or long keeping; for the accomplishment of which, the use of the hydrometer and thermometer claim his peculiar attention, and will undoubtedly answer his expectations, when joined to the certainty he is now at, of knowing when he is, or is not, to expect the development of fixed air and additional spirit, by which he can govern himself accordingly. These observations lead to a removal of the difficulties that lay in the way, and, at the same time, suggest a mode of applying the present, or of constructing a future _hydrometer_, for ascertaining the strength or the quantity of the vinous spirit in beer, wine, ale, and other fermented fluids, which has long been a desirable object. The distiller, having none of these niceties to attend to, is governed by the ultimate extent of the attenuation the worts, or wash, is found capable of, and which is both assisted and protracted by its superior density, in its progress from specific gravity to specific levity, if such an expression is admissible. Fermentation, begun in a fluid more or less saturated with saccharine or fermentable matter, the process is finished sooner or later, and usually in proportion to the degree of saturation, and the being conducted with more or less vigour under a well regulated temperature; for the more a fluid abounds with this matter, the grosser and denser it must necessarily be, and the longer will the attenuation be protracted; the longer it is protracted, in air-tight vessels, and in a healthy and vigourous state of decomposition, the more spiritous and strong will that wash turn out, and the greater the produce of spirit in distillation; hence, it is both protracted and assisted by its density. A languid may be truly called an unhealthy decomposition, it being productive of diseases common to misconducted fermentation, acidity, putridity, and lack of spirits, with a tendency to precipitate and burn upon the bottom of the still; hence, all the decompositions are confounded together, as in spontaneous fermentation. The formation of acidity during the process, is not of that injury to the distiller that it is to the brewer, nor is this recent acidity vinegar, as has been supposed by some chemists, but the incipient state of combination of resolving elements, whose particles are in that juxtaposition best suited to absorb developing hydrogen in a nascent state, and intimately to combine with it into vinous spirit, the approximation to which is promoted by time and incumbent pressure: these positions shall be explained as I proceed. The reason that putridity is so rarely discovered in excited fermentation, is, that it is usually counteracted by the previously evolved acidity, and corrected, but not saturated or neutralized; for, were that the case, the putrid could not immediately succeed the acetous process in the same fluid, nor exist together, as they are known to do in declining beer, vinegar, &c. The reason that acidity is not more frequently observed and attended to than it is, is because of its being sheathed or covered by the unattenuated sweets, or fermentable matter of the wash that remains undecomposed. On the other hand, when acidity is very prevalent, it may be mistaken for unattenuated fermentable matter, acidity increasing the density and specific gravity of the fluid. Putridity, from the avolation of its products, promotes levity, and that in proportion as its increase surpasses that of the general acid; and it is not until the action of the acetous becomes languid, that the putrid process gains the ascendency, when it is then difficult to overcome. Although these observations may show how the hydrometer, or its use, in unexperienced hands may be baffled, they both distinguish and explain the value of its application; they do more--they elucidate the doctrine of fermentation, and illustrate the goodness of Providence, who has made nothing in vain, but provided nature with its own resources for conducting every operation in the great plan of the universe with uniform and unerring security. In the decomposition of fermentable matter, either by combustion or fermentation, (which I have defined to be synonimous,) a portion of inflammable air, or hydrogen, is first evolved; secondly, another portion of inflammable air, united with pure air, or oxygen gas, evolves under the form of fixed air; this is the constant and uniform phenomena of these decompositions, and are progressively going on from the beginning to the end of the fermentation, while there is any fermentable matter to attenuate. A due portion of oxygen uniting in a nascent state with a correspondent portion of inflammable or hydrogen, and fixed air, forms the spiritous particles dispersed through the fermenting fluid, which create vinosity, and constitute it wine, beer, or wash. During which, so great is the avolation of fixed air, (as we have seen,) that much of the ethereal part of the new formed, or, rather, the scarcely-formed spirit, is carried off with it in a gaseous state. This is much assisted by the agency of the atmosphere, which is the solvent and receptacle of ethereal products, whose affinity for them must be as great as it is perfect and immediate--which demonstrates the necessity of having air-tight vats. When we consider the composition of the atmosphere, and that it owes its formation and existence to this cause, and, thereby becomes the menstruum of all created matter, we may be better able to understand the composition and formation of vinous spirits, and, by closely copying the original, more successfully imitate nature. We have seen that the principal phenomena in fermenting fluids is a brisk intestine motion of their parts, excited in all directions with a loss of transparency, or a muddiness, a hissing noise, the generating of gentle heat, and an exhalation of gas. This heat, we must now observe, is always very sensible before the extrication of any gas. We have adverted to the similarity existing between respiration and fermentation, which is remarkably so in the equality of heat produced in both in a healthy state of either, and which seldom exceeds ninety-six degrees of Fahrenheit's thermometer; but there are instances of their being much higher in both, without producing much injury to either. Instances of this could be adduced at home, without referring to warmer climates of the East and West Indies, where the temperature of the atmosphere is so much higher than with us; and that the temperature of the fermenting fluid, when at its height, always exceeds that of the surrounding atmosphere in these latitudes, which makes the similarity still stronger between these two decomposing processes. This is a general and just remark; but, in order to regulate it by practical facts, we must name the medium standard of heat, which rarely exceeds eighty-five degrees with the brewers; this is the medium of seventy-four and ninety-six degrees; but the medium heat is not unfrequently up to ninety-six degrees in the distiller's fermenting backs of Great Britain. Much depends on the degree of temperature the fermentation is pitched at: here, nothing is spoken of but the cleansing heat with the brewers, and the medium heat with the distillers. For the maintenance of combustion, the free access of air being necessary, an objection may be raised to air-tight vats, as unfit to carry on this process in, to the exclusion of external air; which objection may seem to gather force from the compression it occasions of the fixed air on the decomposing fluid, which is allowed to extinguish active combustion. I must acknowledge these are formidable objections to my definition of low combustion, but I by no means find them unanswerable. The aptitude of new hay, malt, and other vegetable matters, to spontaneous combustion, when impacted together by incumbent pressure, and a certain degree of moisture, should be recollected; and that this tendency is not destroyed by excluding the admission of external air, but by quickly cooling and dividing the impacted hay. The great quantity of oxygen, or vital air, both in the water of dilution, and in the fermentable matter, with which the fluid is more or less saturated, should be also recollected, which is about eighty-five parts in the former, and sixty-four parts of one hundred in the latter. Though, in an unelastic or fixed state, it is one of the properties of combustion to disengage and render it elastic, great part of which, during the low combustion which it supports, and in which heat is visible or perceptible, and light in an invisible state developed, three parts of this oxygen, with about one third of its weight of carbon, is converted into an elastic state, under the form of fixed air, that separates from the decomposing mass; a circumstance attending also on the combustion of coal and other combustible substances during their decomposition by that process, which supported in them by the external air of the atmosphere, where heat and light are both visible from the intensity and velocity of the combustion; and wholly invisible in the former, not from exclusion of external air, but from the length of time elapsed in low combustion; the one being performed instantaneously, and the other taking several days from its decomposition. Although fixed air is known to extinguish a lighted candle, and destroy animal life, that is, to be equally unfit for the combustion of inflammable bodies, or the support of animal respiration, it is also known to be as successfully employed as atmospheric air, or even dephlogisticated air, to melt glass, &c., when applied to the clear flame of a wax candle, by passing a current of it through a blow-pipe, to direct that flame on the glass to be melted.[4] [4] Count Rumford on the Economy of Fuel. This will not be so much to be wondered at, when we consider that the proportion of vital air in fixed air is as twenty-seven to nine, and in atmospheric air, the proportion of azotic gas or phlogisticated air, to vital air, is as seventy-three to twenty-seven; therefore, the former contains three fourths of vital air, and the latter little better than one fourth; but the fixed air is in a combined, and the phlogisticated air in an uncombined state. Among the processes made use of by nature for the decomposition of vegetable and animal substances, fermentation, or low combustion, is a principle one. Air, in a fixed or unelastic state, may be as necessary here as air in an elastic state is known to be in the active combustion of inflammable bodies. Chemists and philosophers are no strangers to two sorts of combustion, one in external air, and the other in close vessels. But this is not the combustion alluded to in fermentation, where all the requisites for complete decomposition is to be found independent of contact with the atmosphere; here one part is oxygenated at the expense of the other, and the other disoxygenated in favour of it. Nor does the solution, or decomposition of metals by acids, the combustion of inflammable and vital air for the production of water, stand in need of external heat or fire, any more than the low combustion in which fermentation consists for the production of spirit, beer, or wine, than that generated by the self-operation of its own temperature; similar to this is the self-animating principle or power with which nature has endowed the animal body of generating its own heat by respiration. In fermentation, the caloric, or matter of heat, which is plentifully disengaged by the condensation of oxygen, is prevented from breaking out into flame with the condensing hydrogen, from the presence of affinities in the fermenting mass, ready to absorb and fix them into vinous spirit, ale, beer, &c., with the other component element, carbon; by which they are too instantaneously taken up and fixed, to amount to more than bare ebullition, and pass at once from an incipient state of elasticity, to a fixed and non-elastic one, while the redundant heat, which would otherwise appear, is taken up and carried off by the abundant formation of carbonic acid gas, which requires so great a quantity of caloric to render it permanently elastic, as not only keeps this sort of combustion under ignition, but much below the degree of heat at which the accumulating vinous spirit could be raised to the evaporable or distilling point, though capable, as already observed, of detaching a considerable portion of it with the volatile gas, and of the water of solution, or the water of composition recently formed from the present attractions in its most volatile and incipient state of formation; both which we have seen ascend with the fixed air extricated, partly in a combined, and partly in an uncombined state. One part of hydrogen is sufficient to saturate and fix above five of carbon, and they require nearly sixteen parts of oxygen to complete their formation into alcohol, while the water of dilution undergoes a proportionate decomposition and recomposition, to assist the resolutions and combinations, and support the admirable equilibrium preserved by nature. At the same time that the extreme levity of the hydrogen gas accounts for the great quantity of heat which it holds in combination, and the high temperature requisite to effect its decomposition, and that such is its capacity for heat, that though combined with oxygen and water, it still possesses the property of absorbing a great deal more. It is this property that renders aqueous vapour lighter than atmospheric air in which it ascends; yet we have just now demonstrated the resolution and combination of hydrogen gas, and oxygen gas, both extricated from the fermentable matter and the water of dilution, and their formation into spirit, &c., at a temperature not many degrees above that of the incumbent atmosphere, and no higher than that excited by respiration in the animal system. In which we have shown the vegetable oxyde, (saccharine matter,) when reduced by the admixture of water, to form the worts or wash, to be a carbonated hydrogenous fluid, containing the elements of wine, beer, ale, spirit, &c., and the mode of producing them under circumstances conducive to their formation; these are motion, heat, pressure, and mutual attraction, called into existence by a species of low combustion, or fermentation, somewhat similar to respiration. In which the materials, the products, and the liberation of caloric are ultimately the same, whether the operation is attended by visible fire from the velocity of action, or weak incalescence from the slow progression of its motion; in which the component elements are continually assuming a gasseous form, and as constantly losing it by the force of mutual attraction for each other. No sooner is the equilibrium broken, in one instance, by their gasseous appearance, than it is restored by their condensation, and the heat liberated by the latter taken up by the former, by which the equilibrium is preserved; in this consists the increase of temperature above that of the surrounding atmosphere, accompanied by the discharge of fixed air; to fix, and advantageously apply which, shall be the next consideration; and, by an accurate imitation of the modification employed by nature, to render the fermenting fluid so much the stronger by such fixation. To accomplish which, we must advert to what has been delivered in the preceding pages, particularly to the proportions in which the equilibrium preserved by nature consists, and exactly to her manner of combining them in sugar, malt, and other saccharine matter, her mode of breaking this equilibrium, or decomposing them by fermentation, and recombining them into wine, beer, &c., and by the same process restoring the equilibrium. It cannot be doubted, but that, in the investigation of the acetous process of fermentation with the attenuation we do the vinous, they will mutually reflect light on each other; in which it will come out that wine, beer, ale, vinegar, spirit, &c., are not the only commercial preparation to which the doctrine of fermentation, or low combustion, may be advantageously applied, but also to others, that are perhaps equally important and productive. The cleansing being at the meridian, or greatest temperature of the heat of the fermenting fluid, and the object of that cleansing being to reduce the heat, and thereby allay the violence of the fermentation, by which an immediate decomposition takes place, the lighter impurities buoyed up to the top of the fluid flows off with the yest, while the heavier dregs descend to the bottom, and the fermentation gradually declines as the cleansing draws to a conclusion, and the fermenting fluid forms a turbid heterogeneous mass, very perceptibly approaching towards a transparent homogeneous fluid in its progress to a drinkable state. In laying out a brewery, the air should have free access to the coolers on all sides, under and over; cleansing vessels should be similarly situated, and, if avoidable, the coolers should not lay immediately over them, to raise their temperature, which should not be many degrees above that of the atmosphere, at temperate, which is fifty-two degrees; but the descent from the cleansing heat (seventy-five to eighty-five) should be progressive, that is, not sudden. A sudden chill would precipitate the grosser, and diffuse the lighter dregs throughout the fermenting fluid, which should be thrown off from the surface in cleansing; this would retard the fining, and empoverish the beer or ale; while the mode recommended will be found to promote transparency, and give strength and body, that is, fullness and spirituosity. In general, the cleansing commences too soon for the strength and quality of the goods, particularly for porter, since the introduction of a greater proportion of pale malt than formerly used; a more perfect fermentation is now requisite to keep up the genuine distinction in that flavour of porter from ordinary beers and ales, which, since the change of _lengths_, has much declined, though the only characteristic quality that gives it merit over other malt liquors--an object that deserves consideration in this great commercial branch of trade, and source of national wealth, where the loss of distinction will be the loss of trade. The rough, astringent, thirst-creating smack is the produce of the brown malt, and a well conducted fermentation. The porter now brewed can no more bear the sudden chill of a cooling atmosphere in the barrel cleansing, without too immediate a condensation and separation of its parts, than it is able to sustain the quick changes of a warm atmosphere, without an immediate tendency to acidity. As things now are, either extreme can only be avoided by a more attentive advertence to the mode of _cleansing_, so as to prevent a predominant tendency to either by adopting the means proposed, or such other, on the same principles, as are equally likely to preserve the quality, increase the strength, promote transparency, and avoid acidity. I know it may be urged by the most able brewers, that a high and rapid fermentation in the cleansing is a principal cause of that flavour for which porter is distinguished; that this kind of fermentation leads to a more perfect attenuation; and some of them may, with great truth, add, a perfect attenuation is the genuine mode of early bringing beer forward. This I most readily grant; it is the doctrine I wish to inculcate. The greater gravity of keeping beers, preserves them in a _mild state_, while their spirituosity prevents acidity. The flavour of the colouring matter now in use, nor the change it induces, is not, by any means, adapted to preserve the genuine flavour of porter, or compensate for that made in the change of malt; a change I by no means condemn, with respect to the malt; but however advantageous to the length, we must not altogether give up flavour, while we may equally as well, and indeed much better, preserve both by a due admixture of each sort of malt, and with suitable additions and proper correctives in the process or preparation of porter, both salubrious; as by the subsequent mixture of stale and mild beer, before sending out, or, afterwards, by drawing them from different casks into the same pot, when on draught, to suit the palate of each respective customer. I hope it is by this time understood, that my views are to raise the _Process of Brewing_ above the vulgar error that tyrant custom has entailed on it, and by the free exercise of the brewer's abilities, both in a scientific and tradesman-like manner, so as advantageously to preserve flavour and quality, with almost any proportions of every sort of malt he may occasionally be obliged to use. The world is continually exclaiming that _experience_ is better than _theory_. This is very true; for example, he who has had a very long experience, may, in general, perform operations with tolerable exactness; but this he undeviatingly does by certain stated means, without any deeper intelligence of the process. I would, with Mr. _Chaptal_, compare such a man to a blind person who is acquainted with the road, and can pass along it with ease, and perhaps even with the confidence and assurance of a man who sees perfectly well, but is at the same time incapable of avoiding accidental obstacles, of shortening his way, or taking the most direct course, and alike incapable of laying down any rules which he can communicate to others. This is the state of the artist of mere experience, however long the duration of his practice may have been, as the simple performer of operations. Brewing, fermenting, distilling, &c., are branches of commercial chemistry, that generally challenge the attention and secure the protection of those governments that constitute them sources of revenue and trade. Chemistry is as much the basis of the arts and manufactures, as mathematics is the fundamental principle of mechanics. In the process of brewing porter, ale, threepenny, &c., to be subsequently treated of, the practical minutia of fermentation and attenuation shall be circumstantially laid down in each, so as to account for, and distinguish the variety of flavour, &c., assignable to each _cause effected_ by the different modes of treatment. _Hops, the best method of cultivating and raising them._ A rich, deep soil, rather inclining to moisture, is, on the whole, the best adapted for the cultivation of hops; but it is observable that any soil (stiff clay only excepted) will suit the growing of hops when properly prepared; and in many parts of Great Britain they use the bog-land, which is fit for little else. The ground on which hops are to be planted should be made rich with that kind of manure best suited to the soil, and rendered fine and mellow by being ploughed deep, and harrowed several times. The hills should be at the distance of six or eight feet apart from each other, according to the richness of the ground. On lands that are rich, the vines will run the most; the hills must therefore be the further apart. At the first opening of the spring, when the frosts are over, and vegetation begins, sets, or small pieces of the roots of hops, must be obtained from hops that are esteemed the best.[5] Cut off from the main stalk or root, six inches in length, branches or suckers, most healthy, and of the last year's growth, if possible to be procured; if not, they should be wrapped in a cloth, kept in a moist place, excluded from the air. A hole should then be made large and deep, and filled with rich mellow earth. The sprouts should be set in this earth with the bud upwards, and the ground pressed close about them. If the buds have begun to open, the uppermost must be left just out of the ground, otherwise cover it with the earth an inch. Two or three sets to a pole is sufficient, and three poles to a hill will be found most productive; place one of the poles towards the north, the other two at equal distances, about two feet apart. The sets are to be placed in the same manner as the poles, that they may the easier climb. The length of the poles may be from fourteen to eighteen feet, according as the soil is rich or poor. The poles should be placed so as to incline to each other, meet at their tops, and there be tied. This is contrary to the European method, but will be found best in America. In this way they will strengthen and support each other, and form so great a defence against the violent gusts of wind, to which our climate is frequently subject in the months of July and August, as to prevent their being blown down. They will, likewise, form a three-sided pyramid, which will have the greatest possible advantage from the sun. It is suggested by experience, that hops which grow near the ground are the best. Too long poles, therefore, are not good, and care should be taken that the vines do not run beyond the poles, twisting off their tops will prevent it. The best kinds of wood for poles are alder, ash, birch, elm, chestnut, and cedar, their durability is directly the reverse of the order in which they stand; charring, or burning the end put into the ground, will preserve them. Hops should not be poled till the spring of the second year, and then not till they have been dressed. All that is necessary for the first year, is to keep the hops free from weeds, and the ground light and mellow by hoeing and ploughing often, if the yard be large enough to admit of it. The vines, when run to the length of four or five feet, should be twisted together, to prevent their bearing the first year, for that would injure them. In the months of March or April, of the second year, the hills must be opened, and all the sprouts or suckers cut off, within one inch of the old root, but that must be left entire with the roots that run down;[6] then cover the hills with fine earth and manure. The hops must be kept free from weeds and the ground mellow by hoeing often through the season, and hills of earth gradually raised around the vines during the summer. The vines must be assisted in running on the poles with woolen yarn, suffering them to run with the sun. By the last of August, or the first of September, the hops will be ripe, and fit to gather. This may be easily known by their colour changing, and having a fragrant smell; their seed grows brown and hard. As soon as ripe, they must be gathered without delay, for a storm or frost will injure them materially. The most expeditious method of picking hops, is to cut the vines three feet from the ground, pull up the poles and lay them on crotches, horizontally, at a height that may be conveniently reached, put under them a bin of equal length, and four may stand on each side to pick at the same time. Fair weather should always be chosen to gather hops and they should never be gathered when dew or moisture is on them, as it subjects them to mould. They should be dried as soon as possible after they are gathered; if not immediately, they must be spread on a floor to prevent their changing colour. The best mode of drying them is with a fire of charcoal and kiln, covered with hair cloth in the manner of a malt-kiln.[7] The fire should be steady and equal, and the hops gently stirred from time to time. Great attention is necessary in this part of the business, that the hops be uniformly and sufficiently dried; if too much dried they will look brown, and, of course, be materially injured in their quality, and proportionably reduced in their price. If too little dried, they will lose their natural colour and flavour. They should be on the hair cloth about six inches thick after it had been moderately warmed, then a steady fire kept up till the hops are nearly dry, lest the moisture or sweat the fire has raised should fall back and change their colour. After the hops have been in this situation seven, eight, or nine hours, and have got through sweating, and when struck with a stick will leap up; then throw them into a heap, mix them well, and spread them again, and let them remain till they are all equally dry. While they are in a sweat, it will be best not to move them for fear of burning, slacken the fire, when the hops are to be turned, and increase it afterwards. Hops are sufficiently dried, when their inner stalks break short, and their leaves become crisp, and fall off easily. They will crackle a little when their seed is bursting, and then they should be removed from the kiln. Hops that are dried in the sun lose their rich flavour, and, if under cover, they are apt to ferment and change with the weather, and lose their strength; moderate fire preserves the colour and flavour of the hops, by evaporating the water, and retaining the oil of the hop. After the hops are taken from the kiln, they should be laid in a heap, to acquire a little moisture to fit them for bagging. It would be well to exclude them from air by covering them with blankets. Three or four days will be sufficient for them to be in that state. When the hops are so moist that they may be pressed together without breaking, they are fit for bagging. Bags made of coarse linen cloth, eleven feet in length, and seven in circumference, which hold about two hundred pounds weight, are most commonly used in Europe: but any size that best suits may be made use of. To bag hops, a hole is made through the floor of a loft, large enough for a man to pass through with ease. The bag must be fastened to a hoop, larger than the hole, that the floor may serve to support the bag; for the convenience of handling the bags, some hops should be tied up in each corner of the bag, to serve as handles. The hops should be gradually thrown into the bag, and trod down continually, till the bag is filled. The mouth of the bag must then be sown up, and the hops are then fit for market. The closer and harder hops are packed, the longer and better they will keep; but they should be kept dry. In most parts of Great Britain where hops are cultivated, they estimate the charge of cultivating one acre of hops at forty-two dollars, for manuring and tilling, exclusive of poles and rent of land; poles they estimate at sixteen dollars per annum, but in this country they would not amount to half that sum; one acre is computed to require three thousand poles, which will last from eight to twelve years, according to the quality of the wood used. The English growers of hops think they have a very indifferent crop if the produce of one acre does not amount to one hundred and thirty-three dollars, but, much more frequently, it amounts to two hundred dollars, and sometimes so high as four hundred dollars per acre. In this country, experiments have been equally flattering. A gentleman in Massachusetts, in the summer of 1791, raised hops, from one acre of ground that sold for three hundred dollars; it is allowed, that land in this state is equally favourable to the growth of hops. Upon a low estimate, we may fairly compute the nett profit of one acre of hops to be eighty dollars, over and above poles, manure, and labour; and in a good year a great deal more might be expected. There is one circumstance further we think has weight, and ought to be mentioned: in the English estimate the expense put down is what they can hire the labour done for by those who make it their business to perform the different parts of the cultivation. A great saving may, therefore, be made by our farmers in the article of labour, for much of it may be performed by women and children. Added to this, we have another advantage of no small moment in this country: the hop harvest will come between our two great harvests, the small grain and Indian corn, without interfering with either but in England the case is otherwise: the small grain and hop harvest come in together, and create a great scarcity of hands, it being then the most busy season of the year. It is found, by experience, that the soil and climate of the eastern states are more favourable to the growth of hops than Great Britain; they not being so subject to moist, foggy weather of long continuance, which is most injurious to hops; and the southern and middle states are still more favourable to the growth of hops than the eastern states, in point of flavour and strength. The State of New-York unites some advantages from either extreme of the union. The cultivators of land in this state have every inducement, which policy or interest can offer, to enter with spirit into the cultivation of hops; as we shall thereby be able to supply our own demand, which is now every year increasing, instead of sending to our neighbours for every bag we consume; a circumstance the more unaccountable, as hops, are on all hands, allowed to be one of the most profitable crops that can be raised; the culture requires but little land, the labour may be performed at intervals, so as not to interfere with other business of the farm, and be generally performed by women and children. There is hardly a farmer in this state but may, with ease, raise from one quarter of an acre, to as much as three or four acres, the advantage of which would, in a few years, be most sensibly felt both by the individual concerned, and the state at large. In the city of New-York there are, at present, a number of large and respectable breweries, and new ones, from time to time, may reasonably be expected to be added to their number. All these establishments are now supplied with hops from Massachusetts and Connecticut; these considerations should certainly stimulate a few spirited cultivators to lead the way, and raise hops; their laudable example would soon be followed by others; so that in a few years we should have prime hops of our own in abundance, for home consumption or exportation. This subject will, I hope, appear sufficiently important to recommend itself; to say more is therefore unnecessary. [5] Of the different kinds of hops, the long white is the most esteemed; it yields the greatest quantity, and is the most beautiful. The beauty of hops consists of their being of a pale bright green color. Care should be taken to obtain all of one sort; but if different sorts are used, they must be kept separate in the field, for there is a material difference in their time of ripening; and if mixed in the field, will occasion extra trouble at the time of gathering them in. [6] Hops must be dressed every year, as soon as the frost will permit; on this being well done depends, in a great measure, the success of the crop. It is thought by many to be the best method to manure the hop yard in the fall, and cover the hills entirely with the manure, asserting, with other advantages, that this prevents the frost from injuring plants during the winter. Hops had better be gathered before they are full ripe than remain till they are over ripe, for then they will lose their seed by the wind, or on being handled. The seed is the strongest part of the hop, and when they get too ripe will lose their green colour, which is very necessary to preserve as the most valuable part of the [remainder of text is illegible] [7] Kilns covered with the splinters of walnut, or ash, will answer the purpose, and come cheaper than hair cloth. _Barley Cultivation._ However unconnected this subject may appear with a treatise on brewing, I cannot help thinking that, in this country, it is much more intimately connected with it than one would, at a first view, incline to suppose, and for the following reasons; first, Because the proper cultivation of barley is not generally known, save in the eastern states, and but very little raised in any of the others; secondly, Without good barley it is impossible to make good malt, consequently, good beer--and it must be acknowledged, that a great proportion of the barley that is raised, even in the eastern states, is but very imperfectly suited to the purposes of the brewery, being what is termed winter barley, and generally a poor, thin, lank grain, by no means qualified to make good malt. This is so well known in England, that it is very rarely met with in the barley markets, and seldom, or ever, purchased by a brewer. The summer, or spring barley, always getting the preference, being the largest bodied grain, and, of course, the best suited to the purposes of making prime malt, the want of which, is frequently severely felt by the brewers of this country, from the impossibility they often find themselves in of procuring good barley, being obliged to use such as they can get, which, for the most part, is very ill suited to their purpose. It will be, then, their interest to give every encouragement to the farmer to raise spring barley in preference to the winter, to procure the best seed, of that description, that he can find, to clean it well, to steep it in well or spring water for twelve hours, stirring it frequently from the bottom of the tub or vessel all around; and previous to each stirring, all the floating grains, seed weeds, &c., should be carefully skimmed off: thus nothing will remain for seed but sound and perfect grain. The first water should be drawn off at the end of six hours, and immediately replaced by fresh; this again drawn off at the end of six hours more; it should be sown, broad cast, the following day, being first previously mixed with a sufficient quantity of wood ashes to dry it as much as will be necessary for the purpose of sowing. Thus managed, if the ground be in proper tilth, and fitly prepared, this grain will make its appearance the fifth or sixth day after sowing; whereas, if the seed be sown dry, it will probably be three weeks or more before it comes up, particularly if the season be dry. I cannot more forcibly recommend this practice than by giving a brief sketch of an experiment made in England, and taken from the Bath and West of England Society's reports. A farmer selected four acres of the same field, treated and prepared it for seeding exactly in the same way, he then divided it into two equal parts; he sowed one part with dry seed, in the common way, the other with steeped seed, as here recommended, and the consequence was, that the latter produced a double crop, although the seed in both cases was the same, save the difference of treatment. The superior quality and condition of the crop seemed to keep pace with the increased quantity. The beginning or middle of March, if the weather be dry, is the best time to sow spring or summer barley. This mode of preparing seed wheat, is highly recommended as an assured preservative against the smut, fly, &c., insuring a sound good crop of grain. Barley should be always cut in dry weather, yet not suffered to be too ripe before cutting; stacking it in the field for a few weeks before removing it to the barn, helps and prepares it for malting, by sweating and drying it. Barley, immediately brought to the malt house from the field, rarely makes good malt, as a great proportion of it becomes staggy, and will not grow. Those who can corroborate the truth of these remarks, and sufficiently appreciate them, will readily justify and excuse this seeming departure from the original plan of this little work. _Table Beer._ There is no production of the brewery more important to society than good table beer, whether it be considered as a diluent to animal food, or a diet drink in fever cases, even of the most malignant kind, where, to my knowledge, it has been preferred to all others, and that with the greatest success, sanctioned by the advice of some of the most eminent physicians. This justifies my recommending it, and giving several processes for making this useful liquor. _Small Beer for Shipping._ 12 Bushels of Pale Malt. 12 Bushels of Amber Malt. -- 24 -- 14 lb. of Hops. Cleansed 24 Barrels. Let your malt be fine ground; first liquor 172; mash one hour, stand one hour, run down smartly; beat of second mash 180; mash one hour, stand two hours, boil two hours; making your length sufficiently long to give one barrel of beer to each bushel of malt. Pitch your tun at 70 degrees, giving one gallon of solid yest; cleanse within twenty-four hours. The fresher this beer is sent out the better: being very thin in body and low priced, it cannot be expected to last long. _Keeping Table Beer._ PROCESS. Commenced brewing at six in the morning, heat of the air 60 degrees, per Fahrenheit's Thermometer. 48 Bushels of Pale Malt. 16 Bushels of Amber Malt. -- 64 -- 72 lb. of Hops. Cleansed 45 Barrels of Table Beer. 10 lb. liquorice ball, which was previously melted down in boiling water, by frequent stirring, to a liquid, and then put in with the hops when added to the worts. Ran the necessary quantity of boiling water into the mash tun for the first mash, and when cooled down to 168, commenced mashing, which continued three quarters of an hour, stood one hour, ran down briskly; mashed a second time at 180, for half an hour; stood half an hour; mixed both worts, boiled one hour and a half as hard as possible, throwing into the copper, before boiling, half a pound of ground ginger, with half a pound of ground mustard; pitched these worts at 70 degrees, giving 3 gallons of solid yest; remained in the tun 36 hours, and was headed over, before cleansing, with four pounds of flour and one pound of salt mixed together. This kind of beer will have attenuated sufficiently in from 30 to 36 hours. _Small Beer of the best kind, how brewed, which, in a good cellar, will keep as long as can be reasonably wanted._ MATERIALS. 15 bushels of Pale Malt. 7 lb. Hops. Cleansed 10 1/2 Barrels Beer, heat of the air 50 by Fahrenheit's Thermometer. Boiled the first copper; drew the fire; then ran ten inches of boiling hot water into the keeve; added two inches of cold water, mixed both well together, which made up at 168; then put in the malt gradually, mashing all the time, for about half an hour; the mash being thin, did not require a longer operation. Before mashing, rubbed the 7 pounds of hops in a tub, sprinkling over them, when rubbed, about one quarter of a pound of white salt, then poured on boiling water in sufficient quantity to saturate them well, after which they were close covered; the keeve having stood two hours, the tap was set, and ran down twelve inches. Did not boil the second copper, but raised its heat to 184, mashed a second time, and stood one hour, ran down as before, and completed the length in the underbank, cleared the copper, had it rinced out, got up the worts, put in the hops, extract and all, made up the fire, and boiled one hour and a half as hard as possible, previously adding to them four pounds of brown sugar that had been dissolved in a bucket with hot water, also half a pound of ground mustard; this beer remained on the coolers about eight hours, pitched it next morning at 72 degrees, adding only one gallon of solid yest, ran slowly into the tun which made up at 61 degrees; came on gradually, remained in the tun 31 hours, and raised to 66, affording but two degrees of attenuation. Notwithstanding this beer worked well in the casks, yet moderately, was frequently filled at close intervals, and was glass fine the fifth day. The sugar was added to assist the colour as well as the strength, the mustard to give flavour. _Another Method._ To brew small beer somewhat stronger, take 30 bushels of pale malt, (have it ground fine,) 10 pound of hops, steep them as in the preceding process. Turn out of your copper 16 barrels of beer, give your first liquor at 165, your second at 175, mash, run down, stand, and boil as before. But before you commence brewing, take five pounds of brown sugar, put it into a metal pot with some water, set it on the fire, keep it constantly stirring till it begins to smell strong, then take it off the fire, and add to it, gradually, three gallons of water, at the temperature of blood heat, stirring the water and the sugar well together, till the whole be perfectly blended; this prepared liquor should be added to the worts in the copper before boiling. The fermentation, &c., to be conducted as before, save only the pitching, yest, to be increased by half a gallon, which half gallon is not to be added to the worts until twelve hours after the first gallon. Attenuation should proceed until the heat rises four degrees above the pitching heat, which should be the same as in the preceding process. In both instances, the tuns should be covered during the period of fermentation, but taken off for the purpose of rousing before cleansing; these covers should be put on again, in order to prevent the dispersion or waste of the gasses, which is always a loss of spirituosity. _A good sound keeping Table Beer may be Brewed from wheaten Bran and Shorts, and, in many situations, when Malt cannot be procured, would be found an excellent substitute. This process is well worth the attention of housekeepers._ PROCESS AS FOLLOWS: 40 Bushels of Shorts. 20 Bushels of Bran. 16 lb. of Hops will give 25 Barrels of Small Beer. Boil your first copper, run into your mash tun as much boiling water as, when reduced with cold, will bring it to the temperature of 1.0, then commence your mashing operation, putting in two bushels of shorts, and one bushel of bran at a time; when these are well mixed with the water, put in more, mash again, and so continue to do till all is in; it will take from half an hour to three quarters to mash this quantity properly; let your mash stand two hours, run down as in the preceding processes, and give your second liquor 165; mash a second time, stand one hour, boil your first wort one hour very hard with half your hops, which should have been steeped, rubbed, and salted, as before directed; boil your second wort one hour and a half in the same way, putting on the remainder of your hops, with one pound of ground mustard, and five pounds of brown sugar, reduced, by boiling, to a colouring matter, as already directed in the previous process; make up your two boilings in your tun at the heat of 65, giving three gallons of solid yest; let your attenuation proceed ten degrees, or to 75, then cleanse, and continue to fill your casks in the usual way. It has been found that beer brewed from these materials has stood the summer heats much better than beer brewed from malt alone; this may be accounted for by the extract of malt possessing a much larger proportion of saccharine matter than that obtainable from bran and shorts. In families, this beer may be brewed in the proportion of one or two barrels at a time; and in the country, where brewer's yest may not be procurable, leaven, diluted with blood-warm water, may be substituted for brewer's yest, and will answer, but not so well; neither will attenuation go so high, as fermentation with leaven, when applied to liquids, is generally languid and slow. _Single Ale and Table Beer._ 100 Bushels of Malt. 60 lb. of Hops. Heat of the air 50 degrees. Cleansed or tunned 30 Barrels of Single Ale; with 16 Barrels of Table Beer after. First, or mashing liquor, 168, run your whole quantity of boiling liquor into your mash tun, and when it cools down to the above point of 168, begin to run in your malt gradually from your malt bin; this quantity will require four or five hands to mash it well, which will generally take three quarters of an hour; when sufficiently mashed, cover your tun, let it stand two hours; run down this first mash smartly by two cocks within the hour; let your hops be rubbed, steeped, and salted, as before directed; added to these worts, as they began to boil, three gallons of the essentia bina or liquid colouring, with one pound and a half of ground mustard, and one pound of liquorice root finely powdered, boiled the whole two hours as hard as possible, there being a second copper for this operation, there was liquor prepared for the small beer and run on the keeve at the heat of 185; mashed well a second time, and stood two hours; by this time the first wort was let run into the hop back, and so on the cooler. After which, ran down the small beer, got it into the small copper, adding about six hand buckets of the hops that had been boiled on the single ale; these answered to preserve the beer, with one pound of ground mustard to assist flavour, and two gallons of the essentia bina to give colour; boiled the small beer one hour smartly. The strong worts were let into the tun in three portions, there being three coolers; the first division, at 65, had two gallons and a half of yest given to it; the second, at 66, the same quantity of yest; the third, at 65, was let down without yest, when all were in the tun made up at 64; in thirteen hours the tun had a handsome appearance of work; came on regularly, and attenuated to 76, having gained 12 degrees within sixty hours, then cleansed and filled the casks every three hours for the first eight fillings. Thus managed, this single ale was fit to send out the fifth day after brewing. When this ale is racking off the butts, to be sent out, would recommend putting two ounces of ground rice into each barrel which will create briskness, and much improve the beer. Ran the small beer into the hop back of the strong beer, and so on the coolers, thereby giving it a chance to lick up all the strong ale it met with in its progress to the tun, which it entered at 65 with three gallons of yest, and was cleansed within thirty-six hours. The quantity of beer here mentioned would be much improved by the addition of six or seven pounds of brown sugar or molasses; but if good table beer is wanted, it can be only obtained from whole grists of malt, and is well worth the difference of expense to those who can afford it, and appreciate quality. _Strong Beer._ Brewed, November, 1810, the following materials. Heat of the air 50 degrees. 40 Bushels of Pale Malt. 20 Bushels of Amber Malt. -- 60 -- 40 lb. of Hops, the best quality. Cleansed 20 Barrels of Beer. Rubbed, salted, and steeped the hops, as already directed, in a close vessel, ran a sufficient quantity of boiling water on the mash tun for the first mash, which was suffered to cool down to 165; mashed well for nearly one hour, stood two hours; ran down smartly, boiled the first wort one hour very hard, with about half the hops; mashed a second time at about 185: took about half an hour in the operation, ran down smartly after two hours' standing, got up this second mash smartly into the copper, taking the necessary precaution of rincing the copper out clean, for the reception of the second wort, which was boiled two hours very hard, with the remainder of the hops; these two worts were run together on the same cooler; after standing a few hours, were run on a second cooler, and there suffered to remain till they came down to 65; were then let into the tun, with two gallons of solid yest, by a large plug hole in a few minutes so as to have scarcely suffered any diminution of their heat; in twelve hours after, there was added two gallons more of yest, roused the tun a second time, came on gradually, and attenuated within 56 hours ten degrees, and so was cleansed at the heat of 75, this beer was filled every two hours, for the first twenty-four, and in a few days more became transparently fine; this beer should have added to it, before sending out, four ounces of steeped hops, and two ounces of ground rice to each barrel; the five pounds of hops wanted for this operation is previously put to steep in a clean tub with some of the beer. This beer, if thus brewed with good materials, and treated as directed, will be found to give satisfaction. During the winter half year, the fermenting tun should be always covered; in summer, only partially so; the less strong beer is attempted to be brewed in that season the better, as it will not keep, necessity alone should compel the brewer to work, in this country, during the summer months; and then at small beer only. _Table Beer, English method of brewing it._ Take 8 bushels of Malt, and 6 lb. of Hops. This quantity of materials should deliver four barrels of beer. First liquor 161; mash the first time one hour. Second liquor 170; mash the second time half an hour. Third liquor 152; mash the third time twenty minutes. Boil the three runnings together for two hours in a close covered copper; three pints of good solid yest will be sufficient to pitch this quantity, mixing it, before adding, with about one gallon of the wort, then add this to the rest; a low attenuation for this kind of beer will not answer, the specific gravity being too light, the fermentation rarely exceeding 30 hours in the tun. It being generally wanted for immediate use; it is pitched high, and worked quick. It is further important to bung it down close as soon as it has done working. This kind of beer may be securely and advantageously administered to fever patients, instead of other drink: I have known it to be attended with the happiest consequences. _Unboiled beer, how Brewed._ The following process, I confess, I never myself tried, but, from the manner it was spoken of by the party giving it, I would strongly recommend a trial of it on a small scale, at first, until its advantages and superiority was well ascertained over the old and long established mode of boiling wort. Mash your full complement of malt, or rather one third more, and that in the usual way, (suppose you are brewing strong beer,) and while your mash stands, let your copper have as much cold water run into it as will save it from burning; rouse your fire, salt and rub your hops, as recommended in previous processes; let their quantity be increased one third more than if brewed in the ordinary way; and when got into your copper, cover close, and let these hops simmer for two hours, _but not boil_; then run down your first wort in sufficient quantity as, when added to the water and the extract of the hops, will give you the length you contemplate; you will observe the malt is increased to meet the quantity of water in the copper; but this cannot be considered a loss, as the second mash will answer for single ale, or good table beer; the hops in the same way. When you have got your intended complement of strong wort in your copper, rouse it well, cover close, and let your copper stand two hours more, keeping up a moderate fire just enough to make it simmer _but not boil_; during this time your second mash may be going on with water from your second copper; this, as already stated, will make single ale, or good table beer; if the latter, it may be boiled in the usual way, but not longer than half an hour, on account of the increased quantity of hops; which hops should be all retained in the copper after the first worts are run off, by means of a strainer placed at the mouth of the cock hole; one hour strong boiling will be sufficient for the succeeding wort, if single ale be wanted; the remainder of the process for both worts is the same as already directed for such quality of drinks. It was further stated to me that unboiled beer will appear very turbid and unpromising for some time after it is brewed, and will take three months at least to come round; but that after that period it will improve rapidly, and become transparently fine; when second worts are found too weak, they may be assisted with good Muscovado sugar, of which eight pounds is considered equivalent to one bushel of malt. In fact, pleasant beer might be made from sugar alone, without any malt. _Strong Beer, of an excellent quality and flavour, brewed from the extract of the Hop only, rejecting the substance._ This extract was obtained by the hot infusion, in a close covered wooden vessel set to infuse the evening before brewing; in this process one third more hops should be allowed; these hops need not be wasted, as they will answer well for table beer, or single ale, brewed according to the preceding processes; but, in either case, one hour's strong boiling will answer for single ale, half an hour for table beer will be sufficient, on account of the increased quantity of hops. When you have got up your first wort in your copper, that you intend to preserve with extract, boil the first half hour without it, and one hour with it, very hard in both instances. It should have been mentioned that, in preparing your first, or mashing liquor, two pounds of rice is to be added to your water in the copper before boiling, supposing the length of your brewing 20 barrels, or in that proportion. Strong beer brewed with the extract alone, as here recommended, has turned out remarkably well, and if the hops are good, will be found more delicately flavoured than other beer; supposing the malt alike good. Pitching, cleansing, and filling, to be conducted as already recommended in preceding processes, with the tun close covered during the fermentation. _Table Beer._ Table beer, of a superior quality, may be brewed in the following manner, a process well worth the attention of the brewer, the gentleman and the farmer, whereby the beer is altogether prevented from working out of the cask, and the fermentation conducted without any apparent admission of the external air. I have made the scale for one barrel, in order to make it more generally useful to the community at large; however, the same proportions will answer for a greater or less quantity, only proportioning the materials and utensils. Take one peck of good malt ground, one pound of hops, put them in twenty gallons of water, and boil them for half an hour, then run them into a hair cloth bag, or sieve, so as to keep back the hops and malt from the wort, which, when cooled down to 65 degrees by Fahrenheit's thermometer, add to them 2 gallons of molasses, with one pint, or a little less, of good yest, mix these with your wort, and put the whole into a clean barrel, and fill it up with cold water to within four inches of the bung hole, (this space is requisite to leave room for fermentation,) bung down tight, and if brewed for family use, would recommend putting in the cock at the same time, as it will prevent the necessity of disturbing the cask afterwards; in one fortnight this beer might be drawn, and will be found to improve to the last. _Fermenting and Cleansing in the same Vessel._ The following recommendation to brewers is well worth their attention, that is, to ferment their strong, or what they call their stock beer, in the vat they propose to keep it in, until fit to turn out; this practice will be found advantageous to the flavour and preserving quality of such beer, as close fermentation has a decided preference over what is termed open. One or more workers may be placed in the side of such vat, a few inches above the surface of the enclosed liquor; thus the head as it rises will have the opportunity of running off; such fermentation should further be conducted coolly and slowly, the pitching heat, in this case, should not exceed 60 degrees of Fahrenheit, and the yest one third in quantity less than if applied in open vessels, but the yest should be mixed with a double quantity of the wort at 65, in a separate vessel before pitching. When vats are wanting, the operation may be conducted in hogsheads or butts, allowing a tin or wooden worker to each cask. In brewing small quantities of strong beer, this contrivance supersedes the necessity of fermenting tuns, or troughs, no small saving of expense, whilst it makes the beer more spiritous and preserving. The annexed plate shows the form and application of the worker, whether of tin or wood. A The cask in which the worker is placed. B The spout of the worker, which takes off the yest. C The plug at the angle of the worker to admit the pipe of a tundish, in order to fill the cask as it works.] _Another Method of fermenting Strong Beer that might be expected to produce a pure and excellent liquor._ Mash, run down, and boil in the usual way, suffer your worts, after drawing your fire, to remain on your copper two hours, doors and hatch open. If in winter, the deeper your worts lie on the cooler the better; when they have come down to the proper heat of pitching, give your yest to them on the cooler, mixing it gently with the whole guile, and when properly headed with yest, which will probably happen within twenty-four hours, run off your worts gently into barrels, leaving your top and bottom yest on the cooler undisturbed, till all the cooler is cleared; but previous to running your worts into the barrels, put half a pint of good solid yest into each, and when full, clap your tin workers into the bung holes, and so let it finish its fermentation for about a week longer, filling the casks occasionally as they work. When done working, bung down or vat them; if you wish to add any kind of flavouring substance to this beer, the best time to do it is at commencing the second fermentation, experience teaching that all fermented liquors should have such substances added to them during, or at the commencement of their fermentation, which is preferable to adding these substances in the boil; I mean spices, and delicate flavouring substances. _Process of Brewing Windsor Ale on a small scale._ Windsor ale is a very pale, light, agreeable ale, as fine as wine, and unquestionably the best fermented of any malt liquor sent to the London market. Length drawn, three barrels per quarter of eight bushels, the malt pale, with two pounds of hops of the first quality; heat of the first liquor 182, two barrels of which is generally allowed to each quarter of malt, for the first mash; one barrel per quarter for the second; the same quantity for the third is as little liquor as can be dispensed with in three mashings; for short liquor and stiff mashes are essential to this quality of ale, in order to leave as little as possible in the copper for evaporation on account of the short boiling. Mash quick, run down quick, get your wort as fine as possible into your underbank; let your first mash stand two hours, your second one hour and three quarters. Give your second mashing liquor at 190; if you mash a third time, give your liquor at 175; stand half an hour; these worts should be pitched from 52 to 60, but not higher. The mode of doing so is also different from the generality of other malt liquor; your yest should be fresh, smooth, and solid. Begin yesting this ale a few barrels at a time, and when that has caught, add the remainder gradually, in about 48 hours, or from that to 60. This guile of ale will assume a close head of yest, which should be carefully skimmed off as fast as it forms after the first skimming: by this is not meant the first or worty head formed soon after the yest has taken, but the close yesty head already mentioned, which usually takes the time stated, say from 48 to 60 hours, when no more yest rises, and the guile remains quite flat; you will find the heat you pitched at, say 56, 58, or 60 degrees will by this time have increased to 80, or even more, and the specific gravity of the wort diminished from 26 or 27 pound per barrel, to six or seven pound per barrel; this attenuation will give it all the pungency and spirituosity it stands in need of. At this time your cleansing operation commences; after which it will work but little in the casks. It should be filled regularly every two or three hours, after cleansing, for the first twenty-four. After it has done working, you should immediately start it into an air-tight vat, with about one pound of hops well rubbed to every three barrels of ale in your brewing; if you use spent hops, such as has been boiled on the first mash, you may use a greater quantity, say half a pound more to each three barrels of beer, taking the precaution that they are become quite cool. This ale, thus treated, will be found glass fine in the course of a fortnight, and fit to be racked off into hogsheads or barrels. It will improve by age both in flavour and quality. But it should not be boiled more than fifteen minutes. _Reading Beer, how made._ Reading beer is made in a town of that name about thirty miles distant from London; the quality of its beer is much spoken of, the mode of brewing it is stated to be as follows: Scale of Brewing, suppose 22 Barrels. 80 Bushels of Pale Malt. 98 lb. of Hops. 3 lb. of Grains of Paradise, pounded or ground. 5 lb. of Coriander Seed, do. 14 lb. of the best brown Sugar. Your malt should be some days ground, and if exposed on an open loft, after grinding, so much the better. Boil your first copper, run on your mash tun till you have your complement, then occasionally rouse your water with your mashing oars, or dashers, till you get it down to 175: put your malt in slowly, for fear of setting; keep mashing all the time, which should be continued full one hour, stand two hours, run your worts, when you set tap, as fine as you can get them into your underbank; this you will effect by drawing off successively five or six buckets of the first run, and throwing them over your grains in the mash tun; when you perceive they come off glass fine, lay by your bucket. Give your second mashing liquor at 178 degrees, mash three quarters of an hour, stand one hour. Give your third liquor at 158, mash half an hour, stand one hour; boil your first copper of worts, which should take the half of your three runs, one hour as hard as you can; your second, two hours in the same way; run the two boilings into one cooler, and pitch at 64, giving one gallon of solid smooth yest; skim off the yest, as in the case of Windsor ale, until the attenuation rises to 80 degrees, which will have advanced it, from the pitching heat of 64, sixteen degrees. Before you commence the operation of cleansing, mix one quarter of a pound of bay salt, with half a peck of malted bean flour, scatter this mixture over the surface of your tun, rouse well, cleanse, and fill in the usual way. _Two-penny Amber Beer, as brewed in London._ This beer is in great demand, and large quantities of it consumed, and is supposed more profitable to the brewer than any other species of malt liquor, it being generally brewed, drank, and paid for within the fortnight. PROCESS. 200 Bushels of Pale Malt. 112 lb. of Hops. 20 lb. of Liquorice Ball 30 lb. of Molasses, 4 lb. of Grains of Paradise, ground. Cleansed 81 Barrels. Heat of first mashing liquor 169; mash one hour, stand two hours, run down smartly; specific gravity of this wort 26 pound per barrel; second mash 170, mash half an hour, stand one hour, run down as before; specific gravity of this wort 11 pound and a half per barrel; third mash 160, mash twenty minutes, stand half an hour; gravity six pound per barrel; divide these three runnings into two boilings; boil the first copper for three quarters of an hour, the second one hour, in both cases as hard as possible; the hops and other ingredients should be put in at the first boil, and so retained in the copper by means of a strainer; pitch these worts at 64 degrees, giving two gallons of solid yest at first, with two gallons more in twelve hours after: remained in the tun about 60 hours, or until its attenuation reached 80 degrees; used over the surface of the tun, before cleansing, four pound of ground ginger, half a pound of bay salt, and about half a peck of wheaten flour, mixed all together, and scattered over the surface of the tun; roused well, and cleansed 81 barrels. This quality of beer, when brewed from good materials, and managed as directed, makes a wholesome and a pleasant beverage; but, to do it justice, should have more time allowed it for coming to perfection. _London Ale, how brewed._ Ale is, of all other malt liquor, the most delicate, and will bear less tampering with. It will therefore require your nicest care through every part of the process. Transparency, pungency, and flavour, are qualities that highly recommend this liquor, and should be particularly aimed at by the brewer. Hard water is, by some, supposed to be more favourable for making this kind of ale than soft. Heat of the air 60 degrees. 200 Bushels of Pale Malt 206 lb. of Hops. 4 lb. of Grains of Paradise, pounded or ground. 4 lb. of Coriander Seed, do. 1 lb. of Orange Powder, do. Cleansed 65 Barrels of Beer. First mash 173, mashed one hour, stood one hour, ran down smartly; specific gravity of this wort 32 pounds per barrel; the heat appears more favourable for obtaining the whole sweet of the mash than the preceding one by six pounds per barrel, an object well worth the attention of the brewer; second mash 172, specific gravity of this wort 22 pounds per barrel; mashing, standing, &c., the same as in the preceding process; boiled the first wort one hour; the second wort two hours, very hard in both instances; pitched the tun at 62 degrees giving two gallons of yest at first, and two gallons twelve hours after. Remained in the tun about 80 hours, or until it attenuated to 74, or twelve degrees over the heat it was pitched at; used over the surface of the tun, at cleansing, four pound of ground ginger, half a pound of bay salt, with half a peck of wheat flour well mixed, roused the tun well. You should observe, in working amber beer, to cleanse with the sweets on, but in ale you should work it low in order to get the sweets off. This ale should be carefully filled as it works and closely attended to until done working; then put into each cask, if of a large size, two handfuls of spent hops, that have been previously cooled, and but a short time boiled; then bung down, and it will be fit to send out. _Windsor Ale, brewed on a large Scale._ This ale has experienced so great a demand in London and its vicinity for a few years back, as materially to affect the London pale beer brewery; it is a liquor better calculated for winter than the summer season. The London brewers have been induced to brew on the same principle, and in many instances they exceed the original. Here follows the London process for brewing this kind of beer, which, I apprehend, will be well worth the American brewers' imitation, as good ale is a species of malt liquor rarely met with in this country. 200 Bushels of Pale Malt. 224 lb. of Hops. 40 lb of Honey. 4 lb. of Coriander Seed, ground. 2 lb. of the Grains of Paradise, ground. 65 Barrels Cleansed. Procure your hops of the best quality, rub them in one or more large tubs, pour cold water on them in sufficient quantity to wet them all over, and so let them infuse till the next day, which should be the day on which you brew. When your first copper has just boiled, run a sufficient quantity of water into your mash tun for your first mash; and when this has cooled down to 176 degrees, run in your malt slowly, and mash well for one hour and a quarter; after which, let your mash tun stand two hours, run down smartly and fine; keep your mash tun close covered from the time you have done mashing till you begin to set tap; give your second mashing liquor at 186, mash one hour, stand one hour, run down as before; give your third liquor for the last mash at 160, mash one hour, stand one hour run down as before; divide these three worts into two parts, boil your first copper one hour, putting in your ingredients with your hops, save the 40 pounds of honey, which should be reserved to be put into the copper a few minutes before striking off; rouse your copper well at the time of putting in the honey, and continue the same till run off, otherwise, it will pitch to the bottom of the copper, and likely be the cause of burning; your second worts should boil two hours on the same hops and ingredients, which should be retained in the copper by a strainer, pitch your tun at 62 degrees, giving two gallons of good yest at first, and two gallons more in twelve hours after; let your fermenting heat rise to 80 degrees; thus your attenuation will have gained 18 degrees, which will probably cause your guile to remain in the tun from 60 to 80 hours. Use salt and bean meal flour as directed in the preceding process, and in the same proportion, before cleansing; fill, &c., as already directed. _Welsh Ale, how brewed._ This it a luscious and richly flavoured ale, much liked, but very heady. PROCESS. 72 Bushels of Pale Malt. 70 lb. of Hops. 20 lb. of best brown Sugar. 2 lb. of Grains of Paradise, ground. Heat of the first mashing liquor 175, mash one hour and a half, putting in your malt very gradually, and mash uncommonly well, and let it stand two hours; second liquor at 190, mash one hour, and stand two more; run down as before, boil these two runs together for one hour and a half, putting in your hops, &c., save the sugar, which is to be put in but a few minutes before striking off, at which time the rousing of the copper should commence, and so continue until the worts are nearly run off. Small beer may be brewed, in the usual way, after both these worts, in which case, cold water will answer full as well as hot; pitch your strong worts at 62, with a small proportion of good yest, and let your fermenting heat rise to 80; thus your attenuation will proceed 18 degrees; cleanse with salt and bean flour as already directed, but in suitable proportion in point of quantity to your malt, fill in the usual way, and when nearly done working, use fine ale to top with, before you bung down, putting into each barrel one large handful of scalded hops, that have been previously cooled down. _Wirtemberg Ale._ BREWED AS FOLLOWS: 128 Bushels of Pale Malt. 32 Bushels of Amber Malt. --- 160 Bushels of Malt. --- 188 lb. of Hops. 28 lb. of Honey. 20 lb. of Sugar. 4 lb. of Hartshorn Shavings. 4 lb. of Coriander Seed, ground. 1 lb. of Caraway Seed, ground. Cleansed 50 Barrels of Ale. Give your first mashing liquor at 172, mash for one hour and a half, stand two hours, run down fine, but smartly. Second mashing liquor 180, mash one hour, stand two hours, run down as before; get up your two worts; put in, with your hops, the other ingredients, save the honey and sugar, which is to be put into your copper but a few minutes before striking off, rousing your copper while any wort remains in it. This ale should be boiled hard for one hour and a half; pitch your tun at 62, raise your fermenting heat to 80, which will generally rise in the course of 70 hours. Give of good solid yest four gallons, two gallons at first, and two gallons more in twelve hours after, rouse your tun each time. _Hock._ This is a beer that has within a few years had a great run, particularly in Germany. PROCESS AS FOLLOWS: 112 Bushels of Pale Malt. 48 Bushels of Amber Malt. --- 160 Bushels. --- 206 lb. of Hops. 4 lb. of Cocculus Indicus Berry, ground. 2 lb. of Fabia Amora, or Bitter Bean. 20 lb. of Brown Sugar, of good quality. Cleansed 54 Barrels. First liquor 176, mash one hour and a quarter, stand one hour and a half; second liquor 182, mash one hour, stand two hours; when both worts are in the copper, add your hops and other ingredients, except the sugar, which is to be put in as already directed a little time before striking off, boil two hours and a quarter as hard as you can. Pitch your tun at 64, giving four gallons of solid yest at once, and cleanse the second day, or in forty-eight hours; fill as already directed, and put into each barrel one handful of fresh steeped hops before bunging down. _Scurvy Grass Ale._ This species of ale is considered a great sweetener of the blood, has been much approved of, and is strongly recommended as a wholesome and pleasant medicine. PROCESS AS FOLLOWS: 40 Bushels of Pale Malt. 25 lb. of Hops. 10 lb. of Molasses. 2 lb. of Alexandrian Senna. 5 Bushels of Garden Scurvy Grass. Cleansed 14 Barrels of Ale. Your malt should be fine ground; give your first liquor at 170, mash one hour, stand one hour; heat of your second liquor 172, mash three quarters of an hour, stand one hour; give your third mashing liquor at 160, mash twenty minutes, stand half an hour; these three worts should be run into your copper together, and boil together for one hour gently, for one quarter of an hour more as hard as you can; all your ingredients to be put in with your hops, except the molasses, which should only be put in a few minutes before striking off; from the time you put in your molasses, keep stirring your copper until its contents is nearly off. About the middle of your fermentation, procure one pound of horse-radish, wash it well, dry it with a cloth, after which slice it thin, and throw it into your tun, rousing immediately after; when done, replace your tun cover, pitch your worts at 66 degrees, with about two gallons of solid yest; cleanse the third day, with the sweets on. This ale is drank both hot and cold. _Dorchester Ale._ This quality of ale is by many esteemed the best in England, when the materials are good, and the management judicious. 54 Bushels of the best Pale Malt. 50 lb. of the best Hops. 1 lb. of Ginger. 1/4 of a lb. of Cinnamon, pounded. Cleansed 14 Barrels, reserving enough for filling. Boil your copper, temper your liquor in the same to 185, and when ready, run it on your keeve a little at a time, putting in the malt and the water gradually together, mashing at the same time; when the whole of your malt is thus got in, continue the operation of mashing half an hour, cap with dry malt, and let your mash stand one hour and a half. Second liquor 190, mash three quarters of an hour, stand two hours; in both mashes get your worts as fine as you can into your underbank; rub and salt, before mashing, 30 pounds of your hops; infuse them in boiling water before mashing, and let the vessel containing them be close covered. The other twenty pounds of hops should have been rubbed the evening before brewing, but not salted, put into another close vessel, covered with boiling water, and there suffered to digest for 12 hours: at the time of putting the hops in your copper, the extract, in both cases, is to be added; but the first 30 pounds of hops in substance _only_ to be added; these, with the two extracts will be sufficient for the brewing; the remaining 20 pounds of hops will answer for single ale, or table beer, but should be used on the same day. Your worts being now in the copper, with the hops and extract, boil hard for one hour; after which, draw your fire, open your copper and ash-pit doors, and so let it stand one hour, then strike off gently on your cooler; when your worts are cooled down to 55, prepare your puncheons, suppose four, containing four barrels each; see that they are dry, sweet, and clean; take three pints of solid yest for each puncheon, to which you should add three quarts of the wort at 65, mix and blend the wort and yest together, putting this proportion to each cask, containing four barrels, then fill up with the wort, at the heat of 55, already mentioned; put in your tin workers, one into each puncheon, and when you perceive it begins to work freely, which probably will not be till the third or fourth day, begin to fill up your casks, and so continue doing from time to time, till they have done working. (The tin worker is described in page 139.) This mode of brewing appears to be peculiarly adapted for shipping to warm climates; the fermentation being slowly and coolly conducted: it is also well calculated for bottling. Table beer may be made, after this strong, of good quality, with cold water, if not over drawn; 10 pound of the steeped hops will be sufficient to preserve this beer; one hour's boiling will be enough; ferment as already directed, and add six pounds of sugar just before striking off, rousing, as already directed, while any remains in the copper. _Porter._ In England, is a liquor of modern date, which has nearly superseded the use of brown stout, and very much encroached on the consumption of other malt liquors, till it has become the staple commodity of the English brewery, and of such consequence to the government, in point of revenue, that it may be fairly said to produce more than all the rest. Porter, when well brewed, and of a proper age, is considered a wholesome and pleasant liquor, particularly when drank out of the bottle; a free use is made of it in the East and West Indies, where physicians frequently recommend the use of it in preference to Madeira wine: the following three processes are given under the denomination of No. I., II., and III., the first and second of which I knew to be the practice of two eminent houses in the trade. The third I cannot so fully answer for. An essential object to attend to, in order to ensure complete success to the porter process, is the preparation of the malt. Directions for that purpose will be found at the end of these processes. _Porter Process._ No. I. MATERIALS. 186 Bushels of Pale Malt. 94 Bushels of Brown Malt. --- 280 Bushels of Malt. --- 300 lb. of Hops. 10 lb. of Gentian Root, sliced. 10 lb. of Calamus. 10 lb. of the essence of Gentian. Cleansed 121 barrels. The hops, with the other ingredients, to be put in with the first boil, and retained in the copper by wire strainers, or otherwise, for the succeeding worts. First mashing liquor 165, mash one hour, stand one hour, run down smartly; second mash 170, mash one hour, stand one hour, run down as before; third mash 180, mash half an hour, stand half an hour, run down smartly; divide these three runs into two boilings, boil your first copper as hard as you can for half an hour, the second for three hours as hard as possible; pitch your first wort at 65 degrees, with 10 gallons of smooth yest; pitch your second at 70 degrees, with six gallons, both runs to mix in the same tun, as soon as the head of your tun begins to fall and close, which will possibly happen from thirty to forty hours, at which time it is expected the fermenting heat will rise to 80, but in no case should it be suffered to exceed it; two pecks of bean meal flour, with two pounds of bay salt mixed together, should be evenly scattered over the surface of the tun, before cleansing, and then well roused. After cleansing, this drink should be filled every two hours, for the first twelve fillings, after which, twice a day will be sufficient; and, in about a week after cleansing, porter so brewed, and treated as here directed, will be glass fine, and in a week more may be vatted. As porter is generally sent out in iron-bound hogsheads of seventy gallons each, there should, at the time of going out, be three half pints of finings, with as much heading mixed through the finings at will go on a two shilling piece; this fining and heading should be well stirred in the hogshead by means of a fining brush used for the purpose, with a long iron handle; treated thus, porter will fall fine in a few days. The faster draught porter is drawn off the cask the better it will drink; for when too long, it is apt to get flat, and sour. _Porter Process._ No. II. 160 Bushels of Pale Malt. 120 Bushels of Brown Malt. --- 280 --- 350 lb. of Hops. Cleansed 121 Barrels of Porter. Heat of the first mashing liquor one hundred and seventy-two, mash one hour, stand one hour, run down smartly; second mashing liquor one hundred and eighty, mash one hour, stand two hours, run down as before; third mash one hundred and sixty-four, mash half an hour, stand half an hour, run down smartly; boil the extract of the first, with half the extract of the second mash; boil as hard as you can for one hour and a quarter, then strike off, retaining your hops in the copper for your second boil, which includes half your second wort, and the whole of your third; these should be boiled for four hours as hard as you can make them; pitch your first wort at seventy, or so high that, when in the tun, it will make up at sixty-four, to which give six gallons of smooth yest; pitch your second wort at sixty-five, giving seven gallons more of yest; when all your worts are in your tun, it should make up at sixty-four. Thus managed, it will be fit to cleanse in thirty-six or forty hours; the closing and falling in of the head will direct the period of performing this operation; fill, &c., as in the foregoing process. _Porter Process._ No. III. 88 Bushels of Pale Malt. 102 lb. of Hops. 12 Gallons of Essentia Bina, or sugar colouring. Cleansed twenty-seven and a half Barrels of Porter. First mashing liquor one hundred and sixty, mash one hour, stand one hour; second mashing liquor one hundred and seventy, mash one hour, stand one hour and three quarters; third mashing liquor one hundred and seventy-five, mash half an hour, stand one hour; divide these three runs into two equal parts, boil the first one hour, the second two hours and a half, as hard as you can in both instances; pitch your first wort at sixty, giving two gallons of solid yest; your second at sixty-five, giving the same complement of yest; let your fermenting heat rise to eighty, then cleanse, first topping your tun with two pounds of bean meal flour, and half a pound of bay salt pounded and mixed with the flour; fill fine, and head your porter casks, as already directed to do with hogsheads; let your finings and heading be in that proportion with lesser casks. _Porter Malt._ This species of malt should be made from strong, well-bodied barley, the process exactly the same as for pale malt, until it is about half dried on the kiln; you then change your fuel under the kiln from coak or coal to ash or beech wood, which should be split into small handy billets, and a fierce, strong fire kept up, so as to complete the drying and colouring in three hours, during which time it should be frequently turned; when the colour is found sufficiently high, it may be thrown off; the workmen should be provided with wooden shoes, to protect their feet from the uncommon heat of the kiln in this last part of the process, which requires the grain to snap again from the excessive heat of the kiln. For the better performing this part of the process, I would recommend a wire kiln to be placed adjoining the tiled one, from which it may be cast on the wire; this would be a better and more certain mode of conveying the porter flavour to the malt, than if the drying was finished on the tiled kiln. Where a wire kiln was thought too dear, a tiled one might be made to answer. _Porter Colouring._ In modern language, is termed _essentia bina_. This is made from brown sugar, and is now generally substituted by the London brewers for porter malt, as more economical, and full as well calculated to answer all the purposes of flavour and colouring. Muscovado, or raw sugar, with lime water, are the usual ingredients of this colouring matter. Another kind, of inferior quality, is prepared from molasses, boiled until it is considerably darker, bitter, and of a thicker consistence; and when judiciously made, at the close of the boiling, it is set on fire and suffered to burn five or six minutes, then it is extinguished, and cautiously diluted with water to the original consistence of treacle. The burning or setting on fire gives it the greater part of its flavour, which is an agreeable bitterness, and burns out the unassimilating oil. Muscovado, or raw sugar, when treated in a similar manner, and diluted to the same consistence before it sets, obtains a bitterness that more nearly strikes the porter flavour on the palate; it is of a deep dark colour, between black and red. To prepare it to advantage, take three pounds, or three hundred weight of Muscovado sugar, for every two pounds, or two hundred pounds, of essentia bina intended to be made, put it into an iron boiler set in brick work, so that the flue for conveying the smoke of the fire into the chimney, rises but about two thirds of the height of the boiler in its passage to the chimney. The boiler should have a socket or pivot in the centre of its bottom to receive the spindle of wrought iron, with a crank in it, above the brim of the boiler, the upper end of which turns on a corresponding pivot in an iron bar fixed across several feet above the boiler, with a transverse iron arm to reach from the crank for some feet over the boiler for a man to stand, and turn it with its scraper of iron also, which works on the bottom of the boiler to keep the sugar from burning on the bottom before the upper part melts; this arm may be placed in a wooden handle at the end, and held by the man, lest it become too hot for his hand. Put one gallon of pure water into the boiler with every hundred weight of sugar to be employed, that is, one pint to every fourteen pounds weight of sugar, then add the sugar, light the fire, and keep it stirring until it boils, regulating the fire so as not to suffer it to boil over; as it begins to lessen in quantity, dip the end of the poker into it, to see if it candies as it cools, and grows proportionably bitter to its consistence; mark the height of the sugar in the boiler when it is all melted, to assist in judging of its decrease; when the specimen taken out candies, or sets hard pretty quickly, put out the fire under the boiler, and set the vapour or smoke arising from the boiler on fire, which will communicate to the boiling sugar, and let it burn for ten or twelve minutes, then extinguish it with a cover ready provided for the purpose, and faced with sheet iron, to be let down on the mouth of the boiler with a chain or rope, so as exactly to close the boiler. As soon as it is extinguished, cautiously add _strong lime water_ by a little at a time, working the iron stirrer well all the time the water is adding, so as to mix and dilute it all alike to the consistence of treacle; before it sets in the boiler, which it would do, as the heat declined, in a manner that would give a great deal of trouble to dilute it after, and be imperfectly done then, it is easy to conceive this kind of work requires to be done in an open place, or out-house, to prevent accidents from fire. If the _essentia bina_ is neither burned too little nor too much, it is a rich, high-flavoured, grateful bitter, that preserves and gives an inimitable flavour and good face to porter; to be added in proportion as the nature and composition of the grist is varied with a greater or less proportion of pale malt. _To convert old hock into brown stout_, it will take three pounds of _essentia bina_ of middling or ordinary kind, and but two pounds of the best made from Muscovado raw sugar as directed, it should weigh ten pounds to the gallon. The _essentia bina_ should be mixed with some finings, and roused into the tun soon after the yesty head gathers pretty strong, in order to undergo the decomposing power of fermentation, part of it being prone to float on the surface of the beer under the form of a flying lee. When employed in the usual way of colour, with this precaution, the colouring and preserving parts unite with the beer, and the gross charry parts precipitate with the lees, and other feculencies in the tun, previous to cleansing, adding a firm and keeping quality to the beer. Lime water for diluting the burnt sugar, in the proportion of _essentia bina_: thirty pounds of lime will make one puncheon, or one hundred and twenty gallons of lime water: put fresh lime from the kiln, previously slaked into coarse powder, into an airtight cask, gradually add the water, stirring up the lime to expose a fresh surface to the solvent powers of the water, which will rarely dissolve more than one ounce troy weight in the gallon, or retain so much when kept ever so closely excluded from the external air. If Roche lime was first grossly pounded, and slaked in the cask, the lime water might be made still stronger; the reason for directing the water to be slowly and cautiously added at the first, is for the more conveniently mixing the lime with the water, which otherwise would not be properly wet. Do not fill the vessel within a few gallons of the bung-hole, that it may be rolled over and over with effect, fifteen or twenty different times before left to settle, in order to have the water fully saturated with the lime; when settled it should be perfectly clear. It is important, as well at necessary to state, that when the lime water is about to be added to the _essentia bina_ in the kettle, it should be hot, otherwise there would be danger of cracking the cast iron, of which the kettle is composed, as well as causing a partial explosion and waste of the sugar when coming in contact with the cold medium of the lime water; this precaution should be carefully attended to. _Strong Beer._ Process for brewing strong beer, alleged to be the practice in Switzerland, by which it is asserted that an excellent and preserving beer will be produced. I would recommend a small experiment to be made at first, in order to establish its character and success on a more extended scale. At a first view, there appears to be one serious objection to this process, and that is, that it requires but a small quantity of oily or fatty matter to destroy the fermentation of any guile of beer. In answer, it may perhaps be truly said, that the precaution of skimming off the fatty matter, as it rises on the surface of this beer while in the copper, as well as the time allowed it there to settle, also, its straining through the hops before getting on the cooler, gives another chance to deposite this matter in the hops, if any should remain in the copper after the skimming off. PROCESS AS FOLLOWS: 60 Bushels of Pale Barley Malt. 20 Bushels of Pale Wheat Malt. --- 80 Bushels. --- 170 lb. of the best Hops, to be rubbed, salted, and steeped in one or more close vessels before mashing, or the evening before brewing, still better. 54 lb. of lean Beef to be put into the copper with the worts, this will average two pounds to the barrel. 7 lb. of Rice, also, to be put in with the Beef. 1 lb. of ground Mustard to be put in with the Hops. Cleansed 27 Barrels. These worts are to be boiled one hour without the hops, in order to afford the greater facility of skimming the fat off the surface. After they have boiled the first half hour, the fire is damped, the boil left to subside, and the copper to be then carefully skimmed. (This points out the necessity of an open copper for this operation.) After which, the fire is started again, and the worts made to boil another half hour, and skimmed a second time in the same way; after which the hops and mustard are added with three gallons of the _essentia bina_, and then boiled for one hour and a half, as hard as the copper will allow without boiling over or wasting; the fire is then drawn, ash-pit and copper doors left open, the copper covered, and suffered to stand two hours, then struck off on the hop back. The temperature of the external air at the time you brew this quality of beer should not be higher than fifty degrees. Your first, or mashing liquor, should boil, then run your whole complement into your mash tun, which when cooled down to one hundred and sixty-five, begin putting in your malt, one sack at a time, and mash for one hour and a quarter, stand one hour, run down as fine as you can, yet smartly; second mash one hundred and eighty-five, need not boil, but when brought to that heat in your copper, begin mashing, and mash well for three quarters of an hour, stand two hours; boil, skim, and hop, as already directed. It is to be understood that the produce of these two mashes are to be boiled together, forming a clear length, when cleansed, of twenty-seven barrels; pitch your worts at sixty, previously mixing in a tub, fifteen gallons of your wort at seventy, with one gallon of solid yest, some time before pitching, which will give it time to catch before adding to the remainder of the wort. Twelve hours after another gallon of pure yest is to be added, and the tun well roused, then covered; the attenuation suffered to proceed to eighty degrees, _but not higher_. This mode of pitching worts might be successfully applied to other qualities of beer and ale, and will be found a safe and good process. _Filtering Operation._ (With a Plate.) [Illustration A The fountain. B B The cocks. C The trunk communicating with the space between the two bottoms. D The filtering tub. E The false bottom. F The spout for carrying off the ascending liquor. G The receiver of the filtered liquor by ascent. H The receiver of the filtered liquor by descent.] This simple operation, if my view of its effects on malt liquors, as well as other fermented liquors, be correct, will do more towards their improvement and preservation, than any thing hitherto attempted to be tried on them, after their fermentation has been completed; and for this plain reason, that it will at once disengage them from all fermentable matter, and render them transparently fine and preserving; thus immediately fitting them for the bottle, or putting up into tight casks, for home consumption or exportation, which will soon recover the beer or ale so treated from the flatness that will necessarily be induced by a long exposure to the air during the continuance of the operation; further to remedy which, I would recommend putting into each barrel, before the cask is filled with this beer, half a pound of ground rice, then fill, bung down tight, and in a short time briskness and activity will be restored to the liquor, whether intended for draft or bottle. This mode might, with equal success, be applied to every kind of fermented liquor, particularly to cider, wine, and perry, also to river and rain water. There are two modes of filtration, one by descent, the other by ascent; the latter operation seems to be the most perfect, though not the most economical or expeditious. The preparation of the filtering medium is as follows. Your filtering vessel should be in proportion to the scale of work you intend operating on. The vessel containing the filter, should have the form somewhat of an inverted cone, in proportion wider at top than at bottom; over the bottom of this vessel should be placed a false one, about three or four inches distant from the other; this upper bottom should be perforated with holes, rather large bored, at the angles of every square inch of its surface; your fake bottom being laid, provide two pieces of clean thick blanketing the full size of the vessel, lay these pieces one over the other, over them a stratum six inches deep, of rather coarsely pounded charcoal; this should be previously wetted with some of the beer or ale, till brought to the consistence of coarse mortar; over this lay another stratum of fine clean pit sand, and so on, stratum super stratum, of sand and charcoal, till you have reached within six inches of the top; the cover of this vessel, which is also perforated with holes somewhat smaller than those of the bottom, is let down in the vessel to within one inch of the filtering medium, and in that position is well secured by buttons, or otherwise. When you filter by descent, you run your liquor over this cover, which, by means of the holes, will be distributed evenly over the upper surface of the filter; and so you continue running on your liquor as fast as you see the operation will take it. When you wish to filter by ascent, you introduce the liquor to be filtered between the two bottoms. As the fountain which supplies this liquor is higher than the filtering vessel, it will naturally force its way through the false bottom, filtering medium, &c., until it runs off pure at spout F into the receiver G. Those persons who live on the banks, or in the vicinity of our great rivers, such as the Missouri, Ohio, Mississippi, &c., may purify their drinking water in this way, with great advantage to their health, and consequent increase of comfort to themselves and families. It is also well adapted to the use of those who navigate these waters, particularly such as proceed in steam-boats, where convenient room can be always found for such useful and salutary purposes, and to them I strongly recommend its use. It may also be advantageously applied to filtering rain water, which, to some constitutions, may be more congenial than either spring or river water. _Returned Beer, to make the most of, and double its value._ Suppose, for example, you have one hundred and fifty barrels of this beer, (or in that proportion, adjust your mixing ingredients accordingly,) put the whole into one vat that it will fill; then take half a barrel of colouring, twenty-eight pounds cream of tartar, twenty-eight pounds of ground alum, one pound of salt of steel, otherwise called green copperas, with two barrels of strong finings; mix these ingredients well together, put them into your vat, and rouse well; after which, let the vat remain open for three days; then shut down the scuttle close, and sand it over; in one fortnight it will be fit for use; your own good sense will then direct its application. _To bring several sorts of Beer which have been mixed to one uniform taste._ EXAMPLE. Suppose you have one hundred barrels of this description in your vat; take six pounds of porter extract, six pounds of orange peel, ground, one pound of heading, composed of half a pound of alum, with half a pound of green copperas mixed, six pounds of Indian bark; mix these ingredients with one butt of finings, rouse your vat well, let it remain open three days, then close down your vat, and sand it over; it will be fit in one fortnight to use. _Finings, the best method of preparing them._ A very important object indeed, is finings in the management of porter and brown beers, and sometimes the paler kinds need their agency before they will become transparently fine: without this quality no beer can be acceptable to the consumer, and should be always a particular aim of the brewers to obtain. Take five pounds of isinglass, beat each piece in succession on a stone or iron weight, until you find you can conveniently shred it into small pieces, and so treat every piece until you have got through the whole; thus shredded, steep it in sour porter or strong beer that is very fine, then set the beer and the isinglass on the fire, and there let it remain till you raise the heat to one hundred and ninety, but no higher, keeping it, while on the fire, constantly stirring; then have your hogshead of clear beer ready, strain your dissolved isinglass through a hair sieve into it, which you must take care to mix well; thus assimilated it will be fit for use in twelve hours. It is worth remarking, that at the time of sending out porter or brown beer to your customers is the time to put in both your fining and heading, the jolting it then gets in the carriage will assist its fining more effectually, after it has rested a few days in the customer's cellar. _Heading._ Is variously composed, and differently prepared; what is here recommended will be found safe and effectual. Porter, or brown stout, when intended for draught, should never be sent out in the cask without fining and heading; the usual practice is to put your heading into your fining, and so both into the cask just before filling up and bunging down. The proportion for one hogshead of sixty-three gallons is three half pints of fining, with as much heading put into the fining as you can take up upon a cent piece; the heading here recommended is composed of equal parts of sal martus (or green copperas) and alum, both finely powdered and mixed in equal parts, so as to be intimately blended with each other before using. The advantages derivable from heading are merely apparent, giving a close frothy head to the beer in the quart or mug it is drawn in; supporting the vulgar prejudice, that such beer is better and stronger than that where no such appearance manifests itself. _Bottling Beer._ This is a branch of trade, that, under proper management, might be made very productive and profitable, whereas, in the manner it is now generally conducted, proves a losing one, occasioned by the great breakage of bottles, arising from the impure state of the beer at the time of putting into bottle. In consequence of this bad management, I have known a person, extensive in the trade, to lose on an average from two to three dozen bottles, as well as beer, on every hogshead he put up which happened to lie over till summer, or was bottled in that season; this loss was too heavy to expect much profit from a business so conducted; to obviate both these consequences, I would recommend beer, ale, and porter, intended for the bottle, to be carefully filtered through charcoal and sand, as directed in the operation of filtering; being thus purified from all its feculencies and fermentable matter, it will be in the best possible state for taking the bottle, in that mild and gentle way that will not endanger the loss of one or the other. It will further have the good effect of recovering the beer or ale, thus filtered, from the flatness that will necessarily be induced by that operation, giving the liquor all the briskness and activity that can be wished for. If beer, porter, or ale, be intended for exportation to a warmer climate than our own, the operation will be found particularly suited to it. Choose your corks of the best quality, and steep them in pure strong spirit from the evening before you begin your bottling operation; this precaution is essentially necessary to all beer intended to be shipped, or sent off to a warmer climate than our own, such as the East and West Indies, South America, &c. In more temperate climes, the simple precaution of filtering alone will be found to answer every necessary purpose, without steeping the corks in spirits. But suppose you bottle for home consumption, in that case you will naturally wish to have your beer, ale, and porter, get up in the bottle in as short a space of time as possible, in that case you should pack away your bottles in dry straw in summer, in sawdust in winter, as your object at that season will naturally be rather to accelerate than retard fermentation; here you should carefully watch its progress from day to day, by drawing a bottle from the centre of the heap, as nearly as you can get at it; place this bottle between you and the light, and if you perceive a chain of small bubbles in the neck of the bottle, immediately under the cork, you may conclude your beer is up in the bottle, then draw a few more bottles, and if the same appearance continues in them also, it is time to draw all your bottles from the heap they were originally packed in, and set them on their bottoms in a square frame ten inches deep, size optional; fill up this frame with the bottles of porter, or ale, so drawn in a ripe state, then get one or more bushels of bay salt, and scatter it as evenly as you can over the bottles, until the space between their necks is nearly half filled; then another course of bottles may be sunk between these, with their necks down through the salt, so as to form an upper tier; thus treated, not a single bottle will be found to break from the force of fermentation, and the salt will answer for a fresh supply of bottles, as often as you may find it necessary to draw, or send them out, this quantity will answer your purpose for years, if you only keep it dry; another advantage, and no small one, derivable from a bottling operation conducted in this way, will be, that a loft will be found more convenient for the purpose than a ground floor, as less damp, and more likely to preserve the salt dry, which a more moist atmosphere would naturally dissolve. The practice here recommended may, with equal success, be applied to cider and perry. _Brewing Coppers, the best method of setting them._ This article, at a first view, may not appear to have much connexion with brewing, but, when attentively considered, it has a very material one, as also with economy, by saving nearly one half the fuel. It is a well-known fact in brewing, that the quicker and stronger the operation of boiling is performed, the better such beer will preserve, and the sooner it will become fine; although this opinion is combated by many, experience has proved it in my practice. I will suppose the copper you are about to set to contain two thousand gallons, the diameter of its bottom, five feet; let your fire blocks, if possible, be of soapstone, one for each side, and one for the end, of sufficient thickness and length, and full twelve inches deep, to the top of your sleepers; three courses of brick, sloped off from the top of the fire stone, with the usual quantity of mortar, and plastered over, will afford sufficient elevation for the fire to act on the bottom of the copper, leaving a space of about eighteen or twenty inches from the bottom to the top of the sleepers; the breadth of the fireplace need not exceed twenty-six inches. When the copper is about to be placed on the blocks, by swinging, or otherwise, three feet of the bottom of the copper should be on one side from the centre of the furnace, and but two feet on the other; I would have but one flue or entrance for the fire to round this copper, which flue should be placed on the three feet side, twenty-four inches long at the mouth; distance of the brick work from the copper, six inches, to narrow to five at the closing; the first closing to be three feet high on the side of the copper; the second closing, to be two feet above that, leaving twenty-one inches clear flue, allowing three inches for the thickness of the brick and mortar; the throat of the first flue, leading into the second; twenty-four inches distance of upper flue from the copper, five inches closing into four and a half inches at top. A short distance above the top of your copper should be placed an iron register to regulate the fire, so contrived as to be handily worked backward and forward by the brewer, or the man tending the fire, as circumstances may direct. The furnace door should be in two parts, one to hang on each side of the frame, and so lap over a small round hole, with a sliding shut to it, should be fixed in one of these doors, to admit the iron slicer to stir the fire. The clear of the furnace frame need not exceed sixteen inches high, by eighteen inches wide. A copper so set and proportioned, by being kept close covered at top, might be expected to boil cold water in one hour and fifteen minutes, perhaps in one hour, and that with a great saving of fuel compared with the same sized copper set in the ordinary way. _Pumps, the best and most economical construction, also the most effectual, and least liable to fail or get out of order; how best treated in cold weather to prevent freezing, or when frozen to remove the inconvenience._ Freezing often retards the brewer's operations, and gives him considerable trouble and delay. To obviate these inconveniences, I would recommend having the rod of wood, instead of iron, so long as to work in a brass chamber, two feet above the lower box; if the pump be long, the rod may be made with joints of iron, and keys properly made, so as to have it in two, three, or four pieces, capable of being taken asunder; suppose the diameter of your chamber to be six inches, I would have the diameter of the rod five inches, which, being so much lighter than the column of water it displaces, will make the stroke comparatively light and easy to the horse, and not near so great a strain on the pump, delivering as much water or wort, it is expected, as will be found necessary for all the purposes of a brewery. But should it so happen, that any deficiency is found in the quantity of water and wort so delivered, it is only necessary to reduce the diameter of the wooden rod, from one quarter to half an inch more, and this will proportionably augment the quantity of water and wort delivered at each stroke. The water pumps, which in winter are exposed to the effects of the external air, should have a casing round them of boards from the level of the ground to half their height above it, which casing should be stuffed with dry hay, straw, or shavings, and well rammed; this casing should be water-tight round the pump, at the top, and a cock placed over it on one side of the pump, to let off the standing water; then stuff the mouth of the pump with hay or straw, and so treated the remaining water in the pump will never freeze in the coldest winter. But where these precautions have not been taken, and the charge in your pump becomes frozen, and you wish to clear it, get one quart of bay salt, throw it into your pump, stop the mouth of it at the top, and in the course of a few hours the salt will have dissolved the ice in your pump, and you may go to work; this is much more effectual and less troublesome than using hot water, which must be repeated in great quantities before it will produce its effect. _Cleansing Casks._ Trifling and simple as this operation may appear, it is still one that is highly important to the brewer, and requires minute and constant attention. Burning and steaming casks seems to be two most effectual modes of accomplishing this important object. If your casks have been long in use, and thereby contracted any musty or bad smell, the best way is to open them; wash them well out with boiling water; set them to dry, and then fire them, after which, they may be washed out again with hot water, and, when dry, headed for use; every cask after emptying, that is not perfectly sweet, should be treated in this way, particularly when intended for stock or keeping beer. New casks that have never been used, are best prepared by steaming them, and a small boiler, containing from sixty to one hundred gallons will be best suited to this purpose. If you have tin pipes communicating from one cask to another, you can steam four or five at a time, and the work goes on expeditiously. Fresh emptied small beer, and single-ale casks, can be sufficiently cleansed by chaining them; after which, rincing them out with hot water will be found a sufficient cleansing for such casks, as they are generally but a short time on draught. The operation of chaining casks is performed by putting into them, with boiling water, a small iron chain, two or three yards long, and then tossing your cask several times round and round so as to get the chain to rub, and act upon every part of the inside head, &c., this will take off the yest, &c. The smoother and evener all brewers' casks are made on their inside the better, as they are thereby the more easily cleaned. Every brewer should be particular in recommending to his customers carefully to cork up every cask as drawn off--by this simple precaution they will be preserved sweet for months, while the neglect of it will cause them to get foul in a short time, to the great increase of trouble and expense to the brewer before he can sufficiently purify them. It is also a necessary precaution to keep casks, when brought home, from the action of the sun and weather, by placing them under proper sheds; where casks are supposed to occupy one fifth of the brewer's active capital, they should at all times be carefully looked after. _The following processes are given principally for the use of gentlemen farmers, housekeepers, and others, who may occasionally wish, as well as find their account, in brewing their Mead or Metheglin._ THE PROCESS. For every pipe of mead allow one hundred and sixty-eight pounds of honey. On a small scale, take ten gallons of water, two gallons of honey, with a handful of raced ginger, and two lemons, cut them in slices, and put them, with the honey and ginger, into the water, boil for half an hour, carefully skimming all the time; use a strong ferment, and attenuate high, not under seventy-eight; in the boiling add two ounces of hops to the above ten gallons of water and two gallons of honey. In about three weeks, or one month, after cleansing and working off, this mead will be fit to bottle. This liquor, when thus made, is wholesome and pleasant, and little, if any, inferior to the best white wines. It is particularly grateful in summer, when drank mixed with water. _Ginger Wine._ Take sixteen quarts of water, boil it, add one pound of bruised ginger, infuse it in the water for forty-eight hours, placed in a cask in some warm situation; after which time strain off this liquor, add to it eight pounds of lump sugar, seven quarts of brandy, the juice of twelve lemons, and the rinds of as many Seville oranges; cut them, steep the fruit, and the rinds of the oranges, for twelve hours in the brandy, strain your brandy, add it to your other ingredients, bung up your cask, and in three or four weeks it will be fine; if it should not, a little dissolved isinglass will soon make it so. _Currant Wine._ Take five gallons of currant juice, and put it into a ten gallon cask, with twenty pounds of Havanna, or lump sugar, fill the cask with water, let it ferment, with the bung out, for some days; as it wastes fill up with water; when done working, bung down; and in two or three months after it will be fit for use: two quarts of French brandy added, after the fermentation ceases, would improve the liquor, and communicate to it a preserving quality. Wine may be made from strawberries, raspberries, and cherries in the same way. _Yest, how prepared, so as to preserve sweet and good in any climate._ This operation, I apprehend, however simple it may appear, will have very important consequences, whether we consider it as a medicine (and in putrid fevers there is, perhaps, no better known) or a ferment. It will be well worth the attention of the physician, the brewer, the distiller, the merchant, and the housekeeper, whether resident in the temperate, or in the torrid zone. Mr. Felton Mathew, merchant in London, obtained a patent for the above-mentioned object, which may be found in the Repertory of Arts, vol. V. page 73. Mr. Mathew used a press with a lever, the bottom made with stout deal or oak timber, fit for the purpose, raised with strong feet a convenient distance from the ground, so as to admit the beer to run off into whatever is prepared to receive it; into the back of it is let a strong piece of timber, or any other fit material, to secure one end of the lever, the top of which should work on an iron bolt or pin; when the lever is thus prepared, get your yest into hair-cloth bags, or, if not conveniently had, into coarse canvas bags; when filled, tie them securely at the mouth, and place one bag at a time in a trough of a proper size with a false bottom full of holes, on this bottom should be placed an oblong perforated shape, about the form of a brick mould; in this oblong shape or box, without either bottom or top, is placed the bag containing the yest, on which the press is let down, and gradually forced, as the beer exudes, or gradually runs off; when no more liquid runs from the shape, the press is taken off, and the bag opened, its contents taken out, which will crumble to pieces; in this state it should be thinly spread on canvass, previously stretched in frames, which will permit the heated air of the kiln to pass through it in all directions, and thus gradually finish the process to perfect dryness, which will be completely effected by ninety degrees of heat: at the commencement of the drying, it would be proper to pass the edge of a board over each frame, in order to reduce the lumps of yest, and thereby make them as small as possible. When completely dry, put it into tight casks or bottles so as to exclude air and moisture: thus secured, it will preserve good as long as wanted in any climate, and be found a valuable article of domestic economy, as well as medicine. When to be used, the necessary quantity should be dissolved in a little warm water, at the temperature of from eighty to ninety degrees of heat, with the addition of a proportionate quantity of sugar; the addition of sugar is only recommended when used to raise bread, but not when given as medicine; in the opinions of several intelligent men, this is considered the simplest and most effectual method of preserving yest, and, as such, is hereby strongly recommended. _To make a substitute for Brewer's Yest._ Take six pounds of ground malt, and three gallons of boiling water, mash them together well, cover the mixture, and let it stand three hours, then draw off the liquor, and put two pounds of brown sugar to each gallon, stirring it well till the sugar is dissolved, then put it in a cask just large enough to contain it, covering the bung hole with brown paper; keep this cask in a temperature of ninety-eight degrees. Prepare the same quantity of malt and boiling water as before, but without sugar, then mix all together, and add one quart of yest; let your cask stand open for forty-eight hours, and it will be fit for use. The quart of yest should not be added to these two extracts at a higher heat than eighty degrees. _Another method to make twenty-six gallons of the substitute._ Put twenty-six ounces of hops to as many gallons of water, boil it for two hours, or until you reduce the liquor to sixteen gallons; add malt and sugar in the proportion before mentioned, and mash your malt at the heat of one hundred and ninety degrees; let it stand two hours and a half, then strain it off, and add to the malt ten gallons more of water at the same degree of heat, and mash a second time; let it stand two hours, then strain it off as before; when your first mash is blood heat, or ninety-eight, put to it one gallon of the preceding substitute, mix it well, and let it stand ten hours; then take the produce of the second mash, and add it, at ninety-eight, to the rest, mix it well, and let it stand six hours, it will be then fit for use in the same manner, and for the same purposes as brewer's yest is applied; the advantages alleged in favour of this method are, that it will keep sweet and good longer than brewer's yest, and in any reason or temperature be fit for use. _Brewer's Yest._ May be generated in the following way: Take one pound of leaven, made with wheaten flour, such as the French generally use to raise their bread, dilute the pound of leaven with water or wort, the latter to choose at ninety degrees of heat, add it to your wort at the heat of sixty-five, supposing your barrel to be filled with wort at this heat; then add your leaven, diluted as mentioned, until your cask be full; to effect which, with less waste and more certainty, it may be better to put into your barrel the diluted leaven first, then fill up with wort at the temperature mentioned; after a day or two the beer will begin to work out yest, and will serve as a ferment for another brewing; thus, after three or four brewings, your yest will become so improved that it will be nearly equal to any brewer's yest, and the experiment in certain situations is well worth trying, when a proper ferment is wanted and cannot be otherwise procured. _Process for making and preparing Claret Wine for shipping; without which preparation such wines are considered unfit for exportation, being in its natural state about the strength of our common Cider._ Claret wine, before the French revolution, was the staple article of export from the great commercial City of Bordeaux, to every part of Europe. And, it may be presumed, will soon again reassume its wanted importance. The vintage generally begins, for making this sort of wine, about the middle or latter end of September, and is generally finished in all the month of October. The mode by which the juice is expressed from the grape, is by the workmen trampling them with their bare feet in a large reservoir or cooler, (not the cleanest operation in the world,) which has an inclination to the point where the spout or spouts are placed for taking off the expressed juice, which is conveyed to large open vats, that are thus filled with this juice to within ten or twelve inches of the upper edge; this space is left to make room for the fermentation, which spontaneously takes place in this liquor. After the first fermentation is over, and the wine begins to purify itself, which is ascertained by means of a small cock placed in the side of the vat, and takes place generally by the middle of February, or beginning of March, in the following year; it is then racked off into hogsheads, carefully cleansed, and a match of sulphur burned in each cask before filling; when thus racked off, it is bunged up, and immediately bought up by brokers for the Bordeaux merchants, and here it is made to undergo the second or finishing fermentation, in the following manner: It may be proper here to remark, that claret wine is generally divided into three growths, first, second, and third; the first growths, namely, Latour, Lafeet, and Chateaux Margo, are uniformly rented for a term of years, at a given price, to English merchants, through whom, or their agents _only_ is there a possibility of procuring any portion of this wine. The second growths are shipped to the different markets of Europe, North and South America; and the third growth principally to Holland and Hamburgh. In order to strengthen the natural body of claret wine, and to render it capable of bearing the transition of the sea, the first and second growths are allowed from ten to fifteen gallons of good Alicant wine to every hogshead, with one quart of stum.[8] The casks are then filled up and bunged down. They are then ranged three tier high from one end of the cellar to the other, each tier about eighteen inches, with two stanchions of stout pine plank, firmly placed between the heads of each hogshead, from one end of the cellar to the other, until they have reached, and are supported by, the end walls of the building. This precaution is necessary to guard against the force of fermentation, which is often so strong as to burst out the heads of the hogsheads, notwithstanding the precautions taken to secure them in the situation during the summer heats. The wine cooper, who has the charge of these wines, regularly visits them twice a day, morning and evening, in order to see the condition of the casks, and when he finds the fermentation too strong, he gives vent, and thus prevents the bursting of the casks. The third, or inferior growth, is exactly treated in same way, with the single exception of having Benicarlo wine substituted for Alicant in preparing them for their second fermentation, as cheaper and better suited to their quality; both these wines are of Spanish growth, and brought to Bordeaux by the canal of Languedoc: they are naturally of a much stronger body than native claret. Thus mixed and fermented, the claret becomes fortified, and rendered capable of bearing the transition of seas and climates. About the latter end of September, or beginning of October, the fermentation of these wines begins to slacken, and they gradually become fine; in this state they are racked off into fresh hogsheads carefully cleansed, and a match of sulphur burned in each before filling. After this operation, they are suffered to remain undisturbed (save that they are occasionally ullaged,) till about to be shipped, when they are racked off a second time, and fined down with the white of ten eggs to each hogshead; these whites are well beat up together with a small handful of white salt; after this fining, when rested, the hogsheads are filled up again with pure wine, and then carefully bunged down with wooden bungs, surrounded with clean linen to prevent leaking; in this state the wines are immediately shipped. Here it may be proper to state, that the lees that remain on the different hogsheads that have been racked off, are collected and put into pipes of one hundred and forty, or one hundred and fifty gallons each, and this lee wine, as it is termed, is fined down again with a proportionate number of eggs and salt. After which, it is generally shipped off as third growth, or used at table mixed with water. If at any time hereafter the method herein given of making and preparing claret wine for shipping, as practised in Bordeaux and its neighbourhood, should be applied to the red wines of this country, particularly those of Kaskaskias; it may be proper here to give a description of the mode in which these wines are racked, which will be found simple, effectual, and expeditious; I mean for the lower or ground tiers. The upper, or more elevated ones, rack themselves, without coercion of any kind. When you are about to rack a hogshead of wine upon the ground tier, you place your empty hogshead close to the full one, in which you then put your brass racking cock; on the nozzle of which cock you tie on a leather hose, which is generally from three to four feet long; on the other end of this hose is a brass pipe, the size of the tap hole, with a projecting shoulder towards the hose to facilitate knocking in this pipe into the empty hogshead, which is then removed a sufficient distance from the full hogshead in order to stretch the hose, now communicating with both. The cock is then turned, and the wine soon finds its level in the empty hogshead; then a large sized bellows, with an angular nozzle, and sharp iron feet towards the handle, which feet are forced down into the hoops of the cask on which it rests, in order to keep this bellows stationary, whilst the nozzle is hammered in tight at the bung hole of the racking hogshead; the bellows is then worked by one man, and in about five minutes the racking of the hogshead is completed. The pressure of the air introduced into the hogshead, by the bellows, acts so forcibly on the surface of the liquor, that it requires but a few minutes to finish the operation; when the cock is stopped, the hose taken off, and a new operation commences. This mode may possibly, in some cases, be advantageously applied to racking off beer, ale, and cider. [8] Stum is a certain quantity of white wine, strongly impregnated with sulphur. The mode of preparing it is as follows: A hogshead half filled with good white wine, or what is termed in French _vin de grave_; from fifteen to twenty long matches of sulphur are successively burned to this hogshead, with the bunghole closed. After this operation, the white wine becomes so impregnated with sulphur, that it has acquired all its taste and flavour, and is thus used as a ferment. _Brewing Company._ It is obvious to very slight observation, that the day is not distant when the brewing trade in this country will, as in England, become an object of great national importance, highly deserving the protection and encouragement of our general government, by freeing its produce from all duty, and thereby affording further inducements to the speculating and enterprising capitalists of this country to embark their funds in a trade that, above all others, is the best calculated to make them a sure and profitable return. In addition to the pleasing consideration that they are thereby combating and putting down the greatest immorality our country is chargeable with, namely, the too great use of ardent spirits, substituting in their place a wholesome and invigorating beverage. The person, therefore, whoever he may be, who contributes his money, or his talents, to this useful and moral purpose, deserves to rank high among the best friends of his country. Under these impressions it is that I beg leave to recommend to my fellow citizens the immediate establishment of a brewing company, with a capital of from thirty to forty thousand dollars, to be subscribed for in shares the most likely to be made up. With either of these sums a handsome beginning could be made, and the profits would in a few years encourage and justify enlargement to any prudent extent that could be reasonably wished for or required. In proof of the correctness of this opinion, I will beg leave to state a fact that has happened in my own time. When the mercantile house of Beamish & Crawford, of Cork, erected a porter brewery in that city, about twenty-five years ago, that establishment was the first of the kind in that town, and then stood alone, and notwithstanding that many large and rich ones in the same business have since been added, the original company have so progressed in fame and fortune, as to be now considered one of the first-rate breweries in Europe; and by the improved quality of their porter have, in a great degree, excluded the English from the West India market, their porter getting the preference there, as well as in Bristol and Liverpool, to which places large quantities are annually sent by that company. How much stronger inducements have we to form similar establishments in this country, where our excise on brewery produce bears no sort of proportion with that paid in England, and does not here exceed five per cent. on brewery sales. This being a war tax, it may be presumed it will not continue long. Our capacity to raise barley and hops, in as high perfection as in any part of Europe, is acknowledged; all then that is wanting is encouragement; afford this to our farmers, and they will soon convince you that no assertion is better founded. If so, the sooner a company of this description is formed the better for those who may be concerned; and for this plain reason, that notwithstanding the enormous excise chargeable on the raw materials and produce of the brewery in England, large fortunes have been, and are daily accumulating in that country by the judicious exercise of the brewing trade, as will appear by the following statement of the quantity of porter alone (beside other malt liquors) brewed by the twelve first breweries in London, in one year, ending 5th of July, 1810. _Barrels of Porter._ Barclay, Perkins & Co. 235,053 Read, Mecar & Co. 211,009 Trueman & Hanbury. 144,990 Felix, Calvert & Co. 133,493 Whitebread & Co. 110,939 Amery, Meux & Co. 93,660 Combe & Co. 85,150 Brown & Perry. 84,475 Godwin, Skinner & Co. 74,223 Elliot & Co. 57,851 Taylor. 54,510 Cloyer & Co. 41,590 --------- Total quantity of Barrels of Porter, 1,326,943 NOTICE. The author informs those persons who may feel disposed to engage in the brewing and malting trades, that he can furnish them with ground plans, and sections of elevation, both of breweries and malt houses, on different scales, whether intended to be erected together, or separately, as will be found to unite, economy, convenience, and effect, joined to a considerable saving to those who are not themselves judges of such erections, or how they should be disposed. An experience of twenty-five years in both businesses, accompanied by a diligent and attentive practice, justifies these assertions. His terms will be found reasonable, and all letters (post paid) addressed to Joseph Coppinger, 193 Duane-street, New-York, will receive attention. A few copies of this work may be had by applying as above; but any number may be had at 45 John-street. TANNING. The following is the French mode of tanning all kinds of leather in a short time, highly important to the manufacturers of leather in this country, as it points out a secure and profitable mode of turning their capital twelve or thirteen times in a year, instead of once. _Washing Hides._ The best method of washing hides is to stretch them in a frame, and place them, thus stretched, in running water. If running water cannot be conveniently had, still water can be made to answer by frequent stirrings and agitations; the remainder of the operation of cleansing is performed as in the common way. _On taking off the Hair._ Begin by shaking some lime in a pit, to which put a great quantity of water, then stir this water well, that it may become saturated with the lime, then place your hides in the pit perpendicularly; for this purpose, several wooden poles should be fixed across the pit; to these poles the hides are to be fastened with strings at proper distances, each hide being first cut in two; whilst the hides were thus placed in the lime water, the lime itself, which had deposited on the bottom of the pit, was frequently stirred up to increase the strength of the water, and to make it more operative; the hair thus treated, will, in about eight days, come off the hide with great ease. A shorter and a better method may effect this purpose in two days; that is, to plunge the hides, after being washed and cleaned, into a solution of tan, which (having been already used) contains no longer any of the tanning principle, mixed with a five hundredth, or even a thousandth part of the oil of vitriol, commonly called sulphuric acid; this operation not only takes off the hair, but raises and swells the hide; as, in the old way, is generally effected by barley sourings. However, further swelling and raising is necessary, and the hides should again be plunged in another quantity of spent tan-water mixed with the one thousandth part of the oil of vitriol, and thus steeped a second time; their swelling and raising will be completed in about forty-eight hours; after this operation the hides will acquire a yellow colour, even to the interior part of their substance. To determine if the swelling and raising be sufficiently completed, let one of the corners of the hide be cut, and if it is in a proper state there will not appear any white streak in the middle, but the hide throughout its whole substance will have acquired a yellow colour, and semi-transparent appearance. Mr. S---- is of opinion, that swelling and raising hides is not necessary, and that the hides tanned without this operation are less permeable to water. On tanning on the new principle, as practised by Mr. S----, he places several rows of casks on stillings sufficiently elevated above the ground to place a can or tub under them; these casks were filled with fresh finely ground tan, then a certain quantity of water was poured into the first of them, which water, as it ran through the tan, exhausted and carried off the soluble part, and as fast as it ran into the vessels below, was taken away and poured on the second cask, and so on successively until the solution was sufficiently saturated, and thus it may have been brought to ten or twelve degrees of the arometer for salts. In order to exhaust the tan of the first cask, Mr. S---- continued pouring water on the first cask until it ran off clear; at which time the tan was deprived of its soluble part; these liquors, as it may be easily conceived, were carefully kept for future operations; large wooden vats are considered the best sort of vessels for holding this solution, as well as for making and preparing it; hogsheads, on a small scale, may be made to answer. It is particularly in the use of this solution that Mr. S----'s method consists; the quickness with which the solution acts is truly astonishing, and when we see it, there is cause of surprise in thinking why it was not found out before. As soon as the hides are taken out of the water, impregnated with sulphuric acid, Mr. S---- puts them into a weak solution of tan, in which he leaves them for the space of one or two hours; he afterwards plunges them into other solutions of tan, more or less charged with the tanning principle, in proportion to their strength, so that in the experiments at which we were present, some heavy hides were tanned in six or eight days, others in twenty and twenty-five days. In placing the hides in the solutions, some precautions are necessary; the hides should be suspended on a wheel, or in a frame where they should be stretched, and placed one inch apart, so as to admit the solution freely about them; Mr. S---- recommends cutting off the head and the neck of the hide, and a slip down each side, in which slip the feet and belly part are to be comprehended; and the circumstance which determines Mr. S---- to cut the hide in this manner is, that the feet, and the parts that are near the belly, are more spongy and more easily penetrated by the tan; and as they produce leather of an inferior quality they may be more advantageously tanned separately, than put promiscuously into the solutions of tan with the rest. The remaining part of the hide is to be divided into two or more parts or pieces, so as to be easily placed in the vats or casks. _Drying the Hides._ The hides, when taken out of the solution of tan, must be dried with the usual precautions, that is to say, so slowly, that the skin does not shrink on the flesh side. With respect to thinner hides, for the upper leather of shoes, Mr. S---- begins by washing and taking off the flesh in the manner already described, or, as is done in the common way for strong soal leather; he then takes off the hair by means of clear lime-water; he does not make them undergo the operation of swelling, but puts them immediately into weak solutions of tan, the strength of which he gradually increases, but without ever bringing it to the degree of contraction, which he gives it when it is to be used in tanning thick leather; two, three, or four days, are enough for tanning the thinner kind of leather. Leather which is not sufficiently impregnated with the tanning principle, is generally known by a white speck or streak, which is observable in the middle of its substance. We can affirm that those hides which were tanned in our presence, in a few days, were completely tanned, as the above mentioned white streak was not perceivable; we may also add, that Mr. S----'s method has the advantage of affording the opportunity of observing and examining, from time to time, the progress of the operation; for this purpose nothing more is necessary but to take a slip off the hide out of the vat, and cut off a corner of it, the white streak already spoken of will appear more or less thick, until the tanning is completed; it has been generally supposed, that the tan in the tanpits had no other effect upon the leather than that of hardening and bracing the fibres of the skin, which has been relaxed by the preliminary of tanning. Mr. S----, however, examined the operation more closely, and discovered that there existed in the tan a principle which was soluble in water, by which the tanning was brought about. That this principle afterwards became fixed in the leather in consequence of a particular combination between the said principle and the skin; and this combination produced a substance that was not soluble in water; all this has been demonstrated by Mr. S----, in the most evident manner. It is well known that if leather, which has not been tanned, is boiled in water, it is in a short time almost entirely dissolved therein. This solution, by being concentrated, produces a jelly, or size, which, by farther evaporation, and being dried in the air, becomes what is called glue. Mr. S---- having, in the course of his experiments, examined the effects of a solution of tan upon a solution of glue, observed that they were hardly mixed together before a white felamentous precipitate took place, owing to a combination of the glue with the tanning principle contained in the solution of tan. This precipitate is insoluble in water, either hot or cold, and acquires colour by being exposed to the light. The foregoing experiment furnishes a true explanation of the process of tanning; for it will easily be conceived that the solution of tan acts upon the hides (from which glue is produced) in the same manner as it acts upon glue; this is what really happens in common tanpits, and Mr. S----'s new method, in which the solution of tan gradually penetrates the hides, and as it penetrates combines with it, producing a gradual change of colour that is very observable, till at last the colour of the hide is changed throughout, and it acquires a compact texture and marbled appearance, like that of a nutmeg: by this it plainly appears, that a precipitation also takes place in the action of tanning, although the hide is not dissolved, but merely swelled so as to enable the solution to penetrate it more easily. The property which animal jelly, or glue, possesses, of being precipitated by a solution of the tanning principle, furnishes a means of discovering what substances may be useful in tanning: nothing more is necessary than to make a solution or infusion of the vegetable substance supposed proper for that purpose, and that upon being mixed with a solution of glue, will show by the greater or less quantity of precipitate produced, what probability there is that such substance might be advantageously employed in tanning. _Another Remark._ Lime-water also offers an excellent means of discovering such substances. If lime-water be added to a solution of tan, the mixture instantly produces a copious precipitate; and if a sufficient quantity of lime-water be added to neutralize the whole of the tanning principle, then the supernatant liquor, although still possessing colour, will not form any precipitate with glue; I mean in solution. In like manner the liquor separated from a precipitation, caused by the mixture of a solution of tan with one of glue, will not produce any precipitate with lime-water, if, during the precipitation, the tanning principle has been completely neutralized. This shows evidently that Doctor M'Bride's method of exhausting the tan by means of lime-water is defective, and that by so doing a loss of the tanning principle takes place, in proportion to the quantity of it contained or combined with the lime dissolved in the lime-water. _Another Remark._ As in summer the solution of tan is disposed to run into the vinous fermentation, and, of course, from that into the acetous, and have its principal changed, no more of the solution of tan should be prepared in the summer season than is wanted for immediate use. In winter, this precaution in not necessary, as in that season it will keep, and may be then prepared for exportation to any part of Europe and thus converted into a profitable article of commerce. _A table showing the time different hides took to be completed, in the operations of preparing and tanning._ Ten ox hides, taken the 17th of August, were completely tanned by the 6th of September, in all, twenty days. Washing the hides, 2 days. Taking off the hair, 5 do. Raising or swelling, 5 do. Second washing, 2 do. Tanning, (properly so called,) 6 do. --------- 20 days. Ten ox hides, taken the 19th of July, were tanned the 9th of August, making twenty-one days. Washing, 2 days. Taking off the hair, 10 do. Swelling, 1 do. Tanning, 8 do. --------- 21 days. One ox hide, taken the 3d of September, was tanned the 2d of October, making twenty-nine days. Washing, 1 day. Taking off the hair and swelling, 3 do. Tanning, 25 do. --------- 29 days. Another ox hide, taken the 5th of September, was tanned the 3d of October, making twenty-eight days. Washing, 1 day. Taking off the hair and swelling, 2 do. Tanning, 25 do. --------- 28 days. N.B. The tanning solutions made use of to these hides was less strong, and of a cooler temperature than usual, by which the time employed in the tanning operation was prolonged. _Calf Skins._ Sixteen very thick calf skins, taken the 18th of July, were tanned by the 31st of the same month. Washing, 1 day. Taking off the hair, 8 do. Tanning, 4 do. --------- 13 days. --------- Six calf skins, taken the 19th of July, were tanned the 2d of August, making fourteen days. Washing, 2 days. Taking off the hair, 9 do. Tanning, 3 do. --------- 14 days. --------- Six dried calf skins, began the 14th of August, were tanned the 28th of August. Washing, 2 days. Taking off the hair and swelling, 11 do. Tanning, 1 do. --------- 14 days. --------- Six calf skins, began the 20th of August, were finished the 10th of September. Taking off the hair and washing, 20 days. Tanning, (properly so called,) 1 do. --------- 21 days. --------- Three calf skins were brought from another tan-yard, the operation of tanning had been begun upon them, they having been thirteen days in the tanpit, in which it was intended they should have remained eleven months, (which was the usual time allowed such skins in the old way of tanning;) two of these skins were tanned in twenty-four hours, the third was tanned in forty-eight hours. Six other calf skins took thirteen days. Washing and taking off the hair, 6 days. Tanning, 7 do. --------- 13 days. --------- _Three salted Cow Hides_, Began the 14th of August, were finished the 12th of September. Washing and taking off the hair, 20 days. Tanning, 9 do. --------- 29 days. --------- _One fresh Horse Hide_, Began the 30th of August, was finished the 13th of September. Washing, 1 day. Taking off the hair, 6 do. Tanning, 7 do. --------- 14 days. --------- _Another fresh Horse Hide_, Began the 4th of September, was finished the 19th of September. Washing, 1 day. Taking off the hair, 7 do. Tanning, 7 do. --------- 15 days. --------- _Two dried Sheep Skins_, Began the 14th of August, were finished the 12th of September. Washing and taking off the wool, 25 days. Tanning, 4 do. --------- 29 days. --------- _Three Goat Skins_, Began the 16th of August, were finished the 10th of September. Washing and taking off the hair, 23 days. Tanning, 2 do. --------- 25 days. --------- _Five Goat Skins_, Began the 19th of August, were finished the 10th of September. Washing and taking off the hair, 20 days. Tanning, 2 do. --------- 22 days. --------- THE END	61,676	common-pile/project_gutenberg_filtered	20663	project gutenberg	project_gutenberg-dolma-0002.json.gz:1108	https://www.gutenberg.org/ebooks/20663.txt.utf-8
bUt7dWARXur12S9u	Every man his own guide at Niagara Falls without the necessity of inquiry or possibility of mistake, including the sources of Niagara, and all places of interest, both on the American and Canada side, embellished with views of the falls and suspension bridge, by the best artists, and a large map of Niagara River, by the author : also a full description of the several routes from the falls to Boston, Saratoga Springs, via Lake Ontario, Lake Champlain, Albany, New York, etc. / F.H. Johnson.	The Inttituta has attamptad to obtain tha baat original copy availabia for filming. Faaturas of this copy which may ba bibliographically unique, which may alter any of the images in the reproduction, or which may significantly change the usual method of filming, are checked below. distortion le long de la marge intirieure Blank leaves added during restoration may appear within the text. 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Lorsque le document esf: trop grand pour Atre reprodult en un seul clichA, 11 est film* A partir de I'angle supArieur gauche, de gauche A droite. et de haut en bas, en prenant le nombre d'images nAcessaire. Les diagrammes suivants illustrent la mAthode. TO THE VISITOR. Tliifi is the only original, correct and reliable irork in Biarket The author, for several years, has been personally and familiarly acquuinted with all the points of interest of Uiia "world's wonder/' and great pains hare been taken to make this work in every respect correct, and worthy the attention of the tourist The different routes ind places are so arranged and minutely described, thai the stranger cannot bo misled or hesitate. These pagei ■re given to the public, with the belief tliat something of the kind is needed, inasmuch as works written by casual observers, are either unnecessarily oblix upon some points, or not sufficiently clear and explicit upon others, to meet the wishes of the traveling' public This diffi* sulty, it is oclieved, is entirely obyia.,,d in the following CHAPTER I. If tlie visitor stops at tlio Cataract House, and wishes in tlie first place to view the scenery on Goat Island, take the first left hand street, two minutes' walk Lrinojs him to the bridijc that loads to the island. If at the Falls Hotel, pass the Buflido and Niagara Falls railroad depot, incline to the left, tho bndge leading over the rapids is in sight, and but a few rods before you. If at the St. Lawrence Hotel, or the Niagara House, pass up Main, take the first right hand street, pass the depot, incline as above to tlie left, the bridge is just before you. Leading to the toll-gate, on Bath Island, is about fifty rods above the Falls. It is an object of interest ; and the inquiry is not unfrequently made, how v»as EVERY MAN HIS OWN GUIDE. it eynv constructed over sucli a tremendous rapid. The tir."t bridge was thrown across this angry stream in 1817, near the grist-mill on Iris or Goat Island, with much hazard of life, and great expense. It \ras caiTied away by tlie ice the ensuing spring. In 1818, another was constructed ^\here Bath IsUmd bridge now stands, by the Hon. Augustjus Porter, and General P. 13. Porter, broth oi-s, the proprietors of the island. A suitable pier was built at the water's edge; long timbers were projected over this abutment the distance they wished to sink the next pier, loaded on the end next to the shore with stone, to prevent moving ; legs were framed through the ends of the projecting timbers, resting upon the locky bottom, thus forming temporary piers until more substantial ones could be built. Visitors all pass this bridge on to Goat Island. It is perfectly safe ; car« riages and heavy loaded teams cross it almost every hour in the day. The next thing that atb-acts the attention of the visitor, as he passes on his route to Goat Island, is the rapids. These are grand and impressive ; thousands, in the summer season, particularly when the sky is clear, stand upon this bridge, and gaze upon the angry flood, as it roi^ues past them, in all its wild of awe and indescribable grandeur. From tlie head of Goat Island, to the grand cataract, a distance of three-quarters of a mile, the river falls fifty-one feet. It increases in velocity from seven to fifteen miles per hour, before it makes the final plunge. This island is t© the right of the bridge, within a few rods of the American Fall. A man by the name of Chapin, while working on this bridge, was thrown into the stream, and earned by the force of the current on to this island. A Mi'. Joel R. Robinson rescued him with a skiff, and at this time, both are hving in our village. Hundreds of ladies and gentlemen witnessed this bold and daring adventure, which few, at so much hazard of life, would have the nerve to attempt. Stands on Bath Island. An excellent batliino: house, of warm and plunging baths, is kept in fine order, for the accommodation of visitoi-s ; open at all hours of the day, until eleven o'clock at night. By registering your names at the gate, and paying twenty-five cents, entitles you to all the privileges of stay. ILmo is constantly kept a largo as,sortment of In:lian work, and other curiosities. The sm.'ill islands to the left of the toll-gate, are called Ship and Big Islands, taking their names somewhat from their shape. The large huilding to the right, is a paper mill, said to be the largest and most exteusivt in the state. The next point of interest after passing a small bridge, is Iris or Goat Island. The In<lian Emjioriimi on your left, ia the only house inhabited on the island. A large assoiimeut of Indian work ia kept constantly on hand and for sale; a delightful place to rest. Ice cream and strawberries furnished in their season. Here are three ways th© left leads to the bead of Goat Islard, the middle one acrnsa the island to thejapida, about sixty rods above the Horse Shoe Fall. But most of the visitors do, and we v.'iP,) if you please, take to the right, from tha fact that we get the less impressive view of the FidU at fii-st, and the most grand and imposing last; which, in the opinion of the author, gives the mind more time to appreciate the magnificent grandeur, and awful sublimity of these mighty works. Kighty rods brings us to the foot of the island. The fi rst small sheet of water nearest you, is the Center Fall, or Cave of the Winds; it is about half way between the iVmerican, and the Horse Shoe Fall, 1 • is cave is between Goat and Luna Island. It is seen to the best advantage from below, if tlie wind is blowing down the river, or from the Ar.erican shore; you can stand with perfect safety upon a large^ flat rock, within a few feet of the falling sheet, without inconvenience, or getting the least wet In the afternoon, when the sun shines, there is always a splendid aqd beautiful rainbow, between the sheel of water and the rock, within a few feet of you, and this is the only place on the globe, as far as the author can leani, from history and from travelers, where a rainbow, an entire circle Uke a ring, can be seen. Two and sometimes three have been seen at once. Nothing, in the opinion of the writer, can be more grand and imposing than this view. It is one of the most astounding scenes on the American side. Width of the cave is one hundred feet, diameter sixty, heighth one hundred. The enterprising proprietor has erected convenient seats, with good, substantial railing, which leads you into this cava^ between the sheet of water and the rock, on to a platform beyond. It is much visited both by ladies and gentlemen, not only for the novelty of one of the grandest shower baths on earth, but the scenery is perfectlf ^ iodescribable These profiles are at tlie foot of Goat IsWd. Id looking across tlie first sheet of water, directly under the second, the lowest point of rock that can be seen is a side view of three profiles, one directly above the other. They appear about two feet long, and much resemble the work of human hands ; the middle one is generally considered by strangers to be the most distinct. , . Luna, a Latin term meaning moon. It is a small island containing about thiec-fourtlis of an acre, to the right of Goat Island, reached by a foot-bridge. It is called Luna Island, not because it resembles the moon, but from the circumstance of a lunar bow being seen from this place more advantageously than from any other point. If the visitor's nervea are pretty steady, he can stand within one foot of the Falls, and see the angry stream, dashing in all its wildest fury upon the large rocks below, impatient to try its power in making this fearful leap. The sheet of water to the right is the American Fall ; to the left, the Center Fall or Cave of the Winds. It baa often been remarked by strangers that this island trembles, which is undoubtedly true, but the impressions are somdwhdt heightened &om nervona temperament. 8AM PATCH 8 LEAP. Tt wfw ftt tliis point, after wo pnas a small footbridge about twenty-fivo feet above the Falls, thjit young MLss Antoinette De Forest of Buffalo, aged eight years, by some unaccountable casualty fell into the river, and Charles Addington, aged twenty-two, jumped in to save her, and they both went over the Falls together, June 21st, 1849. The body of the girl was found much mutilated, the next day,, and that of the young man floated four or five days afterward, when it was recovered and buried in the village buiying ground. This was one of the most afflictive scenes that has occurred witliin our recollection. Return by the same way to Goat Island. After resting a few moments, pass up the river to a sign on a tree, Biddle Stairs. Is on the west side of Goat Island, near Biddle Stairs. This celebrated pereon made two successfid leaps in the year 1829, ninety-seven feet perpendicular, into the river below. Question by the visitor: How was this done ? A ladder was raised, the bottom roasting on the edge of the river, the top inclining over it. Stayed by ropes to the trees on the bank, on the top of which was a small platform, he Btood gazing upon the multitude in Canada. The carriage-road on the opposite side of the river, and every other point where there was the least prospect XVIRT HAK III8 OWN OCIDI. of seeing, waa filled with ladies and gentlemen, attracted to the place by a man going to jump over the FttlLj. "One thing," said he, "can be done as well as another," bowod to the audience, stepped off the platform, and went down feet foremost. Q. How much did he get for the job ? A. This is not known, as it was a project got up by the tavernkeepers to attract attention; whatever they gave him, they kept to themselves. Q. How dec^p is the river where he went in. A. About fifty feet. Q. How deep did he go down ? A. It is difficult tc» answer this question correctly — probably not more than fifteen or twenty feet. Water is exceedingly buoyant; when the accelerated force of the jump was spent, he would instantly rise. Q. How long did he remain under water. A. Some said, he wjis gone for good, others affirmed it was five minutes : but a gentleman holding his watch informed us, it was just half a minute before he rose. Q. What became of the foolhardy fellow? A. He made a jump at Rochester, Genesee Falls, the same year, which was his last His body was never found. Are on the west side of Goat Island, no^r the foot They were erected by Nicholas Biddle, late president of the United States Bank. "Make us something," said he to the workmen, "to descend PROSPECT TOWER. and ftC'O. ^vhat is below." Those stairs arc spiral on \liii inside, tirrnly socurod by heavy iron bolts fasU^ned into thu solid rock, and ore, we beliovo, peifeclly safe. At the foot are two paths leading in opposite directions; the one up the river leads toward the Horse Shoe Fall, but the path is so much obstructed by rocks which have fallen, and the bank is so steep, tlijit it is extremely difficult to got within thirty rodi of the Horse Shoo Fall But the best view, decidedly, is to turn down the river a few rods, and the Center Fall or Cave of tlie Winds bursts upon the astonished sight, with all its terrific grandeur. The impending rocks hanging over you, sometimes fill tlio visitor with alarm lest they might fall, but they seldom fall in the summer season, and no accident has occurred since the year 1829. For number of steps see local distincos, page 28 Ascending these fiUiirs on his return, (for there is no other way,) if he travels very slowly, he will avoid much fatigue. On his return to Goat Island, pass up the river about sixty rods to a small house built by the proprietor of the island, for the purpose of rest. Descend the bank, cross a small bridge to the tower. ThiiJ is called Prospect Tower. This tower is on the west side of Ooat Island, within three rods of the Falls ; forty-five feet high, and two hundred feet above the river below, surrounded near the top by a portico and an iron railing. Visitors of a nervous temperament, and especially old people, when stepping out upon this piazza, not unfrequently feel a kind of giddiLess or tremor; but in looking up or around u\|x>n the green fohage, the nerves generally b«oome tranquil. We a^u then bei* ter prepared to appreciate the overwhelming grandeur of this magnificent scene. This view, in the opinion of the author, of the width of the river, the rapids, the Hcrse Shoe Fall and the angry, boiling deep below, is not surpassed by any on the American side. been called the river of milk. This is the entire circle from the American to the Canadian side of the river. Its width by calcalation ij» one hundred and forty-four rods. It derived its name from its shape, but it must have altered much since it was first named, as large masses of rock \t the neighborhood of the Horse Shoe, fall every yea* Professor Lyell says, fifteen hundred millions of cubic feet pass over the Falls every minute. Dr. Dwight says, one hundred millions two hundred thousand tons pass over the Falls every hour. Judge De Vaux, in his Traveler's Own Book, says, five thousand eighty-four miUions eighty-nine thousana eight hundred fifty-three barrels descend in twentyfour hours; two hundred eleven millions eight hun* dred thirty-six thousand eight hundred fifty-three every hour ; three millions five hundred thirty thou<jand six hundred fourteen every minute ; fifty-eight thousand three hundred forty-three every second. ^'I should think," says one, "that the river would exhaust itself." True, when the npper lakes run dry, Niagara will be no more. It is estimated, by Professor Lyell and others, to be twenty feet in the center, or where the water looks so green. There is, however, a better data^ ascertain tuis fact, than all the calculations, however learned. The ship Detroit being condemned on the lake, was bought by a company, loaded with a hvt bufialo, bear, doer, and other animals^ was sent over the Falls in the year 1829. She v.is knocked to pieces in the rapids, except about half of her hull, which was filled with water. It drew eighteen feet, and passed over the point of the Horse JSlu>e, clear, without touching. Hundreds saw her make this fearful plunge, and I have no doubt in my own mind that the estimates are con-ect. Tiiis, then, gives a solid column of water on the top of the rock, twenty feet, or as deep as an ordinary welL This is a small island just above the Hoi'se Shoe Fall. It has never been approached by man, and perhaps never will while Niagara rolls, unless a suspension bridge, or some other means are devised. It took its name from the quantity of gulls that, late in the fall and early in the spring, light upon it, and some think hatch their young there; at ail events they are not dis' j-bed, and are The visitor, after spending what time he Tvnshes on Prospect Tower, will return to the bank. If he wishes to reach his hotel by the nearest route, without going round by the head of the island, take a small path dinocUy back of the building fronting Prospect Tower. This is a pleasant walk leading to THRES SISTBRS. the bridge, and shortens the distance more than one-half. But we will suppose he wishes to continue his rambles around Goat Island, as there are many objects to excite, and will peculiarly interest him. The best point to get a correct view of the shapo of the Horse Shoe Fall, is about forty rods up tie river, from the point where you ascend the bank from the tower, near A small stone monimient, directly in his path, marked with a cross on the top, set by the^surveyors to ascertain if tlio Falls recede. Let him step to the bank, and he will get one of the best views of the shape of the Horse Shoe there is, on either side of the river. As the visitor passes np the river, he will notice piers filled with stone near the water's edge. These were made by the proprietor of the island, to prevent the bank from washing. The next thing he notices is three small islands near the shore. These are c^-led A man by the name of A. P. Allen, some eight years since, in attempting to cross the river in a skif^ from Chippewa, unfortunately broke one of his oars; but with a skill and coolness never surpassed, he managed to reach the outer island, jumped ashore, while his skiff darted on like an arrow over the Falls. Though saved from immediate death, yet his situation was perilous in the extreme, the hope of rescue was extremely doubtful and starvation was staring him in tlie face. Two niglita and one day he remained upon this lonely spot. lie struck a fire, the smoke wreathed in columns ahove the ti-ee-tops. Great numbei-s of our citizens assembled, and heard his cries for help. At length a rope was thrown across from one island to the other, and by means of a skifi^, the same intrepid Robinson that rescued Chapin, succeeded in bringing him safe to shore. Both ai'e Hving in our village at this time. The bathing place of Francis Abbot is on the west side of Goat Island, the flret perpendicular cascade after leaving Prospect Tower, near the three islands called the Three Sisters. He was learned, gentlemanly and accomplished, pleasing in address, but could not be approached by a stranger; he lived nearly twenty months entirely alone. He was drowned below the ferry, in the year 1831. His body was found at Foil Niagara, fourteen miles below, recognized, brought back and sleeps in our burpng ground. This lonely spot was resorted to by this singular indi>ddual generally at night The thunder's tenific sound, the liglitiiing's blaze mingled with the roar of the catai'act, was the element in which he delighted to breathe. Very Uttle is known of his history. At this point, Navy Island, near the Canada shore o the right, containing three hundred and forty acres, the scene of the McKenzie war in 1837-38, is in plain sight It was occupie by three or four hundred Ameiicans — a heterogeneous mass of all classes, without discipline, or any efficient means to carry on war. Chippewa, on the Canada shore but a short distance below, contained at the time four or five thousand British soldiers. The two governmenta took no active part in this hot-headed enterprise, and it fell by its own weight. Grand Island is to the left on the American side, resembling the main shore, containing seventeen thousand two hundred and forty acres, purchased by M. M. Noah, and aocording to his fancied visions it was to be the future home of all the Jews on the globe. The visitor in turning his eye to the right and left, will readily perceive how this island divides the river, the greater portion rolling to the Canada shore. It would, while passing the bridge, be thought incredible that any person could reach the island before any bridge was built Yet such is the fact; BF> early as 1765, several French officers were conveyed to it by Indians in canoes, carefully dropping down the river, between the dividing waters whore the river for some httle distance is calm, and Peter B. Porter of Black Pock, with jcme other gentlemen, IVXRT Mlir BIS OWN QUIDI. also made a trip to the island in a boat. Thej found but little trouble in descending, but their return was difficult and hazardous.* It was eflfected by shoving the boat with setting pules up the most shallow part of the cun-ent for a half a mile, before making for the shore. Falling into the current, within a mile of the Falls, must b« fatal. Several accidents of this kind have happened, but all, as far as the author can recollect, were hurried on to destruction. It is but a few years since an Indian, partially intoxicated, on attempting to cross the river in a canoe, was drawn into the rapids. Finding all efforts to reach the shore unavailing, he took a good horn of whiskey, lay down in his canoe, passed rapidly over the Falls, plunged into the yawning vortex below and disappeared forever. At this point, the head of Goat Island where we are now standing, it can be more satisfactorily explained, why it was called Goat Island. A man by the name of Stedman, about seventy years since, put some goats upon the island, which remained there nearly two jeai% He reaehed the island and returned the same way iB the Indians and others had done. wlioni it Ivilonfred, Tiothinor defiuite is laiown. It il FU]-)\|)()se(l by some thoy wore the Iroquois. The fol* lowiiii^ lilies were composed by a young hidy from Boston, while seated under the shade of a cedar, '^ tlie lu:'ad of Goat Island, looking over the graves of the wai'iiors, the niigh(y dead, who sluud^er in si leuce here. Indian bones have been exhumed withiw a few years. The once noble, and valiant, and brave, where are they 1 "We will now reiiirn to the hotel. Sixty rods brings us to the former residence of Francis Abbot, the hermit of Niagara. It was an old log-house on the east side of the island, but within a few jeara has been taken down. Here he hved for twenty months entirely alone, as he could not be approached by a stranger; though gentlemanly and accomplished, having seen much of the world, and possessing a mind replete with useful knowledge, yet he held converse with none, except a few confidential fj-iends. A few things w© will pass in review, in reference to this route, before we take a trip to Canada, or leave this enchanting spot forever. Iris or Goat Island contains sixty-nine and a half acres, is a fraction over a mile in circumference, and heavily timbered. Most of the smooth bark trees are marked with initials bearing different date-. "In 1805," saya Judge Porter, "there was a beech tree on the bank near the Horse Shoe Fall, marked travelers are not recollected. No sportsman is allowed to carry a gun on to this island, aa it would endanger the lives of those who are promenading through it. It is called Goiit Island, from the circumstance of a man by the name of Stedman, at a vejy early date, having put some goats upon it. It is a wild, rural and delightful ro treat ; in the hottest days, there is always a refreshing and invigorating breeze from the river. There are three bridges connected with this island and one tower. The visitor will perceive there is an excellent carriage-road entirely round the island, and if he chooses, he can get a good carriage to carry a party Spray, like smoke of a burning mountain, sometimes rises into tlie Lorizon, forming dark, heavy clouds, tinged with the refulgent rays of the rising and setting sun, -wbicli Lave been seen, says Judge Poller, more than one hundred miles. There are two: — One is always seen in the daytime, when the sun shines ; the other at niglit — called the Lunar Bow. The latter is only buhdil once a month, when the moon is at full, sufficiomly high in the heavens, and the sky clear. And ]S'i;igara, as far as the author can learn fjom travelers and from histoiy, is the only place on the gl<jbe, whcrQ An evening view liius a very dillorcnt ellbct upon , tho mind of tho behulJer, than wlion seen in tho daytime. The nioon-beanis pl-'iyiiig upon the agitated uators; tlie s]iray, hi^e tlie 'uoko of a volcano, rising into tlie sky; the ontlless roar of the cataract, mingled with the heart's deepest impressions, give such an indescribable sublimity and grandeur, that hmgunge is but a poor vehicle to convey tho inipresBions we feel. This view is thought, by thousands, to be perfectly uiLSurpassed ; and has no rival in grandeur, sublimity, and interest. Every point of time, however, is different, and has its different etiiact upon the beholder. "When tho sun has rolled onward in his chariot of fire, and thrown his last rays upon ^Niagara, bidding adieu, for tho night, to tho gr.'inJeur of the scene that so much in power resembles himself, tho view is perfectly indescribable. This depends mucli upon the wind, and the state of the atmosphere. Sometimes, every door and window, the least ajar, for a mile in circumference, will tremble — caused by the concussion of the air; and the 'oar may be heard from fifteen to twenty-five miles. At other times our citizens would scarcely know that there were falls in the neighborhoo<L " In a few instances," says Mr. Hooker, the oldest <yuide to the Falls, "they have been heard at Toronto, a distance of forty-four miles." At first sight, strangers are sometimes disappointed ; either their expectations have been raised too high, or the sublimity, grandeur, and magnificence of the scene far surpasses every thing they could possibly Jiave anticipated. The second view is frequently more impressive than the first. The longer the visitor tarries, the morfc ho* enjoys and appreciates; the impression is indelibly cnstamped upon his memory, and for years infixed thore, as with the imprint of a sunbeam. The Falls, if is true, when seen from above, do not appear more than fifty or sixty feet high; but let. the viiiitor go below, if he would get a correct impression of this stupendous work. Beauty Those causes which swell other rivers, have no eCect upon this. It never ris-^s unless the wind has been blowing down Lake Erie in a westerly direction. S. Ware, Esq., who has kept the ferry for seventeen years, says, " one foot on tha top of the Falls, will, by actual measurement, raise it seventeen and a half feet below." This is attributable to the river being pent up in a very narrow pass at the Whirlpool, and cannot find its way out as fast as it accumulates above. From Lake Lrie to Lake Ontario, (36 miles,) 339 feet; from Lake Erie to the head of Goat Island, (22 milea,i 25 feet; from the head of Goat Island 60 the main fall, (half a mile,) 50 feet; perpendicular heigl '. of the American Fall, 164 feet; on the Canada side, 158 feet; from the Falls to the Whirlpool, (2^ miles,) 64 feet; from the Whirlpool lo Lake Ontario, (11 miles,) 25 feet. On tlie morning of the lOtli September, 1841, more thai four hundred ducks were picked up, dead, having gone over the night previous. If fish should take a perpentjcular direction, they might survive. But if they should strike flatwise, it would, in our opinion, kill them as sud.^f^nl -is if they fell on a rock. The usual crossing place is 2 1-2 miles above the Falls; though sail-boats and canoes, when the wind is blowing up the river, have crossed much nearer. It is thought by many, who have visited the Falls at this season, that it far surpasses that of summer. The icicles, in the shape of inverted cones, hanging from the high banks, the dazzling splendor of an effulgent sun darting his fiery beams upon them ; the frozen spray, clothing the trees in its silvery robe; the roar of the ice, as it rushes onward to try the fearful leap ; the ceaseless thunder THE FIRST MAN WHO RAW THE PALLS. 33 of the cataract, the bow of promise, smiHng serenely upon the angry flood; tlie enchained river within its icy embrace, struggling like some monBter of the deep to be free, all combine to render the scene awfully grand and terrific. No language is adequate to give a correct impression; it must be Been before it can be appreciated. The first white man who saw the Falls, as far aa we have any authentic record, was Father Hennepin, Jesuit missionary, sent out from the French among the Indians, as early as the year 1678, 174 years since. His descriptions were visionary, and exceedingly exaggerated. He thought the Falls six or seven hundred feet high, and that four persons could walk abreast under the sheet of water, without any other inconvenience than a slight sprinkling from the spray > But we would not attribute this wild and fanciful description, to a want of candor, or an intention to deceive. The fact probably was, he had no means of measuring its height, and undoubtedly got his account ffom the Indians, which very ikely would be incorrect he sacrificed to the Great Spirit of these \.^wc»a. Whether any reliance can be placed upon the tradition of the Indians or not, it is nevertheless t.rue^ that almost every year has proved fatal to some one. A few instances, only, c&n be mentioned. John York, who is supposed to have gone over the Falls, as pieces of his boat, and part of the loading were picked up below, 28th Nov. 1841. William Kentedy was in the boat with him, and found dead on i. . ^' Island, just above the Rapids. Dr. Hungerford, of West Troy, was killed by a rock falling upon him, between Biddle Stairs and the Cave of the Winds. May 27, 1839. J. H. Thompson, of Philadelphia, was washed oflf of a rock below the Falls, under the great sheet of water, by leaving the guide and venturing too far upon places of danger. August 16, 1844. Miss Martha K. Rugg, from Lancaster, near Boewn, Mass., while picking a flower, fell over the bank, just below Bamett's Museum, (Canada side,) one hundred and fifteen feet. August 23, 1844. She lived about three hours. eAflUALTIlSk vKaUW ladj, of our villiige, attempting to croas the river in a canoe, about a mile above the Falls, was drawn into the current and went over. His body has never been found. June 13, 1847. body has never been found. A gentleman from Buffalo, supposed to be on an excursion of shooting ducks; his boat was drawh into tlie rapids above the Grist Mill — seen by several of our citizens to pass under the Bridge-— heard to exclaim, ^ can I be saved. His boat, with the velocity of lightning, passed on, dashed against a rock nearly opposite the Chair Factory, he was thrown out — went over feet foremost, near the American shore. August 25, 1848. He has neror been found. A Mrs. Miller cat her shawl in pieces^ tied them together, hung it over the Bridge leading to Qoat Island, intending doubtless to impress the belief that she had let herself down into the angry flood, and had gono over the Falls. Very few of our citizen believed it, as there was too muoli pains taken, for the purpose of committing suicide ; it was all a farce, as she was heard from at Syracuse and other places, a few davs after. Some love affair occasioned this wild freak. Her little children were very kindly taken care of by Hon. A. Porter, until lier friends at Detroit could be informed of the occurrence, and they removed to their home. Her father, a very respectable lawyer, died soon afterward, it waa thouo-ht of a broken heart. A gentleman from Troy, X. Y., in the winter of 1852, while passing over the Bridge to the Tower, fell into the river, was instantlv carried to the verfje of ^he precipice, and lodged between two rocks. Mr. Bruster I . Davis rescued him, by throwing some lines in the direction; he had just sufficient strength left to tie them around his body, and they drew him to the Bridge, whence he waa taken to the Falls Hotel. He remained speechless for several horn's, but finally recovered and returned to his home. There are not as many accidents in proportion U the number who visit the Falls, as among our citi zens. Strangers are generally more careful and timid, cautious how they approach places of apparent or real danger, until satisfied of theur perfect safety. Some have a more fool-hardy adventure in ACCIDENTS TO STIlANGERS. Jieir constitutions; "will p.^s into crags and rocLs, ^•here hiinian bcinfj.s never ought to go. Tiiis is not only dangerous, but it is perfectly uncnlled for, as all the -wlldness of tins terrific scene cm bo viewed without running the least risk. It Inis frequently been remarlied to the author both by ladie^s and gontlonien, v»hile standing upon Rome gid'ly point, say an isol.-ited rock, on tlie west side of rro?[>ect To\ve!-, on the very brink of the Falls, "I have a great rr.ind," say thoy, "to give a jump; d») you thiii\' it v/ould hurt me." The reason of t!i:.< disposition doubtless is, they are not accustomed to stand u;u)nsuch afriglilful eminence. There is, unqiiestivuaMy, a determinatiuu of blood to the brail;, vrhieli pro'luws a partial derangement. Some arc of thrit nervous temperament, constitutionally formcvl, that they become dizzy in looking dovrn from abnost any height, thougli at other times thoy iniglit face the cannon's mouth, and hear it thunder, without moving a muscle, yet here they are afraid. These remarks are not made to alarm, or in the least to detract from the interest of the slrano-er'.i visit, but to caution. The author, until recently, for many ye^irs acted as a Guide; ho will relate an incident, as exem])lilying iho above remarks: a young lady was standing upon Table Hock, on the very verge of th(i precipice, the viiud at the time blowing strong from llie Canail.'i slioro; slio appcaiJed amazoil, bcwiklercd, and lust amid tliis overwlielming, enchanting sceno. Madam, said I, arc you not unuecess^irlly ox]>osing youisclf ? AVliilo laying my Land slightly u])on hor shoulder, Oh ! she replied VAith a sniilo, I could juniji ofi' here, and sail away like a balloon, v.itlioul inji'.ry; and with much entreaty, she was ])revailed upon at length to leave this dangerous spot. 'ihe observed afterward to Ler mother, who very pleasantly reprimanded her for this daring freak, I did not feel the least fear, or dread, and was not aware that I was in any danger; " I thought I could fiv." In many other inBtances, I have observed in some strangers the sanw disposition; regardless of fear or danger, or the adrice of friends they often feel disposed, they say, to try the fearful le;i]>; we know these are facts, and leave tlie subject for writers on mental philosophy to enlarge upon, and assign the cause. Thousands, in the summer season, when the t^realher is fair, promenade through the Island a night — It is a delightsome treat. The carriage-road is iSne, the dark forest, in all its native grandeur, ia around them, not a breath moves the surrounding fohage, the moon pouring a flood of mellow light tibough the openingii of tho trees, the Rileuce of death ia only iutuiruiited by Niagar.i's ceaseless roar, riilin<^ the mind with oniolioas of awe, grandeur, and sublimity, ^vhich it is perfecUy impof^dibla to describe. It must bo viewed befuie it can bo appreciated. Can only bo seen about once a month, or when tlic moon is within two or three days previous or after its full. Tlie re;iaon is, there is not light enough to iorm tho Dow. The best points to view tliis grand spectacle are, at the foot of Goat Lslanl, on Luna Island, and Prospect Tower. If tho slxy ia clear, tho wiird right, and the atmosphere favorable, an entire arch c;m bo seen. The author has froqucntly seen a wdiole arch, with three C(_>l')rs very distinct, and wo are inclined to beliovo, as far as wo can learn from travelers, this is tho only place vn tlio iilobo, where a rainbow at niicht, in the Honn of an arch, can bo seen at alJ. It is indescribably gfraud, worthy tho attention of the tourist, and will amply pay liim for a trip to tlio Island, to behold. " Thdu hast told mo right," said a party of Quakers, from Philadelphiji, to tho author, " this sight alone, is suhicient to pay us for a journey to the Falls." The mind takes a wild and sublimo range, but [{£, emotions cannot be 05i)res£>od« If t]i'j visitor is jit llio Cataract House, tako the fiivt left Land street, thoi' turn to tlio right at the old Curiosity Shop. If .".t tlio Falls Hotel, pass the Ihiff'h and Is iai;-;ira Falls railroad de])ot, iiicliuo to the r!':::ht. It' at the St. Lawrence Hotel or the Nian^ara House, pa'i.s up Aln'ri street, pa.-s the depot a.s above, iuil three or l'v,)ur iniiuil.es wtdk Lrlnirs you throuirh a ple^asaiit grove to the Ferry. TliG Ferry Iloure in ^vithin ciL:;ht rods of tho American Fall. Cara lead down tho l;ank to the ^vater's cdg'^, on an inclined plane of thirty-one degrees, ">,vorked by water-power. Distance, tweiitytwo an^l a Iialf rods, or two liundred and ninety rf^}ps. Tlio usual time in descending and crossing tho river to the Cana.da shore, is about ten minutea "This Ferry," says Judge Porter, the proprietor, "has been in operation more than forty year;; >i,A durinn; all that time not a ;;in(;'le life has b^^im Icr-l or a serious ac-cident occurred" any olhor ferry in tlio United St'itcs, Tlio boats vliicli jily back and forth almost every iiioniont in Uio day, wLon soon from tho liigb bank, apiiear, jw tliey danco upon tbo agitated ^vavos, exceedingly diuiimitivc and insecure; yet tiicy ^vill f^afcly carry Lliirty i)Ci'sons. At the foot of tho sUiirs, or "vvliero tho cars stop, if there is httlo or no ^vind, or if it is blowing 'up tho river, let Iiim turn short round to the left IIo can approach ^^ithin a ^k^w fe(.'t of tho American Fall, ■svithout iuconvcnienco from tho FI)ray. It is, in tho opinion of tho Avriter, one of the most gr.'uid and sublime ^•^e^v8 on the American fiide. At no other j)oint do Ave got as correct an impression as to the height of the American Fall The reason is, we ai'o below, nearer the falling sheet, and are looking up. This remark holds good everywhere; if we would get a correct idea of heighl-s, we must be below and look u]). — (Questions by the visitor while crossinix tho river: How hi;"-!! is tlio American Fall? A. One lumdrcd and sixtv-four feet, perpendicular. Q. Do thoy ^o under that fall ? A. Never; an attempt was made a few years since, but it was abandoned as a Ijoj)eless cfl'vjrt. Q. How deep is the river? A. In tho center it averages two hundred fifty feet, fjr a ?,nile up and a^^wn. Q. What is tho cause of this dark, green color! A. This h:us never been satisfactorily expkiii^ed; some think it is in the foliage, but this must be a mij>t-iko; llio snnio nppocnranco is seen in tlio winter as well as in the sinniner. Tlio most jirubuldo rearaon npjH'.'irs to tlio "writer to bo its tlopth, A\o would willingly cxcliannro this o\|»ini(>n f(,)r a Letter, whenever it can bo ukuIo to .'i]ij)tar it is erroneoiist Charges for cro'ssiiig tho ferry, including tlio Gal's, Is cigbtecn (UkI three-* j[U.irtcrs eenLs. Ilcro tlio visitor will bo annoyed by all that coni<&leas jargon of runners and solicitors, so usual in iill tho great thoroughf:uvs of this country. There is a good carriage-road up tho bank, and if tho visltoi feels disposed, he can walk at his leisure, and thus have moro timo to contemplate an<l a]>])reciato this wondei-ful r^oeno. If ho jirefeif? riding, ho can get a good carriage, witii careful diivers, to take liiin to Tablo Rock, generally for twelve and a half cciit.'t It would bo advisable to mako a bargain before y»ya st.ii-f, as tho drivers will sometimes tell you they will cnrry you for a shilling, meaning Canada cuiTcncy. One shiliin<x of that money is twentv-two cents on fJiis sido. Prlco of carriao^es bv tho hour, for tlie party, on that side, is usually seventy-fivo cents. ex]-H^nso hy LUo cr.t('r{)rl.->in^' propilcior iias rf;ecntly Lfcn laid ouL in UiKlilioiu U) tlio balMiiig, \|)l<':kiuie« ganleii, and rosid-'iicos for i>iivato f;imili(\s. Jt i:ortiii'.lv is un cxcH'Ilout lueation, comniaii«Iiii<' a \IcW of tlio Atnoricjui and ili)r.iC5 Slioj JAuJ. K'l'^hiy i\»ds below, on tli'j o>l<^o of tlio kwik, is VicUiri* Point. Dirorlly opposite the Clifton Houhc, the othor sido of the street, i.s Mr. lloUoway's, oui* of the must cuilehrated arti.sta in thid coiiuLry. lie spends his tinio ip. p.-iiiitinj^ views of tlio FalU 'jeverid fiinall shopi'i on tlie road-side where Iiidian work and refrCiJiuientd arc sold. Is near Talile ilock. The galleries are arranpjed 80 as to represent an entire forest scene, aii^l eontain upward of ti'n thousand intore.sting specimens. Birds, Amimals, Fish, Minerals, &c^ a fjreat variety of which were collected in the inuuediate vicinity. Chartjiie for admittance, is 25 centa. 'J'liia includes the Camera Ohseura, Buflalocs, S:c. About twenty rods below the Museum, is the point where Miss Martha K. Kui;:; fell over the bank, one hundred anJ fifty feet perpendicular. (See Casualties.) The next grand, and all absorbing point of interest, »s Table block. Is on the Canada si Jo, connected vritU tlie great Horso Shoe Falls, and tlie terminus of tlio carriagoj'oad in this direction. It was formerly aLout fiftoea rods long, and tlireo wide, and projects over tlie precipicG from fifiy to sixty feet. Thousands of the mobt timid have stood upon this giddy eminence with perfect safety, and gazed upon the ro Bpleudent grandeur of this enchanting, liewilderiu^ scene. While contemplating it, tho mind is lost and sinks back upon itself, amid the immensity of God's works. And wo hazard not too much in say ing, there is nothing on the globe that compares with this vie'./, in point of sublimity and interest ' I have," said a sea captain to the writer, who had followed the ocean for forty years, " seen tho Maelstrom, the Burning Mountains, and all tho wonders of tho globe, but this is tho most sublimely interesting of all." Two la? go portions of Table Rock Lave fallen within a few years, but have detracted but little from this grand view. Directly ia rear, is the Prospecu House, on tho top of which is a Camera Obscura, and a splendid view of tho Horso Shoe, and the Rapids. The charge for seeing tha Camera, is 12 1-2 cents. If aat slieet, are exceodiiigly varlabl«. IL is atkiWu jible, perhaps, to our state of LerJtli, pliysieal courBi^e, or nervous temperament. Some ha\ e a ^ood deal of adventure in their constitutions — bekl, fearless and determined : as the interest of the scene increases, difficulties vanish. Otliers are ixiore timid and fearful, but equally resolute. And as far as the writer caL judge from the countenances and expressions of those who have accompanied him, the feelings that involuntarily arise, are those of religious awe. We may have been schooled in infidelit}^, and tauoflit to believe there is no God; but durinnr our stay at the Falk, and especially under Jheni, lot the individual bo «n Atheist, if ho can. (Impossible.) On returning, about fifty feet from tli© bottom of the stairs, lot the visitor pause fur a moment, and look up. " I did not," said a lady to the author, in company with her husband, from South Carolina, " fe! the least agitated while under the falling flood ; but at this point I trembled ; not from any real or apparent danger; but my nerves, for a moment, seemed to give way." She soon regainel her composure. " That Bcenc," continued she, " is worth a journey across the globe." and tlicir numbers are nearly equal to those of tLe gentlemen, and their courage often surpasses them No accident has ever occurred, unless from carelessness, or the iincallod-for adventure of some thoughtless traveler, in rushing out upon places where human beings never ought to go. There is an iron driven into the side of the rock, at the termination of the path. Visitors usually lay tlieir hands upon this iron. At this point you can see all that can be seen, with perfect safety. Two or three feet beyond this, your path is intercepted by a perpendicular rock, which rises twenty or twenty-five feet from the ajigry flood l)elow. This is called " Termination Kock." As much as to say, " you can approach me, with safety; but, beyond, you cannot go — here let thy proud steps be stayed." Some clamber down this rock to tlie water's edge ; but this is uncalled-for, as all the wildness of tliis magnificent place is seen without running the least risk. If the visitor has time, and feels disposed, the next object of interest is the Burning Sprino- — a ood carriage-road, and a delightful ride. This Spring is situated two miles above the Falls, on the Canada side, near the water's edce. It is the carbonated sulphuretted liydrogen gqs, thut burns. Touched with a match it gives out a b: illiant flame rising two or three feet higl). Many are very much interested, and to those who have never seeu any thing of the kind, it is an object of a good deal of interest. Charges, 12 1-2 cents. The villajvc of Chippewa is on the British side, two and a half miles above the Falls. A few soldiers have been stationed here since the Patriot War of '37 — '38. Landing of the British steamer Emerald, from Buffalo, N. Y. The terminus of the railroad from Queenston, connected with the British and American steamers for Toronto, Kingston, Montreal, and Quebf A steamer plies daily from Chipi^ewa to Butl'alo. Lundy's Lane, is a mile and a quarter from the Falls, on the Canada side. The battle, in its hottest fury, was fought priiicipally in the night, with the bayonet; Gen. Peter B. Porter commanding the volunteers — Generals Brown and Scott wounded, Ryal and Drummond, (British generals,) wounded and taken prisoners. This, it is said, was the severest battle ever fought on this continent. British had, in killed and wounded, 877. Americans, 860. The above wjis taken from General Brown's oflicial report to the Secretary of War. For a desci-iption of Drummondville, where tliis battle was fouglit, see largo niaj) by the author, accompanying this work. This is sometimes blended Tvith the Chtppewa battle, but it is a mistake; (Jhij»pewa battle was fought near tho Burning Spring. July 6, 1814. If the visitor ascends to the top of a high Pagoda, on the battle-ground, ho gets an excellent view of tho surrounding country. Charges aro from 12 1-2 to 25 cents. The visitor can return to tho Clifton House, and cross at the Ferry. Charge for crossing to the American shore, is 12 1-2 cents; if he rides up on the Cai-s, 6 1-4 cents more; or, he can continue his route to the Suspension Bridge, cross, and return to his Hotel on this side. (See Chapter 3.) On the' 2Glh of Juno, 1850, our citizens were st'utleJ M itli the report, tliat Table Rock liad fallen. Many of us instantly repaired to the place, to witness, for ourselves, an event wo liad long- expected. Tlio rocks lieaved, tlio earth trembled for a moment, aa if collectinnj her miirhtv enerixies to heave from her bosom this cumbersome load, niid hurl it, in Ppito of all resisting power, into 'he dark, yawning abyss below, which, like an enraged monster of the deep, devoured all at once, and whose voracious jaws are widtjly distended for another meal. Nearly half an acre, 200 feet long, 00 wide, and 100 thick, foil into the river, and almost every partiple disa^> peared from sight. The noise produced by thia fallen rock, was somediing like the rumbling of an earthquake. It was heard four or five miles on each side of the river. There was some fifteeji minutes pause, the earth was aginn in motion, and then another crash. The ponderous load rolled with the velocity of lightning, and sunk ftxr down into the deep below. Fortunately, no lives were lost, though some forty or fifty persons were standing upon the rock but a few moments before. A I Dlind man, ^vllo sells views of difTereut cities and the Falls, felt tlio rock begin to move, and succeeded in reacliing a place of safet'., just in time to escajx) tliis lieadlono^ phuigo. An omnibus Avas placed upon tliG rock for tha pmposo of washing it — two persons were inside — they jumped for life, and were saved. The horses were taken off to feed. It went over, and n(;t a fragment was ever seen. A gentleman and lady were below; several tons fell in the path, directly before them; tlioy lia.stenod to the top of the bank, and the whole wunt oil" at ouco. In 1818, a portion of Table Hock fell In 182S, u large mass fell from the center of the Horse Shoe Fall.^. Another mass fell, connected with Table Rock, and extending under the sheet of water toward the point of the Horse Shoe, about 150 feet long, 50 wide, and 100 deep, carrying with it a canal boat, that had lam on the verge of the Horse Shoe, for months. Thus nature, not satisfied with wliut she had done, moved on, silently but trium])haDtiy, (o destroy her O'siTi works. But the natural cause, the modus oporandl of these rocks falling, is the shale and marl below. These, by the action of the spray, frost, and the atmosphere, wear fostest at the bottom; and ■when they project sufficiently far to throw them beyond the perpendicular lino of descent, they crack .mid fiill of their own weight. Hundreds of ittstances about lIiG Falls, strikingfly cxomi^lify tlicso reniarlcs. There is one on tlio American Fall, near tlie shore. Another is seen from Luna Island, extendin':^ in a fissure toward the center of the American Fall; and a third is noticed a few rods from tho Tower toward the center of Horse Shoo. This commences near the Stairs, leading back from the edge about three or four rods, and varying in width from three to fifteen inches. It is about iTo feet long, and 80 deep, and is seen and pointed out bv almost every traveler who visited Tablo Rock. That portion which remains }>oises, a[»[)arently, upon a mere point, and is as destined to fall, as these waters are to roll, and it may go before night; but how long it will last, no mortal, this side of the other world, can tell. The citizens on that side have often threatened to put a blast into this ci'evice, and blow the whole off together, wliicli might easily be done. The visitor will be urgently importuned to go under the sheet of water by run ners who are eniplo} ed for the purpose, and if he wishes to do so he v»ill judge of its safety, for hintself, after taking the above facia into consideration. Dresses and a guide will be furnished at either of the Houses, at an expense generally of 50 cents. There are not tw manj who go under the sjieet of water since, as before the rock fell. My own opinion is, it is not safe. Formerly, wlior. tlio writer acted as a ijuiile, lie liad aceoin[»ani(j<l parties under the fallinnr Hood more than a liundred titnes at different periods; but no inducement could prevail upon him to go there now, though perhaps he has as much nerve as most men, yet in his opinion the risk is too great, to effect so little. It is true there is an indescribable something in some persons, perhaps the name of being under Niagara, which gives this impulsive desire; but when the novelty has pas-^ed, this anxiety has passed with it, .in<l the writer lias never known the ' :rson who wished to return there tlie second tiiL.i. There may be exceptions, but they have not come to his knowleilixe. While on the subject of falling rocks, it may bo proper to remark, that rocks wliich lay so thiek bo low tlie American Fall, have unipiestionably all rolled, at some ^■)eriod, from the high bank. This remark, in the opinion of Professor Lyell, and oth,?r geologists, liolds good in every pl.i-e, where largo rocks are seen at the bottom of the Falls. In 1 S i 5, a rock fell just above the Museum, (Canada siile,) 100 feet long, 40 wide, and GO thiek. The same year a large rock, weigliing several hundred t(Mis, fell near Biddle Stairs, on the west side of Goat Island, carrying with it, in its fall, a part of the roof of the Stairs. In 1818, immense quantities of A FISSURE IN TADLE ROCK. rock fell botwecn Biddle Stairs and the Horso Slioe Fall, blocking up the ])ath and rendering it dilficult to rot to the water's edge. Wo Lave time to mention but cue instance more. Sunday afternoon, Feb. 2d. 1852, a portion of the precipice, near the tower, on the South side of Goat Island, fell with a miglity crash. This portion extended from the edge of the island toward the tower, being about 125 feet long, and about GO feet wide, of a somewhat elliptical shape, and reaching from the top to near the bottom of the fall. The next day, another piece, triangular, with a base of about forty feet, broke off just below the tower. But the next great performance was the most remarkable. Between the two portions that had previously fallen, stood a rectiingular projection, about thirty feet long, and fifteen feet wide, extending from top to bottom of the precipice. This immense miuss became loosened from the main body of rock, and settled perpendicularly about eight feet, where it now stands, an enormous column, two hundred feet high, by the dimensions above. The severity of the winter, and the long continuance of the intense cold, have doubtless produced these results. They are splendid exhibitions of the power of frost, in releasing this mass of rock from its kindred stratum. It held it within its cold embrace for a moment, then luirled it, with the might of a giant, into the chasm bolow. And llicy stvikiip/ly (.'xcir.i.liiy tLo ioa.lt^oi) of rroft'ssur Lvoll, in rdl'ronco to the recession of tlio Falls, Avliich is louiul on another pr-go. If a filiin on firo at f^on, at night, in a tlinndorstovm, ift gnnul and terrific, no h^ss so 'sv.'ts tho st-'nrnboat Caroline in flriinos, as sho "w.'W loosed from her moorings at tho old landing, near Fort Sohlowsor, and tcsvcd out into tho middle of tho river, l»y the command of Col. McNahh, a I^riliph ofllcor. ITore sho \Yas ahandoned and left to her fate. The night uas intensely dark. Sho moved Bte.ulily on — a hroad sheet of lurid flanio shot high into the heavens, illuming thovostorn clouds with its rod glare — rockets were a'^eonding from tho Canada shore, exprcrsivo of the success of tho expedition. A universal shout ring's out upon the niglit air, from the pai-t}' ■wh.o havo just left tho doomed boat. She enters tlie r:ipids at tJic head of Goat L^land, nearci't tho Canada sliore, careens ovei-, rights, and ]iaspe.s on like a fiaming meteor, to her final doom. Sti'ikes n])OTi Cull island ; swings around, aM-fnlly shattered by the Ci ntlict, the flame" rolling on f >r a moment, not al'irmc d. l)y Niagara's roar, but as if detoiTnined not to bo encircled v'thin its cold embrace, or bo h'^'it^'u hv its mighty and terrific povrer. The war of tlu? elements continues for an instant — tho Caroline liaa disrippc.irci], leaving "not a wrcclc bcliIn(];"anJ Ninc^.im is victor, procLiiiiiiiig to tlio vorld thiit its jxAVor i.s not lessened l»y tlio stiifo of men, or any cu'wiii] ilo.'itiiic^ suLstniico ii['on its bosom. Vory few, Lowever, beheld this fijnuid speetnelc, na it v/as in tlio ii'i^'ht, and motjt of tiio iiihabit;iutii had retired from tile frontiers. It U liot our purposo, at this time, to enter into the ininu[i;c of this aO'alr; sullico it, the boat w:ls charged by tho liritisli Avith aiillng the refugees by cairyitig jtrovisions and anna to Navy Lslan'l, which doubtless was true. Tliis specification w;usbr. night before tho court by tho Ihitish con?ul rX tJio trial of MeLerjd for the iinirder of a gt'ntleman from Buiialo who was shot on boai'd tho Ciu'olino. It will be rccolleeted MeLeod was a<^]niiteiL The fragments of the boat that lotlged on (»ull T.-land remained tliero initil tho next s[iring. V»'luit wjLi left of her afler passing llio rapids, went over tlio point of tho TIoi-so Shoo lall. No pei'son, v/o bclifive, -wius on bo.u-d. I^eeember 29, 1831/'. As agreed upon by the Comnn'ssion(>rs, (fton. P. ' Vi. Porter was onn, on lu-lialf of the U. S. govcrn'^UiGut,) is in tho center of tho river, or (leepe.st elianhelj pas.sing through tho point of tho Horso Shoo, thVorjh tlie center of Lal.o Erie, Lako Superior, and }^ ^n to the northovn boundiu-ies of the UnitL-J Btatcs. lliis boat was attached to a rale of sjuv-Iogs, and used for cookinor and as a lodffinij-rooni for tlie liands ; but wbile attempting to tow this nift up the river from Chippewa, for the purpose of landing it on tlie American siilo, the rope broke, and the logs went over ; but the boat was carried, by the force of the current, on to a rock, the lower side nearly out of water. It remained so\eial months, but when the last poilion of Table Rock fell, it went over. la two and a half miles from the Falls, on the American side. It is memorable for its antiquity, and associations of the British and French, each holding Iternately the possession as early as 1775. In the month of August, 1851, the writer accompanied a party of Indians from the northwest wilds of Minesota, (on their way to Washington,) to the foot of the American Falls. The wind was favorable, and we approached within a few feet of tha falling sheet They gazed in rapt wonder on the mighty flood, as it rolled its angry waters, r^d fall upon the resounding rock below For a loug time, INDIAN OFFERING TO THE FALLS. V'.ivy si nscle of tlnMr countenances imlicitcd a Wiiglovs awo, and tlicir tiiouLdits a}'p(are(l to bo communing with r-ome superior power. At asign;d from tlioir cliief, tlioy drew a fsmall rod ]>!po from tlieir o'irdio, and 'willi a o;reat deal of solomn ir-^sturing, each tln-cw his ]iipo und^'r tlio Falls. This, I was told hy the interpreter, wa> a religious offcj'ing to the Great Spirit, that he would be pro}iitious to them, on their journey, and return thorn in safety to their homes. Was this superstition, or was it true devoti(^n ? "We thon conduct(^d tliem to tho Tower, on the west side of (xoid Island. Tliey were induced, by some ladies and gentlemen present, to give their views of what they saw. They did so, in the followinrj words, ?is far i\s their lan^ruaire could be interprete 1. "Brothers," said tho chief, "we live in tlie woods, far toward the setting sun. Our Fathers once owned these lands, and this river; they have told us of tliese Falh, but now we see them. Brothel's, you are great, but you cannot stop this water; you cannot put your hand on its mouth and make it still. Yonder," pointing to tho clouds, "is the gre^at Spirit; he male these, and this is liisAvork; and yonder," pointing to tho rainbow, (which at the time shono most brilliantly,) "we see his face — we see him smile. We shall tell our cliildren what wo have seen. Brothers, our beaiti are glad, that we turned a&ido from our patli, to see tLIs great wonder BroiLers, we tLank the uliitcs for our good treat ment." The cniotions of Hod Jacket, the celebrated Indiiui Chief, wliilo ^•i.siting tlio Falls some ycai"s tdnco, wero of a very different character. llf> admii'ed tlio grandeur vi nature's work, but not witli that religious awo and devotional feeling, ty did tliosG wild untutored sons of the forest, men tioned above. Envy and jealousy rankled in his' bosom against tho white man, the destroyer of hi^ nice. Ho saw, at a glance, the su]>eriority of the wliitos over the red man of the woods, and ho haled \|jim for that ho Lad not tho power to become his equal. Is a few rods to tho riMit of the Ferrv IIouso, on tho American side. This w:is the hust residence of Francis Abbot, tho Hermit of Niajxara. On this spot, a Pa.goda w^^s raised, which placed the specliv tor at an elevation of more than one hundred feet above the cataract, and two hundred and seventy feet above tlie river; but it ^\i^s taken down about two years since. Nevertholess, the view from this point is grand and imposing. 'J'liG American and Ho)"se Shoe; Goat Island with its stately oaks and dark waving forest; the opposite iron-bound shore; the river below, with the FeiTV Boats, dancing like* building of tho Pagoili, Auyfust 11, IbKJ. Thoso who Iiavc rambled o\'or tlio wild domain, And still doftiio to view it once a^ain. Enter tho fi;nrdon where an Abbott dwelt. And roam whore he, enraptured, c;a7ed and hnclt Si'ili even \rt those plaintive strains I hear, Ti'Iuch once he wakened — and the pensive tear Steals softlj o'er my cheelc, while tho full heart Essays to know what sorrow wlng;cd the dart "WHiich r-e»it liim forth a wanderer from his home, 'Mid tiiesu majestic scenes in silent grief to roam I Say, wanderers 1 wmdd yo dare the wild excess Of joy and wonder words can ne'er express ? Would ye fain steal a glance o'er life's dark sen. And gaze, though trembling, on Eternity ? Would yo look out, look down where Ood liath set Hia mighty signet 1 Come — come liigher yet, And from the unfinished Btmcturo gazo abroad. And wonder at the power of God I To the Pagoda's utmost height ascend, And sec earth, air and sky in one alembic blend I Btfncatli \-onr feet ^ic niiiibow'starch docliues, GIcaniiDg wiih rii'lior yomslliiin Iiidin'.s luiuejs; And dffp witliiii the gulf, yot farther down, '^id uii.st and foam and .spray, bubold Niagara's crown. T is finislicd, and llie steps I now ascend, "Wliilo jv.'oud Xiiitrara's waters round nje bond ; Tho' nerves may trcinblc, fears may fear alarm, Yet tlic Pnfjoda stands secure from harm : And, while 1 trembling,' wintl ils Iwfty Jiei^dit, I'stop to rest and rr.pturc tills the sii(lit — The trembling limb gives place to lirmer step, Tile summits gained ! maj:'>tlc nature 's met ! Ob rapttirons trv.ze, yet had I SIiaksp(!aru's }>cn, 1; would not — couid not take the prospect in. Wondrous, sublime, transcending all I -vc seen — There's sonuHliini,' more than languJi^je can explain Thoisc sparkHn':^ torrents froni those dizzy heights, Oildc'l ^^ilh Sun bv dav, and Moon bv nii'-ht : That WiUery mist, that f>»rms the radiant bow. Then fertilizes all tlie land below — That noble livcr, studded thiok with green ; Tliose roaring I\aj>ids ru.shing fiist between — The tranquil Lake above, in foliago rich I view, Following the scene, the Whirlpool rapids too — My eye 's exhausted with the rapturou3 gaze, My heart's expanded giving God the praise. place. TliE AUTUOIU The followino: fniirmcnt, written in tlio Roo-ister of tlio Point View Gai'don, at Nia'^ara Falls, on Sunday, August 1st, 1847, bj Dr. Baxlev, <;f Baltimore, illustrates tlie profound impressions produced on the mind and lieait by this i:iost \YonderfuI work of Nature. Here, near God's own great temple, would we bow In humble praise, and prayer ; and while the lip Rests silent, would the soul its homage give. And favor seek ; petitioning, that in The devious path of life, so may we move, That when these rocks shall melt with fernd heat;, When the rich garniture of teeming earth Shall vanish, leaving no trace of brightness Or of beauty, to tell that it once was ; This restless tide no longer flow, and its Deep cadence cease ; when the blue dome that spani The earth, shall pale away, and radiant spheres No longer shed abroad their hallow'd light ; Then may the hope, that rests upon His word Who ne'er was false to man, who hangs his bow Upon the cloud, and spreads it night and day Upon His altar's incense, token to man Aliko of his redeeming power, and will; TO NIAGARA. Thon may the hope that on His word relies, Nurtur'd by love, and rectitude, grt)W strong In trust, and prescience of a home " not mado With hands, eternal iu the Heavens!" Al'uust 1, 1847. From tliis primeval altar — the green and virgin sod — TJie humble homage tliat my soul in gratitude would pny To Thee! whose shield has guarded nie thro' ad rny Is on tlio Ainorlcan side, uLout sixty rods below the Forry, nnd this is tlio only wnj of goltino; to iL The hnuk is steep and preci])itous, nnd dillieult of access. It is about fifteen feet wide, and ten high. Except as containing a few sp(3ciniens of petrified moss, it is not an object of interest, and is seldom visited bj strange i-s. TliG time of sUvrtiiig on tliis excursion, fcr visitors ^.jiierally, is after brealifu.st. Tliis <^ivos Jinijilc^ tiniG to view Jill the places of interest in Canahi, and return before dinner, and be ready for the afterroon train. Most of visitors, wo think, in tnhing tliis route, prefer getting a carriage on this side, to take them all round, and return when thov p]l^^!■^2. The drivers will say that tliey will take you to Tal'lo Rock for two, three, and sometimes four dt.l'.ars. But the regular \ at the Livery Stable, for a f^ood carriaixe, is one dollar an hour. Others airain prefer ridino* to tlie Suspension Brido-o, and trettlDf; a carriage on that side, to take them to tlie llock or elsewhere. I can only say, if I were going myself with a party, I should g\:t a carriage on this side, for it is sometimes the case you cannot get a good one on the other side of the Bridge. The dilKrence in the expense is but trifling, and froqucjitly it costs the visitor mf)re, by d''pendiug on that side for his conveyance. One thing further before we sfart^ the vi.sitor will understand, and that is, whether ho pncjni^rr'.s a carri;i(ro by tlio lionr, or l»y tlio jcb; it (loos not iiu'ludo tlio ti)ll .-it tlio IJiilLjo, iuili'.>s a Kpf'^iiil liriri^iiiii is iiKi'lo to tliut elVeot. Tho tolls .'iro ns follows: at the <r:iU^ on tlio Pl:inl< lloail,goini; and returninrr, for a cirriaf^o 5 cents; at tho Sii?\|tcn,si()n ]lri !gn, for each pji.'ison'j^or goinp; over and reiurninc^ (if it is tbo saino day,) 25 cents, or 12 1-2 centa each way. If ho does not return, tlio cliargo is tho Eanic. For each carria<j^o drawn by two horses, go iii;jj and returning, is 50 cents — if he does not return, it is tho same, (i. e.) 25 cents for each passenger, and 50 cents for tho carriage besides. Tho above remarks aro deer..L-d necessary, because strangers aro sometimes deceived. Is two miles b(.'low the Falls with a good Pl.uik Koad leading from all tho Hotels on this side to it. Tlh' l^ridgo, whtMi completed, will not be surpassed for bold dariii:::, ami magnificent grandeur, by any work of a similar character on this continent, or perhaps on the; globe. Tho following table sliows tho Basket Ferry, and (lie temporary towers of tho Foot r>iidg(^, whon Mr. Elliott, his lady, and many of our citizens, both gentlemen and ladies, crossed over the river in a Basket, on a singlo wire, about an inch in diameter, tv;o hundred and thirty focit above ono of th"o ni.'uMost stroaiiiR on tlio globe. The Basket, with two and somethnea three persons in it, was suspended under the wire, and rundown on an inclined piano, by means of wdieels, very much at such an anL,de as the wires now arc. They would pass from the hi!.i;h towers to the center of the course, and then woul(J bo drawn np by a windl.-iss on the opposite sid^s and so vice versa. The usual time in erossini^ w;n from three to four minutes.* The work, under the supervision of tho enterprising engineer, Mr. Elliott, was ra])idly progressing, when tlie plank on the Foot I'ridge, which wero not bolted down, were blown otr by a tremendous tornado into the rajmU Six men wero at work on the bridge at the tim^'v two made their escape to tho shore — the fnnl structure next the tower was gone — four men wei o left at the mercy of the tempest, hanging with but two strands ofyNo. 10 wire to support them, and prevent their falling into tho rapids below. The wires to which they clung, with the tenacity of despair, oscillated with the utmost velocity sixty or seventy feet. The wind increased, and for a moment no power short of Omnipotence appeared capable of afibrding thera the least relief. Their cries for assistance were becoming more feeble and indistinct, until they died away and were entirely lost amid Itailroad Suspension Uridge: I-(Miu'ih of spiiii from centre to centre of Tou'ors 800 fcot li. i.,'iit of Tower above rock on tlio Ain'n si'lo bS " " .< << it ; Canad'u " 78 " Tlie novelty of crossinjj nnd coimectinc' Iho two Governments, by an Iron cliain/'-' was the bridj^'a first used irjtii of Marcli, 1848, built by Mr. Chas. EllioL It was a liijlit <ind airv structure, — a mero epider web, compared with the present substantial \l R. bridi^e. The first one cost less than ^50,0(»(». The bridge as it now stands, — one of the greatest engineering achievements in the world, was built under the control of John A. Roobling as EngiufT, and Architect, at a ct>st of about 8">00,0&(). It w;is a proud (lay for Mr. Roebling, Thursday, March Stli, 185'), wlicn he crossed by steam for tho first time, this wonderful structure. The carriage floor which will ;dso be used for foot passengei-s, is suspi nded 23 iiiLT over tiio awful Lrulpli bciicalli. TIic R. R. Brido'o is cciistrueted to iiicei tlio wants of all the lines cf II. 11. tliat centre liore. Thus althouirh there arc three distinct tracks laid HQvoea tlie brid';e, onlyono train can occnpy tlieni at once — all being within the coiu\|i;v;S of a G foot guago, and by au higenious Ci':'tri\ancoof switches, all possibiUty of danger from ojlli.sion is avoided. Afler crossinu: the bridixo take (ho left hand road ; tlii:> gives you a better view of the deep greeu river bt'luw you, the \|)erpcndicular, rocky banks for two miles, and you arrive at the Clifton House. For a dosoription of the several places you will visit, see Appendix. "WiiiRLrooL, on tlio Aiiiorican side, Is tlireo miloM bolow tlio Falls; there is an excellent carriage-road, planked tlio iii(-''st of tlie way. Expenses for carriage, one dollar per lionr. Passing tbrougli the gate near tlio Lank, twenty-five cent^ f(^r cacli perpon. This is entirely different from any thing which lias been seen about Niafjjara. After viowinix this wild freak of nature's work from above, let the visitor, by all means, go below. From a bench placed for the accommodation of travelers, let him stop about thirty f^et up tlio ri\'.cr. ITore commences tho v.-indinir circuitous st'iirwav that leads to tho water's edge. There is no place about Niagara .'is wild and terrific as thin. About half way down tlto bank is a smooth, flat rock, projecting over his path some ten fee.t. This M called the lialf-way house. Parties of pleasure frequently drink a bottle of champagne here in honor of the plac<?. At the foot is a small tree leaning toward the bank ; it would bo well to mark this, as it is the only place where you can ascend. While standing upon the rocks near the water's edge, cast yoia eyes up tlio livei' toward the Cnnada shore; you '.vill at onco jXTCoivc the river is vciy consiJerably high.or ill the center than it is on each side. It is e.siiiiiatcd by the Eno-inecrs, to bo eleven and a lialf fvct. If two men stand, the one -with his feet in the water on the American s:\d(}, and the other on tl;e Canada shore, and extend their hands as hia'h f\i tlioy can reach, with a handlcercliief or any thing of the kind in it;, it cannot be seen by either. \\q know of no way to account for tliis wonderful freak of nature, unless its being compressed v.ithin tho bfuiks, fi'.i.l meeting with such resistance on tho Canada sido, having to turn almost an acute angle, that it cannot find its way out as fast as it accumulates abo\e. Our business, however, is not to philosophize, but to slate facts. Tho "Whirlpool is visited by thousands for the wild and magnificent grandeur, of its scenery. The li^'or, in its wildest fuiy, THshes against a perpendicular bank about three liundr'-i feet high, producing a re-action, roaiing and swelling like some enraged giant strn^.rgling to bo free. Logs, and other bodio?., have been known to float in this whirl of waters for forty, and sometimes ninety days, before they could lind their Tvay out. One of tIie Ladies. How beautiful and clear, and yet how powerful and rapid! With what commotion it bounds away I Is this a branch of Kiagara ? , A. It is truly a wonderful river. ' Three and a half miles below the Falls is the Whirlpool ; and here a man by the name of Samuel Whitmore, of this township, threw a stone across to the Canada shore. Note. — In June, 1841, three young men, deserters from the British Ai'my, in attempting to cross the Niagai-a River in the night, below the Falls, were drowned, and their bodies were carried into the Whirlpool. For nearly two weeks they were floating round, amid the wrecks and floating timbers. The following remarks, by a gentleman who saw them several days afterward, are descriptive of the ■cene, and we ragret the writer's name is withheld* Drive on, Drive on ye ever curling waves. Still fall, rebound, and sink away, in deafening notes; let your AviJd cliorus peal, while from the shore, the trembling rocks give way, and roll destruction to tbe cavernod deep. Amazement fills my mind while I behold these awful depths, doomed to perpetual strife, to agitation, and unceasing war. Those barriers firm, the rolling waves, within the bounds prescribed by Him who made them for his pleasure and at his word piled -high, those monumental rocks. The powerful stream has rent aside he earth, and far below the hills, and the surroundng plain has sunk its course, sweeping resistless on ta way, till, where old time on yonder lofty point has raised, for ages past, his throne of massive rocks, he bids the waves be stayed ; receding back affrightxjd from their course, adverse they flow to nature's general law. The mighty flood reels like a dmnken man, it wreths and foams. The angry Whirlpool ronrs, till forced bcue:itli, tlio rusliiiig eddies sink, and nil .-ibove tlte torrent ovt}r^vllel^lino•, spreads abroad. Forced from below tlie imprisoned waters gush, and pluncje exultino; on tbeir course. Teri'or Ler ever w:il\oful vio-ilr, kccp>!, find frig-btful death presents liis Joatbsome front. E'en now liis work is I'iding on (lio deep, in mystic maze around, submissive Iicre. And tlicre, liideous to siglit, amid broken wrecks three human forms appear as in liA^; ^^!lh arms outspread upon the tossing v/aves, tliey whirl in the teriific da'.u'e of dt.'illi; in waving unison above ihr.'w licads, in snovr-wbile ]>]umes the screeching gulls repeat their cry, s'i:l, sliiill, and dissonant. It is their banquet, r,nd to them their notes, amid their feast is sweet and iv.usical. It even was voluptuary's song. Lnte, in t]ic?c forms high expectations bhized, of hi v'lfy, of hope, of liappir.G.-v, the i)rom!sed hmd in view, comfort, long life, freedom and all the aspirations which man's fond heart revels rejoicing in, Avhcn the rapt mind tho glorious future paints. Thy stream, Kiagara, Jay midway between the prospect of their visionary joys. They trusted to thy cold embracing waves, ' and they arc thine; cut off from hic they perished while hope's bewitching flowers were blossoming for them. Thou ruthless stream upon whc;;o ];eavi:^.g bosom they are borne, night after night its lonely darkness spreads, and day succeeds to day, still thou DEVILS HOLE. cradlCvSt tliem in cruel mockery of this world's hope. How did they give up life; and villi cold death, with wli;iL strong nguny did tliey eontend! ^VIlat prayers arose, what thoughts, what words were theirs! How, 'mid tho w.nes, they cheered each other on. Hold on, the shore \a near! I see it there. Help, my strength fails, I slide — have mercy. Lord ! "Who knows hi.s lot, A\hen will death strike his blow; 'mid gurgling Hoods shall our hibt struggles ho, or shall our doom in instant vengeance fall, our bodies riven by the Hash of Hea\en ? On returning to the plank-road, through a delightful grove, if the visitor wishes ho can ^i>il the Bloody Run, or the HovilH Hole. It is about a milo below, and Chasm Tower in the ueiglibcrhood. Is three and a half miles below tho Falls on the American side, formed by a chasm in ihe ea.-torn bank of the river one hundruj iifly or two liundi-ed feet deep. An angle of this gulf is witliin a few feet of the road, oflering the tiateler, ^\khout alighting, an 0]>p(n'tuni!:y of looking into tho yawning abyss beneath. During the French wai-, a detachment of the Ihitlsh armv, while i-etreatlno; from Fort Sehlosscr, (about ii\'e miles soutli,) were decoyed iuto an ambush of Fiendi and Iiuliaiis. The yell of tho savage, jus it rung out upon the luklnight air, was tho first indication of their attack. Baggagowjigons, oiHcera, men, woinfn and children, were encircled and pushed over tho bank, and plunged into the awful chasm below. I'y the most authentic account, tho number who perished is two hundred and fifty. Their bones lay bleaching for yeai-s, and some of thcra aro to be seen to this day. Two persons only escaped ; a drummer who was caught in the branch of a tree in his descent, and a man by the name of Stedman, (the same who put the goats upon Goat Island ;) while attempting to flee, tlie biidle-reins were seized by the savnges; he instantly cut them loose and escaped. The Indians afterward gave him all the land he encircled in his flight, which was the point between the Devil's Hole and Fort Schlosser, including tho Falls. The visitor can descend tho stairs to tho water's edge if he chooses, but, like tho "Indian gun, it costs more than it comes to." What has produced this wonderful chasm, is left much to conjecture to dotermine. Professor Lyell thinks the small stream that pours over into the gulf, hear an old saw-mill, would have been "perfectly competent to have cut the ravine, and we need look for no more powerful cause." The battle above mentioned, occurred 1 7 65. Charges for going on to the rock, and descending the stairs Mount Eagle, is a few rods below. Is three and a half miles below the Falls, American side. A panoramic view, the specular medium on the top of the Tower, through which the landscape is viewed in varied and glowing colors, the deep gulf, the infuriated river, as it roai"s and rushes with the velocity of light, the Canada shore, Brock's monument, make it attractive, and visitors are generally interested. Charges twelve and a half cents for ascending the Tower, seventy-five feet high. Two miles below the Falls, usually makes three trips a day, passing American Fall, Goat Island, Horse Sh- I'till, and returns to her landing just above ihe r pension Bridge. Tho boat makes her trip m about tiiirty-five or forty minutes. If i\| C I( iT) e i\| ^l)b G l\| I () C 3 . There is generally carriages to be had at any time, and at all places that you may be; for the hackmen make ijfc a business to hunt up parties, and carry them who.sver they m ^y want to go. There arc also persoLs who act as guides, and who go with There is nothing here that has the shape of a village. A few scattering huts, most of them log-houses, arc all that can be seen. A ride to the meeting-house on the Sabbath is frequently made — pleaching in English by a missionary, and interpreted into tho ji idian language bj the chief, or one of the tribe. Itey are the Tuscaroras, formerly from North Carolina, once a powerful, warlike tribe, but are diminished away to a mere handful. Their women are at the Falls nearly every day during the visiting sea6on, and are very ingenious in making bead-work, which they offer for sale. Charges for a cai-riage to the village, there i^ no definite price ; generally from three to four dollars. No place in the United States can boast of a greater degi'ee of uninterrupted health than the Falls. Not an epidemic, or case of cholera has ever originated here, though the fell destroyer has laid low many citizens at Buflfalo, Tonawanta, Lockport and Lewiston ; yet wo have escaped. This is attributable, doubtless, in some degree, to the rapid current of the river, and the pure and exhilarating state of the atmosphere. Whatever may be the cause, Some strangers visit the Falls with all the implements for a long and successful chase among the buffalo, bear and deer ; but nothing of the kind ia ages, Iiavo roamed fearless tbroiigli tlie forest here; but now tliey are all gone — a few squirrels, pheasants and duclis are only to be met with. Ooeasioually a bald e;iglo is seen sailing high in air, whose eye is not dimmed by the noontide blaze, aijd dai'ting its fiery look upon the multitudes who congn> gate upon the banks of this mighty river, and with a piercing scream, soaring away to the lands unknown. At Fort Schlosscr, two and a half miles above the Falls, a few Avhitc and black bass are taken, and those who arc expert, often catch the pickei'cl and the pike, and considerable quantities of dillerent kinds are sometimes taken in nets. The angler is frequently more successful below Biddlo Stairs, west side of Goat Island. if 0 f e I ,s . Tho Cataract House lias lone: t)een consideied Rinong the first cIjlss bouses in tlio United States. The International Hotel is also a new and first class house, centi-ally located, with spacious rooms and eleg-ant a]»pointraent8. Tho Eagle, the Empire, tho Falls Ilotid, tho National, the Franklin House, tha Ningara, tho St. Lawrence, tl i Averil House, tho Chir(;ndou, tho Rochester House, and he AVestom Hotel, are all Houses well patronised during tho Visiting Season. Situated at tho Falls, was founded by the bequest of tho person whose name it bears, for tho educatioii of orphan children of parents belonging to the Episcopal Church. The great Indian store directly opposite the Cataract House, is the most extensive in the state. At the old Curiosity shop, toll-gate, and on Goat Island, are also largo assortments of Indian, moose-hair, Quaker and other kinds of work for sale. Professor Lyeli says : — " The fii-st feature which strikes you in this region is the escarpment, or line of inland cliffs, one of which runs to a great distance east from Queenston. On the Canada side it has a height of more than three hundred feet The fir«l question which occurs when we consider the nature of the country, is, how cUfFs were produced ; why do we so suddenly step from this range to the gypseous marls, and then so suddenly to the subjacent shale and sandstone. We have similar lines of escarpment in all countries, especially where the rock is limestone ; and they are considered to be ancient sea-clifFs, which have become more gentle in their slope, as the country has emerged from the ocean. You may perhaps ask if the Ontario may not once have stood at a higher level, and the cliffs been produced by it action, instead of that of the ocean. Some of you may have rode along the ridge road, as it is called, that remarkable bank of sand which exists parallel, or nearly so, to the present borders of Lake Ontario, at a considerable height above it. I perfectly agree with the general opinion respecting this, that it was EECE88ION OF THE PALLS. the ancient boundary of Lake Onturio. In somo parts of it fresh water shells have bi^en found. You cannot explain the escarpment hy the aid of the action of the lake, ft^r it extends f;irther and not in the Barae direction. When the land emei-god gradually from the sea, as it is now doing, the sea would natu rally create those sea-clilFs, and during the upheaval they would of course become inland. In Europe, proofs that limestone rocks have been washed away are abundant. In Greece, in the Morea, this is especially conspicuous. We have tiiere tlireo limestones one above the otlier, at various distances from the sea. Along the lino you may see literal caves worn out by the action of the waves. The action of the salt spray, which has also effected a sort of chemical decomposi'jon, is also easily to be observed. So completel) s this the case with eacli of these lines that you cannot doubt for an instant that hei-e is a series of inland cliffs; and this phenomenon being so certain in the Morea, leads us by analogy to infer that these escarpments of the distiict were produced by a similar cause. It is not disputed that there is some change going on at the falls, even now. There occurs, us we know, occasionally a falling down of fi'agments of rock, aa may be seen at Coat Island. The shale at the bottom is destroyed in consequence of the action of the epray and frost ; the limestone being thus undermined, falls down ; and it has beeii belioved that m this way thero has been a recc^sfeion of about fifty yards in about forty years; but this is now generally admitted to have been o\'erstated. I'here is at least a probable recession of about ono foot every year : though part of the fall may go back fjister than this ; yet if you regard tho whole river, even this probably will be soraethinjx of an exarjinjeration. Our obsen'ations upon this point are necessarily imperfect; and when wo reflect that fifty yeai-s ago the country was perfectly wild, and inhabited by beai-s, wolves, and here and there a hunter, we shall think it surprising that we have any observations at all, even for such a period back. Wo have an account of tho faUs, given by Father Hennepin, a French Missionary, who gives an exaggerated description of them, and yet one which is tolerably correct. He represents a cascade as falling from the Canada side across the other two. He says that between Lake Erie and Lake Ontario, there is a vast and wonderful waterfall ; after speaking of this, he says there is a third cascade at the left of the other two, falling from west to east, the other falling from south to north. Ho several times alludes to the thu'd cascade, which he says was smaller than the other two. Now, those who consider that because Father Hennepin gave the height of the falls at six hundred feet, small value is to be attached to his testimony respecting any part of the country, do biiu injustice. I tliink it perfectly evident tliat there must Lave been such a third ciiscade, falling from we.st to eiLst, jls that to which he alludes. A Danish naturalist, in the year 1750, who came to this country and visited tlie falls, of which he has also given us a description, which was published in the Gentleman's Magazine, in 1751, also gives a view of the Falls. In its general features his description agrees well with that of Father Hennepin. He went seventy-three years after liim, and there was then no third cascade. But the point where Father Hennepin had put liis cascade, he had marked, and says that, " that is the place where the water was forced out of its direct course by a prodigious rock, which turned the water and oblijxed it to fall across the falls." Ho goes on to say, that only a few years before, there had been a downfall of that rock ; which was undoubtedly part of the table rock ; and after that the cascade ceased to flow. Now, it does not appear whether he had ever seen Hennepin's account or not, he only mentions the fact that there had been a thirl cascade; and it is a striking confirmation of the accuracy of Father Hennepin's description. We find these two observers, at an interval of seventy years apart, remarking on the very kind of change which we now remark as having taken place within the last fifty years; an undermining of the rock, and a falling down of the hmestone, and a consequent obHtcrfition of tlio fall. Every one wHa hafl visited the Falls, on irKiulriiisj of the ^uik-s about the ohaiigos that have taken place, may have been told t'ittt the American Fall has become more crescent shaped than it was thirty years ago, when it was nearly straight. The center has given way, and now tl ere is an indentfition of nearly thirty feet. The Horse Shoo Fall also has been considerably altered. Jt is not of so regular a crescent shape as formerly, lut has a more jagged outline, especially near Goat Islund ; it has ^ess of the horse-shoe shape, from which it derives its name, than when it wjis given. It is qui^o certain that things there are not stationary ; and t .10 great question is, whether, by this accion, tbo v/holo Falls have been reduced in this manner. Fi'om representations made by other travelers, I was desirous of ascertaining whether fresh water remains were found on Goat Island, as had been said; for it would bo striking, if on this island there should be a stratum of twenty-five feet of sand and loam, pebbles and fresh water shells. They were found there, and I made a collection of several species of shells found on the island ; among them were the planorhis^ a small valvata and several other kinds. They were of kinds generally found living in the rapids, in the river above, or in the lake. since, tliere were found a great number of sluills, and al.so a tooth of a mastodon, sonvo twelve or thirteen feet below the surface. It waa the comii;on Ohio mastodon, and must have been buried beneath these twelve or thirteen feet of fresh water deposit, one layer at a time, each containing dillerent shells. In answer to my question, whether similar shells were ever found lower down ? the guide said he would take mo to a place, half a niilo below, where the strata had been laid open. Wo found there deposited in the rock a small quantity of fresh water shells, showing that this old deposition extended down to that distance. Here we have proofs that the river once stood at a higher level, and in a tranijuil state; and there is every appearance of the rock having been like a solid barrier to iiold the waters back in a lake-hke state, so that they might throw down those fresh water deposits at that height. You will understand this better, if you consider that if tho Falls go on receding, no matter at what rate, — an inch, a foot, a yard, a year, — in the course o^ time the whole must recede considerably from its present condition. "What proofs should we have of this afterward? You will easily see that if the river should cut its way back to a certain point, the effect would be to remove the rocky barrier, the limestone of the rapids, which has been sufficient to pond the nver back. But if the river cuts ita way back, this barrier could no longer exist; the channel would be deepened, and tlie deposits existing high and dry upon the land, would become proof of the recession. This kind of proof we have, that the Falls have receded three miles from the Whirlpool, the limestone having been higher at the Whirlpool than the river at the Falls. It may be well to say, that the beds all dip to the south, at the rate of about twenty-five feet in a mile. In seven miles the dip causes a general rise of the platform to the north, so that when at the top of the cliff, you are at a gre."er height than the level of Lake Eric; and if the Falls wore formerly at Queenston, their height was probably near double what they now are. Mr. Hall suo^jxested that at that time the whole fall was not at One place, and I think it quite likely that such was the case. There is reason to believe that one fall was upon the quartzose sand below, and the other on the Protean bed. The upper part would of course recede ftister than the lower, because it is softer, as is seen to be the case at Rochester; but the limestone becoming thicker and harder, would recede more slowly. There may have been several falls, as at Rochester, each one of them being le^s high than at present, and yet the whole being nearly double its present height. that the bed slopes at that rate. This slope of the river, and then the upward slope of the platform, are the reasons why the Falls are now of less height than formerly ; so when we carry ourselves back in imagination to the time when the river had not i;eC€ded so fur, we have a barrier of limestone much higher. The valley in which the river then floved must have been much narrower than its present ravine. The distance now from the Canada to the American side is about three quarters of a mile, whereas at half a mile below, it is only half that distance. deposits lower, will give more precise information. You might suppose that if we find the remains of a mastodon in a fresh water deposit so lately laid dry, as th;it near the village of Niagara, and only twelve feet below the surface, the mastodon has lived in the country at a modern period; you might think that a few centuries would have been sutlii-'iont for the accumulation of twelve feet of shelly sandstone and limestone, and that it may have been recently that this mastodon was buried, when the barrier was at the Whirlpool, before this twelve feet of fluviatile strata were deposited. Yet these strata are older than the Whirlpool. the place called the Devil's Hole, or the Bloody Run, the ravine roust have been cut by some more powerful cause, than by a slight stream. But this I regard as no objection at all, for on examining the nature of the soil, &c^ I am convinced that even the small stream which now flows, wouU have been perfectly competent to cut out the ravine^ and that we need look for no more powerful cause. Suppose the Falls once to have been near Queens* ton, they would recede differently at different times; faster when the soft shale was at the base, at other times slowly, when the hard sandstone was to be cut through. First of all comes the quart zoso sandstone for a certain distance; then the falls recede slowly, but more rapidly when it came to the soft shales. Then comes the sandstone again at the base, which now extends to the Whirlpool, and here the movement was slow. It piobably stood for ages at the Whirlpool. Then for another period it receded more rapidly ; and it is probable that for the last mile, its recession has been comparatively slow, because the Protean group, and about twenty feet of sandstone, making about fifty feet of hard rock at the base were to be cut through. It is certain that the movement now is at a faster rate, as the shale is exposed." saiPQ conclusion. Is an Indian word, from Onyakarra, supposed to be the Iroquois language, as they were the first who dwelt here, as far as we know. The meaning of the term is "mighty, wonderful," thundering water. It lies in latitude 43 degrees, G minutes north, and longitude 2 degrees, 5 minutes west from London. NIAGAllA IN THB WINTEIl OF 1855. The almost unparalleled severity of the Win'^r of 1855-6, was not without its eircct on the I' alls, causing a combination of the rarest ice formations, perhaps, ever presented in their history. Then tha Northern King had full sway, and the frost worked its wonders on tlie water, turning the river into hard, unyielding granite. The silence of the grave hung over nature, broken only by the eternal roar of that descending cataract, as the torrent rushed amongst the gigantic columns and magic shreds of ice. Facing the Horse Shoe Falls rose mountains of ice, resembling the vast glaciers that repose on the sides of the Alps, while in each crevice and hidden nook were fairy scenes of loveliucss and beauty, the sole work of frost and spray. Strong as was the iron grasp of Winter, petrifying in its power, that eternal (flood unchecked descended, colder in its aspect, darker 'and more mysterious than in Summer is its expression. Lake Superior is the greatest body of fresh water in the world. It is near the north-west boundaiy of the United States. A small riyer flows into it from the north, fed by the red lakes in Canada. tude from London. It is 459 miles long, 109 wide, and 800 feet deep. In the neighborhood of Lake Superior are the greatest and richest copper mines in the world. The following are the principal rivers that flow into this inland sea: Taquamenaw, White Fish, Two Heaii, Prairie, Chocolate, Dead, Garlic, St. Johns, Huron, Keewitiwana, Misery, Flint Steel, Octonagon, Iron, Camp, Montreal, Chippewa, Wisconsin, and several smaller ones, making forty-five small and three large rivers that empty into this lake. On the Iron river are perpendicular falls of more than 600 feet, and some of the rivers are large, and navigable for hundreds of miles. The outlet THE CTFER LAKES. of Lake Superior is ine Straits of St. Mary^s. It is 05 miles long, and pours its watera into Lake Huron. This lake is 218 miles long, 180 wide, and 500 feet deep. Tlie boundary line between Canada and the United States passes through the center of this lake. Lake Huron receives the waters of Lake Michigan, through the Straits of Mackinaw, which are 15 miles long, and 10 broad. The following are some of the principal rivera that empty into Lake Huron : Saginaw, Ausable, Thunder Bay, Cheboygan, Cass, Tiltibawasse, and several smaller ones. Lake Michigan is 300 miles long, 55 wide, and 200 feet deep. Some of the principal rivers that empty into Lake Michigan, are : the Betseys, Manista, Natipekago, White, Mashegon, Grand, Kalamazoo, St. Josephs, with eight smaller rivers. Green Bay empties into Lake Michigan, on the north-west corner. It is 100 miles long, 20 wide, and '75 feet ieep. Green Bay receives the watei-s of Fox River, which is the outlet of Winnebago Lake. Menomonee, Peshtigo, Oconto, and several streams of smaller size, discharge their watera into this Bay. All the watera of the upper Lakes, the wonder and admirati"^ of the world, are united and empty into the St Clair River, 40 miles long, and 35 feet deep. St. Clair River discharges its waters into St. Clair Lake, which is about 95 miles in circumference. The ©uUetof this lake is the River Detroit, 27 miles long, and twenty-five feet deep, v Mch empties into Lako Erie, which is three hundred and ninety miles long, sixty-five wide, and nine hundred feet deep. The Sandusky, the Grand, the Cuyahoga, the Maumee and several smaller rivers empty into Lake Erie. Such are the sources of Niagara River — inferior for splendor, grandeur, and magnificence to none on the globe. The outlet of ten lakes and more than one hundred rivers, it drains, from both, a surface of over 150,000 square miles of water. Lake Erie is three hundred and thirty-nine feet higher than Lake Ontario, (distance thirty-six miles,) and five hundred and sixty-five feet above the level of the ocean. Niagara lliver falls from Lake Erie to Goat Island, (twenty-two miles) twenty-five feet; from the head of Goat Island to the main fiill, ( half a mile) fifty-two feet; perpendicular height of the Falls on the American side, one hundred and sixtyfour feet; on the Canada side, one hundred and fifty eight; from the Falls to the "Whiilpool, (two and a half miles) sixty-four; from the Whirlpool to Lake Ontario, (eleven miles) twenty-five; total, three hundred and thirty-nine. We will now briefly notice some of the most important places we have passed from the head waters of Lake Superior to the Falls, and then start on our northern tour. which, when the country becomes more settled, must be extensively used. The Straits of Mackinaw connect Lake Michigan with Lake Huron. It is a military post. The Indians assemble here once a year to receive their annuity from the United States government, Detroit is eighteen miles from Lake Erie, situated on a riyer of the same name. It was formerly a miUtary post of the French, and a great depot for the fur trade. It is now the seat of an extensive conMnerce. Population 20,000. The Michigan Central Railroad commences at Detroit for Chicago, Distance two hundred md sixty-eight miles. Amherstburgh, (Upper Canada,) generally known by the name of Maiden, is at the mouth of the Detroit River, where, during the last war, a very severe engagement between the British and Americans was fouffht. The bones of seven hundred of the bravest sens of Kentucky lay bleaching upon the earth, the victims of the most wanton perfidy ; but the British paid dearly for this outrage, at the battle of the Thames. s: •^•-•ij^.^i Sandusky is in the state of Ohio, on a bay of the game name near the head of Lake Erie — a thriving, commercial place. Cars leave daily for Cincinnati. Cleveland is handsomely located, and has great commercial advantages both by the lake, Ohio and Erie C&nn] and the Cincinnati railroad. storm. DuNKiiiK, (N. Y.,) of necessity must bo a place of great importance, it being the terminus of the New York and Erie Eailroad — through to Nevr York in eighteen hours. Buffalo, at the outlet of Lake Erie is the great commercial emporium of western New York. It has no rival in the Ertipire State. Th^ capital invested, the enterprise of its inhabitants, the amount of business done, cannot be surpassed. Several of the buildings are grand specimens of architooture, and would do credit to any city in America. Population 50,000. Seven trains of cars leave daily (Sundays excepted) for Albany, Saratoga, Boston, pjissing through Rochester, Canandaigua, Geneva, Auburn, Syracuse, Utica, Schenectady, &.C. CIIAPTEIl VII. Having accompanied tLe tourist to the sources of Ni.'igara, we will now start on our northern tour to Montreal and Quebec, and see wlicro the mighty river empties. But before wo leave, wo will count up the distances, which are as follows: (Canada side.) By tho Canadian mail line, passengers go through from Niagara Falls to Montreal, in thirty-six hours, passing tho Thousand Islands, and the River St. Lawrence by daylight. A short description of the places we pass on our route from the Falls* to Montreal, Lake Champlain, Saratoga, (fee, will now bo given. Lewiston is seven miles from the Falls, at tlio head of navigation on Lake Ontario, lliis place, together with Niagara Village, Black Rock and Buffalo, was laid in ruins in the war of 181 2-1 o. " There can be little doubt," says Professor Lyell, 'that the mighty cataract of Niagara poured its immense volumes of water here, and by a constant abrasion has receded seven miles." KORTIIERN TOUR. QuEEXSTON is directly oi>posito liOwislon, at tlio foot of tho heights generally known as the "baltlo of Queenston Heights." The banks below the vilhigo are seventy icet high ; abo\o, two hundred and tliirty. The river is six hundred feet wide. A suspension bridge is now conipletet.! across the river, owned by a joint stock con)])any of Canadians and Americans. Dimensions: ten wire cables; distinico between towers, 1040 fett; tolal length of cables, 12-15; length of road- way, eight hundred and fortynine; width, twenty feet; it is estimated to bear eiglit hundred and thirty-live tons without breaking; cost, £12,000 or 800,000. Bkock's Monument is on Quoonston Heights, (Canada side.) Height, one hundred and tv/ent}six feet, and from top to the level of Kiagaia lliver, three lumdi'cd and ninety-six; number of ste])s, one hundred and seventy. It was attempicd to be blown up by one Lett, a Frenchman, who nearly lost his life, by this savage freak of revenge. Tho following memorial is inscribed on the monument : " Tho legislature of Upper Canada has dedicated this monument to tho many civil and militaiy services of tho late Sir Isaac Brock, Kniglit, Commander of tho most honorable Order of the Bath, Provincial Lieutenant Governor and Major General, commanding his ^raj(?sty's forces therein. He fell in action on the loth of October, 1812, honored and beloved by those whom ho governed, and d^ plored by his Sovereign, to whoso services liis lifo bad been devoted. His remains aro deposiiod in this vault, as is also his aid-do-carap, liieutenant Colonel John M'Donald, who died of his wounds, the 14th of October, 1812, received tho day before in action." Fort Niagara, seven miles below, (American side,) stands in the angle made by the eastern bank of the river and the southern shore of Lake Ontario. It is in the form of a triangle : one side commands the river, and Fort George on the oj>posite bank ; another faces the lake ; tho third is to defend the plain in the rear. From the light-house, the view of the lake and the opposite shore is only limited by the power of the human vision. Directly opposite is Fort Massissaga; a little above is old Fort George ; just below is Newark, burned by General McClure in 1813; directly across the Jake is the city of Toronto; to the west is Burlington Heights. If this old fort could speak, it would tell of the battles fought, the victories won, and a tale of intrigues and horror, that, even at this removed distance, thrills even the stoutest nerves. It was built by the French, 1725; passed into the hands of the British by the conquest of Canada; surrendered by thorn to United States, 1706; t^ken and burned by the British, 1813; and surrendered again to the Americans on the restoration of peace. Fort George, or Newark, is directly opposite. The village was burnt during the hist war; which event was followed by the burning of several frontier villages on ihe American shore, aa retaliatory. Fort George, near the village, is the most prominent, nnd perhaps the only object of interest presented. It is in a state of tolerable preservation, and has generally, since the war, been occupied as a gai'rison, by a small number of British soldiers. Toronto, the greatest commeicial city in Upper Canada, is on an arm of Lake Ontario, thirty-six miles from the mouth of Niagara River. It affords one of the best harbors in the world ; a thousand ships of the line can ride hero in perfect safety. It is one of the most independent military posts in the province. Two or three regiments of soldiers are usually stationed here. The Parliament House, the governor's residence, and many other buildings are fine specimens of architecture: population 30,000. Daily lines of steamboats cross to Hamilton, Niagara, and down the lake to Kingston, Montreal (fee. The first place the boat touches at, after l€a\ing Toronto, is one of tlie best harbors on the hike. CoBOURG is seven miles from Port Hope ; a small plac'^ and it would be diilicult to call it a seaport, for nothing of the kind indicates it; population al)Out 2000. A steamer runs from Toronto to the month of Genesee lliver, (American side,) and touches at Port Hoj^e and Cobouro-. The width of the lako at this point is eighty miles. Kingston contains 10,000 inhabitants, mostly French. It is near the outlet of Lake Ontai-io, one hundred and ten miles from Cobourof, and two hundred and tliirty-four from IsMagara h\x\\:. It is a strong, and one of the most important military posts in U})per Canada. The fort commands the entire entrance of the harbors and the navy-yard ; and next to Quebec it is undoubtedly the most impregnable fortress in North America. If the tourist has time, he would be amj)!^ repnid for spending a few hours, or a day heiT!, as there are many things to interest and instruct. The fort, navy -yard, messhouse, barracks, etc., can ail be viewed by apulyirg to the sheriff, or commandant of the station. About six miles below Kingston connnences the Tliou&Tind Islands; the largest is Long Island, thirty miles long. The most important cascades are the Lachlne lia2)ids nine miles above Montreal. The boat, like a trained I trained ^rar-horsG, Gnt':^rs and passes tliroiigh tlieni like an arrow of light; nothing can be more grand and torritie. The an<jfrv river dashino: a<>:ainst bare rocks within a few foot of tou, th'it liave lifted their frowniniTf heads for a2:es above the enrar .1 waters, Bniiliiig at its power, and bidding defiance to its rage; but in a few moments yon are at tlie dock of Montreal. 'Visitors can take the cars at Lachine for I^Iontreal if they choose, or continue on board tho boat; one, in our opinion, is as safe as the other; fare tho same. Wo have passed so rapidly, v,'0 had not time even to note tho difterent places; between Kingston and !Nfontrcal, are Cananoque, Brockville, Prescott, Williamsburg, Cornwall, Lancaster, Coteau du Lac; all small places of not much note, inhabited by English, L'ish, Scotch and Canadians. Is on an isl aid thirty miles long and six broad. It presents an imposiug appearance; it hes along the St. Lawrence nearly tliroe miles; a heavy ■wall surrounded it, but was thrown down by authority of government. Tho Hotel Dieu, is a huge mass of stone, erect'xl in 1644; about thirty nuns, unJer the direction of a superior, reside here; acts of beneficence and charity occupy their time. It contains ... cathedral, the English church, seminary, convent of Recollets, and the sisters of Notre Dame ; the general hospital, convent of Gray Nuns, v/as erected in 1753, under the immediate supervision of a superior and nineteen nuns. There are many splendid public buildings; the new cathedral, for its capaciousness, style, and the grandeur of its decorations, is not surpassed by any edifice of a similar character, in America. Nelson's monument, the museum, college, parade ground, are all objects of interest, and attract the attention of the visitor. A ride round the mountains of Montreal is most delightful ; they are seven hundred feet above the level of the river, which sweeps its angry waters, in wild and tumultuous fury post you. The tourist can visit the nunneries, and all the important places, by having a citizen to accompany him, or procuring a pass from the chaplain or commandant of the different stations. The principal rapids before you reach '.lontreal, are the Longue Sault, the Cedars,* and the cascades of St. Louis; they are nine miles in length, and are passed in less than twenty minutes, (about twentyeight miles per hour.) • It was at. the rapids of the Cedars that General Amherst's brigade of three hundred and fifty men, on attempting to descend in hoats, for the purpose of invading Canada, wero all lost, owing to the inexperience and bad management of the pilot ; not a soul survived. The first intimation the citizens of Montreal had of the invasion, wu the dead bodies ficmting past the town. NORTnEIlN TODR. We will now invite the tourist to accompany us ti Quebec ; distance from Montreal is one hundred and eighty miles. Splendid steamers ply between the two cities twice a day. If we take the evening' boat, which leaves immediately on the arrival of passengers from the lake, we shall arrive at Quebec about seven or eight in the morning. We first pass from Montreal, a foit on St. Helen's Island ; we then enter the rapids of St. Mary. Vemess, on the south side of the St. Lawrence, sixteen miles from the city,' is a place of considerable resort on account of the springs. At William Henry, or the Three Rivers, one hundred and ten miles from Montreal, the St Lawrence is divided by two small islands into three branches, at the mouth of the St. Maurice. About fifteen miles up this river, are the Falls of Shawennegame, of one hundred and twenty-five feet perpendicular descent. Seven miles below the Three Rivers, are, Richelieu Rapids; the river is no* mile wide, and rushes with great velocity. We are now approaching the Gibraltar of America. The towers and lofty spires of this famed city, situated on a soHd rock three hundi'ed and fifty feet high, bursts upon the view. Cape Diamond, the Plains of Abraham one and a half miles from Quebec, Point Levi on a high, precipitous rock to thd right — and here we are at last Is situated oii a lilgli point of land, formed by tlio coiitlucnco of tbe St. Lawrence and St. Cliarles. Tlio city is divided into two portion!, called the upper and lower towns. The npper pait, the im])rcgnaltle fortress, is reached by five gates ; on the side toward the St. Lawrence thei'e is only one way to enter the city, and tliat is tlirough Prescott gate; through th's gate the commercial transactions of the city are carried on. Pal:ice gate leads to the Ashley Barracks; St. Louis gate opens to the plains of Abraham, where Wolfe and ^Montgomery fell. If we have time we Avill visit the catholic church; it is open at all hours of the day. Among the pictures are, the Confession ; the apostle Paul in his extatic vision; the Saviour ministered unto by the angels; the flight of Joseph and Mary; the Picdeemer and the cross; the nativity of Christ; the Saviour outraged by the soldiers; and the day of Pentecost. The monument erected to the memory of V/olfe and Montcalm, sixty-eight feet higli, v>-ith two Latin inscriptions, luis its attractions. The nunnery and church occupy a space of eight acres, inclosed by a high wall of stone; the inmates are, one superior, foity-tive aspirants, and nine novices; they are more strict than any other con» :nt in Canada. Persons of high distinction only, are permitted to exrmirio the domestic arrangements of this place; but on application to the Chaplain, strangers generally get p«i-mission. There are the paintings of some of the popes; the birth of Emmanuel; the Saviour showing his heart to the religeuses; the Saviour taken down from the cross; a carero of Christians captured by the Algerines; Lewis XIII king of France. Chapel of the Hotel Dieu. In the convent the sisterhood reside — one superior, thirty-five religieuses, four novices, and one postulate — every thing in order. But we must not dwell long here; we have other scones to \lsit, then hasten back to Montreal and Saratoga. Falls of Montmorenci ai-e eight miles from Quebec — a good caniiigc-road and delightful ride; pei-pendicular height of the Falls two hundred and forty feet; width, one hundred. They are beautiful and grand, impressing the mind with sentiments of awe and sublimity. When viewed from below, this mighty cascade is resplendent with all that can be realized, by the river pouring its angi-y waters, into the dai-k, deep and gloomy precipice. No part of these Falls, however, are as gi-and, sublime or terrific, as the Center Fall, or Cave of the Winds at Niagara; after having viewed them from the upper window of the mill, we cross the bridge, and passing along under the brow of a high hill, we are suddenly directly in front of the whole cataract. Here^. in trio opinion of tlio wnter, is decidedly tlio best view wo bavo o^ tbis wonderful fall. From tbo top of tbis bill, Quebec, witb its lofty towers, foitlfications, sblpping, tbe St. Lawrence rolling toward tbo ocean, Point Levi, Angel Garden, and many otber points of interest are to bo seen. Tbrco bundred and sixty miles below Quebec, at tbo nioutb of tbo St. Lawrence, tbo river is one bundred and fifteen miles wide, pouring its waters into tlio Gulf of SL Lawrence, (tbree bundred and fifty miles long, and one bundi'ed and fifty broad,) by tbreo diilerent outlets. On returning to Quebec, we will pass tbo Loretto Indian Villtige — tbe distance is about tbe same. We will now step on boaid tbe morning boat, wbich "will land us in Montreal in tbe evenin<x. Tbo St. Lawrence Ilall is considered tbo best in tbe city ; after refresbment and sleep, we will start in tbe morning for Saratoga. Tbe distances are aa follows : At La Pr; airie, nine miles from Montreal, wo leave tlie steamboat, and step aboard tlio cars for St. Johns ; distance, fourteen miles. This is quite a thriving, but a small place; it is the terminus of the steambout navigation on the northern bounds of Lako Chaiiiplain ; a \ci"y important point in tho French and i-evolul ionary Avars; population about 1500. Lake Ciiamflaix. The hno between Vermont and Xew York passes through the center of this lake; it is one hundred and forty-one miles long, and fifteen broad. At Mount Lidependenco, twenty-four miles from Whitehall, there is scarcely room to tui-n tho boat, tho lake bdng narrowed down to a small river. The ruins of the old forts at Ticonderoga and Crown Point are distinctly to bo seen. Isle Aux Koix, fourteen miles from St. Johns, as a military post, has alternately been in the possession of the French, the English and the Americans, As of logs. Rouse's Point is on the outlet of Lake Champlain, ten miles from Isle Aux Noix. It is a strongly foilificd j)laco, but, according to an agrecmeni of the British and American commissionoi's, to establish the boundary lino between Maine and Canada this place belongs to the British. passes through Mount Pelica. Distance from Ogdcnsburg, on the Rircr St. Lawrence to Boston, fia the Wbife MjtitiL!. i is four hundred aai feu r\'<\, .\ foHci^s: Distuice from Ogdenslnirjr, on tho St. Lawrence, to Boston, via Burlington, Kutlaud, Bellows FaUs, (fee, is thrco hundred and ninety-tbreo miles, aa follows : On tho northern route to Boston from BurK-igton, travelers wishing to visit tho White Mountains leav« at the White River Junction. Daily stages run to the foot of the White Mountains; distant forty miles. When these lofly piles, rearing their majestic heads far above the clouds, fii-st burst upon th« bewildered gaze of the traveler, the effect is perfectly overpowering; ho feels that language is but a poor vehicle to convey the emotions of awe, grandeur and sublimity that fill his soul, and lie sinks back upon himself amid the immensity of God's works. There is no place, perhaps, where ""the mind is more completely bewildered, in endeavoring to grasp at th« illimitable landscape that is presented to his view. They are the loftiest in America except the Rocky Mountains. to tho power of human vision. Having made this short digression from the correct route to Saratoga, -sve will return and commeuco our travels from Rouse's Point. Tlie villan;e of Plattsuurg is on tho Avest sido of Lako Cham})lain, at tho mouth of tho Saranac River, twenty -seven miles from Piouse's Point. It is memorable for the celebr.ated victories achieved in front of tho tower between the British and American forces both on laud and water. Commodore McDonongh and Macomb, (Americans,) gained a complete triumph over George Provost and Commodore Downie, (British,) in tho war of 1 8 1 2. Tlie Americans were at anchor in the bay, and awaited, in awful suspense, the arrival of tiie British fleet, which sooon hove in sight. On the morning of the 11th of September, 1814, the roar of a single cannon came booming ever tho waters; this was tha '4U'i\i\\ for a fV(Mioi;il attack on land and water, and tlii5 hcots were soon comyiiiin-lcd in sad, terrillc htrif<3, Tlie number of British eiig:i;;(id under 8ir Georgo Provost was 14,000; of the Americans under Geneial Macoml), only oOOO; but, Spartan-liko, (ivcry American was determined to die b_^ Lis colors, ratiier tliati surrender, and tlio stripes and the tiars waved in triumpli over the heads of the free and the biave. The loss of the Lriti.sh was 2500 men, besides bajxgago and ammuuitiou; that of the Americans coi].sideia]>Iy less. EuKLiNGTOX, as ii diverging point of the railroads, is situated on tho east side of Lako Cliamjtlain, twenty-live miles southerly from Piattsbiirg. This IS a fine New England vill.ijr * which has its attractions to tho visitor seeino: it for the first time. From ]]urliiigton to Whitehall is seventy-five miles — the terminus of r.teamboat na\igation on tho southern point of Lako Champlain, sevonty-threo miles north of Albany. From "Whitehall to Saratoga, (railroad,) thirty-nine miles. Visitors wishing to pjuss through L.'ike Georgo, on their way to the Springs, stop at Ticonderoga ; this route will bo described in another place; at present we will pursue our course direct; cars leave AVh it chall every morning on the an-ival of tho Lake Champlain boat", and reach Saiatoga Springs in time for dinner. Saratoga Springs, This place of fitohionable resoii, from all parts of the world, has attained great celebrity from the medicinal properties of its waters. They he m 43 degrees 10 minutes north latitude, and 73 1 degrees west longitude from Washington, on a line directly east from ' Niagara Falls. The Springs immediately in the vicinity of Saratoga, are twelve in number; those most frequented are the Congress, the Iodine or Waltien, Putnam's Congress, the Monroe, the Hamilton, the Flat Rock, the High Eock, the Columbian and the Washington. A new spring, possessing, it is said, great medicinal properties, was discovered in 1339; it is of a brackish taste, and not as pleasant as many others. It is at the south end of the village; it was seen issuing from the crevice'of a rock about fifteen feet from its present location. Here it boiled up, and its water?, sparkling in the sunbeam, continued to flow, until art V3gan to lay its plastic hand upon the works of nature, in the shape of improvements; the spring retired back upon its fountain, and nearly ceased to flow ; but collecting its energies, it soon broke out again near where it is now. There is a deep tube sunk into this spring, fifteen feet long, which efiectually screens it from sand, sediment and fresh water that might be oozing through the rocks. Doctor Steel, one of the most celebrated chemists of the age, says, "a gallon of water which he analyzed, contained the following substances: tiz, chloride of sodium, three hundred and eighty -five grains ; hydriodate of soda, thirty-one and a half grains ; bicarbonate of soda, nearly nine grains; bicarbonate of magneaia, nearly ninety-six grains ; carbonate of lime, a little more than ninety-eight grains ; carbonate of iron, upwards of five grains; silex, one and i half grains; carbonic acid gas, Chree hundred and f^.even cubic inches; atmospheric air, seven cubic inches." Perhaps there is no spot on the globe where we can se« a greater diversity of character, than at the Congress Spring; the halt, the gay, the giddy, the blind, the aged, the decrepit and the beautiful are crowding on to this Siloam, expecting to lie healed from all their infirmitiefv of gratify the eye ly seeing the fashion of the four quarters of the globe. Very few persons, I think, relish this water when first tasted, but habit familiarizes, and we soon become fond of it. The Iodine was discorered in 1838, near the High Rock Spring. The water is remarkably pure, sparkling and j)ungent^ but r~ imuch less of iron. Professor Emerson says, "one g 1 of this water contains muriate of soda, one Imndred and thirty-seven grains; carbonate of lime, twenty-six grains ; carbonate of iron, one grain ; carbonate of magnesia, seventy-five grains; carbonate of soda, two grains; hydriodate of soda, or iodine, three and a half grains; carbonic acid gas, three hundred and thirty cubic inches; atmospheric air, four inches. Though this spring has not been much visited until of late, yet it bids fair to equal many of its neighbors, and doubtless will hold a high rank among the fountains of health. A few rods from this is a very strong sulphur spring, which is used extensively in some cases. Putnam's Congress is near the Hamilton Spring. Here its healing watere flowed for years unnoticed, but it is now popular and much frequented. The High Rock Spring is nearly three-fourths of a mile north of the Congress. The rock out of which this spring boils is a curiosity; nine feet diameter, five high. The particles of sand, formed by some chemical process, were once raised by the action of the water below, and instantly flowed over the top. The aperture is nine inches. The water does not flow over the summit as formerly, but rises within two feet of the top. This may be attributable to the fact, that it has found a passage between the decayed rock, and the loose earth out of which it was formed. Between the Iodine in the upper village, and the Washington in the lower, are most of the mineral spnngs in which this place abounds. No chemist, as yet, has been enabled to discover ihe causes which have produced these wonderful results. Some say it is the i-esiilt ot some " great laboratory," but where this miglity worki^hop is, or what is its process of working, is a mystery. It will be unnecessary to enlarge upon the many and convenient bathing-houses erected at neai-ly all these s])rings, for the convenience and heallli of the visiter. It is said by those whose opinion is entitled to respect, that the properties of the waters, both of Saratoga and Ballston Spa, are noarl}'' the same, varying only as to the quantities of the different articles held in solution. They are called by the chemists acidulous saline, and acidulous chalybeate; of tb : former, are the Congress, Iodine, Monroe, Putnam's Congress, the Hamilton and High Rock at Saratoga; and of the latter, are the Columbian, Flat Rock, and Washington' at Saratoga, and the Old Spring, and Sans Souci at Ballston. The waters, all to a greater or less extent, contain muriate of soda, hydriodate of soda, carbonate of soda, carbonate of lime, carbonate of magnesia, oxide of iron, and some of them a small quantity of silica and alumina. Great quantities of carbonic acid gas are contained in them, giving to them their sparkling and lively appearance. The late Doctor Steel, in his geological report of the county of Saratoga, published a few years since, says,, that "the temperature of the waters, in all these wells, is nearly the same, ranging from 48 to 53 degrees on Fahrenheit's scale ; and they suffer no sensible alteration from any variation in the temperature of the atmosphere; neither do the variations of the seasons appear to have much effect on the quantity of water produced, "The watera are remarkably limpid, and when first dipped, sparkle with all the life of goo champagne. The saline waters bear bottling very well, particularly the Congress, immense quantities of which are put up in this way, and transported to various parts of the world; not, however, without a considerable loss of its gaseous property, which renders its taste much more insipid than when drank at the well. The chalybeate water is also put up in bottles for transportation, but a very trifling loss of its gas produces an immediate precipitation of its iron ; and hence this water, when it has been bottlod for some time, frequently becomes turbid, and finally loses every trace of ion ; this substance fixing itself to the walls of the bottle. 'The most prominent and perceptible eflfecta of these waters, when taken into the stomach, are cathartic, diuretic and tonic. They are much used in h great variety of coraplnints; but the diseases in which they are most efficacious are jaundice and bilious affections generally, dyspepsia, habitual costiveness, hypochondriacal complaints, depraved appetite, calculous and enphritic complaints, phagedenic or ill-conditioned ulcers, cutaneous eruptions, chronio rheumatism, some species or states of gout, some species of dropsy, scrofula, paralysis, scorbutic affections and old scorbutic ulcers, amenorrhea, dysmenorrhea and clorosis. In phthisis, and indeed all other pulmonary affections arising from primary diseases of the lungs, the waters are manifestly injurious, and evidently tend to increase the violence of the disease, "Much interest has been excited on the subject of the source of these singular waters; but no researches have as yet unfolded the mystery. The large proportion of common salt found among their constituent properties may be accounted for, without much difficTi^ty — all the salt springs of Europe, as well as those of America, being found in geological situations exactly corresponding to these; but tbd production of ^be unexampled quantity of carboni acid gas, the medium through which the other articles are held in solution, is yet, and probably will remain a subject of mere speculation. The low and regular temperature of the water seems to forbid the idea that it is the effect of subterranean heat, as many have supposed, and the total absence of any' mineral acid, excepting the muriatic, which is combined with soda, does away the possibility of ita being the effect of any combination of that kind. Its production is therefore truly unaccountable." It would be unnecessary, perhaps, to enter into detail of the public houses ; tlio visitor will at once see that they are not surpassed by any in the United States. Among the principal are the Congress Hall, Union Hall, Pavilion, United States. Among the boarding houses, on a less extensive scale, are the Adelphi, Columbian Hotel, "Washington Hall, Railroad House, Prospect Hall, Highland HalL Price of board at the first class houses is from foil, to twelve and fifteen dollars per week. w i Amusements. Fishing in a small pond kiout two miles from the village is resorted to by ««no; trout in considerable quantities are taken. Oth^m prefer a sail on the lake four miles from the fc^ii.ij.^s; nine miles long, three broad. Sail-boats 0/ af»^ry descffpUon, are fitted up in good style for parti ♦» of pleasure. Bemus' Heights^ eight miles fnnn the lake, will ever bo sacred in the memory of Amoricaas, as the phice where General liurgoyno Burron(Jered his entire force to General Gates, in the revolutionary contest, OctoLer iVth, 1117. The two actions that preceded this surrender were fought on the 19th of September of Lh-^ °ame year. Cotillion parties, in all the large houses at Saratoga, are attended almost every night. Elegant carriages will convey parties to any point of interest, at a moderate price. : It is now time to return to Lake Georfje. Some of our party we left at Ticonderoga; peihaps we may meet them. Lake George is twenty-five mile^ from Saratoga. The water of this lake is remarkably transparent, and it is said tliat a sixpence can bo seen at a depth of twenty feet. The Catholics, we are told, carry theso waters to all parts of the world, for religious purposes. The waters of Lake George are discharged into Lake Champlain, at Ticonderoga, by a small river, which, in two miles, falls one hundred and eighty feet. Large quantities of most excellent fish are taken fi-om . its watere ; such as trout, bass, <kc. It is dotted with small islands, comporting in number, it is believed by some, with the days of the year. Diamond Island once contained a fortification. There is a beautiful summer-house on Tea Island, for the amusement of parties of j>leasure, which is seen from the head of the lake ; the best view of the lake, in our opinion, is near the remains of old Fort George. Here, General Burgoyne made a depot of bis military stores for some time in the revolutionary war. Here are our friends we left at Ticonderoga about a week since They have enjoyed fine sport upon the waters of this limpid lake. There w a small, but very neat steamer which pli<'8 daily from the head of Lake George, (Caldwell,) to the foot, connecting ;vith the steamers on Lake Champlain. From where the boat lands to Ticondeniga is three miles. Carriages are always in readiness. The boat returns every evening. Length of the lake is thirty-six miles. Fourteen miles from Caldwell, is Tongue Mountain. The Narrows commence here ; about seven miles long, one and a half miles wide Five hundred and fifty feet of line have been let down without finding bottom. Black Mountain, half way down the lake, is on the east side. It is ascertained by actual measurement to be 2200 feet high. A short distance from this is an exhibition of mountain sceneiy, unsui-passed on this continent. The rolling appearance of the mountain — the deep and almost impenetrable caverns that yawn out before you at every step; the wild, the beautiful and terrific grandeur of th6 whole place, combine to fill the mind with solemn awe and admiration. Solitude holds her empire here, undistui bed by the convulsions that agitate the world ; the fall of empires or tliG ruin of kinirdoins is alike iiulicedcd and uuknowii. Siibbatli-diiy Point is twenty-four miles from the hoad of the lake, on the west side. During the I'rencli war, about three hundred and fifty Englisli landed hero on Sabbath morning. They were iTi.s(antly surrounded by the Indians and every soul to a man, i)erished by the tomahawk and scalping knife — hence the name. In three miles we pjLss a small island called the Scotch Jionnet; three and a half miles below, on the west shore, we approach the city of Hague, composed of two houses and a saw-mill; this is the widest part of the lake, viz.,' four miles. Rogers' Slide is three miles further down; here. Colonel Rogci-s, an inveterate foe to the Indians in the French war, was forced by tlie savages, in the winter, over a smooth rock two hundred feet high, on an angle of thirty degi-ees. He slid down with the velocity of light, and landed safely on the ice below. Anthony's Nose opposite, by drawing a little on the imagination, will be found similar to one of the same name on the Hudson. Prisonei-s' Island is two miles further; prisoners were confined here during the French war. Lord Howe's Point is directly west ; ho landed upon thia spot but a short time before the battle at Ticonderoga, at which he was killed. He was brother to Lord How^e, who commanded the British forces at ^Philadelphia, in tie revolutionary war. One mile landing is TicoNDEROOA, the far-famed place, memorable for its thousand daring exploits, and bold achievements. Mount Indepetidunce, with '\\a ruins, is here. Mount Defiance, seven hundred and fifty feet high, looks down in frowning contempt upon the world below. Here General Burgoyne lodged his artillery in 1777, and here the Americans were compelled to evacuate Ticonderoga. Many of the old walls, though mouldering in gloomy silence, are still to be seen ; the maijazines of this oKl fort are nearly entire; the walls, two hundred feet above the level of Lake Champlain, are still standing. A subterraneous passage leads from the south-west corner of the fort, about thirty rods long, through which the celel)rat(>d Colonel Allen made his way, and took a British oflicer while in bed; when asked by what authority he did it, he re))lied, "by the authority of the cHiat Jehovah and the Continental Connrress." There aie several old foils and fortifications in this vicinity still to be seen; the walls of one near the lake are sixty feet high. As early as 1758, General Aborcronibie, with two thousand men, attacked Ticonderoga with great skill and bravery, but wns repulsed with the loss of his entire araiy. The Fiench abandoned this position to the En;j;lisb in 1759. Colonel Ethan Allon, whose indomitable cournge has nevor been surpassed since the days of Rome, took Ticonderoga by storm in 1775. In 1777 it was abandoned. General Burgoyne pursued the American foi-ce as far as Whitehall and to ' Fort Ann, which soon resulted in the surrender of his entire army to General Gates — one of the most glorious epochs in the revolutionary struggle, giving to the colonies a foothold, a permanence and a standing, which never for a moment has been shaken. The banner was thrown to the breeze, and waves in triumph over the heads of the 1 oe and the brave. "We must now leave our fnends and return to the Falls to accompany another party via Lake Ontario, (American side.) We prefer the route from Saratoga, via Auburn, Geneva, Canandaigua, Batavia» BufFjilo, (fee, because it is the most expeditious. Distance from the Springs to the Falls by cars is three hundred and twenty-nine miles. By this route we reach Niagara in twenty-two hours. As we pass we notice Ballston Spa, seven miles from Saratoga ; the waters, according to Doctor Steel, are nearly similar to those of Saratoga. The first spring discovered is in a valley, surrouuded by sandhills, on a branch of Kayaderoseras creek, inclosed by an iron railing; New Washington Spring is but a few rods distant; the Sans Souci Spring is the most frequented. The Wasliington Foiintaiu flowed over the surface for mary years, but iu ) S21 disappeared entii'cly. Low's Spring, Park bj^i ing, and several othera in the n'^ighborhuod, ^\ere much visited in foiTQcr yeai-s, but hitterly are measurably deserted. Schenectady, fourteen miles iroin Albany, and twenty-two from Saratoga, lies on the Llohawk liivcr. It was destroyed by the Indians iu IGOOj and nearly all of its inhabitants penshed by tho tomahawk ; Union collegG is well endowed ; popuhvtion, 7000. Amsterdam, sixteen miles west, on the north side of tho Mohawk; tho Erie Canjd passes througa this village. Fonda, ten miles from Amsi'^rdam, is a small place. Johnstown, four miles north, was tho former residence of Sir William Johnson. the Catskill Mountains. Fort Plain, three miles further, was originally settled by Germans, who, like their neighbors, suffered much in the revolutionary war. Little Falls, seventeen miles further; the Erie canal and Buflfalo railroad, at an immense expense, pass tlie south part of the ^'illage ; a place of considerable commerce from the Erie canal and its hydi-aulic power. The mountain scenery is grand and sublime. Herkimer is seven miles from Little Falls, on the West Canada creek, on which the far-famed Trenton Falls are situated. The creek enters the Mohawk about half a mile west of the villaofe. Utica, fourteen miles from Herkimer and fifteen from Trenton Falls, is on the south side of the Mohawk. No city in the interior of New York possesses greater facilities for commerce than Utica. It is located on the site of old Fort Schuyler; population 15,000; its long line of canal-boats, together with the seven trains of cars that pass through the place from the west, render it a place of great importance. Trenton Falls, as has been remai'ked, are fifteen miles from Utica; they are on the West Canada creel:, twenty-two miles from its confluence with the Moh-iwk River at Herkimer. Visitors usually prefer taking carriages at Utica; going and returning will occupy nearly a day. There is no such terrific grandeur and awful sublimity here as at Niagara ; yet they are beautiful, and in many respects Bublime ; their effect upon the mind of the beholder is deeply impressive, and he long retair": the vivid impressions enstamped upon his r^cmory. The tourist ought, by all means, to visit them; they must be seen before they can be appreciated. one hundred; width of ravine at the top, two hundred ; depth of creek below the Falls, one hundred. A dark, heavy forest hnngs in moody silence ^ver the ravine, shuLtiug out the view until you /each the very verge. The falls are six in number, as follows: first, the one on the Black liiver road; second, the upper, ihree-fouiths of a mile below the cascades; third, the mill-dam; fourth, the High Fall; fifth, Shermans; sixth, Canard's. Descent of Falls : upper, twenty feet ; cascades, with two pitche* And rapids, nineteen feet; the mill-dam, the second within the ravine, fourteen feet ; width of stream at tlie top, one hundred and eighty feet. Of the high falls there are three. Des;!ent of firet, forty-eight feet; second, eleven feet; third, thirty -seven feet. These three, including the rapids above, make a descent of one hundred ten and one-half feet Sherman's Fall descends thirty-three when the creek is low, and thirty-seven and thirty-nine when high; tiiis, unlike Niagara, rises when the rains fall, but is subject to fall many feet in droughts; the height of Canard's Fall is six feet. The entire descent of the falls, rapids included, is estimated to be three hundred and eighty-seven feet, in less than four and one-half miles. I The best time to visit the Falls is in July or Au gust, or when the water is low ; you can then pass round Sherman's Stairway with perfect safety to the head of tho race-way. At tlio hotel there are two paths : ono leading to the bottom of tho ravine, tho other to the High Falls; the former is generally preferred. At tho foot of the stairway pass up the stream; then by a narrow pathway to Sherman's Falls ; in a few moments you reach the High Fall From these falls to tho upper end of the race-way, above the cascades, the way is easy when the stream is low ; but from tlicnco upward is more difficult. Petrifactions and organic remains may be found imbedded in tho rocks in the ravine. They lie flat in tho laminss; "their contours," says a celebrated geologist, "and component parts, usually being hide distorted from their original shape and dimensions. Sometimes there is a defect occasioned in ^heir transition from tho animal to tho stony or fussil state; but, in most instances, all their pr 3 are so completely defined that not only the order, but the genrra and species may bo recognized. Their exteriors are commonly glossy, often very smooth, and ordina -ily of a dark color, being transformed into stone, and constitute integral parta of tho rocks which envelop them. To any ono who has devoted any time to the subject, it will appear that their prototypes lived and died on tho spot, and that the rocks ia which they are entombed, are of subsequent formation. A word to the ladies before w© leave: good calf-skin boote or shoes are decidedly prefera blc, both as to health and for convenience ; the finest pair of cloth shoes would bo ruined in a single excursion over these rocks. We now return to Utica. On our way west, the first place we will notice is Syracuse, fifty-tliree miles. Perhaps there are no works on the globe, where as much salt is manufactured as in the vicinity of Syracuse and Salina. Four hundred and fifty acres are covered with vata for solar evaporation ; the roofs drawn over and removed at pleasure. Three times in the summer the salt is taken out and barreled for market; forty gallons make more than a bushel of pure salt. There are one hundred and eighty-five works for boiling within five or six njiles. The state of New York owns the entire works, which yield a great revenue. The Springs will iasi, probably, while the world stands. Nearly three millions of bnshels are manufactured yearly. From Syracuse to Oswego, on Lake Ontario, is thirty-five miles, by railroad; here steamors take passengers down the lake to Montreal, or up to Lewiston, sevon mil'^s from Niagara; but we will keep the railroad to tlia Falls, via Buffalo. Auburn is twenty-tix milec from Syracuse. It is situated on the Owasco croel, and affords great hydraulic power, which is cxter-svely used. The stata prison is the heiX ^'.^jk^U^i ioijt Itution of the kind in the United Staiy.a, ^ihe fvrrzge number of y earlycon victs is befiv></ ^^erM and eigl/i bandred; popnlati'on, 10,000. The best time to see the prioneri is before breakfast; one of the keepers will accompany you for a mere trifle. The next place of much importance is Geneva, twenty-three miles from Auburn, situated on the north end of a lake of the same name, thirty-seven miles long, and about four wide ; salmon trout are taken from its waters; it never freezes. It was upon the waters of this lake, that the celebrated Jemima Wilkinson (who pretended she was the Saviour,) made her followers believe she could walk on the water if they had ) aith. She stepped from her carriage into the element, about ankle deep ; then turning suddenly to the multitude she again inquired if tbey had faith that she could pass over. They answered in the affirmative. She immediately returned to her carriage, declaring, "as they believed in her power, it was unnecessary to display it; " thus ended the farce. Travelers from the west frequently take a steamboat to the head of the lake, thirtyseven miles, connecting with the New York and Erie Railroad. Canandaigtja is sixteen miles from Geneva, on an outlet of the Canandaigua Lake. It is one of the most beautifullv located villagjes in the state. Rochester, twenty-eight miles farther west, lies on both sides of the Genesee River. Tha Erie canal and Buffalo railroad cross the river at place, on the most substantial works in America. There are twenty-five flouring mills in the city, one hundred atid twenty-live run of stones, making 5500 barrels of flour, and consuming 22,000 brishels of wheat in every twenty-four hours. There are six falls in the river, the highest of vvliich, just below the bridge, is ninety-seven feet perpendicular. The celebrated Sam Patch, after he had made two successful jumps at Niagara, took his last and fatal leap here in 1829. Two and a half miles below the citv, travelers can take steauiers for the Fulls of Niagara, or down the lake to Montreal, &c. A railroad is nearly com})kted in a direct line to Niagara, crossing the river two hundred and thirty feet above one of the maddest streanis on the globe. ButValo has been mentioned in another place. If our friends are ready, wo will now start for our northern tour to Montreal, via Lake Ontario (American side,) commencing* at Fort Niagara, at the mouth of Niagara River, fourteen miles below the Falls; intermediate \A'aq,q& and distances have already been described. The first place the boat touclics at after leaving Furt Kiniicara is Charlottesville, at tlie moutli of the Genesee Ri\'cv, seventy-four miles. It is a port of entry; has a light-house. Government has expended a good deal of money to improve the navigation. The river is navigable four miles further, to Carthage^ thence two miles to Rochester. Passengers arc conveyed to the city by railroad carriages without delay. GitEAT SoDTJs Bay is twenty-eight miles from Oswego. iThis bay, with its coves and points, is about fifteen miles in circumference. Oswego is sixty-three miles from Rochester, and is quite an important place. Cars leave Oswego for Syracuse every day, on the arrival of the lake boats ; distance, thirty-five miles. Sackett's IIaudor is forty-four miles from Oswego. The government made great efforts to put this place in a state of defense during the hist war. The barracks are still standing; two forts are nearly in ruins. A large ship of war was commenced, but tlie materials have decayed, and it never can b« finished. Cape Vincent, twenty miles fro.n Sackett's Harbor. Kingston, in Upper Canada, is on tlie opposite side of the lake; Grand Island between; Morristown, fifty miles further. The river here is one and a quarter miles wide ; opposite, on the Can ada side, is Brockville. OoDENSBURO, American sid^ is twelve miles further, on the Oswegatchie River; a fine, flourishing village; cars, on the arrival of the boats leave for Rouse's Point on Lake Champlain; distance, one hundred and eighteen miles; from Rouse's Point to Burlington, forty. At Burlington, on the east side of Lake Champlain, there are two railroad routes to Boston, which have already been described. Boats down the river from Ogdensburg, generally pass over to Prescott. There is also an express line of steaxners from Lewiston through the center of the lake to Montreal. The route to Boston, as mentioned in another place, commences at Burlington, in the state of Vermont, on the east side of Lake Champlain. Montpelier is the capital of the state, thirtyeight miles from Burlington. Lofty mountains, lifting their bleak and towering heads to the clouds, surround the city on all sides. It contains thiee thousand inhabitants, who are enterprising, industrious and happy. It wm at this place that the Green Mountain Boys rendevouscd, who were so annoying, and fought Burgoyne with such indomitiible From Burlington to Concord, the capital of New Hampshire, is two hundred and two miles. It lies on the Merrimack River, which is navigable for large boats to Chelmsford. From Concord to Lowell is forty-eight miles. It is on the Merrimack River. Perhaps there is no place on the globe, none in the United States certainly, where there is as much capital invested in manufactures as at Lowell. The following gives some idea of the business done : amount of capital, $10,000,000 If the yards manufactured in one year, were all united, they would reach 16,400 miles. From Lowell to Boston is twenty-five miles. Boston 35 Rutland is on the west side of the Green Mountains, three miles distant. It is not suri^assed for beauty of location by any village in the state. Bellow's Falls lies on tlio west bank of tbe Connecticut River ; tlie length of the rapids is about three-fourths of a mile; descent of tho river in this distance, fifty feet; at the toll-bridge is tho best view; t^ o waters rush under tho bridge with gi'eat power, in their wildest fury. Is situated at the foot of Massachusetts Bay, on 'a peninsula two miles long and one broad. It derived its name from a clergyman who emigrated from Boston, England. The monument on Bunker Hill, to perpetuate the memory and heroic virtues of the dcatl, IS fifty foot dianKitor, two liuiKlrod and t\ycnty high. Whou complolod, it Asill jutvio in aplondor, ntiy of a siinilar charactor on this continent. Tho do Lafayotto assistod in tho ceronionios. The nujiibor of Briti.sh onnjaixod in tlio action of Bunker Hill Avas ostiniatod at JJOOO; Anioricans, 1500. Tho Ihitish lost, in killed and wounded, 1050; tho Americans, four hundred and liCty. Hero Gencnd Warren, tho scln^lar, the gentleman, fell in tho commencement of tho action. The ha"^>or is spacious and commamllnnr; tho entrance is exceedingly narrow, scarcely admitting two ships abre:ist. It is so strongly fortified, that any hostile ship in attemptr ing to land, would bo blown out of tho water; population, 100,000. Boston uill bo retained in tho recollections of Americans, -while virtue, liberty and })atriotism remain. Tho hallowed associations, that linger aroimd this sacred spot — tho glittering steel of England's best sons, as they marched with a firm and steady tread to tho attack on Bunker Hill ; tho flames of Charlostown, as they rolled in red suigos to the sky; tho awful stillness of tho heroic band in the little foii precursory to tho coming storm; tho lieights crowded with anxious spectators, witnessing in breathless silence the doubtful contest; tho memory of those wlio fell, more durable than the monuments of brass or marble; the roar of the artillery from the bay — all united to make it a scene awfully grand and terrific, impossible for the most vivid imagination to portray. The British were permitted to approach within less than a hundred yards of the fort ; not a shot from the Americans, not a muscle moved — the silence of death held its empire over the little fortress ; but in an instant the storm burst ; flash sucoeediiig flash, the iion tempest sweeps; heaping man; horse and car, in one undistinguished ruin; twice, the peals of musketry and the saber's ch'ish drove the enemy back ; but at last they succeeded in gaining the heighl- after the ammunition was all exhausted, and the cry rang through the fort, "powder! powder! a world for powder ! " "Let it not be supposed that our object is to perpetuate national hostility, or even to cherish a mere military spirit It ia higher, purer, nobler. We consecrate our work tc the spirit of National Independence, and we wish that thj light of peace may rest upon it forever. We rear a memorial of our oonviction of that uumeasured benefit T^hich has been conferred on oiir land, and of the happy influences vfh'ick have been produced by the same events, on the general interests of mankind. We come, as Americana, to mark a spot ^vhich must be forever dear to us and posterity. We wish, that whosoever, in all coming lime, shall turn his eye hither, may beliold that the place is not undistinguished where the first great battle of the revolution was fought. We wish, that this structure may proclaim the magnitude and importance of that event to every class and every age. We wish, that infancy may learn the purjDose of its erection from maternal lips, and withered age may behold it, and be solaced by the recollections Avhich it suo-orests. We wish, that labor may look up here, and be proud in the midst of its toil. We wish, that, in those days of disaster, which, as they come upon all nations, must be expected to come upon us also, desponding patriotism may turn its eye hither, and be assured that the foundations of our national power still stand strong. We wish, that this column, rising toward heaven among the pointed spires of so many temples dedicated to God, may contribute also to produce, in all minds, a pious feeling of dependence ai 1 gratitude. We wish, finally, that the last object on the sight of him who loaves his native shore, jmd the first to ghdden his wlio revisits it, miiy bo something v.liieli sLall ro mind liim of tlie liberty and glory of his country Let it rise, till it meets the sun in his coming ; let the earliest light of morning gild it, and parting day linger and i)lay upon its summit." On the morning of July 19th, 1853, a great excitement was created by the discovery of a man on a log in the rapids, midway between the main shore and Bath Island, and about forty yards below the bridg'3 which leads to the toll-gato on the island. The circumstances as near as are known of the way ho got there, are those: This man, Avery, and another man, they being in the employ of Mr. Brown, boating sand above the Falls about two miles, got into a boat at ten o'clock at night to cake a pleasure sail. The next morning Mr. Avery was discovered on the log above mentioned, which being reported, called thousands of people to the spot to see the unfortunate man, and to do what thov could to rescue him. In the first place a small tx>at was let down, but it filled with water, and sunk befjre it reached him. By this time a life-boat from Buffalo had reached the spot, and w;i3 lowere I into the stream, which reached the AVERY ON THE LOG. log he was on, passed by abovo it, capsized and sunk, wliicli wss the last of that. The next, a Bniall boat was let down, which reached the spot all right, but the ropo got entangled under the log, and could not bo got loose, so that boat was usedess. Another plan w;i3 tried: a raft was let down to him all rigiit, and he got on it, and the raft was moved toward Bath Island as far as it could be, for the ropes got entangled in the rocks, and stuck fast. Then another boat was let down to him, to take him froni the raft ; but as the boat reached the raft, the water dashed the boat against tlio bow of the raft, which gave it a sudden jog, and Avery not using the means that were prepared for his safety, viz., ropes for him to hold on to, or tie himself with, stood erect on the stern of the raft ; and as the boat struck, he fell off backward, and the rapid water carried liim over the Falls, at about six o'clock P. M., at which time the crowtl, (being about three thousand in number,) left the spot with slow and Bolcum slops for their homes, to think and talk of what had transpired.	35,772	common-pile/pre_1929_books_filtered	cihm_22357	public_library	public_library_1929_dolma-0004.json.gz:2990	https://archive.org/download/cihm_22357/cihm_22357_djvu.txt
57RzohYygBUEKMIC	Meat Cutting and Processing for Food Service	10 Cholesterol Content in Meat What is cholesterol and why do cooks and meat processors need to know more about it? Cholesterol is essential for the structure and function of every cell in the body. Cholesterol is a waxy, fat-like substance that is found in all cells of the body and similarly in the meat of animals. The body makes all of the cholesterol it needs to function normally, but additional cholesterol enters the body through the consumption of animal products such as meat, eggs, and dairy. There are two types of cholesterol found in the body. High-density lipoprotein (HDL) cholesterol is commonly called “good” cholesterol, as opposed to low-density-lipoprotein (LDL) cholesterol (“bad” cholesterol). LDL and HDL travel in the bloodstream, carrying cholesterol to wherever it needs to go within the body. HDL carries cholesterol back to the liver, where the body can process and remove it, while LDL leaves small traces of cholesterol on the walls of arteries as it travels. Too much cholesterol, high levels of LDL in particular, may cause atherosclerosis, a condition in which plaque (which is made up of cholesterol, fat, calcium, and other substances found in the blood) is deposited in artery walls, blocking the blood flow to vital organs, which can result in high blood pressure or stroke. Cholesterol levels are measured by the concentration of HDL and LDL in the blood. A blood test will identify the amount of HDL, LDL, and triglycerides (the most common type of fat found in the body) present in the blood. A total cholesterol value is calculated by adding the amount of HDL, LDL, and 20% of the triglycerides together. This is represented in either micromoles per litre (mmol/L) or milligrams per deciliter (mg/dL). In Canada, physicians use mmol/L, while in the United States, mg/dL is more common. A total cholesterol level of 5.2 mmol/L (200 mg/dL) or below is recommended for an adult, with a level of 4.65 mmol/L (180 mg/dL) considered optimal. People with higher than recommended cholesterol levels are usually advised to be on a low cholesterol diet; therefore, we need to know more about which foods have less cholesterol so that we can cater to everyone’s dietary needs. Table 5 lists some high-, moderate-, and low-cholesterol foods that are commonly used in restaurant kitchens and meat operations. \| High-Cholesterol Foods \| mg per 100 grams \| \| Butter \| 250 \| \| Clarified butter \| 256 \| \| Cream cheese \| 110 \| \| Whole eggs \| 372 \| \| Egg yolks \| 1,085 \| \| Heavy whipping cream \| 137 \| \| Light whipping cream \| 111 \| \| Yellow cheese \| 108 \| \| Lamb kidney \| 337 \| \| Pork liver \| 301 \| \| Lobster \| 200 \| \| Oyster \| 206 \| \| Shrimp \| 125 \| \| Roe \| 479 \| \| Crab meat (Alaskan King) \| 127 \| \| Fish oil, menhaden \| 521 \| Table 5 – High-, medium-, and low-cholesterol foods	647	common-pile/pressbooks_filtered	https://ecampusontario.pressbooks.pub/meatcutting/chapter/cholesterol-content-in-meat/	pressbooks	pressbooks-0000.json.gz:13350	https://ecampusontario.pressbooks.pub/meatcutting/chapter/cholesterol-content-in-meat/
E7PiJkAfFRwq6VZ3	A directory of institutions and societies dealing with tuberculosis in the United States and Canada; comp. by Lilian Brandt.	INTRODUCTION This Directory has been prepared with two objects in view. It is designed, first, to serve as a guide to the physicians and friends of consumptives, whether poor or well-to-do, by furnishing accurate information in regard to existing institutions. At the same time an attempt has been made to present a bird's-eye view of all the organized work that is being done in the United States and Canada for the cure and prevention of tuberculosis. While the inclusion of an institution in this volume is in no sense to be taken as a recommendation of it, by either the New York Committee or the National Association, still, on the other hand, the attempt has been made to exclude all sanatoriums of an undesirable character : one, for instance, has been dropped from the list because it advertises a new specialty every few months, although just at present the specialty is tuberculosis; another, because the m.ost prominent feature of the treatment provided is the injection of a serum of secret manufacture; another, because it has displayed such zeal and persistence in advertising its superlative excellences as to remove any possibility of confidence. Several others, it should be added, with which some correspondence has been had, have been excluded for no such reason, but merely because, while they do not refuse to admit consumptives, they make no special provision for the treatment of tuberculosis, and have an insignificant number of such cases among their patients. Boarding houses and hotels without medical supervision or sanatorium regulations have not been included. A reliable list of such as are open to consumptives and can be recommended by a physician would be most useful. The introductory chapters in each section furnish a criterion for judging existing institutions and will in many particulars offer a guide to persons who are planning new ones. In regard to each institution the aim has been to give facts which will enable the physician to form a just estimate of it and which will give the patient and his friends some idea of its character. against leaving home for any place without counting the cost. From California, Colorado, New Mexico, Arizona, and the Carolinas, come protests against the barbarity of physicians who send patients in an advanced stage of consumption far from home and friends, and even from medical advice, with insufficient means to supply the necessaries of life. There is no climate which will avail to cure consumption if the other elements in the treatment are privation, worry, and homesickness. For a consumptive in any stage of the disease to go to a health resort with the idea of supporting himself while he gets well is folly, if not madness. There is always, at such places, an excessive supply of the kind of labor he can offer, and wages are proportionately low. The cost of living, on the other hand, is apt to be much higher than the average. Furthermore, it is necessary that exercise, even in the earliest stages of the disease, should be taken under the direction of a physician. It is useless, in brief, to go to the most favorable climate unless one has the means to meet a year's expenses, including a reserve for emergencies. Hiow far the second object of the Directory has been attained it is difficult to judge. It is believed that the list of institutions exclusively or chiefly for the treatment of tuberculosis, and the list of associations for the prevention of the disease, are practically complete. There may be, however — and it is to be hoped that there are — many omissions of almshouses, hospitals for the insane, and prisons and reformatories, in which consumptives are segregated and given special care. No attempt has been made to show what is done by charitable societies in caring for poor consumptives in their homes, because, although the work itself is extremely important, an account of the variations in method would be somewhat outside the scope of the present volume and a complete inventory would include practically all the relief giving societies in the country. The United Hebrew Charities of New York City may be cited as a conspicuous example of a society which has for several years been devoting special attention to the tuberculosis problem among the families under its care. All of the families in which consumption is the main problem are placed under the care of a special committee. The work of this committee begins with a careful medical examination, on the results of which subsequent action is determined ; treatment in a sanatorium is provided, when this is possible ; when the patient is obHged to remain at home desirable medical treatment is supplied and necessary food ; suitable work is secured for the improved consumptive, frequentlv in the suburbs or in country towns ; transportation is provided when a change of climate is advised ; and in all cases friendly visiting and instruction of the consumptive and his family are prominent features of the treatment. Much can be done for consumptives wdio cannot or will not leave home. For those in the early stages dispensary treatment, accompanied by proper living, may effect a cure, and sometimes it is not even necessary that the patient should stop working. Many of those in whom the disease is farther advanced are unwilling to leave home, and when there is little hope of recovery there is no reason w^hy they should be forced to do so, unless they are a menace to those about them. In all kinds of cases good results have been secured at home by providing suitable medical advice and necessary food and carefully supervising the family life. It may not be possible, in most instances, on account of the advanced stage already reached by the consumptive before the family comes under the care of the society, to effect a permanent cure, but it is always possible to prevent the patient from being a source of danger to others and to teach his family what they should know for their own protection in the future. To point out the conspicuously weak spots in what the French would call our "armament against tuberculosis," would be practically to enumerate the different parts of the armament. For there is no class of institutions, wdth the possible exception of sanatoriums for the well-to-do, of which there is as yet anything approaching a sufficient number. More than a hundred thousand deaths are caused by consumption each year in the United States. The total number of beds for consumptives, in all kinds of institutions, is less than eight thousand, and almost one-third of them are in the state of New York. There is imperative need of free sanatoriums for early cases and of sanatoriums for persons who are able to pay five or six dollars a w^eek. Nor is it desirable that these should be massed in the Adirondacks, Colorado, and the southwest. They should be distributed over the country. In Massachusetts and New York, state sanatoriums are now in operation ; the Rhode Island buildings are completed and will be occupied in 1905 ; New Jersey has secured a site and has appropriated a sufficient amount to erect and equip buildings ; an initial appropriation has been made in Minnesota and in Ohio; and in sixteen other states more or less fruitful efforts have been made. What has been done is only a beginning. Each state should have its state sanatorium and each city of considerable size should provide its own municipal institution. There is need also of industrial colonies where persons in whom the disease has been arrested could be employed in light outdoor work, such as horticulture and the keeping of poultry, pigs, and bees, under conditions which would prevent relapse and would enable them to be at least partly self-supporting. There should be well-equipped free dispensaries in every city. There should be in every city a s^^stem of control by the department of health and a private organization to instigate and supplement public efforts. All these are pressing needs. But there are several other respects in which the United States is peculiarly negligent. One of these is the care of consumptives in public institutions. With an adequate sanatorium and hospital system there will be no reason why consumptives should be found in almshouses. Pending this solution of the question, however, they should be housed in a separate wing, if there is only one building available, or separate wards, or in tents. The extension of sanatorium provision will not solve the problem of the consumptive in hospitals for the insane and in correctional institutions. It is of the utmost importance to the welfare of the public that this question should receive intelligent consideration. There is the less excuse for neglect in this line of work for the control of tuberculosis because experience has already demonstrated that favorable results can be obtained from comparatively slight expenditures. Another glaring deficiency in the American armament is in provision for advanced cases. Houses of rest are urgently required, where patients who are not suitable candidates for entrance to sanatoriums for early cases and who cannot be cared for properly in their homes can be received and made comfortable in their last months. Ultimately, with the development of facilities for preventing tuberculosis and for curing it in its inception, the need for this class of institutions will be practically eliminated ; but for some time to come they will be essential. gent is in its provision for children suffering from non-pulmonary tuberculosis. England has a large hospital for such cases at Margate and in France there are seaside hospitals for them with an aggregate capacity of four thousand beds. The only attempt to provide seaside treatment in America is the experimental camp of the New York Association for Improving the Condition of the Poor. At the Convalescent Home of the Children's Hospital of Boston the open-air treatment in the country has been inaugurated ; and at Loomis and Stony Wold Sanatoriums and Seton Hospital, in New York State, special provision is made for children. But these are the only efforts of the kind that have been discovered. There are many signs that interest in this work of controlling and eradicating tuberculosis is only in the incipient stage, if a technical phrase may be used, and the indications are that it is rapidly developing. There is every reason to hope that the second edition of the Directory will be twice the size of this volume. It may not be out of place to express another hope, for which there is also a basis, that in the second edition it will not be necessary to vary the spelling of the word "sanatorium." It is intended to publish revised editions at whatever intervals may be demanded by the progress made. With this in view all readers are asked to send corrections of the material included in this issue, information in regard to new organizations of any sort, and suggestions for increasing the value of the Directory as a book of reference. L. B, INCIPIENT TUBERCULOSIS Sanatoriums may be broadly divided into two classes : those which aim at the restoration of patients, and those which are merely designed on humanitarian principles to care for hopeless cases, and to prevent them from infecting others. Formerly a consumptives' hospital was regarded simply as an asylum for hopeless cases, and such institutions, for far advanced cases, are as much needed as ever on humanitarian grounds, and to prevent such cases from infecting those about them. The modern sanatorium, however, represents an attempt to cure, and keeps this end in view in limiting admission to favorable and early cases. It recognizes that what success is to be obtained in treating its patients is dependent on an early diagnosis, and on a thorough application of its methods of treatment before the general health has become much impaired and the organic damage extensive. The first requisite, therefore, for admission to these institutions is that the case should be a truly incipient one, or at least that there should be a fair prospect of arresting the disease. The earlier the tuberculosis is detected and the patient informed of the true nature of his malady, the better will be the chance of cure, for if he be deceived as to the serious meaning of his slight symptoms he is not likely to make willingly the necessary sacrifice of time and money, and would lose the opportunity for restoration. About seventy-five per cent of applicants are refused at the sanatoriums for the treatment of incipient tuberculosis because their cases are considered too far advanced, though some institutions take a fair proportion of advanced cases. The modern sanatorium represents the most favorable environment attainable for the consumptive, and depends for its efficiency on the following factors : a good climate, buildings specially adapted for this method of treatment and for protecting its inmates from infection, facilities for living an outdoor life in all kinds of weather, good food, and strict medical discipline concerned. Climate of late years has not been considered so essential as formerly. It has been shown undoubtedly that excellent results are obtained by the open-air method in sanatoriums situated in climates laying no special claim to any favorable influence on tuberculosis, but it cannot be denied that a good climate must be a factor of considerable value in securing the most favorable environment attainable for the consumptive, and that climate should always be utilized when available. The situation of the institution, so far as exposure, drainage, water supply, shelter from prevailing winds, and freedom from dust-laden air, are concerned, is universally recognized to be of the utmost importance, as well as the construction of the buildings. Either the tent, the cottage, or the pavilion plan is generally adopted by the most successful institutions, as tending to segregate patients and to afford them the best conditions of sunlight, ventilation, and convenience in living the outdoor life which is considered essential to cure. Special care of the expectoration, scrupulous cleanliness, sunlight, abundant air space and ventilation, are relied upon and have been proved thoroughly efficacious to protect patients from any evil effects of aggregation. There is much less chance for a susceptible individual to become infected in a well-planned and well-directed sanatorium than anywhere in the ordinary walks of life. Facilities that enable the patient to sit out of doors in any kind of weather, and to sleep out of doors on sheltered verandas at night when ordered by the physician, are among the important features of the modern sanatorium. An infirmary should also always be available, where the acute relapses and complications of the disease can be treated by keeping the patient in bed, often for weeks at a time, with good nursing, and yet not interfere with his open-air treatment. Ever\fthing is planned to encourage living out of doors with comfort in any kind of weather, and to render this in no way irksome. This habituation to an out-of-door life, and to the natural changes of temperature, and inclemencies of weather, is a potent factor in invigorating the patient and in increasing his resistance to a disease which is so largely due to an indoor life and its evil consequences. Cold, tepid, or hot baths are an important element of the treatment, and should be easily available to every patient. The quantity and quality of the food, the intervals of rest and exercise, the occupations and amusements of the patients, are all under the control of the physician, and discipline is the keynote of success. The patient lives constantly under the direction of the physician. The duration of the patient's treatment should be from five to six months or more, as little that is permanent in the way of cure can be accomplished in most cases by a shorter stay. The education the patient receives in these institutions is of the utmost value to him in teaching him, as he can learn nowhere else so effectually, how to protect himself and others from infection, and how to live and care for himself if relapses occur after he has left the institution. ADVANCED CASES The success of the crusade against tuberculosis which now is being preached and inaugurated all over the civilized world will in a great measure depend upon the manner in which the resources at hand are put to practical use. Tuberculosis is so prevalent, so widespread, and so paralyzing in its influence that a movement for its extermination necessarily becomes a herculean undertaking. So many things that could be done suggest themselves to one that one hardly knows what ought to be done first. With limited resources it is therefore of some importance to inaugurate first those measures which promise the best returns with the least outlay of money. Of the measures which may be classed as of importance the establishment of hospitals for advanced cases easily stands first. This does not appear to be so at first blush, but proves to be so upon analysis of the various measures in all their influences. Tuberculosis is a contagious disease which depends upon intimate contact for dissemination and which probably never is communicated except by intimate contact. This contact, moreover, must take place in an enclosure and vmder proper conditions. Among human beings the lower down in the scale of prosperity the better are the conditions for implantation, because not only are the dwellings in which the poor live the most ideal enclosures for the propagation of the disease, but the poor themselves constitute the most ideal soil for its implantation and growth. We know from clinical observations, moreover, that the last few months of life of a consumptive constitute the time when seed for new implantations is most generously given ofif. This is the time, too, when the person afflicted, on account of his symptoms, is apt to house himself closely and thereby create the contagious environment which is most potent for new implantations. Here, again, the lower in the scale of prosperity the greater the likelihood that the house occupied by the consumptive will be made a contagious environment capable of giving implantations. once has been implanted in a person it is a long and difficult process to get it out of him. Even when physical health has been restored to such a person he may contain tubercle bacilli in his tissues and at times give them off as a seed supply for new implantations. A person who never has had an implantation of tuberculosis is therefore in every way better off and is a more valuable citizen, other things being equal, than a person who has had tuberculosis, however well the latter may become. This, of course, is entirely from the viewpoint of preventive medicine. If the tuberculous matter given off by all tuberculous subjects in the world could be sterilized immediately when given off no new cases of tuberculosis could arise, and when all the present tuberculous subjects would have died human tuberculosis would be extinct. Whilst to accomplish this is theoretically possible, practically it is impossible. A very considerable proportion of the human race at the present time is tuberculous. Many of these people need only to be told what to do to make themselves harmless to others. Many more have the disposition to do what is necessary, but lack the intelligence, the knowledge, or the means. Some have the intelligence and the means, but not the disposition. Others, perhaps a fcAV only, lack the intelligence, the means, and the disposition. The health of a community is no more secure than is the sanitary guard around the humblest home. It is the poor and the lowly who serve the rich and. the proud, and it is therefore through the poor and the lowly that disease is most easily spread. A poor man not only comes in contact with those of his own class, but he is intimately associated with people of every class. He necessarily carries with him the disease-breeding environment of his own home wherever he goes. If he has tuberculosis in his home and preventive measures are not practiced in that home, his clothing is saturated with tuberculous matter in dried pulverized form and he is a source of danger to every one with whom he comes in contact intimately for a long enough period of time. The danger to the community from a contagious case of tuberculosis in a poor family grows in geometrical progression. Under the stress of poverty and deprivation and hardship such a case will give rise to new implantations in every member of that household during the time that the patient is confined to the house, and in a little while there will be a number of walking distributors of contagion instead of one. Each of these new cases in its turn becomes a propagator of a number of cases, and in this way the disease is spread on. The dying consumptive undoubtedly is the most prolific source of the spread of contagion. The beginning of a comprehensive scheme for the prevention of tuberculosis should therefore be with him. To make him absolutely innocuous in his own home is difficult and expensive. It means the provision of a skillful attendant to watch over him, ample bed linen for change when the bed linen has been soiled, and such preventive measure supplies as spit-boxes and napkins. The difficulty of keeping him sterile can only be appreciated by those who have tried it. The expense is high, even in a hospital where a number of patients are under the supervision of a single attendant. Without an attendant it cannot be accomplished. The patient grows so weak toward the last that he can no longer avoid soiling his bed linen with sputum and just in proportion as he grows weak the amount of broken down tissue which he ejects increases in quantity. One of the first things to do then in every community in the crusade against tuberculosis is to establish wards or hospitals for poor dying consumptives. In the larger cities one or more special hospitals should be built and equipped. In smaller cities and towns where the size of the population would not warrant such an expense a ward in some general hospital may be set aside for this purpose Whether a ward be set aside or a hospital built, the equipment should be for the treatment of the patient along modern scientific lines, and not for the mere maintenance of dying people. Even the dying consumptive should be given every opportunity for recovery, and when recovery is no longer possible should nevertheless be made to feel that he is treated with hope and not left an outcast of human sympathy. sumptives. The contagion of tuberculosis is only in the expectoration or broken-down tissue, and this can easily be sterilized as it comes from the patient if he is under proper supervision and has good care. HOSPITALS FOR ADVANCED CASES Military discipline is necessary and the nurses and attendants must be especially trained for the work. Until the patient becomes helpless in bed he usually can be taught to keep himself sterile and generally he does so when he is helped and watched over. It is only when he becomes helpless that there is any difficulty. At this time it must be accomplished by the attendants altogether independently of him. The bed linen must be changed every time it is soiled, even though it be a half dozen times a day. In doing so it must not be agitated, and it should immediately be put into a laundry bag and removed before the broken-down tissue has thoroughly dried. Cleanliness is the watchword. Rooms in which dying consumptives live must be scrubbed daily, and everything in them must be kept absolutely clean. With such care there can be no contagion, either to people in the rooms or to people elsewhere in the same building. In cities and towns where a hospital cannot be built for dying consumptives, and where wards for their maintenance cannot be obtained, an ordinary house can be turned into a hospital for consumptives and can be equipped for the best scientific care of such patients if only a little common sense is used. After all it is more the intelligence and devotion of attendants than it is the character of the building which counts in the prevention of the disease. It is true the maintenance of a consumptive in a building which has been adapted for his treatment is less expensive than it is in a building which is improvised for such a purpose, but the difference in cost is not prohibitive. The influence which the care of dying consumptives in hospitals exercises for prevention is well illustrated in the reduction of the death rate from consumption in London during the last fifty years. A little over fifty years ago the English people began to establish hospitals for consumptives in London as a matter of humanity. The work met with favor and the beds gradually increased until they numbered thousands. At that time the death rate from consumption in London was about the same as that in Paris and all the large cities in the world, namely about four per thousand. No other preventive measure was introduced in London. At the end of fifty years, London, the largest city in the world, had the lowest death rate from consumption of all, about two per thousand, and Paris, where no consumption hospitals had been established, still had its four deaths per thousand from the disease. The reduction in London undoubtedly had been due in large part to the segregation of the consumptive poor in hospitals. Lawrence F. Flick. able to move about. Capacity: In Palm Lodge, 30; in the colony, 25. Terms : $25 to $35 per week ; in the tent colony, $9. Resident Physician and Superintendent: Henry M. Stone, Palm Lodge is two miles out of Phoenix, within one block of the trolley. The altitude is -about 1,150 feet. There is a main building of stuccoed brick, containing fifteen rooms, and eight two and four room cottages, each supplied with its own bathroom. A tent colony is now being constructed, two miles distant from Palm Lodge, which will also be under Dr. Stone's management. There will be accommodations for twenty-five and the rate of nine dollars per week will include medical attendance. It is expected that this colony will be completed by December i, 1904. Not exclusively for the treatment of tuberculosis, but cases of consumption are received at any stage of the disease, and cared for in separate wards and rooms. There is accommodation for 20 consumptives. Terms : $14 per week; there is no provision for free treatment, but exceptions are occasionally made in cases of extreme poverty. visiting and consulting staff. The hospital is in charge of the Sisters of Mercy and is supported by fees from patients. It is housed in a large brick building, surrounded by attractive grounds, five blocks out of the city proper. There is no resident physician. The location is two miles from the city, at an altitude of 2,400 feet. The tuberculosis sanatorium is a brick building built around an open court, with a porch on both sides. There are no wards. Each patient's room is 17 by 14 feet, and has two windows and a double door. The institution is under the charge of a Roman Catholic sisterhood, the Sisters of St. Joseph. Resident Physician : F. C. Melton, M. D. The Altadena Health Resort Company has established this sanatorium on a tract of 160 acres, half a mile east of Altadena, which may be reached from Pasadena by electric car in twenty miinutes. On the north the place is protected by a semicircle of mountains, while it is open to the south and west, commanding a wide view of the San Gabriel Valley. The altitude is 1,800 feet. A central building contains offices, dining-room and parlors. Most of the patients live in tent cottages. The lighting is by electricity and all the buildings are connected by telephone. This novel adventure is supported by Mr. N. O. Nelson, a Saint Louis manufacturer, who bought for the purpose 200 acres just at the entrance of the Great Desert. Indio is on the Southern Pacific Railway, half-way between Los Angeles and Yuma. The land is 20 feet below sea level, in the Coachella Valley, protected from wind and fog on both sides by mountains. The average rain fall for the year does not exceed one inch, and all winter days are comfortably warm. The ranch is being irrigated and beautified and buildings are being erected for the use of the colonists. Their individual homes are floored tents of various sizes. Seventy-five acres are now under cultivation, and it is hoped that the produce will supply the camp. The work on the place is done chiefly by the able-bodied colonists. Hospitality is extended to whole families, not merely to the invalid member, and provision is made for a permanent home for convalescents. For consumptives who have been residents of Los Angeles County for at least one year and who are without the means to go elsewhere ; persons in all stages of the disease have been admitted, but it is desired to receive in the future none who are bed-ridden. sicians are within easy reach. The plant at present consists of 25 acres of rolling land, on the Chavez Ravine Road, adjoining the large city park and surrounded by it on three sides, an administration building with detached kitchen and laundry, a one-and-a-half-story dormitory for patients, and one tent cottage. It is located within the city limits, but away from car lines and buildings. The altitude is about 400 feet. Voluntary contributions are practically the only source of support. Thus far no debt has been incurred and an endowment fund of $6,000 has been secured. The average cost per week per patient during the first year was $12.35. Seventyfive applications were received and thirty-four patients cared for during the year. These patients came originally from eleven states of the union and eight European countries. Mentone is one mile from Redlands, in a valley protected on three sides by mountains, while to the west stretch miles of orange and lemon groves. The altitude is 1,700 feet. This sanatorium is, strictly speaking, a hotel where well-to-do patients can have sanatorium treatment and where their relatives and friends are also received. Tents are provided on the grounds for patients who prefer to sleep out of doors. For the treatment of cases of pulmonary and laryngeal tuberculosis which offer a fair chance of permanent and material improvement ; no patients are received in whom the disease is so far advanced that their condition will discourage those who are in the early stages. This sanatorium is sixteen miles east of Los Angeles, in the foot hills of the Sierra Madre Mountains, at an elevation 'of 1,000 feet above the sea. Monrovia is on the main line of the Monrovia and Duarte branch of the Southern Pacific Railway, and the Monrovia branch of the Pacific Electric Railway. The site is a natural park of over eight acres, occupying an eminence 400 feet above the town, above the fogs and protected from storms. From its commanding location there is an uninterrupted view of the San Gabriel valley, with its worldfamed orange groves, and the Sierra Madre Mountains. There are at present a central administration building, one cottage, a sun parlor and open-air pavilion, and a number of tent houses. The plans for further buildings contemplate three pavilions, connected by corridors and balconies, and containing sixty rooms facing south. One of these pavilions will be ready for occupancy in January, 1905. All the buildings and furnishings are in accordance with the latest dictates of sanitary science. Thereis a well-equipped clinical laboratory, and a laboratory for experimental and research work will soon be constructed. Capacity : 17, Terms : those v^ho are able to pay something are expected to do so, up to a maximum of five dollars per week; for the destitute care is entirely free. The Settlement is located on forty acres of rolling land, not under irrigation, six miles from the city, at an elevation of 1,500 feet. All patients live in tents, which are supplied with the ordinary necessities, but of a verv primitive kind. A wooden building contains the dining room, kitchen, store room, and bath. This sanatorium camp was established, and is maintained, exclusively for consumptives who find themselves stranded in Redlands without funds, or with insuinficient money to provide themselves with proper care. It is supported chiefly by contributions ; there are countv and city appropriations aggregating $75 per month ; and a small, irregular amount is derived from patients' fees. The demands of the locality absolutely prohibit the reception of patients from any other place. Residents of the town who desire to be admitted should apply to the ]\Iatron or to one of the INIedical Directors. ly by the addition of tents. Terms :$25 per month, including all expenses except laundry ; there will probably be arrangements for admitting needy patients free of charge. Resident Physician : Dr. Greenard. This sanatorium has been established by the Salvation Army in memory of Mrs. Booth Tucker. It is located on an isolated part of the Salvation Army Farm Colony in southeastern Colorado. It is in the midst of the great plains and has an altitude of 3,500 feet. The Administration Building is a large threestory structure of rock. It will contain, in addition to the dining room, library, and other public rooms, some sleeping accommodations. Most of the patients, however, will be housed in substantially built tent cottages. a special nurse in case one is needed. Resident Physician : John E. White, M. D. Nordrach Ranch is fortunate in its location. At an altitude of 6,000 feet, quite removed from the dust and smoke of the city, it is protected on the north by Austin Bluffs, and lias in front an uninterrupted view of Colorado- Springs, three miles distant, and the range of mountains. The central building is of red stone and contains twenty-four rooms, six of which are reserved for patients who may temporarily need hospital care. The ordinary sleeping apartments for the patients are octagonal tents, communicating directly with the nurses' tent by electric bells. Practically all the time is spent in the open air. The resident physician sees each guest at least twice a day and the physicians in Colorado Springs are always available for consultation. Exclusively for early cases of pulmonary tuberculosis ; when accommodations are limited, preference will be given to candidates from western Pennsylvania. en, M. D. This Sanatorium has been erected by Mr, Lawrence C. Phipps, of Pittsburg, as a memorial to his mother. There are five buildings — a three-story administration building, an infirmary, two pavilions and a power house — all in the old Spanish Mission style of architecture. In the administration building are the reception room, board room, offices, dining rooms and kitchen, besides a library of 1,500 bound volumes for the use of the patients. In this building also are the quarters of the administrative staff and attendants. The medical building contains on the first floor, besides a very complete laboratory and treatment rooms, reception and consultation rooms. The second floor is devoted entirely to an infirmary, which is provided with a well-equipped operating room. There are two pavilions, one for men and the other for women, opening upon wide porches, divided by canvas partitions for sleeping purposes. The power house furnishes electricity, ice and refrigeration, together with power for an electric laundry. This laundry is equipped with the most modern appliances, including a complete sterilizer. Sputum, garbage and sweepings are disposed of in a special device for cremation. The grounds include 160 acres of dry, sandy soil on the plains east of Denver, at the highest elevation near the city, about 5,400 feet. The distance from the heart of the city — over seven miles — and the extent of the estate, ensure against smoke and dust. The Sanatorium is at Sixth and Hyde Park Avenues, reached from Denver in thirty minutes by electric cars. Especially for early cases of pulmonary tuberculosis, but occasionally others in need of out-door life are received. For young men of limited means who have a good prospect of recovery ; preference is given to members of the Young Men's Christian Association. Capacity : 45, one man in each tent. Terms : $25 per month ; light work in partial payment of this charge is provided for many, but cannot be guaranteed until the physical condition of the applicant is fully understood; the patient's knowledge of farm work is also taken into account. This Kealth Farm originated in the experience of the Colorado Young Men's Christian Association in dealing with the problem of finding suitable places for the young men who go to Colorado from all parts of the country in search of health. Funds for the execution of the plan to its present stage have been provided by friends in various parts of the country, the principal gifts having been made by Mr. and Mrs. David Brothers and Dr. E. P. George. Many of the Young Men's Christian Associations throughout the country have given tents completely furnished and others are planning to do the same. The value of the present equipment is $45,000. The Farm consists of two tracts of land. The tract which is now being improved contains thirty-four acres of fruit land five and one-half miles northwest of the city, on the Denver, Lakewood and Golden Railroad. There is a station at the corner of the farm. The sixty acres of unimproved land will be developed whenever the funds allow. The site of the present farm is 5,400 feet above sea level and has a diversity of natural features. The improvements include an administration building, stables, forty-five cottage tents, a water-tower observatory, and a tent hospital. From the first the number of applicants has far outnumbered the places for them. Foxhall is located opposite the public library, three blocks from the Capitol. It is a single large house, the home of Dr. Beggs, who is one of the physicians to the National Jewish Hospital for Consumptives and editor of the Colorado Medical Journal. No patient is allowed to remain who refuses absolute obedience to directions. The: Home: "The only rec[uirements for admission are that a person is worthy of a Christian home and presents a good chance of being benefited by the climate, and presents a letter from some clergyman or from some one the superintendent knows." Terms : $25 per week for those who require a nurse ; there is one building, accommodating 40 persons, in which the charges are $25 per month. The Home comprises four buildings : St. Andrew's House for men, Grace House for mother and son or husband and wife. Emily House for women, and Heartsease for the very sick. These cover an entire block of land, and are connected by glass covered porches. The Home is ten minutes' ride by three car lines to the Denver post office, and is so situated that it commands a view of the entire city, the plains for hundreds of miles, and the Rockies for one hundred and fifty miles. It is under the direct ownership and management of the Episcopal Church of the Diocese of Colorado. Superintendent: Moses ColHns, M. D. While this institution is within the Hmits of Denver, it is nevertheless sufficiently removed from the congested part of the city to have an abundance of the sunshine and the pure, invigorating air for which Colorado is noted. The altitude is about 5,200 feet. The buildings are on the pavilion plan, containing rooms of from one to four beds and twelve-bed wards. Application for admission must be made from the city where the applicant resides, on prescribed forms. The applicant must be examined by the physician appointed by the hospital authorities at the place where he resides, and the application must be sent on blanks provided for that purpose. No other form of medical examination will be accepted, nor any made by other than the regularly appointed physician. The patient's character must be investigated and endorsed by the local trustee. Each application must be accompanied by a guaranty, approved also by the local trustee or director, that the patient shall not become a charge upon the community after he leaves the hospital, and that in case his return may be advisable at any time his transportation will be furnished. No applicant should be sent to Denver, or allowed to go, until he has received official notice of his admission. This society was formed a few months ago by Jewish residents of Denver, most of whom were cured consumptives, with the object of helping- their co-reHgionists who have gone to Colorado in the hope of regaining their health, but have come to want before they have recovered. A tract of twenty acres of land has been purchased in the suburbs of Denver, three-quarters of a mile out of the city, a dining-room and a kitchen have been erected, and twelve tents have been installed and furnished. It is hoped to increase the capacity to one hundred by the end of the first year. It is planned to establish a dairy, a poultry yard, and vegetable, fruit and flower gardens, the produce from which will, it is expected, supply the camp. Patients who are able will do light work connected with these enterprises, but under the direct supervision of a physician. There is a permanent resident physician ; Dr. I. Singleton Garthwaite, of Denver, visits frequently, and to him all applicants must present themselves before admission will be granted. Sunrise Mountain Park, the site of Resthaven, has an altitude of 5,800 feet, and all the advantages in the way of scenery that the Rockies and the great plains can provide. Morrison, the nearest station, on the Colorado and Southern Railroad, is five miles distant. The buildings are one-room cottages and tents scattered among the pines and bearing- the names of the states which have donated them. An endowment from Lillian Garthwaite-^^■ylie and various other gifts supplement the fees received from patients. State vSaxatorium : Agitation for a state sanatorium was begun by the state Board of Health and others three years ago. Twenty-five thousand doUars was granted by the legislature to a private institution, the Gaylord Farm Sanatorium (See page 41 j, but no state institution has yet been established. This institution is situated one mile from the village, on a ridge of the Berkshire foothills, at an altitude of about 800 feet. The grounds cover about eighteen acres, part of which is woodland. The individual sleeping apartments are 10 by 16 feet and 10 feet high. There are no wards. Patients are under the strictest hygienic routine, constant medical supervision and constant efficient nursing. The average course of treatment covers twelve weeks ; no patients are retained longer, and a total arrest of the disease is expected within this period. Application for admission should be made to either of the following: Dr. ^I. J. Brooks, New Canaan, Conn.; Dr. Hubert Arrowsmith, 170 Clinton Street, Brooklyn, X. Y. This sanatorium is due to the efforts of the Xew Haven County Anti-Tuberculosis League, and is under its management. Situated on a plateau two miles from the town and above it, and fourteen miles inland from New Haven, the Sanatorium overlooks the towns of Wallingford and Meriden and the valley in which they lie. The altitude is 390 feet. There is an administration building, containing offices, rooms for the doctor and matron, recreation hall and accommodations for fourteen patients. Four cottages provide for four patients each, in rooms opening on porches. The kitchen, dining room, and laundry are in separate buildings. There is electric lighting and steam heat throughout and the water supply is from artesian wells. In connection with the Sanatorium is a farm of 250 acres. Applications should be addressed either to Dr. David R. Lyman, Wallingford, or to one of the consulting physicians, as follows : Dr. C. \\'. Gaylord, Branford ; Dr. S. D. Otis, ]\Ieriden ; Dr. J. P. C. Foster, Xew Haven ; Dr. O. T. Ostborne, Xew Haven : Dr. Henry L. Swain, X^ew Haven ; Dr. F. \\'. AA'right,. X^ew Haven ; Dr. Carl E. ]\Iuno-er. AVaterburv. Visiting Physician : D. Percy Hickling, M. D. Consulting Board : Drs. G. Lloyd Magruder, W. P. Carr, W. S. Bowen, J. Tabor Johnson, H. L. E. Johnson, H. S. Dye, Swan M. Burnett, F. T. Chamberlain, George M. Kober. The first ten was erected in April, 1904. Three others have been added since, until there is provision for both white and colored men and women. Three of the tents are entirely of wood, open on the south side, and with an elevated roof for A'entilation. Naval Hospital : A tuberculosis camp, consisting of tents accommodating fifty patients, has been established in the grounds of this hospital, as a temporary device for meeting the exigent needs of the Department of the Navy. The Bureau of Medicine and Surgery of the Department is making a study of the various abandoned army posts which have favorable locations, with a view to the establishment of a sanatorium for the treatment of cases of tuberculosis arising in the United States Navy and United States Marine Corps. The authority of Congress will be necessary before title to any selected post can be acquired by the Department and work begun. Medical Superintendent: A. H. Sinclair, M. D. The situation is two miles from the sea, at an elevation of 300 feet. The building for consumptives contains a free ward and separate rooms for pay patients. Support is derived partly from endowments and partly from a territorial appropriation. A committee of the State Medical Society has been appointed with the express object of securing the establishment of a state sanatorium. (See pages 45, 236.) Medical Director: A. F. Kramps, M. D. This, the first institution in Chicago devoted exclusively to the treatment of pulmonary tuberculosis, is located northeast of the suburb of Austin. Funds for the building were supplied by gifts secured mainly through the efforts of the Roman Catholic sisterhood in charge of the sanatorium. Current expenses are met by fees from patients and contributions. For poor consumptives of Cook County; patients admitted are presumably dependent, but in consideration of the slight provision for this disease in Chicago noclose inquiry is made on this point; all stages are treated. This hospital is seven miles west of Lake [Michigan, on the highest point in the county, 800 feet above sea level. Other natural features are the same as are found in Chicago. The original building is of brick, three stories high ; the new hospital consists of four frame one-story wards, connected by a large solarium-hall, and a two-story administration building. This little experimental colony, under the auspices of the Illinois State ^Medical Society, is located on a bluff, 120 feet above the Illinois River. The tents are arranged around a quadrangle in the center of the ten-acre tract which constitutes the grounds. The kitchen, dining-room, and parlor, as well as the sleeping rooms, are separate tents, of waterproof cloth, with wood floors, and lighted by electricity. Patients are received from any part of the state. Efforts to secure the establishment of a state sanatorium have been made by the State Medical Society during the last four years. In 1903 a resolution appointing a commission to investigate the subject was defeated in the legislature. A state association (see page 237) has recently been formed with the primary object of securing a state institution. FORT WAYNE. St. Rochus Hospital is a small building where ten consumptives can be cared for by the Sisters of "The Poor Hand Maids of Jesus Christ." It is hoped by the Sisters that in the course of lime they will be able to erect a hospital worthy of the name. For incurable cases of consumption who are recommended by the Flower Mission Society and approved by the Superintendent of the Hospital. Capacity : 26. Superintendent: Paul Frederic Martin, M. D. The new pavilion occupies the northern part of the City Hospital grounds, which have an altitude of 822 feet. It is a one-story brick building, surrounded by a veranda, containing two wards for ten beds each and six private rooms. At the last session of the legislature the Board of Control of State Institutions was requested to make an investigation in regard to the treatment of tuberculosis in sanatoriums, as a preliminary step to considering the establishment of a state institution. One thousand dollars was appropriated for the expenses of the inquiry. The building is of unshaped field boulders, two stories high, in a wooded tract of 15 acres, 1,200 feet above sea level. The surrounding country is wild woodland, sloping down to the Des Moines River on the west. A committee of the State Medical Society is framing a bill to present to the legislature. The State Board of Health and others interested will co-operate in supporting the measure. Nearest stations : West Minot, on Portland and Rumford Falls Railroad ; Paris, on Grand Trunk. Exclusively for incipient cases of pulmonary tuberculosis. Capacity: ultimately 100; at present there is room for 30. Terms : 6 free beds ; $10 per week for the others. Medical Director: Estes Nichols, M. D. The State Association for the Treatment of Tuberculosis, to v/hose efforts this sanatorium is due, has secured 330 acres on a southern slope in the foothills of the White Mountains, at an altitude of 1,200 feet, near the Poland Spring- region. A public highway runs through the center of the tract. Over a third of tlie estate is fertile arable land, which will make it possible to produce the required supplies of milk, fruit and vegetables. One hundred and thirty-five acres are woodland. The buildings are on the cottage system with individual sleeping rooms,, hog camps, open on one side, are to be constructed for winter sitting-rooms. The sleeping pavilions have across the entire front double glass doors which are closed only while patients are rising and retiring. Patients do not, however, dress in these pavilions, but go directly from them into heated dressing-rooms. It is hoped that the endowment will soon allow an increase in the number of free patients who can be received. The State Tuberculosis Commission (see page 237) is authorized to consider the question of state sanatoriums and report to the General Assembly in January, 1906. No pay patients are received. Chief Resident Physician : William H. Smith, M. D. There is a small two-story building for women on the grounds of the City Almshouse and Hospital. The new building for men, now in process of erection, will be 150 feet long and two stories high. The hospital buildings are 160 feet above tide water. Exclusively for white patients, preferably in the early stages of the disease, though under pressing circun> stances far advanced cases are received. from which it is reached by electric cars in thirty minutes. The hospital is known as the Eudowood Sanatorium. It is at an altitude of 500 feet among forest-covered hills. There is a large main building, containing five private rooms and tv^ro wards, one for men and the other for women, one memorial cottage of four rooms and another of six rooms, all with porches looking to the south and west ; two or three shacks and two or three army tents. The memorial cottages were built by the daughters of Mr. Theodore Hopper in memory of their brother and by Mrs. Nelson Perin in memory of her husband. A fund is being accumulated for the extension of the hospital in some favorable situation in the Blue Ridge ]\Iountains, where only hopeful cases are to be received. are inconsiderable. The officers are : Dr. Henry Barton Jacobs, President ; Rev. Arthur Chilton Powell and Robert Garrett, Esq., Vice-Presidents ; Rev. A. Guttmacher, Secretary ; David H. Carroll, Esq., Treasurer. sachusetts Central Railroad, a mile and a half distant. For earlv cases of pulmonary tuberculosis ; patients must be residents of the state and not too far advanced to admit of reasonable hope of radical improvement. Terms : $4 per week ; there are no free beds, but the trustees are empowered to allow a few cases to remain at public expense ; in many cases the bills are paid by cities or charitable organizations. To Massachusetts belongs the honor of having established the first state sanatorium in the country. It is located near the center of the state, about 50 miles from Boston and 11 miles from Worcester, at an elevation of 1,000 feet. The buildings are on a southern slope, protected on the northwest by a wooded hill. The pavilions for patients are one or two stories high, extending to the south, each terminating in a solarium and piazza, and all connected on the north by a covered corridor. Dr. Mncent Y. Bowditch and Dr. Herbert C. Clapp, of Boston, have supervising charge of the medical treatment. Besides Dr. Alarcley there are three assistant resident physicians. A point of interest to all who are engaged in planning similar institutions is the opinion of the superintendent, after five years' experience at Rutland, that open wards, containing from fifteen to twenty-five beds, are preferable to individual sleeping-rooms. Of the incipient cases discharged in the last four years, 73 per cent have been arrested or apparently cured. The uniform charge of $4 per week covers less than half the actual expense for each patient. An annual appropriation is m.ade by the legislature ; the amount in 1903 was $90,000. Patients desiring admission to the sanatorium in Dr. Bowditch's service may apply at the Boston office of the sanatorium on Wednesdays, or at the sanatorium in Rutland on Fridays. Patients desiring to enter in Dr. Clapp's service may apply at the Boston office of the sanatorium on Saturdays, or at the sanatorium in Rutland on Mondays. MASSACHUSETTS The Boston office is at the new Out-Patient Department of the Massachusetts General Hospital on North Grove Street, where examination of applicants is made on Wednesdays and Saturdays from 1.30 to 3 o'clock p. m. Fall River, by Dr. A. S. MacKnight, 355 North Main Street, Wednesdays and Saturdays, 2 to 3 p. m. Lowell, by Dr. Boyden H. Pillsbury, 58 Kirk Street, Wednesdays and Saturdays, 2 to 3 p. m. Consumptives are isolated from the other patients, the men in a separate building accommodating about 60, the women in a ward of the general hospital. Both places are inadequate to the demand. Long Island, on which the institution is situated, is five miles from Boston and the hospital buildings are 75 feet above low water. Channing Home is a light and well-ventilated brick building, four stories high, located in the city in a quiet street. It is supported entirely by endowments. All patients are cared for free of charge. Medical Board : Herbert C. Clapp, M. D. ; J. Tucker Cutter, M. D.; Samuel H. Calderwood, M. D. ; E. P. Ruggles, M. D. ; Percy G. Browne, M. D. ; and two internes. The Consumptives" Home is the principal one of a group of charities founded in 1864 by the late Dr. Charles Cullis, and built up and supported entirely by voluntary contributions and legacies. The building now occupied was erected seven years ago. It faces Franklin Park, from which it is separated by Blue Hill Avenue and a wide stretch of lawn. The grounds, consisting- of about six acres, are dry and sandy. On the grounds ir. a small home for children whose mothers are in the Consumptives' Home. Superintendent. Free Home f'or Consumptives in the City oe Boston, 428 Ouincy Street, Dorchester (1892) : For poor consumptives in all stages of the disease. Capacity: no. formed one-third of the total number of patients. There is room for about 30 tuberculous patients. Terms: 15 free beds; $7 per week tor others, in wards. There is no resident physician. The grounds of this hospital adjoin those of Harvard and cover seven acres. The building when completed will have a wing at each end, and the whole structure will be four stories high. Terms: $15 to $30 per week; a limited number of patients can be received at greatly reduced rates. Medical Director: C. S. Millet. M. D., Brockton. There is no physician in residence. The main building is an old colonial house. All the bedrooms face south, and sleeping balconies have been added to some of them. Additional accommodations are provided by small sleeping shacks near the house. The site is a well-drained gravelly hill, 120 feet above sea-level. Special attention is paid to hydrotherapy in addition to the usual methods of treating tuberculosis. Dr. Butler's small private sanatorium has the same natural advantages as the state institution in the vicinity. The grounds extend over 85 acres of woodland and pasture. The original iDuilding, which is soon to be supplemented by six-room cottages, is a large two-story house with broad piazzas the entire length of two sides. Special attention is given to matters of diet and ■details of out-door treatment. There are also in Rutland three private houses, modified to suit the need of patients, which are directly under Dr. Butler's •control. These houses have accommodations for 41 patients, in small wards containing from two to six beds. One nurse in each house is employed by Dr. Butler to care for the patients. The rates are $7, $7.50 and $8 per week, for board, attendance and medical care. Terms : $5 per week, exclusive of laundry. Medical Director: Vincent Y. Bowditch, M. D. Resident Physician : Walter A. Griffin, M. D. Sharon is a most attractive town 18 miles from Boston, at a general elevation of 350 feet. The sanatorium stands on high ground, sheltered on the north and northwest by thick woods, the whole estate comprising about 150 acres. There is one large building facing south and well supplied with piazzas, an infirmary for those who need hospital care, and cottages for the matron and physicians. Payments from patients covered less than a third of the actual expenses last year, the rest being met by voluntary contributions. The hospital is situated in a grove of white pines, on sandy soil, at an elevation of 135 feet. The tuberculosis building is two stories in height and contains six wards. WELLESLEY HILLS. Convalescent Home of the Children's Hospital : Shack for tuberculous children (December 26, 1903). For children who have been under treatment for tvibercu- needs. A wooden shack has been erected in connection with the Convalescent Home, as an experiment in the open-air treatment of children suffering from tubercular diseases. This shack is 20 by 40 feet, and is lighted by windows in the roof, on each side, and at both ends. The windows are kept open day and night, and the sides of the building are so constructed that they can be opened two-thirds of their length. On the southwest side the doors are kept open all the time in moderate weather. Fifteen children have slept here every night since the building was erected, and it is used as a playroom in the daytime by these same children and the fifteen who sleep in the house. The shack is heated by two "Champion Railway Heaters," and the children are warmly clothed, both day and night. It is of interest that there has not been one case of sore throat or cold among the children. Their appetites improve and they enjoy the out-door life. No children can be received except those who are sent from the Children's Hospital. Repeated attempts, thus far fruitless, to secure legislation ■establishing a state sanatorium, have been made, and will continue to be made, by the State Board of Health, the State Medical Society, and individual physicians. ELOISE. Tut Wayne County House, at Eloise, which cares for the destitute of the county, erected, in September, 1903, hospital tents for the treatment of its consumptive inmates. There is accommodation in the tents for 30 patients, a larger number than is generally in the institution. There is a resident physician. Dr. E.. H. Earle; Dr. Shurly, of Detroit, at whose suggestion the tent treatment was introduced, and Dr. Marker, of Eloise, are the visiting physicians. county commissioners or by the patients themselves. There will be a resident physician ; at present the State Tuberculosis Commission is in charge, of which the chairman is H. Longstreet Taylor, M. D., 75 Lowry Arcade, Saint Paul. Seven hundred acres, at an altitude of 1,500 feet and about 250 feet above Leech Lake, have been secured for the site, and an appropriation of $25,000 has been made to begin building. The Sanatorium will be owned, and supported in the main, by the state, but patients will be required to meet the actual cost of their maintenance. For early cases of consumption; advanced cases are admitted, but are discharged as unfit for sanatorium, treatment if they do not soon begin to improve. is the visiting physician. The Sanatorium is a separate building in connection with Luther Hospital. It is a brick structure, three stories high, containing private rooms and small wards. Any physician is at liberty to place his patients here and care for them himself. For poor patients the hospital charge is $8 per week; others must pay for professional attendance, in addition to charges for accommodations. The altitude is about 800 feet. admitted free if there is room. :^Iedical Director: Wilham Porter, M. D., 3886 Washington Boulevard ; there is also a resident physician. jMount St. Rose Sanatorium is situated outside the city boundaries, on a high site and with 25 acres of ground. The building is new and has 50 rooms. It is supported by voluntary contributions and fees from patients, and is under the supervision of the Sisters of St. Mary. The Emergency City Hospital is located in the heart of the city. The buildings are of brick, four stories high. New buildmgs are in process of erection. It is supported by the city. The establishment of a state sanatorium was recommended in 1902 by the State Commission appointed to consider the subject (see page 241), but the bill was defeated. Further attempts to secure its passage will be made in 1905. Pembroke Sanatorium is situated on the southern slope of Pembroke Hill, at an altitude of 600 feet, overlooking miles of typical New Hampshire scenery. It is reached by the electric railroad running from Concord to Manchester. A pine forest on the north, east, and west affords protection from the cold winds of winter and considerably modifies the temperature. There is an administration building, finished and equipped according to the latest views of sanitary science, and 17 "camps," each accommodating two patients. These "camps" have hard wood floors and are open in front, provided only with canvas curtains for protection when it is necessary. The experience has been that patients improve more rapidly here in winter than in summer, despite the cold. NEW JERSEY State Sanatorium eor Tuberculous Diseases (Projected) : The site has been secured at Glen Gardner, Hunterdon County, and $200,000 was appropriated for buildings by the legislature in the session of 1902-3, but by the omission of a bill authorizing the disbursement of the appropriation it was not available, and a year's delay resulted. In the session of 1904 the legislature again made an appropriation of $200,000. The plans and specifications have received the approval of the governor, as required by law, and the work can now proceed. The plans at present provide for about one hundred patients. staff. The tuberculosis pavilion contains two wards. Patients are admitted in all stages of advancement. The hospital is endowed and it receives an annual subsidy of $500 from the city. The income from these sources is supplemented by fees from patients and by contributions. Not exclusively for the treatment of tuberculous patients, but the recently built annex is reserved for their accommodation ; all stages of the disease are received. sulting staff of ten. The Sanitarium is located on a high plot of ground, in the outskirts of the city. In the tuberculosis building there are four wards and eight private rooms. The Sisters of Charity of Cincinnati are in charge and the staff of physicians is appointed by the Bernalillo County ^Medical Association. The Sanitarium was erected and is still in charge of the Sisters of Charity of Leavenworth, Kansas. It is a three-story building, of brick and stone, 160 feet in length, and well supplied with broad verandas. There are no wards ; each guest has a private room. dence. The nearest town is Silver City, nine miles away. The altitude is over 6,000 feet. All admissions are under the authority of the War Department and are made through the AdjutantGeneral or the Surgeon-General of the United States Army. Exclusively for the ireatment of tuberculosis; admission is g-overncd by regulations of the Public Health and ]\Iarine Hospital Service; eligible pirsons are received in any stage of the disease. Capacity : 225. There are no charges for accepted applicants. Surgeon in command : P. M. Carrington ; there are also in residence five assistant physicians and three pharmacists. This sanatorium is supported by the federal government for the benefit of seamen employed on the merchant marine vessels of the United States, officers and men of the revenue-cutter service, keepers and crews of light-house establishments, and seamen employed on vessels of some other branches of the public ser^'ice, other than the navy. There are more than twenty buildings of various kinds. ]\Iost of them are of stone and adobe, and they are arranged on four sides of a square "Parade Ground,'"" which has been converted into a lawn. More than thirt}- tents are in use. The reservation contains 38 square miles, nearly all enclosed, and produces a great variety of crops. The altitude is 6,150 feet. Las Cruces, in the lower Rio Grande valley, has an elevation of about 3.800 feet. The sanatorium is a mile and a half out of town, in the midst of alfalfa fields. Its grounds include fifteen acres, well planted in shade trees. The building is a two-story adobe, with kalsomined walls and hard wood floors. The Las Vegas Hot Springs Sanatorium Company has leased for its purposes the Montezuma property, formerly a hotel. It is located in a canon, six miles from Las Vegas, at an altitude of about 6,700 feet, and is sheltered from wind and dust storms by the surrounding mountains. The main building IS a four-story stone structure and there are several cottages on the grounds. These buildings are being remodeled and equipped as a modern sanatorium for patients who can pay at least fifteen dollars per week. The Tent City will be pitched on one hundred acres of mesa land adjoining the Montezuma grounds, donated for the purpose by the town authorities. Part of this tract is open and the rest is covered with pine trees. The object here will be to furnish good food and medical attendance at the lowest possible cost. This institution is under the management of the Sisters of Charity. It receives its support in part from the territory and in part from patients' fees. It is located in the central part of the town. Medical Director, in residence: E. S. Bullock, M. D., formerly pathologist and physical diagnostician at the United States General Hospital for Tuberculosis. Silver City is only nine miles from Fort Bayard, which was chosen by the United States Government authorities as offering the greatest climatic advantages for the treatment of tuberculosis. The altitude is 6,000 feet; the average annual rainfall, 12.3 inches; the average number of cloudy days in the year, 37. It is at the terminus of a branch of the Atchison, Topeka and Santa Fe Railroad. The Sanatorium is located "outside the business center of Silver City, on rising ground, protected by hills from the prevailing north and west winds, and overlooking the little town and a wide range of outlying country. . . . The buildings are old California Mission in style, built around a court. . . . The older building is used as an infirmary for patients requiring special care, and composes one side of the square. The new structure ... is really a succession of cottages, possessing all the advantages and none of the disadvantages of the cottage system. Each room is heated by a fire-place, thus insuring additional ventilation. ... A room devoted to hydropathy has been provided in the main building. . . . The principles which govern the care and treatment of patients are, with few modifications, those laid down by the Brehmer school." The Sisters of ]\Iercy are in charge of the business management of the institution, but all medical matters are imder the control of the medical director and his advisors. Ray Brook, Essex County: Primarily for the poor, but pay patients will be received when there is room for them; one year's residence in this state is a required condition. Incipient cases only are admitted. By a provision of its charter the Hospital is required to give preference to the indigent, admitting others only when vacancies occur. The authorities by whom the patient is sent are required to pay transportation to and from the Hospital and $5 per week for maintenance. Physician in charge : John H. Pryor, M. D. The State Hospital is located in the Adirondacks, four miles southeast of Saranac Lake and six miles west of Lake Placid. There is an administration building, with a pavilion on each side, connected with the central building by wings to be used as sun rooms. The 516 acres of land adjoin the Forest Preserve. The altitude is 1,625 feet. This small private sanatorium is situated about i 000 feet above sea level, on a dry sand hill overlooking Owasco Lake. The main building- is a large three-story frame house in the midst of pine woods. Each room has four or five windows and an open grate. On the western side of the house there is a .screen-enclosed veranda for sleeping purposes. In addition to the main building there is a cottage on the summit of the hill. The main building of the Country Sanitarium, situated on a farm of 160 acres at an altitude of 450 feet, is formed of four wings, connected by glass-covered corridors. The distinctive feature of the treatment here is the out-door employment given to selected cases of incipient and convalescent pulmonary tuberculosis. "During the spring, summer, and autumn," to quote from the report of Dr. Alfred Meyer, the consulting physician, "this work has been largely in farm, garden and orchard. The produce and supplies raised were far beyond the needs of the institution, and the prize pumpkins, cabbages, radishes, and ears of corn would have done credit to a country fair. The value of such a regime to the patients themselves is simply inestimable. The out-door life it encourages, the training in a useful and healthful occupation, the stimulus that comes with something accomplished, the reduction of the hours of loafing and brooding, all tend to the betterment of the patient,, both physical and moral." Last year the average time spent in work by the patients for whom it was recommended was two and a half hours a day and the average number of patients at work was twenty-five. A school has been organized for the children and young people. No physician is in residence. This institution is a large building pleasantly located in the city. From the beginning of its work, over twenty years ago, patients in an apparently hopeless condition have not been refused. Frequently, however, a cure has been effected in spite of all the probabilities against it. The income is derived from mterest on endowments, voluntary contributions and a city appropriation. Street, Brooklyn. Kings County Hospital, Clarkson Street (1898) : For the destitute sick of Kings County. There is a separate pavilion for patients suffering from The building for consumptives is of brick, three stories high, fireproof, with baths, sun rooms, and dormitories on each floor. The hospital is a city institution. There are no charges. Ph3'sicians in charge for November and December, 1904: Drs. T. P. Corbally, T. A. McGoldrick, A. A. Rutz and P. J. York; there are always four physicians in charge, serving for terms of two months. Tuberculous patients are received in all stages of the disease and are treated in separate wards. The capacity of these wards is about one-sixth the total capacity o£ the hospital. The hospital is under the charge of the Sisters of the Poor of St. Francis. The Poor Farm, on which this hospital is situated, consists of 156 acres just within the city Hmits, at an altitude of about 600 feet. The building for consumptives is an isolated one of stone, connected with the main hospital by corridors, and containing six wards, four single rooms, and four sun rooms. It is supported jointly by the City of Buffalo and by Erie County. The hospital is for the care of the poor of Westchester County, whatever their disease; cases of contagion only are excluded. A brick building cc'ntaining two general wards, three isolation rooms, and sun parlors, has just been erected, for the separation of the tuberculous patients. Capacity of the new building: 24. House Physician : Fred Baker, M. D. All the beds are free to persons committed by the Poor Master or Commissioner of Charities. In case of vacancies pay patients will be received at the rate of $7 per week. Henry Hun and Arthur G. Root, of Albany. The architect's plans contemplate two long dormitories on each side of an administration building. At present the central building, containing offices, dining-room, assembly rooms, and apartments for the resident staff, is completed, and two of the dormitories. In each dormitory there are twenty-five bedrooms, a sitting-room, a sun parlor, nurses' apartments, diet kitchen and bathrooms. The location is near the lake, among the pine woods. Instruction in the ordinary school branches is provided for the children. The funds for building and maintenance are derived entirely from voluntary contributions. Lake Kushaqua is in Franklin County, nine miles from Paul Smith's, on the Adirondack Division of the New York Central and Hudson River Railroad. sanatorium. Two miles from the village of Liberty, on the southern slope of a range of hills, at an altitude of 2,300 feet, are located the buildings which constitute Loomis Sanatorium. The administration building is of stone and half timber, heated by steam and hot water, lighted by electricity, and containing, besides the offices, reception rooms, and dining hall, a laboratory and a number of rooms equipped for different kinds of treatment. There is an infirmary for the treatment of patients more advanced with the disease or temporarily confined to bed. The patients are housed in fourteen cottages, of varying size, scattered over the grounds. There are several cottages adapted for independent housekeeping, which may be taken by a patient and his family, enabling them thus to live apart while at the same time under sanatorium care and regime. For the consumptives of Xew York City who are without resources to procure suitable private treatment; all stages of the disease are received, and the advanced cases isolated. The history of the Tuberculosis Infirmary on Blackwell's Island is of sufficient interest to justify the following quotations from the Annual Report of the Department of Public Charities of the City of New York, for the year 1902 : "On January i, 1902, there was no hospital set apart for consumptives in the Department, though there were 318 consimiptive patients in Bellevue, City, ^Metropolitan and Almshouse Hospitals, of Avhom 155 were distributed through wards occupied by other patients, while 163 were in wards devoted to this disease, but in the same buildings as wards occupied by other patients. On Blackwell's Island, near the ^Metropolitan Hospital, there were three buildings formerly occupied by the Manhattan State Hospital for the Insane, but vacated by that hospital in October, 1901. On January 31, 1902, one of these buildings was opened as a hospital for consumptives, and within a week all consumptive patients not in wards set apart exclusively for consumptives were transferred from Bellevue, Cit}' and ]\Ietropolitan Hospitals to this new hospital. A second building was subsequently put in order by this Department through its own labor, the bars being removed from the windows, the gratings removed from over the doors, the walls painted, new floors laid and the buildings otherwise made fit for habitation, and as rapidly as the buildings could be put in order the phthisis patients were removed from the former phthisis vv-ards in the Metropolitan main building and at the Almshouse. All phthisis patients received by the Department subsequent to the opening of this hospital were sent there directly." "The Deputy Superintendent of the 2\Ietropolitan Hospital was . . . assigned to the Tuberculosis Infirmary, with instructions to give special attention to personal acquaintance with the The building for women has room for 90 patients. The men's building is much larger and consists of wide, light halls with rooms for one and two beds opening off them. There are no doors between the rooms and the corridors, and the free circulation of air is thus unhindered. Tent cottages provide for 125 men and 25 women. They weie in use all through last winter. Patients who are able to work, generally about onethird of all, are assigned some definite duty. Recently a solarium has been added to the equipment. The Riverside Sanatorium is located on North Brother Island, East River, in three one-story pavilions divided into two or more wards. It is supported by the city, and is under the direct management of the Department of Health. Nazareth, 150 women and children. The wards of the hospital are generally kept filled with patients dependent on the Department of Public Charities, and the cost of their treatment is met by the city. There are also 25 or 30 private rooms for persons able to pay from $10 to $20 per week. NEW YORK regard to sanitation and ventilation. A maximum amount of sunlight and fresh air is available both in wards and in private rooms. The institution is in charge of the Sisters of Charity. There are two resident physicians, and a number of the specialists of the city are on the visiting and consulting staff. The chief source of income is the fees paid by the city, but the institution receives some funds also from private patients, voluntary contributions and endowments. Private patients should apply directly to the Superintendent of the Hospital; by others appHcation should be made to the Superintendent, Bureau of Dependent Adults, foot of East 26th Street. $5 per week; in private rooms, $10. Physician in Chief : Charles :\I. Cauldwell, M. D. Physician in Charge : Henry A\'ollner, ]M. D. Consulting Physicians : Drs. John Doming and Frank This institution covers the entire block between St. Ann's and Brook Avenue and 143d and 144th Streets. It is owned and conducted by the Roman Catholic order of The Sisters of the Poor of St. Francis. There is a garden attached to the grounds. The main building is a four-stor\- structure, facing south, with east and west wings. It is lighted by gas and heated by steam radiators. The ground floor is divided into waitingrooms, sitting-rooms, offices, examining-rooms and small wards. The three upper stories are each divided into five large wards, five small wards and a few single rooms. The chapel occupies a separate extension. In the rear of the main building, but separated from it, is a house devoted to the use of incipient and arrested cases of consumption. An average of 1,500 patients i.-- treated each year. Apart from the individual good which these consumptives may derive from hospital care the public at large is benefited by the removal of the invalids to a place where they cease to be centers of infection, and where they no longer hamper the wage-earning capacity of the remainingmembers of their families. For ten years previous to January, 1902, the House of Rest arranged for its beneficiaries to be cared for at St. Luke's Hospital. At that time the estates at Inwood were purchased and the necessary alterations begun. The primary object is to provide a refuge for incurable consumptives, but hopeful cases are not excluded. The resident staff consists of six physicians. This institution was originally a Colored Home, with an attached hospital, chiefly for chronic cases. About two years ago it was changed to a general hospital, for both white and colored. The buildings occupy an entire block on high ground in the Bronx, overlooking the East River and Long Island Sound. physicians. Montefiore Home occupies an entire block in the northwestern part of the city, near the Hudson River, and not as yet crowded with high buildings. This, and the Country Home at Bedford Station, are charities supported by the Jewish philanthropists of the city. SiiASiDi: TjiNT- Camp for children suffering from tuberculosis in bones and glands (June, 1904) : For children from three to ten years of age, suffering This experimental sanatorium, the first of its kind in' America, was established and is maintained by the New York Association for Improving the Condition of the Poor. It is located on the Coney Island shore, at Surf Avenue and Thirtylirst Street, just west of Sea Breeze, the Association's fresh-air home, and is sufficiently far removed from the amusement halls and gaieties to be undisturbed by the noise of the usual Coney Island crowd. The tent camp consists of ten rectangular tents with wooden floors, raised a sufficient distance above the ground to allow ventilation and prevent dampness. Eight of the tents are arranged in the figure of an octagon, with a board walk connecting them, enclosing a playground of sand some thirty feet wide. Four of these tents are accommodating fifty children, one is for nurses and administration, one with open sides is a playroom, and one is used for a dining-room. The dining tent is connected with a small, single-storied, wooden structure, used in part for a kitchen and pantry, and in part for a wash-room for the children. In this building there is also a small room utilized for dressing abscesses and wounds resulting from necessary operative treatment. Two smaller tents, situated at a little distance, are used, one for attendants and one as an isolation ward. The scope of the hospital is limited to the treatment of nonpulmonary tuberculosis in children from three to ten years of age. It is not expected to carry out major surgical operations, such as are often necessary in some forms of tuberculosis, nor is it feasible to make all the appliances necessary for the treatment of joint and spinal cases. It is rather intended to prevent the use of the surgeon's knife and to hasten convalescence when operations have been necessary, and to prove to the community that hygienic means may avail in some cases which otherwise would be relegated to the surgeon or considered hopeless. A New York Board of Education. It is proposed to continue this work throughout the winter, but no longer. The purpose of the Association is to make a demonstration which will induce public authorities and private organizations or individuals to establish permanent hospitals for this class of cases. The location is a broad park of undulating ground, rising gradually to Sunrise Mount (altitude 2,000 feet), which shelters the building from the north winds, and surrounded b}^ pine and spruce forests. The sanatorium consists of an administration building, surounded by cottages. A special feature is the system for heating and ventilation, by which air from outside is continually being warmed and introduced into the rooms. The entire volume of air throughout the buildings is changed in the course of five minutes. The Sisters of Mercy are in charge. Forest Leaves, is published quarterly by the Sanatorium. This hospital is maintained by the Rochester Public Health Association, as part of its work against tuberculosis. Its quarters are a building known as the Municipal Hospital, the use of which has been granted by the city authorities. It is situated in twenty-six acres of ground, and is well adapted to the purpose for which it is being used. The Working Girls' Vacation Society exists, as its name indicates, for the purpose of making suitable vacations possible for working girls who are broken down in health. The two houses at Santa Clara are used for those who have tubercular tendencies or are already in the first stages of the disease. The length of stay is determined by the examining physician. In the summer of 1903 it averaged over five weeks for the 120 girls cared for. Santa Clara is located in the Adirondacks, 40 miles northwest of Saranac, on the New York and Ottawa Railroad, at an altitude of 1,800 feet. The vacation houses are open from June I to November i. per week and who are in the very early stages of pulmonary tuberculosis or are at least favorable types. Capacity: 100; 112 in summer, by the use of tents. The uniform charge is $5 per week; there is a free bed C. Twitchell, M. D. From a one-room cottage heated by a wood stove and lighted by a kerosene lamp Adirondack Cottage Sanitarium has grown to a small village of twenty-five or more buildings — the main building, twenty-one cottages, an infirmary, a pavilion, a chapel, a library, and a post-office — situated in the Adirondacks, a mile from Saranac Lake, at an altitude of 1,650 feet. In the first years of the existence of this sanatorium it was a problem to induce patients to go to it and to stay. Now not one in twenty of the applicants can be received, and the waiting list of successful applicants is usually long. For the benefit of persons who are attracted to Saranac Lake, either in the hope of gaining admission to the sanatorium or through confidence in the climate, two unusual accessories have been developed. A Bureau of Information is maintained in the village, for the purpose of advising strangers, and helping them to find boardingplaces, and an Out-Patient Department has, for over three years, given free medical advice to patients on the waiting list and to unsuccessful applicants for admission who cannot afford to pay for medical treatment. An attempt is made, through the Cooperative Employment Bureau conducted by the institution, to find suitable work in healthful regions for patients when they leave. A monthly magazine. The Outdoor Life, is pviblished at the sanatorium. The uniform fee of five dollars per week does not cover much more than half the cost of maintenance. The deficit is made up by gifts and subscriptions. From the beginning the summer residents have been an important source of contributions. Application should be made to any of the following physicians : Dr. Lawrason Brown, Saranac Lake ; Dr. James Alexander Miller, New York City: Dr. Linsly Williams, New York City. For "tuberculous patients who come with the expectation of admission to the sanitarium, but because of acute or advanced ilhiess are refused admission and are unable to receive suitable care at a cost within their means." This is a house maintained chiefly by Miss Mary R. Prescott, of New Bedford, Massachusetts. The fee charged is almost $5 less per week than the actual average cost of maintenance. The building occupied at present is a three-story modern dwelling, rented from year to year and not well adapted for hospital purposes. A new building for fifteen patients has just been completed and will be occupied January i, 1905. Admission is not granted by letter ; patients must be in Saranac Lake village at the time of application, which should be made to Dr. Edward R. Baldwin. There is no physician in residence, but the visiting staff consists of Drs. E. L. Trudeau, E. R. Baldwin, Charles C. Trembly and Lawrason Brown ; Mrs. Josephine R. Raymond, who is in charge, is a trained nurse with ten years' experience in the care of tuberculosis cases The location is the southwestern slope of Mt. Pisgah, threequarters of a mile from the post office, and 100 feet above the village. In the main building there are eight bed-rooms for patients and in a smaller building, four. Three tents are usedThere are well-protected porches, and a sun parlor 24 feet; by 10. nursing. There is no resident physician ; Miss Rumanapp is a trained nurse, and the visiting staff consists of Drs. Brown, Twitchell, Baldwin, Trembly and Kinghorn. In January, 1900, the Winyah Sanitarium took possession of a new establishment. The site "is a wooded park of 20 acres, well sheltered, and just outside the limits of the city of Asheville, so far removed from the center of the town as to be free from noise and dust, and yet of easy access by a branch of the Asheville electric street-car system, which passes directly through the grounds." The buildings "consist of a main structure, a large annex, and two cottages, all connected by glass-enclosed steam-heated porches and passages." There are piazzas with exposure in all directions, some of them enclosed in glass with movable windows. In addition to the indirect method of steam heating extending to all parts, there is also an open fireplace in each room. The lighting is by electricity; the water supply is from an artesian well. A laboratory for clinical work and for scientific research is a feature of the ec[uipment, also special departments for laryngology and for physical and electro-therapeutics. at liberty to send patients to the sanitarium. At present there is one building, with a wide veranda, surrounded by a shaded lawn. A new equipment, more complete and extensive, is planned. The sanitarium is in charge of the Sisters of Mercy, to whom application for admission should be made. Here is an attempt to provide for a few of the many persons who go to Asheville for the sake of the climate, but have little or no money with which to meet the expenses of board and treatment after they arrive. The price charged for board does not cover expense of maintenance, and the deficit is made up through the efforts of Mrs. M. Franklin Mallory, the founder and manager of the Home. Each patient is required to do some regular daily work, unless his physician advises against it. The "Home" is situated on the western slope of the Blue Ridge, twelve miles east of Asheville, at an altitude of about 2,400 feet. At present it consists of a twenty-room, two-story house, on a farm of 200 acres. Shack tents are being erected in the pine groves on the grounds, and by means of these the accommodations can be increased almost indefinitely. Resident Medical Director: Louis Fielding High, M. D. Southern Pines is about 100 miles from the coast, in the sandy, turpentine pine belt which extends south to Florida, and has an altitude of 700 feet. The sanitarium is a large building on a western slope, in the suburbs. Most of the bedrooms are heated by open fire-places and all have large windows, some as many as six. A wide veranda extends around the building, with ;i sun-parlor on the first floor. In this climate life in the open air is attractive at all seasons. Modern facilities for scientific hydrotherapy have recently been added. Thirty-five thousand dollars was appropriated by the legislature in 1904, to begin work on a state sanatorium. It is hoped that this initial sum will suffice for the purchase of land and for the preparation of architect's plans, and that an appropriation for construction and equipment will be made during the legislative session, 1904-1905. (See pages 246, 247.) is B. F. Tyle, M. D. This is a city institution, but it is situated outside of the city in its own grounds of 52 acres. The altitude is 850 feet. The main buildings consist of nine wards ; the solarium has one large ward and five private rooms ; tents are used, also, in whatever number is required. The Sanatorium is one building two stories high and 200 feet in length, situated 600 feet from any other building, on the brow of a hill overlooking the city. There are four wards and sixteen private rooms, and twelve-foot porches on three sides of the building. DAYTON. The Miami Vaij.ky Hospital has, for two years, reserved for consumptives a small isolation building, with accommodations for three patients. These beds are free. One tent also is used. There are two resident physicians in the Hospital. The Hospital is located on an eighty-acre plot 900 feet above sea level, near the Ohio River. There are twelve specially constructed cottages arranged in a semi-circle on the crest of a hill and separated from one another by a ten-foot space ; also other cottages for diet kitchen and nurses. All the buildings have adjustable glass roofs and verandas extending entirely around. Attempts to secure the establishment of a state sanatorium have been made at various times by the Pennsylvania Society for the Prevention of Tuberculosis, but they have not been successful. The state contributes, however, to the support of certain private institutions. Resident Physician : Albert S. Ashmead, M. D. The Camp is situated in the Pocono Mountains at an altitude of 2,000 feet. Each patient has his own tent or wooden chalet, facing east, as the storms are generally from the northwest. Greentown is reached by stage from Gouldsboro, the nearest railroad station, which is on the Delaware, Lackawanna and Western Railroad. During the first summer of its existence this sanatorium has consisted of a tent camp on the top of Sharp Mountain, 1,600 feet above sea level. It is the intention to erect dormitories and administration buildings for winter use. The institution is designed to meet the needs of that large class of consumptives who are able to pay a moderate fee for treatment, but not the ordinary sanatorium prices. cians are easily accessible. This is, as its name indicates, merely a camp in the woods. Its existence is due to the interest and initiative of Dr. Rothrock, the State Commissioner of Forestry. The land and buildings are state property. All that the state furnishes, however, is ''shelter, fuel, air, and water." Campers are expected to make their own arrangements about food and other provisions. There are eleven plain board cabins, ten feet square, intended for two men each, and seven cottages for women, each with two rooms and a small kitchen. Cots and stoves are the only furniture provided. A large assembly building has been erected for the use of all. From the beginning the number of applications has far exceeded the accommodations, in spite of the slight attractions offered and the strict enforcement of certain rules in the camp. A private sanatorium, intended to be a comfortable home for about ten patients, will be opened, in the summer of 1005, within half a mile of the South Mountain Camp Sanatorium, by Drs. J. T. and A. M. Rothrock. For ten years the consumptives have been isolated in wards. New buildings have just been constructed, especially designed for the treatment of tuberculosis. They include a hospital of 66 beds and six pavilions made entirely of glass and steel, each accommodating 18. These buildings are on the highest part of the hospital grounds, not far from the river. During the summer of 1903 the hospital roof was converted into a ward where as many as possible of the patients in the earlier stages of consumption were kept night and day. For women unable to pay for proper treatment ; all stages of pulmonary tuberculosis are received, and cases of bronchitis, but most of the patients are consumptives in an advanced stage. There are no fixed charges, but patients and their friends are expected to contribute, according to their means, toward the support of the hospital. Visiting Physicians : Drs. Wm. M. Angney, Charles A. Currie, J. Clinton Foltz, Myer Solis Cohen ; Arthur W. Watson, laryngologist ; Robert L. Pitfield, bacteriologist. PENNSYLVANIA sion in 1876, and were the first institutions in Pennsylvania especially for consumptives. More than 3,500 patients have been cared for by this organization, either at home or in the hospital. No distinction is made on account of nationality, creed, or color. At Chestnut Hill buildings designed especially as a hospital for consumptives have been erected. They are located on an elevated piece of ground, 500 feet above tide water, one of the highest points near Philadelphia. There are four hospital buildings and one administration building. The institution is conducted on the separate principle, each patient having her own room. All bedrooms face due south. Two of the hospital buildings have been furnished with wide open porches, on which the beds of the patients are placed. In stormy weather heavy awnings are dropped to the floor. The fresh-air treatment has been in force for nearly ten years. In the summer of 1903 tent life was introduced; this was tried again in 1904, and in both years was continued until high winter winds rendered the tents insecure. House Physician : William Muir Angney, M. D. Almost all of the patients here are advanced cases. They are cared for in four small wards in a city house. A roof garden is used for open-air treatment. This institution is maintained by the Protestant Episcopal City Mission. ( See page 121 ) . and tents. A larger city hospital, with provision for at least 80 patients, is now building. The institution is supported by a state endowment, fees from patients, and voluntary contributions. The; Dermady Sanatorium, Gowen Avenue and Sprague Street, Mt. Airy (June i, 1904) : Exclusively for pulmonary tuberculosis. Capacity : 25. There is no resident physician ; patients can have the advice of Drs. Lawrence F. Flick, William B. Stanton, Joseph Walsh, D. J. McCarthy, H. M. B. Landis, and Charles Hatfield. This sanatorium is twelve miles from Philadelphia, at an altitude of 500 feet. The main building is a three-story house of gray stone, and the annex, which will accommodate twelve patients, is a smaller building, of stone and wood. Over two acres of wooded lawn surround the houses. Graduate nurses and a graduate in hydrotherapy are in attendance. Any physician may place and treat patients in this institution. An association has been formed by prominent citizens of Pittsburg for organized and systematic work among the consumptive poor of the city. The first efforts will be directed toward establishing a free hospital. Four acres of land on a hill in the city, with buildings easily adaptable to the requirements of a hospital, have been given for the purpose. The altitude is about 1,200 feet, and the buildings command a view of the Allegheny and Ohio River valleys. of six. This institution is located on a sixty-acre farm, just outside the city limits, on a mountain side, at an elevation of 1,600 feet. It is expected that when the land is fully developed it will furnish all the milk, eggs, and garden produce needed. Patients able to work are required to do so. The hospital building has two wards of ten beds each, and is heated by steam. There are also four shacks for two patients each, which can be used all winter ; nine others for summer ; a farmhouse, a barn and a laundry. The funds for construction and maintenance are derived wholly from voluntary contributions, the fees from patients being practically a negligible amount. The sanatorium was established and is maintained by the Scranton Society for the Prevention and Cure of Consumption (see page 250). altitude of about 1,500 feet. The Hospital was founded in 1895, but for the first six years its beneficiaries were boarded in existing institutions. The nucleus of the present equipment was a barn, which in 1901 was transformed into a pavilion accommodating sixty patients. There have been built, since, three cottages, wath a capacity of sixteen each. An administration building and superintendent's quarters are almost ready for occupancy. in the village. Visiting staff: Drs. Lawrence F. Flick, Joseph AA^alsh,. \Vm. B. Stanton, Henry ^L Xeale, Chas. J. Hatfield, N. M. R. Landis, D. A. McCarthy, A. M. Shoem.^.ker. This private sanatorium is situated among the mountains, overlooking the Lehigh Valley, 1,200 feet above sea level. The soil is dry, porous shale. The main building contains administration of^ces and twelve bedrooms. There are also three cottages and a central dining hall, and from April to November tents are used. something. There will be resident physicians. The buildings, which were completed in the spring of 1904^ consist of a three-story administration building, connected by covered corridors with a two-story pavilion on each side. The site, near Wallum Pond in the extreme northwestern part of the state, has an elevation of about 600 feet. It is expected that the state will assume one-half the expense of support, the other half to be borne by the patient. Street, Providence. A physician is in residence during the summer, and there is a large consulting and visiting stafif ; both men and women nurses are always in attendance. A New England farm of 50 acres is the site of this camp. It has a southern exposure, is almost surrounded by pine forests, and has an altitude of 600 feet. The soil is porous ; there is spring water on the place, and trout streams and hunting near. The plant consists of an administration building of rough boards, ten cabins 10 by 12 feet, accommodating two patients each, a separate kitchen and dining-room, and twentytwo tents. Abandoned trolley cars have also been pressed into service, and transformed into bed-rooms, one patient in each,. as a step toward solving the problem of economy. Physician in Charge : George F. Keene, M. D. For eight years the tuberculous patients in this institution have been cared for in a separate building. There are two long wards, one for men and one for women. Patients are kept out of doors as much as possible. advancement are admitted. Capacity of the tuberculosis wards : 24. The hospital is primarily for the poor ; if a patient is able to do so he pays a small sum, never more than $7 per week. The hospital is a six-story brick building, situated on a slight elevation in a residence district of the city. Its chief source of support is voluntary contributions. The Aiken Cottages originated with a group of Massachusetts men and women who were impressed with the need of some place where yovmg men attracted to Aiken by the climate, but friendless and unable to pay for proper care, might find a chance for health. Of the eight directors, four are residents of Massachusetts, so that it is largely a New England enterprise. Aiken is a small village located on a sand ridge running from east to west across the state. The sanatorium is at the western edge of the town, on the highest point of ground, at an altitude of 565 feet. Artesian wells, sunk to a depth of 800 feet, supply the water. The main building contains the administration offices, general rooms and bedrooms for seven patients. A smaller cottage, accommodating four, has been added; and recently two tents, for two men each. Each patient has his own room, but sleeps on the piazza outside. The aim of the founders and directors has been from the beginning to keep the characteristics of a home rather than of an institution. There were 25 residents in February, 1904. Terms : $1 per day ; $25 per month. Manager and owner : C. H. Wilkinson, M. D. Camp Reliance is pitched near the Guadeloupe River, on the summit of a hill, two miles from the German village of Kendall. There is a flag station at the Camp for the benefit of residents. The elevation is 1,700 feet. In the main building, 70 by 40 feet, are the dining-room, parlors and baths. The bed-rooms are tents, well ventilated and built on floors six inches above the ground. The hospital is situated on a hill in the residence portion of the town. It is a five-story brick structure, heated by steam, lighted by gas and electricity. The Sisters of Charity are in charge. The State Tuberculosis Commission (see page 251) is requested to incorporate in its report to the legislature recommendations in regard to sanatorium provision ; and the State Society for the Prevention of Tuberculosis (see page 252) will use all its influence to support such recommendations. All beds are free. Superintendent :William P. O'Rourke, M. D. The tents are located on the grounds of the County Hospital, four miles from Seattle, in the Valley of the Duwamish River. They are so constructed that the canvas forming both the roof and the side walls can be raised and lowered, as sun or wind dictate. All the tents are supplied with hot and cold water. Patients are given five meals daily, and all their eating utensils are kept separate. Capacity: 12, in cottages. Terms : $15 per week in cottages ; persons unable to meet this expense are allowed to build their own shacks or pitch tents on the grounds, provided they comply with the same regulations as the regular patients, and are given medical attendance at the rate of $10 per month. The sanatorium is open from May i to November i. It is thirty miles from Lake Superior, on the Duluth, South Shore and Atlantic Railroad, in the extreme northwest of the state, and the altitude is 1,106 feet. The cottages are situated on a gentle slope of sandy soil facing southwest. They are so constructed that the occupants practically sleep out of doors, and all are required to be in the sunshine all day. The life is simple and informal, but implicit obedience to the general sanitary regulations and to the individual advice of physician and nurses is insisted upon. TOMAHAWK, Lincoln County. The Wisconsin Health Park Association was organized in ]\Iarch, 1902, "to establish and maintain a Health Park or Parks in northern Wisconsin where invalids (especially incipient cases of tuberculosis) may be sent for improvement and recovery." A tract of 240 acres, chiefly pine-covered hills, at Tomahawk, in Lincoln County, has been donated, and the work of clearing parts of it for cultivation and for the erection of cottages has been begun. The plan is to provide for all who wish to go to it, giving to those with limited means an opportunity to pay for their maintenance by working a few hours a day. It is expected that a few patients can be received in the spring of 1905. The funds for the work of the Association are derived entirely from voluntary contributions. Over three hundred and fifty men and women of Wisconsin are enrolled as members. This is a charitable enterprise ; none of the officers receives any pay and all the gifts are used to improve the land. A site has been secured at Kentville, on a bluff 250 feet above sea level, and open to the south and southwest. The first building will be two stories high and will contain 18 rooms for patients, general rooms, sun-parlors, apartments for officers and staff. It is hoped that it will be ready for occupancy this summer. The sanatorium consists of two cottages, connected bv a solarium, and supplied on the west, north and south with verandas, some of which are enclosed. It is on the Wolfville Ridge, a spur of the South Mountain, and has an altitude of 300 feet. The sanatorium was established through gifts from individuals and from the town of Gravenhurst. Funds for maintenance are supplied by the fees from patients and a small grant of $2,000 from the provincial government. It is situated in a wooded park of 50 acres, sheltered on the north and northwest by rocky ridges and pine forests. Toward the south and southwest it overlooks the southern arm of Lake Muskoka. The district is rocky ; the soil porous and dry. The mean relative humidity is 70 to 75 and the mean annual temperature is 42 degrees. There is a central building which contains, besides the offices, reception and dining-rooms, and three solaria, accommodations for 27 patients ; the other buildings are five cottages, with an aggregate of 28 beds, and ten roofed tents for two patients each. The buildings face southwest, are lighted by electricity and heated by steam and hot water. The interior finish is hard wood, with rounded corners. The walls are either cement plaster or are painted. Both Muskoka Cottage Sanatorium and the Free Hospital at Gravenhurst were established by and are under the direction of the National Sanitarium Association. Treatment is entirely free to those who cannot afford to pay ; any contribution that a patient is able to make is accepted, but this is rarely more than three or four dollars a week. This, the second institution established by the National Sanitarium Association, has the same advantages of climate and general situation as the Muskoka Cottage Sanatorium. Its most important source of income is voluntary contributions ; it is subsidized by the provincial government to the amount of &1.50 per week for each patient; subscriptions are made by patients and municipalities ; and there is a small endowment. The administration building has room for 47 patients ; there are four roofed tents for four patients each ; and a pavilion for twelve. The lighting is by electricity, the heating by steam and hot water. Patients who are considered physically able have been given light work to do, either in the house or out of doors. It has been the aim to give work to graduate patients, who, being unable to remain longer as patients, are thus enabled to prolong their life under sanatorium conditions, and at the same time become self-supporting. A small poultry-breeding plant has been started, and it is proposed to keep pigs and start a vegetable garden as soon as funds are available. stages will not be refused. Capacity : 50 at present ; to be increased to 100. There is no charge for patients who cannot afford to pay. Resident Physician : Dr. Allan Adams, B. A. Forty acres of wooded land on the bank of. the Humber River are the site of this new hospital. The management is in the hands of a Trust Board, of which the chairman is Mr. W. j. Gage, to whom the National Sanitarium Association, with its two Muskoka institutions, largely owes its existence and growth. The buildings include an administration building, pavilions, and roofed tents. It will be supported mainly by voluntary contributions. jected. A grant of 500 acres of land, in Trembling Mountain Park, has been made by the Government to the Montreal League, for the erection of the necessary buildings. The Park of which this land is a part is a natural preserve of 100,000 acres, enclosing many lakes and mountains. The site of the projected sanatorium is at the entrance to the Park. Physician in charge : Howard D. Kemp, M. D. Lahl Ghur, The Red House, is a private sanatorium, situated at Ste. Agathe, on a gentle slope, at an elevation of about 1,300 feet. The buildings, facing south, are three semi-detached cottages, with a central dining-room and sitting rooms. There are electric lights throughout, hot and cold baths, hot water heating, and long distance telephones. Veranda life is provided for throughout the year. DISPEXSARIES FOR TUBERCULOSIS Dispensaries exclusively devoted to the treatment and care of tuberculous patients are of recent origin, one of the first having been established by Calmette, of Lille, France, whose work and aims still stand as a model and inspiration to those contemplating similar enterprises. Since that time many such establishments have sprung up on the continent of Europe as well as in this country. All, however, are agreed that its scope should be wider than that of an ordinary clinic or out-patient department. The majority of such institutions on the continent are independent establishments and occupy separate buildings, while in England the consumptive hospitals have out-patient departments which may be considered, in a general sense, to be tuberculosis dispensaries. Heretofore, in this country at least, it has always been the custom, and for the most part is now, to treat tuberculous patients in the general medical clinics, and only from a medical standpoint. They were examined more or less thoroughly and prescribed for, the attention devoted to them depending on the interest of the physician in the patient and his disease and the time at his command. It is obvious that, in a large medical clinic, a tuberculous patient could receive but scant attention. With the great interest and activity in the relief and control of tuberculosis now existing, and the recognition of what can be accomplished in the way of prevention and the curability of the disease, every additional measure calculated to further these objects is to be commended, and from what it has already accomplished in the short time of its existence the anti-tuberculosis dispensary has proved itself to be an exceedingly valuable addition to one's armamentarium in the tuberculosis warfare, and has abundantly justified its existence. The role of the anti-tuberculosis dispensary, as formulated by the French, is threefold : prophylactic, therapeutic and social ; under social being included material aid to the poor consumptive on the one hand, and protection of the public from the SPECIAL DISPENSARIES disease on the other. By instruction of the patient as to the proper disposal of his sputum and in regard to disinfection, by showing in simple language how to avoid contracting the disease, that it is curable, and in what way, one fulfils the prophylactic role. The therapeutic role is fulfilled by the more directly medical treatment of the patient, the diagnosis, prognosis, and the prescription of any drug that is considered necessary. The social role comprises personal investigation of the patient and his home by a special visitor or trained nurses, providing proper food when necessary, and in other ways supplying the material wants of the patient as the emergency of the special case demands. This latter role — the social — is carried out, at least in this country, by associations already established in a number of cities for the prevention, relief and control of tuberculosis, and such associations work in close touch with the anti-tuberculosis dispensary. Further, they assist the patient in being admitted to the sanatorium when the case is a curable one, or mto a consumptives' hospital when it is too far advanced to enter a sanatorium ; and, through the instrumentality of the board of health, when a patient becomes a menace to the other members of his household, they see that he is removed to some institution. There are advantages in having a tuberculosis clinic under the same roof with a general dispensary, as well as in devoting a special building to it as is done in France and elsewhere. In tlie former case it is easier, for instance, to refer to other departments for advice and examination, to the laryngological, the X-ray, or general medical department, for example ; and other departments can, in their turn, refer cases to the tuberculosis room for an opinion or examination. The expense, moreover, is far less, for this is under the same administration with the other clinics, and all the machinery of the general dispensary can be utilized, so that to establish a tuberculosis department in an already existing dispensary a staff of physicians has only to be appointed and one or several rooms set apart for the purpose. snd even a 'single room can be made to do. House visitation through a special visitor or district nurses can as well be conducted from a department of this kind as from a special establishment. Such is the plan of operation at the Boston dispensary, and it has worked successfully. importance of the cure and control of the disease, and lends dignity to the work. Moreover, larger facilities can be afforded in increased room, and the construction of the building can be especially directed to the treatment of this one disease. Ventilation, disinfection, special methods of treatment, can all receive careful consideration ; more ample facilities for laboratory work can also be offered in the way of animal experimentation, bacteriology, and other lines of special research. In such a building an ofifice for the visitor or district nurse would find a place. Another room might be devoted to the exhibition of various material bearing upon the causes, prevention and cure of tuberculosis, such as photographs of unsanitary tenement-houses and bed-rooms, statistics graphically illustrated, methods of obtaining fresh air and devices for utilizing existing conditions for the same, models of tents, photographs of sanatoriums, and very many other exhibits, as will readily suggest themselves. In a large city one or more special tuberculosis dispensaries on this extensive scale might become of inestimable value as a great anti-tuberculosis center. The simplest equipment of the tuberculosis dispensary should consist of a separate waiting-room and receiving or consultingroom v/here histories are taken, together with the pulse, temperature, respiration and weight ; several small examining rooms ; a small room for the examination of the sputum and other bacteriological investigations ; a dark room for laryngoscopic examination, unless a throat department exists in the same building ; and, possibly, an X-ray room. Rooms should be well ventilated and periodically disinfected. . Circumstances would determine the arrangement of the personnel of the staff', but as the careful examination of the consumptive requires considerable time, there should at least be several skilled assistants while the clinic is going on. perience and thought would suggest the following: (i) As complete an investigation of the patient as possible, including history, physical and bacteriological examination, and when the diagnosis is doubtful, the tuberculin test and an X-ray examination. spittoons. (5 J Securing entrajice into sanatoriums for curable cases, and into consumptives" hospitals for incurable ones when they cannot be properly treated at home ; or, when neither is possible, to treat the patient at his home as well as the conditions will permit. examination of tuberculous patients. Of course, as has been mentioned above, some of these objects are already fulfilled b}^ tlie existing associations for the relief and control of tuberculosis. They investigate the patient and his home ; the}' supply him with food and other needed articles, and obtain mone}' with which to send him to a sanatorium or hospital. And the association of this nature in Boston, at least, is proposing to investigate and look after those patients discharged from the state hospital for consumptives at Rutland. After an experience of several years with such a clinic, the writer is profoundly impressed with the great good that can be accomplished by it, and believes that the time will come when entirely separate establishments of this kind will be founded in every large city and that they will play no insignificant part in the general crusade against consumption. Xorth Broadway : A new building devoted to the tuberculosis work of the out-patient department has been made possible by a gift of S20,ooo from Henry Phipps, of Pittsburgh. The plans for this building contemplate a class room and small examining rooms en the first floor, with a library and special work rooms above. A special medical officer will be detailed for service, and a nurse to look after the patients in their homes. Children and adults are treated in separate classes. There are no nurses especially for consumptives, but the fourteen district nurses visit such cases as w^ell as other patients. Dr. Otis has three assistants in the Tuberculosis Clinic, and there are district physicians to treat patients not able to go to the dispensary. Printed instructions are given to patients and it is planned to supply sputum cups for use at home. Of the 29,438 new patients in the dispensary last year 275 were treated in the Tuberculosis Clinic. Secretary, Caroline Hedger, M. D. There is a physician in charge of each district office, a general consulting stafif of seventeen members, and nineteen nurses for visiting the homes. Advice is free. The Tuberculosis Committee has established, in co-operation with the Bureau of Charities, a special district service for poor tuberculosis patients. In the district offices of the Bureau of CHICAGO Charities rooms are set aside and utilized by the district physicians as consultation offices. Every case of manifest or suspected tuberculosis coming to the notice of the committee or the lelief agencies associated with it is referred to the office of the district in which he resides. Then the patient is visited at home by either a charity worker or one of the district nurses, for the purpose of ascertaining the patient's condition and that of his home, of which a report is made to the district physician. The patient is also instructed as to sputum disposal, general hygiene and similar matters. All patients able to be out of bed are then sent to the district office, where at fixed hours they are seen by the physician in charge, who examines and advises them. He also visits bed-ridden patients in their homes and directs the nurses as to special requirements. He reports each case and makes recommendations to the central office in regard to removal to hospital, transportation, disinfection, supplies and relief. The intention of the committee is primarily to educate, through trained assistants, the patients and their families, and in this way to improve insanitary conditions in the homes. The treatment of patients is undertaken only on general lines (openair, over-feeding and specific hygienic directions) ; for special treatment patients are referred to other dispensaries. In the education of patients and their families preference is given to repeated personal interviews rather than to printed circulars. The addresses of the district offices are as follows : Central District, 1500 Wabash Avenue. South Central District, 291 East Thirty-first Street. Stock Yards District, 716 West Forty-seventh Place. Woodlawn District, 337 East Sixty-third Street. Englewood District, 333 West Sixty-third Street. West Side District, 181 West Madison Street. Northwestern District, 1235 Milwaukee Avenue. Ravenswood District, Foster Avenue and E. Ravenswood Park. North Shore District, Foster Avenue and E. Ravenswood Park. Northern District, 1140 North Halsted Street. Lower North District, 365 Wells Street. Southwest District, 946 South Ashland Avenue. when medicines are needed. The entire time of one nurse is available for visiting patients in their homes, and part of the time of several others. Sputum cups and pocket flasks are supplied, and printed as well as oral instructions are given. By co-operation with the Tuberculosis Department of the Associated Charities it is possible to send a nurse to the home. Printed instructions are supplied and sputum receptacles for the pocket and for use at home. Twenty patients were treated in the special clinic in the first six months of its existence. In the first ten months of the special clinic for tuberculosis fifty patients were treated. By co-operation with the Tuberculosis Department of the Associated Charities, sputum cups and printed instructions are provided and a nurse is available for visiting patients in their homes. The Associated Charities, in turn, can secure from this dispensary an expert diagnosis in all doubtful cases coming to their attention. There is a wellequipped laboratory for bacteriological and experimental work. In addition to the usual clinical history of the patients information in regard to their social and industrial conditions is recorded. MONTREAL, Canada. A Special Dispensary for the treatment of tuberculosis was opened on Xovember 2, 1904, by the Montreal League for the Prevention of Tuberculosis (see page 254) at 691 Dorchester Street. Three physicians are in attendance. Foods, as well as medicines, will be supplied free of charge, and visits will be made to the patients in their homes. There is no charge for advice. The special clinic was established in the fall of 1903. Printed instructions are given to patients and sputum cups are provided. There is as yet no visiting nurse, but it is planned to develop the department as rapidly as possible, until it shall include all the features recognized as desirable. Advice and medicine are free. The Municipal Clinic is housed in a new building especially designed for the purpose, adjoining the headquarters of the Department. The building contains a registration room, drug room, two waiting rooms, an X-ra}^ room, throat department, and two clinic rooms, for male and female patients, respectively, each with its examination room. Physical examination, repeated sputum examinations and, when required. X-ray examination, may all be used in making the diagnosis, in order to guard against missing incipient cases. Instructions, both verbal and by means of circulars printed in nine or ten languages, are given as to the nature of the disease, and the necessary personal and hygienic precautions to be taken to prevent the infection of others. Paper sputum cups are supplied to needy cases. A special staff of trained nurses visits the patients at their homes to see that the instructions are being observed, that the sanitary surroundings are satisfactory, and that such assistance is given as is required. Suitable cases are referred to charitable organizations for assistance. Every effort is made to prevent the infection of the children in the family and to bring about the removal tO' hospitals or sanatoriums of the dispensary patients who require such care. Double reference cards, one-half to be filled out and given to the patient, the other to be sent to the Department of Health bearing the patient's name and address, are furnished to physicians, charitable organizations, or any one else who has occasion to use them. If the patient does not report within a given time he is visited from the dispensary. Nurse in charge : Miss Annie Damer. The proper regulation of the home conditions is especially emphasized. Two visiting nurses are attached to the clinic and close co-operation with the physicians and with relief societies is obtained. Milk and eggs are given, as a part of the treatment, after thorough investigation has established the need of such assistance. Printed instructions and sputum cups are distributed. In some instances reclining chairs and sleeping bags are given for open-air treatment on the roofs and fire-escapes. Tent cottages have been erected upon the hospital grounds for favorable cases who cannot obtain suitable sanatorium or home treatment. About fifty new cases are received each month. The total number of cases treated since the opening of the clinic (ten months) is 440. Special class for tuberculous patients. Monday, Wednesday and Friday, 11 to i. Clinical assistants in charge of tuberculosis work ; Stella During the first five months of this special class the average number of patients per month was 13. During September, 1904, 85 patients were treated, 30 of whom were new. Simple verbal advice is given. Sputum cups are supplied for use at home. Since June the work in the clinic has been supplemented by the services of a visiting nurse. The special class here has just been started, and the organization is not yet complete. Verbal instructions only are given, and there is no arrangement for visiting patients in their homes. In the first six weeks after the opening of the special clinic about fifty tuberculous patients were treated. Dr. Russell accepts for treatment adults in any stage of pulmonary tuberculosis, provided it is imcomplicated with any other disease, and provided the patients are able to go to the dispensary twice a day and to secure suitable food, clothing and shelter. During 1903 there were treated in this class 74 cases ; in the first nine months of 1904, 62. The treatment consists largely of careful questioning and advice in regard to food, sleep, and general habits of life. The Russell Emulsion of mixed fats is administered at the dispensary. Each patient is required to report at the dispensary twice each day, and the hours are arranged for the convenience of working men and women. Irregularity of attendance or failure to obey directions is followed by dismissal from the class. Physicians of the city are invited to send suitable cases and to visit the class any' Sunday morning at nine. Reports of the results obtained are published annually in the Post-Graduate Journal, by a committee of inspection appointed by the Executive Committee of the Post-Graduate Medical School for the purpose of reviewing Dr. Russell's work. An annex to the Dispensary has just been added, in the shape of a small hospital for twelve patients in the advanced stages of the disease. The hospital is at 322 East Nineteenth Street. Eight physicians are in charge. Ten cents is collected for each prescription from those able to pay ; otherwise no charge is made. Children and adults are treated in separate classes. There are three nurses who visit patients in their homes. Printed instructions are distributed and sputum cups are supplied. During 1903 the total number of patients treated for tuberculosis was 410. and Sixtieth Street : There is no special department for tuberculous patients attending the Clinic, but for nearly two years a certain number of them have been given special attention. The work was begun by Dr. J. A. Miller, now in charge of the Tuberculosis Classes in the Out-Patient Department of Bellevue, in January of 1903, and it is now being carried on by Dr. Linsly R. AMlliams, under the supervision of Prof. James of the Department of ^Medicine. Patients are given verbal and printed instructions about the care of sputum and they also receive advice as to diet and hygiene. Sputum pouches are supplied. A special record of their clinical history is kept and a report of the home and linancial conditions. All patients in Manhattan are visited and further instructed by a nurse supplied by the Presbyterian Hospital. Patients from other boroughs are visited by the Board of Health nurses. Daily, 12 to i p. m. Chief of the Clinic : Henry A. Pulsford, M. D. Those who can afford to do so pay ten cents at their first visit : there are no other charges. The special clinic was organized April 1, 1904. One visiting nurse is attached to this department and printed instructions are distributed to patients. Advice is free. There is no provision for visiting the homes or for exercising any further influence on the patients after they have left the dispensary. About 500 patients were treated last year, A special clinic for tuberculosis was established July i, 1900. In the year ending September 30, 1903, the patients examined or treated for tuberculosis numbered 1,337, of whom 1,074 were old patients, 263 new. Three nurses, employed by the Providence District Nursing Association, visit the homes, as requested. Printed instructions and sputum cups are supplied. All patients applying in the other departments of the dispensary are referred here when they show anv indications of tuberculosis. The chief difficulties encountered are the lack of provision for patients needing sanatorium or hospital treatment, and the securing of proper nourishment at home. About one-third of the patients last year were treated for tuberculosis. Printed instructions are given to patients, sputum cups are supplied, and a nurse visits those who need special care. "Of the fifty-three consumptives" (treated in 1903), reads the first annual report of the society, "it is probable that nearly all have been so taught that they will not spread the disease to others." WASHINGTON, District of Columbia. A Free Dispensary for the examination and treatment of those who are suffering from tuberculosis or suspect that they may have contracted it has been opened by the Associated Charities' Committee on the Prevention of Consumption, at 605 Four-and-Half Street, S. W. Special diet when the patient is unable to procure it for himself, and whatever care in the home is indispensable, are provided by co-operation with the Associated Charities, the District Nurse Association and the Worcester Association for the Relief and Control of Tuberculosis. A small card folder of "rules for consumptives" is given to patients and sputum cups are supplied for use at home. Residents of Worcester County who desire admittance to the State Sanatorium are examined here. The number of patients treated in the Tuberculosis Clinic, in the first nine months after it was opened, was 46. INSANE \The illustrations which accompany this article are from the Annual Report for 1903 of the Manhattan btate Hospital, East, the use of the original plates having been kindly accorded by the General Manager of the State Printer's Office, Mr. Charles M. Winchester, Jr.) That consumptive insane patients may be kept, and treated, to their advantage and incidentally to the advantage of their fellow-inmates, in canvas tents, and throughout the several seasons of the year, has been demonstrated in the recent history of the Alanhattan State Hospital, East. The experiment upon the success of which this claim is advanced has, at the date of this writing, September 30, 1904, covered a period of forty months, the camp having been first established and occupied by patients on June 5, 1901. The serious problem of caring for this class of patients had, prior to that date, embarrassed this particular hospital with others, and with added seriousness from the fact that insane men had to be dealt with, and that the form of construction of the hospital buildings was such that no smaller wards or sections, adaptable to necessary isolation, were available. In all hospitals for the insane the form of insanitv properly constitutes the prevailing basis for classification, modified, of course, b_y such secondary considerations as the patient's physical condition, progress toward recovery or the reverse, and other elements. To set up another standard — the presence of a bodily diseased condition— and to assemble all patients suffering from it, without regard to any associated conditions or circumstances, is a difficult undertaking, involving, among other departures from routine practice, the association of disturbed and dangerous with demented and harmless patients, and so on through all the intermediate degrees. This, too, has been accomplished, and with unexpected ease and success. ]\Iy first intention and expectation were that, by possibility, the consumptive insane patients, or a majority of them, might be removed from contact with their fellows for some months, perhaps as many as five months, during the milder season of the year, with the attendant advantage of freeing, for the time being, opportunity for disinfection and renovation. Study was made of the arrangement of hospital tents and accessories in the exhibit by the United States Army Hospital Corps at the Pan-American Exposition then in progress at Buffalo, and visits were made, for the same purpose, to army posts in the vicinity of New York City. The camp first established consisted of two large dormitory tents — twenty by forty feet — each containing twenty beds, with smaller tents of different shapes, about ten by ten feet, for the accommodation of the nurses, the care of hospital stores, pantries and a dining-tent for such patients as were able to leave their beds and tents, and go to the table for their meals. Running water was secured by means of underground pipes, and the safe disposition of waste and sewage was also specially provided for. As has been said, it was expected to continue the camp only through the summer and as far into the autumn as favorable weather might render justifiable. But when in the late autumn it was found that the favorable experience continued, it was decided to attempt to carry the experiment, on a modified scale, into, or even through, the approaching winter. The Camp, as first established, had been placed upon an elevated knoll adjacent to the river side and purposely exposed to the full force of the summer breezes. For the winter experiment its site was removed to the center of the island, where trees and buildings interposed to act as a wind-break to the severe storms from the east and northeast which are tO' be expected in that locality. The number of patients was reduced to twenty, those in whom the disease was most active being retained and the others being returned, for the time being, and much against their will, to the buildings. One large tent sufliiced for the housing at night of the reduced number of patients, and one was set apart as a sitting-room for day use, with the accessory tents before mentioned,' and large stoves were placed in them, here and there, with wire screens surrounding them to protect the patients, and a liberal use of asbestos and other fireproof material and arrangements for the prevention of fire. Better resistance to the force of the expected gales was secured by stronger and more numerous guy-ropes and anchorages, and slatted wooden movable pathways were prepared which might furnish means of passage between the tents when snow and slush should come. Thus TUBERCULOUS INSANE equipped the coming of midwinter was awaited with the expectation that the twenty survivors must sooner or later follow their fellows into the shelter of the permanent buildings, and with every preparation made for immediate evacuation and retreat. The most sanguine hope did not go beyond this point. As the weeks passed, however, and the patients continued comfortable, evacuation was deferred until a severe storm occurred. Then it was found that, in spite of high wind and snow, a more equable temperature had been maintained and less discomfort caused in the tents than in the hospital wards most exposed to the force of the gale. From that experience, followed by other confirmatory ones, resulted the reconsideration of the design to evacuate the Camp. To make a long story short, it has remained in continuous use, not only throughout the first winter, but through the two succeeding winters and intervening seasons, up to the date of the present writing. The scope of its employment has been gradually enlarged until all patients in whom there are active manifestations of phthisical processes — an average of forty-three out of a total census of about two thousand — are isolated therein, and there has been parallel enlargement of the elements of the plant. While not properly coming within the scope of this writing, it may not be out of place to make brief mention of the fact that the success of the first established Camp — that for the tuberculous insane — has led to the extension of the tent treatment for the insane, at this hospital, to several other classes of patients. Following the experiences and results of the first winter, as above summarized, the tuberculosis Camp was in the spring reenlarged to its full capacity, and has remained in full use ever since, so that every patient showing the least activity of symptoms is not only afforded for himself the advantage of the outdoor treatment, but is removed from possible danger of injurious influence upon his neighbors. Each year also an additional camp for another class of the insane has been put in commission: one in 1901, Camp "B," for demented and uncleanly men, many of them bedridden, whose emancipation from the wards was a great gain, both for themselves and for the hospital conditions generally; one in 1902, Camp "C," for feeble and decrepit women, who were losing the benefits of outdoor life because the high levels and long stairways of the buildings were a prohibition to egress and ingress ; one in 1903, Camp "D," for convalescing patients, and those mainly from among the workers in the printing office, the shoe shop, and the tailor shop^ so that they might enjoy, in .the non- working hours, and tspecially at night, the advantages of which their indoor emplovments deprived them during the greater portion of the day ; and, lastly, one in 1904, Camp '■£,'' of forty beds, as an accessory to the acute hospital service, where patients for the most part confined to bed, and suffering from various concurrent diseases added to their insanity, find an agreeable and beneficial change from the ordinary surroundings of the hospital sickroom. In all, during the summer just past, and at this date, two hundred and sixty patients have been, and are. undergoing tenttreatment, an average of forty-three — all consumptives — remaining in Camp "A" throughout the year, and the others as long as favorable weather continues. In 1903 Camp "B" cont'nued in commission from Jime i to November 30, Camp "C^ from June i to October 15, Camp "D" from June i to November 30. and Camp ■'■£''" was opened on July i, 1904, and. with the several others, is still f September 30) in use. It is not proposed to follow here in detail the history of the Camp for tuberculous patients. Neither the purpose of this communication nor the lim.itation as to space will permit of it, and the reader who may desire further information in that direction must be referred to the annual printed reports of the hospital, and to special articles by members of the hospital staff which have, from lime to time, appeared in the Journal of Insanity and other professional pviblications. It must suffice to summarize results. The isolation of the tuberculous patients has reduced to a minimum the danger of infection of other patients and of emplovees. The patients themselves have suffered no injury or hardship, but have, on the contrary, been unmistakably benefited. This is shown, among other ways, by a decrease in the death-rate from pulmonary tuberculosis, both absolute and relative, and by a marked general increase in bodily weight, amount ing in the case of one patient to an actual doubling of weight — from eightv-three to one hundred and sixty-six pounds — in fourteen months of Camp residence. I prefer to advance these proofs, as they depend upon figf.res which are not capable of manipulation, rather than the usual percentage calculations of '"improvements,'' and especially ble. Others whose condition in the latter respect was similar have been returned, their insanity still continuing, from the tent to the ward, and after periods extending in individuals as long as two years, continue, as far as can be found upon most thorough investigation, immune from reappearance of the disease. In other such cases again, but these are fewer in number, confinement to the wards has resulted in return of phthisical manifestations ; but even in this most unfavorable class the benefits of the outdoor system have been demonstrated, for invariably improvement has again speedily followed upon their prompt return to the Camp. Mental improvement has as a general rule been the concomitant of physical, not only among the patients in the Tuberculosis Camp, but also in the others, and in the former class this has been somewhat of an anomaly. My experience, and I think that of others, has been that when phthisis and insanity co-exist they are apt to alternate as to the prominence of their several manifestations— the mental symptoms being more pronounced whilst the physical are in abeyance, and vice versa. Under the tenttreatment we have found a general disposition toward accord in the manifestations, improvement in both respects proceeding concurrently, and some of the discharges from the hospital which gave most satisfaction to us at the time, and most assurance for the patient's future, were of inmates of the Tuberculosis Camp. The mental improvement, even in cases where recovery was not to be looked for, has been a gratifying feature of the Camp experiment, and depending largely, as it has, upon the patient's satisfaction with his new surroundings, has served to dispel one of the doubts with which the experiment was undertaken. It was apprehended that not only might the patients themselves resent their transfer, but that similar objection might come from their relatives and friends, since innovations, even progressive ones, are apt to be frowned upon by those who constitute the majority in the clientele of a public hospital in a cosmopolitan city. Even at the outset, however, the protests, whether from patients or their friends, were surprisingly few, and latterly they have been more apt to arise, if at all, over the patient's return to the buildings when that became necessary. Through- out the winter months constant and anxious inquiries have been made, both by patients who had been in the non-tuberculosis camps and by their visitors, as to how early in the spring the former might expect to resume their camp life. The question of medication may in the present writing be dismissed with a very brief reference. It has been found unnecessary to extend it greatly, and it has been limited mainly to the treatment of symptoms. Stimulation — alcoholic and the like — has been found of but little demand or use, and the quantities consumed — always under individual medical prescription — have been insignificant. On the other hand the dietary has been made as liberal as the imposed restrictions of the State Hospital schedule have permitted, both in the way of regular diet and extras, and in the leading essentials — milk and eggs — private donations have supplemented the regular supply. But dependence, after all, has been mainly placed upon rigid isolation and disinfection, and upon the unlimited supply of fresh air. As an interesting incidental fact it may be mentioned that not only the patients, but also the nurses living in the Camp have enjoyed almost complete immunity from other pulmonarv diseases. Not a single case of pneumonia has developed in the Camp in its existence of over three years, though it caused 131 deaths in the hospital proper in that time. The "common colds" so frequent among their fellows living upon the wards, or in the Attendants' Home, have been unknown among the tent-dwellers. The popular idea that the consumptive is a doomed man unless he can at once abandon home and family and business and betake himself to some remote region would seem to be negatived by our \\''ards Island experience. So also with the strenuous claims for high altitude. The Ward's Island Camp is but a few feet above the tide-water level, its site is swept in winter by winds of high velocity, coming over the ice-bound waters of the rivers and the sound which > surround it, and it suffers as much as, or more than, any other part of the city of New York from the trying changes of temperature and humidity which are so characteristic of its climate. If, in spite of all these drawbacks, what has been done can be done, and that for insane patients, what may not be hoped from the extension of the same methods to the ordinarv^ consumptive of sound mind, anxious for recovery, and capable of giving intelligent assistance in the struggle? A. E. Macdonaed, Mendocino State Hospital for Insane, Talmage : Seven tents have just been erected tor the tuberculous patients. Three are for dormitories, accommodating fifteen patients, one is a sitting-room, one a kitchen, one a lavatory, and one is for attendants. Most of the food will be supplied from the main building, but a kitchen has been provided for the purpose of preparing the extra food that will be required. It is planned to keep patients in the tents throughout the winter. The Superintendent is E. W. King, M. D. Government Hospital for the Insane, Washington : A separate building is used for the accommodation of twenty of the consumptive men in this hospital. The rest of the forty-five or fifty tuberculous patients are isolated in single rooms or small wards whenever this is possible. The Superintendent is William A. White, M. D. State Insane Asylum, Jackson : Two one-story pavilions for the white male and white female consumptives of this institution are nearly completed. The building for women will accommodate thirty-two patients ; the one for men, forty. Both are isolated and have been constructed with special regard to thorough ventilation. The tuberculous patients will be kept entirely separate from the others ; they will have their own recreation grounds, will receive special treatment and diet, and will lead an out-of-door life as much of the time as possible. Springeield State Hospital eor the Insane, Sykesville: For three years tuberculous patients have been kept in tents for about eight months during the year. On account of the high rate of improvement in the patients under this regime it is planned soon to extend the outdoor treatment throughout the year. Separate buildings, accommodating about 40 patients, were set aside in 1897 for the consumptives of the institution. They are brick buildings two stories in height, located on elevated ground. Manhattan State Hospital, East, Ward's Island (a state institution for the insane) New York City: Tuberculous cases are isolated in tents. In the winter of 1903-04 there were over forty patients treated in this way. The system of tent treatment was inaugurated in June, 1901, and each year it has been extended, either in time or in the number of patients included, until at present all the active cases of tuberculosis in the institution are kept in tents throughout the year. HOSPITALS FOR THi: INSANE The colony is situated on sloping ground about 60 feet above sea level, and has a moderate amount of shade. The soil is dry and well drained, over a rock bottom. There are two tents, accommodating twenty beds each, 20 by 40 feet and 14 feet high, with the wall 6 feet high. A smaller square tent provides three beds for critical cases. Similar square tents serve as dining-rooms, while smaller ones are used for linen rooms, storerooms and bath rooms. County : During the summer of 1903 life m a tent colony was tried for about fifty tuberculous men and women. Each of the two sets of tents included a dormitory for twenty or twenty-five patients, a bathroom, a dining-room, and a small tent for storage. There was a telephone in each tent and running water. Here, as on Ward's Island, it was found that the patients liked their outdoor life and gained in every way. The experiment lasted from early summer until extremely cold weather, and was repeated and extended in the summer of 1904. It is hoped to extend and develop the system until all the tuberculous patients can be kept out of doors practically throughout the year. burg and binghamton : The State Commission in Lunacy is planning the erection, within the present year, of a large pavilion in connection with each of these hospitals, for the special treatment of insane persons suffering from tuberculosis. They are designed to accommodate 100 patients each, and are modelled after the plans awarded the first prize in the contest for plans for the King Edward Sanatorium in England. Columbus State Hospital for the Ixsaxe: In the spring of 1903 a tent camp was equipped for the care of twenty-four women affected with tuberculosis. The results were so satisfactory that the camp was kept open until Xovember 5, and in 1904 was increased to a capacity of eighty-four patients, Xot only were most of the patients benefited physically by the outdoor life, but many of them also improved mentally, and all were pleased with the new way of living. Two large tents, for sixteen patients each, are used for men, and there are several smaller ones, with a capacity of eight each, for women. Patients are classified in the camp according to the stage of the disease and according to their mental condition. Close observations are made on each patient and daily records are kept of his mental and physical condition, in connection with records of the climatic conditions. The camp is lighted by electricity and supplied with hot and cold water, and connected by telephone with the main office. ]\Ieals are served from the main kitchen in a dining tent. An interesting fact is that the expense of installing the six tents used during the first season and the cost of maintenance, with the exception of food, was only $1,400. At this institution two tents, each 20 by 40 feet, are used each year from May until December for tuberculous patients. The Superintendent is George F. Keene, ]M. D. A separate ward building, containing twenty-two beds, for the segregation of the tuberculous male patients, is in process of construction and near completion. It is possible and perhaps probable that the incoming legislature will appropriate money for the erection of a similar building for the segregation of female patients. Central State Hospital for the Insane, Petersburg: Tuberculous patients are segregated in two camps, one for the male and one for the female patients. These camps consist of tents of various sizes, for sleeping apartments, dining-rooms, bathrooms, and one for the acute sick. They are located on a lawn entirely apart from all other patients. The number of cases in the two camps averages between sixty and seventy. The camp for men was opened in May, the one for women in July, 1904. CULOSIS IN PENAL INSTITUTIONS Primarily the prevention of tuberculous disease in penal institutions begins with the early life history of the juvenile offender, which is not within the province of this article. Aside from this feature the prevention of tuberculous disease in penal institutions presupposes, ifirst, proper housing. Tuberculosis is essentially a house disease. It is bred, fostered and propagated in a larger degree through the housing environment than through any other one means. An inspection of the penal institutions of this country will show that the housing facilities of the majority are of a character decidedly favoring the development and spread of tuberculosis. The location, elevation, exposure to sunlight, of the buildings for housing and manufacturings purposes, and the sewage and drainage, of many institutions are defective when judged from the tuberculosis standpoint. The second great factor in the development and propagation of this disease in penal institutions is cellular confinement, in both the regulation and the punishment cells, especially the dark cells. In the damp, dark corners of the cells of most instilions, almost never visited by sunlight, the tuberculosis germ lurks and propagates itself through the medium of the cell inmates. Added to this is the ancient and common practice of using whitewash as a cleansing and disinfecting agent. As such, whitewash is a delusion. Observation and experiment show that whitewash really promotes the spread of tuberculous disease, or it may do so. The fine scales and floating particles that emanate from the dry whitewash when disturbed not only irritate the bronchial mucous membranes, but they are also carriers of infection to the point iritated. This has been demonstrated to my entire satisfaction by cell scraping. Certain experiments with lime burners also go to show that lime dust is favorable to the production of tuberculous disease. The bucket system, in use in most penal institutions, is another factor in the production of tuberculous infection, vitiating as it does the atmosphere of the cell and thus producing conditions favorable to germ life. Still another factor is the unsanitary construction and uncleanliness of workshops and factories connected with these institutions. Never can it be hoped to eradicate tuberculosis from the penal institutions until there are radical improvements in all these and other like features of the prison housing and grounds. The buildings connected with penal institutions should be especially constructed with a view to proper sanitation. The grounds should be well-drained, the sewage system complete, and the buildings so placed as to admit both the morning and afternoon sunlight. They should have high ceilings, large windows, and an adequate ventilating system. The cells should be large, well-lighted, and provided with water-closet and washbasin. These cells should be constructed of steel, and a washable paint used as an interior finish. The cell halls should be kept scrupulously clean, and at stated periods washed with antiseptic solutions. All cells vacated should be disinfected, and no whitewash used about the prison interior. Next in importance to the housing is the feeding, clothing, and body hygiene of the prison population in insuring a high resisting power in the individual. While the food must necessarily be plain and simple in character, it should nevertheless be varied to suit conditions and seasons. It should be nutritious, and a careful balance maintained betAveen the proteid and starchy foods, with a generous admixture of fresh vegetables. Especial attention should be paid to the clothing and bathing of penal populations. Spray baths should be given at frequent intervals ; the clothing should be adapted to the seasons, kept clean and frequently disinfected by dry heat : and personal cleanliness should be insisted upon. All men confined in penal institutions should be permitted to exercise at some period of the day in the open air. There are many other features in detail which might be enumerated, and which are important in the solving of the problem of the prevention of tuberculosis in penal institutions, but those indicated are the chief factors, and if strictly carried out would accomplish much toward preventing the disease. The first step in the intelligent and effective treatment of the tuberculous prisoner is the introduction into all the penal institutions of systematic methods of examination, which will make not only possible, but certain as may be, the early diagnosis of the disease. .g^ Under the methods of the past, and, I may say, mostly of the present, the tuberculous may be found scattered through every department of penal institutions unrecognized, none but the most advanced and self-evident cases receiving special treatment and isolation. Thus the majority of incipient cases go slumbering on, until the disease has so far advanced that recovery is made hopeless in many cases and the infection is consequently conveyed to many other persons. To remedy this defect a law should be enacted making it m.andatory upon the physicians of all jails and penal institutions to examine every man upon reception, with a view to detecting every case of tuberculosis, no matter in what stage, and to fill out a proper certificate, showing the condition of each person examined, a copy of which certificate should, in jail cases, be submitted to the court of trial, in order to hasten the trial of the tuberculous person, and should, in case of commitment to penal institutions, accompany the regular commitment papers. As soon as an adequate system of identification for the tuberculous criminal has been put into working order, the whole problem will become greatly simplified. When once the prisoner is found to be tuberculous, he should at once be isolated from the general population and subjected to observation. If, after observation, it is found that his disease is not in an active stage, that his general condition is good, that he is not coughing or expectorating, and that bacilli are not present in his sputa, he can safely be assigned to some form of light work that will admit of his receiving a degree of air and sunlight, and not expose him to a dusty atmosphere. His case should, however, always be under close scrutiny, with a view to anticipating any renewed activity of the disease. If the disease is at all active the patient should be admitted to regular hospital treatment. My own experience leads me to believe that this is best carried out in large open wards with high ceilings, admitting an abundance of sunlight and fresh air. After admission to the wards the treatment of the tuberculous prisoner does not differ materially from that of the tuberculous citizen, except that there are certain conditions which arise depending upon, and peculiar to, the prison environment. The subjective effects of this environment are the element of mental depression and consequent unstableness of the nervous system, caused by the shock of arrest, trial and imprisonment, and the enervating effects of confinement under penalty. These special conditions must be met by appropriate treatment, and this, the nerve feature of the tuberculous prisoner, requires very much more attention than in the case of the ordinary citizen. The objective conditions are those which necessarily arise from the effects of prison discipline upon the prisoner. He must conform to certain fixed rules and regulations, and therefore a full degree of freedom of individual action cannot be permitted him. Neither can he receive the amount of outdoor ,air and exercise that his case may require, as only at certain hours of the day can he be permitted outside Lhe prison walls. Fresh air and sunlight are the essential factors to the successful treatment of tuberculosis. These cannot be furnished the prisoner in the ordinary cell halls of a prison. However, it is my belief, derived from my own experience, that a satisfactory system can be devised for providing these requisites to the tuberculous prisoner by separate hospital buildings, provided with large open wards, so arranged as to admit plenty of air and sunlight, and with sufficient outdoor grounds for open-air treatment. The advantages of the open-ward treatment lie in the greater facility with which the attendants and officers may superintend their charges, and in a certain amount of social intercourse between inmates which can be permitted them under this system. As an illustration of the advantages to be derived from this method it may be well here to describe the new tuberculosis ward now in use in Clinton Prison, in connection with the regular prison hospital. While not carrying out the above idea in full, it is a great step in the right direction, and has decidedly proved its efficiency. This ward is an addition to the regular prison hospital, but separated entirely from the other wards by the main central court of the prison hall entrance. It is situated on the top floor of the administration building, and is open to the air on the eastern and western sides of the building, thus receiving a plentiful supply of light and air. and is also protected on the northern side by the main buildings. It accommodates forty-three patients, and is provided with suitable modern sanitary arrangements. In connection with this ward is an eleven-bed ward for the treatment of the extremely advanced cases, making a total of fiftyfour beds. There is also an outdoor sunning and exercise court, which is provided with benches, elevated cuspidors containing TUBERCULOSIS IN PRISONS antiseptic solutions, crematory for the sputa and the spit cups with which each inmate is provided, running spring water, and water-closet, as well as sufficient shade, afforded by a few trees, for the extremely hot summer days. Treatment of the patients here is practically divided into three phases : physical, medicinal and dietetic. The first consists principally of simple calisthenics and outdoor exercise in the court above described, morning and afternoon, which is required of each patient whenever the weather and his condition permit. The medicinal treatment, while subordinated to the physical and dietetic, is nevertheless an essential feature, and such medicaments as the iodins, creosote, guaiacol, ichthyol, formalin, cod liver oil, stomachics and tonics are used, according to the requirements of the different cases. The ultra-violet X-ray has also been used to a considerable extent with beneficial results. The diet is prescribed daily by the physician, and is furnished on his order from the hospital kitchen. It is aimed to make this diet as nutritious as is consistent with available means, and it includes principally cereals, vegetables, milk, meat, eggs and fruits. It is also intended to instruct each patient thoroughly, on admission, as to the necessary sanitary rules peculiar to his disease, as regards the care of his person, clothing and sputa. He is required to conduct himself in an orderly manner and keep his person clean and neat. He is permitted, within certain limits, to mingle and converse with his fellow patients, and to play checkers and dominoes with his neighbors, and is supplied with plenty of good reading. This ward is in charge of a hospital attendant — a trained nurse — who is always in attendance during the day. While it has been in use less than two years, the results shown have surpassed all anticipations. Many patients are admitted in an emaciated, anaemic, and exhausted condition, apparently to live but a short time, but a few days under this systematic routine and treatment make a manifest improvement in them. If they carry temperature, it gradually subsides, their natural color returns, and many of them gain materially ni weight. A goodly number are apparently cured, many cases are arrested, few die; and all the deaths have occurred in cases which were received in the prison in the last stage of the disease, and were utterly hopeless on reception. The results obtained in this prison by the conditions of a prison. A separate hospital building of sufficient capacity to accommodate all the tuberculous inmates of the penal institutions of the state, provided with properly fitted wards, modern sanitary appliances, and outdoor and indoor exercise courts, isolated completely from the prison population proper, presents without question the solution of the problem of the treatment and prevention of this disease in the penal institutions of the state. When a patient has arrived at an arrested stage of the disease, he can advantageously be employed at some light work, which, I believe, is best represented by light gardening. In this way a sufficient quantity of vegetables and relishes can be raised to supply the needs of the patients, they receive the benefit of the exercise, their minds are diverted into a healthy channel, which is a very important factor, and the produce supplied by such labor undoubtedly pays for the extra expense incurred in the guarding while at work. The whole solution appears to me to lie in the institution of a practical system such as outlined above, which, briefly stated, means the enactment of a law providing for the early diagnosis of the disease, the construction of a modern, isolated, tuberculosis hospital building of sufficient capacity, and the compulsory transfer to it of all established cases of tuberculosis. INDIANA In the State; Re;formatory, at Indianapolis, consumptives are segregated in special wards and sections of cells, and are kept under a special regimen as to work and diet. The physician in charge is H. C. Sharp, M. D. culous convicts. Since the summer of 1894 sputum examinations have been made in all suspected cases, and when tubercle bacilli are found the man is transferred to a section of cells reserved for such cases. Special care is taken of these cells ; they are inspected and cleaned daily. Every precaution is taken against the spread of infection. The consumptives have their meals in their cells, and they are given a better and more varied diet than the other convicts. They are given out-of-door work apart from their fellows, and when too ill to work they are kept out of doors during working hours, both summer and winter. CijNTON Prison, one of the three state prisons, is located at Dannemora, in the Adirondacks. Since 1895 there has been a systematic attempt to transfer here from Auburn, Sing Sing, special treatment. A small isolation ward for ii cases was the only hospital provision until 1902. In July of that year a special ward accommodating 43 patients was constructed. In connection with the ward is an exercise court where the patients are kept in the open air as much of the time as possible. A new building, with a ward of 100 bed capacity, is now under construction. In addition to the 54 who can be cared for in the existing ward, nearly 200 other consumptives are treated in cells used exclusively for this purpose. Dannemora lies on one of the eastern spurs of the Adirondack ]\Iountains, at an altitude of 1,500 feet. It is protected by mountains on the north and west, but open to the south and east, and thus is weU exposed to sunUght. It is partly surrounded by dense tracts of uninhabited forest, has a light annual rainfall, and the air is relatively dr\- and sterile. State Penitesttiamy, Columbia: A separate building for the tuberculous prisoners is projected. It will be located on the penitentiary grounds, and will accommodate about fift\-. It is hoped that it will be ready for use in August, 1905. The Farm was established in 1899, for the isolation and care of tuberculous prisoners in the Texas penitentiaries. It is located on a high, well-drained spot, two miles northwest of Hnntsville. There are no timbered lands near the buildings and the supply of air and sunshine is thus unobstructed. Sergeants and camp physicians in charge of the convict farms all over the state are instructed to transfer here all men suffering with tuberculosis as soon as the disease is recognized. Some, also, are received direct from the jails. During- the first three years the total number treated was i8o, of whom 67 were Negroes, 65 white, and 48 Mexicans. All the men who are able are required to do some work, consisting of light farming, gardening, poultry and stock raising. The garden products supply Wynne Farm and the Huntsville Prison and leave a surplus for the market. It is believed that the Farm will soon be self-sustaining, aside from the expense of guarding the men. It has seemed difficult for the medical or lay sanitary authorities to understand that with the new knowledge afforded by the observations of Koch and others an entirely different sanitary problem was presented for their consideration, and that for its solution new methods must be adopted. Very gradually comprehension of this simple and apparently quite self-evident fact lias forced itself upon them. It may be said now to be an almost universally accepted fact that some kind of action or supervision is justifiable and necessary, and the only difference of opinion is as to the extent of the measures which should be adopted and as to the manner of their enforcement. ffcation and registration of all cases is essential. The fundamental importance of this measure is so evident that its consideration seems hardly necessary. It must, of course, appear at once that unless there is a system of compulsory notification and registration the enforcement of any uniform measures for prevention is impossible. Practical experience with this procedure has made it perfectly clear that the objections which have been urged against it are without force or foundation. The notification of a case of tuberculosis does not require any action on the part of the authorities, if it seems reasonable to assume that such action is unnecessary. The very fact that tuIberculosis is notified by the attending physician as a communicah\e disease has the greatest educational value, and justifies the assumption, in those instances in which the case is under the supervision of a private physician, that reasonable and necessary precautions for the protection of others wall be taken. If, however, the consumptive has the disease in an infectious stage and is without a home, or is living in a lodging-house, or in a poorly furnished room, or in a family in a tenement house, or is receiving medical advice through some public institution, then all ob- MUNIC:iPAI, CONTROIv jection to the interference or the supervision of the authorities is removed, and in the interests of the pubHc such interference and supervision become necessary. It should be strongly emphasized that the mere fact of notification and registration has in itself a very powerful educational influence. 2. Fre;^ BactdrioIvOGicaIv Examination oe Sputum. — To facilitate the early and definite diagnosis of all cases of pulmonary tuberculosis, the sanitary authorities should afford facilities for the free bacteriological examination of the sputum in all instances of suspected disease. In a large proportion of the cases of early disease the physical signs and the symptoms are not sufficiently definite to permit a positive diagnosis by the general practitioner. An expert may easily arrive at a positive conclusion, but the general practitioner remains in serious doubt. In the absence of a positive result from an examination of the sputum, the attending physician awaits the appearance of more definite signs, and thus too often loses most valuable time, for these more definite signs mean further extension of the disease in the lungs. In some institutions, and by many physicians, the positive position is assumed that no case is to be regarded as tuberculosis of the lungs unless tubercle bacilli are found in the sputum. It is hardly necessary to point out how erroneous and dangerous is this opinion. It is the general opinion now that such free bacteriological examinations should be made by the authorities, and that every convenience and facility for them should be afforded. It is a curious fact, in this connection, that large numbers of physicians in private practice who are unwilling or reluctant directly to report cases of tuberculosis, without hesitation send specimens of sputum for examination, with all the facts in relation to the patient which are necessary for registration. 3. Educationai, Measures. — It is difficult to overestimate the importance of the duties of the sanitary authorities in the education of the medical profession and of the people on the subject of tuberculosis. Circulars in as many languages as necessary, designed to reach different classes of the community and covering different phases of the subject, should be widely distributed, and the public press should be utilized to the very largest extent in the diffusion of information. The circulars as issued should be given to the press for general publication. immediate visitation by a physician or trained nurse of every case of tuberculosis not under the care of a private physician or m a pubhc institution, as soon as it is reported. At these visits verbal instructions should be given, and printed circulars left for the information of the patient and the family. At the same time data should be gathered as to the history of the sick person and of the family, its social condition and financial income, the number of persons in the family and their wages ; the number of cases of tuberculosis which have occurred, the probable source of infection in the individual ; the sanitary condition of the premises, the amount of air space for each person, the character of the light and ventilation, the precautions being observed and the possible need of any further interference on the part of the authorities. In the course of these visits it becomes evident in many instances that a patient should be removed to a hospital or sent to a sanatorium outside of the city. In such instances, if possible, the patient should be induced by persuasion to avail himself of such institutional care as seems desirable or available. If the patient persistently refuses institutional care forcible removal must be resorted to in those instances in which the unsanitary conditions existing render it necessary. 5. Disinfection. — The disinfection or renovation of rooms or apartments which have been vacated by consumptives either by death or removal is another essential part of the system. Trained medical inspectors should be sent whenever it comes to the knowledge of the authorities that premises have been vacated by death or removal, and proper measures adopted to enforce disinfection of the premises by means of formaldehyde gas, or thorough renovation. In those instances in which the premises are dirty and filthy, and the walls and ceilings are in bad condition, renovation, to be performed by the owners, should be required. If necessary for this purpose, the apartments may be vacated, or, if already vacant, the occupation by others must be prohibited until such renovation has been completed. Carpets, rugs, clothing, pillows and mattresses, and anv bedding or other textile fabrics, which cannot be properly disinfected by formaldehyde, should be removed by the authorities, and subjected to steam disinfection. Disinfection should be carried out by the health authorities without cost to the occupants or owners, but the cost of renovation, when required, should be borne by the owner of the premises. frequent changes of residence of some families containing coniiumptives ; and as the famihes become constantly poorer on account of the financial loss and expense entailed by the illness, they move continually to a poorer and poorer class of tenements. It is often impossible to trace them, or to obtain information of their change of residence, so that proper disinfection of the apartments may be ensured. The owners of the property may, of course, be required to furnish information of the removal, but there is danger lest this course may eventually entail some hardship on the poor consumptive in rendering it more difficult for him to find lodgings. This is the most troublesome problem to solve which has been found in this connection in New York. It may be that eventually notification by the owner of the removal of a consumptive will be necessary, as the only solution of this difficulty. 6. Re;pEate;d Visits. — Provision should be made for making repeated visits to cases in tenement houses, when for any reason it has been undesirable or impossible to remove the patient to an institution. These revisits may usually be best made by trained nurses. In this way information may be gathered as to changes of residence, as to the efficiency of the precautions adopted by the consumptive, as to the changes in his physical condition or the financial resources of the family, and as to the necessity of any alteration required in the sanitar}^ treatment of the case. 7. DiLT. — Suitable food, especially milk and eggs, should be provided by the sanitar}^ authorities, or by other authorities having supervision of such afifairs, in those instances in which the families are in such destitute circumstances that proper or sufficient food cannot be obtained by them, and when the patient for any reason cannot be removed to an institution. 8. Institutions. — The sanitary authorities should provide, or see that there are provided, and should supervise, three classes of institutions for consumptives : Free Dispensaries. — In these free dispensaries medical treatment for ambulatory cases should be provided. These cases should be constantly under the supervision of the district physicians and nurses attached to the dispensary. When necessary, not only medicines, but food, should be furnished free by the dispensary to the consumptive poor. The dispensaries should also act as clearing houses for consumptives, and should serve as places to which all institutional cases on their discharge from ■institutions and all poor cases receiving the care -or assistance of charitable organizations, should be referred for medical care. From this dispensary suitable cases should be referred to either a sanatorium or a hospital, as seems necessary. Hospitals for the Care of Advanced Cases. — It is not necessary that all the hospitals for the care of advanced cases should be directly under the control of the sanitary authorities, although they should exercise a general supervision over these institutions. It is necessary, however, at least in a very large city, that the authorities should have control of at least one institution with adequate facilities for the care of certain varieties of advanced cases of the disease, which it may be necessary to remove forcibly to the institution and retain there. These cases are of several types : first, those who are discharged from other institutions, because they are, from the institutional standpoint, exceedingly undesirable patients, or because they have violated the regulations of the institution ; second, cases living in lodging houses and inmates of public institutions not having- facilities for their care, who are unwilling to enter any of the hospitals which are available, but who must be provided for in some way ; third, cases which are almost necessarily sources of danger to the other members of their family, by reason of extraordinarily unfavorable sanitary conditions, great poverty, or overcrowding, but are vmwilling to enter an institution; fourth, numerous cases which have already been under the care of an institution, and which become for some reason dissatisfied with their care and are determined to return to their homes, although the familv is unwilling or unable to provide properly for them. All such cases — homeless, friendless, dependent, dissipated, and vicious consumptives — are the ones likely to be most dangerous to the community. They must be provided for by the sanitary authorities at any cost, and if necessary the health authorities must intervene to remove such patients by force to suitable institutions and there detain them.' Sanatoriinns. — The sanitary authorities should provide, or have available, proper sanatoriums in favorably situated country districts for the care of early and incipient cases. No further comments seem necessary on this phase of the subject. tions as to the care of consumptives. The admission and treatment of such patients in the general wards of general hospitals should be prohibited, and all public institutions caring for such patients should be required to provide separate rooms or wards. These regulations should apply not only to general hospitals, but also to the hospitals for the insane, to penal institutions, homes and asylums. Suitable regulations should be formulated in regard to cases occurring among the teachers or pupils in the public schools, and emplo37ees in factories, workshops and mercantile establishments, and in regard to occupations of a nature likely to disseminate the disease. lo. Ordinances against Expectoration. — The sanitary authorities should enact and enforce regulations prohibiting spitting on the floors of all kinds of public conveyances, such as street cars, steam railroad cars, and ferry-boats, and on the floors of public buildings and places of public assembly, such as ferry-houses and depots, and in the halls of tenement houses, in theatres, in factories and in workshops. Spitting on the sidewalks should also be prohibited. When we have educated the mass of people up to this view, so that this habit of spitting will not be tolerated, the chief factor in the solution of the problem of the prevention of tuberculosis will, in my opinion, have been found. A number of measures of minor importance in the surveillance of the tubercular diseases have been in operation in New York City. Among these ma}^ be mentioned the semi-annual census of the cases of pulmonary tuberculosis under treatment in public institutions in the city. It has also been the custom during the last two or three years to communicate with the attending physician in cases of tuberculosis which have been reported through the sputum examination or directly and to inquire whether the patient is still under treatment, and if so^ whether improvement has taken place or not, and whether the physician has any objection to a visit's being made to the patient if he is not at that time under his observation. If the physician replies that the patient has passed from his observation, and he has no objection to an investigation by the department, an effort is made to locate the patient and determine what the condition is. Sanitary cuspidors are supplied by the department through trained nurses for the use of very poor patients in the tenementhouse districts, and large numbers of these cuspidors have also been supplied to various charitable societies, which have super- vision of, or are extending help to, cases of consumption in their homes. Large numbers of circulars of information have also been supplied to these societies for distribution, and similar circulars in various languages have been furnished to various labor unions for distribution among their members. The inspectors of the Tenement House Department and visitors of the Charity Organization Society and other private societies, report to the Department of Health any cases of apparent tuberculosis which they may find, and these are investigated by the Department of Health. Attempts have been made to secure the condemnation by the city of several areas in the tenement-house districts in which tuberculosis has been particularly prevalent. One minor measure which has been found of much service in New York has been the house-to-house inspection in tenementhouse districts by women physicians in the search for unreported cases of tuberculosis. Quite a large number of such cases have been found in this way, especially among the foreign population. It is also of the greatest importance, in this connection, that the trained nurses and medical inspectors should know the language of the people whom they are visiting. Great care has been taken, as far as it was possible under the civil-service regulations, to obtain trained nurses and physicians who speak foreign languages. We have now, engaged in this work, nurses who speak French, German, Yiddish, Russian, Italian, Chinese, Slovak and Polish. scheme for the efficient administrative control of tuberculosis. In its main and most important features such a plan has been in force in New York City for a number of years. The feasibility and the practicability have been conclusively demonstrated by experience in the second largest city in the world. In only a few of the less important details is the general plan as now followed in New York wanting. Very great opposition met the proposition of the Department of Health to undertake this work in the beginning, and many difficulties were encountered in the early years owing to this opposition. But experience has shown that the obstacles are largely imaginary ; that the harmful results which were predicted as certain to follow have failed to materialize. Practically no serious difficulties are encountered in carrving on the work. The difficulties are really less serious than those encoun- tered in connection with the contagious diseases. There has been hearty approval by the majority of the medical profession, and acquiescence by the remainder. In answer to the question, What may reasonably be expected from the enforcement of such measures? we find again an answer in the experience of New York. There has been a more rapid fall in the tuberculosis death rate in New York City than in any great city in the world, and this notwithstanding the fact that the conditions in many respects are much more unfavorable, because of the very dense population in the great tenement-house districts of the city and the large element of foreign-born population. Various investigations that have been carried on by the Department of Health seem to substantiate the conclusion that the decrease in the deaths from tuberculosis is a real one and not in any m.aterial respect merely apparent. It is not at all intended to indicate that the whole of the reduction in the death rate from tuberculosis in New York City has been the result of the measures directed especially against this disease, for many other factors have undoubtedly contributed to it, but I do believe that the very great and rapid fall in the tuberculosis death rate is the direct result of the application of these measures ; and I fully believe that the next fifteen years will see a reduction quite equal to that which has already taken place. If we accept at all the necessary deductions of our scientific convictions in relation to tuberculosis there can be no escape from the conclusion that tuberculosis is, of all the important infectious diseases with which we have to deal, certainly the most preventable. The experience of New York City may be regarded as furnishing proof of the truth of this conclusion CIPAL CITIES OF THE UNITED STATES To ascertain what was being done in the wa}^ of administrative control of tuberculosis in the principal cities of the country a letter of inquiry was addressed to the president of the board of health in each of the seventy-eight cities of more than 50,000 inhabitants. After a suitable interval a second inquiry was sent to all who had not responded to the first. From ten of the cities no reply whatever was elicited, nor were the letters of inquiry returned unclaimed. These ten were Pittsburgh, Allegheny, Harrisburgh and Scranton, in Pennsylvania ; Charleston, South Carolina ; Des ]\Ioines, Iowa ; Detroit, Michigan ; Kansas City, Kansas; Portland, Maine; and St. Joseph, Missouri. The infarmation that was received from the other sixty-eight may not represent quite all that is now^ being done by the city authorities, as new measures may, in a few cases, have been instituted in the few months since the inquiry was made. In fifty-nine of the sixty-eight cities from which replies were received tuberculosis is now "ofiQciallv recognized as a communicable disease," but it is probably true that "that is all that is done in the matter," in more of the fifty-nine than the one which plaintively admitted that such was the state of afifairs. On the other hand, four of the nine cities which deny that they recognize the communicability of tuberculosis, betray, either in publications of the department or in answer to other questions, that they efir'ectively subscribe to the doctrine. In fifty-nine of the sixty-eight cities also, there are more or less comprehensive ordinances against expectoration in public places, and in two or three others an ordinance is under consideration. The prohibition contained in some of these ordinances applies only to street Cars, the enforcement being left entirely to the street-car companies ; in others — a few — practicallv every public spot is interdicted to the promiscuous spitter. offenders are subject to arrest, and as severe a penalty mav be imposed as a fine of $500 or imprisonment for one year. In four of the cities, it is claimed, the ordinance is enforced "strictly." "successfullv," or "well" ; in four cities, "fairly well" ; in three, "never" or "not at all" ; while in a large proportion of the rest the enforcement is admittedly "indifferent," "not very effective," "not what it should be," or "not rigid enough," and penalties are imposed only "at times" or "seldom." It is sufficiently evident from every-day experience, without the confirmation of these comments, that the mere existence of ordinances against expectoration does not solve the problem. It is something, however, that in so many cities the public has arrived at the point of realizing that the ordinances are desirable, and doubtless the placards which are displayed have some psychological effect, even in places where no prosecutions are made. The health officer of one city remarked that "although this regulation is not enforced, still it has done some good." These ordinances are all of recent date. Among the fiftytwo cities which furnished information on this point of date, New York was the pioneer, early in 1896, closely followed, in the same year, by Boston and Los Angeles. In 1897 eleven other cities passed similar ordinances; in 1898, six; in 1899, ten; in each of the next two years, eight; but since 1901 there have been only six added to the list, unless some of the seven which failed to give the date belong here. The reporting, to the board of health, of all cases of tuberculosis, while still living, is requested or required in thirty-nine cities, exactly half of the total number of seventy-eight, and it is contemplated in at least three more. Whether this notification is "requested" or "required" is of little practical significance, since in no city has recourse ever been had to prosecution for failure to report, even if such failure is a violation of a "requirement" of the sanitary code. In New York City a system of persistently reminding institutions and physicians of their duties in this respect and of calling them to task for every delinquency that comes to the knowledge of the health department, has resulted in a fairly complete registration. Physicians have repeatedly been summoned to appear before the board of health to explain their failure to report cases. When they have failed to appear their attendance has been compelled by the issuance of a subpoena. Dr. Biggs estimates that the department has a record of 90 per cent of the consumptives of the boroughs of Manhattan and Bronx before their death, though in many instances, of course, it is only a short time before death. In a few other cities some such devices for securing the co-operation of physicians have been tried, but in none with sufficient persistence to bring about satisfactory results. Many of the health ADMINISTKATIVIi MKASUkES officers of the cities in which reports are required commented that the regulation is "not often comphed with" or "not generally obeyed," or volunteered the information that "very few reports are received." In no American city, so far as is known to the writer, has the English method of securing registration been adopted, by offering a small fee, usually two or three shillings, for each living case reported by a physician. If neither inducements nor punishments are resorted to, in order to secure compliance with a requirement to report, the only hope seems to lie with the New York method of patient persuasion and education, reenforced by the threat of legal procedure. The development of this necessary part of a system of administrative control is, as would be expected, even later and less far advanced than is the prohibition of spitting. Most of the progress in this direction has been made in the last five years. Disinfection of apartments in which consumptives have lived is recognized to be desirable in sixty-one of the sixty-eight cities from which replies were received. In two, however, it is "not done, on account of lack of appropriations" ; in three, "not unless requested" ; in twenty-seven it is done only "on request" ; in three others, "sometimes" or "occasionally" ; in two it is "recommended" ; and in regard to fourteen the extent to which it is done is not specified. In the other ten cities, it is claimed, disinfection is "required" after the death or removal of a consumptive. The favorite method of disinfection is by formaldehyde ; but in eight cases the scrubbing of floors and woodwork is added, and the disinfection of bedding and clothing by steam, Something in the way of educational work is attempted by the health department in twenty-nine of these cities. The usual method is to distribute, more or less widely, circulars of information in regard to the nature of consumption, how to avoid contracting it or giving it to others, and how the consumptive should live. In a very few instances use is made of the daily press, and public lectures are given. New York seems to be the only city, so far, in which nurses are employed by the department for the express purpose of visiting poor consumptives in their homes. In Rochester one has been asked for ; in Peoria one nurse, employed by the board of health, is sent to tuberculosis cases as well as to others ; in Cleveland, Washington, and Syracuse, by co-operation with private organizations, nurses are available for the needs of the department. In at least fifteen of the cities sputum is examined for physicians free of charge. The milk and meat supply is under more or less rigid control, either by city authorities or the state board of health, in sixty-two of the cities. In only a few cases is there careful inspection of the cattle, particularly in dairies, for tuberculosis. Any supervision, however, which has the effect of raising the standard of milk or meat supplied to the market, is an indirect measure for lessening tuberculosis. Several miscellaneous measures that have been adopted in different places deserve mention. A few cities supply sputum cups free of charge to needy consumptives. In Bridgeport, Connecticut, tuberculous children and pupils are excluded from the public schools. Indiana has recently passed a state law to the same effect. This seems, on the whole, neither necessary nor desirable. Cincinnati has, a few months since, put in force a well-planned system for the control of tuberculosis which has at least one distinctive feature. A physician who is specially qualified to do the work is employed to hold office hours at the department, for the purpose of making physical examination of suspected cases, on any physician's request. By this means it is hoped that many cases will be caught in the very early stages, before the sputum contains bacilli, or even before there is any expectoration. The more important measures which are peculiar to New York, among American cities, are, in addition to the provision for visits in the home, by nurses and physicians, the establishment and maintenance of a free municipal clinic especiallv for the treatment of tuberculosis and the exercise of the right of forcible removal. In view of the fact that we have for twenty-two years had in our possession all the knowledge essential to the intelligent sanitary surveillance of this disease, it seems incredible that so little has been done. The situation is a reproach to our intelligence and our public spirit, a reproach which will only be removed when every city in the land will have put into force, in its main features and wath whatever modifications are necessary for local conditions, the system of administrative control outlined by Dr. Biggs in the preceding pages. It is encouraging that thirty of the seventy-eight cities reported that plans were under consideration for the introduction of essential measures or for the further development of a system alreadv existing. There is no city in the United States in which a society for the prevention of tuberculosis would be useless or out of place. In no two, probably, would the activities of such a society be just alike, but in every one there exists the need for organized effort in reducing to a minimum the distress and loss of life caused by this preventable disease. The need for such effort is more conspicuous in the large cities, but the chance for satisfactorv results is greater in the town of a few thousand inhabitants. In the small town it should be possible to give proper care to every consumptive, to control every center of infection, to inform the public mind thoroughly, and to keep up with the needs of the population as it increases. These needs would be chiefly in the way of education, inasmuch as the original provision for the sick would, if the society worked eft'ectively, continue to be adequate and ultimately become minecessary. In a large city, on the other hand, the great numbers of sick requiring hospital and sanatorium care, the far greater numbers of persons to be instructed, and the greater difficultv in securing for all wholesome conditions of living, make the task seem less hopeful at the same time that they emphasize the importance of undertaking it. Fortunately, in a large citv many agencies will be found already working indirectly for the solution of the tuberculosis problem, and ready to undertake various parts of the task. But however efficient the health department, however plentiful the hospitals, there will always remain the Avork of education. ■ In regard to the composition of such an association the same general rule will apply everywhere. x\ membership that is representative, not only of the medical profession, but of other interests and activities, and especially of existing agencies concerned with the public health and practical philanthropy is an initial advantage in enlisting the co-operation of all the forces in the community and the interest of all classes, and is a constant safeguard against partisan views. SOCIETIES AND COMMITTEES Whether the association shall be independent or under the auspices of some existing organization is a question to be determined by local conditions. Both methods have been tried with satisfactory results. In New York, for instance, the association formed for this specific purpose is a committee of the Charity Organization Society, in Chicago it is affiliated with the Visiting Nurse Association ; in Saint Louis, it is a committee of the Civic Improvement League; while on the other hand the Boston and Scranton societies are examples of independent organizations. If the opportunity presents itself of affiliation with an organization of generally recognized importance in social work, it may be desirable for the new association to enter public life sO' sponsored, assuming that there are no conditions which might hamper its development in the future. On the other hand, the purpose of the new enterprise should be sufficient to commend itself to the public, provided that the personnel is guarantee that the work, as undertaken, will be worth while. The work which should be undertaken is also determined largely by local conditions. The general features of a comprehensive campaign being agreed upon, it is the part of the society or committee for the prevention of tuberculosis to initiate those parts of the task which have not been undertaken by any existing agency. A thorough survey of the situation should be preliminary to any plan of action. Care should then be had not to duplicate any work already being well done by the department of health or by a private society, though all possible assistance and encouragement should be given to such work. In developing the campaign it will often be found possible to induce older organizations to undertake such parts of it as are especially appropriate to them. Certain essential measures, such as the control of indiscriminate expectoration, the registration of living cases, disinfection, and free bacteriological examination of sputum, are more properly governmental functions and can best be administered by an efficient board of health. In a community which has a department of health no efforts should be spared to secure the expansion of its activities until it has developed the system of control described in this volume. In a community without an efficient department of health the society will find itself forced to try to supply the lack, preferably by securing the efficient department. diet, be of pressing importance for some time to come in every city. Xot until there is sufficient accommodation for every consumptive who cannot receive proper treatment at home can it be disregarded. There is room here for state, municipal and private enterprise, and little danger that the provision by all of them combined will exceed the demand. Although sanatorium treatment is preferable for most patients, even those in the earliest stages of the disease, nevertheless the special dispensary is now, and will for some time continue to be, a most important element in the provision for the tuberculous poor. For ambulant cases who are obliged to go on working, or for whom there is no room in a sanatorium, the special dispensary, with its visiting nurses, is at least the best makeshift yet devised for sanatorium treatment, and on the educational side it has large possibilities. Charitable assistance is required sooner or later by many families in which a case of tuberculosis occurs. It is not always necessary, perhaps it is not generally desirable, that the society for the prevention of tuberculosis should attempt to supply material relief; but it should at least establish relations with existing relief agencies and supplement their efforts in any way that is required, and it should keep constantly in mind and before the public the fact that the care of consumptives in their homes is a most important part of any scheme for the eradication of this disease. There is practically no limit to the amount of educational work to be done by one of the societies under discussion. By lectures to all classes of society, by distribution of literature, by house-to-house visits, by newspaper articles, by co-operation with the public-school teachers and trade unions, and in many other ways, the work of informing the public in regard to the nature of tuberculosis and the way to avoid it and to prevent its spread can be carried on. Xor is this work completed so long as any members of the community remain uninformed. The care of the tuberculous inmates of any insane hospitals or penal or charitable institutions within the territorial bounds set by the society should be a matter of interest to the society, and all possible eft'orts should be made to bring about the introduction of proper treatment in such institutions. In addition to all the direct methods of attacking tuberculosis there are many indirect methods which are no less important and which, in fact, are essential to a successful crusade against this disease. It is quite within the province of a society for the prevention of tuberculosis to initiate a movement for improved housing conditions or for better sanitary conditions in factories, workshops, stores, and schools, or for playgrounds in the crowded districts of the city. In a community in which there is no other active and aggressive body to do such work it even becomes a duty. In any case every movement which has for its object the improvement of living or working conditions should be heartily supported. After preliminary meetings in Baltimore and Philadelphia the constitution and by-laws of the national association were finally adopted on Monday, June 6, at Atlantic City, and officers were chosen. Dr. Edward L. Trudeau, of Saranac Take, N. Y., is the first president; Dr. William Osier, of Baltimore, and Dr. Hermann M. Biggs, of New York, are vice-presidents ; Dr. George M. Sternberg, of Washington, D. C, late Surgeon-General, is treasurer ; and the secretary is Dr. Henry Barton Jacobs, of Baltimore. The board of directors, including the officers above named, consists of Drs. Norman Bridge, of California; S. E. Solly, of Colorado ; John P. C. Foster, of Connecticut ; George M. Sternberg, of Washington, D. C. ; Arnold C. Klebs and Robert H. Babcock, of Illinois ; John N. Hurty, of Indiana ; William H. Welch, William Osier, Henry Barton Jacobs, and John S. Fulton, of Maryland ; Henry M. Bracken, of Minnesota ; William Porter, of Missouri ; Edward O. Otis and Vincent Y. Bowditch, of Massachusetts ; Victor C. Vaughan, of Michigan; Mr. Frederick L. Hoffman, of New Jersey; Drs. Hermann M. Biggs, S. A. Knopf, and Edward L. Trudeau and Mr. Edward T. Devine, of New York ; Drs. Charles L. Minor, of North Carolina ; Charles O. Probst, of Ohio; Lawrence F. Flick, Mazyck P. Ravenel, Howard S. Anders and Leonard Pearson, of Pennsylvania; Matthew M. Smith, of Texas; Major George E. Bushnell, of the United States Army Hospital, Fort Bayard ; and Surgeon-General Walter Wyman, of the United States Marine Hospital. CALIFORNIA bers — Those who pay $200 and are ah'eady members of the Association. 3. Honorary members — Persons distinguished for original researches relating to tuberculosis, or eminent as sanitarians or as philanthropists, who have given material aid in the study and prevention of tuberculosis. The list of members already numbers two hundred and fifty names, including the leading workers in the subject of tuberculosis, both lay and professional, throughout the country. A fund is being accumulated to insure its financial success. The government of the Association, the planning of work, the arrangements for meetings and congresses, and everything that appertains to legislation and direction, is in the hands of the board of directors, and committees have the power to execute only what is directed by the board. The board of directors is empowered, however, to appoint an executive committee of seven members, of which the president and secretary of the Association shall be ex-ofUcio members, to which is entrusted the executive work of the Association. This committee, chosen at the meeting in Atlantic City, consists of Dr. Edward L. Trudeau, Dr. Henry Barton Jacobs, Dr. William Osier, Dr. Hermann M. Biggs, Dr. Edward O. Otis, Dr. Mazyck P. Ravenel, Dr. Arnold C. Klebs, Dr. John N. Hurty, and Mr. Edward T. Devine. Several pub-Hc meetings have been held, at which talks have been given on the prevention of tuberculosis. Short articles have been placed in daily papers. A pamphlet has been prepared on "Things the Laity should know about Consumption." and a circular of "Precautionary Suggestions for the Afflicted/' Arrangements have been made for the distribution of eightynine thousand of these over Southern Cahfornia, through the schools and in other ways. A lecture bureau is maintained which agrees to furnish lecturers to all organizations that may apply. It is planned to continue and extend the work through the press. Communications should be addressed to either F. M. Pottenger, M. D., President, Monrovia, California, or Rose T. Bullard, M. D., Secretary, Bradbury Building, Los Angeles. Objects: To collect data bearing upon the tuberculosis problem as it exists in the state of California and to make recommendations to the next annual meeting of the Society. Inquiries were sent to everv physician and officer of health in the state and on the answers received the Committee based its report. The report embodied a recommendation to physicians that they should "educate their patients as to the nature of the disease and the manner of its prevention" ; the work done by organizations attempting to combat the disease was endorsed ; and the Committee declared itself opposed to "all forms of phthisiophobia" and to "unscientific, unpractical and inhumane"" legislation, but heartily in favor of the rigid enforcement of antiexpectoration ordinances, the provision of cuspidors in public places, compulsory notification, for the purpose of instruction and disinfection, and state sanatoriums for the poor. localities. ''(b) To institute educational measures. "(c) To secure the adoption of anti-expectoration laws, "(rf) To devise ways and means for securing the disinfection of public vehicles used for the transportation of consumptives, "(-c) To present to the governor and state legislature the matter of the importance and necessity of state sanatoriums for the treatment of the poor.'" school pupils. 7. Secured money from private contributors for the erection of four tent pavilions for the treatment of consumptives. These are attached to the overcrowded Almshouse Hospital — the only hospital in Washington which receives consumptives. GEORGIA A State; Commission was appointed by the governor in August, 1904, to "investigate the extent of tuberculosis in Georgia and means of stamping out the disease." This Commission consists of one physician from each congressional district and ten from the state at large. It will co-operate with the state board of health and also with the recently organized committee on tuberculosis of the State IMedical Association. Its first meeting was held in Macon on October 19. of Dublin. Thk State; Medical x\ssociation has recently appointed a Committee on the Prevention of Tuberculosis of its own members. Literature will be distributed and a tuberculosis exhibit is planned in connection with the next annual meeting of the Association in April, 1905. To educate individuals and the public at large about tuberculosis and its prevention by lectures, printed matter, press articles, and through assistants. To attend to all tuberculosis cases applying for help or treatment at the district ofiices or in their homes, providing medical, nursing, and, to a very limited extent, material aid. ILIvINOIS and house information in regard to cases under the care of the visiting nurse, the dispensary physicians, and other interested physicians. The second is a house catalogue, covering every street in the city, in which may be found the cases reported each week from the Health Department, the County Hospital and free dispensaries, as well as the Cook County Hospital for Consumptives. Maps and charts are on file, giving population, overcrowding and in certain wards the location of cases of tuberculosis. giene, are on file. Sputum is examined for the dispensaries through the generosity of the Columbus Medical Laboratory. Application for disinfection is made to the Health Department, and for removal of cases to the County Agent. Lectures are given to various organizations in all parts of the city. The printed matter issued thus far consists of a Preliminary Report ; a reprint of the set of articles published in the Revieiv of Reviezvs for June, 1903, under the title, "New Hope for Consumptives" ; directions to district physicians and nurses ; and a paper on "Tuberculosis in the Jewish District of Chicago," by Dr. T. B. Sachs. It is planned to distribute leaflets to patients, to placard lodging houses, to increase the efficiency of the dispensaries (see page 155), to open sanatoriums, and to secure an endowment fund for the support of these projects. Object: To secure an appropriation from the legislature for the establishment of a state sanatorium for the care and cure of those suffering from tuberculosis. This committee was appointed at the 1904 meeting of the State Medical Society. Work was begun promptlv by the distribution of a circular on the nature ol tuberculosis, which was largely quoted in the press of the state. As part of the program of educating the public mind to the point of establishing a It is hoped that this project will prove to many who could not otherwise be convinced the correctness of the position that consumption can be cured as easily in Illinois as anywhere else. The support of eight hundred newspapers throughout the state, is assured the Committee in its efforts for securing a state sanatorium. The Anti-Tuberculosis Society oe Indiana (October, 1904) : At the close of a public lecture by Dr. S. A. Knopf this society was organized, with the primary object of securing the establishment of a state institution for the treatment of early cases of tuberculosis. Object: "To investigate the prevalence, distribution and causes of human tuberculosis in the state of Maryland, to determine its relations to the public health and welfare, and to devise ways and means of restricting and controlling said disease." In accordance with these instructions the Commission has imdertaken a census of the tuberculous casts in Baltimore and the state at large; it has made a special study of the cost entailed by the disease in each case, on the individual, his family and the state, as well as of the influence of habits, occvipation and housing conditions. A full account of the results of these investigations and legislative enactments relating to tuberculosis is contained in the recently published report to the governor of the state. A Tuberculosis Exposition was held in Baltimore the week beginning January 25, 1904, under the joint auspices of the Commission and the Maryland Public Health Association. McCoy Hall, at Johns Hopkins University, was converted into a museum, where, by charts, architects' plans, photographs, Hterature, models and other devices, the various kinds of anti-tuberculosis work in progress throughout the United States were displayed. Lectures on important phases of the subject were delivered by leading specialists. The hall was crowded with an enthusiastic audience at every lecture. Eminent physicians and sanitarians were in attendance from the principal cities of the United States and Canada, and it is probable that the total number of visitors during the week amounted to five thousand. The Commission goes out of ofhce by the expiration of the terms of its members in the fall of 1904. A new Commission was appointed by the governor in June, 1904, for a term of two years. Objects : To promote a careful study of conditions regarding tuberculosis in Boston ; to educate public opinion as to the causes and prevention of tuberculosis ; and to arouse general interest in securing adequate provision for the proper care of tuberculous patients in their homes and by means of hospitals and sanatoriums. conditions, occupations, habits and diet. 2. Lectures, particularly to teachers, clergy, and others who will repeat what they hear. Distribution of pamphlets, and of a wall-card for shops telling the results of spitting in improper places. Agitation against such spitting. 3. Extended co-operation with the Board of Health in the removal of patients most likelv to spread consumption. Particular attention to patients discharged from the Sanatorium. 4. An extension of the work among the trades unions. Communications should be addressed to Alexander M. Wilson, General Secretary, 8 Beacon Street, Boston. Objects: To cure, at home if possible, persons suffering with tuberculosis; to relieve with food, as far as possible, all needy tuberculous persons ; to educate the entire community in the prevention and cure of this disease ; to promote the establishment of hospitals for hopeless cases. Under the auspices of the Association a public lecture has been given, at which the attendance was 400. Copies of papers v/ritten by medical experts and pamphlets descriptive of sanatoriums have been placed in the Public Library. Necessary diet and nursing are provided for needy cases reported by physicians. (3) Lectures and the wide circulation of pamphlets in regard to proper nutrition, the value of sunshine and fresh air, exercise, and other subjects allied to the general one of healthful living. The Springfield Association eor the Prevention of Tuberculosis was organized on November 21, 1904, with Dr. H. C. Emerson, 177 State Street, as president. In order to attain these objects the association is working for the better housing of the poor and for well ventilated, clean Avorkshops, stores, and offices ; it is planning public addresses, conferences and printed directions for sick and well. The Association supplies to poor consumptives, through the agency of the Associated Charities, food, clothing, and sputum cups. It assists with money those who would otherwise be unable to be admitted to the State Sanatorium, and is working for the establishment of a place where incurable cases can be cared for at a low rate of board. Dr. A. C. Getchell is the president. of the disease. The work is carried on in conjunction with the local board of health and the dispensaries. Medical treatment is provided through the dispensaries for patients able to go to them. A special nurse has been engaged to visit the homes of poor consumptives in order to instruct them how to care for themselves and how to avoid infecting others, and tO' discover what is needed in the way of diet, disinfectants, and medicines. When the family is not able, financially, to procure these, they are furnished through the Associated Charities. Sputum cups and simple printed information are distributed. The nurse keeps a record of local conditions and a history of the patient's progress. Communications should be addressed to Edwin D. Solenberger, Secretary, 738 Boston Block, Minneapolis. possible. Much care has been given to perfecting the organization of the society. The Executive Committee is a committee of the Civic Improvement League and there are several special committees, as follows : editors of the daily papers. Committee on Inspection, which is made up of sanitarians and ofBcers of the Health Department. Committee of Physicians, on which are representatives of the various schools of medicine. Committee on Consultation, composed of the managers of the principal charitable societies of the city. By public meetings and newspaper articles much general interest has been aroused, and the society intends to carry on an energetic campaign. The plan of action includes the free distribution of leaflets, the enforcement of the anti-spitting ordinance, the organization of a system of inspection and of dispensaries in various parts of the city, a series of illustrated lectures, and the establishment of a sanatorium near the city. NKW HAMPSHIRE, NEW JERSEY passed both branches of the legislature in the January session of 1903, but was vetoed by the governor as a "doubtful and questionable project." An attempt will doubtless T)e made in 1905 to carry through the project. The Report of this Commission, printed at the Rumford Press, in Concord, New Hampshire, is an able presentation of the reasons why a state sanatorium is needed. By a change of figures and geographical names the entire argument becomes applicable to most of the states of the union, and should have a permanent place in the literature of the subject. This society was formed by several physicians. The membership, however, although it includes a large proportion of the physicians of the state, is not confined to them, and the object i.s to interest the public rather than the profession. Literature will be distributed and the public interest will be awakened through the press and by means of lectures. The movement for a state sanatorium, initiated by the New Hampshire Commission (see this page), will be encouraged and furthered in every possible way. .: Objects: i. To disseminate information: a. to those sufifering from the disease, as to best treatment and means of help ; b. to those who come in contact with the disease, as to the prevention of its spread ; c. to the public, as to the subject in general and its bearing on the social life of the community. 2. To secure the co-operation of physicians and nurses in fighting the disease and preventing its spread. 3. To enlist the co- cases in which aid is needed. The Committee's work thus far has resulted in the issue of a circular giving information for consumptives and those living with them; and in the organization, in co-operation with the Orange Memorial Hospital and the Visiting Xurses' Settlement, of a clinic for tuberculous patients. The services of the Diet Kitchen and other charitable organizations have been secured for particular cases in which there was special need ; one public lecture has been given, and articles on the general subject have been contributed to the local press. The work will be carried on and developed in all these directions. • Objects: To maintain a sanatorium for the treatment of consumptives ; to instruct the public in methods of prevention ; to care for, in their homes, such poor consumptives as cannot properly be received in the sanatorium. A site has been selected on a hilltop in the northeastern extremity of the city, and almost enough monev has been subscribed for the buildings. It is hoped that patients can be received this winter. There has been some opposition to the erection of a sanatorium, on the part of interested land-owners, but it has done no more serious harm than somewhat to retard the progress. Objects: The education of the public in regard to tuberculosis, and the relief of poor consumptives; the improvement of the housing of the poor. Active work was begun on May i by the special agent of the committee. During the summer of 1904 most of the time has been given to tenement-house work. Upwards of thirty of the grand jury. On the tuberculosis side the work of the committee has so far consisted of the publication and distribution of many thousand copies, in English, Polish, Italian and German, of cards and pamphlets similar to those issued by the New York Charity Organization Society. The Department of Education has agreed to introduce the committee's literature into the curriculum of the public schools. Prizes of ten and five dollars have been offered in each high school for the best essay on the prevention of consumption. Several public meetings are planned for the winter. Close co-operation has been established with the department of health, and the department has prepared an elaborate map of Buffalo, showing the location of each death from tuberculosis in the last five years. The committee has made a card index of all deaths from tuberculosis and of all living cases of tuberculosis reported to the health department for the last five years. These have been arranged by streets and house numbers, and all houses which show more than one case are reported to the health department for special fumigation. Communications may be addressed to any one of the following: Dr. P. W. Van Peyma, Chairman, 445 William Street; Frederic Almy, Secretary, 165 Swan Street. Objects: i. Research into the social aspects of tuberculosis. 2. Education in means of prevention and proper methods of cure. 3. The advancement of movements to provide special hospitals, sanatoriums and dispensaries for consumptive adults and for scrofulous and tuberculous children. 4. The encouragement of measures which, by improving the conditions of life, tend to decrease the prevalence of tuberculosis. 5. Co-operation with the mvmicipal departments whose heads are members of the Committee and whose work, directly or indirectly, affects the conditions which determine the prevalence of tuberculosis. The results of an investigation into the social aspects of the problem, with special reference to New York City, may be found in full in the Handbook on the Prevoition of Ttiberculosis, published by the Committee as its first annual report. The education of the public in regard to the nature of the disease and the precautions which should be taken to prevent its spread has been undertaken by means of lectures and literature. The lectures during the first two seasons reached an aggregate audience of 20,000. They were delivered in a variety of places and in many different languages. Literature in as great variety has been distributed in large quantities through the city. A manifesto expressing the opinion of the committee in regard to "specifics" and "sure cures" has been widely circulated. The Handbook referred to above includes not only a review of the Committee's origin, scope, and methods of work, but also much of the material collected and prepared for lectures and for publication, and was issued in the hope that it would be of service to those organizing similar movements elsewhere. A considerable part of the efforts of the Committee has been directed tow^ard encouraging movements for increasing dispensary facilities and sanatorium accommodations, by helping to create a popular sentiment on the subject, by co-operation with the Department of Health and the Com.missioner of Charities, and by attempts to influence legislation. The Charity Organization Society, through its regular channels, secures relief for great numbers of persons suffering from tuberculosis, and consequently no direct relief work is done by it through this committee. The Committee has attentively watched proposed legislation bearing on the health of tenement dwellers and has used all its influence against changes in the tenement-house law. It has also opposed a proposition w^hich would have had the effect of decreasing the park area in the crowded districts and has done all that it could to secure the establishment of new playgrounds. During the winter of 1904 the interest of the United Garment Workers of America and the Central Federated Union was aroused, with the result that these two influential labor unions promptly began a campaign among their own members. This feature of the Committee's work is capable of indefinite: extension and holds promise of the most excellent results. public health. In May, 1904, the Association undertook definite work for the prevention of tuberculosis, by opening a hospital for incipient cases (see page 102). As it was impracticable to provide at once suitable hospital accommodations for advanced cases, plans were made for treating them at home. For this purpose the services of a trained nurse have been secured and she began work on September 10. The nurse instructs the patient how to care for himself, and how to protect others by destroying the sputum. She provides sputum cups and paper napkins, and in certain cases milk and eggs. Printed literature on the subject of the prevention of the disease will be provided. The nurse will also provide for and oversee the cleaning and disinfecting of those houses from which tuberculous patients have moved, or in which they have died. The State Tuberculosis Commission was appointed on September 16, 1902, under the authority of a joint resolution passed by the legislature in April of the same year, "to investigate and report upon the feasibility ... of successfully treating persons suffering from tuberculosis, and especially consumption, in sanatoria located within the state of Ohio; also upon the desirability of establishing such institutions." On April 30, 1903, the Commission presented to the Governor a report dealing with the causes of tuberculosis ; its prevalence in Ohio ; the economic loss resulting from it ; the possibility of cure as demonstrated by the experience of German and American sanatoriums ; a comparison of the climate of various points in Ohio, in regard to temperature, precipitation, and weather, with the climatic conditions under which successful sanatoriums are conducted ; the probable cost and the desirable features of site and buildings ; and the results of an inquiry sent to thirty experts in the treatment of consumption, in regard to the character of employment suitable for convalescents. of tubercular patients on a scale sufificiently large to give this subject a fair trial, believing that the outcome will fully justify the expenditure required for such purpose." J. Warren Smith, of Columbus, was the Secretary. Ohio Society for thi: Prevention of Tubercueosis (1902) : Object: To educate the public as to the causes of tuberculosis and the importance of preventing it. Pamphlets have been distributed. A series of articles in regard to the cause, prevention, and cure of tuberculosis has been published in over three hundred daily and weekly newspapers of the state. The appointment of the State Commission which should determine the desirability and feasibility of sanatoriums in Ohio, was secured by this society. It is planned to increase the membership of the society and to continue the educational work. A bill to establish a state sanatorium has been put through the legislature by the Society, a new Commission has been appointed to take charge of selecting a site and building the sanatorium, and $35,000 has been appropriated to begin work. Objects: To prevent tuberculosis: i. By promulgating the doctrine of the contagiousness of the disease. 2. By instructing the public in practical methods of avoidance and prevention. 3. By visiting the consumptive poor and supplying them with the necessary materials with which to protect themselves against the disease, and instructing them in their use. 4. By furnishing the consumptive poor with hospital treatment. 5. By co-operating with boards of health in such measures as they may adopt for the prevention of the disease. 6. By advocating the enactment of appropriate laws for the prevention of the disease. • 7. By such other methods as the Society may from time Since its organization this Society, the first of its kind in America, has contributed to the education of the pubHc by printing and widely distributing six tracts and by holding popular lectures ; it has taken charge of monev to be applied for the support of poor consumptives in hospitals ; it has been instrumental in securing the passage of an anti-expectoration ordinance applying to street cars and railroad offices, and improvement in methods of street-cleaning ; it has used its influence to bring about special provision for the tuberculous patients in the Philadelphia Hospital, and to arouse public sentiment in favor of a state sanatorium ; and it has encouraged the enforcement of pure-food laws by the Pennsylvania Dairy and Food Commission, a matter which affects consumptives indirectly but vitally. It is planned to continue the educational work ; to work for appropriations for several state camps on the forestry reservations similar to the one at Mont Alto, described on page 119; and to assist the Philadelphia Department of Public Safety, in every possible way, in its endeavor to secure registration of cases of tuberculosis and in its work for better sanitary conditions, whether in streets, factories, shops, or dwellings. The offices of the Society are in the Academy of Natural Sciences, of w'hich Dr. Samuel G. Dixon is President, and which is located at Nineteenth and Race Streets, Philadelphia. Communications should be addressed either to the President. Dr. Howard S. Anders, 1836 Wallace Street, or to the Secretary, Dr. Lewis Brinton, 1423 Spruce Street. The Henry Phipps Institute for the Study, Treatment, AND Prevention oe Tuberculosis (Founded February, 1903), 238 Pine Street, Philadelphia: The objects of the Henry Phipps Institute are explicitly stated in its name. It is endowed by ]\Ir. Henry Phipps, of Pittsburg. Dr. Lawrence F. Flick is the medical director, and Dr. Mazyck P. Ravenel is his assistant. The Institute maintains a hospital for advanced cases, a free clinic, and a laboratory for research, all of which are described below. During the winter of IQ03-4 a series of lectures was held, open to the public, and given by speciaHsts of world-wide reputation. Further arrangements for popular lectures and other educational work are being made, and it is planned to The Hospital, 238 Pine Street. For destitute persons in an advanced stage of tuberculosis ; if applicants are able to pay anything they are referred to some suitable place. Six physicians are on duty in the Hospital. The present temporary quarters will be exchanged as soon as possible for buildings better adapted to the work. A training school for nurses is maintained. director of the Institute. In the course of the first year 2,040 cases were treated. Two nurses are employed for inspection of homes, "to see what the patients are doing and give further instructions." Milk is provided at the patient's home when the physician sees fit. Each patient receives verbal, as well as printed instructions. The latter are given in two forms, a folder for the pocket and a large card to hang in the living-room. Sputum cups also are supplied, and Japanese napkins. The laboratory is equipped for original research. The entire medical staff works in the laboratory, under the direction of Dr. ]\I. P. Ravenel, Assistant Medical Director and Bacteriologist. There are also pathological, laryngological, neurological, and dermatological departments connected with the Institute. Applications for admission to the Hospital and inquiries in regard to any part of the work of the Institute should be addressed to Dr. Lawrence F. Flick, Medical Director, 238 Pine Street, Philadelphia. Objects: To provide facihties for the treatment of the consumptives of Scranton, whether in a sanatorium or at a dispensary or in their homes ; and to educate the public by circulars and newspaper articles. At the first meeting after the organization of this society it was decided that the most pressing needs in Scranton were (i) a place where a poor consumptive would have a chance for life, and (2) the prevention of the spread of infection. The Dispensary and Visiting Nurse system (see page 167) were established at once, and work for a sanatorium was begun. In the first year $17,000 was contributed for the work of the society. Within seven months from the date of organization a farm had been bought and a sanatorium building completed (see page 128). The Visiting Nurses care for destitute consumptives too ill to go to the Dispensary, as well as for Dispensary cases needing special attention. They see that sanitary rules are carried out while the patient lives and that the rooms are properly disinfected after a death. A four-page leaflet, called "The Struggle Against Consumption," is published quarterly by the society, for the purpose of keeping contributors and others interested informed in regard to the progress of the work. Objects: The relief of tuberculosis in all its forms and relations. 2. The dissemination of knowledge concerning the causes, treatment, and prevention of tuberculosis. 3. The encouragement of means of prevention and scientific treatment of tuberculosis. RHODU ISLAND, VERMONT The work of the Association is in charge of the following committees : Finance Committee, Dispensary Committee, Milk Committee, Committee on Sputum Cups ; on Education, Lectures, ets. ; on Relief and Care, on Clinic and Hygiene ; and a Committee to inform the teachers and the pupils in public and parochial schools regarding the prevention and spread of tuberculosis. The work has been begun by placing cards regarding spitting in the cars and other public places, by distributing widely a leaflet explaining the "platform" of the Association, and by arranging a public lecture on the subject by Dr. Henry Barton Jacobs. The Committee on Relief and Care has sent to each physician in the city a letter stating its willingness to care for any needy case, with assurances that the physician's instructions will be explicitly followed. All patients in need are furnished by the Association with proper nourishment, as prescribed by the physician. Sputum cups for the room and pocket cuspidors are supplied to all patients. Money is now being subscribed for a temporary sanatorium and for home care. The Dispensary Committee, consisting of five physicians, examines all patients coming under the charge of the Association. If the Committee decides that the case is a hopeful one the patient, if walling, is sent to the camp at Pine Ridge, or, if arrangements can be made, to some sanatorium. Preparations are being made for lectures to the teachers and pupils of the public and parochial schools, and one lecture has been given to the teachers, by Dr. Jacobs. Objects: To investigate the prevalence of tuberculosis in Vermont, and to recommend such measures as may seem advisable to control the disease ; also to submit to the legislature of 1904 plans and suggestions for the location, etc., of a state sanatorium, if such institution should seem desirable. Numerous meetings have been held with the various county medical societies, in order to enlist the support of the medical profession ; important sanatoriums have been visited ; the statistics of deaths from tuberculosis and the climatic characteristics of the state have been studied. It is planned to hold public meetings in all the larger towns of the state, with the object of interesting the people in general in the project of a state sanatorium. A report covering the whole subject will be made to the legislature in 1904. Objects : To encourage the study of tuberculosis in its medical, municipal, and sanitary aspects ; to assist in the establishment and maintenance of a state sanatorium for consumptives ; to disseminate literature and proper information concerning the prevention of tuberculosis and to support all public measures tending to control and limit the spread of the disease." Objects: To investigate the prevalence of tuberculosis in the state and to report to the legislature of 1904 in regard to> the desirability of establishing a sanatorium for the treatment of the disease, with recommendations as to a site. Statistical data as to the prevalence and distribution of the disease in Wisconsin are being collected. A report showing the need of establishing a sanatorium is to be presented to the legislature. An eligible site for its location will be recommended by the Commission, after studying the conditions which should be considered in making such selection. other forms of tuberculosis in Canada : " ( I ) By enlisting the co-operation of the people generally with the medical profession, and by increasing the interest in means for lessening the ravages of the disease; for the prevention of the disease ; "(4) By co-operating with governments and other organizations in measures adopted for the prevention of the disease ; Since its organization the Association has put into circulation T. 250,000 pages of literature relating tO' the cause and prevention of tuberculosis, and lectures have been given by the secretary in about seventy-five towns and cities. Provincial associations, and associations in cities and towns located in provinces in which there is no general organization, are affiliated with the Canadian Association. The affiliated organizations include the Ontario League, the Montreal League, and the St. Francis District League, the Toronto Anti-Consumption League, and the British Columbia Association for the Prevention and Treatment of Consumption. It is planned to continue the work for all objects on an increasingly large scale, as the liberality of the government and of private contributors permits. Objects: To educate the public upon the most simple methods for preventing the ravages of tuberculosis ; to establish, as soon as possible, a home for the incurable cases of the disease, and a sanatorium or sanatoriums for the hopeful cases ; pending the establishment of these institutions, to care for indigent cases in their own homes, in co-operation with the city board of health ; to disinfect every house in which a death from tuberculosis has occurred. During the year ending June, 1904, 200 cases were cared for, 1,300 visits were paid by the inspector, 8,000 cuspidors were distributed, and 30 patients were supported at institutions and given various other forms of assistance. In the course of the seven months between March i and October i, 1904, 359 dismfections were made. Every house in which a death from tuberculosis occurs is visited and formalin disinfection is urged upon the occupant. In nearly all cases the advice is acted upon. A special dispensary for the treatment of tuberculosis has been opened (see page 159). Object : To prevent the spread of tuberculosis, by enlisting the co-operation of the public, by rendering assistance to indigent consumptives, and by promoting desirable legislation. CAN MM Local societies have been formed in each city and town in the district, the chairman of each being a member of the executive committee of the district league. A lecture tour of the district has been made by the secretary of the Canadian Association, in the course of which io,ooo leaflets were distributed. Lectures have been given by physicians on Sunday afternoons in all of the churches and on week days to advanced classes in the public schools and colleges. As a preliminary step toward establishing a free dispensary for consumptives arrangements have been made for two physicians to act as examining and treating physicians for two months at a time. These physicians give their services free to indigent patients. A laboratory is established, where sputum is examined, and where X-ray examinations are made. It is planned to secure the passage of an anti-expectoration law, and to arouse public sentiment for a sanatorium for the consumptives of the eastern townships of Quebec. ment of consumption. The efforts of this League have been devoted to arousing public interest in the establishment of a sanatorium. Through its efforts provincial legislation was secured in 1900 in the form of an act permitting any municipality to establish such a sanatorium and providing that grants may be made from the revenues of the province to the amount of $4,000 for construction and a per capita allowance of $1.50 per week for maintenance. The question of an appropriation of $50,000 by the city was submitted to the people in January, 1904, and approved by a majority of 403 votes, but the appropriation has not yet been made. The League continues its agitation. S. A. Knopf, M. D., James Alexander Miller, M.D., Charles H. Johnson. This volume is a contribution of the New York Charity Organization Society toward the world-wide movement to put an end to the most deadly and most needless scourge with which humanity is afflicted. It is inspired by a confident hope for the success of this movement. The committee aims to diminish, not increase, the hardships of those who are ill; but it insists that it should be the duty of the community to give them a chance to get well while they are curable, and to isolate such as, through carelessness or for other reasons, are really a source of danger to their fellows. From the Preface. The Hatidbook was selected for the Model Public Library exhibited at the Louisiana Purchase Exposition. This library contains a collection of some seven or eight thousand volumes, comprising in proper proportion the best books in every department, as determined by the consensus of a large number of librarians and university specialists. It is also recommended for addition to libraries in the Cumulative Book Index for September, 1904, and the annual bulletin issued by the New York State Library includes it among its list of the 100 best books published in the United States in 1903. interested in public questions should be without it. I think the Handbook on the PreDr. William ventiofi of Tubercttlosis will be of the Osier, greatest service. It contains much have the widest circulation. This book is destined to become one Dr.A. J. Richer, of the most useful publications in the Montreal. anti-tuberculosis movement. It should prove particularly useful for organization work, as it embraces the whole of the subject, treated in a masterly way and by several of the masters. A very commendable feature is that it covers practically every phase of the subject. Fragmentary literature upon the subject of tuberculosis is dangerous. Dr. H. Long= It is one of the most valuable contristreet Taylor, butions to the subject of the suppresSaint Paul. sion of tuberculosis. this important subject for general use that I know of. Not only is the book interesting to Dr.G.W.Holden, medical men as representing the latest Denver. ideas on the prevention of tuberculosis and the necessity of organizing societies to carry out these ideas, but if it can be placed in the hands of the reading public it will materially assist in demonstrating the need for the establishing of sanatoria in every state and city. The public has heretofore had very little information except meagre and sensational newspaper articles ; but in the publications of this society the necessary information is clearly and concisely given by recognized authorities. Worcester, ing knowledge of the subject. It is an able and scholarly work, Jane Addams, presenting in a clear and easily availHull House, able manner the results of recent inChicago. vestigations made by New York ex- perts in medical and social science. Those who have struggled long for cleaner streets and better tenements, for public baths, small parks and playgrounds, will find help and encouragement in this stimulating and interesting record. PRES5 C0nnENT5 The Haiidbook will prove of value American to those who are contemplating similar Medicine. organizations and also as a means of general education. The committee, which consists of sixteen physicians and sixteen laymen, is to be congratulated upon the work accomplished during its first year. This Handbook constitutes one of The Outlook, the most complete and thorough studies of this terrible disease and its prevention that have been published in this country. It contains over three hundred pages, is handsomely printed and illustrated, includes historical, statistical, hygienic and pathological papers by experts, and presents to the reader a valuable bibliography and useful index. We can think of no single work of public philanthropy which is of greater importance or of more widespread public benefit, than such intelligent efforts to check the ravages of tuberculosis as are typified by this Handbook of the Charity Organization Society. The the medical and the sociological side, Churchman. with important illustrations showing both how things are and how they ought to be, gathering together a multitude of useful ideas that have heretofore been scattered in perishable leaflets or in inaccessible reports. Obviously such a book as this is little New York suited for a review dealing in extracts Evening Post, or condensations. It deserves to be read, and no intelligent reader will lay the book down without a feeling of joy that the outlook is so inspiring. There is no human sufferer who needs more to hear the note of hope than the consumptive, and it should be sounded more and more frequently and with greater insistence. It ought to be a great pleasure to every reader to learn that we have now the right to sound this note as never before. It is an attractive volume of three Brooklyn hundred and eighty-eight pages, well Eagle. printed and plentifully illustrated, and covers , in papers by well-known specialssts, most of the phases of the subject on which everyone Jhould be informed. The names of Biggs, Huddleston, sacobi and Knopf, Loomis, Prudden and Trudeau are iufficient guarantee of the book's authority on the medical side, while de Forest, Devine, Folks and others, by their membership in the committee or by contributions to the volume, vouch for its social value. final eradication of consumption. This excellent work should be in the Baltimore hands of every legislator and public Sun. official, of every physician and head of The Handbook on the Prevention of Cleveland Tuberculosis is a timely contribution Leader. to the literature of a subject fast be- coming one of universal interest. This valuable pamphlet should have Pittsburgh wide circulation, not only in view of Telegraph. the need for more general knowledge on the subject of consumption, but by reason of the fullness, clearness and accuracy of the data collected on its pages. It is a comprehensive, nontechnical study of the disease in relation to the causes and treatment. Inter=Ocean. fort to the consumptive and to those who fear' that they may become consumptives through inherited tendency. The book brings comfort and hope San Jose to the consumptive and to those friends Mercury. who anxiously watch the indications of the destructive disease. Dr. Huddleston gives a clear and New Orleans readable description of the germs of Picayune, consumption, how they enter the body, what they do there and what natural protections there are against them. Dr. Biggs and Dr. Prudden write of the causes of tuberculosis and of the methods of preventing and controlling it, while Dr. Knopf points out the duties of different classes of the community and of the government in combating this dread disease. The forms which tuberculosis assumes when it attacks children and the ways of safeguarding them from it, are treated by Dr. Jacobi. Dr. Loomis describes modern sanatorium treatment and discusses the question of climate. A valuable contribution on a much neglected means for fightmg consumption is made by Dr. Miller in his article on the management of such cases in the dispensary. cusses new movements and legislation. In its monthly magazine it continues the weekly news service with fifty or more additional pages of thorough, suggestive matter on the general trend of affairs, conspicuous movements and things accomplished — a fully illustrated monthly magazine. The current events — men, measures, methods — of the movement for the Prevention of Tuberculosis are chronicled every week in brief, labor-saving but comprehensive form. Once or more monthly, longer articles are published, treating specific phases of the problems presented by tuberculosis in different states and cities, invariably written from firsthand information.	54,779	common-pile/pre_1929_books_filtered	directoryofinsti00bran	public_library	public_library_1929_dolma-0010.json.gz:2339	https://archive.org/download/directoryofinsti00bran/directoryofinsti00bran_djvu.txt
S-IGQczoVh2K4SVk	2.29: Introduction to Describing a Distribution	2.29: Introduction to Describing a Distribution What you’ll learn to do: Describe a distribution using mean and standard deviation As important as proper study design, clearly representing data is a fundamental part of a good statistical analysis. In describing a distribution based on quantitative data, we present both numerical and graphical summaries. Putting our previous sections together, we first begin by visually representing the data in a dotplot or histogram. Based on the shape, skew, and outliers, appropriate measures of center and spread help us further understand the distribution. Contributors and Attributions CC licensed content, Shared previously - Concepts in Statistics. Provided by : Open Learning Initiative. Located at : http://oli.cmu.edu . License : CC BY: Attribution	152	common-pile/libretexts_filtered	https://stats.libretexts.org/Courses/Lumen_Learning/Concepts_in_Statistics_(Lumen)/02%3A_Summarizing_Data_Graphically_and_Numerically/2.29%3A_Introduction_to_Describing_a_Distribution	libretexts	libretexts-0000.json.gz:50685	https://stats.libretexts.org/Courses/Lumen_Learning/Concepts_in_Statistics_(Lumen)/02%3A_Summarizing_Data_Graphically_and_Numerically/2.29%3A_Introduction_to_Describing_a_Distribution
H1hn-Qp912ajiKYq	Exploring OER	Intellectual Property, Copyright, & AI There are three areas where AI, copyright, and Intellectual property should be considered: the content that the AI tool has been trained on, the content that the AI tool generates, and using AI to generate summaries of copyrighted content. Use of Content to Train AI Models Many generative AI tools have been trained on copyrighted works often without the permission of copyright holders. Some legal experts have argued that there is a case to be made for fair use, such as in Training Is Everything: Artificial Intelligence, Copyright, and Fair Training and Fair Use: Training generative AI. The arguments they use often revolve around an assertion that it is necessary to conclude that training is fair use to enable this potentially revolutionary new technology. Creative Commons also argues that this is considered fair use under current copyright legislation, but there are a number of lawsuits where creators are arguing that AI tools are creating unauthorized derivatives. Also note that OpenStax currently includes this statement at the bottom of every page of its textbooks, in the Citation/Attribution section: “This book may not be used in the training of large language models or otherwise be ingested into large language models or generative AI offerings without OpenStax’s permission.” See an example in the attributions at the bottom of this page. While one may choose to respect this request, it currently is permissible to engage in such activities as inputting, for example, a chapter from an OpenStax text into ChatGPT to, for example, generate updated content or a chapter summary (see below). Applying Copyright to Generated Output Legal decisions and rulings around copyrighting AI generated content have been very clear in the United States. According to the U.S. Copyright Office, AI generated content is not human made and therefore cannot be protected by copyright and thus is in the public domain. In Canada there has not been as definitive legal rulings around this, although the emerging consensus in Canada is that Canadian copyright law will follow closely with the US when it comes to copyright and AI due to the shared international copyright and trades agreements the two countries have with each other. Using AI to Generate Summaries of Copyrighted Work It is unlikely that using generative AI to summarize copyrighted content is a violation of copyright as the AI generated summary is machine and not human generated. AI and Open Licensing The intersection of AI and open licensing is extremely complex and there is not always agreement as to how, when, or why one can apply an open license when using AI. Getting Started: OER Publishing at BCcampus argues: “As much of the legal consensus around AI generated content suggests AI-created content is not copyrightable, you should not apply a Creative Commons license to AI-generated content as Creative Commons licenses can only be applied to content that is copyrightable.” For more on open licensing, see Units 4 and 8. However, Creative Commons has outlined a variety of ways that its licenses might be used when using AI to create or adapt OER. In Understanding CC Licenses and generative AI, Creative Commons General Counsel Kat Walsh addresses common questions, “while acknowledging that the answers may be complex or still unknown.” The article also includes a flowchart regarding the CC licenses in this context. Citation Examples Here are some examples of ways you might cite output that you generate from AI platforms. The major style guides such as MLA, APA, and Chicago Style now include guidance on citing AI generated content, both in text and in the works cited or bibliography. Example 1 The contents on this page followed by asterisks(*) were adapted from [name of AI platform] output responding to a “[name of prompt],” [Platform version, Date], [AI conversation link]. The remaining original phrases and the organizational structure are by [name of author] and are shared under a [Creative Commons type] license. Example 2 The content of this [content type – article, book, chapter] was written entirely by [human author name(s)] with AI tools [names of platforms/tool(s) used – Grammarly, Bing Copilot, etc] used for [idea generation, copy-editing, etc] and is shared under a [Creative Commons type] license. See below links for the official MLA, APA, and Chicago Style guidelines and their examples for creating generative AI citations. MLA guidelines on citing generative AI APA Style: How to cite ChatGPT Chicago Style General Principles for AI and Open Licensing As of this writing, many legal questions surrounding AI and Intellectual Property are still being considered. As mentioned above, there are many cases pending in the courts in the U.S. as of this writing (July 2024), and there has been only one formal decision by the U.S. Copyright Office and no new law. There was an Executive Order from the Biden White House, but it does not answer the questions that come up about AI and copyright. Here is an overview of some principles currently at the intersection of AI and Open Licensing: - The status of the generative AI materials is, provisionally, clear in the U.S.: they are all born into the public domain, according to the U.S. Copyright Office and one quite specific court decision. - If those conclusions stand, open educators (in the U.S.) can use generative AI materials as they would any other public domain materials in their adopted/adapted/created OER. - Since all of the above is still in flux, open educators should exercise caution when using GenAI materials, for example, by including very complete citations/ attributions which can be used later if the law changes. - Open educators should keep an eye on the outcomes of the many cases about these issues which are in the courts at this time. In general, content - solely created by AI is not copyrightable; it is in the public domain. - containing AI generated elements: only the human created components are copyrightable. - modified by human creativity is copyrightable as a derivative.	1,292	common-pile/pressbooks_filtered	https://pressbooks.utrgv.edu/learnoer/chapter/intellectual-property-copyright-ai/	pressbooks	pressbooks-0000.json.gz:20712	https://pressbooks.utrgv.edu/learnoer/chapter/intellectual-property-copyright-ai/
q6rMJWpGZFB7pvKs	11.6: Electromagnetic Waves (Summary)	11.6: Electromagnetic Waves (Summary) Key Terms \| direction of polarization \| direction parallel to the electric field for EM waves \| \| gamma ray ($\displaystyle γ$ ray) \| extremely high frequency electromagnetic radiation emitted by the nucleus of an atom, either from natural nuclear decay or induced nuclear processes in nuclear reactors and weapons; the lower end of the $\displaystyle γ$ -ray frequency range overlaps the upper end of the X-ray range, but $\displaystyle γ$ rays can have the highest frequency of any electromagnetic radiation \| \| horizontally polarized \| electric field oscillations are in a horizontal plane \| \| infrared radiation \| region of the electromagnetic spectrum with a frequency range that extends from just below the red region of the visible light spectrum up to the microwave region, or from $\displaystyle 0.74μm$ to $\displaystyle 300μm$ \| \| Malus’s law \| $I = I_0 \cos^2\theta$ where $\displaystyle I_0$ is the intensity of the polarized wave before passing through the filter and $\theta$ is the tilt angle of the filter \| \| Maxwell’s equations \| set of four equations that comprise a complete, overarching theory of electromagnetism \| \| microwaves \| electromagnetic waves with wavelengths in the range from 1 mm to 1 m; they can be produced by currents in macroscopic circuits and devices \| \| optically active \| substances that rotate the plane of polarization of light passing through them \| \| polarized \| refers to waves having the electric and magnetic field oscillations in a definite direction \| \| Poynting vector \| vector equal to the cross product of the electric-and magnetic fields, that describes the flow of electromagnetic energy through a surface \| \| radar \| common application of microwaves; radar can determine the distance to objects as diverse as clouds and aircraft, as well as determine the speed of a car or the intensity of a rainstorm \| \| radio waves \| electromagnetic waves with wavelengths in the range from 1 mm to 100 km; they are produced by currents in wires and circuits and by astronomical phenomena \| \| thermal agitation \| thermal motion of atoms and molecules in any object at a temperature above absolute zero, which causes them to emit and absorb radiation \| \| ultraviolet radiation \| electromagnetic radiation in the range extending upward in frequency from violet light and overlapping with the lowest X-ray frequencies, with wavelengths from 400 nm down to about 10 nm \| \| unpolarized \| refers to waves that are randomly polarized \| \| vertically polarized \| oscillations are in a vertical plane \| \| visible light \| narrow segment of the electromagnetic spectrum to which the normal human eye responds, from about 400 to 750 nm \| \| x-ray \| invisible, penetrating form of very high frequency electromagnetic radiation, overlapping both the ultraviolet range and the $\displaystyle γ$-ray range \| Key Equations \| Speed of EM waves \| $\displaystyle c=\frac{1}{\sqrt{ε_0μ_0}}$ \| \| Ratio of E field to B field in electromagnetic wave \| $\displaystyle c=\frac{E}{B}$ \| \| Energy flux (Poynting) vector \| $\displaystyle \vec{S}=\frac{1}{μ_0}\vec{E}×\vec{B}$ \| \| Average intensity of an electromagnetic wave \| $\displaystyle I=S_{avg}=\frac{cε_0E^2_0}{2}=\frac{cB^2_0}{2μ_0}=\frac{E_0B_0}{2μ_0}$ \| \| Malus’s law \| $\displaystyle I=I_0cos^2θ$ \| Summary Maxwell’s Equations and Electromagnetic Waves James Clerk Maxwell (1831–1879) was one of the major contributors to physics in the nineteenth century. Although he died young, he made major contributions to the development of the kinetic theory of gases, to the understanding of color vision, and to the nature of Saturn’s rings. He is best known for having combined existing knowledge of the laws of electricity and of magnetism with insights of his own into a complete overarching electromagnetic theory, represented by Maxwell’s equations. - Maxwell’s prediction of electromagnetic waves resulted from his formulation of a complete and symmetric theory of electricity and magnetism, known as Maxwell’s equations. - The four Maxwell’s equations together with the Lorentz force law encompass the major laws of electricity and magnetism. The first of these is Gauss’s law for electricity; the second is Gauss’s law for magnetism; the third is Faraday’s law of induction (including Lenz’s law); and the fourth is Ampère’s law in a symmetric formulation that adds another source of magnetism, namely changing electric fields. - The symmetry introduced between electric and magnetic fields through Maxwell’s displacement current explains the mechanism of electromagnetic wave propagation, in which changing magnetic fields produce changing electric fields and vice versa. - Although light was already known to be a wave, the nature of the wave was not understood before Maxwell. Maxwell’s equations also predicted electromagnetic waves with wavelengths and frequencies outside the range of light. These theoretical predictions were first confirmed experimentally by Heinrich Hertz. Energy Carried by Electromagnetic Waves - The energy carried by any wave is proportional to its amplitude squared. For electromagnetic waves, this means intensity can be expressed as $\displaystyle I=\frac{cε_0E^2_0}{2}$ where I is the average intensity in $\displaystyle W/m^2$ and $\displaystyle E_0$ is the maximum electric field strength of a continuous sinusoidal wave. This can also be expressed in terms of the maximum magnetic field strength $\displaystyle B_0$ as $\displaystyle I=\frac{cB^2_0}{2μ_0}$ and in terms of both electric and magnetic fields as $\displaystyle I=\frac{E_0B_0}{2μ_0}$. The three expressions for $\displaystyle I_{avg}$ are all equivalent. The Electromagnetic Spectrum - The relationship among the speed of propagation, wavelength, and frequency for any wave is given by $\displaystyle v=fλ$, so that for electromagnetic waves, $\displaystyle c=fλ$, where f is the frequency, $\displaystyle λ$ is the wavelength, and c is the speed of light. - The electromagnetic spectrum is separated into many categories and subcategories, based on the frequency and wavelength, source, and uses of the electromagnetic waves. Polarization - Polarization is the attribute that wave oscillations have a definite direction relative to the direction of propagation of the wave. The direction of polarization is defined to be the direction parallel to the electric field of the EM wave. - Unpolarized light is composed of many rays having random polarization directions. - Unpolarized light can be polarized by passing it through a polarizing filter or other polarizing material. The process of polarizing light decreases its intensity by a factor of 2. - The intensity, I , of polarized light after passing through a polarizing filter is $\displaystyle I=I_0cos^2θ$, where $\displaystyle I_0$ is the incident intensity and $\displaystyle θ$ is the angle between the direction of polarization and the axis of the filter. - Polarization is also produced by reflection. - Brewster’s law states that reflected light is completely polarized at the angle of reflection $\displaystyle θ_b$, known as Brewster’s angle. - Polarization can also be produced by scattering. - Several types of optically active substances rotate the direction of polarization of light passing through them. Contributors and Attributions Samuel J. Ling (Truman State University), Jeff Sanny (Loyola Marymount University), and Bill Moebs with many contributing authors. This work is licensed by OpenStax University Physics under a Creative Commons Attribution License (by 4.0) .	1,501	common-pile/libretexts_filtered	https://phys.libretexts.org/Courses/Kettering_University/Electricity_and_Magnetism_with_Applications_to_Amateur_Radio_and_Wireless_Technology/11%3A_Electromagnetic_Waves/11.06%3A_Electromagnetic_Waves_(Summary)	libretexts	libretexts-0000.json.gz:7638	https://phys.libretexts.org/Courses/Kettering_University/Electricity_and_Magnetism_with_Applications_to_Amateur_Radio_and_Wireless_Technology/11%3A_Electromagnetic_Waves/11.06%3A_Electromagnetic_Waves_(Summary)
Adps4zhh45rphb-d	Macroeconomics	163 State and Local Government Spending Learning Objectives - Describe state and local government spending, including main expenses Although federal government spending often gets most of the media attention, state and local government spending is also substantial—at about $3.1 trillion in 2014. Figure 1 shows that state and local government spending has increased during the last four decades from around 8% to around 14% today. The single biggest item is education, which accounts for about one-third of the total. The rest covers programs like highways, libraries, hospitals and healthcare, parks, and police and fire protection. Unlike the federal government, all states (except Vermont) have balanced budget laws, which means any gaps between revenues and spending must be closed by higher taxes, lower spending, drawing down their previous savings, or some combination of all of these. U.S. presidential candidates often run for office pledging to improve the public schools or to get tough on crime. However, in the U.S. system of government, these tasks are primarily the responsibilities of state and local governments. Indeed, in fiscal year 2014 state and local governments spent about $840 billion per year on education (including K–12 and college and university education), compared to only $100 billion by the federal government, according to usgovernmentspending.com. In other words, about 90 cents of every dollar spent on education happens at the state and local level. A politician who really wants hands-on responsibility for reforming education or reducing crime might do better to run for mayor of a large city or for state governor rather than for president of the United States.	341	common-pile/pressbooks_filtered	https://library.achievingthedream.org/sacmacroeconomics/chapter/state-and-local-government-spending/	pressbooks	pressbooks-0000.json.gz:81591	https://library.achievingthedream.org/sacmacroeconomics/chapter/state-and-local-government-spending/
k_2VHTPwY0WXqdwP	The Study of Astronomy, adapted to the capacities of youth In twelve familiar dialogues, between a tutor and his pupil: explaining the general phænomena of the heavenly bodies, the theory of the tides, &c.	Produced by Eric Hutton and the Online Distributed [Illustration: _Plate I._ The COPERNICAN or SOLAR SYSTEM. _The comparative Distances of the Planets from the Sun_ _T. Conder Sculp^t._] THE STUDY OF ASTRONOMY, ADAPTED TO THE CAPACITIES OF YOUTH: _IN TWELVE FAMILIAR DIALOGUES_, BETWEEN A TUTOR AND HIS PUPIL: Explaining the General PHÆNOMENA of the HEAVENLY BODIES, the THEORY of the TIDES, &c. _ILLUSTRATED WITH COPPER-PLATES._ BY JOHN STEDMAN. _LONDON_: PRINTED FOR C. DILLY, IN THE POULTRY. M.DCC.XCVI. ERRATA. Page 20. line 8. _for_ he _read_ the. —— 22. — 6. ⎫ ⎪ —— 23. — 2. ⎪ — disk — disc. ⎬ —— 42. — last ⎪ ⎪ —— 79. — 5. ⎭ —— 74. — 6. — it axis — its axis. —— 78. — 19. _dele_ Mercury. PREFACE. It has long been a matter of surprize to those who are interested in the education of youth, that, among the numerous publications intended for their improvement, so few attempts have been made to facilitate the study of Astronomy. Many excellent treatises have been written on this important and useful science; but if it be considered that they abound with technical terms, unintelligible to juvenile minds, it cannot be expected that they should derive any great advantage from the perusal of them. To remove these difficulties, the Author has endeavoured, whenever he had occasion to use them, to give such illustrations as to leave no doubt on the young student’s mind respecting their true meaning. The subject appeared to him to be best calculated for dialogues, which are certainly more agreeable as well as more perspicuous to young persons, than the discouraging formality of a treatise. And it is presumed the language will be found natural and easy. In the order he has chosen, he has been careful not to introduce any thing new, till the former part, on which it depends, has been clearly explained. On the whole, it has been his aim to render it as concise and plain as the nature of the subject will admit; and he flatters himself, that at a time when the sciences are so universally studied, the introduction now offered to the public will not be unacceptable. CONTENTS. DIALOGUE I. p. 1. Introduction. Definition. The sun and planets. A globe defined. Sun’s distance and magnitude. Planets, what; their names, periods, and distances from the sun; their magnitudes, compared with the earth; called inferior and superior, why. Comets; derivation of the name. Solar system; why so called. DIALOGUE II. p. 10. Different systems explained. Planets appear like stars; they shine by reflection; how known from stars; they never twinkle, why. Stars shine with their own native light; their inconceivable distance; are suns, the centers of other systems. Plurality of worlds. DIALOGUE III. p. 20. The earth has the appearance of a star to Venus. Remote objects appear at equal distances from us. Our earth is a moon to the moon. The orb of the moon visible soon after the change; her disc and bulk compared with the earth; her mean distance. Sun’s disc compared with hers. Our sun a star, if seen from a planet of another system. Stars as far from each other as the nearest is to us. Stars distinguished by their apparent magnitude. The Milky Way innumerable stars. Number of stars visible at one time to the naked eye. DIALOGUE IV. p. 29. Stars divided into constellations; necessary for ascertaining the situation of the planets, and of the stars with each other. Planets motion regular if seen from the sun; irregular as seen from the earth, the motion being sometimes direct, sometimes retrograde; at others they appear stationary. Superior and inferior conjunction, and opposition, what. Venus has the different phases of the moon. Planets, how distinguished from each other. DIALOGUE V. p. 39. Ecliptic, what. Inclination of the orbits of the planets. Nodes of the planets, what. A plane, what. Planets move in unbounded space. Mercury and Venus seen on the sun’s disc. Number of signs in the zodiac. Zodiac, what. A degree, what. Names of the signs. Number of degrees in each sign. Sun’s place in the ecliptic. Table of signs, their characters, &c. To find the sun’s place in the ecliptic for any day in the year. DIALOGUE VI. p. 50. The orbits of the planets are not true circles, but somewhat elliptical. Perihelion, aphelion, and mean distance, what. Attraction, what. Laws of attraction. Attraction of gravitation, its effects. Simple motion rectilineal. Attractive or centripetal, and projectile or centrifugal forces, what. DIALOGUE VII. p. 61. Bodies moving in circles have a tendency to fly off. Planets kept in their orbits by the joint action of the centripetal and centrifugal forces; they describe equal areas in equal times. Orbits of the comets very elliptical. The earth in its perihelion in December. Equation of time. Center of gravity, what; sun and planets move round it. Sun the center of the system. DIALOGUE VIII. p. 73. The earth revolves on its axis. Cause of day and night. The motion of the earth so uniform as not to be perceived. The apparent motion of the sun caused by the earth’s motion on its axis. An objection to the earth’s motion answered. The sun and some of the planets revolve on their axes. Atmosphere, what; cause of twilight. Horizon, what; the sun and moon appear largest near the horizon, why; they appear above the horizon when below it; caused by refraction; proved by experiment. DIALOGUE IX. p. 87. Inclination of the earth’s axis. An angle, what. The poles, what. Equinoctial, what. Earth’s parallelism described. The axis of the earth points to the same parts of the heavens. Equator, ecliptic, polar circles, and meridians, explained. Difference of time between places lying under different meridians. Longitude, what. How to reduce longitude to time, and time to longitude. Latitude, what. DIALOGUE X. p. 101. The seasons. Vernal and autumnal equinoxes. Days and nights always equal, if the axis of the earth were perpendicular to the plane of its orbit. Seasons occasioned by the inclination of the earth’s axis. Seasons continued. Days and nights equal at all times under the equator. The sun above the horizon of the poles six months; and six months below them alternately, so that they have but one day and one night in the year; the longest day under the polar circles is twenty-four hours. The sun rises on different points of the compass at different seasons of the year. Twilight in the polar regions of long duration. We are nearest the sun in winter, yet it is our coldest season, why. The earth divided into zones; proved to be globular, but is not a true sphere. DIALOGUE XI. p. 120. The moon. Her diameter, synodical and periodical revolutions. Her phases. Has always the same side to the earth, and makes a revolution on her axis every lunation. Has mountains and valleys, but no seas nor atmosphere; yet may be inhabited. Her real and apparent motion described. Eclipses. Of the sun; total and partial eclipses. Digit, what. Eclipse of the moon. Penumbra, what. Central and total eclipse. Why we have not an eclipse at every full and change of the moon. She does not always rise with the sun at change; nor when he sets at full. She is visible when totally eclipsed. DIALOGUE XII. p. 136. Tides. Occasioned by the attraction of the sun and moon, and their centrifugal forces; exemplified by an experiment. Spring and neap tides. Tides not highest directly under and opposite the moon, but after she has passed the meridian. They are later and later every day. Rule for finding the proportional magnitudes of the planets compared with the earth; or the proportion that one globe bears to another. A cube number, what. Table of roots, squares, and cubes; an example. Rule for finding the mean distances of the planets from the sun. Dr. Turner’s rule for extracting the cube root; an example to explain the rule. Example to find the mean distance of Mercury from the sun. Table of diameters, &c. Conclusion. DIALOGUE I. TUTOR. Well, Sir! I suppose this early visit is in consequence of my promise, and your anxiety to become an astronomer. PUPIL. It is, Sir.—And as astronomy is a science of which I have a very imperfect idea, I must beg of you to explain it to me. TUTOR. That I shall do with pleasure. But you surely cannot wholly forget what I have formerly told you. However, as I mean to treat the subject as if you had no previous knowledge of it, you will have an opportunity from what you can recollect, to make such remarks, and ask such questions, as may appear most material to you. PUPIL. I thank you, Sir, it is just what I wish. TUTOR. By astronomy then is meant a knowledge of the heavenly bodies, the sun, moon, planets, comets, and stars, respecting their nature, magnitudes, distances, motions, &c. PUPIL. I fear I shall find it a difficult study. TUTOR. Have patience.—— “The wise and prudent conquer difficulties, “By daring to attempt them. Sloth and folly “Shiver and shrink at sight of toil and danger, “And make the impossibility they fear.” PUPIL. This gives me encouragement, and, if you will have patience with me, I will endeavour to profit by your instructions.——Pray, Sir, what is the sun? TUTOR. The sun, the source of light and heat, has been considered a globe of fire, round which seven other spherical bodies revolve at different distances from him, and in different periods of time, from west by south to east. These are the planets[1]. [Footnote 1: From _Planeta_, roving or wandering.] PUPIL. Any round ball is a globe, is it not? TUTOR. A sphere or globe is defined a round solid body, every part of whose surface is equally distant from a point within called its center; and a line drawn from one side through the center to the opposite side, is called its diameter. PUPIL. You say the sun has been considered a globe of fire. Is he not now thought to be so? TUTOR. [2]Doctor Herschell, from some late observations, is of a different opinion.—But what think you of his magnitude? [Footnote 2: See his letter read at the Royal Society, December 18th, 1794.] PUPIL. I really cannot conjecture.—This I know, that when I saw him through the fog the other day, he appeared about the size of a common plate. TUTOR. You must not always judge by appearances. You will find that there is a material difference between his real and apparent magnitude, which I think you will be convinced of when I tell you, that he is no less than 95 millions of miles from our earth. PUPIL. Ninety-five millions of miles! You astonish me. TUTOR. You will, I dare say, be no less surprized at being told, that he is more than a million of times as large as our earth. PUPIL. It is almost incredible! And what are the planets? TUTOR. The planets are opaque, that is dark bodies, which receive their light from the sun; and, as I told you, revolve about him. The first, or that nearest the sun, is called Mercury, the next Venus, then the Earth, Mars, Jupiter, Saturn, and Georgian, or the Georgium Sidus.[3] These are called primary planets. [Footnote 3: Their characters are, Sun, Merc. Venus, Earth, Mars, Jup. Saturn, Georgian, ☉ ☿ ♀ ♁ ♂ ♃ ♄ ♅ .] PUPIL. Are there then any others? TUTOR. Yes. There are fourteen others, which move round their respective primaries as their centers, and with them round the sun, and are called secondaries, satellites or moons. PUPIL. Have all the primaries secondaries? TUTOR. Only four of them have moons. The earth, I need not tell you, has one; Jupiter has four; Saturn seven, besides a stupendous ring which surrounds his body; and Georgian two. PUPIL. In what time, and at what distances, from the sun, do the planets perform their periodical revolutions? TUTOR. _Mercury_ revolves about the sun in 88 days, at the distance of 36 millions of miles. _Venus_, at the distance of 68 millions of miles, completes her revolution in 224 days. _Earth_, on which we live, at the distance of 95 millions of miles, performs its period in one year.[4] [Footnote 4: The motion of the earth in its orbit is at the rate of 68 thousand miles an hour.] _Mars_, at the distance of 145 millions of miles, in little less than two of our years. _Jupiter_, at the distance of 494 millions of miles, in near 12 years. _Saturn_, at the distance of 906 millions of miles, in about 30 years. _Georgian_, discovered a few years since by Dr. Herschell, performs its period at the distance of 1812 millions of miles, in about 83 years.[5] [Footnote 5: As the distances of the planets, when marked in miles, are a burthen to the memory, astronomers often express their mean distances in a shorter way, by supposing the distance of the earth from the sun to be divided into ten parts. Mercury may then be estimated at four of such parts from the sun, Venus at seven, the Earth at ten, Mars at fifteen, Jupiter at fifty-two such parts, Saturn at ninety-five, and Georgian 190 parts. See Plate I. Fig. 1. These are calculated by multiplying the respective distances of the planets by 10, and dividing by 95, the mean distance of the earth from the sun; and may be set off by any scale of equal parts.] PUPIL. What proportion does the earth bear in magnitude to the other planets? TUTOR. The earth is fourteen times as large as Mercury, very little larger than Venus, and three times as large as Mars. But Jupiter is more than fourteen hundred times as large as the earth; Saturn above a thousand times as large, exclusive of his ring; and Georgian eighty-two times as large. PUPIL. Have you any thing else, Sir, to remark concerning the planets? TUTOR. There are several other things I intend to make you acquainted with, namely, their nature, appearances, motions, &c. At present I shall only say, that Mercury and Venus are called [6]inferior planets, their orbits or paths described in going round the sun, being within that of the earth; and the other four, whose orbits are without the earth’s orbit, [7]superior planets. [Footnote 6: Perhaps with more propriety _interior_ or _inward_.] [Footnote 7: _Exterior_ or _outward_.] PUPIL. There is one thing more I wish to know, if—— TUTOR. I suppose you were going to say if not too much trouble; that is quite unnecessary, as you well know that where I see a desire to learn, teaching is to me a pleasure.—What is it? PUPIL. That you will be so kind as to inform me what the comets are, and if they have any motion? TUTOR. The knowledge we have of comets is very imperfect, as they afford few observations on which to ground conjecture. They are generally supposed to be planetary bodies, forming a part of our system: for, like the planets, they revolve about the sun, but in different directions, and in extremely long elliptic curves, being sometimes near the sun, at others staying far beyond the orbit of the outermost planet; whereas the orbits of the planets are nearly circular. The period of one, which appeared in 1680, is computed to be 575 years. PUPIL. Whence do they derive their name? TUTOR. From _Cometa_, a _hairy star_, because they appear with long tails, somewhat resembling hair: some, however, have been seen without this appendage, as well defined and round as planets. PUPIL. You say _our_ system: what am I to understand by it? TUTOR. The word system, in an astronomical sense, means a number of bodies moving round one common center or point: and, because the planets and comets revolve about the sun, it is called the _Solar System_ (Plate I. fig. 2.); and we say _our_ system, as the earth is one of the planets. Other systems have been invented for solving the appearances and motions of the heavenly bodies, a description of which I shall leave till I next see you. DIALOGUE II. PUPIL. I am afraid, Sir, I am come before you are prepared for me: but the very great pleasure I received yesterday, induced me to be with you as early as possible. TUTOR. I am glad to see you, and happy to find you are so well pleased with your difficult study. It will, I assure you, give you more exalted ideas of the Deity than any that I know of. The Psalmist was undoubtedly of this opinion when he said, The Heavens declare the glory of God, and the Firmament sheweth his handy work. PUPIL. I will no longer call it a difficult, but a pleasing study, and feel myself ashamed at having used the expression. I shall now beg you to explain to me the different systems. TUTOR. The system I have been describing to you was known and taught by Pythagoras, a Greek philosopher, who flourished about 500 years before Christ, as he found it impossible, in any other way, to give a consistent account of the heavenly motions. This system, however, was so extremely opposite to all the prejudices of sense and opinion, that it never made any great progress, nor was ever widely spread in the ancient world. Ptolemy, an Egyptian philosopher, who flourished 130 years after Christ, supposed that the earth was fixed in the center, and that the sun and the rest of the heavenly bodies moved round it in twenty-four hours, or one natural day, as this seemed to correspond with the sensible appearances of the cœlestial motions. This system was maintained from the time of Ptolemy to the revival of learning in the sixteenth century. At length, Copernicus, a native of Poland, a bold and original genius, adopted the Pythagorean system, and published it to the world in the year 1530. This doctrine had been so long in obscurity, that the restorer of it was considered as the inventor. Europe, however, was still immersed in ignorance; and the general ideas of the world were not able to keep pace with those of a refined philosophy. This occasioned Copernicus to have few abettors, but many opponents. Tycho Brahe, in particular, a noble Dane, sensible of the defects of the Ptolemaic system, but unwilling to acknowledge the motion of the earth, endeavoured, about 1586, to establish a new system of his own; but, as this proved to be still more absurd than that of Ptolemy, it was soon exploded, and gave way to the [8]Copernican or true Solar System. [Footnote 8: See Plate I. fig. 2.] PUPIL. I confess, I should have thought with Ptolemy, that the earth was in the center, and that the sun moved round it. TUTOR. You must at present content yourself with knowing that it is not so; and it shall be my business to prove it. PUPIL. May I beg the favour of the information you intended respecting the planets? TUTOR. I will grant it with pleasure. The planets are spherical bodies, which appear like stars, but are not luminous; that is, they have no light in themselves; though they give us light; for they shine by reflecting the light of the sun. PUPIL. You say, Sir, that they appear like stars; if so, how am I to know them from stars? TUTOR. Very easily: for the stars, or as they are more properly called fixed stars, always keep the same situation with respect to each other; whereas the planets, as they move round the sun, must be continually changing their places among the fixed stars, and with one another. PUPIL. Is there any other method of distinguishing them besides what you have mentioned? TUTOR. Yes. The planets never twinkle like the fixed stars, and are seen earliest in the evening and latest in the morning. PUPIL. How is the twinkling of the stars in a clear night accounted for? TUTOR. It arises from the continual agitation of the air or atmosphere through which we view them; the particles of air being always in motion, will cause a twinkling in any distant luminous body, which shines with a strong light. PUPIL. Then, I suppose, the planets not being luminous, is the reason why they do not twinkle. TUTOR. Most certainly. The feeble light with which they shine is not sufficient to cause such an appearance. PUPIL. Have the stars then light in themselves? TUTOR. They undoubtedly shine with their own native light, or we should not see even the nearest of them: the distance being so immensely great, that if a cannon-ball were to travel from it to the sun, with the same velocity with which it left the cannon, it would be more than 1 million, 868 thousand years, before it reached it.[9] [Footnote 9: The distance of Syrius is 18,717,442,690,526 miles. A cannon-ball going at the rate of 1143 miles an hour, would only reach the sun in about 1,868,307 years, 88 days. Adams’s Lectures, vol. 4. page 44.] PUPIL. This is wonderful indeed! what then are they supposed to be? TUTOR. Suns. PUPIL. Suns! the fixed stars suns! TUTOR. Yes, suns. “One sun by day, by night ten thousand shine.” And what will increase your astonishment, each of them is the center of a system of planets, which move round him.[10] [Footnote 10: Dr. Herschell says, that in some clusters of stars he has observed, they appear too close together to admit any planets to revolve about them.] “Observe how system into system runs.” “What other planets circle other suns.” PUPIL. I am almost lost.—I used to think they were designed to give us light. TUTOR. This is a vulgar error.—They were doubtless created for a much nobler purpose, since thousands of them are invisible to us without the help of a telescope; and we receive more light from the moon than from all the stars together. PUPIL. How do you know they are suns? Is their being luminous a proof of their being so? TUTOR. No. But we know that the sun shines with his own light on all the planets belonging to our system; and from what I have told you, have the greatest reason to believe that the stars shine with their own light: we therefore from analogy conclude, that they are so many suns conveying light and heat to other worlds[11]. [Footnote 11: Dr. Herschell thinks it probable that the sun and fixed stars may be inhabited.] PUPIL. Are there then other worlds besides this we live in? TUTOR. Consider.—Has not the earth we inhabit a moon to enlighten it? PUPIL. Yes, Sir. TUTOR. And have I not told you that Jupiter, Saturn, and Georgian, have also moons? PUPIL. This I well remember. TUTOR. For what purpose then do you suppose those orbs were designed? PUPIL. Indeed, I cannot tell. TUTOR. You surely cannot imagine that they were intended for our use, since we knew nothing of them till after the invention of telescopes. PUPIL. That is what I think no one can suppose. TUTOR. And do not all the planets enjoy the benefit of the sun in common with us? PUPIL. Undoubtedly. TUTOR. Well, then; of what use would the light and heat be which is conveyed to them from the sun; or the light which they receive from their moons if there are no inhabitants? PUPIL. I know of none. TUTOR. Can you then have any doubt about their being inhabited? PUPIL. No, Sir.—But you say that the stars are suns, each of which is the center of a system of planets or worlds. TUTOR. If you are satisfied that the planets belonging to our system are inhabited, and that the fixed stars are suns, the centers of other systems, what reasonable objection can you have to all the planets in the universe being so? PUPIL. It is what I cannot comprehend. TUTOR. It may be so.—But is not the same Almighty Power, who does nothing in vain, as capable of making ten thousand worlds if he pleased, as well as one? PUPIL. I will not presume to dispute his power; but are we not told that all mankind descended from Adam? TUTOR. Yes; Moses wrote concerning this earth, he has not made us acquainted with the inhabitants of the other planets: for aught we know they might descend from other Adams.—To-morrow evening, I hope to see you again. DIALOGUE III. PUPIL. I recollect, Sir, you mentioned last night, that the planets appear like stars. Our earth is a planet; how can it have the appearance of a star? TUTOR. If you were on the planet Venus, the earth would have as much the appearance of a star as Venus has to us. PUPIL. But Venus appears amongst the fixed stars. TUTOR. Yes. And so would the earth appear from Venus. PUPIL. How can it be? TUTOR. Because, in whatever part of the universe we are, we appear to be in the center of a concave, that is hollow, sphere, where remote objects appear at equal distances from us: so that, whether we are on the planet Venus or on the earth, in this particular the effect will be the same. PUPIL. Then the light _we_ receive from the sun is by reflection conveyed to the other planets. TUTOR. No doubt of it. And our earth appears as a moon to the inhabitants of the moon, and undergoes the various changes of that planet. PUPIL. Have you any proof of this, Sir? TUTOR. Nothing can be clearer; for, on a fine evening, soon after the change of the moon, when the earth appears nearly as a full moon to the moon, and we see a faint streak of light, the whole body of the moon is visible to us. PUPIL. I remember to have seen it. TUTOR. You do?—The earth then will appear there thirteen times as large as the moon does to us; of course it must reflect a strong light on the body of the moon, and it is by that light we see that part of the moon which is turned from the sun. PUPIL. Is the earth, then, only thirteen times as big as the moon? TUTOR. In solidity it is about fifty times as large; but its disc or face is only thirteen times. PUPIL. What is the moon’s distance from the earth? TUTOR. 240 thousand miles, which is about 400 times less than that of the sun. PUPIL. And yet she appears as far distant as the sun. TUTOR. You are now, I hope, convinced of what I said relative to distant objects. PUPIL. I am, Sir: and I suppose the reason of the moon’s appearing as large as the sun, is because she is so much nearer to us. TUTOR. It is so.—For, at a total eclipse of the sun, which happens when the moon is in a right line between the sun and the earth, the sun is obscured from our sight, although his disc is 160 thousand times as large as that of the moon. In like manner would the moon, when at full, be hid by placing your cricket-ball in a line between your eye and her, yet, you know, the ball is not so large as the moon; but being nearer the eye, it is apparently so. PUPIL. This is very clear. But—— TUTOR. I conjecture you were going to ask me to explain the nature of eclipses. PUPIL. That was certainly my intention, Sir. TUTOR. There are other things you must be made acquainted with before you will be able to comprehend it, and which I will endeavour to make you understand before we enter on the subject. PUPIL. Whenever you please, Sir. TUTOR. You have taken a view of the earth from the planet Venus.—Suppose I transport you to one of the planets belonging to another system; what description do you think you should give of it? PUPIL. I must consider. What I now call a star would be a sun. The planets of that system I should see as I now do those belonging to ours: our sun would be a star; and the earth, with all the other planets, would be invisible. TUTOR. Very well, Sir. Can you then find it difficult to conceive that all the stars are as far from each other in unbounded space as our sun is from the nearest star? PUPIL. It is hard to conceive: but when I consider that wherever I am, every remote object appears at an equal distance from me, the difficulty vanishes. TUTOR. That you might form some idea of the immense distance of the fixed stars, you must recollect, I mentioned the time a cannon-ball would be in reaching the nearest of them. PUPIL. I do, Sir. More than 1,868,000 years. TUTOR. You have an excellent memory. I suppose then you know the distance of the earth from the sun? PUPIL. Yes, Sir. I wrote it down; and, it made so strong an impression on my memory, that I believe I shall never forget it.—95 millions of miles. TUTOR. Now, suppose the earth to be in that part of its orbit which is nearest to the star, it would be 95 millions of miles nearer to it than the sun is. PUPIL. Certainly. TUTOR. And, in the opposite side of its orbit, as much farther from the star. PUPIL. Without doubt. TUTOR. Then you find that the earth is 190 millions of miles nearer to the star at one time of the year than it is at another; and yet the magnitude of the star does not appear the least altered, nor is its distance affected by it. PUPIL. A proof of its amazing distance.—I was going to ask a silly question. TUTOR. What is it? perhaps not so simple as you may imagine. PUPIL. Whether the most conspicuous stars are not supposed to be the nearest to us? TUTOR. Undoubtedly.—And are called stars of the first magnitude; the next in splendor, stars of the second magnitude; and so on to the sixth magnitude; and those beyond, which are not visible to the naked eye, are called telescopic stars. PUPIL. The distance of the telescopic stars must be great indeed, beyond all conception. TUTOR. You judge rightly; and their numbers are beyond all computation. Doctor Herschell says, he has not a doubt but that the broad circle in the heavens, called the Milky Way, is a most extensive stratum of stars, he having discovered in it many thousands. Besides, some stars appear to him double, others treble, &c. not that they are really so, but are stars at different distances from us, which appear nearly in a right line. “As in the milky-way a shining white “O’erflows the heav’ns with one continued light, “That not a single star can shew his rays, “Whilst jointly all promote the common blaze.” PUPIL. I have heard of numbering the stars; but that, I find, is impossible. TUTOR. If you mean that immense host of stars I have been describing, it is impossible; but, though in a clear winter’s night, without moonshine, they seem to be innumerable, which is owing to their strong sparkling, and our looking at them in a confused manner; yet when the whole firmament is divided as it has been done by the ancients, the number that can be seen at a time, by the naked eye, is not above a thousand. PUPIL. Pray, Sir, how did the ancients divide the firmament? TUTOR. I would willingly answer your question; but, as I find I shall not have time to give you that information I wish, I shall postpone it till I see you to-morrow evening. DIALOGUE IV. TUTOR. The ancients, in reducing astronomy to a science, combined the fixed stars into constellations, allowing several stars to make one constellation: and, for the better distinguishing and observing them, they reduced the constellations to the forms of animals, or to the images of some known things, by which means they were enabled to signify to others any particular star they meant to notice. Job mentions two of the constellations, namely, Orion and Pleiades, which shews the study of astronomy to be very ancient. PUPIL. Pray, Sir, how may I know them? TUTOR. By studying the use of the cælestial globe, on which they are drawn. PUPIL. Will you be kind enough to instruct me, Sir? TUTOR. At some future time I probably may: at present you are not prepared for it. PUPIL. I am satisfied.—Have you any thing more to remark of the constellations, Sir? TUTOR. Yes. The situation of the planets, as they are continually changing their places, could not be pointed out without first dividing the stars into constellations: hence, necessity was the mother of invention. PUPIL. And I think a very ingenious one.—If I may be allowed a comparison, I will suppose the different kingdoms of the world on my dissected map, to represent so many constellations; then, if I hear of London, I know it is in England; if of Paris, in France; of Lisbon, in Portugal; and so on. These I would compare with stars of the first magnitude, being the chief cities of their respective kingdoms; inferior cities, stars of the second magnitude; principal towns of the third, &c. TUTOR. A very apt comparison indeed. Now if you hear of a traveller setting off from London to Dover, thence to Calais, Paris, Bern, and so on to Rome, you know that he must go through part of England, Flanders, France, Switzerland, and Italy, passing many towns and villages on his way. PUPIL. That is very evident. TUTOR. Very well, then; in like manner would the planets, if seen from the sun, be traced from star to star, from constellation to constellation, through their whole periods. PUPIL. It is not possible to view them from the sun, surely, is it? TUTOR. No, certainly. PUPIL. Why then do you say if seen from the sun? TUTOR. Because it is there only their motions can appear uniform; as seen from the earth they apparently move very irregularly.—Suppose you were in the center of a circular course; and, whilst a horse was going round, you kept your eye on him: cannot you conceive that you should see him run round the course in a regular manner, moving the whole time the same way? PUPIL. It is not at all difficult to conceive. TUTOR. Again. Imagine yourself placed at a considerable distance on the outside of the course, where you could see the horse the whole time he was going round, would he appear to move as uniformly as before? PUPIL. Certainly not: on the opposite side of the course his motion would be the same as when I stood in the center of it; when he was approaching me, I should scarcely see him move; in that part of the course next to me he would move in a direction contrary to what he did at first; and again when going from me, his motion would be scarcely visible. TUTOR. This I think will give you a tolerable idea of the irregular motion of the inferior planets, as seen from the earth. When farthest from us their motion is said to be direct; when nearest to us retrograde, because they appear to be moving back again; and, when approaching, or going from us, we say they are stationary; because, if then observed in a line with any particular star, they will continue so for a considerable time: now these appearances could not happen if they moved round the earth. PUPIL. Nothing can be plainer: for if the earth were in the center we should always see them move the same way. TUTOR. When the planet is nearest to us, that is in a line between us and the sun, we say it is in its inferior conjunction; when farthest from us, and the sun is between us and the planet, in its superior conjunction. But the superior planets have alternately a conjunction and an opposition. PUPIL. A conjunction, I suppose, when the sun is between the earth and the planet, and an opposition when the earth is between the sun and the planet; that is, when the planet is nearest to us, and appears to be opposite to the sun? TUTOR. You are right.—Therefore, when in conjunction it rises and sets, nearly with the sun; but in opposition, it rises nearly when the sun sets, and sets when he rises. PUPIL. Why do you say nearly, Sir? TUTOR. Because it cannot be exactly, but when the sun, earth, and planet are in a _right_ line, which seldom happens. PUPIL. How do you account for this, Sir? TUTOR. At present I fear you will not be able to comprehend what I wish to explain, as I must use a term you are unacquainted with. The reason is, that the planets are very seldom in or near their nodes at their conjunctions or oppositions. PUPIL. I do not indeed understand what you mean by the word _nodes_. TUTOR. It will be explained to you in due time, and I shall conclude this evening with a few more remarks relative to the appearance of the planets. PUPIL. Any thing you please, Sir. TUTOR. You know that the planets, being opaque bodies, receive their light from the sun; and that only that part which is turned to the sun can be enlightened by him, whilst the opposite side must remain in darkness. PUPIL. This is self-evident: if I hold my ball to the candle it will have the same effect. TUTOR. Tell me then how you think they will appear as seen from the earth. PUPIL. If, when you shewed me Venus, she had not appeared perfectly round, I should say that, both before and after her superior conjunction I should see her nearly with a full face; when stationary, only half enlightened, like the moon at first quarter; because, an equal portion of the dark and bright parts will be turned towards us; the bright part will be decreasing till her inferior conjunction, when the dark side will be turned towards us, and consequently invisible; the light will then increase; and, when she is again stationary, she will appear like the moon at last quarter. TUTOR. When seen through a telescope she has the different appearances you have mentioned; and when I next see you I will shew you that both Venus and Mercury may sometimes be seen when in their inferior conjunctions; the superior planets always appear with nearly a full face. PUPIL. How are the planets distinguished from each other? TUTOR. _Mercury_, from his vicinity to the sun, is seldom seen, being lost in the splendor of the solar brightness. When seen, he emits a very bright white light. _Venus_, known by the names of the morning and evening star, is the brightest, and to appearance, the largest of all the planets; her light is of a white colour, and so considerable, that in a dusky place she projects a sensible shade. She is visible only for three or four hours in the morning or evening, according as she is before or after the sun. _Mars_ is the least bright of all the planets. He appears of a dusky reddish hue, and much larger at some periods than at others, according as he is nearer to, or farther from us. _Jupiter_ is distinguished by his peculiar magnitude and light. To the naked eye he appears almost as large as Venus, but not altogether so bright. _Saturn_ shines but with a pale feeble light, less bright than Jupiter, though less ruddy than Mars. _The Georgium Sidus_ cannot be readily perceived without the assistance of a telescope. DIALOGUE V. TUTOR. Before I proceed to explain what I promised you, it is necessary you should be informed that the earth as seen from the sun, in its periodical revolutions, will describe a circle among the stars which astronomers call the _ecliptic_, and sometimes _the sun’s annual path_, because the sun, as seen from the earth, always appears in that line. PUPIL. Do not all the planets move in the ecliptic? TUTOR. No.—On account of the obliquity of their orbits, they are, in every revolution, one half of their periods above the ecliptic, and the other half below it. PUPIL. I think I comprehend your meaning; but shall be obliged to you, Sir, if you can make it clearer to me. TUTOR. I have here a little design, (Plate II. Fig. 1.) which will answer our purpose: where S represents the sun; ABCD, the orbit of the earth; and EFGH, the orbit of one of the inferior planets, suppose Venus. [Illustration: _Plate II._ _T. Conder Sculp^t._] PUPIL. Now I understand it perfectly: the half EHG rises above, and the other half EFG sinks below it, from the points EG, which I perceive are in a line with the orbit of the earth. But pray, Sir, have you any name for that dotted line? TUTOR. Yes, it is called the _line_ of the nodes; and the points EG the _nodes_ of the planet: the latter is called the ascending node, because, when the planet is in G, it is ascending or rising above the orbit of the earth; or, which is the same thing, above the ecliptic: and when in E, it is descending or sinking below it, whence _it_ is called the descending node. But you must remember that the orbits of all the planets do not cross or intersect the ecliptic in the same points; but that their nodes or intersections are at different parts of it. PUPIL. How can the orbit of the earth and the ecliptic be the same? TUTOR. They are very different; but being in the same plane, if the orbit of any planet inclines to one it must incline equally to the other. PUPIL. You will, I fear, Sir, think me very stupid: but I must beg of you to inform me what you mean by a plane? TUTOR. Any flat surface is a plane. You may therefore suppose the edge of a round tea-table to represent the ecliptic, and a circle within it, drawn from the center of the table, the orbit of the earth: will they not be both in the same plane? PUPIL. Certainly. TUTOR. You must not imagine, when I am speaking to you of the plane of the ecliptic, or plane of the earth’s orbit, that it is a visible flat surface, or, in speaking of the orbits of the planets, I mean solid rings.—No. The planets perform their revolutions with the utmost regularity, in unbounded space; and, like a bird thro’ the air, leave no track behind them. PUPIL. How then are they retained in their orbits? TUTOR. The question, I confess, is natural, and is what I expected; but I must of necessity postpone it to another opportunity; and shall now fulfil the promise I made of shewing you in what manner the inferior planets may be seen when in their inferior conjunctions. Cast your eye again on the little design I gave you, and consider, if Venus were in her ascending node at G, when the earth is at _b_; or, in her descending node, at E, when the earth is at _a_, what the effect would be. PUPIL. She would be in a line with the sun. TUTOR. And, on the sun’s disc, she would appear a dark round spot, passing over it. These appearances, which are called transits, happen very seldom: because she is very seldom in or near her nodes at her inferior conjunctions. There was one in June 1761, one in June 1769; and the next will be in the year 1874. And as Mercury is seen in the same manner, it is a proof that their orbits must be within that of the earth. PUPIL. I thank you, Sir, and shall be obliged to you to inform me how many constellations the earth pastes over in every revolution? TUTOR. Twelve, which correspond with the months of the year, and are called the twelve signs of the zodiac. PUPIL. What is the zodiac? TUTOR. That part of the heavens which contains the twelve signs, and which you may conceive to be a zone or belt extending eight degrees on each side the ecliptic, in which the planets constantly revolve: so that no planet is ever seen more than eight degrees either north or south, that is above or below the ecliptic. PUPIL. What am I to understand by a degree? TUTOR. All circles, whether great or small, are supposed to be divided into 360 equal parts, called degrees, and each degree into 60 equal parts, called minutes: therefore, if I speak of a circle in the heavens, the circumference of the earth, or any other circle, by a degree is meant the 360th part of that circle; and a minute the 60th part of a degree. PUPIL. What are the names of the twelve signs? TUTOR. The first is called Aries, which you know signifies a Ram; Taurus, the Bull; Gemini, the Twins; Cancer, the Crab; Leo, the Lion; Virgo, the Virgin; Libra, the Balance; Scorpio, the Scorpion; Sagittarius, the Archer; Capricorn, the Goat; Aquarius, the Water-bearer; and Pisces, the Fishes. PUPIL. Do you wish me to commit these to memory, Sir? TUTOR. It is very requisite; but as I know you are fond of verse, you shall hear what Doctor Watts says— The Ram, the Bull, the heav’nly Twins, And next the Crab the Lion shines, The Virgin, and the Scales: The Scorpion, Archer, and Sea-goat, The Man that holds the Water-pot, And Fish with glitt’ring tails. PUPIL. I like it much, as it will assist my memory. TUTOR. As the twelve signs correspond with the months of the year, the earth must pass over nearly one degree every day, one sign every month, and in twelve months complete a whole circle, or 360 degrees; therefore every sign must contain 30 degrees, because 30 multiplied by 12 is equal to 360. PUPIL. It must be so. TUTOR. You must remember, that when the earth is in any sign, as seen from the sun, the sun will be in the opposite sign, as seen from the earth: for instance, if the earth be in Aries, the sun will be in Libra; if in Taurus, the sun will be in Scorpio, &c. therefore, as by the earth’s annual motion, the sun _appears_ to move, we always speak of the sun’s, not the earth’s place, in the ecliptic.—You do not seem to understand me? PUPIL. Not perfectly, Sir. TUTOR. Take this orange, and put it in the middle of the round table before us, and place an apple on the opposite side next the window: the orange may represent the sun, the apple the earth, and the window the sign Aries. Now go round the table to the apple; look at the orange, and tell me to what part of the room the eye will be directed. PUPIL. To the part opposite to the window, Sir. TUTOR. If then you suppose the door, which is opposite to the window, to be the sign Libra, the sun will be in Libra when the earth is in Aries—will it not? PUPIL. It is very plain. TUTOR. I shall now give you a table of the signs, their characters, the corresponding months, and the days of the month the sun enters each sign, by means of which, if you reckon a degree for a day, you may find the sun’s place, nearly, for any day in the year. PUPIL. This will give me much pleasure, and I shall be happy to have it. THE TABLE. NORTHERN SIGNS. Aries, Taurus, Gemini, Cancer, Leo, Virgo. ♈ ♉ ♊ ♋ ♌ ♍ March, April, May, June, July, Aug. 20, 20, 21, 21, 23, 23. SOUTHERN SIGNS. Libra, Scorpio, Sagittarius, Capricorn, Aqua. Pisces. ♎ ♏ ♐ ♑ ♒ ♓ Sept. October, November, Decem. Jan. Feb. 23, 23, 21, 21, 20, 18. PUPIL. Why do you write northern and southern signs, Sir? TUTOR. Because they are situated north and south of a circle in the heavens, called the equinoctial, which circle crosses the ecliptic in the points Aries and Libra, and extends 23-1/2 degrees on each side of it; and which I shall have occasion to mention to you another time. PUPIL. When you think proper, Sir, I shall be glad to have it explained to me. TUTOR. Look at your table, and tell me what sign and what degree the sun is in the 30th of March, and 20th of October. PUPIL. The sun enters Aries the 20th of March, of course he must be 10 degrees in that sign the 30th; and, as he does not enter Scorpio till the 23d of October, he must want three degrees of completing the sign Libra; he must therefore, on the 20th of October, be in 27 degrees of Libra. TUTOR. Very well.—Do you learn the table, as you will have a farther use for it. DIALOGUE VI. PUPIL. Since I was last with you, Sir, I have been thinking of what you then told me, that the planets perform their revolutions in open space: I have not the least idea how this can be; if convenient, I shall be happy to have it explained. TUTOR. It will be necessary first to inform you, that the orbits or paths described by the revolution of the planets round the sun, are not true circles (as Plate II. fig. 2.) but somewhat elliptical, that is, longer one way than the other, as fig. 3. PUPIL. This is exceedingly plain. TUTOR. In a circle, the periphery or circumference is equally distant from a point within called its center, as A; but an ellipsis has two points called the focuses or foci, as B C. In one of these, called its lower focus, is the sun: so that you see in every revolution of the planet it must be nearer to the sun in one part of its orbit, than it is in another. PUPIL. I see it clearly. TUTOR. Now let S (Plate II. fig. 4.) represent the sun, A B C D a planet in different parts of its orbit; when it is nearest to the sun, as at A it is said to be in its _perihelion_; when at B its _aphelion_; but when at C or D its middle or mean distance, because the distance S C or S D is the middle between A S the least and B S the greatest distance; and half the distance between the two focuses is called the _eccentricity_ of its orbit, as S E or E F. PUPIL. This I will endeavour to understand; but I find it will take me some time to be perfected in it. TUTOR. You may study it at your leisure, as it will not prevent our proceeding to the thing proposed, namely, the laws which govern the motion of the planets, or ATTRACTION OF GRAVITATION. PUPIL. By attraction I think you mean that property in bodies whereby they have a tendency to approach each other. I remember you told me that the magnet I had the other day attracted the needle. TUTOR. Yes. And you may recollect that when I took a feather suspended by a thread, and put it near the conductor of the electrical machine, it was strongly attracted by it, and adhered to it as long as the machine was kept in motion. PUPIL. I remember it well. But what am I to understand by attraction of gravitation? TUTOR. The sun, being the largest body, _attracts_ the earth and all the other planets, they _gravitate_ or have a tendency to approach the sun; the earth being larger than the moon _attracts_ her, and she _gravitates_ towards the earth; the planets are attracted by and gravitate towards each other; a stone when thrown from the earth, by its attraction and the gravitating power or weight of the stone, is brought to the earth again; the waters in the ocean gravitate towards the center of the earth; and it is by this power we stand on all parts of the earth with our feet pointing to the center. PUPIL. This information affords me great pleasure. TUTOR. Having mentioned attraction of magnetism, electricity, and gravitation, it may not be amiss to inform you of another kind, called _attraction of cohesion_. PUPIL. Any thing which tends to my improvement, I shall be obliged to you to communicate. TUTOR. By attraction of cohesion is meant that property in bodies which connects or firmly unites the different particles of matter of which the body is composed. PUPIL. Pray, Sir, inform me what you mean by the _laws_ of attraction? TUTOR. You are to understand, 1st. That _attraction decreases as the squares of the distances between the centers of the attracting bodies increase_. PUPIL. I must beg you, Sir, to explain to me the meaning of the squares of the distances. TUTOR. Any number multiplied into itself is a square number, thus 1 is the square of 1; 4 is the square of 2; 9 is the square of 3, and so on, because 1 multiplied into itself is 1; 2 by 2 is 4; 3 by 3 is 9, &c. Now suppose, that when the planet is at B (Plate II. fig. 4.) it is twice as far from the sun as it is at A: how much more will it be attracted by the sun at A than at B? PUPIL. You say, Sir, that the distance is twice as great at B as at A? TUTOR. I do. PUPIL. Then as the square of the distance 2 is 4, the decrease of attraction at B, the planet at A will be attracted with four times the force it would be at B.—Am I right, Sir? TUTOR. Perfectly so. And if the distance at B were three times as great as at A, it would be attracted with a force nine times as great. PUPIL. I perceive it must be so. TUTOR. I shall now give you the 2d law, namely, That _bodies attract one another with forces proportionable to the quantities of matter they contain_. PUPIL. Do all bodies of the same magnitude contain equal quantities of matter? TUTOR. No, certainly: For a ball of cork may be as large as one of lead, and yet not contain the same quantity of matter, because it is more porous, and not so compact or dense a body as the lead; neither will a ball of lead of the same magnitude as one of gold contain an equal quantity of matter.—So the sun, though a million of times as big as the earth, contains a quantity of matter only 200,000 as great, therefore attracts the earth with a force 200,000 as great as the earth attracts him. PUPIL. I think this is clear. TUTOR. We will now suppose that in the river are two boats of equal bulk, at the distance of twenty yards from each other, and that a man in one boat pulls a rope which is fastened to the other, what effect will be produced, or where do you think the boats will meet? PUPIL. Had you not told me that bodies attract one another with forces which are proportioned to the quantities of matter they contain, I should say the boat to which the rope is fastened would come to that in which the man stands: but as I imagine you mean to apply this to attraction, by the above rule, they will meet at a point which is half way between them. TUTOR. If one boat were three times the bulk of the other, how then? PUPIL. The lightest would move three times as far as the heaviest, or 15 yards whilst the heaviest moved only 5. TUTOR. Upon my word you reason philosophically. In both cases you are perfectly right. PUPIL. As the sun is so immense a body that his quantity of matter is so much greater than the planets, I am at a loss to know why they are not by the power of attraction drawn to him. TUTOR. And so they would if the attractive power were not counteracted by another of equal force. PUPIL. Did you not say, Sir, that the planets are kept in their orbits by attraction? TUTOR. I did. But you find that by attraction _only_ the sun would draw all the planets to himself. PUPIL. That is evident. But I wish to know what this counteracting power you speak of is? TUTOR. I will tell you presently.—You must remember that _simple_ motion is naturally rectilineal, that is, all bodies, if there were nothing to prevent them, would move in strait lines. PUPIL. Then as the planetary motion is circular, it cannot be simple? TUTOR. No. It is a _compound_ of the two forces I have been mentioning: the one is called the attractive or centripetal force; the other, the projectile or centrifugal force. PUPIL. The former I clearly comprehend, but not the latter. I can conceive, that if two bodies approach each other by attraction they must move in a right line. TUTOR. If you shoot a marble on a smooth piece of ice, in what direction will it run? PUPIL. Strait forward. TUTOR. This is a projectile force.—Could you, do you think, shoot it in any other direction? PUPIL. No, Sir. TUTOR. Then is not this motion also rectilineal? PUPIL. It is. TUTOR. When you strike a ball with your cricket-bat, or throw a stone with your hand, is it not projected or thrown forward by the force of the bat or hand? PUPIL. Certainly. TUTOR. And does it not move in a strait line? PUPIL. At first it appears to do so; but afterwards it inclines towards and falls to the earth. TUTOR. Cannot you account for this? PUPIL. I suppose it must be drawn to the earth by attraction. TUTOR. You are right. The attraction of the earth, and the resistance of the atmosphere or air through which it moves, retards its progress, or it would continue moving in a strait line, with a velocity equal to that which was at first impressed upon it. In like manner the beneficent Creator of the Universe impressed a force on all the planets which should be equal to that of the attractive power of the sun, that one might not overcome the other. PUPIL. This wants explaining. TUTOR. I would willingly gratify you, but as I have much more to say on the subject, I fear it will be too great a burthen on your memory; it will therefore be better to postpone it. PUPIL. As you please, Sir. DIALOGUE VII. TUTOR. Having at our last meeting explained to you the nature of the attractive and projectile forces, I shall proceed to shew you that it is by the joint action or combination of these two forces that the planets are retained in their orbits. PUPIL. I am all anxiety, as I wish to be informed how, or in what manner they can act against each other, to produce that effect. TUTOR. Answer me a few questions, and you will soon know. PUPIL. As many as you please, Sir. TUTOR. If you whirl a stone in a sling, what will be its motion? PUPIL. Circular. TUTOR. Is you let it suddenly slip out of the sling, will it continue its circular motion? PUPIL. No, Sir, but fly off in a strait line. TUTOR. This line you must remember is what mathematicians call the tangent of a circle, as A _a_, B _b_, &c. (Plate II. fig. 5.) for all bodies moving in a circle have a natural tendency to fly off in that direction. Thus a body at A will tend towards _a_; at B towards _b_, and so on; but the central force acting against it preserves its circular motion. PUPIL. By the central force here you mean the action of the hand, do you not? TUTOR. Yes. For, as soon as the stone is released and that power is lost, it assumes its natural, that is, its rectilineal motion.—Again. If you are left at liberty, cannot you run strait forward? PUPIL. Yes, Sir. TUTOR. Now, suppose one of your companions were to fasten a rope round your body, and at the extent of it were to stand still and hold it tight, with a force equal to that with which you run, could you, do you think, move in a strait line, that is, in a tangent of a circle? PUPIL. No, Sir. I must run in a circle. TUTOR. Why? PUPIL. Because, whilst the rope is extended I am prevented running in any other direction. TUTOR. Just so it is with the planets: the attractive or centripetal force of the sun being equal to that of the projectile or centrifugal force of the planets, they are by attraction prevented moving on in a strait line, and, as it were, drawn towards the sun; and by the projectile force from being overcome by attraction. They must therefore revolve in circular orbits. PUPIL. What I have so long wished is now accomplished. I understand it perfectly. TUTOR. What I have now explained relates not only to the primary planets which have the sun for their center of motion; but, you must remember that the secondary planets are governed by the same laws, in revolving about their respective primaries; for, as by the attractive power of the sun combined with the projectile force of the primary planets they are retained in their orbits; so also the action of the primaries upon their respective secondaries together with their projectile force, will preserve them in their orbits. PUPIL. Pray, Sir, what have you else to observe? TUTOR. Have I not told you that the orbits of the planets are not true circles, but a little elliptical? PUPIL. Yes, Sir; and I shall be glad to know the reason of it. TUTOR. If the attractive power of the sun were uniformly the same in every part of their orbits they would be true circles, and the planets would pass over _equal_ portions of their orbits in _equal_ times; that is, they would move from B to C, (Plate II. fig. 5.) in the same time as from A to B, &c. PUPIL. That is clear, but as their orbits are elliptical, when the planets are farthest from the sun, the velocity with which they move must be lessened as the attraction is decreased. TUTOR. And they must consequently pass over _unequal_ parts of their orbits in _equal_ portions of time. And, as _a double velocity will balance a quadruple or fourfold power of gravity or attraction_, it follows, that as the centripetal force is four times as great at A as at B (Plate II. fig. 4.) the centrifugal force will be twice as great, and would carry a planet from A to _a_ in the same time it would from B to _b_, and in its orbit from A to _c_ as soon as from B to _d_, and thereby describe the area, or space contained between the letters A S _c_, in the same time as the area or space B S _d_. For according to the laws of the planetary motions, in their periodical revolutions, _they always describe equal areas in equal times_. PUPIL. The orbits of the comets being very elliptical, the irregularity of their motions must be exceedingly great. TUTOR. Great, indeed!—One of them passed so near the sun as to acquire a heat which Sir Isaac Newton computed to be two thousand times hotter than red hot iron.[12] [Footnote 12: Dr. Herschel is of opinion, that bodies near the sun do not acquire so great a degree of heat as has been generally imagined.] PUPIL. Astonishing! If they pass so near the sun, the centripetal force must act powerfully on the body of the comet. TUTOR. And that force, you know, must be equalled by the projectile force; so you find they move when near the sun with amazing celerity.—But when arrived at their aphelion, where the influence of the sun is weak, what a transition! PUPIL. Wonderful, indeed!—Their motion is excessively slow, and the sun must appear little more than a fixed star. Surely they cannot be inhabited, can they? TUTOR. We cannot speak positively; but, as they differ so much from the planets, which we have reason to suppose are so, it is imagined they are designed for some purpose unknown to us. PUPIL. When is the earth in its perihelion? TUTOR. In December; and our summer half year is longer than the winter half, by about eight days. PUPIL. I suppose this is occasioned by the inequality of the earth’s annual motion. TUTOR. It is; and this inequality is the cause of the difference of time between the sun and a well regulated clock; the latter keeps equal time, whilst the former is constantly varying. PUPIL. I have often seen in the almanack clock fast, clock slow, but did not know the meaning of it: I imagine it is that the clock should be so much faster or slower than the time by the sun as is there mentioned. TUTOR. It is: but there are tables calculated to shew the difference of time for every day in the year; so that if you know the exact times of the day by the sun, and have one of these tables, you will see what the time should be by the clock, to a second, which is not shewn in a common almanack. PUPIL. In speaking of the annual or yearly motion of the earth, you have no where mentioned the cause of the seasons; will it be agreeable to do it now, Sir? TUTOR. The vicissitudes of the seasons, the cause of day and night, &c. shall be the subject of future lessons: we shall find sufficient to employ us at present. PUPIL. I think you told me just now that the earth is nearest the sun in December; that is our winter; this seems a little mysterious. TUTOR. It may appear so to you now, by-and-by you will be of a different opinion. I shall explain this matter to you with that of the seasons, &c. PUPIL. I fear I have interrupted you.—As you said you had sufficient employment for us, I shall be glad to know what it is. TUTOR. Hitherto I have spoken of the sun’s being fixed, and that the planets revolve about him as a center. Instead of which the sun and planets move round one common center, called the center of gravity. PUPIL. What is this center of gravity? TUTOR. Have you never seen a person raise a heavy weight by means of a long pole or leaver, which it was not in his power to lift without it? PUPIL. Yes, Sir, and it excited my astonishment. TUTOR. Now, suppose the weight to see raised to be 10 Cwt. and the prop on which the leaver rested 1 foot from the body to be raised; and the person at the other end of the leaver 10 feet from the prop; with what weight must he press to raise the 10 Cwt.? PUPIL. I think that very easy; for, as he is ten times as far from the prop as the weight is, a pressure of 1 Cwt. which is one-tenth of the weight to be raised will do it. TUTOR. To be sure; and yet you say you were astonished when you saw it! Every thing we do not understand at first appears difficult.—To apply this to our present purpose. You see that a weight of 1 Cwt. at 10 feet from a prop, will balance another of 10 Cwt. at one foot from it. Now, instead of a prop let the two weights be nicely poised on a center, round which they may freely turn; the heaviest would move in a circle, whose radius, or distance from the center would be one foot, whilst the lightest would move in one 10 feet from the center in the same time. PUPIL. Is the center round which they move the center of gravity? TUTOR. It is; and round an imaginary point as a center the sun and planets move, always preserving an equilibrium. If the earth were the only attendant on the sun, as his quantity of matter is 200,000 times as great as that of the earth, he would revolve in a circle a 200,000th part of the earth’s distance from him, in the same time as the earth is making one revolution in its orbit, or in one year; but, as the planets in their orbits must vary in their positions, the center of gravity cannot be always at the same distance from the sun. PUPIL. If it were, the balance could not be preserved. TUTOR. Clearly so. But you must know that the quantity of matter in the sun so far exceeds that of all the planets together, that even if they were all in a line on one side of him he would never be more than his own diameter distant from his center of gravity; therefore, astronomers consider the sun as the center of the system, and express themselves accordingly. PUPIL. As you told me the secondary planets are governed by the same laws as the primaries, I imagine they also with their primaries move round a center of gravity. TUTOR. They do so.—The earth and moon, Jupiter with his satellites, Saturn and his attendants, revolve about their respective centers; these, with the sun and the rest of the planetary system, make their circuits round their center; every system in the universe is supposed to revolve in like manner; and all these together to move round one _common center_.—How are we lost in contemplating the omniscience of the Deity! How difficult to conceive so many millions of bodies of dead matter constantly in motion, so nicely balanced and governed by such unerring laws!—Well may we say with the Psalmist, “Lord! how manifold are thy works, in wisdom hast thou made them all.” DIALOGUE VIII. TUTOR. I shall now, agreeably to my promise, explain to you the cause of day and night, and then proceed with the vicissitudes of the seasons. PUPIL. That is what I much wish to know; and had you not told me that the earth moved round the sun every year, I should have found no difficulty in accounting for the succession of day and night, since the sun appears to rise and set every day. TUTOR. That is true; but I think I must have convinced you that so immense a body as the sun cannot revolve about the earth; as well may you suppose that in roasting a bird it is necessary that the fire should move round it. PUPIL. That I think would be very absurd, as it is much easier for the bird on the spit to turn to the fire, than for the fire to go round the bird. TUTOR. You are certainly right, and if the earth revolve on its axis every twenty-four hours, will not the different parts of it be alternately turned to the sun, as the bird on the spit is to the fire? PUPIL. I do not clearly comprehend what you mean by the axis of the earth; for, as it moves in open space and has no support, it can have nothing to resemble the spit on which it turns. TUTOR. Certainly not. By the earth’s axis is meant an imaginary line passing through its center, on which it is supposed to turn; as your ball if rolled on the ground would revolve on an axis whilst it was moving forward. PUPIL. I can now answer your question in the affirmative: and, as our year consists of 365 days, I imagine the earth must make as many revolutions on its axis whilst it is going once round the sun. TUTOR. Undoubtedly: and as only one half of a spherical body can at any time be enlightened by a luminous body, that part of the earth only which is turned to the sun, can receive the benefit of his enlivening rays, when it will be day; whilst the opposite part will be involved in darkness, and it will be night. PUPIL. I perceive it must be so. But, if the earth move in the manner you describe, I cannot conceive how it is that we are not sensible of its motion. TUTOR. If the motion of the earth were irregular it would be perceptible; but as it meets with no obstruction the motion must be so uniform as not to be perceived. PUPIL. Had I recollected this, I need not have given you this trouble.—But I am continually meeting with fresh difficulties. TUTOR. You have only to mention what they are, and I shall take a pleasure in removing them. PUPIL. I thank you, Sir; and shall be obliged to you to inform me, how the motion of the earth can cause the sun to appear to move? TUTOR. When in a carriage which went smoothly on the road, or in a boat whose motion was scarcely perceptible on the water, did you never fix your attention on the objects you passed? PUPIL. Yes, often, Sir. TUTOR. And had you not known that you really moved, and that the trees, &c. were immoveable in the ground, what then would have been your opinion? PUPIL. That the trees, &c. moved in a direction contrary to that in which I was moving. TUTOR. Is not this sufficient to convince you that the apparent motion of the sun may be occasioned by the revolution of the earth on its axis? PUPIL. It is:—But if so large a body as the earth make a revolution on its axis in 24 hours, it must move with great velocity. TUTOR. It does so; and the inhabitants of London by this motion are carried at the rate of 560 miles an hour[13]. [Footnote 13: The hourly motion under the equator is 900 miles.] PUPIL. What an astonishing rapidity! TUTOR. Now, the sun with the rest of the heavenly bodies must move round the earth, or the earth must revolve on its axis in 24 hours, to cause that appearance. PUPIL. That is plain. TUTOR. Well then, great as you may suppose the velocity of the earth on its axis to be, if the sun move round the earth his hourly motion will be nearly 25 millions of miles; and beyond conception would be that of the fixed stars. Which now do you think is most probable, that the sun and stars should move round the earth, or that they, by the simple motion of the earth, should appear to be in motion? PUPIL. The latter, to be sure, Sir.—I have one difficulty remaining, which is this; if a lark rise from a field near London and remain in the air a quarter of an hour, if the earth move at the rate of 560 miles an hour, it will go 140 miles whilst the lark is suspended, and yet it continues over the field,—how can this be? TUTOR. This objection to the motion of the earth has been made by those who were older and who thought themselves wiser too than yourself. They either did not know or did not consider, that the atmosphere which surrounds the earth is a part of itself, and gravitates towards it, and therefore partakes of the earth’s motion and carries the lark along with it. Besides, as the Sun, Venus, Mars, and Jupiter are known to revolve on their axes, we have reason to suppose that the other planets, together with the earth, must have the same motion[14]. [Footnote 14: Dr. Herschell says that several of the fixed stars revolve on their axes.] PUPIL. How is it known that they do revolve on their axes; and in what time do they perform their revolutions? TUTOR. By the assistance of telescopes dark spots have been seen on the disc of the sun, by the motion of which it is found that he revolves on his axis in 25-1/4 days; Venus performs her diurnal revolution in about 23 ho. 21 min.; Mars goes round his axis in 24 ho. 39 min.; and Jupiter in 9 ho. 56 min.; as to the rest, no spot or any fixed point has been discovered to ascertain the length of their day; Mercury being too near the sun, and Saturn and the Georgium Sidus too remote for our observations. PUPIL. I can no longer doubt of the earth’s motion: and, if it will not be improper, a description of the atmosphere will give me pleasure. TUTOR. That I can have no objection to. The atmosphere is a thin, invisible fluid, most dense or heavy near the earth, but grows gradually rarer or lighter the higher we ascend, so much so, that at the tops of some high mountains it is difficult to breathe. It serves not only to suspend the clouds, furnish us with wind and rain, and answer the common purposes of breathing, but is also the cause of the morning and evening twilight, and of all the glory and brightness of the firmament. PUPIL. How, pray? TUTOR. If there were no atmosphere, the sun would yield no light but when our eyes were directed towards him; and the heavens would appear dark and as full of stars as on a dark winter’s night; but the atmosphere being strongly illuminated by the sun, reflects the light back upon us, and makes the whole heavens to shine so strongly, that the faint light of the stars is obscured, and they are rendered invisible. PUPIL. I find then the atmosphere is of more use than I imagined. But how is it the cause of the twilight? TUTOR. The atmosphere is about 45 miles above the surface of the earth, therefore the sun’s rays falling upon the higher parts of it before rising, by reflection causes a faint light, which increases till he appears above the horizon; and in the evening it decreases after he sets, till he is 18 degrees below the horizon, where the morning twilight begins, and the evening twilight ends. PUPIL. By the horizon, I think you mean that distant boundary of our sight where the heavens and the earth seem to join all around us, as it appears from an eminence. TUTOR. The very same. ’Tis that imaginary circle which intercepts from our view the sun, moon, and stars each night; and when, by the rotation of the earth, they appear to descend below it, we say they are set; as on the contrary, each morning, when they appear above it, we say they rise. “To find the spacious line, cast round thine eyes, “And where the earth’s high surface joins the skies, “Where stars first set, and first begin to shine, “There draw the fancy’d image of this line.” PUPIL. A very pleasing description, indeed. TUTOR. You will remember that this is called the _rational horizon_; but that which respects land and water is called the _sensible horizon_. The former divides the heavens into two equal parts, and is 90 degrees distant from a point directly over our heads, called the _zenith_, and the opposite point of the heavens directly under our feet, called the _nadir_.—But I must resume the subject of the atmosphere. PUPIL. Had I not thought you had finished your description of the atmosphere, I should not have presumed to interrupt you. TUTOR. What I have told you respecting the horizon is necessary for you to be acquainted with; therefore, the suspension is immaterial.—You must, I make no doubt, have observed the sun and moon at rising and setting to appear larger than when higher above the horizon. PUPIL. I have, frequently, Sir. TUTOR. And cannot you tell the reason of it? PUPIL. No, Sir. TUTOR. The reason is this: In viewing them, when near the horizon, you see them through a thicker medium than when they are higher, that is, you see them through a greater quantity of the atmosphere; and you not only see them larger, but really above the horizon whilst they are actually below it. PUPIL. How do you account for this, Sir? TUTOR. Light, like material bodies, if it meet with no obstruction, will move in right lines; now, the rays of the sun in coming to the earth must pass through a great quantity of the atmosphere, which being a fluid, refracts or bends the rays of light, by which refraction it is that we are favoured with the sight of the sun 3-1/4 minutes every morning before he rises above the horizon, and every evening after he sinks below it, which in one year amounts to more than 40 hours. This refraction is greatest near the horizon, and ends in the zenith. PUPIL. Pray, Sir, can you make this clearer by an experiment? TUTOR. I have just thought of one. Take a bason filled with water, and a strait stick or piece of wire; put it perpendicularly into the water, that is, that it lean neither way, and there will be no refraction; incline it a little towards the edge of the bason and it will appear a little bent at the surface of the water; incline it still more, and the refraction will be greater. PUPIL. I have often seen this appearance when I have put my stick into water, but did not before know the cause. TUTOR. You may try one more experiment. Pour the water out of the bason, and set the bason on the floor; put a guinea into it, and let it represent the sun.—Why do you smile? PUPIL. Because I have not the sun’s representative to try the experiment with. TUTOR. Well, well, put a shilling into the bason and call it the moon, and it will answer the same purpose:—Walk backward till you just lose sight of it, then the right line from your eye continued over the edge of the bason must pass beyond the money at the bottom of it. PUPIL. That is evident. TUTOR. Keep your position, and desire some friend to pour the water gently into the bason so as not to remove the money, and you will clearly distinguish it. Now, if you call the edge of the bason the horizon, the water the atmosphere, and the shilling the moon, is it not clear that you will see it above the horizon, when it is really below it? PUPIL. I think so, Sir. TUTOR. Well, try the experiment, and let me know the result when I next see you. DIALOGUE IX. TUTOR. I presume, Sir, you have made the experiment I recommended to you. PUPIL. I have, Sir; and am so well convinced of what you told me, that nothing farther need be said on the subject. TUTOR. As that is the case, I shall proceed.—I dare say you do not forget what the plane of the ecliptic is. PUPIL. I do not, Sir; but have a perfect recollection of it. TUTOR. Now, remember, that the axis of the earth is not upright or perpendicular to the plane of the ecliptic, but inclines to, or leans towards it, 23-1/2 degrees, and makes an angle with it of 66-1/2 degrees. PUPIL. An angle signifies a corner; but that cannot be the meaning here. TUTOR. That is what is generally understood by an angle: but, in geometry, it means the meeting of any two lines which incline to one another, in a certain point. Now, if you conceive the axis of the earth to be one line, and the plane of the ecliptic the other, the point where they meet or cross each other will form an angle. PUPIL. I think I understand it; but how can it contain 23-1/2 or 66-1/2 degrees? TUTOR. You know what a degree is. PUPIL. If I remember right it is the 360th part of a circle. TUTOR. It is so: and the measure of an angle is an arc or part of the circumference of a circle, whose angular point is the center: and so many 360th parts as any arc contains, so many degrees the measure of the angle is said to be; thus, Z C P (Plate III. fig. 1.) makes an angle of 23-1/2 degrees, because the arc Z P contains 23-1/2 360th parts of the whole circle. Then if A B represent the plane of the ecliptic, and N C S the axis of the earth, as D N contains the same number of degrees as Z P, will not its inclination from a perpendicular be 23-1/2 degrees? [Illustration: _Plate III._ _T. Conder Sculp^t._] PUPIL. Nothing can be plainer. TUTOR. For the same reason, as P B contains 66-1/2 parts of the whole circle, the axis of the earth makes an angle of 66-1/2 degrees with the plane of the ecliptic. And, if you add 23-1/2 to 66-1/2 the sum will be 90, which is the measure Z B, or the fourth part of the circle, and makes what is called a right angle, at the point or center C. PUPIL. It is very clear:—but what do the other letters refer to? TUTOR. The extremities of the earth’s axis are called the poles, N the north, and S the south pole, and P the north-pole star, to which, and to the opposite part of the heavens, the axis always points. These extremities in the heavens appear motionless, whilst all other parts seem in a continual state of revolution: the circle of motion appears to increase with the distance from the apparently motionless points to that circle in the heavens which is at an equal distance between them, called the equinoctial, represented by the letters Æ Q; and is the same I promised some time ago to explain to you. PUPIL. I recollect it: and as the line A B represents the plane of the ecliptic, I suppose the line Æ Q is the plane of the equinoctial, which I see crosses it as you then told me. TUTOR. You are right: and it makes an angle with it of 23-1/2 degrees. It is called the equinoctial, because when the sun appears there, that is, in Aries or Libra, the days and nights are equal in all parts of the world, which I shall shew you in due time; and shall now explain to you what I have just mentioned, that the axis of the earth always points to the same parts of the heavens. I am apprehensive you will think it strange that this should be the case, and the axis keep parallel to itself. PUPIL. What am I to understand by the axis being parallel to itself? TUTOR. Two lines are said to be parallel when they do not incline to but keep at equal distances from each other; so that if they were infinitely continued, they would never meet. Now, if you can conceive a line drawn parallel to the earth’s axis in any part of its orbit, it will be parallel to it in every other part of it. A little drawing I have by me, (Plate III. fig 2.) where the earth is represented in four different parts of its orbit, I think will make this plain to you. PUPIL. I comprehend your meaning clearly. But, as the orbit of the earth is 190 millions of miles in diameter, I have not the least conception how it can incline to the same points. Had you not told me to the contrary, I should have thought it must move round them in every revolution of the earth about the sun. TUTOR. That such a motion would be perceptible is evident, if the fixed stars were near the earth; but, compared with their distance, 190 millions of miles is but a mere point: therefore, the axis always inclines to the same points of the heavens. PUPIL. This is a greater proof of the inconceivable distance of the stars than what you mentioned before, and I thought that very astonishing: Wonders on wonders constantly arise, Whene’er we view the earth, or sea, or skies. TUTOR. It is very true. And the more we search, the more we have cause to admire the works of the Almighty. PUPIL. Pray, Sir, what is the next thing you propose? TUTOR. To make you acquainted with the other circles you see in the figure (Plate III. fig. 1.) as it is very necessary you should know them. PUPIL. Will you be kind enough to tell me their names, Sir, and I will endeavour to remember them? TUTOR. That line which divides the globe into two equal parts, called the northern and southern hemispheres, which answers to the equinoctial in the heavens, and is equally distant from the two poles, is called the _equator_; the other which crosses it, as I before told you, is the _ecliptic_; the smaller circle, north of the equator, is the _tropic of Cancer_; that south of it, the _tropic of Capricorn_; the circles next the poles are called the _polar circles_; or that next the north pole, the _arctic circle_, and that next the south pole, the _antarctic circle_; each of which is 23-1/2 degrees distant from its respective pole, as are the tropics from the equator. PUPIL. You have not mentioned the lines which cross the other circles, and terminate in the poles; what are they called? TUTOR. They are called _meridians_, because when any of them, as the earth revolves on its axis, is opposite to the sun, it is mid-day or noon along that line. Twenty-four of these lines are usually drawn on the globe to correspond with the twenty-four hours of the day; but you are not to suppose there are no more than twenty-four; for every place that lies ever so little east or west of another place has a different meridian.—To make this clearer to you, we will suppose the upper 12 (Plate III. fig. 1.) to be opposite the sun, it will of course be noon along that line; the next meridian marked 1, being 15 degrees east, will have passed the meridian 1 hour, consequently it will there be one in the afternoon, and so on, according to the order of the figures, till you come to the lower 12, which being the part of the earth turned directly from the sun, it will be midnight on that meridian; on the next meridian, as you proceed round, it will be one in the morning, the next two, and so on till you arrive at the upper twelve, where you set off. So you see there must be a continual succession of day and night. This difference of time between places lying under different meridians is what is called longitude. PUPIL. I think I have heard of a Mr. Harrison, who made a time-keeper for determining the longitude. Shall I trespass at all if I beg a little farther information on this subject? TUTOR. It is my wish at all times to satisfy your curiosity, when I can do it with propriety. I shall therefore comply with your request.—Mr. Harrison’s time-keeper, and those made since by other artists, are so constructed, that the heat and cold of different climates will not affect them; for, all metals are more or less expanded by heat, and contracted by cold; for which reason it is, that a clock or watch made in the usual way will not keep equal time. Now, all that is required of these time-keepers to ascertain the longitude is this: Suppose a captain of a vessel sailing from London to the West Indies, we will say Kingston, in Jamaica. On his passage thither he makes an observation, and finds the sun on the meridian, or that it is twelve o’clock in that situation, when by his time-keeper it is two in the afternoon in London, whence he concludes he is 30 degrees west of London. PUPIL. I must beg you to explain this to me, as I do not understand why two hours of time should be equal to 30 degrees of longitude. TUTOR. You must consider, that as the earth makes a complete revolution on its axis in 24 hours, it must pass over 360 degrees in that time: now, if you divide 360 by 24, the quotient 15, will be the number of degrees passed over in one hour; 30 degrees will be equal to two hours, &c. The difference of time between London and his situation is two hours, consequently the difference of longitude must be 30 degrees: and, it must be west, because the sun had passed the meridian of London; for, as the earth revolves from west by south to east, one place which lies east of another must come first to the meridian or opposite to the sun. Therefore, when longitude is reckoned from London, if the place lie east of that meridian the time will be before; if west, after London. PUPIL. I see it clearly; and as 60 minutes make an hour, if I divide it by 15, the quotient 4 will be the minutes answering to one degree. TUTOR. You are right: and for the same reason, 4 seconds of time are equal to one minute of longitude, which you know is the 60th part of a degree.—Our captain when arrived at Kingston, finds the difference of time between it and London 5 ho. 6 min. 32 sec. Can you tell me the longitude of Kingston? PUPIL. If I bring the hours and minutes to minutes, and divide by 4, the quotient I think will be degrees, will it not? TUTOR. It will: and the seconds of time divided by 4, will be minutes of longitude. Now try if you can do it. PUPIL. Five hours 6 minutes, multiplied by 60 will be 306 minutes, this divided by 4, will give 76 degrees and 2 over, which 2 is half a degree, or 30 minutes: and 32 seconds of time divided by 4, will be 8 minutes of longitude, the sum of which is 76 degrees 38 minutes for the longitude of Kingston. TUTOR. Very well.—I have just now thought of another method of reducing time to longitude, and longitude to time, which you may probably find easier. However, when you are in possession of both, you may use which you please. PUPIL. That which is easiest must, I think, be best. TUTOR. I will give it you, and let me have your opinion of it. To reduce time to longitude. Multiply the hours, minutes, and seconds of time by 15, or rather by the factors as they are called, namely 3 and 5, carrying one for every 60 in the minutes and seconds, and setting down the remainder, thus: ho. min. sec. 5 6 32 difference of 3 time. ──────────────── 15 19 36 5 ──────────────── Degrees 76 38 0 longitude. ════════════════ Divide the degrees and minutes of longitude by 5 and 3 and the quotient will be the difference of time. PUPIL. I give this the preference. TUTOR. As longitude is seldom mentioned without being accompanied with latitude, that you may not be ignorant of its meaning when you meet with it, I shall just tell you that it is the distance of any place from the equator, reckoned in degrees and minutes on the meridian, and is either north or south as the place lies north or south of the equator. The latitude of any place is equal to the elevation of the pole above the horizon. The latitude of the heavenly bodies is reckoned from the ecliptic, and terminates in the arctic and antarctic circles: and their longitude begins at the point Aries. PUPIL. What is the measure of a degree? TUTOR. A degree of latitude is 60 geographical, or 69-1/2 English miles: and a degree of longitude on the equator is equal to it, because the equator as well as the meridians divides the globe into two equal parts. But a degree of longitude decreases as you approach the poles: for at the poles the meridians meet in a point, consequently a degree there can have no dimension. To-morrow I will shew you the cause of the seasons. DIALOGUE X. PUPIL. I think, Sir, when you left me last night you told me our next business would be to explain the nature of the seasons? TUTOR. I did so, and am persuaded you will find no great difficulty in comprehending it.—Cast your eye on the little drawing I gave you, (Plate III. fig. 2.) where the earth is represented as situated at the four quarters of the year, namely, Spring, Summer, Autumn, and Winter.—But before we proceed to an explanation it will be necessary to remark, that, in the little scheme the eye is supposed to be elevated above the plane of the earth’s orbit, and that we see it very obliquely. The orbit by this means appears very elliptical; and, the enlightened hemisphere, or that half of the earth which is turned to the sun in the spring, and the darkened hemisphere, or that turned from him in the autumn, are there represented. PUPIL. This I understand. TUTOR. Well then, we will begin with the spring.—In this situation of the earth the equator is exactly opposed to the sun: and, as he always enlightens a hemisphere, or half of its surface, his rays will reach to both the poles: whence, from the diurnal revolution of the earth, the day and night are equal all over the globe. PUPIL. This I remember you told me happened when the sun was in Aries and Libra. The sun is now entering Aries: and, as we are in the rays of the sun one half of the diurnal revolution, and in the shadow of the earth, or dark, the other half, the day and night must be equal. TUTOR. Certainly. And as the sun enters Aries in the equinoctial, it is then called the _Vernal_, that is, _Spring Equinox_. When the sun enters the opposite sign Libra, the same effects are produced, and it is then called the _Autumnal Equinox_. PUPIL. You have passed on from Spring to Autumn. TUTOR. I have so.—We will now return, and trace the earth in its orbit from spring to summer.—You have already seen that the north and south poles are both enlightened, and that the day and night are equal at the equinoxes. If the axis of the earth were perpendicular to the plane of the earth’s orbit, this would constantly be the case, and we should have no diversity of seasons: for, the sun being over the equator, the poles must be perpetually enlightened, and of course we should have equal day and night at all times of the year. PUPIL. That is plain. I suppose then that it is to the inclination of the earth’s axis we are indebted for the increase and decrease of days. TUTOR. It is occasioned by the inclination of the earth’s axis and its preserving its parallelism, which I explained to you last evening.—As the sun is now in the first point of Aries, the earth you know must be in the beginning of Libra, it being the opposite sign.—Now fix your attention on the scheme, and imagine the earth to be advancing in its orbit through Libra, Scorpio, and Sagittarius: and at the first degree of Capricorn give me your opinion of the earth’s position. PUPIL. The north pole is turned to the sun, the south pole from him, and the tropic of Cancer is opposite to him. TUTOR. How many degrees are the tropics from the equator, or, in other words, what is the inclination of the earth’s axis? PUPIL. Twenty-three degrees and a half. TUTOR. And so far are the rays of the sun cast beyond the north pole, and fall short of the south pole: so that the whole of the arctic circle is enlightened, and the antarctic circle involved in darkness. PUPIL. What conclusion am I to draw from this? TUTOR. That in the northern half of the globe it is the longest day, or summer, and in the southern half the shortest, or winter, whilst under the equator the days and nights are equal. PUPIL. I used to think that when it was winter or summer here it was so in every part of the world. TUTOR. You now find your mistake. For as the earth is making its progress from Libra, the north pole is approaching the sun, and the south pole receding from him: consequently the length of the day is increasing in the northern hemisphere and decreasing in the southern.—The sun has now been three months above the horizon of the north pole, and the same time below that of the south pole, and in three months more, when the earth arrives at Aries, the scene will be reversed: the sun will be over the equator, both poles will be again enlightened, and the day and night will be equal in every part of the globe. The sun will now be rising to the south and setting to the north pole. This is our Autumn. PUPIL. And as the earth is advancing towards winter, the south pole will be turning to the sun, and the north pole from him, whence I conclude that when the earth is in Cancer it must be summer, south of the equator, when it is our winter. TUTOR. Most assuredly. For you see that the sun is over the tropic of Capricorn, which you know is as much south of the equator as the tropic of Cancer is north of it, where the sun was in our summer. The antarctic circle is now enlightened, and the arctic obscured in shade; but, under the equator there is neither increase nor decrease, the days and nights being each twelve hours. PUPIL. It is now our winter, the sun has been three months above the horizon of the south pole, and will continue so till the vernal equinox, when he will again rise to the north pole, and so on in regular succession. TUTOR. It must be plain then to you that there can be but one day and one night at each of the poles, reckoning the time the sun is above or below their respective horizons; under the arctic and antarctic circles, the longest day is twenty-four hours, and in the shortest the sun is just visible in the horizon at noon. The longest day decreases in length the nearer we approach the equator, where I before observed there is no variation, because the circle bounding light and darkness, in every position of the earth, divides the equator into two equal parts; and, it must be observed, that the longest day and longest night are equal to each other in every part of the globe. PUPIL. If the longest day under the arctic circle be just twenty-four hours, the sun must rise in the north. TUTOR. He does so, makes a complete circle and sets in the [15]north again. From the arctic circle to the equator, he rises north of the east and sets north of the west: at the equator he rises due east and sets due west, thence southward to the antarctic circle, he rises south of the east, and sets south of the west: and under the antarctic circle, as I observed just now, he is visible in the horizon in the south at noon. [Footnote 15: Here it must be observed that there will be a little variation from sun-rising to sun-setting, as the earth is advancing in its orbit.] PUPIL. We usually say, the sun rises in the east and sets in the west. TUTOR. At the equinoxes it must be so in all parts of the globe, the poles excepted: in every other situation, except under the equator, there is a continual change. What I have now told you, respecting the northern hemisphere, will be reversed at our shortest day: that is, in the northern hemisphere the sun will rise south of the east and set south of the west; and, in the southern hemisphere the contrary, the sun will be in the horizon, at noon, under the arctic circle, and the day will be twenty-four hours under the antarctic circle. PUPIL. Pray Sir, are the regions within the polar circles inhabited? If they are, their situation, in winter, must, I think, be dreadful. TUTOR. It is foreign to my present purpose to speak of the inhabitants of the earth, as that more properly belongs to Geography. Thus much however I shall tell you, that, although it must be very cold and dreary, they are not so long deprived of light as you may imagine; for, even under the poles, when the sun is hidden from them, they are but a short time in total darkness, for, you must recollect, that the twilight continues till the sun is eighteen degrees below the horizon; and the sun’s greatest depression, you know, can be but twenty three degrees and a half, equal to the inclination of the earth’s axis. Besides this, the moon is above the horizon of the poles a fortnight together; being half her period north, and the other half south, of the equator; and, as the moon at full is in the sign opposite to the sun, the tropical full moons must be twenty-four hours above the horizon at the polar circles. PUPIL. This description is very pleasing, as I had no idea of their being favoured with so much light in the absence of the sun: and, I find, as the sun is longer above the horizon in summer than in winter, the moon, on the contrary, continues longer with us in winter, when we most need her assistance, than she does in summer. TUTOR. As you seem to understand what I have been explaining, I shall shew you, that the reason why it is hottest when we are farthest from the sun is, that in winter when we are nearest to him the days are shorter, his rays sail very obliquely on us, and are more dispersed than they are in summer, when he not only remains longer above the horizon, but being higher, his rays fall more direct on us, by which means the earth becomes so much heated that it has not time in the short nights to get cold again.—When the earth is nearest the sun it is summer in the southern hemisphere, therefore it is reasonable to suppose that the heat there must far exceed ours in the same latitude; but to counteract this their summer is shorter by eight days than ours: and it is well known that it is much colder near the poles in the southern than in the northern hemisphere: but this is accounted for from there being more land to retain the heat in the latter than in the former. PUPIL. My doubts on this head being now removed, I must beg you to give me such other information as you may think proper. TUTOR. As there are different degrees of heat and cold, the earth has been divided into five zones, namely, one torrid, two temperate, and two frigid zones. PUPIL. How are they distinguished? TUTOR. The torrid zone is all that space surrounding the globe contained between the tropics, having the equator running through the middle of it. It is so called on account of its excessive heat, for, twice every year the sun is vertical to the inhabitants, that is, he shines directly on their heads, and casts no shadow, but under their feet, at noon. PUPIL. We find it sometimes extremely hot here in our summer; surely, in the torrid zone it must be almost insupportable? TUTOR. They are inured to it from their infancy.—But we are departing from our subject.—The temperate zones are comprehended between the tropics and polar circles, that between the tropic of Cancer and the arctic circle is called the north temperate zone, and that between the tropic of Capricorn and the antarctic circle the south temperate zone. PUPIL. I suppose they are called temperate because the heat is not so intense as in the torrid zone? TUTOR. True. Neither is the cold so severe as in the frigid zones, which are those regions comprized within the polar circles, and are denominated north and south, as they are contiguous to the north or south poles. PUPIL. Why are they called frigid? TUTOR. They are called frigid or frozen zones, because near the poles there are perpetual fields of ice, the heat of the sun, even in summer, being insufficient to dissolve it.—Now try if you can tell me the breadth of each zone in degrees. PUPIL. The torrid zone being twenty-three degrees and a half on each side the equator must be forty-seven degrees, which must also be the breadth of the frigid zones, as the polar circles are distant twenty-three degrees and a half from the poles, which are their centers. And, as from the equator to either pole is ninety degrees, from the equator to the tropics twenty-three and a half, and from the polar circle to the pole twenty-three and a half, if the sum of these, that is, forty-seven, be taken from ninety, the remainder, forty-three, will be the breadth of each of the temperate zones. TUTOR. Very well. PUPIL. From what you have told me I have no doubt but that the earth is globular, but I have no proof of it: I must therefore beg your assistance. TUTOR. That it cannot be an extended plane, as some have imagined, is very evident; for, if it were, the angle made with that plane and the north pole star would be always equal, for reasons I have before given you: neither can it be cylindrical, that is like a garden roller, as others have supposed.—If a person travel northward the pole star becomes more elevated, and if he could penetrate to the north pole of the earth the star would be in the zenith, or directly over his head: on the contrary, if he travel southward, it is more and more depressed till he arrives at the equator, where the star is in the horizon; as he proceeds it disappears, and other stars rise to his view, invisible to us. Here then you see it must be circular northward and southward. PUPIL. I am convinced it must be so. TUTOR. And it is as certain that it is so east and west: for, navigators have often sailed round it steering the same course: that is, if they sail an easterly or westerly course at setting off, by continuing the same course they will return to the port whence they departed. This you know they could not do if it were not round, any more than an insect could, by crossing a round table, arrive at the place it set out from; but, by going round the edge it would be still going forward and come again to the point it had left. PUPIL. It is very evident. TUTOR. Again. In every direction, if a ship be seen at a distance, the first things observed are the top-mast and rigging, whilst the hull or body of the ship is hidden behind the convexity, that is roundness of the water, just as you would see a man coming over a hill, you would first see his head, he would be rising more and more to your view till he arrived at the top, where he would be full in sight. PUPIL. I am at a loss to account for the convexity of the water. How can its surface be round? TUTOR. Have you never observed the drops of water falling from the eaves of a house? PUPIL. Often, Sir. TUTOR. Of what shape were they? PUPIL. Globular.—But what is the cause of their being so? TUTOR. Attraction.—For as every particle of water which composes the drop tends to the same center, every part of the surface must be equidistant from the center, it must therefore be spherical. In like manner if you separate quicksilver, each portion will form itself into a globe. PUPIL. All this is very clear. And, for the same reason, the water in the ocean must be convex; for, I remember you told me that it gravitated towards the center of the earth. TUTOR. Once more.—I think you must have seen an eclipse of the moon. PUPIL. I have, Sir. TUTOR. Of what figure was the darkened part? PUPIL. Circular. TUTOR. Take this ball, and hold it before the candle between your finger and thumb, so that the shadow may be thrown on the wall, and in all positions you will find it circular. PUPIL. It is so. TUTOR. Apply this crown piece in the same manner, with the flat side to the candle. PUPIL. It is a circle. TUTOR. Turn it a little obliquely. PUPIL. It is now an ellipsis. TUTOR. Now turn the edge to the candle. PUPIL. The shadow is a strait line. TUTOR. You now see that no other body than that of a globe can in all positions cast a circular shadow. PUPIL. I do, Sir. TUTOR. The darkness on the disc of the moon at the time of an eclipse is the shadow of the earth, which in all situations is circular; the earth, therefore, which casts the shadow, must be a globe. PUPIL. It must be so.—But—— TUTOR. The earth is mountainous.—It is so: but remember that the highest mountain bears no greater proportion to the bulk of the earth than the small irregularities on the peel of an orange bears to that fruit: that objection therefore is soon removed. And yet it is not a true sphere. PUPIL. What then? TUTOR. A spheroid, that is, it is a little flattened at the poles, and is in shape not unlike an orange or a turnip. This you will not be surprized at when I tell you that the equatorial parts are about four thousand miles from the center of motion. PUPIL. I suppose then you infer that as the centrifugal force is greater the farther it is removed from the center, that the parts near the poles have a tendency to fly off towards the equator. TUTOR. I do. And as we have finished this part of our subject, I shall take leave of you. DIALOGUE XI. TUTOR. I now propose giving you a description of the moon, and I doubt not it will afford you some degree of pleasure. PUPIL. Indeed it will, as I know little more than that she is a secondary planet or satellite, revolving round the earth, and with it round the sun. TUTOR. You know her mean distance from the earth. PUPIL. I did not recollect that: 240 thousand miles. TUTOR. Right. Her diameter is about 2161 miles, and her bulk about a fiftieth part of the earth’s. Her axis is almost perpendicular to the plane of the ecliptic, consequently she can have no diversity of seasons. PUPIL. What is her period? TUTOR. The time she takes to revolve from one point of the heavens to the same again is called her _siderial_ or _periodical revolution_, and is performed in 27 days, 7 hours, 43 minutes; but _synodical revolution_, or the time taken up to revolve from the sun to the same apparent situation with respect to the sun again, or from change to change, is 29 days, 12 hours, and 44 minutes. PUPIL. I do not clearly comprehend it. TUTOR. If the earth had no annual motion, the period of the moon would be uniformly 27 days, 7 hours, 43 minutes; but you are to consider that whilst the moon is revolving round the earth, the earth is advancing in its orbit, and of course she must be so much longer in completing her synodical revolution as the difference of time between that and her siderial revolution. This I will make clear to you in a few minutes.—What is the situation of the hour-hand and minute-hand of a watch at twelve o’clock? PUPIL. They will be in conjunction. TUTOR. And will they be in conjunction at one? PUPIL. No, Sir. TUTOR. Yet the minute-hand has made a complete revolution: but before they can be in conjunction again the minute-hand must move forward till it overtakes the hour-hand. PUPIL. I now understand it, and must beg you to explain to me the different phases of the moon. TUTOR. Take this ivory ball, and suspend it by the string with your hand between your eye and the candle. Let the candle represent the sun, the ball the moon, and your head the earth. In this situation, as the candle enlightens only one half of the ball, the part turned from you will be enlightened, and the part turned to you will be dark. This will be a representation of the moon at change, and as no part of her enlightened hemisphere is turned to the earth, she can reflect no light upon it, and consequently is invisible to us. She now rises and sets nearly with the sun.—Turn yourself a little to the left, and you will observe a streak of light like what is called the new moon. PUPIL. I see it clearly. TUTOR. Move round one quarter. PUPIL. One half of the side next me is now enlightened. TUTOR. You may conceive it to be the moon at first quarter.—Go on, and you will see the light increase till the ball is opposite to the candle, when the side next you will be wholly illumined, and will give you a just idea of the moon at full, which now rises about the time of sun-setting, being opposite to the sun: and, the farther she advances in her orbit the later she rises. PUPIL. It is plain it must be so. She rises with the sun at change, being then in conjunction: and as she revolves in her orbit the same way as the earth does on its axis, the earth will have farther to revolve each day before it can see the moon. At the full she is in opposition, and of course rises when the sun sets: and so continues to rise later and later, till the change again. TUTOR. You imagine that the moon rises exactly with the sun when she is at change; and when he sets, at full. I will presently convince you of your mistake; and would have you now proceed with your ball. Place it again opposite to the candle, and as you turn round you will find the light gradually decrease as it before increased, that the side that was before enlightened is now dark, and the dark side light. When you have gone three quarters round, one half of the side next you will be enlightened, and will resemble the moon at last quarter. As you go on the darkened part will increase, till you arrive at the place you set off from, where the light is quite obscured. PUPIL. I have now completed the circuit, and am much delighted with it, as by this simple contrivance I can perceive the various changes of the moon, and that the western side is enlightened from the change to the full, and the eastern side from the full to the change. TUTOR. I find then it has fully answered the purpose intended. PUPIL. Indeed it has. But if you will give me leave I will use the ball again. TUTOR. By all means. PUPIL. I perceive, as I move round, that the same side of the ball is turned towards me whilst every part is turned to the candle. Is it so with the moon? TUTOR. It is: and as every part of the moon is turned to the sun, she makes one revolution on her axis whilst she makes one in her orbit. PUPIL. This is very singular. If the same side of the moon be always turned to the earth, the opposite side of course can never see it. TUTOR. And they must likewise be deprived of the earth as a moon. PUPIL. True. But how is it known that the same side of the moon is always opposed to the earth? TUTOR. The moon, like our earth, consists of mountains and valleys, which, when seen through a good telescope, are very beautiful. The mountainous parts appear as lucid spots and bright streaks of light: and as the same spots, &c. are constantly turned to the earth, she must keep the same side to the earth. PUPIL. It is very clear. Are there no seas? TUTOR. It was formerly imagined that the dark parts were seas, but later observations prove that they are hollow places or caverns, which do not reflect the light of the sun. Besides, if there were seas there would consequently be exhalations, and if exhalations, clouds and vapours, and an atmosphere to support them. That there are no clouds is evident, because when our atmosphere is clear, and the moon above our horizon in the night-time, all her parts appear constantly with the same clear, serene, and calm aspect. PUPIL. Has the moon then no atmosphere? TUTOR. If she has it is imperceptible to us: for, when she approaches any star, we cannot discover with our best telescopes any change of colour or diminution of lustre in the star till the instant it is lost behind her: whence it is clear, that she can have no such gross medium as our atmosphere to surround her. PUPIL. May we not then doubt whether she be inhabited or not, as without air we cannot breathe? TUTOR. The same Almighty Being who created us and gave us air to breathe, may have provided a different way for their existence. It does not hold good that, because we could not live there, she is not inhabited. Fish will live a considerable time in water under an exhausted receiver: and, I have heard of a toad being found in a block of marble. Your doubt therefore, I think, ought not to be admitted. PUPIL. I am satisfied. And must now beg to be informed how I may observe the moon’s motion. TUTOR. Her real motion round the earth, may be easily known by remarking when she is near any particular star. Thus, suppose you see her west, that is to the right of it, she will be approaching, then in conjunction with, and afterwards pass it towards the east. Her apparent motion is that of rising and setting, which is occasioned by the rotation of the earth on its axis. PUPIL. I remember not long since, when you shewed me Jupiter, that the moon was west of him: the next evening I saw her almost appear to touch him, and soon after at a great distance from him easterly. I now see that her real motion is from west by south to east, and her apparent motion from east by south to west. TUTOR. If you have no objection, I will now explain the cause of eclipses. PUPIL. So far from it, that it will give me the greatest pleasure. TUTOR. Take your ivory ball, suspend it as before, in a right line between your eye and the candle.—Can you see the candle? PUPIL. No, Sir. TUTOR. For what reason. PUPIL. Because the ball prevents the light coming to me. TUTOR. This then represents an eclipse of the sun, which can never happen but when the moon is between the sun and the earth, which must be at the change: for, as light passes in a right line, the sun is hidden to that part of the earth which is under the moon, and therefore he must be eclipsed. If the whole of the sun be obscured by the body of the moon, the eclipse is total: if only a part be darkened, it is a partial eclipse; and so many twelfth parts of the sun’s diameter, as the moon covers, so many digits are said to be eclipsed. PUPIL. May not the word digit be applied to the moon as well as the sun? TUTOR. It may: for it means a twelfth part of the diameter of either the sun, or the moon. PUPIL. As you have now shewn me the cause of an eclipse of the sun, I am anxious to have that of the moon explained. TUTOR. We must again have recourse to your little ball.—Turn yourself round till it is opposite to the candle in a line with your head, and you will see that no light can be thrown on it from the candle, because your head is between them. In like manner the rays of the sun are prevented falling on the moon, by the interposition of the earth: she must therefore be eclipsed. PUPIL. I see it clearly. And as an eclipse of the sun happens when the moon is at change, that of the moon must be when she is at full; for, it is then only the earth’s shadow can fall on the moon, the earth being at no other time between the sun and her. TUTOR. The diameter of the shadow is about three times that of the moon, and consequently the moon must be totally eclipsed whilst she continues in it. On the contrary, the shadow of the moon at an eclipse of the sun, covers so small a part of the earth’s surface, that the sun is totally or centrally eclipsed to but a small part of it; and its duration is very short. But a faint or partial shadow surrounds this darkened shade, in which the sun is more or less eclipsed, as the place is nearer to or farther from its center; this partial shadow is called the _penumbra_. I have prepared for you a little drawing, representing an eclipse both of the sun and moon, which I think will enable you better to understand what I have been explaining. (Plate IV. Fig. 1 and 2.) In the former, _p. p._ is the penumbra. [Illustration: _Plate IV._ _T. Conder Sculp^t._] PUPIL. In what does a central differ from a total eclipse? TUTOR. An eclipse of the sun may be central, and not total; for, those who are under the point of the dark shadow, will see the edge of the sun like a fine luminous ring, all around the dark body of the moon when the sun is eclipsed at the moon’s greatest distance from the earth; but when she is nearest the earth at an eclipse of the sun, the eclipse is total. When the penumbra first touches the earth, the general eclipse begins; when it leaves the earth, the general eclipse ends. An eclipse of the moon always begins on the moon’s eastern side, and goes off on her western side; but an eclipse of the sun begins on the sun’s western side, and goes off on his eastern side. When the moon is eclipsed in either of her nodes, the eclipse is both central and total. PUPIL. Pray, what is the reason we have not an eclipse at every full and change of the moon? TUTOR. For the same reason that Mercury and Venus are not seen to pass over she sun’s disc at every inferior conjunction. PUPIL. Is the orbit of the moon then inclined to the plane of the ecliptic? TUTOR. It is: and no eclipse of the sun can happen but when the moon is within 17 degrees of either of her nodes: neither can there be one of the moon, unless she be within 12 degrees. At all other new moons she passeth either above or below the sun, as seen from the earth: and at all other full moons above or below the earth’s shadow, according as she is north or south of the ecliptic. You now see that the moon must sometimes rise before and sometimes after the sun at change, and before or after he sets at full. PUPIL. I do, Sir, and am much obliged to you for this pleasing account of the moon, and of eclipses: and if you have any thing farther to observe, it will afford me additional pleasure. TUTOR. You may, at some time or other, have an opportunity of seeing a total eclipse of the moon; it will therefore be necessary to prepare you for a phænomenon which otherwise you might be much surprized at, and that is, that after the moon is immersed in the earth’s shadow, she is still visible. PUPIL. This is a phænomenon that I am not able to account for; for, the moon being an opaque body, she cannot shine by her own light[16], and the rays of the sun are prevented falling on her by the interposition of the earth, she cannot therefore shine by reflection. [Footnote 16: Dr. Herschell supposes the moon and the rest of the planets may have some inherent light: the side of the planet Venus, turned from the sun, having been seen, as we see the moon soon after the change.] TUTOR. It is by reflection that we see her; for the rays of the sun which fall upon our atmosphere are refracted or bent into the earth’s shadow, and so falling upon the moon are reflected back to us. If we had no atmosphere, she would be totally dark, and of course invisible to us. PUPIL. What is her appearance? TUTOR. It is that of a dusky colour, somewhat like tarnished copper.—I have one thing more to remark before we quit this subject, which is, that the moon’s nodes have a retrograde or backward motion, in a direction contrary to the earth’s annual motion, and go through all the signs and degrees of the ecliptic in little less than nineteen years, when there will be a regular period of eclipses, or return of the same eclipses for many ages. PUPIL. Pray, Sir, what do you propose for our next subject? TUTOR. The ebbing and flowing of the sea, or cause of the tides. DIALOGUE XII. TUTOR. In order to explain the cause of the tides, I have since I saw you last prepared a little drawing for you, (Plate IV. fig. 3.) where S represents the sun, M the moon at change, E the center of the earth, and A B C D its surface, covered with water. It is obvious, from the principles of gravitation, that if the earth were at rest the water in the ocean would be truly spherical, if its figure were not altered by the action of some other power. But, daily experience proves that it is continually agitated. PUPIL. What is the cause of this agitation? TUTOR. The attraction of the sun and moon, particularly the latter: for, as she is so much nearer the earth than the sun, she attracts with a much greater force than he does, and consequently raises the water much higher, which, being a fluid, loses as it were its gravitating power, and yields to their superior force. PUPIL. What proportion does the attractive power of the sun bear to that of the moon? TUTOR. As three to ten. So when the moon is at change, the sun and moon being in conjunction, or on the same side of the earth, the action of both bodies is on the surface of the water, the moon raising it ten parts,[17] and the sun three, the sum of which is thirteen parts, represented by B _b_. Now it is evident, that if thirteen parts be added by the attractive power of those bodies, the same number of parts must be drawn off from some other part, as A _a_, C _c_. It will now be high-water under the moon at _b_, and its opposite side _d_, and low-water at _a_ and _c_. [Footnote 17: By part here I do not mean any specific measure.] PUPIL. That the attraction of the sun and moon must occasion a swelling of the waters on the side next them, I can readily conceive, and that this swell must cause a falling off at the sides: but that the tide should rise as high on the side opposite to the sun and moon, in a direction contrary to their attraction, is what I am not able to account for. TUTOR. This difficulty will be removed when you consider that all bodies moving in circles have a constant tendency to fly off from their centers. Now, as the earth and moon move round their center of gravity, that part of the earth which is at any time opposite to the moon will have a greater centrifugal force than the side next her, and at the earth’s center the centrifugal force exactly balances the attractive force: therefore, as much water is thrown off by the centrifugal force on the side opposite to the moon, as is raised on the side next her by her attraction. Hence, it is plain, that at D, fig. 3, the centrifugal force must be greater than at the center E, and at E than B, because the part D is farther from the center of motion than the part B. On the contrary, the part B being nearer the moon than the center E, the attracting power must there be strongest, and weakest at D. And, as the two opposing powers balance each other at the earth’s center, the tides will rise as high on that side from the moon, by the excess of the centrifugal force, as they rise on the side next her by the excess of her attraction. PUPIL. In this explanation you have mentioned nothing of the sun. TUTOR. From what I have already said it must be plain to you that if there were no moon the sun by his attraction would raise a small tide on the side next him; and, it is as evident that the tides opposite would be raised as high by the centrifugal force: for the sun and earth, as well as the earth and moon, move round their center of gravity. This may be exemplified by an easy experiment. Take a flexible hoop, suppose of thin brass, tie a string to it and whirl it round your head, and it will assume an elliptical shape; the tightness of the string drawing out the side next to your hand, and the centrifugal force throwing off the other. PUPIL. This I clearly comprehend. TUTOR. I shall now refer you to the next figure, (fig. 4.) where F represents the moon at full: the sun and moon are in opposition, and yet the tide is as high on each side as in the former case. I wish you to shew me the cause. PUPIL. I will use my endeavour to do it, Sir. TUTOR. Then I doubt not you will accomplish it. PUPIL. When the moon is at full, ten parts of water are raised from that side of the earth next her, by her attraction; and, as the side which is next her is opposite to the sun, three parts must be thrown off by his centrifugal force, the sum of which will be thirteen parts next the moon.—From the side opposite to the moon, and under the sun, ten parts are thrown off by her centrifugal force, and three raised by his attraction, making thirteen, the same as before. TUTOR. I could not have done it better. These are called _Spring Tides_. But when the moon is in her quarters, the action of the sun and moon are in opposition to each other; that is, they act in contrary directions (see fig. 5.) The moon of herself would raise the water ten parts under her, and throw off ten parts by her centrifugal force on the opposite side; but, the sun being then in a line with the low-water, his action keeps the tides from falling so low there, and consequently from rising so high under and opposite to her. His power, therefore, on the low-water being three parts, leaves only seven parts for the high water, under and oppose the moon. These are called _Neap Tides_. PUPIL. This is very plain. TUTOR. You would naturally suppose that the tides ought to be highest directly under and opposite to the moon: that is, when the moon is due north and south. But we find, that in open seas, where the water flows freely, the moon is generally past the north and south meridian when it is high-water. For, if the moon’s attraction were to cease when she was past the meridian, the motion of ascent communicated to the water before that time would make it continue to rise for some time after: as the heat of the day is greater at three o’clock in the afternoon than it is at twelve; and it is hotter in July and August than in June, when the sun is highest and the days are longest. PUPIL. These are convincing reasons. And, pray what time after the moon has passed the meridian, is it high-water? TUTOR. If the earth were entirely covered with water, so that the tides might regularly follow the moon, she would always be three hours past the meridian of any given place when the tide was at the highest at that place. But, as the earth is not covered with water, the tides do not always answer to the same distance of the moon from the meridian at the same places, because the regular course of the tides is much interrupted by the different capes and corners of the land running out into the oceans and seas in different directions, and also by their running through shoals and channels. But, at whatever distance the moon is from the meridian on any given day, at any place, when the tide is at its height there, it will be so again the next day, much about the time when the moon is at the like distance from the meridian again. PUPIL. Are not the tides later every day than they were the preceding day? TUTOR. Yes; and the reason is obvious: for, whilst the earth is revolving on its axis in twenty-four hours, the moon will be advancing in her orbit; therefore the earth must turn as much more than round its axis before the same place which was under her can come to the same place again with respect to her, as she has advanced in her orbit during that interval of time, which is 50 minutes. This being divided by 4, gives 12-1/2 minutes; so that it will be 6 hours 12-1/2 minutes from high to low-water, and the same time from low to high-water: or 12 hours 25 minutes from high-water to high-water again. PUPIL. This I understand perfectly well. TUTOR. I have now finished my description of the tides, and having a little time to spare, if you wish to know how to find the proportionate magnitude of the planets with that of the earth, and to calculate their distances from the sun, I will employ it that way. PUPIL. At our first conference I remember you shewed me the proportion that the other planets bear to the earth, with their periods and distances from the sun; but to have it in my power to make the calculations myself, will certainly give me great pleasure. TUTOR. To find what proportion any planet bears to the earth; or, that one globe bears to another, you must observe that, _all spheres or globes are in proportion to one another as the cubes of their diameters_. So that you have nothing more to do than to cube the diameter of each, and divide the greatest by the least number, and the quotient will shew you the proportion that one bears to the other. PUPIL. The operation appears very simple; but, as I do not know what a cube number is, I cannot perform it. TUTOR. You cannot forget what a square number is. PUPIL. The product of any number multiplied into itself is a square number, as 4 is the square of 2. TUTOR. Any square number multiplied by its root, or first power, will be a cube number. Thus 4 multiplied by 2 will be 8, which is the cube of 2; 9 is the square or second power, and 27 the cube or third power of 3, &c. This you will perhaps better understand by A TABLE OF Roots. 1. 2. 3. 4. 5. 6. 7. 8. 9. Squares. 1. 4. 9. 16. 25. 36. 49. 64. 81. Cubes. 1. 8. 27. 64. 125. 216. 343. 512. 729. PUPIL. I do, Sir; and am now prepared for an example. TUTOR. The diameter of the sun is 893552 miles, of the earth 7920 miles; how much does the sun exceed the earth in magnitude? PUPIL. The cube of 893522, the sun’s diameter, is 713371492260872648; and of 7920, the earth’s, 496793088000. And 713371492260872648 divided by 496793088000 is equal to 1435952, and so many times is the bulk of the sun greater than that of the earth. TUTOR. This one example may suffice, as I intend by and by to give you a table of diameters, &c.; you may then calculate the rest at your leisure. PUPIL. I shall now, Sir, be glad to have the other explained. TUTOR. The periods of the planets, or the times they take to complete their revolutions in their orbits, are exactly known; and the mean distance of the earth from the sun has been also ascertained. Here, then, we have the periods of all, and the mean distance of one, to find the distances of the rest; which may be found by attending to the following proportion: As the square of the period of any one planet, Is to the cube of its mean distance from the sun; So is the square of the period of any other planet, To the cube of its mean distance. The cube root of this quotient will be the distance sought. PUPIL. Here again I find myself at a loss, as I have not learnt to extract the cube root. TUTOR. I will give you [18]Doctor Turner’s rule, which I think will answer your purpose. [Footnote 18: Young Geometrician’s Companion.] “First, having set down the given number, or resolvend, make a dot over the unit figure, and so on over every third figure (towards the left hand in whole numbers, but towards the right hand in decimals); and so many dots as there are, so many figures will be in the root. Next, seek the nearest cube to the first period; place its root in the quotient, and its cube set under the first period. Subtract it therefrom; and to the remainder bring down one figure only of the next period, which will be a dividend. Then, square the figure put in the quotient, and multiply it by 3, for a divisor. Seek how often this divisor may be had in the dividend, and set the figure in the quotient, which will be the second place in the root. Now, cube the figures in the root, and subtract it from the two first periods of the resolvend; and to the remainder bring down the first figure of the next period, for a new dividend. Square the figures in the quotient, and multiply it by 3, for a new divisor; then proceed in all respects as before, till the whole is finished.” The following example will, I trust, make it clear to you. EXAMPLE. It is required to find the cube root of 15625. . . 15625 (25 8 ───── 12) 76 15625 ───── ..... ═════ Point every third figure, and the first period will be 15; the nearest cube to which, in the table I gave you just now, you will find to be 8, and its root 2; the 8 you must place under the 15, and the 2 in the quotient: take 8 from 15 and 7 will remain, to which bring down 6, the first figure of the next period, and you have 76 for a dividend. The figure put in the quotient is 2, the square of which is 4, which multiplied by 3 is 12, for a divisor. Now 12 in 76 will be 5 times; cube 25, and you will have 15625, which, subtract from the resolvend, and nothing will remain; which shews that the resolvend is a cube number, and 25 its root. PUPIL. You say 12 in 76 is 5 times; I should have said 6 times. TUTOR. In common division it would be so; but as the cube of 26 would be greater than the resolvend from which you are to subtract it, it can go but 5 times. PUPIL. Now, Sir, I think I have a sufficient knowledge of the rule to solve a problem. TUTOR. The earth’s period is 365 days, and its mean distance from the sun 95 millions of miles; the period of Mercury is 88 days—what is his mean distance? PUPIL. As the distance of the earth is given, I must make the square of 365 the first term, the cube of 95 the second, and the square of 88 the third term of the proportion. TUTOR. Certainly.—Take your slate, or a piece of paper, prepare your numbers, and make your proportion. PUPIL. I find the square of 365 = 133225; of 88 = 7744; and the cube of 95 = 857375. Then 133225 : 857375 :: 7744 to a fourth term. I now multiply the second and third terms together, and divide the product by the first, the quotient 49836 is the cube of the mean distance of Mercury from the sun in millions of miles, and the fourth term sought. TUTOR. So far you are right. Now extract the root. . . 49836 (36 3 36 27 3 36 ─── ── ───── 27) 228 Sq. of 3 = 9 216 46656 Mul. by 3 108 ───── ── ───── 3180 Divisor 27 1296 ═════ ══ 36 ───── 7776 3888 ───── Cube of 36 = 46656 ═════ PUPIL. The root I find to be 36, which is the mean distance of Mercury from the sun, in millions of miles. TUTOR. You now see, that although 27 in 228 will go 8 times, yet here it will go but 6 times; and, as there is a remainder, it shews you that the resolvend is not a cube number. PUPIL. I see it clearly. TUTOR. You now seem perfect in the rule; I shall therefore not trouble you with any more examples, but shall give you the table I promised you. ┌─────────────────────────────────────────────────────────────────────┐ │ TABLE. │ ├──────────┬──────────┬───────────────┬───────────────┬───────────────┤ │ Names │Diameters,│ Magnitude, │ Periods, │ Mean Distance │ │ of the │in English│ compared │ in │ from the Sun, │ │ PLANETS. │ Miles. │with the Earth.│Years and Days.│ in Mil. of │ │ │ │ │ │ Miles. │ ├──────────┼──────────┼───────────────┼───────────────┼───────────────┤ │Sun │ [A]893522│ 1435952 │ —— │ —— │ │ │ │ │ │ │ │Mercury │ 3261│ 1/14 │ 0 —— 88 │ 36 │ │ │ │ │ │ │ │Venus │ 7699│ 5/49 │ 0 —— 224 │ 68 │ │ │ │ │ │ │ │Earth │ 7920│ 1 │ 1 or 365 │ 95 │ │ │ │ │ │ │ │Moon │ 2161│ 1/49 │ —— │ —— │ │ │ │ │ │ │ │Mars │ 5312│ 1/3 │ 1 and 322 │ 145 │ │ │ │ │ │ │ │Jupiter │ 90255│ 1479 │ 11 —— 314 │ 494 │ │ │ │ │ │ │ │Saturn │ 80012│ 1031 │ 29 —— 167 │ 906 │ │ │ │ │ │ │ │Georgian │ 34217│ 82 │ 83 —— 121 │ 1812 │ └──────────┴──────────┴───────────────┴───────────────┴───────────────┘ [Footnote A: The Diameters were taken from Adams’s Lectures, Vol. IV. p. 39.] PUPIL. I shall take the first opportunity of calculating the rest, in which I am certain I shall have great satisfaction. TUTOR. I have now conducted you through the elementary parts of astronomy, have given you a general view of the system of the world, and prepared you to pursue the study with profit and pleasure.—In your future researches, the more accurate you are, the more you will discover of regularity, symmetry, and order in the constitution of the frame of nature. “Hail, Sov’reign Goodness! all-productive Mind! “On all thy works thyself inscrib’d we find; “How various all, how variously endow’d, “How great their number, and each part how good! “How perfect then must the Great Parent shine, ⎫ “Who, with one act of energy divine, ⎬ “Laid the vast plan, and finish’d the design!” ⎭ THE END. Directions to the Bookbinder. Plate I. _to face the_ Title. ———— II. —— _page_ 40. ———— III. —— —— 88. ———— IV. —— —— 131. Transcriber’s note: All instances of ‘disk’ changed to ‘disc’ Errata, instance of ‘disk’ on page 79 added, “—— 79. — 5. ⎭” Page 11, ‘Years’ changed to ‘years,’ “130 years after Christ” Page 20, ‘h e’ changed to ‘the,’ “would have as much the appearance” Page 24, ‘cannon ball’ changed to ‘cannon-ball,’ “the time a cannon-ball would” Page 63, comma changed to full stop after ‘TUTOR,’ “TUTOR. Why?” Page 65, ‘a’ changed to ‘_a_,’ “carry a planet from A to _a_” Page 74, ‘itaxis’ changed to ‘its axis,’ “if the earth revolve on its axis every” Page 78, ‘Mercury’ struck after ‘Sun,’ “Sun, Venus, Mars, and Jupiter are known to revolve on their axes” Page 93, ‘cancer’ changed to ‘Cancer,’ “is the _tropic of cancer_; that” Page 93, ‘capricorn’ changed to ‘Capricorn,’ “the _tropic of capricorn_” Page 115, ‘othes’ changed to ‘other,’ “and other stars rise to his” Page 115, ‘bnt’ changed to ‘but,’ “out from; but, by going round” Page 116, ‘it’s’ changed to ‘its,’ “How can its surface be round” Page 128, full stop inserted after ‘eclipses,’ “explain the cause of eclipses.”	38,939	common-pile/project_gutenberg_filtered	56289	project gutenberg	project_gutenberg-dolma-0010.json.gz:1374	https://www.gutenberg.org/ebooks/56289.txt.utf-8
nIxK3v2CLuX1Qs78	A 12 Teaching Techniques of the Holidays Cookbook	The Technique Lecturing was my main approach to teaching for many years. I got pretty good at it—incorporating videos, personal stories, and activities. But, no matter how good I got, I never got the student engagement that I wanted. I also got tired of always feeling like the sage on the stage. Together, this made me feel like an aging rock band playing to an empty bar of uninspired patrons. Then, a friend told me about team-based learning (TBL). In TBL, the students—not the instructor—are on stage. The process fosters engagement through a series of innovative techniques that are simple, safe, meaningful, and fun. In TBL, students are assigned to teams that they work in across the term, and the course is broken down into modules. Each module follows the same process. “Pre-work” (readings/videos/short lecture recordings) is assigned prior to the start of the module. On the first day of the module, the students (working individually and in teams) are quizzed on the fundamentals from that prework. This is where learners will Try, try, and try again. After that, the rest of the module is taken up by the teams solving and discussing application activities (i.e., meaningful real world problems). This is where the Four S’s come into play. Below, I describe the very basics of TBL. Check out Getting Started with Team-Based Learning (Sibley & Ostafichuk, 2014) for a more in-depth guide to and description of the approach. That’s where everything below comes from. My experience using TBL has not been entirely smooth, but it is helping to create a classroom environment that much more closely reflects my ideal image of post-secondary learning. A bonus is that it fits really well with best practices of online course delivery. How I Use It This term I’m delivering my TBL course synchronously via Zoom (two 90 minute sessions/week). Modules span 4-6 sessions. The process can go over a couple of weeks, as the first session will focus primarily on Try, try, and try again, and the next 2-3 sessions will focus primarily on the Four S’s. 1st session: Try, try, and try again \| The session starts with students individually taking a quiz on the fundamentals of the prework. Quizzes are 15-20 multi-choice questions. \| \| \| I then put students into breakout rooms with their teammates, and they take the exact same quiz as a team. Here, TBL recommends a technique where teams keep on choosing answers to every question until they choose the right one. Try, try, and try again. \| \| \| Once all the teams are done, we all come back to the main room. We discuss questions that teams struggled with or that they had concerns about. Instead of me telling them what the right answer was and why, I encourage teams to share the processes/approaches they used to narrow down the correct answer. Student-centred. \| This process of individual & team quizzes, intra- and inter-team discussion, and Try, try, and try again not only tests but also augments their understanding of the learning. Altogether, it takes about 60-70 minutes. Remaining Sessions: The Four S’s In the rest of the module sessions, the teams solve and discuss application activities. This is where the 4S’s come into play: - Significant Problem: The application activities present problems that are meaningful, intriguing, relevant, and rich. - Same Problem: Every team takes on the same problem at the same time. I use breakout rooms for this. - Specific Choice: Each team solves the problem by choosing a specific answer (e.g. a multiple-choice option) or by producing a specific product. - Simultaneous Report: We then come back to the main room, and the team’s answers are simultaneously presented to the whole class. No team can hide, but there’s no reason to because you’ve got the support of your teammates. I then facilitate a discussion between the teams where they debate the pros and cons of the different answers/products (ideally using the prework as a foundation for their arguments). It’s great when you get a variety of answers because then you can get a rich discussion where different teams argue for different answers with me moderating, guiding, and facilitating the discussion. Depending on its complexity, a single application activity can take anywhere from 20-80m. Then, we move on to the next activity. Feedback from Learners “I enjoyed the opportunity to get to know other classmates through group conversations and class debates. Rarely are students required to analytically think and then express their opinions in class; however, in this class, the course provided students with an environment to learn how to respectfully argue one’s point of view and have it heard by others, which I believe is an essential skill not only in school but also the workplace.” A Short Task to Challenge You Let’s do a quick check on your TBL technique retention. One Final Task Is this something you can use in your classroom? How might you utilize it? If you want to share your results on social media, include a link to this lesson for context.	1,099	common-pile/pressbooks_filtered	https://ecampusontario.pressbooks.pub/12techniquesoftheholidays/chapter/2020-lesson11/	pressbooks	pressbooks-0000.json.gz:21364	https://ecampusontario.pressbooks.pub/12techniquesoftheholidays/chapter/2020-lesson11/
_-3ShBHObaPIod21	6.5: Back Matter	6.5: Back Matter - Describe various sections that may be used in the back matter of a report It may sound like a catch-all to say that all that is left goes in the back matter (also called appendices). To do so appears to devalue the significant importance of material found in this section; however, the back matter can provide critical details that could not easily fit in the body of the report. This section can be used in both informational and analytical reports. In the back matter, there is little prose provided to explain or connect the different items, as the purpose of each item was explained in the body of the report when each item was first referenced. Thus, the back matter is simply the location of these more detailed items that are critical to support the report. There is no “standard” list of items that should be included in the back matter of a report. If the report is a response to an RFI or RFP, there may be extensive costs listed. In other cases, this section may include sample contracts, which can become finalized should the bid be accepted. T here may also be extensive data sets provided, which cover far more detail than the body of the report allows. As mentioned in our discussion of the body of the report, you may also find individuals’ resumes. Simply put, this section can contain anything needed to further support your report; however, resist the temptation to overdo it and include only items that are truly relevant. Contributors and Attributions - Back Matter. Authored by : Susan Kendall. Provided by : Lumen Learning. License : CC BY: Attribution	364	common-pile/libretexts_filtered	https://biz.libretexts.org/Bookshelves/Business/Business_English_and_Communication/Business_Communication_Skills_for_Managers_(Lumen)/06%3A_Reports/6.05%3A_Back_Matter	libretexts	libretexts-0000.json.gz:17345	https://biz.libretexts.org/Bookshelves/Business/Business_English_and_Communication/Business_Communication_Skills_for_Managers_(Lumen)/06%3A_Reports/6.05%3A_Back_Matter
qfqDCfOffR9BgkIr	Principal insects liable to be distributed on nursery stock / by Nathan Banks.	Division of Entomology, Washington, D. C., April 29, 1902. Sir: I have the honor to transmit for publication a manuscript prepared by Mr. Nathan Banks, of this office, in which are considered the principal insects liable to be distributed upon nursery stock. The inspection of nursery stock under State laws has become so general throughout the United States that the desirability of some publication of this sort has become very evident. I had the matter in mind last autumn, and at a conference of the official horticultural inspectors for the United States, held at Washington October 11-13, 1901, a resolution was unanimously passed requesting this Department to prepare and publish an article on those nursery pests of the country which are capable of transmission on nursery stock to the injury of the purchasers. Since it is desirable that this manuscript shall be put in available shape for distribution to all horticultural inspectors and to all nurserymen and others immediately interested, I recommend that it be issued as Bulletin No. 34, new series, of this Division. Respectfully, INTRODUCTION. In preparing this descriptive catalogue of the insects liable to be transported upon nursery stock, it has appeared that there is a great disparity of views as to what insects should be included. To include only such as are known to be very destructive would exclude a great many species that will be found by anyone who examines a tree in the fall or early spring. To include all the species that are known to be found in any stage upon fruit trees in winter would make the list too bulky. Therefore, all species known to be of more than local interest have been treated. Notes on the species infesting fruits are added at the end. The insects have been arranged according to their natural orders, and in the Hemiptera (bugs, scale insects, plant-lice) according to the families. In the Coleoptera (beetles, weevils) and Lepidoptera (butterflies and moths), such an arrangement did not seem desirable. No account of the remedies to be recommended or used is given, as these differ greatly, according to locality and conditions, and the various State laws specify certain treatments. It will be a great help to those interested in the growth and sale of young fruit trees to be able to recognize the appearance of the various insect pests during the winter; therefore, much attention has been paid to this phase of the subject. This tube or beak is composed of several needle-like pieces so shaped and arranged that they inclose a minute channel up which the liquid food is drawn. The beak is inserted in the plant often to some distance beneath the surface. The members of this order do not pass through a pupal or chrysalis stage like the butterflies and moths, but there is an approach to it in the males of the scale insects. The insects of this order to be treated are arranged in four families, which may be separated, for our purposes, as follows: The scale insects, or bark-lice, are readily known from most insects in that the stages commonly seen are immovably fixed to the bark or leaf, and show no outward sign of legs or other structures. For a short time after birth they are active, crawling creatures, and distribute themselves over the surface of the plant. As they grow the protected or covered barklice secrete a waxy substance that hardens and forms the scale. When the insect molts the old skin or exuvium remains attached to the scale. The shape, color, and position of this exuvium is of great value in identifying the specie-. Their small size and similarity of appearance makes their determination difficult, and it is rarely safe to determine the species by a few individuals, but on a moderately infested branch one is apt to find some specimens that are quite characteristic of the species. This insect, formerly known as L.persicae, is (me of the largest of the scale insects, being about one-tifth of an inch long and two thirds as wide. It is elliptical in outline and strongly convex. It is usually of a dull greenish-brown color, sometimes distinctly marked with darker bands. It is found upon the branches of peach and plum, more rarely on apple, and commonty occurs on the under side of the branch, the upper side of which is covered with a black fungus that grows on the honey -dew dropped by the Lecaniums from the branch above. The females pass the winter in the adult condition. The eggs are developed by the latter part of May. The young hatch early in June and continue for fully a month (June 10 to July 15). The young larvae are flat, uniformly pale yellow, and with a thin marginal rim. The}r become stationary in a few weeks. By the middle of July the male pupae are developed, and by the 22d the first winged males appear. There is but one brood a year, and the best time for treatment will' be during July. There is another species of Lecanium (Z. prunastri), less commonly found on plum. The female is much like that of the peach Lecanium, but the insect passes the winter in the larval state, not maturing till May. The young hatch in July, migrate to the leaves, and in the early fall return to the branches, where they pass the winter. It has rarely been found in this country outside of New York State. The oyster-shell bark-louse is one of the best known enemies of the orchardist. It is a dark, slightly convex scale, elongate and usually curved in outline, much resembling a miniature oyster shell. When crowded upon the tree they are apt to be less curved and often quite straight. The elongate exuvium is situated at the small end. Its elongate shape and dark color at once separate it from all other common orchard scales. The eggs, which are whitish in color, are deposited in late summer, and occupy the posterior two-thirds'of the scale. The female dies, but the scale remains to protect the eggs during the winter. The young hatch in Ma}^ or early June, crawl out upon the twigs and small branches, and locate there permanently. In a day or two they begin the formation of the scale. The male scale is much smaller than the female, elongate, wider behind than in front, and little, if any, curved. It is uncommon on apple, but often found on other food plants. The winged male insect appears in midsummer. There is but one brood a year in the North, but in parts of the South there are apparently two broods; the second one hatching about September 1. The oyster-shell bark-louse is widely distributed and attacks a great variety of trees, but is especially partial to apple. This common orchard scale is readily known by its whitish color and ovate form. The adult female scale is rather flat, irregularly ovate in outline, with the yellowish exuvium at the apex. The life history is and three keels or ridges. The winged male insects issue in September. There is but one brood in the North, but probably two or even three in the South. The scurfy bark-louse is widely distributed and occurs on most orchard trees, but chiefly on apple and pear. To this genus belongs the most destructive known species, the San Jose scale. The other species, however, often cause much damage. There is a considerable resemblance among the various species, so that it is difficult for sluj inexperienced person to determine them. The final characters that separate species are based on the structure of the pygidial plate of the adult female scale. To observe this it is necessary that a specimen be boiled in caustic potash and mounted in balsam on a glass slide. When this is examined under a microscope the lobes, spines, hairs, and sinuations of the margin of the plate appear quite distinctly. Thus, the characters that may be used in the field are not final and only comparative, and great care must be exercised, especially when only a small amount of material is available, and any doubt can be settled only by sending the material to some competent authority who can mount and microscopically examine the species. In identifying scale insects by means of the above table, scales should be examined from bark or fruit as clean as possible, and where the scales are not crowded and have room to normally develop. When thickly massed they lose their characteristic shape and appearance, and on sooty or dirty bark they are discolored and abnormal. The San Jose scale is known to every orchardist by hearsay, but few, however, can distinguish it from allied scales, such as ancyhis, y brbesi, and osi/reaefonnis. On badly infested trees the scale presents the appearance of dark gray, scurfy patches. The individual scale is about 2mm in diameter, usually nearly circular in outline, of a grayish color, with the central darker nipple surrounded by one or more quite distinct yellowish or pale grayish rings. When the scales are crowded the outline is more or less distorted. In none of the allied forms is the adult female scale as nearly circular as in the San Jose scale. When on fruit or young twigs there is often a reddish discoloration around the scale. Putnam's scale and the cherry scale have a brighter colored exuvium, situate one side of the center. The cherry scale is often much paler than the San Jose scale. The European fruit scale has an exuvium similar to the San Jose, but lacks the darker nipple; moreover, the exuvium is plainly not at the center of the scale. The male of the San Jose scale is about two times as long as broad; broader at one end than at the other, with a large, dark exuvium, showing a central nipple. It is situated toward the small end of the scale. The male of the European fruit scale is not so elongate, and the exuvium is but little darker than the scale and nearer to the small end than in the San Jose scale. The male of Putnam's scale is as elongate as that of San Jose, but has an orange exuvium. The male of the cherry scale is in shape much like that of the San Jose scale, but the exuvium is of a brighter yellow, the scale usually being paler than the San Jose. In general the adult female of the San Jose scale may be distinguished from its allies by the more circular scale, with yellow exuvium, when exposed, more centrally located, otherwise with dark nipple; the male by similar characteristics of exuvium and nipple. But the San Jose scale is most easily recognized by its immature scales, which are almost black, circular, and with a central nipple surrounded by one or two depressed circular rings. Such a character is not found in any other of the allied scales. The San Jose scale attacks all of our orchard trees, but appears to be most destructive to pear and peach. The insect is represented in winter by partly grown specimens whose development was stopped by the cold weather. They resume growth in the early spring; the males soon appear, mate with the females, and the latter give birth to living young. At Washington, D. C, this time is about the middle of May, and the young continue to appear for about six weeks. The larva crawls off a little way. settles, and within two days begins the secretion of its scale. This young scale is at first white with a swelling in the center. If it is situated on green tissue it is apt to produce a redness. In a few days the pale scale becomes nearly black, with a central nipple surrounded by one or two depressed rings. This form is very characteristic of the species. In about twenty-five days another brood of males appears, and in thirty days the females become adult. At about thirty -five or forty days of age the females begin to give birth to living young. Since one of these mother scales may have been born six weeks before another, it results that there is a This species can usually be readily separated from the San Jose scale by the characters mentioned under that species, but it is practically impossible, without making a microscopic mount, to distinguish it from Putnam's scale and the cherry scale. The cherry scale, especially when on cherry, is more shining and often shows a grayish margin. The European fruit scale occurs on all orchard trees, but only, so far as known, in certain Northern States. The winter is passed by the partly grown specimens, which become mature toward the last of June, and soon begin to give birth to living }^oung. The young continue to appear for several weeks. There appears to be but one brood a year, at least in the Northern States. This scale is widely distributed and attacks all orchard trees. In general appearance it is like the San Jose scale, but at once known by the exposed orange exuvium, the less circular scale, and by the halfgrown young having- no depressed ring around the nipple. It can be separated from the European fruit scale and from the cherry scale only by a microscopic examination of mounted specimens. It is usually much darker than the cherry scale, the exUvium usually a brighter orange, and the scale more conical than that species. Specimens vary, however, a great deal in these points. The insect winters in a nearly fullgrown condition. The males appear in April, soon pair with the females, and the latter deposit eggs in the late spring or early summer. The }roung begin to hatch early in July and continue during the month. There is but one brood a }Tear. This scale is similar to Putnam's and to the European fruit scale, but sometimes, especially on cherry, it is more shining, and presents a gray rim around the scale, which is commonly flatter than the allied species. It attacks all orchard trees, but is rarely common. It winters partly grown, like its allies. The male issues in April. The eggs are laid in April or earl}r May, the young hatching during May and part of June. There appears to be two broods a year, the males of the second brood issuing during the latter part of July and the young during August and September. Fig. 8. — Aspidiotus ostrexformis: a. scales on twig; b, natural size; c, immature stage: <l, female: e, male; /and g, inside of scales. I Marlatt.) This insect is at once recognized by the large size of the adult female scale, it being the largest of our species of the genus, the scale often being 3mm in diameter (one-twelfth inch), while the San Jose scale is scarcel}T 2mm in diameter. The adult female scab4 is irregularly circular in outline, quite flat, and of a pale grayish or dirty- white color. The exuvial spot is reddish or orange and situated one side of the center. The scale often appears to be less closely attached to the bark than with the other species of this genus. The male scale is elliptical and much smaller than the female. The adult female scale hibernates, and deposits eggs in early spring. The males from them issue early in June. Eggs are deposited again in June, so that there appears to be two or possibly three broods in the South. This species is not abundant, but liable to be found on almost any orchard tree. This is quite a large species, readily distinguished from the others we have treated by its very convex scale and uniform drab or yellowish-brown color, except for the dark brown exuvium which often shows near the center. The adult female scale is less circular than most of the other species, and does not always show the exuvial spot, which is at one side and covered with a film of secretion. The male scale is much smaller, and elliptical in outline. The young are nearly circular, with a central nipple often surrounded by a pale gray ring. This scale is ver}^ abundant in California and has spread somewhat eastward, especially in the South. It attacks various orchard trees, but more commonly the orange. It is a scale that is liable to be found more commonly in the future, and orchardists should be on the lookout for it. The greedy scale, in California, winters in all stages. This is a more or less elliptical scale, with the exuvium rather nearer one end. It has a yellowish or pale brownish color, with a whitish center near the exuvium, the latter of a pale yellow. The scales are often found in a longitudinal row, and rarely infest both sides of the same branch. It winters in the ego- stage. The young- hatch in May; the males issue in the summer. There is but one brood a year. It is practically confined to the grape, but has been found on a few other exuvium is often a little way from the margin, and is yellowish or orange in color. Its pale color and elongate exuvium will readily separate it from all other scales on orchard trees. The insect passes the winter with the mature females and the male scales. The males hatch in early spring. The eggs are laid early in May, and the larvae hatch in about ten days. The males again commence to issue by the middle of June, and the females begin egg-laying by the end of June. The second generation is full grown by the middle of August, and these in time soon begin to lay eggs for the brood that will winter as mature females and undeveloped males. The male scale (fig. 11, c, d) is elongate, about three times as long as broad, , slightly wider behind than in front, with a median keel, and snow white in color. The male scales appear to be most numerous on the lower parts of the branches and near the base of the trunk and often so matted as to make the trunk or lower branches absolutely snow white. The peach scale is becoming common in many of the Southern States and as far north as Pennsylvania. It infests plum, cherry, and peach, and less commonly other plants. This species is similar to the peach .scale, and, indeed, the easiest way to distinguish between them is by their host plants. The peach scale does not affect the host plants of the rose scale, which are roses. raspberry, and blackberry. The scale covering is much more thin and delicate and the exuvium is usually of a paler or duller yellow than in the case of the peach scale. The keel or ridge of the male is more distinct. The life history of this species does not appear to be well known in this country. It winters, as a rule, in the eg^ as far north as New Jerse}T; but mature females and immature females and males may be found in winter. In the early spring one often finds the female scales surrounded by a radiate ,flT The plant-lice are small, sluggish insects found on the under surface of leaves or on the bark and roots. W§^ Most of the individuals have no wings, but at times ^ one finds some specimens with delicate transparent % Jj^i wings laid roof -like over the body. They all have ^\| distinct legs, a pair of moderately long antenna?, and usually quite prominent eyes. They occur in colonies, and by their numbers often do a considerable amount of damage. The eggs are found on trees in jgj winter situated near the base of twigs and buds. (See fig. 13.) Thev are minute, oval, or elliptical shining fig. 13.— Eggs of a black objects/ During the warm part of the year the ^^)°ntwig' females produce living young, so that one individual may, in a few months, be the parent of a large colony. Many of the species secrete a sweetish liquid from two pre-apical tubes or cornicles. This liquid is known as honey-dew, and attracts other insects, especially ants. indicate the presence of this insect. This cottony substance is a wax-like excretion clinging to the posterior parts of a small, reddish -brown wingless aphis. It is not, however, this form on the trunks that causes injury. This aerial form is but the indication that there are other specimens, under the ground and feeding on the roots of the tree. It is the latter form that seriously affects the vitality of the tree. Upon the trunk the lice often cause a roughening of the bark, especially on the new growth around scars made by pruning. On the roots the lice cause hard and large knots, which eventually produce a "club-footed" condition of the roots. Such trees usually show their weakness by the fewer and duller colored leaves. Spy, that appear to be immune inonly found on the trunk and roots in summer are the wingless, agamic females. They give birth to living young, and continue to do so, possibly for several years. In spring some of the root-lice4 will crawl up the trunk and continue to breed there till fall. The colonies of lice on the trunk give rise to winged and migratory females. These, when they locate, give birth to wingless male and female lice, and each female deposits a single winter egg in a crevice of the bark. This egg will, in the spring, hatch into a female which will start a new colony of wingless lice on the trunk. Some of these will, in the summer, crawl down upon the roots and continue to breed there. In the north the colonies on the trunk are apt to be killed out by the severe cold weather, but in warmer latitudes many of them live through the winter, particularly if they are protected by a piece of bark. This insect, like the woolly apple aphis, does its great injury underground. Its ravages on the roots of peach give a sickly appearance to the foliage of the affected tree, the leaves often being light green or yellowish in color, and their edges somewhat rolled. The wingless lice on the roots are of a dark-brown color. They breed there continuously without producing males or eggs. Early in the spring some of the root-lice crawl up the trunk of the tree and locate on the young twigs. Here the winged form develops and migrates to other trees to found other colonies. The winged insect is of a shining black or very dark brown color, the tibia? of the legs being mostly yellowish. The foliage of apple trees, particularly of young trees, often appears curled, and sometimes discolored. This curling is produced by colonies of plant-lice. These lice secrete a sticky liquid known as honeydew, which falls on the leaves below. There are several of these plant-lice that attack the leaves of apple; two of them are greenish in color, another has a reddish tinge. The commoner of the two green species is known as Aphis mali Fitch, (probably Aphis annum Oest). Its life history is about as follows: The eggs are laid on the tree in the fall, partly hidden in crevices of the bark; the young hatch from these eggs in early spring, and grow into wingless and sexless lice, known as "stem-mothers," which produce living young; these young become winged, and, in the early summer, migrate to grasses, where they increase during the summer. In the fall they develop a set of winged, sexless lice, which migrate back to the apple and give birth to sexed individuals; these pair, and the female lays her eggs. The other green species is Aphis mali Koch. It passes its entire life history upon the apple. The eggs are laid in the late fall. They are black, and occur generally on the trunk and branches. In early spring the young hatch from these and grow into stem-mothers. These produce living young for a number of generations. Many of these of the first two generations become winged, fly to other apple trees, and there start colonies. In October sexed specimens are produced, and the female lays the eggs that are destined to pass the winter. The other apple plant-louse is A. sorbi Kalt. It is distinctly tinged with red, and the wingless forms have a whitish powdering on the body. This species has a life history similar to that of Aphis mali Fitch., but it is not known what plants serve as its summer hosts. This insect winters in the egg state. The young on hatching in spring go to the under surface of the leaf and there multiply rapidly. Their bodies are covered by a bluish-white mealy powder. Winged specimens are occasionally developed which migrate to other trees. They feed on the plum all summer, but some specimens are said to migrate to grass in early summer. In the fall the winter egg is attached to a plum twig, usually at the base of a bud. At times they do considerable damage to young plum stock. This aphis often causes the leaves of the cherry to become crumpled and rolled, and on young trees sometimes does serious damage. The winged and wingless insects are both of a dark brown color, and look much like the black peach aphis. The c^^ are laid in the fall on the branches at the base of buds and in crevices of the bark. The young hatch from them in the spring when the buds begin to swell. crawl out upon the buds and growing leaves, and develop into stemmothers, which give birth to living young. This is kept up all summer until the fall, when the sexes appear and the female deposits her eggs. A number of winged migrants are developed in the spring generations, which serve to spread the species. The insects usually become very abundant by June, but in midsummer they are not as body. When disturbed, it hops and flies away. The insect is widely distributed in the East, but usually is not abundant enough to seriously injure the ttree. When they become excessively abundant they cause the leaves and fruit to dr}^ and fall. The adult insect hibernates in crevices of the bark. These overwintering specimens are brownish-black in color, with bronzy eyes. The}^ emerge from their hiding places in the early spring, mate, and the female begins to lay eggs before the leaves are out. The eggs are placed singly or in groups in crevices of the bark of the twigs or in old leaf scars, and, when the leaves have unfolded, upon the leaves themselves. They at once commence to excrete hone}r-dew, and when the insects are extremely numerous the amount of liquid secreted is enormous and fairty rains from the tree. A black fungus grows on the honey-infested leaves and tree, so that the whole soon has a smoked appearance. In about thirty days the larva becomes adult. Development continues all through the summer, and there may be as many a live broods if the season be long enough. It is only known to attack the pear. Upon young fruit trees, particularly the apple, one sometimes sees a series of oval or elliptical scars that disfigure and weaken the branches and render them liable to other insect attack. These scars are the results of the work of a curious insect, the buffalo tree-Lopper. It is a grass-green, triangular insect that hops and flies away when disturbed. The pronotum of the thorax is enlarged, as with others of this family, to cover the head and most of the abdomen. The anterior corners of the pronotum project laterally into acute angles. In August and September the adult insects ma}^ be found on the trees engaged in oviposition. The female cuts the bark with her ovipositor in two nearly opposite curved slits, so that the bark between is cut loose. Beneath each slit she deposits a series of from 6 to 12 eggs. These eggs hatch in the spring. The dead piece of bark falls out and leaves the elliptical scar, which enlarges with the subsequent growth of the twigs and becomes an inviting point for the attack of other insects. There is but one brood each year. The caterpillars and cocoons of these insects are known to all. The caterpillars differ from the grubs of beetles in that they have on the under side two rows of pro-legs — fleshy, wart-like structures that serve to support the posterior part of the body. The injuries caused by these insects are made by the caterpillar. These have biting mouthparts that nip out tiny pieces of the leaf or wood, which is then chewed and swallowed. The more injurious forms that are liable to be transported on nursery stock may be arranged as follows: and nursery trees in May and June. The caterpillars use this tent as a common home, where they retire at night and remain during cloudy days. Each clear morning, at about 8 o'clock, they go out along the branches to the leaves for feeding. The amount of damage done will depend a great deal upon the number of tents upon the tree. The eggs are laid in masses of 200 or 300 arranged in a broad belt around the twig. (See fi.g. 19, c.) Each end of this belt tapers off to the twig, which character serves to distinguish it from similar egg-clusters of certain other moths. Each mass is covered with a glistening substance that protects it from the rain. The }^oung caterpillars hatch during the- latter part of April or earty in May, at about the time when the leaves are expanding. They immediately begin to feed on the leaves near by and to unite them into their tent, which is enlarged as the caterpillars grow. The full-grown larva is nearly 2 inches long, hairy and black, with a white stripe along the back. On each side of tree tent caterpillar are often seen among the terminal branches of fruit trees. These are the work of the fall webworm. The eggs of this moth, 300 to 500 in number, are laid in patches on either side of the leaves in June. The larvae issue from June to August, and at once begin their web. They eat only the upper surface of the leaf, leaving the veins and the under surface untouched. The young caterpillar is pale yellowish, with dark spots along the sides and covered with scattered hairs. The full-grown caterpillar is velvety black above, the sides have two yellow stripes, and between them are many blackish patches and dots. The yellowish or brownish hairs are mostly in tufts which arise from tubercles or warts. Some specimens are quite pale; others very dark. In September or October the caterpillar is ready to pupate, and descends to the main branches or trunk of the tree. Here it makes a delicate cocoon, within which it changes to a chrysalis. The insect passes the winter in this stage, and the moth emerges the following spring. The latter has white, sometimes spotted wings, and expands about an inch and a half. There is but one brood each year in the North, but from New York city south there are two broods, the caterpillars of the second making their appearance in August. should be able to recognize it. During winter their small but very compact webs or nests attached to the terminal twigs are very prominent objects and will aid in distinguishing the species. In midsummer the eggs may be found in patches of two or three hundred attached to the under side of a leaf near the tip of a branch. The o^ mass is covered by a dense Uryer of brown hairs from the tip of the abdomen of the female. The young hatch in August and eat the surface of the leaf. As soon as it is devoured thev draw another leaf to it, until in the fall the}^ have quite a tent. On the approach of winter they strengthen their tent and use it to shelter them during the winter. In spring they come out, eat the unfolding buds and tender leaves, and thus do great damage. The full-grown caterpillar is about 1^ inches long, dark brown, mottled, and spotted with orange, and clothed with reddish-brown hairs and two rows of dense tufts of white hair along the upper side of the body. By the middle of June the caterpillars are ready to pupate, and each makes a cocoon attached to a terminal branch, or sometimes elsewhere on the tree, or even on some other object. These cocoons are often close to each other, so as to form quite a mass. The moths emerge in a few weeks. They have white wings, and the females a brown tip to the abdomen. There is but one brood each year. The presence of this insect is easily recognized in winter by the clusters of brown, shriveled, and partly eaten leaves fastened together and to the twigs by silken threads. Within each cluster of leaves is a curved tube, usually sinuate at the small end, and within this tube is the small, brownish caterpillar of this moth. This caterpillar is but half grown. In early spring the larva cuts loose from its fastenings, crawls with its case out upon the branches, and attacks the developing buds and young leaves, thus causing a great deal of injury. The caterpillar becomes full fed by the middle of May, and is then of a greenish color. It pupates in the larval nest, and the moths issue in June or early July. The eggs are deposited in July, singly on the leaves. The young larva, upon hatching, starts to make a little case for itself, which it enlarges when necessary. They feed on all fruit trees, but are partial to apple, and there. is but one brood annually. The caterpillar of this moth, which does great damage to shade trees in cities, sometimes attacks apple and other fruit trees. The adult insect is a light-grayish moth, the female wingless, the male with ashgray wings, expanding about li inches, and the antennae are feathered. The eggs, 300 to 500 in number, are laid by the wingless female in the fall within a frothy substance, which on drying becomes hard and brittle. The whole is a very prominent whitish mass, often situated partry or wholly upon the old cocoon. In Ma}^ the }roung larvae hatch and begin eating the foliage. The larvae are full-grown in July, and spin their slight silken cocoons, attached to any convenient spot. The full-grown caterpillar is a very handsome insect, about li inches in The eggs to the number of 400 to 500 are deposited in clusters attached to trees, fences, etc. Each cluster is covered with yellow hairs from the body of the female, which causes the mass to resemble a piece of sponge. The caterpillars hatch from April to June, and feed voraciously on the leaves, mostl}T at night. The full-grown caterpillar is about 2 inches long, of a grayish, mottled appearance, with the tuber- cles on the anterior part of the bod}^ blue, and those on the hinder part of the body red, all giving rise to long yellow and black hairs. When the caterpillars are about half grown they begin to crawl down the tree to the ground in early morning, and ascend again for feeding in the evening. B37 July they are ready to pupate in a thin cocoon fastened to the trunk of the tree, to a fence, or other convenient object. The pupal period is about ten days, and the moths issue in August. The female moth has whitish wings with several black spots, notably around the outer margin. The male is brownish, with darker undulate lines and spots. The gipsy moth attacks almost every sort of tree, and there is but one brood a year. These .slender, bare caterpillars appear on apple and other fruit trees in early spring and eat holes in the leaves. As they crawl they loop up the body, and are thus called "measuring worms" or "inch worms." There are two species of the cankerworms, their habits, how- v. pupa. ever, being similar. The eggs are laid in clusters on the tree in the fall and early winter, with the fall species {AlsojphUa pometaria Harr.); in March or April with the spring species (Paleacrita vemata Peck). The eggs of the former are flattened on top; those of the latter are rounded. The larva1 hatch in early spring and at once feed on the leaves. When full grown they descend to the ground and pupate therein, the moths issuing in late fall or wry early spring. The females are wingless, and obliged to crawl up the tree to deposit eggs. The males have large, thin, gray wings. There is but one brood each year. This destructive insect is readily discerned by the presence of a gummy exudation mixed with frass and excrement at or near the base of the tree. The parent moth lays the egg^ singly (from May to July, according to latitude) on the bark of the tree, usually near the base. The young larva burrows into the bark and mines between it and the sapwood during the .summer and fall. It is quiescent during- the winter, but resumes feeding in the early spring, reaching full growth by May or June. The caterpillar is then a little over 1 inch in length, soft, and pale yellowish in color, with a shining, dark-brown head. It transforms to a chrysalis within an elongate cocoon just beneath or sometimes outside of the bark. The moths emerge in May or June. The female has dark-blue fore-wings; the male has clear ones. It primarily attacks peach, but sometimes cherry and plum. There is but one brood each year. the entrance to a small burrow lined with silk, within which the young larva of this insect passes the winter. It is now of a yellowish color, with the head and thoracic segments, as well as the last segment, almost black. Early in spring, when the leaves are coming out, the larvae abandon their burrows and attack the tender leaf shoots, boring into them from a point a little below the apex, and when one shoot commences to dry the larva leaves it and attacks another. In about two weeks the larva is full grown, and pupates in a slight open cocoon attached to the bark or among the shriveled leaves. The tiny, grayish moth issues in May. Two broods follow this, the larvae boring in the young twigs or sometimes in the immature fruit. The larva from the second brood makes the little burrows in the bark in which the insect passes the winter. The peach twig-borer feeds on all stone fruits. the case remaining attached to the tree all winter. In May the young hatch, and at once start to make little cases for themselves, which they enlarge as they grow. When read}^ to pupate, the caterpillar fastens its case to a twig and transforms to the chrysalis. The male moth appears in August. There is but one brood a year. OTHER CATERPILLARS. On the apple tree in winter one may find several other caterpillars in various stages of development. It carries with it a case the tip of which is curved over, the whole about one-eighth inch long. It feeds on the buds and leaves in spring. In the fall it fastens itself securely to the twig, and thus passes the winter in an immature condition. Another is the cigar-case bearer (Coleophora Jletc her ella Fern.). It has a life history similar to the preceding, but its case is straight, not curved. Both feed on the pear and quince. Small, elongate, white, ribbed cocoons, nearly one-fourth of an inch long, often in clusters, are sometimes seen on apple bark in winter. They indicate the presence of the apple-leaf bucculatrix (B. pomifoliella Clem.). In spring the tiny, delicate moths issue from the cases. The larvae mine the leaves. There are two broods annually. Small, inconspicuous cases, covered with particles of dirt and bark, are, at times, found on the bark of the apple and pear. These contain the half -grown larva of the bud-moth (Tmetocera ocellana Schif., figs. 34 and 35). In spring the larva feeds on the buds and young leaves, webbing the leaves in a bunch or nest. They pupate within this nest. The moth issues in Jul}^, and is a grayish insect with a creamy white patch on each fore-wing. During the summer the young larvae partially skeletonize the leaves, feeding beneath a thin silken web. As winter approaches they migrate to the twigs and form their hibernating cases. There is but one brood a 3^ear. Beetles are easily known by the hard, coriaceous fore-wings that cover and protect the back of the abdomen. Both in the larval and the mature conditions they have biting mouth-parts, and injury is sometimes done by both the grub and the beetle. The grubs, to reach the adult condition, pass through a complete change or metamorphosis, like caterpillars, but do not spin a silken cocoon. The grubs do not have the prolegs that are found in caterpillars. The forms to be noticed below may be arranged as follows: Discolored places on the bark near the base of the trunk may indicate the presence of this borer. Sometimes the bark cracks over the burrow and allows the frassor "sawdust" to drop out, and often there4 is some exudation of sap. Every unnatural-looking spot near the base of the tree should be examined. The adult of this borer is a grayish, long-horned beetle with two white stripes along its back. They appear in June and July, and lay their eggs in little slits in the bark made by the beetle near the base of the trunk. The larva? or grubs soon hatch and bore beneath the bark, feeding on the sapwood and inner bark, and making flat, shallow cavities, partially filled with frass. The grubs are nearly cylindrical, pale yellowish in color, and when fullgrown about an inch long. On the approach of winter they work downward, often below the surface of the ground. In spring they begin to feed again, boring upward. In this manner they feed all summer until cold weather, when they again hibernate. In the spring they resume work, but now they bore more irregularly and further into the tree. In early fall they bore close to the surface, work back a little, and then pupate. Winter is passed in this condition, and in June the beetles cut circular holes in the bark and escape. It thus takes three years to reach maturit}^ This borer also infests pear and quince, but not so f requentry as the apple. indicate the presence of this insect. They are, however, often found farther up the trunk, and even on the larger branches. The adult is a dark, metallic beetle, rather flat, and about one-half inch in length. The female deposits her eggs in crevices of the bark on the south side of the tree, usually during June and July, but sometimes neath the surface, leaving a flattened burrow filled with its frass. Sometimes, when more mature, they bore deeper into the sapwood. The full-grown larva is nearly an inch in length, pale yellowish in color, with the segment next to the head greatly enlarged and flattened. In the spring it bores out nearly through the bark, then moves back a little and pupates. In about three weeks the beetle cuts an elliptical hole in the bark and escapes. There is one brood each year. It attacks apple, pear, cherry, plum, and quince. The larva of this insect bores long, sinuate galleries beneath the bark and sapwood of pear, killing the wood and causing the bark above to crack. The elongate bronzy beetle makes its appearance in May or early June, and lays its eggs in crevices of the bark. The slender, whitish larva burrows beneath the bark, always downward. In the fall the larva becomes dormant, and is then about 1 inch long, quite flat, whitish or yellowish in color, with a brown head, and the segment next to the head much enlarged. In spring the larva resumes feeding and makes broader burrows tban in the first year. In late summer or early fall, when full fed. it bores about one-fourth inch into the wood, and there forms an elon- gate cell parallel with the bark and connected to the outside by an exit hole. Within this cell it winters, pupates in April, and the beetle issues in May or June. It thus takes about two years to reach maturity. adult insect, a tiny black beetle, appears in the latter part of March to the middle of May, and burrows through the bark. Between the bark and sapwood the female makes a burrow and lays her eggs along each and in about three weeks are ready to pupate at the end of the gallery. In about a week the beetles bore out from their burrows. The result is that the bark is loosened and sometimes the tree girdled. When the}T attack peach there is a great exudation of sap and a consequent weakening of the tree. There are two and probably throe broods ;i year, but as they start at different times the broods become mixed. It attacks all kinds of fruit trees, and prefers trees that are dying, diseased, or weakened by other insects, but healthy trees are not exempt. In the fall and winter the adults of this insect bore into twigs of apple and other fruits, as indicated in fig. 41, J. Cutting back from this hole one will find this borer in tin4 adult state — a cylindrical brown beetle about one-third of an inch long. These holes are their hibernating quarters. In the spring the insect works in grape canes, causing the withering of new shoots, as indicated at tig. 41, f. In the spring the beetles emerge and insert their eggf< in diseased or dyingtwigs of grape, maple, or other plants; the larva bores through the center of the twig until fall, when it pupates. The beetle issues in late fall, and there is but one brood a year. It attacks chiefly appie, pear, peach, plum, and grape. The mites are not insects, although related to them. They are recognized by lacking the distinction between the head and thorax and by the absence of antennae. There are usually four pairs of legs. but in the pear-leaf blister-mite and its allies there are but two pairs. Besides the pear-leaf blister-mite, which is treated below, there are often found upon fruit trees in winter numbers of tiny, roundish, red eggs. These belong to a mite known as the clover mite (Bryobia />r<itensis Gar.). They rarely do damage to fruit trees in the East, but feed on clover and similar plants. This is a microscopic mite about one one-hundred and fiftieth of an inch long, with a slender bod}T provided with two pairs of legs near the head end. Although each mite is so small as to do little damage of itself, it may become the parent of a vast assemblage capable of doing a great amount of injury. During the winter the mites remain hidden between the bud scales. Early in spring the mites move to the young unfolding leaves, eat through the under surface, and feed on the interior substance of the leaf. Here the mites increase a thousandfold. Some of these mites move out to form new galls, until a leaf becomes thickly spotted with them. Their feeding causes a thickening of the leaf at that spot, commonly called a blister or gall. This blister is at first of a reddish color, but it gradually turns brown, and finally black. In early fall, when the leaves ripen, the mites leave their galls and take refuge in the buds for the winter. INSECTS INFESTING FRUITS. Although few of the insects infesting fruit are liable to be transported upon nursery stock, several of them arc such destructive pests as to merit the attention of all interested in horticulture. The codling moth (Carpoca/psa pomonella Linn.) passes the winter as a caterpillar in a cocoon in crevices or under loose pieces of the bark. However, they are not apt to occur on nursery trees. The cocoon is made of whitish silk quinces. The apple maggot {Rhagoletis pomonella Walsh, tig. ±'l) is a twowinged fly that appears in June and lays its eggs just beneath the skin of apples. The white maggots, upon hatching, burrow throughout the apple in various directions. When full-fed the maggot drops to the ground, under which it pupates and emerges as a fly the next spring. The cherry fruit-fly {Rhagoletis cmgvlata Loew. tig. 48) infests cherry in much the same manner as the apple maggot infests apples, and has a similar life history. The plum curculio {Con,otrachelus nenuphar Herbst.) is a small, gra}Tish weevil that passes the winter under the bark of a tree or among rubbish. In spring it deposits eggs within the plum (peach or cherry) and then cuts a crescentic slit in the skin near by. The larva or grub soon hatches and feeds in the fruit, causing it to ripen codling moth also attacks pears and prematurely and fall. The grub, when full -grown, passes into the ground and there pupates, the beetle issuing in the fall. The beetle has a peculiar habit of dropping from the tree when disturbed. The quince curculio (Conotrachelus crat&gi Walsh.) is a very similar insect to the plum curculio. It is the cause of knotty or wormy quinces. The weevil lays her eggs in little pits of the quince eaten by the parent for that purpose. The grubs feed in the quince till the early- fall, when they leave it and burrow beneath the ground. Here they pass the winter, pupating in early spring. The pear midge (Diplosis pyrivora Riley) is a tiny, two- winged fly much like the Hessian fly, that appears in the spring and lays its eggs in young pears. The larvae feed near the core, causing the fruit to shrivel and drop. When full-fed they leave the fruit and pupate about an inch or so beneath the surface of the ground. The winter is passed in this condition, and the flies emerge the following spring.	11,092	common-pile/pre_1929_books_filtered	cipalin00unit	public_library	public_library_1929_dolma-0017.json.gz:1298	https://archive.org/download/cipalin00unit/cipalin00unit_djvu.txt
drIDKV5AQFL36WHv	Engineering Economics	3.4 Equations of Economic Equivalence In section 3.3, we discussed the four key principles of economic equivalence. We need these when analyzing cash flows and evaluating economic equivalence. There are several cash flow patterns that frequently occur. Fortunately, equations have been developed to facilitate the cash flow analysis. We refer to cash flow patterns as series. There are four basic types of cash flow series: - Uniform series - Linear gradient series - Geometric gradient series - Complex (random) cash flows In this section, we will take a closer look at each one of these series and their analysis. All of the equations used to analyze each of these types of series are based on the single cash flow equation developed in section 3.2.2 based on the concept of compound interest. 3.4.1 Single Cash Flow Single cash flows involve a single financial transaction at a point in time. An example of a single cash flow is a purchase of a car with a single payment. The alternatives in example 3.3 both represent single cash flows. The future value formula 3.6 from section 3.2.2 is used to analyze single cash flows: Previously in this chapter, this formula was used to calculate the future value of investments, deposits or loans when accruing compound interest. The formula calculates a cash flow’s economic equivalent for a given discount rate and a point in time. In this case, we use a discount rate instead of an interest rate, although depending on the context the interest rate may be equal to the discount rate. The future value formula enables us to “move” cash flows to a future point in time. By rearranging the future value formula we obtain present value (P) formula, which enables us to “move” cash flows to the present. The formula for discounting single cash flows, thus, becomes: (3.8) Now, let’s look at an example of how single cash flow analysis is performed. Single Cash Flow Example You are an employee at Dunder Mifflin Paper Company. Your boss, Michael, offers you two options for a salary bonus: you can either accept a $1000 bonus now, or you can wait and take a $1200 bonus two years from now. Which one should you choose if your discount rate is 5% per year? Solution We tackle this problem by finding the economic equivalent of the $1200 bonus – in other words, we use discounting to “move” the $1200 bonus to current year to find its present value. We then compare the $1200 bonus to the $1000 bonus to see which one would be the better choice. Step 1: Discount the $1200 bonus for two interest periods (two years) at 5% annually to obtain its present value. Here, and . Thus, using formula 3.8: Step 2: Compare the options. At a 5% discount rate, the $1200 bonus has a present value greater than $1000, so the $1200 bonus should be chosen. 3.4.2 Uniform Series A uniform series, sometimes called an equal-payment series, is a cash flow series in which the same amount of money is paid or received in two or more sequential periods, as shown in Figure 3.4. These types of equal payments are also referred to as annuities. This type of cash flow series is probably familiar to you: many long-term loans, such as house mortgages and car loans, involve a fixed monthly payment for a set length of time. These arrangements allow buyers to spread out payments on large purchases (like cars and houses) that would be difficult for most people to buy in one lump-sum. An example of a uniform series is illustrated by a cash flow diagram below: We can analyze equal payment series scenarios in four different ways. These formulas can be used to convert uniform cash flows into an equivalent single cash flow, or distribute a single cash flow into an equivalent uniform series. For further information on how these formulas were developed, refer to Section 3.4.7 for the full derivation. - Present-value-from-payment formula: used to calculate the present value, P, from the regular payment A (given A, find P). (3.9) This formula can be used to answer questions such as “how much can I borrow to buy a car if I can afford monthly payments of $500?” - Payment-from-present-value formula: used to calculate the regular payment, A, from the present value P (given P, find A). This is used when distributing a large lump-sum value into smaller, equal payments. (3.10) For example, “how much will my monthly car payment be if I borrow $10 000 to buy a car now and plan to pay it back over 5 years?” - Future-value–from-payment formula: used to calculate the future value, F, from the regular payment A (given A, find F). It is commonly used to determine how much an account or loan will be worth after N periods of regular contributions. (3.11) As an example: “if I save $500 every month, how much money will I have 5 years from now?” - Payment-from-future-value formula: used to calculate the regular payment, A, from the future value F (given F, find A). This formula is useful when trying to calculate the size of payment required to have a certain amount, F, in the future. (3.12) For example, “if my goal is to have $10,000 in 5 years, how much will I have to put into my savings account each month?” An important note regarding timeframes: in the above formulas, N denotes the number of periods in the uniform series, i denotes the interest (or discount rate) per period, and A denotes the equal cash flow per period. N, i, and A must all be in the same time frame. If an example requires calculating a monthly payment (A), then N must be months and i must be the monthly interest rate. Note that calculating the present value of a uniform series will place the present value one period before payments begin. As shown in the cash flow diagram (Figure 3.4), if payments start in period 1, then P occurs in period 0. Let’s look at some examples. Uniform Series Example #1 Aladdin wants to borrow $12,000 and pay it off in equal monthly payments over a 5-year period. If the monthly interest rate is 0.75%, compounded monthly, how much would each payment be? Solution N = 5 years or 60 months, i = 0.75% = 0.0075, and P = $12,000. To solve for A: Thus, the monthly payment would be $249.10. Notice, this means Aladdin ends up actually paying a total of $14 946 for his $12 000 loan ($249.10*60), where $2 746 is the total interest paid to the lender on top of the loan. Uniform Series Example #2 Brook wants to start saving for retirement. She plans to deposit $500 per month into a savings account that earns 6% per year (compounded annually). How much money will Brook have in the account after 25 years? Solution Here, we have monthly payments and we need to find the future value of the account, so we will use the future-value-from-payment formula 3.11. But note the units: we are dealing with monthly payments, but interest is applied annually. This means we must use the end of period convention – treat all monthly deposits within each year as if they were all deposited on the last day of the year (discussed in Front material). So, we have: A = ($500/month)(12 months/year) = $6000/year i = 6% per year N = 25 years So, after 25 years, Brook will have $329 187.07 in her account. Note that without any interest she would have only saved up $150 000 ($6000 per year x 25 years). Interest more than doubled the money! Defered Annuity Example Given the schedule of cash flows in Figure 3.5, calculate the present value, at period 0, using an annual discount rate of 7%. Solution In this case, we have A, and need to find P, so we will use the present-value-from-payment formula 3.9. But note: this formula will give us the present value in period 2 (see Figure 3.6). We need to then “move” it to period 0 (see Figure 3.7). Step 1: Find the present value (P2) of the uniform series. A = $2000 i = 7% N = 5 years Step 2: Discount the P2 cash flow to period 0. Now that we have a single cash flow at period 2, we can discount it to obtain the present value at period 0: Therefore, the value of the uniform series at period 0 is $7162.54. 3.4.3 Linear Gradient Series A linear gradient series is a series of cash flows which increase or decrease by a constant amount every period. An illustrative example is found in Figure 3.8 below. As we see, in each period the amount is increasing by $5. This is the gradient G. In the cash flow diagram above, the cash flow in period 1 is $10. In the second period, we add G to obtain a value of $15. In the third period, we add two times the gradient to get a cash flow of $20… and so on. Note that in Figure 3.8 cash flows are increasing due to a positive G. However, G can also be negative, so that each subsequent payment will be smaller than the previous one by G. When calculating the linear gradient series, we must break up the cash flows into two series: a uniform series and a linear gradient series with a cash flow of zero in period 1, as shown below. In the Figure 3.8, A would be $10 and G would be $5. Notes on using the linear gradient series: - As with the uniform series that calculating the present value of a linear gradient series places the present value one period before the cash flows begin; if cash flows begin in period 1, the P will occur in period 0. - N is the number of interest periods, including the period in which the gradient’s cash flow is zero. - G can be positive or negative. If the cash flows are increasing each period, then G is positive; if they are decreasing, then G is negative. - A is always equal to the cash flow in the first period. Formulas for analyzing a linear gradient series: - Present value of a linear gradient series: used to calculate the present value (in period 0) of a linear gradient portion of the series beginning in period 1 (given G, find P). (3.13) This formula along with the corresponding uniform series formula can be used to answer questions such as: “what is the present value of a 10 year maintenance contract for which the payments increase by $1000 per year?” - Future value of a linear gradient series: used to calculate the value of a linear gradient portion of the series at the end of the last period in the series (given G, find F). (3.14) This formula along with the corresponding uniform series formula can be used to determine, for example: “if I open an account and make deposits increasing the amount deposited by $100 each month, how much will I have in the account after 24 months?” - Converting a linear gradient series to a uniform series: used to convert a linear gradient series to a uniform series with the same payment timing (given G, find A). (3.15) After adding this result to the uniform portion of the cash flow series, this formula can answer questions, such as: “how much would I have to pay if I were to make equal monthly payments on a loan instead of increasing each payment by $100 each month for the next 12 months?” To see how these formulas were derived refer to Section 3.4.7. Note that, as before, i is the discount or interest rate per period and N is the number of periods. Do not forget that these formulas only apply to the gradient portion of the series. If the series in the problem is split into a gradient series and a uniform series as discussed in this section, then the value of the uniform series must be added to the gradient series value to get the total value of the series. Let’s see some examples of how these formulas are applied. Linear Gradient Series Example #1 Gary decides to start saving for his newborn twin daughters’ post secondary education. He can afford to save $1000 in the first year, $1100 in the second year, $1200 in the third year, and so on, increasing the amount by $100 each year. The savings account pays 5% interest, compounded annually. How much money will he have in the account after 18 years? Solution Step 1: Draw the cash flows. Step 2: Split up the cash flow series into two components. Looking at the cash flow in this problem (Figure 3.10) we can see that it increases by a constant amount ($100) each, implying a linear gradient. The cash flow in the first period is not zero, so we must split the original cash flow schedule into a linear gradient series and a uniform series. The cash flows in the uniform series are equal to the savings in the first period – in this case, A = $1000. The gradient is positive, since the cash flows are steadily increasing. For the linear gradient series, G = $100. Step 3: Verify that payments and interest rate have the same time units. The account pays annual interest and deposits are made annually, so the values have the same time units. A = $1000 per year G = $100 per year i = 5% per year N = 18 years Step 3: Calculate the future values of the linear gradient and uniform series using formulas 3.14 and 3.11. Step 4: To calculate the total future value after 18 years, add the future values of the uniform series and the linear gradient series. Thus, after contributing $33 300to the account for 18 years, Gary will have saved $48 397.15 for his daughters’ education. Linear Gradient Series Example #2 A machine shop is planning to buy a CNC (computer numerical controlled) mill to automate simple steps for large-scale production jobs, saving labour costs. The mill costs $100 000. Using the mill would result in the following labour cost savings: \| Year \| 1 \| 2 \| 3 \| 4 \| 5 \| 6 \| \| Savings ($) \| 28000 \| 26000 \| 24000 \| 22000 \| 20000 \| 18000 \| If the company’s discount rate is 8%, should the mill be purchased? Solution Step 1: Draw cash flows. Note that these values are savings. In situations like this we assume that total cost, which is not stated, remains constant throughout. As a result, these savings also imply that profits increase by the same amount. So we can draw the cash flow diagram as follows: Step 2: Separate the cash flows into a uniform series and a linear gradient series. Looking at the cash flow in this problem (Figure 3.12), we can see that it decreases by a constant amount ($2000) each year throughout the life of the machine, implying a linear gradient. The cash flow in the first period is not zero, so we must split the original cash flow schedule into a linear gradient series and a uniform series. The cash flows in the uniform series are equal to the savings in the first period, so in this case, A = $28,000. The gradient is negative, since the cash flows are steadily decreasing. Thus, G = –$2000. Step 3: Verify that payments and interest rate have the same time units. Savings in this example are projected on the annual basis and we have an annual discount rate, so the values have the same time units. A = $28,000 per year G = -$2000 per year i = 8% per year N = 6 years Step 4 : To determine if the mill is a good investment, we need to find the present value of the overall cash flow series by adding the present values of the two components. We use formulas 3.9 and 3.13 to find present values: Therefore, since the present value of the savings, $108 394.08, is greater than the cost of the mill, $100 000, purchasing the mill is a good financial investment. Even though the difference of the present value of the savings and the cost of the mill is only $8394.08, the actual saving from the mill are $138 000. 3.4.4 Geometric Gradient Series The geometric gradient series is a series of cash flows in which each cash flow increases (or decreases) by a constant percentage (in contrast to the linear gradient series, where each cash flow increases or decreases by a constant amount). The percentage change is called the geometric gradient, denoted by g. The cash flow values are calculated similarly to compound interest: if the cash flow in the first year is A1, then in the second year the cash flow will be A1(1 + g), in the third year it is A1(1 + g)2, and so on. This is illustrated in the cash flow diagram below. As evident from Figure 3.14, just like in the case with compound interest, geometric gradient results in exponential growth. Thus, cash flows are highly sensitive to the gradient value. The gradient g can be positive or negative. Positive values of g lead to a rise in subsequent cash flows, while negative values of g cause the cash flows to decrease over time. To find P we need to “move” all of the cash flows to period 0. The first step in solving the gradient portion of the series is to check whether the geometric gradient (g) is equal to the discount rate (i). If they are not equal, the formulas are: - When : (3.16) (3.17) If they are equal, the denominator of the first term on the right-hand side of each equation will equal 0 and cannot be solved. Thus, the following formulas need to be used instead: - When (3.18) (3.19) These formulas are used to answer questions such as: “what is the present (or future) value of a project that is expected to yield $1000 in profit this month, and the profit is expected to increase by 5% every following month for 11 months?” Important note: be careful not to confuse i and g. The geometric gradient, g, is the rate at which the cash flows increase or decrease in subsequent periods, which reflects changes in the nominal value of the cash flows. The discount rate, i, is used to account for the time value of money. When using the geometric gradient series formulas: - N is the number of interest periods, including the initial period where the gradient is equal to zero. - The discount rate, i, and the gradient, g, must be specified. The MARR (which will be covered in chapter 5) is often used as the discount rate. - The cash flow is NOT divided into uniform and gradient components. It can be solved directly using the above formulas. Let’s see some example problems where geometric gradient series formulas are used. Geometric Gradient Series Example Brad, a civil engineer, is coordinating a project to build a new stadium in Regina. The cost of stadium construction is estimated to be $278 million.[6]Part of the sum will be collected in the form of grants from the Provincial Government, the City of Regina and the Saskatchewan Roughriders. The rest, which amounts to $100 million, will be loaned by the Province for a period of 30 years at 3.5% interest, compounded annually. The loan is to be repaid on a monthly basis with equal payments throughout the entire term. The City will use ticket sales revenues for some of the events held at the stadium to make the loan payments. In the first year, the revenues are expected to be equal to the total loan payments for the year. The project management team expects these revenues to increase by 5% each year. Does the present value of the total revenue from ticket sales exceed the value of the loan? (Assume 6% discount rate) Solution First, we need to determine the monthly loan payments, so that we can determine how much is to be repaid in the first year, which also tells us the expected ticket revenues in the first year. Thus, we will solve this problem in two stages: calculating the equal payments of the loan and calculating the total revenues from ticket sales. Part 1: Step 1: To calculate the equal payment value, we use the payments-from-present value formula 3.10. We have the following information: N = 30, i = 3.5% = 0.035, and = $100 million. To solve for A: So, the annual loan payments are $5.44 million. Part 2: Step 3: Now that we know the value of the yearly loan payment, we can conclude that ticket sales in the first year are expected to be $5.44 million. Since, project management team expects the revenues to increase by 5% each year, this implies a geometric gradient series with the first cash flow A=A1=$5.44 million. To find the present value of the total revenue from ticket sales at the end of 30 years, the present value formula for geometric series is used. Note that , so we use formula 3.16 to calculate future value of the total revenue. Thus, we have: N = 30, i = 6% = 0.06 g = 5% = 0.05, and A=A1=$5.44 million So, the present value of the total revenue from ticket sales exceeds the value of the loan by $36 million. 3.4.5 Complex Cash Flows The purpose of cash-flow equations is to simplify calculations required for cash flow analysis. It is usually much more convenient to group several cash flows together for one calculation rather than to discount each cash flow separately. To apply the appropriate formulas, it is important to identify the type of cash flow series. However, in practice, it is not always apparent what type of series we are dealing with. Cash flows can be seemingly “random” or change drastically over the analysis period. We call these complex cash flows. To tackle complex cash flows problems, the trick is to seek out patterns in the cash flow schedules and “deconstruct” them into different cash flow series, which may allow us to use the cash-flow equations. The example below demonstrates how complex cash flows can be approached. A complex cash flow example Given the schedule of cash flows in Figure 3.15, find the total present value of the series at year 0 using a discount rate of 8%. To find the present value of this cash flow series, we must “move” each amount to year 0. One way to do so is to discount each cash flow one-by-one using the present-value formula 3.8 for single cash flows and sum them. However, it may be less time-consuming to recognize that the individual flows can be grouped into separate series. Step 1: Examine the cash flow diagram for patterns. One set of patterns is as follows: Note that this is not the only possible way to segment the cash flows, but this is the segmentation we will use to solve the problem. Step 2: Now to calculate the total present value we will begin by moving each of the three series to period 0. Segment A: The uniform series The uniform series begins in year 2, so we calculate its “present” value from the uniform series formula 3.9 to get the series’ value in year 1, which we will call P1. Then, we move P1 to year zero by discounting it over one year (see Figure 3.17). Segment B: The single payment To determine the present value of the single payment in year 4 we discount it 4 years to bring it to the present, as shown in Figure 3.18: Segment C: The linear gradient series Recall that linear gradient series must be split into two series: a uniform series and a gradient series. In this example, the first cash flow of the linear gradient series is -$1000, so the uniform series will have equal payments, A = -$1000. Each consecutive outflow increases by $500, so the gradient, G = -$500 (recall, we treat outflows as negative values). The first cash flow of the segment occurs at year 5, so when we use equations to calculate the present value, the resulting present value is actually in year 4. So we must remember to “move” it to year 0, as shown in Figure 3.19: We now “move” the year 4 present value to year 0: Step 3: To obtain the present value of the complete series we sum the present values of each segment: Total P = PA+ PB + PC Total P = (-$1651.17) + (-$1470.06) + (-$4143.50) = -$7264.73 So, the present value of the complete series (Total P) is -$7264.73. 3.4.6 Summary of Equations The summary of equations of economic equivalence is in Table 3.4 below. The final column of this table shows what is called factor notation – a short-hand way of expressing the equations. For example, let’s take a look at the present value for the single cash flows formula (row 1). So, . The right-hand side of this equation is called a factor. In factor notation this is shown as This factor is read as “P divided by F, given i and N”. So, to represent the entire equation, we write Similarly, using factor notation, the future this factor is expressed as (F/P, i, N), which is read as “F divided by P, given i and N”. The future value formula, thus, becomes: As you browse through the formulas in the table, you will notice that each equation requires multiplication involving a value of a cash flow (present value, future value, annuity, linear gradient) and a factor which depends on i and N (also g when dealing with geometric gradient series). To simplify calculations, factor values for different i and N have been tabulated in so-called compound interest factor tables for equations of economic equivalence. These tables allow to substitute already calculated factor values given interest-rate-and-number-of-periods scenarios in the appropriate formulas, hence decreasing the amount of necessary calculations. 3.4.7 Derivations The following sections provides derivations for the formulas used in Section 3.4. These derivations are provided to help you understand how the equations were developed. The ability to independently arrive at these derivations is not essential to being able to use them correctly or have a solid understanding of economic equivalence. Single cash flows formulas: - Future Value formula for single cash flows: (3.6) \| 1. Recall that the future value is equal to the present value and accumulated interest. \| \| \| 2. The interest earned in period 1, is equal to . So, the future value in period 1 becomes \| \| \| 3. In period 2, interest is applied to the ending balance in year 1, which is F1:. Thus, the future value in period 2 is \| \| \| 4. Since, from equation (2), F1= , we can substitute this into equation (3), yielding \| \| \| 5. This simplifies to \| \| \| 6. In period 3, interest is now applied to the present value in period 2, which is F2: . Hence, the future value in period 3 becomes \| \| \| 7. Since, from equation (5) , substituting the right-hand side from of the equation into equation (6) yields \| \| \| 8. Simplifying, we get \| \| \| 9. Continuing for N periods using the same steps, we get the future value formula for single cash flows for N periods and interest rate i . \| - Present value formula for single cash flows (present value with compound interest formula): (3.8) The present value formula can be obtained from the future value formula for single cash flows 3.6: \| 1. Recall the future value formula 3.6 \| \| \| 2. To obtain P, we divide both sides by . We now have the present value formula for single cash flows. \| Uniform Series formulas: - Present-value-from-payment formula: (3.9) \| 1. The present value is the sum of all discounted cash flows in the series. In a uniform series, each cash flow has a value of A. \| \| \| 2. Now we multiply both sides of the equation by . On the right-hand side, all denominators’ exponents decrease by 1. \| \| \| 3. We need to get the right-hand side in equation (2) from equation (1). To do that, first, we move to the left-hand side in equation (1). \| \| \| 4. We then add A to both sides of equation (3), which yields equation (4). \| \| \| 5. Now, we relate equations (1) and (4) to obtain an equation without series (5). \| From (1) and 3) \| \| 6. We now rearrange the terms in equation (5) to solve for . \| \| \| 7. Multiplying the terms inside the brackets in equation (6) by i we obtain the present-value-from-payment formula (7). \| This formula combined with the present-value formula for single cash flows 3.8 is used to derive the three remaining formulas: the payment-from-present value formula 3.10, the future-value-from-payments formula 3.11 and the payment from future value formula 3.12. - Payment-from-present-value formula: (3.10) The payment-from-present-value formula 3.10 and the present-value-from-payment formula 3.9 are reciprocals of each other: \| 1. Recall the present-value-from-payment formula 3.9 \| \| \| 2.To obtain A, we divide both sides by \| \| \| 3. Rearranging equation (2) we get the payment-from-present-value formula \| - Future-value–from-payment formula: (3.11) This formula can be obtained using the payment-from-present value formula 3.9 and the future value for single cash flows formula 3.6: \| 1. Recall the present-value-from-payment formula 3.9 \| \| \| 2. Next, recall the present value formula for single cash flows 3.8 \| \| \| 3. Substituting from equation (2) in equation (3) yields \| \| \| 4. Now we multiply both sides of equation (3) by \| \| \| 5. This, in turn, cancels out in the denominator in the term in square brackets on the right-hand side in equation (4). We get the future-value-from-payment formula \| - Payment-from-future-value formula: (3.12) The payment-from-future-value formula 3.12 and the future-value-from-payment formula 3.11 are reciprocals of each other: \| 1. Recall the future-value-from-payment formula 3.11 \| \| \| 2. Solving for A, we divide both sides by \| \| \| 3. Rearranging equation (2) we get the payment-from-future-value formula \| Linear Gradient Series Formulas: These formulas apply to the gradient series with linear gradient G as illustrated in Figure 3.20. - Future value of a linear gradient series formula: (3.14) \| 1. Future value of the linear gradient series can be thought of as a sum of future values of individual cash flows in the series: 0G, 1G, 2G…(n-2)G, (n-1)G. Let i be the discount rate for discounting cash flows. The future value of the gradient series can thus be expressed as \| \| \| 2. Now we multiply both sides of the equation (1) by and factor out G. We will need this equation after the next step. \| \| \| 3. We go back to equation (1) again and now we only factor out G \| \| \| 4.Next, we subtract equation (3) from equation (2). 4.1 We rearrange the terms on the right-hand side of the equation by writing the terms that include with the same power from equation (2) and (3) next to each other. This allows us to subtract and rearrange them next. 4.2 We leave the first term in the brackets; subtract the next two, obtaining as a result; we factor out from the two terms after the ellipsis getting ; and leave the last term in the equation. 4.3 Further opening the brackets and simplifying the equation we get equation (4) \| \| \| 5. Now we carry n out of the brackets in the right-hand side of equation (5) \| \| \| 6. Notice that the expression in the square brackets is geometric series, where the first term of the series is and each subsequent term is multiplied by . We can find the sum of the geometric series using the geometric series formula , where and . We write down the geometric series summation formula and substitute the values from the series in equation (5). After some algebraic manipulation, we obtain the sum of the geometric series, which is expressed by equation (6). \| \| \| 7. Now we substitute equation (6) in equation (5) to get rid of the series in the equation \| \| \| 8. Next, we solve for F by dividing both sides of equation (7) by i and rearranging the terms on the right-hand side of the equation, obtaining the future value of a linear gradient series formula \| - Present value of a linear gradient series formula: (3.13) The present value of a linear gradient series formula 3.13 can be obtained from the present value formula for single cash flows 3.8 and future value of a linear gradient series formula 3.14: \| 1. Recall the future value of a linear gradient series formula 3.14 \| \| \| 2. To obtain P, we divide both sides by from the present value formula for single cash flows 3.8 \| \| \| 3. Multiplying the two fractions, we get the present value of a linear gradient series formula \| - Converting a linear gradient series to a uniform series formula: (3.15) This formula can be derived from the present value of the linear gradient series formula 3.13 and the present-value-from-payment formula 3.9: \| 1. Recall the present value of a linear gradient series formula 3.13 \| \| \| 2. Also recall the present-value-from-payment formula 3.9 \| \| \| 3. We now substitute the right-hand side from equation (2) into the left-hand side of equation (1) \| \| \| 4. To solve for A, we divide both sides of equation (3) by \| \| \| 5. Rearranging and simplifying equation (4) we get the formula for converting linear gradient series to a uniform series \| Geometric Gradient Series Formulas: When - Present value for geometric gradient series formula: (3.16) \| 1.The present value of the geometric gradient series can be expressed as a sum of discounted values of individual cash flows in the series A1, A1(1+g), A1(1+g)2 … A1(1+g)N-1. Let i be the discount rate for discounting cash flows. The present value of the gradient series can thus be expressed as \| \| \| 2. We now factor out A1 in equation (1). We will need this equation after the next step. \| \| \| 3. Now we multiply both sides of the equation (2) by . \| \| \| 4. Next, we subtract equation (2) from equation (3). On the right-hand side of the equation, we rearrange the terms in brackets, placing same terms from equations (2) and (3) next to one another. Notice, that other than the first and the last terms in brackets, all the other terms will cancel out. So, rearranging the equation and canceling out the terms we get equation (4) \| \| \| 5. Now we solve for P. First, we divide both sides of the equation by = \| \| \| 6. Canceling out (1+i) in equation (5) and further rearranging and simplifying the equation, we get the present value for geometric gradient series formula for the case when . \| - Future value for geometric gradient series formula: (3.17) This formula can be derived from the present value for geometric gradient series formula 3.16 and the future-value-from-payment formula 3.6: \| 1. Recall the present value for geometric gradient series formula 3.16 \| \| \| 2. To obtain F, we multiply both sides by from the future value formula for single cash flows 3.6 \| \| \| 3. Multiplying the terms in equation (2) and simplifying the equation, we get the future value for geometric gradient series formula for the case when . \| When When discounting the cash flows in the case where the discount (interest) rate is equal to the geometric gradient, , all the cash flows have the same present value. This is because the cash flows are increasing at the same rate as they are being discounted, thus maintaining the purchasing power of the cash flow. Therefore, the formulas for this case will be different, although the approach used to derive these formulas is the same. - Present value for geometric gradient series formula: (3.18) \| 1. Like in the case where , the present value of the geometric gradient series can be expressed as a sum of discounted values of individual cash flows in the series. Now that the gradient and the discount rates are equal ( ), these cash flows are A1, A1(1+i), A1(1+i)2 … A1(1+i)N-1.The present value of the gradient series can thus be expressed as \| \| \| 2. To obtain F, we multiply both sides by from the future value formula for single cash flows 3.6 \| \| \| 3. Multiplying the terms in equation (2) and simplifying the equation, we get the future value for geometric gradient series formula for the case when . \| When When discounting the cash flows in the case where the discount (interest) rate is equal to the geometric gradient, , all the cash flows have the same present value. This is because the cash flows are increasing at the same rate as they are being discounted, thus maintaining the purchasing power of the cash flow. Therefore, the formulas for this case will be different, although the approach used to derive these formulas is the same. - Present value for geometric gradient series formula: (3.18) \| 1. Like in the case where , the present value of the geometric gradient series can be expressed as a sum of discounted values of individual cash flows in the series. Now that the gradient and the discount rates are equal (), these cash flows are A1, A1(1+i), A1(1+i)2 … A1(1+i)N-1.The present value of the gradient series can thus be expressed as \| \| \| 2. We now factor out A1 in equation (1). \| \| \| 3. On the right-hand side of equation (2) we have N terms, each being . The sum of these terms is . Substituting this expression into equation (2) yields the \| - Future value for geometric gradient series formula: (3.19) This formula can be derived from the present value for geometric gradient series formula 3.18 and the future-value-from-payment formula 3.6: \| 1. Recall the present value for geometric gradient series formula 3.18 \| \| \| 2. To obtain F, we multiply both sides by from the future value formula for single cash flows 3.6 \| \| \| 3. Multiplying the terms in equation (2) and simplifying the equation, we get the future value for geometric gradient series formula for the case when . \| [6] Note amounts in this problem are indicated in US dollars, so the amount in Canadian dollars will differ. However, this is irrelevant to the problem	8,505	common-pile/pressbooks_filtered	https://openpress.usask.ca/engecon/chapter/3-4-equations-of-economic-equivalence/	pressbooks	pressbooks-0000.json.gz:35399	https://openpress.usask.ca/engecon/chapter/3-4-equations-of-economic-equivalence/
KRrHOq4U73AOGJxu	7.5: "The New Woman"	7.5: "The New Woman" - - Last updated - Save as PDF The rising emphasis on spending and accumulation nurtured a national ethos of materialism and individual pleasure. These impulses were embodied in the figure of the flapper, whose bobbed hair, short skirts, makeup, cigarettes, and carefree spirit captured the attention of American novelists such as F. Scott Fitzgerald and Sinclair Lewis. Rejecting the old Victorian values of desexualized modesty and self-restraint, young “flappers” seized opportunities for the public coed pleasures offered by new commercial leisure institutions, such as dance halls, cabarets, and nickelodeons, not to mention the illicit blind tigers and speakeasies spawned by Prohibition. So doing, young American women had helped usher in a new morality that permitted women greater independence, freedom of movement, and access to the delights of urban living. In the words of psychologist G. Stanley Hall, “She was out to see the world and, incidentally, be seen of it.” Such sentiments were repeated in an oft-cited advertisement in a 1930 edition of the Chicago Tribune : “Today’s woman gets what she wants. The vote. Slim sheaths of silk to replace voluminous petticoats. Glassware in sapphire blue or glowing amber. The right to a career. Soap to match her bathroom’s color scheme.” As with so much else in the 1920s, however, sex and gender were in many ways a study in contradictions. It was the decade of the “New Woman,” and one in which only 10 percent of married women—although nearly half of unmarried women—worked outside the home. 16 It was a decade in which new technologies decreased time requirements for household chores, and one in which standards of cleanliness and order in the home rose to often impossible standards. It was a decade in which women finally could exercise their right to vote, and one in which the often thinly bound women’s coalitions that had won that victory splintered into various causes. Finally, it was a decade in which images such as the “flapper” gave women new modes of representing femininity, and one in which such representations were often inaccessible to women of certain races, ages, and socioeconomic classes. Women undoubtedly gained much in the 1920s. There was a profound and keenly felt cultural shift that, for many women, meant increased opportunity to work outside the home. The number of professional women, for example, significantly rose in the decade. But limits still existed, even for professional women. Occupations such as law and medicine remained overwhelmingly male: most female professionals were in feminized professions such as teaching and nursing. And even within these fields, it was difficult for women to rise to leadership positions. Further, it is crucial not to overgeneralize the experience of all women based on the experiences of a much-commented-upon subset of the population. A woman’s race, class, ethnicity, and marital status all had an impact on both the likelihood that she worked outside the home and the types of opportunities that were available to her. While there were exceptions, for many minority women, work outside the home was not a cultural statement but rather a financial necessity (or both), and physically demanding, low-paying domestic service work continued to be the most common job type. Young, working-class white women were joining the workforce more frequently, too, but often in order to help support their struggling mothers and fathers. For young, middle-class, white women—those most likely to fit the image of the carefree flapper—the most common workplace was the office. These predominantly single women increasingly became clerks, jobs that had been primarily male earlier in the century. But here, too, there was a clear ceiling. While entry-level clerk jobs became increasingly feminized, jobs at a higher, more lucrative level remained dominated by men. Further, rather than changing the culture of the workplace, the entrance of women into lower-level jobs primarily changed the coding of the jobs themselves. Such positions simply became “women’s work.” Finally, as these same women grew older and married, social changes became even subtler. Married women were, for the most part, expected to remain in the domestic sphere. And while new patterns of consumption gave them more power and, arguably, more autonomy, new household technologies and philosophies of marriage and child-rearing increased expectations, further tying these women to the home—a paradox that becomes clear in advertisements such as the one in the Chicago Tribune . Of course, the number of women in the workplace cannot exclusively measure changes in sex and gender norms. Attitudes towards sex, for example, continued to change in the 1920s as well, a process that had begun decades before. This, too, had significantly different impacts on different social groups. While gay males had to contend with increased policing of the gay lifestyle (especially later in the decade), in general they lived more openly in New York in the 1920s than they would be able to for many decades following World War II. 18 At the same time, for many lesbians in the decade, the increased sexualization of women brought new scrutiny to same-sex female relationships previously dismissed as harmless. 19 Ultimately, the most enduring symbol of the changing notions of gender in the 1920s remains the flapper. And indeed, that image was a “new” available representation of womanhood in the 1920s. But it is just that: a representation of womanhood of the 1920s. There were many women in the decade of differing races, classes, ethnicities, and experiences, just as there were many men with different experiences. For some women, the 1920s were a time of reorganization, new representations, and new opportunities. For others, it was a decade of confusion, contradiction, new pressures, and struggles new and old.	1,223	common-pile/libretexts_filtered	https://human.libretexts.org/Courses/Diablo_Valley_College/Hist_121%3A_History_of_the_United_States_after_1865_(Conrad)/07%3A_The_New_Era/7.05%3A_The_New_Woman	libretexts	libretexts-0000.json.gz:29015	https://human.libretexts.org/Courses/Diablo_Valley_College/Hist_121%3A_History_of_the_United_States_after_1865_(Conrad)/07%3A_The_New_Era/7.05%3A_The_New_Woman
xC4QV2nrXtq003bg	History of Western Civilization II	132 The World Fairs 29.1.3: The World Fairs World fairs during the late 19th century and early 20th centuries showcased the technological, industrial, and cultural achievements of nations around the world, sometimes displaying cultural superiority over colonized nations through human exhibits. Learning Objective Assess the World Fairs and their purpose in the late 19th and early 20th centuries Key Points - World fairs are international exhibits displaying the achievements of nations, largely focused on technological and industrial developments. - World fairs originated in the French tradition of national exhibitions that culminated with the French Industrial Exposition of 1844 held in Paris. - The Great Exhibition held in London in 1851 established many of the familiar components of world fairs and is usually considered to be the first international exhibition of manufactured products. - Since their inception, the character of world expositions has evolved and is sometimes categorized into three eras: industrialization, cultural exchange, and nation branding. - Also present in many world fairs at the time as well as in smaller local fairs were exhibits of people from the colonized world in their native environments, often with an explicit narrative of European superiority. Key Terms - The Great Exhibition - An international exhibition that took place in Hyde Park, London, from May 1 to October 11, 1851. It was the first in a series of world fairs, exhibitions of culture and industry that became popular in the 19th century, and was a much anticipated event. It was organized by Henry Cole and Prince Albert, husband of the reigning monarch Queen Victoria. It was attended by numerous notable figures of the time, including Charles Darwin, Samuel Colt, members of the Orléanist Royal Family, and the writers Charlotte Brontë, Charles Dickens, Lewis Carroll, George Eliot, and Alfred Tennyson. - human zoos - Public exhibitions of humans, usually in a so-called natural or primitive state. The displays often emphasized the cultural differences between Europeans of Western civilization and non-European peoples or other Europeans with a lifestyle deemed primitive. Some placed indigenous Africans in a continuum somewhere between the great apes and the white man. A world’s fair, world fair, world exposition, or universal exposition (sometimes expo for short), is a large international exhibition designed to showcase achievements of nations. These exhibitions vary in character and are held in various parts of the world. World fairs originated in the French tradition of national exhibitions that culminated with the French Industrial Exposition of 1844 held in Paris. This fair was followed by other national exhibitions in continental Europe and the United Kingdom. The best-known “first World Expo” was held in The Crystal Palace in Hyde Park, London, United Kingdom, in 1851, under the title “Great Exhibition of the Works of Industry of All Nations.” The Great Exhibition, as it is often called, was an idea of Prince Albert, Queen Victoria’s husband, and is usually considered to be the first international exhibition of manufactured products. It was arguably a response to the highly successful French Industrial Exposition of 1844; indeed, its prime motive was for Britain to display itself as an industrial leader. It influenced the development of several aspects of society, including art-and-design education, international trade and relations, and tourism. This expo was the most obvious precedent for the many international exhibitions considered world fairs. Since their inception in 1851, the character of world expositions has evolved. Three eras can be distinguished: industrialization, cultural exchange, and nation branding. The first era could be called the era of “industrialization” and covered roughly the period from 1800 to 1938. In these days, world expositions were especially focused on trade and were famous for the display of technological inventions and advancements. World expositions were the platforms where the state-of-the-art in science and technology from around the world were brought together. The world expositions of 1851 London, 1853 New York, 1862 London, 1876 Philadelphia, 1889 Paris, 1893 Chicago, 1897 Brussels, 1900 Paris, 1901 Buffalo, 1904 St. Louis, 1915 San Francisco, and 1933–34 Chicago were landmarks in this respect. Inventions such as the telephone were first presented during this era. The 1939–40 New York World’s Fair diverged from the original focus of the world fair expositions. From then on, world fairs adopted specific cultural themes forecasting a better future for society. Technological innovations were no longer the primary exhibits at fairs. From Expo ’88 in Brisbane onward, countries such as Finland, Japan, Canada, France, and Spain started to use world expositions as platforms to improve their national images. Colonialism on Display Human zoos, also called ethnological expositions, were 19th-, 20th-, and 21st-century public exhibitions of humans, usually in a so-called natural or primitive state. The displays often emphasized the cultural differences between Europeans of Western civilization and non-European peoples or other Europeans with a lifestyle deemed primitive. Some of them placed indigenous Africans in a continuum somewhere between the great apes and the white man. Ethnological expositions have since been criticized as highly degrading and racist. The notion of human curiosity and exhibition has a history at least as long as colonialism. In the 1870s, exhibitions of exotic populations became popular in various countries. Human zoos could be found in Paris, Hamburg, Antwerp, Barcelona, London, Milan, and New York City. Carl Hagenbeck, a merchant in wild animals and future entrepreneur of many European zoos, decided in 1874 to exhibit Samoan and Sami people as “purely natural” populations. In 1876, he sent a collaborator to the Egyptian Sudan to bring back some wild beasts and Nubians. The Nubian exhibit was very successful in Europe and toured Paris, London, and Berlin. Both the 1878 and the 1889 Parisian World’s Fair presented a Negro Village (village nègre). Visited by 28 million people, the 1889 World’s Fair displayed 400 indigenous people as the major attraction. The 1900 World’s Fair presented the famous diorama living in Madagascar, while the Colonial Exhibitions in Marseilles (1906 and 1922) and in Paris (1907 and 1931) also displayed humans in cages, often nude or semi-nude. The 1931 exhibition in Paris was so successful that 34 million people attended it in six months, while a smaller counter-exhibition entitled The Truth on the Colonies, organized by the Communist Party, attracted very few visitors—in the first room, it recalled Albert Londres and André Gide’s critiques of forced labor in the colonies. Nomadic Senegalese Villages were also presented. In 1904, Apaches and Igorots (from the Philippines) were displayed at the Saint Louis World Fair in association with the 1904 Summer Olympics. The U.S. had just acquired, following the Spanish–American War, new territories such as Guam, the Philippines, and Puerto Rico, allowing them to “display” some of the native inhabitants. According to the Rev. Sequoyah Ade: To further illustrate the indignities heaped upon the Philippine people following their eventual loss to the Americans, the United States made the Philippine campaign the centrepoint of the 1904 World’s Fair held that year in St. Louis, MI [sic]. In what was enthusiastically termed a “parade of evolutionary progress,” visitors could inspect the “primitives” that represented the counterbalance to “Civilisation” justifying Kipling’s poem “The White Man’s Burden.” Pygmies from New Guinea and Africa, who were later displayed in the Primate section of the Bronx Zoo, were paraded next to American Indians such as Apache warrior Geronimo, who sold his autograph. But the main draw was the Philippine exhibition complete with full size replicas of Indigenous living quarters erected to exhibit the inherent backwardness of the Philippine people. The purpose was to highlight both the “civilising” influence of American rule and the economic potential of the island chains’ natural resources on the heels of the Philippine–American War. It was, reportedly, the largest specific Aboriginal exhibition displayed in the exposition. As one pleased visitor commented, the human zoo exhibition displayed “the race narrative of odd peoples who mark time while the world advances, and of savages made, by American methods, into civilized workers.” Attributions The World Fairs “World’s fair.” https://en.wikipedia.org/wiki/World%27s_fair. Wikipedia CC BY-SA 3.0. “Human zoo.” https://en.wikipedia.org/wiki/Human_zoo. Wikipedia CC BY-SA 3.0. “Ota_Benga_at_Bronx_Zoo.jpg.” https://en.wikipedia.org/wiki/Human_zoo#/media/File:Ota_Benga_at_Bronx_Zoo.jpg. Wikipedia CC BY-SA 3.0. “International_Exhibition_Brussels_par_Privat-Livemont.jpg.” https://en.wikipedia.org/wiki/World%27s_fair#/media/File:International_Exhibition_Brussels_par_Privat-Livemont.jpg. Wikipedia CC BY-SA 3.0.	1,745	common-pile/pressbooks_filtered	https://library.achievingthedream.org/herkimerworldhistory2/chapter/the-world-fairs/	pressbooks	pressbooks-0000.json.gz:78778	https://library.achievingthedream.org/herkimerworldhistory2/chapter/the-world-fairs/
XPGiGnINDGqELrFA	5.3: The Quotient Rule of Exponents	5.3: The Quotient Rule of Exponents For any real number $a$ and positive numbers $m$ and $n$, where $m > n$. The Quotient Rule For Exponents is the following. $\dfrac{a^m }{a^n} = a^{ m−n}$ Note: Bases MUST be the same. Result will have the same base. Idea: From the last section, $x^3 = \textcolor{blue}{x \cdot x \cdot x} \qquad x^5 = \textcolor{red}{x \cdot x \cdot x \cdot x \cdot x}$ Their quotient $\dfrac{x^ 5 }{x^3} = \dfrac{\textcolor{red}{x \cdot x \cdot x \cdot x \cdot x }}{\textcolor{blue}{x \cdot x \cdot x }}= \dfrac{\textcolor{red}{\cancel{x \cdot x\cdot x \cdot x }\cdot x }}{\textcolor{blue}{\cancel{x \cdot x\cdot x }}}= \dfrac{\textcolor{red}{x \cdot x }}{1} = \textcolor{red}{x \cdot x}$. So, $\dfrac{x^5 }{x^3 }= x^{5−3 }= x^2$ Using the quotient rule of exponents to simplify expressions. - $\dfrac{k^3 }{k^2}$ - $\dfrac{r^{32} }{r^{21}}$ - $\dfrac{\sqrt{2}^ 7 }{\sqrt{2 }^4}$ - $\dfrac{(−7)^9 }{(−7)^6}$ - $\dfrac{(x \sqrt{5})^8 }{x\sqrt{ 5}}$ - $\dfrac{(xy)^{18} }{(xy)^{17}}$ Solution \| Expression \| Quotient Rule \| Base \| \| $\dfrac{k^3 }{k^2}$ \| $k^{3−2 }= k$ \| $k$ \| \| $\dfrac{r^{32} }{r^{21}}$ \| $r^{32−21 }= r^{11}$ \| $r$ \| \| $\dfrac{\sqrt{2}^ 7 }{\sqrt{2 }^4}$ \| $\sqrt{2 }^{7−4 }= \sqrt{2 }^3$ \| $\sqrt{2}$ \| \| $\dfrac{(−7)^9 }{(−7)^6}$ \| $(−7)^{9−6 }= (−7)^3$ \| $-7$ \| \| $\dfrac{(x \sqrt{5})^8 }{x\sqrt{ 5}}$ \| $(x \sqrt{5})^{8−1 }= (x \sqrt{5})^7$ \| $x\sqrt{5}$ \| \| $\dfrac{(xy)^{18} }{(xy)^{17}}$ \| $(xy)^{18−17 }= xy$ \| $xy$ \| Note: In this section the exponent of the numerator was greater than the exponent of the denominator. That won’t always be the case. The case where the exponent in the denominator is greater than the exponent in the numerator will be discussed in a later section. Use the quotient rule of exponents to simplify the given expression. - $\dfrac{−y ^{13} }{−y^7}$ - $\dfrac{(2x)^{25}}{ 2x}$ - $\dfrac{\sqrt{7 }^{17 }}{\sqrt{7 }^{12}}$ - $\dfrac{(−7)^9 }{(−7)^6}$ - $\dfrac{(x + y) ^{78}}{ (x + y)^{43}}$ - $\dfrac{\sqrt{xy }^{15 }}{\sqrt{xy }^{11}}$	405	common-pile/libretexts_filtered	https://math.libretexts.org/Bookshelves/Applied_Mathematics/Calculus_for_Business_and_Social_Sciences_Corequisite_Workbook_(Dominguez_Martinez_and_Saykali)/05%3A_Exponents_and_Exponent_Rules/5.03%3A_The_Quotient_Rule_of_Exponents	libretexts	libretexts-0000.json.gz:44058	https://math.libretexts.org/Bookshelves/Applied_Mathematics/Calculus_for_Business_and_Social_Sciences_Corequisite_Workbook_(Dominguez_Martinez_and_Saykali)/05%3A_Exponents_and_Exponent_Rules/5.03%3A_The_Quotient_Rule_of_Exponents
OkzLrcVsCXSpnX2E	8.1: Vocabulario. Las partes del cuerpo	8.1: Vocabulario. Las partes del cuerpo - - Last updated - Save as PDF - Romano Sánchez Domínguez - Imperial Valley College Objetivos Recognize vocabulary related to parts of the body El torso y las extremidades La cara y la cabeza - la frente (forehead) - la piel (skin) - los ojos (eyes) - la nariz (nose) - la boca (mouth) - los dientes (teeth) - los labios (lips) - la lengua (tongue) - el oído (ear [inside]) - la oreja (ear [outside]) - el cerebro (brain) - el cuello (neck) - el pelo o el cabello (hair) El torso y las extremidades - la espalda (back) - el pecho (chest) - los hombros (shoulders) - el estómago (stomach) - las piernas (legs) - los pies (feet) - las manos (hands) - los dedos (de las manos) (fingers) - los dedos de los pies (toes) - los brazos (arms) - la muñeca (wrist) - los huesos (bones) - los músculos (muscles) A Practicar Contribute! Did you have an idea for improving this content? We’d love your input. CC licensed content, Original - Vocabulario. Authored by : SUNY Oneonta with Lumen Learning. License : CC BY: Attribution CC licensed content, Shared previously - Forehead. Located at : https://pxhere.com/en/photo/1412284 . License : CC0: No Rights Reserved - La piel. Authored by : Tong Creator. Located at : https://pixabay.com/es/photos/la-piel-piel-morena-2016480/ . License : Other . License Terms : Pixabay License: https://pixabay.com/es/service/license/ - Eyes of a child in the letter hole. Authored by : Alex Grech. Located at : https://commons.wikimedia.org/wiki/File:Eyes_of_a_child_in_the_letter_hole.jpg . License : CC BY: Attribution - La boca. Located at : https://www.pxfuel.com/es/free-photo-oiovl . License : CC0: No Rights Reserved - Teeth. Authored by : Kjerstin Michaela. Located at : https://www.needpix.com/photo/729918/teeth-dentist-dental-mouth-white-hygiene-dentistry-smile-woman . License : CC0: No Rights Reserved - Lips. Authored by : Hans. Located at : https://pixabay.com/nl/photos/lippen-rood-gesmolten-gezicht-mond-64395/ . License : Other . License Terms : Pixabay license - tongue. Authored by : torbakhopper. Located at : https://www.flickr.com/photos/gazeronly/392125657 . License : CC BY: Attribution - ear anatomy. Authored by : BruceBlaus. Located at : https://commons.wikimedia.org/wiki/File:Blausen_0328_EarAnatomy_-_gl.png . License : CC BY: Attribution - ear. Located at : https://pxhere.com/es/photo/1527453 . License : CC0: No Rights Reserved - Authored by : TheDigitalArtist. Located at : https://pixabay.com/es/illustrations/cerebro-pensamiento-mente-idea-4314636/ . License : Other . License Terms : Pixabay license - Human back on gray background. Authored by : Genusfotografen. Located at : https://commons.wikimedia.org/wiki/File:Human_back_on_gray_background.jpg . License : CC BY-SA: Attribution-ShareAlike - Chest. Authored by : Matt Baume. Located at : https://www.flickr.com/photos/mattymatt/423814919 . License : CC BY-SA: Attribution-ShareAlike - Las piernas. Located at : https://p0.piqsels.com/preview/533/876/42/woman-in-red-jersey-kicking-the-ball.jpg . License : CC0: No Rights Reserved - Feet. Authored by : Kaique Rocha. Located at : https://www.pexels.com/es-es/foto/agua-al-aire-libre-colgando-dedos-de-los-pies-57646/ . License : CC BY: Attribution - Las manos. Authored by : Segopotso Makhutja. Located at : https://www.pexels.com/es-es/foto/dorado-hombre-manos-mirar-1136589/ . License : CC BY: Attribution - Toes . Authored by : sole_lover. Located at : https://commons.wikimedia.org/wiki/File:Toes_feet_1.jpg . License : CC0: No Rights Reserved - Arms. Authored by : Lilian White. Located at : https://commons.wikimedia.org/wiki/File:Rocket-yoga-01-4000px.jpg . License : CC BY: Attribution - Huesos del miembro superior. Authored by : Torax. Located at : https://es.Wikipedia.org/wiki/Archivo:Huesos_del_miembro_superior.svg . License : CC BY-SA: Attribution-ShareAlike - Anterior and Posterior Views of Muscles. Authored by : OpenStax. Located at : https://es.Wikipedia.org/wiki/Archivo:1105_Anterior_and_Posterior_Views_of_Muscles_esp.jpg . License : CC BY-SA: Attribution-ShareAlike - Icons. Provided by : The Noun Project. License : CC BY: Attribution . License Terms : Noun Pro License Public domain content - Authored by : mohamed mahmoud hassan. Located at : https://www.publicdomainpictures.net/es/view-image.php?image=261441&picture=dolor-de-estomago . License : CC0: No Rights Reserved	754	common-pile/libretexts_filtered	https://human.libretexts.org/Courses/Imperial_Valley_College/Espanol_en_Accion_II_(Sanchez-Dominguez)/08%3A_Capitulo_10_Vida_saludable/8.01%3A_Vocabulario._Las_partes_del_cuerpo	libretexts	libretexts-0000.json.gz:13847	https://human.libretexts.org/Courses/Imperial_Valley_College/Espanol_en_Accion_II_(Sanchez-Dominguez)/08%3A_Capitulo_10_Vida_saludable/8.01%3A_Vocabulario._Las_partes_del_cuerpo
Sr1qNAjWoCdn5M9y	Intermediate Algebra	Rational Expressions and Functions Solve Rational Inequalities Learning Objectives By the end of this section, you will be able to: - Solve rational inequalities - Solve an inequality with rational functions Before you get started, take this readiness quiz. Solve Rational Inequalities We learned to solve linear inequalities after learning to solve linear equations. The techniques were very much the same with one major exception. When we multiplied or divided by a negative number, the inequality sign reversed. Having just learned to solve rational equations we are now ready to solve rational inequalities. A rational inequality is an inequality that contains a rational expression. A rational inequality is an inequality that contains a rational expression. Inequalities such as and are rational inequalities as they each contain a rational expression. When we solve a rational inequality, we will use many of the techniques we used solving linear inequalities. We especially must remember that when we multiply or divide by a negative number, the inequality sign must reverse. Another difference is that we must carefully consider what value might make the rational expression undefined and so must be excluded. When we solve an equation and the result is we know there is one solution, which is 3. When we solve an inequality and the result is we know there are many solutions. We graph the result to better help show all the solutions, and we start with 3. Three becomes a critical point and then we decide whether to shade to the left or right of it. The numbers to the right of 3 are larger than 3, so we shade to the right. To solve a rational inequality, we first must write the inequality with only one quotient on the left and 0 on the right. Next we determine the critical points to use to divide the number line into intervals. A critical point is a number which make the rational expression zero or undefined. We then will evaluate the factors of the numerator and denominator, and find the quotient in each interval. This will identify the interval, or intervals, that contains all the solutions of the rational inequality. We write the solution in interval notation being careful to determine whether the endpoints are included. Solve and write the solution in interval notation: Step 1. Write the inequality as one quotient on the left and zero on the right. Our inequality is in this form. Step 2. Determine the critical points—the points where the rational expression will be zero or undefined. The rational expression will be zero when the numerator is zero. Since when then is a critical point. The rational expression will be undefined when the denominator is zero. Since when then is a critical point. The critical points are 1 and Step 3. Use the critical points to divide the number line into intervals. The number line is divided into three intervals: Step 4. Test a value in each interval. Above the number line show the sign of each factor of the rational expression in each interval. Below the number line show the sign of the quotient. To find the sign of each factor in an interval, we choose any point in that interval and use it as a test point. Any point in the interval will give the expression the same sign, so we can choose any point in the interval. The number is in the interval Test in the expression in the numerator and the denominator. Above the number line, mark the factor negative and mark the factor negative. Since a negative divided by a negative is positive, mark the quotient positive in the interval The number 0 is in the interval Test Above the number line, mark the factor negative and mark positive. Since a negative divided by a positive is negative, the quotient is marked negative in the interval The number 2 is in the interval Test Above the number line, mark the factor positive and mark positive. Since a positive divided by a positive is positive, mark the quotient positive in the interval Step 5. Determine the intervals where the inequality is correct. Write the solution in interval notation. We want the quotient to be greater than or equal to zero, so the numbers in the intervals and are solutions. But what about the critical points? The critical point makes the denominator 0, so it must be excluded from the solution and we mark it with a parenthesis. The critical point makes the whole rational expression 0. The inequality requires that the rational expression be greater than or equal to. So, 1 is part of the solution and we will mark it with a bracket. Recall that when we have a solution made up of more than one interval we use the union symbol, to connect the two intervals. The solution in interval notation is Solve and write the solution in interval notation: Solve and write the solution in interval notation: We summarize the steps for easy reference. - Write the inequality as one quotient on the left and zero on the right. - Determine the critical points–the points where the rational expression will be zero or undefined. - Use the critical points to divide the number line into intervals. - Test a value in each interval. Above the number line show the sign of each factor of the numerator and denominator in each interval. Below the number line show the sign of the quotient. - Determine the intervals where the inequality is correct. Write the solution in interval notation. The next example requires that we first get the rational inequality into the correct form. Solve and write the solution in interval notation: \| Subtract 1 to get zero on the right. \| \|\| \| Rewrite 1 as a fraction using the LCD. \| \|\| \| Subtract the numerators and place the difference over the common denominator. \| \|\| \| Simplify. \| \|\| \| Factor the numerator to show all factors. \| \|\| \| Find the critical points. \| \|\| \| The quotient will be zero when the numerator is zero. The quotient is undefined when the denominator is zero. \| \|\| \| Use the critical points to divide the number line into intervals. \| \|\| \| Test a value in each interval. \| \|\| \| Above the number line show the sign of each factor of the rational expression in each interval. Below the number line show the sign of the quotient. \| \|\| \| Determine the intervals where the inequality is correct. We want the quotient to be negative, so the solution includes the points between −2 and 6. Since the inequality is strictly less than, the endpoints are not included. \| \|\| \| We write the solution in interval notation as (−2, 6). \| Solve and write the solution in interval notation: Solve and write the solution in interval notation: In the next example, the numerator is always positive, so the sign of the rational expression depends on the sign of the denominator. Solve and write the solution in interval notation: \| The inequality is in the correct form. \| \| \| Factor the denominator. \| \| \| Find the critical points. The quotient is 0 when the numerator is 0. Since the numerator is always 5, the quotient cannot be 0. \| \| \| The quotient will be undefined when the denominator is zero. \| \| \| Use the critical points to divide the number line into intervals. \| \| \| Test values in each interval. Above the number line show the sign of each factor of the denominator in each interval. Below the number line, show the sign of the quotient. \| \| \| Write the solution in interval notation. \| Solve and write the solution in interval notation: Solve and write the solution in interval notation: The next example requires some work to get it into the needed form. Solve and write the solution in interval notation: \| Subtract to get zero on the right. \| \|\| \| Rewrite to get each fraction with the LCD \| \|\| \| Simplify. \| \|\| \| Subtract the numerators and place the difference over the common denominator. \| \|\| \| Factor the numerator. \| \|\| \| Find the critical points. \| \|\| \| Use the critical points to divide the number line into intervals. \| \|\| \| Above the number line show the sign of each factor in each interval. Below the number line, show the sign of the quotient. \| \|\| \| Since, 0 is excluded, the solution is the two intervals, and \| Solve and write the solution in interval notation: Solve and write the solution in interval notation: Solve an Inequality with Rational Functions When working with rational functions, it is sometimes useful to know when the function is greater than or less than a particular value. This leads to a rational inequality. Given the function find the values of x that make the function less than or equal to 0. We want the function to be less than or equal to 0. \| Substitute the rational expression for \| \| \| Find the critical points. \| \| \| Use the critical points to divide the number line into intervals. \| \| \| Test values in each interval. Above the number line, show the sign of each factor in each interval. Below the number line, show the sign of the quotient \| \| \| Write the solution in interval notation. Since 5 is excluded we, do not include it in the interval. \| Given the function find the values of x that make the function less than or equal to 0. Given the function find the values of x that make the function less than or equal to 0. In economics, the function is used to represent the cost of producing x units of a commodity. The average cost per unit can be found by dividing by the number of items Then, the average cost per unit is The function represents the cost to produce number of items. Find ⓐ the average cost function, ⓑ how many items should be produced so that the average cost is less than ?40. ⓐ ⓑ More than 100 items must be produced to keep the average cost below ?40 per item. The function represents the cost to produce number of items. Find ⓐ the average cost function, ⓑ how many items should be produced so that the average cost is less than ?60? ⓐ ⓑ More than 150 items must be produced to keep the average cost below ?60 per item. The function represents the cost to produce number of items. Find ⓐ the average cost function, ⓑ how many items should be produced so that the average cost is less than ?20? ⓐⓑ More than 60 items must be produced to keep the average cost below ?20 per item. Key Concepts - Solve a rational inequality. - Write the inequality as one quotient on the left and zero on the right. - Determine the critical points–the points where the rational expression will be zero or undefined. - Use the critical points to divide the number line into intervals. - Test a value in each interval. Above the number line show the sign of each factor of the rational expression in each interval. Below the number line show the sign of the quotient. - Determine the intervals where the inequality is correct. Write the solution in interval notation. Section Exercises Practice Makes Perfect Solve Rational Inequalities In the following exercises, solve each rational inequality and write the solution in interval notation. Solve an Inequality with Rational Functions In the following exercises, solve each rational function inequality and write the solution in interval notation. Given the function find the values of that make the function less than or equal to 0. Given the function find the values of that make the function less than or equal to 0. Given the function , find the values of x that make the function less than or equal to 0. Given the function find the values of x that make the function less than or equal to 0. Writing Exercises Write the steps you would use to explain solving rational inequalities to your little brother. Answers will vary. Create a rational inequality whose solution is Self Check ⓐ After completing the exercises, use this checklist to evaluate your mastery of the objectives of this section. ⓑ After reviewing this checklist, what will you do to become confident for all objectives? Chapter Review Exercises Simplify, Multiply, and Divide Rational Expressions Determine the Values for Which a Rational Expression is Undefined In the following exercises, determine the values for which the rational expression is undefined. Simplify Rational Expressions In the following exercises, simplify. Multiply Rational Expressions In the following exercises, multiply. Divide Rational Expressions In the following exercises, divide. Multiply and Divide Rational Functions Find where and Find where and Add and Subtract Rational Expressions Add and Subtract Rational Expressions with a Common Denominator In the following exercises, perform the indicated operations. Add and Subtract Rational Expressions Whose Denominators Are Opposites In the following exercises, add and subtract. Find the Least Common Denominator of Rational Expressions In the following exercises, find the LCD. Add and Subtract Rational Expressions with Unlike Denominators In the following exercises, perform the indicated operations. Add and Subtract Rational Functions In the following exercises, find where and are given. In the following exercises, find where and are given. Simplify Complex Rational Expressions Simplify a Complex Rational Expression by Writing It as Division In the following exercises, simplify. Simplify a Complex Rational Expression by Using the LCD In the following exercises, simplify. 7.4 Solve Rational Equations Solve Rational Equations In the following exercises, solve. no solution Solve Rational Equations that Involve Functions For rational function, ⓐ find the domain of the function ⓑ solve ⓒ find the points on the graph at this function value. ⓐ The domain is all real numbers except and ⓑ ⓒ For rational function, ⓐ find the domain of the function ⓑ solve ⓒ find the points on the graph at this function value. Solve a Rational Equation for a Specific Variable In the following exercises, solve for the indicated variable. for for for for Solve Applications with Rational Equations Solve Proportions In the following exercises, solve. Solve Using Proportions In the following exercises, solve. Rachael had a 21-ounce strawberry shake that has 739 calories. How many calories are there in a 32-ounce shake? calories Leo went to Mexico over Christmas break and changed ?525 dollars into Mexican pesos. At that time, the exchange rate had ?1 US is equal to 16.25 Mexican pesos. How many Mexican pesos did he get for his trip? Solve Similar Figure Applications In the following exercises, solve. is similar to The lengths of two sides of each triangle are given in the figure. Find the lengths of the third sides. On a map of Europe, Paris, Rome, and Vienna form a triangle whose sides are shown in the figure below. If the actual distance from Rome to Vienna is 700 miles, find the distance from ⓐ Paris to Rome ⓑ Paris to Vienna Francesca is 5.75 feet tall. Late one afternoon, her shadow was 8 feet long. At the same time, the shadow of a nearby tree was 32 feet long. Find the height of the tree. 23 feet The height of a lighthouse in Pensacola, Florida is 150 feet. Standing next to the statue, 5.5-foot-tall Natasha cast a 1.1-foot shadow. How long would the shadow of the lighthouse be? Solve Uniform Motion Applications In the following exercises, solve. When making the 5-hour drive home from visiting her parents, Lolo ran into bad weather. She was able to drive 176 miles while the weather was good, but then driving 10 mph slower, went 81 miles when it turned bad. How fast did she drive when the weather was bad? mph Mark is riding on a plane that can fly 490 miles with a tailwind of 20 mph in the same time that it can fly 350 miles against a tailwind of 20 mph. What is the speed of the plane? Josue can ride his bicycle 8 mph faster than Arjun can ride his bike. It takes Luke 3 hours longer than Josue to ride 48 miles. How fast can John ride his bike? mph Curtis was training for a triathlon. He ran 8 kilometers and biked 32 kilometers in a total of 3 hours. His running speed was 8 kilometers per hour less than his biking speed. What was his running speed? Solve Work Applications In the following exercises, solve. Brandy can frame a room in 1 hour, while Jake takes 4 hours. How long could they frame a room working together? hour Prem takes 3 hours to mow the lawn while her cousin, Barb, takes 2 hours. How long will it take them working together? Jeffrey can paint a house in 6 days, but if he gets a helper he can do it in 4 days. How long would it take the helper to paint the house alone? days Marta and Deb work together writing a book that takes them 90 days. If Sue worked alone it would take her 120 days. How long would it take Deb to write the book alone? Solve Direct Variation Problems In the following exercises, solve. If varies directly as when and find when If varies inversely as when and find when Vanessa is traveling to see her fiancé. The distance, varies directly with the speed, she drives. If she travels 258 miles driving 60 mph, how far would she travel going 70 mph? mph If the cost of a pizza varies directly with its diameter, and if an 8” diameter pizza costs ?12, how much would a 6” diameter pizza cost? The distance to stop a car varies directly with the square of its speed. It takes 200 feet to stop a car going 50 mph. How many feet would it take to stop a car going 60 mph? feet Solve Inverse Variation Problems In the following exercises, solve. If varies inversely with the square of when and find when The number of tickets for a music fundraiser varies inversely with the price of the tickets. If Madelyn has just enough money to purchase 12 tickets for ?6, how many tickets can Madelyn afford to buy if the price increased to ?8? tickets On a string instrument, the length of a string varies inversely with the frequency of its vibrations. If an 11-inch string on a violin has a frequency of 360 cycles per second, what frequency does a 12-inch string have? Solve Rational Inequalities Solve Rational Inequalities In the following exercises, solve each rational inequality and write the solution in interval notation. Solve an Inequality with Rational Functions In the following exercises, solve each rational function inequality and write the solution in interval notation Given the function, find the values of that make the function greater than or equal to 0. Given the function, find the values of that make the function less than or equal to 0. The function represents the cost to produce number of items. Find ⓐ the average cost function, ⓑ how many items should be produced so that the average cost is less than ?160. ⓐ ⓑ More than 10,000 items must be produced to keep the average cost below per item. Tillman is starting his own business by selling tacos at the beach. Accounting for the cost of his food truck and ingredients for the tacos, the function represents the cost for Tillman to produce tacos. Find ⓐ the average cost function, for Tillman’s Tacos ⓑ how many tacos should Tillman produce so that the average cost is less than ?4. Practice Test In the following exercises, simplify. In the following exercises, perform the indicated operation and simplify. In the following exercises, solve each equation. In the following exercises, solve each rational inequality and write the solution in interval notation. In the following exercises, find given and Given the function, find the values of that make the function less than or equal to 0. In the following exercises, solve. If varies directly with , and when find when If varies inversely with the square of and when find when Matheus can ride his bike for 30 miles with the wind in the same amount of time that he can go 21 miles against the wind. If the wind’s speed is 6 mph, what is Matheus’ speed on his bike? Oliver can split a truckload of logs in 8 hours, but working with his dad they can get it done in 3 hours. How long would it take Oliver’s dad working alone to split the logs? Oliver’s dad would take hours to split the logs himself. The volume of a gas in a container varies inversely with the pressure on the gas. If a container of nitrogen has a volume of 29.5 liters with 2000 psi, what is the volume if the tank has a 14.7 psi rating? Round to the nearest whole number. The cities of Dayton, Columbus, and Cincinnati form a triangle in southern Ohio. The diagram gives the map distances between these cities in inches. The actual distance from Dayton to Cincinnati is 48 miles. What is the actual distance between Dayton and Columbus? The distance between Dayton and Columbus is 64 miles. Glossary - critical point of a rational inequality - The critical point of a rational inequality is a number which makes the rational expression zero or undefined. - rational inequality - A rational inequality is an inequality that contains a rational expression.	4,717	common-pile/pressbooks_filtered	https://pressbooks.bccampus.ca/algebraintermediate/chapter/solve-rational-inequalities/	pressbooks	pressbooks-0000.json.gz:45481	https://pressbooks.bccampus.ca/algebraintermediate/chapter/solve-rational-inequalities/
X65NzZIHZRCMd_IR	Notes upon indigo / By John L. Hayes.	Article VI. — The Secretary shall have authority to loan to Members and to holders of second class stock, any work belonging to the second class, subject to the following regulations : Section 1. — No individual shall be permitted to have more than two books out at one time, without a written permission, signed by at least two members of the Library Committee ; nor shall a book be kept out more than two weeks ; but if no one has applied for it, the former borrower may renew the loan. Should any person have applied for it, the latter shall have the preference. Section 2. — A fine of ten cents per week shall be exacted for the detention of a book beyond the limited time ; and if a book be not returned within three months it shall be deemed lost, and the borrower shall, in addition to his fines, forfeit its value. Section 3. — Should any book be returned injured, the borrower shall pay for the injury, or replace the book, as the Library Committee may direct; and if one or more books, belonging to a set or sets, be lost, the borrower shall replace them or make full restitution. Article VII. — Any person removing from the Hall, without permission from the proper authorities, any book, newspaper, or other property in charge of the Library Committee, shall be reported to the Committee, who may inflict any fine not exceeding twenty-five dollars. Article VIII. — No member or holder of second class stock, whose annual contribution for the current year shall be unpaid or who is in arrears for fines, shall be entitled to the privileges of the Library or Reading Room. Article IX. — If any member or holder of second class stock, shall refuse or neglect to comply with the foregoing rules, it shall be the duty of the Secretary to report him to the Committee on the Library. Article X. — Any Member or holder of second class stock, detected in mutilating the newspapers pamphlets or books belonging to the Institute, shall be deprived of his right of membership, and the name of the offender shall be made public JOHN L. HAYES, SECRETARY OF THE NATIONAL ASSOCIATION OF WOOL MANUFACTURERS, FELLOW OF THE AMERICAN ACADEMY, AND CORRESPONDING MEMBER OF THE ACADEMY OF NATURAL SCIENCES OF PHILADELPHIA. PART I. A publication devoted to the interests of the woollen manufacture, while giving due prominence to its first raw material, wool, cannot neglect the secondary materials which enter into finished fabrics. The attractiveness and utility of the largest class of these fabrics are due to the hue given themdby the dyer ; and of all the coloring materials one of the most precious is indigo. In former times, as it still does at the East, it occupied with madder the place of one of the two most important of all dyeing materials. Forced of late years to give way to the marvellous products of modern chemistry, it will doubtless resume its place under the influence of a more enlightened economy and a more subdued taste. To contribute to the hastening of this return is one object of this essay. The most usual reproach against American fabrics is the want of stability in our dyes, — a reproach without justice, if applied to American fabrics alone ; for the cheapening of dyestuffs is practised in all the so-called manufacturing nations, and is contemned alone in the East, from which we have derived our arts, and by the people whom we despise as barbarous. To remove this reproach from American fabrics would be worthy of no little temporary sacrifice on the part of our manufacturers. The value of indigo as a dyeing material is due to the great stability of the blue color, and the derivatives from blue, which it gives to fabrics, especially of wool and cotton. It is not sufficient that a dyed fabric should preserve its color when sub- NOTES UPON INDIGO. mitted to violent tests, as when acted upon by vegetable or mineral acids or alkaline or soapy baths: the only" stable dyes are those which resist air and light, the two destructive agents of vegetable colors. Indigo, from the remarkable manner in which its color becomes fixed upon a fabric, to be hereafter explained, possesses properties of resistance and stability in a higher degree than any blue dye. And when we consider that this blue has not only its own hue, but is the best foundation for blacks, greens, purples, and even browns, the importance of these properties cannot be over-estimated. Says M. de Kseppelin, a chemist and manufacturer of Mulhouse, in one of a series of articles furnished to the Annates die genie Civil , 1864: "So high are the properties 6f resistance and stability which indigo possesses, that it is perhaps to be regretted for the art of the dyer and manufacturer of printed calicoes, that the use of indigo becomes more and more rare, and that the recent discoveries wlKBa modern science has placed at the service of industry are daily eliminating it from our factories. I have observed that whenever we have to dye stuffs of a high price, it is indigo which always serves as a base for the foundation of all the blue colors, or of those which are derived from blue. It is the same for the fabrication of printed tissues, which serve for the poorer classes, whose colors should have great stability without much increase of cost. But of late years, especially, we find a tendency to employ colors of little stability, and to prefer them, even in the class of fabrics first referred to, to those which are more fast, on account of their vivacity and freshness of tone. It is this tendency, which the consumer partakes of even while complaining of it, that the textile manufacturers ought to seek to combat. How often have I heard the greatest manufacturers of Alsace deplore the obligation which they felt that they were under of printing their tissues by means of colors so fugacious and so little resistant as those composed from aniline. We must hope, then, in the interest of that industry, that while adopting the marvellous discoveries which science is every day making, there shall be made a less general application of them, and that we shall return to the fabrication of the styles which necessitate the more constant employment of coloring materials, — less brilliant, it is true, but more adherent to the tissues, and less alterable by air and light. It seems to me, also, that taste would lose nothing; and that printed stuffs, colored in a manner less brilliant, but more harmonious, would be perhaps more appreciated, especially by those who use them." The tendency to substitute the brilliant for the stable dyes prevails too much in our own manufacture. A very considerable cloth manufacturer replied to our inquiry as to the extent to which he used indigo : " I hardly use it at all ; the dye of the indigo blue is not bright enough to be popular." On the other hand, we have heard our leading manufacturer of carpets, whose cultivated taste has led him to partake of M. de Kasppelin's views, deplore the introduction of aniline dyes, as a positive calamity to the textile industry. It is the influence of the trade, the immediate consumers of fabrics, rather thari^the judgment of manufacturers, which promotes the use of the modern fugacious dyes. The dealers desire not only to imitate the fashionable colors of European goods, but to secure the utmost cheapness. One of our largest manufacturers of woollen goods, who had made a special study of the best processes abroad, and was desirous of bringing better dyed goods into more general consumption, urged one of his largest customers, an extensive dealer, to allow him to dye the waterproof cloakings which he was furnishing for his house, in fast indigo colors, assuring him that he would charge simply the additional cost of the indigo, without profit. The offer, which involved the cost of only a few cents a yard, which would have been gladly paid by the last consumer if the difference of value had been made known, was declined. It is not improbable that the inferior goods which the manufacturer was compelled to furnish were sold to the public as fast dyed. Our manufacturers, therefore, may not have been responsible for the predicament in which the most enthusiastic defender of our protective policy found himself, as we have it from his own lips. Being about to make a speech in Congress in defence of American industries, he put on, for the first time, a coat declared to have been made of American cloth. Sitting down, heated and perspiring from the excitement of his effort, he found that beneath the arms whose gestures had enforced his eulogies of American industry, the pretended fast blue of his coat had become red, literally blushing for its unmerited praise. That fast-dyed goods of the highest excellence can be and are furnished by American manufacturers, is shown by our army cloths. The government specifications, copies of which are published elsewhere in this number, require that all the blue woollen cloth, cap cloth, and flannels furnished for the army shall be "pure indigo dyed." The requisition is strictly enforced. The admirable effect of this regulation may be witnessed at any dress parade of a battalion of United States soldiers. The persistency and uniformity of the hue under constant wear — the cloth of the common soldier in its superior dye often favorably contrasting with the finer but fancy dyed cloth of the officer — is one of the circumstances which justify the assertion, that our army is the best clothed in the world. The contrast is more remarkable still with the quondam blue cloth, converted by sun and rain into every shade of shabbiness, which we purchased in Europe for our soldiers at the commencement of our late war. ORIGIN AND EXTRACTION OF INDIGO. Indigo is a coloring material of vegetable origin, which owes its color and its important applications to a direct blue principle, known under the name of indigotine. It has been used as a dyestuff from time immemorial, by the inhabitants of India ; and it is from the East, the cradle of the textile arts, that Europe has derived it. It was probably received from India by the Greeks, among other products first made known to them by the expeditions of Alexander the Great. Dioscorides clearly refers to indigo in mentioning the two coloring matters brought from India. Pliny mentions a coloring material, having an admirable mixture of blue and purple, as coming from India, which he calls indicum. That he refers to indigo is curiously manifest by the test which he gives, by which the genuine drug might always and certainly be distinguished from the spurious. This is by putting it on live coals, when, says he, " the true indicum will burn with a flame of a most beautiful purple tint." The purple vapor from burning indigo is still a characteristic test. The Romans, it is apparent, used indigo only as a pigment, not knowing what is still the most important art connected with its use, — how to make it soluble so as to be available in dyeing. That indigo as a commercial product was first obtained from India is not only proved by the testimony of Pliny, and other ancient writers, but is confirmed by a variety of circumstances, and particularly by its name, which is known to have been nil in the Hindu language, from the earliest times of which there is mention of it. This name is still given by the Hindoos to the color blue, and to all the plants producing indigo. The Arabs and Egyptians, who obtained a knowledge of indigo from India, adopted the Hindu name, the Arabs calling it nil or nir, and the Egyptians nil or nieL The Portuguese preserved the Indian name, with a slight modification, the substance being called aniliera in their language. The coloring substances afterwards found in coal-tar having been first found in indigo, modern science has adopted for them the name of aniline. It has been asserted that this substance was not known in Europe until the time of the discovery of the passage to India round the Cape of Good Hope. But Dr. Bancroft has shown that indigo was brought by merchants from India to Alexandria, and thence to Venice, when that city was the entrepot of Europe and the East. It doubtless contributed to the excellence which the Italian states .first attained in the wool manufacture. The drug was called endigo in Venice, and it is from that city that we have derived its name and use. It was imperfectly known in England under its Spanish name in the sixteenth century, for we find in Hackluyt w Voyages " his instructions to a traveller who was going to Turkey to ascertain " if anile , that coloureth blue, be a natural commodity of those parts, and if it be composed of an herbe." in industries which it threatened to displace. These were chiefly the producers of and dealers in woad, formerly used exclusively for dyeing blue, and the corporation of woad dyers. When dyers from Italy and Flanders attempted to introduce the superior dyes of indigo, the woad interests were sufficiently powerful to induce the Elector of Saxony to denounce the use of the new dyestuflf. It was pronounced in the Diet of the Empire as " a corrosive color/' and "fit food only for the devil, " fressende teufeh. Similar propositions were made in England and France, in which latter the free use of indigo was not permitted until 1737. Although indigo as known in the arts is a product of vegetable origin, we must not omit to notice that one source of its production is the human body. It was discovered some years since that the blue color sometimes found in diseased urines, and in certain suppurations, is due to indigo. Dr. Schunck, in some papers read before the Royal Society, has shown that it is a frequent constituent of urine secreted by persons in a healthy state, and that, in fact, it is produced generally when persons do not take sufficient exercise ; and he has several times succeeded in producing it by taking in his food a rather large excess of sugar. He has found this substance also in the urine of beef cattle. It must also be observed that the chemical actions of indigotine wTith oxidizing agents, showing indigo to have a very close relation to aniline and carbolic acid, both products derived from coal-tar, have produced in the minds of chemists the conviction that indigotine, like alizarine, the coloring principle of madder, will one day be artificially produced from coal-tar. The plants which are known to furnish indigo are quite numerous, being not less than sixty ; they do not all belong to the same family, and none of them contain the coloring principle already formed. The most important belong to the leguminous family, from which most of the vegetable dyes are derived, and to the genus indigofera. The species cultivated and most esteemed are Indigofera tinctoria, I. disperma, I. anil, I. argentea. The principal source of the indigo of commerce is the Indigofera tinctoria. The accompanying figure is a correct representation of the plant, and we may dispense with a description of its botanical characters, observing only that the plant has a half woody stem, and rises to the height of from three to five feet. The plants exhale a strong odor towards evening in the fields where they are cultivated. The leaves have a disagreeable taste, and rapidly putrefy in water. The plant originated in Campaja, or Guzerat, but is cultivated in Hindostan, China, Java, and in the East Indies generally. It was carried by the Spaniards to South America and the West Indies, and it can be acclimated in all hot countries. The Indigo fera ar gen-tea, or indigo-plant of Egypt, furnishes the indigo produced in that country and Arabia. The culture of the plant and the production of commercial indigo is carried on on a vast scale in Lower Bengal. We have before us a large map, placed at our disposal by an India merchant of Boston, showing the location of each of the hundreds of factories of that important centre of production. These factories have been developed by British enterprise ; and India thus receives some slight compensation for the ruin of her cotton manufacture by the same influence. The propagation of the indigo-plant in that country is made by sowing in a thoroughly tilled silico-argillaceous soil. The seed of the plant is sowed annually in the spring or autumn, according to the variety used, some germinating more slowly, and requiring to remain in the ground longer than others. The time of putting in the seed is also governed by the nature of the soil and its position in respect to neighboring rivers. In the lowlands subject to inundations, the indigo ought to be all cut at the period of the rains and inundations, which would destroy the crop in a brief time. Besides, during the rainy period the planter has at his disposal sufficient water to commence his operations of fabricating the indigo, which is the suitable^ time for beginning the cutting of the plant. The time of cutting the indigo-plants is therefore regulated by the elevation of the land and danger from floods. The high lands are always sowed several weeks after those subject to inundations. The Chinese prick out the young plants in parallel rows, always preserving the land quite clear of weeds. By taking away the blossoms of the plant before their development, they increase the growth of the leaves, and, consequently, the return .of indigo ; for it is in the leaves principally that the coloring material is found. In certain localities the planters break off the leaves which have acquired a bluish green tint. But more frequently the whole plant is cut down close to the ground in the months of June or July, when the flowers begin to open. The portion of the plant which remains pushes up quite rapidly, and furnishes a second, and even third, and sometimes, though rarely, a fourth cutting. The quality of the product diminishes according to the number of the cuttings. The plant called nil9 cut down to the root and gathered up in packages, is worked up the same evening. The package is formed from the product of a space of land embraced by a chain about three yards long. The value of the first material changes with the value of the soil. Thus, one soil produces a plant which has many stems and few leaves, while another gives many leaves and few stems. The richness in coloring material depends upon the quantity of leaves, but varies also with an equal weight of leaves with atmospheric influences. Thus regular dealers in the article observe a marked difference in the quality of indigo in different seasons. M. A. Koechlin Schwartz has recently published some interesting notes upon the preparation of indigo in Lower Bengal. In that country, which furnishes excellent indigo, the factory includes, besides filters, presses, a steam-engine, drying apparatus, and reservoir of water, two lines of vats, arranged one above the other, from fifteen to twenty in each line. These vats are built up with bricks, and covered with a strong coat of solid and well made stucco. They are square, about six yards on a side, and about a yard deep. The back row is about a yard above the front one. The plant is fermented in the vats of the upper row ; when the operation of fermentation is terminated, a faucet is opened, and the liquid is run into the lower vat. The water of the Ganges, which is relatively pure, and thus well suited for this work, is brought into basins of deposition, where it becomes clarified, and is distributed by a common canal to the vats of the upper row. The plants, cut in the morning and bound up into packages, come to the factory after midday, and are thrown into the vat in the evening. A vat contains one hundred packages carefully arranged, one beside the other ; heavy timbers are placed upon the plants, which are pressed down by means of large wedges. It is necessary that the plants should be pressed together very compactly, as without this the fermentation does not take place to advantage. At nightfall the water is introduced into the vats, and fills them so as completely to submerge the plants. The fermentation is more or less prolonged according to the temperature. Its duration varies from nine to fourteen hours. The workmen judge as to the procedure of the operation by withdrawing a little of the liquid in the lower vat. If it is of a clear pale yellow when withdrawn, it will furnish a product less abundant but more pure than if of a deep gold color. At the moment of its issue from the fermenting vat the liquid is of a yellow color, more or less deep. The liquid is allowed to remain undisturbed for a brief period, when twelve naked men, armed with long bamboos, enter the vat to beat the water while it is still warm. During this time the upper vat is emptied and cleaned out for the succeeding operation. One vat requires seventeen workpeople (twelve men and five women). They thrash the water for two or three hours. The liquid passes by little and little to a pale green, and the indigo is found on suspension in the form of small floccules. The liquor is suffered to remain undisturbed for half an hour ; it is then gradually decanted by opening, one after the other, the discharging holes placed at different heights. The water returns to the river, and the precipitate, under the form of a thin bouille, is turned into a reservoir. This bouille is pumped up into a vessel, and made to boil for a moment to prevent a second fermentation, which would injure the quality of the product, by turning it black. It is suffered to rest about twenty hours, and the next morning it is again subjected to boiling, the ebullition being kept up three or four hours. The boiling deposit is then turned off upon a large filter, through which the water drips. This filter is composed of a vat constructed of masonry, covered with stucco, about eighteen feet long by six feet wide and three feet deep. This is covered with bamboos, upon which is a grating of smaller reeds, and above by a stout strained cloth. The water which is run into the vat deposits some indigo which has pressed through the filter. This is decanted after being allowed to rest, and the turbid liquid is boiled the next day with the fresh indigo. The paste of the filter is introduced into some small boxes of wood, pierced with holes, and provided above and below with a strong cotton cloth. The whole is again covered with a piece of stuff, and then with a covering of wood, pierced with small holes, and it is placed under a press, the force being gradually applied, so as to cause the water to run out as much as possible. There is withdrawn from the box a cake of the size of a cake of Marseilles soap. The water squeezed out flows back into the filtering vat, to be boiled again with the fresh indigo. The drying of the cakes ought to be done very slowly. The dry-house is a large building of masonry, quite high, and pierced with many openings, provided with narrow blinds, to prevent the direct light of the sun from penetrating into the in- terior. Cure is taken also to surround the dry-house with large shade-trees. The cakes take from three to four days to dry, after which they are packed in small boxes and carried to Calcutta, the great market of Bengal. The details above given apply to the factories managed by European planters. The natives operate in nearly the same manner, but with less care, and consequently their products are inferior. The average product of indigo in Lower Bengal is stated at 4,000,000 kilograms, or 8,840,000 pounds per year. The most remarkable fact to be noticed in these operations is, that the blue principle is developed by chemical action from certain absolutely colorless principles existing in the plant. The theory of the change effected is still somewhat in doubt, because no chemist has studied the fresh plant, and observed upon the spot the phases of the operation of the production of indigo on a large scale. But the most accepted theory is that derived from the researches of Dr. Schunck, upon the isatis or woad-plant, which produces indigotine in a much less degree than the true indigo-plants ; viz., that the indigo exists in the plants combined with sugar, forming a glucoside, to which he gives the name indictm. This compound, under the influence of fermentation in the manufacturing process, is supposed to be unfolded into indigo and sugar. Without dwelling upon this question, which is beyond our province, we observe that the plants of the genus indigofera are used for the production of commercial indigo, on account of the greater richness in the coloring principle. Other plants, which furnish the same coloring principle, indigotine, are more frequently used directly in dyeing to furnish the blue principle than they are for the production of indigo. The most important of these plants, although there are others, such as the Polygonum tinctorium and the Nerium tinctorium, is the Isatis tinctoria, which produces pastel, or woad. This plant belongs to the family Qf crucifera3, and is a biennial. It is represented in the accompanying figure. The leaves which surround the stem are collected in May or June of the second year, when they begin to turn yellow. The wasted and dried leaves are sometimes used directly for dyeing, but more generally the leaves, after being cut and dried, are carried to a mill, and then ground to a paste, after which it is formed into a mass or heap, and being covered to protect it from rain, is left to undergo a partial fermentation for about a fortnight. The heap is then well mixed and formed into balls, which are exposed to the sun and wind to dry, and thereby prevent the putrefaction which would otherwise take place. Being afterwards collected in heaps, these balls again ferment, become hot, and emit the odor of ammonia, which Hume tells us, in the History of England, gave such offence to Queen Elizabeth that she issued an edict to prohibit the cultivation of this plant. After the heat has continued for some time, these balls fall into a dry powder, in which form the woad is usually sold to the dyer. The best French woad comes from Provence, Languedoc, and Normandy. In Germany, the pastel of Thuringia is used almost exclusively ; the packages have the trade-mark of three towers, with the numbers 4, 5. In this country, owing probably to the prejudices of practical dyers, who have generally come from England, the Lancashire woad is almost exclusively used. The very little imported of late years, ranging from two thousand to twelve thousand dollars annually in value, is used for mixing with tindigo in the so-called woad vat, to be hereafter described. COMMERCIAL INDIGOES. The following description of the indigoes of commerce is taken principally from Schutzenberger's excellent treatise on coloring materials. It coincides very nearly with that given by Napier from Dumas and Chevrueil. Indigoes are classed, according to their origin, into three groups. and Guatemala. Indigoes of Java. — These are distinguished by the great purity of their coloring material. They contain the minimum of extractive organic matter. If, in spite of this, they do not give a high yield of indigotine ; this is owing to a mixture of silicious mineral substances with their paste. The paste is soft. It adheres strongly to the tongue, and its density is feeble. They are generally of a pure blue, light or ash colored in the kinds which are less rich, and of a magnificent violet blue in the superior qualities. The last take a beautiful copper color when scratched by the nail. They are placed in the very first rank among all indigoes in respect to fineness and beauty, if not in richness in the blue coloring principle. Their purity, complete absence from carbonate of lime, and the small quantity of foreign organic materials which they contain, cause them to be much sought for, for the preparation of carmine of indigo. The consumption of the Javan indigoes in this country is so small as not to be appreciated. Bengal Indigoes. — These are the indigoes par excellence, for in them are found the most varied qualities, from the most beautiful and rich to the most ordinary. The superior qualities are of a deep violet blue, with a fine and uniform paste ; they adhere to the tongue, are easily pulverized, and take a beautiful coppery tint when scratched by /the nail. The fresh fracture shows a magnificent purplish blue reflection. Their yield in# indigotine does not surpass seventy-two per cent. After these come the reddish violet indigoes with a purplish hue, and a fracture more uniform and shiny. They are also more dense and hard than the superior qualities. The reddish hue does not proceed from the greater or less amount of coloring material contained, but from the presencp of a greater quantity of brown and red extractive matter. These qualities are not to be despised, for the kinds which give the best results in the dyeing vat are found in these indigoes. It would seem, in fact, says the author whom we are following, " that the browns and reds of indigo play an important part in vat dyeing, that they are able to become dissolved and to fix themselves upon the tissues at the same time as the indigotine, and thus operate to reinforce the hue. The fact is,#that dyers generally prefer the reddish indigoes to the other varieties." Among the Bengal indigoes there is found a clear blue variety, less rich in coloring matter, but also more exempt from organic substances. The impurity is constituted by mineral matters. It is less dense, adheres strongly to the tongue, and does not take a coppery hue, like the other varieties, when scratched by the nail. The worst qualities of the Bengal indigoes, as in all the species, are the clear blues, shading on to gray or green. This coloration denotes a great quantity of extractive matter different from the indigo brown which characterizes the red varieties, and completely inert. These indigoes are hard, dense, adhere little or none to the tongue, and do not show coppery reflections when scratched. The most skilful connoisseurs distinguish forty-three varieties of Bengal indigo. The most important are the following : — 1. Superfine blue, light or floating. — Color bright blue; pery, and low coppery. The Indigoes of Oude and Coromandel. — These are made in the interior of Hindostan. Those of the best quality correspond to the middling Bengal indigoes, and are met with in square masses, having an even fracture, but are more difficult to break ; the inferior qualities are heavy, of a sandy feel, having a blue color, bordering on green or gray, or even black ; often in large squares, and covered with a slight crust or rind of a greenish color. They are the most difficult to break of all the indigoes of commerce. Madras Indigoes. — They have a grained fracture, and are of a cubical figure. The superior qualities have no rind. The qualities are fine blue, mixed violet blue, and ordinary. They are all lighter, and less rich in coloring-matter than the Bengal indigoes. Manilla Indigoes. — These occur in cubical blocks, flat squares, or in irregular pieces. They are light, with a fine paste, and of a clear blue. They effervesce with acids, showing the presence of carbonate of lime incorporated in their paste. They are consequently poor in coloring material, and are hence almost exclusively used as a bluing material in washing fabrics. American Indigoes. Guatemala, — These indigoes are produced now altogether in Hunduras, although they still retain in commerce the name of Guatemalan. They are generally found in small pieces, irregular in form and size, and come in envelopes of skin containing about half as much as the Bengal chests. Putting aside the difference in exterior form, these indigoes approach very closely to those of Bengal. The same qualities are found, only they are more frequently mixed. The clear blue is more rare, and, when it is found, it is poorer in coloring matter. In purchasing these indigoes it is necessary to beware of the reds, which often contain a strong proportion of the brown extractive matter. It is not rare to find among the Guatemalan indigoes beautiful specimens of the blue violet, equal to the richest Bengal variety. Unfortunately, this superior variety is generally mixed with inferior kinds, as to have less value. The American indigoes are classified as follows : — heavier, coppery red. Caraccas. — These resemble very much the Guatemala varieties. The qualities are designated by analogous names, but they are, in general, less esteemed than the preceding. raccas and Mexican. Brazil. — These indigoes are in small rectangular parallelopiped masses, or in irregular lumps of a greenish gray color externally, and having a smooth fracture, a firm consistency, and a copper-colored tint of greater or less brilliancy. The indigoes of Africa and Egypt. — These have only been manufactured within the last twenty years ; they are in flat squares. The paste is fine and quite light, and the color pure blue or bordering on violet. The varieties are distinguished as fine blue and good violet and red. merce, but of good quality. The indigoes of the inferior qualities, characterized by a saltlike color, bordering more or less upon green ; by a coarse, uneven, and very dense paste ; by not adhering to the tongue, and by not showing a coppery color when scratched, — can never be employed to advantage, notwithstanding their low price. The purchaser of these qualities must be guided solely by the results of analysis ; for an article is found in commerce whose richness in indigotine does not exceed twelve to fourteen per cent. The presence of so high a proportion of foreign matter prevents the chemical change which the indigo ou^ht to undergo in the dyeing vat ; and this foreign matter, added to the deposits of the dyeing vats, causes great loss of the coloring matter. These indigoes should be used as little as possible, especially in the cold vats used for dyeing cotton and linen. The middle varieties of the Bengal and Guatemala indigoes, and, above all, the red varieties, produce in the cold vats the most advantageous results. The lower qualities above spoken of present less inconvenience in the hot vats used for dyeing wool ; and it is for this purpose that they are generally used. In considering the previous observations, the wool manufacturer may arrive at this conclusion : that while he can, with less loss than the maker of cotton fabrics, make use of the lowest qualities of indigo, he will obtain the best results from the middle qualities of the reddish Bengal indigoes. The skilled dealers in indigo recognize not only the above distinctions, founded upon the country of production, color, and physical qualities, but they observe whether the article has any of the following defects, which are designated by certain well-understood terms : such as whether the indigo is sandy, — when brilliant points are observed in the interior, which are in reality particles of sand ; spotted, that is to say, of unequal tint, and marked by small blackish points ; ribboned, marked by transversal bands of a paler, and sometimes red color ; burnt, the pieces having a scorched appearance, due to rapid drying, and separating into small black fragments under the pressure of the hand ; crumbly, when in pieces of irregular figure, proceeding from fractures of the squares ; cold, when the indigo does not adhere to the tongue. The above classification is presented with a full knowledge that these distinctions are by no means recognized in the ordinary commerce in this article. It is not, however, without interest as an illustration of the minute attention given to this subject in Europe, where a higher manufacture requires a nicer investigation of the qualities of materials employed. DETERMINATION OF THE RICHNESS AND PURITY OF INDIGOES. It is evident that the commercial form and the high price of this drug favor fraud, and the desire to illicitly introduce foreign substances into the paste. It is important, therefore, that the purchaser should carefully ascertain the actual value of the article wThich he is to use. He should know not only the proportion of indigotine contained, which varies in the commercial indigoes from twelve to seventy-five per cent, but the hardness and density. A good indigo ought to have qualities wrhich can be recognized by the eye and touch alone. The first and the only examination ordinarily made by purchasers is in respect to the physical qualities of the article. Different pieces are selected, and their fresh fracture is attentively observed. The purchaser observes whether the squares are like each other, and if the parts of the same piece present the same tint. He determines the porosity by the simple means of applying his tongue to the fresh fracture. The more rapid the adherence of the tongue, the more porous the indigo. By scratching the piece with his finger-nail, he determines the extent of the coppery reflection, — an important test. From all these characters, taken together, the purchaser can form quite a correct idea of the value of indigoes in general ; and the greater number of dyers, both in Europe and this country, are satisfied to make their purchases with only this physical examination. The most experienced dealers in this country make no other examination than the physical one. An eminent indigo broker in Boston has permitted me to copy the following memoranda for the physical examination of indigo from his notebook. The chief signs of good indigo are its lightness, feeling dry when touched, and, when broken, appearing ®f a beautiful violet blue. Good indigo swims in water ; if thrown upon burning coals it emits a violet-colored smoke, and leaves but little ashes. In selecting indigo the large regularly formed cakes should be preferred, — those of a fine, rich blue color, extremely free from the white adhesive mould,* and of a clean, neat shape. When broken, it should be of a bright purple cast, of a close and compact texture, free from specks or sand, and when rubbed with the nail should have a beautiful shiny coppery appearance ; when burnt in a candle it should fly like dust ; that which is heavy and dull colored should be rejected. Indigo is estimated and classed in commercial language, as follows : fine blue, ordinary blue, fine purple, inferior purple, and violet, strong copper, and ordinary copper. It is purchased by the factory maund (74\| lbs. The Bazaar maund is 82^ lbs.), packed in cases containing on an average 2\| cwt., dammered (pitched) and covered with gunny bagging. Still, in making large purchases, as a measure of wise precaution the chemical test should be added. This is used to ascertain the proportion per cent of indigotine which a given indigo has. The determination of the quality of indigotine contained is not alone sufficient to- fix the value of an indigo. With an equal yield of indigotine, the indigoes are always to be preferred which have a light and soft paste ; and for the preparation of the indigo vat the preference should be always given to the violet red rather than to the clear blue indigoes. The chemical works which treat of this subject give elaborate details of a great number of processes for determining by chemical tests the amount of indigotine, or the coloring material in indigoes. To give these numerous processes would only confuse the reader. In our own confusion upon this subject we submitted the descriptions of these various processes to one of the most eminent and practical of American chemists, Dr. Charles T. Jackson, an official State Assayer for the State of Massachusetts, who has had much experience in testing indigo, with a request that he would describe the process which he approves and practises. He has obliged us by the following communication : — Dear Sir, — In reply to your inquiry as to the simplest method of analyzing indigo, I would say that I first ascertain the amount per cent of earthy matters and metallic oxides, in the samples brought to me, by burning a weighed quantity in a counterpoised platinum crucible, until all organic matters are removed or consumed, and then weighing the ashes obtained. The ash is then subjected to analysis in the usual way, and lime, alumina, peroxide of iron, and some other earthy impurities are separated. Then, to determine the amount of coloring matter, or indigotine, I make use of a standard sample of pure reduced indigo, which is dissolved in the most concentrated sulphuric acid, and diluted with water after solution. Then I ascertain how much bleaching powder (chloride of lime) is required to dissolve the solution. This is the quantity required for absolutely pure indigo. Now, the indigo of commerce does not contain more than say from forty or fifty per cent of pure indigotine, and of course will require a smaller quantity of bleaching powder to decolor it; or the quantity of bleaching powder to decolor a given weight of pure indigo may be weighed out, and the sample to be compared having been dissolved in strong sulphuric acid, and diluted with water, is to be poured in and stirred or shaken well until the point of decoloration is ascertained. In this case it is best to weigh out at least twice as much of the sample to be tested as was used of pure indigo, and to measure the solution in a graduated glass vessel, — an alkalimeter, for example,— so that by measure we may know exactly how much of the sample we add to the solution of bleaching powder. Thus the relative coloring values of the samples may be readily ascertained. parative trial of your samples against a perfectly good sample of Bengal indigo, which may be kept for a standard of comparison. Very useful practical results may thus be obtained. It is well, however, to keep on hand a standard sample of pure indigo, prepared from reduced or white indigo, as directed by Berzelius (vol. vi. page 3, French ed., 1832), and in Muspratt's Chemistry applied to the Arts (Dyeing, Indigo). In the analysis by reduction of indigo, the process is simply as follows : Reduce the indigo to fine powder, and weigh it ; weigh out an equal quantity of pure quicklime (made from pure white marble)* Measure in a graduated vessel a certain volume of water. Slack the lime with a portion of this water. The rest of this water is to be used in rubbing up the indigo in a mortar. Then the slacked lime is to be mixed with the indigo, rubbing the substances well together. Introduce the whole into a large flask ; 1 J to 2 litres (about 3 to 4 \ pints) of water is required for 1 gramme (or about 15 grains of indigo). The flask and contents are then to be exposed to a heat of from 176° to 190° F. for some hours. This is best effected in a water bath. By this digestion the lime is made to combine with the indigo brown, and the coloring matter is set at liberty. Dissolve in the liquor a little protosulphate of iron, exempt from copper, and reduced to a fine powder. The flask is to be corked and well shaken, and allowed to cool. When the sediment is settled, decant the clear solution by means of a syphon into a graduated glass. The coloring matter oxidizes by exposure to the air ; and to favor this oxidation and to keep the lime in solution, add muriatic acid to the liquor. When the liquor has become clear, filter and collect the precipitate on a weighed filter, which wash with hot water, and dry at a temperature of 212° F. Thus we can learn, by weighing the filter again, how much indigotine is contained in the sample. If we make use of 200 measures of water, and have drawn off 50 measures of the solution to oxidate, and this 50 measures has produced 10 grains of indigo, the whole sample evidently contained 40 grains of indigo blue. This method serves both for an assay of the sample and the production of a standard sample of pure indigotine. The operation may be carried on upon a larger scale for the manufacture of a standard sample. In the processes given I have not referred to the qualitative analysis or testing for all the kinds of adulterations, but have given only valuation of the coloring power of indigo. I have had occasion to search indigo for Prussian blue, an occasional adulterant. This is ascertained by caustic potash, which becomes in part an oxide if Prussian blue is present. This acidulates with muriatic acid, and, tested with sulphate of iron, proves, by formation of Prussian blue, the presence of the ferrocyanide of potash in the solution, and hence Prussian blue in the indigo. Lime and clay are the usual adulterants, and oxide of iron is often present accidentally or from the clay adulterants. Starch and flour are rarely used, as they add little to the weight. Before proceeding to a consideration of the practical applications of indigo in manufacturing, we must pause to make some general observations upon the commerce in indigo. The first European impulse given to this commerce was made by the Spanish and Portuguese. They not only imported indigo from the Indies, but established its fabrication in their colonies. To them we owe its production in Guatemala, Caraccas, and Brazil. The French exported from the Island of San Domingo, only, in 1774, 2,350,000 pounds weight of this commodity. British influence was exerted in favor of the development of this article in the American colonies, and, in 1773, in the space of twelve months, over a million pounds of indigo were exported from South Carolina. The production in India wTas at that time of little importance. It was not until 1783 that the attention of the English was directed to the culture of indigo in India for European consumption, that produced by the natives being all consumed in their own manufactures. In the hands of the English this product rapidly rose to be the most important of India, in a commercial view, except that of rice. The small cost of a factory, and the comparatively small capital required for this production, caused the indigo culture to be preferred to sugar planting. The importation and sale of this commodity at the East India House, in 1792, amounted to 581,827 lbs., while the importation into Great Britain from other parts of the world amounted to 1,285,927 lbs. In 1806 the importation from the East Indies, and sales at the East India House, amounted to 4,811,700 lbs., and produced in sterling money £1,685,275. In the year 1862-63, the export from India, and the destination of supplies, were as follows: — - The value of exports in 1866 was £1,861,501. In the same year the imports of indigo from the whole of Central America, including Honduras, was 672,480 lbs. The consumption of indigo in Great Britain did not increase during the ten years ending with 1867. This stationary demand, notwithstanding the fall in the price of the drug and increase of population, is attributed by McCulloch principally to the decreasing use of blue cloth. It is more probably due to the substitution of cheaper dyes. The average home consumption in Great Britain for seven years ending in 1867, was 1,675,072 lbs. per year. The importation into this country for the twenty years last past is shown by the following table, kindly prepared at our request by the chief of the Bureau of Statistics : — Bureau of Statistics, Nov. 16, 1872. The extraordinary quantity imported in 1862, we hardly need remark, was due to the demand for consumption in army cloths. Indigo imported directly, was made free of duty in 1861. The duty which appears by the above table to have been charged since that period, was upon indigo, the product of India, imported by way of England, which was subject t6 an extra duty of ten per cent. The indigo consumed in the United States is generally supplied by the Boston and New York Calcutta houses, who have either an American partner resident in Calcutta, or who employ a resident American as agent. Indigo, like other Calcutta goods, is sold through the agency of brokers, who receive on this article a commission of one per cent. The value of the article is known almost daily in these cities by telegrams, giving exact information of the state of the trade, transmitted from Calcutta as often as every five days. Some of the brokers publish monthly circulars, showing the stock of indigo with other Calcutta goods on hand in our market. The regular trade reports issued by the India merchants show that the higher qualities of indiw do not come to our market. The following is an extract from a report of Whitney, Brother, &Co., of 1871 : — At the present moment there is great depression in the trade in this article. The last telegrams show a decline of price in the Indian trade in this article of from fifty to seventy-five per cent from the prices of last year ; and the apprehension is even entertained that indigo is going out of use, the dreaded competitors being the aniline dyes, and particularly the Nicholson blue. We maybe presumptuous in giving our opinion on the question, but we hazard the prediction that, notwithstanding the temporary popularity of the cheap substitutes, a reaction will take place in favor of that " wonderful and most valuable production," whose importance as a dye has been held in India for thousands of years and Europe for two centuries, "greatly to exceed any other." * * The " Dictionnaire Universel du Commerce," &c, published in 1861, contains an exhaustive article on the commerce in indigo, by M. S. Beekrode. From the statements of this writer, it appears that the consumption of indigo was estimated, in 1835, FORMER PRODUCTION IN THE CAROLINAS. As pertinent to the commercial branch of our subject, we must briefly notice the remarkable facts of the sudden growth and equally sudden and extraordinary extinction of the production of indigo in the Carolinas. Indigo was for many years the second great staple of South Carolina. So highly was this staple estimated that the historian of the State declares that " it proved more really beneficial to Carolina than the mines of Mexico or Peru are or ever have been to Old or New Spain." Its introduction was the happy result of a woman's culture and energy. In the early part of the last century, the indigo plant had been extensively cultivated in the West India Islands, which then furnished the chief supply of Europe. The governor of Antigua, George Lucas, whose home plantation was at Wappoo in Carolina, having observed the fondness of his daughter, Miss Eliza Lucas, afterwards the mother of General Charles Cotes worth Pinckney, for the culture of plants, was in the habit of sending to her tropical seeds to be sowed on his plantation at Wappoo. Among others, he sent her some seeds of the indigo plant cultivated in the West Indies. She planted them for two years ; but As the maximum annual consumption in 1859 is setdown at 5,000,000 kilograms, the author concludes that the average production at that time did not surpass the requirements of the dyers of the whole world. the seeds failed to germinate, or were killed by the frost. On the third year's trial, in 1741 or 1742, she was successful. Governor Lucas, on hearing that the plants had ripened and produced seed, sent from Montserrat a person skilled in making indigo. Vats were built on Wappoo Creek, and there the first American indigo was manufactured. The attempts of the expert to conceal his processes were defeated by the vigilance of Miss Lucas. The process of manufacture was made known. Seeds from the AYappoo plantation were freely distributed and successfully planted ; and the culture of indigo became common. In 1747, a considerable quantity of indigo was sent to England, which induced the merchants trading with Carolina to petition parliament for a bounty on Carolina indigo. In 1748, an act of parliament was passed granting a bounty of sixpence per pound on indigo raised on British-American plantations and imported directly to Britain from its place of growth. This' act stimulated the planters of Carolina to double vigor in the production of this new material for export. " Many of them," says Dr. Ramsay, "doubled their capital every three or four years by planting indigo." In the year 1754, the export of indigo from the province amounted to 216,924 lbs., and in the years 1772 and 1773 the export had risen to 1,107,661 lbs. The production was greatly checked by the war of the Revolution. Near the close of the century the large importations from India lowered the price, so as to make the planting unprofitable. In the mean time, the culture of cotton had sprung up under the protective tariff of 1789. The grounds suitable for indigo planting were equally fitted for cotton, and were for the most planted with the new staple. It is curious to observe how the former was displaced by the latter staple. The export of indigo from Charleston in 1797 was 96,121 lbs. : in 1800, it fell to 3,400 lbs. During the same years, the exports of cotton rose from one million to six and a half million pounds. The production of American indigo appears to have revived from time to time up to 1829. A writer of that period in Silliman's Journal of Science estimates— although it would seem on doubtful authority — the production of indigo in the United States at 20,000 lbs. The price of the American article had fallen, owing to the great quantity of extractive which it contained, to fifty cents per pound, while the Bengal indigo was worth $1.15 per pound. We have no data as to its production at the present time, but infer, from the fact that no reference has been made to this product in the Government Agricultural Reports for many years past, that the production, if any, is too unimportant to be noticed. INDUSTRIAL APPLICATION OF INDIGO. All the applications of indigo require that the material should first be reduced to an impalpable powder. It is better to grind it with water, to prevent the loss of material in the form of powder, although the dry pulverization is necessary when the indigo is to be used for the manufacture of the sulphate. To facilitate the grinding the material into a paste, it should be previously soaked in hot water from one to three hours. The grinding on a small scale may be done by a very simple apparatus. This is a hemispherical vessel of copper or cast-iron, eighteen inches in diameter, furnished at the edge with two handies. The workman, sitting astride a bench, places the vessel before him, in which he places three heavy cast-iron balls, the indigo which has been softened, and a sufficient quantity of water. Holding the basin by the handles, he gives it a circular oscillatory movement, in such a manner that the balls, following this mover ment, crush the indigo which surrounds them ; after which the contents are poured into another vessel, water is added, and the material is stirred. The portions incompletely ground are made to reunite themselves at the bottom by means of regular blows with a hammer on the rim of the vessel. The upper liquid is decanted, and the deposit is submitted to a new manipulation in the basin. In large establishments the grinding is done by machinery. An apparatus highly recommended, consists of two circular plates of cast-iron, arranged horizontally and slightly separated, one from the other, which are rapidly rotated by power, in inverse, directions. The interior surfaces of these disks are provided with deep grooves radiating in a curved line from the centre to the circumference, and diminishing in depth in the same direction. The indigo which has been previously softened enters between the two plates by an opening in the centre of the upper one, and escapes in a thin paste by the circumference. The application of indigo to the coloring of textile fabrics requires the complete dissolving of the substance, for which the mechanical division is only a preliminary. There are only two known means of dissolving this substance: 1. By reduction; 2. By the action of concentrated sulphuric acid. The first means allows indigotine to be regenerated ; and, when the dyeing is completed, it is pure indigotine which adheres to the colored fibre. By the second means, or dissolving by sulphuric acid, the coloring material enters into a new combination, from which it can never be separated : it becomes a new substance, endowed with new and special properties. The fixing of Indigotine by means of Reduction. — In this method the operator avails himself of one qf the most remarkable qualities of indigotine : this is the facility with wrhich this body takes up hydrogen, and becomes transformed into a colorless substance, wrhich is soluble in favor of alkaline or alkalineearthy bases, and is susceptible of reproducing indigotine by simple oxidation in contact with air. This hydrogenized substance is called white indigo. Blue indigo, or indigotine, is insoluble except by concentrated sulphuric acid ; and this insolubility gives it its superiority to all other blue dyes. Not being soluble, it cannot, as blue indigo, attach itself to the material to be dyed ; but in the soluble form of white indigo it can perfectly penetrate the fibre. If by any means of oxidation we can transform the white indigo into blie indigotine, the latter becomes insoluble, and is imprisoned in the pores of the fibre. This is, briefly, the whole theory of the use of indigo in dyeing or printing, although the reaction may be applied in different ways to the coloring of fibres, such as — 3. The white indigo is precipitated under the form of a paste, in combination with a metallic oxide having strong reducing power, such as hydrated protoxide of tin, which prevents the too rapid reoxidation of the indigotine. The thickened paste is printed, and the tissue is placed in an alkaline bath (lime or soda), which, displacing the oxide of tin, forms a soluble combination of white indigo. The latter can then penetrate the fibre, and afterwards become fixed by reoxidation. This is the printer's solid blue. 4. The finely ground, but not dissolved indigo, is placed upon the tissue in such conditions that it can be dissolved and reduced in place. This done, the fixing of the indigotine is effected by oxidation. This is the method for China blue or bleu faience. v DYEING BY THE INDIGO VAT. The Copperas Vat. — For dyeing cotton, the method of reduction found by experience to be the most convenient and practical is founded upon the action of the hydrate of the protoxide of iron in the presence of lime. The hydrated protoxide of iron is obtained from sulphate of iron (green vitriol, or copperas) with freshly burned lime. Certain precautions should be observed in the use of these materials. The copperas used for the preparation of these vats should be free from sulphate of copper, because jhe oxide of copper which would be formed in the vats rapidly oxidizes the reduced indigo, and causes its precipitation in the bath. The copperas ought not to contain red oxide of iron, nor sulphate of alumina.' The coppery or oxidized vitriol may be purified by boiling the solution with pieces of iron, which precipitates the iron and neutralizes the oxide. The lime ought to be pure, containing no magnesia ; when slacked lime has been exposed to the air, even for a short time, it absorbs carbonic acid, and becomes converted into chalk. The lime, therefore, should always be newly slacked. The ingredients, then, of a copperas vat are water, pure or purified green vitriol, indigo ground into a homogeneous impalpable paste, and pure and freshly slacked lime. The proportions used in different establishments are exceedingly variable. Those which answer for a laboratory vat, or a small vat used for precipitating the white indigo immediately for printing, are: indigo, one part; sulphate of iron, two parts ; slacked lime, three parts. These proportions are not enough for the large vats used in dyeing pieces. In them it is necessary to make the quantities of lime and sulphate of iron larger than the theory of the vat requires. The excess of lime and hydrate of iron serve the purpose, whenever the vat is stirred, to repair the losses of indigo caused by its oxidation from contact with the air. Schutzenberger gives the proportions generally used by the dyers of France, as follows : — M. de Kseppelin, who is especially familiar with the cotton dyeing in Mulhouse, describes the ordinary vats for cotton dyeing as bound with iron, and placed on the level of the ground. They hold from 3,000 to 4,000 litres (1,055 gallons) of liquid. In preparing them the dyer fills them about three-quarters full of water, and pours in a milk of lime, prepared with 45 kilograms (100 lbs.) of freshly slacked lime ; a fine liquid paste having been previously made from 15 kilograms (33 lbs.) ground in water. This is added to the lime in the vat by portions, the liquid in the vat being stirred up by a rake after each portion of the indigo paste has been added. The indigo becomes dissolved in about twentyfour hours, when the vat can be used. After describing the manner in which the frame, or champignon, containing the goods to be dyed is arranged and immersed in the vat, this author continues : w It will be understood that the vat is composed according to the degree of intensity of the color which is sought to be obtained, and that hues more or less deep may be obtained by means of more or fewer repeated immersions of the fabric to be dyed. After each immersion the champignon is lifted out of the vat, and the fabrics are left to ungreen themselves by contact with the air. (It must be observed that, although soluble indigo is called white, because it is without color when carefully prepared in the laboratory, the goods, when first taken from the ordinary vat, are of a green color.) Exposed to the air, the soluble indigo is precipitated in the state of blue indigo upon the fibres of the tissue. This oxidation, or dehydryzation, may be hastened by plunging the tissue into a vat containing a solution, very much diluted with water, chloride of lime, bichromate of potash, or sulphuric acid. The first two act as oxidizing agents ; the last facilitates the restoring of the blue indigo by depriving it of the lime which is in excess in the solution of indigo which the tissue has imbibed from the vat." He adds further : " To facilitate the formation of blue indigo in the interior of the fabrics, the stuff to be dyed may be pre-' viously impregnated by a saline solution, which has the property of precipitating the white indigo from the alkaline solution, and of fixing itself more rapidly upon the tissue. Oxide of copper and oxide of manganese possess these properties in a high degree, and are used in many establishments to hasten the dyeing process, and produce an economy in raw materials. The pieces of cloth are placed in a solution of sulphate of copper, in the proportion of 15 to 20 grams to the litre (2.11 pints), and lightly thickened with starch. The fabrics, thus impregnated by a kind of mordant, before receiving the blue dye are first passed through a weak bath of milk of lime, which fixes the oxide of copper upon the tissue. The blues thus obtained are more intense, and have a peculiar lustre. This process is used in Austria and Germany, where cotton fabrics are printed on both sides of the tissue." his recent lectures before the Society of Arts, speaking of the cold vat for dyeing cotton, says: "The oldest, and still most generally employed method of preparing cold vats, consists of putting into a vat containing about 2000 gallons of water CO lbs. of indigo, very finely powdered, 180 lbs. of slacked lime, and 120 lbs. of sulphate of protoxide of iron, or green vitriol (free from any trace of copper salt), the two latter substances being added from time to time. The greater part of the lime used unites with the sulphuric acid of the iron salt, to produce sulphate of lime or gypsum ; and the liberated protoxide of iron removes the oxygen from the indigo, becoming converted into saline oxide, whilst the reduced indigo dissolves in the excess of lime employed." Messrs. R. Schloesser & Co., of Manchester, have introduced within the last year or two a marked improvement, in the preparation of cold vats, which removes the great objections of the bulky precipitate of sulphate of lime, the formation of an oxide of iron, and the loss of indigo by its combination with the oxide of iron. The bath remaining much more fluid, the pieces are less apt to be spotted, and a better class of work is produced. To carry out their process, they add to the ordinary 2,000 gallon vat 20 lbs. of ground indigo, 30 lbs. of iron borings, 30 lbs. of their remarkable powdered zinc, and 35 lbs. of quicklime ; the whole is stirred up from time to time, for twenty-four hours, when it is ready for use. If the bath is not considered sufficiently strong, a little more lime and zinc are introduced. The chemical theory of the process is, that the zinc, under the influence of the lime, decomposes the water, combining with its oxygen, and the hydrogen thus liberated removes oxv^en from the indigo which then dissolves in the lime." An excellent description of the processes employed at Manchester, England, in preparing and working the copperas, or cold vat, is given in Urie's " Dictionary of Manufactures." 64 The ingredients necessary for setting the vat are copperas, newly slacked quicklime, and water. Various proportions of these ingredients are employed, as, for instance: 1 part by weight of indigo (dry), 3 parts of copperas, and 4 of lime ; or, 1 of indigo, of copperas, and 3 of lime ; or, 8 of indigo, 14 of copperas, and 20 of lime ; or, 1 of indigo, -\| of copperas, and 20 of lime ; or 1 of indigo, \| of copperas, and 1 of lime. The sulphate of iron should be as free as possible, from red oxide of iron, as well as sulphate of copper, which reoxidize the reduced indigo-blue. The vat, having been filled with wrater to near the top, the materials are introduced, and the whole, after being well stirred several times, is left to stand for about twelve hours. The chemical action which takes place is very simple. The protoxide of iron, which is set at liberty by the lime, reduces the indigo-blue ; and the indigo, which is then dissolved by the excess of lime, forming a solution, which, on being examined in a glass, appears perfectly transparent and of a pure yellow color, and becomes covered, whenever it comes in contact with the air, with a copper-colored pellicle of regenerated indigo-blue. The sediment at the bottom of the vat consists of sulphate of lime, peroxide of iron, and the insoluble impurities of the indigo, such as indigo-brown in combination with lime, as well as sand, clay, &c. If an excess of lime is present, a little reduced indigo-blue will also be found in the sediment in combination with lime. . . . The dyeing process itself is very simple. The vat having been allowTed to settle, the goods are plunged into the clear liquor, and, after being moved about in it for some time, are taken out, allowed to drain, and exposed to the action of the atmosphere. While in the liquid, the fabric attracts a portion of the reduced indigo-blue. On now removing it from the liquid, it appears green, but soon becomes blue on exposure to the air, in consequence of the oxidation of the reduced indigo-blue. On again plunging it into the vat, the deoxidizing action of the vat does not again remove the indigo-blue which has been deposited within and around the vegetable or animal fibre, but, on the contrary, a fresh portion of the reduced indigo-blue is attracted, which, on removal from the liquid, is again oxidized like the first, and the color thus becomes a shade darker. By repeating this process several times the requisite depth of color is attained. This effect cannot, in any case, be produced by one immersion in the vat, however strong it may be. The beauty of the color is increased by finally passing the goods through diluted sulphuric or muriatic acid, which removes the adhering lime and oxide of iron. After being used for some time, the vat should be refreshed or fed with copperas and lime, upon which occasion the sediment must first be stirred up, and then allowed to settle again, so as to leave the liquor clear. The indigo-blue, however, is in course of time gradually removed, and by degrees the vat becomes capable of dyeing only pale shades of blue. When the color produced by it is only very faint, it is no longer worth while using it, and the contents are then thrown away. In dyeing cotton with indigo, it seems to be essential that the reduced indigo-blue should be in contact with lime. If potash or soda are used in its place, it is impossible to obtain dark shades of blue." FERMENTING VATS FOR WOOL DYEING. The application of indigo-blue to wool and woollen tissues is always made by means of vats, which have special names ; as, the pastel or woad vat, the urine vat, German vat, molasses vat, &c. The reduction or hydrogenation of the indigo-blue is the result of a peculiar fermentation, which is developed within an alkaline liquor by means of nitrogenized substances and bodies rich in sugar or hydrocarbonized substances. It is known that in these conditions, especially where the temperature is slightly raised, the sugar is converted into butyric acid, and at the same time carbonic acid and hydrogen are set free. We find here the source of the nascent hydrogen wThich fixes itself upon the indigo-blue, and transforms it into white indigo, which is soluble in the alkalies of the vat. It has recently been observed that the butyric fermentation proceeds from the development of minute infusoria. These animalcule live without any supply of oxygen, and, in fact, are killed in its presence. They therefore live at their ease in the vat of reduced indigo, where no oxygen is permitted to enter. hydrocarbonaceous substances for fermentation are bran and ground madder, although molasses is sometimes used. The nitrogenized material is found in the woad or pastel, which is often added in very large proportions to the fermenting vats. It is observed by the chemists who have studied this subject most carefully, that the preparation of vats, founded upon the principle of fermentation, does not repose upon principles so sure and constant as those of the copperas vat, and that many unforeseen accidents interpose to disturb the work of an inexperienced dyer. The phenomena in fermentations are often complex. It is admitted that in these phenomena theory has not said its last word, and that empiricism is often more fortunate than science. In conducting the operations of the warm fermenting vat, the conceit of the practical dyer, so often remarked upon, is not without foundation. By practical experience and the traditions of his art he has acquired a knowledge' of the almost insensible modification in conditions which can change or arrest the chemical reaction. It is the knowledge of the workman, a knowledge almost instinctive, which can never be communicated to the books, and which is most respected by those most profoundly informed in theory. The Woad or Pastel Vat. — In former times woad, already referred to, was the only material known to the dyers of Europe for producing the blue color of indigo. For dyeing wool, the use of woad, now abandoned wholly in cotton dyeing, has been retained to the present day, generally for the purpose of exciting fermentation, and without regard to its effect in imparting color to the material to be dyed ; for the woad grown in England, and used in the dye-houses of that country, contains no trace of coloring matter. The woad, or pastel, grown in the warmer districts of France contains about two per cent of indigotine, which is regarded in that country as an important addition to the coloring material, especially for improving the tone of the color. Various substitutes, such as rhubarb leaves, turnip and carrot tops, and weld, have been tried, but without advantage, with the exception, perhaps, of weld, which is still used by some dyers. Some chemists regard the use of wroad as the remnant of a prejudice ; but the better opinion is, that this material possesses peculiar fermentiscible qualities, whose exact action science has yet to resolve. According to Schutzenberger, the most recent and highest French authority, the dimensions of the pastel vat are about 6Jfeet in diameter, by 9 in depth. 100 kilograms (221 lbs.) of pastel, in balls, is placed in the vat, which is then filled with boiling water. To this is added 10 kilograms (22 lbs.) of madder, 3 to 4 kilograms (about 6§ to 8\| lbs.) of bran, and 4 kilograms of quicklime, which has been slacked, and in the form of a bouilli. Sometimes weld is also added. After three hours of rest, the vat is well raked, and the operation is repeated every three hours. There is gradually developed a characteristic ammoniacal vapor, and a blue scum, with veins of deeper blue, forms on the surface ; and the liquid, when agitated in the air, rapidly becomes blue. These symptoms indicate the dissolution of the indigotine of the woad ; then there is added 10 kilograms (22 lbs.) of indigo which has been previously ground in water, and the vat is stirred. If the fermentation appears to be proceeding too actively, which is recognized by the disengagement of gases, it is checked by the addition of a proper dose of lime. On the other hand, the fermentation is made more active by increasing the dose of bran. The first dyes are not so good as those subsequently obtained, as the woad absorbs from the bath certain brown or yellow materials, kept in solution, and furnished as well by the pastel and madder as by the indigo itself. 100 kilograms of wool require from 8 to 12 kilograms of indigo. The vat is kept up by successive additions of indigo and lime, made in the evening. Another kind of pastel vat, prepared much like the last, receives an addition of a dose of potash. M. de Kaeppelin describes it as the one at present in general use in France. Into a vat containing from 3,000 to 4,000 litres (791 to 1,055 gallons) there is placed 75 kilograms (166 lbs.) of pastel in loaves, or which has undergone a kind of fermentation ; or, what is preferable, 80 to 100 kilograms (176 to 221 lbs.) of pastel or woad gathered without fermentation, and 10 kilograms (22 lbs.) of indigo, ground to a paste with water. This mixture is well stirred, and there is added 4 kilograms (about 9 lbs.) of Avignon madder, and the, same quantity of carbonate of potash. After the vat has been well raked there is added 2 kilograms (4J lbs.) of slacked lime, and some pails of bran. The vat is well covered, either with a wooden lid, or woollen cloths. The fermentation is allowed to proceed, and after five or six hours the vat is uncovered and raked with much care for half an hour. This operation is repeated every three hours, until it is recognized that the indigo is well dissolved. In this case the bath ought to be of a beautiful yellow color, and be covered with a light blue irised film, veined with yellow at the least movement given to the liquid. If the fermentation proceeds too rapidly, a little lime is added to moderate it. For keeping up a vat like this, and to obviate the different inconveniences to which it is subject, the dyer sometimes adds lime, or sugar, and carbonate of ammonia, sometimes madder, or bian, or even tartar-lees. These last additions are made to saturate the excess of lime which the vat contains. When lime or sugar are added, it is for the purpose of retarding the fermentation of the woad. Sugar might even entirely take the place of pastel for effecting the reduction of the indigo, and many establishments in France are commencing to use it for this purpose. A good vat, well supplied with successive additions of indigo, pastel, bran, and madder, in proportions necessary to effect and prolong the fermentation necessary for the dissolution of the indigo, may be kept up many years. Schutzenberger observes that the vats of fermentation are subject to certain maladies, the two most frequent of which are due, one to an excess, and the other to an insufficient quantity of lime. " In the first case, the liquid takes a tint more and more free of color, loses its fleuree (surface scum) and odor ; the fermentation is then arrested by the precipitation of the active matters. This inconvenience is remedied, if seen in time, by adding sulphate of iron, which eliminates the too great excess of lime. In the second, the fermentation becomes too active, passes into a putrid fermentation, and the liquid assumes a reddish tint ; a fabric dyed with indigo in this state becomes very soon discolored. The sole means of safety is to heat the bath up to 90° and to add lime. If this does not accomplish the purpose of arresting the putrefaction the vat is lost." The following account of the method of dyeing w.oollen goods with indigo by means of the woad vat is given by Dr. Ure, as that carried on in Yorkshire, the great centre of the woollen manufacture of England. " The dye-vats employed are circular, having a diameter of six feet six inches, and depth of seven feet, and are made of castiron five-eighths of an inch in thickness. They are surrounded by brickwork, a space of three inches in width being left between the brickwork and the iron, for the purpose of admitting steam, by means of which the vats are heated. The interior surface of the brickwork is well cemented. In setting a vat the following materials are used : 5 cwt. of woad, 30 lbs. of indigo, 56 lbs. of bran, 7 lbs. of madder, 10 quarts of lime. The woad supplied to the Yorkshire dyers is grown and prepared in Lincolnshire. It is in the form of a thick, brownish yellow paste, having a strong ammoniacal smell. The indigo is ground with water in the usual manner. The madder acts in promoting fermentation, but it also serves to give a reddish tinge to the color. The lime is prepared by putting quicklime into a basket, then dipping it in water for an instant, lifting it out again, and then passing it through a sieve, by which means it is reduced to a fine powder, called by the dyers ware. The vat is first filled with water, which is heated to 140° F., after which the materials are put in, and the whole is well stirred until the woad is dissolved or diffused, and it is then left to stand undisturbed overnight ; at six o'clock the next morning the liquor is again stirred up, and five quarts more of lime are added ; at ten o'clock five pints of lime are again thrown in, and at twelve o'clock the heat is raised to 120° F., which temperature must be kept up until three o'clock, when another quart of lime is introduced. The vat is now ready for dyeing. When the process of fermentation is proceeding in a regular manner, the liquid, though muddy from insoluble vegetable matter in suspension, is of a yellow or olive yellow color ; its surface is covered with a blue froth or copper-colored pellicle, and it exhales a peculiar ammoniacal odor ; at the bottom of the vat there is a mass of undissolved matter of a dirty yellow color. If there is an excess of lime present, the liquor has a dark green color, and is covered with a grayish film, and, when agitated, the bubbles which are formed agglomerate on the surface, and are not easily broken. Cloth dyed in a liquid of this kind loses its color on being washed. This state of the vat is remedied by the addition of bran, and is of no serious consequence . When, on the other hand, there is a deficiency of lime, or, in other words, when the fermentation is too active, the liquor acquires first a drab, then a clay-like color ; when agitated, the bubbles which form on its surface burst easily, and when stirred up from the bottom with a rake it effervesces slightly, or frits, as the dyers say. If the fermentation be not checked at this stage, putrefaction soon sets in, the liquid begins to exhale a fetid odor, and when stirred evolves large quantities of gas, which burns with a blue flame on the application of a light. The indigo is now totally destroyed, and the contents of the vat may be thrown away. No further addition of woad is required after the introduction of the quantity taken in first setting the vat, the fermentation being kept up by adding daily about four pounds of bran with one quart or three quarts of lime. Indigo is also added daily for about three or four months. The vat is then used for the purpose of dyeing light shades, until the indigo contained in it is quite exhausted, and its contents are then thrown away." This author adds : " Woollen cloth, before being dyed, is boiled in water for one hour, then passed immediately under cold water. If it be suffered to lie in heaps after being boiled it undergoes some change, which renders it afterwards incapable of taking up color in the vat. In dyeing, the cloth is placed on a net-work of rope attached to an iron ring, which is suspended by four iron chains to a depth of about three feet beneath the surface of the liquor.* The cloth is stirred about in the liquor by means of hooks for about twenty or thirty minutes. It is then taken out and well wrung, It now appears green, but, on being unfolded and exposed to the air, rapidly becomes blue. When the vat has an excess of lime the cloth has a dark green color when taken out. It is then passed through hot water, and dipped again if a darker shade is required. The Indian Vat. — This presents much analogy to the woad vat, as the fermentation of vegetable matters effects the transformation of the indigo-blue. According to Dr. Calvert, the Indian vat, probably so called from its origin in the East, is taking the place in England of the old woad vat for dyeing wool and woollens. He describes its preparation as follows : 8 lbs. of powdered indigo is added to a bath containing 3 J lbs. of bran, 3^ lbs. of madder, and 12 lbs. of potash, which is maintained for several hours at a temperature of 200° F. It is then allowed to cool to 100° F. , when fermentation ensues. After about forty-eight hours the indigo is rendered soluble, being reduced by the decomposition of the sugar and other products contained in the bran and the madder root during the process of fermentation. The distinguishing feature of this vat is the use of potash. The Indian or potash vats are spoken of by the best authorities as more easy to manage than the woad vat. They are less subject to accidents, and yield #their coloring material more readily to the fibre, while three times as much wool can be dyed in the same time. On the other hand, they do not last so long, and require to be renewed at the end of twenty-five or thirty days. Besides, the fibres dyed in the potash vat have a darker shade than those dyed in the woad vat, owing to the large quantity of the coloring matter of the madder dissolved by the potash, which becomes fixed on the stuff with the indigo-blue. The Urine Vat, but little used except for domestic dyeing, is founded upon the same principles as the other fermenting vats. This excretion, when putrefied, contains at the same time the nitrogenized principles which work as ferments and the alkali in the form of ammonia necessary for dissolving the indigo. late years in the fermenting indigo vats by which the expense of madder is avoided. They are now prepared by adding to water, at a temperature of 200° F., 2 buckets of bran, 26 lbs. of soda crystals, 12 lbs. of indigo, and 5 lbs. of slacked lime. After five hours the bath is allowed to cool to 100° F., when fermentation ensues, and the indigo is dissolved in the alkali. This is, in fact, the German vat, soda taking the place of the potash, and the only fermenting material consisting of bran. The German Vat is largely used by the dyers in the north of France, and is considered as more advantageous than the Indian vat, because the employment of soda is more economical than that of potash, while the vat can be maintained as long as two years. The vats used by them are prepared as follows : The water is heated to a temperature of 95°, and receives 20 pails of bran, 11 kilograms (about 24 lbs.) of crystals of carbonate of soda, 5.5 kilograms (11 lbs.) of indigo, and 4J lbs. of slacked lime. After twelve hours, the temperature having been kept at 40° or 50°, fermentation commences, the liquid becomes of a greenish blue color, and disen^a^es bubbles of £as. Indigo, soda, and lime are put in from time to time in the proportions above indicated, and also from six to eight pounds of molasses. At the end of the third day the vat is fit for use. M. de Kseppelin, writing in. 1864, informs us that the reduction of indigo by means of molasses, is at% present largely employed in the great establishments for dyeing woollen cloth at Sedan, Louviers, and Elboeuf. The vat used is of very large dimensions, and from twentytwo to twenty-six pounds of indigo are dissolved in it ; an equal weight of molasses is used, and three or four times the same weight of potash made caustic by a proportionate addition of lime. The space reserved for this subject in our present paper will not permit us to enter upon a description of the processes used in the American dye-houses. This, as well as the applications of indigo in printing, and the uses of sulphate of indigo, must be deferred to another number. repetition, bring out in bolder relief a statement which presents the philosophy of all the various processes of the indigo vat, and at the same time, a conclusive argument for the use of this materia], in preference to all cheaper substitutes. Indigo cannot enter into a fibre until it is dissolved. It cannot be dissolved so long as it is in a blue state. When reduced by any of the processes above described to the white state, it is easily dissolved, and can enter the pores of the fibre. Upon exposure to the oxygen of the air it takes up an equivalent of oxygen ; it returns to the blue state, and, being then insoluble, it cannot be washed away from the fabric, and being saturated with oxygen it cannot be changed by air or light. This theory of the application of indigo involves a lesson to manufacturers, dealers, and consumers, especially of woollen fabrics. The theory, as well as experience, dating back to the dawn of the textile arts in the East, establishes that this material is incalculably superior to any other, in permanence at least, for imparting to woollen fibre a blue color, or as a foundation for most of the darker colors. By far the largest proportion of all cloths are of dark colors, — blue, black, green, brown, gray, or mixed, — and can advantageously receive in all or a portion of the fibre constituting them a direct dye or bottom for other dyes from indigo. It may be safely stated that, as a whole, no cloths in the'world are manufactured from such good wool as those produced in the United States. We might expect that the shoddy goods of Yorkshire should be further falsified by fugacious dyes ; but is it not a shame that our admirable wool should be deprived of half its value by parsimony in dyeing? The slightest shortcomings in dyeing are revealed in wrear. The writer cannot forbear referring to an illustration' directly before his eyes. He is wearing a garment, reduced now to the retired service of an office coat, made of an admirable cheviot cloth of American manufacture. The cloth originally was selected not only for its excellent texture, but as an illustration of philosophical principles applied in the formation of color. The tissue was made by weaving three yarns of distinct colors, — blue, yellow, and red. Either of those hues alone would have been glaring and conspicuous, but, by the law of color, the combination of blue, red, and yellow makes black, and the new cloth at a distance had the effect of a dark mixture. Upon exposure to ordinary wear, the yellow and red have retained their pristine hues ; the blue, not being indigo dyed, has faded ; and the original dark mixture, although sound in fabric, has become of a yellowish brown. The extra expense of a permanent dyeing material forms so small a proportion of the whole cost of a finished garment, that it ought not to be generally spared. The reform cannot be made by the manufacturers ; it must be made by the dealers, and especially by that class of producers which has risen in our day into such great importance, — the manufacturers of ready-made clothing. If they would demand of the manufacturers, and furnish to their customers cloths more permanently dyed, it would be another step in the direction to which these establishments are tending, — the supply of the chief portion of the woollen clothing of the people. The manufacturers would gladly aid them ; for it is the growing sentiment of American manufacturers that all their productions should be, in the proverbial phrase adopted from the dye-house, as expressing the highest excellence, — true blue. BIBLIOGRAPHY. Citations of authorities having been but partially made in the preceding article, the writer, for the purpose of giving his sources of information, and for the convenience of those who wish to pursue the subject further, appends a list of the more important works which he has consulted : — Schutzenberger's Traite des Matieres Colorantes, t. ii. (the most recent and best modern authority) ; Bancroft's Philosophy of Permanent Colors, vol. i. ; Edinburgh Encyclopaedia ; Berzelius, Traite de Chimie, t. vi ; Chevrueil, Lemons de Chimie Appliquee a Teinture, t. iii. ; Dumas, Chimie Appliquee aux Arts, t. viii ; Wurtz, Dictionnaire de Chimie, 1872, art. Indigo ; Indigo et son Emploi, par De Kseppelin ; Annales du Genie Civil, 1864, t. iii. ; Lectures of Dr. Grace Calvert, Chemical News, Aug. 9 and 23, 1872 ; O'Neill's Dictionary of Dyeing and Printing ; Napier's Chemistry Adapted to Dyeing ; Muspratt's Chemistry Applied to the Arts, articles Indigo and Dyeing; Ure's Dictionary of Manufactures, ed. of 1860; Proceedings of Royal Society, vol. xvi. ; Proceedings of Literary and Philosophic Society of Manchester, vol. iv. ; McCulloch's Dictionary of Commerce, ed. 1869 ; Dictionnaire Universel du Commerce, &c, ed. 1861 ; South Carolina Production . — Ramsay's History ; Drayton's South Carolina ; Silliman's Journal, vol. xviii. A more complete bibliography is gi^en in Schutzenberger's work. We entered upon the subject of indigo, which we have treated at some length in our last issue, as much in the interest of the people as of manufacturers, for we were deeply impressed with the conviction that no improvement in our manufacturing processes would confer more benefit upon the masses than imparting stability of color to the clothing of the people. When one has a deep conviction upon a subject, upon which others have equal opportunities for judging, he may be sure that he is not alone in his impressions. He is moved by one of those waves of thought which, operating simultaneously upon many minds, gives that uniformity to public opinion at which we so often wonder. We are gratified to find, from responses to our last article, that we are not alone in our conviction of the importance of reviving "true blue 99 dyes. The head of a mercantile house, the extent of whose clientele in mills both of wool and cotton is hardly surpassed, has assured us that we have not overstated the reform in dyeing which we have advocated. He had long shared in our convictions. Pointing to the throng of men in the crowded street, where we were conversing, he remarked that there was hardly a man in the crowd whose clothing would not have been improved by indigo dye. " The failure to use indigo dyes," he emphatically said, " costs the laboring people of this country millions of dollars every year. The fault is not to be charged to our own manufacturers alone ; for the blue coat which I wear, and which I bought in Paris, annoys me by the crocking caused by its aniline dye." In one very large mill of which he is director as well as selling agent, he is putting his principles in practice. All the heavy blue cloths intended for popular consumption are faithfully dyed, and each bears a stamp, " Warranted indigo dyed." The ready-made clothing establishments which largely consume these goods have already found their advantage in purchasing them, and a similar stamp is attached to each article made from this cloth. Some of our most celebrated cotton fabrics have won and still retain their reputation by the use of indigo dyes. The ginghams are a signal illustration. The blue check is formed by weaving cotton yarns dyed blue in the cold indigo vat with undyed yarns. These goods can be washed indefinitely without change. Another illustration is the famous A. B. A. Amoskeag tickings, an article of such excellence that the question of the right to use trade-mark A. B. A. gave rise to the leading American case in this branch of law.* A prominent feature in these goods was and still is the permanence of the dye in the blue stripe, produced by the cold indigo vat. Still another illustration is the blue and white " shirting stripe w first made by Mr. Samuel Batchelder, at the Hamilton Mills, now so generally adopted for sailors' shirts. The indigo dye enables the color to resist the roughest possible usage. To recur to the application of indigo dyeing to wool and woollens. We have been unable, although we have written more than fifty letters of inquiry upon the subject, to learn of any peculiarity or improvements in the American processes of wool dyeing with indigo, f Our dyers are for the most part for- t A reply by Mr. D. R. Whitney, an extensive indigo importer, to a letter of inquiry, enables us to correct some errors in our former article, under the head of " commerce in indigo." The value of export from India in 1862-63, stated in dollars, through a eigners. For this reason, or because the art of indigo dyeing has long since reached perfection in the best establishments abroad, they rigidly pursue the old European methods. The best dyers regard the successful management of the warm fermenting vats for wool as the highest test of their art. We have already spoken of the complicity of the phenomena in fermentations. Practical dyers endow the fermenting vat with a sort of personality. * The diagnosis of a sick vat requires that sort of instinctive knowledge which experience gives to the practised physician. The impatience of our young Americans will not permit them to serve the long apprenticeship necessary to acquire the proper experience. The artisans not thoroughly trained will naturally prefer the dyes and processes introduced by modern science, which require but little skill in their application. It is a curious fact that the influence of the national government has been largely instrumental in preserving the old system of indigo dyeing. Thanks to the QuartermasterGeneral's Bureau, or the man of science, General Meigs, who presides over it, indigo dyed cloths have been persistently insisted upon for the army. The late war gave a new impulse to indigo dyeing. A skilled dyer, whom we have consulted, was constantly employed in Connecticut, on a tour of professional inspection of a dozen or more different establishments making army goods. No doctor, he says, ever found in hospital practice more complications of disease than he found in the ail- typographical error, should have been pounds sterling ; thus, instead of $2,126,814, read .£2,126,814. It is stated in our first article that the telegrams show a decline of price of indigo in the Indian trade of from 50 to 75 per cent; "per cent" should read " rupees," which would make a decline of from 25 to 30 per cent. The reason for the decline, as stated by Mr. Whitney, is the unusually large crop of this year. The average crop of indigo in Bengal is about 100,000 maunds. The crop of this year is 135,000 maunds, about 30 to 35 per cent above the average. According to Mr. Whitney, the consumption of Bengal indigo in the United States was 2,458 cases of 270 lbs. to a case on an average, in 1871; and in 1872, 1,802 cases. Guatemala indigo, 3,132 serroons in 1871, and 2,578 serroons in 1872. ing vats. Among other difficulties there was a deficiency of imported woads, although the cultivation of excellent woad immediately sprung up in Connecticut. In the mean time carrot and rhubarb tops were used as substitutes for the fermenting material of the woad. Carrot-tops grown expressly for that purpose brought as high as twenty-five cents per pound. Since the war the requisitions for indigo-dyed woollen goods have not relaxed, and the art is not likely to be lost. With the real difficulties which attend the process, it is hard for indigo dyeing to sustain itself in the face of cheap substitutes of easy application, such as the Nicholson blue. It is exceedingly difficult to piece dye with indigo and preserve a uniform hue upon the cloth. Hence indigo dyes are generally given in the wool. The wool absorbing the foreign material of the dye is more difficult to work in the operations of carding and spining. In other words, a finer and costlier wool is required. A great desideratum therefore is a means of piece dyeing with indigo so as to preserve a perfect uniformity of hue throughout the piece. This, we are happy to say, has been recently successfully accomplished by one of the largest and most faithful of our clothmaking establishments. It would be premature, before the patents are secured for this invention, to explain the ingenious and expensive apparatus devised for this purpose, which constitutes in fact a battery of vats so arranged that the operation may be continuous. The experiments authorize the statement that bottom dyes of indigo, so desirable for a great variety of colors, can be applied with no other additional cost than that of the dyeing material. When this establishment, as it proposes, stamps upon the cards which designate goods, already so admirable in material and texture, " Warranted indigo dyed," we shall regard it as an era in the American card-wool manufacture. The old European woad vat process is that used in all our establishments. Mr. Henderson of the Washington Mills, whose experience as a practical dyer of wool is exceptionally large, informs us that he has found no work so instructive upon this process as Napier's "Chemistry of Dyeing " (published by Henry Carey Baird, of Philadelphia, 1869). Napier's description of the process is extracted from Dumas's "Lectures on Dyeing." The appreciation expressed by so competent a judge induces us to reprint Dumas' description in an appendix to this article. adverted to. In Part I. of our notes we have treated only of the application of this substance in dyeing by means of reduction through the indigo vat. Indigo may be applied by means of reduction in the printing of fabrics, as well as in dyeing them. A true scientific arrangement would compel us next in order to consider this other application of indigo by means of reduction. But the more natural and practical order is to pursue the subject of dyeing, and to consider next the applications of the derivatives from indigo in dyeing proper. The powerful action of sulphuric acid upon indigo, and the bright and lively blue color thereby produced, had been observed by chemists long ago ; but no person appears to have applied this color upon cloth, until it was done about the year 1740, by Counsellor Barth, at Grossenhein, in Saxony. The vividness of the dye, and the facility with which it was applied, brought it into great vogue under the name of Saxon blue, from its origin. Its popularity in former times is evinced by the words of the old song, " The Blue Bells of Scotland : " — The Saxon blue consists simply of a solution of indigo, the Guatemala blue indigo being preferred, in sulphuric acid suitably diluted with water. The result of this reaction is not a single chemical substance, but two acids giving different tints, one called sulpho-purpuric acid or phenicine, and the other sulphoindigotic acid ; the first giving to wool a reddish-violet color, and the other a pure blue. A third compound has been indicated by Berzelius, the nature of which has not been determined. Whether one or the other of the two named acids, or the two combined, shall be produced by the reaction between the sulphuric acid and the indigo, depends upon the duration of the contact, the temperature of the mixture, and the nature and proportion of the acid used. ' ' 1 part by weight of indigo, finely rubbed. 1 „ „ „ „ Nordhaussen acid. 1 „ „ „ „ ordinary sulphuric acid. Leave for forty-eight hours, then heat until a drop turned into water will dissolve without producing a precipitate. Leave to cool, and dilute with water till the strength is brought to 18 Beaume." Napier says that he has found the following method of preparing sulphate of indigo, in quantities for use, very satisfactory : " The indigo is reduced to an impalpable powder, and completely dried by placing it on a sand bath or flue for some hours at a temperature of about 150° F. For each pound of indigo six pounds of highly concentrated sulphuric acid are put into a large jar, or earthen pot, furnished with a cover. This is kept in as dry a place as possible, and the indigo is added gradually in small quantities. The vessel is kept closely covered, and care taken that the heat of the solution does not exceed 212° F. When the indigo is all added, the vessel is placed in such a situation that the heat may be kept up at about 150° F., and allowed to stand, stirring occasionally, for forty-eight hours. These precautions being attended to, we have uniformly found that any failure occurring was clearly traceable to the impurity of the indigo or weakness of the acid used." The processes for producing and separating the two acids derived from the combination of sulphur and indigo are minutely given by Berzelius, in vol. i. of his w Traits de Chemie," who states this curious fact illustrative of the peculiar affinities of wool with certain dyeing substances. Wool or flannel thoroughly scoured, when immersed in the blue solution of indigo with sul- phuric acid, acts as a base : it combines gradually with the acid blue, and becomes itself colored of a deep blue. When saturated with color, it is withdrawn. Fresh wool is introduced until the bath yields no more color. If sublimed or perfectly pure indigo is used, there remains in the bath nothing but free sulphuric acid. The wool thus plays the part of a base with which the blue acids combine. The dyed wool is afterwards washed and treated in feeble alkaline bath (ammonia), which redissolves the blue. This method of purifying the Saxon blue is still practised by French manufacturers. The combination of indigo with sulphuric acid, sometimes improperly called sulphate of indigo, is known by the dyers here and in England under the name of chemic. The name of chemic blue or green is also given the dyes formed from the indigo extract hereafter spoken of. It is largely used for making certain greens required in Scotch plaids. The old Saxon blue or simple solution of indigo with sulphuric acid is now seldom prepared by the manufacturers themselves. It is now generally prepared for them, and furnished commercially under the name of indigo extract. The finer qualities used for fine dyeing and printing are known under the name of carmines of indigo, neutral extract, soluble indigo, ceruline, &c. The production of indigo carmines, which are simply alkaline sulphindigotates or sulpho-purpurates, is founded upon their insolubility in a liquid charged with a salt. If, for example, we dissolve one part of indigo in four parts of fuming acid, and dilute the liquid with sixty or eighty times its weight of water, it will contain, besides the sulphindigotic acid, an excess of sulphuric acid. By adding one part of crystals of soda so as to neutralize the bath, there will be formed not only sulphindigotate of soda, but sulphate of soda : as the former is insoluble in the saline liquid, the presence of the sulphate of soda causes the precipitation of the sulphindigotate in deep blue floccules. These are collected on woollen filters and washed to remove the sulphate of soda and a green coloring material, probably a modified chlorophyl, which the paste often contains, and which has the singular property of fixing itself on silk, but not on wool. The carmines are divided according to their richness in indigo into simple carmine (4.96 per cent of indigo, water 89, saline materials 57), double carmine (10.2 per cent indigo, water 85, salts 4-8), triple carmine (12.4 percent indigo water, 73.7, salts 13.9). A species of solid carmine known as Boiley blue or purple is in high repute in France. The carmines may be tested by dyeing a specimen of wool in an acidulated bath to which cream of tartar has been added. The presence of the green matter, so objectionable to silk-dyers who make much use of these carmines, is detected by rubbing a small quantity of the carmine on a piece of glazed paper, which, when the color dries, gives a color varying from blue to a rich copper color : if any green coloring matter is left, it shows itself by a green aureola around the blue color. The method of applying the carmines in* dyeing wool and silk, — for they are not adapted to cotton fabrics, — as given by M. de Kseppelin, is as follows : — The operation is conducted in small wooden vats, provided with openings for manipulation, and pipes for inducting steam to heat the baths to the proper temperature. It consists of two parts, that of mordanting and dyeing. The former is thus conducted. For each kilogram of tissue which has been previously scoured and bleached, there are provided 200 grammes of cream of tartar and 250 grammes of alum. These are dissolved in the bath of wrater of the vat, the temperature is raised to boiling heat, and the tissue is immersed in the bath f of an hour while it is worked over through the opening for manipulation. The pieces are then taken from the bath, to which is added a solution of the carmine in water containing a quantity of coloring matter proportionate to the intensity of the blue sought for. The solution ought to be prepared with care and passed through a silk sieve, so that the small insoluble grains which might have been left through bad fabrication may be left on the sieve. After the pieces have been manipulated in the colored bath, so as to exhaust the color and obtain the required blue, they should be rapidly washed in running water and dryed in the shade. Silk stuffs are dyed in the same way ; but the alum should be previously applied cold by means of a saturated solution of alum, in which the stuffs should be immersed for an hour. COLORS NOT FAST. In regard to all the combinations of indigo with sulphuric •» acid, including the carmines, it must be observed that their application does not constitute true indigo dyeing : the colors are not fast. It is not pure indigotine which is fastened on the tissues as in the vat dyeing, but another compound of indigo with the sulphur. Berzelius observes that "the color of soluble indigo is fully as alterable and fugacious as that of the colors extracted by the decoction of vegetable materials. By a long exposure to the sun the indigo blue is destroyed : it becomes green during evaporation, and changes its nature." The carmines as well as the sulphur acids are easily decolorized by reducing agents, such as hydrogen and sulphuretted hydrogen, although they gradually assume their original color when exposed to the atmosphere. We are informed by some of the older dealers that imported cloths and merino stuffs known as "Saxony" were formerly largely sold in our shops, but that, notwithstanding their attractiveness to purchasers, they were objectionable on account of the instability of their color. APPLICATION OF INDIGO IN PRINTING STUFFS. Our notes would be incomplete without some reference to the uses of indigo in printing fabrics. In pursuing this branch, we are embarrassed on the one hand by the consideration that the subject is too technical for the general reader, and on the other by the consciousness that it would be presumption in us to attempt to instruct those skilled in the art. It may not, however, be without benefit in producing a higher appreciation of science for the general reader to observe how science comes in play, even in the printing of a single color ; while to the skilled reader our notes may possibly be of value as a vehicle for conveying some receipts taken from works not easily accessible. COTTON WARPS. This branch of our subject is directly allied to the one last considered, the application of the compounds of sulphur and indigo ; for indigo is applied to printing wool and silk principally in the form of indigo carmines. These applications are less numerous than they were formerly, since they have been replaced by Prussian blue, and more recently by the aniline blues, which are now generally used. When the carmines are used, it is for making sky blues, and they enter into the composition of some greens and browns. The salts of alumina and vegetable acids are used to fix the indigo carmine upon tissues of wool and silk. Some receipts recommended by M. de Kseppelin, himself a practical printer, are given in a note.* In printing tissues of wool with cotton warp, the carmines are not used alone. They are combined in certain proportions with cyanites of iron and potash, to obtain upon the cotton a blue color of equal intensity with that produced by the carmines upon wool. It is also necessary to previously mordant the fabrics by means of a solution of oxide of tin or caustic soda,^ which is precipitated on the fibres by passing through a bath oft water, to which sulphuric acid has been added. \ Before entering upon methods used in large establishments, it may not be without interest to observe the processes still used in Java for printing calicoes, which the natives prefer to any imported from Europe. In Java there are no factories, and the women in each family make and dye or print all the cotton cloths required for their own consumption. They apply by means of a brush or pencil, which they use with great skill, to the cotton tissue which they wish to cover a thin coating of wax mixed with a little resin, the wax being applied to all the parts where the design, which has been first traced upon the cloth, requires that the fabric should remain uncolored. They then immerse the stuff several times in an indigo vat until they have obtained the desired tint. The stuff is afterwards washed and dried for a new application of the wax, carefully applied with a pencil as before. The cloth is then immersed in a bath of a different color, made with madder or catechu, but always of some dye which is perfectly stable ; and the operation is repeated according to the number of colors desired. By these successive applications of wax and immersions into different vats, they succeed in producing very complicated and harmonious colors, while no European goods compare with them in stability of dye. In the European and our own manufacture, the blue bottoms upon vegetable fibres, made by immersion in the indigo vat, are combined with white impressions, or others variously colored, by two distinct methods. Sometimes there is printed upon the cloth before dyeing in the indigo vat a preparation called a reserve or resist, which prevents the indigotine from being deposited in the places where it is applied. Sometimes, on the contrary, the indigo, which has been uniformly fixed upon the fabric, is destroyed in certain places marked out by printing upon them certain chemical agents, called discharges. The reserves are mechanical, resisting the penetration of the dye, such as wax and pipe clay, or chemical. The last, through these acid or oxidizing properties, cause the precipitation of the indigotine before it has touched the fibre or penetrated into its pores. Such are the salts of copper and bi-chlorate of mercury. Other bodies perform the part both of mechanical and chemical reserves. The salts of zinc or alumina, for instance, which are frequently used, produce at the same time a deposit of indigo white and a gelatinous covering of hydrated oxide of zinc or aluminium. The composition of a good reserve is declared to be principally a question of good proportions of the constituent parts, varying with the strength of the vat and the intensity of the blue which is desired to be reserved. The first condition is that it hardens immediately after immersion in the vat : if it softens, on the contrary, it will cause the running of the color. In other words, the acidity of the impression should be proportionate to the strength and alkaline character of the vat. The white reserve, that most generally used, is composed of pipe clay, gum, verdigris, and sulphate of copper. The styles of work produced by dipping with reserves are generally of a cheap and low class. The system is clumsy and expensive, and is only tolerated because of the want of a method of directly applying indigo, which will yield the deepest shades. Certain styles, formerly in great vogue, called Lapis, and forming one of the richest branches of the cotton-printing industry, are founded upon the use of reserves ; and in these styles, by very simple means which we shall not attempt to describe, different colors produced from madder, catechu, &c, are produced upon the fabric so perfectly surrounded by blue that the. eye cannot detect the slightest want of continuity. This fabrication has the greatest perfection in Russia. The imitation cashmere fabrics of cotton imported from that country, formerly much in fashion for dressing-gowns, are specimens of this fabrication. The great stability of the colors is a remarkable feature of these goods. The system of resists or reserves possesses the inconveniences of not producing impressions of great firmness, and of requiring very strong vats. When the strength of the vat is partially exhausted, they may be thrown aside. These inconveniences are obviated by the system of discharges (enlevages). In this system the cloths are vat dyed of a uniform blue. The strength of the vat is of less importance, and it can be used until the indigo is quite exhausted. The means of destroying the indigo which has been fixed upon the fibre are founded on the use of active oxidizing agents, which transform the insoluble indigotine into soluble isatine. The agent generally used is chromic acid. As this acid cannot be incorporated with the thickening to be printed, as the thickening would produce oxide of chrome, the cloth is passed through a strong solution of chromate of potash, and dried in the shade. The required pattern is then printed on the cloth with a mixture whose principal elements are acids which are susceptible of setting free the chromic acid on the tissue, which then acts upon the indigo producing a white pattern. The acid generally employed for freeing the chromic acid is oxalic acid, thickened with British gum, dextrine, or starch, with the addition of pipe clay. To prevent running, nitric, sulphuric, or tartaric acid are sometimes used.* By the method of discharges the white designs upon blue are brought out with a distinctness which it is impossible to obtain by resists, while the most delicate work of the graver can be exactly reproduced upon the tissue. The first step in the art of printing indigo tine upon calicoes was the application of what is called pencil blue. Instead of immersing the fabrics in an indigo vat, the indigo white formed in a very strong indigo vat was thickened and applied locally to certain places on the cloth. The preparation was painted upon the cloth by means of pencils made of willow sticks, the ends of which were broomed up into a kind of brush. The style was hence called pencil blue. The methods now used to apply white indigo locally are of two kinds. The china blue process, and the solid blue process, sometimes called fast or precipitated blue. The china blue process derives its name from the resemblance of its color to the blue on the old china ware. It has great depth of tint, and permanency. It is scarcely used now, except for certain articles requiring great depth of color, such as certain furniture goods, and by the Germans and Swiss for the manufacture of calicoes for exportation to India. We do not venture to condense the descriptions at our hand of the processes for applying the china blue and the solid blue, and translate those furnished by chemists of high authority. After the method indicated by Darwin in his recent works, we present them in smaller type, with the perhaps unnecessary suggestion that they may be passed over by the general reader. ger, is very simple. The indigo, reduced to an impalpable powder and to the intensity of the blue. The pieces thus prepared must be dried away from direct solar light or too much heat. In fact, under the action of these agents, the bichromate would be decomposed and the tissue altered. The pieces are often rolled up to prevent this effect. After the pieces are printed, they are passed into a vessel containing water and holding chalk in suspension in sufficient quantity to give it a milky aspect. The temperature of the bath is raised to 60° R. The excess of acid of the color applied is saturated by the chalk, and the excess of bichromate of potash with which the tissue is impregnated is dissolved in the bath. The pieces are afterwards washed and passed through slightly soapy water. thickened, is printed by a plate or roller. After drying, the tissue seems dyed blue, more or less deep, according to the proportion of coloring material used ; but it is only a blue of application, which can be removed with the thickening, by the slightest washing. The object is now to reduce and redissolve the indigotine in place to enable it to penetrate the fibre at the end of a consecutive oxidization, and without producing a running of the color or altering the purity and distinctness of the contours of the design. I owe to M. Ed. Schwartz some valuable hints upon the fabrication of this style, which is also described with much care and details in the treatise on printing by M. Persoz. The reduction of the indigo is obtained by alternate passages of the printed tissue into vats containing, — the first, quicklime slacked ; the second, sulphate of iron ; the third, soda. The operation is terminated by a passage through a bath of sulphuric acid, which removes the oxide of iron and precipitates the indigo white by hastening its oxidation. of the treatment. The operator uses six vats, — for instance, two lime vats, provided each with 12 kilograms of lime; a copperas vat at 70 Beau me ; a caustic soda vat marking 140 Beaume ; a sulphuric acid vat with 500 grammes of acid (par mesure d'eau) ; and finally a vat of pure water. Gum Senegal 6 kilograms. Pass through a sieve ; leave some time at rest, and stir whenever used. Caraccas indigo is preferred because it can be broken into a finer powder and gives a finer paste. The piece is treated a quarter of an hour in the first lime vat by giving it a light movement from above to below ; it is left a quarter of an hour in repose in the sulphate of lime vat ; a quarter of an hour in the second lime vat ; a quarter of an hour in the copperas vat ; five minutes in the caustic soda ; half au hour in the sulphuric acid, and then thoroughly rinsed. To each lime vat there is given 2 kilograms of lime per piece of cloth. To the vitriol vat there is added 50 kilograms of sulphate of iron for each dozen pieces. The soda vat is renewed after 5 pieces by the addition of 12 kilograms of salt of soda, which has first been made caustic. The acid vat receives 25 kilograms of acid after 5 pieces, and ought to be renewed whenever it becomes saline. The other vats must be cleared out whenever the deposit becomes too great for success. M. Ed. Schwartz recommends as important conditions, (1) the perfect causticity of the tissue, and an average strength of 140 Beaume ; (2) the neutrality of the sulphate of lime vat. For this end old iron should be boiled in it. After leaving the sulphuric acid vat the pieces are rinsed in the water vat, then in river water, and afterwards should be soaked in a sulphuric acid bath at 40 Beaume, for the purpose of dissolving the last traces of the peroxide of iron adhering to the fibre. The fabric is then washed in water and finally passed through a soapy water at 40° R. Solid or precipitated blue, Schiitzenberger's receipt. — The process consists in printing indigo white precipitated in a vat, in a thick paste to dissolve it on the tissue by a passage through an alkaline bath (lime or soda), and of reprecipitating it by oxidizing it as soon as it has entered the fibre. Indigo white is too alterable to be printed with success, so it is generally precipitated in combination with a stannic hydrate (hydrate of a salt of tin), which gives it body and preserves it from a too rapid oxidation. The stannic indigotate in paste, or as it is generally called precipitate of indigo, is prepared by turning into the clear portion of a strong copperas vat an acid solution of protochlorate of -tin, and filtering it upon woollen filters, — as much as possible away from the air. The deposit is made into a paste with gum water ; a salt of tin is often added to prevent oxidatiou. It is important to prevent the transformation of the indigo white into indigotine before printing. This indigotine would not fix itself on the fabric. Moreover, after printing, it is necessary to hasten the dissolution of the indigo white to enable it to penetrate the fibre. It is sufficient for this end to pass it through milk of lime. The stannic combination is immediately destroyed ; the colorable matter unites itself with the lime, and the color passes into a pale gray with apple green. The indigo white becomes momentarily soluble ; but the presence of the excess of lime and the thickening, as well as the attractive affinity of the thickening, prevent any running. The piece on issuing from the lime water is placed in running water, when reoxidation commences, which this time fixes the color. The piece is finally passed through a sulphuric acid bath to absorb the lime, and washed. By adding to the color a salt whose base precipitates in the milk of lime and oxidizes in the running water, and replacing the simple acid bath by an acid bath with yellow prussite, the intensity of the blue is increased through the formation of Prussian blue. 15 gallons cold water. Stir well from time to time, until the liquid has assumed a yellow color and deep blue veins or streaks appear on its surface. When this moment arrives, draw off the clear liquor, and precipitate every ten quarts of it with To the remainder of the mixture of lime and indigo, 15 gallons of water may be added, and the whole stirred ; and when settled, the indigo may be precipitated from the clear liquor as before. This operation may be repeated a second time before all the indigo is exhausted. Although we have seen beautiful effects from the application of the solid blue of indigo on, prints at our Pacific Mills, the colors produced by Prussian blue and aniline are so much more brilliant and easy of application that the use of indigo in printing goods for ordinary consumption is likely to decline rather than increase. It will be otherwise if we should ever manufacture for the East India markets. Here is a field still open for our manufacturers. Mr. Watson, in his beautiful work on " The Costumes of the People of India," remarks that "British manufacturers have hitherto failed to appreciate Oriental tastes and habits, and hence supply but an insignificant part of the clothing of the two hundred million persons that form the population of what is commonly spoken of as India." The great defect, he observes, is the want of stability of color in the cotton fabrics introduced, — this stability being an imperative demand in the Oriental markets. The applications of indigo to cotton fabric are altogether secondary, in our mind, to its relations to the woollen manufacture. If we have felt called upon to say a word in behalf of the most ancient and best ally which the fibre of wool has ever had, it is because the vividness of color of the new products of coal, and the fascination which the application of the recent discoveries of science always possesses, is threatening the eclipse of the more ancient sober and solid dyes. Let the new colors have their place as auxiliaries, not as substitutes for the ancient dyes. Let them serve to give a bloom* to goods, but let the foundation be the good old dyes which the experience of ages has proved to be the most unalterable by light and air. The recent wonderful discovery of alizarine, or artificial madder, in coal tar products, has led practical men to expect too much from science. The opinion is quite prevalent among manufacturers that artificial indigotine has already been obtained from the * Guernsey Blue. — The darkest of the Nicholson Fast Blues. On a bottom of barkwood, camwood, madder, or inferior indigo, produces an indigo blue which will stand all the acid tests the same as colors made from indigo. Serge Blue. — It will be found very serviceable to give bloom to goods dyed with indigo, and by itself shows a very grood indig > tost with nitric acid. — Instructions for Working the Atlas Works Aniline Dues. same source. And some manufacturers are sanguine that the difficulties of indigo-dyeing will thus be resolved. It is not improbable — for what is impossible to modern chemistry ? — that this result will yet be partially obtained. But we have looked over all the recent foreign chemical reviews, and personally consulted some of our best chemists, and we can find no authority for the prevailing opinion that artificial indigotine has been produced. If the production of artificial indigotine should be realized, the only benefit would be the possible cheapening of the material. The difficulties of the indigo vat would still remain ; for we cannot too often repeat, that in the very difficulties of the process, or in the insolubility of blue indigotine by ordinary agents, consists the excellence of the dye. Indigo Blue. — We give a solid dye of indigo blue to wool by plunging it into an alkaline solution of indigo white, and then exposing it to contact with the air. The solution of indigo white is prepared in a vessel usually from eight to nine feet in depth, and six to seven feet in diameter. This size is very convenient for the requisite manipulations, and presents a large volume of water, which, when once heated, is capable of preserving a high temperature for a long time. This vessel should be made of wood or copper. It always bears the name of vat. These vats are covered with a wooden lid, divided into two or three equal segments. Over this lid are spread some thick blankets. Without this precaution the bath would come in contact with the atmospheric air, a portion of the indigo would absorb oxygen and become precipitated. There would also be a great waste of heat. A most necessary operation, and one which has to be frequently repeated, consists in stirring up the deposit of vegetable and coloring matter which is formed in the vat, and intimately mixing it in the bath. Eor this purpose we employ a utensil called a rake, which is formed of a strong square piece of wood, set on a long handle. The workman takes hold of this with both hands, and, dipping the flat surface into the deposit at the bottom of the vessel, he quickly draws it up until it nearly reaches the surface, when, giving it a gentle shake, he discharges the matter again through the liquor of the bath. This manoeuvre is repeated until the whole of the deposit seems to be removed from the bottom of the vessel. Before the tissue is dipped into the dye-bath, it should be soaked in a copper full of tepid water ; it is then to be hung up and beaten with sticks. In this state it is plunged into the vat ; it thus introduces less air into the bath, while it is more uniformly penetrated by the indigo solution. The cloth is now kept at a depth of from two to three feet below the surface of the liquid, by means of an open bag or piece of network fixed in the interior of an iron ring, which is suspended by cords, and fixed to the outside of the vat by means of two small iron hooks ; the bag is thus drawn backwards and forwards without permitting it to come in contact with the air. When this operation has been continued for a sufficient length of time, the cloth is wrung and hung up to dry. Flock wool is also, for the purpose of dyeing, enclosed in a fine net, which prevents the least particle from escaping, and which is fixed in the bath in the same way as in the foregoing case. The many inconveniences attending the use of wooden baths, which necessitate the pouring of the liquor into a copper for the purpose of giving it the necessary degree of heat, have led to the general employment of copper vessels. These are fixed in brickwork, which extends half way up their surface, whilst a stove is so constructed at this elevation that the flame shall play around their upper part. By this means the bath is heated and kept at a favorable temperature without the liquor being obliged to be removed. The potash vats are usually formed of conical-shaped coppers, surrounded by a suitable 'furnace. These may be constructed with less depth, inasmuch as there is less precipitation induced in the liquor. By using steam for heating the vats, we might dispense with the employment of copper vessels, and so return to those of wood. Pastel Vat— The first care of the dyer in preparing the vat should be to furnish the bath with matters capable of combining with the oxygen, whether directly or indirectly, and of giving hydrogen to the indigo. We must, however, be careful to employ those substances only which are incapable of imparting to the bath a color which might prove injurious to the indigo. These advantages are found in the pastel, the woad, and madder. This latter substance furnishes a violet tint when brought into contact with an alkali, and by the addition of indigo it yields a still deeper shade. In preparing the Indian vat, we ordinarily employ one pound of fine madder to two pounds of indigo. The madder is here especially useful, by reason of the avidity of some of its principles for oxygen. The pastel vat, when prepared on a large scale, ordinarily contains from 18 to 22 lbs. of indigo ; 11 lbs. of madder would suffice for this proportion, but we must also bear in mind the large quantity of water which we have to charge with oxidizabie matters. I have invariably seen the best results from employ- The distinction between pastel and woad is not very clear. Schutzenberger says: " Pastel, woad, and satis tinctoria is a plant of the family of the crucifera. It would seem, however, that the term pastel as used by the old French dyers is applied to the leaves of the woad which have been fermented, formed into paste, and afterwards into balls, and which contain much blue coloring matter. And the term woad as distinguished from pastel \s applied to the unfermented plant." ing 22 lbs. to a vat of this size. Bran is apt to excite the lactic fermentation tM^ the bath, and should therefore not be employed in too large a quantity; 7 to'fc} lbs. will be found amply sufficient. . y~\ passes into tne putria Termeniauon wiui niumiy. ooiue uyers use il very nueiy ; V* ^ but ordinarily we employ in this bath an equal quantity of it to that of the bran. \ ' Sometimes weld is not added at all. In most dye-houses the pastel is pounded before introducing it into the vat. Some practical men, however, maintain that this operation is injurious, and that it interferes with its durability. This is an opinion which deserves attention. The effect of the pastel, when reduced to a coarse powder, is more uniform ; but this state of division must render its alterations more rapid. When the bath has undergone the necessary ebullition, the pastel should be introduced into the vat, the liquor decanted, and at the same time 7 or 8 lbs. of lime added, so as to form an alkaline lye which shall hold the indigo in solution. Having well stirred the vat, it should be set aside for four hours, so that the little pellets shall have time to become thoroughly soaked, both inside and out, and thus be prepared for fermentation. Some think coverings are to be spread over the vat, so as to preserve it from contact with the atmosphere. After this lapse of time, it is to be again stirred. The bath at this moment presents no decided character ; it has the peculiar odor of the vegetables which it holds in digestion ; its color is of a yellowish-brown. Ordinarily, at the end of twenty -four hours, sometimes even after fifteen or sixteen, the fermentative process is well marked. The odor becomes ammoniacal, at the same time that it retains the peculiar smell of the pastel. The bath, hitherto of a brown color, now assumes a decided yellowish-red tint. A blue froth, which results from the newly liberated indigo of the pastel, floats on the liquor as a thick scum, being composed of small blue bubbles, which are closely agglomerated together. A brilliant pellicle covers the bath, and beneath we may perceive some blue or almost black veins, owing to the indigo of the pastel which rises towards the surface. If the liquor be now agitated with a switch, the small quantity of indigo which is evolved floats to the top of the bath. On exposing a few drops of this mixture to the air, the golden yellow color quickly disappears, and is replaced by the blue tint of the indigo. This phenomenon is due to the absorption of the oxygen of the air by the indigogen from the pastel : in this state we might even dye wool with it without any further addition of indigo ; but the colors which it furnishes are devoid of brilliancy and vivacity of tone, at the same time that the bath becomes quickly exhausted. The signs above described announce, in a most indubitable manner, that fermentation is established, and that the vat has now the power of furnishing to the indigo the hydrogen which is required to render it soluble, — .that contained in the pastel having been already taken up ; this, then, is the proper moment for adding the indigo, which should be previously ground in a mill. We stated above that the liquor of the vat should be previously charged with a certain quantity of lime ; we also find in it ammonia generated by the pastel ; but a part of these alkalies become saturated by the carbonic acid gas along with the proper acids of the madder and of the weld, as well as by the lactic acid produced by the bran during fermentation. The ordinary guide of the dyer is the odor, which, according to circumstances; becomes more or less ammoniacal. The vat is said to be either soft or harsh ; if soft, a little more lime should be added to it. The fresh vat is always soft ; it exhales a feeble ammoniacal odor accompanied with the peculiar smell of the pastel ; we must, therefore, add lime to it along with the indigo ; we usually employ from five to six pounds, and, after having stirred the vat, it is to he covered over. The indigo, being incapable of solution except by its combination with hydrogen, gives no sign of being dissolved until it has remained a certain time in the bath. We may remark that the hard indigoes, as those of Java, require at least eight or nine hours, whilst those of Bengal do not need more than six hours, for their solution. We should examine the vat again three hours after adding the indigo. We ordinarily remark that the odor is by this time weakened ; we must now add a further quantity of lime, sometimes less, but generally about equal in amount to the first portion ; it is then to be covered over again, and set aside for three hours. After this lapse of time, the bath will be found covered with an abundant froth and a very marked copper-colored pellicle ; the veins which float upon its surface are larger and more marked than they were previously ; the liquor becomes of a deep yellowish-red color. On dipping the rake into the bath, and allowing the liquid to run off at the edge, its color, if viewed against the light, is of a strongly marked emerald-green, which gradually disappears, in proportion as the indigo absorbs oxygen, and leaves in its place a mere drop rendered opaque by the blue color of the indigo. The odor of the vat at this instant is strongly ammoniacal ; we also find in it the peculiar scent of the pastel. When we discover a marked character of this kind in the newly formed vat, we may without fear plunge in the stuff intended to be dyed ; but the tints given during the first working of the vat are never so brilliant as those subsequently formed ; this is owing to the yellow-coloring matters of the pastel, which, aided by the heat, become fixed on the wool at the same time as the indigo, and thus give to it a greenish tint. This accident is common both with the pastel and the woad vats ; it is, however, less marked in the latter. When the stuff or cloth has been immersed for an hour in the vat it should be withdrawn; it would, in fact, be useless to leave it there for a longer time, inasmuch as it could absorb no more of the coloring principle. It is therefore to be taken from the bath and hung up to dry, when the indigo, by attracting oxygen, will become insoluble and acquire a blue color. Then we may replunge the stuff in the vat, and the shade will immediately assume a deeper tint, owing to renewed absorption of indigo by the wool. By repeating these operations, we succeed in giving very deep shades. We must not, however, imagine that the cloth seizes only on that portion of indigo contained in the liquor required to soak it. Far from such being the case, experience shows that, during its stay in the bath, it appropriates to itself, within certain limits, a gradually increasing quantity of indigo. We have here, then, an action of affinity, or perhaps a consequence of porosity on the part of the wool itself. Woad Vat. — These vats are extensively employed at Louviers, and in the manufactories of the north of France. The bath is prepared in the same manner as in the foregoing case ; the finely cut root is introduced into the copper along with 2 lbs. of pounded indigo, 9 lbs. of madder, and 15i lbs. of slaked lime. The liquor is, after the necessary ebullition, poured upon the woad. This substance contains but a very small quantity of coloring principle ; we must, therefore, add some indigo when preparing the vat, so as to indicate the precise instant when the mixture arrives at the point of fermentation so necessary for imparting hydrogen to the coloring principle, and for rendering it soluble. We must also use a larger quantity of lime, since the woad contains no ammonia resulting from previous decomposition, such as we find to be the case with the pastel of the south. When the vat is in a suitable state of fermentation, a rusty color becomes manifest, in addition to the signs already described in speaking of the pastel vat ; besides the ammoniacal odor, the bath always retains the peculiar smell of the woad. The pounded indigo is now added, and we proceed, in the manner already detailed, to reduce it to a state of solution fit for dyeing. The vats prepared by means of pastel have greater durability than those made with the woad ; but it is thought that the colors given by the latter are more brilliant than those obtained from the former dye. Modified Pastel Vat. — This vat is about 7 feet in depth, and 6^ feet in diameter. It is made of copper, and heated by steam. The lid is composed of three segments, each of which is formed of two planks, about an inch thick, and strongly secured together by bolts. subsequently repeated. This vat is prepared with 13 lbs. of indigo, 17J lbs. of madder, 4i lbs. of bran, 9 lbs. of lime, and 4J- lbs. of potash. Having filled the vat, we heat it to about 200° Fah., and, as soon as the water is tepid, introduce 441 lbs. of pastel. The liquor becomes of a yellowish-brown color ; small bubbles appear upon its surface, ordinarily at the end of four hours if the vat be heated by steam, but not until after eight or twelve hours where heat is 'applied by the common fire ; in the latter case the mixture should be stirred every three hours. When the liquor displays the signs of fermentation, we add the above-mentioned ingredients, and cover the vat over ; it is then to be set aside, stirring it every three hours, or oftener if the fermentative action be very rapid. Each time that it is stirred we are to add from 2 to 4 lbs. of lime ; if fermentation proceed quickly we even use more, but in the contrary case less. After about eighteen hours, we plunge into the vat three pieces of common cloth, measuring from twenty to twenty-five ells in length each ; when they have received six or seven turns, they are to be taken out again. The object of this is to remove the excess of lime from the bath. The vat is then set aside for three hours, when it is to be stirred, and 13 lbs. of indigo, with 2 lbs. of madder, added to it. We now again apply heat to the mixture. If the vat contains a superabundance of lime, it will be unnecessary to add more ; otherwise we throw in a further quantity. During the night it should be covered with a cloth, and a workman left to watch it. It is usually stirred once before the morning; but if it be deficient in lime, it will require this manipulation to be more frequently repeated, and also fresh lime added to it. On the following day the stirring should be continued every three hours, and so on for the next thirty hours, taking care to heat the vat from time to time. On the morning of the fourth day the dyeing may be commenced. The temperature should be maintained at a pretty uniform point ; if it be too hot, the blue takes a red reflection, by reason of the madder contained in the liquid. A vat thus prepared will last three months ; we may even work it for double that period, but after the third month it appears to lose some of its indigo. We maintain the power of the vat by introducing every night 2£ lbs. of madder. Some indigo is also added twice or three times a week. These additions are made in the evening. After the former, the vat is left at rest for forty-two hours ; with the latter only for twenty-four, at the same time observ- ing the precautions already indicated. At the end of three months, or sooner when we wish to stop the working of the vat, we exhaust the indigo ; for this purpose we continue to charge it every night for the space of a month with madder, and dip into it white cloths, or more particularly woollen tissues, which become more or less loaded with the indigo. We must continue this plan until these matters take up no further color. The dippings are to be performed twice a-day at first, but once only towards the termination. Many dyers make use of this bath for preparing a new vat, but it is better to throw this away and make it up afresh with common water. Indian Vat. — These vats are of more simple and of more ready construction than the pastel or woad vats. We are to boil in water a quantity of madder and of bran, proportioned to the weight of indigo which we wish to employ. After two hours' ebullition, we turn into this bath some tartar-lees, which are also to be boiled for an hour and a half or two hours, so as to charge the bath with whatever soluble matter they may contain ; after this ebullition the bath should be allowed to cool, and the indigo, which has been previously ground, is then to be introduced. Supposing that we wish to employ 21 lbs. of indigo, the following would be the proportions used in preparing this vat : 41 lbs. tartar lees, 13 lbs. of madder, and 5 lbs. of bran. These vats are usually mounted in coppers of a conical shape ; a small fire should be kept up around them, so as to maintain a moderate and uniform heat. The indigo will usually be found dissolved at the end of twenty -four hours, often even after twelve or fifteen hours. The liquor has a reddish color in the new vats, and a green tint in those which are in a working state. The frothy surface, as well as the brilliant-colored pellicle, becomes manifested in this as in all other preparations of a like kind. This species of vat has to be renewed much more frequently than the woad and pastel vats, from the indigo being more difficult to dissolve after a certain lapse of time.' A moderate heat should be maintained in all these vats. Potash Vat. — This species of vat is extensively employed at Elboeuf for the dyeing of wool in the flock. It presents in all respects a perfect analogy with the Indian vat ; in fact, the action of the tartar-lee in the latter preparation depends entirely on the carbonate of potash which it contains. The ingredients used in the preparation of the potash vat are bran, madder, and the subcarbonate of potash of commerce. We obtain the deep shades in this species of vat with greater celerity than in all others, a fact which undoubtedly depends on the greater power which potash has of dissolving indigo than is possessed by lime. Experience proves that the potash vat has the advantage in point of celerity of nearly a third ; but this is balanced by the inconvenience resulting from the darker shade, which we must attribute to the large quantity of coloring matter of the madder dissolved by the alkaline lee, and which becomes fixed on the stuff with the indigo. To render this vat in its most favorable state, the indigo should be made to undergo a commencement of hydrogenation before turning it into the mixture ; for this purpose we prepare in a small copper a bath analogous to that in the vat, to which the pounded indigo is added. This bath is maintained for twenty -four hours at a moderate heat, taking care to stir it from time to time. The indigo assumes a yellowish color, becomes dissolved, and in this state is turned into the vat ; we thus avoid many delays and losses in its preparation, and indeed it would be desirable if a similar plan were adopted with all these compounds. and its depth 8£ feet. Having filled the copper with water, we are to heat it to 200° Fah. ; we then add 20 pailsful of bran, 22 lbs. of carbonate of soda, 11 lbsof indigo, and 5-^ pounds of lime, thoroughly slaked, in powder. The mixture is to be well stirred, and then set aside for two hours ; the workman should continually watch the progress of the fermentation, moderating it more or less by means of lime or carbonate of soda, so as to render the vat in a working state at the end of twelve, fifteen, or, at the most, eighteen hours. The odor is the only criterion by which the workman is enabled to judge of the good state of the vat, he must therefore possess considerable tact and experience. In the process of dipping we introduce 84 lbs., 106 lbs., or even 130 lbs. of wool, in a net bag, similar to that used in the woad vat, taking care that the bag is not allowed to rest against the sides of the copper. When the wool has sufficiently imbibed the color, we remove the bag containing it, and allow it to drain for a short time over the vessel. We operate in this way on two or three quantities in succession ; we then remove the vat, and set it aside for two hours ; we must be careful, from time to time, to replace the indigo absorbed by the wool, as also to add fresh quantities of bran, lime, and crystallized carbonate of soda, so as constantly to maintain the fermentation at a suitable point. The German vat differs, then, from the potash vat by the fact that the potash is replaced by crystallized carbonate of soda and caustic lime, which latter substance also gives to the carbonate of soda a caustic character. It presents a remarkable saving as compared to the potash vat ; hence the frequency of its employment ; but it requires great care, and is more difficult to manage. It also offers considerable economy of labor ; one man is amply sufficient for each vat. The army cloth is usually dyed by means of the pastel vat, which gives the most advantageous results. We here make use of vats about 8-J- feet in depth, and 5 feet in diameter, into which we introduce from 361 lbs. to 405 lbs of pastel or of woad, after previous maceration. The vat is to be filled with boiling water, and we then add to the bath 22 lbs. of madder, 17-J lbs. of weld, and 13 lbs. of bran. The mixture is to maintained in a state of ebullition for about half an hour ; we next add a few pailsful of cold water, taking care, however, not to lower the temperature beyond 130° Fah. ; during the whole of this time a workman, provided with a rake, keeps incessantly stirring the materials of the bath. The vat is then accurately closed by means of a wooden lid, and surrounded by blankets, so as to keep up the heat. It is now put aside for six hours ; after this time it is again stirred by means of a rake, for the space of half an hour; and this operation should be repeated every three hours until the surface of the bath becomes marked with blue veins ; we then add from six to eight pounds of slaked lime. The color of the vat now borders on a blackish-blue. We immediately add the indigo in a quantity proportioned to the shade which we wish to obtain. The pastel in the foregoing mixture may last for several months ; but we must renew the indigo in proportion as it becomes exhausted, at the same time adding both bran and madder. In general we employ — 9 to 11 lbs. of good indigo for 131 yards of cloth dyed in the piece. Management of the Vats. — -A good condition of the vat is recognized by the following characters : The tint of the bath is of a fine golden-yellow, and its surface is covered with a bluish froth and a copper-colored pellicle. On dipping the rake into the bath, there escapes bubbles of air, which should burst very slowly ; when they vanish quickly, it becomes an indication that we must add more lime. The paste which is found at the bottom of the vat, green at the moment of its being drawn up, should become brown in .the air ; if, however, it remains green, this is a further sign that more lime is required. Lastly, the vat should exhale the odor of indigo. We usually complete the assurance of the vat being in a good state by plunging into it, after two hours' respite, a skein of wool, which, on being withdrawn after the lapse of half an hour, should present a green color, but change directly to blue. We then once more mix the materials of the vat, and two hours after it may be considered ready for dyeing. These vats, like those already described, are provided with a large wooden ring, the interior of wiiich is armed with a kind of network, for the purpose of preventing the objects which are intended to be dyed coming in contact with the materials at the bottom of the vat ; we, moreover, take the precaution of enclosing the wool or cloth in bags. These tissues, when plunged into the bath, should remain there for a longer or shorter time, according to the shade which we wish to obtain; one dipping, however, will never suffice for this object; usually we leave in the stuff for half an hour only ; it is then to be taken from the bath, wrung, and exposed to the air. This operation is repeated until we have succeeded in procuring the desired shade ; we ordinarily suffer three hours to elapse between each dipping. The heat of the vat should never be allowed to fall below 130° Fah. After each operation the bath must be well stirred, and. fresh lime added ; generally speaking, a pound a day will suffice. We re-establish the indigo about every second day. When once this vat is well mounted, and we are careful to examine its working, we may dye from two to four batches a day with it. When the stuffs have acquired the desired shade, they are first to be washed in common water, and then in a very weak solution of hydrochloric acid (about one part in a thousand) ; after this they are again rinsed in pure water. The Indian vat is much more easily managed than the foregoing ; it presents less danger of failure, from the fact that it is quickly exhausted, and also from the fermentative process, which is so difficult to govern in the pastel vat ; this vat not having time to change in character. It is prepared by first introducing an equal quantity of madder and of bran, and a triple quantity of potash ; this is to be gradually heated until it reaches a temperature of 167° Fah., and we then add to it the indigo, thoroughly agitating the matters for half an hour. The vat is maintained at a temperature of 86° to 100° Fah., by keeping it. closely covered, and at the same time the mixture is to be stirred occasionally at intervals of twelve hours. It should by this time present a beautiful green shade, the liquor being surmounted by a copper-colored pellicle and a purplish froth. We may now commence the dyeing, following the same course as with the pastel vat ; but the stirrings being here repeated much more frequently than with the other mixture, we can dye a larger quantity of wool within a given time. When the vat ceases to give a brilliant blue, we must altogether renew it; if it be merely weakened, we add to it a small quantity of freshly prepared liquor containing a few pounds of potash, and a little less bran and madder. In giving the dark and the clear sky-blues, we must be careful to employ a quantity of indigo proportioned to the color which we wish to obtain, or, better still, we may use the previously exhausted vat for the dark blue. When exposed to the influence of the putrid fermentation, indigo is decomposed and loses its color. If rendered soluble, it obeys the impulse communicated to the azotized matters with which it is brought into contact, although, if with great difficulty. The pastel and the woad are very prone to the putrid fermentation, by reason of the large quantity of azotized matters which they contain, as do all the cruciferae ; they require therefore considerable care in their employment. When a vat is mounted, if the fermentation be allowed to continue unchecked, after the appearance of the blue froth and the other signs already indicated, the liquor will acquire a yellow color similar to that of beer ; the froth will become white ; it will give out a stale smell and lose its ammoniacal odor ; after a few days it will turn whitish, and exhale a smell at first similar to that of putrefied animal substances ; then it will acquire the odor of rotten eggs, and set free sulphuretted hydrogen. The lime in the pastel and the woad vats, and the tartar-lee and potash in the other mixtures, are used for the purpose of preventing these accidents. Besides the oxygenated compound, which is formed by the combination of oxygen with the extractive matters of the plants held in digestion, there is a production of carbonic acid which saturates the alkaline lee, and forms a carbonate of lime in the pastel vat. We find this attached to the sides of the vat in such quantity that the inside of these vessels becomes incrusted with it to a considerable depth. It is this product which dyers call the tartar of the vat ; it effervesces with acids, and gives on analysis carbonic acid, lime, and a few particles of indigo. In the potash vat the solubility of the carbonate of potash prevents its deposition ; but it is very probable that we have even here a formation of some carbonated products, perhaps in part formed at the expense of the carbonic acid of the air. The soluble extractive principle being the only matter which remains in solution in the bath with the indigo, the lime, &c, we have formed deposits which, varying both in their volume and in the greater or less facility with which they are precipitated during the various periods of fermentation, lead to a more or less considerable waste of time. If we plunge a piece of woollen tissue into a vat which has been recently stirred, it will acquire a dark color, and will be found covered with brown stains which are with difficulty removed. When the woad or paste vat has been stirred, it need be left two or three hours only before plunging in the stuff, at least during the early months of its working, inasmuch as the pastel, being but slightly divided and attenuated, is readily precipitated ; but when, by reason of its extreme division, in consequence of repeated operations, it is thrown down with less facility, the dipping should not be performed oftener than three times in the day. * \| The Indian vat requires less time than the others ; we may even dye with it an hour after stirring the mixture. The potash, being soluble, forms no precipitate ; • while the ligneous fibre of the madder and the pellicles of the bran become deposited with great facility. We can also dip with these vats much oftener than with those made by pastel or woad. REMEDIES. We have to thank that excellent practical magazine, " The American Chemist," for the following notes on the sicknesses of the warm vat, by F. W. Kugler, translated from Reimann's Farberzeintung : — In the wool indigo vat, among the principal " sicknesses " is the blackening of the vat, or " sharpening." This arises from the presence of too much lime. When " sharpened," the liquor, instead of having a waxy yellow color with a dense blue film on its surface, has no film ; while the liquor is a dark blackishgreen, and on being stirred shows a gray or white scum on its surface, while it emits at the same time a pungent odor. If the vat is only slightly affected, it is sufficient to add some bran and madder and to let it stand over night. If it has not quite recovered by morning, it may be necessary to heat it up, agitate it, and let it stand for a couple of hours, after which perhaps the addition of a little lime will be necessary. If the vat is much sharpened, it is recommended to sink in it a bag of bran, and leave it over night, when the fermentation will have restored the vat in a considerable degree ; but it will be necessary to add lime cautiously and by degrees, to bring it to a proper state for working. The theory of the souring of the vat is given. Butyric fermentation takes place under certain circumstances, butyric acid being formed ; and hydrogen is set free, which reduces the indigo. The addition of lime makes the vat too strongly alkaline, and sets ammonia free, which gives the pungent odor of the soured (verschaften) vat. Simultaneously the lime with the white indigo forms a difficultly soluble compound, which settles, and thus interferes with the working of the vat. The excess of lime must be removed, which is accomplished by introducing bran, which causes a lactic fermentation ; and the lactic acid neutralizes the excess of lime, and destroys the lime compound with indigo which had been formed. The lime may be neutralized by the use of mineral acids, but there is danger in that case of precipitating the indigo. veins and surface film disappear on stirring, the foam gives a rustling sound, the bath assumes a reddish-yellow color, blue goods placed in the bath lose their color; and the vat has an unpleasant odor. The vat when "too sweet" needs to be brought to the regular temperature, and lime to be added cautiously until the vat is brought to its normal state. It is safer to add an excess of lime and " sour " the vat, and then bring it back according to the directions under that head, than to add too little, as less indigo is lost. To use up all the dye and to dye a light blue, as little lime should be present as is consistent with the workings of the vat. The cause of the " falling away " of the vat is a too active fermentation, which produces considerable lactic acid, from which butyric acid forms, setting free hydrogen, thereby making white indigo, which, if the action is allowed to continue, changes to a compound from which the indigo cannot be recovered. If lime is added, the lactic and butyric acids unite with it and precipitate it, while the excess precipitates the white indigo, which is slowly recovered, as fermentation progresses, which forms lactic acid, which, taking the place of the white indigo, sets it free. Besides the sicknesses, there are various results of mismanagement, of the beginning of the souring. When the bath begins to sour from overheating, some logwood should be added and then bran, and the vat left to itself over night. The reason of it is that the temperature is too high for the desired fermentation to operate. The vat sometimes suddenly turns green, and even when indigo and the other necessary ingredients are added it remains of this color. This is called the " breaking up of the vat." The reason is that the temperature is too low ; to remedy it, it is necessary to add logwood and bran, warm it up, and stir, when it should stand for some hours.	36,942	common-pile/pre_1929_books_filtered	notesuponindigo00haye	public_library	public_library_1929_dolma-0009.json.gz:4283	https://archive.org/download/notesuponindigo00haye/notesuponindigo00haye_djvu.txt
RCb2kZ-DeIxQcF5D	13.6: Alternative Medical Practices	13.6: Alternative Medical Practices - - Last updated - Save as PDF Complementary and alternative medicine (CAM) is the term for medical products and practices that are not part of standard care. Standard care is what medical doctors, doctors of osteopathy and allied health professionals, such as registered nurses and physical therapists, practice. Alternative medicine means treatments that you use instead of standard ones. Complementary medicine means nonstandard treatments that you use along with standard ones. Examples of CAM therapies are acupuncture, chiropractic and herbal medicines. The claims that CAM treatment providers make about their benefits can sound promising. However, researchers do not know how safe many CAM treatments are or how well they work. Studies are underway to determine the safety and usefulness of many CAM practices. What Is Complementary and Alternative Medicine? Many Americans use complementary and alternative medicine (CAM) in pursuit of health and well-being. The 2007 National Health Interview Survey (NHIS), which included a comprehensive survey of CAM use by Americans, showed that approximately 38 percent of adults use CAM. Defining CAM Defining CAM is difficult, because the field is very broad and constantly changing. NCCAM defines CAM as a group of diverse medical and health care systems, practices, and products that are not generally considered part of conventional medicine. Conventional medicine (also called Western or allopathic medicine) is medicine as practiced by holders of M.D. (medical doctor) and D.O. (doctor of osteopathic medicine) degrees and by allied health professionals, such as physical therapists, psychologists, and registered nurses. The boundaries between CAM and conventional medicine are not absolute, and specific CAM practices may, over time, become widely accepted. "Complementary medicine" refers to use of CAM together with conventional medicine, such as using acupuncture in addition to usual care to help lessen pain. Most use of CAM by Americans is complementary. "Alternative medicine" refers to use of CAM in place of conventional medicine. "Integrative medicine" combines treatments from conventional medicine and CAM for which there is some high-quality evidence of safety and effectiveness. It is also called integrated medicine. Types of CAM CAM practices are often grouped into broad categories, such as natural products, mind and body medicine, and manipulative and body-based practices. Although these categories are not formally defined, they are useful for discussing CAM practices. Some CAM practices may fit into more than one category. Natural Products This area of CAM includes use of a variety of herbal medicines (also known as botanicals), vitamins, minerals, and other "natural products." Many are sold over the counter as dietary supplements. (Some uses of dietary supplements—e.g., taking a multivitamin to meet minimum daily nutritional requirements or taking calcium to promote bone health—are not thought of as CAM.) CAM "natural products" also include probiotics—live microorganisms (usually bacteria) that are similar to microorganisms normally found in the human digestive tract and that may have beneficial effects. Probiotics are available in foods (e.g., yogurts) or as dietary supplements. They are not the same thing as prebiotics — nondigestible food ingredients that selectively stimulate the growth and/or activity of microorganisms already present in the body. Interest in and use of CAM natural products have grown considerably in the past few decades. The 2007 NHIS found that 17.7 percent of American adults had used a nonvitamin/nonmineral natural product. These products were the most popular form of CAM among both adults and children. The most commonly used product among adults was fish oil/omega 3s (reported by 37.4 percent of all adults who said they used natural products); popular products for children included echinacea (37.2 percent) and fish oil/omega 3s (30.5 percent). Figure $\PageIndex{1}$. NIH Mind and Body Medicine Mind and body practices focus on the interactions among the brain, mind, body, and behavior, with the intent to use the mind to affect physical functioning and promote health. Many CAM practices embody this concept—in different ways. - Meditation techniques include specific postures, focused attention, or an open attitude toward distractions. People use meditation to increase calmness and relaxation, improve psychological balance, cope with illness, or enhance overall health and well-being. - The various styles of yoga used for health purposes typically combine physical postures, breathing techniques, and meditation or relaxation. People use yoga as part of a general health regimen, and also for a variety of health conditions. - Acupuncture is a family of procedures involving the stimulation of specific points on the body using a variety of techniques, such as penetrating the skin with needles that are then manipulated by hand or by electrical stimulation. It is one of the key components of traditional Chinese medicine, and is among the oldest healing practices in the world. Other examples of mind and body practices include deep-breathing exercises, guided imagery, hypnotherapy, progressive relaxation, qi gong, and tai chi . Historical note: The concept that the mind is important in the treatment of illness is integral to the healing approaches of traditional Chinese medicine and Ayurvedic medicine, dating back more than 2,000 years. Hippocrates also noted the moral and spiritual aspects of healing and believed that treatment could occur only with consideration of attitude, environmental influences, and natural remedies. Current use: Several mind and body approaches ranked among the top 10 CAM practices reported by adults in the 2007 NHIS. For example, the survey found that 12.7 percent of adults had used deep-breathing exercises, 9.4 percent had practiced meditation, and 6.1 percent had practiced yoga; use of these three CAM practices had increased significantly since the previous (2002) NHIS. Progressive relaxation and guided imagery were also among the top 10 CAM therapies for adults; deep breathing and yoga ranked high among children. Acupuncture had been used by 1.4 percent of adults and 0.2 percent of children. Acupuncture is considered to be a part of mind and body medicine, but it is also a component of energy medicine, manipulative and body-based practices, and traditional Chinese medicine. Manipulative and Body-Based Practices Manipulative and body-based practices focus primarily on the structures and systems of the body, including the bones and joints, soft tissues, and circulatory and lymphatic systems. Two commonly used therapies fall within this category: - Spinal manipulation is performed by chiropractors and by other health care professionals such as physical therapists, osteopathic physicians, and some conventional medical doctors. Practitioners use their hands or a device to apply a controlled force to a joint of the spine, moving it beyond its passive range of motion; the amount of force applied depends on the form of manipulation used. Spinal manipulation is among the treatment options used by people with low-back pain - a very common condition that can be difficult to treat. - The term massage therapy encompasses many different techniques. In general, therapists press, rub, and otherwise manipulate the muscles and other soft tissues of the body. People use massage for a variety of health-related purposes, including to relieve pain, rehabilitate sports injuries, reduce stress, increase relaxation, address anxiety and depression, and aid general well-being. Other CAM Practices CAM also encompasses movement therapies —a broad range of Eastern and Western movement-based approaches used to promote physical, mental, emotional, and spiritual well-being. Examples include Feldenkrais method, Alexander technique, Pilates, Rolfing Structural Integration, and Trager psychophysical integration. According to the 2007 NHIS, 1.5 percent of adults and 0.4 percent of children used movement therapies. Practices of traditional healers can also be considered a form of CAM. Traditional healers use methods based on indigenous theories, beliefs, and experiences handed down from generation to generation. A familiar example in the United States is the Native American healer/medicine man. The 2007 NHIS found that 0.4 percent of adults and 1.1 percent of children had used a traditional healer (usage varied for the seven specific types of healers identified in the survey). Some CAM practices involve manipulation of various energy fields to affect health. Such fields may be characterized as veritable (measurable) or putative (yet to be measured). Practices based on veritable forms of energy include those involving electromagnetic fields (e.g., magnet therapy and light therapy). Practices based on putative energy fields (also called biofields) generally reflect the concept that human beings are infused with subtle forms of energy; qi gong, Reiki, and healing touch are examples of such practices. The 2007 NHIS found relatively low use of putative energy therapies. Only 0.5 percent of adults and 0.2 percent of children had used energy healing/Reiki (the survey defined energy healing as the channeling of healing energy through the hands of a practitioner into the client's body). Finally, whole medical systems, which are complete systems of theory and practice that have evolved over time in different cultures and apart from conventional or Western medicine, may be considered CAM. Examples of ancient whole medical systems include Ayurvedic medicine and traditional Chinese medicine. More modern systems that have developed in the past few centuries include homeopathy and naturopathy. The 2007 NHIS asked about the use of Ayurveda, homeopathy, and naturopathy. Although relatively few respondents said they had used Ayurveda or naturopathy, homeopathy ranked 10th in usage among adults (1.8 percent) and 5th among children (1.3 percent). Health Fraud You have probably seen ads for miracle cures - a supplement to cure cancer, a diet to cure diabetes. But remember - if it sounds too good to be true, then it probably is. Health fraud involves selling drugs, devices, foods or cosmetics that have not been proven effective. At best, these scams don't work. At worst, they're dangerous. They also waste money, and they might keep you from getting the treatment you really need. Health scams often target older people. Most victims in the United States are older than 65. To protect yourself - Question claims of miracle cures or breakthroughs - Know that newspapers, magazines, and radio and TV stations do not have to make sure that the ads they run are true - Find out about products before you buy them - Don't let salespeople force you into making snap decisions - Check with your doctor before taking products Beware of Health Scams You see the ads everywhere these days — “Smart Drugs” for long life or “Arthritis Aches and Pains Disappear Like Magic!” or even statements claiming, “This treatment cured my cancer in 1 week.” It’s easy to understand the appeal of these promises. But there is still plenty of truth to the old saying, “If it sounds too good to be true, it probably is!” Health scams and the marketing of unproven cures have been around for many years. Today, there are more ways than ever to sell these untested products. In addition to TV, radio, magazines, newspapers, infomercials, mail, telemarketing, and even word-of-mouth, these products are now offered over the Internet—with websites describing miracle cures and emails telling stories of overnight magic. Sadly, older people are often the target of such scams. The problem is serious. Untested remedies may be harmful. They may get in the way of medicines prescribed by your doctor. They may also waste money. And, sometimes, using these products keeps people from getting the medical treatment they need. False Hopes Why do people fall for these sales pitches? Unproven remedies promise false hope. They offer cures that appear to be painless or quick. At best, these treatments are worthless. At worst, they are dangerous. Health scams prey on people who are frightened or in pain. Living with a chronic health problem is hard. It’s easy to see why people might fall for a false promise of a quick and painless cure. The best way for scientists to find out if a treatment works is through a clinical trial. How Can You Protect Yourself From Health Scams? Be wary. Question what you see or hear in ads or on the Internet. Newspapers, magazines, radio, and TV stations do not always check to make sure the claims in their ads are true. Find out about a product before you buy. Don’t let a salesperson talk you into making a snap decision. Check with your healthcare provider first. - Promise a quick or painless cure - Claim the product is made from a special, secret, or ancient formula - Offer products and services only by mail or from one company - Use statements or unproven case histories from so-called satisfied patients - Claim to be a cure for a wide range of ailments - Claim to cure a disease (such as arthritis or Alzheimer’s disease) that hasn’t been cured by medical science - Promise a no-risk, money-back guarantee - Offer an additional “free” gift or a larger amount of the product as a “special promotion” - Require advance payment and claim there is a limited supply of the product	2,737	common-pile/libretexts_filtered	https://med.libretexts.org/Courses/Chabot_College/Introduction_to_Health/13%3A_Health_Care_Choices/13.06%3A_Alternative_Medical_Practices	libretexts	libretexts-0000.json.gz:28644	https://med.libretexts.org/Courses/Chabot_College/Introduction_to_Health/13%3A_Health_Care_Choices/13.06%3A_Alternative_Medical_Practices
L2biH9F4iD2ykC-E	Identifying OER Needs for High Enrollment Classes with Costly Textbooks	Castiglione, J. (2008). Environmental scanning: an essential tool for twenty‐first century librarianship. Library Review, 57(7), 528–536. https://doi.org/10.1108/00242530810894040 Facts and Figures. UC Santa Barbara. (n.d.). https://www.ucsb.edu/about/facts-and-figures. General Collection Development Policy. UCSB Library. (2019, April 25). https://www.library.ucsb.edu/collection-development/general-policy#:~:text=The%20goal%20of%20collection%20development,of%20the%20UCSB%20academic%20community. Home. Promise Scholars. (n.d.). https://promisescholars.sa.ucsb.edu/. Lederman, D. (2021). Pandemic didn’t speed adoption of open educational resources, but outlook is promising. Inside Higher Ed. https://www.insidehighered.com/digital-learning/article/2021/03/18/pandemic-didnt-speed-adoption-open-educational-resources-outlook#.YFPJA2b69tU.link. Open Education. Hewlett Foundation. https://hewlett.org/strategy/open-education/. Open Education Resources (OER): Home. LibGuides. (n.d.). https://guides.library.ucsb.edu/open-education-resources. Schroeder, R. (n.d.). It’s Time for Open Educational Resources. Inside Higher Ed. https://www.insidehighered.com/digital-learning/blogs/online-trending-now/it%E2%80%99s-time-open-educational-resources. SPARC (2018). Open Education Primer An Introduction to Open Educational Resources, Practices and Policy for Academic Libraries. Attribution 4.0 International, https://sparcopen.org/leadership-program UC Santa Barbara Office of the Registrar. 2020-2021 Quarterly Fees and Expenses – UCSB Office of the Registrar. (n.d.). https://registrar.sa.ucsb.edu/fees-residency/fee-information/2020-2021-quarterly-fees-and-expenses. Who We Are. SPARC. (n.d.). https://sparcopen.org/who-we-are/.	171	common-pile/pressbooks_filtered	https://pressbooks.pub/ucsblibraryoerenvironmentalscan/chapter/references/	pressbooks	pressbooks-0000.json.gz:5390	https://pressbooks.pub/ucsblibraryoerenvironmentalscan/chapter/references/
4oyo03f1zW8_YHox	7: Cellular Respiration	7: Cellular Respiration Like a generating plant, plants and animals also must take in energy from the environment and convert it into a form that their cells can use. Energy enters an organism’s body in one form and is converted into another form that can fuel the organism’s life functions. In the process of photosynthesis, plants and other photosynthetic producers take in energy in the form of light (solar energy) and convert it into chemical energy, glucose, which stores this energy in its chemical bonds. Then, a series of metabolic pathways, collectively called cellular respiration, extracts the energy from the bonds in glucose and converts it into a form that all living things can use—both producers, such as plants, and consumers, such as animals. - - 7.0: Prelude to Cellular Respiration - Energy enters an organism’s body in one form and is converted into another form that can fuel the organism’s life functions. A series of metabolic pathways, collectively called cellular respiration, extracts the energy from the bonds in glucose and converts it into a form that all living things can use—both producers, such as plants, and consumers, such as animals. - - 7.1: Energy in Living Systems - Energy production within a cell involves many coordinated chemical pathways. Most of these pathways are combinations of oxidation and reduction reactions. Oxidation and reduction occur in tandem. An oxidation reaction strips an electron from an atom in a compound, and the addition of this electron to another compound is a reduction reaction. Because oxidation and reduction usually occur together, these pairs of reactions are called oxidation reduction reactions, or redox reactions. - - 7.2: Glycolysis - Glycolysis is the first step in the breakdown of glucose to extract energy for cellular metabolism. Nearly all living organisms carry out glycolysis as part of their metabolism. The process does not use oxygen and is therefore anaerobic. Glycolysis takes place in the cytoplasm of both prokaryotic and eukaryotic cells. - - 7.3: Oxidation of Pyruvate and the Citric Acid Cycle - If oxygen is available, aerobic respiration will go forward. In eukaryotic cells, the pyruvate molecules produced at the end of glycolysis are transported into mitochondria, which are the sites of cellular respiration. There, pyruvate will be transformed into an acetyl group that will be picked up and activated by a carrier compound called coenzyme A (CoA). The resulting compound is called acetyl CoA. CoA is made from vitamin B5, pantothenic acid. - - 7.4: Oxidative Phosphorylation - You have just read about two pathways in glucose catabolism—glycolysis and the citric acid cycle—that generate ATP. Most of the ATP generated during the aerobic catabolism of glucose, however, is not generated directly from these pathways. Rather, it is derived from a process that begins with moving electrons through a series of electron transporters that undergo redox reactions. This causes hydrogen ions to accumulate within the matrix space. - - 7.5: Metabolism without Oxygen - In aerobic respiration, the final electron acceptor is an oxygen molecule, O2. If aerobic respiration occurs, then ATP will be produced using the energy of high-energy electrons carried by NADH or FADH2 to the electron transport chain. If aerobic respiration does not occur, NADH must be reoxidized to NAD+ for reuse as an electron carrier for the glycolytic pathway to continue. - - 7.6: Connections of Carbohydrate, Protein, and Lipid Metabolic Pathways - All of the catabolic pathways for carbohydrates, proteins, and lipids eventually connect into glycolysis and the citric acid cycle pathways. Metabolic pathways should be thought of as porous—that is, substances enter from other pathways, and intermediates leave for other pathways. These pathways are not closed systems. Many of the substrates, intermediates, and products in a particular pathway are reactants in other pathways. - - 7.7: Regulation of Cellular Respiration - Cellular respiration must be regulated in order to provide balanced amounts of energy in the form of ATP. The cell also must generate a number of intermediate compounds that are used in the anabolism and catabolism of macromolecules. Without controls, metabolic reactions would quickly come to a stand still as the forward and backward reactions reached a state of equilibrium. Resources would be used inappropriately. Thumbnail: The generalized structure of a prokaryotic cell. (CC BY 4.0; OpenStax ).	923	common-pile/libretexts_filtered	https://bio.libretexts.org/Bookshelves/Introductory_and_General_Biology/General_Biology_1e_(OpenStax)/2%3A_The_Cell/07%3A_Cellular_Respiration	libretexts	libretexts-0000.json.gz:24345	https://bio.libretexts.org/Bookshelves/Introductory_and_General_Biology/General_Biology_1e_(OpenStax)/2%3A_The_Cell/07%3A_Cellular_Respiration
MagXrFwt1QwKVqfj	7.2: The Viral Life Cycle	7.2: The Viral Life Cycle - - Last updated - Save as PDF - Ying Liu - City College of San Francisco Learning Objectives - Describe the lytic and lysogenic life cycles - Describe the replication process of animal viruses - Describe unique characteristics of retroviruses and latent viruses - Discuss human viruses and their virus-host cell interactions - Explain the process of transduction - Describe the replication process of plant viruses All viruses depend on cells for reproduction and metabolic processes. By themselves, viruses do not encode for all of the enzymes necessary for viral replication. But within a host cell, a virus can commandeer cellular machinery to produce more viral particles. Bacteriophages replicate only in the cytoplasm, since prokaryotic cells do not have a nucleus or organelles. In eukaryotic cells, most DNA viruses can replicate inside the nucleus, with an exception observed in the large DNA viruses, such as the poxviruses, that can replicate in the cytoplasm. RNA viruses that infect animal cells often replicate in the cytoplasm. The Life Cycle of Viruses with Prokaryote Hosts The life cycle of bacteriophages has been a good model for understanding how viruses affect the cells they infect, since similar processes have been observed for eukaryotic viruses, which can cause immediate death of the cell or establish a latent or chronic infection. Virulent phages typically lead to the death of the cell through cell lysis. Temperate phages , on the other hand, can become part of a host chromosome and are replicated with the cell genome until such time as they are induced to make newly assembled viruses, or progeny viruses . The Lytic Cycle During the lytic cycle of virulent phage, the bacteriophage takes over the cell, reproduces new phages, and destroys the cell. T-even phage is a good example of a well-characterized class of virulent phages. There are five stages in the bacteriophage lytic cycle (see Figure $\PageIndex{1}$). Attachment is the first stage in the infection process in which the phage interacts with specific bacterial surface receptors (e.g., lipopolysaccharides and OmpC protein on host surfaces). Most phages have a narrow host range and may infect one species of bacteria or one strain within a species. This unique recognition can be exploited for targeted treatment of bacterial infection by phage therapy or for phage typing to identify unique bacterial subspecies or strains. The second stage of infection is entry or penetration. This occurs through contraction of the tail sheath, which acts like a hypodermic needle to inject the viral genome through the cell wall and membrane. The phage head and remaining components remain outside the bacteria. The third stage of infection is biosynthesis of new viral components. After entering the host cell, the virus synthesizes virus-encoded endonucleases to degrade the bacterial chromosome. It then hijacks the host cell to replicate, transcribe, and translate the necessary viral components (capsomeres, sheath, base plates, tail fibers, and viral enzymes) for the assembly of new viruses. Polymerase genes are usually expressed early in the cycle, while capsid and tail proteins are expressed later. During the maturation phase, new virions are created. To liberate free phages, the bacterial cell wall is disrupted by phage proteins such as holin or lysozyme. The final stage is release. Mature viruses burst out of the host cell in a process called lysis and the progeny viruses are liberated into the environment to infect new cells. The Lysogenic Cycle In a lysogenic cycle, the phage genome also enters the cell through attachment and penetration. A prime example of a phage with this type of life cycle is the lambda phage. During the lysogenic cycle, instead of killing the host, the phage genome integrates into the bacterial chromosome and becomes part of the host. The integrated phage genome is called a prophage. A bacterial host with a prophage is called a lysogen. The process in which a bacterium is infected by a temperate phage is called lysogeny. It is typical of temperate phages to be latent or inactive within the cell. As the bacterium replicates its chromosome, it also replicates the phage’s DNA and passes it on to new daughter cells during reproduction. The presence of the phage may alter the phenotype of the bacterium, since it can bring in extra genes (e.g., toxin genes that can increase bacterial virulence). This change in the host phenotype is called lysogenic conversion or phage conversion. Some bacteria, such as Vibrio cholerae and Clostridium botulinum , are less virulent in the absence of the prophage. The phages infecting these bacteria carry the toxin genes in their genome and enhance the virulence of the host when the toxin genes are expressed. In the case of V. cholera , phage encoded toxin can cause severe diarrhea; in C. botulinum , the toxin can cause paralysis. During lysogeny, the prophage will persist in the host chromosome until induction, which results in the excision of the viral genome from the host chromosome. After induction has occurred the temperate phage can proceed through a lytic cycle and then undergo lysogeny in a newly infected cell (see Figure $\PageIndex{2}$). Link to Learning This video illustrates the stages of the lysogenic life cycle of a bacteriophage and the transition to a lytic phase. Exercise $\PageIndex{1}$ Is a latent phage undetectable in a bacterium? Transduction Transduction occurs when a bacteriophage transfers bacterial DNA from one bacterium to another during sequential infections. There are two types of transduction: generalized and specialized transduction. During the lytic cycle of viral replication, the virus hijacks the host cell, degrades the host chromosome, and makes more viral genomes. As it assembles and packages DNA into the phage head, packaging occasionally makes a mistake. Instead of packaging viral DNA, it takes a random piece of host DNA and inserts it into the capsid. Once released, this virion will then inject the former host’s DNA into a newly infected host. The asexual transfer of genetic information can allow for DNA recombination to occur, thus providing the new host with new genes (e.g., an antibiotic-resistance gene, or a sugar-metabolizing gene). Generalized transduction occurs when a random piece of bacterial chromosomal DNA is transferred by the phage during the lytic cycle. Specialized transduction occurs at the end of the lysogenic cycle, when the prophage is excised and the bacteriophage enters the lytic cycle. Since the phage is integrated into the host genome, the prophage can replicate as part of the host. However, some conditions (e.g., ultraviolet light exposure or chemical exposure) stimulate the prophage to undergo induction, causing the phage to excise from the genome, enter the lytic cycle, and produce new phages to leave host cells. During the process of excision from the host chromosome, a phage may occasionally remove some bacterial DNA near the site of viral integration. The phage and host DNA from one end or both ends of the integration site are packaged within the capsid and are transferred to the new, infected host. Since the DNA transferred by the phage is not randomly packaged but is instead a specific piece of DNA near the site of integration, this mechanism of gene transfer is referred to as specialized transduction (see Figure $\PageIndex{3}$). The DNA can then recombine with host chromosome, giving the latter new characteristics. Transduction seems to play an important role in the evolutionary process of bacteria, giving them a mechanism for asexual exchange of genetic information. Exercise $\PageIndex{2}$ Which phage life cycle is associated with which forms of transduction? Life Cycle of Viruses with Animal Hosts Lytic animal viruses follow similar infection stages to bacteriophages: attachment, penetration, biosynthesis, maturation, and release (see Figure $\PageIndex{4}$). However, the mechanisms of penetration, nucleic-acid biosynthesis, and release differ between bacterial and animal viruses. After binding to host receptors, animal viruses enter through endocytosis(engulfment by the host cell) or through membrane fusion (viral envelope with the host cell membrane). Many viruses are host specific, meaning they only infect a certain type of host; and most viruses only infect certain types of cells within tissues. This specificity is called a tissue tropism. Examples of this are demonstrated by the poliovirus, which exhibits tropism for the tissues of the brain and spinal cord, or the influenza virus, which has a primary tropism for the respiratory tract. Animal viruses do not always express their genes using the normal flow of genetic information—from DNA to RNA to protein. Some viruses have a dsDNA genome like cellular organisms and can follow the normal flow. However, others may have ssDNA, dsRNA, or ssRNA genomes. The nature of the genome determines how the genome is replicated and expressed as viral proteins. If a genome is ssDNA, host enzymes will be used to synthesize a second strand that is complementary to the genome strand, thus producing dsDNA. The dsDNA can now be replicated, transcribed, and translated similar to host DNA. If the viral genome is RNA, a different mechanism must be used. There are three types of RNA genome: dsRNA, positive (+) single-strand (+ssRNA) or negative (−) single-strand RNA (−ssRNA). If a virus has a +ssRNA genome, it can be translated directly to make viral proteins. Viral genomic +ssRNA acts like cellular mRNA. However, if a virus contains a −ssRNA genome, the host ribosomes cannot translate it until the −ssRNA is replicated into +ssRNA by viral RNA-dependent RNA polymerase (RdRP) (see Figure $\PageIndex{5}$). The RdRP is brought in by the virus and can be used to make +ssRNA from the original −ssRNA genome. The RdRP is also an important enzyme for the replication of dsRNA viruses, because it uses the negative strand of the double-stranded genome as a template to create +ssRNA. The newly synthesized +ssRNA copies can then be translated by cellular ribosomes. An alternative mechanism for viral nucleic acid synthesis is observed in the retrovirus es , which are +ssRNA viruses (see Figure $\PageIndex{6}$). Single-stranded RNA viruses such as HIV carry a special enzyme called reverse transcriptase within the capsid that synthesizes a complementary ssDNA (cDNA) copy using the +ssRNA genome as a template. The ssDNA is then made into dsDNA, which can integrate into the host chromosome and become a permanent part of the host. The integrated viral genome is called a provirus. The virus now can remain in the host for a long time to establish a chronic infection. The provirus stage is similar to the prophage stage in a bacterial infection during the lysogenic cycle. However, unlike prophage, the provirus does not undergo excision after splicing into the genome. Exercise $\PageIndex{3}$ Is RNA-dependent RNA polymerase made from a viral gene or a host gene? Persistent Infections Persistent infection occurs when a virus is not completely cleared from the system of the host but stays in certain tissues or organs of the infected person. The virus may remain silent or undergo productive infection without seriously harming or killing the host. Mechanisms of persistent infection may involve the regulation of the viral or host gene expressions or the alteration of the host immune response. The two primary categories of persistent infections are latent infection and chronic infection. Examples of viruses that cause latent infections include herpes simplex virus (oral and genital herpes), varicella-zoster virus (chickenpox and shingles), and Epstein-Barr virus (mononucleosis). Hepatitis C virus and HIV are two examples of viruses that cause long-term chronic infections. Latent Infection Not all animal viruses undergo replication by the lytic cycle. There are viruses that are capable of remaining hidden or dormant inside the cell in a process called latency. These types of viruses are known as latent virus es and may cause latent infections. Viruses capable of latency may initially cause an acute infection before becoming dormant. For example, the varicella-zoster virus infects many cells throughout the body and causes chickenpox, characterized by a rash of blisters covering the skin. About 10 to 12 days postinfection, the disease resolves and the virus goes dormant, living within nerve-cell ganglia for years. It is not clear why the virus stops replicating within the nerve cells and expresses few viral proteins but, in some cases, typically after many years of dormancy, the virus is reactivated and causes a new disease called shingles (Figure $\PageIndex{7}$). Whereas chickenpox affects many areas throughout the body, shingles is a nerve cell-specific disease emerging from the ganglia in which the virus was dormant. Latent viruses may remain dormant by existing as circular viral genome molecules outside of the host chromosome. Others become proviruses by integrating into the host genome. During dormancy, viruses do not cause any symptoms of disease and may be difficult to detect. A patient may be unaware that he or she is carrying the virus unless a viral diagnostic test has been performed. Chronic Infection A chronic infection is a disease with symptoms that are recurrent or persistent over a long time. Some viral infections can be chronic if the body is unable to eliminate the virus. HIV is an example of a virus that produces a chronic infection, often after a long period of latency. Once a person becomes infected with HIV, the virus can be detected in tissues continuously thereafter, but untreated patients often experience no symptoms for years. However, the virus maintains chronic persistence through several mechanisms that interfere with immune function, including preventing expression of viral antigens on the surface of infected cells, altering immune cells themselves, restricting expression of viral genes, and rapidly changing viral antigens through mutation. Eventually, the damage to the immune system results in progression of the disease leading to acquired immunodeficiency syndrome (AIDS). The various mechanisms that HIV uses to avoid being cleared by the immune system are also used by other chronically infecting viruses, including the hepatitis C virus. Exercise $\PageIndex{4}$ In what two ways can a virus manage to maintain a persistent infection? Life Cycle of Viruses with Plant Hosts Plant viruses are more similar to animal viruses than they are to bacteriophages. Plant viruses may be enveloped or non-enveloped. Like many animal viruses, plant viruses can have either a DNA or RNA genome and be single stranded or double stranded. However, most plant viruses do not have a DNA genome; the majority have a +ssRNA genome, which acts like messenger RNA (mRNA). Only a minority of plant viruses have other types of genomes. Plant viruses may have a narrow or broad host range. For example, the citrus tristeza virus infects only a few plants of the Citrus genus, whereas the cucumber mosaic virus infects thousands of plants of various plant families. Most plant viruses are transmitted by contact between plants, or by fungi, nematodes, insects, or other arthropods that act as mechanical vectors. However, some viruses can only be transferred by a specific type of insect vector; for example, a particular virus might be transmitted by aphids but not whiteflies. In some cases, viruses may also enter healthy plants through wounds, as might occur due to pruning or weather damage. Viruses that infect plants are considered biotrophic parasites, which means that they can establish an infection without killing the host, similar to what is observed in the lysogenic life cycles of bacteriophages. Viral infection can be asymptomatic (latent) or can lead to cell death (lytic infection). The life cycle begins with the penetration of the virus into the host cell. Next, the virus is uncoated within the cytoplasm of the cell when the capsid is removed. Depending on the type of nucleic acid, cellular components are used to replicate the viral genome and synthesize viral proteins for assembly of new virions. To establish a systemic infection, the virus must enter a part of the vascular system of the plant, such as the phloem. The time required for systemic infection may vary from a few days to a few weeks depending on the virus, the plant species, and the environmental conditions. The virus life cycle is complete when it is transmitted from an infected plant to a healthy plant. Exercise $\PageIndex{5}$ What is the structure and genome of a typical plant virus? Viral Growth Curve Unlike the growth curve for a bacterial population, the growth curve for a virus population over its life cycle does not follow a sigmoidal curve. During the initial stage, an inoculum of virus causes infection. In the eclipse phase, viruses bind and penetrate the cells with no virions detected in the medium. The chief difference that next appears in the viral growth curve compared to a bacterial growth curve occurs when virions are released from the lysed host cell at the same time. Such an occurrence is called a burst, and the number of virions per bacterium released is described as the burst size. In a one-step multiplication curve for bacteriophage, the host cells lyse, releasing many viral particles to the medium, which leads to a very steep rise in viral titer (the number of virions per unit volume). If no viable host cells remain, the viral particles begin to degrade during the decline of the culture (see Figure $\PageIndex{8}$). Exercise $\PageIndex{6}$ What aspect of the life cycle of a virus leads to the sudden increase in the growth curve? Unregistered Treatments Ebola is incurable and deadly. The outbreak in West Africa in 2014 was unprecedented, dwarfing other human Ebola epidemics in the level of mortality. Of 24,666 suspected or confirmed cases reported, 10,179 people died. 1 No approved treatments or vaccines for Ebola are available. While some drugs have shown potential in laboratory studies and animal models, they have not been tested in humans for safety and effectiveness. Not only are these drugs untested or unregistered but they are also in short supply. Given the great suffering and high mortality rates, it is fair to ask whether unregistered and untested medications are better than none at all. Should such drugs be dispensed and, if so, who should receive them, in light of their extremely limited supplies? Is it ethical to treat untested drugs on patients with Ebola? On the other hand, is it ethical to withhold potentially life-saving drugs from dying patients? Or should the drugs perhaps be reserved for health-care providers working to contain the disease? In August 2014, two infected US aid workers and a Spanish priest were treated with ZMapp, an unregistered drug that had been tested in monkeys but not in humans. The two American aid workers recovered, but the priest died. Later that month, the WHO released a report on the ethics of treating patients with the drug. Since Ebola is often fatal, the panel reasoned that it is ethical to give the unregistered drugs and unethical to withhold them for safety concerns. This situation is an example of “compassionate use” outside the well-established system of regulation and governance of therapies. Ebola in the US On September 24, 2014, Thomas Eric Duncan arrived at the Texas Health Presbyterian Hospital in Dallas complaining of a fever, headache, vomiting, and diarrhea—symptoms commonly observed in patients with the cold or the flu. After examination, an emergency department doctor diagnosed him with sinusitis, prescribed some antibiotics, and sent him home. Two days later, Duncan returned to the hospital by ambulance. His condition had deteriorated and additional blood tests confirmed that he has been infected with the Ebola virus. Further investigations revealed that Duncan had just returned from Liberia, one of the countries in the midst of a severe Ebola epidemic. On September 15, nine days before he showed up at the hospital in Dallas, Duncan had helped transport an Ebola-stricken neighbor to a hospital in Liberia. The hospital continued to treat Duncan, but he died several days after being admitted. The timeline of the Duncan case is indicative of the life cycle of the Ebola virus. The incubation time for Ebola ranges from 2 days to 21 days. Nine days passed between Duncan’s exposure to the virus infection and the appearance of his symptoms. This corresponds, in part, to the eclipse period in the growth of the virus population. During the eclipse phase, Duncan would have been unable to transmit the disease to others. However, once an infected individual begins exhibiting symptoms, the disease becomes very contagious. Ebola virus is transmitted through direct contact with droplets of bodily fluids such as saliva, blood, and vomit. Duncan could conceivably have transmitted the disease to others at any time after he began having symptoms, presumably some time before his arrival at the hospital in Dallas. Once a hospital realizes a patient like Duncan is infected with Ebola virus, the patient is immediately quarantined, and public health officials initiate a back trace to identify everyone with whom a patient like Duncan might have interacted during the period in which he was showing symptoms. Public health officials were able to track down 10 high-risk individuals (family members of Duncan) and 50 low-risk individuals to monitor them for signs of infection. None contracted the disease. However, one of the nurses charged with Duncan’s care did become infected. This, along with Duncan’s initial misdiagnosis, made it clear that US hospitals needed to provide additional training to medical personnel to prevent a possible Ebola outbreak in the US. Exercise $\PageIndex{7}$ - What types of training can prepare health professionals to contain emerging epidemics like the Ebola outbreak of 2014? - What is the difference between a contagious pathogen and an infectious pathogen? Summary - Many viruses target specific hosts or tissues. Some may have more than one host. - Many viruses follow several stages to infect host cells. These stages include attachment, penetration, uncoating, biosynthesis, maturation, and release . - Bacteriophages have a lytic or lysogenic cycle . The lytic cycle leads to the death of the host, whereas the lysogenic cycle leads to integration of phage into the host genome. - Bacteriophages inject DNA into the host cell, whereas animal viruses enter by endocytosis or membrane fusion. - Animal viruses can undergo latency , similar to lysogeny for a bacteriophage. - The majority of plant viruses are positive-strand ssRNA and can undergo latency, chronic, or lytic infection, as observed for animal viruses. - The growth curve of bacteriophage populations is a one-step multiplication curve and not a sigmoidal curve, as compared to the bacterial growth curve. - Bacteriophages transfer genetic information between hosts using either generalized or specialized transduction . Footnotes - 1 World Health Organization. “WHO Ebola Data and Statistics.” March 18, 2005. http://apps.who.int/gho/data/view.eb...150318?lang=en	4,829	common-pile/libretexts_filtered	https://bio.libretexts.org/Courses/North_Central_State_College/BIOL_1550%3A_Microbiology_(2025)/07%3A_Viruses/7.02%3A_The_Viral_Life_Cycle	libretexts	libretexts-0000.json.gz:10465	https://bio.libretexts.org/Courses/North_Central_State_College/BIOL_1550%3A_Microbiology_(2025)/07%3A_Viruses/7.02%3A_The_Viral_Life_Cycle
dKBiB62mCv2XuFr-	New physical geography, by Ralph S. Tarr.	AT CORNELL UNIVERSITY AUTHOR OF "ECONOMIC GEOLOGY OF THE UNITED STATES," "ELEMENTARY GEOLOGY," "physical GEOGRAPHY OF NEW YOilK, fT!\.TE," ETC, AND CO-AUTHOR OF " TARR-MCMURRY GEOdDA^VHiES'" . .' By the MACMILLAN COMPANY. Set up and electrotyped. Published January, 1904. Reprinted, May, 1904; January, August, October, 1905; • ■ ,'. April* jls^c^embe^, 1906; September, 1907; January, Octo- '; %'' lie'r','' iJo^V 'jWary, 1909; January, July, 1910; April, August, 1911;^FQbwary, 1912; September, 1912; March, . ', 'I '.[I'Mi'i^l 5913' Jamuary, April, 1914; March, 1915; August, ,1 .' J/r •W15;'P\brna^y,« Jify, November, 1917. PREFACE. Nearly eight years ago the author published his Elementary Physical Geography, which was followed, two years later, by his First Book of Physical Geography, really a presentation, in briefer and more elementary form, of the matter contained in the earlier book. The growth of the science of physical geography, — which has been little short of marvelous, — the rapid advance in rank which the subject has won for itself in the schools, and the new ideas and new methods of presentation which have come to the author, have, for several years, made him desirous of undertaking a revision of one or both of his texts. When, however, this desire was given concrete form, and systematic attention was paid to the nature of the revision, it became evident that it would mean, not merely a revision, not even a mere rewriting, but a complete destruction of the old book and the construction of an entirely new book, different in plan, in scope, and, in many respects, in subject-matter. Then, for the first time, arose the idea that, since it would be a new book in fact, it would be better to issue it as such than as a new book under an old title. One important reason for reaching this decision was the fact that both the Elementary and First Book are in wide use. A field for them evidently exists, and it appears hardly wise to destroy absolutely that for which there is a demand. Twelve editions of the Elementary have been published and fifteen of the First Book. mental stage, and it is the opinion of many teachers that the ideal method of presentation has not yet been proposed, notwithstanding the several excelibnt texts which have appeared. The New Physical Geography is still another effort to solve the problem of how best to present the subject to beginning students. The author does not flatter himself that he has produced the ideal ; his only hope is that he has done better in his third attempt than he did in the other two. In the New Physical Geography, treatment of the lands has been placed before that of air and ocean because so many schools commence the study in the fall and take classes into the field. The chapters on atmosphere and ocean have been given less space than in the author's previous books ; yet all topics of distinct importance are treated with sufficient fullness to make them clear. Certain subjects that are not universally deemed necessary parts of physical geography are treated in appendixes ; it is the belief of the author that each of these should be studied. Perhaps the most decided difference between the New Physical Geography and the author's other books lies irr. the introduction of a much fuller treatment of life in its relation to the land, air, and ocean, the human interest ol each topic being emphasized. This has been done throughout the text and, at the end of the book, in a series of chapters devoted to that subject exclusively. Especial pains has been taken to illustrate the book fully. It is believed that an illustration, properly selected, is of the very highest value, — the best substitute for the object itself. Every illustration in the book is introduced for use, and almost every one is referred to at least once in the text. Among these illustrations half tones of photographs predominate, for they alone, of all forms of illustration commonly in 1 BE FACE. vii use, present the whole truth. In order that they shall be distinct, the half tones are all printed on glossed paper ; but to avoid giving the book undue weight, and to eliminate the trying effect of glossed paper on the eye, the text is printed on a light-weight, dull-finished paper and the half tones on inserted sheets. Besides half tones there are many diagrams, maps, and block drawings, the latter prepared by C. W. Furlong of Cornell University. As aids to the study of the text, a brief Summary is given at the close of each section, and a Topical Outline and a set of Review Questions are placed at the end of each chapter. It is believed that the great majority of teachers will welcome these aids. No teacher will, of course, be content to follow the questions absolutely and without modification ; the individuality of the teacher will appear here, as elsewhere. But these summaries, topics, and questions cover the essentials in the text ; and their use as a basis for work, with such modifications and additions as may be deemed necessary, will be a far lighter task than the production of an entire series by the teacher. Thus, relieved of a form of drudgery, time will be available for the expenditure of energy in more profitable lines. In most of the better schools physical geography is fast becoming a laboratory science, and this is the position it must eventually take wherever taught. In the absence of a laboratory manual, many teachers find it difficult to plan a laboratory course. That this is so is evident from the many letters that the author receives on the subject. With this in mind, a series of Suggestions is appended to nearly every chapter, and one appendix is devoted to maps and laboratory equipment, another to field work. From these suggestions any teacher will be able to select some for use. It ir hoped that they may serve as an incentive to additionaJ laboratorv and field work. A very large number of teachers have given the author the beneht of their experience in the form of suggestive criticism. To all of these teachers — making a list far too long to print here — the author is greatly indebted for their kindly interest. They have helped to shape the plan of the book. Among these, however, are several whose suggestions were of such marked value that their aid must be acknowledged individually : Frank Darling, Chicago Normal School ; C. S. Jewell, Lake View High School, Chicago; E. C. Case, Milwaukee Normal School ; L. O. Towne, Haverhill, Mass. ; Emerson Rice, Hyde Park, Mass. ; H. L. Rand, Dedham, Mass. ; H. L. F. Morse, Troy, N.Y. ; Miss Agnes Brown, Rockford, 111. ; and James A. Barr, Stockton, Cal. Special acknowledgment must also be made to Lawrence Martin of Cornell for valuable assistance and suggestion during the preparation of the book. It goes without saying that the author is profoundly indebted to the host of workers in physiography, from whom he has drawn so much inspiration, suggestion, and fact : Gilbert, Davis, Powell, Geikie, Penck, de Lapparent, Russell, Shaler, Dutton, Chamberlin, Hayes, Campbell, Salisbury, Brigham, Dodge, Dryer, and many others. From the writings of these physiographers the author has culled whatever seemed to him suited to a scheme of elementary instruction ; and so numerous, and often so unconscious, is the influence of these fellow-workers, that 8[)ecific acknowledgment would be quite impossible. Doublless the most profound influence upon the author is that of liis two teachers. Professors Shaler and Davis, tlie importance of which to him cannot be overestimated. Together with other physiographers, the author further recognizes in Professor Davis a leader in American physiography, from whom even some of the fundamental principles of the subject have been derived. An examination of the following pages would show the influence of this physiographer in many places, an influence not confined to the pure science, but extending to the pedagogy of ACKNOWLEDGMENT OF ILLUSTRATIONS. Aside from the illustrations acknowledged in the list below, and a few acknowledged beneath the pictures themselves,, a number of photographs were obtained from a great variety of sources, American and foreign. Many of the photographs were taken by the author ; many are from the collection in the department of Physical Geography at Cornell University. For photographs, especial acknowledgment is due Mr. J. 0. Martin, formerly of Cornell University ; William H. Rau, Philadelphia ; F. J. Haynes, St. Paul ; Detroit Photographic Co., Detroit ; and S. R, Stoddard, Glens Falls, N.Y. The topographic maps are made from the United States Geological Survey topographic sheets ; the weather maps and many of the diagrams of temperature, etc., are based upon maps and data obtained from United States Weather Bureau Publications. Most of the relief maps are reproduced from models made by E, E. Howell, Washington ; many of the drawings, especially the block drawings, are by C. W. Furlong, of Cornell University. The animal pictures and the map and picture of the races of man are by MatthewsNorthrup Co., Buffalo. A number of illustrations were taken from earlier books by the author. Of the remaining illustrations a few are made from copy whose source could not be ascertained. Illustrations taken from books, or based upon maps or diagrams in books, and a few photographs not purchased from dealers, are acknowledged in the following list : — Agassiz, A. (Three Cruises of the Blake), 324, 325, 343. Bartholomew (Physical Atlas, Meteorology), 407, 435. Von Bebber (Lehrbuch der Meteorologie) , 425. California State Mineralogist's Report, 238. Calvin, Prof. S., Des Moines, la., 88. Canadian Geological Survey, 46. Carney, F., Ithaca, N.Y., 282. 454, 456. Fairchild, H. L. (New York Geological Survey), 273. Foerste, A. F. (Proceedings Boston Society Natural History), 1G8. Friez, J. P. (Dealer in Meteorological Instruments), Baltimore, Md., 561, (Lake Bonneville), United States Geological Survey, 301. Harden, E. B. (Pennsylvania Model), 172. Harvard College Observatory, 2, 5. Hayden, E. (National Geographic Magazine), 426. Hayden, F. V. (Geological Survey Territories), 138, 140, 159. Heim, A. (Mechanismus der Gebirgebildung) , 156. Hill, K. T. (Topographical Atlas, Texas), United States Geological Survey, 96, 144. Holden, E. S. (Memoirs National Academy of Sciences), 382. Hovey, E. 0. (American Museum Natural History), New York, 197, 198. Ikenberry, W. L., Mt. Morris, 111., 420, 422. Johnston-Lavis, H. J., 195. Jones, Thomas (Earth Model), Chicago, 111., 313. Jukes-Browne, A. J. (Handbook of Physical Geology), 344. Kent, H. Saville- (Great Barrier Reef), 380. Koppen (Atlantischen Ozean), 409, 410. Libbey, Prof. W., Jr., 266, 272, 486, 524. McAllister, T. H. (Dealer in lantern slides). New York, 484, 490, 496. Mexican Boundary Commission, Report, 147. Mills, F. S., Andover, Mass., 92. Milne and Burton (Great Earthquake of 1891 in Japan), 239. Nasmyth and Carpenter (The Moon), 14. Newberry, J. S. (Popular Science Monthly), 462. Penrose, R. A. F., Jr., Philadelphia, 126. Powell, J. W. (Explorations of the Colorado River), 36, 59, 139, 478. Ratzel, F. (History of Mankind), 489, 491, 493, 529, 534, 538, 546. Ried, Prof. H. F., Baltimore, Md., 250. Ritchie, J., Jr., Boston, 171, 284. Russell, Prof. I. C, Ann Arbor, Mich., 252, 256, 257, 258. Shaler, Prof. N. S. (United States Geological Survey), 90, 305. Shedd, S. (Washington Model), 476. Sigsbee (Deep-sea Sounding, United States Coast Survey), 310, 312. United States Hydrographic Bureau, 427. United States Weather Bureau (Monthly Weather Review), 402. Upham, W. (Lake Agassiz), United States Geological Survey, 130. Ward, R. de C, Series of Cloud Slides, 402, 423. Webster, Commander H., United States Navy, 543. Willis, B., United States Geological Survey, 39, 40, '48. Williston, Prof. S. W., Lawrence, Kan., 64, 127. INTRODUCTORY. Man is vitally dependent upon air, water, and earth. The air supplies oxygen for breathing and for fire; it supplies carbon dioxide to plants; it brings vapor for rain; and its presence and movements profoundly affect climate. The ocean is the source of vapor; it furnishes many kinds of food fish; it is the highway of an ever increasing commerce; and it influences the climate of every land. The lands furnish a home for man; they are mantled with a soil in which the food plants grow; and from the rocks are obtained mineral fuels, building stones, and metals. Both plant and animal life are greatly influenced by the forms of the land and the distribution of land and water. The sun is also of vital importance, for its heat and light make life on the globe possible. The heat sets the air in motion, forming winds which bring rain, modify climates, and start waves and currents in the ocean. The movements of the earth — rotation and revolution — are also important. .Rotation brings day and night, which influence the habits of men, animals, and plants. Revolution causes seasons, which have a still greater effect on life. Plants, animals, and mankind have adapted themselves in a wonderful manner to the soil, climate, and other features of their surroundings. Most animals and plants live either in the water or on the land; but some have adopted the air as their home, while others have taken to life underground, though always near the surface. Air and water are ever changing; the lands are also changing, though more slowly; and plants and animals are varying in their relation to air, ocean, and land. These changes have a profound effect on man, and it is therefore important to study about them. ' THE EARTH AS A PLANET. The earth is not an exact sphere, for the diameter at the equator is 7926%niles, and at the poles 7899. This difference in the two diameters is due to a slight flattening at the poles. Such a slightly flattened sphere is called an oblate spheroid. Compared to the earth as a whole this flattening is so slight that it cannot be shown on an ordinary globe. « Summary. — The earth is a slightly flattened sphere, or oblate spheroid. Its curved surface can be seen on the ocean ; eclipses of the moon prove that it is a sphere ; its size and shape have been measured ; and the distance around it in all directions is known that distance, making life on the earth possible. The sun is the center of a family of spheres which form the solar system. In this system there are eight large spheres called planets, of which the earth is one. The sun and stars shine by their own light ; but the planets merely reflect sunlight, as the moon does. The bright evening and Fig. 7. — To show the great size of the sun. The earth, moon, and orbit of the moon could all be placed inside the sun, as shown. Some of the planets are far more distant than the sun (Fig. 8), Neptune, the most distant of all, being over 2,700,000,000 miles. How distant that is may perhaps be understood by the following illustration. If an express train could have started toward Neptune in the time of Christ, and have traveled steadily onward day and night at the rate of sixty miles an hour, it would not yet be halfway there. Not only are the planets far away, but some of them are very large (Figs. 9, 10). Jupiter, the largest, is 86,000 miles in diameter. In the space between Mars and Jupiter there are also a number of very small spheres, called asteroids. The largest is about 500 miles in diameter. Summary. — Other spheres besides the earth are the stars, sun, moon, planets, and asteroids. TJie moon and p?awe^s are cold, and shine by reflected light ; the stars and sun are fiery hot. In the solar system, 7thich includes the S2in, moon, j^lanets, and asteroids, the largest sphere is the sun, the largest planet Jupiter, and the most distant planet Neptune. sun. This revolution^ is along a nearly circular path, or orhit. The orbit is not an exact circle, but an ellipse (Fig. 11), and the sun, instead of being at the center, is a little to one side, at one of t\\Q foci of the ellipse. This causes 6 NEIV PHYSICAL GEOGRAPHY. Mercury, the smallest and nearest of the planets (Figs. 8, 9), requires only 88 days for a single revolution. What is the time required by the other planets (Fig. 12) ? Summary. — So far as known, all the planets rotate 07i axes, and all revolve aromid the sun in elliiitical orbits. The jjeriods of rotation and revolution differ. Satellites accompany several of the planets. 4. Rotation of the Earth. — Many uninformed people believe that the sun rises, passes through the heavens, and sets in the west. Our own ancestors, centuries ago, held the same belief. We still use their terms, sunrise and sunset., though we well know that it is the turning of the earth on its axis that makes the sun appear to rise and set. In looking from the window of a train it sometimes seems as if objects were passing by, while it is really you yourself that is moving. In the same way, as the earth turns with us toward the east, the sun seems to travel in the opposite direction. seem to circle round it. 5. Effects of Revolution and Rotation. — Rotation of the earth has given the basis for our computation of time. Thus we reckon a day as the period required for one rotation (24 hours). The day is divided into hours, each hour being the time required for the sun's rays to advance 15^ over the curved surface of the rotating earth. By rotation, also, the day is divided into a period of light and one of darkness. Name some habits of plants, animals, and men that are determined by this effect of rotation. Revolution of the earth is also a matter of the highest importance. By it another standard of time, the year, is fixed. Revolution also causes an apparent movement of the sun, by which it rises and sets farther north or south at different times. These changes in the sun's position. which cause the seasons, have determined some of man's most characteristic habits. Name some ways in which revolution affects you, — your home, clothes, foods, and games. Recall from your study of geography how revolution affects the habits of the Eskimos. Summary. — Rotation determines the length of our day, causes day and night, and influences our habits. Revolution gives us our year, our seasons, and also profoundly affects our habits. 6. Gravity and Gravitation. — The earth exerts on all bodies upon it an attraction which we call gravity. By gravity men are held to the surface of the earth ; a stone thrown into the air is drawn back to the earth; the air is prevented from flying away into space; and the oceans are held in place. It gives to the ocean a curved surface, because each particle of water is attracted toward the center of the sphere. Each part of this curved surface, or sea levels is at right angles to a line leading toward the earth's '' ^nter. Bodies in space also exert an attraction on other spheres. For example, the moon exerts an attraction upon the earth, and the earth upon the moon; but the earth, being larger, has the stronger effect. This attraction of bodies in space is called the attraction of gravitation. Gravitation is the bond that holds the earth and other planets to the orbits along which they travel about the sun. If it could be possible for the sun to lose its attraction of gravitation, the earth would fly off into space, as a stone whirled by a string flies away if the string breaks. Gravitation also holds the moon so firmly that it swings around the earth with such regularity that its position a thousand years from now can be accurately foretold. The law of gravitation was discovered over two centuries ago by Sir Isaac Newton; yet even now no one knows exactly what causes it nor why it operates in the universe. held by gravitation, the earth is able to travel along its orbit of 600,000,000 miles each year at a rate of over 1000 miles a minute. At the same time, it is whirling on its axis so rapidly that a person on the equator is moving at the rate of 17 miles a minute. We are not aware of these rapid movements, because the land, water, and air go with us. Even when traveling on a noisy railw^ay train, we sometimes forget that we are moving. But the earth moves without jar or noise, and there are no near-by objects for us to swiftly pass ; these rays cross the 93,000,000 miles that separate us from the smi. They reach the earth in about 8 minutes, while^ at the rate of a fast express train, 175 years would be required. The distant planet Neptune doubtless receives too little heat for life ; Mercury is so near that it perhaps receives too much ; but the earth is so favorably situated that it receives neither too much nor too little. As the sun cools down to a red heat, in some far-distant future age, life on the earth will no longer be possible. Summary. — TJie members of the solar system shotv signs of heat, either past or present. Heat, radiated from the ivhite hot sun, passes rapidly across space ; ayid some of it, reaching the earth, makes life possible. 5. Effects of Rotation and Revolut on. — (.r) Rotation : effect on divisions of time; on day and night; m L ibits of man, (h) Revolution: effect on division of time ; on seasons: on habits of man. 6. Gravity and Gravitation. — (a> ^Sravity : nature; effects; nature of sea level, (b) Gravitation : nature : movements of moon and planets ; discovery by Newton, (c) RaDid movements of earth. 7. Heat in the Solar System, —(a) Evidence of heat in the solar system, (b) Sun's heat: condition of sun; rate of passage of rays; proportion received by earth ; other planets ; effect of future cooling of sun. Questions. — Section 1 What was formerly believed concerning the shape of the earth? What proof is there that the earth is spherical? What is its exact shape ? Give its two diameters. 2. What other kinds of spheres are there ? How do planets and stars differ? What is the solar system ? What are asteroids ? Give the distance from the sun to each of the planets (Fig. 8). Name the planets in the order of their size (Figs. 9 and 10). 3. What important movements have the planets ? State the difference in time of rotation. Of revolution. What is the distance from earth to sun at opposite seasons? Why this difference ? Give some facts about satellites. 4. AVhat was formerly thought regarding the daily rr.ovement of the sun ? What is now^ known to be the cause of it ? Describe the movement of the stars, and explain them. 6. W^hat is gravity ? Give examples of its effects. W^hat is the attraction of gravitation ? What effect has this upon revolution? Why are the earth's movements not more noticeable 7. What is the evidence of heat in the memib<^rs of the solar system? What change is going on in the sun? Whflu effect has that on the earth? Why is there probably no life on N.i^oune or Mercury? At vhat rate does sunligQt travel ? Suggestions- — ■ These sugges/ions are mad6 rather freely, though it is not expected that any school iv ill find it feasible to-^f-rry out all, or even a majority. From among them, however, every teacher tviU find it possible to select some. (1) Carefully examine the moon and n^rfce its roundness. If possible, look for the craters through ^, telescope or spyglass. (2) If an eclipse of the moon comes during thp year, observe it and note the circular outline of the earth's shadow. (3) With a lamp, throw on the wall the shadow of a ball in various positions. Do the same with a cylinder ; with a square. Which always shows one kind of outline ? (4) A period devoted to the meaning of scale may be combined with a study of the size and distance of the members of the solar system. This can be done with profit by cutting disks out of brown paper to represent the planets (say on a scale of one inch for 5000 miles) ; and marking off distances in the school yard (say on a scale of one inch for 200,000 miles) to represent distances. (5) Take a string five feet long with a loop in the end. Put the loop over a nail driven in the floor. With a piece of chalk at the other end of the string draw a circle. Now drive another nail two inches from the first. Take a string ten feet long and tie the ends. Put it over the two nails, and with chalk held in the loop draw a figure as near a circle as you can. It will not be a circle, but an ellipse. If you put the two nails (the foci) farther apart, say six inches, the ellipse will be still less like a circle. (6) Rotate a globe or apple in front of a light to understand the cause of day and night. (7) Observe the stars of the Great Dipper and the North Star at 8, 9, and 10 o'clock. What changes do you notice ? (8) Compare the movements of a planet in the heavens, say the evening " star," with that of a neighboring star. Why the difference ? (9) With a telescope look for the moons of Jupiter and the rings of Saturn. (10) What are shooting stars and comets? (11) In some astronomy, read about the sun and the planets. (12) Find out what Aristotle, Magellan, and Galileo learned about the earth. Reference Books. — References to a few selected hooks are placed at the end of each chapter. Other reference hooks and magazines are listed m Appendix L. Newcomb, Elements of Astronomy^ American Book Co., New York, 1900, ^1.00 ; Young, Manual of Astronomy, Ginn & Co., Boston, 1902, $2.45; Todd, New Astronomy, American Book Co., New York, 1897,^1.30; Lockyer, The Chemistry of the Su7i, Macmillan Co., New York, 1887, ^4.50. and nitrogen, whose presence on every hand we hardly realevery breath draws it in for the puring life-giving oxygen. Though it we feel its presence when the wind moving rapidly through it. causes fire to burn, and, by a slow combustion, causes decay of animal and plant tissues. It diffuses light and heat from the sun, and transmits the sound waves upon which hearing depends. Winds, which bear vapor and warm and cold air from place to place, are a result of its movement. For many centuries the wind has been used for driving ships through the water and for turning windmills on the land. The surface of the earth itself is profoundly modified by the influence of the air. Winds move loose fragments about and wear the rocks away, especially in desert regions. Eains, made possible by vapor in the air, give rise to streams, which carve channels in the land and bear rock fragments to the sea. Waves, which winds form in the ocean, batter at the rocky seacoast. Even quiet air, by the action of its water vapor and oxygen, is causing the solid rock to slowly decay and crumble. This forms the soil upon which so many plants depend for food. Summary. — Hie air, composed chiefly of oxygen and nitrogen, extends 200 or 300 miles above the earth, hut Is mainly near the surface. Breathing, fire, decay, diffusion of light and heat, hearing, winds, rain, toaves, and many changes of the land, includijig the formation of soil, are dependent on the atmosphere. 9. The Oceans.^ — If the earth were a perfect sphere, it would be entirely covered by water to a depth of several thousand feet ; but the surface is so irregular that the ocean is not able to completely cover it, as the air does. It has been drawn by gravity into the depressions and rises high enough to cover only the continent margins (Fig. 316). Nearly three fourths of the solid earth is hidden from view by this water mantle, the area of the oceans being about 145,000,000 square miles, of the lands about 52,000,000 square miles. Near their contact with the continents the oceans are shallow ; but far from land the wa^er is deep. One may sail, with no land in sight, for thousaridf^ of miles in water whose average depth is 10,000 to 15,000 Toet. In half miles. This vast expanse of water is of great importance in many ways. It is the seat of abundant life, many forms of which are of such value that ships are sent out to secure them. Cod, halibut, haddock, bluefish, salmon, shad, lobsters, oysters, clams, seals, whales, sponges, pearl oysters, and precious corals are among the ocean animals of importance to man. For a long time the ocean was an almost impassable barrier to the spread of man ; but as men learned to navigate and to build strong ships, it became a highway instead of a barrier. To-day the Atlantic is crossed with speed and comfort in iive or six days ; less than a century ago this journey required weeks and was one of peril. To-day communication between America and Europe is easier than between Rome and Athens at the time of the Roman Empire. Ships now cross the oceans in all directions, carrying merchandise and passengers to every quarter of the globe. The harbors from which these ships go forth have become the seats of great cities, prospering by their commerce a,nd by the industries to which it gives rise. By means of the ocean highway, too, civilization has rapidly spread to all quarters of the globe. It is the ocean that supplies the vapor for rain, upon which all land animals and plants depend. The ocean also profoundly influences the temperature of neighboring lands, moderating the heat of summer and the cold of winter. Therefore, lands reached by ocean winds, like the northwestern coast of United States and Europe, have far less extreme climates than lands in the same latitude, like central and eastern United States, where ocean winds are less common. Summary. — TJie ocean occupies depressions on the eartWs surface, covering three fourths of the globe to an average depth of 10,000 to 15,000 feet. The ocean is of importaiice as a source of food-fishes and other valuable animals; as the seat of extensive navigation; as the source of vaj^or; and in modifying climate. 10. The Solid Earth. — Near the continents the sea floor is covered with sediment washed from the land by rain, rivers, and waves. Farther out, it is mantled with the remains of animals that, on dying, have settled from the water above. Almost everywhere on the dry land there is a layer of loose rock fragments, the surface part of which is called soil. Thus nearly the entire earth is covered by loose materials. In some places the soil has been brought by glaciers, in others by rivers; but most of it has been formed by the decay and crumbling of the rocks. Were it not for this soil Wherever the soil mantle is penetrated to great enough depth, solid rock is found beneath it (Fig. 17). Sometimes the rock is several hundred feet beneath the surface; but it is usually found at a depth of a few feet or a score or two of feet. In places, especially among mountains or on other steep slopes, there is no soil-cover at all. As the rock decays in such situations, the fragments fall away so quickly that soil cannot accumulate. The rock that is everywhere found beneath the soil varies greatly from place to place, often consisting of materials which are of great use to man. In some places it is sand- stone or granite, useful for building purposes ; in other places it is limestone, valuable for building, for making lime, or for use in blast furnaces. In various parts of the world, layers of coal are found bedded with the of iron ore, salt, and other substances ; also veins of lead, zinc, silver, gold, and other metals. Summary. — The solid earth, like the air and ocean, is of great importance to man. It furnishes him ivith a home ; it is almost everywhere covered ivith a soil mantle, in ivhich food and other plants grow ; everywhere beneath the soil mantle is found solid rock, from which many valuable mineral substances are obtained. perhaps made of metal. Several facts indicate that the interior is highly heated : there are hot springs ; volcanoes erupt melted rock ; and mines show an increase in temperature of 1° for every 50 ing point of rocks must be reached at no great depth. It was formerly believed that beneath a thin outer crust the interior was molten ; but it is now considered certain that, though very hoi, the interior is solid. We still use the term earth's crust, however, for the cold outer portion of the earth. There are a number of reasons for the belief that the interior is solid : (1) if it were liquid there would be tides in it ; (2) the behavior of the earth toward other spheres is that of a solid body ; (3) earthquake shocks in Japan have been measured by delicate instruments in England, and the time of passage indicates a solid interior. It is a well-known fact that greater heat is required to melt most substances under pressure than without pressure. It is believed, therefore, that the interior of the earth is prevented from melting by the tremendous weight, or pressure, of the rocks that rest upon it. At a depth of six miles the pressure is great enough to crush rocks ; and, therefore, deep in the earth, below this upper portion, or zone of fracture, cavities cannot exist. The interior heat is one of the arguments in favor of the belief that the earth was once a still hotter body (p. 9), probably part of a nebula, from which the sun, earth, moon, and the other members of the solar system have descended. The earth is still losing heat; but it is so large that many ages more will be required to make it completely cold, like the smaller moon. Summary. — Several facts indicate that the interior of the earth is highly heated, and it ivas formerly thought to he molten ; hut, for a number of reasons, it is now believed to he solid, though hot, being prevented from melting by the pressure upon it. 12. Air, Water, and Rock. — At ordinary temperatures the air is a mixture of gases ; but with great cold and pressure these gases may be changed to a liquid and even to a solid state. Water, ordinarily a liquid, changes at 32° to a solid- GENERAL FEATURES OF THE EARTH. 19 and at 212° to a gas; in fact, some water- vapor gas rises from water at ordinary temperatures. Rock, as we know it, is a solid; but volcanoes show that under higher temperatures it becomes a liquid; and in the very hot sun, some of the rock elements are so hot that they are in the state of gases. From this it is seen that the terms gas^ liquid^ and solid apply merely to states of matter. When the conditions change, any one of these states of matter may be altered to one of the other states. The three earth materials — air, water, and rock — have been spoken of as if they were quite separate ; but really they are closely related and mingled. There is not much rock material in the atmosphere, though volcanic dust is often borne long distances in it ; and the haziness of the air is partly due to dust blown up from the ground. Water vapor is mixed with all air, even that of the driest deserts. Water also pervades the earth's crust, entering even the densest rocks. Wells reach it and supply drinking water ; it slowly oozes from the ground in springs ; miuers find it far below the surface ; and volcanic eruptions bring vast quantities of it to the surface. In cold climates it is frozen, changing the soil to a solid, rocklike mass. In northern Siberia the ground is permanently frozen to a depth of several hundred feet. That air also enters the ground is proved by the fact that many plants die for lack of it when their roots are submerged. grled in suspension are also present in water. Summary. — Air (gas), ruater (liquid), and rock (solid) may each oe changed to one of the other states of matter. Tliey are mingled: there is earth material and water vapor in the air ; air and water in the earth; and air and rock material in the water. ocean basins between different levels. regular. Its surface is roughened by a series of continent elevations, between which are broad depressions, occupied by the oceans. The ocean depressions average 10,000 to 15,000 feet in depth; but the average height of the lands above sea level is only 2000 to 3000 feet. Fully three fourths of the above the general level of both sea bottom and land. The Hawaiian Islands are volcanic cones on a submarine mountain fold fully 1500 miles in length ; and the Japanese Islands, Philippines, and West Indies are also mountain chains rising from the sea floor. It is among the mountain chains of the land that the greatest elevations on the globe are found. In the Andes there are peaks that are over 40,000 feet above the sea bottom 75 miles to the west. The highest mountain in the world. Mount Everest, is about 5^ miles high ; and the greatest ocean depth is about the same distance beneath the sea. Eleven miles is a great height as we look at it ; but it is a very small amount compared to 7900 miles, the diameter of the earth. These irregularities of the earth's surface are generally believed to result from the heated condition of the interior (p. 9). As the earth cools and shrinks, its crust wrinkles, causing some parts to rise, others to settle (p. 35^. Such changes of level are even now in progress (p. 36), and there are many proofs that they have caused great change in the past. One of the most important facts in physical geography is that the earth's the lands and oceans are ever varying. Summary. — Tlie earth's surface has been roughened by the effects of shrinking of the heated interior. This has caused continent elevations and ocean depressions, and, on both of these, mountain chains and volcanoes. The average depth of the ocean is about five times the average height of the land ; but the loftiest mountains are about as high as the greatest ocean depths j making a total difference in level of about eleven miles. 14. Conflict of Erosion and Elevation. — Wherever land is exposed to the air, it is being attacked and slowly worn away. The weather causes the rocks to slowly crumble (p. 38); rivers carve valleys and carry the rock fragments off toward the sea (p. 52); glaciers scour the land over which they pass (p. 153) ; waves batter the shore, cutting cliffs, building beaches, and supplying rock fragments for removal by the currents (p. 210). The result of the work of these agencies of erosion is that the land surface is made very irregular. The sea floor, on the other hand, is made more regular. Beyond the reach of the waves there is practically no erosion ; but the deposit of rock fragments from the land is leveling the sea bottom. Thus, on the one hand, movements of the crust are raising the land; on the other, the agencies of erosion are cutting into it and removing its fragments toward the sea. There is an opposition, or conflict, of two sets of forces, one set tending to raise, the other to lower the surface of the land. So far the forces of elevation have been more powerful ; but the agencies of erosion have deeply sculptured the lands and have helped to level the sea floor. This conflict has been in progress for many ages, and the present land surface, about which we are to study, is the result of it. The valleys, which our railways and canals follow ; the mountains, which act as barriers to winds and to the spread of plants, animals, and men; the smooth coastal plains ; the interior plateaus ; the harbors in which our shipping gathers ; the sites of our leading cities ; and many other land features are a result of the conflict between the forces of elevation and the agencies of erosion. Summary. — Agencies of erosion — weather, rivers, glaciers, ivaveSj etc. — are cutting irito the land and strewing the icaste over the sea floor. On the other hand, forces of elevation are raising the land. This causes a conflict, in which the forces of elevation have so far been more j^otent. The present land surface, which so greatly influences man, is the result of this conflict. 15. The Continents — (A) Oharacteristics. — A continent is a large upraised portion of the earth's crust nearly or quite surrounded by ocean. Usually the continent margin is submerged beneath the sea (Fig. 316), sometimes, as off eastern North America, for a distance of 50 to 100 miles from the coast. At its outer edge it is faced by a steep slope, called the continental slope (Fig. 116), which descends quickly to the deep sea bottom, Althougii the average elevation of the continents is but 2000 to 3000 feet above sea level, when measured from the base of the continental slope their average height is 10,000 to 15,000 feet. Some portions, for example the Dead Sea, are below sea level. Continents consist of mountain ranges with connecting plains and plateaus (Figs, 20, 21). They are crossed by rivers, occupying valleys, which drain the land ; but nearly one fourth of the land has no drainage to the sea. In these cases the water runs into interior basins or basins without outlet. The outline of a continent seems to be determined by its mountain ranges ; indeed, mountains have been called the skeletons of continents. From this standpoint the plains and plateaus may be called its tissues. In fact, the plains and plateaus have been built of rock fragments worn from the mountain skeleton. To illustrate, off eastern Asia, from the Kurile Islands to the Philippines (Fig. 26), there is a mountain cliain now rising. A large part", of the rock waste worn from these mouufcains, and from the mainland, is being deposited in the sea that separates the islands from the mainland. These deposits may in time fill the inclosed sea, and a slight uplift of the land may raise the smooth sea bottom plain, forming dry land, and thus joining the mountain islands to the coast of the mainland. It is by similar changes that continents have been made. Summary. — Continents are uplifted blocks of eartWs crust ivhose real margin is beneath sea level. They consist of plains, plateaus, and mountains, partly drained into interior basins. They oive their outline to mountain skeletons, connected by plains and plateaus^ that have been built of rock fragments luorn from the mountains. (B) North America. — In North America (Fig. 22) there are two great systems of mountains : (1) the Appalachian system, which extends south westward from Labrador to Alabama ; and (2) the great western system, or the western Cordilleras^ Avhich extends southeastward from Alaska to Central America (Fig. 20). A third system of low and very ancient mountains occupies the region from Labrador westward. The vast plateaus and plains that connect these mountains are largely made of rock fragments swept from the mountains in past ages. Fossil remains of marine animals prove that the rock strata were deposited in a sea, and were later raised by the forces of elevation to form dry land. Its triangular mountain skeleton has given to North America its form. The continent is broad in the north and tapering in the south, because the mountains are spread farther apart in the north. Mountains have also caused some of the larger irregularities of the continent. For example, the Alaska and Labrador peninsulas are the northern extension of the western and eastern mountains (Fig. 22). Lower California is a southern extension of the Coast Ranges ; and the Gulf of California is a depression not yet filled with the waste that is being washed from the bounding mountains. The peninsulas and islands which partly inclose the Gulf of Mexico and Caribbean Sea are also portions of mountain systems. Sinking of the land, which allows the sea to enter the valleys, is another cause for irregularities in the outline of a continent. Such a sinking in northeastern America has submerged land valleys, forming Hudson Bay, the Bay of St. Lawrence, the Bay of Fundy, Long Island Sound, New York Harbor, Delaware Bay, Chesapeake Bay, and many thousands of smaller bays, estuaries, and harbors. Where the sea has risen so as to completely surround areas of higher land, islands have been formed, such as Long Island, Newfoundland, and the thousands of others along the northeastern ;j»nd northwestern coasts of America. Summary. — North America owes its triangular shape to its mountain areas, spread apart in the north. The connecting plains and plateaus are made of rock waste derived from these mountain skeletons. The principal irregularities — peninsulas, hays, and islands ' — are due to two causes: (1) mountains; (2) sinking of the land. (C) South America. — South America resembles North America in its triangular form (Fig. 23). This outline is due to the great mountain backbone of the Andes in the west, and the less prominent mountain systems in the north and in eastern Brazil. South America is, however, far more regular than North America. The only irregularities caused by mountains are in the north, where the Andes system forms the Isthmus of Panama and the small peninsulas of Venezuela. The irregular southern coast is due to sinking of the land; but the coast of Peru and northern Chile is now rising (p. 36). Summary. — The mountains of South America have given it a triangular form a7id one or two peninsulas in the north; elsewhere the coast is very regular, excepting in the south, where there has been sinking. (D) Africa. — Like South America, Africa has a triangular form and regular outline (Fig. 24). Its outline is determined by mountain uplifts near the coast, which have so raised the interior that it is mainly a broad plateau. Only one eighth of the continent lies below an elevation of 600 feet. MadagS-scar is part of a mountain chain ; the peninsula of Tunis is the eastern extension of the Atlas Mountains; and the peninsula of Abyssinia is also due to mountain uplift. There are few harbors, because there has been no extensive sinking of the land. mountains near the coast. Its coast line is remarkably regular. (E) Australia. — The continent of Australia (Fig. 25) is a huge island. A mountain chain in the east, and others in the west, have helped determine its form ; but the mountains are not so arranged as to develop a typical triangular shape. York peninsula in the northeast, and the peninsula of Victoria and the island of Tasmania in the southeast, are continuations of the eastern Australia mountains. A sinking of this continent has caused many small bays and excellent harbors. S07newhat irregidar coast. (F) Eurasia. — While the other continents stand out quite by themselves, Europe (Fig. 27) and Asia are so closely connected that they are often considered as one continent. Had the study of geography not started in Europe, it is probable that it would have been called a part of the immense continent of Eurasia (Fig. 26). This great land area has an irregular triangular form, one angle of the triangle being at Bering Strait, the second in Indo-China, and the third, in Spain. Eurasia is so mountainous a land, with mountains extending in so many directions, that its coast line is exceedingly irregular. Its great peninsulas - — Kamchatka, Korea, IndoChina, India, Arabia, Greece, Italy, Spain, and Scandinavia — are all due to the presence of mountains. The numerou large islands, including the Philippines, the East Indies Japan, Sicily, Corsica, Sardinia, and the British Isles, arv also parts of mountains. Between these mountain uplifts are inclosed many bays, seas, and gulfs. Parts of this land, especially northwestern Europe, have been lowered beneath the sea. This sinking has formed the fiords of Norway, the Baltic, North, and Irish seas, and a multitude of estuaries, small bays, and harbors. It has also separated the British Isles from the mainland. Summary. — Europe is a part of the great Eurasian continent, which has a rough triangular form. The many p)eninsulas, bays, islands, etc., are due to mountain u2)Ufts and to sinking of the land. (G) Influence of Continent Eorms on Man. — The separation of the continents has interfered with the spread of man. Their low elevation has been very favorable to mankind. Had the average elevation (2000 to 3000 feet) been as great as the average depression of the oceans (12,000 to 15,000 feet), the greater part of each continent would be too high and cold to support a dense population. The development of men and nations has been influenced in many ways by the continent form, the outline of its coast, the inclosed bays and seas, the islands, and the distribution of mountains and plains. An irregular coast line favors navigation ; and it is an interesting fact that the inhabitants of continents that have regular outlines have advanced far less rapidly than those whose coast has many harbors and bays. Illustrations of these influences and others, on man, animals, and plants, will appear in later chapters. tineyits have had important influence on man, animals, and plants. 16. Form of the Oceans. — The continents are clustered around the north polar region, with tongues projecting southward : the ocean water is centered around the south polar region, with triangular tongues projecting northward between the continents (Fig. 29). In outline the oceans are very irregular, because the irregular continents form their boundaries. We commonly recognize five oceans (Fig. 28). It is customary to choose an arbitrary boundary — the Antarctic circle — for the ice-laden Antarctic Ocean; but it is far better to consider as a great Southern Ocean (Fig. 29) all the Ocean: (1) the Indian Ocean^ which reaches up to Asia between Australia and Africa ; (2) the immense Pacifie^ which extends up between America, Australia, and Asia, to the point where America and Asia almost meet ; and (3) the Atlantic tongue, bounded by the Americas on one side and Africa and Europe on the other. The Atlantic is given an hour-glass shape by the narrowing wiiere the projection of South America reaches eastward toward that of Africa. The Arctic Ocean T h e n o r t h e rn hemisphere contains the greater part of the land, while the southern hemisphere is essentially a water hemisphere (Fig. 29). By choosing the proper circle, it is possible to so divide the earth a? center of the land hemisphere. Now that men no longer timidly skirt the coasts in small' boats, but steer boldly out to sea in great ships that visit every ocean, the needs of ocean navigation have led to the making of canals for short cuts across land barriers. For merly, vessels sailing from Europe to India went all the way around Africa ; now they take a short cut across the Isthmus of Suez (Fig. 535). Soon ships from eastern United States and Europe, bound for Asia or western United States, will make a short cut by way of the Isthmian Canal. Thus every day the oceans are becoming more useful. Summary. — 3Tost of the ocean water is in the southern hemisphere, three triangular tongues extending from the great Southern ocean northivard between the continents. The Arctic is a bay-like extension of the Atlantic. Topical Outline, Questions, and Suggestions. Topical Outline. — 8. The Atmosphere. — Extent; composition; proof of its existence ; importance, — life, fire, decay, diffusion of light and heat, hearing, winds, vapor, wind power; effects on land ; soil. 10. The Solid Earth. — Covering of sea floor ; of land; origin of soil; importance; depth; absence on steep slopes ; condition beneath the soil mantle ; valuable mineral substances. 11. The Earth's Interior. — Weight of material of outer part and of interior ; proofs of interior heat ; former belief ; earth's crust ; reasons for present belief ; effects of pressure ; former condition of earth ; future. 12. Air, Water, and Rock. — (a) States of matter: air, water, and rock illustrate the three states ; changes of each of these to the other two states. (b) Intermi;igling : rock and water in air ; water and air in earth ; air and rock material in water. 13. Irregularities of the Earth's Crust. — Average depth of ocean basins; average height of continents; proportion of plains ; distribution of mountains and volcanoes ; amount of irregularity of earth's surface ; cause of irregularities; changes in leveL importance of result upon man. 15. The Continents. — (^4) Characteristics: definition; real boundaries ; elevation ; surface features ; drainage ; relation of mountains to continent form — illustration. (B) North America: mountain systems; relation to continent form; to plains and plateaus; to irregular outline; effect of sinking of the land. (C) South America : mountains; outline; irregularities. (D) Africa : outline ; surface features ; coast line. (E) Australia: position; form; coast line. (F) Eurasia: relation between Europe and Asia; form of Eurasia; effect of mountains on coast line; of sinking of the land. (G) Influence of Continent Forms on Man : effect of separation ; of low elevation ; of coast line. 16. Form of the Oceans. — General form and outline; subdivisions of the ocean waters; boundaries of each; land and water hemispheres; value of oceans for navigation. Name some important effects of the air. 9. What influence has gravity on the oceans ? What is the area and depth of the oceans? Of what importance is the ocean for its animal products ; for navigation ; for its influence on climate ? 10. What covers the sea floor? The land? What is the origin of soil? Of what value is it? What is beneath it? Why is it sometimes absent? What valuable materials come from the solid earth? 11. What reasons are there for believing the earth's interior to be highly heated? Why is it no longer believed to be molten? What prevents it from melting? What is the earth's crust? 13. Compare the ocean depths and continent elevations. What is the general condition of ocean bottoms and continents? Where are mountains found? How many times greater is the earth's diameter than the height of Mt. Everest? What is the cause of these irregularities? 14. What agencies are attacking the land? What effect has this attack on the land? On the sea floor? What conflict is there between opposing forces ? How has this conflict been of importance to man ? 15. (^) What are the characteristics of a continent? What relation do the mountains have to the continent form? Give an illustration. {B) Explain the general form of North America. Explain the irregularities of the outline. Give instances illustrating each of the two causes for irregularities. (C) What are the characteristics of South America? (2)) Of Africa? {E) Of Australia? (F) What is the relation of 16. State the distribution of the ocean water : its general distribution ; the subdivisions, starting from the Southern Ocean ; the meaning of land and water hemispheres. What obstacles have been overcome? Suggestions. — (1) In a small jar seal up a plant, being careful to have it well watered, and see if it grows after the oxygen is exhausted. (2) Place a candle in a fruit jar, light it and see if it burns after the oxygen is used up. (3) Why are there holes beneath the flame of a lamp ? in it a smouldering piece of cloth. Explain the change that occurs. (5) How deep is the soil in your vicinity ? Find some cut — a cellar, railway cut, or stream valley, — where bed rock is seen beneath the soil. How thick is the soil ? Of what is it composed ? What kind of rock underlies it? Is the line between rock and soil a sharp line? (6) To illustrate the three states of matter : freeze some water. Melt the ice, then evaporate the water over the fire. Where does the water go ? Place some water in a shallow pan in a room and watch it from day to day. Where does it go ? What becomes of the water that 3''0u pour on plants? Of that sprinkled on the city pavements ? (7) Sth' mud and water together. Have you ever seen a stream resembling the muddy water ? Where did the mud come from ? Where was it being carried ? Soak it in water and weigh it again. Why the difference ? Most rocks will illustrate the same thing, but, being less porous, not so well as chalk. (9) Place some salt in water and stir it once in a while. Where has the salt gone? After twenty-four hours pour the water off and evaporate it. Do you find the salt? Chalk, marble, and many mineral substances will dissolve as the salt did, but in smaller quantities. (10) See if there are fossils in the rocks of your neighborhood. If so, find out if they once lived in the sea. What do they prove ? (11) In a shallow pan of water build three ridges of pebbles and clay, as high as you can, forming a triangular outline to represent the mountain skeleton of North America. With a sprinkling pot wear them partly down. Draw off the water with a siphon, then make a sketch map of the miniature continent, marking on it the position of the mountain ridges. Compare it with an outline m&p of North America. 17. Relation of Man to the Land. — In a railway journey from Atlantic City, east of Philadelphia, to Chicago a great variety of land forms may be seen. First the seashore ; then a lowland plain ; then a hilly country ; then a wild mountain region, with long ridges separated by broad valleys ; then a rugged plateau, with rivers deeply set between steeply rising, wooded banks ; then the open plains. Besides these large features many smaller ones are noticeable — rivers, creeks, brooks, rapids, waterfalls, floodplains, lakes, narrow gorges, broad valleys ; in fact, all the great variety of land forms to be found in a large area of diversified country. The careful observer will also note the following facts regarding settlement and industry. The steeper hill and mountain sides are still forested (Fig. 85), and lumbering is the only industry on their rocky slopes. Few houses are seen in the narrow, valleys, though here and there a fall has given the site to a mill, or even to a town; and, in a few places, there is some industry connected with the production of valuable minerals from the mountain rocks. On the other hand, the open plains and low hills, both to the east and west of the mountains, are everywhere inhabited ; houses are almost always in sight, woods are scattered, farms are seen -on every hand, and the land is dotted with villages, towns, and cities. This route passes three of the largest eleven cities in the United States, — Chicago the second in size, Philadelphia the third, and Pittsburg the eleventh. One is a sea port, one a lake port, and one a river port. These few facts indicate that there is a relation between the form of the land and the industries of the people. Every educated person should know the causes which operate to so modify the form of the land as to adapt it to different industries. This inquiry belongs to physical geography, or, as itis often called, physiography. To truly appreciate this subject it is necessary to carry our inquiry back far enough to understand some geological facts and principles ; and to this the present chapter is largely devoted. Summary. — There are great differences in the land surface from place to place, and consequently in the industries of man. Physical Geography, or Physiography, studies the causes for these differences and their relation to one another. 18. Rocks of the Crust. ^ — The many different kinds of rocks in the earth's crust are included in three large classes, — sedimentary, igneous, and metamorphic. (A) Sedimentary Hocks. — Rock fragments — pebbles, sand, and clay — are washed into seas and lakes by rain, rivers, and waves. They settle in the quiet water, the coarser fragments sinking to the bottom first. The motion of the water, agitated by waves and currents, keeps the finer fragments suspended for a longer time, and they therefore sink to the bottom farther from shore. Thus the water assorts the rock fragments according to size. On some days the waves and currents are weak, on others strong ; sometimes the rivers bring little sediment, at other times much. These differences in currents, and in materials supplied, cause the deposit of layers of different kinds, one on another. Each layer is of the kind that waves and currents are able to bring (Fig. 35). Such layers are called strata (singular, stratum'), and the rock is said to be stratified. Some strata are thin, others thick. Sometimes only one stratum is seen in a cliff, while in sibly shale, sandstone, conglomerate, and limestone. ^Vhen the sediment is deposited, it is loose and unconsolidated, like a gravel bank. The pressure of other layers, deposited above, and the action of percolating water, slowly bind the fragments together, forming solid rock. The percolating water dissolves mineral substances in one place, carries them on, and deposits some around the sediment grains. This binds, or cements, the rock Fig. 35. — To illustrate the deposit of sedimentary rocks. On the extreme left are coarse pehbles; on the extreme right, clay; in the middle, sand. Some layers of pebbles were dragged out to the sand area when the currents and waves were strong; and some sand layers were stratified with the clay strata. fragments together. The most common rock cements are the common soluble minerals, carbonate of lime, oxide of iron, and quartz. One may often see the process of cementing in a gravel bank (Fig. 32) where a white coating of carbonate of lime has been deposited on some of the pebbles. Summary. — Sedimentary rocks are in layers, or strata, formed by the assorting power of iva.ves and cnrrents, which vary in strength and carry finer particles farther from shore thaii the coarser particles. By pressure and the deposit of mineral ce'nients, the loose rock fragments are hound together, forming solid rock. (B) Igneous Roeks.^ — These rocks have risen from within the earth in a melted state. In some cases each eruption produces a lava flow, which cools to form a thick, massive layer of solid rock. In other cases the violence of the eruption blows the lava into bits of volcanic ash or porous pumice (Fig. 33). Lava and ash usually build a cone around the volcanic vent or neck (Fig. 34). Such beds are usually less regular and more massive than sedimentary strata. Much lava fails to reach the surface. Such intruded igneous rock is found in various positions, cutting across the sedimentary and other rocks. A narrow crack filled with lava forms a dike (Fig. 34) ; a mass of lava thrust between strata forms an intruded sheet or sill (Fig. 34) ; large, irregular masses, rising into the cores of mountains, form bosses (Fig. 34). Pikes Peak and many other peaks are bosses of hard granite rock (Fig. 33), brought to light by the wearing away of the layers into which they were intruded. Summary. — Igneous rocks are formed by the cooling of melted lava, some at the surface, in the form of lava flows and volcanic ash, some as intruded dikes, sheets, and bosses. (C) Metamorphic Hocks. — When subjected to great pressure, or heat, or both, rocks are changed, or metamorphosed. By metamorphism limestone is altered to marble ; shale to slate ; and sandstone to quartzite. The change may go so far that, as in the case of gneiss (Fig. 33) and schist, it is often impossible to tell the nature of the original rock. Metamorphic rocks are especially common among mountains where, during the mountain formation, the strata have been subjected to great pressure and heat. These changes have bent, folded, broken, and twisted the layers (Fig. 46), and often completely altered the rocks from their original condition. mountains, rocks are greatly altered or metamorphosed. (D) Resistance of Rochs. — All minerals, when exposed to the weather, are attacked by the elements ; but there is much difference in the rate at which different ones wear away. Quartz, for example (Appendix C), is liard, only slightlysoluble, and does not decay ; feldspar is hard and does not dissolve, but decays without great difficulty ; calcite is both soft and easily soluble. The rate of decay of rocks depends in large part on the kind of minerals of which they are composed. Sandstone and quartzite (Appendix C), made mainly of quartz, are usually very durable rocks ; and so is granite, which is mostly quartz and feldspar. On the other hand, limestone and marble, made of calcite, are easily destroyed. The decay of minerals and rocks is due largely to the action of water (p. 38). Hence dense and massive rocks, like gneiss and granite, are not so easily disintegrated as porous or friable ones, like shale and schist, into which water enters easily. Because of these facts weak rocks are ■»^/orn away, forming valleys, while durable rocks are left standing to form hills, ridges, and peaks (Fig. 38). Summary. — Some minerals and rocks are durable, others iveak. TJierefore, as the land wears down, valleys are formed where the rocks areiveak; hills, ridges, and peaks where they are more durable. 19. Changes in Level of the Land. — The old ideas, that the hills are everlasting and that the land is firm and stable, are now known to be incorrect. On the contrary, the land is ever changing. Hills are slowly wearing away, valleys are being deepened, and the waste is being carried to the sea. In addition to this, the crust of the earth is slowly rising in some places and sinking in others. By these movements sea bottoms have been raised to form parts of continents ; mountains have been formed ; and lands have been lowered beneath the sea. The explanation of these changes is the slow cooling and contraction of the heated interior (pp. 17 and 99). Evidence of such changes in level during past ages is abundantly preserved in the rocks. Beaches and coral reefs are found many feet above the sea; and fossil remains of ocean animals are entombed in the strata, even of mountains. There is also full proof that changes of level are now in progress. For example : a part of the Scandinavian peninsula, north of Stockholm, has risen 7 feet in 150 years ; the Netherlands are slowing sinking ; the coast of New Jersey is sinking at the rate of about 2 feet a century ; Eskimo houses in Greenland have been lowered into the sea ; the land around the Great Lakes is slowly rising ; and in 1822, and again in 1835, the coast of Chile was raised 2 to 4 feet. Hundreds of dmilar cases are known (Fig. 37). These changes of level are of two kinds : (1) rapid and local, where moiiutains are now growing, as in Japan and western South America ; and (2) slow and widespread, where large areas slowly swing up or down, as in northeastern America (p. 208). While in some places the lands are sinking, as a general rule they are rising. This has been true for long periods of the past ; and, as a result, the continents are very largely made of sedimentary strata that were deposited in ancient seas. Summary. — The surface of the land is slowly loearing aiuay; it is also being raised here and lowered there. There are both local rapid movements and a slow sivinging uj) or clown of large areas. On the whole, the continents have beeri rising, and this is why they are so largely made of sedimentary strata. by the disturbed mountain strata. A break in the rocks, accompanied by movement on one side, is known as 2^. fault (Figs. 36, 44). An arched upfold of the strata is known as an a>/^/c/me (Figs 39, 45); a downfold is a syndine (Fig. 40). In an anticline the rocks incline, or dip (Figs. During their uplift, rocks are often cracked by the strains. These cracks are called Jom^p/anes (Figs. 47, 75). The joint planes usually extend vertically into the strata, and consist of two sets, meeting nearly at right angles. Water readily enters along these Summary. — In plains and jilateaus the uiMfted stratified rocks are commonly left in nearly their original horizontal position ; hut in mountains they are folded and faulted. Joint planes , or natural planes of breakage, are also produced by the strains. 21. Agents of Weathering. — When exposed to the air, rocks crumble and fall apart as wood and nails do. This disintegration, or weathering^ is due to the action of various agencies, the most important of which are percolating water, air, and the action of animals and plants. These agencies do Fig. 43. — Horizontal strata in the West. A hard Ftg. 44. — A fault. Nolayer, standing out as a low cliff, may be seen in tice that the layers the foreground and far along the hillside. do not match on the FiQ 47. — Joint planes on the shores of Lake Cayno:a, New York. The two sets almost vertical, meet at nearly right angles. The smooth faces of the cliff' are due to the fact that the rock has cleaved away from it along the ^oint planes. 22. "Work of Underground Water. — A portion of each rain sinks into the soil, and part of it percolates into the rocks, for underground water is able to enter even the densest of rocks. Some of this water enters along joint planes (Figs. 51, 54) ; some between the Underground water find's many mineral substances which it is able to take away in solution. Its power of solution is greatly increased by carbon dioxide, and other substances, which it obtains from the air and from deca3dng vegetation. Aided by oxygen, carbon dioxide, and other substances, the underground water also causes changes in composition of many minerals. These changes are not very unlike that which causes a shiny nail, when exposed to dampness, to decay to a yellow, powdery iron rust. By these changes some substances are produced which the percolating water qan carry off in solution. The roots of plants seek and obtain Summary. — Water percolates into soil and even rock. It dissolves some minercds, changes others, and thus causes the rocks to disintegrate. In cold climates, frost also aids in disintegration. 23. Influence of Air in Weathering. — Warming causes rocks to expand, and cooling causes them to contract. A fire built against a rock, for example, causes it to expand and crack. In hot deserts the warming of rocks by day, and cooling by night, are important means of disintegrating them. The oxygen and carbon dioxide of the air, taken underground by water, help in the work of disintegration; they also cause changes in damp soil and rock at the surface. plaiifc food, the roots and tiny rootlets enter any crevice to be found (Fig. 53). On growing larger they exert such a pressure on the walls of the crevices as often to rupture them. In this way soil is pulverized and rocks broken apart. The ash left when wood is burned is largely mineral matter that the roots have taken as plant food. This proves that plants remove mineral substances from the soil and rock, and therefore that they help in disintegration. They aid also by supplying carbon dioxide and organic acids to water which, on soaking into the soil, passes through decaying vegetation. Animals are likewise effective agents of weathering. This is especially true of burrowing animals, such as earthworms, moles, ants, woodchucks, and prairie dogs. They stir up the soil* thus making it more open to the entrance of water ; tue^ oiia^ son to the surface, thus exposing it to the weather ; and some, like the earthworms, take soil into their stomachs, grinding it a little as .it passes through. Earthworms are among the most important of agents in soil preparation. Summary. — Weathering is aided by plant roots, ivJiicJi pry off fragmeiits and remove miyieral substances ; by carbon dioxide and organic acids, supplied from decaying vegetation ; and by the action lof biirrowing animals, esjjecicdly earthworms. 25. Rate of Weathering. — Because the weather has completely destroyed their form, it has been necessary to replace certain stone ornaments (gargoyles) that were placed on the Lincoln Cathedral, \n England, about seven centuries ago. On the other hand, delicate scratches on rocks, made by glaciers not less than 5000 years ago, are still perfectly preserved wherever they have been covered by a foot or two of soil (Fig. 289). These facts show that the rate of weathering is slow, but that it varies with circunistances. weathering. Some rocks disintegrate quickly, others slowly. Another cause for variation is climate. Where there is little moisture, as in deserts, there can be little change due to frost, solution, or decay, and weathering is, therefore, very slow. An obelisk (Fig. 50), which had stood for over 3000 years in the desert climate of Egypt, began to decay so rapidly when removed to the damp climate of New York that it was necessary to protect it with a glaze. In cold climates, frost action is very active ; in hot, damp climates the abundant vegetation supplies organic substances to the warm percolating water, greatly aiding it in its worl^ ment falls from the cliffs (Fig. 57) ; but, even in the most favorable places, weathering is so slow that one might see no great change in a lifetime. Centuries are required for great changes. Summary. — Even uyider the most favorable conditions, weathering is very sloio. Its rate varies with the rock, climate, exposure, and steepness of slope. Steep slopes are especially favorable because the falling away of loosened fragments leaves the rocks exposed. Fig. 54. — A steep peak in the high Alps wliere frost action is powerful. Notice the many cracks in the rock. Water enters along these, and every now and then a fragment hreaks away and falls to the hase. Fig. 56. — A diagram to illustrate the formation of residual soil. Notice that the soil is finer near the surface, where roots and earthworms penetrate, and that it grades downward into solid rock. to remove in solution. It is this that gives " hardness " to water, and the valuable properties to many mineral springs. One of the most common of these dissolved mineral substances is carbonate of lime, which supplies corals and shell-bearing animals with the lime from which beds of limestone are made in the sea. Rock fragments, loosened from cliffs by weathering, gather at the base, forming talus slopes (Figs. 67, 66). Occasionally jifreat masses are loosened, falling as landslides or avalanches (Figs. 58, 161, 162). There is also a very slow, almost imperceptible movement of rock fragments down even gentle slopes. It is this that makes the streams muddy. These rock fragments are used by the rivers as tools (Fig. 57) in cutting their valleys; and, on reaching the sea, they are deposited as beds of sedimentary rock (p. 32). By this removal of rock fragments and dissolved mineral substances, supplied by weathering, valleys are being slowly broadened. Finally, weathering is a delicate tool of rock sculpturing. It easily discovers which rocks are weak, and which durable; and, by removing the \Veaker rocks faster, it etches the durable strata into relief (Figs. 38, 59). The importance of this fact is more fully shown in later chapters. Summary. — Among the important results of iceathering not already described are, (1) the formation of residual soil, or soil of rock decay; (2) the supply of soluble mineral substances to tcater ; (3) the formation of talus and avalanches; (4) the supply of cutting tools to rivers; (5) the supply of materials for the formation of sedimentary strata; (6) valley broadening ; and (7) rock sculpturing. 27. The Agents of Erosion. — Besides weathering, which disintegrates the rock, thus preparing it for removal, there are several agents of erosion which remove and deposit rock fragments. The work of these agents is fully stated in other chapters and now requires mere mention. a number of houses. Fig. 59. — A view in the Colorado Canyon, where the clitls have been sculptured by weathering and erosion, bringing the hard roclcs into relief, and giving the softer strata more gentle slopes. CHANGES IN THE EARTH S CRUST. 45 to protect the soil ; (2) rivers (Chapter IV), everywhere at work removing materials supplied by weathering, and at the same time often deepening their own valleys with the rock fragments that they carry; (3) the oeean^ whose waves, tides, and currents attack the land along the coast (Chapter XI), and in which sediment washed from the land is deposited (pp. 33, 176) ; (4) lahes^ which resemble oceans (p. 220) ; and (5) glaciers (Chapter VIII), at present important only in high mountains and in the frigid zones. 28. Denudation. — The combined work of the agents of weathering and erosion may be called denudation. By denudation the lands are being sculptured (Fig. 59) and their general level lowered. If the material removed by the Mississippi River were taken equally from every part of its drainage area, the surface of the valley would be lowered one foot in 6000 years. Opposed to this tendency to wear the land away is the constant change in level of the land (p. 35), by which plains are being raised above the sea, plateaus made higher, and mountains uplifted (21). These uplifts are continually giving denudation new work to perform. Were it not for this elevation of the land, it is probable that the continents would have long since been reduced nearly to sea level ; for the age of the earth is very great. Summary. — Denudation is the combined icork of iveathering and erosion. It tends to lower the land; bat, though the age of the earth is great, frequent uplift has p>revented it from lowering the contineyits to the condition of a level plain. 29. Age of the Earth. ^ — No one knows how old the earth is. But all who have studied the question are agreed that it cannot be less than many millions of years, and most geologists hold that it must be at least a hundred million years. The evidence of this vast age cannot be stated in an elemen- understand why it seems a necessary conclusion. So slow is the work of denudation that a person living by a river side, or on the seashore, may see no notable change, even in a lifetime ; yet careful study will show that slow changes are in progress. Geological study has proved that slow changes have accomplished great results in the past ; and this could not have happened unless there had been a great length of time involved. Among these evidences of great changes are the following. The Colorado E-iver has slowly cut a canyon over a mile in depth. Lofty mountain ranges once existed where New York and Philadelphia now stand ; but they have been slowly worn away. Volcanoes ha "^v also been worn down to their very roots. To have slowly accomplished these great results demands vast periods of time. Sedimentary rocks furnish evidence leading to the same conclusion. It requires years for a layer of sediment a foot thick to be deposited; yet some sections reveal 40,000 feet of strata that were deposited in ancient seas. From these geological facts the conclusion that the earth is vastly old seems inevitable ; and the inference is supported by evidence furnished by physicists and biologists. Consequently, all geologists and physical geographers are now as convinced on this point, as astronomers are that the sun and stars are millions of miles away. To really appreciate the conclusions reached in the following pages, the student must start out with the same belief. Topical Outline. — 17. Relation of Man to the Land. — Changes noted on a railway journey: larger features ; smaller features; industries; cities; relation between land form and industries. the surface ; intruded into the crust. (C) Metamorphic rocks : cause ; results; metamorphisni in mountains. (D) Resistance of rocks: differences in minerals ; in rocks ; eifect on land form. 19. Changes in Level of the Land. — Slow wearing away ; movements of the crust; cause; proofs, — from rocks, from present changes; instances ; two classes of movements ; effect on continents. 20. Disturbance of the Strata. — Original position ; position in plains; in mountains ; fault; anticline; syncline ; dip; monocline; unsymmetrical fold ; overturned fold ; crumpling ; joint planes ; importance. 22. Work of Underground Water. — Entrance of water ; proof of its presence, — wells, plant roots, springs ; solution; substances aiding solution; changes in minerals ; result ; plant food; frost action. and carbon dioxide. 24. Organisms as Agents of Weathering. — (a) Plants : mechanical work of roots ; removal of mineral substances ; aid to underground water. (b) Animals: kinds; work done ; earthworms. 25. Rate of Weathering. — Illustrations of differences in rate ; effect of rock ; of climate, — arid, damp, cold, warm and damp ; of exposure, — ■ gentle slopes, steep slopes ; slowness of weathering. 26. Results of Weathering. — Residual soil; other soils; dissolved mineral substances ; talus ; avalanches ; supply of tools to streams ; formation of sedimentary strata ; valley broadening ; rock sculpturing. 18. What are the three divisions of rocks? (A) How are rock fragments assorted by water? What is the meaning of the terms strata, stratum, and stratified? How are stratified rocks consolidated ? (B) In what conditions are igneous rocks accumulated on the surface? Desci-ibe three kinds of igneous intrusions. (C) What is the nature of rnetamorphisra, and its results? Why is it so common in mountains? (D) How do minerals vary in durability ? What two conditions influence the rate of rock disintegration ? What effect has this on the form of the land ? 19. What changes are in progress on the earth's surface? What evidences are there of past and present changes of level ? What is the nature of these movements? What effect has this on the continents? 20. Why are the strata of plains commonly horizontal? What is the condition in mountains? Define fault; anticline; synciine; dip; monocline. Draw diagrams to illustrate symmetrical, un symmetrical, and overturned folds. What are joint j)lanes? Of what impo»'taiice are they? 22. How does underground water enter the rock='V What proofs are there of its presence? In what two ways does it work chemically in disintegrating the rocks? How does it work mechanically? sand, pebbles, and clay in the dish with water. Stir vigorously and let it settle. Sprinkle on the water a handful of sand, clay, and pebbles. (This experiment may be made even more effective if a mixture of sand, pebbles, and clay is made to represent land, then washed with a sprinkling pot into a glass aquarium partly filled with water.) Where does the finest material settle ? Are the layers horizontal ? Vary the rate of washing and observe what happens. (2) Even if the rocks and minerals in Appendix C are not studied, specimens of quartz, feldspar, calcite, sandstone, limestone, granite, and marble should be studied. The last four can be obtained readily, probably in a stone yard. The three minerals may be purchased from a mineral dealer for a very small sum. Do not get valuable specimens, but buy by the pound and break it up for class use. Study the characteristics mentioned in the Appendix. (3) Are the rocks of your neighborhood horizontal or tilted? If the latter, can you find folds or faults? Describe what you find. Look for joint planes and study them ; take their direction with a compass ; does water escape from them? Are there any quarries in which they are of use? (4) Find specimens of rock in the fields, or elsewhere, showing weathering. What signs of weathering do you find? Are there red or yellow stains? What causes them? (5) To prove that water expands on freezing, fill a bottle with water and freeze it. Even a toy cannon, plugged tightly, would break. (6) Place a thin piece of stone in a fire. Does it crack? Heat another small piece slowly, then cool it quickly by placing it in cold water. These experiments illustrate tUe expansion with heat and contraction with cold, though of course in nature the changes are not so great as this. (7) Look for illustrations of roots prying rocks apart. This may best be seen on cliffs where trees are growing. Tell what you see. (8) Watch the earthworms. The " casts " left when they are driven out of the swollen ground after a heavy rain are made of earth from their stomachs. What evidence do you find that earthworms help in weathering ? Darwin considered them of enough imj)ortance to write a book on them. (9) If you live in a glaciated country (Fig. 270), look for glacial scratches recently uncovered. Are they fresh? Why? Look for others uncovered for a longer time. Are they fresh? Why? (10) Study the soil of your vicinity carefully and tell its characteristics. (11) If you can find a cliff, look for a talus slope. Of what is it made ? Are the fragments angular or round ? Are they all of the same kind of rock as the cliff ? Have any fragments been removed by water? Have any fallen recently? Go there in spring, when the frost is coming out of the ground, and see if there have been recent falls. (12) If the water of your vicinity is hard, find out if mineral is deposited in tea kettles or in engine boilers. Perhaps the teacher of chemistry may suggest a way of proving that there is mineral in the water. (13) Are any of the streams that you know receiv ing rock waste from the valley sides? When does most come? Watch the streams to see. Does this sediment prove that denudation is now in progress? Would much change take place in a year? In a century? In a million years? Think of this carefully. Reference Books. — Lyell, Principles of Geology, 2 vols., Appleton, New York, 1877 (out of print), »\|8.00; Geikie, Text-hook of Geology, Macmillan Co., New York, 4th edition, 1903, $10.00 ; Dana, Manual of Geology, American Book Co., New York, 1895, $5.00 ; Leconte, Elements of Geology, Appleton & Co., New York, 1903, $4.00 ; Tarr, Elementary Geology, Macmillan Co., New York, 1902, $1.40; Scott, Introduction to Geology, Macmillan Co., New York, 1902, $1.90; Geikie, C7a.ss Book of Geology, Macmillan Co., New York, 1886, $1.10; Brigham, Textbook of Geology, Appleton & Co., New York, 1901, $1.40; [Merrill, Rocksy Rock Weathering, and Soils, Macmillan Co., New York, 1897, $4.00 ; Shaler, Origin and Nature of Soils (p. 219), 12th Annual, U. S. Geological Survey, Washington, D.C- RIVERS AND RIVER VALLEYS. 30. Supply of Water. — Part of the rain water returns to the air by evaporation, part sinks into the ground, and part runs off. That portion which passes back to the air need not be considered here. Most of that which sinks into the ground (p. 39), eventually returns to the surface by slow seepage and from springs. It may continue for months on its slow underground journey before finding conditions that favor its return to the surface. Were it not for this steady source of supply, after each rain rivers would quickly dry up. Then river navigation would be stopped, river water power would frequently fail, and the water supply of many cities would be cut off for a large part of the time. From a third to a fourth of the rain water runs off at the surface. Therefore every rain swells the volume of the streams, adding greatly to the steady supply from underground. When the snow melts or the rains are heavy, the rivers i^iay be quiokly transformed to raging torrents (Figs. 60, 61). The presence of the forest tends to reduce floods. Its dense undergrowth, the mat' of decayiug vegetation, and the tangle of roots seriously interfere with the run off of the water. There is a greater run off (1) during heavy rains than during long, slow drizzles ; (2) on clay soils than on sandy soils ; (3) ou frozen soils than on those with no frost. Some rivers have their water supply regulated. This is true of those whose supply comes chiefly from large and copious springs (p. 59). Lakes act as reguhating reservoirs, out of which streams flow with little change in volume ; thus the volume of Niagara is almost always the same. Swamps also help to regulate the water Fig. 62. — A rain-sculptured earth column in the Tyrol of Austria. The bowlder which caps it helps to protect the clay beneath. but the melting in summer greatly increases their volume. Summary. — Underground water gives to streams a steady sxijpply ; the rains and melting snows increase their volume. TJie forest, yiature of the rain, soils, and frost influence the run off. Springs^ lakesj swamps, and glaciers tend to regulate the volume of rivers. 31. Rain Sculpturing. — The surface of a road or a plowed field is often gullied by the washing action of rains and rain-born rills. The material removed is carried on toward the larger streams. In moist countries (Figs. 62, 63) this rain sculpturing is not usually so noticeable as in arid regions where there is little vegetation to protect the soil. Loose clayey soils are deeply gullied by the occasional heavy rains of arid regions ; but there is so little weathering that the steep slopes are not greatly rounded. Such rain-sculptured lands are known as Bad Lands, one of the largest sections being in South Dakota (Fig. 64). They are unfit for agriculture, and even for- cattle raising. Where the forest has been cleared for centuries, as in parts of Greece and Italy, rain sculpturing has destroyed much farm land. Summary. — In arid lands, and ivhere the forest has been removed, the land is sometimes so gullied by rain sculpturing as to unfit it for agriculture. In the West such regions are known as Bad Lands. 32. The Rock Load of Rivers. — To the mineral ]oad which is brought in solution by underground water (p. 39) is added some which the river water dissolves from its bed. This dissolved load is sometimes very noticeable, as when river water is "hard," or, as in southwestern United States, even, salt or alkaline. Fragments of rock, loosened by weathering (Figs. 57, 66), or washed in by the rain, are also carried by rivers. Water buoys up these suspended rock fragments so that they lose about one third of their weight. A current moving at the rate of one and a half or two miles an hour, that is about half as fast as a man walks, will transport small pebbles; one moving a quarter of a raile an hour carries only clay. Iq mountain torrents bowlders weighing hundreds of pounds are swept along ; but only sand and clay can be moved over level lowlands. These rock fragments are used as tools of erosion. The grinding of pebbles together rounds them and gradually wears them down to sand and clay ; and the river bed is also worn away, or eroded, by the grinding of these fragments against it. The load which rivers bear may be judged from the following. The Mississippi River annually carries to the sea 7,500,000,000 cubic feet of sediment. This would make a prism one mile square at the base and 268 feet high. It also carries 2,850,000,000 cubic feet of mineral matter in solution. Other rivers are bearing similar loads. From this it is evident that rivers are performing a great task in removing rock waste from the lands. Summary. — Rivers hear great loads of minerals in solution; also rock fragments, ivhose size varies ivith the velocity of the currents. Tliese are used as tools of erosion. lowering the land by removing the materials supplied by weathering and by rain wash. At some time in their history most of them are also at work in a vigorous attack on their channels. This work is both chemical (corrosive) and mechanical (corrasive), and it results in the formation of river valleys. Fig. 66. — The Gunnison River, Colorado. Rock fragments from the cliffs have made a talus, which, sliding into the river, supplies it with tools for work (see also Fig. 57) . A railway follows this narrow valley, one of its bridges being seen in the distance. To pass along this gorge it has to wind about, crossing the stream by bridges and tunneling the rocks. Fig. f;7.— a narrow gorge (Enfield) in central New York. One wall of a pot hole is seen in the foreground on the left. The stream course is here guided hy two joint planes which cause the smooth, straight walls hetweeu which the water is flowing. slide into the stream. In this way the valley is being broadened. Fig. 71. — Watkins Glen in central New York. A small stream is cutting this gorge deeper. It is a succession of rapids and cascades, at the base of which pot holes are being cut in the shale. One fairly large pot hole appears D the near foreground ; others are seen farther upstream. The rate of valley deepening varies greatly according to the rock, the slope, and the volume. A stream naturally cuts faster in soft than in hard rock ; on steep slopes than on gentle slopes ; with great volume than witii small volume. The effect of difference in volume may be seen in many streams, wliich at ordinary times do little work of erosion, but when in flood become powerful erosive agents (Fig. 61). Since sediment supplies rivers with cutting tools, this also has an important effect on river erosion. When there is little sediment, erosion is greatly reduced. For example, Niagara River emerges from Lake Erie as clear water, the sediment having been deposited in the lake. Therefore, down to the Falls, the river has been able to do very little toward cutting a valley (Fig. 483). The Colorado River, on the other hand, with a heavy load of sediment, has cut an enormous canyon (Figs. 1, 477), which it is still rapidly deepening. Other rivers, like the lower Mississippi, have more sediment than they can carry, and must deposit some of it, building up their beds. Rivers tliat are deepening their valleys are said to be degrading (Fig. 71), those that are building up their beds are aggrading their valleys (Fig. 112). Joint planes also influence the rate of erosion, and sometimes direct the course of a stream (Fig. 67). Ice (Fig. 68) is likewise of importance. In winter it diminishes the supply of water ; but in spring its melting adds to the floods ; and it pries and breaks off fragments of the rock and carries them along. Summary. — Rivers cut vertically on their beds, and laterally at their banks, the rate varyinr/ icith the rock, slope, volume, and sediment supply. Some ricers are aggrading, others degrading, their valleys. Joint planes and ice also iuftaence river ivork. rapids and falls. Most commonly it is a difference in hardness of the strata. Soft rocks are cut more rapidly than hard, and therefore rapids and falls occur where a degrading stream flows from a hard to a soft layer. Such falls are very common in regions of horizontal strata, where hard layers (Fig. 72) retard erosion while weaker layers beneath are removed. This undermines the hard layer, and when a piece breaks off, the fall retreats upstream (Fig. 75), always being located on the steep edge of the hard stratum (Fig. 74). There are thousands of illustrations of this, of which Niagara, located on a hard layer of limestone (Fig. 482), is the largest and best. Falls and rapids cause streams to concentrate their energy in spots. This is well illustrated by Niagara, where the falling water has .excavated a deep hole at the base of the fall. Similar holes, called pot holes (Figs. 67, 71, 73), are common in streams that are degrading their beds. They are enlarged and deepened by the whirl of water, which carries pebbles about with it. Pot-hole work is an important factor in the excavation of valleys. Waterfalls and rapids are of great importance in supplying power, the water being led through canals or pipes and allowed to fall upon a wheel which turns machinery. Now that electricity is used for power, falls are of value even in sparsely settled regions. Niagara Falls power, transmitted by wire, lights and runs the cars of Buffalo ; falls in the Alps and Sierra Nevada supply electric power for places miles away. Summary. — Falls and rapids, of use for icater poioer, are common where a degrading stream Jlows from a hard to a soft stratum, as at Niagara. Pot holes are excavated by the falling water. LIFE HISTORY OF A RIVER VALLEY A river valley, like an animal or plant, changes as it grows older. To understand these changes, or the life history of a river, it seems best to start with simple conditions — a plain of moderate elevation, with nearly horizontal strata, Fig. 72. — A hard layer of rock in a stream bed. When the water is higher there is a fall here, and the falling water removes the softer layer from beneath, undermining the hard stratum. Fig. 74.— Two diagrams to illustrate the history of a waterfall. In the left hand figure a hard stratum (the darkest) has a waterfall (W) over.its edge. As the falling water undermines this hard stratum the fall retreats upstream, always being located on the hard layer. At a later stage, therefore (right hand figure), the fall is farther upstream ; and falls are also present on the same layer in two tributaries. The stream erosion has formed a deep gorge below the fall, as in the case of Niagara. Fig. 75. — Taugnanuock Falls near Ithaca, New York, 220 feet high. The angles and smooth rock faces near the upper part, and the angle in the crest of the fall, are caused by Joint planes. A few years ago a huge block fell from the crest of the fall, giving its present shape; before that, the crest of the faU jM"ojected downstream. and a moist climate. Later study will show that many rivers depart from such an ideally simple condition ; but these variations will be better understood if we first study a simple case. Such a study will reveal some important laws of valley formation. drainage. The consequent streams quickly cut into the plain, forming narrow, steep-sided valleys (Fig. 76). As they degrade along their beds they discover differences in hardness of the strata, and therefore develop falls (Fig. 74) and rapids. At the same time weathering and meandering slightly widen the valley. There is a limit below wdiich no part of a stream may deepen its bed, and this is called its base level (Fig. 81). The sea is the permanent base level, and the down-cutting of every stream that enters the sea is arrested by it. Lakes act as temporary base levels ; but their effect does not last long, because the sediment that the streams bring, quickly fills and destroys them (p. 164). Fig, 7o. — A young stream valley on a plain. It is still well above base level ; tbe divides are flattopped ; there are few tributaries ; and lakes still exist. While the lakes are being filled and the valleys deepened, tributaries are developing. Little by little the tributary streams gnaw their way back from the main stream, narrowing the flat-topped divides and in time draining the level, swampy areas. A stream with these characteristics — steep-sided valleys, waterfalls, lakes, illy defined divides, and tributaries only partly developed — is a young stream. It has not had long to work, and consequently its valley is not thoroughly developed ; it is still growing. A young stream is better developed in its lower portion than above, as a young tree has a thick, strong trunk and delicate, growing branches. The Niagara Gorge (Fig. 483) and Colorado Canyon (Fig. 1) are good examples of young stream valleys (see also Figs. 77, 80) ; but no lakes remain in the course of the Colorado. Although such valleys are young, the time reqidred to perform even this much work is long, measured in years. A river may have been working for 5000 or even 50,000 years, and yet have a valley with the characteristics of youth. As in the case of plants, some of which grow old in a few days while others require weeks or even years, so in river valleys there is a great difference, under dif> ferent circumstances, in the time required to pass the stage of youth. Yet in all cases the features of youth are so distinct that a young valley is hardly more difficult to distinguish than a young plant. Summary. — A young river is one that has not had a long time for development. It, therefore, has a steep-sided valley, feiv tributaries, indefinite divides, and, if conditions favor, waterfalls and lakes. TJie term " youth " does 7iot refer to years, but, as in plants, to form. • 36. The Grade of a Stream. — The lowest grade to which a stream can cut its channel is one down which it is just able to carry its sediment load. The grade line is a curve, reaching base level at the river mouth and rising rapidly near the divide (Fig. 81). All streams that have not reached grade are working toward it, and young streams, which have a Fig. 77. — Narrow Rorge of a young stream cut in hard rock. Even here the valley has been widened somewhat by measoering and by weathering. The latter cause accounts for the breadth of tii« gorge at the top. Fig. 78. — Map of a part of the Florida plain where the swamps (indicated by *) and lakes have not yet been drained by the young streams (see Fig. 79), The lines are contour lines. The meaning of these is explained in Appendix T (Part of Citra, Fla.. Topographic Sheet. U. S. Geologicul Survey.) Pjq, 79. _ a ttat-copped, swampy divide in tlie Florida plain, on which the drainage is so young that the tributary streams have not had time to gnaw back and narrow the divide so as to drain the swamps (see Fig. 78). It often happens, however, that a stream has too gentle a grade to move its sediment load over. Then, to secure a steeper grade, deposit is made. Most streams on broad floodplains are thus aggrading their valleys. The broadening of the valley is first accomplished near the mouth ; but it slowly extends upstream. Young streams exist for a long time among the headwaters, as young twigs appear on the outer branches of even an old tree. In a mature stream, grade has been reached throughout most of its course, and any lakes that may have existed have long since been filled. Nor can there be waterfalls, because the graded stream is no longer cutting into the rock. Tributaries have developed in such numbers that the divides have become well defined, and all water that falls on the land finds slopes ready for it to flow down (Fig. 82). Again the comparison may be made to a tree, which at first has a trunk and few branches, but, as it grows older, develops an increasing number of minor branches and twigs. slopes and the amount of surface exposed to weathering are greatly increased (Fig. 84). These increasing slopes may supply so much sediment to the main streams that they cannot carry it all to the sea. They then begin to aggrade their courses to establish a steeper grade down which to mature. Fig. 84. — To illustrate the increase in slopes as valleys broaden. The line A A, drawn on the level surface of a young plain, gradually lengthens to JS £ as the valleys broaden to maturity. 38. Old Valleys. — As valleys grow older, the slopes become more and more gentle (Fig. 83) until the surface is reduced almost to sea level. An old land surface, reduced to the condition of a low, rolling surface, is called a peneplain (almost plain). Many parts of the continents are ancient enough to have become peneplains ; but there are numerous accidents which commonly interfere with this result. Of these accidents the most important are uplifts of the land, which continually give to streams new tasks to perform. Therefore, few valleys have passed the stage of maturity. Summary. — Old valleys are so broad that the surface is reduced almost to a plain, or to a p)eneplain ; but uplift of the land is so frequent that few regions have reached this condition. 39. Importance of Valley Form. — Young valleys encourage some of man's activities and interfere with others. The waterfalls furnish power; and the lakes are valuable for navigation, for their influence on the climate of neighboring land, and aii sources of food-fish and ice. On the other hand, land Fig. 85.— Railway crossing the Appalachians along one of the narrow, winding mountain valleys, so steep that the forest has not been removed. This valley has the form of late youth, or early maturity. cut by young valleys is difficult to cross, the valley bottoms furnish poor grades for roads and railways (Figs. 57, 66, 71, 77), and much of the country is unfitted for agriculture. In contrast to young valleys, mature valleys are the seats of agriculture, and their fertile floodplains are among the best farm lands of the world. Travel across country is easy, and the river valleys are important highways (Figs. 85, 86). Even the rivers themselves, if large, have so gentle a grade that they are navigable. Thus, flourishing farms and thriving towns and cities line the river banks and dot the slopes of mature valleys. This is well illustrated along the Mississippi valley, which offers a striking contrast to the young Colorado valley (Fig. 1). mature valleys are adapted to agriculture and dense settlement, 40. Springs and Underground Channels. — Where conditions are specially favorable, underground water (p. 39) is led back to the surface, appearing as a spring. Sometimes it comes out along a porous, sandy layer, sometimes along a joint plane. There are many springs along rivers ; but they occur also on hillsides and, in fact, wherever favorable conditions direct underground water to the surface. Some large and permanent springs rise from deep in the ground through fault planes, often bringing heated water to the surface. Such springs often have so much mineral in solution that they are known as mineral springs, and have important medicinal properties. The Hot Springs of Arkansas, and the mineral springs of Saratoga, Carlsbad, and Vichy, are examples of such springs. Water percolating through soluble rock, like limestone, dissolves the rock along joint planes and bedding planes. This often results in the formation of long, irregular underground valleys, or caverns, like that of Mammoth Cave, Ky. In such a country much of the drainage is underground (Fig. 87). There are large surface streams with few tributaries, the chief water supply coming from the springs (Fig. 88) that bring the cavern water to the surface. Entering such a cavern, one passes through a maze of dark, irregular j^assages, in which it is easy to lose oneself. From the roof hang stalactites (Figs. 87, 91) of carbonate of lime, which the water dissolved in its passage through the limestone rock and deposited on emerging into the cavern. In form they resemble icicles. Stalagmites (Fig. 91) are built up from the cavern floor by the dripping water, as ice columns are formed under a spout. Fig. 89. — To illustrate the formation of limestone caves. Water entering the sink holes has formed great vertical cavities, and also horizontal caverns through which it flows, emerging in the form of springs near the natural bridge on the right. and even beautiful forms. The surface of a limestone country is pitted with saucer-shaped depressions, known as si7ik holes (Fig. 90). Through these the water drains into the ground, though sometimes the entrance into the ground is clogged, changing the sink hole to a pond. Tliese sink holes are caused by settling of the ground, due to solution of the rock beneath (Fig. 89). Weathering, lowering the surface, slowly wears away the cavern roofs. Sometimes only a small part of the roof is left, spanning the valley as a natural bj^idge (Fig. 92). Summary. — Springs occur inhere conditions direct underground water to the surface, for example, a p)orous layer, a joint plane, fault ]jlai)i (many hot or mineral springs), or a cavern oxitlet. Caverns occur where underground water dissolves passageways through soluble rock like limestone. The water enters the ground through Fia. 94. — A small ox-bow curve in a meadow brook. A cut-off has been started, but brush was put in to stop it from (y^ntinuing. (L. O. Towne, Haverhill, Mass., Photographer.) 97, 102), against which the river cuts as it swings over the flood plain. These, being higher and drier than the floodplain, are often selected as the sites for towns and cities, as in the case of Vicksburg on the Mississippi. Broad floodplains are due to the fact that there is more sediment than can be carried down the grade. Therefore some must be deposited. When such rivers rise and overflow their banks, they submerge the neighboring lowland (Figs. 93, 99), and, with each flood, deposit a layer of sediment, as mud is deposited on a sidewalk when the gutter overflows. This slowly raises the level of the floodplain ; and, since it is being built by a broad sheet of water, its surface is made fairly level. Fig. 96. — Canadian river, Oklahoma. Througii this floodplain the river sweeps in great curves between bluffs which are seeu in the foreground and in the far distance. helps to keep them so. Their levelness and dampness further fit them for agriculture. In many arid regions the river water is led out over the floodplains for the purpose of irrigation, and in some arid regions, as along the Nile, the overflows themselves take the place of rainfall. A floodplain is usually highest near the river, because this part is most frequently reached by floods. This higher portion is known as the natural levee. On it are farms, towns, and cities; for example, New Orleans ; but behind it is a low, swampy tract, too wet for habitation. At New Orleans, the natural levee is trary, irregularities in the bed, and other causes, turn the current toward one side, and cause the stream to cut first at one are peculiarly favorable to Fig. 97. — To show by arrows how, in meanders, a river current cuts against one bank and deposits on the other. The bluffs are shown on the two sides of the floodplain. and abandons it Fig. 102. — The Missouri, a meandering river bordered by floodplain, and cutting at the base of its bluffs, wherever the current swings against them. Summary. — Large jloodplaiiis are level tracts of fertile alluvial land bordering rivers. They are bv.ilt during foods by the deposit of sediment, and are usually bordered by bluffs cut by the river. They are highest near the river, at the naturcd levee, on which artificial levees are built. Over the foodplain the river sivings m meandercurves, sometimes abandoning them, forming ox-bow cut-offs. 42. River Terraces. — The swinging of a river causes it to be first on one side of its valley, then on the other. If it is degrading, it cuts downward, now in one place, now in another. This leaves terraces, or narrow, flat-topped strips, each faced by a steep slope on the side toward the stream (Figs. 101, 103). If an unlift elevates a floodplain so that the river cuts down into it, a series of very perfect terraces is carved in the soft floodplain deposits. During the removal of any other kind of soft deposits, such as glacial and lake deposits, rivers also carve perfect terraces. 6est farm land in the Connecticut valley is terrace land. Summary. — River terraces are flat-topped strips of land ivith ^teep front, bordering rivers. Tliey are formed during the removal of materials, especially soft materials, by a degrading stream. The densest population of China and India is centered on the deltas and floodplains of the great rivers, and a large part of Holland is on the delta of the Rhine. The low ground, and the danger of floods from sea and river, make living in such situations dangerous. Millions of people in India and China have been drowned during floods; but the other attractions are so great that these river-made plains are densel}^ settled. Summary. — Deltas are level x>lains, built up by the deposit of sediment at river mouths; they are commonly triangular in shape because crossed by branching distributaries. They are especially well developed in lakes and other places ivhere the water is shallow, the bottom not sinking, and waves and currents not strong. Like Jloodplains, they form excellent farm land, and are densely settled. 44. Alluvial Fans. — A stream flowing from a steep to a more gentle slope has its velocity checked. If it has much sediment, some may be deposited where the slope changes (Fig. 109). Such a deposit is called a cone delta., or alluvial fan. Some are small, with steep slopes (Fig. 108); in fact, they may be seen forming at the base of clay banks after a rain ; and some are very large and fairly level, covering areas of thousands of square miles. They resemble deltas in their triangular outlines, and some of the larger ones are difficult to distinguish from deltas (Fig. 110). As in a delta, the water flows over an alluvial fan in numerous shifting distributaries (Figs. 108, 110, 111). As soon as one channel becomes too high, it is abandoned and a lower portion of the fan is built up. Thus the fan is built up regularl}^, because all parts of it are reached by the water. Mountainous arid lands are especially favorable to the formation of alluvial fans, because there are many steep slopes, much sediment, and usually a small amount of water. At times there are heavy floods, bringing much sediment ; but at other periods the water disappears by evaporation or by sinking into the gravel. Fi(}. 108. — Two alluvial fans being Duiit of gravel dropped at the end of sluices in the process of washing gold from the gravels. Notice the numerous branches of the stream on the farther fan. These are so rapidly depositing and building up the fan that they must frequently change positions. Allii^dal fans sometimes grow out across a valley, damming the main stream and forming a lake (Fig. 113). Tulare Lake in California (Fig. 114), for example, is caused by the low alluvial fan of King Eiver, which descends from the Sierra Nevada to the plain of the valley of the Hoangho of China (Fig. 110) is the seat of a dense agricultural population. The frequent shiftings of the river over this fan have caused enormous loss of life by drowning, and by the famines that have resulted from the destruction of crops. Even in a single flood over a million people have been killed. The Hoangho has even been used as a weapon of war, being turned out of its course to prevent an invading army from approaching. Summary. — Alluvial fans are delta-like deposits made ivhere streams descend from steep to gentle slopes, as at the base of mountains. Large alluvial fans are important agricultural lands. 45. The Filling of Valleys. — Many valleys are having their bottoms raised by the wash of sediment from their sides (Figs. Ill, 113). This is especially true in arid regions Fig. 110. — Map of the immense alluvial fan of the Hoangho. Measure with scale of miles the distance between the old and present month. valley among the mountains near Mt. A similar case is that of the Po valley in northern Italy. It was once an arm of the sea between the Alps and the Appennines, but it has been filled by wash from these mountains, and is still being built out into the Adriatic. The many mountain streams are forming low alluvial fans of coarse gravel near the mountains ; but near the Po the sediment is finer and the river is bordered by fertile farm laud, which is readily irrigated by water from the mountain streams and the Po. It is necessary to build dikes along many of the streams to prevent their overflowing the plain. Thus confined to their channels, the rivers are obliged to deposit sediment in their beds. In consequence of this, the surface of the Po is now well above the level of the surrounding country. tains sometimes deeply Jills valleys, especially in arid lands. Fig. 112. — The branching course of the Platte Kiver in Nebraska, which has so much sediment that it is aggrading its bed, and doing it so rapidly that it flows not in a channel, but in a braided series of branches. (Part of Kearney, Neb., Topographic Sheet, U. S. Geological Survey.) f'lo. 114. — Valley of California. The flat-bottomed valley is deeply filled with sediment washed in from the bordering mountains. Notice Tulare Lake formed by the low alluvial fan of King River. (From model made by N. F. Drake.) 33. Erosive Work of Rivers. — Nature of work ; corrosion ; corrasion ; lateral cutting; causes for variation in rate ; influence of sediment; degrading ; aggrading ; influence of joint planes ; of ice. 35. Young Stream Valleys. — (a) Initial drainage on a plain : lakes ; divides; tributaries ; consequent course, (b) Early stages of development: steep-sided valley; waterfalls; broadening of valley; base level; removal of lakes ; narrowing of divides, (c) Meaning of youth : characteristics ; illustration ; age in years ; comparison with plants. 40. Springs and Underground Channels. — (a) Springs : causes ; situation ; mineral springs, {b) Caverns: cause; underground drainage; outlets; stalactites; stalagmites; columns; sinkholes; natural bridges. 32. In what two forms is river load carried? How is each supplied? What is the effect of differences in current? What effect have the rock fragments on erosion ? Give an illustration of river load. 33. By what two means are rivers wearing at their channels? What effect have they on their banks ? State the several causes which influence the rate of river erosion. Define degrading and aggrading rivers. 35. What are the characteristics of new diiiinage on a plain ? What changes occur in valley form, lakes, tributaries, and divides? What is a consequent course? Base level? State the characteristics of young valleys. What does the term iJoulh mean? 37. What changes in valley form occur after a stream has reached grade? What about lakes and falls? What changes occur in tributaries? What influence does this have on sediment? 43. What is the cause of deltas ? Why so named ? What gives the delta form ? What conditions favor and what oppose their formation ? What about the population of deltas and floodplains? Suggestions. — (1) What is the source of the water of your nearest stream? Does it vary? Why? If there were no underground supply would it in any way affect you ? ("2) AVliere does the water run off most rapidly, on a road, a grass-covered lawn, or in the woods? Answer from your own observations. Why does it run off faster in one place than in another? From which place is most sediment washed to the streams? (3) Make a little channel in the ground and pour water into it, varying the amount from a small flow to a flood. Now make a small pond, say, five feet long, with the little channel for its outlet. Pour the same amount of water into the pond that you did into the channel. Does the outflow channel show the same variation in volume? (4) AVeigh a stone in the air with a spring balance. Weigh the same stone submerged in water on the end of a string. What does the result show? (5) INIake a little trough of rough wood and let water run through it from a faucet. On the bottom of the trough place small pebbles, sand, and claj^ Vary the velocity of the water to see what happens. Record your results. (6) Has the stream nearest you a rapid or slow flow? What is the size of the rock fragments that it carries at ordinary times? At times of flood? Why the difference? Is the material at the bottom coarser than that suspended in the current? Where do the rock fragments come from? (7) Are the streams near your home aggrading or degrading? Jf degrading, are tliey aggrading in some parts? Why? What differences in work do you see from time to time? Does rock structure influence the worlv ? Observe the stream in winter and spring to see if ice helps. Do you know of any places where they are cutting {>.e"ainst the banks? (8) Are there any falls or rapids? What causes them V Are there any pot holes? Find what is in the bottom. W'hat does this show? (9) Look for evidences of rain sculpturing on roads, in plow el fields, or under gutters. Place some flat pebbles on some clay and wash it away with a sprinkling pot. Are any columns formed? (10) Has the stream nearest you reached grade ? Is the valley young or mature ? Study and describe the valley, — its form, tributaries, divides, and falls and lakes (if present). AVhat influence has the valley on roads, railways, and industries? (11) Has -your river a floodplain ? Is the plain ever flooded? If so, go after the next flood to see if deposits of sediment have been made. Does the river meander? Have there been any changes in the meanders? (12) Terraces are common in sections where streams are cutting away glacial deposits. Are there any near your home? If so, study and describe them. (18) If there is a pond or lake near by, see if there are not deltas opposite the mouths of both the large and small streasns. If so, report on what you observe concerning their form and the material of which they are m;ide. (14) Are there any alluvial fans? Look for them in mud puddles at the base of a clay cliff, for example in a railway cut. You can make one by building a pile of clay with steep slope and washing the clay do"wn to the base with a sprinkling pot. Reference Books. — Russell, Rivera «f North America, Putnam's Sons, New York, 1898, r2.00 ; T ark, Physical Geography of New York State, Chapter V, :\Tacmillan Co., New York, 1902, $3.50; Hovey, Celehrated American Carerns, Robert Clarke Co., Cincinnati, 1896, $2.00; Shaler, Aspects of the Earth, Chapters HI and IV, Scribner's Sons, New York, 1900, $2.50; Huxley, Physiography, jNIacmillau Co., New York, 1891, $1.80. See also Chapter XVI of this book. PLAINS. 46. Continental Shelf Plains. — Off the coast of eastern North America there is a sea-bottom plain sloping out into deep water (Fig. 116). It attains a width of 50 or 100 miles, and its outer edge is covered by about 600 feet of water. The surface is a level expanse of sand near the coast, and of mud farther out. The plain is made of layer upon layer of sediment washed from the land, and the waves and currents are constantly adding to it. Other continents are bordered by similar sea-bottom plains, or continental shelves (Fig. 316). Should this sea bottom be raised 600 feet, a broad strip of plain would be added to the American continent. It would slope at the rate of a few feet a mile, and the rain that fell upon it would find such difficulty in passing off that much of the surface would be swampy. continental shelves, made of sediment from the land, 47. Coastal Plains. — Uplifts have actually added such plains to the land (Figs. 122, 123). Some are narrow strips at the base of mountains, as in western South America (Fig. 117), where the land is still rising ; others are many miles wide, like the plain that skirts the coast south of New York. Because they border the coast they are called coastal plains. Tlie coastal plain of the Atlantic and Gulf coasts extends from New Jersey to the Rio Grande, and includes the peninsula of Florida. Wells bored into it pass through hundreds of feet of gravel, sand, and clay, often finding water in the Fig. 118. — Diascram to illustrate the cause for artesian wells on a coastal p.uiii. Water passes down the porous layer P, and is prevented from rising; or going deeper by the impervious layers, /, I. When a well is bored down to tht porous layer the water rises to the surface because it has entered higher than the outlet of the well, and is under pressure of the water in the porous layer, which, therefore, forces it out. Such a well may even be bored on a sand bar in the sea, finding water beneath the impervious layer. ducing fruit, grain, etc., in Maryland, Delaware, and other Fig. 123. — Same as Fig. 122, elevated to form a coastal plain. Rivers from the old land are extended out upon the coastal plain. This is the condition of the coastal plain southward from New York. being useful in the South for rice culture. A slight sinking of this coastal plain has admitted the sea into the valleys, transforming their mouths to shallow bays (Figs. many. The shallower bays and tide-water rivers are navigable b}' small craft, thus opening up large areas of country to water transportation. This has helped greatly in carrying cotton and For the most part the rivers of the coastal plain are sluggish, and, in some places, the slope of the plain is so gentle that water does not run off. This causes swamps, as in parts of Florida (Figs. 78, 79, 119), and the Dismal Swamp (Fig. 307). In Texas, south of Houston, the divides are so flat and swampy tliat there is no agriculture, and not even cattle can find support. Tlie surface of the Florida plain is so young, and the streams have so little sediment, that the shallow lakes in depressions of the old sea bottom have not yet been filled. Where the streams have cut into this coastal plain tliey occupy shallow, steep-sided valleys, with broad, flat-topped divides (Fig. 121), along whose le\el surface the roads run. Where streams pass from the older land to the coastal plain (Fig. 123), tlieir slopes increase and their courses are interrupted by rapids and falls. The explanation of this fact is that the rivers have cut faster in the soft clays and sands of the plain than in the harder rocks of the old land. Fcr this reason the boundary between the old land and the plain is called the Fall Line (Fig. 125). It has had a very important influence on settlement. Even in the days of the Indians, village sites on the rivers were located along this line, — the highest points to which canoes could go from the seaward side, and where portages were necessary to pass higher upstream. White men have located cities on these same spots, the farthest points to which boats from the sea can pass inLand. Columbia, and Augusta. Summary. — Upraised sea bottoms form coastal plains slcirting the coasts of continerits. There is a ivell-clejiiied one from New Jersey to Mexico, much of ichose level surface is too sandy or swampy for agriculture, while in Florida there are many lakes still occupying the original depressions. A slight sinking has admitted the sea into the river mouths, transforming them to shallow bays. Where streams descend from the old land to the plain there is a line of rapids and falls, called the Fall Line. 48. The Russian and Siberian Plains. — This, the greatest expanse of plains on any continent (Fig. 21), covers an area far greater than the entire United States. These plains extend from the Caspian region to the Arctic, including a large part of northern Asia and much of Russia, with a western branch reaching to Holland. They are made of layers of sand, gravel, and clay, washed from the mountains of Asia and Europe into a sea which has been destroyed by uplift. The uplift of this sea-bottom plain has been so recent that the streams are young ; there are many swamps ; shallow lakes are yet unfilled ; and the divides are flat-topped. In the North there is barren tundra, inhabited by scattered tribes (Fig. 126) who use the reindeer as a domestic animal (Fig. 546). The soil, frozen to great depth, thaws in summer only at the surface, making the land a vast swamp ; in winter the tundra is a bleak, frozen, snow-covered desert. Toward the south it grades into the forest region which is now being cleared and opened to agriculture as a result of the building a^ the Siberian railway. This forest section is destined to become one of the great farming regions of the world. On its southern side the forest belt grades into the open, grass-covered steppes (p. 285), a region too arid for farming, and, therefore, occupied by a nomadic, pastoral people. Summary: — Vast plains, caused hy recent uplift &f an ancient sea bottom, occupy a large part of northern Asia and Europe. There is harr en, frozen tundra in the north, barren, arid steppe land in the south, and forest and farm land between. ancient geological times a sea bottom between the mountains of eastern and western North America was also raised above sea level. From time to time it has been reelevated, and numerous additions have been made to its southern margin. Denudation has also been at work, lowering and sculpturing its surface, so that in places it is hilly. It forms one of the largest areas of plains in the world (Fig. 21). Near the Appalachian Mountains the plains reach an elevation of 2000 to 3000 feet ; near the Rocky Mountains they rise from 5000 to 6000 feet above sea level. From these higher portions, really plateaus, the surface slopes toward the Mississippi, making a broad valley which that river follows, receiving long tributaries down the slopes from either side. PLAINS, PLATEAUS, AND DESERTS. 77 The plains west of the Mississippi are called the Great Plains (Figs. 127-129). In the eastern part tliey have rainfall enough for agriculture ; but west of the 100th meridian they are suited only to grazing, though here and there rivers and artesian wells supply water for irrigation. Where the rainfall is light there is timber only along the streams. In early days, when Indians occupied them, crossing these vast plains was a difficult and dangerous undertaking. East of the Mississippi are large areas of plain, called prairies, which, when discovered, were also free from forest. In some cases the treeless condition was due to fires, set by Indians in their buffalo hunts. In others the fine-grained soil seems to have been unfavorable to tree growth, but favorable to a luxuriant growth of prairie grass. These fertile, treeless prairies helped greatly in the settlement of the Middle West. A crop could be raised the first year, for there was no laborious work of clearing land for farming ; and, when this was found out, settlers came rapidly and prospered. Plains are not usually great mineral-producing regions, but are especially suited to agriculture when the climate is moist, and to grazing when arid. Yet, in the plains of central United States, beds of sandstone and limestone furnish abundant building stone ; layers of salt are found ; deposits of iron, lead, and zinc occur ; and there are vast quantities of natural gas, petroleum, and coal. Where coal is present, busy manufacturing cities spring up, especially if agriculture flourishes, supplying materials for manufacture and a market for manufactured products. These conditions all exist on the plains of central United States. Each of the continents has plains similar to those already described. The great plains of the Amazon, of Argentina, and of Venezuela are instances. A very large part of the land surface consists of plains (Fig. 21) that at one period or another have been raised from the sea. Summary. — TJie ancient and much worn plains of central United States slope from the mountains on each side, forming the great Mississipjyi valley. In the West the Great Plains are treeless, because arid ; in the East, though the climate is moist, large areas, called prairies, were treeless because of the effect of fires ayid the compact soil. These plains, adapted to agriculture where humid, and grazing where arid, also contain mineral wealth, and, in the humid portion, have become a prosperous and busy manufacturing region. 130), larger than all the Great Lakes combined, existed in the valley of the Red River of the North. The fine-grained sediment that was deposited on the bottom of this extinct lake has made a fertile plain (Figs. 131, 132), one of the most famous wheat regions of the world. Its surface is so smooth that, after a rain, water stands on the ground in sheets. A large lake also once existed in the Great Basin, round Great Salt Lake. When the climate became arid this lake was diminished by evaporation, leaving only small remnants, of which Great Salt Lake is the largest. These remnants occupy shallow depressions in the level lake-bottom plain (Figs. 133, 150, 301). There are a number ,of other classes of plains. Some of these are described in the chapters on Glaciers (p. 149) and Lakes (p. 165) . Others, formed by rivers, have already been described, — tlood plains (p. 61), delta plains (p. 64), alluvial fan plains (p. 66), and filled valley plains (p. 67). Summary. — On lake bottoms sediment makes plains which may become dry land by the disappearance of the lakes, as in the valley of the Red River of the North, and the Greed Basin. are found. In time the lakes are filled, grade is established, falls disappear, tributaries increase in number, divides narrow up, and the valleys broaden (p. 57). Such a mature plaiii has an undulating surface, and, if high, it may be so dissected as to become a hilly laud (tig. 134). In an old plain the valleys are so broadened that the surface again becomes nearly level. The rock layers of a plain usually lie in sheets, gently inclined in the direction given them by uplift of the land (Fig. 118). As the surface of the plain is slowly worn down, durable layers, since they resist deimdation better than weak ones, are left as uplands, possibly only a few feet, perhaps scores of feet, above the lower portions of the plain. Being in sheets, the durable layers form belts of hilly land bounded on either side by belts of lower land, where the weaker strata lie (Fig. 135). The plain is, therefore, sculptured into bands, or belts, of different level, corresponding strata. Fig. 135. — A belted coastal plain. The different symbols (dots and lines) represent different layers of rock, gently inclined toward us. PLATEAUS. 52. Nature of Plateaus. — When mountains are nj^lifted the country on either sic^e is also raised, often without much folding of the strata. As the mountains rise higher the adjoining plains become more elevated, especially near the mountains and between the ranges. They may rise so high that they deserve the name plateaus, for a plateau is only an elevated plain. The plateau along the western base of the Appalachians (Fig. 146) is 2000 to 3000 feet above sea level; at the eastern base of theRocky Mts. (Fig. 129), from 5000 to 6000 feet; between the Rockies and the Sierra Nevada, often 7000 to 8000 feet; north of the Himalayas (Fig. 136), over 10,000 feet. Owing to the close relation between plateaus and mountains (Fig. 136), the strata of plateaus, though mostly horizontal, are sometimes broken and tilted; in fact, there is every gradation from slightly tilted plateau blocks (Fig. 155) to true mountains. Lava has often welled from the fissures, flooding large areas of country, as in the Columbia and Snake River valleys (Fig. 476). uplift, with strata usually horizontal, though sometimes tilted. 53. Sculpturing of Plateaus. — Rivers upon plateaus have much the same history as upon plains (p. 54); and the life history of a plateau is much the same as that of a plain (p. 79). But, being higher above base level, the streams have more work to perform, and this takes a longer time. Young streams sculpture plateaus into extremely rugged form, with flat-topped divides, and deep, steep-sided valleys, with falls and rapids. The valleys grow broader, the surface lower, and finally, in old age, the land is level again. For this reason many arid land plateaus are still in the rugged stage of youth, even though in years they may be far older than maturely dissected plateaus of humid regions. For the same reason arid plateaus have an angular topography (Figs. 140, 148), while in moist climates denudation more commonly rounds the edges of the strata. prolongs youth. 54. Canyons. — A canyon is the deep, steep-sided valley of a young plateau stream (Figs. 137, 138). Canyons are found on most plateaus, being a characteristic result of the early stages of river erosion in high plateaus. By far the best instance is the Grand Canyon of the Colorado. (Frontispiece ,see also p. 322.) For about 200 miles the Colorado River flows in a canyon, in one place 6000 feet in depth — the deepest canyon in the world. Some, of the grandest scenes in nature are the views looking down into this river-made valley from the canyon venturesome trip through the canyon. 55. Mesas and Buttes. — In plateaus there are many flat, table-like surfaces (Fig. 140) faced by steep slopes, often cliffs. These are mesas^ a Spanish word meaning table. An examination of such a mesa shows that the rock on the top is hard, often lava. These table-top surfaces are due to the fact that the more durable rock layers have resisted denudation ; and, since they are nearly horizontal, have held the surface up to a general level, parallel to the stratification. Fig. 140. —Mesa Verde, Colorado. The horizontal hard stratum that protects these mesas from being worn away has a steep slope, while the softer strata beneath have a more gentle slope. strata of a plateau. FiG. 143. — A rejuvenated river. In the left-hand fifjure the stream has reached grade and is swinging over a floodplain in a gently sloping, mature valley. In the right-hand figure the land has been uplifted and a young valley is sunk in the bottom of the mature valley, preserving some of the meanders that the stream had before the uplift. These may be called entrenched meanders. Small detached sections of mesas, cut off by denudation, are called buttes (Figs. 141, 144). They, too, are capped by durable layers which have preserved thera from being worn down. The pres- 56. Superimposed and Rejuvenated Rivers. — In cutting into the strata of plains and plateaus, rivers may wear down through the horizontal layers to buried mountains (Fig. 123). Such rivers are uaid to be sujyerimposed on the buried structure (Fig. 142). The Colorado River, for example, has discovered an old, buried mountain mass in one part of its canyon. An uplift of the land gives a river new life, or rejuvenates it. The stream then cuts a narrow gorge in the bottom of its old valley (Fig. 143). Such a valley is rejuvenated, or made young again. Summary. — Superimposed rivers are those tchich cut through one set of layers to another of different position. A r^uvenated river is me made young again by any cause, as by uplift. plateau of Mexico, for instance, the climate is tropical at the base ; coffee is grown on the lower slopes; but grains are the chief crops on top. In the lower Colorado valley, in Arizona, the summer climate is almost unbearably hot, wliile on the plateau it is pleasantly cool. The plateau of Tibet is so high that it has a cold, disagreeable climate, even in summer. Plateaus are often associated with mountains, which shut out the rain-bearing winds. Many plateaus are therefore arid, and some, like central Asia and parts of western United States, are true deserts. 58. Inhabitants of Moist Plateaus. — The plateau at the western base of the Appalachians (p. 80) includes the Catskill, Alleghany, and Cumberland mountains. It is dissected by valleys, often 1000 feet deep (Fig. 145), with sides too steep for cultivation, but, owing to the moist climate, clothed with forest (Fig. 146). There are no true buttes and mesas, and no real canyons ; but the surface is, nevertheless, very rugged. Much of this plateau is a wild region, with a sparse population, and with its forest areas still occupied by wild animals. It is an important source of timber. The scattered farms are poor and, south of Pennsylvania, where the rugged, timber-covered surface interferes with communication with the outer world, there are sections in which the people are very backward. Many cannot read or write; illicit distilling of whisky is one of the industries; and, in some parts, there are family feuds and lawlessness, resulting in much loss of life. The discoverv of coal has led to the opening of parts of this plateau tcr other occupations than lumbering and the crude farming of the backwoodsmen. In this respect the plateau of western Pennsylvania has advanced far beyond that of West Virginia, Tennessee, and Kentucky. In New York (Fig. 145) the plateau is less rugged, and, consequently, better developed. It lias, in large part, been cleared of forest, and farm lands have been developed wherever possible. Yet even here the upland farms are poor in quality. Summary. — Rugged, dissected plateaus in moist countries, like :hat ivest of the Appalachians, are largely forest-covered, poorly .tdapted to farming, and, unless influenced by the development of mineral resources, are apt to be occupied by a sparse population, little infuencei by the outside ivorld. 59. Inhabitants of Arid Plateaus. — Because of their ruggedness, coldness, and dryness, arid plateaus are sparsely settled. In the West, large areas of plateau are almost uninhabited except by ranchmen, whose cattle and sheep feed on the sparse growth of grass (Figs. 127, 128). Because of the dryness there is little farming, except near the mountains where alluvial fans and level portions of the plateau are irrigated by water from the mountain streams. The bottoms of the canyons are rarely wide enough for farms, and it is usually impossible to lead the water out for use in irris^ation. The Indians who occupied the arid plateau of southwestern United States farmed by means of irrigation For protection from roaming bands of more savage Indians, they often built their homes, or pueblos, on the buttes and mesas, which they resemble in color and form. From them they could look out over the country, and be partly protected from enemies by the steepness of -^he bordering cliffs. Some Indians (Fig. 148) still live in these situations. Other Indians lived in caves in the cliffs, and still others under overhanging ledges, where weather and wind had removed weaker rocks from beneath the more durable ledges. The latter are called cliff dwellers, the former cave dwellers. These habitations are no longer occupied. DESERTS. 60. Nature of Deserts. — ^ A desert is a region in which few forms of life can find sustenance. Thus, by reason of cold, the vast expanse of ice in Greenland is a desert ; indeed, it is such a one that, in a large part of its area, no animal or plant can live. The term desert is, however, commonly applied to those lands on which there is so little rainfall that only a few especially adapted animals and plants can live. About one fifth of the land has an annual rainfall of less than ten inches and is, therefore, desert ; and fully as much more is arid, having too little rain for agriculture. ^ It is a mistake to suppose that no rain falls in deserts, for there is no land on the earth so desert that it does not have some rainfall. One of the driest deserts is in southern Peru, where, close by the Pacific, a period of seven years has elapsed between rains. Nor is it correct to imagine deserts as dreary wastes of sand and monotonous expanses of plains. It is true that there is much drifting sand, and that most deserts are either plains or plateaus ; but deserts also have many bare, rocky slopes, and even mountains (Figs. 150152). Where the mountains rise high enough, rain falls on their slopes, streams flow down their valleys, and forests clothe their sides. Summary. — Deserts are due to cold, and to lack of rain, tJiongh even the driest have some rainfall. Most deserts are ^ilains and plateaus, ivith imich sand, though there are also mountains and raany hare, rocky slopes. 61. Drainage of Deserts. — With so little rain there is naturally little drainage. Most of the rainfall either quickly evaporates from the surface or sinks into the soil; but a heayy rain is followed by a rapid run off, because there is little vegetation to check the flow of the water. Heavy rains, known as " cloudbursts,'^ sometimes occur, especially in the Because of these sudden floods, it is dangerous to camp in a dried-up stream bed, or arroyo. Kail ways crossing deserts are often damaged by these floods ; crops and houses are washed away ; and vast quantities of sediment are brought down. This forms alluvial fans, often very stony near the mountains. It may be months or even years between rains, so that desert streams are typically intermittent. Those from the mountains have a more regular flow, and some have so large and steady a water supply that the}^ are able to maintain their course entirely across a desert. Thus the Colorado River and the Nile, fed from distant mountains, flow across deserts to the sea. Most desert streams carry so little water that they lose themselves, or waste away, a few hundred yards, or a few miles, fronthe base of the mountains in which they are born. Sometimes they terminate in a salt marsh, or saline; sometimes in an alkali flat (p. 169) ; sometimes, when there is enough water, in salt lakes. The alkali and salt are brought in small quantities, dissolved ir the water, and left when it evaporates.' Where salt lakes formerh existed, and on the salines and alkali flats, there are barren and desolate areas of glistening salt or alkali. Summary. — Most desert streams are intermittent and subject to occasional Hoods; but some large rivers^ fed amoiig the mountains, maintain their course across the desert. Many streams waste away on the desert and end in salt lakes, salines, and alkali flats. 62. Wind Work on Deserts. — On deserts the work of the wind (Fig. 147) is more important than that of water. Small dust whirlwinds are common on hot summer days, and even moderate winds drift the sand and dust along the surface. Violent winds raise the sand in the air, causing fierce dust storms which obscure the sky and land, and even endanger life. During such a wind the movement of the sand may entirely change the details of the land surface. The finer dust is often drifted far away, dust from the Sahara having settled in central Europe and on ships west of Africa-. It is this wind work that j)iles up the sand which every onf associates with deserts. The sand is made of small rock fragments weathered from the cliifs (Fig. 151), and brought down by the streams. It is drifted about, and gathered into vast areas of sand dunes, which are so difficult to cross that, wherever possible, caravan routes carefLdly avoid them. The sand dune hills may reach a height of several hundred feet, though usually they are tnuch lower. western United States, on the Mexican boundary. The front is steep on the side away from the wind, and the surface is rippled with sand waves (Fig. 147), formed by movement of the sand before the wind. Sand dune hills slowly change form and position, and cities in central Asia have been buried by their advance. Summary, — Winds move the small rock fragments about, accumwlatirig the sand in favorable positions, thus forming belts of sand dunes which are ever changing in form a7id position. and sparseness of the population are unfavorable to the development of mineral deposits, and there is little opportunit} for other industries. The rainfall is too lisfht for aofriculture without irrigation, and only a few parts have a water supply for irrigation. Areas which have water are called oases (Fig. 152) ; these are usually either scattered springs in the desert, or else places where streams descend from mountain canyons and flow out upon alluvial fans. A large stream, like the Nile or Euphrates, causes a large oasis which may support an enormous agricultural population. A few scattered people find life possible in all the desert lands. In the Old World the desert jjeople (Fig. 526) are nomads, or wanderers, who move with their herds from oasis to oasis^ to give the animals a chance to feed on the sparse desert vegetation. Such a life of danger and privation develops a hardy, warlike people, with love of freedom and a contempt for the monotonous settled life of the farmer. These people, having learned how to use the camel (Fig. 519), " the ship of the desert," for carrying their burdens, have long been traders and caravan leaders across the deserts. For centuries the chief means of communication between the east and west of the Old World was by caravan. Many of the Bible descriptions refer to desert life, for Palestine is surrounded by desert and is on caravan routes. Summary. — Except on the oases, deserts are unfavorable to settlement, being occiqned, in the Old World, by a scattered nomadic population, engaged in herding and in caravan trade by use of the camel. 47. Coastal Plains. — (a) Origin and instances, (b) Atlantic coastal plain: extent; structure; artesian wells, (c) Agriculture: sandy soil; higher lands; swamplands. ((/) Coast lii^ie: effect of sinking ; fishing; sand bars ; navigation, (e) Rivers : swamps ; lakes ; young valleys. (/) Fall Line : cause ; Indian settlements ; location of cities. 49. Plains and Prairies of Central United States. — (a) General fea^ tures : origin; later changes; elevation; slopes; influence on Mississippi. (b) Great Plains: climate; grazing; agriculture; timber, (c) Prairies: cause; influence on settlement, (d) Mineral deposits: kinds; influence on manufacturing, (e) Other great plains. 61. Drainage of Deserts. — Rainfall; runoff; "cloud-bursts"; arroyos; effects of floods ; intermittent streams ; large streams fed from mountains ; withered streams ; salines ; alkali flats ; salt lakes ; cause. 47. Where are coastal plains found ? Why? Why is artesian water found in them ? What industries are developed on the Atlantic coastal plain? What is the nature of the coast line? Why? What are the evidences of youth? What are the cause and effects of the Fall Line V 48. What is the extent of the Russian and Siberian plains? Yvluit is their origin ? What proof is there of youth ? What are the conditions in the northern, central, and southern portions? 49. What is the general condition of the plains of central United States ? What are the conditions on the Great Plains ? Why are the prairies treeless? What effect has this condition had? Account for the development of the central plains region. Where else are similar plains found? 58. What is the condition of the plateau west of the Appalachians ? What effect has this on the people? What differences are there from Tennessee to Nev7 York ? Why ? Suggestions. — (1) Make a coastal plain. In a shallow dish make an irregular land surface of clay. Have one portion hilly to represent land, the other part low. Fill the lower portion with water. With a sprinkling pot carefully wash some of the land into the depression, then drain off the water with a siphon. Notice the marginal plain that is built off the land. It is a fair miniature of a coastal plain. Is it perfectly ievel? What irregularities are there? Why? (2) In the same dish mold a basin of clay, and drop pebbles on the bottom to represent hills. Partly fill with water. Sprinkle clay into the water, and, after it has settled, draw off the water. If clay enough has been added the bottom will be level, quite like a drained lake. What is the nature of this bottom? How does it compare wdth those described in the text? The conditions which existed in the Great Salt Lake region can be imitated by allowing the water to evaporate, instead of drawing it off. The condition in the Red River valley can be imitated by making one side of the basin of packed snow or ice and allowing it to melt, thus draining the lake. (3) Make a basin similar to the above, but use salt water (dissolviiLg salt in the water before pouring it in). Then allow it to evaporate. What is the result? This is similar to the conditions which have caused many beds of salt, for example, those of New York, Michigan, Kansas, and the Far West. (4) To make an artesian well. Extend the clay down over the lower edge and the two sides of the pebble layer, making it so tight that water will not seep through easily. Pour water in at the upper edge of the pebble layer. Now, near the lower end of the board, insert a glass tube six inches long down to the pebble layer (it will be well to leave a small hole in the cloth for this purpose). The water should flow out of the tube as an artesian well does. (5) Make a small plain of clay, sloping in one direction, and slowly sprinkle it with a spray of water. Watch carefully and describe every stage in the wearing away of the plain. (6) Make a much higher plain, to represent a plateau, and note the difference between the wearing away of the two. If a very thin layer is made with a little plaster of paris in it (not too firmly cemented), buttes and mesas may be made by sprinkling. (7) Map studies are suggested in Appendix J. Reference Books. — Tarr, Physical Geography of New York State, Chap. Ill, Macmillan Co., New York, 1902, $3.50; Chamberlain, Artesian Wells, 5th Annual U. S. Geological Survey, p. 131 ; Salisbury, The Physical Geography of New Jersey, New Jersey Geological Survey, Trenton, N.J., 1895 ; Abbe, Physiography of Maryland, Vol. I, Part II, Maryland Weather Service, Baltimore, Md., 1899; Campbell and Mendenhall, West Virginia Plateau, 17th Annual U. S. Geological Survey, p. 480; Powell, Exploration of the Colorado River of the West, Washington, 1875 (out of print ; second-hand stores) ; Powell, Canyons of the Colorado, Flood and Vincent, Meadville, Pa., 1895, $10.00 ; Dutton, Colorado Canyon, 2d Annual U. S. Geological Survey, p. 49 ; also Monograph II, U. S. Geological Survey, Washington, D.C., $10.00. MOUNTAINS. 64. Introductory. — Mountains contrast strikingly with plains, but resemble dissected plateaus in irregularity of form. The ruggedness and coldness of lofty mountains make them barriers rather than attractive homes. Mineral wealth often induces men to live among mountains, and, in summer, people are attracted to them by the cool climate and beautiful scenery. But, not being suited to extensive agriculture, mountains are never densely settled. These and other facts furnish reasons why mountains are worthy of study. There are many questions o-f interest which such a study will answer. Why, for example, are the Alps so high and rugged, the Appalachians so low and ridge-like, and the New England mountains so low and hilly ? Why do rivers sometimes cross mountains in narrow gaps while other mountain valleys are broad and flat-bottomed ? The following pages answer tains are almost never horizontal. All kinds of folds and faults (p. 37) are found. Some mountains, like many in the Great Basin, are simply faulted and tilted blocks of strata, with the layers inclined in a single direction (Fig. 155). Others, like the Jura in Switzerland, consist of strata folded into regular anticlines and synclines (Fig. 168). Still others, like the Alps, are very complexly folded and faulted (Fig. 156). The strata of the Appalachians were originally horizontal, ward, as they would extend if nothing had heen removed. but are now complexly folded. If they could be straightened out to their original condition, they would occupy fully six times as much area as now. That is to say, 120 miles of rock strata have, by folding, been crowded into twenty miles of mountain. Such complex folding often so alters, or metamorphoses, the rocks that it is very difficult to tell their original condition (p. 34). Igneous rocks often cut across the mountain strata (Fig. 34), and, therefore, one may in a short distance find many kinds of rock — granite, gneiss, sandstone, limestone, etc. — occupying many different positions. This complexity gives denudation an opportunity to sculpture mountains into many irregular land forms that are not possible on plains and plateaus. Summary. — ^fountain rocks are inclined at various angles bf/ folding and faulting, and they are cdso very complex in kind. In these respects mountains coyitrast strikingly tvith plains and plateaus. 66. Names applied to Parts of Mountains. — A mountain system is a series of mountain folds, raised by the same uplift and forming a single group. A mountain system consists of minor portions, or ranges (Fig. 153). — Diagram to show mountain ridges where denudation has etched inclined hard strata into relief. called a cordillera. For example, the Cordillera of w-stern United States includes four systems, — the Coast Ranges, the Sierra Nevada-Cascade system, the Basin Range system, -and the Rocky Mountain system. Each of these systems consists of a number of ranges; for instance, the Rocky Mountain system has many ranges, such as the Wasatch and Uinta ranges. There are different kinds of valleys among mountains. The largest of these are the broad plateaus between mountain systems. When they have no outlet to the sea, as in the Great Basin of the West, they are called interior basins (p. 22). Smaller basins without outlet are formed between mountain ranges by downfolding. Broad valleys in the Rocky Mountains, some due to folding, others to denudation, are commonly called parks (Fig. 165). In the Appalachians, narrow gorges cut by streams across ridges, are called water gaps (Figs. 172, 463, 467). A mountain pass (Figs. 158, 187) is a low portion of a mountain divide. Passes are usually caused by denudation, where streams head together on opposite sides of a divide. Their position is often due to the presence of a weak rock. Summary. — The names cordillera, system, range, ridge, and j^eak are applied to mountains or parts of mountains. The names interior basin, j^ark, water gap, and pass are applied to mountain valleys. Therefore, high plateaus and mountains rise into the cool upper layer^i if the air. Indeed, many mountains rise so high that there is perpetual snow on their summits, and glaciers in their valleys. The line above which there is perpetual snow is calJed the snow line (Figs. 153, 157). Below this is a belt with a climate too cold for tree growth. The line above which trees cannot grow is known as the timber line (Figs. 158, 166). These lines are lower on the shady than on the sunny side of mountains, and in the temperate than in the tropical zone. Mountains in the path of vnpor-bearing winds have abundant rainfall on the slopes against which the winds blow (p. 287). The opposite slopes, and the country beyond, are dry, because so much vapor is lost in passing over the mountains. This is well illustrated in northwestern United States, where winds from the Pacific cause abundant rain on the western slopes, but reach the eastern side so dry that the country is arid. Summary. — On higJi mountains there is a line, called the timber line, above which no trees can grow; higher still is a zone of perpetual snow. Mountains are well watered on the side from ivhich vapor-bearing icinds blow, and often arid on the opposite slopes. 68. Denudation of Mountains. — The climate and great elevation of mountains give high power to the agents of denudation. Because the rivers are well above base level, they are able to cut deep gorges (Fig. 167) and canyons. Weathering is also very active, especially on steep slopes above the timber line (Figs. 51, 160), where there is little vegetation to offer protection to soil and rock. In such situations the' rock is exposed to sharp contrasts in temperature between day and night ; frost action is vigorous ; and the strong winds, heavy rains, and melting snows all help to move rock fragments down the steep slopes'. than can be thus removed. In time this forms a mantle of rock waste, or talus (Figs. 66, 160), which covers the lower slopes, and, by its smooth, curving outline, frrms a striking contrast to the rugged, irregular slopes above. As the talus grows, its slope becomes more gentle, till rocks no longer roll down over it. Then the decay of the fragments forms a soil in which trees may grow and on which farms may be located. Where wet weather streams descend the mountain sides, these talus slopes grade into steep alluvial fans and debris cones (Figs. 109, 160). At all times small fragments of rock are falling from the steep mountain slopes ; but, in addition, there is an occasional fall of large masses, forming an avalanche (Fig. 161) or a landslide. In an avalanche thousands, and sometimes millions, of tons of rock, mingled perhaps with ice, come tearing down the mountain side, destroying everything in their course. Rivers are dammed, villages destroyed, and roads ruined. In the spring of 1901 an avalanche of rock and ice from an Alpine vf^lley descended across the road which Napoleon built over the Simplon Pass (Fig. 162). It ruined a mile or two of the road and utterly destroyed a mountain village. About a century before, a similar avalanche occurred in the same place. Mountains supply many instances of such destructive landslides. They are usually started by frost, or by the effect of rain or melted snow, which saturates the soil or rock, making it so heavy that it can no longer stand in its position. As a result of rapid denudation, acting on the complex rocks» mountains are cut into a great variety of rugged forms, — peaks, ridges, precipices, gorges, and passes. There are peaks almost impossible to scale, some so steep and sharp-pointed that they are called ' needles" and "horns"' (Fig. 157); there are ridges that no roads cross ; and, in fact, a surface often so rugged that large areas are uninhabited. Summary. — River erosion and tveatheriiig are very active among mountains, especially above the timber line. Mock fragments, falling from steep slopes, accumidate at their base as talus, debris cones, and alluvial fans; and occasioncdly larger masses descend as avalanches, By this rapid denudation high mountains are made very rugged. 69. Resemblance between Mountains and High Plateaus. — Some plateaus are more elevated than many high mountain peaks ; it is only very lofty mountains that rise higher than 10,000 feet, and yet there are plateaus which reach that level. These high plateaus are often so carved by vigorous denudation as to closely resemble mountains (Fig. 146). They are, in fact, sometimes called mountains. The Catskill Mountains, for example, are not mountains in the true sense, but dissected plateaus. In the Catskills, denudation has carved out peaks and deep valleys with precipitous sides; but the nearly horizontal strata prove that they were uplifted as Summary. — Vigorous denudation so scidptures high lolateaus, like the Catskills, as to make them resemble mountains in ruggedness ; hut their strata are horizontal. 70. Distribution of Mountains. — Although mountains are typical of continents, there are ranges in the open ocean ; for example, the New Zealand and Hawaiian islands. The latter are volcanoes rising from the crest of a submarine mountain fold, having a length of 1500 miles. There are many other ranges in the ocean, especially in the Soutli Pacific. Mountains are common at or near the border of continents (Figs. 20-27). They sometimes fringe the coast, as in the case of the Kurile, Japanese, and Philippine islands, and the East and West Indies. Mountain chains also extend from the land into the sea, forming peninsulas ; for example, the peninsulas of Lower California, Kamchatka, Malay, Greece, and Italy. In other places mountain systems form the very border of the continents, rising directly out of the sea. Such a condition America and the Andes of South America. Mountains are also found far from the coast; for example, the Appalachians, Rocky Mountains, Sierra Nevada, and the mountains of central Europe and Asia. But most mountains of the interior, when first formed, rose from the sea. A large number of the mountain systems extend from north to south (Figs. 20-25). It is to this fact that several of the continents owe their shape, — that of a triangle, with the long direction from north to south (p. 23). There are, however, many ranges running east and west, especially in Asia and Europe (Figs. 26, 27). No regular law has thus far been discovered regarding the distribution of mountains. Summary. — Mountains occur on continents, both in the interior and along the border, where they fonn chains of islands, peninsulas^ and systems ivhich rise at the very margin of the land. They also form island chains in the open ocean. Some extend north and south, others east and west. 71. Cause of Mountains. — The explanation of mountains most widely accepted is that of contraction (p. 20). As the heated interior of the earth cools and shrinks, the cold crust settles; but it cannot fit the constantly shrinking interior without wrinkling. This causes mountains, which are wrinkles in the earth's crust. You can illustrate this by covering a ball with a thick flannel cover a little too large for the ball, then trying to press it down on the ball. Some parts of the cloth must wrinkle. There is evidence that mountain folding has occurred again and again in the same place ; also that this growth has been slow. Several times, mountain systems have risen in eastern and western United States ; but, in the plains between, there has been practically no mountain formation at any period. The same is true of other parts of the earth. Summary. — Mountains are wrinkles of the earth's crust, caused by its settling on the cooling and contracting interior. They have been formed slowly and by successive uplifts. 72. Types of Mountains. — Perhaps the simplest type of mountain is that in which a block of strata has been uplifted, along a fault plane, and tilted (Fig. 155). Such a mountain has one moderate and one steep slope, while the crest is a ridge parallel to the fault plane. Mountains of this type are found in southern Oregon and other parts of the Great Basin. These tilted block mountains may reach a height of 4000 or 5000 feet, a width of 10 to 20 miles, and a length of 50 to 100 miles. such a mountain there is no ridge, but a central area from which the surface slopes in all directions. This type is illustrated by the Henry Mts. (Fig. 164) and others in the West. A third simple type is the evenly folded mountain, illustrated by the Swiss Jura (Fig. 168) and parts of the Appalachians. When such mountains are formed the surface is thrown into a series of regular waves, like the waves of the sea, the anticlines forming mountain ridges, the synclines, valleys Fig. 167. — A deep, narrow gorge in the Ali)S. Tliere are pot holes jusi above the path on the left, showing that the stream bottom was once at that level. This gorge is being rapidly deepened. (Fig. 168). When denudation cuts deeply into these, as in the Appalachians, each hard layer is left as a ridge (Fig. 172). Mountains whose strata are greatly contorted (Fig. 156) and metamorphosed, with much igneous rock, have a far less simple form. De- rugged forms. 73. Life History of Mountains. — Let us assume that the strata of a plain are being folded to form a mountain system. As the strata slowly bend, the surface becomes irregular ; and, when the .strain becomes too great, the rocks slip along fault planes. This jars the earth, forming earthquake shocks, which may Vie very severe. Through the deeper fissures, lava may rise, building volcanic cones. Such earthquakes and volcanoes are common in regions of grcwing mountains (pp. 125, 132). From the very first the rising land is attacked by J:be agents of denudation ; but this attack increases as the mountains grow higher. Since the mountains are not worn dowo as rapidly as they are elevated, they continue to grow higher, reaching above the timber line and even into the zone of perpetual snow. Then glaciers extend down the valleys. Down-folding forms broad valleys between the ridges ; and streams cut narrow gorges across them. Tlie durable rocks are etched out into ridges and peaks, the weak rocks are cut away, forming valleys and passes. In this stage the surface is so irregular that few people are able to live among the mountains. Such mountains, illustrated by those of western North and South America, the Himalayas, and the Alps, are young mountains. Find pictures of young mountains in this chapter. The time comes when uplift ceases : but denudation continues to broaden the valleys and lower the peaks and ridges. As the mountains are lowered, glaciers disappear, and, in time, even the highest peaks may come below the timber line. Such mountains, which have lost the ruggedness of youth, may be called mature ; the Appalachians and the mountains of New England, Norway, and Scotland, are examples (Figs. 170, 172, 188, 189, 192, 193, 455). Their slopes are forested, their valleys tilled. Further lowering may continue until the mountains are reduced to a series of low, rolling hills ; or, further still, to a surface almost as level as a plain. Such a surface is known as a peneplain (almost plain) (Fig. 171). The mountains are then old^ and are, like plains, adapted to dense settlement. New York City, Philadelphia, Baltimore, and Washington are situated on such old, worn-down mountains. These ancient mountains, known as the Piedmont belt, extend from New England to Alabama, east of the Appalachians. After being worn to low relief, a mountain region may be reelevated, and caused to start on a new life history, as has been the case with the Appalachians. Then denudation may etch the ridges of hard rock into relief again, and form broad valleys where the strata are weak (Figs. 172, 173, 192, 193). The broad made famous by the poet Wordsworth. The lake is Derwentwatet Fig. 171. — The upland, or •"penopluiu," of iNew ±!:iiglana ; a worn-down mountain region, uplifted again so that the streams have had new power given them (rejuvenated). This has enabled the streams to sink their valleys into the " peneplain." Fig. \1'A. — To illustrate the origin of the Appalachian ridges. The mountains were worn down to low relief, as in the left-hand figure ; then, after uplift, the ridges were etched out. The streams crossing them have cut water gaps, while broad valleys have been developed between the ridges in the weaker strata. Fig. 174. — The left-hand figure shows two anticlinal ridges each cut into for a short distance by a stream. As the streams cut deeper and grow longer, they reach below a hard layer (the darkest one in the diagram), which, because of its hardness, is left standing as a ridge on each side of the valley (right-hand figure). The law of monoclinal shifting will cause these ridges to retreat away from the stream, thus broadening the valleys in the anticlines, and at the same time narrowing the synclinal valleys. (See also Fig. 179.) Fig. 175. — In the left-hand figure a stream heads on a divide and flows in a short course toward the right to the sea. This steep slope gives it power to gradually eat backward until it reaches a stream having a long, roundabout course to the sea. It then captures the stream and leads it out to the sea by the shorter course, as shown in the right-hand fij.'-ure. valleys are well settled (Fig. 466), but the ridges are too rough and rocky for farming, and are often timber-covered (Figs. 85, 467). Where streams leave the broad valleys to cross the ridges of hard rock, they flow in narrow gorges, or ivater gaps (Figs. 178, 463, 467), because there has not been time for weathering to broaden valleys in so hard strata. Summary. — As mountains rise, the effect of denudation increases, and young mountains are therefore made very rugged. Mature mountains have been lowered and the valleys broadened; and. old mountains are still further lowered, and perhaps even reduced to 1 peneplain. Uplift alloivs denudation to again etch the hard strata into relief. 74. The Drainage of Mountains. — In early stages, in consequence of the slopes, numerous short streams flow down the mountain sides in gorges ; and longer streams follow the broad valleys between the mountain folds. Here and there the main streams cut deep gorges across low points in the folds (Fig. 168). In such consequent mountain drainage there are, at first, numerous lakes held up by the mountain iams. These, however, are soon filled with sediment brought oy tne mountain torrents. A slight renewal of mountain movement may warp the valleys and form new lake basins (Fig. 296). Some of the Alpine lakes, such as Geneva, are thus explained. If the elevation of the land ceases, the valleys pass through the stages of youth, maturity, and old age. But the great elevation, and the hard and complex nature of the mountain rocks, make the life history of a river valley in mountains longer than in plains and in most plateaus. The wearing away of the weak rocks leaves the hard strata standing as divides (Figs. 38, 154, 169). As the surface slowly wears down, the divides still remain on the more durable strata. These mountain strata usually incline, or dip ; and, as they are slowly worn away, their crests, that is the divides, not only become lower, but shift to one side (Fig. 176). This, called the law of monoelinal shifting^ may be stated as follows : As denudation lowers a region of inclined strata^ the divide migrates in the direction of the dip. may have more power than another : one may have more rainfall ; or it may have a shorter and steeper slope ; or it may have only weak strata to remove while its opponent struggles with hard strata. There are nmnerous illustrations of such migration of divides. In the Catskills, for example, the streams descending the steep eastern slope to the Hudson have pushed the divide backward and captured the headwaters of streams that have a long, gentle slope (Fig. 177). The Appalachian rivers, — the Potomac, Susquehanna, Delaware, etc., — which cross ridge after ridge (Figs. 172, 192), are believed to have slowly eaten their way across the mountains by headwater erosion and river capture. Wind gaps of the Appalachians are also caused by river capture (Fig. 178). tain sides, along the valleys of folding and across the ridges. They Fig. 176. — To illustrate the migration of divides. A hard layer A forms a divide ridge. When the surface has heen worn down to the line CO (upper figure) the ridge A will have migrated to the right, as shown in the lower figure. See also Figs. 174, 179. Fig. 177. — The headwaters of a tributary (left-hand figure) rise on a highland and flow a long distance, in a roundabout course, to reach the main stream. Two short streams head in the same region, but flow in steep courses to the main stream. This gives them power to eat back at the divide and rob the long tributary of some of its headwaters (right-hand figure). This condition is somewhat like that in the Catskills. Note that the tributaries of the captured streams join in barb fashion. Pig. 178. — In the left-hand figure two streams cross a mountain ridge of hard rock. A tributary of the upper one heads back nearly to the point where the lower one turns to cross the ridge. For some reason (perhaps greater volume) the upper stream has more power to cut into the ridge, thus deepening its valley. This gives to its tributary a slope which permits it to gradually eat backward until it taps the lower stream, drawing it off through the upper water gap. This leaves a wind gap where the lower stream formerly crossed the ridge (right-hand figure) . Fig. 179. — The process of raonoclinal shifting, illustrated in Figs. 174 and 176, is carried farther in this diagram. In the upper diagram there are four streams, A, B, C, and D ; A and C in small valleys in the anticlines, B and D in broad synclinal valleys caused by down folding. They are consequent on the mountain form. In the middle figure there is little change, excepting that the anticlinal valleys have been lengthened and deepened, this being possible because they are so high that the streams have much power, while the synclinal streams are held back in their work by lakes (not shown here) and hard strata. The lower figure represents a much later stage, in which the surface has been greatly worn down. Monoclinal shifting has pushed the divides away from the anticlinal streams (Fig. 174), therefore broadening their valleys and narrowing the synclinal valleys. This has robbed the synclinal streams of water, and consequently weakened them, while it has increased the power of the anticlinal streams. As a result, the conditions have been reversed from the first stage, and the anticlinal streams, A and C, flow in broad, deep valleys, while the synclinal streams are in high, narrow valleys, on the tops of synclinal mountains. Instances of this change are found in the ADoalachiaus. Fig. 180. — The lower slopes of the Alps along the deep valley occupied by Lake Como. These slopes are cultivated, growing olives and grapes, and towns cling to the mountain base wherever there is enough level land, especially .on the stream deltas (Fig?. 107, 297). are likely to be interrupted by lakes. Slowly they pass through youth, maturity, and old age, unless interrupted by renewed mountain growth. TJie divides change position by the law of monoclinal shifting, and by headwater ei'osion. In the latter case the more favorably situated streams capture the headwaters of opponent streams. 75. Settlement of Mountains. — The soil and climate of mountains are usually unfavorable to agriculture, and, in many cases, absolutely forbid it. Large areas are even unfit for the growth of forests. For these reasons mountains are usually sparsely settled (Figs. 157, 158, 183, 185). The relation of mountains to settlement is well illustrated by the Alps, which rise in the midst of a densely populated land, — Italy on the one hand, France and Germany on the other. If we were to cross the Alps from the Italian side, this is what we should see : first a level plain, the Po valley, dotted with farms and villages, and densely settled. As the land becomes irregular in the foothills, there are fewer people ; and, when the mountains are reached, large areas are found with a surface too rocky for cultivation (Figs. 107, 180). Wherever there is soil enough, however, vineyards and groves of olive and mulberry trees are seen on the valley sides. Higher up, where the climate is cooler, the olive, mulberry, and grapes no longer grow (Figs. 153, 182). There small grain-fields and pasture lands are interspersed with rocky cliffs and forested areas, in which the chestnut is a common tree. Still higher, where the climate is that of the cold temperate zone (Fig. 109), evergreen trees prevail, and only the hardiest grains can be raised. Most of the land that has soil enough is used as pasture, and cows and goats are raised in large numbers. Between the timber line and the snow line there is an area on which no crops can be raised, but where the pastures support herds of cows and goats for a month or two in summer (Fig. 181). Above this is a wild, dreary mass of snow, rock, and ice, where no one can find sustenance (Figs. 157, 182, 183). Summary. — Mountains are sparsely settled. Agriculture may flourish at the base, hut the ai^ea suitable to cultivation becomes S7naller the higher one goes, and the climate more and more unfavorable, until, at the snow line, a barren area of snoiv and rock is reached in which there are no inhabitants. 76. Mountains as Barriers. — Mountains are barriers to the passage of animals, plants, and men. On a plain, animals and plants spread freely ; but the ruggedness and coldness of mountains check, and in many cases prohibit, the passage of animals and the spread of plants. Even the passes of high mountains, like the Alps, have deep snow until summer. The low Appalachians served as a barrier to the westward spread of the early colonists (p. 308). The Alps (p. 388) have always been an obstacle to man, being crossed only with difficulty and along the few passes. The Himalayas (p. 388) are an even more effective barrier ; and the Pyrenees are covered and protected by avalanche sheds. Railways cross even the lofty Rocky Mountains (Fig. 471), Andes (Fig. 184), and Alps (Fig: 186). They pass up the valleys as far as they can (Figs. 57, QQ>), curving about, first on one side, then on the other ; crossing deep gorges by lofty bridges ; tunneling the rock, even by curved tunnels ; and finally, when it is no longer possible to climb higher, plunging through a great tunnel into the very heart of the mountain. The St. Gothard tunnel is nine and one fourth miles long; the Simplon tunnel, farther west, is even longer. Summary. — Tlie ruggedness and coldness of mountains make them harriers to the spread ofjylants, animals, and man. Now, Giving to the building of roads and railways, mountaiyis are far less important harriers than formerly, 77. Mountains as Summer Resorts. ^ — The cool summer climate and the wild and beautiful scenery attract many people to mountains. The numerous mountain lakes which offer opportunities for boating and fishing, and the hunting on the forest-covered mountain slopes, are further attractions. The mountains of New England (Fig. 189), the Adirondacks (Fig. 188) and Catskills of New York, and the Appalachians are visited each year by large numbers of people. But in winter they are cold, snow-covered, and nearly deserted. The Alps, the wildest and most beautiful of European mountains, have come to be the greatest summer resort in the world. In the small country of Switzerland, which is only one third the size of Pennsylvania, there are thousands of summer hotels. At every point where many tourists are likely to go, even on mountain trails far from wagon roads, a hotel is sure to be found (Figs. 169, 183, 187). In the height of the season most of these hotels are full to overflowing with tourists from all parts of Europe, in fact, from all the world. One of the leading industries of Switzerland is the entertainment and care of these visitors. remains (Figs. 85, 188, 189). About one fifth of the surface of Norway is forest-covered, and much of the remainder is either too higli or too rocky for trees to grow. The mountains of eastern and western United States still have great timber resources and are the seats of important lumber industries. agriculture has not demanded the removal of the forests, 79. Mineral Wealth of Mountains. — The Alps have little valuable mineral; but the mountains of eastern and western United States, and many other lands, are very rich in mineral. In the West, gold, silver, lead, and copper are most important; but zinc, iron, coal, and building stones are also found. In the mountains of eastern United States, coal, iron, and building stones are the leading mineral products. The presence of metal has attracted many people to mountain regions, where otherwise there would be only a sparse population of farmers, herders, hunters, and lumbermen. In rugged mountain valleys, and tain rocks (Fig. 191). Sometimes they are preserved from erosion by being folded down in the synclines, as in the case of the anthracite coal of Pennsylvania (Fig. 194). This was formed at the eame time as the bituminous coal that is found west of the Appalachians ; but, during the folding of these mountains, the pressure Fig. 192. — Topographic map of Appalachian ridges where crossed by the Susquehanna above Harrisburg, showing the broad valleys and the narrow, Bteep-sided water gaps. See Figs. 172 and 173. ^Harrisburg Sheet, U. S. Bteoloffical Survey Topographic Map-'i metamorphosed it to " hard " or anthracite coal. At Scranton, Wilkes Barre, and elsewhere, the anthracite is now being removed from the synclines in which it has been so long preserved. been folded down in a syncline, and thus preserved from erosion. Summary. — Many mountains contain valuable mineral dejmsits^ which attract settlers. Folding and erosion help to reveal these deposits ; and soynetimes they are preserved in the synclines. 68. Denudation of Mountains. — (a) Kiver erosion, (h) Weathering : reasons for activity, (c) Talus : cause ; form produced ; change to farm land ; debris cones, (d) Avalanches : size ; effects ; Simplon avalanche ; cause, (e) Effect of denudation on land form. 73. Life History of Mountains. — (a) Young mountains : early growth ; earthquakes; volcanoes; increasing denudation; valleys; unfitness for occupation; examples. (&) Mature mountains: broadening; lowering; examples ; fitness for occupation, (c) Old mountains : further reduc- 74. The Drainage of Mountains. — («) Consequent drainage : stream courses; lakes. (6) Life history — compare with plains, (c) Monoclinal shifting : nature of process ; law. (cQ River pirates : battle at headwaters; favoring conditions ; Catskills; Appalachians; wind gaps. 68. Why are rivers and weathering very active in mountains? What becomes of the fragments that fall? What are the nature, effects, and causes of avalanches ? What effect has denudation on mountains ? 73. What happens when a mountain is rising? What effect has denudation? What are the characteristics of young mountains? Trace the development through maturity to old age. Give illustrations of each. What is a peneplain ? What has been the history of the Piedmont Belt? What changes have occurred in the Appalachians ? 74. Describe the consequent drainage of mountains. What is the normal life history? What causes lakes? How does the law of monoclinal shifting operate ? What are river pirates ? Why do they succeed? Give illustrations. Explain wind gaps (Fig. 178). Suggestions. — (1) Slowly dry an apple. Notice how the skin wrinkles as the inside grows smaller through the evaporation of the water. Compare this with what is happening in the earth. (2) Find out how the tire of a wagon wheel is put on, and why it fits so tight. (3) Get a metal rod, and have a thick metal ring made just too small to fit over it. Heat the ring red-hot and see if it goes over the rod. Have another ring made to fit the rod exactly. Heat the rod and see if the ring will go over it. What does this show ? (4) See suggestion for covering a ball, given on page 99. (5) It is not very difficult to make an apparatus for imitating the folding of rocks. Of one-inch boards make a long, narrow box, say 2 feet long, 5 inches wide, and 8 inches deep, open at one end and the top. Place four or five thin layers of wax, differently colored, on the bottom. At the open end apply slow, steady pressure, best obtained by using a screw, like that which sets a vise, fastened to a board that just fits into the end of the box. Before applying the pressure, place over the wax layers enough of shot to nearly fill the box. After pushing the layers a few inches, remove the shot, unscrew one side, and the layers will show folding. A simpler experiment may be made by taking a series of pieces of thick cloth and felt, cutting them to the same size, and pressing them up with the hand. (6) Is your home among mountains, or have you ever been among mountains? What is the nature and position of the rocks? Do the mountains rise above the timber line? Are they young, mature, or old ? Are they well settled ? Why ? Are there forests ? Mineral ? Are they resorted to in summer? Why? Reference Books. — King, Mountaineering in the Sierra Nevaday Scribner's Sons, New York, 1902, ^1.50 ; Lubbock, Scenery of Stcitzerlajidy Macmillan Co., New York, 1896, \|1.50; Russell, Southern Oregon, 4th Annual U. S. Geological Survey, p. 435 ; Tarr, Physical Geography of Neio York ^Sfa/e, Chapter III, Macmillan Co., New York, 1902, $3.50; Hayes, Physiography of the Chattanooga District, Part II, 19th Annual U. S. Geological Survey, p. 9; Willis, The Northern' Appalachians, National Geographic Monographs, American Book Co., New York, 1895, $2.50; Hayes, The Southern Appalachians, same; Willis, Mechanics of Appalachian Structure, Part II, 13th Annual U. S. Geological Survey, p. 217. VOLCANOES. 80. Graham Island. — South of Sicily, in 1831, a new volcano was born. During the eruption large volumes of steam rose into the air, carrying up fragments of lava. The expansion of the steam in the melted rock caused numerous cavities, and broke the lava into bits of porous ash and pumice. Some of the lightest ash drifted away in the wind ; much of the pumice was light enough to float on the water ; but many of the heavier fragments fell back near the outlet, building a cone which rose 200 feet above the sea and had a circumference of almost three miles. With this single eruption the life of the volcano seems to have ended ; and soon the waves cut the loose ash cone away, leaving a shoal ' to mark its site. Other volcanoes, some in the sea, some on the land, have become extinct after a single gasp ; but most volcanoes have a longer and more varied life. From some, ash is always erupted ; from others, streams of liquid lava ; and from many, now ash, now lava. Some erupt freely and at frequent intervals ; others have violent outbreaks, following long periods of quiet. These differences between volcanoes may best be" illustrated by studying a few typical ones. Summary. — Graham Island became extinct after a single enqMon of ash and immice, formed by the bloiving up of melted rock by in^ duded steam. Other volcanoes have a much more varied history, VOLCANOES, EARTHQUAKES, AND GEYSERS, 113 81. Stromboli. — Between Sicily and Vesuvius, in the Lipari Islands, is the ever active volcano Stromboli. It is a small cone, about 6000 feet from bottom to top, half its height being above sea level. Steam rises from a crater on one side of the cone, and the steam clouds glow with light from the melted lava, which always stands in the crater. Every few minutes the steam erupts masses of lava; and sometimes there is a mild eruption which throws May, 1902, the beautiful city of St. Pierre, in Martinique, was wiped out of existence by a terrible volcanic eruption from Mont Pel6 (Fig. 197). Between 25,000 and 30,000 people were killed in a few seconds, and only one person in St. Pierre, a prisoner in the jail, escaped death. On the previous day there was a destructive eruption from the volcano of La Soufriere, in the neighboring island of St. Vincent. The last previous eruption of Mont Pele was in 1851 ; in 1812 there was a terrific and destructive eruption of La Soufriere. The people of St. Pierre had almost forgotten that danger lurked in the slumbering volcano ; and, though the outbreak of 1902 was preceded by distinct warnings, few heeded them. On April 25 warm water was reported in the old crater ; later, dust-laden steam rose from it ; then a lake rose, overflowing the crater rim on May 5, and sending a deluge of hot water and mud down a valley. ments and gases, rushed with the violence of a tornado, destroying everything in its path. It overturned trees and lionses, and even carried a hollow iron statue, 11 feet high, a distance of 50 feet. Most of the deaths were probably caused by breathing the steam and hot ashes. Fig. 199. — Vesuvius from Poujpeii, whose ruius are now largely excaviu The remnant of Monte Somma forms the ridge on the right, while the pre ent cone of Vesuvius rises in the middle. There have been several later outbursts, all, like the first, erupting ash, with no flowing lava and with no destructive earthquake shocks. The eruptions have built a cone 1500 to 2000 feet high in the old crater, and the ash has fallen over the whole island (Fig. 198) and the sea round about. After the eruption of June 6, a quarter of an inch of ash fell upon a ship over 100 miles from the volcano. At a distance from the volcano the ash deposit is thin ; but on and near the cone it is several feet deep, resembling freshly fallen snow. During each eruption the condensed steam causes heavy rains, which wash vast quantities of loose ash down the steep slopes in destructive mud flows. Sometime — no one can foretell when — the eruptions will cease, probably to break out again when energy enough has accumulated. Summary. — In May, 1902, after a long period of quiet, Mont Pele and La Soufrih^e hurst forth in eruptions of ash, causing much destruction. There have been numerous eruptions since then, and vast quantities of volcanic ash have been thrown out upon the islands and the sea round about. The condensed steam, forming rain, has ivashed much ash down the volcano side, coMsing mud flows. and cities were located at its base. In the year 79 it broke forth in a terrible eruption which buried the farms and villages beneath ash, and destroyed Pompeii and Herculaneum, Fig. 201. — The form of Vesuvius, or Monte Somma, before 79, according to Strabo. Only a part of the crater rim now stands (Fig. 199), the present cone rising on the site of that part of the crater nearest us. Before the eruption there were frequent earthquakes, one v^r which partly destroyed Pompeii ; and, finally, a terrific explosion occurred by which half the crater wall was blown away. The ashes rose thousands of feet in the air, settling on all the country round about. The naturalist Pliny, admiral of the Eoman fleet, who was at Misenum (near C. Miseno, Fig. 202), started toward the mountain and lost his life. Letters of Pliny's nephew to the historian Tacitus, telling of the death of his uncle, are the only description of the eruption that we have. Pozzuoli to Ischia. The day was changed to the darkness of night by a heavy cloud of ash ; hot ashes and stones fell all about ; the air was filled with sulphurous gases ; the ground was violently shaken ; there was fierce thunder and lightning; and the cries of terror from the people, who rushed madly about, added to the din. Thousands of people were undoubtedly killed, though there is no record of the number, nor even of the villages destroyed. Fro. 206. — A view into the crater ol Vesuvius. This photograph was taken during the above eruption, when the lava was drawn out of the crater. At ordinary times tb* crater is se illed with steam that one cannot look f»r dawn into it iriG. 207. — Monte Xuovo, a small ash cone, at the head of the Gulf of Pozzuoli (Fig. 202), which was thrown up during an eruption in 1538. It has not erupted since, B,nd its slojies are now cultivated. Fig. 208. — The crater of another volcano at Pozzuoli, aJso extinct. Steam and sulphurous gases, forming sulphur crystals, still rise in this crater, and vegetation is unable to grow where tb^y lise. excavated (Fig. 199). From these excavations we learn what the life of the Romans was on the day of that fearful outbreak nearly 1900 years ago. The houses had been so well preserved beneath che ash that even pictures painted on the walls are still quite perfect. It is a wonderful experience to walk through those deserted streets (Fig. 200), and to see how the people lived, and what they did, as if they had left but yesterday. Yet it is a picture of life almost at the time of Christ. Since 79 Vesuvius has had many eruptions, some violent, some moderate (Fig. 205), some of ash, some of lava (Fig. 203). The remnant of old Monte Somma still stands on one side of the present cone, which rises 4200 feet above the level of the Bay of Naples (Fig. 202). At most times visitors may go to the YQTj edge of the crater (Fig. 206). Standing on the side from which the wind blows, one looks down into a deep hole, out of which vast quantities of steam rise with a roar, bearing sulphurous gases. Every few seconds there is a slight explosion, when masses of red-hot lava are thrown up, often higher than the crater wall. At night the lava in the crater causes a glow on the cloud that overhangs Vesuvius. Occasionally the volcano grows more active ; then hot stones rise so high that they fall on the crater edge, and it is unsafe to stand there. This may increase until the stones fall some distance beyond the crater. The small cinder cone that surrounds the crater is made of these loose fragments. Now and then lava issues from the cone, flowing in a great stream, sometimes clear to the sea. The recent flows form great black, rugged scars on the volcano side (Fig. 204); the older ones are partly decayed and covered v/ith a soil. There is an observatory on the slope of Vesuvius in which scientists study the volcano and attempt to predict eruptions, Vesuvius is only one of several volcanic cones in the Bay of Naples (Figs. 207, 208). The famous lake Avernus is in a volcanic crater ; the island of Ischia is a volcano (Fig. 202) ; and there are several others in the same region. All of them have been long extinct, though hot water, steam, and gases still rise in some places. There are numerous proofs that changes in level of the land have accompanied the volcanic activity of this region (Fig. 37). Summary. — In the year I'd, after being long dormant, Vesuvius hroJce forth in violent eruption, jyttrtially destroying the cone and burying Pompeii and Herculaneuni, lohich have been ivell preserved beneath the volcanic deposits. Since then Vesuvius has had many eruptions of ash and lava, some of them very violent. Ordinarily it is so quiet that one may go to the very edge of the crater, from ivhich steam constantly rises, bearing upward masses of lava. In the neighborhood there are extinct volcanoes. 84. Etna. — The greatest volcano in the Mediterranean is Etna, on the eastern end of Sicily. Steam rises from its crater (Fig. 209), and every few years there is an eruption. Then lava issues from fissures in the mountain side and flowc in enormous masses down the slopes, even to the sea, often destroying villages on the way. There are scores of small cones, 200 to 300 feet high, built along these fissures (Figs. 209, 210). Etna rises 10,870 feet above the sea, and at its base has a circumference of over 60 miles. It is so high that, although oranges and bananas grow at its base, the climate at the top is frigid. This great cone is made entirely of lava and ash forced out from within the earth by steam. The recent lava flows, those only a few score years old, are barren masses of black rock too rough to cross. But this lava decays so readily, and forms so fertile a soil, that in a century, portions of a flow are fit for cultivation. Soil is often gathered in baskets and placed between the lava blocks for the planting of grapevines. Summary. — The huge cone of Etna is inade of lava, issuing mainly as great flows from fissures in its flanks. Tliis lava decays quickly, forming a fertile soil. 85. Krakatoa. — For a century the small volcanic island of Krakatoa, near Java, in the Straits of Sunda, was dormant. In August, 1883, it broke forth in the most terrific eruption that civilized man has known. A large part of the cone, together with ash from below, was hurled high into the air, and the site of the destroyed cone was occupied by water 1000 feet deep (Fig. 220). Every vestige of life on the island was destroyed, and its surface was deeply covered with ash. For miles around, the sea was so thickly covered with pumice that the movement of vessels was interfered with. The finer ash was thrown so high into the air that it was carried all round the earth, causing brilliant sunsets in Asia, Europe, and America. So violent was the explosion that a great air wave was started which passed three times around the earth. Windows were broken 100 miles from the volcano, and the sound of the explosion was heard more than 150 miles away. A water wave was also caused which spread all over the Pacific, being measured on the coasts of Africa, Australia, and California. Xear the volcano this wave washed over the land to a height of 50 to 100 feet, killing 35,000 people. Since then Krakatoa has been quiet. It may have become extinct; but more probably it is only dormant, and will again burst forth when the pent-up steam once more gathers sufficient energy to force its way to the surface. Summary. — After a century of quiet, Krakatoa burst forth, in 1883, in the most violent eruption known. Half the cone ivas bloivn away ; ash fell all about, and was carried far ayid wide by the ivinds; a great air wave passed three times round the earth; and a water luave spread over the Pacific. Since then the volcano has been quiet. 86. Hawaiian Volcanoes. — There are numerous volcanic cones in the Hawaiian Islands (Fig. 221), most of them extinct. The two highest are Mauna Loa and Mauna Kea, which, with the smaller Kilauea, are on the island of Hawaii (Fig. 211). This island, the greatest volcanic mountain in fore the lava rises high enough to flow out over the rim of the crater, its weight and the steam pressure usually open a fissure in the mountain side through which the lava is drained (Fig. 211). This occurs, on the average, once in about seven years, and no violent ash eruptions have ever been recorded. The fissures are usually formed above sea level, but sometimes occur beneath the sea. Some of the lava streams are 30 or 40 miles long and 2 or 3 miles wide. ti\j,. 214. — .Ml. biiasta, California. On the right is Shastina, a newer cone on the flanks of the main volcano. Both these cones are extinct ; but Shastina still has a crater, while the crater of Shasta has been destroyed by denudation. Fig. 216. — Topographic map of Crater Lake. Notice the other smaller craters and cones near by. A section through the mountain, along the line AB, is shown at the bottom, (Crater Lake Special Sheet, U. S. Geological Survey '^oographic Map.) An earthquake shock accompanies the opening of the fissure, and huge volumes of steam rise from the glowing lava that rushes forth. At first the lava flows rapidly down the mountain side ; but it soon cools and solidifies at the surface (Figs. 217, 218). Then the movement becomes much slower. The frozen crust is broken and rolled along by the movement of the lava beneath, and liquid lava may burst through the solid front at any point. The lava front advances for weeks, always more and more slowly, and years may pass before it entirely cools. Summary. — Hawaii, the greatest volcanic mountain in the world, has two active volcanoes with huge craters, or calderas. In these are lava lakes ivhich steadily rise, once in about seven years being drained through fissures in the mountain sides. The lava at first fiows rapidly; but, as it cools on the surface, its rate offiow is checked. 87. Mt. Shasta and Lassen Peak. — This extinct volcano (Fig. 214), whose elevation is over 14,000 feet, resembles Etna in form. From its snow-covered top small glaciers descend into the higher valleys, and on its flanks is a later cone. South of Shasta is the extinct cone of Lassen Peak, and near its base an ash cone about 650 feet high (Fig. 235). The size of trees that have grown in the ash indicates that it was erupted about 200 years ago. A still later lava eruption has dammed a stream, forming Snag Lake, in which are snags of trees killed by the rise of the water. It seems probable that this lava flow is not much ovor a century old. There are other recent lava flows in various parts of the West. 88. Crater Lake. — Another extinct volcano in western United Statc-ii '^si occupied by Crater Lake in Oregon. This lake, which is about 2000 feet deep, lies in a huge crater, or caldera (Fig. 216), between 3000 and 4000 feet in depth, and about 6 miles in diameter. It has been proved that a lofty volcano (Fig. 219) rose where the caldera now stands. The removal of lava from named Mt. Mazama, restored by the dotted line. 89. Materials Erupted. — Every volcanic eruption is accompanied by vast quantities of steam, and smaller amounts of sulphurous and other gases. These gases are commonly called "smoke," and the glow of light reflected from the melted lava is popularly termed "flame." If the eruption is moderate, melted rock usually flows out, and, in cooling, forms lava flows (Figs. 217, 218). Expansion of steam in the pasty lava makes many small rounded cavities, especially near the top ; and the surface is broken by the movement of the lava after a crust has been formed. In violent eruptions the expansion of the steam blows the lava to pieces, forming scoria^ pumice^ and ash. These are so light and porous that they float in water, and the fine ash even remains suspended in the air. Lumps of lava thrown into the air, cooling in oval, twisted masses, are known as volcanic bombs (Fig 236). They vary from a few inches to many feet in diameter. During eruptions ilie condensation of the steam causes heavy rains, accompanied by vivid lightning. The rain often washes down much loose ash, forming mudjtoics. Summary. — Steam and other gases accompany/ all volcanic eniptions. Lava comes from moderate eruptions ; ash, pumice, and scoria from violent ones. Volcanic bombs are also thrown out; and rains wash down the ash, forming mudjloivs. 90. The Forms of Volcanic Cones. — A volcano is a conical peak with a crater at the top. If the eruptions are of ash the cone is steep, because the fragments that fall back near the vent have aslope as steep as loose ash will stand (Fig. 221). On the other hand, cones made of flowing lava are broad and have a low slope (Fig. 221). (Compare Figs. 223 and 224.) One reason for these differences is that lava flows away as a liquid ; another, that some of it starts, not from the top, but from fissures on the slopes of the cone (Figs. 210, 211) ; and a third that it all remains on the cone, while in ash volcanoes a large part is drifted away by the winds. When the material is now ash, now lava, as in Vesuvius, the cone has a slope intermediate between that of lava and ash. The crater of a volcano may be so large, perhaps from one to five miles in diameter, as to deserve the name caldera. In addition to the calderas of the Hawaiian Islands (p. 120) and Crater Lake (p. 121), there are calderas in Italy, the Eifel district of Germany (Fig. 225), and other places. The craters on the moon (Fig. 14) are enormous calderas. Calderas may be caused either by collapse of the cone, or by violent explosions Avhich blow the top of the cone away. In some cases, as in Krakatoa (Fig. 220), explosions wreck the cone and make it irregular. Summary. — Ash cones have a steep slope, ivhile lava cones are broader and more gentle in slope. Cones consisting of both ash and lava have a slope between the tioo. Calderas are huge craters caused either by the collapse or by the bloiving away of the tops of cones. 91. Distribution of Volcanoes. — There are thousands of volcanic cones, only about 300 of which are known to be active. The great majority of these cones are in or near the sea, far the greatest number being in the mountains and islands which partly encircle the Pacific Ocean (Fig. 222). The many lofty cones in the Andes, Central America, and southern Mexico are in this belt. Associated with it is the volcanic belt of the Lesser Antilles, 500 miles long, in which Mont Pele and La Soufriere are situated. Most of the islands of the Lesser Antilles are volcanic. From Mexico northward, through western United States, are hundreds of volcanic cones, all either dormant or extinct. Among the best known of these are Mt. Ranier, Mt. Shasta, Mt. St. Helens, and Mt. Hood. The Aleutian Islands, which inclose Bering Sea, form a volcanic chain 1600 miles long, including 57 volcanoes, some of which are very vigorous. From Kamchatka southward, along the Kiirile, Japanese, and Philippine islands, there is another great chain of volcanoes. The East Indies have numerous active cones, and this chain swings down to New Zealand. with a veneer of coral. There are volcanic areas in the continents of Europe, Asia, and Africa, including a line extending from central Africa to Asia Minor; also Mt. Ararat; volcanoes in the Caucasus Mountains; and a number in the Mediterranean near Greece, and in and near Italy. The islands of the open Atlantic are volcanic, and some of them are active. Iceland has a number of volcanoes, some of which have had terrific eruptions. The Faroe Islands are ancient volcanoes, and there were formerly volcanoes in the British Isles. In the Azores Islands, which are all volcanic, there are hundreds of cones (Fig. 226), some of which were in eruption during the last century. The Bermuda islands are a coral group on a volcanic cone. The Cape Verde, Canary, and other islands farther south, including St. Helena, the prison home of Napoleon, are all volcanoes. • In spite of the great numbers of cones, they are really exceptional land forms. By far the greater part of the earth's surface is now free from volcanic action; and large areas have never been disturbed by eruptions. In other places, as in eastern United States, central France (Fig. 227), and the British Isles, volcanic action long ago died out. Both at thp present time and in the past, volcanic activity has been associated with mountain growth Fig. 221. — The slopes of two volcanoes, one ash (dotted), the other lava. The latter, represented by the continuous line, may be considered to be Mauna Loa. Not only is the ash cone steeper, but it contains much less material, because so much has been drifted away by winds and ocean currents. See also Figs. 223, 224. crater. The stone walls by the roadside are made of lava blocks. Fig. 227. — Volcanic peaks in the Anver^ne region, a volcanic region in central France. The peaks on which the buildings are situated are remnants, or necks, of volcanoes partly destroyed by denudation. Summary. — The majoritu of volcanoes are in or near the sea, the greatest dclt heing in the chain of mountains and islands ichich partly encircle the Pacific. There are many volcanic islands in the open Pacific, Indian, and Atlantic oceans, and in the Mediterranean. Volcanoes are exceptional land forms. They have never been present in some places and have become extinct in. others. 92. Cause of Volcanoes. — The immediate cause for a volcanic eruption is undoubtedl}^ the explosive force of pent-up steam. It is believed that this steam is caused by water that percolates clown to the melted rock. As it slowly accumulates, it finally gains force enough to push its Avay to the surface and carrv some of the melted rock with it. It is probabk that the folding of the mountain rocks squeezes the lava upward until it reaches places so near the surface that water is able to enter it and force it the rest of the way. Faults formed during mountain growth furnish pathways for the rise of this lava. When mountains stop growing, volcanic activity dies out. For this reason western United States, which in the last geological period was a region of intense volcanic activity, is now almost, if not quite, free from active volcanoes. There may yet be eruptions in the West ; but unless there is a renewal of mountain growth, these eruptions will probably not be numerous. Summary. — Water, descending from the surface, comes in contact with melted rock, probably squeezed upward during mountain folding . This forms steam and forces the lava to the surface, often along faults. When mountain growth ceases, volcanic activity dies out. 93. Lava Floods. — In western United States, in addition to volcanoes, there were great lava floods which escaped from fissures and deluged the surrounding country. They were Perhaps squeezed out as a result of mountain growth, somewhat as water rises through a crack in the ice of a frozen pond. The greatest of these floods was in the valley of the Snako and Columbia rivers CFigr. 476). mainly in Oregon, Idaho, and Washington, where an area of fully 200,000 square miles is covered with lava. By these lava floods, which extended up Valleys and surrounded mountains, as lake water does, an irregular land surface was changed to a great lava plateau. Deep canyons show a depth of 3000 to 4000 feet of lava, layer on layer. In some places, as in the Cascade Ranges, blocks of this lava have been broken and tilted to form mountains. Throughout the Far West there are other instances of lava floods, for example, in the Yellowstone Park. Similar floods have been formed in other parts of the world, as the plateau of the Deccan in India, which in extent rivals the Columbia lava plateau. At present such lava floods are nowhere issuing from the earth. The nearest approach is in Iceland, where lava, welling from fissures, has built a broad plateau. When such a fissure is partly closed, leaving only one or two places for the lava to escape, volcanic cones are built along it. This accounts for some of the chains of volcanic cones. Summary. — Great lava floods, rising tlirougli fissures, and perhaps squeezed ovt by mountain growth, have deluged large areas of country in ivestern United States and other I'egions. Iceland has the nearest approach to this condition at present. TJie closing of most of a fissure allows the formation of a line of volcanic co7ies. 94. Lava Intrusions. — Not all the lava that starts toward the surface reaches it. For example, when eruptions cease, the vent of a volcano becomes filled with solid lava. This is called the volcanic neck or plug (Figs. 34, 227, 231). The long, narrow sheets filling the fissures, through which lava escapes on the flanks of a volcano, are called dikes (Fig. 34). In the neighborhood of volcanoes, similar dikes are intruded into the rocks (Fig. 232) deep in the earth. These and other forms of intruded rocks are brought to light by denudation. Fig. ^9. — Mt. Tom, Massachusetts, a ridge formed by a sheet of lava that was intruded into the sandsto-ne strata several geological ag^ ago, then Mlte«l and warn into its present mountain form. Fig. 230. — Columns caused by the jointing of an ancient sheet of lava at Giant's Causeway, Ireland. The columnar jointing is the result of the breaking of the lava as it coolsd. (See Fior 228.) Tig. 231, — Mato Tepee, Wyoming, a volcanic neck or plug. All the otlier material has been removed bv den'^datian- i'>aving the hard lava ulusr stsnn ^w.v oVv.^ro thfl surround UK country (See ^so, Fijpr ♦jiy' > their position by intrusion into the strata, A large mass of intruded lava which raises the strata to form adome is called a laccolith, or rock lake (Figs. 164, 233). Irregular masses of intruded lava form bosses (Fig. 34), often made of granite. These are found in the cores of old, worndown mountains, as in the Adirondacks, New England, Scotland, and Norway. Summary. — Various forms of intruded igneous rocks — necks, dikes, sheets, laccoliths, and bosses — are caused by the rising of lava that does not reach the surface. TJie 95. Life History of a Volcano. — While a volcano is active the cone usually grows, because each eruption acids material to it. A dormant volcano may, however, break forth in so violent an explosive eruption that the cone is wrecked and its size and form changed (Figs. 199, 220). Or, by the opening of a new outlet, the lava may be drained from beneath. for changes in the form of volcanoes are accidental. Throughout the life of every volcano the agents of denudation are at work tearing it down ; but so long as it is active, fresh supplies of lava or ash tend to repair the damage. When the volcano becomes extinct, however, denudation has full sway. At first the crater is occupied by a lake (Figs. 216, 225), but the rim is slowly destroyed and the lake drained. Streams gully the cone with deep ravines and gorges, until it bears little resemblance to a volcano. As the cone is slowly worn down, the hard core of lava in the volcanic neck resists denudation better than the looser beds of porous lava and ash. It therefore remains abov^e the surface as a central divide for radiating streams (Figs. 227, 231, 237). In western United States there is every gradation from the perfect cone to the volcanic neck remnant. If a volcano stands in the sea, the waves have a large share in its reduction (Fig. 234). At first, steep cliffs are cut, on which the waves beat with such force that no boat can land. As these cliffs are pushed back into the land, the crater may be reached and a crater harbor be opened (Fig. 234), Further wave cuttir.g may entirely consume the volcano, leaving only a shoal to mark its site. Summary. — - During activity a volcano gi'otv.^ hy addition of lava or ash faster than denudation wears it away ; but exjylosion or collapse may change its size or form. WJien extinct, ho2vever, volcanoes are slowly worn aivay, the last remnant being the hard volcanic neck. Waves aid in the destruction of cones in the sea. 96. Importance of Volcanoes. — The most noticeable effect of volcanoes is the destruction of life, — human, plant, and animal. The ash, lava, steam, gases, hot water, mud flows, lightning, and earthquakes that accompany eruptions all contribute to this destruction. Nothing in nature is more terrible than a volcanic eruption. Yet volcanoes have some beneficial effects. The burial of 01 ganic remains beneath ash and lava has preserved fossils that throw much light on the history of former life on the globe. The eruption of Vesuvius in 79 has preserved a record of Roman life that we could not in any other way have obtained. Lava flows have also covered and preserved deposits of precious metal, as in California, where some of the gold mining is carried on in ancient river gravels beneath old lava flows (Fig. 238). Volcarivjes have formed many lakes, like Nicaragua in the Isth. mus of Panama. Volcanoes and lava floods have helped make grand scenery. There are few finer sights than a large, snow capped volcanic cone, like Etna, Ranier, Hood, or Shasta, Lava soils are usually very fertile ; for example, one of the most productive wheat regions of the country is the Columbia valley, with its rich volcanic soil. Lava and ash have supplied much of the material of which the sedimentary strata are made ; and igneous rocks have supplied underground water with much valuable mineral for deposit in veins. Lava also heats the water, thus giving it more power to dissolve minerals. The presence of lava in western United States has had a very important influence on the formation of the valuable mineral veins of that region. Summary. — Volcanoes are very destructive to life; but they have some beneficial effects. They preserve records of past life, and occasionally valuable minerals; they cause lakes; they aid in the making of scenery ; their soils are usually fertile ; they have helped sui^ply material for the sedimentary strata; and they have aided in the formation of mineral veins. EARTHQUAKES. 97. (A) Cause. — During mountain growth a jar, or earthquake, is sent through the rocks when they slip along fault planes. Sometimes, as in Japan, in 1891, the surface of the ground on one side of a fault plane is raised during the shock (Fig. 239). Volcanic explosions, and the rush of lava into fissures, forming dikes, also cause earthquakes. In fact, an}^ jar to the rocks, as an explosion of gunpowder, the falling in of caverns, or an avalanche, will cause an earthquake. The jar may be so slight that it can be detected only by delicate instruments; or it may be so violent as to cause widespread destruction. (B) Occurrence. — Since earthquakes are so commonly caused by the breaking of rocks and by the movements of lava, volcanic regions are especially liable to them. Indeed the lava flows covered. Fig. 239. — Fault which caused the earthquake shock of 1891 in Japan. By this fault the road in the middle of the picture was raised several feet on the farther side of the fault plane. (See Figs. 241, 242.) Fig. 240. — A drawing to illustrate the movement of an earthquake wave outward in all directions from the focus, F. The shock reaches the surface first at E, the epicentrum, and at later and later periods on the circles marked J. a map of the distribution of volcanoes might also serve as a map of frequent earthquakes. To be sure, there have been violent earthquake shocks far from volcanoes ; for example, those of Lisbon, Portugal, in 1755, southern Arkansas in 1812, and Charleston, S.C., in 1886. Such shocks are usually due to the slipping of rocks along a fault plane. (C) Cliaracteristics. — The center, or focus (Fig. 240), of an earthquake may be thousands of feet beneath the surface. From it the jar passes through the rocks in all directions (Fig. 240), in much the same way as a shock passes through a table when it is struck a heavy blow. The point above the focus, where the shock is first felt at the surface, is called the epicentrum. At the epicentrum the movement of the earth is vertical, and the shock is most violent. As the distance from the epicentrum increases, the shock is felt with less and less violence. The Charleston earthquake was detected by delicate instruments as far away as Ontario, Canada. In an earthquake shock the ground may not rise and fall more than an inch, and yet do great damage. The earthquake is rarely a single shock, but usually a succession of jars, perhaps near enough together to give the appearance of a shaking of the ground. Very often one earthquake quickly follows another; for example, in 1783 nearly 1000 shocks were felt in Calabria, in southern Italy. In this case the rocks were probably slipping along a fault plane, and each slip sent out an earthquake. The many earthquakes that precede a volcanic explosion are no doubt due to the breaking of the rocks by the attempt of the steam-filled lava to escape. (D) Effects. — Violent earthquakes are very destructive (Figs. 241, 242). They often cause avalanches, which dam streams and form lakes ; and the shaking of the ground sometimes forms diepressions, in which lakes and ponds gather. Trees are thrown down ; cracks, in which plants and animals are swallowed up, are opened in the ground ; and great destruction of life is caused by the overturning of houses {Fig. 241). In consequence of the danger from falling houses, people who live in countries where earthquakes are frequent, build their houses so that they will withstand ordinary shocks. Even with this precaution, thousands of lives are sometimes lost in a single shock. If the shock is in the sea, a water wave may be started which causes much destruction on low coasts (p. 186). Summary. — Earthquakes are jars in the rocks, resulting from faulting, volcanic action, and other causes. Tliey are most common in volcanic regions, hut sometimes occur elsewhere. An earthquake, usually a series of shocks, is most violent at the epicentrum {point above the source, or focus, of the shock), diminishing in intensity in all directions from it. Earthquakes form lakes, open cracks in the ground, and throw down trees and houses, causing great destruction of life. If in the sea, a destructive water wave may he started. HOT SPRINGS AND GEYSERS. 98. Underground water is often heated by buried masses of lava or other causes. Where this heated water rises to the surface, usually through a fissure, it forms a hot spring ; and if it occasionally gushes out, it is called a geyser. The rising hot water always bears mineral substances in solution, some of which may be deposited near the spring. Such deposits are found around the hot springs (Figs. 243, 474) and geysers (Figs. 244, 473) of Yellowstone Park. Hot water is sometimes encountered in mines, and it is known that many veins of gold, silver, copper, and other valuable metals have been deposited by hot water on the walls of fissures. There are geysers in New Zealand, Iceland, and "the Yellowstone National Park — all volcanic recfions. The mineral deposits made around these are often very beautiful in form a^d color, and they sometimes build a cone, through the crater of which the geyser erupts (Figs. 244, 473^. Fig. 241. — Destruction caused by the Japanese earthquake of 1891 (Fig. 239;. All this damage was done to houses that were built very lightly and thus able to withstand ordinary earthquake shocks. Fig. 243. —Hot spring deposits in the Yellowstone Park. These deposits are carbonate of lime (calcareous tufa) , and they build little basins in which the hot water stands, trickling over the edge and forming icicle-like deposits. The geysers are exceedingly interesting. Old Faithful erupts every 65 minutes, with such regularity that the time i^i each outburst- can be accurately predicted. With each eruption a great mass of hot water and steam is thrown to a height of over 100 feet. The Minute Man geyser erupts a small column every few minutes to a height of only a few feet. Other geysers erupt very irregularly, and some have become extinct. The differences between the geysers suggest the probability of several explanations for their eruptions. Those that erupt regularly, like Old Faithful, seem to be due to the following cause. There is hot water in a narrow tube ; and this is heated, perhaps by an adjacent lava mass, until the boiling point is reached. The boiling point of water rises under pressure ; therefore, it may be necessary to raise the temperature to 250° or more before boiling begins down in the tube. When the boiling point is reached steam forms, but the narrow tube prevents its easy escape. It then lifts the column of water and causes some of it to flow away from the geyser crater. This overflow removes some of the water column and therefore reduces the pressure on water that is already boiling at 250°. This removal of pressure at once lowers the boiling point ; and, since a large mass of water has a temperature near 250°, it suddenly changes to steam. This expels the water with a rush. The time between eruptions depends upon the length of time required to heat the water down in the tube to the boiling point. Summary. — Hot water, rising from underground, forms hot springs ; or, if it rises in eruption, geysers. It hears and deposits mineral substances, both at the surface and in the fissures through which it rises — m the latter case sometiynes forming valuable mineral veins. Some geysers erupt regularly, others very irregularly. Topical Outline. — 80. Graham Island. — The eruption ; materials ^.rupted; the cone ; its destruction ; other volcanoes. 81. Stromboli. — Location ; size of cone ; nature of eruptions. 82. Eruptions of 1902 in the West Indies. — Destruction of St. Pierre; La Soufriere ; previous eruptions ; warnings ; eruption of May 8 ; causo of destructiveness ; effects of later eruptions ; material erupted ; distribution of ash ; mud flows ; probable future. 83. Vesuvius. — (a) Eruption of 79 : previous condition ; settlements on slopes ; warnings ; effect of eruption ; our knowledge of the eruption ; conditions accompanying eruption. (6) Pompeii : importance of its excavation, (c) Condition since 79: difference in eruptions; present condition; ordinary quiet ; increase in activity ; lava eruptions; observatory, (f/) Other volcanoes of Bay of Naples. 86. Hawaiian Volcanoes. — (a) Island of Hawaii: its volcanoes; its height. (&) The craters: lava lakes; calderas. (c) Lava flows: rising in crater; draining through fissures ; length of flows ; nature of flow. 91. Distribution of Volcanoes. — Number ; general location ; belt encircling Pacific, — South America, Antilles, western United States, Aleutian Islands, eastern Asia ; other chains, — Pacific and Indian oceans, continents, Mediterranean, open Atlantic; areas free from volcanoes; areas of extinct volcanoes ; association with mountains. 93. Lava Floods. — (a) Columbia valley: cause; area; lava plateau; thickness; later tilting, (b) Other areas, (c) Present condition : general •absence of lava floods ; Iceland; relation of fissures to volcanic cones. 96. Importance of Volcanoes. — Destruction of life ; preservation of fossils ; oi human records ; of mineral ; formation of lakes ; effect on scenery; on soils; on sedimentary rocks; on mineral veins. 97. Earthquakes. — (A) Cause: faults; volcanic action; other causes. (B) Occurrence: volcanic regions; other regions ; illustrations. (C) Characteristics: focus; nature of shock ; epicentrum; distance trav- 98. Hot Springs and Geysers. — Cause ; nature of geysers ; mineral deposit at surface ; mineral veins ; distribution of geysers ; geyser deposits ; eruption of geysers ; explanation of geyser eruptions. 82. What reasons were there for expecting an eruption? Why was the eruption so destructive at St. Pierre? What were its effects? What was the nature of the material erupted ? What causes mud flows? 83. What was the condition of Vesuvius in 79 ? Tell about the eruption of 79. How has it been of importance? What has been the subsequent history of Vesuvius? What is its present condition ? What other signs of volcanic activity are there near Vesuvius? 96. State the important effects of volcanoes. 97. (A) What are the causes of earthquakes? (B) Where are they most frequent ? Why? What explains violent earthquakes elsewhere? (C) What is the focus? The epicentrum? What is the nature of the shock? (D) What are the effects of earthquakes ? Suggestions. — (1) Illustrate the formation of volcanoes. Take an ordinary wooden box, for example a soap or shoe box, remove the cover and turn it on its side with the bottom toward the class and the open side toward the teacher. Extend a glass tube through the top of the box and blow sand gently through it. A cone will be built with a crater in the center. The force of the eruption njay be made to vary, and many phases of volcanic eruptions may be imitated. The sand is best blown through by means of foot bellows, and the result will be more satisfactory if the lower part of the tube is expanded into a bulb that is partly filled with sand. (2) In the same way, force melted wax up to form a volcano. Have a branch tube extend oif, reaching an inch or two above the top of the box. Keep its end plugged until the wax covers it, then open it and plug the main tube, allowing the wax to escape through the side tube to illustrate the eruption of lava from the sides of a cone. If the wax solidifies in the tube and interferes with the experiment, warm the tube. (3) With a little ingenuity wax can be forced between layers of clay and cardboard, forming laccoliths; or into fissures cut through the layers, forming dikes. (4) Look for dikes. If your home is along the rocky coast of New England, they may easily be found. Study them and tell what you observe. (5) Students in the Connecticut valley, New York City, and east central New Jersey should be given an excursion for the study of the trap sheets. Look for jointing. Look for the rock strata above or below the lava. How do they differ from the trap? Make careful observations. (6) Earthquakes may be imitated and studied by jarring a slab or stone or a table top. (7) A geyser eruption may be made by constructing a long (two or three feet), narrow tube, filling it with water, aiid heating it near the bottom until steam is produced. Reference Books. — Russell, Volcanoes of North, America, Macmillan Co., N.Y., 1897, $1.00 ; Heilprin, Mt. Pelee and the Tragedy of Martinique, Lippincott, Philadelphia, 1903, \|3.00; Hull, Volcanoes, Scribner's Sons, N.Y., 1892, -11.50; Judd, Volcanoes, Appleton & Co., N.Y., 1881, $2.00; Dana, Characteristics of Volcanoes, Dodd, Mead & Co., N.Y., 1891, \|5.00 ; Lyell, Principles of Geology, Chapters XXIII-XXV, Appleton & Co., N.Y., 1877, 18.00; Bonney, Volcanoes, Putnam's Sons, N.Y., 1899, $2.00; Geikie, Ancient Volcanoes of Great Britain, 2 vols., Macmillan Co., N.Y., 1897, $11.25; Dutton, Hatvaiian Volcanoes, 4:th Annual U. S. Geological Survey, p. 8 ; Gilbert, Geology of the Henry Mountains, Washington, 1877 (out of print) ; Diller, Mt. Shasta, National Geographic Monographs, American Book Co., N.Y., 1895, $2.50; Diller, Crater Lake, Annual Report, Smithsonian, Institution, 1897, p. 369; Milne, Earthquakes, Appleton & Co., N.Y., 1891, $1.75; Dutton, Charleston Earthquake, 9th Annual U. S. Geological Survey, p. 209 ; Weep, Hot Springs, 9th Annual IJ. S. Geological Survey, p. 619. GLACIERS AND THE GLACIAL PERIOD. 99. Valley Glaciers. — The snow line in the Alps is about 9000 feet above sea level. Above this line is a great snoiv field (Fig. 245, 249), in which snow accumulates year after year, in some places reaching a depth of hundreds of feet. Some of the snow is whirled away by the wind, settling in valleys ; some slides down the steeper slopes (Fig. 246), as snow slides from the roof of a house. There is so much snow falling into the valleys, both as small slides and great avalanches, that they would be completely filled if it could not in some way be removed. The snow that accumulates in the valleys gradually changes lo granular snow ice, resembling the snow banks of late winter. .This change is partly due to the pressure of the overlying mass, and partly to alternate melting and freezing during summer days and nights. The granular ice, called the neve (Figs. 246, 248), moves slowly down the steep valleys. As the mass moves, pressure and further melting and freezing gradually change it to pure, clear ice. The supply from the snow field causes the ice to move down the valley, much as a river extends beyond the place where the rain fell. Such an ice tongue, occupying a valley, is called a valley glacier (Figs. 15T, 181, 185, 247-251). In the Alps some of the glaciers are 10 to 15 miles long, extending 4000 or 5000 feet below the snow line. They end where the warmth is sufficient to completely melt the ice, and the terminus may be below the timber line, even in the zone where grain will grow. of wax does when under pressure ; that is, it moves as if it were slowly flowing. The most rapid motion is near the middle, though even here it does not usually move more than two feet a day. Every glacier carries rock fragments, some of which have fallen from the valley sides, while others have been obtained from its bed. These fragments, slowly dragged along, and pressed down by the weight of the ice, groove, striate, and scour the rocks over which the glacier moves. It may be compared to the work of sandpaper. By this scouring, known as glacial erosion^ valleys are both deepened and broadened. Bands of rock fragments, accumulated on the margin of the glacier, where they have fallen from the cliffs, are known as lateral moraines (Figs. 247, 249). Where two glaciers join, two lateral moraines unite, forming a medial moraine (Figs. 249, 250), near the middle of the glacier. The surface of the glacier melts in summer ; but moraines protect the ice beneath from melting, and this causes them to stand up as ridges, often 50 feet or more above the surface of the glacier. Although ice under steady pressure slowly flows, when subjected to a decided strain it breaks, forming cracks, or crevasses' (Figs. 246, 248), in the glacier. Where the valley bottom is irregular, causing many strains in the moving ice, crevasses are especially abundant ; and when the slope of the bottom is steep, the ice may become so crevassed that it is almost impossible to pass over it. Such a section is called an ice jhll. Moraine fragments are constantly falling into these crevasses, some of them finding their way to the bottom of the glacier. Water from the melting ice also falls into crevasses, boring pot holes (p. 54) in the rock floor, and flowing in ice tunnels to the front of the glacier. The rock fragments frozen in the bottom of a glacier aru known as the ground moraine^ and when a glacier disappears by melting this is left as a deposit on the valley bottom. To it are added the materials of the lateral and medial moraines, which slowly settle to the ground as the glacier melts. At the end, or terminus, of a glacier, rock fragments are built into a" terminal moraine. These fragments are brought by the ice and loosened as it melts, accumulating in irregular piles at the base of the glacier front. If the end of a glacier remains in one place for a long time, the terminal moraine hills may reach a height of 100 or 200 feet. The water that falls into crevasses emerges as a stream from the ice front (Fig. 185), often from an ice cave. It is white with suspended sediment, or rock flour ^ supplied by the grinding up of rocks beneath the glacier. In summer, the volume of these glacier streams becomes so great that even pebbles are moved along. The clay is carried far down the valley, but the sand and pebbles are usually deposited on the valley bottom, gradually filling the valley. Over this deposit the stream flows in a branching, braided course, constantly depositing sediment and changing position (Fig. 251). Such ivash deposits may reach a depth of over 100 feet. Summary. — Snow, derived from the snow field, accumulates in the valleys, changing to granular ice {neve), then to ice, which extends down the valley as an ice tongue or valley glacier. As it moves, it scours its bed, aiid carries rock fragments, both on its surface (lateral and medial moraines) and at its bottom {ground moraine). Both rock fragments and icater descend to the bottom of glaciers through crevasses, caiised by strains resulting from the ice motion. The rock fragments form a ground moraine and assist the ice in erosion; the water emerges from beneath the ice in streams, bearing rock four, sand, and pebbles, ichich build extensive icash deposits Terminal moraines are built at the ice front. 100. Glaciers of Alaska. — Of the many Alaskan glaciers the best known is the immense Muir glacier (Figs. 253-255), which is fed by twenty glacier tributaries or more. These unite to form an ice tongue which advances down a broad valley and ends in the sea. Its front is a cliff, rising 200 feet above the water and extending 700 or 800 feet below. From it small icebergs frequently break off and float down Farther north is another large glacier, the Malaspina (Fig. 252), formed by the union of a number of valley glaciers that descend from the Mt. St. Elias range (Fig. 256). This glacier spreads out, fan-shaped, on a plain at the base of the mountains. For this reason it is called a Piedmont glacier (from jt??W, foot, and mont, mountain). It has a length of 60 or 70 miles and a breadth of 20 or 25 miles; and its movement is so slow that it is an almost stagnant, undulating ice plateau (Fig. 257). Melting ard evaporation have caused the rock fragments in the upper portion of the glacier to accumulate at the surface, especially near the lower end. These rock fragments form a rocky soil on the glacier, in which a forest is growing (Fig. 258). Summary. — 3Iuir glacier, fed by over Urenty trihntary glaciers, ends in sea cliffs from which icebergs are discharged. Malasi}ina glacier^ an almost stagnant ice plateau, is called a Piedmont glacier. 101. Distribution of Valley Glaciers. — There are several liuiidred valley glaciers in Switzerland, and these serve as one of the attractions to tonrists. There are also many in the Cancasus and Himalaya mountains, and in Norway, where some descend to the sea. There are small glaciers in some of the high mountain valleys of Mexico (in the tropical zone) and of western United States. Toward the north glaciers increase in size and number, becoming especially large and abundant in western Canada and Alaska. Tourists are beginning to visit the Selkirk range of western Canada, which rivals Switzerland in the grandeur and beauty of its snow-capped mountains and its glaciers. The Muir glacier is also regularly visited by steamer. The islands of the Arctic, such as Baffin Land, Iceland, and Spitzbergen, have innumerable valley glaciers, many of which descend to the sea. Glaciers are also abundant in New Zealand and the southern Andes. Summary. — Valley glaciers exist in many parts of the loorld, eveyi in the tropical zone. In cold climates they occupy loio valleys, and even descend to the sea; in warm climates they are confined to the upper valleys of high mountains. 102. Former Extension of Valley Glaciers. — It is well known that valley glaciers were formerly more extensive than at present. In fact, they once existed in places where now there aje none. Nearly all Switzerland was once covered by an ice sheet, formed by the union of valley glaciers; there were many in the Rocky Mountains ; and glaciers existed even in the Adirondacks and New England mountains. The clear evidence of this former extension of glaciers is of various kiads, as follows : (1) rock fragments, called erratics (Fig. 259), often weighing tons, are found in the valleys. In many cases they are different from the rock near by, but are the same as rock found higher up the valley. They have apparently been brought by some powerful agent, like ice. the direction in which the erratic hoivlders have been carried. (3) Deposits like those now being made by glaciers occur in the valleys (Figs. 251, 260). These include lateral, medial, terminal, and ground moraines, the ground moraine making a thin sheet of mixed clay, pebbles, and bowlders, called bowlder clay or till. This till is unlike water deposits, being unassorted and unstratified ; but it is like deposits from ice, which carries and drops large and small fragments with equal ease, and, therefore, side by side. In front of the terminal moraines, and sometimes mixed with them, are wash deposits of stratified gravels, like those now being laid dowji by the streams that issue from glaciers. (4) The valleys also show signs of glacial erosion (Figs. 251, 259, 261, 262). The rocks of their sides and bottoms are polished by ice scouring, and the ledges are worn into smooth, rounded curves, known as roches moutonnees (sheep backs). This erosion has often broadened and deepened valleys (Fig. 261); and where they have been deepened a little more than elsewhere, i^ock basins have sometimes been formed, now occupied by lakes and ponds. In some cases the valleys have been deepened hundreds of feet ; and in the region of former neve, broad deep amphitheaters, called cirques, have been formed. Since the ice disappeared, side streams tributary to these ice^ eroded valleys have not had time to cut their bottoms clown to the level of the deepened main valleys. Their bottoms therefore stand above the level of the main valley, and they are accordingly called hanging valleys (Fig. 293). From them the streams tumble into the main valley as falls or rapids. These waterfalls add to the charm of the mountain scenery in Switzerland, Norway, Alaska, and other regions from which glaciers have departed. Summary. — Erratics, strice, moraines, till, and wash dejiosits are among the evidences that valley glaciers were formerly more extensive, and even existed where noiv there are none. Evidences of ice erosion are also foiLnd, in the form of roches moutonnees, broadened and deepened valleys, rock basins, cirques, and hanging valleys. Fig. 259. — The top of a Swiss glacier, showing crevasses. Beyond it is a smoothed, P'^ratched rock surface with erratic bowlders on it. The ice has left this surface so recently that vegetation has not had time to occupy it. glacier formerly extended, deepening it. Fi«. 262. — A view on the Grimsel Pass, Switzerland, showing a smoothed rock valley with little lakes. This was formerlv occupied by a glacier which has BOW pntlrf^lv disappeared^ leaving scwwed leot'-k svi«»«,9jrni rrowj.iTvo hIo 103. The Greenland Ice Sheet. — The island of Greenland is mountainous, not greatly unlike northern New England and Scotland. Near the coast there is a fringe of peninsulas and islands on which there are scattered Eskimo settlements. The mountain valleys have valley glaciers, and small ice caps exist on some of the larger islands and peninsulaSv Fig. 263. — A map of the region around the Cornell glaciei* where Figs. 264, 265, and 271 were taken (near the long peninsula at the top). The arrows show the general movement of the ice, outward from the interior, but turning down into the valleys, and ending in tongues in the bays and fiords. Back of the fringe of coast land is a great waste of ice and snow, with an area of about 500,000 square miles, moie than ten times the area of New York State. This enormous ice cap is sometimes called the Greenland glacier; but it is so large, and, in a number of ways, so diflterent from what is commonly called a glacier, that the term ice sheet is a better name. An ice sheet is a mass of ice, covering and moving over a large area of land, Idll and valley alike. In the interior, a part of which Peary has crossed, the elevation is 8000 to 10,000 feet, and the temperature never rises above the freezing point. The surface is, therefore, always covered with loose, dry snow. Nearer the coast, where the elevation is less, the warmth of the summer sun melts the snow, leaving an ice surface quite like that of valley glaciers. The continued fall of snow on the high interior of Greenland has caused such an accumulation that, changed to ice by pressure, it is forced to move slowly outward (Fig. 263) in all directions, — north, east, south, and west. It moves as a great pile of wax would, and in its slow, irresistible outward movement crosses hill and valley alike. Back of the coastal fringe the only land that appears is an occasional high mountain peak, called a nunatak (Fig. 264), which projects like an island above the sea of ice. Near the coast the ice extends down the valleys, often reaching the sea (Figs. 263, 264). At the head of fiords these valley tongues end in sea cliffs 200 or 300 feet high (Fig. 265), advancing in some cases at the rate of from 50 to 75 feet a day, and discharging huge icebergs that float into the Arctic (Figs. 267, 268, 339). Most of these tongues are only a few miles wide ; but the largest of all, the Humboldt glacier of north Greenland, is 60 miles wide. Their surface is broken by crevasses, quite unlike the smooth, unbroken ice plateau of the interior. Unlike that of valley glaciers, the surface of the ice sheet is quite free from rock fragments, excepting where nunataks supply materials for a medial moraine, or, near the end of a valley tongue, where cliffs rise from the ice margin. Near the bottom, however, there is much rock material, which has been worn from the land. In transporting this load of rock fragments at its base, the ice sheet scours its bed and does much work of erosion. Melting near the margin causes streams and even ponds Fig. 264. — A view of the Greenland ice sheet, showing its vast expanse, its extension into the fiord valleys, and a nunatak rising above its surface. This is a view of the Cornell glacier, one of the large valley tongues of the Greenland ice sheet. to form on top of the ice; and this water finds its way by crevasses to the bottom. Where this water emerges, either on the land or in tlie sea, deposits of gravel and clay are being made (Figs. 266, 272). Along the ice front, too, moraines are being built of rock fragments loosened by melting (Fig. 271). Many of these are worn and scratched (Fig. 290) by the grinding they have received. There is good evidence that the Greenland ice sheet, like valley glaciers, once extended much farther, completely covering some, if not all, of the islands and peninsulas. This evidence is supplied by moraines, erratics, glacial scratches, rounded and deepened valleys, and rock basins. The Greenland ice sheet, like the Muir and many other glaciers, is now melting back. Summary. — Greenland is covered by a great ice sheet, with a fringe of land near the coast, and, near the margin, occasional nunataks projecting above the ice. From the high interior, where snow falls summer and winter, there is a movement outward in all directions, the 7nargin of the ice consisting of valley tongues, often ending in the sea into ivhich icebergs are discharged. Tlie ice has little rock material on the surface, but carries much near the bottom, ivith which it is doing ivork of erosion and making moraine and tvash deposits. 104. Other Ice Sheets. — Qn the Antarctic continent there is an enormous ice sheet, of which little is known. It is generally believed that the entire South Polar region is covered by an ice cap, with an area larger than the United States. For a long distance its margin is a great ice wall, rising several hundred feet above the sea and discharging huge tabular icebergs. On the larger islands of the Arctic there are also ice caps, resembling that of Greenland, though smaller. There is evidence that ice sheets once spread completely over these islands. and smaller sheets on some of the larger islands of the Arctic. 105. Formation of Icebergs. — When a glacier enters the sea the water buoys the ice up, causing great masses to break off, forming icebergs (Figs. 265, 267, 268, 339). Other masses are broken away by undercutting along the water's edge. As the icebergs drift slowly away, they melt, strewing rock fragments along the sea bottom. They often run aground (Fig. 267), pushing and grinding the layers of sediment on the bottom. It is fortunate that the icebergs drift aivay from the glacier, otherwise the fiords would soon become choked with berg ice. They float away in an outward current of water caused by winds from the ice sheet and by fresh water from the melting ice. 106. Former Ice Sheets in Europe and America. — There is good evidence that, not many thousand years ago, a great ice sheet spread over northeastern America (Fig. 270), and another over northwestern Europe. Scandinavia, Denmark, northern Germany, northwestern Russia, and all of the British Isles, excepting southern Enorland, were then covered by ice. Canada east of the Rocky Mountains, New England, northern New Jersey, nearly all of New York, northern Pennsylvania, much of Ohio, and the states farther west and northwest, as far as Montana, were also ice-covered. These ice sheets, which were quite like those now covering Greenland and the Antarctic continent, have been called continental glaciers. - The proofs of these former ice sheets are of the same kind as those of former greater extension of valley glaciers (p. 141) and of the Greenland glacier (p. 145). These proofs include glacial scratches (Figs. 289, 291), glacial pot holes, and erratic bowlders (Fig. 285). The scratches point toward the north, and many of the bowlders can be traced to a northern source, some in the United States having come from Canada. There is also evidence of ice erosion and valley deepening; and there are lakes in rock basins that the ice scoured out (p. 158). Where the ice stood, the land is covered by a sheet of ground moraine, and there are bands of terminal moraine (Fig. 274), with wash deposits in front (Fig. 275). Tliese glacial deposits were called drift, because they were thought to the term glacial drift is still applied to them. Louis Agassiz, in the middle of the last century, first proposed the glacial theory to account for this drift. Being a Swiss, he had studied glaciers in Switzerland, and had seen the clear evidence (p. 141) that Alpine glaciers were formerly more extensive. He saw that the same evidence was present in the British Isles and in America, and proposed the theory that there had been a Glacial Period. This at first m.et a storm of opposition, but is now accepted by every one who has studied the question intelligently. Summary. — Strim, erratics, evidences of erosioyi, moraines, etc., jirove that great continental glaciers, or ice sheets, formerly covered northeastern America and northwestern Euroj^e. Louis Agassiz proposed the noio accepted explanation of the Glacial Period. 107. Cause of the Glacial Period. — Why there should have been a glacial climate in temperate latitudes is not positively known. At present the climate of Labrador, Scandinavia, and other centers from which the ice spread, is very cold ; and, if they were elevated se\^eral hundred feet, great ice caps might slowly gather on them and spread out into lower and warmer regions. Before the Glacial Period these lands actually were higher than now, and one theory is that this former elevation caused great ice sheets to form and move down into the United States and Europe. In the United States an ice sheet from Labrador joined forces with ice sheets from the Adirondack and New England mountains, and spread over hill and valley, advancing slowly and irresistibly, as the ice sheet of Greenland does. It advanced southward to a zone where melting became so great that it could go no farther. After many thousand years the climate gradually changed, perhaps because the land was lowered. We do not know how long ago the ice melted away, but there is evidence pointing to from 5000 to 10,000 years (p. 333). The time since the ice left is so short, however, that the drift deposits are still quite fresh ; and even delicate striae remain (Fig. 289) wherever protected by a thin coating of soil (p. 41). Summary. — One theory for the Glacial Period is that when the land was higher in Labrador ayid /Scandinavia, ice caps formed and spread out in all directions, and, after many thousand years, when the land was lowered, melted away. 108. Terminal Moraines. — While the ice sheet was melting back there were periods when it halted for a time and built terminal moraines (Fig. 274). These bands of drift deposited by water from the melting ice. Ice tongues, or lobes, extended farther in the valleys than on the hills, and on this account the moraines bend southward in the valleys, forming looped or lobate moraines (Figs. 269, 273). Terminal moraines were built at each halt of the receding ice sheet, and they are called moraines of recession (Fig. 273) . Summary. — At each halt of the receding ice sheet a terminal moraine was built with lobes extending doimi the valleys. These moraines are low, hummocky hills, with inclosed basins, or kettles^ often occupied by ponds. Fig. 269. — Lobate moraines in the Central States, showing the influence of the Great Lakes valleys in causing the ice tongues to extend farther south. Fig. 271. — Edge of the Greenland ice sheet on the land (near Fig. 264). The dai'k layers of ice are due to rock fratrinents. and the ridge in the foreground is a moraine built by the falling of these from the ice margin. H.UFaiivhild Fig. 2T>i. — The lobate moraines of recession in western New York. The outermost terminal moraine is the one that bends up from Pennsylvania to Salamanca and Olean. Also location of drumlins, and of shore lines of glacial lakes. The heavy line is the divide. The lakes have all been caused by glacial action. glacier when the moraine was being built. Compare Figs. 251, 266, and 272. Fig. 276. — A kame near Fig. 275. It is made entirely of strtltified gravel, and in the center, just above the tree to the right of the horse, has a very deep kettle hole that looks like a crater. 109. Stratified Drift. — Water issuing from the melting glacier built several classes of deposits. All these are stratilied, because water assorts rock fragments (p. 32). These stratified deposits are called stratified drift. Of these the most extensive are the wash plains (Fig. 275), which resemble those now forming in the Swiss valleys (p. 139). Many valleys in eastern America are filled to a depth of from 100 to 300 feet with these level, gravelly j)lains, built by ancient glacial streams. Wherever the ice front rested on fairly level land the glacial streams built a series of low, flat alluvial fans. The plains on the south side of Long Island are of this origin. At and under the ice front the water built irregular, hummocky hills of gravel, called kames (Fig. 276), in which deep basins, or kettles, are often found. Some of the kames were apparently made by streams, bearing much gravel, which tumbled to the bottom of the glacier through crevasses. This gravel occasionally covered blocks of ice which, on melting, allowed the gravel to settle, forming the kettle holes. Long, narrow ridges of gravel, sometimes miles in length, and with an irregular, serpentine course, are called esJcers (Fig. 282). These are the gravel beds of streams that flowed in tunnels or gorges in the ice, usually at the bottom. Where these streams emerged from their ice tunnels they built wash plains ; or, if the end was in small, ice-dammed lakes, they built deltas. These level-topped deltas are called sand plains. Summary. — Water fro7n the melting ice made stratified deposits : kames ivJiere streams tumbled to the base of the ice ; eskers where they flowed in ice tuimels ; ivash plains where they emerged upon the land ; and sand plains in small, ice-damnhed lakes. 110. Ice-dammed Lakes. — In some places the ice front stood in large lakes (Figs. 278, 279), formed where northflowing streams were dammed by the ice. Clay and gravel deposits were made in these, and along their shores deltas and beaches were built. One of tliesc large lakes was formed in the valley of the Red River of the North (p. 78). Other north-flowing streams were dammed by the ice, some of the valleys having small, others large, glacial lakes. The case of the Great Lakes is especially interesting. At first a few small lakes were formed, one outflowing past Chicago, one past Duluth, and one past Fort Wayne, Ind. (Fig. 280). As the ice melted back these grew larger, uniting and outflowing past the ice continued to melt back, a still lower outlet was opened eastward through the Mohawk valley (Figs. 277, 280), the Chicago outlet was abandoned, and for a while the glacial lakes outflowed into the Hudson past Little Falls, N.Y. Finally, when the ice disappeared from the St. Lawrence valley, the present course was established. The beaches that were formed at the levels of the different outlets of these various lakes may still be clearly seen. For example, the beach ridge from Syracuse to Lewiston (Fig. 273), on which the " ridge road " is built, was recognized as a beach by the early explorers. The fine-grained clay that was deposited on these lake bottoms makes a level, fertile soil. Consequently, the region between the elevated beaches lakes along its margin. Describe what you see. Fig. 279. — The same as Fig. 278 with the ice melted back somewhat, uncovering a valley which it had crossed. A moraine marks the former position of the ice front in the glacial lake. Describe what you see in this. orchards, and vineyards. The beaches are not horizontal, but rise toward the northeast at the rate of about three to five feet a mile ; and this is taken as proof that the land has been tilted since they were formed. As a result of this tilting, the lakes have changed from one outlet to another (Figs. 280 and 281). te mpo rary glacial rence valley, the land in the north was so low that the sea (shaded) entered the Champlain and Ontario basins, and the upper Great Lakes outflowed through the Ottawa River. Then Niagara carried the water only of Lake Erie. As the land in the north rose, the upper lakes were tilted until they finally overflowed past Detroit. peared ivheii the ice dam melted away. Lakes of this soi^t were formed in the valleys of the Great Lakes, shifting their outlets as lower ones were uncovered by ice melting, or made j^ossible by land tilting. The tilting of the land is still in progress. 111. Loess. — In central United States there is a sheet of finetextured clay known as loess, a German name for a similar deposit in that country. Some of the loess was evidently drifted by vinds, and some of it was brought from the ice front in slov.dy deposited, in others brought by sloidy moviyig sheets of icater, 112. The Till Sheet. — The principal soil of a glaciated country is till or bowlder clay^ which occupies the region between the moraines, wherever the surface is not covered by stratified drift. Till is a compact clay, usually unstratified, with bowlders and pebbles mixed through it (Fig. 283). It is the ground moraine left when the ice melted. The till sheet varies greatly in thickness, being usually thin where the rock is hard, and thick where it is soft and easily ground up. In Labrador, and in hilly New England, there are large areas with little or no till ; but in the Mississippi valley, where the land is more level and the rock softer, the till sheet is sometimes 100 or 200 feet thick. There is also much difference in composition. An abundance of bowlders is likely to be found just south of mountain areas of hard rock, as in New England, and south of the Adirondacks. They sometimes form trails, or hoivlder trains^ from the place of origin, growing less common and smaller as the distance from the source increases, because of the erosion to which they have been subjected. In ceritral New York, where the bowlders are largely hard rock from the north, farmers call them "hardheads." Summary. — Till or bowlder clay, the most imdespread glacial deposit, is the ground moraiiie. It is a sheet of mixed clay ant bowlders varying in thickness and in the proportion of bowlders. 113. Drumlins. — In many sections the till sheet is smooth and regular, covering the surface to a. fairly even depth; in other places it is ridged and irregular. One peculiar irregularity of till is the drumlin (Figs. 286-288). Drumlins vary from 100 feet to a mile or more in length, and from 20 to 100 or 200 feet in height. Some are long and ridge-like ; some short and lumpy ; but the most typical drumlins are oval, having the shape of a half-submerged egg (Fig. 286), with the long direction parallel to the water surface. They are masses of till ridged up under the ice. Drumlins usually occur in clusters. There is one group in Wisconsin, near Madison (Fig. 288) ; another in central New York between Rochester and Syracuse, and northward to Lake Ontario (Fig. 273, 287) ; another in the Connecticut valley ; another in and near Boston (Fig. 286). Boston is built on drumlins, of which Bunker Hill is one. Summary. — Elongated ridges of till, usually in clusters, are called drumlins. Tliey vary greatly in shape and size, the most perfect having the oval shape of a half egg. 114. Glacial Erosion. — In a glaciated country wherever the rock is uncovered, its surface is likely to be polished, scratched, and grooved (Fig. 289). In eastern United States the striae point toward Labrador. Strise and erratics found on high mountains prove that the ice was thick enough to override the tops of mountains even a mile in height. The northern slopes of hills and mountains over which the ice moved are often rounded by ice erosion ; and ledges have the smoothed and rounded form of the roclies moutonnees fp. 142). Pebbles and bowlders in the till are also smoothed and scratched (Fig. 291). It is evident that much work of erosion was done as the ice sheet moved onward, pressing down with enormous weight, and dragging its rock load over the land. It acted like a great rasp or sheet of sandpaper. By this erosion some rock was removed from the hills, but more was worn from those valleys along which the ice moved freely. In this way many north-south valleys were so deepened that their tributaries now enter through hanging valleys (Fig. 293) ; and the same is true of bays and fiords on the coasts of Maine, Labrador, Alaska, and Norway. By such erosion the valleys of the larger Finger Lakes of central New York (Cayuga and Seneca) were deepened ; and part of the depth of Lake Ontario, and others of the Great Lakes, is also due to ice erosion. During this erosion, rock basins, in which lakes and ponds now stand, were scoured out. Thus the land surface was decidedly modified by erosion. Summary. — That the ice sheet did much erosion y is proved by striated pebbles, bowlders, and ledges ; by rounded north slopes ; by roches moutonyiees ; by hanging valleys ; and by rock basins. The ice sheet acted like a great rasp, planing doivn the surface, especially in valleys through luhich it freely moved. country by filling the valleys, as in the prairie region of the Central States. 115. Effects of the Ice Sheet. — In some places the surface was roughened by the deposit of drumlins, eskers, kames, and moraines. Elsewhere the drift has smoothed the surface by making thicker deposits in the valleys than on the hills. This smoothing reaches its extreme in the prairie region of the Central States, where, in some cases, drift in the valleys has a depth of 500 feet. Tlie level surface and fertile soil of the prairie are therefore due to the glacier (Fig. 292). Throughout the glacial belt the drift soil shows many variations; for example, stony, clayey, sandy, gravelley, level, irregular. On a single farm there may be several kinds of soil. Sometimes this is better than the soil of rock decay that existed before the ice sheet came ; in other cases a barren, sandy, gravelly, or bowldery soil (Fig. 284) has been left in place of a fertile residual soil. Usually the glacial soil is a strong one, because it consists of ground-up rock fragments, which are slowly decaying and releasing plant food. so much manufacturing. Fig. 295. — Compare this map with one of the present drainage. For purpose of comparison, make a sketch map of the present drainage from a geography map. In some cases streams have been turned into other river systems. Before the glacial period the upper Ohio, above Wheeling (Fig. 295), flowed into Lake Erie valley through the Grand River ; and the Allegheny is made by the union of two streams, one of which entered the Lake Erie valley west of Erie, Pa., the other east of Dunkirk, N.Y. The present St. Lawrence system has also been made by the union of several independent parts. it would, in thousands of cases, be found different from the present. Some of these changes have been of great importance ; for example, how different would have been the history of Pittsburg if there had been a waterway to the north (Fig. 295) instead of to the southwest ! How different would have been the history of Cincinnati if the Ohio flowed past it as a small stream without its great tributaries, the Allegheny and Monongahela ! And what a contrast there would be where Buffalo and the other lake cities stand if glacial changes had not united streams and caused lake? in the valleys of the St. Lawrence system ! Of the tens of thousands of lakes in the glacial region, the great majority are due to some interference of drift deposits with drainage (Figs. 297-300). This is true of the small ponds and lakes, of which there are said to be 10,000 in Minnesota alone ; and it is true of the many large lakes. Even the basins of the Great Lakes, caused in part by glacial erosion and changes in level of the land, owe a portion of their depth to dams of glacial drift. What an important difference it would make in the cities and industries of northern United States if glacial action had not caused the lakes which dot the surface! Summary. — TJie ice sheet caused many changes, making some regions rougher than before, others smoother ; it chayiged the soil, causing it to differ greatly from place to place ; by turniiig streams aside, it led to the formation of many gorges and waterfalls ; it has even turned streams into other systems ; and it has made thousands of lakes, great and small. Topical Outline. — 99. Valley Glaciers. — (a) Formation: snow field ; movement of snow ; neve ; formation of ice ; extension of ice tongue, (h) Movement: nature; rate; glacial erosion . (c) Moraines: lateral ; medial ; crevasses; ice falls; movement of materials to bottom; ground moraine ; terminal moraine, (c?) Wash deposits : source of water ; of sediment ; rock flour ; nature of deposit. 102. Former Extension of Valley Glaciers. — (a) Instances, (b) Evidence: erratics; striae; moraines; till; wash deposits, (c) Ice erosion : roches moutonn^es ; rock basins; cirques; hanging valleys. 103. The Greenland Ice Sheet. — (a) General condition : topography ; coast ; valley glaciers ; area of ice ; meaning of ice sheet. (6) The ice sheet : interior condition ; outward motion ; nunataks ; valley tongues ; size; movement; icebergs, (c) Rock materials: on the surface; at the base ; erosion ; deposits at margin, (d) Former extension. 106. Former Ice Sheets in Europe and America. — (a) Extent : Euroj)e ; America; continental glaciers, ^(b) Proofs: striae; erratics; ice erosion ; glacial deposits ; glacial drift, (c) Agassiz's explanation. 115. Effects of the Ice Sheet. — (a) On the land surface : irregular surfaces ; smooth surfaces; prairies, (b) On soil : differences; strength of glacial soils, (c) On streams: formation of gorges and falls; instances; effect on manufacturing ; complete turning aside of streams ; importance of this, (d) On lakes: cause; numbers; Great Lakes; importance. Questions. —99. What is the snow field? What is the nature and origin of the n6v6 ? What is a valley glacier ? Why does it extend down the valley? How does the ice move ? What is happening at its bottom? What are lateral moraines ? Medial moraines ? Crevasses ? Ice falls ? What descends through the crevasses? What is the ground moraine? Terminal moraine ? Account for the wa§h deposits. 102. Where did valley glaciers formerly exist ? What are erratics ? What is till? Why is it nnstratified? What work of erosion did ancient glaciers perform? What are roches moutonn^es? Rock basins? Hanging valleys ? State the evidences of former valley glaciers. 103. What is the condition of Greenland? What is an ice sheet? What is the condition in the interior? How does the ice sheet move? What is the condition at its margin? How are rock materials carried? What deposits are being made ? State the evidence of former extension. 106. Where were there former great ice sheets? What evidence is there of former glaciation ? Why are the deposits called glacial drift ? Who proposed the theory of the Glacial Period ? Why ? 110. What changes occurred as the ice melted from the Great Lakes? AVhat deposits were made ? AVhat evidence is there of change in level of the land? State the past and possible future effects. 11.5. What effects had the ice sheet on surface features of the land? On soil? On stream courses? Give instances of streams turned into other systems. What effect had the ice on lakes? Suggestions. — (1) Cut out a square block of ice and float it m water. Measure it to. see what proportion is above water. Place the same block in salt water and measure the proportion above water. (2) In a box, the end of which can be removed, place thin layers of snow interspersed with sheets of mixed gravel, sand, and clay, placing a much greater amount in the part from which the end of the box is to be removed. Compact it as tightly as possible, then allow it to freeze. Remove tlie end of the box, allow the ice to melt, and watch ♦^^he result. Does a moraiue-bke accumulation form at the front? DiMi^- the surface of the ice eventually become covered with sand? A large number of glacial phenomena can be imitated by a little ingenuity, — for example, cutting crevasses, boring a tunnel at the bottom of the ice, and sprinkling the ice surface to supply water. The stream that issues from the tunnel may be made to build wash deposits on a moderate slope; or to build sand plains in temporary lakes along the ice margin, etc. (3) Imitate moraine topography by dumping small pailfuls of sand in piles close together. (4) Is your home in the glacial belt? If so, what effects of the glacier can you find in the neighborhood, either by a study of the typographic map or, better still, on a field excursion? Is the soil till or stratified drift? To answer this question look for cuts and study them carefully. If till, look for scratched stones. If stratified, why are the pebbles rounded and the scratches gone? Look for glacial scratches on recently uncovered exposures of bed rock. What is their direction? Are the bowlders and pebbles all of the same kind as the bed rock? Do you know if any of them could have come from ledges in the direction in which the strife point? Can you find moraines, kames, eskers, or drumlins? If so, study them, — their form and the nature of the material. Reference Books. — Russell, Glaciers of Xorlii America, Ginn & Co., Hostou, 1897, !$1.75; '1'arr, Phijsical Geographij of Ne/v York State, Chapters IV and VIII, Macmillan Co., X.Y., 1902, f$:j.5(); WhiCxHT, Ice Age in North America, Appleton & Co., N.Y., 4tli ed., 1902, $r).()0 ; Man and the Glacial Period, Appleton & Co., N.Y., 1892, $1.7.5; Bonney, Ice Work, Past and Present, Appleton & Co., N.Y., 1896. ^\ 50; Geikie, The Great Ice Age, Appleton & Co., N.Y., 3d ed., 1891, !&7.50; TYNDAi.r,, Glaciers of the Alps, I.,oiigmans, (jreen & Co., N.Y., 1896, iS2..50; Sua leu and Davis, 'V/r/c/er.s, Houghton, Mifflin & Co., Boston, 1881, flO; Lubijock, The Scenerij of Switzerland, Macmillan Co., N.Y., 1898, \|150; SallsBURY, Glacial Geology, Vol. V, 1902, New Jersey Geological Snrvey, Trenton, N.J. ; Nansen, First Crossing of Greenland, Longmans, (rreen & Co., N.Y., 1892, $1.25; Peary, Northward over the Great he, P. A. Stokes, N.Y., 1898, »'$6.50; Dryer, Studies in Indiana Geographg, Inland Publishing Co., Terre Haute, Ind., 1897, $1.25. U. S. Geological Survey as follows: Russell, Existing Glaciers of United States, 5th Annual, p. 309; Mcdaspina Glacier, 13th Annual, p. 7; Reid, Muir Glacier, 16th Annual, p. 421; Chamberlin, Terminal Moraine, 3d Annual, p. 295; StricB,1th. Annual, p. 155; Leverett, Illinois Glacial Lobe, Monograph XXXVIII; Glacial Formations, etc., of the Erie and Ohio Basins, Monograph XLI ; Stone, Glacial Gravels of Maine, Monograph XXXIV; Cpham, Glacial Lake Agassiz, Monograph X.XV, LAKES. 116. Origin of Lake Basins. — A lake is a body of water occupying a basin or depression on the surface of the land. Lakes form parts of river systems, but their basins are not oasins are formed by dams across stream valleys. Most of the leading causes for lake basins have already been stated. (See pages 55, 60, 6.3, 67, 76, 78, 95, 97, 103, 121, 123, 130, 131, 142, 148, 149, 154, and 156.) Make a list of these causes. From it you will see that there are various reasons why Fig. 296. — Two diagrams of the same valley. In the lower figure a lake has been formed by downfolding, or warping, of its bottom. LAKES AND SWAMPS. dams may be made across stream valleys, changing them to lake basins. By far the most important of these causes are the glacial dams which have so recently interfered with the drainage of large areas of Europe and America. Many lakes, such as the Great Lakes (p. 156), are due to a combination of two or more causes. There are still other causes than those already stated for lakes and ponds. For example, beavers build dams of wood and mud across* streams to make swamps and ponds for their homes and feeding grounds. Man is now one of the most important agents in the making of lake basins. To supply water for power, for the use of cities, and for irrigation, men are making ponds and lakes in many parts of the earth. Summary. — Lake basins, though parts of I'iver systems, are not generally formed by the rivers, but by some interference ivith drainage, usually by some kind of dam. Man is now making ma7iy lakes. 117. Size and Form of Lakes. — There is every gradation, from mere ponds to the largest of lakes. Some are very shallow ; others have great depth ; in many the bottom is below sea level ; and even the surface of some, like Dead Sea, is below sea level. The following tables give some facts regarding the size and depth of certain large lakes. The great majority of lakes are longer in one aixection than in others. The explanation of this fact i.s that they occupy parts of river valleys, and, therefore, hav6 a long axis in the direction of the valley. If the water risen into tributary valleys, the outline of the lake becomes irregular, as in tlie case of Lake Champlain. Because the basin which they occupy is round, some lakes are nearly circular. This is true, for instance, of crater lakes (Figs. 215, 216, 225), sinkhole lakes (p. 60), and kettle-hole ponds (Fig- 294). Deltas built out into lakes help to make them irregular ; .md, on the projecting deltas, towns and villages are often ulaced (Figs. 107, 297). Deltas at the head of lakes, where the inlet streams enter, shorten the lake. On the other hand, waves tend to straighten lake shores by cutting back headlands and building beaches, which often shut in small bays, transformin>r them to ponds (Fig. 370). Fig. 301. — A map sliovviug the extent of ancient Lake Bonneville, as indicated' by the beaches and other shore lines on the surrounding luouutaiu slopes. The present Great Salt Lake is shown ocoupying a part of the desert plain on the sUe of this extiuct lake. Summary. — Lakes vary greatly in size, depth, and form ; but most lakes are long, because they occupy parts of river valleys. Deltas on the sides of lakes make them irregular; but ivaves tend to straighten the shores. 118. Salt Lakes. — Tlie largest lake in tlie world, the Caspian Sea, is salt. It receives an enormous inflow of fresh water from the Volga and other rivers ; but in that dry clima^^\ evaporation is so rapid that the water does not fill the basin and overflow. Its surface is about 85 feet below sea level. Dead Sea, whose surface is 1300 feet below sea level, is one of the saltest lakes in the world, being nearly a quarter salt, although entered by tlie fresh-water Jordan. Great Salt Lake is about one fifth sp.lt ; and this amount so increases the density of the water that a man cannot sink in it. Where the water has risen over the low plain surrounding the lake, and evaporated, the ground is incrusted with salt ; and, by leading the water into shallow basins, and allowing it to evaporate, salt for use is obtained. The explanation of salt lakes in dry climates is as follows : Streams carry salt, gypsum, carbonate of lime, and other mineral substances in solution (p. 51). Where lakes have outflows, these substances are in part borne away by the outlets ; but in arid climates evaporation is so great that the lakes cannot rise and overflow the rims of their basins. Therefore, while the water is removed by evaporation, the mineral substances are left, and the water grows gradually Salter. If evaporation continues long enough, there will be so much salt that some of it must be deposited on the bottom. Great Salt Lake is not yet salt enough for this ; but carbonate of lime is being deposited. In the Great Salt Lake basin there are wonderfully perfect deltas, beaches, and wave-cut cliffs on the mountain sides, hundreds of feet above the valley bottom. By tracing these shore lines it is found that a great fresh-water lake, now named Lake Bonneville (Fig. 301), formerly filled this basin, overflowing into the Columbia. Its area was as great as that of Lake Huron, and, on the site of Salt Lake City (Fig. 133), the water was over 1000 feet deep. Great Salt Lake is the f.hrunken descendant of Lake Bonneville, occupying a shallow depression on the lakebottom plain. In other arid regions there is evidence of former periods of greater moisture. Summary. — Salt lakes, common in arid regions, are due to the fact that evaporation prevents the water from rising to a point of overflow, and, by removing the ivater, leaves behind salt and other dissolved mineral substances. Elevated shore lines aroimd the basin of Great Salt Lake prove former periods of greater moisture, 119. Life History of Lakes. — Some lakes disappear by the sudden removal of the dam, as in the case of glacial lakes (p. 149); others, like Lake Bonneville, disappear by evaporation. But most lakes have a different life history, being destroyed partly by filling, partly by cutting down at the outlet. Cutting at the outlet is usually slight, because the sediment has been filtered out in the quiet lake water, thus robbing the outlet stream of tools for erosion. This is illustrated by Niagara River, which, though emerging from Lake Erie with great volume, has been able to do little more than cut a shallow valley in the loose glacial drift (Fig. 483). Every stream that enters a lake is bringing to it sediment which is helping to fill the basin ; and the waves, winds, and rain wash add to this sediment supply. The finer rock fragments are carried out into the lake and strewn over its bottom, while the coarsest fragments are deposited near the shore, especially opposite the stream mouths, building deltas. (Figs. 107, 293, 297.) As soon as part of a lake becomes shallow enough, vegetation commences to grow in the quiet water (Figs. 303, 306). The death of these plants — including lilies, reeds. CH»e, and spliagnum moss — supplies further material for lake filling. Gradually the lake is replaced by a swampy plain (Fig. 304), the upper layers of which are made of vegetable remains. Over this swampy plain the streams meander, gradually building it higher by flood deposits until it becomes a dry-land plain. During its existence, a lake acts as a temporary base level, below which the incoming streams cannot cut. But when a lake is filled, the outlet stream, being no longer robbed of its sediment, is able to cut more rapidly ; and, as the outlet stream deepens its valley, opportunity is given for the streams on the lake plain to cut valleys. Then the sediment with which the lake basin has been filled is slowly removed. In the glacial belt there are many illustrations of partly or completely filled lakes and ponds ; and among mountains every gradation in lake destruction is found, even to the point where all lake sediment has been removed. Summary. — Lakes are normally removed by combined cutting at the outlet and filling loith sediment ; but doivn-cutting at the outlet is usually slight because the outfioiving streams have little sediment. Plant growth, and the floods of streams that floiv over the swampy 2)lai7i, accomplish the final stage. Wlien filling is complete, the streams are able to cut into these lake beds and remove them. 120. Importance of Lakes. — Lakes are highly important as resorts for people in search of rest and recreation. The beautiful scenery, cool climate, boating, bathing, and fishing attract thousands of people each summer to the Great Lakes, Lake George, Lake Champlain, and the lakes of the Adirondacks, the Catskills, and New England. Lakes have a decided influence on climate. In summer the water warms less rapidly than the land, and this cools the air over the lakes. In winter, on the other hand, when the land is frozen and snow covered, deep lakes are open and the temperature is, therefore, above freezing point. This open water acts like a great stove, raising the temperature of the air, which winds carry to the neighboring land. The lake water warms so slowly in spring that its presence chills the land near by and retards the buds of plants. It also helps to prevent late spring frosts. This is very important to. delicate plants, like some of the fruits which are greatly injured by frosts late in spring after the buds have appeared. The water, warmed in summer, also tends to prevent early autumn frosts, and thus the growing season for delicate plants is prolonged. For these reasons lake shores are often the seat of important fruit-raising industries. This is well illustrated on the shores of the G-reat Lakes. One of the best vineyard regions of the United States is along the south shore of Lake Erie; and the peninsula of Ontario, between Lakes Erie, Ontario, and Huron, has so moderate a climate that peaches and tobacco are grown. A similar influence is felt all along the Great Lakes. Lakes are an important source of food fish. They are also a source of ice, which may be stored for use in summer. To freeze shallow lakes does not require great cold ; but large, deep lakes rarely freeze. The reason for this fact is that, until a temperature of 39° is reached, fresh water becomes steadily heavier and sinks. It is, therefore, necessary to lower the temperature o1 the entire lake to 39° before the surface freezes. The settling of cold water in winter gives to the bottom of deep lakes a temperature of 39° throughout the year. Lakes are also of great value in navigation. In early days the Great Lakes were of the highest service as pathways for the explorers of the wilderness ; to-day they are thronged with ships going in all directions. By this lake navigation and commerce the location of several great cities has been determined — Duluth, Milwaukee, Chicago, Detroit, Toledo, Cleveland, Buffalo, Toronto, and others (p. 313). The building of railways into the interio of Africa is now opening up the great African lakes to navigation. They have already been important factors in the development of tropical Africa, and were traversed by steamboats even at the time when it was necessary for all the machinery to be carried to them on the backs of men. As storage basins and regulators of water supply, lakes serve still another important purpose. While the volume of such rivers as the Mississippi varies with the rainfall, the lakefed Niagara and St. Lawrence maintain a very uniform flow. It is because they store large quantities of water for steady supply that lakes and ponds are so useful for city water supply, for factories, and for irrigation. The fact that sediment settles in lakes makes them of further value in supplying clear drinking water, even though entered by very muddy streams. Indeed, ponds are often made part of a city water supply for this very purpose of removing sediment. The drying up of salt lakes leaves beds of salt, some of which are found on the surface of arid lands, as in western United States ; others are buried deep in the earth. Dried-up salt lakes also supply other mineral substances, one of the most important being gypsum, which is used for plaster of paris, land fertilizer, and the " chalk " of crayons. Summary. — Lakes are important as resorts ; they have decided influence on the climate of near-hy land ; they are a source of ice ; they supply food fish ; they are very useful for navigatioyi ; they act as storage reservoirs for a steady supply of water, and as settling basins for sediment ; and dried-up salt lakes furnish beds of salt, gypsum, and other mineral substances. SWAMPS. 121. Causes of Swamps. — A swamp is a damp place on the land, not ordinarily covered by standing water. It is caused bv some interference with the run-off of water, such as a gentle slope, or the growth of swamp-loving vegetation. One of the most common causes of swamps is the filling of lakes, forming surfaces so level that swamp plants grow there in abundance. During the stages of lake filling, swamps are formed on deltas, in bays, and, if the lake is small, even along the shores (Figs. 303, 306) ; and, when completely filled, the lake is replaced by a swamp (Fig. 304). In cool, damp, temperate climates, the most important swamp-producing plant is the sphagnum moss, which forms peat bogs. Sphagnum often grows out from the shores of small, shallow ponds, floating on the surface (Fig. 305), and, by the decay of its lower parts, causing a deposit of vegetable muck on the bottom. Eventually the sphagnum may reach entirely across a pond, with growing plants above and a thick, liquid mass of decaying vegetation below. It is then called a quaking hog (Fig. 305), because it trembles, or quakes, under the foot. If one sinks into the muck below, escape is impossible. Very perfect remains of extinct animals, and even of men, have been found in the peat bogs of Ireland, the decaying vegetation forming preserving acids which interfere with decav. Fig. 305. — To show the growth of sphagnum moss out from the shore, forming a quaking bog. In time the moss from the sides will meet, completely inclosing the pond, and, by its decay, covering the entire bottom with muck. Swampy or boggy places are common on hillsides where springs appear, encouraging the growth of sphagnum and other swamp plants. Sphagnum holds water like a sponge, and is thus able to grow some distance from the spring ; in fact, it may even climb the hillside, making a climbing bog. In the damp climate of Ireland, climbing bogs sometimes become so heavy with water that they slide down the hillside, becoming " bursting bogs," by whicli both life and property have been destroyed. The Arctic tundra, in winter a frozen, snow-covered desert, in summer becomes a vast swamp, wherever there is soil. The reason for this is that the melting frost makes the ground wet, as it does in all cold climates in spring. Every rain makes the tundra more swampy, partly because the frost prevents the water from soaking into the ground, and partly because it helps the frost to melt. In this swampy land mosquitoes develop in such numbers as to become a great pest. The overflow of riveivs causes swamps in low places on floodplains, especially on the low ground just belv.nd the natural levees. These swamps are unfit ^o^ v dtivation and are occupied by dense forests of cypress, black gum, and other swamp-loving trees (Fig. 308). Swamps are also found along the lower courses of rivers, where the river water is backed up by the tide and caused to overflow low Level coastal plains (p. 72) often have so gentle a sIojdp that the water cannot run off; and the drainage is further interfered with by the rank growth of vegetation which the water encourages. Such swamps are found on the coastal plain of Texas and in Florida (Figs. 78, 79), especially in the Everglades region. The famous Dismal Swamp on the coastal plain of Virginia and North Carolina is another illustration (Fig. 307). By clearing off the vegetation, and cutting ditches for the water to run through, parts of Dismal Swamp have been drained. Naturally there are few swamps in arid lands ; but some are found near springs and on the river floodplains. There are also marshy places — alkali flats and salines (p. 87) — in which only a few species of plants can grow. At times of flood they may become shallow, muddy lakes, called play as; but, at otlier seasons, evaporation changes them to hardened mud, crusted over with alkali and salt. When wet, the deep, sticky mud often makes them quite impassable. Summary. — Sicamps are caused during the ^fiUing of lakes, one form of such swa7nps bnug the peat hog, formed by the growth of sphagnum moss. Spyhagyiuni also makes swampy places around springs, and climhi)ig bogs on hillsides. Hie melting of frost in su7nmer catises the Arctic tundra to be swampy wherever there is soil. Swamps also occur along rivers and on level coastal p>l(ii^is. In arid lands, where evaporation causes a deposit of salt or alkali, there are swampy tracts^ called alkali f^ats and salineb: > 122. Effects of Swamps. — The dampness of swamps makes them unhealthful; and malaria, transmitted b}^ mosquitoes which breed in the water, prevails in many swamp regions. In tropical regions, as along the narrow coastal plain of the central African coast, and in Central America, fever is so common that white men suffer even in crossing the level, damp iowland. Because of malaria, parts of Italy have become quite deserted ; and some of the river bottoms and rice swamps of the South have been left to the negroes, who suffer little from the unhealthful climate. Swampy conditions unfit land for most purposes except rice production; but, when drained, the rich, black soil is very productive. For this reason, as well as for the sake of health, swamp lands are being drained, where possible. This has been done much more extensively in Europe than in America, where land is less valuable. The most extensive drainage has been carried on in the Netherlands, where the low, swampy delta of the Rhine, and even part of the shallow sea bottom, have been protected by dikes, and drained by pumping. About one half of the Netherlands is reclaimed land, a large part of it being below sea level. The salines of arid lands have valuable stores of salt ; and the peat bogs of cool temperate climates are important sources of fuel. Coal and wood are so abundant in America that this source of fuel is scarcely touched ; but in northern Europe it is a very important fuel, being cut out with spades (Fig. 309) and dried and stored for winter. Coal beds are similar swamp deposits, made ages ago, and covered and preserved beneath thick beds of sediment. The swamp deposits of Florida would, if covered with layers of sediment, slowly change to coal. Summary. — Swamps are unhealthful, being a source of malaria ; they are of little value, unless drained ; hut the salines supply salt, and the peat bogs fuel. Coal is made of swamp deposits, slowly ' changed to mineral and preserved beneath beds of sediment. Topical Outline. — 116. Origin of Lake Basins. — Definition; im. possibility of formation of large basins by rivers ; causes for lakes ; most important cause ; combination of causes ; effect of beavers ; of man. 118. Salt Lakes. — (a) Instances: Caspian Sea; Dead Sea; Great Salt Lake. (&) Cause : source of salt ; failure to overflow ; increasing saltness. (c) Former moist periods : shore lines ; Lake Bonneville. 119. Life History of Lakes. — Exceptional causes for removal; cutting at outlet ; slight importance ; sources of sediment ; places of deposit ; effect of vegetation ; change to dry land; removal of lake beds. 120. Importance of Lakes. — (a) Summer resorts: reason; instances. (b) Climate : summer influence ; winter ; spring ; autumn ; effect on vegetation; illustrations. (c) Food fish. (d) Freezing: ice; reason why deep lakes do not freeze, (e) Navigation : Great Lakes ; cities ; African lakes. (/) "Water supply : effect on floods ; storage of water ; settling of sediment, (g) Dried-up salt lakes : salt; gypsum. 121. Causes of Swamps. — (a) Definition, (b) Lake swamps; filled lakes; lake shore swamps, (c) Peat bogs: sphagnum; quaking bogs; animal remains, (d) Hillside swamps : springs ; climbing bogs ; bursting bogs, (e) Tundra swamps : in winter ; in summer. (/) River swamps : floodplains ; In lower course. (g) Coastal plain swamps : cause; illustrations; drainage. (A) Arid land swamps: scarcity; alkali flats ; salines ; playa lakes, (i) Seashore swamps. 120. Why are lakes favorite summer resorts? How does the lake water influence climate? What effect has this on vegetation? Why do not deep lakes freeze? Give illustrations of the value of lakes in navigation. What effect have lakes on water supply? What important mineral substances are supplied from dried-up salt lakes ? 121. What is a swamp? In what ways are swamps associated witl: lakes? What are peat bogs? Quaking bogs? Climbing bogs? Whyare tundras swampy in summer ? Where near rivers do swamps occur ? Why are swamps common on coastal plains? Give illustrations. What are alkali flats and salines ? Playas ? 122. What effect have swamps on health? What effect have swamps on agriculture? How may they be made valuable? What fuel is supplied from swamps? What is the origin of coal? Suggestions. — (1) Make a valley in clay and pour water into it. It is a stream valley. Place a dam across it and make a miniature lake. What is its shape? Make one or two tributary valleys into which the water rises. What is the shape then ? Wash sediment into the lake by sprinkling the sides with a watering pot. Notice the growth of deltas. The lake may even be filled. (2) In a deep jar of water, take the temperature at the top and bottom. Pound up ice and put it into the jar, and when it has all melted, again take the temperature at the top and the bottom. Why has the bottom water this temperature? Continue putting in ice until the temperature at the surface is 36°. What is the tern perature at the bottom then ? (3) Place a large dish of warm water in a cold room. Does the temperature of the air change as a thermometer is brought near the water ? Try the same experiment with a large dish of ice-cold water in a warm room. (4) If your home is near a lake, study it. Can you find out what caused it? Does the outlet stream flow in a deep or shallow valley? Are there any deltas? Where? Any signs of filling by wave action? Are there any swamps? What kinds of plants grow on the shallow lake bottom and shore? (5) Are there any swamps near your home ? What is their cause? Is it believed that they are unhealthful? Are any of them partly or wholly drained? How was it done ? What effect has the draining had ? (6) Make three surf aces of clay : (1) a steep slope, (2) a plain, (3) a plain with vegetation (made by putting pieces of grass in it). Sprinkle with water. Which remains wet longest? Why? Which dries first? Reference Books. — Russell, Lakes of North America, Ginn & Co., Boston, 1895, $1.50; Tarr, Physical Geography of Neio York 6^to^e, Chapter VI, Macmillan Co., N.Y., 1902, $3.50; Gilbert, Lake Bonneville, Monograph I, U. S. Geological Survey; Lake Bonneville, 2d Annual, U. S. Geological Survey, p. 169; Russell, Present and Extinct Lakes of Nevada, National Geographical Monographs, American Book Co., New York, 1895, $2.50; Lake Lahonton, 3d Annual, U. S. Geological Survey, p. 195 ; Lake Lahonton, Monograph XI, U. S. Geological Survey ; Mono Lake Region, 8th Annual, U. S. Geological Survey, p. 267. THE OCEAN. 123. Importance of the Ocean. — We have already learned (p. 15) that the ocean is in many ways of importance to man. It supplies vapor for rain, and moderates the climate of the lands, it is a source of food and other products that the ocean is to determine its deptli and tlie nature of its bottom in order to discover proper lines for submarine cables. These cables are so important in commerce and war that lines now cross the oceans in various directions. To determine the depth, use is made of a sounding machine "which lowers an iron weiglit, usually a cannon ball, to the bottom. This heavy weight is not drawn back to the surface, but is automatically released when botj^om is struck (Fig. 310). A sample of the ocean-bottom water is brought up in a metal tube, or water bottle ( T, Fig. 310), which remains open on the way down, but closes when drawn up. A sample of the ocean-bottom mud clings to soap or tallow placed on the bottom of the water bottle ; and the temperature is determined by thermometers attached at and the temperature eoRMAv CO.. N.Y. of the water at variFiG. 311. — Apparatus used by the Challenger in OUS points are all (? is a weight, and B, C, B, E, and F obtained. ploring expeditions also make a study of the animal life of the ocean bottom. Specimens of these animals are obtained by means of a deep-sea dredge, or trawl (Fig. 312), which consists of an iron frame several feet in length with a long bag net attached. This is dragged over the ocean bottom (Fig. 311), animals in its path being scooped up by the frame and gathered in the bag. Many v(rf^}vd creatures arft thus obtained. Over 3000 Fig. 314. — The depths of the Atlantic in fathoms (a fathom is six feet). The mid-Atlantic ridge is called Dolphin, Connecting, and Challenger plateaus. Note the continental shelves, dotted. FiQ. 315. — Section to show, in diagram, the conditions of temperature and depth in the Atlantic. Ocean depth and width of continental shelf greatly exaggerated. The raised portion in the center represents the mid-Atlantic ridgfr 5i»ammary. — For a study of the ocean, or oceanography, there have been numerous government exploring expeditions, one of whose objects has been to determine the best lines for cables. In the study of the ocean bottom the depth, nature of the water, nature of the bottom, temperature, and kind of animal life are usually determined. 125. Ocean Basins. — Exploration has shown that the ocean bottoms are mainly vast submarine plains (Figs. 313, 316). Beyond the continental slopes (p. 22) almost the entire ocean floor is a sunk below the rest, forming a deep (Fig. 314) ; and here and there volcanic peaks or mountain ridges rise from the ocean floor (Fig. 313), sometimes reaching above the surface. But these elevations and depressions are only exceptions to the general levelness. The Blake deep, not far from Porto Rico, is the deepest known point in the Atlantic Ocean, 27,360 feet (Fig. 313). There are a number of volcanic peaks in the Atlantic, such as the Bermudas, the Azores, the Canaries, Cape Verde Islands, and St. Helena. In the mid-Atlantic there is a low, irregular elevation, or a series of submarine plateaus (Fig. 314), sometimes called the mid-Atlantic ridge (Fig. 315). There are deeps on both sides of it. This upraised portion extends the whole length of the Atlantic, usually several thousand feet beneath the surface. There are hundreds of volcanic peaks in the open Indian and Pacific oceans (Fig. 313), usually in chains along the crests of submarine mountain uplifts, — for example, the Hawaiian chain, and the Ladrone chain, of which Guam is one peak. The deepest known point in any ocean, 31,600 feet, is the Challenger deep, near Guam. The Aldrich deep, near New Zealand, is 30,930 feet; and the Tuscarora deep, east of Japan, 27^930 feet. Little is known about the Arctic and Southern oceans; but Nansen found a depth of over 12,000 feet in the Arctic, and parts of the Southern Ocean are also known to be very deep. Summary. — Beyond the continental slope is a vast expanse of plain, covering about tico thirds of the earth's surface. There are occasional deeps sunk beloio its general level, and volcanic cones and mountain ridges rising above it. 126. Deposits on the Ocean Bottom. — (A) Rock Frayments. — The wind, rain, rivers, and waves drag fragments from the land into the sea. Most of this sediment settles in the quiet water near the coast ; but currents drift some of the liner particles out to sea, even to the edge of the continental shelf. This sediment fills depressions and tends to smooth over the irregularities of the continental shelf ; and, by its accumulation, it makes beds of sedimentary rock, coarsest near the coast (p. 32). Remains of ocean animals also accumulate on the bottom and add to the deposit of, sediment, being bution of animal remains exceeds that of rock waste. More than a third of the ocean bottom is covered with an ooze, composed mainly of animal and plant remains. This deposit contains a small percentage of rock fragments, especially pieces of volcanic ash and pumice that, on becoming water-logged, have settled to the bottom. The ocean-bottom ooze is made partly of organisms that live on the bottom, but mainly of the shells of microscopic organisms that live in vast numbers in the surface waters and, on surface, greatly magnified. Summary. — Far from land, tvJiere there is Utile rock waste, the ocean bottom is covered with glohigerina ana other oozes, made largely of the remains of organisms, mostly microscoinc surface forms. (C) Bed Olay. — The shells that sink to make globigerina ooze are composed of carbonate of lime, but contain a very small percentage of other substances, such as iron and silica. In the very deep ocean water (12,000 to 15,000 feet or more)> which contains much carbon dioxide, these limy shells are dissolved ; but the iron, silica, etc., are not so readily soluble, and they pass on to the bottom forming a clay, colored red by iron oxide. More than a third of the ocean bottom is covered with this red clay, whose rate of deposit must be very slow since it is formed of the very small insoluble portion of shells that are themselves microscopic. Other facts further prove that the red clay is formed with wonderful slowness. Scattered through it are fragments of pumice, bits of meteoric iron, the teeth of sharks, and the ear bones of whales. There are not many whales or sharks in one place, nor are many meteorites falling. If the red clay were not accumulating very slowly, these objects would be so deeply covered that a small dredge would rarely find any 5 yet deep-sea dredging often brings them to the surface. Summary. — Bed day covers the deeper j^cirts of the ocean bottom ; that is, over one third of the entire ocean floor. It is a very sloicly forming deposit, made of the insoluble remnants of microscopic shells that have been dissolved in the deep-sea water. 127. Land and Ocean-bottom Topography. — There are three important reasons why the ocean bottom is far more regular than the land surface (p. 21). (1) While mpuntain folding and volcanic action cause irregularities both on land and ocean bottom, they are less important in the sea than on the land. organisms to the bottom, tend to smooth the sea floor. Because of these facts, if a smooth sea-bottom plain is raised into the air, it is soon carved by erosion into a series of hills and valleys; but if a 1 irregular, hilly land is sunk beneath the sea, it is soon smoothed over by a blanket of sediment (p. 72). There is a striking difference between the widespread smoothness of ocean-bottom plains and the pleasing irregularity of the lands. Summary. — The ocean bottom is far smoother than the lands because of (1) less mountain folding and volcanic action ; (2) absence of erosion ; and (3) widespread deposit of sediment, 128. Surface of the Sea. — Elevations on the land are measured from sea level, by which is meant the approach to a spherical form which the water assumes under the pull of gravity (p. 8). The level of the sea is not perfectly in accord with the spherical form of the earth ; for the curved water surface is distorted a little by the attraction of the continents, slightly raising its level near the coast. Winds and storms (p. 271) cause local disturbances of sea level ; but, as soon as the disturbing cause has passed, gravity draws the water back to its former level. There are two causes which are slowly operating to change the level of the sea. The less important of these is the deposit of sediment, which tends to slowly raise sea level. It would take long periods of time for this to produce a great effect, fcr there is a vast amount of water to be raised. Even if all of North America above sea level were put into the Atlantic, the surface of the oceans would not be raised many feet. The second cause for change in level is movement of the ocean bottoms. There is good reason for believing that, during past ages, the ocean basins have been slowl}^ growing deeper. The effect of such a movement would be to gradually withdraw the waters from the lands. Summary. — Sea level is slightly disturbed by the attraction of the continents ; locally, and for short times, by loinds and storms ; and very sloivly by (1) the deposit of sediment in the oceans and (2) the sinking of the ocean bottom. 129. Composition of Sea Water. — Every one is familiar with the saltness of the sea. Probably salt and other mineral substances were held in solution when the oceans first gathered ; but certainly some is being added every day. The vapor that rises from the ocean does not remove these mineral substances ; but when it falls on the land as rain, it begins to wash more dissolved mineral matter into the sea (p. 51). It would seem, therefore, that the ocean must be growmg steadily Salter. About three and a half per cent of ocean water is dissolved mineral matter, more than three quarters of which is common salt. Magnesium chloride and magnesium, calcium, and potassium sulphates are also present ; and, in very small q-uantities, there are many other substances, even including compounds of gold and silver. If all the salt of the oceans could be removed, it would make a layer about 400 feet thick over the earth. In many places where the climate is dry, salt is obtained by evaporating sea water; and many salt beds, like that in central New York, were formed in past ages by the evaporation of the water in arms of the sea, cut off as the Caspian is to-day. Carbonate of lime, though present in very small quantities, is another important mineral substance in sea water. Many ocean animals, such as corals and shell-fish, use it in the growth of their shells and skeletons. On the death of the animals these have accumulated in beds of limestone which, raised to form land, are now used in building, smelting iron, and making lime. Some air is mixed with all ocean water, being present even on the ocean bottom, where it is brought by slowly moving currents. A few sea animals, sucli as the seals and whales, come to the surface to breathe ; but the great majority vo,(]uire so little oxygen that they are able to obtain what tiiey need from the air that is mixed with the sea water. Without it most of the ocean animals could not live. Summary. — Salt and other mineral substances, incladiug carbonate of lime, of which shells are made, are hei)i(/ constantly -washed from the land into the sea. Air mixed with the wat^r supplies the oxygen which makes most of the ocean life possible. 130. Density and Pressure of Sea Water. — Salt water is heavier, or has a greater density, than fresh water. Calling fresh water 1, the average density of ocean water at the surface is about 1.026. The den^'ity is less than the average in the rainy tropical belt, and paso near the mouths of great rivers, where a large amount of fresh Vv^ater is added. It is greater than the average where there is much evaporation, as in the dry trade-wind belt, and in seas inclosed by warm, arid lands, like the Red and Mediterranean seas. There is an enormous pressure on the bottom of deep oceans. At the depth u; y, mile every square inch bears a weight of over a ten of water, and tlie pressure on the bottom of the Aldrich deep is nearly six tons to every square inch. One might expect that so great a weight of water would crush t.^Q animals on the ocean bottom ; but it produces no more effect on them than does the weight of air (about 15 pounds to the square inch) which our bodies bear. The reason why this great pressure is not felt is that it affects all parts of the body, both within and without. When deep-sea fishes are brought to the surface, however, .and the pressure from outside is reduced, that from within opens cracks in their bodies and often causes their eyes to protrude. Water, unlike air, is not much compressed, even under the great load that wei.^hs down on the bottom lavers. Therefore its density at the bottom does not differ greatly from that at the surface. If it were much compressed, as air is, it might become so dense that objects could not sink through it to the bottom. They would then float around in the dense layers. Summary. — Salt water is denser than fresh water ; hut its density varies somewhat. There is an enormous pressure on the ocean bottom,' hut, since water is not much compressed under pressure, its density is not greatly increased at the hottom. 131 Color and Light. — Sunlight illuminates the upper layers of the sea and reaches to the bottom of shallow water. The beautiful blue of the open ocean is partly due to the reflection of the color of the sky, but chiefly to the same cause which makes the sky blue (p. 233). Sunlight is made of waves of many colors, and in their passage through the water they are separated, or scattered, some of them (the indigo and blue) being reflected back, giving the water its color. Near the shore, where there is more sediment, the green waves are reflected, giving the water its green color. The yellow water near the mouth of the Yellow Eiver of China is colored by the mud that the river brings ; the color of the E-ed Sea is due to minute reddish organisms that float in it. 'No sunlight penetrates to the bottom of the deep sea, which is darker than the darkest night. Having little use for eyes, many of the deep-sea fish are blind ; but others have eyes, and many are brilliantly colored. These eyes and colors are doubtless of use because of the phosphorescent glow, like that of the firefly, which many deep-sea animals emit. Indeed, some of the fish have feelers, phosphorescent on the end, which have been called deep-sea lanterns. Phosphorescence is also emitted by many surface animals, and a boat often leaves behind it a trail of faint phosphorescent light, made by the multitude of animalculse that its passage has disturbed. Summary. — The color of the sea is due to the scattering of the waves that compose white light, and the refection of some of them, such as green, blue, or indigo. No sunlight reaches the ocean bottom, hut some of the animals emit a phosj^horescent glow. 132. Temperature of the Oceans. — The surface layers of ocean water are warmed by the sun. Accordingly, while the waters of the frigid zones are nearly at the freezing point of salt water (28^ or 29°), tropical waters are warmed to 80* or Sd" (Fig. 320). In the inclosed Red Sea, where the Fig. 320. — Ocean-surface temperature. The effect of the land, and of ocean currents, makes the temperature lines of the northern ocean far more irregular than those in the southern hemisphere. On an outline map of the world make a sketch map similar to this. Fig. 322. — A United States government ship (the Wateree) stranded on the land in Chile by an earthquake wave in 1869. The surf line is seen one eighth of a mile beyond the farther ship. BORMAr i CO.. N.Y. Fig. 325. — Temperature on the bottom of the North Atlantic. The band of higher temperature is on the mid- Atlantic ridge (see Fig 3?^,. increase in Jensity, and, therefore, to sink, almost until its freezing point is reached. For this reason ocean-bottom water is much colder than that on the bottom of lakes ; it may, in fact, be as low as 29°, The settling of cold water in the frigid and cold temperate breathing. One of the best proofs of this slow circulation is furnished by such seas as the Gulf of Mexico and the Mediterranean, which are partly shut off from the open ocean. In these seas the decrease in temperature continues down to the level of the barrier, but no lower, because the coldest water that can creep into them is that at the level of the barrier (Fig. 326). Summary. — The temperature of the surface water varies with the climate ; hut settling of cold water, causing a slovj circulation, makes the deep sea everywhere cold. Inclosed sea bottoms have the same tem^perature as that of the op)en ocean at the level of the harrier. y iG. 326. — The temperature in the Atlantic at a depth of 2000 fathoms is 35° ; but in the Gulf of Mexico, at that depth, only 39.5°, which is the temperature at the depth of the barrier (1000 fathoms) over which the water enters the Gulf from the Atlantic. 133. Wind Waves. — Blowing on the surface of a dish of water causes small waves. These are similar to the large waves raised on the ocean by the friction of winds that blow over its surface. The water itself does not advance with the wave, but moves up and down, with a slight forward and backward movement. It is the form of the wave that advances, as a wave may be made to pass through a rope by shaking it vigorously. Therefore a boat, instead of moving is also carried forward and backward a little. Some of the great ocean waves, raised during heavy gales, have a height of from 30 to 50 feet, measured from the top, or crest, to the depression, or trough, between two waves. Then the sta presents a wild sight, as the great waves come down upon a ship, their crests broken and whitened by the fierce wind. The wind mixes much air with the ocean water in the foam and spray of these white crests, or ivJiitecaps (Fig. 341). Such waves, moving at the rate of 40 or 50 miles an hour, sometimes dash over the decks, carrying all loose objects along, and even tearing away massive wood and iron work. Even great ocean steamers are, at times, forced to change their course to avoid the danger of being upset by the approach of these huge waves from one side. To smaller boats they are very dangerous, and many a fishing schooner (Fig. 341) has been sunk by them. The use of oil at sea is now common in violent gales. Dropped on the surface, the oil spreads in all directions ; and, as the oily surface offers less resistance to wind, the waves are much less broken. There is then less danger of waves coming aboard. Waves often appear when no wind is blowing, and even when the sea is smooth and glassy. They were formed in some place where the wind was high, and have traveled far beyond their place of origin. Such waves are known as rollers, or ground swell. Because waves travel so far, no part of the open ocean is ever entirely free from some form of wave or swell. In shallow water the free movement of waves is interfered with by the bottom, the wave grows higher, its front becomes steeper, and it finally topples over (Fig. 327). Tlien tons of water are hurled bodily forward as surf or breakers (Fig. 321), striking the shore with tremendous force. A current, called the undertow (Fig. 327), flows outward along the bottom beneath the incoming breakers. On many wavebeaten coasts the undertow is so strong as to be a source of danger to bathers, who are caught by it and held under water. Some of the rock fragments that are dislodged from cliffs and ground up on the beaches, are moved offshore in the undertow. Others are pushed along the coast (1) by the breaking of waves which reach the coast diagonally, and (2) by the slow windformed surface current (Fig. 327), which moves in the direction the wind is blowing. Summary. — Waves, caused by friction of ivind, are a rising and falling of the wafer, the icave form moving forward, often far beyond the place of origin. They break on the coast with great for e, tearing rocks from the cliffs and grinding them on the beachei,. moving some of the fragments offshore in the undertow, some along the coast 134. Other Waves. — Tap lightly on the bottom of a pan of water, and the water rises in a low dome. An earthquake shock in the ocean produces a similar wave, reaching from the bottom of the sea to the surface. The water may not be raised more than a fraction of an inch, but the disturbance is so deep and affects so much water that, \vhen the wave approaches a neighboring coast, it rises higher and higher. Such a wave may then rise to a height of more than 100 feet, rushing perhaps a mile or more inland, carrying everything before it, and leaving vessels stranded (Fig. 322). Tens of thousands of people have been drowned by a single earthquake wave (p. 119). Fortunately such waves are not common in many parts of the world, though Japan, the East Indies, and the coast of Chile and Peru are subject to them. The waves travel great distances, some from Asia reaching the California coast; but, so far a^^ay, they are too much spread out to be destructive. violent storms at sea. 135. Tides. — Twice each day (more exactly, every 12 hours, 26 minutes) the passage of tidal waves, formed by the attraction of moon and sun (Appendix E), causes the ocean surface to rise and fall (Figs. 328, 329). In the open ocean the difference in height between high and low tide, or the tidal range^ is not over one or two feet ; but, as the tidal wave approaches the coast, its height is increased (Figs. 330, 331) by the effect of the shallowing bottom. In the ocean, and on open coasts, the tide is merely a rise and fall in the water level ; but in bays and estuaries this change in level starts currents, which often move with great velocity. Such currents may m(?"e so rapidly that boats cannot make headway against thci,^ ; indeed, in the Bay of Fundy the tide advances over the mud flats more rapidly than a man can run. From this it is evident why, as the tide rises and falls, it is said to " come in " and ' go out." The rising tide is called ih.^ Jlow^ the falling tide the ehh. The advancing tidal wave is greatly influenced by the form of the coast. Ordinarily the tidal range is between 3 and 10 feet ; but in narrowing, V-shaped bays the range is greatly increased, as in the Bay of Fundy in Nova Scotia and Ungava Bay in northern Labrador, where the tide rises from 30 to 50 feet. On the other hand, where bays broaden out, bag-shaped, the tidal range is greatly diminished. For instance, the Atlantic tide, passing through the Straits of Gibraltar, produces practically no effect on the broad Mediterranean ; but a very small local tide is developed in the Mediterranean itself. This almost complete absence of tide in the Mediterranean was of great impor- Fig. 332. — Range of tide, south of Cape Cod, indicated by figures. In Buzzards Bay it rises 4.1 feet ; in Vineyard Sound, from 1.5 to 3.1; consequently rapid currents, or races, pass through gaps between the islands that separate the two bodies of water. moon the tidal range is greater than during the quarters. Tides with high range are known as spring tides, those with low range, neap tides (Appendix E). The correspondence of spring and neap tides to phases of the moon, and the fact that two complete tides occur every 24 hours, 52 minutes (the period between two moonrises), long ago led the ocean near large cities. Tidal currents aid or impede vessels, according to their direction ; and they sometimes drift vessels from their course, placing them in dangerous positions. Every now and then in foggy weather, when the land cannot be seen, vessels run aground, because the tide has drifted them out of their course. The captains of all large ships carry tide tables and charts to aid them in navigation. One use of these is to tell when the tide is high, for the entrances to many harbors are too shallow to admit large ships at low tide. — Diagram to show time of arrival and height reached by the tides on the two sides of Hell Gate. The currents at Hell Gate are therefore due to two causes . (1) the time of high tide differs on the two sides ; (2) the tidal range differs. Summary. — Every 12 hours, 26 minutes, the ocean surface rises and falls with the passage of a tidal wave. In the open ocean the range is afoot or tivo; along the coast from 3 to 10 feet; in ^ -shaped bays even 30 to 50 feet; but in large bays that broaden, the tide may be destroyed. Along irregular coasts the rise and fall of the tide jamin Franklin studied them and considered them the result of steadily blowing winds. It is now known that there are currents slowly sweeping through each of the oceans (Fig. 338). Differences in temperature of the ocean water account for the settling of water in cold regions and its circulation along the sea bottom (p. 184). But it does not seem an adequate explanation for the surface currents The explanation that best accounts for surface currents is the effect of steadily blowing winds, as suggested by Franklin. By blowing on a pan of water with sawdust floating in it, a drift of water is seen to start; in like manner, winds blowing over lakes or ocean start a similar drift of surface water. Such wind-drift currents continue to move for some time after the wind dies down. portion going into the South Atlantic, the larger into the North Atlantic. This Equatorial Drift is exactly what we would expect to find, for the northeast and southeast trade winds blow steadily day after day, drifting the water westward before them. After dividing on the coast of South America, the drift follows the coast for a while, then slowly swings to the right in the northern hemisphere, and to the left in the southern. ^ 1 A slow current may be called a drift, a more rapid current a stream. 2 This swinging is caused by the effect of the earth's rotation, which deflects all moving bodies, whether wind or water currents, from a straight course. In the northern hemisphere the moving body is turned to the rights in the southern hemisphere to the left. Thus a great, slowly moving eddy is formed in each ocean. Floating seaweed (^Sargassum) accumulates in the center oi the eddy in such abundance that it has been called the GrassT/, or Sargasso^ Sea. Columbus encountered it, and his sailors, not knowing what it was, feared tliat the ships would run aground in it. a part of the Equatorial Drift. A smaller portion of the Gulf Stream water, and some of the North Atlantic Eddy, drifts on into the region of the west winds, which drive it on toward the coast of northern Europe, as the West Whid Drift. Thus water, warmed in the equatorial regioji, tlie Caribbean Sea, and the Gulf of Mexico, is carried to the European coast, and even into the Arctic. There is no similar stream in the South Atlantic, because there are no partly closed seas for the drift to enter. Study the currents of the Pacific to see if the same great eddies are found there. Notice that in the Southern Ocean, where there are no continents to turn the currents, the West Wind Drift extends 'Completely around the globe. Besides these eddies, there are special currents, one of which, the Labrador Current, is of great importance to America. This is a cold current, descending from among the islands of the Arctic along the Labrador, Newfoundland, and New England coasts (Fig. 337). It keeps close to the American shores, being turned to the right by the influence of rotation. Thus, while warm water is drifted toward Europe, cold water flows down the American coast as far south as Cape Cod, where it disappears by settling and mingling with the warm water. Summary. — The surface currents are due to the drifting of water before steadily blowing ivinds. In each ocean there are great eddies, started by the trade winds, which cause an Equatorial Drift toward the west. This, dividing on the continents, follows the coast northward and southward for a ivhile ; then it is turned, by the effect of rotation, to the right in the northern hemisphere and to the left in the southern. TJius an eddy is caused in each ocean, both north and south of the equator. A x>art of the North Equatorial Drift enters the Gulf of Mexico and emerges as the ivarm Gulf Stream, a j)ortion of ichich joins the eddy of the North Atlantic. A portion of the eddy, and of the Gulf Stream, is drifted by the west ivinds to the European coast, and even into the Arctic. In the southern hemisphere the West Wind Drift extends around the earth. The cold Labrador Current sweeps down the American coast from the Arctic, and, being turned to the right, is forced to hug the coast till it sinks. the warm water that is borne into the Arctic by the West Wind Drift, influences the temperature of northern Europe. Its effect was very well shown by Nansen's voyage toward the pole. He started into the Arctic north of Scandinavia, where the warm drift keeps the sea fairly clear of ice in summer (Fig. 338), and was able to push his ship far into the Arctic before he met with impassable ice. Ocean currents aid or retard vessels, according to their direction ; and, in their reckonings, navigators must .make allowance for this influence. Columbus had much difficulty in navigating his small ships among the currents along the northern coast of South America. Currents have other important influences, for example, causing fogs (p. 247), drifting sea ice and icebergs, and bringing oxygen and food for many sea animals (pp. 196, 197). Summary. — Ocean currents affect climate, influence the movemrent of vessels, and are further important in causing fogs, drifting sea ice and icebergs, and bearing oxygen and food for sea animals. ' 138. Ice in the Ocean. — Each winter a large part of the Arctic Ocean is frozen over, often to a depth of 5 or 10 feet. The tidal currents move the ice about, opening cracks or leads, and closing them again with so irresistible a force that the ice is broken and piled up in ridges of pack ice often 50 or 100 feet high. More than one Arctic ship has been crushed like an eggshell between these moving ice fields. Nansen, Abruzzi, and Peary have all tried to reach the North Pole ov^r this frozen sea ; but the many leads, and the irregular surface of the ice packs, have proved such barriers to progress that no one has yet succeeded in reaching the pole. In summer tne ice breaks up, and the fragments drift southward till they melt. Each spring and early summer there is a steady stream of these ice fragments, or icefloes, passing down the Labrador coast in the Labrador current (Fig. 340). Icebergs, discharged from the ice sheets of Greenland and other northern islands (p. 145), also drift in the Arctic waters (Fig. 339). They are huge floating islands of ice, sometimes rising more than 100 feet above the water. Since ice floating m salt water has about seven parts below water to one above, some of these bergs extend 700 or 800 feet beneath the surface. They frequently run aground (Fig. 267), either breaking to pieces by the shock, or remaining aground till melting allows them to float away. So huge are these bergs that, before melting entirely, 'chey may travel 1000 or 2000 miles, even down to the path followed by ocean liners. They are much dreaded, for even the largest, ship may be destroyed by running into one. Far greater icebergs are discharged from the Antarctic ice sheet, some of them rising 500 feet above the water and, consequently, measuring three quarters of a mile from base to top. They have steep sides and flat tops, and are sometimes several miles long. Summary. — Tlie Arctic sea-ice, formed in ivinter, breaks up in summer, some of it drifting southivard in the Labrador current. Huge icebergs, discharged froyn the Greenland ice sheet, drift in the Arctic, and still larger ones in the Antarctic. LIFE IN THE OCEAN. 139. Surface (Pelagic) Life. — The abundance of life in the ocean is marvelous. A pail of water dipped from the surface will contain thousands of individuals, mostly microscopic. These organisms are drifted about by winds and currents, and with them are many larger forms, some merely floating, some swimming. Pieces of floating wood have animals attached to them; and in the floating seaweed, many animals live in little worlds of their own. The minute organisms are the source of food for many larger animals, even for the huge whales. Swimming with its mouth open, the whale strains the water to obtain its food, and thus the largest of animals feeds upon the smallest. Among the many fishes are some, like the mackerel, which are valuable for food supply. For protection, the mackerel and some other fishes swim together in vast numbei's, forming "scbov\s" or "shoals," Summary. — Life is very abundant in the surface waters, both large and microscopic forms being present, the latter serving as a food supply for even the largest of animals, the whale. 140. Life along Coasts (Littoral). — Along the coast line there is also abundant animal life ; but it is more varied than in the open ocean, because the coast offers so many different conditions. Some of the littoral animals swim in the surf ; others cling to the rocky coast ; and others burrow in the sand or mud. Many kinds, such as clams, oysters, lobsters, and a large number of fishes, are valuable as food ; others, such as sponges, precious corals, and pearls, are of value for other purposes. Plants, as well as animals, abound on the seacoast. This is true in the mangrove swamps of the tropical zone (Fig. 379) and the salt marshes of the temperate zones (Fig. 378) ; it is also true on the beaches. Other conditions are very favorable, especially the presence of food-bringing currents. Few parts of the earth have such an abundance and variety of animal life as the coral reefs (Fig. 380), which, are bathed by warm ocean currents. The influence of food-briuging currents is felt on those shallow Danks, known SiS JisJmig banks, where large numbers of food fish live. This is well illustrated on the fishing banks off northeastern America, such as Georges and the Grand Banks of Newfoundland, which are bathed by the Labrador current. These are resorted to for cod, haddock, and halibut by fishing vessels from France, Newfoundland, Nova Scotia, and many New England ports, especially Gloucester, Mass. From a passing ocean liner, the schooners may be seen at anchor in the open ocean (Fig. 341), the men busily fishing, either from the sides of the vessel or from small, open dories. It is a hazardous calling, and many a fishing vessel has been sunk during the fierce storms, or crushed by the huge transatlantic liners. Every year, also, men in dories are separated froju their vessels during fogs, which are frequent on the banks. They then drift about in the open ocean, often until they starve, or freeze, or founder. Summary. — Animal life along the coast is abundant and varied ; there is also much plant life. Food-bringing ciirrents especially favor life, as is illustrated on coral reefs and fishing banks, from, which valuable food fish are obtained. 141. Life on the Ocean Bottom (Abyssal). — Absence of sunlight prevents the existence of plant life in the deep sea ; but, even at depths of two or three miles, there are animals on the ocean bottom (p. 174). These animals live in darkness, in water almost at the are very uniform : summer and winter are alike ; day and night are dark ; everywhere it is cold ; and the sea floor is a monotonous expanse of ooze or clay. The nature of animal life varies with the depth because of differences in temperature ; and where the water is very cold, animals are scarce and have little vitality. The supply of there, have been exterminated. Summary. — There is ivonderfal uniformity of conditions in the deep sea, in tcMch animals, but no plants, live. The abundance and distribution of ayiimal life are influenced mainly by temperature oxygen supply, and food supply. 125. Ocean Basins. — General condition ; deep-sea plains; deeps; elevations; Atlantic, — deepest point, volcanoes, mid-Atlantic ridge; Pacific, — volcanic chains, deepest point, other deeps; Arctic; Southern Ocean. 126. Deposits on. the Ocean Bottom. — (A) Rock fragments: source; deposit ; fossils. (B) Ocean-bottom oozes : absence of rock waste ; area of ooze ; materials in ooze ; source of organisms ; globigerina ooze ; pteropod ooze ; diatom ooze. (C) Red clay : solution of shells ; insoluble parts; red color; slowness of accumulation ; proofs- 129. Composition of Sea Water. — Original condition; increase in saltness; proportion of salt; other mineral substances ; amount of salt ; importance; carbonate of lime ; presence of air ; importance. 130. Density and Pressure of Sea Water. — {a) Density : average density; effect of fresh water; of evaporation, (b) Pressure: amount; reason for no effect on animals; animals brought to the surface; density of ocean-bottom water. 131. Color and Light. — (a) Color: entrance of sunlight ; blue color; green color ; Yellow River ; Red Sea. (h) Light : darkness of ocean bottom ; blind fish ; phosphorescence on ocean bottom ; at the surface. 132. Temperature of the Oceans. — From tropical to frigid zones; inclosed seas; decrease downward; ocean bottom ; cooling of fresh and saltwater; circulation; effect on animals ; inclosed sea bottoms. 133. Wind Waves. — Cause; nature of movement; height; crest; trough; whitecaps ; rate of movement; effects on vessels; use of oil; rollers ; breakers ; undertow ; movement of rock fragments. 135. Tides. — (a) Nature of tides: time of passage; tidal range; increase on coast; movement in open ocean; currents on coast; flow; ebb. (h) Influence of coast: ordinary range; effect of V-shaped bays; of broadening bays; Mediterranean; races; examples; bore, (c) Influence of moon's phases: spring tides; neap tides; relation of tides to moon, (fl) Effects of tides : on deposit of strata ; on deposits in harbors ; on circulation of water in harbors ; on navigation. 136. Ocean Currents. — Early knowledge ; effect of temperature differences ; of steady winds ; resemblance between winds and currents ; a drift ; a stream; Equatorial Drift; effect of continents; effect of rotation ; Sargasso Sea; Gulf Stream; North Atlantic Eddy; West Wind Drift; Pacific eddies ; West Wind Drift of Southern Ocean ; Labrador Current ; compare European and American coasts. 140. Life along Coasts (Littoral). — Varied conditions ; valuable animals; plant life; unfavorable conditions; favorable conditions; fishing banks, — location, food fish, fishing, dangers. 124. What is oceanography? What expeditions have been engaged in deep-sea exploration ? How is the depth of the sea learned ? What facts are learned during a sounding? How is dredging carried on? 125. What is the condition of the ocean bottom ? What irregularities occur ? What irregularities are found in the Atlantic ? In the Pacific ? What is known of the Arctic and Southern oceans ? 126. (A) What is the nature of the deposit near the coast? (B) Why is ooze deposited far from land? Of what is it composed? (C) What is the origin of red clay ? Prove that it is forming slowly. 129. What is the origin of the mineral substances in sea water? What mineral substances are there? How much salt is there? Of what importance is the carbonate of lime ? The air? 130. What causes water to vary in density ? What is the pressure or. the ocean bottom? Why do not animals feel it? What would be the condition if the ocean-bottom water were compressed like the air ? 132. What causes differences in temperature of the ocean-surface waters? What are the temperature conditions below the surface? Why is the bottom temperature lower than that in lakes ? What is the cause of the slow circulation ? What proof is there of it? 133. What causes waves ? What is the real movement of the water ? What causes whitecaps? How high may waves be? How fast may they move? What damage may they do to ships? How may this danger be lessened ? What is the cause of rollers? What causes breakers? What is undertow ? How are rock fragments carried away ? 13.5. To what height does the tidal wave rise? Under what conditions are tidal currents formed? What is flow? Ebb? What happens as tides enter narrowing bays? Where they enter broadening bays? Give an illustration. What causes tidal races? Give illustrations. What is the bore? What reasons are there for connecting tides with the moon ? Name some important effects of tides. 136. What early knowledge of ocean currents was there ? What effect have differences in temperature on ocean movements? What effect has the wind? Describe the system of currents in the Atlantic Ocean, and show how it is related to winds. Describe and explain the Gulf Stream. What is the Sargasso Sea? What currents are found in the Pacific? Other oceans (Fig. 338) ? Describe the Labrador Current. 140. How do the conditions surrounding littoral life vary? In what situations are littoral plants found? What conditions oppose littoral life? What conditions favor it? Why are fishing banks the home of food fish ? What dangers accompany the fishing ? putting shot in a bottle until it will barely sink in fresh water, taking care to cork it; then dissolve salt in the water and again put the bottle in it. (2) Cut a cube of ice and place it in fresh water. Measure the amount above and below water. Place it in salt water and measure again. What is the result? (3) In a large pan, or tub, of water place a bottle, partly submerged. Start waves by blowing on one end. Note how they travel beyond their source. Note the movements of the bottle as the waves pass under it. Have the students describe its movements. At one end of the pan make a shelving beach of sand, with a cliff at one end. Observe and describe the action of the M^aves as they approach the shore. What differences are there in the behavior of the waves on the beach and on the cliff ? Are fragments removed ? AVhere do they go ? Make waves that advance diagonally on the shore and observe the movement of the fragments. To see this clearly, place at one point some colored objects, like bits of colored glass, and note how they move. (4) In the pan build a coast, roughly, like that of North and South America. Sprinkle sawdust on the water and blow over its surface from both sides of a line (the equator), to imitate the trade winds approaching the equator. Watch the drift of water. Do you see any resemblance to the oceancurrent systems of the Atlantic? (5) Take the temperature at the bottom of the pan near the middle line, then place ice in the water as far away from the middle as possible. Be careful not to stir the water. After the ice has melted, again take the temperature under the middle line. What is the difference? It would be possible also to imitate the conditions in the Gulf of Mexico (p. 184). (6) If the school is by the sea, or even near a lake or pond, waves and wind-formed currents should be studied. Note their force, form, and effects. (7) If by the seashore, the tides should be studied. Observe time of low and high tides for three successive days. These facts may be obtained from an almanac, or better, from the Tide Tables published by the U. S. Coast Survey at Washington, the tables for the year, for the Atlantic (15 cents) and Pa« cific (10 cents) coasts. Observe the time of spring and neap tides. How do they compare with the phases of the moon ? What is the range of the tide in each case? Are there any tidal currents near at hand ? Are the tides of any importance in your harbor? That is, do they do any harm oi good? (8) On cross-section paper, plot a curve to represent the high and low tide for a month (obtaining the facts from the Tide Tables). Let each of twelve students do a different month and then paste them all together. Above the curves indicate each quarter of the moon. Have the students study these to see how closely the phases of the moon coincide with variations in range of the tide. Let the vertical side of each square represent a foot of tidal rise, and the horizontal side, threi hours of time. (9) On an outline map of the world sketch the ocean currents from the chart in the book (Fig. 338). Reference Books. — Thompson, Depths of the Sea, 2 vols., Macmillan Co., New York, 1873, $7.50 ; The Atlantic, Macmillan & Co., London, 1877 (out of print) ; Agassiz, Three Cruises of the Blake, 2 vols., Houghton, Mifflin & Co., Boston, 1888, \|8.00; WihT>,^ Thalassa, Marcus Ward & Co., London, 1877, 12 shillings ; Moseley, Notes by a Naturalist, Murray, London, 1892, 9 shillings ; Sigsbee, Deep Sea Sounding and Dredging, U. S. Coast Survey, Washington, D.C., 1880; Tanner, Deep Sea Exploitation, p. 1, 1892 Report, U. S. Fish Commission, Washington, D.C. ; Darwin, The Tides, Houghton, Mifflin & Co., Boston, 1898, -12.00 ; Tide Tables for the Year, U. S. Coast Survey, AVashington, $0.25 ; Pillsbury, The Gulf Stream, Annual Repot "", U. S. Coast Survey for 1890, Appendix 10, Washington, D.C. SHORE LINES. 142. Importance of Shore Lines. — Some of the busiest centers of human industry are located on or near the seacoast. The great and increasing trade that uses the ocean as a highway converges toward these centers ; and to and from them, by river, canal, and railway, there is a steady movement of goods for shipment or for distribution. So important is the coast line that charts have been made of all parts of it that are reached by the vessels of commerce. Governments maintain bureaus, like the United States Coast Survey, whose duty it is to map the coast, to determine by accurate soundings the depth of water, and to detect and record all changes, such as shifting of channels, which might endanger ships. In addition, our government annually spends large sums of money for the improvement of harbors. This money is used in building breakwaters where no natural harbors exist ; in dredging out the sand and mud that waves and currents deposit ; and in building jetties and other structures to control the deposits of sediment and keep channels clear. The approach to the coast, especially in times of storm and fog, is accompanied by so many dangers — from hidden reefs, islands, and projecting headlands — that all civilized nations spend large smns in the effort to lessen these perils. To warn sailors, or to guide them into port, lighthouses are built on exposed points and light-ships anchored on dangerous shoals ; and, on the charts, the location and characteristics of these lights are shown. On approaching the coast at night, the first sign of land is the gleam of the lighthouse; and by the color, brilliancy, nature of Specially trained pilots are licensed to guide ships into port; and buoys are placed at frequent intervals to mark the channel. Some of the buoys, placed over reefs or near dangerous currents, have bells that are rung, or whistles that are blown, by the rock-, ing of the waves, to warn the sailors of danger. Even with all these precautions vessels far too frequently run ashore. To rescue the shipwrecked, life-saving stations are established at frequent intervals by state and national governments; and in them men with strong life-boats, lines, and other life-saving apparatus are ever ready for the call of distress. The coast line has become of importance to many people as a vacation resort. In summer, when the interior of the country is hot, the seacoast is cool and pleasant ; there are rocky coasts to scramble over, beaches to walk upon, surf to swim in, and boating and fishing to enjoy. Consequently, tens of thousands of people go to the seashore for a j)art or all of the summer. Summary. — The seacoast is the site of some of the busiest centers of human industry. It is so important that it is charted; harbors are built or dredged out; lighthouses, buoys, and other learnings and guides are placed along it; and life-saving stations are established. The seacoast is also an important summer resort. 143. The Seacoast is ever changing. — Waves and currents are vigorously at work, wearing away the land (Fig. 347) and moving rock fragments to places of deposit ; and rivers are ever pouring sediment into the sea. Along some coasts the waves are cutting back the cliffs (Fig. 344) at the rate of one or two feet a year (Fig. 358), as on the outer shore of Cape Cod and Martha's Vineyard. In other places, deposit is building out the coast, especially near river mouths (Fig. 345). Pisa, in the Middle Ages a seaport, is now several miles inland on the delta of the Arno, Leghorn being now the seaport for that region. A slight elevation brings cliffs, beaches, and sea-bottom plains (p. 72) above the reach of the waves ; a slight depression, allowing the sea to enter the valleys, entirely alters the outline of the coast. An elevation or depression that in the interior would pass unnoticed, causes such changes in the seacoast that it cannot escape attention. Since waves are ever at work, since deposits of sediment are always being made, and since the earth's crust is constantly rising or falling, any study of coast lines must be largely aoncerned with the effects of such changes. Summary. — The coast is being cut back by the waves in some places, and built out by deposits in others ; and many changes are made by rising or sinking of the land. 144. Elevated Sea-bottom Coasts. — The uplift of sea bottoms, forming coastal plains (p. 72), produces a low, flat, straight coast line, not generally fitted for dense settlement. Such coasts are found in southern United States, Yucatan, eastern Central America, and Argentina. The land back of the coast is often so level that it is swampy, un healthful, and unfitted for agriculture. In tropical lands, as in Central America and Africa, such plains are the seat of deadly malaria. Being made of soft, •unconsolidated deposits of clay, sand, and gravel, the soil is often so sterile as to be unsuited to cultivation. Where the soil is fertile and not too damp, however, the level plains make excellent agricultural land ; but the lack of good harbors is a handicap to development. Good harbors are rare, chiefly because the contact of the sea with a level plain makes a straight coast with few irregularities. If a slight sinking occurs, as has been the case in southern United States, the sea enters the valleys, forming bays and harbors ; but the harbors are likely to be poor, because the valleys of a coastal plain are shallow. Moreover, the waves and currents, working with loose rock fragments, quickly build sand bars, which skirt the coast, inclosing shallow lagoons, and even extending from being choked with sand. Summary. — Elevated sea-bottom plains are loc, level, straight, skirted by sand bars, and have few harbors, and these mostly shallow and poor, even ivhere sinking of the land has admitted the sea to the valleys. Such conditions do not favor dense settlement. 145. Straight Mountainous Coasts. — The uplift of sea bottoms is sometimes accompanied by mountain folding. This eitlier raises narrow strips of coastal plain, between the mountains and the sea, or else causes the mountains to rise directly out of the sea. Where the mountains rise from the ocean in long chains of folds, they produce a straight and regular coast line. Such a coast exists in western America, from Oregon tc central Chile (Fig. 346). Along this coast there are few harbors, bays, capes, and peninsulas. In many places the mountains rise directly from the sea ; elsewhere at the inner margin of a narrow coastal plain (Fig. 117). The sea bottom slopes rapidly, and, in a short distance from the coast, the water is 15,000 or 20,000 feet deep (p. 20). This cofist has been recently elevated, and, in many places, is still rising. Both in 1822 and 1835 a part of the coast of Chile was suddenly raised 2 or 3 feet ; and beaches and sea shells on the mountain slopes prove other recent uplifts. For several reasons, such coasts are not suited to dense populations and high development of industries. (1) There are so few harbors that a place, even though on the shore, may be a long distance from a shipping point. (2) Between the mountains and the sea there is, at best, only a narrow strip of fairly level laud, limiting the resources. (3) The mountains act as a barrier to inland communication, few, if any, large streams breaking across them. Peru and Chile have only recently, and at great expense, opened railway communication across the Andes barrier (Fig. 184). The scattered seaports, therefore, have little country tributary to them. Fig. 344. — Island of Heligoland, in the North Sea. The outer line represents it in the year 800, when its circumference was 120 miles ; large shaded area in 1300, circumference reduced by wave erosion to 45 miles ; inner shaded area in 1649, circumference only 8 miles. Fig. 345. — Changes in the coast of a part of Asia Minor, by deposits made chiefly by the river Maeander (from which our word "meander" is derived). Summary. — Long chains of mountains, rising from the sea, form straight coasts, as in luestern America. The scattered harbors, the narroiv area of level land, and the mountain harrier render such coasts unsuited to dense settlement or high development of industries, 146. Irregular Mountainous Coasts. — Mountain growth makes irregular coasts more commonly than straight ones. Irregular coasts result (1) when mountains rise as chains of islands near continents, as in the case of the West Indies, East Indies, Philippines, and Japanese Islands ; (2) when the ranges extend out from the mainland as peninsulas, as in the case of Italy, Greece, Alaska, and the Malay Peninsula ; and (3) when, between mountain ranges, parts of the crust sink, thus admitting the ocean and forming gulfs or seas, like the Gulf of California and the Mediterranean. The Mediterranean is a broad, deep depression (over 14,000 feet in depth) between the mountains of Europe and Africa. It is almost cut off from the ocean where the Atlas Mountains of Africa nearly meet the mountains of Spain at the Straits of Gibraltar ; it is almost connected with the ocean at the low Isthmus of Suez. Its coast line is very irregular, because there are so many short mountain chains, extending in different directions. These form the peninsulas of Tunis, Italy, Greece, and Asia Minor, besides many smaller projections ; and also chains of islands, among which Cyprus, Crete, Sicily, the Balearic Isles, and Corsica and Sardinia are the largest. The mountain chain of Italy, extending through Sicily, and along a submarine ridge to the Tunis peninsula, almost cuts the Mediterranean in two. Many other large seas, such as the Caribbean Sea, Gulf of Mexico, Japan Sea, China Sea, and Red Sea, are partly inclosed by mountain uplifts. Still smaller seas, bays, and even harbors have been made by the uplift of mountainous islands and peninsulas. Where there has been a later sinking, as in Greece, the entrance of the sea into the mountain valleys has made many small bays and deep harbors. Irregular, mountainous coasts are better fitted for habitation than straight, mountainous coasts. Communication by land is difficult, and the coast line is often steep and rocky (Fig. 348) ; but the many harbors, the great length of the irregular coast, and the quiet water of the inclosed seas and bays all encourage navigation. It is largely because of these conditions that navigation early developed in the Mediterranean (p. 377). There are many places that, even to-day, can be reached only by ship ; and the coasts, as in western Italy, are often so mountainous that a railway, although close by the sea, must pass through a series of tunnels near together. Wherever there is room for towns or villages, as on the delta of a small stream, the coast is well settled (Fig. 348) ; and, back of the coast, the settlement is especially dense along river valleys that furnish a pathway to the sea. Summary. — Uplift of mountainous islands and peninsidas, and sinking of the land between mountain folds, cause irregular coasts. Such coasts, like the Mediterranean, favor navigation because of the 7iumber of harbors, the length of the coast, and the quiet water ; but they are frequeyitly steej), rocky, and sp)arsely settled. Communication between places along them must often be by ship. 147. Coasts of Drowned Lands. — Sinking of the land drowns a portion of it and makes the coast line irregular (Fig. 349), for the valleys are then transformed to bays, harbors, or estuaries. Sinking of the land has made San Francisco harbor (Fig. 350): _o has made Massachusetts Bay, Boston harbor, and the other bays and harbors of New England ; and it has drowned the lower Hudson (Fig. 351). When the hills of a drowned land have been completely submerged, shoals and banks (p. 197) are formed in the sea. . When the hills are only partially submerged, islands are formed (Fig. 353), like the British Isles, Newfoundland, and the thousands of islands in northeastern (Fig. 354) and northwestern America. Where there has not been submergence enough to completely surround the land, peninsulas are produced, like Scandinavia, Denmark^ Nova Scotia, and mnumerable capes and promontories (Fig. 354). distance straight along the coast. Measure it along the greater irregularities. Fig. 355. — A small bay, or chasm, which the waves have cut in the coast of Cape Ann, north of Boston. Here a narrow dike of trap rock (seen in tlie middle of the picture) crosses the more resistant granite The outline of a sunken coast depends upon the nature of the valleys that existed on the land before it was submerged. Grand fiords, with wonderful scenery, are formed where the sea has entered the deep, steep-sided, mountain valleys of Norway (Figs. 352, 356) and Alaska. These fiord valleys were first cut by streams, then for the development of that race of hardy sailors, the Norsemen. The coast south of New York is strikingly different from the rocky coast farther north. This difference is due to the fact that this is a region of soft rock and plains, crossed by broad valleys with gently sloping sides. The entrance of the sea into these has formed broad, shallow bays with gently rising margins, as in Delaware, Chesapeake, and Mobile bays. Along such coasts communication by land is easy and agriculture thrives. There are several reasons why moderately low, irregular coasts, like those of the Middle States, New England, and England, are favorable to settlement and development. (1) There is an abundance of harbors, — in fact, as in Maine (Fig. 354), often far more than are needed. (2) The irregularity makes a very long coast line for fishing and navigation. (3) There are protected bays and sounds for fishing and navigation. (4) Sinking of the land opens up waterways to the interior. The Columbia, Hud- sou, and Thames are navigable to ocean ships solely because recent sinking has admitted the sea. Portland, New York, and London could not otherwise be important seaports. The formation of islands cuts off connection with the mainland and produces very important effects on the inhabitants. Thus Newfoundland is so isolated that its interests are different from those of the Canadian provinces, and it has declined to join the Canadian Confederation. The sinking of the land, which separated Great Britain from Europe at the Strait of Dover, has protected the British from inroads of invaders by land, and has forced the development of navigation and a navy (p. 389). Summary. — Sinking of the land forms bays, harbors, and estuaries in valleys, ayid makes shoals, banks, islands, aiid j^^'^^insidas of hills, thus making the coast irregular. The submergence of mountainous regions forms fiords, and a rugged coast suited to navigation, but not to dense settlement. Regions of soft rock, when drowned, have broad, shalloiv bays with gently sloping sides, adapted to agriculture. Moderately low, irregular coasts favor development because of the harbors, the favorable conditions for fishing and namgatioyi, and the opening of ivaterivays to the iyiterior. The formation of islands isolates people and greatly influences their history. 148. Wave and Tide Work. — Waves are constantly battering at the coast line, cutting cliffs where possible and moving the fragments about (p. 186). Some of the sediment is dragged offshore by the undertow and tidal currents ; some is drifted along the coast by the waves and the tidal and windformed currents. On rocky coasts this shore drift lodges between headlands, forming beaches (Fig. 364) ; on low, sandy coasts it is built into long sand bars (Fig. 372). Waves and currents are accomplishing two ends by this work : (1) cutting back the land, (2) straightening the coast. An irregular coast will not long be tolerated by waves and currents; and, Ave re it not for the fact that there are so many movements of the crust, the coast lines of the world would all be straight. When, therefore, we find an Fig. 358. — A wave-cut cliff in tiie clay on the shore of Lake Ontario. This cliff is beins^ cut backward at the rate of about two feet a year ; and, by this cutting, trees are undermined and caused to slide down the cliff face. area in front is the seaweed mat which the high tide covers. Fig. 360. — A rock cliff on the Maine coast, showing how the waves sometimes undercut, causing the hard rotK to overhang. The dark area in the foreground is the seaweed mat, covered at liigh tide. Fig. 361. — A cliff in glacial deposit on the Massa-dhusetts coast. The waves have not heen able to remove the large bowlders that were in the deposit, and they, therefore, remain as an offshore platform, showing that the land once extended out so far. irregular coast, we may be certain that the shore has not stood long enough at that level for the waves and currents to straighten it. This work of straightening coast lines is done in two ways — (1) by cutting back the headlands and (2) by closing up and filling the indentations. Summary. — Wcwes and currents are attacking the headlands and moving the fragmerits either offshore or cdong the coast, in the latter case building beaches and bars. The result of this work is to straighteyi the coast. 149. Sea Cliffs. — Where wave work is vigorous, as on headlands and on exposed island coasts, the waves are sawing into the land (Figs. 344, 347). The zone of most active wave work is almost exactly at the sea level, though the spray may dash to a height of 50 or 100 feet. The advancing breakers hurl against the cliffs tons of water, bearing sand, pebbles, and even bowlders. They act like battering rams, undercutting the cliffs along the surf line (Fig. 360), and thereby undermining the rock so that it falls and keeps the cliff face precipitous. If made of hard rock, sea cliffs are very steep (Fig. 362), though weathering, aided by the salt spray, usually prevents them from becoming vertical. If made of clay or sand, the cliffs are steeply inclined and constantly sliding down (Figs. 358, 361, 367). On exposed coasts, sea cliffs may rise several hundred feet; but generally they are much lower. Cliffs in which the rocks have uniform texture may be straight and regular; but if the strata vary, the waves discover the differences and make the shore irregular. Then chasms (Figs. 355, 357) and sea caves (Fig. 359) are cut in the cliffs along the weaker strata. These irregularities cannot be cut very far back into the land, nor to a very great breadth, because the force of the waves is soon worn out on the sides and bottom. For this reason, waves cannot carve out large bays. down until they no longer break upon it. In the open ocean entire islands have been cut away by waves (Fig. 234); leaving only shoals or reefs. As the cliffs wear back, farms and houses are undermined and caused to tumble into the sea. Such headlands, with their offshore platforms, are dangerous to navigation ; and a vessel wrecked upon the wave-beaten reefs is doomed. There is little hope that the shipwrecked sailors can escape, for there is no landing place on the cliffs, and the waves are ever breaking on the reefs near their base. It is partly for this reason, and partly because of their height, that headland cliffs are commonly selected as the sites of lighthouses (Fig. 362). Summary. — The sawing of the waves into the land cuts sea cliffs, leaving offshore platforms as the cliffs are pushed hack. Weathering 2^^'events most cliffs from being vertical, hut all are steep, even those in sand or clay. Where there are differences in the rocks, chasms, sea caves, and other small irregularities are produced. Headland cliffs and offshore platforms are dangerous to navigation. 150. Beaches, Hooks, Bars, etc. — Bowlder (Fig. 363) and pebble beaches (Fig. 364) are built of the larger rock fragments, wrested from the cliffs and driven along the coast, till they lodge in bays. Smaller fragments make sand beaches (Fig. 365) ; and the still finer clay settles in the protected bays, harbors, and estuaries, forming mud banks and flats. Some fine-grained sands form quicksands. In these are numerous particles of mica, which permit the sand grains to slip over one another when wet, so that an object sinks into the sand. In little pockets between headlands there are often small ^' pocket " beaches, sometimes called " half moon " beaches, because of their crescentic shape (Figs. 363, 366). Behind them small ponds are often shut in. On exposed coasts these beaches are of bowlders or pebbles ; in more protected places, of sand. The beaches serve as mills, in which rock fragments are ground so fine that they can be borne off by the currents and undertow. The rounded form of beach pebbles shows how they are rolled about. action of the winds. tf^Q. 366. — A cresceut beach in a small bay harbor on Santa Catalina Island, Cal. One portion of the cliffs that supply this beach is seen on the right, in the distance. There the waves have not quite consumed the land, but have left a part standing as an island. Fig. 367. —Highland Licrht cliff on the bacK shore of Cane Cod. ^Fig. 375). This cliff of loose sand is wearina: back so, fast that little vegetation is able to find root on its slippmg face. It is suppJyni^ sand for the waves and t\..t.~^nt« to drift: along the coast and build -nto sand bars and shoala Fig. 370. — A bar at North Fairhaven, N.Y., on the shore of Lake Ontario, partly shutting in a broad bay. The opening is maintained by the outflow of water from the land streams. The pebbles of which this bar is Ciade are supplied from a number of cliffs, of which Fig. 358 is one. BOflMAY Sc CO., N.Yi Fig. 373. — A portion of the south shore of Marthas Vineyard, showing how the growth of sand bars may straigliten an irregular coast by shutting in the bays and changing them to ponds. Some of the rock fragments that are moved along the coast are dropped at the entrance to bays, building bars across them (Fig. 373). If there is much drainage from the land, an opening through the bar will be maintained (Fig. 370); but if not, a bar may completely seal a bay (Fig. 373). A fresh- water pond wearing back the high cliffs (Fig. 367) at Highland Light, Cape Cod, and building bars out of the sand (Fig. 375). In the same way Sandy Hook (Fig. 368) has been built of debris worn from the cliffs of the New Jersey shore. Such bars may be straight, or they may be curved at one end, forming liooks (Fig. 374), like Sandy Hook (Fig. 368) and the curved end of Cape Cod (Fig. 375). In some places, often at bends in the shore, waves and currents from opposite directions drive pebbles or sand out into the water, building small points, or spits. Bars sometimes form an angle projecting seaward, making a Gusj), like Capes Hatteras, Fear, Lookout, and Canaveral. Other bars are often built in the lee of islands (Fig. 369). Summary. — Rock fragments, drifted along the coast, build beaches in pockets, bars across bays, long bars where large quantities of sand are supplied; cdso hooks, spits, and cusps. Tlie matericd varies from botvlders to sand, much of the Jimc clay going into the bays. Tlie beaches are mills in which rock fragments are ground up. by the waves. 151. Offshore Bars. — From New Jersey to the Rio Grande most of the coast is faced by bars at some distance from the mainland, from which they are separated by shallow lagoons (Fig. 372). One of the longest of these bars extends along the Texas coast from the mouth of the Rio Grande (Fig. 371). River water enters the lagoons, some of it seeping through the bar, the remainder escaping through gaps that the outflowing and incoming tide are able to keep open. The movement of sand along the shore constantly threatens to close these channels; and for this reason, where the channels are used as harbor entrances, as at Galveston, it is necessary to build jetties to keep the entrance deep enough for large ships. ment. The shallowness interferes with the onward movement of the waves, and where they commence to break, the sand is pushed up into a ridge or bar. The wind builds the bars still higher, raising sand dunes (Figs. 376, 377), sometimes 100 feet high. The waves gradually consume the sand bars, eating them away on the seaward side and pushing them back toward the land. Beaches and bars are often useful as places for landing boats (Figs. 348, 366) ; and for bathing they are resorted to by hundreds of people. Offshore bars are, in addition, habitable, though usually so sterile that they are inhabited only by fishermen, lighthouse keepers, and pleasure seekers. Yet some bars, like the Sea Islands off the Georgia coast (Fig. 376), where the long-fibered Sea Island cotton is raised, are excellent farm land. Here and there, too, because of the absence of other kinds of harbors on such coasts, towns and cities, like Galveston, are built on the sand bars. The destruction at Galveston in 1900 (Fig. 429) proves that cities in such situations are in danger of inundation. The sand that is drifted about in the building of sand bars often makes dangerous shoals. The shifting sands south of Cape Cod, and those near Sandy Hook, are obstacles to safe navigation ; and, on the shoals at the end of Cape Hatteras, many ships have been wrecked. Summary. — Where the waves break on shallow sea bottoms the sand is pushed up into ridges, or offshore bars, ivhich are raised still higher by the wind. Such bars, inclosing lagoons, are found along much of the coast from New Jersey to the Rio Grande. 152. Sand Dunes of the Seacoast. — On beaches, as in deserts (p. 88), there is dry sand, which the wind drifts about, often piling it up in low hills and ridges, or sand dunes., along the upper edge of the beach (Fig. 365). Sand dunes are exceedingly irregular (Fig, 377), and their form is ever changing. Between the dune hills are basins, in which, however, there is rarely any water, because the bottom is so porous. full sweep to the wind. The removal of a forest back of Coffin' Beach on Cape Ann, Mass., over a century ago, permitted the sand to move inland and destroy a farm. Dunes in France have moved inland two or three miles, destroying farms and villages to such an extent that the French government has taken up the problem of how to stop their further advance. This is being done by planting trees behind the dunes, and setting out such plants as will grow in the sterile, sandy soil. A sand-dune region is difficult to cross on account of the loose sand, and of little use to man because the soil is so sterile. But in the Netherlands the sand dunes protect the low plains from submergence. The waves are consuming this coast, having cut it back two miles in historic times. As the waves consume the beach the row of dunes behind the beach is slowly pushed inland. Summary. — Along many coasts irregular sand hills, or dunes, are built up by the wind, and their advance inland has in some cases caused the destruction of much property. In the Netherlands the sand dunes act as a barrier, protecting the low plains from the ivaves. 153. Salt Marshes. — Sediment deposited in estuaries, in lagoons behind sand bars (Fig. 372), and in other protected arms of the sea, is slowly filling them. Salt-water plants that flourish in these places, such as the eel grass and salt-marsh grasses, aid in the filling. Their aid consists partly in adding their own remains, partly in checking the currents, thus causing them to drop some of the sediment they carry. In time, the deposit of sediment and plant remains reaches to the level of high tide, forming a salt-marsh plain through which extend channels that the tide occupies (Figs. 372, 378). When, by wash from the land, the plain is built higher than the highest spring tides reach, dry-land plants take the place of the salt-marsh plants. By this process, nature is engaged in reclaiming much land from the sea. Fig. 377. — Sand dunes on the offshore bar of the New Jersey coast. The dune hill in the foreground is protected from removal by a cluster of bushes ibavberries^ which have taken root there. Fig. "378. — A salt marsh plain in an estnary at Cape Ann, Mass. View taken at mid-tide to show the channel-ways filled with water. During high tide the entire plain is submerged beneath tbe sak water. In the United States little has been done to reclaim salt marsh, because we have had enough land without it. But the time cannot be far distant when the extensive salt marshes near New York and Boston will repay diking. Boston is partly built on salt marsh that has been changed to dry land by filling with earth removed from neighboring hills. Summary. — //i protected hays and lagoons, sediment and the remains of salt-water plants build up salt-marsh plains. In places these have been reclaimed by dikes or by filling. 154. Mangrove Swamps.' — ^ Mangrove trees grow in protected spots on the coasts of warm countries, such as the Philippines, Bermuda Islands, and southern Florida. The mangrove tree (Fig. 379) is firmly anchored by roots that descend from the branches, forming an almost impenetrable jungle, or mangrove swamp. almost impenetrable jungle of the mangrove swamp. 155. Coral Reefs. — On some warm coasts animal life is so abundant that tlie shore is made entirely of animal remains. Of these animals, corals are the most important. Reefbuilding corals thrive only in depths less than 150 feet, where there is little sediment, little fresh water from the land, currents bringing abundant food, and a temperature never below 70°. Coral is made by lowly animals, of which there are many species, varying in size from almost microscopic to individuals several inches in diameter. Some species live singly, but most unite in colonies, together forming a limy framework (as animals form their bones), which we call coral. Some corals are massive, Dowlder-like domes, others, delicately branching, treelike forms. The individuals, or 2^oly2)s, which form the coral, dwell in little cavities that dot its surface. The coral mass is alive on homes on foundations laid by former generations. The polyps can either withdraw into the cavities or extend their branching arms into the water in search of food. To one looking down upon a coral reef, through a box with a glass bottom, the sea floor seems like a garden, with flowers of all colors and many forms ; and among the corals are myriads of other animals, some fixed in place, some moving freely about. The abundance and variety of life in such a place is marvelous. Coral growth is most rapid on the outer side of a reef, where food is most abundant. This causes reefs to grow seaward, and their outward growth is increased by the action of the waves, which break off coral fragments and drag them out to sea. A reef may start close to shore, as a fringing reef and advance so far that it becomes a harrier reef. Another way in which a fringing reef may be changed to a barrier reef is by a slow sinking of the land. If the coral grows upward as' fast as the land sinks, it will form '^ reef farther and farther from the sinking land. There are coral reefs on many coasts, the longest in the world being the Great Barrier Reef (Fig. 380), which for over 1000 miles skirts the northeastern coast of Australia at a distance of 20 to 50 miles. Behind it i^ a navigable lagoon of quiet, protected water, in which, however, a good pilot is necessary, because of the many coral shoals. Uplift of the coast adds coral reefs to the land, in the form of terraces, like those in Cuba and other islands. Even in the interior of continents, fossil reefs are found in some of the limestone strata that were deposited in ancient oceans. Waves and winds often heap the coral fragments above sea level, forming land, as in the Bermuda Islands. The Bermudas, whose base beneath the sea is a volcanic cone, are surroimded by a fringe of coral reefs. Fragments, broken from the reefs by the waves, are ground on the beaches to coral and shell sand, then drifted inland by the winds, forminc sand dunes. These are quickly cemented into a soft rock by the deposit of carbonate of lime around the grains. The Bahamas, and many other coral islands, are made in the same manner. The soil of such dunes is far better than the soil of ordinary sand dunes. Summary. — In tvarm, clear water, where there is an abundance of food for fixed animals, corals thrive, building limy skeletons, out of ivhich reefs are made. Fringing reefs are made along the coast, and these may change to barrier reefs either by outward growth or by sinking of the land. T7ie ivind often forms dunes of the coral sand drifted from the beaches, thus making land m the sea. 156. Atolls. — Ring-shaped islands in the open ocean, made of coral fragments, are called atolls (Fig. 382). A channel into the interior lagoon is kept open by the incoming and outgoing tides. Atolls are especially common in the South Pacific, and are in some cases several miles in diameter, though rarely rising more than 12 to 15 feet above sea level. They are so low that during hurricanes they are sometimes inundated by the sea. Like the Bermudas, the part above water is made of coral and shell fragments that the waves have thrown on the beach and the wind drifted into low hills. atolls are inhabited by man. Atolls are built on the peaks of extinct volcanoes that -rise from the sea bottom. Sometimes they seem to have been built on !i ibmerged peaks, the ring shape being due to the faster growth on the outside of the reef, while within the lagoon much of the lime of the coral is removed by solution. In other cases the atolls appear to be due to a slow subsidence of volcanic cones (Fig. 385). According to this explanation there was first a volcanic island surrounded by a fringing reef (Fig. 381); by slow sinking this changed to a barrier reef ; finally, when the cone had entirely disappeared, there was a ring-shaped atoll where the cone formerly rose. The sinking of the cone could have been EO faster than the upward c:rowth of the reef. Summary. — Low, ring-shaped coral islands in the open ocean are ccdled atolls. They are built on volcanic cones. In some cases at least, they are caused by a subsideyice of the cone at about the same rate as the upward growth of a fringing reef 157. Lake Shores. — Most that has been said about sea> coasts applies quite fully to lakes ; and illustrations of most shore-line phenomena are found along lake shores. There are headlands, Avave-cut cliffs, beaches, bars, sand dunes, islands, promontories, and harbors. There are also elevated and drowned coasts. In fact, from tlie form alone it is quite impossible to distinguish lake from ocean shores. Figures 358 and 370 are from lake shores. It is true that tides are absent in all but the largest lakes, and even there are almost unnoticeable ; and, because the waves are less violent, the cliffs are usually smaller, resembling those of bays rather than the open ocean ; but in great lakes there are some high cliffs. The effects of life are, however, quite unlike in the two cases. Although swamps are formed in the lagoons and bays of lakes, the plants are very different from those of the salt marsh ; and the absence of tide makes the difference between lake and seashore swamps even more marked. In lakes there are no corals, and, consequently, no coral reefs. Summary. — Lah:e and sea-coasts are so alike that, from the form alone, they could not be distinguished. The chief differences are the smaller cliffs, the absence of tides, and the effects of life. 158. Abandoned Shore Lines. — In many places where lakes have disappeared, clitfs and beaches are now found on the land. For example, very perfect beaches, bars, spits, and cliffs are found near Great Salt Lake, marking the shore line of ancient Lake Bonneville (Fig. 301). Similar shore lines mark the level reached by the glacial lakes in the valleys of the Ked River of the North (Fig. 130) and the Great Lakes (p. 150). Such beaches are seen at or near Duluth, Chicago, Cleveland, Rochester, Syracuse, and many other points. They are so much like ocean shore line? Fig. 383. — A wave-cut cliff on the French coast. In cutting back the land, the waves have left a " stack " island. Another will be formed when the roof of the wave-cut cave falls. Fig. 388. — The drowned coast of a part of southern New England. Notice the small hays partly or completely shut in by bar. (A part of the United fctates Geological Survey ^^ew London, ^onn., Sheet.) sinking of the land, admitting the sea into these valleys. Elevated sea beaches are found from southern iSTew England to Baffin Land. Near Boston these beaches are from 40 to 60 feet above sea level ; in Labrador several hundred feet. There are also elevated beaches in Norway, Scotland, and other parts of northwestern Europe. Here the country back of the elevated shore lines is irregular, rocky, and not well suited to farming ; but between the elevated beaches and the present shore is a narrow plain which is good farm land and well settled. It is an elevated sea bottom, from which the waves have partly removed the islands and promontories, and over which sediment has been strewn (Fig. 386). Proof of former wave work at these higher levels is furnished by elevated beaches, marine fossils, islands partly cut away, and cliffs (Fig. 384) with sea caves and chasms. Summary. — Shore lines, closely resembling marine shore lines, Tuiark the sites of extinct lakes; and elevated sea beaches are found in northeastern America and northwestern Europe. 159. Life History of a Coast Line. — Elevations and depressions of tlie land are so frequent that, before the waves have carried their work very far, some change in level brings new regions within their reach. If a coast were allowed to pass through its life history uninterrupted, the changes would depend on the nature of the rock, the form of the coast, and the force and direction of waves and currents. We will start with a rocky, irregular, exposed coast, like that of New England, — a typical young coast line (Fig. 386). Slowly the headlands are cut back (Figs. 362, 383), some of the materials being moved offshore, some driven along the coast. Of the materials driven alongshore, bars are made, tying islands to the mainland (Fig. 369) and closing the bays (Figs. 370, 373). Sediment slowly fills the bays, transforming them to salt marshes (Fig. 378), then to dry-land plains. This straightened coast is a mature coast line. As the waves continue to cut back the headlands, the beaches and bars are also pushed back, and thus the entire coast line retreats. If the rock is weak, less time is required for this life history •, and if at the beginning the coast is not very irregular, less time is required to straighten it. On coasts of loose sand and clay, with gently sloping bottom, cliffs are first cut, then offshore bars are thrown up (Figs. 371, 372, 387). As in the case of other straightened coasts, the waves then gradually push the barrier beaches back toward the land. Coral coasts have a different life history, for they depend on the growth of animals. Summary. — Young coasts are irregular ; as they advance toward maturity lieadlayids are cut hack, hay mouths are closed, and irregularities are filled ; then both headlands and beaches are slowly moved backward as the land is consumed, TJiis life history requires a longer time in hard than in soft rock. On gently sloping coasts of soft rock, one of the earliest stages is the building of offshore bars, 160. Islands and Promontories. — Perhaps the greatest number of islands and promontories are due to sinking of the land (Figs. 349, 352-354, 388, 389), as illustrated by those of northeastern and northwestern America, northwestern Europe, southern South America, and the Grecian coast. Other islands and promontories are built by mountain growth (pp. 98, 207). Alaska, Lower California, the West Indies, the large peninsulas and islands of the Mediterranean, Madagascar, New Zealand, the East Indies, the Malay Peninsula, the Philippines, the Japanese islands, Korea, and many chains of oceanic islands are of this origin. Many islands in the open ocean are volcanoes (pp. 124, 175) ; for example, the Azores, Canaries, Madeiras, and Hawaiian Islands. Atolls and many coral reefs are islands built by animal life, aided by waves and wind (p. 218). These are illustrated by the Bahamas, Bermudas, and the islands off southern Florida, including Key West. Some coral reefs are attached to the land, forming promontories. The formation of barrier beaches (p. 214) is another cause for islands and promontories (Figs. 368, 375), as illustrated along the coast of the United States. Deltas are often promontories; and along their shores are many small islands and Dromontories that the waves havp thrown up (Fis:. 105V Another cause of islands and promontories is the more rapid work of the waves in removing weak strata (p. 211). Small islands thus cut from the mainland are called stacks (Figs. 366, 383). inclosing a lagoon between them. Promontories and islands form irregularities of the coast line, and are usually the boundaries of bays, or other indentations. Therefore, the causes for islands and promontories also explain most of these indentations. Summary. — The majority of islands and promontories are caused by sinking of the land. Other causes are mountain growth, volcanic action, coral reef building, the formation of barrier beaches, the growth of deltas, and the irregular cutting by ivaves. Bars deposited behind islands often change them to promontories. Tliese causes tlso account for most of the bays and other indentations. 161. Harbors. — No feature of the seacoast is more important than the harbors, or small indentations of the coast, deep enough for vessels to enter, and protected enough for them to remain safe from wind and wave. By far the greater number of harbors are caused by sinking of the land, admitting the water into the valleys (Figs. 350, 388, 389) ; but there are many other causes for harbors. Some, like that of New Orleans, are on large rivers wher'' there has been little or no sinking ; others, like that of Naple.«_ occupy bays formed by mountain uplift ; and still others, like that of Callao, are merely part of a straight coast where an island serves to cut off the winds and waves. What is the cause for Galveston harbor (p. 214) ? There are others of similar origin. The lagoon of an atoll (Fig. 382), and a volcanic crater breached by the sea (Fig. 234), may also form harbors. Among other causes is the work of man ; for he has made many harbors, either by dredging shallow tidal rivers, as at Glasgow, or by building breakwaters on harborless coasts. For a harbor to be useful at the present day, and to become the site of a great city, it must be deep enough to admit large vessels. It was partly because of the shallowness of its harbor that Salem was outstripped by its neighbor Boston ; but, of late, even Boston harbor has needed deepening and improvement to admit large modern ships. To become the site of a great city, a harbor should also have a large area of productive country tributary to it. Baltimore, Pliiladelphia, New York, and Boston harbors are open to shipment not only from the country round about, but also from the great interior ; and New York owes its superiority over tlie others largely to the fact that it has connection witli the interior by water as well as by rail. On the other hand, Castine, Me., has a better harbor than even New York ; but it is not connected with an extensive productive country, and consequently has not developed. Harbors, like many other coast forms, are temporary affairs. If the coast remains at one level, and man does not interfere, bars will grow across harbor mouths and they will be slowly filled with, sediment. Both of these processes are in operation, and it is necessary to expend large sums of money to remove the deposits. This is especially true on sandy coasts, where the waves and currents find much loose material to drift about. For this reason the entrance to New York harbor is through a long, tortuous channel dredged out amid shoals of sand drifted from the sandy shores of Long Island and New Jersey. Summary. — A harbor is an indentation of the coast, deep enough for vessels to enter and yet be protected from winds and waves. There are numerous causes for harbors, of which sinking of the land is most important ; man also makes harbors by dredging or by building breakwaters. To be the site of a great city, a harbor must be deep enough for large vessels and have an extensive area of productive country tributary to it. Waves and currents are tending to seal up and fill harbors. Topical Outline. — 142. Importance of Shore Lines. — Centers of industry; shipping; charts; Coast Survey; harbor improvements; dan gers of approach; lighthouses; light-ships; fog-horns; pilots; buoys; life-saving stations; summer resorts. 146. Irregular Mountainous Coasts. — Cause of islands ; of peninsulas ; sinking of crust between ranges ; Mediterranean, — cause, entrance, irregular coast ; other large seas ; small irregularities; sinking of coast; settlement; communication by land; navigation; western Italy. 147. Coasts of Drowned Lands. — (a) Resulting irregularity : bays and harbors; instances; drowned rivers; shoals and banks; islands; peninsulas, (h) Fiord coasts: origin of fiords; instances; settlement, (c) Regions of soft rock: effect on coast form; settlement, {d) Importance of irregular coasts : harbors; length of coast line; fishing and navigation; interior waterways; instances. (e) Islands: isolation; Newfoundland ; Great Britain. 149. Sea Cliffs. — Zone of wave work; work of breakers; steepness of cliffs, — hard rock, soft rock, height; chasms; sea caves; limit to wave work ; offshore platform ; cutting back of land ; dangers to navigation, 150. Beaches, Hooks, Bars, etc. — Disposition of fragments; quicksands; pocket beaches; grinding of pebbles; bars across bays; bars supplied from sea cliffs ; hooks ; spits ; cusps. 151. Offshore Bars. — Instances; lagoons; gaps in bars; closing of gaps; cause of offshore bars; effect of wind; destruction of bars; occupants of bars ; cities on bars ; shoals. 155. Coral Reefs. — Favoring conditions; differences among corals; polyps; abundant life in a coral reef ; growth of reef; fringing ^-eef; barrier reef ; two causes for barrier reefs ; Great Bai'rier Reef ; elevated reefs ; making of land ; Bermudas. 159. Life History of a Coast Line. — Controlling conditions; young coast; changes in young coast; mature coast; consuming of land; effect of weak rock ; offshore bars. 160. Islands and Promontories. — Sinking of coast; mountain growth : volcanoes ; coral reefs ; barrier beaches ; deltas ; instances of each ; wave work; stacks; tied islands; causes of indentations. 161. Harbors. — (a) Definition, (b) Causes : sinking of land; rivers; mountain uplift ; islands ; lagoons behind barrier beaches ; atoll lagoons ; crater harbors; work of man. (c) Sites of great cities: depth; tributary country ; illustrations, (rf) Sealing up of harbors : bars ; filling Questions. — 142. For what is the coast most important? What does the government do to fit it better for commerce? To warn sailoi'S of danger ? To protect them? Why is the coast a summer resort? 145. What are the results of the rising of long chains of mountains? What is the condition on the coast of western South America? Why aro such conditions unfavorable to dense population ? 147. What results are produced by entrance of the sea into valleys ? Give illustrations. What are .the results of complete or partial submeroence of hills ? How do the nature of the rock and the vallev form iufluence the coast outline? What effect has this on settlement? Why are moderately low, irregular coasts favorable to settlement? What effect has sinking of the land on island people ? Give illustrations. 149. How are sea cliffs formed ? How do cliffs in hard and soft rocks differ? What effect has variation in strata? What are the results of cutting cliffs back? What effect has this on navigation? 155. Under what conditions do corals thrive? How is the coral made? How do the polyps live? How do the reefs grow? In what two ways may fringing reefs be made? Describe the Great Barrier Reef. What is the origin of the Bermudas and Bahamas? 159. What causes are there for variation in the life history of a coast line ? State the life history of a hard rock, irregular coast. What differences are there where the rock is weak ? 160. State the different causes for islands and promontories. Give instances wherever possible. How may an island be changed to a promontory? What are the causes of indentations? 161. AVhat is the cause for most harbors? State other causes for harbors. What two factors are of importance in determining the growth of cities about harbors ? Give two instances. Why must money be spent to imorove harbors? Suggestions. — (1) Take some angular fragments of a soft rock, or brick, and shake them for a few moments in a fruit jar containing water. What causes the water to become muddy? Find out how marbles are rounded. (2) In a shallow pan, mold an irregular land of clay. Carefully pour in water until the land is partly drowned. Study the land forms produced. Blow on the water surface, causing the waves to reach the coast diagonally. Are any bars formed ? Any other coastline features? Study and describe them. Now draw off some of the water to leave the shore line elevated. Describe the new coast line. How does it diifer from the former ? Cause waves to attack it, and describe the result. By using care, and by making the land of materials varying in hardness, much concerning shore-line phenomena may be simply and easily illustrated. (3) If the school is near the seashore or the shore of a lake, at least one excursion should be made to study shore phenomena. Are there beaches? Where does the material come from ? Are there cljffs ? What is happening there? Have any portions been recently removed by the waves? Do the bowlders or pebbles show signs of rounding? What is the cause? Where does the finer ground-up material go? Are there any mud flats ? What is the source of the material? Ask some fisherman what material covers the bottom offshore. Are there salt marshes? What are their characteristics? Are tidal currents performing any work ? (4) If the school is on a sea or lake port, the harbor should be studied ; its form ; depth (making use of a Coast Survey map) ; cause ; nature of bottom ; improvements made ; others needed ; lighthouses; other guides and aids to entrance ; source of principal materials received for shipment; of principal imports; places to which these are distributed; reasons for importance of port. If not on a harbor, the nearest large port should be studied in a similar way by means of the Coast Survey or Lake Survey charts (see Appendix J). Reference Books. — Shaler, Sea and Land, Scribuer's Sons, New York, 1891, ^2.50; Tarr, Chapter X, Pht/sical Geography of New York State, Macmillan Co., New York, 1902, \|3.50; Siialer, Beaches and Tidal Marshes of the Atlantic Coast, National Geographic Monographs, American Book Co., New York, 1895, $2.50 ; Gilbert, Features of Lake Shores, 5th Annual U. S. Geological Survey, p. 75 ; Shaler, Salt Marshes, 6th Annual U. S. Geological Survey, p. 359; Shaler, Harbors, 13tii Annual U. S. Geological Survey, p. 99 ; Darwix, Structure and Distribution of Coral Reefs, Appleton & Co., New York, 1889, $2.00; Dana, Corals and Coral Islands, Dodd, Mead & Co., New York, 1895, $5.00. THE ATMOSPHERE. 162. Composition of the Air. — (A) Oxygen^ Nitrogen^ and Carbon Dioxide. — Until recently air was believed to be a mixture of two gases, oxygen (about 21 per cent) and nitrogen (about 79 per cent).^ Oxyen is of vital importance to animals, for all breathe it ; but nitrogen, though used by some plants, is of far less importance. It, however, increases the bulk of the air and dilutes the oxygen. Man probably could not live in an atmosphere of pure oxygen, for it would cause too rapid changes in the tissues of the body. About 0.04 per cent of the air is carbon dioxide (often called carbonic acid gas), which, in spite of its small quantity, is very important. It is composed of one part of carbon and two of oxygen, and plants have the power of separating them, building the carbon into their tissues. In the bodies of animals, on the other hand, oxygen unites with carbon by a process of slow combustion, and with each breath carbon dioxide is returned to the air. Fire is a more rapid form of combustion, oxygen combining with the carbon of the wood, coal, oil, etc., and forming carbon dioxide. All forms of combustion, whether rapid or slow, produce heat. In such rapid combustion as fire, sufficient heat is produced to do much work, — for example, the formation of steam, whose energy may be used to run locomotives or 1 In 1895 a new element, argon, was discovered in the atmosphere, and siiice then several other inert elements have been found in it. They resemble nitrogen so closely that, although they are taken with every breath, they were never before detected. duced to form the energy which animals need for life. Summary. — The atmosphere is a mixture of gases. Argon and nitrogen are quite inert ; carbon dioxide, which exists in very small quantities, is of vital importance to plants; oxygen is breathed by \dl animals, in which it produces slow combustion, giving the necesaary heat for life. It also causes rapid combustion in fire. (B) Water Vapor. — Vapor rises from all damp surfaces and water bodies ; that is, liquid water is evaporating or changing to an invisible gas. This is the reason why wet clothes become dry when hung on a line, and sidewalks, after a rain. The amount of vapor water varies from place to place, some regions having very dry air, others damp or humid air. Even in the same place the amount of vapor differs from time to time, some days being humid, others dry. When the air is dry, evaporation is rapid and the sky clear ; but when there is much vapor, there may be clouds and rain. The condensation of this water vapor gives rise to dew, frost, fog, clouds, rain, snow, and hail. and damp surfaces, is also mixed tcith the air, in varying amounts. (C) Dust Particles. — Solid particles that float in the air are called dust. Some of these are whirled up from the ground by winds ; some are b:ts of carbon from smoke, or pollen of plants, or microbes. Dust particles accumulate around cities, causing a dull, hazy atmosphere; but during long periods of drought, or wlien forest fires are burning, the air even in the country becomes hazy with dust. Rain washes dust from the air, so that it is usually clearer after a rain storm. Over the ocean, and on high mountains, the air is quite free from dust particles. Dust is important in furnishing solid particles around which vapor condenses to form fog and rain. The microbes are drifted about by the winds, thus helping to spread disease. the atmosphere from sea level to higher regions. 163. Effect of Gravity. — Although light and invisible, air has perceptible weight. One particle, drawn down by p-ravity, presses on those below it, as stones in a pile press on those beneath. Since the air extends to a height of two hundred miles or more, this great column has a weight that can be measured. At sea level, its average weight is 15 pounds to every human body, it is evident that each of us bears a great weight of air; but as the pressure is equal, both inside and out, we do not notice it (p. 181). If this pressure were suddenly removed from the outside, the expansion of the air within our bodies would burst many of the tissues. Pressure pushes the molecules of gases closer together; and, therefore, the air is denser near the earth than higher up (Fig. 391). As a result of this, fully two thirds of the atmosphere is within six miles of sea level; and the air is about half as dense at the top of a high mountain, like Mt. St. Elias, as at its base. . The air on mountain tops is so thin, or rarefied, that it is difficult to breathe oxygen enough for the needs of the body. Some men and animals have become accustomed to this rarefied air and are able to live in high altitudes; but a traveler from lower levels finds his breathing greatJ}^ quickened by the effort to get enough oxygen, and not uncommonly he becomes quite exhausted. Air is so extremely elastic that even slight differences in temperature change its density or weight. For example, the air filling a room 10x20x20 feet weighs 301 pounds at 60°; but Summary. — Air has iveiglit, at sea level about fifteen pounds to the square inch. It is compressed, or more dense, at the bottom ; and lighter, or more rarefied, higher up. It is very elastic, varying in density with temperature, and being easily set in motion. 164. Light.^ — A form of energy, commonly called light and heat, is emitted by bodies having a high temperature ; for example, burning coal, red-hot iron, and the white-hot sun. This energy travels at great speed, crossing the 93,000,000 miles which separates earth and sun in about 8 minutes. Tlie sunlight which comes to us is made of a series of waves, differing in length and color, whose union forms white light. If a beam of sunlight is allowed to pass through a threecornered glass prism these waves are turned, each at a slightly different angle. The beam enters as white light, but comes out with the color Avaves separated, among which violet, indigo, blue, green, yellow, orange, and red may be recognized. This bending of light rays is called refraction; the colors are called the colors of the spectrum., or of the rainbow. Some of the rays that reach a body pass away from it, or are reflected. This is especially true of smooth surfaces, like water, or the glass of a mirror ; but it is true even of irregular surfaces, like the ground. It is reflected sunlight that makes the moon and planets appear light ; and the earth would have the same appearance if seen from them. passes through the atmosphere. Mirage is caused by reflection ^ A thorough study of the nature and behavior of light belongs to physics i but the student of physical geography should understand the main reasons ior the color phenomena of the atmosphere. «vhen layers of air have different temperatures and, consequently, different densities. It is especially perfect in deserts and on the sea, commonly showing objects inverted — a vessel with the masts downward, for instance. In deserts mirage causes an appearance of water which is often very deceptive. Rainbows are caused by refraction of light in its passage through raindrops, and reflection of the spectrum colors thus produced. The halos around sun and moon are due to similar changes in the light rays, in their passage through the ice crystals of thin, fleecy clouds high in the air. The colors of leaves, flowers, and other objects are due to reflection. When light reaches some objects, for example white paper, all the waves are reflected and the paper appears white. Other objects, like black cloth, reflect very little light, the rays being absorbed. Still other objects absorb some of the waves and reflect others, thus giving color. A red flower, for instance, reflects an excess of red waves ; and green leaves, green waves. Diffraction, or selective scattering, is an important cause for color effect in the sky. Dust in the air interferes with the passage of light waves, as small pebbles in shallow water interfere with water waves. By this interference, some of the waves that make the white light are turned aside, or scattered. The weaves having the shortest length, or those on the violet end of the spectrum, are most easily turned aside ; that is, they are selected for scattering. The blue color of the sky is due to the selective scattering of the short blue waves. When there is much dust in the air, the longer red and yellow rays are scattered, giving red and yellow colors to the sky. These colors are especially common at sunrise and sunset, when the rays pass for a long distance through the lower dust-filled layers of the air (Fig. 392). The varied cloud colors of sunrise and sunset are the result of reflection of colors caused by refraction and diffraction. Summary. — Wliite light is made by the uyiion of a number of ivaves of different length, ivhich, tvhen separated by refraction, give the colors of the spectrum. These colors may be reflected, as in colored objects, rainbows, halos, and clouds at sunset. The scattering. color to the sky and the reds and yellows of sunrise and sunset. 165. Heat. — (A) Radiant Energy. — On approaching a hot stove one feels its warmth, even at a distance of several feet. Waves of heat from the stove have passed that distance through the air. If the stove is very hot, the cover may be red ; then the waves from it produce not only heat, but the sensation of light on the eye. This form of energy, which we call heat and light, is known as radiant energy^ and the process of emitting it is called radiation. The greatest wellknown center of radiant energy is the sun ; but doubtless some of the stars are still larger and hotter, though so far away that they do not influence us. Radiation causes a loss of heat, and by it bodies grow cooler ; thus, in a few hours, a stove with the fire out will radiate all its heat and become cold. The sun is also losing heat, radiating it outward in all directions ; but millions of years will be required for so large and hot a body as the sun to grow cold. A very small proportion of the heat radiated from the sun is intercepted by the earth (Fig. 15), where it causes many important effects. Summary. — Hadiant energy, heat ayid light, which is emitted from hot bodies, is being radiated in all directions from the sun, which is, therefore, slowly growing cooler. (B) Passage of Radiant Energy. — Certain substances, like glass and the gases of the air, allow light to pass so freely that they are said to be transparent. They also allow heat to pass freely, or are diathermanoiis. For this reason, notwithstanding the thickness of the atmosphere, the sun's rays at midday reach the earth's surface with little change. Dust particles interfere with the passage of light rays, as we have seen ; and, in much the same way, they interfere with the passage of heat. This is clearly proved by the difference in brightness and warmth of the sun at midday and late in the afternoon; for we may often actually look at the setting sun. At that time many of the rays are intercepted in their passage through the great thickness of dust-laden air nea: ^he surface (Fig. 392). Summary. — Air and other substances transparent to light allow heat to freely pass, or are diatherinanous. Hie interference of dust greatly lessens the sun'' s power ivhen it low is in the heavens. (C) Radiation from the Earth. — Bodies that are warmer than their surroundings emit waves of radiant energy. The earth itself is radiating into space the heat that comes to it from the sun; if this were not so, it would grow warmer* and warmer. During the day more heat comes than can be radiated; but at night, when the sun's rays are cut off, radiation cools the ground. In summer, when the days are longer than the nights, the ground grows steadily warmer; but in winter, when the days are short and the sun low in the heavens, radiation is so far in excess of the supply of heat that the ground becomes cold. Some bodies are much better radiators than others. Rocks and earth radiate heat better than water, and hence cool more quickly. This is one reason why, in winter, the land becomes colder than the water. On cold nights those objects that radiate their heat most quickly have most frost. Perhaps you can observe this difference early some frosty morning. Summary. — The earth is always radiating heat, and this is ichy it becomes cool or cold at night and in winte7\ Some objects, like water, are poorer radiators than others, like the ground. (D) Reflection and Absorption. — Bodies that reflect light also reflect heat. Water, for example, reflects a large percentage of the rays that reach its surface, and this is why one becomes sun-burned so easily on water. Quarries and city streets are warmer than the open country, partly because the sun's rays are reflected from their walls. Some bodies reflect little, the sun's rays being used mainly in warming them. Such bodies are said to absorb heat. This can be readily proved in winter by placing two pieces of cloth, one black, the other white, on a bank of snow in the sunlight. The black cloth soon sinks into the snow because the sun warms it, while the white cloth remains at the surface. warm more rapidly. (E) Conduction. — With a fire inside of it a stove becomes warm ; and an iron placed on the stove, is also heated. In this case heat from the fire is transmitted, or conducted, through the stove. In the same way, some of the sun's heat is conducted below the surface of the water or ground, and some of it into the air which rests on these; but water, air, and ground are not so good conductors as iron. The ground is so poor a conductor that, at a depth of from ten to twenty feet, there is practically no difference in temperature from summer to winter. cdl poor conductors, (F) Convection. — The lower layers of water in a kettle on a stove are warmed by conduction. Warm water is lighter than cooler water, and, since gravity tends to draw the heavy water to the bottom, these warm lower layers cannot stay there. They are, therefore, crowded up by the settling of the cooler layers from above. This is convection, and, if the water continues to warm, boiling finally takes place. Similar convection occurs in air warmed by a lamp. As fast as it is warmed near the lamp it grows lighter and is pushed up by heavier surrounding air. The movement of heavier air to crowd up warm air is what causes the draft 'n a fire ; and the crowding upward of the warm air is what \;auses it to go up the' chimney. Heat from the sun is the cause for very extensive convection of the air in all parts of the earth. Warmed in one place, usually by conduction of heat from the ground or water, the warm light air is pushed away by heavier air drawn down by gravity. This is the cause of winds (p. 255). Summary. — Heat makes both water and air lighter; and gravity ^ by drawing doion heavier air, causes a rising, or convection, of the warmer lower layers. Winds are thus caused. 166. Warming of Land, Water, and Air. — (A) The Lands. — The lands are warmed by absorption during the day, and some of the heat is conducted into tlie ground, warming the upper few feet into which the roots of plants reach. The ground nowhere becomes excessively warm, because much of the heat is lost by reflection, by radiation, and by conduction into the air. Everywhere the ground warms during a hot, sunny day, and cools by radiation at night. In the tropical zone the ground does not become very cool at night, because radiation is unable to remove all the heat that comes during the long, hot days. A similar condition --^ists during summer in the temperate zones ; but, in winter, radiation during the long nights so chills the ground that it freezes. In the frigid zones, radiation during the long winter causes the ground to freeze to depths of hundreds of feet, and the short, cool summer supplies only heat enough to melt the upper two or three feet. There are other differences in the warming of the lands. For example, dark-colored surfaces warm more quickly than light, and bare earth more quickly than that covered by vegetation. There are also differences according to exposure ; for instance, between shady north slopes and sunny south slopes, and between hilltops and valleys, whose sides reflect heat into the valley and also interfere with winds and with radiatiou. Summary. — TJie lands are warmed by ahsoi'ption and cooled b^ reflection, conduction, and radiation. The effect of sun^s heat variea in different zones; also according to the color of the surface, the cover of vegetation, and the exposure. (B) The Waters. — It is a well-known fact that water warms less quickly than land. There are several reasons for this. (1) Water reflects heat more readily than land, and, consequently, there is less heat to warm it. (2) When one part is warmed more than another, it is set in motion, so that there is a tendency for the heat to be distributed. (3) Water is so transparent that, unlike ground, some of the rays pass into it, warming layers below the surface. Sunlight penetrates, though dimly, to depths of several hundred feet. (4) Twice as much heat is required to raise the temperature of a pound of water one degree as of an equal quantity of rock. Some of the heat is expended in evaporating the water, and this is called " latent heat," or heat of vaporization. It is for these reasons that even a small body of water warms more slowly during the day, and during summer, than the neighboring land (p. 165). At night-time and in winter, on the other hand, because it is a very poor radiator, water cools more slowly than land. Therefore, from day to night, and from summer to winter, there is slight range of temperature in large water bodies, and the climate over them is far less extreme than over land. A climate with such slight changes of temperature is called equable. Summary. — • Water warms more sloivly than land because it reflects more heat, is movable, is transparent, and some of its heat is expended in evaporation. It cools more sloivly because it is a poorer radiator. TJierefore near large water bodies the climate is equable. (C) The Air. — The air is not perfectly diathermanous. Therefore, some of the sun's rays, and some of the heat rays radiated from the earth, are intercepted in their passage through the atniosphere- Dust is especially effective in intercepting heat waves (p. 234). A still more important cause for the warming of air is conduction from the ground to the lower layers, which, being lighter, are then forced to rise by convection. In the same way a stove warms the air in a room, by radiation, conduction, and convection. At night and in winter the air cools by radiation ; and contact with the ground is another important cause for cooling. Vapor and dust interfere with radiation, and for this reason more heat is retained in the lower atmosphere on hazy and muggy days than in clear, dry weather. At such times radiation fails to cool the ground, and a hot, muggy day may be followed by an oppressive, almost stifling night. It is under such conditions that our most oppressive summer weather comes. Summary — Tlie air is warmed someichat by the nassaqe of heat rays through it, but far more by conduction from the j 'ound, and by convection. It is cooled by radiation, and by condttcMon from the ground. Vapor and dust interfere ivith radiation. EARLY MORNING Fig. 392. —To show that the sun's rays pass through more air when the sun is low in the heavens than when it is high. every 300 feet. There is no warm ground to impart heat ti, these upper layers of the atmosphere ; and warm air, rising from the surface, expands and cools as it rises. Because the upper air is so cool, a frigid climate is found at the equator Fig. 394. — To show that near the poles the sun's rays reach the earth in a more slanting way, and after passing through more air, than at the equator. cooler than neighboring lowlands. That air cools on expanding may be proved by a bicycle pump. Air pumped into the tire is compressed, or made more dense, and therefore warmed. When this compressed air is allowed to escape, it expands and cools, and its coolness may be felt. Although surrounded by cold air, parts of highlands exposed to direct rays of the sun may become quite warm at midday. On a high mountain one may, therefore, be very warm in a protected, sunny place, while a few feet away, in a shady spot, or one exposed to the wind, it is very cold. Radiation is so rapid in the clear, thin, upper layers of air that even the warm places quickly cool off when the sun disappears ; in fact, the temperature may rise to 90° at midday and descend to 10° at night. Summary. — Highlands are coole: than loidands, the temperature changing about 1° for every 300 ftet. There is no warm land to warm the upper air, and air cools as it rises and expands. Rapid radiation in the clear, thin air causes cold nights. (C) Other Reasons for Differences. — We have already learned several reasons for differences in temperature according to situation; for example, nature of rock, exposure (p. 237), and influence of water bodies (p. 238). The nature and direction of the wind also influence temperature (p. 265). These causes for differences in temperature are more fully studied in Chapter XIV. terfere with the normal daily range (Fig. 396). A cloudy sky, interfering with the passage of the sun's rays, may prevent the temperature from rising after day to night differs from time to time and from place to placa Thus the range is great when warm days are followed by cool nights, and less when cool days are followed by cool nights. The daily range in winter is quite different from that in summer ; it is different at the equator from what it is in temperate latitudes ; and on the land from what it is at sea (Fig. 397). Summary. — In the normal daily range the temperature is highest after midday, and lowest just before sunrise. The amount of daily range varies from time to time and from place to place. for the same reason that the hottest time of day is after noon. While there is a normal seasonal curve as described, it differs greatly in various parts of the world (Fig. 398). For example, the midwinter temperature at the equator is very high, in the frigid zones very low; the range over the equable ocean is far less Fig. 398. — Seasonal temperature range in several places. (1) St. Vim-ent, Minn. ; (2) New York State ; (3) Yuma, Ariz. ; (4) Key West, Fla. ; (5) Galle, India; 4 and 5 are near the equable ocean. than that over the land ; in the southern hemisphere the lowest temperature comes at the time of our summer. There are also differences caused by altitude, deserts, and other influences. Summary. — TJie average temperature rises until after midsummer and descends until after midwinter. The normal curve of seasonal temperature range varies from place to place. FORMS OF WATER. 169. Humidity. — Water vapor, which rises from the ocean, and all damp surfaces (p. 230), is dilTused through the air and drifted about with it. It finds its way to all parts of the earth; not even the Sahara has absolutely dry air. The actual amount of vapor in the air, that is, the amount in pounds or quarts, is known as the absolute humidity. If there is as much as possible, the air is said to be saturated. For example, in a room 10 x 20 x 20 feet, the air at a temperature of 80°, if saturated, has Q\ pounds of water in the form of vapor. This is its absolute humidity. To represent the amount of vapor present in air, compared with the amount that might be there, the term relative humidity is employed. Relative humidity is measured in percentages. Thus the relative humidity of saturated air is 100 per cent, for it has all it can contain ; of absolutely dry air, 0 per cent ; and of air having only half as much as it might carry, 50 per cent. If the relative humidity is low, as in deserts, there is a chance for so much more vapor in the dry air that evaporation is rapid ; if the humidity is high, as in the tropical forest, there can be little evaporation, and surfaces remain damp. We notice this difference in summer, for some days are clear and dry, others are humid or muggy. When the humidity is great, the weather is most oppressive ; we perspire easily, and are very uncomfortable, because there can be little evai;)oration from the surface of the body. AUG. 14 15 16 17 18 19 AUG. 20 1893 Fig. 391). — Daily changes in relative humidity at Ithaca, N.Y., for one week. Notice that at night the humidity rises nearly or quite to the dew point (100 per cent), but in the warmest part of the day is very low. This does notanean any change ic the absolute humidity, but is the result of changes in temperature from day to night Warm air can carry more water vapor than cool air, for the amount of vapor possible depends on temperature. For this reason, when the temperature in the room mentioned above is 60° there can be only S^ pounds of water vapor in the air. There is, therefore, far less vapor in the frigid than in the tropical zone. From this it is evident that if saturated air is warmed, it ceases to be saturated ; that is, its relative humidity falls (Fig. 399) and evaporation is possible. This is illustrated by the Sahara. There the winds are blowing toward a warmer region, and the relative iiumidity is being constantly lowered, making the air so dry that the ground is dried and a desert produced. If, on the other hand, damp air is cooled, its relative humidity increases, and the point is soon reached when it becomes saturated. Further cooling then forces some of the vapor to condense to liquid water, or, if the temperature is below freezing, to snow or ice. This is known as precipitation. These facts explain many phenomena. Thus, when one breathes against a cool window pane the breath is cooled to the point of saturation, and some of the vapor caused to condense. A glass of water " sweats " on warm, muggy days, because the cool glass reduces the temperature of the air near it, and raises the relative humidity to the point of saturation. Then some of the vapor must condense. This point of saturation is often called the "dew point," because, when it is reached, dew forms on the ground. Precipitation is caused whenever the air is chilled to the dew point. Summary. — Absolute humidity is the actual amount of ivater vapor in the air at a given time; relative humidity is the j^ercentage present compared to what might he present at that temperature. The relative humidity decreases icith rising temperature, and increases with falling temperature. When it decreases, evaporation becomes more rajyid; ichen it increases, if it reaches the point of saturation, or the " dew point,'' there is precipitation. 170. Dew and Frost. — (A) Dew. — At night the lowe\ air is chilled by contact with the ground, which is cooled by radiation. If the air is damp, some of the vapor is then condensed as dew ; and if it is veri/ humid, dew may begin to form even before sunset. The formation of dew is checked (1) when the air is quite dry, (2) when winds stir the air and keep it from reaching the dew point, or (3) when radiar tion is interfered with by clouds. One reason why dew forms so readily on grass is that vegetation is a good radiator and hence cools quickly. Another reason is that there is water rising from the plants, as there is also, to less extent, from the ground. During the day this water disappears by evaporation and is, therefore, unnoticed ; but at night, when the air is saturated, evaporation is so checked that the water gathers on the surface of the leaves and grass. Summary. — Dew is caused (1) by the chilling of air to the dew point hy the cool ground, and (2) by the rising of water from plants. Dry air, winds, and clouds are unfavorable to the formation of dew. (B) Frost. — Frost is not frozen dew, but the solid form assumed when vapor condenses at temperatures below freezing. Even when the general temperature is above freezing, frost may visit some localities. Low, swampy ground is first affected because (1) the air is damper, and (2) air cooled on the hillsides slides down to these low places. Sometimes frost comes so early in the fall that fruit not yet quite ripe is destroyed ; and late spring frosts often do great damage to buds. Such frosts occur during nights when the air is so clear that radiation proceeds readily. Frosts cause the leaves to change color, and finally to fall ; then for a time the trees are dormant, burstin^^ forth into new life with the return of warmth in the spring. Many plants are killed by the first frost, leaving only their seeds, bulbs, or roots to grow the next season. Summary. — Frost is the solid form assumed by condensed vapor at temperatures below freezing. Frosts first occur in loiv, damp places; and early fall and late spring frosts do damage to plants. 171. Fog and Clouds. — (A) Fog. — ^When we breath into '3old air, the vapor of the breath is condensed into particles of water so small that they float, forming a tiny fog. Fog is formed when damp air is chilled in other ways. For example, it often forms at night when the air over low, damp land is chilled to the dew point ; or it may form when two currents of air are mixed, one cool, the other damp and warm. Fogs at sea are often caused in this way. One of the foggiest places in the world is on the path of transatlantic steamers south of Newfoundland. Here the warm Gulf Stream drift and the cold Labrador current are near together ; and winds from one to the other cause vapor to condense into fog particles. Vessels rarely pass the Banks of jSTewfoundland without encountering some fog ; and in it many a boat has been lost by collision with another, or with an iceberg, or by running aground on the shoals. Fog is one of the most dreaded dangers of the sea, and cautious captains reduce their speed, and keep the foghorns blowing to warn other vessels of their approach. In harbors, navigation is sometimes completely stopped by dense fogs. Dust particles, by supplying solids on which the water may collect, aid in the formation of fog. It is believed that the fogginess of London is partly due to the large amount of dust in the neighborhood of that great city. The fog of London is sometimes so dense that it is necessary to stop all traffic on the streets, and even to close the stores. Summary. — Fog is caused by the chilling of air to the dew point, forcing some of the vapor to condense to tiny drops. Dust particles supply solids for the icater to condense on. (B) Clouds. — Clouds are also made by the condensation of vapor. Most clouds are fog or mist, though the highei ones, where the temperature is below freezing, are composed of snow or ice particles. Many clouds, especially on summer days, are caused by the rising of warm, damp air. As the air rises it expands and cools ; and when the dew point is reached, fog particles grow, forming clouds. Clouds are also ca.iised when damp air blows agaiust a cold surface, for exJtinple, a mountain slope (Fig. 400). Still another cause for clouds is the contact of two currents of air, one above the other, one cold, the other warmer and humid. Clouds assume many weird and beautiful forms (Fig, 402). Those that overspread the sky, having the appearance of layers, or strata, are called stratus clouds. They are common during stormy weather, and are usually low in tho sky, often so low that they hide the tops of the hills. Frequently, especially in winter, they cover hundreds of square miles and last two or three days, while from them large quantities of rain fall. The clouds formed by the rising of air on warm summer days are called cumulus clouds (Fig. 402). A flat base, usually several thousand feet above the surface, marks the height at which the rising vapor begins to condense. Extending above this base, sometimes to a height of a mile, are a series of cloud domes which are often very beautiful, especially when lighted and colored by the rays of the setting sun. Cumulus clouds often develop into thunder-heads. A third common type is the cirrus cloud (Fig. 402), which is often five or six miles above the surface. Unlike the other two types, these clouds are made of transparent ice particles ; and they are so thin that the sun shines through them. It is in cirrus clouds that rings around the sun and moon are often seen (p. 233). The cirrus clouds vary greatly, some having a most delicate and beautiful feathery and plumed form. There is every gradation between the three types of clouds. To these intermediate forms compound names are given as follows: cirro-stratus, strato-cirrus, cirro-cumulus, cumulo-cirrus, cumulostratus, and strato-cumulus. The rain cloud is called nimbus. Summary. — Clouds are mode of fog, mist, snow, and ice particles. They are caused by the condensing of vapor from various causes, — rising and expandiyig, bloici}ig against cold surfaces, and contact of cold and warmer, damj? currents. Stratus clouds are low, and spread over large areas ; cumulus clouds rise in domes above a fat base ; cirrus are thin, fleecy clouds high in the air and are made of ice particles. TJiere are many variations betioeen these types. 172. Rain, Snow, and Hail. — (A) Rain, — Fog particlea 111 clouds may grow to such size that thej can no longer float. They then fall as raindrops. The growth of raindrops is due to several causes: (1) continued condensation of vapor; (2) union of fog particles, driven together by currents of air; and (3) union of particles as they fall through the cloud. Thus rain is merely the result of a continuation of the process of cloud formation. If the vapor condenses rapidly, as in summer thunder-clouds, the drops may grow to great size. Kain may evaporate on its way from the clouds ;"':i^ tail to reach the ground. Such streamers of rain, descending part way to the earth, may sometimes be seen in summer. In other cases, rain on its way down may freeze in passing through a cold layer of air, forming sleet. Some sleet is snow that has partly melted, and then frozen before reaching the ground. forming a matted mass ; (3) as the snow falls it is sometimes partly melted in passing through a warmer layer of air. In many cases snow melts entirely, reaching the ground as rain. This is often illustrated in hilly countries, when hilltops are covered with snow while 100 or 200 feet lower, in the valleys, rain is falling. Summary. — Snoivflakes are crystals, built up by the condensing of vapor at temperatures below freezing. They are often broken, matted, or partly melted on the ivay down, becoming irregular. rents. For this reason they are often made of several layers, or shells, of ice. They may grow to great size, and may be kept suspended by the rising currents long after they are heavy enough to fall through quiet air. When they fall, usually at the margin of a storm, they often break window glass and do great damage to crops. Conditions favoring the formation of large hailstones are fortunately not common^ and their effects are confined to very limited areas. Summary. — Hailstones are made of ice, formed by condensing vapor in whirling air currents. They may grow to large size befot^. they fall, then often doing considerable damage. Topical Outline. — 162. Composition of the Ai/. — (A) Oxygen Nitrogen, and Carbon Dioxide: percentage of each ; ar\|,';on; importance of oxygen ; of nitrogen ; of carbou dioxide ; slow combustion in animals ; rapid combustion ; production of heat. (B) Water Vapor : source; evaporation; variation in amount ; condensation. (C) Dust Particles : nature of materials : distribution ; effect on condensation ; microbes. 163. Effect of Gravity. — Cause of weight ; amount at sea level ; reason for not noticing pressure ; density of lower air ; rarefied air; effect; effect of temperature on density of air; movements started by gravity. 164. Light. — Nature of light; speed of passage; combination ot waves ; effect of prism ; refraction ; colors of spectrum ; reflection ; in stances; mirage; rainbow; halos; color of objects; diffraction; blue color of sky ; sunset colors. 165. Heat. — (A) Radiant Energy: heat from a stove; light from a stove; radiant energy ; radiation; radiant energy from bodies in space; effect of radiation on stove; on sun; part reaching earth. (B) Passage of Radiant Energy : diathermanous ; effect of air on heat; effect of dust. (C) Radiation from the Earth: earth as a radiator ; cause of cool nights; of cold winter; difference between land and water; difference in frost. (E) Conduction: in a stove; air, water, and ground as conductors; depth of conduction in the ground. (F) Convection: in water; in air, — near a lamp, near a fire, by heat from sun. 166. Warming of Land, Water, and Air. — (A) The Lands: warming; .^^ss of heat ; day and ni^ht ; tropical zone ; temperate zone ; frigid zone ; lolor of surface; vegetation; exposure. (B) The Waters: comparison with land ; heat of vaporization ; equable climate. (C) The Air: causes for warming; causes for cooling; interference with radiation. 167. Causes for Differences in Temperature on the Earth. — (A) Position of Sun : differences in height ; reasons why sun low in heavens is less powerful; results. (B) Altitude: decrease in temperature; explanation; illustration of effect of expansion; sunny, spots ; effect of radiation. (C) Other Reasons for Differences : rock; exposure; water; wind. 168. Daily and Seasonal Temperature Changes. — (A) Dady Range: warmest period ; coolest period ; reasons ; interference with normal range ; difference in amount of range. (B) Seasonal Range : resemblance to daily range ; coldest period ; wannest period ; reasons ; causes for differences in curve. 170. Dew and Frost. — (A) Dew : cause ; unfavorable conditions ; reason for dew on grass. (B) Frost : cause ; most favorable places ; early md late frosts ; effect of frost on plants. 171. Fog and Clouds. — (A) Fog: the breath; chilling of air; fog off Newfoundland; dangers to navigation; aid of dust particles; 'London fog. (B) Clouds : materials ; causes ; stratus ; cumulus ; cirrus ; intermediate forms; nimbus. 172. Rain, Snow, and Hail. — (A) Rain: reason for falling ; causes for drops ; large drops ; failure to reach earth ; sleet. (B) Snotv : cause ; snowflakes ; frost on windows ; irregularity of snowflakes ; melting of falling snow. (C) Hail: formation; reason for shells of ice ; size; effects. Questions. — 162. (A) What elements make up the bulk of the air? What is the importance of each? (B) What is evaporation ? What difference is there in the amount of vapor in air? What results when it is condensed? (C) What are dust particles? Where are they most common? What are their effects? .164. What is light? What is refraction ? What is reflection ? What ^.henomena are produced by reflection and refraction of light in its passage through the atmosphere? What is the cause of color in flowers? What is the cause of the blue color of the sky? Of sunset colors? 165. (A) What is radiant energy? What is radiation ? What effect is radiation having on the sun? (B) AVhat are diathermanous bodies? Give examples. Why does the sun lose power in late afternoon ? (C) Why does the ground become cool at night and cold In winter? What difference is there in the radiation from bodies? (D) Give ilhistrations of reflection. Give illustrations of absorption. (E) What is conduction ? What effect has it on earth, air, and water ? (F) What causes convection in water? Give illustrations of convection of air. 166. (A) Why is not the ground excessively warmed? What differences are there in the three zones? What other causes for difference are there? (B) State the reasons why water warms more slowly than land. What is heat of vaporization? Compare land and w^ter in winter and at night. What is an equable climate? (C) How is the air warmed? How is it cooled ? Why is muggy air oppressive? 167. (A) Why is the sun less powerful when low than when high? State three important effects of differences in sun's position. (B) Why are highlands cool? Are any parts warm? What is the effect of radiation V (C) What other reasons are there for differences in temperature V 168. (A) When are the warmest and coolest times of day? Why? What causes are there for interference with the normal daily range? For differences in the amount of daily jange ? (B) When are the warmest and coolest times of the year? Why? What reasons are there for differences in the normal seasonal curve? 169. AYhat is absolute humidity? WLat is saturated air? What is relative humidity ? What is the result of raising the temperature ? What is the cause of some deserts? What is the result of lowering the temperature? What causes precipitation? Illustrate. What is dew point? 170. (A) What is the cause of dew? Under what conditions is there no dew? Why is there so much dew on grass? (B) What is frost? Why does frost first visit low, damp places ? What are its effects? 171. (A) What are the causes for fog? What are the conditions on the Banks of Newfoundland? Why? What is the effect on navigation ? What relation have dust particles to fog ? (B) Of what are clouds made ? How are they caused ? Name and describe each of the cloud types. 172. (A) AVhat is the cause of rain ? Why do the drops vary in size ? What is sleet? (B) What are snowflakes? How formed? Why are they often irregular? (C) What is the cause of hailstones? Why do they sometimes grow so large ? Suggestions. — (1) Recall Experiments 1, 2, 3, 4, and 6 of Chapter II, p. 30. (2) Let a beam of sunlight enter a darkened room and notice the dust that it lights. Watch the sky to see if it is sometimes hazy. Is it clearer after a rain ? Why ? (3) By means of an air pump show that air has pressure. The teacher of physics can tell how this is to be done. (4) Obtain a prism of glass from the physical laboratory and allow a ray of sunlight to pass through it in order to study the prismatic colors. (5) Place a stick in water and notice that it appears to bend below the water. This is due to refraction. (6) Heat a brick or a stone and suspend it by a wire. Why does it become cool ? Does the thermometer show rise of temperature when placed near it? Why ? (7) Try the experiment with black and white cloth, mentioned on p. 236, using ice instead of snow. (9) Place one end of a bar of iron in the fire. Does the other end become warm ? Why ? Place an equal bulk of several substances — for example, iron, soil, and rock — on the stove for a short period to test which first becomes warm by conduction. Use a thermometer to determine this. It can also be told by putting a thin layer of paraffin on each, noticing on which it first begins to melt. (10) Study convection in water, using a glass dish with muddy water so as to see its movement. Study the convection of air near a lamp, clouding the air with smoke (this can be obtained W /ighting a piece of cloth) so that its movement may be seen. Explain the principle of a lamp; of a fireplace. How is your schoolhouse ventilated? Does the fresh air come in above or below? Why? (11) Place a brick and a pan of water (as deep as the thickness of the brick) on a hot stove or over a Bun sen burner. Carefully weigh each before placing them there. When the brick has become warm, take the temperature of each at the top. At the bottom. Why is one the same temperature throughout-, the other hot at the bottom and only warm at the top ? Which shows the higher temperature? Why? When cool, weigh them again. Has either lost weight? Why? (12) Do the same with water and soil, leaving a thermometer in each and recording the changes. In which does the temperature rise faster ? Which cools faster? (13) Take the temperature at 6, 8, 10, 12, 2, 4, G, 8, and 10 o'clock for one day. Construct a curve similar to Fig. 395. Keep records for a week, and construct curves to see if they are all alike. (14) A seasonal curve can also be made, getting the data from the Annual Repo-rt of the United States Weather Bureau, in wdiich daily averages are given for many places. (15) With a bicycle pump illustrate the warming of air by com.pression, and cooling by expansion (p. 241). A little fog can be produced by j)lacing a dish of hot water where the escaping cool air passes over it. (16) Make observations on condensation, — blowing on a cold window, for example. In warm, damp air, watch drops collect on a glass of ice water. That the water does not come from within the glass may be proved by placing a glass, without water, on ice until it is cold, then putting it in the room. The same thing may also be shown by putting salt and ice in a bright tin dipper. The temperature of dew point can be determined by putting a thermometer in the salt and ice, reading the temperature at the moment water begins to cloud the surface of the dipper. (17) Study frost : the time of its coming; the places where it comes first; and any other facts you can find out by observation. (18) For a few days observe the clouds carefully, classifying those you see. Reference Books. — Davis, Elementary Meteorology/, Ginn & Co., Boston, 1894, §2.70; Ward, Practical Exercises in Elemeiilarij Meteorology, Ginn & Co., Boston, 1896, $1.12; Waldo, Modern Meteorology, Scribner's Sons, New York, 1893, $1.50; Elementary Meteorology, American Book Co., New York, 1896, $1.50 ; Russell, Meteorology, Macmillan & Co., New York, 1894, $4.00; Tyndat l. The Forms of Water, Appleton & Co., New York, 1872, $1.50; Illustratice Cloud Forms, U. S. Hydrographic Office, Washington, 1897, $1.00; Annual Reports and Monthly Weather Reviews, U. S. Weather Bureau, Washington ; Bartholomew, Physical Atlas, Vol. Ill, Meteorology, Archibald Constable, London, 1899, $13.00. WINDS. 173. Relation between Winds and Air Pressure. — Winds are tlie result of differences in the air pressure, or weight. It is easier to understand their cause if we consider the atmosphere to be composed of a great number of air columns which gravity holds to the earth. If the sun's heat warms the air in one place, the columns at that place become lighter than in places not so warmed (p. 231). Light air is said to have a low pressure^ heavy air a high pressure^ because tho heavier the air, the higher it pushes the mercury up in the tube of the barometer (Appendix G). The air moves, or flows, from places of high toward places of low pressure, thus causing winds. On a larger scale, it is much the same as the movement of the cooler and heavier air which crowds up the warm, lighter air in a lamp (p. 236). The difference in air pressm^e which causes winds is often known as the barometric gradient. It is so named because the air flows from a region of high pressure, or high barometer, to one of low, as if it were going down a grade, or gradient, as flowing water does. It is not to be understood, of course, that there is a real slope or grade, but merely lighter air in one place than in another. If the difference in pressure is great, the barometric gradient is so high that the air moves swiftly, as water flows down a steep grade. Summary. — Winds are due to a Jlotving of air from regions of heavy air, or high pressure, to regions of low presswe ; and the difference in pressure is known as the barometric gradient. 174. Sea and Land Breezes. — A simple illustration of winds is often found along ocean and lake shores on hot days. On such days the land, and the air over it, become much warmer than the water (p. 288). Soon the heavier air from the water flows in as a cool, refreshing sea breeze, pushing upward the warm, lighter air that rests on the land. When the sea breeze begins to blow, the temperature, which may have risen to 80° or 90°, commences to fall, and the rest of the day is pleasantl}^ cool. It is partly because of the cool sea breezes that so many people go to the seashore to spend their summer vacations. Along tropical coasts, sea breezes are very pronounced and of almost daily occurrence. At night a land breeze often blows out over the water. The reason for this is that the land cools by radiation faster than the water (p. 238), and the cool land air slides out over the sea, pushing up the warmer air that rests there. Sailboats, becalmed off shore when the sea breeze dies down, are able to reach port late in the evening when the land breeze begins to blow. Summary. — Sea breezes are caused by cool air from the seafloiving in on hot days and pushing up the ivarm, light air over the land. At night, land breezes bloic out over the sea from the cooler land. 175. Mountain Valley Breezes. — AYinds similar to the land breezes are noticed at night in hilly and mountainous regions. As the land cools by radiation, the cool, heavy air slides down the slopes, causing winds that often gain great force late at night. During the day, as the valley sides are warmed, the air moves up the valleys ; but this movement does not cause winds so strong as those at night, when the air is flowing down grade and gathering from many tributary valleys into one main valley. and air passing up the valleys during the day causes lighter breezes. 176. Monsoon Winds. — On some of the continents, there are changes in wind direction from summer to winter. These seasonal winds, know» as monsoons, are best developed in Asia Cp- 259)r In summer the land becomes warmer than the watei^ t^iul air, therefore, blows from the Pacific and Indian oceans toward the warm interior, forming the summer monsoon. In winter, when radiation cools the Asiatic highlands, the heavy air moves outward toward the warmer oceans, forming the winter monsoons. Thus twice each year the winds change. In India the changes are so regular, and the winds so steady, that in early times sailing vessels went there in summer and left in winter, in order to have fair winds both ways. All continents show some tendency toward the develoiDment of monsoon winds; but in most cases other winds are too well established for the monsoons to develop perfectly. For example, the regular winds of northeastern United States are from the west ; but they are much steadier in winter than in summer (Figs. 409, 410). The reason for this is that in winter the outflow of cold air from the land strengthens the west winds, while in summer the Inflow of cool air from the ocean weakens them ; but the summer inflow is not strong enouf?h to completely destroy the west wind movement and form regular monsoons. Summary. — Monsoon winds, best developed in Asia, are due to the inflow of air from the ocean to the ivarmer land in summer, and the outflow of air from the cold land in ivinter. 177. Wind Systems of the Earth. — Even greater air movements than those just described are caused by differences in temperature between the warm tropical belt and the cooler zones north and south of it. Tlie winds thus started affect heavier air in other parts of the room crowds in and pushes the warm air upward. There is, therefore, (1) a movement toward the stove ; (2) a rising above it ; (3) an upper current away from it ; and (4) a settling at a distance from it. because of the heated belt of the tropical zone there are similar movements on the earth (Fig. 406). These are (1) a movement of air along the surface toward the equator ; (2) a rising in the torrid zone ; (3) an upward movement away from this zone ; and (4) a settling north and south of it. Summary. — Both in a room heated by a stove, and on the earth, warmed in the torrid zone, there is a movement of air toward the warm place, a rising, an outjlow above, and a settling. (B) Effect of notation. — While air currents in a room move straight toward the stove, the winds of tlie earth are gradually turned from a straight course by the influence of the earth's rotation. Currents of air, like water (p. 191), are turned, or deflected, in the northern hemispliere toward the right, in the southern tow^ard the left. This effect of rotation is therefore called right-hand deflection in the northern hemisphere, and left-hand deflection in the southern. i'lG. 407. — Isobars (lines of equal pressure) for the world. The dark shadmg represents lii^h pressure. The figures (29.85 for example) are inches to which the mercury in a barometer rises, being highest where the air pressure is greatest. In the dark zones of high pressure, the horse latitude belt, air is settling; it moves thence toward the low pressure belt of the warm torrid zone, forming the trade M-inds, and toward the low pressure areas near the poles, forming the prevailing westerlies. WINDS ANJJ STOEMS. 259 Summary. — The effect of the earth^s rotation turns luinds toivard ihe right {right-hand deflection) in the iiorthern hemisphere, and toward the left (left-hand deflection') in the southern. (C) Belt of Calms. — In the torrid zone, where the air is rising, there is little wind, because the air movement is vertical (Fig. 406) instead of horizontal. This is a region of baffling calms, sometimes called the doldrums^ sometimes the belt of calms (Figs. 408-410). This belt does not remain stationary, but, as the belt of greatest heat changes position with the season (Figs. 439, 440), migrates northward and southward. region of calms ivhich changes position with the season. (D) Trade Winds. — The air currents that move toward the belt of calms, known as the trade winds (Figs. 406, 408ilO), blow with great steadiness, especially over the ocean, [ndeed, islands in the trade-wind belts commonly have steep, wave-cut cliffs on the windward side, against which the surf ils ever beating. Instead of blowing directly from the north in the northern hemisphere, and from the south in the southern, the trades are deflected by the influence of rotation, becoming northeast winds in the northern hemisphere and southeast in the southern. These are, therefore, called the northeast trades and southeast trades respectively. As the belt of calms migrates northward and southward each season, the trade winds also change position, being farther north in summer than in winter. F^or this reason, places near the border of the trade-wind and calm belts have alternate seasons of calms and trade winds (Figs. 439, 440). The reason why the monsoons are best developed in Asia (p. 256) is the nearness of the belt of calms. The winter outflow of cold air strengthens the northeast trades ; but in summer, when the belt of calms has migrated northward to the laud, the southeast trades extend across the equator to the land. That i& trades are strengthened and the northeast trades destroyed. Summary. — The steady movement of air toward the torrid zone forms the trade ivinds, which, deflected by rotation, blow from the northeast in the northern hemisphere and the southeast in the southern. These belts migrate northward in summer, southward in winter, (E) Antitrades. — The air that rises in the belt of calms flows northward and southward, high above the earth (Fig. 406). Turned by the influence of rotation, these upper currents, or antitrades^ move from the southwest in the northern hemisphere and from the northwest in the southern hemisphere ; that is, opposite in direction to the lower trade winds. The movement of higher clouds, and of ash erupted from volcanoes, proves this. On high peaks which rise above the trade winds, as in the Hawaiian Islands, the antitrades may be felt. The direction that this whirl of air takes is determined by the influence of rotation ; that is, the air currents are turned toward the right in the northern hemisphere and toward the left in the southern. This causes winds from a westerly direction in each hemisphere. Therefore these wind belts are called the prevailing westerlies (Figs. 406, 408—411). They cover the greater part of the two temperate and the two frigid zones. These winds, as well as the others, are interfered with by various causes. For example, they are often strongest during the daV; because of differences in pressure, caused by the warmth of the sun. When the sun sets the wind often dies down. Storms, sea breezes, and the effects of topograpliy, such as the influence of valleys, also interfere with the force and direction of the winds. Winds are commonly less steady and strong on land than or. water. The reason for this is that the roughness of the land, and its differences in temperature, interfere with their movement Since in the southern hemisphere there is so little land to interfere with the regular winds, the prevailing westerlies are better developed there than in the northern hemisphere (Figs. 408-411). Indeed, in the great Southern Ocean, a vessel can sail eastward around the earth with prevailing fair winds. There is so much land in the northern hemisphere that the westerlies are greatly interfered with ; but high in the air, above the influence of the surface, they blow with great strength and steadiness. Any one can prove this for himself by watching the upper clouds and noticing how uniformly they move eastward, even when the wind at the surface is from the opposite direction. Summary. — Some of the air of the antitrades continues on, forming the circinnjjolar ichirls. Turned by the influence of rotation, these ivinds blow from luesterly directions in both hemispheres, forming the prevailing ivesterlies. They are better developed over the Southern Ocea7i, and high in the air, than at the surface of the northern hemisphere, where they are interfered tvith by irregulaY land and by local winds. in which the air of the antitrades is steadily settling ( Figs. 406, 407). Since the air movement is vertical, tliis is a belt of relative calm, with irregular, unsteady winds, quite in contrast to the steady trades on one side and west winds on the other (Figs. 408-410). As the belt of calms and the trade-wind belts migrate northward and southward witli the seasons (p. 259), the horse latitude belts also shift. STORMS. 1 178. Cyclonic Storms. — (A) Characteristics. — The L'nited States weather map (Fig. 413) shows an area where the aiipressure is light. It is, therefore, called a low pressure area, or a Low (p. 255). Around this center of low pressure the mercury in the barometer stands higher, and this fact is indicated by lines of equal pressure, or isobars. Air is moving conditions, in a low pressure or cyclonic storm area. Describe this diagram. from all directions toward the low pressure area. Next day (Fig. 414) the Low has moved eastward ; but winds still blow toward it, and around its center rain falls. This area of low pressure is known as a cyclonic storm. The following day the storm has moved still farther east (Fig. 415), and, if we should continue to follow it, Ave could trace it out into the Atlantic, and possibly even across northern Europe into Asia. Fig. 413. — Chart to show weather conditions, January 7, 1893. Isobars, heavy lines ; isotherms dotted ; wind's direction indicated by arrows ; areas of rain shaded. Compare with Figs. 414 and 415. blow outward in all directions, while the sky is clear and no rain falls. Such a high pressure area is often called an anticyclone^ because in it conditions are the reverse of those in cyclones. Anticyclones move eastward as cyclonic storms do, even crossing the Atlantic. Fig. 418. — Diagram showing" change of pressure for seven successive days at Ithaca, N.Y. Figures in vertical column indicate inches and tenths of inches of mercury in the barometer. The two drops in the curve were caused by the passage of two low pressure areas. weather. Cloudy weather, rain, and high temperatures usually accompany the lows, and clear, cool or cold weather, the highs ; while the wind direction varies as these areas pass. These high and low pressure areas follow several paths (Fig. 416). Most of them originate either in the northwest or southwest, but some reach the country from the Pacific. In either case, they move toward the east, usually crossing the Great Lakes region, going down the St. Lawrence, and then out to sea. The centers move 500 to 1000 miles a day. Not all low pressure areas are true storms, for those in which the pressure is not very low have light winds and little, if any, rain. These poorly developed low pressure areas sometimes die out entirely ; in other cases they rapidly develop into vigorous storms. It is such irregularities as these that make storm prediction uncertain ; but, because ern hemispheres. They may be compared to the eddies in a river (Fig. 419), that move downstream with the current at the same time that water is whirling from all directions toward their centers. In the same way, while the storm whirls are moving eastward with the prevailing westerlies, the air in them is eddying from all sides toward their centers. Why these eddies develop is not certainly known. One theory is that they are started by the warming of air in some place, causing it to be light and therefore to rise, as air rises over a stove. Opposed to this theory is the fact that these storms are most common and best developed in winter, when heat is least likely to cause low pressure areas. Another theory is that the highs and lows are air waves started in the westerlies. The regularity with which they come, their strength in winter when the west winds are best developed, and other facts, point to this as the more probable explanation. In either case, whether the air is warmed, or whether it is caused to rise and fall in waves, one part will have a lower pressure than another, and toward it air will flow, starting a whirl. Summary. — Cyclonic storms are eddies in the prevailing westerlies, ivith air wliirling toward their ceyiters from all sides. Tliese eddies are low pressure areas, caused either hy the ivarming of air or, more probably, by air waves started in the westerlies. (E) Influence of Cyclones and Anticyclones on Weather. — • WINDS. (See also p. 289.) During the passage of high and low pressure areas the wind changes. On the east side of a storm the wind is from an easterly quarter, on the south side from the south, and between the cyclone and the anticyclone, from the west. The winds do not move along straight lines toward the center, but are turned by the effect of rotation so that they blow spirally ; and if the differences in pressure are considerable, they blow with great force. Near the center the air rises (Fig. 412); but in an anticyclone it is steadily settling (Fig. 417). TEMPERATURE. With these variations in wind direction the temperature also changes. Air from the south is warm, from the north, cool or cold. The settling air of the anticyclones brings to the earth some of the cool upper air. Foi- these reasons, when low pressure areas pass over a region there is usually hot, humid air in summer, and damp air and rising temperature in winter. But when the high pressure areas approach, the air becomes clear and cool in summer, and cold in winter. Radiation through the clear air of an anticyclone cools the ground far more than through the humid, cloudy air which mantles the earth during the passage of a low pressure area. RAIN. When air is settling it is growing warmer, and, therefore, its vapor does not condense. Consequently anticyclones cause periods of dryness. In cyclonic storms, on the other hand, the rising air is becoming cooler, and its vapor is condensing, forming clouds and rain. The cloudy and rainy portions of a well-developed cyclonic storm may covei an area with a diameter of over 1000 miles. There are two other important reasons for rain in these storms : (1) those winds which are blowing from the south are steadily advancing toward a cooler region ; (2) in some places the air is forced to rise over highlands, like the Appalachians and New England. If, in either case, the air cools until it reaches the dew point, some of its vapor condenses. In central and eastern United States the rain-bearing winds of cyclonic storms are mainly from the south and east. Winds from these quarters bear vapor from the ocean, and those from the south are, in addition, blowing toward cooler regions. In New England, well-developed cyclonic storms are commonly called northeast storms, because of the damp ocean winds then blowing from that quarter toward the center of low pressure. When vapor condenses to form clouds and rain, the so-called '' latent heat " (p. 238) is liberated, and this helps warm the air. It is partly for this reason that storms commonly increase in violence in passing over the Great Lakes and the ocean; for in these places more vapor is provided, and the heat from its condensation causes lower pressure and, therefore, a more rapid inflow and rising of air. A cyclonic storm has been called a great engine, furnishing some of its own energy as the vapor condenses. of cumulus clouds appear (p. 248). As the day passes these grow larger and darker, rising as masses of rolling, surging cloud, perhaps a full mile above the level base. Rain finally falls from these clouds, and thunder and lightning are produced. The lightning is an electric spark, passing from cloud to cloud, or from the clouds to the earth, the electricity being produced when the air currents are swirling violently about and the vapor rapidly condensing. Thunder is the noise caused by the spark, and its rolling is the result of echoes among the clouds. Thunder storms are often small, perhaps only a few hundred yards in area ; but sometimes they are 50 to 100 miles long, 15 to 25 miles broad, and 3 to 5 miles high. They travel eastward in the west winds at the rate of 20 to 50 miles an hour, and may last from 2 to 10 hours before dying out. The rain is heavy, the winds often strong, and the lightning destructive. On the borders of thunder storms, hail frequently falls (p. 250). Thunder storms occur in other places where warm, humid air is rising to a level at which its vapor rapidly condenses. For example, they are of almost daily occurrence in the belt of calms. Around mountains, too, as the air rises on a hot day, clouds often gather and develop into thunder storms. In arid lands these storms are sometimes accompanied by so rapid condensation of vapor and so heavy rain that they are called " cloudbursts.'^ Summary. — Tliunder storms are caused by the rising of warm, humid air in loio pressure areas, usually in the southern portion ; they are over-developed cumidus clouds. They also occur in the belt of calms, and where air is rising around mouiitains. (B) Tornadoes. — Tornadoes (Fig. 420) develop in the southern portion of low pressure areas under conditions similar to those causing thunder storms. The warm, humid, lower layers of air, brought by south winds, have above them cooler layers moving from the west. As the lower air warms and rises, a whirl starts around the center of rising, and the winds blow with great force. Like thunder storms, tornadoes often occur in groups, perhaps a score or more developing at one time, and not very far apart. Heavy rain and liail fall at the margin of the whirl, and thunder and lightning occur. The winds of the tornado whirl are so strong that houses are overturned, heavy bodies picked up and carried long distances, trees uprooted, and paths cut through the forest. In the center of the whirl there is a partial vacuum, and, as it passes, the air inside of houses expands with such force as to blow out the windows, and even the walls. The path of great destruction is only a few score yards wide, though it may reach a length of several miles before the tornado dies out. Although the passage of a tornado lasts but a minute or two, its work of destruction is so complete (Fig. 422) that tornadoes are much dreaded ; and, in regions visited by them, holes, called " cyclone cellars," are made in the ground for shelter. Fortunately tornadoes do not occur everywhere. They are especially abundant in the Mississippi valley. In that level, open country it is easily possible for warm, humid air from the Gulf of Mexico to slide in under the cooler, upper air and thus bring about the unstable conditions which are so favorable to tornado formation. They do not develop in arid countries, because the air is not humid enough ; nor are they common in mountainous or hilly lands, because the irregular surface causes a mixture of warm and cool air layers. They rarely occur east of the northerr Appalachians. Summary. — Warm, humid air, creeping under cooler layers in the southern part of low pressure areas, especially on the level p)lains, causes an ^instable condition ; and at times, as the air rises, the in-moving winds start a violent whirl, forming a tornado. (C) Waterspouts. — At sea conditions favoring tornadoes produce waterspouts (Fig. 421). In their center the water is raised in a low cone, and some salt water is actually carried up into the spout. 180. Hurricanes and Typhoons. — Very violent storms, known in the Pacific as typhoons^ and in the Atlantic as hurricanes, develop in the tropical zone and move into the temper- ate zones. On passing into the cooler temperate zones they become larger and less violent, and then closely resemble cyclonic storms. The path followed by the Atlantic hurricanes is usually Pacific and Indian Fig. 425. — Diagram of a hurricane, showing direction of movement (long arrow), rain area (shaded) , and winds eddying toward low pressure center, C. blow (Figs. 425-428), often with such force as to overturn trees and houses. Towns have been devastated and many vessels lost, as at Samoa in 1889, when several war ships were destroyed during a typhoon. Along the Atlantic coast of the United States the most violent storms are hurricanes, which often leave the coast strewn with wreckage. Heavy rains, vivid lightning, and loud thunder accompany these storms. With them also travels a wave of high water, which, advancing on low coasts, causes much destruction, destroying kouses, towns, and life. It was one of these waves, rising over Galveston, that, together with the winds, caused such terrible destruction in 1900, killing thousands of people and almost destroying the city (Fig. 429). Such a wave is due to two causes: (1) drifting of water toward the storm center by the spirally in-blowing winds (Figs. 425-428) ; (2) rising of water in the center because the weight of the air there is less than in the ring surrounding it. Most hurricanes occur in late summer and early fall, because then the belt of greatest heat is farthest north. At the equator, winds are not turned by the influence of rotation ; but, as the distance from the equator increases, they are turned more and more. Whirls can develop only when the winds are turned to one side so as to start a spiral movement around the center of rising. For this reason hurricanes cannot start at or near the equator ; but they can start in the hot belt when it has migrated some distance from it. In the North Atlantic the period when the belt of calms is farthest from the equator is in late summer, and then hurricane whirls start in the rising air. Summary. — Hurricanes and typhoons are violent ivhirls, starting in the torrid zone, and resembling tornadoes, though larger and less violent. They start over the ocean .because of the great amount of vapor, ivhose condensation supplies heat ivhich causes more rapid rising. Their fierce ivinds, and the ivater wave which accompanies them, cause great destruction. They occur late in summer, or early in autumn, when the belt of calms is farthest from the equator, because then the effect of rotation can deflect the winds arid sf,g,rt the spiral movement which cctuses the ivhirl. Topical Outline. — 173. Relation between Winds and Air Pressure.— Air columns; effect of heat; low pressure; high pressure; cause of winds; barometric gradient; strong winds. 176. Monsoon Winds. — Place of best development ; summer monsoon ; winter monsoon ; importance to sailing vessels ; reason for lack of development elsewhere ; condition in northeastern United States. 177. Wind Systems of the Earth. — (A) Comparison with a Stove: air movements in room heated by stove; on earth. (B) Effect of Rotation: right-hand deflection; left-hand deflection. (C) Belt of Calms: cause; doldrums ; migration. (D) Trade Winds : steadiness ; deflection ; southeast trades ; northeast trades ; change in position ; relation of Asiatic monsoons to trades. (E) Antitrades : upper outflow; direction ; proof of existence. (F) Prevailing Westerlies : source of air ; circumpolar whirl ; effect of rotation ; prevailing westerlies ; interference with winds ; westerlies over Southern Ocean; in northern hemisphere; high in the air. (G) Horse Latitudes : location ; settling air ; condition of winds ; shifting of belts. 178. Cyclonic Storms. — (A) Characteristics : low pressure area ; isobars; winds; rain; cyclonic storm ; movement. (B) Anticyclones: pressure; winds; sky; name; movement. (C) Succession of Cyclones and Anticyclones: regular succession; weather changes; places of origin; paths ; weak lows ; iri-egularities. (D) Cause of Cyclonic Storms : comparison with river eddies ; theory of heat origin ; theory of wave origin ; relation of eddies to low pressure. (E) Influence of Cyclones and Anticyclones on Weather: (a) Winds, — variation in direction; deflection; variation in force ; rising air in lows ; settling in highs, (h) Temperature,— south winds ; north winds ; settling air ; passage of lows ; of highs ; radiation, (c) Rain, — reason for dryness in highs; effect of rising in lows; other causes for rain ; source of vapor ; northeast storms ; effect of liberation of heat; storms over water. 179. Thunder Storms and Tornadoes. — (A) Thunder Storms : place of occurrence in low pressure areas ; cause ; growth ; lightning ; thunder ; size ; path; rate of movement ; occurrence elsewhere; cloudbursts. (B) Tornadoes: favoring conditions ; the whirl; comparison with thunder storms; effect of winds; condition in center; path; time of passage; cyclone cellars; occurrence in Mississippi valley; absence in other sections. (C) Waterspouts., 180. Hurricanes and Typhoons. — Typhoons; hurricanes; places of development; movement into temperate zones; paths followed; cause; reason for development over the sea; accompanying phenomena; effects of water wave ; cause of wave ; time of occurrence ; explanation of this. 177. (A) Compare the circulation in a room heated by a stove with that of the earth. (B) in what direction, and why, are winds turned from a straight course? (C) What is the condition in the belt of calms? Why does it change position ? (D) What are the directions of the trade winds? Why? What effect has the migration of the belt of calms? Why are the monsoons so well developed in Asia? (E) What is the direction of the antitrades ? How is this known ? (F) What is the circumpolar whirl? W^hat is the direction of the winds? Why? What are the prevailing 'westerlies? What interferes with the regular winds? How do the westerlies of the northern and southern hemispheres differ? (G) What are the conditions in the horse latitudes ? Why ? 178. (A) What is a low pressure area ? What are isobars ? A cyclonic storm? State its characteristics. (B) What are anticyclones ? Contrast with cyclonic storms. (C) What changes accompany the highs and lows ? What paths are pursued? What irregularities are noticed? (D) Compare cyclonic storms with eddies in a river. State the two theories for these storms. What facts favor one rather than the other? (E) What is the nature of the winds in high and low pressure areas? What changes in temperature occur as these areas pass over a region ? What are the causes of rain in the cyclonic storms? Why do storms commonly increase in violence when passing over large water bodies? 179. (A) Under what conditions do thunder storms appear in low pressure areas? Why? What is the lightning? The thunder? What are the characteristics of these storms ? Where else do thunder storms occur? (B) Under what conditions do tornadoes develop? What are some results of tornadoes? Where are they most common? Why? In what situation are tornadoes rare? (C) What are waterspouts? 180. What are hurricanes? Typhoons ? What paths do they follow ? WTiy do they start over the sea? What destruction do they accomplish? Give instances. What destruction is done by the water wave ? What is the cause of this wave? When are these storms most common? Why at that season ? Suggestions. — (1) Recall tlie previous experiments on convection (Chapter XII, 10). (2) Open a window on a cold day when no wind is blowing. Why does the cold air enter the room? (3) Keep a record of the wind direction for twenty days. How many days did the wind blow from each of the four quarters (north, east, south, and west) ? For the same period keep a record of the direction that the higher clouds are moving. How many days do they move from each quarter ? (4) On an outline map make a sketch of the winds of the globe similar to Fig. 408. Make a sketch to show the change in position of the belt of calms (Figs. 439, 440). (5) If the instruments are available, keep a record of the wind direction and force, humidity, temperature, clouds and rain, and barometric pressure (Appendix G). Tell when cyclonic storms and anticyclones are passing, and carefully record the relation between air pressure and the other phenomena. From your observations predict the weather for the following day. (6) Study weatlier maps (Appendix H). (7) With apparatus obtained from the physics laboratory make an electric spark. This is a lightning flash on a small scale, and the noise is thunder. A similar flash and noise may often be noticed as a trolley car passes. (8) If thunder storms occur, keep a record of all the phenomena and report upon them. (9) Read, say in Harper's Wp.ekly for the autumn of 1900, an account of the destruction of Galveston. Be on the outlook next fall for newspaper reports of hurricanes or typhoons; also, next summer, for reports of tornadoes. Reference Books. — Harrington, Rainfall and Snoiv of United States, Bulletin C, U. S. Weather Bureau, Washington, D.C., 1894; Ferrel, Popular Treatise on the Wind, Wiley & Sons, New York, 1889, $4.00; Finley, Tornadoes, Hine, New York, 1887, $1.00. (See also references at end of Chapter XII.) WEATHER AND CLIMATE. 181. Difference between Weather and Climate. — Weather refers to daily changes in temperature, wind, clouds, and rain. Climate is the average result of these weather changes. For example, certain parts of the tropical zone are said to have a rainy climate. This does not mean that it rains every day, but that, though the weather on some days is clear, on still more it is rainy. Thus the average condition, or the climate, is rainy. The following are some of the more important kinds of climate: dry, hot desert climates; hot, rainy climates, as in the belt of calms; damp, equable ocean climates; extreme and variable climates, common in the interior of continents; and frigid climates. The greater part of the United States has a variable climate. These different climates, and the reasons for them, can best be understood by studying the conditions in various parts of the world. Summary. — Climate is the average of iceather, ivhich is the daily condition of temperature, ivind, clouds, and rain. There are a number of very different climates on the earth. 182. Zones of Heat. — (A) The Five Zones. — The most widespread cause for variations in climate is the distribution of sun's heat from equator to poles. This results from the differences in angle at which the sun's rays reach the earth in different latitudes (p. 239). From this has arisen the common division of the earth into five climatic zones, — two frigid, two temperate, and one torrid, or tropical (Fig. 430). ing influences. Summary. — Oiving to the angle at ivJiicJi the su7i^s rays reach different latitudes, the earth may be divided into foe zones; but, for a number of reasons, the actual boundaries of the zones are irregular, (B) Influence of Altitude. — One important cause for irregularities in the boundaries of the heat zones is altitude. The climate of highlands is cooler than that of neighboring lowlands (p. 240). The isothermal charts ^ (Figs. 431-434) show numerous cases, as in the Rocky Mountains, where the isotherms are bent toward the equator in crossing higlilands. The influence of altitude is also well shown along the Pacific ^ An isotherm is a line connecting places having the same average temperature. An isothermal chart is one showing these isotherms for a given area (as the world, the United States, or a state) for a certain period of time. A chart for the year has isotherms passing through places whose average temperature for the year is the same ; a chart for January averages all thtj temperatures for that period, etc. slope (Fig, 433), where winds from the equable ocean blow upon a rising coast, with mountains extending north and south. Along this coast the climate is warm and equable ; but on the mountain slopes the temperature descends. Therefore the isotherms extend north and south instead of east and west, as is commonly the case. Summary. — Highlands are cooler than neighboring lowlands. Tlierefore highlands cause the isotherms, or lines connecting x)laces having the same average temperature, to extend irregularly. (C) Influence of Water. — Distance from water (p. 238) is another cause for variation in temperature. Oceanic islands have cooler summers and Avarmer winters than the mainland in the same latitude ; and seacoasts have more equable climates than interiors. This is clearly illustrated by comparing the isotherms in the interior and on coasts of continents. Examine Figs. 433 and 434, for example, to see how much difference there is in January and July between Minnesota, the state of Washington, and Nova Scotia. Find other illustrations on the world charts (Figs. 431, 432). Study the chart of temperature range (Fig. 435) to see where there are great and small ranges. Contrast the range over the Atlantic with that over Asia and America ; and the range over the Southern Ocean with that over the lands of the northern hemisphere. than the interiors of continents. (D) Influence of Winds. — The influence of winds in causing irregularity in the isotherms is best illustrated, on a large scale, where winds blow from water upon land, as in northwestern United States and Europe (Figs. 431-434). In these places the prevailing west winds, influenced by the water over which they pass, moderate the cold of winter and the heat of summer. It is for this reason that in western Europe agriculture thrives, and large cities are found in latitudes that, in eastern North America, are frigid and almost uninhabited. London is in the same latitude as southern Labrador, and St. Petersburg as northern Labrador. For the same reason, the January temperature at San Francisco is the same as that at Charleston, S.C. (5° farther south), while the July isotherm is that of Halifax (6° farther north). Summary. — Prevailing winds iiifluence the temperature, the most pronounced influence being where winds from the ocean prevail, thus carrying the equable temperatures of the water upon the land. (E) Influence of Ocean Currents. — Ocean currents and drifts bear water from one zone to another (p. 193). Winds blowing over these currents have their temperature influenced, and, blowing upon the lands, bear to them some of the warmth or cold brought by the currents from other zones. This effect of ocean currents is well illustrated in the North Atlantic (Figs. 320, 431, 432). The great northward bend of the isotherms off the European coast shows the influence of the warm west wind drift (Fig. 338). This influence is least noticeable in summer when the sun has warmed the surface water. Off iiorthea^stern North America, the cold Labrador current bends the isotherms toward the equator. Therefore, the isotherms are crowded together on the American coast and spread apart, fanshaped, on the European coast. In other words, there are much greater differences in temperature in a short distance in eastern America than in western Europe. Notice also the influence of ocean currents on the isotherms along the west coasts of the United States, South America, and Africa. Summary. — Ocean currents warm or cool the air over them ; moving as ivinds this air transfers the influence of the currents to the land. Tliis is ivell illustrated in the North Atlantic, (F) Influence of Topography. — Hills and valleys have an effect of a local nature on climate. Mountains produce far more widespread effects. By shutting off winds, mountain barriers influence the climate of places behind them. Thus, while the Pacific slope of United States has an equable climate, the country farther east, being cut off from ocean winds by the mountains, has hotter summers and colder winters than the coast lands. The subtropical climate of Italy, southern Spain, and France is partly due to the influence of topography. The waters of the Mediterranean are warm ; the Alps and other mountains shut out the cold north winds; and they interfere with south winds which might bear away warmth from the Mediterranean. Therefore, in this region, oranges and palms grow (Fig. 443) in the latitude of Boston, New York, and other places in the United States which are visited by killing frosts for several months of the year. CLIMATIC BELTS OF THE TORRID ZONE. 183. Belt of Calms (Fig. 408).— The vertical position of the sun in the equatorial belt of calms (p. 259) causes the climate to be hot (p. 240). This belt is also a very rainy The weather of the belt of calms is monotonously uniform. On the ocean, or on oceanic islands, the air grows warmer each day after the sun rises ; and from the clouds which form, and which often develop into violent thunder storms, heavy rain falls. During the night the humid air is still warm, for there is not enough radiation to cool it. Both day and night there is an absence of steady winds, and sailing vessels are often becalmed for days. These conditions are repeated with marked regularity. there is little need for doing so, since, with little labor, the forest plants yield abundant food. For these reasons the tropical forest is inhabited by races depending directly upon nature for food, who, having little ambition for improving their condition, have made little progress toward civilization. Summary. — The belt of calms has a hot, Jiumid climate tvith a general absence of winds. TJie heat and humidity cause a ranh ''jrowth of t7'opical forest, but discourage progress among mankind. the belt of calms the trade winds (p. 259) blow toward warmer regions. Vapor is therefore constantly rising into them, because, the warmer the air, the more vapor possible (p. 244). So much fresh water is thus removed that the sea is made more salt East and West Indies, northeastern Australia (Fig. 437), and southeastern Africa (Fig. 438) have heavy rains, because the trade winds blow upon them from the sea. These places have a tropical forest, resembling that of the belt of calms. Mountainous oceanic islands in the trade-wind belt, like the Hawaiian Islands, have heavy rains on the eastern or windward side while the opposite side has a dry climate. Summary. — East-facing coasts in the trade-wind belts have a rainy climate, because, as the damp air cools in rising over the land, some of the vapor, evaporated from the ocean, is precipitated, 185. Desert Trade- wind Belts. — In the trade-v/ind belts arid conditions are far more common than rainy ; in fact, the trade wunds furnish the most important caune for deserts. They take up vapor in passing over the land for the same reason as on the ocean ; but there is so little moisture to be obtained on land that they become very dry winds, into which belts of Africa. vapor rises wherever possible. This leaves so little water for plants that the land is made desert ; but even in the driest desert air there is some vapor, and rain occasionally falls. In the Mohave desert of Arizona the rainfall is less Africa (Fig. 438), southern South America (Fig. 436), and southwestern United States (Fig. 442); but the largest desert tract is in the great land area of northern Africa and Asia. Commencing in western Africa, there is a series of deserts extending far toward the east coast of Asia (Fig. 444). The great Sahara is a part of this belt. In many places the deserts of the trade-wind belts merge into the arid regions of the horse latitudes (p. 261). Here also the air is warming, and evaporation, therefore, proceeds rapidly. Life in the deserts presents a far different picture from that in the tropical forest. Only a few species of plants are adapted to life amid the unfavorable conditions, and even these are scattered (p. 342). Therefore, the desert is a barren, open country ; and neither animals (p. 357) nor men (p. 386) find it a favorable place for a home. Deserts are among the most sparsely settled parts of the world. The weather is nearly always dry, the sky usually cloudless, and the winds often strong, blowing sand about (p. 87). Even in the temperate zone the days are warm, and in summer hot. For example, in the desert of southern Arizona, though far north of tne tropic of Cancer, the thermometer sometimes rises to 120^ in the shade. The highest air temperature recorded (127°) was in the Algerian desert. But radiation is rapid in the dry desert air, and at night the ground and air cool so quickly that a blanket may be necessary before morning. Summary. — WJiere air is growing warmer, as in the trade-wind and horse-latitude belts, the climate is dry and the land arid or desert. Most of the deserts are in these belts. Deserts are unfavorable to life, — plant, animal, and human. The desert climate is dry, often ujindy, and hot days are folloiued by cool nights. 186. Savanna Belts. — Between the rainy belt of calms and the trade- wind deserts there is, in each hemisphere, a region, called the savanna belt, that has alternate dry and wet seasons. This peculiar climate is caused by the migration of the belt of calms (p. 259). In the hot season the belt of calms migrates to the savannas and there is heavy rain (Figs. 439, 440) ; but in the opposite season the savannas are under the influence of the drying trade winds. As a result of these changes, the hot season (the time of our summer in the northern hemisphere, and of our winter in the southern) has copious rainfall, and vegetation freshens and grows vigorously ; but in the opposite season the ground is parched, and vegetation withers. The season of drought is too severe for many forms of vegetation, such as trees. Therefore, the savannas are covered with those plants, such as grass (Fig. 491), which are able to survive a period of drought (p. 342). The downes of Australia, the pai'k lands of Africa, the llanos of Venezuela and Colombia, and the campos of Brazil are examples of savannas. Their grass supports large numbers of plant-eatin% animals, upon which flesh-eating mammals prey. Savannas are probably destined to become the most productive and best-settled lands in the tropical zone. The open country favors agriculture, and the drought makes necessary some provision for that season. Being thus forced to industry and thrift, the negroes of the savannas have become farmers and cattle raisers, and are the most advanced blacks of Africa. Summary. — TJie migration of the belt of calms brings abundan.. rain to the margin of the desert trade-icind belt during the hot season^ giving rise to alternate seasons of drought and rain. This makes such regions, called savannas, great pasture lands, well adapted to life. 187. The Indian Climate. — As a result of the influence of tlie monsoons (p. 250), parts of India have a peculiar climate with three well-defined seasons, — the hot season, the rains, and the cool winter. During the hot season, which lasts from April to June, hot, dry winds from the land cause the temperature to rise above 100° in the shade. In June the air becomes calm and the heat almost suffocating, and every one longs for the summer monsoon. When this begins, clouds appear, rain falls, and for a month or two rains are of almost daily occurrence, causing vegetation to grow profusely. A short period of calm follows the summer monsoon, and again the heat is intense ; but cool air from the interior soon begins to flow down toward the sea, and by October the winter monsoon is established. The air is then clear and cool, and by January, in many parts of India, fires are necessary. In February and March a sort of spring visits the land. Vegetation then bursts forth, only to be withered by the scorching drought of the hot season, which postpones the real growing season until the summer rains. So heavy is the rainfall on the mountain slopes that, in places, the soil is completely washed away. The heaviest rainfall in the world is at the base of the Himalayas (Fig. 441). h\ a year there are about 500 inches of rain ; that is, if it should all stand where it fell, it would form a layer of 40 feet. Of this amount about two thirds falls in the five summer month«. On a single day there have been 40 inches of rain, or more than falls in most parts of the United States in a year. Summary. — The Indian climate consists of a hot season (April to Jane) ; a rainy season, during the summer monsoon {June to August) ; and a cool season, during the winter m.onsoon. In jyarts of India the rainfall daring the summer monsoon is very heavy, the rainiest pjart of the world being in northern India. G. 439. — Sketch map of winds and rainfall in summer. Zone of greatest heat marked by dots, an imaginary line in the center of this area being the heat equator. m. 440. — Sketch map of winds and rainfall in winter. Compare with Fig. 439 to see nature and effect of migration of wind belts. — (A) Temperature. — The temperature varies greatly from near the tropics toward the poles ; but, excepting near the tropics, there is everywhere a decided difference between summer and winter. Near the polar circles the summers are so cool, and the winters so cold, that the climate is often called subarctic. No trees grow there (p. 340) ; little or no agriculture is possible ; and there are scarcely any human inhabitants, excepting along the seacoast, or in mining camps, like the Klondike. These treeless tundras merge into a forest belt, and vegetation becomes more and more luxuriant until, near the tropics, the climate is so warm that it is called subtropical. In this warm belt cotton, sugar, oranges, and even bananas, pineapples, and cocoanuts are grown. Summary. — TJie climate of the temperate zones changes from, cold, or subarctic, near the polar circles to hot, or subtropical, near the tropics ; and with these changes there are variations in vegetation from treeless tundra to subtropical forest. (B) Rainfall. — The rainfall also varies from north to south. Most temperate regions have a moderate rainfall, decreasing toward the frigid zone and also toward the tropics. The rainfall decreases toward the frigid zone, because there can be less vapor in cold than in warm air (p. 245). It decreases toward the tropical zone because the horse latitudes are naturally arid regions (p. 282). The arid horse-latitude belts, in which are included southern California, southern Texas, Spain, Italy, Greece, and the steppes of Russia, grade in one direction into the deserts of the tradewind belts, and, in the other, into the damp climate of the midtemperate zone. They may be called the belts of steppes. Some parts of the horse-latitude belts, like Florida, have abundant rain- ocean. Some parts, on the other hand, are true desert. Steppes are dry in summer; but some sections are reached by the west winds when they migrate southward in winter, bringing snow and rain. Therefore irrigation is necessary for agriculture, as in Italy, which has dry summers and rainy winters. ' Where best developed, steppes are too dry for trees ; but grass grows in spring, curing to a natural hay during the warm, dry summer, thus serving as a food for cattle. Summary. — The rainfall decreases toward the north because the air is cool ; in most places it also decreases toward the south, andy in the horse-latitude belts, there are regions of arid steppes. (C) Effect of Mountains. — While in southern Europe (p. 279) subtropical plants grow in the latitude of the Kew England and Middle Atlantic States, in our country such plants do not thrivSf even in northern Florida. There are no lofty mountains to prevent cold north winds from sweeping down to the Grulf. Therefore cold waves reach as far as New Orleans and northern Florida., causing frosts so destructive that it has been necessa,ry to give up orange culture in northern Florida. In one respect these cold winds are an advantage, for they are invigorating, and the people of the South do not suffer, as some warm temperate peoples do, :irom the enervating effects of too much warmth. climate from west to east. (A) West Coasts. — The warm, damp winds that blow from the ocean upon west-facing coasts cause a humid, equable climate. This is well illustrated on the northwest coast of the United States and Europe (pp. 278 and 279). While in eastern United States droughts oiten cause the grass V) become parched, the dampness of the air in the Britisli Ireland. The heaviest rainfall in the United States is on the north>vest coast (Figs. 442, 445), where damp air from the ocean Mses up the mountain slopes. There the rainfall amounts to 100 inches a year ; and in winter, when the land is cool, and the westerlies most steady, there is rain, drizzle, or fog almost daily. For the 'same reason there is heavy rainfall on the southwestern coast of Chile (Fig. 444). But in the horselatitude and trade-wind belts, as in southern California and northern Chile, the climate, even on the seashore, is arid. Summary. — On ivest coasts of the tem2:>erate zone, ivhere reached by the prevailing icest iviiids, the climate is damp and equable. The heaviest rainfall in the United States is on the nortJiivest coast. (B) Effect of JSforth-south Mountains. — Along the west coast of Europe there is especially heavy rainfall on the mountain slopes, as in Wales, Scotland, and Norway. But, since these mountains are not very high or continuous, the winds are able to carry vapor far inland, even into Asia. Because of this fact Europe, north of the horse-latitude belt, is well watered and the seat of extensive agriculture. In western North America, on the other hand, as the air rises over the high, continuous mountains, so much of its vapor is condensed that it descends on their eastward slopes as dry air. Accordingly, from the Sierra Nevada-Cascade ranges eastward to the 100th meridian — the part of North America which corresponds in position to Germany, Austria, and eastern Russia — most of the country is arid ; and even farther east, in the Mississippi valley, there are frequent and destructive droughts. Summary. — Western United States differs from Europe in the greater influence of its higher, more continuous mountains, which cause the winds that cross them to reach the other side dry, forming arid, regions as far east as the 100th meridian. (C) Interior of Cojitinents, — The interior of a continent, being far from the sea, receives much less rainfall than a windward coast. Thus there are frequent periods of drought in central western Asia and in central United States. These droughts are less destructive in the northern part, because in a cool climate lighter rainfall suflfices for crops. There are two reasons for this : (1) in cool climates the slight evaporation allows the dampness to remain long in the ground ; (2) melting frost keeps the soil damp for a long time. One striking peculiarity of the interior of continents is the great range of temperature between the warm or hot summers and the very cold winters (Figs. 431-435). During the summer day the temperature may rise above 100° — truly tropical heat ; and in winter it may descend to the Arctic cold of even 40° below zero, giving a range of perhaps 140° in a single year. Minnesota and neighboring states illustrate this extreme, or continental climate. It is also illustrated in central northern Siberia, near the Arctic circle, where moderately warm summers are followed by bitterly cold winters. In fact, this is the coldest known place (Figs. 431, 435), and has been called the cold pole of the earth. It is distance from the sea, and freedom from its influence, that account for the extreme climate of the interior of continents. The land warms in summer, when the sun, though low in the heavens, stays long above the horizon. In winter, on the other hand, the nights are very long, and during the short days the sun is low in the heavens. Under these conditions radiation is far in excess of the heat supplied, and the land becomes exceedingly cold. Summary. — Interiors of continents, being far from the sea, are subject to drought ; and there is great range in temperature, from icarm or hot summers to cold winters. This is known as a continental climate. (D) JEast Coasts. — Since the prevailing westerlies must cross the continent before reaching east coasts, one might expect to find arid climates there. Aridity is prevented, however, by the winds of the cyclonic storm eddies (p. 262), which frequently replace the west winds. Some of these winds blow from the Atlantic or Gulf of Mexico, bringing the vapor which gives eastern United States its abundant rainfall. Because of the influence of cyclonic storms, the climate of east coasts is variable. The west winds are dry and cool in summer, and dry and cold in winter ; but whenever storm winds blow from the sea, both the temperature and humidity are influenced by the ocean. Thus in northeastern United States the east winds are damp and chilly, being cooled in passing over the Labrador current ; and in summer they often bring fogs. The south winds, warmed in passing over the Gulf Stream or the Gulf of Mexico, are warm and damp. From day to day the weather varies (p. 265), one day being like the interior of continents, another like the equable ocean. dant vapor from the sea. 190. — Variable Winds of the Prevailing Westerlies. — Among the winds caused by the passage of cyclonic storms and anticyclones (p. 265) are some so distinctive that they deserve special names. The gentle south wind, which causes oppressively warm weather in summer, and unseasonable warmth in winter, maybe called the sirocco. It is when the sirocco blows that thunder storms and tornadoes develop in summer, and thaws occur in winter. Of the very opposite type are the west and northwest winds that sometimes blow on the rear of vigorous winter cyclones. These cold winds, often filled with snow, are called blizzards in Dakota and northers in Texas. Because of the marked difference in the barometric gradient (p. 255) between the cyclone and the anticyclone the air moves with great velocity, perhaps 40 to 60 miles an hour. The cold, and the fierce snow squalls, often cause destruction of life among sheep and cattle ; even men are sometimes lost in the blinding snow, and frozen by the fierce cold. Milder forms of blizzard occur in northeastern United States. A cold ivave (Fig. 446) is a rapid drop in temperature during the passage of a well-developed anticyclone (p. 263). At such times a wave of cold air spreads over a large part of the country, even down to the Gulf (p. 286). This blanket of air descends from the cold northern interior and from aloft (Fig. 417) ; and since it is, therefore, warming as it spreads out, it is clear and dry. Through it radiation proceeds readily, causing very low temperatures in winter, refreshingly cool weather in summer, and early and late frosts in fall and spring (p. 246). The term cold wave, however, is commonly applied only to the winter condition. northwest, November 27, 1896. Arrows show outward movement of the air. The passage of cyclonic storms sometimes causes an exceedingly warm, dry wind, known as the foehn in the Alps and the Chinook in the Rocky Mountains. These winds are caused by the rapid passage of air across mountains toward a storm center. As the air rises on one side it loses much of its vapor, descending as dry air on the opposite side. It descends so rapidly that it is warmed by compression, as the air in a bicycle pump is warmed (p. 241). This warming lowers the relative humidity (p. 244) until the air becomes very dry ; in fact, the Swiss formerly believed that the foehn came from the Sahara. In the warm, dry air, snow disappears rapidly, and houses become so dry that fires are greatly feared. Whole villages in Switzerland have been wiped out by fire during the foehn winds. Summary. — A sirocco is a ivarm, gentle south wind blowing tovmrd a cyclonic storm ; a blizzard, or norther, is a fierce, cold wind, ivith squalls of snow, in the area between yjell-defined cyclones and anticylones ; a cold ivave is the outspreadiyig blanket of cold air in an anticyclone ; the foehn, or chinook, is a ivarm, dry mountain wind made ivarm and dry by rapidly descending the mountain slopes in its passage toward a low pressure area. 191. Weather of Eastern United States. — (A) Summer Weather. — The typical summer weather of eastern United States may be illustrated by the following actual instance. A cool, dry, gentle west wind is accompanied by a day of agreeable warmth, a night of refreshing coolness, and a nearly cloudless sky. An anticyclone is passing over the region, and following it is an area of moderately low pressure. As this approaches, the wind veers to the southeast, the temperature rises, the air becomes more humid, and both day and night are muggy and oppressive. On the morning of the second day, clouds fleck the sky, in the afternoon growing to thunder-heads. About four o'clock a thunder storm appears, preceded by a fierce squall ; then comes heavy rain, accompanied by vivid lightning and crashing thunder. After the storm, a west wind blows and, as another anticylone passes, the air is again dry and refreshing. This cycle is repeated with some regularity, though there are numerous variations.. At times the low pressure areas are so poorly developed that for several weeks little rain falls. There is then a drought, during which streams and wells run dry, vegetation withers, and crops suffer. At other times a low pressure area is so well developed that, instead of scattered thunder storms, there is general cloudiness and rain. This is especially true in late summer and early autumn, when hurricanes, accompanied by strong winds and heavy rains, pass up the coast. Summary. — Summer weather in eastern United States is variable, being warm and oppressive, often with thunder storms, ivhen south winds blow toward moderately developed areas of low pressure, and cool and refreshing when anticyclones pass. The wind varies in velocity (p. 265) and veers through various quarters, bringing chilly air from the north or east, warm air from the south. While the south wind is blowing a thaw may set in, and, even in midwinter, rain may fall as far north as Canada. A thaw is often followed by a decided drop in temperature as the next anticyclone approaches. Few climates of the world are so variable as these of the stormy west-wind belts ; and the changes in weather are very trying to the health. Consequently many diseases, such as pneumonia, grippe, and consumption, are common in these severe climates. Summary. — The winter weather of the west-wind belts is exceedingly variable, being cold daring the 2Jassage of anticyclones, and relatively ivarm during the i^assage of cyclonic storms, whose south winds may even cause midicinter thaics. 192. Climate of the South Temperate Zone. — Owing to the fact that there is so much water in the southern hemisphere, the changes in temperature are less extreme there than in the northern hemisphere (Fig. 435) ; and the winds blow with more strength and steadiness than over the irregular lands (p. 261). Otherwise the climates of the two temperate zones are much alike. Over the Southern Ocean the summer weather is damp and chilly, the winter raw and cold, though without extreme changes from warm to exceedingly cold weather. Storms are frequent and fierce, and this is why rounding Cape Horn is so dreaded by sailors. Summary. — Excepting for stronger, steadier winds, more uniform coolness, and less decided changes in temperature, the climate of the south temperate zone is similar to that of the north temperate. 193. Arctic Climates. — (A) Near the Circle. — In summer, when the sun is above the horizon both day and night, the air, though cool and sometimes raw, is never very cold. The warmth melts the frost to a depth of two or three feet, making the soil damp and swampy. Then the grass becomes green, flowers blossom, and birds and insects appear. ~ As in other places visited by the westerlies, storms appear in fairly regular succession, bringing rain or squalls of snow. Fogs are common on the sea and along the coast, where damp winds are chilled in passing over cold water. In the late summer, when the sun commences to set, the days grow cooler and the nights cold. Insects disappear, birds move southward, and the land is covered with snow. The soil freezes again, and a skim of ice appears on the ocean, growing thicker as the days become shorter. The Eskimo then gives up his kayak and takes to the sledge in search of seal, liis chief food. Finally the sun is absent even at noon, and then the weather, both day and night, is bitterly cold. In winter the principal changes are those accompanying tlie passage of cyclonic storms. Sometimes, even in midwinter, the temperature rises so high that the Eskimo snow houses, or igloos (Fig. 525), begin to melt. With the coming of spring the sun reappears, the snow melts, and the Eskimo abandons his igloo for a skin tent, or tupic (Fig. 524). The sea ice begins to break up and float away, and the Eskimo returns to his kayak for hunting. Then comes the summer day. Summary. — The Arctic summer, near the Circle, is cool, damp, and stormy. In lointer, ivhen the sun is beloiv the horizon even at midday, the ground is frozen and snow-covered, the sea covered with ice, and the weather bitterly cold. (B) Nearer the Pole. — As near the pole as man has gone the climate has been found similar to that just described ; but the Arctic winter night is longer and colder, the summer cooler. Even there the warmth of the summer sun is sufficient to remove the snow from much of the low ground near the coast. In upper Greenland, the northernmost land known, and far north of the highest Eskimo settlements, Peary found flowers blossoming, insects humming, and musk oxen roaming about in summer. The sea which surrounds the North Pole is everywhere covered with ice floes (p. 194), over which Abruzzi, Nansen, Peary, and others have tried to reach the pole. They must make their dash in early spring, because in summer the ice is too broken to cross on sledges, yet not open enough to allow ships to pass through. Consequently those who have tried to reach the pole have gone as far north as ships will carry them, and remained through the cold, dreary Arctic night in order to be ready for an early start. At last Peary overcame the difficulties of ice and climate that had so long baffled explorers, and in April, 1909, reached the North Pole. Summary. — As far north as man has gone, the climate is similar to that Clearer the Arctic Circle, though coolei- in summer and colder in winter, because the sun is lower and longer below the horizon. Plants and animcds live on the northmost known land. In summer the sea ice breaks up so that travel over it by sledge is impossible. 182. Zones of heat. —'(A) The Five Zones: reason for division ; the zones; boundaries. (B) Influence of Altitude: effect of highlands; isotherms; isothermal charts; Pacific slope. (C) Influence of Water: contrast ocean and land ; illustrations ; temperature ranges. (D) Influence of Winds : contrast western Europe and eastern United States ; eastern and western United States. (E) Influence of Ocean Currents : effect on winds ; transference to land ; contrast western Europe and eastern America. (F) Influence of Topography : local influences ; mountain barriers ; western United States ; Mediterranean. 187. The Indian Climate. — Hot, windy season ; hot, calm season ; the rains ; short, hot period ; winter monsoon ; effect of these changes on vegetation ; heavy rains at base of Himalayas. 188. Variation (in Temperate Zones) from North to South. — (A) Temperature ': near polar circles ; near tropics ; vegetation. (B) Rainfall : in the north; in the south; steppes. (C) Effect of Mountains : Contrast southern Europe and United States ; effect on people. 189. Variation (in Temperate Zones) from West to East. — (A) West Coasts : climate of west coasts ; contrast British Isles and eastern United States ; rainfall of western United States ; Chile. (B) Effect of North-south Mountains : western Europe ; interior of Europe ; western United States; country east of mountains. (C) Interior of Continents: rainfall; droughts ; the cool north ; great temperature range ; continental climate; instances; explanation. (D) East Coasts: effect of storms on rainfall ; in causing variable climate ; changes from day to day. 190. Variable Winds of the Prevailing Westerlies. ^ (a) Sirocco nature ; cause ; effects, (h) Blizzards or northers : location ; reason for strong winds; effects, (c) Cold waves: nature; location; cause of cold; effects, (d) Foehn or chinook : location; cause of warmth; cause of dryness ; effects. 191. Weather of Eastern United States.— (A) Summer Weather: (a) typical cycle: anticyclone; warm south winds; thunder storms; anticyclone. (6) Variations from cycle : droughts ; general rain. (B) Winter Weather : regular succession of cyclones and anticyclones ; precipitation ; wind changes; thaws; effect of changes on health. 193. Arctic Climates. — (A) Near the Circle: summer climate; plants and animals; storms; fog; change in autumn; effect on life; winter climate ; effect on Eskimos ; spring climate ; effect on Eskimos. (B) Nearer the Pole : resemblance to conditions farther south ; differences ; life ; sea ice; time of making dash toward the pole. difference. Name some different kinds of climate. 182. (A) Why may the earth be divided into zones of heat? What about the boundaries ? (B) What is the influence of highlands? What is an isotherm? An isothermal chart? What is the condition on the Pacific slope? (C) What differences are there over land and water? Give illustrations. (D) Give illustrations of the influence of winds on climate. (E) How do ocean currents affect climate ? Give instances. (F) What effect has topography on climate ? Give instances. 185. Why are there deserts in the trade-wind belts ? Where are the great desert belts? Why are the horse latitudes arid? What are the life conditions in the desert? What are the weather conditions? 188. (A) What are the conditions near the polar circle? IIow do tlie temperature and vegetation change toward the tropics? (B) How does the rainfall vary from north to south? What are steppes? Where found? What are the conditions there? (C) What is the result of the absence of lofty mountains in southern United States? (A) What is the climate of west-facing coasts? Why? Give illustrations. (B) Contrast central Europe with the arid West. Explain the condition in the United States. (C) What is the condition of rainfall in the interior? Why are droughts less destructive in the north? What are the temperature conditions? Why? (D) What is the cause for rainfall on east-facing coasts? How does the climate vary? Why? 190. What is the sirocco? The norther? The blizzard? What is the cause of each? Their effect? What is the c^Aise of cold waves? Explain the foehn or the chinook wind. What are their effects? 191. (A) Describe a cycle of typical summer weather in eastern United States. What causes variations from this cycle? (B) Describe the win ter weather. What causes thaws? What is the effect of the changes? 193. (A) Describe the Arctic climate in the different seasons. How do these changes influence life? (B) What is the condition of climate nearer the pole ? Why is it so difficult to reach the pole ? Suggestions. — (1) Trace one or two of the isothermal lines across the charts for the United States (Figs. 433, 434) and endeavor to explain the irregularities. Do the same for one or two isotherms in the northern hemisphere of the world charts (Figs. 431, 432). Follow one or two in the southern hemisphere and account for the difference between their regularity and the irregularity of those in the northern hemisphere. (2) Make isothermal charts of the United States and the world, copying^ upon outline maps the isotherms in the book. (3) Study the Appendix on weather maps (Appendix H) and work out the suggestions. (4) Select and study weather maps illustrating cold waves. (5) From a series of three weather maps for successive days, describe the weather changes at a given place — say Boston or Chicago. Write down the temperature, wind direction, etc., for each of the days. (6) Make a record of local weather changes for a week. Write a short description of these changes. (7) Write a description of the climate of your home. Reference Books. — Ward, Hann's Handbook of Climatology, Macmillan Co., New York, 1903, ^3.00; Greely, American Weather, Dodd, Mead & Co., New York, 1888, $2.50; Turner, Climate of New York Siate, Chapter XI, Physical Geography of New York State, Macmillan Co'. New York, 1902, ^3.50; Croll, Climate and Tme, Appleton & Co., New \ :>r'x, 1 890, $2.50. (See also references at end of Chapter XII.) The United States illustrates in many ways the effect of physiographic conditions on the industries and development of the various sections. In previous chapters reference has frequently been made to these influences. These references, with others added, are summarized in this chapter. 194. New England. — New England is a region of very ancient mountains of hard rock, including crystalline gneisses, schists, and granites. These strata are complexh^ folded, and worn by denudation to the condition of hills and low mountains (Fig. 460). It is held by many that this region was worn down to a peneplain (Fig. 171), with here and there a peak, or group of peaks, rising above the general level. Such peaks have been called monadnocks, after Mt. Monadnock, N.H. (Fig. 455), which rises well above the fairly uniform sky line of the surrounding hilltops. After the mountains were reduced to a low hilly condition, there was an uplift of the land, which permitted the streams to sink their valleys into the ancient mountains. This occurred so long ago that, even in the resistant rocks, the valleys have been broadened to the condition of early matu^'ity. The Connecticut valley, in weaker sandstones ai,i shales, has been broadened to a wide lowland (Fig. 86), witn here and there liills of more resistant trap rock, like Mts Tom (Fig. 229) and Holyoke, rising above tlie valley fioor, or other metals. Over all this region the ice sheet spread, rounding the hills and deepening some of the valleys. The residual soil was swept away, and in places, especially on steep slopes, the rock was left bare; but usually it was covei^ed by a glacial soil. This soil varies greatly from sterile to fertile, from thin to thick, and from clayey to bowldery (Figs. 284, 285). Over a large part of New EngUtnd the glacial soil is too thin, or too sandy, or too rocky, for cultivation. Because of the hilly nature of the land, the many steep slopes, and the poor soil, New England is not a good farming country. In fact, the forest has been allowed to remain on large areas (Fig. 189) ; and, for this reason, the more mountainous northern and western parts are among the important forest regions of the country. Under such conditions the farms are necessarily small (Fig. 457), and the area suited to farming is not nearly large enough to supply the needs of the busy manufacturing towns and cities. The great food staples, such as wheat, arejbrought from the West, while New England farms are devoted mainly to the production of vegetables, dairy, and similar products for neighboring towns. The glacial deposits have formed many lakes and turned aside many streams, which now tumble in rapids and falls over ledges which they have discovered. Hundreds of cities and towns use this water power for manufacturing, which stands at the foundation of New England's prosperity. The lakes aid in regulating the water supply. During the glacial period the land sank and the sea entered the valleys, forming a very irregular coast line (Figs. 388, 389), with many bays and good harbors. This irregular coast line is favorable to fishing, one of the most important industries of New England; and it earb^ encouraged sliip building, for which the forests supplied the lumber. The beautifu' many people in summer. The many harbors have encouraged navigation. This navigation aids manufacturing by furnishing a means of bringing raw materials and of removing manufactured articles to places where they are used. Though irregular, the coast is low enough to permit the easy construction of railways; and the broad, mature valleys of the interior are also easily traversed by them. Consequently, railway lines radiate from the leading ports to cities both inland and along the coast. In this respect New England differs greatly from mountainous Norway, where communication between points along the irregular coast must be by boat. that part of the coast which extends farthest into the interior of New England, and it has an excellent harbor. Communication along the coast is possible by rail and boat; the interior is easily accessible by rail; and all parts of the world are open to its commerce. All eastern Massachusetts is tributary to this port, which lies in the center of a semicircle of manufacturing towns (Fig. 454), one of the busiest manufacturing regions of the world. PHYSIOGRAPHY OF UNITED STATES. 301 In its physical geography, ISTew England resembles parts of Great Britain and Scandinavia. In each case the coast is irregular, the land hilly, and much of the soil poor. Scandinavia, like the more hilly part of New England, has a large proportion of its area uncleared of forest. It is more mountainous than most of New England, and has little manufacturing ; but its irregular coast has encouraged the development of fishing and shipping. Great Britain pays far more attention to manufacturing than to agriculture, and, like New England, depends upon other sections for a large part of its supply of food and raw materials. Summary. — Neic England is a region of ivorn-doicn, ancient mountains, with hilltops rising to a fairly even sky line, but with peaks and groups of peaks rising above this level, especially in the vjest and north. Many of these are still forest-covered. Tlie valleys are fairlv broad, even in the hard rock, favoring the construction of roads ai»^l railways. The ice sheet has left a glacial soil, tvhich, together with the hilly condition, makes this a poor farming region. There is little miner-al wealth, excepiting building stone. In spite of the genercd absence of raw products, the icater power, due to glacial interference with streams, has encouraged the development of manufacturing; and this has been further aided oy the irregular coast, caused by sinking of the land. TJiis irregular coast is favorable to fishing and to navigation. Of the many manufacturing cities Boston is most favorably situated and is, therefore, the largest. 195. New York. — The physiography of the Empire State is more varied than that of New England. New York may be divided into four quite different regions: (1) the Adirondacks, resembling the more mountainous parts of New England; (2) the low, hilly region of southeastern New York, which resembles southwestern New England; (3) the high, hilly plateau, including the Catskills and southern and western New York; and (4) the plains which border Lakes Erie and Ontario. The ice sheet covered the entire state, excepting the extreme southwestern corner (Fig. 270). Therefore, in various parts of the state, there are moraines (Figs. 273, 274), wash plains (Fig. 275), drumlins (Fig. The basis for the great growth of New York is agriculture, in which it ranks high among the states of the Union. In mineral wealth the state is not especially rich, though building stone, clay, and salt are found in excess of local needs. There is also some iron, oil, and gas, but no coal. However, ^he oil, gas, and coal of Pennsylvania are readily accessible; ^ud the iron of the Lake Superior region is easily brought Uy water to Buffalo. Hence, manufacturing cities have developed wherever facilities for transportation favored their development. Water power, due to glacial action, has also "ided in the growth of many towns and cities. The Adirondacks, like the higher parts of New England, are rugged, mountainous, rocky, and forest-covered (Fig. 188). Water power is used in a series of towns around their base, partly in manufacturing the products of the forest, as in making paper from wood pulp. There are some mineral resources, including iron ; but distance from lines of water transportation renders the stores of building stone, and most other mineral products, of little present use. As in New England, these beautiful mountains (Fig. 299) are much resorted to by sportsmen and summer visitors. The uplands of the Catskills, and the hilly plateau of the south and west (Figs. 145, 465), have a thin and often stony soil. This plateau is, therefore, sparsely settled, and there are large areas that are stiil forest-covered. The valleys, being more level, and having thicker and better soil, are dotted with farms and country villages. The abundance of creameries, for the manufacture of butter and cheese, shows that much of this region is better adapted to pasturage than to grain and other crops. The hills are so difficult to cross, and so sparsely settled, that railways are found mainly in the larger valleys; and it is often a long, roundabout railway journey from one valley to the next. The towns and cities, such as Binghamton and Elmira, are in the larger valleys, usually at points where railways from tributary valleys enter, making these places railway junctions. The level plains along the shores of the Great Lakes have a deep soil, deposited by the glacier and in the glacial lakes (p. 149). These lake-shore plains are among the best farming lands of the East, and the influence of the lake water gives them a climate especially suited to fruit culture (p. 166). From near Buffalo to Home, the Erie Canal (Fig. 458) crosses these plains. Its route is now followed by railways ; and the excellent facilities for transportation have encouraged which have been caused by ice erosion and dams of glacial drift. These valleys and lakes afford opportunities for communication by water, road, and railway with the heart of the plateau country. In early days the Erie Canal was the only great artery connecting this interior with the sea ; but railways are now added to the canal to accommodate the steady stream of trade, between the West, the interior of the state, and the sea. The movement of goods along this route, which has aided in the growth of many towns and cities, has especially favored the cities at the two ends — New York, on the sea^ and Buffalo, on Lake Erie. The unloading of goods at Buffalo and New York, for further shipment, accounts in part for their growth. They are, moreover, supplied with abundant raw material for manufacture and have, therefore, become great centers of manufacturing and of commerce. low divides, thus forming islands which add greatly to the water front. As a result, an inclosed waterway has been formed behind Long Island, opening connection with New England, and another along the Hudson (Fig. 851) into the interior. The latter route, extended to the Great Lakes by canals and railways, has concentrated in New York the shipping of a large part of the interior of northern United States. Thus the growth of New York City has kept pace wj i^h the growth of the interior. The peculiar conditions siirromidino^ this rapidly growing city have made the problem of living there difficult to solve. The harbor is in two states, but the main city is on a long, narrow island. There is no space for the population to easily spread outward Fig. 459. — New York City andsurroundings, showing the submerged channel, which extends offshore from the Hudson to the edge of the continental shelf. Before the land was lowered the Hudson occupied this channel. in various directions from the harbor, as in many cities. Here, development has had to extend up the narrow island and across the channels of the harbor. This has greatly crowded Manhattan Island, and has forced many New York business men to live at a distance, large numbers going across North River to New Jersey or across East River to Long Island. Therefore a number of cities have grown up around the splendid harbor, such as Hoboken and Jersey City, in New Jersey, and Brooklyn, now a part of New York City, on Long Island. The problem of transporting these people is more ,\|p^ semble mountainous New England in physiography and industries ; and the low, hilly region of southeastern New York resembles southivestern New Eyigland. TJie plateau section is hilly, sparsely settled on the uplands, but with better soil, and more inhabitants, in the broad valleys. The lake-shore plains are excellent farming land, and the Erie Canal and the railways which cross these plains have caused the growth of many towns and cities, and made much manufacturing possible. TJie two cities at the ends of this route, Buffalo and New York, have become of special importance. New York having the best physiographic situation of all the cities of the country, and hence becoming its metropolis. above the sea that its streams are young and large tracts are undrained (Figs. 78, 79, 119-121). This coastal plains region is broadest in Florida, and extends up the Mississippi valley, which at its lower end is a filled bay. As it is south of the glacial belt, rapids and falls are practically absent from the streams ; but there are lakes in the irregularities of the raised sea bottom, especially in Florida. Much of the surface is too sandy for farming and is covered with pine forests (p. 73). Other tracts are too damp, some in the South being the seat of rice culture, which requires wet ground. Where the soil is dry and fertile enough, the coastal plains are the seat of important agriculture. There is httle mineral wealth in this belt. Sand and clay are abundant, and in some cases are shipped away ; and at Charleston and in Florida there are important beds of phosphate, which is sent far and wide for use as land fertilizer. The coast is low and often swampy, especially near the rivers, into whose mouths the sea has been allowed to enter, by a slight sinking of the land (Figs. 121, 124, 387). There are some good harbors and some large navigable bays, especially in the north, where the sinking has been greatest. But the moving sands, and the sand bars which skirt the coast (p. 214), make many of the harbors of little use. The larger bays, especially Delaware and Chesapeake bays, admit boats far into the land ; and because of their gentle slope, and the absence of falls and rapids, mau}^ of the rivers are navigable to small boats. Anywhere on the level surface, roads and railways may be built; but the sparseness of settlement, and the general absence of manufacturing, make few railways necessary. The cities are located either on the Fall Line (Fig. 125), along the inner margin of the coastal plain, or at the head or mouth of the bays. Thus, Galveston is on a sand bar at the mouth of a bay ; New Orleans is on the navigable Mississippi at the point where it comes nearest to a shallow bay, navigable in early times by small boats ; Mobile, Savannah, and Charleston are on small bays ; Norfolk is at the mouth of the large Chesapeake Bay. Summary. — TJie level coastal plains extend from New Jersey to Mexico. They are often so swampy, or have so sandy a soil, as to be unfit for agriculture. There is little mineral wealth. TJie low, sandy coast has many navigable bays, due to sinking of the land ; but sand bars iyiterferc loith the entrance to many by ships. The chief cities are on the Fall Line or on the coast, either at the head or mouth of a bay. 197. The Piedmont Belt. — The low, hilly country, from New York to Alabama, between the coastal plains and the Ap]3alachians, is known as the Piedmont belt (Figs. 461, 464, 465). It is an uplifted peneplain, with hilltops rising to a nearly uniform level, and here and there a monadnock standing above the general surface. An uplift has given the streams power to sink their valleys into the peneplain. That this was once a high, rugged, mountain region is proved by the fact that the rocks are intensely folded. Excepting in New Jersey the Piedmont region is south of the glacial belt, and, therefore, the residual soil has not been removed from its undulating surface. This soil is usually deej) and fertile, and, since the climate is favorable and the surface fairly level, this is a splendid agricultural region. It is one of the greatest cotton and tobacco belts, and, in addition, produces fruits and farm crops of various kinds. The Piedmont belt is dotted with towns and cities, and crossed by many railway lines. The Fall Line cities (Fig. 125) are 'along its eastern margin, the two largest being Philadelphia and Baltimore, also near the head of navigation on large bays. Washington is similarly situated. Philadelphia and Baltimore, like Boston and New York, have become great seaports because of good harbors and connection with a productive interior. Being shipping points for the exports and imports of the interior, these cities have naturally become great manufacturing centers. Manufacturing has been further encouraged by the readiness with which coal and iron are obtained. The largest city away from the Fall Line is Atlanta, which, like many other towns and cities of the South, has become of importance as a center for the manufacture of cotton, lumber, and other local products. Atlanta owes its development largely to the fact that it lies at the point of intersection of a number of railway lines, including those that pass around the southern end of the Appalachians. Summary. — Tlie Piedmont belt is an uplifted peneplain, ivith a fertile residual soil and a favorable climate. It is, therefore, an excellent agricultural region, producing especially tobacco and cotton. It is dotted with towns and cities, the largest being on the Fall Line. Among these cities are Philadelphia, Baltimore, and Washington, also at the head of large bays. 198. The Appalachian Belt. — This belt, extending from New York to Alabama, parallel to the Piedmont, may be divided into two parts, — the eastern, or Appalachian proper, and the western, or Appalachian (Alleghanj^) plateau (Figs. recent an uplift that the streams have cut deep valleys. For a long time these rugged, forest-covered belts served as a barrier to westward migration ; and even now, along all but a few lines, they are passed with difficulty. The ridges are crossed by water gaps (Figs. 172, 192, 193, 463, 467), which the trails of the Indians and trappers, tlie wagon roads of the early settlers, and the railways and canals of present-day commerce all have followed. The principal lines of passage are along the Cumberland, Potomac, Susquehanna, Delaware, and Mohawk gaps. This belt includes some of the most sparsely settled regions of eastern United States (p. 84), and is an important timber reserve. It would be still less populous if it were not for two important facts. In the first place, wdiere the rock is soft the valleys have been so broadened as to invite an agricultural population (Fig. 466). This is best illustrated by the broad, fertile limestone valleys of New Jersey, Pennsylvania, the Shenandoah valley of Virginia, and the Tennessee valley. In the second place, the rocks contain stores of valuable mineral (p. 108), the most important being coal, iron, oil, and gas. The coal and iron have been exposed in many of the deep valleys. These conditions have led to the development, not only of mining industries, but of important manufactured. Of the many busy centers of mining and manufacturing the greatest is at Pittsburg and Allegheny, where the ]Monongahela and Allegheny unite to form the Ohio. This point has water connection with a wide area; and the meeting of railways where the valleys come together has added facilities for extensive railway transportation. Therefore iron and other raw products for manufacture are easily obtained, and the manufactures are readily distributed. This favorable situation was caused by the effect of the ice sheet (p. 155). Scranton and Wilkes Barre, farther east in the anthracite coal fields, have also developed into important mining and manufacturing cities. Indeed, all Pennsylvania has had its growth stimulated by its great mineral resources, and especially its coal. Birmingham, Ala., where, within a radius of a few miles, are found abundant stores of coal, iron, and limestone, the three materials necessary for iron smelting. Under such favorable conditions a large manufacturing city has rapidly grown. Summary. — Tlie Appalacliian belt, extending from Neio York to Alabama, consists of{l) true mountains, and (2) a plateau portiori. Both are for the most jiart rugged, sparsely settled, and, over large areas, forested, forming a harrier which ivas first and most easily crossed along the ivater gaijs. Some of the broad valleys are good farm land, and there is much mineral ivealth, especially coal. Tliis has given rise to a number of important miriing and manufacturing centers, of which the Pittsburg-Allegheny region is most important. 199. The Central Plains. — The region that slopes toward the Mississippi river, from the Rocky Mountains on one side and the Alleghany plateau on the other, is for the most part an expanse of level plains (p. 76). This levelness is due to two facts: (1) the rock strata are nearly horizontal; (2) the valleys are mature. In a few places the strata have been disturbed by mountain folding, as in the Black Hills and the low mountains of central Texas, Indian Territory, Arkansas, and southern Missouri (Fig. 461). Around Lake Superior is another low mountain area, a southward extension of the ancient mountain land of central Canada. In so level a country, railwa3^s may be built almost anywhere, though they naturally follow the valleys. These are so broad and open that they are well settled, quite unlike the steep-sided valleys of the Alleghany plateau. The large rivers have so nearly approached grade that they are navigable for long distances. The Mississippi, for example, is navigable for 1000 miles from the sea, as far as St. Paul. The ice sheet covered the northern part of these plains (Fig. 270), filling the valleys with drift and thus making the surface more level (Fig. 292). These glacial deposits have turned many «treams out of their valleys, causing falls and rapids, as in th€ case of the Falls of St. Anthony at Minneapolis. Many ponds and lakes were also formed, as in the low, hilly country of Minnesota, in which there are said to be 10,000. One of the most important effects of the glacier was to make the Great Lakes water route (p. 156) which, supplemented by canals, offers facilities for interior water transportation that are not equaled on any other continent. Continuous water of the greatest of agricultural regions (Fig. 468). The further fact that large sections of prairie were treeless helped in the rapid development of the region. The agricultural products vary with the climate from hardy grains in the North to tobacco and cotton in the South. In the hilly lands and along the rivers, especially in Michigan, Wisconsin, and Minnesota, there is forest, from which much valuable timber is obtained. The western part of this plains region (west of the 100th meridian) has an arid climate (Figs. 127, 129), unfitting it for agriculture without irrigation (p. 287). This part of the Great Plains is the seat of an important grazing industry (Fig. 128). There are great stores of mineral wealth, including building stone, clay, salt, lead, zinc, oil, gas, and coal ; and the copper and iron of the Lake Superior region contribute to the natural resources. The almost unlimited supplies of coal, widely distributed, make manufacturing possible throughout almost the entire ing cities along the large, navigable rivers. The greatest of these river cities are St. Louis, on the Mississippi, near the mouth of the Missouri, and Cincinnati and Louisville, on the Ohio. That the situation of St. Louis, near the junction of two great rivers, is favorable, is shown by its marvelous growth, making it the fourth city in size in the United States. Its position makes it a manufacturing and distributing point for products from north, south, east, and west. Anotlier great industrial community is found at the head of navigation on the Mississippi — the twin cities of St. Paul and Minneapolis. The latter has the further advantage of a fall in the Mississippi, supplying water power. New Orleans, near the mouth of the Mississippi (p. 306), and Pittsburg, at the head of the Ohio (p. 309), are closely related in prosperity to the fertile interior plains, for they ^re in close communication with them by water and rail. Along the lake route many important cities have developed : in Canada, Montreal and Toronto ; in United States, Buffalo, Cleveland, Toledo, Detroit, Chicago, Milwaukee, and the two neighboring cities of Duluth and Superior, besides many smaller places. Each -of these cities profits by the commerce that the water route opens to it; and each is able to receive the raw products of the entire lake region (Fig. 469). Iron, one of the most important of these products, must be brought to the coal fields for smelting, and all lake ports near the coal fields share in the benefit. With the recent wonderful development of the iron region there has been a corresponding growth of the lake ports. Each of these cities has some special reason for its growth at that particular point. Duluth-Superior and Buffalo are at the two American ends of the lake route. Toronto is on a good harbor on the Canadian side of Lake Ontario, opposite the Welland Canal. Montreal is at the head of navigation for large ocean vessels, and at the foot of rapids in the St. Lawrence, around which a canal has been built. Cleveland and Toledo are on good harbors on Lake Erie, and near extensive coal fields. Detroit is on a narrow strait, through which lake traffic must pass, and at a point where railways cross from United States to Canada. It is, moreover, practically at one end of Lake Erie. Milwaukee is on a good lake harbor backed by a fertile country. Of all the cities in this section, Chicago has the best natural site and has, therefore, grown the fastest. It is no accident that it has become the second city of the country in size ; nor is there reason to expect that its growth will not continue. The small harbor, around which Chicago started, was scoured out by the overflow stream of the glacial lakes tliat existed while the ice sheet was melting away (Fig. 280). The city soon outgrew its small natural harbor, but continued to prosper because of its favorable situation. position near the end of a great lake. With other lake ports it shares all the advantages of lake shipping; and, like several of them, it is near coal fields, and in the midst of a fertile agricultural region which supplies raw products and a market for manufactured goods. More than this, it is a natural railway center; railroads from the East swing around the southern end of Lake Michigan to reach Chicago, where they unite with railroads from other sections. For these reasons Chicago has become a great manufacturing and commercial center, being a distributing point for a wide area of country. It is a center of distribution for some products, such as meat products, for cities even as far away as the seacoast. Summary. — The Great Plains region, thougJi mostly level, has a few low mountainous sections. The northern portion was covered hy the ice sheet. Tlie greater part of the plains region is adaj^ted to agriculture; but some of the more hilly portions are forested. Tlie western portion is arid, and hence devoted mainly to grazing. Tlie Plains have great mineral resources, notably coed and iron, and consequently have become an important manufacturing section. Tlie navigable rivers and broad valleys have encouraged the growth of a number of large river cities of tchich St. Louis is the greatest. Tlie Great Lakes water route is even more important for navigation, and hence has a series of large and busy manufacturing cities. Of these Chicago is the largest. This, the second city in the country, has a Jine natural situation at the end of one of the lakes, in the midst of a fertile agricultural country, and near extensive coed fields. 200. The Far West. — This broad area is mainly a great plateau with mountain ranges rising here and there. Both the mountains (Figs. 158, 161, 165, 166, 470, 471) and plateaus (Figs. 137, 138, 141, 476-478) are so young that they ai-e very rugged. Yet there are many broad mountain valleys and extensive areas of level plateau, so that, if the cli.mate favored, this might become much more important as an agricultural region. Over most of this area the climate is so arid tliat the land is suited only to grazing; and vast numbers of cattle, sheep, horses, and goats are raised on the plains, plateaus, and mountain slopes. Parts of Nevada, southern California, and Arizona are true deserts, with too little grass and water even for grazing (Fig. 150). On the other hand, some of the high plateaus and moun\^ain valleys have rainfall enough for agriculture, and many of the mountain slopes and higher plateaus are forested. One very large area, including the northern half of California, western Oregon, and much of Washington, has sufficient rainfall to make it a very important agricultural region. Farming is also carried on wherever irrigation is possible; but, unfortunately, the water supply is lowest in summer. One of the great problems of the future, in which the entire country is interested, is how to store the winter rain and melting snow for use in summer. The government is now at work on this problem, and reservoirs are being built which will supply water to reclaim thousands of square miles of arid land. In this way the West may be made to support a much larger population. The mountain rocks contain great stores of mineral, onlyportions of which have been developed. No part of the world equals this section in the production of precious metals ; and, in addition, much copper, lead, and zinc are obtained. Coal, oil, gas, iron, salt, building stone, and many other mineral products, though found in many places, are not yet produced in large quantities. They are among the undeveloped resources of United States. Scattered through the Far West are many thriving towns and cities (Figs. 133, 190), some engaged in mining, some in manufacturing, and all serving as distributing centers for surrounding sections. Of these the largest are Denver, at the eastern base of the Rocky Mountains, Salt Lake City in Utah, and several cities on the Pacific slope. Denver is a railway center and an important distributing and manufac^ring center for a great mineral section. On the Pacific slope are Seattle, Tacoma, and Portland, manufacturing and shipping points for a productive agricultural country. Their harbors, like that of San Francisco (Fig. 350), have been caused by sinking of the land. The great agricultural and mineral resources of California have made San Francisco a busy manufacturing and shipping center, already ranking in size as the ninth city in the country. With the growing trade across the Pacidc, this city seems destined to take a still higher rank. The Far West is justly noted for its magnificent scenery. No part of the world rivals in grandeur the canyon of the Colorado (Figs. 1, 139, 478) ; in no part of the world is there the equal of the Yellowstone Park, with its hot springs (Figs. 243, 474), geysers (Figs. 244, 473), and canyons (Fig. 480) ; nowhere is there another Yosemite (Fig. 475). But these are only some of the best known of the points of scenic interest in the West. Symmetrical volcanic cones (Figs. 214, 215), rugged peaks and glaciers, and grand mountain valleys (Figs. 57, 66, 472) and lakes, whose surroundings are nowhere excelled in picturesqueness, are found in various parts of the West. Each year the stream of travel toward these centers of scenic attraction increases. The dry climate, unfavorable to agriculture, is favorable to health; and, consequently, many parts of the West — Colorado, New Mexico, Arizona, and southern California, especially — are much frequented. The city of Los Angeles owes a large part of its growth to the number of people who have gone there in - search of a healthful climate. The climate of southern California is so sunny and balmy, like that of the Mediterranean, that, wherever irrigation is possible, the orange grows to perfection. It is one of the most attractive parts of the country. Summary. — Except in the northivestern part, aiid on some high jjlateaus and mouyitain slopes, the plateau and mountain area of the West has a climate too dry for agriculture without irrigation. Much of it is, therefore, essentially a grazing region. TJie building of reservoirs, to store the winter and spring floods for use in summer, is greatly increasing the area of agricultural land. The West is an important mineral belt, being the greatest producer of precious metals in the world. Of the cities, the largest in the eastern Rockies is Denver. On the Pacific slope are several cities, of ivhich Sail Francisco is the largest, hewing a fine location, on a splendid harbor, the outlet of a productive country. The West is iioted for its ivonderful scenery, especially the Colorado Canyon^ Yelloic stone Park, and Yosemite valley ; the arid climate also makes the Southwest a favorite health resort. Topical Outline. — 194. New England. — (a) Surface features: rocks: effect of denudation ; monadnocks; uplift; nature of valleys; mineral products, (b) Farming : glacial soil ; reasons for forests ; small farms ; food supply, (c) Manufacturing: water power; lakes, (d) Coastline: cause for irregulai'ity ; fishing; ship building; summer resorts; navigation ; effect oo manuf actliring ; comparison with Norway, (e) Cities : location; Boston; reasons for growth. (f} Comparison: with Scandinavia; with Great Britain. 195. New York. — (a) General features: four divisions; glacial action ; agriculture ; mineral resources ; manufacturing, (b) Adirondacks : forests; manufacturing; mineral; summer resorts, (c) Plateau region: uplands; valleys; agriculture; railways; cities. (d) Lake plains : cause of levelness ; farming ; Erie Canal route ; cities ; valleys leading into the plateau, (e) Largest two cities : influence of canal ; causes of growth. (/) New York : cause of harbor; water communication with New England ; with the interior ; peculiar situation ; effect on homes ; on transportation. 198. The Appalachian Belt. — (a) Surface features : extent; two divisions; ruggedness; effect as barriers ; river gaps, (b) Industries: lumber ; agriculture ; mineral resources, (c) Cities : Pittsburg and Allegheny ; Scranton and Wilkes Barre ; Birmingham. 199. The Central Plains. — (a) Surface features : extent ; cause of levelness ; mountain areas ; broad valleys ; navigable rivers ; effect of glacier ; Great Lakes water route. (b) Industries: agriculture; lumbering; grazing; mineral resources; manufacturing, (c) River cities : St. Louis ; Cincinnati ; Louisville ; advantages of location of St. Louis ; St. Paul and Minneapolis; New Orleans; Pittsburg, (d) Lake cities: cities on the lakes; importance of situation on the lakes; location of Duluth-Superior; Buffalo; Toronto; Montreal; Cleveland; Toledo; Detroit; Milwaukee; Chicago, — origin of harbor, position, commerce, surrounding country, railway center, manufacturing and distributing center. 200. The Far West. — (a) Surface features: plateaus; mountain ranges. (b) Climate and agriculture: arid climate, — grazing, desert; humid sections, — location, forests, agriculture; irrigation; storage reservoirs, (c) Mineral: precious metal; other minerals, (d) Cities: Denver; Seattle; Tacoma; Portland; San Francisco, — its harbor, region tributary, growth of city, (e) Scenery: Colorado; Yellowstone; Yosemite; other attractions. (/) Health: favorable climate ; Los Angeles. Review Questions. — 194. What are the surface features of the uplands V What is a monadnock ? What is the condition of the valleys ? Why ? What mineral products are there ? What effects had the ice sheet on the soil ? Explain the condition of farming. What effect has this on food supply? What conditions have'favored manufacturing? Explain the irregular coast. Wliat important effects has this coast? Where are the cities located? What conditions have favored the growth of Boston? Compare New England with Scandinavia and Great Britain. 195. What are the four divisions of the state? What effect has the glacier had? What are the natural resources? What is the condition and what are the industries of the Adirondacks? What is the condition on the plateau upland? In the valleys? Where are the cities of the plateau section? What causes the levelness of the lake plains? What are the industries there? What effect has the Erie Canal? What is the condition of the valleys leading into the plateau? Why have cities grown at the two ends of the water route ? What conditions of physiography have favored the growth of New York City ? What effect has the peculiar location of the city on homes? On transportation? 196. What is the condition of the coastal plains? What about agriculture? Mineral wealth? What is the condition of the coast line? What favors internal navigation? Where are the cities? 197. Explain the surface features of the Piedmont belt. What is the condition of agriculture? What accounts for the greatness of Philadelphia and Baltimore? What accounts for the growth of Atlanta? 198. What are the two divisions? What are the surface features? How is this rugged barrier crossed ? What are the resources of the belt? What conditions have favored the growth of Pittsburg and Allegheny? Scranton and Wilkes Barre? Birmingham ? settlement? What effects had the ice sheet? Of what importance is the lake route? What conditions favor agriculture? Where are forests found? What is the condition in the western part? What important mineral resources are there? What conditions favor manufacturing? Locate the three largest river cities. How is the situation of St. Louis especially favorable? What advantages of location have St. Paul and Minneapolis? How are New Orleans and Pittsburg related to this region ? Name and locate the leading lake cities. What general advantages do they share? What especial reason is there for the growth of each? What is the reason for the exact location of Chicago? What special advantages has it? 200. What are the surface features ? What is the general condition of the climate ? What is the effect of this on industry? Where are the humid sections ? Why are storage reservoirs necessary? What valuable minerals are found ? For what is Denver important ? Seattle, Tacoma, and Portland ? What causes the harbors ? What has favored the growth of San Francisco? What scenic attractions are there in the West? In what way is the dry climate favorable? What effect has this had on Los Angeles ? Reference Books. — Powell, Physiographic Regions of the United States, National Geographic Monographs, American Book Co., New York, 1895, $2.50; Shaler, United States of America, Appleton & Co., New York, 1894, $10.00 ; Mill, International Geography, Appleton & Co., New York, 1899, $3.50 ; Tarr Sf McMurry Geographies, Second Book, Macmillan Co., New York, 1900, $0.75 ; Davis, Physical Geography of Southern New England, National Geographic Monographs, American Book Co., New York, 1895, $2.50; Emerson, New England Supplement, Tarr Sf McMurry Geographies, Macmillan Co., New York, 1901, $0.30; Tarr, Physical Geography of New York ^Sto/e, Chapter I, Physiographic Features, Macmillan Co., New York, 1902, $3.50; Same, Chapter XII, Influence of Physiographic Features upon Industrial Development; Whitbeck, New York Supplement, Tarr ^ McMurry Geographies, Macmillan Co., New York, 1901, $0.30 (also other State Supplements to Tarr & McMurry Geographies) ; Kemp, Ore Deposits of United States and Canada, Engineering and Mining Journal, New York, 1893, $4.00; Tarr, Economic Geology of United States, Macmillan Co., New York, fourth edition, 1903, $3.50. RIVERS OF UNITED STATES. Almost the entire United States is tributary to seven large river systems (Fig. 479) and a series of smaller streams, most of which flow eastward or southward into the Atlantic and Gulf. The greatest amount of drainage is into the Atlantic, including the Mississippi, which drains two fifths of the whole country ; next in area is the Pacific drainage ; while a small section drains into the Arctic through the Red River of the North. As has been shown in previous chapters, the river systems have been highly important factors in the development of the country. They have been a source of food ; they have supplied water power ; and they have served as pathways of exploration and commerce. The present chapter considers this subject more specifically. 201. The Columbia. — The Columbia rises on the western slopes of the Rocky Mountains, flows across an arid region, and enters the sea in a region of abundant rainfall. Its length is 1400 miles, and it drains over 200,000 square miles. The lower Columbia is formed bv the union of two rivers, the Columbia and Snake. From the Rocky Mountains to the Cascades, both the Snake from the south and the Columbia from the north flow across a vast lava plateau (p. 125). These rivers and their tributaries have cut young canyon valleys in this plateau (Fig. 476), in some places 2000 to 3000 feet deep, out of which it is impossible to lead the water for irrigation. There are many rapids and falls, including the Shoshone Falls, so that, throughout the greater part of their course, the rivers are unnavigable. Instead of serving as pathways, these canyon valleys are barriers to passage ; but in its lower course the Columbia is an important aid to travel, for it crosses both the Cascade and Coast Ranges, thus opening gaps across these mountains, which a railway follows. Sinking of the land has admitted the tide for over 100 miles, as far as Portland; and navigation by river boats is possible up the river even above the junction of the Columbia and Snake (Fig. 481). Large numbers of salmon pass up this river to lay their eggs, or spawn ; and the catching and canning of these fish is an important industry along the lower course of the Columbia. Summary. — The union of the Columbia and Snake rivers makes a great river system. In their upper parts these rivers occupy canyons in a broad lava plateau, and these valleys are barriers to travel; but the lower river is navigable, opening a pathway across the mountains, and admitting ocean boats for 100 miles, as far as Portland. 202. The Sacramento. — The extensive fertile valley of California (Fig. 114), between the Sierra Nevada and Coast Ranges, is drained by the Sacramento River where it crosses the mountains at the Golden Gate. Sinking of the land has admitted the sea, forming San Francisco Bay and connecting the valley of California with the sea (Fig. 350). The Sacramento is 400 miles long and has a drainage area of about 58,000 square miles. It is made by the union of two rivers which extend along the great valley, — the Sacramento from the humid north, the San Joaquin from the arid south. For some distance each is navigable to small boats. These rivers are fed by short streams from the inclosing mountains, where they occupy canyons. At the base of the mountains these tributaries are building low alluvial fans, and are engaged in slowly filling the great valley (p. 68). Over the alluvial fans the streams flow in shallow valleys, from which water is easily led for purposes of irrigation. The water of the mountain streams is also used in hydraulic mining for washing gold from the river gravels. Summary. — TJie Sacramento, fonned by union of the Sari Joaquin und Sacramento, is fed by small mountain streams whose water is useful for irrigation and. for hydraulic mining. Breakiyig through the Coast Ranges at the Golden Gate, this river connects the great California valley icith the ocean. 203. The Colorado. — The Colorado River, like the Nile, has its source among mountains which supply it with so much water that it is able to flow completely across a vast stretch of arid and desert country. Its length is about 2000 miles, and it drains about 225,000 square miles, being formed by the union of two large streams, — the Grand and Green. For fully half its length the Colorado flows in canyons cut in a high plateau, which in places is over 8000 feet above sea level. The depth of the canyons varies from a few hundred feet to over 6000 feet in the Grand Canyon, which is over 200 miles long (p. 82). At the lower end of the Grand Canyon the country becomes open and the river crosses fully 300 miles of desert to the Gulf of California. In its lower course the river flows over a floodplain and delta. Without exception the Colorado is the most remarkable river in the world (Figs. 1, 139, 477, 478). No other canyon equals the Grand Canyon in size or grandeur. For long distances it is impossible to descend to its bottom over the precipitous sides, and the canyon forms an absolute barrier to travel. It would make an excellent boundary between countries. Only by undergoing the utmost hardships and dangers is it possible to pass through the canyon, and few explorations in America have been more daring than that of Major Powell's party, which made the first descent (Fig. 139). On both sides rise steep, impassable precipices, often from the water's edge ; and the river tumbles over a succession of rapids, in which it is ahnost impossible for a boat to live. Here and there short tributaries enter, with slopes so steep that tlie oncasinnA! heavy rains wash large t)owiders down tbem into the mam streaau. These form one of the chief causes for the rapids. gash in the crnst, and at their base is a buried mountain area, once dry land, now covered by a thick series of sedimentary strata. The river is flowing with so steep a slope that it is rapidly cutting its canyon deeper, and weathering is wasting back the cliffs, which form a multitude of irregular and rugged mesas, buttes, ridges, and spurs. Where hard rocks outcrop, there are steep cliffs ; where water, for throughout most of the area the annual rainfall is less than 10 inches. All the larger tributaries are from the southern and eastern sides, because the river flows so near the edge of the arid Great Basin that tribu. taries from that side must be few and small. These tributaries themselves are in canyons, and between them are broad areas of tableland with many mesas and buttes, — a typical young, arid land plateau (p. 81). in places, a desert country, for a large part of the distance in deep canyons sunk in the 2^latea2(. The Grand Canyon has a depth of 6000 feet. Its steep sides are often impassable, and they are carved and scidptured into a great variety of forms. There are feiv large tributaries, and these bring little icater. 204. The Great Basin. — The Great Basin, a region of interior drainage with an area of over 200,000 square miles, lies between the Kooky and Sierra Nevada mountains. It is bounded on the north by the Columbia plateau, and on the south by the Colorado plateau. A number of disconnected parts unite to form this general basin, one of them. Death Valley, being below sea level. The surface of the Great Basin is crossed by a number of short mountain ranges, known as the Basin Ranges. The entire region is arid, and in places a true desert (Fig. 150). The short, mountain streams quickly disappear, either by evaporation or by percolation into the loose gravels of their alluvial fans. Some of the streams terminate in salt lakes, such as Great Salt Lake ; others in alkali flats or playa lakes (p. 169). There is too little water for extensive irrigation, and, consequently, most of the Great Basin is sparsely settled. The most thickly settled part is the fertile, irrigated region of which Salt Lake City (Fig. 133) is the center. If the rainfall were greater, water would gather in the basins, forming several hundred lakes. During the glacial period, when the climate of the Great Basin was moist, large fresh-water lakes filled some of these basins (p. 164). Summary. — Tlie Great Basin is an arid region of interior drainage, consisting of a number of smaller basins. It is in places true desert, and, for the most j^cirt, sparsely settled. 205. The Rio Grande. — This river resembles the Colorado in some respects. It is almost as long (1800 miles), and has a greater drainage area (240,000 square nnles). Like the Colorado, the Rio Grande receives so large and permanent a water supply from its mountain sources that it is able to flow across an arid country to the sea. Like the Colorado, too, it has cut deep canyons in the plateau ; but they are neither so deep, so long, nor so continuous as the canyons of the Colorado. In a number of sections the valley broadens, and is bordered by floodplains and low, terraced land, over which the river water is easily led for irrigation. Therefore, from Colorado to Mexico, there are many irrigated sections and numerous thriving towns and cities. The only large tributary is the Rio Pecos, which resembles the main river. Owing to the openness of parts of its valley, and the sandy nature of its bed, the Rio Grande loses much of its volume in crossing the arid country and is sometimes dry in summer, But in winter and spring it is a large river, rising especially high during the melting of the mountain snows. It is always heavily charged with sediment, and in places is aggrading its valley. At its mouth a delta is being built, causing a slight bulge in the coast line (Fig. 371). In its lower portion the Rio Grande is navigable to small boats ; but at present this is of little use, since that region is arid and sparsely settled. Summary. — TJie Rio Grande, siqjplied ivith ivater from the Rocky Mountains, Jloius across an arid region to the sea, receiving only one large tributary, the Pecos. Its course is marked by alternate canyons and open valleys, which are irrigated and well settled. 206. The Mississippi System. — This vast river system, the longest and one of the largest in the world, has a length, including the Missouri, of 4300 miles and a drainage area of 1,250,000 square miles. It receives a large number of tributaries, some very long, including the Red (1200 miles long), Arkansas (2170 miles), Missouri (3000 miles), and Ohio (975 miles). Each of these tributaries has large feeders, some of them great rivers; for example, the Platte (900 miles) and the Yellowstone (1100 miles) are tributaries of the Missouri. There are over 10,000 miles of navigable water in the Mississippi system (Fig. 481). The Mississippi valley is a broad depression, a lowland left by the greater uplift of the land on either side. Most of the streams follow consequent courses down the slopes of these uplifted sides. This depression has existed for many ages, at first uplift to dry land plains. As a whole, the Mississippi valley may be considered a mature valley, approaching old age in its lower parts and youth in its upper tributaries, where recent changes have located in the lava plateau of Yellowstone National Park. In many places volcanic accidents and mountain uplift have rejuvenated the mountain tributaries. There are numerous instances where the rivers cut across mountain ranges ; for example, the Missouri in Montana, and the Arkansas in Colorado, forming the famous Royal Gorge of the Arkansas. Like the Colorado and Kio Grande, the western tributaries are supplied with abundant water from the mountains, especially in spring, when they become 20 or 30 times as high as at the low water stage of autumn. Only about one ninth of the rainfall is carried across the arid plains, so much are the streams reduced by evaporation. This water is of great value for irrigation, and, by storage, will make the plains still more valuable. are all muddy. The Platte is so burdened that it is aggrading its bed, and doing it with such rapidity that the river is embarrassed in passing through its own deposits (Fig. 112). The Red Eiver receives its name from the color of its sediment; and the turbid Missouri is often called the "Big Muddy.'' At their junction, the Mississippi has about as much water as the Missouri ; but since it has less sediment, it is able to move down stream that which the Missouri brings. The Ohio drains part of the Alleghany plateau on one side and of the Central Plains on the other. Since the climate of its valley is humid, with a rainfall of over 40 inches a year, the Ohio carries more water than the Missouri. The water supply varies greatly, being least during summer droughts, when the river may be only 2 or 3 feet deep, and most in spring when the snows are melting. It may then reach a depth of from 50 to 60 feet (Fig. 99). The Ohio and most of its tributaries occupy mature valleys; but those in the plateau are deep and steep-sided, dissecting the plateau into the rugged condition of early maturity (p. 84). Throughout most of its course the Ohio is bordered by a floodplain, behind which bluffs rise to a height of 200 or 300 feet. This is an excellent farming country, and the valley is easily followed by railways. The river is navigable even above Pittsburg, though in some places rapids have made canals necessary. The upper Mississippi resembles the Ohio in most important respects. In both cases the valleys have been seriously influenced by the glacier, which has caused rapids and falls. In its headwaters, the Mississippi passes through a series of lakes and swamps of glacial origin. Below^ the junction of the Mississippi and Ohio at Cairo, the Mississippi flows in a floodplain which it is building up because it has more sediment than it can carry down the gentle grade. This floodplain, bordered by low bluffs, is ^bout 600 miles long and from 20 to 75 miles wide. Mem- phis and Vicksburg are situated on the eastern blufp, at points where the river swings against it. Over this immense, fertile floodplain the river swings in a series of meanders, often as much as 5 miles in diameter. These nearly double the length of the lower river. The river is slowly changing its position in the floodplain, and, now and then, the neck of a meander is cut off and a ring-shaped ox-bow lake is left. There are many such lakes which are slowly being filled with sediment. Floods, seepage from the river, and lack of drainage on the level floodplain cause the abandoned channels, or bayous, and other low places, to remain either as lakes or swamps (Fig. 308 ) ; the higher parts are drier and make excellent farm land. At times of great flood, when the river may rise from 30 to 50 feet, the water sometimes opens gaps, or crevasses, in the levees which men have built to confine the river. Then the water tears away the levees, spreading over the floodplain and doing great damage. It is the deposits made during such inundations that are building up the floodplain. Sediment, washed from the slopes of the entire Mississippi system, has built a large delta at its mouth (Fig. 105). This is still growing outward, for each year enough sediment is poured into the Gulf to build a pyramid a mile square at the base and 268 feet high. Most of the delta is too low, level, and marshy for habitation, and over it the river flows sluggishly through a series of distributaries. Sediment is constantly being deposited on the river bed, interfering with navigation, especially at the river mouth. To check this, jetties, or piers have been built at one of th^ mouths, or passes, in order to confine the current and cause it to flow rapidly enough to keep tlie channel open for large vessels. Summary. — The Mississippi, with its many large tributaries, occupies a valley left as a lowland by the greater uplift of the sides. It is, on the whole, mature ; but rejuvenation, by volcanic action and by ujdift, has occurred in many of its headwaters. The tributaries which cross the arid westeryi pjlaiiis are supplied with water from tJie mountains, whicJi is of value for irrigation; they bring much sediment. The Ohio and upj)er Mississippi valleys are mature, have abundant rainfall, and are excellent agricultural regions. They have been affected by glaciation. Below Cairo is 'a broad Jloodplain, betiveen bluffs, and farther down a delta, both made of sediment brought by the river, WJiere dry enough, both are excellent farm land. 207. Smaller Streams of the East. — From the Kio Grande to northern Maine there are a large number of small streams, including the Colorado and Brazos of Texas, the Alabama, James, Potomac, Susquehanna, Delaware, Hudson, and Connecticut. South of the Hudson their lower courses are across the coastal plains, in shallow valleys consequent on the slope of the plains. Sinking of the land has made most of the larger streams navigable in their lower courses. In some cases, especially in the North, where sinking of the land has been greatest, vessels can pass far inland. The importance of this is well illustrated by the Chesapeake, Delaware, and Hudson valleys. From Alabama northward the headwaters of the large streams are either in or west of the mountains. This fact has been of great importance in many cases, since it has opened water gaps into and across the mountains (pp. 309 and 391). North of New Jersey the streams have all been rejuvenated by the effects of the glacier, and their courses obstructed in places by rapids, falls, and lakes, the importance of which has already been pointed out. Summary. — As a result of sinking of the land, 'many of the small streams of the East are navigable in their lower courses ; some furnish openings into and across the Appalachians ; aiid in the Northj glaciatioyi has caused many rapids, falls, and lakes. 208. The St. Lawrence System^ — This remarkable river system includes five of the largest eight fresh-water lakes in the world (p. 162). These are connected by short rivers and straits, in several cases containing rapids or falls, including the wonderful Niagara. The lake basins are very deep (p. 161), the bottoms of all but Erie being below sea level. defined valley, but straggling over a low, hilly land, the higher parts of which rise above the water as the so-called Thousand Islands. From tliis point down to Montreal the river consists of a series of broad, lake-like expanses, with intervening rapids around which canals have been built. The lowest, or the Lachine Rapids, are just above Montreal ; and thence, onward to the sea, there is uninterrupted navigation through a broad valley, into which the tide has been admitted by sinking of the land. Below Quebec the valley is a broad bay, and ocean steamers ascend to Montreal. By means of canals around the rapids and falls, large ships may go on to the western end of Lake Superior (p. 311). The exact preglacial condition of the St. Lawrence system is not yet fully known. It is certainly drowned at one end, and the continuation of its valley, between Nova Scotia and Newfoundland, may still be traced on the sea bottom. When this submerged valley was formed, northeastern North America was more than 1000 feet higher than now, and the mouth of the St. Lawrence was off Newfoundland at the edge of the continental shelf. The inland continuation of this valley seems to have been not the present St. Lawrence, but Ottawa River, the only large tributary of the St. Lawrence system. Above Montreal the system appears to be made of parts of several systems, united by the effects of glacial erosion, dams of glacial drift, and land tilting. These processes have also transformed parts of the valleys into the deep, boat-shaped basins of the Great Lakes (p. 161). Neither the St. Lawrence above Montreal, nor the rivers and straits that connect the lakes, are in preglacial valleys of large streams. Notwithstanding the great volume of water, little erosion is being done along most of the St. Lawrence. The expla^ nation of this is that the lakes, and other quiet stretches, rob the water of its sediment, therefore taking away its erosivo power. Consequently, though young, most of the St. Lawrence streams flow, not in gorges, but in shallow valleys. to this, has peculiar conditions. Leaving Lake Erie clear and free from sediment, the broad Niagara loiters along past Buffalo, almost on the surface of the plain (Fig. 483). At onlyone point in its upper course is there rapid water, where it crosses a ledge of rock near Buffalo. The river divides into two channels around the low Grand Island. The valley is so young and undeveloped that the channel on one side has not been deepened enough to rob the other of its water. Just above Niagara Falls, 15 miles from Lake Erie, the stream is again divided, this time around Goat Island. Here the flow in each branch quickens, and soon the water is tumbling along tumultuously as a series of violent rapids. Then it drops as a great cataract, 160 feet high, divided by Goat Island into two parts, — the larger, or Horseshoe Fall, on the Canadian side, the smaller, or American Fall, on the American side. For 7 miles below the cataract the river rushes rapidly through a gorge 200 or more feet deep, and 200 or 300 yards wide (Fig. 485). In two parts of the gorge there are decided rapids, and at one point a whirlpool. The top of the gorge is at the level of the plain over which the river flows from Buffalo to the Falls; and the gorge cut in this plain reveals its rock structure. It is made of nearly horizontal strata, some hard, some soft, dipping gently southward at the rate of about 35 feet a mile. The upper stratum in the gorge wall is massive limestone (Fig. 482), beneath which is a series of weak shales. It is these strata, also present under the cataract, that make the waterfall possible. The plain ends toward the north in a steep slope, or escarpment (Fig. 485), faced by a plain about 200 feet lower. Emerging from its gorge at this escarpment, the river flows quietly over the lower plain to Lake Ontario. An enormous quantity of water, estimated at 167,000,000 gallons a minute, falls over the Niagara limestone (Fig. 482), which forms the crest of the Falls. The underlying shales are being removed by the swirl of waters, and by FORMATION the grinding against them of great blocks of fallen limestone by a kind of pot-hole action (p. 54). This undermines the limestone, causing huge blocks to occasionally break off, outline of the American Fall has scarcely changed. Long before the cataract has receded to Lake Erie, the southward dip of the shales will have carried them so far into the ground that there will no longer be an opportunity for the river to undermine the limestone. Then the waterfall will disappear. There is clear evidence that when the ice sheet permitted Lake Erie to outflow over the plain toward Ontario, the Niagara cataract was born, falling over the edge of the escarpment. Since then the cataract has receded for seven miles, making the gorge. When the cutting of the gorge first began, the river occupied a broad valley on the upper plain, similar to the present valley above Goat Island. The river gravels and banks made at that time may still be clearly seen on the plain, 200 feet or more above the present river. The gorge could not have existed then. Another proof that the gorge has been cut by river action is the existence of an abandoned fall, similar to the American Fall, at Foster Flats, more than halfway down the gorge. As the cataract receded, it discovered a buried valley beneath the glacial drift ; and where this buried valley leaves the gorge, at the whirlpool, there is a break in the otherwise continuous rock wall of the gorge. The removal of the glacial drift that filled this buried valley has formed the elbow in which the whirlpool is situated (Fig. 485). It was formerly thought that Niagara gave a basis for telling the time in years since the close of the Glacial Period. Three important facts are known: (1) the length of the gorge ; (2) the present rate of retreat of the cataract (five feet a year) ; (3) the cataract began as the ice was leaving. It therefore seemed simple to divide the distance by the present rate; but later studies show that there are many causes for variation in the rate of retreat, of which the following are most important : (1) the limestone is thinner at the northern end ; (2) the time required to remove the loose drift in the buried gorge is unknown; (3) the volume of water has varied ; indeed, at one time Niagara received the waters of Lake Erie only (Figs. 280, 281). Since it is impossible to tell just how much these variations have influenced the rate of retreat, the time that Niagara has taken to cut its gorge is not known positively ; but there is reason for believing it to have been between 5000 and 10,000 years. Summary. — Tlie St. Lawrence system is an immature river system made by the union, largely through glacial action, of parts of a number of rivers. It consists of (1) a drowned lower portion; (2) a middle section with a series of quiet, lake-like stretches arid intervening rapids; arid (3) an upper portion of great lakes, ivith connecttrig straits and rivers, interrupted by rapids and falls. Little erosion is being accomplished because the lakes rob the water of sediment for cutting-tools. Niagara is an exception to this because of the existence of weak shales beneath a massive limestone. At the Horseshoe Fall the removal of these shales is causing the cataract to retreat upstream^ and there is good jrroof that it has receded through the seven miles of the gorge, requiring probably someivhere between 5000 and 10,000 years for the work, which began at the close of the Glacial Period. Topical Outline. — 201. The Columbia. — Climate ; length ; area ; two large branches ; valleys in lava plateau ; effect of these canyons ; lower valley, — crossing mountains, navigation, fishing. 203. The Colorado. — Source of water; size ; inclosing plateau ; canyon valleys; lower course ; Grand Canyon, — barrier, difficulties of passage, rapids, canyon walls ; tributaries ; young plateau. 206. The Mississippi System. — (a) The system : length; area; principal tributaries ; navigation. (b) The valley : origin of lowland ; ancient sea; mature condition; rejuvenation; mountain gorges. (c) Western tributaries: water supply; floods; loss of water; irrigation; sediment, — cause, Platte, Red, Missouri. (d) Ohio: rainfall; floods; mature valley; floodplains ; farming; navigation, (e) Glacial influence : rapids and falls ; upper Mississippi, (f ) Floodplain of lower Mississippi: cause; area; bluffs; meanders; changes in river position; lakes, bayous, and swamps; floods; levees; deposits, (g) Delta: outward growth ; swampy surface ; distributaries ; jetties ; passes. 208. The St. Lawrence System. — (a) Description : lakes ; connection of lakes; Thousand Islands; rapids below the lakes; drowned lower course ; navigation, (b) Preglacial condition : submerged valley ; former elevation of continent ; Ottawa River ; effect of glacier on river; on lakes. (c) Erosion : absence of sediment ; effect on valley form, (d) Niagara : near Buffalo; Grand Island; Goat Island; rapids; two falls; gorge; upper plain ; rocks in gorge wall ; escarpment ; condition below escarpment, (e) Recession of falls : cause of retreat; condition in American Fall ; rate in Horseshoe Fall ; future of falls, (f ) History of Niagara : Review Questions. — 201. What is the situation of the Columbia? Its length and drainage area? AVhat are the two great branches? What is the condition in the upper part ? In the lower part ? 203. State the general features of the Colorado : source of water ; size ; canyons ; lower portion. Describe the Grand Canyon. Why are there few tributaries? What is the condition between them? 205. Compare the Rio Grande with the Colorado. How do they differ? Why is there so much irrigation? How does the volume vary? What is the condition in the lower course ? 206. What is the size of the Mississippi and its largest tributaries? What is the origin and form of its valley ? What is the condition in the headwaters? What is the condition of the water supply in the western tributaries? Of the sediment? What are the principal characteristics of the Ohio? What effects have been produced by glaciation? What are the cliaracteristics of the floodplain : area ; bluffs ; meanders ; floods ; swamps ; farm land ; levees? What is the condition on the delta? 208. What is the general condition of the system ? What is the condition below Lake Ontario ? What was the preglacial condition ? Why is there little erosion? Describe Niagara River. What is the rock structure of the gorge walls? How, and at what rate, is the cataract caused to recede? What will happen as the fall recedes farther ? What proofs are there that the gorge was formed by the river? Explain the whirlpool. What is known of the length of postglacial time ? Reference Books. — Gilbert, Niagara Falls, National Geographic Monographs, American Book Co., New York, 1895, $2.50 ; Tarr, Chapters VII, VIII, and IX, Phijsical Geography of New York State, Macmillan Co., New York, 1902, \|3.50 ; Dryer, Studies in Indiana Geography, Inland Printing Co., Terre Haute, Ind., 1"897, ^11.25 ; Powell, Exploration of the Colorado River, Washington, 1875 (out of print) ; Canyons of the Colorado, Flood and Vincent, Meadville, Pa., 1895, $10.00; Dutton, History of the Grand Canyon District, Monograph II, U. S. Geological Survey, $10.00; Grabau, Niagara Falls and Vicinity, Bull. 45, New York State Museum, Albany, 1901, $0.65, CONDITIONS INFLUENCING PLANT LIFE. 209. Importance of Air. — Without air, both plants and animals die. Carbon dioxide from the air is taken into plant cells and changed to carbon and oxygen, the carbon being built into the tissues. A large portion of the plant tissue is made of carbon, supplied mainly by the air. Air is present everywhere on the earth's surface, even in soil and water (p. 180) ; therefore, as far as this vital substance is concerned, it is possible for plants to be present on every part of the eartli's surface. The fact that there are some places where plants are absent, — for example, underground, in the deep sea, and in central Greenland, — is proof that there are other things of vital importance. of the carbon, of which a large part of plant tissues is made. 210. Importance of Temperature. — Plant activity is impossible where the temperature is below freezing, for then the liquid parts are frozen and cannot move about. In the ice-covered interior of Greenland, therefore, where the temperature is always below freezing, all plant life is absent. Many plants are not injured by being frozen for part of the year, but are able to resume growth when the frost is gone. All plants, even the lowest forms of bacteria, are killed when subjected for a short time to temperatures near the boiling point. This is because such heat causes changes in their tissues which destroy their power of action. DISTRIBUTION OF PLANTS. 337 A low form of plant lives on the lower parts of the Greenland glacier, being frozen all the year excepting a few weeks in summer, when it lives in ice-cold water. These instances show that plants may become adapted to very unfavorable surroundings. They could not live under any other conditions ; yet no other plants could live where they do. Summary. — Even the loivest plants are unable to live where the temperature always remains below freezing, or where it rises to the boiling point even for a short time; but many survive a period of freezing, and some live in the tvater of hot springs. 211. Importance of Sunlight. — Sunlight is also of vital importance to plan-ts, for by its aid the green cells change carbon dioxide to carbon and oxygen. . The branches and leaves of plants are, therefore, arranged to secure air and sunlight ; and many forest trees lose their lower limbs (Fig. 487), or even die for lack of light. Plants growing in dark places, like potatoes sprouting in a cellar, are weak and tender, and their lack of color shows the absence of the important chlorophyl of the green cells. It is because of absence of sunlight that no plant life exists on the ocean bottom. Yet some low plants do grow in darkness. For example, a weirdlooking, pale white fungus lives in coal mines and caverns, where no ray of sunlight has ever entered. This is another instance of how life may adapt itself to very unfavorable surroundings. 212. Importance of Water. — No plant can live without water ; for it circulates among the tissues, bearing food and other materials from one portion to another, as man's blood does. In trees this plant blood is commonly called sap ; and when it rises in spring, the plant awakens from its long winter sleep and bursts into leaf and flower. Plants living in water have a supply ever at hand ; but most land plants obtain water from the soil, though in damp tropical forests some species secure enough from the air. If the soil dries, plants wither ; but in arid and desert regions plants have fitted themselves to survive long periods of drought. the neater, air, and soil. 213. Importance of Soil. — Soil is not necessary to plant life. Water plants, both fresh and salt, may secure all necessary substances from the surrounding water. Thus many float freely about, while others have roots solely for the purpose of anchoring themselves in place. Some land plants, called epiphytes^ are also able to live without roots, securing all necessary substances from the air. The great majority of land plants, however, depend on the soil for most of their water, part of their food, and for anchorage. The plant food in the soil is of so great importance that, where it is almost absent, as in sand, the soil is called sterile, and most species of plants do not flourish. Plants remove so much mineral matter from the soil that, where crops are raised year after year, it is necessary to use a fertilizer to replenish the plant food. Plants are adapted to different kinds of soils, some needing loose, open soil, others compact, clayey soil ; some requiring one kind of plant food, others another. A very little study of wild flowers or crops shows that plant life varies with the soil. Summary. — Most land plants depend on soil for ivater, mineral food, and anchorage; hut some land, and most water plants do not need soil. Land plants differ greatly according to the soil. 214. Importance of Gravity. — Plants send their roots into the ground, seeking water which gravity has drawn into the earth. Seeking sunlight, they send their stems straight up from the ground. This is the easiest way for them to resist the pull of gravity ; if they were inclined, for example, they would fall far more easily. To aid in withstanding the pull of gravity and the force of the wind, large plants build strong, woody trunks and branches. Water plants, on the other hand, are usuallyweak, loose-textured, and flabby, because they live in a denser medium, which buoys them up so that they do not need great strength to resist gravity. Such plants as sea weeds, which are exposed to waves, require a tougher texture. From what has been said, it is evident that the distribution of plants is influenced by surrounding conditions ; and since there i& much difference in the climate and soil of the earth, there are great differences in plant life. 215. Influence of Climate. — Climate is the greatest factor in determining the distribution of plants. Some species, especially the more lowly, have a wide distribution and are adapted to many climates ; but most plants of higher orders are fitted for only one set of surroundings. For example, sugar cane requires a warm, damp climate beyond the reach of frost; cotton grows best in a slightly cooler, though still warm, sunny climate; corn, though requiring a long, warm summer, grows much farther north than cotton , and wheat may be raised in a climate too cold for corn. Wild plants are limited in distribution in similar ways. There are, therefore, zones of plant life similar to the zones of temperature. An Arctic plant will die amid tropical heat as certainly as a tropical plant will perish when exposed to the frosts of a temperate winter. The plant life, or flora^ of moist climates also differs from that of arid climates. These differences may be best understood by studying the plant life in several climatic zones. Summary. — There are zones of plant life, similar to those of climate ; for, while some lowly plants are adapted to several zones, higher plants are usually fitted for life in only one. 216. Arctic Flora. — In the Arc tie, plants spring up as soon as the frost melts, and quickly flower and bear fruit, for the season is short. Lichens in great variety cling to the rocks (Fig. 486), and many mosses and water-loving plants live in the swampy soil. There are grasses, numerous flowering plants, and species with woody tissue, including dwarf willows and birches — true trees in all respects but size. They cling close to the ground, not rising high because it is important that the first snows shall cover and protect them from the cold blasts of winter. The short growing season, and the bitter winter cold, prohibit the growth of trees. For more than two thirds of the year, while the temperature is below the freezing point, plant life is dormant ; bai in the brief summer season the sap flows, the plants grow, pad the tundra is covered with a mat of green, dotted with bits of color. Yet only the surface soil is free from ice, for at depths greater than two or three feet frost is ever present. Summary. — In the short Arctic summer, ivhen frost melts from the iqjper layers of soil, ijlants grow rapidly, clinging close to the ground to secure protection from the winter cold. 217. Temperate Flora. — Near the margin of the temperate zone in both hemispheres is a timber line of low, scraggy trees struggling for existence amid unfavorable surroundings. The trees are all of hardy varieties, some evergreen^ others deciduous^ that is, shedding their leaves in autumn. The evergreens have tough, needle-like leaves which withstand the cold of winter, falling only in spring, when new ones take their place. Among the common evergreens are spruce, hemlock, balsam, fir, and pine. In the warmer part of the temperate zone deciduous trees increase in number and variety, including the beech, birch, maple, oak, elm, chestnut, hickory, ash, walnut, and many otlier species. There are also many fruit trees such as apple, pear, peach, and cherry. These trees, which spring into leaf and blossom in spring, and bear fruit in summer and fall, are checked by the autumn frosts. Their sap then ceases to flow, the leaves assume brilliant colors, then fall, and for a time the trees are dormant- They lay aside their activity during the season when active life is impossible. Other plants, called perennials, die down to the ground when the frosts come, growing again in spring from roots or bulbs in which nourishment has been stored during the active season. Still others, called annuals, die completely in the fall, leaving only seeds to reproduce their species when growth is again possible. The flora of the temperate zone varies greatly according to temperature, exposure, humidity, and soil. There are places where trees do not grow, for example on dry plains, and on prairies (p. 77), on which, however, grasses and many flowering plants grow luxuriantly. In other places tree growth is scrubby and of few kinds, as in sandy soils which support only pines and oaks. On the other hand, there are places where the climate and soil favor a luxuriant forest growth. Every part of the land is occupied to its fullest extent by plants fitted to live there. One of the most remarkable instances of plant growth is in the region of " big trees " on the west coast of United States (Fig. 488). There, a fertile soil, a damp, equable climate, and absence of strong winds encourage the growth of enormous trees. Only in southeastern Australia, where similar conditions exist, are there trees rivaling these in size. Some of the California trees are 300 feet high, 40 feet in diameter, and fully 2000 years old. Summary. — J^ear the frigid zone, tree growth ceases, the timber line being marked by scraggy trees, both evergreen and deciduous. Deciduous trees increase in number and variety in the ivarmer parts of the temperate zone. Plants are adapted to the winter season in several ways : by suspendiiig activity, by dying doivn to the ground, and by dying completely, leaving seeds to continue the species, TJiere are many differences hi flora according to temperature, exposure^ humidity, and soil. 218. Tropical Flora. In the warm, humid portions of the temperate zones, near the tropics, the abundant and varied flora is more like that of the tropical than of the cool temperate zone. It is therefore called subtropical. Both here and in the humid tropical zone the warmth and dampness favor the luxuriant growth of a great variety of species. Among these are long-leaved pines, broad-leaved evergreens, palmettoes, and palms (Figs. 493, 499) ; also such valuable trees as the teak, mahogany, rosev/ood, cocoa, banana (Fig. 490), and the rubber tree. There is no one season of growth, and no dormant period; blossoms may appear at any time^ and there is no period when all the leaves fall. The trees grow to great size, and, in their struggle for light, to great height. The undergrowth is dense (Fig. 494), trailing vines hang from the limbs, and epiphytes abound. Summary. — The suhtropical flora of the warm temperate zone and the tropical flora are quite alike in variety and luxuriance of growth, and in the absence of a dormarit period. 219. Flora of Savannas and Steppes (pp. 283, 285). — In regions where there is a season of drought, as in the savannas (Fig. 491) and steppes, trees cannot grow excepting along the streams. Many grasses and flowering plants bridge over the period of drought by means of roots, bulbs, and seeds, springing into life when the rains come, as plants of the cool temperate zone do at the close of winter. Therefore, such regions are excellent pasture lands. annuals and perennials thrive, making these good pasture lands. 220. Desert Flora. — In deserts there is too little moisture for a great number of individuals. Therefore, instead of having a complete cover of vegetation, the desert is scantily clothed with a scattered flora (Figs. 154, 498). Some plants have enormous roots, extending deep into the ground and spreading far about in search of water; tlie mesquite, for example, lias several times as much woody matter below ground as above it. Water is stored in these roots for use during the long droughts. Desert plants have many devices for existence amid their unfavorable surroundings. In order that the surface for evaporation may be reduced to a minimum, no more leaves are produced than are absolutely necessary; and in many cases the leaves are small and tough, or are even reduced to spines. In the cacti (Figs. 495497), which are especially well fitted for desert life, water is stored in the tissues ; there are no true leaves ; and the plant has a hard, shiny, varnished surface, through which evaporation is almost impossible. Some species are globular in form, thus exposing the least possible surface to evaporation ; and the sharpirritating spines protect them from many kinds of animals which might otherwise devour them. Many desert plants repel planteating animals, as the common sage brush does, w^liose tough, pale green leaves have a disagreeable odor and taste. Sunlight, temperature, and much of the desert soil are favorable to abundant plant life ; but water is lacking. It is remarkable that any plants should be able to adapt themselves to life where rain comes at intervals of months or even years. That this is the only unfavorable condition is proved where oases exist in the desert, or where irrigation is introduced. Then the watered desert supports plant life in great variety and luxuriance. Summary. — Because of lack of water, the desert flora is scattered and many devices are adopted to store enough ivater to last through the periods of drought. TJie luxuriance of growth on oases and irrigated sections proves that ivater is all that is lacking for plant life. 221. Mountain Flora. — In every zone the flora varies with altitude. A temperate flora is found on mountain slopes in the tropical zone; and an Arctic flora on mountain tops in temperate zones. Thus, species growing in Labrador and Greenland are also found on the top of Mt. Washington. by stunted, scrubby trees, is not regular, but extends highest on those slopes which furnish most protection from winds or longer exposure to the sun (Figs. 158, 161, 166). Above the timber line, wherever there is soil, the surface is covered with low bushes and flowering plants (Fig. 181), forming the mountain or Alpine flora, famed for the variety and beauty of its flowers. The cool summer air, damp soil, and long, cold winters resemble conditions in the Arctic ; but there is more sunlight. Mountains and high plateaus rising from desert lands may have rainfall enough for forest growth. On the lower slopes the trees are stunted, scrawny, and scattered, showing the struggle with drought; but higher up the forest becomes dense. If the mountains are high, tree growth may be checked above by cold, as well as below by drought. Summary. — Because of changes in temperature, the flora varies with altitude. On mountain slopes the forest disappears, and in the upper portion is replaced by the Alpine flora. 222. Water Plants. — Wherever conditions favor, both in salt (p. 195) and fresh water, there is a varied flora, some species floating on the surface, others anchored, and still others having true roots. Lower forms, such as algse and mosses, are especially adapted to life in water; but higher forms, even trees, are not absent. Rushes, reeds, mosses, and lilies are among the common fresh- water and swamp plants; and among trees the cypress, black gum, willow, and mangrove are common, the latter living in salt water (Fig. 379). Most trees die if their roots are submerged, because air is cut off; but water-loving trees have special provision for securing the necessary air. For example, mangrove roots start from above the water surface, and even from the lower limbs ; and knobs, or knees, grow upward from cypress roots till they project above the water surface (Fig. 307). 223. Means of Distribution. — Since the land is so well occupied that it is difficult for a new plant to gain a foothold, it is necessary that adequate provision be made to insure the spread of plants. Seeds are the principal means of insuring this spread. It is necessary to produce far more seeds than can possibly find a chance to grow, for some are eaten, some decay, some fall where they cannot sprout, and some that sprout find conditions so unfavorable that they die. In order that they may have every chance for a start in life, seeds are provided with many ingenious devices to aid in their spread. Some are so light that they are drifted about by the slightest breeze ; some, like the maple, have wing-like projections that catch the wind ; some, like dandelion seeds, have a light, feathery float; some, like the many burs, have hooks that catch upon the fur of animais ; and some, like the apple or peach, are covered with an edible coat. Animals eat these fruits, often depositing the hard, protected seeds far away from the parent plant. The wind and animals are the two agencies most important in spreading plants. Because light seeds are so easily carried by the wind, light-seeded plants are most widely distributed. Rivers also float seeds and plants from one place to another, and ocean currents may drift them even to oceanic islands. Man has become an important agent in distributing plants over the earth. He carries cultivated plants from one region to another, and also distributes many weeds. In this way the Canada thistle and the white field daisy, now common weeds, were brought to the United States. Summary. — Plants are distributed mainly hy seeds ; arid since many seeds are destroyed, far more are produced than coidd possibly grow. They are largely distrihided by ivind and by animals, with the aid of many interestiyig devices ; also by rivers, ocean currents, and by man. Light-seeded plants are most easily and widely distributed. In other words, water is a barrier to their spread ; it is, in fact, the greatest barrier to the distribution of land plants, especially if it is a large body like the ocean. It would be under very rare conditions, for example, that even a single seed could be carried from South America to Africa by winds, currents, or birds. Yet even the ocean is not an absolute barrier, and plants from the mainland are found on all oceanic islands. Only the seeds of certain plants find their way there, however, and island floras are, therefore, far less varied than those of the mainland. The most common plants are those with seeds so light that they are easily carried by wind ; or those that birds eat and carry; or those, like the cocoanut, that will float for a long time in the sea. Deserts are barriers because no plants, except those adapted to desert conditions, can spread across them, unless carried entirely over. A tropical forest is an equally good barrier for plants that are adapted to desert life. Mountain chains are also barriers, because plants at their base will not spread into the cold climates above ; but gaps or passes often are pathways for the spread of plants across mountains. The wind, although an aid to distribution in one direction, is a very important barrier to spread in the opposite direction. Tor this reason European plants are not likely to reach America against the west winds ; but these winds aid American plants in their spread to Europe. Ocean currents and birds also aid in the same direction. Summary. — The ocean is the greatest harrier to the spread of land x>lants ; hut even this is not an ah solute harrier, for plants ivhose seeds can be carried hy winds, hirds, and ocean currents are found even on reynote oceanic islayids. Deserts and Tnountains are also harriers ; and wind checks the spread of plants agaiiist it. 225. Variation in Plants. — Among plants there is a struggle for air, food, light, water, and opportunity to re produce their kind. This struggle is going on everywhere ; it may be seen in a neglected flower garden, where weeds spring up from chance seeds, and, being better fitted for the struggle than carefully nourished, cultivated plants, take complete possession of the garden. They tower above the cultivated plants, shutting out light and robbing the roots of water and mineral food. Under such conditions the cultivated flowers are small and imperfect. Because of this struggle for existence plants are steadily changing; and those that best fit themselves for the struggle have the best chance of surviving and spreading. This has been called the survival of the fittest. In this struggle plants have fitted themselves to survive the cold of winter; to live amid the unfavorable surroundings of the desert; in fact, to grow among most conditions on the earth's surface. Fossils in the rocks prove that similar change, or evolution^ has been in progress for ages. The following will serve as illustrations of how plants are forced to vary with environment, that is, to undergo evolution. A mountain, rising above the timber line and bearing an Alpine flora, is slowly worn down to the low, hilly condition of maturity. If the plants cannot adapt themselves to the changes in climate, slope, and soil, they must give place to forms better fitted. The effect of the ice sheet offers another illustration. As it advanced over the land, it either drove out or destroyed all life ; and near its margin the climate was changed from warm to cold, so that the plants living there either had to adapt themselves to the changes or die. When the glacier melted away a new soil was uncovered, and a struggle ensued for possession of it. The lightseeded plants came first, and even now the heavy-seeded plants are slowly advancing northward. These changing conditions have forced some species to evolve new characteristics. The history of plant life during past ages has been a succession of changes by which plants have become better adapted to their surroundings. Plants undergo many changes as a result of their relation to animals. Since animals depend on plants for food, some means must be provided to prevent complete destruction. For this purpose hard wood, thorns, bitter taste, and other means have been evolved. Many plants make use of animals, for example, in spreading seeds and in distributing pollen. Honey, odor, color, and many interesting forms of flowers are provided to attract insects and to secure from them the service of carrying the pollen. Man is now one of the most important agents in changing plants. By giving them better care, with plenty of light and food, and removing weeds, thus relieving them from the struggle with other plants, he is able to secure far larger seeds and fruits than grow naturally. For example, a good apple tree, left to itself, soon has to struggle with weeds and bushes, and its fruit becomes sour or bitter. By much care and many devices, men are constantly producing new varieties of flowers and fruit. This is done by forcing evolution to work more rapidly than it does naturally; and, in this way, changes may be caused in a few years which, by natural processes, might require centuries. Summary. — The struggle of plants to adapt themselves to their svrroundings, that is, the struggle for existence, which is everywhere and always in progress, causes iveaker forms to die out and results in the survival of the fittest. Slow changes in climate or in land form cause variation, or evolution, in plants. Changes are also brought about for the purpose of protection from, or making use of, animals ; and man is noiv causing changes at a far more rapid rate than evolution naturally icorks. 226. Plants of Value to Man. — Man, like other members of the animal kingdom, depends for food upon plants. Even though he may feed on meat, the animal from which it came receives nourishment, directly or indirectly, from plants. In a warm climate so great an abundance of plant food may be easily obtained, at all seasons, that there is little need of special provision. But in climates with a dry or cold season it is highly important to provide a store of food for use during the unfavorable season. This need has led to the cultivation of food plants. The portions of plants most useful for food are those in which nourishment has been stored to aid in the propagation of the species. Among these are seeds, like wheat ; fruits, like bananas ; bulbs, like onions ; and tubers, like potatoes. Some of the food plants, like dates, cocoanuts, bread fruit, and bananas, used extensively in warm climates, have been changed very little. portant of these, including the orange, apple, pear, peach, cherry, grape, wheat, barley, oats, and rye, have been carried to many parts of the world. In the case of many, the source is not now known ; but most of our food plants apparently came from Asia, where they have been cultivated for thousands of years. America has added the potato, tomato, pumpkin, and Indian corn, or maize, as well as tobacco. Plants also supply us with materials for shelter, clothing, medicine, and other purposes. Cotton (Fig. 503) is the most valuable of the several plant libers used for clothing. In all lands wood is used both for shelter and for ornamental purposes. Sugar (Fig. 501), coffee, tea (Fig. 502), cocoa, vanilla, tobacco, quinine, and many other plant substances, not of vital importance, are much used by men. The list of valuable plants is a very long one. For food and clothing, plants are carefully cultivated ; but for shelter it has been customary to depend upon the forest, which grows without care. In parts of Europe, however, so much of the forest has been removed that it has become necessary to cultivate even the forests, planting the trees, weeding out the poor ones, and carrying on lumbering with great care. The time has now arrived in America, when the forest needs to be cultivated. Accordingly, both the national and state governments have set aside large tracts as forest reservations. A division of the national government is known as the Bureau of Forestry, and a number of states have forestry bureaus. There are also schools of forestry, like those at Cornell, Yale, Wisconsin, and Michigan universities, where men are scientifically trained to be foresters. Summary. — Man and all animals rely for their food, either directly or indirectly, on the vegetable kingdom. In regions imth a cold or dry season, it is iiecessary to provide food for the unfavorable season, and this has led to the cultivation and improvement of a number of plants for their seeds, fruits, bulbs, and tubers. Many plants are also used to supply materials for clothing and shelter ; and now even forests are cared for by methods of scientific forestry. 217. Temperate Flora. — Timber line near Arctic ; evergreen trees ; kinds; deciduous trees; kinds; dormant condition in winter; perennial plants; annuals; treeless regions; sandy soils; "big trees." 225. Variation in Plants. — Cause of struggle ; illustration; struggle for existence ; survival of the fittest ; evolution ; illustrations of causes for evolution ; evolution in past ; securing protection from animals ; making use of animals ; effect of man on evolution. 226. Plants of Value to Man. — Dependence on plants; plant food in warm climates ; in places with an unfavorable season ; parts of plants used ; improvement ; important food plants ; source of food plants ; American food plants ; plants used for other purposes ; care of the forest. 216. State the peculiarities of plant life in the Arctic. 217. What are the conditions of tree growth near the frigid zone? In the warmer temperate zone? In what ways are plants adapted to winter conditions? How does the flora of the temperate zone vary? What conditions favor the " big trees"? 225. For what are plants struggling ? Give an illustration. What is the result of the struggle? What do fossils prove? Give two illustrations of how changes on the earth may influence evolution. What is the effect of the relation between plants and animals? How is man inflaencing evolution ? warm climates? In regions with cold or dry seasons? What parts of plants are used for food? What effect has cultivation had? Where have the cultivated plants come from ? For what other purposes are plants used ? What is now being done with the forest ? Suggestions. — (1) Place a hardy plant, such as moss, in boiling water for a few minutes, and plant it to see if it will grow again. (2) Freeze the same plant for a night and see if it will grow. Freeze a delicate plant, for example a geranium, and see if it will continue to grow. (8) Place a plant, say a geranium, in the cellar and let it grow for a few weeks, and note the change. (4) Leave a plant in its pot without water and see if it grows. Keep water up to the top of the earth (a swamp) and see if it kills the plant. Get a cactus and see if it will live in dry soil. Study the cactus. (5) Using the same kind of seed, try growing plants in several different kinds of soil, — sandy, fertile loam, etc., and see which thrives best. (6) Try to burn ash. Perhaps the teacher of chemistry can suggest an experiment to prove that there is mineral matter in ash. (7) Put a plant in a pot, inclining it at an angle to the surface. Will it keep on growing in that direction? (8) Collect and study seeds to see what devices they use for distribution. (9) Plant a bean in a flower pot in absolutely dry earth (a desert). Does it sprout? Place one in a jar of water. Does it grow after it has used up the nourishment in the seed? This illustrates why deserts and water are barriers. (10) Study the flora of your vicinity to see if the plants vary in kind from one soil, or exposure, to another. If there is a swamp, find how the swamp plants are different from those on dry slopes. (11) What crops are raised in your vicinity? What crops cannot be raised? Why? Is there a difference in crops according to the soil? (12) Make a list of plants valuable to man, their principal uses, and the localities from which they come. Let each student make a list, then combine it for the use of the whole class. Reference Books. — Coulter, Plant Relations, Appleton & Co., New York, 1899, $1.10 ; Merriam, Life Zones and Crop Zones of United States, Department of Agriculture, Biological Survey Division, Bull. 10, 1898, Washington, D.C. ; Bailey, Plant Breeding, Macmillan Co., New York, 1895, $1.00; Survival of the Unlike, Macmillan Co., New York, 1896, $2.00; Fernow, Economics of Forestry, Crowell & Co., New York, 1902, $1.50; GiFFORD, Practical Forestry, Appleton & Co., New York, 1902, $1.20. 227. Influence of Surroundings. — Plants and animals are alike in being dependent for life on their surroundings. Like plants, all animals, even those on the sea bottom, need air to breathe ; all require water for their blood and tissues : and for all it is necessary that the temperature shall be neither too high nor too low. Temperatures near the boiling point, or long continued below the freezing point, are fatal to animal tissues. Many, especially the lower animals, are able to survive a period of freezing ; others protect themselves by a coat of fur, feathers, or fat ; and some, such as bears, lie dormant in a protected place during the cold season. Most water and many land animals are cold-blooded; that is, Mieir temperature changes with their surroundings. They require so little air that many of them obtain ail they need from the water. Other animals, the birds and mammals, are warm-blooded, the warmth being due to slow combustion caused within their bodies by the oxygen they breathe (p. 229). Such animals require much oxj^gen and, even if they live in water, as the whales do, must rise to the air to obtain it. Those that live in water, or in cold climates, need to protect themselves by a warm covering in order to keep the warmth in their blood. Animals differ from plants in the way in which they secure food. While some remain fixed in one place, depending on supplies brought to them, as plants do, most animals seek their food. They need carbon and mineral substances, but are unable to secure them directly from air and earth. Even the food of flesh-eating animals may ])Q 2 A 353 tanco to animals. Unlike plants, animals do not absolutely require sunlight, since they do not need it to transform air, water, and mineral matter to food, as plants do. Consequently, animals are able to live even in the darkness of the deep sea. Like plants, animals are strikingly adapted to their surroundings ; if they were not, they would perish. Some spend most of their time in the air ; some live part or all of the time in water ; some dwell in trees ; some have homes on the land surface ; and some dwell at least part of the time underground. Flying, climbing, swimming, and running are developed to aid either in securing food or in escaping enemies. For these purposes there are many modifications in the shape of the body, — for example, wings for flying ; long arms, claws, and tails for climbing ; fins and boatshaped bodies for swimming ; long legs for running. Gravity influences the form and structure of the body. Since man stands upright, two legs only are required ; but four legs are necessary to sustain a body that extends parallel to the ground. Strong bones, or other structures, are needed to support the body on land ; but in water, which is denser, bones, where present, are much lighter. To maintain themselves in the air, flying birds have more feathers and lighter bones than running birds, and in most cases their bodies are smaller. Summary. — All animals must have air for breathing, water for blood and tissues, and a temperature neither too high nor too low. There are both ivann and cold blooded animals, and all are dependent on the plant kingdom for food. Animals are, in many ivays, adapted to their surroundings ; and there are many modifications fitting them to secure food and escape enemies. Gravity influences the form and structtwe of the body in many ways. Fig. 50t). — Polar bear and Arctic seal. The legs of the seal are changed to finlike appendages, used for swimming and for climbing upon the ice. Fig. 508. — Arctic whale. The legs have almost disappeared, and the tail is usi-u for swimming. In the mouth of this whale is a large amount of valuable 'vbalebone, on the edges of which are fringes which strain from the wat^\ 'iie small animalcule, upon which the whale lives. live in the ice-covered interior of (xreenland ; but in and near the Arctic Ocean there is much life, especially in summer. There are many kinds of fishes and other sea animals, and a great variety of sea birds feeding on them. When the freezing of the sea and land cuts off their food supply, most of the birds are forced to go southward ; wild geese, for instance. wJiich spend the summer on the tundras of northern America, fly as far south as Mexico. Other species go no farther south than Labrador and Newfoundland. During the summer, birds congregate in great numbers in their breeding places and, when frightened from their nests on the cliffs, rise into the air in clouds. On the land there are crows, ptarmigans, and some smaller birds; also hares, foxes, reindeer (called caribou in America), and musk ox (Fig. 505). There are practically no reptiles, for the great cold is unfavorable to such cold-blooded animals; but there are numerous insects, of which the mosquito is especially abundant. A number of mammals live part or all of the time in the sea. The polar bear spends most of his time on the sea ice, seeking the seal for food (Fig. 506). There are walruses (Fig. 507) and a number of species of seal, — warm-blooded, air-breathing mammals, which now and then leave the sea for a short time and take to the ice or shore. Whales also live in the Arctic (Fig. 508), but, though air-breathing, they never leave the water. The warm-blooded animals are well adapted to life in the severe Arctic climate. They are well protected, the birds with warm feathers and down, which keep out wind, water, and cold, the mammals with fur or fat, or both. In winter, when most needed, the fur is thickest. Eider down and the fur of the fur seal of Bering Sea are highly valued for their warmth and beauty. Many Arctic animals, like the fox, hare, and polar bear, are white like the snow and ice around them, thus escaping notice, both from their foes and their prey. The ptarmigan becomes white ill winter; but its summer plumage resembles the vegetation amid which it feeds. The baby seal, which spends its first days on the , ice, is also white; but as it grows older, and takes to the water, its color changes to more nearly resemble the water. Summary. — In the Arctic region there are many sea birds, which move southward in winter ivhen the freezing of sea and land cuts off their food supjt/y. On the land there are a few birds and mammals, numerous insects, but practically 710 reptiles. A number of mammals live part or all of the time in the sea. Warm-blooded Arctic animals are protected from the cold by far, feathers, and fat, and are often white like the surrounding snow and ice. 229. Temperate Fauna. — In the temperate zones animal life is more varied, and differs greatly from place to place. Certain species, like the bison (Fig. 518) and antelope, have become especially adapted to life on open plains; others, like the moose and squirrel, to the forest; others, like the mountain sheep and chamois, to high mountains; others, like the jack rabbit, coyote, and camel, to arid lands. Some, like the blindfish, live in caves, losing their eyes because they are not needed in the darkness. Still others, like the earthworm, Avoodchuck, prairie dog, and mole, burrow in the soil, spending part or all of their lives underground. Some, like the owl and wild cat, sleep by day and hunt by night ; but the majority rest when it is dark. An enumeration of all the animals of the temperate zones would be along list, for there is much variety among mammals, birds, reptiles, insects, and other groups. Among the birds are hawks, eagles, owls, hunmiing birds, thrushes, and a large number of singing birds; and along the coast there are many sea birds, including gulls, terns, ducks, and snipe. Among mammals are the bear, fox, wolf, deer, antelope, elk, moose, wild cat, squirrel, and hare, besides others mentioned above (Figs. 509, 510). One peculiar animal of the United States is the opossum, which belongs to the same division of the animal kingdom as the kangaroo. fur, highly prized by man. Fur-bearing animals of value, including mink, otter, sable, and beaver, are found especially in the cold north, where they are still hunted. The beaver (Fig. 509), a very interesting animal, cuts down trees and bushes with which to build dams to make ponds and swamps in which its plant food grows. His sharp teeth and flat tail are especially adapted to this work. Summary. — Animal life in the temperate zone is abundant and varied, different species being adapted to life on the prairies, in the forest, on mountains, in arid lands, in caves, and underground. Many mammals have far of value to man. 230. Tropical Fauna. — Since plants are the basis for animal food, animal life thrives where plants abound. Hence, animals are abundant in the tropical forest. Innumerable insects, fe.eding on pollen, honey, leaves, bark, wood, or decaying vegetation, some in trees and some on the ground, furnish food for countless birds. The insects include many beautiful butterflies ; also the interesting white ants, or termites, which build great structures of earth in which to dwell. The birds, including parrots, paroquets, humming birds, and birds of paradise, number thousands of species. There are also many reptiles, including turtles, alligators, lizards, and snakes. Among the snakes are venomous species, and huge boa constrictors, Avhich, hanging from the trees, resemble thick vines. One of the lizards, the iguana, attains a length of several feet. The mammals include the lion, tiger, hippopotamus, rhinoceros, giraffe, and elephant of the Old World (Figs. 511, 512), and the jaguar, puma, tapir, armadillo, and sloth of the New (Fig. 514). There are also monkeys, orang-outangs, gorillas, antelope, deer, zebras, and many other mammals. region. There is a great contrast between the abundance and variety of life in the African forest and its paucity in the Sahara desert. There is also a decided contrast between the abundant and varied life in an Arkansas forest and the limited fauna of the desert portion of southwestern United States. There the chief animals are the antelope, puma, coyote, jack rabbit, cotton-tail rabbit, rattlesnake (Fig. 510), horned toad, and a limited number of birds and insects. Animals need to be peculiarly adapted for life on a desert ; and their number and variety are limited by the small amount of water and plant food. Some, like the snakes, require little water, aside from what they secure from the animals they eat ; others are supplied with water from the roots or stems of the desert plants upon which they feed ; and still others live near springs, or go long distances to them. The camel (Fig. 512) is wonderfully adapted to desert life. It is able to make long journeys on the desert because of the store of water which it carries in its water pouch ; its broad, flat feet are admirably suited for travel over sandy surfaces ; and its nostrils may be closed to keep out sand which the wind blows about. Fresh-water Fauna. — Rivers and lakes have varied faunas, including especially fishes, insects, and lower invertebrates, or animals without a backbone. Among fishes many are of value for food, and some, such as salmon and shad, come from the sea into fresh water to lay their eggs. A number of birds and mammals, such as the duck, beaver, muskrat, mink, hippopotamus, and manatee or sea cow (Fig. 514), spend part or all of their time in fresh water, feeding on water plants and animals. Many insects and amphibia (toads, frogs, salamanders, etc.) breed in water, coming to dry land during a later stage. Numerous reptiles, including crocodiles, alligators, turtles, and some snakes, live in fresh water. There are many differences in fresh-water life. For example, the faunas of muddy water, sandy bottoms, swampy ponds, quiet water, and flowing rivers are quite different. Cold water supports less abundant and varied faunas than warm ; and salt lakes have very few animals. The Dead Sea receives its name because of the general absence of life, contrasting strikingly with the fauna of the neighboring fresh-water Sea of Galilee. When arms of the sea are inclosed and changed to fresh water, most of the marine animals die, though some species may survive •, also marine animals that enter fresh water may be prevented from returning to the sea. The landlocked salmon is a sea fish that has adapted itself to permanent life in fresh Avater. Summary. — Lower invertebrates, insects, fish, bii'ds, mammals, amphibia, and reptiles are adajjted to life in fresh water; and faunas vary with surrounding conditions. 233. Homes of Animals. — As a whole, invertebrate animals are peculiarly suited to life in water. Insects are the principal exception, though spiders, snails, and other invertebrates are also land dwellers. While most insects live on land, many live in fresh water, and a few in the sea ; and some, such as the mosquito, spend the early part of their life in the water. water, though some, like the turtle, live in the sea. While some birds, such as the penguin, ostrich, emu, and rhea, are unable to fly, most birds are especially fitted to live partly in the air and partly in trees or on the ground. Many, like the duck and penguin, spend much of their time in the water. Mammals are mainly land dwellers ; but the limbs of the bat have been changed for use in flight, and of the seal, walrus, sea cow, and others for use in swimming. Not a few, like the monkey, sloth, opossum, wild cat, and jaguar, spend most of their lives in trees. Summary. — Invertebrates are typically water dioellers, though some groups, especially most of the insects, live on the land. Reptiles and amphibia are land and water dwellers; birds, typical air dwellers, are also found in the water and on the ground; mammals^ typical land divellers, are also found in the air and water. 234. spread of Animals. — As in the case of plants, there is a tendency for animals to spread. To insure this, more young are born than can possibly live, some dying for lack of food, others being killed by enemies. It is during the young stage that animals are least able to protect themselves, and those animals, like fishes, which do not protect their young, must lay thousands of eggs in order that one of their offspring may reach maturity. It is a great step in advance when the young are protected and fed by the parents, as among birds and mammals, or among bees and some other insects. Then, since they receive protection during the critical stage of youth, fewer offspring are necessary. Those animals that take the best care of their offspring are the highest. The tendency to spread has taken animals to all parts of the earth; and evolution, or the tendency to change so as to become better adapted to surroundings, has caused them to vary. It is because of evolution that tlie European reindeer and American caribou, though of the same stock, are slightly different. The African elephant is a different species from that of Asia, though from the same original source; and the mammoth and mastodon, living in a cold climate, had a hairy coat, quite unlike the elephants of warm regions. Ocean dvyellers (p. 195) are among the most widespread of anintarl\|.; They swim, or are drifted, here and there; and their surroundings are so uniform that there is little reason for change. Because they can fly, insects, birds, and bats are among tlie most Avidely distributed of land animals. Those animals tliat walk or crawl move more slowly, meet more enemies, and find more barriers to overcome, such as rivers, mountains, deserts, and sea. For these reasons tlie large mammals and running birds are usually confined to limited areas. Yet some, especially the fierce carnivorous animals, cover a wide range; the tiger, for example, lives in the hot jungle, on open plains, and on cool movmtaiii slopes. Summary. — Many anwials make provision for the spread of thn species by the j^rodnctiou of numerous offspring ; but higher animals protect their young so that feiver offspring are necessary. Animals have migrated to all parts of the earth, fitting themselves by evolution to their surroundings. Ocean and fiying animcds are most tvidely distributed, ichile land dwellers move more slowly and are often coiv fined to very limited areas. 235. Barriers to the Spread of Animals. — The spread of animals is interfered with by the same barriers as in the case of plants. Water is the greatest barrier, but it is overcome by flying animals and by those small forms that may be drifted, clinging to logs. The tropical forest is a barrier to a desert animal, and the desert to one that needs water every day. Nor can animals accustomed to a warm climate or to life on plains, easily cross to the other side of a cold, rugged mountain range. Thus very different faunas may exist on opposite sides of such barriers, though some species, especially those that fly, will be the same on both sides. flying animcds. 236. Island Faunas. — The influence of the ocean as a barrier is well illustrated by the Bermuda Islands, which lie about 600 miles east of the Carolina coast, the. nearest land; They have never been connected with the continent, and yet the animals and plants are quite like those of the mainland. The flora includes the cedar and other northern plants, and cactus, palmetto, oleander, and other southern forms. The fauna consists principally of insects and birds, including ground doves, redbirds, bluebirds, and catbirds, like those on the mainland. A small West Indian lizard is also found ; and there are bats, the only native mammals. flew across ov were drifted by the wind. Every year birds from the mainland are seen in Bermuda, some resting during migration, others driven out to sea by winds. It is not at all uncommon, far from land, to see small birds resting on the spars and decks of vessels; and even the tiny humming bird has found its way as far as Bermuda. Doubtless the small land birds, driven out to sea during storms, find resting places on logs and clusters of floating seaweed ; but many must perish. Similar conditions exist in the A zores, off the European coast, and the Galapagos Islands, west of South America. The word Azores means hawk, and Galapagos, turtle, the names being given because these animals were common when the islands were discovered. Animals have crossed the ocean barrier to even the most remote islands, like the Hawaiian Islands in the mid-Pacifio. Summary. — The Bermuda^ and other islands, even the most remote, have plant and animal life from the mainland, shoicing that the ocean barrier can he crossed. Every year, birds stop on the Bermudas during migration, or because drifted oat to sea by storms. 237. Australian Fauna. — The fauna and flora of Australia are both peculiar. Among the birds are the emu and cassowary, two running birds ; also parrots, lyre birds, and other peculiar kinds. The mammals include several species of marsupials, the very peculiar monotremes^ and a few other species (Fig. 513). The monotremes, the lowest order of mammals, are represented by the remarkable duck-billed platypus (Fig. 513), which, unlike other mammals, lays eggs. The marsupials, another low order of mammals, to which the opossum belongs, include the kangaroo. These animals carry their young in a pouch, and, instead of walking, liop about by means of their long hind legs and stout tail. Alth(mgh higher forms of mammals inhabit southern Asia and the East Indies, they liave not found their way to Australia. were widespread. Australia was then so connected with other continents that these animals were able to migrate there. Fiercer animals have developed in the other continents and have killed off the monotremes and most of the marsupials ; but they have been prevented from reaching Australia because sinking of the land has cut off its connection with other continents. Therefore animals that belong to the geological yesterday are to-day living in Australia, though unfit to survive in other lands. They remain there only because the ocean protects them from the invasion of stronger species. Even dogs, introduced by man, and now running wild, are playing havoc among the defenseless marsupials. Summary. — The Australian fauna is peculiar, because the ocean barrier has prevented stronger species, developed on other continents, from entering and destroying the defenseless animals that came long ago, before these stronger species had been evolved, and when Australia was united loith other lands. 238. South American Fauna. — South American animals are also peculiar, though less so than those of Australia. The huge condor (Fig. 514), the largest of flying birds, lives there; also the rhea, a running bird, sometimes called the American ostrich; the llama and its allies ; various species of monkey; the sloth; the ant-eater; the armadillo; the tapir; and other strange forms (Fig. 514). The fact that these peculiar animals exist in South America, while only part of them extend up into southern North America, leads to the belief that South America has also been cut off from other lands, though not for so long a time, nor so continuously, as Australia. as in the case of Australia. 239. Faunas of Other Continents. — There is much closer resemblance between the life on other continents. In the north temperate zone there is such resemblance as to lead to the belief that there has been even better connection in the past than at present. For example, hairy elephants (mammoths and mastodons), now extinct, lived in Siberia, Europe, and North America; and among living animals, there are close resemblances throughout th^ (vhole region. The faunas of Africa and southern Asia are als^ quite alike (Figs. 511, 512), indicating close connection. Summary. — TJiere is close resemblance between the faimah of northern Asia, Europe, and America; also Africa and southern Asia, hidicating former land connection. 240. Zones of Animal Life. — The distribution of animals, ♦lescribed above, has led to the division of the earth into several zones, realms and regions (Fig. 515), each differing in important respects from the others. The differences between these zones are due to two principal facts: (1) that barriers — mountain, desert, and ocean — have cliecl^ed the spread of animals ; and (2) that evolution has developed animals of different kinds on opposite sides of a barrier. The boundaries of these zones are not sharply marked, nor are the zones absolutely unlike ; for some species will find their way across even the greatest barrier. among ayiimals that several zones of animal life are recogiiized. 241. Influence of Man. — Man has been a very important agent in causing changes among animals. In most parts of the world he has come in as an enemy, either seeking animals for his food or killing them because they destroy it. As a result, he has caused such a decrease among large wild animals that, in parts of America and Europe, very few remain. Some species, like the bison, have been almost exterminated (Fig. 518). Others have completely disappeared, for example, the mammoth and mastodon, with whose final extinction savac-e man doubtless had something to do. The dodo, a large running bird in the island of Mauritius, and the great auk (Fig. 505), once so common along the northeastern coast of America, have also been exterminated. The eggs of the auk were eaten in large numbers, and the bird itself, which was unable to fly, was easily captured. A single specimen of the auk or its egg would now bring a very high price, for most large museums have none. On the other hand, some species thrive under the influence of man. For example, rats and mice have been carried all over the world and have so greatly increased as to become a pest ; the English sparrow, introduced into America from Europe, has also become a nuisance ; and so has the rabbit, introduced into Australia. The rabbit destroys the food needed for domesticated animals, and the Australian governments have been obliged to take up the question of checking its further spread. Such domesticated animals as sheep, horses, and cattle, have had their range so extended that they are now found in all quarters of the earth. There is a limit to man's power in spreading animals. The camel and ostrich might be transplanted to southern California, but they cannot be made to thrive in New England ; the elephant or tiger could not be introduced successfully into the Arctic; nor the polar bear into the tropics. Yet, with care, man has been able to transplant some animals into all kinds of climates. Summary. — Man 7ias exterminated some species, especially the [ trger ayid more defenseless kinds, and has greatly reduced the mim\'ers of many others. Under his influence, other animals have had their range greatly' increased ; hut there is a limit to man's power of i\itroducing animals iyito climates for which they are not 7iaturally fitted, 242. Domestic Animals. — Man has been very successful in adapting animals to his needs; and, by so doing, he has greatly increased his own prosperity. To have a horse or buffalo to help in his work, or sheep or hens for food, adds greatly to a man's resources. He can do more work and mak^i more progress; and the most advanced races are those 'v:th the greatest number and variety of domestic animals. Some animals resist efforts at domestication; it seems scarcely possible, for example, to domesticate the lion. Yet it is remarkable how large a number of animals man uses The reindeer of northern Europe (Fig. 546) is used as a draft animal and for food supply. Eskimo dogs (Fig. 525), which are little better than half-tamed wolves, are of great service in-hunting and in drawing sledges over the ice. In the highlands of central Asia the yak is domesticated; the buffalo (Fig. 520) and elephant (Figs. 512, 521) in southern Asia, and the camel (Fig. 519) in the arid belts of Africa and Asia. Cats, dogs, horses, cattle, sheep, goats, and pigs are domesticated all over the world. Among domesticated birds are hens, turkeys, ducks, geese, and doves. As in the case of plants, the origin of many of these is not known ; they date back thousands of years, long before the first records of history. It is a striking fact that the ]Se\v World has supplied only two domesticated animals, the llama of South America (Fig. 514) and the turkey. If it had not been almost exterminated, the bison probably could have been domesticated. On several ranches in the West there are now small herds of bison from which it is yet possible that this animal may be domesticated. Summary. — WJdle some animals resist domestication, man has succeeded in adapting many mammals and birds to his use, either for food or as work animals. Of these, the New World has supplied only two, the llama and turkey, though the bison may yet be added. Topical Outline. — 227. Influence of Surroundings. — Air ; water* heat ; cold ; cold-blooded animals ; warm-blooded animals ; cause of warmth. ; protection ; dependence on plants ; sunlight ; mode of life , means of securing food and escaping enemies; influence of gravity. 228- Animal Life, or Fauna, of the Arctic. — Animals in and near the sea; sea birds; southward migration; land birds; mammals; reptiles ; insects ; mammals in the sea ; protection from cold ; white color. ..'?9, Temperate Fauna. — (a) Mode of life: open plains; forest; moui. ^ins ; arid regions; caverns; underground; nocturnal animals. (b) Common animals : variety ; birds ; mammals ; opossum ; fur-bearing animals; beaver. 236. Island Faunas. — (a) Bermudas: position; plants; animals. (h) Means of reaching islands: currents; flight; wind; birds at sea. (c) Other islands : Azores; Galapagos; Hawaiian Islands. 237. Australian Fauna. — (a) The animals: birds; monotremes; marsupials, (b) Explanation : former distribution ; development of fierce enemies; separation of Australia; protection by ocean barrier. 241. Influence of Man. — (a) Man as an enemy : cause for destruction ; general result ; bison; mammoth and mastodon; dodo; auk. {Ji) Influence in spreading animals : rats and mice ; English sparrow ; rabbit ; domestic animals, {c) Limit to influence ; examples. Review Questions. — 227. What is the dependence of animals on air, water, and temperature? By what means is cold endured? What is the difference in the blood of animals? Why are animals dependent on plants for food ? Why are they not dependent on sunlight? In what positions do animals live? How are they fitted to secure food and escape enemies? State the influence of gravity on the body. 228. AVhat is the nature of Arctic bird life ? What is the condition of life on land ? What warm-blooded animals live in the sea? How are Arctic animals protected from the cold? What about their color? 231. Contrast desert and tropical forest faunas. What animals are found in the desert of southwestern United States? Why are there so few ? How do they secure water? How is the camel adapted to desert life ? 234. In what way is the spread of animals made certain? Give illustrations of evolution. What kinds of animals are most widespread? Why ? What about land animals'^ 241. Why is man an enemy of many animals ? Give illustrations of his influence in extermination. In increasing the range of animals. How is his power limited in this respect? 242. Of what advantage are domestic animals? Give instances of domestic animals in various parts of the world. What domestic animals has the New World supplied? What about the bison ? Suggestions. — No special suggestions are made for this chapter, largely because of the difficulty of offering suggestions adapted to large numbers of schools. Yet a teacher especially interested in this phase of the subject will find opportunity for illustrative work, — with books, pictures, specimens, and museums, if in a city ; in the field, if in the country. Reference Books. — Wallace, Island Life, Macmillan Co., New York, 1892, 81.75 ; Geographic Distribution of Animals, Harper Bros., New York, 1876, -flO.OO; Heilprin, Dlstrlhution of Animals, Appleton & Co., New York, 1886, $2.00; Beddard, Zoogeographij, Macmillan Co., New York, 1895, $1.50; Lydekker, Geographical History of Mammals, Macmillan Co., New York, 1896, $2.60; Le Conte, Evolution, Appleton & Co., New York, 1891, $1..50 ; Jordan, Factors in Organic Evolution, Ginn Sc Co., Boston, 1894, $1.25. DEVELOPMENT OF MANKIND. 243. Early Man. — What sort of life people lived before they Avere sufficiently enlightened to leave any written records, we can judge only by the records of their deeds as shown in mounds, monuments, drawings, utensils, weapons, and other relics, and by comparison with other uncivilized people of the present day. Written records tell us much about our ancestry during the last two or three thousand years. For example, when the Roman Empire was developing, the Germans and English were rude savages; and still earlier, the inhabitants of the Italian Peninsula were in the same condition. To-day, both in the Old and the New World, there are races that have not yet risen above savagery. The study of human development through labor and thought is most interesting, even though there are many gaps that can be filled only by the use of reason and imagination. Ever since man has been compelled to earn his bread by the sweat of his brow, the brightest men have sought to conquer nature and modify their environment by the use of their wits. Steadily through the centuries mon has acquired useful knowledge from experience ; and, as a result of his efforts, modern civilization enjoys many advantages, comforts, and conveniences over savage and semicivilized people. 244. Dependence of Man on Nature. — Even the most civilized men are dependent on nature, as animals and plants are. Man must have air to breathe, water to drink, and food to eat. Furthermore, his sight depends on sunlight, and his speech and hearing on sound waves, transmitted through the In these respects both savages and civilized men are dependent on nature ; but to live as civilized men do, we must rely on other things as well. For warmth and light we depend on coal and oil ; for manufacturing, upon coal and water power; for transportation, upon coal and wind; for communication, upon electricity; for many objects of daily use, upon mineral substances. The resources of the world are drawn upon by civilized nian, and his powers have so developed that he has learned to adapt to his needs many of the products and forces of nature. Each year his ability to do this increases. In this respect man has risen immeasurably above all other forms of life. Summary. — All men depend on nature for car, icater, and food ; and civilized man is dependent for many other things. Each year he is learning better how to make use of nature. 245. Food Supply. — Man began his conquest of nature because of the need of food. The steam engine, the factory, and wireless telegraphy are the climax of a series of inventions which began when, to the teeth and claws with which animals secure food, man added simple implements. By using stone implements, such as spear and arrow points, hammers, and hatchets ; by fashioning wood for handles and for bows; and by making simple hooks for fishing, early man greatly increased his ability to obtain animal food. Even to this day, savage races make use of such primitive implements (Fig. 522). As an important source of food, primitive man made use of plants, especiall}^ the seeds, fruits, bulbs, and roots. The mandioca, sweet potato, potato, yam, plantain, banana, cocoanut, date, and the grains, including wheat, barley, rye, corn, rice, and millet, are among the leading plant foods. To gather these, scattered as they are in nature, required much work, and early man naturally found it profitable to plant of stone or wood, aided greatly in this work. By domesticating plants (p. 348) and animals (p. 365) a great addition was made to man's resources. Domestication is the basis of civilization, for it gave man the habit of working, of storing up for a season of need, and of trading ; upon it also depends the idea of property and of the home. To-day all the world depends for food on the farmer and herder. Wherever conditions favor, the land is cleared for farming, and the majority of mankind are engaged in the production of food for themselves or for those with a different occupation. The plow, the reaper, and the threshing machine have taken the place of the primitive spade and hoe. Thousands of railway cars and vessels are constantly engaged in moving products of the faiirs to places where men are engaged in other pursuits, or where the population is too dense to permit the production of all the food needed. Agriculture is by far the most important of industries. Summary. — Tlie devising of simjyle ifniplemeyits for securing i^Uutt and aniynal food is the basis of modem invention. Tlie domestication of pUuds and animals for food is the basis of our civilization. All the v'orld depends for food on the farmer and herder, and agriculture has become the most important of industries. 246. Clothing. — In a hot climate man has little need for clothing (Fig. 522) ; but in a cool or cold climate some protection is necessary. Without it man could not occupy the cold temperate zane. Various natural products, including skins (Fig. 523), wool, and plant fibers, have been used to protect the body. Early Germans and Britons were clothed in skins, as the Eskimos are to-day (Figs. 524, 525). In cold climates one of the objects of hunting has always been to secure materials for clothing ; and one of the objects of herding is the production of wool and leather, and of farming, the production of fibers for cloth. The principal vegetable fibers used for making cloth, rope, etc., are cotton, flax, hemp? and jute. widely used by civilized people for clothing. The production and manufacture of materials for clothing now .»ank among the great industries of the world. The fact that the most civilized races live in the cool temperate zones makes the production of materials for clothing far more important than if their homes were in the tropical zone. Summary. — Clothing is needed by all dwellers in cool climates, and for it, various animal and plant j^roducts are used. Since the most civilized races live in the cool temperate zones, the production and manufacture of clothing are among the most impjortant of industries. houses are still built in many regions. Grass huts, and branches woven into a simple shelter (Fig. 529), are common in the tropical zone; and some savages live there with hardly any shelter. In parts of Europe and southwestern America, caves and overlianging ledges furnished shelter to primitive man. Fig. .527. — Thatched house in the Philippine Islands, needed for protection from sun and rain, not cold. It is raised above the ground to avoid dampness and to prevent the entrance of animal pests, which are very troublesome. nent homes. The use of wood began in forest regions (Fig. 528), at first doubtless by the use of boughs, branches, and logs ; then of rough-hewn boards. Simple log cabins, some of which still remain, were built by pioneers in America. ployed in arid countries, as the Holy Land, Spain, and New Mexico. These are too easily affected by dampness for use in moist climates ; but the discovery of how to bake bricks by fire has made the use of clay possible there. In arid regions, where trees are scarce or absent, stone and sundried bricks are very widely used. a series of improvements, from these simple beginnings. The cold of winter calls for further protection than that furnished by clothing and houses. Fire supplies this, and it is safe to class the use of fire among the greatest of human discoveries. It has become of value not merely for heating, lighting, and cooking, but as the basis for much of our modern manufacturing. It has led to mining of coal, production of oil and gas, mining and manufacturing of iron, and many other industries. As a re^^ult of articles about which primitive man knew nothing. Summary. — Menu/ primitive means have been employed for securing shelter ; for example, skins, snow, blankets, grass, branches, and caves. Tlie use of wood, stone, and clay doubtless started in a very primitive way : wood from the use of boughs and logs; stone from mere piles ; aud clay in the form of sun-dried brick. The discovery of fire has been of great importance, making 2)ossible manufacturing and thus opening to man^s use many otherwise itseless matericds. Guinea. There are many illustrations of the location of houses on sites that give protection from enemies. Some savages build houses in trees (Fig. 530), and some on piles in water (Fig. 534), as the ancient lake dwellers of Switzerland did. The Pueblo Indians safe from attack Fia. 533.— Housjs built ou a steep hillside in a inoimtaiuous peninsula soi^^tli of Naples, Italy. A few spots on the slope are cultivated, but most of the laud is unfit for cultivatior Thf. bouse,, art, however, uea,i tLt, wat« and fisJiing' is poH«i>»i 249. Location and Growth of Cities. — When scattered it is easier for men to secure sufficient food than when many live in a single place ; but it is less easy to ward off the attacks of enemies. Largely for this reason, the custom has grown for men, even savages (Figs. 529, 530, 534), to gather into communities. From their villages, these primitive people go out to the neighboring fields, forests, and waters for farming, hunting, or fishing, and yet, being near togetlier, are ready to resist attack. They are also ready for an expedition to attack a neighbor for revenge or profit. The leader in attack or defense easily became chief of the nllage ; if powerful enough, he might become ruler of several villages. Even at present nations grow in power and territory by conquering weaker peoples. Government has become very complex, and differs greatly among nations ; but, like all our wonderful modern life, it had its beginnings in the simple practices of our early, uncivilized ancestors. Many European towns grew np because of the need of defense. One man, more powerful tlian tlie rest, built a strong stone castle, perhaps on a hill, and protected the region about it by a wall. Farmers, soldiers, and others, under the protection of tlie castle owner, worked for him, lived in houses within the walls, and helped defend them when attacked. In Europe, hundreds of places like this are still to be seen, although no longer used for defense. Around some, with favorable situations, large cities have developed. In locating cities, at present, there is no need of considerinsr defense. The ^reat cities of the civilized world are the capitals of large nations, and the busy manufacturing and commercial centers. London, Paris, Berlin, Vienna, Brussels, St. Petersburg, Madrid, Rome, Constantinople, and other large Euro[)ean cities are capitals. The first five are also manufacturing centers ; and London, Paris, St. Petersburg, and Constantinople are able to carry on commerce by sea. Each of these cities has a location favorable to growth. All flourishing cities in the world, whether great or small, owe their prosperity, in large part, to their favorable situation. Some, like Milan in Italy, and Vienna in Austria, are situated where routes of travel converge or cross. They had their beginning long before the days of railways ; but the railway, making them centers of modern traffic, has greatly increased their prosperity. Many cities, like Cincinnati, St. Louis, Vienna, and Paris, are on rivers ; and others, like Buffalo and Chicago, are on large lakes. Still others, like Genoa, Liverj)ool, San Francisco, and New York, are seaports. Such seaports as London, New York, Philadelphia, Baltimore, and New Orleans, which are at the mouths of rivers that open pathways into the interior, have exceptionally favorable situations. Many cities, like Lowell, Lawrence, and Rochester, owe thei\ growth to water power, which has enc^ouraged manufacturing. Others, like Scran ton, Wilkes Barre, Pittsburg, and Denver, owe their development mainly to near-by mines. Can you mention other instances of cities whose growth depends on their favorable location ? What has helped determine the growth of your own city ? Summary. — Tlie tendency of peoj^le to congregate in centers had its origin in the need of defense, and from it has arisen government. Some large European toums grew around fortified castles ; hut the largest have prospered either because they are capitcds of great nations or are manufacturing and commercial centers. Flourishing modf^rn cities are mainly located on one of the following sites : at the crossing of trade routes ; 07i rivers, especially at their mouths ; on harbors; on lake shores ; near water poicer ; near mines. 250. Development of Commerce. — Even primitive men desire articles which they cannot produce. For example, remote Eskimo tribes will gladly exchange skins for pieces of wood ; and central African negroes will trade ivory for simple trinkets. Two ways of obtaining desired objects are open : one to seize them, the other to give articles in exchange for them ; and both methods are resorted to. From exchange, commerce has developed. Objects of trade were early carried overland, at first on foot, later by the aid of animals, even across deserts and mountains. The first commerce by sea was carried on in small, open boats, propelled by oars; later, sails were used. Even before Bible times, and before Europeans became civilized, caravans crossed the deserts of Asia Minor, bringing treasures from Asia. The inclosed Mediterranean offered opportunity for the extension of this commerce by sea ai:d for the introduction of Asiatic civilization along its shores. A powerful nation developed on the Grecian peninsula, and its irregular coast bred a race of sailors. Even to-day the Greeks are the sailors of the Mediterranean. The ancient Greeks carried their commerce to all parts of the Mediterranean, establishing colonies which later developed into powerful independent nations. As the boats were made larger, the commerce which developed among Mediterranean nations was gradually extended into the open ocean, and even up the Euroj^ean coast to the British Isles. The Mediterranean may be called the cradle of early navigation. carry the increasing commerce of the world over all oceans. Commerce was once carried on by actual exchange of goods, and in some cases this is still done. But a far better way is to have some medium of exchange. Such a medium is money. The use of money is far simpler than direct exchange. For example, a man who needs shoes might hnd it difficult to get them if he had only his labor to offer; but if he receives money for his labor, he can get what he needs. Any substance that has a recognized and fairly nniform value could be used as money. Gold is generally used, because it is not too common, is not easily destroyed, and is valued by all peoples for ornament. has brought people into closer communication and sympathy with Fig. 535. — The Suez Canal. The neck of land which separates the Mediterranean and Red seas forced those who sought a water route to India, four or five centuries ago, to undertake the explorations which led to such important discovei'ies. The demands of modern commerce for a shorter water route between Europe and Asia led to the construction of the Suez Canal. MAN anb nature. 379 one another, and has made peo'ple in one section learn from those in another. As a means of commnnication, writing has developed, and, like other features of our civilization, this has been evolved from simple beginnings. For example, picture writing, or recording events by symbols carved on wood or stone, has been used by many primitive peoples (Fig. 538). From this the alphabet developed, then printing, which has proved so important an aid in spreading knowledge. The telegraph, ocean cable, and telephone, made possible by the use of electricity, have now brought all parts of the civilized world in close touch with one another. Wireless telegraphy is the last great advance in commanication. It is part of the progress of the human race toward higher and higher civilization, in which commerce has had so great an influence. Summary. — Commerce has developed from simple exchange carried on among primitive peop)le, at first overland, either on foot or by the aid of animals, and on the sea by the use of boats propelled by oars. Early commerce betiueen Asia and Europe, overland across Asia Minor, and thence in the inclosed icaters of the Mediterranean, made the Mediterranean the cradle of navigation. The discovery of a luater route to Asia, and of the Neia World, resulting from the closing of routes to Asia by the Mohammedans, have led. to the development of larger ships and to the great advances of modern commerce. The use of money, the extension of civilization, the development of loriting and printing, and communication by electricity are among the important outcomes of the development of commerce. 251. Influence of Man on Nature. — In his progress, man has in many ways profoundly influenced his surroundings. He has modified, extended, and destroyed plants (pp. 348, 349) and animals (pp. 364, 365). By removing the forest he has made it possible for water to run off more rapidly (p. 50), washing soil into the streams and causing great variations in river volume. A.s a result, some streams formerly useful for water power are now too variable ; and some areas, as parts of Italy, France, and Mississippi, have had their soil stripped off, leaving either bare rock or a surface too badly gullied for farming (p. 51). have been straiglitened and deepened for navigation, and canals dug around rapids, and from ocean to ocean. For use in irrigation, river water has been led over arid lands ; and lakes and ponds have been formed to secure steady water supply for irrigation and for other purposes. Each of these acts of man interferes with natural conditions. Along the seacoast, walls are built to check the work of the waves. To better lit them for shipping, harbors and channels are dredged; jetties and sea walls are built to prevent currents from closing harbor mouths with sand bars ; and, by building breakwaters, harbors are actually made by artificial means. Much change is made on the dry land also. The ground is pierced with wells for water, oil (Fig. 542), and gas, and these substances are led to the surface. In the removal of coal, iron, and other mineral products, the strata are honeycombed with shafts and tunnels (Fig. 541) ; and in quarrying, and in removing clay and sand, hills are lowered and deep pits made. Tunnels are dug through mountains (Fig. 186) and deep cuts made in hillsides, while great embankments are built of the rock removed. Earth and rock are removed in making roads and in digging cellars ; and, over great areas, the soil, by being loosened and overturned in plowing, is exposed to the weather. These are some of the ways in which man is at work overcoming obstacles which nature has placed in the way of his advance. Civilized man brooks no obstacle ; he removes it where necessary ; he is everywhere at work modifying nature to serve his needs ; and he is utilizing his surroundings, and the forces of nature, to help in his onward march toward higher civilization. In this respect man stands apart from all other forms of life. Summary. - //v <i niuUittule of 2vat/s man is influencing nature: (leatrot/itif/, niod/fi/iiK/, or extending the range of animals and plants ; removing the fon^st, thns allowing the rain to run off' rapidly and carry aicay the soil ; changing or conlrolling streams; improrlng or making ivaterivays ; forming lakes ; interfering with the natural action, of oceanic agencies ; boring into the earth and removing materials; and exposing soil and rock to the iveather. In fact, he is overcoming ull obstacles and makiiig nature serve his needs. Ftg. 541. — A coal mine at Shenandoah City, Pa. Here the ground is honeycombed with shafts and tunnels, and vast quantities of coal are removed, together with associated rock, great piles of which are seen near the buildings. 252. The Spread of Man. — During the development of man, as outlined above, he has migrated to almost all lands. Starting from some common center, he spread slowly, guided by the same laws as animals, and influenced by the same barriers. But man's superior intelligence has permitted him to spread farther than any species of animal, and to adapt himself to all climates. Even as a savage he reached every continent and most oceanic islands. The use of boats aided him in crossing the ocean barrier; and, by means of clothing and shelter, he has overcome the barriers of cold climates. The spread of man has been in part a slow, steady advance outward in all directions, as in the case of animals, and in part a rapid migration in large numbers. It was such rapid spread that led to the building of the great Chinese wall (Fig. 543) as a barrier to the hordes that moved outward from central Asia. Similar hordes from Asia overran Europeand still others crossed the Alps and advanced to Rome The spread of man has often been a part of warfare and conquest. This is illustrated by the Roman Empire which, bj conquest, caused the diffusion of Romans and Roman civilization, not only along the Mediterranean shores, but throughout western Europe, even as far as the British Isles. The discovery of new lands, especially in the New World, has had a great influence on the spread of man. By the time of Columbus there had been such advance in knowledge of sailing, including the coming into use of the compass, that even the ocean could be crossed at will. The much higher civilization of Europeans enabled them to displace the savage occupants, not only of America, but of Australia and the more attractive parts of Africa. Commerce is at present aiding in the general spread of man. inteUigeiice, and especially the use of boats, clothing, and shelter, has made it possible for him to spread much farther. Man's spread has been in part slow migration, in part rapid movement in large numbers, often as a part of ivarfare and conquest. The discovery ofneio lands, occupied by savages whom he could displace, has greatly helped m man^s spread ; and commerce is now aiding it further. 253. Races of Mankind. — Although there are decided differences among men, all are believed to have come from the same stock. Through the influence of climate, and other surrounding conditions, they have become varied in color, form, and habits. On account of these differences it is customary to divide mankind into several classes, or races. There is (1) the black, or negro (^Ethiopiari) race ; (2) the yellow (^Mongolian') race; (3) the red, or Indian (^Americany race; and (^4: ) the white (^Caucasian) race. A fifth division, the brown (^Malay) race (Fig. 545), is often recognized. Because there has been a mixture of blood wherever they have come in contact, the boundaries between these races are not distinct (Fig. 544). Moreover, the members of one race have often migrated into the territory of another. Thus the Finns and Hungarians, though surrounded by Caucasians, are Mongolian in origin. The red men were originally confined to the American continent, and have never migrated to other regions. But other races have spread widely. In modern times the Mongolians have spread very little, and the negroes have spread mainly through the influence of white men, who have carried them as slaves, especially to the \ew World. The white race, on the other hand, has migrated .extensively, taking the place of weaker and less well-fitted people. This is well illustrated in America, where the Indians have been slowly driven back by the aggressive, civilized Caucasians. Summary. — Mankiiid is divided into four main races: (1) the black, or Ethio/nau; (2) the yelloiv, or 3fongolian; (3) the red, or American; and (4) the 'white, or Caucasian. Because of intermi.V' tare and migration, the boundaries betweeji these races are by no means distinct. 'The white race is now rapidly extending its range and influence, and is taking 2>'^'^s'e.s'i'/o?i of the earth. Fig. 545. — Races oi' iiuiiikiiid. Ked, or Jiidiaii, upper left; black, or Etliiopiaii, upper right; white, or Caucasiau, middle; yellow, or Mongoliau, lower right; brown, or Malay (a branch of the yellow race), lower left- INFLUENCE OF SURROUNDINGS. 254. Man in the Arctic. — Agriculture is impossible in the Arctic, and tiiere is too little ])lant food to support liumau life (Fig. 486). Under such unfavorable conditions, the inhabitants of the North must look to animals for food ; and, been introduced into Alaska. Life in the Arctic is well illustrated by the Eskimos (Figs. 524, 525), who live along the coast, depending for food chiefly on birds, seal, walrus, and bear. The extent to which these interesting people depend on animals is shown by the following : they obtain from them most of their food ; skins for their clothing and summer tents, or tuples; bone for their spears; and bone framework and skins for their boats, or kayaks. Wood, occasionally drifted to their shores, is one of their most highly prized possessions. To live amid such surroimdings reqnires great hardiness and constant effort; and death by starvation is not uncommon. The Eskimo has to work hard in order to obtain the barest necessities, and there are no luxuries. How difficult his life must be is indicated by the disasters which have befallen many Arctic explorers. Such surroundings oifer little opportunity for advance. Summary. — The Arctic is sparsely populated, mainly along the coast Inhere there is most animal food; hut in the Old World the reindeer is domesticated, increasing man's chance of living. The Eskimo depends on animals for food and materials for shelter, clothing, and boats. Life in the Arctic is so hard that there is little chance for advance, all the energies being needed for obtaining the barest necessities, 255. Man in the Tropical Zone. — Conditions in the tropical zone are quite opposite to those in the Arctic. There man is surrounded by an abundance of food, both plant and animal, and he requires little clothing (Fig. 522) or shelter (Figs. 527, 529, 530). All his needs are met with slight effort, und there is little cause for work. Moreover, the climate, especially if damp, is unfavorable to work. Under such conditions man resembles animals in being content with bare necessities. Being so easily satisfied, he cannot advance far in civilization. It is for these reasons that some of the most uncivilized peoples of the world to-day are found in hot climates. The Indians of Central and South America, the negroes of central Africa, tlie Australian natives, and the Negritos of the Philippines are examples. Among many of these people, as among animals, the eating of one another, or cannibalism, is still practiced. Yet they talk, they think a little, and they know the use of simple implements. When brought under the influence of civilization they advance, showing that it is only surrounding conditions that have kept them so low. Summary. — In the tropical zone the ease of obtaining food, and the small amount of clothing and shelter necessary, call for little ivorTc, to which the hot, damp climate is unfavorable. It is for these reasons that the least civilized races are found in the tropical zone. 256. Man in the Temperate Zone. — This zone has been the birthplace of civilization, mainly for the following reasons : (1) while there is an abundance of food in summer, there is little in winter. It has, therefore, been necessary to secure food in summer and store it for winter use. This requires energy, intelligence, and foresight ; yet the amount of work necessary is not great enough to discourage or to prevent advance. (2) Both clothing and shelter are needed, and to provide these also requires intelligence, ingenuity, and energy. (3) The lands of the temperate zone are irregular, and the climate vai led. This has led to the growth of different crops\ in different sections ; and the people of one section, desiring the products of another, have opened communication with them. From this has arisen commerce, leading people of one region to learn from those of anotlier. To meet the needs of winter, the people of the temperate zone have developed the habit of cultivating crops, and have devised means of making work easier. They have domesticated animals for food and as aids in their work ; they have made implements ; have learned how to use metals ; have developed the art of building; have discovered the use of fire; in fact, in supplying their needs they have learned to call all nature to their aid. The civilization that developed in the north temperate zone has now spread to all zones. Summary. — T7ie need of providing food, clothing, and shelter for ivinter has caused x^^ople of the temperate zone to advance; and the varied products of different sections have given rise to commerce. In this advance the cidtication of crops, the lomestication of animals, the art of building, and the use of metcds md fire have been learned. Thus modern cicilization has arisen. 257. Man in the Desert. — Living on a desert resembles life in the Arctic in the fact that there is so little food that laien often die of starvation. But the nomads of the desert (p. 89) have domestic animals, — cattle, horses, and camels especially, — which hel[) them greatly. Their mode of life makes these wanderers intelligent and brave, otherwise they could not live amid such surroundings; but they do not hesitate to seize from others the goods they need Desert conditions are so unfavorable that people more civilized have not entered to crowd the nomads out ; and the desert barrier prevents the inhabitants from learning of others. For this reason, customs of the time of Christ are to-day preserved among the inhabitants of the Old World deserts. On oases conditions are very different, for there agriculture is possible. Large oases, such as the valleys of the Euphrates and Nile, have been cradles of ancient civilization. Civilization early developed in such situations because it was necessary to work in order to store up food for the season when crops will not grow; and the surrounding desert served to protect the stores of food from invaders. Both in the Euphrates and Nile valleys, and in other oases of the Old World, there developed a wonderful ancient civilization, which spread along the shores of the Mediterranean. This ancient culture is the foundation of our modern civilization. The oases were favorable to the beginning, and the Mediterranean to the spread of civilization (p. 377) ; but the desert barrier has interfered with the introduction of the modern civilization which has developed in other parts of the temperate zone. Consequently, these cradles of ancient civilization are now far behind the world. The most advanced of the American Indians were those that lived in similar situations. The Pueblo Indians of New Mexico, the Aztecs of Mexico, and the Incas of South America lived in positions where agriculture was possible, and where deserts or mountains offered partial protection from invasion. When discovered, these red men were barbarians, far higher than the other Indians, who were savages. Summary. — Because of lack of food and icater, desert conditions are unfavorable, and the inhabitants are scattered and nomadic, though greatly aided by their domestic animals. The desert barrier prevents them from learning from others, and hence they preserve many ancient customs. The oases, however, ivere cradles of ancient civilization, because (1) agrictdture ivas possible ; (2) it was necessary to provide food for the unfavorable seasons; and (3) the desert protected the inhabitants from invasion. 258. Influence of Mountains. — There is no part of tlie world where, in so short a distance, there are found races so different as those on the north and south sides of the Himalayas. These mountains have served as great walls (p. 106), hindering the migration of man as well as of animals ; and it was partly because of their protection that the people of India became so civilized in very ancient times. Yet even these mountain barriers were crossed, although with great difficulty. Much the same is true of the Alps, whose protection helped to make the powerful Roman Empire possible. When their country is invaded, people often retreat to mountains; for there is little about mountains to attract invaders, and entrance is difficult, while the passes and valleys are easily defended. For these reasons the Welsh and Scotch, who occupied the more mountainous parts of Great Britain, were far less affected by the inroads of invaders than the inhabitants of other sections of the island. To this day their ancient language is spoken, and sermons are even preached in it. In the Pyrenees there is a small group of people, called the Basques, who still retain an ancient language no longer spoken by others. In the single small country of Switzerland four languages are now spoken, — German, French, Italian, and Rsetho-Romisch dialect. Among mountain people ancient customs, as well as languages, are preserved. For example, homespun is still used in the mountains of eastern Kentucky; and peculiar, old-style costumes are worn by Swiss mountaineers and inhabitants of the Black Forest mountains of Germany. Such places, like deserts, are among the last to be reached by new customs. Mountain people are brave and hardy, for their life is one of hardship, and there are many dangers. The open-air life, with plenty of space and freedom, develops a love of freedom. They desire to be left alone, and resist attempts at conquest. It is for such reasons that little Switzerland, notwithstanding many efforts to seize it, has been able to remain independent. bummary. — Mountains are harriers, protecting people from invasion; they are places of retreat before invaders; in tJiem ancient languages and customs linger ; they develop) a brave, hardy, freedom-loving race. 259. Influence of Coast Line. — Closed seas and irregular coasts, having quiet water, encourage fishing and commerce. It is along such coasts, therefore, that navigation has developed. The Mediterranean and the irregular Grecian coast illustrate this; also the irregular Scandinavian coast, with its many narrow, quiet fiords (p. 209). Here developed the brave, hardy Norsemen, who ravaged the coast of western Europe, and even visited America, before the time of Columbus. The British nation has become " mistress of the seas " because of the favorable position and coast. No part of the British Isles is far from the sea; there are innumerable bays and harbors; and many of the inhabitants have engaged in fishing. The separation from the mainland has been of the highest importance, for it has prevented invasion by land and has made commerce by water necessary. Furthermore, these small islands are unable to supply food enough for the large manufacturing population that has developed there. To bring food, and to carry away manufactured products, calls for ships ; and to protect these and the coast from attack, demands a navy. Colonies were established as a source of food and raw products for manufacture ; they also served as a market for manufactured articles, and commerce with them became great and mutually beneficial. As a result of these facts, and the presence of coal and iron for manufacturing, the British nation has become the greatest sea power in the world, and has come into possession of the largest amount of territory that any nation has ever controlled. ment oj navigation. Tlie British nation has become the greatest sea jyoiver, and the x>ossessor of the largest amount of territory, of all nations, as a result of its island condition, its irregular coast, and the fact that it needed to import food and raw products for manufacture, and, being on an island, was obliged to bring them by water. Early settlements were naturally first made along the coast, because this was the first place reached. Although the natives were finally pushed aside, for a while aided by the mountain and forest barrier, they held back the westward advance of the pioneers. Thus the settlers continued to live along the coast ; and in 1790, when the West was a vast wilderness crossed only by Indian trails, it was possible to travel by stage from Portland, Me., to Virginia, stopping each nisht in a good-sized village. The Spanish and French settlements were far more scattered, for the Spanish had two coasts along which to travel, and the French the great interior waterways. Therefore, when the French and Indian war came, the English, being closer together and able to unite, had a great advantage. The success of the Revolution was also in large part due to the fact tliat the Colonists were centered along the coast. The mountains were finally crossed along the water gaps, through Cumberland Gap to Tennessee and Kentucky, and along the Mohawk Gap to the Great Lakes. When the way to the interior was wejl opened, migration was rapid, because the soil was good, the climate favorable, the surface clear of forest, and the land free to all. Soon the central plains developed into a great agricultural, mining, and manufacturing section. The water gaps and waterways are still the leading routes to i:his interior. West of the prairies was another great barrier, in the form of arid plains and plateaus, extensive deserts, and lofty mountain ranges. How great a barrier this was is seen from the fact that, when gold was discovered in California, large numbers preferred to travel entirely around South America rather than undergo the danger and hardship of a wagon trip across the continent. Now several lines of railway cross the mountains; there are mining cities in the mountain valleys; and irrigated farms dot even the desert. Man has so overcome these barriers that the continent is crossed in a few days with all the comforts of modern railway travel. Our country has developed wonderfully, and in a century has changed from a weak nation, struggling for existence, to one of the great world powers. This growth is not the result of a mere accident ; nor is it due to a single cause. The invigorating climate encourages work, and in fact requires it ; and intelligent labor secures great reward. In a new country there are wide opportunities for those who work hard, and this fact has helped make the American people energetic. Mineral, farm, and forest products may be obtained in great variety; and physiographic conditions, as well as the wise government under which we live, are favorable to their development. It is no wonder that the United States has advanced so rapidly ; and the present century should see still more wonderful advancement. Summary. — TJie climate, resources, government, and coast line of the United States are favorable to 2^^^ogress. Hie early settlements along the coast, and the interference ivith westward spread, caused by the Indians and mountain barrier, helped make the English successful in ivar ivith Frtince, and the colonists in the Mevoliction against the mother country. The mountaiyi barrier was first crossed along the water gaps, and the fertile, open prairie tvas then quickly developed ; but the great western barrier of desert and mountain held back further j^rogress until after the discovery of gold in California. Our rajnd development has depended on the energetic people, wise government, and vast resources; ajid since the foun^ dation is solid, our prosperity promises to continue. 245. Food Supply. — Basis of invention; primitive implements; present use; parts of plants eaten; instances; reasons for cultivation; importance of domestication ; farming at present; dependence on farmer. 247. Shelter. — (a) Primitive shelters: Eskimos; Indians ; nomads ; sod houses ; tropical shelter ; caves, (b) Building materials : first use ; wood; stone; mortar; sun-dried brick; baked brick, (c) Fire: need of it ; first importance ; later uses ; result of these uses. 249. Location and Growth of Cities. — (a) Primitive man : reasons for communities : savages ; advantages of villages. (&) Government : village chief ; exTeusion of power 5 origin of modern government. (c) European towns: castles; gathering of people about them; present condition, (d) Modern cities: capitals; industries in large capitals; cities at junction of trade routes ; on rivers ; lake ports ; seaports ; seaports at mouths of rivers ; effect of water power; of mining. 250. Development of Commerce. — (a) Exchange : desires of primitive people ; methods of gratifying them ; early commerce, (b) Greeks ; favorable location ; colonies ; extension beyond Mediterranean, (c) Discovery of new lands : reason for exploration ; results, (d) Eif ects of commerce : exchange; need of money; use of gold; spread of civilization; '■iarly writing ; alphabet ; electricity. 251. Influence of Man on Nature. — Life; forest removal, — effect on rivers, on soil ; changes in stream courses ; irrigation ; lakes ; work along Reacoast; borings; mines; quarrying; tunnels; roads; plowing; independence of man ; use of surroundings. 252. The Spread of Man. — Resemblance to animals ; superior intelligence ; use of boats ; of clothing and shelter ; slow spread ; rapid spread ; conquest; discovery of new lands; aid of commerce. 256. Man in the Temperate Zone. — (a) Reasons for civilization : abundant food ; need of storing food for winter ; need of clothing and shelter; varied climate and land form. (&) Nature of advance: cultivation of crops; domestication of animals; use of implements; of metals ; art of building ; use of fire. 257. Man in the Desert. — (a) The desert itself: comparison with Arctic ; domestic animals ; nomadic characteristics ; effect of desert barrier, (b) On oases : agriculture ; cradles of civilization ; reasons for development of civilization, (c) Euphrates and Nile : early civilization; its spread; present condition, (d) American Indians. 258. Influence of Mountains. — (a) Barriers ; races on two sides of Himalayg-s ; protection to India; Alps, (b) Retreats: reasons; Welsh and Scotch ; Basques; Switzerland; ancient customs. (c) Mountain people : character ; love of freedom ; Switzerland. 259. Influence of Coast Line. — (a) Closed seas : Mediterranean. (&) Irregular coasts : Greece ; Scandinavia, (c) British nation : nearness to sea ; irregular coast ; fishing ; island condition ; food supply ; colonies ; commerce ; coal and iron ; great importance. 260. United States. — (a) Favorable conditions: climate; resources; government; coast line; ocean, (b) Mountain barrier: first settlements; natives ; barrier to westward movement ; condition in 1790 ; Spanish ; French; French and Indian war; Revolution, (c) Interior: crossing barrier ; development of interior ; present routes to interior, (d) Western barrier: nature; difficulty of crossing; present condition, (e) Growth of country : climate ; energetic people ; resources ; government ; future. 245. What simple implements were early used? Why? Why were plants cultivated? What parts are used? Give examples. Of what importance is domestication ? Of what present importance is agriculture ? 249. Why do men gather in centers? Illustrate. What influence has this on government? What was the condition in Europe ? What great European cities are capitals? What else accounts for their growth? What situations especially favor the growth of cities? Give instances. In what several connections is London mentioned? 250. What is the nature of commerce among primitive peoples? How was early commerce carried on ? What was the nature of ancient coni' merce between Asia and Europe ? What influence had the Mediterranean ? What effect had the Mohammedans? On what does the use of money depend? Why is gold used? State other effects of commerce. 2.53. What is the cause of differences among men? Name the four races. Where is each mainly found (Fig. .544) ? Why are the boundaries not sharp ? What about the spread of the different "races ? 257. What is the condition of man in the desert ? Why are primitive customs preserved? Why were oases favorable to the development of early civilization? Of what importance was this in the Old World? What was the condition in the New World? 258. What are the effects of mountains as barriers? Why are they places of retreat? Give illustrations of the influence of this on language. On customs. What effect have mountains on character ? 260. What conditions are favorable to the advance of the United States ? What were the nature and effects of the barrier west of the coast? Where was this barrier crossed ? What was the result? What barrier was found farther west ? How has it been overcome ? Upon what has our progress as a nation depended ? Reference Books. — Shaler, Nature and Man in America, Scribner's, Sons, New York, 1891, $1.50; Peschel, Races of Man, Appleton & Co., New York, 1876, $2.25 ; Lubbock, Origin of Civilization, Appleton & Co., New York, 1895, $5.00; Keane, Ethnology, 2 vols., Macmillan Co., New York, 1896, $2.60; Man, Past and Present, Macmillan Co., New York, 1899, $3.00; Brintox, Races and Peoples, McKay, Philadelphia, 1890, $1.50; Ripley, Races of Europe, 2 vols., Appleton & Co., New York, 1899, $6.00; Ratzel, The History of Mankind, 3 vols., Macmillan Co., New York, 1896-99, $4.00 a volume ; Gibbins, History of Commerce in Europe, Macmillan Co., New York, 1891, $0.90 ; Guyot, The Earth and Man, Scribner's Sons, New York, 1893, $1.75; Marsh, The Earth as Modified by Human Action, Scribner's Sons, New York, 1885, $3.50; Mackinder, Britain and the British Seas, Appleton & Co., New York, 1902, $2.00. APPENDIX A. REVOLUTION OF THE EARTH. 1. Apparent Movements of the Sun. — In addition to tlie daily rising and setting of the sun there is a slower change in its position which can be detected by noting the point of sunrise or sunset for a week or two. In the north temperate zone, the sun rises exactly in the east and sets due west on March 21 and September 23. From March to September sunrise and sunset are north of true east and west, and the days are longer than the nights. But from September to March the sun rises and sets south of due east and west, and the nights are then longer than the days. The midday sun also changes in position. It is higher in summer than in winter, but is always in the southern half of the heavens. In the southern hemisphere the same changes occur in the opposite season ; but there the midday sun is always in the northern half of the heavens. 2. Experiment to Illustrate Revolution. — One or two simple experiments will aid in a better understanding of the way in which revolution (p. 5) causes these apparent movements of the sun. Place two balls in a tub of water (Fig. 548), one in the center to represent the sun, the other off to one side to represent the earth. The water surface represents the plane of the ecliptic, or the plane in which the earth moves in its revolution around the sun. If the earth ball is moved around the central ball, its path will represent the orbit of the earth in its revolution. A needle inserted in the earth ball represents the position of the earth's axis. When the ball is so placed that the needle projects straight up into the air, the axis of the ball is perpendicular to the water surface ; if the axis of the earth were in a similar position, it would be perpendicular to the plane of the ecliptic. Now turn the earth ball until the needle is inclined as in Figure 548, which is the same angle as that at which the earth's axis is inclined. The earth is inclined 66h° to the plane of the ecliptic, or 23 ^° to a perpendicular from that plane. Float the earth ball around the central ball, always keeping the needle axis inclined at . the same angle, and you will see quite clearly in what position the earth moves around the sun. the sun. These points represent spring and autumn. 3. Rotation and Revolution. — The manner in which revolution causes the sun's position in the heavens to change may be understood by another simple experiment. Let a globe or ball represent the earth, and a lamp or candle the sun. Carry the globe in a circular path around the light, being careful to always keep the axis inclined at the same angle. When the position is that of summer, the full rays of the lamp illuminate the northern half of the globe and reach beyond the l)ole. So in the case of the earth, when it has reached the summer position in its orbit, the sun's rays reach beyond the North Pole, and illuminate all the space within the Arctic Circle (Fig. 549). This circle is located 23^° from the pole because the sun's rays of midsummer (June 21) reach that distance beyond the North Pole. They reach that far because this is tlie amount that the earth's axis is inclined. Still holding the globe in this position, observe the conditions at the opposite end of the axis, or the South Pole. Even when the globe is rotated, no light reaches that portion. This is also true of the earth in summer, for then the midday sun just barely appears on the Antarctic Circle, 23i° from the South Pole. All bathed in light Fig. 550. — The sun at midnight in the Arctic in summer when the region within the Arctic circle is lighted during the entire rotation. its orbit, it is divided into a dark and a light half by a plane passing from pole to pole (Fig. 552). At these times, the equinoxes (equal nights), all over the earth day and niglit are each 12 hours long. One period is called -yeniaZ (spring) equinox, the other autumnal (autumn) equino?:. During the equinoxes, when the sunlight just reaches each pole, the midday sun is directly above the equator, A-fter December 21, in all parts of the earth, the sun appears to be slowly moving northward, and the sunlight slowly creeps over the curvature of the earth into the Arctic. After the earth has passed its summer position, the sun seems, from tion turns one hemisphere toward the sun for a time, then away from it. These annual changes recur so regularly that, in all the time of human history, there has been no noticeable change. Suggestions. — (1) Study Sections 2 and 3 at the same time that you are yourself performing the experiments described. (2) Make careful observations of the change in. the sun from day to day. On a platform, or table, placed where the sun reaches it from morning till night, draw intersecting north-south (p. 419) and east-west lines. Where they cross drive a long knitting needle into the table. Once a week at noon mark on the north-south line the point to which the needle shadow reaches. Also mark the point reached by the shadow just after sunrise or just before sunset. What movements of the sun cause these changes? Observe also the exact place where the sun sets each week. (3) In what direction does. your shadow point at noon? In what direction would it point in South Africa? At each tropic, in the middle of March, June, September, and January? At the equator? What is the direction of a shadow at noon in summer in the Arctic? At midnight? Are .«"ch shadows longer or shorter than in the temperate zone? 2d APPENDIX B. LATITUDE AND LONGITUDE. 1. Latitude. — The most convenient method of locating points on the spherical earth is by imaginary circles extending in opposite directions. Any point can then be definitely located by the intersection of such circles. These are called circles of latitude and longitude^ names given when the extent of the world was not known, and one direction (longitude) was supposed to be the long direction, the other (latitude) the broad direction. For measurement of latitude imaginary circles are extended in an east-west direction. The largest circle (about 25,000 miles), the equator, extends around the earth midway between the poles. Other circles parallel to this, and called parallels of latitude, are located at intervals between the equator and either pole. As their distance from the equator increases, these circles diminish in diameter (Fig. 554) until, at the poles, a circle of latitude is reduced to a point. For convenience in use the parallels are numbered. From the equator to the north pole there are 90 parallels, numbered as degrees (indicated by the sign °) ; there are also 90 from the equator to the south pole. The equator is called 0° latitude ; the north pole, 90° north latitude (abbreviated N. Lat.); the south pole, 90° south latitude (S. Lat.). The Tropic of Cancer is 23i° N. Lat. ; the Arctic Circle, m^° N. Lat. ; the Tropic of Capricorn, 23-1-° S. Lat. ; the Antarctic Circle, &Q^° S. Lat. Which parallel of latitude is nearest your home ? Since there are 180° from pole to pole there are twice that number, or 360°, in a complete circle extending around the earth across the poles. It is customary to divide circles into 360°. This is a convenient number because it is exactly divisible by so many numbers. sphere (p. 3). It is -g^-g- of the circumference. Divide the circumference of the earth (25,000 miles) by 360. At the equator a degrees is about 68.7 miles, at the poles about 69.4 miles. Fig. 554. — To show how the meridians converge at the pole. Trace the 0° meridian to the opposite side of the globe. What is it numbered there ? being -^-^ of the earth's circumference. In latitude 40°, which is a much smaller circle than the equator (Fig. 554), a degree of longitude, gi^ of that circle of latitude, is only about 53 miles. In latitude 60° a degree of longitude is about 34.7 miles; and at the poles, where all the meridians come together, a degree of longitude has no length. The circles of longitude are numbered as degrees, there being 360 degrees. Since there is no such natural starting point as the equator, there is no general agreement as to where the numbering of meridians shall begin. Most nations, however, have adopted as the 0°, or pr^'me meridian, the circle that passes through the Greenwich Observatory, just outside of London. From this meridian the circles are numbered up to 180° both east and west. New York is 74° W. Long. Jerusalem is 35° E. Long. What is the nearest meridian to your town ? Fig. 556. — Map to illustrate standard time in United States. The meridians 75°, 90°, 105°, and 120°, extend throujjh the middle of the four time belts. The irregular boundaries are due to the fact that railways have chosen convenient points on their lines to make the change. in time. Formerly, places in United States kept local or solar time, and even neighboring cities might have a different time. This caused so much inconvenience that it was agreed to adopt a standard time, by which the time changes one hour for every 15° of longitude. Now in traveling across the continent one need change his watch only three times (Fig. 556). LATITUDE AND LONGITUDE. 405 If longitude may be used to determine time, it is evident that time may be used to determine longitude. Ships crossing the ocean are able in this way to determine their position. They start with an accurate clock, or chronometer, set to Greenwich time. By means of an instrument, the sextant, an officer observes the sun to determine the local noon, that is, the time when the sun has reached its highest position. Comparing this local time with that of the chronometer, it is easy to tell just how many minutes' difference there is between Greenwich time and that where the ship is. Knowing that one hour's difference means 15° of longitude, the longitude of the ship is readily determined. Suggestions. — (1) To understand the need of circles of latitude and longitude, try to locate New York City without these. Do the same by use of latitude and longitude. (2) By tying the ends of strings together make three circles so that one will fit over the equator of a globe, one over parallel 45°, and one over parallel 60°. Make three other circles for meridians and place them on the globe, one over 0° longitude, one over 60° west longitude, one over 120° west longitude. With ink, mark on each of tlie latitude strings the place where two of the meridians cross. Take the strings off, and measure the diameters of each. How do the diameters of the meridian strings compare with the equator string? How do the three latitude strings compare in diameter? Measure the distance between the ink marks made on the latitude strings. How do these distances compare ? This shows how the length of degrees of longitude varies. (3) Get a local surveyor to explain and illustrate the method of determining latitude and longitude. (4) Recall your previous study of standard time (see Second Book of Ta^r & McMurry's Geographies, p. 116). If the earth were flat, what would be tne effect on time ? To answer this, imagine a table top to represent the earth. Raise a lighted candle up to the edge to represent the rising sun. How much of the table do the rays reach at once ? Is any more of the table reached as the candle is raised higher ? Now, to represent part of the globular earth, place a curved object on the table top; for example, a large sheet of cardboard or blotting paper, resting on books or dishes. How much of this curved surface is lighted when the candle is raised ? Is more lighted as the candk is raisea higheV? MINERALS This appendix should be studied ivith an accompanying use of mineral specimetis. Each mineral should be carefully examined to note its color, hardness, cleavage, luster, aud crystal form. The text may be referred to, but each student should have a set of specimens and be expected to find the features visible. A MINERAL may be defined as a single element, or two or more elements chemically combined, forming a part of the earth's crust. Some, like suli^hur, consist of one element; but most minerals are formed by a combination of several. For example, quartz is made of silicon and oxygen; one of the feldspars contains silicon, oxygen, aluminum, and potassium. There are about 2000 known minerals, of which only one or two hundred are abundant, while less than a dozen are common in most rocks. The more important of the rock-forming minerals are described below. 1. Common Rock-forming Minerals. — Quartz. — This, the most common of minerals, is present in many rocks and soils. It is made of silicon and oxygen, forming silica (SiOg). These elements are so firmly united that quartz does not decay ; but it \9 slightly soluble in underground water. It has a glassy appear ance, or luster, and varies in color from clear glassy to milk}? white, blue, rose-colored, red, and variegated. Agate, opal, jasper, and chalcedony are varieties of silica. It is so hard that it will scratch glass, but is brittle and easily broken, having a shelly or conchoidal fracture, like glass. When it crystallizes it takes the form of a six-sided (hexagonal) prism terminated by a six-sided pyramid. The Feldspars. — There are a number of kinds of feldspar, each formed by the union of several elements, and all nearly as hard as quartz. Crystals are not common. Cleavage planes, extending through feldspar, cause it to break along smooth faces. Unlik§ quartz, feldspar is not soluble. When exposed to air and water, however, it decays, becoming dull and whitish ; and, if exposed long enough, the hard mineral crumbles to a whitish clay, or kaolin. Many soils contain decayed feldspar, and some of the best pottery clays are kaolin. Thus, though insoluble and nearly as hard as quartz, its decay makes feldspar less durable. Calcite (calcium carbonate), like quartz, varies greatly in color. It often has a perfect crystal outline ; and since it has cleavage in three directions, when broken it is apt to take the form of a rhomb. It has a pearly luster. Unlike quartz and feldspar, calcite is so soft that a knife readily scratches it. Moreover, it is one of the most soluble of common minerals ; and the cleavage planes afford opportunity for water to enter and dissolve the mineral. For these reasons a calcite rock is far less durable than one made of feldspar and quartz. The mineral dolomite resembles calcite ; but it is less soluble, and has a different chemical composition. Calcite contains calcium, carbon, and oxygen, and is, therefore, carbonate of lime (CaCOg) ; dolomite has magnesium in addition, and is, therefore, magnesian carbonate of lime ( (CaMg) CO3). The Micas. — There are a number of different minerals belonging to this group, all having a complex chemical composition. Some are black, some colored, and some so colorless that they are used in stove doors as " isinglass." Two of the most common forms are biotite and muscovite, the former dark colored, the latter light. All are easily scratched with a knife, and all have so remarkable a cleavage that they readily split into thin sheets. Some micas decay readily ; but others so resist decay that they occur as shiny flakes in soils and some rocks, such as sandstones and shales. Hornblende is a black mineral of complex chemical composition, common in some granites and lavas. It is hard, has a bright luster, is often crystalline, and has well-defined cleavage. When exposed to air and water it decays, one of the products being an iron compound which stains the rock. Iron is one of the elements in this mineral. Augite, found in many lavas, resembles hornblende in several respects, and in small grains is difficult to distinguish from it. Its chemical composition, crystal form, and the angle at which instead of black. Like hornblende it decays readily. Iron Ores. — Small quantities of iron are present in many minerals and rocks, and the yellow and red color of soils is due to iron stain. Among the iron minerals are several which are of value as ores. Magnetite, a compound of iron and oxygen (FegO^), is black, hard, heavy, usually crystalline, and has a metallic luster. A magnet will attract the grains. Hematite (FegOg), another oxide of iron, is red and either earthy, crystalline, or in smooth, rounded masses. Like other iron ores it is heavy. The red coloring of soils is due to a hematite stain. Limonite is yellow, and common iron rust and the yellow color of soils are due to this mineral. It is an iron oxide with water, or a hydrous oxide (2Fe203 SHgO). It is easy to determine an ore of iron by scratching it on a piece of white quartz, or of broken china. Siderite, the carbonate of iron (FeCOg), is a heavy brownish mineral, resembling calcite in general appearance. Iron pyrite, or pyrites, the sulphide of iron (FeSg), is not useful as an ore. It is a hard, heavy, golden yellow mineral, sometimes mistaken for gold, and hence called "fool's gold." It often occurs in perfect cubical crystals. Gypsum, the sulphate of lime, occurs in small grains in many rocks, and sometimes in beds. It is so soft that it can be scratched with the finger nail ; and, being soluble, is often present in ^' hard " water. The color varies, but is often white. Sometimes it is well crystallized, then having such perfect cleavage that it splits into thin flakes ; but, unlike mica, the flakes are not elastic. Minerals in Rocks. — The tables (pp. 410-413) show that the common rocks are made chiefly of the minerals described above. Other minerals, while abundant in some localities, are relatively rare in the rocks of the earth ; but some of the rarer minerals, such as the ores of gold, silver, copper, etc., are of great value to man. ROCKS. 2. Classification of the Common Rocks. — Rocks are mixtures of minerals, and are not usually of definite chemical composition. They may be classified in three great groups : — below. 3. Sedimentary Rocks. — Fragmental or Clastic Rocks. — By the disintegration of rocks, fragments of all sizes, from clay to bowlders, are detached. When assorted by water these are deposited in layers (p. 33), the pebbles forming gravel beds, the sand, sand beds, and clay, clay beds. Rock fragments may also be brought by glaciers, by wind, and by volcanic explosions, which supply ash and pumice. These fragmental, or clastic, materials may be cemented into solid rock by the deposit of mineral substances carried by underground water (p. 39). Consolidated gravel beds, called coyiglomerates, are composed of whatever minerals were in the rocks from which the pebbles are derived. Consolidated sand beds, or sandstones, usually consist of small quartz grains, quartz being the most indestructible of common minerals. Some sandstones are well cemented and firm, others friable ; and iron oxide cement often gives to them red, yellow, or brown colors. A well-cemented sandstone or conglomerate, with much quartz in it, is one of the most durable of rocks, resisting denudation so well that it forms peaks and ridges, as in the Appalachians. Since quartz does not decay and produce plant food, as feldspar and many other minerals do, sandstones make poor soils. Shale, the most common clay rock, varies in color from black to blue or light gray. Because of the presence of large numbers of flattened particles, often small mica flakes, it splits readily along the bedding planes. Shales split so easily, and are so soft, that they readily disintegrate, and among mountains are, therefore, usually found in the valleys. Soils produced by the decay of shale are much more fertile than sandstone soils. Chemically formed Rocks. — The decay of minerals produces many substances which underground water dissolves. After being carried for a while, some may be deposited. For example, carbonate of lime is being deposited as stalactites in caverns (p. 60) and as calcareous tufa around the Hot Springs of Yellowstone l^ark (Fig. 243). On the coast of Florida and in Great Salt Lnke it is also being precipitated in small, romiflod. or ooh'tio gniii^s (p. 163). Salt is being deposited on marshes bordering Great Salt Lake and the Caspian Sea ; and, by the drying up of salt lakes, as in western United States, gypsum has been precipitated. Deposits of silica around the geysers of Yellowstone Park form silicious sinter (Fig. 244) ; and bog iron ore is being accumulated where certain spring waters, on reaching the air, are forced to deposit iron. Underground water has deposited many veins of valuable metal in fissures in the crust (p. 132). Made of plant remains. Organic Rocks. — Carbonate of lime, dissolved in water, supplies many animals with materials for shells, or limy framework. Where such animals aie abundant, as in coral reefs (p. 217), their limy remains often accumulate as thick beds of limestone. Many such beds have been raised to form part of the land. Limestone, being both soft and soluble, is worn away to form lowlands ; and, since it is rich in plant food, it forms a fertile soil. This is illustrated in the broad, fertile limestone valleys which extend among the mountains of New England and New Jersey, and thence through the Shenandoah valley of Virginia to Tennessee. Dolomite is not so easily worn, and, when very massive, sometimes forms mountains. One very rugged section of the Alps is known as the Dolomite Alps. Eemains of plants accumulate in swamps, as in peat bogs (p. 168), where the water retards decay. When such swamp deposits have been covered with beds of other rocks, they gradually lose their water and gases, and change to coal (p. 170). The early stages of this change form lignite, later stages bituminous coal. 4. Igneous Rocks. — These rocks, which have risen in a melted condition from within the earth, have cooled either on the surface, as near volcanoes, or below the surface as intruded masses in the crust (p. 126). In the latter case, the overlying blanket of strata has allowed the lava to cool so slowly that the minerals have had opportunity to grow to fair size, giving these intruded rocks a coarse crystalline structure. In many places denudation has worn the surface down to these intruded igneous rocks. Grayiite(¥\g. 33). — Granite is the most common intruded igneous rock. Of what minerals is it composed (see table p. 412)? The structure is so coarse that the different mineral gr-^ins are plainly seen and easily distinguished. The color of granite varies according to the color of the feldspar, being commonly light and either gray, grayish green, red, or pink. It is a valuable building stone, and is one of the hardest and most durable of rocks, resisting destruction so well that, in the wearing down of mountains, it is commonly left standing as peaks. Syenite, a coarse-grained rock, resembles granite, but has no quartz. Gabbro, norite, and anorthosite, found in the Adirondacks and in Canada, are hard, intruded igneous rocks, less common than granite. Diorite and Diabase are dark-colored igneous rocks without quartz, the color being due to dark-colored minerals, especially hornblende, augite, and mica. Diabase, also called traj), is often so fine grained that the minerals cannot be distinguished without a microscope. The Palisades of the Hudson and the trap hills of New Jersey and the Connecticut valley are diabase. are light, the last two, dark colored. In most cases, erupted lavas have cooled too rapidly for the mineral grains to grow large enough to be distinguished by the eye alone ; but large porphyritic crystals are often scattered through them, having been formed while the rock was still molten, then inclosed in the fine-grained mass, which quickly cooled when the lava reached the air. and they are then called natural glass or ohsidiayi. A porous structure is given lavas by the expansion of steam, which forms cavities ; and rapid expansion of the steam blows the lava into bits, forming pumice (Fig. 33) and volcanic ash (p. 122). The ash from the Martinique eruption (p. 113) was andesite lava blown to pieces by steam ; the lava of the Hawaiian volcanoes is basalt. Much of the country west of the Rocky Mountains is covered with basalt, andesite, and other lava rocks erupted from ancient volcanoes and fissures. These lavas, having many cavities for water to enter, and being made of minerals that decay readily, are soon covered with a fertile soil, for the minerals of lava are rich in plant food. 5. Metamorphic Rocks. — Any rock subjected to great pressure, as m mountain folding, and to the action of heated water, is certain to suffer change or metamorphism. In. sandstone, for example, silica may be deposited around the grains until the rock becomes almost one solid mass of quartz, called quartzite. Shale, when altered by metamorphism, changes to slate. New minerals are then developed, which have cleavage so perfect that the slate is caused to split, or cleave readily. By metamorphism limestone is changed to crystalline calcite, as in the case of white marble. In the Appalachian Mountains (p. 109), coal has been metamorphosed to anthracite. In Ehode Island, where mountain folding was even more intense, coal has, in some cases, been changed to graphite, which is pure carbon. When subjected to metamorphism so intense that the minerals have recrystallized, some rocks are altered to gneiss. Gneiss resembles granite ; but there is a slight banding of the minerals (Fig. 33), due to the fact that they have developed along lines of least resistance — that is, at right angles to the pressure. Where the banding is so distinct that the rock readily cleaves, it is a schist. Gneisses and schists are durable crystalline rocks, found in regions of intense mountain folding. Suggestions. — (1) Collect minerals from your neighborhood and study them. Dana's Minerals and How to Study Them is a good book of reference. (2) Collect rocks from the ledges, bowlders, quarries, and stone yards. If you live in a part of the country reached by the ice sheet (Fig. 270), you will find a varied store of rock specimens in the gravel banks. See how many kinds you can collect. Study their characteristics ; place them in one of the three groups and, if possible, give them their proper names. The teacher can systematize this work and make it of great disciplinary value. (3) Place pieces of quartz, feldspar, and calcite in weak hydrochloric acid. Which .■ .ittacked by it? Water in the earth is often weakly acid, and in this state attacks minerals. (4) Grind up some mica, mix with sand, and stir in water. After the sediment has settled, notice the position of the mica flakes. It is for this reason that shales split readily along the bedding planes. (5) To which of the three groups do the rocks of your neighborhood belong? What kind or kinds do you find ? Of what are they made ? Are they hard or soft? Do they make rich or poor soil? If your home is in a valley, see if the rocks on the hills are different. What are the differences ? Do they help account for the hills and valleys ? Reference Books. — Dana, Minerals and How to Study Them, Wiley & Sons, New York, 1895, .\|1.50 ; Kemp, Handbook of Rocks, D. Van Nostrand Co., New York, 2d ed., 1900, ^1.50. APPENDIX D. GEOLOGICAL AGES. While it is impossible to tell the age of the earth in years (p. 45), geologists have divided the strata into stages, or periods, and have determined their relative age. This is made possible by the fossils the strata contain. For example, there was a time when no animals higher than fishes lived on the earth; and if strata contain remains of birds, it is certain that they were not deposited in those ancient times. Careful studies of fossils, in all parts of the earth, have so clearly revealed the history of the development of life that, on examining the fossils in a rock, geologists can now tell in what period it was formed. To the different periods names have been given, some of the most common of which are placed in the following table : Cretaceous. Birds begin to be important; reptiles continue ; and higher mammals appear ; land plants and insects of high type. APPENDIX E. TIDES. The full explanation of tides is considered too difficult and complex for statement in so elementary a book. It is known that they are caused by the attraction of gravitation which both sun and moon are exerting on the earth ; but the moon is more effective in this than the sun. oceans. A second high tide is formed on the opposite side of the earth. In this way the ocean is distorted into a somewhat elliptical form. If the earth were all water, the attraction of the moon would change it to an ellipse ; and, as the earth rotated, the form of the ellipse would constantly change to keep its axis pointing toward the moon.^ That is to say, two waves would constantly be passing around the earth, following the moon. To understand this shape attach a rubber ball to the floor and, by a string on the upper side, pull until the ball loses its spherical shape. Tidal waves are produced by the sun in the same way as by the moon ; but, although the sun is so much larger than the moon, gerated. 1 There is more to the tidal explanation than the mere pull of gravitation; there is also the effect of centrifugal force. However, unless the teacher, because of special interest, wishes to enter into a full study of tides, it does not seem well to introduce this complex question. moon occur where low tides are caused by the sun ; consequently the tidal range is much less. These tides of low range are called neap tides. Each lunar month, that is every 29^ days, there are two spring and two neap tides. Another cause for variation in tidal range is the distance of the moon. The moon revolves around the earth in an ellipse, and when it is nearest to the earth, or in perigee^ the lunar tide is higher than when it is farthest, or in apogee. Because of these variations in the relative position of sun and moon, and in the distance of "the moon, the tidal range varies greatly. There is also an irregular variation due to wind (p. 271), which sometimes piles the water up in bays, causing it to overflow wharves and low land that the tide itself never reaches. In the United States, as in other regions, a bar or needle of magnetized steel, so suspended that it freely swings horizontally, will point north and south. An instrument having such a needle is a compass. Throughout most of the country the compass needle points a little to one side of a true north and south line. In central western Greenland the needle points westward, in northern Greenland, south westward. The place toward which the compass needle points is known as the north magnetic; pole, and is located north of Hudson Bay and west of Baffin Land. Within the Antarctic Circle, between New Zealand and the South Pole, there is a similar region known as the south magnetic pole. It is because of these centers of magnetism that the compass is so valuable that sailors depend upon it for" determining the course of their ships, and the steersman always has one in plain sight. In the Arctic the comj^ass is much less useful, for, though nearer the magnetic pole, the needle is less sensitive and more easily deflected by outside influences, such as the presence of iron. The reason for this fact is that the cause for the attraction of the needle lies beneath the earth's surface. This is proved by so suspending a needle that it will freely swing, or dip, vertically. At the magnetic pole, the needle of such a dip compass points directly downward ; near the equator it swings horizontally ; part way between the pole and equator it points toward the earth at an angle. From this it is evident that, the nearer one goes to the magnetic pole, the stronger becomes the downward attraction and the weaker the horizontal pull, and, therefore, the less useful the compass. Along a line extending from South Carolina to Lake Superior, magnetic north, or north by the compass, is the same as true north ; that is, the compass points toward the north pole. East of this line the compass points to the west of true north, northern Maine showing a difference between magnetic and true north, or a declina- MAGNETISM. 419 Hon, of 21°. West of the line of no variation, or no declination, the needle points to the east of true north, in northern Washington reaching an east declination of 23°. A map showing lines of equal magnetic declination is an isogonic map (Fig. 560). The amount of declination slowly changes, so that a map made for one year is not strictly accurate for the next year ; but the change is so slow that a long time is necessary to produce a marked difference. The cause for these changes, and even the cause for the magnetism of the earth, is unknowai. It is some condition within the earth, far from the surface, possibly in some way connected with the heated interior. All that is positively known is that, for some reason, the earth acts as a great magnet. The aurora horealis, or northern lights, is in some way connected with this magnetism. A similar phenomenon, the aurora australis, is found in the southern hemisphere. The aurora is not common in the United States, though sometimes it becomes visible, and even vivid. The northern sky is then aglow with an arch of strange light, with streamers darting to and fro. In the far north the aurora becomes much more vivid, and maybe seen night after night. The cause of the aurora is unknown, though it seems to be due to faint electrical discharges in the upper air> resulting from some influence of the earth's magnetism. Suggestions. — (1) Learn to read a compass (a small one is quite inexpensive). Determine the true north and south line. This can be done by setting up two poles in line with the north star. With a compass, observe the difference between true and magnetic north. (2) Place a bar of iron near a compass. Is the needle disturbed? Try the effect of a magnet. (3) If you have ever seen an aurora, describe it. Have you ever read a description of one in a book of Arctic travel ? MENTS. 1. Thermometers. — The ordinary thermometer is a sealed glass tube with a cavity of small diameter, ending below in an expansion, or bulb, in which there is mercury. The mercury can rise and fall freely in the tube because there is no air in it. The principle of the thermometer is that liquids, like mercury, expand and require more space when warmed, but, when cooled, contract and take up less space. As the temperature changes, therefore, the mercury in the bulb causes a tiny thread of mercury to rise and fall in the tube. Other liquids may be used ; in fact, alcohol is used when thermometers are to be exposed to cold greater than the freezing point of mercury (— 40°). Thermometers are graduated in degrees, the division commonly used in America and England being the Fahrenheit (Fahr.) scale. In this, the boiling point of water is placed at 212^ and its freezing point at 32°. This is not nearly so simple a scale as the Centigrade (Cent.) which i& when warmed and contract when cooled, eters may be made of metal strips connected with a hand that moves -iver a graduated dial. Such thermometers may sometimes be seen in tront of city stores. A metal thermometer may also be connected with an arm, bearing a pen, which is moved as the temperature changes. This pen may be so placed as to press against a piece of paper on a, cylinder, revolved by clockwork. As the pen rises and falls, while the 2. Barometers. — The weight, or pressure, of air will push liquid up into a tube having a vacuum in the top. It will push the liquid up until a column is formed that equals the weight of the air column pressing on it. It is because of this air pressure that water is pushed up from a well into the tube of a pump. The stroke of the pump exhausts air from the tube, thus tending to make a vacuum, into which the water may be pushed by the air pressure. Since a column of water about 30 feet high balances the air pressure, an ordinary pump could not possibly raise water from a fifty-foot well. Years ago water, in tubes over 30 feet long, was used to measure air pressure. Mercury is now employed' because it is so heavy that a column only thirty inches high balances the air pressure. An instrument containing such a mercury column is called a barometer. Any one can make a rough barometer with a glass tube 35 inches long, sealed at one end. Fill it with mercury, and invert it, with the open end in a sinall dish of mercury, being careful not to allow the mercury to spill. The mercury will fall a few inches, and air pressure will keep it there. By fastening it to a standard to keep it upright, one may watch the mercury rise and fall from day to day. A scale of inches and tenths of inches may be marked on the glass with a piece of quartz or a glazier's diamond ; or on the piece of wood to which the tube is fastened. By comparison with a barometer the scale may be made exact. Ordinary mercury barometers are graduated in inches and tenths of inches, and a scale, called a vernier, enables readings to hundredths of inches. As storms come and go the air pressure varies, and with these changes the height of the mercury column changes. When the air is heavy the barometer column is high, and there is a high barometer ; when the air is light the barometer column is low, and there is a low barometer. For example, 30.1 inches is a high barometer ; 29.3 is a low barometer. Since there is less air (and therefore less pressure) above high lands than lowlands, the barometer is low on highlands and higk on lowlands. As this differ&nce in pressure varies quite regu. larly, a barometer may be used to measure elevation ; for a, cnange of an inch in the mercury column represents a difference in elevation of a certain number of feet. climbed. One serious disadvantage in the use of the aneroid is that it is affected by all changes in air pressure. Thus, if a storm passes while the aneroid is being used to measure an elevation, the change in air pressure causes the hand to move, making an error in the observation. This can be corrected, however, by comparing its readings with those of another barometer kept at a fixed place. As in the case of thermometers, there are self-recording barometers, or barographs. In these, as in thermographs, a pen point pressed against a roll of paper on a cylinder, revolved by clockwork, gives a continuous record of changes in pressure. 3. Anemometers. — Wind direction is determined by the ordinary weather vane, and the rate at which the air is moving by the aneraometer (Fig. 566). The latter instrument consists of four metal cups on crossbars, revolved by the wind striking the hollow side of the cups. Each revolution is communicated the velocity. Wind velocity is measured in miles per hour, and the dial is so graduated that the hand indicates the number of miles the wind has moved. An anemometer may be connected by electric wire to a self-recording apparatus. A slight breeze has a velocity of from 1 to 10 miles per hour ; a strong wind from 20 to 30 miles ; a gale from 40 to 60 miles ; and a tornado wind even as much as 200 miles per hour. 4. Measurement of Vapor. — There are several instruments for determining the humidity of the air. One of these is the hair hygrometer, which consists of a bundle of hair robbed of its oil. 8uch hair will absorb vapor, changing in length as the amount of absorbed vapor varies. It is Since evaporation is more rapid when the air is moving, th( sling psychrometer is whirled around for a minute or two. If tlu air is saturated, there will be no evaporation from the wet muslin, and the two thermometers will, therefore, read the same ; but if the air is dry, the wet bulb thermometer will register a perceptibly lower temperature. The United States Weather Bureau furnishes Various instruments are used for determining the rate of evaporation, which varies from day to day and from place to place. An evaporating pan consists of a dish of water in which is placed a ruler graduated in inches and tenths of inches. By this, one can tell how much is evaporated from the water surface in a given time. Rain should be prevented from falling into the pan, but it should be freely open to the air. It should not be exposed to the sun, because warming increases evaporation. It is best to place it in the ground with the top level with the surface. 5. Rainfall Measurement. — Rainfall is recorded in number of inches and tenths of inches that falls on a given surface. Any cylinder, as a tomato can, could be used as a rain gauge, or measurer ; but an ordinary rainfall is so slight that it would be difficult to measure it unless some provision were made for collecting the water in a smaller space than the surface on which it fell. Any tinsmith can make a rain gauge, with two cylinders, one inside of the other, the inside cylinder having an area of 2.53 inches, the outside one 8 inches (Fig. 561). A funnel fits over the outside cylinder, and a hole in it leads into the inside cylinder. The rain that falls on the funnel collects in the bottom of the inner cylinder to a depth ten times that of the actual rainfall. Measuring this with a ruler, and dividing by ten, gives the actual rainfall, even though it is slight. There are also self-recording rain gauges. Instruments are sometimes used for measuring snowfall ; but usually this can be fairly well done by measuring its depth in some place where it is not drifted. The average snowfall is about ten times the amount that would have fallen as rain. In weather records it is customary to record snowfall in inches of rain. Place snow in a cylinder, filling it to a depth of a foot, and melt it to see how much water it produces. Do not pack the snow down. 6- An Instrument Shelter. — In order to get good results, meteorological instruments must be placed where they are not influenced by local conditions. For example, two thermometers, one in the shade, the other exposed to the sun, will give very different readings. A simple instrument shelter, made of inclined, overlapping slabs, far enough apart to let the air circulate freely, and yet near enough together to keep the sun out, is easily made. It should be placed either on open ground or on the roof. METEOROLOGICAL INSTRUMENTS. The barometer may be kept in the schooh'oom, the rain gauge on open ground away from a building, and the anemometer on the roof ; but the other instruments are best kept in an instrument shelter. Suggestions. — For purchase of meteorological instruments, see p. 438. As indicated above, it is possible to make several of the common instruments, especially the barometer, psychrometer, evaporating pan, and rain gauge. This might easily be done in the manual training department. AVith these instruments daily records may be kept, and laboratory work of value done, especially for comparison with the study of weather maps and storms. Daily and seasonal temperature curves may also be made. If this work is carried along with the study of the atmosphere, the teacher will find many opportunities for connecting observations with facts in the book. For example, observe the humidity of the air near the ground when dew is forming and when it is not. When frost is forming, take the temperature of the ground and of the air 10 feet above it to see if radiation cools the ground. After the barometer begins to fall, does it rain ? What change in wind direction then takes place? In temperature, etc.? The U. S. Weather Bureau issues daily maps showing weather conditions throughout the country. By application these can doubtless be secured for the school, and, being placed in the schoolroom, will serve as a valuable basis for laboratory study. The weather maps are based upon reports telegraphed from Weather Bureau Stations in all sections of the country ; and the facts regarding temperature, rainfall, and wind are placed in a table at the bottom of the map. On the basis of these reports, predictions for the next day are made at a central office. On the map, which is an outline map of United States, the direction of the wind is indicated by arrows. At the ends of some of the arrows is the letter R, meaning rain, or S, meaning snow. Arrows that terminate in blank circles ($) mean clear weather; when crossed by a line (^), partly cloudy; and when occupied by a cross ($), cloudy. The centers of high and low pressure areas are indicated by the words High and Low. Dotted lines (isothermal lines) pass through places having equal temperatures, and continuous lines (isobaric lines) pass through places with equal air pressure. The barometric readings (29.8, 30.1, etc.) are all reduced to sea level ; that is, made to read as they would if the station were at sea level. Thus the weather maps, besides describing the weather conditions and predicting for the next day, contain a large amount of information concerning the weather of different sections. A study of the maps on several successive days will make their meaning plain, and will illustrate many points discussed in the book. Sets of maps suitable for the work suggested below are easily obtained by keeping the maps for a year or two. Out of date sets may possibly be obtained from the Weather Bureau. Or the teacher could make large wall maps for class use, selecting typical sets, and sketching the weather conditions on a large outline map of United States. Suggestions. — (1) Study a weather map to understand its meaning. Which isotherm passes nearest your home? What other places have the same temperature ? What is the air pressure ? What other places are on the same isobar ? Is the weather at your home clear, cloudy, or rainy ? What is the wind direction? How do these facts compare with your WEATHER MAPS. 427 own observations the previous day ? Study the weather maps for the next two days. What differences are noticed? Do you find any explanation ? (2) Select weather maps to illustrate a typical storm. Have each student make a copy of it on a blank map of United States. Have them tell in what parts the pressure is low, and where high. Shade between the isobars. Shade on the map the rainy or snowy sections. With another colored pencil, mark the cloudy areas. What is the direction of the winds in the diiferent areas? What part of the storm area is warmest? What part coolest ? What is the direction of the wind in each case? Can you find an explanation of any of the facts observed? (3) In the same way, study the weather maps for the next three days. Write a statement of the changes that have occurred. On an outline map draw the path followed by the storm center. Select some place on the map, and have the students describe the weather changes — pressure, temperature, wind, and rain — for the four days. (4) In the same way study a set of maps in which a typical high pressure area, or anticyclone, passes across the country. (5) On an outline map plot around the same central point the winds of three well-defined storms. Also three anticyclones. What about their direction ? (6) Give to each student a map with a well-defined storm, and have him tell what he thinks the weather conditions were the day before, and what they were the next day. First remove the predictions from the map. After the predictions have been written down, show the actual maps. This practice may be continued until the class becomes fairly proficient in predictions. Toward the end of these exercises have the students sketch their predictions on outline maps ; that is, upon the basis of their study of a map for a given day, let them make a weather map of the previous and succeeding days. Care should be taken to select well-defined storms that move regularly, otherwise the results maybe poor. (7) Give out problems; many will be suggested by a study of a series of weather maps. For example, given a well-defined low at Chicago, temperature 34.5° : is it clear or rainy ? Is the temperature probably higher or lower at Minneapolis ? At Indianapolis? On a sketch map of United States indicate the area of probable snow. Of rain. What will the weather probably be next day at Chicago? At Cleveland? (8) Upon the basis of observations with instruments in the school make weather predictions. (9) Each day give the weather map to one of the students, and let him report the facts of barometer, temperature, position of highs and lows, etc. ; or, better, sketoh them on an outline map for the class to see. Then call for predictions from the class, and have them give their reasons. Then read the prediction on the map. Next day call for a statement of how nearly correct the prediction was. Various methods are employed to represent the surface of the earth by maps. Among these are relief maps, hachure maps, and contour maps, all of much value in a study of physical geography. 1. Relief Maps or Models. — Ordinary maps are flat ; and the usual political map makes little attempt to represent relief. Yet by shading, or by color, some are made to indicate the general distribution of highlands and lowlands. A far better means of representing a country is by relief map, or model, in which the surface is actually raised to represent irregularities of the land. Owing to the small size of such maps, it is usually necessary to exaggerate the vertical, that is, make the scale of elevation, or vertical scale, different from the horizontal scale. Thus one inch vertically may represent 1000 feet, while in the horizontal scale an inch represents 10,000 or even 20,000 feet. To avoid wrong impressions from the use of such maps, care should be used to understand and make allowance for this exaggeration. The great expense of making relief maps prevents their use in most school laboratories. Figures 22-26, 114, 460, 461, 464, 476, 477, and 485 are photographs of such models. 2. Hachure Maps. — The United States Coast Survey and the surveys of many European countries make use of hachures to represent irregularities of the surface of small sections. A hachure map is one in which the relief is brought out by shading, through the use of lines drawn more or less closely together, and all pointing in the direction of the slope (Fig. 562). Such a map is very graphic, and exceedingly useful in a study of the general form of the land. For some purposes its usefulness is lessened by the fact that, though it clearly brings out differences in elevation between adjoining regions, it does not tell the actual elevations. 3. Contour Maps. — The fact last mentioned has led other surveys, for example the U. S. Geological Survey, to adopt mntour lineSy Qx lines passing through places of equal elevation. MAPS. 429 Imagine a rather irregular beach at low tide when there are no waves. The water marks a contour line, and extends up the depressions, or valleys, in the sand. This may be called the 0 contour ; if the tide rises five feet, a new contour is marked five feet above the other. This might be called the five-foot contour. In making contour maps, sea level is reckoned as 0, and each contour passes through all places on the map that are at the same level above sea; that is, places which, the sea would touch if it rose that high. Every place through which the 100-foot contour passes is just 100 feet above sea level. On such maps, therefore, it is possible to tell the elevation of every place. Contour maps do not express relief so graphically as hachure maps, but, with a little study, one learns to quickly interpret from them the forms of the land. Plains have few contours, far apart ; gorges have many, close together ; rounded hills have contours of different shape from those on steep-sided hills, etc. Figures 78, 82, 121, 131, 137, 145, 192, and 193 are contour maps. On the U. S. Geological Survey maps the horizontal scale is usually about one inch to the mile. The vertical scale, or contour interval, is usually 20 feet ; that is, a contour is drawn for every 20 feet pf elevation. Therefore, the vertical distance, or interval, between two contours is 20 feet. In sparsely settled or mountainous regions a contour interval of 100 feet is often chosen. Suggestions. — (1) Find out if the U. S. Geological Survey (WashingtoD, D.C.) has issued a contour map of your vicinity. If so, get a copy (cost 5 cents), mount it (p. 437), and carry it on your walks or bicycle rides. You will find it of great service. (2) Let the class have practice in making simple contour sketches; for example, have them make contours to show a round hill, a long hill, a hill steep on one end, two hills and a valley, a broad valley, a gorge, etc. Also draw simple contour sketches on the board (for example, a round hill), and have the class make cross sections of them ; that is, sections to show the profile as if the hill were sliced through. Keep the class at this work until they understand how to do quickly what is given. (3) From some model select a section, and have the class sketch a contour map of it. (4) Obtain a series of contour maps, and have the class make cross sections along lines drawn on the map by the teacher. To make these sections, first draw a line on the paper equal in length to the line on the map. Then, for the vertical scale, draw, parallel to this, other lines ^^ inch apart, Let the distance between two of these lines represent 20 feet. Then proceed to draw the profile. (5) After some practice in cross-sectioning, select a series of maps and assign to each student part or all of a map to define the topography in words. This may well be followed by other maps. (0) The teacher may, possibly, deem it worth while to have the class make a map of a small area. With a tape line, an aneroid barometer, a level, and a compass, a rough map may easily be made. (7) If the teacher would each year have a model made by the class, the school would soon accumulate a valuable equipment. It is not very difficult to make a model. For the first one start with a simple region — say the Marion, Iowa, sheet. Find the lowest contour on the sheet and transfer it to tracing paper, then to a thin cardboard sheet the size of the map. Then cut the cardboard along the line. Tack it to a board, or thick cardboard, the size of the map. Do the same for the next highest contour, and tack this to the first. Continue until there is a pile of cardboards, one foj each contour. Divided among many, this is not a very difficult task. With molding wax, smooth the surface so that no cardboard edges appear. After one or two trials a very satisfactory model will be madeOn more complex sheets it is not necessary to trace every contour. An interesting model may be made by starting with a large number of sheets of the same map and, instead of tracing the contours, cut the map itself, and paste sheet on sheet until each contour is represented. To cut the sheets with an even edge, lay the map on a sheet of glass or zinc and cut it with a sharp knife. APPENDIX J, LABORATORY EQUIPMENT. 1. Models. — £:. E. howell (612 17th St., N.AV., Washington, D.C.) has a number of models of great value in laboratory work. He also offers for sale large photographs of these. Catalogue sent on application. G. C. Curtis (64 Crawford St., Boston, Mass.) has a set of three excellent geographical models {glaciers, volcanoes, and seacoast). The Harvard Geographical Models, a set of three, are sold by Ginn & Co., Boston, for ^20 a set. These last two sets should be in every laboratory of physical geography. The Jones model of the earth is very valuable (cost $50, A. H. Andrews & Co., Chicago). For construction of models from topographic maps, see page 430. 2. Maps. — The Kiepert and the Habenicht Sf Si/dow relief maps of continents and parts of Europe are the best maps of this nature. The various government bureaus (see below) will on application send catalogues of their maps, from which the teacher may select those desired. The following lists have been carefully prepared to secure representative maps of various phenomena, and they may serve as the nucleus of a map collection for laboratory use. For further suggestions, see pamphlet by Davis, King, and Collie, I'he Use of Governmental Maps in Schools (Henry Holt & Co., New York, 1894, $0.30) ; also Davis, Journal of Geology, Vol. IV, 1896, p. 484. Foreign maps may be imported through G. E. Stechert (9 East 16th St., New York). The entire United States coast is charted by the U. S. Coast Survey, and many parts of the country are mapped by the U. S. Geological Survey. All of New Jersey, Massachusetts, Connecticut, Rhode Island, and most of New Y'ork are now mapped, as well as portions of each of the other states. The Geological Survey topographic sheets may be ordered for $0.05 each, or at the rate of $0.02 a sheet if 100 or more are ordered. Money must be sent by money order in advance. The Geological Survey also issues special maps, for example a series of different scale maps of United States; also geological folios, — perhaps of your district. Each school should have sets of the United States Geological Survey Physiographic Folios, especially the first two. They contain selected maps, with description, to illustrate physiographic types. Folios 1 and 2 cost $0.25 each ; No. 3, $0.50. 3. Use of Topographic Maps. — The use made of topographic sheets will vary with the teacher, the time available, and the number and variety of sheets at hand. The following is the method adopted by one teacher, who has all the maps he needs, both American and foreign. After the students become familiar with the meaning and use of topographic maps (p. 429), a topic is chosen for a laboratory period, say glacial action, or one phase of it, and typical maps (coijibined sheets) illustrating the phenomena are hung about the room to be studied and interpreted, careful notes being taken. At the close of the period a review quiz is held by the teacher, with the object of correlating observations and bringing out points whose full significance may not have been apparent to the students. The lesson is definitely correlated with the text-book work, and generally covers a topic then being studied. In addition to the wall maps, single sheets are placed in the hands of each student, each sheet clearly illustrating some one phase of the topic chosen. This illustration the student must discover by observation. The study proceeds somewhat as follows : (1) Location : (a) latitude ; (h) longitude ; (c) position on United States contour map ; (d) physiographic relationships (i.e. on coastal plain, in Adirondacks, etc.). (2) General physiography : (a) highest elevation ; (h) lowest section ; (c) direction of rivers ; {d) abundance or scarcity of tributaries ; (e) humid or arid region; (/) form of valleys; (^r) slopes; (h) nature of divides; (i) direction of roads; (y) influence of physiography on roads, railways, and settlement. (3) Spec ijic points (for example, on Elmira, N.Y., sheet); (a) find morainic hills near Lower Pine Valley — the ice front stood there; (b) describe J;he valley south to Elmira and southwest to East Corning ; (c) measure its width and compare with that occupied by the Chemung River west of Elmira; (d) what is a wash plain (see textbook) ? (e) could this be a wash plain ? If so, what change has it caused in the depth of the valley? Would it account for the broad, flatbottomed valley followed by the railroad? Might it have raised the valley bottom so high that the Chemung could not follow its former course via Ilorseheads ? This is what has happened. The subject can be developed formally by mimeographing questions, or putting them on the blackboard; or, better, if the class is not too large, by giving general directions, then asking specific questions, either of the class as a whole or of individuals. Work done on individual sheets is included in the review at the end of the exercise. By the above method, when plains are studied laboratory exercises may accompany the recitation work ; the same with shore lines, lakes, mountains, etc. The student should not be allowed to be diverted by other phenomena than those directly beaming on the topic. The same LABORATORY EQUIPMENT. 433 map may often be used in several periods to illustrate different phenomena. In this work the student is expected to look for comparisons and contrasts; for example, under "Plains," compare and contrast the the Fargo, N.D., Kaibab, Ariz., and Palmyra, N.Y., sheets. Another method used is to stady a sheet to detect all phenomena represented ; but this lacks many of the advantages of a study by topics. In the absence of a regular laboratory manual, it is necessary for teachers to develop their own methods, and this Appendix is merely a hint as to one direction in which this may be done. It calls for sacrifice of time and energy on the part of the teacher ; but all who are willing to make this sacrifice will be abundantly repaid by the improved work and greater interest of the class. Even if formal laboratory work is not given, the maps are of great use as illustrations of the text. 4. One Hundred Selected Sheets, United States Geological Survey, Topographic Map. — These maps should be purchased by the hundred (-12 a hundred) ; and it is desirable to provide enough sets for each student in the laboratory to have a copy of each, or', at least, to provide one for every two students. They should be mounted (p. 437). (1) Glassboro, N.J. ; (2) Leonardtown, Md. ; (3) Pt. Lookout, ALL; (4) Fargo, N.D.; (5) Hamlin, N.Y.; (6) Marion, Iowa: (7) Wichita, Kan.; (8) Butler, Mo.; (9) Marshall, Ark.; (10) Lamar, Colo.; (liyBrowmvood, Tex.; (12) Coleman, Tex.; (13) Higbee, Colo.; (14) Kaibab, Ariz.: (15) Watrous, N.M.; (16) Boise, Idaho; (17) Modoc Lava Bed, Cal. ; (18) Elmira, N.Y.; (19) Kaaterskill, N.Y.; (20) Gaines, Pa.; (21) Briceville, Tenn. ; (22) Scottsboro, Ala.; (23) Salyersville, Ky.; (24) Huntington, W.Va. ; (25) Pikeville, Tenn.; (26) Bisuka, Idaho; (27) Great Falls, Mont.; (28) St. Paul, Mitm. ; (29) Palo Pinto, Tex.; (30) Delaware Water Gap, Pa.; (31) West Point, N.Y.; (32) Jefferson City, Mo. ; (33) Junction City, Kan. ; (34) Kearney, Neb.; (35) Lexington, Neb.; (36) Donaldsonville, La.; (37) Point a la Hache, La.; (38) Cohoes, N.Y.; (39) Springfield, Mass.; (40) Alturas, Cal.; (41) Pikes Peak, Colo.; (42) Telluride, Colo.; (43) Platte Canyon, Colo.; (44) Huerfano Park, Colo.; (45) Livingston, Mont.; (46) Mt. Washington, N.H.; (47) Becket, Mass.; (48) Monadnock, N.H.; (49) Hartford, Conn.; (50) Mt. Marcy, N.Y.; (51) Monterey, Va.; (52) Fort Payne, Ala.; (53) Estillville, Ky.; (54) Franklin, W.Va.; (55) Maynardville, Tenn.; (56) Hazleton, Pa.; (57) Lykens, Pa.; (58) Atlanta, Ga. ; (59) Lassen Peak, Cal; (60) Shasta, Cal.; (61) Mt. Taylor, N.M.; (62) Marysville, Cal.; (63) Ashland, Ore.; (64) Henry Mountains, Utah; (65) Sierraville, Cal.; (66) Disaster, Nev. ; (67) Paradise, Nev.; (68) Granite Range, Nev.; (69) Tooele Valley, Utah; (70) Salt Lake, Utah; (71) Boothbay, Me.; (72) Coos Bay, Ore.; (73) Seattle, Wash.; (74) San Francisco, Cat. ; (75) New Haven, Conn.; (76) Brookli/n, N.Y.; (77) Charlestown, R.I.; (78) New London, Conn.; (79) Duluth, Minn.; (80) Pulaski, NY. ; (81) Marthas Vineyard, Mass.; (82) Atlantic City, N.J.; (83) Barnegat, N.J.; (84) Sandy Hook, N.J.; (85) Boston Bay, Mass.; (86) Mt. Lyell, Cal.; (87) Minneapolis, Minn.; (88) Plymouth, Mass.; (89) Stonington, Conn.; (90) Bal'/winsi'ille,N.Y.; (91) Newcomb, NY. ; (92) Elizabethtown, NY. ; (93) Plaltsburg, NY.; (94) Skaneateles, NY.; (95) Ot'iW, iV^.F.; (96) iacon, //^.; (97) Ottawa, III.; (98) Watertown, Wis.; (99) TFee^/sj9or?, iV.F.; (100) Os?oe^o, iV.F. The following must be ordered as Special Sheets: (A) Norfolk Special, $0.10; (B) New York City and Vicinity Special, $0.25; (C) Rochester Special, ^O.IO ; (D) Niagara River and Vicinity Special, $0.10; (E) St. Louis and Vicinity Special, $0.10 ; (F) Crater Lake Special, $0.05. features illustrated on the above maps. The teacher will find others. Coastal Plain, 1-3, 82, 83, A; Lake Plains (West), 59, 65-70; Lake Plains (Lake Agassiz), 4; Lake Plains (Ontario), 5, C, D ; Lava Plains (Plateaus, West), 16, 17, 26, 61; Central Plains, 6, 8, 32, 96, 97; Great Plains (more or less dissected), 7, 10, 12, 27, 29, 33, 35; Dissected Arid Plateau, 13, 14, 15, 61; Escarpments, 14, D; Mesas, 11, 13, 14, 15, 61; Buttes, 12, 13, 26; Desert, 66-70; Desert Sand Dunes, 66, 67; Dissected Moist Plateaus, 9, 18, 23, 25, 94, 95; Catskills, 19 ; Immature Drainage, 1, 83, A ; Post-glacial Young Streams, 28, 38, 94, 95, 96, C, D ; Young Valleys, 9, 13, 26, 27," 49; Waterfalls, 27, C, D; Canyons, 13, 14, 16, 20; Mountain Gorges, 43, 45; Water Gaps, 30, 31, 51, 52, 57; Mature Valleys, 18-24, 38, 39, 47-58, 75, 94, 95; Arid Land Drainage, 13-16, 40, 65-70; Alluvial Fans, 45, 65 ; River-made Plains, 60, 62 ; Braided Course, 34, 35, 66 ; Floodplains, 8, 9, 32, 34, 35, 87, 96, 97, E ; Bluffs, 32, 35, E ; Levee, 36 ; Crevasse, 36 ; Oleanders, 8, 32, 33, 52, 53, 55, E ; Intrenched Meanders, 23, 29 ; Delta, 93 ; Terraces, 38, 39, 49, 96 ; Erie Canal, 99 ; Irrigation, 10, 70 ; Basin Ranges, 40; Coast Ranges, 60, 72, 74; Sierra Nevada, 65; Rocky Mountai?is, 4:1-45; Appalachians, 2\, 25, 30, 51-57; Adlrondacks, 50, 91, 92 ; New England Mountains, 46-49, 75, 77 ; Piedmont, 58 ; Young Mountains, 40-45, 60, 65,72, 74; Mountains (early maturity), 46 ; Mature Mountains, 30, 31,39, 47, 57, 71, 75, 77, 78, 89, 91-93 ; Mountain Ridges, 51-57 ; Old Mountains, 58, 85 ; Peneplain, 58 ; Monadnocks, 48, 58 ; Volcanoes^ 5962, F ; Laccolites, 64 ; Trap Ridges, 39, 75 ; Palisades, B ; Glaciers, 60 ; Cirques, 86; Moraines, 76, 77, 81, 87-89 ; Wash Plains, 18, 76, 77, 81 ; iMoraine Kettles, 88; Karnes (Pinnacle Hills), C; Drumlins, 49, 85, 90, 98-100; Glacial Lake Overflow Channels, 90, 96, 97, 99 ; Lake on Coastal Plain, A ; Delta Lakes, 37 ; Ox-bow Lakes, 8, 33, E ; Volcanic LakeSy 59 ; Crater Lakes, 59, 63, F; Glacial Lakes and Swamps, 31, 45, 47, 48, 50, 77, 78, 85-94, 98^ 100; Lake Champlain, 93; Finger Lakes, 94, 95; Coastal Plain Swamps, 1, A; River Swamps, 1, 62, 87, 96, A; Delta Swa7nps, 36, 37; Lake Swamps, 80, 93, 100, C ; Alkali Flats and Plat/as, 65, 66, 68; Drowned Coastal Plain, 2, 3, 83, 84, A; Drowned Coast, 71-78, 81, 85, 89, B; Drowned Lake Coast, 79, 80, 93, 100, C ; Harbors, 73-75, 78, 79, A, B; Wave-cut Cliffs, 84, 100; Wave-cut Islands, ^^; Beaches, 72; Tied Islands, So; Bars, shutting in Bays, 77, 79-81, 85, 100, C; Sa?id Bars, 76, 78, 81, 88, 89; Hooks, 84; Sand Dunes, 72, 83, 84; Offshore Bars, inclosing Lagoons, 8284, A ; Salt Marshes, 74-76, 78, 82, 85, 89, A, B. 5. Thirty -five Grouped Sheets. — The following groups of sheets a '« selected for mounting to make large maps (see directions below). Each group illustrates well at least one phenomenon, and a number illustrate several. In addition, they all contain many important details worthy of study. It would also be desirable to secure and mount in a large map all the sheets in the vicinity of the home region. Nearly all of these sheets could be used singly if mounting in groups seems too difficult. 1. Colorado River and Vicinity — illustrating plateaus, mesas, buttes, canyons, volcanoes, arid drainage, the following sheets : (Pioche, St. George, Kanah, Escalante, Henry Mountains, Utah, Marsh Pass, Echo Cliffs, Kaibah, Mt. Trumbull, St. 2'homas, Camp Mohave, Diamond Creek, Chino, San Francisco Mt., Tusayan, Ariz.). 2. Overburdened Platte River — also great plains (^Kearney, Wood River, Grand Island, Neb.). 3. Same — (Minden, Kenesaw, Neb,). 4. Connecticut Valley — bordering upland, lowland, trap ridges, terraces, ox-bow lake {Cireenfield, Warwick, Northampton, Bel'chertown, Springfeld, Palmer, Mass.). 5. River Floodplain and Meanders — also great plains {Kansas City, Oskaloosa, Olathe, Lawrence, Kan.). 6. Mississippi Delta (West Delta, East Delta, La.). T Mississippi Delta and Floodplain — also location of New Orleans (Boro,cCt Carre, Spanish Fort, Chef Menteur, Rigolets, Toulme, Bodreau, Shell Beach, St. Bernard, New Orleans, Hahnville, La For' tuna, Deine, Point a la Hach'', Barataria, Cut Off, Forts, Quarantine, Ft. Livingston, Creole, Lake Felicity, La.). 8. Alluvial Fans — arid region {Pomona, Cucamonga, San Bernardino, Cal.). 9. , Coastal Plain — also shore lines, bars, marsh, etc. {Boi-deniown, Cassville, Asbury Park, Pemberton, Whiting, Barnegat, N.J.). 10. Coastal Plain — drowned, swampy {Prince Frederick, Brandywine, Wicomico, Leonardtoicn, Md.). 11. Coastal Plain — young drainage, lakes, and swamps {WiUiston, Citra, Dunnellon, Ocala Isala, Aparka, Pana Soffkee, Fla.). 12. Lake Plain — bed of Lake Agassiz {Fargo, Casselton, N.D.). 13. Great Plains {Wichita, Cheney, Kingman, Wellington, Caldwell, Anthony, Kan.). 14. Maturely Dissected Plateau {Salyersville, Prestonsburg, Hazard^ Whiteshurg, Ky.). 15. Same (Huntington, Charleston, Kanawha FaUs, Warjiehl, Oceana, Raleigh, W.Va.)- 16. Mature Mountains and Plateau (Chattanooga, Sewanee, Ringgols, Stevenson, Tenn.) . 17. Dissected Arid Land Plateau — canyons, mesas, buttes, etc. {Higbee, Timpas, Apishapa, Mt. Carrizo, Mesa de Maya, El Moro, Colo.). 18. Mesas. Buttes, Volcanoes, Arid Drainage (Wingate, Mt. Taylor, N.M.). 20. Southern Appalacheans (Greenville, Roan Mt., Ashville, Mt. Mitchell, N.C). 21. Southern Appalachians (Staunton, Monterey, HuntersvillCf Lexington, Natural Bridge, Lewishurg, Va., W.Va.). 22. Mountain Ridges — river meanders, Shenandoah valley (Harper's Ferry, Winchester, Romney, Warrenton, Luray, Woodstock, Va.). 2.3. New England Mountains— even-topped upland, Monadnock (Peterhoro, Monadnock, Keene, N.H., Fitchhurg, Winchendon, Warwick, Mass.). 24. Adirondack^ — part of Lake Champlain, glacial lakes (Lake Placid, Ausahle, Willshoto, Mt. Marcy, Elizahethtown, Port Henry, Schroon Lake, Paradox ^ ake, Ticonderoga, N.Y.). 2.5. Appalachians and Virginia PiedmoinT (Goochland, Palmyra, Buckingham, Amelia, Farmville, Appomattox, Va.). 26. Piedmont and Coastal Plain — location of Philadelphia (Germantown, Norristown, Chester, Philadelphia, Pa.). 27. Drumlins — glacial lakes, cities on river with rapids due to glacial action, also beaches and salt marshes (Haverhill, Newhuryport, Lawrence, Salem, Mass.). 28. Finger Lakes — mature plateau, post-glacial gorges, lake deltas (Geneva, Auburn, Skaneateles, Ovid, Genoa, Moravia, Watkins, Ithaca, Dryden, N.Y.). 29. Drumlins — drainage interfered with by drift, overflow channels, lake shores (Oswego, Sodus Bay, Pultneyville, Weedsport, Clyde, Palmyra, Auburn, Geneva, Phelps, N.Y.). 30. Drumlins — glacial lakes and swamps' (il/arfjson, 5wn Prairie, Waterloo, Watertown, Evansville, Stoughton, Koshkonong, Whitewater, Wis.). 31. Drowned Coast (Gardiner, Wiscasset, Boothbay, Bath, Me.). 32. Same (Boothbay, Bath, Freeport, Gray, Small Point, Casco Bay, Portland, Me.). 33. Bays, — bars, wave-cut cliffs, moraine, wash plain (Marthas Vineyard, Gay Head, Mass.). 34. Cape Cod — bars, wave-cut cliffs, sand dunes, moraine, morainic lakes (Provincetown, Welljieet, Chatham, Yarmouth, Barnstable, Mass.). 35. Yellowstone Park (Gallatin, Canyon, Lake, Shoshone, Wy.). 6. Thirty Selected Sheets, United States Coast Survey, illustrating Typical Coast Lines.— (Washington, D.C. \|0.50 each; catalogue free; order by number.) 0 General Chart, coast of Maine and Massachusetts)', 103, 104, 105, 106 (Maine coast, more detailed) ; 108 (Coast from southern Maine to Cape Ann) ; 109 (Boston Bay) ; 8 (Approaches to New York, Gay Head to Cape Henlopen) ; 113 (Narragansett Bay) ; 52 (Montauk Point ^o New York, with Long Island Sound) ; 119 (^Southern shore of Long Island) ; 121, 122, 123 (New Jersey coast, Sandy Hook to Cape May) ; 370 {Delaware and Chesapeake bays) ; 11 (Cape Hatteras to Cape Romain) ; 142 (Cape Hatteras) ; 147 (Cape Lookout) ; 15 (Straits of Florida, Coral Reefs) ; 170 (Key West and Vicinity, Coral Reefs) ; 1007 (General Chart, Gulf of Mexico) ; 188 (Mobile Bay) ; 19 (Mississipjn Delta and vicinity) ; 194 (Mississippi Delta) ; 21 (Galveston to the Rio Grande) ; 212 (Bar from Rio Grande northward)', 5400, 5500 (California coast); 3089, 8100 (Drowned ^^.askan coast). 7. River and Lake Maps. — The Mississippi River Commission (St. Louis), and the Missouri River Commission (St. Louis) issue charts of these rivers, of which the following are especially useful. Alap of Alluvial Valley of Mississippi, 8 sheets ($1 per set) ; Upper Mississippi, 4 sheets ($0.70 per set) ; Mississippi, Charts 8, 22, 35, 36, 38, 39, 52 of the map on scale of 1 : 20,000, showing meanders, oxbows, etc. ($0.26 per sheet). If the school is located on the river, the sheets of that vicinity should be secured. Charts of the Great Lakes (United States Engineer's Office, Detroit, Mich.) illustrate many shore-line phenomena. Nos. 1, 5, 6; also Lake Ontario, Niagara River, Lake Erie, and Lake St. Clair are especially valuable. If the school is on the lakes, much use should be made of the lake charts, especially those near by. 8. Mounting Maps. — It is real economy to have all maps backed with cloth. This will be done by many bookbinders, or it can be done in the dchool, using a thin, bleached, white cotton cloth of ordinary width for «iingle sheets ; extra width for grouped sheets. Use ordinary flour paste, which costs very little if purchased from a paper hanger. For successnil map mounting have a smooth surface (a large drawing board or table top) on which to tack the cloth. Stretch the cloth and tack it firmly on all sides, then thoroughly wet it. Apply paste to the back of the map and allow it to lie until thoroughly limp, then put it on the cloth, which must not be too wet. Carefully press the map to the cloth with a piece of clean cloth or a photographic roller. Leave until thoroughly dry (at least 24 hours). Combined sheets must first be trimmed, leaving on alternate sheets a, margin of ^ inch for adjoining sheets to overlap. For trimming, to secur ^, an even cut, place the map on a sheet of zinc (tacked to a board), an%i, with a sharp knife, cut along a metal straightedge placed on the map. If a map is not complete, blank spaces may be filled with white paper. Large maps should be rolled, and a wood turner will supply rolk^-s at small cost ; also strips for the top of the map. Curtain rings -nay be screwed into the wooden strip for hanging the map, which, for class use, may be hung to brass rods (\| inch in diameter) along tlw? uides of the may be used. Single sheets are best kept in a case of shallow drawers, using care not to put too many in a drawer, for they are then difficult to handle. Rolled maps are best preserved when kept in a case with shallow partitions, allowing the rolled map to lie horizontally. A cabinet-maker will build a combnied case for rolled and flat maps. 9. Minerals and Rocks, —j^. E. Howell, 612 17th St., N.W., Washington, and Ward's Natural Science Establishment, Rochester, N.Y., offer cheap sets of minerals and rocks suitable for laboratory use in connection with Tarr's Geology or Physical Geography. G. B. Frazer, West Medford, Mass., is another reliable dealer. 10. Meteorological Maps, etc. — Application should be made to have the weather map sent regularly to the school ; and duplicates of out of date maps may possibly be secured on application. Meteorological instruments (see p. 420) may be purchased of J. P. Friez, Baltimore, Md., or //. J. Green, Brooklyn, N.Y. 11. Lantern Slides. — Various firms now supply lanterns for schools, the most satisfactory being electric lanterns. A set of lantern slides, selected by Prof. W. M. Davis, is sold by E. E. Howell (address above) ; T. H. McAllister (49 Nassau St., New York) has a series of geographical slides, and H. W. Fairbanks (Berkeley, Cal.) has a set of western slides for sale. The Geography Supply Bureau (Ithaca, N.Y.) has a selected set of about a thousand of Professor Tarr's best negatives from which slides will be made on order. These slides were selected with the advice and assistance of Professor Tarr, and with special reference to their adapta^ tion to use in schools. The set includes practically all the phenomena of Physical Geography. A printed catalogue, with description of each slide and suggestions, and outline questions for its use, will be sent on application. APPENDIX K. FIELD WORK. The value of field work is such that every course in physical geography ought to be accompanied by at least some. No laboratory or text-book work can take the place of well-conducted field work ; it is worth undertaking even if Saturday is the only time available for it. But a progressive school should provide regular periods for out-of-door v/ork. Directions for field work of sufficient explicitness to be useful as a guide cannot be given without taking up far more space than is available in this book. What kind of work to give is a question which can be settled only by local conditions ; therefore the teacher must develop his own outline. There is no region without some good physiographic phenomena within easy reach. Properly to make use of these field opportunities demands personal knowledge of methods on the part of the teacher. There are, of course, many teachers of physical geography who have not had the training necessary for this work ; for even the universities have been giving regularly organized field courses only in the past few years. Most summer schools in large universities offer instruction in this direction, and any teacher who desires to give field work, but lacks the necessary training, can secure it easily and at slight expense. Knowing how field work is conducted in one region, any real teacher can adapt the same methods to his own needs. It is by the introduction of laboratory work, indoors and out, that physical geography is gaining for itself a rank which is placing it on a par with other science courses in the secondary school curriculum. Ten years ago scarcely a secondary school in the country, and very few normal schools and universities, gave organized laboratory and field work in physical geography. Now many of the better secondary schools provide for it and have specially equipped laboratories. The normal school or university course that does not include such work is now considered weak and unsatisfactory. If the next ten years witnesses an advance equal to that of the last ten, the same will be true of physical geography in the secondary schools. A course in chemistry and physics that is solely a text-book course is now considered ridiculous ; the same should be true of physical geography. The fact that it is likely to be so considered within ten years should spur on every teacher of the subject to the effort to prepare himself for the work and provide for it. The task is not a great one, and the reward is well worth the effort. The following are some of the phenomena that are likely to be found within easy reach of a school. (1) Illustrations of weathering: cliffs, ledges, bowlders, old stone or brick buildings. (2) Nature of country rock: in river valleys, railway cuts, quarries. In such places stratification, joint planes, folding and faulting, and fossils may possibly be found. (3) The soil : for characteristics and depth, look in cuts, as in (2). Is it a soil of rock decay or transported? If the former, study its origin in the cut. If the latter, how transported? (4) River transport tation : road gutters, plowed fields, small wet-weather streams, — nature of work, load carried, disposition of load, result of removal. Fine examples of young stream valleys, alluvial fans, deltas, and waterfalls (over pebbles) are very often found in a road, field, or railway cut. (5) River loork and valley formation : source of water ; variation in volume; sediment load; variation; source of sediment; temporary disposal of it, — on stream bed, in bars, in floodplains, etc. ; place of final deposit of sediment ; effect of removal of sediment on valley form. The entire subject of river work and life history of valleys may be built up around one or two field excursions to a near-by stream. It is not necessary to have grand waterfalls or broad floodplains. A meadow brook has its full lesson. (6) Shore lines : a lake shore or the sea shore ; even a river bank or the shore of a pond may serve. What are the waves doing ? What work have they accomplished ? Why are the pebbles round ? Where has the ground-off material gone? What is the source of the pebbles or sand ? Which way are they moving ? Are there bars, wave-cut cliffs, small stream deltas, shore swamps? Perhaps there are all, possibly only one; in the latter case study that, even though it may seem very insignificant. (7) Glacial phenomena : strife; till banks, — in railway or other cuts ; nature of material ; scratched stones, etc. Are the pebbles or bowlders foreign, i.e. unlike the country rock? Is the till unstratified? Why? Find cuts of stratified drift — evidence of water action. There may be moraines, kames, eskers, or drumlins. Besides these there may be plains, or moiu^^aias, or plateaus, or volcanic phenomena. If so, so much the better -• buvi profitable field work does not necessarily demand grand features. It will be well to have most of the excursions devoted to details and the study of principles : hence a seemingly small illustration may be of the very highest value. At the same time, the field work should not entirely ignore the broad, general features. A very profitable excursion may be conducted in a high tower, or on a high hill overlooking the surrounding country. Field excursions should be made for the purpose of showing the relationship between physiographic phenomena and human interests. They may often be combined with the other excursion suggested above. For example, an excursion might well consider the reason for the location and the nature of work in a quarry ; the location and the difficulties in the way of laying a railway, i.e. the cuts, tunnels, etc.. necessary ; the differences in the soil and their relation to plant life, and especially to crops ; the location of mills, etc. Here again the broad influences of physiographic conditions should not be overlooked. B^^ A\ means, the field work should show clearly the significance of the li^c^Mon andld'?^"^<)pment of the home town and its industries. APPENDIX L. REFERENCE BOOKS. The reference books listed at the end of each chapter deal hi part, if not entirely, with the topic treated in that chapter. There are a number of general books, some of which are included in those lists, which should be in every physical geography laboratory. Among these are most of the following: — Mill, International Geography, Appleton & Co., N.Y., 1902, $3.50; Huxley, P/ujsiographij, Macmillan Co., N. Y., 1891, .\|1.80 ; Geikie, Scenery of Scotland, Macmillan Co., N. Y., 1901, $3.25 ; Tarr, Physical Geography of New York State, Macmillan Co., N.Y., 1902, $3.50; Lubbock (Lord Avebury), Scenery of England, Macmillan Co., N. Y., 1902, $2.50 ; National Geographic Monographs, Physiography of the United States, American Book Co., X.Y., 1895, $2.50; Shaler, Outline of the Earth^s History, Appleton & Co., N. Y., 1898, $1.75; Shaler, Aspects of the Earth, Scribner's Sons, N.Y., 1890, $2.50; Geikie, Fragments of Earth Lore, John Bartholomew, Edinburgh, 1893, 12s. Qd. ; Bonney, Story of Our Planet, Cassell, London, 1898, 7s. M. ; Geikie, Earth Sculpture, Putnam's Sons, N.Y., 1898, $2.00 ; Marr, The Scientific Study of Scenery, Methuen & Co., London, 1900, 6s.; Salisbury, Physical Geography of New Jersey, Vol. IV, Final Report, New Jersey Geological Survey, Trenton, 1902 ; Dryer, Studies in Indiana Geography. Inland Printing Co., Terre Haute, Ind., 1897, $1.25; Powell, Geology of the Uintah Mountains, Department of the Interior, Washington, 1876 (out of print) ; Gilbert, Geology of the Henry Mountains, Department of the Interior, Washington, 1877 (out of print). The following are leading magazines of geography, at least one of which it is desirable to have in the school : Journal of Geography, Chicago, 111., $1.50 ; National Geographic Magazine, Washington, D.C., $2.50 ; Bulletin of the American Geographical Society, New York, $4.00 ; Geographical Journal, London, $6.00; Scottish Geographical Magazine, Edinburgh, $5.00. The United States Geological Survey publishes Bulletins, Annual Reports, Professional Papers, Monographs, Folios, and Irrigation Papers, many of which contain valuable physiographic material, possibly relating to your own region. Aggrading, 53. Agriculture, Central Plains, 311 ; development of, 370; New England, 299; New York, 302; Piedmont Belt, 307; western United States, 315. Air, 13, 18, 19, 229-250 ; effect of gravity on, 231; importance of, 14; importance of, to animals, 353; importance of, to plants, 336; influence of, in weathering, 40; in ocean water, 180; pressure of, 255; warming of, 238. Aneroid barometer, 422. Animals, aid of, in spread of plants, 345, 346 ; aid of, in weathering, 41 ; barriers to spread of, 361 ; dependence of, on plants, 353 ; distribution of, 353366; domestic, 365,371; fresh water, 358 ; homes of, 359 ; in Arctic, 354 ; in Australia, 362; influence in plant variation, 347 ; influence of man on, 364; influence of surroundings on, 353; in South America, 363; in temperate zone, 356; in tropical zone, 357 ; mode of life of, 354 ; of desert, 357 ; on islands, 361 ; spread of, 360 ; zones of, 364. Chasms, 211. Chemically formed rocks, 409, 410. Chesapeake Bay, 24, 74, 209, 306, 329. Chicago, 31, 150, 151, 166, 220, 313, 376. China Sea, 207. Cliffs, sea, 211. Climate, 275-295; Arctic, 293, 294; belt of calms, 279; continental, 288; east coasts, 288; equable, 238; Indian, 284; influence of altitude on, 276; influence of lakes on, 165, 166; influence of ocean currents on, 278; influence of, on plants, 339; influence of topography on, 279; influence • of water on, 277; influence of winds on, 278; mountain, 95; plateau, 83; south temperate zone, 293; southwestern United States, 316 ; temperate zones, 285-293; west coasts, 286. Coast lines, 203-225; changes in, 204; of drowned lands, 208; elevated sea bottom, 205; influence on man, 389; irregularities of, 23-26; irregular mountainous, 207 ; life history of, 221 ; New England, 299; sinking of, 74; straight mountainous, 206. Desert flora, 342. Deserts, 86-89; as barriers to spread of animals, 361 ; as barriers to spread of plants, 346; drainage of, 86; life on, 88; man in, 386; nature of, 86; rainfall of, 86; trade wind, 281; wind work in, 87. Early man, 369. Earth, age of, 45; as a planet, 1-10; contraction of, 18, 35, 99 ; differences in temperature on, 239; general features of, 13-28 ; interior of, 17 ; proof of roundness, 2; radiation from, 235; rotation of, 6 ; shape of, 1 ; size of, 3 ; solid, 16; wind systems of, 258. Fauna, 354: Australian, 362; of Arctic, 354 : of desert, 357 ; fresh-water, 358 ; island, 361; of northern continents, 363; South American, 363; temperate, 356; tropical, 357. Floods, Mississippi, 328. Flora, 339: Alpine, 344; Arctic, 340; of deserts, 342; of mountains, 343; of savannas, 342; of steppes, 342; subtropical, 342; temperate, 340; tropi- Glaciers, 137-150; Alaskan, 139; distribution of valley, 141 ; effects of continental on Mississippi system, 327; effect of continental in New England, 299; effect of continental in Central Plains, 310; former extension of valley, 141 ; Greenland, 143 ; intiuence of continental on New York, 301; valley, 137-142. Lake plains, 78. Lakes, 160-167 ; as resorts, 165; freezing of, 165, 166; glacial, 156; ice-dammed, 149 ; importance of, 165 ; influence on climate, 165, 166; influence on navigation, 166; life history of, 164; oxbow, 63, 328; salt, 163; shores of, 220 ; size and form of, 161 ; storage of water in, 167. Mammoth Cave, 59. Man, aid of, in spreading plants, 345; in Arctic, 384 ; barriers overcome by, 381 ; dependence of, on nature, 369 ; in desert, 386; domestication of animals by, 365 ; early, 369 ; effect in forming lakes, 161 ; effect of ice sheet on, 154156; effects of ocean currents on, 193, 194 ; effects of tides on, 189; eft'ect of valley form on, 58; food of, 370 ; importance of shore lines to, 203; influence of coast line on, 389; influence of continent form on, 26; influence of deltas on, 65; influence of deserts on, 88; influence of lakes on, 165, 167 ; influence of mountains on, 105-109, 388; influence of ocean on, 15, 28; influence of swamps on, 170; influence on animals, 364 ; influence on nature, 379 ; influence on plant variation, 348; in temperate zone, 385; in tropical zone, 385 ; plants of value to, 348 ; relation of plateaus to, 84, 85 ; relation of, to land, 31 ; relation of volcanoes to, 129 ; spread of, 381. Mirage, 232. Mississippi, delta of, 65, 328; drainage area of, 320 ; river, 310, 312 ; rock load of, 52 ; system, 325-328 ; valley of, 76, 77, 310, 325, 328. Mountains, 93-109; Appalachians, .308; as barriers, 106, 308; as barriers to spread of animals, ;^1 ; as barriers to spread of plants, 346; cause of, 99; climate of, 95; crossing of, 106; denudation of, 96; distribution of, 98; drainage of, 103; effect of, on climate, 286, 287; height of, 20; influence on man, 388 ; life history of, 101 ; mineral wealth of, 108 ; names applied to parts of, 94; relation of continents to, 22; resemblance to plateaus, 98 ; rocks of, 93; settlement of, 105; as summer resorts, 107 ; as timber reserves, 107 ; types of, 100. Dcean basins, 175. Ocean bottom, 173-179; deposits on, 176; life on, 197; light on, 182; temperature of, 183, 184; topography of, 178. )ceans, 14, 173-198; as barriers to spread of animals, 361 ; as barriers to spread of plants, 346; depth of, 14, 20, 174, 175, 176; ice in, 194; importance of, 15; life in, 195-198; temperature of, 182-184 ; form of, 26. Plant food, 40. Plants, aid in weathering, 40; Arctic, 340; barriers to spread of, 345; conditions influencing, 336-339; dependence on, of animals, 353; of deserts, 342; distribution of, 336-350; effect of gravity on, 338; importance of air to, 336; importance of soil to, 338 ; importance of sunlight to, 337 ; importance of "water to, 337 ; influ^ce of climate on, 339; means of distribution of, 345; of mountains, 343; relation of, to temperature, 336; of savannas, 342; of steppes, 342; temperate, 340; tropical, 342; of value to man, 348 ; variation in, 346 ; water, 344. Plateaus, 80-85 ; Alleghany, 308-310, 327 ; Appalachian, 308-310; climate of, 83; Colorado, 322, 324; inhabitants of, 84, 85; lava, 81; nature of, 80; New York, 302; relation to continents, 22; resemblance to mountains, 98; sculpturing of, 81. Raindrops, 249. Rainfall, at base of Himalayas, 284; belt of calms, 280; influence of cyclones and anticyclones on, 266; measurement of, 424; of deserts, 86, 282; of temperate zones, 285; of trade-wind belts, 280, 281; of west coasts, 286; on mountains, 96. River pirate, 104. Rivers, aid of, in spreading plants, 345 ; effect of ice on, 53; effect of glacial ice on, 156 ; erosive work of, 52 ; floodplains of, 61; grade of, 56; mature valleys of, 57; mountain, 103; old valleys of, 58; rejuvenated, 83; rock load of, 51 ; superimposed, 83 ; supply of water, 50; of United States, 320-334 ; variation in volume of, 50. Rock flour, 139. Rocks, 408-413 ; chemically formed, 409, 410 ; classification of, 408 ; clastic, 409, 410; fragmental, 40J), 410; igneous, 408, 411, 412; metamorphic, 408, 413; Minerals in, 408; mountain, 93, 94; of crust, 32; organic, 410; resistance of, 34; sedimentary, 408-410; sedimentary, consolidation of, 33. States, 291. Sun, 3,9, 10; apparent movements of, 397; distance to, 5 ; effect of position on temperature, 239; heat from, 10. on, 240 ; effect of, on animals, 353 ; importance of, to plants, 33<) ; influence of cyclones and anticyclones on, 265; measurement of, 420; of ocean, 182; seasonal range in, 243; in temperate zones, 285. Ungava Bay, tides of, 187. United States, physiography of, 298317 ; reasons for development of, 390392; rivers of, 320-3;i4; western, 314. Volcanic plug, 126. Volcanoes, 101, 112-130; cause of, 125; distribution of, 123 ; importance of, 129; in sea, denudation of, 129; life history of, 128; materials erupted from, 122. Wash plains, 149. Water, 18, 19; forms of , 244-250; influence of, on climate, 277 ; need of, by plants, 337; underground, 19, 39, 50, 59; warming of, 238. Weather, 275-295; desert, 282; eastern United States, summer, 291; winter, 292 ; influence of cyclones and anticyclones on, 265; southern ocean, 293; vane, 420. Weathering, 38-44; agents of, 38; aid of organisms in, 40; results of, 42; influence of underground water, 39; rate of, 41. Wind gaps, 104. Winds, 255-262; aid of, in distribution of animals, 3()0, 362 ; aid of, in spread- i ing plants, 345, 346; as barriers to spread of plants, 346; cyclonic storm, 289; influence of, on climate, 278; Influence of cyclones and anticyclones on,t265; measurement of, 422, 423; monsoon, 256-258; prevailing westerly, 260; relation to air pressure 255; trade, 259; variable, prevailing, westerly belt, 289.	177,626	common-pile/pre_1929_books_filtered	newphysicalgeogr00tarrrich	public_library	public_library_1929_dolma-0001.json.gz:3414	https://archive.org/download/newphysicalgeogr00tarrrich/newphysicalgeogr00tarrrich_djvu.txt
X7vKes_pzkGhB8GP	1.7: Reading and Writing is Not Connected	1.7: Reading and Writing is Not Connected - - Last updated - Save as PDF - Cheryl E. Ball & Drew M. Loewe ed. - West Virginia University via Digital Publishing Institute and West Virginia University Libraries Author: Ellen C. Carillo, University of Connecticut Waterbury Campus. Since the 1950s we have been hearing that Johnny can’t read. In 1975, Newsweek informed us that Johnny can’t write, either. Over the years, a range of reasons for Johnny’s illiteracy have been offered. Most recently, technology has been named one of the culprits. Johnny spends too much time on the computer and not enough time reading books. He spends so much time texting and tweeting that he has forgotten how to write correctly, how to spell, how to develop ideas in more than 140 characters. Public outcries about literacy (or lack thereof) often lead to a closer look at the education system. The public raises questions surrounding why colleges and universities in particular—where Johnny would be expected to gain in-depth and comprehensive literacy skills— are not doing a better job. What is often neglected in these public debates about the best way to teach literacy at the college level is that reading and writing are connected practices and, as such, the best way to teach them is together. It is a bad idea to continue privileging writing at the expense of reading. This problematic separation of the connected practices of reading and writing is no longer an issue in students’ early schooling, where they are taught reading and writing simultaneously. Although it took decades for elementary school teachers and curricula developers to realize that young children need not learn how to read before they learned how to write, language arts instructors now teach reading and writing alongside each other. They do so because research has shown that students learn to read and write better when they are instructed in both simultaneously. This research, for example, shows that students’ phonic skills are reinforced when children practice both reading and writing the same words. As they get a little older, students begin to develop an awareness of genres or types of text, which, like the study of phonics, is also further reinforced by a concurrent focus on reading and writing. As students read (or are read to) they learn to recognize typical elements of fiction, which they then imitate in their own writing and stories. Even a two-year-old who has been read to consistently will recognize that “once upon a time” indicates the beginning of a story, and will often begin that same way when asked to make up his or her own. By the time students arrive in college, stories beginning with “once upon a time” are long gone, and in their place are difficult and dense texts—often multimedia texts— from a range of fields each with its own set of conventions. Instead of drawing on models of early literacy education that focus on teaching reading and writing simultaneously, college and universities largely privilege writing over reading. This hierarchy is evidenced by the universal firstyear writing requirement in American colleges and universities, as well as by writing across the curriculum programs. The integrated approach to teaching reading and writing falls away to students’ peril and causes great frustration in the professors who often attribute students’ struggles in their courses to poor writing ability, when these problems are often related to students’ reading difficulties. While students’ eyes may make their way over every word, that does not mean that students have comprehended a text or that they are prepared to successfully complete the writing tasks associated with the reading, which often involve summary, analysis, interpretation, and evaluation. More importantly, if students are not given the opportunity to continue working on their reading throughout their college careers, they may struggle analyzing, interpreting, and evaluating all that surrounds them since comprehension is a crucial step toward these more advanced interpretive practices. Students may lack the ability to read the world around them because they do not have the tools to recognize the values and assumptions that inform the images, advertisements, news stories, political campaigns, and ideas with which they come into contact on a daily basis. By not focusing on reading as an equally creative and active enterprise as writing—very much writing’s counterpart in the creation of meaning—colleges and universities are potentially producing students, or citizens, who think reading is passive. These students might blindly accept whatever comes their way rather than actively engaging ideas, asking questions, and seeking out multiple perspectives. Although writing is more often thought of as a creative act, reading is just as creative. When one writes, one is creating meaning by putting words and ideas together. When one reads, the same thing is happening. Although someone else has already put the words and ideas together, the reader interacts with those and creates meaning by bringing her perspective, personal experiences, and background to what literary scholar Louise Rosenblatt has called the transaction between the text and reader. This is why a few people might read the same novel but each take something different from it. That personal transaction with the text has affected how each reader creates meaning. When reading and writing are taught alongside each other in the college-level classroom, students can gain practice experiencing and relishing in opportunities to create meaning not just through writing, but through reading everything from print texts to art to websites to national news events, all of which they will continue to engage beyond school. Focusing on active reading approaches, including everything from comprehension strategies to ways of determining something’s inherent values and biases to productive methods of responding, is crucial if students are going to leave postsecondary institutions prepared to be informed, aware, and engaged citizens. Unfortunately, there is still a great deal of work to be done since recent studies such as The Citation Project, a multi-institutional, and empirical research project show that students’ reading abilities are largely underdeveloped. This research seeks to understand how students read sources and use them in their writing. With less than 10% of students using summary in their writing (as opposed to paraphrasing, copying, and citing), scholar Rebecca Moore Howard and her colleagues noted that their findings raise questions about students’ abilities to understand what they are reading. Recent studies from Education Testing Services have corroborated these findings as did findings from studies conducted by ACT, Inc. and the Pew Charitable Trust, which found that close to half of the college students in their samples did not meet minimum benchmarks for literacy or lacked reading proficiency. These deficiencies are major problems particularly in this digital age for, as literacy scholar Donald Leu and his colleagues have pointed out, foundational literacies such as reading and writing print text will continue to play a crucial role—and maybe even a more essential role—in this digital age because of the proliferation of information. Because there is so much at stake, educators and the public must keep the connections between reading and writing in mind as we continue to engage in debates about the best practices for teaching literacy. The value of literacy undoubtedly extends far beyond school. To read and to write is to create, to interpret. If education is, in fact, a means to preparing citizens to function and participate within a democracy then reading and writing—and the interpretive skills they inculcate—are crucial. As research has shown, teaching them alongside each other reinforces both skills. Even if we want to be a bit cynical and argue that postsecondary education has become nothing more than a necessary, but burdensome, step to gaining employment, both reading and writing are still just as important. A 2011 survey found that 86% of corporate recruiters said strong communication skills were a priority—well ahead of the next skill. In a 2013 survey of 318 employers published by the Association of American Colleges and Universities, 80% of employers said colleges should focus more on written and oral communication. In these and similar studies, communication is defined by reading and writing abilities. Employers want to hire people who can communicate effectively, and despite our culture’s recent celebration of all things STEM, many employers continue to vocalize the importance of effective communication skills. Teaching reading and writing together will help students become more proficient in both. Developing those communication skills means that those of us within education should look at the curricula we teach and/ or administer and ask ourselves if we have fallen into the trap of compartmentalizing reading and writing to the detriment of our students. If we have, we must ask ourselves: how might we better integrate attention to both reading and writing in order to enrich the literacy education we are providing? We must not assume that simply exposing students to texts of all kinds and across all media will automatically result in comprehension. Instructors must deliberately teach students how to actively read the words and images and, by extension, the world around them. Instructors must do so not only so students can succeed in their courses, but so that students can be prepared to actively engage in the complex interpretive work that is expected of citizens in an information-rich culture. We are all encountering more text and visual images than ever before. There is a great deal at stake if we don’t take the opportunity to teach active reading alongside writing. Instructors need to teach students different strategies for reading the complex texts they will encounter throughout their academic careers and in the world. One of these strategies might be rhetorical reading wherein readers pay particular attention to how a text is working on them, persuading them. A better understanding of this as a reader can also support students’ writing as they develop their own arguments. Instructors might also provide a strategy such as reading like a writer, wherein readers notice the choices a writer has made and understands the relevance of those choices to their own writing. Without explicit attention to reading and the relationship between reading and writing, students will not have strategies for making sense of new or difficult texts, arguments, images, and ideas they encounter. Denying students the richness of an education that considers reading and writing alongside each other means denying them the opportunity to become as proficient as possible in these connected practices and, therefore, experience and practice the interpretive work that is specifically human. Further Reading For the media’s contemporary coverage of the ongoing literacy crisis, see Sofia Westin’s “Social Media Eroding Skills?” ( The Philadelphia Inquirer ), the Bloomberg News report “U.S. Teens Report Decline in Writing Skills,” and Michael Rosenwald’s “Serious Reading Takes a Hit from Online Scanning and Skimming” ( The Washington Post ). For historical coverage of this phenomenon see Rudolf Fleisch’s Why Can’t Johnny Read? and Merrill Sheils’s “Why Johnny Can’t Write” ( Newsweek ). For contemporary, scholarly approaches that emphasize the importance of simultaneous instruction in reading and writing, particularly at the postsecondary level, see Robert Scholes’s “The Transition to College Reading,” Linda Adler-Kassner and Heidi Estrem’s “Reading Practices in the Writing Classroom,” Alice S. Horning and Elizabeth Kraemer’s Reconnecting Reading and Writing , David Jolliffe’s “Learning to Read as Continuing Education,” David Jolliffe and Allison Harl’s “Studying the ‘Reading Transition’ from High School to College: What Are Our Students Reading and Why?,” and Mike Bunn’s “Motivation and Connection: Teaching Reading (and Writing) in the Composition Classroom.” Keywords literacy acquisition, literacy, new literacies, reading pedagogies, reading wars, reading–writing connections Author Bio Ellen C. Carillo is associate professor of English at the University of Connecticut and the writing program administrator at its Waterbury campus. She is the author of Securing a Place for Reading in Composition: The Importance of Teaching for Transfer , as well as articles and chapters on the place of reading in the teaching of writing. Ellen has earned grants to conduct research on reading–writing connections in the classroom and regularly presents her findings and scholarship at national conferences. She is also a founding member and co-leader of “The Role of Reading in Composition Studies” special interest group, which meets at the Conference on College Composition and Communication’s annual convention.	2,639	common-pile/libretexts_filtered	https://human.libretexts.org/Courses/Solano_Community_College/Bad_Ideas_About_Writing/01%3A_Bad_Ideas_About_What_Good_Writing_is_.../1.07%3A_Reading_and_Writing_is_Not_Connected	libretexts	libretexts-0000.json.gz:48815	https://human.libretexts.org/Courses/Solano_Community_College/Bad_Ideas_About_Writing/01%3A_Bad_Ideas_About_What_Good_Writing_is_.../1.07%3A_Reading_and_Writing_is_Not_Connected
PVUXcfImA3clNbLz	4.7: Tachyons and Faster-than-Light (FTL)	4.7: Tachyons and Faster-than-Light (FTL) Learning Objectives - Explain faster-than-light ( FTL , superluminal) motion in relativity A Defense in Depth Let’s summarize some ideas about faster-than-light ( FTL , superluminal) motion in relativity: - Superluminal transmission of information would violate causality, since it would allow a causal relationship between events that were spacelike in relation to one another, and the timeordering of such events is different according to different observers. Since we never seem to observe causality to be violated, we suspect that superluminal transmission of information is impossible. This leads us to interpret the metric in relativity as being fundamentally a statement of possible cause and effect relationships between events. - We observe the invariant mass defined by $m^2 = E^2 - p^2$ to be a fixed property of all objects. Therefore we suspect that it is not possible for an object to change from having $\|E\| > \|p\|$ to having $\|E\| < \|p\|$. - No continuous process of acceleration can bring an observer from $v < c$ to $v > c$ (see section 3.3). Since it’s possible to build an observer out of material objects, it seems that it’s impossible to get a material object past $c$ by a continuous process of acceleration. - If superluminal motion were possible, then one might also expect superluminal observers to be possible. But FTL frames of reference are kinematically impossible in $3 + 1$ dimensions ( section 3.8). Thus special relativity seems to have a defense in depth against superluminal motion. Based on 2, FTL motion would be a property of an exotic form of matter built out of hypothetical particles with imaginary mass. Such particles are called tachyons. An imaginary mass is not absurd on its face, because experiments directly measure $E$ and $p$, not $m$. E.g., if we put a tachyon on a scale and weighed it, we would be measuring its mass-energy $E$. The weakest of these arguments is 1, since as described in section 2.1, we have no strong reasons for believing in causality as an overarching principle of physics. It would be exciting if we could detect tachyons in particle accelerator experiments or as naturally occurring radiation. Perhaps we could even learn to transmit and receive tachyon signals artificially, allowing us to send ourselves messages from the future! This possibility was pointed out in 1917 by Tolman 1 and is referred to as the “tachyonic antitelephone.” 2If we’re willing to let go of causality, then we just need to make sure that our tachyons comply with items 3 and 4 above. Argument 4 tells us that the laws of physics must conspire to make it impossible to build an observer out of tachyons; this is not entirely implausible, since there are other classes of particles such as photons that can’t be used to construct observers. Experiments to search for tachyons Experimental searches are made more difficult by conﬂicting theoretical claims as to whether tachyons should be charged or neutral, whether they should have integral or half-integral spin, and whether the normal spin-statistics relation even applies to them. 3 If charged, it is uncertain whether and under what circumstances they would emit Cerenkov radiation. The most obvious experimental signature of tachyons would be propagation at speeds greater than $c$. Negative results were reported by Murthy and later by Clay, 4 who studied air showers generated by cosmic rays to look for precursor particles that arrived before the first photons. One could also look for particles with $\|p\| > \|E\|$. Alvager and Erman, in a 1965 experiment, studied the beta decay of $^{170}\textrm{Tm}$, using a spectrometer to measure the momentum of charged radiation and a solid state detector to determine energy. An upper limit of one tachyon per $10^4$ beta particles was inferred. If tachyons are neutral, then they might be difficult to detect directly, but it might be possible to infer their existence indirectly through missing energy-momentum in reactions. This is how the neutrino was first discovered. Baltay et al . 5 searched for reactions such as \[\bar{p} + p \rightarrow \pi ^{+} + \pi ^{-} + t\] with $t$ being a neutral tachyon, by measuring the momenta of all the other initial and final particles and looking for events in which the missing energy-momentum was spacelike. They put upper limits of $\sim 10^{-3}$ on the branching ratios of this and several other reactions leading to production of single tachyons or tachyon-antitachyon pairs. For a long time after the discovery of the neutrino, very little was known about its mass, so it was consistent with the experimental evidence to imagine that one or more species of neutrinos were tachyons, and Chodos et al . made such speculations in 1985. A brief ﬂurry of reawakened interest in tachyons was occasioned by a 2011 debacle in which the particle-physics experiment OPERA mistakenly reported faster-than-light propagation of neutrinos; the anomaly was later found to be the result of a loose connection on a fiber-optic cable plus a miscalibrated oscillator. An experiment called KATRIN, currently nearing the start of operation at Karlsruhe, will provide the first direct measurement of the mass of the neutrino, by measuring very precisely the maximum energy of the electrons emitted in the decay of tritium, $^{3}\textrm{H} \rightarrow ^{3}\textrm{He} + e^{-} + \bar{v_e}$. Conservation of energy then allows one to determine the minimum energy of the antineutrino, which is related to its mass and momentum by $m^2 = E^2 - p^2$. Because $m^2$ appears in this equation, the experiment really measures $m^2$, not $m$, and a result of $m^2 < 0$ would bring the tachyonic neutrino back from the grave. Tachyons and Quantum Mechanics When we add quantum mechanics to special relativity, we get quantum field theory , which sounds scary and can be quite technical, but is governed by some very simple principles. One of these principles is that “ everything not forbidden is compulsory .” The phrase was popularized as a political satire of communism by T.H. White, but was commandeered by physicist Murray Gell-Mann to express the idea that any process not forbidden by a conservation law will in fact occur in nature at some rate. If tachyons exist, then it is possible to have two tachyons whose energy-momentum vectors add up to zero. This would seem to imply that the vacuum could spontaneously create tachyon-antitachyon pairs. Most theorists now interpret this as meaning that when tachyons pop up in the equations, it’s a sign that the assumed vacuum state is not stable, and will change into some other state that is the true state of minimum energy. References 1 www.archive.org/details/theoryrelativmot00tolmrich 2 Bilaniuk et al. claimed in a 1962 paper to have found a reinterpretation that eliminated the causality violation, but their interpretation requires that rates of tachyon emission in one frame be related to rates of tachyon absorption in another frame, which in my opinion is equally problematic, since rates of absorption should depend on the environment, whereas rates of emission should depend on the emitter; the causality violation has simply been described in different words, but not eliminated. For a different critique, see Benford, Book, and Newcomb, “The tachyonic antitelephone,” Physical Review D 2 (1970) 263. Scans of the paper can be found online. 3 Feinberg, “Possibility of Faster-Than-light Particles,” Phys Rev 159 (1967) 1089, http://www.scribd.com/doc/144943457/ G-Feinberg-Possibility-of-Faster-Than-light-Particles-Phys-Rev-159-1967-1089 4 “A search for tachyons in cosmic ray showers,” Austr. J. Phys 41 (1988) 93, http://adsabs.harvard.edu/full/1988AuJPh..41...93C 5 Phys. Rev. D 1 (1970) 759	1,610	common-pile/libretexts_filtered	https://phys.libretexts.org/Bookshelves/Relativity/Special_Relativity_(Crowell)/04%3A_Dynamics/4.07%3A_Tachyons_and_Faster-than-Light_(FTL)	libretexts	libretexts-0000.json.gz:19459	https://phys.libretexts.org/Bookshelves/Relativity/Special_Relativity_(Crowell)/04%3A_Dynamics/4.07%3A_Tachyons_and_Faster-than-Light_(FTL)
imgX-QkVWN3lJm0L	Introduction to Welding	7.5 References Douglas Rupik, M.Ed., JIW Occupational Safety and Health Administration. (n.d.). Shipyard employment eTool: General requirements–General working conditions. U.S. Department of Labor. https://www.osha.gov/etools/shipyard/general-requirements/working-conditions Occupational Safety and Health Administration. (n.d.). Shipyard employment eTool: Ship repair–Confined or enclosed spaces and other dangerous atmospheres. U.S. Department of Labor. https://www.osha.gov/etools/shipyard/ship-repair/confined-spaces Occupational Safety and Health Administration. (2015). Trenching and excavation safety. OSHA.gov. https://www.osha.gov/sites/default/files/publications/osha2226.pdf Zippia. (2021, January 29). Welder demographics and statistics in the US. Zippia.com. https://www.zippia.com/welder-jobs/demographics/	93	common-pile/pressbooks_filtered	https://openwa.pressbooks.pub/welding1/chapter/wa7-5/	pressbooks	pressbooks-0000.json.gz:47559	https://openwa.pressbooks.pub/welding1/chapter/wa7-5/
Nqq0e3euxwXlydw1	Texas Government	35 Composition Learning Objectives At the end of this section you’ll be able to: - Understand the partisan make up of the Texas State Legislature - Understand the gender makeup of the Texas State Legislature - Understand the racial makeup of the Texas State Legislature Introduction It’s often been said the Texas State Legislature is “pale, male, and stale.” This may not be quite as accurate as in the past, but the Texas State Legislature is prodominantly white, male, and middle aged. Partisan Makeup The Republican Party controls both the Texas State House of Representatives and the Texas State Senate: - The Texas State House of Representatives currently has 93 Republicans, 56 Democrats, and one vacancy. - The Texas State Senate currently has 20 Republicans and 11 Democrats Gender Makeup The Texas State Legislature is predominantly male. - Approximately 81% of the Texas State House of Representatives is male (121 males, 29 females) - Approximately 74% of the Texas State Senate is male (23 males, 8 females) - Take together, almost 80% of the total membership of the Texas State Legislature is male (144 of 181 total members) Racial Makeup Approximately two-thirds of the Texas State Legislature is white. The 84th Legislature (beginning 2015) was composed as follows: - 115 White members - 41 Hispanic members - 19 African-American members - 3 Asian members	291	common-pile/pressbooks_filtered	https://library.achievingthedream.org/austincctexasgovernment/chapter/composition/	pressbooks	pressbooks-0000.json.gz:36120	https://library.achievingthedream.org/austincctexasgovernment/chapter/composition/
YOUANtarD-MbeXV8	28.4: The African American Struggle for Civil Rights	28.4: The African American Struggle for Civil Rights In the aftermath of World War II, African Americans began to mount organized resistance to racially discriminatory policies in force throughout much of the United States. In the South, they used a combination of legal challenges and grassroots activism to begin dismantling the racial segregation that had stood for nearly a century following the end of Reconstruction. Community activists and civil rights leaders targeted racially discriminatory housing practices, segregated transportation, and legal requirements that African Americans and whites be educated separately. While many of these challenges were successful, life did not necessarily improve for African Americans. Hostile whites fought these changes in any way they could, including by resorting to violence. EARLY VICTORIES During World War II, many African Americans had supported the “Double V Campaign,” which called on them to defeat foreign enemies while simultaneously fighting against segregation and discrimination at home. After World War II ended, many returned home to discover that, despite their sacrifices, the United States was not willing to extend them any greater rights than they had enjoyed before the war. Particularly rankling was the fact that although African American veterans were legally entitled to draw benefits under the GI Bill, discriminatory practices prevented them from doing so. For example, many banks would not give them mortgages if they wished to buy homes in predominantly African American neighborhoods, which banks often considered too risky an investment. However, African Americans who attempted to purchase homes in white neighborhoods often found themselves unable to do so because of real estate covenants that prevented owners from selling their property to blacks. Indeed, when a black family purchased a Levittown house in 1957, they were subjected to harassment and threats of violence. For a look at the experiences of an African American family that tried to move to a white suburban community, view the 1957 documentary Crisis in Levittown . The postwar era, however, saw African Americans make greater use of the courts to defend their rights. In 1944, an African American woman, Irene Morgan, was arrested in Virginia for refusing to give up her seat on an interstate bus and sued to have her conviction overturned. In Morgan v. the Commonwealth of Virginia in 1946, the U.S. Supreme Court ruled that the conviction should be overturned because it violated the interstate commerce clause of the Constitution. This victory emboldened some civil rights activists to launch the Journey of Reconciliation, a bus trip taken by eight African American men and eight white men through the states of the Upper South to test the South’s enforcement of the Morgan decision. Other victories followed. In 1948, in Shelley v. Kraemer , the U.S. Supreme Court held that courts could not enforce real estate covenants that restricted the purchase or sale of property based on race. In 1950, the NAACP brought a case before the U.S. Supreme Court that they hoped would help to undermine the concept of “separate but equal” as espoused in the 1896 decision in Plessy v. Ferguson , which gave legal sanction to segregated school systems. Sweatt v. Painter was a case brought by Herman Marion Sweatt, who sued the University of Texas for denying him admission to its law school because state law prohibited integrated education. Texas attempted to form a separate law school for African Americans only, but in its decision on the case, the U.S. Supreme Court rejected this solution, holding that the separate school provided neither equal facilities nor “intangibles,” such as the ability to form relationships with other future lawyers, that a professional school should provide. Not all efforts to enact desegregation required the use of the courts, however. On April 15, 1947, Jackie Robinson started for the Brooklyn Dodgers, playing first base. He was the first African American to play baseball in the National League, breaking the color barrier. Although African Americans had their own baseball teams in the Negro Leagues, Robinson opened the gates for them to play in direct competition with white players in the major leagues. Other African American athletes also began to challenge the segregation of American sports. At the 1948 Summer Olympics, Alice Coachman, an African American, was the only American woman to take a gold medal in the games ( Figure ). These changes, while symbolically significant, were mere cracks in the wall of segregation. DESEGREGATION AND INTEGRATION Until 1954, racial segregation in education was not only legal but was required in seventeen states and permissible in several others ( Figure ). Utilizing evidence provided in sociological studies conducted by Kenneth Clark and Gunnar Myrdal, however, Thurgood Marshall, then chief counsel for the NAACP, successfully argued the landmark case Brown v. Board of Education of Topeka, Kansas before the U.S. Supreme Court led by Chief Justice Earl Warren. Marshall showed that the practice of segregation in public schools made African American students feel inferior. Even if the facilities provided were equal in nature, the Court noted in its decision, the very fact that some students were separated from others on the basis of their race made segregation unconstitutional. As a law student in 1933, Thurgood Marshall ( Figure ) was recruited by his mentor Charles Hamilton Houston to assist in gathering information for the defense of a black man in Virginia accused of killing two white women. His continued close association with Houston led Marshall to aggressively defend blacks in the court system and to use the courts as the weapon by which equal rights might be extracted from the U.S. Constitution and a white racist system. Houston also suggested that it would be important to establish legal precedents regarding the Plessy v. Ferguson ruling of separate but equal. By 1938, Marshall had become “Mr. Civil Rights” and formally organized the NAACP’s Legal Defense and Education Fund in 1940 to garner the resources to take on cases to break the racist justice system of America. A direct result of Marshall’s energies and commitment was his 1940 victory in a Supreme Court case, Chambers v. Florida , which held that confessions obtained by violence and torture were inadmissible in a court of law. His most well-known case was Brown v. Board of Education in 1954, which held that state laws establishing separate public schools for black and white students were unconstitutional. Later in life, Marshall reflected on his career fighting racism in a speech at Howard Law School in 1978: When Marshall says that the problems of racism have not been solved, to what was he referring?Be aware of that myth, that everything is going to be all right. Don’t give in. I add that, because it seems to me, that what we need to do today is to refocus. Back in the 30s and 40s, we could go no place but to court. We knew then, the court was not the final solution. Many of us knew the final solution would have to be politics, if for no other reason, politics is cheaper than lawsuits. So now we have both. We have our legal arm, and we have our political arm. Let’s use them both. And don’t listen to this myth that it can be solved by either or that it has already been solved. Take it from me, it has not been solved. Plessy v. Fergusson had been overturned. The challenge now was to integrate schools. A year later, the U.S. Supreme Court ordered southern school systems to begin desegregation “with all deliberate speed.” Some school districts voluntarily integrated their schools. For many other districts, however, “deliberate speed” was very, very slow. It soon became clear that enforcing Brown v. the Board of Education would require presidential intervention. Eisenhower did not agree with the U.S. Supreme Court’s decision and did not wish to force southern states to integrate their schools. However, as president, he was responsible for doing so. In 1957, Central High School in Little Rock, Arkansas, was forced to accept its first nine African American students, who became known as the Little Rock Nine . In response, Arkansas governor Orval Faubus called out the state National Guard to prevent the students from attending classes, removing the troops only after Eisenhower told him to do so. A subsequent attempt by the nine students to attend school resulted in mob violence. Eisenhower then placed the Arkansas National Guard under federal control and sent the U.S. Army’s 101st airborne unit to escort the students to and from school as well as from class to class ( Figure ). This was the first time since the end of Reconstruction that federal troops once more protected the rights of African Americans in the South. Throughout the course of the school year, the Little Rock Nine were insulted, harassed, and physically assaulted; nevertheless, they returned to school each day. At the end of the school year, the first African American student graduated from Central High. At the beginning of the 1958–1959 school year, Orval Faubus ordered all Little Rock’s public schools closed. In the opinion of white segregationists, keeping all students out of school was preferable to having them attend integrated schools. In 1959, the U.S. Supreme Court ruled that the school had to be reopened and that the process of desegregation had to proceed. WHITE RESPONSES Efforts to desegregate public schools led to a backlash among most southern whites. Many greeted the Brown decision with horror; some World War II veterans questioned how the government they had fought for could betray them in such a fashion. Some white parents promptly withdrew their children from public schools and enrolled them in all-white private academies, many newly created for the sole purpose of keeping white children from attending integrated schools. Often, these “academies” held classes in neighbors’ basements or living rooms. Other white southerners turned to state legislatures or courts to solve the problem of school integration. Orders to integrate school districts were routinely challenged in court. When the lawsuits proved unsuccessful, many southern school districts responded by closing all public schools, as Orval Faubus had done after Central High School was integrated. One county in Virginia closed its public schools for five years rather than see them integrated. Besides suing school districts, many southern segregationists filed lawsuits against the NAACP, trying to bankrupt the organization. Many national politicians supported the segregationist efforts. In 1956, ninety-six members of Congress signed “The Southern Manifesto,” in which they accused the U.S. Supreme Court of misusing its power and violating the principle of states’ rights , which maintained that states had rights equal to those of the federal government. Unfortunately, many white southern racists, frightened by challenges to the social order, responded with violence. When Little Rock’s Central High School desegregated, an irate Ku Klux Klansman from a neighboring community sent a letter to the members of the city’s school board in which he denounced them as Communists and threatened to kill them. White rage sometimes erupted into murder. In August 1955, both white and black Americans were shocked by the brutality of the murder of Emmett Till. Till, a fourteen-year-old boy from Chicago, had been vacationing with relatives in Mississippi. While visiting a white-owned store, he had made a remark to the white woman behind the counter. A few days later, the husband and brother-in-law of the woman came to the home of Till’s relatives in the middle of the night and abducted the boy. Till’s beaten and mutilated body was found in a nearby river three days later. Till’s mother insisted on an open-casket funeral; she wished to use her son’s body to reveal the brutality of southern racism. The murder of a child who had been guilty of no more than a casual remark captured the nation’s attention, as did the acquittal of the two men who admitted killing him. THE MONTGOMERY BUS BOYCOTT One of those inspired by Till’s death was Rosa Parks, an NAACP member from Montgomery, Alabama, who became the face of the 1955–1956 Montgomery Bus Boycott. City ordinances in Montgomery segregated the city’s buses, forcing African American passengers to ride in the back section. They had to enter through the rear of the bus, could not share seats with white passengers, and, if the front of the bus was full and a white passenger requested an African American’s seat, had to relinquish their place to the white rider. The bus company also refused to hire African American drivers even though most of the people who rode the buses were black. On December 1, 1955, Rosa Parks refused to give her seat to a white man, and the Montgomery police arrested her. After being bailed out of jail, she decided to fight the laws requiring segregation in court. To support her, the Women’s Political Council, a group of African American female activists, organized a boycott of Montgomery’s buses. News of the boycott spread through newspaper notices and by word of mouth; ministers rallied their congregations to support the Women’s Political Council. Their efforts were successful, and forty thousand African American riders did not take the bus on December 5, the first day of the boycott. Other African American leaders within the city embraced the boycott and maintained it beyond December 5, Rosa Parks’ court date. Among them was a young minister named Martin Luther King, Jr. For the next year, black Montgomery residents avoided the city’s buses. Some organized carpools. Others paid for rides in African American-owned taxis, whose drivers reduced their fees. Most walked to and from school, work, and church for 381 days, the duration of the boycott. In June 1956, an Alabama federal court found the segregation ordinance unconstitutional. The city appealed, but the U.S. Supreme Court upheld the decision. The city’s buses were desegregated. Section Summary After World War II, African American efforts to secure greater civil rights increased across the United States. African American lawyers such as Thurgood Marshall championed cases intended to destroy the Jim Crow system of segregation that had dominated the American South since Reconstruction. The landmark Supreme Court case Brown v. Board of Education prohibited segregation in public schools, but not all school districts integrated willingly, and President Eisenhower had to use the military to desegregate Little Rock’s Central High School. The courts and the federal government did not assist African Americans in asserting their rights in other cases. In Montgomery, Alabama, it was the grassroots efforts of African American citizens who boycotted the city’s bus system that brought about change. Throughout the region, many white southerners made their opposition to these efforts known. Too often, this opposition manifested itself in violence and tragedy, as in the murder of Emmett Till. Review Questions The NAACP lawyer who became known as “Mr. Civil Rights” was ________. - Earl Warren - Jackie Robinson - Orval Faubus - Thurgood Marshall D The Arkansas governor who tried to prevent the integration of Little Rock High School was ________. - Charles Hamilton Houston - Kenneth Clark - OrvalFaubus - Clark Clifford C What was the significance of Shelley v. Kraemer ? Shelley v. Kraemer held that state courts could not enforce agreements that prevented homeowners from selling to members of particular races. The ruling made it easier for African Americans to purchase houses in neighborhoods of their choosing. Glossary - desegregation - the removal of laws and policies requiring the separation of different racial or ethnic groups - Little Rock Nine - the nickname for the nine African American high school students who first integrated Little Rock’s Central High School - states’ rights - the political belief that states possess authority beyond federal law, which is usually seen as the supreme law of the land, and thus can act in opposition to federal law	3,404	common-pile/libretexts_filtered	https://human.libretexts.org/Bookshelves/History/National_History/U.S._History_(OpenStax)/28%3A_Post-War_Prosperity_and_Cold_War_Fears_1945-1960/28.04%3A_The_African_American_Struggle_for_Civil_Rights	libretexts	libretexts-0000.json.gz:4102	https://human.libretexts.org/Bookshelves/History/National_History/U.S._History_(OpenStax)/28%3A_Post-War_Prosperity_and_Cold_War_Fears_1945-1960/28.04%3A_The_African_American_Struggle_for_Civil_Rights
indl_22-dgn6xBUJ	20.3: Evaluation Strategies	20.3: Evaluation Strategies By the end of this section, you should be able to: - Describe an intervention evaluation plan for public health services for individuals, families, and groups. - Utilize a systematic process to direct the evaluation of public health interventions. - Evaluate outcomes of action plans and interventions, considering implications for practice. Evaluation of community programs occurs throughout implementation and at the conclusion of a program to improve processes and outcomes. The evaluation provides evidence for decisions regarding the program, such as whether the program should continue, if revisions are needed, or if the program should be discontinued. Additionally, evaluation may either be mandated by external funders, driven by a need to determine program effectiveness, or both (Centers for Disease Control and Prevention [CDC], 2012). The program team develops a plan for evaluation during the planning phases of community health programming, determining the evaluation methods before beginning intervention activities. Using a systematic process ensures all components of the program are evaluated in an evidence-based way. No matter the process and methods used, the program team evaluates whether goals and objectives of the program are met. If a health program fails to meet the goals and objectives or the community’s needs, the team should carefully consider the program’s future. Evaluation Planning for Public Health Programs Program evaluation is the ongoing, systematic collection, analysis, and use of data to examine program efficacy , effectiveness , and efficiency to make decisions about current and future health programs (CDC, 2012; Issel & Wells, 2018). Efficacy is the “maximum potential effect under ideal conditions” (Issel & Wells, 2018, p. 222). Ideal conditions are difficult to create in community health programs, so efficacy is rarely evaluated. Effectiveness is the community program’s ability to achieve the desired outcome in real-life settings (Issel & Wells, 2018). It is usually measured using statistical data and comparisons to benchmarks. Efficiency occurs when the effect of program interventions, or outputs, are greater than the resources, or inputs, used to provide the intervention (Issel & Wells, 2018). The program team plans for evaluation in order to: - monitor progress toward program goals and objectives, - decide if program activities and components are leading to the desired results, - make comparisons among program participants and other populations, - provide rationale for further funding and support, - ensure continuous quality improvement, - verify program maintenance and efficient use of resources, - document accountability that the program is fulfilling its purpose and meeting goals, and - justify sustaining, revising, or discontinuing the program (CDC, 2021). As noted, the program team plans for evaluation during the program planning process and prior to implementing interventions. Steps to planning for program evaluation include the following: - Identify individuals and groups to plan and assist with evaluation. - Meet with the program team to determine how to evaluate the program. - Examine evaluation types and processes used in the literature. - Choose the type of evaluation to be used and a systematic process that aligns with evaluation needs and program goals. - Determine what program goals and objectives will be measured, how they will be measured, who will be responsible for collecting data, and what resources are available. - Write the program evaluation plan using the types of evaluation and chosen systematic process. The program team determines which type of community health program evaluation will be conducted. The most common types are formative evaluation , process evaluation , outcome evaluation , and impact evaluations . The choice of type depends upon program activities, organizational needs, funder requirements, and the program’s developmental stage. Formative Evaluation Formative evaluation occurs during program development to confirm that program interventions are feasible and appropriate (CDC, 2014). Most often, formative evaluation occurs during new program development or when an existing program is revised. Formative evaluation includes a community health needs assessment as discussed in Assessment, Analysis, and Diagnosis. Process Evaluation Process evaluation focuses on program implementation processes to determine if the program has been implemented efficiently and as planned. It occurs throughout program implementation, allowing for mid-program revisions and following the program to provide direction for future program improvement. As such, process evaluation should occur to some extent for all community health programs. During process evaluation, the program team describes the program’s inputs and outputs. Program inputs are those things and resources required to carry out the program; examples are personnel number and experience, volunteers, informational and technological resources, financial resources and budget, physical location and resources, transportation needs, leadership, time, marketing needs, and other resources needed to complete activities (Issel & Wells, 2018). Program outputs are things accomplished using inputs. Examples of outputs are population reach; number of participants; intervention dose and amount; equipment or incentives distributed; partnerships developed; staff and volunteer hours worked; extent that the budget was followed; quality of information, technological, and physical resources; and staff, volunteer, and participant satisfaction (Issel & Wells, 2018). Most often, the team describes inputs and outputs using qualitative data, but they may use some quantitative data. The program team explains what and how much was accomplished during the program and determines strengths, areas for improvement, and recommendations for ongoing and future program implementation. Outcome Evaluation Outcome evaluation assesses the extent to which the program achieves its objectives within the target population and its effect on the target populations’ knowledge, attitudes, and behaviors (CDC, 2014). This is an evaluation of the SMART objectives developed during the program development planning stages (Figure 20.2). Planning Health Promotion and Disease Prevention Interventions guides the nurse in the development of SMART objectives . Outcome evaluation should be completed for all community health programs regardless of developmental level. Typically, outcome evaluations are quantitative and include short-, medium-, and long-term measures of change. At times, the team may use qualitative data to provide support for quantitative results. It is recommended that process and outcome evaluation occur simultaneously because if a program objective is not met, it could be a result of implementation process issues (CDC, 2014). Impact Evaluation Impact evaluation determines the degree to which the community health program has achieved its primary goal (CDC, 2014). It occurs during an existing program, if appropriate, and at the end of a program and most often uses data collected over the long term, including community health assessment data and benchmarks. Most impact evaluations are quantitative. For example, an evaluation might compare pre-program and post-program morbidity, mortality, and health behavior data for the target population and community as a whole. Various program evaluation types are available to determine if a community health program has been effectively and efficiently implemented. This video describes formative, process, impact, and outcome evaluations. Watch the video, and then respond to the following questions. - How does the nurse and program team determine which type of program evaluation should be used? - What evaluation designs are used to conduct program outcome evaluations? Systematic Processes to Direct Program Evaluation The nurse in collaboration with the program planning team chooses an evaluation framework or tool to guide evaluation planning. Frameworks and tools provide systematic, evidence-based resources to organize important program evaluation components. Commonly used frameworks and tools include the CDC Framework for Program Evaluation in Public Health (CDC, 1999), Public Health Ontario’s steps for evaluating health promotion programs (Ontario Agency for Health Protection and Promotion [OAHPP] et al., 2016), and logic models . CDC’s Framework for Program Evaluation in Public Health The CDC Framework for Program Evaluation in Public Health is commonly used to summarize elements of program evaluation to assign value and judge a community health program based on evidence. The program team assigns value related to program quality, cost-effectiveness, and significance of the health problem. The framework contains two elements: six steps of program evaluation and standards to assess the quality of evaluation (Figure 20.3) (CDC, 1999). While the program team does not need to conduct the evaluation in a linear sequence, they must thoroughly address each step. Table 20.5 provides examples of activities that occur during each step of program evaluation. \| Steps of Program Evaluation \| Examples of Activities \| \|---\|---\| \| Engage interested parties \| \| \| Describe the program \| \| \| Focus on the evaluation design \| \| \| Gather credible evidence \| \| \| Justify conclusions \| \| \| Ensure the use and share lessons learned \| \| The program team incorporates the standards of utility, feasibility, propriety, and accuracy throughout program evaluation. Utility standards include determining who needs evaluation information, what information they need, the evaluation’s purpose, and how the information will be used (CDC, 1999). Feasibility standards involve considering resources available to conduct program evaluation, including money, time, and effort (CDC, 1999). Propriety standards confirm that program evaluation is fair and ethical (CDC, 1999). Accuracy standards substantiate that program evaluation methods, data, and documentation are appropriate and contain accurate information (CDC, 1999). The CDC (2011) provides a workbook to guide program teams through the evaluation process. Public Health Ontario’s Steps for Evaluating Health Promotion Programs Public Health Ontario (OAHPP et al., 2016), a scientific and technical public health organization in Ontario, Canada, recommends 10 systematic steps to evaluate health promotion programs (Table 20.6). Similar to other public health evaluation frameworks, the program team conducts the first steps of program evaluation planning concurrently with program development. The program team engages interested parties, develops the program goals and objectives, determines the target population, creates program strategies and activities, and locates program resources. The organization recommends developing a logic model to represent the program to summarize its main components and to align evaluation questions with program activities (OAHPP et al., 2016). Planning Health Promotion and Disease Prevention Interventions discusses using logic models in health program planning. Process and outcome evaluation measures should be used. The program team plans to gather data using quantitative and qualitative measures to have substantial information to determine program effectiveness and make decisions regarding health programs. The program team shares findings with interested parties to solicit recommendations and make program decisions. An introductory workbook (OAHPP et al., 2016) is available to assist the program team through evaluation planning and gathering, analyzing, and reporting program data. \| Planning \| Step 1: Clarify the program \| \| Step 2: Engage interested parties \| \| \| Step 3: Assess resources and evaluability \| \| \| Step 4: Determine your evaluation questions \| \| \| Step 5: Determine appropriate methods of measurement and procedures \| \| \| Step 6: Develop an evaluation plan \| \| \| Implementation \| Step 7: Collect data \| \| Step 8: Process data and analyze results \| \| \| Utilization \| Step 9: Interpret and disseminate the results \| \| Step 10: Apply evaluation findings \| \| \| For more information, see Evaluating health promotion programs: introductory workbook . \| Logic Models Logic models are tools used to visually present the relationships among resources that are used to implement a program, the activities planned, and the intended results of a program (W. K. Kellogg Foundation, 2004). Logic models are also used to map evaluation questions and indicators. If the program team did not create a logic model during the program planning process, it is recommended that the program team create one to assist in evaluation efforts. Planning Health Promotion and Disease Prevention Interventions describes how to create a health program logic model. After creating a logic model, the team can use it to decide on process and/or outcome evaluation methods and link evaluation questions to logic model components. Logic models are used during program planning, implementation, and evaluation. This video demonstrates how to develop a logic model and provides an example using a parent training program. Watch the video, and then respond to the following questions. - What are the components of a logic model? - How does the nurse connect the logic model to program evaluation and evaluation methods? - Using what you have learned regarding types of program evaluation, which components of the logic model align with process evaluation, which components align with outcome evaluation, and which components align with impact evaluation? Evaluating Outcomes of Action Plans and Interventions A community health program’s outcomes should always be evaluated to determine if program goals and objectives have been met. Data regarding program interventions and activities should be evaluated and analyzed individually and as a whole. The SMART objectives and logic model written during the planning phase, as discussed in Planning Health Promotion and Disease Prevention Interventions, are used to develop evaluation questions and determine data collection techniques. Data collection techniques include questionnaires to measure knowledge, attitudes, or behavior; observation; interviews; focus groups; and epidemiologic data. The team may collect data from participants, staff, volunteers, and community partners. Participants should always be evaluated to determine knowledge, attitude, or behavior changes. The team may collect pre-implementation or baseline data from epidemiological data, community health assessments, and participant surveys prior to program interventions. Short-term objectives are often measured immediately following program intervention. Intermediate objectives are measured within a few months following the program, usually within 3 to 6 months. Long-term objectives are usually measured at least one year following the program. The team evaluates impact using community health data. Most often, the nurse and program team use annual epidemiological data or community health assessment data, which is collected at minimum every three years. Benchmarks help determine the impact of programs. For example, in Planning Health Promotion and Disease Prevention Interventions, the nurse and Kenton Hardin County Family Bike Program (KHCFBP) team determined evaluation questions and data techniques from the outcome and impact sections of the logic model. Table 20.7 describes the outcome evaluation of the program. \| Outcome as Stated on the Logic Model \| Evaluation Question \| Data Collection Technique \| \|---\|---\|---\| \| Short term—Increase participant bike safety knowledge post-program \| What was the effect of the KHCFBP on participants’ bike safety knowledge? \| \| \| Short term—Increase participant bike helmet use 30 days post-program \| What was the effect of the KHCFBP on participants’ report of bike helmet use? \| \| \| Short term—Increase participant biking frequency 30 days post-program \| What was the effect of the KHCFBP on participants’ report of bike riding? \| \| \| Long term—Increase incidence of biking in Hardin County over the next 5 years \| Did incidence of bike riding increase in Hardin County? \| \| \| Impact—Increase physical activity of Hardin County residents \| Did physical activity of Hardin County residents increase? \| \| The program team analyzes data after collection. Pre-implementation and post-implementation data are compared. Program evaluation data are also compared to similar program evaluations and national benchmarks. The program team uses this information to evaluate the program’s strengths and weaknesses, determines if it has achieved desired outcomes, and examines its efficacy, effectiveness, and efficiency. The program team develops recommendations regarding the program and shares findings and recommendations with community members and partners. Ongoing evaluation of community health programs is necessary to ensure program success, program continuation, and that community needs are being met.	3,242	common-pile/libretexts_filtered	https://med.libretexts.org/Bookshelves/Nursing/Population_Health_for_Nurses_(OpenStax)/20%3A_Implementation_and_Evaluation_Considerations/20.03%3A_Evaluation_Strategies	libretexts	libretexts-0000.json.gz:1872	https://med.libretexts.org/Bookshelves/Nursing/Population_Health_for_Nurses_(OpenStax)/20%3A_Implementation_and_Evaluation_Considerations/20.03%3A_Evaluation_Strategies
XoY3olj_SY5iyvtf	7.5: Neutron Diffraction	7.5: Neutron Diffraction The first neutron diffraction experiment was in 1945 by Ernest O. Wollan (Figure $\PageIndex{1}$) using the Graphite Reactor at Oak Ridge. Along with Clifford Shull (Figure $\PageIndex{1}$) they outlined the principles of the technique. However, the concept that neutrons would diffract like X-rays was first proposed by Dana Mitchell and Philip Powers. They proposed that neutrons have a wave like structure, which is explained by the de Broglie equation, \ref{1}, where $λ$ is the wavelength of the source usually measured in Å, $h$ is Planck’s constant, $v$ is the velocity of the neutron, and finally $m$ represents the mass of the neutron. \[ \lambda \ =\ h/mv \label{1} \] The great majority of materials that are studied by diffraction methods are composed of crystals. X-rays where the first type of source tested with crystals in order to determine their structural characteristics. Crystals are said to be perfect structures although some of them show defects on their structure. Crystals are composed of atoms, ions or molecules, which are arranged, in a uniform repeating pattern. The basic concept to understand about crystals is that they are composed of an array of points, which are called lattice points, and the motif, which represents the body part of the crystal. Crystals are composed of a series of unit cells. A unit cell is the repeating portion of the crystal. Usually there are another eight unit cells surrounding each unit cell. Unit cells can be categorized as primitive, which have only one lattice point. This means that the unit cell will only have lattice points on the corners of the cell. This point is going to be shared with eight other unit cells. Whereas in a non primitive cell there will also be point in the corners of the cell but in addition there will be lattice points in the faces or the interior of the cell, which similarly will be shared by other cells. The only primitive cell known is the simple crystal system and for nonprimitive cells there are known face-centered cubic, base centered cubic and body centered cubic. Crystals can be categorized depending on the arrangement of lattice points; this will generate different types of shapes. There are known seven crystal systems, which are cubic, tetragonal, orthorhombic, rhombohedral, hexagonal, monoclinic and triclinic. All of these have different angles and the axes are equally the same or different in others. Each of these type of systems have different bravais lattice. Braggs Law Braggs Law was first derived by physicist Sir W.H. Bragg (Figure $\PageIndex{2}$) and his son W. L Bragg (Figure $\PageIndex{3}$) in 1913. It has been used to determine the spacing of planes and angles formed between these planes and the incident beam that had been applied to the crystal examined. Intense scattered X-rays are produced when X-rays with a set wavelength are executed to a crystal. These scattered X-rays will interfere constructively due the equality in the differences between the travel path and the integral number of the wavelength. Since crystals have repeating units patterns, diffraction can be seen in terms of reflection from the planes of the crystals. The incident beam, the diffracted beam and normal plane to diffraction need to lie in the same geometric plane. The angle, which the incident beam forms when it hits the plane of the crystal, is called $2θ$. Figure $\PageIndex{4}$ shows a schematic representation of how the incident beam hits the plane of the crystal and is reflected at the same angle $2θ$, which the incident beam hits. Bragg’s Law is mathematically expressed, \ref{2}: \[ n\lambda = 2d \sin \theta \label{2} \] where $n$ is the integer order of reflection, $λ$= wavelength, and $d$= plane spacing. Bragg’s Law is essential in determining the structure of an unknown crystal. Usually the wavelength is known and the angle of the incident beam can be measured. Having these two known values, the plane spacing of the layer of atoms or ions can be obtained. All reflections collected can be used to determine the structure of the unknown crystal material. Bragg’s Law applies similarly to neutron diffraction. The same relationship is used the only difference being is that instead of using X-rays as the source, neutrons that are ejected and hit the crystal are being examined. Neutron Diffraction Neutrons have been studied for the determination of crystalline structures. The study of materials by neutron radiation has many advantages against the normally used such as X-rays and electrons. Neutrons are scattered by the nucleus of the atoms rather than X-rays, which are scattered by the electrons of the atoms. These generates several differences between them such as that scattering of X-rays highly depend on the atomic number of the atoms whereas neutrons depend on the properties of the nucleus. These lead to a greater and accurately identification of the unknown sample examined if neutron source is being used. The nucleus of every atom and even from isotopes of the same element is completely different. They all have different characteristics, which make neutron diffraction a great technique for identification of materials, which have similar elemental composition. In contrast, X-rays will not give an exact solution if similar characteristics are known between materials. Since the diffraction will be similar for adjacent atoms further analysis needs to be done in order to determine the structure of the unknown. Also, if the sample contains light elements such as hydrogen, it is almost impossible to determine the exact location of each of them just by X-ray diffraction or any other technique. Neutron diffraction can tell the number of light elements and the exact position of them present in the structure. Neutron Inventors Neutrons were first discovered by James Chadwick in 1932 Figure $\PageIndex{5}$ when he showed that there were uncharged particles in the radiation he was using. These particles had a similar mass of the protons but did not have the same characteristics as them. Chadwick followed some of the predictions of Rutherford who first worked in this unknown field. Later, Elsasser designed the first neutron diffraction in 1936 and the ones responsible for the actual constructing were Halban and Preiswerk. This was first constructed for powders but later Mitchell and Powers developed and demonstrated the single crystal system. All experiments realized in early years were developed using radium and beryllium sources. The neutron flux from these was not sufficient for the characterization of materials. Then, years passed and neutron reactors had to be constructed in order to increase the flux of neutrons to be able to realize a complete characterization the material being examined. Between mid and late 40s neutron sources began to appear in countries such as Canada, UK and some other of Europe. Later in 1951 Shull and Wollan presented a paper that discussed the scattering lengths of 60 elements and isotopes, which generated a broad opening of neutron diffraction for the structural information that can be obtained from neutron diffraction. Neutron Sources The first source of neutrons for early experiments was gathered from radium and beryllium sources. The problem with this, as already mentioned, was that the flux was not enough to perform huge experiments such as the determination of the structure of an unknown material. Nuclear reactors started to emerge in early 50s and these had a great impact in the scientific field. In the 1960s neutron reactors were constructed depending on the desired flux required for the production of neutron beams. In USA the first one constructed was the High Flux Beam Reactor (HFBR). Later, this was followed by one at Oak Ridge Laboratory (HFIR) (Figure $\PageIndex{6}$), which also was intended for isotope production and a couple of years later the ILL was built. This last one is the most powerful so far and it was built by collaboration between Germany and France. These nuclear reactors greatly increased the flux and so far there has not been constructed any other better reactor. It has been discussed that probably the best solution to look for greater flux is to look for other approaches for the production of neutrons such as accelerator driven sources. These could greatly increase the flux of neutrons and in addition other possible experiments could be executed. The key point in these devices is spallation, which increases the number of neutrons executed from a single proton and the energy released is minimal. Currently, there are several of these around the world but investigations continue searching for the best approach of the ejection of neutrons. Neutron Detectors Although neutrons are great particles for determining complete structures of materials they have some disadvantages. These particles experiment a reasonably weak scattering when looking especially to soft materials. This is a huge concern because there can be problems associated with the scattering of the particles which can lead to a misunderstanding in the analysis of the structure of the material. Neutrons are particles that have the ability to penetrate through the surface of the material being examined. This is primarily due to the nuclear interaction produced from the particles and the nucleus from the material. This interaction is much greater that the one performed from the electrons, which it is only an electrostatic interaction. Also, it cannot be omitted the interaction that occurs between the electrons and the magnetic moment of the neutrons. All of these interactions discussed are of great advantage for the determination of the structure since neutrons interacts with every single nucleus in the material. The problem comes when the material is being analyzed because neutrons being uncharged materials make them difficult to detect them. For this reason, neutrons need to be reacted in order to generate charged particles, ions. Some of the reactions uusually used for the detection of neutrons are: \[ n\ +\ ^{3}He \rightarrow \ ^{3}H\ +\ ^{1}H\ +\ 0.764 MeV \label{3} \] \[ n\ +\ ^{10}B \rightarrow \ ^{7}Li\ +\ ^{4}He\ +\ \gamma \ +\ 2.3 MeV \label{4} \] \[ n\ +\ ^{6}Li \rightarrow \ ^{4}He\ +\ ^{3}H\ +\ 4.79 MeV \label{5} \] The first two reactions apply when the detection is performed in a gas environment whereas the third one is carried out in a solid. In each of these reaction there is a large cross section, which makes them ideal for neutron capture. The neutron detection hugely depends on the velocity of the particles. As velocity increases, shorter wavelengths are produced and the less efficient the detection becomes. The particles that are executed to the material need to be as close as possible in order to have an accurate signal from the detector. These signal needs to be quickly transduced and the detector should be ready to take the next measurement. In gas detectors the cylinder is filled up with either 3 He or BF 3 . The electrons produced by the secondary ionization interact with the positively charged anode wire. One disadvantage of this detector is that it cannot be attained a desired thickness since it is very difficult to have a fixed thickness with a gas. In contrast, in scintillator detectors since detection is developed in a solid, any thickness can be obtained. The thinner the thickness of the solid the more efficient the results obtained become. Usually the absorber is 6 Li and the substrate, which detects the products, is phosphor, which exhibits luminescence. This emission of light produced from the phosphor results from the excitation of this when the ions pass thorough the scintillator. Then the signal produced is collected and transduced to an electrical signal in order to tell that a neutron has been detected. Neutron Scattering One of the greatest features of neutron scattering is that neutrons are scattered by every single atomic nucleus in the material whereas in X-ray studies, these are scattered by the electron density. In addition, neutron can be scattered by the magnetic moment of the atoms. The intensity of the scattered neutrons will be due to the wavelength at which it is executed from the source. Figure $\PageIndex{7}$ shows how a neutron is scattered by the target when the incident beam hits it. The incident beam encounters the target and the scattered wave produced from the collision is detected by a detector at a defined position given by the angles θ, ϕ which are joined by the dΩ. In this scenario there is assumed that there is no transferred energy between the nucleus of the atoms and the neutron ejected, leads to an elastic scattering. When there is an interest in calculating the diffracted intensities the cross sectional area needs to be separated into scattering and absorption respectively. In relation to the energies of these there is moderately large range for constant scattering cross section. Also, there is a wide range cross sections close to the nuclear resonance. When the energies applied are less than the resonance the scattering length and scattering cross section are moved to the negative side depending on the structure being examined. This means that there is a shift on the scattering, therefore the scattering will not be in a 180° phase. When the energies are higher that resonance it means that the cross section will be asymptotic to the nucleus area. This will be expected for spherical structures. There is also resonance scattering when there are different isotopes because each produce different nuclear energy levels. Coherent and Incoherent Scattering Usually in every material, atoms will be arranged differently. Therefore, neutrons when scattered will be either coherently or incoherently. It is convenient to determine the differential scattering cross section, which is given by \ref{6}, where b represents the mean scattering length of the atoms, k is the scattering vector, r n is the position of the vector of the analyzed atom and lastly N is the total number of atoms in the structure.This equation can be separated in two parts, which one corresponds to the coherent scattering and the incoherent scattering as labeled below. Usually the particles scattered will be coherent which facilitates the solution of the cross section but when there is a difference in the mean scattering length, there will be a complete arrangement of the formula and these new changes (incoherent scattering) should be considered. Incoherent scattering is usually due to the isotopes and nuclear spins of the atoms in the structure. \[ d\sigma /d\Omega \ =\ \|b\|^{2}\ \|\Sigma e^{(ik.r_{n})}\ \|^{2}\ +\ N\|b-b^2\| \label{6} \] Coherent Exp: \[ \|b\|^{2}\ \|\Sigma e^{(ik.r_{n})}\ \|^{2} \nonumber \] Incoherent Exp: \[ N\ \|b-b\|^{2} \nonumber \] The ability to distinguish atoms with similar atomic number or isotopes is proportional to the square of their corresponding scattering lengths. There are already known several coherent scattering lengths of some atoms which are very similar to each other. Therefore, it makes even easier to identify by neutrons the structure of a sample. Also neutrons can find ions of light elements because they can locate very low atomic number elements such as hydrogen. Due to the negative scattering that hydrogen develops it increases the contrast leading to a better identification of it, although it has a very large incoherent scattering which causes electrons to be removed from the incident beam applied. Magnetic Scattering As previously mentioned one of the greatest features about neutron diffraction is that neutrons because of their magnetic moment can interact with either the orbital or the spin magnetic moment of the material examined. Not all every single element in the periodic table can exhibit a magnetic moment. The only elements that show a magnetic moment are those, which have unpaired electrons spins. When neutrons hit the solid this produces a scattering from the magnetic moment vector as well as the scattering vector from the neutron itself. Below Figure $\PageIndex{8}$ shows the different vectors produced when the incident beam hits the solid. When looking at magnetic scattering it needs to be considered the coherent magnetic diffraction peaks where the magnetic contribution to the differential cross section is p 2 q 2 for an unpolarized incident beam. Therefore the magnetic structure amplitude will be given by \ref{9}, where q n is the magnetic interaction vector , p n is the magnetic scattering length and the rest of the terms are used to know the position of the atoms in the unit cell. When this term $F_{mag}$ is squared, the result is the intensity of magnetic contribution from the peak analyzed. This equation only applies to those elements which have atoms that develop a magnetic moment. \[ F_{\text{mag}}\ =\ \Sigma p_{n}q_{n} e^{2\pi i(hx_{n}\ +\ ky_{n}\ +\ Iz_{n})} \label{9} \] Magnetic diffraction becomes very important due to its d-spacing dependence. Due to the greater effect produced from the electrons in magnetic scattering the forward scattering has a greater strength than the backward scattering. There can also be developed similar as in X-ray, interference between the atoms which makes structure factor also be considered. These interference effects could be produced by the wide range in difference between the electron distribution and the wavelength of the thermal neutrons. This factor quickly decreases as compared to X-rays because the beam only interacts with the outer electrons of the atoms. Sample Preparation and Environment In neutron diffraction there is not a unique protocol of factors that should be considered such as temperature, electric field and pressure to name a few. Depending on the type of material and data that has been looked the parameters are assigned. There can be reached very high temperatures such as 1800K or it can go as low as 4K. Usually to get to these extreme temperatures a special furnace capable of reaching these temperatures needs to be used. For example, one of the most common used is the He refrigerator when working with very low temperatures. For high temperatures, there are used furnaces with a heating element cylinder such as vanadium (V), niobium (Nb), tantalum (Ta) or tungsten (W) that is attached to copper bars which hold the sample. Figure $\PageIndex{9}$ shows the design for the vacuum furnaces used for the analysis. The metal that works best at the desired temperature range will be the one chosen as the heating element. The metal that is commonly used is vanadium because it prevents the contribution of other factors such as coherent scattering. Although with this metal this type of scattering is almost completely reduced. Other important factor about this furnaces is that the material been examined should not decompose under vacuum conditions. The crystal needs to be as stable as possible when it is being analyzed. When samples are not able to persist at a vacuum environment, they are heated in the presence of several gases such as nitrogen or argon. Usually in order to prepare the samples that are being examined in neutron diffraction it is needed large crystals rather small ones as the one needed for X-ray studies. This one of the main disadvantages of this instrument. Most experiments are carried out using a four-circle diffractometer. The main reason being is because several experiment are carried out using very low temperatures and in order to achieve a good spectra it is needed the He refrigerator. First, the crystal being analyzed is mounted on a quartz slide, which needs to be a couple millimeters in size. Then, it is inserted into the sample holder, which is chosen depending on the temperatures wanted to be reached. In addition, neutrons can also analyze powder samples and in order to prepare the sample for these they need to be completely rendered into very fine powders and then inserted into the quartz slide similarly to the crystal structures. The main concern with this method is that when samples are grounded into powders the structure of the sample being examined can be altered. Summary Neutron diffraction is a great technique used for complete characterization of molecules involving light elements and also very useful for the ones that have different isotopes in the structure. Due to the fact that neutrons interact with the nucleus of the atoms rather than with the outer electrons of the atoms such as X-rays, it leads to a more reliable data. In addition, due to the magnetic properties of the neutrons there can be characterized magnetic compounds due to the magnetic moment that neutrons develop. There are several disadvantages as well, one of the most critical is that there needs to be a good amount of sample in order to be analyzed by this technique. Also, great amounts of energy are needed to produce large amounts of neutrons. There are several powerful neutron sources that have been developed in order to conduct studies of largest molecules and a smaller quantity of sample. However, there is still the need of devices which can produce a great amount of flux to analyze more sophisticated samples. Neutron diffraction has been widely studied due to the fact that it works together with X-rays studies for the characterization of crystalline samples. The properties and advantages of this technique can greatly increased if some of the disadvantages are solved. For example, the study of molecules which exhibit some type of molecular force can be characterized. This will be because neutrons can precisely locate hydrogen atoms in a sample. Neutrons have gives a better answer to the chemical interactions that are present in every single molecule, whereas X-rays help to give an idea of the macromolecular structure of the samples being examined.	4,611	common-pile/libretexts_filtered	https://chem.libretexts.org/Bookshelves/Analytical_Chemistry/Physical_Methods_in_Chemistry_and_Nano_Science_(Barron)/07%3A_Molecular_and_Solid_State_Structure/7.05%3A_Neutron_Diffraction	libretexts	libretexts-0000.json.gz:20118	https://chem.libretexts.org/Bookshelves/Analytical_Chemistry/Physical_Methods_in_Chemistry_and_Nano_Science_(Barron)/07%3A_Molecular_and_Solid_State_Structure/7.05%3A_Neutron_Diffraction
_8LHya_l2lQDASG9	Learning to be Human Together	What Is a Deliverable? What Have We Delivered? This is a project, generously funded by the Ministry of Colleges and Universities of Ontario and carried out through eCampusOntario’s Virtual Learning Strategies grant program. In the grant we stated: The multi-institutional team will co-design four “living modules” that consider the many nested and entangled functions of the academic ecosystem. Each module will provide learning experiences and supports intended for relevant roles and functions in the academic structure — from students, to educators, services, administration, funders, policymakers, and the larger community. Below you will find the four “living modules” and rich references, further reading, and more. You will also find artifacts that were created over the past year on the project. And you will also find musings about the process of creating a community that collectively did this work. In many ways, the team working on this project feels that the process was the deliverable. Time and again we marveled at how deeply the process had impacted us all. We want to capture some of that here, but please know that you cannot bottle this work up and reproduce it entirely. It does not scale — nor should it. What we can share are suggestions, stories, and experiences for how to do this work. We will also pepper the modules with what we learned along the way and areas we know need more work by us all. This is the journey that defies “completion.” One team member asked, “Do we actually think that humanizing education will happen with four modules?” No, humanizing education will not be accomplished with four modules; the ways that humanizing education will happen is up to each of us and our interactions. Humanizing is fundamentally about relationships, interactions, and experiences with others. Humanizing education is fundamentally relational. A word of warning: we built a community of practice supporting each other in doing this work. We are connected deeply and expect to remain connected beyond the timeline of this work. Humanizing work has this tendency; it brings people together to support, encourage, and challenge each other. One last word of warning: this group has one hell of a sense of humour — perhaps it’s also an essential ingredient to this work. Surround yourself with real people who can laugh at themselves, and then extend that to everyone else. 4 Modules (that will not, in and of themselves, humanize learning) Module 1: Unlearning and Unsettling Questioning and Reflecting Figure 1: Photo by Lukas Juhas on Unsplash Among the domains to be examined are research, evidence, metrics, innovation, ways of knowing and expressing knowledge, value systems, work, intelligence, economics, decision-making, notions of quality, rigour, integrity, efficiency, winning, and trust as they relate to learning. To move forward we must interrogate how we practice now and why. Some of this is the uncomfortable work of unlearning and unsettling. We do this work by embracing questioning and reflecting as we explore the way education is designed (from the physical environment, the virtual environment, the interactional environment, and more). Among the lessons we learn in unlearning and unsettling are the following: - Unbottle-able: we cannot package this work up and make it “scale.” Scale is a word that harkens to the economics of the enterprise, not to the learning outcomes or cultural impacts. We cannot copy and paste modules into different contexts and expect the same results. In fact, we should pause and consider the impact of expecting results at all. Many times, the process is more important than the outcome or any single outcome. - Time to think, time to reflect, slow learning, importance of pauses: when do you take time to explore, wonder, critique, interrogate, question yourself and your own practices, as well as those of others and of institutions? Time and attention are perhaps our most valuable commodity, and it is in short supply. What is lost when we schedule meetings back-to-back and never have a moment to think, digest, let our minds wander to make connections? This is the sawdust of our work. As we cut clean, exact lines we create “waste” in the dust. But what if the dust is the good stuff? What if we accidentally leave something behind in the dust? What if the voices and the people we hope to reach the most with this work fall into the dust? We have to be aware and wary of every cut we make. - Structured structurelessness: in doing this work we acknowledge the need for structure while simultaneously warning that too much structure can curtail curiosity and exploration. So, we advocate for only as much structure as is absolutely necessary for people to have clarity of purpose, but no more. And in that space that is created, we can all consider how things might be. We put education in a straitjacket and then we’re surprised when it isn’t whimsical, innovative, creative, and free. How do we interrogate the usefulness and uselessness of the structure in rubrics, checklists, gatekeeping, rigour, and prerequisites? Module 2: Students as Agents of Their Own Diverse Destiny Vulnerability and Failure Diversity is our society’s most valuable asset. To address current and emerging demands, students must differentiate themselves and continue learning throughout life. This implies rethinking notions of student conformance to singular standards, biased exclusionary recruitment, systems of preferential academic ranking and promotion, reductionist assessment techniques, student surveillance and policing, and winner-takes-all competition, among other academic conventions. How do we equip students to value, develop, and apply their own unique contributions throughout life? - Idolatry — ways to avoid prof-worship: one barrier to student agency is the traditional classroom model, which features the “sage on a stage,” bestowing knowledge on students who are often referred to “bums in seats.” This common understanding removes student agency and knowledge and inflates the status of the professor. Understanding the rigid hierarchical structures of higher education that we are situated within, how do we resist idolatry of those who occupy seats of power? In order to democratize learning and ensure that learners (who on aggregate have a greater range of lived experiences than the professoriate) have agency, we must make conscious effort to avoid worshiping, or contributing to the cult of personality, which oftentimes surrounds professors. - Power is everywhere: make no mistake, where there are people, there is power. And whether or not those with power acknowledge their power, it is there. Human interactions within the realm of all that happens in education is no exception. Policies, practices, conversations, assessments, the ways the classroom are setup … everything can subtly or not so subtly convey power; saying, you belong here, or you do not belong. Module 3: Co-Creating Inclusive Communities Trust and Context While diversity is our greatest asset, inclusion is our most important challenge. The academic mission of advancing learning and discovery, while doing no harm, is best served by an orchestration of diverse perspectives. Current academic processes pit students against students, faculty against faculty, and faculty against students; they create monocultures and biased, exclusionary hierarchies. The academic journey is often a lonely one, especially during the pandemic. How do we create a cohesive learning community out of dissonant and divergent perspectives, deal with conflict, listen to quieter minority voices, give and receive constructive critique, and share knowledge generously for collective benefit? - Community guidelines and participation standards: some groups are publishing participation guidelines or codes of conduct. These can be helpful starting places for a group of people to agree on some standards, but these documents will only be strong if they are visited and revisited and critiqued and modified regularly. You can show your mettle by ensuring this is never a “one-and-done” activity, but rather a value that is embedded in everything you do and how each community member treats each other. - Ethics and social justice: even when you dabble shallowly into humanizing learning, you are confronted almost immediately with issues of social justice and ethics. We argue that this is actually desirable and that change (cultural and therefore educational) will come from communities of practice, practicing this work together and striving to get better and better. - Co-design and co-creation: first, we must start from a point where we acknowledge that power is everywhere. Co-design and co-creation fundamentally challenge and disrupt power. This topic requires much more interrogation and discussion to achieve flattened, co-created works. See more here: Creating Brave Spaces video and “What Is Co-Design?” - Inclusive facilitation Figure 2: Tweet from Ashley Yates regarding facilitation, May 18, 2021, https://twitter.com/brownblaze/status/1394748079090200577 Figure 3: Tweet from Viji Sathy regarding facilitation, October 1, 2021, https://twitter.com/vijisathy/status/1443958751883636736 Module 4: Sustaining Change Critique and Care Figure 4: Photo by Noah Buscher on Unsplash Objective: To spark and sustain equitable system-wide change and adaptation in higher education. Change is hard. Academia, as an institution, was built to resist change and uphold established practices. The flaws in the system — false scarcity, exclusion, rigid hierarchy — are not new, but have been exacerbated throughout the pandemic and demand address. Numerous innovative experiments in more inclusive, future-friendly learning have met insurmountable barriers and failed to thrive. How do we sustain change, complexity, and care in a system that was not designed for what our society currently demands of it? How can we foreground care, hold the gains of learning that we may have made during the strange years of the pandemic, and sustain change? How can we learn the arts of care, critique, and apology in ways that enable us to contribute to the big picture of systemic change without getting derailed by ego? In this module, we’ll return to the liberating structure of what/so what/now what to explore practices of critical inquiry and change-making cycles, even in the face of weariness. We will also frame care as a more reciprocal process than the atomized versions of self-care packaged by our pandemic-era institutional Wellness emails and Wellness Theatre. - Find/address friction points in complex systems - Moving beyond optimizing the past, examining what is evidence, how we interpret rigour and quality, supporting culture change Figure 5: A visualization of the Humanizing Learning co-design schedule from Fall 2021. Drawing by Giulia Forsythe. CC0	2,199	common-pile/pressbooks_filtered	https://ecampusontario.pressbooks.pub/onhumanlearn/chapter/what-is-a-deliverable-what-have-we-delivered/	pressbooks	pressbooks-0000.json.gz:19659	https://ecampusontario.pressbooks.pub/onhumanlearn/chapter/what-is-a-deliverable-what-have-we-delivered/
2ouW3UirTrkr5fSu	Covalent-Network Solids: Semiconductors and Insulators	Covalent-Network Solids: Semiconductors and Insulators Skills to Develop - Explain the properties of some covalent-network solids - Describe semiconductors and some of their properties You can read a quick introduction to covalent-network solids in the intro page. The basic idea is that to make a network of covalent bonds, each atom (or many of the atoms) have to make 3 or 4 bonds to other atoms. This means that covalent-network solids usually include carbon, silicon, and their neighbors in the periodic table. Here, we'll focus on simple, orderly structures like diamond, graphite, and pure silicon. There are also covalent-network solid oxides, like the silicates, in which oxygen atoms connect 2 silicon atoms, and each silicon atom connects to 4 oxygens. Partially covalent oxides are what most rocks and ceramics are made of. Graphite Carbon has 2 allotropes , or pure elemental forms. The more stable form is graphite, a dark, slippery material used in pencils and lubricants. Remember that carbon typically makes 4 bonds. The structure of graphite is flat hexagonal sheets; a single sheet is called graphene . Each carbon atom makes 3 σ bonds and the leftover p orbitals form a delocalized π-bond network over the whole sheet, very similar to the π-bonding in benzene. The π-bond system actually forms bands, like in a metal, allowing graphite to conduct electricity along the sheets. Weak interactions, like London dispersion forces, (called π-stacking in this case) hold the sheets loosely together. Because they can slide past each other (especially when impurity atoms are trapped in between) graphite is a good lubricant. Diamond Structure The other bulk allotrope of carbon is diamond. In diamond, each carbon makes 4 bonds in tetrahedral directions to other carbon atoms. The structure is like the zinc blende ionic structure, except that all the atoms are the same. The properties of diamond (insulator, hard) come from the strong covalent bonds. Remember that C-C bonds are some of the strongest covalent bonds. It's easiest to think about diamond as forming with sp 3 hybrid orbitals on each atom. It's hard to imagine the MO interactions, but the main thing we can know is that because there is good energy match and good overlap between the atoms, the splitting (energy difference) between bonding and anti-bonding MOs will be big (and there won't be any non-bonding MOs, because each atom has 4 orbitals and makes 4 bonds). There will still be bands like in metals, but now there are 2 bands with a big energy gap in the middle. The low-energy, bonding band is called the valence band , and there are exactly enough electrons to fill it. The high-energy, anti-bonding band is called the conduction band , and it is empty. If it was hard to understand the previous paragraph, let's just imagine making 1 bond between 2 atoms. We use one sp 3 hybrid on each atom. These point right at each other, have exactly the same energy, and have good overlap. We can imagine drawing an MO diagram just like for H 2 , with a big energy gap between the bonding and anti-bonding orbitals. Each atom has 4 electrons total, and makes 4 bonds just like this, so each bond gets 1 electron from each atom: just enough to fill up the bonding MO. When we multiply this over all the bonds in the diamond, we get the full valence band and the empty conduction band. The energy gap between them is called the band gap . In diamond, the band gap is big, and so diamond is an insulator. Semiconductors Silicon has a structure just like diamond. (It doesn't make graphite, because mostly π-bonds are weak for the second-row elements.) However, silicon has a smaller band gap than diamond. Germanium, which is below silicon in the periodic table, has the same structure, and an even lower band gap. Generally, as we go down the periodic table, covalent bond strengths get smaller, which is the same as saying that the splitting between bonding and antibonding orbitals gets smaller. It's hard to say why, but if you assume that heavier atoms have worse orbital overlap, you will usually make good predictions. Semiconductors are materials that conduct electricity just a little bit. They are the basis for all computing and electronics. Semiconductivity comes from having a not-quite-full valence band, a not-quite-empty conduction band, or both. If there are a few electrons in the conduction band, they can conduct electricity just like in a metal (except less, because there aren't very many of them!). If there are a few electrons missing from the valence band, the empty spots are called holes and they can move around, also conducting electricity. If the band gap of a material is not too big compared to the thermal energy, then a few electrons can be in the conduction band even though there is room for them in the valence band (because of thermal energy). For this reason, semiconductors conduct better at higher temperature, because more electrons will be in the conduction band. Doping Semiconductors The other way to make a semiconductor, with a material whose band gap is too big at room temperature, is by adding some impurity atoms with different numbers of electrons, which is called doping . Imagine that you have silicon with just a few nitrogen atoms replacing silicon atoms. Each N has an extra electron. Now there will be a few electrons in the conduction band, so it's a semiconductor! And we can control the conductivity by controlling how much N we add. We can do the same thing if we add a little bit of boron, which has 3 electrons. In this case, there would be a few holes in the valence band. These are called p-type (positive, less electrons, like with B) or n-type (negative, extra electrons, like with N) semiconductors. Lots of important devices, like LEDs, solar cells and transistors (the basis of computer chips) are made of layers of p-type and n-type semiconductors. Compound Semiconductors We can also make semiconductors that are compounds, like gallium arsenide (formula GaAs). These have an AB formula, and there are always 8 valence electrons in the formula. For example, Ga has 3 and As has 5, so GaAs has 8. Another example is ZnSe, (Zn has 2 valence electrons in 4s, Se has 6 valence electrons just like O). Thus, they have the same number of valence electrons as C or Si. They also have the same structure (zinc blende, just like diamond except that that atoms alternate types). By combining many different elements, we can change various properties, like band gap, to be exactly what we want. Generally, the band gap increases as the 2 elements are farther apart (the bonding becomes more ionic, and ionic solids aren't conductive). We can even mix 3 or more elements, like in CdZnTe (the actual formula would probably be written (Cd,Zn)Te, meaning that the number of Cd + Zn = Te). To make semiconductors with the right properties, we can use different combinations of elements and also dope with many different elements.	1,536	common-pile/libretexts_filtered	https://chem.libretexts.org/Bookshelves/General_Chemistry/General_Chemistry_Supplement_(Eames)/Solids/Covalent-Network_Solids%3A_Semiconductors_and_Insulators	libretexts	libretexts-0000.json.gz:22937	https://chem.libretexts.org/Bookshelves/General_Chemistry/General_Chemistry_Supplement_(Eames)/Solids/Covalent-Network_Solids%3A_Semiconductors_and_Insulators
-x2bxMXFt5ztR_A4	6.7: Assignment- Employer Branding Overview	6.7: Assignment- Employer Branding Overview Scenario In this module, you learned that recruiting is the art of attraction, and that cultivating a strong employer brand is an essential aspect of that process. Employer branding matters for two primary reasons: it affects an organization’s ability to attract and retain talent and it has labor cost and productivity implications. An ability to cultivate and communicate an engaging employer brand is particularly critical given that it’s a sellers market, with heightened employee expectations and increased competition for a smaller pool of workers. Your Task In your fourth rotation, you are reporting to the firm’s Employer Branding lead. This is a relatively new practice and the team is still developing services and associated deliverables. You have been assigned to develop a proprietary (original) 1-page “How to Build a Strong Brand” overview for clients. Bonus points: submit your deliverable as an infographic (For perspective, search for “how to build an employer brand” and select Images). Refer to Employer Branding for a jump start. Although your how-to must be original (riffing is fine; duplication is not), it should address the following four points: - Step 1: Evaluate your brand. - Step 2: Identify/clarify your employer proposition. - Step 3: Connect with your audience. - Step 4: Recruit & support brand ambassadors. This assignment requires you to incorporate research (cite Harris Poll, Gallup or other credible data) on why a recommendation matters and specific action items associated with each step. Grading Rubric \| Criteria \| Inadequate (40%) \| Minimal (60%) \| Adequate (80%) \| Exemplary (100%) \| Total Points \| \|---\|---\|---\|---\|---\|---\| \| Organization and format \| 2 pts Writing lacks logical organization. It may show some coherence but ideas lack unity. Serious errors and generally is an unorganized format and information. \| 3 pts Writing is coherent and logically organized, using a format suitable for the material presented. Some points may be contextually misplaced and/or stray from the topic. Transitions may be evident but not used throughout the essay. Organization and format used may detract from understanding the material presented. \| 4 pts Writing is coherent and logically organized, using a format suitable for the material presented. Transitions between ideas and paragraphs create coherence. Overall unity of ideas is supported by the format and organization of the material presented. \| 5 pts Writing shows high degree of attention to details and presentation of points. Format used enhances understanding of material presented. Unity clearly leads the reader to the writer’s conclusion and the format and information could be used independently. \| 5 pts \| \| Content \| 8 pts Some but not all required questions are addressed. Content and/or terminology is not properly used or referenced. Little or no original thought is present in the writing. Concepts presented are merely restated from the source, or ideas presented do not follow the logic and reasoning presented throughout the writing. \| 12 pts All required questions are addressed but may not be addressed with thoughtful consideration and/or may not reflect proper use of content terminology or additional original thought. Additional concepts may not be present and/or may not be properly cited sources. \| 16 pts All required questions are addressed with thoughtful consideration reflecting both proper use of content terminology and additional original thought. Some additional concepts may be presented from other properly cited sources, or originated by the author following logic and reasoning they’ve clearly presented throughout the writing. \| 20 pts All required questions are addressed with thoughtful in-depth consideration reflecting both proper use of content terminology and additional original thought. Additional concepts are clearly presented from properly cited sources, or originated by the author following logic and reasoning they’ve clearly presented throughout the writing. \| 20 pts \| \| Development—Critical Thinking \| 8 pts Shows some thinking and reasoning but most ideas are underdeveloped, unoriginal, and/or do not address the questions asked. Conclusions drawn may be unsupported, illogical or merely the author’s opinion with no supporting evidence presented. \| 12 pts Content indicates thinking and reasoning applied with original thought on a few ideas, but may repeat information provided and/ or does not address all of the questions asked. The author presents no original ideas, or ideas do not follow clear logic and reasoning. The evidence presented may not support conclusions drawn. \| 16 pts Content indicates original thinking, cohesive conclusions, and developed ideas with sufficient and firm evidence. Clearly addresses all of the questions or requirements asked. The evidence presented supports conclusions drawn. \| 20 pts Content indicates synthesis of ideas, in-depth analysis and evidence beyond the questions or requirements asked. Original thought supports the topic, and is clearly a well-constructed response to the questions asked. The evidence presented makes a compelling case for any conclusions drawn. \| 20 pts \| \| Grammar, Mechanics, Style \| 2 pts Writing contains many spelling, punctuation, and grammatical errors, making it difficult for the reader to follow ideas clearly. There may be sentence fragments and run-ons. The style of writing, tone, and use of rhetorical devices disrupts the content. Additional information may be presented but in an unsuitable style, detracting from its understanding. \| 3 pts Some spelling, punctuation, and grammatical errors are present, interrupting the reader from following the ideas presented clearly. There may be sentence fragments and run-ons. The style of writing, tone, and use of rhetorical devices may detract from the content. Additional information may be presented, but in a style of writing that does not support understanding of the content. \| 4 pts Writing is free of most spelling, punctuation, and grammatical errors, allowing the reader to follow ideas clearly. There are no sentence fragments and run-ons. The style of writing, tone, and use of rhetorical devices enhance the content. Additional information is presented in a cohesive style that supports understanding of the content. \| 5 pts Writing is free of all spelling, punctuation, and grammatical errors and written in a style that enhances the reader’s ability to follow ideas clearly. There are no sentence fragments and run-ons. The style of writing, tone, and use of rhetorical devices enhance the content. Additional information is presented to encourage and enhance understanding of the content. \| 5 pts \| \| Total: \| 50 pts \|	1,349	common-pile/libretexts_filtered	https://biz.libretexts.org/Courses/Lumen_Learning/Human_Resources_Management_(Lumen)/06%3A_Recruitment_and_Selection/6.07%3A_Assignment-Employer_Branding_Overview	libretexts	libretexts-0000.json.gz:16211	https://biz.libretexts.org/Courses/Lumen_Learning/Human_Resources_Management_(Lumen)/06%3A_Recruitment_and_Selection/6.07%3A_Assignment-Employer_Branding_Overview
TGK3hzDvHHAPqSFB	General Chemistry - Lecture & Lab	79 Introduction to Gases Gases Outline - Gas Pressure - Relating Pressure, Volume, Amount, and Temperature: The Ideal Gas Law - Stoichiometry of Gaseous Substances, Mixtures, and Reactions - Effusion and Diffusion of Gases - The Kinetic-Molecular Theory - Non-Ideal Gas Behavior <!–?cnx.eoc class=”key-equations” title=”Key-Equations”?–><!–?cnx.eoc class=”summary” title=”Chapter Summary”?–><!–?cnx.eoc class=”exercises” title=”Exercises”?–><!–?cnx.eoc class=”references” title=”References”?–> We are surrounded by an ocean of gas—the atmosphere—and many of the properties of gases are familiar to us from our daily activities. Heated gases expand, which can make a hot air balloon rise (Figure 1) or cause a blowout in a bicycle tire left in the sun on a hot day. Gases have played an important part in the development of chemistry. In the seventeenth and eighteenth centuries, many scientists investigated gas behavior, providing the first mathematical descriptions of the behavior of matter. In this chapter, we will examine the relationships between gas temperature, pressure, amount, and volume. We will study a simple theoretical model and use it to analyze the experimental behavior of gases. The results of these analyses will show us the limitations of the theory and how to improve on it.	243	common-pile/pressbooks_filtered	https://library.achievingthedream.org/sanjacgeneralchemistry/chapter/introduction-to-gases/	pressbooks	pressbooks-0000.json.gz:64245	https://library.achievingthedream.org/sanjacgeneralchemistry/chapter/introduction-to-gases/
qDkzALs-c3PjIMvg	Introduction to Criminology	15. Crimes of the Powerful 15.1 Crimes of the Powerful are White-Collar Crimes Michael Brandt, MA The idea that heads of corporations, the military, or leaders of countries (or those that work closely with them) can actually be criminals (and in some cases, killers) may seem outrageous. I recall discussing former U.S. president George W. Bush’s decision to invade Iraq in 2003 with an acquaintance. Declared illegal by then U.N. Secretary General Kofi Annan, Bush’s decision resulted in widespread injury and death (MacAskill & Borger, 2004). I suggested the large number of deaths in the context of an illegal invasion made the U.S. president a serial killer just like Robert Pickton. Someone nearby overheard our conversation and became outraged. They could not believe I was “making a moral equivalence” between the actions of a U.S. president and a serial killer. I actually said what the president of the United States did was arguably morally worse than what Pickton did, based on the number of people killed: Bush’s invasion, it is estimated, resulted in the deaths of 288,000 people, mostly civilians (Iraq Body Count, n.d). The death toll attributed to Pickton: 49 (CBC/Radio Canada, 2007). Government actions, not the actions of individuals acting alone, are responsible, by far, for most injury and death on the planet. Indeed, wars resulted in over 350 million deaths in the 20th century alone (Friedrichs, 2007). The actions of corporations in their pursuit of profit have led to injuries and death that far exceed those associated with the “crime problem” as commonly understood. And the actions of senior members of the military have resulted in widespread fraud and the inability to account for trillions of dollars in spending (Michigan State University, 2017). Despite often being ignored, there is overwhelming evidence that: [b]y every possible measure—money wasted, property destroyed, lives ruined, people killed—the affluent are more dangerous than the poor. Authorities wreak more havoc than their subjects. The “average” Canadian is more likely to suffer at the hands of government, elected and appointed officials, business organizations, [or] professionals […] than from all the street thugs, youth gangs, home invaders, illegal (im)migrants, pot growers and squeegee kids that our society can produce. (Menzies, Chunn, & Boyd, 2001, p. 13) Criminologists use a variety of terms to describe such “crimes of the powerful,” each referring to a subset of harmful conduct. The most widely known term, white-collar crime, was originally defined by American criminologist Edwin Sutherland as, “a crime committed by a person of respectability and high social status in the course of his occupation” (Sutherland, 1983, p. 7, emphasis added). The important feature of white-collar crime is that the individual is able to use their occupational position and socio-economic status to commit their offence and avoid detection. Sutherland (1983) focused on the most senior occupational positions — business managers and executives — as they possess the power to cause the most harm. Sutherland (1983) excluded powerful people’s crimes that are not connected to their occupational role. Thus, a corporate executive convicted of killing his spouse would be guilty of murder, a crime, but not a white-collar crime. He included within his definition of white-collar crime regulatory offences as well as civil offences, as he saw no reason to segregate harms that can cause as much (or even more) harm from those acts officially designated as crimes. Including these noncriminal offences has caused some to replace the term white-collar crime with the concept of white-collar deviance (Thio et al., 2013, p. 365). This chapter focusses on several types of harmful behaviour including the traditional forms of white-collar crime, occupational crime and corporate crime — as well as other forms of white-collar crime, including financial crime, political crime, and the form of crime responsible for most human suffering, injury, and death: state-organised crime. a crime committed by a person of respectability and high social status in the course of their occupation. in contrast to criminal offences, where the state initiates the proceedings against a criminal defendant, civil offences are initiated by a private citizen (or corporation) against a person (or corporation). Those found guilty in a civil proceeding are said to be liable for “damages”. Rather than prison, they pay the victim money.	913	common-pile/pressbooks_filtered	https://kpu.pressbooks.pub/introcrim/chapter/15-1-crimes-of-the-powerful-are-white-collar-crimes/	pressbooks	pressbooks-0000.json.gz:65093	https://kpu.pressbooks.pub/introcrim/chapter/15-1-crimes-of-the-powerful-are-white-collar-crimes/
_HtxD2jNlOakt5W4	3.3: Slope of a Line	3.3: Slope of a Line By the end of this section, you will be able to: - Find the slope of a line - Graph a line given a point and the slope - Graph a line using its slope and intercept - Choose the most convenient method to graph a line - Graph and interpret applications of slope–intercept - Use slopes to identify parallel and perpendicular lines Before you get started, take this readiness quiz. Find the Slope of a Line When you graph linear equations, you may notice that some lines tilt up as they go from left to right and some lines tilt down. Some lines are very steep and some lines are flatter. In mathematics, the measure of the steepness of a line is called the slope of the line. The concept of slope has many applications in the real world. In construction the pitch of a roof, the slant of the plumbing pipes, and the steepness of the stairs are all applications of slope. and as you ski or jog down a hill, you definitely experience slope. We can assign a numerical value to the slope of a line by finding the ratio of the rise and run. The rise is the amount the vertical distance changes while the run measures the horizontal change, as shown in this illustration. Slope is a rate of change. See Figure . The slope of a line is $m=\frac{\text{rise}}{\text{run}}$. The rise measures the vertical change and the run measures the horizontal change. To find the slope of a line, we locate two points on the line whose coordinates are integers. Then we sketch a right triangle where the two points are vertices and one side is horizontal and one side is vertical. To find the slope of the line, we measure the distance along the vertical and horizontal sides of the triangle. The vertical distance is called the rise and the horizontal distance is called the run , - Locate two points on the line whose coordinates are integers. - Starting with one point, sketch a right triangle, going from the first point to the second point. - Count the rise and the run on the legs of the triangle. - Take the ratio of rise to run to find the slope: $m=\frac{\text{rise}}{\text{run}}$. Find the slope of the line shown. Solution \| Locate two points on the graph whose coordinates are integers. \| $(0,5)$ and $(3,3)$ \| \| Starting at $(0,5)$, sketch a right triangle to $(3,3)$ as shown in this graph. \| \| \| Count the rise— since it goes down, it is negative. \| The rise is $−2$. \| \| Count the run. \| The run is 3. \| \| Use the slope formula. \| $m=\frac{\text{rise}}{\text{run}}$ \| \| Substitute the values of the rise and run. \| $m=\frac{-2}{3}$ \| \| Simplify. \| $m=−\frac{2}{3}$ \| \| The slope of the line is $−\frac{2}{3}$. \| \| \| So y decreases by 2 units as x increases by 3 units. \| Find the slope of the line shown. - Answer - $-\frac{4}{3}$ Find the slope of the line shown. - Answer - $-\frac{3}{5}$ How do we find the slope of horizontal and vertical lines? To find the slope of the horizontal line, $y=4$, we could graph the line, find two points on it, and count the rise and the run. Let’s see what happens when we do this, as shown in the graph below. $ \begin{array} {ll} {\text{What is the rise?}} &{\text{The rise is }0.} \\ {\text{What is the run?}} &{\text{The run is }3.} \\ {\text{What is the slope?}} &{m=\frac{\text{rise}}{\text{run}}} \\ {} &{m=\frac{0}{3}} \\ {} &{m=0} \\{}&{\text{The slope of the horizontal line } y=4 \text{ is }0.} \\ \end{array} \nonumber$ Let’s also consider a vertical line, the line $x=3$, as shown in the graph. $ \begin{array} {ll} {\text{What is the rise?}} &{\text{The rise is }2.} \\ {\text{What is the run?}} &{\text{The run is }0.} \\ {\text{What is the slope?}} &{m=\frac{\text{rise}}{\text{run}}} \\ {} &{m=\frac{2}{0}} \\ \end{array} \nonumber$ The slope is undefined since division by zero is undefined. So we say that the slope of the vertical line $x=3$ is undefined. All horizontal lines have slope 0. When the y -coordinates are the same, the rise is 0. The slope of any vertical line is undefined. When the x -coordinates of a line are all the same, the run is 0. The slope of a horizontal line, $y=b$, is 0. The slope of a vertical line, $x=a$, is undefined. Find the slope of each line: a. $x=8$ b. $y=−5$. Solution- $x=8$ This is a vertical line. Its slope is undefined. - $y=−5$ This is a horizontal line. It has slope 0. Find the slope of the line: $x=−4$. - Answer - undefined Find the slope of the line: $y=7$. - Answer - 0 Sometimes we’ll need to find the slope of a line between two points when we don’t have a graph to count out the rise and the run. We could plot the points on grid paper, then count out the rise and the run, but as we’ll see, there is a way to find the slope without graphing. Before we get to it, we need to introduce some algebraic notation. We have seen that an ordered pair $(x,y)$ gives the coordinates of a point. But when we work with slopes, we use two points. How can the same symbol $(x,y)$ be used to represent two different points? Mathematicians use subscripts to distinguish the points. $ \begin{array} {ll} {(x_1, y_1)} &{\text{read “} x \text{ sub } 1, \space y \text{ sub } 1 \text{”}} \\ {(x_2, y_2)} &{\text{read “} x \text{ sub } 2, \space y \text{ sub } 2 \text{”}} \\ \end{array} \nonumber$ We will use $(x_1,y_1)$ to identify the first point and $(x_2,y_2)$ to identify the second point. If we had more than two points, we could use $(x_3,y_3)$, $(x_4,y_4)$, and so on. Let’s see how the rise and run relate to the coordinates of the two points by taking another look at the slope of the line between the points $(2,3)$ and $(7,6)$, as shown in this graph. \( \begin{array} {ll} {\text{Since we have two points, we will use subscript notation.}} &{ \begin{pmatrix} x_1, & y_1 \\ 2 & 3 \end{pmatrix} \begin{pmatrix} x_2, & y_2 \\ 7 & 6 \end{pmatrix}} \\ {} &{m=\frac{\text{rise}}{\text{run}}} \\ {\text{On the graph, we counted the rise of 3 and the run of 5.}} &{m=\frac{3}{5}} \\ {\text{Notice that the rise of 3 can be found by subtracting the}} &{} \\ {y\text{-coordinates, 6 and 3, and the run of 5 can be found by}} &{} \\ {\text{subtracting the x-coordinates 7 and 2.}} &{} \\ {\text{We rewrite the rise and run by putting in the coordinates.}} &{m=\frac{6-3}{7-2}} \\ {} &{} \\ {\text{But 6 is } y_2 \text{, the y-coordinate of the second point and 3 is }y_1 \text{, the y-coordinate}} &{} \\ {\text{of the first point. So we can rewrite the slope using subscript notation.}} &{m=\frac{y_2-y_1}{7-2}} \\ {\text{Also 7 is the x-coordinate of the second point and 2 is the x-coordinate}} &{} \\ {\text{of the first point. So again we rewrite the slope using subscript notation.}} &{m=\frac{y_2-y_1}{x_2-x_1}} \\ \end{array} \nonumber\) We’ve shown that $m=\frac{y_2−y_1}{x_2−x_1}$ is really another version of $m=\frac{\text{rise}}{\text{run}}$. We can use this formula to find the slope of a line when we have two points on the line. The slope of the line between two points $(x_1,y_1)$ and $(x_2,y_2)$ is: $m=\frac{y_2−y_1}{x_2−x_1}$. The slope is: \[y\text{ of the second point minus }y\text{ of the first point} \nonumber\] \[\text{over} \nonumber\] \[x\text{ of the second point minus }x\text{ of the first point} \nonumber\] Use the slope formula to find the slope of the line through the points $(−2,−3)$ and $(-7,4)$ . Solution$ \begin{array} {ll} {\text{We’ll call (−2,−3) point #1and (−7,4) point #2.}} &{ \begin{pmatrix} x_1, & y_1 \\ -2 & -3 \end{pmatrix} \begin{pmatrix} x_2, & y_2 \\ -7 & 4 \end{pmatrix}} \\ {\text{Use the slope formula.}} &{m=\frac{y_2-y_1}{x_2-x_1}} \\ {\text{Substitute the values.}} &{} \\ {\text{y of the second point minus y of the first point}} &{} \\ {\text{x of the second point minus x of the first point}} &{m=\frac{4-(-3)}{-7-(-2)}} \\{\text{Simplify}}&{m=\frac{7}{-5}} \\ {} &{m=\frac{-7}{5}} \\ \end{array} \nonumber$ Let’s verify this slope on the graph shown. \[m=\frac{\text{rise}}{\text{run}} \nonumber\] \[m=\frac{7}{−5} \nonumber\] \[m=\frac{−7}{5} \nonumber\] Use the slope formula to find the slope of the line through the pair of points: $(−3,4)$ and $(2,−1)$. - Answer - $-1$ Use the slope formula to find the slope of the line through the pair of points: $(−2,6)$ and $(−3,−4)$. - Answer - 10 Graph a Line Given a Point and the Slope Up to now, in this chapter, we have graphed lines by plotting points, by using intercepts, and by recognizing horizontal and vertical lines. We can also graph a line when we know one point and the slope of the line. We will start by plotting the point and then use the definition of slope to draw the graph of the line. Graph the line passing through the point $(1,−1)$ whose slope is $m=\frac{3}{4}$. Solution\| Step 1. Plot the given point. \| Plot $ (1, -1) $ \| \| \| Step 2. Use the slope formula $ m=\dfrac{\text{rise}}{\text{run}} $ to identify the rise and the run. \| Identify the rise and the run. \| $ m = \dfrac{3}{4} \\ $ $ \dfrac{\text{rise}}{\text{run}} = \dfrac{3}{4} \\ $ rise = 3 run = 4 \| \| Step 3. Starting at the given point, count out the rise and run to mark the second point. \| Start at $ (1, -1) $ and count the rise and the run. Up $3$ units, right $4$ units. \| \| \| Step 4. Connect the points with a line. \| Connect the two points with a line. \| You can check your work by finding a third point. Since the slope is $m=\frac{3}{4}$, it can also be written as $m=\frac{−3}{−4}$ (negative divided by negative is positive!). Go back to $(1,−1)$ and count out the rise, $−3$, and the run, $−4$. Graph the line passing through the point $(2,−2)$ with the slope $m=\frac{4}{3}$. - Answer - Graph the line passing through the point $(−2,3)$ with the slope $m=\frac{1}{4}$. - Answer - - Plot the given point. - Use the slope formula $m=\frac{\text{rise}}{\text{run}}$ to identify the rise and the run. - Starting at the given point, count out the rise and run to mark the second point. - Connect the points with a line. Graph a Line Using its Slope and Intercept We have graphed linear equations by plotting points, using intercepts, recognizing horizontal and vertical lines, and using one point and the slope of the line. Once we see how an equation in slope–intercept form and its graph are related, we’ll have one more method we can use to graph lines. See Figure . Let’s look at the graph of the equation $y=12x+3$ and find its slope and y -intercept. The red lines in the graph show us the rise is 1 and the run is 2. Substituting into the slope formula: \[m=\frac{\text{rise}}{\text{run}} \nonumber\] \[m=\frac{1}{2} \nonumber\] The y -intercept is $(0,3)$. Look at the equation of this line. $y = {\color{red}{\dfrac{1}{2}}}x+{\color{Cerulean}{3}} $ Look at the slope and y -intercept. slope $ m = {\color{red}{\dfrac{1}{2}}} $ and y-intercept $ (0, {\color{Cerulean}{3}} ) $ When a linear equation is solved for y , the coefficient of the x term is the slope and the constant term is the y -coordinate of the y -intercept. We say that the equation $y=\frac{1}{2}x+3$ is in slope–intercept form. Sometimes the slope–intercept form is called the “ y -form.” The slope–intercept form of an equation of a line with slope m and y -intercept, $(0,b)$ is $y=mx+b$. Let’s practice finding the values of the slope and y -intercept from the equation of a line. Identify the slope and y -intercept of the line from the equation: a. $y=−\frac{4}{7}x−2$ b. $x+3y=9$ Solutiona. We compare our equation to the slope–intercept form of the equation. \| Write the slope–intercept form of the equation of the line. \| $ y = {\color{red}{m}}x + \color{Cerulean}{b} $ \| \| Write the equation of the line. \| $ y = {\color{red}{-\dfrac{4}{7}}}x \color{Cerulean}{-2} $ \| \| Identify the slope. \| $ m = {\color{red}{-\dfrac{4}{7}}} $ \| \| Identify the y -intercept. \| y=intercept is $ (0, {\color{Cerulean}{-2}} ) $ \| b. When an equation of a line is not given in slope–intercept form, our first step will be to solve the equation for y . \| Solve for y . \| $x+3y=9$ \| \| Subtract x from each side. \| $ 3y = -x + 9 $ \| \| Divide both sides by 3. \| $ \dfrac{3y}{3} = \dfrac{-x + 9}{3} $ \| \| Simplify. \| $y = -\dfrac{1}{3}x+3 $ \| \| Write the slope–intercept form of the equation of the line. \| $ y = {\color{red}{m}}x + \color{Cerulean}{b} $ \| \| Write the equation of the line. \| $ y = {\color{red}{-\dfrac{1}{3}}}x + \color{Cerulean}{3} $ \| \| Identify the slope. \| $ m = {\color{red}{-\dfrac{1}{3}}} $ \| \| Identify the y -intercept. \| y=intercept is $ (0, {\color{Cerulean}{3}} ) $ \| Identify the slope and y -intercept from the equation of the line. a. $y=\frac{2}{5}x−1$ b. $x+4y=8$ - Answer - - $m=\frac{2}{5}$; $(0,−1)$ - $m=−\frac{1}{4}$; $(0,2)$ Identify the slope and y -intercept from the equation of the line. a. $y=−\frac{4}{3} x+1$ b. $3x+2y=12$ - Answer - - $m=−\frac{4}{3}$; $(0,1)$ - $m=−\frac{3}{2}$; $(0,6)$ We have graphed a line using the slope and a point. Now that we know how to find the slope and y -intercept of a line from its equation, we can use the y -intercept as the point, and then count out the slope from there. Graph the line of the equation $y=−x+4$ using its slope and y -intercept. Solution\| $y=mx+b$ \| \| \| The equation is in slope–intercept form. \| $y=−x+4$ \| \| Identify the slope and y -intercept. \| $m=−1$ y -intercept is $(0,4)$ \| \| Plot the y -intercept. \| See the graph. \| \| Identify the rise over the run. \| $m=\frac{−1}{1}$ \| \| Count out the rise and run to mark the second point. \| rise $-1$, run $1$ \| Draw the line as shown in the graph. Graph the line of the equation $y=−x−3$ using its slope and y -intercept. - Answer - Graph the line of the equation $y=−x−1$ using its slope and y -intercept. - Answer - Now that we have graphed lines by using the slope and y -intercept, let’s summarize all the methods we have used to graph lines. Choose the Most Convenient Method to Graph a Line Now that we have seen several methods we can use to graph lines, how do we know which method to use for a given equation? While we could plot points, use the slope–intercept form, or find the intercepts for any equation, if we recognize the most convenient way to graph a certain type of equation, our work will be easier. Generally, plotting points is not the most efficient way to graph a line. Let’s look for some patterns to help determine the most convenient method to graph a line. Here are five equations we graphed in this chapter, and the method we used to graph each of them. \[ \begin{array} {lll} {} &{\textbf{Equation}} &{\textbf{Method}} \\ {\text{#1}} &{x=2} &{\text{Vertical line}} \\ {\text{#2}} &{y=−1} &{\text{Horizontal line}} \\ {\text{#3}} &{−x+2y=6} &{\text{Intercepts}} \\ {\text{#4}} &{4x−3y=12} &{\text{Intercepts}} \\ {\text{#5}} &{y=−x+4} &{\text{Slope–intercept}} \\ \end{array} \nonumber\] Equations #1 and #2 each have just one variable. Remember, in equations of this form the value of that one variable is constant; it does not depend on the value of the other variable. Equations of this form have graphs that are vertical or horizontal lines. In equations #3 and #4, both x and y are on the same side of the equation. These two equations are of the form $Ax+By=C$. We substituted $y=0$ to find the x - intercept and $x=0$ to find the y -intercept, and then found a third point by choosing another value for x or y . Equation #5 is written in slope–intercept form. After identifying the slope and y- intercept from the equation we used them to graph the line. This leads to the following strategy. Consider the form of the equation. - If it only has one variable, it is a vertical or horizontal line. - $x=a$ is a vertical line passing through the x -axis at a . - $y=b$ is a horizontal line passing through the y -axis at b . - If y is isolated on one side of the equation, in the form $y=mx+b$, graph by using the slope and y -intercept. - Identify the slope and y -intercept and then graph. - If the equation is of the form $Ax+By=C$, find the intercepts. - Find the x - and y -intercepts, a third point, and then graph. Determine the most convenient method to graph each line: ⓐ $y=5$ ⓑ $4x−5y=20$ ⓒ $x=−3$ ⓓ $y=−\frac{5}{9}x+8$ - Answer - ⓐ $y=5$ This equation has only one variable, y . Its graph is a horizontal line crossing the y -axis at $5$. ⓑ $4x−5y=20$ This equation is of the form $Ax+By=C$. The easiest way to graph it will be to find the intercepts and one more point. ⓒ $x=−3$ There is only one variable, x . The graph is a vertical line crossing the x -axis at $−3$. ⓓ $y=−\frac{5}{9}x+8$ Since this equation is in $y=mx+b$ form, it will be easiest to graph this line by using the slope and y -intercepts. Determine the most convenient method to graph each line: ⓐ $3x+2y=12$ ⓑ $y=4$ ⓒ $y=\frac{1}{5}x−4$ ⓓ $x=−7$. - Answer - ⓐ intercepts ⓑ horizontal line ⓒ slope-intercept ⓓ vertical line Determine the most convenient method to graph each line: ⓐ $x=6$ ⓑ $y=−\frac{3}{4}x+1$ ⓒ $y=−8$ ⓓ $4x−3y=−1$. - Answer - ⓐ vertical line ⓑ slope-intercept ⓒ horizontal line ⓓ intercepts Graph and Interpret Applications of Slope-Intercept Many real-world applications are modeled by linear equations. We will take a look at a few applications here so you can see how equations written in slope-intercept form relate to real-world situations. Usually, when a linear equation models uses real-world data, different letters are used for the variables, instead of using only x and y . The variable names remind us of what quantities are being measured. Also, we often will need to extend the axes in our rectangular coordinate system to bigger positive and negative numbers to accommodate the data in the application. The equation $F=\frac{9}{5}C+32$ is used to convert temperatures, C, on the Celsius scale to temperatures, F , on the Fahrenheit scale. ⓐ Find the Fahrenheit temperature for a Celsius temperature of 0. ⓑ Find the Fahrenheit temperature for a Celsius temperature of 20. ⓒ Interpret the slope and F -intercept of the equation. ⓓ Graph the equation. - Answer - ⓐ $ \begin{array} {ll} {\text{Find the Fahrenheit temperature for a Celsius temperature of 0.}} &{F=\frac{9}{5}C+32} \\ {\text{Find F when C=0.}} &{F=\frac{9}{5}(0)+32} \\ {\text{Simplify.}} &{F=32} \\ \end{array} \nonumber$ ⓑ $ \begin{array} {ll} {\text{Find the Fahrenheit temperature for a Celsius temperature of 20.}} &{F=\frac{9}{5}C+32} \\ {\text{Find F when C=20.}} &{F=\frac{9}{5}(20)+32} \\ {\text{Simplify.}} &{F=36+32} \\ {\text{Simplify.}} &{F=68} \\ \end{array} \nonumber$ ⓒ Interpret the slope and F -intercept of the equation. Even though this equation uses F and C , it is still in slope-intercept form.The slope, $\frac{9}{5}$, means that the temperature Fahrenheit ( F ) increases 9 degrees when the temperature Celsius ( C ) increases 5 degrees. The F -intercept means that when the temperature is $0°$ on the Celsius scale, it is $32°$ on the Fahrenheit scale. ⓓ Graph the equation. We’ll need to use a larger scale than our usual. Start at the F -intercept $(0,32)$, and then count out the rise of 9 and the run of 5 to get a second point as shown in the graph. The equation $ h =2s+50$ is used to estimate a woman’s height in inches, h , based on her shoe size, s . ⓐ Estimate the height of a child who wears women’s shoe size 0. ⓑ Estimate the height of a woman with shoe size 8. ⓒ Interpret the slope and h -intercept of the equation. ⓓ Graph the equation. - Answer - ⓐ 50 inches ⓑ 66 inches ⓒ The slope, 2, means that the height, h , increases by 2 inches when the shoe size, s , increases by 1. The h -intercept means that when the shoe size is 0, the height is 50 inches. ⓓ The equation $ T =\frac{ 1}{4}n +40$ is used to estimate the temperature in degrees Fahrenheit, T , based on the number of cricket chirps, n , in one minute. ⓐ Estimate the temperature when there are no chirps. ⓑ Estimate the temperature when the number of chirps in one minute is 100. ⓒ Interpret the slope and T -intercept of the equation. ⓓ Graph the equation. - Answer - ⓐ 40 degrees ⓑ 65 degrees ⓒ The slope, $\frac{1}{4}$, means that the temperature Fahrenheit ( F ) increases 1 degree when the number of chirps, n , increases by 4. The T -intercept means that when the number of chirps is 0, the temperature is 40°. ⓓ The cost of running some types business have two components—a fixed cost and a variable cost . The fixed cost is always the same regardless of how many units are produced. This is the cost of rent, insurance, equipment, advertising, and other items that must be paid regularly. The variable cost depends on the number of units produced. It is for the material and labor needed to produce each item. Sam drives a delivery van. The equation $C=0.5m+60$ models the relation between his weekly cost, C , in dollars and the number of miles, m , that he drives. ⓐ Find Sam’s cost for a week when he drives 0 miles. ⓑ Find the cost for a week when he drives 250 miles. ⓒ Interpret the slope and C -intercept of the equation. ⓓ Graph the equation. - Answer - ⓐ $ \begin{array} {ll} {\text{Find Sam’s cost for a week when he drives 0 miles.}} &{C=0.5m+60} \\ {\text{Find C when m=0.}} &{C=0.5(0)+60} \\ {\text{Simplify.}} &{C=60} \\ {} &{\text{Sam’s costs are }$\text{60 when he drives 0 miles.}} \\ \end{array} \nonumber $ ⓑ $ \begin{array} {ll} {\text{Find Sam’s cost for a week when he drives 250 miles.}} &{C=0.5m+60} \\ {\text{Find C when m=250.}} &{C=0.5(250)+60} \\ {\text{Simplify.}} &{C=185} \\ {} &{\text{Sam’s costs are }$\text{185 when he drives 250 miles.}} \\ \end{array} \nonumber $ ⓒ Interpret the slope and C -intercept of the equation.The slope, 0.5, means that the weekly cost, C , increases by $0.50 when the number of miles driven, n, increases by 1. The C -intercept means that when the number of miles driven is 0, the weekly cost is $60. ⓓ Graph the equation. We’ll need to use a larger scale than our usual. Start at the C -intercept $(0,60)$.To count out the slope $m= 0.5$, we rewrite it as an equivalent fraction that will make our graphing easier. $ \begin{array} {ll} {} &{m=0.5} \\ {\text{Rewrite as a fraction.}} &{m=\frac{0.5}{1}} \\ {\text{Multiply numerator and}} &{} \\ {\text{denominator by 100}} &{m=\frac{0.5(100)}{1(100)}} \\ {\text{Simplify.}} &{m=\frac{50}{100}} \\ \end{array} \nonumber $ So to graph the next point go up 50 from the intercept of 60 and then to the right 100. The second point will be $(100, 110)$. Stella has a home business selling gourmet pizzas. The equation $C=4p+25$ models the relation between her weekly cost, C , in dollars and the number of pizzas, p , that she sells. ⓐ Find Stella’s cost for a week when she sells no pizzas. ⓑ Find the cost for a week when she sells 15 pizzas. ⓒ Interpret the slope and C -intercept of the equation. ⓓ Graph the equation. - Answer - ⓐ $25 ⓑ $85 ⓒ The slope, 4, means that the weekly cost, C , increases by $4 when the number of pizzas sold, p, increases by 1. The C -intercept means that when the number of pizzas sold is 0, the weekly cost is $25. ⓓ Loreen has a calligraphy business. The equation $C=1.8n+35$ models the relation between her weekly cost, C , in dollars and the number of wedding invitations, n , that she writes. ⓐ Find Loreen’s cost for a week when she writes no invitations. ⓑ Find the cost for a week when she writes 75 invitations. ⓒ Interpret the slope and C -intercept of the equation. ⓓ Graph the equation. - Answer - ⓐ $35 ⓑ $170 ⓒ The slope, $1.8$, means that the weekly cost, C , increases by $$1.80$ when the number of invitations, n , increases by 1. The C -intercept means that when the number of invitations is 0, the weekly cost is $35. ⓓ Use Slopes to Identify Parallel and Perpendicular Lines Two lines that have the same slope are called parallel lines . Parallel lines have the same steepness and never intersect. We say this more formally in terms of the rectangular coordinate system. Two lines that have the same slope and different y -intercepts are called parallel lines. See Figure . Verify that both lines have the same slope, $m=\frac{2}{5}$, and different y -intercepts. What about vertical lines? The slope of a vertical line is undefined, so vertical lines don’t fit in the definition above. We say that vertical lines that have different x -intercepts are parallel, like the lines shown in this graph. Parallel lines are lines in the same plane that do not intersect. - Parallel lines have the same slope and different y -intercepts. - If $m1$ and $m2$ are the slopes of two parallel lines then $m1=m2$. - Parallel vertical lines have different x -intercepts Since parallel lines have the same slope and different y -intercepts, we can now just look at the slope–intercept form of the equations of lines and decide if the lines are parallel. Use slopes and y -intercepts to determine if the lines are parallel: ⓐ $3x−2y=6$ and $y=\frac{3}{2}x+1$ ⓑ $y=2x−3$ and $−6x+3y=−9$. - Answer - ⓐ $ \begin{array} {llll} {} &{3x−2y=6} &{\text{and}} &{y=\frac{3}{2}x+1} \\ {} &{−2y=−3x+6} &{} &{} \\ {\text{Solve the first equation for y.}} &{\frac{-2y}{-2}=\frac{-3x+6}{-2}} &{} &{} \\ {\text{The equation is now in slope–intercept form.}} &{y=\frac{3}{2}x−3} &{} &{} \\ {\text{The equation of the second line is already}} &{} &{} &{} \\ {\text{in slope–intercept form.}} &{} &{} &{y=\frac{3}{2}x+1} \\ {} &{} &{} &{} \\ {} &{y=\frac{3}{2}x−3} &{} &{y=\frac{3}{2}x+1} \\ {Identify the slope andy-intercept of both lines.} &{y=mx+b} &{} &{y=mx+b} \\ {} &{m=\frac{3}{2}} &{} &{y=\frac{3}{2}} \\ {} &{\text{y-intercept is }(0,−3)} &{} &{\text{y-intercept is }(0,1)} \\ \end{array} \nonumber$ The lines have the same slope and different y -intercepts and so they are parallel. You may want to graph the lines to confirm whether they are parallel. ⓑ $ \begin{array} {llll} {} &{y=2x−3} &{\text{and}} &{−6x+3y=−9} \\ {\text{The first equation is already in slope–intercept form.}} &{y=2x−3} &{} &{} \\ {} &{} &{} &{−6x+3y=−9} \\ {} &{} &{} &{3y=6x−9} \\ {\text{Solve the second equation for y.}} &{} &{} &{\frac{3y}{3}=\frac{6x−9}{3}} \\ {} &{} &{} &{y=2x−3} \\ {\text{The second equation is now in slope–intercept form.}} &{} &{} &{y=2x−3} \\ {} &{} &{} &{} \\ {} &{y=2x−3} &{} &{y=2x−3} \\ {\text{Identify the slope andy-intercept of both lines.}} &{y=mx+b} &{} &{y=mx+b} \\ {} &{m=2} &{} &{m=2} \\ {} &{\text{y-intercept is }(0,−3)} &{} &{\text{y-intercept is }(0,-3)} \\ \end{array} \nonumber$ The lines have the same slope, but they also have the same y -intercepts. Their equations represent the same line and we say the lines are coincident. They are not parallel; they are the same line. Use slopes and y- intercepts to determine if the lines are parallel: ⓐ $2x+5y=5$ and $y=−\frac{2}{5}x−4$ ⓑ $y=−\frac{1}{2}x−1$ and $x+2y=−2$. - Answer - ⓐ parallel ⓑ not parallel; same line Use slopes and y- intercepts to determine if the lines are parallel: ⓐ $4x−3y=6$ and $y=\frac{4}{3}x−1$ ⓑ $y=\frac{3}{4}x−3$ and $3x−4y=12$. - Answer - ⓐ parallel ⓑ not parallel; same line Use slopes and y- intercepts to determine if the lines are parallel: ⓐ $y=−4$ and $y=3$ ⓑ $x=−2$ and $x=−5$. - Answer - ⓐ $y=−4$ and $y=3$ We recognize right away from the equations that these are horizontal lines, and so we know their slopes are both 0. Since the horizontal lines cross the y -axis at y=−4y=−4 and at y=3,y=3, we know the y -intercepts are (0,−4)(0,−4) and (0,3).(0,3). The lines have the same slope and different y -intercepts and so they are parallel.ⓑ $x=−2$ and $x=−5$ We recognize right away from the equations that these are vertical lines, and so we know their slopes are undefined. Since the vertical lines cross the x -axis at $x=−2$ and $x=−5$, we know the y -intercepts are $(−2,0)$ and $(−5,0)$. The lines are vertical and have different x -intercepts and so they are parallel. Use slopes and y- intercepts to determine if the lines are parallel: ⓐ $y=8$ and $y=−6$ ⓑ $x=1$ and $x=−5$. - Answer - ⓐ parallel ⓑ parallel Use slopes and y- intercepts to determine if the lines are parallel: ⓐ $y=1$ and $y=−5$ ⓑ $x=8$ and $x=−6$. - Answer - ⓐ parallel ⓑ parallel Let’s look at the lines whose equations are $y=\frac{1}{4}x−1$ and $y=−4x+2$, shown in Figure . These lines lie in the same plane and intersect in right angles. We call these lines perpendicular. If we look at the slope of the first line, $m_1=\frac{1}{4}$, and the slope of the second line, $m_2=−4$, we can see that they are negative reciprocals of each other. If we multiply them, their product is $−1$. \[\begin{array} {l} {m_1·m_2} \\ {14(−4)} \\ {−1} \\ \end{array} \nonumber\] This is always true for perpendicular lines and leads us to this definition. Perpendicular lines are lines in the same plane that form a right angle. - If $m_1$ and $m_2$ are the slopes of two perpendicular lines, then: - their slopes are negative reciprocals of each other, $m_1=−\frac{1}{m_2}$. - the product of their slopes is $−1$, $m_1·m_2=−1$. - A vertical line and a horizontal line are always perpendicular to each other We were able to look at the slope–intercept form of linear equations and determine whether or not the lines were parallel. We can do the same thing for perpendicular lines. We find the slope–intercept form of the equation, and then see if the slopes are opposite reciprocals. If the product of the slopes is $−1$, the lines are perpendicular. Use slopes to determine if the lines are perpendicular: ⓐ $y=−5x−4$ and $x−5y=5$ ⓑ $7x+2y=3$ and $2x+7y=5$ - Answer - ⓐ The first equation is in slope–intercept form.Solve the second equation fory.Identify the slope of each line.y=−5x−4yym1=−5x−4=mx+b=−5x−5y−5y−5y−5y=5=−x+5=−x+5−5=15x−1yym2=15x−1=mx+b=15The first equation is in slope–intercept form.y=−5x−4Solve the second equation fory.x−5y=5−5y=−x+5−5y−5=−x+5−5y=15x−1Identify the slope of each line.y=−5x−4y=mx+bm1=−5y=15x−1y=mx+bm2=15 The slopes are negative reciprocals of each other, so the lines are perpendicular. We check by multiplying the slopes, Since −5(15)=−1,−5(15)=−1, it checks. ⓑ Solve the equations fory.Identify the slope of each line.7x+2y2y2y2y=3=−7x+3=−7x+32=−72x+32ym1=mx+b=−722x+7y7y7y7y=5=−2x+5=−2x+57=−27x+57ym1=mx+b=−27Solve the equations fory.7x+2y=32y=−7x+32y2=−7x+32y=−72x+322x+7y=57y=−2x+57y7=−2x+57y=−27x+57Identify the slope of each line.y=mx+bm1=−72y=mx+bm1=−27 The slopes are reciprocals of each other, but they have the same sign. Since they are not negative reciprocals, the lines are not perpendicular. Use slopes to determine if the lines are perpendicular: ⓐ $y=−3x+2$ and $x−3y=4$ ⓑ $5x+4y=1$ and $4x+5y=3$. - Answer - ⓐ perpendicular ⓑ not perpendicular Use slopes to determine if the lines are perpendicular: ⓐ $y=2x−5$ and $x+2y=−6$ ⓑ $2x−9y=3$ and $9x−2y=1$. - Answer - ⓐ perpendicular ⓑ not perpendicular Key Concepts - Slope of a Line - The slope of a line is $m=\frac{\text{rise}}{\text{run}}$. - The rise measures the vertical change and the run measures the horizontal change. - How to find the slope of a line from its graph using $m=\frac{\text{rise}}{\text{run}}$. - Locate two points on the line whose coordinates are integers. - Starting with one point, sketch a right triangle, going from the first point to the second point. - Count the rise and the run on the legs of the triangle. - Take the ratio of rise to run to find the slope: $m=\frac{\text{rise}}{\text{run}}$. - Slope of a line between two points. - The slope of the line between two points $(x_1,y_1)$ and $(x_2,y_2)$ is: \[m=\frac{y_2−y_1}{x_2−x_1} \nonumber\]. - The slope of the line between two points $(x_1,y_1)$ and $(x_2,y_2)$ is: - How to graph a line given a point and the slope. - Plot the given point. - Use the slope formula $m=\frac{\text{rise}}{\text{run}}$ to identify the rise and the run. - Starting at the given point, count out the rise and run to mark the second point. - Connect the points with a line. - Slope Intercept Form of an Equation of a Line - The slope–intercept form of an equation of a line with slope m and y -intercept, $(0,b)$ is $y=mx+b$ - Parallel Lines - Parallel lines are lines in the same plane that do not intersect. Parallel lines have the same slope and different y -intercepts. If $m_1$ and $m_2$ are the slopes of two parallel lines then $m_1=m_2$. Parallel vertical lines have different x -intercepts. - Parallel lines are lines in the same plane that do not intersect. - Perpendicular Lines - Perpendicular lines are lines in the same plane that form a right angle. - If $m_1$ and $m_2$ are the slopes of two perpendicular lines, then: their slopes are negative reciprocals of each other, $m_1=−\frac{1}{m_2}$. the product of their slopes is $−1$, $m_1·m_2=−1$. - A vertical line and a horizontal line are always perpendicular to each other. Glossary - parallel lines - Parallel lines are lines in the same plane that do not intersect. - perpendicular lines - Perpendicular lines are lines in the same plane that form a right angle.	7,281	common-pile/libretexts_filtered	https://math.libretexts.org/Bookshelves/Algebra/Intermediate_Algebra_1e_(OpenStax)/03%3A_Graphs_and_Functions/3.03%3A_Slope_of_a_Line	libretexts	libretexts-0000.json.gz:4765	https://math.libretexts.org/Bookshelves/Algebra/Intermediate_Algebra_1e_(OpenStax)/03%3A_Graphs_and_Functions/3.03%3A_Slope_of_a_Line
zzOp3Wh3gnTWAPD3	Comet lore: Halley's comet in history and astronomy, by Edwin Emerson.	Warning with thy portentous train Of earthquake, plague and battle-plain? Some say that thou dost never fail To bring some evil in tl.y tail. in Europe, in far China. They have known for certain that this Comet would come; and they knew just when and where in the Heavens the Comet would first show itself to the naked eye — down to the very night. Comet has been seen by the people of this earth before. It came and went seventy-four years ago. Seventy-six years before that, it came and went. And seventy-six years before that, the Comet had come and gone. As long as human beings have lived on this earth — for thousands and thousands of years — human eyes have beheld this same Comet every seventy-six years or so. written down records of this Comet. Long, long ago, when white men were still savages who dwelt in caves, patient star-gazers in China and Chaldea studied the motions of this Comet. hundred and twenty-eight years ago, when this Comet was seen shining over the City of London, the great astronomer, Edmund Halley, made a special study of it. Halley was the first to say that this Comet had come before and would surely come again. He wrote down the time when the Comet would come again, long after he should be dead. "If it should return," he wrote, "according to our predictions, about the year 1758, impartial posterity will not refuse to acknowledge that this was first discovered by an Englishman." The Comet returned, as he had foretold, seventeen years after Halley's death, when it was first seen in 1758, on Christmas night, by a man in Saxony, named Palitsch, who was looking for the Comet. Even night by night on that prodigious Blaze, That hairy Comet, that long streaming Star, Which threatens Earth with Famine, Plague and War?" "Nation shall rise against nation, and kingdom against kingdom; and great earthquakes shall be in divers places, and famines and pestilences; and fearful sights and great signs shall there be from Heaven." "There was seen another sign in Heaven, and behold a great red dragon . . . and his tail draweth a third part of the stars in Heaven. And behold the third woe cometh quickly." (Chap. XII., Verse 14.) David beheld a Comet in the shape of a flaming sword: "And David lifted up his eyes and saw the angel of the Lord stand between the earth and the Heaven, having a drawn sword in his hand stretched out over Jerusalem." Unterrified, and as a Comet burned That fired the length of Ophiuchus huge In th' arctic sky, and from its horrid hair, Shakes pestilence and war." The Great Deluge, described in Holy Writ, came after the appearance of a mighty Comet (Halley's Comet), so Dr. William Whiston, Sir Isaac Newton's successor in the Lucasian chair of Mathematics at Cambridge, set forth in a special treatise. The great French astronomer, Laplace, also reached the same conclusion. This same Comet (Halley's Comet) likewise foretold the final fall of the Holy City, Jerusalem, in the year 76 after Christ. This Comet was seen by St. Peter. Josephus in his History of the Jewish Wars recorded the nightly appearance of this Comet over the City of Jerusalem just before the war which ended with the destruction of the Holy City. "Amongst other warnings," writes Josephus, who saw this Comet with his own eyes, ua Comet of the kind called swordshaped, because their tails appear to represent the blade of a sword, was seen above the city for the space of a whole year." Josephus at the time rebuked his Jewish countrymen for listening to false prophets while so clear a sign from Heaven was before their very eyes. This same Comet (Halley's Comet) reappeared at a critical period of the rule of Constantine the Great, the first Christian Emperor of Rome. He first beheld his sign from Heaven in the midst of battle as it blazed overhead in the sign of a Cross. With the help of his mother, the sainted Helen, Constantine was moved thereby to turn Christian. Constantinople, the great capital of the Orient, which owes its name to this same Emperor Constantine, was lost to Christendom in the year 1453, when the Turks overran the great city with fire and sword. This event, it is recorded, was heralded by another appearance of a Comet. Three years later, when the Turks were about to descend upon Belgrade, another Comet (Halley's Comet) spread consternation throughout Europe. At that time Pope Calixtus III., on the appearance of this Comet, seeing that evils were impending for the human race, called for prayers that the Almighty would tian faith. At the same time the Holy Father gave orders for all Church bells to be tolled at noon to remind faithful Christians to pray for those battling against the Turk. Since that time in most Catholic countries the Angelus is still regularly rung at noon. In Italy, even to-day, the cakes sold before the church doors at noon go by the name of Comete. Comets are to be taken as signs from Heaven. Baeda, the Venerable, declared in the seventh century in England, that "Comets portend revolutions of kingdoms, pestilence, war, winds, or heat." to the baleful influence of Comets. The ancient year books of China, written centuries before white men kept any records, tell of the appearance of Comets and of the disasters they foretold. meant war. The woe of one Comet (Halley's Comet of i456)> which had the shape of a Turkish scimitar, so the Arab soothsayers foretold, would be turned against their enemies. This was the same Comet which brought such fear to the hearts of Pope Calixtus III. and all his Christian followers. On the night of Caesar's assassination, when the Comet was seen blazing at its brightest, the Romans said that it had come to bear away the great soul of the murde Caesar. , At the death of Nero, the Roman Emperor, who persecuted the Christians, a Comet blazed forth again The Roman historian Suetonius, who wrote the Life of peror Nero, thus described this Comet : "A blazing star, which was commonly held to portend destruction to Kings and Princes, reappeared above the Horizon several nights in succession." Another great Comet (Halley's again) reappeared when Attila, the King of the Huns, the ''Scourge of God," was overthrown in the greatest battle of Christendom on the Catalaunian fields. "Qual con le chiome sanguinose horrende Splender Cometa suol per 1'aria adusta, Che i regni muta, e i feri morbi adduce, Ai purpurei tiranni infausta luce." — Gerusalemme Liber ata, Canto Vll., Stanza 52. And even the like precurse of fierce events, As harbingers preceding still the fates And prologue to the omen coming on." loosely dispersed in the wind: "All as a blazing starre doth farre outcast His heavy beames, and flaming lockes dispredd, At sight whereof the people stand aghast; But the sage Wizzard telles, as he has redd, That it importunes death and doleful drearyhedd." John Milton, besides likening Satan to a Comet, as before quoted, also showed that he shared in the belief that the flaming swords mentioned in Holy Writ were Comets : of the Comet: "Hast thou ne'er seen the Comet's flaming light? Th' illustrious stranger passing, terror sheds On gazing Nations, from his fiery train." The poets of other nations have written of Comets in like vein. There is an old German rhyme, sung by German school children even to-day, which has been put into English by Dr. Andrew D. White in his "History of the Doctrine of Comets" : "Eight things there be a Comet brings, When it on high doth horrid range; Wind, Famine, Plague, and Death to Kings, War, Earthquake, Floods and Direful Change." This little rhyme was originally put forth for German school children by two Protestant preachers of Basle, Switzerland, at the time of the great Comet of 1618, which heralded the outbreak of the great "Thirty Years' War." These Protestant ministers got their belief in Comets and their evil influence upon mankind not from the Church of Rome, but from the Bible teachings of such great Protestant reformers as Martin Luther, Melanchthon, Zwingli, Calvin, John Knox of Scotland, Bishop Jeremy Taylor and John Howe, the great Nonconformist divine. Heaven. . The great divines of the Church of England, — from Cranmer, Bishop Latimer, Archbishops Spottiswoode and Bramhall, Bishop Jeremy Taylor, down to our own times, clearly preached the doctrine that Comets must be taken as tokens from Heaven. Thus the Comet of 1572 was pointed out from the pulpits of England and Scotland as a token of Heaven's wrath and warning at the St. Batholomew Massacre on the night of August 24, 1572, when thirty thousand Huguenots were murdered in the streets of Paris and elsewhere in France. Across the sea, in the new Commonwealth of Massachusetts, the great New England divine and President of Harvard College, Increase Mather, on the apparition of the great Comet now known as Halley's, in 1682, preached on "Heaven's Wrath Alarm to the World — wherein is shown that fearful sights and signs in the Heavens are the presages of great calamities at hand." Increase Mather preached on the text taken from the Book of Revelation : "And the third Angel sounded, and there fell a great Star burning as a Torch, . . and behold the Third Woe cometh quickly." In this sermon the great preacher told of the Roman Emperor Vespasian, who, when warned of the omen of a Comet, made fun of it, and then died miserably. So Mather preached: "For the Lord hath fired his beacon in the Heavens among the stars of God there. The fearful sign is not yet out of sight. . . Do we not see the sword blazing over us? . . Doth God threaten The profound Russian thinker Tolstoy, in his great book "War and Peace," has written of the flaming Comet of 1811. This was the famous "Comet of Napoleon," which blazed over Western Europe when Napoleon was gathering his grand army for its disastrous march into Russia and to Moscow. At Moscow, the ancient capital of Russia, this Comet was observed by anxious thousands. One night there was this talk between a novice nun and the Abbess of her Convent. On their way to vesper service one evening in Moscow the nun suddenly beheld the Comet for the first time and asked: "What is that star?" Shortly after this the bloody battle of Borodino was fought, and Napoleon, with his army, appeared before the gates of Moscow. The hundred-towered city was abandoned by the Russians and was given over to the flames. "Every night the Comet blazed in the Heavens, and we all asked ourselves: What misfortune does it bring? Then the enemy came, and our sacred city was put to the torch. Our convent, together with all other cloisters, monasteries and churches, was burned to the ground." All this has been fully set forth by the famous French astronomer Messier, a latter day observer of Halley's Comet, who wrote a special book on "The Wonderful Comet which appeared at the Birth of Napoleon the Great." As for the many Comets that have blazed down upon other great conquerors and other bloody wars, before the comparatively recent Comets of the American Civil War and the Napoleonic Wars, they are all set down in a special History of Comets. In this great work, entitled UA History of All Comets," the Latin scholar Lubienitius has pointed out all the calamities and dire events which attended the appearance of each and every Comet recorded in history. THE EFFECTS OF COMETS ON MAN SOME thinkers have pointed out that there has often been a direct connection between the feelings produced in the human soul by the appearance of a Comet and the human deeds of violence or the human epidemics and excessive mortality following the widespread terror produced by Comets. Only this year (1910) the appearance I of Inness' Comet over Mexico caused a panic stricken holy pilgrimage to the Shrine of Talpa. In China, too, it caused terror, resulting in Christian massacres. \| plagues connected with Comets. Thus Ambroise Pare, the "Father of French Surgery," who flourished in the sixteenth century, has recorded the effect produced upon his contemporaries by the Comet of 1528. "This Comet was so horrible," wrote Dr. Pare, "so frightful, and it produced such great terror among the common people, that many died of fear and many others fell sick." Dr. Pare himself appears to have come under the influence of this fear, judging from his awe-struck description of the appearance of this Comet: "It appeared to be of excessive length; and was of the colour of blood. At the summit of it was seen the figure of a bent arm, holding in its hand a great sword as if about to strike. "At the end of the point there were three stars. On both sides of the rays of this Comet were seen a great number of axes, knives, and , blood-coloured swords, among which were a great number of hideous human faces with beards and bristling hair." Emperor Charles V., of Germany and Spain, the monarch who boasted that "the sun never set on his dominions," was so moved by the appearance of a Comet in 1556, that he gave up his crown and became a monk. Certain metaphysicians have held that there is a substance in a Comet, or in its tail, which has a weird effect on man's brain, as moonshine is believed to have on some men, making them lunatics. As a matter of fact, as Arago pointed out, Comets have caused tremendous spring tides just like the moon. The same irresistible pull of gravity or electricity or light-pressure must perforce affect other substances besides water, such as human brains. According to this metaphysical theory, the close approach of a Comet to the earth affects and disturbs men's brains, so that men are inwardly stirred with warlike impulses. Hence the great wars almost invariably following the appearance of Comets. Hence, too, the appeal to Comets made by so many conquerors, from William the Conqueror down to Napoleon. In the homely phrase of one writer, "the inner eye of man, under the weird effect of a Comet, sees red and makes him thirst for blood." Those rare beings who have lying latent within them the gift of Second Sight or divination, according to this same metaphysical theory, upon the near approach of Comets find themselves stirred to prophesy. Hence, so many marvellous prophesies inspired by Comets since the ancient days of Merlin, the seer. "THE COMET OF 1910 SO ALARMED THE PEOPLE OF MEXICO THAT MANY THOUSANDS WENT ON A HOLY PILGRIMAGE TO THE SHRINE OF TALPA IN XALISCO."— Mexican Herald. memorable prophesies. On January 2Oth the French astrologer and prophetess Madame de Thebes, who predicted the disastrous French floods of this year, as well as the coming of Inness' unexpected Comet, uttered the following prophesies: trembling. "The earth is under a terrific strain from Comets and planetary revolutions. Human destiny is red. That means blood. Political events are black. Terrible changes are imminent. "This winter, France will be swept by terrible floods. Paris will be under water. The influence of form changes in other planets and the coming of a Comet will affect us for the worse. "The strain of the stars will be most severely felt in America. The people of America will have to pay dearly for all their riches and sudden prosperity. With the coming of another Comet disaster will descend upon America. "A financial crash is impending, to be followed by a long string of suicides. Black ruling us, men will commit all manner of crimes and knaveries for money. "The times are swaying toward degeneration. We are swinging within the evil influence of a strange orbit. Our souls are jarred from their proper bearings. I Soon after this prophesy was uttered came the first of such suicides. Adam Toma, a wealthy landowner of Szozona, Hungary, cut his throat because of the Comet. He left a note saying that the Comet was the cause of his death. Cardinal Gibbons later expressed his profound belief that the Paris floods of this year were sent by God as a punishment to the Parisians for their frivolities and sins, of which the Comet was a fiery warning. Commenting on Madame de Thebes' predictions and her connection of the Comet of 1910 with this year's spring-floods in France, Italy and Germany, the French astronomer Henri Deslandres, late Director of the Astronomical Observatory of Meudon and member of the French Academy of Sciences, said: "However distant Comets may be, it is not at all impossible that their enormous tails, measuring 75,000,000 to 125,000,000 miles in length, may come in contact with our atmosphere. The theory that a Comet may disturb the atmosphere of the earth, causing rains of great duration, and consequently inundations and the sudden overflow of rivers, is not at all absurd. It can be sustained by scientific reasoning." Comet. Before Madame de Thebes' ominous prophesy concerning Halley's Comet and its effects upon America were cabled over to this country, another, no less dire prediction of financial disaster in the United States, coincident with the appearance of Halley's Comet, was made by W. E. Corey, the President of the American Steel Trust. AT GREENWICH. Mr. Corey then warned his friends to "call in their money and get from under" because a calamitous financial crash and general business ruin would surely come during the Spring of 1910. The most ominous of all prophesies connected with the coming of Halley's Comet this year was made by the venerable General Ballington Booth, the head of the Salvation Army. Speaking in London, immediately after Halley's Comet had been located, early this year, General Booth said: "We are, this year, rapidly approaching the end of all things, with similar results, but far surpassing in horors any disaster that has gone before. "All things will be wound up. Besides a deluge of water sweeping parts of the world and its inhabitants there will be fierce destruction by fire." All Comets recorded in history, so Lubieninitius has shown in his "Universal History of All Comets," appeared in connection with some great event or catastrophe in the History of Man. George F. Chambers, one of the most up-to-date writers on Astronomy and Comets, on the second page of his "Story of the Comets" (1909), declares: "It is the general testimony of History during many hundreds of years, one might even say during fully 2',ooo years, that Comets were always considered to be peculiarly 'ominous of the wrath of Heaven and as harbingers of wars and famines, of the dethronement of Monarchs and the dissolution of Empires/ ' Reaching back into remotest history, the sacred books of India show that the births of Krishna and of Buddha were foretold by moving lights in the Heavens. The ancient records of China tell of the appearance of a moving beacon in Heaven at the birth of YU, the first ruler of the Celestial Empire, and again at the birth of the great Chinese prophet, Lao-Tse. The ancient Greeks have recorded similar appearances of Comets. Aesculapius, the divine healer and first physician, was born under a Comet. Another moving star with long radiant gleams of light streaming behind it shone forth at the birth of Moses. This Comet was seen by the Magi of Egypt, who pointed it out to the King as an omen meant for him. Hence Pharaoh's order, as recorded in the Old Testament, for the slaughter of all male Jewish infants then born in Egypt HISTORIC COMETS IN ANTIQUITY T^HE earliest Comet of which there is any historic record was a Comet mentioned in the oldest cuneiform inscriptions of Babylonia several thousand years before our Christian era, recently found on the north bank of Nahr-al-Kalb, near Beyrut in Syria. This Comet is recorded to have been visible to the naked eye for 29 nights. At the time Lubienitius wrote his big "History of all the Comets" the exact date of this Comet had not been fixed. Lubienitus, though, had a record of this same Comet, the date of which he fixes at the year 2312 before Christ, the date computed by him and other writers for the beginning of the deluge. the great Deluge. Two hundred and eighty-eight years after the great Deluge, according to the records of the Chaldean star gazers, there appeared another Comet. This is the date, computed by Lubienitius, for the building of the Tower of Babel and the confusion of tongues. Two thousand and sixty-four years before Christ, another Comet appeared, as recorded by the Chaldeans. This is the date given for the birth of Abraham. When Abraham was seventy years old, in the year 1949 B. C., a Comet was seen shining over the Valley of Siddim for twenty-two nights. This is the date given by Bible historians for the destruction of Sodom and of Siddim. Jewish analists record a Comet in Egypt in the year corresponding to B. C. 1841. This Comet shone at the time of the bitter persecution of the Jews by the Egyptians. Arabian star gazers have recorded a Comet shining over Arabia 1732 B. C. In that year there was a terrible famine, of which mention is made in the Old Testament. The ancient Chinese year books record the appearance of a Comet over northern China and Manchuria in the year corresponding to 1537 B. C. The appearance of the Comet, so the Chinese chronicles tell, was followed by a great flood and disastrous famine. of the Jews from Egypt. In the year B. C. 1194, we are told by Hyginus that "On the fall of Troy, one of the Pleiades group of stars rushed along the Heavens toward the Arctic pole, where the star remained visible with dishevelled hair, to which the name of Comet is applied." We are informed by Pliny, the Roman historian, that in B. C. 975, the "Egyptians and Ethiopians suffered from a terrible famine, the dire effects of a Comet. It appeared all on fire, and was twisted in the form of a wreath, and had a hideous aspect. It seemed not to be a star, but rather a knot of fire." Babylonian cuneiform inscriptions tell us that about 575 B. C., when Nebuchadnezzar overran Elam, ua star arose whose head was bright as day, while from its luminous body a tail extended like the sting of a scorpion." sea fight of Salamis. The next Comet mentioned by Lubienitius appeared in B. C. 466, when it was seen for 75 nights all over Greece. I:i that year Greece was ravaged by war between the Spartans and Athenians, and the city of Sparta was all but destroyed by an earthquake. The next Comet appeared one generation later in 431 B. C., and was seen through 60 nights all over the ancient world. This Comet was followed by a terrible pestilence which swept over Aethiopia, Egypt, Athens, and Rome. War broke out all over Greece. It was the beginning of the great Peloponnesian War, which devastated Greece for a generation to follow. In the year 394 B. C., there was another Comet seen in Greece, followed by the great Corinthian War with the bloody battles of Knidus and Koronea. Aristotle records a Comet seen by him in his fifteenth year, 371 B. C. The sight of it inspired the youth to a special study of astronomy. The Comet .was visible until the end of the first week of July. On July eighth was fought the great battle between the Thebans and Spartans, when Epaminondas, one of the greatest generals of antiquity, overthrew the Spartans. The next Comet, that of 338 B. C., which was likewise observed by Aristotle, who had then become the teacher of Alexander the Great, marked Alexander's first public entry into the history of the world. The Comet blazed its brightest on the eve of the bloody battle of Chaeronea, Alexander's first victory and achievement in war. In the year 344 B. C., there was another Comet, followed by another war in Greece and Sicily. Diodorus of Sicily wrote of this Comet: "On the departure of the expedition of Timoleon from Corinth for Sicily with all his war ships, the Gods foretold success by an extraordinary prodigy: A burning torch appeared in the Heavens for an entire night and went before the fleet into Sicily." The Comets of Carthage. Nearly a hundred years passed before the appearance of another Comet in 240 B. C. This is the first recorded appearance of Halley's Comet. By the light of this Comet, Hamilcar, the great Carthaginian general, made his young son Hannibal swear eternal enmity to the Romans. Hamilcar was then in the midst of preparations for the war against Rome, which broke out soon afterward. Comets appear to have been stars of special omen to Hannibal and to his native city, Carthage. Twenty years later, appeared another Comet which shone over Carthage for 22 nights. Its appearance was followed by the outbreak of the great war between Hannibal and the Romans, and by a terrible earthquake in Greece. The next Comet shone in 204 B. C., when Hannibal suffered his first bloody defeat by Sempronius, while Scipio, Hannibal's arch enemy, was crossing over to Africa, for the first attack upon Carthage. The appearance of the next Comet, twenty years later, 184 B. C., which shone through 88 nights over Asia Minor "with a horrible lustre" was followed by the death of Hannibal. Soothsayers at the court of King Prusias of Bithynia, in Asia Minor, whither Hannibal had fled from the Romans, told the King that the Comet betokened Hannibal's early death. This so wrought on Hannibal's spirit that he ended his life with poison. horrible size." It was seen for many nights running all over the Mediterranean Sea. Its appearance was followed by the outbreak of the third great Punic War between Rome and Carthage. Within four years another Comet, blazing over northern Africa in 146 B. C., was followed by the fall of Carthage, which was stormed and utterly destroyed by the Romans. Mithridates, King of Pontus, and conqueror of Asia Minor, another arch foe of the Romans, having been born under a Comet, seems to have fallen under the bane of Comets. During the Winter of 134-135 B. C., preceding Mithridates* birth, a Comet of unusual lustre flared over Asia Minor through 72 days. This Comet was so bright that its long, flaming tail was plainly visible even in day time. The ancient historian Justinus thus described it: "Its splendour eclipsed that of the midday sun and occupied the fourth part of Heaven." 119 B. C. Mithridates' fourth Comet, now identified as Halley's Comet, was seen over Asia Minor through the Winter months of 87-88 B. C., just before the horrible massacre of 150,000 Italians ordered by Mithridates. . Twenty-five years later, 63 B. C., Mithridates saw his Comet for the last time when his own son rose up in arms against him. The omen of the Comet so wrought on Mithridates that he first poisoned himself and then had one of his own soldiers despatch him with his sword. No other Comet is recorded in ancient history during this century, except the one which was seen shining over Italy preceding the birth (July n, 100 B. C.) of Julius Caesar, destined to become "The foremost man of all this world," as Shakespeare calls him. "Caesar's Comet" as it came to be known (now identified as Halley's Comet) appeared again over Italy during the great Civil War between Marius and Sylla, when Caesar was first entering into public affairs and earned his spurs as a warrior. "Caesar's Comet" shone again over Rome in the year 60 B. C., when Julius Caesar, together with Pompey and Crassus, took charge of the government of Rome and presently seized supreme power as Consul of Rome. Ten years later "Caesar's Comet" was seen once more in Italy in the Winter months of 49-50 B. C., when Caesar, returning from his conquest of Gaul, crossed the Rubicon and began the great Civil War against his rival for power, Pompey. The last appearance of "Caesar's Comet," was in 44 B. C., on the death of Caesar. Its coming was foreseen in a dream by Caesar's wife Calpurnia, who warned him of the omen, as immortalized in Shakespeare's lines, put Into the mouth of Caesar's wife : "When beggars die, there are no Comets seen, The Heavens themselves blaze forth the death of Whose end is purposed by the mighty gods? Yet Caesar shall go forth; for these predictions Are to the world in general as to Caesar." Immediately after Caesar's death, records the Roman historian Suetonius in his "Life of Caesar" : "A Comet blazed for seven nights together, rising always about eleven o'clock, visible to all in Rome. It was taken by all to be the soul of Caesar, now received into Heaven; for which reason, accordingly, Caesar is represented in his statue with a star on his brow." Only one more Comet is recorded in ancient history before the birth of Christ. This was the Comet, now identified as Halley's Comet, which shone over the dense forests of Germany, eleven years before the birth of Christ, when Drusus, the brother of Tiberius, was warring against the ancient Germans and robbing them of their last vestige of liberty. At the same time fell the death of Agrippa, who ruled over the Roman Empire in the absence of Augustus. ing star. Many sacred writers have held, and many still hold, as did the distinguished American astronomer R. A. Proctor, that the "Star of Bethlehem," whose shining trail guided the Wise Men from The East, was a Comet. Lubienitius in his "History of Comets" expressly mentions the Star of Bethlehem as the most important Comet of history. As a matter of fact our modern astronomical computations prove that a Comet appeared in that year so as to be visible to the naked eye over Arabia, Syria, and the Holy Land. When this Comet appeared Herod was King of Judea. On the appearance of the Comet, Herod consulted the oracle of the Sibyl in Rome. She told him that the Comet shone in token of a boy destined to be far greater than he. Herod grew so afraid at this that he caused to be murdered his own two infant sons, Aristobolus and Alexander, and after that his eldest son, the boy Antipater. Herod further ordered the massacre of all male infants born in Judea under this Comet, as told in the Gospel of Matthew (Chap. II., Verse i). As the Comet kept on blazing in the sky, Herod, becoming desperate, tried to kill himself. Five days after this he died of a loathsome disease. "The people, half asleep, sat up and looked; then they became wide awake, though wonder struck. . . . Soon the entire tenantry of the house and court and enclosure were out gazing at the sky. "And this is what they saw : A ray of light, beginning at a height immeasurably beyond the nearest stars, and dropping obliquely to the earth; at its top, a diminishing point; at its base, many furlongs in width; its sides blending softly with the darkness of night; its core a roseate electrical splendour. The apparition seemed to rest on the nearest mountain southeast of the town, making a pale corona along the line of the summit. The khan was touched luminously so that those upon the roof saw each others' faces all filled with wonder. but once again while the mystery continued. "'Brethren!' exclaimed a Jew of venerable mien, 'what we see is the ladder our father Jacob saw in his dream. Blessed be the Lord God of Our Fathers!' ' been revealed to them. "Suddenly, in the air before them, not farther up than a low hill-top," writes Lew Wallace, "flared a lambent flame; as they looked at it, the apparition contracted into a focus of dazzling lustre. Their hearts beat fast; their souls thrilled; and they shouted as with one voice: 'The Star! the Star! God is with us!' " COMETS SINCE CHRIST OINCE the time of Christ, thanks to the spread of ^ Christianity and learning, with the growing zeal for keeping records and studying the stars, a far greater number of Comets and events connected therewith have been recorded. A number of learned writers have made a special study of the history of Comets and their effect upon man. Long before Lubienitius' ponderous work on the subject there were other histories written in Latin and Arabic, with references to which his book abounds. Since then others have followed in the same direction, notably Pingre, Hind, Lalande, Messier, Chambers and latterly Messrs. Crommelin and Cowell, of the Greenwich Observatory. The number of known Comets has grown immeasurably since Galileo's invention of the telescope, 300 years ago, and our later perfections of this instrument, together with latter-day devices for photographing Comets invisible to the naked eye. It would carry us too far to trace the possible connection between modern events and Comets that were seen only by astronomers. Since our record of Comets is already too full, we shall limit our story of the Comets and their influence upon man to a bare recital of the most important events connected with the more memorable and conspicuous Comets from the time of Christ until now. ished. 79 — Death of Emperor Vespasian, who began the siege of Jerusalem. The Roman historians Dion Cassius and Suetonius relate that Vespasian, when taken sick, heard his astrologers discussing in a low tone of voice the Comet which was then visible, which they said predicted his death. The Emperor roused angrily and said: "This hairy star is not meant for me. It must be meant for my enemy, the King of the Parthians, for he is hairy, while I am bald." pain, and the Comet was seen no more. Shortly after Vespasian's death followed the fierce eruption of Mt. Vesuvius, Nov. i, which destroyed the two flourishing cities of Herculaneum and Pompeii. 217 — From a Comet which shone for eighteen nights soothsayers predicted the death of the Roman Emperor, Caracalla. The Emperor was murdered immediately afterwards by his rival Macrinus. 312 — A Comet in the sign of a cross seen by Constantine the Great during battle of Saxa Rubra under the walls of Rome. Constantine was victorious and afterward turned to Christian faith. Asia and Europe. 399 — This Comet was described by Nicephorus as "of prodigious magnitude and horrible aspect, with a point like a sword and fiery hair reaching nearly to the ground, from which a great peril to the people was predicted." Its appearance was followed by the conquest and capture of Rome by Gainas. 410 — A sword-shaped Comet shone over Italy for four months until the third week in August. On Aug. 24 Rome was taken and plundered by Alaric, King of the Visigoths. This marks the end of the old Roman Empire. 449-50 — Two Comets (now believed to be coming and going of Halley's Comet) were observed over England and France. First invasion of England (44) by the Anglo-Saxons under Hengist and Horsa. Attila overthrown in the great battle on the Catalaunian Fields, at which a hundred and eighty thousand warriors fell, among them Theoderic, the King of the Goths. The Roman historian Callimachus recorded that this battle was preceded by a brilliant Comet and an earthquake. 531 — Comet observed in Constantinople by the astronomers of Emperor Justinian. Earthquake in Constantinople followed by famine and uprising of the people in which two thousand were killed. Pestilence. Mohamet begins preaching the Koran. 622 — Flight of Mohamet to Medina. 624 — Fourth scimitar-shaped Comet over Arabia and as Emperor of Rome. 814 — Torch-shaped Comet seen in Germany during the first three weeks of January. Death of Charlemagne on Jan. 28, at Aix la Chappelle. The monk Eginard relates in his chronicles that on the appearance of the Comet all those at Charlemagne's court feared for, the Emperor's life. Eginard preached to them from the text of Isaiah not to believe in the signs of the heathens. But Charlemagne reproved him, saying that he felt that he had reason to thank God for having sent him a timely warning of his impending death. Thereupon the Emperor made his testament and divided his empire among his successors. On the day following the disappearance of the Comet, he died. by disastrous earthquake. tooo — In January of this year a Comet was observed all over Europe. Gigibertus describes it "shaped like a horrible serpent and so bright that its light was seen even indoors." It was generally taken to foretell the end of the world, — the millennium prophesied in the Apocalypse. When it was followed soon by earthquakes, floods and famine there was universal panic which was not allayed until the end of the "fateful year." sacre of all Danes in England by King Ethelred. 1066 — Halley's Comet. It appeared in May at Easter time and shone for forty nights, waxing and waning with the moon. William the Conqueror haled it as an omen of destruction to Harold of England just before the battle of Hastings. 1077 — Comet over Italy and Germany. Emperor Henry IV. of Germany was excommunicated by the Pope, followed by war in Italy and Germany. 1099 — Arabic astronomers record a Comet in the shape of a scimitar over Arabia and the Holy Land for six weeks in Spring and early Summer. First crusade and storming of Jerusalem by the crusaders on July 15 after a siege of five weeks. Bloody massacre of Mohammedans. Arab warriors in Morocco. 12 1 2 — Lance-shaped Comet shining over western Europe for eighteen nights. The Children's Crusade. Thousands of German and French boy crusaders perished or were sold into slavery. Bloody invasion of Tartar hordes into Russia and Poland. 1223^ — Preaching of fifth crusade. Outbreak of "Guelph and Ghibelline" war between Emperor Frederick II. of Germany and Pope Gregory the IX. 1264 — Very bright Comet observed shining all over Europe for three months. Pope Urban IV. died on the night of the Comet's disappearance. A Latin verse gained great currency in which it was said that the Comet portended "disasters, sickness, hunger, and war." The chronicles of that age ascribe to this Comet besides the death of the Pope a famine and pestilence in Italy, the ravages of the Russians into Poland and of the Slavs into Prussia. Comets of Bloodshed. 1282 — An immense Comet over Italy. Disastrous earthquake in southern Italy. On March 30, a fortnight after the first appearance of the Comet followed the massacre of all Frenchmen in Sicily on the evening of Easter Monday, known in history as the "Sicilian Vespers." 1298 — Because of the appearance of a Comet over middle Germany, there were riots in Nurenberg and other neighbouring cities followed by a general massacre of the Jews in those cities. 1300 — A brilliant Comet preceded the Jubilee of Pope Boniface the VIII. The Pope interpreted the Comet as a happy omen, but because of the popular dread of the Comet there were riots and blood shed in Rome and elsewhere in Italy. The chroniclers of the times pointed out the significant fact that shortly after his jubilee Pope Boniface was made a prisoner by King Philip of France, causing him to die of rage. 1382 — Arab astronomers and Chinese report a very bright Comet which shone a fortnight. Tamerlane and his hordes overrun Central Asia. Tamerlane carries war into Europe and takes Constantinople by storm. Sultan Bayezid is taken prisoner by Tamerlane and is carried to Asia in a cage. 1492 — Arab astronomers record a Comet over northern Africa and Spain. Final conquest of Granada from the Moors by Ferdinand and Isabella of Spain. Discovery of the New World. lowed by Tartar invasion into Russia and Poland. 1528 — A Comet noted by Ambroise Pare, who recorded that many people fell sick and died of fright. War between Emperor Charles V. of Germany and Francis I. of France, with fighting in France, Germany and Italy. 1531 — Halley's Comet. Plague in Italy. Great schism in the Church. Defection of German Protestants from Rome. Henry VIII. of England declares English Church independent of Rome. Sultan Soleyman ravaged Hungary. Disastrous floods in Holland, where 400,000 people were drowned. 1556 — Emperor Charles V. of Germany and Spain, on account of his fear of the Comet that appeared in that year, abdicated his throne and became a monk. Wide-spread wars all over Europe. The Turks ravaged Hungary. Persecutions of English Protestants under uBloody Mary." Many Protestants burned at the stake, beheaded or broken on the rack. lowed by Civil War in France. 1607 — A Comet seen over Constantinople for several weeks. Wide-spread war on the part of the Turks against the Persians on one side, the Poles on another, and against Venice on the third. (50) 1618 — A blood-coloured Comet observed just before the execution of Sir Walter Raleigh in England. A bloody rising of the Protestants in Bohemia, followed by the outbreak of the terrible Thirty Years' War in Germany and the Netherlands. This was the Comet which gave rise to the German school rhyme: "Eight things a Comet always brings, Wind, Famine, Plague and Death to Kings, War, Earthquake, Floods and Dire Things." 1 66 1 — Inspired by. the appearance of a Comet, a horde of fanatics under Venner, a cooper, preached the coming of the "Fifth Monarchy" in England, and proclaimed Jesus Christ as their only King. The fanatics were routed and put to death. Death of Mazarin, the "Master of France." ^ Rise of Louis XIV., the most powerful ruler of /\ France. French war against the Pope. 1680 — This Comet was studied by Halley, in Paris, and by Newton, in England. It was called "Heaven's Chariot." Plague in Europe. The French overrun Alsace and carried war into Germany. War between Venice and the Turks. gary against the Turks. 1689 — A remarkable Comet observed all over Europe, followed by war all over Europe. Wars between France, Germany, England, Spain and Italy. The Rhine lands were harried by the French with fire and sword, rendering 4,000,000, people homeless. Burning of the castle of Heidelberg by the French. Religious war in Ireland and Scotland. 1744 — A six-tailed Comet observed in Germany just before the death of Emperor Charles VII. His death followed by war between Frederick the Great and Maria Teresa of Austria. War spreads to England, Holland, France, Spain and Italy. A British fleet beaten by French and Spaniards off Toulon. which 40,000 people lost their lives. 1759 — Halley's Comet. Seven Years' War in Germany. French lose Canada by their disastrous defeat of the plains of Abraham, and lose India by the loss of their fleet through three successive defeats on the sea. 1769 — "Napoleon's Comet." A Comet of unusual red lustre was observed over Italy and France. French overrun Corsica. Bloody massacre of Corsicans. Birth of Napoleon on August 15 in Corsica, just after the Comet was seen no more. 1811-12 — This huge Comet was one of the most famous Comets of modern times. It was first seen in France on March 26, 1811, and was last observed over southern Russia on August 17, 181.2 — an appearance of seventeen months, the longest on record. For a while it had two tails, then only one. The length of this tail was estimated as 100,000,000 miles. It was called "Napoleon's Comet." Under its lustre Napoleon gathered his "grand armee," the greatest army assembled in Europe since Xerxes, and invaded Russia. Wars were fought at the same time in Portugal and Spain, where the British stormed Ciudad Rodrigo and Badajos; and in America, where Harrison's victory over the Indians under Tecumseh at Tippecanoe, and the seahght between the "President" and "Little Belt" ushered in the War of 1812. In Egypt the Comet was taken as an omen of the bloody massacre of the Mamelukes prepetrated at Cairo. 1821 — "Napoleon's Comet." Seen one night only over France and over St. Helena the night before the death of Napoleon at St. Helena. 1823 — A Comet much mentioned by Spanish writers. While it shone over Spain, South America and the Mediterranean, the French overran Spain and reinstated the Spanish king. War of Independence in Central and South America. Bloody war of Greek Independence. 1835-6 — Halley's Comet. New York City all but destroyed by fire. Zulu massacre of Boers at Weenen. Mexican massacre of Americans at the Alamo. Wars throughout South America. 1843— Another famous Comet seen all over the world during the Spring of that year. Especially brilliant in the Southern Hemisphere and in India. War in India on the part of the British against Afghanistan, Beluchistan, Scinde and against the Sikhs. 1848— Encke's famous periodic Comet. Bloody revolutionary risings and civil wars in France, Hungary, Bohemia, Austria, Germany, Italy and Poland. (54) 1858-9 — Donati's Comet. This Comet, which appeared to be charging straight down from the zenith, and had a curved tail, was observed from June 1858 to April 1859. ^ was seen at lts brightest in the South, in Italy, Mexico and in the Far East. While it shone over the Far East there were bloody wars between the British and the risen people of India; between the British and the Chinese, who objected to having opium thrust upon them; while Japan was in the throes of revolution and civil war. In Mexico the standard of revolt against the clericals was raised by Juarez, thus plunging Mexico into civil war and war with France. Immediately after the disappearance of the Comet war broke out in Italy between the French and Italians on one side and the Austrians on the other, ending in the bloody Battle of Solferino. Civil War Comets. 1 861— "First 'Civil War Comet." The brightest Comet of the nineteenth century. Sir John Herschel, the great English astronomer, said of this Comet: "It far exceeded in brightness any Comet I have before observed, those of 1811 and the recent splendid one of 1858 not excepted." The Comet was first seen by a layman, and appeared at its brightest during the Summer months in North America. Its coming was heralded as a token of the great Civil War which broke out then in America. 1862— "Second Civil War Comet." Another Comet of very peculiar appearance, with jets of flame flaring from its head, showed itself during the Summer months in North America. The Civil. War was then at its height. The coming of the Comet was taken to herald the bloody battles of Shiloh, Williamsburg, Seven Days, Seven Pines, Cedar Mountain and Antietam, all fought that year after the Comet's appearance. 1874 — Coggia's Comet. This Comet was seen at its brightest over Southern France and Spain during the Summer months of that year. Spain was then in the throes of the bloody Carlist War. 1 88 1 — Garfield's Comet. This Comet showed itself for a few nights only in March during the week following President Garfield's inauguration. It was observed also in Russia. On March 13, Emperor Alexander II. of Russia, was assassinated with a bomb. Three months later President Garfield was assassinated in Washington. 1882 — Comet of Tel-el-Kebir. A Comet with two tails was seen at its brightest over Egypt during the first two weeks of September. Egypt was then in the midst of Arabi Pasha's uprising against the British. On September 18, when the Comet was last seen, Arabi Pasha was overthrown by General Wolseley in the bloody battle of Tel-el-Kebir. 1904-5 — Manchurian War Comet. From the early part of February, 1904, until Midsummer, 1905, Chinese observers recorded the appearance of a Comet over Northern China. Ross on March 17, remaining visible for one month. Observed from the Lick Observatory in California. On April 17 came the California earthquake and burning of San Francisco. 1908 — Morehouse's Comet. Visible for more than a month, during the autumn. In Italy it was interpreted afterward as an omen foreboding the Messina earthquake late in the year. This Year's Comets. 1910 — Inness' Comet, otherwise known as "1910 A." An unexpected Comet of short duration during January. On the appearance of this Comet Madame de Thebes, a French astrologer, predicted floods and general disaster for France. The disappearance of the Comet in France was followed by unprecedented rains arid floods which covered one-fourth of France with water and inundated Paris, completely submerging all the bridges over the Seine. Floods also in Italy and Germany. This Comet was likewise observed in China late in January, where it caused universal consternation. 1910 — Pidoux's Comet. Another unexpected Comet was first observed by Pidoux, in Geneva, during a few nights late in February. It is recorded astronomically as "1910 B.". Its fleeting observations by astronomers were followed by Socialist franchise riots in Germany and by the labour riots of Philadelphia, with widespread bloodshed between the rioters and the constabulary. 1910 — Halley's Comet of this year was first "picked up" by Dr. Wolf, in Germany. Already various astrologers have foretold disaster from its coming. It remains to be seen whether their predictions will come true. A MONG all the stars known in astronomy, the •f- periodically returning Comet now known as Halley's Comet has the most baleful record. asters. Not only war and battles, or other deeds of bloodshed, such as massacres and murders, but each of the dread disasters that are held to go with Comets have followed along one after the other in this Comet's train. Of the eight baneful after-effects of Comets mentioned in the old German ditty that has been sung in the Fatherland ever since the great Comet which ushered in the dreadful Thirty Years' War, every form of these evils in turn. Directly after each return of Halley's Comet there has always followed somewhere within the influence of its rays one or other of those "dire things," — a flood, an earthquake, a hurricane, famine, plague, war, bloodshed, or the sudden death of a ruler. Thanks to the careful work of such painstaking astronomers and historians as Lubienitius, Pingre, Dionys de Sejour, J. Russell Hind, Laugier, and Messrs. Cowell and Crommelin, the records of great events connected with Halley's Comet have been traced back nearly 2,000 years, to the days before Christ. Among the signal events following in the train of this Comet there have been so many bloody massacres and appalling disasters that Halley's Comet now has the ominous distinction of being the bloodiest of all stars of ill omen. Herewith follows the story of this Comet's periodic appearances in history and of the events connected therewith, as traced back from its last return in 1835 to its first recorded entrance into the history of mankind. It was first discerned by Father Dumouchel with a powerful telescope from the observatory of the Collegio Romano in Rome on the night of August 6, 1835. Father Dumouchel, who had been watching for it many months, picked it up close to the spot in the heavens that Rosenberger, a German astronomer, had predicted for its appearance .on that date. until the middle of May, 1836. Other noted astronomers who made observations of it were Arago, Struve, Bessel, Kaiser, Sir Thomas Maclear, Admiral Smyth, Baron Damoiseau and Count Pontecoulant. This last astronomer, many years before, had computed the exact time of its coming and came within four days of it. For this brilliant feat Count Pontecoulant received a gold medal from the French Academy of Sciences. The German astronomer, Rosenberger, who had likewise computed the Comet's return, coming within five days of its passage nearest to the Sun, received a similar gold medal from the Royal Astronomical Society of Great Britain. Professor Struve, who studied the Comet through the great telescope at Dorpat in Russia, described it as "glowing like a red-hot coal of oblong form." Bessel, who observed it from the Koenigsberg observatory in Northern Germany, described the Comet's appearance as that of "a blazing rocket, the flame from which was driven aside as by a strong gale, or as the stream of fire from the discharge of a cannon when the sparks and smoke are carried backwards by the wind." week of September. Immediately after the Comet became generally visible in the Old World the bubonic plague, known of old as the "Black Death," broke out in Egypt. In the City of Alexandria alone 9,000 people died on one day. By the Moslems this calamity was generally attributed to the evil influence of the Comet. In America the Comet became visible to the naked eye only late in the year. Then, on its approach to the Sun, it was lost to view and passed over to the Southern Hemisphere where it was next observed by Sir John Herschel in South Africa. Shortly after its brief blaze over North America the great "New York Fire" laid waste the entire business section of the biggest city in the New World. All the commercial centre of the city, including the richest firms and largest commercial warehouses, were laid in ashes. The fire raged through days and nights. In all, 530 the homeless were pitiable. Down in Florida, at the same time, Osceola, the chieftain of the Seminole Indians, called upon the Comet as a signal for war against the whites. The Indians called the Comet "Big Knife in the Sky." The war began with a bloody massacre of American soldiers under General Wiley Thompson at Fort King. All were slaughtered. Osceola scalped General Thompson with his own hands. On the same day, Major Bade of the American Army, who was leading a relief expedition into Florida from Tampa Bay, was ambushed by the Indians near Wahoo Swamp and was massacred with his men. Of the whole expedition only four men escaped death. With the passing of the Comet to the Southern Hemisphere, bloody wars broke out one after another in Mexico, Cuba, Central America, Ecuador, Bolivia, Peru and Argentinia. All those countries were in a welter of blood. At the same time the American settlers of Texas declared themselves independent and made open war on Mexico. The war began with the bloody battle of Gonzales, in which 500 American frontiersmen fought and defeated over a thousand Mexican soldiers. This was followed by other fierce fights at Goliad and Bexar. Next came the bloody massacre of the Alamo, when all of Jim Bowie's and Davy Crockett's American followers were killed in an all night fight. Out of 200 Americans every man fell at his post. This was the deed lad of the Alamo. "Santa Ana came storming as a storm might come, — There was rumble of cannon; there was rattle of blade; There was cavalry, infantry, bugle and drum, — Full seven thousand, in pomp and parade, The chivalry, flower of Mexico, And a gaunt two hundred in the Alamo." One month before the final disappearance of the Comet, the Texas War came to an end with the bloody battle of San Jacinto, when Sam Houston, with 800 American frontiersmen, defeated 1,500 Mexicans, and made a prisoner of President Santa Ana of Mexico. sphere, it was seen at its brightest in South Africa. The pious Boers of Cape Colony understood it to be a sign from heaven and forthwith set out on their great trek across the Orange and Vaal rivers, where they founded the Orange Free State and Transvaal Republic. woful significance for the blazing of the Comet. Under the leadership of Piet Relief, a thousand Boer families had trekked across the Drakensberg Mountains into Natal. A solemn treaty of peace with the Zulu warriors was entered into with Dingaan, the chief of the Zulus at Dingaan's Kraal. Suddenly the Zulus pounced upon the unsuspecting Piet Relief and his sixty-five Boer followers and massacred them to a man. trains. Near Colenso, at a spot called Weenen (weeping), in remembrance of the dreadful tragedy there perpetrated, the Zulus overwhelmed the Boer laager and slaughtered all its inmates — 41 men, 56 women, 185 children and 250 Kaffir slaves. After this bloody massacre, equalling in horror the Massacre of the Alamo on the other side of the world, the Comet of 1835-36 was seen no more. THIS was the first return of the Comet predicted by Halley. Hence it must be reckoned as the first appearance of "Halley's Comet" under his name. It was first seen on Christmas night, 1758, by John Palitsch, a Saxon farmer, near Dresden, who was looking for it with a self-constructed telescope of eightfoot focus. The Comet did not become visible to the naked eye until well into 17.59. It pa^sed_around the sun on March 12, 1759. After that it was seen throughout Europe during April and May, appearing at its brightest during the first week in May. Later it was seen to advantage in the Southern Hemisphere. In Germany, where it was seen at its fiercest, the Comet was taken as a token of the bloody Seven Years' War, which was then being fought between Frederick the Great and his enemies on all sides. The ominous Comet had scarcely vanished from view when all Germany was overrun by marching armies from France, from Austria, from Russia. The French, under the Duke of Broglie, overthrew the Germans, under the Duke of Brunswick, at Bergen, and seized the city of Frankfurt. Then came the bloody battle of Minden, in which two large French armies Within a fortnight King Frederick the Great and his whole army were overthrown by the Austrians and Russians in the disastrous battle of Kunersdorf. fighting. For the French, the Comet signalled disaster after disaster. After their armies had been beaten in Germany, their navy was defeated on August 17 in a great sea fight in the Bay of Lagos, on the coast of Portugal. Six weeks later there was another bloody sea fight between the British and French, when Admiral Pocock inflicted a telling defeat on the French fleet. Then came the final French naval disaster off Quiberon, in the Bay of Biscay, when Admiral Hawke destroyed French naval power by sinking or blowing up over a score of the French fighting ships. This bloody defeat was a disaster of untold consequences to the French, since it meant the loss of India. brought to the French. On September i3th of that year the French lost their strongest hold on America in the disastrous defeat inflicted upon them by General Wolfe in the bloody battle on the Plains of Abraham, where Wolfe himself fell fighting. On the French side, General Montcalm, the Commander-in-Chief, was mortally wounded. This meant the loss of Quebec and of all Canada to the French, an event of far-reaching importance that has changed the destiny of all America and of the modern world. THE Comet which put Halley on the right track in his theories of Comets, first came into view on the night of August 15, 1682. It was first detected by Flamsteed's assistant at the Greenwich Observatory, while searching the northern heavens with a telescope. Flamsteed, the first Astronomer Royal, and Halley, his successor, kept a close watch upon the Comet every night, and followed its course over the sky. Others who watched it were Sir Isaac Newton, Cassini, Picard and La Hire in Paris, Baert at Toulon, Kirch and Zimmermann in Germany, Montanari at Padua, and Hevelius in Dantsic. They observed that the tail lengthened considerably as the Comet came nearer the sun. Later a jet of luminous matter was seen shooting out toward the sun, which afterward fell back into the tail. Hevelius has left us a drawing of this phenomenon. On November nth, Halley found that the Comet had come within a semi-diameter of the path of our earth. This startling discovery caused Halley to reflect what might happen if the earth and the Comet had arrived at the same time at the spot in space where their two orbits intersect. Assuming as he did that the mass of the Comet was considerably larger than our earth, he declared: "If so large a body with so rapid a motion were Dr. Whiston — he who succeeded Newton in the Lucasian chair of mathematics at Cambridge — in a moment of prophetic vision fervently declared that this Comet was God's agent that would bring about the General Conflagration by involving the world in flames. In America, the Rev. Increase Mather, President of Harvard College, on the appearance of the Comet in New England, preached his great sermon on "Heaven's Alarm to the World . . . wherein is shown that fearful sights and signs in the Heavens are the presages of great calamities at hand." Increase Mather's warning was handed down as an inspired prophesy, in view of the fact that the English settlers in North America soon afterwards got into bloody warfare with the Indians. The war raged at its fiercest in the Carolinas, where the English settlers made war upon the redskins simply for the purpose of taking them captive and selling them into slavery in the West Indies. To the Indians the Comet appeared as a sign of ill omen, as shown by their frequent references to it during the parleys with the white men. The Comet was shining at its fiercest when the six greatest chiefs of the Susquehanna nation were enticed into a pretended council of peace with the white men, only to be foully murdered with all their followers. While this was going on in America, the Comet gave the signal in India for the first hostilities there upon the white settlers from Portugal, as well as for the outbreak a generation to come. Nearer East, the Turks, under the leadership of Mohammed Bey, ravaged Egypt, while, on the other side, a Turkish army under Kara Mustapha carried war into Hungary, to the very gates of Vienna, until Emperor Leopold felt constrained to call for help from Sobieski, the warrior king of the Poles. seized the German city of Strasburg. At the same time the bubonic plague broke out in North Germany. In the little university town of Halle alone, within a few days, 4,397 people died out of a total population of ten thousand. /T^HE Comet this year was seen all over Europe. The best observations of it were made by Kepler and Longomontanus (Langberger). It was seen at its brightest in England. Shortly after its appearance over England, there came freshets and floods which completely submerged the richest counties of England. In Somersetshire and Gloucestershire the water rose above the tops of the houses. This was followed by a visitation of the plague. his English garrison. In Germany the Comet was taken as a token of the war then brewing between the Emperor and the German Protestant Princes — the so-called Protestant League — which ushered in the dreadful Thirty Years' War in Germany. Off Gibraltar, a Dutch fleet completely destroyed a fleet of Spanish war galleons, thereby crippling Spanish sea power for a generation to come. Meanwhile, in America, the early settlers in Virginia, led by John Smith, found themselves beset by the redskins, who were incited to war by the appearance of the Comet. They called it "Red Knife in the Sky." During the war, John Smith was taken prisoner, and escaped with his life only through the intercession of Pocahontas, the daughter of Powhattan. E Comet was first sighted by the German astronomer Bienewitz ("Apianus") in midsummer of this year. Zwingli preached about it as an omen of disaster. German astrologers regarded it as a herald of the wars between Spain and France, which broke out in that year, and of the bloody war carried into Hungary by the Turks under Soleyman, who ravaged the Danube country to the very walls of Vienna. These wars were followed by a visitation of the black plague. To the aborigines of South America it proved a star of dreadful omen. During this year the most cruel of Spanish conquerors did their bloodiest work in the New World — Cortez in Mexico, Alvarado at the Equator, and Pizarro in Peru. Before the Comet disappeared from view, several hundred thousand wretched Incas and Aztecs had been slaughtered by the Spaniards, while many more hundred thousands were worked to death as slaves. T^HE Comet this year was observed throughout Europe and also in China. It came into view over Europe on the 29th of May, and was seen gliding over the sky towards the moon. Writers of that period say that it shone with ^exceeding brightness and spread out a fan-shaped train of fire. The Arab astronomers describe its shape as that of a Turkish scimitar, which, blazing against the dark sky, was regarded as a sign from heaven of the war then raging against the Christian infidels. A clear story of the Comet's appearance has been left by the Bavarian Jesuit, Brueckner (Pontanus). He based his story on the record of Georgos Phranza, Grandmaster of the Wardrobes to the Emperor of Constantinople. There the Comet is described as "rising in the West; moving towards the East, and approaching the Moon." By the Chinese this Comet was described as having a tail sixty degrees long, and a head "which at one time was round, and the size of a bull's eye, the tail being like a peacock's." Halley wrote of this Comet in 1686: "In the summer of the year 1456 a Comet was seen, which passed in a retrograde direction between the earth and the sun. From its period and path, I infer that it was the same Comet as that of the years 1531, 1607 and 1682. 1 may therefore with confidence predict its return in the year 1758." The appearance of the Comet in 1456 was so well remembered even 225 years later, because this was the scimitar-shaped Comet hailed by the conquering Turks as their guiding star, against the evil influence of which Pope Calixtus III. exhorted all Christians to pray to God. This story has been denied by certain latter-day sceptics, but the medieval historian Platina, who was living in Rome at the time, and who knew whereof he spoke, wrote in his "Lives of the Popes" in 1470: "A hairy and fiery star having then made its appearance for several days, the mathematicians declared that there would follow grievous pestilence, dearth and some great calamity. Calixtus, to avert the wrath of God, ordered supplications that if evils wrere impending for the human race He would turn all upon the Turks, the enemies of the Christian name. He likewise ordered, to move God by continual entreaty, that notice should be given by the bells to call the faithful at midday to aid by their prayers those engaged in battle with the Turk." In truth, all Christendom appeared indeed to have fallen under the "wrath of God," for the Turks, having wrested Constantinople away from the Christians, now came ravaging up the Danube countries and laid siege to the Christian city of Belgrade. Bloody battles were fought between the Magyars and Turks on the Danube, until Hunyadi, the great Magyar leader, at last overthrew the Turks under Mahomet II. , under the walls of Belgrade, in a great battle, in which no less than 24,000 Turks were slain. This was on July 2ist, on the eve of which day the Comet had been seen to blaze at its fiercest. ^ I AHE Comet appeared late in the year, and was seen at its brightest over Northern Europe, in Scotland, Scandinavia, Russia and Poland. All these countries, during the same period and immediately afterwards, were cursed by the terrible pestilence called the "Black Death," now known to have been the worst visitation of the bubonic plague known in history. Wherever the dread sickness appeared, the people "died like rats." So many succumbed to the disease, and so many others fled aghast from the pestilence, that whole cities and towns were left empty, and no labourers could be found to till the fields. HP HE Comet this year was first observed by German and Flemish astrologers during the late Summer and Autumn. It was interpreted as an ill omen of the wars which then ravaged Europe. Immediately after the appearance of the Comet, Emperor Albrecht of Germany ravaged the Rhine lands with fire and sword. Afterwards the German astrologers explained the Comet as a warning omen of the death of the Emperor's son Rudolf, who died within a twelvemonth of his coronation as King of Bohemia. Flanders. Soon after this came Robert of Artois' bloody defeat at Coutrai, the famous "Battle of the Spurs," so called from the thousands of gilt spurs that were taken afterwards from the feet of the slain French cavaliers. October. The Comet was taken as a special omen of the terrible fate of the City of Herat and its surrounding country, where the bloodthirsty conqueror caused to be slaughtered over a million of people. Jenghis Khan, who believed in stars and omens, having been born with bloodstained hands, hailed the Comet as his special Star. Under its rays he extended his immense Empire to its outermost boundaries from the China seas to the banks of the Dniepr in Russia. After the Comet's disappearance, Jenghis Khan regarded the planets that had crossed its orbit as stars of ill omen, betokening his death, so he set his face backward from his march of conquest, and soon afterwards died in Mongolia. THE Comet appeared over Europe early in Spring. It was seen at Rome in March and April. Inspired by the appearance of the Comet, Pope Eugenius III. called for a crusade against the Moslems. St. Bernard in France took up the cry, and preached a holy war all over France. On Easter Sunday, King Louis VII. of France, his Queen and all his nobles, received the Cross from St. Bernard at Vizelay. In Rome, however, the Comet was taken as a token of the Pope's downfall. Arnold of Brescia preached against the Pope and aroused the Roman populace against him. The Holy Father had to flee. On the disappearance of the Comet, the Pope returned and excommunicated the Patricians of Rome. Arnold of Brescia was taken and strangled in his cell. Later historians, like Lubienitius, accordingly interpreted the Comet as a sign of warning rather than as an ill omen. >T^HIS is the most famous appearance of the Comet JL now known as Halley's Comet. Under its seven rays, that year, William the Conqueror felt inspired to fall upon England, while Harold, the Saxon, on the other hand, saw in the Comet a star of dread foreboding and of doom. The medieval chronicles of this year all make special mention of the Comet. A picture of the Comet, as it appeared to the doomed Harold, was embroidered by Matilde of France, on the famous coloured tapestry of the Norman Conquest, which is still preserved at Bayeux in Normandy. Zonares, the Greek historian, in his account of the death of Emperor Constantinus Ducas (who died in May, 1067), writes of the Comet as "large as the full moon, and at first without a tail, on the appearance of which the star dwindled in size." The Christian chroniclers record that this Comet, "in size and brightness equalled the full moon, while its tail, slowly lengthening as it came near the Sun, spread out into seven rays and arched over the heavens in the shape of a dragon's tail." Sigebert of Brabant, the Belgian chronicler of that time, wrote of it: "Over the island of Britain was seen a star of a wonderful bigness, to the train of which hung a fiery sword not unlike a dragon's tail; and out of the dragon's mouth issued two vast rays, whereof one reached as far as France, and the other, divided into seven lesser rays, stretched away towards Ireland." William of Malmesbury wrote how the apparition affected the mind of a fellow monk of his monastery in England. His words were: "Soon after the death of Henry, King of France, by poison, a wonderful star appeared trailing its long tail over the sky. Wherefore, a certain monk of our monastery, by name Elmir, bowed down with terror at the sight of the strange star, wisely exclaimed, Thou art come back at last, thou that will cause so many mothers to weep; many years have I seen thee shine, but thou seemest to me more terrible now that thou foretellest the ruin of my country.' ' Another old Norman chronicler, by way of defending the divine right of William of Normandy to invade England, wrote: "How a Starre with seven long Tayles appeared in the Skye. How the Learned sayd that newe Starres only shewed themselves when a Kingdom wanted a King, and how the sayd Starre was yclept a Comette." months while William was preparing his expedition at St. Valery. When the spirits of his followers failed them, William pointed to the blazing Comet and bid monks and priests who accompanied his expedition to preach stirring sermons on the "wonderful Sign from Heaven." The trip across the English Channel, late in September, was lighted up by the Comet, and under its lustre the Norman invaders first pitched their camp at Pevensey. Once more, when William's Norman followers quailed at the fierce work before them, William pointed to the Comet as a token of coming victory. A fortnight later, directly after the disappearance of the Comet, the Battle of Hastings was fought, in which King Harold and his Saxon thanes lost their lives and their country. Afterwards, when Queen Matilda nnd her court ladies embroidered the pictorial story of her husband's Conquest of England in the huge tapestry of Bayeux, they did not forget the Comet. They represented Harold cowering in alarm on his throne, whilst his people are huddled together, pointing with their fingers at the fearful omen in the sky, the birds even being upset at the sight. The Latin legend over the picture "Isti Mirant Stella" (they marvel at the star), makes it all plain. As I. C. Bruce, the editor of "The Bayeux Tapestry Elucidated," has said: "This embroidery is remarkable for furnishing us with the earliest human representation we have of a Comet." The Comet of 1066 will ever be famous for ushering in a new era for England. Even to-day Halley's Comet is remembered as "The Comet of the Conquest." while the heathen Danes and Wends ravaged Germany. pHE Comet appeared early in the year and was seen over Germany, as noted in the chronicles of the monks of St. Callus in Switzerland. Immediately after the appearance of the Comet, Germany was ravaged by war, both inside and outside, the Empire being invaded on all sides by the Danes in the North, the Slavs in the Northeast, and the Magyars from Hungary. r I AHE Chinese Astronomers record two Comets for this year, one in February, and the other in April. But the modern view is that this was the same Comet, as seen going to the Sun, and afterward, when it was coming away from the Sun. Immediately after the appearance of the Comet there followed a widespread rebellion in China with much bloodshed and fierce reprisals. The only Christian record of the Comet we have is that of Eginard, an astrologer employed at the Court of Louis the Debonair, in France. This is Eginard's account of the Comet: "In the midst of the holy festival of Easter there shone forth in our sky a sign always ominous and of sad foreboding. As soon as the Emperor — who was in the habit of gazing up into the sky at night — first saw the Comet, he had me called be- of the sign in heaven. " 'Let me have but a little time,' I asked of him, 'that I may study this sign and see the exact constellation of the other stars around it, thus to gather from the stars the true meaning of this portent,' promising him that I would tell him on the morrow of the results of my studies. "But the Emperor, guessing that I was trying to gain time — as was indeed the truth, lest I be driven to tell him something unlucky and fatal to him — he said to me: " 'Go up on the terrace of the palace and look. Then come back at once and tell me what thou hast seen! For I did not see this star last night; nor didst thou point it out to me; but I know that sign in heaven is a Comet. Thou must tell me true what it forebodes to me!' "Then, before I could say anything, he said: 'There is another thing thou art hiding from me. It is that changes in Kingdoms and the deaths of rulers are foretold by this sign.' "To soothe him I reminded the Emperor of the words of the Prophet Isaiah, who said: 'Fear not signs in the Heaven, like unto the Heathen.' "But the Emperor smiled sadly and said: 'We should believe only in God on High, who has created us and also all Stars in Heaven. Since He has sent this Star, and since this unlocked for Sign may be meant for us, let us look upon it as a warning from Heaven.' ' Thereupon Louis the Debonair betook himself to fasting, prayers, and the building of churches and shrines, he and all his Court. Shortly thereafter he died. The French chronicler, Raoul Glaber, afterward wrote in his chronicle: "Comets never show themselves to man without foreboding surely some coming event, marvellous or- terrible." A Comet appeared in the Spring of this year, which •• • without any doubt whatever was Halley's. It was recorded in detail both by European and Chinese annalists, and its orbit has been calculated and identified by Laugier. A Greek record of Constantinople tells how "a Comet like a great beam and very brilliant was observed in the twentieth year of Emperor Constantine V., surnamed Copronymus, first in the East and then in the West, for about thirty days. Its appearance was followed next Winter by a biting frost throughout the Orient, which endured 150 days, from October until February, blighting all crops in Egypt and elsewhere in the Eastern Empire. HINESE annals record a Comet observed in the West in September and October. This accords with the computed time for the course of Halley's Comet that year. Immediately after the Comet's appearance, China and the Far East were ravaged by the black plague. Millions died of it. Baeda the Venerable, in his "Chronicle of the English People," records that the plague also reached England. A LL Europe and the former Roman Empire were in •" • such dire confusion during this period that no records of this year, either astronomic or historical, have come down to us. Messrs. Cowell and Crommelin, however, have computed astronomically that the Comet must have appeared during this year. All we know is that Italy and the Latin World were overrun by ravaging Slavonian hordes from Hungary, who made all the country run with blood. OF THE Comet this year, likewise, there is no astronomic record. All we know is that the appearance of a Comet is noted in European chronicles. It was followed by a virulent outbreak of the black plague. In the legendary history of Merlin, the ancient British seer, it is stated that on the appearance of a Comet this year he prophesied that Uter, brother of Ambrosius, on the death of the latter, should rule the kingdom; that a ray from the Comet which pointed toward Gaul presaged a son who should be born to him and who should be great in power; and that the ray "that goes toward Ireland represents a daughter, of whom thou shalt be the father, and her sons and grandsons shall reign over all the Britons." These prophecies all came true. on the Catalaunian Fields (Chalons-sur-Marne), when Aetius, the last of the Romans, together with King Theoderic and his Goths, stemmed the tide of Hunnish invasion led by Attila, the "Scourge of God." Theoderic, together with 148,000 warriors on both sides, were slain in this tremendous fight, which alone saved Europe from Tartar savagery. HINESE annals of this year record a Comet seen in the northern constellation of Ophiuchus in October. This year marks the beginning of the tremendous migration of peoples, which started in Mongolia and Tartary, and crossing the Volga gradually overflowed all the known world, like a huge human deluge. appearance of a Comet this year (identified by Hind with Halley's) was followed by a bloody rebellion of the ancient Britains against the Romans, and by another rebellion against Rome by the Egyptians. These patriotic uprisings of the people were suppressed with fire and sword and both countries ran with blood. r I ^HE Chinese catalogue of Ma-tuan-lin records a Comet with a path exactly analogous with the orbit of Halley's Comet computed for that year by Hind. In the Chinese record the Comet is described as "pointed and bright." Its coming was connected with the death of Emperor Ween-te directly afterward, and the Civil Wars between various claimants to the throne of the Celestial Empire, which then rent China asunder. Dion Cassius, the Roman historian, describes the Comet of this year as "a very fearful star with a^ tail stretching from the West towards the East." The Roman augurs explained the Comet as a portent of the bloody death of Emperor Macrinus of Rome, who was murdered by his own soldiers on the night after the disappearance of the Comet. TN THIS year the Chinese astronomers recorded a Comet in March and April (the time computed for Halley's Comet), which they described as "a star six or seven cubits long and of a bluish-white colour." The coming of the Comet was followed by a virulent outbreak of the plague in China and the Far East, which spread all over the known world. So virulent was this pestilence that in the City of Naples alone 400,000 people died of the disease. TJ ALLEY'S Comet, according to astronomic calculations, must have made its reappearance during the winter months of 65-66 A. D. The Chinese have recorded "two Comets," one in 65, which was seen for fifty-six days, and "the other" in February, 66, which remained visible fifty days. This was the Comet which St. Peter and Josephus saw over the City of Jerusalem, before the fall of the Holy City. Josephus wrote of it : "Amongst other warnings, a Comet, of the kind called Xiphias, because their tails appear to represent the blade of a sword, was seen above the doomed city for the space of nearly a whole year. Jerusalem was ravaged by pestilence and famine and soon afterward was stormed by the Roman soldiery led by Titus. The Temple was burned down and the streets of the Holy City ran with blood. It was the end of Jerusalem and of the Jews as a free city and people. B. C. 1 1 HP HIS is the farthest back that the appearances of Halley's Comet have been traced in history. For earlier appearances there are no sufficiently trustworthy computations or records. Dion Cassius in his "History of Rome" has recorded ua Comet which hung suspended over the City of Rome just before the death of Agrippa," who ruled over the Roman Empire during the absence of Augustus in Greece and Asia. Agrippa was so universally beloved, and his death was held to be such a loss to Rome that he was buried with imperial honours in the tomb intended for Augustus. The death of Agrippa occurred in the year 12, shortly after the disappearance of the Comet which Hind has identified with Halley's. T^HIS completes the record of all the known appearances of Halley's Comet. The record fully justifies Chambers' dictum, that the "Comet known as Halley's is by far the most interesting of all the Comets recorded in history." This historic record also appears to justify in no small measure the popular beliefs of the last two thousand years concerning Comets, as expressed by Leonard Digges in his book on Prognostics, published 350 years ago: "Cometes signifie corruption of the ayre. They are signs of earthquakes, of warres, of changying of Kyngdomes, great dearth of food, yea a common death of man and beast from pestilence." THE STORY OF EDMUND HALLEY T^HE great French astronomer Lalande considered Halley the greatest astronomer of his time. This opinion is still held. Halley's "time" means the age of Kepler, Sir Isaac Newton, Flamsteed, Hevelius, and Leibnitz, all of whom achieved first rank in Astronomy. Halley's greatest achievement in Astronomy was the discovery that our solar system was but an atom in immeasurable space whence wandering stars could be caught within the influence of our Sun, our Earth and the other Planets swinging around our Sun. Halley was the first to discover and to prove that the Comets that come within the vision of man have fixed periods of return. He made this discovery during the appearance of the great Comet of 1682, which has since been known by his name. In his studies of the motions of Comets, of which Halley computed the orbits of twenty-four, he observed that a Comet of similar phenomena, recorded by Appian in 1531 and by Kepler in 1607, had swung through the same orbit as the Comet under his observation in 1682. Halley surmised from this that these Comets might be one and the same, whose intervals of return appeared to cover a period of seventy-five or seventy-six years. Halley's surmise seemed to be confirmed by the recorded appearance of similar bright Comets in the years 1456, 1378, and 1301, the intervals again being seventy-five or seventy-six years. Halley was deeply imbued with Newton's new discovery of gravitation, for the publication of which Halley paid the expenses, so he brought the principles of Newton's theory of gravitation to bear on his own new theory of the motions of Comets. He rightly conjectured that Comets were drawn to our Sun across the disturbing orbits of our planetary system, and that the comparatively small differences of one or two years in the recorded intervals of this one Comet (Halley's Comet) were due to the attraction of the larger planets. During the previous year, 1681, Halley computed that the Comet had passed near the planet Jupiter, the attraction of which must have had a considerable influence on the Comet's motion. Making due allowance for this disturbing influence of Jupiter, he computed that the Comet would return to the vicinity of our Sun about the end of 1758 or beginning of 1759. Halley did not live to see his prediction fulfilled (he died in 1742), but he wrote shortly before he died: "If this Comet should return according to our predictions about the year 1758, impartial posterity will" not refuse to acknowledge that this was first discovered by an Englishman." All through the year 1758 the most noted astronomers of Europe were on the lookout for the return of the predicted Comet. One of these astronomers, Messier, looked for it through his telescope at the Paris Observatory every night from sunset to sunrise throughout that whole year. On Christmas night, 1758, the Comet was first seen by a German peasant near Dresden, who had heard about the Comet and was looking for it. He was a man of unusually good eyesight, yet his discovery was doubted until Messier, nearly a month afterward, at Paris, "picked up" the Comet with his telescope. EDMUND HALLEY. Besides this achievement, Halley accomplished many other noteworthy feats in astronomy, such as his discovery of the proper motions of the fixed stars; his detection of the "long inequality" of Jupiter and Saturn, and of the acceleration of the moon's mean motion; his theory of variation, including the hypothesis of various magnetic poles, with his suggestion of the magnetic origin of the aurora borealis; and his indication of a method still used for determining the solar parallax by means of the transits of Venus. On the strength of these achievements, Halley for many years was elected to serve as secretary to the Royal Society. Commissioned as a Captain in the Royal Navy, he also commanded a vessel on a long cruise of exploration, and late in life he was made Astronomer Royal. Although in his sixty-fourth year, he then undertook to observe the moon through an entire revolution of her nodes (eighteen years), and actually carried out his purpose. To appreciate the full significance of so painstaking an achievement it should be borne in mind that astronomical observations must be made in a temperature equal to that of the open air. Observatories cannot be heated because the heat would impair the accuracy of the instruments. Great astronomers, like poets, are born, not made. Edmund Halley was one of these. At the age of seventeen he had already observed the change in the variations of the compass. At nineteen he was recognized as an astronomer of reputation, having supplied a new and improved method of determining the elements of the planetary orbits. His detection of considerable errors in the tables then in use led him to the conclusion that a more accurate determination of the places of the fixed Stars was indispensable to the progress of astronomy. With this end in view he set out on a voyage to the other side of the globe, St. Helena, where he undertook the task of making complete new observations of the entire Southern Hemisphere. Though the Heavens proved clouded he succeeded within two years in registering three hundred and sixty stars, a colossal achievement which won for him the title of the "Southern Tycho." This was when Halley was barely of age. No one could well have begun with prospects more remote from so high a career, for Edmund Halley was born in 1656, the son of a soap boiler in a shabby London suburb. By his brilliant attainments in mathematics he won another scholarship to Oxford University. On his graduation from Oxford, the young would-be astronomer conceived the project of turning his attention to the southern Stars, of which no good observations had been made. Shortly before this time a Dutch astronomer, named Houtman, had observed these Stars in the island of Sumatra; and Blaeu, the best globe maker of the age, had used these new observations in the correction of his celestial globes. Halley, on examining these corrections, came to the conclusion that he himself could do better. He also concluded that the Island of St. Helena might be a better point for southern observations. His father, unable to pay the expenses of so long a trip, broached the project to some friends. The young astronomer was recommended to King Charles II. by Williamson and Jones Moore, and the King in turn recommended the youth to the Indian Company, which then had control over the island of St. Helena. After this all was plain sailing. The India Company placed a ship at his disposition and promised him all the assistance he required. Young Halley provided himself with telescopes, and micrometers, and other instruments of the latest approved pattern. In November, 1666, at the age of twenty, he sailed for St. Helena. Among his luggage was a sextant of five and a half feet and a telescope twenty-four feet in length constructed under the supervision of Flamsteed, the Astronomer Royal. Halley was disappointed in the climate of St. Helena. Frequent rains and a constantly hazy sky scarcely permitted any observations in the months of August and September. Notwithstanding these difficulties, he succeeded in observing and cataloguing some 360 Stars. In addition to his work on the Stars, Halley made some investigations on the Moon's parallax, combining his observations at St. Helena with those made in northern skies. He also evolved a new theory of the Moon's motion, which proved of great aid in the determination of longitudes. On November 7, 1677, Halley observed a transit of Mercury which suggested to him the important idea of employing similar phenomena for the calculation of the Sun's distance. Halley returned to England in November, 1678, and was hailed by his fellow astronomers as the "Southern Tycho." He was elected a fellow of the Royal Society, and by the King's command the degree of Master of Arts was conferred upon him by the University of Oxford. Six months later Halley set out for Dantsic for a personal conference with Hevelius, the Polish astronomer. Halley wanted to satisfy himself as to the accuracy of observations claimed by Hevelius without the aid of a telescope. Halley convinced himself that the errors of the observations made by Hevelius were less than had been supposed, and did not exceed a minute of an arc. The two became life-long friends. Halley proceeded to other cities of Europe where there were observatories. In Paris he observed with Cassini the great Comet of 1680. This was the beginning of Halley's special study of Comets. Returning to England, the young astronomer married the daughter of Mr. Tooke, auditor of the Exchequer, with whom he lived harmoniously until her death, fifty-five years later. The young couple settled at Islington, where Halley erected an observatory of his own and engaged in constant lunar observations with a view toward finding a method for computing longitudes at sea. Halley's mind at the same time was busy with the momentous problem of gravity, upon which Isaac Newton was working then. Independently of Newton, Halley reached the conclusion that the central force of the Solar System must decrease inversely as the square of the distance. Having applied vainly to his fellow astronomers, Hooke and Wren, Halley in August, 1684, made a special journey to Cambridge to consult Isaac Newton, who confirmed his conjectures. Halley and Newton became life-long friends. Halley had Newton elected to the Royal Society, and when Newton became too poor to pay his quarterly dues, Halley, through his influence with the leading members of the Society, had them remitted. It was Halley who encouraged Newton to put his momentous discovery and elucidation of the forces of gravity into permanent form in his "Principia," the first volume of which, "De Motu," was presented to the Royal Society at Halley's suggestion. In the proceedings of the Royal Society for December, 1684, there is an entry that "Mr. Halley had lately seen Mr. Newton at Cambridge, who had told him of a curious treatise 'De Motu,' which at Mr. Halley's desire he promised to send to the Society to be entered upon their register. Mr. Halley was desired to put Mr. Newton in mind of his promise for the securing this invention to himself, till such time as he could be at leisure to publish it." Early in the following year Newton sent his treatise to the Society, to whom it was read aloud by Halley. This treatise "De Motu" was the germ of the "Principia" and was intended to be a short account of what the greater work was to embrace. During the next two years Newton was hard at work on his "Principia," while Halley was equally hard at work on his computations of the Comet of 1682, and on his theory of the orbits and the periodical returns of Comets which grew out of his observations. On April 21, 1686, Halley read to the Royal Society his own "Discourse Concerning Gravity and its Properties," in which he stated that his "worthy countryman, Mr. Issac Newton, has an incomparable treatise on Motion almost ready for the press," and that the law of the inverse square "is the principle on which Mr. Newton has made out all the phenomena of the celestial motions so easily and naturally that its truth is past dispute." of his great work. The Society voted "that a letter of thanks be written to Mr. Newton and that the printing of his book be referred to the consideration of the council and that in the meantime the book be put into the hands of Mr. Halley." The truth was that the Royal Society, at that time, did not have money enough to print the book. The Society went through the empty form of "ordering" that the book be printed "forthwith," but no printer was forthcoming until Halley himself undertook the publication of the great work at his own expense. The delicacy of Halley's feeling is revealed by his correspondence with Newton, in which he informed Newton that the book had "been ordered to be printed at the Society's charge." The preliminary delay about printing he explained to Newton "arose from the President's attedence on the King, and the absence of the vice-presidents, whom the good weather had drawn out of town." Later Newton came to realize how much he owed to Halley in this matter. In his letters to Halley henceforth he always refered to his book as if it had been Halley's book. When the great work was finished at last Newton wrote to Halley under the date of July 5, 1687: "I have at length brought your book to an end, and hope it will please you." The finished work contained a note to this effect : "The inverse law of gravity holds in all the celestial motions, as was discovered also independently by my countrymen Wren, Hooke, and Halley." The book was dedicated to the Royal Society, and to it was prefixed a set of Latin hexameters addressed by Halley to the author, ending with the well known Fine: Besides being an astronomer of the first class, Halley was also a good navigator. In 1698 he was commissioned a captain in the Royal Navy and was put in command of the King's ship, "The Paramour Pink." With this vessel he set out on a long cruise to the Pacific for the purpose of making observations on the laws which govern magnetic variations. This task he accomplished in a voyage which lasted two years and extended to the fifty-second degree of southern latitude, when the ice compelled him to turn back. On the return voyage his crew mutinied and his lieutenant sided with the mutineers. Halley quelled the mutiny by sheer force of personality, and returning to England got rid of his lieutenant. The results of his voyage were published in his "General Chart of the Variation of the Compass" in 1701. Immediately afterwards Halley set out on another King's ship and executed by royal command a careful survey of the tides and coasts of the British Channel, an elaborate chart of which he published in 1702. Trieste. On Halley's return to England, he was made Savilian professor of geometry at Oxford, and received an honorary doctor's degree. He filled two terms of Royal. He died on January 14, 1742, at the age of eightyfive in the full possession of his faculties, the foremost astronomer of the day and a man universally beloved and respected. His gravestone stands at the Greenwich Observatory. Halley's works fill several shelves in the library of the Royal Society. His fame is kept green by the periodical return of the wandering star known by his name. Probably the heads are a mixture of solid and gaseous matter. The tails are gaseous — the result of the volatilisation of the solid matter of the heads. The spectroscope shows that gases appear to be a constituent of all Comets. The spectra of Comets are very similar to those of a Bunsen flame. Recent spectroscopic photographs have revealed the presence of hydrocarbons, nitro-carbons, of cyanogen and of the vapours of sodium, TforT and other metals. The connection between Comets and Meteors implies the presence in Comets of solid matter. A modern theory, voiced by Schiaparelli, is that meteor showers are broken up Comets. The tails of Comets appear to be composed of luminous gases ejected from the head of the Comet through a solar force held to be "Light Pressure," which causes these tails to shoot off and disperse into space at the rate of 865,000 miles an hour. The length of some Comets' tails has been estimated at 125,000,000 miles, while the Comets' heads themselves are generally much larger in size than our Earth. Halley's Comet, is more than ten-fold the size of our Earth. E. W. Maunder, of the Royal Observatory of Greenwich, a modern astronomer, has thus summarized the latest theories of the substance of Comets : tain some solid matter, but it is probably in the form of a loose aggregation of stones enveloped in vaporous material. There is some reason to suppose that Comets are apt to shed some of these stones as they travel along their paths, for the orbits of the meteors that cause some of our greatest 'star showers' are coincident with the paths of Comets that have been observed. But it is not only by shedding its loose stones that a Comet diminishes its bulk; it loses also through its tail. As the Comet gets close to the Sun its head becomes heated, and throws off concentric envelopes, much of which consists of matter in an extremely fine station of division : The orbits of Comets visible to human eyes are all governed by the Sun. In the words of C. L. Toor: "The attraction of the Sun is to the Comet like the flame to the moth. The Comet flutters for a moment about the Sun, and then swings back into outward space. But not unscathed ; like the moth, the Comet has been singed. The fierce light of the Sun has beaten upon it, and spread out its particles and scattered them along its path." As a comet swings toward and away from the Sun, it travels at a tremendous rate of N^geeq-— over a million miles an hour. The-jdislance covered rrom one end ot the orbit to the other is 3,370,000,000 miles. The great majority of Comets appear to travel in parabolas, open curves leading from infinite space to and around the Sun, and thence back into infinite space to some other fixed star invisible to us. As a matter of fact, though, the parabolic curves of Comets' orbits through the gravitational attraction of the planets, whose orbits are crossed by it, may be changed into hyperbolic curves and ellipses by planetary perturbations. Hence the differences in time between the returns of certain Comets, like Halley's, for instance. AWAY FROM THE SUN. In a general way, it may be said that every Comet comprises a nucleus, an envelope (called the "coma") surrounding the nucleus and measuring from 20,000 to i->ooo,ooo miles in diameter, and a long tail which streams behind the nucleus from sixty to a hundred million miles or more. Astronomers have decided that the nucleus is probably a heap of meteorites varying in size from a grain to masses weighing several tons each; a heap, moreover, so easily sundered that its 1 p™TJri .t.Ul££ ally along the orbit. It follows that every Comet must eventually perish unless it restores its nucleus by collecting stray meteors. That disintegration does occur has been observed time and time again. For example, Biela's Comet, which was discovered in 1826, burst into two fragments, which drifted apart a distance of one million miles. Thus it became a twin Comet. Eventually it disappeared as a Comet, and in its stead we see a shoal of meteors whenever we cross its track every six and a half years. It is possible that the Comets of 1668, 1843, 1880, 1882 and 1887, all travelling in approximately the same path, are fragments of a single large body which was broken up by the gravitational action of other bodies in the system, or through violent encounter with the Sun's surroundings. The luminous tail which streams behind the nucleus, which Shakespeare described so beautifully as "crystal tresses," is startling, to say the least. Despite a length which may exceed a hundred million miles, it is so diaphanously light and subtile that it is diffcult to compare it with any earthly fabric. The air that we breathe is a dense blanket in comparison. .Several hundred cubic miles of the matter composing that wonderful luminous plume would not outweigh a jarful of air. By reason ot its fairy lightness, it is possible for a tail occupying a volume thousands of times greater than the sun to sweep through our solar system without causing any perturbations in planetary movements. No celestial phenomenon has caused more perplexity than the ghostly sheaf of light we call a Cometh-tail. In a day, in a few hours even, the £omi -oi-tka.L,wonderful_ gossamer may change. Hence it is that periodic Comets are identified when they return, not by the length and arch of their tails, but by their orbits. These alone are permanent. When a Comet is first seen in the telescope, it appears as a diminutive filmy patch, often unadorned by any tail. As it travels on toward the Sun, at a speed compared with which a modern rifle bullet would seem . to crawl, violent eruptions occur in the nucleus. The ejected matter is bent back to form the cloak called the "coma." With a nearer approach to the sun, the tail begins to sprout, increasing in size and brightness as it proceeds. Evidently there is some connection between the Sun and the tail, something akin to cause and effect. When the Comet rushes on toward the Sun, invariably the tail drifts behind the nucleus like the smoke from a locomotive. But when the Comet swings around the Sun and travels away from it, a startling change takes place. The tail no longer trails behind, but projects in. front, as if some mighty solar wind were blowing it in advance of the head. This phenomenon has long been an astronomical riddle. Here was a kind of matter that, refused to obey the laws of gravitation and yield to the enormous pull of the Sun. It was thought for a time that the tail was flung away from the Sun by stupendous repelling electrical forces. That electricity plays its part in the formation of the fairy plume is conceivable, and even probable; but recently the physicist has discovered a new source of repellent energy which very plausibly explains the mystery of a Comet's tail. " This new source of energy is nothing less than the pressure or push of the Sun's light. Solar gravitation is a force more powerful than we can realize. If it were possible for us to live on the Sun, we would find ourselves pulled down so violently that our body would weigh two tons. Our clothing alone would weigh more than one hundred pounds. Running would be a very difficult athletic feat. Light pressure must indeed by powerful if it can conquer so relentless a force. Because we have never seen objects torn from our hands by the pressure of light, it may be inferred that this newly discovered force affects only bodies that are invisibly small. With the aid of instruments that feel what our hands can never feel and see what our eyes can never see, the modern physicist has critically analyzed the radiation that beats upon the earth from the distant Sun. Light really does sway infinitely small particles, as was first experimentally proved by the Russian Lebedev. Two American astronomers, Nichols and Hull, improved upon his method. They cast the solar effulgence into mighty mathematical scales and found that the earth sustains a light-load of no less than 75,000 tons. Most city-bred people are familiar with the so-called "Sun Motors" — little mills with black and white wings, enclosed in airtight vessels, which spin around in "perpetual motion" under the effect of "Sun Pressure." It remained for the broad mind of a Swedish physicist, Svante Arrhenius, to apply the principle of light-pressure cosmically. He explained, very simply, that because-, a^ Comet's tail is composed, of a very fine dust it can easily be driven away from the Sun by radiation pressure. To understand how it is possible for so immaterial a thing as a sunbeam to produce so huge art effect, we have only to take a very simple example. Assume that you have before you a block of wood weighing one pound. The block exposes a certain amount of surface to the Sun's light. Saw the block in half, and you increase the amount of that surface. Divide each half again into half, and the exposed surface is further augmented.r If this process of subdivision is carried on far enough, the block will be reduced to sawdust. The entire mass of sawdust still weighs one pound; but its surface has been vastly enlarged. Indeed, the particles of sawdust, individually considered, may be said to consist of much surface and very little weight. If it were possible to take each granule of visible sawdust and subdivide it into invisible particles, a -peiot-jaziuild be reached whej^^he_pressure of light would exactly coun> terbalance the pull of gravitation, so that the particles. /\ jEVQuIH remain suspendeH^TrT space, perfectly balanced in the scale of opposing cosmic forces. „ Finally, if the subdivision be continued beyond this critical point, the particles will be wrenched away from the grip of gravitation and hurled out into space by the \ pressure of light. ^£o much has been discovered about the particles that compose a Comet's tail that the more progressive scientists of our day have accepted this ingenious theory. Thus it has been decided by them that the delicate tresses CHANGES IN THE COMET OF 1863. Before we can completely accept the view that lightpressure forms this train of soot we must ascertain whether the pressure of light is capable of accounting for the flash-like rapidity with which a Comet's tail changes. A .Comet may throw out a tail sixty million miles long in t\yo days.. Is it actually possible for light-pressure to accomplish that astonishing feat? Arrhenius has computed that 865,000 miles an hour is the speed of a lightflung particle of one-half the critical diameter. Because they are, only one-eighteenth as large as this particle of critical diameter, the dust grains in a Comet's tail would be propelled over the same 865,000 miles in less than four minutes. It follows that the solar radiation is amply strong enough to toss out a tail of sixty million miles in two days. Photography in the hands of Prof. E. E. Barnard, of the Yerkes Observatory, has revealed some extraordinary changes in Comets' tails, changes which are not apparent to the eye and which cannot be explained by light pressure or by solar electrical forces. He has collected a formidable mass of photographic evidence which seems p-o show that there are other influences at work besides \ the Sun's radiation, and that these influences manifest 1 themselves in distorting and breaking a Comet's tail. In '-some Comets of recent years, streams of matter have been shot out in large angles to the main direction of the tail without being at all bent by the pressure of light. In Morehouse's Comet of 1908, tails were repeatedly formed and discarded to drift bodily out into space and melt away. Sometimes the photographic plate has shown the tail twisted like a corkscrew and sometimes it has revealed masses of matter at some distance from the head, where apparently no supply had reached it. At one time the entire tail of Morehouse's Comet was thrown vio- lently forward, a peculiarity so utterly opposed to the laws of gravitation that Professor Barnard suspects some unknown force at work in planetary space besides a force which undoubtedly resides in the Comet itself. If Halley's Comet serves no other purpose than to throw light upon this mystery, its return will more than repay astronomers for all their observatory vigils. From the fact that the matter is ejected from the head to form the tail, it would follow that, unless it has the means of rejuvenating itself, a comet must eventually be disintegrated. Instances. .a£-~this~ .fragmfaita.tio.n .._and^ eventual disappearance of a Comet are not wanting in astronomical annals. It has been stated previously that when Biela's Comet appeared in 1846 it became distorted and elongated, that it eventually split up into two separate bodies, that in 1852 it again appeared in its double form, and that it has since disappeared. In a way, Comets may be said to bleed to death. At each return of Halley's Comet, future astronomers will find it less brilliant than it was seventy-six or seventyseven years before. Some time there will be no Halley's / Comet left, and the most famous Comet of its kind will be reduced to a shoal of meteors varying in weight from a few ounces to several tons and faithfully pursuing the orbit which their parent traced and retraced century after century. stition had never dreamed. While he was patiently_plQt±ing__oiit_±lie_Drbit of the Comet of 1680, which had inspired no little dismay among his contemporaries, Halley found that the Earth's orbit had been approached by the Comet within four thousand miles — half the diameter -of the Earth. None had ever thought of the possibility. Halley began to do some mathematical figuring, and decided that, if a Comet's mass were comparable with that of the Earth, our year would have been changed in length because the Earth's orbit would have been altered. He also speculated what would happen to the Earth, and reached this conclusion : "If so large a body with so rapid a motion were to strike the Earth — a thing by no means impossible — the shock might reduce this beautiful world to its original chaos." Halley even thought it probable that the Earth had actually been stryck by a Comet at some remote period, struck obliquely, moreover, so that the axis of rotation had been changed. Thus he was led to infer that possibly the North Pole had once been at a point near Hudson's Bay, and that the rigour of North America's climate might thus be accounted for. lision with a Comet. Dr. Whiston, who succeeded Newton at Cambridge in the Lucasian chair of mathematics, was sure that a Comet caused the Deluge, and went so far as to prophesy that a Comet, as it passed us on its outward course from the Sun, would ultimately bring about a "General Conflagration," and thus envelope the Earth in flames. One century after Halley, the French astronomer Laplace, whose mathematical attainments were surpassed only by those of Newton, applied his brilliant mind to the possibility of a collision with a Comet, and arrived at this conclusion: "The seas would abandon their ancient beds and rush towards the new equator, drowning in one universal deluge the greater part of the human race. . . . We see, then, in effect, why the ocean has receded from the high lands upon which we find incontestable marks of its sojourn; we see how the animals and plants of the south have been able to exist in the climate of the north, where their remains and imprints have been discovered." The famous French mathematician Lalande showed that if a Comet as heavy as the Earth were to come within six times the distance of the Moon, it would exert such a powerful attraction upon the waters of the globe as to pull up a tidal wave 13,000 feet above the ordinary sea-level and inundate the continents. .Every European mountain would be submerged except Mt. Blanc, and only the inhabitants of the Rockies, the Andes and the Himalayas would escape death. Since Lalande's day there has been more than one Comet "scare." One of these startled Europe in 1832. On October 2Qth of that year, Biela's Comet crossed the Earth's orbit. The announcement was received with stupefaction. It was only when Arago soothingly pointed out that the Earth would not reach the exact point where the Comet had intersected the Earth's orbit until November 30, at which time the Comet would be 50,000,000 miles away, that the popular excitement subsided. A similar alarm seized the world in 1857. Some prophet declared that on June 13 the world would collide with a certain periodic Comet having a period of revolution of three centuries. It is related that the churches and confessionals were crowded for days. Still another prediction, made in 1872 by Plantamour, the distinguished director of the Geneva Observatory, set Europe in a ferment. His calculations were based on errors, which were pointed out by other astronomers, and the public mind was quieted. Although more than two centuries have passed since Halley was in his prime, the possibility of a collision with some vagabond star still haunts the mind of the astronomer. That a collision is apt to occur is an admitted astronomic fact. The latest estimate, made in 1909 by Prof. William H. Pickering of Harvard University, would seem to prove that the core of one Comet in about 100,000,000 Comets will hit the earth squarely An encounter with some part of a Comet's head wil happen once in 4,000,000 years. Since Comets' orbit are more thickly distributed near the ecliptic than else where in the celestial sphere, the collisions will occur according to Pickering, perhaps more frequently tha. this. Because Pickering's figures differ from those other astronomers — Arago and Babinet, for instance — it must not be inferred that his predecessors are wrong and that he is right in his calculations. The problem is too complex for that. Pickering, Arago and Babinet differ partly because they have assumed different average sizes for their Comets, and partly because their definitions of visible Comets are not in accord. That the possibility is very real, we shall all have an opportunity of judging on May 18, 1910. On that date the Earth will be plunged in the tail of Halley's Comet, and the head will be less than 15,000,000 miles away — a mere hand's breadth in the vastness of the universe. Nobody knows for certain. By means of the wonderful instrument called the spectroscope, an instrument which analyzes a distant star as readily as if it were a stone picked up in the road, it has been discovered that a Comet's tail is composed of gases called "hydrocarbons" (combinations of hydrogen and carbon), and that it bears a close chemical resemblance to the blue {Tame of a kitchen gas-stove. Illuminating gas, as we all know, is poisonous. If a Comet's tail were dense enough, it is conceivable, therefore, that every human being on this planet might be asphyxiated by breathing the Comet's poisonous vapour as the Earth plowed through it. There is also this possibility, suggested by Flammarion, that the gases of a very dense tail might so combine with the nitrogen which constitutes nearly 80 per cent, of the air we breathe, that the atmosphere would be converted into the "laughing gas" employed by dentists. The world would die in a delirium of joy. At first a delightful serenity would settle upon mankind. Then would follow a contagious gaiety, febrile exaltation, a paroxysm of delight, and then madness. Flammarion even conceives the world merrily" dancing a joyous, hysterical sarabande in which it perishes laughing. The tail of a Comet is fraught with still other possible dangers. Our atmosphere contains a certain amount of hydrogen, a marvellously light gas to which balloons owe their buoyancy. Besides its lightness, this gas is characterized by an extreme inflammability. The law of the diffusion of gases teaches us that part of this hydrogen in the air is mechanically mixed with other gases, and that part of it probably floats in the upper air, far beyond the reach of any balloon. A Comet may be regarded as a huge lighted torch whirling through space, which may be brought dangerously near that upper layer of highly inflammable hydrogen. If the gas shall ever be touched off by this flying torch, our planet will be ignited. The whole atmosphere will become a seething ocean of flame, in which forests and cities will burn like straw, in wrfich oceans will boil away in vast clouds of steam, and in which all animal life will be snuffed out of existence before it shall realize that the world is on fire. In a word, the globe will become a planetary funeral pyre. Since water results from burning hydrogen in oxygen, this same fierce and terrible flame must be speedily extinguished by a mighty deluge which will engulf the Earth. A spectroscope analysis of Halley's Comet has furthermore revealed the presence of ryan^g^n g?? ln tb6 tail. Cyanogen is a compound of -nitrogen and carbon, one of the most poisonous compounds with which the chemist is familiar. Prussic acid, potassium cyanide and many other cyanides, all of them almost instantaneously fatal if taken into the human system, are compounds of cyanogen. If that gas is present in large enough quantities, one flick of a Comet's tail will end all human and animal existence. trous will depend largely on the size of the Comet's head and on its speed. That a violent heat will be developed, we have every reason to believe, from our knowledge of meteors. The mere movement of a meteor through the thin upper layers of our atmosphere produces a dazzling trail and reduces the meteor itself to a molten metallic mass. Arrest a body in swift motion, and you must dissipate its energy in some way. As a rule, the energy is converted into heat. A bullet discharged from a rifle is often melted when suddenly stopped by steel armour. A Comet travels at a pace compared with which a projectile, fired from the most powerful twelve-inch gun, seems only to crawl. What, then, must be the frightful effect when it strikes the Earth? A Comet rushes through space not at' the bullet's rate of thousands of feet an hour, but of a million miles an hour. The bigger it is, and the faster it moves, the greater will be the heat developed by its stoppage. "At the first contact with the upper regions of the atmosphere," writes Prof. Simon Newcomb, "the whole heavens would be illuminated with a resplendence beyond that of a thousand Suns, the sky radiating a light which would blind every eye that beheld it, and a heat which would melt the hardest rocks." The same conclusion was reached by Prof. Faye. When the time comes for a collision with a Comet of formidable size, the human race will be in the horrible predicament of knowing the exact hour and minute of its doom. The newspapers will print a dispatch from some great observatory, reading perhaps like this : "A telescopic Comet was discovered by Caxton in right ascension 7 hours 13 minutes i second, and declension 17 degrees 28 minutes 31 seconds. Moderate motion in a northwest direction." "If so large a body with so rapid a motion were to strike the Earth — a thing by no means impossible— the shock would reduce this beautiful world to its original chaos." — -EDMUND HALLEY. At first -the discovery produces not even a ripple of excitement. Telescopic Comets are discovered too frequently. Three days later the discoverer has worked out an ephemeris, which gives the date when the body will pass around the Sun, and which indicates the Comet's path. He finds that on a certain date and at a certain hour the Earth and the Comet must crash together. Again and again he repeats his calculations, hoping that he may have^rred. The utmost permissible allowance for accelerations and retardations caused by the outer planets of the solar system fails to change the result. The Earth and the Comet must meet. With some hesitation the astronomer sends a telegram to a central observatory, which acts as a distributor of astronomical news. At first his prediction is discredited and even laughed at. Another computation is made at the observatory. Again mathematics infallibly indicates the exact time and place of the encounter, and the last lingering hope is dispelled. Telegrams are sent to astronomical societies, to the leading scientific periodicals and to the newspapers. At first the prediction of the Earth's doom is received with popular incredulity, engendered by years of newspaper misrepresentation. The world's end has been too frequently and too frightfully foretold on flamboyant double-page Sunday editions. When the truth is at last accepted, after days of insistent repetition of the original announcement, a wave of terror runs through the world. There is no escape. International committees of astronomers meet daily to mark the approach of the Comet. Bulletins are published announcing the steadily dwindling distance between the world and the huge projectile in the sky. The great tail, arching the Heavens as the Comet approaches, seems like a mighty, fiery sword held in an unseen Titanic hand and relentlessly sweeping down. The temples, churches and synagogues are thronged with supplicating multitudes on bended knees, in a catalepsy of terror. The stock exchanges, banks, shops and public institutions are deserted. Business is at a standstill. The roar of the street is hushed. No wagons rattle over the pavement; no hucksters call out their wares. As the Comet draws nearer and nearer, night changes into an awful, nocturnal day. Even at noon the Comet outshines the Sun. There is no twilight. The Sun sets; but the Comet glows in the sky, another more brilliant luminary, marvellously yet fearfully arrayed in a fiery plume that overspreads the sky. The Moon is completely lost, and the Stars are drowned out in this dazzling glare. Warned by the astronomers, mankind takes refuge in subterranean retreats to await its fate. Long before the actual collision — long before the Earth is reduced to a maelstrom of lava, gas, steam and planetary debris — mankind is annihilated with merciful swiftness by heat and suffocation. A candle flame blown out by a gust of wind is not more quickly extinguished. When the Comet encounters the upper layers of the atmosphere, there is a blinding flash, due to friction between the air and the Comet. A few seconds later the crash comes. From within, molten rock and flame, pent up for geologic ages, burst forth, geyser-like. The Earth is converted into a gigantic volcano, in the eruption of which oceans are spilled and continents are torn asunder, to vanish like wax in a furnace. THE END OF THE WORLD /^AMILLE FLAMMARION, the French astrono^^ mer, in his story, uThe End of the World," gives this graphic description of the results of a collision between a Comet and our Earth: In Paris, London, Rome, Berlin, St. Petersburg, Constantinople, New York and Chicago — in all the great capitals of the world, in all the cities, in all the villages — the frightened people wandered out of doors, as one sees ants run about when their ant-hills are disturbed. All the affairs of every-day life were forgotten. All human projects were at a standstill. People seemed to have lost interest in all their affairs. They were in a state of demoralization — a dejection more abject even than that which is produced by sea-sickness. had become inevitable. In Paris the crowds in the churches were so great that people could no longer get near Notre Dame, the Madeleine and the other churches. Within the churches, vast congregations of worshippers were on their knees praying to God on High. The churches rang with the sounds of supplication, but no other sound was heard. The great church organs and the bells in the steeples were hushed. In the streets, on the avenues, in the public squares, there was the same dread silence. Nothing was bought or sold. No newspapers were hawked about. The only vehicles seen on the streets were funeral hearses carrying to the cemeteries the bodies of the first victims of the Comet. Of these there were already To the solar day succeeded a new day, the daylight of the Comet. Its intense light resembled that of an Aurora Borealis, but more vivid, coming from a great incandescent spot, which had not been visible during the day because it was below the horizon, but which would certainly have rivalled the splendour of the Sun. This luminous spot rose in the East almost at the same time as the full Moon. The two luminous bodies rose together, side by side. As they rose, the light of the Moon seemed to pale, but the head of the Comet increased in splendour with the disappearance of the Sun below the western horizon. Now, after nightfall, the Comet dominated the world — a scarlet-red ball with jets of yellow and green flame which seemed to flutter like fiery wings. as from a vast fire. An instant afterward, the Comet diminished in brilliancy. This was apparently because the Comet, upon touching the atmosphere of our Earth, had come within the penumbra of our planet and had lost part of its reflected light coming from the Sun. But in reality this apparent extinction was the effect of contrast. When the less dazzled eyes of the awestruck, human spectators had grown used to this new light, it appeared almost as intense as at first, but paler, more sinister and sepulchral. a light. The drouth of the air became intolerable. Heat, as from a huge burning oven, came from above. A horrible stench of burning sulphur — due, no doubt, to electrified ozone — poisoned the atmosphere. is burning. they cried. All the horizon, in fact, was now lit up with flame, forming a crown of blue light. It was, indeed, as had been foreseen by scientists, the oxide of carbon igniting in the air and producing anhydrid of carbon. Clearly, too, hydrogen from the Comet combined with it. On a sudden, as the people were gazing terrified, motionless, mute, holding their breath, and scared out of their wits, the vault of Heaven seemed to be rent asunder from the zenith to the horizon. Through the gaping breach there seemed to appear the huge red mouth of a dragon, belching forth sheaves of sputtering green flames. The glare of the atmosphere was so fierce that those who had not already hidden themselves in the cellars of their houses, now all rushed helter-skelter to the nearest underground openings, be they subway steps, cellar doors or sewer manholes. Thousands were crushed or maimed during this mad stampede, while many others, frantic from fright and stricken with the heat, fell dead from apoplexy. All reasoning powers seemed to have ceased. Among those cowering in dark cellars and subterranean passages below, there was nothing but silence, begot by dull resignation and stupor. Of all this panic-stricken multitude, only the astronomers had remained at their posts in the Observatories, making unceasing observations of this great astronomic phenomenon. They were the only eye-witnesses of the impending collision. Their calculations had been that the terrestrial globe would penetrate into the core of the Comet, as a cannon ball might into a cloud. From the first contact of the extreme atmospheric zones of the Earth and of the Comet, they had figured, the transit would last four hours and a half. It was easy to compute, since the Comet, being about fifty times as large -as the Earth, was to be pierced, not in its centre, but at one-quarter of the distance from the centre, with a velocity of 173,000 kilometers an hour. It was about forty minutes after the first atmospheric impact with the Comet, that the heat and horrible stench of burning sulphur became so suffocating that a few more moments of this torment would put an end to all life. Even the most intrepid of astronomers withdrew into the interior of their glass-domed observatories, which they could close hermetically as they descended into the deep subterranean vaults. The longest to stay above was a young assistant astronomer, a girl student from California, whose nerves had been steeled during the ordeal of the San Francisco earthquake. She remained long enough to witness the apparition of a huge, white-hot meteorite, precipitating itself southward with the velocity of lightning. oxide of carbon. The ears rang as from the tolling of funeral bells, and all hearts were in a flutter of feverish palpitation. And always, everywhere, there was that suffocating stench of sulphur. Now a shower of fire fell from the glowing sky. It was raining shooting-stars and white-hot meteorites, most of which burst like bombs. The fragments of these, like flying shrapnel, crashed through the roofs and set fire to the buildings. of fire everywhere on earth. Claps of ear-splitting thunder followed each other incessantly, produced partly by the explosions of the meteors, and partly by a tremendous electric thunderstorm. Rifts of lightning zig-zagged hither and thither. A continuous rumbling, like that of distant drums, filled the ears of the cowering people below, awaiting their fate. This low rumble was interspersed with the deafening detonations of exploding meteors and the high shriek of hurtling aerial fragments. Then followed unearthly noises, like the seething of some immense boiling cauldron, the wild wailing of winds, and the quaking of the soil where the earth's crust was giving way. This unearthly tempest became 30 frightful, so fraught with agony and mad terror, that the multitudes grovelling below were overcome with paralysis, and lay prone.	29,224	common-pile/pre_1929_books_filtered	cometlorehalleys00emerrich	public_library	public_library_1929_dolma-0005.json.gz:3335	https://archive.org/download/cometlorehalleys00emerrich/cometlorehalleys00emerrich_djvu.txt
rTjBk9Xc16TfIDf2	Art Appreciation	58 Reading: Romanesque The name gives it away–Romanesque architecture is based on Roman architectural elements. It is the rounded Roman arch that is the literal basis for structures built in this style. All through the regions that were part of the ancient Roman Empire are ruins of Roman aqueducts and buildings, most of them exhibiting arches as part of the architecture. (You may make the etymological leap that the two words are related, but the Oxford English Dictionary shows arch as coming from Latin arcus, which defines the shape, while arch-as in architect, archbishop and archenemy-comes from Greek arkhos, meaning chief. Tekton means builder.) When Charlemagne was crowned Holy Roman Emperor in 800 C.E., Europe began to take its first steps out of the “Dark Ages” since the fall of Rome in the fifth century. The remains of Roman civilization were seen all over the continent, and legends of the great empire would have been passed down through generations. So when Charlemagne wanted to unite his empire and validate his reign, he began building churches in the Roman style–particularly the style of Christian Rome in the days of Constantine, the first Christian Roman emperor. After a gap of around two hundred years with no large building projects, the architects of Charlemagne’s day looked to the arched, or arcaded, system seen in Christian Roman edifices as a model. It is a logical system of stresses and buttressing, which was fairly easily engineered for large structures, and it began to be used in gatehouses, chapels, and churches in Europe. These early examples may be referred to as pre-Romanesque because, after a brief spurt of growth, the development of architecture again lapsed. As a body of knowledge was eventually re-developed, buildings became larger and more imposing. Examples of Romanesque cathedrals from the early Middle Ages (roughly 1000-1200) are solid, massive, impressive churches that are often still the largest structure in many towns. In Britain, the Romanesque style became known as “Norman” because the major building scheme in the 11th and 12th centuries was instigated by William the Conqueror, who invaded Britain in 1066 from Normandy in northern France. (The Normans were the descendants of Vikings – Norse, or north men – who had invaded this area over a century earlier.) Durham and Gloucester Cathedrals and Southwell Minster are excellent examples of churches in the Norman, or Romanesque style. The arches that define the naves of these churches are well modulated and geometrically logical – with one look you can see the repeating shapes, and proportions that make sense for an immense and weighty structure. There is a large arcade on the ground level made up of bulky piers or columns. The piers may have been filled with rubble rather than being solid, carved stone. Above this arcade is a second level of smaller arches, often in pairs with a column between the two. The next higher level was again proportionately smaller, creating a rational diminution of structural elements as the mass of the building is reduced. The decoration is often quite simple, using geometric shapes rather than floral or curvilinear patterns. Common shapes used include diapers – squares or lozenges – and chevrons, which were zigzag patterns and shapes. Plain circles were also used, which echoed the half-circle shape of the ubiquitous arches. Early Romanesque ceilings and roofs were often made of wood, as if the architects had not quite understood how to span the two sides of the building using stone, which created outward thrust and stresses on the side walls. This development, of course, didn’t take long to manifest, and led from barrel vaulting (simple, semicircular roof vaults) to cross vaulting, which became ever more adventurous and ornate in the Gothic.	806	common-pile/pressbooks_filtered	https://library.achievingthedream.org/herkimerartappreciation/chapter/reading-romanesque/	pressbooks	pressbooks-0000.json.gz:74238	https://library.achievingthedream.org/herkimerartappreciation/chapter/reading-romanesque/
oTApz0HrQ9RU9GqZ	9.2: MSA Media Procedure	9.2: MSA Media Procedure MSA Media Procedure Name: _____________________________________________________ Course Section: ______________________________________________ The following activity will teach students how to inoculate an MSA plate. Post-inoculation, students will use their colony growth to determine if the bacteria are halophilic and verify mannitol utilization. \| Materials \| \| \| Procedure \| \| Step 1: \| \| \| Step 2: \| \| \| Step 3: \| \| \| Step 4: \| Results In the table below, record your observations for colonies grown in MSA media. \| Species \| Growth (+/-) \| Salt resistance (+/-) \| Medium color surrounding growth \| Mannitol fermentation (+/-) \| \|---\|---\|---\|---\|---\| \| Staphylococcus saprophyticus \| \| \|\|\| \| Staphylococcus epidermidis \| \| \|\|\| \| Escherichia coli \| \| General Questions 1. Define selective medium. 2. Explain how MSA is a selective medium. 3. Define differential medium. 4. Explain how MSA is a differential medium. 5. Explain how phenol red, a component of MSA, detects if a species conducts mannitol fermentation. 6. Explain the role of MSA in differentiating between commensal skin flora and potentially pathogenic bacteria present in clinical samples obtained from skin infections. Health-Related Questions 1. Mannitol salt agar plates are used to differentiate between bacteria that belong to what genus? 2. What bacteria causes MRSA? 3. Why is MRSA a significant concern for healthcare workers? 4. How do we use mannitol salt agar to determine if a patient is infected with S. epidermidis or S. aureus?	310	common-pile/libretexts_filtered	https://bio.libretexts.org/Courses/Horry-Georgetown_Technical_College/HGTC_BIO_225%3A_Microbiology_Lab_Manual/09%3A_Biochemical_Characterization_Part_I/9.02%3A_MSA_Media_Procedure	libretexts	libretexts-0000.json.gz:39958	https://bio.libretexts.org/Courses/Horry-Georgetown_Technical_College/HGTC_BIO_225%3A_Microbiology_Lab_Manual/09%3A_Biochemical_Characterization_Part_I/9.02%3A_MSA_Media_Procedure
BI5lzmBt1yYXIktg	5.14: Semicolons- The Connectors	5.14: Semicolons- The Connectors - Demonstrate the standard uses of semicolons Semicolons serve as connectors in two ways: connecting two complete ideas and to separate items in a list. Connecting Two Independent Clauses First, a semicolon can connect two complete ideas (a complete idea is an independent clause, which has a subject and a verb and can stand on its own as a sentence) that are related to each other and/or equal. Look at this sentence for example: - Anika’s statue is presently displayed in the center of the exhibit; this location makes it a focal point and allows it to direct the flow of visitors to the museum. The first idea tells us where Anika’s statue is, and the second idea tells us more about the location and its importance. Each of these ideas could be its own sentence, but by using a semicolon, the author is telling the reader that the two ideas are connected. Often, you may find yourself putting a comma in the place of the semicolon; this is incorrect. Using a comma here would create a run-on sentence. Remember: a comma can join a complete idea to other items while a semicolon needs a complete idea on either side. Here are a few more examples: - I had a salad for lunch; I wasn’t all that hungry. - Joe went to the soccer field; Amanda decided to go to the library. Both of these sentences have two connected independent clauses that could both stand alone as individual sentences. The following sentence, however, has one independent clause and one dependent clause, so it would require a comma instead of a semicolon to join the two ideas: - Emojis are fun to text with, because I can show how I’m really feeling. Semicolons also serve to separate items in a list, such as in a list of places or a list of duties on a résumé: As a photographer for National Geographic, Renato had been to a lot of different places including São Paulo, Brazil; Kobe, Japan; Kyiv, Ukraine; and Barcelona, Spain. As an engineering assistant, I had a variety of duties: participating in pressure ventilation surveys; completing daily drafting, surveying, and data compilation; and acting as a company representative during a roof-bolt pull test. Contributors and Attributions - Semicolons. Provided by : Lumen Learning. License : CC BY: Attribution - Image of the Golden Gate Bridge. Authored by : Free-Photos. Provided by : Pixabay. Located at : pixabay.com/photos/golden-gate-bridge-san-francisco-388917/. License : Other . License Terms : pixabay.com/service/terms/#license	546	common-pile/libretexts_filtered	https://human.libretexts.org/Courses/Lumen_Learning/English_Composition_I_(Lumen)/05%3A_Grammar_Essentials/5.14%3A_Semicolons-_The_Connectors	libretexts	libretexts-0000.json.gz:34434	https://human.libretexts.org/Courses/Lumen_Learning/English_Composition_I_(Lumen)/05%3A_Grammar_Essentials/5.14%3A_Semicolons-_The_Connectors
kt-bIApl3k7FUJNZ	9.8: Spotlight on ... Business and Law	9.8: Spotlight on ... Business and Law By the end of this section, you will be able to: - Identify factors that influence the ways that work is designed, documented, and disseminated. - Apply methods and technologies commonly used for communication in various fields. - Write an effective résumé and accompanying cover letter. - Interpret legal language and rewrite it in plain English. In the business and legal worlds, written and spoken rhetoric is crucial to successful outcomes and the internal workings of an organization. Rhetoric in Business The ability to write persuasively by using rhetorical strategies is crucial to the success of a business, including its profitability, employee satisfaction, and efficient operations. The purpose of business writing is often to sell, whether an idea, a candidate, a product, or a strategy. For most people, the first step in business writing is an effective application letter and résumé with the goal of obtaining an interview. Figure $9.7$ A strong cover letter and résumé will impress prospective employers, who will be well disposed toward interviewing you. Remember the purpose of these written pieces is to obtain an interview, not the job—at least not yet. (credit: “Women in Tech - 82” by WOCinTechChat.com/flickr, CC BY 2.0) Application Letters and Résumés When writing letters of application and résumés, keep in mind that you are writing to sell. In this case, you need to “sell” yourself to a company. Thus, you want to convey information rhetorically and persuasively. The most effective application letters have one element in common: they focus as much as possible not on you, the applicant, but on the company and the ways in which you could be an asset as an employee. Therefore, keep in mind that your need for work is not a real concern to a prospective employer. Rather, their needs and your potential are. If you are applying for a job, ask yourself these questions: What can you do to fill a present or future need? What exactly is the employer looking for (as opposed to what you are looking for)? If an employer has indicated criteria for applicants, what are those criteria, and how can you show you fulfill them? Keep these ideas in mind when writing an application letter. Because you are focusing on your value to a company, do not start like this student did: My name is Brett Ellison. I am graduating this spring and would like to apply for the position you have advertised. It looks interesting and would suit me well. It will take exciting and convincing writing to build interest after such a generic introduction. Your name, graduation date, and opinion of the job are of little interest to a future employer. Consider the difference with this opening: For the job opening you have advertised online in data management, you have asked for a recent graduate with skills in. . . . Four years of college with a major in computer science and an internship with Coverall Insurance have given me the skills you require. The applicant mentions the required skills and follows with a statement indicating they possess the skills. When you begin this way, you emphasize the company’s needs, not your own. The first paragraph should then end with a statement that you are attaching your current résumé and that you request the company’s consideration. In the next paragraph, highlight a specific achievement connected to that skill and your abilities. Include other aspects of your background as relevant. Try to keep each paragraph to no more than six lines. If possible, continue to focus on the company and its needs, showing that you know something about them. Keep it short; one page will be sufficient to highlight your skills. Avoid mentioning areas of weakness or skills you do not have. Conclude with an expression of gratitude for their consideration. If you have a recommendation or lead for the job, you can naturally begin with that, as this student did in the following letter: A current résumé should always accompany your application letter. Try to tailor your résumé to highlight unique credentials you may have and ones that may set you apart from other applicants. Your résumé should complement the letter, meaning the two parts should fit together and not contradict each other. A good idea is to edit the résumé to fit the job you want by adding or highlighting parts that pertain specifically to the position; changing the order of details; or using italics, boldface type, or bullets for listing facts or dates. The résumé should not be a one-size-fits-all product or give the impression that it is a standard statement with no real pertinence to the specific job. Use your résumé as a selling tool to persuade a company or organization to grant you an interview. Actually getting the job comes later. A key element in any résumé, following your identifying information, is a statement of your career goal. Although it is inevitable that others will have similar plans, try to stand out by sounding decisive or presenting a vision of what you can accomplish. Imagine being the reader of your résumé rather than the writer. That person may devote only seconds to skimming it, and the first thing they will notice is the career goal, which you can change each time you send out a résumé. Your personal aim or goal gives you the chance to indicate something in one line that would make the reader want to continue. The following are effective statements: - To use my programming skills to create innovative and useful content for a growing company - To use what I have learned in management classes for the progress of a growing firm - To contribute to a sales force based on best practices of marketing - To work in the public sector for personal as well as social progress - To combine a productive work ethic with openness to change and travel Sample Résumé Below is Mikaela Rodgers’s résumé: Previewing a wide variety of sample résumés ( https://openstax.org/r/sample ) will give you plenty of ideas. Language in Law In the legal world, communication is equally or even more crucial. In addition to the ability to speak convincingly, the ability to use rhetorical strategies to write persuasively is of critical importance in legal professions and in everyday situations regarding disputes, contracts, and other matters involving legalities. In courtrooms and behind the scenes, the ability to persuade a judge to make a decision or ruling in favor of a particular client before or during a trial affects all aspects of a case, including the legal team’s ability to persuade a jury of its position. Furthermore, disputes between family members, buyers and sellers, renters and landlords, and employees and managers are often settled with the help of appropriately used rhetorical strategies. Figure $9.8$ Because contracts and similar binding agreements feature in many legal disputes, it is important to understand and interpret the language in which they are written. Arguing for your interpretation involves the use of rhetorical strategies. (credit: “Legal Contract & Signature - Warm Tones” by Blogtrepreneur [howtostartablogonline.net/legal]/Wikimedia Commons, CC BY 2.0) Language use in the legal profession relies on precedent , meaning evidence or examples of past legal cases and their verdicts. Legal English aims to be consistent, complete, valid, and formal. It must correspond to what is expected by the court to which it will be communicated. Legal briefs, for example, are documents written to persuade the court to agree with the writer’s position, whether for a plaintiff or a defendant. To gain judicial agreement, legal language must avoid open-ended interpretations because ambiguity (two valid points of view without a single resolution) is counterproductive. Instead, lawyers and those who write for them often adapt a writing template already familiar to and required by a court. American legal English has its roots in history. It was adopted from England, where Roman rulers and later French invaders left an inheritance of terminology still used today. Many familiar legal terms are hundreds of years old. For example, the verb shall replaces must or have to (“The plaintiff shall . . .”). The word is an imperative, binding and unconditional, unlike its uncertain use in modern English (“Shall I do that?”). Antiquated expressions appear frequently— heretofore, forthwith, until such time that, party of the first part, party of the second part, due process —as do Latin expressions— pro bono, pro se, ad hoc, bona fide, de facto . Doubling of concepts is also common: null and void, breaking and entering, pain and suffering, legal and binding. However, the linguistic situation has changed somewhat with the move toward “plain English,” meaning avoidance of the jargon and excesses of legal writing. Rather than long sentences and paragraphs with minimal punctuation and spacing of text, “plain English” reforms and simplifies the terminology to make it readily understandable for people outside the legal profession. Plain English “Plain English” was formally introduced in the United States in 2010 by President Barack Obama in the official Plain Writing Act of 2010 adopted by Congress. It was part of a paperwork reduction program extending to all areas of government communication with the goal of reducing the amount of written communication issued by all agencies. Common opinion recognized that what needed to be said could be done more efficiently if people understood the content of laws and regulations. As an example, the following regulations from the New Jersey state office for overseeing real estate transactions are unclear and confusing. Despite the capital letters, the text consists of long, dense paragraphs that actually discourage reading and understanding. Because a situation in which someone breaks a lease is likely to be stressful, language such as this, with long sentences and legal terms, only worsens the possible confrontation. The assumption is that the tenant will have to either wade through the language independently or rely on a lawyer as a paid guide. On the other hand, the following document explains in plain English, with short sentences and paragraphs, the procedures for securing federal student aid. Not only are the instructions clear, but they also explain some of the reasoning for them. The plain language of this document aims to make information easily comprehensible. It is broken into brief, concise paragraphs with short, clear sentences. Punctuation is basic and emphatic. Students already uncertain about financial security are made to feel welcome and have the sense that the procedure can be done without their becoming mired in dense language and regulations. Your Turn Business. If you have a résumé, update and revise it according to the suggestions presented in this section. If you do not have a résumé, now is the time to create one. Select a format and complete it with your information, including a professional objective. (You can access the site ( https://openstax.org/r/site ) provided earlier in this section or consult Microsoft Word for résumé templates.) Once you have revised or completed your résumé, find an announcement about a summer job or internship and write an appropriate application letter. Legal. With the Plain Writing Act of 2010 in mind, rewrite the section of the New Jersey rental agreement reproduced in this section. Change sentence and paragraph length when appropriate to simplify language and clarify meaning. Remember that your readers consist of average people looking to rent an apartment.	2,460	common-pile/libretexts_filtered	https://human.libretexts.org/Bookshelves/Composition/Introductory_Composition/About_Writing_Guide_with_Handbook_-_A_textbook_for_English_Composition_(OpenStax)/09%3A_New_Page/9.8%3A_Spotlight_on_..._Business_and_Law	libretexts	libretexts-0000.json.gz:13402	https://human.libretexts.org/Bookshelves/Composition/Introductory_Composition/About_Writing_Guide_with_Handbook_-_A_textbook_for_English_Composition_(OpenStax)/09%3A_New_Page/9.8%3A_Spotlight_on_..._Business_and_Law
uWaA4zS8fESHfeDY	2.2: Introduction to Psychodynamic Theories	What you’ll learn to do: use psychodynamic theories (like those from Freud and Erikson) to explain development Many people sometimes feel intimidated by theory; even the phrase, “Now we are going to look at some theories…” may elicit some blank stares or yawns. But, don’t tune out quite yet! Theories are valuable tools for understanding human behavior; they are proposed explanations for the “how” and “whys” of development. In this first section, we’ll examine some of the most persistent theories, developed by Sigmund Freud over a hundred years ago. While some of Freud’s ideas have since been debunked, others have lasted and continue to shape the way we think about development. Contributors and Attributions CC licensed content, Original - Introduction to Psychodynamic Theories. Authored by : Sonja Ann Miller for Lumen Learning. Provided by : Lumen Learning. License : CC BY: Attribution CC licensed content, Shared previously	191	common-pile/libretexts_filtered	https://socialsci.libretexts.org/Bookshelves/Human_Development/Lifespan_Development_(Lumen)/02%3A_Developmental_Theories/2.02%3A_Introduction_to_Psychodynamic_Theories	libretexts	libretexts-0000.json.gz:20391	https://socialsci.libretexts.org/Bookshelves/Human_Development/Lifespan_Development_(Lumen)/02%3A_Developmental_Theories/2.02%3A_Introduction_to_Psychodynamic_Theories
ON1jZP-C2TMxWDgo	An Intersectional Look at Men's Health	1 Cardiovascular Disease Abigail Blanchfield Cardiovascular disease (CVD) refers to a wide range of conditions that are caused by atherosclerosis. Atherosclerosis is when plaque builds up in the walls of arteries, which narrows the arteries and makes it harder for blood to flow back to the heart (American Heart Association, 2017). There are many types of cardiovascular disease, including coronary heart disease, heart failure, and stroke (New York State Department of Health, 2012). CVD is the leading cause of death for all adults in the U.S., and the mortality rate is higher in men than in women. In the U.S., CVD causes 1 in 3 deaths each year, adding up to more than 859,000 people per year, and CVD costs $216 billion in health care system per year (NCCDPHP, 2022). Common risk factors for development of CVD are high blood pressure, high low-density lipoprotein (LDL) cholesterol, diabetes, smoking, obesity, an unhealthy diet, and physical inactivity. High blood pressure, defined as 130/80 mm Hg or higher, contributes to CVD because it damages the inner lining of arteries making them more susceptible to the buildup of plaque, which narrows the arteries that leading to the heart and brain, reducing blood supply. High LDL cholesterol can double a person’s risk of CVD. Excess cholesterol builds up in arterial walls, limiting blood flow to the heart, brain, kidneys, and legs. Diabetes leads to risk factors such as hypertension and increased triglycerides and LDL cholesterol, and adults with diabetes are twice as likely as non-diabetics to have heart disease or a stroke (NCCDPHP, 2022). Obesity can contribute to CVD because it can raise triglyceride and LDL cholesterol levels, while simultaneously lowering HDL cholesterol (“good” cholesterol) levels (Penn Medicine, 2022). “Blood Pressure 365.364” by loonyhiker, Flickr is licensed under CC BY-NC-ND 2.0 This image depicts a man getting his blood pressure checked in a pharmacy. Blood pressure checks are important for health because high blood pressure increases one’s risk of developing CVD. Luckily, many CVD risk factors are preventable; there are many ways to reduce one’s risk of developing CVD. For example, high blood pressure and cholesterol levels can be improved by eating a healthy, low-sodium diet, engaging in regular physical activity, maintaining a healthy weight, and following a recommended medicine regime (NCCDPHP, 2022). Men generally develop CVD earlier in their lifespan than women, by about 10 years, and have a higher risk of coronary heart disease (CHD) than women. CVD is the leading cause of death for men in the United States, accounting for about 1 in every 4 male deaths in 2020 (Centers for Disease Control and Prevention, 2022). Special CVD risks in men include increased stress, low testosterone, and erectile dysfunction. Stress and anger raise both blood pressure and stress hormones, which restricts blood flow to the heart. Additionally, effects of chronic stress and anger can build up over time, which damages arteries and increases risk of developing CVD. Low testosterone is linked to CVD and is considered to be a cardiovascular and metabolic risk factor. This is because the arteries in the penis are much smaller than those in the heart, so arterial damage can be noticed here first, often years before other CVD symptoms present (Johns Hopkins Medicine, 2022). Disparities in Race and Socioeconomic Status Beyond biological sex, race and socioeconomic status (SES) are also associated with disparities in CVD risk and prevalence among men. Socioeconomic status refers to one’s position in society and is derived from a combination of social and economic factors such as income, education, and occupation. Though over the years CVD mortality rates have been on the decline, racial disparities still exist (Ferdinand et al., 2017). Ethnic and racial minority groups have higher rates of CVD and related risk factors because they encounter more barriers to CVD diagnosis, receive lower quality health care, and face poorer health outcomes (Ski et al., 2014). Black men are 2 to 3 times more likely than White men to die from preventable heart disease and stroke (Ferdinand et al., 2017). Hispanic men have increased rates of CVD risk factors, yet lower rates of overall CVD. Increased CVD risk factors include elevated body mass index, with up to 75% of Mexican American men being obese or overweight, and increased prevalence of diabetes and hypertension when compared to non-Hispanic White men (Graham, 2015). Asian American men have a lower likelihood of developing CVD, and a lower likelihood of dying from CVD. In fact, Asian American men are 50 percent less likely to die due to CVD than non-Hispanic white men. This can likely be attributed to lower rates of obesity and hypertension, and cigarette smoking in Asian American men as compared to other male populations (U.S. Department of Health and Human Services Office of Minority Health, 2021). Men who are socioeconomically disadvantaged experience increased rates of CVD. Over the past 50 years, this disparity in CVD rates between low SES and high SES men has widened (Ski et al., 2014). With occupation, a related risk factor for CVD is work stress. Those with high levels of work stress, including job strain and extensive work hours, are at an elevated risk of coronary heart disease and stroke. Work stress increases the risk of many chronic illnesses in addition to CVD, and this link can be seen across race and sex (Kivimaki & Kawachi, 2015). Additionally, those who have higher levels of occupational physical activity are seen to have higher levels of CVD. While physical activity is generally known to benefit cardiovascular health and lower the risk of CVD, increased rates of occupational physical activity, as seen in many blue-collar occupations, is detrimental to cardiovascular health and overall health. Contrastingly, those with increased levels of leisure-time physical activity have lower rates of CVD (Quinn, 2021). The reason for this difference in cardiovascular health outcomes has to do with the type of physical activity performed. Leisure-time physical activity typically involves dynamic movements performed at intense levels. This type of activity improves cardiorespiratory fitness and is usually done voluntarily over short periods of time which allow enough time for recovery in between. In contrast, occupational physical activity often requires static loading, heavy lifting, awkward posture, and other activities that don’t actually improve fitness performed over long periods of time without sufficient recovery time (Holtermann et al., 2018). “Construction workers at project construction site” by World Bank Photo Collection, Flickr is licensed under CC BY-NC-ND 2.0 This image depicts four men working at a construction site. Increased levels of occupational physical activity, like the type of physical activity done at construction sites, is detrimental to cardiovascular health and overall health. In general, those with higher incomes have lower rates of CVD. However, significant changes in one’s income can also affect individuals’ susceptibility to CVD. Considering a 50% increase or decrease in income to be a significant income rise or income drop, it was found that an income drop over 6 years was associated with higher risk of developing CVD, while an income rise over 6 years was associated with lower risk of developing CVD (Wang et al., 2019). Racial disparities in CVD risk factors between Black and White men also still exist across socioeconomic status. Black men had an increased likelihood of having hypertension, diabetes, and obesity when compared to Whites, among those at an income level of $100,000 or higher. These are all significant risk factors for CVD and can lead to poorer health outcomes in Black men. These disparities in CVD risk factors were not seen among those in the lowest SES groups. This data suggests that African American men experience fewer health benefits from increased income level than White men (Bell et al., 2018). There are many factors that may contribute to why these disparities across the intersections of race, occupation, and income may exist. For lower SES groups, poorer CVD outcomes may be attributed to increased exposure to cardiovascular risks such as smoking, excess alcohol consumption, physical inactivity, and poor diet. Additionally, men in low SES groups often have less access to medical care and social support, increased co-morbidity and job stress, and are less likely to engage in health-seeking behaviors than men in higher SES groups (Ski et al., 2014). Call To Action Death rates from CVD have declined over 70% since the 1960s due to improvements in prevention and treatment, but this decline in mortality has begun to flatten. CVD is still the leading cause of death in the United States. The Healthy People Initiative is a national health agenda from the U.S. Department of Health and Human Services that establishes nationwide health improvement priorities and goals for each decade (Pahigiannis et al., 2019). Healthy People 2030 includes goals for preventing and treating CVD and improving overall cardiovascular health, as well as goals for improving men’s health (Heart disease and stroke). Currently there are separate Healthy People goals for CVD and for men, but combining these into male-specific CVD goals would be beneficial in order to create interventions for specific male demographics. Additionally, many research findings that have led to overall improvements in CVD rates have not been effectively translated into clinical practice and public health (U.S. Department of Health and Human Services, 2021). To improve the CVD outcomes, policymakers and practitioners need to implement effective and accessible strategies that help prevent, treat, and control CVD and risk factors. This also includes promoting good cardiovascular health practices from boyhood to manhood to create positive habits that will lead to improved health outcomes. Lifestyle factors contribute greatly to CVD outcomes, and this is where many prevention programs should focus. More importantly, there should also be a focus on accessibility and adaptability of lifestyle improvements. For example, explaining alternatives for recommendations to have a better diet and increased exercise for those who may not have access to healthy grocery stores or safe environments to walk in. There are several countries across the globe where cancer has passed CVD as the leading cause of death, indicating a decrease in CVD (Howard, 2019). This transition is due to improved prevention and treatment practices, and can hopefully be replicated in the U.S. in the near future. Chapter Review Key Takeaways - CVD is the leading cause of death for adults in the U.S., with a higher mortality rate in men than in women. - The most common risk factors for development of CVD are high blood pressure, high LDL cholesterol, diabetes, smoking, obesity, poor diet, and physical inactivity. - Disparities in CVD mortality rate exist across race, occupation, income level, and SES. Chapter Review Questions - Cardiovascular Disease includes which of the following: - A. Coronary Heart Disease - B. Heart failure - C. Stroke - D. All of the above - What is considered high blood pressure? - A. Less than 110/70 - B. Over 120/70 - C. Over 130/80 - D. Over 180/100 - True or False: Erectile dysfunction is an indicator of overall cardiovascular health - A. True - B. False - Do socioeconomically disadvantaged men experience increased or decreased rates of cardiovascular disease compared to socioeconomically advantaged men? - A. Increased - B. Decreased - C. Not enough information given - D. They experience the same rates of CVD as socioeconomically advantaged men References American Heart Association editorial staff. (2017). What is Cardiovascular Disease? American Heart Association. Retrieved October 6, 2022, from https://www.heart.org/en/health-topics/consumer-healthcare/what-is-cardiovascular-disease Baxter, S. L. K., Chung, R., Frerichs, L., Thorpe, R. J., Jr., Skinner, A. C., & Weinberger, M. (2021). Racial Residential Segregation and Race Differences in Ideal Cardiovascular Health among Young Men. Molecular Diversity Preservation International. 10.3390/ijerph18157755 Bell, C. N., Thorpe, R. J., Jr, Bowie, J. V., & LaVeist, T. A. (2018). Race disparities in cardiovascular disease risk factors within socioeconomic status strata. Annals of epidemiology, 28(3), 147–152. https://doi.org/10.1016/j.annepidem.2017.12.007 Centers for Disease Control and Prevention. (2022, October 14). Men and Heart Disease. Centers for Disease Control and Prevention. Retrieved November 3, 2022, from https://www.cdc.gov/heartdisease/men.htm Ferdinand, K. C., Yadav, K., Nasser, S. A., Clayton-Jeter, H. D., Lewin, J., Cryer, D. R., & Senatore, F. F. (2017). Disparities in hypertension and cardiovascular disease in blacks: The critical role of medication adherence.Journal of Clinical Hypertension (Greenwich, Conn.), 19(10), , 1015–1024. https://doi.org/10.1111/jch.13089 Graham G. (2015). Disparities in cardiovascular disease risk in the United States. Current cardiology reviews, 11(3), 238–245. https://doi.org/10.2174/1573403×11666141122220003 Heart Disease and Stroke. (2022). National Center for Chronic Disease Prevention and Health Promotion. Retrieved October 6, 2022, from https://www.cdc.gov/chronicdisease/resources/publications/factsheets/heart-disease-stroke.htm#:~:text=Leading%20risk%20factors%20for%20heart,unhealthy%20diet%2C%20and%20physical%20inactivity Holtermann, A., Krause, N., van der Beek, A.,J., & Straker, L. (2018). The physical activity paradox: six reasons why occupational physical activity (OPA) does not confer the cardiovascular health benefits that leisure time physical activity does. British Journal of Sports Medicine, 52(3), 149. https://doi-org.libproxy.clemson.edu/10.1136/bjsports-2017-097965 Howard, J. (2019, September 3). Cancer now tops heart disease as the no. 1 cause of death in these countries. CNN Health. Retrieved November 4, 2022, from https://www.cnn.com/2019/09/03/health/leading-cause-of-death-cancer-heart-disease-study Kivimäki, M., & Kawachi, I. (2015). Work Stress as a Risk Factor for Cardiovascular Disease. Current cardiology reports, 17(9), 630. https://doi.org/10.1007/s11886-015-0630-8 Pahigiannis, K., Thompson-Paul, A. M., Barfield, W., Ochiai, E., Loustalot, F., Shero, S., & Hong, Y. (2019). Progress toward improved cardiovascular health in the United States. Circulation, 139(16), 1957–1973. https://doi.org/10.1161/circulationaha.118.035408 Ski, C. F., King-Shier, K. M., & Thompson, D. R. (2014). Gender, socioeconomic and ethnic/racial disparities in cardiovascular disease: a time for change. International journal of cardiology, 170(3), 255–257. https://doi.org/10.1016/j.ijcard.2013.10.082 Special Heart Risks for Men. Johns Hopkins Medicine. Retrieved October 7, 2022, from https://www.hopkinsmedicine.org/health/wellness-and-prevention/special-heart-risks-for-men Three Ways Obesity Contributes to Heart Disease . (2019). Penn Medicine. Retrieved October 6, 2022, from https://www.pennmedicine.org/updates/blogs/metabolic-and-bariatric-surgery-blog/2019/march/obesity-and-heart-disease Types of Cardiovascular Disease. (2012). New York State Department of Health. Retrieved October 6, 2022, from https://www.health.ny.gov/diseases/cardiovascular/heart_disease/types_of_cv.htm Quinn, T. D., Yorio, P. L., Smith, P. M., Seo, Y., Whitfield, G. P., & Barone Gibbs, B. (2021). Occupational physical activity and cardiovascular disease in the United States. Occupational and environmental medicine, 78(10), 724–730. https://doi.org/10.1136/oemed-2020-106948 U.S. Department of Health and Human Services Office of Minority Health. (2021, November 2). Office of Minority Health. Heart Disease and Asian Americans – The Office of Minority Health. Retrieved November 3, 2022, from https://minorityhealth.hhs.gov/omh/browse.aspx?lvl=4&lvlid=49 U.S. Department of Health and Human Services. (2021, February 3). Cardiovascular disease is on the rise, but we know how to curb it. we’ve done it before. National Heart Lung and Blood Institute. Retrieved November 4, 2022, from https://www.nhlbi.nih.gov/news/2021/cardiovascular-disease-rise-we-know-how-curb-it-weve-done-it U.S. Department of Health and Human Services. (n.d.). Heart disease and stroke. Heart Disease and Stroke – Healthy People 2030. Retrieved November 4, 2022, from https://health.gov/healthypeople/objectives-and-data/browse-objectives/heart-disease-and-stroke Wang, S. Y., Tan, A., Claggett, B., Chandra, A., Khatana, S., Lutsey, P. L., Kucharska-Newton, A., Koton, S., Solomon, S. D., & Kawachi, I. (2019). Longitudinal Associations Between Income Changes and Incident Cardiovascular Disease: The Atherosclerosis Risk in Communities Study. JAMA cardiology, 4(12), 1203–1212. https://doi.org/10.1001/jamacardio.2019.3788	3,182	common-pile/pressbooks_filtered	https://opentextbooks.clemson.edu/hlth3200baxter/chapter/cardiovascular-disease-in-men-at-the-intersections-of-race-and-occupation-income/	pressbooks	pressbooks-0000.json.gz:35082	https://opentextbooks.clemson.edu/hlth3200baxter/chapter/cardiovascular-disease-in-men-at-the-intersections-of-race-and-occupation-income/
_JlL2XZWhX80KU6K	OER by Subject Directory	45 Audio Bach’s Open Goldberg Variations played by Kimiko Ishizaka (CC0). The Open Goldberg Variations (Johann Sebastian Bach, BWV 988), played by Kimiko Ishizaka on a Bösendorfer 290 Imperial piano, are free to download and share. Courses Art and Music Since 1945 by Ohio State University (CC BY). This open website is used for a course on Art and Music since 1945 offered at The Ohio State University. The website contains a collection of biographies of artists and musicians, a sample syllabus, and assignments. Its companion textbook is meant to be A Quick and Dirty Guide to Art, Music, and Culture, which is posted below. Textbooks Brass Techniques and Pedagogy by Brian Weidner (CC BY-NC-SA). Textbook for undergraduate brass methods course focusing on brass instrument techniques and pedagogy. Comprehensive Musicianship, A Practical Resource by Randall Harlow; Heather Peyton; Jonathan Schwabe; and Daniel Swilley (CC BY-NC-SA). (Also see Aural Training and Sight Singing Supplement for Comprehensive Musicianship, A Practical Resource) This book presents an integrated suite of learning resources developed for the core music theory and musicianship curriculum at the University of Northern Iowa School of Music. It provides a more comprehensive symbiosis of musicianship and music theory learning than can be found in existing textbooks, including engaging and progressive video demonstrations and interactive listening and vocal exercises that integrate musical knowledge with foundational musical skills. Fundamentals, Function, and Form by Andre Mount (CC BY-NC). This text provides readers with a comprehensive study of the theory and analysis of tonal Western art music. Author Andre Mount begins by building a strong foundation in the understanding of rhythm, meter, and pitch as well as the notational conventions associated with each. From there, he guides the reader through an exploration of polyphony—the simultaneous sounding of multiple independent melodies—and an increasingly rich array of different sonorites that grow out of this practice. The book culminates with a discussion of musical form, engaging with artistic works in their entirety by considering the interaction of harmonic and thematic elements, but also such other musical dimensions as rhythm, meter, texture, and expression. Multimodal Musicianship by Victoria Malawey (CC-BY-NC-SA) This book teaches learning music theory and ear training. The content engages concepts related to tonal harmony, suitable for a two- or three-semester music theory and ear training curriculum in a liberal arts college or other higher education setting. This collection of materials offers multiple modes of engaging content—with text, musical examples, audio examples, video content, application activities, and links to supplemental content—designed for users to learn and reinforce their knowledge according to their learning styles and needs. Music and the Child (CC-BY-NC-SA). Children are inherently musical. As professional instructors, childcare workers, or students looking forward to a career working with children, we should continuously search for ways to tap into children’s natural reservoir of enthusiasm for singing, moving and experimenting with instruments. This book explores a holistic, artistic, and integrated approach to understanding the developmental connections between music and children. Music Appreciation (CC BY-NC-ND). For the course that this text accompanies the goals for each student are: To gain basic exposure to the elements of music and their treatment in music, to learn historical and cultural signifiers in a diverse body of music, to approach listening to music actively/analytically and to reflect on the experience, to understand the factors that contribute to musical style in their own music and music presented in the course, to gain knowledge about differing musical aesthetics and trends, and to become more knowledgeable and sensitive to varied human expression through music. Music Appreciation: History, Culture, and Context (CC BY). Music makes us human. Every culture on earth has music. In fact, every human society extending back into prehistoric times has had music. Most of us are surrounded by music. We use it to enhance our mood and to regulate our metabolism, to keep us awake and help us go to sleep, as background to accompany the work, study, exercise, and relaxation that fills our days. This textbook is about the musical imagination. It’s how to think about music, but it’s also about music as a mode of thinking. Music Theory for the 21st-Century Classroom (GNU Free Documentation License). This is an openly–licensed online four–semester college music theory textbook. It differs from other music theory textbooks by focusing less on four–part (SATB) voiceleading and more on relating harmony to the phrase. Also, in traditional music theory textbooks, there is little emphasis on motivic analysis and analysis of melodic units smaller than the phrase. Open Music Theory: Version 2 (CC BY-SA). This is an open-source, interactive, online “text”book for college-level music theory courses. Original Etudes for the Developing Conductor by Caldwell, Jonathan, Shapiro, Derek (CC BY-NC-SA) This book is a collection of supplemental études designed to enhance contemporary conducting pedagogy by amplifying the voices of composers from historically excluded groups. Each étude was commissioned from and composed by a living composer, the majority of whom are woman-identifying composers and/or composers of color. Each étude also addresses multiple specific pedagogical goals common to all conducting classrooms. A Quick and Dirty Guide to Art, Music, and Culture (CC BY). SITE NOT AVAILABLE 2/24/25 An open textbook by The Ohio State University that discusses art and music in the context of popular culture. It is meant to work with the open course Art and Music Since 1945, which is posted above. Resonances: Engaging Music in Its Cultural Context by Esther Morgan-Ellis (CC BY-SA). Although this book is intended primarily for use in the college music appreciation classroom, it was designed with consideration for independent learners, advanced high school students, and experienced musicians. That is to say, it includes enough detail that expert guidance is not required and is written using broadly-accessible language. At the same time, it addresses advanced topics and positions music as a serious object of study. Sight-Reading for Guitar: The Keep-Going Method Book and Video Series by Chelsea Green (CC BY). This book teaches guitar players from all musical backgrounds to understand, read, and play modern staff notation in real time. The Keep-Going Method is designed to impart the knowledge, skills and attitudes needed for sight-reading with efficiency, fun and encouragement. Soul Music Odyssey USA 1968 – 2nd ed by Jonas Bernholm (CC BY-NC-SA). This is from the author’s research trip 1968 (plus a little from 1978). The first version was basically a translation of articles written in Swedish and originally published in the Swedish magazine Jefferson (world’s oldest blues magazine) plus a summary. It was published online by York University Libraries in 2017. This edition includes illustrations and corrections. Understanding Music: Past and Present by N. Alan Clark, Thomas Heflin, Jeffrey Kluball and Elizabeth Kramer (CC BY-SA). Understanding Music: Past and Present is an open Music Appreciation textbook co-authored by music faculty across Georgia. The text covers the fundamentals of music and the physics of sound, an exploration of music from the Middle Ages to the present day, and a final chapter on popular music in the United States. Unlocking the Digital Age: The Musician’s Guide to Research, Copyright, and Publishing by Kathleen DeLaurenti and Andrea I. Copland (CC BY). Based on coursework developed at the Peabody Conservatory, this book serves as a crucial resource for early career musicians navigating the complexities of the digital era. This guide bridges the gap between creative practice and scholarly research, empowering musicians to confidently share and protect their work as they expand their performing lives beyond the concert stage as citizen artists. It offers a plain language resource that helps early career musicians see where creative practice and creative research intersect and how to traverse information systems to share their work. As professional musicians and researchers, the authors’ experiences on stage and in academia makes this guide an indispensable tool for musicians aiming to thrive in the digital landscape. Pressbooks book of the month for March, 2024. Videos Acoustics by Professor Glive at University of Edinbourgh (CC BY). A set of four videos on acoustics.	1,726	common-pile/pressbooks_filtered	https://pressbooks.saskpolytech.ca/oerdiscipline/chapter/music/	pressbooks	pressbooks-0000.json.gz:51705	https://pressbooks.saskpolytech.ca/oerdiscipline/chapter/music/
N_s0jOZ1fvg8Vn1D	Gender in Canada: A Companion Workbook	4 Social Constructions Pooja Mohabeer Social constructionism is the idea that society is not given in the order of nature, but rather something that we make. But how can we discern if something in our society is socially constructed? Two questions need to be asked: Can it be historically traced? And, does its meaning differ cross-culturally? In exploring their role in society, we can argue that “sex,” “gender,” and “sexuality” are socially constructed. Throughout history, in different parts of the world and in different cultures, societies have had different and distinct systems of sex, gender, and sexuality rooted in how that society functions. Dualism is foundational to dominant gender ideology. Societies’ gravitation towards dualisms is problematic because dualism’s very nature renders one part superior over the other. For instance, patriarchy allows men to experience life more conveniently than women. This is exemplified in the diminishment of women’s rights, the gender pay gap, the underrepresentation of women in positions of power, the overrepresentation of women among the impoverished, and more. Members of the LGBTQA+ community, or anyone who does not conform to the dominant gender ideology, face violence and discrimination. One’s access to basic life necessities, work, healthcare, and education can be adversely affected, and one’s power and influence become limited. But anything socially constructed can be reconstructed. This insight emphasizes that we can help reform and improve societal beliefs, values, and practices to be more inclusive of the many ways to be sexed and gendered. Social Construction: anything viewed to have an inherent or natural conception, but is actually established and maintained by social interests Dualism: an ideology that sees various aspects of reality as divided into two parts or options anything viewed to have an inherent or natural conception, but is actually established and maintained by social interests an ideology that sees various aspects of reality as divided into two parts or options	408	common-pile/pressbooks_filtered	https://kpu.pressbooks.pub/genderincanadaworkbook/chapter/chapter-3/	pressbooks	pressbooks-0000.json.gz:6776	https://kpu.pressbooks.pub/genderincanadaworkbook/chapter/chapter-3/
1u-XGrYZCYcfFeiG	3.3: Linear Congruences	3.3: Linear Congruences Because congruences are analogous to equations, it is natural to ask about solutions of linear equations. In this section, we will be discussing linear congruences of one variable and their solutions. We start by defining linear congruences. A congruence of the form $ax\equiv b(mod\ m)$ where $x$ is an unknown integer is called a linear congruence in one variable. It is important to know that if $x_0$ is a solution for a linear congruence, then all integers $x_i$ such that $x_i\equiv x_0 (mod \ m)$ are solutions of the linear congruence. Notice also that $ax\equiv b (mod\ m)$ is equivalent to a linear Diophantine equation i.e. there exists $y$ such that $ax-my=b$. We now prove theorems about the solutions of linear congruences. Let $a,b$ and $m$ be integers such that $m>0$ and let $c=(a,m)$. If $c$ does not divide $b$, then the congruence $ax\equiv b(mod \ m)$ has no solutions. If $c\mid b$, then \[ax\equiv b(mod \ m)\] has exactly $c$ incongruent solutions modulo $m$. As we mentioned earlier, $ax\equiv b(mod \ m)$ is equivalent to $ax-my=b$. By Theorem 19 on Diophantine equations, we know that if $c$ does not divide $b$, then the equation, $ax-my=b$ has no solutions. Notice also that if $c\mid b$, then there are infinitely many solutions whose variable $x$ is given by \[x=x_0+(m/c)t\] Thus the above values of $x$ are solutions of the congruence $ax\equiv b(mod \ m)$. Now we have to determine the number of incongruent solutions that we have. Suppose that two solutions are congruent, i.e. \[x_0+(m/c)t_1\equiv x_0+(m/c)t_2(mod \ m).\] Thus we get \[(m/c)t_1\equiv (m/c)t_2(mod \ m).\] Now notice that $(m,m/c)=m/c$ and thus \[t_1\equiv t_2(mod \ c).\] Thus we get a set of incongruent solutions given by $x=x_0+(m/c)t$, where $t$ is taken modulo $c$. Notice that if $c=(a,m)=1$, then there is a unique solution modulo m for the equation $ax\equiv b(mod \ m)$. Let us find all the solutions of the congruence $3x\equiv 12 (mod \ 6)$. Notice that $(3,6)=3$ and $3\mid 12$. Thus there are three incongruent solutions modulo $6$. We use the Euclidean algorithm to find the solution of the equation $3x-6y=12$ as described in chapter 2. As a result, we get $x_0=6$. Thus the three incongruent solutions are given by $x_1=6(mod \ 6)$, $x_1=6+2=2(mod \ 6)$ and $x_2=6+4=4(mod \ 6)$. As we mentioned earlier in Remark 2, the congruence $ax\equiv b(mod \ m)$ has a unique solution if $(a,m)=1$. This will allow us to talk about modular inverses. A solution for the congruence $ax\equiv 1 (mod\ m)$ for $(a,m)=1$ is called the modular inverse of $a$ modulo m. We denote such a solution by $\bar{a}$. The modular inverse of 7 modulo 48 is 7. Notice that a solution for $7x\equiv 1(mod \ 48)$ is $x\equiv 7 (mod \ 48)$. Exercises - Find all solutions of $3x\equiv 6(mod \ 9)$ . - Find all solutions of $3x\equiv 2(mod \ 7)$ . - Find an inverse modulo 13 of 2 and of 11. - Show that if $\bar{a}$ is the inverse of $a$ modulo $m$ and $\bar{b}$ is the inverse of $b$ modulo $m$, then $\bar{a}\bar{b}$ is the inverse of $ab$ modulo $m$. Contributors and Attributions - Dr. Wissam Raji, Ph.D., of the American University in Beirut. His work was selected by the Saylor Foundation’s Open Textbook Challenge for public release under a Creative Commons Attribution ( CC BY ) license.	730	common-pile/libretexts_filtered	https://math.libretexts.org/Bookshelves/Combinatorics_and_Discrete_Mathematics/Elementary_Number_Theory_(Raji)/03%3A_Congruences/3.03%3A_Linear_Congruences	libretexts	libretexts-0000.json.gz:27469	https://math.libretexts.org/Bookshelves/Combinatorics_and_Discrete_Mathematics/Elementary_Number_Theory_(Raji)/03%3A_Congruences/3.03%3A_Linear_Congruences
gUr9D6KuNiHKQibs	Gender in Canada: A Companion Workbook	19 Sex Work Rebecca Yoshizawa If feminism supports people’s right to bodily autonomy, including the choice of whether to have sex or not, it must be the case that sex work is of central concern to feminism. Feminism typically also supports the right to work, regardless of sex or gender. It seems to follow, then, that feminism would support the idea that “sex work is work,” and that supporting sex workers’ right to do their work safely would be a clear feminist point of advocacy. However, sex work, and its relationship to feminism, is complex. Some feminists argue that sex work is inherently misogynistic and can never reflect women’s autonomy, empowerment, self-determination, or independence. They variously argue that women only turn to sex work due to vulnerabilities that are structured in patriarchy, that sex work is degrading, that paying for sex is exploitation; feminists may also address sex work as immoral. For the latter argument, feminists can find abundant support in religious, state, and other cultural understandings of family and sex, where sex outside monogamy is typically considered to be deviant. The worker and/or the client may therefore be variously penalized. There are several issues with this form of sex-worker-exclusionary feminism. One is the assumption that only cisgender women do sex work. Sex work is not only a women’s issue, and not only circumscribed by patriarchy. Men, non-binary, and trans people also do sex work. Another issue is the assumption that criminalization deters sex work and clients from exchanges. The assumption suggests that criminalizing sex work protects women and those vulnerable to the sex trade and human trafficking. However, other feminists argue that criminalization is in fact an ironic cause of the dangers of sex work. Because sex work is criminalized, there are no occupational health and safety protections. Negotiations and services are rushed and secretive. There are few safe spaces to do sex work. Sex workers are made vulnerable socially and structurally in this way, and those vulnerabilities can be compounded with the structural violences of racialization, colonialism, and poverty. Another issue is that sex workers can report enjoying their work and finding fulfilment in it. They can be described as sex positive, and critique the slut-shaming that comes with negative understandings of sex work. Where the term “prostitute” is dehumanizing and carries derogatory historical and cultural denotations, “sex work” suggests that sex can be a normalized and legitimate service provided by workers in a society.	529	common-pile/pressbooks_filtered	https://kpu.pressbooks.pub/genderincanadaworkbook/chapter/sex-work/	pressbooks	pressbooks-0000.json.gz:6793	https://kpu.pressbooks.pub/genderincanadaworkbook/chapter/sex-work/
w8Yzv3I0duhL5W9u	Canadian History: Pre-Confederation	10.3 Immigration From 1783 until 1812 the most important source of immigrants to British North America was the United States. Movement across the border was easy and the host community was, outside of Lower Canada, overwhelmingly and increasingly North American in its accents and values. That ended with the War of 1812. After 1815 British North America became much more British than it had ever been before. Emigration from the British Isles was the single greatest source of settlers in the Atlantic colonies, a fact that distinguishes their society from that of the Canadas in these years. Scottish settlers under the guidance of Lord Selkirk descended upon Prince Edward Island to take up farms in the early days of the century, and they were followed in the years to come by many others. Mostly these were Highland Scots, removed from their ancestral farmlands by the process known as the “clearances.” They were followed by Irish immigrants who came to represent a significant share of colonial population by 1850. Irish Immigrants Ireland produced the largest waves of emigration of any European country during the 19th century. This phenomenon is often associated exclusively with the Famine Irish, the millions of refugees from the potato famine that wracked their homeland in the late 1840s. Irish migration to British North America, however, began in earnest much earlier. In the dying days of the Napoleonic Wars, Irish immigrants began arriving in east coast ports in large numbers. The towns of Newcastle, Chatham, and Miramichi saw hundreds arrive before 1820. Not all were Catholics but almost all were economically on the margin. Sectarian hostility between the Irish Protestants and Catholics who arrived around the same time soon spread to the larger host population. Further Irish immigration tended to be badly timed, and the reception of the host communities was predictably muted at best, hostile at worst. The post-Napoleonic War years witnessed economic downturns in many parts of the British Isles, including Ireland. In the 1820s, as the farming frontier was growing in Upper Canada and in Lower Canada’s Eastern Townships, Irish immigrants arrived. Some of these had enough money to make a go of it. They were followed in the 1830s, however, by less prosperous countrymen and women who were fleeing more severe hardship at home. Overwhelmingly Catholic, they arrived in large numbers in the St. Lawrence, and the mortality among passengers was severe. In June 1832, Irish immigrants brought with them a hidden passenger onboard the Carrick: cholera. Having killed tens of thousands in Britain, the disease came ashore at Quebec City and spread rapidly to Montreal and then Upper Canada. More than 9,000 Canadians — Upper and Lower — died, the largest concentration being in Montreal. Cholera is associated with human waste, and at the time, sewers in the towns were very poorly developed; it was common practice to dump buckets of sewage into the streets where it mixed with an abundant supply of horse manure. The Irish — poor and almost immediately shunned by the locals — found themselves in shantytowns with even worse drainage or in quarantine facilities (specifically on Grosse Isle) where sanitation was appalling. As a result, the Irish immigrants themselves died in huge numbers. (This was a near-global epidemic, one that originated in India and by 1835 had made landfall on the northwest coast. There, cholera joined measles, mumps, and other exotic diseases that easily claimed 25% to 35% of the Aboriginal communities they infected.)[1] Another consequence of the cholera epidemic was social and political turmoil, which was especially acute in Lower Canada where fear of a British plot to eradicate the Catholic Canadien population survived from generation to generation. Were the Irish merely instruments of British contempt for the Canadiens? Many thought so at the time. The Irish were, therefore, ostracized and discriminated against while the clergy and other spokesmen for the Canadiens whipped up feeling against the British generally. The cholera epidemic was, then, one factor among several in the 1830s that led to growing support for a rebellion. Irish immigration in the 1840s must be placed in this context. Fear of cholera and diseased immigrants was a reality. As well, the Irish Canadians had moved into fields of work such as canal construction, which were generally regarded dimly by most English and French Canadians, and this increased the anti-Irish sentiment. The independent farmer was the antithesis of the low-wage-earning, work-camp-dwelling proletarian. “Townies” viewed the Irish navvies as rough and uncivilized and a danger to their safety. Worse still, the land boom in Upper Canada that had sustained the economy alongside the wheat boom was in a trough in the late 1840s. Immigration had been much sought after when there was a lot of land available and when it fetched a good price; when the Famine Irish arrived they were too poor to buy land, the market was depressed anyway, and no one was enthusiastic about more competition. Things, of course, were much worse for the Irish themselves. Those who were quarantined on Grosse Isle and on Partridge Island in the Bay of Fundy in 1847 had to further contend with an outbreak of typhus. Thousands died. Even in Upper Canada voices could be heard criticizing the British government for shovelling out its poor into British North America. Immigration from Ireland transformed Toronto from an essentially anglophone and Protestant city to one of pluralities: by 1860 there were comparable numbers of Catholics and Anglicans, followed by smaller numbers of Presbyterians, Methodists, and still smaller denominations.[2] Almost all of these Catholics were Irish. Their presence gave purpose to the Orange Order, whose lodges stood as expressions of Protestant authority and xenophobic reaction to the immigrant masses. This arose, in large part, because the Irish tended to settle in urban areas, though not necessarily in tight ethnic enclaves. In Montreal they dominated St. Anne’s Ward, but in Toronto they were spread throughout the east and west ends, wherever affordable housing could be found.[3] Key Points - The British Isles contributed the largest number of immigrants to British North America between 1818 and 1867, the Irish constituting a major share. - Many of the 19th century immigrants were refugees from landlessness, and poverty, and/or famine. - Conditions for immigrants were typically poor and worsened by the presence of epidemic diseases. - The Irish, Scots, Welsh, and English immigrants of these years contributed to the diversification of cultural institutions as well as sectarian hostilities. Attributions Figure 10.2 British Immigration to BNA, 1815-1860, by John Belshaw is used under a CC-BY 4.0 license. Figure 10.3 View of Montreal 1852 by Skeezix1000 is in the public domain. Long Descriptions \| Year \| Emmigration, UK to BNA Ports \| Immigrant arrivals at Quebec \| \|---\|---\|---\| \| 1815 \| 0 \| \| \| 1817 \| 10,000 \| \| \| 1819 \| 22,000 \| \| \| 1821 \| 10,000 \| \| \| 1823 \| 11,000 \| \| \| 1825 \| 10,000 \| \| \| 1827 \| 16,000 \| \| \| 1829 \| 17,000 \| 18,000 \| \| 1831 \| 40,000 \| 40,000 \| \| 1833 \| 45,000 \| 45,000 \| \| 1835 \| 16,000 \| 16,000 \| \| 1837 \| 30,000 \| 21,000 \| \| 1839 \| 2,000 \| 2,000 \| \| 1841 \| 39,000 \| 24,000 \| \| 1843 \| 21,000 \| 20,000 \| \| 1845 \| 30,000 \| 21,000 \| \| 1847 \| 110,000 \| 90,000 \| \| 1849 \| 23,000 \| 23,000 \| \| 1851 \| 26,000 \| 26,000 \| \| 1853 \| 32,000 \| 37,000 \| \| 1855 \| 57,000 \| 42,000 \| \| 1857 \| 21,000 \| 18,000 \| \| 1859 \| 7,000 \| 7,000 \| - Geoffrey Bilson, A Darkened House: Cholera in Nineteenth Century Canada (Toronto: University of Toronto Press, 1980). ↵ - Peter G. Goheen, "Currents of Change in a Canadian City, 1850-1900," in The Canadian City: Essays in Urban and Social History, eds. Gilbert A. Stelter and Alan F. J. Artibise (Ottawa: Carleton University Press, 1984), 93-4. ↵ - John Zucchi, A History of Ethnic Enclaves in Canada (Ottawa: Canadian Historical Association Booklet no.31, 2007), 3. ↵	1,755	common-pile/pressbooks_filtered	https://ecampusontario.pressbooks.pub/preconfedcdnhist/chapter/10-3-immigration/	pressbooks	pressbooks-0000.json.gz:39733	https://ecampusontario.pressbooks.pub/preconfedcdnhist/chapter/10-3-immigration/
HGY0ALin4JCbe0r6	4.7: Chapter Review - Key Terms	Skip to main content 4.7: Chapter Review - Key Terms - - Last updated - - Save as PDF - Key Terms - Automatic substitution - feature in Docs that allows the user to type a word and have it automatically replaced with a predetermined symbol or special character - bookmark - tool that lets the user connect different parts of the document using links - checklist - type of bulleted list that adds a checkbox to the beginning of each line - drop cap - when the first letter of the first sentence in a paragraph is in a large, stylized font - endnote - note or citation at the end of the document - footer - bottom part of the page within the bottom margin, which you can see and configure in Print Layout viewing mode - footnote - note or citation at the bottom of the page - Format Painter - tool in Word that lets you copy the formatting of one area of a document to another area of the same or other file - formatting marks - symbols Word uses to tell the user where a space, line, or the like are in the document; these are usually hidden unless the user chooses to see them - header - top part of the page within the top margin, which you can see and configure in Print Layout viewing mode - hierarchy chart - type of chart that visualizes the chain of command or supervision at an organization - multilevel list - type of list that has hierarchical levels with different bullet styles for each level - page numbering - ability of Word to number your pages in documents; they can be in the header or in the footer - Paragraph Styles - Google formatting tool similar to Word’s Styles; used to create headings and apply document-wide formatting so that you can generate a table of contents (and document outline) - process chart - way to represent a multistep process in a document; it shows the steps in the process, the order in which to do them, and the dependencies for an outcome - reference - method of giving credit to the texts and other sources you used to furnish your document with information or data - SmartArt - tool in Word that lets you design organizational charts or flowcharts - symbol - special character not found on the keyboard such as currency symbols or Greek letters - table of figures - list of graphs, tables, or images that are in the document - title page - cover page of a document - Trust Center - part of Word’s configurable options, which lets you personalize your privacy settings - WordArt - tool in Word that lets you create artistic text	603	common-pile/libretexts_filtered	https://workforce.libretexts.org/Bookshelves/Information_Technology/Computer_Applications/Workplace_Software_and_Skills_(OpenStax)/04%3A_Document_Preparation/4.07%3A_Chapter_Review_-_Key_Terms	libretexts	libretexts-0000.json.gz:2320	https://workforce.libretexts.org/Bookshelves/Information_Technology/Computer_Applications/Workplace_Software_and_Skills_(OpenStax)/04%3A_Document_Preparation/4.07%3A_Chapter_Review_-_Key_Terms
SYjejqyYXT5I777n	LIBRARY is the new PUBLISHER	The Effects of Government Funding Public funding and government support is beneficial for OER programs. However, this presents a problem for programs’ solvency and sustainability. Because governments change over time, funding cannot be guaranteed even year to year. Even programs like SUNY that are currently well-funded by state grants are actively planning ahead for ways to create a sustainable business model and decrease their dependency on unreliable funding. Incentivizing Authorship While in most cases getting faculty to believe in and support the OER movement is just a matter of education and advocacy, getting faculty to create open educational resources is a more complex issue. Not all institutions have the infrastructure in place to give faculty enough incentive to take on a project. One such incentive is course releases. Institutions like UTA do not yet have clear processes in place to allow faculty to dedicate their time to OER production. At Seneca, only a small number of faculty can qualify. Another incentive is recognition of a publication for inclusion in review and tenure packets. Though the process may differ from program to program, open educational resources are not guaranteed to count toward a faculty author’s tenure application. This can discourage faculty from wanting to sacrifice the substantial amount of time it takes to author a text. A Search for Sustainability Many of the OER efforts described in this study are nascent. In current stages, these schools’ thoughts are first and foremost focused on building workflows that are financially sustainable and can be grown over time. In some cases, this involves increasing advocacy and building relationships with faculty or other departments on campus. In other cases, the demand for OER may soon exceed what the program is capable of providing, and there’s a need to either grow the program or establish what maximum capacity looks like. Institutions are experimenting with business models that they hope will allow them to build lasting OER programs that aren’t dependent on unreliable third-party grants or government funding and will allow them to meet the needs for open resources at their institution.	448	common-pile/pressbooks_filtered	https://pressbooks.pub/libraryisthenewpublisher/chapter/barriers-to-success/	pressbooks	pressbooks-0000.json.gz:11594	https://pressbooks.pub/libraryisthenewpublisher/chapter/barriers-to-success/
A48qoPlEmrKhCtlU	Humans R Social Media - 2024 "Living Book" Edition	Thank you to the students who openly licensed the work included in our collections We are grateful to the following student contributors for making the inclusion of student work in this book possible.	42	common-pile/pressbooks_filtered	https://opentextbooks.library.arizona.edu/humansrsocialmedia/chapter/thank-you-to-the-students-who-contributed-to-our-collections/	pressbooks	pressbooks-0000.json.gz:45169	https://opentextbooks.library.arizona.edu/humansrsocialmedia/chapter/thank-you-to-the-students-who-contributed-to-our-collections/
BGpkUsanYmJuU7I5	Foundations in Sociology I	10 Module 10: Non-Conformity and Social Control: Health and Medicine Learning Objectives - Describe the relationship between the body and society. - Elaborate the meaning of the concept biopolitics as a relationship between the body and modern forms of power. - Distinguish between moral and statistical meanings of norm. - Discuss how medical sociology describes illness and health as social and cultural constructions. - Define the field of social epidemiology and discuss how social epidemiology can be applied to the distribution of health outcomes in Canada and elsewhere. - Describe how health issues and health disparities are related to social class, gender, race and ethnicity, generation and the global distribution of wealth. - Give an overview of mental health and disability issues in Canada. - Explain the terms stigma and medicalization. - Apply functionalist, critical, and interpretive sociological perspectives to social issues of health and illness. 10.0 Introduction to Health and Medicine In 2012, a pertussis (whooping cough) outbreak in B.C., Alberta, Ontario, and New Brunswick sickened 2,000 people and resulted in an infant death in Lethbridge. In the United States, where there were 18,000 cases and nine deaths, it was the worst outbreak in 65 years (Picard, 2012). Researchers, suspecting that the primary cause of the outbreak was the waning strength of pertussis vaccines in older children, recommended a booster vaccination for 11–12-year-olds and pregnant women (Zacharyczuk, 2011). Pertussis is most serious for babies; one in five must be hospitalized, and since they are too young for the vaccine themselves, it is crucial that people around them be immunized (Centers for Disease Control 2011). In response to the outbreak, health authorities in various parts of Canada offered free vaccination clinics for parents with infants under one. Typically Canadian children are vaccinated for whooping cough, diphtheria, and tetanus (a combined vaccine known as DTaP) at ages 2, 4, 6, and 18 months, and then again at ages 4 to 6 years and 14 to 16 years (Picard, 2012). But what of people who do not want their children to have this vaccine, or any other? That question is at the heart of a debate that has been simmering for years. Vaccines are biological preparations that improve immunity against a certain disease. Vaccines have contributed to the eradication and weakening of numerous infectious diseases in human populations, including smallpox, polio, mumps, chicken pox, and meningitis. However, many people express concern about potential negative side effects from vaccines. These concerns range from fears about overloading the child’s immune system to controversial reports about devastating side effects of the vaccines. One misapprehension is that the vaccine itself might cause the disease it is supposed to be immunizing. Another commonly circulated concern is that vaccinations, specifically the MMR vaccine (MMR stands for measles, mumps, and rubella), are linked to autism. The autism connection has been particularly controversial. In 1998, two British physicians, Andrew Wakefield and John Walker-Smith, published a study in Great Britain’s Lancet magazine that linked the MMR vaccine to bowel disease and autism. The report received a lot of media attention, resulting in British immunization rates decreasing from 91 percent in 1997 to almost 80 percent by 2003, accompanied by a subsequent rise in measles cases (Devlin, 2008). A prolonged investigation by the British Medical Journal proved that not only was the link in the study nonexistent, but that Dr. Wakefield had falsified data in order to support his claims (CNN, 2011). Both Dr. Wakefield and Dr. Walker-Smith were discredited and stripped of their licenses, but the doubt still lingers in many parents’ minds. A subsequent ruling in 2012 by the British High Court stated that the British General Medical Council’s charges of misconduct against the two physicians were without basis and that they had never claimed that vaccines caused autism (Aston 2012). In Canada, many parents still believe in the now-discredited MMR-autism link and refuse to vaccinate their children. Autism is a complex condition of unclear origin, yet the symptoms of its onset occur roughly at the same time as MMR vaccinations. In the absence of clear biomedical explanations for the condition, parents draw their own conclusions or seek alternative explanations. They feel forced to make a risk assessment between the dangers of measles, mumps and rubella on one side and autism on the other. Other parents choose not to vaccinate for various reasons like religious or health beliefs. In the United States, a boy whose parents opted not to vaccinate returned home after a trip abroad; no one yet knew he was infected with measles. The boy exposed 839 people to the disease and caused 11 additional cases of measles, all in other unvaccinated children, including one infant who had to be hospitalized. According to a study published in Pediatrics, the outbreak cost the public sector $10,376 per diagnosed case. The study further showed that the intentional non-vaccination of those infected occurred in students from private schools, public charter schools, and public schools in upper-socioeconomic areas (Sugerman et al., 2010). Should parents be forced to immunize their children? What might sociologists make of the fact that most of the families who chose not to vaccinate were of a higher socioeconomic group? How does this story of vaccines in a high-income region compare to that in a low-income region, like sub-Saharan Africa, where populations are often eagerly seeking vaccines rather than refusing them? 10.1 The Sociology of the Body and Health Whereas human bodies have not changed radically since the evolution of Homo sapiens sapiens 200,000 years ago, our relationship to our bodies has. Due to the change in the relationship to our bodies over the last 150 years — in the forms of bio-medical knowledge, nutrition, hygiene, and sanitation, etc. — on average, we are healthier, taller, and live longer than our ancestors lived. In turn, these changes have had direct consequences for social organization. For example, the phenomenon of the aging population has obliged governments, institutions, and individuals to rethink everything from pension plans, health care provisions, and mandatory retirement ages, to the bias towards youth in popular culture and marketing. As a political constituency, seniors are both significant in numbers and more engaged than young people are. They also are healthier and live longer on average than previous generations of seniors. They are therefore in a position to press government to shift resources away from young people’s concerns to meet their own interests: for example, away from funding education to investing in medical research. In his science fiction novel Holy Fire (1996), Bruce Sterling extrapolates from this phenomenon to imagine a future gerontocracy where seniors hold all the wealth and power, as well as the resources to invest in radical medical procedures, which extend their lives and health indefinitely. Young people are excluded from meaningful participation in society, and their youth culture is no longer celebrated but seen as reckless and irresponsible. The primary virtue of the gerontocrats is their continued health, so their lifestyle involves a strict regimen of exercise, diet, avoidance of intoxicants, and aversion to risk. Sterling raises the question of a future epoch of post-humanity, i.e., a period in which the mortality that defined the human condition for millennia has effectively been eliminated through the technologies of life preservation. Is this our future? How malleable is the human body? To what degree can it be redesigned to suit our purposes? In what way is the human body a sociological phenomenon as well as a physiological phenomenon? 10.1.1 The Sociology of the Body Michel Foucault has argued that the shift in the way we related to our bodies in the 18th and 19th centuries is central to the formation of modern institutions and societies. In monastic practices, military discipline, factory organization, hospital design, prison rehabilitation, and educational programs, the individual body was redefined as something that needed to be trained, disciplined, and transformed. For the first time in history, the body became the center of numerous detailed procedures designed to improve its performance in a variety of institutional contexts. At the same time, the qualities of the life of the population as a whole came to be seen as a concern for government: public health, sanitary conditions in cities, the rate of population increase, the need for a productive workforce, etc. Foucault calls this the era of biopolitics: “the entry of life into history” or the moment when “the administration of bodies and the calculated management of life” became the priority in the organization of social life (Foucault, 1980). Authorities and individuals themselves began to seek ways in which to foster life and improve the body’s capacity for efficiency, health, learning, skill, and responsiveness. Today, preserving and fostering life might be the one central unifying value that underlies all of our politics and all of our social policy concerns. Foucault cites a military ordinance of 1764 with regard to the military training of recruits: Recruits become accustomed to ‘holding their heads high and erect; to standing upright, without bending the back, to sticking out the belly, throwing out the chest and throwing back the shoulders; and, to help them acquire the habit, they are given this position while standing against a wall in such a way that the heels, the thighs, the waist and the shoulders touch it, as also do the backs of the hands, as one turns the arms outwards, without moving them away from the body . . . Likewise, they will be taught never to fix their eyes on the ground, but to look straight at those they pass . . . to remain motionless until the order is given, without moving the head, the hands or the feet . . . lastly to march with a bold step, with knee and ham taut, on the points of the feet, which should face outwards.’ (Foucault, 1979, pp. 135–136) If before the 18th century, the individual’s body and the life of the population were matters of indifference to authorities, after the 18th century, it is possible to argue that all of institutional life became focused on disciplining and improving the individual body and collective life. It is in this context that the concept of the norm became so important. A norm is a socially defined rule that allows us to distinguish between what conforms to accepted standards and what does not. In the biopolitical era, norms are typically understood less as moral rules about what is morally correct or good and more as calculated averages that define what is statistically normal behaviour and what deviates from the norm (Ewald, 1990). In schooling, for example, norms define what level of knowledge each grade should attain. Within each grade, students’ performance is judged in relationship to these norms and as a result, they receive A, B, C, etc. letter grades, so they know where they stand with regard to the norm, (and with regard to each other). The whole learning operation depends on the detailed control of the students’ bodies as they must learn to physically read and write, to sit quietly and listen to instruction, to organize routines around a fixed schedule, and to take steps to improve their abilities. The same can be said about the norms of health in the medical system, the norms of productivity in the workplace, the norms of soldiering in the military, and the norms of “good behaviour” in the prison system. In each case, a disciplinary procedure is instituted to improve the individual’s abilities so that they can become normal (e.g. to enjoy normal health or work at a normal level of productivity). Therefore, with regard to the establishment of norms, and what Foucault called the normalizing society, the problem of deviance became more prominent in the 19th and 20th centuries. The problem of disabilities is a good example of medicalized deviance. Those with disabilities do not fit within the norms of the healthy body and therefore, beginning in the 19th century, scientists and reformers sought their rehabilitation through medical, technological, therapeutic, and educational interventions. We will discuss this further below. Today, the relationship to the body has become even more complex. We are still obliged by different institutions to act on our bodies in specific ways: to be more efficient at work, to recover from injury or illness through the health care system, to develop good study habits at school, etc. However, we are also increasingly concerned to improve our bodies on a voluntary basis. Individually, we turn to experts in a variety of fields who advise us on different procedures to act upon our bodies like exercise regimes, dieting, cosmetic surgery, skin care products, meditation techniques, yoga, sex therapy, life coaching, martial arts, etc. A bewildering amount of information about life improvement and numerous competing options is available. Increasingly we live in an era of medical pluralism, in which no one model of health practice can successfully claim to provide the definitive truth for how to attain health. But as Zygmunt Bauman (2005) argues, the increased capacity to control our bodies in the absence of certainty about which way is best, only increases our anxiety (2005). In addition, the control of the body has become increasingly “molecularized” through the advances of genetic and bio-chemical research. That is, we attempt to act upon and change our bodies at the level of primary biochemical, cellular, molecular processes like ribosomic protein synthesis. Nikolas Rose (2007) has argued that this leads to entirely new forms of somatic (bodily) existence and genetic risk in which we come to define ourselves by our genetic markers and seek to not only cure illness or forestall congenital dispositions to disease but to optimize our existence through genetic engineering, designer pharmaceuticals, and epigenetic therapies. 10.1.2 The Social Construction of Health The sociology of health encompasses social epidemiology, disease, mental health, disability, and medicalization. The principle insight of sociology is that health and illness cannot be simply regarded as biological or medical phenomena. They are perceived, organized, and acted on in a political, economic, cultural, and institutional context. Moreover, the way that we relate to them is in constant evolution. As we learn to control existing diseases, new diseases develop. As our society evolves to be more global, the way that diseases spread evolves with it. According to the World Health Organization (WHO), health “is a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity” (WHO, 2014). What does “health” mean to you? How does the WHO definition relate to contemporary issues of health? Do you believe that there are too many people taking medications in Canadian society? Are you skeptical about people claiming they are “addicted” to gambling or “addicted” to sex? Can you think of anything that was historically considered a disease, but is now considered within a range of normality? Or anything that has recently become known as a disease, whereas before it was considered evidence of laziness or other character flaws? Do you believe all children should receive vaccinations? These are questions examined in the sociology of health. Sociologists may also understand these issues more fully by considering them through one of the main theoretical perspectives of the discipline. The functionalist perspective is a macroanalytical perspective that looks at the big picture, focusing on the way that all aspects of society are integral to the continued health and viability of the whole. For those working within the functionalist perspective, the focus is on how healthy individuals have the most to contribute to the stability of society. Functionalists might study the most efficient way to restore “sick” individuals to a healthy state. The critical perspective is another macroanalytical perspective that focuses on the creation and reproduction of inequality. Someone applying the critical perspective might focus on the relationship between the power of pharmaceutical companies and rates of drug prescription, or between medical knowledge and the way power is exercised through the increased medicalization of the body. Someone applying the interactionist perspective to health might focus on how people understand their health, how their relationship to their bodies is mediated by social concepts of health and illness, and how their health affects their relationships with the people in their lives. 10.1.3 Medical Sociology and the Social Construction of Health If sociology is the systematic study of human behaviour in society, medical sociology is the systematic study of how humans manage issues of health and illness, disease and disorders, and health care for both the sick and the healthy. Medical sociologists study the physical, mental, and social components of health and illness. Major topics for medical sociologists include the doctor-patient relationship, the structure and socioeconomics of health care, and how culture impacts attitudes toward disease and wellness. The social construction of health is a major research topic within medical sociology. At first glance, the concept of a social construction of health does not seem to make sense. After all, if disease is a measurable, physiological problem, then there can be no question of socially constructing disease, right? Well, it’s not that simple. The idea of the social construction of health emphasizes the socio-cultural aspects of the discipline’s approach to physical, objectively definable phenomena. Sociologists Conrad and Barker (2010) offer a comprehensive framework for understanding the major findings of the last 50 years of development in this concept. Their summary categorizes the findings in the field under three subheadings: the cultural meaning of illness, the social construction of the illness experience, and the social construction of medical knowledge. 10.1.4 The Cultural Meaning of Illness Many medical sociologists contend that illnesses have both a biological and an experiential component, and that these components exist independently of each other. Our culture, not our biology, dictates which illnesses are stigmatized and which are not, which are considered disabilities and which are not, and which are deemed contestable (meaning some medical professionals may find the existence of this ailment questionable) as opposed to definitive (illnesses that are unquestionably recognized in the medical profession) (Conrad and Barker, 2010). For instance, sociologist Erving Goffman (1963) described how social stigmas hinder individuals from fully integrating into society. A stigma in general is defined by a “mark” of difference (e.g. a physiological “deformity,” personality “defect,” or status category like race, nationality, or religion) that defines a socially undesirable characteristic. Goffman elaborates: an individual who might have been received easily in ordinary social intercourse possesses a trait that can obtrude itself upon attention and turn those of us whom he meets away from him, breaking the claim that his other attributes have on us (Goffman, 1963). In other words, stigma operates to define a person by a single attribute that makes them seem less than fully human and therefore subject to discriminatory practices, often unthinkingly. In encountering a stigmatized person, we construct a stigma theory that explains his or her inferiority and provides an account of the threat or danger they represent. The stigmatization of illness often has the greatest effect on the patient and the kind of care he or she receives. Facilities for these diseases may be sub-par; they may be segregated from other health care areas or relegated to a poorer environment. Contested illnesses are those that are questioned or questionable by some medical professionals. Disorders like fibromyalgia or chronic fatigue syndrome may be either true illnesses or only in the patients’ heads, depending on the opinion of the medical professional. This dynamic can affect how a patient seeks treatment and what kind of treatment he or she receives. The Social Construction of the Illness Experience The idea of the social construction of the illness experience is based on the concept of reality as a social construction. In other words, there is no objective reality independent of our own perceptions of it. The social construction of the illness experience deals with such issues as the way some patients control the manner in which they reveal their disease and the lifestyle adaptations patients develop to cope with their illnesses. In terms of constructing the illness experience, culture and individual personality both play a significant role. For some people, a long-term illness can have the effect of making their world smaller, more defined by the illness than anything else. For others, illness can be a chance for discovery, for re-imaging a new self (Conrad and Barker, 2010). Culture plays a huge role in how an individual experiences illness. Widespread diseases like AIDS or breast cancer have specific cultural markers that have changed over the years and that govern how individuals — and society — view them. Today, many institutions of wellness acknowledge the degree to which individual perceptions shape the nature of health and illness. Regarding physical activity, for instance, the Public Health Agency of Canada recommends that individuals use a standard level of exertion to assess their physical activity. This rating of perceived exertion (RPE) gives a more complete view of an individual’s actual exertion level, since heart rate or pulse measurements may be affected by medication or other issues (CSEP, N.d.). Similarly, many medical professionals use a comparable scale for perceived pain to help determine pain management strategies. 10.1.5 The Social Construction of Medical Knowledge Conrad and Barker show how medical knowledge is socially constructed; that is, it can both reflect and reproduce inequalities in gender, class, race, and ethnicity. Conrad and Barker (2010) use the example of the social construction of women’s health and how medical knowledge has changed significantly in the course of a few generations. For instance, in the early 20th century, pregnant women were discouraged from driving or dancing for fear of harming the unborn child, much as they are discouraged from smoking or drinking alcohol today. 10.2 Global Health Social epidemiology is the study of the causes and distribution of diseases. Social epidemiology can reveal how social problems are connected to the health of different populations. These epidemiological studies show that the health problems of high-income nations differ greatly from those of low-income nations. Some diseases, like cancer, are universal. But others, like obesity, heart disease, respiratory disease, and diabetes are much more common in high-income countries, and are a direct result of a sedentary lifestyle combined with poor diet. High-income nations also have a higher incidence of depression (Bromet et al., 2011). In contrast, low-income nations suffer significantly from malaria and tuberculosis. How does health differ around the world? Some theorists differentiate among three types of countries: core nations, semi-peripheral nations, and peripheral nations. Core nations are those that we think of as highly developed or industrialized, semi-peripheral nations are those that are often called developing or newly industrialized, and peripheral nations are those that are relatively undeveloped. While the most pervasive issue in the Canadian care system is timely access to health care, other core countries have different issues, and semi-peripheral and peripheral nations are faced with a host of additional concerns. Reviewing the status of global health offers insight into the various ways that politics and wealth shape access to health care, and it shows which populations are most affected by health disparities. One clear trend that has emerged in the social epidemiological literature is the shift in the type of diseases and health issues that affect populations as societies modernize. The epidemiologic transition or “health transition” refers to the long-term change in a population’s dominant health problems or profile from acute infectious diseases to chronic, degenerative diseases as societies go through the process of industrialization (Omram, 1971; Young, 1988). Infectious diseases, like measles, influenza, chronic diarrhea, tuberculosis, plague, etc., refer to diseases caused by micro-organisms such as bacteria or viruses and are often communicable, leading to epidemic outbreaks. These are diseases common to sedentary societies exposed to water-borne pathogens, human waste, the diseases of domesticated animals, nutritional deficits, and periodic famine. Chronic diseases, like cancer, heart disease, diabetes, hypertension and obesity, are non-communicable and characterized by the slow onset of symptoms. They are more characteristic of the causes of death in societies that have higher standards of living, better access to a regular supply of nutritious food, public sanitation measures, and immunization programs to control infectious diseases. They have often been referred to therefore as “diseases of modernization” or “Western diseases” because they are symptomatic of effects of modernization on longevity and lifestyle. 10.2.1 Health in High-Income Nations Obesity, which is on the rise in high-income nations, has been linked to many diseases, including cardiovascular problems, musculoskeletal problems, diabetes, and respiratory issues. According to the Organisation for Economic Co-operation and Development (2013), obesity rates are rising in all countries, with the greatest gains being made in the highest-income countries. The United States has the highest obesity rate for adults, while Canada rated fifth. Wallace Huffman and his fellow researchers (2006) contend that several factors are contributing to the rise in obesity in developed countries: - Improvements in technology and reduced family size have led to a reduction of work to be done in household production. - Unhealthy market goods, including processed foods, sweetened drinks, and sweet and salty snacks are replacing home-produced goods. - Leisure activities are growing more sedentary; for example, computer games, web surfing, and television viewing. - More workers are shifting from active work (agriculture and manufacturing) to service industries. - Increased access to passive transportation has led to more driving and less walking. Obesity and weight issues have significant societal costs, including lower life expectancies and higher shared health care costs. High-income countries also have higher rates of depression than less affluent nations. A recent study (Bromet et al., 2011) shows that the average lifetime prevalence of major depressive episodes in the 10 highest-income countries in the study was 14.6 percent; this compared to 11.1 percent in the eight low- and middle-income countries. The researchers speculate that the higher rate of depression may be linked to the greater income inequality that exists in the highest-income nations. 10.2.2 Health in Low-Income Nations In peripheral nations with low per capita income, it is not the cost of health care that is the most pressing concern; rather, low-income countries must manage such problems as infectious disease, high infant mortality rates, scarce medical personnel, and inadequate water and sewer systems. Such issues, which high-income countries rarely even think about, are central to the lives of most people in low-income nations. Due to such health concerns, low-income nations have higher rates of infant mortality and lower average life spans. One of the biggest contributors to medical issues in low-income countries is the lack of access to clean water and basic sanitation resources. According to a 2011 UNICEF report, almost half of the developing world’s population lacks improved sanitation facilities. The World Health Organization (WHO) tracks health-related data for 193 countries. In their 2011 World Health Statistics report, they document the following statistics: - Globally, the rate of mortality for children under five was 60 per 1,000 live births. In low-income countries, however, that rate is almost double at 117 per 1,000 live births. In high-income countries, that rate is significantly lower than 7 per 1,000 live births. - The most frequent causes of death for children under five were pneumonia and diarrheal diseases, accounting for 18 percent and 15 percent, respectively. These deaths could easily be avoidable with cleaner water and more coverage of available medical care. - The availability of doctors and nurses in low-income countries is one-tenth that of nations with a high income. Challenges in access to medical education and access to patients exacerbate this issue for would-be medical professionals in low-income countries (World Health Organization, 2011). 10.3 Health in Canada Health in Canada is a complex and often contradictory issue. On the one hand, as one of the wealthiest nations, Canada fares well in health outcomes with respect to the rest of the world. The publicly funded health care system in Canada also compares well to the noted issues of the private for-profit system in the United States (especially in terms of overall cost and who gets access to medical care). On the other hand, it is also behind many European countries in terms of key health care indicators such as access to family doctors and wait times for critical procedures. The following sections look at different social aspects of health in Canada. 10.3.1 Health by Race and Ethnicity Unlike the United States, where strong health disparities exist along racial lines, in Canada differences in health between non-indigenous visible minorities and Canadians of European origin disappear once socioeconomic status and lifestyle are taken into account. Moreover, new and recent immigrants from non-European countries tend, in fact, to have better health than the average native-born Canadian does (Kobayashi, Prus, and Lin, 2008). Indigenous Canadians unfortunately continue to suffer from serious health problems. It is estimated that in the 1500s, prior to contact, there were 500,000 aboriginal people living in Canada. Through epidemics of contagious Euro-Asian diseases such as smallpox, measles, influenza, and tuberculosis, aboriginal populations suffered an estimated 93 percent decline (O’Donnell, 2008). Conditions in the late 19th century to the mid-20th century did not improve markedly after indigenous people were moved to reserves. Often lacking adequate drinking water, sanitation facilities, and hygienic conditions, these were ideal settings for the spread of communicable diseases. Death rates from tuberculosis (TB), for example, remained very high for First Nations peoples into the 1950s, long after the use of antibiotics brought TB under control in the rest of Canada. In 2005, the TB rate was still 27 active cases per 100,000 population for aboriginal people, while it was only five active cases per 100, 000 for the rest of the population. Part of the problem is that the percentage of indigenous people living in overcrowded housing on reserves and in the north is five to six times higher than for the general population (Statistics Canada, 2011). Recent crises in Attawapiskat, Ontario, and other First Nations communities with respect to housing, drinking water, and lack of proper water purification systems indicate that these issues have not been resolved (Stastna, 2011). Figure 19.7 shows that life expectancy for Indigenous people (registered Indians) has improved. However, it remains significantly lower than for the average population: Indigenous men and women could expect to live 8.1 and 5.5 fewer years respectively than the average Canadian man and woman (Health Canada, 2005). While infectious diseases are largely regarded now as being under control in aboriginal populations (albeit at higher rates than the Canadian population), Indigenous people suffer disproportionately from chronic health problems like diabetes, heart disease, obesity, respiratory problems, and HIV (Statistics Canada, 2011). The health conditions of off-reserve Indigenous people are also significantly worse than for the average population. While nearly 59 percent of non-Indigenous people in Canada over the age of 20 rated their health as “excellent or very good” in 2006–2007, only 51 percent of First Nations, 57 percent of Métis, and 49 percent of Inuit living off-reserve did so. Similarly 74 percent of non-Indigenous Canadians reported that they had no physical limitations due to ill health, while only 58, 59, and 64 percent of off-reserve First Nations, Métis, and Inuit, respectively, did so (Garner, Carrière, and Sanmartin, 2010). While some of the difference between Indigenous and non-Indigenous health conditions can be explained by financial, educational, and individual lifestyle variables, even when these were taken into account statistically disparities in health remained. The authors of the study on off-reserve indigenous health report that “[s]uch findings point to the existence of other factors contributing to the greater burden of morbidity among First Nations, Métis and Inuit people” (Garner, Carrière, and Sanmartin, 2010, p. iii). 10.3.2 Health by Socioeconomic Status Ximena de la Barra, senior urban advisor to UNICEF, wrote in 1998 that “being poor is in itself a health hazard; worse, however, is being urban and poor” (de la Barra, 1998, p. 46). The context of her statement was global urban poverty, but her conclusions apply to the relationship between poverty and health in Canada as well. Residents of poorer urban areas in Canada have significantly higher hospitalization rates and lower self-reported quality of health than residents of average or wealthy urban areas (see Figures 19.6 and 19.7). Living and growing up in poverty is linked to lower life expectancy, and chronic illnesses such as diabetes, mental illness, stroke, cardiovascular disease, central nervous system disease, and injury (Canadian Population Health Initiative, 2008). In fact actual medical care accounts for only about a quarter of health outcomes, while one-half of a person’s ability to recover from illness is determined by socioeconomic factors, including income, education, and living conditions (CBC, 2014). In an interesting study of 17, 350 British civil servants, it was found that differences in even relatively small disparities of wealth and power between civil service employment grades led to significantly better health outcomes for the privileged. The more authority one has, the healthier one is (Marmot, Shipley, and Rose, 1984). These social determinants of health led the Canadian Medical Association to argue that providing adequate financial resources might be the best medical treatment that can be provided to poor patients. Inner city doctor, Gary Bloch stated, “Treating people at low income with a higher income will have at least as big an impact on their health as any other drugs that I could prescribe them…. I do see poverty as a disease” (CBC, 2013). It is important to remember that economics are only part of the socioeconomic status (SES) picture; research suggests that education also plays an important role. Phelan and Link (2003) note that many behaviour-influenced diseases like lung cancer (from smoking), coronary artery disease (from poor eating and exercise habits), and AIDS initially were widespread across SES groups. However, once information linking habits to disease was disseminated, these diseases decreased in high SES groups and increased in low SES groups. This illustrates the important role of education initiatives regarding a given disease, as well as possible inequalities in how those initiatives effectively reach different SES groups. 10.3.3 Health by Gender Women continue to live longer than men do on average, but women have higher rates of disability and disease. In each age group, men have higher rates of fatal disease, whereas women have higher rates of non-fatal chronic disease. “Women get sicker but men die quicker” might be a way of summing this up (Lorber, 2000). For example, while 4 percent of Canadian men suffer from chronic illnesses, these illnesses affect 11 percent of Canadian women, particularly conditions such as multiple sclerosis, lupus, migraines, hypothyroidism, and chronic pain (Spitzer, 2005). While men’s lower life expectancy is often attributed to three factors — their tendency to engage in riskier behaviour or riskier work than women, their lower use of the health care system (which prevents symptoms from being diagnosed earlier), and their innate biological disposition to higher mortality at every stage of life — it is not as clear why chronic disease affects women in higher proportions. Spitzer notes that gender roles and relations lead to different responses and exposures to stressors, different access to resources, different responsibilities with regard to domestic work and caregiving, and different levels of exposure to domestic violence, all of which affect chronic health issues in women disproportionately. Women are also affected adversely by institutionalized sexism in health care provision. We can see an example of institutionalized sexism in the way that women are more likely to be diagnosed with certain kinds of mental disorders than men are. Psychologist Dana Becker notes that 75 percent of all diagnoses of Borderline Personality Disorder (BPD) are for women according to the Diagnostic Statistical Manual of Mental Disorders. This diagnosis is characterized by instability of identity, of mood, and of behaviour, and Becker argues that it has been used as a catch-all diagnosis for too many women. She further decries the pejorative connotation of the diagnosis, saying that it predisposes many people, both within and outside of the profession of psychotherapy, against women who have been so diagnosed (Becker, N.d.). Many critics also point to the medicalization of women’s issues as an example of institutionalized sexism. Medicalization refers to the process by which previously normal aspects of life are redefined as deviant and needing medical attention to remedy. Historically and contemporaneously, many aspects of women’s lives have been medicalized, including menstruation, pre-menstrual syndrome, pregnancy, childbirth, and menopause. The medicalization of pregnancy and childbirth has been particularly contentious in recent decades, with many women opting against the medical process and choosing a more natural childbirth. Fox and Worts (1999) find that all women experience pain and anxiety during the birth process, but that social support relieves both as effectively as medical support. In other words, medical interventions are no more effective than social ones at helping with the difficulties of pain and childbirth. Fox and Worts further found that women with supportive partners ended up with less medical intervention and fewer cases of postpartum depression. Of course, access to quality birth care outside of the standard medical models may not be readily available to women of all social classes. 10.3.4 Mental Health and Disability The treatment received by those defined as mentally ill or disabled varies greatly from country to country. In post-millennial Canada, those of us who have never experienced such a disadvantage take for granted the rights our society guarantees for each citizen. However, access to things like education, housing, or transportation that most people take for granted, are often experienced very differently by people with disabilities. Mental Health People with mental disorders (a condition that makes it more difficult to cope with everyday life) and people with mental illness (a severe, lasting mental disorder that requires long-term treatment) experience a wide range of effects. According to the 2012 Canadian Community Health Survey, the most common mental disorders in Canada are mood disorders (major depression, bipolar disorder). Over 11 percent of Canadians reported experiencing major episodes of depression in their lifetime (4.7 percent in the previous year), while 2.6 percent reported bipolar disorder in their lifetime (1.5 percent in the previous year) (Pearson, Janz, and Ali, 2013). Major mood disorders are depression, bipolar disorder, and dysthymic disorder. Depression might seem like something that everyone experiences at some point, and it is true that most people feel sad or “blue” at times in their lives. A true depressive episode, however, is more than just feeling sad for a short period; it is a long-term, debilitating illness that usually needs treatment to cure. Bipolar disorder is characterized by dramatic shifts in energy and mood, often affecting the individual’s ability to carry out day-to-day tasks. Bipolar disorder used to be called manic depression because of the way that people would swing between manic and depressive episodes. The second most common mental disorders in Canada are anxiety disorders. Almost 9 percent of Canadians reported experiencing generalized anxiety disorder in their lifetime (2.6 percent in the previous year) (Pearson, Janz, and Ali, 2013). Similar to depression, it is important to distinguish between occasional feelings of anxiety and a true anxiety disorder. Anxiety is a normal reaction to stress that we all feel at some point, but anxiety disorders are feelings of worry and fearfulness that last for months at a time. Anxiety disorders include obsessive-compulsive disorder (OCD), panic disorders, post-traumatic stress disorder (PTSD), and both social and specific phobias. Depending on what definition is used, there is some overlap between mood disorders and personality disorders. Canadian data on the prevalence of personality disorders is lacking but estimates in the United States suggest they affect 9 percent of Americans yearly. In Canada, epidemiological research reporting on antisocial personality disorder shows that about 1.7 percent of the population experience this specific disorder yearly (Public Health Agency of Canada, 2002). The American Psychological Association publishes the Diagnostic and Statistical Manual on Mental Disorders (DSM), and their definition of personality disorders is changing in the fifth edition, which is being revised in 2011 and 2012. In the DSM-IV, personality disorders represent “an enduring pattern of inner experience and behaviour that deviates markedly from the expectations of the culture of the individual who exhibits it” (National Institute of Mental Health). In other words, personality disorders cause people to behave in ways that are seen as abnormal to society but seem normal to them. The DSM-V proposes broadening this definition by offering five broad personality trait domains to describe personality disorders, some related to the level or type of their disconnect with society. As their application evolves, we will see how their definitions help scholars across disciplines understand the intersection of health issues and how they are defined by social institutions and cultural norms. Another fairly commonly diagnosed mental disorder is attention-deficit/hyperactivity disorder (ADHD), which American statistics suggest affects 9 percent of children and 8 percent of adults on a lifetime basis (National Institute of Mental Health, 2005). The New York Times reported American Centers for Disease Control data showing that the diagnosis of children with ADHD had increased by 53 percent over the last decade, raising issues of overdiagnosis and overmedication (Schwarz and Cohen, 2013). Recent data from Canada confirm the increasing rate of prescribed medications and ADHD diagnosis in Canada, although the rates are much lower than those reported in the United States (3 percent for all children aged three to nine, but 4 percent for boys and 5 percent for school-aged children in this age range) (Brault and Lacourse, 2012). ADHD is one of the most common childhood disorders, and it is marked by difficulty paying attention, difficulty controlling behaviour, and hyperactivity. The significant increase in diagnosis and the use of medications such as Ritalin have prompted social debate over whether such drugs are being overprescribed (American Psychological Association, N.d.). In fact, some critics question whether this disorder is really as widespread as it seems, or if it is a case of overdiagnosis. Autism spectrum disorders (ASD) have also gained a lot of attention in recent years. The term ASD encompasses a group of developmental brain disorders that are characterized by “deficits in social interaction, verbal and nonverbal communication, and engagement in repetitive behaviours or interests” (National Institute of Mental Health, 2011b). A report from the American Centers for Disease Control (CDC) suggests that 1 in every 68 children is born with ASD (Centers for Disease Control and Prevention, 2014). This diagnosis is up by 30 percent from the previous estimate that 1 in 88 children is born with ASD. In Canada, a national tracking system is being set up, but a report from the National Epidemiologic Database for the Study of Autism in Canada found increases in diagnosis in Prince Edward Island, Newfoundland and Labrador, and southeastern Ontario ranging from 39 to 204 percent, depending on the region. As an example of social construction of disorders, much of the increase in diagnosis is believed to be due to increased awareness of the disorder rather than actual prevalence, with doctors diagnosing autism more frequently and with children with less severe problems (NEDSAC, 2012). The National Institute of Mental Health (NIMH) distinguishes between serious mental illness and other disorders. The key feature of serious mental illness is that it results in “serious functional impairment, which substantially interferes with or limits one or more major life activities” (National Institute of Mental Health, 2005). Thus, the characterization of “serious” refers to the effect of the illness (functional impairment), not the illness itself. Disability Disability refers to a reduction in one’s ability to perform everyday tasks. The World Health Organization makes a distinction between the various terms used to describe handicaps that are important to the sociological perspective. They use the term impairment to describe the physical limitations, while reserving the term disability to refer to the social limitation. In 2012, 3.8 million Canadians, or 13.7 percent of Canadians aged 15 and over, reported having a disability — a long-term condition or health-related problem — that limited their ability to perform daily tasks. Twenty-six percent of these disabled Canadians had a disability classified as “very severe” (Statistics Canada, 2013). Lyn Jongbloed (2003) notes that conceptions of disability have gone through several shifts in Canada since the 19th century, leading to significant shifts in public policy on disabilities. In the early 19th century, persons with intellectual impairments were often jailed alongside criminals, suggesting that the distinction was not significant from the point of view of public policy. Then between 1860 and 1890, the asylum model of care was developed specifically for the disabled, in large part to protect them or others from harm. People with physical disabilities were not regarded as disruptive so they were not institutionalized. This law and order approach was gradually replaced by medical and economic models that conceptualized disability as a biological reality that called for practices such as rehabilitation. Rehabilitation focused on interventions to treat or cure disabilities so that disabled persons could earn a livelihood and reintegrate into “normal” society. As Jongbloed suggests, “Helping people become economically independent is consistent with the North American ideology of individualism. The economic model of disability is predicated on an individual’s inability to participate in the paid labour force” (2003). Finally, since the 1970s, the medical and economic model has been gradually supplanted, or supplemented, by a sociopolitical model that argues that disability results from a failure of the social environment rather than individual impairment. This led to rights-based challenges of barriers to the disabled and a deinstutionalization movement that saw the closing of the asylum system and its replacement with a community model of care. Before the passage of the Canadian Charter of Rights and Freedoms in 1982, which specifically designated individuals with disabilities as one of four disadvantaged groups protected by the Charter, Canadians with disabilities were often routinely excluded from opportunities and social institutions that many able-bodied persons take for granted. This occurred not only through employment and other kinds of discrimination, but through casual acceptance by most Canadians of a world designed for the convenience of the able-bodied. Imagine being in a wheelchair and trying to use a sidewalk without the benefit of wheelchair-accessible curbs. Imagine as a blind person trying to access information without the widespread availability of Braille. Imagine having limited motor control and being faced with a difficult-to-grasp round door handle. Ableism refers to both direct discrimination against persons with disabilities and the unintended neglect of their needs. It is not the physiological, mental, or medical nature of impairment that disables so much as the way the social world has been constructed to enable some, while disabling others. Ableism is linked to the enduring legacy of stigmatizing persons with disabilities. People with disabilities are stigmatized by the perception that they are, in some manner, ill. Stigmatization means that their identity is spoiled; they are labelled as different, discriminated against, and sometimes even shunned. They are labelled (as an interactionist might point out) and ascribed a master status (as a functionalist might note), becoming “the blind girl” or “the boy in the wheelchair” instead of someone afforded a full identity by society. This can be especially true for people who are disabled due to mental illness or disorders. In response, many disabled groups have begun to assert that they are not disabled, but differently enabled. Their condition is not a form of deviance from the norm, but a different form of normality. As Rod Michalko argues, blindness for example is only seen as a problem or disability from the point of view of sightedness and a world organized for the sighted (Michalko, 1998). As discussed in the section on mental health, many mental health disorders can be debilitating, affecting a person’s ability to cope with everyday life. This can affect social status, housing, and especially employment. According to the a Canadian Human Rights Commission’s Report on Equity Rights of People with Disabilities (2012), people with a disability had a higher rate of unemployment than people without a disability: 8.6 percent to 6.3 percent (2006 data). Disabled men and women are also 8.6 percent and 6.5 percent more likely to be underemployed than men and women without disabilities (respectively). The disabled were also only half as likely to complete a university education as the non-disabled (20.2 per cent versus 40.7 per cent, respectively) are and earned significantly less than they do ($9,557 less per year for men and $8,853 less for women). 10.3.5 Obesity: The Last Acceptable Prejudice What is your reaction to the picture in Figure 19.9? Compassion? Fear? Disgust? Many people will look at this picture and make negative assumptions about the man based on his weight. According to a study from the Yale Rudd Center for Food Policy and Obesity, large people are the object of “widespread negative stereotypes that overweight and obese persons are lazy, unmotivated, lacking in self-discipline, less competent, noncompliant, and sloppy” (Puhl and Heuer, 2009). Historically, in both Canada and elsewhere, it was considered acceptable to discriminate against people based on prejudiced opinions. Even after colonization formally ended with the formation of the Canadian state in 1867, the next 100 years of Canadian history saw institutionalized racism and prejudice against indigenous people. In an example of stereotype interchangeability, the same insults that are flung today at the overweight and obese population (lazy, for instance), have been flung at various racial and ethnic groups in earlier history. Of course, no one gives voice to these kinds of views in public now, except when talking about obese people. Why is it considered acceptable to feel prejudice toward — even to hate — obese people? Puhl and Heuer suggest that these feelings stem from the perception that obesity is preventable through self-control, better diet, and more exercise. Highlighting this contention is the fact that studies have shown that people’s perceptions of obesity are more positive when they think the obesity was caused by non-controllable factors like biology (a thyroid condition, for instance) or genetics. Even with some understanding of non-controllable factors that might affect obesity, obese people are still subject to stigmatization. Puhl and Heuer’s study is one of many that document discrimination at work, in the media, and even in the medical profession. Obese people are less likely to get into college than thinner people, and they are less likely to succeed at work. Stigmatization of obese people comes in many forms, from the seemingly benign to the potentially illegal. In movies and television shows, overweight people are often portrayed negatively, or as stock characters who are the butt of jokes. One study found that in children’s movies “obesity was equated with negative traits (evil, unattractive, unfriendly, cruel) in 64 percent of the most popular children’s videos. In 72 percent of the videos, characters with thin bodies had desirable traits, such as kindness or happiness” (Hines and Thompson, 2007). In movies and television for adults, the negative portrayal is often meant to be funny. “Fat suits” —inflatable suits that make people look obese — are commonly used in a way that perpetuates negative stereotypes. Think about the way you have seen obese people portrayed in movies and on television; now think of any other subordinate group being openly denigrated in such a way. It is difficult to find a parallel example. 10.4 Theoretical Perspectives on Health and Medicine Each of the three major theoretical perspectives approaches the topics of health, illness, and medicine differently. 10.4.1 Functionalism According to the functionalist perspective, health is vital to the stability of the society, and therefore sickness is a sanctioned form of deviance. Talcott Parsons (1951) was the first to discuss this in terms of the sick role: patterns of expectations that define appropriate behaviour for the sick and for those who take care of them. According to Parsons, the sick person has a specific role with both rights and responsibilities. To start with, in the context of modern norms of individualism and individual responsibility, a person has not chosen to be sick and should not be treated as responsible for his or her condition. The sick person also has the right of being exempt from normal social roles; the person is not required to fulfill the obligation of a well person and can avoid normal responsibilities without censure. However, this exemption is temporary and relative to the severity of the illness. The exemption also requires legitimation by a physician; that is, a physician must certify that the illness is genuine. The responsibility of the sick person is twofold: to try to get well and to seek technically competent help from a physician. If the sick person stays ill longer than is appropriate (malingers), he or she may be stigmatized. Therefore, it is sometimes necessary for various forms of social control to bring the behaviour of a sick person back in line with normal expectations. In this model of health, doctors serve as gatekeepers, deciding who is healthy and who is sick — a relationship in which the doctor has all the power. And what about people who are sick, but are unwilling to leave their positions for any number of reasons (personal/social obligations, financial need, or lack of insurance, for instance). 10.4.2 Critical Sociology Theorists using the critical perspective suggest that many issues with the health care system, as with most other social problems, are rooted in capitalist society. A World Health Organization report studying the social determinants of health stated, Poor and unequal living conditions are, in their turn, the consequence of deeper structural conditions that together fashion the way societies are organized – poor social policies and programmes, unfair economic arrangements, and bad politics. These ‘structural drivers’ operate within countries under the authority of governments, but also, increasingly over the last century and a half, between countries under the effects of globalization. This toxic combination of bad policies, economics, and politics is, in large measure, responsible for the fact that a majority of people in the world do not enjoy the good health that is biologically possible (W.H.O., 1988). The reports’ authors noted that the crucial variable affecting health was not so much the overall wealth of a society, but of the equability of the distribution of wealth within societies. Alongside the health disparities created by class inequalities, there are a number of health disparities created by racism, sexism, ageism, and heterosexism. The poor and socially excluded are more likely to experience illness caused by poor diet, physiological and psychological stress, living and working in unhealthy environments, and are less likely to challenge the system. In Canada for example, indigenous people have been disproportionately marginalized from economic power, so they bear a great deal of the burden of poor health. According to critical sociology, capitalism and the pursuit of profit also lead to the problematic commodification of health: the changing of something not generally thought of as a commodity into something that can be bought and sold in a marketplace. In this view, corporations, private insurance companies, pharmaceutical companies and investors have a disproportionate influence over how the health care system is run and funded, which type of diseases are researched, whether cheaper generic versions of patented drugs can be sold, the nature of the health care delivered, and even how the physiology of the human body is understood. One outcome of this is that corporate interests also influence the terms in which debates about public health care are discussed. Corporate think tanks like the Fraser Institute and the CD Howe Institute have long advocated free-market, profit-driven, American-style models rather than publicly funded models to deliver health care in Canada (Carroll and Shaw, 2001). The language with which they approach health care emphasizes “taxpayer rights,” alarming statements about the financial unsustainability of public health care, and the role of “vested interests” in promoting an “outdated” 1960s-era system. Despite the fact that Canadians persistently state that public, universal health care is their central priority, corporate and neoliberal messaging on health care has become increasingly influential over the last three decades. Another critical approach to health and illness focuses on the emergence of biopolitics in the 18th and 19th centuries (Foucault, 1980). Biopolitics refers to the relationships of power that emerge when the task of fostering and administering the “life” of the population becomes central to government. In a variety of different levels and sites in society — from implementing society-wide public health programs and population controls to various forms of discipline exercised over the bodies of patients, soldiers, children, students, and prisoners — modern scientific knowledge on the functioning of the body establishes new power relations between experts (e.g., doctors, psychiatrists, psychologists, sociologists, social workers) and subjects. As a result, increasingly numerous forms of discipline and regulation emerge that seek to act upon the living body and the living population to maximize their potential for health, productivity, efficiency, and docility. Modern biomedicine, for example, is a system of medical practice that defines health and illness in terms of the mechanics of the physical, biological systems of the human body. It works on the basis of a mind/body division that leads the individual to “inhabit” his or her body and its problems in a certain way and to submit, voluntarily or involuntarily, to the expertise of doctors when bodily function deviates from biological norms. It is on the basis of doctors’ claim to biomedical knowledge that individuals submit to more or less mortifying exercises of power and discipline: from dieting and exercise regimes to pharmaceutical drug treatments to caesarian births to chemotherapy and gene therapy. It is interesting in this respect to note the various ways in which the knowledge and authority of doctors and the medical establishment are being challenged in contemporary society. People are increasingly researching and becoming more knowledgeable about their health concerns in a manner that permits them to engage with doctors and medical authorities on a more equal basis. They are also engaging with an expanding range of alternatives to conventional biomedicine: health practices and knowledge such as yoga, fitness regimes, dieting, acupuncture, traditional Chinese medicine, chi gong, naturopathy, homeopathy, chiropractic, and indigenous healing practices. This turn to a model of individualized care for the self — i.e., ways of acting upon the self to transform the self to attain a certain mode of being such as “health” (Foucault, 1997) — has a number of competing implications, however. On the one hand, it enables practices of autonomy and self-formation freed from the power relations of the medical establishment. On the other hand, it can feed into intensified concerns and anxieties with the body that deepen rather than loosen submission to authorities and authoritative knowledge — dieting fads, esoteric knowledge and practices, and nontraditional healers, etc. As Zygmunt Bauman notes, when individuals take on the responsibility for knowledge about their own bodies and health in a pluralistic medical culture in which there are numerous competing and contradicting claims about treatment, the outcome for the individual can be paralyzing rather than liberating (Bauman, 2005). 10.4.3 Symbolic Interactionism According to theorists working in this perspective, health and illness are both socially constructed. As we discussed in the beginning of the module, interactionists focus on the specific meanings and causes people attribute to illness. The term medicalization of deviance refers to the process that changes “bad” behaviour into “sick” behaviour. A related process is demedicalization, in which “sick” behaviour is normalized again. Medicalization and demedicalization affect who responds to the patient, how people respond to the patient, and how people view the personal responsibility of the patient (Conrad and Schneider, 1992). An example of medicalization is illustrated by the history of how our society views alcohol and alcoholism. During the 19th century, people who drank too much were considered bad, lazy people. They were called drunks, and it was not uncommon for them to be arrested or run out of a town. Drunks were not treated in a sympathetic way because, at that time, it was thought that it was their own fault that they could not stop drinking. By the late 19th century however, excessive drinking became regarded as a “disease of the will” — a paradoxical illness that required the patient to actively engage in his or her own treatment, even though the nature of the disease was defined by a defect in the will that undermined his or her ability to do so (Valverde, 1997). In the 20th century, people who drank too much were increasingly defined as alcoholics: people with a psychological dependence, physiological disease, or a genetic predisposition to addiction who were not responsible for their drinking. With alcoholism defined as a disease and not a personal choice, alcoholics came to be viewed with more compassion and understanding, although the paradox of recovery therapies for alcoholics remained. Thus, “badness” was transformed into “sickness.” There are numerous examples of demedicalization in history as well. During the Civil War era, slaves who frequently ran away from their owners were diagnosed with a mental disorder called drapetomania. This has since been reinterpreted as a completely appropriate response to being enslaved. A more recent example is homosexuality, which was labelled a mental disorder or a sexual orientation disturbance by the American Psychological Association until 1973. While interactionism does acknowledge the subjective nature of diagnosis, it is important to remember who most benefits when a behaviour becomes defined as illness. Pharmaceutical companies make billions treating illnesses such as fatigue, insomnia, and hyperactivity that may not actually be illnesses in need of treatment, but opportunities for companies to make more money. Key Terms ableism: Discrimination against persons with disabilities or the unintended neglect of their needs. anxiety disorders: Feelings of worry and fearfulness that last for months at a time. biomedicine: A system of medical practice that defines health and illness in terms of the mechanics of the physical, biological systems of the human body biopolitics: The relationships of power that emerge when the task of fostering and administering the life of the population becomes central to government. care for the self: Ways of acting upon the self to transform the self to attain a certain mode of being (e.g., “health”). chronic diseases: Non-communicable diseases like cancer, heart disease, diabetes, hypertension and obesity, characterized by the slow onset of symptoms. commodification: The changing of something not generally thought of as a commodity into something that can be bought and sold in a marketplace. contested illnesses: Illnesses that are questioned or considered questionable by some medical professionals. demedicalization: The social process that normalizes “sick” behavior. disability: A reduction in one’s ability to perform everyday tasks; the World Health Organization notes that this is a social limitation. epidemiologic transition: The long term change in a population’s dominant health problems or profile from acute infectious diseases to chronic, degenerative diseases as societies go through the process of industrialization. health: A state of complete physical, mental, and social well-being and not merely the absence of disease or infirmity. impairment: The physical limitations a less-able person faces. infectious diseases: Communicable diseases caused by micro-organisms such as bacteria or viruses. legitimation: When a physician certifies that an illness is genuine. medical pluralism: A situation in which no one model of health practice can successfully claim to provide the definitive truth for how to attain health. medical sociology: The systematic study of how humans manage issues of health and illness, disease and disorders, and health care for both the sick and the healthy. medicalization: The process by which aspects of life that were considered bad or deviant are redefined as sickness and needing medical attention to remedy. medicalization of deviance: The process that changes “bad” behaviour into “sick” behavior. mood disorders: Long-term, debilitating illnesses like depression and bipolar disorder. norm: A socially defined standard measure which allows us to distinguish between what conforms to a rule and what does not. personality disorders: Disorders that cause people to behave in ways that are seen as abnormal to society but seem normal to them. public health care: Health insurance that is funded or provided by the government. sick role: The pattern of expectations that define appropriate behaviour for the sick and for those who take care of them. rehabilitation: Interventions to treat or cure disabilities in order to reintegrate disabled persons into “normal” society. social epidemiology: The study of the causes and distribution of diseases. stereotype interchangeability: When stereotypes don’t change, they get recycled for application to a new subordinate group. stigma: A “mark” of difference that defines a socially undesirable characteristic. stigmatization: When someone’s identity is spoiled; they are labelled as different, discriminated against, and sometimes even shunned due to an illness or disability. stigmatization of illness: When people are discriminated against because of illnesses and sufferers are looked down upon or even shunned by society. universal health care: A system that guarantees health care coverage for everyone. 10.5 Further Research Spend some time on the two websites below. How do they present differing views of the vaccination controversy? Vaccination: Defending Your Right to Know and Freedom to Choose: http://www.nvic.org/nvic-vaccine-news/november-2014/vaccination–defending-your-right-to-know-and-free.aspx Shot by Shot: Story Gallery: http://www.shotbyshot.org/story-gallery/. Study this 2000-2015 W.H.O. map on global life expectancies. What trends do you notice?: http://gamapserver.who.int/gho/interactive_charts/mbd/life_expectancy/atlas.html. Is ADHD a valid diagnosis and disease? Some think it is not. This article discusses ADHD in children and youth [PDF]: http://www.heretohelp.bc.ca/sites/default/files/attention-deficit-hyperactivity-disorder-in-children-and-youth.pdf. Should alcoholism and other addictions be medicalized? Read and watch a dissenting view: http://abcnews.go.com/Health/MindMoodNews/addiction-treatment-medicalization-wrong-approach/story?id=13642451. 10.6 References Aston, J. (2012). MMR doctor John Walker-Smith wins High Court appeal. The Independent. Retrieved January 2, 2016 from http://www.independent.co.uk/life-style/health-and-families/health-news/mmr-doctor-john-walker-smith-wins-high-court-appeal-7543114.html. American Psychological Association. (n.d.) Understanding the Ritalin debate. American Psychological Association. Retrieved December 14, 2011 from http://www.apa.org/topics/adhd/ritalin-debate.aspx. Bauman, Z. (2005). Liquid life. Cambridge, UK: Polity Press. Becker, D. (n.d.) Borderline personality disorder: The disparagement of women through diagnosis. Retrieved December 13, 2011 from http://www.awpsych.org/index.php?option=com_content&view=article&id=109&catid=74&Itemid=126. Brault, M.C. & Lacourse, É. (2012). Prevalence of prescribed attention-deficit hyperactivity disorder medications and diagnosis among Canadian preschoolers and school-age children: 1994-2007. Canadian Journal of Psychiatry, 57(2), 93-101. Bromet, E., Andrade, L.H., Hwang, I., Sampson, N.A. Alonso, J., de Girolamo, G., … Kessler, R. C. (2011). Cross-national epidemiology of DSM-IV major depressive episode. BMC Medicine, 9:90. Retrieved December 12, 2011 from http://www.biomedcentral.com/1741-7015/9/90. Canadian Human Rights Commission. (2012). Report on equality rights of people with disabilities. [PDF] Minister of Public Works and Government Services. Catalogue no. HR4-20/2012E-PD. Retrieved July 30, 2014 from http://www.chrc-ccdp.ca/sites/default/files/rerpd_rdepad-eng.pdf. Canadian Population Health Initiative. (2008). Reducing gaps in health: A focus on socio-economic status in urban Canada. [PDF] Ottawa: Canadian Institute for Health Information. Retrieved July 29, 2014 from https://secure.cihi.ca/free_products/Reducing_Gaps_in_Health_Report_EN_081009.pdf. Carroll, William and Murray Shaw. (2001). Consolidating a neoliberal policy bloc in Canada, 1976 to 1996. Canadian Public Policy, 27(2): 195-217. CBC. (2013). Treating poverty works like medicine, doctors say: Financial support can pay off with better health. CBC News. Retrieved July 29, 2014 from http://www.cbc.ca/news/health/treating-poverty-works-like-medicine-doctors-say-1.1365662. CBC. (2014). Project money: Health and wealth. The Current. Retrieved July 29, 2014 from http://www.cbc.ca/thecurrent/project-money/2014/07/15/health-and-wealth/. Centers for Disease Control and Prevention. (2014, March 28). Prevalence of autism spectrum disorder among children aged 8 years [PDF] — Autism and developmental disabilities monitoring network, 11 Sites, United States, 2010. MMWR, 63(2): 1-21. Retrieved August 2014, from http://www.cdc.gov/mmwr/pdf/ss/ss6302.pdf. Centers for Disease Control. (2011). Pertussis. The Centers for Disease Control and Prevention. Retrieved December 15, 2011 from http://www.cdc.gov/pertussis/outbreaks.html. Conrad, P. & Barker, K. (2010). The social construction of illness: Key insights and policy implications. Journal of Health and Social Behavior, 51(1 suppl), S67–S79. Conrad, Peter and Joseph W. Schneider. (1992). Deviance and medicalization: From badness to sickness. Philadelphia, PA: Temple University Press. CNN. (2011). Retracted autism study an ‘elaborate fraud,’ British journal finds. CNN, January 5. Retrieved December 16, 2011 from http://www.cnn.com/2011/HEALTH/01/05/autism.vaccines/index.html. CSEP. (n.d.) PAL Physical activity line: Rating of perceived exertion scale. [PDF] Canadian Society for Exercise Physiology. Retrieved July 27, 2014 from http://www.physicalactivityline.com/pdf_files/pal-doc-perceivedexertionscale.pdf. de la Barra, Ximena. (1998). Poverty: The main cause of ill health in urban children. Health Education & Behavior, 25, 1: 46-59. Devlin, K. (2008). Measles worries MMR as vaccination rates stall. The Telegraph. Retrieved January 19, 2012 from http://www.telegraph.co.uk/news/uknews/3074023/Measles-worries-as-MMR-vaccination-rates-stall.html. Ewald, F. (1990). Norms, discipline and the law. Representations, 30, 138-161. Foucault, M. (1980). The history of sexuality. Volume one: An introduction. NY: Vintage Books. Foucault, Michel. (1997). The ethics of the concern of the self as a practice of freedom. In Paul Rabinow (Ed.), Ethics: subjectivity and truth (pp. 281-302). NY: New York Press. Fox, B. and D. Worts. (1999). Revisiting the critique of medicalized childbirth: A contribution to the sociology of birth. Gender and Society, 13(3):326–346. Garner, Rochelle, Gisèle Carrière, Claudia Sanmartin. (2010, June). The health of First Nations living off-reserve, Inuit, and Métis adults in Canada: The impact of socio-economic status on inequalities in health. [PDF] Statistics Canada, Catalogue no. 82-622-X No. 004. Retrieved July 28, 2014, from http://www.statcan.gc.ca/pub/82-622-x/82-622-x2010004-eng.pdf. Goffman, E. (1963). Stigma: Notes on the management of spoiled identity. London: Penguin. Health Canada. (2005). 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Long Desciptions \| Date \| Males life expectancy \| Female life expectancy \| \|---\|---\|---\| \| 1980 \| 60.9 years \| 68.0 years \| \| 1990 \| 66.9 years \| 74.0 years \| \| 2000 \| 68.9 years \| 76.6 years \|	16,026	common-pile/pressbooks_filtered	https://openpress.usask.ca/soc112/chapter/normality-and/	pressbooks	pressbooks-0000.json.gz:63378	https://openpress.usask.ca/soc112/chapter/normality-and/
V5G7GkZAYK64J_P6	Modern practice of the electric telegraph; a technical handbook for electricians, managers, and operators, with 185 illustrations. By Frank Leonard Pope.	AMERICAN TELEGRAPHY MORSE (SAMUEL FINLEY BREESE), Inventor of the recording electro-magnetic telegraph, born in Charlestown, Mass., April 27, 1791; graduated at Yale, 1810; studied art in the Royal Academy of London, 1811-15, under Benjamin West. In 1829 he again visited Europe for further study of his profession, and while returning home in 1832, on board the ship Sully, conceived and made drawings of his recording telegraph (see J. D. REID : The Telegraph in America^ chapters vi., vii.). From this time until his death he was unremittingly employed with his invention, passing meantime through many vicissitudes of fortune, and some most painful experiences. He was first professor of fine arts in the University of the City of New York, in one of the rooms of which institution he set up in 1835 his first crude recording telegraphic apparatus, now preserved in the cabinet of the Western Union Company in New York. In 1837, Alfred Vail, a skillful mechanic and inventor, became his partner in the enterprise. Vail entirely reconstructed the apparatus, and embodied it in the practical form in which it was first introduced to the commercial world. After a series of discouragements that would have utterly disheartened most men, Morse, assisted by Vail, established in 1844, under an appropriation from Congress, the first line between Washington and Baltimore. On May 24 of that year, Morse put to the test the great experiment on which his mind had been laboring for many anxious and weary years. His triumph was complete. Honors and riches were showered upon him at home and abroad. Professor Morse was a man of great simplicity of character, firm in his friendships, and most persistent and exhaustive in all his undertakings. He wielded the pen of a ready writer, and his genius, learning, and taste were illustrated by numerous contributions to the press, evincing not only graceful rhetoric but elaborate and well-sustained argument. On June 10, 1871, a bronze statue of Morse, erected by the contributions of the thousands of telegraphic employees in America, was unveiled with imposing ceremonies in Central Park, New York. He died in New York, April 2, 1872. PREFACE. A, MOST a quarter of a century has passed since the publication of the first edition of this work. During that period, and more especially during the past ten years, the progress which has been made in the application of electricity to the industrial arts has been literally unprecedented, while the extraordinary practical results which have been attained have exerted a reflex action in stimulating in an equal degree the advancement of electrical science ; an advancement which has not been without its influence upon the theory and practice of the electric telegraph. This circumstance has at length rendered necessary, not a mere revision of the original treatise, but the preparation, in fact, of an entirely new work throughout. To the intelligent and observant mind of youth, the art of telegraphy possesses a singular fascination, and in many instances its pursuit tends to excite a spirit of scientific inquiry, not only commendable in itself, but valuable as establishing a sure foundation for future success in broader fields of labor. It has been the aim of the author to supply a knowledge, not only of the principles and practice of telegraphy, but of the theory of electricity and the methods of electrical measurement, which should be of the highest possible value to every person entrusted with the care and management of telegraphic apparatus. It has, however, been deemed advisable to somewhat restrict the scope of the work, and hence the automatic, type-printing, synchronous, submarine, and other methods, requiring on the part of the practitioners a special training apart from a knowledge of the ordinary system, have been excluded. The construction and maintenance of aerial, subterranean, and submarine lines has also, by a natural process of evolution in the progress of viii . Preface. the art, become a separate profession, and the subject can therefore receive but brief notice in a work primarily designed for the guidance and instruction of the practical operator. In the treatment of the subject, the use of mathematics has been rendered unnecessary by the free introduction of concrete examples, illustrative of methods and processes of arithmetical computation available in electrical investigations. From the many methods of electrical measurement, as applied to the solution of practical problems, a selection has been made, embracing only those which have proved to be most directly applicable to every-day work. The numerous authorities which have been consulted in the preparation of the present treatise have been carefully indicated in the foot-notes ; in many instances with the addition of the titles of publications which may profitably be consulted by the student desiring to investigate more minutely some particular branch of the subject. These references are intended to constitute, in some sense, a key to the standard literature of electricity, although from the nature of the case, by no means an exhaustive one. It is hoped that the brief biographical notices of men who have distinguished themselves in connection with electrical science will be found to add something to the value of the work, especially as the facts given are sometimes difficult of access to the ordinary reader. The author acknowledges with pleasure his indebtedness to many friends for courtesies extended, especially to Professor Moses G. Farmer of Eliot, Me., and Messrs. E. M. Barton, of the Western Electric Company of Chicago, E. S. Greeley of New York, and Edward Weston, of Newark, N. J. SOURCES OF ELECTRICITY. Origin of Electricity, §§ 6, 7. — Voltaic Element, 8. — Description of the Typical Cell, 9, 10. — Phenomena of Cell, n, 12, 13. — Chemistry of the Voltaic Effect, 14, 15. — Gravity Cell, 16. — Specific Gravity, 17. — Hydrometer, 18. — Charging the Cell, 19, 20, 21. — Copper and Zinc Solutions, 22. — Specific Gravities of Battery Solutions, 23. — Installation of Gravity Cell, 24, 25. — Modified Form of Copper Plate, 26, 27. — Formation of Electric Circuit, 28, 29, 30. — Nomenclature of Electric Circuit, 31. — Chemical Reactions arising in Closed Circuit, 32. — Effect of Continued Action, 33, 34, 35. — Rate of Consumption of Material, 36. — Maintenance of Cell, 37. — Prevention of Evaporation, 38, 39. — Dismantling Cell, 40. — Diffusion of Solution within Cell, 41, 42. — Neutralizing Zinc Solution, 43. — Waste Products of Cell, 44, 45. — Other Forms of Cell, 46, 47. — Lockwood Cell, 48. — Daniell Cell, 49, 50. — Maintenance of Daniell Cell, 51. — Renewal of Daniell Cell, 52. — Intermingling of Solutions, 53, 54. — Choice of Battery Materials, 55, 56. — General Directions for Care of Cells, 57. — Oxide of Copper Cell, 58. — Setting Up and Maintaining Oxide of Copper Cell, 59. — Chemical Reactions of Oxide of Copper Cell, 60. — Grove and Bunsen Cells, 61. — Wasteless Battery Zinc, 6ia 3 Magneto-Electricity, § 62. — Magnetism, 63. — Magnetic Needle, 64. — Phenomena of Magnetic Induction, 65. — Polarity of Magnet, 66. — Horseshoe Magnet and Armature, 67. — Magnetic Spectrum, 68. — Magnetic Field, 69. — Lines of Magnetic Force, 70, 71. — Attraction and Repulsion, 72. — Electric Current Produced by Magnetic Field, 73. 74- — Transformation of Mechanical Power into Electricity and Heat, 75. — Direction of Induced Current, 76. — Mutual Reactions of Current and Magnet, 77. — Summary of Magneto-Electric Phenomena, 78. — Dynamo-Electric Machine, 79. — Theoretical Dynamo, 80, 81.— Frictional Electricity, 82. — Thermo-Electricity, 83 24 THEORY OF QUANTITATIVE ELECTRICAL MEASUREMENT. Electric Current, § 85. — Manifestations of Current, 86. — Importance of Quantitative Measurement, 87. — Fundamental Units of Mass, Space, and Time, 88. — Illustration of Absolute System of Measurement, 89. — Derivation of Electrical and Magnetic Units, 90. — C. G. S. Units of Force and Work, 91. — Conservation of Force, 92. — Electric Field of Force, 93. — Relation of Current Force to Mechanical Force, 94. — Galvanoscope and Galvanometer, 95. — Tangent Galvanometer, 96.— Character of Electrical Measurements, 97. — Characteristics Capable of Measurement, 98. — Apparatus for Measurement, 99. — Ammeter, Voltmeter, and Calorimeter, 100 35 THE LAWS AND CONDITIONS OF ELECTRICAL ACTION. Apparatus Required by Student, § 101. — Construction of Tangent Galvanometer, 102, 103, 104, 105. — Construction of Rheostat, 106. — Preparation for Experiments, 107. — Effect of Varying Number of Cells in Series, 108.— Cells in Parallel Series, 109. — Cells in Parallel, no. — Increasing Length of Conducting Circuit, in, 112, 113. — Conditions which Determine Quantity of Current, 114. — Resistance, 115. — Conductors and Insulators, 116, 117. — Specific Resistance of Different Metals, 1170. — Conditions Affecting Resistance, 118. — Provisional Theory of Electricity, 119. — Mechanical Analogue of Electrical Action, 120. — Conception of Potential and Electromotive Force, 121. — Practical Electric Units, 122. — Ampere, 123. — Coulomb, 123^. — Volt, 124. — Ohm, 125. — Resistance of Liquids, 126. — Ohm's Law, 127. — Joule's Law, 128, 129. — Experimental Proof of Ohm's Law, 130. — Internal Resistance of Cell, 131. — First Case, 132. — Second Case, 133. — Law of Joint Resistances, 134, 135. — Third Case, 136, 137, 138, 139. — Branch or Derived Circuits, 140. — Electric Potential, 141, 142. — Illustration of Fall of Potential, 143.— Fall of Potential Proportionate to Resistance, 144. — Graphic Illustration of Electric Circuit, 145. — Fall of Potential in Non-homogeneous Circuit, 146. — Electrostatic Capacity, 147. — Farad, 148. — Power, or Rate of Work, 149. — Watt, 150. — Current Induction, 151. — Electrical Dimensions of Voltaic Cell, 152. — E. M. F. and Resistance of Cell, 153.— Quantity and Cost of Materials Consumed in Battery, 154, 155, 156. — Production of Electricity in Proportion to Material Consumed, 157. — Con- sumption of Material in Series of Cells, 158. — Electrical Dimensions of Edison-Lalande Cell, 159. — Effect of Temperature upon Resistance of Metallic Conductors, 160, 161. — Effect of Temperature upon Resistance of Liquids, 162. — Effect of Temperature upon Resistance of Daniell Cell, 163, 164 45 Elements of Electro-Magnet, §§ 166, 167. — Polarity of Electro-Magnet Determined by Direction of Current, 168. — Lines of Force as a Measure of Magnetic Field, 169, 170. — Unit of Magnetism, 171. — Magneto-motive Force, 172. — Effect of Iron in Helix, 173. — Effect of Magnetization upon Soft Iron, 174, 175. — Magnetic Saturation, 176. — Magnetization Proportional to Ampere-turns, 177. — The Magnetic Circuit, 178. — Magnetic Permeability, 179. — Law of Magnetic Circuit, 180. — Determination of Magnetic Reluctance, 181. — Ratio of Attractive Force to Distance, 182. — Construction of Telegraph Magnet, 183. — Theoretical Proportions of Telegraph Magnet, 184. — Effect of Position of Windings, 185. — Helix of Coil, 186. — Relation of Thickness and Length of Wire to Number of Turns, 187. — Dimensions and Resistances of Magnet Wires, 188. — Thickness of Spaces between Turns of Wire, 189. — American Standard Wire Gauge, 190. — British Standard Wire Gauge, 191. — Instruments for Gauging Wire, 192. — Adaptation of Magnets to Working Currents, 193, 194. — Spectrum of Electro-Magnet, 194. — Magnetic Hysteresis, 195. — Induction of a Current upon Itself, 196. — Magnet Cores must not be Hardened, 197. — Effect of Self-induction and Hysteresis in Telegraph Magnets, 198. — Other Indirect Causes of Retardation in Electro-Magnets, 199. — Electro-Magnet • with Polarized Armature, 200, 201. — Combinations of Permanent and Electro-Magnets, 202 80 TELEGRAPHIC CIRCUITS. Telegraphic Circuits, §§ 203, 204, 205. — Open and Closed Circuits, 206. — Drawings of Electric Apparatus, 207. — Conventional Representations of Circuits and Apparatus, 208. — The Earth as an Electrical Conductor, 209. — Ground Connection, 210. — Advantages of the Earth Circuit, 211. — Open Circuit, 212. — Closed Circuit, 213. — American Modification of Closed Circuit, 214. — Comparative Advantages of Different Plans, 215. — Position of Battery in Closed Circuit, 216. — General Considerations respecting Telegraphic Circuits, 217. — Relation of Conductivity to Insulation Resistance, 218. — Effect of Imperfect Insulation, 219. — Working Efficiency of Telegraphic Circuit, 220. — Telegraphic Conductors, 221, — Iron Wires, 222. — Office Wires, 223.— Copper Line Wires, 224. — Telegraphic Line Insulators, 225. — Defects of Glass Insulator, 226. — Resistance Influenced by Form of Insulator, 227. — Hard Rubber Insulator, 228. — Paraffin Insulator, 229. — Porcelain Insulator, 230. — Defective Insulation of American Lines, 231, 232, 233. — Distribution of Potentials in Telegraphic Circuits, 234. — Potential in Perfectly Insulated Circuit, 235. — Determination of Potential by Calculation, 236. — Potentials within the Battery, 237, 238, 239, 240. — Potentials in Imperfectly Insulated Circuit, 241. — Effect of Imperfect Insulation upon Flow of Current, 242. — Resistance and Current in Leaky Lines, 243. — Computation of Working Efficiency of Line, 244, 245. — Effect of Position of Fault, 246. — Best Position of Batteries in Circuit, 247. — Intermingling of Currents on Different Lines, 248. — Remedy for Cross-Current, 249, 250. — Value of Poles and CrossArms as Insulators, 251. — Tests of Resistance of Cross-Arms, 252. — Tests of Glass Insulators, 253. — Importance of High Working Efficiency, 254. — Best Method of Improving Efficiency, 255, 256... 102 EQUIPMENT OF AMERICAN TELEGRAPH LINES. Apparatus Essential in Telegraphy, § 257. — Construction of Key, 258. — Modifications of Key, 259. — Adjustment of Key, 260. — Sounder, 261. — Short Line Instrument, 262. — Adjustment of Sounder, 263. — Pocket Apparatus, 264. — Box Sounder, 265. — Working by Relay and Local Circuit, 266. — Construction of Relay, 267. — Adjustments of Relay, 268. — Register, 269, 270. — Adjustments of Register, 271. — Causes of Defective Marking, 272. — Ink-Writing Register, 273. — Circuits of American System, 274. — Arrangements of Apparatus at Way-Station, 275. — Connections of Apparatus of Way-Station, 276. — Manipulation of Switchboard, 277. — Testing for Disconnection, 278. — Reporting Result of Test, 279. — Wedge Cut-Out, 280. — Multiple Wire Switchboard, 281. — Multiple Spring-Jack, 282. — Universal Switchboard, 283. — Manipulation of Universal Switchboard, 284. — Arrangement of Apparatus of Terminal Station, 285. — Terminal Switchboard, 286. — Instrument Tables, 287. — Lightning Arrester, 288. — Plate Arrester, 289.— Safety Fuse, 290. — Inspection and Care of Arresters, 291. — Repeater, 292. — Manual and Automatic Repeaters, 293. — Button Repeater, 294. — Wood's Repeater, 295. — Management of Button Repeater, 296. — Milliken Automatic Repeater, 297. — Management of Automatic Repeaters, 298. — DynamoElectric Generator, 299. — Characteristics of Dynamo-Current, 300. — Electro-Magnetic Field, 301. — Commutator, 302. — Characteristics of Dynamo, 303. — Dynamo in Potential Series, 304. — Positive and Negative Dynamo Series, 305. — Arrangement of Shunt Coils, 306. — Capacity of Dynamo Generator, 306^. — Multiple Telegraphy, 307. — Differential Electro-Magnet, 308. — Construction of Differential Magnet, 309. — Single-Current Duplex, 310. — Circuits of Single- Current Duplex, 311. — Artificial Line, 312. — Balancing Resistance, 313. — Electrostatic Capacity of Line, 314. — Electrostatic Accumulation upon Insulated Conductor, 315. — Effect of Currents of Charge and Discharge, 316. — Condenser, 317. — Ground and Spark Coils, 318. — Double-Current Duplex, 319. — Quadruplex, 320. — Principle of Diplex, 321, 322. — Operation of Diplex, 323. — Diplex and Contraplex Combined, 324. — Quadruplex worked by DynamoCurrents, 325. — Distribution of Currents in Quadruplex Apparatus, 326, 327. — Practical Management of Quadruplex, 328. — Adjustment of Apparatus, 329. — Repeaters for Multiple Telegraph Systems, 329* 138 TESTING TELEGRAPH LINES. Object of Tests, § 330. — Faults and Interruptions, 331. — Testing for Disconnection, 332, 333.— Testing for Partial Disconnection, 334. — Testing for Escape, 335.— Testing for Cross, 336. — Principle of Cross Test, 337, 338, 339. — Testing by Quantitative Measurement, 340. — Wheatstone Bridge, 341. — Best Ratio of Electromotive Forces and Resistances, 342. — Principle of Wheatstone Bridge, 343. — Actual Construction of Bridge, 344. — Galvanometer for Wheatstone Bridge, 345. — To Measure the Conductivity Resistance of a Telegraph Line, 346. — Conductivity Resistance by Loop Method, 3463. — Earth Currents, 347. — Measurement of Resistance of Ground Plate at Distant Station, 348. — Measurement of Insulation Resistance of Line, 349. — Location of Position of a Ground, 350. — Location of Position of an Escape, 351. — Method of Double Measurement, 352. — Loop Test, 353. — Varley's Loop Test. 354. — To Locate a Cross, 355, 356, 357. — To Locate a Bad Joint or Abnormal Resistance, 358. — Measurement of very High Resistances, 359. — Shunts of Galvanometers, 360. — Measurement by Deflections, 361. — Measurement of Resistance of Insulators, 362. — Measurement of Internal Resistance of Battery, 363, 364. — Measurement of Resistance of Galvanometer, 365. — Differential Galvanometer, 366. — Testing for Insulation by Received Currents, 367. — Use of Voltmeter and Ammeter in Telegraphic Testing, 368. — The Weston Ammeter and Voltmeter, 369. — Recording Tests of Conductivity and Insulation, 370 190 HINTS TO LEARNERS. Formation of the Telegraphic Code, § 371. — The American Morse Code, 372. — Learning the Code, 373. — Handling the Key, 374. — Elementary Principles of Code, 375. — Preliminary Practice with the Key, 376. — Exercises upon Code Characters, 377. — Reading by Sound, 378, 379. — A Parting Word, 380 216 INTRODUCTORY. 1. Fundamental Principles. — The electric telegraph is an apparatus by means of which physical effects may be instantaneously produced in distant places. Such effects are technically termed signals. 2. The art of electric telegraphy consists in the production, control, and organization of electric signals. The signals employed in telegraphy may be either visible or audible. Visible signals may be either evanescent, as in the needle telegraph used in Great Britain, and in some forms of apparatus employed in working long submarine cables, or permanent ', as in the case of the Morse register, and in the instruments used on submarine cables of comparatively moderate length. Audible signals are produced by the sounder, and some other less common forms of apparatus. tricity. 4. Nature of Electricity. — We do not as yet know ; perhaps we never shall know with certainty, what the agent we call electricity really is. Formerly it was assumed to be an imponderable fluid. This hypothesis was suggested by Franklin. In later years it gradually came to be regarded as one of the many different forms of energy, or, in other words, as a peculiar affection of the particles of ordinary matter. Recent scientific opinion shows a marked tendency fied form. 1 This conception of the essential nature of electricity appears to be the logical outgrowth of the opinions held, more or less definitely, by such philosophers as Franklin, Cavendish, Faraday, Henry, Thomson, and, more especially, Clerk-Maxwell. The theoretical side of the question is discussed with great ability by Oliver J. Lodge, in his Modern Views of Electricity, while its latest aspects are summarized in a valuable paper by Professor William A. Anthony: "A Review of Modern Electrical Theories," Electrical Engineer, ix. 43 ; Trans. Am. Inst. Elec. Eng., vii. 33. For practical purposes, however, it is fortunately not in the least necessary that we should know what electricity is, nor that we should commit ourselves to any particular assumption as to its essential nature. A thorough knowledge of the physical effects which it is capable of producing under different conditions, and of the laws which govern its action, are all that the practical electrician needs to acquire. conductor or conducting circtiit. (iii) Means for controlling the flow of electricity for the purpose of producing signals, termed the transmitter. (iv) Means for indicating or recording signals, termed the receiver. 1 Electricity and magnetism are not forms of energy ; neither are they forms of matter. They may, perhaps, be provisionally defined as properties or conditions of matter ; but whether this matter be the ordinary matter, or whether it be, on the other hand, that all-pervading ether by which ordinary matter is everywhere surrounded, is a question which has been under discussion, and which may now be fairly held to be settled in favor of the latter view.— DANIELL : Principles of Physics [zd ed.], 532. 6. Origin of Electricity. — Electricity, or, more properly, electrical action, may be produced in several known ways. Although electricity, whatever may be its origin, is demonstrably one and the same thing,1 it has nevertheless become customary to speak of it conventionally, under different names, indicative of its origin. Thus, we have, principally : There are other means of producing electrical manifestations, which have as yet no practical utility for the purpose under consideration, and need not be further considered here. Of those which have been specifically mentioned, chemical and magneto-electricity only, have proved by experience to be adapted to the requirements of the art of telegraphy. 7. Chemical Electricity. — The effects of electricity are most conveniently studied in connection with that form which has its origin in chemical decomposition, especially as it is by the agency of chemical electricity that nearly all the telegraphic apparatus of the world is operated, 8. The Voltaic Element. — The electricity which is employed in telegraphy is usually derived from one or more batteries, each of which is composed of a greater or less number of cells connected Together in a series. A single cell is termed a voltaic or galvanic element. 1 This fact was first experimentally established by Faraday in 1832. His account of this investigation is very instructive, and is given at length in his Experimental Researches (third series), vol. i. pp. 76-109. FIG. i. Separate parts of Gravity Cell. At the right of this is a mass of zinc weighing about 3 Ibs., which has been cast in an iron mould in the form represented. It is proTided with a hanger by means of which it may be suspended from the upper edge of the jar, and also with a damp-screw by means of which a metallic wire may be securely, but removably, attached to it. At the left of the jar is seen a triple plate of thin rolled copper, spread out laterally into the form shown, which is designed to be placed in the bottom of the glass cell. Each separate plate may be cut in the form shown in Fig. 2, the three being then united by a single copper rivet at the middle, and the free ends separated radially, as in Fig. i, before placing in the jar. A vertical copper wire «is permanently riveted to the copper plate. It must not be soldered. The wire is made long enough to extend some 6 in. or 7 in. above the top of the jar. It passes loosely through the bore of a small glass tube, the reason for which is here- Phenomena of the Cell. after explained (27). It is provided at its upper end with a brass clamp termed the copper-connector. Instead of using a glass tube, it is quite usual to substitute a piece of wire covered with a coating of gutta-percha, india-rubber, or other flexible material impervious to the solution. The particular form of copper-connector shown in the figure consists of a short cylindrical piece of brass, perforated with a longitudinal hole for receiving the ends of the wires, into which enter transverse . thumb - screws for plete, consists of the several parts described, assembled together in the relation shown in Fig. 4, which also shows the jar filled with water to within i in. of the top. Care must be observed, in hanging the zinc, not to fracture the glass jar. It is very essential that the water for charging a voltaic element should be both pure and soft. Impure or hard water obstructs, and sometimes altogether prevents, the proper action of the chemicals. certain portion of the oxygen of the water enters into chemical combination with the metal, forming the compound termed oxide of zinc. A thin coating of this oxide ultimately covers the surface of the zinc plate, giving it a dull bluish gray color, and preventing further oxidization. At the same time the hydrogen which was associated with the oxygen in the decomposed water, is set free, and collects in bubbles which adhere to the surface of the zinc plate. When these bubbles are detached they rise to the surface of the water and the contained hydrogen escapes into the air.2 13. This process of oxidization will be recognized as identical with that which takes place in the rusting of iron when exposed to the action of moisture. It is also the same, from a chemical point of view, as the process of combustion or burning. No perceptible effect is produced upon the copper, because the oxygen has less affinity for this metal than it has for hydrogen, and hence has no tendency to separate from the water. 14. Chemistry of the Voltaic Effect.— If now a small quantity of sulphuric acid were to be added to the water contained in the jar, and at the same time the zinc and copper be joined together by a metallic wire in the air outside the jar, a much more vigorous chemical action will immediately set in. The dissolution of the zinc in the liquid will go on with increased rapidity, attended with the evolution of hydrogen in bubbles, not as before upon the surface of the zinc, but upon the copper. 3 15. Although the chemical action in the case just supposed is attended by the development of electricity, yet such an organization, as a generator of electricity for telegraphic purposes, -would be of little practical utility. The chemical action, though vigorous at first, quickly falls off, and in a short time nearly or quite ceases. This effect arises from the adherence of the liberated hydrogen to the sur- 3 In a chemical compound the qualities of the constituents are wholly merged in those of the product, and this circumstance distinguishes a true compound from a mechanical mixture in which the qualities of each ingredient are to a greater or less extent preserved. . . . Chemical combinations always take place in certain definite proportions, either by weight or measure. . . . The atomic theory supposes that two atoms of hydrogen combine with one atom of oxygen to form a molecule of water, and since each atom of oxygen weighs 16 times as much as an atom of hydrogen, the two substances must combine in the proportion of 2 : 16, or i : 8. This principle is known in chemistry as the law of definite proportion.— COOKE : New Chemistry^ 104-8. 3 The chemical reaction is as follows : — Sulphuric acid is composed of hydrogen 2 parts, sulphur i part, oxygen 4 parts ; in chemical notation (H» SO). The sulphur and oxygen unite with the zinc, forming sulphate of zinc, composed of zinc i part, sulphur i part, and oxygen 4 parts (Zn SO4), which remains in solution in the water, while the hydrogen is set free at the copper plate. The Hydrometer. face of the copper, preventing contact of the solution therewith. This gas also reacts upon the sulphate of zinc (s. z.) which permeates the solution, and causes its zinc constituent to be deposited upon the copper. For these reasons it is necessary to dispose of the hydrogen in such a way that interfering actions may be avoided. This is effected in practice by immersing the copper and zinc in different solutions. 16. The Gravity Cell. — In the voltaic element which has been described and shown in Fig. 4, the two solutions are of un equal densities, so that one can be made to float, as it were, upon the other, in the same manner that oil floats upon water. Hence it has received the name of the gravity cell. 17. Specific Gravity. — The density or weight of a given bulk of any liquid compared with that of pure water is termed its specific gravity (s. g. ) The s. g. of a liquid is numerically expressed in decimals or mixed numbers, pure water being taken as the standard or unity. For example, the s. g. of water being i.oo, that of linseed oil is 0.93, while that of commercial sulphuric acid is 1.84, and of mercury 13.58. 18. The Hydrometer.— The s. g. of any liquid may be determined with sufficient accuracy for ordinary purposes by means of the hydrometer, shown in Fig. 5, which consists of a hollow glass float, weighted below with shot, and carrying a stem at the top provided with a graduated scale. When the hydrometer is made to float in any liquid, the division of the scale at the surface denotes its s. .4 * The arbitrary scale of the hydrometer commonly known as Baume's, is determined as follows : — The point to which the instrument sinks in pure water is assumed as o° (zero), while 15° is at the point to which it sinks in a solution containing 15 parts by weight of common salt in 85 parts of water. This space is divided into 15 equal parts, and equivalent graduations are continued to any desired extent. The most useful scale for testing the s. g. of battery solutions is one having a stem about 2 inches long, graduated in degrees from 15° to 40°. These degrees denote the percentage of common salt in a solution ; but do not correspond exactly with the percentages in battery solutions, as will appear from an examination of the tables in (23). is 7 in. high and 6 in. in diameter, is intended to contain 7 Ibs., or 0.84 U. S. gallons of liquid ; and this quantity, when the copper and zinc plates are in place, will fill it to within about one-half inch of the top. A smaller size of cell (6 in. x 5 in.), is also kept in stock by dealers. 20. To charge the cell, prepare separately a sufficient quantity of the zinc and of the copper solutions. For the zinc solution, which may be mixed in the jar, take for each cell : the solution should be i.io. 21. It is not absolutely necessary to make use of s. z. in setting up the cell. If pure water be substituted for the solution directed to be used in the last paragraph, and the circuit be closed between its poles, which is technically termed short-circuiting the cell (14), sufficient s. z. will be formed within a day or two to bring it into full action. Many electricians are of the opinion that a cell started in this way will remain in good condition for a longer time than if charged with a mechanically-mixed zinc solution. take in another glass vessel, for each cell : Pure soft water, by weight, 42 oz. (2^ pints). Crystallized sulphate of zinc, 4 oz. Crystallized sulphate of copper, 8 oz. Saturation. 24. Installation of the Gravity Cell. — The copper and zinc plates being put in their respective places in the jar (which will then 4>e about three-fourths full of s. z. solution), the heavier s. c. solution may be introduced into the bottom by means of a f in. tube of glass or rubber, having a small glass or rubber funnel inserted in its upper end. The lower end of the tube must be central and very near the bottom, and the s. c. must be poured in quite slowly, so as not to agitate the mass and cause the two solutions to mingle. If this operation is carefully performed, the lower part of the jar will now be filled with s. c. solution, of a uniform deep blue color, to a point a little above the top of the copper plate, being separated from the transparent s. z. solution above by a sharply defined line of demarkation. Care must now be taken that the cell is not moved about,, shaken, or stirred by the careless removal of the zinc or copper plates, as this would cause the two solutions to intermingle, a condition which it is very necessary to avoid. For the same reason, it is advisable to place each cell in the position which it is to permanently occupy, before introducing the s. c. solution. The most convenient place will be found to be a shelf about 48 in. from the floor. An enclosed box affixed to a wall or frame, and having a glass front hinged to open upward, is an excellent arrangement, as the cells are then in sight, so that their condition may be observed at all times, while at the same time they are protected from dirt,, and in a great measure from evaporation and from extremes of temperature.5 25. Instead of mixing the s. c. solution in a separate vessel, it is a common practice to fill the jar to within i inch of the top with the s. z. solution, prepared as above directed, and then slowly drop in 8 oz. of s. c. crystals about the size of a hazel-nut, which will fall tothe bottom and slowly dissolve. The only objection to this procedure is its liability to form a s. c. solution of unequal density in different parts, which is undesirable (26). When this plan is adopted, care must be taken not to put in more than the prescribed quantity of s. c., and particularly to see that no particle of it gets upon the zinc plate. tageous form for the copper plate than that which has been described, 6 Wooden, tin, or porcelain covers are sometimes fitted to the cells for excluding dust and preventing evaporation, and serve a good purpose. Wooden covers should not fit too closely ; there is danger that they may swell from moisture and fracture the jars. Great annoyance is sometimes caused by the apparently unaccountable breakage of glass jars. The primary cause of this is poor material or imperfect annealing during the process of manufacture ; the immediate cause is usually a sudden change of temperature. A jar on a high shelf in a warm room in winter is sometimes cracked by the current of cold air caused by opening an outer door. A little care will avoid such accidents. Formation of the Electric Circuit. 1 1 particularly in case it is desired to maintain a current of moderate quantity for a long time, is a ribbon of very thin rolled copper, 48 in. long and J in. wide, coiled spirally like a clock-spring, and laid flat in the bottom of the cell, the conducting wire being riveted to the outer end as seen in Fig. 6. An objection to the form of plate shown in Fig. 4, when used under the conditions here mentioned, is that unless carefully looked after, the s. c. solution will become weaker at the top than at the bottom of the copper, whereupon a closed circuit (30) is established, consisting of one FIG. 6. Modification of Copper metal (the copper), and two dissimilar liquids (the strong and the weak solution), setting up an action which is liable to attack and destroy the upper portion of the plate, uselessly consuming material for which no equivalent external current is rendered. 27. This action explains the necessity of enclosing the connecting wire from the copper electrode of the gravity battery in a glass tube, or covering it with gutta-percha or india-rubber, where it is exposed to the action of the solution. If it were not protected it would soon be destroyed by chemical action, and the circuit consequently interrupted. 28. Formation of the Electric Circuit.— The parts of the cell being properly assembled together, and the solutions in their respective places as directed in (24), the element is ready for service. If now the zinc and copper plates be joined together in the air by a metallic wire as before explained (14), a current of electricity, as it is technically termed, will traverse the wire. It wilt traverse, moreover, not only the wire, but also the metallic plates and solutions within the voltaic element, the whole path forming what is termed a circuit of electrical conductors, or briefly, an electric circuit. 29. The presence of an electric current in such a circuit may be demonstrated in several different ways, as will be shown further on (86). For the present we are only concerned to observe its immediate effects upon the constituent parts of the voltaic element which sets it in action. FIG. 7. Diagram of Closed Voltaic Circuit plate is termed the positive plate or element, and the copper the negative plate or element. These terms are purely conventional and arbitrary, and properly signify nothing beyond the antagonistic or opposite electrical condition which exists. The general term for these plates is electrodes, a term introduced by Faraday. The air terminals of the electrodes, to which the conducting wires are attached, are called the poles. It should be noted that the copper plate of the element, although the negative electrode, is connected with the positive pole, and in like manner the zinc or positive electrode is connected with the negative pole, because the current is conventionally assumed to flow from the positive plate, through the solution and out by the copper plate. The positive and negative poles of every generator of electricity are respectively designated by the conventional signs -f- and — (plus and minus). The direction of the electric current, for convenience of description, is conventionally assumed, as above stated, to be through the solutions from the zinc to the copper electrode, and thence through the connecting wire from the copper to the zinc electrode. The assumed direction in any wire is denoted by the conventional sign of an arrow pointing in the direction of the negative pole. 32. Chemical Reactions Arising in the Closed Circuit. — The chemical reactions within the cell, when its external circuit is closed, and its several constituent parts traversed by an electric current, are as follows : particle with the metal of the zinc plate, forming oxide of zinc. (2.) The oxide of zinc, formed as above, combines with the sulphuric acid of the s. z. solution (14), and forms s. z., which is added to the s. z. already present in the solution surrounding the zinc. deposited in a pure metallic form upon the copper plate. At the surface of the zinc plate, the oxygen of the water contained in the s. z. solution is separated from the hydrogen, while at the surface of the copper plate this hydrogen combines with the oxygen which is separated from the oxide of copper. 33. Effect of Continued Action. — This action goes on without cessation, provided the circuit remains closed, until some one of the materials contained in the cell becomes exhausted. It will be observed that as the action continues, the zinc plate is gradually dissolved, being oxidized, or in fact burned ; that the proportion of sulphate in the s. z. solution constantly increases, rendering it more dense and its s. g. greater ; that, on the contrary, the s. c. solution grows less dense, and its s.g. diminishes ; and finally, that the copper plate continually increases in weight, by the deposition upon its surface of metallic copper abstracted from the copper solution in which it is immersed. 34. As the weight of the s. z. solution, as indicated by its s.g., gradually .increases, while on the contrary that of the s. c. solution continually becomes less, it necessarily happens after the lapse of a greater or less time, the former becomes heaviest, and consequently descends to the bottom of the cell, forcing the s. c. solution to the top, where it is brought into direct contact with the zinc plate, depositing metallic copper thereon. This deposit interrupts the normal chemical action of the cell to such an extent that the electric current greatly diminishes, and ultimately ceases altogether. 35. By intelligent management this injurious action may be prevented, or at least postponed for a long time. The frequent use of the hydrometer .(18) is almost indispensable for this work, and a knowledge of the condition of the cell is also greatly facilitated by placing it in front of a window, so that its interior may be clearly viewed by transmitted light ; or at all events, it should be provided, if possible, with a white background. 36. Rate of Consumption of Material. — The rapidity with which the materials of the cell are consumed, and its active life shortened, depends almost entirely upon the amount of work done by it, or in other words, the quantity of electricity per unit of time which it is required to furnish. This question, which is an exceedingly important one, will be fully considered further on (154). 37. Maintenance of the Cell. — The first sign of the exhaustion of a cell generally appears in the s. c. solution. It is not practicable to examine the condition of this solution by means of the hydrometer, but fortunately the degree of intensity of its blue color furnishes an infallible indication of its density. The strong blue tint of the original solution will after a time begin to fade in the vicinity of the upper edge of the copper plate, and the line of demarkation between it and the zinc solution will become less and less distinct. When this is seen to occur, additional s. c. must be supplied, either through the tube in the form of a solution as directed heretofore (24), or by dropping i oz. of crystals into the jar, being careful to observe the precautions heretofore noted (25). It is much better not to make use of finely powdered s. c. for this purpose, as this is liable to cement itself into a hard insoluble mass at the bottom of the cell, which defies all efforts to remove it without breaking the jar. The s. z. solution should be tested by means of the hydrometer (18) at least once a week while the cell is in constant action. The s. g. of the solution, which at the outset was about i.io, will gradually increase. When it reaches 1.15, as shown by the scale,, the solution should be diluted with water. If the s. z. solution be permitted to approach closely to its saturation point, 1.45, see table (23), not only is the chemical action of the cell diminished, but a saline deposit of white powder (crystallized sulphate of zinc) begins to form upon the zinc, and upon the edge of the jar above the solution, and by capillary attraction ultimately conveys the liquid over the edge to the outside of the cell and creates a disagreeable nuisance. This may be avoided by keeping the s. g. of the zinc solution below 1.20 and by occasionally wiping the inner edges of the jar with a cloth or sponge saturated with cotton-seed or heavy paraffin oil. 38. Prevention of Evaporation. — Sometimes a thin stratum of one of the oils above mentioned is gently poured upon the top of the zinc solution, after the cell has been set up as directed in (24), a procedure which effectually prevents evaporation and the formation of saline salts. Inasmuch, however, as the presence of the oil renders the cleaning of the zinc plate, when necessary, a disagreeable and inconvenient task, it is perhaps an open question whether the practice is to be recommended. If it is at all possible to give the cell proper attention from time to time as required, it is probably better to dispense with all such expedients, but when such is not them. 6 39. The best way to dilute the zinc solution is to use a tube of rubber, glass, or lead, about 24 in. long, and -J- in. diameter, bent into a siphon, or an inverted \|\|, one leg of which is considerably longer than the other. Fill the siphon with water, stopping both ends with the ringers, and after placing a wooden bucket or other convenient receptacle in front of the cell, but at a considerable lower level, dexterously insert the tube into the cell (at the same time removing one finger), so that the inserted end will be near the center of the jar and about \|- in. above the copper plate, while the longer end is directed toward the bucket. Now withdraw the other finsrer small sprinkling pot having a fine rose at the end of its spout, or with due care, may be equally well effected by holding a spoon or some such implement just at the surface, so as to break and scatter the vertical force of the stream as it is poured. 6 Another device which is sometimes resorted to for the purpose of preventing the formation of salts upon the edge of the jar, is to invert the latter before using, and dip it in a bath of melted paraffin contained in a shallow dish, to the depth of half an inch or less, which forms, when cold, an adherent and repellent coating. 40. Dismantling the Cell.— The above described operation, if properly carried out, will practically restore the cell to its original working condition. The increasing deposit upon the copper plate will not interfere with the proper action of the cell, and need not be disturbed. The zinc plate, however, will gradually become covered with a thick coating of dark brown oxide, which will adhere to it with considerable tenacity. This must be removed from time to time, especially when, by becoming of a reddish color, it shows traces of deposited copper. Lift the zinc plate carefully from the solution, and remove the crust which has formed upon the metal, by means of a scraper of hard wood, or a stiff brush sold by dealers in supplies for that purpose (a wire brush answers the purpose admirably). Remove all the oxide clown to the surface of the metal, wash the latter in clean water, and return to its place in the cell. If any undissolved crystals of s. c. are found in the bottom of the jar, these should be washed and used again. The zinc should be cleaned 'at once after removal from the cell, while still wet. If the cleaning has to be deferred, the zinc must be placed in water for some time before commencing operations. Great care must be taken to see that no water gets between the arm of the zinc and the brass binding-screw, as this will cause a deposit of sulphate of zinc, which may entirely prevent the passage of the current when the zinc is again put to use. 41. Diffusion of Solution within the Cell. — An absolute separation of the copper and zinc solutions in the voltaic cell cannot be attained. Liquids of unlike density separated from each other by gravity always tend to intermingle by a slow process of diffusion, and thus ultimately to form one homogeneous solution. This tendency may be reduced to a minimum by intelligent management and proper attention to the requirements of the cell while in action, so as to cause but little practical inconvenience. 42. The solutions manifest a much stronger tendency to mix when the cell is on open than when on closed circuit. Hence, cells in which the solutions are separated by gravity, and in fact all sulphate of copper cells, give the most satisfactory results when used, as in telegraphy, upon circuits which are closed the greater portion of the time. 43- Neutralizing the Zinc Solution. — When the cell is dismounted and renewed, the s. z. should be drawn off with the siphon and thrown into a wooden vessel, together with a few pieces of metallic zinc, which will purify the liquid by reducing any metallic copper which may be present in it. It should then be filtered or Waste Products of the Cell. 1 7 strained through cloth or sand, and afterward diluted with water until its specific gravity is reduced to i.io. It is then in suitable condition to be used in the renewed cell, instead of making a new solution as directed in (20). 44. Waste Products of the Cell.— Where a large number of cells are in constant use, it is generally worth while to dry and preserve the material thus removed from the zincs, commonly called "battery mud," as it is rich in metallic zinc and copper, and will usually be willingly purchased at a fair price by brass-founders. When the copper plates have become heavily encrusted with metallic deposits, they may with advantage be disposed of in the same way. Electrotype or deposited copper, as this is termed, is much valued in many of the industrial arts. 45. Copper plates which have been used in the battery, and which are intended to be used again, should be kept in water; taking care that the connecting wire, with its coating of gutta-percha or indiarubber, is completely immersed. Zinc plates, on the contrary, must be kept in a dry place, never in water. 46. Other Forms of the Cell. — Much unprofitable ingenuity has been displayed by inventors in varying the form, proportions and relations of the elements of the sulphate-of-copper cell, in pursuit of imaginary advantages. As a matter of fact, it has been found to be almost wholly immaterial what the form and arrangement of the parts may be, so long as the necessary general principles of action are kept in view. The consumption of a given amount of zinc and sulphate of copper can never in any chemical combination, or under any circumstances, evolve more than a definite and perfectly well ascertained quantity of electricity, in a form available for use, although if the cell be unskillfully proportioned or arranged, the quantity of electricity evolved may be less than it should be (154). The principal difference between different forms is that some require less frequent attention than others ; but this advantage is sometimes gained at the expense of other more valuable qualities. 47. Among the different practical voltaic cells which have been employed in America to a greater or less extent, commonly known by the names of their originators and designers, but involving essentially the same principles as the one which has been described, may be mentioned the Hill,7 Callaud,8 Minotto,9 Thom- be had to the publications indicated in the references. 48. The Lockwood Cell.— This form of cell has been found to give excellent results in cases in which a moderate but perfectly uniform current is required without attention for a great length of time. The jar is of extra depth (9 in.) and the copper plate consists of two flat spirals of wire coiled like a clock-bell and laid in reverse directions to each other, one beneath and the other at the top of a mass of 5 Ibs. of s. c. in crystals, placed in the bottom of the jar. The connecting wire is continuous with the lower spiral, while the two spirals are united by a vertical rod or stout wire which is connected to their inner ends. The action of the current traversing the coils appears to act, in some manner not well ascertained, to oppose the tendency of the s. c. solution to ascend in the jar and reach the zinc plate. A series of these cells will maintain a current for a year under favorable conditions. 49- The Daniell Cell.— This is the original form of the sulphate of copper element. It was formerly much used in the telegraphic service, but has now been practically superseded by the equally efficient and more economical gravity cell. As usually constructed, the Daniell cell consists of a jar of glass or earthenware F (Fig. 9) 6 in. in diameter and 8 in. high. A thin sheet of copper G is bent into a cylindrical form so as to fit loosely within the jar, and to this is affixed a chamber provided with a perforated bottom, designed to receive a supply of s. c. in crystals. A copper strip is riveted to the plate G and provided with a clamp at its extremity, adapted either to receive a conducting wire, or to connect to the zinc plate of the next adjacent element, as the case may be. Within the copper cylinder is a porous-cup (as it is technically termed), H, of unglazed porcelain ware, 7 in. high and 2 in. diameter, within which is placed a bar of cast zinc of the cross-section shown at X, or as sometimes preferred, a hollow cylinder with a vertical slit in one side, the latter form yielding a somewhat greater quantity of electricity, but being less convenient to clean. 50. The porous-cup H is filled with s. z. solution prepared as directed in (20) and the jar outside the porous-cup with s. c. solution of s. g. 1. 10. A quantity of the crystals may be placed in the perforated chamber attached to the copper plate, which gradually dissolve and thus maintain the solution at its proper density. Pure water may be used in the porous cell as directed in (21) if preferred. Maintenance of the Daniell Cell. 51. Maintenance of the Daniell Cell. — This cell is maintained in substantially the same manner as the gravity. Unless a very large volume of current is required, it will be found much more FIG. 9. The Daniell Cell. economical to feed the s. c. solution with small quantities of crystals, placed in the chamber once in every two or three days, and keeping the solution but half saturated (s. g. i.io) and uniform in color throughout, by stirring it with a wooden or glass rod. The s. z. solution should be maintained as nearly as possible at the same s. g. as the copper solution. 52. Renewal of the Daniell Cell.— When taken apart for cleaning, more or less copper will usually be found deposited in patches on the porous-cup. This deposit cannot be prevented, but may be greatly diminished by suspending the zinc free from the bottom or sides of the porous-cup, or even by placing a piece of glass in the bottom of the cup for the zinc to stand on. It is also a good plan, for the same reason, to saturate the bottom of the porous-cup to the height of half an inch with melted paraffin or tallow before putting it to use. The porous-cup ought to be replaced by a new one whenever as much as half of its surface has become encrusted with metallic copper by continued use. If it becomes cracked it should be replaced at once, or a great waste of material will ensue. The porous-cup of an element intended only for occasional use, may with advantage be made thicker and less porous in texture than if intended to be kept continuously in action. 53. Intermingling of the Solutions.— It should be observed that at the best, a porous cell merely obstructs and does not prevent the ultimate intermingling of the copper and zinc solutions. The liquids will pass through the porous wall of the cup by virtue of a singular property, common to all dissimilar liquids when separated by a porous partition,11 and will be found to exhibit a constant tendency to rise in the outer cell and to disappear from the porouscup. This tendency is obviously assisted by the passage of the current. 54. Porous-cups which have been used in a cell, must not be allowed to become dry after being taken out, but should be kept in water, otherwise the crystallization of the s. z. contained in the pores will almost certainly break them. 55. Choice of Battery Materials. — The s. c. and the metallic zinc used for electrical purposes should be of good quality and free from adulterations. Adulterated s. c. is very seldom met with in the United States ; that sold by dealers in electrical supplies is almost uniformly of good quality. The best commercial zinc usually contains a small proportion of iron and lead. An analysis of spelter of good quality for electrical purposes, gave : Iron 0.06 56. The question of the effects of temperature upon the efficiency of the voltaic cell is a very important one, and merits much more consideration than it has hitherto received. The sulphate of copper cell is especially sensitive in this particular, and should be carefully guarded against cold. This subject is further considered in a subsequent chapter (162). (4.) Keep the s. c, solution of a strong blue color up to a point just above the copper plate, by adding s. c. as fast as it is consumed by the action of the current, but be careful never to put in too much s. c. at one time. upon the edges of the jars. (7.) Do not let the zinc become too heavily coated with brown oxides. If the oxides tend to form into pendants, hanging below the zinc, detach these at once with a bent wire ; they cause a great waste of material. (8.) It is an excellent plan to wrap the zinc neatly in linen paper (the kind called parchment paper is best), securing the folded flaps at the top with sealing-wax, and tying strongly with twine passed several times around the whole. This expedient prevents particles of zinc from falling on the copper, and also aids the action of gravity in preventing the too rapid upward diffusion of the s. c. solution. 58. The Oxide of Copper Cell. —A voltaic combination in which the metallic elements are amalgamated zinc 12 and protoxide of copper (Cu O),13 and the exciting agent a solution of caustic potash ( K O ), has of late found much favor in the telegraphic service, under the name of the Edison-Lalande cell. In the size designed for this use, the glass contain ing-jar is 8 in. high, 6 in. in diameter, and Lalande Cell. 12 Zinc which has been immersed in dilute sulphuric acid, and then coated with mercury, is said to be amalgamated. This process renders the chemical action upon the zinc more uniform and less wasteful in certain forms of voltaic elements. It is of no advantage in the sulphate of copper element. weighs 5.75 Ibs. It is provided with a porcelain cover, from which are suspended two rectangular plates of rolled zinc, fitted with a double clamp-screw for attaching the wire. A skeleton frame of copper (Fig. 10) is fitted to clasp two rectangular slabs containing i Ib. of copper oxide, and is suspended from the porcelain cover between and facing the zinc plates. To prevent possible contact, a fender of hard rubber is inserted between the oxide plates, projecting on each side. A transverse copper bolt and nut clamps the whole firmly together. Fig. n shows Cell. — The solution for this cell consists of i part by weight of caustic potash dissolved in 3 parts pure soft water (s. g. 1.33 ; 38° Baume), with which the jar is to be filled to within i in. of the top. Caustic potash, in sticks of a size just sufficient to make the proper solution, are usually supplied by dealers. The solution should be stirred with a wooden or glass rod while the potash is dissolving, otherwise the evolution of heat may fracture the jar. Finally, a stratum of heavy paraffin oil (s. g. 1.46 ; 48° Baume), about J in. deep, is poured upon the solution to prevent evaporation. The cell will ordinarily require no further attention until its materials are entirely consumed, when both the zinc and oxide plates, as well as the solution, must be renewed. 60. Chemical Reactions of the Oxide of Copper Cell.— When the external circuit is closed, the oxygen of the water in the solution, uniting with the zinc, forms oxide of zinc as in other cells. This, combining with the potash in the solution, forms a soluble double salt of zincate of potash, which is decomposed as rapidly as it is formed. The hydrogen which is set free unites with the oxygen of the protoxide of copper of the negative plate, and deposits metallic copper. The reaction takes up i equivalent of zinc, i of potash, i of protoxide of copper, and deposits i equivalent of metallic copper. The wasteful local action in this cell is so small as to be practically zinc electrode which has to be thrown aside, sometimes amounts to 45 per cent, of the original weight. This loss is avoided by the " wasteless " electrode invented by G. dTnfreville, which is made up of two or more similar sections^ each formed of a hub with inclined radial arms (see Fig. n#.) The hubs of the several sections are slightly coned, and fit snugly into one another. Fig. \\b. shows an electrode of three sections after having been some time 62. Magneto-Electricity. — Electricity which is evolved from a magnet, by moving coils of wire within the sphere of its influence by mechanical power, is called magneto or dynamo-electricity. The distinction between the two is purely arbitrary and nominal, and has reference only to the particular structure and organization of the machines from which they are respectively derived. 63. Magnetism. — It has been known from time immemorial that certain natural ores of iron possessed the property of attracting iron and steel, and that these metals were themselves capable, under proper conditions, of being endowed with a like property. This property, which is called magnetism, is also capable of being manifested, though in a less marked degree, by certain other metals, especially cobalt and nickel. Such a mass of magnetic ore is called a natural magnet or lodestone. A mass of iron or steel to which magnetic properties have been imparted by any known means, is called an artificial magnet. Soft iron is capable of retaining magnetic properties only during such time as it remains under the direct influence of the magnetizing force, and under such conditions is said to be a temporary magnet. Hardened iron or steel continues to retain magnetic properties after the withdrawal of the magnetizing force ; and hence a mass of hardened steel, when magnetized, is called a permanent magnet.1 64. The Magnetic Needle. — A piece of hardened steel, which has been permanently magnetized, possesses marked peculiarities. When a straight bar of this kind, which is termed a bar-magnet, is suspended freely by its center of gravity, it always tends to place itself approximately north and south, usually in the direction of its greatest length. The imaginary line in which it thus places itself is termed the magnetic meridian. A small magnetic steel bar, when 1 For an exposition of the modern theories of magnetism, the student is referred to the papers of D. E. Hughes, Proc. Royal Soc., 1879, p. 56; J. A. Ewing, Royal Soc., 1890; Elec. World, xvi. 241. A summary will be found in Kapp, Electric Transmission of Energy, 16. The celebrated lecture of Prof. A. M. Mayer, The Earth a Great Magnet, New Haven, 1872, presents the whole subject of magnetism in a most admirable, popular way. Phenomena of Magnetic Induction. suspended by a filament, as shown in Fig. 12, or upon a pivot, as shown in Fig. 13, is called a magnetic needle. Such a needle, in conjunction with a graduated dial, constitutes the well-known magnetic compass. 65. Phenomena of Magnetic Induction. — When an artificial magnet is placed in the immediate neighborhood of one or more pieces of iron, or of a quantity of iron chips or filings, these are instantly at- tracted. They attach themselves to the magnet, and will be found to adhere with considerable force to its surface. At the same time, a magnetic influence is exerted upon these bodies by virtue of which they themselves become magnets. The magnetism thus appearing in such bodies is said to be induced \\\ them, and this process of imparting or developing magnetism is called magnetic induction. Thus, in Fig. 14, NS is a bar-magnet, k is an iron key which is attracted and held suspended by it, and ;/ is an iron nail, in turn held in the same way by the key, which has itself become a magnet. The FIG. 14. Attraction of Magnet. quantity near each of the ends than toward the middle of the bar, as shown in Fig. 15. This shows that the attractive force of a magnet is at its maximum at two points situated near the respective ends of the bar, and gradually diminishes toward the center, where it disappears altogether. These two points of maximum attraction are termed the poles of the magnet. The one polar magnets, have more than one set of poles. The distance between the poles of a magnet is called its magnetic length. In most bar-magnets it is about 0.83 of the total length. In a horseshoe magnet (67) it is the shortest distance between the poles. A magnet need not necessarily be magnetized in the direction of its greatest length ; a bar may be magnetized transversely, or in fact in any direction. When a magnet is broken into detached parts, each fragment instantly becomes an independent magnet, having a north and south pole. 67. Horseshoe Magnet and Armature1.— Instead of being straight, as in Fig. 14, it is more usual, as well as more convenient, for the magnetic bar to be given a form resembling the letter U» as m Fig. 16. This form is known as the horseshoe magnet. A soft iron armature is usually fitted to the poles of a horseshoe magnet. This is sometimes called the keeper, because it aids in retaining or keeping the magnetic qualities of the bar. In general terms, any mass of iron or steel subjected to the attraction of a magnet is considered to be an armature. A magnetic attraction has been experimentally produced between a magnet and its armature as high as i. ooo Ibs. per sq. in. of surface in contact.3 2 The north pole of a magnetic bar or needle, by convention, is usually painted blue> and the south pole red. Sometimes they are respectively stamped with the letters N and S, and sometimes a straight line or mark serves to designate the north pole. by its effects upon matter. Since the peculiarities of the magnetic field are due to the presence of a force, the properties of such a field may be made known by determining the strength and the direction of this force, or, as it is usually expressed, the intensity of the field, and the direction of the lines of force* 70. Lines of Magnetic Force. — The invisible lines of mag netic force radiate in every direction from each pole of the magnet. They may be regarded as an inseparable part of it, which accompany it wherever it goes. Perhaps their true nature may be more clearly pole, and after curving for a greater or less distance through space, to return again to the south pole, as indicated by the arrows in Fig. 19. A view of the spectrum of the magnetic field at one pole of a bar-magnet, as seen by a field filled with invisible lines of force which we term magnetic meridians. These lines determine the position of the suspended magnetic needle. Thus by exploring with such a needle, the direction of the lines of force in any magnetic field may be discovered (94). compression, cohesion, adhesion, resistance, inertia, strain, stress, strength, thrust, load, squeeze, pull, push, etc., all of which can be measured or expressed by weight, without regard to motion, time, power or work.— J. W. NYSTROM : Elements of Mechanics, p. 59. ent magnets mutually attract each other. Hence it follows that the north pole of any magnet must have the same polarity as the south pole of the earth, and in strictness ought to be termed the south pole rather than the north (66). It is more properly termed the north-seeking pole. of force passing through it, a current of electricity will appear in the wire. The same thing will occur if the wire be stationary and the field be moved ; or if the wire be stationary and the intensity or strength of the field be increased or diminished, either between zero and maximum, or to a lesser extent ; or if the wire be moved from one part of the field to another part of different intensity.5 74- Thus in Fig. 22,6 let the parallel arrows be assumed to represent lines of 'force in a uniform magnetic field. If the closed ring of wire be moved parallel to those lines, as indicated by the dotted other hand, represents a field which is not uniform, being stronger or more intense, or in other words, having a greater number of lines of force, in some parts than in others. Moreover, as shown by the arrow-heads, these lines similar in kind, but will be even greater in amount. So, also, if the ring be moved in a uniform field in such a manner that either the number or the direction, or both, of the lines of force cut by it are varied, a current will be produced. This happens if the ring be turned round an axis at right angles to the direction of the lines of force, as shown in Fig. 25. achieved by man, with the possible exception of the discovery of the expansive power of steam— is given in his Experimental Researches, i. 7. See N. Y. Elect. Eng. , xiii. 27. • SILVANUS P. THOMPSON : Dynamo-Electric Machinery (2nd edition;, 12. motion. The equivalent of mechanical energy thus consumed reappears as electricity in the closed ring, except that a certain portion, which is transformed into heat, as will be hereafter more fully explained (87). 76. Direction of the Induced Current. — It has been stated (31), that what we call the direction of a voltaic current is conventionally assumed to be from the positive pole of the cell through the conducting wire to the negative pole ; and it will be obvious that if the respective poles were interchanged, the current would traverse the wire in the opposite direction. The direction of the current produced in a conductor by moving it with reference to the lines in a field of force, called the magneto-electric current, depends upon the direction in which the relative motion takes place. The law may be stated as follows : A decrease in the number of lines of force which pass through or are cut by a closed circuit, produces a current round that circuit in the positive direction ; while an increase in the number of lines of force which pass through or are cut by such circuit, produces a current around such circuit in the negative direction.8 The positive direction of the lines of magnetic force which pass through the loop of the circuit, is invariably associated with a positive direction of the current flowing round the conducting circuit, 7 This and the four following paragraphs explanatory of the mutual reactions of the magnet, the magnetic field and the conductor, are abridged from a portion of chapters ii. and iii. of SILVANUS P. THOMPSON'S admirable work on Dynamo- Electric Machinery. just as the forward thrust is with the right-handed rotation in the operation of driving an ordinary right-handed screw. This will appear from an examination of the direction of the current in the 'ring as shown by the arrows in Fig. 25. 77. Mutual Reactions of a Current and a Magnet.— The phenomena which have been described, like most physical phenomena, are reversible; that is to say, a magnetic field may also be created by the passage of an electric current through a wire conductor, and, moreover, a mass of iron or steel situated in such a field will become magnetic. This effect, which is called electro-magnetism (86, </), lies at the foundation of electric telegraphy. magnet. (ii.) The establishment and maintenance of a continuous electric current in a conductor requires a continuous expenditure of energy, or, in other words, consumption of power, in order to produce the necessary motion. (iii.) To induce currents in a conductor, there must be relative motion between conductor and magnet, of such kind as to alter in some manner the number of lines of force cut transversely by the conductor. more powerful will be the current. (vi.) The direction of the induced current depends upon the direction of the motion of the wire with reference to the direction of the lines of force in the field. 79. The Dynamo-Electric Machine. — A dynamo-electric machine, briefly termed a dynamo, in the general and most proper sense of the term, embraces every machine capable of converting the energy of mechanical motion into the energy of an electric current, and it is in this sense that the term dynamo will hereafter be used in this treatise. 80. The Theoretical Dynamo. — The simplest conceivable dynamo is illustrated in Fig. 26. It consists of a single rectangular loop of wire, rotating in a uniform magnetic field maintained between Frictiona I Electricity. the north and south poles of a large horseshoe magnet. If the loop be first placed in* a vertical plane, as in the figure, the number of lines of force passing through it will be a maximum, but as it is turned by the crank into a horizontal position, the number of intersecting lines will obviously diminish to zero. On continuing the rotation beyond this point, the lines begin again to thread through the loop from the opposite side, so that there will be a negative or reverse maximum when the loop has been turned through an angle of 180", or half-way round. During the first half of the revolution, therefore, a current will be induced in the loop in one direction, the strength of which will increase gradually from zero to maximum and then diminish again to zero. Upon passing the 180° position,, there will begin an induction in the reverse sense, and a similar effect will again take place, resulting in the induction of a current in the loop in the opposite direction, the operation being completed when the loop has been carried through one complete revolution. 81. Further considerations, having reference to the construction and mode of operation of the actual dynamo, may profitably be postponed until the student has become familiar with the fundamental laws which govern the flow and distribution of electric currents, as the reaction of these currents upon the machine which produces them, though important, are somewhat complex, and in the absence of such knowledge will be found difficult of comprehension (299). 82. Frictional Electricity.— Frictional electricity, which is one form of what is termed static electricity, finds no practical application in telegraphy. Nevertheless, the phenomena of static electricity, under certain conditions, manifest themselves in such a way as to interfere with the transmission and reception of telegraphic signals, and hence it will become necessary, in connection with that subject, to give the matter further consideration. (See Chapter VIII., § 314.) 83. Thermo-Electricity.— This name has been given to electricity derived from the direct conversion of heat-energy. Its application to telegraphy has thus far been purely tentative, and does not require consideration here.9 MEASUREMENT. 85. The Electric Current. — It has been stated (28) that a conducting wire uniting opposite poles of what, for convenience, we call a generator of electricity, whether this be a voltaic cell (30) or a magneto-electric apparatus (80), is endowed with certain peculiar properties, by reason of which we conventionally assume an electric current to flow from the positive to the negative pole of such generator. 86. Manifestations of the Current. — The existence of this so-called electric current in the conjunctive wire is manifested in several different ways, the most important of which are as follows: (a) If the wire be dipped in iron tilings, a mass of these will cluster around it and apparently adhere to it, appearing as in Fig. 27. (fi) If the wire be placed in the immediate vicinity of a freely suspended magnetic needle (64), the latter will immediately tend to set itself at right-angles thereto, as indicated in Fig. 28. Moreover, the direction in which the needle moves will indicate the direction of the current (31). (r) If the wire be placed parallel to another wire, or to another portion of the same wire which is also conveying an electric current, repulsion or attraction will be manifested between the two wires according as the two currents flow in the same or in opposite directions. (e) If the wire be severed and its ends immersed in water, the water will be decomposed, the oxygen appearing at one terminal and the hydrogen at the other, as shown in Fig. 30. This action is termed electrolysis. (/) If the severed ends of the wire be united by a very thin wire of platinum, 3 in. or 4 in. long, and this be placed in a vessel of alcohol, a thermometer will show the liquid to become heated by the action of the current upon the wire (see Fig. 31). (g) If the ends of the severed wire be placed side by side upon the tongue, a peculiar taste will be experienced; and if the current be strong enough, it may be felt by the fingers. This sensation is termed an electric shock. Absolute System of Measurement. 37 absolute measurement of electricity and magnetism is, as Thomson remarks, " merely an extension of the astronomer's method of reckoning mass in terms of what we may call the universal gravitation unit of matter, and of the reckoning of force adopted by astronomers, in common with all workers in mathematical dynamics, according to which the unit of force is that force which, acting on a unit of mass for a unit of time, generates a velocity equal to the unit of velocity* 89. Illustration of the Absolute System of Measurement.— As a concrete example, suppose we take a pound weight as our unit of mass, and allow it to drop through space for a period of one second, our unit of time. This mass will always fall through the same space during the unit of time, and at the end of that time will be capable of striking with a certain determinate force, which is obviously measurable by an equivalent weight, and which therefore becomes our unit of force, while the distance through which the mass falls in one second becomes our unit of spaced Such a system of measurement being wholly independent of the physical properties of any arbitrary material, is properly called an absolute system. 90. Derivation of Electrical and Magnetic Units. — The actual units used in the measurement of electricity and magnetism, are founded upon the French or metric system of weights and measures, which has been commercially, adopted by all the civilized countries of the world except Great Britain and the United States, and is in extensive use in the last named countries among scientific men. In electro-magnetic measurement, therefore, the centimetre has been adopted as the unit of space, thegrtm the unit of mass or weight, and the mean solar second the unit of time. This is briefly denominated the e.g. s. (centimetre-gram-second) system.4 91. The C. G. S. Units of Force and Work.— The act of moving a weight of i gram through a space of i centimetre, during the time of i second, requires a perfectly definite and measurable * The units of space, mass, and time, have been selected by common consent to ierve as fundamental units. Other units, for practical use, determined from these, such for example as the unit of force, are termed derived units. 3 In making this general statement, the effect of the resistance offered by the air has been neglected (this being, of course, greater for a less dense than for a more dense body), as has also the fact that a given mass which weighs a pound, for example at Washington, D. C., will weigh more than a pound at the north or south pole of the earth, and less than a pound at Panama, or at the equator. This is due to the fact that the earth is not a perfect sphere. « The centimetre is somewhat less than half an inch English measure ; i foot is very nearly 30.5 centimetres ; i cubic centimetre of water weighs i gram ; i oz. is very nearly 28 grams ; i Ib. is 454 grams ; the 5-cent nickel of the 1873 U. S. coinage weighs exactly 5 grams and has a diameter of 2 centimetres ; the silver dime weighs 2.5 grams. amount of force, which is termed a dyne. The dyne, therefore, is the unit of force in the c. g. s. system, and is defined as the force, which acting upon a gram for a second, generates a velocity of a centimetre per seconds Any force may be stated to be equal to so many dynes. A megadyne is equal to 1,000,000 dynes (123, note). Now if a force of i dyne be applied to move a closed conducting ring a distance of i centimetre through a uniform magnetic field (as, for example, the magnetic field of the earth), in the manner explained in (73), work is done; an electrical force is set up in that conductor which would be the exact electrical equivalent of the mechanical force of i dyne, were it not that some part of the original force is unavoidably transformed into heat during the operation. Neglecting the value of the heat-loss, this quantity of electricity is capable of doing mechanical work equal to i erg, as, for instance, by forcibly deflecting a magnetic needle (86, b) or by attracting the armature of a magnet (86, d). 92. The Conservation of Force. — This is one illustration of the great principle of the indestructibility or, as it is commonly called, the conservation of force? which is so important, that it has been justly remarked that the whole of natural philosophy is merely a commentary upon it.8 It follows from this principle, that whenever a signal is produced at any point by electrical action, a physical effect must be made to take place, and this necessarily involves the expenditure of some form of force at some other point. It may be the force of chemical affinity in the voltaic cell ; or it may be the force of steam or of falling water, or of human muscles exerted upon a dynamo-electric 7 DANIELL : Principles of Physics, 7. 8 This doctrine teaches that the total amount of force in the universe is unalterable, and that it can neither be created nor destroyed. Force, however, may appear in a variety of different forms, and is capable of being readily changed from one form to another, but every such mutation is nevertheless rigidly subject to quantitative laws. A given amount of one form of force produces a definite quantity of one or more other forms of force and no more. Hence this law is sometimes called the equivalence of forces. This important and interesting subject is well worthy of further study, and among special works relating to its various aspects, the author ventures to specially commend the following : — TYNDALL : Heat as a Mode of Motion ; YOUMANS : The Correlation and Conservation of Forces ; a collection of papers by Grove, Helmholtz, Mayer, Faraday, and others; STEWART: On the Conservation of Energy ; and SPE AGUE : Electricity, its Theory, Sources, and Applications. Electric Field of Force. machine, but in every case, the force expended must be equal to that which is utilized, plus that which is transformed into heat in the course of the operation. Telegraphic signals are usually produced by means of the attraction of an armature by an electro-magnet. The initiation and maintenance of this attraction involves the consumption in the battery of a perfectly definite and well ascertained quantity of material, which can never be less than the full equivalent of the mechanical work done, but must be somewhat more, and may possibly be very much more, for by unskillful arrangements an undue proportion of the original force may be turned into heat and rendered unavailable for the purpose in hand (154). 93. Electric Field of Force.— If we take a magnetic needle, which, as we have seen, tends to remain in the magnetic meridian, and place parallel to it a wire, traversed, as shown in Fig. 28, by a current in the direction of the arrows, the needle will seek to place itself at right-angles to the wire (86, b\ but being under the influence of two antagonistic forces, it will come finally to rest in an intermediate position. This experiment shows that a conductor, when con- FIG. 32. Spectrum of Field Surrounding Conductor. veying a current, is surrounded by a field-of-force of the same character as that which we have found to surround the magnet (69). To determine the position and direction of the lines of force in this field, we may adopt the same expedient as in the case of the magnet. Pass the conducting wire at right-angles through a piece of glass or card-board. If iron-filings be dusted into the field, they will arrange themselves in concentric circles (Fig. 32), showing that the .lines of force encircle the wire, instead of radiating outwardly from it as they did in the case of the magnet. It is these lines of force which act upon the needle and tend to set it at right-angles to the wire, for when any concentric line passes through both poles of the needle, the latter must set itself at right-angles to the radii of the circle (71). 94. Relation of Current Force to Mechanical Force. — The particular angular position of a needle under the influence of a current must necessarily depend upon the ratio between the strength of the magnetic field-of- force due to the current, and that of the field-of-force due to the magnetism of the earth, which may be regarded as sensibly constant in any particular locality. That portion of the force of the earth's magnetism which acts to hold a horizontal needle in the meridian is called its horizontal component (H). Its value varies from a maximum at the magnetic equator to nothing at the magnetic poles. Its locality of greatest intensity is in lat. o° and long. 101° W., where it is equal to 0.3733 dynes. Following are some determinations of its value by observers of the U. S. Coast and Geodetic Survey: (Rep't U. S. C. & G. S., 1885 ; App. No. 6.) This report gives the value of the horizontal intensity found in over 1,500 observations in various parts of North America, reduced to the epoch of 1885. The value of the horizontal intensity is subject in most places to a slow annual variation. Along a line drawn from British Columbia to Florida, the intensity is constant ; east of this line it shows an annual increase, and west of the line an annual decrease. {Rep. U. S. C. &* G. S., 1885, p. 271, and charts.] 9 As the strength of the field, due to the current, is always strictly proportionate to the capacity of the current to produce other physical effects, we have a means, not only of comparing the forces of diflfer- 9 The refined methods of determination used are fully described by C. A. SCHOTT in App. 8 of the same for 1881. For an elementary explanation of these methods see TROWBRIDGE : New Physics, p. 142. See also A. GRAY : Absolute Measurements in Electricity and Magnetism, p. 5 ; F. E. NIPHER : Theory of Magnetic Measurements, P- 46. Tkc Galvanoscope and the Galvanometer. 41 ent currents, but, by comparison with the earth's magnetism, of determining the actual dynamic value of any current, in terms of the fundamental units of space, mass, and time (91). A unit magnetic pole weighing i gram, and free to move in a horizontal plane, under the action of the earth's horizontal force, would require, at the end of i second, a velocity equal to 202.6 centimetres per second, if the experiment were made in Washington, D. C. (See p. 40.) 95. The Galvanoscope and the Galvanometer. — A magnetic needle provided with a conductor through which a current may be passed in order to deflect it from the meridian (86, /;), is called a galvanoscope or detector. When to these is added a graduated scale or dial, the instrument becomes a galvanometer. In order that the angle of deflection of a needle under the influence of any current shall bear a definite ratio to the value of such current, certain precautions in its mechanical construction are necessary to be observed. It is essential that the field produced by the current should, like that of the earth, be so large in comparison with the needle, that the motion of the latter within it, when deflected, shall not appreciably change its relation to the entire field. FIG. 33. Needle in Circular Loop. galvanometer consists of a single circular turn or loop formed in the conducting wire ; in the center of the loop is suspended the needle, which in length should not exceed -^ the diameter of the loop. Such an organization is shown in Fig. 33, in which n s is the suspended needle, and P N the looped conductor which surrounds it. principle of action may be understood by reference to Fig. 34. Let the magnetic needle n s be suspended in the earth's magnetic meridian N S. If now the conducting wire or loop be placed in the plane of N S, and we suppose this wire to be traversed by a current capable of producing a magnetic field precisely equal in strength to that of the earth, the needle will swing toward a position represented by the line A B, at right angles (or 90°) to the one originally occupied. But the two antagonistic forces being equal, the needle will come to rest in a position half-way between N and B, called the resultant. This coincides with the line Ai, which forms an angle of 45° with the zero or o° line N S. Now if we double the strength of the current, and consequently that of the field produced by it, it will partially overpower the earth's field, and the needle will assume the position corresponding to the line A2, which is an angle of 63^° nearly. If we again double the strength of the current, we shall increase the deflection to 76°, represented by the line A4- In geometrical language, the line N4 is termed tangent to the arc or Character of Electrical Measurements. 43 page 55), will always be proportionate to the strength of the current by which the corresponding deflection was caused. The actual construction of this useful instrument will be described in detail elsewhere (102). 97. Character of Electrical Measurements.— The qualities of an electric current by virtue of which, as we have seen, it is enabled to exert force, to produce physical effects, or, in technical language, to do work, are three in number, viz: (i) quantity, variously called volume, or strength of current; (2) potential, variously called pressure, tension, and intensity,10 and (3) duration, or time occupied in doing the work. The value of the first two of these properties, in the case of any particular current, is dependent not only upon the circumstances of its origin, but upon the special characteristics of the conductors which the current is compelled to traverse. Hence there are two distinct classes of electrical measurements: (1) those which are applied directly to electricity itself, either in a static or in a dynamic condition, that is to say, as a stationary charge or as a flowing current, and (2) those which are applied to the conductor which a current is or may be compelled to traverse. 98. Characteristics Capable of Measurement.— Electricity itself, whether in a static or a dynamic condition, has but three properties susceptible of quantitative measurement, viz : (i) quantity, (2) potential, and (3) duration. Electric conductors have four qualities which may affect the value of the currents which traverse them, and which, in like manner, are susceptible of measurement, viz : (4) magnitude (length, breadth, and thickness), (5) weight, or mass, (6) temperature, and (7) conductivity, or the reciprocal of this, called resistance. All these considerations must be taken into account in performing any electrical measurement. 10 The French scientific writers have always been accustomed to use the term '»tensite in the sense in which we use the term quantity or volume. The frequent translation of this word by the English term " intensity," which has in fact a wholly different signification, has been the cause of no little confusion in electrical literature. Not all these instruments are required in making every measurement, for one or more of the unknown conditions may be arbitrarily assumed, or they may be determined from others which are known, as we shall hereafter frequently have occasion to note. 100. The Ammeter, Voltameter, and Calorimeter. — The instrument for measuring quantity of current need not necessarily be a galvanometer, although in telegraphic work this is used practically to the exclusion of everything else. Currents may also be measured by the attractive force of an electro-magnet (83,^), as in the instrument called the ammeter, or by ascertaining the volume of gas evolved in a unit of time (83,?), in which case the instrument is called a voltameter, or by measuring the heat developed in a unit of time (83,/), in which case it is called a calorimeter. All these instruments find frequent use in general electrical investigations, but are less convenient than the galvanometer for measurements in connection with telegraphy. 101. Apparatus Required by the Student.— The student who desires to obtain a thorough knowledge, not only of the art of telegraphy, but of the principles of physics and chemistry upon which that art is based, is earnestly advised to supply himself, in the first instance, with his own apparatus. The comparatively small cost of the necessary outfit will be many times repaid in the value of the clear and definite experimental knowledge which this means alone will enable him to acquire. It is for many reasons advisable that two students should work together, as experience has shown that the study is rendered far more interesting, and that much more rapid and intelligent progress may be made in this way. The following list of apparatus and supplies will serve the requirements of two students, the approximate cost of each item being given : tangent galvanometer and rheostat are almost absolutely necessary in the experimental investigation of electrical action, and hence it is to be regretted that a sufficiently cheap but good apparatus of this kind has never been made available for the use of students and amateur electricians. It is nevertheless quite possible for an ingenious person, somewhat accustomed to mechanical tools and processes, to FIG. 35. Elevation of Tangent Galvanometer. in the edge of the ring must be of such depth that the bottom of it will be exactly 6 in. in diameter and \ in. in breadth. Such a channel will hold 38 turns (in 2 layers) of No. 22 "American gauge " double cotton-covered copper wire. The coil will require 62 feet of wire, weighing about 2 oz., and costing about 25 cents. The wire must be wound carefully and accurately in the groove or channel (this may be best done in a lathe), and the ends brought Construction of the Tangent Galvanometer. 47 out through small holes in opposite sides of the ring and through the base, as shown in Fig. 36. The ring and the wire, being first well dried, should be thoroughly coated with shellac varnish. The base B may be of hard wood, preferably turned, 7 in. in diameter and i in. thick. It is supported upon 3 equidistant leveling screws / /, which may be common screw-eyes (preferably of brass, though iron will answer), with the sharp tips filed off. The ring C is fixed firmly in a vertical position upon the base B, taking care that it is placed accurately at right angles therewith. A recess may be cut in the base, the ring being let into it, and secured by a clamping piece b of wood, made fast to the base B by two brass screws s. The magnetic needle, N S, Fig. 37, may be of a piece of watchspring i in. long and \ in. wide. Soften this by holding it in the flame of a spirit-lamp until of a dull red color, and then allow it to cool slowly. Drill a hole exactly in the center about fa in. in diameter, and file the ends into the tapering form shown. Straighten the needle with a hammer, and unless its center of gravity corresponds with the center of the hole, correct the error by filing the heavy part away. Next harden the needle by reheating it in the lamp-flame until nearly red-hot, and dropping it into cold water. It must then be magnetized, by rubbing each half separately from the center to the end, with a permanent magnet (67), being very careful to rub one end with one pole of the magnet, and the other end with the opposite pole. A jeweled center is then fitted to the hole in the needle,1 and secured with glue, or better, with white or red lead used as a cement. It is not difficult for the amateur to make a center out of glass, in case a jeweled one cannot be procured, by holding a piece of \| in. glass tube in the spirit-lamp flame, and pulling it apart lengthwise as soon as it softens. In Fig. 38 this operation is illustrated at C. E is one of the two pieces, which will be drawn out as shown, into a thread-like extremity. Fuse this thin end in the flame and a little globule will be formed, the a common sewing needle as a pivot, and if the magnetic needle is found not to balance so as to lie in a laterally horizontal position, adjust the center before the cement has firmly set. If one end of the needle appears heavier than the other, load the light end with a touch of melted sealing-wax, applied to the under side. Procure a fine straight straw, 3^ in. long, and make a transverse hole through the middle of it with a large pin ; thrust the top of the glass center carefully through this hole, so that the straw, which is to serve as an index or pointer, will lie exactly at right-angles with the magnetic needle (Fig. 37). Secure the straw to the glass center with a mere trace of glue, and set it away to dry. Make a bridge-piece D of hard wood, i in. thick, and secure it to the base by brass screws as shown in Fig. 35. This bridge-piece should be just high enough so that the center of the magnetic needle N S will come exactly in the geometrical center of the vertical ring C containing the wire. The circular board G is secured to the bridge-piece D with brass screws, the sewing-needle (point upward) inserted into it for a pivot, and the card-board dial secured thereto by small brass or copper tacks, in such position that when the magnetic needle is in the plane of the vertical ring, the straw will point to zero upon the scale at each end. The horizontal wooden ring H is now laid upon the dial and fastened in place with brass screws. A circular piece of glass g is cut to the right size to lie upon the shoulder of the ring H, and may be secured in place by an elastic ring r of stout brass wire, cut to the right length, so that it may be sprung into place over the glass, and within the wooden ring, after the needle is in place. If pieces of mirror be let into the dial, they will materially aid in making accurate readings of the indications, as the index and its image will then appear coincident only when the eye is vertically over the point observed. The error arising from angular observations is termed parallax. The ends of the coil wire are carried through holes into grooves cut for the purpose on the under side of the base, and thence to two binding-screws, P N (English pattern), Fig. 35, which may be purchased for about 20 cts. each. These should be placed in the plane of the vertical ring upon opposite sides of the base, and the ends of the wires carefully soldered to them underneath the base. Binding-screws are brass clamps for conveniently attaching connecting wires to electrical instruments. They are made in many patterns, the most common types being those shown in Figs. 40 and 41. In Fig. 40, the wire is inserted into the transverse hole and clamped by turning the screw. This form is very handy for ordinary purposes, but where a very good FIG. 42. contact is essential, as in measuring apparatus, the English pattern, Fig. 41, is preferable, the wire being looped round the stem and clamped by the thumb-nut. ing two or more wires, this pattern is sometimes made with more than one nut, as in Fig. 42. Construction of the Rheostat. depend largely upon the care used in making it. The most important point is to make sure that the centers of the vertical coil and of the magnetic needle exactly coincide, and that the wire is accurately and smoothly wound upon the vertical ring. It is possible for the amateur to construct an instrument which will do quite as accurate work as those which are sold for $50 and upward by professional instrument-makers (367). 106. Construction of the Rheostat. — A convenient form of rheostat for use with the tangent galvanometer is not beyond the constructive skill of the amateur. Procure from a dealer a device called a " peg pole-changer," Stretch each piece of wire out straight, double it in the middle of its length, and wind smoothly upon a separate wooden spool, — a common thread spool will do. Commence winding at the bight or loop c, and wind double so that both ends of the wire will come on the outside of the coil, as at d d. Fasten the filled spools to the under side of the box cover, C, with long brass screws, as shown in Fig. 44. The ends of the wires on the spools must be uncovered by scraping off the cotton envelope ; then carefully cleaned with emery cloth, and soldered with rosin to stout brass wires ww, in Fig. 43 will provide for a third coil of still higher resistance (indicated in Fig. 45 in dotted lines at the right), in case one should be needed.2 The thick wire coil, made as above, will have an approximate resistance of i ohm, and the thinner one an approximate resistance of 20 ohms (125). himself with the necessary appliances, the student is now prepared to undertake an experimental investigation of the laws of the electric current. Four gravity cells should be set up in accordance with directions in Chapter II, using pure water as directed in (21) and not s. z. solution. Arrange these in some convenient place, as on a diagram Fig. 46, the copper of one cell to the zinc of the next, and 2 These resistance-coils, before being mounted, may with advantage be dried for several hours in a hot, but not too hot, oven, and when taken out should be instantly immersed in a hot mixture in readiness for the purpose, composed of 10 parts by weight of rosin and i part of white wax. Let the compound cool with the coils in it, removing the latter just before it sets. Heat them again, if necessary, enough to remove the surplus material. Effect of Varying Number of Cells in Series. 53 the free copper and zinc terminals, by means of pieces of copper wire about 3 ft. long, to the binding screws P N of the galvanometer. The cells are now said to be arranged in series, both with each other and with the galvanometer. At first, little or no effect will be observable upon the needle of the galvanometer ; but in the course of a few hours a deflection may be observed, which will slowly increase. Leave the apparatus alone, except to tap the galvanometer occasionally with the finger to facilitate the movement of the needle, until it indicates about 58°, when the cells may be considered to be in good working condition. 108. Effect of Varying Number of Cells in Series.— Let the student now carefully observe the effect produced upon the needle of the galvanometer by varying in the number of cells in series with the coil. The results will be found to be something like the following: As elsewhere stated (96), the effective strength or quantity of current is always in the ratio of the tangents of the angles of deflection. Hence we have, in the above experiment, the apparently paradoxical result, which is nevertheless susceptible of rational explanation (132), that under the conditions stated, quadrupling the number of the cells in the circuit only increases the quantity of current in the ratio of 135 to 160, or about 18 per cent. no. Cells in Parallel. — Finally, connect all the copper terminals to one terminal of the galvanometer and all the zincs to the other, as in Fig. 48. This is termed connecting in parallel, or multiple-arc. The result will be again different, as follows: FIG. 48. Cells in Parallel. in. Increasing Length of Conducting Circuit.— Leaving the cells and the galvanometer connected in the manner last described, let the current next be made to pass also through the length of the 2 Ibs. of No. 18 copper wire, which will be in linear measure a little over 300 feet. The deflection of the needle will now fall from 73 J° to about 59 J° (tangent 1.70). This experiment proves that when the current is made to pass through the long copper wire, under the conditions of the experiment, its quantity is diminished to about one-half the original amount. 112. Next place the galvanometer in circuit with one cell, as we did once before, and found the deflection to be 53^° (tangent 1.35). Insert the long copper wire in circuit with the galvanometer and cell, and we get a deflection of about 44° (tangent 0.965), showing that the quantity of current has been diminished about one-third. 113. Leaving the long copper wire still in circuit with the galvanometer, add another cell, making 2 in series. The deflection now becomes about 51° (tangent 1.23), and by adding still another cell, making 3, we get a deflection of 53^° (tangent 1.35), exactly what we had with one cell when the copper wire was not included in the circuit. specting the electric current, which are that its quantity may be affected,— -first, by varying the length of the conductor which it traverses, and second, by varying the number of cells in series in the battery from which the current is derived. 115. Resistance. — What is true of the copper wire is also true of all known substances, — namely, that they oppose a certain and definite resistance to the passage through them of an electric current, and the quantity of current which passes, other things being equal, is in every case inversely proportional to the resistance which it encounters in the circuit (127). In other words,, the greater the resistance the less the quantity of current, and vice versa. 116. Conductors and Insulators. — Although all bodies offer more or less resistance to the passage of the electric current, there is an enormous difference in the resisting capacity of different substances. Those which offer comparatively little resistance are called in a general sense conductors of electricity, while those that offer great resistance are termed insulators. This distinction, like that, for example, between heat and cold, is wholly relative and not absolute. The most perfect known conductors offer some resistance to the current, and the most perfect insulators known permit some current to pass. But the actual difference in some instances is almost beyond the power of the mind to grasp. It is difficult to find any comparison which will give a tolerably good idea of the extraordinary difference between the electrical resistance of these two materials (copper and gutta-percha). It is about as great as the difference between the velocity of light and that of a body moving through one foot in 6700 years ; yet the measurements of the two quantities are daily made with the same apparatus and the same standards of comparison. This fact is well calculated to give an idea of the range of electrical measurements, and the perfection to which the instruments employed have been brought. — FLEEMING JENKIN on Submarine Telegraphy, in North British Review* December, 1866. 117. The division of bodies into the two classes of conductors and insulators, though in a certain sense arbitrary, is very convenient in practice. In telegraphy, the term conductor is applied toall substances which are used in any manner as a portion of the conducting circuit, while on the other hand, the term insulator is applied to all substances which are employed to confine the electrical current to such conductors, by preventing its escape in undesired directions. Following is a list of some of the substances so used, arranged as nearly as possible in the order of their specific conductivity : The conducting power of all alloys or mixtures of different metals is very much less than that of any one of the metals of which they are composed.2 The air is the most perfect non-conductor known, even when charged to saturation with aqueous vapor, but it should be remarked that when the moisture of such vapor is deposited upon the surface of insulating supports, it may form a conducting film of water. 1170. Specific Resistance of Different Metals.— The resistance referred to in (115^, is specific resistance, a quality which depends, in some way not definitely understood, upon the internal molecular structure of each particular substance. Thus an iron wire of the same weight and thickness as the copper wire used in the preceding experiments (in, 112) would offer nearly 6 times as much resistance. If the resistance of a pure copper wire of a certain length and diameter is known, the resistance of other wires, of similar dimensions but of other metals, may be found by the following rule : 118. Conditions Affecting Resistance. — In the case of a body having a certain specific resistance, the actual measurable resistance depends upon certain conditions, viz. : (i) Temperature. — The resistance of all metals increases with the temperature. The converse of this is true of most liquids at temperatures above the freezing point (162). resistance. Every resistance capable of being measured, must necessarily be equal to the resistance of a certain length of a standard conductor ; therefore resistance may be expressed in terms of length. Thus a telegraph line made up of two or more sections of wire, of unequal thickness or gauge, and so presenting a different resistance per mile of length, may be expressed in terms of the resistance of a given length of a standard wire : that is to say, the actual resistance of any telegraph line must represent and be equal to the resistance of a certain length of wire of the standard gauge. This length is called the reduced length of the line. The convenience of this mode of reducing resistance to terms of length in making tests and measurements of lines will appear hereafter. 119. Provisional Theory of Electricity.— Before undertaking to analyze and explain the results which have been observed in the foregoing experiments, it will be convenient for the student to form some sort of a mental conception of the agency which produces the phenomena observed. A distinguished electrical engineer has remarked : The student of electricity, in considering the various phenomena which come under his notice, must of necessity form some theory in his mind as to the nature of the element with which he has to deal ; and as philosophers are not in accord as to its nature and the theory of its action, the choice must to a novice be a difficult one. Without, therefore, in the least offering any opinion on this point, I would advise him, until his ideas are more matured, to regard electricity as a substance like water or gas, having a veritable existence, and also easily converted into heat and, vice versa, in other respects indestructible. LATIMER CLARK: Electrical Measurement, p. vii. 120. Mechanical Analogue of Electrical Action.— According to this manner of looking at the question, we may regard a voltaic cell or a dynamo-electric machine as a sort of pump, by which positive electricity is pumped through an endless channel or Conception of Potential and Electromotive Force. 59 conduit, as water might be pumped through a pipe to the top of a hill, and thence allowed to flow back in a definite channel to the foot of the pump from whence it started. This illustration, if fixed in the mind, will materially aid the student in forming a useful mental conception of the character of the flow of electricity in a circuit of conductors. 121. Conception of Potential and Electromotive Force. — When water is pumped to an elevation by the application of power and then allowed to run back to its original level, it is capable of being made to do work in the course of its descent by means of water-wheels or otherwise, and it is obvious that the amount of work it is capable of doing under these conditions depends upon three things: (i) the height of the fall, (2) the quantity of water, and (3) the length of time the effect continues. We may express the condition of affairs by saying that the water which has been raised has a certain potential energy \ which may be defined as capacity to do work, and for brevity we may call it potential. We may, therefore, for present purposes, regard electricity as a material fluid to which a certain potential has been given by the action of a battery or of a magnetoelectric machine (80), and which is therefore capable of doing mechanical work, as is the case with the descending water. That quality of a voltaic cell, or of a magneto or dynamo-electric machine, by virtue of which it confers potential upon electricity is termed electromotive force^ usually abbreviated to e. m. f. 122. Practical Electric Units. — The units offeree and work, and their relation to force of gravitation, have already been referred to (91), and it has also been explained (94) that a definite quantitive relation exists between mechanical force and the force of an electric current. This fact enables us to base our practical units of electrical measurement upon absolute units ; or in other words, our practical units are derived from constants furnished by nature. The relation or law connecting the two forces is as follows : The force which a given current traversing a circular arc exercises upon a magnetic pole of given strength situated at its center, is equal to the strength of the pole multiplied by the strength of the current and also by the length of the arc, and divided by the square of the radius or semi-diameter ; that is to say, the distance from the wire from the magnet pole. The names which have been given to the practical electrical units are derived from the names of philosophers of various nationalities who have distinguished themselves by electrical discoveries and investigations. 123. The Ampere. — The unit of current is called the ampere.8 It is equivalent in value to -fa of the absolute or c. g. s. unit of current (91). The actual value of any current within the range of the instrument may be determined from the indications of a properly constructed tangent galvanometer. This is' done by the aid of the following rules : (i; Given the number of turns and the mean radius of the coil of the tangent galvanometer, the observed deflection, and the horizontal force of the earth's magnetism at the place of observation (94), to find the current in amperes: RULE. — Multiply together the mean radius in inches, the tangent of the deflection, the horizontal magnetic intensity of ihe earth in dynes, and the reduction factor 4.0425, and divide the product by the number of turns in the coil. The quotient is the current in amperes. current and the horizontal intensity, to find the deflection. RULE. — Multiply together the number of amperes and the number of turns, and divide this product by the product of the mean radius in inches, the horizontal intensity in dynes, and the rednction factor 4.0425. The quotient will be the t ingcnt of the deflection. * AMPERE (ANDRE MARIE), an eminent French philosopher and mathematician, in honor of whom the unit of current received its name ; born at Lyons, 1775. He became inspector-general of the university (1808) ; professor in the Polytechnic School (1809) ; and Member of the Institute (1814). Having' made important discoveries in electro-magnetism, he published (1822) his Collection of Observations on ElectroDynamics, a remarkable work. " The vast field of physical science," says Arago, 41 perhaps never presented so brilliant a discovery, conceived, verified, and completed with such rapidity." He subsequently published his Theory of Electro- Dynamic Phenomena, Deduced from Experiments (1826). Died in Marseilles, 1836. 4 Each unit in the metric system has its decimal multiples and sub-multiples ; that is to say, measures larger or smaller than the standard unit. These multiples and sub-multiples are denoted by prefixes, derived from the Greek and Latin languages respectively, placed before the names of the units, as follows : (iii) Example. — The earth's magnetism in Toronto, Ont., being the directing force of a galvanometer having a lo-in. coil, how many turns must be put on it in order that a current of 0.96 amperes shall give a deflection of 60° ? From the above explanations and examples, it will he seen that a standard galvanometer may be constructed, from which it is always possible, knowing the force of the earth's magnetism, to determine the value of any electric current in amperes. In some cases, tangent galvanometers are graduated so that the amperes may be read directly without calculation. Such an instrument is called an amperemeter, or more commonly, an ammeter (369). 1233. The Coulomb. — The quantity of current which traverses a circuit in i second, when the strength of current is i ampere, is termed a Coulomb. f> It is a unit which is of little or no practical utility in ordinary telegraph work, or in fact for any other purpose, and is referred to here only because it has been given a place in the accepted system of electric units. 124. The Volt. — The unit of electromotive force is called the volt.6 It closely approximates that of a single sulphate of copper or gravity cell in good condition (24), so that in telegraphic work it is usually accurate enough for practical purposes to estimate i cell equals i volt. Accurately, i gravity cell has an e. m.f. of 1.07 volts. This value is subject to slight variation from various causes. It is not much influenced by temperature (153, note). 125. The Ohm. — The unit of electrical resistance is called the ohm.7 It is equal to the resistance to a column of pure mercury, i sq. millimetre in cross-section and 106 centimetres (more or less), in length,8 at a temperature of o° Centigrade or 32° Fahrenheit. 5 COULOMB (CHARLES AUGUSTIN DE), a distinguished mathematician, born at Angouleme, France, 1736. He is regarded as the founder of experimental physics in France. The theory of electricity is largely indebted to the investigations of this philosopher. Died, 1806. 6 VOLTA (ALESSANDRO), born at Como, Italy, 1745 ; was first professor of physics at Como, and afterward in the University of Pavia, where he taught and studied for 30 years. In 1782, he invented the electrical condenser (317), and finally arrived at the invention of the famous cell which bears his name (8), which he described in a letter to Sir Joseph Banks in 1800. Summoned to Paris by Napoleon, he received the gold medal of the Institute, of which he became a member in 1802. His works were published in 9 volumes, in Florence, in 1816. Died, 1827. 7 OHM (GEORG SIMON), born at Erlangen, Bavaria, 1787 ; studied in his native city ; was appointed (1817) professor of physics at the Jesuit college of Cologne, director of Polytechnic School at Nuremburg (1883), and professor (1849) at Munich, where he died in 1874. He discovered the so-called Ohm's law (124), which he published in 1827, and for which was awarded the Copley medal by the Royal Society of London. given in the tables, pp. 94, 112. 126. Resistance of Liquids. — The resistance of liquids is enormously greater than that of metallic substances. The relative specific resistances of some of the voltaic solutions used in telegraphy are as follows : 9 Saturated solution sulphate of zinc 17,330,000. Table iv, on the next page, contains the results of more recent determinations of the specific resistance of copper and zinc solutions at various temperatures, computed from the experiments of Becker.10 As the temperature rises, the resistance falls off. This effect is further referred to in (164). of Sir William Thomson, appointed a committee on electrical standards, which, after a long series of experiments by eminent physicists, determined the value of the ohm to be nearly that of a column of pure mercury 105 centimetres long and i square millimetre in cross-section, at temp. o° centigrade, and officially caused resistance coils made of wire of an alloy of platinum and silver to be issued as standards. Resistance coils copied from these standards are known as B. A. units or ohms. More recent careful determinations of Lord Rayleigh and many others have proved beyond doubt that the B. A. unit or ohm is more than i per cent, too small. An attempt has accordingly been made to substitute for the old standards new ones of the corrected value. In accordance with the recommendation of the International Congress of Electricians, held in Paris in 1884, a legal ohm is denned to be a mercury column of the above section, and 106 cm. in length. The exact ratio is : At the meeting of the British Association in September, 1890, it was recommended that the value for the mercury column of 106.3 cm- be substituted for the 106 cm. of the International Congress, and it is not unlikely that this value may ultimately be adopted. In Germany, the Siemens unit (known as the S. U.) is largely used, and many of the older instruments now in use in the United States are adjusted to this standard. It is designed to be equal to a column of mercury i metre long and i sq. mm. crosssection at temp. o° C. 10 F. JENKIN : Electricity and Magnetism, 259. The maximum conductivity of s. z. solution is 23.5 per cent (s. g. 1.286) according to KOHLRAUSCH : Physical Measurement, p. 326. For other tables of resistances of liquids, see SPRAGUE : Electricity, etc. (2d ed.), 298; STEWART and GEE: Elementary Practical Physics, 219; NIAUDET : Electric Batteries (Fishback's Translation), 255 ; PRESCOTT : Electricity and Elec. Tel., 182. For method of measurement see F. KOHLRAUSCH : Jour. Soc. Tel. Eng. xiii, 290. 127. Ohm's Law. — The fundamental relation which exists in every electric circuit between electromotive force, resistance and current, is expressed by Ohm's law, which may be formulated in the following propositions : (i) In any electric circuit, the current is the quotient of the electromotive force divided by the resistance ; hence the current in amperes maybe found by dividing the e. m. f. in volts by the resistance in ohms. (ii) In any electric circuit, the electromotive force is the product of the current and the resistance ; hence the total e. m. f. in volts may be found by multiplying together the current in amperes and the resistance in ohms. (iii) In any electric circuit, the resistance is the quotient of the electromotive force divided by the current ; hence the resistance in ohms may be found by dividing the e. m. f. in volts by the current in amperes. 128. Joule's Law.11 — The relation which exists between current and mechanical work is expressed by Joule's law, which may be formulated in the following propositions : 11 JOULE (JAMES PRESCOTT), born in Salford, England, 1818. A self-taught philosopher, distinguished for the extent, originality, and accuracy of his physical researches. He ascertained in 1841, the law of the evolution of heat by the electric current (128), and determined in 1850, the numerical ratio of equivalency between heat and mechanical force (92). His discoveries, which are too numerous to permit more than general (iv) In any electric circuit, the rate of doing worK is the product of the e. m. f. and the current ; hence the rate in which work is being done in watts (150) may be found by multiplying together the e. m.f. in volts and the current in amperes. (v) In any electric circuit, the rate of doing work is the product of the current multiplied into itself and into the resistance ; hence rate of working in watts may also be found by multiplying together the resistance and the square of the current in amperes. gram, Fig. 49, we may trace the circuit as follows : Beginning at the copper or the positive pole of the battery, thence through the 62 feet of copper the zinc Z or negative pole of the battery ; thence in succession through the s. z. solution and the s. c. solution S to the copper plate C of the first cell ; thence to the zinc plate Z of point, the copper plate of the terminal cell, is reached. 131. Internal Resistance of the Cell. — The solution in each cell may be regarded as a liquid conductor of cylindrical form, having a length of about 3 in. (the average distance between the copper and zinc plates) and a cross-section of about 28 sq. in. When a cell is in good working condition, the resistance of the contained liquids, at ordinary temperatures, is about 4 ohms, and may be regarded as mention here, have been intimately related to the remarkable theory of the correlation of the physical forces (p. 38, note 8) which was developed by Mayer, Helmholtz, Seguin, Faraday, and Grove. His researches in electro-magnetism, particularly in respect to its application as a motive power, were extensive and important. Honors were conferred on him by almost every learned society in the world. His scientific papers were collected and published by the Physical Society of London in 1884. Died 1889. approximately equivalent to that of 250 feet of copper wire of the thickness of that in the coil of our galvanometer (103). The actual resistance of the zinc and copper plates of each cell, being at most but an insignificant fraction of i ohm, may in the present instance be disregarded in our computations. 132. First Case. — In the first example, we begin with 4 cells in circuit in a single series, as shown in Fig. 50. This figure is a diagrammatical or conventional illustration of precisely the same i thing which is shown in Fig. 46. The I zinc plate of each cell is represented by a thick black line, and the copper by a thin line. The symbol for the galvanometer explains itself. In like manner, Fig. 51 corresponds to Fig. 47, and Fig. 52 to Fig. 48. In Figs. 51 and 52, a black dot at the intersection of two wires indicates that they are electrically united at the junction. This conventional representation of batteries, galvanometers, circuits, and other appliances will be employed hereafter in this work (208). In this case, each cell has an approximate e. m.f. of i volt (124), this value depending not at all upon the size of the element, but solely upon its chemical constitution. The aggregate £.;#./] of the 4 cells of the series is therefore 4 volts. The aggregate resistance of the 4 cells is 16 ohms, and that of the galvanometer r ohm. We may neglect also the inappreciable resistance of the short connecting wires between the battery and the galvanometer, and call the sum of the resistances in the circuit (battery and galvanometer) 17 ohms. By Ohm's law (127, i), we divide the e. m.f. 4 (volts) by the resistance 17 (ohms), and our quotient is 0.235 (amperes). With 3 cells in -like manner, we have an e. m.f. of 3 volts, an aggregate resistance of 13 ohms, and by Ohm's law a current of 0.230 amperes; and so in the remaining cases. Continuing this method of procedure, we get results which may be tabulated as follows : We find, therefore, that the tangents of the angles of deflection are in proportion to the strength of the current in amperes, as computed by Ohm's law from known electromotive forces and known resistances. needle shows, and as might have been inferred from the fact that the current from each series of cells does not now pass through the other series, nor encounter its resistance. Neither is the e. m.f. of one series superimposed upon that of the other series as before. A little reflection will make it clear that the present arrangement is precisely equivalent to 2 cells in series, each having copper and zinc plates of double the original area. Hence we may consider the cross-section of the liquid conductor to be doubled, while its length remains unaltered, from which it follows that its resistance is but half what it was originally (118). 134. Law of Joint Resistances.— The law determining the resistance of any circuit which divides into two or more branches which reunite at another point, is a general one, and applicable in all such cases, whether of batteries or of conductors. The resistance offered by two or more such branches is termed their joint resistance, and is computed by the following rules : group. The reciprocal of any number is the fraction obtained by dividing unity (or i) by that number; and the reciprocal of any common fraction, is that fraction itself inverted. Thus the reciprocal of 2 is \ or 0.5 ; and conversely, the reciprocal of 0.5 or \ is 2. The reciprocal of J is f . A table of reciprocals is given on page 67. Any sum multiplied by the reciprocal of a number is equal to the same sum divided by the number corresponding to the reciprocal. In the table, the reciprocals are those of whole numbers, but it is easy to extend their use to decimals, or to mixed numbers, by shifting the decimal point ; thus, the 135. In the present case we have 2 branches, with' a resistance of 8 ohms in each branch. Hence we have 8x8 = 64; 8 + 8= 16; 64 -^- 1 6 = 4 ; add galvanometer i, and we have as total resistance 5. Dividing the e. m.f., 2, by this amount gives a current of 0.4 amperes. We have therefore : 136. Third Case. — Next we have (no) the 4 copper terminals connected to one terminal of the galvanometer and the 4 zincs to the other terminal, as in Fig. 52. In this case, by the rule (134), the reciprocal of 4 is 0.25 ; the sum of the four reciprocals is therefore i, the reciprocal of which is i, and this added to the galvanometer resistance i, makes a total of 2, while the e. m. f. is now reduced to i. Hence, we have in this case: in which we found that having 3 cells in circuit with the galvanometer, and 300 feet of a certain gauge copper wire, the deflection apparently indicated that we produced exactly the same current in the circuit that we did with i cell when the copper wire was not included. Let us see whether Ohm's law accounts for the result. We find from the copper wire table (p. 94) that the resistance of the length of wire included is approximately 2 138. Ohm's law is therefore confirmed in every particular by the results of experiment, and observation, and we learn, moreover, the important fact that the quantity of current traversing any given circuit may be varied either by varying the electromotive force or by varying the resistance. 139. We also learn from Ohm's law, as interpreted by the experiments which have been made, that every portion of an undivided or non-branching circuit is traversed by the same quantity, or number of amperes^ of current at the same time, without reference to its relative resistance. 140. Currents in Branch Circuits.— When any circuit divides into two or more branches a current traversing that circuit distributes itself between these branches inversely in proportion to their respective resistances, or, what is the same thing, directly in proportion to their several conductivities. The branches are also termed shunts or derived circuits. Each such branch may be regarded as a shunt to all the other branches in parallel with it. The word shunt is of English origin, and is derived from the analogy of a railroad siding where trains pass each other, which in that country is known as a shunt. 141. Electric Potential. — Having thus gained some experimental as well as theoretical knowledge of electromotive force (121), resistance (115), and current (91), the student should next endeavor to acquire a definite understanding of the meaning of the term potential. The resemblance between the behavior of electricity and that of a material fluid like water has already been pointed out (120). Recurring to this analogy, if we assume a stream of water to be flowing through a closed pipe, we know that as soon as the flow has become steady, exactly the same number of gallons per minute will pass through every cross-section of the pipe, whatever may be the difference in its diameter at different points. This is exactly analogous to that which occurs in the case of an electric current (139)- per square inch is by no means equal throughout, and this is true whether the pipe is level and whether it is of uniform diameter or otherwise. As we proceed along a horizontal pipe in the direction of the flow, we observe the pressure becomes less and less as we go farther away from the supplying reservoir. potential, occurs as we recede from the source of electricity, just as there is a fall of pressure in the water-pipe. For example, let Fig. 53 represent a vessel ~ filled with water.12 The tap at C is closed, and the water stands at the same level in all the vertical tubes, showing that no difference of pressure exists, and consequently there can be no current of flow in the liquid. But when the tap at C is opened, as in Fig. 54, it will be observed that the level in the several vertical tubes stands lower and lower as we pass from A toward C. The height of water in each tube indicates the pressure which exists at the point of its junction with the tube B. This difference in hydrostatic pressure between different points in the pipe produces the flow of water which we call a current. The original cause of the flow is manifestly the force which lifted the water in the first place to a point above the level of the pipe B, and thus conferred upon it the pressure or potential which it now has (121). Therefore we may say without error, that electromotive force causes potential to exist. When resistance is removed, a fall of potential occurs at some point, and this fall of potential gives rise to an electric current. Therefore the fact of the existence of an electric current is conclusive evidence of the existence of a difference of potential between two different points in the circuit through which the current flows. 1S This excellent illustration is from Professor ELROY M. AVERY'S Elements of Natural Philosophy, of which the chapter on electricity and magnetism has been separately published by Sheldon & Co., New York. The fall of potential between any two points in a circuit bears the same ratio to the fall of potential in the whole circuit that the resistance between those points does to the total resistance of the circuit. In other words, in the whole or any portion of a circuit, the fall of potential is always in proportion to the resistance. In Fig. 55, the horizontal pipe is in two portions of different diameters, and in this case it will be observed that the fall of the pressure is more rapid along the smaller than along the larger section. 145. Graphic Illustration of the Electric Circuit. — We may represent by a diagram all the essential characteristics of the electric circuit in a manner first pointed out by Ohm in 1828. For example. let the ring in Fig. 56 represent a conductor of uniform resistance having a source of electricity at the point A. The electricity from this point will be diffused over both halves of the ring; the positive going toward a and the negative toward b, both uniting at c. As the conductor is assumed to be homogeneous, it follows that equal quantities of electricity traverse all sections of the ring at the Fig. 56. Geometrical same time (139). If we assume that the flow of illustration of Ohm's the current from one crOss-section of the ring to another is due to the difference of potential which exists between the two points (143), and that the quantity which passes is proportional to this difference of potential (144), it follows that the positive and negative currents, proceeding in opposite directions from A, must exhibit a decrease in potential the farther they recede from the starting point. This decrease in potential may be graphically represented in a diagram, the analogy of which to the hydraulic apparatus of Fig. 54 will be apparent upon inspection and comparison. Suppose the ring of Fig. 56 to be stretched out in a straight line A A', Fig. 57. Let the vertical line A B (technically termed an ordinate) represent the positive potential at A, and A' B' in like manner the nega- tive potential at A'; then the line B B' will denote the value of the potential in all parts of the circuit by the correspondingly varying lengths of the vertical ordinates at any point between Kc or c A'. The quantity of the current is proportional to the steepness of the fall. This may be considered also as a graphic representation of Ohm's law (127). 146. Fall of Potential in a Non-homogeneous Circuit. — In practice, in the circuits employed in telegraphy, the conductor is never homogeneous, but, like the water-pipe referred to in (144), is made up of several conductors of varying conductivity. To illustrate this condition of things in a diagrammatic form, let the conductor A A', Fig. 58, consist of two portions having respectively different cross-sections. If we assume the cross. section of A //, for example, to be greater pass through all sections in equal times, as stated in (139) and (141), the difference of potential between the extremities of the thicker wire will be only two thirds what it would be in the case of the thinner wire of equal length. Hence, the fall or drop in potential will be less in the thick than in the thin wire, as shown by the line Br, in Fig. 58. The greater therefore the resistance of the conductor, the greater the fall of potential. This result is expressed in the following law : In any electric circuit, the fall of potential is directly as the specific resistances (117) of the sei'eral conductors composing it, and inversely as the area of their cross-sections. various parts. 147. Electrostatic Capacity. — A body charged with electricity in a static condition, as, for example, a long submarine cable, a condenser (317) or the well-known apparatus called the Leyden jar, is said to be in a state of electrification. This effect is also observable upon well-insulated land lines of considerable length, and is one which in certain special methods of telegraphy needs to be taken into consideration, as will hereafter appear. The quantity of static electricity (82) thus held by any conductor, or that which any body is capable of containing, is termed its capacity. This is often called also electrostatic capacity and inductive capacity. The Watt. 148. The Farad. — The unit of capacity is called \hzfarad,™ but the capacities required to be measured in telegraphy being usually very small, they are more conveniently expressed in micro-farads (p. 60, note 4). Further explanation of this subject is reserved until the effects of static electricity upon telegraph lines require consideration. 149. Power, or Rate of Work. — It has been stated elsewhere (92) that every electric current is capable of doing a certain amount of work. This definite amount of work may, however, obviously be done in a greater or less length of time, that is to say, at a different rate, and this rate of work is called power. 150. The Watt. — The electric unit of power, or rate of working, is called the watt.^ It equals i volt multiplied by i ampere, or 7J^ of a mechanical horse-power. In any circuit the power equals the square of the current in amperes multiplied into the resistance in ohms. .238 calorie. 13 FARADAY (MICHAEL), a distinguished chemist and natural philosopher ; born in Newing'On, England, 1791. He received but little education, and while young was apprenticed to a bookbinder. While working at this trade, a scientific book fell into his hands, which he read with avidity, and was thus led to devote himself to the study of electricity. In 1813 he obtained the appointment of chemical assistant under Sir Humphry Davy at the Royal Institution. In 1821 he discovered magnetic rotation. In 1831 he began the publication of his Experimental Researches in Electricity, beginning with the induction of electric currents (151) and the evolution of electricity from magnetism (73). Three years later he discivered the principle of definite electrolytic action (154). His original papers, including a wide range of contributions to modern science, are too numerous to mention in detail. In 1833 he was appointed professor of chemistry in the Royal Institution, which chair he continued to hold until his death. He was a member of many learned societies of Europe and America. Died 1867. 14 WATT (JAMES), an eminent mechanical engineer, born at Greenock, Scotland, 1736. Under his father he acquired a knowledge of mathematical instrument-making. When nineteen years of age he went to London, but soon returned and settled at Glasgow, where, under the patronage of the university, he subsequently immortalized himself by the invention of the steam-engine. Died 1819. 151. Current Induction. — An electric current traversing a conductor has a capacity of setting up or giving rise to a temporary current in a neighboring conductor. This effect is called volta induction, or, more commonly, current induction; and the temporary current thus produced is called the induced or secondary current. The originating current in such a case is termed the primary or inducing current. This effect is sometimes observed to take place between two long and well-insulated telegraph lines which are situated parallel and near together for a great distance. The flow of the secondary or induced current is in a direction contrary to that of the primary or inducing current. 152. Electrical Dimensions of the Voltaic Cell.— The practical value of any type of cell for a given purpose depends upon what is known as its electrical dimensions, and upon its constancy. The first property determines the quantity of electricity which it is capable of producing in a given time; the second property the length of time it is capable of maintaining such action. 153.— E. M. F. and Resistance of the Cell.— The electrical dimensions of a cell are stated in terms of its e. m. f. and its internal resistance. The first depends upon its chemical reaction, without reference to size, and the second is practically uninfluenced by any considerations other than the conducting power of the solutions (126), the area of their cross-section (131) and the temperature.16 The duration of the cell depends upon the quantity of material it contains and upon the energy of the chemical action within it. The gravity cell, described in Chapter II., has an e. m. f. of 1.07 to 1.08 volts, and when in good condition an average resistance of 3 to 4 ohms. 154. Quantity and Cost of Materials Consumed in the Battery. — The subjoined table shows the theoretical consumption and deposition of material in each gravity cell per ampere per hour, in fractions of an avoirdupois pound, by the aid of which the cost of producing any given current may be ascertained when the price of materials is known.17 " Heat increases the e. m.f. of a sulphate of copper cell ; it does so by affecting the solubilities of the two salts and supplying externally the energy absorbed in solution. Between 32° and 52° Fahr. there is a difference of .01 volt ; between 50° and 60° also .01, and between 50° and 100° about .025. J. T. SPRAGUE : Electricity, etc. (2d Ed.), p. 141. 17 The electro-chemical equivalent of zinc is here taken as 0.00033696 grams per ampere per second, according to the determinations of Rayleigh and Kohlrausch. A table of electro-chemical equivalents, calculated from Rayleigh's results, is given by GEORGE B. PRESCOTT, Jr., Electrical Engineer, iv. 7. .OO25Q4Q Experience shows that, owing in part to local action (57: 7), the actual consumption of zinc is greater than the theoretical, while the consumption of s. c. and the deposit of copper are found to approximate quite closely to theoretical requirements. The greater part of the actual zinc-waste in practice is due to the unconsumed residue of each zinc, which finally has to be thrown out. (6ia.) 155. The following examples show how this computation is made. Suppose i gravity cell is employed to operate a certain telegraphic instrument, whose magnetizing coil has a resistance of 3.7 ohms, and is connected with the cell by 30 feet of No. 18 copper wire. Required the theoretical cost per month of maintaining the cell, when used from 8 a.m. to 8 p.m. every day. 156. Again, suppose two telegraph lines supplied from one battery of 100 cells, each line carrying a current of 25 milliamperes (123); required the theoretical consumption per month of material, working 24 hours per day. We find, therefore, that the theoretical net cost of materials consumed in a battery under the conditions given, is less than 4 cts. per cell per month. In practice, it is usually from 4 to 5 cts.18 157. Production of Electricity in Proportion to Material Consumed. — An idea very common among amateur electricians is that it may be possible to make some change in the proportions or arrangement of the gravity battery by which its power may be increased without a corresponding expenditure of material. This is a fallacy. Electricity may in one sense be regarded as a constituent of zinc, which is set free when that metal combines with oxygen,19 and hence the quantity of electricity evolved in a voltaic cell can never exceed a certain ratio to the weight of zinc consumed. The invariable laws of chemical combination teach us, moreover, that the consumption of s. c. and the deposition of copper must in all cases maintain a fixed ratio to the consumption of zinc. 158. Consumption of Material in a Series of Cells.— Admitting the consumption of material in each cell, when two or more cells are in series, to be in proportion to the quantity of current by which the series is traversed, it follows that the cost of material (the external resistance remaining constant) must be as the square of the number of cells in series, and not in the simple ratio of the number of cells. Thus if we increase the number of cells threefold, we have three times as many cells and three times the quantity of current traversing each cell, so that the consumption of material will necessarily be ninefold. "but on the other hand its internal resistance is very small, and its local action almost inappreciable. Such a cell is well suited for telegraphic work. The diagram Fig. 59, exhibits the results 01 a test of 4 large cells, maintained in action in series with an external resistance of 0.8 ohms continuously for 108 hours. Such a current would suffice to supply 10 or 12 telegraph lines at the same time. 1 60. Effect of Temperature upon the Resistance of Metallic Conductors.— It has been stated (118) that the resistance of all conductors is affected by temperature. Unless otherwise specified, the resistance of electrical conductors is customarily assumed to be taken at 60° Fahr. 161. According to Miiller, the percentage of increase in resistance of some of the metals most employed in telegraphy between o° and 70° Fahr. is as follows : Platinum 6 per cent. The difference in the measured resistance of a telegraph line of iron wire may therefore vary as much as 13 per cent, between the extremes of summer and winter temperature in the northern portions of the United States. The resistance of German-silver and platinum-silver alloys vary but little with temperature, and hence standard resistances are made from wires of these artificial metals. 162. Effect of Temperature upon Resistance of Liquids. — The liquid mass which acts as a conductor in a voltaic cell undergoes considerable variation in resistance with changes of temperature. Of the different voltaic combinations in general use, the sulphate of copper cell is most affected in this way. Hence in experiments with this cell, it is important that the temperature be kept constant, or that frequent measurements should be made of the internal resistance and allowance made therefor. 163. Effect of Temperature upon Resistance of Daniell Cell. — Three series of tests of the Daniell sulphate of copper cell were made by Preece ; in the two first cases, the s. c. solution was saturated at all temperatures, while the s. z. solution had the same density throughout the period of observation, being saturated at about 57° Fahr. In the third case both solutions remained saturated at about 50° Fahr. The results are given in the diagram, Fig. 590. The curve ABCDE corresponds to the case in which the s. c. solution was saturated at all temperatures, while the s. z. solution was of constant density. The curve abed corresponds to the case in which both solutions remained unaltered in density. The direction of the arrows indicates the order of the experiments. In the curve ABCDE, the portion AB represents the result obtained by heating the cell from about 52° to 211° Fahr. (near the boiling point of water), and the portion BC that obtained while the same cell -,vas being cooled from 211° to 35° Fahr., nearly the freezing point of water. A similar explanation applies to the curve abcde. 164. These curves clearly show : (a) That when the temperature of a Daniell cell is raised from the freezing to the boiling point of water, the internal resistance of the cell decreases, abruptly at first, but more gradually afterward, falling from 2.12 to .66 ohms, or more than one-third. Effect of Temperature upon Battery Resistance. 79 (If) That when a cell which has been thus heated is cooled, the resistance increases at a more rapid rate than it fell off while being heated; in other words, the resistance of a Daniell cell, within the range of temperature experimented upon, is smaller before it has been heated to a high temperature than afterward, provided the heating and cooling be not done too slowly. (c) That if the cell thus cooled down be left undisturbed at a given temperature, the resistance of the cell slowly diminishes until at last, at the end of a certain period (40 to 50 hours), it returns to the value which it had before having been heated. 165. The Electro-Magnet, as improved by Henry,1 forms the most essential part of every telegraphic receiving instrument, and is the instrumentality by means of which the energy of the electric current is transformed into mechanical power, and is made to produce physical effects appreciable by the senses. Nearly every fact of importance in connection with the phenomena of electro-magnetism has been known to experimenters and observers for half a century, but the apparently anomalous and contradic- i HENRY (JOSEPH), LL.D., born Albany, N. Y., 1799; educated in the common schools of that city and in the Albany Academy, in which he became professor of mathematics (1826), and almost immediately entered upon a course of experimental investigation, during which he made numerous and important discoveries in electricity and magnetism. Although at this date the electro-magnet had become in a certain sense known, from the researches of Sturgeon ( Transactions Soc. Arts, xliii. ; Nov. 1825), it was but a philosophic toy, in which a feeble magnetic excitation was produced by currents of small e. m. f. in a short circuit. Henry's first success was the invention of the electro-magnet as we now know it, a horse-shoe of soft iron surrounded by many turns of insulated copper wire arranged in concentric layers (186), a construction which no subsequent invention has essentially modified. He next demonstrated that the difficulty of exciting magnetic energy at a distance by an electric current, which had led Barlow in 1824 to pronounce the idea of an electric telegraph " chimerical," may be completely overcome by the use of a battery of a sufficient number of cells, arranged in series (107), provided the electro-magnet be provided with a helix having a sufficient number of turns. It was the invention of Henry's electro-magnet which first made the electric telegraph a commercial possibility, and it is worthy of note that in an article published in 1831 (Amer. your. Science, xix. 400), he pointed out the applicability of the long-coil magnet to this purpose. During1 the same year he constructed an apparatus for giving signals at a distance, which was operated through more than a mile of wire carried around the walls of a room in the Albany Academy. This apparatus embodied all the essential principles of the practical telegraph of to-day. The signals were produced by the polarized armature of an electro-magnet which was made to vibrate by reversal of the current (201) and to strike a bell. In 1832 he discovered the induction of a current in a coiled conductor upon itself (196). In 1832 he was elected professor of natural philosophy in the College of New Jersey, at Princeton, and in 1846 first secretary of the Smithsonian Institution in Washington, which honorable position he continued to hotd until his death in 1878. His collected scientific papers have been published in 2 vols., Washington (1886). For many particulars of interest respecting the contributions of Henry to the invention of the electric telegraph, see Life and Work of Joseph Henry^ by F. L. POPE, and "The American Inventors of the Telegraph," by the same, in the Century Magazine, xxxv. 924 (April, 1888). It has recently become known that he was the first to discover the phenomenon of magneto electricity (62). See papers by MARY A. HKMKY, N. Y. Elect. Engineer, xiii. 27 etseq. tory character of mrmy of the results obtained has been very puzzling to the student. It was not until after the conception of the existence of a magnetic circuit (178), analogous in many of its properties to that of the electric circuit, originally due to Joule,2 had been definitely formulated in 1873 by Rowland,3 and its truth confirmed by the subsequent researches of Bonsanquet 4 and others, that it became possible to suggest an adequate explanation for many of the singular and apparently unaccountable facts which had been noticed by investigators. 166. Elements of the Electro-Magnet. — The electro-magnet may conveniently be regarded as comprising three distinct elements, the laws of each of which must be separately studied, although they all enter into the general result. These elements are (i) the wire, (2) the iron, and (3) the current. 167. It has been stated (85, d} that when a piece of soft iron is spirally encircled by a conductor, it is rendered magnetic by the passage of a current through this conductor. Such an organization constitutes an electro -magnet in its elementary form. conducting wire, coated or insulated , with nonconducting material, into what is termed a right-handed helix, shown diagrammatically in Fig. 60, in which the conventional direction of the current (31) is indicated bv the arrows, while the respective north and south poles induced thereby are designated by the letters N and S Thus, if the current the south pole was before, and vice versa. 169. Lines of Force as a Measure of the Magnetic Field. — It has been explained (93) that a conductor conveying an electric current is surrounded by a field of magnetic force, and that in such a field, the lines of force are concentric with the conductor. These lines of force may be regarded as units, in terms of which magnetism may be expressed and measured. The direction and polarity of the magnetic force is indicated by the direction and polarity of the lines, the total number of its lines is a measure of the total quantity of magnetism, while the number of them contained in a given unit of area, measured in a direction perpendicular to their direction, is a measure of the intensity of magnetism at that point. This conception of magnetic force may, perhaps, be better understood if compared to the force of gravity similarly represented. Imagine a heavy body suspended in the air, and suppose every cubic inch of the material of which the body is composed to weigh one pound. If an imaginary line be drawn to the earth from the center of gravity of each cubic inch of the suspended body, the direction of these lines would represent the direction of the force of gravity ; their total number would represent the total force in pounds ; while their density, or the number of lines per square inch area (measured perpendicularly to their direction), would represent the intensity of the force at that point. In precisely the same way as these lines represent the direction, amount, and intensity of the force of gravity in that body, so do the lines of magnetic force represent the direction, amount, and intensity of magnetism, except that in the latter there is no constant direction of action such as the downward force of gravity, the lines of force acting in both directions, as if trying to shorten their circuit, like a stretched rubber ring. The lines do not exist as such, any more than they do in the analogy of the force of gravity ; it is merely a convenient way of representing magnetism in order to facilitate the conception and computation of problems. — CARL HERING : Principles of Dynamo-Electric Machines, 18. 170. An accurate knowledge of the characteristics of magnetism is of great importance in the designing and construction of dynamoelectric machinery, and it fortunately happens that recent researches in connection with this class of work have greatly enlarged our practical knowledge of the laws and conditions of magnetic and electro-magnetic action as applied to telegraphic and other apparatus of like character. Provided we are able to calculate the intensity of the magnetic field which is produced by the influence of a known current, we have the means of calculating also the intensity of magnetism in an iron core placed within that field. When, however, the magnetiza- Unit of Magnetism. 83 tion approaches the limit of intensity which the soft iron is capable of receiving, the actual magnetization always falls short of the theoretical magnetization as calculated by this rule. 171. Unit of Magnetism. — It is customary to express intensity of magnetism, or magnetic density, as it is sometimes termed, by the number of lines of force per unit of cross sectional area, measured perpendicularly to their direction. The unit of magnetism is the equivalent of a single one of these lines of force, and is that quantity of magnetism which passes through one square centimetre of the crosssection of a magnetic field whose intensity is unity. It has been proposed to call the magnetic unit the gauss:' To illustrate, suppose a circular loop of wire like that shown in Fig. 33, p. 41, having a -diameter of 10 centimetres (3.9 in.), to be traversed by a current of 7.958 amperes. The quantity of magnetism passing through an area of i sq. cm. at the center of the loop will be i unit.6 A magnetic field in which the number of parallel lines of force per unit area is the same in every part is termed a field of uniform intensity, or briefly, a uniform field, A good illustration of such a field is that of the earth referred to in (94). The field inclosed within a circular loop of wire like Fig. 33 is not uniform, but varies in different parts, being most intense near the circumference and least in the center. 172. Magneto-Motive Force. — Recurring again to the electric conductor surrounded by concentric lines of force, as shown in Fig. 32, p. 39, it is n6t difficult to understand that if we coil such aconduc- 5 GAUSS (KARL FRIEDRICH), born in Brunswick, Germany, April 30, 1777. When very young was distinguished for his mathematical attainments ; became Professor of Astronomy and Director of the Observatory in Gottingen, 1807 ; was made, in 1816, Court Councilor and in 1845 a Privy Councilor of Hanover; after 1821 made important improvements in geodetic methods and instruments ; and after 1831 devoted much attention to the study of terrestrial magnetism. In 1833, with the assistance of his coadjutor, WILHELM EDUARD WEBER, Professor of Physics in the University of Gottingen, he constructed an electric telegraph more than a mile in length, extending from the Physical Cabinet to the Observatory in that city. This telegraph was remarkable as being the first in which magneto-electricity (73) was used ; for the ingenious but simple method employed of using a ray of light as an index of the movement of the galvanometer needle (a plan long afterward adopted by Sir William Thomson in his well-known mirror galvanometer) ; and last, though not least, as having had an actual existence for several years ; for although at first intended for scientific purposes only, it soon came to be employed as a means of ordinary correspondence as well. (SABINE : The Electric Telegraph, p. 27.) Gauss died at Gottingen, 1855. « What is known among manufacturers of electrical machinery as the English unit of magnetic induction was proposed by GISBERT KAPP (Jour. Tel. Eng., xv. 518). The unit line of force adopted is equal to 6,000 c. g. s. lines, the sectional area of the iron being taken in square inches. The English unit, therefore, is one of these assumed lines per square inch, and is commonly termed a Kapp line. tor into an elongated helix or spiral, technically termed a solenoid^ Fig. 62, and cause the current to traverse it in the direction indicated by the arrows, the lines offeree inclosed within the helix, being the resultant of those of the separate turns, assume the form represented FIG. 62. Direction of Lines of Force within a Solenoid. in the figure. In the drawing, for convenience of illustration, only a part of each line of force is shown, but it must be borne in mind that every line is in fact endless, forming a complete magnetic closed circuit returning into itself, so that different lines can never under any circumstances intersect each other. The value of the current in amperes being known, a corresponding field of definite intensity is set up within the helix. The intensity, or, as Bonsanquet calls it, the magneto-motive force of the field, may be readily calculated by the following : RULE. — Multiply the number of turns in the helix by the current in amperes and divide this product (ampere-turns) by the length of the helix in centimetres ; multiply the quotient by 1.2566, and the product will be the intensity expressed in lines of force per square centimetre, or if the length be taken in inches, the multiplier 0.3132 will give the quotient in lines per square inch. FIG. 63. Lines of Force traversing Iron Bar within the Solenoid. 173. Effect of Iron in the Helix. — If now a soft iron core be placed within the same helix, as shown in Fig. 63, the intensity of the field is materially increased, or in other words the number of lines- Effect of Magnetization upon Soft Iron. 85 of force per unit of cross-sectional area is greatly augmented. The strength of field due to the presence of the coil and its contained iron is termed magnetic induction. The difference between the number of lines per unit of area, with and without the iron, evidently gives the value of the magneto-motive force due to the iron alone. This difference may be stated roughly as about 100 to i for soft iron of average good quality. 174. Effect of Magnetization upon Soft Iron. —The graphic diagram, Fig. 64, was plotted from a series of observations made with a magnetometer -7 upon a rod of unannealed iron 10 cm (3.9 in.) long and which rises at a more or less steep angle, and which for some -distance from its origin at o continues nearly straight to the point i, and another part B 2, also nearly straight, but which is inclined at a much less angle to the horizontal, these two parts being joined by 7 The magnetometer is an instrument for the measurement and comparison of magnetic forces. It consists essentially of a magnet or needle delicately suspended in the magnetic meridian, and provided with a pointer or index, usually in the form of a ray of light reflected by a small mirror. By placing the stationary magnet whose force is to be determined at a measured distance east or west of the suspended needle, with one of its poles pointing directly toward it, it is easy, by observing the angle of deflection of the needle, to measure the attractive force of the magnet pole. For a simple apparatus and method of performing this operation see J. TROWBRIDGE : New Physics, 131. a curved portion i, 2. The first-mentioned part of the curve corresponds to the state of things when the iron core is unsaturated ; the latter part to the state when the core is more than half saturated ; while the curved intermediate portion corresponds to the intermediate state during which the core is approaching saturation (177). In the curve of results of an electro-magnet two effects are in reality combined ; that of the magnetism of the iron core, and that of the magnetic action of the coils through which the current is flowing ; this joint effect is shown in the dotted line. It is easy to separate these two values, for if the iron core be removed, and the magnetic effect of the coils alone be observed, a new set of data are obtained which, when plotted out, will yield the more gently sloping line o C. From this line two conclusions may be drawn : it slopes at a small angle, because (i) the magnetic effect of the coils is small compared with that of the iron core. It is quite straight, because (2) the magnetic effect of a coil (which of course is not capable of saturation) is exactly proportional to the strength of the current by which it is traversed, throughout the entire range of the experiment. 175. The following series of determinations, made with a coil of 500 turns surrounding an iron core 10 cm. (4 in.) long and i cm. (13-32 in.) in diameter, further illustrate this matter. The figures in the last column are the values of the magnetic moment** as calculated from the deflections produced in a magnetometer.10 form to those shown in Fig. 64. The values of magnetic moment 9 The magnetic moment of a magnet in c. g. s. measure is the product of the strength of its magnetic pole in dynes (191) multiplied by the distance between its poles in centimetres. The intensity of magnetization of a magnet is the ratio of its magnetic moment to its volume. 176. Magnetic Saturation. — It will be seen, therefore, that the proportion of ampere-turns to magnetic intensity, referred to in (174), holds good only through a certain range of magnetic increase. When the intensity has reached a certain point, the iron becomes, from that point onward, less and less susceptible to further magnetization, and though, strictly speaking, the point of absolute saturation can never be reached, there is a practical limit which cannot be exceeded.1- The approach of saturation is well exhibited in the core curve in Fig. 64, which begins to deflect when the magnetizing force reaches the vicinity of 500 ampere-turns. The cores of the electro-magnets of modern telegraphic apparatus seldom exceed 0.5 in. in diameter. It has been experimentally proved that the approach of saturation in a core of this dimension is not reached with less tuan about 500 ampere-turns, which is some 3 times the degree of magnetization ordinarily employed in telegraph magnets used in local circuits, while that employed in magnets used in main circuits is still less. An important principle in electro-magnetism is, that precisely the same magnetic effect may be obtained from a few turns of wire and a large volume of current as from a great number of turns and a small current, provided only that the number of ampere-turns remains the same. This necessarily follows from the fact that the same amount of work is done in the wire by the circuit in each case (92). -L/* 178. The Magnetic Circuit. — In the practical application of the electro-magnet for telegraphic and other like uses, it is not usual to make it in the form of a straight bar. Much better results are attained by bending the bar into the form of a \|J> or "horseshoe," as shown in Fig. 65, which enables an a manner as to form a complete Magnet. 11 For an experimental investigation of the relation between the diameter of the core, the total magnetizing force of the coil, and the force of attraction, see paper by E. L. FRENCH : Electrician and Elect. Eng., v. 445. 12 The limit of magnetization in good wrought-iron is about 125,000 (c. g. s.) magnetic lines per sq. in., or 20,000 per sq. cm. — S. P. THOMPSON : The Electromagnet, 32, 83; ibid., Dynamo-Electric Machinery (4th Ed.), 148, 149. magnetic circuit. Inasmuch as magnetism is now known to be a phenomenon pertaining to the internal molecular structure of iron, the preferable method of treating the subject is to look upon that metal as a substance which is a good conductor of the magnetic lines of force, or, as it is expressed in madern scientific language, possessing a high degree of magnetic permeability.^ 179. Magnetic Permeability. — This characteristic may be best defined as a numerical co-efficient which expresses the ratio between the number of magnetic lines formed in a space containing nothing but air, as in Fig. 62, and as denoted by the value of the line o B in Fig. 64, and the number formed in a space filled with a given quality of iron, as in Fig. 63, and as denoted by the value of the dotted line in Fig. 64-14 This ratio differs for different qualities of iron, and hence we say that the permeability of the iron differs accordingly. The higher the co-efficient of permeability, the less, so to speak, is the magnetic resistance, and the more suitable is the iron for the purposes of an electro-magnet. On the other hand, the permeability of air and of most substances other than iron is comparatively very small. 180. Law of the Magnetic Circuit. — In (172) the method of calculating the magneto-motive force of a magnetic circuit has been given. We have next to find the resistance which the magnetic circuit offers to the passage of the lines of force, a property which has appropriately been termed by Dr. O. J. Lodge magnetic reluctance. The total magnetism of the circuit, called the magnetic flux, will be the quotient of the magneto-motive force divided by the reluctance. The similarity of the law of the magnetic circuit to the law 181. Determination of Magnetic Reluctance. — If the magnetic circuit is a simple closed ring of iron, the magnetic reluctance may be calculated precisely in the same manner that we calculate the resistance of an electric circuit. The value of the reluctance is directly in proportion to Ratio, of Attractive Force to Distance. 89 of its cross-section, and is also inversely proportional to its permeability. But if, instead of a homogeneous ring of iron, the circuit be made up of different parts, differing in their magnetic reluctance, it becomes necessary to determine the reluctance of each part separately, and then add them together, as in the case of an electric circuit of like character (118). For example, Fig. 66 shows the lines of force in an endless iron ring. Fig. 67 is a similar ring cut in two, leaving an air-gap between the severed ends. It has been stated that the permeability of air is far less than that of iron (179). The reluctance of the air-gaps to the magnetic lines may be taken roughly at i oo times that of a mass of soft iron of good quality of the same form and dimensions. The case of the divided ring of Fig. 67 is equivalent to that of the horseshoe magnet and its arma- is a little way removed from the poles, and is the condition which is constantly met within the operation of ordinary telegraphic apparatus. The lines of force traverse the armature in passing from one pole to the other. 182. Ratio of Attractive Force to Distance. — It is stated in many text-books that the attractive force exerted by an electromagnet upon its armature varies inversely as the square of the distance between them. This proposition, known as Coulomb's law, would be true, if it were true that the magnetic forces are concentrated at a focal point in each pole, and that this disposition of it remains unchanged by the movement of the parts in response to the magnetic attraction. But in fact there is not, and from the nature of the case cannot be, any one law which correctly expresses this relation under all conditions. It necessarily differs with every alteration in the form of magnet and armature, and with every change in their positions with reference to each other. This is well shown in experiments1"' made with an electro-magnet having a core formed from a round bar 19 in. long and i in. thick, bent into a horseshoe, with its poles 1.25 in. apart. The distance of the armature from the poles was determined by the interposition of sheets of rolled brass .00416 in. thick, the required number of these sheets for each experiment being strongly pressed together and soldered at the edges. The following table gives the results in weights lifted, 55,000 The corresponding curve is plotted in Fig. 68. The rapid increase in the attractive force as the armature approaches the poles of the magnet is shown in a striking manner. Construction of Telegraph Magnets. 91 183. Construction of Telegraph Magnets. — Fig. 69 is a representation of an electro-magnet, such as is usually employed in telegraphy. The drawing is the actual size and proportions of a type of magnet largely used by some of the most successful American instrument-makers. The iron portion of the magnet, of the best Swedish, Norwegian, or Lowmoor soft iron, consists of the following parts: (i) the core proper, which is cylindrical in form, and is the part around which the wire is coiled : it is made in two parts, A A, usually termed the legs or branches of the magnet; (2) a rectangular bar, B, which serves to unite the two parts of the core (which are secured to it by screws), and is termed the yoke ; and (3) the armature C, which, as has been shown, is really part of the magnet, being the movable portion by means of which the magnetic force is exerted. 184. Theoretical Proportions of Telegraph Magnet— The best theoretical proportions to secure the maximum magnetic effect from a given quantity of current, has been found to be to make the four parts of equal length, the yoke being of somewhat greater cross-section than the cores, and the armature of equal cross-section, but broader and thinner than the yoke. But inasmuch as quickness of movement is one of the most important considerations in telegraphic apparatus, experience has demonstrated that these theoretical proportions may be modified with practical advantage. The dimensions and proportions of the iron cores of electromagnets have been the subject of numerous experiments in order to determine the most favorable conditions in respect to the two qualities essential in telegraphic instruments: (T) maximum attractive force with a given current, and (2) quickness of action. These properties are in their nature antagonistic, and hence it is necessary in practice to sacrifice to a certain extent the first-named desideratum in order to more completely secure the second. The results of the investigations referred to have shown that the outer diameter of the coils or helices ought to be three times that of the cylindrical cores, and that the length of each coil or helix should be equal to its diameter. These proportions are exemplified in Fig. 69, and approximate closely to those most commonly used at the present day in the United States. The magnetic intensity developed in the iron, within certain limits elsewhere set forth (174), being proportional to the quantity of current traversing the wire (measured in amperes), and also to the number of convolutions or turns of the wire, we may express the magnetism developed in the iron as a certain number of ampere-turns. 185. Effect of Position of Windings. — It makes no appreciable difference upon what portion of the core any particular turn is wound, nor does the fact that some of the turns may be close to the iron and others at a greater distance from it, appreciably modify the result, within the limits of the dimensions of the magnets used in telegraphy. 186. The Helix or Coil. — Upon the cylindrical cores of the magnet are fixed flanges or collars D D (Fig. 69), of hard rubber or other like material, which, in connection with the cores, form spools or bobbins upon which- the magnetizing coil is wound in superposed concentric layers. The space E E, which is designed to contain the wire, has its boundary indicated by a dotted line. FIG. 70 Illustration of the Law of Diametrical Squares. wound within a space of given dimensions, such as the space E E, Fig. 69, is inversely in proportion to the square of the diameter of the wire. This will appear from the diagram Fig. 70, in which are shown within a space i in. square, the outlines of i wire i in. diame- Relation of Thickness and Length of Wire. 93 ter, 4 wires \ in. diameter, and 16 wires J in. diameter, all of which •occupy precisely the same area of cross-section in the spool. The number of turns which can be put within a given space is also inversely as the square of the diameter of the wire, measured to include its insulating covering.16 As the electrical resistance of a wire is •directly as its length and inversely as its sectional area or the square of its diameter (118), it will be obvious that the number of turns in the coil of any electro-magnet must have a direct and invariable relation to its resistance, and hence the resistance of a coil may be taken as a measure of the number of turns of wire it contains. This is •convenient in practice, inasmuch as the resistance is easily determined by proper apparatus, while it is not so easy to find the number of turns in a coil after it has been wound. It is for this reason, and not because the resistance in itself has anything to do with the matter, that it has become customary among telegraphists to classify electro-magnets by reference to their measured resistances. 18 A very convenient rule for calculating the windings of the coils of two different electro-magnets of the same type, but of different dimensions, is given by Sir William Thomson, and is as follows: Similar iron cores similarly wound with lengths of wire proportional to the squares of their linear dimensions will, when excited by equal currents, produce equal intensities of magnetic field at points similarly situated in with respect to them. Professor Silvanus Thompson has also pointed out as a corollary that similar electro-magnets of different dimensions must have ampere-turns proportional to their linear dimensions, if they are to be magnetized up to an equal degree of ;saturation. per wire most used for the helices of galvanometers and telegraphic magnets. It is taken from one calculated by George B. Prescott, Jr., on the basis of Dr. Matthiessen's standard, viz. : different makers. The figures in the table refer to a single covering of silk. For a double-covered wire, add the difference between the figures in the second and third columns to the figures in the third column. 189. Thickness of Spaces between Turns of Wire.— The thickness of a covered wire or of its covering cannot be correctly determined by the process of direct measurement by a gauge (192), though it may be approximated by the careful use of such a micrometer caliper as that shown in Fig. 73. The most accurate method is to measure the longitudinal space occupied by a number of turns when closely wound upon a mandril or small cylinder ; divide this length by the number of turns, and from the quotient subtract the diameter of the copper wire measured by the micrometer caliper, and divide the result by 2, which will give the thickness of the covering.19 18 Electrician and Elec. Eng., iv. 217. 19 Helices made of bare copper wire, accurately wound by machinery in such a manner as to leave an air-space of i mil. (.001 in.) between each two adjacent turns, and having the successive layers separated by thin paper, have been much used in the United Slates with very satisfactory results. Instruments for Gauging Wire. 190. American Standard Wire Gauge. — Great confusion formerly existed, both in this and other countries, in respect to wire gauges, designated as the custom is by progressive numbers, there having been almost as many so-called standards as there were different manufacturers. The Brown & Sharpe Manufacturing Co., of Providence, R. I., some years since established a gauge in which the actual thickness of wires designated by successive numbers is made to diminish in a true geometrical progression. Under the name of the American gauge^ this has now become the generally accepted standard in this country among manufacturers of copper, brass, and german-silver wires, and it is this gauge that has been used in this work, unless otherwise specified. This standard has not as yet been generally accepted by manufacturers of iron wires, such as are used for telegraph lines. having spools or bobbins of equal capacity, and wind them with three different gauges of wire (for the sake of illustration, say the three sizes shown in Fig. 69) ; for each turn of a wire i in. in diameter we should have 4 turns of the \ in. and 16 turns of the \ in. wire. Now, if we send a current of i ampere through the thinner wire, one of 4 amperes through the medium-sized wire, and one of 16 amperes through the thick wire, we should find, in accordance with the principle stated in (176), that the magnetic force would be precisely equal in each of the three magnets. This would be true, notwithstanding the difference in strength of current, and of thickness, length, and resistance in the wire of the helix, because the number of ampere-turns is the same in each case. We have : A thorough understanding of this principle enables the electrician to determine the winding of his electro-magnet so as to correspond with the characteristics of the current by which it is intended to be worked ; for it will be readily seen that to produce a given intensity of the magnetic field, upon which all magnetic effects depend, the number of turns in the coil must be in inverse proportion to the number of amperes of current traversing the magnetizing coil. 194. Spectrum of the Electro-Magnet. — The action of the magnetic forces in such an electro-magnet as that delineated in Fig. 68 can best be studied by means of magnetic spectra, produced in the manner described in (68). Fig. 74 shows the spectrum of such a magnet, when the current through the coils is barelv sufficient to a mass of soft iron, such as the core of an electro-magnet, becomes enveloped in a magnetic field (169), an appreciable time elapses before it acquires the maximum intensity of magnetization which the field is capable of producing. On the other hand, when the iron is withdrawn from the field, or, what is the same thing, the field is withdrawn from the iron, the latter does not lose its magnetism instantaneously ; the magnetism falls off progressively in the same way in which it increased, and in almost every case some small quantity of magnetism will remain for some time, and possibly forever, after the separation of the iron from the field. This is termed remanent, or more commonly residual magnetism^ In some brands of cold-blast charcoal iron, when carefully annealed, such as Norwegian, Swedish, and Lowmoor iron, scarcely a trace of residual magnetism remains, and these irons are therefore preferred in the manufacture of magnet cores. Experiment has also shown that the shape of the core is no less important than its quality, and that quickness of action and freedom from residual magnetism may be best secured by making the cores as short as possible. These conditions are sufficiently fulfilled for ordinary purposes in the proportions of the magnet shown in Fig. 68, p. 91. 196. Induction of a Current upon Itself. — It has been stated (151) that an electric current traversing a conductor has the capacity of inducing a temporary current in a neighboring conductor. This phenomenon manifests itself in the coils of an electro-magnet in such a way that its effects are added to those of hysteresis (with which, however, they must not be confounded), so as to still further delay the magnetization and demagnetization of the iron core. These inductive effects make their appearance when the inducing current is either increased or diminished, but not rection of the inducing current in the wire A, and of the induced current in the wire B), but it may also exercise an inductive action upon the conductor in which it flows. In a wire coiled back upon itself, as in Fig. 77, an increasing current, flowing in the direction of the arrow between A and B, tends to induce a current in the opposite direction between C and D, which opposes the original current and delays its increase. If. ^ 77^^oi Seif-mon the other hand, the current between A duction m Coiled Conductor. 20 This effect was carefully studied some years since by Professor J. A. Ewing, who gave it the name of hysteresis, from a Greek word signifying " to lag behind," denning it as the lagging behind of changes in magnetic intensity to changes in magnetizing force. EWING : Researches in Magnetism, Philosophical Trans. Royal Soc., 1885. and B is diminishing, it tends to induce a current between C and D in the same direction as itself, and this prolongs the duration of the original current by delaying its decrease. As the wire in the coil of an electro-magnet is placed under the same conditions as the wire in Fig. 77, it is clear that both the magnetization and the demagnetization of its core will be retarded, first, by the self-induction of the coil, and second, by the effects of hysteresis in the iron. Besides this, the presence of the iron enormously increases the normal selfinduction, because the rising magnetization induces an opposing e. m.f. in the wire, upon the principle explained in (78), for it will obviously make no difference whether the field be created about the wire, or whether it be moved thither from some other point in space. The sum total of these effects is termed magnetic inertia. 197. Magnet Cores must not be Hardened.— After the core of a magnet has been annealed, it is very important that it should be left black, and no attempt be made to brighten it up. If it be filed, or touched ever so little with a cutting tool, it will be slightly hardened, and will be certain to show traces of residual magnetism (195) when put to service. For the same reason the armature of an electro-magnet should never be permitted to hammer upon its poles. 198. Effect of Self-induction and Hysteresis in Telegraph Magnets. — A series of experiments conducted by an officer of the U. S. Coast Survey has shown that the average period of time required for a well-proportioned telegraph magnet to release its armature, varies from 0.003 second, with maximum tension of retracting spring, to 0.033 witn minimum tension.21 The best working adjustment would be midway between these values, that is to say, 0.015 second. 199. Other Indirect Causes of Retardation in ElectroMagnets. — It has been stated that the magnetism developed in a given mass of iron depends solely upon two factors, the quantity of current, and the number of turns of the conducting circuit around the iron (176). It has furthermore been stated that the quantity oi current traversing a circuit in turn depends solely upon the e. m.j of the generator and the resistance of the conductor (127). But ex periment shows that in respect to quickness of magnetization and demagnetization, irrespective of absolute intensity of magnetism, il makes a very great difference whether an exciting current of equal quantity has been produced by a low e. m.f, acting through a small resistance, or by a high e. m.f. acting through a proportionately great resistance ; the magnetic actions in the latter case being far more rapid than in the former. This effect is due to the greater resistance, which in the latter case has to be overcome by the currents of self-induction set up in the coils of the magnet, which, as we have seen (196), tend, in proportion to their strength, to give rise to mag* netic inertia, by delaying both the magnetization and demagnetization of the iron core. The e. m. f. which tends to set up these opposing currents is necessarily of equal value in either case, as it is determined by the quantity of current in the coil and the intensity of magnetism in the core : but the resistance the currents are obliged to overcome is much greater in the second case than in the first, and therefore the currents themselves are in fact very much weaker, and their retarding effect is diminished in the same proportion. This fact has an important bearing upon the working of fast-speed instruments. 200. Electro-Magnet with Polarized Armature.— If the armature, like the core of the magnet, is of soft iron, and placed parallel to the polar surfaces, as in Figs. 69 and 75, the action is simply one of attraction, irrespective of the polarity of the magnet, and independent of the direction of the exciting current. Jf, however, the armature itself be a permanent magnet (63), the direction in which it tends to move will depend upon the polarity of the electro-magnet, which in turn is determined by the direction of the exciting current. 201. In illustration of this, let the electro-magnet of Fig. 78 be provided with a polarized armature, consisting of a small permanent magnet n s, which is pivoted at one end to the yoke of the electromagnet, while its opposite end is free to play back and forth between the poles of the N S of the electro-magnet. When the current passes in one direction, as, for example, in Fig. 78, the n pole of the polarized armature is attracted by the unlike pole S of the electromagnet, and at the same time repelled by its similar pole ; but upon the reversal of the direction of the exciting current, the polarity of the electro-magnet is likewise reversed, and the polarized armature is now attracted to the opposite side, as shown in Fig. 79. It is obvious, therefore, that the direction of the movement of the polarized armature depends solely upon the direction of the current, and not upon its strength. There is, therefore, an important difference between the operation of a permanently magnetic or polarized armature and a non-polarized or neutral armature. 202. Combinations of Permanent and Electro-Magnets. — Various mechanical combinations of electro and permanent magnets have been made, all of which involve essentially the same principles as the simple apparatus figured above, and by which a like effect is produced. The polarization is not necessarily confined to the armature, as similar results may be obtained by constructing the apparatus in various ways, provided that some one portion of it is polarized and another portion non-polarized. This principle is of special value in multiple telegraphy (321). 203. It has heretofore been explained (30) that an electric circuit consists of an endless series or chain of conductors. That portion of the circuit which is situated between the terminals or poles, and within the generator, is called the internal circuit, and its resistance is the internal resistance of the generator ; the chain of conductors which joins the poles outside of the generator is called the external circuit, and its resistance is the external resistance of the circuit. 204. The essential characteristics of every electric circuit are the same, although such a circuit may vary in length from a few inches to thousands of miles. It may be supplied with electricity from a single source, or from two or more sources situated at different points, and it may include a single receiving and transmitting instrument, or a large number of such instruments situated at different points along its course. But in every case, without regard to the length of the circuit, the time actually occupied in the transmission of the electric impulses, although not inappreciable, may be regarded, for all practical purposes of ordinary telegraphy, as instantaneous. 205. Telegraphic Circuits. — A telegraphic circuit is made up of the following parts : (i) the generators, either batteries or dynamoelectric machines; (2) the line conductors; (3) the earth, which is usually employed as a substitute for the return line wire from the distant station ; and (4) the instruments for transmitting and receiving signals. 206. Open and Closed Circuits. — There are two ways in which a telegraphic circuit may be arranged for the transmission of signals, (i) The generator may be kept normally in connection with the line, thereby causing a constant current to traverse the circuit, and signals may be transmitted by alternately breaking and closing the circuit ; or (2) the generator may be normally disconnected from the line, and signals may be transmitted by alternately inserting the generator into and withdrawing it from the circuit, so as to cause a current to flow for the desired period of time to form the signals. Drawings of Electric Apparatus. 103 The first is called, in a general way, the closed-circuit and the second the open-circuit system. In other countries than North America one or the other of the above-mentioned systems is almost invariably employed, but the system in universal use in our own country, although usually spoken of as a closed-circuit system, may more properly be regarded as a compromise between the two, possessing some of the characteristics of each. As in the true closed-circuit system, the current constantly traverses the line when no work is being done, but signals are transmitted, not by interruptions of this current, but by first interrupting it at the sending point, and then transmitting the signals by closing the circuit at properly timed intervals, thus permitting the current from the generator to traverse the line and the receiving instrument, as in the open-circuit system. 207. Drawings of Electric Apparatus. — There are three principal methods of representing organizations of electrical apparatus: (i) by perspective drawings, (2) by geometrical drawings, and (3) by diagrams. Perspective drawings are ordinary pictorial illustrations. They show the appearance of the apparatus, but, as a rule, are not well adapted to convey to the mind a clear idea of its principle and mode of operation. Geometrical or working drawings consist of plans, elevations, or sections, drawn to a scale, which may represent the whole or some part of the apparatus. They usually exhibit all the constructional details, whether essential to the operation of the apparatus or not, and while indispensable to the workshop, are ordinarily of little use for purposes of explanation. Figs. 35 and 36 (pp. 46, 47) are examples of-geometrical drawings. Diagrams exhibit the apparatus, circuits, and connections, not in their actual form and proportions, but in such a conventional manner as will most clearly illustrate the principle of the apparatus and its mode of operation. Diagrams ought not to be encumbered with details which are merely constructional, and therefore unessential. The advantages of a uniform and well-understood system for the conventional representation of electrical apparatus and circuits will be apparent. 208. Conventional Representations of Circuits and Apparatus.— In the following paragraphs are briefly described various component parts of telegraphic circuits, with the symbolical representations which, by general consent, have been adopted to represent them, and the apparatus employed in connection with them. 209. The Earth as an Electrical Conductor. — The earth, being composed of a vast mass of inorganic material, mostly of a porous character, and permeated throughout by water, forms an excellent conductor of electricity, and it is almost invariably employed in this capacity as a part of every telegraphic circuit. While its specific conductivity, as will appear from the table (p. 57), is much lower than that of metallic substances, yet this is abundantly compensated for by the enormous area of its cross-section. vanized iron are cheaperr and are often used instead of copper ; they appear to answer the purpose perfectly well. The ground-plates should be buried in moist earth in a vertical position. In many cases an available substitute may be found by attaching the terminal of the line, by soldering or otherwise, to a pipe which forms a part of an extensive network of gas or water conductors buried in the earth, the large surface of which insures a most excellent conducting connection. It is advisable, wherever possible, to attach the wire to both gas and water pipes. When the wires are thus connected to a pipe, certain precautions are necessary to be observed, especially that of soldering the wire to the pipe outside the meter. The connecting wire which is soldered to the ground-plate should be coated with insulating material, to prevent corrosion of the wire by the electrolytic action which might otherwise take place (27). If circumstances render it necessary to bury a ground-plate in badly-conducting soil, as, for instance, where it is rocky, sandy, or gravelly, without sufficient moisture, a pit should be dug, and filled with scrap tin or other waste metals laid in contact with the plate, and the surface drainage and discharge from water pipes should be led into it. 211. Advantages of the Earth Circuit.— Several important advantages arise from the use of the earth in telegraphy as a part of the circuit. The entire cost of the return wire and its insulation is saved, while at the same time the resistance of the circuit is reduced nearly one-half. On the other hand, the inclusion of the earth materially increases the difficulty of maintaining an efficient condition of insulation throughout the circuit (219). sufficiently good ground connection. An instance was observed some years since by the author in which it was impossible to secure a ground connection which would not offer an abnormally great resistance to the flow of the current. This was in the anthracite coal regions of Pennsylvania. Professor Moses G. Farmer informs him that he has met with the same difficulty in some places in the mountainous districts of New Hampshire and Vermont, on the lines between Boston and Montreal. 212. The Open Circuit. — A telegraph line arranged upon the open-circuit plan is illustrated in Fig. 81. Two terminal stations are shown, each having a battery, a transmitting key, and a receiving instrument. The circuit of the line divides at each key into two branches, of which only one can be closed at the same time. One branch includes the battery only, and the other the receiving instrument only. The latter branch is normally in connection with the circuit of the line. If a signal is to be sent, the key is depressed by the operator, so as to establish the connection of the line with the battery, having first broken it with the instrument. A current from the battery will now flow through the key and over the line in the direction indicated by the arrows to the other station, where it passes through the instrument contact of the key and through the receiving instrument, avoiding the battery, and thence back through the groundplate and the intervening mass of earth to the opposite pole of the battery at the sending station, thus completing the circuit. In this arrangement, therefore, each station transmits signals by inserting its own battery at timed intervals into a circuit of conductors which is already complete. 213. The Closed Circuit.— Fig. 82 illustrates the closed-circuit plan, properly so called. In this the cells of the battery or batteries are always in the line, and the circuit passes normally through the rear or breaking contact of the keys, and through the receiving instruments at both stations. By depressing the key at either station (as shown at the right hand in Fig. 82), the current of the entire line is interrupted, and a signal is simultaneously given upon both receiving instruments by the falling off of the armatures of the electromagnets of the receiving instruments. which is the standard arrangement employed in the United States, Canada, and Mexico. It differs from the last described in that the circuit does not normally pass through the key at all, but through a Position of Battery in Closed Circuit. 109 switch or special circuit-closer beside it, which, as a matter of convenience, is in practice usually mounted upon the key, though shown separately in the diagram, as it is sometimes arranged in fact. To transmit a signal according to this plan, the circuit of the line is first broken by opening the switch, and the signals are then made by depressing the key so as to close the circuit at timed intervals upon its front contact-point. As in the last case, the alternate opening and closing of the circuit at one station affects alike the receiving instruments at all stations. 215. Comparative Advantages of the Different Plans.— Each of the foregoing plans of organization of a telegraphic circuit has certain peculiar advantages and disadvantages, which will be further considered hereafter. It may, however, be stated here, that one principal advantage of the closed-circuit systems is that a great number of stations may be placed upon a single line without materially interfering with each other, and may be equipped with the simplest of apparatus, all the batteries being placed at the terminal stations, where they can more conveniently receive skilled and sufficient attention. 216. Position of Battery in Closed Circuit.— While it is usual in a closed-circuit system to place a battery at each end of the line, as shown in Figs. 82 and 83, it is by no means an essential requirement. Comparatively short lines of say 25 or even 50 miles in length are often supplied with a battery only at one end, while very long lines are occasionally provided with an intermediate battery midway between the terminal batteries. In rare instances a battery is placed in the middle of the line only. The arrangement shown in Figs. 82 and 83 is considered preferable to any other? unless for exceptional reasons which may apply to some particular case. 217. General Considerations respecting Telegraphic Circuits. — In all telegraphic circuits (with the exception of those of direct working electro-chemical systems, which do not come within the scope of this work), the object sought to be obtained is to produce signals at a distant station by alternately closing and breaking the circuit at the home station, so as to alternately magnetize and demagnetize the electro-magnet of the receiving instrument at the distant station. It is therefore primarily essential that the current traversing the coils of the distant electro-magnet should be of sufficient quantity to cause the latter to attract its armature with certainty when the circuit is closed, while, on the other hand, it should be insufficient to maintain the armature in proximity to the magnet against the force of the antagonistic spring, or other retracting device, when the circuit is broken. This result is most perfectly attained when the maximum current going through the helix of the receiving magnet is sufficient to cause the armature to be promptly attracted^ and the minimum current is zero, or no current. But upon lines of ordinary length, exposed to unavoidable atmospheric influences,, these conditions are usually impossible of fulfillment. The more nearly this ideal condition can be approximated to, the better are the results. It can only be fully realized upon a line of which the insulation is absolutely perfect. 218. Relation of Conductivity to Insulation Resistance^ — Practically the end aimed at in all telegraphic circuits should be to make the resistance of the conductor as small as possible, and the resistance of the insulation as great as possible. Therefore, in constructing a telegraph line, it is important to employ the best possible conductor which the necessary limitations of cost will permit, and to prevent the escape of the current in undesired directions by the use of the most efficient insulators. 219. Effect of Imperfect Insulation. — The deleterious effects of imperfect insulation upon the operation of a telegraphic circuit will be understood by reference to Fig. 84, which represents FIG. 84. Effects of Imperfect Insulation. two stations, A and B, connected by a telegraph line, the earth being used as a return conductor. If we suppose the line to be provided with a battery at station A only, the current from its positive pole flows along the line toward B, as indicated by the arrows, but a small portion of this current escapes from the line through or across the defective insulators at every successive support. These currents of leakage find their way directly into the earth in the direction indicated by the arrows, returning to the negative pole of the battery, at A, without going through the instrument at B at all. Every imperfectly insulated point of support therefore constitutes Telegraphic Conductors. 1 1 1 a branch circuit (140), and causes the current to divide in proportion to the total resistance of the support and its insulator as compared with the joint resistance of that portion of the line and the branch circuits beyond the point of division. It is evident that the greater the resistance, jointly and severally, of the insulators, and the less the resistance of the line conductor, the greater will be the percentage of the total quantity of current entering the line at A which will reach the instrument at B. But as some portion of the total current must escape from the line at every point of support, it will come to pass, unless the line be perfectly insulated, that at some distance from the initial point, depending both upon the conductivity and the insulation of the line, so large a proportion of the current will have escaped from the line through the supports to the earth, that the remainder will be insufficient to produce any appreciable effect upon the receiving instrument. 220. Working Efficiency of Telegraphic Circuit. — The working efficiency of a telegraphic circuit is therefore determined by the ratio between the resistance of the conductor and the resistance of the insulator. If the total resistance of the conductor be divided by the total resistance of the whole number of insulators — that is to say, by their joint resistance — the quotient will represent fas. efficiency of the circuit. The smaller this quotient, the higher the efficiency (243). 221. Telegraphic Conductors.- — The wires used for telegraphic conductors are almost invariably either of iron or of copper. Iron wires were formerly exclusively used for outside or aerial lines. Since 1885 these have largely been superseded, in all new work, by wires of hard copper. Copper wires are invariably employed for interior work, which term comprises the wires within buildings and about the apparatus. They are also employed for all subterranean and submarine conductors. The table on page 112 gives the dimensions, weight, conductivity, resistance, etc., of the sizes of iron and copper wires most generally employed as telegraphic conductors. 222. Iron AAfires. — Until within a few years the size of iron wire most commonly employed in the United States has been that known as No. 9, which probably still constitutes something like onehalf of the total mileage of the country. Nos. 8, 6, and 4 are larger sizes which have come into use, especially since 1875. No. 4 is the largest iron wire used in this country, and No. 10 is the smallest used in the public telegraph service. These numbers refer to the so-called Birmingham gauge, and not to the American (190). See Fig- 85- and are then soldered, to insure good metallic connection and to exclude moisture. The usual number of posts or supports in the United States is from 30 to 40 per mile. The smaller the number of posts the less the leakage from imperfect insulation and the less the cost. 223. Office \Vires. — The copper wires used for interior wiring should generally be of No. 16 American gauge or thicker, and well covered with insulating material. If the location is perfectly dry and the number of wires is not very great, a coating of cotton braid, double, and saturated with paraffin or wax, answers very well. If there is any danger of exposure to dampness, some of the higher grades of insulated wire, most of which aie known by special trade names, such as Kerite, Okonite, etc., are to be preferred. Specimens of some of the most useful varieties of these office wires^ as they are called, are illustrated in Fig. 87. The great number of varieties of insulation now in the market offers a wide scope for selection, both in quality and cost. 224. Copper Line W^ires. — About the year 1880 it was discovered that copper wire, drawn by a process which gave it greatly increased tensile strength without materially impairing its conducting qualities, could be had in the market, and as a result many lines have since been built with this wire, with the most satisfactory results. At the prevailing prices of copper and iron, the cost of the copper line is little if any more, all things considered, than that of an iron line of equivalent conducting capacity ; while, if very great conductivity is desired, it is absolutely necessary to resort to copper, as an 225. Telegraphic Line Insulators. — Telegraphic lines are carried through the country supported usually upon wooden posts, but occasionally upon other structures, such as buildings, bridges, etc. These supports are separated at intervals, varying on different lines from 150 to 300 feet, or from 20 to 40 per statute mile. At each point of support each wire is affixed to an insulator, the office of which is to prevent, so far as possible, the escape of the current from the line through the support to the earth, in its endeavor to return to the battery by the shortest route (219). Much ingenuity has been expended, and, it must be confessed, with very unsatisfactory results, to devise an insulator which shall be capable of per manently maintaining its non-conducting properties during continued wet weather. The insulator which is in most general use in North America is an inverted cup of pressed glass, mounted upon an oak pin which forms its support, as in Fig. 87, the line being secured to its side by a tie wire which lies in a circumferential groove surrounding the insulator. The ordinary glass insulator is a device which has little to recommend it except its cheapness. Nevertheless, there is much to choose between the different forms in which the glass insulator is to be had. Two models in common use are shown in diametrical cross-section in Figs. 88 and 89. The figures are one-half the actual size, and the measurements are given in the drawings. sulator.— The glass of which these insulators are composed is a substance which, as regards its body, is a sufficiently good non-conductor under most circumstances ; but unfortunately, in rainy and damp weather, especially when the temperature of the atmosphere is rising, its entire surface becomes coated with a continuous film of moisture. This watery film forms a conductor at Tested by this rule, it will FIG. 89. Western Union Standard Insulator. be seen that the pattern illustrated in Fig. 89 must be better than that shown in Fig. 88, as in the first the actual linear distance from the conducting wire to the sup- porting pin (as shown by the heavy outline) measures 5.5 in., while in the second it is only 4.3 in. It is true that the insulator, Fig. 88, is somewhat smaller in diameter than the other, which is so far an advantage ; but, on the other hand, a comparatively great part of the insulating length of the latter is underneath, where it is well protected from the direct action of the falling rain. 228. The Hard-Rubber Insulator. — Another variety of line insulator more or less in use is the hard-rubber, which consists of a malleable iron hook for clamping and holding the wire, covered with a mass of vulcanized rubber, in cylindrical form, with a thread cut upon its exterior, which is screwed into a block, wooden arm, or other convenient support, as shown in Fig. 90. The non-conducting properties of vulcanized rubber have been found to deteriorate very rapidly on the surface by exposure to the weather, and hence this form of insulator is now but little used except for short lines in cities, for which it possesses some advantages by reason of its small size, light weight, and general con- ing and clamping the wire. The surface of the cement, both within and without the glass bottle, is coated with paraffin having a melting-point of about 145° Fahr. The iron shell is inserted into a hole bored in the under side of a cross-arm, which last is bolted transversely to the upright post. 230. The Porcelain Insulator.— The insulator shown in Fig. 92 is made in great perfection in Germany, and is extensively used in Europe, Asia, and South America, but not in the United States. All things considered, it is perhaps the most efficient insulator now the socket is packed with hemp and linseed oil when the insulator is put on. A straight iron bolt with a shoulder is used with a cross-arm, secured by a nut screwed on the under side of the arm. 231. Defective Insulation of American Lines.— The most serious defect in the construction of the telegraphs of the United States is unquestionably the character of the insulation. Very few of the lines exhibit any material improvement in this particular over those constructed forty years ago. It is true that the working efficiency of the more important lines has been greatly increased during the period which has since elapsed, but the improvement is due almost wholly to the use of conductors of lower resistance, and to the substitution of powerful dynamo-electric machines in the large terminal stations for the voltaic batteries formerly used. The efficiency of the less important lines is no greater, and, in many instances, not as great, as it was twenty years since. The insulators almost universally employed, as pointed out in (227), are deficient both in material and in design. In addition to their inherent defects, there are usually a considerable proportion of cracked or broken ones, which the most vigilant inspection cannot wholly prevent. The of the glass insulators on its lines require renewal yearly.1 232. Effects of Climate' upon Insulation. — The combined effect of dirt and moisture upon the surface of insulators is very deleterious. Ordinary insulators in this country are affected proportionally as the air becomes charged with moisture. In the winter months this often occurs, and is notably the case when the ground is covered with melting snow, and the rain is from the south. Northeast storms begin with the wind from the northeast. Usually the wind changes to the east and south, and finally it clears up with the wind from the west and northwest. During the portion of the storm when the wind is from the southeast and south, the air is charged with moisture to its full capacity, or total saturation. It is during this time that the ordinary glass insulator is most affected. When the storm is accompanied by the wind changing in the other direction, that is, from northeast to north, and finally to northwest, the insulation is much less affected, because the atmosphere is seldom charged to over 80 per cent, of full saturation. DAVID BROOKS : The Telegrapher, xi. 73. Mr. Brooks, who has devoted much attention to the investigation of questions relating to the insulation of telegraph lines, has remarked that in cities in which the fuel principally used is anthracite coal, the gas which is formed and escapes into the atmosphere produces a very deleterious effect upon the surface of glass insulators. He found while during rain, insulators in the country, in regions free from smoke, give a resistance of 60 to 100 megohms per insulator, in the city under the same conditions of weather, the resistance falls as low as 4 to 6 megohms per insulator. He instances a line in the city of Pittsburgh, a locality formerly famous for the quantity of bituminous coal-smoke which pervaded its atmosphere, where glass insulators which had been exposed on the line less than two years were so coated with soot that they gave a measured resistance of less than i megohm per insulator. Moses G. Farmer, who is also excellent authority in such matters, says : " I presume from long experience and many careful tests, made in the worst weather, that 9 megohms will be above the average value of three-quarters of the insulators used in this country, in the Middle and Northern States, in long-continued heavy storms."2 A very fair idea of the comparative efficiency of some of the different insulators referred to in this chapter may be gathered from the report of a test of five years duration, extending from March I, 1868, to March i, 1873. The different varieties^of insulators were exposed in sets of 10, the mean resistance of this number being taken in each test. The total number of 4. Brooks' Paraffin (like Fig. 91). 5. Boston screw-glass (nearly like Fig. 87, but with internal screw-thread), exposed I year 234. Distribution of Potentials in Telegraphic Circuits. —The manner in which the varying potentials at points in an electric circuit may be graphically delineated in accordance with Ohm's law, has been explained in (145). The application of this method of illustration to the specific conditions of a telegraphic circuit is instructive, as it enables the student to form, as it were, a mental picture of the electrical condition of every portion of the line when in normal condition, or when affected by leakage arising from faults and defective insulation. In pointing out the application of this graphic method of representation, to a telegraphic circuit, it will be convenient in the first instance to assume the circuit to be perfectly insulated. 235. Potentials in Perfectly Insulated Circuit.— If a battery of 100 gravity cells in series be connected to a perfectly insulated line of say 100 miles in length, open at the distant end, as shown in Fig. 93, the line will acquire a potential throughout its entire length, of 100 volts, which is equal to the e. m. /. of the battery. This will be the case, however great may be the length of the line. 236. If now the distant end of the line be connected to the earth, as in Fig. 94, a positive current will traverse the line. This will not affect the e. m. f. of the battery, which remains 100 volts as Potentials in Perfectly Insulated Circuit. 121 before, but the distribution of potentials will be changed in every part of the circuit. The distant end of the line becomes o or zero, being the same as the assumed potential of the earth with which it is directly connected, and from this point it rises gradually and uniformly along the line to the terminal or pole of the battery; at which point, as we shall hereafter see, it will be something less than 100 volts. Having ascertained the actual potential at this or any other point on the line, it may readily be calculated for any other point, for in a circuit of uniform resistance, the potential varies directly as the distance from the zero end of the line (145). Thus if it is known to be 80 volts at 100 miles, it must be 40 volts at 50 miles, Positive and Negative Potentials in same Circuit. 20 volts at 25 miles, and so on, the different potentials at different points being represented by the sloping dotted line in Fig. 94. The potential which has been referred to is positive, but the law is of course the same with a negative potential, which is a potential less than that of the earth. An example of this is given in Fig. 95, which represents two parallel insulated lines each 100 miles in length, looped together at the distant ends. The middle of the battery c z is connected to the earth ; and this point, therefore, acquires a potential of zero. The upper half of the battery imparts a positive potential to the upper line, and its lower half a negative potential to the lower line. The potential falls regularly from the c pole of the battery to o, and rises regularly from the z pole of the battery to o. If a wire were connected between the earth and any point along the length of the upper line, a current would flow from the line to the earth, the quantity of which, by Ohm's law, would be in proportion to the potential at that point. If the wire were connected in the same way to any point on the lower or negative line, a current would in like manner flow from the earth to the line. In the illustration given, it will be observed that there are two points of zero potential where it changes from positive to negative, one in the middle of the battery and the other at the point where the lines are looped. This is the same as the distribution of potentials in Fig. 57, p. 71, and illustrates the distribution on a telegraph line like that represented in Figs. 82 and 83, p. 108, in which there is a closed circuit with a battery at each end, these constituting electrically one battery united with the earth at its centre precisely as in Fig. 95. Fig. 96 represents a line of 100 miles connected with a battery having an. e. m. f. of 100 volts, the distant end of the line being to earth. If" the free pole of a second battery, with its similar pole to the earth, be now connected at any point to this line through a galvanometer, each battery will tend to send a current to the line. If the batteries are of equal potential, and attached at the same point, the needle will be deflected, say to the right. If now the number of cells and consequently the e. m. f. of the second battery be gradually diminished, a point will soon be reached at which no current will traverse the galvanometer, and its needle will stand at zero. When Determination of Potential by Calculation. 123 this condition exists, the e. m.f. of the second battery is equivalent to the potential of the line at the point of attachment. The e. m. f. of the auxiliary battery will always be less than that of the principal battery, even when connected quite close to it ; while as we recede from the battery, the number of cells or the e. m. f. required to maintain the needle at zero will gradually diminish, till, near the remote end, even a single cell will suffice to send a current into the line, because the potential at that point is approximately zero. 236. Determination of Potential by Calculation.— The diagram, Fig. 97, illustrates the manner in which the potential at any point on a perfectly insulated line may be calculated, when the FIG. 97. Calculation of Potential from e. m. f. of Battery. e. m. f. of the battery is known. Let A B represent a battery of say 100 volts, and let B C be an insulated line of any length. Let the line A B be drawn of such a length as to be in proportion to the internal resistance of the battery (131), and let the length BC correspond, in the same proportion, to the resistance of the line. Let the height of the line A D represent the e. m.f. of the battery. The height of the line B E will now represent the potential of the line at its junction with the battery, while the height of a vertical line, or ordinate, F G, will represent the potential at any other point, as, for instance, F. The potential at any point in the line may be calculated by the following rule : As the aggregate resistance of the line and battery is to the resistance C F, measured from the distant end of the line, so is the e. m.f. of the battery to the potential at a given point (as F) ; or, A C : F C : : A D : F G. 237. Potentials within the Battery.— The distribution of potentials within the battery follows precisely the same law. Fig. 98 shows a battery of 4 cells connected to a line of infinite resistance — that is, having its distant end open. The potentials are indicated by the upper dotted line, and are, under these conditions, equal to the e. m.f. at each point. The potential rises approximately i volt at each surface of contact between the zinc and the exciting solution, the same resistance as itself; that is, the resistances of the internal and the external circuits of the battery (203) are equal. The potential at the end of the line, instead of being 4 volts, is now o, or zero. FIG. 99. Battery Potentials with Closed Circuit. The potential at other points in the circuit, measured in volts, is shown in the diagram by corresponding figures. It will be observed that the potential falls in the liquid portion of each cell in proportion to the resistance, in the same way that it does on the line. 239- Fig. 100 shows the. same battery short-circuited, that is, connected at each end with the earth by a wire of no appreciable resistance. The potential at both ends of the battery being now main- tained at zero, the potential rises within each cell, as in the previous examples, the maximum point of potential being at the contact of the zinc plate of each cell with the liquid, irrespective of the number of proportion to the resistance of the liquid. 240. Fig. 101 shows a single cell, short-circuited by a wire a b, which is supposed to be so thick and so connected to the earth as to maintain both plates z c at a potential of zero. In this case the difference of potential in the circuit exists only within the liquid, as shown by the diagonal dotted line. In all these varied examples we find the distribution of potentials conforming strictly to Ohm's law as laid down and illustrated in Chapter V. of this work.3 241. Potentials in Imperfectly Insulated Circuit. — The distribution of potentials in a perfectly insulated circuit has now been explained, but, as a matter of fact, no telegraphic circuit is ever perfectly insulated, and in wet and unfavorable weather the potentials is materially modified. 9 For the illustrations and explanations of the distribution of potentials in telegraphic circuits given in the foregoing paragraphs (234 to 240), the author desires to acknowledge his indebtedness to LATIMER CLARK'S Electrical Measurement^ pp. 14-23 ; one of the very best of the early works on practical telegraphy, but unfortunately long since out of print. In Fig. 102, let A B represent a telegraphic line, connected at A to the pole of a generator, the e. m. f. of which produces at that point a potential represented by the perpendicular A F. If there is situated at b an escape through an imperfect conductor of known resistance, the fall of potential between F and b\ and between b' and B, may be determined, provided the resistance of the line, A b and b B is known, inasmuch as it will be in proportion to the resistance (144). It will be observed that the fall of potential is greater from A to b than from b to B. Fig. 103 shows the distribution with FIG. 103. Distribution of Potential on Leaky Line. two such points of escape of equal resistance at b and c. Fig. 104, in like manner, shows the distribution with five points of escape, bed ef. In each of these cases, the line at B being in direct connection with the earth, the potential at that point is zero. The difference of potential between each two successive points of escape becomes less and less as the distant extremity of the line is approached, and hence it follows that the quantity or effective strength of current in the line progressively decreases at each point, but that the decrease becomes less and less rapid as the terminal station B is approached. In an ordinary telegraph line the number of points of escape are Effect of Imperfect Insulation upon Current. 1 2 7 very numerous, being necessarily equal in number to the points of support, and hence the line of potential, F B, becomes a polygon of a corresponding number of sides, or in fact a regular curve. In Fig. 104, therefore, if the potential at the initial point of the line A is assumed at 100 volts, we might find, for example, at successive points, &' c' d' e'f, the following potentials, with a perfectly insulated and with a leaky line : normal straight line. 242. Effect of Imperfect Insulation upon Flow of Current.— The effect of imperfect insulation upon the line, whether general or special, is to largely reduce the resistance of the line, and proportionately increase the quantity of current drawn from the batteries by the line, so that the latter are exhausted much more rapidly when the weather is wet. Hence, in working on the closed circuit plan (213, 214), the line current is strongest in wet weather, except near the middle of the line ; but the variation or margin at any station, when the key is alternately opened and closed at another station, which constitutes the working efficiency of the line, is very much diminished. This variation or difference of course determines the available strength of signals. The effect of imperfect insulation upon the transmission of the current to a distant station has been referred to in (219). The various electrical characteristics of leaky lines have been found capable of determination by mathematical analysis. Since, however good the insulator may be, some small portion of the current escapes from the line over it down the post to the ground, it is manifest that if the line be long, the posts many, and the insulators very poor, a small portion only of the entering current may reach the far end of the line. The law which governs this may be thus enunciated : If the current upon the line near the battery be called the entering current, and that upon the distant end near where it enters the ground be called the arriving current. then the distance to which any stated fraction of the entering current will reach is proportioned directly to the square root of the conductivity of the wires, to the square root of the insulating power of the insulator, and inversely to the square root of the number of poles per mile used. MOSES G. FARMER: See Report on Telegraphic Apparatus at Paris Exposition (1867), by S. F. B. Morse, p. 69. 243. Resistance and Current in Leaky Lines. — When the average resistance of each insulator is known, it is easy to compute the actual insulation of the line per mile, or other unit of length. It is only necessary to divide the resistance of a single insulator by the number of insulators, inasmuch as it is simply a case of joint resistance (134). So also, when the resistance per mile of the conductor, and the resistance per mile of the insulation are both known, the apparent resistance of the conductor and of the insulation for any length of line may be determined. As the mathematical computations in this case are somewhat complex, a compilation of results •is given in convenient form for use, in Table X, p. 129. This table shows the apparent conductivity and insulation resistance (as measured from the terminal station) of various lengths of leaky line, from 100 to 2,500 units. The table also gives the percentage of any given entering current which will reach a terminal station located at various distances along the line. Many problems arising in the working of leaky lines may be conveniently solved by means of a table of this kind.4 In a well insulated line, the ratio of the conductivity to the insulation resistance ought to be as low as i to 80,000. The table is computed upon an assumed ratio of i to 10,000, which is probably as much as can be relied on in rain with the most carefully constructed glass-insulated lines in our climate, and may be regarded as fairly representative of the actual present practice. 244. Computation of Working Efficiency of Line. — As an example of the use of this table, suppose it be required to determine the comparative working efficiencies of the open-circuit (Fig. ST, p. 107) and the closed-circuit system (Fig. 83, p. 108) on a line of 200 miles in length, with a conductor of 10 ohms resistance per mile, supported upon 40 poles per mile, the wet-weather value of the insulators being 4 megohms each, and the resistance of the instruments 4 The author desires to express his obligations to Professor Moses G. Farmer for valued assistance in the preparation of this table. The formulas and methods of computation are discussed in the following named works : J. GAVARRET : Telegraphie Electrique, 376 ; E. E. BLAVIER : Telegraphic Electrique, ii. 447, 449 ; A. B. KEMPE : On the Leakage of Submarine Cables; Jour. Soc. Tel. Eng., iv. 90 ; H. R. KEMPE: Hand-book of Electrical Testing (3d ed.), 445. ioo ohms each. This would give for the line the same ratio of conductivity to insulation as that assumed in the table, viz: i : 10,000. The true conductivity resistance of the line from A to B (Fig. 105) is 2000 ohms. Assume the keys to be closed at both stations, the resistances of both instruments being alike, the e. m. f. of the two batteries also equal, and the internal resistance of the batteries to be so small, compared with that of the line, that it may be neglected. The first half of the line, from A to o, will be positive, and the other half, from o to B, negative. When sending to A, the key at B is alternately open and closed. With both keys closed, if a galvanoscope were to be connected between the point o and the earth, it would indicate no current, because the potential at o is zero. Hence the quantity of current going to line from the battery at A will be the same as if the line were connected to the ground in the middle — that is, at a point ioo miles from A. Assuming the e. m.f. of the battery to be TOO volts, the quantity of current entering the line at A, by Ohm's law, will be as follows : 245. This investigation shows that on a defectively insulated and leaky line, a material advantage is gained by dispensing with the battery at the receiving end of the line, and assembling it all at the sending end. In the case under consideration the difference in efficiency with the same line and instruments is as 548 to 293 in favor of the open circuit plan. With the battery constantly on the line, a computation may be made by the aid of the table, which will show that it makes no difference in the working efficiency, whether the battery be placed in equal amount at each terminal station, or whether it be all assembled in the middle of the line.5 246. Effect of Position of Fault.— The detrimental effect of a special defect in insulation or cause of escape, such as contact with the branch of a tree or a wet roof, is greatest when it is situated tion nearest the fault. 247. Best Position of Batteries in Circuit. — If the insulation of a line were perfect at all times, the position of the battery in the line would be immaterial. As all lines are ordinarily subject to more or less escape or leakage throughout their length, it is obviously not advisable, except upon comparatively short lines, to place all the battery at one end ; for in such case the signals will be received with much more difficulty at the station where the battery is situated, than at the opposite end of the line. The usual arrangement of a battery at each end is altogether preferable. 248. Intermingling of Currents on Different Lines. — The escape of the current through the insulators, poles, and cross-arms from one wire to another 'n wet -weather, known as cross-fire, is a far more prolific cause of interference in the working of lines than the mere leakage to ground. This effect is sometimes miscalled induction. Weather-cross is perhaps a more appropriate term. As electric currents always flow in greatest quantity in the direction of the least resistance, the tendency is for the currents to escape from a long circuit into a short one, or from a wire of higher into one of lower resistance. A simple escape to ground, if not too serious, may be overcome by the judicious application of increased battery-power ; but when transverse leakage or cross-fire exists between different wires running upon the same line of poles, any attempt to increase the battery, in order to improve the working of one wire, produces a detrimental effect upon the working of all the others parallel to it. Upon the occurrence of a sudden shower, the effects of cross-fire are usually manifested sooner than the escape to ground, because the horizontal cross-arms are wet and become partial conductors sooner than the vertical pole. 249. Remedy for Cross-Current.— This difficulty may be overcome by attaching a ground wire to each pole, the upper end of which is wrapped around the central portion of each arm. These wires act to intercept the currents of leakage passing from one wire to another, and to convey them to the earth. The battery may then be increased as much as desired on any one wire without interfering with the others. It is true that the pole, even when wet, has some little value as an insulator, which is lost by this appliance, but the gain in the other direction much more than compensates for it. 250. The results of defective insulation, in causing the mixture of currents between different wires on the same line of posts, are much more detrimental near the ends of the circuits than in the middle portions ; and as the terminals of the lines are almost invariably in large towns and cities where the insulation is usually much worse than elsewhere (232), the evil is aggravated accordingly. Much would be gained, therefore, by applying groundwires to the poles even for a distance of 25 miles out from each terminus. Arms as Insulators.— Tests made many years since to determine the average resistance, in wet weather, of the pin-and-glass insulator, the cross-arm, and the pole respectively, gave some interesting results. The tests were made 15 per cent. A test from New York to Boston between two wires, a and b, placed one above the other, as in Fig. 108, on insulators and brackets on opposite sides of the same pole, gave the following mileage insulation : From this it appears that the application of ground-wires to the poles would reduce the total insulation about 15 per cent., and weaken the signals perhaps 3 per cent. ; but, on the other hand, it would eliminate disturbing currents amounting to about 18 per cent, of the total strength of signals. 252. Tests of Resistance of Cross- Arms. — The following measurements were made of cross-arms taken down from pole-lines in New York City. They show the insulation resistance per mile of 40 arms : Best Method of Improving Efficiency. 135 These figures show in a striking manner the surface deterioration of glass insulators by exposure to the smoke and dirt of a large city. Cleaning them nearly tripled their insulating power.5 254. Importance of High Working Efficiency.— The importance of maintaining in telegraph lines as high a ratio of insulation to conductivity resistance as possible, is shown in a striking manner by the figures given in Table X. For example, suppose it were required to determine the effect of increasing the ratio of efficiency of a given circuit from i : 10,000, the basis on which the table is computed, to i : 20,000. This might be effected, either by doubling the resistance of the insulators, or by halving the resistance of the line ; that is, 8 megohm insulators might be used instead of 4, or wire of 5 ohms per mile instead of 10, either of which would affect the ratio in like manner. But the resistance of the line, referred to in (242), taken in units of the first column of Table X, is now only 1,000 instead of 2,000, and the percentage of received currents is therefore raised from 26.6 to 64.8. On a line of 250 miles, it would be raised from 14.7 to 52.9; that is, more than 3^ times as much current would be received at the end of the line. 255. Best Method of Improving Efficiency.— A line of 400 miles of No. 9 iron wire of 15 ohms conductivity resistance per mile, and carried upon glass insulators giving 4.5 megohms each in very unfavorable weather, with 30 poles per mile, would have an efficiency ratio (242) of i : 10,000, the same as that assumed in Table X. The true conductivity of the line would be 6,000 ohms, and the percentage of the entering current which would reach the distant end would be only 2.15. If a copper wire of 5 ohms per mile were substituted, without changing the insulation, the percentage of current received would at once be increased from 2.15 to 26.6, or more than 10 times as much, the efficiency ratio being now i : 30,000. The cost of the respective wires for 400 miles would be approximately as follows : The same or a better result may be more advantageously reached by improving the insulation. If, for example, instead of the 4.5 megohm glass insulators, the German porcelain insulators of Fig. 92, p. 118, were used, the minimum resistance of which, according to the test, p. 120, is 19 megohms, we may safely assume that the insulation will be three times as high as with the glass. This will give us, with the i5-ohm wire, an efficiency ratio per mile of 15 : 450,000 or i : 30.000, as before. It appears, therefore, that the operative value of a long line in wet weather may be increased as much by expending $2,400 in improving its insulation, as by expending $7,944 in improving its conductivity. On the other hand, it must be taken into consideration that when the line is designed to be employed for multiple transmission, a marked advantage results from high conductivity, altogether irrespective of the question of insulation efficiency. Several different strengths or values of current, in this case, require to be distinguished from each other by the selective action of the receiving instruments, and the certainty with which this can be effected depends largely upon the maximum volume of current which the line is capable of transmitting. The interference arising in fine weather from static induction (314) is also relatively much less marked upon lines of high conductivity. 256. The beneficial effects of improving the insulation on long circuits are forcibly exhibited in the following table, which contains the results of computations made by Moses G. Farmer.6 These results seem scarcely credible to those who have accustomed themselves to the belief that the defects of insulation on our existing lines are unavoidable, and that the only available remedy is the costly one of increased conductivity. Yet the correctness of the theory is abundantly proved by the working of such a line, for example, as the Atlantic Cable of 1866, which was 2,185 miles in length ; had a resistance of about 3.7 ohms per mile, a total of over 8,000 ohms ; and which worked well with an c. m. f. of 10 volts, because of its high insulation. It is also a familiar fact that any good line can be worked at full speed for a distance of more than 1,000 miles in cold dry weather, when the leakage due to imperfect insulation is almost imperceptible even with sensitive measuring instruments. 257. Apparatus Essential in Telegraphy. — It has been stated that the art of electric telegraphy consists in the production, control, and organization of electric signals, which may be either visible or audible (2). The system of telegraphy now generally used in America under the name of the " Morse," produces audible signals at a distance by means of an instrument called a sounder, which comprises an electro-magnet ; a vibrating armature ; and a key consisting essentially of a lever and contact-points, whereby the transmitting operator is enabled to interrupt and restore the circuit with convenience and rapidity, for the purpose of forming the conventional signals. 258. Construction of the Key. — The key is made in many different forms, not essentially differing in principle. Its essential portions consist of the lever, the finger-knob, the spring, the switch or circuit-closer and the base. The lever, which was formerly made of cast brass, is now more usually punched from sheet steel, which renders it not only stronger but of less weight and more easy to be manipulated with rapidity. A pattern of key much used is shown in Fig. 109. The lever A, 4 or 5 inches in length, slightly curved, is provided with trunnions at G, which turn between adjustable set-screws D D. The lever has a small vertical reciprocating movement upon its axis, limited in one direction by the adjustable set-screw F, and in the other by a platinum contact-point c inserted in a brass stud C, insulated from the frame M of the key. The finger-knob or button B, usually of non-conducting material, enables the key to be conveniently depressed at pleasure by the finger of the operator. This action brings a platinum contactpoint d, inserted in the under side of the lever A, into contact with the one above mentioned which forms a part of the anvil.1 One of 1 Platinum is used for these and other contact-points in electrical apparatus, for the reason that the infusible properties of this metal prevent it from being oxidized by the electric spark, which tends to pass between separated conductors whenever the circuit is broken. This spark, in the case of the key, is principally due to the inductive eft's- Modifications of the Key. the circuit-wires P is clamped to the brass rod J by means of a clamp-screw L underneath the table, this rod being in metallic connection with the base. The other circuit-wire is attached by means of another clamp-screw K to a similar brass rod I, connected with the anvil, and insulated from the frame. When the key-lever A is depressed, the circuit between the wires P and N is closed, precisely as if the wires themselves had been brought into contact with each other. position. The upward pressure of this spring is adjusted by means of a set-screw H. When the key is not in use, the main circuit is closed by shoving the pivoted switch-lever S into a recess formed between the lip of anvil C and the frame M, thus establishing an electrical connection between the wires P and N, notwithstanding the separation of the contact-points c and d. 259. Modifications of the Key.— Of late years other forms of keys have been much used, in which trunnions are dispensed with. One of these is shown in Fig. no. The lever is secured to a rear- charge of the electro-magnets in the circuit ; when there are a great number of these, the spark sometimes becomes very troublesome (196). Iridium, another infusible metal, is sometimes used instead of platinum. wardly extending flat steel spring, the opposite end of which is firmly fastened by screws to the base. An adjustable set-screw passes through a hole in the center of the spring and its nut may be set to FIG. no. Western Electric Key. bear upon its upper surface, thus enabling its flexibility to be regulated as desired. A second check-nut is capable of adjustment to regulate the stroke, or extent of vertical vibration of the key-lever. A modification which is applicable to all keys, consists in placing two binding-screws, one of which is insulated, upon the top of the base as in Fig. in, to which the wire connections are made, thus avoiding the necessity of boring holes through the table, which is sometimes objectionable. FIG. in. Victor Key. 260. Adjustment of the Key. — In adjusting a key for work, the best result will usually be attained by giving the lever a small movement with a moderate upward spring-pressure. Trunnion keys should be carefully adjusted, so as to prevent unnecessary lateral movement on the one hand, and unnecessary friction on the other. The Sounder. A trunnionless key, working upon knife-edged bearings, now very extensively used and known as the "Victor," is shown in Fig. nr. By this device, friction and weight are reduced to a minimum, while adjustment is rendered more convenient. In this and in the preceding pattern of keys, the electrical contact being made through continuous metal, is more perfect than is possible when trunnions are used. FIG. 112. Elevation of Sounder. the size and proportion of .that shown in Fig. 69, page 91, and an armature A fixed transversely upon a brass lever B about 3 inches in length, fitted with trunnions at C and mounted between transverse set-screws in the same manner as the key. Two other set-screws D and F form adjustable stops, which limit the vertical motion of the lever in each direction. When the circuit is closed through the electro-magnet, the armature is strongly attracted, and is thereby made to strike forcibly against a sounding-post or bridge G through which the vibration is imparted to the table upon which the instrument is secured. When the magnetism disappears, the lever is thrown against the upper stop F by the recoil of an adjustable spring H. The operator interprets the signals by mentally noting the difference in character between the sounds of the down-stroke and the up-stroke, and by estimating the space of time intervening between them, as will be hereinafter explained (378). Fig. 113 is a common pattern of sounder, about two-thirds the actual size. The helices of the electro-magnet are wound with insulated wire, the thickness and convolutions of which depend upon the strength of current with which the instrument is designed to be used. When intended for direct working, in which case the sounder is actuated by the current received over the line Irom the distant station, the helices are wound with wire which may differ in gauge from number 22 to 32 and even 36 (see table, page 94) according to the length or resistance of the circuit in which they are intended to be used. Ordinarily the sounder is operated by a local battery, consisting of a single gravity cell (Fig. 4, page 5), in which case its electro-magnet is wound with number 24 wire to a resistance of about 4 ohms. 262. Short Line Instrument. — When the length of the line on which the sounder is to be used does not exceed 40 or 50 miles, a convenient and compact form of apparatus, consisting of a sounder and key mounted on one base, with proper electrical connections as shown in Fig. 114, and having its electro-magnet wound to a resistance of 20 or 30 ohms, may be employed with advantage. 263. Adjustment of the Sounder. — The adjustment of the sounder may be best effected as follows: — First, loosen the stop D until the armature A rests directly upon the poles of the electromagnet. Second, set the trunnion-screws upon which the lever B turns, as tightly as possible without in the least binding the axis. This can be determined by lifting and letting fall the lever, having Pocket Apparatus. previously slackened the spring H. It should drop freely when released. Third, lay a piece of paper between the poles of the magnet and the armature, and close the circuit through the magnet, FIG. 114. Combination Sounder and Key. so that the attraction exerted upon the armature will clamp ttv paper. Fourth, adjust the screw-stop D, until the armature i* raised just enough, to permit the paper to be drawn out without friction. Fifth, adjust the stroke by means of the screw F. 264. Pocket Apparatus. — Fig. 115 represents a convenient, compact, and exceedingly portable form of direct-working sounder, having a key attached, so as to form a complete apparatus for sending and receiving communications. The engraving is nearly the actual size of the instrument, which, together with its case, weighs but a few ounces, and can be readily carried in the coat-pocket. 265. Box Sounder. — Fig. 116 shows still another combined key and sounder, in which the electro-magnet is of standard dimensions, and is enclosed within a wooden box, the resonance of which materially increases the volume of sound made by the strokes of armature-lever. This apparatus, being complete in itself, is often found useful in the railway telegraph service, for establishing accident. 266. Working by Relay and Local Circuit. — When the line is of considerable length and corresponding resistance (118), or its insulation is defective, as is usually the case in practice (232), the main line current may be too feeble or too variable to satisfactorily operate the receiving instrument. This inconvenience is avoided by making use of an intermediate receiving instrument called the relay, which is included in the main circuit. Its armature-lever has only to perform the function of opening and closing the circuit of a local battery at the receiving station, by which means the sounder can be made to produce any required volume of sound. 267. Construction of the Relay.— The relay consists of an electro-magnet, having its armature delicately poised, so as to be free and capable of being acted upon by minimum magnetic attraction. Fig. 117 represents a design which is largely used. \\ in. diameter, sc^-wrd into a yoke Y, 2 in. long and } in. in thickness. The standard resistance of the coils is about 150 ohms, and the average number of convolutions of wire in the coils 8,500. The FIG. 117. Western Union Relay. usual magnetizing force is about 200 ampere-turns (176). The front ends of the magnet are supported in a vertical metallic frame F, the foot of which is firmly secured to a hard-wood base, by screws from beneath. Two circular openings are formed in this frame, large enough to permit the helices to pass freely through without being fastened in any way. The yoke end of the magnet is supported at S by a right and left screw, or a straight screw with two check-nuts passing through a brass pillar fixed upon the base. This device is capable of imparting to the electro-magnet M a limited horizontal advance or retrograde movement. The armature A in front of the poles is fixed transversely to the upright lever B, the lower end of which is mounted upon a steel arbor turning between two adjustable set-screws, mounted upon standards H projecting from the lower part of the frame F. The armature-lever and armature are permitted a limited movement to-and-fro upon the axis, responsive in one direction to the attraction of the electro-magnet, and in the other the retractile force of the spiral spring T. This motion is limited in one direction by the adjustable screw-stop C, and in the other by a fixed stop of non-conducting material placed within the slotted projection D, through which the lever B passes freely, not touching anything but the stops. The spring T is attached at one end to the lever B by a hook, and at the other end to a thread which winds upon a spindle V provided with a milled head. (See Fig. 117.) This spindle is supported in a socket upon the end of a horizontal brass rod, which slides through a pillar and may be fastened in any required position by a check-screw. The object of this device is to enable the tension of the spring T to be adjusted through a somewhat wide range, the necessity for which will be hereinafter explained. The electrical connections of the relay are as follows : — Upon the base are four binding-screws for the attachment of wires. Only three of these are visible in Fig. 117, the other being concealed by the electro-magnet M. The insulated copper wires projecting from the helices of the electro-magnet are seen to pass down through the wooden base, underneath which they are connected to the two right-hand binding-posts, so that current entering at one bindingpost, after traversing both helices of the electro-magnet, returns to the other and passes on. It has been explained that the function of the relay is simply to break and close the independent local circuit in which the sounder is included, whenever the main circuit is broken and closed, or in other words, to repeat the signals of the main circuit into the local circuit. To this end the armature-lever A is carefully insulated from the frame F by a non-conducting bushing interposed between the lever and the axis upon which it turns. A wire leads underneath the base from one binding-screw to the support of the armature. Another thin copper wire W, coiled into a spiral, connects the armature-lever with its support, being attached to the former by Adjustments of the Relay. 147 a small screw seen in the figure just above the axis. When the armature is attracted by the electro-magnet, a platinum contactpoint near the top of the lever B (Fig. 118) is brought in contact with a corresponding platinum point which forms the tip of the adjustable screw-stop C. The stop C is in electrical connection with the brass frame F, and this is in turn connected with the extreme left-hand terminal binding-post by a wire under the base. Hence it necessarily follows that whenever the two platinum points are brought in contact by the advance movement of the armaturelever in response to the attraction of the electro-magnet, a connection will be formed between the two terminals completing the local circuit through the sounder. 268. Adjustments of the Relay.— The adjustments of the relay are three in number : first, the stroke, or extent of the to-and-fro movement of the armature ; second, the antagonistic action of the retracting spring; and third, the distance between the armature and the poles of the magnet. The first-mentioned adjustment is effected by the front screw-stop C, which is movable, the rear stop being fixed. The maximum separation between the platinum contacts ought never to exceed ^ of an inch, and in case the actuating current is weak, it should be made as much less than this as possible. Under ordinary conditions this adjustment, once properly made, seldom requires alteration. The second adjustment particularly requires judgment and skill on the part of the operator. When the attraction of the electro-magnet is very strong, as is usually the case in wet weather (242), the armature will not fall off promptly, and hence the tension of the spring must be increased by turning the milled head, thus winding the thread and straining the spring. The spring T must never be wound around the spindle V. When the thread has all been taken up, the spindle must be removed to a greater distance from the armature, by loosening the check-screw and sliding the rod upon which it is mounted through the post to a sufficient distance and then clamping it again. In extreme cases the tension cannot be sufficiently increased by this means, and it then becomes necessary to resort to the third adjustment, which consists in withdrawing the magnet by the screws, so as to increase the distance between the poles of the electro-magnet and the armature. 269. The Register. — This apparatus for recording the signals, was originally regarded as an essential part of the Morse system. It is now but little used except at small stations and on railway lines. It consists essentially of a pair of grooved rollers moved at a uniform rate by a system of controlled clock-work driven by a weight or spring. A long narrow strip or ribbon of paper, taken from a roll, passes between adjustable guides, and thence between the grooved rollers, the motion of which draws it along from right to left at a uniform rate. An electro-magnet is provided with a lever similar to that of the sounder (261), and armed at the extremity with a style or point of hard steel, which works in a groove rn the upper roller. As the strip of paper passes between the rollers, a raised line is embossed upon the upper surface of the paper whenever the marking point is forced into the groove by the attraction of electro-magnet exerted upon the armature at its opposite end of the lever. A retracting spring is provided with adjustments similar to those described in connection with the sounder. The paper-guide is capable of lateral adjustment, so that the same strip of paper may, if desired, be used several times, each successive line of characters lying parallel to, and in front of the preceding one. FIG. 119. European Pattern Register. 270. Fig. 119 shows one of the most modern forms of the register, in which the clock-work is propelled by a coiled spring, instead of by a weight, as in the instruments formerly made. The ma- chinery is entirely enclosed in a brass case with plate-glass panels, so as to exclude dust. The end of the strip of paper is inserted through the guide and between the rollers while the clock-work of the register is in motion. The rate of speed at which the paper moves may be varied, within certain limits, by means of a governor acting FIG. 120. Combination Victor Key, Relay, and European Register. upon the retarding or controllling device of the clock-work. The register, relay, and key, are sometimes combined upon a single base with their necessary connections, as in Fig. 120. 271. Adjustments of the Register. — The armature must be so adjusted as not to come quite in contact with the poles of the electro-magnet (262). After the set-screw which limits the movements of the armature toward the electro-magnet has been properly adjusted, the armature should be held down, either by closing the local circuit through the electro-magnet or by the finger ; the register is then started, allowing the paper to run, and the marking-point adjusted, by turning its milled head until a continuous uniform line is produced upon the upper surface of the paper, by the action of the style between the groove and the roller. The embossed line should not be made any deeper than to enable it to be distinctly seen when placed in a transverse light in front of a window. The final adjustment is that of the set-screw which limits the movement of the armature away from the electro-magnet, which should be so fixed that the marking-point will just clear the paper when released by the breaking of the circuit. 272. Causes of Defective Marking. — Imperfect marks will result if the style does not work accurately in the groove of the upper roller. This defect is usually due to the working loose of the screws which form the transverse bearings of the axis of the marking lever, so as to permit too much lateral play, and may obviously be remedied by proper adjustment (260). When such adjustment has been effected it should be let alone. The unnecessary alteration of the adjustment of the pen-lever is frequently the cause of much trouble to inexperienced operators. 273. Ink- Writing Register. — A form of register now much used is shown in Fig. 121, in which the characters are marked upon the upper surface of a narrow strip of paper by means of a small sharp - edged jockey - wheel, driven by the clock-work and supplied with ink by means of a felt roller saturated with thick, oily ink, which revolves in contact with it, being held thereto by a spring. A knife-edge on the end of the armaturelever, lifts the slack of the paper into forcible contact with the tinder edge of the revolving inked jockey-wheel, whenever the arma- black ink. 274. Circuits of the American System.— Telegraphic circuits in the United States and Canada are almost universally arranged upon the modification of the closed-circuit system, shown in Fig. 83, page 1 08. If an operator at any station desires to transmit a communication, he first opens the switch of his key and interrupts the flow of current throughout the line. This causes the armatures of all the relays in the circuit to fall off. He then proceeds to manipulate his key, by closing and breaking the circuit at accurately timed intervals, so as to form the conventional characters of the telegraphic code in the order required to spell out his communication. During this operation, the armatures both of his own and of all the other relays in the circuit, as well as those of the registers or sounders connected therewith, will respond instantaneously to every movement of the key, and consequently the communication may be copied from the sounder or register by an operator either at any one station, or if required, at all the stations simultaneously. As the receiving instrument of the sending operator normally responds to every movement of his key, it is evident that the receiving operator at any station may interrupt him at any time, by opening his own key, and thus breaking the circuit in another place. The sending operator instantly perceives such an interruption, by reason of the failure of his relay and sounder to respond to the movements of his own key. 275. Arrangement of Apparatus at a Way-Station.— The simplest complete combination of apparatus is that found at an intermediate or way-station having but a single main wire. It comprises one set of instruments, viz : a key, sounder or register, relay, local battery, switch, lightning arrester, and the wires connecting the different parts of the apparatus. The manner in which these are usually arranged and connected with each other, and with the line, will be understood by reference to Fig. 122, which represents a complete way-station. The sounder, relay and key may be conveniently placed upon a table about two feet by three in size. The sounder, or its equivalent the register, is best placed in the middle of the length of the table, having the key on the right and the relay on the left. The knob of the key should be about 12 in. from the front edge of the table. The switchboard is most usually placed in an upright position upon the wall above the table, or in any convenient position. The switchboard is not absolutely necessary, but it is a very convenient device for making the necessary changes in the connections of the wires. In the form most commonly employed (see Fig. 131) a device is used similar to that described in connection with the rheostat (Fig. 43, p. GROUND 51), a number of metallic pegs with insulating handles adapted to beinserted between the edges of thick plates of brass, between which they form an electrical connection. 276. Connections of Apparatus of Way-Station. — The way-station in the diagram Fig. 122, may represent for instance, Trenton, N. J.; L being the line-wire from New York to Trenton, and L1, the line-wire from Trenton to Philadelphia. The line-wires are extended into the station building by leading-in wires properly insulated, which are connected with the binding screws i and 2 of" Manipulation of tkc Switchboard. the switch. These binding screws aie mounted upon vertical metallic bars secured to the wooden back-board vsee Fig. 131). Of the instrument wires il leads from the binding screw 4 of the switch to one of the terminal screws of the key. From the other terminal screw of the key, the wire i extends to the first right-hand main terminal of the relay; the other instrument wire /a unites the binding screw 5 of the switch to the second right-hand terminal of the relay; a wire g leads from the binding screw 3 of the switch to the ground (210). The wires of the local or office circuit are run as follows : — From the local battery, the wire e runs to the first left-hand (local) terminal of the relay; the wire/runs from the second lefthand (local) terminal of the relay to one terminal of the sounder or register ; and finally the wire h runs from the remaining terminal of the sounder or register to the other pole of the local battery. It is quite immaterial which pole of the battery is connected to the relay and which to the sounder. purposes are as follows : (i.) To cut out the Apparatus. — Insert pegs connecting i and 2 with 6, as in Fig. 123. The main-line current now passes from the 4- pole of the main battery at New York through the instrument at that station, and thence over the line L to i, and through 6 to 2, thence over the line L1, and through the apparatus at Philadelphia to the — pole of the main battery at that place, and thence to the ground. The - - pole of the New York battery is also connected with the ground, and therefore the circuit is complete. When thus and the others left open (Fig. 124). The key (Fig. 122) should also be opened, which serves to disconnect the wire i1 ; i* being open at the switch. This prevents lightning from injuring the instruments. In thus cutting-out by means of one of the instrument wires, the one which runs to the key should always be made use of, not the one going to the relay. (2.) To cut in the Apparatus. — Insert pegs in 1-5 'and 2-4 (Fig. 125) or else in 1-4 and 2-5 (it is immaterial which, though the former is most usual), and remove the pegs from 1-6 and 2-6, taking care that the remainder of the holes are also open. It is better to peg holes 1-5 and 2-4 before taking out 1-6 and 2-6, which can readily be done if four pegs are provided, as then the circuit of the main line need not be interrupted even for an instant. Care should always be taken before "cutting in " the instruments to see that the key-switch is closed. 278. Testing for Disconnection.— In case the line is broken, or the circuit is open, as it is termed, it becomes necessary for the way-station to test the circuit. This is done by grounding the line. Suppose the line disconnected at some unknown point. Trenton already has pegs in the holes 1-5, and 2-4 (Fig. 125), as in the ordinary manner of working, but of course perceives no current. A spare peg is placed in 1-6 (Fig. 126), the effect of which is to connect the end of the New York line L with the earth wire g. This completes the circuit of the New York battery, but produces no effect on the Trenton instrument, as the current does not pass through it. The peg is then transferred from 1-6 to 2-6 (Fig. 127). The circuit of the New York battery is again completed as before, except that it now includes the Trenton instrument, its course being from the line wire L through the instruments as usual, and through the peg 2-6 to the wire g, and finally to the ground. Trenton now becomes a terminal station, working with New York by means of the battery at the latter place. This result demonstrates to the operator at Trenton that the disconnection is between that place and Philadelphia. If, on the contrary, the circuit had been completed through the relay when the peg was inserted in 6, it would have shown the break to have been in the opposite direction. It sometimes occurs that the circuit cannot be completed on either side, and the line appears therefore to be interrupted in both directions. In that case the trouble is in all probability within the limits station finds by the above test that the line is interrupted in a particular direction, it is his duty to report the fact at once to the terminal station in the opposite direction, from which he should receive instructions in regard to his proper method of procedure, so that the uninjured portion of the line may be operated until the difficulty is removed. 280. The Wedge Cut-Out.— This device is often used at way-stations instead of the switch last described. It is termed a nected to the opposite sides of a wedge, as it is technically termed, which is shown, full size, in Fig. 128. It consist's of two* brass plates insulated from each other by a thin plate of hard rubber, and provided with a handle of the same material. The ends of the line-wire are connected with the two binding screws at the top of the baseboard (Fig. 129). The right-hand binding screw is connected, by a wire under the baseboard, with an elastic brass strip. The upper end of this strip is rigidly attached to the board, while the lower end is armed with a brass pin, which, by the elasticity of the strip, is pressed firmly against a second pin, also screwed to the board. The stationary pin is attached by means of a wire to the other binding screw, and is thus placed in connection with the line-wire. This device is termed the spring-jack. When the wedge, carrying the flexible instrument wires, is inserted between the two pins, it separates them, thereby breaking the circuit of the main line, but simultaneously opening a new path for the current through the two parts of the wedge and the instruments. Thus the latter may be inserted into or withdrawn without interrupting the main circuit, by a single instantaneous movement. For many places this is an exceedingly simple and effective arrangement. It is sometimes used for large stations, in combination with the peg-switch, as will be hereafter shown (286). The wedge cut-out is usually provided with a lightning arrester and ground-wire connection, arranged with pegs, as in Fip". ^29, in much the same manner as the switch in Fig. 122. 281. Multiple-Wire Switchboards. — It very often happens that different lines traversing the country in the same or in different directions pass through the same way-station. The necessities of the service sometimes require that there should be apparatus provided for each line, but more frequently a smaller number of instruments is sufficient, provided means are furnished by which any one of them can be inserted into the circuit of any line at pleasure. 282. Multiple Spring- Jack.— The simplest way of providing for this is to make use of a number of spring-jacks (Fig. 130) corresponding to the number of line wires, and placed side by side upon the same baseboard. The wires for each separate set of instruments terminate in a wedge, and by this means any instrument may be placed in connection with any required line-wire at a moment's notice, simply by inserting its wedge into the corresponding spring, jack. 283. Universal Switchboard. —The arrangement last described makes no provision for interchanging the line-wires among themselves — a proceeding which is necessary, for instance, when two or more lines running in the same general direction are each interrupted, but at different points. By connecting the uninjured portions of different lines with each other, it is often possible to "patch up" one or more complete circuits for the transaction of business. The wirt-s are interchanged or cross-connected, as it is termed, at the different way-stations, in accordance with instructions given by the official in charge of the circuits at the terminal station. In order to conveniently ac- 284. Manipulation of the Universal Switchboard. — The various changes, other than those which have been explained in connection with the single-wire switch (277), are made as follows: pegs as in Fig. 132, leaving the remaining holes open. (2.) Lines cross-connected or interchanged. — In this case, it is required to connect No. i wire west with No. 2 wire east, and No. i east with No. 2 west. Insert pegs as in Fig. 133, leaving the other holes open. Both instruments A and B are now included in the circuit. To leave instrument A out of the circuit, change the pegs to the position shown in Fig. 134. Instrument B is cut out by placing the pegs as shown in Fig. 135. In Fig. 136, the wires are FIG. 135. (3.) Lines grounded or put to earth. — This may be done on either No. i or No. 2 wire, east or west, by inserting pegs along the ground wire bar G, as required, as in the single-wire switch (277). (4.) Lines looped. — It is sometimes required to loop two wires, as it is termed, for making tests or other purposes. To loop i and 2 east, with instrument A in circuit, insert pegs as in Fig. 137 ; without instrument A, insert pegs as in Fig. 138. Numbers i and 2 east may be looped in a corresponding manner. The foregoing explanation will sufficiently illustrate the principle upon which the switch is manipulated. Switches are made to accommodate any number of wires, from i to 50 or more. 285. Arrangement of the Apparatus at the Terminal Station. — The simplest possible arrangement at a terminal station is similar to that shown in Fig. 122, but it is rare that such a station does not contain more than one line-wire. More than one line entering a terminal station renders it desirable to employ a switch similar in construction to Fig. 131, but with its connections differently arranged, for at a terminal station, provision must be made for connecting and disconnecting the main batteries as well as the instruments. Terminal Switchboards. both the peg-switch and the wedge cut-out are employed. In the largest class of terminal stations the switchboard is divided into a number of sections, each section accommodating a certain portion of the lines entering the office. The wires are usually distributed ac- cording to the geographical location of the region with which they connect. The lines running eastward, for example, are placed in one section of the switch, and those running northward in another, while still another section accommodates the local lines, etc., etc. The switchboard represented in the figure is provided with 50 vertical bars, to the lower ends of which the line-wires are connected. Between each pair of upright bars is placed a row of metallic disks, to which the battery terminals are connected. All the disks in each separate horizontal row are electrically united at the back by horizontal copper wires, the extreme left-hand disk having a distinguishing number opposite it. The vertical bars are connected at pleasure with the horizontal disks at any required point by the insertion of a peg at the point of intersection. Immediately underneath the lower end of the vertical bars are placed a corresponding number of springjacks. Each main wire entering the switch passes first through one of the spring-jacks, and thence to the corresponding bar. Each spring-jack bears an ivory plate, upon which may be engraved the designating number of the circuit to which it is attached. The baseboard of the switch is of mahogany, cut in strips ,2 in. wide by i in. thick, separated by a space of -J in., to prevent injury to the brass-work by shrinkage. Each strip of mahogany supports two vertical bars and one row of disks. The spring-jacks are held in position by stout spiral wire springs attached to the back of the switch. One row of horizontal disks is connected directly with the earth. The lightning arresters are not combined with the switch, as in the smaller stations, but are placed at the point where the wires first enter the building. The instruments seen upon the shelf or counter in front of the switch are used for testing. They are provided with flexible connections and wedges (280), so that they can be thrown into the circuit of any desired line at a moment's notice. 287. Instrument Tables. — In most large stations, the different sets of apparatus are arranged in groups of four, upon tables about 4 by 6 feet, divided by two vertical intersecting screens into four sections, each accommodating a complete set of instruments, sounder, relay, and key. A group of 4 pairs of instrument wires extends from the switchboard to each table, and a second group of 4 pairs of local wires extends from each table to the local batteries. The wires are usually insulated with a double coating of gutta-percha, and are then laid up in cables and bound with tarred tape. It was formerly the practice to group a number of local circuits together, using a common return-wire for the group. Experience has shown that this arrangement is objectionable, and that it is better to keep all the circuits, main and local, of each line, distinct from those other lines in the same station. venting danger of injury to the instruments and operators by atmospheric electricity, and from the powerful currents employed in electric lighting, which sometimes find their way into telegraphic conductors. Atmospheric electricity, being of enormous potential, will take a short route through a poor conductor, or even through a non-conductor, in preference to a longer one through a better conductor, while the reverse is true in respect to the currents of comparatively great volume and low potential employed in telegraphy. 289. The Plate Lightning Arrester. — A common form has a flat brass plate connected with the ground wire. Other plates of brass which rest upon this are electrically separated therefrom by thin sheets of non-conducting ma- thus discharged into the ground without injuring the apparatus. Fig. 140 shows one of the most common forms. The ground wire is connected to the upper plate by the binding screw shown at the left, and the line-wires through the smaller transverse plates beneath. The confronting faces of the plates are surfaced with V-shaped grooves, which have been found by experience to facilitate the discharge of lightning. The lightning arrester is often combined with the switchboard, examples of which construction may be seen in Figs. 127 and 290. The Safety Fuse. — Another very effectual means of protection consists in interposing 3 or 4 inches of the thinnest copper wire which can be procured (say No. 36) in each circuit between the line and the instrument. An abnormal current, whether arising from atmospheric disturbances or from contact with electric lighting or power circuits, instantly fuses the thin wire, interrupting the circuit, and thus effectually protecting both the operators and the apparatus This device, of course, requires careful attention, inasmuch as it is necessary to replace the fuse-wire after the disturbance has ceased. tern, free from dirt and moisture. Neglect of this precaution is liable to cause serious interruption of communication. A discharge of atmospheric electricity often forms a permanent connection between the line and ground plates. Hence, arresters should be frequently taken apart and examined, and this should especially be attended to immediately after a thunder-storm. 292. The Repeater. — When the length of a telegraphic circuit exceeds a certain limit, dependent upon the ratio of its insulation to its conductivity resistance, the working margin (220) becomes so small that satisfactory signals cannot be transmitted, even by the aid of increased battery-power. This limit, under the existing conditions of insulation, is much less in wet weather than in fine. Under such conditions, it was formerly necessary to retransmit all communications at some intermediate station, but this duty is now usually performed by the repeater. This is simply an organized apparatus, in which the sounder (or in some cases the relay), receiving the signals through one circuit, opens and closes the circuit of another line, in the manner that a relay opens and closes the local circuit of a sounder (261). The repeater is also used to connect one or more branches with the main line, for the purpose of receiving press-news, etc., simultaneously at widely separated points. Under these conditions the stations in connection may correspond with each other as readily as if all were upon the same circuit. By making use of repeaters it is quite practicable to telegraph direct, when required, between places situated at distance of several thousands of miles apart. 293. Manual and Automatic Repeaters. — The different repeaters which have been devised are almost innumerable. They may, however, be classified as manual and automatic. The manual repeater is usually employed for temporary purposes, as it requires the constant attendance of an operator to maintain the connections of a switch, in accordance with the direction in which the communication is passing. At repeating stations where a permanent service is maintained, the automatic repeater is employed, which requires no supervision, other than that necessary to insure the apparatus being kept in proper adjustment. 294. The Button Repeater. — A form of manual repeater much used is shown in diagram in Fig. 141. It is known as the button repeater. The western main line, after traversing the coil of the relay M1, passes through the contact-points of armature of sounder S2 (the movements of which are controlled by relay M2) and thence to main battery B1, the opposite pole of which is connected The Button Repeater. to ground. In like manner the eastern line traverses the coil of relay M2 and the contact-points of sounder S1 and to battery B2 and ground. It is necessary to provide, in addition, means for u cutting out," or closing the circuit around the breaking-points of each sounder, otherwise the apparatus will be inoperative. For example, suppose the eastern line to be opened by the key of the operator. This allows the armature of relay M2 to fall off, opening sounder S2, breaking the circuit of the western main wire at its contact-points. This causes the armature of relay M2 to fall off, followed by that of sounder S1, and breaking the circuit of the western line also. The operator of the eastern line cannot now close the circuit, because it is still open in another place, viz., at the contact-points of sounder S1. The switch shown at L, technically termed the button, removes this difficulty, for when it is swung to the right it closes a springcontact C1, forming a connection between the contact-points of sounder S1, enabling the operator of the eastern line to open and close its circuit at pleasure, while his signals are repeated into the western line by the action of the contact-points of sounder S2. The switch or button shown at L in the diagram, consists of two pairs of contacts C1 and C2, normally closed by a spring action, one pair or the other being separated as the handle L is moved to the right or left. If the handle remains in the center, both sets of contacts are of each other. 295. Wood's Repeater. — Another form of button repeater, known as Wood's, is illustrated in Fig. 142. In addition to the functions performed by the apparatus last described, means are here provided for joining the two lines through in one circuit without repeating. The apparatus of the button is shown in full, with the instruments and batteries, etc., in outline for convenience of explanation. M1 and M^ are the eastern and western relays, S1 and S2 the eastern and western sounders. The local connections are omitted o avoid multiplicity of lines, but are run as usual. The eastern and western main batteries at E2 and E1 have opposite poles to ground at the repeating station, so that when the lines are connected through, the two batteries will coincide. The following results may be obtained with this apparatus : and B1. (3.) Two independent circuits arranged for repeating. — The peg at 4 is inserted. If lever L be placed in the position indicated by the reference figures 2, 2, the eastern sounder repeats into the western into the eastern circuit. 296. Management of Button Repeater. — The duty of an operator in charge of the button repeater is very simple. He has only to keep the relays properly adjusted, and when he hears either sounder fail to work in unison with the other, to instantly reverse the position of the lever L. 297. The Milliken Automatic Repeater. — This may be considered the standard repeater of the United States, although many others have obtained more or less acceptance. All automatic repeaters embody one essential principle, which is this : The movement of the lever of the relay or sounder on the receiving side of the apparatus brings into action some device for bridging the contact-points of the opposite sounder, before breaking the main circuit on the second line. This is usually effected by some form of springcontact, although there are different ways in which s-uch a device can be applied to produce the result sought for. The principle of the Milliken repeater is shown in Fig. 143. The main and local circuits are run precisely as in the button repeater (141). The automatic device for closing the opposite circuit is applied to the contactlever of each of the relays ; for example, the relay M1 has a supplementary local magnet L1, the armature of which, falling off under the action of its retracting spring, prevents the armature of relay M1 from likewise falling off, because its spring is adjusted to a stronger tension than the relay-spring. The local magnet L1 is actuated by a local circuit which is controlled by a contact-point on the lever of the opposite sounder S2. When the sounder lever falls off, it first breaks the supplementary local circuit, and holds down the armature of the opposite relay, just before the main circuit through that relay is broken. This postponement of the breaking of the main circuit is effected by the spring-contact on the sounder lever. Hence in this repeater, the apparatus on the east side remains quiet while the western line is working and vice versa. The Milliken repeater is provided with buttons, not shown in the figure, for cutting out the contact-points, so that the two lines can be worked separately, as in the case of the manual repeaters. 298. Management of Automatic Repeaters. — In repeating signals from one circuit to another, the sounder-lever which carries the contact-points has to move a certain distance, after the circuit of the first line is closed, before it can close the circuit of the second line. This occupies a definite time, so that the duration of the current or length of each signal sent forward, is shorter than that received from the transmitting station. A second repeater shortens the signals still more, so that ultimately the signals may fail altogether. This may be partially remedied in practice by the skill of the sending operator, who, in working through a repeater, should transmit his signals moreyfrw/y, as it is termed, that is, increase the duration of the key contact (374). It is also important that the sounder levers should be permitted the least possible movement compatible with the proper operation of the spring contact-points and with convenience in reading. The armatures of the supplementary local magnets seldom need adjustment if the batteries are kept in good condition. The adjustment of the relays is precisely the same as in ordinary apparatus. The tension of the retracting springs of the sounders, on the other hand, should be very moderate, just enough to raise the armature when released. A repeater works most efficiently when the signals have what is termed a " dragging " sound. When interrupting the sender through a repeater, the receiving operator should first hold his key open for two or three seconds. 299. The Dynamo-Electric Generator.— In some large telegraphic stations, where the number of lines to be supplied is very great, dynamo-electric machines have been substituted for batteries with highly satisfactory results. A minute description of the different organizations of apparatus or plants which have been employed does not properly fall within the scope of the present treatise, but the following explanation may suffice to render the principles of operation comprehensible. 300. Characteristics of the Dynamo-Current. — The theoretical principle of the dynamo has been briefly set forth in a foregoing chapter (80). From the explanation there given, it will be understood that this machine, in its elementary form, produces a series of waves or undulations of electromotive force of alternating polarity. Beginning at zero, for example, the e. m. f. gradually increases to a positive maximum ; then gradually falls to zero, then rises again to maximum negative, then falls again to zero, and so on indefinitely in the manner graphic service, which requires a normally continuous current, of determinate polarity and of approximate uniform strength. The alternate pulsations produced by the revolutions of the armature are therefore rectified by means of a device called a commutator, the effect of which is to reverse every alternate wave, so as to transform the alternating waves into a series of waves all positive or all negative, as the case may be. If the armature be provided with two coils, placed at right-angles with each other, so that one is in a position of maximum at the same instant the other is in the position of minimum action, and the two effects be combined, the result will be a distant coils upon the armature, and superposing their effects, in the manner indicated by the dotted outline at the left, it is practicable to obtain a current which is practically constant, and is found to be perfectly well adapted for telegraphic purposes. For this reason the rotating armature coils of the dynamos employed in telegraphy are divided into a large number of sections, each coming tice, the far more powerful field produced by electro-magnetism is for many reasons preferable. The electro-magnet which maintains the field may be excited by a current traversing a shunt or branch of the armature circuit (140), in which its helix is included, from which circumstance such a machine is termed a self-exciting dynamo, and specifically a shunt-wound dynamo. Fig. 146 is a theoretical diagram, and Fig. 147 a perspective view of a shunt-wound dynamo such as is used in telegraphy.2 the theoretical dynamo (Fig. 26, p. 33), it will be observed that the armature coils terminate in two semi-cylindrical metallic segments carried upon the shaft. Two stationary metallic collectors, termed brushes, are made to rub upon the segments at opposite points of the circle as they revolve, the whole apparatus being termed the commutator. In Fig. 146 there are a considerable number of segments corresponding to an equal number of armature sections, and two brushes, which form respectively the positive and negative poles of the dynamo-electric generator. The thick black line in Fig. 146 represents the exterior or work circuit. The shunt circuit for exciting the field-magnet is shown by a thin line, the extremities of which are likewise united to the respective terminals or brushes. The direction in which the currents flow in both the main and shunt circuits is denoted by arrows. a This particular machine is known as the " Edison No. 2." It is run at a speed of 1200 revolutions per minute, and has a capacity of about 40 amperes. The resistance of the armature is about 0.1 ohm and of the field-magnet coil about 30 ohms. Characteristics of the Dynamo. 169 303. Characteristics of the Dynamo. — Each dynamo, when driven at a definite and uniform speed, maintains a practically uniform difference of potential (143) between its terminals or brushes, which is dependent upon the original construction of the machine. This corresponds to the difference which is maintained between the poles of a voltaic element, and is due to the e. m.f. of the machine, or of the cell, as the case may be. The especial advantages of the dynamo over the voltaic battery are: (i) its small internal resist ance (131) and consequent capacity to feed a very large number of separate lines without interference, and (2) its economy, both in space occupied and in cost of maintenance, in case the number of wires to be supplied is large. 304. Dynamos in Potential Series. — In a large telegraph station the different lines necessarily vary greatly in their length and resistance, but it is nevertheless requisite that the same quantity of current should be as nearly as possible supplied to each. This renders it necessary that the electromotive forces applied to the respective circuits should differ accordingly. This is effected through the agency of a series of separate dynamos connected together upon the same principle as a series of cells in a battery (132). In the Western Union telegraph station in New York, for example, there are 5 independent dynamos connected in a series, as indicated in the diagram, Fig. 148. These have potentials as follows : A", 70 volts ; B, 70 volts ; C, 60 volts ; D, 60 volts ; E, 65 volts. One terminal of dynamo A is connected to the ground, the wires i, 2, 3, 4, and 5 are FIG. 148. Dynamos in Potential Series. led to corresponding horizontal bars on the station switchboard, from the point of connection between each two adjacent dynamos of the series. These bars are respectively termed the first, second, third, fourth, and fifth potentials. The voltage of each potential, and the average resistance of the individual circuits fed therefrom, are as follows : As the different lines are each connected to one of the vertical bars on the switch (Fig. 139), of which there may be any number, it will be easily understood how any line may be supplied with the particular potential which it requires, simply by pegging it to the appropriate horizontal bar upon the switchboard. 305. Positive and Negative Dynamo Series.— As both positive and negative potentials of the various voltages are required in a large station, two separate series of dynamos are employed, similar to that shown in Fig. 148, one having its positive and the other its negative terminal to the switchboard and line. A third series, Multiple Telegraphy. 1 7 1 of similar arrangement and capacity, is also provided, which has reversing switches, so that it may be made to send either a positive or negative current to line. This may be used at will as a substitute for either of the two regular series in case of accident. Each series of five machines is driven by a 15 horse-power steam-engine. 306. Arrangement of the Shunt Coils.— It will be observed that the last dynamo E in the series (Fig. 148) is necessarily called upon to furnish less current to the lines than the others. The surplus power of this machine is therefore utilized with advantage to furnish current through a shunt or derived circuit, not only for exciting its own field, but the fields of all the other machines in the series. A branch or derived circuit is taken from each terminal of this machine, and the field coils of each of the five machines of the series are connected across from one branch to the other in parallel, as shown by the thin lines in Fig. 148, so that each receives an equal portion of the branch current. 306 a. Capacity of the Dynamo Generator. — A plant of the capacity of that which has been described can be made to furnish for supplying 1000 lines, and yet is so compact that it may be installed in a small room. 307. Multiple Telegraphy. — Within thirty years from the first establishment of the telegraph, the inconveniences arising from the multiplication of wires on the principal commercial routes of the United States proved so serious that it became urgently necessary to adopt measures of relief. The effort to devise an effectual remedy led to the invention of systems of multiple telegraphy, in which the same conductor might be used for the transmission and reception of more than one communication at the same time, either in the same or in opposite directions. The most generally useful of these have proved to be those which have been termed the diptex, which transmits two messages in the same direction at the same time ; the contraplex, which transmits two messages in opposite directions at the same time ; and the quadruple, which is capable of transmitting two messages in each direction at the same time. . The contraplex is more generally known as the duplex. The principle which is common to all these systems is a provision whereby the receiving instrument at the home station, while free to respond to the signals of the key at the distant station, shall not respond to the signals of its associate key. 308. The Differential Electro-Magnet. — It has been heretofore explained that the attractive force of the cores of an electromagnet depends upon the ampere-turns in its coil (176), that is to say, first, upon the number of turns in the magnetizing helix, and second, upon the strength of current in amperes traversing the wire. It has also been explained that the polarity of the core is determined by the direction of the circulating current (168). It follows from these two considerations, that if two currents of equal quantity are simultaneously made to pass in opposite directions an equal number of times around a magnet core, they will neutralize each other's effect, and no magnetism can be developed in the core. An electromagnet of this kind is termed a differential magnet. 309. Construction of Differential Magnet. — There are several ways in which a differential magnet may be constructed, all involving essentially the same principle. Two independent wires must be provided for the two opposing currents. These may be wound side by side throughout the whole length of the helix ; they may be disposed in concentric independent helices ; one helix may be wound on each of the legs of a U magnet, or, what is perhaps most commonly done, the helices may be divided into sections by equidistant non-conducting planes at right-angles to their axes, and the alternate sections connected with the respective circuits. differential relay, the rheostat, and the condenser. Fig. 149 is a diagram of the apparatus at one of the 'two terminal stations. The transmitter D is virtually a key, which instead of being actuated directly by the ringer of the operator, receives its motion from the armature of an electro-magnet S in the circuit of local battery L1, which is closed and broken by an ordinary key K. The key-lever D of the transmitter has a spring contact-lever N pivoted at n and having a contact 9 which normally rests upon a fixed stop ft, from which it is lifted by the contact 0 each time the key K is depressed. The differential magnet is shown at M, and is wound in either of the ways heretofore referred to (309) with two wires, but otherwise does not differ from the ordinary single-wire relay (267). The actual construction of the transmitter is best seen in Fig. 150. The springcontact here shown differs in form, but not in principle, from that outlined in Fig. 149. The spring in this instrument is carried upon the lever, upon a little insulating pedestal, and normally presses upward against a stop affixed to the free end of the lever. When the armature is attracted, the opposite end of the lever is raised, and the free end of the spring touches the adjustable contactstop fixed above it in a standard. The object of this device, as will be hereinafter seen, is to close one contact before breaking the other, or in other words, to transfer a current from one branch of the circuit to another without interrupting it. 311. Circuits of the Single-Current Duplex. — Tracing the circuit of the line entering the station in Fig. 149, it will be seen to first pass through one wire of the differential relay M, entering by wire 3 and thence going by wire 2 to contact-lever n, and thence through stop 9 and wire 6 to the earth. Hence currents entering from the distant station will actuate relay M and sounder R, pre- cisely as in the open-circuit system ^212). If now, at a time when no current is coming from the distant station, transmitter-lever D be depressed by the closing of key K, the terminal of main battery B will be brought, at the point o, into contact with spring-lever N, and will almost simultaneously lift it from point h. This in effect transfers the in-coming line from the ground-wire 6 to the batterywire i, and hence a current will rlow through wires 2 and 3 and one coil of the differential magnet m to the line, finding its way to the ground at the distant station. But it will furthermore be observed that a branch leaves the line at the point #, and leads by way of wire 4 through the opposing wire of the differential magnet M, and thence by way of 5 directly to the earth at the home station. Now it is evident that the outgoing current from battery B must divide between the two branches at the point a in the ratio of their respective resistances (134), and if these be equal, the currents must necessarily be equal (140). This equality of resistance is effected by inserting a rheostat X1 (106) of german-silver wire into the branch, so as to make its resistance equal to that of the line. When this has been done, it is evident that the outgoing currents, being equal and opposite in their effects, can produce no magnetism in the relay M, and hence the latter cannot respond in any way to the signals of its associated key K. But this will not in the least interfere with its capacity to respond to the action of currents transmitted by the distant key. In such case one wire of the relay will be traversed by the current due to the conjoint or superposed action of both terminal batteries, while its action is opposed in the other wire of the relay only by the current of the home battery. The incoming current, therefore, produces upon it precisely the same effect as if the current of the home battery were not present. 312. The Artificial Line. — The branch from the point a through 4 and 5 to the earth at the home station, is termed the artificial line, and the whole problem of contraplex, generally termed duplex telegraphy, consists in simultaneously reproducing in the artificial line, as nearly as may be, all the electrical conditions of the external or working line, and in causing them to act in an opposite sense upon the home relay. There are two conditions in respect to which the actual line is subject to continual variation, viz., as to its resistance (115) and its electrostatic capacity (147). 313. Balancing the Resistance. — The effect of imperfect insulation upon the resistance of the line has already been referred to (242). It is greatest in fine weather and least in wet and foggy weather. The resistance of the artificial line is, however, very easily 314. Electrostatic Capacity of the Line.— In order that the process of adjusting the electrostatic balance of the artificial line may be understood, it is necessary first to explain the nature l l and origin of the corresponding phenomenon as exhibited upon the main line. Whenever electrical generation occurs, there always exists, besides a EARTH EARTH source of generation at which the FlG. I52. Recombination of Positive and normal equilibrium is first disturbed, Negative Electricity, (i) certain conditions which allow the positive and negative electricity thus separated to recombine, or else (2) certain other conditions by which the electricity generated is accumulated on two surfaces separated by a medium through which it either cannot recombine, or (3) can only recombine less rapidly than the source can generate.8 The first condition referred to exists in the case of a cell, or series of cells, having the poles joined by a conductor of inappreciable resistance (Fig. 152). The second condition exists in the case of an insulated telegraph line of considerable length, connected to one pole of a grounded battery and open at its distant end (Fig. 153). The third condition exists when the line assumed in the last case, instead of being open at the distant end, is there connected to the earth, either directly or through an instrument or other appreciable Effect of Currents of Charge and Discharge. 1 77 315. Electrostatic Accumulation upon Insulated Conductor.— When, therefore, a quantity of electricity flows through a long insulated line, the electricity which constitutes the initial portion of the current, being prevented by the resistance of the circuit from recombining instantaneously, is stored up or accumulated upon the surface of the conductor. The quantity thus accumulated depends upon the diameter and length, or, in other words, upon (i) the superficial area of the conductor,, (2) its distance from the earth, or other conductors in electrical connection with the earth, and (3) . upon the character of the insulating medium which intervenes between it and the earth. Thus, in any long insulated circuit, a certain portion of the current which would otherwise reach the distant station and be available for producing signals, is abstracted and tied up in the form of a static charge. If the line be very long and the duration of the current be very short, the static charge may absorb the whole of it, so that no effect will be appreciable at the distant station. As the static charge takes up the initial portion of every current sent, the effect is the same as if its appearance at the distant station were retarded or delayed, and hence the apparent velocity of the current is lessened. The initial rush of current into the line, sometimes called the current of charge, produces for an instant a much more powerful magnetic effect upon the armature of the relay than does the permanent current which continues to flow after the conductor has been fully charged. The momentary effect thus produced upon the relay is termed by the operators the kick. It varies in amount with the electrostatic capacity of the line ; the longer the line and the more perfect its insulation, the higher its capacity to receive charge and the more the force manifested by the charging current. 316. Effect of Currents of Charge and Discharge. — It will therefore be understood that when one wire of a differential relay is connected, as in the duplex apparatus, with a long insulated line having a considerable electrostatic capacity, while its other and opposing wire is connected with an artificial line principally made up of a rheostat destitute of electrostatic capacity, although the resistances of the two branches may be exactly the same, the initial charg- tential may be correctly taken to represent, the electrostatic charge in each case. A consideration of Fig. 154 will show that when the line is to ground at the distant end, as in duplex telegraphy, 75 per cent, of the aggregate charge of the line is accumulated upon the first half of it, and only 25 per cent, upon the second half. Therefore the currents of charge and discharge are three times as great at the battery end as at the ground end. This is upon the assumption that there is no appreciable loss through imperfect insulation. ing current in the main line will not be counteracted by a corre spending opposite effect in the artificial line, and hence a momentary false signal will be produced upon the home relay. So also, at the termination of the signal, when the line is detached from the battery and connected to earth at the home station, the electrostatic charge accumulated upon the line instantly flows back to the ground through the rear contact of the transmitter, passing through one wire only of the differential relay, and another false signal is produced. These false signals, occurring at the beginning and end of each true signal sent out from the home station, if not eliminated, would mingle with the received signals from the distant station, and utter confusion would be the inevitable result. 317. The Condenser. — This difficulty is overcome by connecting to the artificial line a device termed a condenser, which consists of a large number of sheets of tin-foil connected with the artificial line, interleaved with an equal number connected with the earth, and separated by sheets of insulating material, usually mica or paraffined linen paper. By arranging these sheets in separate sections, with proper electrical connections, a very large superficial area of tin-foil is exposed to inductive action, the actual extent of which may be varied at pleasure, so that the artificial line may be made to charge and discharge itself at the same instant, and to the same extent, as the main or actual line. The disturbing effects of the static charge and discharge upon the differential relay may thus be wholly eliminated.5 The condenser is inclosed in a wooden box and provided with a peg switch, as shown in Fig. 155, so that its electrostatic capacity may be varied as required. The manner in which the condenser is connected to the artificial line and to the earth is indicated at C in Fig. 149. At the common point 5, which is the terminal of the opposing or equating coil of the differential relay, are attached the rheostat X1 (the resistance of which is maintained equal to that of the main line), and the condenser C (the electrostatic capacity of which is also kept equal to that of the main line), which, by their joint action when properly adjusted, insure a perfect working balance to the apparatus under all conditions. 5 The credit of the idea of giving to the artificial line of the contraplex apparatus an electrostatic capacity corresponding to that of the main line, is due to Joseph B. Stearns, who successfully applied it on the lines of the Western Union Telegraph Company leading out of New York, in 1872. By this admirable application of a scientific principle, in a manner no less ingenious than simple, it is not too much to affirm that the commercial value of the aggregate telegraphic property of the world was more than doubled at a single stroke. FiG. 155. Adjustable Condenser of Artificial Line. 318. The Ground and Spark Coils.— It is necessary that the apparatus at the home station should always present an equal resistance to the currents coming from the distant station, so as not to overthrow the balance of the distant relay. This is effected by means of small rheostats X1 and X2 (Fig. 149), termed respectively the ground-coil and the spark-cot?, the resistance of the former being made equal to that of the latter, plus the internal resistance of the battery, and that of the latter being sufficient to prevent the polarization of the battery when momentarily short-circuited at the transmitter. 319. The Double-Current Duplex. — The principle of this apparatus will be understood by reference to Fig. 156. Double current or reversing keys are employed at each end of the line, each of which, when depressed, reverses the poles of its associated main battery without interrupting the circuit, and of course without chang- FIG. 157. Polar Relay ing the total resistance. Polar relays are also used, the peculiarity of which consists in the employment of polarized armatures, the construction and use of which have been explained in (200). The actual construction of the polar relay is shown in Fig. 157. The permanent magnetism of a polarized armature causes it to remain, by its own attraction, indifferently in contact with either pole of the electro-magnet, when no current is passing through its coils. If, then, we assume this electro-magnet to be differentially wound, and the armature normally at rest upon the rear contact so as to leave the local circuit open, it is obvious that whether the current sent out from the associated key be positive or negative, it cannot in either case, owing to the differential action, develop any magnetism in the cores, nor alter the position of the armature. The differential winding therefore produces the same effect with the polar as with the neutral relay. But at the distant station, the currents received over the line traverse one wire of the relay only, and hence the polarity of the core at that station is reversed each time the sending key is depressed or raised. When the key is down, a positive current passes, and the armature closes the local circuit ; when it is up, a negative current passes, and the local circuit is broken. In other words, the signals are produced by changing the polarity of the current, and not by changing its strength from zero to maximum, as in the single-current system. The actual construction of the transmitter employed is shown in Fig. 158. 320. The Quadruplex. — This apparatus may be regarded as a combination of the single-current and double-current duplex systems, adapted to be operated simultaneously in the same circuit. It has been explained that the polar relay in the double-current duplex (319) is actuated solely by changes in polarity, irrespective of strength, and in the single-current duplex (310) solely by changes in strength of current, irrespective of polarity. If then we place both a polar and a neutral relay in series in the same circuit, as shown in Fig. 159, it is evident that we may produce signals by moving the armature of the polar relay to-and-fro by means of alternate positive and negative currents, and in case these are not strong enough to affect the armature of the neutral relay, no signals will be indicated thereby. So also, if we maintain a constant polarity, and merely open and close the circuit, we shall produce signals upon the neutral but not upon the polar relay. 321. Principle of the Diplex. — Fig. 159 is a diagram showing a line having at one terminal station two keys, one single-current and the other double-current or reversing. The battery is also in two sections, one section B2 having three times as many cells and therefore three times as much e. m.f. as the other section B1. By tracing the connections, it will be observed that both sections of the battery are included in a loop, the terminals of which are reversed by the depression of the key K1, but that the greater section B2 of the battery only comes into action when the other key K2 is depressed. Operation of the Dip lex. Thus it is obvious that the e. m. f. of the current going to line will be four times as great when key K1 is depressed as when it is at rest, and that the key K2 when depressed serves to reverse whatever c. m. f. may be in circuit at the moment, whether of both sections or only the smaller section of the battery. In brief, the key K1 controls the polarity of the outgoing current regardless of its e. m.f., while key K2 controls the e. m. f. of the outgoing current regardless of its polarity. 322. Turning now to the receiving apparatus, we have in series, at the receiving end of the same circuit, a polar relay R1 and an ordinary or neutral relay R~. If the armature-spring of the neutral relay R2 be adjusted to such a tension that it cannot respond to the comparatively weak current of the battery B1, when unassisted by the battery B2, it is obvious that signals may be sent by reversing the smaller battery section by means of the key K1, which will actuate the polar relay R1, spond to each reversal, whether of the smaller or the larger current. 323. Operation of the Diplex. — Suppose a signal is being sent by the depression of key K2 ; both sections of the battery are in circuit on the line, causing the armature of the neutral relay R2 to be attracted. If now another signal be sent by the depression of the key K1, the full strength of the current traversing the neutral relay R2 will be rmersed. It is obvious that during this operation, no matter how instantaneously the reversal may be effected, there must be an interval during which no magnetism is manifested. The actual result of this is found to be that the neutral relay lets go its armature for an instant, and the spring begins to pull it away, but it scarcely has time to move before the opposite magnetism seizes upon it and restores it to its original position. This, if not guarded against, causes a slight break in the signal, known as the dip, which may nevertheless be eliminated by the aid of special devices. One of the most efficient of these devices is that of an intermediate local relay interposed between the neutral main-line relay and its associated sounder in the manner indicated in Fig. 160. When the armature of the neutral relay R falls off, the sounder S is not affected until it reaches its rear contact-point, when it closes the circuit of the local relay L, and the latter, also by its rear contact, breaks the second local circuit. When the main-line is closed the reverse action takes place. Thus the sounder can only be affected by a full opening of the main circuit, which shall continue long enough to permit the relay armature to reach in rear contact. A 324. The Diplex and Contraplex Combined. — Having an apparatus of this kind, capable of transmitting two sets of signals in the same direction at the same time without interference with each other, it is not difficult to understand that by applying a differential winding to both relays, polar and neutral, and by including both in the circuit of the main and artificial lines, precisely as in the case of the single-current and polar duplexes (310, 319), it becomes perfectly practicable to transmit two sets of signals upon a line in each direction at the same time,, and this is in fact precisely what is done in the case of the quadruplex.6 325. Quadruplex worked by Dynamo-Currents. — The quadruplex apparatus at the larger stations in the United States is now frequently operated by dynamo-currents, and it is probable that this method will in time become practically universal.7 The organization of the apparatus has been slightly modified from that illustrated in Fig. 159, to better adapt it to the conditions under which it is required to work. The principle will be understood by reference to Fig. 162. D1 and D2 represent two independent series of dynamos, such as hereinbefore described (304), one having its positive and the other its negative pole to the line. K1 is the polechanging transmitter and K2 the single-current transmitter, which, for simplicity, are shown in the diagram as keys, but which are in practice operated by electro-magnets, local batteries, and independent keys, as indicated in Fig. 149. When the apparatus is at rest, the current from the negative dynamo D3 traverses a resistance coil of say 600 ohms (which is inserted to avoid danger of injury to the instruments in case of an accidental short circuit) to the rear contact of the pole-changing key K1 ; thence through wire i (in which is included a rheostat of say 1200 ohms) to the point 2, where it divides into three portions ; the first portion going to the line and distant station, the second through the artificial line, including rheostat X, to the earth, and the third through the wire 3, the normally closed rear contact of the single-current key K2, and a rheostat of say 900 8 The method of diplex transmission here described, which forms the basis of the commercial quadruplex system, was invented in 1873 by Thomas A. Edison (see U. S. patent No. 162,633, APr- 27» ^75)- He also devised the apparatus described in (323), to overcome the principal obstacle in applying the method in quadruplex transmission. 7 The first successful application of the dynamo machine as a substitute for the voltaic battery in commercial telegraphy was made in 1879 by Stephen D. Field of San Francisco. (See his U. S. patents, Nos. 223,845, Jan. 27, 1880, and 243,698, July 5, 1881.) Detailefl descriptions of some of the more important dynamo plants have been published as follows : Western Union, New York, Operator and Electrical World, xiv. 225 ; same plant improved, W. MAVER, Jr., in Electrical World, xi. 67, 79 ; W. U. plant, Pittsburgh, W. MAVER, Jr., ibid, xii. 195 ; W. U. plant, Chicago, ibid^ xv. 173; Postal Tel. Cable Co., N. Y., ibid, xii. 65 ; Postal T. C. Co., Boston, ibid, xvi. 313. The plant of fifteen dynamos in the Western Union N. Y. central station does the work of more than 30,000 cells of gravity battery. ohms, to the earth. If for example, therefore, we assume the resistance of the main and artificial line to be 3600 ohms each, it follows from the law of distribution of currents in branch circuits (140), that 326. Distribution of Currents in Quadruplex Apparatus. — If now the key K2 be depressed in order to send a signal, a direct connection will be formed between key K1 and the point 2 through wires 5 and 3, shunting the i2oo-ohm coil in wire i. At the same time the wire 4 will be opened, and the whole current will divide at the point 2, half going to the main line and half to the artificial line. It follows, therefore, that with the several resistances in the ratios shown, the current sent to line by the key K1 when key K2 is depressed will be three times as strong as when the latter is raised, and this will be equally true whether the current sent by key K1 be positive or negative. 327. A computation of the effects of the several resistances will also show that when an arriving current reaches the point 2, the resistance which it has to encounter in passing thence to the ground is the same, whether the key K2 be depressed or raised. When the key is depressed, the resistance is only that of one or the other of the 6oo-ohm coils between the key K1 and the dynamos ; when raised, it is the joint resistance of one coil of 600, plus the coil of 1200 (a total of 1800), in one branch, and the coil of 900 in the other branch, the joint resistance of the two being 600, the same as in the first instance. The relays R1 and R2 at each station, being both differential, are not affected by outgoing currents, whatever may be the strength or the polarity of such currents. 328. Practical Management of the Quadruplex. — Skill in the management of an apparatus of so much complexity as the quadruplex can only be acquired by experience and careful study. Only a few hints can be given here.8 As a preliminary to these suggestions, an. explanation of certain technical terms which have come into use with the apparatus is necessary. key, the neutral relay, and their attachments. The tap-wire is the intermediate wire which divides the battery into two unequal portions, usually termed respectively the long end and the short end. (See Fig. 159.) The resistance which is inserted to compensate for the internal resistance of the battery is called the ground-coil. A resistance x, Fig. 162, is also placed between the condenser and the differential s A great amount of information of value respecting the history, theory, and practice of quadruplex telegraphy may be found in a series of articles by WILLIAM MAVER, Jr., in Electrical World, xi. 254, 266, 280 ; and in a subsequent discussion by FRANCIS W. JONES, ibid, xi. 290, 330, xii. 276; W. MAVER, Jr., ibid, xi. 305, xii. 231 ; CLARENCE L. HEALY, ibid, xi. 292 ; THOMAS HENNING, ibid^ xi. 330 ; H. W. PLUM, ibid, xi. 316. See also F. W. JONES : The Quadruplex, Journal Am. Electrical Soc., i. 16 ; F. L. POPE: Quadruplex Telegraphy, The Telegrapher, xi. 271. discharge of the condenser, in correspondence with that of the line. The proportion between the long and the short end of the battery varies in practice with the length of the line. On lines of 100 miles or less the division is usually equal, or, as it is termed, 2 to i ; on a line 350 or 400 miles, it may be with advantage as much as 4 to i. 329. Adjustment of the Apparatus. — The following method of procedure has been recommended by experienced operators, though it is proper to say that some difference of opinion exists in reference to the minor details of adjustment. First. Instruct distant station to "ground." He will then put the line to ground through his battery-compensation resistance or ground-coil. Both stations should assure themselves that the resistance of the ground-coil is equal to that of the battery. Second. The line being to ground at both ends, proceed to centre the armature of the polar relay. When centred, it should remain indifferently in either an open or closed position of the local circuit as placed by the finger. Third. Switch in the home battery, and vary the rheostat resistance in the artificial line until the polar relay can be again centred. If disturbing effects from foreign currents are felt, it may not be possible to do this accurately. In such case, approximate it as nearly as possible. may assist in adjusting the polar armature. Fifth. Instruct distant station to close both keys, thus sending full current to you. Close your No. 2 key ; send dots on your No. i pole-changer, and alter the capacity of your condenser until its effects on the home polar relay are eliminated. This condition is termed the electrostatic balance. ness of the adjustments as follows : Instruct distant station to send dots on No. i and words on No. 2. While this is being done, alternately open and close both keys at the home station. If both sets of signals from distant station come distinctly under all circumstances, the balance is obviously correct. The same test should be repeated by the distant station, in order to ensure an accurate working adjustment. In the above test, if the sending on No. 2 side should fail to come well, instruct distant station to hold No. i key open for a few seconds, and then closed the same length of time. If the signals come imperfectly in both cases, it indicates that the contact-points is the proper tool to use for this purpose. If the dots on No. i fail to come well at the same time with the writing on No. 2, instruct distant station to alternately open and close No. 2 key at intervals of a few seconds ; the trouble may usually be traced to defective contacts upon the single-current transmitter, provided the balance has been properly attended to. It should not be forgotten that a change of weather which is sufficient to affect the insulation of the line, may necessitate a readjustment, to a greater or less extent, of both the rheostat and condenser balance of the quadruplex. Both the line resistance and the electrostatic capacity are diminished by a defective state of insulation. The difficulties which may arise in the operation of a quadruplex apparatus are of such various character that it would be quite impossible to enumerate them in detail. Those which have been referred to are among those most liable to occur under ordinary circumstances. 3290. Repeaters for Multiple Telegraph Systems. — Notwithstanding the apparent complexity of the duplex and quadruplex apparatus, the arrangement of repeaters in connection with them is a very simple matter. It is only necessary to include the electro-magnet which works the transmitter of one line of communication in the same local circuit with the receiving apparatus of another line of communication. This facility of adaptation of repeating devices gives great flexibility to the system, and enables it to be employed for special service in a great variety of ways. Thus, for example, a single wire might be used as a duplex between New York and Boston, New York and Hartford, and Hartford and Boston. The local circuits of the transmitter and of the receiver in a main office may be extended through several branch offices in the same city, and thus all these branch offices may exchange messages directly, either with a distant main station, or with any one of a similar group of branch offices in the distant city. The limits of the present work will not permit a detailed description of these various applications of the system, with their numerous modifications, but the general principle will be readily comprehended by those who have made themselves familiar with the apparatus on which they are based. 330. Object of the Tests. — Telegraphic lines, from their exposed situation, are peculiarly subject to interferences and interruptions from various causes, and hence one of the most important duties of an operator is to familiarize himself with .the nature of these disturbances, so that their locatibn may be quickly determined and the proper measures taken for their removal. This is effected by an experimental investigation, technically termed testing. Another object in testing is to examine the electrical condition of the wires at stated intervals, and thus detect incipient faults before they become serious enough to cause interruption of the service. interruption may be classified as follows : (0) Disconnection or Break. — The continuity of the circuit is interrupted. A break may give rise to three different conditions : (i) When neither of the broken ends is in electrical connection with the earth; in this case the circuit is wholly interrupted so that no current can pass ; (2) when one end is in connection with the earth ; in this case there is no current on the portion of the line which is disconnected from the earth, but more or less on the other portion • and (3) when both ends are in connection with the earth, in which case there will be more or less current on both sections of the line. (b) Partial Disconnection, or Resistance. — This fault may arise from unsoldered and rusty joints in the line-wire ; from loose connections in the offices, or about the instruments, switches, and batteries ; or from a defective or insufficient contact between the earth-plate and the earth. (c) Escape. — Leakage from the line to the ground arising from defective insulation generally, or specifically from the line getting into contact with trees, wet buildings, etc. When an escape is so serious that it is impossible to work past it, it is called a dead ground. Testing for Disconnection. two or more wires, so tli.it current passes freely from one to the other, is termed a metallic cross. Sometimes parallel wires on the same supports swing to and fro in the wind, occasionally touching each other, and causing an intermittent disturbance termed a swingingcross. When only a portion of the current passes from one wire to the other, through defective insulation, wet cross-arms or the like, the effect is termed cross-fire, or sometimes weather-cross (248). A defect in a ground wire or plate which serves as a common terminal for two or more lines, produces an effect similar to that of a metallic cross. This difficulty not infrequently arises from the removal of a meter in the line of a gas-pipe which is used as a ground connection for the wires (210). interrupted, the armature of every relay in the circuit will fall off. In such case, the operator at each way-station should immediately proceed to test the line by connecting his ground to the line, first on one side, and then, if necessary, on the other, as has been explained in a previous chapter (278). If either connection closes the line, the interruption is on that side, for the circuit of the opposite terminal battery is completed through the ground in place of the interrupted wire. If the ground-wire gives no current on either side, it is most probable that the trouble is in the testing-station, though it may be that the ground connection is defective. Each operator should first assure himself by a careful examination that the fault is not in or about his own apparatus.1 Having ascertained the direction in which the difficulty lies, he should at once report the facts to the terminal station at the opposite end of the line. 1 An easy and expeditious way of doing this is to open the key, and then slightly moisten one finger of each hand and touch lightly the binding-screws by which the line-wires enter the switch. If the break is within the office a current will be perceived by the touch. Fig. 163 represents a line with four stations, A, B, C, and D. If, for example, the line be interrupted by a break at JFt two operative circuits may be formed by putting on the ground-wires at B and C, as shown in the figure. A can work with B, and C with Z>, notwithstanding the break between B and C. 333. Disconnection is usually caused either by the breaking of the line-wire or else by the careless leaving open of the switch of a key. Other less frequent causes are wires loose in their binding-screws (a defect peculiarly liable to occur in railway-station offices, on account of the continual vibration caused by the passage of trains), defective switches, and breakage of the fine copper wire in and about the relay. Sometimes the latter is burned in two just where it enters the helix, by the action of lightning. 334. Testing for Partial Disconnection.— It is somewhat difficult to locate this fault by testing merely with a key and relay. It is liable to be of an intermittent character, which by no means tends to lessen the difficulty. In case of this or any intermittent fault, the best plan is to cross-connect, where it can be done, by interchanging the defective line with a good one at the terminal and FIG. 164. Test for Intermittent Fault also at some other station, as in Fig. 164. If, for example, the fault is at F on No. 2 wire ; by cross-connecting at A and also at B, as shown, the fault will shift to No. i, showing it to be between the two points where the wires were to have been interchanged. If it were beyond B it would have remained on No. 2 circuit. In the latter case, put the wires straight again at B, and cross-connect at C and so on, station by station, until the fault shifts to No. i, which proves it to be between the two last stations. 335. Testing for Escape. — Call the stations up in rotation, beginning with the most distant one, and instruct each one to open his key for say ten seconds. When any station beyond the point of escape is open, a weak current will nevertheless pass to line through the home relay, the circuit being partially completed through the ground by the fault. For example, in Fig. 165, assume that terminal station A is testing. When the key is open at C or D a current will FIG. 165. Test for Escape. fault is located, from the fact that it cuts off or perceptibly weakens the current from the terminal battery in that direction, when tested with the ground-wire by the aid of the sense of feeling in the finger or tongue. 336. Testing for a Cross. — In case a cross is suspected to exist between two wires, as for example No. i and No. 2, instruct the most distant station to open No. i, and send dots on No. 2 wire. Then open No. 2 at your own station, and if the dots sent on No. 2 at the distant station are received on No. i, the wires obviously must be crossed. Some care is necessary not to be deceived by cross-fire, due merely to imperfect insulation, and not to actual contact between the wires. If the wires are in actual contact, the dots or signals will come nearly as strong on one wire as on the other. Next, instruct the distant station to leave No. i open. Open it at the home station also. No. 2 will now be free from interference, and station^ maybe communicated with upon it without difficulty. Commencing at the most distant station, call them in succession, and instruct each one in turn to send dots on No. 2. If the dots come on both wires, the cross is between the home station and the sending station, but if upon No. 2 only it is beyond the station sending. Each operator along the line should be instructed, while sending dots on one wire, to open the other wire, if practicable. 337- Principle of the Cross Test. — Figures 166 and 167 will explain the principle of this test. A two- wire line is represented having four stations, A, B, C, and D. Assume the operator at A to be testing for a cross which is located between B and C. In Fig. 1 66, No. i is open at station C and No. 2 is open at station A. If C sends dots on No. 2 the current will pass over to No. i at the cross, as indicated by the arrows, and the dots will come on the No. i instrument at A, showing that the cross is between A and C. In case C is not able to open No. i, the result will evidently be the same, provided it remains open at D. Now, if C closes both wires and B opens No. i, and writes dots on No. 2, as in Fig. 167, B cannot work when No. 2 is open at A, as both wires are open, one at A and the other at B. With both wires closed at A, the dots which B sends on No. i will reach A on No. 2, the current from F going over both the wires to the cross, and from thence to A on No. 2 alone. Thus the cross is definitely located between B and C. 338. A convenient and expeditious method of testing for crosses, in offices where there are a considerable number of wires, is for the operator to station himself at the switch with a test instrument, as shown in Fig. 139. When any station has been instructed to send dots on some particular wire, the testing operator can detect them by placing one finger upon the ground-wire and the other upon the line-wire to be tested, or its corresponding bar upon the switch. In wet weather, however, this method of testing is sometimes attended with much uncertainty, as it is extremely difficult to distinguish by this means between the effect of a metallic cross and those due to the leakage from wire to wire through imperfect insulation. The Wheatstone Bridge. 195 339. When a cross is found to exist between two lines, the one having the largest number of offices, or for other reasons the most available for business, should be cleared. The remaining wire can then be utilized for a considerable portion of its length, by instructing the stations nearest the cross in each direction to open the mainline wire at the switch, on the side towards the cross ; ground the other side, and ground the line in the other direction. This will enable the second line to be utilized in two sections. 340. Testing by Quantitative Measurement. — The tests which have been thus far described are such as may be made by the ordinary apparatus employed for the transmission of messages. They serve merely to roughly indicate the nature of the difficulty when it is serious enough to appreciably interfere with correspondence, and to determine between which two neighboring stations it is situated, but for accurate work more refined methods are necessary. Galvanometers and rheostats are the most essential instruments employed for this purpose, and the results are deduced by computation from actual measurements, made upon the principles which have been explained in Chapter IV. termed, current. 341. The Wheatstone Bridge. — This apparatus consists of three sets of resistance coils, a galvanometer, a battery, one or more keys, and the necessary connections.- Its principal use is to measure resistances, which may be done by its means with great convenience and accuracy, usually from o.oi ohm up to 1,000,000 ohms. The theoretical arrangement of the bridge is shown in Fig. 1 68. It consists of four resistances, a, b, d, and x, arranged in a parallelogram, the galvanometer being connected across one transverse diameter, and the battery across the other. When the values of the four resistances are so adjusted in relation to each other that the current from the battery produces no deflection upon the galvanometer, it is certain that these several values must then bear a 1 This ingenious and useful system of electrical measurement was first described by SAMUEL HUNTER CHRISTIE, in Phil. Trans. R. S., 1833, 95-142. Its importance remained unappreciated until attention was directed to it by Professor CHARLES WHEATSTONE, in a lecture before the Royal Society in 1843, entitled " An account of several new Instruments and Processes for determining the Constants of a Voltaic Circuit." Phil. Trans. R. S., cxxxiii. 303-327. Although full credit was accorded to Christie by Wheatstone for his admirable device, electricians have ever since persisted in calling it the Wheatstone Bridge, and it seems probable that it will always continue to be known by that name. FIG. 168. Principle of Wheatstone Bridge. Forces and Resistances.— In performing the operation of testing, with equal resistances in the branches a and b of the bridge, the most trustworthy determinations are reached by preserving a due relation between the value of the e. m.f. employed, the branch resistances a and b, and the unknown resistance x, which is to be measured. Hence when the unknown resistance is Between I and 100 units, a and b should be 10 ohms each ; e. /»./., i volt. Between 100 and 1000, a and b should be 100 ohms each ; e. m. f., 10 volts Between 1000 and 10,000, a and b should be 1000 ohms each ; c. ///. /., 100 volts. FIG. 169. Fall of Potential in Arms of Bridge. a circuit divides into two or more branches, the potential of each branch must necessarily be the same. If, at any other point, any two or more of these branches are again joined, the potentials must again be the same. In the bridge, therefore, if we assume the potential at the point where the current first divides to be say 100 volts, and at the point where they meet again or are connected to the earth to be o, let each circuit be assumed to be divided into 100 equal spaces, as indicated in Fig. 169. If now a wire be connected across from one of the branch circuits to the other, connecting the point 50 FIG. 170. Wheatstone Bridge Apparatus. to 50 or 75 to 75, or, as shown in the figure, 25 to 25, or between any other two points whatever having the same potential, no current can flow from one point to the other through the wire, because there exists no difference of potential between its ends ; but if, on the other hand, the wire is connected between any two points of different potential, as, for example, from 50 to 25, a current will necessarily flow through it (143), and a galvanometer placed in the wire will be deflected. When, therefore, the needle is not deflected, the proportionality referred to in (341) must always exist between the resistances of the four sides of the bridge.3 ern sets of apparatus, such as that shown in Fig. 172, the galvanometer, rheostat, branch-coils, contact-keys, and five cells of battery, with the necessary connections, are all put up in a portable mahogany box, with lock and handle. A lifter is provided for raising the needle from its pivot when the apparatus is not in use. 345- Galvanometer for the Wheatstone Bridge.— In selecting a galvanometer for any particular purpose, one having a few turns of thick wire, and small resistance, is most suitable for measuring small resistances, while for long circuit or a great resistance of any kind, a galvanometer of many turns of thin wire should be selected. Fig. 173 shows an excellent type of galvanometer for use in the bridge as well as for general purposes. It has an astatic system of needles,4 suspended by a delicate silk fibre, and is fitted 3 The above explanation has been adapted from LATIMER CLARK : Electrical Measurement, p. 85. The student desiring to acquaint himself thoroughly with the theory of the bridge may, with advantage, consult also F. JENKIN : Electricity and Magnetism, p. 241 ; H. R. KEMPE : Handbook of Electrical Testing, p. 166 ; SILVANUS THOMPSON : Elementary lessons on Electricity and Magnetism, p. 318. FIG. 172. Wheatstone Bridge Apparatus, with Galvanometer and Battery. 346. To Measure the Conductivity Resistance of a Telegraph Line. — Have the remote end of the line put to ground, taking care that no relays are left in circuit. Connect the home end stronger than the other, so that the pair has a very feeble tendency to place itself in the magnetic meridian (86 6). Such a system is capable of being deflected by a very weak current, and hence is used in th2 construction of the more delicate types of galvanometers. of the line under test. 346^. Conductivity Resistance by Loop Method.— A more accurate method of making conductivity tests, which is available whenever there are three or more parallel wires available between the same points, is the loop test. If we suppose the wires to be Nos. i, 2, and 3, they are looped together in different combinations at the distant station, and the resistances of the several loops taken in succession, one end of the loop under test being connected to C and the other to E, as in Fig. 171. For example, suppose the resistances to measure as follows : If we deduct from this result the total of each pair of looped wires in succession, the remainder in each case must be the resistance of the wire not in the loop. Thus : 9780 — 6180 = 3600 for No. i wire. 9780 — 6830 == 6830 for No. 2 wire. 9780 — 6550 = 3230 for No. 3 wire. Conductivity tests may also be made with sufficient accuracy fo? most purposes, and with great convenience and facility, by means of a properly constructed voltmeter. See (369). 347. Earth Currents. — In making conductivity tests with the distant end of the line to ground (346), interference is sometimes caused by earth currents, which flow through the wire, and aid or oppose the testing current, as the case may be. When these are tolerably steady and not too strong, their effect may be eliminated by making measurements with both a positive and a negative current and taking the mean of the two results. Sometimes, however, these earth currents are so strong that an accurate measurement cannot be made, and the loop method (3460) must be resorted to. 6 Care should be taken in all cases, when finally closing the circuit by the second or galvanometer-key, to first make very short contacts or " taps," just enough to indicate the direction of the deflection of the needle, until the coils are nearly adjusted to a balance, otherwise much time will be needlessly lost by the oscillations of the needle. 348. Measurement of Resistance of Ground Plate at Distant Station. — The principle of this measurement is the same as that last described. Two lines are necessary ; the earth takes the place of the third line. For example, suppose we have : Half the sum of which is 6575, from which deduct loop resistance of Nos. i and 2, gives 25 ohms as resistance of ground. The resistance of a ground plate ought not to exceed 10 ohms. 349. Measurement of Insulation Resistance of a Line. — In making this test, the connections at the home station are the same as in the conductivity test (346) ; the line is open or insulated at the distant station, instead of being to ground. In most cases, the insulation resistance will exceed the amount of resistance available in the E A side of the bridge. In this case the resistance in A B (/>) must be made greater than that in B C (a). For example, it may be 10 in B C and 100 or TOGO in A B. In this case, when the balance has been obtained, the amount unplugged in E A (d) must be multiplied by 10 or by 100, as the case may be, in order to obtain the correct resistance. It will be observed that under these conditions, the ratio of the resistances in the different parts of the bridge remains unchanged. 350. Location of the Position of a Ground.— When the fault is a dead ground, which is not often the case, it is a very simple matter to locate it. For example, if the line were 250 miles long, and from previously recorded measurements its conductivity was known to be 3250 ohms, or 13 ohms per mile, and the resistance measured through the fault was 1287 ohms, then the distance from the testing station would be 1287 -5- 13 = 99 miles. 351. Location of the Position of an Escape. — This is one of the most common cases which arise in practice. If no other than the defective line is available for the measurement, the process presents some difficulties, for the reason that the resistance of the fault is usually variable. If we have, for example : Varleys Loop Test. 203 finally subtract this result from (3). In the above case, this would give the resistance of the conductor to the fault as 1500 ohms. While this method is theoretically accurate, it will not do to depend too much upon it in practice, for the reasons given. 352. Method of Double Measurement.— Let two measurements be made, one from each end, the opposite end of the line being open. Suppose the fault the same as in the last case. By records and measurements we have, — 353. The Loop Test. — When a good wire is available between the same points as the defective wire, this method may be made to give extremely accurate results in the hands of a careful operator. The arrangement of the connections, the method of making the measurements, and the computation of the result are precisely the same as in the method described for measuring a distant ground in (346). If the resistance of the fault is considerable, care should be taken to employ sufficient battery-power to get decided deflections on the galvanometer. The loop should be made at the nearest station available beyond the fault. third good wire is not available, connect one of the crossed wires to C and the other to E of the bridge. Make one measurement of the loop through the cross with both lines open at nearest available station beyond, and another with the same wires looped at that station. If the two measurements are approximately the same, the number of ohms in the loop divided by 2 and converted into miles will give the distance of the cross from the testing station. If the lines are of different length, owing to the routes being different, allowance must be made for the fact ; also, if the wires are of different conductivities per mile. 356. When the two measurements differ considerably, showing that the cross offers more or less resistance, the above test would give a result in excess of the real distance. In such case the following procedure maybe adopted. In Fig. 177, suppose wires No. i and No. 2 to be crossed at X. Shunts of Galvanometers. 205 Deducting (3) from the sum of (i) and (2) gives 5000, which divided by 2 gives 2500 ohms, as resistance of No. i wire from A to X. The distance on No. 2 wire may be found, if desired, in the same way. FIG. 177. Distance Test for Cross. 357. When a third wire in good order is available, the most convenient as well as the most accurate method of locating a cross, is to ground either one or both ends of one of the crossed wires and make the other crossed wire into a loop with the good wire. The cross can then be treated as a ground, and located by one of the loop tests heretofore given in (353) and (354). 358. To Locate a Bad Joint or Abnormal Resistance. —It sometimes happens that a line gives a much higher resistance than it should do, according to computation or by previous measurement. In such cases a bad joint may be suspected. To locate it, instruct a station midway of the line to put on ground. Take a measurement through first half of the line and this ground, the distant end being open. This will show whether the fault is in the section measured or beyond. Repeat the test to another station in the middle of the defective section, and so on until it has been fixed between two sections. 359. Measurement of very High Resistances.— The highest resistance which can be measured by the Wheatstone Bridge apparatus, described in (344), is i megohm, or 1,000,000 ohms. This is a sufficient range to cover most of the requirements ordinarily met with in practical telegraphy, but in testing insulators, or the insulation resistance of very short sections of out-of-door line, it is often desirable to be able to determine much higher resistances. The method of proportional deflections is usually resorted to in such cases. A galvanometer having a coil of a large number of turns of very thin wire and a delicately suspended needle (345) is most suitable for the purpose. 360. Shunts of Galvanometers. — The galvanometers for this work must be provided with shunts ; these are short coils of .wire, arranged to be connected or bridged across the terminals of the galvanometer, and are usually marked (to indicate their multiplying power) i- 10, i-ioo, and in very delicate instruments usually i-iooo also. FIG. 178. Shunt Box for Galvanometer, The first shunt coil has 1-9, the second 1-99, and the third 1-999 of the resistance of the galvanometer coil. They are made of copper wire, that they may be affected by temperature in the same ratio as the galvanometer coils. Fig. 178 shows an arrangement much parison with the resistance to be measured, and hence the force of the current acting upon the needle may, without sensible error, be regarded as proportionate to the e. m.f. of the battery. First, connect the galvanometer G in circuit with a large known resistance R (say 10,000 ohms) and a single cell E, whose e. m.f. is known, as, for instance, a gravity cell (9). If the deflection exceeds 12°, reduce it to a point below that figure by the ^ use of the proper shunts.6 The arrangement of the connections for performing this operation, which is termed taking the constant of the galvanometer, is illustrated in Fig. 179. Second, remove the shunt and the resistance R, and having replaced the latter by the unknown resistance to be measured, add a sufficient number of cells of the same kind (in series) to produce a convenient deflection, not exceeding 12°, as before. The result is found by simple rule of three, as in the example given in the next paragraph. 362. Measurement of Resistance of Insulators.— Mount a set of say 10 insulators, I, Fig. 1 80, upon a suitable frame out of doors, exposed to rain under the same conditions as if in actual service. Bind a line-wire to the whole series, and connect this with one terminal of the galvanometer G, the other terminal of « The reason for this procedure is, that above this point the angles of the deflections cease to be proportional to the strength of the currents producing them. (Compare table of tangents, p. 55.) Measurement of Internal Resistance of Battery. 207 galvanometer to zinc pole of battery E, and the copper pole of battery to ground. Suppose that with the particular galvanometer msed, the following results are obtained, the weather being very wet : cluded battery and galvanometer, is doubled, the quantity of the current flowing through it is halved ' ; and hence if the indications of the galvanometer be proportional to the strength of current, its deflection will also be halved. If a tangent galvanometer (96) of known resistance is at hand, connect it with a plugged rheostat in the circuit of the battery to be measured. Reduce the sensitiveness of the instrument by a shunt (360), if necessary, to bring the deflection as near 60° as possible, and note the corresponding tangent of the deflection as given in the table, p. 55. Unplug resistance until the tangent of the deflection is halved, showing that the total resistance has been doubled. Deduct the resistance of galvanometer and connections from the added resistance ; the remainder is the resistance of the battery. Do not forget that the shunt, when used, diminishes the resistance of the galvanometer as a part of the measured circuit. 364. (2) If the resistance of the galvanometer is unknown, a modification of the Wheatstone bridge may be used. Make the connections as in Fig. 181. Connect the terminals B' and E by a short, thick wire. The left (galvanometer) key is permanently depressed. Touch the right-hand key and adjust resistance A E (d) until the needle remains at rest (it will not be at zero). It is neces- sary to shunt the galvanometer in this test. If the resistance in A B (a) is equal to that in A B (£), the amount unplugged in A E is equal to the resistance of the battery. In any case, by proportion, mined in the same way. Make B C (a) not more than one-tenth of the probable resistance of galvanometer, and make A B (b) not less than ten times the same, but not so high as to carry A E beyond the range of the rheostat The least possible value of B C with an ordinary bridge set would be 10 ohms. A smaller resistance might be extemporized from a piece of wire, if necessary. 366. The Differential Galvanometer.— This instrument is primarily designed to show the difference in strength between two currents. The coil is wound throughout with two wires, equal in length, resistance, and number of convolutions, so that the same current in each will have a like effect upon the needle. The two wires are sometimes formed into a tape by plaiting together the silk with which they are covered. If, therefore, two equal currents traverse the respective wires in opposite directions, the needle will not move. If one current be stronger than the other, the needle will be moved by the stronger current with a force due to the difference in the strength of the two currents. This instrument was formerly much used to measure resistances by comparing them with standard resistance coils, but has now been practically superseded by the Wheatstone bridge (341). 367. Testing for Insulation by Received Currents.— This system of testing offers many advantages over that hereinbefore referred to (340) for the daily examination of telegraph lines. The current from a testing battery, of a definite and approximately uni- Testing for Insulation by Received Currents. 209 form e. #/./., is sent at a stated time through the different lines, or sections of lines, and the volume of current, as indicated by a tangent galvanometer such as that shown in Fig. 182, or by an ammeter (369) at the receiving end, is registered. It is evident that the strength of the received current will be greater or less as the insulation is better or worse, and hence if the e. m.f. of the battery be constant, the volume of the received currents as observed from day to day will give an accurate knowledge of the condition of the lines. The normal resistance of each line is known from the stated conductivity tests, and so if the currents be sent from a battery of known e. m. f. it is only necessary to divide the latter amount by the former to know at once the maximum current which can possibly be received through any wire. For example, if a battery of 50 cells be used on a circuit of 2500 ohms, then This may be regarded as the standard current of that circuit, and the greater the leakage the greater will be the diminution of the current below that standard. Tables may be made for convenient reference showing the normal current of each line. Special faults are of has been revealed by the procedure above described. 368. Use of the Voltmeter and Ammeter in Telegraphic Testing. — Since the general introduction of electricity in lighting and power service, a new class of instruments for the measurement respectively of potential and current, known as voltmeters and ammeters, have been brought to great perfection, and are now frequently employed with advantage in telegraphic work. Much time is saved in making readings and computations, as a simple inspection of the indication of the pointer on the scale at once gives the result in volts or amperes. The pointer comes to rest promptly, so that a reading dan be made almost instantaneously. amperes, which may be read by inspection to a single mil-ampere.7 Another type, which is adapted to perform all the measurements ordinarily required in a large telegraph station, is provided with several scales ; one of a single volt, which may be read to .001 volt, for determining the potential of a single cell ; another of o to 500 volts (which can be read to single volts or half volts), for taking the potential of a large number of cells when connected in series in a single battery ; another of i ampere (which can be read to milamperes) for determining the strength of currents. Some are made 7 The construction of the voltmeter and ammeter are simLar, the difference being in the length and thickness of the wire in the deflecting coil, which is made long, thin, and of great resistance in the voltmeter, and comparatively short and thick and of small resistance in the ammeter. Two or more coils of different lengths may be fitted to the same instrument, as in a galvanometer, giving different grades of sensibility. The Weston Ammeter and Voltmeter. 211 with a coil of precisely 100 ohms resistance, giving a full scale deflection with i volt. Such an instrument is very convenient for measuring line resistances. For example, with 100 volts the resistance in circuit required to bring the pointer to the upper division of the scale would be 10,000 ohms, and hence by pointing off two decimal places any resistance in ohms in the circuit may be determined by direct reading from the scale, in the same manner as volts. The Weston instruments are particularly well adapted for all current measurements usually performed with a tangent galvanometer (102). They are not only, for most purposes, more accurate, but are far more convenient, as they may be placed in any position, and are in no wise affected by the neighborhood of masses of iron or of foreign electric currents. No time need be lost in leveling, adjusting, or waiting for the needle to settle, while the convenience of being able to read off the results directly without calculation is very great. Another and a very important advantage is, that the tests may be made with the same current which is employed in the ordinary operation of the circuit Tests for resistance, especially, not unfrequently give very fallacious results, when made, as is often the case, current. 370. Recording Tests of Conductivity and Insulation.— The forms of returns for line tests adopted by the Western Union Telegraph Company are given on pp. 212, 213. When the tangent instrument is used, the constant (361) is written in the upper right-hand corner of the sheet. One horizontal line is appropriated to each separate wire tested. The headings sufficiently explain entries to be made in the several columns. When the tests are made by the bridge apparatus, the results are entered directly in the resistance columns, but if with the tangent instrument, these are computed and filled up at the electrician's office in New York. The same observations apply to the insulation form. The record of the wet and dry bulb thermometer is important, as it enables the percentage of moisture in the air to be determined and its effect upon the different kinds of insulation to be compared and studied. By inspecting and comparing these sheets, as returned from the various testing offices, the electrician's department is kept fully informed of the electrical condition of the lines in all parts of the country. The system of stated reports was instituted by Lefferts, of the American Telegraph Company, in i863,8 and has resulted in a vast improvement in the efficiency of the service. 8 LEFFERTS (MARSHALL), born January 15, 1821, in Bedford, now part of Brooklyn, N. Y. In early life he was a civil engineer and was employed in laying out the city of Brooklyn. Subsequently he became a successful merchant in New York City, and a prominent militia officer. In 1849 his marked scientific tastes led him to become interested in telegraphy. Entering into the new enterprise with the energy and zeal which were among his most notable characteristics, he organized and became the president and manager of a range of lines operating the Bain electro-chemical system, extending from New York to Boston and Buffalo. Legal complications in connection with patents eventually led to a consolidation of these lines with those controlled by the Morse patentees, in consequence of which he resumed for a time his manufacturing and mercantile business. In 1860 he was appointed engineer and executive manager of the American Telegraph Company, which under his administration became one of the most popular and successful telegraph organizations that ever existed on this continent. He retained this position until the consolidation of the American with the Western Union Telegraph Company in 1866, and subsequently occupied a responsible post in the united service until 1871. At this date he was elected president of the Gold and Stock Telegraph Company of New York, which position he held until his death. He possessed a most unusual organizing and executive ability, and while a strict disciplinarian, it afforded him genuine pleasure to discover and to reward meritorious service, even in the humblest capacity. His uniformly just and considerate treatment of his employees, no less than his genial and kindly spirit, insured the most loyal, enthusiastic, and diligent service from all. By a liberal system of advancement to the intelligent, the skillful, and the deserving, the standard of character and acquirements among the employees of the American Company was elevated to an extent to which later times have afforded few parallels. As engineer of this extensive organization, he labored unceasingly to place its service upon a permanent foundation befitting its importance and its high mission. He was the first to appreciate the importance of testing lines and apparatus, and it is to the standard ot excellence which he established that the commencement of the era of scientific telegraphy in America may be traced. Assuming in 1861 the administrative management of a heterogeneous assemblage of poorly built and ill-arranged telegraphs, equipped with a miscellaneous collection of apparatus of antiquated and unserviceable types, he five years later turned over to the Western Union Company 30,000 miles of wire, constituting perhaps the most complete, thoroughly organized, and efficient telegraphic system in the world. The influence of the reforms and improvements which were instituted during his administration will continue to be felt in the American telegraph service for all future time. He died suddenly, July 3, 1876, while on his way, as commander of a military organization, to participate in the celebration of the centennial anniversary of the Declaration of American Independence, in Philadelphia. 371. Formation of the Telegraphic Code. — The code of alphabetical and numerical signals employed in telegraphy, as devised by Vail in 1837,! is made up of various combinations of a small number of elements. In the so-called " Morse " code, as used in America, there are seven of these elements, viz. : (i) The dot; (2) theitasA; (3) \hzlongdash; (4) the ordinary space; (5) the letter-space; (6) the word-space; and (7) the sentencespace. It is important to remember that the value of the spaces in the code is as great as that of the dots and dashes. A common misconception exists in the minds of students that the telegraphic code consists exclusively of dots and dashes. The foundation of perfect telegraphic manipulation lies in the ability, which can only be acquired by careful observation and training, to accurately divide and subdivide time into intervals which are multiples of an arbitrary unit. 1 VAIL (ALFRED), born at Speedwell, near Morristown, N. J., September 25, 1807. In early life he became an apprentice in his father's Speedwell iron- works. After attaining his majority, he pursued a course of study and graduated at the University of the City of New York with the intention of entering the ministry, but in September, 1837, chancing to witness one of the early experiments of Morse with his crude telegraphic apparatus, his mind, naturally of a strongly scientific cast, was instantly fired with enthusiasm at the future possibilities of this marvelous invention. He became wholly absorbed in the enterprise, and persuaded his father, Stephen Vail, to furnish the means required to perfect, develop, and introduce the electric telegraph. Among the improvements in the apparatus and methods originated by himself, of the utmost practical value, were the register (269), which is to-day but little changed from the form he gave it in 1844, and the "Morse" alphabetical code (372), now in universal use in America. (See American Inventors of the Telegraph, Century Magazine, xxxv. 924, April, 1888.) The efforts of Vail in overcoming the numerous practical difficulties that beset the work of installing the pioneer telegraph line between Washington and Baltimore in 1844, were indefatigable, and it is to his genius, patience, and untiring diligence that the ultimate success of the enterprise was in no small measure due. The last ten years of his life were passed by him in comparative retirement, engaged in his favorite pursuits of science and literature. He died at Morristown, January 18, 1859- The American Morse Code. 372. The American Morse Code.— The complete code as now used in the United States and Canada, comprising letters, numerals, punctuation, and other signs more or less used, is given below : The arbitrary unit of time in this code, which, when written down, becomes a unit of length, is technically termed the dot ; an unfortunate name for this element, inasmuch as it conveys the idea of an inappreciable lapse of time, or of the transmission of a current of infinitely short duration. On the contrary, an appreciable time is required for the production of signals by electricity (315); in the magnetization of electro-magnets (195), and in the movement of clock-work. The formation of a dot, therefore, necessarily involves time. Assuming, therefore, that Handling the Key, 219 The old rule in transmission was to make the dash equal to 3, and the long dash to 6, dots. When the receiving was largely done by recording instruments this was a most necessary requirement, for a dot, and a dash equal to only 2 dots, might easily be mistaken for each other in reading by sight, but now that receiving by sound has become practically universal, this objection has lost its force, and by shortening the dashes a material gain in rapidity of transmission is effected without any corresponding disadvantage. 373. Learning the Code. — The student should first thoroughly commit to memory the groups of signs representing the letters of the alphabet, the numerals, and the principal punctuation points, viz., the/mW, the comma, and the point of interrogation. The remaining characters can be learned afterwards, as they will be little needed by the beginner. 374. Handling the Key. — The most approved manner of grasping the key, and one which has been employed by some of the most successful, experienced and rapid American operators, is shown in Fig. 185. Curve the fore-finger, but do not hold it rigid. Let the thumb press slightly in an upward direction against the knob. Keep the wrist well above the table. No better general1 direction can be given than that the key should be grasped, held, and controlled with the same flexible but perfectly controlled muscular action of the fingers, wrist, and fore-arm with which the skilled penman holds his pen. Carefully avoid tapping upon the knob of the key ; the raising spring should assist the upward motion of the key, but should never be permitted to control it. By constant drill, as hereinafter directed, the habit of making dots with regularity, uniformity, and precision must first be acquired ; then dashes, and lastly in order, group of clots and dashes, letters and words. If possible for the student to obtain a register (269), he should by all means employ it in his practice, for he will then be more easily enabled to observe and correct the faults in his own manipulation. In commencing, the habit should at once be acquired of making the dots like short, firm dashes. The student should learn to form the conventional characters accurately and perfectly ; speed will come in good time, but only as the result of constant and persistent practice, accompanied by a determination to excel. should first practice upon the above elementary principles. (1) Make dots with the key at uniform and regular intervals, until they can be produced with the precision of a machine, and of definite and uniform dimensions. The student will find this more easy, if at first he times himself by the beats of a watch or a small clock. (2) Next, make dashes, first at the rate of about one per second, which speed may be increased by degrees, as skill is acquired by practice, to three per second. Make the space interval between successive dashes as short as possible. If the upward movement which forms the space be made full, it cannot be made too quickly. directions. (4) This principle will be found somewhat more difficult to execute. The usual tendency is to make T too long, and L too short. Theoretically, the cipher is one-half longer than L, but in fact it is always made the same, as the practice has been found to occasion to separate the two elements too much. (6) The dash followed by a dot (N) is usually found to be somewhat difficult. Time the movement by pronouncing the word ninety, sounding the first syllable fully. Guard especially against the usual tendency to separate the elements by too great a space. 377. Exercises upon Code Characters. — Having become thoroughly familiar with the principles, the following exercises may with advantage be taken up in order : These should be practiced repeatedly until the correct number of dots in each character can be certainly made at every trial. A habit once formed of making the wrong number, usually one or two too many in the case of H, P, and 6, is almost impossible to eradicate. Guard especially against the objectionable habit of shortening or dipping the final dot, a vice which leads to innumerable and vexatious errors and misreading of signals. The faults to be particularly guarded against in this exercise are shortening or elongating the terminal dash, and separating the successive dashes by too great a space interval. The usual tendency to allow too much space between the dot and dash in the above letters may be overcome by forming them as by an elongation of the final dot in I, S, H, and P. G 7 Exc. J and K are usually considered the most difficult letters in the code. Avoid the tendency to separate J by a space into double N, and be careful that the dashes are of equal length. The numerals 7 and 9 require some care to ensure correct spacing. These are termed the spaced letters, and the utmost care and diligent practice are necessary in order to form them accurately. The ability to transmit the spaced letters with absolute correctness is the test of a strictly first-class sender. The space should be just enough in excess of that ordinarily used between the elements of a letter to enable the letters intended to be made to be distinguished with certainty from I, S, and H. The most usual tendency is to make the space too great, even in some cases as great as the space between letters. This is a most fruitful source of misapprehension and error, and too much pains cannot be taken to acquire and maintain correct habits in this particular. In transmitting words containing groups of two or more spaced letters, careful operators are accustomed to slightly increase the spacing between the successive letters of the group. Practice in transmission from miscellaneous manuscript is strongly recommended. The ability to read all kinds of copy ; good, bad, and indifferent, correctly at sight, is a most valuable one, and is not difficult to acquire by attention and experience. If the principles here laid down be firmly adhered to, the learner will find much reason for encouragement, not only at the rapidity with which he will master what at first sight appears to be a very difficult undertaking, but at the extreme accuracy with which he will be able to manipulate his instrument after a fair amount of practice. He must also carefully bear in mind that one of the most universal faults among those attempting to learn the telegraphic art, is that of going over a great deal of ground and learning nothing thoroughly. Reading by Sound. 223 378. Reading by Sound. — This art can only be acquired by constant and persevering practice, keeping in mind the principles above given. The lever of the telegraphic sounder makes a sound at each movement, the downward motion producing the heavier one. The down-stroke indicates the commencement of a dot or a dash and the up-stroke its termination. A dot makes as much sound as a dash ; the only difference is in the length of time or interval which elapses between the two successive sounds. Thus, if the recoil or up-stroke were absent, it would be impossible to distinguish E, T, and L from each other. 379. In learning to read by sound it is advisable for two persons to practice together, taking turns at reading and writing, and each correcting the faults of the other. The sounds of the code characters must first be learned separately, and then short words chosen, which must be written very slowly and distinctly and well spaced, the speed of manipulation being gradually increased as the student becomes more proficient in reading. After becoming sufficiently well versed in the art to read at the rate of twenty-five or thirty words per minute, further practice may best be had in copying with a. pen and ink (not with a pencil) from a sounder connected with a line employed in transmitting ordinary commercial and railway messages, in order that the student may familiarize himself with the technical usages of the lines, and the minute details of actual telegraphic business.4 380. A Parting "Word. — In conclusion, the student is warned against falling into the common error, which is not confined to telegraphy, of expecting great results from little labor. To become an expert sending and receiving operator requires a vast amount of time and patience, and the most unwearied application. Remember that whatever is worth doing at all, is worth doing well. It is seldom that a thoroughly competent operator cannot obtain immediate and remunerative employment, and it is probable that such will continue to be the case, however crowded the lower walks of the avocation may hereafter become. 4 Full explanations respecting the methods, regulations, and forms usually employed in the commercial, railway, and express service, in the forwarding and reception of messages, train orders, reports, etc., and much other miscellaneous information of like character useful to the student of telegraphy, may be found in the later editions of Abernethy's Modern Service of Commercial and Railway Telegraphy. A little work by T. J. Smith, on The Philosophy and Practice of Morse Telegraphy^ may also be consulted with advantage. Ammeter or amperemeter, the, 44, 61 ; use of in telegraphic testing, 210 ; Weston's portable, 211 ; advantages of for testing, 211. Batteries, composed of number of cells, 3. Battery, method of determining cost of maintenance of, 75 ; position of in closed-circuit system of telegraphy, 109 ; potentials within, 123 ; best position for on leaky line, 131, 132 ; internal resistance of, methods of measuring, 207. Breakage of battery jars, causes of, 10. Bridge, Wheatstone's, 195 ; theoretical arrangement of, 195 ; invented by Christie, 195; principle of illustrated, 196; best ratio of electromotive forces and resistances in, 196 ; actual construction of, 198 ; galvanometer for. 198 ; methods of making various tests with, 199-208. Cell, gravity, maintenance of, 14 ; dismantling of, 16 ; best adapted to closed circuits, 16 ; waste products of, 17 ; electromotive force of, 74 ; resistance of, 74. ture upon resistance of, 78. Cell, voltaic, Hill's, Callaud's, Minotto's, Thomson's, 17 ; Lockwood's. 18 ; Daniell's, 19 ; Edison-Lalande, 21 ; Grove's, 23 ; Bunsen's, 23 : rate of consumption of material in, 13 ; effect of continued action in, 13; various forms of, 17 ; general directions for care of, 20 ; how shown in diagram, 104. Circuit, open or broken, the, 12. Circuits, telegraphic, 102 ; open and closed, 102; diagram of, 104; essential characteristics of, 102; general considerations respecting, 109; working efficiency of, in ; distribution of potentials in, 120. raphy, comparative advantages of, 109. Closed-circuit system of telegraphy, 102 ; description of, 108 ; American modification of, 108 ; position of battery in, 109. mentary principles of, 219. Code, American Morse, 217, 218 ; alphabet and numerals of, 218 ; punctuation, etc., of, 218 ; best method of learning, 219 ; exercises with, 220. Compass, magnetic, 25. Condenser, construction of, 178 ; application of to duplex telegraph, 178 ; first applied by Stearns, 178 ; how shown in diagram, 104. Current, electric, formation of, n ; produced by magnetic held, 29 ; manifestations of in conductor, 35 ; effect of imperfect insulation upon now of, 127 ; direction of, how shown in diagram, $04. Currents, adaptation of electro-magnets to, 96 ; method of determining, 96 ; distribution of in quadruplex telegraph, 186. means of, 208. Curve, of ratio between magnetic attraction and distance, 90 ; of electrical dimensions in oxide of copper cell, 77 ; of resistance as affected by temperature in Daniell's cell, 79 ; of magnetization of soft iron, 85 ; of magnetic saturation, 85 ; of potentials in electric circuits, 121, 123, 124; of potential within battery, 125 ; of potential on leaky line, 125, 126, 130. ventional assumption, 12. Disconnection or break, conditions arising from, 190 ; testing for, 191 ; testing for at way station, 154 ; causes of, 192. Distance between magnet and armature, effect of upon attractive force, 89 ; experimental determination of, and tabulated results, 89, 90. Duplex, single current, 172 ; apparatus of, 172 ; circuits of, 173 ; artificial line of, 173; balancing of, 173 ; effect of currents of charge and discharge in, 177 ; ground and spark coils of, 179 ; double current, description of, 180. in telegraphy, 167. Dynamo-electric machine, the, 32 ; theory of explained, 32 ; diagram of, 104 ; field of, 168 ; commutator of, 168 ; brushes of, 168 ; characteristics of, 169 ; Edison's, 168 ; arrangement of in potential series, 169; positive and negative series of, 170 ; capacity of, 171 ; shunt coils of, arrangement of in telegraphy, 171. Edison-Lalande oxide of copper cell, 21 ; electromotive force and resistance of, 76 ; duration of, 76 ; chart of electrical dimensions of, 77. Effect of continued action on voltaic cell, 13. Efficiency, working, of lines, importance of high, 135 ; best method of improving, 135 ; examples of advantageous results of, 135, 136; of telegraphic circuit, in ; computation of, 128. ruo, 34. Electricity, theories of nature of, 2 ; origin of, 3 ; sources of, 3 ; characteristics of capable of measurement, 43; apparatus required for measurement of, 43 ; provisional theory of, 58 ; production ot in battery in proportion to material consumed, 76. Electrolysis of liquids by electric current, 36. Electro-magnet, the, 80 ; its modern form invented by Henry, 80 ; polarity of determined by direction of current, 81 ; elements of, 81 ; adaptation of to working currents, 96 ; spectrum of, 96, 97 ; indirect causes of retardation in, 99 ; with polarized armature, xop ; differential, principle of, 171 ; construction of, 172. Erg, unit of work, definition of, 38. Escape or leakage on line, 190 ; testing for, 192; <n line, locating position of, 202; ditto by double measurement, 203 ; by loop test, 203. Farad .y. Michael, biographical notice of, 73. Faraday s theory of electricity, 2 ; discovery of magneto-electricity, 29 ; Experimental Researches^ references to, 3, 29 ; lines of magnetic force, 27, 28. Farmer, M. G., on resistances or' battery solutions, 62 ; observations on earth circuit as affected by character of soil, 107 ; on effects of wet upon telegraphic insulation, 119 ; on working efficiency of telegraph lines, 128; table of percentages of received current on telegraph lines, 136. plained, 38. Force, definition of, 27 ; lines of, a measure of magnetic field, 82 ; relation of current to mechanical, 40 ; unit of, defined, 37. and resistances of, 112. Galvanometer, the, 41 ; how shown in diagram, 104 ; astatic, 200 : differential, construction of, 208 ; for Wneatstone bridge, 198. Galvanometer, tangent, 41, 209; construction of, 41 ; use of in testing insulation by received currents, 209 ; in experimental investigations, 52 ; table of tangents for, and Magnetism, reference to, 40. Ground or earth plate, how shown in diagram, 104 ; at distant station, measuring resistance of, 202 ; defective, effect ot, 191. copper cell, 74. Helices of electro-magnets, machine for winding, 93 ; thickness of spaces between wires of, 94 ; of bare copper wire, 94. Helix, magnetic, effect of iron in, 84; effect of position of windings in, 92 ; construction of, 92 ; relation of number of turns to thickness and length of wire in, 92 ; number of turns in, measured by its resistance, 93. tests of, 133, 134. Insulation, imperfect, effects of, no ; defective of American lines, 118 ; effects of climate upon, 118 ; effect of upon flow of current, 127 ; Farmer's table of, 136. Insulator, glass, Western Union, old pattern, 116 ; new standard pattern, i r6 ; hard rubber, 117; paraffin, 117 ; porcelain, 118. Insulators, telegraphic line, 115; common glass, 115 ; defects of, 115; resistance of influenced by form, 116; comparison of different forms ot, 116; tests of, 120, 134; measurement of resistance of, 206 ; value of wu poles and cross-arms considered as, 133. Kerite insulation for office wires, 113, 114. Key, construction of, 138 ; adjustment of, 140 ; platinum contacts of, 138 ; modifications of, 139 ; Western Electric pattern, 140; Victor pattern, 140; double-current or reversing, 180 ; common Morse, how shown in diagram, 104 ; three-point, how shown in diagram, 104 ; method of handling, 219 ; preliminary practice with, 220. j Lightning arrester, description of, 160; combination of with switch, 156, 157; inspection and care of, 161 ; how shown in diagram, 104. j Line, computation of working efficiency of, 128 ; electrostatic capacity of, 175 ; overhead, diagram of, 104 ; submarine or subterranean, diagram of, 104 ; artificial, of multiple telegraph, 174. \| Lines, leaky, resistance and current in, 128 ; table for computing resistances and escapes upon various lengths of, 129 ; best position for battery on, 131, 132 ; effect of pos.tion of fault in, 131. remanent or residual, 98. rnetism, definition ol, 24 ; characteristics f, 24 ; unit of, 83 ; intensity of, 83 ; density f , 83 ; lines of force a measure of, 82 ; of, 2. Magnetization, of one body by another, 25; intensity of defined, 86 ; proportional to ampere-turns, 87 ; maximum limit of in soli iron, 87. Measurement, absolute system of, 37; quantitative electrical, theory of, 35 ; importance of, 36; electrical, character of, 43 ; practice of, 195. North British Review, extract from, 56. Nystrom, J. W., definition of force. 27. Nystrom's Elements of Mechanics, extract Potential, conception of. 59 ; of telegraph line, determination of by calculation, 123 ; of line, measurement of by auxiliary battery, 122. Potential, electric, explanation of, 69 ; fall of along conductor, illustration of, 70 ; proportionate to resistance, 71 ; in perfectly insulated circuit, distribution of, 120 ; in imperfectly insulated circuit, 125; within battery, 123. Proportional deflections, measuring high resistances by method of, 205, 206 ; measuring resistance of insulators by, 206. 182 ; a combination of diplex and contraplex systems, 184; distribution of currents in, 186 ; how worked by dynamo currents, 185; practical management of, 187; adjustment of apparatus of, 188 ; repeaters for, 189. RAIN WATER, should be used in batteries, 5. Rate, of consumption of material in voltaic cell. 13; of work of electric current, how found, 64 ; relation of to time, 73. Reduced length of conductor, meaning of, 58. Register, the, 147 ; construction of, 147 ; European pattern of, 148 ; combination of with key and relay, 149 ; adjustments of, 149 ; causes of defective marking in, 150 ; ink-writing, 150 ; how shown in diagram, 104. Relay, construction of, 144 : function of, 146 ; adjustments of, 147 ; short core, for diplex and quadruplex apparatus, 184 ; polar, or polarized, 180 ; how shown in diagram, 104 ; common or non-polarized, how shown in diagram, 104. Repeater, the, 162 ; manual and automatic, 162- button, 162; Wood's, 164: Milliken s, 165; for duplex, quadruplex, and multiple systems, 189. Residual or remanent magnetism, 98. Resistance, electrical, explanation of, 56; conditions affecting, 58 • expressible in terms of length, 58 ; artificial, how shown in diagram, 104. Resistance, of circuit, relation of to quantity of current flowing in, 56 ; abnormal on line, method of locating, 205 ; relation of conductivity to insulation of line, no; ratio of conductivity to insulation, minimum, 128. ment of with bridge, 199. Resistance, insulation, of line, measurement of, 202 ; of insulators, method of measuring, 206 ; of various kinds of insulators, 1 20. to determine. 66. Resistance, specific, of different metals, 57 ; of copper wires for electro-magnets, table ot, 94 ; of galvanized iron, hard-drawn and soft copper wires, Prescott's table of, 112 ; of metals emploved as conductors in telegraphv, percentage of increase in by rise of temperature, 78. Resistance of liquids, Farmer's values of, 62; Becker's ditto, 63 ; of sulphate of copper solution, 62, 63 ; of sulphate of zinc solution, 62, 63 ; internal, of voltaic cell, 64 ; of ordinary gravity cell, 74 ; of sulphate of copper cell, effect of temperature upon, 78 : experiments of Preece on, 78 ; internal, of battery, methods of measuring, 207. Resistance, very high, methods of measuring, 205 ; of galvanometers, method of measuring, 208; of helix, a measure of number of turns in, 93; of leaky Hues, in, 223. Sounder, the, 141 ; adaptation of to short lines, 142 ; adjustment of, 142; combination kev and, 143 ; pocket. 144 ; box, 144 ; how shown in diagram, 104. Swinging cross, 191. Switch, universal, how shown in diagram, 104; three-point, how shown in diagram, 104; pole-changing, how shown in diagram, TANGENT GALVANOMETER, description of, 41 ; principle of, 42 ; details of construction of, 45; Western Union pattern, 209; use of in testing insulation by received currents, 209. Telegraphic magnet, theoretical proportions of, 91 ; details of construction of, 91 ; spectrum of, 97 : effects of self-induction an<l hysteresis in, 99. Temperature, effect of, on action of voltaic cell, 20, 78 ; on resistance of substances, 58 ; effect of in increasing resistance of metals employed as telegraphic conductors, 78. Thompson's Elementary Lessons in Electricity and Magnetism, reference to, 31, 198 ; Dynamo-Electric Machinery, reference to, 86. Thomson, Sir William, on importance of quantitative measurement in physical science, 36; Popular Lectures and Addresses, extract from. 36. Units, lundamental and derived, 37 ; electrical, synoptical table of, 73 ; practical, derived from natural constants, 59. reports of, 40. VAIL, ALFRED, biographical notice of, 216 ; originator of the telegraphic register in its present form, 216 ; of the alphabetical code, 216. Voltameter, the, 44. Voltmeter, use of in telegraphic testing. 210 ; Weston's portable, 210- advantages of for testing, 211 : Weston's combined ammeter and, for telegraphic testing, 210, 211. TABLE, 112. Watt, James, biographical notice of, 73. Watt, the unit of power or rate of work, value of, 73 ; rule for determination of, Way-station, arrangement of apparatus at, 151 ; connections ot, 152 ; manipulation of switchboard in, 153 ; testing in, 154. Elements of Electric Lighting, including Electric Generation, Measurement, Storage, and Distribution. Eighth Edition. Fully revised and new matter added. Illustrated. 8vo, cloth. $1.50. Bell Hanger's Handbook. Third Edition. Illustrated. 12mo, cloth. $1.00. BIGGS, C. 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Svo, cloth. $2.50. Electric Ship-Lighting. A Hand-book on the Practical Fitting and Running of Ships' Electrical Plant, for the Use of Ship Owners and Builders, Marine Electricians and Sea-going Engineers in Charge. 88 Illustrations. 12mo, cloth. $3.00. Electric Light Fitting. A Hand-book for Working Electrical Engineers, Embodying Practical Notes on Installation Management. Second Edition, with additional chapters. With numerous Illustrations. 12mo, cloth. $2.00. WORMELL, R. Electricity in the Service of Man. A Popular and Practical Treatise on the Application of Electricity in Modern Life. From the German, and edited, with copious additions, by R. Wormell, and an Introduction by Prof. J. Perry. WTith nearly 850 Illustrations. Royal 8vo, cloth. $5.00. WEYMOUTH, F. MARTEN. Drum Armatures and Commutators. (Theory and Practice.) A complete treatise on the theory and construction of drumwinding, and of commutators for closed-coil armatures, together with a full resumt of some of the principal points involved in their design ; and an exposition of armature reactions and sparking. Illustrated. 8vo, cloth. $3.00.	91,601	common-pile/pre_1929_books_filtered	modernpracticeof00poperich	public_library	public_library_1929_dolma-0002.json.gz:4432	https://archive.org/download/modernpracticeof00poperich/modernpracticeof00poperich_djvu.txt
9LIVEnHQh_Wc5prU	Criminal Justice	1 Request Access This text is openly licensed and is accessible to all by navigating using the “Contents” menu in the upper left hand corner. To preserve academic integrity and prevent students from gaining unauthorized access, we have hidden faculty resources and assessments. Please contact<EMAIL_ADDRESS>to request access to the faculty resources for this course. Once you have been given access, you’ll be able to use the resources provided through the drop down in the upper left hand corner. Overview of Faculty Resources This is a community course developed by an Achieving the Dream grantee. They have either curated or created a collection of faculty resources for this course. Since the resources are openly licensed, you may use them as is or adapt them to your needs. Now Available - Question Banks - Assessments Share Your Favorite Resources If you have sample resources you would like to share with other faculty teaching this course, please send them with an explanatory message and learning outcome alignment to oer@achievingthedream.org.	215	common-pile/pressbooks_filtered	https://library.achievingthedream.org/bmcccriminaljustice/chapter/request-access/	pressbooks	pressbooks-0000.json.gz:76947	https://library.achievingthedream.org/bmcccriminaljustice/chapter/request-access/
A_UwabkAbsYnaA9N	Corporate Finance	9.16 Economic Ordering Quantity (EOQ) Model Inventory Optimal Order Quantities Model Objective: Optimize inventory level. The company may experience a saw-tooth pattern of inventory levels. (Other assumptions shall also remain as they were in the cash model example). As (average) inventory and order quantity increases so do: - Financing costs: inventory needs to be paid from either short-term borrowings or the opportunity cost of cash invested in the short-term. (We shall, disingenuously, assume that borrowing and lending rates are the same.) - Other carrying costs: - Storage & handling - Labor, electricity, etc. - Insurance - Perishability / (Demurrage “on the docks”) - Obsolescence - To summarize: “Carrying” costs rise with inventory size As inventory increases, the following decreases: - Ordering costs – administrative - Price/cost due to quantity discounts - Cost of stock-out, i.e., not being able to fulfill customer orders - “Ordering” costs decrease with inventory size \| Total Cost = Carrying + Ordering Costs \| \| \| Carrying Costs = (Q / 2) (P) (C) \| Q / 2 = Average inventory Carried P = Price paid per unit C = All carrying costs including financing costs (expressed as percent of cost) \| \| Ordering Costs = (F) (S / Q) \| F = Fixed cost per order S = Annual unit sales projected Q = Periodic ordering quantity (units) \| \| (Q / 2) (P) (C) = (F) (S / Q) (Q / S) (Q / 2) = F / PC) Q2 = (2 F S) / (P C) Q* = [(2 F S) ÷ (C P)] 0.5 \|	341	common-pile/pressbooks_filtered	https://touro.pressbooks.pub/corporatefinance/chapter/9-16-economic-ordering-quantity-eoq-model-inventory-optimal-order-quantities-model-2/	pressbooks	pressbooks-0000.json.gz:29201	https://touro.pressbooks.pub/corporatefinance/chapter/9-16-economic-ordering-quantity-eoq-model-inventory-optimal-order-quantities-model-2/
OQnlHAbbwmqKRqMA	1: Part I: Underlying Ethical Issues and Value of Technologies: Artificial Intelligence, Social Networking Services, 3D Printing	1: Part I: Underlying Ethical Issues and Value of Technologies: Artificial Intelligence, Social Networking Services, 3D Printing Last updated Save as PDF Page ID 85533 Barbara Brown, Verena Roberts, Michele Jacobsen, Christie Hurrell, Kourtney Kerr, Heather van Streun, Nicole Neutzling, Jeff Lowry, Simo Zarkovic, Jennifer Ansorger, Terri Marles, Emma Lockyer, and Dean Parthenis University of Calgary via Open Education Alberta 1.1: Chapter 1: Ethical Considerations When Using Artificial Intelligence-Based Assistive Technologies in Education 1.2: Chapter 2: Beware: Be Aware - The Ethical Implications of Teachers Who Use Social Networking Sites (SNSs) to Communicate 1.3: Chapter 3: From Consumers to Prosumers: How 3D Printing is Putting Us in the Driver’s Seat for Creation and the Ethical Considerations that Accompany this Shift.	156	common-pile/libretexts_filtered	https://socialsci.libretexts.org/Bookshelves/Education_and_Professional_Development/Ethical_Use_of_Technology_in_Digital_Learning_Environments_-_Graduate_Student_Perspectives/01%3A_Part_I%3A_Underlying_Ethical_Issues_and_Value_of_Technologies%3A_Artificial_Intelligence_Social_Networking_Services_3D_Printing	libretexts	libretexts-0000.json.gz:22811	https://socialsci.libretexts.org/Bookshelves/Education_and_Professional_Development/Ethical_Use_of_Technology_in_Digital_Learning_Environments_-_Graduate_Student_Perspectives/01%3A_Part_I%3A_Underlying_Ethical_Issues_and_Value_of_Technologies%3A_Artificial_Intelligence_Social_Networking_Services_3D_Printing
bH8VtWALbXIwxA1x	RANGE: Journal of Undergraduate Research (2024)	College of Nursing 61 The Essential Role of Effective Naloxone Distribution in Overdose Prevention Mia Sheneman; Jacob Steenblik; Nehal Bakshi; Kate Flynn; and Marina Griffith Faculty Mentor: Jacob Steenblik (Nursing, University of Utah) Opiate overdose is a widespread issue in the United States which has particularly affected Utah. Naloxone, also known as Narcan, is an opioid overdose reversal drug which can effectively stop a lethal overdose by competitively inhibiting opiates from binding to their receptors. Since opioid overdose is a concern within the Salt Lake City community, it is vital that overdose education and naloxone distribution (OEND) is available, so people are aware of this rescue drug and how to use it, especially if they often encounter people who are at a higher risk of opioid use or abuse. The purpose of this ongoing quantitative research study is to understand common perceptions of opioid reversal drugs and the need of OEND within the population presenting to the University of Utah Emergency Department (UUED). Survey responses were collected from patients of the UUED using convenience sampling, with a follow-up survey conducted 30 days later via phone call. Results of our study thus far have suggested that the UUED may benefit from implementing a naloxone distribution program. For example, 23.0% (n=1,267) of respondents stated that they currently have a close friend or family member who uses opioids. Furthermore, 29.6% (n=1,266) of respondents have had a family member or close friend die of a drug overdose. These findings highlight the potential effectiveness of encouraging naloxone carrying among individuals in these communities to help prevent overdose-related deaths. To demonstrate the need for effective distribution programs, 63.3% (n=1,266) stated that they would be interested in receiving a free naloxone kit from the emergency department, yet 30 days later only 5.4% (n=866) of respondents had picked up free naloxone from the provided resources. This difference shows the importance of effective distribution strategies. Although Utah’s public libraries pass out naloxone for free, people may feel more comfortable obtaining it in a setting that they already disclose health information such as the emergency department. The UUED is also more likely to encounter people who are at risk of opioid overdose, making it an excellent place for distribution. In conclusion, this study highlights the need for effective distribution strategies within opioid overdose education and naloxone distribution (OEND) programs. From our follow-up phone calls, 20 out of 862 respondents indicated they had been in a situation where naloxone could have been helpful within the past 30 days. Although this may seem insignificant, each instance represents a scenario where naloxone access could have made a difference. These findings emphasize the University of Utah Emergency Department’s unique opportunity to positively impact lives in Salt Lake City and surrounding communities by enhancing its overdose education and naloxone distribution efforts.	605	common-pile/pressbooks_filtered	https://uen.pressbooks.pub/range25i2/chapter/sheneman/	pressbooks	pressbooks-0000.json.gz:55267	https://uen.pressbooks.pub/range25i2/chapter/sheneman/
0fox4Oy9KgpWHULa	2.3: Chemical bonds	2.3: Chemical bonds Atoms form bonds to make molecules. Covalent bonds are strong. They can involve unequal or equal sharing of a pair of electrons, leading to polar covalent bonds and non-polar covalent bonds respectively. Ionic bonds are weaker than covalent bonds, created by electrostatic interactions between elements that can gain or lose electrons. Hydrogen (H-) bonds are in a class by themselves! These electrostatic interactions account for the physical and chemical properties of water. They are also involved in interactions between and within other molecules. While atoms can share, gain or lose electrons in chemical reactions, they will neither gain nor lose protons or neutrons. Let’s look more closely at chemical bonds and how even the weak bonds are essential to life. A. Covalent Bonds Electrons are shared in covalent bonds. Hydrogen gas (H2) is a molecule, not an atom! H atoms in the H2 molecule share their electrons equally. Likewise, the carbon atom in methane (CH4) shares electrons equally with four hydrogen atoms. The equal sharing of electrons in non-polar covalent bonds in H2 and CH4 is shown below. A single pair of electrons in H2 forms the covalent bond between two H atoms in the hydrogen molecule. In methane, the carbon (C) atom has four electrons in its outer shell that it can share. Each H atom has a single electron to share. If the C atom shares its four electrons with the four electrons in the four H atoms, there will be four paired electrons (8 electrons in all) moving in filled orbitals around the nucleus of the C atom some of the time, and one pair moving around each of the H atomic nuclei some of the time. Thus, the outer shell of the C atom and each of the H atoms are filled at least some of the time. This stabilizes the molecule. Recall that atoms are most stable when their outer shells are filled and when each electron orbital is filled (i.e., with a pair of electrons). Polar covalent bonds form when electrons in a molecule are shared unequally. This happens if the atomic nuclei in a molecule are very different in size. This is the case with water, shown below. The larger nucleus of the oxygen atom in H2O attracts electrons more strongly than do either of the two H atoms. As a result, the shared electrons spend more of their time orbiting the O atom, such that the O atom carries a partial negative charge while each of the H atoms carry a partial positive charge . The Greek letter delta ( d ) indicates partial charges in polar covalent bonds. In the two illustrations above, compare the position of the paired electrons in water with those illustrated for hydrogen gas or methane. Water’s polar covalent bonds allow it to attract and interact with other polar covalent molecules, including other water molecules. The polar covalent nature of water also goes a long way to explaining its physical and chemical properties, and why water is essential to life on this planet! Both polar and non-polar covalent bonds play a major role on the structure of macromolecules, like insulin , the protein hormone shown below. The X-ray image of a space-filling model of the hexameric form of stored insulin (above left) emphasizes its tertiary structure in great detail. Regions of internal secondary structure are highlighted in the ribbon diagram on the right; as secreted from Islets of Langerhans cells of the pancreas , active insulin is a dimer of two polypeptides (A and B), shown here in blue and cyan respectively. The subunit structure and the interactions holding the subunits together result from many electrostatic interactions (including H-bonds) and other weak interactions. The disulfide bonds (bridges) seen as yellow ‘Vs’ in the ribbon diagram stabilize the associated A and B monomers. We will look at protein structure in more detail in an upcoming chapter. B. Ionic Bonds Atoms that gain or lose electrons to achieve a filled outer shell form ions , acquiring a negative or a positive charge, respectively. Despite being electrically charged, ions are stable because their outer electron shells are filled. Common table salt is a good example (illustrated below). Na (sodium) can donate a single electron to Cl (chlorine) atoms, generating Na+ and Cl- ions. The oppositely charged ions then come together forming an ionic bond , an electrostatic interaction of opposite charges that holds the Na+ and Cl- ions together in crystal salt. Look up the Bohr models of these two elements and see how ionization of each leaves filled outer shells (energy levels) in the ions.	999	common-pile/libretexts_filtered	https://bio.libretexts.org/Bookshelves/Cell_and_Molecular_Biology/Book%3A_Basic_Cell_and_Molecular_Biology_(Bergtrom)/02%3A_Basic_Chemistry_Organic_Chemistry_and_Biochemistry/2.03%3A_Chemical_bonds	libretexts	libretexts-0000.json.gz:33063	https://bio.libretexts.org/Bookshelves/Cell_and_Molecular_Biology/Book%3A_Basic_Cell_and_Molecular_Biology_(Bergtrom)/02%3A_Basic_Chemistry_Organic_Chemistry_and_Biochemistry/2.03%3A_Chemical_bonds
DP7xts3MXKGV4-V6	Basic Motor Control	Circuits 29 Sump-Pump Circuit A three-position selector switch may be used to provide either manual or automatic control. When the switch is moved to the HAND position, the magnetic starter is energized. This is useful for testing the condition of the motor and verifying the direction of rotation. When the selector switch is moved to the AUTO position, the magnetic starter is controlled by the opening or closing of the float-switch contacts. The diagram below shows a sump-pump circuit, while the figure represents the tank that it empties. If the water level is low, both float switches are normally open and the motor does not run. If the water level rises, FS 2 will close first, but the motor will not start. Current cannot get past FS 1 nor the normally open auxiliary contacts. If the water level rises to fill the tank and FS 1 closes, the motor will energize and start pumping water out of the tank and very quickly FS 1 will open again. This is where having two pilot devices allows us a greater range in sensitivity. Even though FS 1 opens almost immediately, the auxiliary contact keeps the motor running until the tank is fully emptied and FS 2 opens. With only a single pilot device the motor would only drain a small portion of the tank and would be subjected to multiple starts and stops. Using two pilot devices to control the motor allows for more efficient operation of the motor. This circuit shows the arrangement for a tank-drain function. A simple rearrangement of contacts can provide a tank-fill function as well. A device for making or breaking the connection in an electric circuit. A contact that under normal conditions does not have continuity through it. When the contact changes its state it permits the flow of current by closing its contacts. Can be associated with pushbuttons, pilot devices or magnetic contactors. Contacts on a magnetic starter that are not Horsepower rated. Can come as either normally-open or normally-closed and can be used as maintaining contacts, electrical interlocks or control for pilot lights. An auxilary device that provides indication or control of a process to an operator. Pilot devices include automatic switches such as float and pressure switches, as well as indicating lights. The conducting part of a switch that makes or breaks a circuit.	508	common-pile/pressbooks_filtered	https://opentextbc.ca/basicmotorcontrol/chapter/sump-pump-circuit/	pressbooks	pressbooks-0000.json.gz:12356	https://opentextbc.ca/basicmotorcontrol/chapter/sump-pump-circuit/
7No5qCTsBK5AJTca	4.4: Children’s Understanding of the World	4.4: Children’s Understanding of the World - - Last updated - Save as PDF Both Piaget and Vygotsky believed that children actively try to understand the world around them. More recently developmentalists have added to this understanding by examining how children organize information and develop their own theories about the world. Theory-Theory The tendency of children to generate theories to explain everything they encounter is called theory-theory . This concept implies that humans are naturally inclined to find reasons and generate explanations for why things occur. Children frequently ask question about what they see or hear around them. When the answers provided do not satisfy their curiosity or are too complicated for them to understand, they generate their own theories. In much the same way that scientists construct and revise their theories, children do the same with their intuitions about the world as they encounter new experiences (Gopnik & Wellman, 2012). One of the theories they start to generate in early childhood centers on the mental states; both their own and those of others. Theory of Mind Theory of mind refers to the ability to think about other people’s thoughts. This mental mind reading helps humans to understand and predict the reactions of others, thus playing a crucial role in social development. One common method for determining if a child has reached this mental milestone is the false belief task, described below. The research began with a clever experiment by Wimmer and Perner (1983), who tested whether children can pass a false-belief test (see Figure 4.17). The child is shown a picture story of Sally, who puts her ball in a basket and leaves the room. While Sally is out of the room, Anne comes along and takes the ball from the basket and puts it inside a box. The child is then asked where Sally thinks the ball is located when she comes back to the room. Is she going to look first in the box or in the basket? The right answer is that she will look in the basket, because that’s where she put it and thinks it is; but we have to infer this false belief against our own better knowledge that the ball is in the box. This is very difficult for children before the age of four because of the cognitive effort it takes. Three-year-olds have difficulty distinguishing between what they once thought was true and what they now know to be true. They feel confident that what they know now is what they have always known (Birch & Bloom, 2003). Even adults need to think through this task (Epley, Morewedge, & Keysar, 2004). To be successful at solving this type of task the child must separate what he or she “knows” to be true from what someone else might “think” is true. In Piagetian terms, they must give up a tendency toward egocentrism. The child must also understand that what guides people’s actions and responses are what they “believe” rather than what is reality. In other words, people can mistakenly believe things that are false and will act based on this false knowledge. Consequently, prior to age four children are rarely successful at solving such a task (Wellman, Cross & Watson, 2001). Researchers examining the development of theory of mind have been concerned by the overemphasis on the mastery of false belief as the primary measure of whether a child has attained theory of mind. Wellman and his colleagues (Wellman, Fang, Liu, Zhu & Liu, 2006) suggest that theory of mind is comprised of a number of components, each with its own developmental timeline (see Table 4.2). Two-year-olds understand the diversity of desires, yet as noted earlier it is not until age four or five that children grasp false belief, and often not until middle childhood do they understand that people may hide how they really feel. In part, because children in early childhood have difficulty hiding how they really feel. Cultural Differences in Theory of Mind Those in early childhood in the US, Australia, and Germany develop theory of mind in the sequence outlined above. Yet, Chinese and Iranian preschoolers acquire knowledge access before diverse beliefs (Shahaeian, Peterson, Slaughter & Wellman, 2011). Shahaeian and colleagues suggested that cultural differences in childrearing may account for this reversal. Parents in collectivistic cultures, such as China and Iran, emphasize conformity to the family and cultural values, greater respect for elders, and the acquisition of knowledge and academic skills more than they do autonomy and social skills (Frank, Plunkett & Otten, 2010). This could reduce the degree of familial conflict of opinions expressed in the family. In contrast, individualistic cultures encourage children to think for themselves and assert their own opinion, and this could increase the risk of conflict in beliefs being expressed by family members. As a result, children in individualistic cultures would acquire insight into the question of diversity of belief earlier, while children in collectivistic cultures would acquire knowledge access earlier in the sequence. The role of conflict in aiding the development of theory of mind may account for the earlier age of onset of an understanding of false belief in children with siblings, especially older siblings (McAlister & Petersen, 2007; Perner, Ruffman & Leekman, 1994). This awareness of the existence of theory of mind is part of social intelligence, such as recognizing that others can think differently about situations. It helps us to be self-conscious or aware that others can think of us in different ways and it helps us to be able to be understanding or be empathetic toward others. Moreover, this mind-reading ability helps us to anticipate and predict people’s actions. The awareness of the mental states of others is important for communication and social skills. 21 Contributors and Attributions 21. Lifespan Development: A Psychological Perspective by Martha Lally and Suzanne Valentine-French is licensed under CC BY-NC-SA 3.0	1,271	common-pile/libretexts_filtered	https://socialsci.libretexts.org/Courses/Moraine_Park_Technical_College/Child_Growth_and_Develpment_(MPTC_Version)/04%3A_Cognitive_Development_in_Early_Childhood/4.04%3A_Childrens_Understanding_of_the_World	libretexts	libretexts-0000.json.gz:17552	https://socialsci.libretexts.org/Courses/Moraine_Park_Technical_College/Child_Growth_and_Develpment_(MPTC_Version)/04%3A_Cognitive_Development_in_Early_Childhood/4.04%3A_Childrens_Understanding_of_the_World
FfEpWTn_nBqsTzgb	Emergence of a Strategic Leader	What Is the Environment? For any organization, the environment consists of the set of external conditions and forces that have the potential to influence the organization. In the case of Subway, for example, the environment contains its customers, its rivals such as McDonald’s and Kentucky Fried Chicken, social trends such as the shift in society toward healthier eating, political entities such as the US Congress, and many additional conditions and forces. It is useful to break the concept of the environment down into two components. The general environment (or macroenvironment) includes overall trends and events in society such as social trends, technological trends, demographics, and economic conditions. The industry (or competitive environment) consists of multiple organizations that collectively compete with one another by providing similar goods, services, or both. Every action that an organization takes, such as raising its prices or launching an advertising campaign, creates some degree of changes in the world around it. Most organizations are limited to influencing their industry. Subway’s move to cut salt in its sandwiches, for example, may lead other fast-food firms to revisit the amount of salt contained in their products. A few organizations wield such power and influence that they can shape some elements of the general environment. While most organizations simply react to major technological trends, for example, the actions of firms such as Intel, Microsoft, and Apple help create these trends. Some aspects of the general environment, such as demographics, simply must be taken as a given by all organizations. Overall, the environment has a far greater influence on most organizations than most organizations have on the environment. Why Does the Environment Matter? Understanding the environment that surrounds an organization is important to the executives in charge of the organizations. There are several reasons for this. First, the environment provides resources that an organization needs in order to create goods and services. In the seventeenth century, British poet John Donne famously noted that “no man is an island.” Similarly, it is accurate to say that no organization is self-sufficient. As the human body must consume oxygen, food, and water, an organization needs to take in resources such as labor, money, and raw materials from outside its boundaries. Subway, for example, simply would cease to exist without the contributions of the franchisees that operate its stores, the suppliers that provide food and other necessary inputs, and the customers who provide Subway with money through purchasing its products. An organization cannot survive without the support of its environment. Second, the environment is a source of opportunities and threats for an organization. Opportunities are events and trends that create chances to improve an organization’s performance level. In the late 1990s, for example, Jared Fogle’s growing fame created an opportunity for Subway to position itself as a healthy alternative to traditional fast-food restaurants. Threats are events and trends that may undermine an organization’s performance. Subway faces a threat from some upstart restaurant chains. Saladworks, for example, offers a variety of salads that contain fewer than five hundred calories. Noodles and Company offers a variety of sandwiches, pasta dishes, and salads that contain fewer than four hundred calories. These two firms are much smaller than Subway, but they could grow to become substantial threats to Subway’s positioning as a healthy eatery. Executives must also realize that virtually any environmental trend or event is likely to create opportunities for some organizations and threats for others. This is true even in extreme cases. In addition to horrible human death and suffering, the March 2011 earthquake and tsunami in Japan devastated many organizations, ranging from small businesses to corporate giants such as Toyota, whose manufacturing capabilities were undermined. As odd as it may seem, however, these tragic events also opened up significant opportunities for other organizations. The rebuilding of infrastructure and dwellings requires concrete, steel, and other materials. Japanese concrete manufacturers, steelmakers, and construction companies are likely to be very busy in the years ahead. Third, the environment shapes the various strategic decisions that executives make as they attempt to lead their organizations to success. The environment often places important constraints on an organization’s goals, for example. A firm that sets a goal of increasing annual sales by 50 percent might struggle to achieve this goal during an economic recession or if several new competitors enter its business. Environmental conditions also need to be taken into account when examining whether to start doing business in a new country, whether to acquire another company, and whether to launch an innovative product, to name just a few. The Elements of the General Environment: PESTEL Analysis An organization’s environment includes factors that it can readily affect as well as factors that largely lay beyond its influence. The latter set of factors are said to exist within the general environment. Because the general environment often has a substantial influence on an organization’s level of success, executives must track trends and events as they evolve and try to anticipate the implications of these trends and events. PESTEL analysis is one important tool that executives can rely on to organize factors within the general environment and to identify how these factors influence industries and the firms within them. PESTEL is an anagram, meaning it is a word that created by using parts of other words. In particular, PESTEL reflects the names of the six segments of the general environment: (1) political, (2) economic, (3) social, (4) technological, (5) environmental, and (6) legal. Wise executives carefully examine each of these six segments to identify major opportunities and threats and then adjust their firms’ strategies accordingly. \| P \| Political factors include elements such as tax policies, changes in trade restrictions and tariffs, and the stability of governments. \| \| E \| Economic factors include elements such as interest rates, inflation rates, gross domestic product, unemployment rates, levels of disposable income, and the general growth or decline of the economy. \| \| S \| Social factors include trends in demographics such as population size, age, and ethnic mix, as well as cultural trends such as attitudes toward obesity and consumer activism. \| \| T \| Technological factors include, for example, changes in the rate of new product development, increases in automation, and advancements in service industry delivery. \| \| E \| Environmental factors include, for example, natural disasters and weather patterns. \| \| L \| Legal factors include laws involving issues such as employment, health and safety, discrimination, and antitrust. \| Table 1 PESTEL Examining the general enviornment involves gaining an understanding of key factors and trends in broader society. PESTEL analysis is a popular framework for organizing these factors and trends and isolating how they influence industries and the firms within them. Below we describe each of the six dimensions associated with PESTEL analysis: political, economic, social, technological, environmental, and legal. P Is for “Political” The political segment centers on the role of governments in shaping business. This segment includes elements such as tax policies, changes in trade restrictions and tariffs, and the stability of governments (Table 2 “Political Factors”). Immigration policy is an aspect of the political segment of the general environment that offers important implications for many different organizations. What approach to take to illegal immigration into the United States from Mexico has been a hotly debated dilemma. Some hospital executives have noted that illegal immigrants put a strain on the health care system because immigrants seldom can pay for medical services and hospitals cannot by law turn them away from emergency rooms. \| The extent to which companies developing clean energy sources should be subsidized by the government versus being left on their own to compete with providers of traditional energy sources is currently a hotly contested political issue. \| \| The use of child labor was once commonplace in the United States now firms face political scrutiny when using overseas suppliers that employ child labor. \| \| The word tariff derived from an Arabic word meaning “fees to be paid.” By levying tariffs and implementing other trade restrictions, governments can — to some extent — protect domestic firms from international competition. \| \| The stability of the US government provides a source of confidence for foreign firms who want to do business in the United States. Countries that face frequent regime change and political turmoil have a harder time attracting foreign investments. \| \| One of the most important duties of elected officials in the United States is to debate and set new tax policies. \| Table 2 Political Factors Examples of several key trends representing political factors in the general environment are illustrated above. Proposals to provide support to businesses are often featured within political campaigns. Meanwhile, farmers argue that a tightening of immigration policy would be harmful because farmers rely heavily on cheap labor provided by illegal immigrants. In particular, if farmers were forced to employ only legal workers, this would substantially increase the cost of vegetables. Restaurant chains such as Subway would then pay higher prices for lettuce, tomatoes, and other perishables. Subway would then have to decide whether to absorb these costs or pass them along to customers by charging more for subs. Overall, any changes in immigration policy will have implications for hospitals, farmers, restaurants, and many other organizations. E Is for “Economic” The economic segment centers on the economic conditions within which organizations operate. It includes elements such as interest rates, inflation rates, gross domestic product, unemployment rates, levels of disposable income, and the general growth or decline of the economy. The economic crisis of the late 2000s has had a tremendous negative effect on a vast array of organizations. Rising unemployment discouraged consumers from purchasing expensive, nonessential goods such as automobiles and television sets. Bank failures during the economic crisis led to a dramatic tightening of credit markets. This dealt a huge blow to home builders, for example, who saw demand for new houses plummet because mortgages were extremely difficult to obtain. \| Housing starts in an economic indicator that measures the number of houses, apartments, and condos on which new construction has been started. Because construction involves a wide array of industries–concrete, steel, wood, drywall, plumbing, banks, and many others–housing starts are a carefully watched measure of economic conditions. \| \| Gross domestic product (GDP) refers to the market value of goods and services within a country produced in a given time period and serves as a rough indicator of a country’s standard of living. The United States has a much larger GDP than China, but China has enjoyed a much higher rate of GDP growth in recent years. \| \| The Federal Reserve System (commonly referred to as “The Fed”) is the United States’ central banking system. The Fed attempts to strengthen the economy through its decisions, such as setting short-term interest rates. \| \| Discretionary income refers to the amount of money individuals have to spend after all necessary bills are paid. As discretionary income increases, firms such as boutique clothing retailers that sell nonessential goods and services are more likely to prosper. \| Table 3 Economic Factors. Examples of several key trends representing economic factors in the general environment are illustrated below. The unemployment rate is the percentage of the labor force actively lookin for employment within the last four weeks. During the Great Depression of the 1930s, the United States suffered through an unemployment rate of approximately 25%. Some businesses, however, actually prospered during the crisis. Retailers that offer deep discounts, such as Dollar General and Walmart, enjoyed an increase in their customer base as consumers sought to find ways to economize. Decisions about interest rates made by the Federal Reserve create opportunities for some organizations and threats for others. S Is for “Social” A generation ago, ketchup was an essential element of every American pantry and salsa was a relatively unknown product. Today, however, food manufacturers sell more salsa than ketchup in the United States. This change reflects the social segment of the general environment. Social factors include trends in demographics such as population size, age, and ethnic mix, as well as cultural trends such as attitudes toward obesity and consumer activism. The exploding popularity of salsa reflects the increasing number of Latinos in the United States over time, as well as the growing acceptance of Latino food by other ethnic groups. \| The rise of upscale cupcake outlets reflects a current trend in American eateries: pricey specialty stores are very popular among some consumers. \| \| Hunters remain a powerful force in American society, but their ranks shrunk by 10% between 1996 and 2006. Wildlife agencies worry about the loss of license-fee revenue will affect their ability to manage land and water resources, and lower levels of demand for their products threaten the success of gun makers. \| \| In the 1800s, most American couples raised many children. Farmers, for example, took this approach because it supplied labor that small farms needed in order to operate. Today, most families are smaller. \| \| One in three Americans is obese, due in part to the increasing prevalence of fast-good restaurants and the popularity of sedentary activities such as playing video games. \| \| Hemline theory contends that women’s skirt lengths predict stock market increases and declines. The idea was born in the 1920s when economist George Taylor noticed that many women raised their skirts to reveal their silk stockings when times were good, but lowered their skirts to hide the fact that they weren’t wearing stockings when times were tough. \| \| The tendency to collect material items while being reluctant to throw them away has led to a rise in self-storage outlets as well as awareness of a hoarding epidemic. \| Table 3.4 Social Factors. Examples of several key trends representing social factors in the general environment are illustrated above. Sometimes changes in the social segment arise from unexpected sources. Before World War II, the American workforce was overwhelmingly male. When millions of men were sent to Europe and Asia to fight in the war, however, organizations had no choice but to rely heavily on female employees. At the time, the attitudes of many executives toward women were appalling. Consider, for example, some of the advice provided to male supervisors of female workers in the July 1943 issue of Transportation Magazine:1 - Older women who have never contacted the public have a hard time adapting themselves and are inclined to be cantankerous and fussy. It’s always well to impress upon older women the importance of friendliness and courtesy. - General experience indicates that “husky” girls—those who are just a little on the heavy side—are more even tempered and efficient than their underweight sisters. - Give every girl an adequate number of rest periods during the day. You have to make some allowances for feminine psychology. A girl has more confidence and is more efficient if she can keep her hair tidied, apply fresh lipstick and wash her hands several times a day. The tremendous contributions of female workers during the war contradicted these awful stereotypes. The main role of women who assembled airplanes, ships, and other war materials was to support the military, of course, but their efforts also changed a lot of male executives’ minds about what females could accomplish within organizations if provided with opportunities. Inequities in the workplace still exist today, but modern attitudes among men toward women in the workplace are much more enlightened than they were in 1943. Women’s immense contributions to the war effort during World War II helped create positive social changes in the ensuing decades. Wikimedia Commons – public domain. Beyond being a positive social change, the widespread acceptance of women into the workforce has created important opportunities for certain organizations. Retailers such as Talbot’s and Dillard’s sell business attire to women. Subway and other restaurants benefit when the scarceness of time lead dual income families to purchase take-out meals rather than cook at home. A surprising demographic trend is that both China and India have more than twice as many English-speaking college graduates each year than does the United States. T Is for “Technological” The technological segment centers on improvements in products and services that are provided by science. Relevant factors include, for example, changes in the rate of new product development, increases in automation, and advancements in service industry delivery. One key feature of the modern era is the ever-increasing pace of technological innovation. In 1965, Intel cofounder Gordon E. Moore offered an idea that has come to be known as Moore’s law. Moore’s law suggests that the performance of microcircuit technology roughly doubles every two years. This law has been very accurate in the decades since it was offered. \| Unsuccessful technological innovations such a Smell-O-Vision (a system that would release different odors that matched the events shown on screen) highlight the risk associated with the technology sector. Image watching a show on horse stables! \| \| The adoption rate of new technology is closely monitored by market research firms. The Internet reached 50 million users in 4 years. To reach the same number of users took 13 years for TV and 38 years for radio. \| \| The dramatic changes in the video game industry over the past 25 years highlight the need to constantly adapt to technological factors to maintain market leadership. Once-mighty Atari has given way to current leaders Sony, Nintendo, and Microsoft. \| \| Moore’s law suggests that the performance of microcircuit technology roughly doubles every two years. \| \| The amount of government spending for research and development affects numerous industries. The government’s decision to dramatically scale back moon-based space programs may reduce the pace of scientific breakthroughs. \| Table 5 Technological Factors. Examples of several key trends representing technological factors in the general environment are illustrated above. One implication of Moore’s law is that over time electronic devices can become smaller but also more powerful. This creates important opportunities and threats in a variety of settings. Consider, for example, photography. Just a decade ago, digital cameras were relatively large and they produced mediocre images. With each passing year, however, digital cameras have become smaller, lighter, and better. Meanwhile, film photography icon Kodak has been forced to abandon products that had been successful for decades. In 2005, the firm announced that it would stop producing black-and-white photographic paper. Four years later, Kodachrome color film was phased out. Successful technologies are embraced at a much faster rate than in earlier generations. The Internet reached fifty million users in only four years. In contrast, television reached the same number of users in thirteen years and radio thirty-eight years. This trend creates great opportunities for organizations that depend on emerging technologies. Writers of applications for Apple’s iPad and other tablet devices, for example, are able to target a fast-growing population of users. At the same time, organizations that depend on technologies that are being displaced must be aware that consumers could abandon them at a very rapid pace. As more and more Internet users rely on Wi-Fi service, the demand for cable modems may plummet. Although the influence of the technological segment on technology-based companies such as Panasonic and Apple is readily apparent, technological trends and events help to shape low-tech businesses too. In 2009, Subway started a service called Subway Now. This service allows customers to place their orders in advance using text. By offering customers this service, Subway is also responding to a trend in the general environment’s social segment: the need to save time in today’s fast-paced society. E Is for “Environmental” The environmental segment involves the physical conditions within which organizations operate. It includes factors such as natural disasters, pollution levels, and weather patterns. The threat of pollution, for example, has forced municipalities to treat water supplies with chemicals. These chemicals increase the safety of the water but detract from its taste. This has created opportunities for businesses that provide better-tasting water. Rather than consume cheap but bad-tasting tap water, many consumers purchase bottled water. Indeed, according to the Beverage Marketing Corporation, the amount of bottled water consumed by the average American increased from 1.6 gallons in 1976 to 28.3 gallons in 2006 (Earth911). At present, roughly one-third of Americans drink bottled water regularly. \| The Subaru automotive plant in Lafayette, Indiana, was the first auto manufacturing facility to achieve zero landfill status. \| \| Debate has raged over climate change in recent years. To the extend that more policy markers and consumers believe that human activity is increasing temperatures on the Earth, opportunities could increase for solar energy companies. \| \| Individuals embracing the three Rs of green living–reduce, reuse, recycle–has fueled new business concepts such as Recycle Match, a firm that brings together waste products with businesses that need those materials. \| \| Concern about the environmental effects of burning fossil fuels has contributed to the growing popularity of scooters. \| \| The increase in the number of food cooperatives reflects growing interest in sustainable, natural foods that are produced with a high degree of social responsibility. \| Table 6 Environmental Factors Examples of several key trends representing enviornmental factors in the general environment are illustrated above. As is the case for many companies, bottled water producers not only have benefited from the general environment but also have been threatened by it. Some estimates are that 80 percent of plastic bottles end up in landfills. This has led some socially conscious consumers to become hostile to bottled water. Meanwhile, water filtration systems offered by Brita and other companies are a cheaper way to obtain clean and tasty water. Such systems also hold considerable appeal for individuals who feel the need to cut personal expenses due to economic conditions. A key trend within the environmental segment is an increasing emphasis on conserving fossil fuels. L Is for “Legal” The legal segment centers on how the courts influence business activity. Examples of important legal factors include employment laws, health and safety regulations, discrimination laws, and antitrust laws. Intellectual property rights are a particularly daunting aspect of the legal segment for many organizations. When a studio such as Pixar produces a movie, a software firm such as Adobe revises a program, or a video game company such as Activision devises a new game, these firms are creating intellectual property. Such firms attempt to make profits by selling copies of their movies, programs, and games to individuals. Piracy of intellectual property—a process wherein illegal copies are made and sold by others—poses a serious threat to such profits. Law enforcement agencies and courts in many countries, including the United States, provide organizations with the necessary legal mechanisms to protect their intellectual property from piracy. \| Electronic recycling laws are creating opportunities for “green collar jobs.” A recent Missouri law, for example, requires computer electronic equipment manufacturers to develop and implement recycling plans. \| \| The Sherman Antitrust Act of 1890 limits cartels and monopolies in the United States. Senator John Sherman was the principal author of this legislation. \| \| In the United States, it is illegal to discriminate against anyone based on age, race, religion, gender or disability. \| \| The role of the Occupational Safety and Health Administration (OSHA) is to prevent work-related injuries, diseases, and fatalities by enforcing standards for workplace safety and health. \| \| Laws requiring that nutrition information must appear on the packaging of most food products are intended to protect consumers and help them make informed choices. \| Table 7 Legal Factors. Examples of several key trends representing legal factors in the general environment are illustrated below In other countries, such as China, piracy of intellectual property is quite common. Three other general environment segments play a role in making piracy a major concern. First, in terms of the social segment, China is the most populous country in the world. Second, in terms of the economic segment, China’s affluence is growing rapidly. Third, in terms of the technological segment, rapid advances in computers and communication have made piracy easier over time. Taken together, these various general environment trends lead piracy to be a major source of angst for firms that rely on intellectual property to deliver profits. A key legal trend in recent years is forcing executives to have greater accountability for corporate misdeeds via laws such as the 2002 Sarbanes-Oxley Act. Reproduced with permission from SONY DSC References Earth911, Plastic recycling facts. earth911.com. Retrieved from http://earth911.com/recycling/plastic/plastic-bottle-recycling-facts Mastering Strategic Management by University of Minnesota is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License, except where otherwise noted.	5,319	common-pile/pressbooks_filtered	https://pressbooks.usnh.edu/ld823/chapter/10/	pressbooks	pressbooks-0000.json.gz:36987	https://pressbooks.usnh.edu/ld823/chapter/10/
1-e19KUv9w4ASIsC	Art and Visual Culture: Prehistory to Renaissance	Broadly defined, iconoclasm is defined as the destruction of images. In Christianity, iconoclasm has generally been motivated by people who adopt a literal interpretation of the Ten Commandments, which forbid the making and worshipping of graven images. The period after the reign of Justinian I (527–565) witnessed a significant increase in the use and veneration of images, which helped to trigger a religious and political crisis in the empire. As a result, aniconic sentiment grew, culminating in two periods of iconoclasm—the First Iconoclasm (726–87) and the Second Iconoclasm (814–42)—which brought the Early Byzantine period to an end. Byzantine Iconoclasm constituted a ban on religious images by Emperor Leo III and continued under his successors. It was accompanied by the widespread destruction of images and persecution of supporters of the veneration of images. The goal of the iconoclasts was to restore the church to a strict opposition to images in worship that they believed characterized at the least some parts of the early church. The Feast of Orthodoxy After the death of the last Iconoclast emperor Theophilos, his young son Michael III, with his mother the regent Theodora and Patriarch Methodios, summoned the Synod of Constantinople in 843 to bring peace to the Church. At the end of the first session, on the first day of Lent, all made a triumphal procession from the Church of Blachernae to Hagia Sophia to restore the icons to the church in an event called the Feast of Orthodoxy. Imagery, it was decided, is an integral part of faith and devotion, making present to the believer the person or event depicted on them. However, the Orthodox makes a clear doctrinal distinction between the veneration paid to icons and the worship which is due to God alone. Since Iconoclasm was the last of the great Christological controversies to trouble the Church, its defeat is considered to be the final triumph of the Church over heresy. When the Iconoclasm controversy came to an end in 843, Byzantine religious art underwent a renewal. A series of naturalistic innovations can be seen in examples from the Hagia Sophia, the monastery of Hosios Loukas, and Saint Mark’s Basilica. This revival of a classical style of art was partly due to a renewed interest in classical culture, which accompanied a period of military successes, during the Macedonian Renaissance (867–1056). Theotokos Mosaic at the Hagia Sophia The Hagia Sophia is a former Greek Orthodox patriarchal basilica (church), constructed from 537 until 1453. A combination of a centrally planned and basilican building, it is considered the epitome of Byzantine architecture. After the end of iconoclasm, a new mosaic was dedicated in the Hagia Sophia under the Patriarch Photius and the Macedonian emperors Michael III and Basil I. The mosaic is located in the apse over the main altar and depicts the Theotokos or the Mother of God. An inscription reads: “The images which the impostors had cast down here, pious emperors (Michael and Basil) have again set up.” This inscription refers to the recent past and the renewal of Byzantine art under the Macedonian emperors. The image of the Virgin and Child is a common Christian image, and the mosaic depicts Byzantine innovations and the standard style of the period. The Virgin’s lap is large. Christ sits nestled between her two legs. The figures’ faces are depicted with gradual shading and modelling that provides a sense of realism that contradicts the schematic folding of their drapery. Their drapery is defined by thick, harsh folds delineated by contrasting colours: the Virgin in blue and Christ in gold. The two frontal figures sit on an embellished gold throne that is tilted to imply perspective. This attempt is a new addition to Byzantine art during this period. The space given to the chair contradicts the frontality of the figures, but it provides a sense of realism previously unseen in Byzantine mosaics. Hosios Loukas, Greece The monastery of Hosios Loukas (St. Luke) in Greece was founded in the early tenth century to host the relics of St. Luke. Located on the slope of Mount Helicon, the monastery is known for its two churches, the Church of the Theotokos (tenth century) and the main building called the Katholikon (eleventh century). The churches were decorated in mosaics, frescoes, and marble revetment. The two churches are connected together by the narthex of the Theotokos and an arm of the Katholikon. The churches demonstrate two different styles of architecture. Church of the Theotokos and the Katholikon The Church of the Theokotos represents a Greek cross-plan style church. It has a large central dome that rests on a series of pendentives. The Katholikon is also a Greek cross-plan style church but instead of the dome resting on pendentives, the dome of the Katholikon rests on squinches, which create an octagonal transition between the square plan of the church and the circular plan of the dome. The difference in style between the pendentives and the squinches allow for different relationships between the architecture and the decoration and different play of light and darkness in the shapes the squinches provided. The mosaics found in the Katholikon were created in an early Byzantine style commonly seen in the centuries before Iconoclasm. The scenes depicted are flat with little architecture or props to provide a setting. Instead, the background is covered in brilliant gold mosaics. The figures in the scenes, such as those seen in the apse mosaic of Christ washing the feet of his disciples, are depicted with naturalistic faces that are modelled with long, narrow noses and small mouths. The clothing of the figures is represented through schematic folds and contrasting colours. While the folds of the drapery represent a body underneath, there appears to be no actual mass to the body. These characteristics of Byzantine mosaics began to change in the following century, partially through the addition of perspective in the Theokotos of the Hagia Sophia. Saint Mark’s Basilica, Venice Saint Mark’s Basilica in Venice, Italy, was first built in the ninth century and rebuilt in the eleventh century in its current form following a fire. The basilica is a grand building, built next to the Doge’s Palace. It initially functioned as the doge’s private chapel, then a state church, and in 1806 became the city’s cathedral. The basilica houses the remains of Saint Mark, which the Venetians looted from Alexandria in 828 and prompted the building of the basilica. Saint Mark’s Basilica was built in the Byzantine Greek-cross plan. Each arm is divided into three naves and topped by a dome. At the crossing is a large central dome. The main apse is flanked by two smaller chapels. The narthex of the basilica is U-shaped and wraps around the western transept. It is decorated with scenes from the lives of Old Testament prophets. The entirety of the basilica is richly decorated. The floor is covered in geometric patterns and designs that use the Roman decoration techniques known as opus sectile and opus tessellatum. The lower walls and pillars are covered in marble polychromatic panels, and the upper walls and the domes are decorated with twelfth- and thirteenth-century mosaics. The central dome depicts an image of Christ Pantocrator, and the overall decorative program depicts scenes from the life of Christ and images of salvation from both the Old and New Testament. Objects of Worship in the Middle Byzantine Empire Personal objects (psalters and triptychs), reliquaries, and icons were popular objects of worship during the Middle Byzantine period. Triptych Triptychs are a type of panel painting or relief carving for devotional objects that are created on three panels. The panels could also be divided in two, known as diptychs, or sometimes had more than three panels, known as a polyptych. The use of triptychs began in the Byzantine period, and they were originally made to be small and portable. Later during the Gothic period, multi-panel devotional paintings were enlarged as altarpieces. However, the small, portable triptychs of the Byzantine period were used as personal objects of worship. They were designed to guide their owner in prayer and direct their thoughts towards Christ. The triptych was designed with one central panel and two wings that folded over the main image and allowed the object to be portable when closed, and to stand when the wings were open. The wings are typically carved with portrayals of saints, while the main image often depicted Christ, although the imagery varied. The Harbaville Triptych depicts a scene of Deesis with Christ as the Pantocrator, while the Borradaile Triptych depicts an image of the Crucifixion. Harbaville Triptych The Harbaville Triptych is an early example from the mid-tenth century of the new ivory triptychs that replaced diptychs during the Middle Byzantine period. The main scene depicts the figures of Christ Pantocrator flanked by John the Baptist and the Virgin Mary, in a supplication scene known as a Deesis. John the Baptist and the Virgin Mary are depicted as intercessors, praying on behalf of the triptych’s owner to Christ. On the register below them are the apostles James, John, Peter, Paul, and Andrew. The two side panels depict two registers with two characters each, all of which are identifiable saints. The figures are carved in a recognizably Byzantine style. Their bodies are elongated and narrow, and they seem to float or hover just above the ground instead of standing with weight. This illusion is furthered by the fact that nearly every character stands on a small platform. The saints are elegantly draped, and their bodies are distinguished by the folds of their drapery and not any type of modelling. The figures’ facial expressions are solemn, and their facial features are deeply carved. The saints each face outward, except for John the Baptist and the Virgin Mary, who are each slightly turned and bowing to an enthroned Christ. Christ sits on an elaborate throne as the Pantocrator, with a book of Gospels in one arm and his hand gesturing in a motion of blessing. Borradaile Triptych The Borradaile Triptych’s main image depicts the Crucifixion of Christ instead of a Deesis. The central image takes up the entirety of the main frame and the two wings are divided into three registers. The figures on the wings are images of saints, similar to the Harbaville Triptych. The central scene is dominated by the image of Christ on the cross. Two angels flank him above his arms. Below are the figures of the Virgin Mary and St. John. St. John gestures and averts his eyes, while Mary lifts a veil to her face, which bears a distraught expression. The figures, like those of the Harbaville Triptych, are elongated, although less narrow and more rigid. They also are less deeply carved and appear more insubstantial. Except for Christ’s upper body, which is unclothed, the bodies of the figures are defined by their rigid drapery. The saints stand in straight, upright positions that further provide a sense of solemnity to the scene. Christ is seen on the cross in a stance that focuses on his divine qualities and not his human suffering. The only emotion from the scene derives from his mother, the Virgin Mary, who stands weeping beneath him. Reliquaries A reliquary is a protective container used for the storage and display of sacred objects called relics. Relics were a part of the body of a dead saint that was preserved for veneration. Some relics are believed to be endowed with miraculous powers, and other relics have come to play key roles in certain church festivals. The veneration of relics and the use of reliquaries became popular during the Byzantine period when the bodies of saints were often moved and divided between Churches. While many relics were honoured and venerated, the church never considered this form of devotion as a form of worship—that was an act reserved for God. Reliquaries take many forms and shapes and are made out of a variety of materials. However, many reliquaries were made from or decorated with expensive material, such as gold and precious stones. A reliquary from the early ninth century depicts a scene of the Crucifixion with fourteen saints around the border. The reliquary is very small and probably contained a piece of the True Cross, the cross on which Christ was crucified. This reliquary is made from cloisonné, a metalworking technique in which metal was soldered into compartments and was then filled with enamel, glass, gems, or other materials. This reliquary is made with green, white, blue, and red enamel and gold and is only four inches high by nearly three inches wide. Psalters Like triptychs, psalters were small, private objects used for private devotion and worship. A psalter is a book that contains the Book of Psalms and other liturgical material such as calendars. They were often commissioned and were richly decorated and illuminated. The surviving psalters contain many fine examples of the painting styles and techniques from the Middle Byzantine period. The Paris Psalter is a mid-tenth century manuscript with fourteen, full-page, miniature paintings created in a classical style. As with most of the art produced under the Macedonian Dynasty, the figures and subject matter were influenced by a revived interest in classical culture. The figures painted in these scenes have bodies with mass and drapery that conforms rather than shapes, their bodies. The image depicts David, a psalmist, in an idyllic country setting outside a city (seen in the distance) composing psalms on his harp. He sits with a sheep, goats, dogs, and an angel, representing Melody, while a personification of Echo peers around a column. A male figure, representing the mountain of Bethlehem, lounges on the ground. The image is reminiscent of a Greco-Roman wall painting of the musician Orpheus charming people and animals with his music. While the figures appear modelled and are reminiscent of classical art, the psalter has a Byzantine style to it. The clothing is still rendered with bright, contrasting colours and the folds of the drapery are stylized and dark. The slightly skewed perspective given to the vase on top of the column and the city in the background are additional elements that provide the scene with a Byzantine artistic style. Icons Icons remained as popular devotional objects during the Byzantine period. These objects, which varied in size, depicted the image of a saint, or a sacred person such as Christ or Mary, who was considered sacred and was venerated. The images were often painted panels and the display of icons surged following the end of Iconoclasm in the ninth century. Many icons, once reaching this status, would be furthered objectified and protected through the addition of custom gilded frames, or gold or silver cases that covered the entirety of the image except for the face of the subject. Other icons, such as a ninth-century depiction of the Crucifixion, contained imagery on both sides. Painting in the Middle Byzantine Empire Painting during the Middle Byzantine period began to progress and change stylistically. Artists approached common scenes with an ingenuity based on a mix of naturalism in the conveyance of emotional reaction, and schematics in specific renderings of the body. This can be seen in the fresco of the Lamentation found in the Church of Saint Panteleimon in the city of Nerezi, Macedonia, an illumination of the Death of St. Onesimus, and an icon of the Virgin and Child. Lamentation from Saint Panteleimon, Nerezi, Macedonia The Lamentation of Christ is an iconic scene that depicts the Virgin Mary holding and mourning her dead son, just after Christ has been removed from the cross. She wraps an arm around his shoulders and presses her face against his. St. John grasps Christ’s right hand while Joseph of Arimathea and Nicodemus kneel at Christ’s feet. A fifth follower enters the scene with arms outstretched from the right and a group of angels fly above the scene in the deep blue sky. The Macedonian painters created a scene filled with emotional tension that was unprecedented in Byzantine art. The figures’ faces are neither solemn nor formal but instead are emotionally charged with grief and sorrow. The figures are also bent over Christ’s body, which further emphasizes the emotions in the scene—no longer stiff or static, these figures feel and cause the viewer to be filled with emotion. Despite these elements of naturalism, there are some elements of Byzantine style in the fresco. For one, the figures’ clothing is still schematically rendered, even though most of the figures appear to have bodies and mass under their garments. For another, the seminude body of Christ is rendered in a style similar to the drapery. The muscles are defined through schematic lines that denote parts of his body, such as his knees and abdominal muscles. Another oddity is that Christ’s body is not on the ground but instead hovers unnaturally off the ground. This is hardly noticed at first since the placement of his torso and feet make sense in their individual context, but as a whole, it requires Christ’s body to float instead of lay naturally on the ground. The Death of St. Onesimus A similar mixture of naturalism and stylization is evident in a painting that depicts the martyrdom of Saint Onesimus (c. 985 CE). The image is part of the Menologion of Basil II, an illuminated manuscript compiled circa 1000 CE as a church calendar. The Epistle to Philemon, written by Paul the Apostle to the slave-master Philemon, concerns a runaway slave called Onesimus. This slave found his way to the site of Paul’s imprisonment to escape punishment for a theft of which he was accused. After hearing the Gospel from Paul, Onesimus converted to Christianity. Paul, having earlier converted Philemon to Christianity, sought to reconcile the two by writing the letter to Philemon which today exists in the New Testament. During the reign of the Roman emperor Domitian and the persecution of Trajan, Onesimus was imprisoned in Rome and might have been martyred by stoning, although some sources claim that he was beheaded. As in the Lamentation scene above, the Death of St. Onesimus combines the naturalistic and the schematic. The two men who beat Onesimus to death convey a sense of dynamism as they bend at the waists and knees. The folds of their clothing and of Onesimus’s loincloth follows the contours of their bodies as they assume their poses. Although the painting is damaged, Onesimus’s furrowed brow, possibly suggesting anger or frustration, is still visible. Despite these realistic elements, the folds of the figures’ clothing appear more linear than natural, defined by deep, noticeable lines. Like the figure of Christ in the Lamentation, Onesimus seems to hover over the landscape and rest the top half of his body on the leg of one of his attackers. Furthermore, the blood pours from his legs in a linear manner, appearing more like strings than liquid. Theotokos of Vladimir The Theotokos of Vladimir, an icon of the Virgin and Child, represents the new style of icons that were created in the eleventh and twelfth centuries. These icons depict emotion, compassion, and the growing trend in spirituality. The mother and child are depicted with serene faces in the Byzantine style. Mary’s nose is long and narrow and her mouth small. She looks out and confronts the viewer with compassionate, knowing eyes that remind the viewer of Christ’s future sacrifice. The Christ child is small, although his face is adult-like and he is drawn to his mother and embraces her. His drapery shines as if it was golden rays, and the Virgin is dressed in rich, dark fabric with gold embellishments. The compassion and humanity between the characters prefigure the emotional Late Byzantine style of the next two centuries. The image was given as a gift to the Grand Duke of Kiev in 1131 by the Greek Patriarch of Constantinople and is an important and protective icon of the Russian cities of Vladimir and Moscow and the country of Russia itself.	4,322	common-pile/pressbooks_filtered	https://pressbooks.bccampus.ca/cavestocathedrals/chapter/middle-byzantine/	pressbooks	pressbooks-0000.json.gz:74174	https://pressbooks.bccampus.ca/cavestocathedrals/chapter/middle-byzantine/
vWF-UjDUzea-oQ7I	Agent-Based Evolutionary Game Dynamics	Part III. Spatial interactions on a grid III-3. Extension to any number of strategies 1. Goal Our goal here is to extend the model we have created in the previous chapter –which accepted games with 2 strategies only– to model (2-player symmetric) games with any number of strategies. 2. Motivation. Spatial Hawk-Dove-Retaliator The model we are going to develop in this chapter will allow us to explore games with any number of strategies. Thus, we will be able to model games like the classical Hawk-Dove-Retaliator (Maynard Smith, 1982, pp. 17-18), which is an extension of the Hawk-Dove game, with the additional strategy Retaliator. Retaliators are just like Doves, except in contests against Hawks. When playing against Hawks, Retaliators behave like Hawks. A possible payoff matrix for this symmetric game is the following: \| Hawk (H) \| Dove (D) \| Retaliator (R) \| \| \| Hawk (H) \| -1 \| 2 \| -1 \| \| Dove (D) \| 0 \| 1 \| 1 \| \| Retaliator (R) \| -1 \| 1 \| 1 \| Let us consider the population game where agents are matched to play the normal form game with payoffs as above.[1] The only Evolutionarily Stable State (ESS; see Thomas (1984) and Sandholm (2010a, section 8.3)) of this population game is the state (½H + ½D), with half the population playing Hawk and the other half playing Dove (Maynard Smith, 1982, appendix E; Binmore, 2013). Also, note that Retaliators are weakly dominated by Doves: they get a strictly lower expected payoff than Doves in any situation, except in those population states with no Hawks whatsoever (at which retaliators get exactly the same payoff as Doves). Figure 1 below shows the best response correspondence of this game. Population states are represented in a simplex, and the color at any population state indicates the strategy that provides the highest expected payoff at that state: orange for Hawk, green for Dove, and blue for Retaliator. As an example, the population state where the three strategies are equally present, i.e. (⅓H + ⅓D +⅓R), which lies at the barycenter of the simplex, is colored in green, denoting that the strategy that provides the highest expected payoff at that state is Dove. We would like to study the dynamic stability of the unique ESS (½H + ½D) in spatial contexts. In unstructured populations, ESSs are asymptotically stable under a wide range of revision protocols (see e.g. Sandholm (2010a, theorem 8.4.7)), and in particular under the best response rule. Therefore, one might be tempted to think that in our spatial model with the imitate the best neighbor rule (including some noise to allow for the occasional entry of any strategy), simulations will tend to spend most of the time around the unique (½H + ½D) and Retaliators would hardly be observed. This hypothesis may be further supported by the fact that the area around the unique ESS where Retaliators are suboptimal is quite sizable. In no situation can Retaliators obtain a higher expected payoff than Doves, and departing from the unique ESS, at least one half of the population would have to be replaced (i.e. all the Hawks) for Retaliators to get the same expected payoff as Doves. Having seen all this, it may come as no surprise that if we simulate this game with the random-matching model we implemented in Part II, retaliators tend to disappear from any interior population state. The following video shows an illustrative simulation starting from a situation where all agents are retaliators (and including some noise to allow for the entry of any strategy).[2] So, will space give Retaliators any chance of survival? Let’s build a model to explore this question! 3. Description of the model The model we are going to develop here is a generalization of the model implemented in the previous chapter. The new model will have a new parameter, payoffs, that the user can set to input a payoff matrix of the form [ [A00 A01 … A0n] [A10 A11 … A1n] … [An0 An1 … Ann] ], containing the payoffs Aij that an agent playing strategy i obtains when meeting an agent playing strategy j (i, j ∈ {0, 1, …, n}). The number of strategies will be inferred from the number of rows in the payoff matrix. The user will also be able to set any initial conditions using parameter n-of-players-for-each-strategy, which will be a list of the form [a0 a1 … an], where item ai is the initial number of agents playing strategy i. Naturally, the sum of all the elements in this list should equal the number of patches in the world. Everything else stays as described in the previous chapter. 4. Interface design We depart from the model we developed in the previous chapter (so if you want to preserve it, now is a good time to duplicate it). The new interface (see figure 2 above) requires the following modifications: - Remove the sliders for parameters CC-payoff, CD-payoff, DC-payoff, DD-payoff, and initial-%-of-C-players. Since these sliders were our way of declaring the corresponding global variables, you will now get all sorts of errors, but don’t panic, we will sort them out later. - Remove the button labeled . Yes, more errors, but let us do our best to stay calm; we will fix them in a little while. - Add an input box for parameter payoffs. Create an input box with associated global variable payoffs. Set the input box type to “String (reporter)” and tick the “Multi-Line” box. Note that the content of payoffs will be a string (i.e. a sequence of characters) from which we will have to extract the payoff numeric values. - Create an input box to let the user set the initial number of players using each strategy. Create an input box with associated global variable n-of-players-for-each-strategy. Set the input box type to “String (reporter)”. - Remove the “pens” in the Strategy Distribution plot. Since the number of strategies is unknown until the payoff matrix is read, we will need to create the required number of “pens” in the Code tab. Edit the Strategy Distribution plot and delete both pens. - We have also modified the monitor. Before it showed the ticks and now it shows the number of players (i.e. the value of a global variable named n-of-players, to be defined shortly). You may want to do this or not, as you like. 5. Code 5.1. Skeleton of the code 5.2. Global variables and individually-owned variables First of all, we declare the global variables that we are going to use and we have not already declared in the interface. We will be using a global variable named payoff-matrix to store the payoff values on a list. It will also be handy to have a variable store the number of strategies and another variable store the number of players. Since this information will likely be used in various procedures and will not change during the course of a simulation, it makes sense to define the new variables as global. The natural names for these two variables are n-of-strategies and n-of-players: globals [ payoff-matrix n-of-strategies n-of-players ] Now we focus on the patches-own variables. We are going to need each individual patch to store its strategy and its strategy-after-revision. These two variables replace the previous C-player? and C-player?-after-revision. Thus, the code for patches-own variables looks as follows now: patches-own [ ;; C-player? <== no longer needed ;; C-player?-after-revision <== no longer needed strategy ;; <== new variable strategy-after-revision ;; <== new variable payoff my-nbrs-and-me my-coplayers n-of-my-coplayers ] 5.3. Setup procedures The current setup procedure looks as follows: to setup clear-all setup-players ask patches [update-color] reset-ticks end Clearly we will have to keep this code, but additionally we will have to set up the payoffs and set up the graph (since the number of pens to be created depends on the payoff matrix now). To do this elegantly, we should create separate procedures for each set of related tasks; to setup-payoffs and to setup-graph are excellent names for these new procedures. Thus, the code of procedure to setup should include calls to these new procedures: to setup clear-all setup-payoffs ;; <== new line setup-players setup-graph ;; <== new line reset-ticks update-graph ;; <== new line ask patches [update-color] end Note that we have also included a call to another new procedure named to update-graph, to plot the initial conditions.[3] The code of procedure to setup in this model looks almost identical to the code of the same procedure in the model we developed in Part II. As a matter of fact, we will be able to reuse much of the code we wrote for that model. Let us now implement procedures to setup-payoffs, to setup-graph and to update-graph. We will also have to modify procedures to setup-players and to update-color. to setup-payoffs The procedure to setup-payoffs will include the instructions to read the payoff matrix, and will also set the value of the global variable n-of-strategies. Looking at the implementation of the same procedure in the model we developed in Part II, can you implement procedure to setup-payoffs for our new model? Implementation of procedure to setup-payoffs. Yes, well done! We can use exactly the same code! to setup-payoffs set payoff-matrix read-from-string payoffs set n-of-strategies length payoff-matrix end to setup-players The current procedure to setup-players looks as follows: to setup-players ask patches [ set payoff 0 set C-player? false set C-player?-after-revision false set my-nbrs-and-me (patch-set neighbors self) set my-coplayers ifelse-value self-matching? [my-nbrs-and-me] [neighbors] set n-of-my-coplayers (count my-coplayers) ] ask n-of (round (initial-%-of-C-players * count patches / 100)) patches [ set C-player? true set C-player?-after-revision true ] end This procedure will have to be modified substantially. In particular, the lines in bold in the code above include variables that do not exist anymore. But don’t despair! Once again, to modify procedure to setup-players appropriately, the implementation of the same procedure in the model we developed in Part II will be invaluable. Using that code, can you try to implement procedure to setup-players in our new model? Implementation of procedure to setup-players. The lines marked in bold below are the only modifications we have to make to the implementation of this procedure from Part II. to setup-players let initial-distribution read-from-string n-of-players-for-each-strategy if length initial-distribution != length payoff-matrix [ user-message (word "The number of items in\n" "n-of-players-for-each-strategy (i.e. " length initial-distribution "):\n" n-of-players-for-each-strategy "\nshould be equal to the number of rows\n" "in the payoff matrix (i.e. " length payoff-matrix "):\n" payoffs ) ] ask patches [set strategy false] let i 0 foreach initial-distribution [ j -> ask n-of j (patches with [strategy = false]) [ set payoff 0 set strategy i set strategy-after-revision strategy set my-nbrs-and-me (patch-set neighbors self) set my-coplayers ifelse-value self-matching? [my-nbrs-and-me] [neighbors] set n-of-my-coplayers (count my-coplayers) ] set i (i + 1) ] set n-of-players count patches end Finally, it would be a nice touch to warn the user if the total number of players in list n-of-players-for-each-strategy is not equal to the number of patches. One possible way of doing this is to include the code below, right before setting the patches’ strategies to false. if sum initial-distribution != count patches [ user-message (word "The total number of agents in\n" "n-of-agents-for-each-strategy (i.e. " sum initial-distribution "):\n" n-of-players-for-each-strategy "\nshould be equal to the number of patches (i.e. " count patches ")" ) ] to setup-graph The procedure to setup-graph will create the required number of pens –one for each strategy– in the Strategy Distribution plot. Looking at the implementation of the same procedure in the model we developed in Part II, can you implement procedure to setup-graph for our new model? Implementation of procedure to setup-graph. Yes, well done! We can use exactly the same code! to setup-graph set-current-plot "Strategy Distribution" foreach (range n-of-strategies) [ i -> create-temporary-plot-pen (word i) set-plot-pen-mode 1 set-plot-pen-color 25 + 40 * i ] end to update-graph Procedure to update-graph will draw the strategy distribution using a stacked bar chart, just like in the model we implemented in Part II (see figure 3 in chapter II-2). This procedure is called at the end of setup to plot the initial distribution of strategies, and will also be called at the end of procedure to go, to plot the strategy distribution at the end of every tick. Looking at the implementation of the same procedure in the model we developed in Part II, can you implement procedure to update-graph for our new model? Implementation of procedure to update-graph. Yes, well done! We only have to replace the word players in the previous code with patches in the current code. to update-graph let strategy-numbers (range n-of-strategies) let strategy-frequencies map [ n -> count patches with [strategy = n] / n-of-players ] strategy-numbers set-current-plot "Strategy Distribution" let bar 1 foreach strategy-numbers [ n -> set-current-plot-pen (word n) plotxy ticks bar set bar (bar - (item n strategy-frequencies)) ] set-plot-y-range 0 1 end to update-color Note that in the previous model, patches were colored according to the four possible combinations of values of C-player? and C-player?-after-revision. Now that there can be many strategies, it seems more natural to use one color for each strategy. It also makes sense to use the same color legend as in the Strategy Distribution plot (see procedure to setup-graph). Can you try and implement the new version of to update-color? Implementation of procedure to update-color. Here we go! to update-color set pcolor 25 + 40 * strategy end 5.4. Go procedure The current go procedure looks as follows: to go ifelse synchronous-updating? [ ask patches [ play ] ask patches [ update-strategy-after-revision ;; here we are not updating the agent's strategy yet update-color ] ask patches [ update-strategy ] ;; now we update every agent's strategy at the same time ] [ ask patches [ play ask my-coplayers [ play ] ;; since your coplayers' strategies or ;; your coplayers' coplayers' strategies ;; could have changed since the last time ;; your coplayers played update-strategy-after-revision update-color update-strategy ] ] tick end In the previous version of the model, the call to update-color had to be done in between the calls to update-strategy-after-revision and update-strategy. Now that the patches’ color only depends on their (updated) strategy, we should ask patches to run update-color at the end of procedure to go, after every patch has updated its strategy. Finally, recall that we also have to run update-graph at the end of procedure to go, to plot the strategy distribution at the end of every tick. Thus, the code of procedure to go will be as follows: to go ifelse synchronous-updating? [ ask patches [ play ] ask patches [ update-strategy-after-revision ] ;; here we are not updating the agent's strategy yet ask patches [ update-strategy ] ;; now we update every agent's strategy at the same time ] [ ask patches [ play ask my-coplayers [ play ] ;; since your coplayers' strategies or ;; your coplayers' coplayers' strategies ;; could have changed since the last time ;; your coplayers played update-strategy-after-revision update-strategy ] ] tick update-graph ;; <== new line ask patches [update-color] ;; <== new line end 5.5. Other procedures to play In procedure to play the patch has to compute its payoff. For that, the patch must count how many of its coplayers are using each of the possible strategies. We can count the number of coplayers that are using strategy i ∈ {0, 1, …, (n-of-strategies – 1)} as: count my-coplayers with [strategy = i] Thus, we just have to run this little function for each value of i ∈ {0, 1, …, (n-of-strategies – 1)} . This can be easily done using primitive n-values: n-values n-of-strategies [ i -> count my-coplayers with [strategy = i] ] The code above produces a list with the number of coplayers that are using each strategy. Let us store this list in local variable n-of-coplayers-with-strategy-?: let n-of-coplayers-with-strategy-? n-values n-of-strategies [ i -> count my-coplayers with [strategy = i] ] Now note that the relevant row of the payoff-matrix is the one at position strategy. We store this row in local variable my-payoffs: let my-payoffs (item strategy payoff-matrix) Finally, the payoff that the patch will get for each coplayer playing strategy i is the i-th element of the list my-payoffs, so we only have to multiply the two lists (my-payoffs and n-of-coplayers-with-strategy-?) element by element, and add up all the elements in the resulting list. To multiply the two lists element by element we use primitive map: sum (map * my-payoffs n-of-coplayers-with-strategy-?) With this, we have finished the code in procedure to play. to play let n-of-coplayers-with-strategy-? n-values n-of-strategies [ i -> count my-coplayers with [strategy = i] ] let my-payoffs (item strategy payoff-matrix) set payoff sum (map * my-payoffs n-of-coplayers-with-strategy-?) end to update-strategy-after-revision Right now, procedure to update-strategy-after-revision is implemented as follows: to update-strategy-after-revision set C-player?-after-revision ifelse-value (random-float 1 < noise) [ one-of [true false] ] [ [C-player?] of one-of (my-nbrs-and-me with-max [payoff]) ] end What changes do we have to make in this procedure? Implementation of procedure to update-strategy-after-revision. The only changes we have to make are highlighted in bold below: to update-strategy-after-revision set strategy-after-revision ifelse-value (random-float 1 < noise) [ random n-of-strategies ] [ [strategy] of one-of (my-nbrs-and-me with-max [payoff]) ] end to update-strategy Right now, procedure to update-strategy is implemented as follows: to update-strategy set C-player? C-player?-after-revision end What changes do we have to make in this procedure? Implementation of procedure to update-strategy. Keep up the excellent work! to update-strategy set strategy strategy-after-revision end 5.6. Complete code in the Code tab The Code tab is ready! globals [ payoff-matrix n-of-strategies n-of-players ] patches-own [ strategy strategy-after-revision payoff my-nbrs-and-me my-coplayers n-of-my-coplayers ] to setup clear-all setup-payoffs setup-players setup-graph reset-ticks update-graph ask patches [update-color] end to setup-payoffs set payoff-matrix read-from-string payoffs set n-of-strategies length payoff-matrix end to setup-players let initial-distribution read-from-string n-of-players-for-each-strategy if length initial-distribution != length payoff-matrix [ user-message (word "The number of items in\n" "n-of-players-for-each-strategy (i.e. " length initial-distribution "):\n" n-of-players-for-each-strategy "\nshould be equal to the number of rows\n" "in the payoff matrix (i.e. " length payoff-matrix "):\n" payoffs ) ] if sum initial-distribution != count patches [ user-message (word "The total number of agents in\n" "n-of-agents-for-each-strategy (i.e. " sum initial-distribution "):\n" n-of-players-for-each-strategy "\nshould be equal to the number of patches (i.e. " count patches ")" ) ] ask patches [set strategy false] let i 0 foreach initial-distribution [ j -> ask n-of j (patches with [strategy = false]) [ set payoff 0 set strategy i set strategy-after-revision strategy set my-nbrs-and-me (patch-set neighbors self) set my-coplayers ifelse-value self-matching? [my-nbrs-and-me] [neighbors] set n-of-my-coplayers (count my-coplayers) ] set i (i + 1) ] set n-of-players count patches end to setup-graph set-current-plot "Strategy Distribution" foreach (range n-of-strategies) [ i -> create-temporary-plot-pen (word i) set-plot-pen-mode 1 set-plot-pen-color 25 + 40 * i ] end to go ifelse synchronous-updating? [ ask patches [ play ] ask patches [ update-strategy-after-revision ] ;; here we are not updating the agent's strategy yet ask patches [ update-strategy ] ;; now we update every agent's strategy at the same time ] [ ask patches [ play ask my-coplayers [ play ] ;; since your coplayers' strategies or ;; your coplayers' coplayers' strategies ;; could have changed since the last time ;; your coplayers played update-strategy-after-revision update-strategy ] ] tick update-graph ask patches [update-color] end to play let n-of-coplayers-with-strategy-? n-values n-of-strategies [ i -> count my-coplayers with [strategy = i] ] let my-payoffs (item strategy payoff-matrix) set payoff sum (map * my-payoffs n-of-coplayers-with-strategy-?) end to update-strategy-after-revision set strategy-after-revision ifelse-value (random-float 1 < noise) [ random n-of-strategies ] [ [strategy] of one-of my-nbrs-and-me with-max [payoff] ] end to update-strategy set strategy strategy-after-revision end to update-graph let strategy-numbers (range n-of-strategies) let strategy-frequencies map [ n -> count patches with [strategy = n] / n-of-players ] strategy-numbers set-current-plot "Strategy Distribution" let bar 1 foreach strategy-numbers [ n -> set-current-plot-pen (word n) plotxy ticks bar set bar (bar - (item n strategy-frequencies)) ] set-plot-y-range 0 1 end to update-color set pcolor 25 + 40 * strategy end 5.7. Code inside the plots Note that we take care of all plotting in the update-graph procedure. Thus there is no need to write any code inside the plot. We could instead have written the code of procedure to update-graph inside the plot, but given that it is somewhat lengthy, we find it more convenient to group it with the rest of the code in the Code tab. 6. Sample runs Now that we have implemented the model we can explore the dynamics of the spatial Hawk-Dove-Retaliator game! Will Retaliators survive in a spatial context? Let us explore this question using the parameter values shown in figure 2 above. Unbelievable! Retaliators do not only survive, but they are capable of taking over about half the population. Is this observation robust? If you modify the parameters of the model you will see that indeed it is. The following video shows an illustrative run with noise = 0.05, synchronous-updating? = false and self-matching? = false. The greater level of noise means that more Hawks appear by chance. This harms Retaliators more than it harms Doves, but Retaliators still manage to stay the most prevalent strategy in the population. How can this be? First, note that even though the state where the whole population is choosing Retaliator is not an ESS, it is a Neutrally Stable State (Sandholm, 2010a, p. 82). And, crucially, it is the only pure state that is Nash (i.e. the only pure strategy that is best response to itself). Note that in spatial contexts neighbors face similar situations when playing the game (since their neighborhoods overlap). Because of this, it is often the case that neighbors choose the same strategy, and therefore clusters of agents using the same strategy are common. In the Hawk-Dove-Retaliator game, clusters of Retaliators are more stable than clusters of Doves (which are easily invadable by Hawks) and also more stable than clusters of Hawks (which are easily invadable by Doves). This partially explains the amazing success of Retaliators in spatial contexts, even though they are weakly dominated by Doves. 7. Exercises You can use the following link to download the complete NetLogo model: nxn-imitate-best-nbr.nlogo. Exercise 1. Killingback and Doebeli (1996, pp. 1140-1) explore the spatial Hawk-Dove-Retaliator-Bully game, with payoff matrix: [[ -1 2 -1 2] [ 0 1 1 0] [ -1 1 1 2] [ 0 2 0 1]] Do Retaliators still do well in this game? Exercise 2. Explore the beautiful dynamics of the following monocyclic game (Sandholm, 2010a, example 9.2.2, pp. 329-30): [[ 0 -1 0 0 1] [ 1 0 -1 0 0] [ 0 1 0 -1 0] [ 0 0 1 0 -1] [-1 0 0 1 0]] Compare simulations with balanced initial conditions (i.e. all strategies approximately equally present) and with unbalanced initial conditions (e.g. only one strategy present at the beginning of the simulation). What do you observe? Exercise 3. How can we parameterize our model to replicate the results shown in figure 4 of Killingback and Doebeli (1996, p. 1141)? Exercise 4. In procedure to play we compute the list with the number of coplayers that are using each strategy as follows: n-values n-of-strategies [ i -> count my-coplayers with [strategy = i] ] Can you implement the same functionality using the primitive map instead of n-values? Exercise 5. Reimplement the procedure to update-strategy-after-revision so the revising agent uses the imitative pairwise-difference rule adapted to networks, i.e. the revising agent looks at a random neighbor and copies her strategy only if the observed agent’s average payoff is higher than the revising agent’s average payoff; in that case, the revising agent switches with probability proportional to the payoff difference. - The payoff function of the associated population game is , where denotes the population state and denotes the payoff matrix of the normal form game. This population game can be obtained by assuming that every agent plays with every other agent. ↵ - The fact that the simulation tends to linger around the ESS is a coincidence, since the imitate if better rule depends only on ordinal properties of the payoffs. What is not a coincidence is that Retaliators (which are weakly dominated by Doves) are eliminated in the absence of noise (Loginov, 2021). ↵ - There is some flexibility in the order of the lines within procedure to setup. For instance, the call to procedure setup-graph could be made before or after executing reset-ticks. ↵	5,305	common-pile/pressbooks_filtered	https://wisc.pb.unizin.org/agent-based-evolutionary-game-dynamics/chapter/iii-3/	pressbooks	pressbooks-0000.json.gz:71794	https://wisc.pb.unizin.org/agent-based-evolutionary-game-dynamics/chapter/iii-3/
iu6WVYPnMQ9Oasje	Early World Civilizations	121 The Economy under the Ming Dynasty Learning Objective - Explain why the Ming dynasty supported the agricultural classes Key Points - The economy of the Ming dynasty (1368–1644) of China was the largest in the world during that period, but suffered many inflations and contractions of currency. - Because of hyperinflation of paper currency, the government returned to using silver as currency, which saw a major boom but later crashed, giving rise to widespread smuggling. - Both because of his upbringing as a poor peasant and in order to recover from the rule of the Mongols and the wars that followed, the Hongwu Emperor enacted pro-agricultural policies. - The Ming saw the rise of large commercial plantations, cash crops, and expanded markets. - Hongwu Emperor initiated extensive land reform, including the distribution of land to peasants. Terms autarkic The quality of being self-sufficient, especially in economic or political systems. bullion Gold bars, silver bars, and other bars or ingots of precious metal used as currency. Overview The economy of the Ming dynasty (1368–1644) of China was the largest in the world during that period. It is regarded as one of China’s three golden ages (the other two being the Han and Song periods). The period was marked by the increasing political influence of the merchants, the gradual weakening of imperial rule, and technological advances. Currency during the Ming Dynasty The early Ming dynasty attempted to use paper currency, with outflows of bullion limited by its ban on private foreign commerce. Like its forebears, paper currency experienced massive counterfeiting and hyperinflation. In 1425, Ming notes were trading at about 0.014% of their original value under the Hongwu Emperor. The notes remained in circulation as late as 1573, but their printing ceased in 1450. Minor coins were minted in base metals, but trade mostly occurred using silver ingots. As their purity and exact weight varied, they were treated as bullion and measured in tael. These privately made “sycee” first came into use in Guangdong, spreading to the lower Yangtze sometime before 1423, the year sycee became acceptable for payment of tax obligations. In the mid-15th century, the paucity of circulating silver caused a monetary contraction and an extensive reversion to barter. The problem was met through smuggled, then legal, importation of Japanese silver, mostly through the Portuguese and Dutch, and Spanish silver from Potosí carried on the Manila galleons. Silver was required to pay provincial taxes in 1465, the salt tax in 1475, and corvée exemptions in 1485. By the late Ming, the amount of silver being used was extraordinary; at a time when English traders considered tens of thousands of pounds an exceptional fortune, the Zheng clan of merchants regularly engaged in transactions valued at millions of taels. However, a second silver contraction occurred in the mid-17th century when King Philip IV of Spain began enforcing laws limiting direct trade between Spanish South America and China at about the same time the new Tokugawa shogunate in Japan restricted most of its foreign exports, cutting off Dutch and Portuguese access to its silver. The dramatic spike in silver’s value in China made payment of taxes nearly impossible for most provinces. The government even resumed use of paper currency amid Li Zicheng’s rebellion. Agriculture during the Ming Dynasty In order to recover from the rule of the Mongols and the wars that followed, the Hongwu Emperor enacted pro-agricultural policies. The state invested extensively in agricultural canals and reduced taxes on agriculture to 3.3% of the output, and later to 1.5%. Ming farmers also introduced many innovations such as water-powered plows, and new agricultural methods such as crop rotation. This led to a massive agricultural surplus that became the basis of a market economy. The Ming saw the rise of commercial plantations that produced crops suitable to their regions. Tea, fruit, paint, and other goods were produced on a massive scale by these agricultural plantations. Regional patterns of production established during this period continued into the Qing dynasty. The Columbian exchange brought crops such as corn. Still, large numbers of peasants abandoned the land to become artisans. The population of the Ming boomed; estimates for the population of the Ming range from 160 to 200 million. Agriculture during the Ming changed significantly. Firstly, gigantic areas devoted to cash crops sprung up, and there was demand for the crops in the new market economy. Secondly, agricultural tools and carts, some water powered, help to create a large agricultural surplus that formed the basis of the rural economy. Besides rice, other crops were grown on a large scale. Although images of autarkic farmers who had no connection to the rest of China may have some merit for the earlier Han and Tang dynasties, this was certainly not the case for the Ming dynasty. During the Ming dynasty, the increase in population and the decrease in quality land made it necessary for farmers to make a living off cash crops. Markets for these crops appeared in the rural countryside, where goods were exchanged and bartered. A second type of market that developed in China was the urban-rural type, in which rural goods were sold to urban dwellers. This was common when landlords decided to reside in the cities and use income from rural land holdings to facilitate exchange in those urban areas. Professional merchants used this type of market to buy rural goods in large quantities. The third type of market was the “national market,” which was developed during the Song dynasty but particularly enhanced during the Ming. This market involved not only the exchanges described above, but also products produced directly for the market. Unlike earlier dynasties, many Ming peasants were no longer generating only products they needed; many of them produced goods for the market, which they then sold at a profit. Land Reform As the Hongwu Emperor came from a peasant family, he was aware of how peasants used to suffer under the oppression of the scholar-bureaucrats and the wealthy. Many of the latter, relying on their connections with government officials, encroached unscrupulously on peasants’ lands and bribed the officials to transfer the burden of taxation to the poor. To prevent such abuse, the Hongwu Emperor instituted two systems: Yellow Records and Fish Scale Records. These systems served both to secure the government’s income from land taxes and to affirm that peasants would not lose their lands. However, the reforms did not eliminate the threat of the bureaucrats to peasants. Instead, the expansion of the bureaucrats and their growing prestige translated into more wealth and tax exemption for those in government service. The bureaucrats gained new privileges and some became illegal money-lenders and managers of gambling rings. Using their power, the bureaucrats expanded their estates at the expense of peasants’ land through outright purchase of those lands and foreclosure on their mortgages whenever they wanted the lands. The peasants often became either tenants or workers, or sought employment elsewhere. Since the beginning of the Ming dynasty in 1357, great care was taken by the Hongwu Emperor to distribute land to peasants. One way was through forced migration to less dense areas; some people were tied to a pagoda tree in Hongdong and moved. Public works projects, such as the construction of irrigation systems and dikes, were undertaken in an attempt to help farmers. In addition, the Hongwu Emperor also reduced the demands for forced labour on the peasantry. In 1370, the Hongwu Emperor ordered that some lands in Hunan and Anhui should be given to young farmers who had reached adulthood. The order was intended to prevent landlords from seizing the land, as it also decreed that the titles to the lands were not transferable. During the middle part of his reign, the Hongwu Emperor passed an edict stating that those who brought fallow land under cultivation could keep it as their property without being taxed.	1,706	common-pile/pressbooks_filtered	https://library.achievingthedream.org/herkimerworldcivilization/chapter/the-economy-under-the-ming-dynasty/	pressbooks	pressbooks-0000.json.gz:77467	https://library.achievingthedream.org/herkimerworldcivilization/chapter/the-economy-under-the-ming-dynasty/
t_F0gQxdVOy0vnHs	23 Scholarly Communication Things	Open Access Models Ginny Barbour; Paula Callan; and Stephanie Jacobs Getting Started Open Access Australasia describes open access as a set of principles and a range of practices through which research outputs are distributed online, free of cost or other access barriers. Through licensing via an open license (usually a Creative Commons License), freely available outputs can be legally shared and reused. It’s important to remember that open access is therefore more than free access. Open Access (OA) was first defined in a series of declarations in the early 2000s, the Budapest, Berlin and Bethesda declarations. The principles behind open access have not changed; to use the online environment to ensure equitable access to research outputs for all . An old tradition and a new technology have converged to make possible an unprecedented public good. The old tradition is the willingness of scientists and scholars to publish the fruits of their research in scholarly journals without payment, for the sake of inquiry and knowledge. The new technology is the internet. The public good they make possible is the world-wide electronic distribution of the peer-reviewed journal literature and completely free and unrestricted access to it by all scientists, scholars, teachers, students, and other curious minds. Open access publishing uses the same quality control – peer review – as do traditional journals. The change that open access supports is in the open method of dissemination; there is no difference in quality or rigor of content between subscription based and open access journals. Many large research funding bodies – including the Australian Research Council (ARC) and National Health and Medical Research Council (NHMRC) – now insist that an open access version of articles arising from their funded research is made available. Many universities also have open access policies. A list of open access policies in Australasia is compiled here. Benefits of Open Access Open access accelerates the pace of discovery by exposing research findings to a wider audience. By harnessing the power of networks to share research findings with practitioners who can apply the new knowledge, open access also accelerates the translation of research into benefits for the public. While open access is of enormous benefit to researchers, so too is it of benefit to wider audiences. Open access allows far more people to view research, compared with research in subscription journals. Readers could be anyone from researchers in other countries, to the public in a specific locality, and even policymakers . The impact of an open access scholarly work has the potential to be far greater than if it was in a subscription journal. The evolution that has occurred in the open access landscape has led to the many open access models now present today. This chapter discusses some of the various open access models available, and additional forms of research outputs beyond journal articles that are also available via open access models. Open Access Models Open access models are sometimes, and often confusingly, known by a colour. Generally, is it best practice to refer to specific model (eg repository- based or journal-based), rather than the colour, especially when talking with academics. The most important distinction in models is between repository-based and journal-based open access. However, for reference, definitions of the various colours of open access are provided below. Activity: Match the open access model to its short description: JOURNAL-BASED OPEN ACCESS The journal-based open access model is where the published version of a journal article (sometimes called the ‘Version of Record’) is freely available via the journal, immediately upon publication, and is licensed for re-use (generally via a Creative Commons License). In some, but not all, cases, the author may be required to pay an article processing charge (APC) in lieu of the revenue the publisher would otherwise recoup via subscriptions or pay-to-view access payments. However, more than 11,000 of the peer reviewed journals currently listed in the Directory of Open Access Journals do not charge an APC. This is made possible because the journals are supported by the host university or a scholarly society. This form of journal-based open access is sometimes referred to as ‘Diamond Open Access’. Many universities around the world are now publishing one or more ‘Diamond Open Access’ journals. For example, see the suite of journals published by Queensland University of Technology (QUT). Another variant of journal-based open access is the ‘hybrid’ model. This is where the authors pay an optional APC to have their article published open access in an otherwise subscription-based journal. Hybrid open access is rarely the preferred model of funders or institutions. REPOSITORY-BASED OPEN ACCESS Currently, the most commonly adopted open access model in Australia is repository-based open access. Also known as Green OA, this option involves authors sharing a copy of the ‘Accepted Manuscript’ version of their peer reviewed publications via an institutional repository such as QUT ePrints or a subject repository such as PubMed Central. The ‘Accepted Manuscript’ is sometimes called the ‘Accepted Version’ or AAM (Authors Accepted Manuscript) or the ‘Postprint’. By definition, this is the post-peer review version of the manuscript. It includes revisions made by the authors after peer review but, unlike the ‘Published Version’ it does not include post-acceptance enhancements contributed by the publisher such as copy-editing, formatting and reference-linking. Repository-based open access is free, legal and is currently compliant with all institutional and funder OA policies in Australia. Read more about the OA policy at QUT in their Manual of Policies and Procedures. Institutional repositories commonly include a diverse range of open access research outputs including reports, higher degree theses and datasets. Learn more As mentioned in the introduction, the open access landscape is a rapidly changing space. There is a continuing rise in the acceptance of open access by publishers and increased advocacy and support for open access by academic institutions, national groups such as Open Access Australasia and Council of Australian University Libraries (CAUL), and international bodies such as UNESCO. This has sparked conversation about best practice and expectations from many stakeholders involved, driving change in areas of concern. Such areas include addressing the concerns around ‘double-dipping’ witnessed with hybrid journals. In recent years, the publication of OA books and monographs has also risen, with many of the issues surrounding the cost of publishing open access now being actively addressed by stakeholders in the academic community. Read further to learn more about these concerns, and what initiatives have lead to greater change in OA publishing. Transformative Agreements A subscription or hybrid journal that makes an explicit commitment to moving to fully open status is known as a Transformative Journal (TJ). The publishers of transformative journals have pledged to offer more content openly over time and to resist collecting double payments by offsetting subscription income from payments for APCs. In Australasia, transformative agreements are negotiated on behalf of universities by CAUL. A list of current agreements is available via the CAUL website. A global registry of transformative agreements is being compiled, collaboratively, by ESAC, a community of Library practitioners coordinated by the Max Planck Digital Library. Transformative and Hybrid Journals The 2018 initiative Plan S, supported by cOAlition S, initially a group of European funders but now with worldwide support, is an important open access initiative. Plan S requires that, from 2021, scientific publications that result from research funded by public grants must be made immediately open access in compliant Open Access journals or platforms. A key premise of Plan S is to move away from the hybrid model of publishing. Plan S-compliant transformative journals make an explicit commitment to transition to Open Access and they are held accountable to specific annual transition KPIs. They also commit to explicitly formulated policies to avoid receiving double payments and to be transparent in their finances. Exercise: View the Frequently Asked Questions (FAQs) for Transformative Journals using the below link. Open access books Until recently, there were few options available for publishing open access books. Partly, this was due to the high fixed costs associated with providing editorial support, proof-reading, and type-setting services to book authors. Open access university book publishing There are a number of successful open access book publishers globally. In Australasia, notable open access book publishers include ANU press. UTS ePress and Tuwhera, based at AUT. Challenge me Read and Publish or publish and read Agreements These agreements are negotiated between a publisher and a library or library consortia, to allow for open access publishing. Read and Publish often relates to the library continuing to pay their subscription fee to read a journal (or package of journals from a single publisher) but allows authors to publish open access for no APC. Publish and Read puts the emphasis on the the subscription being for the publishing open access component but allows readers from the subscribing institution to read for free. With both of these options, it is in an attempt to make library subscriptions move away from read only access to open access. This is a very simplified explanation for both and the contract details for any agreement will vary as negotiated. Exercise: Discover whether or not your institution has signed up to any transformative or read and publish agreements. If yes, how are you promoting them to your users? Are the agreements truly transformative? Attributions Content in this chapter has been developed by QUT Library, including content derived from: - Explore FAQs from Open Access Australasia - Five Open Access Tips for 21st century researchers: Tip #2 from the QUT Blog - Apply for APC Support from QUT Intranet (QUT credentials required) - Bosman, J., Frantsvåg, J. E., Kramer, B., Langlais, P-C., & Proudman, V. (2021). OA Diamond Journals Study. Part 1: Findings. Science Europe & cOAlition S. DOI: 10.5281/zenodo.4558704 All information correct at time of publication, 19 January 2022. Image credits Royalty-free images used on this page were sourced from unsplash.com. Icons created by priyanka, DinosoftLab and Wichai Wi from Noun Project. Open Access Benefits Diagram is by Danny Kingsley and Sarah Brown and is available under CC-BY 4.0 licence.	2,167	common-pile/pressbooks_filtered	https://qut.pressbooks.pub/23scholarlycommunicationthings/chapter/open-access-models/	pressbooks	pressbooks-0000.json.gz:30923	https://qut.pressbooks.pub/23scholarlycommunicationthings/chapter/open-access-models/
8IHjR928qHalKszc	Attack of Fortified Places. Including Siege-works, Mining, and Demolitions. Prepared for the use of the Cadets of the United States Military Academy	Produced by Brian Coe, Wayne Hammond and the Online [Transcriber’s Note: Text delimited by equal signs is bold, Text delimited by uderscores is italic. A character preceded by a caret is superscript, multiple characters enclosed in braces and preceded by a caret are likewise, superscript. Text delimited by braces and underscores is subscript.] ATTACK OF FORTIFIED PLACES. INCLUDING SIEGE-WORKS, MINING, AND DEMOLITIONS. PREPARED FOR THE USE OF THE _CADETS OF THE UNITED STATES MILITARY ACADEMY_. BY JAMES MERCUR, _Professor of Civil and Military Engineering at the United States Military Academy, West Point, N. Y._ _FIRST EDITION._ FIRST THOUSAND. NEW YORK JOHN WILEY & SONS, 53 EAST TENTH STREET. 1894. COPYRIGHT, 1894, BY JAMES MERCUR, West Point, N. Y. _Right of Translation Reserved._ PREFACE. In this work an attempt has been made to give in outline the best modern methods of attack upon a fortified position by assault, surprise, blockade, or siege; and also the detailed constructions of those types of trenches, batteries, magazines, etc., etc., which seem best suited to resist the fire of modern cannon, and to afford cover to a besieging force. It is not supposed that these types will be exactly copied in all cases of actual practice, but that a wise discretion will be used in modifying or combining them when necessary or desirable. The constructions given are standard types, which have grown up by combining the suggestions and the experience of the military engineers of all civilized nations. In selecting them I have drawn freely upon the textbooks of the schools of military engineering at Chatham, Fontainebleau, Vienna, and Berlin, as well as upon that of the late Professor Mahan, and the manuals of Duane and Ernst. The standard work of Gumpertz and Lebrun is frequently referred to in “Military Mining”; and I am also under obligations to General H. L. Abbot, Corps of Engineers, for the use of his unpublished notes on the experimental mines at Willett’s Point, and the result of his experiments upon the mining effects of shells charged with different explosives. J. M. WEST POINT, N. Y., October, 1894. INTRODUCTION. Modern wars have been marked by sharp aggressive campaigns and great battles in the open field, with few close and long-continued sieges. The subject of siege-works has therefore attracted less popular attention than was formerly devoted to it. Fort Wagner, Vicksburg, Petersburg, Strasburg, Belfort, Paris, Plevna, and Géok Tépé have shown, however, that at their respective dates regular siege and mining operations were necessary to reduce either permanent or field fortifications, if well equipped and defended. The volume of fire delivered by the small arms and machine guns now in use has made an open assault upon a well-supplied and well-defended parapet, under ordinary circumstances, a hopeless undertaking, and has necessitated more deliberate methods of attack. The increased accuracy and penetration of modern cannon have rendered obsolete many of the older methods of making regular approaches. The newer constructions described herein, while giving greater protection to the attack, are in general slower in their advance than those previously used. This seems, however, to be an unavoidable evil, which is mitigated only by taking advantage of every opportunity for rapid advance offered by the errors of the defence. It is not to be inferred that light field works and lines will in the general case require for their attack a system of regular approaches; but trenches and saps may be necessary for placing a battery or parapet in a commanding position or one favorable for enfilade, or for giving a covered approach over an exposed ridge; and their frequent employment may be expected on future fields. The destructive effect of grenades and Coehorn shells charged with high explosives will doubtless in many cases check or stop the advance of saps and trenches, and necessitate the use of blinded approaches or mining-galleries in stubbornly contested sieges. The successful application of mines at Géok Tépé will doubtless lead to their future employment under similar circumstances. In the close attack upon a shielded casemate or disappearing turret their use seems a necessity, and when these defences are founded on rock or massive concrete foundations, tunnelling operations by drilling and blasting will be required. When practicable they will be expedited by the use of power-drills driven by electricity. It seems hardly necessary to add, that in sapping and mining operations, as in all other branches of military engineering, all new and improved inventions and methods which are applicable to the work on hand will be used, as a matter of course. The thickness of cover given in the text is based upon the penetrations of the hostile projectiles. For ready reference the maximum penetrations obtained in experimental firing up to this date (1894) are given herewith, viz.: Service bullets, copper or German-silver jacket, of 6.5 to 8 mm. calibre, initial velocity from 2000 to 2550 f. s.: At Muzzle. 100 yds. 900 yds. 2000 yds. 2730 yds. Inches. Inches. Inches. Inches. Inches. Pine wood 30 to 50 31 to 35 10 to 14 4.4 Seasoned oak wood 4 to 8 1.18 Untamped clay 60 to 78 Light sand 8 At 500 yds 17 inches. 330 yds. 440 yds. 880 yds. 2000 yds. Inches. Inches. Inches. Inches. Sand and earth 36 33 20 14 4 Steel and iron plate 0.31 to 0.38 0.28 0.24 Brick masonry 4½ Ice 63 Special steel-coated bullets, cal. 0.26 and 0.30: Pine wood 55 Oak wood, seasoned 16 to 24 Beech wood 23 to 30 Sand 14 Special steel-coated bullets, cal. 0.236, vel. 2600 f. s. Pine wood 62 French authorities give a muzzle penetration of 12 mm. = 0´´.473 in iron plates for the Lebel bullet. No published experiments confirm this. But few experiments seem to have been made to determine the penetration of the projectile of field and siege guns into earth, and the published data are very meagre and unsatisfactory. The German Engineer’s Handbook (Pionier Taschenbuch, 1892) prescribes the following thicknesses of parapets for cover against small-arm and cannon fire, viz.: ----------------------------+------------+------------+------------+------------ \| \|Shrapnel and\| \| Material. \| Small Arm. \| Splinters. \|Field-guns. \|Siege-guns. ----------------------------+------------+------------+------------+------------ Earth, sandy \| 30" \| 20" to 40" \| 16½' \| 23' Turf and marshy earth \| 60" \| \| \| Wood \| 34" to 40" \| \| \| Brick masonry \| 15" \| \| \| Brick masonry, single shot \| \| \| 3' 4" \| Two steel plates each 0.32" \| 0.64" \| \| \| Packed snow \| 6' \| \| 26' \| Sheaves of grain \| 16½' \| \| \| ----------------------------+------------+------------+------------+------------ English authorities report craters of 21 feet length and 8 feet depth blown out from an earth parapet by a single 200-lb. 8-in. howitzer shell. They also state that the projectile of the pneumatic dynamite gun has penetrated 40 feet of earth. Owing to the rapid development of ordnance the current scientific and military periodicals are in general the only source from which the latest results in penetration, etc., can be obtained. CONTENTS. ATTACK OF FORTIFIED PLACES. PAGE INTRODUCTION. v CHAPTER I. THE ATTACK WITHOUT THE USE OF REGULAR APPROACHES. ARTICLE 1. Blockade, 1 2. Surprise, 2 3. Defence against Surprise, 4 4. Assault, 4 5. Dispositions for an Assault, 5 6. Defence against an Assault, 7 7. Bombardment, 8 8. Defence against a Bombardment, 10 CHAPTER II. SIEGE OR ATTACK BY REGULAR APPROACHES, PRELIMINARY CONSTRUCTIONS, DEFINITIONS, ETC. 9. Siege, Progress of, 12 10. Tools and Appliances, 13 CHAPTER III. TRENCHES, APPROACHES, PARALLELS, SAPS, SPLINTER-PROOFS AND PASSAGE OF THE DITCH. 11. Trenches, 15 12. Parallels, 15 13. Approaches, 16 TRACING AND CONSTRUCTING PARALLELS AND APPROACHES. 14. Tracing Parallels, 17 15. Tracing Approaches, 18 16. Posting Working Parties, 18 EXECUTION OF PARALLELS AND APPROACHES. 17. Simple Trench and Flying Sap, 20 18. Construction by Simple Trench, 20 19. Construction by Flying Sap, 22 SPLINTER-PROOF COVER. 20. Splinter-proofs, 23 21. Bomb-proofs, 25 SAPPING. 22. Definitions, etc., 27 23. Full Sap, 28 24. Organization and Duties of Detachment, 28 25. Driving the Sap, 28 26. Breaking out a Sap from a Parallel, 30 27. Circular Place of Arms, 31 28. Shallow Sap, 31 29. Overground Approaches, 31 30. Double Sap, 32 31. Execution of the Double Sap, 32 32. Changing Direction of the Double Sap, 33 33. Breaking out a Double Sap from a Parallel, 33 34. Traversed Sap, 33 35. Traverse by Blinded Sap, 35 36. Crowning the Covered Way, 35 37. Trench Cavalier, 36 38. Former Methods of Sapping, 36 39. Passage of the Ditch, 37 40. A Wet Ditch without Current, 38 41. A Wet Ditch with Current, 40 CHAPTER IV. BATTERIES, OBSERVATORIES, AND MAGAZINES. 42. Batteries Defined, etc., 42 43. General Requirements of Siege-batteries, 42 44. Construction of Batteries for Field-guns, 43 45. Batteries for Siege-guns and Howitzers, Elevated and Sunken,--General Considerations, 44 46. Screens, 45 47. Exposed Sunken Battery, 46 48. Tracing the Battery, 47 49. Constructing the Central Passage and Splinter-proof, 48 50. Constructing the Battery, 49 51. Alternative Construction, 50 52. Splinter-proofs (additional), 50 53. Sunken Battery in a Parallel, 51 54. Battery behind Crest of a Hill, 53 55. Batteries on Sloping Ground, 53 56. Embrasures, 53 57. Observatories, 54 58. Drainage, 55 59. Mortar-batteries, 55 60. Magazines, 57 61. Cover for Magazines, 58 62. Location of Magazines, 58 63. Construction of a Magazine subject to Direct Fire only, 60 64. Manner of Executing the Work, 61 65. Mined Magazines, 61 66. Elevated Magazines, 62 67. Precautions against Dampness, 63 CHAPTER V. SIEGE OPERATIONS. 68. The Attack--Successive Steps, 64 69. The First Period, 65 70. The Investment, 65 71. Bringing Up and Posting the Besieging Force, 67 72. Fortifying the Camps, Parks, etc., 68 73. Distance of the Line of Investment from the Works, 70 74. Strength and Composition of the Besieging Force, 70 75. The Point of Attack, 73 76. First Artillery Position, 75 77. Opening Fire, 76 78. Plan of Attack, 78 79. The First Parallel, 78 80. Opening the Parallel, 80 81. The Second Artillery Position, 81 82. Counter-batteries, 82 83. Enfilading-batteries, 82 84. Breaching-batteries, 83 85. Batteries of Rifled Mortars and of Howitzers for Vertical Fire, 83 86. Opening and Conduct of Fire from Second Artillery Position, 83 87. Musketry Fire, 84 88. The Advance from the First Parallel, 84 89. The Second Parallel, 85 90. The Third Period, 86 91. Capture and Crowning of the Covered Way, 87 92. Breaching the Scarps and Counter-scarps, 88 93. Capture and Crowning of the Breach, 89 94. The Attack by Sap, 91 95. Additional Operations Necessary in the Attack of an Intrenched Camp, 91 96. Occupation of a Conquered Place, 93 97. Vauban’s Maxims, 94 98. Journal of the Attack, 97 CHAPTER VI. THE DEFENCE. 99. Preliminary Considerations, 98 100. Garrison, 99 101. Armament, 100 102. Ammunition, Provisions and Supplies, 101 103. Sanitation and Hygiene, 101 104. Preparations for Defence, 101 105. Defence during the First Period, 103 106. Opening of Artillery Fire by the Defence, 104 107. Defence during the Bombardment and Assault, 105 108. Defence during the Second Period of the Siege, 106 109. Defence during the Third Period of the Siege, 107 110. The Capitulation, 109 111. Journal of the Defence, 110 CHAPTER VII. PARKS, DEPOTS, SHELTERS AND HUTS, KITCHENS, OVENS, SINKS, LATRINES, WATER-SUPPLY, ETC. ARTICLE PAGE 112. Parks and Depots, 111 113. Shelters and Huts, 113 114. Kitchens and Ovens, 114 115. Latrines, Sinks, etc., 115 116. Water-supply, 116 _PART II._ MILITARY MINING. CHAPTER I. NOMENCLATURE AND THEORY. ARTICLE PAGE 1. Definitions, 119 2. Theory of Explosion, 120 3. Form and Volume of Crater, 121 4. Relation between Volume of Crater and Charge, 122 4. Miner’s Rule, 122 5. Charge for One Cubic Yard, 123 6. Rule for Common Mines in Ordinary Earth, 124 7. Overcharged and Undercharged Mines, 125 7. Deduction of Formula for Charge, 125 8. Relation between Charges of Common and Over- or Undercharged Mines, 127 8. Charge to Produce a Camouflet, 128 9. Radius of Rupture, 128 10. Theoretical Value of Radius of Rupture, 129 11. Values Adopted by English Authorities, 131 12. Theoretical Value Too Small, 131 13. High Explosives, 131 14. Experimental Determinations, 131 15. Choice of Explosives, 132 16. Probable Advantage of High Explosives for Overcharged Mines, 133 17. Relative Advantages and Disadvantages of Gunpowder and High Explosives, 134 CHAPTER II. PRACTICAL OPERATIONS AND DETAILS. 18. Tools and Appliances, Description of, 136 GALLERIES AND SHAFTS. 19. Dimensions of Galleries and Shafts, 138 20, 21. Shaft and Gallery Linings, 139 22. Shaft and Gallery Frames, 140 23. Dimensions of Pieces of Frames, etc., 141 24. Relative Advantages of Cases and Frames, 141 25-28. Sinking Shaft by Frames and Sheeting, 141 29. Precautions Needed, 144 30. Partly-lined Shafts, 145 31. Driving a Gallery with Frames and Sheeting, 145 32. Use of False Frame, 146 33. Use of Shield, 147 34. Inclined Galleries, 147 35. Position of Frames, 148 36. Partly-lined Galleries, 148 37-39. Change of Direction of Galleries with Frames and Sheeting, 148 38. Change of Slope, of Galleries, 149 40, 41. Returns, 150 42, 43. Maps and Drawings, 151 44, 45. Sinking a Shaft with Cases, 152 46-48. Driving a Gallery with Cases, 153 49. Change of Direction of Galley Lined with Cases, 154 50, 51. Change of Slope, 7 Galleries Lined with Cases, 155 52. Shafts à la Boule, 156 53-55. Blinded Galleries, 156 56. Rate of Advance of Galleries, 157 VENTILATION OF MINES. 57. Sources of Deleterious Gases, 158 58. Ventilation by Forcing in Air, 159 59. " by Exhausting Air,159 60. " by Assisting Natural Ventilation, 160 61. " by Use of Masks, etc.,160 MINE-CHAMBERS. 62. Form, Size, and Location of Chambers, 160 LOADING AND FIRING MINES. 63. Preparing the Charge, 161 64. Distribution of Fuses in Charge, 161 65. Character and Construction of Fuses, 163 66-68. Electric Fuses, 163 69. Placing the Fuses in the Charge, 164 70. The Fuzes in Frozen Dynamite, 165 71. Placing the Charge, 165 72. Tamping Mines, 166 73. Firing Mines, 166 CAMOUFLETS BY BORING. 74. In Favorable Soil, 167 75. In Stony Soil, 168 CHAPTER III. ORGANIZATION AND TACTICS OF MINES. 76. Organization of Mines, 169 77. The Attack, 169 78. The Lodgment, Galleries, Transverses, Listening-galleries, etc., 170 79. Avoid Exposing a Flank, 171 80. Use Overcharged Mines, 171 81. The Defence, 171 82. Conditions to be Fulfilled, 171 83. System of Galleries Used, 172 84. Use Undercharged Mines, 172 85. Shaft Mines, 172 MINE TACTICS. 86. Tactics Derived from Results of Experience, 172 87. Todleben’s Rules, 173 88. The Attack, 173 89. The Defence, 174 90. Advantage Lies with Besieger, 176 BREACHING BY MINES. 91. Preparation of Wall Location and Size of Charge, 176 92. Galleries behind Counter-scarps, 177 93. Galleries through Scarp, 177 CHAPTER IV. BLASTING AND DEMOLITIONS. 94-97. Definitions; Tools and Appliances, 178 98. Tamping Blasts, 179 99. Determining the Charge, 179 100. Precautions, 180 DEMOLITIONS. 101. Deliberate Demolitions, 180 102. Hasty Demolitions, 181 103. Houses and Magazines, 181 104. Walls, 181 105. Stockades, 182 106. Bridges, 182 107. Tunnels, Canal-locks, etc., 183 108. Railroads, 183 109. Rolling-stock, 184 110. Excess of Explosive to be Used, 184 ATTACK OF FORTIFIED PLACES. CHAPTER I. THE ATTACK WITHOUT THE USE OF REGULAR APPROACHES. =1.= A fortified position may be taken by _blockade_, _surprise_, _assault_, _bombardment_, or _siege_. A =blockade= consists in so surrounding a place and closing its communications as to keep the garrison from receiving reinforcements, provisions, and supplies sufficient to enable it to continue the defence and to avoid starvation. The object of the attacking force is, in general, to completely close all communications between the garrison and the exterior; but this is not always possible, nor is it necessary in all cases, since such obstruction of communications as will reduce the incoming supplies below the necessary expenditures of the garrison will ultimately exhaust its stores. An efficient blockade, continued long enough, will consequently reduce any place. Whether it is advisable to attempt to reduce a place by blockade will depend upon the time which will probably be taken in its reduction, the force required for surrounding it, and repelling sorties from the interior or beating back a relieving army, and the expense in men and materials of taking the work by other methods. Blockades are more effective in reducing cities and towns than in taking places occupied only by a military garrison, since the presence of a large number of non-combatants in a place rapidly exhausts its store of provisions, renders epidemics more likely to break out, and by the suffering and misery resulting demoralizes the garrison, unnerves the commander, and eventually causes its fall. This justifies the apparent harshness of not allowing non-combatants to leave a beleaguered place. The steps necessary for establishing the blockade are identical with those taken for the investment in a regular siege and will be described hereafter. The capture of Paris in 1870-71 is one of the most recent and striking examples of a blockade on a large scale. SURPRISE. =2.= A sudden and unexpected attack made upon a garrison unprepared to receive it is called a =surprise=. Formerly these were of not infrequent occurrence, but with modern means of communication and methods of warfare they can hardly be looked for, except in small affairs, where, through the weakness or exhaustion of a garrison or the incapacity of its commander, the necessary and ordinary precautions for their prevention are impracticable or are neglected; or where they are brought about through treachery in the garrison, by which the gates are opened to the attack. Probably in the majority of cases attempts at surprise will be detected and defeated; but as a success is usually valuable far in excess of the losses suffered in its execution, promising opportunities for their trial should not be neglected. Surprises, when thought possible, are undertaken under the cover of night, fog, or severe storms. The tactical disposition of the troops is similar to that used in open assault, the columns being preceded by ladder-parties for scaling walls, engineers for blowing down barriers, etc., etc., according to the nature of the case, and followed by a large reserve which is designed to hold any points captured by the advancing columns. It is usually considered best to make simultaneous attacks at several points, in order to confuse and divide the defence, holding the main reserve nearest to the column which is expected to succeed; but making provision also for promptly and fully supporting any other party which may have forced an entrance into the work. An entrance secured, consecutive points should be occupied and held, preserving communication between them, and avoiding too great dispersion of the troops, until a foothold is gained which can in all probability be held against the defence. After this greater boldness may be used in attacking important points within the place. The complete capture of the work and its garrison cannot ordinarily be expected, however, until daylight allows the systematic movement of the attack throughout the place. In case of failure, any captured gate must be held if possible until all the troops have retreated through it and are covered by the reserves. DEFENCE AGAINST SURPRISE. =3.= The measures necessary to guard a fortified place against surprise are of two classes. First, for its prevention, by use of all the usual outposts and interior guards,--the organization and duties of which need not be repeated here,--and of telegraphic and other signals and communications with the surrounding country by which the approach and movements of any attacking force may be made known before it comes near the work. Second, for its repulse, by so training and disciplining the garrison that, upon the alarm being given, the parapets, batteries, etc., will be manned and all defensive measures will be taken before the assaulting body can enter the work. This will be accomplished by so thoroughly drilling the garrison in its duties that each man will go at once to his proper station fully equipped for his duties at any hour day or night, without confusion or unnecessary excitement. The subsequent measures are the same as for resisting any other assault. ASSAULT. =4.= By an =assault= is meant an open attack upon a position by troops in line or column. Formerly it was recommended to make assaults at early dawn, in order to have the increasing daylight for securing the results of victory; more recently night attacks have been more strongly advocated in order to diminish the losses from the fire of the defence while making the attack, and the still greater ones which follow a repulse when, the fire of the supports and reserves of the attack being suspended for fear of injuring the retreating troops, the defence pours upon the latter the full close and deadly fire of all its arms. Whether the advantages of a night attack more than counterbalance the dangers resulting from the confusion due to darkness is, however, a question not yet settled. Open assaults upon fortified positions, well manned and armed, have, since the introduction of firearms, been considered the most bloody, uncertain, and frequently the most unjustifiable operations in war. With the introduction of machine and rapid-fire guns and magazine rifles it may be considered as an established fact that a well-defended line cannot be carried by an assault in front until its fire is overpowered or its ammunition exhausted. This conclusion, which has been drawn from attacks on field-works, is still more positive in regard to attack upon works of strong profile protected by deep ditches and other obstacles. DISPOSITIONS FOR AN ASSAULT. =5.= When an assault is ordered the tactical dispositions must be so made as to keep the fire of the defence down to its lowest possible limit, until the assailant can close in with the bayonet. With this end in view, batteries are established sweeping the lines; the assaulting columns, well supplied with ammunition, are formed where protected from fire; working parties are arranged and provided with such tools and appliances as are necessary for removing or overcoming obstacles; and all preparations are made for simultaneous action by the entire force. It is manifest that to silence the fire of the work the attack must have a marked preponderance of artillery arranged both for enfilade and front fire upon the front of attack and the collateral works; and that the batteries must be established, the fire opened, and the guns of the defence silenced before the assault is made; and that this fire must continue until the assaulting troops are so near the work as to necessitate its discontinuance to avoid injury to them. The working parties--carrying axes, saws, crowbars, and similar tools which are needed for removing the existing obstacles; explosives for blowing down gates, barriers, etc.; fascines, gabions, hurdles, etc., for crossing ditches, covering trous de loup, and other purposes; and, when necessary, ladders for escalade--move forward with the columns of attack; the latter must be so handled that, when the artillery fire is suspended, they can keep down the fire of the defence with rifle and light machine-gun fire. Under cover of this fire the obstacles must be removed by the working parties, and the first assault made by the troops detailed for this purpose. With these troops should be a certain number of artillerists provided with lanyards, friction primers, etc., to serve any guns that may be captured, turning them against the defence. A party of engineers provided with high explosives for blowing down gates, etc., should follow closely behind the advance in case of an escalade; they should also be provided with appliances for blowing up magazines, etc., when possible, in case of a repulse. The gates being captured and opened, the mass of the assaulting troops enter by them and complete the capture of the place. In case of repulse the retreat of the advanced parties is covered, when possible, by the infantry fire of the reserves, and that of the latter by the artillery, as in the advance. DEFENCE AGAINST AN ASSAULT. =6.= Permanent works being designed to be secure against assaults and surprise, their guns of position are protected as well as circumstances admit against the hostile artillery and infantry fire. During the cannonade preliminary to an assault a wise discretion must be used as to how much ammunition may be profitably expended in replying to it, and how great an exposure of the men to the artillery fire is justifiable. As a rule but little reply is made from the work. The machine and rapid-fire guns should be withdrawn from the parapets and be protected under bomb-proofs until the relaxation of the hostile fire due to the near approach of the assault allows them to be run out and to open fire. The infantry of the garrison is similarly handled, being held under cover until the proper moment, then manning the parapet and pouring a close, rapid, and deadly fire upon the assault. The fire of the fronts directly attacked, both machine-gun and infantry, will be directed principally at the assaulting columns and working parties, the collateral works and fronts will, in addition to pouring a cross-fire upon the assaulting columns, direct a large part of their machine-gun fire upon the supports and reserves, while the more powerful guns will generally direct their fire upon the hostile artillery. The troops not needed for manning the parapets are held under cover in a central position as a reserve, to strengthen the force at any part of the parapet or to meet and drive out any body of the enemy penetrating the work. Should the attack be repulsed, the most rapid and destructive fire from all arms is directed upon the retreating troops with a view to inflicting the greatest possible losses; but a counter-attack is, as a rule, not attempted. When made, however, it should be limited to making an advance upon one or both flanks to a position giving a more effective fire upon the retreating troops, and retiring from this position to the cover of the work as soon as the main attack is completely repulsed and before the advanced troops become compromised by a close engagement with the enemy. BOMBARDMENT. =7.= By a =bombardment=, technically speaking, is meant a more or less continuous shell-fire upon a place with a view to destroying magazines, buildings, materials, and supplies of all kinds, in addition to inflicting the greatest possible losses upon the garrison and producing among the inhabitants a state of terror and unrest, frequently extending to mutiny, and finally causing the surrender of the place. The term bombardment is also frequently applied to a cannonade opened upon a place to silence its artillery prior to an assault or during a siege. A bombardment promises success when the place is small and not well provided with bomb-proofs, when the garrison is weak or of bad morale, when the inhabitants are numerous and not in sympathy with the garrison, or when the commandant is weak. A well-built and well-equipped modern fort can hardly be reduced by bombardment with any reasonable expenditure of time and ammunition; although the successful use of torpedo-shells charged with high explosives will probably render untenable works not designed to resist their effects. When it is designed to reduce a place by bombardment a complete investment is, as a rule, necessary only to prevent the withdrawal of the non-combatants (a severe measure, but one frequently adopted), or to insure the capture of the garrison upon the fall of the place. The disposition of the troops is made for the special object in view. The infantry, cavalry, and field artillery complete the investment, if made; or, when the place is not invested, are concentrated at such points as may be necessary to protect the artillery from any sorties from the place, and to meet and repel attacks from any relieving force. The artillery of larger calibre used for the bombardment proper should consist principally of rifled howitzers and mortars, which are easier to transport and more suitable for high-angle fire. As it is not intended to dismount or silence the guns of the place by direct or enfilade fire, an artillery duel should be avoided. The batteries should be located, so far as possible, in places screened from the artillery of the defence by undulations of the ground, etc.; or, if this is impossible, by artificial screens as a cover from sight, and by trenches as a protection from fire. Considerable latitude is allowed in selecting sites for batteries. For convenience of supply and unity of command they should be collected in groups, the batteries of the groups separated by at least 100 to 200 yards; and the groups should be located, so far as other considerations allow, near the main lines of communication. If these groups do not entirely surround the place, they should, when practicable, extend at least half way around, so as to bring a reverse fire on all covers. The fire, once opened, should continue night and day. If a conflagration breaks out, a sharp fire of shells should be directed upon it and its vicinity to prevent its extinction. Special efforts should be made to blow up magazines and destroy shops, storehouses, docks, roads, bridges, or other communications useful to the defence; but, so far as is practicable consistently with these, an attempt should be made to avoid injury to public monuments, museums, antiquities, and works of art. Bombardments are sometimes commenced and continued for a longer or shorter time without the expectation of reducing the place, but to destroy some of the constructions above mentioned or to prevent the completion or arming of a work which it is intended to attack by other methods. A slow bombardment may also precede the active cannonade which prepares for an assault, or the systematic artillery attack of a regular siege. DEFENCE AGAINST BOMBARDMENT. =8.= The defence against bombardment is frequently, from necessity, strictly passive, and consists in so disposing the troops and materials as to protect them under bomb- and splinter-proofs, repairing damages to the latter and to magazines and parapets as occasion offers; saving the ammunition of the place by firing only such shots as promise to pay for themselves by the effect produced; and reserving all the strength of the place to meet the subsequent attack, if made. When circumstances admit, a more active defence may be made, by a strong garrison, by well-conducted sorties which may capture and destroy the hostile guns and batteries and defeat and drive off their supports. Sorties of this kind may sometimes be profitably made against the flanks of the attacking force, or against isolated batteries, even when a general attack cannot be made. Opportunities for their use should not be neglected. CHAPTER II. SIEGE OR ATTACK BY REGULAR APPROACHES. PRELIMINARY CONSIDERATIONS, DEFINITIONS, ETC. =9.= By a regular siege is meant a systematic and more or less deliberate attack upon a fortified place, in which the besieger aims to invest the place and capture its fortifications in succession by regular approaches, beginning with the most advanced and ending only with the reduction of the innermost keep and the surrender of the garrison. The successive steps of a siege are usually the following: The investment. The artillery attack. The construction of parallels and approaches. Breaching by artillery or mines. The final assault. The introduction of modern breech-loading rifled guns, howitzers and mortars, rapid-fire and machine guns, and magazine small arms has brought with it the need of a higher grade of mechanical skill and improved machinery for making the ordinary repairs. This imposes upon both attack and defence the necessity for providing machine shops and tools fitted for work of this kind, with the steam power required to drive them. In connection with these, steam sawmills and other simple wood-working machines should be provided, as well as all other available labor-saving appliances which can be used to lighten the labor of the troops. Portable tools, such as picks, shovels, crowbars, rammers, axes, hatchets, bill-hooks, gabion-knives, hammers, saws, carpenters', joiners' and blacksmiths' tools, etc., etc., must be provided. =10.= The principal =special tools and appliances= used are the following, viz.: sap-forks, sand-bag forks, scrapers, sap-shields, measuring-rods of various lengths, pocket compasses with attachments for fastening them to measuring-rods, tracing-lanterns, dark and ordinary lanterns, tracing tape or cord, tracing pickets or stakes, fascines, gabions, hurdles, sand-bags, blindage and gallery frames and sheeting, etc., etc. The _sap-fork_ and _sand-bag fork_ (Pl. I, Figs. 1 and 2), about 4½ and 4 feet long, respectively, have steel heads with three and four prongs, as shown in the figures, those of the sap-fork being sharp and those of the sand-bag fork blunt. They are used for handling and placing gabions, fascines, and sand-bags in position when, without their use, the sappers' arms would be exposed to fire. The _scraper_ (Pl. I, Fig. 3) is a large hoe, of about the dimensions given in the figure, used for levelling off the surface of parapets, etc. The _sap-shield_, introduced by the English (Pl. I, Figs. 4 and 6), is a flat plate of mild steel 3 feet 6 inches by 1 foot 9 inches × ¼ inch, with two handles on its back as shown. Total weight, about 80 lbs. It may be used as shown in the figure, and sometimes by small parties as a body-shield in such operations as blowing in gates, etc., etc. _Measuring-rods_ of rectangular cross-section, straight and divided into feet and inches, are needed for special purposes; but the ordinary rods are cut from round brush wood and to the length required. _Tracing-tape_ is usually a white tape, about 1½ inches wide, in lengths of 150 feet, marked at equal intervals, usually 5 feet, by short pieces of tape sewed to it. A loop of strong cord is fastened to each end. For convenience in use it is ordinarily rolled into a ball. _Tracing-pickets_ are about 18 inches long and one inch in diameter. To make them visible in a dim light the bark is removed from them. _Ordinary pickets_ are usually 3½ or 4 feet long, 1½ to 1¾ inches in diameter, sharpened to a triangular point. The _tracing-lantern_ (Pl. I, Fig. 5) is a dark lantern with a reflector arranged to throw a light vertically downward. The other tools, materials, and appliances above mentioned, not of the ordinary commercial patterns, are described in Field Fortifications and Military Mining, _q.v._ CHAPTER III. TRENCHES, APPROACHES, PARALLELS, SAPS, SPLINTER PROOFS, AND PASSAGE OF THE DITCH. =11.= =Trenches.=--A _military trench_ consists of a ditch and embankment affording cover from direct fire. Trenches are used for _approaches_ (or _boyaux_), _parallels_, and _communications_ with magazines, etc. =12.= =Parallels= are trenches which take their name from the fact that they usually are located on lines approximately parallel to the general front of attack. In a regular siege at least three and frequently a greater number of parallels are used. The exterior one, which is first made, is known as the _first parallel_, the next one as the _second parallel_, and so on. They are used to cover the part of the besieging force known as “_the guard of the trenches_,” which protects the men making the approaches, etc., and also as “places of arms” for assembling troops for assault or for other purposes. The trench of a parallel is usually 10 feet wide at the bottom and 4 feet deep, finished on the reverse with a slope and on the front with two steps and a berm, with treads of 18 inches and rises of 15-18 inches (Pl. I, Figs. 7 to 13). The parapet of the parallel should not be higher than 4 feet 6 inches. Its upper surface, particularly in the second and third parallels, should be made approximately plain with a scraper, and its interior slope should be finished and if necessary revetted, so as to afford a good infantry-fire. To allow the troops to move out to the front in line, portions of the interior slope should be cut into steps of not more than about 18 inches rise, and be revetted with fascines or other materials (Pl. I, Figs. 12 and 13). These portions should be 25 or more yards long and near the approaches. If a general assault is to be made, the parallels must be similarly arranged for the necessary length of front. =13.= =Approaches= are trenches leading up toward the fortification on the front of attack; they connect the parallels and give protection to the besiegers in moving back and forth. To avoid enfilading fire they usually run in zigzags (Pl. VIII, Figs. 80 and 81) across the capitals of the work, with branches seldom exceeding 100 yards in length at the first parallel, and growing continually shorter as they approach the work. Each branch is so directed that its prolongation will pass from 30 to 40 yards outside the most advanced position within effective range held by the defence. At each turning-point of the zigzag the more advanced branch is prolonged from 10 to 20 or more yards to the rear, to cover the angle of the approach. These returns are also useful for storing trench material, etc. After the return is completed the sharp angle in the trench is rounded off to allow gun-carriages, etc., to make the turn. Approaches are usually 4 feet deep, 9 to 12 feet wide at bottom, with slopes in front and rear as steep as the earth will stand, and have a rough parapet not less than 4½ feet high, separated from the trench by a berm of 18 inches, or more if necessary (Pl. VIII, Fig. 82). When drainage requires it, as it very frequently does, the bottom of the trench is sloped from front to rear about 6 inches; a ditch cut along the reverse slope, discharging into the drainage ditches of the vicinity, or into drainage pits excavated in rear of and outside the approaches. These may be lined with a gabion to prevent their sides falling in. TRACING AND CONSTRUCTING PARALLELS AND APPROACHES. =14.= =Tracing Parallels.=--Parallels are located by engineer officers after careful reconnoissance of the ground. Guiding points and lines are marked so as to be readily found in the dusk, but so that they cannot be seen by the defence. When completely screened from view important points are marked by posting sappers at them. When no other practicable method can be used, the directions are determined by the use of a pocket compass fastened to a straight measuring-rod. Tracing is begun as soon as the approaching darkness will conceal the parties from the defence, while close objects are still visible. The length of parallel traced by each officer should not exceed that occupied by one unit, usually a battalion, as a working party. (A battalion of 500 men will occupy 800 yards). The tracing party consists of one officer, one N. C. officer, and one sapper to each 50 yards of parallel, with one or two extra men. The officer is provided with a pocket compass and measuring-rod. The N. C. officer has a tracing-lantern and a mallet with muffled head. Each sapper carries a roll of tracing-tape, a tracing-picket, and a six-foot measuring-rod. The officer stations the first sapper at the initial point, and, taking one end of his tracing-tape, moves along the line of the parallel, accompanied by the rest of the sappers; the first sapper places his picket between his feet, and the N. C. officer drives it into the ground far enough to make it secure. The sapper drops the ball of tape on the ground and lets it run out through his hands until nearly out, when he checks it, and when it is all out places the loop over his picket and lies down to await the arrival of the working party. The N. C. officer, as soon as he has driven the first picket, follows on to the second, etc. The officer, having run out the tape of the first sapper, halts the second, takes the end of his tape, and proceeds as before until the parallel is traced, and a sapper is left at each 50 yards of its length. Each sapper is told the designation, by number and section, of the point he occupies. =15.= =Tracing Approaches.=--The approaches are traced in the same manner as the parallels, but at each turning point of the zigzags a picket is driven, around which the tape is carried. After tracing the branch in front, the tape is cut at five yards in rear of the picket, and the end carried out to the rear in prolongation of the branch in front to indicate “the return,” which is then prolonged to the proper length (from 10 to 20 yards) by a short piece of tracing-tape. POSTING THE WORKING PARTIES. =16.= The working parties are commanded by their own officers, under the guidance of the engineers. They carry their arms and ammunition. Each battalion (or other unit) is marched in column to the depots, where the tools are laid out in lines, so that each man can take up his pick and shovel when drawn up in front of them. But when time does not allow of this arrangement, they are piled, the picks in one pile, the shovels in another, and the men pass the piles in single file to the right of the picks and the left of the shovels, each man receiving a pick and shovel as he passes the pile. If gabions are to be carried, they are distributed in a similar way. When two are carried, the shovel is secured inside one and the pick inside the other, and the gabions are then carried by the picket inserted for that purpose. When one only is carried, the pick is usually secured inside it, the gabion carried on the shoulder, and the shovel in the hand. The working party, in column, provided with its tools, etc., is then led by the engineer officer to the parallel, and forms on right (or left) into line along it in single rank at five-foot intervals, beginning at the initial point of each section. The N. C. officer of engineers assists in this formation, and each sapper points out to the men of the working party the five-foot intervals marked upon the tracing-tape of his 50 yards, verifies their positions along it, and subsequently superintends their work. Each man when properly placed drives his pick into the ground at the left of his task, places his shovel beside it, and lies down until the command “Commence work” is given. When gabions are used the working party is posted in a manner entirely similar, except that the column is of necessity formed in single rank when marching to the initial point. The men form on right (or left) into line and place their gabions in front of the tape and touching each other; each man then takes out his tools, places them behind the gabions, lies down, and awaits the command to commence work. The sapper sees that the gabions of his 50 yards are properly aligned and touch each other throughout. Both the sappers and working parties are divided into reliefs, usually of eight hours. The sappers of the tracing parties superintend the work of the first relief of the working party, but are relieved long enough before them (½ hour to 1 hour) for the second relief to become acquainted with the details of its sections before the second relief of the working party arrives. A similar arrangement is made for the third relief. EXECUTION OF PARALLELS AND APPROACHES. =17.= =Simple Trench.=--A trench made by excavating the earth and forming a parapet without revetment of any kind is known as a “_simple trench_,” or as “_simple trench-work_.” _Flying sap_ or _flying trench-work_.--When, in order to obtain cover more quickly, gabions are used to hold the earth first excavated, and subsequently to serve as a revetment to the interior slope of the parapet, the trench is known as a “_flying sap_” or “_flying trench-work_.” =18.= =Construction by Simple Trench.=--The first parallel and the distant approaches are usually constructed by the use of the simple trench, as follows, viz. (Pl. I, Figs. 9 and 10): The men having been posted along the tracing-tape at five-foot intervals, as previously described, and their positions verified by the engineer officers, the command “Commence work” is given. Each man marks the left and front of his task by a line dug with his pick, and, commencing at the left of his task, at once excavates a trench 3 feet long, 1½ feet deep, and 6½ feet wide, throwing the earth to the front, and making a parapet 1½ feet high, leaving a berm of 1½ feet. Then, commencing at 1½ feet from the front of his trench, he deepens it to 4 feet, making the parapet 3 feet high. When the task of a party is finished each man cleans off his pick and shovel, places them at the rear of the trench, and leaves them there for the use of the second relief. By excavating in this way, partial cover while at work and a defensible parapet are rapidly obtained, and, at the completion of the task, the parapet admits of a strong defence, and affords cover sufficient to allow the first relief to be withdrawn and the second to be posted without exposure. Special care must be taken during the work to make the men face toward the parapet while digging, in order to avoid striking their neighbors with the pick when raising it for a blow. The second relief widens the trench 4 feet; forms a bottom step 18 inches wide with such materials as are available; heightens the parapet to 4½ feet, and throws the rest of the earth to the front to thicken it (Pl. I, Fig. 8). The third relief widens the trench 2½ feet at the bottom and slopes off the reverse as steep as the earth will stand. The earth is used to thicken the parapet, additional shovels and shovellers being provided if found necessary. The approaches (Pl. VIII, Fig. 82) are extended in a similar manner; the tasks of the reliefs are marked on the sections. Variations from these sections are made when rendered necessary by the presence of rock or water in the soil (Pl. I, Fig. 11); when a wider trench is required for a tramway or for free communication; or, in special cases, when a narrower trench will answer the purpose and save work. Should a specially heavy fire make additional cover necessary, it may be obtained by deepening the ditch and thickening the parapet, leaving its crest at the same height. The sections above given have been found best for ordinary cases. =19.= =Construction by Flying Sap.=--The construction of the first parallel having indicated to the defence the front of attack, further operations will usually be subject to a more destructive small-arm and machine-gun fire. This will, as the siege advances, render the losses experienced in constructing a simple trench too extravagant, and a quicker method of obtaining cover must be used. This method is found in the flying sap (Pl. I, Figs. 8 and 13), which is executed as follows, viz.: The men are posted and the gabions placed as previously described. The engineer officer having marked the lines, the order “Commence work” is given. Each man marks with his pick the front and left of his task (which in this case is 4 × 6½ feet, leaving a berm of 1½ feet), and proceeds at once to dig on its left, filling first the left gabion, next the right, and then throwing the earth over and in front of the gabions. Each gabion, when it is half filled, is tipped outward until it has a slope of about 4 on 1. The filling is then completed. As each man of the first relief occupies only 4 feet of front (2 gabions), his task is four-fifths as great as it is in executing the simple trench. The second and third reliefs have the same tasks as in the simple trench. When the first relief finishes its task, every fifth workman (indicated by the sapper of the section) retains his pick and shovel and returns them to the depot when he marches past it. The others leave their tools for the use of the second and third reliefs. In good soil the gabions may be filled in from 7 to 15 minutes. The English sap-shield is designed for use when the fire is so severe that the flying sap with gabions becomes impracticable. Owing to its weight (80 lbs.) a man can carry but one; hence a carrying party equal to the working party assists in placing the shields and then retires. This gives to each workman a task of 3½ × 6½ feet. The shields are placed as shown in Pl. I, Fig. 6; the trench is executed as previously described, the earth being thrown over and beyond the shield. The shields are removed after the task of the first relief is finished. The sap-shield is designed to be used in special cases for covering the head of a full sap (described further on), in which case it is placed as shown on Pl. I, Fig. 4; and also as a body cover for a man moving for a short distance in the face of a heavy fire, as is necessary at times in sapping and mining operations. It has not yet stood the test of service in a siege. SPLINTER-PROOF COVER. =20.= =Splinter-proofs= for the guards of the trenches, for field-hospitals, latrines, etc., should be provided as soon as possible after the parallels are finished. They may be placed in the returns of the approaches, or in rear of the parallels, and be connected with them by trenches. Pl. II, Figs. 14-16, show their construction when in rear of the parallel and revetted with logs, fascines, or sawn lumber. The trench is 9 feet wide by 4½ feet deep. Its front edge should be 25 or 30 feet in rear of the reverse slope of the parallel. This width of trench will allow 2 to 4 men per yard of its length to work advantageously. They should finish it in 8 hours. In digging the trench the earth is thrown out on both sides, leaving a berm of about 1½ feet on each side to allow the woodwork to be properly placed. When this is completed the earth in rear is thrown forward to complete the cover, as shown in the plate. Steps for egress and openings for light and ventilation may be placed at intervals along the rear, and, when desirable, bunks may be built, as shown in the figures. When the splinter-proofs are built in the returns of the approaches, the overhead cover may extend entirely across, steps and openings being provided as in the previous case; or posts and longitudinal beams may be set in the trench to hold up the rear end of the cross-beams, leaving the rear of the splinter-proof open. Portions of this may be closed, if desired, by leaning short posts or fascines against the longitudinal beam and banking earth against them. The splinter-proofs may generally be drained into the parallels or approaches. When this cannot be done drainage-pits must be used. Limited portions of the splinter-proofs may be protected against leakage through the earth cover by first filling over the covering beams with earth, packing it to a smooth surface with a gentle slope, placing upon it raw hides, roofing felt or other waterproof material, and then completing the cover by adding the necessary thickness of earth, giving finally to its top surface a slope to carry off the rain. BOMB-PROOFS. =21.= When, in the close attack of the work, the besiegers are subject to vertical fire from small mortars, better overhead cover must be obtained by bomb-proofs, constructed by deepening the trench, using stronger beams, and a greater thickness of earth. Twelve-inch timbers laid touching each other, with spans of 5 feet and 5 feet of earth cover, have been considered sufficient; but with the improvement of high-angle fire and the use of high-explosive shells greater protection will be needed in the future. Experimental data for fixing the amount is not now available; an approximate thickness of earth cover may be computed as indicated below. The mining effect of dynamite in common earth is something less than twice that of an equal weight of gunpowder. (See Military Mining, Arts. 13 and 14.) An explosive enclosed in a strong case, however, expends a part of the energy due to explosion in rupturing this case. The stronger the explosive the less will be the percentage of the total energy required for breaking the case, and the greater the percentage remaining for performing other work. For this reason equal weights of high explosives and of gunpowder enclosed in strong shells will not produce the same relative effects in forming craters, &c., that they would if contained in paper cases. The effect of the high explosive is relatively much greater when contained in a strong shell. Experiments made at Fort Hamilton, 1890-91, with 8-inch shells loaded with explosive gelatine, showed this explosive to have between 4 and 5 times the effect of gunpowder, while in paper cases the relative effects were as 1.7 to 1.0. (See Report of Board of Ordnance and Fortification, Ex. Doc. No. 12, 52d Congress, 1st Session, January 5th, 1892.) Since the mining effects of the charges contained in shells are, however, less than when packed in thin cases, the thickness of cover determined by the use of the usual mining formulas should err on the side of safety. Knowing the charge contained in shells to be fired against a bomb-proof, and their probable penetration, the formulas given in Arts. 7 to 12, Military Mining, may be used for finding equivalent common mines and radii of rupture for dynamite and explosive gelatine by substituting in them 1/17 for 1/10. The values given in Art. 11 will probably be sufficiently accurate for the radii of rupture. The cover given in the direction of the fire must be greater than the sum of the penetration and the radius of rupture. When the penetration is equal to or greater than twice the L. L. R. of an equivalent common mine a camouflet will probably be formed, whose radius of rupture, from the formulas, will be equal in all directions and may be assumed as ⅕ of the L. L. R. of the equivalent common mine. In this connection, see par. 61, p. 58. SAPPING. =22.= When the trenches have been carried so near the work that the simple or flying trench cannot be used without undue loss, recourse must be had to the _sap_. A =sap= is a narrow trench (subsequently widened), which is continually prolonged in the desired direction by digging away the earth at its head and throwing it to the front and exposed flank as a cover for the working party. When the sap is subject to an oblique front-fire, exposing one flank only, the parapet is constructed on that flank and at the head. This is known as a _single_ or _full sap_. When both flanks and the head of the sap are exposed to fire two full saps are driven parallel and very near to each other, each with its parapet on the outer flank. The tongue of earth left between them is removed to widen the narrow trenches, thus making a single trench with a parapet on each side. This is called a “_double sap_.” The trench is sometimes deepened and given a splinter-proof roof or cover. This is known as a “_blinded sap_.” A sap gaining ground to the right and front is called a “_right-handed sap_;” its parapet is on its left flank. A “_left-handed sap_” has its parapet on its right flank. To expedite the work in sapping several reliefs should be employed, and task-work should be adopted to induce the men to work rapidly. In all sapping operations the use of the simple trench and flying sap will be resumed when circumstances admit without involving too great losses. =23. The full sap= (Pl. II, Figs. 17-21) requires a detachment, or “=brigade=,” of 1 non-commissioned officer and 8 men, provided with the following tools, viz.: For No. 1, a miner’s pick, a miner’s shovel, a measuring-rod, 4' 6", marked at 3', and a sand-bag fork. No. 2, a measuring-rod of 1' 6" and a shovel. No. 3, a pick, a shovel, and a measuring-rod 5' long, marked at 4' 6". No. 4, a shovel and a scraper with a handle 9' long. For the rest of the detachment, a 6' measuring-rod, knee-caps for 4 men, 2 shovels and 1 pick (in reserve), and, when necessary, a crowbar, axe, and bill-hook. From 100 to 150 sand-bags are supplied to each detachment. =24. Organization and Duties of the Detachment.=--The sappers are numbered 1, 2, 3, and 4 in each rank; the front rank extends the sap 1 yard and is then relieved by the rear rank, and so alternately. The sappers change places at each relief; those who serve as Nos. 1 and 2 during their first task becoming Nos. 3 and 4 during the second, and so on throughout their tour. If a detachment is reduced below 8 in number by casualties it nevertheless keeps 4 men at work driving the sap, and reduces its reserve until new men are supplied. =25. Driving the Sap.=--The sap is driven as follows, viz.: Nos. 1 and 2 dig a ditch 4' 6" deep, 1' 6" wide at bottom, and 3' or more at top; the berm side has a slope of 3/1, and the reverse is vertical, or as nearly so as the earth will stand. They leave no berm, as they need all the cover they can get. Nos. 3 and 4 widen this trench 2 feet and form a berm of 1' 6" by digging away the foot of the parapet and throwing the earth upon its top and exterior slope. The head of their work is kept at 9' in rear of the head of the sap. The side parapet made by Nos. 1 and 2 is about 2' 6" high and bullet-proof (about 2' 6" to 3' thick) at 18 inches above the ground. The head parapet is made up of about 60 sand-bags, from ½ to 2⅔ filled. It joins the side parapet and extends across the head of the sap. It is about 2' 6" high. As the sap is driven forward the head parapet is advanced by throwing the rear sand-bags over to the front by hand or by the use of the sand-bag fork. In excavating the trench No. 1 kneels down, undermines, and digs down enough earth to advance his trench about 9 inches. He is replaced by No. 2, who shovels this earth upon the side parapet toward the head of the sap. No. 1 then resumes his place and throws the sand-bags at the head of the trench over the parapet until he has uncovered about a foot in advance. He uses a sand-bag fork when necessary. The trench is advanced 9 inches more in the same manner. No. 2, besides throwing out the earth dug by No. 1, trims up the slopes and gives the trench its proper width and depth. Nos. 1 and 2 change places when they have advanced the head of the sap 1' 6", and are relieved as before stated when 3 feet is gained. Nos. 3 and 4 work together upon their task. In shovelling the earth upon the parapet they throw it somewhat toward the front and regulate its height with the scraper. The rate of advance is usually from 2 to 4 feet per hour. _Widening the Sap._--The sap is widened by working parties, usually of infantry, who work at about, but not less than, 25 feet in rear of the head of the sap. In an approach their task is equal in volume to that of the sappers, and can be finished in one relief. In a parallel when steps are to be provided, a second relief makes the steps, drainage ditches, drainage pits, etc. _A change of direction_ in a full sap (Pl. II, Fig. 20) is made by No. 1 turning in the new direction and working through the old side parapet; No 2 throwing the earth over the old head parapet. The sand-bags of the old are gradually removed and used for a new head parapet, 20 or 30 additional sand-bags being ready for use if needed before the others can be safely removed. Nos. 3 and 4 follow on as before. A _return_ can be driven back when desired by another detachment of sappers. No head parapet will be needed, but the side parapet will be kept a little in advance of the head of the sap. =26.= =Breaking Out a Sap from a Parallel.=--The head parapet of a sap is about 2' 6" high. The parapet of a parallel is about 4' 6" high. A sap of the usual form driven through the parapet of a parallel will expose the latter to fire through the opening formed. To reduce the danger from this exposure, the sap is broken out at night, and to cover the opening in the shortest time two or three men may creep over the parapet of the parallel and cover themselves by rapidly digging a hole, from which they may work back and join the sappers, who are working outward. The sap being driven obliquely to the front, the trench widened, and the parapet made full size (Pl. II, Fig. 21), the opening will be covered; or a few men may in some cases construct in front of the parallel a short section of flying sap, under cover of which the full sap may be broken out (Pl. III, Fig. 28). Preliminary preparations for breaking out should be made during the day, but should be so conducted as not to indicate the selected point to the enemy. =27.= =Circular places of arms= (Pl. IX, Fig. 83) may be formed in front of a parallel by breaking out two single saps from points 80 to 100 yards apart and so directing them as to meet at 25 or 30 yards in front of the parallel. They may be used by the guards of the trenches or as depots for trench material, etc. =28.= =Shallow Sap.=--When the presence of water in the soil or of rock near the surface prevents driving the full sap 4' 6" deep, a shallow or modified sap (Pl. II, Figs. 22 and 23) may be used, provided a trench 3' deep can be driven forward. In this case Nos. 1 and 2 must both work kneeling, and Nos. 3 and 4 must throw the earth well to the front and keep the parapet as high as possible, leaving the construction of the berm to the widening party, who will give to the trench the necessary width, and will then obtain earth for strengthening the parapet by deepening the trench when practicable and widening it when necessary, making, however, no irregularities which will injure it as a communication and no depressions which will collect water. This sap advances about as rapidly as the full sap. =29.= =Overground Approaches.=--When the water or rock comes to the surface of the ground, approaches can, under favorable circumstances, be driven for short distances by carrying forward earth in sand-bags, forming with them head and side parapets, and moving forward by continually building up the latter and advancing the former as before described. The expenditure of time, labor, and sand-bags is so great in driving approaches in this way that the minimum height of parapet (possibly 5') should be made with sand-bags. This may be subsequently heightened and strengthened with earth brought forward in barrows or hand-carts and thrown upon the top and exterior slope. =30.= =Double Sap.=--(Pl. III, Figs. 24, 25, and 26).--The double sap consists of two parallel single saps driven side by side, the cutting lines of the berms, usually 10 feet apart, making the bottom of the completed trench 7 feet wide. It is used when the zigzags, to avoid enfilade, make such a slow advance as to be no longer profitable, i.e., when the amount gained in advance does not exceed ⅓ the length driven. The double sap is directed toward the work, and is exposed to an enfilading and also to a slant fire from both directions. It must therefore have a parapet in front and on both flanks. =31.= =Execution of the Double Sap.=--The double sap is driven by two detachments, each organized and equipped exactly as for a single sap, except that a greater number of sand-bags should be supplied when practicable. The sappers work as in driving a single sap, with the following modifications only: The Nos. 1 prolong their head parapets until they meet, and in advancing their heads of sap leave undisturbed the 4 feet of head parapet intervening between their trenches, but, by continually throwing sand-bags or earth obliquely to the front, keep the head parapet continuous and nearly straight. This leaves between the trenches made by the Nos. 1 and 2 of the two detachments a tongue of earth 4 feet thick, surmounted with a parapet about 2' or 2' 6" high, which serves as a parados and protects these sappers from reverse fire. Nos. 3 and 4 of both detachments, in completing their tasks, remove this tongue and pass forward the sand-bags forming its parapet for use by Nos. 1 and 2; otherwise the tasks are as in driving a single sap. When sufficient sand-bags are not available the middle part of the head parapet must be made of loose earth, giving much less protection to Nos. 1 and 2. This sap, from its method of construction, is completed by the sappers without the assistance of the infantry working parties. Its rate of advance is about the same as that of the single sap. =32.= =Changing Direction of a Double Sap.=--When a change of direction is to be made No. 1 of the first detachment marks on the berm the width of the top of the trench (10'), Nos. 1 and 2 of the wheeling flank come around the tongue and the leading sappers of the two detachments start their sap-heads in the new direction. Nos. 3 and 4 of both detachments remove the tongue of earth and complete the parapets of the original trench and then follow up their Nos. 1 and 2 as before. =33.= =Breaking Out a Double Sap from a Parallel.=--A double sap is broken out by methods entirely similar to those already described for the single sap (Pl. III, Figs. 27 and 28). The figures explain themselves. =34.= =Traversed Sap.=--A sap may be traversed to protect it against enfilade by frequent changes of direction, generally rectangular (Pl. III, Figs. 29, 30, and 31), or by making hollow traverses by blinding the sap at points separated by limited distances (Pl. III, Figs. 32-35). In traversing a double sap by change of direction, a single sap is broken out to the right or left (or one in each direction) and pushed forward to the desired length. From the flank of this the double sap is again broken out and driven to the front until another traverse is required. When the saps are driven to both right and left a double sap is driven to the front from the extremity of each, and at the next change of direction the single saps are driven towards each other until they meet, and the double sap is driven in the prolongation of its original direction. This forms what is called a _cube traverse_, and gives additional room in the communications. The single sap is used in making traverses, since by throwing all the earth on one side better cover is given. When the sap is so far advanced that it becomes subject to a reverse fire the double sap will have to be used in making the traverses. _Length of Traverses._--Traverses should extend at least 12 feet beyond the trench in their rear, which will give them a length of from 25 to 30 feet on the berm. The salient angles of the sides of the trenches should be rounded as much as practicable to allow the easy passage of guns, and those of the parapets should, when necessary to screen the trench, be held as nearly vertical as practicable by sand-bags. Ramps leading to the surface of the ground may be made in rear of the traverses when needed. For guns they are 8' wide, with slope not greater than 1/4. The work in making traverses being considerable, they should be spaced as far apart as practicable. _Spacing Traverses._--In driving the sap to the front the low head parapet of the sap will defilade a less length in the rear than would the finished parapet of the traverse, which is from 2 to 3 feet higher. The sap is, nevertheless, pushed forward to as great a length as will be defiladed by the traverse when finished, the sappers meanwhile passing the partly protected portion by stooping or creeping when necessary. =35.= =Traverse by Blinded Sap.=--In traversing a sap by blinding a part of its length (Pl. III, Figs. 32-35) the sap is first deepened 2 feet over this part; mine-cases, frames similar to mining-frames, or regular blindage-frames (see Military Mining, Arts. 53-55) are then put in position, the side slopes are held up by sheeting, when necessary, and the top is covered with sheeting, fascines, rails, or other material; earth is then thrown upon the top to bring it up to the desired height for a traverse, which will usually give at least 3 feet of earth covering. When a considerable thickness of earth is to be used the frames must be made correspondingly strong. For a clear opening, 6 feet at bottom, 8 feet at top, and 6' 6" high the English engineers recommend frames at 3-foot intervals, with 6-inch square posts, 2-inch thick sills, and 9 inch × 6 inch caps 12 feet long. The end frames should be braced against outward thrust by 6" × 6" struts. These traverses are usually made at least 20 feet in length. They can be used only when good drainage can be secured. =36.= =Crowning the Covered Way= (Pl. IV., Fig. 36).--The traversed sap is used for “_crowning the covered way_,” which consists in constructing a battery or infantry parapet along the crest of the covered way, from which a fire can be brought upon the ditch and the scarp-wall of the work. To accomplish this the sap is run parallel to the crest, with its nearer cutting line 18 or 20 feet from it. For an infantry trench the traverses may be of the dimensions already given. To cover a battery they should be about 33' long. It will generally be necessary to use the double sap altogether in their construction, but usually the earth excavated by Nos. 3 and 4 of both brigades will be thrown on the parapet next the work, the parapet on the reverse side formed by Nos. 1 and 2 affording sufficient cover for constructing the sap and traverses. The parapet is prepared for infantry fire as described for the parallels. The emplacements for guns, the service magazines, etc., etc., are prepared and the embrasures are cut, or the parapet prepared for the overbank carriages at the last moment, under cover of the small-arm and machine-gun fire from the parallels and places of arms, and the artillery fire from batteries, which do not endanger the working parties. =37.= =Trench Cavalier.=--In order to obtain a greater plunge upon the covered way and ditch, short lengths of double sap are sometimes run at right angles to the direction of the crests of the covered way at about 30 yards outside its salient. The parapet on the side of the sap towards the work is thrown forward and built up to the desired height with gabions and sand-bags, and provided with steps and sand-bag loopholes, giving a short length of parapet with considerable command, firing directly along the covered way at short range. This construction is called a _Trench cavalier_. It will be seldom, if ever, used in the future. =38.= =Former Methods of Sapping.=--Before the general introduction of machine and rapid-fire guns and of small arms of extreme accuracy and penetration saps were constructed by No. 1 sapper driving a trench 18" × 18", which was enlarged successively by Nos. 2, 3, and 4. Cover for the sappers was obtained by the use of a sap-roller (a large gabion, 7' 6" long and 4' in diameter, stuffed with fascines and rods) as a movable head parapet, and the construction of the side parapet was expedited by the use of gabions, sap-fagots, etc. This method cannot be used against an enemy well equipped with modern weapons. It is referred to only as a suggestion that a readily improvised modification of it might be used to capture, with the least possible loss, a party of rioters, criminals, or other badly-armed men occupying an isolated house or other cover. PASSAGE OF THE DITCH. =39.= When breaches which are practicable are made in both counter-scarp and scarp of a dry ditch an assault may sometimes be made successfully; but when the scarp-wall is not breached, or when, for other reasons, an assault from the crowning of the covered way is not considered advisable, the ditch must be crossed and the breach, when made, must be crowned by regular approaches. This is accomplished by the use of a _sap_, _single_ or _double_, depending upon whether it is exposed to fire upon one or both flanks. Owing to the plunging fire of the defence it may be necessary to make the sap deeper than 4' 6", or in some cases to _blind_ it for a part or the whole of its length. It is generally impracticable to drive the sap down the slope of a breach in the counter-scarp; therefore a _blinded descent_ (Military Mining, pars. 53 and 54) is used. It is so directed that when the counter-scarp is reached the floor of the gallery will be at the required depth below the bottom of the ditch; i.e., at the depth fixed for the bottom of the sap. When the small-arm fire of the defence is so severe as to necessitate blinding the sap from the counter-scarp across the ditch, it will usually be imperative to provide a _shield_, under cover of which the sappers may start the blinded sap. This may be made of boards covered with bullet-proof iron-plates, and of such width and length that it may be carried through the gallery, thrust out into the ditch, and then turned, placed in position, and blocked up at such angle and to such height as may be wished, by men who move on their hands and knees and support the shield on their backs. Under cover of this shield the head parapet of the blinded sap may be thrown up and the sap then driven in the usual way. For method of breaching by mines, see Military Mining, pars. 91 and 92. After breaching the scarp, if an assault is to be made, the counter-scarp, for a length equal to or greater than the length of the breach, should be blown down, to give the assaulting party access to the breach. If the breach is to be crowned, and approaches are to be driven against interior retrenchments, a gallery of descent should be driven to the counter-scarp at one side of the breach before the assault is made. From this a trench should be driven to the crowning of the breach (usually by flying sap), by means of which communication is maintained between the crowning of the breach and the exterior. =40.= =A wet ditch without current= may be crossed by building a causeway, upon one or each side of which a parapet is constructed (Pl. IV., Figs. 37, 38, and 41). The floor of the gallery of descent should strike the ditch at about one foot above the level of the water. The counter-scarp wall having been broken through, a shield similar to that described in the preceding paragraph may be used to cover the sappers working at the outlet of the gallery in the first stages of the succeeding work. The causeway is built by throwing into the ditch short fascines or brushwood mats, having bound up with them stones enough to sink them, broken-stone gravel or other available material, until the causeway is 8 or 10 feet long, about one foot above the level of the water and wide enough for the roadway and parapets. The head and side parapets are then constructed with sand-bags, which are passed out under the shield and piled at its head and sides. The causeway is continued by throwing material over the head parapet, and the approach is driven forward somewhat like a sap. So soon as the head and side parapets are made the shield may be raised up and supported upon two or three cross-balks resting upon the side parapets. It may then be progressively moved forward and the approach in its rear be blinded by sappers working under its protection. Unless the plunge of the fire upon the approach is equal to or greater than 45° this shield will, however, when vertical, cover a greater length of trench than when in a horizontal position. It may, therefore, if desired, be turned into a vertical position and be supported by a frame built for that purpose, which can be moved forward as the approach advances (Pl. IV., Fig. 41). When the head of the approach is subjected to the fire of rifle-bullets only, it may be practicable to dispense with the head parapet, replacing it with a bullet-proof screen covering the head of the approach and with wings extending back and overlapping the side parapets (Pl. IV., Fig. 40); the shield floating on a raft of light logs, or other material which cannot be sunk by rifle fire. This shield would, of course, be erected and launched under cover of the one already referred to. To save sand-bags, etc., the interior slope of the side parapets may be revetted with gabions about 4' 6" long, resting on two short fascines and crowned with three others, giving a height of about 6' 3". Upon these, when necessary, cross-beams are laid and the blinding of the approach is finished with sand-bags thrown on top. =41.= =A wet ditch with current=, or one in which the water level may be varied by the defence, presents greater difficulties. The method of crossing which seems most promising is by a causeway made of materials which will allow the water to pass freely through it. For this purpose it is usually recommended to use casks with their heads knocked out, or strong gabions lashed to balks, so as to form continuous tubes, which are loaded with stones and sunk with their axes parallel to the counter-scarp by sappers working under cover of a shield. When the top of the causeway is about a foot above the high-water mark it is levelled off with fascines and the approach driven forward as previously described. When available, iron or terra-cotta pipes of large diameter may, perhaps, be advantageously substituted for casks or gabions. Cormontaigne, at Philipsburg, in 1734, successfully used floating bridges of fascines with parapets of gabions and fascines covered with raw hides. Two bridges were made. They were 128 feet long, 48 feet wide, and 6 feet thick. The water was about 15 feet deep. To construct and hold in place, in a strong or varying current, a floating bridge of sufficient width and depth to support, without sinking or capsizing, the parapets necessary for protection against modern small arms and machine guns is a task presenting such great difficulties that it will hardly be undertaken, except as a last resort, and then with a very uncertain issue. When, however, the fire of the work is nearly or entirely silenced, a floating bridge of pontoons, casks, spars, or other materials, with a slightly masked roadway, may furnish a sufficiently good crossing and may be constructed with little difficulty and loss.[1] CHAPTER IV. BATTERIES, OBSERVATORIES, AND MAGAZINES. =42.= =Batteries= in siege operations are for field-guns, siege-guns, howitzers, and mortars. When the gun-platform is on or above the level of the ground they are known as “_elevated batteries_,” when it is below the surface as “_sunken batteries_.” When they are concealed from the view of the enemy by natural or artificial screens they are called “_screened_” or “_masked batteries_,” and when on sites which can be seen by the enemy “_exposed batteries_.” GENERAL REQUIREMENTS OF SIEGE BATTERIES. =43.= 1st. A good _platform_ for and sufficient space to work each gun. The platform must be suited to the gun used. The space required is about 15 feet front by 20 to 25 feet depth. 2d. A _parapet_ which cannot be penetrated by the projectiles which will be fired against it, and which is high enough to afford cover to the gun and its detachment against curved fire. A thickness of 30 feet of earth will usually be enough for the most exposed batteries. A less thickness may be used when the conditions justify it. The height of the interior crest above the terre-plein should not be less than 7½ feet when this is attainable and may sometimes be greater. 3d. _Traverses._ Each gun is usually separated from the next by a traverse, whose thickness when subject to enfilade fire is the same as that of the parapet (30 feet); under other circumstances the thickness may be reduced if deemed advisable, but should, when practicable, be such that a shell bursting at any point within it will blow out at the top or on one side only. 4th. _Bomb_ and _splinter proofs_ sufficient to cover the gun detachment and reserves against vertical fire. The thickness of cover for these is to be regulated according to the principles laid down in par. 21. 5th. _Magazines_ which will hold at least 24 hours' supply of ammunition, besides recesses near the guns for shells and a few cartridges. 6th. Easy and direct _communications_ for bringing up the guns and placing them in position; including tramways, ramps, etc., etc. 7th. _Look-outs_ or _observatories_ from which the effect of the fire can be seen. These when possible will be placed in high sheltered places well on the flanks of the battery and preferably in advance of it. They may be connected with it by signals, telegraph, or telephone, when necessary. 8th. _Screens._--Earthen screens should when possible be thrown up in front of all exposed batteries. CONSTRUCTION OF BATTERIES. =44.= =Batteries for Field Guns.=--When the place is invested, the field artillery is placed in positions considered most advantageous for repelling attacks from the garrison upon the investing force. _Gun-pits_ (described in “Field Fortifications”) are usually made at once for cover for the guns and their detachments. When any of these sites are occupied during the siege the gun-pits may be connected and converted into a battery as indicated by Pl. IV, Figs. 42-45. A similar construction may sometimes be used during the siege when the artillery fire of the place is weakened, and it is desirable to place a field battery in position for reaching some point in the work. As a rule, however, batteries for field guns will during the siege be constructed in the same way as are those for siege guns and howitzers. =45.= =Batteries for Siege Guns and Howitzers.=--These may be _screened_ or _exposed_, _sunken_, or _elevated_. As a rule each battery has a magazine on each flank. The amount of powder necessary to serve two guns for 24 hours (150 to 200 rounds per gun = 2500 to 6000 lbs.) is as much as it is advisable to have in one magazine, in order to limit so far as possible the disastrous effects of an explosion. For this reason the number of guns in a battery is usually restricted to four. This number may be increased when necessary, or when howitzers firing small charges render it unobjectionable. =Elevated batteries= require much more labor for their construction and for obtaining cover for the men and material than the sunken batteries. They are therefore used only when the target has to be seen and the gun has to be raised for this purpose, or when owing to the presence of rock or water in the soil, or the liability of the site to be flooded it is impracticable to sink the platforms below the surface. As a rule they can be constructed only when covered by a screen either natural or artificial, and then with earth carried in wheelbarrows, sand-bags, etc., etc. =Sunken Batteries.=--When constructed under cover of a screen the depth of the terre-plein of a sunken battery may be limited by the presence of rock or water in the soil, the character of the guns and carriages, and the time available for the work. In a hasty construction the depth of the terre-plein is usually limited to from 3 to 4 feet, which can be dug out in a short time. When more time is available the gun platforms may be put at 5 to 6 feet below the surface and the other parts of the terre-plein may be sunk still lower. This gives but little height of parapet, and the extra earth may be used for giving additional thickness of cover to the splinter-proofs under the traverses and flanks, and also to the magazines. A great variety of plans and profiles may be adopted for batteries of this class, the details of which need not be given, since they will be modifications of those described in Field Fortifications and Permanent Fortifications, and of the exposed battery to be next described. As they are built under cover of screens and are not subject to fire during construction, work upon them may be continuous and by day as well as by night. =46.= =Screens.=--The _natural screens_ used for cover are elevations, woods, hedges, existing buildings, walls, etc., etc. _Artificial screens_ may be made by setting out bushes to imitate hedges or adopting similar devices, which, however, will usually fail to deceive an active enemy. A trench with the earth thrown to the front, forming a glacis-shaped parapet, will, however, generally be effective. It must be made of such length that the enemy cannot know the exact position of the battery, and of such height and thickness that he cannot afford to expend enough ammunition to breach it. This affords not only concealment during construction, but also a remarkably efficient cover to the battery against hostile fire. Screens, natural or artificial, should be from 50 to 100 yards in front of the batteries, so that the enemy’s aim may not be corrected by seeing the points struck by his shells. Unless the screen is of material which will break up into injurious splinters under hostile fire, only enough should be removed before opening fire to unmask the target of each gun, leaving the remainder for concealing the points struck by shells, even if it affords no cover against their penetration. =47.= =Exposed Sunken Battery.=--Before describing the construction of this battery it is necessary to state that upon a site fully exposed to the accurate concentrated fire of a work, directed at night by light balls or electric lights, it will in general be practicable to construct batteries only by sapping, and even then with considerable losses. But these conditions seldom exist, since in the distant attack it is usually possible to construct and arm the battery before it is discovered by the defence, and in the close attack the fire of the defence is generally so much reduced that some exposure is justifiable. While the battery to be described is classed as an “exposed battery,” it is understood that it may also be constructed under cover of a parallel or other trench, and that in all cases when practicable a natural or artificial mask is used to conceal the first night’s work from the enemy. It is assumed from the results obtained in practice that, with the material conveniently stored, the battery can be traced, a central trench and splinter-proof covers be made during the first night, and the battery finished and armed during the second. The general design and details of this battery are due to the Royal (British) Engineers. =48.= =Tracing the Battery.=--The battery is traced under the direction of an engineer officer by one or two tracing parties, each composed as follows: 1 non-commissioned officer with a 6-foot measuring-rod and tracing-lantern, and 4 sappers, one carrying a measuring-tape and bundles of pickets, one a field-level, one several tracing-tapes, and one a mallet or hand-axe; about 75 pickets and 1200 feet of tracing-tape should be provided. The line of fire of the first gun of the battery (_xy_, Pl. V, Fig. 46) is accurately laid out and marked by daylight. At dusk one party drives a picket at _I_, where the directrix crosses the projection of the base of the interior slope, and from this as an origin lays out the cutting lines of the central trench, _I_, _II_, _III_, _IV_, _V_, _I_, making the trench 5 feet wide and of the length required for the number of guns (= No. of guns × 45'--10'); commencing then at a point _A_, 7' 6" to the left of _I_ and in the rear cutting line, this party lays out the line _a_, _b_, _c_, _d_, _e_, etc., ... _m_, _n_, _o_, as indicated, the direction _n_, _o_, leading to the parallel. The second party, beginning at _A_, lays out _A_, _B_, _C_, communicating with the parallel, and then the inner cutting line of the ditch _D_, _E_, _F_, _G_, _H_, _I_, allowing for a thickness of parapet of 30 feet and an ultimate width of ditch of 12 feet (_D_, _E_, and _H_, _I_). Two parties should trace the battery in 25 minutes, one party in 45 minutes. =49.= =Constructing the Central Passage and Splinter Proofs.=--The first relief of working party for the central passage is posted and commences work at once (Pl. V, Figs. 47-48). Each man’s task is 5 feet in length and 4 feet in depth (giving 100 cubic feet). It may be completed in 4 hours, and should be in 6 at most. The second relief (Pl. V, Figs. 49-52) excavates the cartridge recesses, trims up the work done by the first relief, lowers any earth that stands too high, revets the slopes of the gun portions, puts in frames and sheeting when needed in the splinter-proofs, places the bearing planks and balks of the latter, which should be at least 9 inches thick and 9 feet long, except over the cartridge recesses, where they are 12 feet, and when possible deepens the central passage under the splinter-proofs to 5' 6" for a width of 2 feet to form a seat for the men. It also places one or two planks along the passage to serve as a bench for shells. The latter part of this work can be done by daylight. The parapet formed by this excavation is about 2 feet high. This is so masked or so inconspicuous as not to draw upon itself the artillery fire of the defence. The construction of the battery will be continued usually on the following night. =50.= =Construction of the Battery= (Pls. V and VI, Figs. 53, 55, 60, 67).--Two reliefs are required for this. _The first relief_ receives its tools and arrives upon the ground at dusk. It is divided into four parties, one for the front ditch, one for the gun portions, one for the rear trench, and a reserve of ten per cent for substitutes and casualties. They are posted and supervised by the engineer officer, n. c. o^s., and sappers as described in paragraph 16, _ante_. _The Front-ditch Party._--Each digger is assigned a task 5' wide, 6' long, and 3' 6" deep. He throws the earth as far into the parapet as he can. The shovellers, one to each two diggers, are posted 12 feet from the cutting line of the ditch. They pass the earth back toward the interior crest and the traverse, keeping the top surface nearly level. _The gun-portion party_ is divided up equally among the gun portions, each digger is allotted a task 4' wide, 7' 6" long, and 3' 6" deep. The gabions around the gun portion are placed by the shovellers under the direction of the engineer soldiers, a short one being placed at the throat of the embrasure. The shovellers spread and level the earth thrown out by the gun-portion parties and the rear-trench party. They work in connection with the other shovellers to give to the traverses and parapet near the interior crest the proper shape. _The Rear-trench Party._--This party excavates to a width of 7' 6" the rear trench and the communications with the parallel or approach. Each digger has a task 4' wide, 7' 6" long, and 3' 6" deep. The two directly in rear of each gun portion throw the earth to the rear, the others throw it to the front, leaving a berm of 4' 6" at the rear of the traverse. The men of the _reserve_ who are not otherwise occupied fill sand-bags from the earth thrown to the rear, and cut a ramp 8 feet wide and not steeper than 1/4, in rear of each gun-portion, when needed. It is essential that the excavation of the gun-portion be finished by the first relief, so that the platforms may be laid by the second relief in time to allow the guns to be placed before daylight. The first relief leaves in the battery the tools required by the second and carries the rest back to the depot. _The second relief_ is divided into three parties and a strong reserve of one quarter or one fifth of its strength. The first, or _front-ditch party_, works in the front ditch, widening it 6 feet and throwing the earth back to form the front of the parapet. The shovellers, one to each two diggers, spread and level it. The task of a digger is 5' wide, 6' long, and 3' 6" deep. The second, or _platform party_, places the platforms and gives way to the gun detachments. The third, or _rear-trench party_, widens the trench 3' towards the front by cutting off the rear of the traverses. The _reserve_ completes any work left unfinished by the first relief, fills sand-bags and places them around the gun portions, digs ditches and drainage-pits when needed, and does any other work necessary for the completion and arming of the battery. When a tramway is laid in the trench for bringing up the guns and carriages, the ramps in rear need not be cut. =51.= =Alternative Construction in Position Very Much Exposed.=--When the earth thrown up in making the splinter-proofs cannot be concealed, it may attract such a severe fire from the defence as to make the above-described construction impossible. In this case the battery is traced as above described, the balks for covering the splinter-proofs are placed in position resting on bearing-planks, and the construction of the front ditch, gun portions, and rear trench are commenced at once; and the battery is as nearly finished as time allows, and armed if possible. The splinter-proofs are subsequently mined out and the remaining necessary details finished before opening fire. =52.= =Splinter-proofs=, in addition to those in the central trench, are usually constructed under the rear of the traverses (Pl. VI, Figs. 65-67). These may be made during the construction of the battery or after its completion. They are about 5 feet wide, 6 feet deep, and 10 feet shorter than the width of the traverse. Their floor is at 6 feet below the surface. The earth is held up by frames and sheeting, and the roof is supported by cross-balks resting on posts and running back into the traverse. The roof consists of railroad iron or heavy timbers covered with earth, and access is given by steps from the rear trench; the space not occupied by the steps may be shielded with inclined posts or other covering if thought necessary. These splinter-proofs differ in no essential from those described in Field Fortifications. The finished battery is shown in Pl. VI, Figs. 62-64. =53.= =Sunken Battery in a Parallel= (Pl. VII, Figs. 68 and 69).--A battery similar to the one above described is sometimes constructed in a parallel. In this case the traverses have to be built up, and therefore do not usually exceed 20 feet in thickness. Pickets are driven at intervals of 35 feet along the banquette of the parallel to mark the centres of the gun spaces, and the rest of the battery is traced in the usual way. The steps of the parallel are cut away and the slope revetted for the gun spaces and the central trench. Gabions are placed along the back of the central trench and the sides of the traverses. A rear trench 7' 6" wide is cut from the parallel at an easy curve, so that its front cutting-line shall be 25 feet from the foot of the interior slope; this, as before, is widened 3 feet by the second relief cutting away the rear of the traverses. The reverse slope of the parallel in rear of the gun portions is cut back to the rear trench. A trench 2 feet wide and 2 feet deep is cut between the front of the traverses and the foot of the interior slope, and the cartridge recesses are excavated. The gabions of the traverses are filled, balks placed over the central trench, and the tops of the traverses and splinter-proofs are raised to the height of the parapet of the parallel. A ditch in the front of the parallel 12' wide and 3' 6" deep, traced at dusk, and excavated during the night, supplies earth to make the parapet 30' thick and 4' 6" high. The work done in and behind the parallel is not seen from the front, hence a great part of it may be done by day, undetected by the enemy. The upper part of the traverses is made by night, and the front ditch and front of the parapet are made the same night or subsequently, depending upon the number of workmen available. Since the gabions of the traverses seriously obstruct the parallel, they should not be placed in position until all arrangements are made to open the rear trench. In the special case of a battery on the crowning of the covered way, the traverses have been already constructed in running the sap. The splinter-proofs may be constructed by blinding portions of the sap, or by mining them under the traverses. Owing to the height of the parapet, embrasures of some depth will have to be cut through it. This is done by a shallow sap started by one man, who is subsequently assisted by a second, if the splay requires it. The cheeks are revetted with sand-bags, covered with hides. The mouth of the embrasure is left closed with the head parapet of the sap until fire is to be opened, when the earth is dug away or blown away by the gun. =54.= =Battery Behind the Crest of a Hill= (Pl. V., Figs. 57-59).--In a battery behind the crest of a hill the front ditch may be omitted, the gun-portions may be entirely in excavation, and the platforms given such a reference as to require a shallow groove to be cut through the crest to allow the gun to fire. When the ground falls away very rapidly to the rear it may be stepped under the traverses to prevent their sliding, and the rear of the gun emplacement may be raised when necessary to give the platform the proper slope. The central trench is cut deep enough to give 5 feet of cover over the splinter-proofs. =55.= =Batteries on Sloping Ground= (Pl. VII., Figs. 70-72).--When the ground to be occupied by the battery slopes towards or from the place or falls off on either side, the battery is constructed essentially as upon level ground. The central passage is driven, following the surface of the ground, the gun emplacements, front and rear trench are excavated as before described, the additional excavation or filling required in each gun emplacement to make the platform horizontal is regulated for the particular site, any excess of earth being used to give greater cover on the more exposed side, and any deficiency being supplied from the front or rear trench, as may be most convenient. Where the extra work imposed by the slope is considerable, a third relief may be required to finish the battery, and its arming may be necessarily postponed until the next night. =56.= =Embrasures.=--Modern siege guns are generally mounted either on “overbank” or “disappearing” carriages, firing over parapets of sufficient height to give cover to the men. (The axis of the trunnions of the U. S. 5" siege gun is 6" above the platform.) Embrasures when used are generally shallow grooves cut in the top of the parapet. In this case the bottom of these grooves must cut the surface of the top of the parapet at or in rear of the highest line visible to the enemy, so that no indentations which can be seen by him will indicate the position of the guns. To effect this, the exterior crest will usually be as high as and sometimes higher than the interior crest, and the top of the parapet (“superior slope”) will be level or will slope to the rear. In rare instances, however, deeper embrasures with revetted cheeks must be made. The only serviceable revetment for use with high-power guns is one of sand-bags wrapped in raw hides. This may be made by laying down a hide, piling a number of sand-bags upon it, and folding the free end back over them; placing another hide on top of this with more sand-bags and so on. Or large packages may be made by wrapping up a number of sand-bags in each hide and these packages may be used for making the revetment. The embrasure should be bottle-shaped in plan, shaped like a segment of an ellipsoid immediately in front of the muzzle of the gun, then drawn in like the neck of a bottle and narrowed to as small a mouth as possible, so as to diminish the effect of the blast and give the least possible exposure to the gun. When the battery is exposed to slant or enfilading fire, instead of embrasures, bonnets of sand-bags may be built upon the parapets to protect the guns. =57.= =Observatories.=--Observatories or look-outs, as previously stated, should as a rule be placed on high points well on the flanks of the battery.[2] When this is impracticable, they may be made by building up at the rear of the traverses, on the flanks, or even in the gun portions, glacis-shaped covers pierced with a sight-hole in all respects similar to a loop-hole for musketry, and with just sufficient splay to include the desired field of view. A number of these should be provided for each battery, so that the enemy may not know which one is in use at any time. If subject to close and accurate fire, the crest-line in their vicinity must be of the same level as the tops of the look-outs, and provision must be made to prevent the light showing through them. =58.= =Drainage.=--After the completion and arming of the battery, gutters should be cut on each side of the gun-portion leading into one running along the reverse of the rear trench which carries the water to low ground on the exterior, or which is provided with dry wells or drainage-pits for collecting the water so that it may soak into the ground or be pumped out with hand-pumps. =59.= =Mortar Batteries.=--The introduction of rifled mortars of all calibres, with the corresponding increase in accuracy of fire, together with the destructive effects of shells charged with high explosives, will doubtless lead to the extensive use of mortars in future sieges. In a distant attack the requirements of a mortar battery are very simple, consisting principally of a stable platform, magazines for ammunition, and bomb-proof covers for the gunners; since the battery as a rule will be concealed from the view of the work by intervening obstacles, and will in consequence not be subject to direct fire. When the soil is favorable, cover against plunging fire will be most easily obtained by sinking pits for the mortars to such depth as may be necessary to furnish earth for a splinter-proof parapet surrounding the pit, and for cover for the bomb-proof shelters for the men and the magazines. When ample space exists which is well concealed, and in which the soil is good, a separate emplacement should be made for each mortar. When necessary, however, two or more mortars may be placed in each pit. The magazines, splinter and bomb proofs are similar to those elsewhere described. When no natural mask exists, the battery may be constructed behind an artificial screen, and be made of the general type of the “exposed siege battery,” the gun portions being made with front enough to accommodate one or two mortars as may be preferred, and of such length only as is needed for working the mortar employed. The terre-plein may be placed at any convenient depth below the surface of the ground, and the revetment of the interior slope, if any be used, will not ordinarily be carried higher than the muzzle of the mortar. As the traverses are not subject to gun-fire, the splinter-proofs afforded by the central passage may be added to by building others along both sides of the traverse; and by deepening the mortar emplacement sufficiently, they may be given enough cover to make them true bomb-proofs. A mortar battery fulfilling these conditions can hardly be silenced by hostile fire. The conditions under which the batteries may be constructed are, however, so varied that detailed dimensions will not be given. No difficulty will exist in making the battery of a size suitable for the pieces to be employed. The U. S. rifled siege mortar is of 7-inch calibre, about 5 feet long, weighs 1715 lbs., and is designed to throw a 125-lb. shell with a charge of 5½ lbs. of powder, giving an initial velocity of 685 f.s. and a range of about 4000 yards. With reduced charges the range may be reduced to about 650 yards without undue sacrifice of accuracy. In the closer attack upon the work, batteries for the smaller siege and field mortars may be readily constructed in front or rear of the parallels, or in the parallels or approaches themselves; splinter-proofs and temporary magazines being constructed by methods previously indicated. In many cases, however, the lighter mortars, field and Coehorn, which do not require fixed platforms, may be placed behind any part of the trenches affording cover, and fire be opened and continued until the fire of the enemy becomes too annoying, when the mortars may be removed to some other locality. MAGAZINES. =60.= =Magazines= should be provided, at least two to each battery, not only to localize the injury due to an explosion, but also to prevent the battery being disabled by the explosion of a single one. As previously stated (par. 43), they should contain 24 hours' supply (from 150 to 200 rounds) for each gun which they are designed to serve,[3] which may require a capacity in a single magazine of as much as 6,000 lbs. of powder. This amount should be reduced when possible by increasing the number of magazines. The cartridges should be made up and packed in boxes at the depots or parks, and the powder chambers in the magazines should be of such size as to store these boxes with only such vacant space as is necessary for ease in handling them.[4] =61.= =Cover.=--The chamber should be covered with strong balks or rails and enough earth to form a sloping roof; over this raw hides or tarpaulin should be spread, and the remainder of the earth filling be spread upon this and rammed solidly. The amount of earth cover required for security must be determined from the principles given in par. 21. The English engineers recommend as sufficient protection against ordinary fire for a magazine 5 feet wide, two layers of 9" × 9" fir laid crossing each other, or one layer of 12" × 12" oak, covered with 5 feet of earth. In experiments at Lydd in 1883, however, an 8-inch howitzer shell falling at an angle of about 30° penetrated through a covering of 7 feet of soft clay and burst upon the timber roof of a magazine, cutting it through. This shows that complete protection is not always possible, and that the chances of hitting must be reduced by making the horizontal area of the magazine chamber as small as possible, and placing its smaller dimension in the line of the hostile fire. The clear height of the magazine should be 4' 6" to 5' minimum, when practicable, and the top of the covering balks should be at or below the level of the ground. =62.= =Location.=--A magazine should be located at such distance from the battery that its explosion will not disable the guns, injure the parapets or traverses, or seriously endanger the cannoneers;[5] but, on the other hand, it should be near enough to allow the ammunition boxes to be conveniently carried to the cartridge recesses; and the communications for this purpose should be well covered from hostile fire. The entrance to the magazine should be so protected that splinters cannot enter the chamber. Any natural hollows, banks, etc., in the immediate vicinity of the battery should be taken advantage of to facilitate the construction of and give better cover to the magazines. When nothing of this kind exists the magazines may be placed on the flanks or in rear of the battery, and should be masked and screened by the parapet of the parallel, approach, communications, or battery, or by special glacis-shaped screens made, for the purpose; which should be much longer than the width of the magazines that they cover, so that the discovery of the location of the latter by the enemy may be made more difficult. The magazines should not be located in rear of the centre of the screens nor symmetrically with reference to the battery, nor, when it can be avoided, directly in rear of a gun. The passages leading to them should enter the battery in rear of a flank or a traverse, and should be so directed as to escape enfilade. They should be so graded that the surface water will run away from the door of the magazine and be discharged upon lower ground or received in drainage-pits placed at the lowest points. =63.= =Construction of a Magazine Subject to Direct Fire Only= (Pl. VII., Figs. 73-77.)--The method of tracing the magazine and its approaches is too evident to need description. In this example an earth cover of 5 feet against vertical and 20 feet against horizontal fire is given. Should more or less be desired, a corresponding change may be made in the plan, depth of excavation, and depth and width of approaches; and the earth for additional cover may be obtained from a ditch or pit in rear of the magazine. The excavation for the chamber is given a width of 6', a depth of 5' 6", and a length of 12', the entrance a width of 3', a depth of 5' 6", and a length of 6'. The sides of the chamber and entrance are held up by frames 4' 9" high and 2' 11" wide, outside measurement. The caps are 6" × 5", stanchions 4" × 5", and the ground sills 3" × 5"; sheeting 1" thick is inserted between the frames and the earth. The covering balks are 9" × 6" and 10 feet long; their tops are flush with the surface of the ground; cleats nailed on their under side keep the tops of the side frames from being pushed in by the pressure of the earth. The earth cover is 5 feet high at the centre and 4 feet at the crest of the outer slope. The passages are 5' 6" deep, 3' wide at bottom, and 5' at the top. The entrance is blinded by placing balks across the passage for such part of its length as may be thought necessary, and extending the earth covering over them, as shown in the section (Fig. 75). A door, swinging outside, is hung on the outside frame. Heavy railroad iron may be substituted for the timber balks with advantage. When thicker balks are used, or when a second layer is added, the chamber and passage should be correspondingly deepened. =64.= =Manner of Executing the Work.=--The powder chamber and passage are excavated and the frames and balks placed during the first night, while the central passage of the battery is being constructed. The excavated earth is thrown out far enough to allow the balks to be put in position, and is so spread as not to be seen by the defence. This may be done by one relief of 8 hours, or two reliefs of 4 hours each. If the work is not completed during the night, the sheeting, frames, and balks may be placed by day under cover of the earth thrown out and the existing screens. The passages are excavated and the earth cover completed on the second night by two 4-hour reliefs, the first excavating to a depth of 3' 6", and the second to 5' 6", trimming up the slopes and completing the work. When necessary, the sides of the passage will be revetted by the second and a third relief. When the necessity for great haste exists, the excavation of the powder-chamber, entrance, and passages may be carried on at the same time, the excavated earth being thrown in front and on the sides of the powder-chamber until the balks are in position, and then thrown back upon them, levelled and rammed. =65.= =Mined Magazine.=--When the soil, by absence of rock and water, admits of mining, greater cover against vertical fire can be obtained with less work by mining out the powder-chamber and passages (Pl. VIII, Figs. 78, 79). The figures illustrate one of minimum dimensions, which is constructed as follows: The entrance 10' × 5' by 5' 6" deep is first excavated, revetted with frames and sheeting and covered with balks and earth as indicated. At 1 foot from the end a shaft 2' × 5' is sunk to a depth of 12'. From the front of this a gallery 2' × 5' 6" is driven for about 6'; at the end of this galleries 5' 6" × 2' are broken out on each side and driven so far as may be necessary to store the requisite number of ammunition-boxes. (For method of sinking shafts, driving galleries, etc., see Military Mining, Arts. 25, 33, and 44-48.) The excavated earth is spread on top of the magazine to increase the thickness of the cover already given by that excavated from the passages. A ring-bolt is placed in the balk directly over the shaft, for attaching a hoisting tackle for removing the earth during construction and for hoisting and lowering ammunition-boxes afterward. A door opening outward may be hung at the entrance, and the passage may be blinded as previously described, if it is thought necessary. The communications are arranged in essentially the same way as for the magazine previously described. The dimensions given are the least which will allow moderately free access and good cover. The magazine should be constructed, by good miners, in two nights and the intervening day, and will store about 4000 pounds of cartridges in boxes. When time and the character of the ground admit, and larger capacity is desired, the shaft may be made wider and deeper, the gallery wider and longer, and the powder-chamber deeper, longer, and wider, if desired. The excavation for the entrance and approaches, the placing of balks, and the levelling and ramming of the earth-cover, should be done by night; the mining work can be carried on both night and day. =66.= =Elevated Magazines.=--When the presence of rock or water in the soil prevents sinking the magazines to the full depth above given, they must be sunk so far as practicable and given the least possible clear height of powder chamber, with the best attainable overhead cover. This should be strengthened by the use of railroad iron or rolled iron beams, when available. The cover against direct fire should be increased up to 30 feet, and the front slope be made gentle, like a glacis. A screen made of an earthen bank with a glacis slope should also be used if possible. These precautions having been taken, the depth of the powder-chamber in the direction of the hostile fire should be reduced to a minimum, and the storage of large quantities of powder be avoided, so far as possible, by constructing a number of small magazines at the most convenient places in the vicinity of the battery. =67.= =Precautions against Dampness in Magazines for Siege Batteries.=--Underground magazines of the character above described are, of necessity, sometimes damp. The only ventilation usually possible is obtained by leaving the door open, the air being changed more or less by the men going in and out. The passage leading to the powder-chamber should enter it at the middle, and in the service of the guns one half of the chamber should be emptied on one day and the other half on the next. This will usually limit the time which a cartridge is exposed to the dampness of the magazine to a maximum of one or two days. CHAPTER V. SIEGE OPERATIONS. THE ATTACK. =68.= Siege operations include all the steps taken from the first approach to the work up to its final capture. These taken in regular order are as stated in Chapter II: the _investment_, the _distant artillery attack_, the _construction of approaches_ and _parallels_, _breaching by artillery or mines_, and the _final assault_. For convenience in description the siege has been divided into three periods. The _first period_ includes the preliminary operations up to the completion of the investment. The _second period_ includes all the operations between breaking ground for the batteries of the first artillery position and the first parallel, up to the completion of the most advanced parallel and the occupation of a position near the foot of the glacis from which the attack is to be made upon the breach, either by assault or sap. The _third period_ comprises the advance from the last parallel, and all subsequent operations up to the capture of the last entrenchment and the surrender of the garrison. The first and second periods are sometimes known as the “_distant_” and the third period as the “_close attack_.” FIRST PERIOD. =69.= As a preliminary to the siege of any fortified place, all possible information is obtained as to the strength and character of its fortifications, the garrison, armament, stores of provisions and ammunitions, water supply, water routes, telegraph and railroad lines, manufactures, especially those which may be converted into factories of arms and munitions, the character of the population of the place, their probable food supply and their loyalty to their state; also the topographical features and nature of the ground in the vicinity of the work, the sites of camps and parks, the prevalent diseases of the locality and the best means of preventing their attacks, etc., etc. (see Bureau of Intelligence, Art of War, par. 128). From these data the necessary materials and supplies are collected at convenient points, the railroad or water routes selected, and the cars, boats, wagons, etc., for their transportation provided; so that they may arrive promptly and in the proper order when needed. =70.= =The Investment.=--The investing force is brought together, organized, and moved rapidly upon the place. When it is available a large force of mounted troops may be used advantageously in the investment, and be subsequently relieved by infantry and artillery. When the investment is made, it adds greatly to the advantage of the attack to completely surround and isolate the work, and to push the investing line as near it as possible. When the investing force is more or less dispersed, and is to be concentrated for the siege, the temptation frequently exists to march them by converging lines upon the place as a point of concentration. While this may be advisable in some cases (as where the garrison is very weak or under an inefficient commander), it will usually expose the subdivisions of the investing force to be beaten in detail (Art of War, par. 392). So also in surrounding the place; a premature subdivision of the force into small fractions not protected by field-works, or not within supporting distance each other, will afford to an active defence an opportunity, by well-conducted sorties, to inflict most severe losses upon the attack and very greatly delay the investment. Keeping these dangers in view, the investing force will move rapidly upon the work, seize, strengthen, and occupy strong points as near the work as possible, and extend the lines to right and left as rapidly as good judgment allows, until the place is surrounded. Meanwhile detachments of greater or less size will scour the ground around the place, seizing and carrying off or destroying, so far as possible, all cattle, grain, lumber, etc., and everything else which would be of use to the attack or defence. Under cover of these detachments and escorts specially detailed for the purpose, reconnoissances will be made to cover so much of the ground as can be reached, especial efforts being made to examine the ground near the works. These reconnoissances will necessarily be hurried and incomplete but, must be as accurate as they can be made under the circumstances. They should be directed principally to determining the heights and directions of the principal points of the works, and their positions with reference to prominent points that may be used as landmarks, in verifying and correcting maps and information previously obtained, to discovering the existing armament of the place and the steps already taken for its defence, and to collecting all possible information bearing upon the selection of the front of attack. Systematic reconnoissances and surveys carried on throughout the siege must be relied upon for checking and completing the work thus begun. So soon as the supporting points for the investing force are secured, a line of outposts is pushed forward towards the work and sentinels, pickets, etc., are established (Art of War, pars. 167-194). The lines of sentinels, pickets, and supports are placed as near the work as practicable, and the line of resistance is advanced at every favorable opportunity. The usual rules for posting and relieving the outposts, establishing day and night cordons, the use of patrols, etc., are applied, with such modifications as circumstances render advantageous. Any advanced points affording marked advantage to the attack which have been seized are strengthened and held when possible, even at considerable cost in men or with some delay in completing the investment. =71.= =Bringing up and Posting the Besieging Force.=--The main besieging force, consisting principally of infantry, artillery, and engineers, with the siege train, follows closely after the investing force, and, upon arrival is encamped upon sites previously selected, sending out at once, however, such reinforcements and supports as are needed by the line of investment. Engineer and artillery parks are established outside the zone of fire of the works and in proximity to the main routes of communication. Branch railways and tram-roads running through the parks, storehouses, repair shops, etc. etc., are located and constructed. Sites for storage magazines for ammunition are carefully selected at the most secure places, and isolated when possible from the camps and parks by intervening elevations of ground. The cover of these magazines, so far as possible, is made up of wood and sand or earth free from stones large enough to be dangerous projectiles in case of explosion. Rooms for loaded shells and cartridges, and laboratories for making up ammunition are constructed upon similar principles. Carefully studied arrangements for the health and comfort of the men are made. Some of these are outlined in Chapter VII. =72.= =Fortifying the Camps, Parks, etc., etc.=--In former sieges it was customary to completely surround the ground occupied by the besieger with a continuous line of works of simple trace and light profile called the “_line of circumvallation_;” and to construct between the camps and the work another line, either continuous or with intervals, called the “_line of countervallation_.” These lines were placed respectively at about 200 yards in rear and in front of the camps. The principal object of the first was to prevent by a small force the entry of small reinforcing detachments and supplies; that of the second was to resist vigorous sorties by the defence, or sudden attacks from the outside by strong reinforcing parties. For this purpose the detached works of the line of countervallation were so disposed as to cover the main depots, parks, roads, etc., and to be in defensive relations with each other. The great development of the line which must be occupied by the besieger, owing to modern methods of fortification and the range of rifled cannon, prohibits the construction of complete lines of circum- and countervallation. The besieger constructs in their stead one or more lines of detached works upon advantageous points, and covers the intervening ground more or less thoroughly by patrols, outposts, etc. He then so disposes his main force as to be able to concentrate enough to meet any sorties of the defence; and, if necessary, detaches a force, called an “_army of observation_,” sufficiently large to meet any relieving army and defeat it; or hold it in check until he can concentrate the besieging force with the army of observation, and meet the relieving army in a favorable position. As a rule, this position will be one well outside the besieger’s cordon of works; since the latter by its extent will necessarily be weak to resist a determined attack (Art of War, par. 258), and by its proximity to the work will render possible the co-operation of the garrison and the relieving army. This, under the circumstances assumed, would seriously endanger the besieging army. In opposing sorties from the work, however, the conditions which fix the point of conflict are reversed, and place it as near the work as practicable. The shortening and strengthening of the line of investment by closing it in upon the work make it imperative to hold all ground gained; and this is generally best accomplished by intrenching the line of outposts with continuous shelter trenches, strengthened at intervals by batteries of field guns, and supported by field works of considerable strength, placed within accurate cannon range of each other, but not exposed to the direct fire of the guns of the place. Behind the shelter trenches the outposts, supports, and reserves, strengthened when necessary by troops from other points of the line, should be able to hold their own against all ordinary sorties. The main line of field works serves to resist a general attack made by the mass of the garrison. Placing the first intrenchments further back exposes the outposts to the confusion resulting from falling back, frequently at night or in a fog, and also enables the besieged to seize upon ground from which it may be very difficult to dislodge them. To allow the different parts of the line to be rapidly reinforced, good roads protected from the fire of the work, and well marked with sign-posts, etc., must be opened between the adjacent divisions of the besieging force, and all streams must be provided with bridges secure against floods, ice, etc. =73.= =Distance of the Line of Investment from the Work.=--This will result from conflicting conditions. Reasons already given, which need not be repeated, lead to establishing it as near as practicable. On the other hand, the accurate fire of the heavy guns of the place, and vigorous sorties by the defence, cause much annoyance and great loss to a line drawn too near the work. The more recent sieges indicate about 3000 yards from the most advanced works, as the least distance for the line of investment in open country and with an active defence. It may be necessary in some cases to increase this to 4500 or 5000 yards; but with ground favorable to the attack, and a weak and demoralized defence, it may frequently be drawn nearer. =74.= =Strength and Composition of the Besieging Force.=--In former sieges when the place held out until the inner keep was breached and carried by the regular progress of the siege, the ratio of the necessary strength of the attack to the defence was estimated at 7 or 8 to 1, this large ratio resulting from the excessive labor in the trenches and the losses incurred on the close attack. Modern writers (arguing largely upon theoretical considerations) have reduced this estimate to 4 or 5 to 1. No attack on a thoroughly-equipped and well-defended strong place having been carried through all the steps of a regular siege since the introduction of modern arms, absolute data upon this subject are lacking. The besieging force at Strasburg was about 60,000, garrison about 20,000, total length of siege 49 days. The defence was very weak. Belfort, besieging force about 32,000, garrison about 16,000. After a siege of 100 days the approaches were at about 1200 yards from the works, which capitulated by reason of the general surrender of the French. At Metz the besieging force was 150,000 men; the garrison, demoralized by the previous defeat at Gravelotte, surrendered 173,000 men. At Paris the investing force was about 180,000, and the garrison nominally between 300,000 and 400,000, of which perhaps 30,000 were disciplined and effective soldiers; the remainder being made up of remnants of defeated regiments and bodies of the Garde Mobile and Garde Nationale. The investment of Paris was complete on September 19, 1870; its surrender from exhaustion of provisions took place January 29, 1871. Several sorties were made, but the general defence was paralyzed by the character of the troops and inhabitants. At Plevna the Turks had at the outset about 56,000 men, at the surrender 40,000. The Russian force suffered great losses in its assaults, but by continual reinforcement had at the end of the siege about 120,000 men. The defence by the Turks was desperate, but generally passive. One determined sortie was made immediately before the surrender. The surrender resulted from exhaustion of ammunition and provisions. The works were field works only. At Belfort the investing force was at first but 10,000 and the line of investment 25 miles long, giving but 400 men to the mile. This force was subsequently increased to 20,000 men, and when the besieging army had all arrived, to 32,000 men. At Paris (1870) the line of investment was about 3 miles from the line of the forts, and about 53 miles in length, the investing force 180,000, giving a mean of about 2 men to the yard. The distribution was, however, about 4 to the yard on the left bank and 1⅓ on the right bank of the Seine. At Plevna the line of investment was 2¾ miles from the forts, its length 43½ miles, the investing force 100,000 men, about 1¼ men to the yard. In each of these sieges the place finally fell under the attack of a force, in no case equal to 2½ times the garrison; but inferences drawn from this fact are apt to be erroneous, since none of these places was well fortified according to modern methods, well garrisoned, well supplied, and defended to extremity. The results show, however, that under similar circumstances, which are apt to arise in any modern war, the attack of a strong place which can be completely invested by a force of two or three times the strength of the garrison, may promise success; which seems to be assured if the defence allows the besieging force to complete the investment and thoroughly intrench itself. On the other hand, tactical considerations would indicate that a well-equipped army, of good morale, under an active and aggressive commander, covered by a modern intrenched camp, should be able to prevent the investment; and by taking advantage of its interior lines, its heavy guns and its strong _points d’appui_, should be able to beat in detail a force very much greater than itself whose fractions, by reason of the extent of the line of investment, are necessarily not within supporting distance of each other. These advantages of the defence evidently disappear, as above indicated, when the attack is allowed to complete its fortifications, since under their cover a small force can check even a determined sortie until a sufficient force to beat it can be concentrated. From these considerations it is evident that an investment, once completed, may be maintained by a force less than that necessary to establish it in the first place (see Investment of Plevna, Pierron, Méthodes de Guerre Vol. III, pp. 647 _et seq._). =75.= =The Point of Attack.=--From the information originally in possession of the besieger, supplemented by that obtained by reconnoissance, a decision is made as to the fronts of the work or the particular detached works of the intrenched camp upon which the approaches are to be made. The portion selected in either case is called the “_point of attack_.” To reduce an intrenched camp, it will in general be necessary to capture at least two of the detached works and to silence the artillery fire of one or more on each side of those taken. In an attack upon a strongly-fortified enceinte, the least that is usually undertaken is to breach and capture one front with its adjacent outworks, and to silence the fire of those which enfilade the approaches and parallels or take them in reverse. In selecting the point of attack the first consideration is, that when taken, it shall afford material advantage to the besieger and give him a foothold from which further approaches may be driven, if necessary. This condition being fulfilled, the choice will result from a careful study of the nature of the works and site. Those forts or fronts resting upon precipices, bordering deep marshes or deep and rapid streams, or which are so placed that approaches upon them will be swept in flank and rear by the fire of the works, which cannot be silenced, are considered impregnable by the ordinary operations of the siege. Most serious difficulties are presented by those in which the adjacent works are so disposed and of such strength that they can be carried only in succession and by regular approaches; those provided with wet ditches in which strong currents can be produced, those with dry deep ditches, those which are mined, and those which present long lines nearly straight, or even concave to the attack, and covering a front nearly equal or even greater than can be occupied by the trenches of the besiegers. When the parallels and approaches have to be constructed upon ground sloping downward towards the work, in soil containing large stones, or in which the rock is close to the surface, in marshy ground or that containing much water or liable to be flooded, the difficulty of their construction and defilade are evident. The point of attack considered most favorable to the besieger is one which, fulfilling the first essential condition, is more or less salient, so that it can be partially surrounded, and which admits of the approaches being driven toward it in favorable soil, over ground sloping gently from the work, or gently rolling with the crests and valleys of sufficient difference of level to afford cover, and running generally in the direction of the parallels. A favorable location for parks, etc., with free, safe, and short communications between them, also has great weight in selecting the point of attack. SECOND PERIOD. =76.= =First Artillery Position.=--Every siege begins with a bombardment, which is designed, as previously stated, to drive in the outlying posts of the defence, to silence, so far as possible, the artillery annoy and wear out the garrisons of the works to be attacked, to interrupt the communications between them, break up bomb and splinter proofs, destroy magazines and depots, and, if the enceinte can be reached by the artillery, to bring a fire upon the population which will lead to or hasten the surrender of the place. The considerations which determine the location of the batteries for the general bombardment have already been given (par. 7), as well as the construction of the batteries and screens used (Chap. IV.). For the systematic attack, however, the necessity of dismounting or silencing the guns bearing upon the proposed approaches introduces the additional condition that the batteries should be so located that besides their general effect each shall fulfil, so far as practicable, its special design by bringing an enfilading or reverse fire upon certain fronts; or, in connection with other batteries, shall keep down the fire of certain fronts by a preponderance of direct fire. Many batteries which fulfil these last conditions occupy their original positions during the entire siege. The requisite concentration of fire upon the point of attack and its careful regulation for the special object in view will frequently restrict the arc occupied by the batteries below that desirable for a general bombardment only; and will necessitate a closer grouping of the batteries for their easier control by the artillery commanders. This line of batteries first established is known as the “_first artillery position_” (Pl. VIII., Figs. 80, 81). As the batteries must be secure against the attacks of the defence, they must of necessity be outside the besiegers defensive line. Their distance in yards will result from the character of the defence and may vary from 2000 or 2500 yards for a weak defence, to 3500 or 4500 yards for an active one. On account of their long range and the object to be obtained by their fire, they are armed with the heaviest rifles and howitzers available, supplemented with rifled mortars of as large calibre as can be obtained, firing, if practicable, torpedo shells charged with high explosives. Batteries of field guns which have already been favorably located for the defence of the heavier batteries against attack, or for firing upon the more advanced works, may, by modification of their gun pits into finished batteries (par. 44), be used in conjunction with the heavy batteries of the first artillery position. The total number of guns employed should be such as to give to the attack a marked superiority over the defence at the opening of the bombardment. =77.= =Opening Fire.=--The batteries having been completed and armed, the magazines finished and supplied, and the parks, depots and communications put in such order that the batteries can be kept fully supplied with ammunition; the fire of the batteries is commenced simultaneously, the signal being given by a gun from some selected battery. The fire once opened is continued day and night during the siege, unless stopped by the commanding officer or from inability to keep it up. It usually begins at daylight, in order to enable the ranges to be corrected by the first shots, before the defence has accurately located the batteries unmasked during the preceding night. To open fire from a few batteries before the others are ready is inexcusable, as it enables the defence to concentrate its fire upon them and destroy them in succession. The targets of each battery and gun and the rate of fire are prescribed before the fire is opened, and these are changed only by subsequent orders or from sudden emergencies. The fire is as a rule deliberate, seldom exceeding an average of 4 shots per hour for each gun by day, and 2 per hour at night. This rate may be increased or diminished by the commanding officer for special reasons and for a limited time. The fire of the batteries is directed upon all the works of the place within range, but with greater vigor upon the more important, and especially upon those near the point of attack. The fire against powder-magazines and storehouses should be uninterrupted, to prevent the removal of powder and munitions. If the artillery of a part of the work is silenced, the fire upon it may be slackened, but some fire, especially vertical, should be kept up. At night the fire is directed against the larger targets, such as communications and covers, rather than upon the guns; but the fire against the interior of the place (especially a city) is kept at about the same rate day and night. If preparations for a sortie are detected, the fire of the large pieces is directed at the points of assembly, when known, and at the openings through which the sortie is to be made. The field guns direct their fire upon the troops in accordance with the tactical use of this arm. If the batteries of the first artillery position have the proper preponderance over those of the place, they should soon clear away the advanced posts, and keep down the fire of the works so that the besieger may advance his outposts, control the exterior ground and prepare to open the first parallel and establish the second artillery position. =78.= =Plan of Attack.=--By this time the reconnoissances and surveys should be so far advanced and so thoroughly checked up that the chief engineer will have been able to make, upon a large scale, a map of the place and its surroundings with considerable accuracy, and to locate upon it the proposed position of the first and second parallels, the approaches, and the batteries of the second artillery position. This map, with the accompanying memoirs, makes up the “_plan of attack_,” which, when approved by the commanding general, serves as a working plan for the prosecution of the siege, and is continually corrected and added to as the siege progresses. This map should be made in duplicate at least, and for accuracy in the history of the siege should be corrected so far as possible by redrawing or tracing, instead of by erasures. =79.= =The First Parallel.=--The first parallel (Pl. VIII, Figs. 80 and 81) serves as an intrenchment for the troops who protect the second artillery position and who cover the workmen driving the approaches. It also affords a covered communication between the different lines of approaches. Its length must be sufficient to cover all the batteries of the second artillery position and protect their flanks; it must therefore extend beyond the batteries which enfilade those faces of the fronts attacked whose prolongations fall furthest out. Its flanks are usually more or less refused, and terminated by strong earthworks. Emplacements for batteries of field guns are provided at intervals to assist the infantry in repelling sorties. When the length of the parallel is very great, it is sometimes not continuous when first opened, but the portions covering the groups of batteries are first made and are subsequently connected. The ground between them is protected, meanwhile, by a strong fire of small arms, field and other guns. When communications covered by natural screens do not exist between the first parallel, the batteries of the first artillery position, and the parks, approaches are constructed at the same time as the parallel, in sufficient number to give free passage to the troops, guns, and materials. These approaches (Pl. VIII, Figs. 80 and 81), as all others (par. 13), are so directed as not to be enfiladed by the fire of the work, and should be provided with portable or other tramways and cars, passing switches being placed in the returns where needed. =Its Distance from the Work.=--As a rule, it may be stated that the first parallel is placed as near the work as possible. Most of the batteries of the second artillery position are from 100 to 300 yards in its rear, and the shorter their range the more effective is their fire. The small-arm fire from the first parallel may also be an important feature in modern sieges; to make it so requires the parallel to be located within 1500 yards of the work, if possible. By placing the parallel as near the work as possible, its length and that of the saps are correspondingly reduced, the amount of work lessened, and generally the fall of the place hastened. If an attempt be made to place it too close to the work, however, the working parties will be discovered; they will be within reach of strong sorties, and of the deadly fire of small arms and machine guns; in consequence of which they may suffer very great losses, be driven off, and the construction of the parallel prevented. The minimum distance under the most favorable circumstances is then about 600 to 700 yards. (This was the distance prescribed in the day of smooth-bore guns, and was adopted as recently as 1870 at the siege of Strasburg.) In an open, level country it may not be possible to place the first parallel at a distance from the most advanced work of less than 1800 to 2000 yards. When, however, it is necessary to establish the first parallel at a very great distance, it will not, as a rule, be made continuous, but in fractions covering approaches which are driven forward. The first continuous parallel is then built at from 1000 to 1200 yards from the works, and behind this the second artillery position is established. =80.= =Opening the Parallel.=--The profile of the parallel is one of those already given (Pl. I, Figs. 7-13), and it is traced and constructed as described (pars. 14, 18, and 19), by simple trench, flying sap, or full sap, as may be most advantageous. In some cases, however, it is constructed by enlarging the line of shelter trenches already made by the outposts. To cover the working parties while excavating the trench, when the parallel is near enough the work to be endangered by a sortie, the outposts are advanced to about 300 yards in front of the line, the pickets and supports are posted respectively at about 100 and 200 yards in their rear, and are covered by rifle pits and trenches made for this purpose during the preceding nights. To conceal from the defence, if possible, the proposed location of the parallel, these trenches and pits are constructed by all the outposts in front of their positions. The reserves are held 800 to 1000 yards in rear of the flanks, and the whole covering force should be equal to 1/2 or 2/8 the garrison of the place if an active defence is looked for. At daylight the trenches will be far enough advanced to protect the covering force which will occupy them. This force is from this time known as the “_guard of the trenches_,” and is relieved usually every 24 hours, the time of relief being so chosen as not to interfere with the working parties. The working parties are, as previously indicated, divided into reliefs of 4 or 8 hours. For continuous work the besieging force should be large enough to allow each man, after being one day in the guard of the trenches and one day in the working party, to have one day in camp. =81.= =The Second Artillery Position.=--By the second artillery position previously referred to is meant the position occupied by the guns of the attack, placed in batteries, accurately located for breaching, enfilading, counter-battering or other specific duty. These batteries are usually of the class described under the head of “exposed sunken batteries” (Plates V, VI, VII), and are constructed behind or in the parallels, as explained in pars. 48 to 55. When behind a parallel they should be, if possible, at least 150 yards from it in order that the blast of the guns shall not interfere too much with the occupants of the parallel. =82.= =Counter-batteries=, designed to dismount guns or destroy embrasures of earth or masonry at ranges from 700 to 1000 yards by direct fire may well be armed with 4½ or 5 inch rifles, since their projectiles have sufficient energy for the desired result, and the guns admit of a more rapid and long-continued fire than do those of greater calibre. The batteries must be so placed as to look through the embrasure attacked, and the number of guns pitted against any battery must considerably exceed that in the battery. Counter-batteries designed to silence by direct fire guns in turrets or behind shields must be armed with guns of large calibre, mounted with the best available cover, and must be aided by rapid fire guns of moderate calibre, designed to disable the turret guns either by embrasure shots or by oblique shots penetrating the parts which project from the turret. =83.= =Enfilading batteries= act in conjunction with counter-batteries or independently; they are designed to take the faces in flank or slightly in reverse, but are of necessity at times limited to a slant fire. They are located as nearly as possible in the prolongation of the terre-pleins. When the salients are obtuse these prolongations lie near the adjacent faces for some distance, and consequently the only possible emplacements of enfilading batteries will give ranges which may vary from 1000 to 4000 yards. They are armed with cannon of sufficiently large calibre to make their projectiles efficient even at moderate velocities, and, when the faces enfiladed are well provided with traverses, the charges are reduced so as to give to the projectiles a large angle of fall. When the batteries are on commanding heights higher velocities may be used. =84.= =Breaching batteries=, except those established on the crest of the counterscarp, can only breach the walls of modern forts by “curved” or “indirect” fire. To obtain the necessary angle of fall with the requisite accuracy and energy of blow, the guns must be of considerable size and placed at comparatively long range; the projectile must graze the crest of the glacis and strike the scarp wall at an angle not too oblique. Experience seems to indicate that the best effects are obtained, all things considered, when the vertical plane of fire makes an angle of from 55° to 60° with the face of the scarp wall. The distance of the battery from the wall to be breached is usually from 1000 to 1500 yards. The same considerations govern the construction and armament of batteries designed to destroy réduits, barracks, gorge walls, city gates, magazines, depots, bridges, locks, etc., etc. =85.= =Batteries of rifled mortars or of howitzers for vertical fire= should be so located, when possible, that the longest dimension of the target will be in the direction of their fire. The effect of their projectiles is greatest when they can be fired at elevations, of 60° to 70° and with large charges. These considerations, combined with those of good cover and easy supply, will govern their location. =86.= =Opening and conduct of fire from Second Artillery position.=--The batteries which are ready on the morning of the completion of the parallel open fire simultaneously upon the work, and are supported by those of the first artillery position still armed. The same rules govern the fire of the first and of the second artillery position. When the defence combines a number of batteries to silence one of the attack a heavy fire is concentrated upon these batteries by those from which the fire has been diverted. New batteries unmasked by the defence, or established in intermediate or other works, should receive prompt attention from the attack, with a view to silencing them if possible before they correct their ranges. It is of the first importance that the superiority of the artillery fire of the attack shall be established at the opening of fire from the first artillery position and be maintained throughout, and that the defence shall be prevented from repairing any batteries which have been silenced. To this end a few guns will keep up a slow fire upon these batteries so long as it may be necessary. Every gun of the defence must, if possible, be kept under a heavy fire, and the fire upon the enceinte must be opened at the earliest possible date and continued day and night, as previously described. =87.= =Musketry fire= will be opened as soon as a parallel is established at such distance as to make it effective; and this may be, for a well-regulated fire of sharpshooters, at ranges of 1200 to 1500 yards, or in some cases even greater. =88.= =The Advance from the First Parallel.=--It is assumed that the fire from the first and second artillery positions will silence almost completely the artillery fire of the work upon the fronts attacked; but the defence will still be able to develop when necessary a strong musketry fire, aided at times by machine and rapid-fire or even some field guns. Consequently, the advance from the parallel must be under cover. Approaches are, therefore, broken out from the parallel and pushed forward towards the work, the workmen being protected by the fire of the guards of the trenches. Usually at least three lines of approaches are constructed, concentrating upon the point of attack and following generally the lines of the capitals of the adjacent salients. When attacking a line of detached works two or more lines of approaches may be constructed towards each work attacked. The approaches are run in zigzags, each branch so directed as to pass a short distance (30 or 40 yards) outside the most advanced work of the defence from which it could be enfiladed; at each change of direction of the zigzags a return of 10 or 20 yards is made to cover the approach in rear (Pl. VIII, Figs. 80 and 81). The length of the branches is so regulated as not to mask too much of the front of the parallel; they consequently grow shorter as they approach the work and vary ordinarily between 200 and 50 yards, seldom exceeding 100 yards when near the work. The heads of the different approaches are advanced at about equal speed so as to afford mutual support. =89.= =The Second Parallel.=--The second parallel is located nearer to the first parallel than to the covered way, sometimes very much nearer. It is constructed and occupied by the guard of the trenches. The principle followed is that the guards of the trenches shall always be nearer to the head of the sap than is the enemy in his most advanced place of arms; so that, in case of a sortie, the advantage will lie with the besieger. The flanks of the second parallel are refused and strengthened like those of the first, or are even carried back to the first parallel, to guard them against flank attacks. The second parallel having been completed and occupied, serves as a base for further advance, which is conducted according to the same methods, “_demi-parallels_” (Pl. VIII, Fig. 81) being run out to the right and left of the approaches when they are well advanced beyond the second parallel. These demi-parallels are sometimes joined, forming a third parallel, from which the approaches are advanced as before, with additional parallels when needed, until the foot of the glacis or exterior of the counter-mines is reached. The number of parallels is determined by the distance at which the first is established and the vigor of the defence; formerly three were considered all that were needed, and this number was used at Strasburg, 1870. At other modern sieges a larger number has frequently been required. At Belfort (1870-71) the third parallel was established at 1200 yards from the place. Five parallels were used at the siege of Fort Wagner (July-September, 1863). The approaches are driven in zigzags by simple trench, flying or full sap, until the direct advance becomes equal to about one third of the length of trench; and from this point they are driven directly upon the work by double-traversed sap (Pl. III, Figs. 28-35), the latter being, as a rule, used only in advancing from the foot of the glacis, or during the third period of the siege. THIRD PERIOD. =90.= =The Third Period of the Siege= frequently called the “_close attack_,” includes all the steps between establishing the last parallel and the surrender of the place. These are the capture and crowning of the covered way, breaching the scarps and counter-scarps, passing the ditch, capturing and crowning the breaches of the outworks and main works in succession, and the final reduction of the interior retrenchments, or keep. All these operations are carried on within close and deadly range of small arms and shells of Coehorn mortars, and many of them within range of hand grenades and upon ground honeycombed with mines and countermines, or liable to be flooded or inundated. They are slow in progress, uncertain in results, and require an extravagant expenditure of men and material. They can be pushed to a successful issue only when the artillery fire of the place is silenced and its small-arm fire is almost completely kept down by the fire of the attack. The conditions of modern warfare are such, however, that by the time the attack has reached the foot of the glacis the losses and exhaustion of the garrison are frequently so great as to preclude an obstinate, close defence; and, in the majority of cases, the place is compelled to surrender before the close attack is commenced. =91.= =The capture and crowning of the covered way= is accomplished by _assault_ or by _sap_. The former is an extremely hazardous and bloody operation, which all authorities unite in condemning, and which should be undertaken only in extreme cases. It is carried out usually at night, by forming an assaulting party in the parallel, who rush forward to the crest of the covered way; capture, if possible, its guards, and under any attainable cover open a fire upon the crest of the work. All available small-arm and machine-gun fire combines with this to keep down the fire of the defence; and under cover of this fire the working parties construct, by flying sap, a trench crowning the covered way, and the communications between it and the parallel. The trench is occupied as soon as it affords cover, and is subsequently completed and prepared for the reception of its guns and infantry guard. In crowning the covered way by sap (Pl. IV, Fig. 36), the saps are broken out from the parallel, a circular place of arms is constructed, which gives additional communication and serves as a depot for trench materials, the traversed sap is pushed forward, and the covered way crowned as previously described (par. 36). It will frequently be necessary to run out at right angles to this sap short branches of parallels (Pl. IX, Fig. 83), to serve as places of arms, or as trenches of departure for mines or galleries, for underground warfare or for breaching walls. =92.= =Breaching the Scarps and Counter-scarps.=--The counter-scarp, as a rule, and the scarp at times is breached by mining. (See Military Mining, pars. 91-93). When practicable, however, the scarp is breached with artillery and preferably by guns of the second artillery position; since a breaching battery on the crowning of the covered way, which must be provided with most ample splinter-proofs to protect the gunners from flying splinters of masonry and shot, is in general constructed only with great losses and delays; and the guns in this position must be fired under great angles of depression, requiring very deep embrasures to avoid exposing the cannoneers. When the ditch is deep and narrow it may be necessary to blow down the counter scarp and part of the glacis, in order to expose the scarp-wall to the fire of the breaching battery, whether on the glacis or at a distance. This necessity should be foreseen and provided for in locating the batteries. A full or semi-detached scarp-wall will be breached when the battery is on the glacis by making vertical cuts at the ends, and a horizontal cut at about one third or one fourth its height from the bottom, and then firing shells into the part to be brought down, continuing the fire until the large masses of masonry are broken up, and the slope is made gentle and smooth enough to admit of easy ascent. A detached scarp-wall will be breached by a glacis battery, or any scarp-wall by a distant battery, by continued battering, which will not only knock down the wall, but also break up the fragments and make a practicable ramp. =93.= =The Capture and Crowning of the Breach.=--The decision as to whether the breach shall be captured and crowned by _assault_ or by _sap_ will be governed by considerations similar to those which determined the character of the attack upon the covered way. The difficulties and dangers of the assault are perhaps greater than in that case. The =assault=, if undertaken, will be carried out in a similar manner, previous preparations having been made by making a practicable breach at least 25 to 30 yards wide, a practicable descent into the ditch of equal width, and a covered place of assembly for the working party and a depot of trench materials in immediate proximity to the breach. The artillery defence of the ditch, whether from caponières, flank embrasures or casemates, or from adjacent works, must of course be silenced before crossing the ditch either by assault or by regular approach. This is accomplished by counter-batteries on the glacis, by heavy field guns located in temporary batteries in the trenches, by mines, or by overhead or indirect fire from the distant batteries, or from light mortars in the advanced trenches, as may be necessary. If the interior arrangement of the work is known by the besieger the assault maybe made by night; but if it is unknown, the confusion resulting from a night attack will be so great as to render its success almost hopeless, and the assault will have to be delivered by day. The assaulting columns will be made up of an advanced line of skirmishers (selected men, good shots, and generally volunteers), followed by a working party of sappers to clear away obstacles, these closely followed by the columns of assault; while the supports and reserves move forward in the trenches to join in the assault as circumstances require. The troops who first gain the crest establish themselves there and hold the breach until those coming after them pass and engage the garrison, while some detachments strive to capture and open one gate or more to admit the reserves. The assaulting force should be equal at least to once and a half or twice the garrison, and simultaneous attacks should be made upon other breaches or accessible parts of the work to divide the attention of the defence. These false attacks are sometimes successful, and preparations for taking advantage of this contingency should not be omitted. The subdivisions of the assaulting force should each receive explicit instructions as to its special object, and under no circumstances should their lines of march intersect. Unmistakable signals of recognition should be prescribed to prevent conflicts arising between the different parties meeting within the work. The bombardment preceding the attack should not cease, and thus notify the defence when the assault is to be made; but the guns should be directed upon adjacent parts of the work until the assault penetrates the work or is repulsed. =94.= In the =attack by the sap= the method of crossing the ditch adapted to the circumstances is used (pars. 39-41, Pl. IV, Figs. 37-41) and the sap is started at the foot of the breach, driven up it, and the breach is crowned according to the methods previously described (par. 36). The sappers are protected from small sorties by the fire from the crowning of the covered way and any other points bearing on the head of the sap. Fireballs, electric lights and other means will be used during the night to light up the parapets of the work and expose the defenders, in this as in the previous operations of the siege. The crowning of the breach will be extended and converted into a place of arms, from which further sapping can be carried on in a similar manner, until the breach in the last retrenchment is crowned and the preparations for the final attack upon the garrison are made, or the place surrenders. If the garrison takes refuge in an interior keep and continues the defence the keep must be reduced by similar methods. =95.= =Additional Operations in the Attack of an Intrenched Camp.=--The operations above described are those necessary to reduce a fortified place of the older type, or a detached work of an intrenched camp. The latter, though of less extent and with a smaller garrison, offers as a rule greater resisting power, since it is usually subject to front fire only, has more complete bomb-proof cover, and is free from the presence of non-combatants. While a great advantage is gained by the capture of two or more of the advanced forts, the resisting power of the intrenched camp is by no means destroyed. These forts are subject to the fire of the collateral works, of which frequently two or more must be silenced before a further advance can be made. The beleaguered army may still be in condition to recapture the forts by vigorous assaults; and in almost every case, before the fall of the works of the outer line, a line of provisional fortifications of high resisting power, connected by trenches, will have been constructed by the defence in rear of the captured works, with its flanks secured by the collateral works of the outer line. An assault against works of this class offers no prospect of success. The besieger is therefore obliged, as soon as he captures a detached fort, to put it in condition to withstand the assaults of the besieged army and to afford protection from the artillery fire of the collateral works, and then to push forward his approaches against the successive positions prepared by the defence, which will as a rule present a front equal to or greater than that which can be occupied by the attack. The gorges of the captured works are repaired and strengthened, covered communications are made through the faces, either through the breaches or in more convenient points, traverses are repaired or built to protect against the fire of the collateral works, and the captured works are connected by trenches which afford emplacements for batteries and form a new parallel from which the saps can be driven in attacking the intermediate works. Simultaneously with this attack, it is usually advisable to advance from the flanks of the first or second parallel upon the forts of the outer line which form the flanks of the intermediate line. The approaches can generally be driven with comparative ease owing to these works having already been partly disabled and now being subject to a flank and reverse fire from the newly-established batteries. The flanks of the intermediate line being turned by the capture of these works, a portion or the whole of it will of necessity be abandoned. The subsequent operations up to the capture of the enceinte will be of the same nature as those already described. =96.= =Occupation of a Conquered Place.=--Immediately upon the fall of the place it must be occupied by a force (chosen when possible from the reserve which has not participated in the final assault) sufficient to control not only the inhabitants, but also the disorderly soldiers of the attacking force. All pillaging, wanton destruction, and abuse of the conquered must be restrained with a strong hand, immediate and exemplary punishment being inflicted upon offenders. The orderly portion of the defenders must be protected, and such steps taken for supplying their needs as humanity requires; while the disorderly ones must be repressed with such severity as may be necessary. So soon as order is established a careful inventory of captured property is made, and it is stored subject to the orders of the government. When the possibility exists of the place being attacked or besieged by the enemy, all its resources which are available for defence are collected, repaired, and stored for use. VAUBAN’S MAXIMS. =97.= Marshal Vauban, the great French military engineer (born 1633, died 1707), whose experience and success in sieges made him the great authority on the subject, formulated certain maxims for governing the conduct of a siege, the observance of which led to almost certain success, and the departure from them almost invariably resulted disastrously. The most of these are as applicable to sieges of to-day as they were to those of his own time. The following[6] bear upon the second and third periods of the attack: 1st. To delay the opening of the trenches until the besieging forces are all well posted and made secure by fortifications from an attack either from the garrison or from a succoring force; and until everything requisite for carrying on the work vigorously has been collected and is ready at hand when wanted. 2d. To make a single attack rather than a double one, unless the two attacks can be well connected and the besieging force exceeds considerably in strength the garrison. This, as a matter of course, excludes false attacks, and double separate attacks, unless the superiority of the besieging force is very great. By a single attack is understood one by which it is proposed to gain possession of the main work by a single breach at some point; by a double attack it is proposed to effect two breaches of the main work. The advantage of the latter lies in forcing the garrison to divide their strength for the defence of the two breaches, whilst the assailing forces, being under one leadership, can at any moment concentrate if necessary upon the point most favorable to their assault. 3d. To embrace within the parallels and approaches all the defences which bear upon the site to be occupied by the besieger’s works, in order to have secure positions for establishing the batteries that may be required to silence the fire of these defences. 4th. To multiply the approaches, with the view of giving mutual support, less encumbered communications, and dividing the fire of the defences, which, if concentrated upon a single one, might soon destroy it. 5th. To throw up at least three main lines of parallels, placing them in the best positions for mutual support and for guarding the approaches and batteries from sorties of the besieged. 6th. To avoid attacking a point upon which the approaches can be run only on a narrow front, or one which can only be approached over marshy ground, or on causeways. 7th. To be careful not to push forward any portion of the trenches until they are well flanked and protected by trenches in their rear, which are completed and occupied by troops. 8th. To avoid encumbering the approaches with trench materials, tools, workmen, or troops; placing all of these in the parallels, on the right and left of the approaches, so as to be ready at hand when wanted, and to be rapidly sent forward through the trenches of the approaches, which should be kept free for this purpose. 9th. To place the ricochet (enfilading) batteries in such positions that they can have an enfilading and slant reverse fire upon the guns of the defences to be attained by them. 10th. To refrain from opening fire from any series of batteries until it can be done at the same moment from all of them. [In connection with this and other siege operations, Vauban remarks that precipitation in sieges does not hasten the close of them, but often prolongs them and renders them more bloody.] 11th. To employ the fire of the batteries and trenches, rather than open assaults, to drive the besieged from their defences, before attempting to occupy them by the besieging force. 12th. When it is decided to make an open assault, to do so by day, if there is no portion of the fire of the defences which bears upon the point to be carried that is not completely kept under by the fire of the batteries and trenches; but, in the contrary case, when the fire of the defences is not completely kept under, to make a night assault. 13th. Not to attempt an obstinate resistance to an open assault of the besieged upon any unfinished portion of the trenches; but rather to withdraw the workmen and the few troops near them to some point behind the parallel immediately in rear, and then to open a vigorous fire from it upon the assailing force. 14th. To keep within the cover of the parallel when the assailant is advancing to the assault, and leave him to expose himself to its fire as long as he pleases, and then, when he is well cut up, and has got thrown into confusion, as he necessarily will at night, in the trenches that he may have carried, to fall upon him with the bayonet and drive him out. 15th. Not to push such charges too far from the parallel, but to retire promptly, so soon as the assailant has fairly taken to flight, within the cover of the parallel, so as not to draw the fire of the besieged works. JOURNAL OF THE ATTACK. =98.= In connection with the plan of attack previously referred to (par. 78), a complete _Journal of the Attack_ will be kept in which will be recorded day by day a detailed record of the daily progress of the siege, giving the day and hour of starting and completing each battery, parallel, approach, etc., with their daily progress, dates of opening fire from each battery, and, generally, every incident connected with the siege. This journal will be supplemented by journals kept by the chiefs of engineers and artillery, in which will be consolidated the daily reports of all subordinate commanders of these respective arms, giving the expenditure of ammunition, the performance of the guns, carriages, etc.; the modification made in details of parapets, batteries, magazines, etc., with their value; the results of trials of new devices, and special reports upon any points connected with the siege. These journals will be carefully preserved and copies transmitted to the War Department from time to time for future use. CHAPTER VI. THE DEFENCE. =99.= =Preliminary Considerations.=--The defence of a fortified place is entrusted to a commanding officer, who, when the siege is established, is generally known as the “Governor of the Place.” His duties become more exacting and his powers more absolute from the beginning of hostilities until the place is invested and cut off from communication with the exterior, when, since the whole responsibility of the defence rests upon him, his powers over both the garrison and the inhabitants of the place, of necessity become autocratic in all matters affecting the defence, directly or indirectly. He, of course, avails himself of the counsel and advice of his subordinate officers and may make up a “Council of Defence” from his second in command and the commander of the engineers and of the artillery; but the ultimate decision of all questions must rest with him alone. During peace and after the beginning of hostilities up to the near approach of the investing force, the civil authorities retain their ordinary jurisdiction, unless martial law is declared by proper authority; but after the place is invested, martial law (or state of siege) exists from necessity, and the police power, the control of provisions and supplies of all kinds, public and private, buildings, animals, vehicles, etc., and everything necessary for the defence of the place fall into the hands of the governor, who also is empowered to direct who shall be sent out and who shall be retained within the place, and what necessary service or labor shall be performed by the inhabitants. Having been selected for these onerous and exacting duties, he, under no circumstances, allows himself to be cut off from his post, and is therefore debarred from leading his troops in person in the active operations outside the work or exposing himself unnecessarily or recklessly during any period of the siege. =100.= =The Garrison.=--The garrison should consist of artillery and infantry, and, in an intrenched camp, of enough mounted troops for escort, messenger, and a limited vedette service. The strength of the infantry is generally regulated so as to give a suitable garrison to each detached work, and about 1½ to 2 men for each yard of the front of attack. The artillery is allowed about 12 men for each gun. The number of engineers is determined for each place by the probable amount of engineer work that will be required. These troops make up about one-third of the entire force. A general reserve of all arms (principally, however, foot troops) makes up the other two-thirds, and is held as “a fighting force” for preventing the investment of the place, or for breaking up the investing lines when established. This reserve is called upon for work on the front of attack or in the trenches only when it cannot be avoided. In smaller places the portion of the garrison called upon for the outer line of defence may be increased to one-half or two-thirds, and the general reserve be reduced to one-half or one-third of the entire force. When the investment is strongly established the general reserve will usually be combined with the other troops. The troops engaged on the front of attack are usually assigned to the different sectors of attack and are divided into reliefs (ordinarily three), each relief having as a rule a tour of one day in the front lines, one in the immediate supports, and one in the reserve and in interior fatigue duty. The Governor, however, so regulates the details as to impose upon the troops the least work consistent with an energetic defence. =101.= =Armament.=--The guns for arming the place should be placed in position or in store within the works before the beginning of hostilities. There should be mounted in commanding positions a sufficient number of high-power guns to hold the enemy’s first works at a distance and to fire upon his camps, etc., if placed too near. In addition to these, a full supply of light guns, including machine and rapid-fire guns, should be at all times equipped and supplied for immediate use in meeting an assault or surprise. Their emplacements, platforms, etc., should be in readiness for use at any moment. In large places and for an active defence there will be needed also enough field-guns to properly equip the general reserve (about 4 guns per 1000 men). These should be considered a part of the equipment of the reserve. It being, from economical considerations, impossible to supply guns to fully arm all the fronts of a place, enough only are usually provided to thoroughly equip the sector of attack and to replace those disabled. These are stored within the place where they are secure against deterioration or injury, and are mounted in the sector of attack when it is definitely determined. The numbers of high-powered guns, howitzers, mortars, and machine and rapid-fire guns needed must be determined from the size of the place, its garrison, and the character of attack which may be expected. =102.= =Ammunition, Provisions and Supplies.=--A plentiful supply of ammunition, especially of projectiles, for all the guns should be kept constantly on hand. The projectiles, which may be stored for an indefinite term without deterioration, may be distributed in magazines in proximity to their batteries; the powder should be so stored as to preserve its properties, and be distributed to the service magazines at such times and in such quantities as may be necessary. Other equipments will be stored and handled in accordance with the same principles. The utmost care will be taken in storing and issuing the provisions and supplies belonging to the troops; and in cases of necessity during the siege the sales of provisions to the inhabitants by the dealers will be regulated, both in prices and quantities, by the military governor. =103.= =Sanitation and Hygiene.=--The most rigid sanitary measures and rules of hygiene should be enforced from the beginning of the siege, under the direction of the military governor, whose medical officers should join with the health officers of the place (if any exist) in guarding not only the troops but all the inhabitants from all avoidable causes of epidemic diseases. Extreme rigor in carrying out these regulations in not only allowable, but is most urgently required. =104.= =Preparations for Defence.=--An active defence being presupposed, all possible measures for its execution should be taken before the near approach of the enemy interferes with them. The principal ones are as follows, viz.: Advanced posts are established as far from the work as is prudent, say 3500 to 4000 yards, placed at points which may be easily defended or which would be advantageous positions for the enemy’s batteries, etc. These, when possible, should be so placed that the ground between them is swept by their infantry fire and by the artillery of the place. They should be provided with good cover for the troops, and parapets for infantry and field-guns. When not naturally strong, field-works should be built. Quarries, ditches, sunken roads, villages, woods, etc., should be taken advantage of, either as points of defence, passive obstacles, or covers for communications, as may be best. Lines of retreat to the work as secure as possible from hostile fire should be provided. All supplies in the vicinity of the work which will be useful during the siege should be collected and taken into the place. Means of communicating with the exterior by telegraph, telephone, signal flags, lanterns and heliotropes, carrier-pigeons and balloons, should be secured. Search-lights for illuminating the exterior should be obtained, and as soon as practicable bomb-proofs and shelters for the inhabitants should be prepared in the body of the place; and in connection with the civil authorities the fire department of the place should be organized and taught how to extinguish fires with dry earth and by pulling down buildings when water is not available. The service of security and information should be extended to the furthest possible limit, not only by outposts, etc., but by telegraph operators and reliable correspondents at long distances from the place; and preparations should be made to retard the approach of the enemy by the destruction of the roads, bridges, etc. =105.= =Defence during the First Period of the Siege.=--Upon the approach of the enemy each work should receive its permanent garrison, and the fighting reserve should go out to occupy the advanced posts and to take full advantage of its interior lines to hold him back and punish any careless or ill-advised advance, being aided in this when possible by the fire of the heavy guns of the place. Care must be taken to avoid too great dispersion of the troops, and exposing advanced parties to being cut off and captured by pushing them too far to the front or holding their positions too long; but no opportunity should be missed of attacking and destroying or beating back hostile detachments when tactical conditions warrant it. The defence during the first part of this period differs but little from the ordinary defence of an intrenched battle-field. The principal differences arise from the fact that the flanks of the advanced lines and the lines of retreat to the work are so well covered that with ordinary precautions they may be considered secure, and all energies may be directed to meeting the front attack and executing offensive returns. So soon as the point of attack selected by the enemy becomes known the advanced positions may be more fully manned and equipped; trenches with inconspicuous parapets, or preferably without any, may be made to cover the infantry, field-guns, and sometimes siege-guns on travelling carriages. These positions may be, as previously stated, 2500 to 3000 yards from the permanent works, and the intervals between them may be swept by the heavy guns of the latter. If these positions can be so strongly held as to compel the besieger to attack them with his heavy guns, he will be compelled to establish his first artillery position at a very great distance--possibly 5000 to 6000 yards from the work. [At Belfort, 1870, positions of this kind were taken only after seventy-seven days of siege.] As the advanced positions may be subject to the fire of the heaviest class of siege-guns, if any parapet is made it should be of the nature of a glacis of gentle slope and little command. Infantry trenches should be made narrow and deep as a protection against shells and shrapnel (Pl. IX, Fig. 84), and gun-emplacements should be as small as practicable and almost entirely in excavation, for the same reason. Positions so prepared suffer very little from gun-fire, and will frequently require attack by systematic approaches. An efficient outpost service must be maintained in front of these positions to prevent their being taken by surprise. When but a limited number of troops are available for defence it is of course impossible to push out the advanced posts so far to the front. In all cases, however, they should be placed at the greatest practicable distance. =106.= =Opening of Artillery-fire by the Defence.=--The artillery-fire of the defence should be opened upon the besieger’s batteries, etc., before they are ready for action, so that the ranges may be obtained and the tables of fire corrected without interference by the hostile fire. If this can be accomplished, the increased effect due to the accurate fire of the defence may more than counterbalance the numerical superiority of the attack, and result in preventing the completion of some of his batteries and in silencing others. If, on the other hand, the attack anticipates the defence in obtaining the range, his superiority in numbers and accuracy will frequently necessitate abandoning some emplacements and mounting the guns in others, where they may be used in the later stages of the siege. =107.= =Defence during the Bombardment and Assault.=--The amount of ammunition which can be profitably expended by the defence during the bombardment must be determined by the quantity on hand and the advisability of exposing by their fire the positions of the guns. The infantry troops and the light guns are held under cover, ready to be moved forward to meet the assault if made. Special care will be taken to avoid being deceived by false attacks; and the assault, if made, will be met as previously described (par. 6). If the attack is repulsed, an offensive return may be made by the general reserve, assisted, when necessary, by the local reserves of the front of attack; but the garrisons of the permanent works should not be withdrawn from them for this purpose, as it is always possible that they may be needed to protect the works and cover a retreat. If the assault succeeds, the defenders will retire to their positions in rear, from which the strongest possible fire will be directed upon the pursuing troops and upon the captured position to render its possession difficult or impossible. If the assailants are driven off, the position is immediately reoccupied by the defence. =108.= =Defence during the Second Period of the Siege.=--The point of attack having been definitely determined by the preliminary steps of the attack in opening the parallels and establishing the batteries, the besieged will at once proceed to mount extra guns and reinforce the troops upon the threatened fronts. He will keep his outposts or sentinels during this and the subsequent periods as far to the front as possible, to prevent surprises and to keep out reconnoitring parties spies, etc., etc. From observations previously established, he will locate at the earliest possible moment the batteries, etc., of the attack, and will prevent their completion and arming by the use of shells and case-shot charged with high explosives, fired from howitzers and mortars. He will use his long guns for counter-battering those of the besieger, and generally for direct fire upon exposed targets. By taking the initiative he may frequently obtain the upper hand in the artillery duel, and possibly be able to prepare the way for strong sorties, and the destruction of the besieger’s works. In any case he must at this stage develop the full fire of his guns and work them to their maximum value. If, however, the superiority of the artillery of the attack is pronounced, and it becomes impracticable to serve any battery advantageously, it will be better to dismount its guns and remount them in other positions, as indicated in the preceding paragraph (par. 106). All efforts will be made to prevent the construction of the parallels and approaches, their positions being discovered by the use of the search and other lights, and the work upon them retarded by direct and curved fire. For the latter light rifled mortars promise to be very effective.[7] The trenches connecting the detached and intermediate works will be strengthened, and counter-approaches will when practicable be driven out to afford positions for enfilading the approaches. The field and machine guns will be held in constant readiness for use, and will be brought into action at every favorable opportunity; but will be withdrawn and placed under cover previously prepared so soon as the fire upon them becomes too severe to be endured. Meanwhile a new position in rear, with its flanks supported upon the adjacent detached works, will be selected and made ready for defence in case the front line is taken. The general reserve will be used for offensive movements, which are made whenever favorable opportunities arise, particularly in making counter-attacks after unsuccessful assaults. =109.= =Defence during the Third Period.=--The defence of the detached works of an intrenched camp during the Third Period will be conducted, so far as the general reserve is concerned, in very much the same manner as during the Second Period; but in the immediate defence of the detached work itself, owing to the close approach of the besieger, its character will change. The artillery except the field and machine guns will be silenced, and the latter will usually be only available for defending the ditches and for repelling assaults. Light guns will, however, be held in readiness for temporary use when practicable. The outposts will of necessity be drawn in and replaced by a chain of sentinels along the parapets of the covered way or the main parapet, who will pick off the besiegers at every possible chance, and will be reinforced by the rest of the garrison when an assault is imminent. All flanking defences will be kept in as good condition as possible, and in readiness to prevent the crossing of the ditch, or to repulse an assault. Grenades and shells will be kept in readiness to roll into the ditch, the breaches will be obstructed and mined if practicable, counter-mines will be brought into play, and all other possible measures taken to retard the approach of the besieger to the breach and to repel his assaults. When, however, the work is reduced to such a state as to make its defence hopeless, it should not be held at the expense of great losses to the defence, unless the besieger’s works can be considerably delayed by doing so. When the position consists of an enceinte with ordinary outworks, the investment during the Third Period of the siege will be closer, the opportunities for using the general reserve will usually disappear, and its troops will be merged with those of the general defence. When, in this case, the place is to be defended to the last, all measures will be taken for the defence of the breach; and after this is carried, for the final defence of the inner retrenchments or keeps. The tactical handling of the garrison for this purpose is in accordance with the principles already laid down (par. 6, and Art of War, pars. 282-84.) The sorties recommended during a siege are, when made by the general reserve and in large bodies, usually carried out by moving the troops from the collateral works upon the flanks of the besieger’s works. In the close attack, however, they may be made by small parties moving to the front from the nearest outpost or salient. The object in all cases is the same--to destroy the enemy’s works, delay his advance, and inflict upon him all possible loss. THE CAPITULATION. =110.= Should the defensive policy of the state not require a place to be held to extremity, the governor must be fully informed of the fact, and the extent of the defence and the conditions of capitulation must be fully understood by him before the investment. As a rule, however, no excuse will be received for the surrender of a place until every means of defence is exhausted, and further resistance is not only hopeless, but impossible, the only rule which can guide the governor being that “one additional day of defence may be of incalculable benefit to his country.” The old rule, copied from the French, but no longer observed by them, requires the defence to sustain at least one assault on a practicable breach in the body of the place. Within recent years, in civilized warfare, no cases have occurred in which such assaults have been made, the places having been reduced by the more distant attack; but assuming such an assault to be repulsed, it will not justify the surrender of the place so long as a possibility of repulsing similar assaults exists. The garrison must withstand all attacks of whatever nature to the last extremity, and continue the defence up to the full requirements of duty and honor--surrendering only when nothing else is possible. JOURNAL OF THE DEFENCE. =111.= =A Journal of the Defence=, entirely similar to that of the attack, will be kept by the besieged for use by the War Department in case of a successful defence. Nothing should be entered in the journal which might be of special value to the besieger in case the place is taken, but a separate journal of such matter should be kept in cipher, or should be destroyed before the surrender of the place. CHAPTER VII. PARKS AND DEPOTS, SHELTERS AND HUTS, KITCHENS, OVENS, SINKS, LATRINES, WATER-SUPPLY, ETC. PARKS AND DEPOTS. =112.= =The Engineer and Artillery Parks and Depots= are located and arranged for security against the artillery-fire and the attack, by surprise or otherwise, of the defence, and also for facility in receiving, storing, and distributing materials and supplies. The first condition is fulfilled by placing them at a safe distance, concealing them from the view of the defence if possible, and guarding them against attack, and the access of incendiaries, etc., by strict application of ordinary defensive tactics, and a most thorough system of interior guards. Powder depots, trains, etc., especially are guarded against the access of all unauthorized persons. The second condition, when railroad communication is used, is satisfied by making the park conform to the best-planned railroad terminals and freight-yards. A type arrangement is given in Plate IX, Fig. 85, in which switches from the main line give access to as many side-tracks, _a_, _b_, _c_, _d_, etc., and spurs, 1, 2, 3, etc., as may be needed. When practicable, these sidings should connect at each end with the main line in order to afford free ingress and egress from both directions. They should be placed at such distances apart as to allow loading-platforms and the desired room for sheds, piles of materials, etc., between them; large areas being left for light, and small for heavy, materials. The spurs, 1, 2, 3, etc., should preferably be short; but if long, should be connected by switches. A Υ, as indicated, is frequently convenient for reversing complete trains without uncoupling the cars, and is indispensable when a turn-table is not available. When the powder-depot is separated from the main park it is better to reach it by a special track branching from the main line at some distance from the park, so that the ammunition-trains will not pass through or near the latter. The sketch given is proposed as a type only, since the park may occupy one or both sides of the main line, be long and narrow, short and broad, regular or irregular in outline, as may best conform to the ground available. Standard-gauge roads will, when practicable, be laid between the main park and the smaller depots. When this is not feasible, narrow-gauge tram-roads will be used instead, and will also connect the smaller depots with the trenches and batteries. The portable tramways used by contractors are well fitted for use in the trenches. When the park is located upon navigable water a number of piers and wharves are occupied. They should be provided with derricks or cranes, and tracks and cars upon which materials may be loaded directly from the ships. The park may then be arranged on the general plan above indicated. The switches are so arranged as to allow empty cars to return to the wharves on a track different from that used by the loaded ones. In storing materials and supplies in the park care must be taken to place each class by itself, and to so pile them that they can be readily inventoried and inspected, and be removed or replaced without disturbing other piles. This requires the piles to be arranged in regular order, with unobstructed passages between them, and prohibits piling articles of different kinds or sizes on top of each other. SHELTERS AND HUTS. =113.= In a regular siege, the besieging army will, as a regular rule, eventually be provided with tents or portable huts for shelter; but before this is accomplished much suffering and consequent disease may result from exposure, which could be avoided by the construction of temporary shelters, huts, and screens from materials available for this purpose. In severe winter weather tents and thin wooden huts do not afford sufficient protection, and it may be necessary to substitute for them others with walls of logs, sods, sand-bags, adobe, or other materials, or even huts partly or entirely sunk into the earth. The greatest care must be exercised in enforcing proper ventilation and cleanliness in huts of this class. If this is not done serious fevers and other camp diseases are almost sure to occur. (Art of War, Art. 352-3.) The figures given (Plate IX, Figs. 86-94) have been selected from a great many examples to serve as suggestions. They may be modified or combined, as circumstances require. Their construction is evident from the figures, and requires no description. Ditches surrounding the huts are made to carry off rain-water. Heavy roofs are supported by poles set up inside the hut as needed. Fireplaces are dug in the sides of the excavation, or are built up of sods, clay, etc. It is better to make two, as shown, to obtain a good draught in any wind. Chimneys are made of sods or of sticks plastered with clay, unless drain-tiles, tin cans, or other suitable materials can be found. Great care must be taken to prevent their setting the roof on fire. In many cases water-proof roofing felts and papers may be obtained and used for roofs, etc., in huts and shelters. The lumber from packing-boxes, tin from canned vegetables, and wire from baled forage may frequently be utilized for doors, chimneys, ties, etc. Straw mats for mattresses, etc., are economical in the use of straw and conduce to cleanliness, as they can be easily taken up and replaced. The method of making them is shown in Pl. IX, Fig. 95. When twine is not at hand, they may be woven of straw rope. They, as well as all other bedding, should be taken out and sunned every dry day. Ordinary hurdles laid upon the ground or raised a few inches above it protect the blankets, etc., from the moisture of the earth. It cannot be too strongly impressed upon officers, that all devices of the kind above indicated, which add to the comfort of the men, add also to their health, morale, and efficiency. KITCHENS AND OVENS. =114.= In our service a company will usually have a camp-cooking outfit sufficient for its needs, and generally of good pattern; but these are not always on hand when needed, and small detachments are frequently deprived of them for days or weeks. In ordinary soil, kitchens, and in a clay soil ovens, can be constructed, which, with a few kettles and cans, will enable the men to prepare for themselves fairly good meals without unnecessary waste of fuel. A few of these are figured in Pls. IX, X, Figs. 96-103. The banks of the trench shown in Fig. 96 afford support for cross-bars, and protect the fire from the wind. The type shown in Figs. 97, 102, 103 take the place of a stove, require but little fuel, and secure a steady heat. To obtain a good draught they should be so built that the wind blows toward the chimney. For this purpose they may radiate from a central chimney. (The flues of those not in use may be temporarily stopped up with sods.) The arch of the oven shown in Pl. X, Fgs. 98-101, may be built over a piece of sheet iron if it can be obtained; if not, over a hurdle well smeared with clay. A slow fire will, under favorable conditions, dry and bake the clay arch so that it will stand after the brushwood of the hurdle is burned out. They may then be heated and used for baking. LATRINES, SINKS, ETC. =115.= Latrines and sinks for the reception of garbage, etc., are objects of the greatest importance in all camps, temporary or permanent; and, unless properly made and cared for, they speedily make their presence known, and become a most prolific source of discomfort and disease. For permanent camps liable to be occupied for a long time special arrangements for the disinfection, removal, and destruction of garbage and excreta must be made. For temporary camps it will suffice to provide pits with suitable conveniences and screens; covering with a thin layer of the excavated earth all deposited garbage and excreta before they become offensive. When, as is sometimes the case, these pits cannot be kept free from water, it may be necessary to use in addition lime, copperas, carbolic acid, or other chemical disinfectants and deodorizers. The ordinary constructions used in temporary camps are shown in Pl. X, Figs. 104-107. Separate latrines for officers are constructed and screened. The seat shown in Fig. 107, when one can be obtained, adds much to their comfort. In more permanent camps the latrines may be roofed and screened with canvas or boards, and board seats be provided for the men. Uninclosed sinks and latrines should have earthen banks all around them, to indicate their position and to prevent men walking into them at night. Upon abandoning a camp all sinks and latrines are to be disinfected and filled up. WATER-SUPPLY. =116.= The problem of obtaining a sufficient and wholesome water-supply for a besieging army is usually one difficult of solution. The precautions which are necessary in ordinary camps (Art. of War, 352 and 358) become of still greater importance in this case, owing to the choice of the source of supply being limited to those which are not controlled by the besieged, and to the constantly increasing danger of pollution of all ground waters by the bodies of the dead men and animals and the refuse and filth of the camps. The evils arising from these sources may be largely or entirely removed by boiling the drinking-water, and the disagreeable tastes and smells may be removed by filtering through good filters. It is very difficult, however, to compel the men to boil the water, or to drink it after it is boiled, unless it is properly aerated and filtered. All available measures should, therefore, be adopted to supply them with wholesome water. The results of the most recent researches show that properly conducted _intermittent filtration_ with sand-filters will render a polluted water almost if not entirely safe. (See reports of Massachusetts State Board of Health on Purification of Sewage and Water, 1890.) And the analysis of water sterilized by a steam-jet at the Columbian Exposition in Chicago, 1893, gives reason to believe that this process may be very effective in removing disease germs. (See report of Allen Hazen, Chemist, Department of Water-supply, published in _Engineering News_, March 29, 1894.) In camps of some permanence one or both of these processes may be well worth applying. Small filters for limited amounts of water may be bought in the market, or may be improvised and set up for officers or company messes. Figs. 108-110, Pl. X, are given as suggestions; they serve as strainers in any case. If used intermittently they _may_ have a high sanitary value, and if made up partly of either animal or wood charcoal they remove more or less completely any offensive taste or odor which water may have. Security, however, requires doubtful water to be boiled. In all cases arrangements should be made to protect the water from surface pollution, for convenient access for the men, and for watering horses. (See the following books, treating on Military Hygiene in Camp and Garrison: Parker’s Practical Hygiene; Traité d’Hygiène Militaire, Morache; Manuel d’Hygiène militaire, Viry; Military Hygiene, Woodhull; the Soldier’s Pocket-book, Wolseley; etc., etc.) PART II. _MILITARY MINING, BLASTING, AND DEMOLITION._ CHAPTER I. NOMENCLATURE AND THEORY. =1.= =Military Mining= includes all the operations necessary for placing charges of explosive underground and exploding them at the time desired, for the purpose of destroying the men, materials, or works in their vicinity, or for breaking up the surface of the ground either to advance or retard the operations of a siege. The excavation for receiving the _charge_ is called the _chamber_. The approaches leading to the chamber when horizontal or somewhat inclined are called _galleries_, and when vertical are known as _shafts_. When very steep they are sometimes called _slopes_. The charge, chamber, and approaches taken together constitute a _mine_. The pit formed by the explosion is called the _crater_. When the ground is homogeneous and its surface horizontal, the intersection of its surface by the crater is approximately a circle, the radius of which is called the _crater radius_, _AB_, Pl. XI, Fig. 1. The right line joining the centre of the charge with the nearest point of the surface toward which the explosion will take place, generally the surface of the ground, is called the _line of least resistance_ (written generally L. L. R.), _C B_, Pl. XI, Fig. 1. A right line from the centre of the charge to the edge of the crater is called the _radius of explosion_, _C D_, Pl. XI, Fig. 1. The distance from the centre of the charge at which an ordinary mining gallery will be broken in by the explosion is called the _radius of rupture_, _C L_, Pl. XI, Fig. 3. The radius of rupture varies in length with its inclination to the horizontal. Craters whose _diameters_ are once, twice, etc., their lines of least resistance are called _one-lined_, _two-lined_, etc., craters. Mines in which the L. L. R. is equal to the _crater radius_ are called _common mines_. (Their craters are _two-lined_.) Those in which the crater radius exceeds the L. L. R. are called _overcharged mines_ or _globes of compression_; when it is less, they are _undercharged mines_; and when the charge is so small that no exterior crater is formed, they are known as _camouflets_. =2.= In the explosion of military mines on land it may safely be assumed that the circumstances of combustion of the charge when fired are such that the energy developed is directly proportional to the charge. A portion of this energy is generally lost by the escape of the compressed gases into the air, by the heat given up to the surrounding media, and by the transmission of earth-waves or shock; the remainder and greater part, however, is expended in rupturing the case containing the charge, compressing the soil in its immediate vicinity, separating that lifted up from that forming the sides of the crater, breaking up the portion thrown out into large or small fragments, projecting them to a greater or less distance, and disintegrating the soil around the crater to a distance which varies with the soil and with the quantity and character of the explosive used. As the proportional part of the energy expended in each of the effects above named cannot be determined in any particular case, and as each case differs in some respect from every other, it is manifestly impossible to express in any mathematical formula a rule for determining the exact amount of explosive required for any particular mine. From the results of long experience, however, engineers have concluded that computations sufficiently exact for practical purposes can be made upon the hypothesis that _for common mines and those approximating closely to them in form_, the volumes of the craters are directly proportional to the charges used. =3.= In order to apply this rule in practice the volumes of craters formed by known charges must be measured; but since the soil in the immediate vicinity of the crater is more or less disintegrated, and the crater itself is partly filled up by the material which falls back into it, the outlines of the original crater cannot usually be recognized or its exact geometrical figure be determined. Besides, the craters formed under circumstances seemingly identical differ more or less among themselves. For convenience in computation, however, several simple geometrical figures have been assumed as giving with sufficient accuracy the form of the crater of a common mine. See Pl. XI, Fig. 1. Among these Vauban assumed a cone, _ACD_, with its vertex at the centre of the charge; Valière a paraboloid of revolution, _AHD_, with its focus at the centre of the charge; Müller truncated this paraboloid by a horizontal plane through its focus; while Gumpertz and Lebrun adopted the form in common use at their time, and which has been generally accepted since, viz., a frustum of a cone, _AEFD_, the smaller base of which passes through the centre of the charge and has a radius, _EC_, equal to one-half the crater radius, _AB_ (or one-half L. L. R., _CB_). The volumes of these figures are as follows: Vauban’s cone 1.05 (L. L. R.)^3, Valière’s paraboloid 1.90 (L. L. R.)^3, Müller’s truncated paraboloid 1.84 (L. L. R.)^3, The frustum of a cone 1.83 (L. L. R.)^3 = nearly (11/6)(L. L R.)^3. The cone of Vauban (lately assumed also by Höfer) was abandoned as unsatisfactory, because it did not conform to the craters produced, and, as treated by Höfer, because the charges computed by its use were found to be too small (an error in the wrong direction). The paraboloid of Valière or Müller would seem to conform more nearly to the actual shape assumed by the crater; but it will be observed that the volume of the latter is sensibly the same as that of the truncated cone, and as the volume of earth thrown out is the quantity to be considered, the truncated cone will be assumed as the measure for it. =4.= The principle that “the volumes of the craters are proportional to the charges used” is the general statement of the _miner’s rule_. Assume _C_ and _C´_ to represent the charges of two mines whose volumes are _V_ and _V´_, lines of least resistance _l_ and _l´_, and crater radii _r_ and _r´_. Assume also that the craters are frustums of cones, the radii of whose larger bases are twice those of the smaller. Then _C_ : _C´_ :: _V_ : _V´_ :: (11/6)(_lr_^2) : (11/6)(_l´r_´^2), or _C´_ = _C_ (_V´_/_V_) = _C_[(11/6)(_l´r_´^2)/(11/6)(_lr_^2)] = _C_[(_l´r´_^2)/(_lr_^2)] ... (1) Equation (1) is applicable to _mines in which r does not differ materially from l or r´ from l´_. From an experimental mine giving a crater of this general type the relations between _C_, _l_, and _r_ may be determined, and assuming any two of the quantities _C´_, _l´_, and _r´_ for a mine with a crater nearly similar in form, the other may be found from eq. (1). When _l_ = _r_ and _l´_ = _r´_, we have _C_ : _C´_ : :(11/6)_l_ : (11/6)_l_´^3, and _C´_ = _C_[(11/6)(_l_´^3)/(11/6)(_l_^3)] = _C_[(_l_´^3)/(_l_^3)] (2) Equation (2) is applicable to common mines, and shows that _in common mines the charge varies as the cube of the line of least resistance_. Assuming _C__{´}_ as the charge which will produce a crater with a volume of unity, equations (1) and (2) become, by omitting the primes from _l_ and _r_, _C_ = _C__{´}_(11/6)_lr_^2, (3) and _C_ = _C__{´}_(11/6)_l_^3 (4) Equation (4) gives the rule for determining the charge for common mines whose L. L. R. is given, viz.: _Multiply 11/6, the cube of the line of least resistance in yards, by the quantity of explosive required to throw out one cubic yard_. The latter quantity is determined by experiment. A similar rule may be written out from eq. (3) for mines differing but little from common mines. =5.= The quantity of gunpowder required to throw out a cubic yard of material has been calculated from a great number of mines fired in different kinds of soil. The following table gives the quantities required according to Lebrun and Macaulay, respectively the French and English authorities on the subject:[8] TABLE A. Number. Description of Earth, Rock, or Weight per Charge, Charge, Proportional Masonry. cubic foot. Gumpertz Macaulay. value and Lebrun. of charge. lbs. lb. oz. lb. oz. 1 Light sandy earth (_common earth, 85 1.8 1.13 1.12 Lebrun_) 2 Hard sand 111 1.10¾ 2.0 1.25 3 Fat earth mixed with sand and gravel (_common earth, Macaulay_) 116 1.5⅓ 1.10 1.00 4 Wet sand 118 1.12 2.2 1.30 5 Earth mixed with stones 118 1.14 2.4 1.40 6 Clay mixed with tufa 124 2.1 2.8 1.55 7 Fat earth mixed with pebbles 143 2.4 2.12 1.69 8 Rock 143 3.0 3.10 2.25 9 New or old moist brickwork or masonry 2.2 1.30 10 Inferior brickwork or masonry 2.11 1.66 11 Good, new ditto 3.10 2.25 12 Good, old ditto 4.1 2.50 13 Roman ditto, or other equally good in warm climates 4.11 2.90 =6.= For _common mines_ in _ordinary earth_ a convenient rule, very generally used, and which gives results nearly the same as those deduced from the table, is: _The charge of gunpowder in pounds is equal to one tenth the cube of the line of least resistance in feet_, or _C_ lbs. = (1/10)_l_^3 ft. (5) OVERCHARGED AND UNDERCHARGED MINES. =7. For overcharged and undercharged mines= in which the L. R. R. and crater radius differ materially in length the results deduced from the preceding equations are not applicable. For such mines the following equations, due to Gumpertz and Lebrun, are in common use, viz.: For an overcharged mine, _C_ = _C__{´}_(11/6)[_l_ + (7/8)(_r_ - _l_)]^3. (6) For an undercharged mine, _C_ = _C__{´}_(11/6)[_l_ + (7/8)(_l_ - _r_)]^3. (7) In which _C_ = charge of explosive in pounds, _l_ = L. L. R. in yards, _r_ = crater radius in yards, _C_{´}_ = amount of explosive in pounds necessary to throw out one cubic yard of earth in a common mine in the same soil. These formulæ are deduced as follows, viz.: It was found by experiments made independently by Belidor and Marescot that 3660 lbs. of powder in a mine with L. L. R. equal to 4 yards gave a crater with a radius of 12 yards in earth requiring for a common mine 1½ lbs. of powder per cubic yard. The charge for a common mine in the same soil with L. L. R. equal 4 yards is (11/6)(4 yds.)^3 × (1½) = 176 lbs. Representing by _l_ the L. L. R. for a common mine requiring a charge of 3660 lbs., since the charges of common mines are proportional to the cubes of their lines of least resistance, we have 176 : 3660 :: 4^3 : _l_^3 = 1330.8, whence _l_ = 11^_y_; 11^3 = 1331. To find from these data the relations between charges for overcharged mines, construct Figs. 2 and 2_a_, (Pl. XI.) Fig. (2) gives mines with crater radii of 4^_y_ and 12^_y_ and a common L. L. R. of 4^_y_. Divide the distance between _A_ and _B_ into four equal parts, and assume the points of division as the extremities of the crater radii of overcharged mines, each of which exceeds the one next smaller by (¼)_AB_, and all corresponding to a L. L. R. of 4^_y_. Fig. (2_a_) gives common mines with lines of least resistance of 4^_y_ and 11^_y_. Divide the distance _A´B´_ also into four equal parts, and assume the points of division as the extremities of the crater radii of common mines each of which exceeds the one next smaller by (¼)_A´B´_. Since the charges for the common mines whose lines of least resistance are respectively 4^_y_ and 11^_y_ are identical with those of the overcharged mines whose crater radii are 4^_y_ and 12^_y_ respectively, it is assumed that the charges for the intermediate common mines are the same as would be required to produce the corresponding intermediate overcharged mines. The increment of the crater radius and line of least resistance of any one of these common mines is equal to 7/8 the increment of the crater radius of the corresponding overcharged mine; consequently the charge which gives an overcharged mine whose L. L. R. and crater radius are _l_´ and _r_´, respectively, will produce a common mine whose L. L. R. _l_ will be given by the equation _l_ = _l_´ + (7/8)(_r_´ - _l_´). (_a_) Since the charge for a common mine is obtained from equation (4), _C_ = _C__{1}(11/6)_l_^3, the charge for the overcharged mine will be _C_ = _C_{1}(11/6)[_l_´ + (7/8)(_r_´ - _l_´]^3, as above. For ordinary earth and gunpowder, when L. L. R. is measured in feet, eqs. (6) and (7) become, respectively: For an overcharged mine, _C_ = (1/10)[_l_ + (7/8)(_r_ - _l_)]^3 (6´) For an undercharged mine, _C_ = (1/10)[_l_ - (7/8)(_l_ - _r_)]^3 (7´) =8.= Giving to _l_ the same value in equations (4), (6), and (7), we have _C_´ = _C_((7/8)[_r_/_l_] + (1/8))^3, (8) In which _C_ = charge for _common mine_ with L. L. R. and crater radius = _l_. _C_´ = charge for _over_ or _undercharged mine_ with L. L. R. = _l_ and crater radius _r_. Equations (6), (7), and (8) having been deduced from the relations existing between _C_, _l_, and _r_ for mines varying from common mines up to those in which _r_ = 3_l_ may safely be used for _overcharged_ mines up to this limit.[9] In their applications to _undercharged_ mines they become uncertain when _r_ = (½)_l_; and when _r_ = (⅜)_l_ the computed charge generally produces a camouflet. These computed charges are: for _r_ = (½)_l_, _C_´ = 0.1779_C_; for _r_ = (⅜)_l_, _C_´ = O.1636_C_. A rule of the French engineers states that a charge which will produce a common mine with L. L. R. = _l_ will produce a camouflet if the L. L. R. is increased to (7/4)_l_. At this depth _C_´ = 0.187_C_, and the formula gives a crater radius of 25/49. As a safe “rule of thumb,” we may assume that _a charge which will give a common mine with L. L. R. = l_ will give a camouflet with L. L. R. = 2_l_ (_r_´ from formula = (3/7)_l_). Conversely, _a camouflet will be produced by ⅛ of the charge which will produce a common mine_. =9. Radius of Rupture.=--The determination of the _radius of rupture_ is an important consideration in underground warfare, since, when it is known, miners may so place their chambers as to break in the galleries of the enemy without injuring their own. As different mining galleries, however, differ from each other so much in strength to resist crushing, and as the cost of an exhaustive series of experiments to determine their relative strength would be so great both in time and money, but little well-established data exist upon which to found a rule for determining the radius of rupture. =10.= The rule deduced by Gumpertz and Lebrun, however, from the material available at their time corresponds very nearly with the results of later experiments and observations, and is generally admitted as sufficiently near correct for practical use. This rule is based upon the theory that the surface of rupture is an oblate spheroid, (Pl. XI, Fig. 3), with its axis of revolution vertical and its centre at the centre of the charge; the intersection with the surface of the ground _AD_ coinciding with the edge of the crater. The ratio between the semi-transverse axis _CF_ and the semi-conjugate axis _CH_ of the generating ellipse of this assumed spheroid is the same as that between the radius of explosion _CD_ and L. L. R., _CK_. The rule is, that _the radius of rupture in any direction is equal the corresponding radius of this spheroid_. From the conditions assumed the following values of the semi-transverse and semi-conjugate axes _h_ and _v_ (which are the horizontal and vertical radii of rupture) are obtained, viz.:[10] _h_ = _l_√(1 + 2(_r_/_l_)^2); _v_ = _l_√[(1 + 2(_r_/_l_)^2)/(1 + (_r_/_l_)^2)]. For common mines these formulas give: _h_ = 1.732_l_ = (7/4)_l_ = (7/4)_r_; _v_ = 1.225_l_ = (5/4)_l_ = (5/4)_r_. For six-line craters, _h_ = 4.358_l_ = (35/8)_l_ = (3/2)_r_; _v_ = 1.378_l_ = (11/8)_l_ = (1/2)_r_. =11.= The English authorities adopt the value of (7/4)_l__{´} for the horizontal and _l__{´} √(2) = 1.41421 _l__{´} = (7/5)_l__{´} for the vertical radius of rupture of all classes of mines. In which _l__{´} = L. L. R. of an equivalent common mine = _l_ + (7/8)(_r_-_l_), etc. Some later experiments at Chatham have given _v_ = (5/3)_l_ for a 4-lined crater; _v_ = 2_l_ for a 5-lined crater; and _v_ = (5/2)_l_ for a 7½-lined crater. =12.= There are other good reasons for believing that Lebrun’s value for the vertical radius is too small; but as its use leads to increasing the charges designed to produce crushing effects, the error, if it exists, is in the right direction, and justifies the use of the formula until more exact data are available. EXPLOSIVES. =13.= No military mining operations of note have been carried on since the introduction of dynamite and other high explosives; consequently our knowledge of their value for work of this kind rests entirely upon the results obtained from experimental mines. Unfortunately but few experiments seem to have been made, and the published results of these are very meagre. =14.= Two mines fired at Krems in 1873 with L. L. R. of 12 ft. in earth weighing 100 lbs. per cubic foot and charged, one with 173 lbs. gunpowder, the other with 58 lbs. dynamite (kind not stated), gave crater radii, respectively, of 12.75 and 10.25 feet. Lebrun’s formulas applied to these give to gunpowder and dynamite the ratio 1 : 1.688. Two powder-mines and one dynamite-mine, each of 12 ft. L. L. R., were fired at Willet’s Point in 1878. The powder-mines were each charged with 200 lbs. cannon-powder and the dynamite mine with 82 lbs. dynamite No. 1. No. 1 powder-mine gave a crater radius of 15½ ft. No. 2 powder-mine gave a crater radius of 15¼ ft., or a mean of 15⅜ ft. The dynamite-mine gave a crater radius of 14½ ft. The relative values of cannon powder and dynamite resulting from the application of the same formulas to these mines is 1 : 1.997.[11] =15. Choice of Explosive.=--From these experimental mines it may be concluded that for forming craters in ordinary earth dynamite is not quite so efficient as double its weight of good gunpowder. For breaking up hard rock, blowing up strong masonry, and especially in demolitions where tamping is usually defective, this ratio does not hold; but the relative effect of the high explosive increases continually with the lack of tamping and the intensity of the local blow desired, until a point is reached at which the effect of gunpowder is almost imperceptible, while the high explosive does efficient work. This property of the high explosives renders them extremely valuable for use in hasty demolitions, such as blowing up palisades or barriers, destroying guns, etc., etc. Owing to their varying values in different conditions the choice of explosive to be used in any particular case must evidently depend upon the circumstances attending it. In underground explosions both gunpowder and high explosives give out noxious gases which penetrate the soil, and which entering a gallery in sufficient quantity would suffocate the miners. Of these gases the carbonic oxide given off by some of the high explosives is probably the most dangerous to human life, and if mixed with the proper proportion of air forms an explosive mixture, resembling in this respect the fire-damp of the coal-mines. Whether in practical mining operations it would ever be retained in the soil in such quantities as to produce this effect remains to be seen. Some of the high explosives, on the other hand, seem to produce relatively small quantities of noxious gases. The gases produced by gunpowder, while suffocating in their nature, have the advantage of always making their presence known by their odor. =16.= For use in overcharged mines designed to break in the enemy’s galleries, the high explosives, from the violent character of their explosion and from the phenomena exhibited in submarine mining, promise to give relatively greater radii of rupture than gunpowder; but sufficient data are not available to state this positively.[12] =17.= Beside the considerations above stated, which refer to the effects produced by the explosive when fired, there are others equally important relating to the safety and facility with which the explosive may be transported, handled, and placed in the mines. The latter will frequently have greater weight than the former in determining the explosive to be used in any particular case which may arise in the practical operations of mining. Of the latter considerations some of the most important in deciding whether to use gunpowder or high explosives are the following, viz.: Gunpowder is easily obtained, and most enlisted men are more or less familiar with its properties. It explodes when ignited by fire. It does not ordinarily explode when struck by a bullet. It is injured by moisture and destroyed by thorough wetting. It is not affected by ordinary changes of temperature. It requires thorough tamping to produce good effects. Many high explosives are not injured by moisture, and some are unaffected by total immersion in water. They generally burn without detonation if ignited by flame. Some of them do not explode when struck by a bullet. The more sensitive ones do. The properties of some of them are materially changed by freezing. On account of their greater strength, the same effects may be produced by smaller charges, requiring smaller chambers and cases. By reason of the violence of their action they produce good results even if imperfectly tamped. The last two considerations, together with the possibility of using them in wet places without protection against moisture, lessen greatly the time required to excavate, charge, and tamp a mine, and may frequently enable the one using them to anticipate an enemy using gunpowder and thus secure success, when the use of gunpowder would reverse the situation. In mining operations and in expert hands the high explosives, upon the whole, seem to cause fewer accidents than gunpowder. CHAPTER II. PRACTICAL OPERATIONS AND DETAILS. =18. Tools and Appliances.=--The different operations of mining are carried on by the use of picks, shovels, bars, saws, axes, hammers (large and small), chisels, wheel and hand barrows, windlasses, ropes, wooden or leather buckets, gauge-sticks, mason’s levels (Pl. XI, Fig. 4), plumb-lines, candles, closed lanterns, tin pipes, rubber and canvas hose, canvas, nails, etc., etc., of the kinds in common use; and the following special tools and appliances, viz.: The _Miner’s Pick_. Smaller and lighter than the common pick. Neither its head nor its handle exceeds 2 feet in length. The _Miner’s Shovel_. Similar in shape to a common shovel, but not exceeding 2 feet in length. The _Push Pick_ (Pl. XI, Fig 5), which has a lance-shaped blade about 3½ in. wide and 6 in. long attached to a handle about 2 feet long. The _Field Level_ (Pl. XI, Fig 6), which consists of three strips of wood about 2" × ½", arranged as shown. The strip _A_ is 4' between centres of pins; _B_ and _C_ are 2', 9-15/16"; the angle at a = 90°. A spirit-level is inserted in piece _C_, and a plumb-line attached as shown. The markings on _A_ are used for gentle slopes, those on _B_ for steep ones. The other sides of _B_ and _C_ are divided into degrees of arc, the centre being at the middle point of the outside edge of _A_. The _Slope Block_, which is a wooden cube used in connection with a mason’s level for fixing slopes. _Angle Templets_ (Pl. XI, Fig. 7), making a definite angle, used in laying out galleries. The _Miner’s Truck or Car_. A small, four-wheeled wagon with fixed axles and very short wheel-base; exterior dimensions about 20" wide, 18" to 20" high, and 30" long. Used for carrying earth through galleries, and usually hoisted up the shaft and dumped outside, replacing the buckets used in sinking the shaft. The _Miner’s Bellows_ (Pl. XI, Fig. 8). A leather bag with wooden top and bottom, provided with inlet and outlet valves, from the latter of which the air is led off in pipes or hose. In using the bellows the miner stands upon the lower handles and works the bellows with his hands by the upper ones. This is frequently replaced by a common blacksmith’s bellows or the rotary blower from a portable forge; and sometimes by an improvised air-pump, consisting of a large open cask filled with water and another smaller one, with one head removed and the other provided with outlet and inlet valves and an air-tube, inverted over the large cask, supported by a spring-pole and worked up and down by hand in the water of the lower cask. The _Miner’s Candlestick_ (Pl. XI, Fig. 9), which holds a candle, and may be driven into the side or bottom of a gallery. _Miner’s Lamps_ (Pl. XI, Fig. 10), can be used only when the ventilation is good, as they give off more smoke than candles. When an electric-light plant is available, incandescent lamps will be used for mining. _Earth Augers_, similar to those used for boring post-holes, but of different diameters, are sometimes used for placing camouflets. Their shanks are made in short lengths, which can be joined together to allow of boring a deep hole from a narrow shaft or gallery. GALLERIES AND SHAFTS. =19. The Dimensions of Galleries and Shafts= are determined by the use to be made of them, the necessity of ventilation, and the minimum space in which a man can work. They are usually about as follows, viz.: Height, Width, feet. feet. 1. Great or grand galleries 6 7 2. Common galleries 6 3½ 3. Half galleries 4½ 3 4. Branches 3½ 2½ 5. Small branches (_rameaux de combat_). 2½ 2 Shafts vary in size--from the smallest in which a man can work (about 2' × 4'), to any size that may be required, seldom exceeding 10' × 10'. Great galleries are used for descent into a ditch, and when it is wished to pass cannon through them.[13] Common galleries are used for descent into a ditch, and for communications. Troops can pass through them “by twos.” Half galleries answer for general purposes of attack. They allow the miner to work freely in different positions without being cramped, but are small enough to admit of rapid driving. Branches and small branches are driven out from the galleries to the mine-chambers, etc. They can be driven rapidly for short distances (10 to 20 feet); but when of greater length the earth is removed from them with difficulty, they are not easily ventilated, and are too small for use as communications. =20. Shaft and Gallery Linings.=--In very firm soil it is sometimes practicable to drive small shafts and galleries short distances without lining them; but if these are to stand for any length of time, there is always danger of their falling in, particularly if shaken by the explosion of mines in their vicinity. When it is considered safe to use them, however, the shafts should be elliptical in plan, and the roofs of the galleries should be pointed arches. As a rule, however, both shafts and galleries should be lined. Those which are permanent in their character--as the main galleries of the countermines of a permanent work--are lined with masonry. Masonry linings may be of brick, stone, or concrete walls and arches. The smaller galleries constructed during a siege, and all the shafts and galleries of the attack, are lined with wood. Wooden linings are of two general types, known as _cases_, and _frames and sheeting_. =21.= _Cases_ (Pl. XI, Figs. 11 and 12) are made of plank, from 6" to 12" wide, each case consisting of a cap-sill, a ground-sill, and two stanchions. The cap and ground-sills are cut to a length equal to the clear width of the shaft or gallery plus twice the thickness of the stanchions; a rectangular notch is cut in each end to receive a corresponding tenon cut on the stanchion. The length of the stanchions between shoulders is equal to the clear length of the shaft or height of the gallery. The length of the tenons is generally equal to the thickness of the cap and ground sill (usually 2´´), and their width about three inches. Notches are cut in the sides of all the pieces of the case, as shown in the figure, for convenience in handling them. In grand galleries the tenons at the top of the stanchions are usually shorter than the thickness of the cap-sill, and those at the bottom, as well as the mortises in the ground-sill, are omitted. The stanchions are kept from collapsing by blocks nailed to the ground-sills. These blocks are 2" thick, and wide enough (about 9´´) to so guide the wheels of a gun-carriage as to prevent the axle striking the stanchions. In cases for smaller galleries also the tenons are sometimes omitted at the bottom of the stanchions, the mortises in the ground-sills cut an inch or two deeper, and the stanchions kept from collapsing by keys driven in the mortises (Pl. XI, Fig. 13). =22. Shaft and Gallery Frames= (Pl. XI, Figs. 14, 15, and 16) are made of scantlings, halved together at the ends, as shown in the figures. _Sheeting_ is made of boards or planks of the necessary thickness, sawn to proper lengths, and bevelled at the ends. When sawn lumber is not available, the frames may be made of saplings, and in some cases poles may be used for sheeting. The middle of each cap and ground sill, both in frames and cases, is distinctly marked by a shallow saw cut or otherwise. =23.= The following table gives the dimensions, in inches, usually adopted for the pieces of cases, frames, and sheeting, for galleries of different sizes, viz.: ----------------+------------------------------------+--------------------------------------------- \| Cases. \| Frames and Sheeting. +------------+-----------+-----------+------------+-----------+---------+---------- \|Ground-sill.\|Stanchions.\| Cap-sill. \|Ground-sill.\|Stanchions.\|Cap-sill.\|Sheeting. ----------------+------------+-----------+-----------+------------+-----------+---------+---------- \| In. \| In. \| In. \| In. \| In. \| In. \| In. Great galleries \| 3 \| 4 \| 5 \| 6 × 4 \| 6 × 6 \| 6 × 9 \| 2 Common galleries\| 2 \| 2 \| 2 \| 6 × 3 \| 6 × 6 \| 6 × 8 \| 1½ Half galleries \| 2 \| 2 \| 2 \| 5 × 3 \| 5 × 5 \| 5 × 7 \| 1½ Branches \| 1½ or 2 \| 1½ or 2 \| 1½ or 2 \| 4 × 3 \| 4 × 4 \| 4 × 5 \| 1 or 1½ Small branches \| 1 to 2 \| 1 to 2 \| 1 to 2 \| 3 × 3 \| 3 × 3 \| 3 × 4 \| 1 ----------------+------------+-----------+-----------+------------+-----------+---------+---------- The cases of branches and small branches are sometimes made very strong, with a view to resist rupture by the explosion of neighboring mines. For this purpose cases made of oak plank 4" thick are used, and the branch near its end is packed full of scantlings provided with rope-handles at their ends for withdrawing them after the mine is fired. This packing is, however, of doubtful utility, since a compression of the case sufficient to call the resistance of the packing into play is very apt to produce a permanent deformation of the cases, which will jam the scantlings and prevent their removal. For convenience in use the pieces of cases should be of uniform width. =24. Relative Advantages of Cases, and Frames and Sheeting.=--In favorable soil, cases, when they can be obtained, allow of more rapid progress and give a lining with a smooth interior. In very bad soil they cannot be used for the larger galleries. Frames and sheeting can be used in all soils which admit of mining operations, and can usually be improvised from materials found in the vicinity. =25. Sinking a Shaft by Frames and Sheeting.=--The size and position of a shaft are usually determined by the character and direction of the gallery which is to start out from it. It is evident (Pl. XI, Fig. 17) that the clear width of the shaft must be enough greater than the outside width of the gallery to allow the side sheeting of the gallery to be freely inserted outside the frames of the gallery and inside those of the shaft; also, that the shaft frames must be so spaced as to leave a clear space at the bottom for the gallery. This space must be equal to the clear height of the gallery, increased by the thickness of the cap-sill, the sheeting, and one or two inches for easy working. This and the thickness of one frame being deducted from the depth of the shaft, the remainder may be divided up into a number of equal or unequal parts called _shaft intervals_. In order that the sheeting may not yield under the pressure of the earth, these intervals seldom exceed 4 feet. The length of the shaft must be great enough to allow the miners to work freely, and to insert the sheeting for the first gallery interval. The sheeting for both shafts and galleries is cut in lengths about 1 foot greater than the interval between frame centres. =26.= The size and position of the shaft having been fixed, the top frame (Pl. XI, Fig. 15) is placed in position and secured by pegs, and the direction of its axis is accurately fixed by the score marks at the middle of the end pieces. The side and end pieces of this frame are respectively about 3 feet longer than those of the other frames, and are so halved together as to make of their ends four projecting _horns_, 1½' long, which keep the frame in place during the excavation of the first interval. This frame is usually placed with its top flush with the surface of the ground. The miner proceeds to excavate the shaft with pick and shovel, making it large enough in plan to admit the sheeting outside the frame. Usually the first interval can be excavated without supporting the earth at the sides, which are vertical or slightly undercut, so that at the bottom of the interval the shaft will be large enough to admit the second frame, the sheeting of the first interval, and a system of wedges which hold this sheeting out from the second frame a distance somewhat greater than the thickness of the sheeting of the second interval. The verticality of the sides is determined by the plumb-line, and the size of the shaft by two gauge-sticks cut respectively to the outside length and width of the excavation, and distinctly marked at their centres. To avoid the inconvenience of working under the top frame, the first interval is frequently marked out and excavated before the frame is fixed in its position. When the shaft is deep enough the second frame is put in place and nailed together; the notches in the ends of the side pieces turned upward and those of the end pieces downward. The top and second frame are connected by nailing to them four battens of proper length (two on each side), which suspend the second frame from the top frame at the established interval. The second frame is placed vertically below the top frame by using the plumb-line and the scores in the frames. The sheeting is inserted outside the top frame, bevelled end first, bevel outside, and pushed down until its top is flush with the top frame. The lower end of the sheeting is held out from the lower frame by suitable wedges, and the excavation of the second interval is commenced. In ordinary soil the sides of the shaft will now require support. Sheeting is therefore introduced and pushed down as the excavation proceeds, and the wedges previously placed are removed to make room for the sheeting. =27.= If the pressure of the earth becomes great enough to spring the sheeting-planks inward, an _auxiliary frame_ is introduced. This is a frame similar to the shaft frames, but from 4 to 6 inches larger in outside dimensions. The sheeting rests directly against the outside of this frame, and is thus held out far enough to allow the third frame to be placed and the wedges to be inserted as before. The auxiliary frame is then removed and used in the next interval. =28.= Successive frames are placed in the same manner until the one directly over the gallery is reached. Great care is taken to place this frame at exactly the right height, and the shaft is then continued to the required depth. A frame is placed at the bottom with its top at the level of the floor of the gallery, and the sheeting is allowed to rest directly against the outside of this frame. When the soil will allow it, the sheeting is omitted wholly or in part over the portion of the shaft which is to form the gallery entrance. =29. Precautions.=--In sinking shafts especial care must be taken to make the excavation no larger than is required for placing the lining, since if a vacant space is left outside the lining the sides of the shaft may give way through its entire height, and fall against the lining with a blow which will crush it in. _This is often the cause of fatal accidents both in shafts and galleries._ =30. Partly-lined Shafts=, i.e., those in which the sheeting-planks are separated from each other by greater or less intervals, should only be used for small depths and when they are expected to stand for a very short time. They are a constant menace to the miners, owing to the danger of their caving in, and in a much greater degree to the probability of stones, etc., falling from the unprotected parts and seriously injuring or killing the men at the bottom. =31. Driving a Gallery with Frames and Sheeting.=--The direction of the gallery has already been marked by the scores on the shaft frames; but it must be verified by plumb-lines, and two small pickets be driven on the line of its axis, which is located exactly by small nails, one driven in the head of each picket. Two gauge-rods are prepared, giving the extreme height and breadth of the excavation, i.e., the height of the frame plus two thicknesses of top sheeting, and the breadth of the frame plus four thicknesses of side sheeting. The middle of each gauge-rod is also plainly marked. A gallery frame is set up against the side of the shaft (Pl. XI, Fig. 17), its ground-sill flush with the bottom frame of the shaft; or its stanchions may rest upon the shaft frame as a ground-sill. The gallery frame is carefully located and fastened in position with battens and braces. The shaft sheeting is then forced down two or three inches with a bar, and the top sheeting of the gallery inserted and driven in until its end is supported by the earth. It is given the proper upward pitch by a scantling laid across it and secured to the shaft frames. The shaft sheeting is forced further down, the earth at the top excavated, and the top gallery sheeting advanced. As this work proceeds the side sheeting-planks are successively inserted and driven forward. In this way the gallery is advanced one gallery interval, usually about 4 feet, when a second frame is placed. Its position is verified by the score marks; for direction, by a line; for grade, by a spirit, mason’s, or field level; and for verticality, by a plumb-line. It is then secured in place by nailing battens to it and the preceding frame. Wedges are inserted between the frame and the sheeting, and the gallery is continued by the same methods (Pl. XII, Fig. 19). When the sheeting is advanced only by hard driving the frames are slightly inclined to the rear at first, and are afterwards driven forward until vertical. =32.= If, while advancing the sheeting, the pressure upon it becomes so great as to spring it, a _false frame_ (Pl. XII, Fig. 18) must be used. This consists of a cap-sill, ground-sill, and two stanchions, connected by mortises and tenons. The stanchions have tenons and the sills mortises at each end. The cap-sill is usually rounded on top and, for facility in setting up and removing, its mortises are longer than the width of the tenons. The latter are held in place by wedges when the frame is in position. The false frame is usually made of the same height as the common frames and, when side sheeting is used, wider by twice the thickness of this sheeting. When side sheeting is not used, its outside width may be equal to the clear width of the gallery. In using the frame (Pl. XII, Fig. 19) the ground-sill is first placed accurately in position at a half interval in advance, the stanchions are set up, and the cap-sill placed upon them and wedged. The whole frame is then raised about 2 inches by folding wedges placed under each end of the ground-sill, and is secured by battens. The sheeting will now rest directly upon the cap-sill and stanchions, and have the proper inclination to clear the next frame by its own thickness, as is required. The next frame is then set up, the wedges driven under the sheeting, and the false frame removed; which is easily done, owing to its construction. =33.= When the soil is very bad a _shield_ (Pl. XII, Fig. 20) is used to prevent the earth in front and above from caving into the gallery. In starting out from the shaft the following method is adopted: As soon as the top sheeting is sufficiently advanced and the shaft sheeting is forced down about 1 foot, the top plank of the side sheeting is inserted and driven forward about 2 feet, and the earth at the top of the gallery is excavated for from 6 inches to 1 foot in advance. A piece of plank a foot wide and in length equal to the width of the gallery is then placed directly under the top sheeting and against the face of the excavation, and is held in place by braces at its ends secured to the shaft lining. The shaft sheeting is then lowered another foot, the next plank of the side sheeting inserted, the earth excavated, and a second plank of the shield placed in the same way as before. This is continued until the entire face is covered. The top and side sheeting are then driven forward, and the top plank of the shield is removed and replaced in advance; after which each plank is removed and replaced in succession, as above described. =34. Inclined Galleries.=--_Method of fixing the slope._--If the gallery instead of being horizontal is _ascending_ (Pl. XII, Fig. 21) or _descending_ (Fig. 22), the proper slope is obtained by using a _slope-block_ whose edge is equal to the rise or fall of the gallery in one interval. This is placed upon the lower of two consecutive ground-sills, and the proper height of the other is determined by a mason’s or spirit level (Fig. 21). If a field-level or a mason’s level properly marked for the slope is used, the slope-block may be dispensed with (Fig. 22). =35. Position of Frames.=--In driving _descending galleries_ better progress will be made and less material used if the frames are set at right angles to the axis of the gallery (Pl. XII, Fig. 22); and this is the usual custom. In driving _ascending galleries_ this is impracticable, and the frames are set vertically (Fig. 21). In all other respects inclined galleries are driven in the same manner as horizontal ones. =36. Partly-lined Galleries.=--In very firm soil side sheeting may be omitted entirely, and in that less firm the side planks need not be in contact. When the side sheeting is omitted the width of excavation may be reduced to the clear width of the gallery, and the stanchions be let into the side wall flush with its surface. In this case the ground-sills are frequently omitted, the stanchions resting upon wooden blocks, stones,or directly upon the earth. To save material, the planks of the top sheeting are sometimes more or less separated also. This can only be recommended when rapid and temporary work is required with limited materials; and in these cases the earth between the planks should be supported by a packing of sticks, brush, etc., etc. =37. Change of Direction in Galleries.=--In changing the direction of a gallery, the new direction is laid off by using a carefully made angle-templet (Pl. XI, Fig. 7) or slope-block, field-level, etc., and it is prolonged in the new direction by the methods already described. When the soil is firm enough to stand safely while excavating and lining one gallery interval, even if somewhat short, no difficulty exists in changing the direction of a gallery in either a vertical or horizontal plane, since the excavation in the new direction may be made so large that the miner working in it can place the new frames and introduce the sheeting and wedges. The gallery can then be carried on without diminution in size. When the soil is bad, however, special arrangements must be made for introducing the sheeting. =38. Change of Slope.=--To pass from a horizontal to an _ascending_ gallery (Pl. XII, Fig. 21) it is only necessary to give the top sheeting the proper angle by holding down its back end with a piece of scantling placed across the gallery for that purpose; and, to give the side sheeting the proper inclination, cutting trenches in the bottom of the gallery for the lower pieces, if necessary. In passing from a horizontal to a _descending_ gallery (Pl. XII, Fig. 22) the roof may be carried forward horizontally, and the floor given the desired pitch by increasing the height of the consecutive frames, until enough head-room is obtained to allow the top sheeting for the descending gallery to be inserted at the proper height and angle. The frame at this point is made with a cap-sill (upon which the sheeting rests directly), and a second cross-piece below it, serving as a cap-sill for the descending gallery. From this point forward the frames may be set perpendicular to the axis of the gallery, as previously stated. If the descending gallery is very steep and the horizontal pressure of the soil great, it may be necessary to strengthen the stanchions of the last two or three vertical frames by cross-pieces near their upper ends. =39. Change of Direction Horizontally.=--Slight changes of direction of narrow galleries, either to right or left, may be made in a manner entirely similar to that above described for descending galleries, by widening the frames until the side sheeting can be inserted at the required angle, and strengthening the cap-sills, when necessary, with additional stanchions. When the gallery is wide or the changes of direction abrupt, however, it is customary to drive the gallery entirely beyond the turning-point, and then break out a gallery in the new direction from the side of the original gallery. =40. Returns.=--A gallery starting out from the side of another is called a _return_, and is _rectangular_ or _oblique_ according to the angle made by its axis with that of the original gallery, which is called the _gallery of departure_. That the return may be broken out, the interval between the frames of the gallery of departure at this point must be such as to admit between the stanchions a frame and the side sheeting of the return (Pl. XII, Fig. 23). This part of the gallery of departure is called a _landing_, and its floor is made horizontal. If the return is oblique (Fig. 24), its width measured along the gallery of departure will be determined by an oblique section, and may be so great that the strength of the lining of the gallery of departure will not allow the necessary length of landing. In this case a short rectangular return is first broken out from the side of the gallery of departure, and the new gallery is broken out from the side of this return (Fig. 25). The latter method diminishes the length of the landing when the change of direction is less than 45°. =41.= The floor of a return is started at the level of the floor of its landing. In firm soils which will stand for a short time without support the first frame may be set up entirely outside the gallery of departure (Pl. XII, Figs. 24 and 25) and may be of the same height in clear as this gallery. When the soil is bad, however, and side sheeting is required in the gallery of departure, the first frame of the return must be set up against this sheeting in the interval between the stanchions of the landing (Fig. 23). This makes the clear height of the return at this frame less than that of the gallery of departure by a little more than the thickness of the sheeting. The first frame of an oblique return should be so made that the sides of the stanchions will be parallel to the side walls of the return, thus giving a good bearing to the side sheeting. In very bad soil, the first few frames of a return must be firmly braced to resist the backward thrust of the earth, by battens connecting them together and by struts across the gallery of departure. The latter are removed when the return is sufficiently advanced. =42. A Complete Map= must be made of every system of mines, showing the centres of shafts, and the axes and slopes of all galleries; giving also the references and lengths of all landings, and the locations, references, and dimensions of all mine chambers. =43. Working Drawings= must also be made from which sheeting can be cut to proper lengths and angle-templets, etc., cut and framed. These can be easily and accurately drawn by remembering that, to allow the miners to insert the sheeting, every return must have such dimensions outside its sheeting that, if it were free to move, its lining could be slid back across its landing as a drawer slides in a table. The size of the landings and dimensions of frames having thus been determined, the parts of the galleries between them may be divided into intervals, which, for convenience, should be equal, since this will allow the sheeting to be cut to a uniform length. =44. Sinking a Shaft with Cases.=--(Pl. XII, Figs. 26 and 27.)--A case of the required size is put together and accurately placed upon the site of the shaft, whose dimensions are marked upon the ground outside it. The case is then removed and the earth excavated to the depth of the case, which is placed in the excavation with its top flush with the surface of the ground. Its position is carefully verified, and it is secured in position by packing earth around it. The excavation is then continued for the depth of another case, which is put in place as follows, viz.: One end piece is placed in position, the tenons of the two side pieces are inserted in the mortises at its ends, and the side pieces are pushed back into position; a pocket-shaped excavation is made with a push-pick beyond the end of one of the side pieces and running back three or four inches into the side wall; the remaining end piece is inserted in this far enough to allow the mortise at its other end to slip over its corresponding tenon; it is then drawn back, and the tenons at both ends fitted into their mortises. The notches cut in the sides of the pieces allow them to be easily handled. The next case is placed in the same way, care being taken not to excavate two consecutive pockets at the same angle. When practicable, it is well to fill up these pockets by stuffing in sods from below before placing the next case. Some miners prefer to place one tenoned piece first, then the two mortised pieces, leaving a wedge-shaped opening behind one of them, and insert the other tenoned piece last, drawing the mortised piece forward upon its tenon. When the sides of the cases are tenoned at one end only and secured by wedges at the other, they are easily placed in position without cutting out behind them. =45.= Upon reaching the level of the top of the gallery, the pieces on the gallery side of the shaft are omitted if the ground is firm, but if it needs support these pieces are put in place and secured by cleats or braces, but the tenons are not inserted in the mortises. =46. Driving a Gallery with Cases= (Pl. XII, Fig. 27).--This is practicable only when the soil is somewhat firm. In breaking out from the side of the shaft, a frame is first placed inside the shaft to support the ends of the shaft cases resting against the pieces which are to be removed. The latter pieces are then taken out and grooves are cut in the earth for the ground-sill, stanchions, and cap-sill of the gallery, and these are put in place in a manner entirely analogous to that described for sinking a shaft. This case is set flush with the inside of the shaft and supports the side pieces, whose tenons rest upon its stanchions. The projecting earth is then cut away and grooves are cut for the next case, which is placed in position and the excavation continued as before. =47.= When the earth shows a tendency to cave, which it frequently will in great galleries, the cap-sill must be put in position and supported while the miner excavates the grooves for the ground-sill and stanchions. To support the cap-sill, two crutches are used. A _crutch_ (Pl. XII, Fig. 28) consists of an upright piece of timber carrying a cross-piece whose length is equal to the width of two cases. The upright piece rests upon the ground-sill of the case already placed, and is raised to the proper height by wedges. The part of the cross-piece which projects in advance is made 2 inches higher than the rear part, to support the cap-sill somewhat above its final level, so as to allow the tenons of the stanchions to be easily inserted. The rear part of the cross-piece is attached to the upright by an iron rod or short chain. So soon as the case is set and adjusted to position the crutches are taken down by removing the wedges, and are replaced under the next cap-sill. =48.= In very firm soil shafts and galleries are frequently driven with cases not in juxtaposition, but separated by greater or less intervals. Pieces of planks (which may be parts of cases) placed vertically and resting against the sides and ends of the cases in shafts, or horizontally and resting upon the cap-sills in galleries, and somewhat separated from each other, are used to support the earth between the cases. The same remarks apply to this construction as to the similar one sometimes used when mining with frames and sheeting. =49. Change of Direction in Galleries Lined with Cases.=--Slight changes in direction in a horizontal plane can be easily and gradually made by setting each case a little obliquely to the one preceding it, and separating the stanchions on one side while they touch on the other, supporting the roof in the wedge-shaped openings, if necessary, with pieces of wood, etc. For an abrupt change, it is better to break out a rectangular return from the side of the gallery and pass from this into the required direction by gradual change. If the return is to be of the same height as the gallery of departure, the cap-sills of the latter, for a distance equal to the width of the return, are lifted off the tenons of the stanchions by struts and wedges, and the first case of the return is set as in breaking out from a shaft; the ground-sill is, however, narrowed by the thickness of the stanchions of the gallery of departure so that the face of the case of the return is flush with the inside of the gallery of departure, and the ends of the cap-sills of the latter rest upon the cap-sill of the first case of the return. =50. Change of Slope.=--In passing from a horizontal to a _descending gallery_ the change may be made gradually, in a manner similar to that described for a change in horizontal direction, and the cases remain normal to the axis of the gallery. (Pl. XII, Fig. 31.) To pass to an _ascending gallery_ by the method above described would require the earth at the face of the gallery to be undercut in order to introduce the case, and this undercutting would be continued so long as the cases were normal to the axis of the gallery. This construction is, as a rule, impracticable. In ascending galleries, therefore, the cases are set with their stanchions vertical, while their cap and ground sills lie in the slope of the roof and floor of the gallery. =51.= To conform with this requirement, and for convenience in setting up, the ends of the stanchions receive the proper bevel, while the sides of the tenons and mortises are made parallel to the sides of the stanchions. (Pl. XII, Fig. 12.) =52. Shafts à la Boule.=--In order to place a charge of explosive directly under the ground occupied, or for other reasons, it is frequently necessary to sink a small shaft in the least possible time. For this purpose a modified form of cases is sometimes used, in which the ends are halved together instead of being tenoned and mortised. (Pl. XII, Fig. 29.) They are spaced at greater or less distances apart, according to the nature of the ground, and are connected together by battens. Stones, pieces of wood, etc., etc., are driven between them and the sides of the shaft to support the latter. This construction is called a shaft à la Boule. It is expected to stand for a few days at most. Many other extemporized linings may be used for similar purposes. =53. Blinded Galleries.=--Galleries cannot be successfully driven with less than 3 to 3½ feet of undisturbed earth over their sheeting. In making a descent into a ditch, or in pushing forward an approach in siege operations, it is often impracticable to lower the bottom of the trench of departure sufficiently to give the requisite cover for starting a gallery at once. In these cases _blinded descents_ or _galleries_ may be used, the tops and sides of which are supported by _blindage-frames_, or _blinds_, each of which consists of two side parts of 4" × 6" scantling 9' long, united by two cross-pieces of the same section 3' 8" long, which are mortised or halved into them, leaving horns at each end 1' long. (Pl. XII, Fig. 30.) =54.= The galleries are constructed as follows (Pl. XII, Fig. 31): A double sap with a width of 8' is broken out from the side of the trench in the direction required and is driven forward in the usual manner, but with a continual increase in depth, at a slope not exceeding 1/4. The side slopes are as steep as the earth will allow. Two blindage-frames are set up vertically on the sides of the sap, 7' apart in clear, with their tops at the level of the tops of the trench gabions, their bottom horns resting in holes dug for them. These frames are prevented from falling inward by another frame placed crosswise upon them, with its horns resting on their cross-pieces. The side of this top frame toward the front may be held up by a stake or crutch, and the second pair of frames be placed at such an interval that their horns will interlock with those of the top frame. Successive frames may be placed in the same manner. The covering or “roof” is formed by three or four layers of fascines placed across the trench on top of the frames, and covered with earth thrown back upon them as the work proceeds. The sides of the gallery are held up by fascines, etc., laid along outside the frames. As soon as the bottom of the blinded gallery has reached the proper depth a mine-gallery may be started and carried forward. =55.= The blindage-frames described above give to the gallery a clear width and height of 7'. For smaller galleries the blinds may all be made shorter and of lighter scantling; or, if desired, those for the sides may be of a different length from those for the top. =56. Rate of Advance of Galleries.=--The following table gives an estimate of the men and tools required for shafts and galleries, with the probable rate of advance in good soil: KEY: NC O = N. C. Officer. M = Miners. P = Picks. MP = Miners' Picks. P-p = Push-picks. Sh = Shovels. MS = Miners' Shovels. MT = Miner’s Truck. F-l = Field-levels. M-r = Measuring-rod 6´. T-l = Tracing-line. M S = Mauls or Sledges. CB = Canvas Buckets. R-l = Rope-ladder. W-b = Wheel-barrows. MB = Miners' Bellows. Pr. = Progress, ins. per. hour. -------------------+-----------+---------------------------------------------------------------- \| Men. \| Tools. Kind of Gallery, +----+------+---+---+---+---+---+-----+---+---+---+---+---+---+---+---+------ etc. \|NC O\| M \| P \| MP\|P-p\| Sh\| MS\| MT \|F-l \|M-r\|T-l\|M S\|CB \|R-l\|W-b\|MB \| Pr. -------------------+----+------+---+---+---+---+---+-----+----+---+---+---+---+---+---+---+------ Great gallery or } \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| Blinded gallery } \| 1 \|12[14]\| 4 \| 2 \| 2 \| 8 \| \| \| 1 \| 1 \| 1 \| 1 \| \| \| 4 \| \| 12 Common gallery \| 1 \| 4 \| \| 1 \| 1 \| 2 \| 1 \| 1 \| 1 \| 1 \| 1 \| 1 \| \| \| \| 1 \| 12 Half gallery \| 1 \|4[15] \| \| 1 \| 1 \| 2 \| 1 \| 1 \| 1 \| 1 \| 1 \| 1 \| \| \| \| 1 \| 16 Branch gallery \| 1 \|4[15] \| \| 1 \| 1 \| 2 \| 1 \| 1 \| 1 \| 1 \| 1 \| 1 \| \| \| \| 1 \| 24 \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|{ 30 Small branch \| 1 \| 3 \| \| 1 \| 1 \| \| 2 \|1[16]\|[17]\| 1 \| 1 \| 1 \| \| \| \| 1 \|{ to \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|{ 36 \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| Shaft \| 1 \|4[18] \| \| 1 \| 1 \| 2 \| 1 \| \| 1 \| 1 \| 1 \| 1 \| 1 \| 1 \| \| \|{ 18 \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|{ 24 -------------------+----+------+---+---+---+---+---+-----+----+---+---+---+---+---+---+---+------ VENTILATION OF MINES. =57.= The gases resulting from firing mines and from the lamps, bodies, and candles of the miners so vitiate the air in galleries that, unless means for ventilating them are adopted, the miners must eventually abandon them or become asphyxiated. In ordinary circumstances, when no powder gases are present, a gallery cannot be driven safely more than 60 feet without ventilation. The measures adopted for ventilating galleries consist, 1st, in forcing in fresh air; 2d, in drawing out foul air; and, 3d, in assisting the natural diffusion and circulation of the air through them. =58.= The first is accomplished by forcing air through pipes, which may be of tin, wood, or common hose, leading to the point where ventilation is required. The air is forced in by the use of the miner’s bellows or other apparatus already described. This method is simple in its application and places the fresh air where it is needed, but drives the foul air back into the galleries occupied by other miners. It is the only practicable method of ventilating single, long, narrow galleries and branches. =59.= The second method may be applied to a system consisting of a number of galleries connected by transversals, by so placing an exhausting fan as to draw the air out through one gallery, while by light wooden or canvas doors and screens the other galleries are so arranged that the fresh air, entering from the exterior, sweeps through the galleries occupied by the miners, and escapes through the unoccupied gallery leading to the fan, carrying the gases with it. In this method a single large gallery may be ventilated by using a canvas partition placed near the top or on one side, so that the fresh air will go in on one side around the end of the partition and back by the other side to the fan. This method has the advantage of carrying the gases away from the galleries occupied by the men, and supplying fresh air throughout those which are occupied. The exhaust may be produced by a fire constantly burning at the foot of a shaft instead of by a fan. The method is, however, complicated in its application, and can seldom be used for military mines. =60.= The third method, or assisting natural ventilation, is carried out by cutting numerous cross-galleries connecting those which are near each other, by making air-shafts and bore-holes connecting the galleries with the surface of the ground, and, when practicable, by placing the openings of the shafts and galleries at different levels. This method will serve for a few men working leisurely in preparing countermines before an attack, but is entirely inadequate during active mining operations. =61.= By the use of masks covering the face, and supplied with fresh air either through hose or from a reservoir of compressed air carried with him, a miner may work in galleries in which the air is irrespirable. The advantages which may frequently result from the time thus saved justify providing apparatus of this kind for use in mining operations. MINE-CHAMBERS. =62. Mine-chambers= to contain the charge of explosive are preferably nearly cubical in form, and if not charged at once, or if of large size, must have sufficient lining to support the roof and sides. When they are above the level of the gallery they are arranged to drain into it. They are made large enough to contain the receptacle for the charge and to allow the charge to be placed in it. They are, as a rule, placed in short returns at one side of the branch or gallery, but may be at its end, above or below it. The mine-chamber frequently consists of so much of the end of the gallery as is necessary to contain the charge. LOADING AND FIRING MINES. =63. Preparing the Charge.=--The weight of the charge necessary to produce the desired effect is determined by the rules previously given. Its volume, if of powder or compressed gun-cotton, may be found by allowing 30 cubic inches to the pound; and if of dynamite, about 20 cubic inches. If the mine-chamber is perfectly dry, and the mine is to be fired at once, a layer of straw may be placed upon the floor of the chamber and the charge contained in canvas bags laid upon it. When the ground is more or less wet, or when the mine is not to be fired immediately, the charge should have a water-proof covering, which may be a thoroughly calked and pitched box, an ale-barrel or beer-keg, the metal barrels in which powder is shipped, or India-rubber or pitched-canvas bags,--depending upon the amount of moisture present and the time that the charge is to remain in place. Many of the high explosives are not affected by dampness, and but little if any by water; but to secure the fuse and its connections from injury, and to remove all danger of misfires, the explosive should in all cases be protected from water if practicable. =64. Distribution of Fuses in the Charges.=--Gunpowder will explode with full effect if ignited, but to prevent the explosion of the central part of a large charge scattering the exterior portion before it is ignited a number of fuzes should be used. They may convey fire only, but must all be ignited by the firing apparatus, and simultaneously. One fuze to each 100 lbs. of powder is not too great an allowance; but when lack of time or appliances does not admit of placing a number of fuzes, the desired effect may be obtained by increasing the charge of powder and using one fuze. (See Abbot, Prof. Papers Corps of Engineers, No. 23, 1881, p. 62, for number of fuzes needed; and pp. 244-51 for simultaneous ignitions.) The high explosives detonate with full force only when exploded with a detonating fuze. Under favorable conditions one fuze will detonate a very large charge, but cases arise in which a portion of the charge explodes and the remainder does not. To insure the best results, therefore, it is desirable to distribute fuzes throughout a large charge, at the rate of perhaps one fuze to each 50 lbs. These fuzes should contain from 20 to 30 grains of fulminate of mercury, which is itself very sensitive to shock, and has in a high degree the power of detonating the other explosives. One fuze only (or, for safety against defects, two or three) need be connected with the firing apparatus, the others serving to reinforce and carry on the wave of explosion after it is started--differing in this respect from their use with charges of gunpowder.[19] =65. Character and Construction of Fuzes.=--Formerly, for firing mines, trains of powders put up in linen tubes, quick-match, and other similar devices were used. Electric-blasting apparatus is now in such common use that it will always be available for any extended mining operations. For single mines with small charges it may, however, be necessary sometimes to resort to the older method of firing, the apparatus for which can be readily improvised. But even in these cases “Bickford” or “Safety” fuze will usually be available, and may be used alone for firing gunpowder, or with a common fulminate-of-mercury “blasting-cap” for high explosives. It burns at the rate of about 4 feet per minute. Very quick-burning fuzes are also made which may be used at times (e. g., _Bickford Instantaneous_, which burns at the rate of 120 feet a second; _Gomez Lightning_, which burns so rapidly that it may almost be said to detonate; etc.) Great care must be taken not to mistake them for the common Bickford. =66. Electric Fuzes= are made of three general classes: First, those which are fired by a spark from a high-tension machine; second, those which are ignited by a current from a battery or “dynamo;” third, those which can be fired by either. (Abels, etc.) =67.= Those of the second class are manufactured in large quantities, and, in connection with a portable dynamo or “blasting-battery,” are almost universally used for blasting operations throughout the United States. These fuzes (Pl. XII, Fig. 32) are made up of two insulated copper wires, _A_, _A_, passing through a small cylindrical block of insulating material, _B_, and terminating about 1/16 inch above its end. A very fine platinum wire, _C_, about 1/1000 inch in diameter and 1/8 inch long, connects the ends of the insulated wires. Surrounding the platinum wire is a small quantity of gun-cotton, mealed powder, or fulminate of mercury, _D_. A copper capsule containing 15 to 30 grains of fulminate of mercury, _E_, is pressed down over the cylindrical block far enough to bring the fulminate in contact with the material surrounding the platinum wire, and the whole fuze is then coated with a water-proof composition. The insulated copper wires are cut to various lengths for convenience in connecting with the conductors or lead wires from the battery. =68.= Fuzes of the first and third classes are now but little used. Many of them are unsatisfactory and dangerous. They differ in construction from those of the second class principally in that the platinum-wire bridge is omitted, and the exploding spark or current passes from one insulated copper wire to the other through a material which is ignited by it. =69. Placing the Fuses in the Charges.=--A certain number of cartridges or packages should be selected, each fuse inserted and well packed in the explosive, and the wires or free end of the safety fuse brought out through the opening, which should be made water-proof, if necessary, by securely closing and thoroughly pitching it. The wires or exterior part of the fuse should then be securely fastened to the outside of the cartridge, so that an accidental strain upon them will not break the waterproofing or move the fuse from its place. They are then coiled up and remain so until the cartridge is placed in the general charge of the mine. =70.= Several of the high explosives congeal at a temperature above the freezing-point of water, and in this state are less sensitive to shock, and explode with difficulty if closely packed in cartridges as usually delivered from the factories. They explode more readily when in the form of a powder. When using them in cold weather, therefore, each fuse should be put in a cartridge loosely filled with the powdered explosive, or with some high explosive not affected by cold. Others need special primers to cause detonation. The fuses should, of course, be placed in these primers. =71. Placing the Charges.=--The charge is placed in the mine-chambers, either in the dark, by light reflected through the galleries, by closed lanterns carefully placed and guarded, or, when practicable, by incandescent electric lights. It is carried through low and narrow galleries on men’s backs or in miner’s cars, and should for this reason be put up in packages not exceeding 50 lbs. in weight. It is packed in the chamber with great care, and under the immediate supervision of the responsible officer. The packages containing the fuses are distributed uniformly throughout the mass, and the wires uncoiled and led back into the gallery, the free ends of the two wires of each fuse having been previously twisted together for safety against electric currents and for identification. These wires, which must be long enough to reach through the tamping, are all collected together and led back through it in a wooden or other conduit, which protects them from injury while tamping the mine. When electric lights are used, great care must be taken to remove the light and all its conducting wires before the wires of the fuses are uncoiled and laid along the gallery. =72. Tamping.=--Mines are tamped with sods and earth, wood and earth, sand-bags, etc., etc. When sods are used the branch is filled for about 3 feet with sods carefully laid and packed with the joints filled with earth. About 3 feet of earth is solidly packed against this, then alternate layers of sods and earth until the desired length of tamping is obtained. To tamp with wood and earth or sand-bags, a wooden shield is first placed across the branch and firmly braced; behind this, earth is solidly packed or sand-bags carefully laid until the required length of tamping is obtained. Sometimes a second shield is put up behind the earth tamping, and firmly braced in position. The strength of the tamping is also increased by pieces of timber crossing each other diagonally, with their ends resting against the sides of the branch. Sand-bags make the best tamping, as they offer high resistance and are easily placed and removed. The tamping should have a length equal to at least 1½ times the line of least resistance of a common mine corresponding to the charge, and if not of the best quality, to twice this line. =73. Firing Mines.=--If electric fuses are used the main conductors or lead wires coiled upon a reel are taken in and the ends properly joined to the fuse wires; they are then led through the galleries, attached to the battery, and fired at the designated instant. Under no circumstances should the main lead wires be connected to the battery or dynamo until everything is ready for firing. If a Bickford fuse is used its length is regulated to the desired time of firing from its known rate of burning. The miner lights the end and retires; the explosion takes place approximately at the calculated time. With the “Lightning Gomez” or similar fuses a length reaching to the firing-point may be used. It is lighted at the desired time, and burns with such rapidity that for lengths not exceeding 300 or 400 feet the time of burning is inappreciable. Instead of using great lengths of these fuses, they may be cut shorter and their ends be brought together and inserted in a little mealed powder which is fired by a piece of safety-fuse, slow match or port-fire, etc., long enough to give the miner time to retire to a safe distance after igniting it. Bickford fuse is best ignited by a piece of cotton wicking soaked in oil and loosely tied around it. This, when lighted, will burn through the covering and set fire to the composition. By this device many fuses may be ignited in a short time. A slow match or “touch-paper” for igniting quick-burning fuses or powder-trains may be made by soaking common paper in a strong solution of nitre and drying it. CAMOUFLETS BY BORING. =74.= In favorable soil a camouflet or small mine may sometimes be placed and fired very quickly by the following process: A hole 2" to 3" in diameter and of the desired depth is bored in the proper direction with an auger or boring-bar. A cartridge containing from ½ lb. to 2 lbs. of dynamite is pushed down to the bottom and fired. The explosion increases the diameter of the hole somewhat throughout, and obstructs it more or less with loose earth. At the same time it enlarges the part near the seat of the charge into a bottle-shaped cavity, whose size varies with the charge used and the nature of the soil. The hole is rapidly cleared out with a long-handled scoop, the cavity filled with powder, primed, and fired. The enlargement made by the charges of dynamite above given may contain from 50 to 100 lbs. of gunpowder under favorable circumstances. =75.= In stony soil this method becomes very difficult if not impracticable; and when it can be used the preliminary explosion of dynamite vitiates to a greater or less degree the air of the shaft or gallery from which the boring is made, and also informs the enemy of the progress and intention of the miner. To remove the latter objections, the English authorities recommend the use of holes 6" or 8" in diameter, bored with earth-augers, charged to a length of 2 or 3 calibres, and well tamped. When applicable, this method is manifestly a great improvement upon the other; but the auger is so liable to be stopped by stones which a boring-bar might break or push to one side, that it can only be applied in very favorable soil. CHAPTER III. ORGANIZATION AND TACTICS OF MINES. =76. Organization of Mines.=--Underground warfare is conducted in the dark, in bad air, with constant danger of caving earth, suffocation by noxious gases, destruction of men and galleries by intentional explosions of hostile mines or accidental ones of our own, in addition to the usual dangers and difficulties of opening and supplying the mines under the close fire of the enemy. These considerations necessitate the rejection of all complicated systems in the attack, and in the work carried on by the defence during the siege. Ignorance of the point to be selected for attack, and the great expense of permanent countermines, also require those prepared beforehand by the defence to conform to simple and economical systems. For this reason it is not necessary to give in detail the systems proposed by the older writers. They are described in most of the extended treatises on military engineering. =77. The Attack.=--The object of the attack is to advance his galleries in the most rapid manner possible, with the best available system of ventilation, and to place his mines in such position as to break up the galleries and destroy the men, materiel, and works of the defence, both above and below ground; or to form connecting craters which may be occupied and converted into parallels, trenches, etc. =78.= To accomplish this, when no natural ravine exists, a deep trench or “_lodgment_” is made, usually connecting the entrances of all the galleries and serving as a communication between them, and as a depot for such supplies as must always be at hand. From this lodgment the galleries are started by a shaft, blinded descent, or mining-gallery; the method depending upon the depth to be reached and the thickness of cover required. The entrance of each gallery is protected from horizontal and vertical fire, and from splinters, by a bomb-proof cover and traverses of sufficient thickness and strength. The galleries are generally driven in lines nearly parallel, and at such distance apart that the hostile miners working at any point between them will be heard, either from the main galleries or from returns called “_listening-galleries_” or “_listeners_.”[20] Depending upon the depth at which they are placed and other circumstances arising in different cases, the main galleries in various sieges have been placed at distances apart varying from about 8 to 30 yards. These galleries are connected at intervals by “_transverse galleries_” or “_transversals_,” which assist the ventilation very much and give additional communication between them. Branches for placing mines are driven in prolongation of the gallery or obliquely to the right or left, and, when the gallery is at a low level, inclining upward so as to shorten the line of least resistance, economize powder, and diminish the injury to the gallery and branches, resulting from the explosion of the mine. =79.= When the hostile miners come within striking distance of each other, each strives to run his galleries directly toward the other in order to avoid exposing its flank to the hostile mine; thus diminishing as much as possible the injury resulting from its explosion. =80.= The mines of the attack are generally overcharged in order to do the greatest possible injury to the mines of the defence, and to open large craters, but undercharged mines and camouflets are also used at times. =81. The Defence.=--The object of the defence is to retard or stop the advance of the attack, by the destruction of his mines and miners, without forming craters which will assist him in making his parallels and approaches. =82.= For this purpose his galleries must satisfy nearly the same conditions as those of the attack. They usually start out from the counter-scarp gallery or from a parallel gallery a little in advance of it, and extend to a greater or less distance from the work, according to the time and expense allowable for their construction. For permanent works they are frequently prepared in time of peace, and lined with masonry. It is particularly for this class of countermines that many elaborate systems have been designed for completely covering the ground, and for throwing up the same earth several times by mines placed at different depths and exploded in succession. For reasons previously given, these cannot be recommended. =83.= A simple system of galleries placed as far below the surface as practicable, parallel or slightly diverging, connected when necessary by transversals whose lines prolonged pass inside the enceintes, and with branches fulfilling the same conditions driven out for listening-galleries, will, under the direction of an energetic officer, fulfil the conditions of defence as well, probably, as any that can be devised. The branches leading to mine-chambers can be driven out from the main galleries, transversals, or listeners, as may be desired; and if the hostile miners obtain possession of any part of the system and blow it up, the lines of craters formed will be so swept by the fire of the work that they can hardly be occupied by the enemy. =84.= As a rule, the mines of the defence will be undercharged or camouflets, to avoid the formation of exterior craters, but the rule is not without exceptions. =85. Shaft Mines=, mines placed in vertical shafts, are used by both attack and defence for destroying galleries, etc., in their vicinity. By the attack they are usually placed in craters already formed, or in other places protected from hostile fire. A shaft is sunk rapidly, generally “à la Boule,” heavily “overcharged,” filled up with earth, and fired. The defence may use the same method or may sometimes prepare them beforehand, tamping them and leaving a tubular opening through the tamping for loading and firing them. MINE TACTICS. =86.= The tactics of mine warfare result directly from the consideration above given. The special details of attack and defence vary in each particular case. The reports of mining operations in different sieges[21] supply precedents and give suggestions for future operations of a like character. =87. Todleben’s Rules.=--The general principles of mine tactics have been laid down by General Todleben from his experiences at Sebastopol (in Royal Engineers Occasional Papers, vol. i., 1877). They may be summarized as follows: =88. The Attack.=--The besieger should advance by several galleries, securing those on the flank by listeners. He must be active and persistent, as the enemy will use every available moment to develop his countermines. When he receives the first camouflet of the defence he must hasten to fire his overcharged mines in the uninjured branches, in order to destroy the hostile countermines. He will generally suffer losses more or less heavy from this epoch forward, but must submit to them; since too much circumspection and delay will almost always result in complete failure. Before firing the overcharged mines he must have everything in readiness to occupy and intrench himself in the craters formed; to open communication from the trenches to the craters either by sap or by forming a line of connecting craters; and for constructing shelters for the party occupying the craters and holding them against the sorties of the defence. After occupying the craters, he should drive forward his galleries from them at once, unless the besieged has anticipated him and surrounded the craters with branches--which may be assumed to be the case if any delay has occurred in occupying it. In this case he should sink shafts à la Boule, heavily overcharged, and fire them, and immediately occupy the new crater and push out from it; and thus progress as rapidly as possible, by constantly placing and firing overcharged mines, whose craters will, with little alteration, form both communications and parallels. When the fire of the defence upon the crater is so severe that a deep shaft cannot well be sunk, a shallower one with correspondingly small charge is first sunk and fired, and a deeper one is sunk from the crater thus formed. The overcharged mines should be well tamped when time permits. If not well tamped the charge should be increased (_or high explosives used._--J. M.). =89. The Defence.=--The defence should push out his galleries as far as possible and at the earliest practicable date, connecting them by transversals for ventilation, and holding them at a level below any likely to be reached by the attack. When near the enemy, he should stop work several times a day and listen for sounds from the hostile miners which will locate their position. Hearing the sound of the enemy’s miner, he may work toward him noiselessly, or prepare and charge a chamber and await the approach of the miner toward it, listening at the point where the hose trough (_tube for fuse wires._--J. M.) comes through the tamping until the enemy is near enough to justify firing. Judgment as to distances must be formed from practice obtained while driving the countermines. To avoid forming craters on the surface, and to do the greatest possible damage to the besieger’s works, the besieged should not fire his mine until the enemy’s distance from it is less than the line of least resistance reckoned toward the surface. When this condition is fulfilled, he may give to his camouflet a charge of from 3/10 to 4/10 the charge for a common mine placed at the same depth, since the charge will produce its principal effect upon the enemy’s gallery, and but little upon the surface. Special care must be exercised by the defence to avoid premature explosions, since a mine fired at too great range damages only his own branch, and may make a crater; thus working directly to the advantage of the attack, who may prepare an overcharged mine or sink a shaft à la Boule in the crater thus made. As successive explosions of necessity damage the branch in use, to avoid falling back, another one should be prepared as a reserve before the first is disabled, and at a little distance from it. After the attack has fired his overcharged mine, the defence, by a strong fire of canister, musketry, etc., should prevent him from occupying the craters, and if he takes possession, should drive him out by a continuous mortar fire, keeping him from completing his communications by fire from guns. The defence should push forward branches and establish himself under the slope of the craters, in front and on both flanks, and by exploding camouflets prevent the attack from driving galleries or sinking shafts à la Boule. When the nature of the soil admits, many of the camouflets will be placed by boring. Should the defensive measures above and below ground not debar the enemy from establishing himself in the crater, the defence may establish overcharged mines immediately in its front, with a view to destroying the advancing galleries of the attack, blowing up the men and their lodgment in the crater, and opening up the latter to the fire of the work. Shafts à la Boule being very dangerous for the countermines, the defence should do his best to prevent their use, by artillery and musketry fire above ground, and by camouflets placed by boring under ground. In addition, he must take advantage of every favorable opportunity to delay the progress of the attack by sorties from the works. =90. Remark.=--In underground warfare the besieger has a decided advantage, but the besieged, by a cool consideration in handling his mines, and by persistently holding back the attack, foot by foot, may very greatly retard it, or even cause such losses and delays as to lead to its being abandoned. BREACHING BY MINES. =91.= The attack having reached the scarp of the work, mines are prepared for breaching the counter-scarp and scarp. Experience shows that the charges are best located in rear of the counterforts when they exist, or at equal intervals along plain walls. The charge should not be placed immediately in contact with the masonry, but in the earth behind it, and at a depth below the top of the wall equal at least to 1½ the L. L. R., measured to the face of the wall. The charge should be estimated by the rules already given, and increased by 20 to 30 per cent, so as not only to throw down the walls, but also to break up the earth and form a practicable breach. =92.= The galleries for placing the chambers behind the counterscarp are branches from the gallery of descent into the ditch; those behind the scarp may branch out from a gallery driven under the ditch, when water or rock do not forbid, or from a gallery driven through the scarp wall after crossing the ditch by sap or by a bridge. =93.= To start the gallery through the scarp wall, a miner is “_attached_” to the wall by protecting him from fire along the ditch, from sorties, and from loaded shells, etc., rolling down upon him from the parapet by suitable traverses and splinter-proof. This operation is of course very dangerous, and is generally impossible unless the fire of the defence along the ditch is previously silenced. To expedite the work of the miner a gun is sometimes brought down through the gallery, and the face of the wall is shattered by its fire before the miner is “=attached=.” CHAPTER IV. BLASTING AND DEMOLITIONS. BLASTING. =94. Blasts= are small mines used generally for breaking up rocks, or masonry in demolitions. =95.= Holes for placing the charges are drilled usually with _drill-bars_ or _churn-drills_, known also as _jumpers_. These are steel bars sharpened to a chisel edge. The _drill-bar_ is usually held by one man and struck with a hammer by another; it is turned slightly after each blow in order to make a round hole. For small holes the driller holds the drill in one hand and strikes with the other. The _churn-drill_ is a longer bar, generally sharpened at both ends and enlarged in the middle. It is used for drilling vertical holes by raising and dropping it in the holes, turning it slightly after each blow. =96.= The _charge_ may be gunpowder or high explosive. If the former, it must be thoroughly tamped. If the latter, tamping will greatly increase its effect; but it is in some cases preferable to obtain the desired effect by increasing the charge and saving the time taken in tamping. =97.= Blasts are fired by electric fuses, Bickford fuse, firing-tubes, needles, etc. The fuses have been already described. The _firing-tube_ is a very small iron pipe, which is inserted in the powder charge and the tamping rammed around it. After the tamping is finished the tube may be filled with fine powder poured in it if the hole is vertical or inclined downward, or straws filled with powder may be inserted if it inclines upward or is horizontal. A “squib” of wet powder is also sometimes placed in the tube and ignited, when it passes down the tube like a rocket and fires the charge. The _needle_ is a smooth copper wire, longer than the depth of the hole. It has a ring handle, by which it may be turned around and withdrawn. It is inserted in the charge, the tamping is well rammed around it, and it is withdrawn, leaving a pipe in the tamping, through which fire may be communicated, as described for the firing-tube. =98. Tamping.=--The best and safest tamping is perfectly dry silicious sand, poured in the hole so as to fill it completely, but not rammed. It cannot be used in holes which incline upward nor when the needle is used. In such cases moist clay, brick-dust, etc., are used. The first layers are pressed in upon the charge, and the subsequent ones thoroughly rammed down with a copper tamping-bar. A hammer is used with the bar, when necessary, in deep holes and hard rock. _With high explosives no tamping should be used except dry sand or water. Holes which incline upwards should receive an extra charge and be untamped._ =99. Determining the Charge.=--The charge of gunpowder or high explosive required for any particular hole in ordinary blasting can be best estimated by an experienced blaster. If one is not to be obtained, an approximate estimate for the first experiment may be made from the formulas (counting the high explosives about four or five times as strong as gunpowder for ordinary use), and the charges for subsequent blasts may be estimated from the effects of those first fired. =100. Precautions.=--If a _tamped_ hole misses fire _it should never be cleared out for recharging_. A new hole should be drilled near, but not breaking into it. Electric fuses or Bickford fuses (with blasting-caps for high explosives) should always be used when they can be obtained. DEMOLITIONS. =101. Deliberate Demolitions=, such as the destruction of walls, casemates, etc., in time of peace, or at a distance from the enemy in time of war, should be so made as to economize powder and work. To accomplish this, the mines and blasts should be located where they will produce the best effects attainable, and the charges should be proportioned to the work required from them. The table previously given (p. 124) will serve as a guide for computing the first charges used, and from the results of these the charges of subsequent ones may be determined. Judgment must be used in placing the charges, so that, when possible, they will destroy the supports and allow the superstructure to break up by falling. The charges will usually be placed in chambers under or hollowed out in the masonry. Sometimes they are more advantageously placed in a trench outside and close to the foot of the walls. They should always be well tamped: when in mine-chambers, by methods previously described; when in trenches, or laid along the exterior of walls, by loading them with earth, etc., until the line of least resistance passes through the wall to be destroyed. =102. Hasty Demolitions= are made when the time available for the work is limited. The structures usually destroyed are houses, walls, stockades, bridges, tunnels, canal-locks, railroads, rolling-stock, etc., etc. The time does not usually allow the charge to be placed in the most advantageous position or to be properly tamped. For this reason the high explosives are best suited for this kind of work, and large charges are a necessity. =103. Houses and Magazines= are best destroyed by placing several charges with connecting trains inside and along the walls, laying strong timbers upon them, with struts from the timbers to the floors and roof above; barricading the doors and windows from within, and firing the powder from a safe distance without. =104. Walls.=--A wall not exceeding 3 or 4 feet in thickness may be breached by charges of gunpowder placed at intervals along it. Calling the thickness of the wall in feet _t_, the charge in pounds may be 3_t_^3, placed at intervals of 2_t_. For gun-cotton the Woolwich rule calls for charges in pounds of from ⅓_t_^2 to ½_t_^2 per running foot. Experiments made in New York with dynamite indicate that the charges should be at least ½_t_^2 per running foot, and for very good masonry should exceed this. A charge of dynamite of ½_t_^2 per running foot will be given by a cylindrical cartridge whose diameter in inches equals the thickness of the wall in feet.[22] The effect of the charge will be very much increased by throwing over it even a very light tamping of earth or sand. =105. Stockades.=--A strong stockade or palisade may be broken down by charges of from 40 to 60 lbs. of gunpowder placed in contact with it, and preferably covered with sand-bags. 10 or 15 lbs. of high explosive should produce about the same effect. =106. Bridges.=--Arched bridges are best attacked in the piers if high and thin, or at the haunches and crown of the arch. Two or more charges in the length of the pier, or width of the roadway, will be more effective than the same amount in a single charge at the middle. The charges should be placed in chambers cut in the piers or down through the roadway to the back of the arch. The abutments of single-span arches are generally very strong, and the haunches well covered with earth and masonry. In hurried work, therefore, the crown will generally be selected, a trench dug down to it across the roadway, the charge placed in the trench, tamped if possible, and fired.[23] High explosives, from their shattering effect, are perhaps most advantageously used by suspending them beneath and in contact with the arch at the crown and haunches. The plank or timber upon which they are placed should be as heavy as possible, in order to act as a partial tamping, and should be drawn up so that the explosive will be in actual contact with the soffit of the arch. Under these circumstances they should produce as great an effect as four or five times their weight of gunpowder. Iron and wooden truss-bridges should be thrown down by breaking the main braces near the piers, or the chords near the centre, by charges placed in a joint if possible. High explosives are particularly valuable for this purpose. In wooden bridges they may be placed in auger-holes bored for them, and in iron bridges inside the hollow members, between eye-bars, or in other similar places. =107. Tunnels, Canal-locks=, and similar constructions must be attacked with large charges, so placed as to temporarily or permanently disable the work, as may be considered necessary. The location of each charge should be determined and its amount computed from these considerations before the destruction is attempted. A temporary obstruction is frequently all that is necessary or desirable for these works, and the damage done to them should be carefully regulated with a view to their subsequent repair and use. =108. Railroads.=--Railroads are temporarily disabled by tearing up the track, making hot fires of piles of ties, placing the rails upon them so that they will heat and bend by their own weight; or, better still, twisting the rails while hot by suitably-shaped steel hooks and wooden levers of the kind devised by General Haupt (Pl. XII, Fig. 33). Rails so twisted cannot be again used until re-rolled. =109. Rolling-stock.=--Railroad cars may be disabled by breaking one or more wheels with sledges, or may be destroyed by burning. Locomotives may be disabled temporarily by carrying away the smaller parts of the mechanism, or permanently by breaking the engine-cylinders with sledges; bursting the boilers or burning out their fire-boxes by drawing out nearly all their water, fastening down the safety-valves, and building a hot fire in the furnaces; or by making a hot fire under them so as to heat and thus bend or warp the reciprocating parts of the machinery. =110.= In all hasty demolitions with explosives the charges should be well in excess of those computed by the ordinary rules: first, because the explosives will not be so placed as to act to the greatest advantage; and, second, because the demolition should be _immediate_ and _complete_. INDEX. A PAGE Additional operations--intrenched camps, 91 Advance from first parallel, 84 Advanced positions, 104 Advantage lies with attack, 176 Ammunition, 44, 57, 101 Angle template, 137, 148 Approaches, 16 Approaches, execution of, 20-3 Approaches, tracing, 18 Approaches, over-ground, 31 Ascending galleries, 148 Armament, 100 Army of observation, 69 Artillery, first position, 75, 104 Artillery, first position opening fire, 67 Artillery, second position, 81 Artillery, second position opening fire, 83 Artillery-fire, opening, by defence, 104 Assault, 4 Assault, defence against, 7 Assault, dispositions for, 5 Assault of breach, 89 Attaching a miner, 177 Attack by mines, 169-171 Attack by sap, 91 Attack, close, 107 Attack, journal of, 97 Attack, plan of, 78 Attack, point of, 73 Attack, successive steps of, 64 Auger, earth, 138 Auxiliary frame, 144 B Battery, alternative construction, 50 Battery behind crest of hill, 53 Battery, breaching, 83 Battery, construction of, 48 Battery, constructing centre passage of, 48 Battery, counter, 82 Battery, definitions, 42 Battery, electric, 163-6 Battery, enfilading, 82 Battery, exposed sunken, 46 Battery for field-guns, construction of, 43 Battery for siege-guns and howitzers, 44 Battery for siege-guns, ammunition required, 44 Battery, general requirements of siege, 42 Battery, location of, 9, 75 Battery, mortar, 55 Battery of rifled mortars and howitzers, 83 Battery on sloping ground, 53 Battery, sunken, in a parallel, 51 Battery, tracing the, 47 Belfort, siege of, 71-2, 86, 104 Besieging force, bringing up and posting, 67 Besieging force, strength and composition, 70-2 Blasts, 178 Blasting and demolitions, 178-84 Blindage-frames or blinds, 156 Blinded descents or galleries, 38, 156, 170 Blinded sap, 38 Blinded sap, traverse by, 35 Blinds or screens, 45 Blockade, 1 Bombardment, 8 Bombardment, defence against, 10 Bombardment, defence during, 105 Bomb-proofs and traverses, 25, 170 Branches, 170-72 Breach, capture and crowning of, 89 Breaching batteries, 83 Breaching by mines, 176-7 Breaching galleries, 177 Breaching the scarp and counter-scarp, 88 Breaking out a full sap from a parallel, 30 Breaking out a double sap from a parallel, 33 Bridge, demolition of, 182 Bridge, floating--passage of ditch, 40 Brigade or detachment of sappers, 28 Bringing up and posting the besieging force, 67 C Camps, fortifying, 68 Camouflet, 120, 167, 171, 172 Canal locks, demolition of, 183 Capitulation, the, 109 Capture and crowning of breach, 89 Capture and crowning of covered way, 87 Cases, mining, 139-41 Chamber, definition, 119 Chamber, form and location, 160 Changing direction of double sap, 33 Changing direction of galleries, 148, 150, 154 Changing slope of galleries, 149, 155 Charge, definition, 119 Charge, excess to be used in demolitions, 184 Charge for over- or under-charged mines, 125 Charge for blasts, weight determined, 179 Charge for blasts, when tamped, 178-9 Charge for common mines, 122-4 Charge for mines, placing, 165 Charge for mines, preparing, 161 Choice of explosives, 132 Churn-drill, 178 Circular place of arms, 31 Conquered place, occupation of, 93 Common mine defined, 120 Common mine volumes and charges, 120-4 Construction of battery for field-guns, 43 Construction of battery, sunken, 48-50 Construction of central passage, 48 Construction of magazine, 60 Construction of simple trench, 20 Construction of trench by flying sap, 22 Counter-battery, 82 Cover for bomb and splinter proofs, 23-25 Cover for magazines, 58 Covered way, crowning of the, 35 Crater, definitions, 119 Crater, assumed form of, 121 Crater relation between volume and charge, 120-7 Crater radius, definition, 119 Crowning the covered way, 35 Crutch, 154 D Dampness, precautions against, 63 Defence, the, 99-111 Defence against assault, 7, 105 Defence against bombardment, 10, 105 Defence against surprise, 4 Defence, ammunition for, 101 Defence, armament for, 100 Defence by mines, 171-2 Defence, council of, 98 Defence during bombardment and assault, 105 Defence during first period, 103 Defence during second period, 106 Defence during third period, 107 Defence, garrison for, 99 Defence, journal of, 110 Defence, opening artillery fire by, 104 Defence, preliminary considerations, 98 Defence, preparations for, 101 Defence, provisions and supplies, 101 Demi-parallels, 86 Demolitions, deliberate, 180 Demolitions, hasty, 181 Descending galleries, 147 Detachment or brigade of sappers, 28 Detonation, 162 Dispositions for an assault, 5 Distribution of fuzes in charge, 161 Distance of line of investment, 70 Ditch, passage of, 37 Double sap, 32 Double sap, breaking out, from a parallel, 33 Double sap, changing direction of, 33 Double sap, execution of, 32 Drainage, 16, 24, 55, 59 Drawings, working, 151 Drill-bars and drills, 178 Dynamite, etc., 132-5 Dynamite, freezing of, 165 Dynamite, tamping, 179 E Earth auger, 138 Electric batteries, wires, and lights, 165-6 Elevated and sunken batteries, 44 Elevated magazine, 62 Embrasures, 53 Enfilading batteries, 82 Execution of double sap, 32 Execution of single sap, 28 Experimental mines, 125, 131, 133 Explosion, theory of, 120 Explosive, charge for blasts, 179 Explosive, charge for mines, 122-5 Explosive, choice of, 132-5 Explosive, expenditure of energy, 120 Explosive, freezing of, 165 Explosive, noxious gases from, 133, 158 Explosive, relative strength of, 131, 179 Explosive, tamping of, 178-9 Exposed sunken battery, 46 F False frame, 146 Field kitchens and ovens, 114 Field-level, description, 136 Field-level, use, 146, 148, 149 Filtration of water, 117 Fire, musketry, 84 Fire, opening by attack, 76 Fire, opening by defence, 104 Fire, opening from second artillery position, 83 Firing blasts, 178 Firing and loading mines, 161-6 Firing-tubes and needles, 178-9 First artillery position, 75 First parallel, 78 First period of the siege, 65 Flying sap, 20 Flying sap, construction of, 22 Fort Wagner, 86 Form and volume of crater, 121 Fortifying camps, parks, etc., 68 Frames and sheeting compared with cases, 141 Frames and sheeting, use in shafts, 139-45 Frames and sheeting, use in galleries, 145-51 Freezing of high explosives, 165 Full sap, 28 Full sap, driving of, 28 Full sap, breaking out from a parallel, 30 Fuzes, 161, 164, 166 G Galleries, blinded, 156 Galleries, change of direction of, 148, 150, 154 Galleries, change of slopes of, 149, 154 Galleries, definitions and dimensions, 119, 138 Galleries, direction in attack, 171 Galleries, distance apart, 170 Galleries, for breaching, 177 Galleries, inclined, 147-9, 155 Galleries, listening, 170 Galleries of departure, 150 Galleries, partly lined, 148 Galleries, rate of advance of, 157 Galleries, transverse, 170 Gallery linings, 139-41 Gallery with frames and sheeting, 145-51 Gallery with cases, 153-6 Garrison of place, 99 Gases generated in mines, 133, 158 General requirements of siege batteries, 42 Globe of compression defined, 120 Governor of the place, 98 Guns, field, batteries for, 43 Guns and howitzers, batteries for, 44 Guns, ammunition required, 44-57 Guns for armament, 100 Guns of first artillery position, 76 Guns, positions of, to be changed, 106 Gunpowder, amount per cubic yard, 123, 124, 178 H Hasty demolitions, 181 High explosives compared with gunpowder, 131-5 High explosives, freezing of, 165 High explosives, use in blasting, 179-80 Houses and magazines, demolition of, 181 Howitzer batteries, 44 Howitzers for vertical fire, 83 Huts and shelters, 113 Inclined galleries, 47 Infantry trenches, 104 Intrenched camp, attack upon, 91 Investment, 9, 65 Investment, distance of line of, 70-72 J Journal of the attack, 97 Journal of the defence, 110 Jumper, 178 K Kitchens and ovens, 114 L Landings, 150-1 Latrines, sinks, etc., 115 Line of investment, distance of, 70 Line of least resistance = L. L. R., 119 Listening galleries or listeners, 170-72 Loading and firing mines, 161 Location of batteries, 9, 75 Location of magazine, 58 Lodgement, 170 M Magazines, 57 Magazines, construction of, 60 Magazines, cover for, 58 Magazines, drainage of, 59 Magazines, elevated, 62 Magazines, execution of the work upon, 61 Magazines, location of, 58 Magazines, mined, 61 Magazines, precautions against dampness, 63 Maps, 151 Masks for batteries, etc., 45 Masks, air-tight, for exploring mines, 160 Maxims, Vauban’s, 94 Mine defined, 119 Mine-chamber, 160 Mine, common, 120-5 Mine, overcharged and undercharged, 120, 125, 131, 171-72 Mines of attack, 169, 171 Mines of defence, 171-2 Mines, organization of, 169 Mine tactics, 172-6 Mined magazine, 61 Mining, military, object of, 119 Miner, attaching a, 177 Miner’s bellows, 137 Miner’s candlestick, 137 Miner’s lamp, 137 Miner’s pick and shovel, 136 Miner’s rule, 122 Miner’s truck or car, 137 Mortar batteries, 55, 83 Mortars, siege, 57, 107 Musketry fire, 84 O Observatories, 54 Occupation of conquered place, 93 Opening fire, attack, 76 Opening fire, defence, 104 Opening fire from second artillery position, 83 Opening the first parallel, 80 Organization and duties of brigade of sappers, 28 Organization and tactics of mines, 169-76 Ovens and kitchens, 114 Overcharged and undercharged mines, 120, 125, 171-2 Overground approaches, 31 P Parallels, 15 Parallels, demi-, 86 Parallels, execution of, 20-3 Parallel, first, 78 Parallel, first, opening, 80 Parallel, first, advance from, 84 Parallel, second, 85 Parallel, third, etc., 86 Parallel, tracing a, 17 Parks, camps, etc., fortifying, 68 Parks and depots, 111 Partly-lined galleries, 148 Paris, siege of, 71-2 Passage, central, of battery, 48 Passage of the ditch, 37 Period, first, of siege, 65, 103 Period, second, of siege, 75, 106 Period, third, of siege, 86, 107 Pick and shovel, miner’s, 136 Pick, miner’s, distance heard, 170 Placing fuzes in charge, 164 Placing the charge, 165, 176 Plan of attack, 78 Plevna, siege of, 71, 72 Point of attack, 73 Posting besieging force, 67 Posting working parties, 18 Powder-boxes, 58 Powder for siege batteries, 44, 57 Precautions against dampness, 63 Precautions in blasting, 180 Preliminary considerations of defence, 98 Preparations for defence, 101 Preparing the charge, 161 Progress of the siege, 12 Proofs, bomb, 25 Proofs, splinter, 23, 48, 50 Provisions and supplies, 101 Push pick, 136 R Radius of explosion, 119 Radius of rupture, 120, 128, 131 Railroads, demolition of, 183 Rate of advance of galleries, 157 Rate of advance of sap, 29 Regular approaches, 12 Requirements, general, of siege batteries, 42 Returns, 150-1 Rifled mortars and howitzers, batteries of, 83 Rolling-stock, demolition of, 184 S Sand-bag fork, 13 Sap, attack by, 91 Sap, definition, 27 Sap, blinded, 35 Sap, breaking out from a parallel, 30 Sap, double, 32-3 Sap-fork, 13 Sap, flying, 20, 22 Sap, full, 28-30 Sap, shallow, 31 Sap-shield, 13, 23 Sap, traversed, 33-5 Sap, widening the, 30 Sapping, definitions, etc., 27 Sapping, former methods, 36 Scraper, 13 Screens, 45 Second artillery position, 81 Second artillery position, opening fire from, 83 Second parallel, 85 Shaft, definitions and dimensions, 119, 138 Shaft à la Boule, 156, 172 Shaft intervals, 142 Shaft linings, 139-141 Shaft mines, 172 Shaft, sinking, with cases, 152-4 Shaft, sinking, with frames and sheeting, 141-5 Shaft in a lodgement, 170 Shallow sap, 31 Shelters and huts, 113 Shield for covering ditch, 38-40 Shield for driving gallery, 147 Shovel and pick, miner’s, 136 Siege, definitions, etc., 12, 64 Siege batteries, 42-53 Siege, first period of, 65, 103 Siege, second period of, 75, 106 Siege, third period of, 86, 107 Siege, length of, 71 Siege of Belfort, Fort Wagner, Paris, Plevna, and Strasburg, 71, 86, 104 Simple trench, 20 Sinking shaft with frames and sheeting, 141-5 Sinking shaft with cases, 152-4 Sinks and latrines, 115 Slope, defined, 119 Slope-block, 137, 148 Slope, change of, 149, 155 Slope, method of fixing, 147 Squibs, 178 Splinter-proofs, 23, 48, 56 Sterilizing water, 117 Stockades, demolition of, 182 Strasburg, siege of, 71, 86 Sunken battery, 45-53 Supplies and provisions, 101 Surprise, 2 Surprise, defence against, 4 Surrender of the place, 109 T Tamping blasts, 178-9 Tamping mines, 166 Third period of siege, 86 Todleben’s rules, 173 Tools and appliances, 10, 136 Tracing approaches, 18 Tracing a battery, 47 Tracing lanterns, pickets, tapes, etc., 14 Tracing parallels, 17 Transverse galleries or transversals, 170 Traverse by blinded sap, 35 Traverse, cube, 34 Traverses, length of, 34 Traversed sap, 33 Trenches, 15 Trench cavalier, 36 Trenches, guard of the, 15 Trench, infantry, 104 Trench, simple, 20 Tunnels, demolition of, 183 U Underground warfare, 169 V Vauban’s maxims, 94 Ventilation of mines, 158-60 Vertical fire, batteries for, 83 Volume and form of craters, 121 Volume and weight of charge, 161, 181 W Wagner, Fort, siege of, 86 Walls, demolition of, 181 Water-supply, 116 Weight and volume of charge, 161, 181 Wet ditch, passage of, 38-40 Working drawings, 151 _Plate I._ _Bradley & Poates, Engr’s, N. Y._] _Plate II._ _Bradley & Poates, Engr’s, N. Y._] _Plate III._ _Bradley & Poates, Engr’s, N. Y._] _Plate IV._ _Bradley & Poates, Engr’s, N. Y._] _Plate V._ _Bradley & Poates, Engr’s, N. Y._] _Plate VI._ _Bradley & Poates, Engr’s, N. Y._] _Plate VII._ _Bradley & Poates, Engr’s, N. Y._] _Plate VIII._ _Bradley & Poates, Engr’s, N. Y._] _Plate IX._ _Bradley & Poates, Engr’s, N. Y._] _Plate X._ _Bradley & Poates, Engr’s, N. Y._] _MILITARY MINING Plate XI._ _Bradley & Poates, Engr’s, N. Y._] _MILITARY MINING Plate XII._ _Bradley & Poates, Engr’s, N. Y._] BOOKS FOR ARMY AND NAVY OFFICERS PUBLISHED BY JOHN WILEY & SONS. =ORDNANCE AND GUNNERY.= For the use of the Cadets of the U. S. Military Academy. By Captain Henry Metcalf, Ordnance Department, U. S. Army Instructor of Ordnance and Gunnery, U.S.M.A. 12mo, 500 pp., cloth, with separate atlas containing 350 cuts, $5.00 =MODERN FRENCH ARTILLERY.= The St. Chamond, De Bange, Canet and Hotchkiss systems, with Illustrations of French War Ships. 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Second and revised edition. 12mo, red cloth, $2.50 =A MANUAL FOR COURTS-MARTIAL.= Prepared by Lt. Arthur Murray, 1st Artillery, late Acting Judge Advocate-General, U. S. A. Third edition. 18mo, morocco, flap, $1.50 =CAVALRY OUT-POST DUTIES.= By F. De Brack, translated from the French (third edition, 1863) by Major Camillo C. C. Carr, 8th Cavalry, U. S. A. 18mo, morocco, flap, $2.00 =GUNNERY OF NON-COMMISSIONED OFFICERS.= Compiled by Lt. Adelbert Cronkhite, 4th Artillery, with Ballistic Tables, by Capt. James Chester, 3d Artillery, 18mo, morocco, flap, $2.00 =ART OF SUBSISTING ARMIES IN WAR.= By Capt. H. G. Sharpe, U. S. A. 18mo, cloth, $1.25 morocco, $1.50 =THE ARMY OFFICER’S EXAMINER.= By Lt. Col. W. H. Powell, U. S. A. 12mo, cloth, $4.00 =ELEMENTARY NAVAL TACTICS.= By Commander Wm. Bainbridge-Hoff, U. S. N. 8vo, cloth, (in preparation.) FOOTNOTES: [1] In the siege of Strasburg, 1870, a bridge of beer casks was built across the ditch of Lunette No. 52, between nightfall and 10 P. M., September 21st. The ditch was about 66 feet wide and 9 to 10 feet deep. This bridge gave access to the lunette. It was subsequently sunk by the fire of the work and was replaced by a causeway.--Franco-German War, Official Account, Part 2, vol. 1., pp. 88, 89. [2] One of a group of trees may frequently serve for this purpose. [3] The charge for the 5" siege gun is 15 lbs. of powder; 200 rounds = 3,000 lbs.; 2 guns, 6,000 lbs. [4] No special box has been adopted in our service. The English box is 1' 9" × 1' 5½" × 1' 5" outside, metal lined, and holds almost 100 lbs. of made-up cartridges. [5] The crater radius of a mine with L. L. R. of 6' to 12' and a charge of 6,000 lbs. of powder would be about 44 feet (Art. 7, Military Mining). The radius of the mound of earth thrown out would probably be three times this. [6] Quoted from Mahan’s Siege Operations. [7] A shell from a 9" .45 rifled mortar has in experimental firing produced in moderately hard ground a crater 8 feet deep and 19½ feet in diameter. [8] From the unpublished records of three experimental mines fired at Willet’s Point in 1877-83 it would seem that the quantities given in this table are greater than those required if good American powder is used. These mines, in a soil of modified drift, with a L. L. R. of 12 ft. required 1.02 lbs. per cu. yd. = 1 lb. ⅓ oz.; and with a L. L. R. of 17 ft. required 1.15 lbs. per cu. yd. = 1 lb. 2½ oz. [9] Six-lined craters (_r_ = 3_l_) are generally considered as the practical limit of overcharged mines, although at Chatham mines have been fired giving _r_ = (3-3/4)_l_. The published data concerning them indicate that they required charges larger than the formulas above given call for. [10] Describe the semicircle _BMNF_. Then _OD_ : _ON_ :: _CH_ : _CM_; _l_ : _ON_ :: _v_ : _h_. _ON_^2 = (_h_^2 _l_^2) / _v_^2. (1) _BO_ : _ON_ :: _ON_ : _OF_; _h_ + _r_ : _ON_ :: _ON_ : _h_ - _r_. _ON_^2 = _h_^2 - _r_^2 (2) _CF_ : _CH_ :: _CD_ : _CK_; _h_ : _v_ :: √(_r_^2 + _l_^2) : _l_. (_h_^2)(_l_^2)/_v_^2 = _r_^2 + _l_^2 (3) ∴ Eqs. (1), (2), and (3), _r_^2 + _l_^2 = _h_^2 - _r_^2. _h_^2 = _l_^2 +2_r_^2 (4) _h_ = √(1 + 2(_r_/_l_)^2). Eqs. (3) and (4), (_l_^2 + 2_r_^2)_l_^2 = _v_^2(_r_^2 + _l_^2). _v_^2 = (_l_^2 +2_r_^2)/(1+_r_^2/_l_^2) = _l_^2(1+2(_r_^2/_l_^2))/(1+_r_^2/_l_^2); _v_ = _l_(√((1+2(_r_/_l_)^2)/(1+(_r_/_l_)^2))). [11] General Abbot’s experiments in submarine mining fix the relative values of cannon powder and dynamite No. 1 in water, measured by the pressure exerted by them (not by the craters formed), as 1 : 2.45. The characters of the media and the explosives would naturally lead to the inference that the superiority of dynamite over powder would be greater in water than in earth.--J. M. [12] The 82 lb. dynamite-mine at Willet’s Point produced almost exactly the same effect upon the gallery of access as the 200-lb. cannon-powder mine, while its external crater was considerably less in diameter. Its crater was surrounded, however, by concentric cracks spaced at intervals of 3 or 4 feet to a distance of about 40 feet from the centre of the crater. No such effect was produced by the powder-mine. On the other hand, the actual radii of rupture produced by five experimental mines fired at Olmutz in 1871-2 agree very closely with the values which result from applying Lebrun’s formulas to craters of the same size and shape produced by gunpowder, and indicate that charges of dynamite and gunpowder which produce identical craters will also have identical radii of rupture. The somewhat contradictory results given by the Willet’s Point and Olmutz mines show the necessity for further experiments. [13] To pass a 5" siege-gun, mounted upon a high or “overbank” carriage (model 1887), requires a gallery 7' × 7' in clear. [14] Four of these may be unskilled laborers. [15] No. required at commencement of gallery. Beyond 4 feet add one man, and one additional for every 20 feet of gallery. [16] Instead of a truck a canvas bag may be used. A large hoe or drag may be used to draw back the earth from the face of the gallery. [17] One mason’s level. [18] These numbers are for small shafts of about 2' by 4'; large shafts require a larger force. They advance at about the same rate as galleries of equal cross-section. [19] In the blasting at Hell Gate, 1870-76, several cases occurred, both with nitro-glycerine and compressed gun-cotton, in which a part of the charge exploded, breaking the blast-hole nearly to the bottom, and leaving the remainder of the charge unexploded in the bottom of the hole, from which it was subsequently recovered. Similar results were obtained in experiments, conducted by Capt. (now Major) Heuer, 1875-6, with long tubes filled with nitro-glycerine. See also Encyc. Brit., vol. xvi, “Mining,” for similar information. [20] In compact soil the sound of a pick can be heard up to about 40 feet, and at about 20 feet when the miners are working as quietly as possible. [21] E.g., the sieges of Candia (1667-9), Schweidnitz (1762), Silistria and Brailow (1828-9), Sebastopol (1854-5), Vicksburg (1863), Petersburg (1864), etc., etc., and the experimental mining operations at Graudenz in 1862. See Woolwich and Chatham Text-books, Mahan’s Field Fortifications, Guerre de Siège Blanchecotte et Chauvot Fontainebleau, etc., etc. [22] A dynamite cartridge 1" in diameter weighs ½ lb. per running foot; 2" in diameter, 2 lbs. per ft.; etc. [23] Capt. Schaw’s (R. E.) rule for an untamped charge of gunpowder placed as above described is _C_ lbs. = ⅔ L. L. R.^2 × _B_, in which _C_ = charge in pounds, _B_ = breadth of bridge in feet, and L. L. R. = line of least resistance in feet, measured through the arch. [Transcriber’s Note: Obvious printer errors corrected silently. Inconsistent spelling and hyphenation are as in the original.] End of Project Gutenberg's Attack of Fortified Places., by James Mercur	104,883	common-pile/project_gutenberg_filtered	59253	project gutenberg	project_gutenberg-dolma-0011.json.gz:504	https://www.gutenberg.org/ebooks/59253.txt.utf-8
RuS9fCNJReEguFrU	Diverse Scientists	37 Leroy Little Bear Dr. Leroy Little Bear \| \| Time period:20th Centruy – Present Subject:Indigenous Knowledge Systems and Science (Metaphysics) \| \| Biography:Dr. Leroy Little Bear was born on the Blood Indian Reserve in Southern Alberta, a member of the Kainai First Nations, and the Blackfoot Confederacy. He grew up with six siblings and began his education at St. Mary’s Indian Residential School at 10. From a young age, Dr. Little Bear was aware of the colonial context of the school he was attending and how learning was presented from a colonial viewpoint. In the early 1970s, Leroy earned a bachelor’s degree, being one of the first Indigenous students to graduate from the University of Lethbridge. In 1975 he received a law degree from the University of Utah. Throughout his career, Dr. Little Bear was a founding member of the Native American Studies Department at the University of Lethbridge and the founding director of the Native American Program at Harvard. On top of this he had an influential role in advising the National Indian Brotherhood, Canada’s constitutional changes, the British North American Act, and treaties 6,7, and 8. He has also worked with the United Nations, forming the Declaration on the Rights of Indigenous Peoples In 1997 Dr. Little Bear retired from the University of Lethbridge, and in 2016 Leroy received an honorary Doctor of Arts and Science degree from the University of Lethbridge. He has also received the National Aboriginal Achievement Award for Education (2003) and has been inducted into the Alberta Order Excellence (2016) and the Order of Canada (2019). Although Dr. Leroy Little Bear may not be considered a traditional “scientist” by Western standards, in my mind, he is a scientist. He helps explain why the world is the way it is and seeks to bring understanding and education to all. His contributions to the world in the intersection of Indigenous Knowledge systems and Western science earn him a place in this book. \| \| Summary of their contributions:Although Dr. Leroy Little Bear has not specialized in a specific traditional scientific discipline in the Western sense, he focused more on the intersection of Indigenous knowledge systems and Western science, seeking to bridge the gap between the two. Advocating for the intersection of Indigenous Ways of Knowing and Western science, Dr. Little Bear has pointed to Blackfoot science and their metaphysics of life to incorporate Indigenous science within the Western science classroom. In one of his presentations, “Metaphysics: Intersecting Western and Native Ideas. Resilience from a Blackfoot Perspective.” Dr. Little Bear points out that Blackfoot perspectives can be applied to climate change, teaching us about reciprocity with the land we live on. His other contributions to science advocate for the recognition, validation, and integration of Indigenous knowledge systems within science as a whole. Touching on areas such as ecology, environmental science, education, philosophy, and cultural studies. Dr. Little Bear has been at the forefront of incorporating Indigenous ways of knowing into science classrooms. \| \| Integration with the BC Secondary Science Curriculum:Dr. Leroy Little Bear’s work naturally integrates with the BC secondary Science curriculum and is a great resource for any teacher who is serious about incorporating Indigenous ways of knowing into their classroom. There are First People’s ways of knowing in all the content areas of secondary science (Environmental Science, Biology, Earth Science, Physics, and Chemistry) and his work showcasing the Blackfoot perspectives and traditional ways of knowing/doing are great resources from an Indigenous individual. Specifically, we can see Dr. Little Bear being integrated with the curricular competencies in the following ways: “Apply First Peoples perspectives and knowledge, other ways of knowing, and local knowledge as sources of information.” – Dr. Little Bear’s promotion of integrating Indigenous knowledge into science classrooms, exposes children to different ways of knowing and viewing the world. He encourages connections between these diverse knowledge systems to promote a better understanding of the world we live in “Seek and analyze patterns, trends, and connections in data, including describing relationships between variables, performing calculations, and identifying inconsistencies.” – Dr. Little Bear’s emphasis on interconnectedness, and holistic views knowing science can be used to encourage students to approach data analysis and patterns with a broader mindset. Allowing students to use different perspectives to interpret data and trends and a holistic lens of understanding the relationships between variables. “Demonstrate an awareness of assumptions, question information given, and identify bias in their own work and in primary and secondary sources.” – Dr. Little Bear recognized the colonial aspect of education as early as 10 when he started his education journey at a residential school. By looking at his lived experience teachers can use what he has reflected on to deconstruct the current education system and point out areas of colonialism that still penetrate how we teach our students today. “Consider the changes in knowledge over time as tools and technologies have developed.” – Dr. Little Bear urges all to have a mindset of inclusion and respect for diverse knowledge systems that have also developed alongside the development of tools and technologies. He shares the understanding of flux from the Blackfoot perspective, pointing out that knowledge is not static, but is always changing and evolving within differing cultural contexts and through interactions with tools and technologies. “Communicate scientific ideas and information, and perhaps a suggested course of action, for a specific purpose and audience, constructing evidence-based arguments and using appropriate scientific language, conventions, and representations.” – Being an educator, Dr. Little Bear made a career out of communicating ideas and information with others. Teachers can look at Dr. Little Bear’s communicative work (interviews, speeches, books, papers) to show their students how someone integrated Indigenous ways of knowing into the communication of science ideas (for example, his work with climate change). “Express and reflect on a variety of experiences, perspectives, and worldviews through place.” – Dr. Little Bear highlights the interconnectedness between people, land, and knowledge. Sharing that there is meaning in understanding knowledge in the context of specific places. For example, Dr. Little Bear’s work with the restoration of the Buffalo population in Southern Alberta showcases the idea that the Buffalo is a keystone species within the ecosystem that is Southern Alberta. \| \| References:Building Student Success—B.C. Curriculum. (n.d.). Retrieved October 20, 2023, from https://curriculum.gov.bc.ca/curriculum/science/11/life-sciences Leroy Little Bear. (n.d.). Retrieved December 8, 2023, from https://www.thecanadianencyclopedia.ca/en/article/leroy-little-bear Leroy Little Bear \| Alberta.ca. (n.d.). Retrieved December 8, 2023, from https://www.alberta.ca/aoe-leroy-little-bear Leroy Little Bear on Blackfoot metaphysics and climate change. (2022, April 30). The Sprawl. https://www.sprawlcalgary.com/leroy-little-bear-climate-change Q&A: Little Bear offers a different view of science. (2011, March 21). ASU News. https://news.asu.edu/20230525-qa-little-bear-offers-different-view-science Leroy Little Bear (BASc (BA) ’71, DASc ’03) \| University of Lethbridge. (n.d.). Retrieved December 8, 2023, from https://www.ulethbridge.ca/alumni/awards/2003/leroy-little-bear Dr. Leroy Little Bear \| Decolonizing Water. (n.d.). Retrieved December 8, 2023, from https://decolonizingwater.ca/team/dr-leroy-little-bear/ \|	1,474	common-pile/pressbooks_filtered	https://pressbooks.bccampus.ca/diversescientiststhenandnow/chapter/167/	pressbooks	pressbooks-0000.json.gz:23308	https://pressbooks.bccampus.ca/diversescientiststhenandnow/chapter/167/
VYh4PODTwR5cRDzo	Macroeconomics	12 Interpreting Slope Learning Objectives - Differentiate between a positive relationship and a negative relationship What the Slope Means The concept of slope is very useful in economics, because it measures the relationship between two variables. A positive slope means that two variables are positively related—that is, when x increases, so does y, and when x decreases, y also decreases. Graphically, a positive slope means that as a line on the line graph moves from left to right, the line rises. We will learn in other sections that “price” and “quantity supplied” have a positive relationship; that is, firms will supply more when the price is higher. A negative slope means that two variables are negatively related; that is, when x increases, y decreases, and when x decreases, y increases. Graphically, a negative slope means that as the line on the line graph moves from left to right, the line falls. We will learn that “price” and “quantity demanded” have a negative relationship; that is, consumers will purchase less when the price is higher. A slope of zero means that y is constant no matter the value of x. Graphically, the line is flat; the rise over run is zero. The unemployment-rate graph in Figure 4, below, illustrates a common pattern of many line graphs: some segments where the slope is positive, other segments where the slope is negative, and still other segments where the slope is close to zero. Try It Calculating Slope The slope of a straight line between two points can be calculated in numerical terms. To calculate slope, begin by designating one point as the “starting point” and the other point as the “end point” and then calculating the rise over run between these two points. Try It Use the graph to find the slope of the line. Show Answer Start from a point on the line, such as [latex](2,1)[/latex] and move vertically until in line with another point on the line, such as [latex](6,3)[/latex]. The rise is 2 units. It is positive as you moved up. Next, move horizontally to the point [latex](6,3)[/latex]. Count the number of units. The run is 4 units. It is positive as you moved to the right. Then solve using the formula: [latex]\displaystyle \text{Slope }=\frac{\text{rise}}{\text{run}}[/latex] so [latex]\displaystyle \text{Slope}=\frac{2}{4}=\frac{1}{2}[/latex] Try It These next questions allow you to get as much practice as you need, as you can click the link at the top of the first question (“Try another version of these questions”) to get a new set of questions. Practice until you feel comfortable doing the questions and then move on. [ohm_question sameseed=1]92306-93504-92308[/ohm_question] Graphs of economic relationships are not always straight lines. In this course, you will often see nonlinear (curved) lines, like Figure 6, which shows the relationship between quantity of output being produced and the cost of producing that output. As the quantity of output increases, the total cost increases at a faster rate. Table 1 shows the data behind this graph. \| Table 1: Total Cost Curve \| \|\| \| Quantity of Output (Q) \| Total Cost (TC) \| \| \| 1 \| $1 \| \| \| 2 \| $4 \| \| \| 3 \| $9 \| \| \| “Point A” \| 4 \| $16 \| \| “Point B” \| 5 \| $25 \| \| 6 \| $36 \| \| \| 7 \| $49 \| \| \| 8 \| $64 \| \| \| 9 \| $81 \| \| \| 10 \| $100 \| We can interpret nonlinear relationships similarly to the way we interpret linear relationships. Their slopes can be positive or negative. We can calculate the slopes similarly also, looking at the rise over the run of a segment of a curve. As an example, consider the slope of the total cost curve, above, between points A & B. Going from point A to point B, the rise is the change in total cost (i.e. the variable on the vertical axis): $25 – $16 = $9 Similarly, the run is the change in quantity (i.e. the variable on the horizontal axis): 5 – 4 = 1 Thus, the slope of a straight line between these two points would be 9/1 = 9. In other words, as we increase the quantity of output produced by one unit, the total cost of production increases by $9. Try It Suppose the slope of a line were to increase. Graphically, that means it would get steeper. Suppose the slope of a line were to decrease. Then it would get flatter. These conditions are true whether or not the slope was positive or negative to begin with. A lower positive slope means a flatter upward tilt to the curve, which you can see in Figure 6 at low levels of output. A higher positive slope means a steeper upward tilt to the curve, which you can see at higher output levels. A negative slope that is larger in absolute value (that is, more negative) means a steeper downward tilt to the line. A slope of zero is a horizontal line. A vertical line has an infinite slope. Suppose a line has a larger intercept. Graphically, that means it would shift out (or up) from the old origin, parallel to the old line. This is shown in Figure 7, below, as the shift from the line labeled Y to the line labeled Y1. If a line has a smaller intercept, it would shift in (or down), parallel to the old line. Glossary - negative slope: - indicates that two variables are negatively related; when one variable increases, the other decreases, and when one variable decreases, the other increases - positive slope: - indicates that two variables are positively related; when one variable increases, so does the other, and when one variable decreases, the other also decreases - slope: - the change in the vertical axis divided by the change in the horizontal axis - slope of zero: - indicates that there is no relationship between two variables; when one variable changes, the other does not change	1,305	common-pile/pressbooks_filtered	https://library.achievingthedream.org/sacmacroeconomics/chapter/interpreting-slope/	pressbooks	pressbooks-0000.json.gz:81442	https://library.achievingthedream.org/sacmacroeconomics/chapter/interpreting-slope/
EgUGSeuYevAebbDS	BCIT Astronomy 7000: A Survey of Astronomy	Chapter 19 Celestial Distances 19.4 The H–R Diagram and Cosmic Distances Learning Objectives By the end of this section, you will be able to: - Understand how spectral types are used to estimate stellar luminosities - Examine how these techniques are used by astronomers today Variable stars are not the only way that we can estimate the luminosity of stars. Another way involves the H–R diagram, which shows that the intrinsic brightness of a star can be estimated if we know its spectral type. Distances from Spectral Types As satisfying and productive as variable stars have been for distance measurement, these stars are rare and are not found near all the objects to which we wish to measure distances. Suppose, for example, we need the distance to a star that is not varying, or to a group of stars, none of which is a variable. In this case, it turns out the H–R diagram can come to our rescue. If we can observe the spectrum of a star, we can estimate its distance from our understanding of the H–R diagram. As discussed in Analyzing Starlight, a detailed examination of a stellar spectrum allows astronomers to classify the star into one of the spectral types indicating surface temperature. (The types are O, B, A, F, G, K, M, L, T, and Y; each of these can be divided into numbered subgroups.) In general, however, the spectral type alone is not enough to allow us to estimate luminosity. Look again at [link]. A G2 star could be a main-sequence star with a luminosity of 1 LSun, or it could be a giant with a luminosity of 100 LSun, or even a supergiant with a still higher luminosity. We can learn more from a star’s spectrum, however, than just its temperature. Remember, for example, that we can detect pressure differences in stars from the details of the spectrum. This knowledge is very useful because giant stars are larger (and have lower pressures) than main-sequence stars, and supergiants are still larger than giants. If we look in detail at the spectrum of a star, we can determine whether it is a main-sequence star, a giant, or a supergiant. Suppose, to start with the simplest example, that the spectrum, color, and other properties of a distant G2 star match those of the Sun exactly. It is then reasonable to conclude that this distant star is likely to be a main-sequence star just like the Sun and to have the same luminosity as the Sun. But if there are subtle differences between the solar spectrum and the spectrum of the distant star, then the distant star may be a giant or even a supergiant. The most widely used system of star classification divides stars of a given spectral class into six categories called luminosity classes. These luminosity classes are denoted by Roman numbers as follows: - Ia: Brightest supergiants - Ib: Less luminous supergiants - II: Bright giants - III: Giants - IV: Subgiants (intermediate between giants and main-sequence stars) - V: Main-sequence stars The full spectral specification of a star includes its luminosity class. For example, a main-sequence star with spectral class F3 is written as F3 V. The specification for an M2 giant is M2 III. [link] illustrates the approximate position of stars of various luminosity classes on the H–R diagram. The dashed portions of the lines represent regions with very few or no stars. With both its spectral and luminosity classes known, a star’s position on the H–R diagram is uniquely determined. Since the diagram plots luminosity versus temperature, this means we can now read off the star’s luminosity (once its spectrum has helped us place it on the diagram). As before, if we know how luminous the star really is and see how dim it looks, the difference allows us to calculate its distance. (For historical reasons, astronomers sometimes call this method of distance determination spectroscopic parallax, even though the method has nothing to do with parallax.) The H–R diagram method allows astronomers to estimate distances to nearby stars, as well as some of the most distant stars in our Galaxy, but it is anchored by measurements of parallax. The distances measured using parallax are the gold standard for distances: they rely on no assumptions, only geometry. Once astronomers take a spectrum of a nearby star for which we also know the parallax, we know the luminosity that corresponds to that spectral type. Nearby stars thus serve as benchmarks for more distant stars because we can assume that two stars with identical spectra have the same intrinsic luminosity. A Few Words about the Real World Introductory textbooks such as ours work hard to present the material in a straightforward and simplified way. In doing so, we sometimes do our students a disservice by making scientific techniques seem too clean and painless. In the real world, the techniques we have just described turn out to be messy and difficult, and often give astronomers headaches that last long into the day. For example, the relationships we have described such as the period-luminosity relation for certain variable stars aren’t exactly straight lines on a graph. The points representing many stars scatter widely when plotted, and thus, the distances derived from them also have a certain built-in scatter or uncertainty. The distances we measure with the methods we have discussed are therefore only accurate to within a certain percentage of error—sometimes 10%, sometimes 25%, sometimes as much as 50% or more. A 25% error for a star estimated to be 10,000 light-years away means it could be anywhere from 7500 to 12,500 light-years away. This would be an unacceptable uncertainty if you were loading fuel into a spaceship for a trip to the star, but it is not a bad first figure to work with if you are an astronomer stuck on planet Earth. Nor is the construction of H–R diagrams as easy as you might think at first. To make a good diagram, one needs to measure the characteristics and distances of many stars, which can be a time-consuming task. Since our own solar neighborhood is already well mapped, the stars astronomers most want to study to advance our knowledge are likely to be far away and faint. It may take hours of observing to obtain a single spectrum. Observers may have to spend many nights at the telescope (and many days back home working with their data) before they get their distance measurement. Fortunately, this is changing because surveys like Gaia will study billions of stars, producing public datasets that all astronomers can use. Despite these difficulties, the tools we have been discussing allow us to measure a remarkable range of distances—parallaxes for the nearest stars, RR Lyrae variable stars; the H–R diagram for clusters of stars in our own and nearby galaxies; and cepheids out to distances of 60 million light-years. [link] describes the distance limits and overlap of each method. Each technique described in this chapter builds on at least one other method, forming what many call the cosmic distance ladder. Parallaxes are the foundation of all stellar distance estimates, spectroscopic methods use nearby stars to calibrate their H–R diagrams, and RR Lyrae and cepheid distance estimates are grounded in H–R diagram distance estimates (and even in a parallax measurement to a nearby cepheid, Delta Cephei). This chain of methods allows astronomers to push the limits when looking for even more distant stars. Recent work, for example, has used RR Lyrae stars to identify dim companion galaxies to our own Milky Way out at distances of 300,000 light-years. The H–R diagram method was recently used to identify the two most distant stars in the Galaxy: red giant stars way out in the halo of the Milky Way with distances of almost 1 million light-years. We can combine the distances we find for stars with measurements of their composition, luminosity, and temperature—made with the techniques described in Analyzing Starlight and The Stars: A Celestial Census. Together, these make up the arsenal of information we need to trace the evolution of stars from birth to death, the subject to which we turn in the chapters that follow. \| Distance Range of Celestial Measurement Methods \| \| \|---\|---\| \| Method \| Distance Range \| \| Trigonometric parallax \| 4–30,000 light-years when the Gaia mission is complete \| \| RR Lyrae stars \| Out to 300,000 light-years \| \| H–R diagram and spectroscopic distances \| Out to 1,200,000 light-years \| \| Cepheid stars \| Out to 60,000,000 light-years \| Key Concepts and Summary Stars with identical temperatures but different pressures (and diameters) have somewhat different spectra. Spectral classification can therefore be used to estimate the luminosity class of a star as well as its temperature. As a result, a spectrum can allow us to pinpoint where the star is located on an H–R diagram and establish its luminosity. This, with the star’s apparent brightness, again yields its distance. The various distance methods can be used to check one against another and thus make a kind of distance ladder which allows us to find even larger distances. For Further Exploration Articles Adams, A. “The Triumph of Hipparcos.” Astronomy (December 1997): 60. Brief introduction. Dambeck, T. “Gaia’s Mission to the Milky Way.” Sky & Telescope (March 2008): 36–39. An introduction to the mission to measure distances and positions of stars with unprecedented accuracy. Hirshfeld, A. “The Absolute Magnitude of Stars.” Sky & Telescope (September 1994): 35. Good review of how we measure luminosity, with charts. Hirshfeld, A. “The Race to Measure the Cosmos.” Sky & Telescope (November 2001): 38. On parallax. Trefil, J. Puzzling Out Parallax.” Astronomy (September 1998): 46. On the concept and history of parallax. Turon, C. “Measuring the Universe.” Sky & Telescope (July 1997): 28. On the Hipparcos mission and its results. Zimmerman, R. “Polaris: The Code-Blue Star.” Astronomy (March 1995): 45. On the famous cepheid variable and how it is changing. Websites ABCs of Distance: http://www.astro.ucla.edu/~wright/distance.htm. Astronomer Ned Wright (UCLA) gives a concise primer on many different methods of obtaining distances. This site is at a higher level than our textbook, but is an excellent review for those with some background in astronomy. American Association of Variable Star Observers (AAVSO): https://www.aavso.org/. This organization of amateur astronomers helps to keep track of variable stars; its site has some background material, observing instructions, and links. Friedrich Wilhelm Bessel: http://messier.seds.org/xtra/Bios/bessel.html. A brief site about the first person to detect stellar parallax, with references and links. Gaia: http://sci.esa.int/gaia/. News from the Gaia mission, including images and a blog of the latest findings. Hipparchos: http://sci.esa.int/hipparcos/. Background, results, catalogs of data, and educational resources from the Hipparchos mission to observe parallaxes from space. Some sections are technical, but others are accessible to students. John Goodricke: The Deaf Astronomer: http://www.bbc.com/news/magazine-20725639. A biographical article from the BBC. Women in Astronomy: http://www.astrosociety.org/education/astronomy-resource-guides/women-in-astronomy-an-introductory-resource-guide/. More about Henrietta Leavitt’s and other women’s contributions to astronomy and the obstacles they faced. Videos Gaia’s Mission: Solving the Celestial Puzzle: https://www.youtube.com/watch?v=oGri4YNggoc. Describes the Gaia mission and what scientists hope to learn, from Cambridge University (19:58). Hipparcos: Route Map to the Stars: https://www.youtube.com/watch?v=4d8a75fs7KI. This ESA video describes the mission to measure parallax and its results (14:32) How Big Is the Universe: https://www.youtube.com/watch?v=K_xZuopg4Sk. Astronomer Pete Edwards from the British Institute of Physics discusses the size of the universe and gives a step-by-step introduction to the concepts of distances (6:22) Search for Miss Leavitt: http://perimeterinstitute.ca/videos/search-miss-leavitt., Video of talk by George Johnson on his search for Miss Leavitt (55:09). Women in Astronomy: http://www.youtube.com/watch?v=5vMR7su4fi8. Emily Rice (CUNY) gives a talk on the contributions of women to astronomy, with many historical and contemporary examples, and an analysis of modern trends (52:54). Collaborative Group Activities - In this chapter, we explain the various measurements that have been used to establish the size of a standard meter. Your group should discuss why we have changed the definitions of our standard unit of measurement in science from time to time. What factors in our modern society contribute to the growth of technology? Does technology “drive” science, or does science “drive” technology? Or do you think the two are so intertwined that it’s impossible to say which is the driver? - Cepheids are scattered throughout our own Milky Way Galaxy, but the period-luminosity relation was discovered from observations of the Magellanic Clouds, a satellite galaxy now known to be about 160,000 light-years away. What reasons can you give to explain why the relation was not discovered from observations of cepheids in our own Galaxy? Would your answer change if there were a small cluster in our own Galaxy that contained 20 cepheids? Why or why not? - You want to write a proposal to use the Hubble Space Telescope to look for the brightest cepheids in galaxy M100 and estimate their luminosities. What observations would you need to make? Make a list of all the reasons such observations are harder than it first might appear. - Why does your group think so many different ways of naming stars developed through history? (Think back to the days before everyone connected online.) Are there other fields where things are named confusingly and arbitrarily? How do stars differ from other phenomena that science and other professions tend to catalog? - Although cepheids and RR Lyrae variable stars tend to change their brightness pretty regularly (while they are in that stage of their lives), some variable stars are unpredictable or change their their behavior even during the course of a single human lifetime. Amateur astronomers all over the world follow such variable stars patiently and persistently, sending their nightly observations to huge databases that are being kept on the behavior of many thousands of stars. None of the hobbyists who do this get paid for making such painstaking observations. Have your group discuss why they do it. Would you ever consider a hobby that involves so much work, long into the night, often on work nights? If observing variable stars doesn’t pique your interest, is there something you think you could do as a volunteer after college that does excite you? Why? - In [link], the highest concentration of stars occurs in the middle of the main sequence. Can your group give reasons why this might be so? Why are there fewer very hot stars and fewer very cool stars on this diagram? - In this chapter, we discuss two astronomers who were differently abled than their colleagues. John Goodricke could neither hear nor speak, and Henrietta Leavitt struggled with hearing impairment for all of her adult life. Yet they each made fundamental contributions to our understanding of the universe. Does your group know people who are handling a disability? What obstacles would people with different disabilities face in trying to do astronomy and what could be done to ease their way? For a set of resources in this area, see http://astronomerswithoutborders.org/gam2013/programs/1319-people-with-disabilities-astronomy-resources.html. Review Questions 1: Explain how parallax measurements can be used to determine distances to stars. Why can we not make accurate measurements of parallax beyond a certain distance? 2: Suppose you have discovered a new cepheid variable star. What steps would you take to determine its distance? 3: Explain how you would use the spectrum of a star to estimate its distance. 4: Which method would you use to obtain the distance to each of the following? - An asteroid crossing Earth’s orbit - A star astronomers believe to be no more than 50 light-years from the Sun - A tight group of stars in the Milky Way Galaxy that includes a significant number of variable stars - A star that is not variable but for which you can obtain a clearly defined spectrum 5: What are the luminosity class and spectral type of a star with an effective temperature of 5000 K and a luminosity of 100 LSun? Thought Questions 6: The meter was redefined as a reference to Earth, then to krypton, and finally to the speed of light. Why do you think the reference point for a meter continued to change? 7: While a meter is the fundamental unit of length, most distances traveled by humans are measured in miles or kilometers. Why do you think this is? 8: Most distances in the Galaxy are measured in light-years instead of meters. Why do you think this is the case? 9: The AU is defined as the average distance between Earth and the Sun, not the distance between Earth and the Sun. Why does this need to be the case? 10: What would be the advantage of making parallax measurements from Pluto rather than from Earth? Would there be a disadvantage? 11: Parallaxes are measured in fractions of an arcsecond. One arcsecond equals 1/60 arcmin; an arcminute is, in turn, 1/60th of a degree (°). To get some idea of how big 1° is, go outside at night and find the Big Dipper. The two pointer stars at the ends of the bowl are 5.5° apart. The two stars across the top of the bowl are 10° apart. (Ten degrees is also about the width of your fist when held at arm’s length and projected against the sky.) Mizar, the second star from the end of the Big Dipper’s handle, appears double. The fainter star, Alcor, is about 12 arcmin from Mizar. For comparison, the diameter of the full moon is about 30 arcmin. The belt of Orion is about 3° long. Keeping all this in mind, why did it take until 1838 to make parallax measurements for even the nearest stars? 12: For centuries, astronomers wondered whether comets were true celestial objects, like the planets and stars, or a phenomenon that occurred in the atmosphere of Earth. Describe an experiment to determine which of these two possibilities is correct. 13: The Sun is much closer to Earth than are the nearest stars, yet it is not possible to measure accurately the diurnal parallax of the Sun relative to the stars by measuring its position relative to background objects in the sky directly. Explain why. 14: Parallaxes of stars are sometimes measured relative to the positions of galaxies or distant objects called quasars. Why is this a good technique? 15: Estimating the luminosity class of an M star is much more important than measuring it for an O star if you are determining the distance to that star. Why is that the case? 16: [link] is the light curve for the prototype cepheid variable Delta Cephei. How does the luminosity of this star compare with that of the Sun? 17: Which of the following can you determine about a star without knowing its distance, and which can you not determine: radial velocity, temperature, apparent brightness, or luminosity? Explain. 18: A G2 star has a luminosity 100 times that of the Sun. What kind of star is it? How does its radius compare with that of the Sun? 19: A star has a temperature of 10,000 K and a luminosity of 10–2LSun. What kind of star is it? 20: What is the advantage of measuring a parallax distance to a star as compared to our other distance measuring methods? 21: What is the disadvantage of the parallax method, especially for studying distant parts of the Galaxy? 22: Luhman 16 and WISE 0720 are brown dwarfs, also known as failed stars, and are some of the new closest neighbors to Earth, but were only discovered in the last decade. Why do you think they took so long to be discovered? 23: Most stars close to the Sun are red dwarfs. What does this tell us about the average star formation event in our Galaxy? 24: Why would it be easier to measure the characteristics of intrinsically less luminous cepheids than more luminous ones? 25: When Henrietta Leavitt discovered the period-luminosity relationship, she used cepheid stars that were all located in the Large Magellanic Cloud. Why did she need to use stars in another galaxy and not cepheids located in the Milky Way? Figuring for Yourself 26: A radar astronomer who is new at the job claims she beamed radio waves to Jupiter and received an echo exactly 48 min later. Should you believe her? Why or why not? 27: The New Horizons probe flew past Pluto in July 2015. At the time, Pluto was about 32 AU from Earth. How long did it take for communication from the probe to reach Earth, given that the speed of light in km/hr is 1.08 × 109? 28: Estimate the maximum and minimum time it takes a radar signal to make the round trip between Earth and Venus, which has a semimajor axis of 0.72 AU. 29: The Apollo program (not the lunar missions with astronauts) being conducted at the Apache Point Observatory uses a 3.5-m telescope to direct lasers at retro-reflectors left on the Moon by the Apollo astronauts. If the Moon is 384,472 km away, approximately how long do the operators need to wait to see the laser light return to Earth? 30: In 1974, the Arecibo Radio telescope in Puerto Rico was used to transmit a signal to M13, a star cluster about 25,000 light-years away. How long will it take the message to reach M13, and how far has the message travelled so far (in light-years)? Demonstrate that 1 pc equals 3.09 × 1013 km and that it also equals 3.26 light-years. Show your calculations. The best parallaxes obtained with Hipparcos have an accuracy of 0.001 arcsec. If you want to measure the distance to a star with an accuracy of 10%, its parallax must be 10 times larger than the typical error. How far away can you obtain a distance that is accurate to 10% with Hipparcos data? The disk of our Galaxy is 100,000 light-years in diameter. What fraction of the diameter of the Galaxy’s disk is the distance for which we can measure accurate parallaxes? Astronomers are always making comparisons between measurements in astronomy and something that might be more familiar. For example, the Hipparcos web pages tell us that the measurement accuracy of 0.001 arcsec is equivalent to the angle made by a golf ball viewed from across the Atlantic Ocean, or to the angle made by the height of a person on the Moon as viewed from Earth, or to the length of growth of a human hair in 10 sec as seen from 10 meters away. Use the ideas in [link] to verify one of the first two comparisons. Gaia will have greatly improved precision over the measurements of Hipparcos. The average uncertainty for most Gaia parallaxes will be about 50 microarcsec, or 0.00005 arcsec. How many times better than Hipparcos (see [link]) is this precision? Using the same techniques as used in [link], how far away can Gaia be used to measure distances with an uncertainty of 10%? What fraction of the Galactic disk does this correspond to? The human eye is capable of an angular resolution of about one arcminute, and the average distance between eyes is approximately 2 in. If you blinked and saw something move about one arcmin across, how far away from you is it? (Hint: You can use the setup in [link] as a guide.) How much better is the resolution of the Gaia spacecraft compared to the human eye (which can resolve about 1 arcmin)? The most recently discovered system close to Earth is a pair of brown dwarfs known as Luhman 16. It has a distance of 6.5 light-years. How many parsecs is this? What would the parallax of Luhman 16 (see [link]) be as measured from Earth? The New Horizons probe that passed by Pluto during July 2015 is one of the fastest spacecraft ever assembled. It was moving at about 14 km/s when it went by Pluto. If it maintained this speed, how long would it take New Horizons to reach the nearest star, Proxima Centauri, which is about 4.3 light-years away? (Note: It isn’t headed in that direction, but you can pretend that it is.) What physical properties are different for an M giant with a luminosity of 1000 LSun and an M dwarf with a luminosity of 0.5 LSun? What physical properties are the same? Glossary - luminosity class - a classification of a star according to its luminosity within a given spectral class; our Sun, a G2V star, has luminosity class V, for example	5,281	common-pile/pressbooks_filtered	https://pressbooks.bccampus.ca/a7000y2018/chapter/19-4-the-h-r-diagram-and-cosmic-distances/	pressbooks	pressbooks-0000.json.gz:75072	https://pressbooks.bccampus.ca/a7000y2018/chapter/19-4-the-h-r-diagram-and-cosmic-distances/
jk6NCkJwrCysxN6_	4.6: Volcanoes in British Columbia	4.6: Volcanoes in British Columbia As shown on the Figure $\PageIndex{1}$, three types of volcanic environments are represented in British Columbia: - The Cascade Arc (a.k.a. the Garibaldi Volcanic Belt in Canada) is related to subduction of the Juan de Fuca Plate beneath the North America plate. This extends along the south coast from the U.S. border to the northern end of Vancouver Island. - The Anahim Volcanic Belt is assumed to be related to a mantle plume. It is in central BC and stretches inland from the coast. - The Stikine Volcanic Belt (northwestern BC) and the Wells Gray-Clearwater Volcanic Field (central Alberta border area) are assumed to be related to crustal rifting. Subduction Volcanism Southwestern British Columbia is at the northern end of the Juan de Fuca (Cascadia) subduction zone, and the volcanism there is related to magma generation by flux melting in the upper mantle above the subducting plate. In general, there has been a much lower rate and volume of volcanism in the B.C. part of this belt than in the U.S. part. One possible reason for this is that the northern part of the Juan de Fuca Plate (i.e., the Explorer Plate) is either not subducting, or is subducting at a slower rate than the rest of the plate. There are several volcanic centres in the Garibaldi Volcanic Belt: the Garibaldi centre (including Mount Garibaldi and the Black Tusk-Mount Price area adjacent to Garibaldi Lake (Figures 4.0.1 and 4.0.2), Mount Cayley, and Mount. Meager (Figure $\PageIndex{3}$). The most recent volcanic activity in this area was at Mount Meager. Approximately 2,400 years ago, an explosive eruption of about the same magnitude as the 1980 Mount St. Helens eruption took place at Mount Meager. Ash spread as far east as Alberta. There was also significant eruptive activity at Mounts Price and Garibaldi approximately 12,000 and 10,000 years ago during the last glaciation; in both cases, lava and tephra built up against glacial ice in the adjacent valley (Figure $\PageIndex{2}$). The Table in Figure $\PageIndex{2}$ at the beginning of this chapter is a tuya , a volcano that formed beneath glacial ice and had its top eroded by the lake that formed around it in the ice. Mantle Plume Volcanism The chain of volcanic complexes and cones extending from Milbanke Sound to Nazko Cone is interpreted as being related to a mantle plume currently situated close to the Nazko Cone, just west of Quesnel. The North America Plate is moving in a westerly direction at about 2 cm per year with respect to this plume, and the series of now partly eroded shield volcanoes between Nazco and the coast is interpreted to have been formed by the plume as the continent moved over it. The Rainbow Range, which formed at approximately 8 Ma, is the largest of these older volcanoes. It has a diameter of about 30 km and an elevation of 2,495 m (Figure $\PageIndex{3}$). The name “Rainbow” refers to the bright colors displayed by some of the volcanic rocks as they weather. Rift-Related Volcanism While B.C. is not about to split into pieces, two areas of volcanism are related to rifting—or at least to stretching-related fractures that might extend through the crust. These are the Wells Gray-Clearwater volcanic field southeast of Quesnel, and the Northern Cordillera Volcanic Field, which ranges across the northwestern corner of the province (as already discussed in section 4.1). This area includes Canada’s most recent volcanic eruption, a cinder cone and mafic lava flow that formed around 250 years ago at the Tseax River Cone in the Nass River area north of Terrace. According to Nisga’a oral history, as many as 2,000 people died during that eruption, in which lava overran their village on the Nass River. Most of the deaths are attributed to asphyxiation from volcanic gases, probably carbon dioxide. The Mount Edziza Volcanic Field near the Stikine River is a large area of lava flows, sulfurous ridges, and cinder cones. The most recent eruption in this area was about 1,000 years ago. While most of the other volcanism in the Edziza region is mafic and involves lava flows and cinder cones, Mount Edziza itself (Figure $\PageIndex{4}$) is a composite volcano with rock compositions ranging from rhyolite to basalt. A possible explanation for the presence of composite volcanism in an area dominated by mafic flows and cinder cones is that there is a magma chamber beneath this area, within which magma differentiation is taking place. This map shows the plate tectonic situation in the area around New Zealand. - Based on what you know about volcanoes in B.C., predict where you might expect to see volcanoes in and around New Zealand. - What type of volcanoes would you expect to find in and around New Zealand? See Appendix 3 for Exercise 4.7 Answers . Media Attributions - Figure $\PageIndex{1}$: “South-West Canada” by USGS. Public domain. Volcanic locations from Wood, D. (1993). Waiting for another big blast – probing B.C.’s volcanoes, Canadian Geographic, based on the work of Cathie Hickson. - Figure $\PageIndex{2}$: Photo from Google Earth. © Google. Edited by Steven Earle. Used with permission. - Figure $\PageIndex{3}$: “ Rainbow Range Colors ” © nass5518 . CC BY. - Figure $\PageIndex{4}$: “ Mount Edziza, British Columbia ” © nass5518 . CC BY. - Figure $\PageIndex{5}$: “ NZ Faults ” © Mikenorton . CC BY-SA.	1,160	common-pile/libretexts_filtered	https://geo.libretexts.org/Bookshelves/Geology/Physical_Geology_(Earle)/04%3A_Volcanism/4.06%3A_Volcanoes_in_British_Columbia	libretexts	libretexts-0000.json.gz:48049	https://geo.libretexts.org/Bookshelves/Geology/Physical_Geology_(Earle)/04%3A_Volcanism/4.06%3A_Volcanoes_in_British_Columbia
hTiBBEyH8pdSOI6h	Fundamentals of Nursing Pharmacology - Mohawk College Edition	Nursing Fundamentals Nursing Fundamentals Nursing Fundamentals Nursing Fundamentals Nursing Fundamentals by Chippewa Valley Technical College is licensed under a Creative Commons Attribution 4.0 International License, except where otherwise noted. Introduction 1 This Nursing Fundamentals textbook is an open educational resource with CC-BY licensing developed for entry-level nursing students. Content is based on the Wisconsin Technical College System (WTCS) statewide nursing curriculum for the Nursing Fundamentals course (543-101), the 2019 NCLEX-RN Test Plan,NCSBN. (n.d.). 2019 NCLEX-RN test plan. https://www.ncsbn.org/2019_RN_TestPlan-English.htm the 2020 NCLEX-PN Test Plan,NCSBN. (2019). NCLEX-PN Examination: Test plan for the national council licensure examination for practical nurses. https://www.ncsbn.org/2020_NCLEXPN_TestPlan-English.pdf and the Wisconsin Nurse Practice Act.Wisconsin State Legislature. (2018). Chapter 6: Standards of practice for registered nurses and licensed practical nurses. Board of Nursing. https://docs.legis.wisconsin.gov/statutes/statutes/441 This book introduces the entry-level nursing student to the scope of nursing practice, various communication techniques, and caring for diverse patients. The nursing process is used as a framework for providing patient care based on the following nursing concepts: safety, oxygenation, comfort, spiritual well-being, grief and loss, sleep and rest, mobility, nutrition, fluid and electrolyte imbalance, and elimination. Care for patients with integumentary disorders and cognitive or sensory impairments is also discussed. Learning activities have been incorporated into each chapter to encourage students to use critical thinking while applying content to patient care situations. The Open Resources for Nursing (Open RN) project is supported by a $2.5 million grant from the Department of Education. This book is available for free online and can also be downloaded in multiple formats for offline use. The online version is required for interaction with adaptive learning activities included in each chapter. Affordable print versions may also be purchased from XanEdu in college bookstores and on Amazon. The following video provides a quick overview of how to navigate the online version. Preface 2 This Nursing Fundamentals textbook is an open educational resource with a CC-BY 4.0 license developed for entry-level prelicensure nursing students. Content is based on the Wisconsin Technical College System (WTCS) statewide nursing curriculum for the Nursing Fundamentals course (543-101), the 2019 NCLEX-RN Test Plan,NCSBN. (n.d.). 2019 NCLEX-RN test plan.https://www.ncsbn.org/2019_RN_TestPlan-English.htm the 2020 NCLEX-PN Test Plan,NCSBN. (2019). NCLEX-PN Examination: Test plan for the national council licensure examination for practical nurses.https://www.ncsbn.org/2020_NCLEXPN_TestPlan-English.pdf and the Wisconsin Nurse Practice Act.Wisconsin State Legislature. (2018). Chapter 6: Standards of practice for registered nurses and licensed practical nurses. Board of Nursing. https://docs.legis.wisconsin.gov/statutes/statutes/441 The project is supported by a $2.5 million Open Resources for Nursing (Open RN) grant from the Department of Education to create five free, open source nursing textbooks. However, this content does not necessarily represent the policy of the Department of Education, and you should not assume endorsement by the federal government. More information about the Open RN grant can be found at cvtc.edu/OpenRN. The first textbook of the Open RN textbook series, Nursing Pharmacology, received an OE Award for Excellence from OE Global. For more information, visit the 2020 OE Awards for Excellence site. Usage Survey and Feedback We would love to hear if you have integrated some or all of this resource into your course. Please use this short survey to report student usage information every semester that is reported to the Department of Education. Please use this survey to provide constructive feedback or report any errors. About this Book Editors - Kimberly Ernstmeyer, MSN, RN, CNE, CHSE, APNP-BC - Dr. Elizabeth Christman, DNP, RN, CNE Graphics Editor - Nic Ashman, MLIS, Librarian, Chippewa Valley Technical College Developing Authors Developing authors remixed existing open educational resources and developed new content based on evidence-based sources: - Leeann Anthon, MSN, RN, CNE, Madison Area Technical College - Dr. Lisa Blohm, PhD, RN, Northeast Wisconsin Technical College - Barbara Brown, MSN, RN, Moraine Park Technical College - Dr. Elizabeth Christman, DNP, RN, CNE, Chippewa Valley Technical College/Southern New Hampshire University - Tami Davis, MSN, RN, Chippewa Valley Technical College - Kim Ernstmeyer, MSN, RN, CNE, CHSE, APNP-BC, Chippewa Valley Technical College - Dr. Allison Nicol, PhD, RN, CNE, Milwaukee Area Technical College - Dr. Valerie Palarski, EdD, MSN/ED, RN, Northcentral Technical College - Lynda Rastall, MSN, RN, CNE, Northeast Wisconsin Technical College - Julie Sigler, MSN, RN, Chippewa Valley Technical College Contributors Contributors assisted in the creation of this textbook: - Jane Flesher, MST, Proofreader, Chippewa Valley Technical College - Deanna Hoyord, Paramedic (retired), Human Patient Simulation Technician and Photographer, Chippewa Valley Technical College - Theresa Meinen, MS, RRT, CHSE, Director of Clinical Education – Respiratory Therapy Program, Chippewa Valley Technical College - Vince Mussehl, MLIS, Open RN Lead Librarian, Chippewa Valley Technical College - Joshua Myers, Web Developer, Chippewa Valley Technical College - Meredith Pomietlo, Retail Design and Marketing Student, UW-Stout - Lauren Richards, Graphics Designer, Chippewa Valley Technical College - Celee Schuch, Nursing Student, St. Catherine University - Christina Sima, MSN, RN, Gateway Community College - Dominic Slauson, Technology Professional Developer, Chippewa Valley Technical College - Dr. Jamie Zwicky, EdD, MSN, RN, Moraine Park Technical College Advisory Committee The Open RN Advisory Committee consists of industry members and nursing deans and provides input for the Open RN textbooks and virtual reality scenarios: - Jenny Bauer, MSN, RN, NPD-BC, Mayo Clinic Health System Northwest Wisconsin, Eau Claire, WI - Gina Bloczynski, MSN, RN, Dean of Nursing, Chippewa Valley Technical College - Angela Branum, Western Wisconsin Health - Lisa Cannestra, Eastern Wisconsin Healthcare Alliance - Travis Christman, MSN, RN, Clinical Director, HSHS Sacred Heart and St. Joseph’s Hospitals - Sheri Johnson, UW Population Health Institute - Dr. Vicki Hulback, DNP, RN, Dean of Nursing, Gateway Technical College - Jenna Julson, MSN, RN, NPD-BC, Nursing Education Specialist, Mayo Clinic Health System Northwest Wisconsin, Eau Claire, WI - Brian Krogh, MSN, RN, Associate Dean – Health Sciences, Northeast Wisconsin Technical College - Hugh Leasum, MBA, MSN, RN, Nurse Manager Cardiology/ICU, Marshfield Clinic Health System, Eau Claire, WI - Pam Maxwell, SSM Health - Mari Kay-Nobozny, NW Wisconsin Workforce Development Board - Dr. Amy Olson, DNP, RN, Nursing Education Specialist, Mayo Clinic Health System Northwest Wisconsin, Eau Claire, WI - Rorey Pritchard, EdS, MEd, MSN, RN-BC, CNOR(E), CNE, Senior RN Clinical Educator, Allevant Solutions, LLC - Kelly Shafaie, MSN, RN, Associate Dean of Nursing, Moraine Park Technical College - Dr. Ernise Watson, PhD, RN, Associate Dean of Nursing, Madison Area Technical College - Sherry Willems, HSHS St. Vincent Hospital Reviewers - Emily Adams, MSN, RN, CNE, Arizona Western College - Ava Alden, Nursing Student, St. Catherine University - Dr. Caryn Aleo, PhD, RN, CCRN, CEN, CNEcl, NPD-BC, Pasco-Hernando State College - Dr. Kimberly A. 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Rosemeyer, MSN, RN, Chippewa Valley Technical College - Callie Schlegel, Nursing Student, St. Catherine University - Celee Schuch, Nursing Students, St. Catherine University - Chassity Speight-Washburn, MSN, RN, CNE, Stanly Community College - Dr. Carmen Stephens, DNP, RN, MS, University of Colorado-Anschutz Medical Campus - Dr. Suzanne H. Tang, DNP, MSN, APRN, FNP-BC, PHN, Rio Hondo College - Forum Tihara, MSN, RN, Madison Area Technical College - Jacquelyn R. Titus, MS, RN, Pasco Hernando State College - Amy L. Tyznik, MSN, RN, Moraine Park Technical College - Heidi VandenBush, MSN, RN-BC, Northeast Wisconsin Technical College - Jennie E. Ver Steeg, MA, MS, MLS, Mercy College of Health Sciences - Dr. Nancy Lynn Whitehead, PhD, APNP, RN, Milwaukee Area Technical College - Dr. LaDonna Williams, DNP, RN, Lord Fairfax Community College - Julie Woitalla, MSN, RN, Central Lakes College Licensing/Terms of Use This textbook is licensed under a Creative Commons Attribution 4.0 International (CC-BY) license unless otherwise indicated, which means that you are free to: - SHARE – copy and redistribute the material in any medium or format - ADAPT – remix, transform, and build upon the material for any purpose, even commercially The licensor cannot revoke these freedoms as long as you follow the license terms. - Attribution: You must give appropriate credit, provide a link to the license, and indicate if any changes were made. 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For specific reference information about what was used and/or changed in this adaptation, please refer to the footnotes at the bottom of each page of the book. - Nursing Pharmacology by Chippewa Valley Technical College is licensed under CC BY 4.0. - Nursing Skills by Chippewa Valley Technical College is licensed under CC BY 4.0. - Anatomy and Physiology by Boundless is licensed under CC BY-SA 4.0. - Anatomy & Physiology by OpenStax is licensed under CC BY 4.0. - Anatomy and Physiology by Rice University is licensed under CC BY 4.0. - Clinical Procedures for Safer Care by British Columbia Institute of Technology is licensed under CC BY 4.0. - The Complete Subjective Health Assessment by Lapum, St-Amant, Hughes, Petrie, Morrell, and Mistry is licensed under CC BY 4.0. - Concepts of Biology – 1st Canadian Edition by Molnar & Gair is licensed under CC BY 4.0. - Human Biology by Wakim and Grewal is licensed under CC-BY-NC 4.0. - Human Relations by LibreTexts is licensed under CC BY-NC-SA. - Human Development Life Span by Overstreet is licensed under CC BY 4.0. - Human Nutrition by University of Hawai’i at Mānoa Food Science and Human Nutrition Program is licensed under CC BY 4.0. - Introduction to Sociology by OpenStax is licensed under CC BY 4.0. - Microbiology by OpenStax is licensed under CC BY 4.0. - Nursing Care at the End of Life by Lowey is licensed under CC BY-NC-SA 4.0. - The Scholarship of Writing in Nursing Education: 1st Canadian Edition by Lapum, St-Amant, Hughes, Tan, Bogdan, Dimaranan, Frantzke, and Savicevic is licensed under CC BY-SA 4.0. - StatPearls by StatPearls Publishing is licensed under CC BY 4.0. Content that is not taken from the above OER or public domain should include the following attribution statement: Ernstmeyer, K., & Christman, E. (Eds.). (2021). Open RN Nursing Fundamentals by Chippewa Valley Technical College is licensed under CC BY 4.0. Standards & Conceptual Approach 3 The Open RN Nursing Fundamentals textbook is based on several external standards and uses a conceptual approach. External Standards American Nurses Association (ANA): The ANA provides standards for professional nursing practice including nursing standards and a code of ethics for nurses. The National Council Licensure Examination for Registered Nurses: NCLEX-PN and NCLEX-RN Test Plans The NCLEX-RN and NCLEX-PN test plans are updated every three years to reflect fair, comprehensive, current, and entry-level nursing competency. The National League of Nursing (NLN): Competencies for Graduates of Nursing Programs NLN competencies guide nursing curricula to position graduates in a dynamic health care arena with practice that is informed by a body of knowledge and ensures that all members of the public receive safe, quality care. Quality and Safety Education for Nurses (QSEN) Institute: Pre-licensure Competencies Quality and safety competencies include knowledge, skills, and attitudes to be developed in nursing pre-licensure programs. QSEN competencies include patient-centered care, teamwork and collaboration, evidence-based practice, quality improvement, safety, and informatics. Wisconsin State Legislature, Administrative Code Chapter N6 The Wisconsin Administrative Code governs the Registered Nursing and Practical Nursing professions in Wisconsin. Healthy People 2030 Healthy People 2030 envisions a society in which all people can achieve their full potential for health and well-being across the life span. Healthy People provides objectives based on national data and includes social determinants of health. Conceptual Approach The Open RN Nursing Fundamentals textbook incorporates the following concepts across all chapters: - Holism. Florence Nightingale taught nurses to focus on the principles of holism, including wellness and the interrelationship of human beings and their environment. This textbook encourages the application of holism by assessing the impact of developmental, emotional, cultural, religious, and spiritual influences on a patient’s health status. - Evidence-Based Practice (EBP). Textbook content is based on current, evidence-based practices that are referenced by footnotes. To promote digital literacy, hyperlinks are provided to credible, free online resources that supplement content. The Open RN textbooks will be updated as new EBP is established and with the release of updated NCLEX Test Plans every three years. - Cultural Competency. Nurses have an ethical and moral obligation to provide culturally competent care to the patients they serve based on the ANA Code of Ethics.American Nurses Association. (2015). Code of ethics for nurses with interpretive statements. American Nurses Association. https://www.nursingworld.org/practice-policy/nursing-excellence/ethics/code-of-ethics-for-nurses/ Cultural considerations are included throughout this textbook. - Care Across the Life Span. Developmental stages are addressed regarding patient assessments and procedures. - Health Promotion. Focused interview questions and patient education topics are included to promote patient well-being and encourage self-care behaviors. - Scope of Practice. Assessment techniques are included that have been identified as frequently performed by entry-level nurse generalists.Anderson, B., Nix, E., Norman, B., & McPike, H. D. (2014). An evidence based approach to undergraduate physical assessment practicum course development. Nurse Education in Practice, 14(3), 242–246. https://doi.org/10.1016/j.nepr.2013.08.007,Giddens, J., & Eddy, L. (2009). A survey of physical examination skills taught in undergraduate nursing programs: Are we teaching too much? Journal of Nursing Education, 48(1), 24–29. https://doi.org/10.3928/01484834-20090101-05,Giddens, J. (2007). A survey of physical assessment techniques performed by RNs: Lessons for nursing education. Journal of Nursing Education, 46(2), 83–87. https://doi.org/10.3928/01484834-20070201-09,Morrell, S., Ralph, J., Giannotti, N., Dayus, D., Dennison, S., & Bornais, J.(2019). Physical assessment skills in nursing curricula: A scoping review protocol. JBI Database System Rev Implement Rep., 17(6), 1086-1091. https://doi.org/10.11124/jbisrir-2017-003981. - Patient Safety. Expected and unexpected findings on assessment are highlighted in tables to promote patient safety by encouraging notification of health care providers when changes in condition occur. - Clear and Inclusive Language. Content is written using clear language preferred by entry-level pre-licensure nursing students to enhance understanding of complex concepts.Verkuyl, M., Lapum, J., St-Amant, O., Bregstein, J., & Hughes, M. (2020). Healthcare students’ use of an e-textbook open educational resource on vital sign measurement: A qualitative study. Open Learning: The Journal of Open, Distance and e-Learning. https://doi.org/10.1080/02680513.2020.1835623 “They” is used as a singular pronoun to refer to a person whose gender is unknown or irrelevant to the context of the usage, as endorsed by APA style. It is inclusive of all people and helps writers avoid making assumptions about gender.American Psychological Association (2021). Singular “They.” https://apastyle.apa.org/style-grammar-guidelines/grammar/singular-they - Open Source Images and Fair Use. Images are included to promote visual learning. Students and faculty can reuse open source images by following the terms of their associated Creative Commons licensing. Some images are included based on Fair Use as described in the “Code of Best Practices for Fair Use and Fair Dealing in Open Education” presented at the OpenEd20 conference. Refer to the footnotes of images for source and licensing information throughout the text. - Open Pedagogy. Students are encouraged to contribute to the Open RN textbooks in meaningful ways. In this textbook, students assisted in reviewing content for clarity for an entry-level learner and also assisted in creating open source images.The Open Pedagogy Notebook by Steel Wagstaff is licensed under CC BY 4.0 Supplementary Material Provided Several supplementary resources are provided with this textbook. - Supplementary, free videos to promote student understanding of concepts and procedures - Sample documentation for assessments and procedures - Online learning activities with formative feedback - Critical thinking questions that encourage application of content to patient scenarios - Free downloadable versions for offline use An affordable print version of this textbook is published by XanEdu and is available on Amazon and in college bookstores. It has been reported that over 65% of students prefer a print version of their textbooks.Verkuyl, M., Lapum, J., St-Amant, O., Bregstein, J., & Hughes, M. (2020). Healthcare students’ use of an e-textbook open educational resource on vital sign measurement: A qualitative study. Open Learning: The Journal of Open, Distance and e-Learning. https://doi.org/10.1080/02680513.2020.1835623 Scope of Practice I 1.1. Scope of Practice Introduction Open Resources for Nursing (Open RN) Learning Objectives - Discuss nursing scope of practice and standards of care - Compare various settings in which nurses work - Describe contributions of interprofessional health care team members - Describe levels of nursing education and the NCLEX - Discuss basic legal considerations and ethics - Outline professional nursing organizations - Examine quality and evidence-based practice in nursing You are probably wondering, “What is scope of practice? What does it mean for me and my nursing practice?” Scope of practice is defined as services that a trained health professional is deemed competent to perform and permitted to undertake according to the terms of their professional nursing license.American Nurses Association. (n.d.). Scope of practice. https://www.nursingworld.org/practice-policy/scope-of-practice/ Nursing scope of practice provides a framework and structured guidance for activities one can perform based on their nursing license. As a nurse and a nursing student, is always important to consider: Just because your employer asks you to do a task…can you perform this task according to your scope of practice – or are you putting your nursing license at risk? Nurses must also follow legal standards in when providing nursing care. Standards are set by several organizations, including the American Nurses Association (ANA), your state’s Nurse Practice Act, agency policies and procedures, and federal regulators. These standards assure safe, competent care is provided to the public. This chapter will provide an overview of basic concepts related to nursing scope of practice and standards of care. 1.2 History and Foundation Open Resources for Nursing (Open RN) Brief History of Nursing Before discussing scope and standards of nursing care, it is helpful to briefly review a history of the nursing profession. Florence Nightingale is considered to be the founder of modern nursing practice. In 1860 she established the first nursing school in the world. By establishing this school of nursing, Nightingale promoted the concept of nurses as a professional, educated workforce of caregivers for the sick.Karimi, H., & Masoudi Alavi, N. (2015). Florence Nightingale: The mother of nursing. Nursing and Midwifery Studies, 4(2), e29475. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4557413/ See Figure 1.1“Florence Nightingale (H Hering NPG x82368).jpg” by Henry Hering (1814-1893) is in the Public Domain for a portrait of Florence Nightingale. Florence Nightingale’s contributions to health care started during the Crimean War in 1854. Her team discovered that poor health care for wounded soldiers was being delivered by overworked medical staff in a dirty environment. Florence recorded the mortality rate in the hospital and created statistical models that demonstrated that out of every 1,000 injured soldiers, 600 were dying because of preventable communicable and infectious diseases. Florence’s nursing interventions were simple; she focused on providing a clean environment, clean water, and good nutrition to promote healing, such as providing fruit as part of the care for the wounded soldiers. With these simple actions, the mortality rate of the soldiers decreased from 60% to 2.2%. In 1859 Nightingale wrote a book titled Notes on Nursing that served as the cornerstone of the Nightingale School of Nursing curriculum. Nightingale believed in the importance of placing a patient in a environment that promoted healing where they could recover from disease. She promoted this knowledge as distinct from medical knowledge. Her emphasis on the value of the environment formed many of the foundational principles that we still use in creating a healing health care setting today. She also insisted on the importance of building trusting relationships with patients and believed in the therapeutic healing that resulted from nurses’ presence with patients. She promoted the concept of confidentiality, stating a nurse “should never answer questions about her sick except to those who have a right to ask them.”Karimi, H., & Masoudi Alavi, N. (2015). Florence Nightingale: The mother of nursing. Nursing and Midwifery Studies, 4(2), e29475. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4557413/. These nursing concepts formed the foundation of nursing practice as we know it today. Modern nursing has reinvented itself a number of times as health care has advanced and changed over the past 160 years. With more than four million members, the nursing profession represents the largest segment of the United States’ health care workforce. Nursing practice covers a broad continuum, including health promotion, disease prevention, coordination of care, and palliative care when cure is not possible. Nurses directly affect patient care and provide the majority of patient assessments, evaluations, and care in hospitals, nursing homes, clinics, schools, workplaces, and ambulatory settings. They are at the front lines in ensuring that patient care is delivered safely, effectively, and compassionately. Additionally, nurses attend to patients and their families in a holistic way that often goes beyond physical health needs and recognize social, mental, emotional, and spiritual needs.Institute of Medicine (US) Committee on the Robert Wood Johnson Foundation Initiative on the Future of Nursing, at the Institute of Medicine. (2011). The future of nursing: Leading change, advancing health. National Academies Press. https://www.ncbi.nlm.nih.gov/books/NBK209880/57413/ American Nurses Association (ANA) The American Nurses Association (ANA) is a national, professional nursing organization that was established in 1896. The ANA represents the interests of nurses in all 50 states of America while also promoting improved health care for everyone. The mission of the ANA is to “lead the profession to shape the future of nursing and health care.”American Nurses Association. (n.d.). About ANA. https://www.nursingworld.org/ana/about-ana/ The ANA states that it exists to advance the nursing profession by doing the following: - Fostering high standards of nursing practice - Promoting a safe and ethical work environment - Bolstering the health and wellness of nurses - Advocating on health care issues that affect nurses and the publicAmerican Nurses Association. (n.d.). About ANA. https://www.nursingworld.org/ana/about-ana/ The ANA sets many standard of care for professional nurses that will be discussed in the next section. Read more information about the American Nurses Association View the Discover the American Nurses Association video.American Nurses Association. (2010, May 14). Discover the American Nurses Association (ANA). [Video]. YouTube. All rights reserved. https://youtu.be/PRwPhOjeqL4 1.3 Regulations & Standards Open Resources for Nursing (Open RN) Standards for nursing care are set by several organizations, including the American Nurses Association (ANA), your state’s Nurse Practice Act, agency policies and procedures, federal regulators, and other professional nursing organizations. These standards assure safe, competent care is provided to the public. ANA Scope and Standards of Practice The American Nurses Association (ANA) publishes two resources that set standards and guide professional nursing practice in the United States: The Code of Ethics for Nurses and Nursing: Scope and Standards of Practice. The Code of Ethics for Nurses establishes an ethical framework for nursing practice across all roles, levels, and settings. It is discussed in greater detail in the “Legal Considerations and Ethics” subsection of this chapter. The Nursing: Scope and Standards of Practice describes a professional nurse’s scope of practice and defines the who, what, where, when, why, and how of nursing. It also sets 18 standards of professional practice that all registered nurses are expected to perform competently. American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association The “who” of nursing practice are the nurses who have been educated, titled, and maintain active licensure to practice nursing. The “what” of nursing is the recently revised definition of nursing: “Nursing integrates the art and science of caring and focuses on the protection, promotion, and optimization of health and human functioning; prevention of illness and injury; facilitation of healing; and alleviation of suffering through compassionate presence. Nursing is the diagnosis and treatment of human responses and advocacy in the care of individuals, families, groups, communities, and populations in recognition of the connection of all humanity.”American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association Simply put, nurses treat human responses to health problems and life processes and advocate for the care of others. Nursing practice occurs “when” there is a need for nursing knowledge, wisdom, caring, leadership, practice, or education, anytime, anywhere. Nursing practice occurs in any environment “where” there is a health care consumer in need of care, information, or advocacy. The “why” of nursing practice is described as nursing’s response to the changing needs of society to achieve positive health care consumer outcomes in keeping with nursing’s social contract and obligation to society. The “how” of nursing practice is defined as the ways, means, methods, and manners that nurses use to practice professionally.American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association The “how” of nursing is further defined by the standards of practice set by the ANA. There are two sets of standards, the Standards of Professional Nursing Practice and the Standards of Professional Performance. The Standards of Professional Nursing Practice are “authoritative statements of the actions and behaviors that all registered nurses, regardless of role, population, specialty, and setting, are expected to perform competently.”American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association These standards define a competent level of nursing practice based on the critical thinking model known as the nursing process. The nursing process includes the components of assessment, diagnosis, outcomes identification, planning, implementation, and evaluation.American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. Each of these standards is further discussed in the “Nursing Process” chapter of this book. The Standards of Professional Performance are 12 additional standards that describe a nurse’s professional behavior, including activities related to ethics, advocacy, respectful and equitable practice, communication, collaboration, leadership, education, scholarly inquiry, quality of practice, professional practice evaluation, resource stewardship, and environmental health. All registered nurses are expected to engage in these professional role activities based on their level of education, position, and role. Registered nurses are accountable for their professional behaviors to themselves, health care consumers, peers, and ultimately to society. American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. The 2021 Standards of Professional Performance are as follows: - Ethics. The registered nurse integrates ethics in all aspects of practice. - Advocacy. The registered nurse demonstrates advocacy in all roles and settings. - Respectful and Equitable Practice. The registered nurse practices with cultural humility and inclusiveness. - Communication. The registered nurse communicates effectively in all areas of professional practice. - Collaboration. The registered nurse collaborates with the health care consumer and other key stakeholders. - Leadership. The registered nurse leads within the profession and practice setting. - Education. The registered nurse seeks knowledge and competence that reflects current nursing practice and promotes futuristic thinking. - Scholarly Inquiry. The registered nurse integrates scholarship, evidence, and research findings into practice. - Quality of Practice. The registered nurse contributes to quality nursing practice. - Professional Practice Evaluation. The registered nurse evaluates one’s own and others’ nursing practice. - Resource Stewardship. The registered nurse utilizes appropriate resources to plan, provide, and sustain evidence-based nursing services that are safe, effective, financially responsible, and judiciously used. - Environmental Health. The registered nurse practices in a manner that advances environmental safety and health.American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. Years ago, nurses were required to recite the Nightingale pledge to publicly confirm their commitment to maintain the profession’s high ethical and moral values: “I will do all in my power to maintain and elevate the standard of my profession and will hold in confidence all personal matters committed to my keeping and family affairs coming to my knowledge in the practice of my calling, with loyalty will I endeavor to aid the physician in his work, and devote myself to the welfare of those committed to my care.” Although some of the words are outdated, the meaning is clear: Nursing is a calling, not just a job; to answer that call, you must be dedicated to serve your community according to the ANA standards of care and code of ethics.Bostain, L. (2020, June 25). Nursing professionalism begins with you. American Nurse. https://www.myamericannurse.com/nursing-professionalism-begins-with-you/ Nurse Practice Act In addition to the professional standards of practice and professional performance set by the American Nurses Association, nurses must legally follow regulations set by the Nurse Practice Act and enforced by the Board of Nursing in the state where they are employed. The Board of Nursing is the state-specific licensing and regulatory body that sets standards for safe nursing care and issues nursing licenses to qualified candidates, based on the Nurse Practice Act enacted by that state’s legislature. The Nurse Practice Act establishes regulations for nursing practice within that state and defines the scope of nursing practice. If nurses do not follow the standards and scope of practice set forth by the Nurse Practice Act, they can have their nursing license revoked by the Board of Nursing. To read more about the the Wisconsin Board of Nursing, Standards of Practice, and Rules of Conduct, use the hyperlinked PDFs provided below.Wisconsin Administrative Code. (2018). Chapter N 6 standards of practice for registered nurses and licensed practical nurses. https://docs.legis.wisconsin.gov/code/admin_code/n/6.pdf Read more details about the Wisconsin Administrative Code and the Board of Nursing. Read about Wisconsin Standards of Practice for Nurses in Chapter N 6. Read about Wisconsin Rules of Conduct in Chapter N 7. Nursing students must understand their scope of practice outlined in their state’s Nurse Practice Act. Nursing students are legally accountable for the quality of care they provide to patients just as nurses are accountable. Students are expected to recognize the limits of their knowledge and experience and appropriately alert individuals in authority regarding situations that are beyond their competency. A violation of the standards of practice constitutes unprofessional conduct and can result in the Board of Nursing denying a license to a nursing graduate. Employer Policies, Procedures, and Protocols In addition to professional nursing standards set by the American Nurses Association and the state Nurse Practice Act where they work, nurses and nursing students must also practice according to agency policies, procedures, and protocols. For example, hospitals often set a policy that requires a thorough skin assessment must be completed and documented daily on every patient. If a nurse did not follow this policy and a patient developed a pressure injury, the nurse could be held liable. In addition, every agency has their own set of procedures and protocols that a nurse and nursing student must follow. For example, each agency has specific procedural steps for performing nursing skills, such as inserting urinary catheters. A protocol is defined by the Wisconsin Nurse Practice Act as a “precise and detailed written plan for a regimen of therapy.” For example, agencies typically have a hypoglycemia protocol that nurses automatically implement when a patient’s blood sugar falls below a specific number. The hypoglycemia protocol includes actions such as providing orange juice and rechecking the blood sugar. These agency-specific policies, procedures, and protocols supersede the information taught in nursing school, and nurses and nursing students can be held legally liable if they don’t follow them. Therefore, it is vital for nurses and nursing students to always review and follow current agency-specific procedures, policies, and protocols when providing patient care. Nurses and nursing students must continue to follow their scope of practice as defined by the Nurse Practice Act in the state they are practicing when following agency policies, procedures, and protocols. Situations have occurred when a nurse or nursing student was asked by an agency to do something outside their defined scope of practice that impaired their nursing license. It is always up to you to protect your nursing license and follow the state’s Nurse Practice Act when providing patient care. Federal Regulations In addition to nursing scope of practice and standards being defined by the American Nurses Association, state Nurse Practice Acts, and employer policies, procedures, and protocols, nursing practice is also influenced by federal regulations enacted by agencies such as the Joint Commission and the Centers for Medicare and Medicaid. The Joint Commission The Joint Commission is a national organization that accredits and certifies over 20,000 health care organizations in the United States. The mission of The Joint Commission (TJC) is to continuously improve health care for the public by inspiring health care organizations to excel in providing safe and effective care of the highest quality and value.The Joint Commission. (n.d.). https://www.jointcommission.org/ The Joint Commission sets standards for providing safe, high-quality health care. National Patient Safety Goals The Joint Commission establishes annual National Patient Safety Goals for various types of agencies based on data regarding current national safety concerns.The Joint Commission. (n.d.). National patient safety goals. https://www.jointcommission.org/standards/national-patient-safety-goals/ For example, National Patient Safety Goals for hospitals include the following: - Identify Patients Correctly - Improve Staff Communication - Use Medicines Safely - Use Alarms Safely - Prevent Infection - Identify Patient Safety Risks - Prevent Mistakes in Surgery Nurses, nursing students, and other staff members are expected to incorporate actions related to these safety goals into their daily patient care. For example, SBAR (Situation, Background, Assessment, and Recommendation) handoff reporting techniques, bar code scanning equipment, and perioperative team “time-outs” prior to surgery are examples of actions incorporated at agencies based on National Patient Safety Goals. Nursing programs also use National Patient Safety Goals to guide their curriculum and clinical practice expectations. National Patient Safety Goals are further discussed in the “Safety” chapter of this book. Use the hyperlinks provided below to read more about The Joint Commission and National Patient Safety Goals. Joint Commission Center for Transforming Healthcare The Joint Commission Center for Transforming Healthcare was developed in 2008 to help agencies develop effective solutions for critical safety problems with a goal to ultimately achieve zero harm to patients. Some of the projects the Center has developed include improved hand hygiene, effective handoff communications, and safe and effective use of insulin. The Center has also been instrumental in creating a focus on a safety culture in health care organizations. A safety culture empowers nurses, nursing students, and other staff members to speak up about their concerns about patient risks and to report errors and near misses, all of which drive improvement in patient care and reduce the incidences of patient harm.Joint Commission Center for Transforming Healthcare. (n.d.). Creating a safety culture. https://www.centerfortransforminghealthcare.org/why-work-with-us/video-resources/creating-a-safety-culture Many health care agencies have implemented a safety culture in their workplace and successfully reduced incidences of patient harm. An example of a safety culture action is a nurse or nursing student creating an incident report when an error occurs when administering medication. The incident report is used by the agency to investigate system factors that contribute to errors. To read more about creating a safety culture, use the hyperlink provided below. Read more about Creating a Safety Culture. Centers for Medicare & Medicaid Services The Centers for Medicare & Medicaid Services (CMS) is another federal agency that establishes regulations that affect nursing care. CMS is a part of the U.S. Department of Health and Human Services (HHS) that administers the Medicare program and works in partnership with state governments to administer Medicaid. The CMS establishes and enforces regulations to protect patient safety in hospitals that receive Medicare and Medicaid funding. For example, one CMS regulation states that a hospital’s policies and procedures must require confirmation of specific information before medication is administered to patients. This CMS regulation is often referred to as “checking the rights of medication administration.” You can read more information about checking the rights of medication administration in the “Administration of Enteral Medications” chapter of the Open RN Nursing Skills textbook.This work is a derivative of Nursing Skills by Open RN and is licensed under CC BY 4.0 CMS also enforces quality standards in health care organizations that receive Medicare and Medicaid funding. These organizations are reimbursed based on the quality of their patient outcomes. For example, organizations with high rates of healthcare-associated infections (HAI) receive less reimbursement for services they provide. As a result, many agencies have reexamined their policies, procedures, and protocols to promote optimal patient outcomes and maximum reimbursement. Now that we have discussed various agencies that affect a nurse’s scope and standards of practice, let’s review various types of health care settings where nurses work and members of the health care team. 1.4 Health Care Settings & Team Open Resources for Nursing (Open RN) Health Care Settings There are several levels of health care including primary, secondary, and tertiary care. Each of these levels focuses on different aspects of health care and is typically provided in different settings. Primary Care Primary care promotes wellness and prevents disease. This care includes health promotion, education, protection (such as immunizations), early disease screening, and environmental considerations. Settings providing this type of health care include physician offices, public health clinics, school nursing, and community health nursing. Secondary care Secondary care occurs when a person has contracted an illness or injury and requires medical care. Secondary care is often referred to as acute care. Secondary care can range from uncomplicated care to repair a small laceration or treat a strep throat infection to more complicated emergent care such as treating a head injury sustained in an automobile accident. Whatever the problem, the patient needs medical and nursing attention to return to a state of health and wellness. Secondary care is provided in settings such as physician offices, clinics, urgent care facilities, or hospitals. Specialized units include areas such as burn care, neurosurgery, cardiac surgery, and transplant services. Tertiary Care Tertiary care addresses the long-term effects from chronic illnesses or conditions with the purpose to restore a patient’s maximum physical and mental function. The goal of tertiary care is to achieve the highest level of functioning possible while managing the chronic illness. For example, a patient who falls and fractures their hip will need secondary care to set the broken bones, but may need tertiary care to regain their strength and ability to walk even after the bones have healed. Patients with incurable diseases, such as dementia, may need specialized tertiary care to provide support they need for daily functioning. Tertiary care settings include rehabilitation units, assisted living facilities, adult day care, skilled nursing units, home care, and hospice centers. Health Care Team No matter the setting, quality health care requires a team of health care professionals collaboratively working together to deliver holistic, individualized care. Nursing students must be aware of the roles and contributions of various health care team members. The health care team consists of health care providers, nurses (licensed practical nurses, registered nurses, and advanced registered nurses), unlicensed assistive personnel, and a variety of interprofessional team members. Health Care Providers The Wisconsin Nurse Practice Act defines a provider as, “A physician, podiatrist, dentist, optometrist, or advanced practice nurse.”Wisconsin Administrative Code. (2018). Chapter N 6 standards of practice for registered nurses and licensed practical nurses. https://docs.legis.wisconsin.gov/code/admin_code/n/6.pdf Providers are responsible for ordering diagnostic tests such as blood work and X-rays, diagnosing a patient’s medical condition, developing a medical treatment plan, and prescribing medications. In a hospital setting, the medical treatment plan developed by a provider is communicated in the “History and Physical” component of the patient’s medical record with associated prescriptions (otherwise known as “orders”). Prescriptions or “orders” include diagnostic and laboratory tests, medications, and general parameters regarding the care that each patient is to receive. Nurses should respectfully clarify prescriptions they have questions or concerns about to ensure safe patient care. Providers typically visit hospitalized patients daily in what is referred to as “rounds.” It is helpful for nurses and nursing students to attend provider rounds for their assigned patients to be aware of and provide input regarding the current medical treatment plan, seek clarification, or ask questions. This helps to ensure that the provider, nurse, and patient have a clear understanding of the goals of care and minimize the need for follow-up phone calls. Nurses There are three levels of nurses as defined by each state’s Nurse Practice Act: Licensed Practical Nurse/Vocational Nurse (LPN/LVN), Registered Nurse (RN), and Advanced Practice Nurse (APRN). Licensed Practical/Vocational Nurses The NCSBN defines a licensed practical nurse (LPN) as, “An individual who has completed a state-approved practical or vocational nursing program, passed the NCLEX-PN examination, and is licensed by a state board of nursing to provide patient care.”NCSBN. https://www.ncsbn.org/ In some states, the term licensed vocational nurse (LVN) is used. LPN/LVNs typically work under the supervision of a registered nurse, advanced practice registered nurse, or physician.NCSBN. https://www.ncsbn.org/index.htm LPNs provide “basic nursing care” and work with stable and/or chronically ill populations. Basic nursing care is defined by the Wisconsin Nurse Practice Act as “care that can be performed following a defined nursing procedure with minimal modification in which the responses of the patient to the nursing care are predictable.”Wisconsin Administrative Code. (2018). Chapter N 6 standards of practice for registered nurses and licensed practical nurses. https://docs.legis.wisconsin.gov/code/admin_code/n/6.pdf LPN/LVNs typically collect patient assessment information, administer medications, and perform nursing procedures according to their scope of practice in that state. The Open RN Nursing Skills textbook discusses the skills and procedures that LPNs frequently perform in Wisconsin. See the following box for additional details about the scope of practice of the Licensed Practical Nurse in Wisconsin. Scope of Practice for Licensed Practical Nurses in Wisconsin The Wisconsin Nurse Practice Act defines the scope of practice for Licensed Practical Nurses as the following: “In the performance of acts in basic patient situations, the LPN shall, under the general supervision of an RN or the direction of a provider: (a) Accept only patient care assignments which the LPN is competent to perform. (b) Provide basic nursing care. (c) Record nursing care given and report to the appropriate person changes in the condition of a patient. (d) Consult with a provider in cases where an LPN knows or should know a delegated act may harm a patient. (e) Perform the following other acts when applicable: - Assist with the collection of data. - Assist with the development and revision of a nursing care plan. - Reinforce the teaching provided by an RN provider and provide basic health care instruction. - Participate with other health team members in meeting basic patient needs.”Wisconsin Administrative Code. (2018). Chapter N 6 standards of practice for registered nurses and licensed practical nurses. https://docs.legis.wisconsin.gov/code/admin_code/n/6.pdf Registered Nurses The NCSBN defines a Registered Nurse as “An individual who has graduated from a state-approved school of nursing, passed the NCLEX-RN examination and is licensed by a state board of nursing to provide patient care.”NCSBN. https://www.ncsbn.org/index.htm Registered Nurses (RNs) use the nursing process as a critical thinking model as they make decisions and use clinical judgment regarding patient care. The nursing process is discussed in more detail in the “Nursing Process” chapter of this book. RNs may be delegated tasks from providers or may delegate tasks to LPNs and UAPs with supervision. See the following box for additional details about the scope of practice for Registered Nurses in the state of Wisconsin. Scope of Practice for Registered Nurses in Wisconsin (1) GENERAL NURSING PROCEDURES. An RN shall utilize the nursing process in the execution of general nursing procedures in the maintenance of health, prevention of illness or care of the ill. The nursing process consists of the steps of assessment, planning, intervention, and evaluation. This standard is met through performance of each of the following steps of the nursing process: (a) Assessment. Assessment is the systematic and continual collection and analysis of data about the health status of a patient culminating in the formulation of a nursing diagnosis. (b) Planning. Planning is developing a nursing plan of care for a patient, which includes goals and priorities derived from the nursing diagnosis. (c) Intervention. Intervention is the nursing action to implement the plan of care by directly administering care or by directing and supervising nursing acts delegated to LPNs or less skilled assistants. (d) Evaluation. Evaluation is the determination of a patient’s progress or lack of progress toward goal achievement, which may lead to modification of the nursing diagnosis. (2) PERFORMANCE OF DELEGATED ACTS. In the performance of delegated acts, an RN shall do all of the following: (a) Accept only those delegated acts for which there are protocols or written or verbal orders. (b) Accept only those delegated acts for which the RN is competent to perform based on his or her nursing education, training or experience. (c) Consult with a provider in cases where the RN knows or should know a delegated act may harm a patient. (d) Perform delegated acts under the general supervision or direction of provider. (3) SUPERVISION AND DIRECTION OF DELEGATED ACTS. In the supervision and direction of delegated acts, an RN shall do all of the following: (a) Delegate tasks commensurate with educational preparation and demonstrated abilities of the person supervised. (b) Provide direction and assistance to those supervised. (c) Observe and monitor the activities of those supervised. (d) Evaluate the effectiveness of acts performed under supervision.Wisconsin Administrative Code. (2018). Chapter N 6 standards of practice for registered nurses and licensed practical nurses. https://docs.legis.wisconsin.gov/code/admin_code/n/6.pdf Advanced Practice Nurses Advanced Practice Nurses (APRN) are defined by the NCSBN as an RN who has a graduate degree and advanced knowledge. There are four categories of Advanced Practice Nurses: certified nurse-midwife (CNM), clinical nurse specialist (CNS), certified nurse practitioner (CNP), and certified registered nurse anesthetist (CRNA). APRNs can diagnose illnesses and prescribe treatments and medications. Additional information about advanced nursing degrees and roles is provided in the box below. Advanced Practice Nursing RolesInstitute of Medicine (US) Committee on the Robert Wood Johnson Foundation Initiative on the Future of Nursing at the Institute of Medicine. (2011). The future of nursing: Leading change, advancing health. National Academies Press. https://www.nap.edu/catalog/12956/the-future-of-nursing-leading-change-advancing-health Nurse Practitioners: Nurse practitioners (NPs) work in a variety of settings and complete physical examinations, diagnose and treat common acute illness and manage chronic illness, order laboratory and diagnostic tests, prescribe medications and other therapies, provide health teaching and supportive counseling with an emphasis on prevention of illness and health maintenance, and refer patients to other health professionals and specialists as needed. In many states, NPs can function independently and manage their own clinics, whereas in other states physician supervision is required. NP certifications include, but are not limited to, Family Practice, Adult-Gerontology Primary Care and Acute Care, and Psychiatric/Mental Health. To read more about NP certification, visit Nursing World’s Our Certifications web page. Clinical Nurse Specialists: Clinical Nurse Specialists (CNS) practice in a variety of health care environments and participate in mentoring other nurses, case management, research, designing and conducting quality improvement programs, and serving as educators and consultants. Specialty areas include, but are not limited to, Adult/Gerontology, Pediatrics, and Neonatal. To read more about CNS certification, visit NACNS’s What is a CNS? web page. Certified Registered Nurse Anesthetists: Certified Registered Nurse Anesthetists (CRNAs) administer anesthesia and related care before, during, and after surgical, therapeutic, diagnostic, and obstetrical procedures, as well as provide airway management during medical emergencies. CRNAs deliver more than 65 percent of all anesthetics to patients in the United States. Practice settings include operating rooms, dental offices, and outpatient surgical centers. To read more about CRNA certification, visit NBCRNA’s website. Certified Nurse Midwives: Certified Nurse Midwives provide gynecological exams, family planning advice, prenatal care, management of low-risk labor and delivery, and neonatal care. Practice settings include hospitals, birthing centers, community clinics, and patient homes. To read more about CNM certification, visit AMCB Midwife’s website. Unlicensed Assistive Personnel Unlicensed Assistive Personnel (UAP) are defined by the NCSBN as, “Any unlicensed person, regardless of title, who performs tasks delegated by a nurse. This includes certified nursing aides/assistants (CNAs), patient care assistants (PCAs), patient care technicians (PCTs), state tested nursing assistants (STNAs), nursing assistants-registered (NA/Rs), or certified medication aides/assistants (MA-Cs). Certification of UAPs varies between jurisdictions.”NCSBN. https://www.ncsbn.org/index.htm CNAs, PCAs, and PCTs in Wisconsin generally work in hospitals and long-term care facilities and assist patients with daily tasks such as bathing, dressing, feeding, and toileting. They may also collect patient information such as vital signs, weight, and input/output as delegated by the nurse. The RN remains accountable that delegated tasks have been completed and documented by the UAP. Interprofessional Team Members Nurses, as the coordinator of a patient’s care, continuously review the plan of care to ensure all contributions of the multidisciplinary team are moving the patient toward expected outcomes and goals. The roles and contributions of interprofessional health care team members are further described in the following box. Interprofessional Team Member RolesBurke, A. (2020, January 15). Collaboration with interdisciplinary team: NCLEX-RN. RegisteredNursing.org. https://www.registerednursing.org/nclex/collaboration-interdisciplinary-team/#collaborating-healthcare-members-disciplines-providing-client-care Dieticians: Dieticians assess, plan, implement, and evaluate interventions including those relating to dietary needs of those patients who need regular or therapeutic diets. They also provide dietary education and work with other members of the health care team when a client has dietary needs secondary to physical disorders such as dysphagia. Occupational Therapists (OT): Occupational therapists assess, plan, implement, and evaluate interventions, including those that facilitate the patient’s ability to achieve their highest possible level of independence in their activities of daily living such as bathing, grooming, eating, and dressing. They also provide patients adaptive devices such as long shoe horns so the patient can put their shoes on, sock pulls so they can independently pull on socks, adaptive silverware to facilitate independent eating, grabbers so the patient can pick items up from the floor, and special devices to manipulate buttoning so the person can dress and button their clothing independently. Occupational therapists also assess the home for safety and the need for assistive devices when the patient is discharged home. They may recommend modifications to the home environment such as ramps, grab rails, and handrails to ensure safety and independence. Like physical therapists, occupational therapists practice in all health care environments including the home, hospital, and rehabilitation centers. Pharmacists: Pharmacists ensure the safe prescribing and dispensing of medication and are a vital resource for nurses with questions or concerns about medications they are administering to patients. Pharmacists ensure that patients not only get the correct medication and dosing, but also have the guidance they need to use the medication safely and effectively. Physical Therapists (PT): Physical therapists are licensed health care professionals who assess, plan, implement, and evaluate interventions including those related to the patient’s functional abilities in terms of their strength, mobility, balance, gait, coordination, and joint range of motion. They supervise prescribed exercise activities according to a patient’s condition and also provide and teach patients how to use assistive aids like walkers and canes and exercise regimens. Physical therapists practice in all health care environments including the home, hospital, and rehabilitation centers. Podiatrists: Podiatrists provide care and services to patients who have foot problems. They often work with diabetic patients to clip toenails and provide foot care to prevent complications. Prosthetists: Prosthetists design, fit, and supply the patient with an artificial body part such as a leg or arm prosthesis. They adjust prosthesis to ensure proper fit, patient comfort, and functioning. Psychologists and Psychiatrists: Psychologists and psychiatrists provide mental health and psychiatric services to patients with mental health disorders and provide psychological support to family members and significant others as indicated. Respiratory Therapists: Respiratory therapists treat respiratory-related conditions in patients. Their specialized respiratory care includes managing oxygen therapy; drawing arterial blood gases; managing patients on specialized oxygenation devices such as mechanical ventilators, CPAP, and Bi-PAP machines; administering respiratory medications like inhalers and nebulizers; intubating patients; assisting with bronchoscopy and other respiratory-related diagnostic tests; performing pulmonary hygiene measures like chest physiotherapy; and serving an integral role during cardiac and respiratory arrests. Social Workers: Social workers counsel patients and provide psychological support, help set up community resources according to patients’ financial needs, and serve as part of the team that ensures continuity of care after the person is discharged. Speech Therapists: Speech therapists assess, diagnose, and treat communication and swallowing disorders. For example, speech therapists help patients with a disorder called expressive aphasia. They also assist patients with using word boards and other electronic devices to facilitate communication. They assess patients with swallowing disorders called dysphagia and treat them in collaboration with other members of the health care team including nurses, dieticians, and health care providers. Ancillary Department Members: Nurses also work with ancillary departments such as laboratory and radiology departments. Clinical laboratory departments provide a wide range of laboratory procedures that aid health care providers to diagnose, treat, and manage patients. These laboratories are staffed by medical technologists who test biological specimens collected from patients. Examples of laboratory tests performed include blood tests, blood banking, cultures, urine tests, and histopathology (changes in tissues caused by disease).This work is a derivative of StatPearls by Bayot and Naidoo and licensed under CC BY 4.0Radiology departments use imaging to assist providers in diagnosing and treating diseases seen within the body. They perform diagnostic tests such as X-rays, CTs, MRIs, nuclear medicine, PET scans, and ultrasound scans. Chain of Command Nurses rarely make patient decisions in isolation, but instead consult with other nurses and interprofessional team members. Concerns and questions about patient care are typically communicated according to that agency’s chain of command. In the military, chain of command refers to a hierarchy of reporting relationships – from the bottom to the top of an organization – regarding who must answer to whom. The chain of command not only establishes accountability, but also lays out lines of authority and decision-making power. The chain of command also applies to health care. For example, a registered nurse in a hospital may consult a “charge nurse,” who may consult the “nurse supervisor,” who may consult the “director of nursing,” who may consult the “vice president of nursing.” In a long-term care facility, a licensed practical/vocational nurse typically consults the registered nurse/charge nurse, who may consult with the director of nursing. Nursing students should always consult with their nursing instructor regarding questions or concerns about patient care before “going up the chain of command.” Nurse Specialties Registered nurses can obtain several types of certifications as a nurse specialist. Certification is the formal recognition of specialized knowledge, skills, and experience demonstrated by the achievement of standards identified by a nursing specialty. See the following box for descriptions of common nurse specialties. Common Nurse Specialties Critical Care Nurses provide care to patients with serious, complex, and acute illnesses or injuries that require very close monitoring and extensive medication protocols and therapies. Critical care nurses most often work in intensive care units of hospitals. Public Health Nurses work to promote and protect the health of populations based on knowledge from nursing, social, and public health sciences. Public Health Nurses most often work in municipal and state health departments. Home Health/Hospice Nurses provide a variety of nursing services for chronically ill patients and their caregivers in the home, including end-of-life care. Occupational/Employee Health Nurses provide health screening, wellness programs and other health teaching, minor treatments, and disease/medication management services to people in the workplace. The focus is on promotion and restoration of health, prevention of illness and injury, and protection from work-related and environmental hazards. Oncology Nurses care for patients with various types of cancer, administering chemotherapy and providing follow-up care, teaching, and monitoring. Oncology nurses work in hospitals, outpatient clinics, and patients’ homes. Perioperative/Operating Room Nurses provide preoperative and postoperative care to patients undergoing anesthesia or assist with surgical procedures by selecting and handling instruments, controlling bleeding, and suturing incisions. These nurses work in hospitals and outpatient surgical centers. Rehabilitation Nurses care for patients with temporary and permanent disabilities within inpatient and outpatient settings such as clinics and home health care. Psychiatric/Mental Health Nurses specialize in mental and behavioral health problems and provide nursing care to individuals with psychiatric disorders. Psychiatric nurses work in hospitals, outpatient clinics, and private offices. School Nurses provide health assessment, intervention, and follow-up to maintain school compliance with health care policies and ensure the health and safety of staff and students. They administer medications and refer students for additional services when hearing, vision, and other issues become inhibitors to successful learning. Other common specialty areas include a life span approach across health care settings and include maternal-child, neonatal, pediatric, and gerontological nursing.Institute of Medicine (US) Committee on the Robert Wood Johnson Foundation Initiative on the Future of Nursing at the Institute of Medicine. (2011). The future of nursing: Leading change, advancing health. National Academies Press. https://www.nap.edu/catalog/12956/the-future-of-nursing-leading-change-advancing-health Now that we have discussed various settings where nurses work and various nursing roles, let’s review levels of nursing education and the national licensure exam (NCLEX). 1.5 Nursing Education and the NCLEX Open Resources for Nursing (Open RN) Nursing Education and the NCLEX Everyone who wants to become a nurse has a story to tell about why they want to enter the nursing profession. What is your story? Perhaps it has been a lifelong dream to become a Life Flight nurse, or maybe you became interested after watching a nurse help you or a family member through the birth of a baby, heal from a challenging illness, or assist a loved one at the end of life. Whatever the reason, everyone who wants to become a nurse must do two things: graduate from a state-approved nursing program and pass the National Council Licensure Exam (known as the NCLEX). Nursing Programs There are several types of nursing programs you can attend to become a nurse. If your goal is to become a Licensed Practical Nurse (LPN), you must successfully complete a one-year nursing program, pass the NCLEX-PN exam, and apply to your state board of nursing to receive a LPN license. If you want to become a Registered Nurse, you can obtain either a two-year associate degree (ADN) or a four-year baccalaureate of science in nursing degree (BSN). Associate degree nursing graduates often enroll into a baccalaureate or higher degree program after they graduate. Many hospitals hire ADN nurses on a condition they complete their BSN within a specific time frame. A BSN is required for military nursing, case management, public health nursing, and school-based nursing services. Another lesser-known option to become an RN is to complete a three-year hospital-based diploma program, which was historically the most common way to become a nurse. Diploma programs have slowly been replaced by college degrees, and now only nine states offer this option.NCSBN. (2019). 2018 NCLEX examination statistics 77. https://www.ncsbn.org/2018_NCLEXExamStats.pdf After completing a diploma program, associate degree, or baccalaureate degree, nursing graduates must successfully pass the NCLEX-RN to apply for a registered nursing license from their state’s Board of Nursing. NCLEX Nursing graduates must successfully pass the National Council Licensure Examination (NCLEX) to receive a nursing license. Registered nurses must successfully pass the NCLEX-RN exam, and Licensed Practical Nurses (LPNs) or Licensed Vocational Nurses (LVNs) must pass the NCLEX-PN exam. The NCLEX-PN and NCLEX-RN are online, adaptive tests taken at a specialized testing center. The NCLEX tests knowledge, skills, and abilities essential to the safe and effective practice of nursing at the entry level. NCLEX exams are continually reviewed and updated based on surveys of newly graduated nurses every three years. Both the NCLEX-RN and the NCLEX-PN are variable length tests that adapt as you answer the test items. The NCLEX-RN examination can be anywhere from 75 to 265 items, depending on how quickly you are able to demonstrate your proficiency. Of these items, 15 are unscored test items. The time limit for this examination is six hours. The NCLEX-PN examination can be anywhere from 85 to 205 items. Of these items, 25 are unscored items. The time limit for this examination is five hours.NCSBN. (2019). NCLEX & Other Exams. https://www.ncsbn.org/nclex.htm In 2023, the Next Generation NCLEX (NGN) is anticipated to go into effect. Examination questions on the NGN will use the new Clinical Judgment Measurement Model as a framework to measure prelicensure nursing graduates’ clinical judgment and decision-making. The critical thinking model called the “Nursing Process” (discussed in Chapter 4 of this book) will continue to underlie the NGN, but candidates will notice new terminology used to assess their decision-making. For example, candidates may be asked to “recognize cues,” “analyze cues,” “create a hypothesis,” “prioritize hypotheses,” “generate solutions,” “take actions,” or “evaluate outcomes.”NCSBN. (2021). NCSBN Next Generation NCLEX Project. https://www.ncsbn.org/next-generation-nclex.htm For this reason, many of the case studies and learning activities included in this book will use similar terminology as the NGN. There will also be new types of examination questions on the NGN, including case studies, enhanced hot spots, drag and drop ordering of responses, multiple responses, and embedded answer choices within paragraphs of text. View sample NGN questions in the following hyperlink. NCSBN’s rationale for including these types of questions is to “measure the nursing clinical judgment and decision-making ability of prospective entry-level nurses to protect the public’s health and welfare by assuring that safe and competent nursing care is provided by licensed nurses.”NCSBN. (2021). NCSBN Next Generation NCLEX Project. https://www.ncsbn.org/next-generation-nclex.htm Similar questions have been incorporated into learning activities throughout this textbook. Use the hyperlinks below to read more information about the NCLEX and the Next Generation NCLEX. Read more information about the NCLEX & Test Plans. Review sample Next Generation NCLEX questions at https://www.ncsbn.org/NGN-Sample-Questions.pdf. Nurse Licensure Compact The Nurse Licensure Compact (NLC) allows a nurse to have one multistate nursing license with the ability to practice in their home state, as well as in other compact states. As of 2020, 33 states have implemented NLC legislation. Read additional details about the Nurse Licensure Compact. Advanced Nursing Degrees After obtaining an RN license, nurses can receive advanced degrees to expand their opportunities in the nursing profession. Master’s Degree in Nursing A Master’s of Science in Nursing Degree (MSN) requires additional credits and years of schooling beyond the BSN. There are a variety of potential focuses in this degree, including Nurse Educator and Advanced Practice Nurse (APRN). Certifications associated with an MSN degree are Certified Nurse Educator (CNE), Nurse Practitioner (NP), Clinical Nurse Specialist (CNS), Certified Registered Nurse Anesthetist (CRNA), and Certified Nurse Midwife (CNM). Certifications require the successful completion of a certification exam, as well as continuing education requirements to maintain the certification. Scope of practice for advanced practice nursing roles is defined by each state’s Nurse Practice Act. Doctoral Degrees in Nursing Doctoral nursing degrees include the Doctor of Philosophy in Nursing (PhD) and the Doctor of Nursing Practice (DNP). PhD-prepared nurses complete doctoral work that is focused on research. They often teach in a university setting or environment to conduct research. DNP-prepared nurses complete doctoral work that is focused on clinical nursing practice. They typically have work roles in advanced nursing practice, clinical leadership, or academic settings. Lifelong Learning No matter what nursing role or level of nursing education you choose, nursing practice changes rapidly and is constantly updated with new evidence-based practices. Nurses must commit to lifelong learning to continue to provide safe, quality care to their patients. Many states require continuing education credits to renew RN licenses, whereas others rely on health care organizations to set education standards and ongoing educational requirements. Now that we have discussed nursing roles and education, let’s review legal and ethical considerations in nursing. 1.6 Legal Considerations & Ethics Open Resources for Nursing (Open RN) Legal Considerations As discussed earlier in this chapter, nurses can be reprimanded or have their licenses revoked for not appropriately following the Nurse Practice Act in the state they are practicing. Nurses can also be held legally liable for negligence, malpractice, or breach of patient confidentiality when providing patient care. Negligence and Malpractice Negligence is a “general term that denotes conduct lacking in due care, carelessness, and a deviation from the standard of care that a reasonable person would use in a particular set of circumstances.”Missouri Department of Health & Senior Services. (n.d.). Negligence and malpractice. https://health.mo.gov/living/lpha/phnursing/negligence.php#:~:text=Negligence%20is%3A,a%20particular%20set%20of%20circumstances. Malpractice is a more specific term that looks at a standard of care, as well as the professional status of the caregiver.” Missouri Department of Health & Senior Services. (n.d.). Negligence and malpractice. https://health.mo.gov/living/lpha/phnursing/negligence.php#:~:text=Negligence%20is%3A,a%20particular%20set%20of%20circumstances. To prove negligence or malpractice, the following elements must be established in a court of law: - Duty owed the patient - Breach of duty owed the patient - Foreseeability - Causation - Injury - DamagesMissouri Department of Health & Senior Services. (n.d.). Negligence and malpractice. https://health.mo.gov/living/lpha/phnursing/negligence.php#:~:text=Negligence%20is%3A,a%20particular%20set%20of%20circumstances. To avoid being sued for negligence or malpractice, it is essential for nurses and nursing students to follow the scope and standards of practice care set forth by their state’s Nurse Practice Act; the American Nurses Association; and employer policies, procedures, and protocols to avoid the risk of losing their nursing license. Examples of nurses breach of duty that can be viewed as negligence include:Vera, M. (2020). Nursing care plan (NCP): Ultimate guide and database. https://nurseslabs.com/nursing-care-plans/#:~:text=Collaborative%20interventions%20are%20actions%20that,to%20gain%20their%20professional%20viewpoint. - Failure to Assess: Nurses should assess for all potential nursing problems/diagnoses, not just those directly affected by the medical disease. For example, all patients should be assessed for fall risk and appropriate fall precautions implemented. - Insufficient monitoring: Some conditions require frequent monitoring by the nurse, such as risk for falls, suicide risk, confusion, and self-injury. - Failure to Communicate: - Lack of documentation: A basic rule of thumb in a court of law is that if an assessment or action was not documented, it is considered not done. Nurses must document all assessments and interventions, in addition to the specific type of patient documentation called a nursing care plan. - Lack of provider notification: Changes in patient condition should be urgently communicated to the health care provider based on patient status. Documentation of provider notification should include the date, time, and person notified and follow-up actions taken by the nurse. - Failure to Follow Protocols: Agencies and states have rules for reporting certain behaviors or concerns. For example, a nurse is required to report suspicion of patient, child, or elder abuse based on data gathered during an assessment. Patient Confidentiality In addition to negligence and malpractice, patient confidentiality is a major legal consideration for nurses and nursing students. Patient confidentiality is the right of an individual to have personal, identifiable medical information, referred to as protected health information (PHI), kept private. This right is protected by federal regulations called the Health Insurance Portability and Accountability Act (HIPAA). HIPAA was enacted in 1996 and was prompted by the need to ensure privacy and protection of personal health records and data in an environment of electronic medical records and third-party insurance payers. There are two main sections of HIPAA law, the Privacy Rule and the Security Rule. The Privacy Rule addresses the use and disclosure of individuals’ health information. The Security Rule sets national standards for protecting the confidentiality, integrity, and availability of electronically protected health information. HIPAA regulations extend beyond medical records and apply to patient information shared with others. Therefore, all types of patient information should only be shared with health care team members who are actively providing care to them. How do HIPAA regulations affect you as a student nurse? You are required to adhere to HIPAA guidelines from the moment you begin to provide patient care. Nursing students may be disciplined or expelled by their nursing program for violating HIPAA. Nurses who violate HIPAA rules may be fired from their jobs or face lawsuits. See the following box for common types of HIPAA violations and ways to avoid them. Common HIPAA Violations and Ways to Avoid ThemPatterson, A. (2018, July 3). Most common HIPAA violations with examples. Inspired eLearning. https://inspiredelearning.com/blog/hipaa-violation-examples/ - Gossiping in the hallways or otherwise talking about patients where other people can hear you. It is understandable that you will be excited about what is happening when you begin working with patients and your desire to discuss interesting things that occur. As a student, you will be able to discuss patient care in a confidential manner behind closed doors with your instructor. However, as a health care professional, do not talk about patients in the hallways, elevator, breakroom, or with others who are not directly involved with that patient’s care because it is too easy for others to overhear what you are saying. - Mishandling medical records or leaving medical records unsecured. You can breach HIPAA rules by leaving your computer unlocked for anyone to access or by leaving written patient charts in unsecured locations. You should never share your password with anyone else. Make sure that computers are always locked with a password when you step away from them and paper charts are closed and secured in an area where unauthorized people don’t have easy access to them. NEVER take records from a facility or include a patient’s name on paperwork that leaves the facility. - Illegally or unauthorized accessing of patient files. If someone you know, like a neighbor, coworker, or family member is admitted to the unit you are working on, do not access their medical record unless you are directly caring for them. Facilities have the capability of tracing everything you access within the electronic medical record and holding you accountable. This rule holds true for employees who previously cared for a patient as a student; once your shift is over as a student, you should no longer access that patient’s medical records. - Sharing information with unauthorized people. Anytime you share medical information with anyone but the patient themselves, you must have written permission to do so. For instance, if a husband comes to you and wants to know his spouse’s lab results, you must have permission from his spouse before you can share that information with him. Just confirming or denying that a patient has been admitted to a unit or agency can be considered a breach of confidentiality. - Information can generally be shared with the parents of children until they turn 18, although there are exceptions to this rule if the minor child seeks birth control, an abortion, or becomes pregnant. After a child turns 18, information can no longer be shared with the parent unless written permission is provided, even if the minor is living at home and/or the parents are paying for their insurance or health care. As a general rule, any time you are asked for patient information, check first to see if the patient has granted permission. - Texting or e-mailing patient information on an unencrypted device. Only use properly encrypted devices that have been approved by your health care facility for e-mailing or faxing protected patient information. Also, ensure that the information is being sent to the correct person, address, or phone number. - Sharing information on social media. Never post anything on social media that has anything to do with your patients, the facility where you are working or have clinical, or even how your day went at the agency. Nurses and other professionals have been fired for violating HIPAA rules on social media.Karimi, H., & Masoudi Alavi, N. (2015). Florence Nightingale: The mother of nursing. Nursing and Midwifery Studies, 4(2), e29475. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4557413/,American Nurses Association. (n.d.). About ANA. https://www.nursingworld.org/ana/about-ana/,American Nurses Association. (n.d.). Scope of practice. https://www.nursingworld.org/practice-policy/scope-of-practice/ Social Media Guidelines Nursing students, nurses, and other health care team members must use extreme caution when posting to Facebook, Instagram, Twitter, Snapchat, and other social media sites. Information related to patients, patient care, and/or health care agencies should never be posted on social media; health care team members who violate this guideline can lose their jobs and may face legal action and students can be disciplined or expelled from their nursing program. Be aware that even if you think you are posting in a private group, the information can become public. The American Nurses Association (ANA) has established the following principles for nurses using social media:American Nurses Association. (n.d.). Social media. https://www.nursingworld.org/social/ - Nurses must not transmit or place online individually identifiable patient information. - Nurses must observe ethically prescribed professional patient-nurse boundaries. - Nurses should understand that patients, colleagues, organizations, and employers may view postings. - Nurses should take advantage of privacy settings and seek to separate personal and professional information online. - Nurses should bring content that could harm a patient’s privacy, rights, or welfare to the attention of appropriate authorities. - Nurses should participate in developing organizational policies governing online conduct. In addition to these principles, the ANA has also provided these tips for nurses and nursing students using social media:American Nurses Association. (n.d.). Social media. https://www.nursingworld.org/social/ - Remember that standards of professionalism are the same online as in any other circumstance. - Do not share or post information or photos gained through the nurse-patient relationship. - Maintain professional boundaries in the use of electronic media. Online contact with patients blurs this boundary. - Do not make disparaging remarks about patients, employers, or coworkers, even if they are not identified. - Do not take photos or videos of patients on personal devices, including cell phones. - Promptly report a breach of confidentiality or privacy. Read more about the ANA’s Social Media Principles. Code of Ethics In addition to legal considerations, there are also several ethical guidelines for nursing care. There is a difference between morality, ethical principles, and a code of ethics. Morality refers to “personal values, character, or conduct of individuals within communities and societies.”American Nurses Association. (2015). Code of ethics for nurses with interpretive statements. American Nurses Association. https://www.nursingworld.org/practice-policy/nursing-excellence/ethics/code-of-ethics-for-nurses/coe-view-only/ An ethical principle is a general guide, basic truth, or assumption that can be used with clinical judgment to determine a course of action. Four common ethical principles are beneficence (do good), nonmaleficence (do no harm), autonomy (control by the individual), and justice (fairness). A code of ethics is set for a profession and makes their primary obligations, values, and ideals explicit. The American Nursing Association (ANA) guides nursing practice with the Code of Ethics for Nurses.American Nurses Association. (2015). Code of ethics for nurses with interpretive statements. American Nurses Association. https://www.nursingworld.org/practice-policy/nursing-excellence/ethics/code-of-ethics-for-nurses/coe-view-only/ This code provides a framework for ethical nursing care and a guide for decision-making. The Code of Ethics for Nurses serves the following purposes: - It is a succinct statement of the ethical values, obligations, duties, and professional ideals of nurses individually and collectively. - It is the profession’s nonnegotiable ethical standard. - It is an expression of nursing’s own understanding of its commitment to society.American Nurses Association. (2015). Code of ethics for nurses with interpretive statements. American Nurses Association. https://www.nursingworld.org/practice-policy/nursing-excellence/ethics/code-of-ethics-for-nurses/coe-view-only/ The ANA Code of Ethics contains nine provisions. See a brief description of each provision in the following box. Provisions of the ANA Code of EthicsAmerican Nurses Association. (2015). Code of ethics for nurses with interpretive statements. American Nurses Association. https://www.nursingworld.org/practice-policy/nursing-excellence/ethics/code-of-ethics-for-nurses/coe-view-only/ The nine provisions of the ANA Code of Ethics are briefly described below. The full code is available to read for free at Nursingworld.org. Provision 1: The nurse practices with compassion and respect for the inherent dignity, worth, and unique attributes of every person. Provision 2: The nurse’s primary commitment is to the patient, whether an individual, family, group, community, or population. Provision 3: The nurse promotes, advocates for, and protects the rights, health, and safety of the patient. Provision 4: The nurse has authority, accountability, and responsibility for nursing practice; makes decisions; and takes action consistent with the obligation to promote health and to provide optimal care. Provision 5: The nurse owes the same duties to self as to others, including the responsibility to promote health and safety, preserve wholeness of character and integrity, maintain competence, and continue personal and professional growth. Provision 6: The nurse, through individual and collective effort, establishes, maintains, and improves the ethical environment of the work setting and conditions of employment that are conducive to safe, quality health care. Provision 7: The nurse, in all roles and settings, advances the profession through research and scholarly inquiry, professional standards development, and the generation of both nursing and health policy. Provision 8: The nurse collaborates with other health professionals and the public to protect human rights, promote health diplomacy, and reduce health disparities. Provision 9: The profession of nursing, collectively through its professional organizations, must articulate nursing values, maintain the integrity of the profession, and integrate principles of social justice into nursing and health policy. The ANA Center for Ethics and Human Rights In addition to publishing the Code of Ethics, the ANA Center for Ethics and Human Rights was established to help nurses navigate ethical and value conflicts and life-and-death decisions, many of which are common to everyday practice. Check your knowledge with the following questions: An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=709#h5p-57 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=709#h5p-58 1.7 Professional Organizations Open Resources for Nursing (Open RN) Professional Nursing Organizations In addition to the ANA’s Nursing: Scope and Standards of Practice and Code of Ethics for Nurses, there are several professional nursing organizations that provide specialized standards for nursing care and promote continuous quality improvement. The following box contains examples of many organizations that significantly guide the overall nursing profession. Examples of Professional Nursing Organizations American Nursing Association As described previously in this chapter, the American Nurses Association (ANA) guides professional nursing practice with publications, in addition to establishing the ANA Scope and Standards of Practice and ANA Code of Ethics. The ANA also publishes a monthly journal on nursing topics for its members called The American Nurse. Read more information about the ANA. American Nurses Credentialing Center The American Nurses Credentialing Center (ANCC) credentials both organizations and individuals. ANCC certification provides individual nurses certification in specialized nursing knowledge. The ANCC accreditation program recognizes the importance of high-quality continuing nursing education, interprofessional continuing education, transition to practice programs, and skills-based competency programs. Around the world, ANCC-accredited organizations provide nurses with the knowledge and skills to help improve care and patient outcomes. Read more about the American Nurses Credentialing Center National League for Nursing The focus of the National League for Nursing (NLN) is to promote excellence in nursing education. The NLN establishes standards and evaluates nursing education programs, promotes faculty development, funds nursing education research, and publishes the research journal Nursing Education Perspectives.Wisconsin Administrative Code. (2018). Chapter N 6 standards of practice for registered nurses and licensed practical nurses. https://docs.legis.wisconsin.gov/code/admin_code/n/6.pdf Read more about the National League for Nursing. Accreditation Commission for Education in Nursing The Accreditation Commission for Education in Nursing (ACEN) is one of the organizations that provide accreditation for nursing education to recognize educational institutions or programs that have been found to meet or exceed standards and criteria for educational quality. ACEN provides accreditation for each of the 16 technical colleges in the Wisconsin Technical College System. As a nursing student, you may be asked to provide vital feedback to ACEN site visitors on your nursing program. Read more about ACEN accreditation. Commission on Collegiate Nursing Education The Commission on Collegiate Nursing Education (CCNE) ensures the quality and integrity of baccalaureate, graduate, and residency programs in nursing. Read more about CCNE accreditation. National Student Nurses’ Association The mission of the National Student Nurses’ Association (NSNA) is to “mentor students preparing for initial licensure as registered nurses, and to convey the standards, ethics, and skills that students will need as responsible and accountable leaders and members of the profession.”National Student Nurses’ Association. (n.d.). About us. https://www.nsna.org/about-nsna.html NSNA holds national conventions and publishes the journal Imprint. Read more about the National Student Nurses’ Association. Specialty Nursing Organizations There are many specialty organizations that provide certification, publish scope of practice documents for that specialty, and issue position statements.American Nurses Association. (n.d.). Academy of Medical-Surgical Nurses Wound, Ostomy and Continence Nursing Association of Women’s Health, Obstetric, and Neonatal Nurses View the AMSN YouTube videoAMSN 6). MSNCB. (2020, May 6). AMSN…The Present. [Video]. YouTube. All rights reserved. https://youtu.be/unRSCXdhCgk from the former president of the Academy of Medical-Surgical Nurses about important nursing issues. 1.8 Quality and Evidence-Based Practice Open Resources for Nursing (Open RN) The American Nursing Association (ANA), various professional nursing organizations, and federal agencies continually work to improve the quality of patient care. Nurses must also be individually dedicated to providing quality patient care based on current evidence-based practices. Quality of Practice One of the American Nurses Association (ANA) Standards of Professional Practice is “Quality of Practice.” This standard emphasizes that “nursing practice is safe, effective, efficient, equitable, timely, and person-centered.”American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association Quality is defined as, “The degree to which nursing services for healthcare consumers, families, groups, communities, and populations increase the likelihood of desirable outcomes and are consistent with evolving nursing knowledge.”American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association Every nurse is responsible for providing quality care to their patients by following the standards set forth by various organizations, as well as personally incorporating evidence-based practice. Quality is everyone’s responsibility and it takes the entire health care team to ensure that quality care is provided to each and every patient. For example, turning an immobile patient every two hours to prevent pressure injuries requires the dedication of many staff members throughout the day and night. Quality actions can also be formalized on a specific unit, such as the review of data related to patient falls with specific unit-based interventions formally put into place. This commitment to quality practice requires lifelong learning after you have completed your formal nursing education to remain current with new evidence-based practices. Learning how to provide safe, quality nursing practice begins in nursing school. The Quality and Safety Education for Nurses (QSEN) project encourages future nurses to continuously improve the quality and safety of the health care systems in which they work. The vision of the QSEN project is to “inspire health care professionals to put quality and safety as core values to guide their work.”QSEN Institute. (n.d.). Project overview. http://qsen.org/about-qsen/project-overview/ Nurses and nursing students are expected to participate in quality improvement (QI) initiatives by identifying gaps where change is needed and implementing initiatives to resolve these gaps. Quality improvement is defined as the combined and unceasing efforts of everyone – health care professionals, patients and their families, researchers, payers, planners, and educators – to make the changes that will lead to optimal patient outcomes (health), improved system performance (care), and enhanced professional development (learning).Batalden, P. B., & Davidoff, F. (2007). What is “quality improvement” and how can it transform healthcare? BMJ Quality & Safety, 16(1), 2–3. https://doi.org/10.1136/qshc.2006.022046 As a nursing student, you can immediately begin to contribute to improving the quality of nursing practice by participating in quality improvement initiatives. Read more about the QSEN project. Evidence-Based Practice in Nursing Evidence-based practice is a component of ANA’s “Scholarly Inquiry” Standard of Professional Practice. Evidence-based practice is defined as, “A lifelong problem-solving approach that integrates the best evidence from well-designed research studies and evidence-based theories; clinical expertise and evidence from assessment of the healthcare consumer’s history and condition, as well as health care resources; and patient, family, group, community, and population preferences and values.”American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. Utilizing evidence-based practice means that nurses and nursing students provide patient care based on research studies and clinical expertise and do not just do something “because that’s the way we’ve always done it.” A simple example of nurses promoting evidence-based practice to help patients is using peppermint to relieve nausea. Throughout history, peppermint was used for an upset stomach and to relieve the feeling of nausea. This idea was frequently rejected in the medical field because there was no scientific evidence to support it. However, In 2016, Lynn Bayne and Helen Hawrylack, two nurse researchers, developed a peppermint inhaler for patients to use when they were feeling nauseated and found it was 93% effective in relieving nausea.ChristianaCare News. (2016, May 16). Nurse researchers develop peppermint inhaler to relieve post-op nausea. https://news.christianacare.org/2016/05/nurse-researchers-develop-peppermint-inhaler-to-relieve-post-op-nausea/ Nursing students should implement evidence-based practice as they begin their nursing career by ensuring the resources they use to prepare for patient care are valid and credible. For this reason, hyperlinks to credible and reliable sources are provided throughout this textbook. 1.9 Learning Activities Open Resources for Nursing (Open RN) Learning Activities (Answers to “Learning Activities” can be found in the “Answer Key” at the end of the book. Answers to interactive activity elements will be provided within the element as immediate feedback.) Apply what you have learned from this chapter by completing the following learning activities: 1. You have been assisting a critical care nurse with the care of a patient who has been experiencing significantly low blood pressures throughout the day. The nurse has to step away from the bedside to take a phone call and instructs you to increase the intravenous (IV) medication if the patient’s systolic blood pressure drops below 90 mmHg. What is the appropriate response to this instruction? 2. You are completing a clinical rotation on a medical surgical unit and are invited to join a few staff nurses in the breakroom for a lunch break. While you are in the breakroom, you notice one of the staff nurses complaining loudly about a patient and discussing sensitive patient care information. What is an appropriate response to this situation? An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=102#h5p-88 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=102#h5p-2 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=102#h5p-3 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=102#h5p-56 I. Glossary Open Resources for Nursing (Open RN) Advanced Practice Nurse (APRN): An RN who has a graduate degree and advanced knowledge. There are four categories of APRNs: certified nurse-midwife (CNM), clinical nurse specialist (CNS), certified nurse practitioner (CNP), or certified registered nurse anesthetist (CRNA). These nurses can diagnose illnesses and prescribe treatments and medications.NCSBN. https://www.ncsbn.org/index.htm ANA Standards of Professional Nursing Practice: Authoritative statements of the duties that all registered nurses, regardless of role, population, or specialty, are expected to perform competently. The Standards of Professional Nursing Practice describe a competent level of nursing practice as demonstrated by the critical thinking model known as the nursing process. The nursing process includes the components of assessment, diagnosis, outcomes identification, planning, implementation, and evaluation.American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. ANA Standards of Professional Performance: Standards that describe a competent level of behavior in the professional role of the nurse, including activities related to ethics, advocacy, respectful and equitable practice, communication, collaboration, leadership, education, scholarly inquiry, quality of practice, professional practice evaluation, resource stewardship, and environmental health.American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. Basic nursing care: Care that can be performed following a defined nursing procedure with minimal modification in which the responses of the patient to the nursing care are predictable.Wisconsin Administrative Code. (2018). Chapter N 6 standards of practice for registered nurses and licensed practical nurses. https://docs.legis.wisconsin.gov/code/admin_code/n/6.pdf Board of Nursing: The state-specific licensing and regulatory body that sets the standards for safe nursing care, decides the scope of practice for nurses within its jurisdiction, and issues licenses to qualified candidates. Chain of command: A hierarchy of reporting relationships in an agency that establishes accountability and lays out lines of authority and decision-making power. Code of ethics: A code that applies normative, moral guidance for nurses in terms of what they ought to do, be, and seek. A code of ethics makes the primary obligations, values, and ideals of a profession explicit. Dysphagia: Impaired swallowing. Ethical principle: An ethical principle is a general guide, basic truth, or assumption that can be used with clinical judgment to determine a course of action. Four common ethical principles are beneficence (do good), nonmaleficence (do no harm), autonomy (control by the individual), and justice (fairness). Evidence-based practice: A lifelong problem-solving approach that integrates the best evidence from well-designed research studies and evidence-based theories; clinical expertise and evidence from assessment of the health consumer’s history and condition, as well as health care resources; and patient, family, group, community, and population preferences and values.American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. Expressive aphasia: The impaired ability to form words and speak. Licensed Practical Nurse/Vocational Nurse (LPN/LVN): An individual who has completed a state-approved practical or vocational nursing program, passed the NCLEX-PN examination, and is licensed by their state Board of Nursing to provide patient care.NCSBN. https://www.ncsbn.org/index.htm Malpractice: A specific term that looks at a standard of care, as well as the professional status of the caregiver.Missouri Department of Health & Senior Services. (n.d.). Negligence and malpractice. https://health.mo.gov/living/lpha/phnursing/negligence.php#:~:text=Negligence%20is%3A,a%20particular%20set%20of%20circumstances. Morality: Personal values, character, or conduct of individuals within communities and societies.American Nurses Association. (2015). Code of ethics for nurses with interpretive statements. American Nurses Association. https://www.nursingworld.org/practice-policy/nursing-excellence/ethics/code-of-ethics-for-nurses/coe-view-only/ Negligence: A “general term that denotes conduct lacking in due care, carelessness, and a deviation from the standard of care that a reasonable person would use in a particular set of circumstances.”Missouri Department of Health & Senior Services. (n.d.). Negligence and malpractice. https://health.mo.gov/living/lpha/phnursing/negligence.php#:~:text=Negligence%20is%3A,a%20particular%20set%20of%20circumstances. Nurse Licensure Compact (NLC): Allows a nurse to have one multistate license with the ability to practice in the home state and other compact states. Nursing: Nursing integrates the art and science of caring and focused on the protection, promotion, and optimization of health and human functioning; prevention of illness and injury; facilitation of healing; and alleviation of suffering through compassionate presence. Nursing is the diagnosis and treatment of human responses and advocacy in the care of individuals, families, groups, communities, and populations in recognition of the connection of all humanity.American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. Nurse Practice Act (NPA): Legislation enacted by each state that establishes regulations for nursing practice within that state by defining the requirements for licensure, as well as the scope of nursing practice. Patient confidentiality: Keeping your patient’s Protected Health Information (PHI) protected and known only by those health care team members directly providing care for the patient. Primary care: Care that is provided to patients to promote wellness and prevent disease from occurring. This includes health promotion, education, protection (such as immunizations), early disease screening, and environmental considerations. Protocol: A precise and detailed written plan for a regimen of therapy.Wisconsin Administrative Code. (2018). Chapter N 6 standards of practice for registered nurses and licensed practical nurses. https://docs.legis.wisconsin.gov/code/admin_code/n/6.pdf Provider: A physician, podiatrist, dentist, optometrist, or advanced practice nurse provider.Wisconsin Administrative Code. (2018). Chapter N 6 standards of practice for registered nurses and licensed practical nurses. https://docs.legis.wisconsin.gov/code/admin_code/n/6.pdf Quality: The degree to which nursing services for health care consumers, families, groups, communities, and populations increase the likelihood of desirable outcomes and are consistent with evolving nursing knowledge.”American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. Registered Nurse (RN): An individual who has graduated from a state-approved school of nursing, passed the NCLEX-RN examination, and is licensed by a state board of nursing to provide patient care.NCSBN. https://www.ncsbn.org/index.htm Safety culture: A culture established within health care agencies that empowers nurses, nursing students, and other staff members to speak up about risks to patients and to report errors and near misses, all of which drive improvement in patient care and reduce the incident of patient harm. Scope of practice: Services that a qualified health professional is deemed competent to perform and permitted to undertake – in keeping with the terms of their professional license. Secondary care: Care that occurs when a person has contracted an illness or injury and is in need of medical care. Tertiary care: A type of care that deals with the long-term effects from chronic illness or condition, with the purpose to restore physical and mental function that may have been lost. The goal is to achieve the highest level of functioning possible with this chronic illness. Unlicensed Assistive Personnel: Any unlicensed person, regardless of title, who performs tasks delegated by a nurse. This includes certified nursing aides/assistants (CNAs), patient care assistants (PCAs), patient care technicians (PCTs), state tested nursing assistants (STNAs), nursing assistants-registered (NA/Rs) or certified medication aides/assistants (MA-Cs). Certification of UAPs varies between jurisdictions.NCSBN. https://www.ncsbn.org/index.htm Communication II 2.1 Communication Introduction Open Resources for Nursing (Open RN) Learning Objectives - Assess one’s own communication skills and effectivenessAmerican Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association - Demonstrate cultural humility, professionalism, and respect when communicatingAmerican Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association - Use communication styles and methods that demonstrate caring, respect, active listening, authenticity, and trustAmerican Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association - Maintain communication with interprofessional team members and others to facilitate safe transitions and continuity in care deliveryAmerican Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association - Use therapeutic communication techniques - Confirm the recipient of the communication heard and understands the messageAmerican Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association - Apply principles of distance and space - Discuss strategies for maintaining confidentiality - Use technology to access current and reliable information - Use correct medical terminology and abbreviations - Report significant patient information verbally and in writing - Document according to legal guidelines Strong communication skills are essential to provide safe, quality, patient-centered care. Nurses develop therapeutic relationships with patients and family members each day to ensure that health care concerns and needs are addressed. If communication breaks down, information exchange stops and needs go unidentified. Nurses optimize communication channels with patients and families by establishing trust and actively listening to health care concerns. Additionally, the nurse is vital for ensuring that information transfer occurs within the multidisciplinary team. Communication with other health care team members is professional, organized, accurate, complete, and concise. This chapter will review methods for establishing good communication. Before getting started, view the following video and reflect on the often invisible needs of those around us and the difference we can make by creating caring human connections. View the video: Empathy: The Human Connection to Patient Care.Cleveland Clinic. (2013, February 27). Empathy: The human connection to patient care. [Video]. YouTube. All rights reserved. https://youtu.be/cDDWvj_q-o8 2.2 Basic Communication Concepts Open Resources for Nursing (Open RN) Effective communication is one of the Standards of Professional Performance established by the American Nurses Association. The standard states, “The registered nurse communicates effectively in all areas of practice.”American Nurses Association. (2015). Nursing: Scope and standards of practice (3rd ed.). American Nurses Association. There are several concepts related to effective communication such as demonstrating appropriate verbal and nonverbal communication, using assertive communication, being aware of personal space, and overcoming common barriers to effective communication. Types of Communication Verbal Communication Effective communication requires each interaction to include a sender of the message, a clear and concise message, and a receiver who can decode and interpret that message. The receiver also provides a feedback message back to the sender in response to the received message. See Figure 2.1“Osgood-Schramm-model-of-communication.jpg“ by Jordan Smith at eCampus Ontario is licensed under CC BY 4.0. Access for free at https://ecampusontario.pressbooks.pub/communicationatwork/chapter/1-3-the-communication-process/ for an image of effective communication between a sender and receiver. Nurses assist patients and their family members to understand health care needs and treatments by using verbal, nonverbal, and written communication. Verbal communication is more than just talking. Effective verbal communication is defined as an exchange of information using words understood by the receiver in a way that conveys professional caring and respect.This work is a derivative of Human Relations by LibreTexts and is licensed under CC BY-NC-SA 4.0 Nurses who speak using extensive medical jargon or slang may create an unintended barrier to their own verbal communication processes. When communicating with others, it is important for the nurse to assess the receiver’s preferred method of communication and individual receiver characteristics that might influence communication, and subsequently adapt communication to meet the receiver’s needs. For example, the nurse may adapt postsurgical verbal instruction for a pediatric versus an adult patient. Although the information requirements regarding signs of infection, pain management, etc., might be similar, the way in which information is provided may be quite different based on developmental level. Regardless of the individual adaptations that are made, the nurse must be sure to always verify patient understanding. Nonverbal Communication In addition to communicating verbally, the nurse must also be aware of messages sent by nonverbal communication. Nonverbal communication can have a tremendous impact on the communication experience and may be much more powerful than the verbal message itself. You may have previously learned that 80% of communication is nonverbal communication (see Figure 2.2“Constituents of Communication.png” by jb11ko, lb13an, ad14xz, jb12xu is licensed under CC BY-SA 4.0). The importance of nonverbal communication during communication has also been described in percentages of 55, 38, and 7, meaning 55% of communication is body language, 38% is tone of voice, and 7% is the actual words spoken.Thompson, J. (2011). Is nonverbal communication a numbers game? Psychology Today. https://www.psychologytoday.com/us/blog/beyond-words/201109/is-nonverbal-communication-numbers-game Nonverbal communication includes body language and facial expressions, tone of voice, and pace of the conversation. For example, compare the nonverbal communication messages in Figures 2.3“I’m angry” by WiLPrZ is licensed under CC BY-NC-ND 2.0 and 2.4.“Happy Toddler” by Chris Bloom is licensed under CC BY-SA 2.0 What nonverbal cues do you notice about both toddlers? Nurses should be attentive to their nonverbal communication cues and the messages they provide to patients and their families. Nurses should be purposeful in their use of nonverbal communication that conveys a feeling of caring.This work is a derivative of Human Relations by LibreTexts and is licensed under CC BY-NC-SA 4.0 What nonverbal cues do you notice about the nurse in Figure 2.5“PIXNIO-42752-4542×3003.jpg” by James Gathany, Judy Schmidt, USCDCP is in the Public Domain that provide a perception of professional caring? Nurses use nonverbal communication such as directly facing patients at eye level, leaning slightly forward, and making eye contact to communicate they care about what the person is telling them and they have their full attention.Stickley, T. (2011). From SOLER to SURETY for effective non-verbal communication. Nurse Education in Practice, 11(6), 395-398. https://doi.org/10.1016/j.nepr.2011.03.021 It is common for health care team members in an acute care setting to enter a patient’s room and begin interacting with a patient who is seated or lying in bed. However, it is important to remember that initial or sensitive communication exchanges are best received by the patient if the nurse and patient are at eye level. Bringing a chair to the patient’s bedside can help to facilitate engagement in the communication exchange. SOLER is common mnemonic used to facilitate nonverbal communication (sit with open posture and lean in with good eye contact in a relaxed manner). Communication Styles In addition to verbal and nonverbal communication, people communicate with others using three styles. A passive communicator puts the rights of others before their own. Passive communicators tend to be apologetic or sound tentative when they speak and often do not speak up if they feel as if they are being wronged. Aggressive communicators, on the other hand, come across as advocating for their own rights despite possibly violating the rights of others. They tend to communicate in a way that tells others their feelings don’t matter. However, assertive communicators respect the rights of others while also standing up for their own ideas and rights when communicating. An assertive person is direct, but not insulting or offensive.This work is a derivative of Human Relations by LibreTexts and is licensed under CC BY-NC-SA 4.0 Assertive communication refers to a way of conveying information that describes the facts and the sender’s feelings without disrespecting the receiver’s feelings. Using “I” messages such as, “I feel…,” “I understand…,” or “Help me to understand…” are strategies for assertive communication. This method of communicating is different from aggressive communication that uses “you” messages and can feel as if the sender is verbally attacking the receiver rather than dealing with the issue at hand. For example, instead of saying to a coworker, “Why is it always so messy in your patients’ rooms? I dread following you on the next shift!,” an assertive communicator would use “I” messages to say, “I feel frustrated spending the first part of my shift decluttering our patients’ rooms. Help me understand why it is a challenge to keep things organized during your shift?” Using assertive communication is an effective way to solve problems with patients, coworkers, and health care team members. View this humorous video demonstrating assertive communication techniques being used by the actors on a TV show: Everybody Loves Raymond Uses Active Listening – from Parent Effectiveness Training. Personal Space While being aware of verbal and nonverbal messages and communicating assertively, it is also important to be aware of others’ personal space. Proxemics is the study of personal space and provides guidelines for professional communication. The public zone is over 10 feet of distance between people and generally avoids physical contact. The social zone is four to 10 feet of distance between people. It is used during social interactions and business settings. The personal zone is 18 inches to four feet of space and is generally reserved for friends and family. Less than 18 inches is reserved for close relationships but may be invaded when in crowds or playing sports.Psychology Today. (n.d.) Proxemics. https://www.psychologytoday.com/us/basics/proxemics Nurses usually communicate within the social zone to maintain professional boundaries. However, when assessing patients and performing procedures, nurses often move into a patient’s personal zone. Nurses must be aware of patients’ feelings of psychological discomfort that can occur when invading this zone. Additionally, cultural considerations may impact the appropriateness of personal space when providing patient care. See Figure 2.6 for example of personal space zones.“Personal Space.svg” by WebHamster is licensed under CC BY-SA 3.0 Overcoming Common Barriers to Communication It is important for you to reflect on personal factors that influence your ability to communicate effectively. There are many factors that can cause the message you are trying to communicate to become distorted and not perceived by the receiver in the way you intended. It is important to seek feedback that your message is clearly understood. Nurses must be aware of these potential barriers and try to reduce their impact by continually seeking feedback and checking understanding.SkillsYouNeed. (n.d.). Barriers to effective communication. https://www.skillsyouneed.com/ips/barriers-communication.html Common barriers to communication in health care and strategies to overcome them are described in the following box.SkillsYouNeed. (n.d.). Barriers to effective communication. https://www.skillsyouneed.com/ips/barriers-communication.html Common Barriers to Communication in Health Care - Jargon: Avoid using medical terminology, complicated, or unfamiliar words. When communicating with patients, explain information in plain language that is easy to understand by those without a medical or nursing background. - Lack of attention: Nurses are typically very busy with several tasks to complete for multiple patients. It is easy to become focused on the tasks instead of the patient. When entering a patient’s room, it is helpful to pause, take a deep breath, and mindfully focus on the patient in front of you to give them your full attention. Patients should feel as if they are the center of your attention when you are with them, no matter how many other things you have going on. - Noise and other distractions: Health care environments can be very noisy with people talking in the room or hallway, the TV blaring, alarms beeping, and pages occurring overhead. Create a calm, quiet environment when communicating with patients by closing doors to the hallway, reducing the volume of the TV, or moving to a quieter area, if possible. - Light: A room that is too dark or too light can create communication barriers. Ensure the lighting is appropriate according to the patient’s preference. - Hearing and speech problems: If your patient has hearing or speech problems, implement strategies to enhance communication. See the “Adapting Your Communication” section below for strategies to address hearing and speech problems. - Language differences: If English is not your patient’s primary language, it is important to seek a medical interpreter and to also provide written handouts in the patient’s preferred language when possible. Most agencies have access to an interpreter service available by phone if they are not available on-site. - Differences in cultural beliefs: The norms of social interaction vary greatly in different cultures, as well as the ways that emotions are expressed. For example, the concept of personal space varies among cultures, and some patients are stoic about pain whereas others are more verbally expressive. Read more about caring for diverse patients in the “Diversity” chapter. - Psychological barriers: Psychological states of the sender and the receiver affect how the message is sent, received, and perceived. For example, if nurses are feeling stressed and overwhelmed with required tasks, the nonverbal communication associated with their messages such as lack of eye contact, a hurried pace, or a short tone can affect how the patient perceives the message. If a patient is feeling stressed, they may not be able to “hear” the message or they may perceive it differently than it was intended. It is important to be aware of signs of the stress response in ourselves and our patients and implement appropriate strategies to manage the stress response. See the box below for more information about strategies to manage the stress response. - Physiological barriers: It is important to be aware of patients’ potential physiological barriers when communicating. For example, if a patient is in pain, they are less likely to hear and remember what was said, so pain relief should be provided as needed before providing patient education. However, it is also important to remember that sedatives and certain types of pain medications often impair the patient’s ability to receive and perceive messages so health care documents cannot be signed by a patient after receiving these types of medications. - Physical barriers for nonverbal communication: Providing information via e-mail or text is often less effective than face-to-face communication. The inability to view the nonverbal communication associated with a message such as tone of voice, facial expressions, and general body language often causes misinterpretation of the message by the receiver. When possible, it is best to deliver important information to others using face-to-face communication so that nonverbal communication is included with the message. - Differences in perception and viewpoints: Everyone has their own beliefs and perspectives and wants to feel “heard.” When patients feel their beliefs or perspectives are not valued, they often become disengaged from the conversation or the plan of care. Nurses should provide health care information in a nonjudgmental manner, even if the patient’s perspectives, viewpoints, and beliefs are different from their own. Managing the Stress ResponseAmerican Psychological Association. (2019). Healthy Ways to Handle Life’s Stressors. https://www.apa.org/topics/stress/tips The stress response is a common psychological barrier to effective communication. It can affect the message sent by the sender or how it is received by the receiver. The stress response is a common reaction to life events, such as a nurse feeling stressed by being overwhelmed with tasks to complete for multiple patients, or a patient feeling stressed when admitted to a hospital or receiving a new diagnosis. Symptoms of the stress response include irritability, sweaty palms, a racing heart, difficulty concentrating, and impaired sleep. It is important to recognize symptoms of the stress response in ourselves and our patients and use strategies to manage the stress response when communicating. Strategies to manage the stress response are as follows: - Use relaxation breathing. Become aware of your breathing. Repeat this process at least three times in succession and then as often as needed throughout the day. - Make healthy diet choices. Avoid caffeine, nicotine, and junk food because these items can increase feelings of anxiety or being on edge. - Make time for exercise. Exercise stimulates the release of natural endorphins that reduce the body’s stress response and also helps to improve sleep. - Get enough sleep. Set aside at least 30 minutes before going to bed to wind down from the busyness of the day. Avoid using electronic devices like cell phones before bedtime because the backlight can affect sleep. - Use progressive relaxation. There are several types of relaxation techniques that focus on reducing muscle tension and using mental imagery to induce calmness. Progressive relaxation generally includes the following steps: - Start by lying down somewhere comfortable and firm, like a rug or mat on the floor. Get yourself comfortable. - Relax and try to let your mind go blank. Breathe slowly, deeply, and comfortably, while gradually and consciously relaxing all your muscles, one by one. - Work around the body one main muscle area at a time, breathing deeply, calmly, and evenly. For each muscle group, clench the muscles tightly and hold for a few seconds, and then relax them completely. Repeat the process, noticing how it feels. Do this for each of your feet, calves, thighs, buttocks, stomach, arms, hands, shoulders, and face. 2.3 Communicating with Patients Open Resources for Nursing (Open RN) Therapeutic communication is a type of professional communication used by nurses with patients and defined as, “The purposeful, interpersonal information-transmitting process through words and behaviors based on both parties’ knowledge, attitudes, and skills, which leads to patient understanding and participation.”Abdolrahimi, M., Ghiyasvandian, S., Zakerimoghadam, M., & Ebadi, A. (2017). Therapeutic communication in nursing students: A Walker & Avant concept analysis. Electronic Physician, 9(8), 4968–4977. https://doi.org/10.19082/4968 Therapeutic communication techniques used by nurses have roots going back to Florence Nightingale, who insisted on the importance of building trusting relationships with patients and believed in the therapeutic healing that resulted from nurses’ presence with patients.Karimi, H., & Masoudi Alavi, N. (2015). Florence Nightingale: The mother of nursing. Nursing and Midwifery Studies, 4(2), e29475. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4557413/. Since then, several professional nursing associations have highlighted therapeutic communication as one of the most vital elements in nursing. Read an example of a nursing student effectively using therapeutic communication with patients in the following box. An Example of Nursing Student Using Therapeutic Communication Ms. Z. is a nursing student who enjoys interacting with patients. When she goes to patients’ rooms, she greets them and introduces herself and her role in a calm tone. She kindly asks patients about their problems and notices their reactions. She does her best to solve their problems and answer their questions. Patients perceive that she wants to help them. She treats patients professionally by respecting boundaries and listening to them in a nonjudgmental manner. She addresses communication barriers and respects patients’ cultural beliefs. She notices patients’ health literacy and ensures they understand her messages and patient education. As a result, patients trust her and feel as if she cares about them, so they feel comfortable sharing their health care needs with her.Abdolrahimi, M., Ghiyasvandian, S., Zakerimoghadam, M., & Ebadi, A. (2017). Therapeutic communication in nursing students: A Walker & Avant concept analysis. Electronic Physician, 9(8), 4968–4977. https://doi.org/10.19082/4968,“beautiful african nurse taking care of senior patient in wheelchair” by agilemktg1 is in the Public Domain Active Listening and Attending Behaviors Listening is obviously an important part of communication. There are three main types of listening: competitive, passive, and active. Competitive listening happens when we are focused on sharing our own point of view instead of listening to someone else. Passive listening occurs when we are not interested in listening to the other person and we assume we understand what the person is communicating correctly without verifying. During active listening, we are communicating verbally and nonverbally that we are interested in what the other person is saying while also actively verifying our understanding with the speaker. For example, an active listening technique is to restate what the person said and then verify our understanding is correct. This feedback process is the main difference between passive listening and active listening.This work is a derivative of Human Relations by LibreTexts and is licensed under CC BY-NC-SA 4.0 Touch Touch is a powerful way to professionally communicate caring and empathy if done respectfully while being aware of the patient’s cultural beliefs. Nurses commonly use professional touch when assessing, expressing concern, or comforting patients. For example, simply holding a patient’s hand during a painful procedure can be very effective in providing comfort. See Figure 2.7Flickr – Official U.S. Navy Imagery – A nurse examines a newborn baby..jpg” by MC2 John O’Neill Herrera/U.S. Navy is in the Public Domain for an image of a nurse using touch as a therapeutic technique when caring for a patient. Therapeutic Techniques Therapeutic communication techniques are specific methods used to provide patients with support and information while focusing on their concerns. Nurses assist patients to set goals and select strategies for their plan of care based on their needs, values, skills, and abilities. It is important to recognize the autonomy of the patient to make their own decisions, maintain a nonjudgmental attitude, and avoid interrupting. Depending on the developmental stage and educational needs of the patient, appropriate terminology should be used to promote patient understanding and rapport. When using therapeutic communication, nurses often ask open-ended statements and questions, repeat information, or use silence to prompt patients to work through problems on their own.American Nurse. (n.d.). Therapeutic communication techniques. https://www.myamericannurse.com/therapeutic-communication-techniques/ Table 2.3a describes a variety of therapeutic communication techniques.American Nurse. (n.d.). Therapeutic communication techniques. https://www.myamericannurse.com/therapeutic-communication-techniques/ Table 2.3a Therapeutic Communication Techniques \| Therapeutic Technique \| Description \| \|---\|---\| \| Active Listening \| By using nonverbal and verbal cues such as nodding and saying “I see,” nurses can encourage patients to continue talking. Active listening involves showing interest in what patients have to say, acknowledging that you’re listening and understanding, and engaging with them throughout the conversation. Nurses can offer general leads such as “What happened next?” to guide the conversation or propel it forward. \| \| Using Silence \| At times, it’s useful to not speak at all. Deliberate silence can give both nurses and patients an opportunity to think through and process what comes next in the conversation. It may give patients the time and space they need to broach a new topic. \| \| Accepting \| Sometimes it is important to acknowledge a patient’s message and affirm that they’ve been heard. Acceptance isn’t necessarily the same thing as agreement; it can be enough to simply make eye contact and say, “Yes, I hear what you are saying.” Patients who feel their nurses are listening to them and taking them seriously are more likely to be receptive to care. \| \| Giving Recognition \| Recognition acknowledges a patient’s behavior and highlights it. For example, saying something such as “I noticed you took all of your medications today” draws attention to the action and encourages it. \| \| Offering Self \| Hospital stays can be lonely and stressful at times. When nurses are present with their patients, it shows patients they value them and are willing to give them time and attention. Offering to simply sit with patients for a few minutes is a powerful way to create a caring connection. \| \| Giving Broad Openings/Open-Ended Questions \| Therapeutic communication is often most effective when patients direct the flow of conversation and decide what to talk about. To that end, giving patients a broad opening such as “What’s on your mind today?” or “What would you like to talk about?” can be a good way to allow patients an opportunity to discuss what’s on their mind. \| \| Seeking Clarification \| Similar to active listening, asking patients for clarification when they say something confusing or ambiguous is important. Saying something such as “I’m not sure I understand. Can you explain it to me?” helps nurses ensure they understand what’s actually being said and can help patients process their ideas more thoroughly. \| \| Placing the Event in Time or Sequence \| Asking questions about when certain events occurred in relation to other events can help patients (and nurses) get a clearer sense of the whole picture. It forces patients to think about the sequence of events and may prompt them to remember something they otherwise wouldn’t. \| \| Making Observations \| Observations about the appearance, demeanor, or behavior of patients can help draw attention to areas that may indicate a problem. Observing that they look tired may prompt patients to explain why they haven’t been getting much sleep lately, or making an observation that they haven’t been eating much may lead to the discovery of a new symptom. \| \| Encouraging Descriptions of Perception \| For patients experiencing sensory issues or hallucinations, it can be helpful to ask about these perceptions in an encouraging, nonjudgmental way. Phrases such as “What do you hear now?” or “What does that look like to you?” give patients a prompt to explain what they’re perceiving without casting their perceptions in a negative light. \| \| Encouraging Comparisons \| Patients often draw upon previous experiences to deal with current problems. By encouraging them to make comparisons to situations they have coped with before, nurses can help patients discover solutions to their problems. \| \| Summarizing \| It is often useful to summarize what patients have said. This demonstrates to patients that the nurse was listening and allows the nurse to verify information. Ending a summary with a phrase such as “Does that sound correct?” gives patients explicit permission to make corrections if they’re necessary. \| \| Reflecting \| Patients often ask nurses for advice about what they should do about particular problems. Nurses can ask patients what they think they should do, which encourages them to be accountable for their own actions and helps them come up with solutions themselves. \| \| Focusing \| Sometimes during a conversation, patients mention something particularly important. When this happens, nurses can focus on their statement, prompting patients to discuss it further. Patients don’t always have an objective perspective on what is relevant to their case, but as impartial observers, nurses can more easily pick out the topics on which to focus. \| \| Confronting \| Nurses should only apply this technique after they have established trust. In some situations, it can be vital to the care of patients to disagree with them, present them with reality, or challenge their assumptions. Confrontation, when used correctly, can help patients break destructive routines or understand the state of their current situation. \| \| Voicing Doubt \| Voicing doubt can be a gentler way to call attention to incorrect or delusional ideas and perceptions of patients. By expressing doubt, nurses can force patients to examine their assumptions. \| \| Offering Hope and Humor \| Because hospitals can be stressful places for patients, sharing hope that they can persevere through their current situation and lightening the mood with humor can help nurses establish rapport quickly. This technique can keep patients in a more positive state of mind. However, it is important to tailor humor to the patient’s sense of humor. \| In addition to the therapeutic techniques listed in Table 2.3a, nurses and nursing students should genuinely communicate with empathy. Communicating honestly, genuinely, and authentically is powerful. It opens the door to creating true connections with others.Balchan, M. (2016). The Magic of Genuine Communication. http://michaelbalchan.com/communication/ Communicating with empathy has also been described as providing “unconditional positive regard.” Research has demonstrated that when health care teams communicate with empathy, there is improved patient healing, reduced symptoms of depression, and decreased medical errors.Morrison, E. (2019). Empathetic Communication in Healthcare. https://www.cibhs.org/sites/main/files/file-attachments/empathic_communication_in_healthcare_workbook.pdf?1594162691 Nurses and nursing students must be aware of potential barriers to communication. In addition to considering common communication barriers discussed in the previous section, there are several nontherapeutic responses to avoid. These responses often block the patient’s communication of their feelings or ideas. See Table 2.3b for a description of nontherapeutic responses.Burke, A. (2021). Therapeutic Communication: NCLEX-RN. https://www.registerednursing.org/nclex/therapeutic-communication/ Table 2.3b Nontherapeutic Responses \| Nontherapeutic Response \| Description \| \|---\|---\| \| Asking Personal Questions \| Asking personal questions that are not relevant to the situation is not professional or appropriate. Don’t ask questions just to satisfy your curiosity. For example, asking, “Why have you and Mary never married?” is not appropriate. A more therapeutic question would be, “How would you describe your relationship with Mary?” \| \| Giving Personal Opinions \| Giving personal opinions takes away the decision-making from the patient. Effective problem-solving must be accomplished by the patient and not the nurse. For example, stating, “If I were you, I’d put your father in a nursing home” is not therapeutic. Instead, it is more therapeutic to say, “Let’s talk about what options are available to your father.” \| \| Changing the Subject \| Changing the subject when someone is trying to communicate with you demonstrates lack of empathy and blocks further communication. It seems to say that you don’t care about what they are sharing. For example, stating, “Let’s not talk about your insurance problems; it’s time for your walk now” is not therapeutic. A more therapeutic response would be, “After your walk, let’s talk some more about what’s going on with your insurance company.” \| \| Stating Generalizations and Stereotypes \| Generalizations and stereotypes can threaten nurse-patient relationships. For example, it is not therapeutic to state the stereotype, “Older adults are always confused.” It is better to focus on the patient’s concern and ask, “Tell me more about your concerns about your father’s confusion.” \| \| Providing False Reassurances \| When a patient is seriously ill or distressed, the nurse may be tempted to offer hope with statements such as “You’ll be fine,” or “Don’t worry; everything will be alright.” These comments tend to discourage further expressions of feelings by the patient. A more therapeutic response would be, “It must be difficult not to know what the surgeon will find. What can I do to help?” \| \| Showing Sympathy \| Sympathy focuses on the nurse’s feelings rather than the patient. Saying “I’m so sorry about your amputation; I can’t imagine losing a leg.” This statement shows pity rather than trying to help the patient cope with the situation. A more therapeutic response would be, “The loss of your leg is a major change; how do you think this will affect your life?” \| \| Asking “Why” Questions \| A nurse may be tempted to ask the patient to explain “why” they believe, feel, or act in a certain way. However, patients and family members interpret “why” questions as accusations and become defensive. It is best to phrase a question by avoiding the word “why.” For example, instead of asking, “Why are you so upset?” it is better to rephrase the statement as, “You seem upset. What’s on your mind?” \| \| Approving or Disapproving \| Nurses should not impose their own attitudes, values, beliefs, and moral standards on others while in the professional nursing role. Judgmental messages contain terms such as “should,” “shouldn’t,” “ought to,” “good,” “bad,” “right,” or “wrong.” Agreeing or disagreeing sends the subtle message that nurses have the right to make value judgments about the patient’s decisions. Approving implies that the behavior being praised is the only acceptable one, and disapproving implies that the patient must meet the nurse’s expectations or standards. Instead, the nurse should help the patient explore their own beliefs and decisions. For example, it is nontherapeutic to state, “You shouldn’t consider elective surgery; there are too many risks involved.” A more therapeutic response would be, “So you are considering elective surgery. Tell me more about it…” gives the patient a chance to express their ideas or feelings without fear of being judged. \| \| Giving Defensive Responses \| When patients or family members express criticism, nurses should listen to what they are saying. Listening does not imply agreement. To discover reasons for the patient’s anger or dissatisfaction, the nurse should listen without criticism, avoid being defensive or accusatory, and attempt to defuse anger. For example, it is not therapeutic to state, “No one here would intentionally lie to you.” Instead, a more therapeutic response would be, “You believe people have been dishonest with you. Tell me more about what happened.” (After obtaining additional information, the nurse may elect to follow the chain of command at the agency and report the patient’s concerns for follow-up.) \| \| Providing Passive or Aggressive Responses \| Passive responses serve to avoid conflict or sidestep issues, whereas aggressive responses provoke confrontation. Nurses should use assertive communication as described in the “Basic Communication Concepts” section. \| \| Arguing \| Challenging or arguing against patient perceptions denies that they are real and valid to the other person. They imply that the other person is lying, misinformed, or uneducated. The skillful nurse can provide information or present reality in a way that avoids argument. For example, it is not therapeutic to state, “How can you say you didn’t sleep a wink when I heard you snoring all night long!” A more therapeutic response would be, “You don’t feel rested this morning? Let’s talk about ways to improve your rest.” \| Strategies for Effective Communication In addition to using therapeutic communication techniques, avoiding nontherapeutic responses, and overcoming common barriers to communication, there are additional strategies for promoting effective communication when providing patient-centered care. Specific questions to ask patients are as follows: - What concerns do you have about your plan of care? - What questions do you have about your medications? - Did I answer your question(s) clearly or is there additional information you would like?Smith, L. L. (2018, June 12). Strategies for effective patient communication. American Nurse. https://www.myamericannurse.com/strategies-for-effective-patient-communication/ Listen closely for feedback from patients. Feedback provides an opportunity to improve patient understanding, improve the patient-care experience, and provide high-quality care. Other suggestions for effective communication with hospitalized patients include the following: - Round with the providers and read progress notes from other health care team members to ensure you have the most up-to-date information about the patient’s treatment plan and progress. This information helps you to provide safe patient care as changes occur and also to accurately answer the patient’s questions. - Review information periodically with the patient to improve understanding. - Use patient communication boards in their room to set goals and communicate important reminders with the patient, family members, and other health care team members. This strategy can reduce call light usage for questions related to diet and activity orders and also gives patients and families the feeling that they always know the current plan of care. However, keep patient confidentiality in mind regarding information to publicly share on the board that visitors may see. - Provide printed information on medical procedures, conditions, and medications. It helps patients and family members to have multiple ways to provide information.Smith, L. L. (2018, June 12). Strategies for effective patient communication. American Nurse. https://www.myamericannurse.com/strategies-for-effective-patient-communication/ Adapting Your Communication When communicating with patients and family members, take note of your audience and adapt your message based on their characteristics such as age, developmental level, cognitive abilities, and any communication disorders. For patients with language differences, it is vital to provide trained medical interpreters when important information is communicated. Adapting communication according to the patient’s age and developmental level includes the following strategies: - When communicating with children, speak calmly and gently. It is often helpful to demonstrate what will be done during a procedure on a doll or stuffed animal. To establish trust, try using play or drawing pictures. - When communicating with adolescents, give freedom to make choices within established limits. - When communicating with older adults, be aware of potential vision and hearing impairments that commonly occur and address these barriers accordingly. For example, if a patient has glasses and/or hearing aids, be sure these devices are in place before communicating. See the following box for evidence-based strategies for communication with patients who have impaired hearing and vision.Butcher, H., Bulechek, G., Dochterman, J., & Wagner, C. (2018). Nursing interventions classification (NIC). Elsevier, pp. 115-116 Strategies for Communicating with Patients with Impaired Hearing and Vision Impaired Hearing - Gain the patient’s attention before speaking (e.g., through touch) - Minimize background noise - Position yourself 2-3 feet away from the patient - Facilitate lip-reading by facing the patient directly in a well-lit environment - Use gestures, when necessary - Listen attentively, allowing the patient adequate time to process communication and respond - Refrain from shouting at the patient - Ask the patient to suggest strategies for improved communication (e.g., speaking toward better ear and moving to well-lit area) - Face the patient directly, establish eye contact, and avoid turning away mid sentence - Simplify language (i.e., do not use slang but do use short, simple sentences), as appropriate - Note and document the patient’s preferred method of communication (e.g., verbal, written, lip-reading, or American Sign Language) in plan of care - Assist the patient in acquiring a hearing aid or assistive listening device - Refer to the primary care provider or specialist for evaluation, treatment, and hearing rehabilitationButcher, H., Bulechek, G., Dochterman, J., & Wagner, C. (2018). Nursing interventions classification (NIC). Elsevier, pp. 115-116 Impaired Vision - Identify yourself when entering the patient’s space - Ensure the patient’s eyeglasses or contact lenses have current prescription, are cleaned, and stored properly when not in use - Provide adequate room lighting - Minimize glare (i.e., offer sunglasses or draw window covering) - Provide educational materials in large print - Apply labels to frequently used items (i.e., mark medication bottles using high-contrasting colors) - Read pertinent information to the patient - Provide magnifying devices - Provide referral for supportive services (e.g., social, occupational, and psychological)Butcher, H., Bulechek, G., Dochterman, J., & Wagner, C. (2018). Nursing interventions classification (NIC). Elsevier, pp. 115-116 Patients with communication disorders require additional strategies to ensure effective communication. For example, aphasia is a communication disorder that results from damage to portions of the brain that are responsible for language. Aphasia usually occurs suddenly, often following a stroke or head injury, and impairs the patient’s expression and understanding of language. Global aphasia is caused by injuries to multiple language-processing areas of the brain, including those known as Wernicke’s and Broca’s areas. These brain areas are particularly important for understanding spoken language, accessing vocabulary, using grammar, and producing words and sentences. Individuals with global aphasia may be unable to say even a few words or may repeat the same words or phrases over and over again. They may have trouble understanding even simple words and sentences.National Institute on Deafness and Other Communication Disorders (NIDCD). (2017, March 6). Aphasia. https://www.nidcd.nih.gov/health/aphasia The most common type of aphasia is Broca’s aphasia. People with Broca’s aphasia often understand speech and know what they want to say, but frequently speak in short phrases that are produced with great effort. For example, they may intend to say, “I would like to go to the bathroom,” but instead the words, “Bathroom, Go,” are expressed. They are often aware of their difficulties and can become easily frustrated. See the hyperlink in the box below for evidence-based strategies to enhance communication with a person with impaired speech.Butcher, H., Bulechek, G., Dochterman, J., & Wagner, C. (2018). Nursing interventions classification (NIC). Elsevier, pp. 115-116. Strategies to Improve Communication with Patients with Impaired Speech - Modify the environment to minimize excess noise and decrease emotional distress - Phrase questions so the patient can answer using a simple “Yes” or “No,” being aware that patients with expressive aphasia may provide automatic responses that are incorrect - Monitor the patient for frustration, anger, depression, or other responses to impaired speech capabilities - Provide alternative methods of speech communication (e.g., writing tablet, flash cards, eye blinking, communication board with pictures and letters, hand signals or gestures, and computer) - Adjust your communication style to meet the needs of the patient (e.g., stand in front of the patient while speaking, listen attentively, present one idea or thought at a time, speak slowly but avoid shouting, use written communication, or solicit family’s assistance in understanding the patient’s speech) - Ensure the call light is within reach and central call light system is marked to indicate the patient has difficulty with speech - Repeat what the patient said to ensure accuracy - Instruct the patient to speak slowly - Collaborate with the family and a speech therapist to develop a plan for effective communicationButcher, H., Bulechek, G., Dochterman, J., & Wagner, C. (2018). Nursing interventions classification (NIC). Elsevier, pp. 115-116. Maintaining Patient Confidentiality When communicating with patients, their friends, their family members, and other members of the health care team, it is vital for the nurse to maintain patient confidentiality. The Health Insurance Portability and Accountability Act (HIPAA) provides standards for ensuring privacy of patient information that are enforceable by law. Nurses must always be aware of where and with whom they share patient information. For example, information related to patient care should not be discussed in public areas, paper charts must be kept in secure areas, computers must be logged off when walked away from, and patient information should only be shared with those directly involved in patient care. For more information about patient confidentiality, see the “Legal Considerations & Ethics” section in the “Scope of Practice” chapter. Read more information about the Health Insurance Portability and Accountability Act of 1996 (HIPAA). 2.4 Communicating with Health Care Team Members Open Resources for Nursing (Open RN) Professional communication with other members of the health care team is an important component of every nurse’s job. See Figure 2.8“1322557028-huge.jpg” by LightField Studios is used under license from Shutterstock.com for an image illustrating communication between health care team members. Common types of professional interactions include reports to health care team members, handoff reports, and transfer reports. Reports to Health Care Team Members Nurses routinely report information to other health care team members, as well as urgently contact health care providers to report changes in patient status. Standardized methods of communication have been developed to ensure that information is exchanged between health care team members in a structured, concise, and accurate manner to ensure safe patient care. One common format used by health care team members to exchange patient information is ISBARR, a mnemonic for the components of Introduction, Situation, Background, Assessment, Request/Recommendations, and Repeat back. - - Introduction: Introduce your name, role, and the agency from which you are calling. - Situation: Provide the patient’s name and location, why you are calling, recent vital signs, and the status of the patient. - Background: Provide pertinent background information about the patient such as admitting medical diagnoses, code status, recent relevant lab or diagnostic results, and allergies. - Assessment: Share abnormal assessment findings and your evaluation of the current patient situation. - Request/Recommendations: State what you would like the provider to do, such as reassess the patient, order a lab/diagnostic test, prescribe/change medication, etc. - Repeat back: If you are receiving new orders from a provider, repeat them to confirm accuracy. Be sure to document communication with the provider in the patient’s chart. Read an example of an ISBARR report in the following box. A hyperlink is provided to a printable ISBARR reference card. Sample ISBARR Report From a Nurse to a Health Care Provider I: “Hello Dr. Smith, this is Jane White, RN from the Med Surg unit.” S: “I am calling to tell you about Ms. White in Room 210, who is experiencing an increase in pain, as well as redness at her incision site. Her recent vital signs were BP 160/95, heart rate 90, respiratory rate 22, O2 sat 96%, and temperature 38 degrees Celsius. She is stable but her pain is worsening.” B: “Ms. White is a 65-year-old female, admitted yesterday post hip surgical replacement. She has been rating her pain at 3 or 4 out of 10 since surgery with her scheduled medication, but now she is rating the pain as a 7, with no relief from her scheduled medication of Vicodin 5/325 mg administered an hour ago. She is scheduled for physical therapy later this morning and is stating she won’t be able to participate because of the pain this morning.” A: “I just assessed the surgical site and her dressing was clean, dry, and intact, but there is 4 cm redness surrounding the incision, and it is warm and tender to the touch. There is moderate serosanguinous drainage. Otherwise, her lungs are clear and her heart rate is regular.” R: “I am calling to request an order for a CBC and increased dose of pain medication.” R: “I am repeating back the order to confirm that you are ordering a STAT CBC and an increase of her Vicodin to 10/325 mg.” View or print an ISBARR reference card . Handoff Reports Handoff reports are defined by The Joint Commission as “a transfer and acceptance of patient care responsibility achieved through effective communication. It is a real-time process of passing patient specific information from one caregiver to another, or from one team of caregivers to another, for the purpose of ensuring the continuity and safety of the patient’s care.”The Joint Commission. (n.d.). Sentinel event alert 58: Inadequate hand-off reports. https://www.jointcommission.org/resources/patient-safety-topics/sentinel-event/sentinel-event-alert-newsletters/sentinel-event-alert-58-inadequate-hand-off-communication/ In 2017, The Joint Commission issued a sentinel alert about inadequate handoff communication that has resulted in patient harm such as wrong-site surgeries, delays in treatment, falls, and medication errors. Strategies for improving handoff communication have been implemented at agencies across the country. Although many types of nursing shift-to-shift handoff reports have been used over the years, evidence strongly supports that bedside handoff reports increase patient safety, as well as patient and nurse satisfaction, by effectively communicating current, accurate patient information in real time.Dorvil, B. (2018). The secrets to successful nurse bedside shift report implementation and sustainability. Nursing Management, 49(6), 20-25. https://doi.org/10.1097/01.NUMA.0000533770.12758.44 See Figure 2.9“618721604-huge” by Rido is used under license from Shutterstock.com. for an image illustrating two nurses participating in a handoff report. Bedside reports typically occur in hospitals and include the patient, along with the off-going and the oncoming nurses in a face-to-face handoff report conducted at the patient’s bedside. HIPAA rules must be kept in mind if visitors are present or the room is not a private room. Family members may be included with the patient’s permission. See a sample checklist for a bedside handoff report from the Agency for Healthcare Research and Quality in Figure 2.10.“Strat3_Tool_2_Nurse_Chklst_508.pdf” by AHRQ is licensed under CC0 Although a bedside handoff report is similar to an ISBARR report, it contains additional information to ensure continuity of care across nursing shifts. For example, the “assessment” portion of the bedside handoff report includes detailed pertinent data the oncoming nurse needs to know, such as current head-to-toe assessment findings to establish a baseline; information about equipment such as IVs, catheters, and drainage tubes; and recent changes in medications, lab results, diagnostic tests, and treatments. View Sample Information to Include in a Shift Report. View a video on creating shift reports.RegisteredNurseRN. (2015, May 23). Nursing shift report sheet templates \| How to give a nursing shift report. [Video]. YouTube. All rights reserved. Video used with permission. https://youtu.be/X76iKFQhPNw Transfer Reports Transfer reports are provided by nurses when transferring a patient to another unit or to another agency. Transfer reports contain similar information as bedside handoff reports, but are even more detailed when the patient is being transferred to another agency. Checklists are often provided by agencies to ensure accurate, complete information is shared. 2.5 Documentation Open Resources for Nursing (Open RN) Using Technology to Access Information Most patient information in acute care, long-term care, and other clinical settings is now electronic and uses intranet technology for secure access by providers, nurses, and other health care team members to maintain patient confidentiality. Intranet refers to a private computer network within an institution. An electronic health record (EHR) is a real-time, patient-centered record that makes information available instantly and securely to authorized users.HealthIT.gov. (2019, September 10). What is an electronic health record (EHR)? https://www.healthit.gov/faq/what-electronic-health-record-ehr Computers used to access an EHR can be found in patient rooms, on wheeled carts, in workstations, or even on handheld devices. See Figure 2.11“Winn_Army_Community_Hospital_Pharmacy_Stays_Online_During_Power_Outage.jpg” by Flickr user MC4 Army is licensed under CC BY 2.0 for an image of a nurse documenting in an EHR. The EHR for each patient contains a great deal of information. The most frequent pieces of information that nurses access include the following: - History and Physical (H&P): A history and physical (H&P) is a specific type of documentation created by the health care provider when the patient is admitted to the facility. An H&P includes important information about the patient’s current status, medical history, and the treatment plan in a concise format that is helpful for the nurse to review. Information typically includes the reason for admission, health history, surgical history, allergies, current medications, physical examination findings, medical diagnoses, and the treatment plan. - Provider orders: This section includes the prescriptions, or medical orders, that the nurse must legally implement or appropriately communicate according to agency policy if not implemented. - Medication Administration Records (MARs): Medications are charted through electronic medication administration records (MARs). These records interface the medication orders from providers with pharmacists and are also the location where nurses document medications administered. - Treatment Administration Records (TARs): In many facilities, treatments are documented on a treatment administration record. - Laboratory results: This section includes results from blood work and other tests performed in the lab. - Diagnostic test results: This section includes results from diagnostic tests ordered by the provider such as X-rays, ultrasounds, etc. - Progress notes: This section contains notes created by nurses and other health care providers regarding patient care. It is helpful for the nurse to review daily progress notes by all team members to ensure continuity of care. View a video of how to read a patient’s chart.RegisteredNurseRN. (2015, October 16). Charting for nurses \| How to understand a patient’s chart as a nursing student or new nurse. [Video]. YouTube. All rights reserved. Video used with permission. https://youtu.be/lNwRvKaNsGc Legal Documentation Nurses and health care team members are legally required to document care provided to patients. In a court of law, the rule of thumb used is, “If it wasn’t documented, it wasn’t done.” Documentation should be objective, factual, professional, and use proper medical terminology, grammar, and spelling. All types of documentation must include the date, time, and signature of the person documenting. Any type of documentation in the EHR is considered a legal document and must be completed in an accurate and timely manner. Abbreviations should be avoided in legal documentation. Documentation is used for many purposes. It is used to ensure continuity of care across health care team members and across shifts; monitor standards of care for quality assurance activities; and provide information for reimbursement purposes by insurance companies, Medicare, and Medicaid. Documentation may also be used for research purposes or, in some instances, for legal concerns in a court of law. Documentation by nurses includes recording patient assessments, writing progress notes, and creating or addressing information included in nursing care plans. Nursing care plans are further discussed in the “Planning” section of the “Nursing Process” chapter. Common Types of Documentation Common formats used to document patient care include charting by exception, focused DAR notes, narrative notes, SOAPIE progress notes, patient discharge summaries, and Minimum Data Set (MDS) charting. Charting by Exception Charting by exception (CBE) documentation was designed to decrease the amount of time required to document care. CBE contains a list of normal findings. After performing an assessment, nurses confirm normal findings on the list found on assessment and write only brief progress notes for abnormal findings or to document communication with other team members. Focused DAR Notes Focused DAR notes are a type of progress note that are commonly used in combination with charting by exception documentation. DAR stands for Data, Action, and Response. Focused DAR notes are brief. Each note is focused on one patient problem for efficiency in documenting and reading. - Data: This section contains information collected during the patient assessment, including vital signs and physical examination findings found during the “Assessment” phase of the nursing process. The Assessment phase is further discussed in the “Nursing Process” chapter. - Action: This section contains the nursing actions that are planned and implemented for the patient’s focused problem. This section correlates to the “Planning” and “Implementation” phases of the nursing process and are further discussed in the “Nursing Process” chapter. - Response: This section contains information about the patient’s response to the nursing actions and evaluates if the planned care was effective. This section correlates to the “Evaluation” phase of the nursing process that is further discussed in the “Nursing Process” chapter. View sample charting by exception paper documentation with associated DAR notes for abnormal findings. For more information about writing DAR notes, visit What is F-DAR Charting? View a video explaining F-DAR charting.RegisteredNurseRN. (2015, October 27). FDAR for nurses \| How to chart in F-DAR format with examples. [Video]. YouTube. All rights reserved. Video used with permission. https://youtu.be/BXf7wj9Wmfc Narrative Notes Narrative notes are a type of progress note that chronicles assessment findings and nursing activities for the patient that occurred throughout the entire shift or visit. View sample narrative note documentation according to body system in each assessment chapter of the Open RN Nursing Skills textbook. SOAPIE Notes SOAPIE is a mnemonic for a type of progress note that is organized by six categories: Subjective, Objective, Assessment, Plan, Interventions, and Evaluation. SOAPIE progress notes are written by nurses, as well as other members of the health care team. - Subjective: This section includes what the patient said, such as, “I have a headache.” It can also contain information related to pertinent medical history and why the patient is in need of care. - Objective: This section contains the observable and measurable data collected during a patient assessment, such as the vital signs, physical examination findings, and lab/diagnostic test results. - Assessment: This section contains the interpretation of what was noted in the Subjective and Objective sections, such as a nursing diagnosis in a nursing progress note or the medical diagnosis in a progress note written by a health care provider. - Plan: This section outlines the plan of care based on the Assessment section, including goals and planned interventions. - Interventions: This section describes the actions implemented. - Evaluation: This section describes the patient response to interventions and if the planned outcomes were met. Patient Discharge Summary When a patient is discharged from an agency, a discharge summary is documented in the patient record, along with clear verbal and written patient education and instructions provided to the patient. Discharge summary information is frequently provided in a checklist format to ensure accuracy and includes the following: - Time of departure and method of transportation out of the hospital (e.g., wheelchair) - Name and relationship of person accompanying the patient at discharge - Condition of the patient at discharge - Patient education completed and associated educational materials or other information provided to the patient - Discharge instructions on medications, treatments, diet, and activity - Follow-up appointments or referrals given See Figure 2.12“1934626790-huge.jpg” by TommyStockProject is used under license from Shutterstock.com for an image of a nurse providing discharge instructions to a patient. Discharge teaching typically starts at admission and continues throughout the patient’s stay. Minimum Data Set (MDS) Charting In long-term care settings, additional documentation is used to provide information for reimbursement by private insurance, Medicare, and Medicaid. The Resident Assessment Instrument Minimum Data Set (MDS) is a federally mandated assessment tool created by registered nurses in skilled nursing facilities to track a patient’s goal achievement, as well as to coordinate the efforts of the health care team to optimize the resident’s quality of care and quality of life.Centers for Medicare & Medicaid Services. (2019, October). Long-term care facility resident assessment instrument 3.0 user’s manual. https://downloads.cms.gov/files/mds-3.0-rai-manual-v1.17.1_october_2019.pdf This tool also guides nursing care plan development. 2.6 Putting It All Together Patient Scenario Mr. Hernandez is a 47-year-old patient admitted to the neurological trauma floor as the result of a motor vehicle accident two days ago. The patient sustained significant facial trauma in the accident and his jaw is wired shut. His left eye is currently swollen, and he had significant bruising to the left side of his face. The nurse completes a visual assessment and notes that the patient has normal extraocular movement, peripheral vision, and pupillary constriction bilaterally. Additional assessment reveals that Mr. Hernandez also sustained a fracture of the left arm and wrist during the accident. His left arm is currently in a cast and sling. He has normal movement and sensation with his right hand. Mrs. Hernandez is present at the patient’s bedside and has provided additional information about the patient. She reports that Mr. Hernandez’s primary language is Spanish but that he understands English well. He has a bachelor’s degree in accounting and owns his own accounting firm. He has a history of elevated blood pressure, but is otherwise healthy. The nurse notes that the patient’s jaw is wired and he is unable to offer a verbal response. He does understand English well, has appropriate visual acuity, and is able to move his right hand and arm. Based on the assessment information that has been gathered, the nurse plans several actions to enhance communication. Adaptive communication devices such as communication boards, symbol cards, or electronic messaging systems will be provided. The nurse will eliminate distractions such as television and hallway noise to decrease sources of additional stimuli in the communication experience. Sample Documentation Mr. Hernandez has impaired verbal communication due to facial fracture and inability to enunciate words around his wired jaw. He understands both verbal and written communication. Mr. Hernandez has left sided facial swelling, but no visual impairment. He has a left arm fracture but is able to move and write with his right hand. The patient is supplied with communication cards and marker board. He responds appropriately with written communication and is able to signal his needs. 2.7 Learning Activities Open Resources for Nursing (Open RN) Learning Activities (Answers to “Learning Activities” can be found in the “Answer Key” at the end of the book. Answers to interactive activity elements will be provided within the element as immediate feedback.) Practice what you have learned in this chapter by completing these learning activities. When accessing the online activities that contain videos, it is best to use Google Chrome or Firefox browsers. 1. To test understanding of these terms, try an online quiz: Therapeutic Communication Techniques vs. Non-therapeutic Communication Techniques Quizlet 2. Consider the following scenario and describe actions that you might take to facilitate the patient communication experience. You are caring for Mr. Curtis, an 87-year-old patient newly admitted to the medical surgical floor with a hip fracture. You approach the room, knock at the door, complete hand hygiene, and enter. Upon entry, you see Mr. Curtis is in bed surrounded by multiple family members. The television is on in the background and you also note the sound of meal trays being delivered in the hallway. Based on the described scenario, what actions might be implemented to aid in your communication with Mr. Curtis? An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=342#h5p-61 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=342#h5p-84 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=342#h5p-85 II Glossary Open Resources for Nursing (Open RN) Aphasia: A communication disorder that results from damage to portions of the brain that are responsible for language. Assertive communication: A way to convey information that describes the facts, the sender’s feelings, and explanations without disrespecting the receiver’s feelings. This communication is often described as using “I” messages: “I feel…,” “I understand…,” or “Help me to understand…” Bedside nurse handoff report: A handoff report in hospitals that involves patients, their family members, and both the off-going and the incoming nurses. The report is performed face to face and conducted at the patient’s bedside. Broca’s aphasia: A type of aphasia where patients understand speech and know what they want to say, but frequently speak in short phrases that are produced with great effort. People with Broca’s aphasia typically understand the speech of others fairly well. Because of this, they are often aware of their difficulties and can become easily frustrated. Charting by exception: A type of documentation where a list of “normal findings” is provided and nurses document assessment findings by confirming normal findings and writing brief documentation notes for any abnormal findings. DAR: A type of documentation often used in combination with charting by exception. DAR stands for Data, Action, and Response. Focused DAR notes are brief, and each note is focused on one patient problem for efficiency in documenting, as well as for reading. Electronic Health Record (EHR): A digital version of a patient’s paper chart. EHRs are real-time, patient-centered records that make information available instantly and securely to authorized users. Global aphasia: A type of aphasia that results from damage to extensive portions of the language areas of the brain. Individuals with global aphasia have severe communication difficulties and may be extremely limited in their ability to speak or comprehend language. They may be unable to say even a few words or may repeat the same words or phrases over and over again. They may have trouble understanding even simple words and sentences. Handoff report: A process of exchanging vital patient information, responsibility, and accountability between the off-going and incoming nurses in an effort to ensure safe continuity of care and the delivery of best clinical practices. ISBARR: A mnemonic for the format of professional communication among health care team members that includes Introduction, Situation, Background, Assessment, Request/Recommendations, and Repeat back. Minimum Data Set (MDS): A federally mandated assessment tool used in skilled nursing facilities to track a patient’s goal achievement, as well as to coordinate the efforts of the health care team to optimize the resident’s quality of care and quality of life. Narrative note: A type of documentation that chronicles all of the patient’s assessment findings and nursing activities that occurred throughout the shift. Nontherapeutic responses: Responses to patients that block communication, expression of emotion, or problem-solving. Progressive relaxation: Types of relaxation techniques that focus on reducing muscle tension and using mental imagery to induce calmness. Relaxation breathing: A breathing technique used to reduce anxiety and control the stress response. SOAPIE: A mnemonic for a type of documentation that is organized by six categories: Subjective, Objective, Assessment, Plan, Interventions, and Evaluation. Therapeutic communication: The purposeful, interpersonal information transmitting process through words and behaviors based on both parties’ knowledge, attitudes, and skills, which leads to patient understanding and participation. Therapeutic communication techniques: Techniques that encourage patients to explore feelings, problem solve, and cope with responses to medical conditions and life events. Verbal communication: Exchange of information using words understood by the receiver. Diverse Patients III 3.1 Diverse Patients Introduction Open Resources for Nursing (Open RN) Learning Objectives - Reflect upon personal and cultural values, beliefs, biases, and heritageAmerican Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association - Embrace diversity, equity, inclusivity, health promotion, and health care for individuals of diverse geographic, cultural, ethnic, racial, gender, and spiritual backgrounds across the life spanAmerican Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association - Demonstrate respect, equity, and empathy in actions and interactions with all health care consumersAmerican Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association - Participate in life-long learning to understand cultural preferences, worldviews, choices, and decision-making processes of diverse patientsAmerican Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association - Protect patient dignity - Demonstrate principles of patient-centered care and cultural humility - Make adaptations to patient care to reduce health disparities - Adhere to the Patient’s Bill of Rights - Identify strategies to advocate for patients - Use evidence-based practices No matter who we are or where we come from, every person belongs to a culture. The impact of culture on a person’s health is profound because it affects many health beliefs, such as perceived causes of illness, ways to prevent illness, and acceptance of medical treatments. Culturally responsive care integrates these cultural beliefs into an individual’s health care. Culturally responsive care is intentional and promotes trust and rapport with patients. At its heart, culturally responsive care is patient-centered care. The American Nurses Association (ANA) states, “The art of nursing is demonstrated by unconditionally accepting the humanity of others, respecting their need for dignity and worth, while providing compassionate, comforting care.”American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association Nurses provide holistic care when incorporating their patients’ physical, mental, spiritual, cultural, and social needs into their health care (referred to as holism). As a nursing student, you are undertaking a journey of developing cultural competency with an attitude of cultural humility as you learn how to provide holistic care to your patients. Cultural competency is a lifelong process of applying evidence-based nursing in agreement with the cultural values, beliefs, worldview, and practices of patients to produce improved patient outcomes.Centers for Disease Control and Prevention. (2020, October 21). Cultural competence in health and human services. https://npin.cdc.gov/pages/cultural-competence,Curtis, E., Jones, R., Tipene-Leach, D., Walker, C., Loring, B., Paine, S.-J., & Reid, P. (2019). Why cultural safety rather than cultural competency is required to achieve health equity: A literature review and recommended definition. International Journal for Equity in Health, 18, 174. https://doi.org/10.1186/s12939-019-1082-3,Young, S., & Guo, K. (2016). Cultural diversity training: The necessity for cultural competence for healthcare providers and in nursing practice. The Health Care Manager, 35(2), 94-102. https://doi.org/10.1097/hcm.0000000000000100 Cultural humility is defined by the American Nurses Association as, “A humble and respectful attitude toward individuals of other cultures that pushes one to challenge their own cultural biases, realize they cannot know everything about other cultures, and approach learning about other cultures as a life-long goal and process.American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association The bottom line is you will improve the quality of your nursing care by understanding, respecting, and responding to a patient’s experiences, values, beliefs, and preferences.U.S. Department of Health and Human Services. (n.d.). Cultural and Linguistically Appropriate Services (CLAS) in Maternal Health Care. https://thinkculturalhealth.hhs.gov/ This chapter will focus on developing culturally competency and cultural humility and providing culturally responsive care. 3.2 Diverse Patients Basic Concepts Open Resources for Nursing (Open RN) Let’s begin the journey of developing cultural competency by exploring basic concepts related to culture. Culture and Subculture Culture is a set of beliefs, attitudes, and practices shared by a group of people or community that is accepted, followed, and passed down to other members of the group. The word “culture” may at times be interchanged with terms such as ethnicity, nationality, or race. See Figure 3.1“Cultural diversity large.jpg” by მარიამ იაკობაძე is licensed under CC BY-SA 4.0 for an illustration depicting culture by various nationalities. Cultural beliefs and practices bind group or community members together and help form a cohesive identity.Curtis, E., Jones, R., Tipene-Leach, D., Walker, C., Loring, B., Paine, S.-J., & Reid, P. (2019). Why cultural safety rather than cultural competency is required to achieve health equity: A literature review and recommended definition. International Journal for Equity in Health, 18, 174. https://doi.org/10.1186/s12939-019-1082-3,Young, S., & Guo, K. (2016). Cultural diversity training: The necessity for cultural competence for healthcare providers and in nursing practice. The Health Care Manager, 35(2), 94-102. https://doi.org/10.1097/hcm.0000000000000100 Culture has an enduring influence on a person’s view of the world, expressed through language and communication patterns, family connections and kinship, religion, cuisine, dress, and other customs and rituals.Campinha-Bacote, J. (2011). Coming to know cultural competence: An evolutionary process. International Journal for Human Caring, 15(3), 42-48. Culture is not static but is dynamic and ever-changing; it changes as members come into contact with beliefs from other cultures. For example, sushi is a traditional Asian dish that has become popular in America in recent years. Nurses and other health care team members are impacted by their own personal cultural beliefs. For example, a commonly held belief in American health care is the importance of timeliness; medications are administered at specifically scheduled times, and appearing for appointments on time is considered crucial. Most cultural beliefs are a combination of beliefs, values, and habits that have been passed down through family members and authority figures. The first step in developing cultural competence is to become aware of your own cultural beliefs, attitudes, and practices. Nurses should also be aware of subcultures. A subculture is a smaller group of people within a culture, often based on a person’s occupation, hobbies, interests, or place of origin. People belonging to a subculture may identify with some, but not all, aspects of their larger “parent” culture. Members of the subculture share beliefs and commonalities that set them apart and do not always conform with those of the larger culture. See Table 3.2a for examples of subcultures. Table 3.2a Examples of Subcultures \| Age/Generation \| Baby Boomers, Millennials, Gen Z \| \|---\|---\| \| Occupation \| Truck Driver, Computer Scientist, Nurse \| \| Hobbies/Interests \| Birdwatchers, Gamers, Foodies, Skateboarders \| \| Religion \| Hinduism, Baptist, Islam \| \| Gender \| Male, Female, Nonbinary, Two-Spirit \| \| Geography \| Rural, Urban, Southern, Midwestern \| Culture is much more than a person’s nationality or ethnicity. Culture can be expressed in a multitude of ways, including the following: - Language(s) spoken - Religion and spiritual beliefs - Gender identity - Socioeconomic status - Age - Sexual orientation - Geography - Educational background - Life experiences - Living situation - Employment status - Immigration status - Ability/Disability People typically belong to more than one culture simultaneously. These cultures overlap, intersect, and are woven together to create a person’s cultural identity. In other words, the many ways in which a person expresses their cultural identity are not separated, but are closely intertwined, referred to as intersectionality. Assimilation Assimilation is the process of adopting or conforming to the practices, habits, and norms of a cultural group. As a result, the person gradually takes on a new cultural identity and may lose their original identity in the process.Cole, N. L. (2018). How different cultural groups become more alike: Definition, overview and theories of assimilation. ThoughtCo. https://www.thoughtco.com/assimilation-definition-4149483 An example of assimilation is a newly graduated nurse, who after several months of orientation on the hospital unit, offers assistance to a colleague who is busy. The new nurse has developed self-confidence in the role and has developed an understanding that helping others is a norm for the nurses on that unit. Assimilation is not always voluntary, however, and may become a source of distress. There are historic examples of involuntary assimilation in many countries. For example, in the past, authorities in the United States and Canadian governments required indigenous children to attend boarding schools, separated them from their families, and punished them for speaking their native language.The Truth and Reconciliation Commission of Canada.(2015). Honoring the truth, reconciling for the future: A summary of the final report of the truth and reconciliation commission of Canada. http://www.trc.ca/assets/pdf/Honouring_the_Truth_Reconciling_for_the_Future_July_23_2015.pdf,Smith, A. (2007, March 26). Soul wound: The legacy of Native American schools. Amnesty International Magazine. https://web.archive.org/web/20121206131053/http://www.amnestyusa.org/node/87342 Cultural Values and Beliefs Culture provides an important source of values and comfort for patients, families, and communities. Think of culture as a thread that is woven through a person’s world and impacts one’s choices, perspectives, and way of life. It plays a role in all of a person’s life events and threads its way through the development of one’s self-concept, sexuality, and spirituality. It affects lifelong nutritional habits, as well as coping strategies with death and dying. Culture influences how a patient interprets “good” health, as well as their perspectives on illness and the causes of illness. The manner in which pain is expressed is also shaped by a person’s culture. See Table 3.2b for additional examples of how a person’s culture impacts common values and beliefs regarding family patterns, communication patterns, space orientation, time orientation, and nutritional patterns. As you read Table 3.2b, take a moment to reflect on your own cultural background and your personally held beliefs for each of these concepts. Table 3.2b Cultural Concepts \| Cultural Concepts \| Examples of Culturally Influenced Values and Beliefs \| \|---\|---\| \| Family Patterns \| Family size Views on contraception Roles of family members Naming customs Value placed on elders and children Discipline/upbringing of children Rites of passage End-of-life care \| \| Communication Patterns \| Eye contact Touch Use of silence or humor Intonation, vocabulary, grammatical structure Topics considered personal (i.e., difficult to discuss) Greeting customs (handshakes, hugs) \| \| Space Orientation \| Personal distance and intimate space \| \| Time Orientation \| Focus on the past, present, or future Importance of following a routine or schedule Arrival on time for appointments \| \| Nutritional Patterns \| Common meal choices Foods to avoid Foods to heal or treat disease Religious practices (e.g., fasting, dietary restrictions) Foods to celebrate life events and holidays \| A person’s culture can also affect encounters with health care providers in other ways, such as the following: - Level of family involvement in care - Timing for seeking care - Acceptance of treatment (as preventative measure or for an actual health problem) - The accepted decision-maker (i.e., the patient or other family members) - Use of home or folk remedies - Seeking advice or treatment from nontraditional providers - Acceptance of a caregiver of the opposite gender Cultural Diversity and Cultural Humility Cultural diversity is a term used to describe cultural differences among people. See Figure 3.2“Pure_Diversity,_Mirta_Toledo_1993.jpg” by Mirta Toledo is licensed under CC BY-SA 4.0 for artwork depicting diversity. While it is useful to be aware of specific traits of a culture or subculture, it is just as important to understand that each individual is unique and there are always variations in beliefs among individuals within a culture. Nurses should, therefore, refrain from making assumptions about the values and beliefs of members of specific cultural groups.Young, S., & Guo, K. (2016). Cultural diversity training: The necessity for cultural competence for healthcare providers and in nursing practice. The Health Care Manager, 35(2), 94-102. https://doi.org/10.1097/hcm.0000000000000100 Instead, a better approach is recognizing that culture is not a static, uniform characteristic but instead realizing there is diversity within every culture and in every person. The American Nurses Association (ANA) defines cultural humility as, “A humble and respectful attitude toward individuals of other cultures that pushes one to challenge their own cultural biases, realize they cannot possibly know everything about other cultures, and approach learning about other cultures as a lifelong goal and process.”American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association Current demographics in the United States reveal that the population is predominantly white. People who were born in another country, but now live in the United States, comprise approximately 14% of the nation’s total population. However, these demographics are rapidly changing. The United States Census Bureau projects that more than 50 percent of Americans will belong to a minority group by 2060. With an increasingly diverse population to care for, it is imperative for nurses to integrate culturally responsive care into their nursing practice.Young, S., & Guo, K. (2016). Cultural diversity training: The necessity for cultural competence for healthcare providers and in nursing practice. The Health Care Manager, 35(2), 94-102. https://doi.org/10.1097/hcm.0000000000000100,Kaihlanen, A. M., Hietapakka, L., & Heponiemi, T. (2019) Increasing cultural awareness: Qualitative study of nurses’ perceptions about cultural competence training. BMC Nursing, 18(1), 1–9. https://doi.org/10.1186/s12912-019-0363-x Creative a culturally responsive environment is discussed in a later subsection of this chapter. Concepts Related to Culture There are additional concepts related to culture that can impact a nurse’s ability to provide culturally responsive care, including stereotyping, ethnocentrism, discrimination, prejudice, and bias. See Table 3.2c for definitions and examples of these concepts. Table 3.2c Concepts Related to Culture \| Concepts \| Definitions \| Examples \| \|---\|---\|---\| \| Stereotyping \| The assumption that a person has the attributes, traits, beliefs, and values of a cultural group because they are a member of that group. \| The nurse teaches the daughter of an older patient how to make online doctor appointments, assuming that the older patient does not understand how to use a computer. \| \| Ethnocentrism \| The belief that one’s culture (or race, ethnicity, or country) is better and preferable than another’s. \| The nurse disparages the patient’s use of nontraditional medicine and tells the patient that traditional treatments are superior. \| \| Discrimination \| The unfair and different treatment of another person or group, denying them opportunities and rights to participate fully in society. \| A nurse manager refuses to hire a candidate for a nursing position because she is pregnant. \| \| Prejudice \| A prejudgment or preconceived idea, often unfavorable, about a person or group of people. \| The nurse withholds pain medication from a patient with a history of opioid addiction. \| \| Bias \| An attitude, opinion, or inclination (positive or negative) towards a group or members of a group. Bias can be a conscious attitude (explicit) or an unconscious attitude where the person is not aware of their bias (implicit). \| A patient does not want the nurse to care for them because the nurse has a tattoo. \| Race is a socially constructed idea because there are no true genetically- or biologically-distinct races. Humans are not biologically different from each other. Racism presumes that races are distinct from one another, and there is a hierarchy to race, implying that races are unequal. Ernest Grant, president of the American Nurses Association (ANA), recently declared that nurses are obligated “to speak up against racism, discrimination, and injustice. This is non-negotiable.”American Nurses Association. (2020, June 1). ANA president condemns racism, brutality and senseless violence against black communities. https://www.nursingworld.org/news/news-releases/2020/ana-president-condemns-racism-brutality-and-senseless-violence-against-black-communities/ As frontline health care providers, nurses have an obligation to recognize the impact of racism on their patients and the communities they serve.Fulbright-Sumpter, D. (2020). “But I’m not racist …” The nurse’s role in dismantling institutionalized racism. Texas Nursing, 94(3), 14–17. Sexual orientation refers to a person’s physical and emotional interest or desire for others. Sexual orientation is on a continuum and is manifested in one’s self-identity and behaviors.Brydum, S. (2015, July 31). The true meaning of the word cisgender. The Advocate. https://www.advocate.com/transgender/2015/07/31/true-meaning-word-cisgender The acronym LGBTQ stands for lesbian, gay, bisexual, transgender, queer, or questioning in reference to sexual orientation. (A “+” is sometimes added after LGBTQ to capture additional orientations). See Figure 3.3“Dublin_LGBTQ_Pride_Festival_2013_-_LGBT_Rights_Matter_(9183564890).jpg” by infomatique is licensed under CC BY-SA 2.0 for an image of participants in a LGBTQ rally in Dublin. Historically, individuals within the LGBTQ community have experienced discrimination and prejudice from health care providers and avoided or delayed health care due to these negative experiences. Despite increased recognition of this group of people in recent years, members of the LGBTQ community continue to experience significant health disparities. Persistent cultural bias and stigmatization of lesbian, gay, bisexual, or transgender (LGBTQ) people have also been shown to contribute to higher rates of substance abuse and suicide rates in this population.Cole, N. L. (2018). How different cultural groups become more alike: Definition, overview and theories of assimilation. ThoughtCo. https://www.thoughtco.com/assimilation-definition-4149483,U.S. Department of Health and Human Services. Healthy People 2020. Lesbian, gay, bisexual, and transgender health. https://www.healthypeople.gov/2020/topics-objectives/topic/lesbian-gay-bisexual-and-transgender-health,Chance, T. F. (2013). Going to pieces over LGBT health disparities: How an amended affordable care act could cure the discrimination that ails the LGBT community. Journal of Health Care Law and Policy, 16(2), 375–402. https://digitalcommons.law.umaryland.edu/cgi/viewcontent.cgi?article=1309&context=jhclp Gender identity refers to a person’s inner sensibility that they are a man, a woman, or perhaps neither. The true meaning of the word cisgender. The Advocate. https://www.advocate.com/transgender/2015/07/31/true-meaning-word-cisgender To the extent that a person’s gender identity does not conform with the sex assigned to them at birth, they may identify as transgender or as gender nonbinary. Transgender people, like cisgender people, “may be sexually oriented toward men, women, both sexes, or neither sex.”Meerwijk, E. L., & Sevelius, J. M. (2017). Transgender population size in the United States: A meta-regression of population-based probability samples. American Journal of Public Health, 107(2), e1–e8. https://doi.org/10.2105/AJPH.2016.303578 Gender expression refers to a person’s outward demonstration of gender in relation to societal norms, such as in style of dress, hairstyle, or other mannerisms.Keuroghlian, A. S., Ard, K. L., & Makadon, H. J. (2017). Advancing health equity for lesbian, gay, bisexual and transgender (LGBT) people through sexual health education and LGBT-affirming health care environments. Sexual Health, 14(1), 119–122. https://doi.org/10.1071/SH16145Sharing pronouns as part of a basic introduction to a patient can assist a transgender patient to feel secure sharing their pronouns in a health care setting. Asking a patient for their pronoun (he, she, they, ze, etc.) is considered part of a nursing assessment. Related Ethical Considerations Justice, a principle and moral obligation to act on the basis of equality and equity, is a standard linked to fairness for all in society.American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association The ANA states this obligation guarantees not only basic rights (respect, human dignity, autonomy, security, and safety) but also fairness in all operations of societal structures. This includes care being delivered with fairness, rightness, correctness, unbiasedness, and inclusiveness while being based on well-founded reason and evidence.American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association Social justice is related to respect, equity, and inclusion. The ANA defines social justice as equal rights, equal treatment, and equitable opportunities for all.American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association The ANA further states, “Nurses need to model the profession’s commitment to social justice and health through actions and advocacy to address the social determinants of health and promote well-being in all settings within society.”American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association Social determinants of health are nonmedical factors that influence health outcomes, including conditions in which people are born, grow, work, live, and age, and the wider sets of forces and systems shaping the conditions of daily life.American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association Health outcomes impacted by social determinants of health are referred to as health disparities. Health disparities are further discussed in a subsection later in this chapter. 3.3 Patient’s Bill of Rights Open Resources for Nursing (Open RN) Th Patient’s Bill of Rights is an evolving document related to providing culturally competent care. In 1973 the American Hospital Association (AHA) adopted the Patient’s Bill of Rights.American Hospital Association. (2003). The patient care partnership. https://www.aha.org/other-resources/patient-care-partnership See the following box to review the original Patient’s Bill of Rights. The bill has since been updated, revised, and adapted for use throughout the world in all health care settings. There are different versions of the bill, but, in general, it safeguards a patient’s right to accurate and complete information, fair treatment, and self-determination when making health care decisions. Patients should expect to be treated with sensitivity and dignity and with respect for their cultural values. While the Patient’s Bill of Rights extends beyond the scope of cultural considerations, its basic principles underscore the importance of cultural competency when caring for people. Patient’s Bill of RightsAmerican Hospital Association. (2003). The patient care partnership. https://www.aha.org/other-resources/patient-care-partnership - The patient has the right to considerate and respectful care. - The patient has the right to and is encouraged to obtain from physicians and other direct caregivers relevant, current, and understandable information concerning diagnosis, treatment, and prognosis. - Except in emergencies when the patient lacks decision-making capacity and the need for treatment is urgent, the patient is entitled to the opportunity to discuss and request information related to the specific procedures and/or treatments, the risks involved, the possible length of recuperation, and the medically reasonable alternatives and their accompanying risks and benefits. - Patients have the right to know the identity of physicians, nurses, and others involved in their care, as well as when those involved are students, residents, or other trainees. - The patient has the right to know the immediate and long-term financial implications of treatment choices, insofar as they are known. - The patient has the right to make decisions about the plan of care prior to and during the course of treatment and to refuse a recommended treatment or plan of care to the extent permitted by law and hospital policy and to be informed of the medical consequences of this action. In case of such refusal, the patient is entitled to other appropriate care and services that the hospital provides or transfer to another hospital. The hospital should notify patients of any policy that might affect patient choice within the institution. - The patient has the right to have an advance directive (such as a living will, health care proxy, or durable power of attorney for health care) concerning treatment or designating a surrogate decision-maker with the expectation that the hospital will honor the intent of that directive to the extent permitted by law and hospital policy. Health care institutions must advise patients of their rights under state law and hospital policy to make informed medical choices, ask if the patient has an advance directive, and include that information in patient records. The patient has the right to timely information about hospital policy that may limit its ability to implement fully a legally valid advance directive. - The patient has the right to every consideration of privacy. Case discussion, consultation, examination, and treatment should be conducted so as to protect each patient’s privacy. - The patient has the right to expect that all communications and records pertaining to his/her care will be treated as confidential by the hospital, except in cases such as suspected abuse and public health hazards when reporting is permitted or required by law. The patient has the right to expect that the hospital will emphasize the confidentiality of this information when it releases it to any other parties entitled to review information in these records. - The patient has the right to review the records pertaining to his/her medical care and to have the information explained or interpreted as necessary, except when restricted by law. - The patient has the right to expect that, within its capacity and policies, a hospital will make a reasonable response to the request of a patient for appropriate and medically indicated care and services. The hospital must provide evaluation, service, and/or referral as indicated by the urgency of the case. When medically appropriate and legally permissible, or when a patient has so requested, a patient may be transferred to another facility. The institution to which the patient is to be transferred must first have accepted the patient for transfer. The patient must also have the benefit of complete information and explanation concerning the need for, risks, benefits, and alternatives to such a transfer. - The patient has the right to ask and be informed of the existence of business relationships among the hospital, educational institutions, other health care providers, or payers that may influence the patient’s treatment and care. - The patient has the right to consent to or decline to participate in proposed research studies or human experimentation affecting care and treatment or requiring direct patient involvement and to have those studies fully explained prior to consent. A patient who declines to participate in research or experimentation is entitled to the most effective care that the hospital can otherwise provide. - The patient has the right to expect reasonable continuity of care when appropriate and to be informed by physicians and other caregivers of available and realistic patient care options when hospital care is no longer appropriate. - The patient has the right to be informed of hospital policies and practices that relate to patient care, treatment, and responsibilities. The patient has the right to be informed of available resources for resolving disputes, grievances, and conflicts, such as ethics committees, patient representatives, or other mechanisms available in the institution. The patient has the right to be informed of the hospital’s charges for services and available payment methods. Read a current version of the “Patient Care Partnership” brochure from the American Hospital Association that has replaced the Patient’s Bill of Rights. 3.4 Cultural Competence Open Resources for Nursing (Open RN) The freedom to express one’s cultural beliefs is a fundamental right of all people. Nurses realize that people speak, behave, and act in many different ways due to the influential role that culture plays in their lives and their view of the world. Cultural competence is a lifelong process of applying evidence-based nursing in agreement with the cultural values, beliefs, worldview, and practices of patients to produce improved patient outcomes.Centers for Disease Control and Prevention. (2020, October 21). Cultural competence in health and human services. https://npin.cdc.gov/pages/cultural-competence,Curtis, E., Jones, R., Tipene-Leach, D., Walker, C., Loring, B., Paine, S.-J., & Reid, P. (2019). Why cultural safety rather than cultural competency is required to achieve health equity: A literature review and recommended definition. International Journal for Equity in Health, 18, 174. https://doi.org/10.1186/s12939-019-1082-3,Young, S., & Guo, K. (2016). Cultural diversity training: The necessity for cultural competence for healthcare providers and in nursing practice. The Health Care Manager, 35(2), 94-102. https://doi.org/10.1097/hcm.0000000000000100 Culturally-competent care requires nurses to combine their knowledge and skills with awareness, curiosity, and sensitivity about their patients’ cultural beliefs. It takes motivation, time, and practice to develop cultural competence, and it will evolve throughout your nursing career. Culturally competent nurses have the power to improve the quality of care leading to better health outcomes for culturally diverse patients. Nurses who accept and uphold the cultural values and beliefs of their patients are more likely to develop supportive and trusting relationships with their patients. In turn, this opens the way for optimal disease and injury prevention and leads towards positive health outcomes for all patients . The roots of providing culturally-competent care are based on the original transcultural nursing theory developed by Dr. Madeleine Leininger. Transcultural nursing incorporates cultural beliefs and practices of individuals to help them maintain and regain health or to face death in a meaningful way.Murphy, S. C. (2006). Mapping the literature of transcultural nursing. Journal of the Medical Library Association: JMLA, 94(2 Suppl), e143–e151. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1463039/ See Figure 3.4“Leininger.jpg” by Juda712 is licensed under CC BY-SA 3.0 for an image of Dr. Leininger. Read more about transcultural nursing theory in the following box. Madeleine Leininger and the Transcultural Nursing TheoryMurphy, S. C. (2006). Mapping the literature of transcultural nursing. Journal of the Medical Library Association: JMLA, 94(2 Suppl), e143–e151. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1463039/ Dr. Madeleine Leininger (1925-2012) founded the transcultural nursing theory. She was the first professional nurse to obtain a PhD in anthropology. She combined the “culture” concept from anthropology with the “care” concept from nursing and reformulated these concepts into “culture care.” In the mid-1950s, no cultural knowledge base existed to guide nursing decisions or understand cultural behaviors as a way of providing therapeutic care. Leininger wrote the first books in the field and coined the term “culturally congruent care.” She developed and taught the first transcultural nursing course in 1966, and master’s and doctoral programs in transcultural nursing were launched shortly after. Dr. Leininger was honored as a Living Legend of the American Academy of Nursing in 1998. Nurses have an ethical and moral obligation to provide culturally competent care to the patients they serve.Young, S., & Guo, K. (2016). Cultural diversity training: The necessity for cultural competence for healthcare providers and in nursing practice. The Health Care Manager, 35(2), 94-102. https://doi.org/10.1097/hcm.0000000000000100 The “Respectful and Equitable Practice” Standard of Professional Performance set by the American Nurses Association (ANA) states that nurses must practice with cultural humility and inclusiveness. The ANA Code of Ethics also states that the nurse should collaborate with other health professionals, as well as the public, to protect human rights, fight discriminatory practices, and reduce disparities.American Nurses Association. (2015). Code of ethics for nurses with interpretive statements. American Nurses Association. https://www.nursingworld.org/practice-policy/nursing-excellence/ethics/code-of-ethics-for-nurses/coe-view-only/ Additionally, the ANA Code of Ethics also states that nurses “are expected to be aware of their own cultural identifications in order to control their personal biases that may interfere with the therapeutic relationship. Self-awareness involves not only examining one’s culture but also examining perceptions and assumptions about the patient’s culture…nurses should possess knowledge and understanding how oppression, racism, discrimination, and stereotyping affect them personally and in their work.”American Nurses Association. (2015). Code of ethics for nurses with interpretive statements. American Nurses Association. https://www.nursingworld.org/practice-policy/nursing-excellence/ethics/code-of-ethics-for-nurses/coe-view-only/ Developing cultural competence begins in nursing school.Gillson, S., & Cherian, N. (2019). The importance of teaching cultural diversity in baccalaureate nursing education. Journal of Cultural Diversity, 26(3), 85–88.,Gavin-Knecht, J., Fontana, J. S., Fischer, B., Spitz, K. R., & Tetreault, J. N. (2018). An investigation of the development of cultural competence in baccalaureate nursing students: A mixed methods study. Journal of Cultural Diversity, 26(3), 89-95. Culture is an integral part of life, but its impact is often implicit. It is easy to assume that others share the same cultural values that you do, but each individual has their own beliefs, values, and preferences. Begin the examination of your own cultural beliefs and feelings by answering the questions below.Zeran, V. (2016). Cultural competency and safety in nursing education: A case study. Northern Review, 43, 105–115. https://thenorthernreview.ca/index.php/nr/article/view/591 Reflect on the following questions carefully and contemplate your responses as you begin your journey of providing culturally responsive care as a nurse. (Questions are adapted from the Anti Defamation League’s “Imagine a World Without Hate” Personal Self-Assessment Anti-Bias Behavior).Anti-Defamation League. (2013). Imagine a world without hate: Anti-Defamation League 2012 Annual Report. https://www.adl.org/media/4528/download. - Who are you? With what cultural group or subgroups do you identify? - When you meet someone from another culture/country/place, do you try to learn more about them? - Do you notice instances of bias, prejudice, discrimination, and stereotyping against people of other groups or cultures in your environment (home, school, work, TV programs or movies, restaurants, places where you shop)? - Have you reflected on your own upbringing and childhood to better understand your own implicit biases and the ways you have internalized messages you received? - Do you ever consider your use of language to avoid terms or phrases that may be degrading or hurtful to other groups? - When other people use biased language and behavior, do you feel comfortable speaking up and asking them to refrain? The Process of Developing Cultural Competence Dr. Josephine Campinha-Bacote is an influential nursing theorist and researcher who developed a model of cultural competence. The model asserts there are specific characteristics that a nurse becoming culturally competent possesses, including cultural awareness, cultural knowledge, cultural skill, and cultural encounters.Transcultural C.A.R.E. Associates. (2020). The Process of Cultural Competemility. http://transculturalcare.net/the-process-of-cultural-competence-in-the-delivery-of-healthcare-services/ Cultural awareness is a deliberate, cognitive process in which health care providers become appreciative and sensitive to the values, beliefs, attitudes, practices, and problem-solving strategies of a patient’s culture. To become culturally aware, the nurse must undergo reflective exploration of personal cultural values while also becoming conscious of the cultural practices of others. In addition to reflecting on one’s own cultural values, the culturally competent nurse seeks to reverse harmful prejudices, ethnocentric views, and attitudes they have. Cultural awareness goes beyond a simple awareness of the existence of other cultures and involves an interest, curiosity, and appreciation of other cultures. Although cultural diversity training is typically a requirement for health care professionals, cultural desire refers to the intrinsic motivation and commitment on the part of a nurse to develop cultural awareness and cultural competency.Anti-Defamation League. (2013). Imagine a world without hate: Anti-Defamation League 2012 Annual Report. https://www.adl.org/media/4528/download. Acquiring cultural knowledge is another important step towards becoming a culturally competent nurse. Cultural knowledge refers to seeking information about cultural health beliefs and values to understand patients’ world views. To acquire cultural knowledge, the nurse actively seeks information about other cultures, including common practices, beliefs, values, and customs, particularly for those cultures that are prevalent within the communities they serve.Gillson, S., & Cherian, N. (2019). The importance of teaching cultural diversity in baccalaureate nursing education. Journal of Cultural Diversity, 26(3), 85–88. Cultural knowledge also includes understanding the historical backgrounds of culturally diverse groups in society, as well as physiological variations and the incidence of certain health conditions in culturally diverse groups. Cultural knowledge is best obtained through cultural encounters with patients from diverse backgrounds to learn about individual variations that occur within cultural groups and to prevent stereotyping. While obtaining cultural knowledge, it is important to demonstrate cultural sensitivity. Cultural sensitivity means being tolerant and accepting of cultural practices and beliefs of people. Cultural sensitivity is demonstrated when the nurse conveys nonjudgmental interest and respect through words and action and an understanding that some health care treatments may conflict with a person’s cultural beliefs.Curtis, E., Jones, R., Tipene-Leach, D., Walker, C., Loring, B., Paine, S.-J., & Reid, P. (2019). Why cultural safety rather than cultural competency is required to achieve health equity: A literature review and recommended definition. International Journal for Equity in Health, 18, 174. https://doi.org/10.1186/s12939-019-1082-3 Cultural sensitivity also implies a consciousness of the damaging effects of stereotyping, prejudice, or biases on patients and their well-being. Nurses who fail to act with cultural sensitivity may be viewed as uncaring or inconsiderate, causing a breakdown in trust for the patient and their family members. When a patient experiences nursing care that contradicts with their cultural beliefs, they may experience moral or ethical conflict, nonadherence, or emotional distress. Cultural desire, awareness, sensitivity, and knowledge are the building blocks for developing cultural skill. Cultural skill is reflected by the nurse’s ability to gather and synthesize relevant cultural information about their patients while planning care and using culturally sensitive communication skills. Nurses with cultural skill provide care consistent with their patients’ cultural needs and deliberately take steps to secure a safe health care environment that is free of discrimination or intolerance. For example, a culturally skilled nurse will make space and seating available within a patient’s hospital room for accompanying family members when this support is valued by the patient.Brooks, L., Manias, E., & Bloomer, M. (2019). Culturally sensitive communication in healthcare: A concept analysis. Collegian, 26(3), 383-391. https://doi.org/10.1016/j.colegn.2018.09.007 Cultural encounters is a process where the nurse directly engages in face-to-face cultural interactions and other types of encounters with clients from culturally diverse backgrounds in order to modify existing beliefs about a cultural group and to prevent possible stereotyping. By developing the characteristics of cultural awareness, cultural knowledge, cultural skill, and cultural encounters, a nurse develops cultural competence. 3.5 Health Disparities Open Resources for Nursing (Open RN) Despite decades of promoting cultural competent care and the Patient’s Bill of Rights, disparities in health care continue. Vulnerable populations continue to experience increased prevalence and burden of diseases, as well as problems accessing quality health care. In 2003 the Institute of Medicine (IOM) published Unequal Treatment: Confronting Racial and Ethnic Disparities in Health Care, sharing evidence that “bias, prejudice, and stereotyping on the part of health care providers may contribute to differences in care.”Institute of Medicine (US) Committee on Understanding and Eliminating Racial and Ethnic Disparities in Health Care, Smedley, B. D., Stith, A. Y., Nelson, A. R. (Eds.). (2003). Unequal treatment: Confronting racial and ethnic disparities in health care. National Academies Press. https://doi.org/10.17226/12875 The health care system in the United States was shaped by the values and beliefs of mainstream white culture and originally designed to primarily serve English-speaking patients with financial resources.Meedzan, N. (2015). Cultural immersion experiences in nursing education. In S. Breakey, I. Corless, N. Meedzan, & P. Nicholas (Eds.) Global nursing in the 21st century. Springer. pp. 441-452. In addition, most health care professionals in the United States are members of the white culture and medical treatments tend to arise from that perspective.Hart, P. L., & Mareno, N. (2016). Nurses’ perceptions of their cultural competence in caring for diverse patient populations. Online Journal of Cultural Competence in Nursing & Healthcare, 6(1), 121–137. https://doi.org/10.9730/ojccnh.org/v6n1a10,Ong-Flaherty, C. (2015). Critical cultural awareness and diversity in nursing: A minority perspective. Nurse Leader, 13(5), 58-62. http://dx.doi.org/10.1016/j.mnl.2015.03.012 The term health disparities describes the differences in health outcomes that result from social determinants of health. Social determinants of health are conditions in the environment where people are born, live, learn, work, play, worship, and age that affect a wide range of health, functioning, and quality-of-life outcomes. Resources that enhance quality of life can have a significant influence on population health outcomes. Examples of resources include safe and affordable housing, access to education, public safety, availability of healthy foods, local emergency/health services, and environments free of life-threatening toxins.Healthy People 2020. (2020). Social Determinants of Health. https://www.healthypeople.gov/2020/topics-objectives/topic/social-determinants-of-health Vulnerable populations experience increased prevalence and burden of diseases, as well as problems accessing quality health care because of social determinants of health. Healthy People 2020. Lesbian, gay, bisexual, and transgender health. https://www.healthypeople.gov/2020/topics-objectives/topic/lesbian-gay-bisexual-and-transgender-health A related term is health care disparity that refers to differences in access to health care and insurance coverage. Health disparities and health care disparities can lead to decreased quality of life, increased personal costs, and lower life expectancy. More broadly, these disparities also translate to greater societal costs, such as the financial burden of uncontrolled chronic illnesses. The Agency for Healthcare Research and Quality (AHRQ) releases an annual National Healthcare Quality and Disparities Report that provides a comprehensive overview of the quality of health care received by the general U.S. population and disparities in care experienced by different racial and socioeconomic groups. Quality is described in terms of patient safety, person-centered care, care coordination, effective treatment, healthy living, and care affordability.Agency for Healthcare Research and Quality. (2020). 2019 National healthcare quality and disparities report. https://www.ahrq.gov/research/findings/nhqrdr/nhqdr19/index.html Although access to health care and quality have improved since 2000 in the wake of the Affordable Care Act (ACA), the 2019 report shows continued disparities, especially for poor and uninsured populations: - For about 40% of quality measures, Blacks, African Americans, and Alaska Natives received worse care than Whites. For more than one third of quality measures, Hispanics received worse care than Whites. - For nearly a quarter of quality measures, residents of large metropolitan areas received worse care than residents of suburban areas. For one third of quality measures, residents of rural areas received worse care than residents of suburban areas.Agency for Healthcare Research and Quality. (2020). 2019 National healthcare quality and disparities report. https://www.ahrq.gov/research/findings/nhqrdr/nhqdr19/index.html There are several initiatives and agencies designed to combat the problem of health disparities in the United States. See Table 3.5 for a list of hyperlinks to available resources to combat health disparities. Table 3.5 Resources to Combat Health Disparities \| AHRQ publishes the National Healthcare Quality and Disparities Report, a report on measures related to access to care, affordable care, care coordination, effective treatment, healthy living, patient safety, and person-centered care. \| \| \| A new Healthy People initiative is launched every ten years. The initiative guides national health promotion and disease prevention efforts to improve the health of the nation. \| \| \| The mission of the Office of Minority Health is to improve the health of minority populations and to act as a resource for health care providers. The Office of Minority Health has published National Standards for Culturally and Linguistically Appropriate Services in Health and Health Care (CLAS). \| \| \| Racial and Ethnic Approaches to Community Health Across the United States (REACH-US) \| This initiative, overseen by the Centers for Disease Control (CDC), seeks to remove barriers to health linked to race or ethnicity, education, income, location, or other social factors. \| \| National Partnership for Action to End Health Disparities (NPA) \| The mission of the NPA is to raise awareness and increase the effectiveness of programs targeting health disparities. \| \| RWJF is a philanthropic organization with the goal of identifying the root causes of health disparities and removing barriers to improve health outcomes. \| \| \| The nonprofit Sullivan Alliance was formed to increase the numbers of ethnic and racial minorities within the health professions to raise awareness about health disparities and to develop partnerships between academia and the health professions. \| \| \| Transcultural Nursing Society – Many Cultures One World (TCNS) \| The mission of TCNS is to improve the quality of culturally congruent and equitable care for people worldwide by ensuring cultural competence in nursing practice, scholarship, education, research, and administration. \| See the following box for an example of nurses addressing a community health care disparity during the water crisis in Flint, Michigan. Nurses Addressing the Flint Michigan Water CrisisHouseholder, M. (2016, April 12). Health workers get lead-test help from Flint student nurses. Associated Press. https://detroit.cbslocal.com/2016/04/12/health-workers-get-lead-test-help-from-flint-student-nurses/. In 2014 the water system in Flint, Michigan, was discovered to be contaminated with lead. The city’s children were found to have perilously elevated lead levels. Children from poor households were most affected by the crisis. Lead is a dangerous neurotoxin. Elevated lead levels are linked to slowed physical development; low IQ; problems with cognition, attention, and memory; and learning disabilities. In Flint approximately 150 local nurses and nursing students answered the call, organizing and arranging educational seminars, as well as setting up lead testing clinics to determine who had been affected by the water contamination. A nursing student involved in the effort told CBS Detroit that this situation has illustrated that “the need for health care, the need for nursing, goes way outside the hospital walls.” See Figure 3.5“Flint_Water_Crisis.jpg” by Shannon Nobles is licensed under CC BY-SA 4.0 for an image of the water crisis in Flint, Michigan. Reflective Questions - What factors led to the children from poor households being so adversely harmed by this crisis? - What are ways that you as a future nurse can make a difference for vulnerable or marginalized people? Providing culturally responsive care is a key strategy for reducing health disparities.Zeran, V. (2016). Cultural competency and safety in nursing education: A case study. Northern Review, 43, 105–115. https://thenorthernreview.ca/index.php/nr/article/view/591 While there are multiple determinants contributing to a person’s health, nurses play an important role in reducing health disparities by providing a culturally sensitive environment, performing a cultural assessment, and providing culturally responsive care. These interventions will be further discussed in the following sections. On the other hand, a lack of culturally responsive care potentially contributes to miscommunication between the patient and the nurse. The patient may experience distress or loss of trust in the nurse or the health care system as a whole and may not adhere to prescribed treatments. Nurses are uniquely positioned to directly impact patient outcomes as we become more aware of unacceptable health disparities and work together to overcome them.Colorado Nurses Foundation and Colorado Nurses Association. (2020). Owning our biases: How nursing can change the healthcare landscape. Colorado Nurse, 120(3). https://assets.nursingald.com/uploads/publication/pdf/2103/Colorado_Nurse_8_20.pdf 3.6 Culturally Sensitive Care Open Resources for Nursing (Open RN) Providing culturally responsive care integrates an individual’s cultural beliefs into their health care. Begin by conveying cultural sensitivity to patients and their family members with these suggestions:Brooks, L., Manias, E., & Bloomer, M. (2019). Culturally sensitive communication in healthcare: A concept analysis. Collegian, 26(3), 383-391. https://doi.org/10.1016/j.colegn.2018.09.007 - Set the stage by introducing yourself by name and role when meeting the patient and their family for the first time. Until you know differently, address the patient formally by using their title and last name. Ask the patient how they wish to be addressed and record this in the patient’s chart. Respectfully acknowledge any family members and visitors at the patient’s bedside. - Begin by standing or sitting at least arm’s length from the patient. - Observe the patient and family members in regards to eye contact, space orientation, touch, and other nonverbal communication behaviors and follow their lead. - Make note of the language the patient prefers to use and record this in the patient’s chart. If English is not the patient’s primary language, determine if a medical interpreter is required before proceeding with interview questions. See the box below for guidelines in using a medical interpreter. - Use inclusive language that is culturally sensitive and appropriate. For example, do not refer to someone as “wheelchair bound”; instead say “a person who uses a wheelchair.” UK Office for Disability Issues. (2018, December 13). Inclusive language: Words to use and avoid when writing about disability. https://www.gov.uk/government/publications/inclusive-communication/inclusive-language-words-to-use-and-avoid-when-writing-about-disability. - Be open and honest about the extent of your knowledge of their culture. It is acceptable to politely ask questions about their beliefs and seek clarification to avoid misunderstandings. - Adopt a nonjudgmental approach and show respect for the patient’s cultural beliefs, values, and practices. It is possible that you may not agree with a patient’s cultural expressions, but it is imperative that the patient’s rights are upheld. As long as the expressions are not unsafe for the patient or others, the nurse should attempt to integrate them into their care. Guidelines for Using a Medical InterpreterJuckett, G., & Unger, K. (2014). Appropriate use of medical interpreters. American Family Physician, 90(7), 476-80. https://pubmed.ncbi.nlm.nih.gov/25369625/ When caring for a patient whose primary language is not English and they have a limited ability to speak, read, write, or understand the English language, seek the services of a trained medical interpreter. Health care facilities are mandated by The Joint Commission to provide qualified medical interpreters. Use of a trained medical interpreter is linked to fewer communication errors, shorter hospital stays, reduced 30-day readmission rates, and improved patient satisfaction. Refrain from asking a family member to act as an interpreter. The patient may withhold sensitive information from them, or family members may possibly edit or change the information provided. Unfamiliarity with medical terminology can also cause misunderstanding and errors. Medical interpreters may be on-site or available by videoconferencing or telephone. The nurse should also consider coordinating patient and family member conversations with other health care team members to streamline communication, while being aware of cultural implications such who can discuss what health care topics and who makes the decisions. When possible, obtain a medical interpreter of the same gender as the patient to prevent potential embarrassment if a sensitive matter is being discussed. Guidelines for working with a medical interpreter: - Allow extra time for the interview or conversation with the patient. - Whenever possible, meet with the interpreter beforehand to provide background. - Document the name of the medical interpreter in the progress note. - Always face and address the patient directly, using a normal tone of voice. Do not direct questions or conversation to the interpreter. - Speak in the first person (using “I”). - Avoid using idioms, such as, “Are you feeling under the weather today?” Avoid abbreviations, slang, jokes, and jargon. - Speak in short paragraphs or sentences. Ask only one question at a time. Allow sufficient time for the interpreter to finish interpreting before beginning another statement or topic. - Ask the patient to repeat any instructions and explanations given to verify that they understood. 3.7 Cultural Assessment Open Resources for Nursing (Open RN) After establishing a culturally sensitive environment, nurses should incorporate a cultural assessment when caring for all patients. There are many assessment guides used for patient interviews that are adaptable to a variety of health care settings and are designed to facilitate understanding and communication. The Four Cs of Culture modelGalanti, G. A. (2014). Caring for patients from different cultures (5th ed.). University of Pennsylvania Press. is an example of a quick cultural assessment tool that asks questions about what the patient Considers to be a problem, the Cause of the problem, how they are Coping with the problem, and how Concerned they are about the problem. See the following box for examples of sample answers to the four Cs assessment. Four Cs of CultureGalanti, G. A. (2014). Caring for patients from different cultures (5th ed.). University of Pennsylvania Press. 1. What do you think is wrong? What is worrying you? (In other words, discover what the patient Considers to be the problem and what they Call it.) - A patient with a diagnosis of pneumonia believes his body is “unbalanced.” 2. What do you think Caused this problem? How did this happen? - The patient believes this illness is a punishment for a misdeed. - The patient avoids eating certain foods to treat the illness while also using home remedies such as herbal tea. 3. How serious is this problem for you? How Concerned are you? - A patient views the illness as being “God’s will” and states, “It’s in God’s hands.” A more comprehensive cultural assessment tool, inspired by R. E. Spector’s Heritage Assessment interview,Spector, R. E. (2017). Cultural diversity in health and illness (9th ed.). Pearson Education. is described in the following box. Sample Cultural Assessment Interview (Adapted from Spector’s Heritage Assessment Tool)Spector, R. E. (2017). Cultural diversity in health and illness (9th ed.). Pearson Education. - Where were you born? Where were your parents born? - What pronoun do you use (he, she, they)? - In what language are you most comfortable speaking and reading? - Did you grow up in a city or a town or a rural setting? - When you were growing up, who lived with you and your family? - Are your friends from the same cultural background as you? - What is your religious preference? - Do you have any dietary preferences related to your religious or cultural beliefs? - In your culture, how do you celebrate the birth of a baby? A wedding? - When a woman is pregnant, are there any special customs she needs to follow? Any special foods? - When someone in your family is ill, who cares for them? What foods are prepared? Is there anything the ill person should avoid or refrain from doing? - What home remedies might be used if someone is ill? - As a family member is approaching death, what actions do you find comforting? - After a loved one dies, what rituals are performed? - What do you think a nurse should know about your culture if a family member is hospitalized? - Who makes the decisions in your family? - How are elders viewed in your culture? - Are there any special beliefs regarding organ donation or blood transfusions that are held in your culture? - Is your culture known for any special customs (e.g., rites of passage, foods, holidays, etc.)? 3.8 Culturally Responsive Care Open Resources for Nursing (Open RN) After establishing a culturally sensitive environment and performing a cultural assessment, nurses and nursing students can continue to promote culturally responsive care. Culturally responsive care includes creating a culturally safe environment, using cultural negotiation, and considering the impact of culture on patients’ time orientation, space orientation, eye contact, and food choices. Culturally Safe Environment A primary responsibility of the nurse is to ensure the environment is culturally safe for the patient. A culturally safe environment is a safe space for patients to interact with the nurse, without judgment or discrimination, where the patient is free to express their cultural beliefs, values, and identity. This responsibility belongs to both the individual nurse and also to the larger health care organization. Cultural Negotiation Many aspects of nursing care are influenced by the patient’s cultural beliefs, as well as the beliefs of the health care culture. For example, the health care culture in the United States places great importance on punctuality for medical appointments, yet a patient may belong to a culture that views “being on time” as relative. In some cultures, time is determined simply by whether it is day or night or time to wake up, eat, or sleep. Making allowances or accommodations for these aspects of a patient’s culture is instrumental in fostering the nurse-patient relationship. This accommodation is referred to as cultural negotiation. See Figure 3.6“handshake-3378251_1920.jpg” by geralt is licensed under CC0 for an image illustrating cultural negotiation. During cultural negotiation, both the patient and nurse seek a mutually acceptable way to deal with competing interests of nursing care, prescribed medical care, and the patient’s cultural needs. Cultural negotiation is reciprocal and collaborative. When a patient’s cultural needs do not significantly or adversely affect their treatment plan, their cultural needs should be accommodated when feasible. As an example, think about the previous example of a patient for whom a fixed schedule is at odds with their cultural views. Instead of teaching the patient to take a daily medication at a scheduled time, the nurse could explain that the patient should take the medication every day when he gets up. Another example of cultural negotiation is illustrated by a scenario in which the nurse is preparing a patient for a surgical procedure. As the nurse goes over the preoperative checklist, the nurse asks the patient to remove her head covering (hijab). The nurse is aware that personal items should be removed before surgery; however, the patient wishes to keep on the hijab. As an act of cultural negotiation and respect for the patient’s cultural beliefs, the nurse makes arrangements with the surgical team to keep the patient’s hijab in place for the surgical procedure and covering the patient’s hijab with a surgical cap. Decision-Making Health care culture in the United States mirrors cultural norms of the country, with an emphasis on individuality, personal freedom, and self-determination. This perspective may conflict with a patient whose cultural background values group decision-making and decisions made to benefit the group, not necessarily the individual. As an example, in the 2019 film The Farewell, a Chinese-American family decides to not tell the family matriarch she is dying of cancer and only has a few months left to live. The family keeps this secret from the woman in the belief that the family should bear the emotional burden of this knowledge, which is a collectivistic viewpoint in contrast to American individualistic viewpoint. Space Orientation The amount of space that a person surrounds themselves with to feel comfortable is influenced by culture. (Read more about space orientation in the “Communication” chapter.) See Figure 3.7“Proxemics.png” by Natbrock Alicia Tom is licensed under CC BY-SA 3.0 for an image illustrating space orientation. For example, for some people, it would feel awkward to stand four inches away from another person while holding a social conversation, but for others a small personal space is expected when conversing with another.Kreuz, R., & Roberts, R. (2019). Proxemics 101: Understanding personal space across cultures. The MITPress Reader. https://thereader.mitpress.mit.edu/understanding-personal-space-proxemics/There are times when a nurse must enter a patient’s intimate or personal space, which can cause emotional distress for some patients. The nurse should always ask for permission before entering a patient’s personal space and explain why and what is about to happen. Patients may also be concerned about their modesty or being exposed. A patient may deal with the violation of their space by removing themselves from the situation, pulling away, or closing their eyes. The nurse should recognize these cues for what they are, an expression of cultural preference, and allow the patient to assume a position or distance that is comfortable for them. Similar to cultural influences on personal space, touch is also culturally determined. This has implications for nurses because it may be inappropriate for a male nurse to provide care for a female patient and vice versa. In some cultures, it is also considered rude to touch a person’s head without permission. Eye Contact Eye contact is also a culturally mediated behavior. See Figure 3.8“271509.png” by amcolley is in the Public Domain for an image of eye contact. In the United States, direct eye contact is valued when communicating with others, but in some cultures, direct eye contact is interpreted as being rude or bold. Rather than making direct eye contact, a patient may avert their eyes or look down at the floor to show deference and respect to the person who is speaking. The nurse should notice these cultural cues from the patient and mirror the patient’s behaviors when possible. Food Choices Culture plays a meaningful role in the dietary practices and food choices of many people. Food is used to celebrate life events and holidays. Most cultures have staple foods, such as bread, pasta, or rice and particular ways of preparing foods. See Figure 3.9“wanna-cuppa-singapore-cafe-food-bistro-trees-dishes-craft-beer-ale-breakfast-lunch-dinner-dark-1920×1080.jpg” by Jennette Kwok is licensed under CC BY-NC-SA 4.0 for an image of various food choices. Special foods are prepared to heal and to cure or to demonstrate kinship, caring, and love. For example, in the United States, chicken noodle soup is often prepared and provided to family members who are ill. Conversely, certain foods and beverages (such as meat and alcohol) are forbidden in some cultures. Nurses should accommodate or negotiate dietary requests of their patients, knowing that food holds such an important meaning to many people. Summary In summary, there are several steps in the journey of becoming a culturally competent nurse with cultural humility who provides culturally responsive care to patients. As you continue in your journey of developing cultural competency, keep the summarized points in the following box in mind. Summary of Developing Cultural Competency - Cultural competence is an ongoing process for nurses and takes dedication, time, and practice to develop. - Pursuing the goal of cultural competence in nursing and other health care disciplines is a key strategy in reducing health care disparities. - Culturally competent nurses recognize that culture functions as a source of values and comfort for patients, their families, and communities. - Culturally competent nurses intentionally provide patient-centered care with sensitivity and respect for culturally diverse populations. - Misunderstandings, prejudices, and biases on the part of the health care provider interfere with the patient’s health outcomes. - Culturally competent nurses negotiate care with a patient so that is congruent with the patient’s cultural beliefs and values. - Nurses should examine their own biases, ethnocentric views, and prejudices so as not to interfere with the patient’s care. - Nurses who respect and understand the cultural values and beliefs of their patients are more likely to develop positive, trusting relationships with their patients. 3.9 Putting It All Together Patient Scenario Mrs. Rosas is a 76-year-old patient admitted to the cardiology floor with an exacerbation of congestive heart failure. The patient’s primary language is Spanish, and she has a limited understanding of English. The patient’s daughter reports that the patient has been experiencing increased swelling in her ankles and increased shortness of breath over the last three weeks. Her daughter also reports that the patient has noted unexplained weight gain. During the admission assessment the nurse attempts to collect additional information related to current symptoms, diet, and history. The patient nods in response to questions and converses quietly in Spanish with her daughter. Applying the Nursing Process Assessment: The nurse notes that the patient does not respond to questions appropriately and is unable to converse in English. She defers to her daughter to provide interpretation of questions and relay information. Based on the assessment information that has been gathered, the following nursing care plan is created for Mrs. Rosas. Nursing Diagnosis: Impaired Verbal Communication related to cultural incongruence as evidenced by inability to speak the language of the caregiver. Overall Goal: The patient will use effective communication techniques. SMART Expected Outcome: Mrs. Rosas will utilize interpreter services in order to receive information and express needs throughout her hospitalization. Planning and Implementing Nursing Interventions: The nurse will provide patient with interpreter services in order to facilitate patient communication. In-person interpreter or language line telephone services will be utilized to ensure that the patient receives information about her care. The nurse will eliminate distractions such as the television, hallway noise, etc., to decrease sources of additional stimuli in the communication experience. The nurse will communicate directly with the patient, utilizing appropriate eye contact, and nonverbal cues to enhance the communication experience. Sample Documentation Mrs. Rosas has impaired verbal communication due to limited English proficiency. She requires education regarding cardiac diet, fluid restriction, and exacerbation warning signs. Interpreter services have been utilized to ensure that communication and education needs are appropriate. Mrs. Rosas communicates freely through the interpreter and acknowledges understanding of the education that has been provided. Evaluation During the patient’s hospitalization, Mrs. Rosas engages with staff through the use of interpreter services and actively participates in her own care. 3.10 Learning Activities Open Resources for Nursing (Open RN) Learning Activities (Answers to “Learning Activities” can be found in the “Answer Key” at the end of the book. Answers to interactive activity elements will be provided within the element as immediate feedback.) 1. Test yourself for implicit bias at the Learning for Justice website. 2. Consider the following scenario. You are completing the admission assessment for Mr. Xiong, a 64-year-old patient admitted to the medical surgical floor with acute kidney injury. Mr. Xiong speaks Hmong and some English. What actions should be undertaken to ensure that you are providing culturally responsive care to Mr. Xiong? An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=433#h5p-89 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=433#h5p-83 3.11 Supplementary Videos Open Resources for Nursing (Open RN) View these supplementary videos regarding cultural diversity and cultural competence: Haley Yeates \| It’s Past Time to Appreciate Cultural DiversityTED Institute. (2018, February 15). It’s (past) time to appreciate cultural diversity \| Hayley Yeates \| TED Institute. [Video]. YouTube. Video licensed under CC BY–NC–ND 4.0. Becoming a Culturally Competent NurseJohnson & Johnson Nursing. (2018, December 3). Becoming a culturally competent nurse. [Video]. YouTube. All rights reserved. https://www.youtube.com/watch?v=r62Zp99U67Y&feature=emb_title III Glossary Open Resources for Nursing (Open RN) Assimilation: The process of adopting or conforming to the practices, habits, and norms of a cultural group. As a result, the person gradually takes on a new cultural identity and may lose their original identity in the process. Bias: To carry an attitude, opinion, or inclination (positive or negative) towards a group or members of a group. Bias can be a conscious attitude (explicit), or a person may not be aware of their bias (implicit). Cultural awareness: A deliberate, cognitive process in which health care providers become appreciative and sensitive to the values, beliefs, lifeways, practices, and problem-solving strategies of a patient’s culture. Cultural awareness goes beyond a simple awareness of the existence of other cultures and involves an interest, curiosity, and appreciation of other cultures. Cultural competency: The process of applying evidence-based nursing in agreement with the preferred cultural values, beliefs, worldview, and practices of patients to produce improved patient outcomes. Cultural diversity: Cultural differences in people. Cultural encounters: A process where the nurse directly engages in face-to-face cultural interactions and other types of encounters with clients from culturally diverse backgrounds in order to modify existing beliefs about a cultural group and to prevent possible stereotyping. Cultural humility: A humble and respectful attitude toward individuals of other cultures that pushes one to challenge their own cultural biases, realize they cannot know everything about other cultures, and approach learning about other cultures as a lifelong goal and process.American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. Cultural negotiation: A process where the patient and nurse seek a mutually acceptable way to deal with competing interests of nursing care, prescribed medical care, and the patient’s cultural needs. Cultural negotiation is reciprocal and collaborative. When the patient’s cultural needs do not significantly or adversely affect their treatment plan, the cultural needs can be accommodated. Culturally responsive care: Nursing actions that integrate a person’s cultural beliefs into their care. Culturally safe environment: A safe space for patients to interact with health professionals, without judgment or discrimination, where the patient is free to express their cultural beliefs, values, and identity. Culture: A set of beliefs, attitudes, and practices shared by a group of people or community that is accepted, followed, and passed down to other members of the group. Discrimination: Unfair and different treatment of another person or group, denying them opportunities and rights to participate fully in society. Ethnocentrism: The belief that one’s culture (or race, ethnicity, or country) is better and preferable than another’s. Gender expression: A person’s outward demonstration of gender in relation to societal norms, such as in style of dress, hairstyle, or other mannerisms. Gender identity: A person’s inner sensibility that they are a man, a woman, or perhaps neither. Health disparities: Differences in health outcomes resulting from entrenched economic, sociopolitical, or environmental disadvantages. Health care disparities: Differences in access to health care and insurance coverage. Holism: Treatment of the whole person, including physical, mental, spiritual, and social needs. Intersectionality: The many ways in which a person expresses their cultural identity are not separated, but are closely intertwined. Justice: A principle and moral obligation to act on the basis of equality and equity; a standard linked to fairness for all in society.American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. Prejudice: To “prejudge”; a preconceived idea, often unfavorable, about a person or group of people. Race: A socially constructed idea; there are no truly genetically or biologically distinct races. Humans are biologically similar to each other, not different. Racism: The presumption that races are distinct from one another and there is a hierarchy to race, implying that races are unequal. In racism, expression of one’s cultural beliefs is viewed as a heritable trait. Sexual orientation: A person’s physical and emotional interest or desire for others. Sexual orientation is on a continuum and is manifested in one’s self-identity and behaviors. Social determinants of health: Nonmedical factors that influence health outcomes, including conditions in which people are born, grow, work, live, and age, and the wider sets of forces and systems shaping the conditions of daily life.American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. Social justice: Equal rights, equal treatment, and equitable opportunities for all.American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. Stereotyping: Assuming that a person has the attributes, traits, beliefs, and values of a group because they are a member of that group. Subculture: A smaller group of people within a larger culture, often based on a person’s occupation, hobbies, interests, or place of origin. Transcultural nursing: Incorporating cultural beliefs and practices of people to help them maintain and regain health or to face death in a meaningful way. Nursing Process IV 4.1 Nursing Process Introduction Open Resources for Nursing (Open RN) Learning Objectives - Use the nursing process to provide patient care - Identify nursing diagnoses from evidence-based sources - Describe the development of a care plan - Prioritize patient care - Describe documentation for each step of the nursing process - Differentiate between the role of the PN and RN Have you ever wondered how a nurse can receive a quick handoff report from another nurse and immediately begin providing care for a patient they previously knew nothing about? How do they know what to do? How do they prioritize and make a plan? Nurses do this activity every shift. They know how to find pertinent information and use the nursing process as a critical thinking model to guide patient care. The nursing process becomes a road map for the actions and interventions that nurses implement to optimize their patients’ well-being and health. This chapter will explain how to use the nursing process as standards of professional nursing practice to provide safe, patient-centered care. 4.2 Basic Concepts Open Resources for Nursing (Open RN) Before learning how to use the nursing process, it is important to understand some basic concepts related to critical thinking and nursing practice. Let’s take a deeper look at how nurses think. Critical Thinking and Clinical Reasoning Nurses make decisions while providing patient care by using critical thinking and clinical reasoning. Critical thinking is a broad term used in nursing that includes “reasoning about clinical issues such as teamwork, collaboration, and streamlining workflow.”Klenke-Borgmann, L., Cantrell, M. A., & Mariani, B. (2020). Nurse educator’s guide to clinical judgment: A review of conceptualization, measurement, and development. Nursing Education Perspectives, 41(4), 215-221. Using critical thinking means that nurses take extra steps to maintain patient safety and don’t just “follow orders.” It also means the accuracy of patient information is validated and plans for caring for patients are based on their needs, current clinical practice, and research. “Critical thinkers” possess certain attitudes that foster rational thinking. These attitudes are as follows: - Independence of thought: Thinking on your own - Fair-mindedness: Treating every viewpoint in an unbiased, unprejudiced way - Insight into egocentricity and sociocentricity: Thinking of the greater good and not just thinking of yourself. Knowing when you are thinking of yourself (egocentricity) and when you are thinking or acting for the greater good (sociocentricity) - Intellectual humility: Recognizing your intellectual limitations and abilities - Nonjudgmental: Using professional ethical standards and not basing your judgments on your own personal or moral standards - Integrity: Being honest and demonstrating strong moral principles - Perseverance: Persisting in doing something despite it being difficult - Confidence: Believing in yourself to complete a task or activity - Interest in exploring thoughts and feelings: Wanting to explore different ways of knowing - Curiosity: Asking “why” and wanting to know more Clinical reasoning is defined as, “A complex cognitive process that uses formal and informal thinking strategies to gather and analyze patient information, evaluate the significance of this information, and weigh alternative actions.”Klenke-Borgmann, L., Cantrell, M. A., & Mariani, B. (2020). Nurse educator’s guide to clinical judgment: A review of conceptualization, measurement, and development. Nursing Education Perspectives, 41(4), 215-221. To make sound judgments about patient care, nurses must generate alternatives, weigh them against the evidence, and choose the best course of action. The ability to clinically reason develops over time and is based on knowledge and experience.Powers, L., Pagel, J., & Herron, E. (2020). Nurse preceptors and new graduate success. American Nurse Journal, 15(7), 37-39. Inductive and Deductive Reasoning and Clinical Judgment Inductive and deductive reasoning are important critical thinking skills. They help the nurse use clinical judgment when implementing the nursing process. Inductive reasoning involves noticing cues, making generalizations, and creating hypotheses. Cues are data that fall outside of expected findings that give the nurse a hint or indication of a patient’s potential problem or condition. The nurse organizes these cues into patterns and creates a generalization. A generalization is a judgment formed from a set of facts, cues, and observations and is similar to gathering pieces of a jigsaw puzzle into patterns until the whole picture becomes more clear. Based on generalizations created from patterns of data, the nurse creates a hypothesis regarding a patient problem. A hypothesis is a proposed explanation for a situation. It attempts to explain the “why” behind the problem that is occurring. If a “why” is identified, then a solution can begin to be explored. No one can draw conclusions without first noticing cues. Paying close attention to a patient, the environment, and interactions with family members is critical for inductive reasoning. As you work to improve your inductive reasoning, begin by first noticing details about the things around you. A nurse is similar to the detective looking for cues in Figure 4.1.“The Detective” by paurian is licensed under CC BY 2.0 Be mindful of your five primary senses: the things that you hear, feel, smell, taste, and see. Nurses need strong inductive reasoning patterns and be able to take action quickly, especially in emergency situations. They can see how certain objects or events form a pattern (i.e., generalization) that indicates a common problem (i.e., hypothesis). Example: A nurse assesses a patient and finds the surgical incision site is red, warm, and tender to the touch. The nurse recognizes these cues form a pattern of signs of infection and creates a hypothesis that the incision has become infected. The provider is notified of the patient’s change in condition, and a new prescription is received for an antibiotic. This is an example of the use of inductive reasoning in nursing practice. Deductive reasoning is another type of critical thinking that is referred to as “top-down thinking.” Deductive reasoning relies on using a general standard or rule to create a strategy. Nurses use standards set by their state’s Nurse Practice Act, federal regulations, the American Nursing Association, professional organizations, and their employer to make decisions about patient care and solve problems. Example: Based on research findings, hospital leaders determine patients recover more quickly if they receive adequate rest. The hospital creates a policy for quiet zones at night by initiating no overhead paging, promoting low-speaking voices by staff, and reducing lighting in the hallways. (See Figure 4.2).“In the Quiet Zone…” by C.O.D. Library is licensed under CC BY-NC-SA 2.0 The nurse further implements this policy by organizing care for patients that promotes periods of uninterrupted rest at night. This is an example of deductive thinking because the intervention is applied to all patients regardless if they have difficulty sleeping or not. Clinical judgment is the result of critical thinking and clinical reasoning using inductive and deductive reasoning. Clinical judgment is defined by the National Council of State Boards of Nursing (NCSBN) as, “The observed outcome of critical thinking and decision-making. It uses nursing knowledge to observe and assess presenting situations, identify a prioritized patient concern, and generate the best possible evidence-based solutions in order to deliver safe patient care.” NCSBN. (n.d.). NCSBN clinical judgment model. https://www.ncsbn.org/14798.htm The NCSBN administers the national licensure exam (NCLEX) that measures nursing clinical judgment and decision-making ability of prospective entry-level nurses to assure safe and competent nursing care by licensed nurses. Evidence-based practice (EBP) is defined by the American Nurses Association (ANA) as, “A lifelong problem-solving approach that integrates the best evidence from well-designed research studies and evidence-based theories; clinical expertise and evidence from assessment of the health care consumer’s history and condition, as well as health care resources; and patient, family, group, community, and population preferences and values.”American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. Nursing Process The nursing process is a critical thinking model based on a systematic approach to patient-centered care. Nurses use the nursing process to perform clinical reasoning and make clinical judgments when providing patient care. The nursing process is based on the Standards of Professional Nursing Practice established by the American Nurses Association (ANA). These standards are authoritative statements of the actions and behaviors that all registered nurses, regardless of role, population, specialty, and setting, are expected to perform competently.American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. The mnemonic ADOPIE is an easy way to remember the ANA Standards and the nursing process. Each letter refers to the six components of the nursing process: Assessment, Diagnosis, Outcomes Identification, Planning, Implementation, and Evaluation. The nursing process is a continuous, cyclic process that is constantly adapting to the patient’s current health status. See Figure 4.3“The Nursing Process” by Kim Ernstmeyer at Chippewa Valley Technical College is licensed under CC BY 4.0 for an illustration of the nursing process. Review Scenario A in the following box for an example of a nurse using the nursing process while providing patient care. Patient Scenario A: Using the Nursing Process“Patient Image in LTC.JPG” by ARISE project is licensed under CC BY 4.0 A hospitalized patient has a prescription to receive Lasix 80mg IV every morning for a medical diagnosis of heart failure. During the morning assessment, the nurse notes that the patient has a blood pressure of 98/60, heart rate of 100, respirations of 18, and a temperature of 98.7F. The nurse reviews the medical record for the patient’s vital signs baseline and observes the blood pressure trend is around 110/70 and the heart rate in the 80s. The nurse recognizes these cues form a pattern related to fluid imbalance and hypothesizes that the patient may be dehydrated. The nurse gathers additional information and notes the patient’s weight has decreased 4 pounds since yesterday. The nurse talks with the patient and validates the hypothesis when the patient reports that their mouth feels like cotton and they feel light-headed. By using critical thinking and clinical judgment, the nurse diagnoses the patient with the nursing diagnosis Fluid Volume Deficit and establishes outcomes for reestablishing fluid balance. The nurse withholds the administration of IV Lasix and contacts the health care provider to discuss the patient’s current fluid status. After contacting the provider, the nurse initiates additional nursing interventions to promote oral intake and closely monitor hydration status. By the end of the shift, the nurse evaluates the patient status and determines that fluid balance has been restored. In Scenario A, the nurse is using clinical judgment and not just “following orders” to administer the Lasix as scheduled. The nurse assesses the patient, recognizes cues, creates a generalization and hypothesis regarding the fluid status, plans and implements nursing interventions, and evaluates the outcome. Additionally, the nurse promotes patient safety by contacting the provider before administering a medication that could cause harm to the patient at this time. The ANA’s Standards of Professional Nursing Practice associated with each component of the nursing process are described below. Assessment The “Assessment” Standard of Practice is defined as, “The registered nurse collects pertinent data and information relative to the health care consumer’s health or the situation.”American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. A registered nurse uses a systematic method to collect and analyze patient data. Assessment includes physiological data, as well as psychological, sociocultural, spiritual, economic, and lifestyle data. For example, a nurse’s assessment of a hospitalized patient in pain includes the patient’s response to pain, such as the inability to get out of bed, refusal to eat, withdrawal from family members, or anger directed at hospital staff.American Nurses Association. (n.d.). The nursing process. https://www.nursingworld.org/practice-policy/workforce/what-is-nursing/the-nursing-process/ The “Assessment” component of the nursing process is further described in the “Assessment” section of this chapter. Diagnosis The “Diagnosis” Standard of Practice is defined as, “The registered nurse analyzes the assessment data to determine actual or potential diagnoses, problems, and issues.”American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. A nursing diagnosis is the nurse’s clinical judgment about the client’s response to actual or potential health conditions or needs. Nursing diagnoses are the bases for the nurse’s care plan and are different than medical diagnoses.American Nurses Association. (n.d.). The nursing process. https://www.nursingworld.org/practice-policy/workforce/what-is-nursing/the-nursing-process/ The “Diagnosis” component of the nursing process is further described in the “Diagnosis” section of this chapter. Outcomes Identification The “Outcomes Identification” Standard of Practice is defined as, “The registered nurse identifies expected outcomes for a plan individualized to the health care consumer or the situation.”American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. The nurse sets measurable and achievable short- and long-term goals and specific outcomes in collaboration with the patient based on their assessment data and nursing diagnoses. The “Outcomes Identification” component of the nursing process is further described in the “Outcomes Identification” section of this chapter. Planning The “Planning” Standard of Practice is defined as, “The registered nurse develops a collaborative plan encompassing strategies to achieve expected outcomes.”American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. Assessment data, diagnoses, and goals are used to select evidence-based nursing interventions customized to each patient’s needs and concerns. Goals, expected outcomes, and nursing interventions are documented in the patient’s nursing care plan so that nurses, as well as other health professionals, have access to it for continuity of care.American Nurses Association. (n.d.). The nursing process. https://www.nursingworld.org/practice-policy/workforce/what-is-nursing/the-nursing-process/ The “Planning” component of the nursing process is further described in the “Planning” section of this chapter. Nursing Care Plans Creating nursing care plans is a part of the “Planning” step of the nursing process. A nursing care plan is a type of documentation that demonstrates the individualized planning and delivery of nursing care for each specific patient using the nursing process. Registered nurses (RNs) create nursing care plans so that the care provided to the patient across shifts is consistent among health care personnel. Some interventions can be delegated to Licensed Practical Nurses (LPNs) or trained Unlicensed Assistive Personnel (UAPs) with the RN’s supervision. Developing nursing care plans and implementing appropriate delegation are further discussed under the “Planning” and “Implementing” sections of this chapter. Implementation The “Implementation” Standard of Practice is defined as, “The nurse implements the identified plan.”American Nurses Association. (2021). Nursing: Scope and standards of practice (3rd ed.). American Nurses Association. Nursing interventions are implemented or delegated with supervision according to the care plan to assure continuity of care across multiple nurses and health professionals caring for the patient. Interventions are also documented in the patient’s electronic medical record as they are completed.American Nurses Association. (n.d.) The nursing process. https://www.nursingworld.org/practice-policy/workforce/what-is-nursing/the-nursing-process/ The “Implementation” Standard of Professional Practice also includes the subcategories “Coordination of Care” and “Health Teaching and Health Promotion” to promote health and a safe environment.American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. The “Implementation” component of the nursing process is further described in the “Implementation” section of this chapter. Evaluation The “Evaluation” Standard of Practice is defined as, “The registered nurse evaluates progress toward attainment of goals and outcomes.”American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. During evaluation, nurses assess the patient and compare the findings against the initial assessment to determine the effectiveness of the interventions and overall nursing care plan. Both the patient’s status and the effectiveness of the nursing care must be continuously evaluated and modified as needed.American Nurses Association. (n.d.). The nursing process. https://www.nursingworld.org/practice-policy/workforce/what-is-nursing/the-nursing-process/ The “Evaluation” component of the nursing process is further described in the “Evaluation” section of this chapter. Benefits of Using the Nursing Process Using the nursing process has many benefits for nurses, patients, and other members of the health care team. The benefits of using the nursing process include the following: - Promotes quality patient care - Decreases omissions and duplications - Provides a guide for all staff involved to provide consistent and responsive care - Encourages collaborative management of a patient’s health care problems - Improves patient safety - Improves patient satisfaction - Identifies a patient’s goals and strategies to attain them - Increases the likelihood of achieving positive patient outcomes - Saves time, energy, and frustration by creating a care plan or path to follow By using these components of the nursing process as a critical thinking model, nurses plan interventions customized to the patient’s needs, plan outcomes and interventions, and determine whether those actions are effective in meeting the patient’s needs. In the remaining sections of this chapter, we will take an in-depth look at each of these components of the nursing process. Using the nursing process and implementing evidence-based practices are referred to as the “science of nursing.” Let’s review concepts related to the “art of nursing” while providing holistic care in a caring manner using the nursing process. Holistic Nursing Care The American Nurses Association (ANA) recently updated the definition of nursing as, “Nursing integrates the art and science of caring and focuses on the protection, promotion, and optimization of health and human functioning; prevention of illness and injury; facilitation of healing; and alleviation of suffering through compassionate presence. Nursing is the diagnosis and treatment of human responses and advocacy in the care of individuals, families, groups, communities, and populations in the recognition of the connection of all humanity.”American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. The ANA further describes nursing is a learned profession built on a core body of knowledge that integrates both the art and science of nursing. The art of nursing is defined as, “Unconditionally accepting the humanity of others, respecting their need for dignity and worth, while providing compassionate, comforting care.”American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. Nurses care for individuals holistically, including their emotional, spiritual, psychosocial, cultural, and physical needs. They consider problems, issues, and needs that the person experiences as a part of a family and a community as they use the nursing process. Review a scenario illustrating holistic nursing care provided to a patient and their family in the following box. The physician diagnoses the child with an ear infection and prescribes an antibiotic. The mother is advised to make a follow-up appointment with their primary provider in two weeks. While providing discharge teaching, the nurse discovers that the family is unable to afford the expensive antibiotic prescribed and cannot find a primary care provider in their community they can reach by a bus route. The nurse asks a social worker to speak with the mother about affordable health insurance options and available providers in her community and follows up with the prescribing physician to obtain a prescription for a less expensive generic antibiotic. In this manner, the nurse provides holistic care and advocates for improved health for the child and their family. Caring and the Nursing Process The American Nurses Association (ANA) states, “The act of caring is foundational to the practice of nursing.”American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. Successful use of the nursing process requires the development of a care relationship with the patient. A care relationship is a mutual relationship that requires the development of trust between both parties. This trust is often referred to as the development of rapport and underlies the art of nursing. While establishing a caring relationship, the whole person is assessed, including the individual’s beliefs, values, and attitudes, while also acknowledging the vulnerability and dignity of the patient and family. Assessing and caring for the whole person takes into account the physical, mental, emotional, and spiritual aspects of being a human being.Walivaara, B., Savenstedt, S., & Axelsson, K. (2013). Caring relationships in home-based nursing care – registered nurses’ experiences. The Open Journal of Nursing, 7, 89-95. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3722540/pdf/TONURSJ-7-89.pdf Caring interventions can be demonstrated in simple gestures such as active listening, making eye contact, touching, and verbal reassurances while also respecting and being sensitive to the care recipient’s cultural beliefs and meanings associated with caring behaviors.American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. See Figure 4.4“hospice-1793998_1280.jpg” by truthseeker08 is licensed under CC0 for an image of a nurse using touch as a therapeutic communication technique to communicate caring. Dr. Jean Watson is a nurse theorist who has published many works on the art and science of caring in the nursing profession. Her theory of human caring sought to balance the cure orientation of medicine, giving nursing its unique disciplinary, scientific, and professional standing with itself and the public. Dr. Watson’s caring philosophy encourages nurses to be authentically present with their patients while creating a healing environment.Watson Caring Science Institute. (n.d.). Watson Caring Science Institute. Jean Watson, PHD, RN, AHN-BC, FAAN, (LL-AAN). https://www.watsoncaringscience.org/jean-bio/ Now that we have discussed basic concepts related to the nursing process, let’s look more deeply at each component of the nursing process in the following sections. 4.3 Assessment Open Resources for Nursing (Open RN) Assessment is the first step of the nursing process (and the first Standard of Practice set by the American Nurses Association). This standard is defined as, “The registered nurse collects pertinent data and information relative to the health care consumer’s health or the situation.” This includes collecting “pertinent data related to the health and quality of life in a systematic, ongoing manner, with compassion and respect for the wholeness, inherent dignity, worth, and unique attributes of every person, including but not limited to, demographics, environmental and occupational exposures, social determinants of health, health disparities, physical, functional, psychosocial, emotional, cognitive, spiritual/transpersonal, sexual, sociocultural, age-related, environmental, and lifestyle/economic assessments.”American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. Nurses assess patients to gather clues, make generalizations, and diagnose human responses to health conditions and life processes. Patient data is considered either subjective or objective, and it can be collected from multiple sources. Subjective Assessment Data Subjective data is information obtained from the patient and/or family members and offers important cues from their perspectives. When documenting subjective data stated by a patient, it should be in quotation marks and start with verbiage such as, The patient reports. It is vital for the nurse to establish rapport with a patient to obtain accurate, valuable subjective data regarding the mental, emotional, and spiritual aspects of their condition. There are two types of subjective information, primary and secondary. Primary data is information provided directly by the patient. Patients are the best source of information about their bodies and feelings, and the nurse who actively listens to a patient will often learn valuable information while also promoting a sense of well-being. Information collected from a family member, chart, or other sources is known as secondary data. Family members can provide important information, especially for individuals with memory impairments, infants, children, or when patients are unable to speak for themselves. See Figure 4.5“361341143-huge.jpg” by Monkey Business Images is used under license from Shutterstock.com for an illustration of a nurse obtaining subjective data and establishing rapport after obtaining permission from the patient to sit on the bed. Example. An example of documented subjective data obtained from a patient assessment is, “The patient reports, ‘My pain is a level 2 on a 1-10 scale.’” Objective Assessment Data Objective data is anything that you can observe through your sense of hearing, sight, smell, and touch while assessing the patient. Objective data is reproducible, meaning another person can easily obtain the same data. Examples of objective data are vital signs, physical examination findings, and laboratory results. See Figure 4.6“13394660711603.jpg” by CDC/ Amanda Mills is in the Public Domain for an image of a nurse performing a physical examination. Example. An example of documented objective data is, “The patient’s radial pulse is 58 and regular, and their skin feels warm and dry.” Sources of Assessment Data There are three sources of assessment data: interview, physical examination, and review of laboratory or diagnostic test results. Interviewing Interviewing includes asking the patient questions, listening, and observing verbal and nonverbal communication. Reviewing the chart prior to interviewing the patient may eliminate redundancy in the interview process and allows the nurse to hone in on the most significant areas of concern or need for clarification. However, if information in the chart does not make sense or is incomplete, the nurse should use the interview process to verify data with the patient. After performing patient identification, the best way to initiate a caring relationship is to introduce yourself to the patient and explain your role. Share the purpose of your interview and the approximate time it will take. When beginning an interview, it may be helpful to start with questions related to the patient’s medical diagnoses to gather information about how they have affected the patient’s functioning, relationships, and lifestyle. Listen carefully and ask for clarification when something isn’t clear to you. Patients may not volunteer important information because they don’t realize it is important for their care. By using critical thinking and active listening, you may discover valuable cues that are important to provide safe, quality nursing care. Sometimes nursing students can feel uncomfortable having difficult conversations or asking personal questions due to generational or other cultural differences. Don’t shy away from asking about information that is important to know for safe patient care. Most patients will be grateful that you cared enough to ask and listen. Be alert and attentive to how the patient answers questions, as well as when they do not answer a question. Nonverbal communication and body language can be cues to important information that requires further investigation. A keen sense of observation is important. To avoid making inappropriate inferences, the nurse should validate any cues. For example, a nurse may make an inference that a patient is depressed when the patient avoids making eye contact during an interview. However, upon further questioning, the nurse may discover that the patient’s cultural background believes direct eye contact to be disrespectful and this is why they are avoiding eye contact. To read more information about communicating with patients, review the “Communication” chapter of this book. Physical Examination A physical examination is a systematic data collection method of the body that uses the techniques of inspection, auscultation, palpation, and percussion. Inspection is the observation of a patient’s anatomical structures. Auscultation is listening to sounds, such as heart, lung, and bowel sounds, created by organs using a stethoscope. Palpation is the use of touch to evaluate organs for size, location, or tenderness. Percussion is an advanced physical examination technique typically performed by providers where body parts are tapped with fingers to determine their size and if fluid is present. Detailed physical examination procedures of various body systems can be found in the Open RN Nursing Skills textbook with a head-to-toe checklist in Appendix C. Physical examination also includes the collection and analysis of vital signs. Registered Nurses (RNs) complete the initial physical examination and analyze the findings as part of the nursing process. Collection of follow-up physical examination data can be delegated to Licensed Practical Nurses/Licensed Vocational Nurses (LPNs/LVNs), or measurements such as vital signs and weight may be delegated to trained Unlicensed Assistive Personnel (UAP) when appropriate to do so. However, the RN remains responsible for supervising these tasks, analyzing the findings, and ensuring they are documented . A physical examination can be performed as a comprehensive, head-to-toe assessment or as a focused assessment related to a particular condition or problem. Assessment data is documented in the patient’s Electronic Medical Record (EMR), an electronic version of the patient’s medical chart. Reviewing Laboratory and Diagnostic Test Results Reviewing laboratory and diagnostic test results provides relevant and useful information related to the needs of the patient. Understanding how normal and abnormal results affect patient care is important when implementing the nursing care plan and administering provider prescriptions. If results cause concern, it is the nurse’s responsibility to notify the provider and verify the appropriateness of prescriptions based on the patient’s current status before implementing them. Types of Assessments Several types of nursing assessment are used in clinical practice: - Primary Survey: Used during every patient encounter to briefly evaluate level of consciousness, airway, breathing, and circulation and implement emergency care if needed. - Admission Assessment: A comprehensive assessment completed when a patient is admitted to a facility that involves assessing a large amount of information using an organized approach. - Ongoing Assessment: In acute care agencies such as hospitals, a head-to-toe assessment is completed and documented at least once every shift. Any changes in patient condition are reported to the health care provider. - Focused Assessment: Focused assessments are used to reevaluate the status of a previously diagnosed problem. - Time-lapsed Reassessment: Time-lapsed reassessments are used in long-term care facilities when three or more months have elapsed since the previous assessment to evaluate progress on previously identified outcomes.Gordon, M. (2008). Assess notes: Nursing assessment and diagnostic reasoning. F.A. Davis Company. Putting It Together Review Scenario C in the following box to apply concepts of assessment to a patient scenario. Scenario C“grandmother-1546855_960_720.jpg” by vendie4u is licensed under CC0 Ms. J. is a 74-year-old woman who is admitted directly to the medical unit after visiting her physician because of shortness of breath, increased swelling in her ankles and calves, and fatigue. Her medical history includes hypertension (30 years), coronary artery disease (18 years), heart failure (2 years), and type 2 diabetes (14 years). She takes 81 mg of aspirin every day, metoprolol 50 mg twice a day, furosemide 40 mg every day, and metformin 2,000 mg every day. Ms. J.’s vital sign values on admission were as follows: - Blood Pressure: 162/96 mm Hg - Heart Rate: 88 beats/min - Oxygen Saturation: 91% on room air - Respiratory Rate: 28 breaths/minute - Temperature: 97.8 degrees F orally Her weight is up 10 pounds since the last office visit three weeks prior. The patient states, “I am so short of breath” and “My ankles are so swollen I have to wear my house slippers.” Ms. J. also shares, “I am so tired and weak that I can’t get out of the house to shop for groceries,” and “Sometimes I’m afraid to get out of bed because I get so dizzy.” She confides, “I would like to learn more about my health so I can take better care of myself.” The physical assessment findings of Ms. J. are bilateral basilar crackles in the lungs and bilateral 2+ pitting edema of the ankles and feet. Laboratory results indicate a decreased serum potassium level of 3.4 mEq/L. As the nurse completes the physical assessment, the patient’s daughter enters the room. She confides, “We are so worried about mom living at home by herself when she is so tired all the time!” Critical Thinking Questions - Identify subjective data. - Identify objective data. - Provide an example of secondary data. Answers are located in the Answer Key at the end of the book. 4.4 Diagnosis Open Resources for Nursing (Open RN) Diagnosis is the second step of the nursing process (and the second Standard of Practice set by the American Nurses Association). This standard is defined as, “The registered nurse analyzes assessment data to determine actual or potential diagnoses, problems, and issues.” The RN “prioritizes diagnoses, problems, and issues based on mutually established goals to meet the needs of the health care consumer across the health–illness continuum and the care continuum.” Diagnoses, problems, strengths, and issues are documented in a manner that facilitates the development of expected outcomes and a collaborative plan.American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. Analyzing Assessment Data After collection of assessment data, the registered nurse analyzes the data to form generalizations and create hypotheses for nursing diagnoses. Steps for analyzing assessment data include performing data analysis, clustering of information, identifying hypotheses for potential nursing diagnosis, performing additional in-depth assessment as needed, and establishing nursing diagnosis statements. The nursing diagnoses are then prioritized and drive the nursing care plan.Herdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York. Performing Data Analysis After nurses collect assessment data from a patient, they use their nursing knowledge to analyze that data to determine if it is “expected” or “unexpected” or “normal” or “abnormal” for that patient according to their age, development, and baseline status. From there, nurses determine what data are “clinically relevant” as they prioritize their nursing care.Herdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York. Example. In Scenario C in the “Assessment” section of this chapter, the nurse analyzes the vital signs data and determines the blood pressure, heart rate, and respiratory rate are elevated, and the oxygen saturation is decreased for this patient. These findings are considered “relevant cues.” Clustering Information/Seeing Patterns/Making Hypotheses After analyzing the data and determining relevant cues, the nurse clusters data into patterns. Assessment frameworks such as Gordon’s Functional Health Patterns assist nurses in clustering information according to evidence-based patterns of human responses. See the box below for an outline of Gordon’s Functional Health Patterns.Gordon, M. (2008). Assess notes: Nursing assessment and diagnostic reasoning. F.A. Davis Company. Concepts related to many of these patterns will be discussed in chapters later in this book. Example. Refer to Scenario C of the “Assessment” section of this chapter. The nurse clusters the following relevant cues: elevated blood pressure, elevated respiratory rate, crackles in the lungs, weight gain, worsening edema, shortness of breath, a medical history of heart failure, and currently prescribed a diuretic medication. These cues are clustered into a generalization/pattern of fluid balance, which can be classified under Gordon’s Nutritional-Metabolic Functional Health Pattern. The nurse makes a hypothesis that the patient has excess fluid volume present. Gordon’s Functional Health PatternsGordon, M. (2008). Assess notes: Nursing assessment and diagnostic reasoning. F.A. Davis Company. Health Perception-Health Management: A patient’s perception of their health and well-being and how it is managed Nutritional-Metabolic: Food and fluid consumption relative to metabolic need Elimination: Excretory function, including bowel, bladder, and skin Activity-Exercise: Exercise and daily activities Sleep-Rest: Sleep, rest, and daily activities Cognitive-Perceptual: Perception and cognition Self-perception and Self-concept: Self-concept and perception of self-worth, self-competency, body image, and mood state Role-Relationship: Role engagements and relationships Sexuality-Reproductive: Reproduction and satisfaction or dissatisfaction with sexuality Coping-Stress Tolerance: Coping and effectiveness in terms of stress tolerance Value-Belief: Values, beliefs (including spiritual beliefs), and goals that guide choices and decisions Identifying Nursing Diagnoses After the nurse has analyzed and clustered the data from the patient assessment, the next step is to begin to answer the question, “What are my patient’s human responses (i.e., nursing diagnoses)?” A nursing diagnosis is defined as, “A clinical judgment concerning a human response to health conditions/life processes, or a vulnerability for that response, by an individual, family, group, or community.”Herdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York. Nursing diagnoses are customized to each patient and drive the development of the nursing care plan. The nurse should refer to a care planning resource and review the definitions and defining characteristics of the hypothesized nursing diagnoses to determine if additional in-depth assessment is needed before selecting the most accurate nursing diagnosis. Nursing diagnoses are developed by nurses, for use by nurses. For example, NANDA International (NANDA-I) is a global professional nursing organization that develops nursing terminology that names actual or potential human responses to health problems and life processes based on research findings.Herdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York. Currently, there are over 220 NANDA-I nursing diagnoses developed by nurses around the world. This list is continuously updated, with new nursing diagnoses added and old nursing diagnoses retired that no longer have supporting evidence. A list of commonly used NANDA-I diagnoses are listed in Appendix A. For a full list of NANDA-I nursing diagnoses, refer to a current nursing care plan reference. NANDA-I nursing diagnoses are grouped into 13 domains that assist the nurse in selecting diagnoses based on the patterns of clustered data. These domains are similar to Gordon’s Functional Health Patterns and include health promotion, nutrition, elimination and exchange, activity/rest, perception/cognition, self-perception, role relationship, sexuality, coping/stress tolerance, life principles, safety/protection, comfort, and growth/development. Nursing Diagnoses vs. Medical Diagnoses You may be asking yourself, “How are nursing diagnoses different from medical diagnoses?” Medical diagnoses focus on diseases or other medical problems that have been identified by the physician, physician’s assistant, or advanced nurse practitioner. Nursing diagnoses focus on the human response to health conditions and life processes and are made independently by RNs. Patients with the same medical diagnosis will often respond differently to that diagnosis and thus have different nursing diagnoses. For example, two patients have the same medical diagnosis of heart failure. However, one patient may be interested in learning more information about the condition and the medications used to treat it, whereas another patient may be experiencing anxiety when thinking about the effects this medical diagnosis will have on their family. The nurse must consider these different responses when creating the nursing care plan. Nursing diagnoses consider the patient’s and family’s needs, attitudes, strengths, challenges, and resources as a customized nursing care plan is created to provide holistic and individualized care for each patient. Example. A medical diagnosis identified for Ms. J. in Scenario C in the “Assessment” section is heart failure. This cannot be used as a nursing diagnosis, but it can be considered as an “associated condition” when creating hypotheses for nursing diagnoses. Associated conditions are medical diagnoses, injuries, procedures, medical devices, or pharmacological agents that are not independently modifiable by the nurse, but support accuracy in nursing diagnosis. The nursing diagnosis in Scenario C will be related to the patient’s response to heart failure. Additional Definitions Used in NANDA-I Nursing Diagnoses The following definitions of patient, age, and time are used in association with NANDA-I nursing diagnoses: Patient The NANDA-I definition of a “patient” includes: - Individual: a single human being distinct from others (i.e., a person). - Caregiver: a family member or helper who regularly looks after a child or a sick, elderly, or disabled person. - Family: two or more people having continuous or sustained relationships, perceiving reciprocal obligations, sensing common meaning, and sharing certain obligations toward others; related by blood and/or choice. - Group: a number of people with shared characteristics generally referred to as an ethnic group. - Community: a group of people living in the same locale under the same governance. Examples include neighborhoods and cities.NANDA International. (n.d.). Glossary of terms. https://nanda.org/nanda-i-resources/glossary-of-terms/ Age The age of the person who is the subject of the diagnosis is defined by the following terms:NANDA International. (n.d.). Glossary of terms. https://nanda.org/nanda-i-resources/glossary-of-terms/ - Fetus: an unborn human more than eight weeks after conception, until birth. - Neonate: a person less than 28 days of age. - Infant: a person greater than 28 days and less than 1 year of age. - Child: a person aged 1 to 9 years - Adolescent: a person aged 10 to 19 years - Adult: a person older than 19 years of age unless national law defines a person as being an adult at an earlier age. - Older adult: a person greater than 65 years of age. Time The duration of the diagnosis is defined by the following terms:NANDA International. (n.d.). Glossary of terms. https://nanda.org/nanda-i-resources/glossary-of-terms/ - Acute: lasting less than 3 months. - Chronic: lasting greater than 3 months. - Intermittent: stopping or starting again at intervals - Continuous: uninterrupted, going on without stop. New Terms Used in 2018-2020 NANDA-I Diagnoses The 2018-2020 edition of Nursing Diagnoses includes two new terms to assist in creating nursing diagnoses: at-risk populations and associated conditions.Herdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York. At-Risk Populations are groups of people who share a characteristic that causes each member to be susceptible to a particular human response, such as demographics, health/family history, stages of growth/development, or exposure to certain events/experiences. Associated Conditions are medical diagnoses, injuries, procedures, medical devices, or pharmacological agents. These conditions are not independently modifiable by the nurse, but support accuracy in nursing diagnosisHerdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York. Types of Nursing Diagnoses There are four types of NANDA-I nursing diagnoses:NANDA International. (n.d.). Glossary of terms. https://nanda.org/nanda-i-resources/glossary-of-terms/ - Problem-Focused - Health Promotion – Wellness - Risk - Syndrome A problem-focused nursing diagnosis is a “clinical judgment concerning an undesirable human response to health condition/life processes that exist in an individual, family, group, or community.”NANDA International. (n.d.). Glossary of terms. https://nanda.org/nanda-i-resources/glossary-of-terms/ To make an accurate problem-focused diagnosis, related factors and defining characteristics must be present. Related factors (also called etiology) are causes that contribute to the diagnosis. Defining characteristics are cues, signs, and symptoms that cluster into patterns.NANDA International. (n.d.). Glossary of terms. https://nanda.org/nanda-i-resources/glossary-of-terms/ A health promotion-wellness nursing diagnosis is “a clinical judgment concerning motivation and desire to increase well-being and to actualize human health potential.” These responses are expressed by the patient’s readiness to enhance specific health behaviors.NANDA International. (n.d.). Glossary of terms. https://nanda.org/nanda-i-resources/glossary-of-terms/A health promotion-wellness diagnosis is used when the patient is willing to improve a lack of knowledge, coping, or other identified need. A risk nursing diagnosis is “a clinical judgment concerning the vulnerability of an individual, family, group, or community for developing an undesirable human response to health conditions/life processes.”NANDA International. (n.d.). Glossary of terms. https://nanda.org/nanda-i-resources/glossary-of-terms/ A risk nursing diagnosis must be supported by risk factors that contribute to the increased vulnerability. A risk nursing diagnosis is different from the problem-focused diagnosis in that the problem has not yet actually occurred. Problem diagnoses should not be automatically viewed as more important than risk diagnoses because sometimes a risk diagnosis can have the highest priority for a patient.Herdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York. A syndrome diagnosis is a “clinical judgment concerning a specific cluster of nursing diagnoses that occur together, and are best addressed together and through similar interventions.”NANDA International. (n.d.). Glossary of terms. https://nanda.org/nanda-i-resources/glossary-of-terms/ Establishing Nursing Diagnosis Statements When using NANDA-I nursing diagnoses, NANDA-I recommends the structure of a nursing diagnosis should be a statement that includes the nursing diagnosis and related factors as exhibited by defining characteristics. The accuracy of the nursing diagnosis is validated when a nurse is able to clearly link the defining characteristics, related factors, and/or risk factors found during the patient’s assessment.Herdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York. To create a nursing diagnosis statement, the registered nurse completes the following steps. After analyzing the patient’s subjective and objective data and clustering the data into patterns, the nurse generates hypotheses for nursing diagnoses based on how the patterns meet defining characteristics of a nursing diagnosis. Defining characteristics is the terminology used for observable signs and symptoms related to a nursing diagnosis.Herdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York. Defining characteristics are included in care planning resources for each nursing diagnosis, along with a definition of that diagnosis, so the nurse can select the most accurate diagnosis. For example, objective and subjective data such as weight, height, and dietary intake can be clustered together as defining characteristics for the nursing diagnosis of nutritional status. When creating a nursing diagnosis statement, the nurse also identifies the cause of the problem for that specific patient. Related factors is the terminology used for the underlying causes (etiology) of a patient’s problem or situation. Related factors should not be a medical diagnosis, but instead should be attributed to the underlying pathophysiology that the nurse can treat. When possible, the nursing interventions planned for each nursing diagnosis should attempt to modify or remove these related factors that are the underlying cause of the nursing diagnosis.Herdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York. Creating nursing diagnosis statements has traditionally been referred to as “using PES format.” The PES mnemonic no longer applies to the current terminology used by NANDA-I, but the components of a nursing diagnosis statement remain the same. A nursing diagnosis statement should contain the problem, related factors, and defining characteristics. These terms fit under the former PES format in this manner: Problem (P) – the patient problem (i.e., the nursing diagnosis) Etiology (E) – related factors (i.e., the etiology/cause) of the nursing diagnosis; phrased as “related to” or “R/T” Signs and Symptoms (S) – defining characteristics manifested by the patient (i.e., the signs and symptoms/subjective and objective data) that led to the identification of that nursing diagnosis for the patient; phrased with “as manifested by” or “as evidenced by.” Examples of different types of nursing diagnoses are further explained below. Problem-Focused Nursing Diagnosis A problem-focused nursing diagnosis contains all three components of the PES format: Problem (P) – statement of the patient response (nursing diagnosis) Etiology (E) – related factors contributing to the nursing diagnosis Signs and Symptoms (S) – defining characteristics manifested by that patient Sample Problem-Focused Nursing Diagnosis Statement Refer to Scenario C of the “Assessment” section of this chapter. The cluster of data for Ms. J. (elevated blood pressure, elevated respiratory rate, crackles in the lungs, weight gain, worsening edema, and shortness of breath) are defining characteristics for the NANDA-I Nursing Diagnosis Excess Fluid Volume. The NANDA-I definition of Excess Fluid Volume is “surplus intake and/or retention of fluid.” The related factor (etiology) of the problem is that the patient has excessive fluid intake.Herdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York. Example The components of a problem-focused nursing diagnosis statement for Ms. J. would be: (P) Fluid Volume Excess (E) Related to excessive fluid intake (S) As manifested by bilateral basilar crackles in the lungs, bilateral 2+ pitting edema of the ankles and feet, increased weight of 10 pounds, and the patient reports, “My ankles are so swollen.” A correctly written problem-focused nursing diagnosis statement for Ms. J. would look like this: Fluid Volume Excess related to excessive fluid intake as manifested by bilateral basilar crackles in the lungs, bilateral 2+ pitting edema of the ankles and feet, an increase weight of 10 pounds, and the patient reports, “My ankles are so swollen.” Health-Promotion Nursing Diagnosis A health-promotion nursing diagnosis statement contains the problem (P) and the defining characteristics (S). The defining characteristics component of a health-promotion nursing diagnosis statement should begin with the phrase “expresses desire to enhance”:NANDA International. (n.d.). Glossary of terms. https://nanda.org/nanda-i-resources/glossary-of-terms/ Problem (P) – statement of the patient response (nursing diagnosis) Signs and Symptoms (S) – the patient’s expressed desire to enhance Sample Health-Promotion Nursing Diagnosis Statement Refer to Scenario C in the “Assessment” section of this chapter. Ms. J. demonstrates a readiness to improve her health status when she told the nurse that she would like to “learn more about my health so I can take better care of myself.” This statement is a defining characteristic of the NANDA-I nursing diagnosis Readiness for Enhanced Health Management, which is defined as “a pattern of regulating and integrating into daily living a therapeutic regimen for the treatment of illness and its sequelae, which can be strengthened.”Herdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York. Example The components of a health-promotion nursing diagnosis for Ms. J. would be: Problem (P): Readiness for Enhanced Health Management Symptoms (S): Expressed desire to “learn more about my health so I can take better care of myself.” A correctly written health-promotion nursing diagnosis statement for Ms. J. would look like this: Enhanced Readiness for Health Promotion as manifested by expressed desire to “learn more about my health so I can take better care of myself.” Risk Nursing Diagnosis A risk nursing diagnosis should be supported by evidence of the patient’s risk factors for developing that problem. Different experts recommend different phrasing. NANDA-I 2018-2020 recommends using the phrase “as evidenced by” to refer to the risk factors for developing that problem.NANDA International. (n.d.). Glossary of terms. https://nanda.org/nanda-i-resources/glossary-of-terms/ A risk diagnosis consists of the following: Problem (P) – statement of the patient response (nursing diagnosis) As Evidenced By – Risk factors for developing the problem Sample Risk Diagnosis Statement Refer to Scenario C in the “Assessment” section of this chapter. Ms. J. has an increased risk of falling due to vulnerability from the dizziness and weakness she is experiencing. The NANDA-I definition of Risk for Falls is “increased susceptibility to falling, which may cause physical harm and compromise health.”Herdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York. Example The components of a risk diagnosis statement for Ms. J. would be: Problem (P) – Risk for Falls As Evidenced By – Dizziness and decreased lower extremity strength A correctly written risk nursing diagnosis statement for Ms. J. would look like this: Risk for Falls as evidenced by dizziness and decreased lower extremity strength. Syndrome Diagnosis A syndrome is a cluster of nursing diagnoses that occur together and are best addressed together and through similar interventions. To create a syndrome diagnosis, two or more nursing diagnoses must be used as defining characteristics (S) that create a syndrome. Related factors may be used if they add clarity to the definition, but are not required.NANDA International. (n.d.). Glossary of terms. https://nanda.org/nanda-i-resources/glossary-of-terms/ A syndrome statement consists of these items: Problem (P) – the syndrome Signs and Symptoms (S) – the defining characteristics are two or more similar nursing diagnoses Sample Syndrome Diagnosis Statement Refer to Scenario C in the “Assessment” section of this chapter. Clustering the data for Ms. J. identifies several similar NANDA-I nursing diagnoses that can be categorized as a syndrome. For example, Activity Intolerance is defined as “insufficient physiological or psychological energy to endure or complete required or desired daily activities.” Social Isolation is defined as “aloneness experienced by the individual and perceived as imposed by others and as a negative or threatening state.” These diagnoses can be included under the the NANDA-I syndrome named Risk for Frail Elderly Syndrome. This syndrome is defined as a “dynamic state of unstable equilibrium that affects the older individual experiencing deterioration in one or more domains of health (physical, functional, psychological, or social) and leads to increased susceptibility to adverse health effects, in particular disability.”Herdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York. Example The components of a syndrome nursing diagnosis for Ms. J. would be: (P) – Risk for Frail Elderly Syndrome (S) – The nursing diagnoses of Activity Intolerance and Social Isolation Additional related factor: Fear of falling A correctly written syndrome diagnosis statement for Ms. J. would look like this: Risk for Frail Elderly Syndrome related to activity intolerance, social isolation, and fear of falling Prioritization After identifying nursing diagnoses, the next step is prioritization according to the specific needs of the patient. Nurses prioritize their actions while providing patient care multiple times every day. Prioritization is the process that identifies the most significant nursing problems, as well as the most important interventions, in the nursing care plan. It is essential that life-threatening concerns and crises are identified immediately and addressed quickly. Depending on the severity of a problem, the steps of the nursing process may be performed in a matter of seconds for life-threatening concerns. In critical situations, the steps of the nursing process are performed through rapid clinical judgment. Nurses must recognize cues signaling a change in patient condition, apply evidence-based practices in a crisis, and communicate effectively with interprofessional team members. Most patient situations fall somewhere between a crisis and routine care. There are several concepts used to prioritize, including Maslow’s Hierarchy of Needs, the “ABCs” (Airway, Breathing and Circulation), and acute, uncompensated conditions. See the infographic in Figure 4.7“The How To of Prioritization” by Valerie Palarski for Chippewa Valley Technical College is licensed under CC BY 4.0 on The How To of Prioritization. Maslow’s Hierarchy of Needs is used to categorize the most urgent patient needs. The bottom levels of the pyramid represent the top priority needs of physiological needs intertwined with safety. See Figure 4.8“Maslow’s hierarchy of needs.svg” by J. Finkelstein is licensed under CC BY-SA 3.0 for an image of Maslow’s Hierarchy of Needs. You may be asking yourself, “What about the ABCs – isn’t airway the most important?” The answer to that question is “it depends on the situation and the associated safety considerations.” Consider this scenario – you are driving home after a lovely picnic in the country and come across a fiery car crash. As you approach the car, you see that the passenger is not breathing. Using Maslow’s Hierarchy of Needs to prioritize your actions, you remove the passenger from the car first due to safety even though he is not breathing. After ensuring safety and calling for help, you follow the steps to perform cardiopulmonary resuscitation (CPR) to establish circulation, airway, and breathing until help arrives. In addition to using Maslow’s Hierarchy of Needs and the ABCs of airway, breathing, and circulation, the nurse also considers if the patient’s condition is an acute or chronic problem. Acute, uncompensated conditions generally require priority interventions over chronic conditions. Additionally, actual problems generally receive priority over potential problems, but risk problems sometimes receive priority depending on the patient vulnerability and risk factors. Example. Refer to Scenario C in the “Assessment” section of this chapter. Four types of nursing diagnoses were identified for Ms. J.: Fluid Volume Excess, Enhanced Readiness for Health Promotion, Risk for Falls, and Risk for Frail Elderly Syndrome. The top priority diagnosis is Fluid Volume Excess because it affects the physiological needs of breathing, homeostasis, and excretion. However, the Risk for Falls diagnosis comes in a close second because of safety implications and potential injury that could occur if the patient fell. 4.5 Outcome Identification Open Resources for Nursing (Open RN) Outcome Identification is the third step of the nursing process (and the third Standard of Practice set by the American Nurses Association). This standard is defined as, “The registered nurse identifies expected outcomes for a plan individualized to the health care consumer or the situation.” The RN collaborates with the health care consumer, interprofessional team, and others to identify expected outcomes integrating the health care consumer’s culture, values, and ethical considerations. Expected outcomes are documented as measurable goals with a time frame for attainment.American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. An outcome is a “measurable behavior demonstrated by the patient responsive to nursing interventions.”Herdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York. Outcomes should be identified before nursing interventions are planned. After nursing interventions are implemented, the nurse will evaluate if the outcomes were met in the time frame indicated for that patient. Outcome identification includes setting short- and long-term goals and then creating specific expected outcome statements for each nursing diagnosis. Short-Term and Long-Term Goals Nursing care should always be individualized and patient-centered. No two people are the same, and neither should nursing care plans be the same for two people. Goals and outcomes should be tailored specifically to each patient’s needs, values, and cultural beliefs. Patients and family members should be included in the goal-setting process when feasible. Involving patients and family members promotes awareness of identified needs, ensures realistic goals, and motivates their participation in the treatment plan to achieve the mutually agreed upon goals and live life to the fullest with their current condition. The nursing care plan is a road map used to guide patient care so that all health care providers are moving toward the same patient goals. Goals are broad statements of purpose that describe the overall aim of care. Goals can be short- or long-term. The time frame for short- and long-term goals is dependent on the setting in which the care is provided. For example, in a critical care area, a short-term goal might be set to be achieved within an 8-hour nursing shift, and a long-term goal might be in 24 hours. In contrast, in an outpatient setting, a short-term goal might be set to be achieved within one month and a long-term goal might be within six months. A nursing goal is the overall direction in which the patient must progress to improve the problem/nursing diagnosis and is often the opposite of the problem. Example. Refer to Scenario C in the “Assessment” section of this chapter. Ms. J. had a priority nursing diagnosis of Fluid Volume Excess. A broad goal would be, “Ms. J. will achieve a state of fluid balance.” Expected Outcomes Goals are broad, general statements, but outcomes are specific and measurable. Expected outcomes are statements of measurable action for the patient within a specific time frame that are responsive to nursing interventions. Nurses may create expected outcomes independently or refer to classification systems for assistance. Just as NANDA-I creates and revises standardized nursing diagnoses, a similar classification and standardization process exists for expected nursing outcomes. The Nursing Outcomes Classification (NOC) is a list of over 330 nursing outcomes designed to coordinate with established NANDA-I diagnoses.Johnson, M., Moorhead, S., Bulechek, G., Butcher, H., Maas, M., & Swanson, E. (2012). NOC and NIC linkages to NANDA-I and clinical conditions: Supporting critical reasoning and quality care. Elsevier. Patient-Centered Outcome statements are always patient-centered. They should be developed in collaboration with the patient and individualized to meet a patient’s unique needs, values, and cultural beliefs. They should start with the phrase “The patient will…” Outcome statements should be directed at resolving the defining characteristics for that nursing diagnosis. Additionally, the outcome must be something the patient is willing to cooperate in achieving. Outcome statements should contain five components easily remembered using the “SMART” mnemonic:Campbell, J. (2020). SMART criteria. Salem Press Encyclopedia. - Specific - Measurable - Attainable/Action oriented - Relevant/Realistic - Timeframe See Figure 4.9“SMART-goals.png” by Dungdm93 is licensed under CC BY-SA 4.0 for an image of the SMART components of outcome statements. Each of these components is further described in the following subsections. Specific Outcome statements should state precisely what is to be accomplished. See the following examples: - Not specific: “The patient will increase the amount of exercise.” - Specific: “The patient will participate in a bicycling exercise session daily for 30 minutes.” Additionally, only one action should be included in each expected outcome. See the following examples: - “The patient will walk 50 feet three times a day with standby assistance of one and will shower in the morning until discharge” is actually two goals written as one. The outcome of ambulation should be separate from showering for precise evaluation. For instance, the patient could shower but not ambulate, which would make this outcome statement very difficult to effectively evaluate. - Suggested revision is to create two outcomes statements so each can be measured: The patient will walk 50 feet three times a day with standby assistance of one until discharge. The patient will shower every morning until discharge. Measurable Measurable outcomes have numeric parameters or other concrete methods of judging whether the outcome was met. It is important to use objective data to measure outcomes. If terms like “acceptable” or “normal” are used in an outcome statement, it is difficult to determine whether the outcome is attained. Refer to Figure 4.10“Measurable Outcomes” by Valerie Palarski for Chippewa Valley Technical College is licensed under CC BY 4.0 for examples of verbs that are measurable and not measurable in outcome statements. See the following examples: - Not measurable: “The patient will drink adequate fluid amounts every shift.” - Measurable: “The patient will drink 24 ounces of fluids during every day shift (0600-1400).” Action-Oriented and Attainable Outcome statements should be written so that there is a clear action to be taken by the patient or significant others. This means that the outcome statement should include a verb. Refer to Figure 4.11“Action Verbs” by Valerie Palarski for Chippewa Valley Technical College is licensed under CC BY 4.0 for examples of action verbs. See the following examples: - Not action-oriented: “The patient will get increased physical activity.” - Action-oriented: “The patient will list three types of aerobic activity that he would enjoy completing every week.” Realistic and Relevant Realistic outcomes consider the patient’s physical and mental condition; their cultural and spiritual values, beliefs, and preferences; and their socioeconomic status in terms of their ability to attain these outcomes. Consideration should be also given to disease processes and the effects of conditions such as pain and decreased mobility on the patient’s ability to reach expected outcomes. Other barriers to outcome attainment may be related to health literacy or lack of available resources. Outcomes should always be reevaluated and revised for attainability as needed. If an outcome is not attained, it is commonly because the original time frame was too ambitious or the outcome was not realistic for the patient. See the following examples: - Not realistic: “The patient will jog one mile every day when starting the exercise program.” - Realistic: “The patient will walk ½ mile three times a week for two weeks.” Time Limited Outcome statements should include a time frame for evaluation. The time frame depends on the intervention and the patient’s current condition. Some outcomes may need to be evaluated every shift, whereas other outcomes may be evaluated daily, weekly, or monthly. During the evaluation phase of the nursing process, the outcomes will be assessed according to the time frame specified for evaluation. If it has not been met, the nursing care plan should be revised. See the following examples: - Not time limited: “The patient will stop smoking cigarettes.” - Time limited: “The patient will complete the smoking cessation plan by December 12, 2021.” Putting It Together In Scenario C in Box 4.3, Ms. J.’s priority nursing diagnosis statement was Fluid Volume Excess related to excess fluid intake as manifested by bilateral basilar crackles in the lungs, bilateral 2+ pitting edema of the ankles and feet, an increase weight of 10 pounds, and the patient reports, “My ankles are so swollen.” An example of an expected outcome meeting SMART criteria for Ms. J. is, “The patient will have clear bilateral lung sounds within the next 24 hours.” 4.6 Planning Open Resources for Nursing (Open RN) Planning is the fourth step of the nursing process (and the fourth Standard of Practice set by the American Nurses Association). This standard is defined as, “The registered nurse develops a collaborative plan encompassing strategies to achieve expected outcomes.” The RN develops an individualized, holistic, evidence-based plan in partnership with the health care consumer, family, significant others, and interprofessional team. Elements of the plan are prioritized. The plan is modified according to the ongoing assessment of the health care consumer’s response and other indicators. The plan is documented using standardized language or terminology.American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. After expected outcomes are identified, the nurse begins planning nursing interventions to implement. Nursing interventions are evidence-based actions that the nurse performs to achieve patient outcomes. Just as a provider makes medical diagnoses and writes prescriptions to improve the patient’s medical condition, a nurse formulates nursing diagnoses and plans nursing interventions to resolve patient problems. Nursing interventions should focus on eliminating or reducing the related factors (etiology) of the nursing diagnoses when possible.Herdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York. Nursing interventions, goals, and expected outcomes are written in the nursing care plan for continuity of care across shifts, nurses, and health professionals. Planning Nursing Interventions You might be asking yourself, “How do I know what evidence-based nursing interventions to include in the nursing care plan?” There are several sources that nurses and nursing students can use to select nursing interventions. Many agencies have care planning tools and references included in the electronic health record that are easily documented in the patient chart. Nurses can also refer to other care planning books our sources such as the Nursing Interventions Classification (NIC) system. Based on research and input from the nursing profession, NIC categorizes and describes nursing interventions that are constantly evaluated and updated. Interventions included in NIC are considered evidence-based nursing practices. The nurse is responsible for using clinical judgment to make decisions about which interventions are best suited to meet an individualized patient’s needs.Butcher, H. K., Bulechek, G. M., Dochterman, J. M., & Wagner, C. M. (2018). Nursing interventions classifications (NIC) (7th ed.). Elsevier. Direct and Indirect Care Nursing interventions are considered direct care or indirect care. Direct care refers to interventions that are carried out by having personal contact with patients. Examples of direct care interventions are wound care, repositioning, and ambulation. Indirect care interventions are performed when the nurse provides assistance in a setting other than with the patient. Examples of indirect care interventions are attending care conferences, documenting, and communicating about patient care with other providers. Classification of Nursing Interventions There are three types of nursing interventions: independent, dependent, and collaborative. (See Figure 4.12“400845937-huge.jpg” by Flamingo Images is used under license from Shutterstock.com for an image of a nurse collaborating with the health care team when planning interventions.) Independent Nursing Interventions Any intervention that the nurse can independently provide without obtaining a prescription is considered an independent nursing intervention. An example of an independent nursing intervention is when the nurses monitor the patient’s 24-hour intake/output record for trends because of a risk for imbalanced fluid volume. Another example of independent nursing interventions is the therapeutic communication that a nurse uses to assist patients to cope with a new medical diagnosis. Example. Refer to Scenario C in the “Assessment” section of this chapter. Ms. J. was diagnosed with Fluid Volume Excess. An example of an evidence-based independent nursing intervention is, “The nurse will reposition the patient with dependent edema frequently, as appropriate.”Butcher, H. K., Bulechek, G. M., Dochterman, J. M., & Wagner, C. M. (2018). Nursing interventions classifications (NIC) (7th ed.). Elsevier. The nurse would individualize this evidence-based intervention to the patient and agency policy by stating, “The nurse will reposition the patient every 2 hours.” Dependent Nursing Interventions Dependent nursing interventions require a prescription before they can be performed. Prescriptions are orders, interventions, remedies, or treatments ordered or directed by an authorized primary health care provider.NCSBN. (n.d.). 2019 NCLEX-RN test plan. https://www.ncsbn.org/2019_RN_TestPlan-English.htm A primary health care provider is a member of the health care team (usually a physician, advanced practice nurse, or physician’s assistant) who is licensed and authorized to formulate prescriptions on behalf of the client. For example, administering medication is a dependent nursing intervention. The nurse incorporates dependent interventions into the patient’s overall care plan by associating each intervention with the appropriate nursing diagnosis. Example. Refer to Scenario C in the “Assessment” section of this chapter. Ms. J. was diagnosed with Fluid Volume Excess. An example of a dependent nursing intervention is, “The nurse will administer scheduled diuretics as prescribed.” Collaborative Nursing Interventions Collaborative nursing interventions are actions that the nurse carries out in collaboration with other health team members, such as physicians, social workers, respiratory therapists, physical therapists, and occupational therapists. These actions are developed in consultation with other health care professionals and incorporate their professional viewpoint.Vera, M. (2020). Nursing care plan (NCP): Ultimate guide and database. https://nurseslabs.com/nursing-care-plans/#:~:text=Collaborative%20interventions%20are%20actions%20that,to%20gain%20their%20professional%20viewpoint. Example. Refer to Scenario C in the “Assessment” section of this chapter. Ms. J. was diagnosed with Fluid Volume Excess. An example of a collaborative nursing intervention is consulting with a respiratory therapist when the patient has deteriorating oxygen saturation levels. The respiratory therapist plans oxygen therapy and obtains a prescription from the provider. The nurse would document “The nurse will manage oxygen therapy in collaboration with the respiratory therapist” in the care plan. Individualization of Interventions It is vital for the planned interventions to be individualized to the patient to be successful. For example, adding prune juice to the breakfast meal of a patient with constipation will only work if the patient likes to drink the prune juice. If the patient does not like prune juice, then this intervention should not be included in the care plan. Collaboration with the patient, family members, significant others, and the interprofessional team is essential for selecting effective interventions. The number of interventions included in a nursing care plan is not a hard and fast rule, but enough quality, individualized interventions should be planned to meet the identified outcomes for that patient. Creating Nursing Care Plans Nursing care plans are created by registered nurses (RNs). Documentation of individualized nursing care plans are legally required in long-term care facilities by the Centers for Medicare and Medicaid Services (CMS) and in hospitals by The Joint Commission. CMS guidelines state, “Residents and their representative(s) must be afforded the opportunity to participate in their care planning process and to be included in decisions and changes in care, treatment, and/or interventions. This applies both to initial decisions about care and treatment, as well as the refusal of care or treatment. Facility staff must support and encourage participation in the care planning process. This may include ensuring that residents, families, or representatives understand the comprehensive care planning process, holding care planning meetings at the time of day when a resident is functioning best and patient representatives can be present, providing sufficient notice in advance of the meeting, scheduling these meetings to accommodate a resident’s representative (such as conducting the meeting in-person, via a conference call, or video conferencing), and planning enough time for information exchange and decision-making. A resident has the right to select or refuse specific treatment options before the care plan is instituted.”Centers for Medicare and Medicaid Services. (2017). State operations manual: Appendix PP – Guidance to surveyors for long term care facilities. https://www.cms.gov/Regulations-and-Guidance/Guidance/Manuals/downloads/som107ap_pp_guidelines_ltcf.pdf The Joint Commission conceptualizes the care planning process as the structuring framework for coordinating communication that will result in safe and effective care.The Joint Commission (n.d.). Standards and guides pertinent to nursing practice. https://www.jointcommission.org/resources/for-nurses/nursing-resources/ Many facilities have established standardized nursing care plans with lists of possible interventions that can be customized for each specific patient. Other facilities require the nurse to develop each care plan independently. Whatever the format, nursing care plans should be individualized to meet the specific and unique needs of each patient. See Figure 4.13“Figure 3-3. An example of a nursing care plan in an Australian residential aged care home..png” by NurseRecord is licensed under CC BY-SA 4.0 for an image of a standardized care plan. Nursing care plans created in nursing school can also be in various formats such as concept maps or tables. Some are fun and creative, while others are more formal. Appendix B contains a template that can be used for creating nursing care plans. 4.7 Implementation of Interventions Open Resources for Nursing (Open RN) Implementation is the fifth step of the nursing process (and the fifth Standard of Practice set by the American Nurses Association). This standard is defined as, “The registered nurse implements the identified plan.” The RN may delegate planned interventions after considering the circumstance, person, task, communication, supervision, and evaluation, as well as the state Nurse Practice Act, federal regulation, and agency policy.American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. Implementation of interventions requires the RN to use critical thinking and clinical judgment. After the initial plan of care is developed, continual reassessment of the patient is necessary to detect any changes in the patient’s condition requiring modification of the plan. The need for continual patient reassessment underscores the dynamic nature of the nursing process and is crucial to providing safe care. During the implementation phase of the nursing process, the nurse prioritizes planned interventions, assesses patient safety while implementing interventions, delegates interventions as appropriate, and documents interventions performed. Prioritizing Implementation of Interventions Prioritizing implementation of interventions follows a similar method as to prioritizing nursing diagnoses. Maslow’s Hierarchy of Needs and the ABCs of airway, breathing, and circulation are used to establish top priority interventions. When possible, least invasive actions are usually preferred due to the risk of injury from invasive options. Read more about methods for prioritization under the “Diagnosis” subsection of this chapter. The potential impact on future events, especially if a task is not completed at a certain time, is also included when prioritizing nursing interventions. For example, if a patient is scheduled to undergo a surgical procedure later in the day, the nurse prioritizes initiating a NPO (nothing by mouth) prescription prior to completing pre-op patient education about the procedure. The rationale for this decision is that if the patient ate food or drank water, the surgery time would be delayed. Knowing and understanding the patient’s purpose for care, current situation, and expected outcomes are necessary to accurately prioritize interventions. Patient Safety It is essential to consider patient safety when implementing interventions. At times, patients may experience a change in condition that makes a planned nursing intervention or provider prescription no longer safe to implement. For example, an established nursing care plan for a patient states, “The nurse will ambulate the patient 100 feet three times daily.” However, during assessment this morning, the patient reports feeling dizzy today, and their blood pressure is 90/60. Using critical thinking and clinical judgment, the nurse decides to not implement the planned intervention of ambulating the patient. This decision and supporting assessment findings should be documented in the patient’s chart and also communicated during the shift handoff report, along with appropriate notification of the provider of the patient’s change in condition. Implementing interventions goes far beyond implementing provider prescriptions and completing tasks identified on the nursing care plan and must focus on patient safety. As front-line providers, nurses are in the position to stop errors before they reach the patient.Robert Wood Johnson Foundation. (2011, April 28). Nurses are key to improving patient safety. https://www.rwjf.org/en/library/articles-and-news/2011/04/nurses-are-key-to-improving-patient-safety.html In 2000 the Institute of Medicine (IOM) issued a groundbreaking report titled To Err Is Human: Building a Safer Health System. The report stated that as many as 98,000 people die in U.S. hospitals each year as a result of preventable medical errors. To Err Is Human broke the silence that previously surrounded the consequences of medical errors and set a national agenda for reducing medical errors and improving patient safety through the design of a safer health system.Institute of Medicine (US) Committee on Quality of Health Care in America, Kohn, L. T., Corrigan, J. M., & Donaldson, M. S. (Eds.). (2000). To err is human: Building a safer health system. National Academies Press. https://pubmed.ncbi.nlm.nih.gov/25077248/ In 2007 the IOM published a follow-up report titled Preventing Medication Errors and reported that more than 1.5 million Americans are injured every year in American hospitals, and the average hospitalized patient experiences at least one medication error each day. This report emphasized actions that health care systems could take to improve medication safety.Institute of Medicine. (2007). Preventing medication errors. National Academies Press. https://doi.org/10.17226/11623. In an article released by the Robert Wood Johnson Foundation, errors involving nurses that endanger patient safety cover broad territory. This territory spans “wrong site, wrong patient, wrong procedure” errors, medication mistakes, failures to follow procedures that prevent central line bloodstream and other infections, errors that allow unsupervised patients to fall, and more. Some errors can be traced to shifts that are too long that leave nurses fatigued, some result from flawed systems that do not allow for adequate safety checks, and others are caused by interruptions to nurses while they are trying to administer medications or provide other care.Robert Wood Johnson Foundation. (2011, April 28). Nurses are key to improving patient safety. https://www.rwjf.org/en/library/articles-and-news/2011/04/nurses-are-key-to-improving-patient-safety.html The Quality and Safety Education for Nurses (QSEN) project began in 2005 to assist in preparing future nurses to continuously improve the quality and safety of the health care systems in which they work. The vision of the QSEN project is to “inspire health care professionals to put quality and safety as core values to guide their work.”QSEN Institute. (n.d.). Project overview: The evolution of the quality and safety education for nurses (QSEN) initiative. http://qsen.org/about-qsen/project-overview/ Nurses and nursing students are expected to participate in quality improvement (QI) initiatives by identifying gaps where change is needed and assisting in implementing initiatives to resolve these gaps. Quality improvement is defined as, “The combined and unceasing efforts of everyone – health care professionals, patients and their families, researchers, payers, planners and educators – to make the changes that will lead to better patient outcomes (health), better system performance (care), and better professional development (learning).”Batalden, P. B., & Davidoff, F. (2007). What is “quality improvement” and how can it transform healthcare?. BMJ Quality & Safety, 16(1), 2–3. https://doi.org/10.1136/qshc.2006.022046 Delegation of Interventions While implementing interventions, RNs may elect to delegate nursing tasks. Delegation is defined by the American Nurses Association as, “The assignment of the performance of activities or tasks related to patient care to unlicensed assistive personnel or licensed practical nurses (LPNs) while retaining accountability for the outcome.”American Nurses Association. (2013). ANA’s principles for delegation by registered nurses to unlicensed assistive personnel (UAP). American Nurses Association. https://www.nursingworld.org/~4af4f2/globalassets/docs/ana/ethics/principlesofdelegation.pdf RNs are accountable for determining the appropriateness of the delegated task according to condition of the patient and the circumstance; the communication provided to an appropriately trained LPN or UAP; the level of supervision provided; and the evaluation and documentation of the task completed. The RN must also be aware of the state Nurse Practice Act, federal regulations, and agency policy before delegating. The RN cannot delegate responsibilities requiring clinical judgment.American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. See the following box for information regarding legal requirements associated with delegation according to the Wisconsin Nurse Practice Act. Delegation According to the Wisconsin Nurse Practice Act During the supervision and direction of delegated acts a Registered Nurse shall do all of the following: (a) Delegate tasks commensurate with educational preparation and demonstrated abilities of the person supervised. (b) Provide direction and assistance to those supervised. (c) Observe and monitor the activities of those supervised. (d) Evaluate the effectiveness of acts performed under supervision.Wisconsin Administrative Code. (2018). Chapter N 6 standards of practice for registered nurses and licensed practical nurses. https://docs.legis.wisconsin.gov/code/admin_code/n/6.pdf The standard of practice for Licensed Practical Nurses in Wisconsin states, “In the performance of acts in basic patient situations, the LPN. shall, under the general supervision of an RN or the direction of a provider: (a) Accept only patient care assignments which the LPN is competent to perform. (b) Provide basic nursing care. Basic nursing care is defined as care that can be performed following a defined nursing procedure with minimal modification in which the responses of the patient to the nursing care are predictable. (c) Record nursing care given and report to the appropriate person changes in the condition of a patient. (d) Consult with a provider in cases where an LPN knows or should know a delegated act may harm a patient. (e) Perform the following other acts when applicable: - Assist with the collection of data. - Assist with the development and revision of a nursing care plan. - Reinforce the teaching provided by an RN provider and provide basic health care instruction. - Participate with other health team members in meeting basic patient needs.”Wisconsin Administrative Code. (2018). Chapter N 6 standards of practice for registered nurses and licensed practical nurses. https://docs.legis.wisconsin.gov/code/admin_code/n/6.pdf Read additional details about the scope of practice of registered nurses (RNs) and licensed practical nurses (LPNs) in Wisconsin’s Nurse Practice Act in Chapter N 6 Standards of Practice. Read more about the American Nurses Association’s Principles of Delegation. Table 4.7 outlines general guidelines for delegating nursing tasks in the state of Wisconsin according to the role of the health care team member. Table 4.7 General Guidelines for Delegating Nursing Tasks \| RN \| LPN \| CNA \| \| \|---\|---\|---\|---\| \| Assessment \| Complete patient assessment \| Assist with the collection of data for stable patients \| Collect measurements such as weight, input/output, and vital signs in stable patients \| \| Diagnosis \| Analyze assessment data and create nursing diagnoses \| Not applicable \| Not applicable \| \| Outcome Identification \| Identify SMART patient outcomes \| Not applicable \| Not applicable \| \| Planning \| Plan nursing interventions \| Assist with the development of a nursing care plan \| Not applicable \| \| Implementing Interventions \| Implement independent, dependent, and collaborative nursing interventions; delegate interventions as appropriate, with supervision \| Participate with other health team members in meeting basic patient needs Reinforce the teaching provided by an RN provider and provide basic health care instruction \| Implement and document delegated interventions associated with basic nursing care such as providing assistance in ambulating or tasks within their scope of practice \| \| Evaluation \| Evaluate the attainment of outcomes and revise the nursing care plan as needed \| Contribute data regarding the achievement of patient outcomes; assist in the revision of a nursing care plan \| Not applicable \| Documentation of Interventions As interventions are performed, they must be documented in the patient’s record in a timely manner. As previously discussed in the “Ethical and Legal Issues” subsection of the “Basic Concepts” section, lack of documentation is considered a failure to communicate and a basis for legal action. A basic rule of thumb is if an intervention is not documented, it is considered not done in a court of law. It is also important to document administration of medication and other interventions in a timely manner to prevent errors that can occur due to delayed documentation time. Coordination of Care and Health Teaching/Health Promotion ANA’s Standard of Professional Practice for Implementation also includes the standards 5A Coordination of Care and 5B Health Teaching and Health Promotion.American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. Coordination of Care includes competencies such as organizing the components of the plan, engaging the patient in self-care to achieve goals, and advocating for the delivery of dignified and holistic care by the interprofessional team. Health Teaching and Health Promotion is defined as, “Employing strategies to teach and promote health and wellness.”American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. Patient education is an important component of nursing care and should be included during every patient encounter. For example, patient education may include teaching about side effects while administering medications or teaching patients how to self-manage their conditions at home. Putting It Together Refer to Scenario C in the “Assessment” section of this chapter. The nurse implemented the nursing care plan documented in Appendix C. Interventions related to breathing were prioritized. Administration of the diuretic medication was completed first, and lung sounds were monitored frequently for the remainder of the shift. Weighing the patient before breakfast was delegated to the CNA. The patient was educated about her medications and methods to use to reduce peripheral edema at home. All interventions were documented in the electronic medical record (EMR). 4.8 Evaluation Open Resources for Nursing (Open RN) Evaluation is the sixth step of the nursing process (and the sixth Standard of Practice set by the American Nurses Association). This standard is defined as, “The registered nurse evaluates progress toward attainment of goals and outcomes.”American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. Both the patient status and the effectiveness of the nursing care must be continuously evaluated and the care plan modified as needed.American Nurses Association. (n.d.) The nursing process. https://www.nursingworld.org/practice-policy/workforce/what-is-nursing/the-nursing-process/ Evaluation focuses on the effectiveness of the nursing interventions by reviewing the expected outcomes to determine if they were met by the time frames indicated. During the evaluation phase, nurses use critical thinking to analyze reassessment data and determine if a patient’s expected outcomes have been met, partially met, or not met by the time frames established. If outcomes are not met or only partially met by the time frame indicated, the care plan should be revised. Reassessment should occur every time the nurse interacts with a patient, discusses the care plan with others on the interprofessional team, or reviews updated laboratory or diagnostic test results. Nursing care plans should be updated as higher priority goals emerge. The results of the evaluation must be documented in the patient’s medical record. Ideally, when the planned interventions are implemented, the patient will respond positively and the expected outcomes are achieved. However, when interventions do not assist in progressing the patient toward the expected outcomes, the nursing care plan must be revised to more effectively address the needs of the patient. These questions can be used as a guide when revising the nursing care plan: - Did anything unanticipated occur? - Has the patient’s condition changed? - Were the expected outcomes and their time frames realistic? - Are the nursing diagnoses accurate for this patient at this time? - Are the planned interventions appropriately focused on supporting outcome attainment? - What barriers were experienced as interventions were implemented? - Does ongoing assessment data indicate the need to revise diagnoses, outcome criteria, planned interventions, or implementation strategies? - Are different interventions required? Putting It Together Refer to Scenario C in the “Assessment” section of this chapter and Appendix C. The nurse evaluates the patient’s progress toward achieving the expected outcomes. For the nursing diagnosis Fluid Volume Excess, the nurse evaluated the four expected outcomes to determine if they were met during the time frames indicated: - The patient will report decreased dyspnea within the next 8 hours. - The patient will have clear lung sounds within the next 24 hours. - The patient will have decreased edema within the next 24 hours. - The patient’s weight will return to baseline by discharge. Evaluation of the patient condition on Day 1 included the following data: “The patient reported decreased shortness of breath, and there were no longer crackles in the lower bases of the lungs. Weight decreased by 1 kg, but 2+ edema continued in ankles and calves.” Based on this data, the nurse evaluated the expected outcomes as “Partially Met” and revised the care plan with two new interventions: - Request prescription for TED hose from provider. - Elevate patient’s legs when sitting in chair. For the second nursing diagnosis, Risk for Falls, the nurse evaluated the outcome criteria as “Met” based on the evaluation, “The patient verbalizes understanding and is appropriately calling for assistance when getting out of bed. No falls have occurred.” The nurse will continue to reassess the patient’s progress according to the care plan during hospitalization and make revisions to the care plan as needed. Evaluation of the care plan is documented in the patient’s medical record. 4.9 Summary of the Nursing Process Open Resources for Nursing (Open RN) You have now learned how to perform each step of the nursing process according to the ANA Standards of Professional Nursing Practice. Critical thinking, clinical reasoning, and clinical judgment are used when assessing the patient, creating a nursing care plan, and implementing interventions. Frequent reassessment, with revisions to the care plan as needed, is important to help the patient achieve expected outcomes. Throughout the entire nursing process, the patient always remains the cornerstone of nursing care. Providing individualized, patient-centered care and evaluating whether that care has been successful in achieving patient outcomes are essential for providing safe, professional nursing practice. Video Review of Creating a Sample Care PlanRegisteredNurseRN. (2015, June11). Nursing care plan tutorial \| How to complete a care plan in nursing school. [Video]. YouTube. All rights reserved. Video used with permission. https//youtu.be/07Z4ywfmLg8 4.10 Learning Activities Open Resources for Nursing (Open RN) Learning Activities (Answers to “Learning Activities” can be found in the “Answer Key” at the end of the book. Answers to interactive activity elements will be provided within the element as immediate feedback.) Instructions: Apply what you’ve learned in this chapter by creating a nursing care plan using the following scenario. Use the template in Appendix B as a guide. The client, Mark S., is a 57-year-old male who was admitted to the hospital with “severe” abdominal pain that was unable to be managed in the Emergency Department. The physician has informed Mark that he will need to undergo some diagnostic tests. The tests are scheduled for the morning. After receiving the news about his condition and the need for diagnostic tests, Mark begins to pace the floor. He continues to pace constantly. He keeps asking the nurse the same question (“How long will the tests take?”) about his tests over and over again. The patient also remarked, “I’m so uptight I will never be able to sleep tonight.” The nurse observes that the client avoids eye contact during their interactions and that he continually fidgets with the call light. His eyes keep darting around the room. He appears tense and has a strained expression on his face. He states, “My mouth is so dry.” The nurse observes his vital signs to be: T 98, P 104, R 30, BP 180/96. The nurse notes that his skin feels sweaty (diaphoretic) and cool to the touch. Critical Thinking Activity: - - Group (cluster) the subjective and objective data. - Create a problem-focused nursing diagnosis (hypothesis). - Develop a broad goal and then identify an expected outcome in “SMART” format. - Outline three interventions for the nursing diagnosis to meet the goal. Cite an evidence-based source. - Imagine that you implemented the interventions that you identified. Evaluate the degree to which the expected outcome was achieved: Met – Partially Met – Not Met. An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=125#h5p-60 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=125#h5p-11 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=125#h5p-12 IV Glossary Open Resources for Nursing (Open RN) Advocacy: The act or process of pleading for, supporting, or recommending a cause or course of action.American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. Art of nursing: Unconditionally acceptance of the humanity of others, respecting their need for dignity and worth, while providing compassionate, comforting care.American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. At-risk populations: Groups of people who share a characteristic that causes each member to be susceptible to a particular human response, such as demographics, health/family history, stages of growth/development, or exposure to certain events/experiences.Herdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York. Associated conditions: Medical diagnoses, injuries, procedures, medical devices, or pharmacological agents. These conditions are not independently modifiable by the nurse, but support accuracy in nursing diagnosis.Herdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York. Basic nursing care: Care that can be performed following a defined nursing procedure with minimal modification in which the responses of the patient to the nursing care are predictable.Wisconsin Administrative Code. (2018). Chapter N 6 standards of practice for registered nurses and licensed practical nurses. https://docs.legis.wisconsin.gov/code/admin_code/n/6.pdf Caring relationship: A relationship described as one in which the whole person is assessed while balancing the vulnerability and dignity of the patient and family.Walivaara, B., Savenstedt, S., & Axelsson, K. (2013). Caring relationships in home-based nursing care – registered nurses’ experiences. The Open Journal of Nursing, 7, 89-95. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3722540/pdf/TONURSJ-7-89.pdf Client: Individual, family, or group, which includes significant others and populations.NCSBN. (n.d.). 2019 NCLEX-RN test plan. https://www.ncsbn.org/2019_RN_TestPlan-English.htm Clinical judgment: The observed outcome of critical thinking and decision-making. It is an iterative process that uses nursing knowledge to observe and access presenting situations, identify a prioritized client concern, and generate the best possible evidence-based solutions in order to deliver safe client care.NCSBN. (n.d.). NCSBN clinical judgment model. https://www.ncsbn.org/14798.htm Clinical reasoning: A complex cognitive process that uses formal and informal thinking strategies to gather and analyze patient information, evaluate the significance of this information, and weigh alternative actions. Klenke-Borgmann, L., Cantrell, M. A., & Mariani, B. (2020). Nurse educator’s guide to clinical judgment: A review of conceptualization, measurement, and development. Nursing Education Perspectives, 41(4), 215-221. Clustering data: Grouping data into similar domains or patterns. Collaborative nursing interventions: Nursing interventions that require cooperation among health care professionals and unlicensed assistive personnel (UAP). Coordination of care: While implementing interventions during the nursing process, includes components such as organizing the components of the plan with input from the health care consumer, engaging the patient in self-care to achieve goals, and advocating for the delivery of dignified and person-centered care by the interprofessional team.American Nurses Association. (2021). Nursing: Scope and standards of practice (3rd ed.). American Nurses Association. Critical thinking: Reasoning about clinical issues such as teamwork, collaboration, and streamlining workflow.Klenke-Borgmann, L., Cantrell, M. A. , & Mariani, B. (2020). Nurse educator’s guide to clinical judgment: A review of conceptualization, measurement, and development. Nursing Education Perspectives, 41(4), 215-221. Cue: Subjective or objective data that gives the nurse a hint or indication of a potential problem, process, or disorder. Deductive reasoning: “Top-down thinking” or moving from the general to the specific. Deductive reasoning relies on a general statement or hypothesis—sometimes called a premise or standard—that is held to be true. The premise is used to reach a specific, logical conclusion. Defining characteristics: Observable cues/inferences that cluster as manifestations of a problem-focused, health-promotion diagnosis, or syndrome. This does not only imply those things that the nurse can see, but also things that are seen, heard (e.g., the patient/family tells us), touched, or smelled.NANDA International. (n.d.). Glossary of terms. https://nanda.org/nanda-i-resources/glossary-of-terms/ Delegation: The assignment of the performance of activities or tasks related to patient care to unlicensed assistive personnel while retaining accountability for the outcome.American Nurses Association. (2013). ANA’s principles for delegation by registered nurses to unlicensed assistive personnel (UAP). American Nurses Association. https://www.nursingworld.org/~4af4f2/globalassets/docs/ana/ethics/principlesofdelegation.pdf Dependent nursing interventions: Interventions that require a prescription from a physician, advanced practice nurse, or physician’s assistant. Direct care: Interventions that are carried out by having personal contact with a patient. Electronic Medical Record (EMR): An electronic version of the patient’s medical record. Evidence-Based Practice (EBP): A lifelong problem-solving approach that integrates the best evidence from well-designed research studies and evidence-based theories; clinical expertise and evidence from assessment of the health care consumer’s history and condition, as well as health care resources; and patient, family, group, community, and population preferences and values.American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. Expected outcomes: Statements of measurable action for the patient within a specific time frame and in response to nursing interventions. “SMART” outcome statements are specific, measurable, action-oriented, realistic, and include a time frame. Functional health patterns: An evidence-based assessment framework for identifying patient problems and risks during the assessment phase of the nursing process. Generalization: A judgment formed from a set of facts, cues, and observations. Goals: Broad statements of purpose that describe the aim of nursing care. Health teaching and health promotion: Employing strategies to teach and promote health and wellness.American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. Independent nursing interventions: Any intervention that the nurse can provide without obtaining a prescription or consulting anyone else. Indirect care: Interventions performed by the nurse in a setting other than directly with the patient. An example of indirect care is creating a nursing care plan. Inductive reasoning: A type of reasoning that involves forming generalizations based on specific incidents. Inference: Interpretations or conclusions based on cues, personal experiences, preferences, or generalizations. Licensed Practical Nurses or Licensed Vocational Nurses (LPNs/LVNs): Nurses who have had specific training and passed a licensing exam. The training is generally less than that of a Registered Nurse. The scope of practice of an LPN/LVN is determined by the facility and the state’s Nurse Practice Act. Medical diagnosis: A disease or illness diagnosed by a physician or advanced health care provider such as a nurse practitioner or physician’s assistant. Medical diagnoses are a result of clustering signs and symptoms to determine what is medically affecting an individual. Nursing: Nursing integrates the art and science of caring and focuses on the protection, promotion, and optimization of health and human functioning; prevention of illness and injury; facilitation of healing; and alleviation of suffering through compassionate presence. Nursing is the diagnosis and treatment of human responses and advocacy in the care of individuals, families, groups, communities, and populations in the recognition of the connection of all humanity.American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. Nursing care plan: Specific documentation of the planning and delivery of nursing care that is required by The Joint Commission. Nursing process: A systematic approach to patient-centered care with steps including assessment, diagnosis, outcome identification, planning, implementation, and evaluation; otherwise known by the mnemonic “ADOPIE.” Objective data: Data that the nurse can see, touch, smell, or hear or is reproducible such as vital signs. Laboratory and diagnostic results are also considered objective data. Outcome: A measurable behavior demonstrated by the patient that is responsive to nursing interventions.Herdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York. PES Statement: The format of a nursing diagnosis statement that includes: - Problem (P) – statement of the patient problem (i.e., the nursing diagnosis) - Etiology (E) – related factors (etiology) contributing to the cause of the nursing diagnosis - Signs and Symptoms (S) – defining characteristics manifested by the patient of that nursing diagnosis Prescription: Orders, interventions, remedies, or treatments ordered or directed by an authorized primary health care provider.NCSBN. (n.d.). 2019 NCLEX-RN test plan. https://www.ncsbn.org/2019_RN_TestPlan-English.htm Primary data: Information collected from the patient. Primary health care provider: Member of the health care team (usually a medical physician, nurse practitioner, etc.) licensed and authorized to formulate prescriptions on behalf of the client.NCSBN. (n.d.). 2019 NCLEX-RN test plan. https://www.ncsbn.org/2019_RN_TestPlan-English.htm Prioritization: The skillful process of deciding which actions to complete first, second, or third for optimal patient outcomes and to improve patient safety. Quality improvement: The “combined and unceasing efforts of everyone — health care professionals, patients and their families, researchers, payers, planners, and educators — to make the changes that will lead to better patient outcomes (health), better system performance (care), and better professional development (learning).”Batalden, P. B., & Davidoff, F. (2007). What is “quality improvement” and how can it transform healthcare?. BMJ Quality & Safety, 16(1), 2–3. https://doi.org/10.1136/qshc.2006.022046 Rapport: Developing a relationship of mutual trust and understanding. Registered Nurse (RN): A nurse who has had a designated amount of education and training in nursing and is licensed by a state Board of Nursing. Related factors: The underlying cause (etiology) of a nursing diagnosis when creating a PES statement. Right to self-determination: Patients have the right to determine what will be done with and to their own person. Scientific method: Principles and procedures in the discovery of knowledge involving the recognition and formulation of a problem, the collection of data, and the formulation and testing of a hypothesis. Secondary data: Information collected from sources other than the patient. Subjective data: Data that the patient or family reports or data that the nurse makes as an inference, conclusion, or assumption, such as “The patient appears anxious.” Unlicensed Assistive Personnel (UAP): Any unlicensed personnel trained to function in a supportive role, regardless of title, to whom a nursing responsibility may be delegated.NCSBN. (n.d.). 2019 NCLEX-RN test plan. https://www.ncsbn.org/2019_RN_TestPlan-English.htm Safety V 5.1 Safety Introduction Open Resources for Nursing (Open RN) Learning Objectives - Indicate correct identification of patient prior to performing any patient care measures - Identify safety considerations for adults of all ages - Include industry standards and regulations regarding microbiological, physical, and environmental safety - Apply decision-making related to measures to minimize use of restraints - Identify evidence-based practices A national focus on reducing medical errors has been in place since 1999 when the Institute of Medicine (IOM) released a report titled To Err is Human: Building a Safer Health System. This historic report broke the silence surrounding health care errors and encouraged safety to be built into the processes of providing patient care. It was soon followed by the establishment of several safety initiatives by The Joint Commission, including the release of annual National Patient Safety Goals. Additionally, the Quality and Safety Education for Nurses (QSEN) Institute was developed to promote emphasis on high-quality, safe patient care in nursing. This chapter will discuss several safety initiatives that promote a safe health care environment. 5.2 Basic Safety Concepts Open Resources for Nursing (Open RN) Safety: A Basic Need Safety is a basic foundational human need and always receives priority in patient care. Nurses typically use Maslow’s Hierarchy of Needs to prioritize urgent patient needs, with the bottom two rows of the pyramid receiving top priority. See Figure 5.1“Maslow’s hierarchy of needs.svg” by J. Finkelstein is licensed under CC BY-SA 3.0 for an image of Maslow’s Hierarchy of Needs. Safety is intertwined with basic physiological needs. Consider the following scenario: You are driving back from a relaxing weekend at the lake and come upon a fiery car crash. You run over to the car to help anyone inside. When you get to the scene, you notice that the lone person in the car is not breathing. Your first priority is not to initiate rescue breathing inside the burning car, but to move the person to a safe place where you can safely provide CPR. In nursing, the concept of patient safety is central to everything we do in all health care settings. As a nurse, you play a critical role in promoting patient safety while providing care. You also teach patients and their caregivers how to prevent injuries and remain safe in their homes and in the community. Safe patient care also includes measures to keep you safe in the health care environment; if you become ill or injured, you will not be able to effectively care for others. Safe patient care is a commitment to providing the best possible care to every patient and their caregivers in every moment of every day. Patients come to health care facilities expecting to be kept safe while they are treated for illnesses and injuries. Unfortunately, you may have heard stories about situations when that did not happen. Medical errors can be devastating to patients and their families. Consider the true patient story in the following box that illustrates factors affecting patient safety. The Josie King Story In 2001, 18-month-old Josie King died as a result of medical errors in a well-known hospital from a hospital-acquired infection and a wrongly administered pain medication. How did this preventable death happen? Watch this video of her mother, Sorrel King, telling Josie’s story and explaining how Josie’s death spurred her work on improving patient safety in hospitals everywhere.Healthcare.gov. (2011, May 25). Introducing the partnerships for patients with Sorrel King. [Video]. YouTube. https://youtu.be/ak_5X66V5Ms Reflective Questions: - What factors contributed to Josie’s death? - How could these factors be resolved? Never Events The event described in the Josie King story is considered a “never event.” Never events are adverse events that are clearly identifiable, measurable, serious (resulting in death or significant disability), and preventable. In 2007 the Centers for Medicare and Medicaid Services (CMS) discontinued payment for costs associated with never events, and this policy has been adopted by most private insurance companies. Never events are publicly reported, with the goal of increasing accountability by health care agencies and improving the quality of patient care. The current list of never events includes seven categories of events: - Surgical or procedural event, such as surgery performed on the wrong body part - Product or device, such as injury or death from a contaminated drug or device - Patient protection, such as patient suicide in a health care setting - Care management, such as death or injury from a medication error - Environmental, such as death or injury as the result of using restraints - Radiologic, such as a metallic object in an MRI area - Criminal, such as death or injury of a patient or staff member resulting from physical assault on the grounds of a health care setting Sentinel Events Sentinel events are similar to never events but are not necessarily preventable. They are defined as an “unexpected occurrence involving death or serious physiological or psychological injury, or the risk thereof.” For example, injury or death from a properly prescribed and administered medication is a sentinel event. The Joint Commission mandates reporting of sentinel events and the performance of a root cause analysis by the health care agency. Root cause analysis is a structured method used to analyze serious adverse events to identify underlying problems that increase the likelihood of errors, while avoiding the trap of focusing on mistakes by individuals. A multidisciplinary team analyzes the sequence of events leading up to the error with the goal of identifying how and why the event occurred. The ultimate goal of root cause analysis is to prevent future harm by eliminating hidden problems within a health care system that contribute to adverse events. For example, when a medication error occurs, a root cause analysis goes beyond focusing on the mistake by the nurse and looks at other system factors that contributed to the error, such as similar-looking drug labels, placement of similar-looking medications next to each other in a medication dispensing machine, or vague instructions in a provider order. Root cause analysis uses human factors science as part of the investigation. Human factors focus on the interrelationships among humans, the tools and equipment they use in the workplace, and the environment in which they work. Safety in health care is ultimately dependent on humans – the doctors, nurses, and health care professionals – providing the care. Near Misses In addition to investigating sentinel events and never events, agencies use root cause analysis to investigate near misses. Near misses are defined by the World Health Organization (WHO) as, “An error that has the potential to cause an adverse event (patient harm) but fails to do so because of chance or because it is intercepted.” Errors and near misses are rarely the result of poor motivation or incompetence of the health care professional, but are often caused by key contributing factors such as poor communication, less-than-optimal teamwork, memory overload, reliance on memory for complex procedures, and lack of standardization of policies and procedures. In an effort to prevent near misses, medical errors, sentinel events, and never events, several safety strategies have been developed and implemented in health care organizations across the country. These strategies will be discussed throughout the remainder of the chapter. 5.3 Safety Strategies Open Resources for Nursing (Open RN) Safety strategies have been developed based on research to reduce the likelihood of errors and to create safe standards of care. Examples of safety initiatives include strategies to prevent medication errors, standardized checklists, and structured team communication tools. Medication Errors Several initiatives have been developed nationally to prevent medication errors, such as the establishment of a “Do Not Use List of Abbreviations,” a “List of Error-Prone Abbreviations,” “Frequently Confused Medication List,” “High-Alert Medications List,” and the “Do Not Crush List.” Additionally, it is considered a standard of care for nurses to perform three checks of the rights of medication administration whenever administering medication. View more information about these safety initiatives to prevent medication errors using the hyperlinks provided below. Specific strategies to prevent medication errors are discussed in the “Preventing Medication Errors” of the “Legal/Ethical” chapter of the Open RN Nursing Pharmacology textbook. The rights of medication administration are discussed in the “Basic Concepts of Administering Medications” section of the “Administration of Enteral Medications” chapter of the Open RN Nursing Skills textbook. Read more about safety initiatives implemented to prevent medication errors using these hyperlinks: Checklists Performance of complex medical procedures is often based on memory, even though humans are prone to short-term memory loss, especially when we are multitasking or under stress. The point-of-care checklist is an example of a patient care safety initiative that reduces this reliance on fallible memory. For example, a surgical checklist developed by the World Health Organization (WHO) has been adopted by most surgical providers around the world as a standard of care. It has significantly decreased injuries and deaths caused by surgeries by focusing on teamwork and communication. The Association of PeriOperative Registered Nurses (AORN) combined recommendations from The Joint Commission and the WHO to create a specific surgical checklist for nurses. See Figure 5.2“9789241598590_eng_Checklist.pdf” by WHO is in the Public Domain for an image of the WHO surgical checklist. Review the AORN Comprehensive Surgical Checklist by the Association of PeriOperative Registered Nurses. Team Communication Nurses routinely communicate with multidisciplinary health care team members and contact health care providers to report changes in patient status. Serious patient harm can occur when patient information is absent, incomplete, erroneous, or delayed during team communication. Standardized methods of communication have been developed to ensure that accurate information is exchanged among team members in a structured and concise manner. ISBARR A common format for communication between health care team members is ISBARR, a mnemonic for the components of Introduction, Situation, Background, Assessment, Request/Recommendations, and Repeat back. See Figure 5.3“ISBARR Reference Card” by Kim Ernstmeyer at Chippewa Valley Technical College is licensed under CC BY 4.0 for an image of an ISBARR reference card. - Introduction: Introduce your name, role, and the agency from which you are calling. - Situation: Provide the patient’s name and location, why you are calling, recent vital signs, and the status of the patient. - Background: Provide pertinent background information about the patient such as admitting medical diagnoses, code status, recent relevant lab or diagnostic results, and allergies. - Assessment: Share abnormal assessment findings and your concerns. - Request/Recommendations: State what you would like the provider to do, such as reassess the patient, order a lab/diagnostic test, prescribe/change medication, etc. - Repeat back: If you are receiving new orders from a provider, repeat them to confirm accuracy. Be sure to document communication with the provider in the patient’s chart. Handoff Reports Handoff reports are a specific type of team communication as patient care is transferred. Handoff reports are defined by The Joint Commission as, “A transfer and acceptance of patient care responsibility achieved through effective communication. It is a real-time process of passing patient specific information from one caregiver to another, or from one team of caregivers to another, for the purpose of ensuring the continuity and safety of the patient’s care.” Handoff reports occur during multiple stages of patient care, such as between nurses at the end of shifts, when a patient is transferred from one unit to another within a health care agency, or when a patient is transferred to a different facility. In 2017 The Joint Commission issued a sentinel alert about inadequate handoff communication resulting in patient harm such as wrong-site surgeries, delays in treatment, falls, and medication errors. Strategies to improve handoff communication, such as bedside handoff report checklists, have been implemented at agencies across the country. Bedside handoff reports typically occur between nurses during inpatient care as the off-going and the incoming nurses communicate current, up-to-date details about the patient’s care . The report is optimally conducted at the bedside and includes the patient. Family members may be included during the report with the patient’s permission. See the hyperlink below to view a sample bedside shift report checklist from the Agency for Healthcare Research and Quality. Although a bedside handoff report is similar to an ISBARR report, it contains additional information to ensure continuity of care across nursing shifts, such as current head-to-toe assessment findings to establish baseline status; information about equipment such as IVs, catheters, and drainage tubes; and recent changes in medications, lab results, diagnostic tests, and treatments. View a Bedside Shift Report Checklist from the Agency for Healthcare Research and Quality. 5.4 Culture of Safety Open Resources for Nursing (Open RN) In addition to implementing safety strategies to improve safe patient care, leaders of a health care agency must also establish a culture of safety. A culture of safety reflects the behaviors, beliefs, and values within and across all levels of an organization as they relate to safety and clinical excellence, with a focus on people. In 2017 The Joint Commission released a sentinel event regarding the essential role of leadership in establishing a culture of safety. Three components of a culture of safety are the following: - Just Culture: A culture where people feel safe raising questions and concerns and report safety events in an environment that emphasizes a nonpunitive response to errors and near misses. Clear lines are drawn between human error, at-risk, and reckless behaviors. - Reporting Culture: People realize errors are inevitable and are encouraged to speak up for patient safety by reporting errors and near misses. - Learning Culture: People regularly collect information and learn from errors and successes while openly sharing data and information and applying best evidence to improve work processes and patient outcomes. The American Nurses Association further describes a culture of safety as one that includes openness and mutual respect when discussing safety concerns and solutions without shifting to individual blame, a learning environment with transparency and accountability, and reliable teams. In contrast, complexity, lack of clear measures, hierarchical authority, the “blame game,” and lack of leadership are examples of barriers that do not promote a culture of safety. See the following box for an example of safety themes established during a health care institution’s implementation of a culture of safety. Safety Themes in a Culture of SafetyInstitute of Medicine (US) Committee on the Work Environment for Nurses and Patient Safety. (2004). Creating and sustaining a culture of safety. In Keeping patients safe: Transforming the work environment of nurses. National Academies Press. https://www.ncbi.nlm.nih.gov/books/NBK216181 Kaiser Permantente implemented a culture of safety in 2001 that focused on instituting the following six strategic themes: - Safe culture: Creating and maintaining a strong patient safety culture, with patient safety and error reduction embraced as shared organizational values. - Safe care: Ensuring that the actual and potential hazards associated with high-risk procedures, processes, and patient care populations are identified, assessed, and managed in a way that demonstrates continuous improvement and ultimately ensures that patients are free from accidental injury or illness. - Safe staff: Ensuring that staff possess the knowledge and competence to perform required duties safely and contribute to improving system safety performance. - Safe support systems: Identifying, implementing, and maintaining support systems—including knowledge-sharing networks and systems for responsible reporting—that provide the right information to the right people at the right time. - Safe place: Designing, constructing, operating, and maintaining the environment of health care to enhance its efficiency and effectiveness. - Safe patients: Engaging patients and their families in reducing medical errors, improving overall system safety performance, and maintaining trust and respect. A strong safety culture encourages all members of the health care team to identify and reduce risks to patient safety by reporting errors and near misses so that root cause analysis can be performed and identified risks are removed from the system. However, in a poorly defined and implemented culture of safety, staff often conceal errors due to fear or shame. Nurses have been traditionally trained to believe that clinical perfection is attainable and that “good” nurses do not make errors. Errors are perceived as being caused by carelessness, inattention, indifference, or uninformed decisions. Although expecting high standards of performance is appropriate and desirable, it can become counterproductive if it creates an expectation of perfection that impacts the reporting of errors and near misses. If employees feel shame when they make an error, they may feel pressure to hide or cover up errors. Evidence indicates that approximately three of every four errors are detected by those committing them, as opposed to being detected by an environmental cue or another person. Therefore, employees need to be able to trust that they can fully report errors without fear of being wrongfully blamed. This provides the agency with the opportunity to learn how to further improve processes and prevent future errors from occurring. For many organizations, the largest barrier in establishing a culture of safety is the establishment of trust. A model called “Just Culture” has successfully been implemented in many agencies to decrease the “blame game,” promote trust, and improve the reporting of errors. Just Culture The American Nurses Association (ANA) officially endorses the Just Culture model. In 2019 the ANA published a position statement on Just Culture, stating, “Traditionally, healthcare’s culture has held individuals accountable for all errors or mishaps that befall patients under their care. By contrast, a Just Culture recognizes that individual practitioners should not be held accountable for system failings over which they have no control. A Just Culture also recognizes many individual or ‘active’ errors represent predictable interactions between human operators and the systems in which they work. However, in contrast to a culture that touts ‘no blame’ as its governing principle, a Just Culture does not tolerate conscious disregard of clear risks to patients or gross misconduct (e.g., falsifying a record or performing professional duties while intoxicated).” The Just Culture model categorizes human behavior into three causes of errors. Consequences of errors are based on whether the error is a simple human error or caused by at-risk or reckless behavior. - Simple human error: A simple human error occurs when an individual inadvertently does something other than what should have been done. Most medical errors are the result of human error due to poor processes, programs, education, environmental issues, or situations. These errors are managed by correcting the cause, looking at the process, and fixing the deviation. For example, a nurse appropriately checks the rights of medication administration three times, but due to the similar appearance and names of two different medications stored next to each other in the medication dispensing system, administers the incorrect medication to a patient. In this example, a root cause analysis reveals a system issue that must be modified to prevent future patient errors (e.g., change the labelling and storage of look alike-sound alike medication). - At-risk behavior: An error due to at-risk behavior occurs when a behavioral choice is made that increases risk where the risk is not recognized or is mistakenly believed to be justified. For example, a nurse scans a patient’s medication with a bar code scanner prior to administration, but an error message appears on the scanner. The nurse mistakenly interprets the error to be a technology problem and proceeds to administer the medication instead of stopping the process and further investigating the error message, resulting in the wrong dosage of a medication being administered to the patient. In this case, ignoring the error message on the scanner can be considered “at-risk behavior” because the behavioral choice was considered justified by the nurse at the time. - Reckless behavior: Reckless behavior is an error that occurs when an action is taken with conscious disregard for a substantial and unjustifiable risk.American Nursing Association. (2010). Position statement: Just culture. https://www.nursingworld.org/~4afe07/globalassets/practiceandpolicy/health-and-safety/just_culture.pdf For example, a nurse arrives at work intoxicated and administers the wrong medication to the wrong patient. This error is considered due to reckless behavior because the decision to arrive intoxicated was made with conscious disregard for substantial risk. These examples show three different causes of medication errors that would result in different consequences to the employee based on the Just Culture model. Under the Just Culture model, after root cause analysis is completed, system-wide changes are made to decrease factors that contributed to the error. Managers appropriately hold individuals accountable for errors if they were due to simple human error, at-risk behavior, or reckless behaviors. If an individual commits a simple human error, managers console the individual and consider changes in training, procedures, and processes. In the “simple human error” above, system-wide changes would be made to change the label and location of the medication to prevent future errors from occurring with the same medication. Individuals committing at-risk behavior are held accountable for their behavioral choice and often require coaching with incentives for less risky behaviors and situational awareness. In the “at-risk behavior” example above where the nurse ignored an error message on the bar code scanner, mandatory training on using a bar code scanner and responding to errors would be implemented, and the manager would track the employee’s correct usage of the bar code scanner for several months following training. If an individual demonstrates reckless behavior, remedial action and/or punitive action is taken.American Nursing Association. (2010). Position statement: Just culture. https://www.nursingworld.org/~4afe07/globalassets/practiceandpolicy/health-and-safety/just_culture.pdfIn the “reckless behavior” example above, the manager would report the nurse’s behavior to the state’s Board of Nursing with mandatory substance abuse counseling to maintain their nursing license. Employment may be terminated with consideration of patterns of behavior. A Just Culture in which employees aren’t afraid to report errors is a highly successful way to enhance patient safety, increase staff and patient satisfaction, and improve outcomes. Success is achieved through good communication, effective management of resources, and an openness to changing processes to ensure the safety of patients and employees. The infographic in Figure 5.4 “Just Culture Infographic.png” by Valeria Palarski 2020. Used with permission.illustrates the components of a culture of safety and Just Culture. The principles of culture of safety, including Just Culture, Reporting Culture, and Learning Culture are also being adopted in nursing education. It’s understood that mistakes are part of learning and that a shared accountability model promotes individual- and system-level learning for improved patient safety. Under a shared accountability model, students are responsible for the following: - being fully prepared for clinical experiences, including laboratory and simulation assignments - being rested and mentally ready for a challenging learning environment - accepting accountability for their part in contributing to a safe learning environment - behaving professionally - reporting their own errors and near mistakes - keeping up-to-date with current evidence-based practice - adhering to ethical and legal standardsBarnsteiner, J., & Disch, J. (2017). Creating a fair and just culture in schools of nursing. American Journal of Nursing, 117(11). https://www.ncsbn.org/Barnsteiner_Creating_a_fair_and_just_culture_in_schools_of_nursing.pdf Students know they will be held accountable for their actions, but will not be blamed for system faults that lie beyond their control. They can trust that a fair process will be used to determine what went wrong if a patient care error or near miss occurs. Student errors and near misses are addressed based on an investigation determining if it was simple human error, an at-risk behavior, or reckless behavior. For example, a simple human error by a student can be addressed with coaching and additional learning opportunities to remedy the knowledge deficit. However, if a student acts with recklessness (for example, repeatedly arrives to clinical unprepared despite previous faculty feedback or falsely documents an assessment or procedure), they are appropriately and fairly disciplined, which may include dismissal from the program.Barnsteiner, J., & Disch, J. (2017). Creating a fair and just culture in schools of nursing. American Journal of Nursing, 117(11). https://www.ncsbn.org/Barnsteiner_Creating_a_fair_and_just_culture_in_schools_of_nursing.pdf 5.5 National Patient Safety Goals Open Resources for Nursing (Open RN) Every year, national patient safety goals are published by The Joint Commission to improve patient safety.National Patient Safety Goals are goals and recommendations tailored to seven different types of health care agencies based on patient safety data from experts and stakeholders. The seven health care areas include ambulatory health care settings, behavioral health care settings, critical access hospitals, home care, hospital settings, laboratories, nursing care centers, and office-based surgery settings. These goals are updated annually based on safety data and include evidence-based interventions. It is important for nurses and nursing students to be aware of the current National Patient Safety Goals for the settings in which they provide patient care and use the associated recommendations. The National Patient Safety Goals for nursing care settings (otherwise known as long-term care centers) are described in Table 5.5. (Note that the term “bedsore” is used in the last goal. This is a historic term for the current term “pressure injuries.”) Table 5.5 National Patient Safety Goals for Nursing Care CentersThe Joint Commission. (n.d.). 2021 National patient safety goals. https://www.jointcommission.org/standards/national-patient-safety-goals/ \| Goal \| Recommendations and Rationale \| \|---\|---\| \| Identify residents correctly \| Use at least two ways to identify patients or residents. For example, use the patient’s or resident’s name and date of birth. This is done to make sure that each patient or resident gets the correct medicine and treatment. \| \| Use medicines safely \| Take extra care with patients and residents who take medications to thin their blood. Record and pass along correct information about a patient’s or resident’s medications. Find out what medications the patient or resident is taking. Compare those medications to new medications given to the patient or resident. Give the patient or resident written information about the medications they need to take. Tell the patient or resident it is important to bring their up-to-date list of medications every time they visit a doctor. \| \| Prevent infection \| Use the hand hygiene guidelines from the Centers for Disease Control and Prevention or the World Health Organization. Set goals for improving hand cleaning. \| \| Prevent residents from falling \| Find out which patients and residents are most likely to fall. For example, is the patient or resident taking any medicines that might make them weak, dizzy, or sleepy? Take action to prevent falls for these patients and residents. \| \| Prevent bed sores \| Find out which patients and residents are most likely to have pressure injuries. Take action to prevent pressure injuries in these patients and residents. Per agency protocol, recheck patients and residents frequently for pressure injuries. \| Read more about National Patient Safety Goals established by The Joint Commission. Read more details about how to identify patients correctly, administer medications safely, and prevent infection by visiting the following sections in Open RN Nursing Skills: - Initiating Patient Interaction - Aseptic Technique Basic Concepts - Basic Concepts of Administering Medications Read more about “Pressure Injuries” (the newest term used for bed sores) in the “Integumentary” chapter of this book. 5.6 Preventing Falls Open Resources for Nursing (Open RN) “Prevent residents from falling” is one of the National Patient Safety Goals for nursing care centers. Patient falls, whether in the nursing care center, home, or hospital, are very common and can cause serious injury and death. Older adults have the highest risk of falling. Each year, 3 million older people are treated in emergency departments for fall injuries, and over 800,000 patients a year are hospitalized because of a head injury or hip fracture resulting from a fall. Many older adults who fall, even if they’re not injured, become afraid of falling. This fear may cause them to limit their everyday activities. However, when a person is less active, they become weaker, which further increases their chances of falling.Centers for Disease Control and Prevention. (2020, October 8). Older adult fall prevention. https://www.cdc.gov/falls/index.html Many conditions contribute to patient falls, including the following:Centers for Disease Control and Prevention. (2020, October 8). Older adult fall prevention. https://www.cdc.gov/falls/index.html - Lower body weakness - Vitamin D deficiency - Difficulties with walking and balance - Medications, such as tranquilizers, sedatives, antihypertensives, or antidepressants - Vision problems - Foot pain or poor footwear - Environmental hazards, such as throw rugs or clutter that can cause tripping Most falls are caused by a combination of risk factors. The more risk factors a person has, the greater their chances of falling. Many risk factors can be changed or modified to help prevent falls. The Centers for Disease Control has developed a program called “STEADI – Stopping Elderly Accidents, Deaths & Injuries” to help reduce the risk of older adults from falling at home. Three screening questions to determine risk for falls are as follows: - Do you feel unsteady when standing or walking? - Do you have worries about falling? - Have you fallen in the past year? If yes, how many times? Were you injured? If the individual answers “Yes” to any of these questions, further assessment of risk factors is performed.Centers for Disease Control and Prevention. (2020, October 16). STEADI – Older adult fall prevention. https://www.cdc.gov/steadi/index.html Read more information about preventing falls in older adults at CDC’s Older Adult Fall Prevention. Fall Assessment Tools By virtue of being ill, all hospitalized patients are at risk for falls, but some patients are at higher risk than others. Assessment is an ongoing process with the goal of identifying a patient’s specific risk factors and implementing interventions in their care plan to decrease their risk of falling. Commonly used fall assessment tools used to identify patients at high risk for falls are the Morse Fall Scale and the Hendrich II Fall Risk Model. Read more about these fall risk assessment tools using the hyperlinks provided below. Key risk factors for falls in hospitalized patients are as follows:Agency for Healthcare Research and Quality. (2018, July). Preventing falls in hospitals. https://www.ahrq.gov/patient-safety/settings/hospital/fall-prevention/toolkit/index.html - History of falls: All patients with a recent history of falls, such as a fall in the past three months, should be considered at higher risk for future falls. - Mobility problems and use of assistive devices: Patients who have problems with their gait or require an assistive device (such as a cane or a walker) for mobility are more likely to fall. - Medications: Patients on a large number of prescription medications or patients taking medicines that could cause sedation, confusion, impaired balance, or orthostatic blood pressure changes are at higher risk for falls. - Mental status: Patients with delirium, dementia, or psychosis may be agitated and confused, putting them at risk for falls. - Incontinence: Patients who have urinary frequency or who have frequent toileting needs are at higher fall risk. - Equipment: Patients who are tethered to equipment such as an IV pole or a Foley catheter are at higher risk of tripping. - Impaired vision: Patients with impaired vision or those who require glasses but who are not wearing them are at a higher fall risk because of their decreased recognition of an environmental hazard. - Orthostatic hypotension: Patients whose blood pressure drops upon standing often experience light-headedness or dizziness that can cause falls.Agency for Healthcare Research and Quality. (2018, July). Preventing falls in hospitals. https://www.ahrq.gov/patient-safety/settings/hospital/fall-prevention/toolkit/index.html View common fall risk assessment tools using the following hyperlinks: - Morse Fall Scale Agency for Healthcare Research and Quality. (2021, March). Preventing falls in hospitals: Tool 3H: Morse Fall Scale for identifying fall risk factors. https://www.ahrq.gov/patient-safety/settings/hospital/fall-prevention/toolkit/morse-fall-scale.html - Hendrich II Fall Risk ModelThe Hartford Institute for Geriatric Nursing, New York University, Rory Meyers School of Nursing. (n.d.). Assessment tools for best practices of care for older adults. https://hign.org/consultgeri-resources/try-this-series Interventions to Prevent Falls Universal fall precautions are established for all patients to reduce their risk for falling. In addition to universal fall precautions, a care plan is created based on the patient’s fall risk assessment findings to address their specific risks and needs. Universal Fall Precautions Falls are the most commonly reported patient safety incidents in the acute care setting. Hospitals pose an inherent fall risk due to the unfamiliarity of the environment and various hazards in the hospital room that pose a risk. During inpatient care, nurses assess their patients’ risk for falling during every shift and implement interventions to reduce the risk of falling. Universal fall precautions have been developed that apply to all patients all the time. Universal fall precautions are called “universal” because they apply to all patients, regardless of fall risk, and revolve around keeping the patient’s environment safe and comfortable.Agency for Healthcare Research and Quality. (2018, July). Preventing falls in hospitals. https://www.ahrq.gov/patient-safety/settings/hospital/fall-prevention/toolkit/index.html Universal fall precautions include the following: - Familiarize the patient with the environment. - Have the patient demonstrate call light use. - Maintain the call light within reach. See Figure 5.5“Hill-Rom_hospital_bed_TV_remote_control.JPG” by BrokenSphere is licensed under CC BY-SA 3.0. for an image of a call light. - Keep the patient’s personal possessions within safe reach. - Have sturdy handrails in patient bathrooms, rooms, and hallways. - Place the hospital bed in the low position when a patient is resting. Raise the bed to a comfortable height when the patient is transferring out of bed. - Keep the hospital bed brakes locked. - Keep wheelchair wheels in a “locked” position when stationary. - Keep no-slip, comfortable, and well-fitting footwear on the patient. - Use night lights or supplemental lighting. - Keep floor surfaces clean and dry. Clean up all spills promptly. - Keep patient care areas uncluttered. - Follow safe patient handling practices.Agency for Healthcare Research and Quality. (2018, July). Preventing falls in hospitals. https://www.ahrq.gov/patient-safety/settings/hospital/fall-prevention/toolkit/index.html Interventions Based on Risk Factors Patients at elevated risk for falling require multiple, individualized interventions, in addition to universal fall precautions. There are many interventions available to prevent falls and fall-related injuries based on the patient’s specific risk factors. See Table 5.6a for interventions categorized by risk factor.Agency for Healthcare Research and Quality. (2018, July). Preventing falls in hospitals. https://www.ahrq.gov/patient-safety/settings/hospital/fall-prevention/toolkit/index.html Table 5.6a Interventions Based on Fall Risk Factors \| Risk Factor \| Interventions \| \|---\|---\| \| Altered Mental Status \| Patients with new altered mental status should be assessed for delirium and treated by a trained nurse or physician. See a tool for assessing delirium in the hyperlink below. For cognitively impaired patients who are agitated or trying to wander, more intense supervision (e.g., sitter or checks every 15 minutes) may be needed. Some hospitals implement designated safety zones that include low beds, mats for each side of the bed, nightlight, gait belt, and a “STOP” sign to remind patients not to get up. \| \| Impaired Gait or Mobility \| Patients with impaired gait or mobility will need assistance with mobility during their hospital stay. All patients should have any needed assistive devices, such as canes or walkers, in good repair at the bedside and within safe reach. If patients bring their assistive devices from home, staff should make sure these devices are safe for use in the hospital environment. Even with assistive devices, patients often need staff assistance when transferring out of bed or walking. \| \| Frequent Toileting Needs \| Patients with frequent toileting needs should be taken to the toilet on a regular basis via a scheduled rounding protocol. See Table 5.6b for a rounding protocol. \| \| Visual Impairment \| Patients with visual impairment should have clean corrective lenses easily within reach and applied when walking. \| \| High-Risk Medications (medicines that could cause sedation, confusion, impaired balance, orthostatic blood pressure changes, or cause frequent urination) \| Patients on high-risk medications should have their medications reviewed by a pharmacist with fall risk in mind and recommendations made to the prescribing provider for discontinuation, substitution, or dose adjustment when possible. If a pharmacist is not immediately available, the prescribing provider should carry out a medication review. See Table 5.6c for a tool to review medications for fall risk. Patients on medications that cause orthostatic hypotension should have their orthostatic blood pressure routinely checked and reported. The patient and their caregivers should be educated about fall risk and steps to prevent falls when the patient is taking these medications. \| \| Frequent Falls \| Patients with a history of frequent falls should have their risk for injury assessed, including checking for a history of osteoporosis and use of aspirin and anticoagulants. \| Scheduled Hourly Rounding Scheduled hourly rounds are scheduled hourly visits to each patient’s room to integrate fall prevention activities with the rest of a patient’s care. Scheduled hourly rounds have been found to greatly decrease the incidence of falls. See below for a list of activities to complete during hourly rounds. These activities can be completed by unlicensed assistive personnel, nurses, or nurse managers.Agency for Healthcare Research and Quality. (2018, July). Preventing falls in hospitals. https://www.ahrq.gov/patient-safety/settings/hospital/fall-prevention/toolkit/index.html Hourly Rounding Protocol.Agency for Healthcare Research and Quality. (2018, July). Preventing falls in hospitals. https://www.ahrq.gov/patient-safety/settings/hospital/fall-prevention/toolkit/index.html - Assess patient pain levels using a pain-assessment scale. (If staff other than a nurse is doing the rounding and the patient is in pain, contact the nurse immediately so the patient does not have to use the call light for pain medication.) - Put pain medication that is ordered “as needed” on an RN’s task list and offer the dose when it is due. - Offer toileting assistance. - Ensure the pCheck that the bed is in the locked position.atient is using correct footwear (e.g., specific shoes/slippers, no-skid socks). - Place the hospital bed in a low position when the patient is resting; ask if the patient needs to be repositioned and is comfortable. - Make sure the call light/call bell button is within the patient’s reach and the patient can demonstrate accurate use. - Put the telephone within the patient’s reach. - Put the TV remote control and bed light switch within the patient’s reach. - Put the bedside table next to the bed or across the bed. - Put the tissue box and water within the patient’s reach. - Put the garbage can next to the bed. - Prior to leaving the room, ask, “Is there anything I can do for you before I leave?” - Tell the patient that a member of the nursing staff (use names on white board) will be back in the room in an hour to round again. Medications Causing Elevated Risk for Falls Evaluate medication-related fall risk for patients on admission and at regular intervals thereafter. Add up the point value (risk level) in Table 5.6b for every medication the patient is taking. If the patient is taking more than one medication in a particular risk category, the score should be calculated by (risk level score) x (number of medications in that risk level category). For a patient at risk, a pharmacist should review the patient’s list of medications and determine if medications may be tapered, discontinued, or changed to a safer alternative.Agency for Healthcare Research and Quality. (2018, July). Preventing falls in hospitals. https://www.ahrq.gov/patient-safety/settings/hospital/fall-prevention/toolkit/index.html Table 5.6b Medications Causing High Risk for FallsAgency for Healthcare Research and Quality. (2018, July). Preventing falls in hospitals. https://www.ahrq.gov/patient-safety/settings/hospital/fall-prevention/toolkit/index.html \| Point Value (Risk Level) \| Medication Class \| Fall Risks \| \|---\|---\|---\| \| 3 (High) \| Antipsychotics, anticonvulsants, and benzodiazepines \| Sedation, dizziness, postural disturbances, altered gait and balance, and impaired cognition \| \| 2 (Medium) \| Antihypertensives, cardiac drugs, antiarrhythmics, and antidepressants \| Induced orthostasis, impaired cerebral perfusion, and poor health status \| \| 1 (Low) \| Diuretics \| Increased ambulation and induced orthostasis \| \| Score ≥ 6 \| Elevated risk for falls; ask pharmacist or prescribing provider to evaluate medications for possible modification to reduce risk \| View tools used to assess delirium and confusion in the Delirium Evaluation Bundle shared by the Agency for Healthcare Research and Quality. 5.7 Restraints Open Resources for Nursing (Open RN) Definition of Restraints Restraints are devices used in health care settings to prevent patients from causing harm to themselves or others when alternative interventions are not effective. A restraint is a device, method, or process that is used for the specific purpose of restricting a patient’s freedom of movement without the permission of the person. See Figure 5.6“PinelRestraint.jpg” by James Heilman, MD is licensed under CC BY-SA 4.0 for an image of a simulated patient with restraints applied. Restraints include mechanical devices such as a tie wrist device, chemical restraints, or seclusion. The Joint Commission defines chemical restraint as a drug used to manage a patient’s behavior, restrict the patient’s freedom of movement, or impair the patient’s ability to appropriately interact with their surroundings that is not standard treatment or dosage for the patient’s condition. It is important to note that the definition states the medication “is not standard treatment or dosage for the patient’s condition.”The Joint Commission. https://www.jointcommission.org/ Seclusion is defined as the confinement of a patient in a locked room from which they cannot exit on their own. It is generally used as a method of discipline, convenience, or coercion. Seclusion limits freedom of movement because, although the patient is not mechanically restrained, they cannot leave the area. Although restraints are used with the intention to keep a patient safe, they impact a patient’s psychological safety and dignity and can cause additional safety issues and death. A restrained person has a natural tendency to struggle and try to remove the restraint and can fall or become fatally entangled in the restraint. Furthermore, immobility that results from the use of restraints can cause pressure injuries, contractures, and muscle loss. Restraints take a large emotional toll on the patient’s self-esteem and may cause humiliation, fear, and anger. Restraint Guidelines The American Nurses Association (ANA) has established evidence-based guidelines that state a restraint-free environment is the standard of care. The ANA encourages the participation of nurses to reduce patient restraints and seclusion in all health care settings. Restraining or secluding patients is viewed as contrary to the goals and ethical traditions of nursing because it violates the fundamental patient rights of autonomy and dignity. However, the ANA also recognizes there are times when there is no viable option other than restraints to keep a patient safe, such as during an acute psychotic episode when patient and staff safety are in jeopardy due to aggression or assault. The ANA also states that restraints may be justified in some patients with severe dementia or delirium when they are at risk for serious injuries such as a hip fracture due to falling. The ANA provides the following guidelines: “When restraint is necessary, documentation should be done by more than one witness. Once restrained, the patient should be treated with humane care that preserves human dignity. In those instances where restraint, seclusion, or therapeutic holding is determined to be clinically appropriate and adequately justified, registered nurses who possess the necessary knowledge and skills to effectively manage the situation must be actively involved in the assessment, implementation, and evaluation of the selected emergency measure, adhering to federal regulations and the standards of The Joint Commission (2009) regarding appropriate use of restraints and seclusion.”American Nurses Association. (2012). Position statement: Reduction of patient restraint and seclusion in health care settings. https://www.nursingworld.org/practice-policy/nursing-excellence/official-position-statements/id/reduction-of-patient-restraint-and-seclusion-in-health-care-settings/ Nursing documentation typically includes information such as patient behavior necessitating the restraint, alternatives to restraints that were attempted, the type of restraint used, the time it was applied, the location of the restraint, and patient education regarding the restraint. Any health care facility that accepts Medicare and Medicaid reimbursement must follow federal guidelines for the use of restraints. These guidelines include the following: - When a restraint is the only viable option, it must be discontinued at the earliest possible time. - Orders for the use of seclusion or restraint can never be written as a standing order or PRN (as needed). - The treating physician must be consulted as soon as possible if the restraint or seclusion is not ordered by the patient’s treating physician. - A physician or licensed independent practitioner must see and evaluate the need for the restraint or seclusion within one hour after the initiation. - The patient must be continually assessed. Generally, the best practice is every 15 minutes for continued use of the restraint, and in the case of an applied restraint, the restraint should be removed and the area assessed every hour. Some agencies require a 1:1 patient sitter when restraints are applied. - Each written order for a physical restraint or seclusion is limited to 4 hours for adults, 2 hours for children and adolescents ages 9 to 17, or 1 hour for patients under 9. The original order may only be renewed in accordance with these limits for up to a total of 24 hours. After the original order expires, a physician or licensed independent practitioner (if allowed under state law) must see and assess the patient before issuing a new order.HealthPartners. (n.d.). Patients’ bill of rights (federal). https://www.healthpartners.com/care/hospitals/regions/patient-guest-support/federal-rights/ Side Rails and Enclosed Beds Side rails and enclosed beds may also be considered a restraint, depending on the purpose of the device. Recall the definition of a restraint as “a device, method, or process that is used for the specific purpose of restricting a patient’s freedom of movement or access to movement without the permission of the person.” If the purpose of raising the side rails is to prevent a patient from voluntarily getting out of bed or attempting to exit the bed, then use of the side rails would be considered a restraint. On the other hand, if the purpose of raising the side rails is to prevent the patient from inadvertently falling out of bed, then it is not considered a restraint. If a patient does not have the physical capacity to get out of bed, regardless if side rails are raised or not, then the use of side rails is not considered a restraint.The Joint Commission. (2020, June 29). Restraint and seclusion – Enclosure beds, side rails, and mitts. https://www.jointcommission.org/standards/standard-faqs/critical-access-hospital/provision-of-care-treatment-and-services-pc/000001668/ Hand Mitts A hand mitt is a large, soft glove that covers a confused patient’s hand to prevent them from inadvertently dislodging medical equipment. Hand mitts are considered a restraint by The Joint Commission if used under these circumstances: - Are pinned or otherwise attached to the bed or bedding - Are applied so tightly that the patient’s hands or finger are immobilized - Are so bulky that the patient’s ability to use their hands is significantly reduced - Cannot be easily removed intentionally by the patient in the same manner it was applied by staff, considering the patient’s physical condition and ability to accomplish the objectiveThe Joint Commission. (2020, June 29). Restraint and seclusion – Enclosure beds, side rails, and mitts. https://www.jointcommission.org/standards/standard-faqs/critical-access-hospital/provision-of-care-treatment-and-services-pc/000001668/ It is important for the nurse to be aware of current best practices and guidelines for restraint use because they are continuously changing. For example, meal trays on chairs were previously used in long-term care facilities to prevent residents from getting out of the chair and falling. However, by the definition of a restraint, this action is now considered a restraint and is no longer used. Instead, several alternative interventions to restraints are now being used. Alternatives to Restraints Many alternatives to using restraints in long-term care centers have been developed. Most interventions focus on the individualization of patient care and elimination of medications with side effects that cause aggression and the need for restraints. Common interventions used as alternatives to restraints include routine daily schedules, regular feeding times, easing the activities of daily living, and reducing pain.Raveesh, B. N., Gowda, G. S., & Gowda, M. (2019). Alternatives to use of restraint: A path toward humanistic care. Indian Journal of Psychiatry, 61(Suppl 4), S693–S697. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6482675/ Diversionary techniques such as television, music, games, or looking out a window can also be used to help to calm a restless patient. Encouraging restless patients to spend time in a supervised area, such as a dining room, lounge, or near the nurses’ station, helps to prevent their desire to get up and move around. If these techniques are not successful, bed and chair alarms or the use of a sitter at the bedside are also considered alternatives to restraints. 5.8 Safety Considerations Across the Life Span Open Resources for Nursing (Open RN) To promote safety for patients of all ages, nurses should be knowledgeable about safety risks according to age and developmental stages because the types and frequencies of accidents vary among age groups. Information from the Centers for Disease Control (CDC) regarding safety tips for each age group is summarized in the following subsections.Centers for Disease Control and Prevention. (2020, October 8). Parent information. https://www.cdc.gov/parents/index.html Infants and Preschoolers Drowning is the leading cause of death in children aged 1-3 years. Motor vehicle accidents, falls, choking, and accidental poisoning are also safety concerns for this age group. Infants and toddlers are curious, but they lack the judgement to recognize the dangers of their actions, so childproofing the home and providing adult supervision are essential for this developmental age group.Centers for Disease Control and Prevention. (2020, October 8). Parent information. https://www.cdc.gov/parents/index.html See Figure 5.7“ARISE Newborn in Car Seat 144049.jpg” by ARISE project is licensed under CC BY 4.0 for an image of an infant car seat used to protect infants in the event of a motor vehicle accident. Nurses help educate parents about the proper use, positioning, and installation of car seats. School-Aged Children In children aged 4-11, motor vehicle injuries are a major cause of unintentional injury, along with drowning and poisoning. This age group is more aware of dangers and limitations, but adult supervision is still important. The nurse should educate parents of school-aged children about safety seats, booster seats, or shoulder seat belts while riding in the car.Centers for Disease Control and Prevention. (2020, October 8). Parent information. https://www.cdc.gov/parents/index.html Bicycle accidents are also a common concern in this age group. Many bike accidents involve the head or face because of the lack of helmet use. Nurses provide health teaching to school-aged children regarding bicycle safety and helmet use. See Figure 5.8“539478754.jpg” by thechatat is used under license from Shutterstock.com for an image of a girl wearing a bike helmet. Because this age group is beginning to enjoy more independence, basic instructions and education on how to recognize and respond to potentially dangerous situations with strangers should also be provided. Parents should also be educated about the AMBER alert system that can be activated if a child is missing and believed to be kidnapped or in danger. This AMBER alert system uses the resources of law enforcement and the media to notify the public about a possible abduction or a missing child in danger.Amber Alert. https://amberalert.ojp.gov/ Nurses must also be aware of signs of maltreatment and child abuse because millions of children are affected each year. Child abuse includes physical, sexual, emotional abuse, and neglect. According to the American Academy of Child and Adolescent Psychiatry (AACAP), after abuse or violence, many children develop mental health problems, including depression and posttraumatic stress disorder. These children may also have serious medical problems, learning problems, and problems getting along with friends and family members. Every state has laws that require health care professionals to report suspected child abuse no matter what form this abuse takes.American Academy of Child & Adolescent Psychiatry. (2020, April). Trauma and child abuse resource center. https://www.aacap.org/AACAP/Families_and_Youth/Resource_Centers/Child_Abuse_Resource_Center/Home.aspx Adolescents Motor vehicle accidents are the number one cause of death for adolescents. Teens aged 16-19 are three times more likely to be in a fatal crash than drivers older than age 20. Adolescent males are twice as likely to die in a motor vehicle accident than females of the same age. Texting while driving is a common cause of distracted driving and accidents in adolescents. Because much of an adolescent’s time is spent away from the home, it is difficult for parents to control many of the decisions that adolescents make. Nurses educate teenagers to use seat belts, obey speed limits, and never use a cell phone or text while driving.Centers for Disease Control and Prevention. (2020, October 8). Parent information. https://www.cdc.gov/parents/index.html See Figure 5.9“texting-while-driving/man-texting-while-driving-md.jpg” by unknown at QuoteInspector.com is licensed under CC BY-ND 4.0. for an image reminding teenage drivers to not text and drive. Traumatic brain injuries (TBI) may occur in this age group due to participation in sports and recreation-related activities. TBI results from a blow, jolt, or hit to the head that causes a disruption in blood function or flow to the brain. Nurses should always be alert for indications of a concussion when a sports injury has occurred. Signs of a concussion requiring immediate medical attention include the following: - Headache, vomiting, balance problems, fatigue, or drowsiness - A dazed and confused appearance or difficulty concentrating or remembering; confusion - Emotional irritability, nervousness, or a change in personality The CDC has comprehensive information and education materials for parents, coaches, players, and health care providers as part of their “Heads Up” program.Centers for Disease Control and Prevention. (2020, November 20). Helmet safety. https://www.cdc.gov/headsup/helmets/index.html Substance abuse is another significant concern in the adolescent population and includes substances such as tobacco, alcohol, illicit drugs, prescription medication, over-the-counter medications, and bath salts. The National Institutes of Health provides many resources for educating teens and their parents about substance abuse.National Institute on Drug Abuse. (n.d.). NIDA for teens. https://teens.drugabuse.gov/ Adults Intimate partner violence and substance abuse are common safety issues in the adult population. Intimate Partner Violence Intimate partner violence (IPV) is widespread in the United States and is the most prevalent adult safety issue. Intimate partner violence includes physical or sexual violence, stalking, and psychological or coercive aggression by current or former intimate partners. Victims can be female or male, and sexual orientation can be heterosexual or LGBTQ+. The nurse is often the initial health care professional in contact with a victim of IPV. Prompt recognition of a potential or actual threat to patient and staff safety is crucial. It is often the nurse’s assessment that plays an important role in identifying a patient experiencing IPV. Compassion and understanding are important to show to this vulnerable population. Effective communication is necessary to help victims come forward and share their experiences of abuse. IPV is a complex issue, and the patient may not initially consider leaving the abuser as an option. See Figure 5.10“Domestic_violence_free-zone.jpg” by Ben Pollard is licensed under CC BY-SA 2.0 for an image of a sign in a community demonstrating support against domestic violence. See the following hyperlinks for tools and resources to share with patients experiencing IPV. For example, the Danger Assessment Tool is a self-administered survey that is free to use and is available in several languages.Danger Assessment. https://www.dangerassessment.org/DATools.aspx Nurses can refer patients experiencing IPV to the National Center on Domestic Violence, the Trauma and Mental Health database for resources,National Center on Domestic Violence, Trauma & Mental Health. (n.d.). National domestic violence organizations. http://www.nationalcenterdvtraumamh.org/resources/national-domestic-violence-organizations/ and the National Domestic Violence Hotline for free, confidential support.National Domestic Violence Hotline. https://www.thehotline.org/ Most importantly, nurses should assist patients experiencing IPV to create a safety plan. View the tools and resources available at these hyperlinks to share with individuals experiencing intimate partner violence: Substance Abuse Substance abuse is defined by the World Health Organization (WHO) as a maladaptive pattern of using alcohol and/or drugs despite it causing persistent social, occupational, psychological, or physical problems that can be physically hazardous. Substance abuse continues to be a safety issue that affects adults across all socioeconomic levels. In America over 450,000 people died between 1999 and 2018 as a result of an opioid overdose.Centers for Disease Control and Prevention. (2020, December 17). Opioid overdose. https://www.cdc.gov/drugoverdose/ The abuse of prescription pain medication (such as oxycontin and fentanyl) and heroin is a national crisis that plagues social and economic welfare. Substance abuse not only affects an individual, but also causes harm to their family members. Early identification of substance abuse, rehabilitation interventions, and continued support are key for helping the individual, as well as their family members, in the recovery process. See Figure 5.11“Heroin syringe” by Thomas Marthinsen is licensed under CC BY-NC-SA 2.0 for an image of a heroin needle found in a community setting. Older Adults According to the Centers for Disease Control and Prevention, falls and motor vehicle accidents are leading causes of injury in older adults. However, several other issues pose significant hazards for this population, such as fires, accidental overdosing on medications (due to poor eyesight and confusion), elder abuse, and financial exploitation.Centers for Disease Control and Pevention (n.d.) Injury Prevention and Control. https://www.cdc.gov/injury/index.html In most reported cases of elder abuse, a caregiver or a person in trusted relationship is the perpetrator. For various reasons such as fear and disappointment, most of these cases go unreported. Abuse, including neglect and exploitation, is experienced by about 1 in 10 people aged 60 and older who live at home. From 2002 to 2016, more than 643,000 older adults were treated in the emergency department for nonfatal assaults and over 19,000 homicides occurred.Centers for Disease Control and Prevention (n.d.) Elder Abuse. https://www.cdc.gov/violenceprevention/elderabuse/ Read an example of an older adult experiencing financial exploitation in the following box. Consider the story of John, a 92-year-old male who lost his wife over a year ago and has been lonely ever since. He lives alone in a large home in the country. John hired a repairman to fix his roof. The repairman befriended John, bringing him homemade cookies and pies and even running errands for him. The repairman often stayed for coffee, and the two of them spent time talking about fishing and gardening. The repairman convinced John to take out a reverse mortgage to pay for additional improvements on his home. Then, knowing John’s bank account numbers and login information, the repairman stole $250,000 that John received for his reverse mortgage. Most victims of elder abuse are frequently seen in the emergency department several times before they are admitted to the hospital. Nurses must be alert to any indications of elder abuse, such as suspicious injuries or behaviors, and report suspected incidents to local adult protective services agencies. Commons signs of elder abuse or maltreatment include the following:Nursing Home Abuse Center. (2020, January 8). Signs of elder abuse. https://www.nursinghomeabusecenter.com/elder-abuse/signs/ - Bruises, cuts, burns, or broken bones that are unexplainable or suspiciously explained - Malnourishment or weight loss - Poor hygiene, an unkempt appearance, unclean clothing, or dirty, matted hair - Foul odor from clothing or body - Anxiety, depression, or confusion - Unexplained transactions or loss of money - Withdrawal from family members or friends View additional resources related to elder abuse using the hyperlinks in the following box. Additional resources for older adults suspected as being victims of elder abuse: 5.9 Environmental Safety Open Resources for Nursing (Open RN) In addition to promoting safety for patients and their families, it is important for nurses to be aware of safety risks in the environments and to take measures to protect themselves. Common safety risks to nurses include sharps injuries, exposure to blood-borne pathogens, lifting injuries, and lack of personal protective equipment (PPE). Workplace Safety The World Health Organization (WHO) defines a healthy environment as a place of physical, mental, and social well-being supporting optimal health and safety. The American Nurses Association (ANA) created the Nurses’ Bill of Rights, a document that sets forth seven basic principles concerning expectations for workplace environments. One of the ANA principles states, “Nurses have the right to a work environment that is safe for themselves and their patients.” American Nurses Association. (n.d.). Healthy work environment. https://www.nursingworld.org/practice-policy/work-environment/ Environmental Health is also one of the ANA Standards of Professional Performance. This standard includes “creating a safe and healthy workplace and professional environment.”American Nurses Association. (2021). Nursing: Scope and standards of practice (4th ed.). American Nurses Association. Preventing Sharps Injuries and Blood-Borne Pathogen Exposure Exposure to sharps and blood-borne pathogens is a critical safety issue that nurses face in the workplace.American Nurses Association. (n.d.). Healthy work environment. https://www.nursingworld.org/practice-policy/work-environment/Blood-borne pathogen exposure can cause life-threatening illnesses such as hepatitis B, hepatitis C, and HIV. Regulations and laws, such as the Blood-borne Pathogen Standard from the Occupational Safety and Health Administration (OSHA) and the Needlestick Safety and Prevention Act of 2002, have been effective in significantly reducing sharps injuries and blood exposures among health care workers. Areas covered by these regulations include sharps disposal practices, evaluation and selection of safety-engineered sharps devices and personal protective equipment (PPE), training, record keeping for needlestick injuries, hepatitis B vaccination, and post exposure follow-up. Medical device manufacturers have also played an important role in reducing sharps injury risks to health care workers by developing innovative safety-engineered technology, such as needleless IV access devices.American Nurse. (2012, September 11). Moving the sharps safety agenda forward: Consensus statement and call to action. https://www.myamericannurse.com/moving-the-sharps-safety-agenda-forward-consensus-statement-and-call-to-action/ While substantial progress has been made to reduce injuries, preventable sharps injuries and blood exposures continue to occur in health care settings. According to the Centers for Disease Control and Prevention (CDC), around 385,000 sharps-related injuries occur annually among health care workers in hospitals, but it has been estimated that as many as half of injuries go unreported.American Nurses Association. (n.d.). Healthy work environment. https://www.nursingworld.org/practice-policy/work-environment/ See Figure 5.12“Sharps Container.jpg” by William Rafti of the William Rafti Institute is licensed under CC BY 2.5 of a sharps container used to prevent sharps-related injuries. If you do experience a sharps injury or are exposed to the blood or other body fluid of a patient, follow agency and school policy and immediately follow these steps: - Wash needlesticks and cuts with soap and water. - Flush splashes to the nose, mouth, or skin with water. - Irrigate eyes with clean water, saline, or sterile irrigants. - Report the incident to your supervisor. - Immediately seek medical treatment.Centers for Disease Control and Prevention. (2016, October 5). Bloodborne infectious diseases: HIV/AIDS, hepatitis B, hepatitis C. National Institute for Occupational Safety and Health. https://www.cdc.gov/niosh/topics/bbp/emergnedl.html Safe Patient Handling Back injuries and other musculoskeletal disorders can be caused by one bad patient lift or from the daily wear and tear of manually lifting patients. At least 56% of nurses have reported pain from musculoskeletal disorders that were exacerbated by requirements of their job. Consequences of these injuries can be devastating to nurses and their careers; musculoskeletal injuries related to patient handling are responsible for more lost work time, long-term medical care needs, and permanent disabilities than any other work-related injury. Even using proper body mechanics and the use of gait belts can result in patient handling injuries in nurses and health care workers. The ANA has established safe patient handling and mobility initiatives with the goal of complete elimination of manual patient handling.American Nurses Association. (2015, September). Safe patient handling & mobility: Understanding the benefits of a comprehensive SPHM program [Brochure]. https://www.nursingworld.org/~498de8/globalassets/practiceandpolicy/work-environment/health–safety/ana-sphmcover__finalapproved.pdf See Figure 5.13“User-Integra-lifter1.jpg” by Integracp is licensed under CC BY-SA 3.0 for an example of safe patient handling equipment. View these videos on safe patient handling and mobility from the ANA: Preventing Nurse Injuries American Nurses Association. (2015, July 7). Preventing nurse injuries. [Video]. YouTube. All rights reserved. https://youtu.be/qJH-91w5PHA ANA Presents Safe Patient Handling and MobilityAmerican Nurses Association. (2016, April 6). ANA presents safe patient handling and mobility. [Video]. YouTube. All rights reserved. https://youtu.be/Bss2VEvrdcw Personal Protective Equipment The Occupational Safety and Health Administration (OSHA) requires employers to provide personal protective equipment (PPE) to their workers and ensure its proper use.United States Department of Labor. (n.d.). Personal protective equipment. Occupational Safety and Health Administration. https://www.osha.gov/personal-protective-equipment In health care settings, the use of PPE includes gloves, gowns, goggles, face shields, and N95 respirators according to a patient’s condition. Health care workers rely on personal protective equipment to protect themselves and their patients from being infected and infecting others. It is vital to follow agency procedures regarding PPE and transmission precautions to avoid exposure to infectious disease. See Figure 5.14“Healthcare_workers_wearing_PPE_03.jpg” by Javed Anees is licensed under CC0 1.0 for an image of health care team members wearing PPE. Unfortunately, the COVID-19 pandemic created global shortages of PPE, resulting in many nurses and health care workers being exposed to the fatal disease. The ANA continues to advocate for adequate PPE for nurses in their work environments. Read more about PPE shortages in the hyperlink below. Explore the Healthy Work Environment web page by the American Nursing Association (ANA) for additional strategies that promote safe work environments for nurses, including the Nurses’ Bill of Rights and ways to put this plan into action. 5.10 Putting It All Together Patient Scenario Mr. Olson is a 64-year-old patient admitted to the medical surgical floor with a diagnosis of pneumonia. The patient has severe macular degeneration and limited visual acuity. He is alert and oriented but notes that he has suffered a “few stumbles” at home over the last few weeks. He ambulates without assistance but relies heavily on tactile cues to help provide guidance. Applying the Nursing Process Assessment: The nurse notes that Mr. Olson’s macular degeneration and limited visual acuity pose a significant safety risk. He has reported “stumbling” at home and uses tactile cues to establish room boundaries. Based on the assessment information that has been gathered, the following nursing care plan is created for Mr. Olson. Nursing Diagnosis: Risk for Injury related to physical barrier associated with alteration in visual acuity. Overall Goal: The patient will be free from injury or falls. SMART Expected Outcome: Mr. Olson will be free from injury throughout his hospitalization. Planning and Implementing Nursing Interventions: The nurse will provide the patient with education regarding the room layout and tactile boundary cues. The nurse will keep the patient’s room free from clutter and provide appropriate lighting. The nurse will instruct the patient to utilize the call light and request assistance when ambulating throughout the room. The nurse will provide the patient with nonskid footwear to enhance safety during ambulation. Sample Documentation Mr. Olson is at risk for injury as a result of his decreased visual acuity and hospitalization in an unfamiliar environment. The patient has been provided education and safety equipment to decrease his risk of injury. The patient has received education regarding the room layout and has been encouraged to request assistance when ambulating about the room. Evaluation: During the patient’s hospitalization, Mr. Olson utilizes the recommended safety equipment and requests assistance when ambulating and no falls occurred. SMART outcome was “met.” 5.11 Learning Activities Open Resources for Nursing (Open RN) Learning Activities (Answers to “Learning Activities” can be found in the “Answer Key” at the end of the book. Answers to interactive activity elements will be provided within the element as immediate feedback.) Assessing a patient’s risk for falls and planning interventions to prevent falls are common safety strategies completed by nurses. This section uses a patient scenario to demonstrate how to use the nursing process to assess a patient and then create a nursing care plan to prevent falls. Begin by reading the Handoff Report received from the nurse on the previous shift. Handoff Report Mr. Moore is a 72-year-old widower recovering in the hospital after sustaining injuries he received from a fall he sustained at home. See Figure 5.15 for an image of Mr. Moore.“old-man-1208210_960_720.jpg” by Free-Photos at Pixabay is licensed under CC0 He fractured his right hip and underwent surgical repair two days ago. He is receiving IV fluids and morphine for pain control. He has a history of hypertension and cardiovascular disease. He wears glasses and hearing aids. Per recommendations from the physical therapist, he is able to transfer with one assist with a walker, but is weak on his right side. He has an order to ambulate at least 100 feet four times daily with a wheeled walker. He is 6 feet tall and weighs 165 pounds. Prior to the fall, he lived at home alone independently, and he is looking forward to returning home. Assessment The nurse collects the following assessment findings: - Vital Signs: Blood pressure 90/60, heart rate 56, respiratory rate 18, temperature 37 degrees Celsius, pulse oximetry reading 92%, current pain level 0 - Alert and oriented x 3 to person, place, and time - Lungs clear - Cardiovascular Assessment: Heart rate is regular, capillary refill less than 3 seconds in fingers and toes, pedal pulses 2+ - Right lower extremity strength is 1+ (weak) - Ambulates with walker with assistance; gait is unsteady Critical Thinking Questions 1. Describe the fall risk factors for Mr. Moore. 2. Use the Morse Fall Risk Assessment tool to assess Mr. Moore’s risk for falling. Diagnosis The NANDA-I nursing diagnosis is established: Risk for Falls as evidenced by lower extremity weakness and difficulty with gait. Outcome Identification Overall Goal: Mr. Moore will remain free from falls during his hospitalization stay. SMART Expected Outcomes: - Mr. Moore will not experience a fall during hospitalization. - Mr. Moore will correctly use his assistive device (walker) every time he ambulates during hospitalization. Planning Interventions The following interventions are planned based on Mr. Moore’s fall risk factors. - Remove clutter from the floor. - Provide adequate lighting with a night-light at the bedside. - Use half side rails to prevent falls from the bed. - Monitor gait, balance, and fatigue with ambulation and encourage resting as needed. - Place personal items within easy reach of the patient at the bedside. - Provide an elevated toilet seat. - Encourage the use of prescribed glasses and hearing aids when walking. - Obtain orthostatic blood pressures daily and notify the provider as indicated. - Ensure the patient wears shoes that fit properly, are fastened securely, and have no-skid soles. - Suggest home adaptations to improve safety after discharge, such as adjusting the toilet seat height, installing grab bars in the bathroom, and using a rubber mat in the shower. Critical Thinking Question 3. What additional interventions could be implemented for Mr. Moore to reduce his risk of falls that target his specific risk factors? Implementation of Interventions The following day, upon entering the room, you find Mr. Moore has climbed out of bed and is on his way to the bathroom. He states, “I need to go to the bathroom for a bowel movement and didn’t have time to ring the call light and wait.” You assist him with his walker, but he seems unsteady on his feet as he walks toward the bathroom. You’re not sure if he will make it to the toilet without falling. He says, “We need to hurry or I’m not going to make it.” Critical Thinking Question: 4. What is the best response? Evaluation The nurse evaluates Mr. Moore’s progress based on the established expected outcomes: - Mr. Moore will not experience a fall during hospitalization: Outcome Met. - Mr. Moore will use his assistive device (walker) correctly during hospitalization: Outcome Partially Met. Mr. Moore forgets to call for assistance and uses a walker when he needs to go to the bathroom. A “stop” sign has been placed within patient view to remind him to use the call light before getting up. In addition to hourly rounding, toileting will be performed at scheduled intervals every two hours. An icon has been posted on the doorframe to alert staff that the patient is at high risk for falls. In addition to the bed being kept low and locked, a mat will be placed next to the bed at night. If Mr. Moore continues to forget to call for assistance, a bed alarm will be placed to alert staff of movement so that quick assistance can be offered. An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=955#h5p-62 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=955#h5p-15 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=955#h5p-16 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=955#h5p-96 Functional Ability Case Study by Susan Jepsen for Lansing Community College are licensed under CC BY 4.0 V Glossary Open Resources for Nursing (Open RN) At-risk behavior: According to the Just Culture model, an error that occurs when a behavioral choice is made that increases risk where risk is not recognized or is mistakenly believed to be justified. Chemical restraint: A drug used to manage a patient’s behavior, restrict the patient’s freedom of movement, or impair the patient’s ability to appropriately interact with their surroundings that is not a standard treatment or dosage for the patient’s condition. Culture of safety: The behaviors, beliefs, and values within and across all levels of an organization as they relate to safety and clinical excellence, with a focus on people. Handoff reports: A transfer and acceptance of patient care responsibility achieved through effective communication. It is a real-time process of passing patient specific information from one caregiver to another, or from one team of caregivers to another, for the purpose of ensuring the continuity and safety of the patient’s care. Healthy environment: A place of physical, mental, and social well-being supporting optimal health and safety. Human factors: A science that focuses on the interrelationships between humans, the tools and equipment they use in the workplace, and the environment in which they work. Intimate Partner Violence (IPV): Physical or sexual violence, stalking, and psychological or coercive aggression by current or former intimate partners. ISBARR: A mnemonic for the components of health care team member communication that stands for Introduction, Situation, Background, Assessment, Request/Recommendations, and Repeat back. Just Culture: A quality of an institutional culture of safety where people feel safe raising questions and concerns and reporting safety events in an environment that emphasizes a nonpunitive response to errors and near misses, but clear lines are drawn between human error, at-risk, and reckless behaviors. Learning Culture: A quality of an institutional culture of safety where people regularly collect information and learn from errors and successes. Data is openly shared and evidence-based practices are used to improve work processes and patient outcomes. National Patient Safety Goals: Annual patient safety goals and recommendations tailored for seven different types of health care agencies based on patient safety data from experts and stakeholders. Near misses: An unplanned event that did not result in a patient injury or illness but had the potential to. Never events: Adverse events that are clearly identifiable, measurable, serious (resulting in death or significant disability), and preventable. Reckless behavior: According to the Just Culture model, an error that occurs when an action is taken with conscious disregard for a substantial and unjustifiable risk. Reporting Culture: A quality of an institutional culture of safety where people realize errors are inevitable and are encouraged to speak up for patient safety by reporting errors and near misses. Restraint: A device, method, or process that is used for the specific purpose of restricting a patient’s freedom of movement without the permission of the person. Root cause analysis: A structured method used to analyze serious adverse events to identify underlying problems that increase the likelihood of errors, while avoiding the trap of focusing on mistakes by individuals. Scheduled hourly rounds: Scheduled hourly visits to each patient’s room to integrate fall prevention activities with the rest of a patient’s care. Seclusion: The confinement of a patient in a locked room from which they cannot exit on their own. It is generally used as a method of discipline, convenience, or coercion. Sentinel event: An unexpected occurrence involving death or serious physiological or psychological injury or the risk thereof. Simple human error: According to the Just Culture model, this is an error that occurs when an individual inadvertently does something other than what should have been done. Most errors are the result of human error due to poor processes, programs, education, environmental issues, or situations. These are managed by correcting the cause, looking at the process, and fixing the deviation. Substance abuse: A maladaptive pattern of continued use of alcohol or a drug despite it causing persistent social, occupational, psychological, or physical problems that can be physically hazardous. Universal fall precautions: A set of interventions to reduce the risk of falls for all patients and focus on keeping the environment safe and comfortable. Cognitive Impairments VI 6.1 Cognitive Impairments Introduction Open Resources for Nursing (Open RN) Learning Objectives - Identify factors related to cognitive impairments across the life span - Demonstrate respect for the dignity of the patient with a cognitive impairment - Collect data to identify patients experiencing alterations in cognition - Include adaptations to the environment to maintain safety for the patient with impaired cognition - Incorporate nursing strategies to maximize cognitive functioning - Outline nursing interventions for specific cognitive disorders - Outline resources for patients with a cognitive impairment and their family members or caregivers - Identify evidence-based practices in the care of cognitively impaired patients Cognition is the term used to describe our ability to think. As humans, we are continually receiving input from the world around us and making decisions about how to respond. Some of these decisions are made with awareness, while others are reflexive responses. Infants develop cognitively based on their experiences with their environment. Cognitive processes continue to develop throughout childhood, adolescence, and adulthood as we learn how to adapt and use knowledge to solve problems and reach desired outcomes. Many factors can influence an individual’s continuously-evolving cognitive function from fetal development through adulthood. For example, diseases and health conditions can impair a person’s cognitive development and functioning during childhood and beyond. Impaired ability to think and make decisions can be temporarily affected by things such as infection, alcohol, drugs and medications, poor oxygenation, stress, or grief. Sensory deficits and sensory overload can also affect the ability to process information. (See the “Sensory Impairments” chapter for more information on this topic.) Nurses monitor for changes in mental status and report them to health care providers to assist in the diagnosis and treatment for underlying causes of impairment. This chapter will review cognitive development, as well as common acute and chronic cognitive impairments in adults. 6.2 Basic Concepts Open Resources for Nursing (Open RN) Before learning about cognitive impairment, it is important to understand the physiological processes of normal growth and development. Growth includes physical changes that occur during the development of an individual beginning at the time of conception. Development encompasses these biological changes, as well as social and cognitive changes that occur continuously throughout our lives. Cognition starts at birth and continues throughout the life span. See Figure 6.1“shutterstock_149010437.jpg” by Robert Adrian Hillman is used under license from Shutterstock.com for an image of the human life cycle. There are multiple factors that affect human cognitive development. While there are expected milestones along the way, cognitive development encompasses several different skills that develop at different rates. Cognition takes the form of many paths leading to unique developmental ends. Each human has their own individual experience that influences development of intelligence and reasoning as they interact with one another. With these unique experiences, everyone has a memory of feelings and events that is exclusive to them.Vallotton, C. D., & Fischer, K. W. (2008). Cognitive development. Encyclopedia of infant and early childhood development. Academic Press. https://doi.org/10.1016/B978-012370877-9.00038-4 Developmental Stages As newborns, we learn behavior and communication to help us to interact with the world around us and to fulfill our needs. For example, crying provides communication to cue parents or caregivers about a newborn’s needs. The human brain undergoes tremendous development throughout the first year of life. As infants receive and experience input from the environment, they begin to interact with the individuals around them as they learn and grow. Jean Piaget, a well-known cognitive development theorist, noted that children explore the world as they attempt to make sense of their experiences. His theory explains that humans move from one stage to another as they seek cognitive equilibrium and mental balance. There are four stages in Piaget’s theory of development that occur in children from all cultures: - The first stage is the Sensorimotor period. It extends from birth to approximately two years and is a period of rapid cognitive growth. During this period, infants develop an understanding of the world by coordinating sensory experiences (seeing, hearing) with motor actions (reaching, touching). The main development during the sensorimotor stage is the understanding that objects exist and events occur in the world independently of one’s own actions.McLeod, S. (2020, December 7). Piaget’s theory and stages of development. SimplyPsychology. https://www.simplypsychology.org/piaget.html Infants develop an understanding of what they want and what they must do to have their needs met. They begin to understand language used by those around them to make needs met. - Infants progress from the Sensorimotor period to a Pre-Operational period in their toddler years. This continues through early school age years. This is the time frame when children learn to think in images and symbols. Play is an important part of cognitive development during this period. - Older school age children (age 7 years to 11 years) enter a Concrete Operations period. They learn to think in terms of processes and can understand that there is more than one perspective when discussing a concept.Ginsburg, H. P., & Opper, S. (1988). Piaget’s theory of intellectual development (3rd ed.). Prentice-Hall, Inc. This stage is considered a major turning point in the child’s cognitive development because it marks the beginning of logical or operational thought. - Adolescents transition to the Formal Operations stage around age 12 as they become self-conscious and egocentric. As adolescents enter this stage, they gain the ability to think in an abstract manner by manipulating ideas in their head. Moving toward adulthood, this further develops into the ability to critically reason.Ginsburg, H. P., & Opper, S. (1988). Piaget’s theory of intellectual development (3rd ed.). Prentice-Hall, Inc.,McLeod, S. (2020, December 7). Piaget’s theory and stages of development. SimplyPsychology. https://www.simplypsychology.org/piaget.html Cognitive impairments in children range from mild impairment in these specific operations to profound intellectual impairments leading to minimal independent functioning. The following areas are domains of cognitive functioning: - Attention - Decision-making - General knowledge - Judgment - Language - Memory - Perception - Planning - Reasoning - VisuospatialSchofield, D. W. (2018, December 26). Cognitive deficits. Medscape. https://emedicine.medscape.com/article/917629-overview Intellectual disability (formerly referred to as mental retardation) is a diagnostic term that describes intellectual and adaptive functioning deficits identified during the developmental period. In the United States, the developmental period refers to the span of time prior to the age 18. Children with intellectual disabilities may demonstrate a delay in developmental milestones (e.g., sitting, speaking, walking) or demonstrate mild cognitive impairments that may not be identified until school age. Intellectual disability is typically nonprogressive and lifelong. It is diagnosed by multidisciplinary clinical assessments and standardized testing and is treated with a multidisciplinary treatment plan that maximizes quality of life.Schofield, D. W. (2018, December 26). Cognitive deficits. Medscape. https://emedicine.medscape.com/article/917629-overview See Figure 6.2“22605761265_9f8e65a7ad_k.jpg” by Special Olympics 2017 is in the Public Domain for an image of an adolescent with an intellectual disability participating in a Special Olympics event. Adults and Older Adults There are several physical changes that occur in the brain due to aging. The structure of neurons change, including a decreased number and length of dendrites, loss of dendritic spines, a decrease in the number of axons, an increase in axons with segmental demyelination, and a significant loss of synapses. Loss of synapse is a key marker of aging in the nervous system. These physical changes occur in older adults experiencing cognitive impairments, as well as in those who do not.Murman, D. L. (2015). The impact of age on cognition. Seminars in Hearing, 36(3), 111–121. https://doi.org/10.1055/s-0035-1555115 See Figure 6.3“3546874802_8b4cf9c822_o.jpg” by United Nations Photo is licensed under CC BY-NC-ND 2.0 of an older adult experiencing typical physical changes of aging. It is a common myth that all individuals experience cognitive impairments as they age. Many people are afraid of growing older because they fear becoming forgetful, confused, and incapable of managing their daily life leading to incorrect perceptions and ageism. Ageism refers to stereotyping older individuals because of their age. Losing language skills, becoming unable to make decisions appropriately, and being disoriented to self or surroundings are not normal aging changes. Dementia, Delirium, and Depression If changes in cognition in adults do occur, a complete assessment is required to determine the underlying cause of the change and if it is caused by an acute or chronic condition. For example, dementia is a chronic condition that affects cognition whereas depression and delirium can cause acute confusion with a similar clinical appearance to dementia. Dementia Dementia is a chronic condition of impaired cognition, caused by brain disease or injury, and marked by personality changes, memory deficits, and impaired reasoning. Dementia can be caused by a group of conditions, such as Alzheimer’s disease, vascular dementia, frontal-temporal dementia, and Lewy body disease. Clinical manifestations of dementia include forgetfulness, impaired social skills, and impaired decision-making and thinking abilities that interfere with daily living. It is gradual, progressive, and irreversible.Alzheimer’s Association. (2021). https://www.alz.org/ While dementia is not reversible, appropriate assessment and nursing care improve the safety and quality of life for those affected by dementia. As dementia progresses and cognition continues to deteriorate, nursing care must be individualized to meet the needs of the patient and family. Providing patient safety and maintaining quality of life while meeting physical and psychosocial needs are important aspects of nursing care. Unsafe behaviors put individuals with dementia at increased risk for injury. These unsafe or inappropriate behaviors often occur due to the patient having a need or emotion without the ability to express it, such as pain, hunger, anxiety, or the need to use the bathroom. The patient’s family/caregivers require education and support to recognize that behaviors are often a symptom of dementia and/or a communication of a need and to help them to best meet the needs of their family member.Downing, L. J., Caprio, T. V., & Lyness, J. M. (2013). Geriatric psychiatry review: Differential diagnosis and treatment of the 3 D’s – delirium, dementia, and depression. Current Psychiatry Reports, 15(6), 365. https://doi.org/10.1007/s11920-013-0365-4 Delirium Delirium is an acute state of cognitive impairment that typically occurs suddenly due to a physiological cause, such as infection, hypoxia, electrolyte imbalances, drug effects, or other acute brain injury. Sensory overload, excess stress, and sleep deprivation can also cause delirium. Hospitalized older adults are at increased risk for developing delirium, especially if they have been previously diagnosed with dementia. One third of patients aged 70 years or older exhibit delirium during their hospitalization. Delirium is the most common surgical complication for older adults, occurring in 15 to 25% of patients after major elective surgery and up to 50% of patients experiencing hip-fracture repair or cardiac surgery.Marcantonio, E. R. (2017). Delirium in hospitalized older adults. The New England Journal of Medicine, 377(15), 1456–1466. https://doi.org/10.1056/NEJMcp1605501 The symptoms of delirium usually start suddenly, over a few hours or a few days, and they often come and go. Common symptoms include the following: - Changes in alertness (usually most alert in the morning and decreased at night) - Changing levels of consciousness - Confusion - Disorganized thinking or talking in a way that do not make sense - Disrupted sleep patterns or sleepiness - Emotional changes: anger, agitation, depression, irritability, overexcitement - Hallucinations and delusions - Incontinence - Memory problems, especially with short-term memory - Trouble concentratingMedlinePlus [Internet]. Bethesda (MD): National Library of Medicine (US); [updated 2020, Feb 12]. Delirium; [reviewed 2016, May 13; cited 2021, Feb 17]. https://medlineplus.gov/delirium.html Delirium and dementia have similar symptoms, so it can be hard to tell them apart. They can also occur together. Nurses must closely monitor the cognitive function of all patients and promptly report any changes in mental status to the health care provider. The provider will take a medical history, perform a physical and neurological examination, perform mental status testing, and may order diagnostic tests based on the patient’s medical history. After the cause of delirium is determined, treatment is targeted to the cause to reverse the effects. See Figure 6.4“old-peoples-home-524234_960_720.jpg” by mikegi is licensed under CC0 for an illustration of an older adult experiencing delirium. General interventions to prevent and treat delirium in older adults are as follows: - Control the environment. Make sure that the room is quiet and well-lit, have clocks or calendars in view, and encourage family members to visit. - Ensure a safe environment with the call light within reach and side rails up as indicated. - Administer prescribed medications, including those that control aggression or agitation, and pain relievers if there is pain. - Ensure the patient has their glasses, hearing aids, or other assistive devices for communication in place. Lack of assistive sensory devices can worsen delirium. - Avoid sedatives. Sedatives can worsen delirium. - Assign the same staff for patient care when possible.MedlinePlus [Internet]. Bethesda (MD): National Library of Medicine (US); [updated 2020, Feb 12]. Delirium; [reviewed 2016, May 13; cited 2021, Feb 17]. https://medlineplus.gov/delirium.html Depression Depression is a brain disorder with a variety of causes, including genetic, biological, environmental, and psychological factors. It is a commonly untreated condition in older adults that can result in impaired cognition and difficulty in making decisions. It is likely to occur in response to major life events involving health and loved ones. Having other chronic health problems, such as diabetes, dementia, Parkinson’s disease, cancer, heart disease, and kidney disease, increases the likelihood for depression in older adults and can cause the loss of their ability to maintain independence.Ouldred, E., & Bryant, C. (2008). Dementia care. Part 1: Guidance and the assessment process. British Journal of Nursing, 17(3): 138-145. https://doi.org/10.12968/bjon.2<IP_ADDRESS>401 See Figure 6.5“man-416470_960_720.jpg” by geralt is licensed under CC0 for an illustration of an older adult experiencing symptoms of depression. Symptoms of depression include the following: - Feeling sad or “empty” - Loss of interest in favorite activities - Overeating or not wanting to eat at all - Not being able to sleep or sleeping too much - Feeling very tired - Feeling hopeless, irritable, anxious, or guilty - Aches, pains, headaches, cramps, or digestive problems - Thoughts of death or suicideMedlinePlus [Internet]. Bethesda (MD): National Library of Medicine (US); [updated 2021, Feb 6]. Depression; [reviewed 2016, Nov 4; cited 2021, Feb 17]. https://medlineplus.gov/depression.html Depression is treatable with medication and psychotherapy. However, older adults have an increased risk for suicide, with the suicide rates for individuals over age 85 years the second highest rate overall. Nurses should provide appropriate screening to detect potential signs of depression as an important part of promoting health for older adults. Comparison of Three Conditions When an older adult presents with confusion, determining if it is caused by delirium, dementia, depression, or a combination of these conditions can pose many challenges to the health care team. It is helpful to know the patient’s baseline mental status from a family member, caregiver, or previous health care records. If a patient’s baseline mental status is not known, it is an important patient safety consideration to assume that confusion is caused by delirium with a thorough assessment for underlying causes.Marcantonio, E. R. (2017). Delirium in hospitalized older adults. The New England Journal of Medicine, 377(15), 1456–1466. https://doi.org/10.1056/NEJMcp1605501 See Table 6.2 for a comparison of symptoms of dementia, delirium, and depression.Ouldred, E., & Bryant, C. (2008). Dementia care. Part 1: Guidance and the assessment process. British Journal of Nursing, 17(3): 138-145. https://doi.org/10.12968/bjon.2<IP_ADDRESS>401 Table 6.2 Comparison of Dementia, Delirium, and DepressionOuldred, E., & Bryant, C. (2008). Dementia care. Part 1: Guidance and the assessment process. British Journal of Nursing, 17(3): 138-145. https://doi.org/10.12968/bjon.2<IP_ADDRESS>401 \| Dementia \| Delirium \| Depression \| \| \|---\|---\|---\|---\| \| Onset \| Vague, insidious onset; symptoms progress slowly \| Sudden onset over hours and days with fluctuations \| Onset often rapid with identifiable trigger or life event such as bereavement \| \| Symptoms \| Symptoms may go unnoticed for years. May attempt to hide cognitive problems or may be unaware of them. Often disoriented to time, place, and person. Impaired short-term memory and information processing. Confusion is often worse in the evening (referred to as “sundowning”) \| Often disoriented to time, place, and person. Impaired short-term memory loss and information processing. Confusion is often worse in the evening \| Obvious at early stages and often worse in the morning. Can include subjective complaints of memory loss \| \| Consciousness \| Normal \| Impaired attention/alertness \| Normal \| \| Mental State \| Possibly labile mood. Consistently decreased cognitive performance \| Emotional lability with anxiety, fear, depression, aggression. Variable cognitive performance \| Distressed/unhappy. Variable cognitive performance \| \| Delusions/Hallucinations \| Common \| Common \| Rare \| \| Psychomotor Disturbance \| Psychomotor disturbance in later stages \| Psychomotor disturbance present – hyperactive, purposeless, or apathetic \| Slowed psychomotor status in severe depression \| 6.3 Alzheimer’s Disease Open Resources for Nursing (Open RN) Alzheimer’s disease is an irreversible, progressive brain disorder that slowly destroys memory and thinking skills and eventually the ability to carry out the simplest tasks. It is the most common cause of dementia. In most people with Alzheimer’s disease, symptoms first appear in their mid-60s. One in ten Americans age 65 and older has Alzheimer’s disease.Alzheimer’s Association. (2021). https://www.alz.org/ Scientists continue to unravel the complex brain changes involved in the onset and progression of Alzheimer’s disease. It is thought that changes in the brain may begin a decade or more before memory and other cognitive problems appear. Abnormal deposits of proteins form amyloid plaques and tau tangles throughout the brain. Previously healthy neurons stop functioning, lose connections with other neurons, and die. The damage initially appears to take place in the hippocampus and cortex, the parts of the brain essential in forming memories. As more neurons die, additional parts of the brain are affected and begin to shrink. By the final stage of Alzheimer’s, damage is widespread, and brain tissue has shrunk significantly.National Institute on Aging. (2019, May 22). Alzheimer’s disease fact sheet. U.S. Department of Health & Human Services. https://www.nia.nih.gov/health/alzheimers-disease-fact-sheet See Figure 6.6“Alzheimers_Disease.jpg” by BruceBlaus is licensed under CC BY-SA 4.0 and “24239522109_6b061a9d69_o.jpg” by NIH Image Gallery is licensed under CC0 for an image of the changes occurring in the brain during Alzheimer’s disease. View a video of the changes that occur in the brain during Alzheimer’s disease:National Institute on Aging. (2017, August 23). How Alzheimer’s changes the brain. [Video]. YouTube. All rights reserved. https://youtu.be/0GXv3mHs9AU Symptoms of Early Alzheimer’s Disease There are ten symptoms of early Alzheimer’s disease: - Forgetting recently learned information that disrupts daily life. This includes forgetting important dates or events, asking the same questions over and over, and increasingly needing to rely on memory aids (e.g., reminder notes or electronic devices) or family members for things they used to handle on their own. This is different than a typical age-related change of sometimes forgetting names or appointments, but remembering them later. - Challenges in planning or solving problems. This includes changes in an individual’s ability to develop and follow a plan or work with numbers. For example, they may have trouble following a familiar recipe or keeping track of monthly bills. They may have difficulty concentrating and take much longer to do things than they did before. This is different from a typical age-related change of making occasional errors when managing finances or household bills. - Difficulty completing familiar tasks. This includes trouble driving to a familiar location, organizing a grocery list, or remembering the rules of a favorite game. This symptom is different from a typical age-related change of occasionally needing help to use microwave settings or to record a TV show. - Confusion with time or place. This includes losing track of dates, seasons, and the passage of time. Individuals may have trouble understanding something if it is not happening immediately. Sometimes they may forget where they are or how they got there. This symptom is different from a typical age-related change of forgetting the date or day of the week but figuring it out later. - Trouble understanding visual images and spatial relationships. Vision problems that include difficulty judging distance, determining color or contrast, or causing issues with balance or driving can be symptoms of Alzeheimer’s. This is different from a typical age-related change of blurred vision related to presbyopia or cataracts. (See the “Sensory Impairments” chapter for more information on common vision problems.) - New problems with words in speaking or writing. Individuals with Alzheimer’s may have trouble following or joining a conversation. They may stop in the middle of a conversation and have no idea how to continue or they may repeat themselves. They may struggle with vocabulary, have trouble naming a familiar object, or use the wrong name (e.g., calling a “watch” a “hand-clock”). This is different from a typical age-related change of having trouble finding the right word. - Misplacing things and losing the ability to retrace steps. A person with Alzheimer’s disease may put things in unusual places. They may lose things and be unable to go back over their steps to find them again. They may accuse others of stealing, especially as the disease progresses. This is different from a typical age-related change of misplacing things from time to time and retracing steps to find them. - Decreased or poor judgment. Individuals with Alzheimer’s may experience changes in judgment or decision-making. For example, they may use poor judgment when dealing with money or pay less attention to grooming or keeping themselves clean. This is different from a typical age-related change of making a bad decision or mistake once in a while, like neglecting to change the oil in the car. - Withdrawal from work or social activities. A person living with Alzheimer’s disease may experience changes in the ability to hold or follow a conversation. As a result, he or she may withdraw from hobbies, social activities, or other engagements. They may have trouble keeping up with a favorite team or activity. This is different from a typical age-related change of sometimes feeling uninterested in family or social obligations. - Changes in mood and personality. Individuals living with Alzheimer’s may experience mood and personality changes. They can become confused, suspicious, depressed, fearful, or anxious. They may be easily upset at home, with friends, or when out of their comfort zone. This is different from a typical age-related change of developing very specific ways of doing things and becoming irritable when a routine is disrupted.Alzheimer’s Association. (2021). https://www.alz.org/ Three Stages of Dementia There are three stages of dementia: early, moderate, and advanced. Early stages of dementia include the ten symptoms previously discussed. Patients with moderate dementia require additional assistance with reminders to eat, wash, and use the restroom. They may not recognize family and friends. Behavioral symptoms such as wandering, getting lost, hallucinations, delusions, and repetitive behavior may occur. Patients living at home may engage in risky behavior, such as leaving the house in clothing inappropriate for weather conditions or leaving on the stove burners. Patients with advanced dementia require full assistance in washing, dressing, eating, and toileting. They often have urinary and bowel incontinence. Their gait becomes shuffled or unsteady. There may be increased aggressive behavior, disinhibition, or inappropriate laughing. Eventually they have difficulty eating, swallowing, and speaking, and seizures may develop.Ouldred, E., & Bryant, C. (2008). Dementia care. Part 1: Guidance and the assessment process. British Journal of Nursing, 17(3), 138-145. https://doi.org/10.12968/bjon.2<IP_ADDRESS>401 See Figure 6.7“civilian-service-63616_960_720.jpg” by geralt is licensed under CC0 of a patient with dementia requiring assistance with dressing. There is no single diagnostic test that can determine if a person has Alzheimer’s disease. Health care providers use a patient’s medical history, mental status tests, physical and neurological exams, and diagnostic tests to diagnose Alzheimer’s disease and other types of dementia. During the neurological exam, reflexes, coordination, muscle tone and strength, eye movement, speech, and sensation are tested. Mental status testing evaluates memory, thinking, and simple problem-solving abilities. Some tests are brief, whereas others can be more time-intensive and complex. These tests give an overall sense of whether a person is aware of their symptoms; knows the date, time, and place where they are; can remember a short list of words; and if they can follow instructions and do simple calculations. The Mini Mental Status Examination (MMSE) and Mini-Cog test are two commonly used assessments. During the MMSE, a health professional asks a patient a series of questions designed to test a range of everyday mental skills. The maximum MMSE score is 30 points. A score of 20 to 24 suggests mild dementia, 13 to 20 suggests moderate dementia, and less than 12 indicates severe dementia. On average, the MMSE score of a person with Alzheimer’s declines about two to four points each year. During the Mini-Cog, a person is asked to complete two tasks: remember and then later repeat the names of three common objects and draw a face of a clock showing all 12 numbers in the right places with the time indicated as specified by the examiner. The results of this brief test determine if further evaluation is needed. In addition to assessing mental status, the health care provider evaluates a person’s sense of well-being to detect depression or other mood disorders that can cause memory problems, loss of interest in life, and other symptoms that can overlap with dementia. Diagnostic testing for Alzheimer’s disease may include structural imaging with magnetic resonance imaging (MRI) or computed tomography (CT). These tests are primarily used to rule out other conditions that can cause symptoms similar to Alzheimer’s but require different treatment. For example, structural imaging can reveal brain tumors, evidence of strokes, damage from head trauma, or a buildup of fluid in the brain.Alzheimer’s Association. (2021). https://www.alz.org/ Treatments While there is no cure for Alzheimer’s disease, there are medications to help lessen symptoms of memory loss and confusion and interventions to manage common symptomatic behaviors. Medications The U.S. Food and Drug Administration (FDA) has approved two types of medications, cholinesterase inhibitors and memantine, to treat the cognitive symptoms of Alzheimer’s disease (memory loss, confusion, and problems with thinking and reasoning). While current medications cannot stop the damage Alzheimer’s causes to brain cells, they may help lessen or stabilize symptoms for a limited time by affecting certain chemicals involved in carrying messages among the brain’s nerve cells. Sometimes both types of medications are prescribed together. Cholinesterase inhibitors are prescribed to treat early to moderate symptoms of Alzheimer’s disease related to memory, thinking, language, judgment, and other thought processes. Cholinesterase inhibitors prevent the breakdown of acetylcholine, a neurotransmitter that is vital for learning and memory. It supports communication among nerve cells by keeping acetylcholine high and delays or slows the worsening of symptoms. Effectiveness varies from person to person, and the medications are generally well-tolerated. If side effects occur, they commonly include nausea, vomiting, loss of appetite, and increased frequency of bowel movements. These three cholinesterase inhibitors are commonly prescribed: - Donepezil (Aricept), approved to treat all stages of Alzheimer’s disease - Galantamine (Razadyne), approved for mild-to-moderate stages - Rivastigmine (Exelon), approved for mild-to-moderate stages Memantine (Namenda) and a combination of memantine and donepezil (Namzaric) are approved by the FDA for treatment of moderate to severe Alzheimer’s. Memantine is prescribed to improve memory, attention, reasoning, language, and the ability to perform simple tasks. Memantine regulates the activity of glutamate, a chemical involved in information processing, storage, and retrieval. It improves mental function and the ability to perform daily activities for some people, but it can cause side effects, including headache, constipation, confusion, and dizziness. Other medications may be prescribed to treat specific symptoms of depression, anxiety, or psychosis. However, the decision to use an antipsychotic drug must be considered with extreme caution. Research has shown that these drugs are associated with an increased risk of stroke and death in older adults with dementia. The FDA has ordered manufacturers to label such drugs with a “Black Box” warning about their risks and a reminder that they are not approved to treat dementia symptoms. Individuals with dementia should use antipsychotic medications only under one of the following conditions: - Behavioral symptoms are due to mania or psychosis. - The symptoms present a danger to the person or others. - The person is experiencing inconsolable or persistent distress, a significant decline in function, or substantial difficulty receiving needed care. Antipsychotic medications should not be used to sedate or restrain persons with dementia. The minimum dosage should be used for the minimum amount of time possible, and nurses should carefully monitor for adverse side effects and report them to the health care provider.Alzheimer’s Association. (2021). https://www.alz.org/ Interventions for Symptomatic Behavior Many people find the behavioral changes caused by Alzheimer’s disease to be the most challenging and distressing effect of the disease. The chief cause of behavioral symptoms is the progressive deterioration of brain cells. However, medication, environmental influences, and some medical conditions can also cause symptoms or make them worse. In the early stages of Alzheimer’s disease, people may experience behavior and personality changes, such as irritability, anxiety, and depression. In later stages, other symptoms may occur, including the following: - Aggression and anger - Anxiety and agitation - General emotional distress - Physical or verbal outbursts - Restlessness, pacing, or shredding paper or tissues - Hallucinations (seeing, hearing, or feeling things that are not really there) - Delusions (firmly held beliefs in things that are not true) - Sleep issues and sundowning Sundowning is restlessness, agitation, irritability, or confusion that typically begins or worsens as daylight begins to fade and can continue into the night, making it hard for patients with Alzheimer’s to sleep. Being too tired can increase late-afternoon and early-evening restlessness. Tips to manage sundowning are as follows:National Institute on Aging. (n.d.) Tips for Coping with Sundowning. https://www.nia.nih.gov/health/tips-coping-sundowning - Take them outside or expose them to bright light in the morning to reset their circadian rhythm. - Do not plan too many activities during the day. A full schedule can be overtiring. - Make early evening a quiet time of day. Play soothing music or ask a family member or friend to call during this time. - Close the curtains or blinds at dusk to minimize shadows and the confusion they may cause. - Reduce noise, clutter, or the number of people in the room. - Do not serve coffee, cola, or other drinks with caffeine late in the day. Aggressive Behaviors Aggressive behaviors may be verbal or physical. They can occur suddenly, with no apparent reason, or result from a frustrating situation. While aggression can be hard to cope with, understanding this is a symptom of Alzheimer’s disease and the person with Alzheimer’s or dementia is not acting this way on purpose can help. See Figure 6.8“5012292106_507e008c7a_o.jpg” by borosjuli is licensed under CC BY 2.0 for an image of a resident with dementia demonstrating aggressive verbal behavior. Aggression can be caused by many factors including physical discomfort, environmental factors, and poor communication. If the person with Alzheimer’s is aggressive, consider what might be contributing to the change in behavior. Physical Discomfort - Is the person able to let you know that he or she is experiencing physical pain? It is not uncommon for persons with Alzheimer’s or other dementias to have urinary tract or other infections. Due to their loss of cognitive function, they are unable to articulate or identify the cause of physical discomfort and, therefore, may express it through physical aggression. - Is the person tired because of inadequate rest or sleep? - Is the person hungry or thirsty? - Are medications causing side effects? Side effects are especially likely to occur when individuals are taking multiple medications for several health conditions. Environmental Factors - Is the person overstimulated by loud noises, an overactive environment, or physical clutter? Large crowds or being surrounded by unfamiliar people — even within one’s own home — can be overstimulating for a person with dementia. - Does the person feel lost? - What time of day is the person most alert? Most people function better during a certain time of day; typically mornings are best. Consider the time of day when making appointments or scheduling activities. Choose a time when you know the person is most alert and best able to process new information or surroundings. Poor Communication - Are your instructions simple and easy to understand? - Are you asking too many questions or making too many statements at once? - Is the person picking up on your own stress or irritability? Techniques for Response There are many therapeutic methods for a nurse or caregiver to respond to aggressive behaviors displayed by a person with dementia. The following are some methods that can be used with aggressive behavior: - Begin by trying to identify the immediate cause of the behavior. Think about what happened right before the reaction that may have triggered the behavior. Rule out pain as the cause of the behavior. Pain can trigger aggressive behavior for a person with dementia. - Focus on the person’s feelings, not the facts. Look for the feelings behind the specific words or actions. - Don’t get upset. Be positive and reassuring and speak slowly in a soft tone. - Limit distractions. Examine the person’s surroundings, and adapt them to avoid future triggers. - Implement a relaxing activity. Try music, massage, or exercise to help soothe the person. - Shift the focus to another activity. The immediate situation or activity may have unintentionally caused the aggressive response, so try a different approach. - Take a break if needed. If the person is in a safe environment and you are able, walk away and take a moment for emotions to cool. - Ensure safety! Make sure you and the person are safe. If these interventions do not successfully calm down the person, seek assistance from others. If it is an emergency situation, call 911 and be sure to tell the responders the person has dementia that causes them to act aggressively. When educating caregivers about responding to aggressive behaviors, encourage them to share their experience with others, such as face-to-face support groups, where they can share response strategies they have tried and also get more ideas from other caregivers. Anxiety and Agitation A person with Alzheimer’s may feel anxious or agitated. They may become restless, causing a need to move around or pace or become upset in certain places or when focused on specific details. See Figure 6.9“old-63622_960_720.jpg” by geralt is licensed under CC0 for an illustration of an older adult feeling the need to move around. Anxiety and agitation can be caused by several medical conditions, medication interactions, or by any circumstances that worsen the person’s ability to think. Ultimately, the person with dementia is biologically experiencing a profound loss of their ability to negotiate new information and stimuli. It is a direct result of the disease. Situations that may lead to agitation can include moving to a new residence or nursing home; changes in environment, such as travel, hospitalization, or the presence of houseguests; changes in caregiver arrangements; misperceived threats; or fear and fatigue resulting from trying to make sense out of a confusing world. Interventions to prevent and treat agitation include the following: - Create a calm environment and remove stressors. This may involve moving the person to a safer or quieter place or offering a security object, rest, or privacy. Providing soothing rituals and limiting caffeine use are also helpful. - Avoid environmental triggers. Noise, glare, and background distraction (such as having the television on) can act as triggers. - Monitor personal comfort. Check for pain, hunger, thirst, constipation, full bladder, fatigue, infections, and skin irritation. Make sure the room is at a comfortable temperature. Be sensitive to the person’s fears, misperceived threats, and frustration with expressing what is wanted. - Simplify tasks and routines. - Find outlets for the person’s energy. The person may be looking for something to do. Provide an opportunity for exercise such as going for a walk or putting on music and dancing. Techniques for Response If a patient with dementia becomes anxious or agitated, consider these potential interventions: - Back off and ask permission before performing care tasks. Use calm, positive statements, slow down, add lighting, and provide reassurance. Offer guided choices between two options when possible. Focus on pleasant events and try to limit stimulation. - Use effective language. When speaking, try phrases such as, “May I help you? Do you have time to help me? You’re safe here. Everything is under control. I apologize. I’m sorry that you are upset. I know it’s hard. I will stay with you until you feel better.” - Listen to the person’s frustration. Find out what may be causing the agitation, and try to understand. - Check yourself. Do not raise your voice, show alarm or offense, or corner, crowd, restrain, criticize, ignore, or argue with the person. Take care not to make sudden movements out of the person’s view. If the person’s anxiety or agitation does not improve using these techniques, notify the provider to rule out physiological causes or medication-related side effects. Hallucinations When a person with dementia experiences hallucinations, they may see, hear, smell, taste, or feel something that isn’t there. Some hallucinations may be frightening, while others may involve ordinary visions of people, situations, or objects from the past. Alzheimer’s and other dementias are not the only cause of hallucinations. Other causes of hallucinations include schizophrenia; physical problems, such as kidney or bladder infections, dehydration, or intense pain; alcohol or drug abuse; eyesight or hearing problems; and medications. See Figure 6.10lewy-body-dementia-2965713_960_720.jpg” by Jetiveri is licensed under CC0 for an illustration of hallucinations experienced by a person with dementia. If a person with dementia begins hallucinating, notify the health care provider to rule out other possible causes and to determine if medication is needed. It may also help to have the person’s eyesight or hearing checked. If these strategies fail and symptoms are severe, medication may be prescribed. While antipsychotic medications can be effective in some situations, they are associated with an increased risk of stroke and death in older adults with dementia and must be used carefully. Techniques for Response When responding to a patient with dementia experiencing hallucinations, be cautious. First, assess the situation and determine whether the hallucination is a problem for the person or for you. Is the hallucination upsetting? Is it leading the person to do something dangerous? Is the sight of an unfamiliar face causing the person to become frightened? If so, react calmly and quickly with reassuring words and a comforting touch. Do not argue with the person about what he or she sees or hears. If the behavior is not dangerous, there may not be a need to intervene. - Offer reassurance. Respond in a calm, supportive manner. You may want to respond with, “Don’t worry. I’m here. I’ll protect you. I’ll take care of you.” Gentle patting may turn the person’s attention toward you and reduce the hallucination. - Acknowledge the feelings behind the hallucination and try to find out what the hallucination means to the individual. You might want to say, “It sounds as if you’re worried” or “This must be frightening for you.” - Use distractions. Suggest a walk or move to another room. Frightening hallucinations often subside in well-lit areas where other people are present. Try to turn the person’s attention to music, conversation, or activities they enjoy. - Respond honestly. If the person asks you about a hallucination or delusion, be honest. For example, if he or she asks, “Do you see the spider on the wall?,” you can respond, “I know you see something, but I don’t see it.” This way you’re not denying what the person sees or hears and avoiding escalating their agitation. - Modify the environment. Check for sounds that might be misinterpreted, such as noise from a television or an air conditioner. Look for lighting that casts shadows, reflections, or distortions on the surfaces of floors, walls, and furniture. Turn on lights to reduce shadows. Cover mirrors with a cloth or remove them if the person thinks that he or she is looking at a stranger. Sundowning Sundowning is increased confusion, anxiety, agitation, pacing, and disorientation in patients with dementia that typically begins at dusk and continues throughout the night. Although the exact cause of sundowning and sleep disorders in people with Alzheimer’s disease is unknown, these changes result from the disease’s impact on the brain. There are several factors that may contribute to sleep disturbances and sundowning: - Mental and physical exhaustion from a full day trying to keep up with an unfamiliar or confusing environment. - An upset in the “internal body clock,” causing a biological mix-up between day and night. - Reduced lighting causing shadows and misinterpretation is seen, causing agitation. - Nonverbal behaviors of others, especially if stress or frustration is present. - Disorientation due to the inability to separate dreams from reality when sleeping. - Decreased need for sleep, a common condition among older adults.Alzheimer’s Association. (2021). https://www.alz.org/ There are several interventions that nurses and caregivers can implement to help manage sleep issues and sundowning: - Promote plenty of rest. - Encourage a regular routine of waking up, eating meals, and going to bed. - When possible and appropriate, include walks or time outside in the sunlight. - Make notes about what happens before sundowning events and try to identify triggers. - Reduce stimulation during the evening hours (e.g., TV, doing chores, loud music, etc.). These distractions may add to the person’s confusion. - Offer a larger meal at lunch and keep the evening meal lighter. - Keep the home environment well-lit in the evening. Adequate lighting may reduce the person’s confusion. - Do not physically restrain the person; it can make agitation worse. - Try to identify activities that are soothing to the person, such as listening to calming music, looking at photographs, or watching a favorite movie. - Take a walk with the person to help reduce his or her restlessness. - Consider the best times of day for administering medication; consult with the prescribing provider or pharmacist as needed. - Limit daytime naps if the person has trouble sleeping at night. - Reduce or avoid alcohol, caffeine, and nicotine that can affect the ability to sleep. - Discuss the situation with the provider when behavioral interventions and environmental changes do not work. Additional medications may be prescribed. Caregiver Role Strain Eighty-three percent of the help provided to people living with dementia in their homes in the United States comes from family members, friends, or other unpaid caregivers. Approximately one quarter of dementia caregivers are also “sandwich generation” caregivers — meaning that they care not only for an aging parent, but also for children under age 18. Dementia can take a devastating toll on caregivers. Compared with caregivers of people without dementia, twice as many caregivers of people with dementia indicate substantial emotional, financial, and physical difficulties.Alzheimer’s Association. (2021). https://www.alz.org/ See Figure 6.11“My_mum_ill_with_dementia_with_me.png” by MariaMagdalens is licensed under CC BY-SA 4.0 of an image of a caregiver daughter caring for her mother with dementia. The caregivers of patients with dementia frequently report experiencing high levels of stress that often eventually impact their health and well-being. Nurses should monitor caregivers for these symptoms of stress: - Denial about the disease and its effect on the person who has been diagnosed. For example, the caregiver might say, “I know Mom is going to get better.” - Anger at the person with Alzheimer’s or frustration that he or she can’t do the things they used to be able to do. For example, the caregiver might say, “He knows how to get dressed — he’s just being stubborn.” - Social withdrawal from friends and activities. For example, the caregiver may say, “I don’t care about visiting with my friends anymore.” - Anxiety about the future and facing another day. For example, the caregiver might say, “What happens when he needs more care than I can provide?” - Depression or decreased ability to cope. For example, the caregiver might say, “I just don’t care anymore.” - Exhaustion that makes it difficult for them to complete necessary daily tasks. For example, the caregiver might say, “I’m too tired to prepare meals.” - Sleeplessness caused by concerns. For example, the caregiver might say, “What if she wanders out of the house or falls and hurts herself?” - Irritability, moodiness, or negative responses. - Lack of concentration that makes it difficult to perform familiar tasks. For example, the caregiver might say, “I was so busy; I forgot my appointment.” - Health problems that begin to take a mental and physical toll. For example, the caregiver might say, “I can’t remember the last time I felt good.” Nurses should monitor for these signs of caregiver stress and provide information about community resources. (See additional information about community resources below.) Caregivers should be encouraged to take good care of themselves by visiting their health care provider, eating well, exercising, and getting plenty of rest. It is helpful to remind them that “taking care of yourself and being healthy can help you be a better caregiver.” It is helpful to teach them relaxation techniques, such as relaxation breathing, progressive muscle relaxation, visualization, and meditation. Caregivers should also be educated about additional care options, such as adult day care, respite care, residential facilities, or hospice care. Adult day centers offer people with dementia and other chronic illnesses the opportunity to be social and to participate in activities in a safe environment, while also giving their caregivers the opportunity to work, run errands, or take a break. Respite care can be provided at home (by a volunteer or paid service) or in a care setting, such as adult day care or residential facility, to provide the caregiver a much-needed break. If the person with Alzheimer’s or other dementia prefers a communal living environment or requires more care than can be safely provided at home, a residential facility may be the best option for providing care. Different types of facilities provide different levels of care, depending on the person’s needs. Hospice care focuses on providing comfort and dignity at the end of life; it involves care and support services that can be of great benefit to people in the final stages of dementia and their families. Read about alternative care options and caregiver support at the Alzheimer Association webpage. Community Resources Local Alzheimer’s Association chapters can connect families and caregivers with the resources they need to cope with the challenges of caring for individuals with Alzheimer’s. - Find a chapter in your community by visiting the Find Your Local Chapter web page. - The Alzheimer’s Association 24/7 Helpline<PHONE_NUMBER>) is available around the clock, 365 days a year. Through this free service, specialists and master’s-level clinicians offer confidential support and information to people living with dementia, caregivers, families, and the public. - The Alzheimer’s Association has a free virtual library web page devoted to resources that increase knowledge about Alzheimer’s and other dementias.Alzheimer’s Association. (2021). https://www.alz.org/ 6.4 Applying the Nursing Process Open Resources for Nursing (Open RN) This section outlines the steps of the nursing process when providing care for adults with cognitive impairments. Assessment Nurses provide care for older adults in a wide variety of settings including acute care facilities, clinics, adult day care facilities, retirement communities, long-term care facilities, private homes, and community-based residential facilities (CBRF). It is vital for nurses to notice any signs of changing mental status based on the patient’s baseline. Any new or sudden changes that indicate possible delirium should be urgently reported to the health care provider for further assessment of potential underlying health conditions. See the following hyperlink to view a delirium evaluation tool used by hospitals. View the Delirium Evaluation Bundle shared by the Agency for Healthcare Research and Quality (AHRQ). When assessing an adult patient with a previously diagnosed cognitive impairment, there are several assessments to include on admission. Their medical history should be reviewed and a medication reconciliation completed. A general survey provides a quick, overall assessment of the way an individual interacts with their environment and their overall mobility status. A comprehensive neurological assessment should be performed to establish a patient’s baseline neurological status. After a baseline status is determined, routine focused neurological assessments are performed to monitor for changes, such as asking the patient to state their name, place, and the date, as appropriate. Read more information about performing a neurological exam in the “Neurological Assessment” chapter of the Open RN Nursing Skills textbook. Additional assessments include functional status and the patient’s ability to perform activities of daily living (ADLs). A decline in the ability to perform self-care and maintain ADLs can affect the individual’s well-being. Functional declines can bring about feelings of inadequacy and lead to depression. The ability to live independently relies on maintenance of self-care skills, including bathing, dressing, and toileting. Other factors that must be considered include the ability to adequately handle finances; maintain a clean, safe environment; and to shop and prepare meals. When deficits in these areas occur, resources should be recommended to assist the individual to meet these needs. Cognitive changes including disorientation, poor judgment, loss of language skill, and memory impairment should be assessed objectively using standardized tools. Common standardized tools used to assess a patient’s mental status include the Mini Mental State Exam (MMSE) and the Mini-Cog.Alzheimer’s Association. (2021). https://www.alz.org/ See Figure 12“InterlockingPentagons.svg” by Jfdwolff[2] is licensed under CC BY-SA 3.0 for an image of one of the questions included on the MMSE. Cultural Considerations Nurses provide culturally competent care for all individuals. Being aware of personal biases related to ageism and cognitive impairments is necessary when providing care for older adults experiencing confusion, memory deficits, and impaired judgment. Ageism is the stereotyping and discrimination against individuals or groups on the basis of their age. Ageism can take many forms, including prejudicial attitudes, discriminatory practices, or institutional policies and practices that perpetuate stereotypical beliefs. Ageism is widely prevalent and stems from the assumption that all members of a group (i.e., older adults) are the same. Ageism has harmful effects on the health of older adults; research has shown that older adults with negative attitudes about aging may live 7.5 years less than those with positive attitudes. Some of this prejudice arises from observable biological declines and may be distorted by awareness of disorders such as dementia, which may be mistakenly thought to reflect normal aging. Socially ingrained ageism can become self-fulfilling by promoting stereotypes of social isolation, physical and cognitive decline, lack of physical activity, and economic burden in older adults.World Health Organization. (2020, November 2). Ageing: Ageism. https://www.who.int/westernpacific/news/q-a-detail/ageing-ageism These biases in health care personnel, patients, and family members can prevent early recognition and treatment of health problems like dementia, delirium, and depression. Diagnoses Commonly used NANDA-I nursing diagnoses for older adults experiencing cognitive impairment include the following: - Self-Care Deficit - Risk for Injury - Impaired Memory - Impaired Coping - Social Isolation A common NANDA-I diagnosis related to cognitive impairment caused by dementia is Self-Care Deficit, defined as, “The inability to independently perform or complete cleansing activities; to put on or remove clothing; to eat; or to perform tasks associated with bowel and bladder elimination.” An associated condition with this nursing diagnosis is “Alteration in cognitive functioning.”Herdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York. An example of a related PES statement is, “Self-Care Deficit related to altered cognitive functioning as evidenced by impaired ability to access the bathroom, to put clothing on lower extremities, and to maintain appearance.” Outcome Identification An example of an overall goal for an older adult experiencing cognitive impairment due to dementia is, “The patient will perform self-care activities within the level of their own ability daily.” An example of a SMART expected outcome for a patient with cognitive impairment resulting in Self Care Deficit is, “The patient will remain free of body odor during their hospital stay.” Planning Interventions There are many nursing interventions that can be implemented for older adults with impaired cognitive function based on their individual needs. Interventions focus on maintaining safety, meeting physical and psychological needs, and promoting quality of life. As always, refer to an evidence-based nursing care planning resource when customizing interventions for specific patients. For interventions targeted for common symptoms of dementia, see the “Alzheimer’s Disease” section in this chapter. See Table 6.4 for general nursing interventions to implement for patients with cognitive impairments. Table 6.4 General Nursing Interventions for Cognitive Impairments \| Therapeutic Communication: Provide nursing care in a timely manner with an attitude of caring and compassion while maintaining the dignity of the individual. Establish a therapeutic relationship based on trust by sitting at the level of the patient and engaging in eye contact. \| \| Reminiscence Therapy: Allow individuals opportunities to share their past experiences and stories. This allows expression of personal identity and supports the individual’s coping and self-esteem. \| \| Touch: When appropriate, touch provides comfort for individuals. It provides sensory stimulation to avoid sensory deprivation and demonstrates caring and warmth. It is important to assess the individual’s reaction to touch before implementing therapeutic gentle touch. \| \| Reality Orientation: This technique provides awareness of person, place, and time for those who are cognitively able. It restores a sense of reality, decreases confusion and disorientation, and promotes a healing environment. Older adults experiencing a change in environment or stressful situation benefit from the use of environmental cues for orientation, such as clocks, calendars, and whiteboards noting who is providing care and when they will return. \| \| Validation Therapy: This technique is used for older adults who are confused. The focus is on the emotional aspect of their communication. This therapy avoids reorientation to time and place, even when incorrect. It does not reinforce incorrect perception but focuses on validating their feelings.Herdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York. \| Implementing Interventions When implementing interventions for patients with cognitive impairments, patient safety receives priority. Implement fall precautions, wandering precautions, and environmental safety precautions as appropriate. Evaluation It is important to routinely evaluate the effectiveness of customized interventions for patients with cognitive impairments. Review the SMART outcomes established for each specific patient to determine if interventions are effectively promoting safety while also maintaining their physiological and psychological needs and promoting quality of life. Modify the care plan when needed to meet these outcome criteria. 6.5 Putting It All Together Patient Scenario Mrs. Vang is an 83-year-old resident that was recently admitted to a long-term memory care facility. She was diagnosed with Alzheimer’s disease last year. She is alert to self but often has periods where she is uncooperative and is unable to follow commands. She has experienced a decline in the ability to provide self-care and wanders and paces at night. She recently fell when wandering outside of her room at night. Applying the Nursing Process Assessment: Mrs. Vang is alert to self only and does not follow commands during the assessment. She is unable to provide self-care despite cueing. Based on the assessment information that has been gathered, the following nursing care plan is created for Mrs. Vang: Nursing Diagnosis: Wandering related to separation from familiar environment as manifested by frequent movement from place to place and pacing. Overall Goal: The patient will remain safe and free from falls. SMART Expected Outcome: Mrs. Vang will experience reduced episodes of wandering within 72 hours. Planning and Implementing Nursing Interventions: The nurse will provide orientation cues, such as family pictures in the patient room, as appropriate. The nurse will encourage a daily routine by all caregivers to prevent discomfort issues related to thirst, hunger, or lack of sleep. The nurse will encourage patient autonomy and provide choices in decisions as appropriate. The nurse will provide opportunities for reminiscence and cultivate therapeutic communication using touch and validation of emotional communication. The nurse will place a bed alarm to alert staff at night when the patient is getting out of bed. The nurse will implement a wander guard ankle bracelet to notify staff if the patient wanders near an exit door. Sample Documentation: Mrs. Vang has impaired thought processes as a result of her Alzheimer’s disease. A care routine has been established. The patient receives appropriate visual cues and reorientation to the environment. Safety interventions have been implemented, and the patient is being monitored for signs of increasing confusion or mental decline. Evaluation: Mrs. Vang has remained safe within the care environment and demonstrated no additional decline in thought processes. Her wandering at night has decreased and the bed alarm alerts staff when she gets out of bed. SMART outcome “met.” 6.6 Learning Activities Open Resources for Nursing (Open RN) Learning Activities (Answers to “Learning Activities” can be found in the “Answer Key” at the end of the book. Answers to interactive activity elements will be provided within the element as immediate feedback.) Practice applying concepts related to cognitive impairments to the following patient scenarios: Scenario A Clara is a 77-year-old female who is admitted to an inpatient acute care center for scheduled hip-replacement surgery. See Figure 6.13 for an image of Clara.“woman-76527_960_720.jpg” by geralt is licensed under CC0 On admission for the surgical procedure, Clara is functionally independent and living at home but reports having some “mild forgetfulness.” The surgery and post-anesthesia recovery period are uneventful, but on postoperative Day 2, she develops severe confusion and agitation. Critical Thinking Questions - What additional assessment data should the nurse collect? - Compare/contrast the symptoms of dementia, delirium, and depression. What condition is the patient exhibiting? What are the possible triggers? - What are priority nursing interventions for the patient at this time? Scenario B Betty is an 82-year-old female resident of a memory care center with a history of moderate Alzheimer’s disease. See Figure 6.14 for an image of Betty in a memory care center.“35528913166_1a61470157_h.jpg” by Senior Guidance is licensed under CC BY 2.0 Staff report that she has episodes of anxiety and agitation that can lead to aggressive behaviors such as yelling, cursing, and waving her cane threateningly at staff members. Critical Thinking Questions - What are the typical symptoms of moderate Alzheimer’s disease? - What assessments should the nurse perform if Betty exhibits anxiety, agitation, or aggressive behavior? - In addition to identifying and eliminating any potential triggers, how should the nurse respond to Betty therapeutically if an episode occurs? - What types of medications may be prescribed for Betty to slow the progression of Alzheimer’s disease? An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=1950#h5p-63 VI Glossary Open Resources for Nursing (Open RN) Adult day centers: Care that offers people with dementia and other chronic illnesses the opportunity to be social and to participate in activities in a safe environment, while also giving their caregivers the opportunity to work, run errands, or take a much-needed break. Ageism: The stereotyping and discrimination against individuals or groups on the basis of their age. Ageism can take many forms, including prejudicial attitudes, discriminatory practices, or institutional policies and practices that perpetuate stereotypical beliefs. Alzheimer’s disease: An irreversible, progressive brain disorder that slowly destroys memory and thinking skills and eventually the ability to carry out the simplest tasks. Cognition: A term used to describe our ability to think. Cognitive impairment: Impairment in mental processes that drive how an individual understands and acts in the world, affecting the acquisition of information and knowledge. Delirium: An acute state of cognitive impairment that typically occurs suddenly due to a physiological cause, such as infection, hypoxia, electrolyte imbalances, drug effects, or other acute brain injury. Dementia: A chronic condition of impaired cognition, caused by brain disease or injury, marked by personality changes, memory deficits, and impaired reasoning. Dementia can be caused by a group of conditions, such as Alzheimer’s disease, vascular dementia, frontal-temporal dementia, and Lewy body disease. It is gradual, progressive, and irreversible. Depression: A brain disorder with a variety of causes, including genetic, biological, environmental, and psychological factors. Growth: Physical changes that occur during the development of an individual beginning at the time of conception. Hospice care: Care that focuses on providing comfort and dignity at the end of life. It involves care and support services that can be of great benefit to people in the final stages of dementia and to their families. Intellectual disability: A diagnostic term that describes intellectual and adaptive functioning deficits identified during the developmental period prior to the age 18. Respite care: Care provided at home (by a volunteer or paid service) or in a care setting, such as adult day centers or residential facilities, that allows the caregiver to take a much-needed break. Sundowning: Increased confusion, anxiety, agitation, pacing, or disorientation in patients with dementia that typically begins at dusk and continues throughout the night. Sensory Impairments VII 7.1 Sensory Impairments Introduction Open Resources for Nursing (Open RN) Learning Objectives - Collect data to identify patients experiencing alterations in sensory perception - Identify factors related to sensory impairments across the life span - Demonstrate respect for the dignity of the patient with a sensory impairment - Detail support for family/significant others caring for patients with a sensory impairment - Include community resources available for patients and families with a sensory impairment - Include adaptations to the environment to maintain safety for the patient with a sensory impairment - Incorporate nursing strategies to maximize sensory perception - Outline nursing interventions for specific sensory disorders - Identify evidence-based practices Our five basic senses of sight (vision), hearing (auditory), touch (tactile), smell (olfactory), and taste (gustatory) help us perceive and act in the world around us. See Figure 7.1“Five_senses.jpg” by Allan-Hermann Pool is licensed under CC BY-SA 4.0 for an illustration of our five senses. We may not often consider the importance of our sensory input. As nurses, we especially rely on our senses when providing patient care as we gather assessment data. We ask questions and listen to patient responses, we listen to their heart and lung sounds, we evaluate the appearance of their skin, we may smell an infectious process when changing a wound dressing, and we feel the sensation of pulses when assessing circulation. When an individual experiences sensory impairment because of the loss of one or more senses or is affected by the amount of stimuli (too much or too little), their ability to safely function is impacted. Nurses identify patients’ sensory impairments and implement interventions to improve their safety, functioning, and quality of life. The nurse’s goal is to provide support and dignity to individuals and their families by using strategies and resources that will help them to engage with their surroundings and others to the best of their ability. This chapter will review common sensory impairments and related nursing care. 7.2 Sensory Impairments Basic Concepts Open Resources for Nursing (Open RN) Interpreting Sensations Before learning about sensory function, it is important to understand how the nervous system works. An intact nervous system is necessary for information to be delivered from the environment to the brain to trigger responses from the body. For neurons to transmit these messages, they are in the form of an action potential. Sensory receptors perceive a stimulus and then change the sensation to an electrical signal so that it can be transmitted to the brain and then out to the body. The signal is transmitted to the brain where it is interpreted, and then signals are quickly sent to the hand to pull away from the hot stimuli.This work is a derivative of StatPearls by Gadhvi & Waseem and is licensed under CC BY 4.0 Our bodies interpret sensations through a process using reception, perception, and reaction. Reception is the first part of the sensory process when a nerve cell or sensory receptor is stimulated by a sensation. Sensory receptors are activated by mechanical, chemical, or temperature stimuli. In addition to our five senses, we also have somatosensation. Somatosensation refers to sensory receptors that respond to stimuli such as pain, pressure, temperature, and vibration. It also includes vestibular sensation, a sense of spatial orientation and balance, and proprioception, the sense of the position of our bones, joints, and muscles. Although these sensory systems are all very different, they share a common purpose. They change a stimulus into an electrical signal that is transmitted in the nervous system.This work is a derivative of Sensory Processes by Lumen Learning and is licensed under CC BY-SA 4.0 The sensory receptors for each of our senses work differently from one another. Light receptors, sound receptors, and touch receptors are each activated by different stimuli with specialized receptor specificity. For example, touch receptors are sensitive to pressure but do not have sensitivity to sound or light. Nerve impulses from sensory receptors travel along pathways to the spinal cord or directly to the brain. Some stimuli are also combined in the brain, such as our sense of smell that can affect our sense of taste.This work is a derivative of Sensory Processes by Lumen Learning and is licensed under CC BY-SA 4.0 As an individual becomes aware of a stimulus and it is transmitted to the brain, perception occurs. Perception is the interpretation of a sensation. All sensory signals, except olfactory system input, are transmitted to the thalamus and to the appropriate region of the cortex of the brain. The thalamus, which is in the forebrain, acts as a relay station for sensory and motor signals. When a sensory signal leaves the thalamus, it is sent to the specific area of the cortex that processes that sense.This work is a derivative of Sensory Processes by Lumen Learning and is licensed under CC BY-SA 4.0 However, conditions that affect a person’s consciousness also affect the ability to perceive and interpret stimuli. Reaction is the response that individuals have to a perception of a received stimulus. The brain determines what sensations are significant because it is impossible to react to all stimuli that are constantly received from our environment. A healthy brain maintains a balance between sensory stimuli received and those reaching awareness. However, sensory overload can occur if the amount of stimuli the brain is receiving is overwhelming to an individual. Sensory deprivation can also occur if there are insufficient sensations from the environment.This work is a derivative of Sensory Processes by Lumen Learning and is licensed under CC BY-SA 4.0 Sensory Impairment Alterations in sensory function include sensory impairment, sensory overload, and sensory deprivation. Sensory impairment includes any type of difficulty that an individual has with one of their five senses. When an individual experiences loss of a sensory function, such as vision, the way they interact with the environment is affected. For example, when an individual gradually loses their vision, their reliance on other senses to receive information from the environment is often enhanced. Safety is always a nursing consideration for a patient with a sensory impairment. Intact senses are required to make decisions about functioning safely within the environment. For example, an individual who has impaired hearing may not be able to hear a smoke alarm and requires visual indicators when the alarm is triggered. Sensory impairments are very common in older adults. Most older adults develop impaired near vision called presbyopia. See Figure 7.2“Pesto ingredients – blurred.jpg” by Colin is licensed under CC BY-SA 4.0 for an image of simulated presbyopia. Deficits in taste and smell are also prevalent in this age group. Additionally, kinesthetic impairment (an altered sense of touch) can occur in adults as young as 55. Kinesthetic impairment can cause difficulty in daily functioning, such as buttoning one’s shirt or performing other fine motor tasks. These sensory losses can greatly impact how older adults live and function.Correia, C., Lopez, K. J., Wroblewski, K. E., Huisingh-Scheetz, M., Kern, D. W., Chen, R. C., Schumm, L. P., Dale, W., McClintock, M. K., & Pinto, J. M. (2016). Global sensory impairment in older adults in the United States. Journal of the American Geriatrics Society, 64(2), 306–313. https://doi.org/10.1111/jgs.13955 Vision Impairments Several types of visual impairments commonly occur in older adults, including macular degeneration, cataracts, glaucoma, diabetic retinopathy, and presbyopia. See Table 7.2 for more information about each of these visual conditions. Table 7.2 Common Visual Conditions \| Macular Degeneration \| Macular degeneration is the leading cause of legal blindness in individuals over 60 years of age. Risk factors include advancing age, a positive family history, hypertension, and smoking. In macular degeneration, there is loss of central vision with classic symptoms such as blurred central vision, distorted vision that causes difficulty driving and reading, and the requirement for brighter lights and magnification for close-up visual activities.Loh, K. Y., & Ogle, J. (2004). Age related visual impairment in the elderly. The Medical Journal of Malaysia, 59(4), 562–569. https://pubmed.ncbi.nlm.nih.gov/15779599/ \| \|---\|---\| \| Cataracts \| Cataracts are the opacity of the lens of the eye that causes clouded, blurred, or dimmed vision. About half of individuals ages 65 to 75 will develop cataracts, with further incidence occurring after age 75. Cataracts can be removed with surgery that replaces the lens with an artificial lens.Loh, K. Y., & Ogle, J. (2004). Age related visual impairment in the elderly. The Medical Journal of Malaysia, 59(4), 562–569. https://pubmed.ncbi.nlm.nih.gov/15779599/ \| \| Glaucoma \| Glaucoma is caused by elevated intraocular pressure that leads to progressive damage to the optic nerve, resulting in gradual loss of peripheral vision. It affects about 4% of individuals over age 70.Loh, K. Y., & Ogle, J. (2004). Age related visual impairment in the elderly. The Medical Journal of Malaysia, 59(4), 562–569. https://pubmed.ncbi.nlm.nih.gov/15779599/ \| \| Diabetic Retinopathy \| Diabetic retinopathy is the leading cause of blindness in adults diagnosed with type 1 and type 2 diabetes mellitus. Diabetic retinopathy is a complication of diabetes mellitus due to damaged blood vessels in the retina causing vision loss.Loh, K. Y., & Ogle, J. (2004). Age related visual impairment in the elderly. The Medical Journal of Malaysia, 59(4), 562–569. https://pubmed.ncbi.nlm.nih.gov/15779599/ Patients with diabetes are encouraged to receive annual eye exams so that retinopathy can be discovered and treated early. Treatments, such as laser treatment that can help shrink blood vessels, injections that can reduce swelling, or surgery, can prevent permanent vision loss.Centers for Disease Control and Prevention. (2018, November 5). Watch out for diabetic retinopathy. https://www.cdc.gov/features/diabetic-retinopathy/index.html \| \| Presbyopia \| As a person ages, the lens of the eye gradually becomes thicker and loses flexibility. It stops focusing light on the retina correctly, causing impaired near vision and accommodation at all distances. Presbyopia starts in the early to mid-forties and worsens with aging. It can lead to significant visual impairment but does not usually cause blindness.Loh, K. Y., & Ogle, J. (2004). Age related visual impairment in the elderly. The Medical Journal of Malaysia, 59(4), 562–569. https://pubmed.ncbi.nlm.nih.gov/15779599/ \| Hearing Loss and Ear Problems Approximately one third of individuals aged 70 and older have hearing loss. Good hearing depends on a series of events that change sound waves in the air into electrical signals. The auditory nerve conducts these electrical signals from the ear to the brain through a series of steps. The structures of the ear, such as the tympanic membrane and cochlea, must be intact and functioning appropriately for conduction of sound to occur. Age-related hearing loss (presbycusis) gradually occurs in most individuals as they age.National Institute on Deafness and Other Communication Disorders. (2018, July 17). Age-related hearing loss. https://www.nidcd.nih.gov/health/age-related-hearing-loss Typically, low-pitched sounds are easiest to hear, but it often becomes increasingly difficult to hear normal conversation, especially over loud background noise. Hearing aids are commonly used to enhance hearing. See Figure 7.3“Traditional_hearing_aids.jpg” by ikesters is licensed under CC BY-SA 2.0 for an image of common hearing aids used to treat hearing loss. Hearing loss can be caused by other factors in addition to aging. A build-up of ear wax in the ear canal can cause temporary hearing loss. Sounds that are too loud or long-term exposure to loud noises can cause noise-induced hearing loss. For example, a loud explosion or employment using loud machinery without ear protection can damage the sensory hair cells in the ear. After these hair cells are damaged, the ability to hear is permanently diminished. Tinnitus, a medical term for ringing in the ears, can also occur. Some medications, such as high doses of aspirin or loop diuretics, can cause toxic effects to the sensory cells in the ear and lead to hearing loss or tinnitus.National Institute on Deafness and Other Communication Disorders. (2018, July 17). Age-related hearing loss. https://www.nidcd.nih.gov/health/age-related-hearing-loss,American Speech-Language-Hearing Association. (n.d.). Causes of hearing loss in adults. https://www.asha.org/public/hearing/causes-of-hearing-loss-in-adults/ In addition to hearing loss, ear problems can also cause problems with balance, dizziness, and vertigo due to vestibular dysfunction. Kinesthetic Impairments Kinesthetic impairments, such as peripheral neuropathy, affect the ability to feel sensations. Symptoms of peripheral neuropathy include sensations of pain, burning, tingling, and numbness in the extremities that decrease a person’s ability to feel touch, pressure, and vibration. Position sense can also be affected and makes it difficult to coordinate complex movements, such as walking, fastening buttons, or maintaining balance when one’s eyes are closed. Peripheral neuropathy is caused by nerve damage that commonly occurs in patients with diabetes mellitus or peripheral vascular disease. It can also be caused by physical injuries, infections, autoimmune diseases, vitamin deficiencies, kidney diseases, liver diseases, and some medications.National Institute of Neurological Disorders and Stroke. (2020, March 16). Peripheral neuropathy fact sheet. https://www.ninds.nih.gov/Disorders/Patient-Caregiver-Education/Fact-Sheets/Peripheral-Neuropathy-Fact-Sheet Life Span Considerations Impaired sensory functioning increases the risk for social isolation in older adults. For example, when individuals are not able to hear well, they may pretend to hear in an attempt to avoid embarrassment when asking for the information to be repeated. They may begin to avoid noisy environments or stop participating socially in conversations around them. Infants and children are also at risk for vision and hearing impairments related to genetic or prenatal conditions. Early determination of sensory impairments is crucial so that problems can be addressed with accommodations to minimize the impact on a child’s development. For example, a screening hearing test is completed on all newborns before discharge to evaluate for hearing impairments that can affect their speech development. Sensory Overload and Sensory Deprivation Stimuli are continually received from a variety of sources in our environment and from within our bodies. When an individual receives too many stimuli or cannot selectively filter out meaningful stimuli, sensory overload can occur. Symptoms of sensory overload include irritability, restlessness, covering ears or eyes to shield them from sensory input, and increased sensitivity to tactile input (i.e., scratchy fabric or sensations of medical equipment).Watson, K. (2018, September 27). What is sensory overload? https://www.healthline.com/health/sensory-overload#causes Sensory overload affects an individual’s ability to interpret stimuli from their environment and can lead to confusion and agitation. See Figure 7.4“Sensory_Overload.jpg” by Stewart Black is licensed under CC BY 2.0 of an image of a patient reacting to sensory overload. The health care environment with its frequent noisy alarms, treatments, staff interruptions, and noisy hallway conversations can cause sensory overload for patients. Individuals have different tolerances for the amount of stimuli that will affect them adversely. Tolerance to stimuli is impacted by factors such as pain, stress levels, sleep patterns, physical health, and emotional health. When sensory overload occurs in a hospitalized patient, it can lead to delirium and acute confusion. It is important for the nurse to limit unnecessary awakenings and interactions with the health care team members when a patient is experiencing sensory overload. Conversely, symptoms of sensory deprivation may occur when there are a lack of stimuli. People experiencing sensory deprivation often report perceptual disturbances such as hallucinations. Symptoms of sensory deprivation can mimic delirium, so it is important for a nurse to further investigate new perceptual disturbances.Mason, O., & Brady, F. (2009). The psychotomimetic effects of short-term sensory deprivation. The Journal of Nervous and Mental Disease, 197(10), 783-785. https://doi.org/10.1097/nmd.0b013e3181b9760b 7.3 Applying the Nursing Process Open Resources for Nursing (Open RN) This section outlines the steps of the nursing process when providing care for individuals with altered sensory function in any setting. Assessment When assessing a patient for sensory impairments, it is important to first establish a therapeutic relationship. Individuals may be hesitant to discuss sensory problems. By establishing a good rapport, patients are more likely to share their sensory concerns and effects on functioning. The health history should include questions regarding current status of sensory function, as well as risk for development of sensory impairment. For example, medications that can be ototoxic should be considered a risk factor for hearing impairment. Additionally, opioids and sedatives depress the central nervous system and can impair stimuli perception and reaction. Techniques to identify deficits in vision, hearing, smell, taste, and sensation are used during the physical exam. Read additional information about assessment techniques using the following hyperlinks. Read about common disorders of the eyes and ears in the “Eye and Ear Assessment” chapter of the Open RN Nursing Skills textbook. Read more about assessing sensory functioning in the “Neurological Assessment” chapter of the Open RN Nursing Skills textbook. There are several factors to consider when assessing a patient’s sensory functioning, such as age, their perception of the impairment, and the impact of the sensory impairment on their daily functioning. Age is an important consideration because many sensory functions can be affected by the aging process. However, it should not be assumed that all sensory problems are a normal part of the aging process. It is important to assess the patient’s perception of sensory impairment and its impact on their functioning, as well for any changes in recent behavior, mental status, emotional status, or cognitive function changes. For example, individuals experiencing hearing loss may be more irritable or anxious and avoid social gatherings due to their hearing impairment. If a patient is experiencing confusion, it is important to evaluate underlying factors that can cause confusion. The environment is also an important consideration when assessing an individual’s sensory functioning. It is important to understand the patient’s daily activities and their ability to perform them; their work and living environment; their use of protective equipment, such as ear protection when working with loud equipment; and their adherence with routine screenings, such as vision and hearing exams. Individuals with sensory impairments are at increased risk for falls and injury, so it is important to encourage basic safety features in the environment, including adequate lighting, availability of handrails and grab bars, hazard-free walkways, and appropriate settings on water heater controls. When sensory impairments are identified, they should be documented in the patient’s chart and communicated to collaborative team members working with the individual. For example, when an individual has a hearing impairment, it is important to consider their alternative communication needs. They may use lipreading and require face-to-face views when communicating. The use of assistive devices for sensory functioning, such as glasses and hearing aids, should also be documented and communicated. It is important to ensure proper functioning of the devices for optimal patient outcomes. In fact, a hospitalized older adult is at greater risk for developing delirium when their typical glasses and hearing aids (i.e., their “eyes and ears”) are not available, causing sensory deprivation. See Table 7.3a for a comparison of expected versus unexpected findings on assessment, including those that require notification of the health care provider. Table 7.3a Expected Versus Unexpected Findings \| Assessment \| Expected Findings \| Unexpected Findings \| \|---\|---\|---\| \| Hearing and Ears: Assess ability to appropriately answer questions individually and in a group setting. Assess the ear canal for excess cerumen. Perform a whisper test while standing behind the seated patient. Observe the patient’s balance and gait. \| The patient can converse and answer questions. Presbycusis can occur with aging. \| Inability to communicate; complaints of ringing in ears (tinnitus), decreased attention, and withdrawal from conversations. Poor coordination, loss of proprioception, increased falls. Report to the health care provider recent changes in hearing, new tinnitus, imbalance, or dizziness. \| \| Vision: Assess near vision by the ability to read printed material. Use the Snellen chart to assess distant vision. In a long-term care or home setting, observe the patient’s ability to perform ADLs. \| Around age 40, reading glasses may become necessary for close work. \| Report to the health care provider new changes in vision. \| \| Touch: Assess ability to feel stimuli by lightly touching the extremities, bottom of the feet, and fingers. Ask if the patient has unusual sensations in their extremities (e.g., tingling, burning, pain). \| The patient can feel light touch and discriminate between warm and cold. \| Inability to feel light touch; reported new numbness, tingling, or pain in the extremities. Report to the health care provider sudden changes in sensation or peripheral neuropathy or new onset of facial numbness (such as in the case of a cerebrovascular accident, commonly referred to as a stroke). \| \| Smell: Assess ability to identify odors with eyes closed. \| The patient can identify smells such as vanilla, lemon, or coffee. The sense of smell often diminishes with advancing age. \| Inability to differentiate odors or decreased sensitivity to strong odors. \| \| Taste: Ask about food intake and taste. \| The patient can determine if food is salty, sweet, or spicy. \| Inability to discriminate taste, leading to changes in appetite, weight loss, excess use of salt or sugar, and depression. \| \| Sensory Input: Assess for cognitive, perceptual, and affective changes. \| Sensory stimulation is adequate to maintain awareness. \| Irritability, restlessness, covering ears or eyes to shield themselves from sensory input, increased sensitivity to tactile input. Reduced learning capacity or inability to think. Confusion, boredom, changes in visual/motor coordination. Report to health care provider sudden changes in cognitive, perceptual, or affective abilities. \| Diagnoses Commonly used NANDA-I nursing diagnoses for patients experiencing alterations in sensory function include the following:Herdman, T., & Kamitsuru, S. (2017). NANDA international nursing diagnoses: Definitions & classification 2018-2020 (11th ed.). Thieme Publishers. pp. 114, 393. - Risk for Injury - Risk for Falls - Impaired Verbal Communication - Social Isolation A common NANDA diagnosis related to sensory alterations is Risk for Injury, which is defined as, “Susceptible to physical damage due to environmental conditions interacting with the individual’s adaptive and defensive resources, which may compromise health.” “Alteration in sensation” is an associated condition for this nursing diagnosis. For risk diagnoses, there are no related factors (etiological factors) because you are identifying a vulnerability in a patient for a potential problem that is not yet present. Additionally, the nurse cannot resolve sensory alteration, so it should not be listed as a related factor to which interventions are directed. Instead, the phrase “as evidenced by” is used to refer to the evidence of risk that exists. Therefore, a sample NANDA-I diagnosis in current PES format would be as follows: “Risk for Injury as evidenced by alteration in vision.” Outcomes An overall goal for a patient at risk for injury related to alteration in sensation is as follows: - The patient will remain free from injury. An example of a “SMART” expected outcome for a patient with impaired vision is as follows: - The patient will be able to verbalize the layout of the room within four hours of admission. Planning Interventions There are many nursing interventions that can be implemented for individuals with impaired sensory function. To assist patients to communicate effectively and to promote their quality of life, it is important for the nurse to customize appropriate interventions based on their individual needs. As always, refer to an evidence-based nursing care planning resource when customizing interventions for specific patients. See Table 7.3b for basic nursing interventions to implement for a variety of sensory alterations.Butcher, H., Bulechek, G., Dochterman, J., & Wagner, C. (2018). Nursing Interventions Classification (NIC). Elsevier. pp. 115-117. Table 7.3b Nursing Interventions to Address Sensory AlterationsButcher, H., Bulechek, G., Dochterman, J., & Wagner, C. (2018). Nursing Interventions Classification (NIC). Elsevier. pp. 115-117. \| Sensory Alteration \| Nursing Interventions \| \| Impaired Vision \| Ensure that patients have access to their glasses or contacts that are cleaned properly and have a current prescription. Provide magnifying glasses if needed. Identify yourself whenever entering the room. Monitor functional implications of diminished vision. Provide adequate room lighting. Minimize glare (i.e., offer sunglasses or draw the window covering). Describe the environment to the patient as needed. Avoid rearranging the environment. Maintain an uncluttered environment and remove hazards such as scatter rugs and oxygen tubing when possible. Provide verbal explanations of the location of items or food. Provide reading materials in large print, as needed. Apply labels to frequently used items (e.g., mark medication bottles using high-contrasting colors). Encourage and assist in arranging annual eye exams, including screening for glaucoma. \| \|---\|---\| \| Hearing Impairment \| Perform or arrange for routine hearing assessments. Assist the patient in acquiring a hearing aid or assistive hearing device when needed. Ensure appropriate use of assistive hearing aids as needed; maintain batteries and cleanliness of the equipment. Gain patient’s attention before speaking. Avoid noisy background environments when speaking. Avoid communicating more than 2-3 feet away from the patient. Use gestures, when necessary. Simplify language (i.e., do not use slang but do use short, simple sentences) as appropriate. Facilitate lipreading by facing the patient directly in good lighting, allowing them to see your mouth while speaking. Avoid speaking with anything in your mouth (such as gum or a mint) and do not turn from them while speaking. Use a low, deep voice when speaking. For patients with severe hearing impairment, document their preferred method of communication (e.g., verbal, written, lipreading, or American Sign Language) in their plan of care. \| \| Impaired Sensitivity to Odor \| Advise the patient to check pilot lights in home appliances visually. Encourage the patient to check expiration dates on food items and marking dates on leftovers in the refrigerator. \| \| Impaired Tactile Sensation \| Maintain water heater temperature at a safe range to avoid burns. Check the temperature of bath water with a thermometer. \| \| Impaired Oral Communication \| Listen to the patient and provide sufficient time for their answer. Avoid childlike phrases and words. Ask questions that only require short or “yes” or “no” answers for patients with expressive aphasia. Keep explanations simple. Provide a communication board or other alternative methods of communication as appropriate. Collaborate with a speech therapist to develop a plan for effective communication. Provide education to family/caregivers to facilitate communication. \| \| Sensory Overload \| Plan and combine nursing activities to avoid interrupting rest time. Decrease noise level in the room and the hallway outside as much as possible, including both noises from medical devices and conversations. Close the room door if possible. \| \| Sensory Deprivation \| Provide meaningful stimuli such as the patient’s choice of television, radio, reading material, calendars, photos of family members, and pets. Provide social interaction as appropriate; encourage family members/caregivers to engage in meaningful conversations with individuals. \| Standards of Care National Patient Safety Goals established by The Joint Commission include prevention of falls. Appropriately assessing the risk of falls for patients with sensory impairments and implementing effective nursing interventions to prevent falls help to meet this standard of care.The Joint Commission. (n.d.). 2021 National patient safety goals. https://www.jointcommission.org/standards/national-patient-safety-goals/ Evaluation Evaluate a patient’s progress toward the expected outcomes established. Include safety, functioning, ability to communicate, and satisfaction with quality of life when evaluating the effectiveness of interventions. Determine if changes in the plan of care are needed to better meet the needs of the individual. 7.4 Putting It All Together Open Resources for Nursing (Open RN) Review how to apply the nursing process for a patient with impaired sensation in the following scenario. Patient Scenario Mr. Mitchell, age 87, is accompanied to the primary care clinic with his daughter Elise. See Figure 7.5“man-old-confused-angry-thinker-street-in-the-age-people-tourists.jpg” by unknown is in the Public Domain for a simulated image of Mr. Mitchell. Elise tells the nurse that her father has been increasingly withdrawn and she has difficulty getting in contact with him during the week by phone. She is concerned that he is experiencing depression. Mr. Mitchell is alert, well-groomed, and smiling. As the nurse begins the initial assessment interview, it is noted that Mitchell smiles and nods a lot, but does not answer direct questions appropriately. Elise has shared that she has not noted problems with her father’s ability to care for himself; he is paying his own bills and orders groceries online for delivery. When questioned further about his answers, Mr. Mitchell admits that he is unsure what was asked of him. He is embarrassed about this and avoids asking people to repeat themselves. He also explains that his father had a hearing device, and it always “rang loudly” so he has not considered this option. The nurse performs a whisper test and discovers he is unable to report any of the six words whispered behind him. She notes that Mr. Mitchell is interested in improving his ability to hear and participate in conversations with others. Applying the Nursing Process Assessment: The nurse performs a whisper test and discovers he is unable to report any of the six words whispered behind him. He is interested in improving his ability to hear and participate in conversations with others. Based on the interview and assessment information, the following nursing care plan is created for Mr. Mitchell. Nursing Diagnosis: Readiness for Enhanced Communication as evidenced by expressed desire to enhance hearing and communication. Overall Goal: The patient will experience enhanced communication with improved hearing. SMART Expected Outcome: Mr. Mitchell will attend an appointment arranged with an audiologist within two weeks. Planning and Implementing Nursing Interventions The nurse provides education about available hearing devices and encourages the patient to attend an appointment with an audiologist. While speaking to the patient, she faces him directly and provides good lighting so that he can read her lips. She shuts the door to the exam room to provide a quiet environment and uses short, simple sentences. She does not interpret nodding to indicate understanding. She shares her assessment findings with the provider and requests a referral to an audiologist and then assists the patient in making the appointment. She asks the patient and his daughter if they have any questions before they leave the clinic. Sample Documentation During the intake interview, the patient did not answer questions inappropriately or did not answer at all. Exhibited embarrassment when asking people to repeat their statements. Daughter states, “He is becoming increasingly withdrawn.” Ear canals are clear without cerumen present. Unable to report six out of six words during the whisper test. Provided brief explanation of new technology available for hearing loss while standing directly in front of the patient, and he appeared to be able to slightly read lips. Encouraged consultation with an audiologist and notified the provider of assessment findings. Appointment made with the audiologist and communicated place, date, and time to the patient and his daughter. Evaluation During the next clinic appointment in two weeks, Mr. Mitchell is wearing a hearing aid device and answers questions appropriately. He reports that he has been attending more social events “now that I can hear better.” The SMART outcome was “met.” 7.5 Learning Activities Open Resources for Nursing (Open RN) Learning Activities (Answers to “Learning Activities” can be found in the “Answer Key” at the end of the book. Answers to interactive activity elements will be provided within the element as immediate feedback.) Practice Activity Data Collection/Assessment - Working with a partner or a “simulated patient,” use the following questions and actions listed to perform a sensory function assessment. Use critical thinking to ask as-needed follow up questions. Vision: - Do you wear glasses or contact lenses? - Do you have problems reading or doing close work? Do you have problems seeing far away objects? - Do you have any floaters in your vision (spots)? - When have you last had your eyes examined by an eye doctor? - Is there a family history of glaucoma or other eye diseases? - Have you ever had eye trauma or surgery? - Read words from a book or newspaper. Hearing: - Do you currently have any ear pain, discharge, or hearing changes? - Do you note yourself having trouble hearing in certain situations? - Do you note any dizziness or ringing in your ears (tinnitus)? - Do you work in an environment where you are exposed to loud noise on a regular basis? Do you wear protection on your ears from the noise? - Have you taken any medications that came with a warning to report any changes in hearing? - Have family members or friends mentioned that you seem not to hear? - Perform the whisper test. Smell: - How is your sense of smell? - Identify some scents like coffee or lemons with eyes closed. Touch: - Are you able to feel when someone is touching you? - Do you have unusual sensations or numbness and tingling? - Identify an object with eyes closed like a key. Taste: - Have you noted any changes in your ability to taste foods? - Is your appetite “normal” for you? Have you noted a decrease? - Taste and identify a food like sugar or salt. Analysis and Care Planning 2. Create a nursing diagnoses based on your assessment findings. 3. Identify a patient-centered goal and SMART expected outcomes. 4. Outline nursing interventions to help the patient to meet the established goal and expected outcome. An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=516#h5p-64 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=516#h5p-18 VII Glossary Open Resources for Nursing (Open RN) Cataracts: Opacity of the lens of the eye that causes clouded, blurred, or dim vision. Cataracts can be removed with surgery that replaces the lens with an artificial lens. Diabetic retinopathy: A complication of diabetes mellitus due to damaged blood vessels in the retina. If found early, treatments, such as laser treatment that can help shrink blood vessels, injections that can reduce swelling, or surgery, can prevent permanent vision loss. Glaucoma: Gradual loss of peripheral vision caused by elevated intraocular pressure that leads to progressive damage to the optic nerve. Kinesthetic impairment: An altered sense of touch that can cause difficulty in performing fine motor tasks. Macular degeneration: Loss of central vision with symptoms such as blurred central vision, distorted vision that causes difficulty driving and reading, and the requirement for brighter lights and magnification for close-up visual activities. Perception: The interpretation of sensation during the sensory process. Presbycusis: Age-related hearing loss. Presbyopia: The impairment of near vision and accommodation as the lens of the eye gradually becomes thicker and loses flexibility as a person ages. Proprioception: The sense of the position of our bones, joints, and muscles. Reaction: The response that individuals have to a perception of a received stimulus. Reception: The initial part of the sensory process when a nerve cell or sensory receptor is stimulated by a sensation. Sensory deprivation: A condition that occurs when there is a lack of sensations due to sensory impairments or when the environment has few quality stimuli. Sensory impairment: Any type of difficulty that an individual has with one of their five senses or sensory function. Sensory overload: A condition that occurs when an individual receives too many stimuli or cannot selectively filter meaningful stimuli. Somatosensation: Sensory receptors that respond to specific stimuli such as pain, pressure, temperature, and vibration; includes vestibular sensation and proprioception. Tinnitus: Hearing ringing in the ears. Vestibular sensation: A sense of spatial orientation and balance. Oxygenation VIII 8.1 Oxygenation Introduction Open Resources for Nursing (Open RN) Learning Objectives - Assess the patient for objective and subjective manifestations of impaired oxygenation - Distinguish normal and abnormal assessment data - Adapt care based on oxygenation assessment data - Interpret diagnostic tests and lab values indicative of a disturbance in oxygenation - Identify evidence-based practices Sufficient oxygenation is vital to maintain life. When prioritizing nursing interventions, we often refer to using the “ABCs,” an acronym used to signify the importance of maintaining a patient’s airway, breathing, and circulation. Several body systems work collaboratively during the oxygenation process to take in oxygen from the air, carry it through the bloodstream, and adequately oxygenate tissues. It is important that all parts of the system work together to ensure that oxygen is delivered appropriately to tissues within each system. Any alteration in these systems can have catastrophic implications on a patient’s health. First, the airway must be open and clear. The chest and lungs must mechanically move air in and out of the lungs. The bronchial airways must be open so that air can reach the alveoli, where the exchange of oxygen and carbon dioxide occurs. The heart must effectively pump oxygenated blood from the lungs and through the systemic arteries. There must be adequate amounts of hemoglobin in the blood to sufficiently carry the oxygen molecules to the tissues. However, several medical conditions such as asthma, chronic obstructive pulmonary disease (COPD), pneumonia, heart disease, and anemia can impair the body’s ability to effectively complete this oxygenation process.This work is a derivative of Nursing Skills by Open RN licensed under CC BY 4.0 This chapter will review these basic concepts related to oxygenation and apply the nursing process to patients who are experiencing alterations in oxygenation. 8.2 Oxygenation Basic Concepts Open Resources for Nursing (Open RN) Several body systems contribute to a person’s oxygenation status, including the respiratory, cardiovascular, and hematological systems. These systems are reviewed in the following sections. Respiratory System The main function of our respiratory system is to provide the body with a constant supply of oxygen and to remove carbon dioxide. To achieve these functions, muscles and structures of the thorax create the mechanical movement of air into and out of the lungs called ventilation. Gas exchange occurs at the alveolar level where blood is oxygenated and carbon dioxide is removed, which is called respiration. Several respiratory conditions can affect a patient’s ability to maintain adequate ventilation and respiration, and there are several medications used to enhance a patient’s oxygenation status. Use the following hyperlinks to review information regarding the anatomy and physiology of the respiratory system, common respiratory conditions, and classes of respiratory medications. Read additional information about the “Respiratory System” in Open RN Nursing Pharmacology or use the following hyperlinks to go to specific subsections of the chapter: - - Review the anatomy and physiology of the respiratory system. - Learn about common respiratory disorders. - Read about common respiratory medications . Cardiovascular System In order for oxygenated blood to move from the alveoli in the lungs to the various organs and tissues of the body, the heart must adequately pump blood through the systemic arteries. The amount of blood that the heart pumps in one minute is referred to as cardiac output. The passage of blood through arteries to an organ or tissue is referred to as perfusion. Several cardiac conditions can adversely affect cardiac output and perfusion in the body. There are several medications used to enhance a patient’s cardiac output and maintain adequate perfusion to organs and tissues throughout the body. Use the following hyperlinks to review information regarding the anatomy and physiology of the cardiovascular system, common cardiac disorders, and various cardiovascular system medications. Read additional information about the cardiovascular system in the “Cardiovascular & Renal” chapter in Open RN Nursing Pharmacology or use the following hyperlinks to go to specific subsections of this chapter: - Review the anatomy and physiology of the cardiovascular system. - Learn about common cardiac disorders. - Read about common cardiovascular system medications. Hematological System Although the bloodstream carries small amounts of dissolved oxygen, the majority of oxygen molecules are transported throughout the body by attaching to hemoglobin within red blood cells. Each hemoglobin protein is capable of carrying four oxygen molecules. When all four hemoglobin structures contain an oxygen molecule, it is referred to as “saturated.”This work is a derivative of Anatomy & Physiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/anatomy-and-physiology/pages/1-introduction See Figure 8.1“2322_Fig_23.33-a.jpg” by OpenStax is licensed under CC BY 3.0 for an image of hemoglobin protein within a red blood cell with four sites for carrying oxygen molecules. When oxygenated blood reaches tissues within the body, oxygen is released from the hemoglobin, and carbon dioxide is picked up and transported to the lungs for release on exhalation. Carbon dioxide is transported throughout the body by three major mechanisms: dissolved carbon dioxide, attachment to water as HCO3-, and attachment to the hemoglobin in red blood cells.This work is a derivative of Anatomy & Physiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/anatomy-and-physiology/pages/1-introduction See Figure 8.2“2325_Carbon_Dioxide_Transport.jpg” by OpenStax is licensed under CC BY 3.0 for an illustration of carbon dioxide transport.This work is a derivative of Anatomy & Physiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/anatomy-and-physiology/pages/1-introduction Measuring Oxygen, Carbon Dioxide, and Acid Base Levels Because the majority of oxygen transported in the blood is attached to hemoglobin, a patient’s oxygenation status is easily assessed using pulse oximetry, referred to as SpO2. See Figure 8.3“OxyWatch_C20_Pulse_Oximeter.png” by Thinkpaul is licensed under CC BY-SA 3.0 for an image of a pulse oximeter. This reading refers to the amount of hemoglobin that is saturated. The target range of SpO2 for an adult is 94-98%.This work is a derivative of StatPearls by Patel, Miao, Yetiskul, and Majmundar and is licensed under CC BY 4.0 For patients with chronic oxygenation conditions such as COPD, the target range for SpO2 is often lower at 88% to 92%. Although SpO2 is an efficient, noninvasive method for assessing a patient’s oxygenation status, it is not always accurate. For example, if a patient is severely anemic, the patient has a decreased amount of hemoglobin in the blood available to carry the oxygen, which subsequently affects the SpO2 reading. Decreased perfusion of the extremities can also cause inaccurate SpO2 levels because less blood delivered to the tissues causes a false low SpO2. Additionally, other substances can attach to hemoglobin such as carbon monoxide, causing a falsely elevated SpO2. A more specific measurement of oxygen and carbon dioxide in the blood is obtained using an arterial blood gas (ABG). ABG results are often used for patients who have deteriorating or unstable respiratory status requiring emergency treatment. An ABG is a blood sample that is typically drawn from the radial artery by a respiratory therapist. ABG results indicate oxygen, carbon dioxide, pH, and bicarbonate levels. The partial pressure of oxygen in the arterial blood is referred to as PaO2. PaO2 measures the pressure of oxygen dissolved in the arterial blood and how well oxygen is able to move from the lungs into the blood. The normal PaO2 level of a healthy adult is 80 to 100 mmHg. The PaO2 reading is more accurate than a SpO2 reading because it is not affected by hemoglobin levels. The partial pressure of carbon dioxide in the arterial blood is the PaCO2 level. The PaCO2 level measures the pressure of carbon dioxide dissolved in the blood and how well carbon dioxide is able to move out of the body. It is typically used to determine if sufficient ventilation is occurring at the alveolar level. The normal PaCO2 level of a healthy adult is 35-45 mmHg. The normal range of pH level for arterial blood is 7.35-7.45, and the normal range for the bicarbonate (HCO3-) level is 22-26. The SaO2 level is also calculated in ABG results, which is the calculated arterial oxygen saturation level.This work is a derivative of StatPearls by Castro and Keenaghan and is licensed under CC BY 4.0 Hypoxia and Hypercapnia Hypoxia is defined as a reduced level of tissue oxygenation. Hypoxia has many causes, ranging from respiratory and cardiac conditions to anemia. Hypoxemia is a specific type of hypoxia that is defined as decreased partial pressure of oxygen in the blood (PaO2) indicated in an arterial blood gas (ABG) result. Early signs of hypoxia are anxiety, confusion, and restlessness. As hypoxia worsens, the patient’s level of consciousness and vital signs will worsen with an increased respiratory rate and heart rate and decreased pulse oximetry readings. Late signs of hypoxia include bluish discoloration of the skin and mucous membranes called cyanosis. See Figure 8.4“Cynosis.JPG” by James Heilman, MD is licensed under CC BY-SA 3.0 for an image of cyanosis. Hypercapnia, also referred to as hypercarbia, is an elevated level of carbon dioxide in the blood. This level is measured by the PaCO2 level in an ABG test and is indicated when the PaCO2 level is greater than 45. Hypercapnia is caused by hypoventilation or when the alveoli are ventilated but not perfused. In a state of hypercapnia, the accumulation of carbon dioxide in the blood causes the pH of the blood to drop, leading to a state of respiratory acidosis. You can read more about respiratory acidosis in the “Acid-Base Balance” section of the “Fluids and Electrolytes” chapter. Patients with hypercapnia have symptoms such as tachycardia, dyspnea, flushed skin, confusion, headaches, and dizziness. If the hypercapnia develops gradually over time, symptoms may be mild or may not be present at all. Hypercapnia is managed by addressing its underlying cause. A noninvasive positive pressure device such as a BiPAP may be used to help eliminate the excess carbon dioxide, but if this is not sufficient, intubation may be required.This work is a derivative of StatPearls by Patel, Miao, Yetiskul, and Majmundar and is licensed under CC BY 4.0 You can read more about BiPAP devices and intubation in the “Oxygen Therapy” chapter in Open RN Nursing Skills. It is important for a nurse to recognize early signs of respiratory distress and report changes in patient condition to prevent respiratory failure. See Table 8.2a for symptoms and signs of respiratory distress.This work is a derivative of Clinical Procedures for Safer Patient Care by British Columbia Institute of Technology and is licensed under CC BY 4.0 Table 8.2a Symptoms and Signs of Respiratory Distress \| Signs and Symptoms \| Description \| \|---\|---\| \| Shortness of breath (Dyspnea) \| Dyspnea is a subjective symptom of not getting enough air. Depending on severity, dyspnea causes increased levels of anxiety. \| \| Restlessness \| An early sign of hypoxia. \| \| Tachycardia \| An elevated heart rate (above 100 beats per minute in adults) can be an early sign of hypoxia. \| \| Tachypnea \| An increased respiration rate (above 20 breaths per minute in adults) is an indication of respiratory distress. \| \| Oxygen saturation level (SpO2) \| Oxygen saturation levels should be above 94% for an adult without an underlying respiratory condition. \| \| Use of accessory muscles \| Use of neck or intercostal muscles when breathing is an indication of respiratory distress. \| \| Noisy breathing \| Audible noises with breathing are an indication of respiratory conditions. Further assess lung sounds with a stethoscope for adventitious sounds such as wheezing, rales, or crackles. Secretions can plug the airway, thereby decreasing the amount of oxygen available for gas exchange in the lungs. \| \| Flaring of nostrils \| Nasal flaring is a sign of respiratory distress, especially in infants. \| \| Skin color (Cyanosis) \| Bluish changes in skin color and mucus membranes is a late sign of hypoxia. \| \| Position of patient \| Patients in respiratory distress often automatically sit up and lean over by resting arms on their legs, referred to as the tripod position. The tripod position enhances lung expansion. Conversely, patients who are hypoxic often feel worse dyspnea when lying flat in bed and avoid the supine position. \| \| Ability of patient to speak in full sentences \| Patients in respiratory distress may be unable to speak in full sentences or may need to catch their breath between sentences. \| \| Confusion or change in level of consciousness (LOC) \| Confusion can be an early sign of hypoxia and changing level of consciousness is a worsening sign of hypoxia. \| Treating Hypoxia and Hypercapnia Hypoxia and/or hypercapnia are medical emergencies and should be treated promptly by calling for assistance as indicated by agency policy. Failure to initiate oxygen therapy when needed can result in serious harm or death of the patient. Although oxygen is considered a medication that requires a prescription, oxygen therapy may be initiated without a physician’s order in emergency situations as part of the nurse’s response to the “ABCs,” a common abbreviation for airway, breathing, and circulation. Most agencies have a protocol in place that allows nurses to apply oxygen in emergency situations and obtain the necessary order at a later time.This work is a derivative of Clinical Procedures for Safer Patient Care by British Columbia Institute of Technology and is licensed under CC BY 4.0 In addition to administering oxygen therapy, there are several other interventions a nurse can implement to assist an hypoxic patient. Additional interventions used to treat hypoxia in conjunction with oxygen therapy are outlined in Table 8.2b. Table 8.2b Interventions to Manage Hypoxia \| Interventions \| Additional Information \| \|---\|---\| \| Raise the head of the bed. \| Raising the head of the bed to high Fowler’s position promotes effective chest expansion and diaphragmatic descent, maximizes inhalation, and decreases the work of breathing. \| \| Use tripod positioning. \| Situate the patient in a tripod position. Patients who are short of breath may gain relief by sitting upright and leaning over a bedside table while in bed, which is called a three-point or tripod position. \| \| Encourage enhanced breathing and coughing techniques. \| Enhanced breathing and coughing techniques such as using pursed-lip breathing, coughing and deep breathing, huffing technique, incentive spirometry, and flutter valves may assist patients to clear their airway while maintaining their oxygen levels. See the “Enhanced Breathing and Coughing Techniques” section below for additional information regarding these techniques. \| \| Manage oxygen therapy and equipment. \| If the patient is already on supplemental oxygen, ensure the equipment is turned on, set at the required flow rate, and is properly connected to an oxygen supply source. If a portable tank is being used, check the oxygen level in the tank. Ensure the connecting oxygen tubing is not kinked, which could obstruct the flow of oxygen. Feel for the flow of oxygen from the exit ports on the oxygen equipment. In hospitals where medical air and oxygen are used, ensure the patient is connected to the oxygen flow port. Various types of oxygenation equipment are prescribed for patients requiring oxygen therapy. Oxygenation equipment is typically managed in collaboration with a respiratory therapist in hospital settings. Equipment includes devices such as nasal cannula, masks, Continuous Positive Airway Pressure (CPAP), Bilevel Positive Airway Pressure (BiPAP), and mechanical ventilators. For more information, see the “Oxygenation Equipment” section of the “Oxygen Therapy” chapter in Open RN Nursing Skills. \| \| Assess the need for respiratory medications. \| Pharmacological management is essential for patients with respiratory disease such as asthma, COPD, or severe allergic response. Bronchodilators effectively relax smooth muscles and open airways. Glucocorticoids relieve inflammation and also assist in opening air passages. Mucolytics decrease the thickness of pulmonary secretions so that they can be expectorated more easily. \| \| Provide suctioning, if needed. \| Some patients may have a weakened cough that inhibits their ability to clear secretions from the mouth and throat. Patients with muscle disorders or those who have experienced a stroke (i.e., cerebral vascular accident) are at risk for aspiration, which could lead to pneumonia and hypoxia. Provide oral suction if the patient is unable to clear secretions from the mouth and pharynx. See the “Tracheostomy Care and Suctioning” chapter in Open RN Nursing Skills for additional details on suctioning. \| \| Provide pain relief, If needed. \| Provide adequate pain relief if the patient is reporting pain. Pain increases anxiety and metabolic demands, which, in turn, increase the need for more oxygen supply. \| \| Consider side effects of pain medication. \| A common side effect of pain medication is respiratory depression. For more information about managing respiratory depression, see the “Pain Management” section of the “Comfort” chapter. \| \| Consider other devices to enhance clearance of secretions. \| Chest physiotherapy and specialized devices assist with secretion clearance, such as handheld flutter valves or vests that inflate and vibrate the chest wall. Consult with a respiratory therapist as needed based on the patient’s situation. \| \| Plan frequent rest periods between activities. \| Plan interventions for patients with dyspnea so they can rest frequently and decrease oxygen demand. \| \| Consider other potential causes of dyspnea. \| If a patient’s level of dyspnea is worsening, assess for other underlying causes in addition to the primary diagnosis. For example, are there other respiratory, cardiovascular, or hematological conditions occurring? Start by reviewing the patient’s most recent hemoglobin and hematocrit lab results, as well as any other diagnostic tests such as chest X-rays and ABG results. Completing a thorough assessment may reveal abnormalities in these systems to report to the health care provider. \| \| Consider obstructive sleep apnea. \| Patients with obstructive sleep apnea (OSA) are often not previously diagnosed prior to hospitalization. The nurse may notice the patient snores, has pauses in breathing while snoring, has decreased oxygen saturation levels while sleeping, or awakens feeling not rested. These signs may indicate the patient is unable to maintain an open airway while sleeping, resulting in periods of apnea and hypoxia. If these apneic periods are noticed but have not been previously documented, the nurse should report these findings to the health care provider for further testing and follow-up. A prescription for a CPAP or BiPAP device while sleeping may be needed to prevent adverse outcomes. \| \| Monitor patient’s anxiety. \| Assess patient’s anxiety. Anxiety often accompanies the feeling of dyspnea and can worsen it. Anxiety in patients with COPD is chronically undertreated. It is important for the nurse to address the feelings of anxiety in addition to the feelings of dyspnea. Anxiety can be relieved by teaching enhanced breathing and coughing techniques, encouraging relaxation techniques, or administering antianxiety medications. \| Enhanced Breathing and Coughing Techniques In addition to oxygen therapy and the interventions listed in Table 8.2b, there are several techniques a nurse can teach a patient to use to enhance their breathing and coughing. These techniques include pursed-lip breathing, incentive spirometry, coughing and deep breathing, and the huffing technique. Additionally, vibratory positive expiratory pressure (PEP) therapy can be incorporated in collaboration with a respiratory therapist. Pursed-lip Breathing Pursed-lip breathing is a technique that decreases dyspnea by teaching people to control their oxygenation and ventilation. See Figure 8.5“v4-460px-Live-With-Chronic-Obstructive-Pulmonary-Disease-Step-8.jpg” by unknown is licensed under CC BY-SA 3.0. Access for free at https://www.wikihow.com/Live-With-Chronic-Obstructive-Pulmonary-Disease for an illustration of pursed-lip breathing. The technique teaches a person to inhale through the nose and exhale through the mouth at a slow, controlled flow. This type of exhalation gives the person a puckered or pursed-lip appearance. By prolonging the expiratory phase of respiration, a small amount of positive end-expiratory pressure (PEEP) is created in the airways that helps to keep them open so that more air can be exhaled. This subsequently reduces air trapping that commonly occurs in conditions such as chronic obstructive pulmonary disease (COPD). Pursed-lip breathing relieves the feeling of shortness of breath, decreases the work of breathing, and improves gas exchange. People also regain a sense of control over their breathing while simultaneously increasing their relaxation.This work is a derivative of StatPearls by Nguyen and Duong and is licensed under CC BY 4.0 Incentive Spirometry An incentive spirometer is a medical device commonly prescribed after surgery to expand the lungs, reduce the buildup of fluid in the lungs, and prevent pneumonia. See Figure 8.6“Incentive Spirometer.png” by BruceBlaus is licensed under CC BY-SA 4.0 for an image of a patient using an incentive spirometer. While sitting upright, if possible, the patient should place the mouthpiece in their mouth and create a tight seal with their lips around it. They should breathe in slowly and as deeply as possible through the tubing with the goal of raising the piston to their prescribed level. The resistance indicator on the right side should be monitored to ensure they are not breathing in too quickly. The patient should attempt to hold their breath for as long as possible (at least 5 seconds) and then exhale and rest for a few seconds. Coughing is expected. Encourage the patient to expel the mucus and not swallow it. This technique should be repeated by the patient 10 times every hour while awake.Cleveland Clinic. (2018, May 2). Incentive spirometer. https://my.clevelandclinic.org/health/articles/4302-incentive-spirometer The nurse may delegate this intervention to unlicensed assistive personnel, but the frequency in which it is completed and the volume achieved should be documented and monitored by the nurse. Coughing and Deep Breathing Coughing and deep breathing is a breathing technique similar to incentive spirometry but no device is required. The patient is encouraged to take deep, slow breaths and then exhale slowly. After each set of breaths, the patient should cough. This technique is repeated 3 to 5 times every hour. Huffing Technique The huffing technique is helpful to teach patients who have difficulty coughing. Teach the patient to inhale with a medium-sized breath and then make a sound like “ha” to push the air out quickly with the mouth slightly open. Vibratory PEP Therapy Vibratory Positive Expiratory Pressure (PEP) Therapy uses handheld devices such as flutter valves or Acapella devices for patients who need assistance in clearing mucus from their airways. These devices require a prescription and are used in collaboration with a respiratory therapist or advanced health care provider. To use vibratory PEP therapy, the patient should sit up, take a deep breath, and blow into the device. A flutter valve within the device creates vibrations that help break up the mucus so the patient can cough and spit it out. Additionally, a small amount of positive end-expiratory pressure (PEEP) is created in the airways that helps to keep them open so that more air can be exhaled. See the supplementary video below regarding how to use the flutter valve device. View this video on Using a Flutter Valve Device (Acapella).NHS University Hospitals Plymouth Physiotherapy. (2015, May 12). Acapella. [Video]. YouTube. All rights reserved. https://youtu.be/XOvonQVCE6Y 8.3 Applying the Nursing Process Open Resources for Nursing (Open RN) Now that we have discussed various concepts related to oxygenation and hypoxia, we will explain how a nurse uses the nursing process to care for patients with alterations in oxygenation. Assessment When assessing a patient’s oxygenation status, there are several subjective and objective assessments to include. Subjective Assessment The primary symptom to assess when a patient is experiencing decreased oxygenation is their level of dyspnea, the medical term for the subjective feeling of shortness of breath or difficulty breathing. Patients can be asked to rate their dyspnea on a scale of 0-10, similar to using a pain rating scale.Registered Nurses’ Association of Ontario. (2005). Nursing care of dyspnea: The 6th vital sign in individuals with chronic obstructive pulmonary disease. https://rnao.ca/bpg/guidelines/dyspnea The feeling of dyspnea can be very disabling for patients. There are many interventions that a nurse can implement to help improve the feeling of dyspnea and, thus, improve a patient’s overall quality of life. It is also important to ask patients if they are experiencing a cough. If a cough is present, determine if sputum is present, and if so, the color and amount of sputum. Sputum is mucus and other secretions that are coughed up from the mouth. The body always produces mucus to keep the delicate tissues of the respiratory tract moist so small particles of foreign matter can be trapped and forced out, but when there is an infection in the lungs, an excess of mucus is produced. The body attempts to get rid of this excess by coughing it up as sputum. The color of a patient’s sputum can provide cues for underlying medical conditions. For example, sputum caused by a respiratory infection is often yellow or green and often referred to as purulent sputum.Barrel, A. (2017, August 13). What is a sputum culture test? MedicalNewsToday. https://www.medicalnewstoday.com/articles/318924#what-is-a-sputum-culture-test See Figure 8.7“Sputnum.JPG” by Zhangmoon618 is licensed under CC0 for an image of purulent sputum. Patients should be asked if they are experiencing chest pain. Chest pain can occur with several types of respiratory and cardiac conditions, some which are emergent. If the patient reports chest pain, first determine if it is an emergency by asking questions such as: - “Does it feel like something is sitting on your chest?” - “Is the pain radiating into your jaw or arm?” - “Do you feel short of breath, dizzy, or nauseated?” If any of these symptoms are occurring, seek emergency medical assistance according to agency policy. If it is not a medical emergency, perform a focused assessment on the chest pain, including onset, location, duration, characteristics, alleviating or aggravating factors, radiation, and if any treatment has been used for the pain.A.D.A.M. Medical Encyclopedia [Internet]. Atlanta (GA): A.D.A.M., Inc.; c1997-2020. Chest Pain; [updated 2020, August 4]. https://medlineplus.gov/ency/article/003079.htm Objective Assessment Focused objective assessments for a patient experiencing decreased oxygenation include assessing airway, evaluating respiratory rate and heart rate, analyzing pulse oximetry readings, and auscultating lung sounds for adventitious sounds. Signs of cyanosis or clubbing should be noted. Clubbing is the enlargement of the fingertips that occurs with chronic hypoxia such as in chronic obstructive pulmonary disease (COPD) or congenital deficits in pediatric patients. See Figure 8.8“Acopaquia.jpg” by Desherinka is licensed under CC BY-SA 4.0 for an image of clubbing. Another sign of chronic hypoxia that often occurs in patients with chronic obstructive pulmonary disease (COPD) includes an increased anterior-posterior chest diameter, often referred to as a barrel chest. A barrel chest results from air trapping in the alveoli. See Figure 8.9“Normal A-P Chest Image.jpg” and “Barrel Chest.jpg” by Meredith Pomietlo for Chippewa Valley Technical College are licensed under CC BY 4.0 for an image of a barrel chest. Diagnostic Tests and Lab Work Diagnostic tests and lab work are based on the patient’s medical condition that is causing the decreased oxygenation. For example, patients with a productive cough may have a chest X-ray or sputum culture ordered, and patients experiencing respiratory distress often have arterial blood gas (ABG) tests performed. A chest X-ray is a fast and painless imaging test that uses certain electromagnetic waves to create pictures of the structures in and around the chest. This test can help diagnose and monitor conditions such as pneumonia, heart failure, lung cancer, and tuberculosis. Health care providers also use chest X-rays to see how well certain treatments are working and to check for complications after certain procedures or surgeries. Chest X-rays are contraindicated during pregnancy.National Heart, Lung, and Blood Institute. (n.d.) Chest x-ray. https://www.nhlbi.nih.gov/health-topics/chest-x-ray,A.D.A.M. Medical Encyclopedia [Internet]. Atlanta (GA): A.D.A.M., Inc.; c1997-2020. Chest x-ray; [updated 2020, August 4]. https://medlineplus.gov/ency/article/003804.htm See Figure 8.10“Chest Xray PA 3-8-2010.png” by Stillwaterising is licensed under CC0 for an image of a chest X-ray. A sputum culture is a diagnostic test that evaluates the type and number of bacteria present in sputum. The patient is asked to cough deeply and spit any mucus that comes up into a sterile specimen container. The sample is sent to a lab where it is placed in a special dish and is watched for two to three days or longer to see if bacteria or other disease-causing germs grow.A.D.A.M. Medical Encyclopedia [Internet]. Atlanta (GA): A.D.A.M., Inc.; c1997-2020. Routine sputum culture; [updated 2020, Aug 4]. https://medlineplus.gov/ency/article/003723.htm See Figure 8.11“m241-8 Blood agar culture of sputum from patient with pneumonia. Comprimised host. Colonies of Candida albicans and pseudomonas aeruginosa (LeBeau)” by Microbe World is licensed under CC BY-NC-SA 2.0 for an image of a sputum culture. For patients experiencing respiratory distress, arterial blood gas (ABG) tests are often ordered. Additional details about ABG tests are discussed in the “Oxygenation Basic Concepts” section of this chapter, as well as in the “Acid-Base Balance” section of the “Fluid and Electrolytes” chapter. See Table 8.3a for a summary of normal ranges of ABG values in adults. Table 8.3a Normal Ranges of ABG Values in Adults \| Value \| Description \| Normal Range \| \|---\|---\|---\| \| pH \| Acid-base balance of blood \| 7.35-7.45 \| \| PaO2 \| Partial pressure of oxygen \| 80-100 mmHg \| \| PaCO2 \| Partial pressure of carbon dioxide \| 35-45 mmHg \| \| HCO3 \| Bicarbonate level \| 22-26 mEq/L \| \| SaO2 \| Calculated oxygen saturation \| 95-100% \| Diagnoses Commonly used NANDA-I nursing diagnoses for patients experiencing decreased oxygenation and dyspnea include Impaired Gas Exchange, Ineffective Breathing Pattern, Ineffective Airway Clearance, Decreased Cardiac Output, and Activity Intolerance. See Table 8.3b for definitions and selected defining characteristics for these commonly used nursing diagnoses.Herdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York, p. 230. Use a current, evidence-based nursing care plan resource when creating a care plan for a patient. Table 8.3b NANDA-I Nursing Diagnoses Related to Decreased Oxygenation and Dyspnea \| NANDA-I Nursing Diagnoses \| Definition \| Selected Defining Characteristics \| \|---\|---\|---\| \| Impaired Gas Exchange \| Excess or deficit in oxygenation and/or carbon dioxide elimination at the alveolar-capillary membrane. \| \| \| Ineffective Breathing Pattern \| Inspiration and/or expiration that does not provide adequate ventilation. \| \| \| Ineffective Airway Clearance \| Inability to clear secretions or obstructions from the respiratory tract to maintain a clear airway. \| \| \| Decreased Cardiac Output \| Inadequate blood pumped by the heart to meet the metabolic demands of the body. \| \| \| Activity Intolerance \| Activity Intolerance: Insufficient physiological or psychological energy to endure or complete required or desired daily activities. \| \| For example, nurses commonly care for patients with chronic obstructive pulmonary disease (COPD). To select an accurate nursing diagnosis for a specific patient with COPD, the nurse compares findings obtained on patient assessment with the defining characteristics of various nursing diagnosis. The nurse selects Ineffective Breathing Pattern after validating this patient is demonstrating the associated signs and symptoms related to this nursing diagnosis: - - Dyspnea - Increase in anterior-posterior chest diameter (e.g., barrel chest) - Nasal flaring - Orthopnea - Prolonged expiration phase - Pursed-lip breathing - Tachypnea - Use of accessory muscles to breathe - Use of three-point position Outcome Identification A broad goal(s) for patients experiencing alterations in oxygenation is: - The patient will have adequate movement of air into and out of the lungs.Johnson, M., Moorhead, S., Bulechek, G., Butcher, H., Maas, M., & Swanson, E. (2012). NOC and NIC linkages to NANDA-I and clinical conditions: Supporting critical reasoning and quality care. Elsevier, pp. 54-55. A sample “SMART” outcome criteria for a patient experiencing dyspnea is: - The patient’s reported level of dyspnea will be within their stated desired range of 1-2 throughout their hospital stay. Planning Interventions According to NOC and NIC Linkages to NANDA-I and Clinical ConditionsJohnson, M., Moorhead, S., Bulechek, G., Butcher, H., Maas, M., & Swanson, E. (2012). NOC and NIC linkages to NANDA-I and clinical conditions: Supporting critical reasoning and quality care. Elsevier, pp. 54-55 and Nursing Interventions Classification (NIC),Butcher, H., Bulechek, G., Dochterman, J., & Wagner, C. (2018). Nursing interventions classification (NIC). Elsevier, pp. 71 and 321 Anxiety Reduction and Respiratory Monitoring are common categories of independent nursing interventions used to care for patients experiencing dyspnea and alterations in oxygenation. Anxiety Reduction is defined as, “Minimizing apprehension, dread, foreboding, or uneasiness related to an unidentified source of anticipated danger.”Johnson, M., Moorhead, S., Bulechek, G., Butcher, H., Maas, M., & Swanson, E. (2012). NOC and NIC linkages to NANDA-I and clinical conditions: Supporting critical reasoning and quality care. Elsevier, pp. 54-55 Respiratory Monitoring is defined as, “Collection and analysis of patient data to ensure airway patency and adequate gas exchange.”Butcher, H., Bulechek, G., Dochterman, J., & Wagner, C. (2018). Nursing interventions classification (NIC). Elsevier, pp. 71 and 321 Selected nursing interventions related to anxiety reduction and respiratory monitoring are listed in the following box. Selected Nursing Interventions to Reduce Anxiety and Perform Respiratory Monitoring Anxiety Reduction - Use a calm, reassuring approach - Explain all procedures, including sensations likely to be experienced during the procedure - Provide factual information concerning diagnosis, treatment, and prognosis - Stay with the patient to promote safety and reduce fear - Encourage the family to stay with the patient, as appropriate - Listen attentively - Create an atmosphere of trust - Encourage verbalization of feelings, perceptions, and fears - Identify when level of anxiety changes - Provide diversional activities geared toward the reduction of tension - Instruct the patient on the use of relaxation techniques - Administer medications to reduce anxiety, as appropriate Respiratory Monitoring - Monitor rate, rhythm, depth, and effort of respirations - Note chest movement, watching for symmetry and use of accessory muscles - Monitor for noisy respirations such as snoring - Monitor breathing patterns - Monitor oxygen saturation levels in sedated patients - Provide for noninvasive continuous oxygen sensors with appropriate alarm systems in patients with risk factors per agency policy and as indicated - Auscultate lung sounds, noting areas of decreased or absent ventilation and presence of adventitious sounds - Monitor patient’s ability to cough effectively - Note onset, characteristics, and duration of cough - Monitor the patient’s respiratory secretions - Provide frequent intermittent monitoring of respiratory status in at-risk patients - Monitor for dyspnea and events that improve and worsen it - Monitor chest X-ray reports as appropriate - Note changes in ABG values as appropriate - Institute resuscitation efforts as needed - Institute respiratory therapy treatments as needed In addition to the independent nursing interventions listed in the preceding box, several nursing interventions can be implemented to manage hypoxia, such as teaching enhanced breathing and coughing techniques, repositioning, managing oxygen therapy, administering medications, and providing suctioning. Refer to Table 8.2b in the “Oxygenation Basic Concepts” section earlier in this chapter for information about these interventions. For additional details regarding managing oxygen therapy, see the “Oxygen Therapy” chapter in Open RN Nursing Skills. Read more information about respiratory medications in the “Respiratory” chapter in Open RN Nursing Pharmacology. Patients should also receive individualized health promotion patient education to enhance their respiratory status. Health promotion education includes encouraging activities such as the following: - Receiving an annual influenza vaccine - Receiving a pneumococcal vaccine every five years as indicated - Stopping smoking - Drinking adequate fluids to thin respiratory secretions - Participating in physical activity as tolerated Implementing Interventions When implementing interventions that have been planned to enhance oxygenation, it is always important to assess the patient’s current level of dyspnea and modify interventions based on the patient’s current status. For example, if dyspnea has worsened, some interventions may no longer be appropriate (such as ambulating), and additional interventions may be needed (such as consulting with a respiratory therapist or administering additional medication). Evaluation After implementing interventions, the effectiveness of interventions should be documented and the overall nursing care plan evaluated. Focused reassessments for evaluating improvement of oxygenation status include analyzing the patient’s heart rate, respiratory rate, pulse oximetry reading, and lung sounds, in addition to asking the patient to rate their level of dyspnea. 8.4 Putting It All Together Open Resources for Nursing (Open RN) The following patient care scenario applies information from this chapter to create an abbreviated nursing care plan and sample documentation note. Patient Scenario Mr. Smith is an 82-year-old patient in a long-term care facility and has a history of chronic obstructive pulmonary disease (COPD). This morning Mr. Smith told the CNA as he was getting ready for breakfast, “I’m feeling short of breath and tired today.” The CNA obtained vital signs and reported them to you: respiratory rate 24, O2 sat 86%, pulse 88, and temperature 36.8 C. Applying the Nursing Process Assessment: You auscultate Mr. Smith’s breath sounds and find scattered wheezing and rhonchi anteriorly, with diminished breath sounds in the posterior lower lobes. You ask Mr. Smith to rate his shortness of breath now on a scale from 0-10 and he reports it is a “4,” but usually a “2” during activity. While assessing Mr. Smith, you note he is using accessory muscles to breathe and is sitting up in the tripod position. He also has a barrel chest. You quickly check his chart and note the following orders and scheduled medications: - Tiotropium (Spiriva) inhaler daily - Fluticasone (Flovent) inhalers daily - Oxygen via nasal cannula at 1-2 L per minute as needed to maintain O2 saturation greater than 90% - Albuterol nebulizer as needed for wheezing Based on this information, you formulate the following nursing care plan: Nursing Diagnosis: Ineffective Breathing Pattern related to respiratory muscle fatigue as manifested by tachypnea and use of accessory muscles to breathe and patient stating, “I’m feeling short of breath and tired today.” Overall Goal: The patient will have adequate movement of air into and out of the lungs. SMART Expected Outcome: Mr. Smith’s reported level of dyspnea will be within his stated desired range of 1-2 by the end of the shift. Planned Nursing Interventions with Rationale: \| Interventions \| Rationale \| \|---\|---\| \| 1. Implement NIC interventions for Respiratory Monitoring NIC (as outlined in Box 8.3 ). \| Establish a baseline status for today and continue to monitor for improvement or worsening as interventions are implemented. \| \| 2. Implement NIC Interventions for Anxiety Reduction (as outlined in Box 8.3). \| Dyspnea creates feelings of anxiety. Decreasing the patient’s anxiety levels will help decrease the feeling of dyspnea. \| \| 3. Place patient in high Fowler’s or tripod position as needed to reduce feelings of dyspnea. \| Positioning will assist in maximum expansion of lungs. \| \| 4. Apply oxygen via nasal cannula, starting at 1 L/min and titrate until 90% pulse oximetry reading is obtained per standing order. \| Oxygen therapy will reduce the work of breathing. \| 5. Administer scheduled and PRN medications: \| Each medication has a different mechanism of action that will assist Mr. Smith’s dyspnea. \| \| 6. Encourage Mr. Smith to use pursed-lip breathing and Huff coughing. \| Pursed-lip breathing will help keep the airways open longer on expiration so that more air can then be inhaled on inspiration. Huff coughing will help clear secretions. \| \| 7. Encourage fluids (2000 mL/24 hours) and monitor intake and output. \| Additional fluids will help thin secretions so they can more easily be coughed up. Mr. Smith does not have fluid restrictions, but it is important to monitor intake/output when encouraging fluids, especially in elderly patients who have increased risk for developing fluid overload. \| \| 8. Schedule care activities to allow frequent rest periods. \| Resting frequently decreases oxygen demand. \| \| 9. Encourage ambulation as tolerated, with the CNA, in the hallway, after the O2 saturation is greater than 90%. \| Ambulation will help to mobilize the secretions so they can be removed. \| Evaluation: After administering medications and applying the oxygen, you reassess Mr. Smith and find the following: respiratory rate 16, pulse 78, and O2 sat 90% with NC at 1 L/min. The wheezing and rhonchi in the anterior lungs have diminished. You ask Mr. Smith how he is feeling. He rates his current level of dyspnea as a “2” and states, “I feel less short of breath but I am still tired.” The SMART outcome was “met.” You encourage Mr. Smith to rest after eating breakfast, but encourage a walk in the hallway later that morning. You enter the following documentation note in the patient record. Sample Documentation Note Upon awakening, the patient reported a dyspnea level of a “4” and stated, “I’m feeling short of breath and tired today.” Vital signs were respiratory rate 24, O2 sat 86%, pulse 88, and temperature 36.8 C. Scattered wheezing and rhonchi present anteriorly, with diminished breath sounds in the posterior lower lobes. Oxygen applied via nasal cannula at 1 L/min; albuterol nebulizer and scheduled medications were administered. Patient was placed in tripod position at edge of bed and encouraged to use pursed-lip breathing and Huff coughing. Post albuterol administration, vital signs were respiratory rate 16, pulse 78, and O2 sat 90% on room air. The wheezing and rhonchi in the anterior lungs were diminished. Patient reported dyspnea decreased to a “2” but stated, “I feel less short of breath but I am still tired.” Encouraged patient to push fluids and ambulate as tolerated today, along with frequent rest breaks. Will continue to monitor respiratory rate, pulse, lung sounds, and reported level of dyspnea every four hours today. 8.5 Learning Activities Open Resources for Nursing (Open RN) Learning Activities (Answers to “Learning Activities” can be found in the “Answer Key” at the end of the book. Answers to interactive activity elements will be provided within the element as immediate feedback.) - You are providing care for Mrs. Jones, an 83-year-old female patient admitted to the medical surgical floor with worsening pneumonia. Upon auscultation of the patient’s lung fields, you note scattered crackles and diminished breath sounds throughout all lung fields. Mrs. Jones requires 4L O2 via nasal cannula to maintain an oxygen saturation of 94%. You have constructed a nursing care diagnosis of Ineffective Breathing Pattern. What nursing interventions might you consider to help improve the patient’s breathing pattern? An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=292#h5p-66 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=292#h5p-20 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=292#h5p-99 “Gas Exchange Case Study” by Susan Jepsen for Lansing Community College are licensed under CC BY 4.0 VIII Glossary Open Resources for Nursing (Open RN) Apnea: Temporary cessation of breathing. When apnea occurs during sleep, it is often caused by the condition called Obstructive Sleep Apnea (OSA). Arterial Blood Gas (ABG): Diagnostic test performed on an arterial sample of blood to determine its pH level, oxygenation status, and carbon dioxide status. Barrel chest: An increased anterior-posterior chest diameter, resulting from air trapping in the alveoli, that occurs in chronic respiratory disease. Bilevel Positive Airway Pressure (BiPAP): A BiPAP is an oxygenation device similar to a CPAP device in its use to prevent airways from collapsing, but it has two pressure settings. One setting occurs during inhalation and a lower pressure setting is used during exhalation. BiPAP devices may be used in the home to treat obstructive sleep apnea or in hospitals to treat patients in acute respiratory distress. For more information, see the “Oxygenation Equipment” section of the “Oxygen Therapy” chapter in Open RN Nursing Skills. Bradypnea: Decreased respiratory rate less than the normal range according to the patient’s age. Cardiac output: The amount of blood the heart pumps in one minute. Continuous Positive Airway Pressure (CPAP): A CPAP is an oxygenation device is typically used for patients who are able to breath spontaneously but need assistance in keeping their airway unobstructed, such as those with obstructive sleep apnea. The CPAP device consists of a mask that covers the patient’s nose, or nose and mouth, and is attached to a machine that continuously applies mild air pressure to keep the airways from collapsing. For more information, see the “Oxygenation Equipment” section of the “Oxygen Therapy” chapter in Open RN Nursing Skills. Clubbing: Enlargement of the fingertips that occurs with chronic hypoxia. Coughing and deep breathing: A breathing technique where the patient is encouraged to take deep, slow breaths and then exhale slowly. After each set of breaths, the patient should cough. This technique is repeated 3 to 5 times every hour. Cyanosis: Bluish discoloration of the skin and mucous membranes. Dyspnea: A subjective feeling of not getting enough air. Depending on severity, dyspnea causes increased levels of anxiety. Endotracheal Tube (ET tube): An ET tube is inserted by an advanced practitioner to maintain a secure airway when a patient is experiencing respiratory failure or is receiving general anesthesia. For more information, see the “Oxygenation Equipment” section of the “Oxygen Therapy” chapter in Open RN Nursing Skills. HCO3: Bicarbonate level of arterial blood indicated in an arterial blood gas (ABG) result. Normal range is 22-26. Huffing technique: A technique helpful for patients who have difficulty coughing. Teach the patient to inhale with a medium-sized breath and then make a sound like “ha” to push the air out quickly with the mouth slightly open. Hypercapnia: Elevated level of carbon dioxide in the blood. Hypoxemia: A specific type of hypoxia that is defined as decreased partial pressure of oxygen in the blood (PaO2) indicated in an arterial blood gas (ABG) result. Hypoxia: A reduced level of tissue oxygenation. Hypoxia has many causes, ranging from respiratory and cardiac conditions to anemia. Incentive spirometer: A medical device commonly prescribed after surgery to reduce the buildup of fluid in the lungs and to prevent pneumonia. While sitting upright, the patient should breathe in slowly and deeply through the tubing with the goal of raising the piston to a specified level. The patient should attempt to hold their breath for 5 seconds, or as long as tolerated, and then rest for a few seconds. This technique should be repeated by the patient 10 times every hour while awake. Mechanical ventilator: A mechanical ventilator is a machine attached to an endotracheal tube to assist or replace spontaneous breathing. For more information, see the “Oxygenation Equipment” section of the “Oxygen Therapy” chapter in Open RN Nursing Skills. Orthopnea: Difficulty in breathing that occurs when lying down and is relieved upon changing to an upright position. PaCO2: Partial pressure of carbon dioxide level in arterial blood indicated in an ABG result. Normal range is 35-45 mmHg. PaO2: Partial pressure of oxygen level in arterial blood indicated in an ABG result. Normal range is 80-100 mmHg. Perfusion: The passage of blood through the arteries to an organ or tissue. Pursed-lip breathing: A breathing technique that encourages a person to inhale through the nose and exhale through the mouth at a slow, controlled flow. Purulent sputum: Yellow or green sputum that often indicates a respiratory infection. Respiration: Gas exchange occurs at the alveolar level where blood is oxygenated and carbon dioxide is removed. SaO2: Calculated oxygen saturation level in an ABG result. Normal range is 95-100%. SpO2: Hemoglobin saturation level measured by pulse oximetry. Normal range is 94-98%. Sputum: Mucus and other secretions that are coughed up from the mouth. Tachypnea: Elevated respiratory rate above normal range according to the patient’s age. Tripod position: A position that enhances air exchange when a patient sits up and leans over by resting their arms on their legs or on a bedside table; also referred to as a three-point position. Ventilation: Mechanical movement of air into and out of the lungs. Vibratory Positive Expiratory Pressure (PEP) Therapy: Handheld devices such as flutter valves or Acapella devices used with patients who need assistance in clearing mucus from their airways. Infection IX 9.1 Infection Introduction Open Resources for Nursing (Open RN) Learning Objectives - Outline the factors that put patients at risk for infection - Identify factors related to infection across the life span - Outline personal practices that reduce the risk of infection transmission - Base your care decision on the signs and symptoms of infection - Base your response on an interpretation of the diagnostic tests related to patient’s infectious process - Detail the nursing interventions to support or minimize the physical and psychological effects of the infectious process - Demonstrate the ability to correlate nursing interventions to methods used to prevent or disrupt the chain of infection - Follow industry standards for transmission-based precautions - Identify evidence-based practices Have you ever wondered how nurses can be exposed to patients with communicable diseases day after day and not become ill? There are many factors that affect the body’s ability to defend against infection and place some individuals at greater risk of developing an infection. When an infection does occur, early recognition is important to prevent it from spreading within the individual, as well as to others. Protecting people from developing an infection, as well as preventing the spread of infection, is a major concern for nurses. This chapter will discuss the physiology of the inflammation and infectious processes and nursing interventions to prevent the spread of infection. 9.2 Basic Concepts Open Resources for Nursing (Open RN) Normal Flora and Microbiome Microorganisms occur naturally and are present everywhere in our environment. Some microorganisms live on the skin, in the nasopharynx, and in the gastrointestinal tract, but don’t become an infection unless the host becomes susceptible. These microorganisms are called normal flora . Over the past several, it has been discovered that every human being carries their own individual suite of microorganisms in and on their body referred to as their microbiome. A person’s microbiome is acquired at birth and evolves over their lifetime. It is different across body sites and between individuals. A person’s gut microbiome has recently been found to impact their immune system.Davis, C. P. Normal flora. (1996). In S. Baron (Ed.), Medical Microbiology (4th ed.). University of Texas Medical Branch at Galveston. https://www.ncbi.nlm.nih.gov/books/NBK7617/,This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction Pathogens Microorganisms that cause disease are called pathogens. There are four common types of pathogens, including viruses, bacteria, fungi, and parasites. After a host (i.e., the person) becomes infected by a virus, the virus invades the body’s cells and uses the components of the cell to replicate and produce more viruses. After the virus replication cycle is complete, the new viruses are released into the body, causing damage or destruction of the host’s cells.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction Antiviral medications can be used to treat some viral infections. Antibiotics do not kill viruses and are ineffective as a treatment for viral infections. See Figure 9.1“3D_medical_animation_corona_virus.jpg” by https://www.scientificanimations.com is licensed under CC BY-SA 4.0 for an image of a virus. Bacteria Bacteria are microorganisms made of a single cell. They are very diverse, have a variety of shapes and features, and have the ability to live in any environment, including your body. However, not all bacteria cause infections. Those that cause infection are called pathogenic bacteria. See Figure 9.2“E._coli_Bacteria_(16578744517).jpg” by NIAID is licensed under CC BY 2.0 for an image of a bacterium called Escherichia coli (E. coli). A patient is susceptible to bacterial infections when their immune system is compromised by chronic diseases or certain types of medications. Antibiotics are used to treat bacterial infections. However, some strains of bacteria have become resistant to antibiotics, making them difficult to treat. For example, infections caused by methicillin-resistant Staphylococcus Aureus (MRSA) are resistant to many types of antibiotics and have the capability of producing severe and life-threatening infections. MRSA infections usually require IV antibiotics and may require treatment for long periods of time.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction Fungi There are millions of different fungal species on Earth. Fungi can be found everywhere in the environment, including indoors, outdoors, and on human skin, but only about 300 species cause infection when they overgrow. Candida albicans is a type of fungus that can cause oral thrush and vaginal yeast infections, especially in susceptible patients or those taking antibiotics.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction See Figure 9.3“Human_tongue_infected_with_oral_candidiasis.jpg” by James Heilman, MD is licensed under CC BY-SA 3.0 for an image of oral thrush. This structure can make them harder to kill. Some new strains of fungal infections are proving to be especially dangerous, such as Candida auris, which is difficult to diagnose and treat, and can cause outbreaks in health care facilities.Manoylov, M. K. (2020, November 6). What are cytokines? Live Science. https://www.livescience.com/what-are-cytokines.html Parasites Parasites are organisms that behave like tiny animals, living in or on a host, and feeding at the expense of the host. Three main types of parasites can cause disease in humans. These include the following: - Protozoa: Single-celled organisms that can live and multiply in your body - Helminths: Multi-celled organisms that can live inside or outside your body and are commonly known as worms - Ectoparasites: Multi-celled organisms that live on or feed off skin, including ticks and mosquitos Parasites can be spread several ways, including through contaminated soil, water, food, and blood, as well as through sexual contact and insect bites.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction See Figure 9.4“Piece_of_intestine,_blocked_by_worms_(16424898321).jpg” by SuSanA Secretariat is licensed under CC BY 2.0 for an image of a helminth infection causing intestinal obstruction in a child. 9.3 Natural Defenses Against Infection Open Resources for Nursing (Open RN) There are two basic ways the body defends against pathogens: nonspecific innate immunity and specific adaptive immunity. Nonspecific Innate Immunity Nonspecific innate immunity is a system of defenses in the body that targets invading pathogens in a nonspecific manner. It is called “innate” because it is present from the moment we are born. Nonspecific innate immunity includes physical defenses, chemical defenses, and cellular defenses.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction Physical Defenses Physical defenses are the body’s most basic form of defense against infection. They include physical barriers to microbes, such as skin and mucous membranes, as well as mechanical defenses that physically remove microbes and debris from areas of the body where they might cause harm or infection. In addition, a person’s microbiome provides physical protection against disease as normal flora compete with pathogens for nutrients and cellular-binding sites.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction Skin One of the body’s most important physical barriers is the skin barrier, which is composed of three layers of closely packed cells. See Figure 9.5“OSC_Microbio_17_02_Skin.jpg” by OpenStax is licensed under CC BY 4.0. Access for free at<EMAIL_ADDRESS>for an illustration of the layers of skin. The topmost layer of skin called the epidermis consists of cells that are packed with keratin. Keratin makes the skin’s surface mechanically tough and resistant to degradation by bacteria. Infections can occur when the skin barrier is broken, allowing the entry of opportunistic pathogens that infect the skin tissue surrounding the wound and possibly spread to deeper tissues.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction Mucus Membranes The mucous membranes lining the nose, mouth, lungs, and urinary and digestive tracts provide another nonspecific barrier against potential pathogens. Mucous membranes consist of a layer of epithelial cells bound by tight junctions. The epithelial cells secrete a moist, sticky substance called mucous. Mucous covers and protects the fragile cell layers beneath it and also traps debris, including microbes. Mucus secretions also contain antimicrobial peptides.The Integrative HMP (iHMP) Research Network Consortium. (2019). Proctor, L. M., Creasy, H. H., et. al. The integrative human microbiome project. Nature, 569, 641–648. https://doi.org/10.1038/s41586-019-1238-8 In many regions of the body, mechanical actions flush mucus (along with trapped or dead microbes) out of the body or away from potential sites of infection. For example, in the respiratory system, inhalation can bring microbes, dust, mold spores, and other small airborne debris into the body. This debris becomes trapped in the mucus lining the respiratory tract. The epithelial cells lining the upper parts of the respiratory tract have hair-like appendages known as cilia. Movement of the cilia propels debris-laden mucus out and away from the lungs. The expelled mucus is then swallowed and destroyed in the stomach, coughed up, or sneezed out. This system of removal is often called the mucociliary escalator. Disruption of the mucociliary escalator by the damaging effects of smoking can lead to increased colonization of bacteria in the lower respiratory tract and frequent infections, which highlights the importance of this physical barrier to host defenses.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction See Figure 9.6“Bronchiolar_epithelium_3_-_SEM.jpg” by Charles Daghlian is licensed by CC0 for an image of a magnified mucociliary escalator. Like the respiratory tract, the digestive tract is a portal of entry through which microbes enter the body, and the mucous membranes lining the digestive tract provide a nonspecific physical barrier against ingested microbes. The intestinal tract is lined with epithelial cells, interspersed with mucus-secreting goblet cells. This mucus mixes with material received from the stomach, trapping foodborne microbes and debris, and the mechanical action of peristalsis (a series of muscular contractions in the digestive tract) moves this mixture through the intestines and excretes it in feces.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction For this reason, feces can contain microorganisms that can cause the spread of infection; therefore, good hand hygiene is vital. Endothelia The epithelial cells lining the urogenital tract, blood vessels, lymphatic vessels, and other tissues are known as endothelia. These tightly packed cells provide an effective frontline barrier against invaders. The endothelia of the blood-brain barrier, for example, protects the central nervous system (CNS) from microorganisms. Infection of the CNS can quickly lead to serious and often fatal inflammation. The protection of the blood-brain barrier keeps the cerebrospinal fluid that surrounds the brain and spinal cord sterile.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction See Figure 9.7“Protective_barriers_of_the_brain.jpg” by Stolp H. B., Liddelow S. A., Sá-Pereira I., Dziegielewska K. M., & Saunders N. R. is licensed under CC BY-SA 3.0 for an illustration of the blood-brain barrier. Mechanical Defenses In addition to physical barriers that keep microbes out, the body has several mechanical defenses that physically remove pathogens from the body and prevent them from taking up residence. For example, the flushing action of urine and tears serves to carry microbes away from the body. The flushing action of urine is responsible for the normally sterile environment of the urinary tract. The eyes have additional physical barriers and mechanical mechanisms for preventing infections. The eyelashes and eyelids prevent dust and airborne microorganisms from reaching the surface of the eye. Any microbes or debris that make it past these physical barriers are flushed out by the mechanical action of blinking, which bathes the eye in tears, washing debris away.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction See Figure 9.8“Eyelashes_of_a_2-month-old_baby_boy.png” by Karthik.yerramilly is licensed under CC BY-SA 4.0 for an image of an infant’s eyelashes that prevent dust from reaching the surface of the eye. Microbiome Normal flora that contribute to an individual’s microbiome serve as an important first-line defense against invading pathogens. Through their occupation of cellular binding sites and competition for available nutrients, normal flora prevent the early steps of pathogen attachment and proliferation required for the establishment of an infection. For example, in the vagina, normal flora compete with opportunistic pathogens like Candida albicans. This competition prevents yeast infection by limiting the availability of nutrients and inhibiting the growth of Candida, keeping its population in check. Similar competitions occur between normal flora and potential pathogens on the skin, in the upper respiratory tract, and in the gastrointestinal tract.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction The importance of the normal flora in host defenses is highlighted by a person’s increased susceptibility to infectious diseases when their microbiome is disrupted or eliminated. For example, treatment with antibiotics can significantly deplete the normal flora of the gastrointestinal tract, providing an advantage for pathogenic bacteria such as Clostridium difficile (C-diff) to colonize and cause diarrheal infection. Diarrhea caused by C-diff can be severe and potentially lethal. In fact, a recent strategy for treating recurrent C-diff infections is fecal transplantation that involves the transfer of fecal material from a donor into the intestines of the patient as a method of restoring their normal flora.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction Chemical Defenses In addition to physical defenses, our nonspecific innate immune system uses several chemical mediators that inhibit microbial invaders. The term chemical mediators encompasses a wide array of substances found in various fluids and tissues throughout the body. For example, sebaceous glands in the dermis secrete an oil called sebum that is released onto the skin surface through hair follicles. Sebum provides an additional layer of defense by helping seal off the pore of the hair follicle and preventing bacteria on the skin’s surface from invading sweat glands and surrounding tissue. Environmental factors can affect these chemical defenses of the skin. For example, low humidity in the winter makes the skin more dry and susceptible to pathogens normally inhibited by the skin’s low pH. Application of skin moisturizer restores moisture and essential oils to the skin and helps prevent dry skin from becoming infected.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction Examples of other chemical defenses are enzymes, pH level, and chemical mediators. Enzymes in saliva and the digestive tract eliminate most pathogens that manage to survive the acidic environment of the stomach. In the urinary tract, the slight acidity of urine inhibits the growth of potential pathogens in the urinary tract. The respiratory tract also uses various chemical mediators in the nasal passages, trachea, and lungs that have antibacterial properties.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction Plasma Protein Mediators In addition to physical, mechanical, and chemical defenses, there are also nonspecific innate immune factors in plasma, the fluid portion of blood, such as acute-phase proteins, complement proteins, and cytokines. These plasma protein mediators contribute to the inflammatory response.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction An example of an acute-phase protein is C-reactive protein. High levels of C-reactive protein indicate a serious infection or other medical condition that causes inflammation is occurring.This work is a derivative of Concepts of Biology – 1st Canadian Edition by Molnar & Gair and is licensed under CC BY 4.0. Complement proteins are always present in the blood and tissue fluids, allowing them to be activated quickly. They aid in the destruction of pathogens by piercing their outer membranes (cell lysis) or by making them more attractive to phagocytic cells such as macrophages.Sproston, N. R., & Ashworth, J. J. (2018). Role of c-reactive protein at sites of inflammation and infection. Frontiers in Immunology, 9, 754. https://doi.org/10.3389/fimmu.2018.00754 Cytokines are proteins that affect interaction and communication between cells. When a pathogen enters the body, the first immune cell to notice the pathogen is like the conductor of an orchestra. That cell directs all the other immune cells by creating and sending out messages (cytokines) to the rest of the organs or cells in the body to respond to and initiate inflammation. Too many cytokines can have a negative effect and result in what’s known as a cytokine storm.Complement. (2018). In Britannica. https://www.britannica.com/science/complement-immune-system-component,Arango Duque, G., & Descoteaux, A. (2014). Macrophage cytokines: Involvement in immunity and infectious diseases. Frontiers in Immunology, 5, 491. https://doi.org/10.3389/fimmu.2014.00491 A cytokine storm is a severe immune reaction in which the body releases too many cytokines into the blood too quickly. A cytokine storm can occur as a result of an infection, autoimmune condition, or other disease. Signs and symptoms include high fever, inflammation, severe fatigue, and nausea. A cytokine storm can be severe or life-threatening and lead to multiple organ failure. For example, many COVID-19 complications and deaths were caused by a cytokine storm.National Cancer Institute (n.d.) NCI Dictionary of Cancer Terms. https://www.cancer.gov/publications/dictionaries/cancer-terms/def/cytokine-storm,Hojyo, S., Uchida, M., Tanaka, K., et al. (2020). How COVID-19 induces cytokine storm with high mortality. Inflammation and Regeneration, 40(37). https://doi.org/10.1186/s41232-020-00146-3 Inflammation Inflammation is a response triggered by a cascade of chemical mediators and occurs when pathogens successfully breach the nonspecific innate immune system or when an injury occurs. Although inflammation is often perceived as a negative consequence of injury or disease, it is a necessary process that recruits cellular defenses needed to eliminate pathogens, remove damaged and dead cells, and initiate repair mechanisms. Excessive inflammation, however, can result in local tissue damage, and in severe cases, such as sepsis, it can become deadly.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction An immediate response to tissue injury is acute inflammation. Vasoconstriction occurs to minimize blood loss if injury has occurred. Vasoconstriction is followed by vasodilation with increased permeability of the blood vessels due to the release of histamine by mast cells. Histamine contributes to the five observable signs of the inflammatory response: erythema (redness), edema (swelling), heat, pain, and altered function. It is also associated with an influx of phagocytes at the site of injury and/or infection. See Figure 9.9“OSC_Microbio_17_06_Erythema.jpg” by OpenStax is licensed under CC BY 4.0. Access for free at<EMAIL_ADDRESS>for an illustration of the inflammatory response, with (a) demonstrating when mast cells detect injury to nearby cells and release histamine, initiating an inflammatory response and (b) illustrating where histamine increases blood flow to the wound site and the associated increased vascular permeability allows fluid, proteins, phagocytes, and other immune cells to enter infected tissue. These events result in the swelling and reddening of the injured site. The increased blood flow to the injured site causes it to feel warm. Inflammation is also associated with pain due to these events stimulating nerve pain receptors in the tissue. Increasing numbers of neutrophils are then recruited to the area to fight pathogens. As the fight rages on, white blood cells are recruited to the area, and pus forms from the accumulation of neutrophils, dead cells, tissue fluids, and lymph. Typically, after a few days, macrophages clear out this pus.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction During injury, if this nonspecific inflammatory process does not successfully kill the pathogens, infection occurs. Fever A fever is part of the inflammatory response that extends beyond the site of infection and affects the entire body, resulting in an overall increase in body temperature. The rise in body temperature also inhibits the growth of many pathogens. During fever, the patient’s skin may appear pale due to vasoconstriction of the blood vessels in the skin to divert blood flow away from extremities, minimize the loss of heat, and raise the body’s core temperature. The hypothalamus also stimulates the shivering of muscles to generate heat and raise the core temperature.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction A low-level fever is thought to help an individual overcome an illness. However, in some instances, this immune response can be too strong, causing tissue and organ damage and, in severe cases, even death. For example, Staphylococcus aureus and Streptococcus pyogenes are capable of producing superantigens that cause toxic shock syndrome and scarlet fever, respectively. Both of these conditions are associated with extremely high fevers in excess of 42 °C (108 °F) that must be managed to prevent tissue injury and death.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction When a fever breaks, the hypothalamus stimulates vasodilation, resulting in a return of blood flow to the skin and a subsequent release of heat from the body. The hypothalamus also stimulates sweating, which cools the skin as the sweat evaporates.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction Specific Adaptive Immunity Now that we have discussed several nonspecific innate defenses against a pathogen, let’s discuss specific adaptive immunity. Specific adaptive immunity is the immune response that is activated when the nonspecific innate immune response is insufficient to control an infection. There are two types of adaptive responses: the cell-mediated immune response, which is carried out by T cells, and the humoral immune response, which is controlled by activated B cells and antibodies.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction B cells mature in the bone marrow. B cells make Y-shaped proteins called antibodies that are specific to each pathogen and lock onto its surface and mark it for destruction by other immune cells. The five classes of antibodies are IgG, IgM, IgA, IgD, and IgE. They also turn into memory B cells.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction T cells mature in the thymus. T cells are categorized into three classes: helper T cells, regulatory T cells, and cytotoxic T cells. Helper T cells stimulate B cells to make antibodies and help killer cells develop. T cells also use cytokines as messenger molecules to send chemical instructions to the rest of the immune system to ramp up its response.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction Specific adaptive immunity also creates memory cells for each specific pathogen that provides the host with long-term protection from reinfection with that pathogen. On reexposure, these memory cells facilitate an efficient and quick immune response. For example, when an individual recovers from chicken pox, the body develops a memory of the varicella-zoster virus that will specifically protect it from reinfection if it is exposed to the virus again.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction See Figure 9.10“2211_Cooperation_Between_Innate_and_Immune_Responses.jpg” by OpenStax is licensed under CC BY 3.0. for an illustration of innate immunity and specific adaptive immunity that occurs in response to a pathogen entering the body through the nose. 9.4 Infection Open Resources for Nursing (Open RN) An infection is the invasion and growth of a microorganism within the body. Infection can lead to disease that causes signs and symptoms resulting in a deviation from the normal structure or functioning of the host. Infection occurs when nonspecific innate immunity and specific adaptive immunity defenses are inadequate to protect an individual against the invasion of a pathogen. The ability of a microorganism to cause disease is called pathogenicity, and the degree to which a microorganism is likely to become a disease is called virulence. Virulence is a continuum. On one end of the spectrum are organisms that are not harmful, but on the other end are organisms that are highly virulent. Highly virulent pathogens will almost always lead to a disease state when introduced to the body, and some may even cause multi-organ and body system failure in healthy individuals. Less virulent pathogens may cause an initial infection, but may not always cause severe illness. Pathogens with low virulence usually result in mild signs and symptoms of disease, such as a low-grade fever, headache, or muscle aches, and some individuals may even be asymptomatic.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction An example of a highly virulent microorganism is Bacillus anthracis, the pathogen responsible for anthrax. The most serious form of anthrax is inhalation anthrax. After B. anthracis spores are inhaled, they germinate. An active infection develops, and the bacteria release potent toxins that cause edema (fluid buildup in tissues), hypoxia (a condition preventing oxygen from reaching tissues), and necrosis (cell death and inflammation). Signs and symptoms of inhalation anthrax include high fever, difficulty breathing, vomiting, coughing up blood, and severe chest pains suggestive of a heart attack. With inhalation anthrax, the toxins and bacteria enter the bloodstream, which can lead to multi-organ failure and death of the patient.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction Primary Pathogens Versus Opportunistic Pathogens Pathogens can be classified as either primary pathogens or opportunistic pathogens. A primary pathogen can cause disease in a host regardless of the host’s microbiome or immune system. An opportunistic pathogen, by contrast, can cause disease only in situations that compromise the host’s defenses, such as the body’s protective barriers, immune system, or normal microbiome. Individuals susceptible to opportunistic infections include the very young, the elderly, women who are pregnant, patients undergoing chemotherapy, people with immunodeficiencies (such as acquired immunodeficiency syndrome [AIDS]), patients who are recovering from surgery, and those who have nonintact skin (such as a severe wound or burn).This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction An example of a primary pathogen is enterohemorrhagic E. coli that produces a toxin that leads to severe and bloody diarrhea, inflammation, and renal failure, even in patients with healthy immune systems. Staphylococcus epidermidis, on the other hand, is an opportunistic pathogen that is a frequent cause of health-care acquired infection.Butcher, H., Bulechek, G., Dochterman, J., & Wagner, C. (2018). Nursing interventions classification (NIC). Elsevier. pp. 214, 226-227, 346. S. epidermidis, often referred to as “staph,” is a member of the normal flora of the skin. However, in hospitals, it can grow in biofilms that form on catheters, implants, or other devices that are inserted into the body during surgical procedures. Once inside the body, it can cause serious infections such as endocarditis.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction Other members of normal flora can cause opportunistic infections. For example, some microorganisms that reside harmlessly in one location of the body can cause disease if they are passed to a different body system. For example, E. coli is normally found in the large intestine, but can cause a urinary tract infection if it enters the bladder.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction Normal flora can also cause disease when a shift in the environment of the body leads to overgrowth of a particular microorganism. For example, the yeast Candida is part of the normal flora of the skin, mouth, intestine, and vagina, but its population is kept in check by other organisms of the microbiome. When an individual takes antibiotics, bacteria that would normally inhibit the growth of Candida can be killed off, leading to a sudden growth in the population of Candida. An overgrowth of Candida can manifest as oral thrush (growth on mouth, throat, and tongue) or a vaginal yeast infection. Other scenarios can also provide opportunities for Candida to cause infection. For example, untreated diabetes can result in a high concentration of glucose in a patient’s saliva that provides an optimal environment for the growth of Candida, resulting in oral thrush. Immunodeficiencies, such as those seen in patients with HIV, AIDS, and cancer, also lead to Candida infections.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction Stages of Pathogenesis To cause disease, a pathogen must successfully achieve four stages of pathogenesis to become an infection: exposure, adhesion (also called colonization), invasion, and infection. The pathogen must be able to gain entry to the host, travel to the location where it can establish an infection, evade or overcome the host’s immune response, and cause damage (i.e., disease) to the host. In many cases, the cycle is completed when the pathogen exits the host and is transmitted to a new host.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction Exposure An encounter with a potential pathogen is known as exposure. The food we eat and the objects we touch are all ways that we can come into contact with potential pathogens. Yet, not all contacts result in infection and disease. For a pathogen to cause disease, it needs to be able to gain access into host tissue. An anatomic site through which pathogens can pass into host tissue is called a portal of entry. Portals of entry are locations where the host cells are in direct contact with the external environment, such as the skin, mucous membranes, respiratory, and digestive systems. Portals of entry are illustrated in Figure 9.11.“OSC_Microbio_15_02_Portal.jpg” by OpenStax is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology@9.8/pages/15-2-how-pathogens-cause-disease.,This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction Adhesion Following initial exposure, the pathogen adheres at the portal of entry. The term adhesion refers to the capability of pathogenic microbes to attach to the cells of the body, also referred to as colonization.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction Invasion After successful adhesion, the invasion proceeds. Invasion means the spread of a pathogen throughout local tissues or the body. Pathogens may also produce virulence factors that protect them against immune system defenses and determine the degree of tissue damage that occurs. Intracellular pathogens like viruses achieve invasion by entering the host’s cells and reproducing.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction Infection Following invasion, successful multiplication of the pathogen leads to infection. Infections can be described as local, secondary, or systemic, depending on the extent of the infection.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction A local infection is confined to a small area of the body, typically near the portal of entry. For example, a hair follicle infected by Staphylococcus aureus infection may result in a boil around the site of infection, but the bacterium is largely contained to this small location. Other examples of local infections that involve more extensive tissue involvement include urinary tract infections confined to the bladder or pneumonia confined to the lungs. Localized infections generally demonstrate signs of inflammation, such as redness, swelling, warmth, pain, and purulent drainage. However, extensive tissue involvement can also cause decreased functioning of the organ affected.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction In a secondary infection a localized pathogen, or the toxins it produces, can spread to a secondary location. For example, a dental hygienist nicking a patient’s gum with a sharp tool can cause a local infection in the gum by Streptococcus bacteria found in the oral normal flora. The Streptococcus bacteria may then gain access to the bloodstream and make their way to other locations within the body such as the heart valves, resulting in a secondary infection.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction When an infection becomes disseminated throughout the body, it is called a systemic infection. For example, infection by the varicella-zoster virus typically gains entry through a mucous membrane of the upper respiratory system. It then spreads throughout the body, resulting in a classic red rash associated with chicken pox. Because these lesions are not sites of initial infection, they are signs of a systemic infection. Systemic infections can cause fever, increased heart and respiratory rates, lethargy, malaise, anorexia, and tenderness and enlargement of the lymph nodes.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction Sometimes a primary infection can lead to a secondary infection by an opportunistic pathogen. For example, when a patient experiences a primary infection from influenza, it can damage and decrease the defense mechanisms of the lungs, making the patient more susceptible to a secondary pneumonia by a bacterial pathogen like Haemophilus influenzae. Additionally, treatment of the primary infection may lead to a secondary infection caused by an opportunistic pathogen. For example, antibiotic therapy targeting the primary infection alters the normal flora and creates an opening for opportunistic pathogens like Clostridium difficile or Candida Albicans to cause a secondary infection.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction Bacteremia, SIRS, Sepsis, and Septic Shock When infection occurs, pathogens can enter the bloodstream. The presence of bacteria in blood is called bacteremia. If bacteria are both present and multiplying in the blood, it is called septicemia.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction Systemic inflammatory response syndrome (SIRS) is an exaggerated inflammatory response that affects the entire body. It is the body’s reaction to a noxious stressor, including causes such as infection and acute inflammation, but other conditions can trigger it as well. Signs of SIRS are as follows: - Body temperature over 38 or under 36 degrees Celsius - Heart rate greater than 90 beats/minute - Respiratory rate greater than 20 breaths/minute or PaCO2 less than 32 mmHg - White blood cell count greater than 12,000 or less than 4,000 /microliters or over 10% of immature forms (bands)Mouton, C. P., Bazaldua, O., Pierce, B., & Espino, D. V. (2001). Common infections in older adults. American Family Physician, 63(2), 257-269. https://www.aafp.org/afp/2001/0115/p257.html Even though the purpose of SIRS is to defend against a noxious stressor, the uncontrolled release of massive amounts of cytokines, called cytokine storm, can lead to organ dysfunction and even death.Mouton, C. P., Bazaldua, O., Pierce, B., & Espino, D. V. (2001). Common infections in older adults. American Family Physician, 63(2), 257-269. https://www.aafp.org/afp/2001/0115/p257.html Sepsis refers to SIRS that is caused by an infection. Sepsis occurs when an existing infection triggers an exaggerated inflammatory reaction throughout the body. If left untreated, sepsis causes tissue and organ damage. It can quickly spread to multiple organs and is a life-threatening medical emergency. Sepsis causing damage to one or more organs (such as the kidneys) is called severe sepsis. Severe sepsis can lead to septic shock, a life-threatening decrease in blood pressure (systolic pressure <90 mm Hg) that prevents cells and other organs from receiving enough oxygen and nutrients, causing multi-organ failure and death. See Figure 9.12This work is derivative of “Sepsis_Steps.png” by Hadroncastle and is licensed under CC BY-SA 4.0 for an illustration of the progression of sepsis from SIRS to septic shock. Unfortunately, almost any type of infection in any individual can lead to sepsis. Infections that lead to sepsis most often start in the lungs, urinary tract, gastrointestinal tract, or skin. Some people are especially at risk for developing sepsis, such as adults over age 65; children younger than one year old; people who are immunocompromised or have chronic medical conditions, such as diabetes, lung disease, cancer, and kidney disease; and survivors of a previous sepsis episode.Centers for Disease Control and Prevention. (2020, August 18). Sepsis. https://www.cdc.gov/sepsis/index.html In addition to exhibiting signs of SIRS, patients with sepsis may also have additional signs such as elevated fever and shivering, confusion, shortness of breath, pain or discomfort, and clammy or sweaty skin. Diligent nursing care is vital for recognizing when patients with a diagnosed infection are developing sepsis. It is important to know the early signs of SIRS and sepsis and to act quickly by notifying the health care provider and/or following sepsis protocols in place at your health care facility.Centers for Disease Control and Prevention. (2020, August 18). Sepsis. https://www.cdc.gov/sepsis/index.html Use the following hyperlinks to read more information about sepsis. - Read more information about sepsis at the CDC’s Sepsis web page. - Read the CDC infographic on Protect Your Patients from Sepsis. - Read an article about caring for patients with sepsis titled Something Isn’t Right: The Subtle Changes of Early Deterioration. - Read more about the Surviving Sepsis Campaign with early recognition and treatment of sepsis using the Hour-1 Bundle. Toxins Some pathogens release toxins that are biological poisons that assist in their ability to invade and cause damage to tissues. For example, Botulinum toxin (also known as botox) is a neurotoxin produced by the gram-positive bacterium Clostridium botulinum that is an acutely toxic substance because it blocks the release of the neurotransmitter acetylcholine. The toxin’s blockage of acetylcholine results in muscle paralysis with the potential to stop breathing due to its effect on the respiratory muscles. This condition is referred to as botulism, a type of food poisoning that can be caused by improper sterilization of canned foods. However, because of its paralytic action, low concentrations of botox are also used for beneficial purposes such as cosmetic procedures to remove wrinkles and in the medical treatment of overactive bladder.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction Another type of neurotoxin is tetanus toxin, which is produced by the gram-positive bacterium Clostridium tetani. Tetanus toxin inhibits the release of GABA, resulting in permanent muscle contraction. The first symptom of tetanus is typically stiffness of the jaw. Violent muscle spasms in other parts of the body follow, typically culminating with respiratory failure and death. Because of the severity of tetanus, it is important for nurses to encourage individuals to regularly receive tetanus vaccination boosters throughout their lifetimes.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction Stages of Disease When a pathogen becomes an infection-causing disease, there are five stages of disease, including the incubation, prodromal, illness, decline, and convalescence periods. See Figure 9.13“unknown image” by OpenStax is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/15-1-characteristics-of-infectious-disease for an illustration of the stages of disease. Incubation Period The incubation period occurs after the initial entry of the pathogen into the host when it begins to multiply, but there are insufficient numbers of the pathogen present to cause signs and symptoms of disease. Incubation periods can vary from a day or two in acute disease to months or years in chronic disease, depending upon the pathogen. Factors involved in determining the length of the incubation period are diverse and can include virulence of the pathogen, strength of the host immune defenses, site of infection, and the amount of the pathogen received during exposure. During this incubation period, the patient is unaware that a disease is beginning to develop.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction Prodromal Period The prodromal period occurs after the incubation period. During this phase, the pathogen continues to multiply, and the host begins to experience general signs and symptoms of illness caused from activation of the nonspecific innate immunity, such as not feeling well (malaise), low-grade fever, pain, swelling, or inflammation. These signs and symptoms are often too general to indicate a particular disease is occurring.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction Acute Phase Following the prodromal period is the period of acute illness, during which the signs and symptoms of a specific disease become obvious and can become severe. This period of acute illness is followed by the period of decline as the immune system overcomes the pathogen. The number of pathogen particles begins to decline and thus the signs and symptoms of illness begin to decrease. However, during the decline period, patients may become susceptible to developing secondary infections because their immune systems have been weakened by the primary infection.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction Convalescent Period The final period of disease is known as the convalescent period. During this stage, the patient generally returns to normal daily functioning, although some diseases may inflict permanent damage that the body cannot fully repair.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction For example, if a strep infection becomes systemic and causes a secondary infection of the patient’s heart valves, the heart valves may never return to full function and heart failure may develop. Infectious diseases can be contagious during all five of the periods of disease. The transmissibility of an infection during these periods depends upon the pathogen and the mechanisms by which the disease develops and progresses. For example, with many viral diseases associated with rashes (e.g., chicken pox, measles, rubella, roseola), patients are contagious during the incubation period up to a week before the rash develops. In contrast, with many respiratory infections (e.g., colds, influenza, diphtheria, strep throat, and pertussis) the patient becomes contagious with the onset of the prodromal period. Depending upon the pathogen, the disease, and the individual infected, transmission can still occur during the periods of decline, convalescence, and even long after signs and symptoms of the disease disappear. For example, an individual recovering from a diarrheal disease may continue to carry and shed the pathogen in feces for a long time, posing a risk of transmission to others through direct or indirect contact.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction Types of Infection Acute vs. Chronic Acute, self-limiting infections develop rapidly and generally last only 10-14 days. Colds and ear infections are considered acute, self-limiting infections. See Figure 9.14“392131387-huge.jpg” by Alexandr Litovchenko is used under license from Shutterstock.com for an image of an individual with an acute, self-limiting infection. Conversely, chronic infections may persist for months. Hepatitis and mononucleosis are examples of chronic infections.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction Healthcare-Associated Infections An infection that is contracted in a health care facility or under medical care is known as a healthcare-associated infection (HAI), formerly referred to as a nosocomial infection. On any given day, about one in 31 hospital patients has at least one healthcare-associated infection. HAIs increase the cost of care and delay recovery and are associated with permanent disability, loss of wages, and even death.Centers for Disease Control and Prevention. (2016, March 4). Healthcare-associated infections. https://www.cdc.gov/hai/index.html,U.S. Department of Health and Human Services. (2020, January 15). Health care-associated infections. https://health.gov/our-work/health-care-quality/health-care-associated-infections The U.S. Department of Health and Human Services (HHS) has established these goals to reduce these common healthcare-associated infections in health care institutions: - Reduce central line-associated bloodstream infections (CLABSI) - Reduce catheter-associated urinary tracts infections (CAUTI) - Reduce the incidence of invasive health care-associated Methicillin-resistant Staphylococcus aureus (MRSA) - Reduce hospital-onset MRSA bloodstream infections - Reduce hospital-onset Clostridium difficile infections - Reduce the rate of Clostridium difficile hospitalizations - Reduce surgical site infections (SSI)Centers for Disease Control and Prevention. (2016, March 4). Healthcare-associated infections. https://www.cdc.gov/hai/index.html,U.S. Department of Health and Human Services. (2020, January 15). Health care-associated infections. https://health.gov/our-work/health-care-quality/health-care-associated-infections Blood-borne Pathogens Blood-borne pathogens are potentially present in a patient’s blood and body fluids, placing other patients and health care providers at risk for infection if they are exposed. The most common blood-borne pathogens include hepatitis B, hepatitis C, and human immunodeficiency virus (HIV). When a nurse or other health care worker experiences exposure due to a needlestick injury or the splashing of body fluids, it should be immediately reported so that careful monitoring can occur. When the source of the exposure is known, the health care worker and patient are initially tested. Repeat testing and medical prophylaxis may be warranted for the health care worker, depending on the results.Centers for Disease Control and Prevention. (2016, October 5). Bloodborne infectious diseases: HIV/AIDS, hepatitis B, hepatitis C; General resources on bloodborne pathogens. https://www.cdc.gov/niosh/topics/bbp/genres.html,Centers for Disease Control and Prevention. (2016, October 5). Bloodborne infectious diseases: HIV/AIDS, hepatitis B, hepatitis C; Preventing needlesticks and sharps injuries. https://www.cdc.gov/niosh/topics/bbp/sharps.html Needlesticks and sharps injuries are the most common causes of blood-borne pathogen exposure for nurses. The National Institute for Occupational Safety and Health (NIOSH) has developed a comprehensive Sharps Injury Prevention Program to decrease needle and sharps injury in health care workers.Centers for Disease Control and Prevention. (2016, October 5). Bloodborne infectious diseases: HIV/AIDS, hepatitis B, hepatitis C; General resources on bloodborne pathogens. https://www.cdc.gov/niosh/topics/bbp/genres.html,Centers for Disease Control and Prevention. (2016, October 5). Bloodborne infectious diseases: HIV/AIDS, hepatitis B, hepatitis C; Preventing needlesticks and sharps injuries. https://www.cdc.gov/niosh/topics/bbp/sharps.html Needles are also used in the community, such as at home, work, in airports, or public restrooms as individuals use needles to administer prescribed medications or to inject illegal drugs. Nurses can help prevent needlestick and sharps injuries in their community by implementing a community needle disposal program. Read more about needlestick and sharps injury prevention in the “Aseptic Technique” chapter in Open RN Nursing Skills. 9.5 Treating Infection Open Resources for Nursing (Open RN) Antibiotics are used to treat bacterial infections. They either kill bacteria or stop them from reproducing, allowing the body’s natural defenses to eliminate the pathogens. Used properly, antibiotics can save lives. However, growing antibiotic resistance is curbing the effectiveness of these drugs. Taking an antibiotic as directed, even after symptoms disappear, is key to curing an infection and preventing the development of resistant bacteria. Antibiotics do not work against viral infections such as colds or influenza. Antiviral drugs, which fight infection either by inhibiting a virus’s ability to reproduce or by strengthening the body’s immune response to the infection, are used for some viral infections. There are several different classes of drugs in the antiviral family, and each is used for specific kinds of viral infections. Antifungal medications are used to treat fungal and yeast infections. Antiparasitic medication is used to treat parasites, and anthelmintic medication is used to treat worm infections. Antibiotic Stewardship Microorganisms can quickly develop new features that make them resistant to the drugs that were once able to kill them. People infected with antibiotic-resistant organisms are more likely to have longer, more expensive hospital stays and may be more likely to die as a result of an infection.Centers for Disease Control and Prevention. (2019, August 15). Core elements of antibiotic stewardship. https://www.cdc.gov/antibiotic-use/core-elements/index.html Misuse of antimicrobials is one of the world’s most pressing public health problems because of these consequences. Many factors contribute to resistance, including overprescription of antibiotics for nonbacterial infections, use of inappropriate antibiotics for the infectious microorganism, and lack of completion of prescribed antibiotic therapy. Some infections, such as Methicillin-resistant Staphylococcus aureus (MRSA) and Vancomycin-resistant Enterococci (VRE), are becoming increasingly hard to treat and some microorganisms cannot be effectively destroyed by any known antibiotic.Centers for Disease Control and Prevention. (2019, August 15). Core elements of antibiotic stewardship. https://www.cdc.gov/antibiotic-use/core-elements/index.html Antimicrobial stewardship is a coordinated program that promotes the appropriate use of antimicrobials (including antibiotics), improves patient outcomes, reduces microbial resistance, and decreases the spread of infections caused by multidrug-resistant organisms. The Centers for Disease Control (CDC) has developed core elements for antibiotic stewardship to serve as a guide to improve antibiotic use for improved patient safety and outcomes.Centers for Disease Control and Prevention. (2019, August 15). Core elements of antibiotic stewardship. https://www.cdc.gov/antibiotic-use/core-elements/index.html See Figure 9.15“HowAntibioticResistanceHappens.jpg” by CDC is licensed under CC0. Access for free at https://www.cdc.gov/antibiotic-use/community/materials-references/graphics.html. for an image from the CDC explaining antibiotic resistance. The nurse plays an important role in antimicrobial stewardship through patient education. For example, many patients expect to receive an antibiotic when they seek treatment for an illness or symptom. However, because antibiotics are only effective in treating bacteria, the patient should be educated regarding effective treatment for the type of pathogen causing their symptoms. If an antibiotic is prescribed, patients should be advised to complete the entire course of therapy or contact their provider if they are unable to do so. For example, patients often feel better after a few days of treatment and decide not to take the remaining medication, or they may experience side effects from the antibiotic (such as nausea and diarrhea) and stop taking the medication. All of these behaviors can lead to antibiotic resistance and should be addressed when providing patient education regarding prescribed antibiotic therapy. 9.6 Preventing Infection Open Resources for Nursing (Open RN) In addition to recognizing signs of infection and educating patients about the treatment of their infection, nurses also play an important role in preventing the spread of infection. A cyclic process known as the chain of infection describes the transmission of an infection. By implementing interventions to break one or more links in the chain of infection, the spread of infection can be stopped. See Figure 9.16“Chain_of_Infection.png” by Genieieiop is licensed under CC BY-SA 4.0 for an illustration of the links within the chain of infection. These links are described as the following: - Infectious Agent: A causative organism, such as bacteria, virus, fungi, parasite. - Reservoir: A place where the organism grows, such as in blood, food, or a wound. - Portal of Exit: The method by which the organism leaves the reservoir, such as through respiratory secretions, blood, urine, breast milk, or feces. - Mode of Transmission: The vehicle by which the organism is transferred such as physical contact, inhalation, or injection. The most common vehicles are respiratory secretions spread by a cough, sneeze, or on the hands. A single sneeze can send thousands of virus particles into the air. - Portal of Entry: The method by which the organism enters a new host, such as through mucous membranes or nonintact skin. - Susceptible Host: The susceptible individual the organism has invaded.Centers for Disease Control and Prevention. (2012, May 18). Lesson 1: Introduction to epidemiology. https://www.cdc.gov/csels/dsepd/ss1978/lesson1/section10.html For a pathogen to continue to exist, it must put itself in a position to be transmitted to a new host, leaving the infected host through a portal of exit. Similar to portals of entry, the most common portals of exit include the skin and the respiratory, urogenital, and gastrointestinal tracts. Coughing and sneezing can expel thousands of pathogens from the respiratory tract into the environment. Other pathogens are expelled through feces, urine, semen, and vaginal secretions. Pathogens that rely on insects for transmission exit the body in the blood extracted by a biting insect.This work is a derivative of Microbiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/microbiology/pages/1-introduction The pathogen enters a new individual via a portal of entry, such as mucous membranes or nonintact skin. If the individual has a weakened immune system or their natural defenses cannot fend off the pathogen, they become infected. Interventions to Break the Chain of Infection Infections can be stopped from spreading by interrupting this chain at any link. Chain links can be broken by disinfecting the environment, sterilizing medical instruments and equipment, covering coughs and sneezes, using good hand hygiene, implementing standard and transmission-based precautions, appropriately using personal protective equipment, encouraging patients to stay up-to-date on vaccines (including the flu shot), following safe injection practices, and promoting the optimal functioning of the natural immune system with good nutrition, rest, exercise, and stress management. Disinfection and Sterilization Disinfection and sterilization are used to kill microorganisms and remove harmful pathogens from the environment and equipment to decrease the chance of spreading infection. Disinfection is the removal of microorganisms. However, disinfection does not destroy all spores and viruses. Sterilization is a process used on equipment and the environment to destroy all pathogens, including spores and viruses. Sterilization methods include steam, boiling water, dry heat, radiation, and chemicals. Because of the harshness of these sterilization methods, skin can only be disinfected and not sterilized.Centers for Disease Control and Prevention. (2019, May 24). Disinfection and sterilization. https://www.cdc.gov/infectioncontrol/guidelines/disinfection/index.html Standard and Transmission-Based Precautions To protect patients and health care workers from the spread of pathogens, the CDC has developed precautions to use during patient care that address portals of exit, methods of transmission, and portals of entry. These precautions include standard precautions and transmission-based precautions. Standard Precautions Standard precautions are used when caring for all patients to prevent healthcare-associated infections. According to the Centers for Disease Control and Prevention (CDC), standard precautions are the minimum infection prevention practices that apply to all patient care, regardless of suspected or confirmed infection status of the patient, in any setting where health care is delivered. These precautions are based on the principle that all blood, body fluids (except sweat), nonintact skin, and mucous membranes may contain transmissible infectious agents. These standards reduce the risk of exposure for the health care worker and protect the patient from potential transmission of infectious organisms.Centers for Disease Control and Prevention. (2016, January 26). Standard precautions for all patient care. https://www.cdc.gov/infectioncontrol/basics/standard-precautions.html See Figure 9.17“hand-disinfection-4954840_960_720.jpg” by KlausHausmann is licensed under CC0 for an image of some of the components of standard precautions. Current standard precautions according to the CDC include the following: - Appropriate hand hygiene - Use of personal protective equipment (e.g., gloves, gowns, masks, eyewear) whenever infectious material exposure may occur - Appropriate patient placement and care using transmission-based precautions when indicated - Respiratory hygiene/cough etiquette - Proper handling and cleaning of environment, equipment, and devices - Safe handling of laundry - Sharps safety (i.e., engineering and work practice controls) - Aseptic technique for invasive nursing procedures such as parenteral medication administrationCenters for Disease Control and Prevention. (2016, January 26). Standard precautions for all patient care. https://www.cdc.gov/infectioncontrol/basics/standard-precautions.html Hand Hygiene Hand hygiene, although simple, is still the best and most effective way to prevent the spread of infection. The 2021 National Patient Safety Goals from The Joint Commission encourages infection prevention strategy practices such as implementing the hand hygiene guidelines from the Centers for Disease Control.Centers for Disease Control and Prevention. (2019, April 29). Hand hygiene in healthcare settings. https://www.cdc.gov/handhygiene/ Accepted methods for hand hygiene include using either soap and water or alcohol-based hand sanitizer. It is essential for all health care workers to use proper hand hygiene at the appropriate times, such as the following: - Immediately before touching a patient - Before performing an aseptic task or handling invasive devices - Before moving from a soiled body site to a clean body site on a patient - After touching a patient or their immediate environment - After contact with blood, body fluids, or contaminated surfaces (with or without glove use) - Immediately after glove removalCenters for Disease Control and Prevention. (2019, April 29). Hand hygiene in healthcare settings. https://www.cdc.gov/handhygiene/ Hand hygiene also includes health care workers keeping their nails short with tips less than 0.5 inches and no nail polish. Nails should be natural, and artificial nails or tips should not be worn. Artificial nails and chipped nail polish have been associated with a higher level of pathogens carried on the hands of the nurse despite hand hygiene.Blackburn, L., Acree, K., Bartley, J., DiGiannantoni, E., Renner, E., & Sinnott, L. T. (2020). Microbial growth on the nails of direct patient care nurses wearing nail polish. Nursing Oncology Forum, 47(2), 155-164. https://doi.org/10.1188/20.onf.155-164 Respiratory Hygiene/Cough Etiquette Respiratory hygiene is targeted at patients, accompanying family members and friends, and staff members with undiagnosed transmissible respiratory infections. It applies to any person with signs of illness, including cough, congestion, or increased production of respiratory secretions when entering a health care facility. The elements of respiratory hygiene include the following: - Education of health care facility staff, patients, and visitors - Posted signs, in language(s) appropriate to the population served, with instructions to patients and accompanying family members or friends - Source control measures for a coughing person (e.g., covering the mouth/nose with a tissue when coughing and prompt disposal of used tissues, or applying surgical masks on the coughing person to contain secretions) - Hand hygiene after contact with one’s respiratory secretions - Spatial separation, ideally greater than 3 feet, of persons with respiratory infections in common waiting areas when possibleCenters for Disease Control and Prevention. (2016, January 26). Standard precautions for all patient care. https://www.cdc.gov/infectioncontrol/basics/standard-precautions.html Health care personnel are advised to wear a mask and use frequent hand hygiene when examining and caring for patients with signs and symptoms of a respiratory infection. Health care personnel who have a respiratory infection are advised to stay home or avoid direct patient contact, especially with high-risk patients. If this is not possible, then a mask should be worn while providing patient care.Centers for Disease Control and Prevention. (2016, January 26). Standard precautions for all patient care. https://www.cdc.gov/infectioncontrol/basics/standard-precautions.html Personal Protective Equipment Personal Protective Equipment (PPE) includes gloves, gowns, face shields, goggles, and masks used to prevent the spread of infection to and from patients and health care providers. See Figure 9.18“U.S. Navy Doctors, Nurses and Corpsmen Treat COVID Patients in the ICU Aboard USNS Comfort<PHONE_NUMBER>8).jpg” by Navy Medicine is licensed under CC0. for an image of a nurse wearing PPE. Depending upon the anticipated exposure and type of pathogen, PPE may include the use of gloves, a fluid-resistant gown, goggles or a face shield, and a mask or respirator. When used while caring for a patient with transmission-based precautions, PPE supplies are typically stored in an isolation cart next to the patient’s room. Transmission-Based Precautions In addition to standard precautions, transmission-based precautions are used for patients with documented or suspected infection of highly-transmissible pathogens, such as C. difficile (C-diff), Methicillin-resistant Staphylococcus aureus (MRSA), Vancomycin-resistant enterococci (VRE), Respiratory Syncytial Virus (RSV), measles, and tuberculosis (TB). For patients with these types of pathogens, standard precautions are used along with specific transmission-based precautions.Siegel, J. D., Rhinehart, E., Jackson, M., Chiarello, L., & Healthcare Infection Control Practices Advisory Committee. (2019, July 22). 2007 guideline for isolation precautions: Preventing transmission of infectious agents in healthcare settings. https://www.cdc.gov/infectioncontrol/guidelines/isolation/index.html There are three categories of transmission-based precautions: contact precautions, droplet precautions, and airborne precautions. Transmission-based precautions are used when the route(s) of transmission of a specific disease are not completely interrupted using standard precautions alone. Some diseases, such as tuberculosis, have multiple routes of transmission so more than one transmission-based precaution category must be implemented. See Table 9.6 outlining the categories of transmission precautions with associated PPE and other precautions. When possible, patients with transmission-based precautions should be placed in a single occupancy room with dedicated patient care equipment (e.g., blood pressure cuffs, stethoscope, and thermometer stay in the patient’s room). A card is posted outside the door alerting staff and visitors to required precautions before entering the room. See Figure 9.19“Contact_Precautions_poster.pdf” by U.S. Centers for Disease Control and Prevention is in the Public Domain for an example of signage used for a patient with contact precautions. Transport of the patient and unnecessary movement outside the patient room should be limited. When transmission-based precautions are implemented, it is also important for the nurse to make efforts to counteract possible adverse effects of these precautions on patients, such as anxiety, depression, perceptions of stigma, and reduced contact with clinical staff.Siegel, J. D., Rhinehart, E., Jackson, M., Chiarello, L., & Healthcare Infection Control Practices Advisory Committee. (2019, July 22). 2007 guideline for isolation precautions: Preventing transmission of infectious agents in healthcare settings. https://www.cdc.gov/infectioncontrol/guidelines/isolation/index.html Table 9.6 Transmission-Based PrecautionsSiegel, J. D., Rhinehart, E., Jackson, M., Chiarello, L., & Healthcare Infection Control Practices Advisory Committee. (2019, July 22). 2007 guideline for isolation precautions: Preventing transmission of infectious agents in healthcare settings. https://www.cdc.gov/infectioncontrol/guidelines/isolation/index.html \| Precaution \| Implementation \| PPE and Other Precautions \| \|---\|---\|---\| \| Contact \| Known or suspected infections with increased risk for contact transmission (e.g., draining wounds, fecal incontinence) or with epidemiologically important organisms, such as C-diff, MRSA, VRE, or RSV \| Gloves Gown Dedicated equipment Limit patient transport out of room Prioritized disinfection of the room Note: Use only soap and water for hand hygiene in patients with C. difficile infection. \| \| Droplet \| Known or suspected infection with pathogens transmitted by large respiratory droplets generated by coughing, sneezing, or talking, such as influenza or pertussis \| Mask Goggles or face shield \| \| Airborne \| Known or suspected infection with pathogens transmitted by small respiratory droplets, such as measles and coronavirus \| Fit-tested N-95 respirator Airborne infection isolation room Single-patient room Patient door closed Restricted susceptible personnel room entry \| Patient Transport Several principles are used to guide transport of patients requiring transmission-based precautions. In the inpatient and residential settings, these principles include the following: - Limit transport for essential purposes only, such as diagnostic and therapeutic procedures that cannot be performed in the patient’s room - When transporting, use appropriate barriers on the patient consistent with the route and risk of transmission (e.g., mask, gown, covering the affected areas when infectious skin lesions or drainage is present) - Notify health care personnel in the receiving area of the impending arrival of the patient and of the precautions necessary to prevent transmissionSiegel, J. D., Rhinehart, E., Jackson, M., Chiarello, L., & Healthcare Infection Control Practices Advisory Committee. (2019, July 22). 2007 guideline for isolation precautions: Preventing transmission of infectious agents in healthcare settings. https://www.cdc.gov/infectioncontrol/guidelines/isolation/index.html Enteric Precautions Enteric precautions are used when there is the presence, or suspected presence, of gastrointestinal pathogens such as Clostridium difficile (C-diff) or norovirus. These pathogens are present in feces, so health care workers should always wear a gown in the patient room to prevent inadvertent fecal contamination of their clothing from contact with contaminated surfaces. In addition to contact precautions, enteric precautions include the following: - Using only soap and water for hand hygiene. Do not use hand sanitizer because it is not effective against C-diff. - Using a special disinfecting process. Special disinfecting should be used after patient discharge and includes disinfection of the mattress. Reverse Isolation Reverse isolation, also called neutropenic precautions, is used for patients who have compromised immune systems and low neutrophil levels. This type of isolation protects the patient from pathogens in their environment. In addition to using contact precautions to protect the patient, reverse isolation precautions include the following: - Meticulous hand hygiene by all visitors, staff, and the patient - Frequently monitoring for signs and symptoms of infection and sepsis - Not allowing live plants, fresh flowers, fresh raw fruits or vegetables, sushi, deli foods, or cheese into the room due to bacteria and fungi - Placement in a private room or a positive pressure room - Limited transport and movement of the patient outside of the room - Masking of the patient for transport with a surgical maskCenters for Disease Control and Prevention. (n.d.). What you need to know: Neutropenia and risk for infection. https://www.cdc.gov/cancer/preventinfections/pdf/neutropenia.pdf Psychological Effects of Isolation Although the use of transmission-based precautions is needed to prevent the spread of infection, it is important for nurses to be aware of the potential psychological impact on the patient. Research has shown that isolation can cause negative impact on patient mental well-being and behavior, including higher scores for depression, anxiety, and anger among isolated patients. It has also been found that health care workers spend less time with patients in isolation, resulting in a negative impact on patient safety.U.S. Department of Health and Human Services. (2020, January 15). Health care-associated infections. https://health.gov/our-work/health-care-quality/health-care-associated-infections Patient and family education at the time of instituting transmission-based precautions is a critical component of the process to reduce anxiety and distress. Patients often feel stigmatized when placed in isolation, so it is important for them to understand the rationale of the precautions to keep themselves and others free from the spread of disease. Preparing patients emotionally will also help decrease their anxiety and help them cope with isolation.U.S. Department of Health and Human Services. (2020, January 15). Health care-associated infections. https://health.gov/our-work/health-care-quality/health-care-associated-infections It is also important to provide distractions from boredom, such as music, television, video games, magazines, or books, as appropriate. Aseptic and Sterile Techniques In addition to using standard precautions and transmission-based precautions, aseptic technique (also called medical asepsis) is used to prevent the transfer of microorganisms from one person or object to another during a medical procedure. For example, a nurse administering parenteral medication or performing urinary catheterization uses aseptic technique. When performed properly, aseptic technique prevents contamination and transfer of pathogens to the patient from caregiver hands, surfaces, and equipment during routine care or procedures. It is important to remember that potentially infectious microorganisms can be present in the environment, on instruments, in liquids, on skin surfaces, or within a wound.Centers for Disease Control and Prevention. (2020, August 10). Glossary of terms for infection prevention and control in dental settings. https://www.cdc.gov/oralhealth/infectioncontrol/glossary.htm There is often misunderstanding between the terms aseptic technique and sterile technique in the health care setting. Both asepsis and sterility are closely related with the shared concept being the removal of harmful microorganisms that can cause infection. In the most simplistic terms, aseptic technique involves creating a protective barrier to prevent the spread of pathogens, whereas sterile technique is a purposeful attack on microorganisms. Sterile technique (also called surgical asepsis) seeks to eliminate every potential microorganism in and around a sterile field while also maintaining objects as free from microorganisms as possible. Sterile fields are implemented during surgery, as well as during nursing procedures such as the insertion of a urinary catheter, changing dressings on open wounds, and performing central line care. See Figure 9.20“226589236-huge.jpg” by TORWAISTUDIO is used under license from Shutterstock.com for an image of a sterile field during surgery. Sterile technique requires a combination of meticulous hand washing, creating and maintaining a sterile field, using long-lasting antimicrobial cleansing agents such as Betadine, donning sterile gloves, and using sterile devices and instruments.This work is a derivative of StatPearls by Tennant and Rivers and is licensed under CC BY 4.0. Read additional information about aseptic and sterile technique in the “Aseptic Technique” in Open RN Nursing Skills. Read a continuing education article about Sterile Technique and surgical scrubbing. Other Hygienic Patient Care Interventions In addition to implementing standard and transmission-based precautions and utilizing aseptic and sterile technique when performing procedures, nurses implement many interventions to place a patient in the best health possible to prevent an infection or treat infection. These interventions include actions like encouraging rest and good nutrition, teaching stress management, providing good oral care, encouraging daily bathing, and changing linens. It is also important to consider how gripper socks, mobile devices, and improper glove usage can contribute to the transmission of pathogens. Oral Care Patient hygiene is important in the prevention and spread of infection. Oral care should be performed in the morning, after meals, and before bed.Ackley, B., Ladwig, G., Makic, M. B., Martinez-Kratz, M., & Zanotti, M. (2020). Nursing diagnosis handbook: An evidence-based guide to planning care (12th ed.). Elsevier. pp. 546-552, 828-832. Daily Bathing Daily bathing is another intervention that may be viewed as time-consuming and receive low priority, but it can have a powerful impact on decreasing the spread of infection. Studies have shown a significant decrease in healthcare-associated infections with daily bathing using chlorhexidine gluconate (CHG) wipes or solution. The use of traditional soap and water baths do not reduce infection rates as significantly as CHG products, and wash basins have also been shown to be a reservoir for pathogens.Salamone, K., Yacoub, E., Mahoney, A. M., & Edward, K. L. (2013). Oral care of hospitalised older patients in the acute medical setting. Nursing Research and Practice, 2013, 827670. https://doi.org/10.1155/2013/827670 Linens Changing bed linens, towels, and a gown regularly eliminates potential reservoirs of bacteria. Fresh linens also promote patient comfort. Gripper Socks Have you ever thought about what happens to the bed linens when a patient returns from a walk in the hallway with gripper socks and gets back into bed with these socks? Research demonstrates that pathogens from the floor are transferred to the patient bed linens from the gripper socks. Nurses should remove gripper socks that were used for walking before patients climb into bed. They should also throw the socks away when the patient is discharged instead of sending them home.Welle, M. K., Bliha, M., DeLuca, J., Frauhiger, A., & Lamichhane-Khadka, R. Bacteria on the soles of patient-issued nonskid slipper socks: An overlooked pathogen spread threat? Orthopedic Nursing, 38(1), 33-40. https://doi.org/10.1097/nor.0000000000000516 Cellular Phones and Mobile Devices Research has shown that cell phones and mobile devices carry many pathogens and are dirtier than a toilet seat or the bottom of a shoe. Patients, staff, and visitors routinely bring these mobile devices into health care facilities, which can cause the spread of disease. Nurses should frequently wipe mobile devices with disinfectant. They should encourage patients and visitors to disinfect phones frequently and avoid touching the face after having touched a mobile device.Morubagal, R. R., Shivappa, S. G., Mahale, R. P., & Neelambike, S. M. (2017). Study of bacterial flora associated with mobile phones of healthcare workers and non-healthcare workers. Iranian Journal of Microbiology, 9(3), 143–151. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5719508/ Gloves Although gloves are used to prevent the spread of infection, they can also contribute to the spread of infection if used improperly. For example, research has shown that hand hygiene opportunities are being missed because of the overuse of gloves. For example, a nurse may don gloves to suction a patient but neglect to remove them and perform hand hygiene before performing the next procedure on the same patient. This can potentially cause the spread of secondary infection. The World Health Organization (WHO) states that gloves should be worn when there is an expected risk of exposure to blood or body fluids or to protect the hands from chemicals and hazardous drugs, but hand hygiene is the best method of disease prevention and is preferred over wearing gloves when the exposure risk is minimal. Nurses have the perception that wearing gloves provides extra protection and cleanliness. However, the opposite is true. Nonsterile gloves have a high incidence of contamination with a range of bacteria, which means that a gloved hand is dirtier than a washed hand. Research has shown that nearly 40% of the times that gloves are used in patient care, there is cross contamination. The most striking example of cross contamination includes situations when gloves are used for toileting a patient and not being removed before touching other surfaces or the patient.Burdsall, D. P., Gardner, S. E., Cox, T., Schweizer, M., Culp, K. R., Steelman, V. M., & Herwaldt, L. A. (2017). Exploring inappropriate certified nursing assistant glove use in long-term care. American Journal of Infection Control, 45(9), 940-945. https://doi.org/10.1016/j.ajic.2017.02.017,Jain, S., Clezy, K., & McLaws, M. L. Glove: Use for safety or overuse? American Journal of Infection Control, 45(12), 1407-1410. https://doi.org/10.1016/j.ajic.2017.08.029,Welle, M. K., Bliha, M., DeLuca, J., Frauhiger, A., & Lamichhane-Khadka, R. Bacteria on the soles of patient-issued nonskid slipper socks: An overlooked pathogen spread threat? Orthopedic Nursing, 38(1), 33-40. https://doi.org/10.1097/nor.0000000000000516 Glove-related contact dermatitis has also become an important issue in recent years as more and more nurses are experiencing damage to the hands. Contact dermatitis can develop from repeated use of gloves and develops as dry, itchy, irritated areas on the skin of the hands. See Figure 9.21“Dermatitis2015.jpg” by James Heilman, MD is licensed under CC BY-SA 4.0 for an image of contact dermatitis from gloves. Because the skin is the first line of defense in preventing pathogens from entering the body, maintaining intact skin is very important to prevent nurses from exposure to pathogens. 9.7 Applying the Nursing Process Open Resources for Nursing (Open RN) Now that we have discussed the pathophysiology of our immune system and interventions to treat and prevent infection, let’s apply this information to using the nursing process when providing patient care. Assessment When assessing an individual who is feeling ill but has not yet been diagnosed with an infection, general symptoms associated with the prodromal period of disease may be present due to the activation of the immune system. These symptoms include a feeling of malaise (not feeling well), headache, fever, and lack of appetite. As an infection moves into the acute phase of disease, more specific symptoms and signs related to the specific type of infection will occur. A fever is a common sign of inflammation and infection. A temperature of 38 degrees Celsius (100.4 degrees F) is generally considered a low-grade fever, and a temperature of 38.3 degrees Celsius (101 degrees F) is considered a fever.Abad, C., Fearday, A., & Safdar, N. (2010). Adverse effects of isolation in hospitalised patients: A systematic review. The Journal of Hospital Infection, 76(2), 97-102. https://doi.org/10.1016/j.jhin.2010.04.027 As discussed earlier in this chapter, fever is part of the nonspecific innate immune response and can be beneficial in destroying pathogens. However, extremely elevated temperatures can cause cell and organ damage, and prolonged fever can cause dehydration. Infection raises the metabolic rate, causing an increased heart rate. The respiratory rate may also increase as the body rids itself of carbon dioxide created during increased metabolism. However, be aware that an elevated heart rate above 90 and a respiratory rate above 20 are also criteria for systemic inflammatory response syndrome (SIRS) in patients with an existing infection. As an infection develops, the lymph nodes that drain that area often become enlarged and tender. The swelling indicates that the lymphocytes and macrophages in the lymph node are fighting the infection. If a skin infection is developing, general signs of inflammation, such as redness, warmth, swelling, and tenderness, will occur at the site. As white blood cells migrate to the site, purulent drainage may occur. Some viruses, bacteria, and toxins cause gastrointestinal inflammation, resulting in loss of appetite, nausea, vomiting, and diarrhea. See Table 9.7a for a comparison of expected findings on physical assessment versus unexpected findings indicating a new infectious process that requires notification of the health care provider. Table 9.7a Expected Versus Unexpected Findings on Assessment Related to Infection \| Assessment \| Expected Findings \| Unexpected Findings to Report to Health Care Provider \| \|---\|---\|---\| \| Vital Signs \| Within normal range \| New temperature over 100.4 F or 38 C. \| \| Neurological \| Within baseline level of consciousness \| New confusion and/or worsening level of consciousness. \| \| Wound or Incision \| Progressive healing of a wound with no signs of infection \| New redness, warmth, tenderness, or purulent drainage from a wound. \| \| Respiratory \| No cough or production of sputum \| New cough and/or productive cough of purulent sputum. Adventitious breath sounds (crackles, rhonchi, wheezing). New dyspnea. \| \| Genitourinary \| Urine clear, light yellow without odor \| Malodorous, cloudy, bloody urine, with increased frequency, urgency, or pain with urination. \| \| Gastrointestinal \| Good appetite and food intake; feces formed and brown \| Loss of appetite. Nausea and vomiting. Diarrhea; discolored or unusually malodorous feces. \| \| CRITICAL CONDITIONS requiring immediate notification of the provider and/or implementation of a sepsis protocol: Two or more of the following criteria in a patient with an existing infection indicate SIRS: \| Life Span Considerations Infants do not have well-developed immune systems, placing this group at higher risk of infection. Breastfeeding helps protect infants from some infectious diseases by providing passive immunity until their immune system matures. New mothers should be encouraged to breastfeed their newborns.Centers for Disease Control and Prevention. (2020, May 28). Breastfeeding, Frequently asked questions (FAQs). https://www.cdc.gov/breastfeeding/faq/index.htm On the other end of the continuum, the immune system gradually decreases in effectiveness with age, making older adults also more vulnerable to infection. Early detection of infection can be challenging in older adults because they may not have a fever or increased white blood cell count (WBC), but instead develop subtle changes like new mental status changes.Centers for Disease Control and Prevention. (2020, May 28). Breastfeeding, Frequently asked questions (FAQs). https://www.cdc.gov/breastfeeding/faq/index.htm The most common infections in older adults are urinary tract infections (UTI), bacterial pneumonia, influenza, and skin infections. Diagnostic Tests Several types of diagnostic tests may be ordered by a health care provider when a patient is suspected of having an infection, such as complete blood count with differential, Erythrocyte Sedimentation Rate (ESR), C-Reactive Protein (CRP), serum lactate levels, and blood cultures (if sepsis is suspected). Other cultures may be obtained based on the site of the suspected infection. CBC With Differential When an infection is suspected, a complete blood count with differential is usually obtained. A complete blood count (CBC) includes the red blood cell count (RBC), white blood cell count (WBC), platelets, hemoglobin, and hematocrit values. A differential provides additional information, including the relative percentages of each type of white blood cell. See Figure 9.22“Blausen_0425_Formed_Elements.png” by BruceBlaus.com staff is licensed under CC BY 3.0 for an illustration of a complete blood count with differential. When there is an infection or an inflammatory process somewhere in the body, the bone marrow produces more WBCs (also called leukocytes), releasing them into the blood where they move to the site of infection or inflammation. An increase in white blood cells is known as leukocytosis and is a sign of the inflammatory response. The normal range of WBC varies slightly from lab to lab but is generally 4,500-11,000 for adults, reported as 4.5-11.0 x 109 per liter (L).Centers for Disease Control and Prevention. (2021, January 19). Candida auris. https://www.cdc.gov/fungal/candida-auris/index.html There are five types of white blood cells, each with different functions. The differential blood count gives the relative percentage of each type of white blood cell and also reveals abnormal white blood cells. The five types of white blood cells are as follows: - Neutrophils - Eosinophils - Basophils - Lymphocytes - Monocytes Neutrophils make up the largest number of circulating WBCs. They move into an area of damaged or infected tissue where they engulf and destroy bacteria or sometimes fungi.Centers for Disease Control and Prevention. (2021, January 19). Candida auris. https://www.cdc.gov/fungal/candida-auris/index.html An elevated neutrophil count is called neutrophilia, and decreased neutrophil count is called neutropenia.LabTestsOnline.org. (2021, January 27). White blood cell count (WBC). https://labtestsonline.org/tests/white-blood-cell-count-wbc Eosinophils respond to infections caused by parasites, play a role in allergic reactions (hypersensitivities), and control the extent of immune responses and inflammation. Elevated levels of eosinophils are referred to as eosinophilia.LabTestsOnline.org. (2021, January 27). White blood cell count (WBC). https://labtestsonline.org/tests/white-blood-cell-count-wbc Basophils make up the fewest number of circulating WBCs and are thought to be involved in allergic reactions.LabTestsOnline.org. (2021, January 27). White blood cell count (WBC). https://labtestsonline.org/tests/white-blood-cell-count-wbc Lymphocytes include three types of cells, although the differential count does not distinguish among them: - B lymphocytes (B cells) produce antibodies that target and destroy bacteria, viruses, and other “non-self” foreign antigens. - T lymphocytes (T cells) mature in the thymus and consist of a few different types. Some T cells help the body distinguish between “self” and “non-self” antigens; some initiate and control the extent of an immune response, boosting it as needed and then slowing it as the condition resolves; and other types of T cells directly attack and neutralize virus-infected or cancerous cells. White blood cell count (WBC). https://labtestsonline.org/tests/white-blood-cell-count-wbc Monocytes, similar to neutrophils, move to an area of infection and engulf and destroy bacteria. They are associated with chronic rather than acute infections. They are also involved in tissue repair and other functions involving the immune system.LabTestsOnline.org. (2021, January 27). White blood cell count (WBC). https://labtestsonline.org/tests/white-blood-cell-count-wbc Care must be taken when interpreting the results of a differential. A health care provider will consider an individual’s signs and symptoms and medical history, as well as the degree to which each type of cell is increased or decreased. A number of factors can cause a transient rise or drop in the number of any type of cell. For example, bacterial infections usually produce an increase in neutrophils, but a severe infection, like sepsis, can use up the available neutrophils, causing a low number to be found in the blood. Eosinophils are often elevated in parasitic and allergic responses. Acute viral infections often cause an increased level of lymphocytes (referred to as lymphocytosis).LabTestsOnline.org. (2021, January 27). White blood cell count (WBC). https://labtestsonline.org/tests/white-blood-cell-count-wbc Erythrocyte Sedimentation Rate (ESR) An erythrocyte sedimentation rate (ESR) is a test that indirectly measures inflammation. This test measures how quickly erythrocytes or red blood cells (RBCs) settle at the bottom of a test tube that contains a blood sample. When a sample of blood is placed in a tube, the red blood cells normally settle out relatively slowly, leaving a small amount of clear plasma. The red cells settle at a faster rate when there is an increased level of proteins, such as C-reactive protein (CRP), that increases in the blood in response to inflammation. The ESR test is not diagnostic; it is a nonspecific test indicating the presence or absence of an inflammatory condition.LabTestsOnline.org. (2020, July 29). Erythrocyte sedimentation rate (ESR). https://labtestsonline.org/tests/erythrocyte-sedimentation-rate-esr C-Reactive Protein (CRP) C-Reactive Protein (CRP) levels in the blood increase when there is a condition causing inflammation somewhere in the body. CRP is a nonspecific indicator of inflammation and one of the most sensitive acute phase reactants, meaning it is released into the blood within a few hours after the start of an infection or other cause of inflammation. The level of CRP can jump as much as a thousand-fold in response to a severe bacterial infection, and its rise in the blood can precede symptoms of fever or pain.LabTestsOnline.org. (2020, August 12). C-Reactive protein (CRP). https://labtestsonline.org/tests/c-reactive-protein-crp Lactate Serum lactate levels are measured when sepsis is suspected in a patient with an existing infection. Sepsis can quickly lead to septic shock and death due to multi-organ failure so early recognition is crucial. Lactate is one of the substances produced by cells as the body turns food into energy (i.e., cellular metabolism), with the highest level of production occurring in the muscles. Normally, the level of lactate in blood is low. Lactate is produced in excess by muscle cells and other tissues when there is insufficient oxygen at the cellular level. Lactic acid can accumulate in the body and blood when it is produced faster than the liver can break it down, which can lead to lactic acidosis. Excess lactate may be produced due to several medical conditions that cause decreased transport of oxygen to the tissues, such as sepsis, hypovolemic shock, heart attack, heart failure, or respiratory distress.LabTestsOnline.org. (2020, August 12). Lactate. https://labtestsonline.org/tests/lactate Blood Culture Blood cultures are ordered when sepsis is suspected. In many facilities, lab personnel draw the blood samples for blood cultures to avoid contamination of the sample. With some infections, pathogens are only found in the blood intermittently, so a series of three or more blood cultures, as well as blood draws from different veins, may be performed to increase the chance of finding the infection. Blood cultures are incubated for several days before being reported as negative. Some types of bacteria and fungi grow more slowly than others and/or may take longer to detect if initially present in low numbers. A positive result indicates bacteria have been found in the blood (bacteremia). Other types of pathogens, such as a fungus or a virus, may also be found in a blood culture. When a blood culture is positive, the specific microbe causing the infection is identified and susceptibility testing is performed to inform the health care provider which antibiotics or other medications are most likely to be effective for treatment. It is important for nurses to remember that when new orders for both antibiotics and a blood culture are received, antibiotics should not be administered until after the blood culture is drawn. Administering antibiotics before the blood culture is drawn will impact the results and adversely affect the treatment plan. Cultures and Other Diagnostic Tests Several types of swabs and cultures may be ordered based on the site of a suspected infection, such as a nasal swab, nasopharyngeal swab, sputum culture, urine culture, and wound culture. If a lower respiratory tract infection is suspected, a chest X-ray may be ordered. Read additional information about the following topics in Open RN Nursing Skills: - Specimen Collection - Collecting urine cultures in “Facilitation of Elimination“ - Collecting wound cultures in “Wound Care“ Therapeutic Drug Monitoring When antibiotics are prescribed to treat an infection, some types of antibiotics require blood tests to ensure the dosage of the medication reaches and stays within therapeutic ranges in the blood. These tests are often referred to as peak and/or trough levels. The nurse must be aware of these orders because they impact the timing of administration of antibiotics. Diagnoses There are many NANDA-I nursing diagnoses applicable to infection. Nursing diagnoses associated with actual infections are customized based on the signs and symptoms of the specific infection (e.g., a patient with pneumonia may have an actual nursing diagnosis of Ineffective Airway Clearance). Review a nursing care planning source for a list of current NANDA-I approved nursing diagnoses based on the type of infection occurring.Herdman, T., & Kamitsuru, S. (2017). NANDA international nursing diagnoses: Definitions & classification 2018-2020 (11th ed.). Thieme Publishers. pp. 382, 405. Two common risk diagnoses are Risk for Infection for patients at risk for developing an infection and Risk for Shock for patients with an existing infection who are at risk for developing sepsis and septic shock. See Table 9.7b for the risk diagnoses of Risk for Infection and Risk for Shock. Table 9.7b NANDA-I Diagnoses Associated with Infection \| NANDA-I Diagnosis \| Definition \| Other \| \|---\|---\|---\| \| Risk for Infection \| Susceptible to invasion and multiplication of pathogenic organisms, which may compromise health \| Risk Factors \| \| Risk of Shock \| Susceptible to inadequate blood flow to the body’s tissues that may lead to life-threatening cellular dysfunction, which may compromise health \| Associated Conditions \| Examples For example, a nurse caring for a patient with an open wound assesses the wound regularly because patients with nonintact skin are always at increased risk for developing infection. A sample PES statement would be the following: “Risk for Infection as evidenced by alteration in skin integrity and insufficient knowledge to avoid exposure to pathogens.” The nurse plans to provide patient education regarding care of the wound to prevent bacterial contamination during dressing changes. Whenever caring for a patient with an existing infection, nurses know it is important to closely monitor for signs of developing SIRS and sepsis. A sample PES statement for a patient with an existing infection is as follows: “Risk for Shock as evidenced by the associated condition of infection.” Note: Recall that in NANDA-I risk diagnoses, there are no etiological factors because a vulnerability reflects the potential for developing a problem. Read more about creating PES statements for risk diagnoses in the “Nursing Process” chapter. Outcomes An example of a broad goal for all patients is the following: “The patient will remain free from infection during their health care stay.”Centers for Disease Control and Prevention. (2016, January 26). Standard precautions for all patient care. https://www.cdc.gov/infectioncontrol/basics/standard-precautions.html An example of a SMART expected outcome to prevent infection is: “The patient will demonstrate how to perform dressing changes using aseptic technique prior to discharge from the hospital.”Johnson, M., Moorhead, S., Bulechek, G., Butcher, H., Maas, M., & Swanson, E. (2012). NOC and NIC linkages to NANDA-I and clinical conditions: Supporting critical reasoning and quality care. Elsevier. p. 268. Read more about creating SMART outcomes in the “Nursing Process” chapter. Planning Interventions When planning interventions for a patient who is at risk for developing an infection, the nurse selects interventions such as those listed in the following box for “Infection Protection.” Interventions for Infection PreventionButcher, H., Bulechek, G., Dochterman, J., & Wagner, C. (2018). Nursing interventions classification (NIC). Elsevier. pp. 214, 226-227, 346.,Wilson, J., Bak, A., & Loveday, H. P. Applying human factors and ergonomics to the misuse of nonsterile clinical gloves in acute care. American Journal of Infection Control, 45(7), 779-786. https://doi.org/10.1016/j.ajic.2017.02.019. - Monitor vital signs for signs of infection - Monitor for early signs of localized and systemic infection for patients at risk - Screen all visitors for communicable disease - Encourage respiratory hygiene for patients, visitors, and staff members - Maintain aseptic technique during nursing procedures - Use sterile technique for invasive procedures or care of open wounds - Use standard precautions with all patients to prevent the spread of infection - Initiate transmission-based precautions for patients suspected of communicable infection, as appropriate - Promote sufficient nutritional intake - Encourage fluid intake, as appropriate - Encourage rest - Encourage frequent ambulation or turn immobilized patients frequently - Ensure appropriate hygienic care, including proper hand hygiene, daily bathing, oral care, and perineal care performed by either the nurse or the patient, as appropriate - Moisturize dry skin to keep it intact - Use strategies to prevent healthcare-acquired respiratory infection, such as incentive spirometry, coughing and deep breathing, positional changes, and early ambulation as appropriate - Use strategies to prevent wound infection such as changing saturated dressings to reduce the potential reservoir of bacteria - Teach the patient and family members the importance of a nutritious diet, exercise, and adequate rest to promote healing and health at home - Teach the patient and family about signs and symptoms of infection and when to report them to the health care provider - Encourage the annual influenza vaccine and keeping other recommended vaccinations up-to-date - If a patient smokes, encourage smoking cessation because smoking damages the mucociliary escalator and places the patient at increased risk for infection - Report signs and symptoms of suspected infection or sepsis to the health care provider - Suspect an infection if an older adult patient has new signs of lethargy or confusion If a patient has an infection with a fever, the nursing diagnosis Hyperthermia may be applicable. See the following box for interventions for patients with fever/hyperthermia. Interventions for Hyperthermia - Assess for associated symptoms such as diaphoresis, shaking chills (rigors) - Monitor level of consciousness - Adjust room temperature to the patient’s comfort without inducing chilling - Administer antipyretics, as appropriate (e.g., acetaminophen, ibuprofen) - Apply external cooling methods as needed (cold packs or cool sponge bath) - Encourage fluid intake - Monitor for signs of dehydration Implementing Interventions When caring for a patient with an active infection, transmission-based precautions may be required based on the specific type of pathogen. Antibiotics and/or other antimicrobials are administered as prescribed, and the patient and family are instructed how to take prescribed antibiotics with measures to prevent antibiotic resistance (i.e., complete prescribed length of therapy even if they feel better in a few days). If cultures have been obtained, it is important to monitor and report new results to the provider to ensure the prescribed antibiotic therapy is appropriate based on susceptibility results. It is important to continually monitor patients with an existing infection for signs of SIRS/sepsis: - Carefully monitor vital signs. Immediately notify the provider for two or more of the following indicators that suggest SIRS: heart rate greater than 90 beats per minute, temperature greater than 38 degrees C or less than 36 degrees C, systolic blood pressure less than 90 mm Hg, respiratory rate greater than 20, or a white blood cell count greater than 12,000 or less than 4,000.Herdman, T., & Kamitsuru, S. (2017). NANDA international nursing diagnoses: Definitions & classification 2018-2020 (11th ed.). Thieme Publishers. pp. 382, 405. Anticipate new orders for a lactate level and blood cultures for early diagnosis of sepsis. - Monitor for signs of new decreased mental status, especially in older adults, that can indicate decreased oxygenation or tissue perfusion associated with sepsis and septic shock. - For patients presenting with early signs of shock, administer oxygen immediately to maintain oxygen saturation greater than 90%. Administer prescribed antibiotics within an hour after diagnosis for improved survival. Be aware that IV fluids and vasopressor medications may be required to treat shock.This work is a derivative of StatPearls by Chakraborty & Burns and is licensed under CC BY 4.0 Evaluation It is always important to evaluate the effectiveness of interventions used to prevent and treat infection. Evaluation helps the nurse determine whether the established outcomes have been met and if the planned interventions are still appropriate for the patient at the time of implementation. If outcomes are not met, interventions may need to be added or revised to help the patient meet their goals. 9.8 Putting It All Together Patient Scenario Mrs. Charles is a 74-year-old woman admitted to the medical surgical floor with pneumonia. She has a history of right sided hemiplegia (paralysis on one side of the body) and dysphagia (difficulty swallowing) as a result of a cerebral vascular accident three years ago. Upon assessment, the patient has a RR of 22, and rhonchi in her upper lobes. Her oxygenation saturation is 89% on room air, and she is utilizing accessory muscles during respiration. Applying the Nursing Process Assessment: The nurse notes that the patient demonstrates tachypnea, hypoxemia, and abnormal breath sounds. She has a history of hemiplegia and dysphagia. Based on the assessment information that has been gathered, the following nursing care plan is created for Mrs. Charles. Nursing Diagnosis: Ineffective Airway Clearance related to excessive mucus as evidenced by adventitious breath sounds and alteration in respiratory rate. Overall Goal: The patient will maintain patent airway at all times. SMART Expected Outcome: Mrs. Charles will effectively clear secretions throughout the hospitalization. Planning and Implementing Nursing Interventions: The nurse will assess the patient’s respiratory rate, rhythm, and depth of respiration. The nurse will assess and instruct the patient on the methods of appropriate cough and deep breathing. The nurse will auscultate lung fields to identify areas of worsening airflow. The nurse will elevate the patient’s head of bed and encourage hydration to thin secretions. The nurse will instruct the patient regarding proper deep breathing exercises and encourage assisted ambulation to mobilize secretions. Sample Documentation: Mrs. Charles has ineffective airway clearance as a result of aspiration pneumonia secondary to dysphagia. The patient has rhonchi in bilateral upper lobes, decreased oxygenation, and tachypnea. In order to enhance airway clearance and mobilize secretions, the patient has received instruction to maintain fluid intake, increase ambulation, and cough and deep breathe. The patient will maintain an elevated head of bed to encourage ease of respiration and will be assessed frequently for worsening respiratory status. Evaluation: During the patient’s hospitalization, she maintains a patent airway and effectively clears secretions resulting in improved respiratory effort and overall function. The SMART outcome was “met.” 9.9 Learning Activities Open Resources for Nursing (Open RN) Learning Activities (Answers to “Learning Activities” can be found in the “Answer Key” at the end of the book. Answers to interactive activity elements will be provided within the element as immediate feedback.) An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=1568#h5p-67 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=1568#h5p-25 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=1568#h5p-98 “Infection Case Study” by Susan Jepsen for Lansing Community College are licensed under CC BY 4.0 IX Glossary Open Resources for Nursing (Open RN) Acute, self-limiting infections: Infections that develop rapidly and generally last only 10-14 days. Colds, ear infections, and coughs are considered acute, self-limiting infections. Antibodies: Y proteins created by B cells that are specific to each pathogen and lock onto its surface and mark it for destruction by other immune cells. The five classes of antibodies are IgG, IgM, IgA, IgD, and IgE. Aseptic technique: The purposeful reduction of pathogens to prevent the transfer of microorganisms from one person or object to another during a medical procedure. For example, a nurse administering parenteral medication or performing urinary catheterization uses aseptic technique. When performed properly, aseptic technique prevents contamination and transfer of pathogens to the patient from caregiver hands, surfaces, and equipment during routine care or procedures. B cells: Immune cells that mature in the bone marrow. B cells make Y-shaped proteins called antibodies that are specific to each pathogen and lock onto its surface and mark it for destruction by other immune cells. Bacteremia: The presence of bacteria in blood. Chronic infections: Infections that may persist for months. Hepatitis and mononucleosis are examples of chronic infections. Cytokines: Plasma proteins that communicate with other body organs and cells in the body to respond to and initiate inflammation. Cytokine storm: A severe immune reaction in which the body releases too many cytokines into the blood too quickly. A cytokine storm can occur as a result of an infection, autoimmune condition, or other disease. Signs and symptoms include high fever, inflammation, severe fatigue, and nausea. A cytokine storm can be severe or life-threatening and lead to multiple organ failure.National Cancer Institute. (n.d.) NCI Dictionary of Cancer Terms. https://www.cancer.gov/publications/dictionaries/cancer-terms/def/cytokine-storm Disease: Infections can lead to disease that causes signs and symptoms resulting in a deviation from the normal structure or functioning of the host. Disinfection: Removal of organisms from inanimate objects and surfaces. However, disinfection does not typically destroy all spores and viruses. Exposure: An encounter with a potential pathogen. Hand hygiene: Cleaning the hands by either washing hands with soap and water or using hand sanitizer. Healthcare-Associated Infection (HAI): An infection that is contracted in a health care facility or under medical care. Incubation period: The period of a disease after the initial entry of the pathogen into the host but before symptoms develop. Infection: The invasion and growth of a microorganism within the body. Inflammation: A response triggered by a cascade of chemical mediators that occur when pathogens successfully breach the nonspecific physical defenses of the immune system or when an injury occurs. Invasion: The spread of a pathogen throughout local tissues or the body. Local infection: Infection confined to a small area of the body, typically near the portal of entry, and usually presents with signs of redness, warmth, swelling, warmth, and pain. Purulent drainage may be present and extensive tissue involvement can cause decreased function. Microbiome: Every human being carries their own individual suite of microorganisms in and on their body referred to as their microbiome. A person’s microbiome is acquired at birth and evolves over their lifetime. It is different across body sites and between individuals. Mode of transmission: The vehicle by which the organism is transferred such as physical contact, droplets, or airborne. The most common vehicles are a cough, sneeze, or on the hands. Nonspecific innate immunity: A system of defenses in the body that targets invading pathogens in a nonspecific manner that is present from the moment we are born. Nonspecific innate immunity includes physical defenses, chemical defenses, and cellular defenses. Normal flora: Microorganisms that live on our skin and in the nasopharynx and gastrointestinal tracts and don’t cause an infection unless the host becomes susceptible. Opportunistic pathogen: A pathogen that only causes disease in situations that compromise the host’s defenses, such as the body’s protective barriers, immune system, or normal microbiota. Individuals susceptible to opportunistic infections include the very young, the elderly, women who are pregnant, patients undergoing chemotherapy, people with immunodeficiencies (such as acquired immunodeficiency syndrome [AIDS]), patients who are recovering from surgery, and those who have had a breach of protective barriers (such as a severe wound or burn). Pathogen: Microorganisms that cause disease. Pathogenicity: The ability of a microorganism to cause disease. Peristalsis: A series of muscular contractions in the digestive tract that moves digested material and microbes through the intestine and excretes it in the feces. Personal Protective Equipment (PPE): Gloves, gowns, face shields, goggles, and masks used to prevent the spread of infection to and from patients and health care providers. Portal of entry: An anatomic site through which pathogens can pass into a host, such as mucous membranes, skin, respiratory, or digestive systems. Portal of exit: The method by which the organism leaves the reservoir as through secretions, blood, urine, breast milk, or feces. Primary pathogen: A pathogen that can cause disease in a host regardless of the host’s resident microbiota or immune system. Prodromal period: The disease stage after the incubation period when the pathogen continues to multiply and the host begins to experience general signs and symptoms of illness that result from activation of the immune system, such as fever, pain, soreness, swelling, or inflammation. Usually, such signs and symptoms are too general to indicate a particular disease. Reservoir: The place the organism grows such as a wound, blood, or food. Secondary infection: A localized pathogen that spreads to a secondary location. Sepsis: An existing infection that triggers an exaggerated inflammatory reaction called SIRS throughout the body. If left untreated, sepsis causes tissue damage and quickly spreads to multiple organs. It is a life-threatening medical emergency. Septicemia: Bacteria that are both present and multiplying in the blood. Septic shock: Severe sepsis that leads to a life-threatening decrease in blood pressure (systolic pressure <90 mm Hg), preventing cells and other organs from receiving enough oxygen and nutrients. It can cause multi-organ failure and death. Specific adaptive immunity: The immune response that is activated when the nonspecific innate immune response is insufficient to control an infection. There are two types of adaptive responses: the cell-mediated immune response, which is carried out by T cells, and the humoral immune response, which is controlled by activated B cells and antibodies. Standard precautions: The minimum infection prevention practices that apply to all patient care, regardless of suspected or confirmed infection status of the patient, in any setting where health care is delivered. Sterile technique: A process, also called surgical asepsis, used to eliminate every potential microorganism in and around a sterile field while also maintaining objects as free from microorganisms as possible. It is the standard of care for surgical procedures, invasive wound management, and central line care. Sterile technique requires a combination of meticulous hand washing, creating a sterile field, using long-lasting antimicrobial cleansing agents such as Betadine, donning sterile gloves, and using sterile devices and instruments. Sterilization: A process used to destroy all pathogens from inanimate objects, including spores and viruses. Susceptible host: The person whose body the organism has entered. Systemic infection: An infection that becomes disseminated throughout the body. Systemic Inflammatory Response Syndrome (SIRS): An exaggerated inflammatory response to a noxious stressor (including, but not limited to, infection and acute inflammation) that affects the entire body. T cells: Immune cells that mature in the thymus. T cells are categorized into three classes: helper T cells, regulatory T cells, and cytotoxic T cells. Helper T cells stimulate B cells to make antibodies and help killer cells develop. T cells also use cytokines as messenger molecules to send chemical instructions to the rest of the immune system to ramp up its response. Transmission-based precautions: Precautions used for patients with documented or suspected infection, or colonization, of highly-transmissible pathogens, such as C. difficile (C-diff), Methicillin-resistant Staphylococcus aureus (MRSA), Vancomycin-resistant enterococci (VRE), Respiratory Syncytial Virus (RSV), measles, and tuberculosis (TB). Three categories of transmission-based precautions are contact precautions, droplet precautions, and airborne precautions. Virulence: The degree to which a microorganism is likely to become a disease. Integumentary X 10.1 Integumentary Introduction Open Resources for Nursing (Open RN) Learning Objectives - Identify the patients at risk for impaired skin integrity - Identify factors related to alterations in the integumentary system across the life span - Assess a patient’s skin integrity - Note normal from abnormal findings - Assess the characteristics of the wound - Apply correct terminology in the description of wounds - Adapt care based on integumentary assessment data gathered - Identify evidence-based practices The integumentary system includes skin, hair, and nails. The skin is the largest organ of the body and has many purposes. Our skin keeps us warm and contains nerve endings that control the ability to feel the sensations of hot, cold, pain, and pressure. Our skin also keeps harmful things out of the body, such as dirt, bacteria, and viruses, and keeps helpful things in like moisture. Maintaining intact skin is important to prevent infection and maintain health. This chapter will review the anatomy and physiology of the integumentary system, factors that affect healthy skin and healing, and interventions that nurses perform to repair and protect this vital organ. 10.2 Integumentary Basic Concepts Open Resources for Nursing (Open RN) Skin Skin is made up of three layers: epidermis, dermis, and hypodermis. See Figure 10.1“501 Structure of the skin.jpg” by OpenStax is licensed under CC BY 3.0. Access for free at https://openstax.org/books/anatomy-and-physiology/pages/5-1-layers-of-the-skin for an illustration of skin layers. The epidermis is the thin, topmost layer of the skin. It contains sweat gland duct openings and the visible part of hair known as the hair shaft. Underneath the epidermis lies the dermis where many essential components of skin function are located. The dermis contains hair follicles (the roots of hair shafts), sebaceous oil glands, blood vessels, endocrine sweat glands, and nerve endings. The bottommost layer of skin is the hypodermis (also referred to as the subcutaneous layer). It mostly consists of adipose tissue (fat), along with some blood vessels and nerve endings. Beneath the hypodermis layer lies bone, muscle, ligaments, and tendons. There are several common skin disorders that a nurse may find when assessing a patient’s skin. Hair Hair is a filament that grows from a hair follicle in the dermis of the skin. See Figure 10.2“506 Hair.jpg” by OpenStax is licensed under CC BY 3.0. Access for free at https://openstax.org/books/anatomy-and-physiology/pages/5-2-accessory-structures-of-the-skin. for an illustration of a hair follicle. It consists mainly of tightly packed, keratin-filled cells called keratinocytes. The human body is covered with hair follicles except for the mucous membranes, lips, palms of the hands, and soles of the feet. The part of the hair that is located within the follicle is called the hair root, the only living part of the hair. The part of the hair that is visible above the surface of the skin is the hair shaft. The shaft of the hair has no biochemical activity and is considered dead. Functions of Hair The functions of head hair are to provide insulation to retain heat and to protect the skin from damage by UV light. The function of hair in other locations on the body is debated. One idea is that body hair helps to keep us warm in cold weather. When the body is cold, the arrector pili muscles contract, causing hairs to stand up and trapping a layer of warm air above the epidermis. However, this action is more effective in mammals that have thick hair than it is in relatively hairless human beings. Human hair has an important sensory function as well. Sensory receptors in the hair follicles can sense when the hair moves, whether it is because of a breeze or the touch of a physical object. Some hairs, such as the eyelashes, are especially sensitive to the presence of potentially harmful matter. The eyebrows protect the eyes from dirt, sweat, and rain. In addition, the eyebrows play a key role in nonverbal communication by expressing emotions such as sadness, anger, surprise, and excitement.This work is a derivative of Human Biology by Wakim and Grewal and is licensed under CC-BY-NC 4.0 Nails Nails are accessory organs of the skin. They are made of sheets of dead keratinocytes and are found on the distal ends of the fingers and toes. The keratin in nails makes them hard but flexible. Nails serve a number of purposes, including protecting the fingers, enhancing sensations, and acting like tools. A nail has three main parts: root, plate, and free margin. Other structures around or under the nail include the nail bed, cuticle, and nail fold. See Figure 10.3 for an illustration of the structure of a nail.“Blausen_0406_FingerNailAnatomy.png” by BruceBlaus is licensed under CC BY 3.0,This work is a derivative of Human Biology by Wakim and Grewal and is licensed under CC-BY-NC 4.0 The top diagram in this figure shows the external, visible part of the nail and the cuticle. The bottom diagram shows internal structures in a cross-section of the nail and nail bed. Impaired Skin and Tissue Integrity Skin integrity is a medical term that refers to skin health. Impaired skin integrity is a NANDA-I nursing diagnosis defined as, “Altered epidermis/or dermis.”Herdman, T., & Kamitsuru, S. (2017). NANDA international nursing diagnoses: Definitions & classification 2018-2020 (11th ed.). Thieme Publishers. pp. 404, 406, 407, 412, 413. However, when deeper layers of the skin or integumentary structures are damaged, it is referred to as impaired tissue integrity. The NANDA-I definition of impaired tissue integrity is, “Damage to the mucous membrane, cornea, integumentary system, muscular fascia, muscle, tendon, bone, cartilage, joint capsule, and/or ligament.”Herdman, T., & Kamitsuru, S. (2017). NANDA international nursing diagnoses: Definitions & classification 2018-2020 (11th ed.). Thieme Publishers. pp. 404, 406, 407, 412, 413. Risk Factors Affecting Skin Health and Wound Healing There are several risk factors that place a patient at increased risk for altered skin health and delayed wound healing. Risk factors include impaired circulation and oxygenation, impaired immune function, diabetes, inadequate nutrition, obesity, exposure to moisture, smoking, and age. Each of these risk factors is discussed in more detail in the following subsections. Impaired Circulation and Oxygenation Skin, like every other organ in the body, depends on good blood perfusion to keep it healthy and functioning correctly. Cardiovascular circulation delivers important oxygen, nutrients, infection-fighting cells, and clotting factors to tissues. These elements are needed by skin, tissues, and nerves to properly grow, function, and repair damage. Without good cardiovascular circulation, skin becomes damaged. Damage can occur from poor blood perfusion from the arteries, as well as from poor return of blood through the veins to the heart. Common medical conditions that decrease cardiovascular circulation include cardiac disease, diabetes, and peripheral vascular disease (PVD). PVD includes two medical conditions called arterial insufficiency and venous insufficiency. Arterial Insufficiency Arterial insufficiency refers to a lack of adequately oxygenated blood movement in arteries to specific tissues. Arterial insufficiency can be a sudden, acute lack of oxygenated blood, such as when a blood clot in an artery blocks blood flow to a specific area. Arterial insufficiency can also be a chronic condition caused by peripheral vascular disease (PVD). As a person’s arteries become blocked with plaque due to atherosclerosis, there is decreased blood flow to the tissues. Signs of arterial insufficiency are cool skin temperature, pale skin color, pain that increases with exercise, and possible arterial ulcers. When oxygenated blood flow to tissues becomes inadequate, the tissue dies. This is called necrosis. Tissue death causes the skin and tissue to become necrotic (black). Necrotic tissue does not heal, so surgical debridement or amputation of the extremity becomes necessary for healing. See Figure 10.4“JCCD147F1.gif” and “Infective-necrosis-of-second-toe_fig5_40484391” by unknown are licensed under CC BY 4.0 and CC BY-NC 4.0. Access for free at https://www.sciforschenonline.org/journals/clinical-cosmetic-dermatology/JCCD147.php and https://www.researchgate.net/figure/nfective-necrosis-of-second-toe_fig5_40484391 for images of an arterial insufficiency ulcer and necrotic toes. Venous Insufficiency Venous insufficiency occurs when the cardiovascular system cannot adequately return blood and fluid from the extremities to the heart. Venous insufficiency can cause stasis dermatitis when blood pools in the lower legs and leaks out into the skin and other tissues. Signs of venous insufficiency are edema, a brownish-leathery appearance to skin in the lower extremities, and venous ulcers that weep fluid.Blackburn, L., Acree, K., Bartley, J., DiGiannantoni, E., Renner, E., & Sinnott, L. T. (2020). Microbial growth on the nails of direct patient care nurses wearing nail polish. Nursing Oncology Forum, 47(2), 155-164. https://doi.org/10.1188/20.onf.155-164 See Figure 10.5”3056fig1_opt.jpeg” by unknown is licensed under CC BY-NC 4.0. Access for free at https://www.medicaljournals.se/acta/content/html/10.2340/00015555-0692 for an image of stasis dermatitis. Impaired Immune Function Skin contributes to the body’s immune function and is also affected by the immune system. Intact skin provides an excellent first line of defense against foreign objects entering the body. This is why it is essential to keep skin intact. If skin does break down, the next line of defense is a strong immune system that attacks harmful invading organisms. However, if the immune system is not working well, the body is much more susceptible to infections. This is why maintaining intact skin, especially in the presence of an impaired immune system, is imperative to decrease the risk of infections. Stress can cause an impaired immune response that results in delayed wound healing.Butcher, H., Bulechek, G., Dochterman, J., & Wagner, C. (2018). Nursing interventions classification (NIC). Elsevier. pp. 348-349, 417-419. Being hospitalized or undergoing surgery triggers the stress response in many patients. Medications, such as corticosteroids, also affect a patient’s immune function and can impair wound healing.Butcher, H., Bulechek, G., Dochterman, J., & Wagner, C. (2018). Nursing interventions classification (NIC). Elsevier. pp. 348-349, 417-419. When assessing a chronic wound that is not healing as expected, it is important to consider the potential effects of stress and medications. Diabetes Diabetes can cause wounds to develop, as well as cause delayed wound healing. Nurses provide vital patient education to patients with diabetes to help them effectively manage the disease and prevent complications. Read more about diabetes in the “Antidiabetics” section of the “Endocrine” chapter in Open RN Nursing Pharmacology. Inadequate Nutrition A healthy diet is essential for maintaining healthy skin, as well as maintaining an appropriate weight. Nutrients that are particularly important for skin health include protein; vitamins A, C, D, and E; and minerals such as selenium, copper, and zinc.Park, K. (2015). Role of micronutrients in skin health and function. Biomolecules & Therapeutics, 23(3), 207–217. https://doi.org/10.4062/biomolther.2015.003 Nutritional deficiencies can have a profound impact on wound healing and must be addressed for chronic wounds to heal. Protein is one of the most important nutritional factors affecting wound healing. For example, in patients with pressure injuries, 30 to 35 kcal/kg of calorie intake with 1.25 to 1.5g/kg of protein and micronutrients supplementation are recommended daily.Cox, J. (2019). Wound care 101. Nursing, 49(10), 32-39. https://doi.org/10.1097/01.nurse.0000580632.58318.08 In addition, vitamin C and zinc have many roles in wound healing. It is important to collaborate with a dietician to identify and manage nutritional deficiencies when a patient is experiencing poor wound healing.Guo, S., & Dipietro, L. A. (2010). Factors affecting wound healing. Journal of Dental Research, 89(3), 219–229. https://doi.org/10.1177/0022034509359125 Obesity In the same way a balanced diet is vital for healthy skin, a healthy weight is also imperative. Obese individuals are at increased risk for fungal and yeast infections in skin folds caused by increased moisture and friction. See Figure 10.6“Tinea cruris.jpg” by Robertgascoin is licensed under CC BY-SA 3.0 for an image of a fungal infection in the groin.Rosen, T. (2011). Inframammary candida intertrigo. UpToDate. https://somepomed.org/articulos/contents/mobipreview.htm?0/29/474 Symptoms of yeast and fungal infection include redness and scaliness of the skin associated with itching. Obese patients also are at higher risk for wound complications due to a decreased supply of oxygenated blood flow to adipose tissue. Potential complications include infection, dehiscence (separation of the edges of a surgical wound), hematoma formation, pressure injuries, and venous ulcers.Guo, S., & Dipietro, L. A. (2010). Factors affecting wound healing. Journal of Dental Research, 89(3), 219–229. https://doi.org/10.1177/0022034509359125 Evisceration is a rare but severe complication when an abdominal surgical incision separates and the abdominal organs protrude or come out of the incision. Nurses can educate patients about making healthy lifestyle choices to reduce obesity and the risk of dehiscence. See Figure 10.7“Bogota bag.png” by Suarez-Grau, J. M., Guadalajara Jurado, J. F., Gómez Menchero, J., & Bellido Luque, J. A. is licensed under CC BY 4.0 for an image of a dehiscence in an abdominal surgical wound of an obese patient. Exposure to Moisture Healthy skin needs good moisture balance. If too much moisture (i.e., sweat, urine, or water) is left on the skin for extended periods of time, the skin will become soggy, wrinkly, and turn whiter than usual and is called maceration. See Figure 10.8“Trench_foot.jpg” by Mehmet Karatay is licensed under CC BY-SA 3.0 for an image of maceration. If healthy skin is exposed to moisture for an extended period of time, such as when a moist wound dressing is incorrectly applied on healthy skin, the skin will break down. This type of skin breakdown is called excoriation. Excoriation refers to redness and removal of the topmost surface of the skin. See Figure 10.9“Dermatomyositis15.jpg” by Elizabeth M. Dugan, Adam M. Huber, Frederick W. Miller, and Lisa G. Rider is licensed under CC BY-SA 3.0 for an image of excoriation. The opposite occurs when skin lacks proper moisture. Skin becomes flaky, itchy, and cracked when it becomes too dry. Conditions such as decreased moisture in the air during cold winter months or bathing in hot water can worsen skin dryness. Dry skin, especially when accompanied with cracking, breaks the protective barrier and increases the risk of infection. It is important for nurses to apply emollient cream to patients’ areas of dry skin to maintain the protective skin barrier. Smoking Smoking impacts the inflammatory phase of the wound healing process, which can result in poor wound healing and an increased risk of infection.Guo, S., & Dipietro, L. A. (2010). Factors affecting wound healing. Journal of Dental Research, 89(3), 219–229. https://doi.org/10.1177/0022034509359125 Patients who smoke should be encouraged to stop smoking. Age Older adults have thin, less elastic skin that is at increased risk for injury. They also have an altered inflammatory response that can impair wound healing. Nurses can educate older patients about the importance of exercise for skin health and improved wound healing as appropriate.Guo, S., & Dipietro, L. A. (2010). Factors affecting wound healing. Journal of Dental Research, 89(3), 219–229. https://doi.org/10.1177/0022034509359125 10.3 Wounds Open Resources for Nursing (Open RN) Phases of Wound Healing When skin is injured, there are four phases of wound healing that take place: hemostasis, inflammatory, proliferative, and maturation. See Figure 10.10“417 Tissue Repair.jpg” by OpenStax is licensed under CC BY 3.0. Access for free at https://openstax.org/books/anatomy-and-physiology/pages/1-introduction for an illustration of wound healing demonstrating hemostasis/inflammation, proliferation, and maturation. To illustrate the phases of wound healing, imagine that you accidentally cut your finger with a knife as you were slicing an apple for a snack. Immediately after the injury occurs, blood vessels constrict and clotting factors are activated. This is referred to as the hemostasis phase. Clotting factors are released to form clots and to stop the bleeding. Platelets release growth factors that alert various cells to start the repair process at the wound location. The hemostasis phase lasts up to 60 minutes, depending on the severity of the injury.This work is a derivative of Clinical Procedures for Safer Patient Care by British Columbia Institute of Technology and licensed under CC BY 4.0,This work is a derivative of StatPearls by Grubbs & Manna and is licensed under CC BY 4.0 After the hemostasis phase, the inflammatory phase begins. Vasodilation occurs so that white blood cells in the bloodstream can move to the location of the wound and start cleaning the wound bed. The inflammatory process appears as edema (swelling), erythema (redness), and exudate. Exudate is fluid that oozes out of a wound and is commonly called pus or drainage.This work is a derivative of Clinical Procedures for Safer Patient Care by British Columbia Institute of Technology and licensed under CC BY 4.0,This work is a derivative of StatPearls by Grubbs & Manna and is licensed under CC BY 4.0 The proliferative phase of wound healing begins within a few days after the injury and includes four important processes: epithelialization, angiogenesis, collagen formation, and contraction. Epithelialization refers to the development of new epidermis and granulation tissue. Granulation tissue is new connective tissue with new, fragile, thin-walled capillaries. Collagen is also formed to provide strength and integrity to the wound. At the end of the proliferation phase, the wound begins to contract in size.This work is a derivative of Clinical Procedures for Safer Patient Care by British Columbia Institute of Technology and licensed under CC BY 4.0,This work is a derivative of StatPearls by Grubbs & Manna and is licensed under CC BY 4.0 Capillaries begin to develop within the wound 24 hours after injury during a process called angiogenesis. These capillaries bring more oxygen and nutrients to the wound for healing. When performing dressing changes, it is essential for the nurse to protect this granulation tissue and the associated new capillaries. Healthy granulation tissue appears pink due to the new capillary formation. It is moist, painless to the touch, and may appear “bumpy.” Conversely, unhealthy granulation tissue is dark red and painful. It bleeds easily with minimal contact and may be covered by shiny white or yellow fibrous tissue, referred to as biofilm, that must be removed because it impedes healing. Unhealthy granulation tissue is often caused by an infection, so wound cultures should be obtained when infection is suspected.McKay, M. (1990). The dermatologic history. In Walker, H. K., Hall, W. D., Hurst, J. W. (Eds.), Clinical methods: The history, physical, and laboratory examinations (3rd ed.). https://www.ncbi.nlm.nih.gov/books/NBK207/ During the maturation phase, collagen continues to be created to strengthen the wound. Collagen contributes strength to the wound to prevent it from reopening. A wound typically heals within 4-5 weeks and often leaves behind a scar. The scar tissue is initially firm, red, and slightly raised from the excess collagen deposition. Over time, the scar begins to soften, flatten, and become pale in about nine months.This work is a derivative of Clinical Procedures for Safer Patient Care by British Columbia Institute of Technology and licensed under CC BY 4.0,This work is a derivative of StatPearls by Grubbs & Manna and is licensed under CC BY 4.0 Types of Wound Healing There are three types of wound healing: primary intention, secondary intention, and tertiary intention. Healing by primary intention means that the wound is sutured, stapled, glued, or otherwise closed so the wound heals beneath the closure. This type of healing occurs with clean-edged lacerations or surgical incisions, and the closed edges are referred to as approximated. See Figure 10.11“Ventriculoperitoneal shunt – surgical wound healing – belly – day 12.jpg” by Hansmuller is licensed under CC BY-SA 4.0 for an image of a surgical wound healing by primary intention with approximated edges. Secondary intention occurs when the edges of a wound cannot be approximated (brought together), so the wound heals by filling in from the bottom up with the production of granulation tissue. Examples of common wounds that heal by secondary intention are pressure injuries and skin tears. Wounds that heal by secondary infection are at higher risk for infection and must be protected from contamination. See Figure 10.12“Atrophied skin.png” by sansea2 is licensed under CC BY-SA 3.0 for an image of a wound healing by secondary intention. Tertiary intention refers to the healing of a wound that has had to remain open or has been reopened, often due to severe infection. The wound is typically closed at a later date when infection has resolved. Wounds that heal by secondary and tertiary intention have delayed healing times and increased scar tissue. Types of Wounds There are many common types of wounds that nurses care for, such as skin tears, venous ulcers, arterial ulcers, diabetic ulcers, and pressure injuries. Wound Care Wound care includes assessing and cleansing wounds, performing dressing changes, and implementing interventions to promote wound healing. Assessing wounds and implementing interventions to promote wound healing are further discussed in the “Applying the Nursing Process” section later in this chapter. 10.4 Pressure Injuries Open Resources for Nursing (Open RN) The remainder of this chapter will focus on applying the nursing process to a specific type of wound called a pressure injury. Pressure injuries are defined as, “Localized damage to the skin or underlying soft tissue, usually over a bony prominence, as a result of intense and prolonged pressure in combination with shear.” (Note that the 2016 NPUAP Pressure Injury Staging System now uses the term “pressure injury” instead of the historic term “pressure ulcer” because a pressure injury can occur without an ulcer present.) Pressure injuries commonly occur on the sacrum, heels, ischia, and coccyx and form when the skin layer of tissue gets caught between an external hard surface, such as a bed or chair, and the internal hard surface of a bone. Shear occurs when tissue layers move over the top of each other, causing blood vessels to stretch and break as they pass through the subcutaneous tissue. For example, when a patient slides down in bed, the outer layer of skin remains immobile because it remains attached to the sheets due to friction. However, the deeper layer of tissue (attached to bone) moves as the patient slides down. This opposing movement of the outer layer of skin and the underlying tissues causes the capillaries to stretch and tear, which then causes decreased blood flow and oxygenation of the surrounding tissues resulting in a pressure injury.Edsberg, L. E., Black, J. M., Goldberg, M., McNichol, L., Moore, L., & Sieggreen, M. (2016). Revised national pressure ulcer advisory panel pressure injury staging system: Revised pressure injury staging system. Journal of Wound, Ostomy, and Continence Nursing: Official Publication of The Wound, Ostomy and Continence Nurses Society, 43(6), 585–597. https://doi.org/10.1097/WON.0000000000000281 Friction refers to rubbing the skin against a hard object, such as the bed or the arm of a wheelchair. This rubbing causes heat, which can remove the top layer of skin and often results in skin damage. See Figure 10.13“Shear Force” and “Shear Force Closeup” by Meredith Pomietlo at Chippewa Valley Technical College are licensed under CC BY 4.0 for an illustration of shear and friction forces in the development of pressure injuries. Hospital-acquired or worsening pressure injuries during hospitalization are considered “never events” meaning they are a serious, preventable medical errors that should never occur and require reporting to The Joint Commission. Additionally, the Centers for Medicare and Medicaid Services (CMS) and many private insurers will no longer pay for additional costs associated with “never events.”Agency for Healthcare Research and Quality. (2019, September). Never events. psnet.ahrq.gov/primer/never-events,AMN Healthcare Education Services. (2020). Pressure injury: Never event. rn.com/clinical-insight-pressure-injury/ Pressure injuries can be prevented with diligent assessment and nursing interventions. Staging When assessed, pressure injuries are staged from 1 through 4 based on the extent of tissue damage. For example, Stage 1 pressure injuries have the least amount of tissue damage as evidenced by reddened, intact skin, whereas Stage 4 pressure injuries have the greatest amount of damage with deep, open ulcers affecting underlying tissue, muscle, ligaments, or tendons. See Figure 10.14“Wound stage.jpg” by Babagolzadeh is licensed under CC BY-SA 3.0 for images of four stages of pressure injuries.Edsberg, L. E., Black, J. M., Goldberg, M., McNichol, L., Moore, L., & Sieggreen, M. (2016). Revised national pressure ulcer advisory panel pressure injury staging system: Revised pressure injury staging system. Journal of Wound, Ostomy, and Continence Nursing: Official Publication of The Wound, Ostomy and Continence Nurses Society, 43(6), 585–597. https://doi.org/10.1097/WON.0000000000000281 Each stage is further described in the following subsections. Stage 1 Pressure Injuries Stage 1 pressure injuries are intact skin with a localized area of nonblanchable erythema where prolonged pressure has occurred. Nonblanchable erythema is a medical term used to describe an area of reddened skin that does not turn white when pressed. See Figure 10.15“Stage1-Darkly_Pigmented” and “Skin_01__healthy_skin_-_l_pigmen.jpg” provided by National Pressure Injury Advisory Panel are used with permission for educational purposes. Access for free at https://npiap.com/page/PressureInjuryStages for an illustration of a Stage 1 pressure injury. Stage 2 Pressure Injuries Stage 2 pressure injuries are partial-thickness loss of skin with exposed dermis. The wound bed is viable and may appear like an intact or ruptured blister.Edsberg, L. E., Black, J. M., Goldberg, M., McNichol, L., Moore, L., & Sieggreen, M. (2016). Revised national pressure ulcer advisory panel pressure injury staging system: Revised pressure injury staging system. Journal of Wound, Ostomy, and Continence Nursing: Official Publication of The Wound, Ostomy and Continence Nurses Society, 43(6), 585–597. https://doi.org/10.1097/WON.0000000000000281 See Figure 10.16“20201202_114031_31850.jpg” and “stage_2_april_2020.jpg” provided by National Pressure Injury Advisory Panel are used with permission for educational purposes. Access for free at https://npiap.com/page/PressureInjuryStages. for an illustration of a Stage 2 pressure injury. Stage 3 Pressure Injuries Stage 3 pressure injuries are full-thickness tissue loss in which fat is visible, but cartilage, tendon, ligament, muscle, and bone are not exposed. The depth of tissue damage varies by anatomical location. See Figure 10.17“20201202_114132_23541.jpg” and ”stage_3_april_2020.jpg” provided by National Pressure Injury Advisory Panel are used with permission for educational purposes. Access for free at https://npiap.com/page/PressureInjuryStages for an illustration of a Stage 3 pressure injury. Undermining and tunneling may occur in Stage 3 and 4 pressure injuries. Undermining occurs when the tissue under the wound edge becomes eroded, resulting in a pocket beneath the skin. Tunneling refers to passageways underneath the skin surface that extend from a wound and can take twists and turns. Slough and eschar may also be present in Stage 3 and 4 pressure injuries. Slough is inflammatory exudate that is usually light yellow, soft, and moist. Eschar is dark brown/black, dry, thick, and leathery dead tissue. If slough or eschar obscures the wound so that tissue loss cannot be assessed, the pressure injury is referred to as unstageable.Davis, C. P. Normal flora. (1996). In S. Baron (Ed.), Medical Microbiology (4th ed.). University of Texas Medical Branch at Galveston. https://www.ncbi.nlm.nih.gov/books/NBK7617/ In most wounds, slough and eschar must be removed by debridement for healing to occur. Stage 4 Pressure Injuries Stage 4 pressure injuries are full-thickness tissue loss, like in Stage 3 pressure injuries, but also have exposed cartilage, tendon, ligament, muscle, or bone. Osteomyelitis (bone infection) may also be present.Edsberg, L. E., Black, J. M., Goldberg, M., McNichol, L., Moore, L., & Sieggreen, M. (2016). Revised national pressure ulcer advisory panel pressure injury staging system: Revised pressure injury staging system. Journal of Wound, Ostomy, and Continence Nursing: Official Publication of The Wound, Ostomy and Continence Nurses Society, 43(6), 585–597. https://doi.org/10.1097/WON.0000000000000281 See Figure 10.18“20201202_114459_31029.jpg” and “stage_4_april_2020.jpg” provided by National Pressure Injury Advisory Panel are used with permission for educational purposes. Access for free at https://npiap.com/page/PressureInjuryStages for an illustration of a Stage 4 pressure injury. Unstageable Pressure Injuries Unstageable pressure injuries are full-thickness skin and tissue loss in which the extent of tissue damage within the ulcer cannot be confirmed because it is obscured by slough or eschar. If slough or eschar were to be removed, a Stage 3 or Stage 4 pressure injury would likely be revealed. However, dry and adherent eschar on the heel or ischemic limb is not typically removed.A.D.A.M. Medical Encyclopedia [Internet]. Atlanta (GA): A.D.A.M., Inc.; c1997-2020. Stasis dermatitis and ulcers; [updated 2020, Dec 3; reviewed 2018, Oct 14; cited 2020, Dec 10]. https://medlineplus.gov/ency/article/000834.htm See Figure 10.19“Unstageable- Darkly Pigmented_Skin.jpg” and “unstageable-halfslough__1_.jpg” provided by National Pressure Injury Advisory Panel are used with permission for educational purposes. Access for free at https://npiap.com/page/PressureInjuryStages for an illustration of an unstageable pressure ulcer due to the presence of eschar (on the left side of the wound) and slough (on the right side of the wound). Deep Tissue Pressure Injuries Deep tissue pressure injuries consist of persistent nonblanchable and deep red, maroon, or purple discoloration of an area. These discolorations typically reveal a dark wound bed or blood-filled blister. Be aware that the discoloration may appear differently in darkly pigmented skin. Deep tissue injury results from intense and/or prolonged pressure, as well as shear forces at the bone-muscle interface. The wound may evolve rapidly to reveal the actual extent of tissue injury, or it may resolve without tissue loss.Edsberg, L. E., Black, J. M., Goldberg, M., McNichol, L., Moore, L., & Sieggreen, M. (2016). Revised national pressure ulcer advisory panel pressure injury staging system: Revised pressure injury staging system. Journal of Wound, Ostomy, and Continence Nursing: Official Publication of The Wound, Ostomy and Continence Nurses Society, 43(6), 585–597. https://doi.org/10.1097/WON.0000000000000281,“DTPI-Darkly Pigmented Skin” and “deep_tissue_pressure_injury_.jpg” provided by National Pressure Injury Advisory Panel are used with permission for educational purposes. Access for free at https://npiap.com/page/PressureInjuryStages See Figure 10.20 for an illustration of a deep tissue injury. Video Review of Assessing Pressure InjuriesRegisteredNurseRN. (2018, March 7). Pressure ulcers (injuries) stages, prevention, assessment \| Stage 1, 2, 3, 4 unstageable NCLEX. [Video]. YouTube. All rights reserved. Video used with permission. https://youtu.be/MDtPik1UE6k 10.5 Braden Scale Open Resources for Nursing (Open RN) Several factors place a patient at risk for developing a pressure injury, in addition to shear and friction. These factors include decreased sensory perception, increased moisture, decreased activity, impaired mobility, and inadequate nutrition. The Braden Scale is a standardized, evidence-based assessment tool commonly used in health care to assess and document a patient’s risk for developing pressure injuries. See Figure 10.21This work is derivative of the “Braden Scale” by Prevention Plus. Used under Fair Use. Access for free at https://www.in.gov/core/results.html?collection=global-collection&profile=_default&query=braden+scale for an image of a Braden Scale. Risk factors are rated on a scale from 1 to 4, with 1 being “completely limited” and 4 being “no impairment.” The scores from the six categories are added, and the total score indicates a patient’s risk for developing a pressure injury based on these ranges: - Mild risk: 15-18 - Moderate risk: 13-14 - High risk: 10-12 - Severe risk: less than 9 How to Score the Braden Scale Each risk factor on the Braden Scale is rated from 1 to 4 based on the patient’s assessment findings. When using the Braden Scale, start with the first category and review each description listed across the row for each of the ratings from 1 to 4, and choose the one that best describes the patient’s current status. Continue this process for all rows. Add all six numbers to determine a total score, and then use the total score to determine if the patient is at mild, moderate, high, or severe risk for developing a pressure injury. The lower the score, the higher the risk of developing a pressure injury. Additionally, customized nursing interventions are implemented based on the rating in each category. The higher the score, the more aggressive actions are taken to prevent or heal a pressure injury. Descriptions of the ratings from 1-4 for each risk factor, along with targeted interventions for each rating, are further described in the following subsections. Sensory Perception The sensory perception risk factor is defined as the ability to respond meaningfully to pressure-related discomfort. If a patient is unable to feel pressure-related discomfort and respond to it appropriately by moving or reporting pain, they are at high risk of developing a pressure injury. This risk category describes two different issues that affect sensory perception. The first description refers to the patient’s level of consciousness, and the second description refers to the patient’s ability to feel cutaneous sensation. See Table 10.5a for a description of each level of risk from 1-4 with associated interventions for each level.Agency for Healthcare Research and Quality. (2014). Preventing pressure ulcers in hospitals. https://www.ahrq.gov/patient-safety/settings/hospital/resource/pressureulcer/tool/pu7b.htm Table 10.5a Descriptions and Interventions by Level of Risk for Sensory Perception \| Assessment Category \| Rating Description \| Interventions \| \|---\|---\|---\| \| Sensory Perception \| 4–No Impairment Responds to verbal commands. Has no sensory deficit that would limit ability to feel or voice pain or discomfort. \| \| \| Sensory Perception \| 3–Slightly Limited Responds to verbal commands, but cannot always communicate discomfort or the need to be turned. OR Has some sensory impairment that limits ability to feel pain or discomfort in 1 or 2 extremities. \| \| \| Sensory Perception \| 2–Very Limited Responds only to painful stimuli. Cannot communicate discomfort except by moaning or restlessness. OR Has a sensory impairment that limits the ability to feel pain or discomfort over half of the body. \| All interventions mentioned in 3–Slightly Limited plus: \| \| Sensory Perception \| 1–Completely Limited Unresponsive (does not moan, flinch, or grasp) to painful stimuli, due to diminished level of consciousness or sedation. OR Limited ability to feel pain over most of the body. \| All interventions mentioned in 2–Very Limited plus: \| Moisture The moisture risk factor is defined as the degree to which skin is exposed to moisture. Prolonged exposure to moisture increases the probability of skin breakdown. Moisture can come from several sources, such as perspiration, urine incontinence, stool incontinence, or wound drainage. Frequent surveillance, removal of wet or soiled linens, and use of protective skin barriers greatly reduce this risk factor. See Table 10.5b for specific interventions for each level of risk.Agency for Healthcare Research and Quality. (2014). Preventing pressure ulcers in hospitals. https://www.ahrq.gov/patient-safety/settings/hospital/resource/pressureulcer/tool/pu7b.htm Table 10.5b Interventions by Level of Risk for Moisture \| Rating Description \| Interventions \| \| \|---\|---\|---\| \| Moisture \| 4–Rarely Moist Skin is usually dry; linen only requires changing at routine intervals. \| \| \| Moisture \| 3–Occasionally Moist Skin is occasionally moist, requiring an extra linen change approximately once per day. \| All interventions mentioned in 4–Rarely Moist plus: \| \| Moisture \| 2–Often Moist Skin is often but not always moist. Linen must be changed at least once per shift. \| All interventions mentioned in 3–Occasionally Moist plus: \| \| Moisture \| 1–Constantly Moist Skin is kept moist almost constantly by perspiration, urine, etc. Dampness is detected every time the patient is moved or turned. \| All interventions mentioned in 2–Often Moist plus: \| Activity The activity risk factor is defined as the degree of physical activity. For example, walking or moving from a bed to a chair reduces a patient’s risk of developing a pressure injury by redistributing pressure points and increasing blood and oxygen flow to areas at risk. Level of activity is defined by how frequently the patient is able to get out of bed, move into a chair, or ambulate with or without help. See Table 10.5c for a description of each level of risk from 1-4 with associated interventions for each.Agency for Healthcare Research and Quality. (2014). Preventing pressure ulcers in hospitals. https://www.ahrq.gov/patient-safety/settings/hospital/resource/pressureulcer/tool/pu7b.htm Table 10.5c Descriptions and Interventions by Level of Risk for ActivityAgency for Healthcare Research and Quality. (2014). Preventing pressure ulcers in hospitals. https://www.ahrq.gov/patient-safety/settings/hospital/resource/pressureulcer/tool/pu7b.htm \| Assessment Category \| Rating Description \| Interventions \| \|---\|---\|---\| \| Activity \| 4–Walks Frequently Walks outside the room at least twice a day and inside the room at least once every two hours during waking hours. \| \| \| Activity \| 3–Walks Occasionally Walks occasionally during the day, but for very short distances, with or without assistance. Spends the majority of each shift in bed or chair. \| \| \| Activity \| 2–Chair fast Ability to walk is severely limited or nonexistent. Cannot bear their own weight and/or must be assisted into chair or wheelchair. \| \| \| Activity \| 1–Bedfast Confined to bed. \| \| Mobility The mobility risk factor is defined as the patient’s ability to change or control their body position. For example, healthy people frequently change body position by rolling over in bed, shifting weight in a chair after sitting too long, or by moving their extremities. However, tissue damage will occur if a patient is unable to reposition on their own power unless caregivers frequently change their position. See Table 10.5d for interventions for each level of risk from 1-4.Agency for Healthcare Research and Quality. (2014). Preventing pressure ulcers in hospitals. https://www.ahrq.gov/patient-safety/settings/hospital/resource/pressureulcer/tool/pu7b.htm Table 10.5d Interventions by Level of Risk for MobilityAgency for Healthcare Research and Quality. (2014). Preventing pressure ulcers in hospitals. https://www.ahrq.gov/patient-safety/settings/hospital/resource/pressureulcer/tool/pu7b.htm \| Assessment Category \| Rating Description \| Interventions \| \|---\|---\|---\| \| Mobility \| 4–No Limitations Makes major and frequent changes in position without assistance. \| \| \| Mobility \| 3–Slightly Limited Makes frequent though slight changes in body or extremity position independently. \| \| \| Mobility \| 2–Very Limited Makes occasional slight changes in body or extremity position but unable to make frequent or significant changes independently. \| \| \| Mobility \| 1-Completely Immobile Does not make even slight changes in body or extremity position without assistance. \| Same interventions as for 2–Very Limited \| Nutrition Adequate nutrition and fluid intake are vital for maintaining healthy skin. Protein intake, in particular, is very important for healthy skin and wound healing. The nutrition risk factor is defined by two categories of descriptions. The first category measures the amount and type of oral intake. The second category is used for patients receiving tube feeding, total parenteral nutrition (TPN), or are prescribed clear liquid diets or nothing by mouth (NPO). See Table 10.5e for interventions for each level of risk from 1-4.Agency for Healthcare Research and Quality. (2014). Preventing pressure ulcers in hospitals. https://www.ahrq.gov/patient-safety/settings/hospital/resource/pressureulcer/tool/pu7b.htm Table 10.5e Interventions by Level of Risk for NutritionAgency for Healthcare Research and Quality. (2014). Preventing pressure ulcers in hospitals. https://www.ahrq.gov/patient-safety/settings/hospital/resource/pressureulcer/tool/pu7b.htm \| Assessment Category \| Rating Description \| Interventions \| \|---\|---\|---\| \| Nutrition \| 4–Excellent Eats most of every meal. Never refuses a meal. Usually eats a total of 4 or more servings of meat and dairy products. Occasionally eats between meals. Does not require supplementation. \| \| \| Nutrition \| 3–Adequate Eats over half of most meals. Eats a total of 4 servings of protein (meat and dairy products) each day. Occasionally refuses a meal, but will take a supplement if offered OR Is on a tube feeding or TPN regimen that most likely meets most of nutritional needs \| \| \| Nutrition \| 2–Probably Inadequate Rarely eats a complete meal and generally eats only about half of any food offered. Protein intake includes only 3 servings of meat or dairy products per day. Occasionally will take a dairy supplement OR Receives less than optimum amount of liquid diet or tube feeding. \| All interventions mentioned in 3–Adequate plus: \| \| Nutrition \| 1–Very Poor Never eats a complete meal. Rarely eats more than one third of any food offered. Eats two servings of protein (meat or dairy products) per day. Takes fluids poorly. Does not take a liquid dietary supplement OR Is NPO and/or maintained on clear liquids or IV for more than 5 days. \| All interventions mentioned in 2–Probably Inadequate plus: \| Friction/Shear Friction and shear are significant risk factors for producing pressure injuries. This category only has three ratings, unlike the other categories that have four ratings, and is rated by whether the patient has a problem, potential problem, or no apparent problem in this area. See Table 10.5f for interventions for each level of risk.Agency for Healthcare Research and Quality. (2014). Preventing pressure ulcers in hospitals. https://www.ahrq.gov/patient-safety/settings/hospital/resource/pressureulcer/tool/pu7b.htm Table 10.5f Descriptions and Interventions by Level of Risk for Friction/ShearAgency for Healthcare Research and Quality. (2014). Preventing pressure ulcers in hospitals. https://www.ahrq.gov/patient-safety/settings/hospital/resource/pressureulcer/tool/pu7b.htm \| Assessment Category \| Rating Description \| Interventions \| \|---\|---\|---\| \| Friction/Shear \| 3–No Apparent Problem Moves in bed and chair independently and has sufficient muscle strength to lift up completely during move. Maintains good position in bed or chair at all times. \| Keep bed linens clean, dry, and wrinkle free. \| \| Friction/Shear \| 2–Potential Problem Moves feebly or requires minimal assistance. During a move, skin probably slides to some extent against sheets, chair, restraints, or other devices. Maintains a relatively good position in a chair or bed most of the time but occasionally slides down. \| All interventions mentioned in 3–No Apparent Problem plus: \| \| Friction/Shear \| 1–Problem Requires moderate to maximum assistance in moving. Complete lifting without sliding against sheets is impossible. Frequently slides down in bed or chair, requiring frequent repositioning with maximum assistance. Spasticity, contractures, or agitation leads to almost constant friction. \| All interventions mentioned in 2–Potential Problem plus: \| Team Member Roles to Prevent Pressure Injuries Each member of the health care team has an important role in preventing the development of pressure injuries in at-risk patients. A registered nurse can delegate many interventions for preventing and treating a pressure injury to a licensed practical nurse (LPN) or to unlicensed assistive personnel such as a certified nursing assistant (CNA). See Table 10.5g for an explanation of the role of the RN in preventing pressure injuries, as well as tasks that can be delegated to LPNs and CNAs. Table 10.5g Team Member Roles in Preventing Pressure InjuriesAgency for Healthcare Research and Quality. (2014). Preventing pressure ulcers in hospitals. https://www.ahrq.gov/patient-safety/settings/hospital/resource/pressureulcer/tool/pu7b.htm \| Role \| Tasks \| \|---\|---\| \| RN \| \| \| LPN \| \| \| CNA \| \| 10.6 Applying the Nursing Process Open Resources for Nursing (Open RN) Assessment Subjective Assessment During a subjective assessment of a patient’s integumentary system, begin by asking about current symptoms such as itching, rashes, or wounds. If a patient has a wound, it is important to determine if a patient has pain associated with the wound so that pain management can be implemented. For patients with chronic wounds, it is also important to identify factors that delay wound healing, such as nutrition, decreased oxygenation, infection, stress, diabetes, obesity, medications, alcohol use, and smoking.Grey, J. E., Enoch, S., & Harding, K. G. (2006). Wound assessment. BMJ (Clinical research ed.), 332(7536), 285–288. https://doi.org/10.1136/bmj.332.7536.285 See Table 10.6a for a list of suggested interview questions to use when assessing a patient with a wound. If a patient has a chronic wound or is experiencing delayed wound healing, it is important for the nurse to assess the impact of the wound on their quality of life. Several studies have shown that patients with nonhealing wounds have a decreased quality of life. Reasons for this include the frequency and regularity of dressing changes, which affect daily routine; a feeling of continued fatigue due to lack of sleep; restricted mobility; pain; odor; and the side effects of multiple medications. The loss of independence associated with functional decline can also lead to changes in overall health and well-being. These changes include altered eating habits, depression, social isolation, and a gradual reduction in activity levels.Rosen, T. (2011). Inframammary candida intertrigo. UpToDate. https://somepomed.org/articulos/contents/mobipreview.htm?0/29/474 Table 10.6a Interview Questions Related to Integumentary Disorders \| Symptoms \| Questions \| Follow-up Questions \| \|---\|---\|---\| \| Current Symptoms \| Are you currently experiencing any skin symptoms such as itching, rashes, or an unusual mole? \| Please describe. \| \| Wounds \| Do you have any current wounds such as a surgical incision, skin tear, arterial ulcer, venous ulcer, diabetic or neuropathic ulcer, or a pressure injury? If a wound is present: \| Please describe. Use the PQRSTU method to comprehensively assess pain. Read more about the PQRSTU method in the “Pain Assessment Methods” section of the “Comfort” chapter. \| \| Medical History \| Have you ever been diagnosed with a wound related to diabetes, heart disease, or peripheral vascular disease? \| Please describe. \| \| If chronic wounds or wounds with delayed healing are present: \| \|\| \| Medications \| Are you taking any medications that can affect wound healing, such as oral steroids to treat inflammation or help you breathe? \| Please describe. \| \| Treatments \| What have you used to try to treat this wound? \| What was successful? Unsuccessful? \| \| Symptoms of Infection (pain, purulent drainage, etc.) \| Are you experiencing any symptoms of infection related to this wound such as increased pain or yellow/green drainage? \| Please describe. \| \| Stress \| Have you experienced any recent stressors such as surgery, hospitalization, or a change in life circumstances? \| How do you cope with stress in your life? \| \| Smoking \| Do you smoke? \| How many cigarettes do you smoke a day? How long have you smoked? Have you considered quitting smoking? \| \| Quality of Life \| Has this wound impacted your quality of life? \| Have you had any changes in eating habits, feelings of depression or social isolation, or a reduction in your usual activity levels? \| Objective Assessment When performing an objective integumentary assessment on a patient receiving inpatient care, it is important to perform a thorough exam on admission to check for existing wounds, as well as to evaluate their risk of skin breakdown using the Braden Scale. Agencies are not reimbursed for care of pressure injuries received during a patient’s stay, so existing wounds on admission must be well-documented. Routine skin assessment should continue throughout a patient’s stay, usually on a daily or shift-by-shift basis based on the patient’s condition. If a wound is present, it is assessed during every dressing change for signs of healing. See Table 10.6b for components to include in a wound assessment. See Figure 10.22“putool7bfig.jpg” by unknown is licensed under CC0. Access for free at https://www.ahrq.gov/patient-safety/settings/hospital/resource/pressureulcer/tool/pu7b.html. for an image of a common tool used to document the location of a skin concern found during assessment. Read more information about performing an overall integumentary assessment in the “Integumentary Assessment” chapter in Open RN Nursing Skills. For additional discussion regarding assessing wounds, go to the “Assessing Wounds” section of the “Wound Care” chapter in Open RN Nursing Skills. Table 10.6b Wound Assessment \| Wound Assessment \| \| \|---\|---\| \| Type \| Types of wounds may include abrasions, lacerations, burns, surgical incisions, pressure injuries, skin tears, arterial ulcers, or venous ulcers. It is important to understand the type of wound present to select appropriate interventions. \| \| Location \| The location of the wound should be documented precisely. A body diagram template is helpful to demonstrate exactly where the wound is located. \| \| Size \| Wound size should be measured regularly to determine if the wound is increasing or decreasing in size. Length is measured using the head-to-toe axis, and width is measured laterally. If tunneling or undermining is present, their depth should be assessed using a sterile, cotton-tipped applicator and documented using the clock method. \| \| Degree of Tissue Injury \| Wounds are classified as partial-thickness (meaning the epidermis and dermis are affected) or full-thickness (meaning the subcutaneous and deeper layers are affected). See Figure 10.1 in the “Basic Concepts” section for an image of the layers of skin. For pressure injuries, it is important to assess the stage of the injury (see information on staging under the “Pressure Injuries” subsection). \| \| Color of Wound Base \| Assess the base of the wound for the presence of healthy, pink/red granulation tissue. Note the unhealthy appearance of dark red granulation tissue, white or yellow slough, or brown or black necrotic tissue. \| \| Drainage \| The color, consistency, and amount of exudate (drainage) should be assessed and documented at every dressing change. Drainage from wounds is often described as scant, small/minimal, moderate, and large/copious amounts. Use the following descriptions to select the appropriate terms:Wound Care Advisor. (n.d.). Exudate amounts. https://woundcareadvisor.com/exudate-amounts/#:~:text=Small%20or%20minimal%20amount%20of,than%2075%25%20of%20the%20bandage The type of wound drainage should be described using medical terms such as serosanguinous, sanguineous, serous, or purulent: \| \| Tubes or Drains \| Check for patency and if they are attached correctly. \| \| Signs and Symptoms of Infection \| Assess for signs and symptoms of infection, which include the following: \| \| Wound Edges and Periwound \| Assess the surrounding skin for maceration or signs of infection. \| \| Pain \| Assess for pain in the wound or during dressing changes. If pain is present, use the PQRSTU or OLDCARTES method to obtain a comprehensive pain assessment. \| See Table 10.6c for a comparison of expected versus unexpected findings on integumentary assessment. Table 10.6c Expected Versus Unexpected Findings \| Assessment \| Expected Findings \| Unexpected Findings \| \|---\|---\|---\| \| Skin \| Color: appropriate for ethnicity Temperature: warm to touch Texture: smooth, soft, and supple Turgor: resilient Integrity: no wounds or lesions noted Sensory: no pain or itching noted \| Color: pale, white, red, yellow, purple, black and blue Temperature: cool or hot to touch Texture: rough, scaly or thick; thin and easily torn; dry and cracked Turgor: tenting noted Integrity: rashes, lesions, abrasions, burns, lacerations, surgical wounds, pressure injuries noted Pain or pruritus (itching) present \| \| Hair \| Full distribution of hair on the head, axilla, and genitalia \| Alopecia (hair loss), hirsutism (excessive hair growth over body), lice and/or nits, or lesions under hair \| \| Nails \| Smooth, well-shaped, and firm but flexible \| Cracked, chipped, or splitting nail; excessively thick; presence of clubbing; ingrown nails \| \| Skin Integrity \| Skin intact with no wounds or pressure injuries. Braden Scale is 23 \| A wound or pressure injury is present, or there is risk of developing a pressure injury with a Braden scale score of less than 23 \| Diagnostic and Lab Work When a chronic wound is not healing as expected, laboratory test results can provide additional clues for the delayed healing. See Table 10.6d for a summary of lab results that offer clues to systemic issues causing delayed wound healing.Rosen, T. (2011). Inframammary candida intertrigo. UpToDate. https://somepomed.org/articulos/contents/mobipreview.htm?0/29/474 Table 10.6d Lab Values Associated with Delayed Wound HealingGrey, J. E., Enoch, S., & Harding, K. G. (2006). Wound assessment. BMJ (Clinical research ed.), 332(7536), 285–288. https://doi.org/10.1136/bmj.332.7536.285 \| Abnormal Lab Value \| Rationale \| \|---\|---\| \| Low hemoglobin \| Low hemoglobin indicates less oxygen is transported to the wound site. \| \| Elevated white blood cells (WBC) \| Increased WBC indicates infection is occurring. \| \| Low platelets \| Platelets have an important role in the creation of granulation tissue. \| \| Low albumin \| Low albumin indicates decreased protein levels. Protein is required for effective wound healing. \| \| Elevated blood glucose or hemoglobin A1C \| Elevated blood glucose and hemoglobin A1C levels indicate poor management of diabetes mellitus, a disease that negatively impacts wound healing. \| \| Elevated serum BUN and creatinine \| BUN and creatinine levels are indicators of kidney function, with elevated levels indicating worsening kidney function. Elevated BUN (blood urea nitrogen) levels impact wound healing. \| \| Positive wound culture \| Positive wound cultures indicate an infection is present and provide additional information including the type and number of bacteria present, as well as identifying antibiotics the bacteria is susceptible to. The nurse reviews this information when administering antibiotics to ensure the prescribed therapy is effective for the type of bacteria present. \| Life Span and Cultural Considerations Newborns and Infants Newborn skin is thin and sensitive. It tends to be easy to scratch and bruise and is susceptible to rashes and irritation. Common rashes seen in newborns and infants include diaper rash (contact dermatitis), cradle cap (seborrheic dermatitis), newborn acne, and prickly heat. Toddlers and Preschoolers Because of high levels of activity and increasing mobility, this age group is more prone to accidents. Issues like lacerations, abrasions, burns, and sunburns can occur frequently. It is important to be highly aware of the potential for accidents and implement safety precautions as needed. School-Aged Children and Adolescents Skin rashes tend to affect skin within this age group. Impetigo, scabies, and head lice are commonly seen and may keep children home from school. Acne vulgaris typically begins during adolescence and can alter physical appearance, which can be very upsetting to this age group. Another change during adolescence is the appearance of axillary, pubic, and other body hair. Also, as these children spend more time out of doors, sunburns are more common, and care should be given to encourage sunscreen and discourage the use of tanning beds. Adults and Older Adults As skin ages, many changes take place. Decreased sweat gland activity leads to drier skin and pruritus (itching). Healing is slowed because of reduced circulation and the inability of proteins and proper nutrients to arrive at injury sites. Hair loses pigmentation and turns gray or white. Nails become thicker and are more difficult to cut. Age or liver spots become darker and more noticeable. The number of skin growths increases and includes skin tags and keratoses. There is often delayed wound healing in older adults. Diagnoses There are several NANDA-I nursing diagnoses related to patients experiencing skin alterations or those at risk of developing a skin injury. See Table 10.6e for common NANDA-I nursing diagnoses and their definitions.Herdman, T., & Kamitsuru, S. (2017). NANDA international nursing diagnoses: Definitions & classification 2018-2020 (11th ed.). Thieme Publishers. pp. 404, 406, 407, 412, 413. Table 10.6e Common NANDA-I Nursing Diagnoses Related to Integumentary DisordersHerdman, T., & Kamitsuru, S. (2017). NANDA international nursing diagnoses: Definitions & classification 2018-2020 (11th ed.). Thieme Publishers. pp. 404, 406, 407, 412, 413. \| Risk for Pressure Injury: “Susceptible to localized injury to the skin and/or underlying tissue usually over a bony prominence as a result of pressure, or pressure in combination with shear.” \| \| Impaired Skin Integrity: “Altered epidermis and/or dermis.” \| \| Risk for Impaired Skin Integrity: “Susceptible to alteration in epidermis and/or dermis, which may compromise health.” \| \| Impaired Tissue Integrity: “Damage to the mucous membrane, cornea, integumentary system, muscular fascia, muscle, tendon, bone, cartilage, joint capsule, and/or ligament.” \| \| Risk for Impaired Tissue Integrity: “Susceptible to damage to the mucous membrane, cornea, integumentary system, muscular fascia, muscle, tendon, bone, cartilage, joint capsule, and/or ligament, which may compromise health.” \| A commonly used NANDA-I nursing diagnosis for patients experiencing alterations in the integumentary system is Impaired Tissue Integrity, defined as, “Damage to the mucous membrane, cornea, integumentary system, muscular fascia, muscle, tendon, bone, cartilage, joint capsule, and/or ligament.” To verify accuracy of this diagnosis for a patient, the nurse compares assessment findings with defining characteristics of that diagnosis. Defining characteristics for Impaired Tissue Integrity include the following: - Acute pain - Bleeding - Destroyed tissue - Hematoma - Localized area hot to touch - Redness - Tissue damage A sample NANDA-I diagnosis in current PES format would be: “Impaired Tissue Integrity related to insufficient knowledge about protecting tissue integrity as evidenced by redness and tissue damage.” Outcome Identification An example of a broad goal for a patient experiencing alterations in tissue integrity is: - The patient will experience tissue healing. A sample SMART expected outcome for a patient with a wound is: - The patient’s wound will decrease in size and have increased granulation tissue within two weeks. Planning Interventions In addition to the interventions outlined under the “Braden Scale” section to prevent and treat pressure injury, see the following box for a list interventions to prevent and treat impaired skin integrity. As always, consult a current, evidence-based nurse care planning resource for additional interventions when planning patient care. Selected Interventions to Prevent and Treat Impaired Skin Integrity Butcher, H., Bulechek, G., Dochterman, J., & Wagner, C. (2018). Nursing interventions classification (NIC). Elsevier. pp. 348-349, 417-419.,Ackley, B., Ladwig, G., & Makic, M. B. (2016). Nursing diagnosis handbook: An evidence-based guide to planning care (11th ed.). pp. 884-885. Elsevier.,Cox, J. (2019). Wound care 101. Nursing, 49(10), 32-39. https://doi.org/10.1097/01.nurse.0000580632.58318.08 - Assess and document the patient’s skin status routinely. (Frequency is determined based on the patient’s status.) - Use the Braden Scale to identify patients at risk for skin breakdown. Customize interventions to prevent and treat skin breakdown according to patient needs. - If a wound is present, evaluate the healing process at every dressing change. Note and document characteristics of the wound, including size, appearance, staging (if applicable), and drainage. Notify the provider of new signs of infection or lack of progress in healing. - Provide wound care treatments, as prescribed by the provider or wound care specialist, and monitor the patient’s response toward expected outcomes. - Cleanse the wound per facility protocol or as ordered. - Maintain non-touch or aseptic technique when performing wound dressing changes, as indicated. (Read more details about using aseptic technique and the non-touch method in the “Aseptic Technique” chapter of the Open RN Nursing Skills textbook.) - Change wound dressings as needed to keep them clean and dry and prevent bacterial reservoir. - Monitor for signs of infection in an existing wound (as indicated by redness, warmth, edema, increased pain, reddened appearance of surrounding skin, fever, increased white blood cell count, changes in wound drainage, or sudden change in patient’s level of consciousness). - Apply lotion to dry areas to prevent cracking. - Apply lubricant to moisten lips and oral mucosa, as needed. - Keep skin free of excess moisture. Use moisture barrier ointments (protective skin barriers) or incontinence products in skin areas subject to increased moisture and risk of skin breakdown. - Educate the patient and/or family caregivers on caring for the wound and request return demonstrations, as appropriate. - Administer medications, as prescribed, and monitor for expected effects. - Consult with a wound specialist, as needed. - Obtain specimens of wound drainage for wound culture, as indicated, and monitor results. - Advocate for pressure-relieving devices in patients at risk for pressure injuries, such as elbow protectors, heel protectors, chair cushions, and specialized mattresses and monitor the patient’s response. - Promote adequate nutrition and hydration intake, unless contraindicated. - Use a minimum of two-person assistance and a draw sheet to pull a patient up in bed to minimize shear and friction. - Reposition the patient frequently to prevent skin breakdown and to promote healing. Turn the immobilized patient at least every two hours, according to a specific schedule. - Maintain a patient’s position at 30 degrees or less, as appropriate, to prevent shear. - Keep bed linens clean, dry, and wrinkle free. Implementation Before implementing interventions, it is important to assess the current status of the skin and risk factors present for skin breakdown and modify interventions based on the patient’s current status. For example, if a patient’s rash has resolved, some interventions may no longer be appropriate (such as applying topical creams). However, if a wound is showing signs of worsening or delayed healing, additional interventions may be required. As always, if the patient demonstrates new signs of localized or systemic infection, the provider should be notified. Evaluation It is important to evaluate for healing when performing wound care. Use the following expected outcomes when evaluating wound healing: - Resolution of periwound redness in 1 week - 50% reduction in wound dimensions in 2 weeks - Reduction in volume of exudate - 25% reduction in amount of necrotic tissue/eschar in 1 week - Decreased pain intensity during dressing changesBryant, R. A., & Nix, D. P. (2010). Acute and chronic wounds: Current management concepts (4th ed.). Elsevier. If a patient is experiencing delayed wound healing or has a chronic wound, it is helpful to advocate for a referral to a wound care nurse specialist. Read a sample nursing care plan for a patient with impaired skin integrity. 10.7 Putting It All Together Open Resources for Nursing (Open RN) Review the following example of applying the nursing process to a patient with a pressure injury. Patient Scenario Betty Pruitt is a 92-year-old female admitted to a skilled nursing facility after a fall at her daughter’s home while transferring the patient from her bed to a wheelchair. See Figure 10.24 for an image of Betty Pruitt.“1068481.jpg” by unknown is licensed under CC0Although no injury was sustained, it became clear to the family that they could no longer provide adequate care at home. Ms. Pruitt’s past medical history includes congestive heart failure, hypertension, hypercholesterolemia, and moderate stage Alzheimer’s disease. Her cognitive ability has significantly declined over the last six months. Patient’s speech continues to be mostly clear and at times coherent but she tends to be quiet and does not express her needs adequately, even with prompting. She no longer has the ability to ambulate but can stand for short periods of time, requiring two people to transfer. She rarely changes body position without encouragement and assistance, spending most of her days in a recliner or bed. Betty is 69 inches tall and currently weighs 122 pounds, having lost 22 pounds over the last 3 months. BMI is 18. Family reports her appetite is poor, and she eats only in small amounts at meal times with feeding assistance. She does take liquids well and shows no swallowing difficulties at this time. Betty is incontinent of urine and stool most of the time but will use the toilet if offered and given transfer help. Unknown to the family, a skin assessment revealed a Stage III pressure injury on coccyx area. Wound measures 4 cm long, 4 cm wide, 3 cm deep, with adipose tissue visible. No undermining, tunneling, bone, muscle, or tendons visible. Scant amount of yellowish purulent drainage noted. Slight foul odor, with redness, and increased heat around the wound present. A Braden Scale Risk Assessment was completed and revealed a total score of 12 (High Risk) with the following category scores: Sensory Perception-3, Moisture-2, Activity-2, Mobility-2, Nutrition-2, Friction & Shear-1. Applying the Nursing Process Based on this information, the following nursing care plan was implemented for Ms. Pruitt. Nursing Diagnosis: Impaired Tissue Integrity related to imbalanced nutritional state and associated with impaired mobility as evidenced by damaged tissue, redness, area hot to touch. Overall Goal: The patient will experience wound healing demonstrated by decreased wound size and increased granulation tissue. SMART Expected Outcome: Ms. Pruitt will have a 50% reduction in wound dimensions (from 4 cm in diameter to 2 cm) within two weeks. Planned Nursing Interventions with Rationale: See Table 10.7 for a list of planned nursing interventions with rationale. Table 10.7 Selected Interventions and Rationale for Ms. Pruitt \| Interventions \| Rationale \| \|---\|---\| \| 1. Assess and document wound characteristics every shift, including size (length x width x depth), stage (I-IV), location, exudate, presence of granulation tissue, and epithelization. \| Consistent and accurate documentation of wounds is important in determining the progression of wound healing and effectiveness of treatments. \| \| 2. Monitor for signs of infection (color, temperature, edema, moisture, pain, and appearance of surrounding skin). \| Frequent monitoring for possible wound infection provides the ability to intervene quickly if changes in the wound are noted. Additionally, pain medications should be offered prior to dressing changes if pain is present. \| \| 3. Cleanse wound per facility protocol or as ordered. \| Removal of exudate, dirt, and slough promotes wound healing. \| \| 4. Cleanse the periwound area (skin around the wound) with mild soap and water. \| Decreasing the number of microorganisms around the wound may decrease the chance of wound infection. \| \| 5. Apply and change wound dressings, per facility protocol or wound orders. \| Dressings that maintain moisture in the wound keep periwound skin dry, absorb drainage, and pad the wound to protect from further injury assist in healing. \| \| 6. Turn/reposition the patient every 2 hours and position with pillows as needed. \| Frequent repositioning relieves pressure point areas from damage. Avoid positioning the patient directly on an injured area if possible. \| \| 7. Consider the use of a specialty mattress, bed, or chair pad. \| Specialty mattresses, beds, or pads offer added padding and support, while decreasing pressure areas. \| \| 8. Use moisture barrier ointments (protective skin barriers). \| Moisture barrier ointments can significantly decrease skin breakdown and pressure injury formation. \| \| 9. Check incontinence pads frequently (every 2-3 hours) and change as needed to keep dry. \| Frequent changing of soiled pads will prevent exposure to chemicals in urine and stool that erode the skin. \| \| 10. Monitor nutritional status and obtain order for dietary consult if needed. \| Optimizing nutritional intake, including calories, protein, and vitamins, is essential to promote wound healing. \| \| 11. Offer nutritional supplements and water. \| Nutritional supplements, such as protein shakes, can provide additional calories and protein without a large volume of intake needed. Water intake is essential for proper tissue hydration. \| \| 12. Keep bed linens clean, dry, and wrinkle free. \| Soiled, wet, or wrinkled sheets may contribute to skin breakdown. \| \| 13. Use a minimum of two-person assistance and a draw sheet to pull the patient up in bed. \| Carefully transferring patients avoids adverse effects of external mechanical forces (pressure, friction, and shear) from causing skin or tissue damage. \| Interventions Implemented: After the admission assessment was completed, Ms. Pruitt became settled in her new room. The wound was assessed, documented, and cleaned. A specimen for wound culture was obtained and a wound dressing applied per protocol. The health care provider was notified of the wound. Requests were made for a wound culture, referrals to a wound care nurse specialist and a dietician, and a pressure-relieving mattress for the bed. A two-hour turning schedule was implemented, and the CNA was reminded to use two-person assistance with a lift sheet when repositioning the patient. A barrier cream was applied to protect the peri-area whenever a new incontinence pad was placed. The following documentation note was entered in the patient chart. Documentation: On admission, a Stage III pressure injury was discovered on the patient’s coccyx area. The wound measured 4 cm long, 4 cm wide, 3 cm deep, with adipose tissue visible. No undermining, tunneling, bone, muscle, or tendons visible. A small amount of yellow purulent drainage noted. Slight foul odor, with redness, and increased heat around the wound present. Wound was cleaned with normal saline and packed with moist gauze and covered with hydrogel dressing. Patient tolerated the procedure well and gave no evidence of pain. A pressure-relieving mattress was placed on the patient’s bed and a two-hour turning schedule was implemented. Patient voided x 1 and the pad was changed. Barrier cream was applied to the perineal area. Patient encouraged to rest until lunchtime and is resting. Evaluation: After two weeks, the measurements of the wound were compared to those on admission and the wound decreased in size to less than 2 cm. The expected outcome was “met.” A new expected outcome was established, “Mrs. Pruitt’s wound will resolve within the next 2 weeks.” The same planned interventions were continued to be implemented. 10.8 Learning Activities Open Resources for Nursing (Open RN) Learning Activities (Answers to “Learning Activities” can be found in the “Answer Key” at the end of the book. Answers to interactive activity elements will be provided within the element as immediate feedback.) You have been assigned to care for Mr. Johns, a 74-year-old client recently diagnosed with a urinary tract infection, resulting in frequent incontinence. Mr. Johns suffered a CVA (stroke) six months ago and has difficulties ambulating and attending to his own needs because of weakness on his right side. Mr. Johns is alert and oriented to person, place, and time, but has decreased sensation on his entire right side. He spends most of his time in bed or sitting at his bedside in a wheelchair due to his difficulty with ambulation. He eats about 50% of his meals. While assessing Mr. Johns, you note that he is thin for his height, incontinent of foul-smelling urine, and has a deepened reddened area on his sacrum. - What additional information, including lab work, would you like to gather to further assess Mr. Johns’ potential for pressure injury development? - What factors make him particularly vulnerable to the development of pressure injuries? An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=575#h5p-90 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=575#h5p-22 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=575#h5p-23 X Glossary Open Resources for Nursing (Open RN) Angiogenesis: The process of wound healing when new capillaries begin to develop within the wound 24 hours after injury to bring in more oxygen and nutrients for healing. Approximated edges: The well-closed edges of a wound healing by primary intention. Arterial insufficiency: A condition caused by lack of adequately oxygenated blood supply to specific tissues. Braden Scale: A standardized assessment tool used to assess and document a patient’s risk factors for developing pressure injuries. Deep tissue pressure injuries: Persistent; non-blanchable; deep red, maroon, or purple discoloration of intact or nonintact skin revealing a dark wound bed or blood-filled blister. Pain and temperature change often precede skin color changes. Discoloration may appear differently in darkly pigmented skin. Dehiscence: The separation of a surgical incision. Dermis: The layer of skin underneath under the epidermis, containing hair follicles, sebaceous glands, blood vessels, endocrine sweat glands, and nerve endings. Epidermis: The very thin, top layer of the skin that contains openings of the sweat gland ducts and the visible part of hair known as the hair shaft. Epithelialization: The development of new epidermis and granulation tissue in a healing wound. Eschar: Dark brown/black, dry, thick, and leathery dead tissue in wounds. Excoriation: Redness and removal of the surface of the topmost layer of skin, often due to maceration or itching. Friction: The rubbing of skin against a hard object, such as the bed or the arm of a wheelchair. This rubbing causes heat that can remove the top layer of skin and often results in skin damage. Granulation tissue: New connective tissue in a healing wound with new, fragile, thin-walled capillaries. Hemostasis phase of wound healing: The first stage of wound healing when clotting factors are released to form clots to stop the bleeding. Hypodermis: The bottom layer of skin, also referred to as the subcutaneous layer, consisting mainly of adipose tissue or fat, along with some blood vessels and nerve endings. Beneath this layer lies muscles, tendons, ligaments, and bones. Impaired skin integrity: Altered epidermis and/or dermis. Impaired tissue integrity: Damage to deeper layers of the skin or other integumentary structures. The NANDA-I definition of impaired tissue integrity is, “Damage to the mucous membrane, cornea, integumentary system, muscular fascia, muscle, tendon, bone, cartilage, joint capsule, and/or ligament.” Inflammatory phase of wound healing: The second stage of healing when vasodilation occurs to move white blood cells into the wound to start cleaning the wound bed. Maceration: A condition that occurs when skin has been exposed to moisture for too long causing it to appear soggy, wrinkled, or whiter than usual. Maturation phase: The final stage of wound healing when collagen continues to be created to strengthen the wound and prevent it from reopening. Necrosis: Tissue death. Necrotic: Dead tissue that is black. Nonblanchable erythema: Skin redness that does not turn white when pressed. Osteomyelitis: Bone infection. Pressure injuries: Localized damage to the skin or underlying soft tissue, usually over a bony prominence, as a result of intense and prolonged pressure in combination with shear. Primary intention: A type of wound that is sutured, stapled, glued, or otherwise closed so the wound heals beneath the closure. Proliferative phase of wound healing: The third stage of wound healing that begins a few days after injury and includes four processes: epithelialization, angiogenesis, collagen formation, and contraction. Purulent: Drainage that is thick; opaque; tan, yellow, green, or brown in color. New purulent drainage should always be reported to the health care provider. Sanguineous: Drainage from a wound that is fresh bleeding. Secondary intention: A type of healing that occurs when the edges of a wound cannot be brought together, so the wound fills in from the bottom up by the production of granulation tissue. An example of a wound healing by secondary intention is a pressure ulcer. Serosanguinous: Serous drainage with small amounts of blood present. Serous: Drainage from a wound that is clear, thin, watery plasma. It’s normal during the inflammatory stage of wound healing, and small amounts are considered normal wound drainage. Shear: Damage that occurs when tissue layers move over the top of each other, causing blood vessels to stretch and break as they pass through the subcutaneous tissue. Slough: Inflammatory exudate in wounds that is usually light yellow, soft, and moist. Stage 1 pressure injuries: Intact skin with a localized area of nonblanchable erythema where prolonged pressure has occurred. The wound bed is viable and may appear like an intact or ruptured blister. The depth of tissue damage varies by anatomical location. Undermining and tunneling may be present. If slough or eschar obscures the wound so that tissue loss cannot be assessed, the pressure injury is referred to as unstageable. Tertiary intention: The healing of a wound that has had to remain open or has been reopened, often due to severe infection. Tunneling: Passageways underneath the surface of the skin that extend from a wound and can take twists and turns. Undermining: A condition that occurs in wounds when the tissue under the wound edges becomes eroded, resulting in a pocket beneath the skin at the wound’s edge. Unstageable pressure injuries: Full-thickness skin and tissue loss in which the extent of tissue damage within the ulcer cannot be confirmed because it is obscured by slough or eschar. Venous insufficiency: A condition that occurs when the cardiovascular system cannot adequately return blood and fluid from the extremities to the heart. Comfort XI 11.1 Comfort Introduction Open Resources for Nursing (Open RN) Learning Objectives - Assess patients for subjective and objective manifestations of alterations in comfort - Identify factors related to comfort across the life span - Adhere to standards of care for the patient experiencing pain - Identify nonpharmacologic measures to minimize pain and discomfort - Outline the plan for monitoring the patient response to the interventions for pain and discomfort - Identify evidence-based practices related to assessing pain and providing comfort Pain is a universal sensation that everyone experiences, and acute pain is a common reason why patients seek medical care. Nurses work with the interdisciplinary team to assess and manage pain in a multidimensional approach to provide comfort and prevent suffering. This chapter will review best practices and standards of care for the assessment and management of pain. 11.2 Comfort Basic Concepts Open Resources for Nursing (Open RN) Definitions of Pain Pain has been defined as, “Whatever the patient says it is, experienced whenever they say they are experiencing it.”Pasero, C., & MacCaffery, M. (2010). Pain assessment and pharmacological management (1st ed.). Mosby. In 2020 the International Association for the Study of Pain (IASP) released a revised definition of pain as, “An unpleasant sensory and emotional experience associated with, or resembling that associated with, actual or potential tissue damage,” along with these additional notes: - Pain is always a personal experience that is influenced to varying degrees by biological, psychological, and social factors. - Individuals learn the concept of pain throughout all stages of their life. - A person’s report of an experience as pain should be respected. - Although pain usually serves an adaptive role, it can have adverse effects on function, socialization, and psychological well-being. - Verbal description is only one of several behaviors that express pain. The inability to communicate does not negate the possibility that a person is experiencing pain.International Association for the Study of Pain. (2017, December 14). IASP terminology. https://www.iasp-pain.org/Education/Content.aspx?ItemNumber=1698 Pain motivates the individual to withdraw from dangerous stimuli, to protect a damaged body part while it heals, and to avoid similar experiences in the future. Most pain resolves after the painful stimulus is removed and the body has healed, but sometimes pain persists despite removal of the stimulus and apparent healing of the body. Additionally, pain can occur in the absence of any detectable stimulus, damage, or disease.This work is a derivative of Anatomy and Physiology by Boundless and is licensed under CC BY-SA 4.0 Physiology of Pain Let’s begin by reviewing the physiological processes of pain. A nociceptor is a type of sensory receptor that responds to potentially damaging stimuli by sending nerve signals to the spinal cord and brain in a process called nociception. There are several types and functions of nociceptors: - Thermal nociceptors are activated by noxious heat or cold, such as a hot pan. - Mechanical nociceptors are activated by excess pressure or mechanical deformation, such as a finger getting caught in a car door. They also respond to incisions that break the skin surface. - Chemical nociceptors are activated by a wide variety of spices commonly used in cooking. For example, capsaicin is a compound in chili peppers that causes a burning sensation of the mucus membranes. It is also used in common over-the-counter creams for pain relief because when it is applied to the skin, it blocks the transmission of pain impulses.This work is a derivative of Anatomy and Physiology by Boundless and is licensed under CC BY-SA 4.0 Noxious stimuli are detected by nociceptors and transduced into electrical energy. An action potential is created and transmitted along nociceptor fibers. There are two types of nociceptor fibers, A-Delta and C. A-Delta fibers are fast-conducting fibers and associated with the initial sharp, stinging, or pricking pain sensation. C fibers are slower-conducting fibers and are associated with the secondary sensation of diffuse, dull, burning, and aching pain. The pain impulse is transmitted along these nociceptor fibers to the dorsal horn in the spinal cord and then from the spinal cord to the thalamus, where pain messages are relayed to the cerebral cortex. In the cerebral cortex, pain impulses are perceived and the conscious awareness of pain occurs.This work is a derivative of Anatomy and Physiology by Boundless and is licensed under CC BY-SA 4.0,NursingTimes. (2008, September 18). Anatomy and physiology of pain. https://www.nursingtimes.net/clinical-archive/pain-management/anatomy-and-physiology-of-pain-18-09-2008/#:~:text=The%20transmission%20process%20occurs%20in,higher%20levels%20of%20the%20brain See Figure 11.1“Sketch colored final.png” by Bettina Guebeli is licensed under CC BY-SA 4.0) for an illustration of how the pain signal is transmitted from the nociceptors to the spinal cord and then to the brain. View supplementary videos on pain: - Karen D. Davis: How does your brain respond to pain? \| TED Talk - A one-minute review of how pain receptors work: Feeling Pain Types of Pain Pain can be divided into visceral, deep somatic, superficial, and neuropathic pain. - Visceral structures are highly sensitive to stretch, ischemia, and inflammation. Visceral pain is diffuse, difficult to locate, and often referred to a distant, usually superficial, structure. It may be accompanied by nausea and vomiting and may be described as sickening, deep, squeezing, and dull.This work is a derivative of Anatomy and Physiology by Boundless and is licensed under CC BY-SA 4.0 - Deep somatic pain is initiated by stimulation of nociceptors in ligaments, tendons, bones, blood vessels, fascia, and muscles and is a dull, aching, poorly localized pain. Examples include sprains and broken bones.This work is a derivative of Anatomy and Physiology by Boundless and is licensed under CC BY-SA 4.0 - Superficial pain is initiated by the activation of nociceptors in the skin or other superficial tissue and is sharp, well-defined, and clearly located. Examples of injuries that produce superficial somatic pain include minor wounds and minor (first-degree) burns.This work is a derivative of Anatomy and Physiology by Boundless and is licensed under CC BY-SA 4.0 - Neuropathic pain is defined by the International Association for the Study of Pain (IASP) as pain caused by a lesion or disease of the somatosensory nervous system. It is typically described by patients as “burning” or “like pins and needles.” Neuropathic pain can be caused by several disease processes, such as diabetes mellitus, strokes, and HIV, and is generally undertreated because it typically does not respond to analgesics. Medications such as tricyclic antidepressants and gabapentin are typically used to manage this type of pain.Murnion, B. P. (2018). Neuropathic pain: Current definition and review of drug treatment. Australian Prescriber, 41(3), 60–63. https://doi.org/10.18773/austprescr.2018.022 Pain can radiate from one area to another. For example, back pain caused by a herniated disk can cause pain to radiate down an individual’s leg. Referred pain is different from radiating pain because it is perceived at a location other than the site of the painful stimulus. For example, pain from retained gas in the colon can cause pain to be perceived in the shoulder. See Figure 11.2“1506_Referred_Pain_Chart.jpg” by OpenStax is licensed under CC BY 3.0. Access for free at https://cnx.org/contents/C650g-ah@2/Autonomic-Reflexes-and-Homeostasis for an illustration of common sites of referred pain. Factors Affecting the Pain Experience There are many biological, psychological, and social factors that affect the perception of pain, making it a unique, individual experience. See Table 11.2a for a list of these factors.Pain Management Best Practices Inter-Agency Task Force. (2019, May 9). Pain management best practices. U.S. Department of Health and Human Services. https://www.hhs.gov/sites/default/files/pmtf-final-report-2019-05-23.pdf Nurses must consider these factors while assessing and providing holistic nursing care for patients experiencing pain. Table 11.2a Biological, Psychological, and Social Factors Affecting Pain \| Biological Factors \| Psychological Factors \| Social Factors \| \|---\|---\|---\| \| \| \| Acute vs. Chronic Pain Pain is differentiated between acute pain and chronic pain. Acute pain has limited duration and is associated with a specific cause. It usually causes a physiological response resulting in increased pulse, respirations, and blood pressure. Diaphoresis (sweating, especially to an unusual degree) may also occur. Examples of acute pain include postoperative pain; burns; acute musculoskeletal conditions like strains, sprains, and fractures; labor and delivery; and traumatic injury. Chronic pain is ongoing and persistent for longer than six months. It typically does not cause a change in vital signs or diaphoresis. It may be diffuse and not confined to a specific area of the body. Chronic pain often affects an individual’s psychological, social, and behavioral responses that can influence daily functioning. Chronic medical problems, such as osteoarthritis, spinal conditions, fibromyalgia, and peripheral neuropathy, are common causes of chronic pain. Chronic pain can continue even after the original injury or illness that caused it has healed or resolved. Some people suffer chronic pain even when there is no past injury or apparent body damage. People who have chronic pain often have physical effects that are stressful on the body. These effects include tense muscles, limited ability to move around, lack of energy, and appetite changes. Emotional effects of chronic pain include depression, anger, anxiety, and fear of reinjury. These effects can limit a person’s ability to return to their regular work or leisure activities.Cleveland Clinic. (2020, December 8). Acute v. chronic pain. https://my.clevelandclinic.org/health/articles/12051-acute-vs-chronic-pain It is estimated that chronic pain affects 50 million U.S. adults, and 19.6 million of those adults experience high-impact chronic pain that interferes with daily life or work activities.Pain Management Best Practices Inter-Agency Task Force. (2019, May 9). Pain management best practices. U.S. Department of Health and Human Services. https://www.hhs.gov/sites/default/files/pmtf-final-report-2019-05-23.pdf See Figure 11.3“Lower_back_pain.jpg” by Injurymap is licensed under CC BY 4.0 for an illustration of low back pain, an example of both acute and chronic pain that often affects daily functioning. Read additional information about pain using the following hyperlinks: Life Span and Cultural Considerations The pain experience varies across the life span. Newborns and infants can feel pain but are unable to verbalize it. Repetitive and prolonged pain may be associated with altered pain sensitivity and pain processing later in life. Toddlers and preschoolers often have difficulty describing, identifying, and locating pain. Instead, pain may be demonstrated behaviorally with crying, anger, physical resistance, or withdrawal. School-age children and adolescents may try to be “brave” and rationalize the pain; they are more responsive to explanations about pain. Older adults are at increased risk for undertreatment of pain. It is estimated that up to 70% of older adults in the community and up to 85% living in long-term care centers have significant pain due to chronic conditions such as osteoarthritis and peripheral neuropathy. Pain is often underassessed in older adults because they are less likely to report it and also because it can present atypically with confusion and agitation.American Association of Colleges of Nursing. (n.d.). End-of-Life-Care (ELNEC). https://www.aacnnursing.org/ELNEC Other special populations who are at increased risk for the undertreatment of pain include the following: - Patients with a history of addictive disease - Nonverbal, cognitively impaired, or unconscious patients - Patients who endure pain without complaining due to cultural or religious beliefs - Non-English speaking patients where communicating is a barrier - Uninsured or underinsured patients where cost of medications is a barrierAmerican Association of Colleges of Nursing. (n.d.). End-of-Life-Care (ELNEC). https://www.aacnnursing.org/ELNEC Nurses must be especially vigilant of nonverbal signs of pain in these at-risk groups and implement appropriate assessment tools and interventions. Read an example of a patient with untreated pain in the following box. A True Story of Undertreated Pain A teenage boy from the Amish community was admitted to the hospital after he sustained several fractures when his buggy was hit by a motor vehicle. His parents stayed at his bedside throughout his hospital stay. The nurses noticed that although he denied pain, he grimaced and guarded the body parts that were injured. He moaned when repositioned and declined to get out of bed to begin physical therapy when it was prescribed for rehabilitation. However, despite these nonverbal indicators of pain, he continued to deny the existence of pain and refused all pain medication. One day, when his parents left the room briefly to get coffee, the nurse said to the patient, “Most people in your situation experience severe pain. I can see that you are hurting by your expressions when you move. Can you help me to understand why you don’t want any pain medication?” A tear began to fall down the boy’s cheek. He explained that his community does not believe in complaining about pain and to be a man, he must learn how to tolerate suffering. The nurse explained, “It is important for you to attend physical therapy so that you can heal and go home. Can we bring you pain pills every day before physical therapy so that you can participate in the exercises, recover quickly, and go home?” The boy agreed to this plan. The nurse documented her findings and made notes in the care plan to administer the prescribed PRN pain medications one hour before physical therapy was scheduled. She also communicated her findings during the nurse handoff report. The boy was able to satisfactorily complete the prescribed physical therapy and was discharged home the following week. Use the following hyperlinks to read more information about treating pain: - Treating pain in Special Populations - The National Institute on Aging provides a wide range of information for older adults: Pain: You Can Get Help. - Health in Aging offers additional information on pain management at Pain Management \| Aging & Health AZ \| American Geriatrics Society. Trends in Pain Management, Substance Abuse, and Addiction Several well-known agencies have recently published materials focused on the importance of optimal pain management. For example, in 2017 The Joint Commission published new and revised standards of pain assessment and pain management that apply to all Joint Commission-accredited hospitals.The Joint Commission. (2017, August 29). R3 report \| Requirements, rationale, reference. https://www.jointcommission.org/-/media/tjc/documents/resources/patient-safety-topics/sentinel-event/r3_report_issue_11_pain_assessment_8_25_17_final.pdf?db=web&hash=938C24A464A5B8B5646C8E297C8936C1 The American Nurses Association published a position statement in 2018 on the ethical responsibility of nurses to properly manage pain.ANA Center for Ethics and Human Rights. (2018). Position statement: The ethical responsibility to manage pain and the suffering it causes. American Nurses Association. https://www.nursingworld.org/~495e9b/globalassets/docs/ana/ethics/theethicalresponsibilitytomanagepainandthesufferingitcauses2018.pdf In 2019 the U.S. Department of Health and Human Services published Pain Management Best Practices.Pain Management Best Practices Inter-Agency Task Force. (2019, May 9). Pain management best practices. U.S. Department of Health and Human Services. https://www.hhs.gov/sites/default/files/pmtf-final-report-2019-05-23.pdf Why is there continued emphasis on optimal pain management? Let’s review some trends related to pain management over the past few decades. Pain assessment and pain management began to undergo significant changes in the 1990s when pain experts recognized that inadequate assessment and treatment of pain had become a public health issue. Recommendations for improving the quality of pain care were followed by initiatives that recognized patients’ reported pain as “the 5th vital sign.” Hospital administrators and regulators began to focus on pain scores, encouraging and incentivizing providers to aggressively treat pain to lower pain scores. These trends led to liberal prescribing of opioid pain medications for both acute and chronic pain. Unfortunately, this increase in prescription of opioid pain medication led to an associated rise in the number of deaths from overdose. Organizations began to urge caution about the use of opioids for pain, including guidelines published in 2016 by the Centers for Disease Control (CDC) on prescribing opioids for pain.Cleveland Clinic. (2020, December 8). Acute v. chronic pain. https://my.clevelandclinic.org/health/articles/12051-acute-vs-chronic-pain The 2016 CDC guideline led to limited prescriptions of opioids and unintended consequences, such as forced tapering of medications for established patients requiring chronic pain control and the transition of some patients desperate for pain control to using illicit drugs, such as heroin. In this manner, pain management and the opioid crisis have influenced one another as each continues to evolve. It is imperative for nurses to ensure that patients with painful conditions can work with their health care providers to develop pain treatment plans that balance pain control, optimize function, and enhance quality of life while also minimizing risks for opioid misuse and harm.Pain Management Best Practices Inter-Agency Task Force. (2019, May 9). Pain management best practices. U.S. Department of Health and Human Services. https://www.hhs.gov/sites/default/files/pmtf-final-report-2019-05-23.pdf Associated Definitions When discussing the use and abuse of drugs used to treat pain, it is important to distinguish between tolerance, physical dependence, misuse, substance abuse disorder, and addiction. - Tolerance is a reduced response to pain medication when the same dose of a drug has been given repeatedly, requiring a higher dose of the drug to achieve the same level of response.Pain Management Best Practices Inter-Agency Task Force. (2019, May 9). Pain management best practices. U.S. Department of Health and Human Services. https://www.hhs.gov/sites/default/files/pmtf-final-report-2019-05-23.pdf/ For example, when a patient receives morphine for palliative care, the dosage often needs to be increased over time because the patient develops a tolerance to the effects of the medication. - Physical dependence refers to withdrawal symptoms that occur when a chronic pain medication is suddenly reduced or stopped because of physiological adaptations that occur to chronic exposure to the medication.Pain Management Best Practices Inter-Agency Task Force. (2019, May 9). Pain management best practices. U.S. Department of Health and Human Services. https://www.hhs.gov/sites/default/files/pmtf-final-report-2019-05-23.pdf For example, if a patient who receives hydromorphone daily suddenly has their prescription stopped, they will likely experience symptoms of withdrawal, such as sweating, goose bumps, vomiting, anxiety, insomnia, and muscle pain. - Misuse refers to a person taking prescription pain medications in a manner or dose other than prescribed; taking someone else’s prescription, even if for a medical complaint such as pain; or taking a medication to feel euphoria (i.e., to get high).Pain Management Best Practices Inter-Agency Task Force. (2019, May 9). Pain management best practices. U.S. Department of Health and Human Services. https://www.hhs.gov/sites/default/files/pmtf-final-report-2019-05-23.pdf - Substance abuse disorder is a significant impairment or distress from a pattern of substance use (i.e., alcohol, drugs, or prescription medication) with at least two of the symptoms listed below in a given year: - The use of more of a substance than planned or using a substance for a longer interval than desired - The inability to cut down despite desire to do so - Spending a substantial amount of the day obtaining, using, or recovering from substance use - Cravings or intense urge to use a substance - Repeated usage causing an inability to meet important social or professional obligations - Persistent usage despite user’s knowledge that it is causing frequent problems at work, school, or home - Giving up or cutting back on important social, professional, or leisure activities because of use - Usage in physically hazardous situations, such as driving, or usage despite it causing physical or mental harm - Persistent use despite the user’s awareness that the substance is causing, or at least worsening, a physical or mental problemAmerican Psychiatric Association. (2013). Diagnostic and statistical manual of mental disorders (5th ed.). https://doi.org/10.1176/appi.books.9780890425596 - Addiction is a chronic disease of the brain’s reward, motivation, memory, and related circuitry reflected in an individual pathologically pursuing reward and/or relief by substance use. Addiction is characterized by several symptoms, such as the inability to consistently abstain from a substance, impaired behavioral control, craving, diminished recognition of significant problems with one’s behaviors and interpersonal relationships, and a dysfunctional emotional response. Like other chronic diseases, addiction often involves cycles of relapse and remission. Without treatment or engagement in recovery activities, addiction is progressive and can result in disability or premature death.Pain Management Best Practices Inter-Agency Task Force. (2019, May 9). Pain management best practices. U.S. Department of Health and Human Services. https://www.hhs.gov/sites/default/files/pmtf-final-report-2019-05-23.pdf Substance Abuse Among Nurses and Nursing Students Substance abuse and addiction can occur in anyone, including nurses and nursing students. The American Nursing Association released the following statements in 2016: - Health care facilities should provide education to nurses and other employees regarding alcohol and other drug use and establish policies, procedures, and practices to promote safe, supportive, drug-free workplaces. - Health care facilities and schools of nursing should adopt alternative-to-discipline approaches to treating nurses and nursing students with substance use disorders, with stated goals of retention, rehabilitation, and reentry into safe, professional practice. - Drug diversion, in the context of personal use, is viewed primarily as a symptom of a serious and treatable disease, and not exclusively as a crime. - Nurses and nursing students are aware of the risks associated with substance use, impaired practice, and drug diversion and have the responsibility and means to report suspected or actual concerns.American Nurses Association. (2016, October). Substance use among nurses and nursing students. https://www.nursingworld.org/practice-policy/nursing-excellence/official-position-statements/id/substance-use-among-nurses-and-nursing-students Standards of Care Pain assessment and management standards were recently revised and published in 2018 by The Joint Commission. The revised standards require hospitals to identify pain assessment and pain management, including safe opioid prescribing, as an organizational priority. Nurses are expected to implement these best practices. See Table 11.2b for a summary of associated requirements that must be incorporated into nursing care.The Joint Commission. (2017, August 29). R3 report \| Requirements, rationale, reference. https://www.jointcommission.org/-/media/tjc/documents/resources/patient-safety-topics/sentinel-event/r3_report_issue_11_pain_assessment_8_25_17_final.pdf?db=web&hash=938C24A464A5B8B5646C8E297C8936C1 If these components are not included when providing nursing care, the hospital may be cited by The Joint Commission and potentially lose Medicare funding. Table 11.2b. The Joint Commission’s Pain Assessment and Management RequirementsThe Joint Commission. (2017, August 29). R3 report \| Requirements, rationale, reference. https://www.jointcommission.org/-/media/tjc/documents/resources/patient-safety-topics/sentinel-event/r3_report_issue_11_pain_assessment_8_25_17_final.pdf?db=web&hash=938C24A464A5B8B5646C8E297C8936C1 \| Requirement \| Rationale \| \|---\|---\| \| Patients are screened for pain during emergency department visits and at the time of admission. \| The misidentification and undertreatment of pain continues to occur in hospitals. When a patient presents to the hospital for other medical issues, pain may be overlooked or missed. Screening patients for pain or the risk of pain at the time of admission and while taking vital signs helps to improve pain identification and treatment. \| \| Criteria to screen, assess, and reassess pain are used that are consistent with the patient’s age, condition, and ability to understand. \| An accurate screening and assessment are required for satisfactory pain management, and the hospital is responsible for ensuring that appropriate screening and assessment tools are readily available and used appropriately. \| \| Patients are involved in the pain management treatment planning process by: – Collaboratively developing realistic expectations and measurable goals for the degree, duration, and reduction of pain – Discussing the criteria used to evaluate treatment progress (for example, relief of pain and improved physical and psychosocial function) – Receiving education on pain management, treatment options, and safe use of opioid and nonopioid medications when they are prescribed \| Patient involvement in planning pain management involves information sharing and collaboration between the patient and provider to arrive at realistic expectations and clear goals. Numerous patient factors may cause undertreatment or overtreatment of pain, such as pain expectations, knowledge of pain and its treatment, and underreporting of pain. Patient involvement in the pain management planning process allows the provider to clarify the objectives of the process and guides patients in a manner that increases the likelihood of treatment adherence. \| \| Patient’s pain is treated or they are referred for treatment. Treatment strategies for pain may include nonpharmacologic, pharmacologic, or a combination of approaches. \| Referrals may be required for patients who present with complex pain management needs, such as the opioid-addicted patient, the patient who is at high risk for adverse events but requires treatment with opioids, or a patient whose pain management needs exceed the expertise of the patient’s provider. \| \| Nonpharmacologic pain treatment modalities are promoted. \| Nonpharmacologic modalities should be promoted by ensuring that patient preferences are discussed and some nonpharmacologic treatment options provided. Nonpharmacologic strategies include, but are not limited to, physical modalities (e.g., acupuncture therapy, chiropractic therapy, osteopathic manipulative treatment, massage therapy, and physical therapy), relaxation therapy, and cognitive behavioral therapy. \| \| Patients identified as being high risk for adverse outcomes related to opioid treatment are monitored. \| The most dangerous adverse effect of opioid analgesics is respiratory depression. Equipment must be available to monitor patients deemed highest risk (e.g., patients with sleep apnea, those receiving continuous intravenous opioids, or those on supplemental oxygen). \| \| Patients experiencing opioid substance abuse are referred to opioid treatment programs. \| When clinicians encounter patients who are addicted to opioids, the patients should be referred for treatment. The U.S. Substance Abuse and Mental Health Services Administration provides a directory of opioid treatment programs. \| \| The hospital facilitates access to the Prescription Drug Monitoring Program databases. \| Prescription Drug Monitoring Programs (PDMP) aggregate prescribing and dispensing data submitted by pharmacies and health care providers. They are an effective tool for reducing prescription drug abuse and diversion. Read more about PDMP in the “Legal/Ethical” chapter of the Open RN Nursing Pharmacology textbook. \| \| Patient’s pain is reassessed and responded to through the following: Evaluation and documentation of: – Response to pain intervention(s) – Progress toward pain management goals including functional ability (for example, the ability to take a deep breath, turn in bed, walk with improved pain control) – Side effects of treatment \| Reassessment should be completed in a timely manner to determine if the intervention is working or if the patient is experiencing adverse effects. Only using numerical pain scales to monitor patients’ pain is inadequate. The Joint Commission’s technical advisory panel stressed the importance of assessing how pain affects function and the ability to make progress towards treatment goals. For example, immediately after major abdominal surgery, the goal of pain control may be the patient’s ability to take a breath without excessive pain. Over the next few days, the goal of pain control may be the ability to sit up in bed or walk to the bathroom without limitation due to pain. \| \| Patients and their family members are educated on discharge plans related to pain management including the following: – Pain management plan of care – Side effects of pain management treatment – Activities of daily living, including the home environment that might exacerbate pain or reduce effectiveness of the pain management plan of care, as well as strategies to address these issues – Safe use, storage, and disposal of opioids when prescribed \| During the discharge process, patients and families need education on the importance of how to manage the patient’s pain at home. Unmanaged pain may cause a patient to regress in their recovery process or have uncontrolled pain at home leading to a readmission to the hospital. It is necessary to have a discussion with patients and their families regarding their home environment and activities of daily living that may increase the need for pain management. When a patient is being discharged with an opioid medication, education on safe use, including when and how much medication to take, should be included in the discharge plan. Opioid disposal education is also critical to both reduce diversion and decrease the risk of accidental exposure to someone other than the person for whom the opioid was prescribed. \| Read Pain Management Best Practices from the United States Department of Health & Human Services. 11.3 Pain Assessment Methods Open Resources for Nursing (Open RN) Asking a patient to rate the severity of their pain on a scale from 0 to 10, with “0” being no pain and “10” being the worst pain imaginable is a common question used to screen patients for pain. However, according to The Joint Commission requirements described earlier, this question can be used to initially screen a patient for pain, but a thorough pain assessment is required. Additionally, the patient’s comfort-function goal must be assessed. The comfort-function goal provides the basis for the patient’s individualized pain treatment plan and is used to evaluate the effectiveness of interventions. PQRSTU, OLDCARTES, and COLDSPA The “PQRSTU,” “OLDCARTES,” or “COLDSPA” mnemonics are helpful in remembering a standardized set of questions used to gather additional data about a patient’s pain. See Figure 11.4This work is a derivative of The Complete Subjective Health Assessment by Lapum, St- Amant, Hughes, Petrie, Morrell, and Mistry and is licensed under CC BY-SA 4.0 for the questions associated with a “PQRSTU” assessment framework. While interviewing a patient about pain, use open-ended questions to allow the patient to elaborate on information that further improves your understanding of their concerns. If their answers do not seem to align, continue to ask focused questions to clarify information. For example, if a patient states that “the pain is tolerable” but also rates the pain as a “7” on a 0-10 pain scale, these answers do not align, and the nurse should continue to use follow-up questions using the PQRSTU framework. Upon further questioning the patient explains they rate the pain as a “7” in their knee when participating in physical therapy exercises, but currently feels the pain is tolerable while resting in bed. This additional information assists the nurse to customize interventions for effective treatment with reduced potential for overmedication with associated side effects. Sample questions when using the PQRSTU assessment are included in Table 11.3a. Table 11.3a. Sample PQRSTU Focused Questions for Pain \| PQRSTU \| Questions Related to Pain \| \|---\|---\| \| Provocation/Palliation \| What makes your pain worse? What makes your pain feel better? \| \| Quality \| What does the pain feel like? Note: You can provide suggestions for pain characteristics such as “aching,” “stabbing,” or “burning.” \| \| Region \| Where exactly do you feel the pain? Does it move around or radiate elsewhere? What were you doing when the pain started? Is the pain constant or does it come and go? If the pain is intermittent, when does it occur? How long does the pain last? Have you taken anything to help relieve the pain? \| \| Understanding \| What do you think is causing the pain? \| An alternative mnemonic to use when assessing pain is “OLDCARTES.” - Onset: When did the pain start? How long does it last? - Location: Where is the pain? - Duration: How long has the pain been going on? How long does an episode last? - Characteristics: What does the pain feel like? Can the pain be described in terms such as stabbing, gnawing, sharp, dull, aching, piercing, or crushing? - Aggravating factors: What brings on the pain? What makes the pain worse? Are there triggers such as movement, body position, activity, eating, or the environment? - Radiating: Does the pain travel to another area or the body, or does it stay in one place? - Treatment: What has been done to make the pain better and has it been helpful? Examples include medication, position change, rest, and application of hot or cold. - Severity: Rate your pain from 0 to 10. A third mnemonic used is “COLDSPA.” - C: Character - O: Onset - L: Location - D: Duration - S: Severity - P: Pattern - A: Associated Factors No matter which mnemonic is used to guide the assessment questions, the goal is to obtain comprehensive assessment data that allows the nurse to create a customized nursing care plan that effectively addresses the patient’s need for comfort. Pain Scales In addition to using the PQRSTU or OLDCARTES methods of investigating a patient’s chief complaint, there are several standardized pain rating scales used in nursing practice. FACES Scale The FACES scale is a visual tool for assessing pain with children and others who cannot quantify the severity of their pain on a scale of 0 to 10. See Figure 11.5Wong-Baker FACES Foundation. (2016). Wong-Baker FACES pain rating scale. https://wongbakerfaces.org/. Used with permission. for the FACES Pain Rating Scale. To use this scale, use the following evidence-based instructions. Explain to the patient that each face represents a person who has no pain (hurt), some pain, or a lot of pain. “Face 0 doesn’t hurt at all. Face 2 hurts just a little. Face 4 hurts a little more. Face 6 hurts even more. Face 8 hurts a whole lot. Face 10 hurts as much as you can imagine, although you don’t have to be crying to have this worst pain.” Ask the person to choose the face that best represents the pain they are feeling.Wong-Baker FACES Foundation. (2016). Wong-Baker FACES pain rating scale. https://wongbakerfaces.org/. Used with permission. FLACC Scale The FLACC scale (i.e., the Face, Legs, Activity, Cry, Consolability scale) is a measurement used to assess pain for children between the ages of 2 months and 7 years or individuals who are unable to verbally communicate their pain. The scale has five criteria, which are each assigned a score of 0, 1, or 2. The scale is scored in a range of 0–10 with “0” representing no pain.Merkel, S. I., Voepel-Lewis, T., Shayevitz, J. R., & Malviya, S. (1997). The FLACC: A behavioral scale for scoring postoperative pain in young children. Pediatric Nursing, 23(3). https://pubmed.ncbi.nlm.nih.gov/9220806/ See Table 11.3b for the FLACC scale. Table 11.3b The FLACC ScaleMerkel, S. I., Voepel-Lewis, T., Shayevitz, J. R., & Malviya, S. (1997). The FLACC: A behavioral scale for scoring postoperative pain in young children. Pediatric Nursing, 23(3). https://pubmed.ncbi.nlm.nih.gov/9220806/ \| Criteria \| Score 0 \| Score 1 \| Score 2 \| \|---\|---\|---\|---\| \| Face \| No particular expression or smile \| Occasional grimace or frown, withdrawn, or uninterested \| Frequent to constant quivering chin; clenched jaw \| \| Legs \| Normal position or relaxed \| Uneasy, restless, or tense \| Kicking or legs drawn up \| \| Activity \| Lying quietly, normal position, and moves easily \| Squirming, shifting, back and forth, or tense \| Arched, rigid, or jerking \| \| Cry \| No cry (awake or asleep) \| Moans or whimpers or occasional complaint \| Crying steadily, screams or sobs, or frequent complaints \| \| Consolability \| Content and relaxed \| Reassured by occasional touching, hugging, or being talked to; distractible \| Difficult to console or comfort \| COMFORT Behavioral Scale The COMFORT Behavioral Scale is a behavioral-observation tool validated for use in children of all ages who are receiving mechanical ventilation. Eight physiological and behavioral indicators are scored on a scale of 1 to 5 to assess pain and sedation.Freund, D., & Bolick, B. (2019). CE: Assessing a Child’s Pain. American Journal of Nursing. 119(5), 34. https://journals.lww.com/ajnonline/Fulltext/2019/05000/CE__Assessing_a_Child_s_Pain.25.aspx Pain Assessment in Advanced Dementia (PAINAD) Scale The Pain Assessment in Advanced Dementia (PAINAD) Scale is a simple, valid, and reliable instrument for assessing pain in noncommunicative patients with advanced dementia. See Table 11.3c for the items included on the scale. Each item is scored from 0-2, When totaled, the score can range from 0 (no pain) to 10 (severe pain). Table 11.3c The PAINAD ScaleWarden V., Hurley A., & Volicer, L. (2003). Development and psychometric evaluation of the pain assessment in advanced dementia (PAINAD) scale. Journal of the American Medical Directors Association, 4(1), 9-15. https://doi.org/10.1097/01.JAM.0000043422.31640.F7 \| Item \| 0 \| 1 \| 2 \| \| Breathing independent of vocalization \| Normal \| Occasional labored breathing. Short period of hyperventilation. \| Noisy labored breathing. Long period of hyperventilation. Cheyne-Stokes respirations. \| \| Negative vocalization \| None \| Occasional moan or groan. Low-level speech with a negative or disapproving quality. \| Repeated troubled calling out. Loud moaning or groaning. Crying. \| \| Facial Expression \| Smiling or inexpressive \| Sad. Frightened. Frown. \| Facial grimacing. \| \| Body language \| Relaxed \| Tense. Distressed pacing. Fidgeting. \| Rigid. Fists clenched. Knees pulled up. Pulling or pushing away. Striking out. \| \| Consolability \| No need to console \| Distracted or reassured by voice or touch. \| Unable to console, distract, or reassure. \| Comfort-Function Goals Comfort-function goals encourage the patient to establish their level of comfort needed to achieve functional goals based on their current health status. For example, one patient may be comfortable ambulating after surgery and their pain level is 3 on a 0-to-10 pain intensity rating scale, whereas another patient desires a pain level of 0 on a 0-to-10 scale in order to feel comfortable ambulating. To properly establish a patient’s comfort-function goal, nurses must first describe the essential activities of recovery and explain the link between pain control and positive outcomes.Boswell, C., & Hall, M. (2017). Engaging the patient through comfort-function levels. Nursing 2017, 47 (10), 68-69. https://www.nursingcenter.com/journalarticle?Article_ID=4345712&Journal_ID=54016&Issue_ID=4345459 If a patient’s pain score exceeds their comfort-function goal, nurses must implement an intervention and follow up within 1 hour to ensure that the intervention was successful. Using the previous example, if a patient had established a comfort-function goal of 3 to ambulate and the current pain rating was 6, the nurse would provide appropriate interventions, such as medication, application of cold packs, or relaxation measures. Documentation of the comfort-function goal, pain level, interventions, and follow-up are key to effective, individualized pain management.Boswell, C., & Hall, M. (2017). Engaging the patient through comfort-function levels. Nursing 2017, 47 (10), 68-69. https://www.nursingcenter.com/journalarticle?Article_ID=4345712&Journal_ID=54016&Issue_ID=4345459 11.4 Pain Management Open Resources for Nursing (Open RN) Pain management requires collaboration with the interdisciplinary team, including nurses, health care providers, pharmacists, and sometimes pain specialists. There are many different types of pain medications (called analgesics) that can be administered by various routes. Analgesics are classified as nonopioids, opioids, or adjuvants. An adjuvant is a medication that has been found in clinical practice to have either an independent analgesic effect or additive analgesic properties when administered with opioids. Examples of adjuvant medications include antidepressants (e.g., amitriptyline) and anti-seizure medications (e.g., gabapentin). A general rule of thumb when administering analgesics is to use the lowest dose of medication, with fewest potential side effects and the least invasive route of administration, to effectively treat the level of pain as reported by the patient. The WHO ladder was originally developed by the World Health Organization for selecting analgesics for patients with cancer pain, but it can be broadened to illustrate this rule of thumb for managing pain appropriately for all patients. See Figure 11.6World Health Organization. (1996). Cancer pain relief (2nd ed.). http://apps.who.int/iris/bitstream/handle/10665/37896/9241544821.pdf;jsessionid=08444506DC35A33288AD7C0DE6D34667?sequence=1 for an image of the WHO ladder. For example, if a patient reports a pain level of “2,” then a nurse typically starts at the lowest rung of the WHO ladder and administers a prescribed nonopioid via the oral route. If the nonopioid is not effective, then a prescribed adjuvant medication may be administered, or the nurse may decide to step up a rung on the ladder and administer a prescribed oral opioid for mild to moderate pain. On the other hand, if a patient reports severe pain, the nurse may start at the top rung of the ladder and administer a prescribed opioid for moderate to severe pain via the intravenous route for rapid relief. Nonopioid Analgesics Nonopioid analgesics include acetaminophen and NSAIDs. Acetaminophen Acetaminophen (Tylenol) is used to treat mild pain and fever but does not have anti-inflammatory properties. Acetaminophen is safe for all ages and can be administered using various routes, such as orally, rectally, and intravenously. Many over-the-counter (OTC) medications contain acetaminophen, along with other medications. See Figure 11.7“Extra_Strength_Tylenol_and_Tylenol_PM.jpg” by Ragesoss is licensed under CC BY-SA 4.0 for an image of acetaminophen (Tylenol) and acetaminophen and diphenhydramine (Tylenol PM). A potential severe side effect of acetaminophen is hepatotoxicity (severe liver damage). Severe liver damage may occur if an adult patient takes more than 4,000 mg of acetaminophen in 24 hours (or 3,200 mg for older adults or 2,000 mg for chronic alcoholics) or consumes three or more alcoholic drinks every day while using acetaminophen. Because some medications are combined with acetaminophen or are prescribed “as needed,” the nurse must calculate the cumulative dose of acetaminophen over the previous 24-hour period before administering an additional dose. For example, Percocet 5/325 contains a combination of oxycodone 5 mg and acetaminophen 325 mg and may be prescribed as “1-2 tablets every 4-6 hours as needed for pain.” If two tablets are truly administered every four hours over a 24-hour period, this would add up to 3,900 mg of acetaminophen, exceeding the recommended guidelines for a geriatric patient, with the potential for causing liver damage. NSAIDs Nonsteroidal anti-inflammatories (NSAIDs) provide mild to moderate pain relief and also reduce fever and inflammation by inhibiting the production of prostaglandins. They can also be used as an adjuvant with opioids for severe pain. Examples of NSAIDs include ibuprofen, naproxen, and ketorolac. All NSAIDs, except aspirin, increase the risk of heart attack, heart failure, and stroke, with the risk being higher if the patient takes more than is directed or takes it for longer than directed. Common side effects include dyspepsia, nausea, and vomiting, so it is helpful to administer this medication with food. Older adults and those taking NSAIDs concurrently with other drugs, such as warfarin or corticosteroids, are at elevated risk for gastrointestinal bleeding. Renal failure can also occur with NSAIDs. - Ibuprofen (Motrin) is safe for infants 6 months or older. It is typically prescribed every 6 to 8 hours. - Naproxen (Naprosyn) is longer-acting than ibuprofen and is typically prescribed 2 or 3 times a day with a full glass of water. - Ketorolac (Toradol) is commonly used to treat “breakthrough” pain that occurs during the treatment of severe acute pain already being treated with opioids. It is indicated for the short-term management (up to 5 days in adults) of moderate to severe acute pain that requires analgesia at the opioid level. Ketorolac is safe for adults, but the dosage should be reduced for patients ages 65 and over. View a supplementary video on “How Do Pain Relievers Work?“ Opioid Analgesics Opioids are used to treat moderate to severe pain and work by blocking the release of neurotransmitters involved in the processing of pain. Different opioids have different amounts of analgesia, ranging from codeine used to treat mild to moderate pain, up to morphine, used to treat severe pain and considered to be at the top of the WHO ladder. See Table 11.4a for a summary of common opioids. As always, check a drug reference for current dosage ranges before administering medications. Table 11.4a Common Opioid Analgesics \| Generic Name \| Trade Name(s) \| Route \| Adult Dosages \| \|---\|---\|---\|---\| \| Codeine with acetaminophen \| Tylenol #3 \| PO \| 30 mg/300 mg \| \| Hydrocodone with acetaminophen \| Lortab, Norco, Vicodin \| PO \| 5 mg/300 mg or 325 mg 10 mg/320 mg or 325 mg 5mg/500 mg \| \| Oxycodone (immediate release and extended release) OR Oxycodone with acetaminophen \| Oxycodone IR & OxyContin (ER) Percocet & Roxicet \| PO PO \| 5 mg – 10 mg 5 mg/325 mg \| \| Fentanyl \| Duragesic, Sublimaze \| Transdermal IM IV \| 12 mcg – 100 mcg/hr 0.5 – 1 mcg/kg 0.5 – 1 mcg/kg \| \| Hydromorphone \| Dilaudid \| PO Rectal SubQ, IM, & IV \| 4 – 8 mg 3 mg 1.5 mg (may be increased) \| \| Morphine \| Duramorph, MS Contin, Oramorph SR, & Roxanol \| PO & Rectal SubQ, IM, & IV \| 30 mg (may be increased) 4 – 10 mg (may be increased) \| Morphine is also commonly used to treat cancer pain and end-of-life pain because there is no “ceiling effect,” meaning the higher the dose, the higher the level of analgesia. Morphine is administered via various routes of administration, including orally, rectally, subcutaneously, intramuscularly, and intravenously. See Figure 11.8“Morphine_vial.JPG” by Vaprotan is licensed under CC BY-SA 3.0 for an image of a vial of morphine for injection or intravenous use. Other types of opioids can be administered through the skin, such as the fentanyl transdermal patch. See Figure 11.9“Fentanyl_Transdermal_System_50_mcg_Patch.jpg” by User:Crohnie is licensed under CC BY-SA 3.0 for an image of a fentanyl transdermal patch. Alternative Routes of Administration of Opioids Analgesic medications can be administered via several routes, including orally, rectally, subcutaneously, and intravenously. Intramuscular routes are typically avoided. Other routes of administration include patient-controlled analgesia (PCA), intrathecally, and by epidural. Patient Controlled Analgesia Patient-controlled analgesia (PCA) is a method of pain management that allows hospitalized patients with severe pain to safely self-administer opioid medications using a programmed pump according to their level of discomfort. See Figure 11.10“PCA-01.JPG” by DiverDave is licensed under CC BY-SA 3.0 for an image of a PCA pump. A computerized pump contains a syringe of pain medication and is connected directly to a patient’s intravenous (IV) line. Pain medication includes morphine, hydromorphone, and fentanyl. Doses of medication can be self-administered as needed by the patient by pressing a button. However, the pump is programmed to only allow administration of medication every set number of minutes with a maximum dose of medication every hour. These pump settings, and the design of the system requiring the patient to be alert enough to press the button, are safety measures to prevent overmedication that can cause sedation and respiratory depression. For this reason, no one but the patient should press the button for administration of medication (not even the nurse.) In other cases, the PCA pump delivers a small, continuous flow of pain medication intravenously with the option of the patient self-delivering additional medication as needed, according to the limits set on the pump. To document the amount and frequency of pain medication the patient is receiving, as well as to prevent drug diversion, the settings on the pump are checked at the end of every shift as part of the bedside report. The incoming and outgoing nurses double-check and document the pump settings, the amount of medication administered during the previous shift, and the amount of medication left in the syringe. Intrathecal Pump Another type of pump used to deliver pain medication is the intrathecal pump. This pump is surgically implanted under the skin and delivers small quantities of pain medication, such as morphine, directly into the spinal fluid. It is used to treat pain and muscle spasticity when other methods have not effectively treated the pain. It is typically used for patients with severe chronic pain, such as cancer pain, back pain, or nerve pain. However, the FDA urges cautious use because it has received numerous Medical Device Reports (MDRs) describing adverse events with implanted pumps. These reports describe pump failures, dosing errors, and other potential safety issues. Patient symptoms described in these reports include pain, opioid withdrawal, fever, vomiting, muscle spasm, cognitive changes, weakness, and cardiac and respiratory distress.U.S. Food & Drug Administration. (2018, November 14). Use caution with implanted pumps for intrathecal administration of medicines for pain management: FDA safety communication. https://www.fda.gov/medical-devices/safety-communications/use-caution-implanted-pumps-intrathecal-administration-medicines-pain-management-fda-safety Epidural A third route of alternative administration of pain medication is epidural anesthesia. See Figure 11.11“Epidural_Anesthesia.png” by BruceBlaus is licensed under CC BY-SA 4.0 for an image of an epidural anesthesia. Morphine is administered into the spinal fluid via an epidural catheter for severe pain management associated with surgical procedures or during labor and delivery. It is also used to treat chronic pain that has not responded to other treatments. Epidural administration of 5 mg of morphine provides adequate postoperative analgesia for up to 24 hours.This work is a derivative of StatPearls by Martinez-Velez and Singh and is licensed under CC BY 4.0 Adverse Effects of Opioids Respiratory Depression The most serious potential adverse effect of opioids is respiratory depression. Respiratory depression is usually preceded by sedation. The nurse must carefully monitor patients receiving opioids for oversedation, which results in decreased respiratory rate. Patients at greatest risk are those who have never received an opioid and are receiving their first dose, those receiving an increased dose of opioids, or those taking benzodiazepines or other sedatives concurrently with opioids. If a patient develops opioid-induced respiratory depression, the opioid is reversed with naloxone (Narcan) that immediately reverses all analgesic effect.American Association of Colleges of Nursing. (n.d.). End-of-Life-Care (ELNEC). https://www.aacnnursing.org/ELNEC See Figure 11.12“Opiod_Rescue_Kit_3.jpg” by Intropin (Mark Oniffrey) is licensed under CC BY_SA 4.0 for an image of a naloxone rescue kit to treat respiratory depression caused by opioids. Opioids can cause several other common adverse effects, such as constipation, nausea and vomiting, urinary retention, and pruritus (itching). Constipation Opioids slow peristalsis and cause increased reabsorption of fluid into the large intestine, resulting in slow-moving, hard stools. Nurses play an important role in preventing constipation for all patients taking opioids. A bowel management program should be initiated with the first dose and continued until the opioid is discontinued. A stool softener (such as docusate) is typically prescribed initially as part of the bowel management program. If needed, a stimulant laxative, such as sennoside (Senna), bisacodyl, or Milk of Magnesia may be added to maintain a normal bowel pattern. However, stimulants should not be taken long-term because they can be addictive. Patients taking opioids should be encouraged to increase fluid and fiber intake and ambulate, as appropriate.American Association of Colleges of Nursing. (n.d.). End-of-Life-Care (ELNEC). https://www.aacnnursing.org/ELNEC Nausea and Vomiting Nausea and vomiting can occur with opioid administration due to several factors, such as the slowing of gastrointestinal mobility, constipation, or stimulation of the vestibular system. Tolerance will develop to these adverse effects within a few days. Treatment includes antiemetics, such as compazine or ondansetron.American Association of Colleges of Nursing. (n.d.). End-of-Life-Care (ELNEC). https://www.aacnnursing.org/ELNEC Urinary Retention Urinary retention is common in opioid-naive patients or when opioids are delivered via the spinal route. Urinary catheterization may be required if the patient is unable to void. Tolerance to this effect occurs within a few days.American Association of Colleges of Nursing. (n.d.). End-of-Life-Care (ELNEC). https://www.aacnnursing.org/ELNEC Pruritus Pruritus (itching) may occur, especially when opioids are administered via the spinal route. Antihistamines, such as diphenhydramine (Benadryl), may be used to treat pruritus, but the patient should be monitored for potential sedative effects of this medication.American Association of Colleges of Nursing. (n.d.). End-of-Life-Care (ELNEC). https://www.aacnnursing.org/ELNEC Adjuvant Medications Adjuvants are medications that are not classified as analgesics but have been found to contribute to analgesic effects, especially when used in addition to opioids. Two common examples of adjuvant medications are amitriptyline and gabapentin. Amitriptyline Amitriptyline is a tricyclic antidepressant that is also believed to be effective in treating neuropathic pain, such as diabetic neuropathy, postherpetic neuralgia, or post‐stroke pain. The mechanism of action of amitriptyline in the treatment of neuropathic pain remains uncertain, although it is known to inhibit both serotonin and noradrenaline reuptake. It is usually administered at bedtime in an attempt to reduce any sedative effects during the day.Moore, R. A., Derry, S., Aldington, D., Cole, P., & Wiffen, P. J. (2015). Amitriptyline for neuropathic pain in adults. The Cochrane Database of Systematic Reviews, 2015(7). https://doi.org/10.1002/14651858.CD008242.pub3 Gabapentin Gabapentin is an anticonvulsant that is also effective in treating neuropathic pain and restless leg syndrome. Patients taking gabapentin should be warned that their mental health may change in unexpected ways or they may become suicidal. Nurses should implement fall precautions for patients taking gabapentin because it can cause sleepiness, weakness, and unsteadiness.MedlinePlus [Internet]. Bethesda (MD): National Library of Medicine (US); Gabapentin; [updated 2021, Jan 22; reviewed 2020, May 15; cited 2021, Feb 16]. https://medlineplus.gov/druginfo/meds/a694007.html Nonpharmacological Interventions Nonpharmacological interventions can be used with or without pharmacologic interventions and often provide tremendous benefits to the patient. A variety of techniques can be selected by the patient that best fit their needs and goals. Nonpharmacological interventions should be documented in the plan of care and their effectiveness evaluated in terms of their ability to meet the patient’s goals for pain relief. Table 11.4b provides examples of several types of nonpharmacological interventions. Table 11.4b Nonpharmacological Interventions \| Intervention \| Examples \| \|---\|---\| \| Distraction \| Describing photos, telling jokes, and playing games \| \| Relaxation \| Rhythmic breathing, meditation, prayer, imagery, and music therapy \| \| Basic comfort measures \| Proper positioning and therapeutic environment Avoiding sudden movement Reducing pain stimuli within the environment \| \| Cutaneous stimulation \| Acupuncture and acupressure Massage: 3-5 minutes offers benefits Transcutaneous Electrical Nerve Stimulation (TENS) unit: a specialized stimulator placed over the area of pain \| \| Application of heat or cold \| Heat: vasodilation increases blood flow; duration should be 5-20 minutes based on patient tolerance Cold: vasoconstriction reduces blood flow; cold numbs nerve sensations; duration should be no longer than 20 minutes Cool baths and moist, cool compresses \| \| Mind-body therapies \| Biofeedback Meditation and mindfulness \| \| Aromatherapy \| Lotions and moisturizing cream Avoiding strong smells \| \| Exercise \| Physical activity Tai chi Yoga \| \| Therapy \| Physical therapy Occupational therapy \| See Figure 11.13“Massage-hand-4.jpg” by Lubyanka is licensed under CC BY-SA 3.0, “Biofeedback_training_program_for_post-traumatic_stress_symptoms.jpg” by Army Medicine is licensed under CC BY 2.0, “Tai_Chi1.jpg” by Craig Nagy is licensed under CC BY-SA 2.0, “Musicoterapia_lmidiman_flickr.jpg” by Midiman is licensed under CC BY 2.0, “Cold_Hot_Pack.jpg” by Mamun2a is licensed under CC BY-SA 4.0, “pexels-photo-1188511.jpeg” by Mareefe is licensed under CC0, “STOTT-PILATES-reformer-class.jpg” by MHandF is licensed under CC BY-SA 3.0, “prayer-2544994_960_720.jpg” by Himsan is licensed under CC0, “gaming-2259191_960_720.jpg” by JESHOOTS-com is licensed under CC0 for images of various nonpharmacological interventions. Patients may also consider using complementary health approaches to manage chronic pain. Complementary approaches include acupuncture, massage therapy, meditation, relaxation techniques, spinal manipulation, Tai Chi, yoga, and dietary supplements. Read more about complementary approaches using the hyperlink provided in the following box. Read more about complementary approaches to treat pain from the National Center for Complementary and Integrative Health. Read about pain management for older adults from the University of Iowa. 11.5 Applying the Nursing Process Open Resources for Nursing (Open RN) Assessment Nurses play an essential role in performing comprehensive pain assessment. Assessments include asking questions about the presence of pain, as well as observing for nonverbal indicators of pain, such as grimacing, moaning, and touching the painful area. It is especially important to observe for nonverbal indicators of pain in patients unable to self-report their pain, such as infants, children, patients who have a cognitive disorder, patients at end of life, non-English speaking patients, or patients who tend to be stoic due to cultural beliefs. See Figure 11.14“238074231_2485ed053b_o” by Erik Ogan is licensed under CC BY-SA 2.0 for an image of a patient who is expressing pain nonverbally. Recall that pain is defined as whatever the person experiencing it says it is. Subjective assessment includes asking questions regarding the severity rating, as well as obtaining comprehensive information by using the “PQRSTU” or “OLDCARTES” methods for assessing a chief complaint. For some patients who are unable to quantify the severity of their pain, a visual scale like the FACES scale is the best way to perform subjective assessment regarding the severity of pain. Objective data includes observations of nonverbal indications of pain, such as restlessness, facial grimacing and wincing, moaning, and rubbing or guarding painful areas. For patients who cannot verbalize their pain, using a scale like the FLACC, COMFORT, or PAINAD is helpful to standardize observations across different staff members. Keep in mind that patients experiencing acute pain will also likely have vital signs changes, such as increased blood pressure, increased heart rate, and increased respiratory rate. It is important to assess the impact of pain on a patient’s daily functioning. This can be accomplished by asking what effect the pain has on their ability to bathe, dress, prepare food, eat, walk, and complete other daily activities. Assessing the impact of pain on daily functioning is a new standard of care that assists the interdisciplinary team in tailoring treatment goals and interventions that are customized to the patient’s situation. For example, for some patients, chronic pain affects their ability to be employed, so effective pain management is vital so they can return to work. For other patients receiving palliative care, the ability to sit up and eat a meal with loved ones without pain is an important goal.American Association of Colleges of Nursing. (n.d.). End-of-Life-Care (ELNEC). https://www.aacnnursing.org/ELNEC When performing a patient assessment, any new complaints of pain or pain that is unresponsive to the current treatment plan should be reported to the health care provider. Instances of sudden, severe pain or chest pain require immediate notification or contact of emergency services. Diagnoses Commonly used NANDA-I nursing diagnoses for pain include Acute Pain (duration less than 3 months) and Chronic Pain. See Table 11.5 for more information regarding these diagnoses.Herdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers, New York, pp. 445-446. For more information about defining characteristics and related factors for other NANDA-I nursing diagnoses, refer to a current nursing diagnosis resource. Table 11.5 Pain NANDA-I Nursing DiagnosesHerdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers, New York, pp. 445-446. \| NANDA-I Diagnosis \| Definition \| Defining Characteristics \| \|---\|---\|---\| \| Acute Pain \| Unpleasant sensory and emotional experience associated with acute or potential tissue damage, or described in terms of such damage; sudden or slow onset of any intensity from mild to severe with an anticipated or predictable end, and with a duration of less than 3 months. \| \| \| Chronic Pain \| Unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage (International Association for the Study of Pain); sudden or slow onset of any intensity from mild to severe, constant or recurring without anticipated or predictable end, and with a duration of greater than 3 months. \| \| Outcome Identification An overall goal when providing pain management is, “The patient will report that the pain management treatment plan achieves their comfort-function goals.”Ackley, B., Ladwig, G., Makic, M. B., Martinez-Kratz, M., & Zanotti, M. (2020). Nursing diagnosis handbook: An evidence-based guide to planning care (12th ed.). Elsevier, pp. 676-691. SMART outcomes are customized to the patient’s unique situation. An example of a SMART goal is, “The patient will notify the nurse promptly for pain intensity level that is greater than their comfort-function goal throughout shift.”Ackley, B., Ladwig, G., Makic, M. B., Martinez-Kratz, M., & Zanotti, M. (2020). Nursing diagnosis handbook: An evidence-based guide to planning care (12th ed.). Elsevier, pp. 676-691. Planning Interventions Several pharmacological and nonpharmacological interventions have been described throughout this chapter. See the following box for a summarized list of interventions for acute pain management. Acute Pain ManagementButcher, H., Bulechek, G., Dochterman, J., & Wagner, C. (2018). Nursing Interventions Classification (NIC). Elsevier, pp. 281-282. - Identify pain intensity during required recovery activities (e.g., coughing and deep breathing, ambulation, transfers to chair, etc.) - Explore patient’s knowledge and beliefs about pain, including cultural influences - Question patient regarding the level of pain that allows a state of comfort and desired function and attempt to keep pain at or lower than identified level - Ensure that the patient receives prompt analgesic care before the pain becomes severe or before pain-inducing activities - Administer analgesics around-the-clock as needed the first 24 to 48 hours after surgery, trauma, or injury except if sedation or respiratory status indicates otherwise - Monitor sedation and respiratory status before administering opioids and at regular intervals when opioids are administered - Follow agency protocols in selecting analgesia and dosage - Use a combination of prescribed medications (e.g., opioids, nonopioids, and adjuvants), if pain level is severe - Select and implement interventions tailored to the patient’s risks, benefits, and preferences (e.g., pharmacological and nonpharmacological) to facilitate pain relief - Cautiously use analgesics that may have adverse effects in older adults - Administer analgesics using the least invasive route available, avoiding the intramuscular route - Advocate PCA, intrathecal, and epidural routes of administration when appropriate - Modify pain control measures on the basis of the patient’s response to treatment - Prevent and/or manage medication side effects - Notify prescribing provider if pain control measures are unsuccessful - Provide accurate information to family members or caregivers about the patient’s pain experience with the patient’s permission See the following box for a summarized list of interventions for chronic pain management. Chronic Pain ManagementButcher, H., Bulechek, G., Dochterman, J., & Wagner, C. (2018). Nursing Interventions Classification (NIC). Elsevier, pp. 281-282. - Explore the patient’s knowledge and beliefs about pain, including cultural influences - Determine the pain experience on quality of life (e.g., sleep, appetite, activity, cognition, mood, relationships, job performance, and role responsibilities) - Evaluate the effectiveness of past pain control measures with the patient - Question the patient regarding the level of pain that allows a state of comfort and appropriate functioning and attempt to keep pain at or lower than identified level - Control environmental factors that may influence the patient’s pain experience - Ensure that the patient receives prompt analgesic care before the pain becomes severe or before activities that are anticipated to be pain-inducing - Select and implement intervention options tailored to the patient’s risks, benefits, and preferences (e.g., pharmacological, nonpharmacological, interpersonal) to facilitate pain relief, as appropriate - Instruct the patient and family about principles of pain management - Encourage the patient to monitor own pain and to use self-management approaches - Encourage appropriate use of nonpharmacological techniques (e.g., biofeedback, TENS, hypnosis, relaxation, guided imagery, music therapy, distraction, play therapy, activity therapy, acupressure, heat and cold application, and massage) and pharmacological options as pain control measures - Avoid use of analgesics that may have adverse effects on older adults - Collaborate with the patient, family, and other health professionals to select and implement pain control measures - Prevent or manage side effects - Evaluate the effectiveness of pain control measures through ongoing monitoring of the pain experience - Watch for signs of depression (e.g., sleeplessness, not eating, flat affect, statements of depression, or suicidal ideation) - Watch for signs of anxiety or fear (e.g., irritability, tension, worry, or fear of movement) - Modify pain control measures on the basis of the patient’s response to treatment - Incorporate the family in the pain relief modality, when possible - Utilize a multidisciplinary approach to pain management, when appropriate - Consider referrals for the patient and family to support groups and other resources, as appropriate - Evaluate patient satisfaction with pain management at specified intervals - Evaluate barriers to adherence with past pain management care plans Implementing Pharmacological Interventions Patients should be involved and engaged in their plan of care to treat pain. By demonstrating empathy and collaborating with patients and the interdisciplinary team, it is more likely the treatment plan will be effective based on the patient’s goals. When administering analgesic medication, holistic nursing care is important. Begin by considering the patient’s goals for pain relief and ask if they have been met effectively by previously administered medications. If they have not been met, it may be necessary to advocate for additional or alternative medication with the health care provider. It is also important to consider if the patient is experiencing any side effects that may impact the patient’s desire to take additional pain medication. When administering medications that have been ordered on an “as-needed” basis, it is vital for the nurse to verify the amount of medication the patient received in the past 24 hours and if any dosage limits have been met to ensure patient safety. Prior to administration, consider the best route of administration for this patient at this particular time. For example, if the patient is nauseated and vomiting, then an oral route may not be effective. On the other hand, if a patient’s pain has improved when receiving intravenous medications during the recovery process, it may be possible for the patient to begin taking oral pain medications in preparation for discharge home. Keep the WHO ladder in mind when selecting medications to reach patient goals while also avoiding potential adverse effects when possible. When preparing opioid medications, it is important to remember that these medications are controlled substances with special regulations regarding storage, count auditing, and disposal/wasting of medication. Follow agency policy regarding these issues. It is also important to assess the patient’s level of sedation and respiratory status before administering additional doses of opioids and withhold the medication if the patient is oversedated or their respiratory rate is less than 12/minute. However, when providing pain management during end-of-life care, these parameters no longer apply because the emphasis is on providing comfort according to the patient’s preferences. Read more about end-of-life care in the “Grief and Loss” chapter. Evaluation It is vital for the nurse to regularly evaluate if the established interventions are effectively meeting the pain management and function goals established collaboratively with the patient. Additionally, when administering analgesics, the patient should be reassessed in an hour (or other time frame based on the onset and peak of the medication) to determine if the medication was effective. If interventions are not effective, then follow-up interventions are required, which may include contacting the health care provider. For patients living with chronic pain, it can be helpful for them or their caregiver to maintain a pain journal. In the journal they can document activities that precipitated pain, medications taken to manage the pain, and whether these medications were effective in helping them to meet their functional goals. This journal is shared with the health care provider during follow-up visits to enhance the treatment plan.American Association of Colleges of Nursing. (n.d.). End-of-Life-Care (ELNEC). https://www.aacnnursing.org/ELNEC The nurse must continually monitor for potential adverse effects of pain medications. For example, if a patient is receiving acetaminophen daily for chronic osteoarthritis pain, signs of liver dysfunction, such as jaundice and elevated liver function bloodwork, should be monitored. For older adults receiving NSAIDs, it is important to watch for early signs of gastrointestinal bleeding, such as melena. Patients receiving opioids should be continually monitored for oversedation, respiratory depression, constipation, nausea and vomiting, urinary retention, and pruritus. Side effects should be reported to the health care provider and orders received for treatment. 11.6 Putting It All Together Patient Scenario Mrs. Jamison is a 34-year-old woman admitted through the emergency department with kidney stones. As you reposition her in bed, she is visibly grimacing and audibly moaning. You recheck her vital signs and her blood pressure is elevated at 150/90 and her heart rate is 120. Applying the Nursing Process Assessment: The nurse notes that Mrs. Jamison demonstrates signs of discomfort with visible grimacing, audible moaning, and elevated blood pressure and heart rate. She rates her pain at “8 out of 10.” Based on the assessment information that has been gathered, the following nursing care plan is created for Mrs. Jamison. Nursing Diagnosis: Acute Pain related to physical injury agent as evidenced by change in physiological parameters and self-report of pain rated as “8 out of 10.” Overall Goal: The patient will report that the pain management treatment plan achieves her comfort-function goal. SMART Expected Outcomes: - Mrs. Jamison will verbalize pain reduction to a self-reported tolerable level of “4” or less on a 0-10 scale by the end of the shift. - Mrs. Jamison’s blood pressure and heart rate will return to baseline levels by the end of the shift. Planning and Implementing Nursing Interventions: The nurse will perform a comprehensive pain assessment and identify the patient’s expectation regarding pain management. The nurse will encourage the patient to use breathing techniques and relaxation methods to facilitate pain management. The nurse will notify the provider of unrelieved pain and request additional prescriptions for medication as needed. Sample Documentation: Mrs. Jamison was admitted with acute pain related to kidney stones and is receiving Morphine via PCA pump. At 1400, her blood pressure was elevated at 150/90 and her heart rate elevated at 120. She reported pain as an “8 out of 10.” She was visibly grimacing and audibly moaning when repositioned in bed. Dr. Smith was notified at 1400 and a new prescription received. Ketorolac 30 mg IV was administered at 1415. At 1515, the patient stated her pain had decreased to a “3 out of 10” level and this level was “satisfactory.” Her blood pressure also decreased to 135/76 and her heart rate decreased to 88. Evaluation: Within one hour of administration of Ketorolac, Mrs. Jamison verbalized pain reduction to her reported satisfactory level of “3,” and her blood pressure and heart rate decreased to her baseline levels. SMART outcomes were “met.” 11.7 Learning Activities Open Resources for Nursing (Open RN) Learning Activities (Answers to “Learning Activities” can be found in the “Answer Key” at the end of the book. Answers to interactive activity elements will be provided within the element as immediate feedback.) Apply the concepts you learned from this chapter to the following patient scenario“Male_older_adult.jpg” by Shane VanderBent, Chippewa Valley Technical College is licensed under CC BY 4.0. Joe is a 68-year-old male who was recently diagnosed for colon cancer last week and underwent a colon resection three days ago. See Figure 11.15 for an image of Joe.“Male_older_adult.jpg” by Shane VanderBent, Chippewa Valley Technical College is licensed under CC BY 4.0 In the change of shift report, you hear that he is receiving morphine by PCA pump for pain, but he is not using it very often. Staff reports he “needs much encouragement” to get out of bed and participate in self-cares. He has crackles in his lung bases and his oxygen saturation is 88% on room air. - What additional assessments (subjective and objective) will you perform on Joe? - List the top three priority nursing diagnoses for Joe. - Joe states, “I don’t want to use morphine. I am afraid I will become addicted to it like my friend did after he came home from the war.” How will you respond to therapeutically address his concerns, yet also teach Joe about good pain management? - What are common side effects of opioids and how will you plan to manage these side effects for Joe? - Emotional issues could also be affecting Joe’s perception of pain. What will you further physically assess and therapeutically address? - After providing patient education about morphine and the PCA pump, you check on Joe later in the day and notice he has had five self-doses every hour with 15 attempts in the past hour. The pump is set for a maximum of 6 doses per hour. What further assessments will you perform? An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=1644#h5p-59 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=1644#h5p-29 XI Glossary Open Resources for Nursing (Open RN) Acute pain: Pain that is limited in duration and is associated with a specific cause. Addiction: A chronic disease of the brain’s reward, motivation, memory, and related circuitry reflected in an individual pathologically pursuing reward and/or relief by substance use and other behaviors. Addiction is characterized by several symptoms, such as the inability to consistently abstain from a substance, impaired behavioral control, cravings, diminished recognition of significant problems with one’s behaviors and interpersonal relationships, and a dysfunctional emotional response. Adjuvant: Medication that is not classified as an analgesic but has been found in clinical practice to have either an independent analgesic effect or additive analgesic properties when administered with opioids. Analgesics: Medications used to relieve pain. Chronic pain: Pain that is ongoing and persistent for longer than six months. Misuse: Taking prescription pain medications in a manner or dose other than prescribed; taking someone else’s prescription, even if for a medical complaint such as pain; or taking a medication to feel euphoria (i.e., to get high). Neuropathic pain: Pain caused by a lesion or disease of the somatosensory nervous system that is typically described by patients as “burning” or “like pins and needles.” Nociceptor: A sensory receptor for painful stimuli. Pain: An unpleasant sensory and emotional experience associated with, or resembling that associated with, actual or potential tissue damage. Patient-Controlled Analgesia (PCA): A method of pain management that allows hospitalized patients with severe pain to safely self-administer opioid medications using a programmed pump according to their level of discomfort. Physical dependence: Withdrawal symptoms that occur when chronic pain medication is suddenly reduced or stopped because of physiological adaptations that occur from chronic exposure to the medication. Referred pain: Pain perceived at a location other than the site of the painful stimulus. For example, pain from retained gas in the colon can cause pain to be perceived in the shoulder. Substance abuse disorder: Significant impairment or distress from a pattern of substance use (i.e., alcohol, drugs or misuse of prescription medications). Tolerance: A reduced response to pain medication when the same dose of a drug has been given repeatedly, requiring a higher dose of the drug to achieve the same level of response. Sleep and Rest XII 12.1 Sleep & Rest Introduction Open Resources for Nursing (Open RN) Learning Objectives - Assess factors that put patients at risk for problems with sleep - Identify factors related to sleep/rest across the life span - Recognize characteristics of sleep deprivation - Consider the use of nonpharmacological measures to promote sleep and rest - Identify evidence-based practices Maslow’s hierarchy of needs indicates sleep as one of our physiological requirements. Getting enough quality sleep at the right times according to our circadian rhythms can protect mental and physical health, safety, and quality of life. Conversely, chronic sleep deficiency increases the risk of heart disease, kidney disease, high blood pressure, diabetes, and stroke, as well as weakening the immune system.Trossman, S. (2018, November 7). Nurses offer strategies to promote patients’ rest and sleep. American Nurse. https://www.myamericannurse.com/strategies-promote-patients-rest-sleep/ This chapter will review the physiology of sleep and common sleep disorders, as well as interventions to promote good sleep. 12.2 Basic Concepts Open Resources for Nursing (Open RN) What Causes Sleep? There are two internal biological mechanisms that work together to regulate wakefulness and sleep referred to as circadian rhythms and sleep-wake homeostasis. Circadian rhythms direct a wide variety of body functions including wakefulness, core temperature, metabolism, and the release of hormones. They control the timing of sleep, causing a person to feel sleepy at night and creating a tendency to wake in the morning without an alarm. See Figure 12.1“The_master_circadian_clock_in_the_human_brain.jpg” by Ian B. Hickie, Sharon L. Naismith, Rébecca Robillard, Elizabeth M. Scott, and Daniel F. Hermens is licensed under CC BY 3.0 for an illustration of circadian rhythms. Circadian rhythms are based roughly on a 24-hour clock and use environmental cues, such as light and temperature to determine the time of day.National Institute of Neurological Disorders and Stroke. (2019, August 13). Understanding sleep. U.S. Department of Health & Human Services. https://www.ninds.nih.gov/Disorders/Patient-Caregiver-Education/Understanding-Sleep Sleep-wake homeostasis keeps track of a person’s need for sleep. A pressure to sleep builds with every hour that a person is awake, reaching a peak in the evening when most people fall asleep. The homeostatic sleep drive also regulates sleep intensity, causing a person to sleep longer and more deeply after a period of sleep deprivation.National Institute of Neurological Disorders and Stroke. (2019, August 13). Understanding sleep. U.S. Department of Health & Human Services. https://www.ninds.nih.gov/Disorders/Patient-Caregiver-Education/Understanding-Sleep Adenosine is linked to this drive for sleep. While awake, the level of adenosine in the brain continues to rise, with increased levels signaling a shift toward sleep. While sleeping, the body breaks down adenosine. When it gets dark, the body also releases a hormone called melatonin. Melatonin signals the body that it’s time to prepare for sleep and creates a feeling of drowsiness. The amount of melatonin in the bloodstream peaks as the evening wears on. A third hormone, cortisol, is released in the early morning hours and naturally prepares the body to wake up.National Heart, Lung, and Blood Institute. (n.d). Sleep deprivation and deficiency. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/sleep-deprivation-and-deficiency Factors that influence a person’s sleep and wakefulness include medical conditions, medications, stress, sleep environment, and foods and fluids consumed, but the greatest influence is exposure to light. Specialized cells in the retina process light and provide messages to the brain to align the body clock with periods of day or night. Exposure to bright artificial light in the late evening can disrupt this process, making it hard to fall asleep. Examples of bright artificial light include the light from a TV screen, computer, or smartphone. Exposure to light can also make it difficult to return to sleep after being awakened.National Heart, Lung, and Blood Institute. (n.d). Sleep deprivation and deficiency. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/sleep-deprivation-and-deficiency Night shift workers often have trouble falling asleep when they go to bed and may have trouble staying awake at work because their natural circadian rhythm and sleep-wake cycle are disrupted. Jet lag also disrupts circadian rhythms. When flying to a different time zone, a mismatch is created between a person’s internal clock and the actual time of day.National Institute of Neurological Disorders and Stroke. (2019, August 13). Understanding sleep. U.S. Department of Health & Human Services. https://www.ninds.nih.gov/Disorders/Patient-Caregiver-Education/Understanding-Sleep The rhythm and timing of the body clock change with age. For example, teenagers fall asleep later at night than younger children and adults because melatonin is released and peaks later in the 24-hour cycle for teens. As a result, it’s natural for many teens to prefer later bedtimes at night and sleep later in the morning than adults.National Heart, Lung, and Blood Institute. (n.d). Sleep deprivation and deficiency. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/sleep-deprivation-and-deficiency Individuals also need more sleep early in life, when they’re growing and developing. For example, newborns may sleep more than 16 hours a day, and preschool-aged children need to take naps. Young children tend to sleep more in the early evening whereas older adults tend to go to bed earlier and wake up earlier.National Heart, Lung, and Blood Institute. (n.d). Sleep deprivation and deficiency. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/sleep-deprivation-and-deficiency Sleep Phases and Stages When sleeping, individuals cycle through two phases of sleep: rapid eye movement (REM) and non-REM sleep. A full sleep cycle takes 80 to 100 minutes to complete, and most people typically cycle through four to six cycles per night. It is common to wake up briefly between cycles.National Heart, Lung, and Blood Institute. (n.d). How sleep works. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/how-sleep-works Restoration takes place mostly during slow-wave non-REM sleep, during which the body’s temperature, heart rate, and brain oxygen consumption decrease. Brain activity decreases, so this stage is also referred to as slow-wave sleep and is observed during sleep studies. Non-REM sleep has these three stages: - Stage 1: The transition between wakefulness and sleep. - Stage 2: The initiation of the sleep phase. - Stage 3: The deep sleep or slow-wave sleep stage based on a pattern that appears during measurements of brain activity. Individuals spend the most amount of sleep time in this stage during the early part of the night. (Note that the previously considered 4th stage of non-REM sleep is now included within Stage 3).National Heart, Lung, and Blood Institute. (n.d). How sleep works. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/how-sleep-works During REM sleep, a person’s heart rate and respiratory rate increase. Eyes twitch as they rapidly move back and forth and the brain is active. Brain activity measured during REM sleep is similar to activity during waking hours. Dreaming occurs during REM sleep, and muscles normally become limp to prevent acting out one’s dreams. People typically experience more REM sleep as the night progresses. However, hot and cold environments can affect a person’s REM sleep because the body does not regulate temperature well during REM sleep.National Heart, Lung, and Blood Institute. (n.d). How sleep works. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/how-sleep-works See Figure 12.2“The_master_circadian_clock_in_the_human_brain.jpg” by Ian B. Hickie, Sharon L. Naismith, Rébecca Robillard, Elizabeth M. Scott, and Daniel F. Hermens is licensed under CC BY 3.0 for an image illustrating stages of sleep with increased REM sleep through the night indicated in solid red lines. The patterns and types of sleep change as people mature. For example, newborns spend more time in REM sleep. The amount of slow-wave sleep peaks in early childhood and then drops sharply in the teenage years. Slow-wave sleep continues to decrease through adulthood, and older people may not have any slow-wave sleep at all.National Heart, Lung, and Blood Institute. (n.d). How sleep works. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/how-sleep-works Why Is Sleep Important? Sleep plays a vital role in good health and well-being. Getting enough quality sleep at the right times protects mental health and physical health. Lack of sleep affects daytime performance, quality of life, and safety. The way a person feels while awake depends on what happens while they are sleeping. During sleep, the body is working to support healthy brain function and maintain physical health. In children and teens, sleep also helps support growth and development.National Heart, Lung, and Blood Institute. (n.d). Sleep deprivation and deficiency. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/sleep-deprivation-and-deficiency Healthy Brain Function and Emotional Well-Being Sleep helps the brain work properly. While sleeping, the brain is forming new pathways to help a person learn and remember information. Studies show that a good night’s sleep improves learning and problem-solving skills. Sleep also helps a person pay attention, make decisions, and be creative. Conversely, sleep deficiency alters activity in some parts of the brain, causing difficulty in making decisions, solving problems, controlling emotions and behavior, and coping with change. Sleep deficiency has also been linked to depression, suicide, and risk-taking behavior.National Heart, Lung, and Blood Institute. (n.d). Sleep deprivation and deficiency. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/sleep-deprivation-and-deficiency Physical Health Sleep also plays an important role in physical health. For example, sleep is involved in healing and repairing the heart and blood vessels. Ongoing sleep deficiency is linked to an increased risk of heart disease, kidney disease, high blood pressure, diabetes, and stroke. Sleep helps maintain a healthy balance of the hormones that cause hunger (ghrelin) or a feeling of fullness (leptin). When a person doesn’t get enough sleep, the level of ghrelin increases and the level of leptin decreases, causing a person to feel hungry when sleep deprived. The way the body responds to insulin is also affected, causing increased blood sugar.National Heart, Lung, and Blood Institute. (n.d). Sleep deprivation and deficiency. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/sleep-deprivation-and-deficiency Sleep supports healthy growth and development. Deep sleep triggers the body to release hormones that promote normal growth in children and teens. See Figure 12.3.“6041578611_f2c9e4d164_k.jpg” by rachel CALAMUSA is licensed under CC BY-SA 2.0 of a sleeping child. These hormones also boost muscle mass and help repair cells and tissues.National Heart, Lung, and Blood Institute. (n.d). Sleep deprivation and deficiency. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/sleep-deprivation-and-deficiency Daytime Performance Getting enough quality sleep at the right times also enhances functioning throughout the day. People who are sleep deficient are less productive at work and school. They take longer to finish tasks, have a slower reaction time, and make more mistakes. After several nights of losing sleep, even a loss of just 1 or 2 hours per night, the ability to function declines.National Heart, Lung, and Blood Institute. (n.d). Sleep deprivation and deficiency. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/sleep-deprivation-and-deficiency See Figure 12.4“Study_sleep.jpg” by Nic Ashman, Chippewa Valley Technical College is licensed under CC BY 4.0 for an image of a student demonstrating sleep deficiency while studying. Lack of sleep can lead to microsleep. Microsleep refers to brief moments of sleep that occur when one is normally awake. You can’t control microsleep, and you might not be aware of it. For example, have you ever driven somewhere and then not remembered part of the trip? If so, you may have experienced microsleep. Even if you’re not driving, microsleep can affect how you function. If you’re listening to a lecture, for example, you might miss some of the information or feel as if you don’t understand the point. In reality, you may have slept through part of the lecture and not been aware of experiencing microsleep.National Heart, Lung, and Blood Institute. (n.d). Sleep deprivation and deficiency. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/sleep-deprivation-and-deficiency Effects of Sleep Deficiency The damage from sleep deficiency can occur in an instant. For example, drowsy drivers may feel capable of driving. Yet, studies show that sleep deficiency harms one’s driving ability as much as, or more than, being drunk. It is estimated that driver sleepiness is a factor in about 100,000 car accidents each year, resulting in about 1,500 deaths.National Heart, Lung, and Blood Institute. (n.d). Sleep deprivation and deficiency. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/sleep-deprivation-and-deficiency Drivers aren’t the only ones affected by sleep deficiency. It can affect people in all lines of work, including health care workers, pilots, students, mechanics, and assembly line workers. As a result, sleep deficiency is harmful not only on a personal level, but also can cause large-scale damage. For example, sleep deficiency has played a role in human errors linked to tragic accidents, such as nuclear reactor meltdowns, grounding of large ships, and aviation accidents.National Heart, Lung, and Blood Institute. (n.d). Sleep deprivation and deficiency. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/sleep-deprivation-and-deficiency Sleep deficiency can also cause long-term harm. It increases the risk of obesity. For example, one study of teenagers showed that with each hour of sleep lost, the odds of becoming obese went up. Sleep deficiency increases the risk of obesity in other age groups as well. Sleep also affects how your body reacts to insulin, the hormone that controls your blood glucose (sugar) level. Sleep deficiency results in a higher than normal blood sugar level, which may increase your risk for diabetes.National Heart, Lung, and Blood Institute. (n.d). Sleep deprivation and deficiency. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/sleep-deprivation-and-deficiency Ongoing sleep deficiency can also change the way in which your immune system responds. For example, if you’re sleep deficient, you may have trouble fighting common infections.National Heart, Lung, and Blood Institute. (n.d). Sleep deprivation and deficiency. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/sleep-deprivation-and-deficiency In addition, children and teens who are sleep deficient may have problems getting along with others. They may feel angry and impulsive, have mood swings, feel sad or depressed, or lack motivation. They also may have problems paying attention, and they may get lower grades and feel stressed.National Heart, Lung, and Blood Institute. (n.d). Sleep deprivation and deficiency. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/sleep-deprivation-and-deficiency If a person routinely loses sleep or chooses to sleep less than needed, the sleep loss adds up. The total sleep lost is called sleep debt. For example, if you lose 2 hours of sleep each night, you’ll have a sleep debt of 14 hours after a week.National Heart, Lung, and Blood Institute. (n.d). Sleep deprivation and deficiency. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/sleep-deprivation-and-deficiency See Figure 12.5“8609141689_ff923d2934_k.jpg” by Navy_NADAP is licensed under CC BY-NC-ND 2.0 of an individual feeling the effects of sleep debt on awakening. Some people nap as a way to deal with sleepiness. Naps can provide a short-term boost in alertness and performance. However, napping doesn’t provide restorative sleep. Some people sleep more on their days off than on work days. They also may go to bed later and get up later on days off. Although extra sleep on days off might help a person feel better, it can upset the body’s sleep–wake rhythm.National Heart, Lung, and Blood Institute. (n.d). Sleep deprivation and deficiency. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/sleep-deprivation-and-deficiency See Figure 12.6“Sleeping_man_J2.jpg” by Jamain is licensed under CC BY-SA 3.0 of an adult napping during the day. Sleep deficiency can affect people even when they sleep the total number of hours recommended for their age group. For example, people whose sleep is out of sync with their body clocks (such as shift workers) or whose sleep is routinely interrupted (such as caregivers or emergency responders) often need to pay special attention to their sleep needs.National Heart, Lung, and Blood Institute. (n.d). Sleep deprivation and deficiency. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/sleep-deprivation-and-deficiency Individuals should also talk to a health care provider if they sleep more than eight hours a night, but don’t feel well-rested. This can indicate a sleep disorder or other health problem.National Heart, Lung, and Blood Institute. (n.d). Sleep deprivation and deficiency. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/sleep-deprivation-and-deficiency Sleep Disorders There are several sleep disorders that can cause sleep deficiency, such as insomnia, sleep apnea, and narcolepsy. Insomnia Insomnia is a common sleep disorder that causes trouble falling asleep, staying asleep, or getting good quality sleep. Insomnia interferes with daily activities and causes the person to feel unrested or sleepy during the day.National Heart, Lung, and Blood Institute. (n.d). Insomnia. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/insomnia Short-term insomnia may be caused by stress or changes in one’s schedule or environment. It can last for a few days or weeks. Chronic insomnia occurs three or more nights a week, lasts more than three months, and cannot be fully explained by another health problem or a medication. Chronic insomnia raises the risk of high blood pressure, coronary heart disease, diabetes, and cancer.National Heart, Lung, and Blood Institute. (n.d). Insomnia. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/insomnia Symptoms of insomnia include the following: - Lying awake for a long time before falling asleep. This is more common in younger adults. - Sleeping for only short periods due to waking up often during the night or being awake for most of the night. This is the most common symptom and typically affects older adults. - Waking up too early in the morning and not being able to get back to sleep. - Having poor-quality of sleep that causes one to wake up feeling unrested. The person often feels sleepy during the day and has difficulty focusing on tasks. Insomnia can also cause irritability, anxiousness, and depression.National Heart, Lung, and Blood Institute. (n.d). Insomnia. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/insomnia See Figure 12.7“Depiction_of_a_person_suffering_from_Insomnia_(sleeplessness).png” by https://www.myupchar.com/en is licensed under CC BY-SA 4.0 for an illustration of insomnia. To diagnose insomnia, the health care provider asks about a person’s sleep habits and may request the person to keep a sleep diary for 1-2 weeks. A sleep diary records the time a person goes to sleep, wakes up, and takes naps each day. Timing of activities such as exercising and drinking caffeine or alcohol are also recorded, as well as feelings of sleepiness throughout the day.National Heart, Lung, and Blood Institute. (n.d). Insomnia. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/insomnia A sleep study may be ordered to look for other sleep problems, such as circadian rhythm disorders, sleep apnea, and narcolepsy. Treatment Lifestyle changes often help improve short-term insomnia. The patient should be educated about healthy sleep habits, such as the following: - Make your bedroom sleep-friendly. Sleep in a cool, quiet place. Avoid artificial light from the TV or electronic devices, as this can disrupt your sleep-wake cycle. - Go to sleep and wake up around the same times each day, even on the weekends. If you can, avoid night shifts, irregular schedules, or other things that may disrupt your sleep schedule. - Avoid caffeine, nicotine, and alcohol before bedtime. Although alcohol can make it easier to fall asleep, it triggers sleep that tends to be lighter than normal. This makes it more likely that you will wake up during the night. The effect of caffeine can last as long as eight hours. - Get regular physical activity during the daytime (at least 5 to 6 hours before going to bed). Exercising close to bedtime can make it harder to fall asleep. - Avoid daytime naps, especially in the afternoon. This may help you sleep longer at night. - Eat meals on a regular schedule and avoid late-night dinners to maintain a regular sleep-wake cycle. - Limit how much fluid you drink close to bedtime. This may help you sleep longer without having to use the bathroom. - Learn new ways to manage stress. Follow a routine that helps you wind down and relax before bed. For example, read a book, listen to soothing music, or take a hot bath. Your doctor may also recommend massage therapy, meditation, or yoga to help you relax. Acupuncture may also help improve insomnia, especially in older adults. - Avoid certain over-the-counter and prescription medicines that can disrupt sleep (for example, some cold and allergy medicines).National Heart, Lung, and Blood Institute. (n.d). Insomnia. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/insomnia A type of counseling called cognitive behavioral therapy for insomnia is usually the first treatment recommended for chronic insomnia. Several prescription medications may also be prescribed to treat insomnia. Some are meant for short-term use while others are meant for long-term use. Some insomnia medications can be habit-forming, and they all can cause dizziness, drowsiness, or worsening of depression or suicidal thoughts.National Heart, Lung, and Blood Institute. (n.d). Insomnia. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/insomnia Common medications prescribed to treat insomnia are as follows: - Benzodiazepines, such as lorazepam (Ativan). Benzodiazepines can be habit-forming and should be taken for only a few weeks. They can interfere with REM sleep. - Benzodiazepine-receptor agonists, such as zolpidem (Ambien). Side effects may include anxiety. Rare side effects may include a severe allergic reaction or unintentionally doing activities while asleep such as walking, eating, or driving. - Melatonin-receptor agonists, such as ramelteon (Rozerem). Rare side effects may include doing activities while asleep, such as walking, eating, or driving, or a severe allergic reaction. - Orexin-receptor antagonists, such as suvorexant (Belsomra). This medicine is not recommended for people who have narcolepsy. Rare side effects may include doing activities while asleep, such as walking, eating, or driving, or not being able to move or speak for several minutes while going to sleep or waking up.National Heart, Lung, and Blood Institute. (n.d). Insomnia. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/insomnia Some patients use over-the-counter (OTC) products as sleep aids. Many contain antihistamines that cause sleepiness. However, they can be unsafe for some people and may not be the best treatment for insomnia. Melatonin supplements are lab-made versions of the sleep hormone melatonin. Many people take melatonin supplements to improve their sleep. However, research has not proven that melatonin is an effective treatment for insomnia. Side effects of melatonin may include daytime sleepiness, headaches, upset stomach, and worsening depression. It can also affect the body’s control of blood pressure, causing high or low blood pressure.National Heart, Lung, and Blood Institute. (n.d). Insomnia. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/insomnia Sleep Apnea Sleep apnea is a common sleep condition that occurs when the upper airway becomes repeatedly blocked during sleep, reducing or completely stopping airflow. If the brain does not send the signals needed to breathe, the condition may be called central sleep apnea.National Heart, Lung, and Blood Institute. (n.d). Sleep apnea. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/sleep-apnea Sleep apnea can be caused by a person’s physical structure or other medical conditions. Risk factors include obesity (causing fat deposits in the neck), large tonsils (that narrow the airway), thyroid disorders, neuromuscular disorders, heart or kidney failure (causing fluid buildup in the neck that narrows the airway), genetic syndromes (such as cleft lip or Down’s syndrome), and premature birth (before 37 weeks gestation).National Heart, Lung, and Blood Institute. (n.d). Sleep apnea. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/sleep-apnea Common signs and symptoms of sleep apnea include the following: - Reduced or absent breathing, known as apnea events - Frequent loud snoring - Gasping for air during sleep - Excessive daytime sleepiness and fatigue - Decreases in attention, vigilance, concentration, motor skills, and verbal and visuospatial memory - Dry mouth or headaches when waking - Sexual dysfunction or decreased libido - Waking up often during the night to urinateNational Heart, Lung, and Blood Institute. (n.d). Sleep apnea. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/sleep-apnea Sleep apnea is diagnosed by a health care provider based on the person’s medical history, a physical exam, and results from a sleep study. During sleep studies, the number of episodes of slowed or stopped breathing events are recorded, along with documentation of oxygen levels in the blood during these events.National Heart, Lung, and Blood Institute. (n.d). Sleep apnea. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/sleep-apnea Treatment A breathing device, such as a CPAP machine, is the most commonly recommended treatment for patients with sleep apnea. CPAP stands for continuous positive airway pressure therapy. It uses mild air pressure to keep the airways open. See Figure 12.8“Depiction_of_a_Sleep_Apnea_patient_using_a_CPAP_machine.png” by https://www.myupchar.com/en is licensed under CC BY-SA 4.0 for an illustration of a CPAP. A mouthpiece may be prescribed for patients with mild sleep apnea or if the apnea occurs only when lying on their back. Mouthpieces, or oral appliances, are custom-fit devices that are worn while sleeping. See Figure 12.9“Orthoapnea_,_oral_appliance.jpg” by Orthoapnea is licensed under CC BY-SA 3.0 and “3D_printed_mouthpeace.jpg” by unknown author is licensed under CC BY 3.0 for examples of mouthpieces used to treat sleep apnea. Mouthpieces are custom-fit by a dentist or an orthodontist to the patient’s mouth and jaw. There are two types of mouthpieces that work differently to open the upper airway. Mandibular repositioning mouthpieces are devices that cover the upper and lower teeth and hold the jaw in a position that prevents it from blocking the upper airway. Tongue-retaining devices are mouthpieces that hold the tongue in a forward position to prevent it from blocking the upper airway.National Heart, Lung, and Blood Institute. (n.d). Sleep apnea. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/sleep-apnea Narcolepsy Narcolepsy is an uncommon sleep disorder that causes periods of extreme daytime sleepiness and sudden, brief episodes of deep sleep during the day. Signs and symptoms of narcolepsy include extreme daytime sleepiness; falling asleep without warning, called sleep attacks; difficulty focusing or staying awake; and waking frequently at night. Individuals may experience hallucinations while falling asleep or waking up or sleep paralysis, a feeling of being awake but being unable to move for several minutes. Narcolepsy is diagnosed based on medical history, family history, a physical exam, and a sleep study. The sleep study looks at daytime naps to identify disturbed sleep or a quick onset of rapid eye movement (REM) sleep. Treatment for narcolepsy combines medications and behavior changes. Medications used to treat narcolepsy include stimulants, modafinil, and sodium oxybate to treat daytime sleepiness, and sedatives to improve nighttime sleep. Daytime sleepiness is often improved by promoting good quality sleep at night with scheduled naps during the day.National Heart, Lung, and Blood Institute. (n.d). Narcolepsy. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/narcolepsy 12.3 Applying the Nursing Process Open Resources for Nursing (Open RN) Assessment Begin a focused assessment on a patient’s sleep patterns by asking an open-ended question such as, “Do you feel rested upon awakening?” From there, five key sleep characteristics should be assessed: sleep duration, sleep quality, sleep timing, daytime alertness, and the presence of a sleep disorder. Examples of focused interview questions are included in Table 12.3a. These questions have been selected from sleep health questionnaires from the National Sleep Foundation’s Sleep Health Index and the National Healthy Sleep Awareness Project.Chaput, J., & Shiau, J. (2019). Routinely assessing patients’ sleep health is time well spent. Preventive Medicine Reports, 14. https://doi.org/10.1016/j.pmedr.2019.100851 Table 12.3a Focused Interview Questions Regarding SleepChaput, J., & Shiau, J. (2019). Routinely assessing patients’ sleep health is time well spent. Preventive Medicine Reports, 14. https://doi.org/10.1016/j.pmedr.2019.100851 \| Questions \| Desired Answers \| \|---\|---\| \| How many hours do you sleep on an average night? \| 7-8 hours for adults (See Table 12.3b for recommended sleep by age range.) \| \| During the past month, how would you rate your sleep quality overall? \| Very good or fairly good \| \| Do you go to bed and wake up at the same time every day, even on weekends? \| Yes, maintain a consistent sleep schedule in general \| \| How likely is it for you to fall asleep during the daytime without intending to struggle to stay awake while you are doing things? \| Unlikely \| \| How often do you have trouble going to sleep or staying asleep? \| Never, rarely, or sometimes \| \| During the past 2 weeks, how many days did you have loud snoring? Note: It is helpful to ask the patient’s sleep partner this question. \| Never \| It is also helpful to determine the effects of caffeine intake and medications on a patient’s sleep pattern. If a patient provides information causing a concern for impaired sleep patterns or a sleep disorder, it is helpful to encourage them to create a sleep diary to share with a health care provider. Use the following hyperlink to view a sample sleep diary. Download a Sleep Diary from the National Heart, Lung, and Blood Institute. Additional subjective assessment questions can be used to gather information about a patient’s typical sleep routine so that it can be mirrored during inpatient care, when feasible. Nurses also perform objective assessments of a patient’s sleep patterns during inpatient care. The number of hours slept, wakefulness during the night, and episodes of loud snoring or apnea should be documented. Note physical (e.g., sleep apnea, pain, and urinary frequency) or psychological (e.g., fear or anxiety) circumstances that interrupt sleep, as well as sleepiness and napping during the day.Butcher, H., Bulechek, G., Dochterman, J., & Wagner, C. (2018). Nursing Interventions Classification (NIC). Elsevier, pp. 349-350.,Ackley, B., Ladwig, G., Makic, M. B., Martinez-Kratz, M., & Zanotti, M. (2020). Nursing diagnosis handbook: An evidence-based guide to planning care (12th ed.). Elsevier. pp. 843-846. Concerns about signs of sleep disorders should be communicated to the health care provider for follow-up. Life Span Considerations The amount of sleep needed changes over the course of a person’s lifetime. Although sleep needs vary from person to person, Table 12.3b shows general recommendations for different age groups based on recommendations from the American Academy of Sleep Medicine (AASM) and the American Academy of Pediatrics (AAP).National Heart, Lung, and Blood Institute. (n.d). Sleep deprivation and deficiency. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/sleep-deprivation-and-deficiency Table 12.3b Recommended Amounts of Sleep by Age GroupNational Heart, Lung, and Blood Institute. (n.d). Sleep deprivation and deficiency. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/sleep-deprivation-and-deficiency \| Age \| Recommended Amount of Sleep \| \|---\|---\| \| Infants aged 4-12 months \| 12-16 hours a day (including naps) \| \| Children aged 1-2 years \| 11-14 hours a day (including naps) \| \| Children aged 3-5 years \| 10-13 hours a day (including naps) \| \| Children aged 6-12 years \| 9-12 hours a day \| \| Teens aged 13-18 years \| 8-10 hours a day \| \| Adults aged 18 years or older \| 7–8 hours a day \| If an older adult has Alzheimer’s disease, it often changes their sleeping habits. Some people with Alzheimer’s disease sleep too much; others don’t sleep enough. Some people wake up many times during the night; others wander or yell at night. The person with Alzheimer’s disease isn’t the only one who loses sleep. Caregivers may have sleepless nights, leaving them tired for the challenges they face. Educate caregivers about these steps to promote safety for their loved one, and help them and the patient sleep better at night: - Make sure the floor is clear of objects. - Lock up any medications. - Attach grab bars in the bathroom. - Place a gate across the stairs.National Institute on Aging. (2016, May 1). A good night’s sleep. U.S. Department of Health & Human Services. https://www.nia.nih.gov/health/good-nights-sleep#safe Diagnostic Tests A sleep study may be ordered for a patient suspected of having a sleep disorder. A sleep study monitors and records data during a patient’s full night of sleep. A sleep study may be performed at a sleep center or at home with a portable diagnostic device. If done at a sleep center, the patient will sleep in a bed at the sleep center for the duration of the study. Removable sensors are placed on the person’s scalp, face, eyelids, chest, limbs, and a finger to record brain waves, heart rate, breathing effort and rate, oxygen levels, and muscle movements before, during, and after sleep. There is a small risk of irritation from the sensors, but this will resolve after they are removed.National Heart, Lung, and Blood Institute. (n.d). Insomnia. U.S. Department of Health & Human Services. https://www.nhlbi.nih.gov/health-topics/insomnia See Figure 12.10“Wired_up_for_a_sleep_study_02A.jpg” by Joe Mabel is licensed under CC BY-SA 3.0 of an image of a patient with sensors in place for a sleep study. Diagnoses NANDA-I nursing diagnoses related to sleep include Disturbed Sleep Pattern, Insomnia, Readiness for Enhanced Sleep, and Sleep Deprivation.Herdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York, pp. 214-216. When creating a nursing care plan for a patient, review a nursing care planning source for current NANDA-I approved nursing diagnoses and interventions related to sleep. See Table 12.3c for the definition and selected defining characteristics of Sleep Deprivation.Herdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York, pp. 214-216. Table 12.3c Sample NANDA-I Nursing Diagnosis Related to Sleep DeprivationHerdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York, pp. 214-216. \| NANDA-I Diagnosis \| Definition \| Selected Defining Characteristics \| \|---\|---\|---\| \| Sleep Deprivation \| Prolonged periods of time without sustained natural, periodic suspension of relative consciousness that provides rest. \| Agitation Alteration in concentration Anxiety Apathy Combativeness Decrease in functional ability Decrease in reaction time Drowsiness Fatigue Hallucinations Heightened sensitivity to pain Irritability Restlessness \| A sample PES statement is, “Sleep Deprivation related to an overstimulating environment as evidenced by irritability, difficulty concentrating, and drowsiness.” Outcome Identification An overall goal related to sleep is, “The patient will awaken refreshed once adequate time is spent sleeping.”Ackley, B., Ladwig, G., Makic, M. B., Martinez-Kratz, M., & Zanotti, M. (2020). Nursing diagnosis handbook: An evidence-based guide to planning care (12th ed.). Elsevier. pp. 843-846. A sample SMART outcome is, “The patient will identify preferred actions to ensure adequate sleep by discharge.”Ackley, B., Ladwig, G., Makic, M. B., Martinez-Kratz, M., & Zanotti, M. (2020). Nursing diagnosis handbook: An evidence-based guide to planning care (12th ed.). Elsevier. pp. 843-846. Planning Interventions Since the days of Florence Nightingale, sleep has been recognized as beneficial to health and of great importance during nursing care due to its restorative function. It is common for sleep disturbances and changes in sleep pattern to occur in connection with hospitalization, especially among surgical patients. Patients in medical and surgical units often report disrupted sleep, not feeling refreshed by sleep, wakeful periods during the night, and increased sleepiness during the day. Illness and the stress of being hospitalized are causative factors, but other reasons for insufficient sleep in hospitals may be due to an uncomfortable bed, being too warm or too cold, environmental noise such as IV pump alarms, disturbance from health care personnel and other patients, and pain. The presence of intravenous catheters, a urinary catheter, and drainage tubes can also impair sleep. Increased daytime sleepiness, a consequence of poor quality sleep at night, can cause decreased mobility and slower recovery from surgery. Research indicates that postoperative sleep disturbances can last for months. Therefore, it is important to provide effective nursing interventions to promote sleep.Hellström, A., Fagerström, C., & Willman, A. (2011). Promoting sleep by nursing interventions in health care settings: A systematic review. Worldviews on Evidence-Based Nursing, 8(3), 128–142. https://doi.org/10.1111/j.1741-6787.2010.00203.x A literature review found evidence for effective nursing interventions including massage, acupuncture, and music or natural sounds. Because massage requires trained personnel and can be somewhat time-consuming, it might only be feasible in particular environments. However, as a promoter of sleep, massage is effective in severely ill patients.Hellström, A., Fagerström, C., & Willman, A. (2011). Promoting sleep by nursing interventions in health care settings: A systematic review. Worldviews on Evidence-Based Nursing, 8(3), 128–142. https://doi.org/10.1111/j.1741-6787.2010.00203.x Nurses nationwide have been looking at innovative and common sense ways to transform hospitals into more restful environments. As reported in the American Nurse, strategies include using red lights at night, reducing environmental noise, bundling care, offering sleep aids, and providing patient education.Trossman, S. (2018, November 7). Nurses offer strategies to promote patients’ rest and sleep. American Nurse. https://www.myamericannurse.com/strategies-promote-patients-rest-sleep/ One strategy included reducing patients’ light exposure by switching to red lights during the night while using Actiwatches to measure specific light color exposure, sleep, and activity. Both adult and pediatric patients were found to sleep better with reduced white lights, and the red light met the visual needs of nurses while providing care at night.Trossman, S. (2018, November 7). Nurses offer strategies to promote patients’ rest and sleep. American Nurse. https://www.myamericannurse.com/strategies-promote-patients-rest-sleep/ In addition to reducing light, nurses also sought to reduce environmental noise. Patients were surveyed regarding factors that affected their ability to sleep, and results indicated bed noises, alarms, squeaking equipment, and sounds from other patients. The nurses’ efforts led to a number of changes, including replacing the wheels on the trash cans and squeaky wheels on chairs, repairing malfunctioning motors on beds, switching automatic paper towel machines in the hallways with manual ones, and altering the times floors were buffed. Nursing staff also developed visitor rules, such as no overnight stays in semiprivate rooms. Overnight visitors in private rooms were asked to honor the quiet environment by not using their cell phones, turning on TVs, or using bright lights at night.Trossman, S. (2018, November 7). Nurses offer strategies to promote patients’ rest and sleep. American Nurse. https://www.myamericannurse.com/strategies-promote-patients-rest-sleep/ In addition to addressing light and noise, nurses also reinforced the importance of bundling care by interdisciplinary team members to reduce sleep interruptions. One interdisciplinary effort is called “Quiet Time” that occurs from 2 p.m. to 4 p.m. and from midnight to 5 a.m. Quiet Time includes dimming lights, closing patient room doors, and talking in lower voices. To bolster this intervention, project team members used a staff intervention called “Hushpuppies.” The aim of the intervention was to build staff awareness and accountability around noise they generate during these Quiet Times, often without realizing it. At the beginning of the shift, everyone, including physicians, is given a clothespin. If someone hears one of their peers talking too loudly, for example, they take away that person’s clothespin. Whoever has the most clothespins at the end of the shift receives a gift card for coffee. The project team felt that Hushpuppies worked well because it allowed staff to address loud conversations and other noise and hold each other accountable in a nonconfrontational way.Trossman, S. (2018, November 7). Nurses offer strategies to promote patients’ rest and sleep. American Nurse. https://www.myamericannurse.com/strategies-promote-patients-rest-sleep/ Other pro-sleep strategies included asking patients about what aids they use at home to help them sleep, such as extra pillows or listening to music. On admission, patients were given small hospitality kits that included ear plugs and eye masks, along with the offer to use a white noise machine. After dinnertime, warm washcloths were offered to patients. Patients and families were also provided with printed materials on the benefits of sleep and rest, such as decreased length of stay, the prevention of delirium, and the ability of patients to participate in more educational activities and cardiac rehabilitation.Trossman, S. (2018, November 7). Nurses offer strategies to promote patients’ rest and sleep. American Nurse. https://www.myamericannurse.com/strategies-promote-patients-rest-sleep/ See a summary of other evidence-based nursing interventions used to promote sleep in the following box. Sleep Enhancement InterventionsButcher, H., Bulechek, G., Dochterman, J., & Wagner, C. (2018). Nursing Interventions Classification (NIC). Elsevier, pp. 349-350.,Ackley, B., Ladwig, G., Makic, M. B., Martinez-Kratz, M., & Zanotti, M. (2020). Nursing diagnosis handbook: An evidence-based guide to planning care (12th ed.). Elsevier. pp. 843-846. - Adjust the environment (e.g., light, noise, temperature, mattress, and bed) to promote sleep - Encourage the patient to establish a bedtime routine to facilitate wakefulness to sleep - Facilitate maintenance of the patient’s usual bedtime routines during inpatient care - Encourage elimination of stressful situations before bedtime - Instruct the patient to avoid bedtime foods and beverages that interfere with sleep - Encourage the patient to limit daytime sleep and participate in activity, as appropriate - Bundle care activities to minimize the number of awakenings by staff to allow for sleep cycles of at least 90 minutes - Consider sleep apnea as a possible cause and notify the provider for a possible referral for a sleep study when daytime drowsiness occurs despite adequate periods of undisturbed night sleep - Educate the patient regarding sleep-enhancing techniques Pharmacological Interventions See specific information about medications used to facilitate sleep in the previous “Sleep Disorders” section of this chapter. Implementing Interventions When implementing interventions to promote sleep, it is important to customize them according to the specific patient’s needs and concerns. If medications are administered to promote sleep, fall precautions should be implemented, and the nurse should monitor for potential side effects, such as dizziness, drowsiness, worsening of depression or suicidal thoughts, or unintentionally walking or eating while asleep. Evaluation When evaluating the effectiveness of interventions, start by asking the patient how rested they feel upon awakening. Determine the effectiveness of interventions based on the established SMART outcomes customized for each patient situation. 12.4 Putting It All Together Patient Scenario Mrs. Salvo is a 65-year-old woman admitted to the hospital for a gastrointestinal (GI) bleed. She has been hospitalized for three days on the medical surgical floor. During this time, she has received four units of PRBCs, has undergone a colonoscopy, upper GI series, and had hemoglobin levels drawn every four hours. The nurse reports to the patient’s room to conduct an assessment prior to beginning the 11 p.m.-7 a.m. shift. Although Mrs. Salvo’s hemoglobin has stabilized for the last 24 hours, Mrs. Salvo appears fatigued with bags under her eyes. In conversation with her, she yawns frequently and wanders off in her train of thought. She reports, “You can’t get any rest in here. I am poked and prodded at least once an hour.” Applying the Nursing Process Assessment: The nurse notes that Mrs. Salvo has bags under her eyes, is yawning frequently, reports difficulty achieving rest, and seems to have difficulty following the conversation. Based on the assessment information that has been gathered, the following nursing care plan is created for Mrs. Salvo: Nursing Diagnosis: Disturbed Sleep Pattern related to interruptions for therapeutic monitoring. Overall Goal: The patient will demonstrate improvement in sleeping pattern. SMART Expected Outcome: Mrs. Salvo will report feeling more rested on awakening within 24 hours. Planning and Implementing Nursing Interventions: The nurse will assess the patient’s sleep pattern and therapeutic monitoring disturbances. The nurse will group lab draws, vital signs, assessments, and other care tasks to decrease sleep disruption. The nurse will ensure the patient’s door is closed and lighting is turned down to create a restful environment. The nurse will complete as many tasks as possible when Mrs. Salvo is awake and advocate with the interprofessional team for uninterrupted periods of rest during the night. Sample Documentation: Mrs. Salvo has a disturbed sleep pattern due to frequent therapeutic monitoring. Mrs. Salvo reports difficulty achieving rest, and despite stabilization in hemoglobin level, continues to demonstrate signs of fatigue. Interventions have been implemented to group therapeutic care to minimize disruption to the patient’s sleep. Evaluation: The following morning, Mrs. Salvo reports improved feeling more rested with fewer awakenings throughout the night. SMART outcome “met.” 12.5 Learning Activities Open Resources for Nursing (Open RN) Learning Activities (Answers to “Learning Activities” can be found in the “Answer Key” at the end of the book. Answers to interactive activity elements will be provided within the element as immediate feedback.) Scenario A A nurse is caring for a patient who has been hospitalized after undergoing hip-replacement surgery. The patient complains of not sleeping well and feels very drowsy during the day. - What factors are affecting the patient’s sleep pattern? - What assessments should the nurse perform? - What SMART outcome can be established for this patient? - Outline interventions the nurse can implement to enhance sleep for this patient. - How will the nurse evaluate if the interventions are effective? Scenario B A nurse is assigned to work rotating shifts and develops difficulty sleeping. - Why do rotating shifts affect a person’s sleep pattern? - What are the symptoms of insomnia? - Describe healthy sleep habits the nurse can adopt for more restful sleep. An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=1895#h5p-68 XII Glossary Open Resources for Nursing (Open RN) Circadian rhythms: Body rhythms that direct a wide variety of functions, including wakefulness, body temperature, metabolism, and the release of hormones. They control the timing of sleep, causing individuals to feel sleepy at night and creating a tendency to wake in the morning without an alarm. Insomnia: A common sleep disorder that causes trouble falling asleep, staying asleep, or getting good quality sleep. Insomnia interferes with daily activities and causes the person to feel unrested or sleepy during the day. Short-term insomnia may be caused by stress or changes in one’s schedule or environment, lasting a few days or weeks. Chronic insomnia occurs three or more nights a week, lasts more than three months, and cannot be fully explained by another health problem or a medicine. Chronic insomnia raises the risk of high blood pressure, coronary heart disease, diabetes, and cancer. Microsleep: Brief moments of sleep that occur when a person is awake. A person can’t control microsleep and might not be aware of it. Narcolepsy: An uncommon sleep disorder that causes periods of extreme daytime sleepiness and sudden, brief episodes of deep sleep during the day. Non-REM sleep: Slow-wave sleep when restoration takes place and the body’s temperature, heart rate, and oxygen consumption decrease. REM sleep: Rapid eye movement (REM) sleep when heart rate and respiratory rate increase, eyes twitch, and brain activity increases. Dreaming occurs during REM sleep, and muscles become limp to prevent acting out one’s dreams. Sleep apnea: A common sleep condition that occurs when the upper airway becomes repeatedly blocked during sleep, reducing or completely stopping airflow. If the brain does not send the signals needed to breathe, the condition may be called central sleep apnea. Sleep diary: A record of the time a person goes to sleep, wakes up, and takes naps each day for 1-2 weeks. Timing of activities such as exercising and drinking caffeine or alcohol are also recorded, as well as feelings of sleepiness throughout the day. Sleep study: A diagnostic test that monitors and records data during a patient’s full night of sleep. A sleep study may be performed at a sleep center or at home with a portable diagnostic device. Sleep-wake homeostasis: The homeostatic sleep drive keeps track of the need for sleep, reminds the body to sleep after a certain time, and regulates sleep intensity. This sleep drive gets stronger every hour a person is awake and causes individuals to sleep longer and more deeply after a period of sleep deprivation. Mobility XIII 13.1 Mobility Introduction Open Resources for Nursing (Open RN) Learning Objectives - Assess factors that put patients at risk for problems with mobility - Identify factors related to mobility across the life span - Assess the effects of immobility on body systems - Detail the nursing measures to prevent complications of immobility - Promote the use of effective techniques of body mechanics among caregivers, patients, and significant others - Identify evidence-based practices Sit on a sturdy chair with your legs and arms stretched out in front of you, and then try to stand. This basic mobility task can be impaired during recovery from major surgery or for patients with chronic musculoskeletal conditions. Mobility, which includes moving one’s extremities, changing positions, sitting, standing, and walking, helps avoid degradation of many body systems and prevents complications associated with immobility. Nurses assist patients to be as mobile as possible, based on their individual circumstances, to achieve their highest level of independence, prevent complications, and promote a feeling of well-being. This chapter will discuss nursing assessments and interventions related to promoting mobility. 13.2 Basic Concepts Open Resources for Nursing (Open RN) Musculoskeletal Anatomy, Physiology, and Assessment Before discussing the concept of mobility, it is important to understand the anatomy of the musculoskeletal system, common musculoskeletal conditions, and the components of a musculoskeletal system assessment. Read more about these topics in the “Musculoskeletal Assessment” chapter in Open RN Nursing Skills. Mobility and Immobility Mobility is the ability of a patient to change and control their body position. Physical mobility requires sufficient muscle strength and energy, along with adequate skeletal stability, joint function, and neuromuscular synchronization. Anything that disrupts this integrated process can lead to impaired mobility or immobility.Skalsky, A. J., & McDonald, C. M. (2012). Prevention and management of limb contractures in neuromuscular diseases. Physical Medicine and Rehabilitation Clinics of North America, 23(3), 675–687. https://doi.org/10.1016/j.pmr.2012.06.009 Mobility exists on a continuum ranging from no impairment (i.e., the patient can make major and frequent changes in position without assistance) to being completely immobile (i.e., the patient is unable to make even slight changes in body or extremity position without assistance). See Figure 13.1“hospice-1821429_960_720.jpg” by truthseeker08 is licensed under CC0 for an image of a patient with impaired physical mobility requiring assistance with a wheelchair. Functional mobility is the ability of a person to move around in their environment, including walking, standing up from a chair, sitting down from standing, and moving around in bed. The three main areas of functional mobility are the following: - Bed Mobility: The ability of a patient to move around in bed, including moving from lying to sitting and sitting to lying. - Transferring: The action of a patient moving from one surface to another. This includes moving from a bed into a chair or moving from one chair to another. - Ambulation: The ability to walk. This includes assistance from another person or an assistive device, such as a cane, walker, or crutches. Immobility can be caused by several physical and psychological factors, including acute and chronic diseases, traumatic injuries, and chronic pain. Several neurological and musculoskeletal disorders can adversely affect mobility, including osteoarthritis, rheumatoid arthritis, muscular dystrophy, cerebral palsy, multiple sclerosis, and Parkinson’s disease. Traumatic injuries, such as skeletal fractures, head injuries, or spinal injuries, also impair mobility. Diseases that cause fatigue, such as heart failure, chronic obstructive pulmonary disease, and depression, or conditions that cause pain also affect the patient’s desire to move. Effects of Immobility Patients who spend an extended period of time in bed as they recover from surgery, injury, or illness can develop a variety of complications due to loss of muscle strength (estimated at a rate of 20% per week of immobility). Regardless of the cause, immobility can cause degradation of cardiovascular, respiratory, gastrointestinal, and musculoskeletal functioning. Promoting mobility can prevent these complications from occurring. Findings from a literature review demonstrated several benefits of mobilization, including less delirium, pain, urinary discomfort, urinary tract infection, fatigue, deep vein thrombosis (DVT), and pneumonia, as well as an improved ability to void. Mobilization also decreased depression, anxiety, and symptom distress, while enhancing comfort, satisfaction, quality of life, and independence.Kalisch, B., Lee, S., & Dabney, B. (2013). Outcomes of inpatient mobilisation: A literature review. Journal of Clinical Nursing, 23(11-12), 1486-1501. https://doi.org/10.1111/jocn.12315 See Table 13.2a for a summary of the effects of immobility on these body systems.This work is a derivative of StatPearls by Javed & Davis and is licensed under CC BY 4.0,American Nurses Association. (2014). Current topics in safe patient handling and mobility. American Nurse Today (supplement). https://www.myamericannurse.com/wp-content/uploads/2014/07/ant9-Patient-Handling-Supplement-821a_LOW.pdf,Skalsky, A. J., & McDonald, C. M. (2012). Prevention and management of limb contractures in neuromuscular diseases. Physical Medicine and Rehabilitation Clinics of North America, 23(3), 675–687. https://doi.org/10.1016/j.pmr.2012.06.009 Decreased mobility is also a major risk factor for skin breakdown, as indicated on the Braden Scale. See Figure 13.2“Deep_vein_thrombosis_of_the_right_leg.jpg” by James Heilman, MD is licensed under CC BY-SA 3.0 for an image of a patient with impaired mobility who developed a DVT. Table 13.2a Effects of Immobility on Body SystemsSkalsky, A. J., & McDonald, C. M. (2012). Prevention and management of limb contractures in neuromuscular diseases. Physical Medicine and Rehabilitation Clinics of North America, 23(3), 675–687. https://doi.org/10.1016/j.pmr.2012.06.009 \| Body System \| Immobility Effects \| Potential Complications \| \|---\|---\|---\| \| Psychological \| Depression Anxiety Distress \| Decreased quality of life \| \| Cardiovascular \| Decreased systemic vascular resistance causing venous pooling in extremities Decreased cardiac output \| Orthostatic hypotension Thrombus formation \| \| Respiratory \| Decreased strength of respiratory muscles Diminished lung expansion Hypoventilation Impaired gas exchange Decreased cough reflex Pulmonary secretion pooling Blood redistribution and fluid shifts within the lung tissues \| Atelectasis Hypoxia Pneumonia Pulmonary edema Pulmonary embolism \| \| Integumentary \| Decreased delivery of oxygen and nutrients to tissues Tissue ischemia Inflammation over bony prominences Friction and shear \| Skin breakdown Pressure injuries Infection Abrasions \| \| Musculoskeletal \| Reduced muscle mass Decreased muscle strength Decreased endurance Shortening of connective tissue Impaired joint mobility Impaired calcium metabolism \| Fatigue Decreased stability and balance Muscle atrophy Joint contractures Foot drop Osteoporosis Falls Fractures \| \| Gastrointestinal \| Decreased peristalsis Anorexia Decreased fluid intake Increased intestinal gas Altered swallowing \| Constipation Fecal impaction Ileus Flatulence Abdominal distention Nausea and vomiting Heartburn Aspiration Malnutrition \| \| Genitourinary \| Urinary discomfort Urinary retention \| Urinary tract infection \| Read additional information pertaining to the content in Table 13.2a using the hyperlinks in the following box. - Read additional details about assessing the cardiovascular system and assessing for deep vein thrombosis (DVT) in the “Cardiovascular Assessment” chapter in Open RN Nursing Skills. - Read additional details about performing a “Respiratory Assessment” in Open RN Nursing Skills. - Read more about treating hypoxia in the “Oxygenation” chapter of this textbook. - Read about preventing pressure injuries in the “Integumentary” chapter of this textbook. - Read details about performing a “Musculoskeletal Assessment” in Open RN Nursing Skills. - Read more about constipation, impaction, ileus, urinary retention, and urinary tract infection in the “Elimination” chapter of this textbook. - Review how to perform an “Abdominal Assessment” in Open RN Nursing Skills. Strategies to promote patient mobility can be divided into two categories: those used when the patient is in bed and those used when the patient is able to get out of bed. In-bed interventions to enhance mobility include performing repositioning activities, completing range of motion exercises, and assisting the patient to dangle on the edge of a bed. Out-of-bed interventions to enhance mobility include transferring the patient from bed to chair and assisting with ambulation.American Nurses Association. (2014). Current topics in safe patient handling and mobility. American Nurse Today (supplement). https://www.myamericannurse.com/wp-content/uploads/2014/07/ant9-Patient-Handling-Supplement-821a_LOW.pdf Unfortunately, ambulation of patients has been identified as the most frequently missed element of inpatient nursing care with rates as high as 76–88% of the time.Kalisch, B., Lee, S., & Dabney, B. (2013). Outcomes of inpatient mobilisation: A literature review. Journal of Clinical Nursing 23(11-12), 1486-1501. https://doi.org/10.1111/jocn.12315 Before discussing these interventions to promote mobility, let’s review the assessments that a nurse must perform prior to safely implementing mobilization interventions. Assessing Mobility Status and the Need for Assistance A patient’s mobility status and their need for assistance affect nursing care decisions, such as handling and transferring procedures, ambulation, and implementation of fall precautions. Initial mobility assessments are typically performed on admission to a facility by a physical therapist (PT). See Table 13.2b for an example of common types of assistance required. Table 13.2b Common Types of Assistance RequiredMiller, B. (n.d.). Functional mobility and physical therapy. Capital Area Physical Therapy and Wellness. https://www.capitalareapt.com/functional-mobility-and-physical-therapy/ \| Type of Assistance Required \| Description \| \|---\|---\| \| Dependent \| The patient is unable to help at all. A mechanical lift and assistance by other personnel are required to perform tasks. \| \| Maximum Assistance \| The patient can perform 75% of the mobility task while the caregiver assists with 25%. \| \| Moderate Assistance \| The patient can perform 50% of the mobility task while the caregiver assists with 50%. \| \| Minimal Assistance \| The patient can perform 75% of the mobility task while the caregiver assists with 25%. \| \| Contact Guard Assist \| The caregiver places one or two hands on the patient’s body to help with balance but provides no other assistance to perform the functional mobility task. \| \| Stand By Assist \| The caregiver does not touch the patient or provide assistance, but remains close to the patient for safety in case they lose their balance or need help to maintain safety during the task being performed. \| \| Independent \| The patient can safely perform the functional task with no assistance on their own. \| In addition to the amount of assistance required, physical therapists may determine a patient’s weight-bearing status. For example, patients with lower extremity fractures or those recovering from knee or hip replacement often progress through stages of weight-bearing activity. See Table 13.2c for common weight-bearing prescriptions. Table 13.2c Weight-Bearing Prescriptions \| Type of Weight-Bearing \| Description \| \|---\|---\| \| Nonweight-bearing (NWB) \| The leg must not touch the floor and is not permitted to support any weight at all. Crutches or other devices are used for mobility. \| \| Toe-touch weight-bearing (TTWB) \| The foot or toes may touch the floor to maintain balance, but no weight should be placed on the affected leg. \| \| Partial weight-bearing \| A small amount of weight may be supported on the affected leg. Weight may be gradually increased to 50% of body weight, which permits the person to stand with body weight evenly supported by both feet (but not walking). \| \| Weight-bearing as tolerated \| The patient can support 50% to 100% of weight on the affected leg and can independently choose the weight supported by the extremity based on their tolerance and the circumstances. \| \| Full weight-bearing \| The leg can support 100% of a person’s body weight, which permits walking. \| In addition to reviewing orders regarding weight-bearing and assistance required, all staff should assess patient mobility before and during interventions, such as transferring from surface to surface or during ambulation. Staff may frequently rely on the patient’s or a family member’s report on the patient’s ability to stand, transfer, and ambulate, but this information can be unreliable. For example, the patient may have unrecognized physical deconditioning from the disease or injury that necessitated hospitalization, or they may have developed new cognitive impairments related to the admitting diagnosis or their current medications.American Nurses Association. (2014). Current topics in safe patient handling and mobility. American Nurse Today (supplement). https://www.myamericannurse.com/wp-content/uploads/2014/07/ant9-Patient-Handling-Supplement-821a_LOW.pdf Several objective screening tests, such as the Timed Get Up and Go Test, have traditionally been used by nurses to assess a patient’s mobility status. The Timed Get Up and Go Test begins by having the patient stand up from an armchair, walk three yards, turn around, walk back to the chair, and sit down. As the patient performs these maneuvers, their posture, body alignment, balance, and gait are analyzed. However, this test and other tests do not provide guidance on what the nurse should do if the patient can’t maintain seated balance, bear weight, or stand and walk. The Banner Mobility Assessment Tool (BMAT) was developed to provide guidance regarding safe patient handling and mobility (SPHM). It is used as a nurse-driven bedside assessment of patient mobility and walks the patient through a four-step functional task list and identifies the mobility level the patient can achieve. It then provides guidance regarding the SPHM technology needed to safely lift, transfer, and mobilize the patient.American Nurses Association. (2014). Current topics in safe patient handling and mobility. American Nurse Today (supplement). https://www.myamericannurse.com/wp-content/uploads/2014/07/ant9-Patient-Handling-Supplement-821a_LOW.pdf Read additional information about the Banner Mobility Assessment Tool (BMAT) using the following hyperlink. See the following box for an example of a nurse using the BMAT. Example of Banner Mobility Assessment Tool In ActionAmerican Nurses Association. (2014). Current topics in safe patient handling and mobility. American Nurse Today (supplement). https://www.myamericannurse.com/wp-content/uploads/2014/07/ant9-Patient-Handling-Supplement-821a_LOW.pdf A 65-year-old male was admitted to the hospital late in the evening. He is 6’2″ tall and weighs 350 lbs. (158 kg). He needed to have a bowel movement but didn’t want to use a bedpan. The nurse wasn’t comfortable getting him up to use the bathroom because he hadn’t yet been evaluated by physical therapy, and a physical therapist wasn’t available until the following morning. Per agency policy, the nurse used the BMAT and determined the patient was currently at Mobility Level 3. He was transferred to the toilet using a nonpowered stand aid. Both the patient and nurse were relieved and satisfied with the outcome. Safe Patient Handling Assisting patients with decreased immobility poses an increased risk of injury to health care workers. A focus on safe patient handling and mobility (SPHM) in acute and long-term care over the past decade has resulted in decreased staff lifting injuries for the first time in 30 years. Nonetheless, nurses still suffer more musculoskeletal disorders from lifting than other employees in the manufacturing and construction industries. Many employers and nurses previously believed that lifting injuries could be prevented by using proper body mechanics, but evidence contradicts this assumption. Body mechanics involves the coordinated effort of muscles, bones, and one’s nervous system to maintain balance, posture, and alignment when moving, transferring, and positioning patients.This work is a derivative of Clinical Procedures for Safer Patient Care by British Columbia Institute of Technology and is licensed under CC BY 4.0 The National Institute of Occupational Safety and Health (NIOSH) calculates maximum loads for lifting, pushing, pulling, and carrying for all types of employees. For example, a maximum load for employees lifting a box with handles is 50 pounds (23 kg), but this weight is decreased when the lifter has to reach, lift from near the floor, or assume a twisted or awkward position. Because patients don’t come in simple shapes and may sit or lie in awkward positions, move unexpectedly, or have wounds or devices that interfere with lifting, the safe lifting load for patients is less than this maximum 50 pound load. Although using proper body mechanics and good lifting techniques are important, they don’t prevent lifting injuries in these patient circumstancesThis work is a derivative of Clinical Procedures for Safer Patient Care by British Columbia Institute of Technology and is licensed under CC BY 4.0,American Nurses Association. (2014). Current topics in safe patient handling and mobility. American Nurse Today (supplement). https://www.myamericannurse.com/wp-content/uploads/2014/07/ant9-Patient-Handling-Supplement-821a_LOW.pdf,National Institute for Occupational Safety and Health. (2013, August 2). Safe patient handling and mobility (SPHM). Centers for Disease Control and Prevention. https://www.cdc.gov/niosh/topics/safepatient/default.html Factors that increase risk for lifting injuries in nurses are exertion, frequency, posture, and duration of exposure. Combinations of these factors, such as high exertion while in an awkward posture (for example, holding a patient’s leg while bent over and twisted), unpredictable patient movements, and extended reaching, intensify the risk.Francis, R., & Dawson, M. (2016) Safe patient handling and mobility: The journey continues. American Nurse Today, 11(5). https://www.myamericannurse.com/wp-content/uploads/2016/05/Patient-Handling-Safety-426b.pdf In 2013 the American Nurses Association (ANA) published Safe Patient Handling and Mobility (SPHM) standards. See the standards in the following box. Learn more about safe patient handling using the following hyperlinks. View ANA videos on safe patient handling: Preventing Nurse Injuries and ANA Presents Safe Patient Handling and Mobility. Read an ANA article on Safe Patient Handling – The Journey Continues. ANA Standards for Safe Patient Handling and MobilityAmerican Nurses Association. (2014). Current topics in safe patient handling and mobility. American Nurse Today (supplement). https://www.myamericannurse.com/wp-content/uploads/2014/07/ant9-Patient-Handling-Supplement-821a_LOW.pdf Standard 1: Establish a culture of safety. This standard calls for the employer to establish a commitment to a culture of safety. This means prioritizing safety over competing goals in a blame-free environment where individuals can report errors or incidents without fear. The employer is compelled to evaluate systemic issues that contribute to incidents or accidents. The standard also calls for safe staffing levels and improved communication and collaboration. Every organization should have a procedure for nurses to report safety concerns or refuse an assignment due to concern about patients’ or their own safety. Standard 2: Implement and sustain an SPHM program. This standard outlines SPHM program components, including patient assessment and written guidelines for safe patient handling by staff. Standard 3: Incorporate ergonomic design principles to provide a safe care environment. This standard is based on the concept of prevention of injuries through ergonomic design that considers the physical layout, work-process flow, and use of technology to reduce exposure to injury or illness. Standard 4: Select, install, and maintain SPHM technology. This standard provides guidance in selecting, installing, and maintaining SPHM technology. Standard 5: Establish a system for education, training, and maintaining competence. This standard outlines SPHM training for employees, including the demonstration of competency before using SPHM technology with patients. Standard 6: Integrate patient-centered SPHM assessment, plan of care, and use of SPHM technology. This standard focuses on the patient’s needs by establishing assessment guidelines and developing an individual plan of care. It outlines the importance of using SPHM technology in a therapeutic manner with the goal of promoting patients’ independence. For example, a patient may need full-body lift technology immediately after surgery, then progress to a sit-to-stand lift for transfers, and then progress to a technology that supports ambulation. Standard 7: Include SPHM in reasonable accommodation and post-injury return to work. This standard promotes an employee’s return to work after an injury. Standard 8: Establish a comprehensive evaluation system. The final standard calls for evaluation of outcomes related to an agency’s implementation of a SPHM program with remediation of deficiencies. Assistive Devices There are several types of assistive devices that a nurse may incorporate during safe patient handling and mobility. An assistive device is an object or piece of equipment designed to help a patient with activities of daily living, such as a walker, cane, gait belt, or mechanical lift.Agency for Healthcare Research and Quality. (2019, September). Never events. Patient Safety Network. https://psnet.ahrq.gov/primer/never-events Assistive devices include other items described below. Gait Belts Gait belts should be used to ensure stability when assisting patients to stand, ambulate, or transfer from bed to chair. A gait belt is a 2-inch-wide (5 mm) belt, with or without handles, that is placed around a patient’s waist and fastened with a buckle. The gait belt should be applied on top of clothing or a gown to protect the patient’s skin. See Figure 13.3“GaitBelt.jpg” by unknown author is licensed under CC BY 4.0. Access for free at https://opentextbc.ca/clinicalskills/chapter/3-2-body-mechanics/ for an image of a gait belt. Slider Boards A slider board (also called a transfer board) is used to transfer an immobile patient from one surface to another while the patient is lying supine (e.g., from a stretcher to hospital bed).This work is a derivative of Clinical Procedures for Safer Patient Care by British Columbia Institute of Technology and is licensed under CC BY 4.0 See Figure 13.4“SliderBoard2-1.jpg” by unknown author is licensed under CC BY 4.0. Access for free at https://opentextbc.ca/clinicalskills/chapter/3-7-transfers-and-ambulation/ for an image of a patient being transferred by logrolling off a slider board with several assistants. Sit to Stand Lifts Sit to Stand Lifts (also referred to as Sara Lifts, Lift Ups, Stand Assist, or Stand Up Lifts) are mobility devices that assist weight-bearing patients who are unable to transition from a sitting position to a standing position using their own strength. They are used to safely transfer patients who have some muscular strength but not enough strength to safely change positions by themselves. Some sit to stand lifts use a mechanized lift whereas others are nonmechanized. See Figure 13.5“invacare-reliant-350-electric-sit-to-stand-lift-3.jpg” by Invacare. This image is included on the basis of Fair Use. for an image of a nurse assisting a patient to stand with a sit to stand lift. Mechanical Lifts A mechanical lift is a hydraulic lift with a sling used to move patients who cannot bear weight or have a medical condition that does not allow them to stand or assist with moving. It can be a portable device or permanently attached to the ceiling. See Figure 13.6“molift_air_200_rgosling_mb_env_585707.jpg” by unknown author, courtesy of etac. This image is included on the basis of Fair Use. for an image of a mechanical lift. Early Mobility Protocols Many hospitals use nurse-driven mobility protocols to encourage early mobility of patients in intensive care units and after surgery. The purpose of early mobility protocols is to maintain the patient’s baseline mobility and functional capacity, decrease the incidence of delirium, and decrease hospital length of stay. Protocols include a coordinated approach by the multidisciplinary team and may include respiratory therapists, physical therapists, pharmacists, occupational therapists, and the health care provider who focus on getting the patient out of bed faster.Agency for Healthcare Research and Quality. (2017, January). Nurse-driven early mobility protocols: Facilitator guide. https://www.ahrq.gov/hai/tools/mvp/modules/technical/nurse-early-mobility-protocols-fac-guide.html When early mobility protocols are in place, nurses use a screening tool to determine whether a patient is clinically ready to attempt the protocol. This algorithm begins by reviewing the patient’s neurological criteria, such as, does the patient open his or her eyes in response to verbal stimulation? If the patient meets neurological criteria, they are assessed against additional criteria for respiratory, circulatory, neurological, and other considerations. If the patient clears these criteria, a registered nurse may carefully initiate an early mobilization protocol in collaboration with a physical therapist. See Figure 13.7This work is derived from Nurse-Driven Early Mobility Protocols: Facilitator Guide. Content last reviewed January 2017. Agency for Healthcare Research and Quality, Rockville, MD. Access for free at https://www.ahrq.gov/hai/tools/mvp/modules/technical/nurse-early-mobility-protocols-fac-guide.html for an example of an early mobilization protocol used for patients in an ICU.Agency for Healthcare Research and Quality. (2017, January). Nurse-driven early mobility protocols: Facilitator guide. https://www.ahrq.gov/hai/tools/mvp/modules/technical/nurse-early-mobility-protocols-fac-guide.html See the following box for an example of a mobilization protocol in an intermediate care unit. Example of Early Mobilization ProtocolAgency for Healthcare Research and Quality. (2017, January). Nurse-driven early mobility protocols: Facilitator guide. https://www.ahrq.gov/hai/tools/mvp/modules/technical/nurse-early-mobility-protocols-fac-guide.html Here is an example of using an early mobilization protocol in an intermediate care unit with patient care technicians (PCT). Three PCTs collaborate with nurses from 7 a.m. to 7 p.m. Each PCT has eight patients and is responsible for mobilizing patients during each 12-hour shift. Each patient care technician discusses each patient’s level of activity with the RN at the beginning of the shift and determines how many times each patient will be mobilized throughout the day. Any concerns that arise during mobilization are shared with the nurse for appropriate follow-up. Range of Motion Exercises When patients are unable to ambulate or have injury to specific extremities, range of motion (ROM) exercises are often prescribed. ROM exercises facilitate movement of specific joints and promote mobility of the extremities. Because changes in joints can occur after three days of immobility, ROM exercises should be started as soon as possible. There are three types of ROM exercises: passive, active, and active assist. Passive range of motion is movement applied to a joint solely by another person or by a passive motion machine. When passive range of motion is applied, the joint of an individual receiving exercise is completely relaxed while the outside force moves the body part while they are lying in bed. For example, patients who undergo knee replacement surgery may be prescribed a passive motion machine that continuously flexes and extends the patient’s knee while lying in bed. See Figure 13.8 “Continuous_Passive_Motion_Machine.jpg” by User:Ravedave is licensed under CC BY-SA 3.0 for an image of a passive motion machine. Active range of motion is movement of a joint by the individual performing the exercise with no outside force aiding in the movement. Active assist range of motion is joint movement with partial assistance from an outside force. For example, during the recovery period after shoulder surgery, a patient attends physical therapy and receives 50% assistance in moving the arm with the help of a physical therapy assistant. View an infographic demonstrating range of motion exercises. Patients may receive temporary ROM exercises due to injury, surgery, or other temporary conditions. These patients are expected to make a full recovery and over time will no longer need ROM to ensure the proper functioning of their joint. Other patients require long-term ROM exercises to prevent contractures that can occur in conditions such as spinal cord injury, stroke, neuromuscular diseases, or traumatic brain injury. A contracture is the lack of full passive range of motion due to joint, muscle, or soft tissue limitations.Skalsky, A. J., & McDonald, C. M. (2012). Prevention management of limb contractures in neuromuscular diseases. Physical Medicine and Rehabilitation Clinics of North America, 23(3), 675-687. https://dx.doi.org/10.1016%2Fj.pmr.2012.06.009 See Figure 13.9“Muscle_contractures_of_young_man.jpg” by Maria Sieglinda von Nudeldorf is licensed under CC BY-SA 4.0 for an image of a severe leg contracture in a patient with a terminal neurological condition. Range of motion exercises are prescribed by a physical therapist and can be performed by physical therapy assistants, nursing assistants, patient technicians, and nurses based on agency policy. Guidelines for performing range of motion exercises include the following: - A program of passive stretching should be started as early as possible in the course of neuromuscular disease to prevent contractures and become part of a regular morning and evening routine. - Proper technique is essential for passive stretching to be effective. With each stretch, the position should be held for a count of 15, and each exercise should be repeated 10 to 15 times during a session (or as prescribed). Stretching should be performed slowly and gently. An overly strenuous stretch may cause discomfort and reduce cooperation. - Written instructional materials should be provided to the patient and family as a supplement to verbal instructions and demonstrations by the physical therapist. Watch a YouTube video demonstration of passive motion exercises.Mayo Clinic. (2020, March 30). Passive motion exercises. [Video]. YouTube. All rights reserved. https://youtu.be/EjJ5nX_jM-w Limb positioning with assistive devices can also be used to prevent contracture formation. The limb should be placed in a resting position that opposes or minimizes flexion.Skalsky, A. J., & McDonald, C. M. (2012). Prevention management of limb contractures in neuromuscular diseases. Physical Medicine and Rehabilitation Clinics of North America, 23(3), 675-687. https://dx.doi.org/10.1016%2Fj.pmr.2012.06.009 Positioning aids include pillows, foot boots, handrolls, hand-wrist splints, heel or elbow protectors, abduction pillows, or a trapeze bar. See Figure 13.10 “AFO_Ankle_Foot_Orthosis_Orthotic_Brace.JPG” by Pagemaker787 is licensed under CC BY-SA 4.0 for an image of a brace used to prevent foot drop in a patient with multiple sclerosis. Foot drop is a complication of immobility that results in plantar flexion of the foot, interfering with the ability to complete weight bearing activities. Read additional information about range of motion exercises, preventing contractures, and physical therapy using the following hyperlinks. Review how to perform Active Range of Motion Exercises. Read how to Prevent and Manage Contractures. Read more details about Physical Therapy. Repositioning Patients Repositioning a bedridden patient maintains body alignment and prevents pressure injuries, foot drop, and contractures. Proper positioning also provides comfort for patients who have decreased mobility related to a medical condition or treatment. When repositioning a patient in bed, supportive devices such as pillows, rolls, and blankets can aid in providing comfort and safety. There are several potential positions that are determined based on the patient’s medical condition, preferences, or treatment related to an illness.This work is a derivative of Clinical Procedures for Safer Patient Care by British Columbia Institute of Technology and is licensed under CC BY 4.0 It is important to reposition patients appropriately to prevent neurological injury that can occur if a patient is inadvertently placed on their arm. Supine Position In supine positioning, the patient lies flat on their back. Pillows or other devices may be used to prevent foot drop. Additional supportive devices, such as pillows under the arms, may be added for comfort. See Figure 13.11“supine.jpg” by unknown author is licensed under CC BY 4.0. Access for free at https://opentextbc.ca/clinicalskills/chapter/3-4-positioning-a-patient-in-bed/ for an image of a patient in the supine position.This work is a derivative of Clinical Procedures for Safer Patient Care by British Columbia Institute of Technology and is licensed under CC BY 4.0 Prone Position In prone positioning, the patient lies on their stomach with their head turned to the side.This work is a derivative of Clinical Procedures for Safer Patient Care by British Columbia Institute of Technology and is licensed under CC BY 4.0 Pillows may be placed under the lower legs to align the feet. See Figure 13.12“prone.jpg” by unknown author is licensed under CC BY 4.0. Access for free at https://opentextbc.ca/clinicalskills/chapter/3-4-positioning-a-patient-in-bed/ for an image of a patient in the prone position. Placing patients in the prone position may improve their oxygenation status in certain types of medical disorders, such as COVID-19.Shelhamer, M., Wesson, P., Solari, I. L., Jensen, D. L., Steele, W. A., Dimitrov, V. G., Kelly, J. D., Aziz, S., Gutierrez, V. P., Vittinghoff, E., Chung, K. K., Menon, V. P., Ambris, H. A., & Baxi, S. M.(2021). Prone positioning in moderate to severe acute respiratory distress syndrome due to COVID-19: A cohort study and analysis of physiology. Journal of Intensive Care Medicine, 36(2), 241-252. https://doi.org/10.1177%2F0885066620980399 Lateral Position In lateral positioning, the patient lies on one side of their body with the top leg flexed over the bottom leg. This position helps relieve pressure on the coccyx.This work is a derivative of Clinical Procedures for Safer Patient Care by British Columbia Institute of Technology and is licensed under CC BY 4.0 A pillow may be placed under the top arm for comfort. See Figure 13.13“lateral.jpg” by unknown author is licensed under CC BY 4.0. Access for free at https://opentextbc.ca/clinicalskills/chapter/3-4-positioning-a-patient-in-bed/ for an image of a patient in the lateral position. The lateral position is often used for pregnant women to prevent inferior vena cava compression and enhance blood flow to the fetus. Sims Position In Sims positioning, the patient is positioned halfway between the supine and prone positions with their legs flexed. A pillow is placed under the top leg. Their arms should be comfortably placed beside them, not underneath.This work is a derivative of Clinical Procedures for Safer Patient Care by British Columbia Institute of Technology and is licensed under CC BY 4.0 See Figure 13.14“sims.jpg” by unknown author is licensed under CC BY 4.0. Access for free at https://opentextbc.ca/clinicalskills/chapter/3-4-positioning-a-patient-in-bed/ for an image of a patient in Sims position. The Sims position is used during some procedures, such as the administration of an enema. Fowler’s Position In Fowler’s positioning, the head of bed is placed at a 45- to 90-degree angle. The bed can be positioned to slightly flex the hips to help prevent the patient from migrating downwards in bed.This work is a derivative of Clinical Procedures for Safer Patient Care by British Columbia Institute of Technology and is licensed under CC BY 4.0 See Figure 13.15“degreeLow.jpg” by unknown author is licensed under CC BY 4.0. Access for free at https://opentextbc.ca/clinicalskills/chapter/3-4-positioning-a-patient-in-bed/ for an image of a patient in Fowler’s position. High Fowler’s position refers to the bed being at a 90-degree angle. The Fowler’s position is used to promote lung expansion and improve a patient’s oxygenation. It is also used to prevent aspiration in patients while eating or receiving tube feeding. Semi-Fowler’s Position In Semi-Fowler’s positioning, the head of bed is placed at a 30- to 45-degree angle. The patient’s hips may or may not be flexed. See Figure 13.16“degreeSemi.jpg” by unknown author is licensed under CC BY 4.0. Access for free at https://opentextbc.ca/clinicalskills/chapter/3-4-positioning-a-patient-in-bed/ for an image of a patient in Semi-Fowler’s position. Semi-Fowler’s position is used for the same purposes as Fowler’s position but is generally better tolerated over long periods of time. Trendelenburg Position In Trendelenburg positioning, the head of the bed is placed lower than the patient’s feet. This position may be used in certain situations to promote venous return to the head and heart, such as during severe hypotension and medical emergencies.This work is a derivative of Clinical Procedures for Safer Patient Care by British Columbia Institute of Technology and is licensed under CC BY 4.0 See Figure 13.17“Sept-22-2015-097.jpg” by unknown author is licensed under CC BY 4.0. Access for free at https://opentextbc.ca/clinicalskills/chapter/3-4-positioning-a-patient-in-bed/ for an image of Trendelenburg position. Tripod Position Patients who are feeling short of breath often naturally assume the tripod position. In the tripod position, the patient leans forward while sitting with their elbows on their knees or resting on a table. Patients experiencing breathing difficulties can be placed in this position to enhance lung expansion and air exchange. See Figure 13.18“Tripod_position.png” by Nic Ashman, Chippewa Valley Technical College is licensed under CC BY 4.0 for images of an individual demonstrating breathing difficulty who has assumed the tripod position. Moving a Patient Up in Bed When moving a patient up in bed, first determine the level of assistance needed to provide optimal patient care. It is vital to prevent friction and shear when moving a patient up in bed to prevent pressure injuries. If a patient is unable to assist with repositioning in bed, follow agency policy regarding using lifting devices and mechanical lifts. If the patient is able to assist with repositioning and minimal lifting by staff is required, use the following guidelines with assistance from another health care professional to help with the move and prevent injury.This work is a derivative of Clinical Procedures for Safer Patient Care by British Columbia Institute of Technology and is licensed under CC BY 4.0 See Figure 13.19“Book-pictures-2015-572.jpg” by unknown author is licensed under CC BY 4.0. Access for free at https://opentextbc.ca/clinicalskills/chapter/3-5-positioning-a-patient-on-the-side-of-a-bed/ for an image of moving a patient up in bed. - Explain to the patient what will happen and how the patient can help. - Raise the bed to a safe working height and ensure that the brakes are applied. - Position the patient in the supine position with the bed flat. Place a pillow at the head of the bed and against the headboard to prevent accidentally bumping the patient’s head on the headboard. - Two health care professionals should stand with feet shoulder width apart between the shoulders and hips of the patient at the bedside. This keeps the heaviest part of the patient closest to the center of gravity of the health care providers. Weight will be shifted from back foot to front foot. - Fan-fold the draw sheet toward the patient with palms facing up. This provides a strong grip to move the patient up with the draw sheet. - Ask the patient to tilt their head toward their chest, fold arms across their chest, and bend their knees to assist with the movement. Let the patient know when the move will happen. This step prevents injury from occurring to the patient and prepares them for the move. Face the direction of movement. Proper body mechanics can help prevent back injury when used in appropriate patient care situations. - On the count of three by the lead person, gently slide (not lift) the patient up the bed, shifting your weight from the back foot to the front, keeping your back straight and knees slightly bent. - Replace the pillow under the patient’s head, reposition the patient in the bed, and cover them with a sheet or blanket to provide comfort. - Lower the bed, raise the side rails as indicated, and ensure the call light is within reach. Perform hand hygiene.This work is a derivative of Clinical Procedures for Safer Patient Care by British Columbia Institute of Technology and is licensed under CC BY 4.0 Assisting Patients to Seated Position Prior to ambulating, repositioning, or transferring a patient from one surface to another (e.g., a bed to a wheelchair), it often necessary to move the patient to the side of the bed to avoid straining or excessive reaching by the health care professional. Positioning the patient to the side of the bed also allows the health care provider to have the patient as close as possible to their center of gravity for optimal balance during patient handling.This work is a derivative of Clinical Procedures for Safer Patient Care by British Columbia Institute of Technology and is licensed under CC BY 4.0 Patients who have been lying in bed may experience vertigo, a sensation of dizziness as if the room is spinning, or orthostatic hypotension, low blood pressure that occurs when a patient changes position from lying to sitting or sitting to standing and causes the patient to feel dizzy, faint, or light-headed. Orthostatic hypotension is defined as a drop in systolic blood pressure of 20 mm Hg or more or a drop of diastolic blood pressure of 10 mm Hg or more within 3 minutes of sitting or standing. For this reason, always begin a transfer or ambulation process by sitting the patient on the side of the bed for a few minutes with their legs dangling.This work is a derivative of Clinical Procedures for Safer Patient Care by British Columbia Institute of Technology and is licensed under CC BY 4.0 Begin by explaining to the patient what will happen and how they can help. Determine if additional assistance or a mechanical lift is needed.This work is a derivative of Clinical Procedures for Safer Patient Care by British Columbia Institute of Technology and is licensed under CC BY 4.0 Ensure the bed is in a low and locked position, and then use the following guidelines to assist a patient to the seated position on the edge of the bed.This work is a derivative of Clinical Procedures for Safer Patient Care by British Columbia Institute of Technology and is licensed under CC BY 4.0 See Figure 13.20“Book-pictures-2015-5851.jpg,” “Book-pictures-2015-587.jpg,” and “Book-pictures-2015-588.jpg” by unknown authors are licensed under CC BY 4.0. Access for free at https://opentextbc.ca/clinicalskills/chapter/3-5-positioning-a-patient-on-the-side-of-a-bed/ for images of a nurse assisting a patient to a seated position. - Stand facing the head of the bed at a 45-degree angle with your feet apart, with one foot in front of the other. Stand next to the waist of the patient. - Ask the patient to turn onto their side, facing you, as they move closer to the edge of the bed. - Place one hand behind the patient’s shoulders, supporting the neck and vertebrae. - On the count of three, instruct the patient to use their elbows to push up against the bed and then grasp the side rail as you support their shoulders as they sit. Shift your weight from the front foot to the back foot as you assist them to sit. Do not allow the patient to place their arms around your shoulders because this can lead to serious back injuries. - As you shift your weight, gently grasp the patient’s outer thighs with your other hand and help them slide their feet off the bed to dangle or touch the floor. This step helps the patient sit and move their legs off the bed at the same time. - Assess the patient for symptoms of orthostatic hypotension or vertigo. If they are experiencing any dizziness, request them to sit and dangle on the edge of the bed and determine if the symptoms resolve before transferring or ambulating.This work is a derivative of Clinical Procedures for Safer Patient Care by British Columbia Institute of Technology and is licensed under CC BY 4.0 Ambulating a Patient Ambulation is the ability of a patient to safely walk independently, with assistance from another person, or with an assistive device, such as a cane, walker, or crutches. After a patient has been assessed and determined safe to ambulate, determine if assistive devices or the assistance of a second staff member is required. Assist the patient to sit on the side of the bed and assess for symptoms of vertigo or orthostatic hypotension before proceeding. Ensure the patient is wearing proper footwear, such as shoes or nonslip socks. Apply a gait belt snugly over their clothing and around their waist if any type of assistance is required. See Figure 13.21“Sept-22-2015-119.jpg” and “Sept-22-2015-121-001.jpg” by unknown authors are licensed under CC BY 4.0. Access for free at https://opentextbc.ca/clinicalskills/chapter/3-5-positioning-a-patient-on-the-side-of-a-bed/ for an image of applying a gait belt. The patient should be cooperative, able to bear weight on their own, have good trunk control, and be able to transition to a standing position on their own. If these criteria are not met, then mechanical devices, such as a sit to stand lift, should be used to assist a weight-bearing patient from a sitting position to a standing position. If a patient uses a walker or cane, these assistive devices should be placed near the bed before beginning this procedure. Stand in front of the patient, with your legs on the outside of their legs. Grasp each side of the gait belt, while keeping your back straight and knees bent, and then rock your weight backwards while gently steadying the patient into a standing position. After the patient is standing and feels stable, move to their unaffected side and grasp the gait belt in the middle of their back.This work is a derivative of Clinical Procedures for Safer Patient Care by British Columbia Institute of Technology and is licensed under CC BY 4.0 If needed for stability, place one arm under the patient’s arm, gently grasp their forearm, and lock your arm firmly under the patient’s axilla. In this position, if the patient starts to fall, you can provide support at the patient’s shoulder.Moroz, A. (2017, June). Physical therapy (PT). Merck Manual Professional Version. https://www.merckmanuals.com/professional/special-subjects/rehabilitation/physical-therapy-pt If the patient uses a walker or cane, ensure the patient is using this device before beginning ambulation. See Figure 13.22“Sept-22-2015-122-e1443986200821.jpg,” “Sept-22-2015-124.jpg,” and “Sept-22-2015-128.jpg” by unknown authors are licensed under CC BY 4.0. Access for free at https://opentextbc.ca/clinicalskills/chapter/3-5-positioning-a-patient-on-the-side-of-a-bed/ for an image of a nurse assisting the patient to stand. Before stepping away from the bed, ask the patient if they feel dizzy or light-headed. If they do, sit the patient back down on the bed until the symptoms resolve. If the patient feels stable, begin walking by matching your steps to the patient’s. Instruct the patient to look ahead and lift each foot off the ground. Walk only as far as the patient can tolerate without feeling dizzy or weak. Periodically ask them how they are feeling to check for dizziness or weakness.This work is a derivative of Clinical Procedures for Safer Patient Care by British Columbia Institute of Technology and is licensed under CC BY 4.0 In some situations of early ambulation, it is helpful for a second staff member to follow behind the patient with a wheeled walker or wheelchair in case the patient needs to sit while walking. To assist the patient back into the bed or a chair, have them stand with the back of their knees touching the bed or chair. Grasp the gait belt and assist them as they lower into a sitting position, keeping your back straight and knees bent. Remove the gait belt. If the patient is returning to bed, place the bed in the lowest position, raise the side rails as indicated, and ensure the call light is within reach. Cover the patient with a sheet or blanket to provide comfort. Document the length of ambulation and the patient’s tolerance of ambulation. Transfer From Bed to Chair or Wheelchair Patients often require assistance when moving from a bed to a chair or wheelchair. A patient must be cooperative and predictable, able to bear weight on both legs, and able to take small steps and pivot to safely transfer with a one-person assist. If any of these criteria are not met, a two-person transfer or mechanical lift is recommended. Always complete a mobility assessment and check the provider’s or physical therapist’s orders prior to transferring patients.This work is a derivative of Clinical Procedures for Safer Patient Care by British Columbia Institute of Technology and is licensed under CC BY 4.0 Begin by explaining to the patient what will happen during the transfer and how they can help. Be sure proper footwear is in place. Lower the bed; set it at a 45-degree angle. Place the wheelchair next to the bed and apply the wheelchair brakes. If the patient has weakness on one side, place the wheelchair on their strong side.This work is a derivative of Clinical Procedures for Safer Patient Care by British Columbia Institute of Technology and is licensed under CC BY 4.0 Assist the patient to a seated position on the side of the bed with their feet on the floor. (See the previous section on how to assist a patient to a seated position.) Apply the gait belt snugly around their waist. Place your legs on the outside of their legs. Ask them to place their hands on your waist as they raise themselves into a standing position. Do not lift the patient. If additional assistance is required, obtain a mechanical lift, such as a sit to stand device. Do not allow them to put their arms around your neck because this can cause back injury. Stay close to the patient during the transfer to keep the patient’s weight close to your center of gravity. Once standing, ask the patient to pivot and then take a few steps back until they can feel the wheelchair on the back of their legs. Have the patient grasp the arm of the wheelchair and lean forward slightly. Assist the patient to lower themselves, while shifting your weight from your back leg to the front leg with your knees bent, trunk straight, and elbows slightly bent. Allow the patient to slowly lower themselves into the wheelchair using the armrests for support. See Figure 13.23“Book-pictures-2015-603.jpg” and “Book-pictures-2015-6041” by unknown authors are licensed under CC BY 4.0. Access for free at https://opentextbc.ca/clinicalskills/chapter/3-7-transfers-and-ambulation/for an image of a staff member assisting a patient to a wheelchair. Reflective Question: What could be improved during this transfer? Lowering A Patient to the Floor A patient may begin to fall while ambulating or while being transferred from one surface to another. If a patient begins to fall from a standing position, do not attempt to stop the fall or catch the patient because this can cause back injury. Instead, try to control their fall by lowering them to the floor.This work is a derivative of Clinical Procedures for Safer Patient Care by British Columbia Institute of Technology and is licensed under CC BY 4.0 If a patient starts to fall and you are close by, move behind the patient and take one step back. Support the patient around the waist or hip area or grab the gait belt. Bend one leg and place it between the patient’s legs. Slowly slide the patient down your leg, lowering yourself to the floor at the same time. Always protect their head first. Once the patient is on the floor, assess the patient for injuries prior to moving them. Assess the patient’s need for assistance to get off the floor. If the patient is unable to get up off the floor, use a mechanical lift. Complete an incident report and follow up according to the patient’s condition and agency policy. See Figure 13.24“Sept-22-2015-132-001.jpg” and “Sept-22-2015-133.jpg” by unknown authors are licensed under CC BY 4.0. Access for free at https://opentextbc.ca/clinicalskills/chapter/3-7-fall-prevention/ for images of lowering a patient to the floor. Preventing Falls Falls are a major safety concern in health care. Nurses are responsible for identifying, managing, and eliminating potential fall hazards for patients. All patient-handling activities (positioning, transfers, and ambulation) pose a risk to both patients and health care professionals. Older adults are often at increased risk for falls due to impaired mental status, decreased strength, impaired balance and mobility, and decreased sensory perception. Patients may also be at risk for falls due to gait problems, cognitive ability, visual problems, urinary frequency, generalized weakness, cognitive impairments, or medications that may cause hypotension or drowsiness.This work is a derivative of Clinical Procedures for Safer Patient Care by British Columbia Institute of Technology and is licensed under CC BY 4.0 Falls can cause head injuries, fractures, lacerations, and other injuries. Fall prevention is key. If a patient begins to feel dizzy while ambulating or transferring, assist them to sit on a chair or on the floor to avoid a fall. The head is the most important part of the body, so protect it as much as possible. In the event of a fall, seek help and stay with the patient until assistance arrives. Follow agency policy for reporting, assessing, and documenting. After a fall, always assess a patient for injuries prior to moving them. If the patient remains weak or dizzy, do not attempt to ambulate them, but instead, ask for assistance to transfer them to a chair or bed.This work is a derivative of Clinical Procedures for Safer Patient Care by British Columbia Institute of Technology and is licensed under CC BY 4.0 All patients should be assessed for risk factors for falls and necessary fall precautions implemented per agency policy. Read more information about preventing falls in the “Safety” chapter. 13.3 Applying the Nursing Process Open Resources for Nursing (Open RN) Assessment Because mobility issues are directly related to musculoskeletal disorders, perform a thorough assessment of the musculoskeletal system and its effect on the patient’s mobility status. Assess muscle strength and coordination, and then assess mobility skills in the following order: mobility in bed, dangling on the bed with supported and unsupported sitting, weight-bearing while transferring from sitting to standing or to a chair, standing and walking with assistance, and walking independently. Because immobility can negatively affect several body systems, perform a thorough assessment for patients with impaired mobility. Assess the cardiovascular system, including blood pressure, heart sounds, apical and peripheral pulses, and capillary refill time. Assess for the presence of lower extremity edema and for signs of a potential deep vein thrombosis (DVT). Assess the respiratory system, including respiratory rate, oxygen saturation, lung sounds, chest wall movement and symmetry, and depth and effort of respirations. Assess for potential signs of atelectasis and pneumonia. Assess the gastrointestinal system by inspecting for distension, auscultating bowel sounds, and palpating the abdomen for tenderness. Ask the patient about the date of their last bowel movement, and monitor stool patterns and stool characteristics. If constipation is suspected, palpate the patient’s left lower quadrant for signs of stool presence. Assess for the presence of urinary tract abnormalities related to immobility, such as suprapubic distention or tenderness that can result from urinary retention. Monitor 24-hour trend of intake and output, as well as for symptoms of dysuria, urgency, or frequency. Note if urinary incontinence is occurring due to the inability of the patient to reach the restroom in time.Skalsky, A. J., & McDonald, C. M. (2012). Prevention and management of limb contractures in neuromuscular diseases. Physical Medicine and Rehabilitation Clinics of North America, 23(3), 675–687. https://doi.org/10.1016/j.pmr.2012.06.009 Life Span Considerations At each stage of growth and development, the nurse assesses a patient’s mobility and provides appropriate education. For example, infants move their limbs, hold their head up, roll, sit, crawl, stand, and then eventually walk. Parents are educated about these developmental milestones during well-child visits. When working with school-age children, nurses provide education to prevent injury that can occur with activity, such as using helmets and knee pads to prevent injury while bicycling and skateboarding. As teenagers become adults, the nurse provides education about the effects of alcohol and other drugs on balance and safety while driving. Older adults are at increased risk for immobility. Conditions such as osteoarthritis, orthostatic hypotension, inner ear dysfunction, osteoporosis resulting in hip fractures, stroke, and Parkinson’s disease are among the most common causes of immobility in old age. Hospitalization poses a risk for altered functional status of older adults due to acute illness, decreased mobility, and the negative effects of bedrest. The American Academy of Nursing issued a recommendation in 2014 stating, “Don’t let older adults lie in bed or only get up to a chair during their hospital stay.” This recommendation highlights the importance of implementing evidence-based measures to promote activity during hospitalization to prevent functional decline in older adults.American Academy of Nursing’s Expert Panel on Acute and Critical Care. (n.d.). Reducing functional decline in older adults during hospitalization. The Hartford Institute for Geriatric Nursing, Rory Meyers College of Nursing, New York University. https://hign.org/consultgeri/try-this-series/reducing-functional-decline-older-adults-during-hospitalization Diagnoses There are several nursing diagnoses related to mobility. Review a nursing care planning source for current NANDA-I approved nursing diagnoses and interventions. A commonly used NANDA-I nursing diagnosis is Impaired Physical Mobility.Herdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York, p. 219 See Table 13.3 for the definition and selected defining characteristics of this diagnosis.Herdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York, p. 219 Table 13.3 NANDA-I Nursing Diagnosis Impaired Physical MobilityHerdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York, p. 219 \| NANDA-I Diagnosis \| Definition \| Selected Defining Characteristics \| \|---\|---\|---\| \| Impaired Physical Mobility \| Limitation in independent, purposeful movement of the body or of one or more extremities \| Alteration in gait Decrease in fine motor skills Decrease in gross motor skills Decrease in range of motion Decrease in reaction time Difficulty turning Exertional dyspnea Postural instability Uncoordinated or slow movement \| A sample nursing diagnosis in PES format is, “Impaired Physical Mobility related to decrease in muscle strength as evidenced by slow movement and alteration in gait.” Outcome Identification A sample overall goal for a patient with Impaired Physical Mobility is, “The patient will participate in activities of daily living to the fullest extent possible for their condition.” A sample SMART outcome is, “The patient will demonstrate appropriate use of adaptive equipment (e.g., a walker) for safe ambulation by the end of the shift.” Planning Interventions Nursing interventions promote a patient’s mobility and prevent effects of immobility. To avoid or minimize complications of immobility, mobilize the patient as soon as possible and to the fullest extent possible. Mobilization efforts, ranging from dangling on the edge of the bed, sitting up in a chair, and assisting with early ambulation, depend on the patient’s unique circumstances, such as their medical condition and surgery performed. For example, a patient undergoing a cardiac catheterization may be mobilized within a few hours following the procedure, whereas a patient undergoing total knee arthroplasty may begin mobilizing 24 hours following the surgery.Skalsky, A. J., & McDonald, C. M. (2012). Prevention and management of limb contractures in neuromuscular diseases. Physical Medicine and Rehabilitation Clinics of North America, 23(3), 675–687. https://doi.org/10.1016/j.pmr.2012.06.009 See details about early mobilization protocols earlier in this chapter. Encourage the patient to perform activities of daily living (ADLs) as independently as possible and participate in prescribed physical therapy. Encourage or perform active or passive range of motion exercises as prescribed by the physical therapist. Be aware that pain and fear of falling can be major deterrents to a patient’s willingness to ambulate or perform physical therapy. Monitor the patient’s level of pain by using a valid pain intensity rating scale. Administer medications if warranted and consider nonpharmacologic measures such as repositioning, splinting, and heat/cold application to reduce musculoskeletal discomfort. Encourage rest between activities. Educate the patient about appropriately using assistive devices and other fall precautions.Butcher, H., Bulechek, G., Dochterman, J., & Wagner, C. (2018). Nursing Interventions Classification (NIC). Elsevier, pp. 281-282.,Skalsky, A. J., & McDonald, C. M. (2012). Prevention and management of limb contractures in neuromuscular diseases. Physical Medicine and Rehabilitation Clinics of North America, 23(3), 675–687. https://doi.org/10.1016/j.pmr.2012.06.009 For patients at risk for developing pneumonia due to immobility, encourage adequate fluid intake to liquefy pulmonary secretions, and teach deep breathing and coughing exercises to prevent atelectasis. Monitor oxygenation levels and provide supplemental oxygen as prescribed to maintain adequate oxygenation, especially during ambulation.Skalsky, A. J., & McDonald, C. M. (2012). Prevention and management of limb contractures in neuromuscular diseases. Physical Medicine and Rehabilitation Clinics of North America, 23(3), 675–687. https://doi.org/10.1016/j.pmr.2012.06.009 For bed-bound patients, elevate the head of the bed to 30 to 45 degrees, unless medically contraindicated, and turn and reposition the patient every two hours. Perform hourly rounding to check on the patient’s needs and prevent falls. Protect the skin as needed to minimize the potential for breakdown, and advocate for devices to prevent contractures, as needed.Butcher, H., Bulechek, G., Dochterman, J., & Wagner, C. (2018). Nursing Interventions Classification (NIC). Elsevier, pp. 281-282.,Skalsky, A. J., & McDonald, C. M. (2012). Prevention and management of limb contractures in neuromuscular diseases. Physical Medicine and Rehabilitation Clinics of North America, 23(3), 675–687. https://doi.org/10.1016/j.pmr.2012.06.009 Implementing Interventions When implementing interventions to promote mobility, in addition to reviewing the current orders regarding assistance and weight-bearing, assess the patient’s current status. For example, use the Banner Mobility Assessment Tool to determine the patient’s current mobility status and needs for safe patient handling. Monitor for signs of vertigo and orthostatic hypotension and assist the patient to a sitting or lying position if they occur. Monitor vital signs before, during, and after physical activity and institute appropriate fall prevention strategies as indicated. Orthostatic hypotension is defined as a drop in systolic blood pressure of 20 mmHg or more or in diastolic blood pressure of 10 mm Hg or more within three minutes of standing. If orthostatic hypotension is suspected, measure the patient’s vital signs while he or she is supine, sitting, and standing before encouraging ambulation. Monitor and document the patient’s response to activity, such as heart rate, blood pressure, dyspnea, and skin color.Butcher, H., Bulechek, G., Dochterman, J., & Wagner, C. (2018). Nursing Interventions Classification (NIC). Elsevier, pp. 281-282.,Skalsky, A. J., & McDonald, C. M. (2012). Prevention and management of limb contractures in neuromuscular diseases. Physical Medicine and Rehabilitation Clinics of North America, 23(3), 675–687. https://doi.org/10.1016/j.pmr.2012.06.009 Evaluation Determine the patient’s progress towards their specific SMART outcomes. Encourage their participation in the setting of realistic goals for mobility and modify these goals as needed for safety. 13.4 Putting It All Together Patient Scenario Mrs. Howard is a 73-year-old woman who was recently admitted to the medical surgical floor with pneumonia. She has an underlying history of emphysema and has experienced a recent exacerbation in dyspnea during activity. This morning when being assisted to the bathroom, she reports, “I have to stop and catch my breath when walking.” Vital signs this morning indicated oxygen saturation 91% and respiratory rate 18 on room air at rest. During report it was communicated that Mrs. Howard is able to ambulate with the assistance of one but only moves short distances around the room before she needs to stop and rest. Applying the Nursing Process Assessment: The nurse identifies a relevant cue that the patient, diagnosed with pneumonia and a previous history of emphysema, is experiencing increased dyspnea when walking around the room that requires her to stop and rest. Vital signs at 0700 were reviewed, and it was noted that the patient’s respiratory rate was 24 with oxygen saturation level 91% on room air at rest. The nurse gathers additional assessment data while the patient is walking and discovers her respiratory rate increases to 30 and her oxygen saturation level decreases to 85% after walking for 2 minutes. Additionally, the patient stops and catches her breath after walking approximately 10 feet, causing her to limit her mobility. The nurse reviews the patient’s chart and finds an order for “Oxygen via nasal cannula up to 5 L/min PRN to maintain oxygen saturation at 90%.” The nurse also notes a referral for physical therapy assessment and strengthening exercises. Based on the assessment information gathered, the following nursing care plan is created for Mrs. Howard: Nursing Diagnosis: Impaired Physical Mobility r/t activity intolerance as manifested by decreased oxygen saturation, increased respirations, and patient report of “I have to stop and catch my breath while walking.” Overall Goal: The patient will demonstrate improvement in mobility. SMART Expected Outcomes: - Mrs. Howard will ambulate 50 feet in the hallway within 24 hours. - Mrs. Howard will maintain an oxygen saturation level of 90% or higher while walking within 24 hours. Planning and Implementing Nursing Interventions: The nurse plans to administer oxygen to the patient via nasal cannula as needed to maintain an oxygen saturation level of 90% or higher. The nurse will teach the patient about the importance of balancing periods of activity with periods of rest and reinforce the use of pursed-lip breathing. The nurse will encourage patient ambulation and her active participation in completing ADLs. The nurse will collaborate with physical therapy to educate the patient regarding strengthening exercises and reinforce principles of progressive exercise. The nurse plans to further assess the patient’s smoking history and promote smoking cessation. Sample Documentation At 0800 when assisting the patient to the bathroom, the patient reported, “I have to stop and catch my breath when walking.” Vital signs at 0700 were respiratory rate 24 and oxygen saturation level 91% on room air at rest. At 0830, vital signs were reassessed while the patient was walking. Her respiratory rate increased to 30 and her oxygen saturation level decreased to 85% after 2 minutes of walking. The patient stopped to catch her breath after walking approximately 10 feet. Oxygen via nasal cannula at 1 L/min was applied to the patient before ambulating in the hallway at 1000. The patient’s oxygen saturation level dropped to 88% after one minute of walking and the oxygen was increased to 2 L/min. The patient’s oxygen saturation then remained at 90% for the remainder of the walk, and she was able to ambulate 50 feet. Pursed-lip breathing was demonstrated and reinforced during the walk. Physical therapy was contacted and an assessment scheduled for later this morning. The patient reports a smoking history of a pack per day for 50 years. She is interested in stopping smoking. A smoking cessation brochure was provided and discussed. Dr. Smith was notified of these events at 1030. Evaluation Within 24 hours, Mrs. Howard successfully ambulated 50 feet in the hallway while maintaining oxygen saturation level of 90%. SMART outcomes were “met.” Planned interventions will continue. SMART outcome is revised to, “Mrs. Howard will ambulate 100 feet in the hallway within 24 hours.” 13.5 Learning Activities Open Resources for Nursing (Open RN) Learning Activities (Answers to “Learning Activities” can be found in the “Answer Key” at the end of the book. Answers to interactive activity elements will be provided within the element as immediate feedback.) Ms. Curtis is a 67-year-old patient admitted for a left total knee replacement. She is post-op Day 2 and is currently receiving care on the medical surgical unit. Ms. Curtis has been complaining of pain and refused her previous two physical therapy appointments. She agrees to sitting up in the chair, but declines walking. - What focused assessments should the nurse perform and why? - What complications could occur related to Ms. Curtis’ immobility? - What SMART outcomes should the nurse plan in collaboration with Ms. Curtis? - List interventions the nurse should plan for Ms. Curtis and their rationale. - How will the nurse evaluate if the interventions are successful? An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=2040#h5p-45 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=2040#h5p-91 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=2040#h5p-97 Mobility Case Study by Susan Jepsen for Lansing Community College are licensed under CC BY 4.0 XIII Glossary Open Resources for Nursing (Open RN) Active assist range of motion exercise: A patient’s joint receiving partial assistance in movement from an outside force. Active range of motion: Movement of a joint by the individual performing the exercise. Ambulation: The ability of a patient to safely walk independently, with assistance from another person, or with an assistive device, such as a cane, walker, or crutches. Assistive device: An object or piece of equipment designed to help a patient with activities of daily living, such as a walker, cane, gait belt, or mechanical lift. Bed mobility: The ability of a patient to move around in bed, including moving from lying to sitting and sitting to lying. Body mechanics: The coordinated effort of muscles, bones, and the nervous system to maintain balance, posture, and alignment during moving, transferring, and repositioning patients. Fowler’s position: A position where the patient is supine with the head of bed placed at a 45- to 90-degree angle. The bed can be used to slightly flex the hips to help prevent the patient from migrating downwards in bed. Functional mobility: The ability of a person to move around in their environment, including walking, standing up from a chair, sitting down from standing, and moving around in bed. Gait belt: A 2-inch-wide (5 mm) belt, with or without handles, that is fastened around a patient’s waist used to ensure stability when assisting patients to stand, ambulate, or to transfer from bed to chair. Lateral positioning: A position where the patient lies on one side of the body with the top leg over the bottom leg. This position helps relieve pressure on the coccyx. Mechanical lift: A hydraulic lift with a sling used to move patients who cannot bear weight or have a medical condition that does not allow them to stand or assist with moving. It can be a portable device or permanently attached to the ceiling. Mobility: The ability of a patient to change and control body position. Mobility exists on a continuum ranging from no impairment (i.e., the patient can make major and frequent changes in position without assistance) to being completely immobile (i.e., the patient is unable to make even slight changes in body or extremity position without assistance). Orthostatic hypotension: Low blood pressure that occurs when a patient changes position from lying to sitting or sitting to standing that causes symptoms of dizziness or light-headedness. Orthostatic hypotension is defined as a drop in systolic blood pressure of 20 mm Hg or more or a drop of diastolic blood pressure of 10 mm Hg or more within three minutes of sitting or standing. Passive range of motion exercises: Movement applied to a joint solely by another person or a passive motion machine. When passive range of motion is applied, the joint of an individual receiving exercise is completely relaxed while the outside force moves the body part. Range of motion (ROM) exercises: Activities aimed to facilitate movement of specific joints and promote mobility of extremities. Semi-Fowler’s position: A position where the head of the bed is placed at a 30- to 45-degree angle. The patient’s hips may or may not be flexed. Sims positioning: A position where the patient is positioned halfway between the supine and prone positions with their legs flexed. Sit to stand lifts: Mobility devices that assist weight-bearing patients who are unable to transition from a sitting position to a standing position by using their own strength. They are used to safely transfer patients who have some muscular strength, but not enough strength to safely change positions by themselves. Some sit to stand lifts use a mechanized lift whereas others are nonmechanized. Slider board: A board (also called a transfer board) used to transfer an immobile patient from one surface to another while the patient is lying supine (e.g., from a stretcher to hospital bed). Supine positioning: A position where the patient lies flat on their back. As the patient performs these maneuvers, their posture, alignment, balance, and gait are analyzed as the patient’s mobility status is assessed. Transferring: The action of a patient moving from one surface to another. This includes moving from a bed into a chair or moving from one chair to another. Trendelenburg position: A position where the head of the bed is placed lower than the patient’s feet. This position is used in situations such as hypotension and medical emergencies because it helps promote venous return to major organs such as the brain and heart. Tripod position: A position where the patient sits in a chair with their elbows on their knees or at the side of the bed with their arms resting on an overbed table. This position is often naturally assumed by patients with breathing difficulties. Vertigo: A sensation of dizziness as if the room is spinning. Nutrition XIV 14.1 Nutrition Introduction Open Resources for Nursing (Open RN) Learning Objectives - Describe variables that influence nutrition - Identify factors related to nutrition across the life span - Assess a patient’s nutritional status - Outline specific nursing interventions to promote nutrition - Base your decisions on the action of nutrients, signs of excess and deficiency, and specific foods associated with each nutrient - Base your decisions on the interpretation of diagnostic tests and lab values indicative of a disturbance in nutrition - Give examples of appropriate vitamin use across the life span - Identify evidence-based practices related to nutrition Nurses promote healthy nutrition to prevent disease, assist patients to recover from illness and surgery, and teach patients how to optimally manage chronic illness with healthy food choices. Healthy nutrition helps to prevent obesity and chronic diseases, such as diabetes mellitus and cardiovascular disease. By proactively encouraging healthy eating habits, nurses provide the tools for patients to maintain their health, knowing it is easier to stay healthy than to become healthy after disease sets in. When patients are recovering from illness or surgery, nurses use strategies to promote good nutrition even when a patient has a poor appetite or nausea. If a patient develops chronic disease, the nurse provides education about prescribed diets that can help manage the disease, such as a low carbohydrate diet for patients with diabetes or a low fat, low salt, low cholesterol diet for patients with cardiovascular disease. Nurses also advocate for patients with conditions that can cause nutritional deficits. For example, a nurse may be the first to notice that a patient is having difficulty swallowing at mealtime and advocates for a swallow study to prevent aspiration. A nurse may also notice other psychosocial risk factors that place a patient at risk for poor nutrition in their home environment and make appropriate referrals to enhance their nutritional status. Nurses also administer alternative forms of nutrition, such as enteral (tube) feedings or parenteral (intravenous) feedings. This chapter will review basic information about the digestive system, essential nutrients, nutritional guidelines, and then discuss the application of the nursing process to addressing patients’ nutritional status. 14.2 Nutrition Basic Concepts Open Resources for Nursing (Open RN) Before discussing assessments and interventions related to promoting good nutrition, let’s review the structure and function of the digestive system, essential nutrients, and nutritional guidelines. Digestive System The digestive system breaks down food and then absorbs nutrients into the bloodstream via the small intestine and large intestine. Because good health depends on good nutrition, any disorder affecting the functioning of the digestive system can significantly impact overall health and well-being and increase the risk of chronic health conditions. Structure and Function The gastrointestinal system (also referred to as the digestive system) is responsible for several functions, including digestion, absorption, and immune response. Digestion begins in the upper gastrointestinal tract at the mouth, where chewing of food occurs, called mastication. Mastication results in mechanical digestion when food is broken down into small chunks and swallowed. Masticated food is formed into a bolus as it moves toward the pharynx in the back of the throat and then into the esophagus. Coordinated muscle movements in the esophagus called peristalsis move the food bolus into the stomach where it is mixed with acidic gastric juices and further broken down into chyme through a chemical digestion process. As chyme is moved out of the stomach and into the duodenum of the small intestine, it is mixed with bile from the gallbladder and pancreatic enzymes from the pancreas for further digestion.This work is a derivative of Anatomy and Physiology by Boundless and is licensed under CC BY-SA 4.0 Absorption is a second gastrointestinal function. After chyme enters the small intestine, it comes into contact with tiny fingerlike projections along the inside of the intestine called villi. Villi increase the surface area of the small intestine and allow nutrients, such as protein, carbohydrates, fat, vitamins, and minerals, to absorb through the intestinal wall and into the bloodstream. Absorption of nutrients is essential for metabolism to occur because nutrients fuel bodily functions and create energy. Peristalsis moves leftover liquid from the small intestine into the large intestine, where additional water and minerals are absorbed. Waste products are condensed into feces and excreted from the body through the anus.This work is a derivative of Anatomy and Physiology by Boundless and is licensed under CC BY-SA 4.0 See Figure 14.1“Digestive-41529_1280.png” by Sarahguess5 is licensed under CC0 for labeled parts of the gastrointestinal system. In addition to digestion and absorption, the gastrointestinal system is also involved in immune function. Good bacteria in the stomach create a person’s gut biome. Gut biome contributes to a person’s immune response through antibody production in response to foreign materials, chemicals, bacteria, and other substances.Human digestive system. (2019). In Britannica. Gastrointestinal tract as an organ of immunity. https://www.britannica.com/science/human-digestive-system/The-gastrointestinal-tract-as-an-organ-of-immunity For example, patients may develop Clostridium difficile (C-diff) after taking antibiotics that kill these beneficial bacteria in the gut. Read additional details about our microbiome and immune response in the “Infection” chapter of this book. Essential Nutrients Nutrients from food and fluids are used by the body for growth, energy, and bodily processes. Essential nutrients refer to nutrients that are necessary for bodily functions but must come from dietary intake because the body is unable to synthesize them. Essential nutrients include vitamins, minerals, some amino acids, and some fatty acids.Youdim, A. (2019, May). Overview of nutrition. Merck Manual Professional Version. https://www.merckmanuals.com/professional/nutritional-disorders/nutrition-general-considerations/overview-of-nutrition Essential nutrients can be further divided into macronutrients and micronutrients. Macronutrients Macronutrients make up most of a person’s diet and provide energy, as well as essential nutrient intake. Macronutrients include carbohydrates, proteins, and fats. However, too many macronutrients without associated physical activity cause excess nutrition that can lead to obesity, cardiovascular disease, diabetes mellitus, kidney disease, and other chronic diseases. Too few macronutrients result in undernutrition, which contributes to nutrient deficiencies and malnourishment.Youdim, A. (2019, May). Overview of nutrition. Merck Manual Professional Version. https://www.merckmanuals.com/professional/nutritional-disorders/nutrition-general-considerations/overview-of-nutrition Carbohydrates Carbohydrates are sugars and starches and are an important energy source that provides 4 kcal/g of energy. Simple carbohydrates are small molecules (called monosaccharides or disaccharides) and break down quickly. As a result, simple carbohydrates are easily digested and absorbed into the bloodstream, so they raise blood glucose levels quickly. Examples of simple carbohydrates include table sugar, syrup, soda, and fruit juice. Complex carbohydrates are larger molecules (called polysaccharides) that break down more slowly, which causes slower release into the bloodstream and a slower increase in blood sugar over a longer period of time. Examples of complex carbohydrates include whole grains, beans, and vegetables.Youdim, A. (2019, May). Overview of nutrition. Merck Manual Professional Version. https://www.merckmanuals.com/professional/nutritional-disorders/nutrition-general-considerations/overview-of-nutrition Foods can also be categorized according to their glycemic index, a measure of how quickly glucose levels increase in the bloodstream after carbohydrates are consumed. The glycemic index was initially introduced as a way for people with diabetes mellitus to control their blood glucose levels. For example, processed foods, white bread, white rice, and white potatoes have a high glycemic index. They quickly raise blood glucose levels after being consumed and also cause the release of insulin, which can result in more hunger and overeating. However, foods such as fruit, green leafy vegetables, raw carrots, kidney beans, chickpeas, lentils, and bran breakfast cereals have a low glycemic index. These foods minimize blood sugar spikes and insulin release after eating, which leads to less hunger and overeating. Eating a diet of low glycemic foods has been linked to a decreased risk of obesity and diabetes mellitus. Youdim, A. (2019, May). Overview of nutrition. Merck Manual Professional Version. https://www.merckmanuals.com/professional/nutritional-disorders/nutrition-general-considerations/overview-of-nutrition See Figure 14.2“Eat-Foods-Low-on-the-Glycemic-Index-Step-1-Version-2.jpg” by unknown is licensed under CC BY-NC-SA 3.0. Access for free at https://www.wikihow.com/Eat-Foods-Low-on-the-Glycemic-Index#aiinfo for an image of the glycemic index of various foods. Proteins Proteins are peptides and amino acids that provide 4 kcal/g of energy. Proteins are necessary for tissue repair and function, growth, energy, fluid balance, clotting, and the production of white blood cells. Protein status is also referred to as nitrogen balance. Nitrogen is consumed in dietary intake and excreted in the urine and feces. If the body excretes more nitrogen than it takes in through the diet, this is referred to as a negative nitrogen balance. Negative nitrogen balance is seen in patients with starvation or severe infection. Conversely, if the body takes in more nitrogen through the diet than what is excreted, this is referred to as a positive nitrogen balance.Youdim, A. (2019, May). Overview of nutrition. Merck Manual Professional Version. https://www.merckmanuals.com/professional/nutritional-disorders/nutrition-general-considerations/overview-of-nutrition During positive nitrogen balance, excess protein is converted to fat tissue for storage. Proteins are classified as complete, incomplete, or partially complete. Complete proteins must be ingested in the diet. They have enough amino acids to perform necessary bodily functions, such as growth and tissue maintenance. Examples of foods containing complete proteins are soy, quinoa, eggs, fish, meat, and dairy products. Incomplete proteins do not contain enough amino acids to sustain life. Examples of incomplete proteins include most plants, such as beans, peanut butter, seeds, grains, and grain products. Incomplete proteins must be combined with other types of proteins to add to amino acids and form complete protein combinations.Brazier, Y. (2020, December 10). How much protein does a person need? Medical News Today. https://www.medicalnewstoday.com/articles/196279 For example, vegetarians must be careful to eat complementary proteins, such as grains and legumes, or nuts and seeds and legumes, to create complete protein combinations during their daily food intake. Partially complete proteins have enough amino acids to sustain life, but not enough for tissue growth and maintenance. Because of the similarities, most sources consider partially complete proteins to be in the same category as incomplete proteins. See Figure 14.3“Protein-rich_Foods.jpg” by Smastronardo is licensed under CC BY-SA 4.0 for an image of protein-rich foods. Fats Fats consist of fatty acids and glycerol and are essential for tissue growth, insulation, energy, energy storage, and hormone production. Fats provide 9 kcal/g of energy.Youdim, A. (2019, May). Overview of nutrition. Due to its high-energy content, a little fat goes a long way. Fats are classified as saturated, unsaturated, and trans fatty acids. Saturated fats come from animal products, such as butter and red meat (e.g., steak). Saturated fats are solid at room temperature. Recommended intake of saturated fats is less than 10% of daily calories because saturated fat raises cholesterol and contributes to heart disease.Healthwise. (2020, December 17). Types of fats. Michigan Medicine at University of Michigan. https://www.uofmhealth.org/health-library/aa160619 Unsaturated fats come from oils and plants, although chicken and fish also contain some unsaturated fats. Unsaturated fats are healthier than saturated fats. Examples of unsaturated fats include olive oil, canola oil, avocados, almonds, and pumpkin seeds. Fats containing omega-3 fatty acids are considered polyunsaturated fats and help lower LDL cholesterol levels. Fish and other seafood are excellent sources of omega-3 fatty acids. Trans fats are fats that have been altered through a hydrogenation process, so they are not in their natural state. Trans fats are found in processed foods, such as chips, crackers, and cookies, as well as in some margarines and salad dressings. Minimal trans fat intake is recommended because it increases cholesterol and contributes to heart disease.Healthwise. (2020, December 17). Types of fats. Michigan Medicine at University of Michigan. https://www.uofmhealth.org/health-library/aa160619 Micronutrients Micronutrients include vitamins and minerals. Vitamins Vitamins are necessary for many bodily functions, including growth, development, healing, vision, and reproduction. Most vitamins are considered essential because they are not manufactured by the body and must be ingested in the diet. Vitamin D is also manufactured through exposure to sunlight.Johnson, L. E. (2020, November). Overview of vitamins. Merck Manual Professional Version. https://www.merckmanuals.com/professional/nutritional-disorders/vitamin-deficiency,-dependency,-and-toxicity/overview-of-vitamins?redirectid=43#v2089966 Vitamin toxicity can be caused by overconsumption of certain vitamins, such as vitamins A, D, C, B6, and niacin. Conversely, vitamin deficiencies can be caused by various factors including poor food intake due to poverty, malabsorption problems with the gastrointestinal tract, drug and alcohol abuse, proton pump inhibitors, and prolonged parenteral nutrition. Deficiencies can take years to develop, so it is usually a long-term problem for patients.Johnson, L. E. (2020, November). Overview of vitamins. Merck Manual Professional Version. https://www.merckmanuals.com/professional/nutritional-disorders/vitamin-deficiency,-dependency,-and-toxicity/overview-of-vitamins?redirectid=43#v2089966 Vitamins are classified as water soluble or fat soluble. Water-soluble vitamins are not stored in the body and include vitamin C and B-complex vitamins: B1 (thiamine), B2 (riboflavin), B3 (niacin), B6 (pyridoxine), B12 (cyanocobalamin), and B9 (folic acid). Additional water-soluble vitamins include biotin and pantothenic acid. Excess amounts of these vitamins are excreted through the kidneys in urine, so toxicity is rarely an issue, though excess intake of vitamin B6, C, or niacin can result in toxicity.Healthwise. (2020, December 17). Vitamins: Their functions and sources. Michigan Medicine at University of Michigan. https://www.uofmhealth.org/health-library/ta3868 See Table 14.2a for a list of selected water-soluble vitamins, their sources, and their function.Healthwise. (2020, December 17). Vitamins: Their functions and sources. Michigan Medicine at University of Michigan. https://www.uofmhealth.org/health-library/ta3868,Healthwise. (2020, December 17). Vitamins: Their functions and sources. Michigan Medicine at University of Michigan. https://www.uofmhealth.org/health-library/ta3868,Johnson, L. E. (2020, November). Folate deficiency. Merck Manual Professional Version. https://www.merckmanuals.com/professional/nutritional-disorders/vitamin-deficiency-dependency-and-toxicity/folate-deficiency,Johnson, L. E. (2020, November). Niacin deficiency. Merck Manual Professional Version. https://www.merckmanuals.com/professional/nutritional-disorders/vitamin-deficiency-dependency-and-toxicity/niacin-deficiency,Johnson, L. E. (2020, November). Riboflavin deficiency. Merck Manual Professional Version. https://www.merckmanuals.com/professional/nutritional-disorders/vitamin-deficiency-dependency-and-toxicity/riboflavin-deficiency,Johnson, L. E. (2020, November). Thiamin deficiency. Merck Manual Professional Version. https://www.merckmanuals.com/professional/nutritional-disorders/vitamin-deficiency-dependency-and-toxicity/thiamin-deficiency,Johnson, L. E. (2020, November). Vitamin B6 deficiency and dependency. Merck Manual Professional Version. https://www.merckmanuals.com/professional/nutritional-disorders/vitamin-deficiency-dependency-and-toxicity/vitamin-b6-deficiency-and-dependency,Johnson, L. E. (2020, November). Vitamin B12 deficiency. Merck Manual Professional Version. https://www.merckmanuals.com/professional/nutritional-disorders/vitamin-deficiency-dependency-and-toxicity/vitamin-b12-deficiency,Johnson, L. E. (2020, November). Vitamin C deficiency. Merck Manual Professional Version. https://www.merckmanuals.com/professional/nutritional-disorders/vitamin-deficiency-dependency-and-toxicity/vitamin-c-deficiency Table 14.2a Selected Water-Soluble Vitamins \| Water-Soluble Vitamin \| Sources \| Functions \| Deficiency \| \|---\|---\|---\|---\| \| C (Ascorbic Acid) \| Citrus fruits, broccoli, greens, sweet peppers, tomatoes, lettuce, potatoes, tropical fruits, and strawberries \| Infection prevention, wound healing, collagen formation, iron absorption, amino acid metabolism, antioxidant, and bone growth in children. \| Early Signs: weakness, weight loss, myalgias, and irritability. Late Signs: scurvy; swollen, spongy gums; loose teeth; bleeding gums and skin; poor wound healing; edema; leg pain; anorexia; irritability; and poor growth in children. \| \| B1 (Thiamine) \| Nuts, liver, whole grains, pork, and legumes \| Nerve function; metabolism of carbohydrates, fat, amino acids, glucose, and alcohol; appetite and digestion. \| Fatigue, memory deficits, insomnia, chest pain, abdominal pain, anorexia, numbness of extremities, muscle wasting, heart failure, and shock in severe cases. \| \| B2 (Riboflavin) \| Eggs, liver, leafy greens, milk, and whole grains \| Protein and carbohydrate metabolism, healthy skin, and normal vision. \| Pallor, lip fissures, and seborrheic dermatitis. \| \| B3 (Niacin) \| Fish, chicken, eggs, dairy, mushrooms, peanut butter, whole grains, and red meat \| Glycogen metabolism, cell metabolism, tissue regeneration, fat synthesis, nerve function, digestion, and skin health. \| Pellagra characterized by skin lesions at pressure points/sun exposed skin, glossitis (swollen tongue), constipation progressing to bloody diarrhea, abdominal pain, abdominal distention, nausea, psychosis, and encephalopathy. \| \| B6 (Pyridoxine) \| Organ meats, fish, and various fruits and vegetables \| Protein metabolism and red blood cell formation. \| Rare due to presence in most foods. Peripheral neuropathy, seizures refractory to antiseizure medications, anemia, glossitis (swollen tongue), seborrheic dermatitis, depression, and confusion. \| \| B9 (Folic Acid) \| Liver, legumes, leafy greens, seeds, orange juice, and enriched refined grains \| Coenzyme in protein metabolism and cell growth, red blood cell formation, and prevention of fetal neural tube defects in utero. \| Glossitis (swollen tongue), confusion, depression, diarrhea, anemia, and fetal neural tube defects. \| \| B12 (Cyanocobalamin) \| Meat, organ meat, dairy, seafood, poultry, and eggs \| Mature red blood cell formation, DNA/RNA synthesis, new cell formation, and nerve function. \| Pernicious anemia from lack of intrinsic factor in intestines. Early Signs: weight loss, abdominal pain, peripheral neuropathy, weakness, hyporeflexia, and ataxia. Late Signs: irritability, depression, paranoia, and confusion. \| Fat-soluble vitamins are absorbed with fats in the diet and include vitamins A, D, E, and K. They are stored in fat tissue and can build up in the liver. They are not excreted easily by the kidneys due to storage in fatty tissue and the liver, so overconsumption can cause toxicity, especially with vitamins A and D.Healthwise. (2020, December 17). Vitamins: Their functions and sources. Michigan Medicine at University of Michigan. https://www.uofmhealth.org/health-library/ta3868 See Table 14.2b for a list of selected fat-soluble vitamins, their sources, their function, and manifestations of deficiencies and toxicities.Healthwise. (2020, December 17). Vitamins: Their functions and sources. Michigan Medicine at University of Michigan. https://www.uofmhealth.org/health-library/ta3868,Healthwise. (2020, December 17). Vitamins: Their functions and sources. Michigan Medicine at University of Michigan. https://www.uofmhealth.org/health-library/ta3868,Johnson, L. E. (2020, November). Vitamin A deficiency. Merck Manual Professional Version. https://www.merckmanuals.com/professional/nutritional-disorders/vitamin-deficiency-dependency-and-toxicity/vitamin-a-deficiency,Johnson, L. E. (2020, November). Vitamin D deficiency and dependency. Merck Manual Professional Version. https://www.merckmanuals.com/professional/nutritional-disorders/vitamin-deficiency-dependency-and-toxicity/vitamin-d-deficiency-and-dependency,Johnson, L. E. (2020, November). Vitamin D toxicity. Merck Manual Professional Version. https://www.merckmanuals.com/professional/nutritional-disorders/vitamin-deficiency-dependency-and-toxicity/vitamin-d-toxicity,Johnson, L. E. (2020, November). Vitamin E deficiency. Merck Manual Professional Version. https://www.merckmanuals.com/professional/nutritional-disorders/vitamin-deficiency-dependency-and-toxicity/vitamin-e-deficiency,Johnson, L. E. (2020, November). Vitamin E toxicity. Merck Manual Professional Version. https://www.merckmanuals.com/professional/nutritional-disorders/vitamin-deficiency-dependency-and-toxicity/vitamin-e-toxicity,Johnson, L. E. (2020, November). Vitamin K deficiency. Merck Manual Professional Version. https://www.merckmanuals.com/professional/nutritional-disorders/vitamin-deficiency-dependency-and-toxicity/vitamin-k-deficiency,Johnson, L. E. (2020, November). Vitamin K toxicity. Merck Manual Professional Version. https://www.merckmanuals.com/professional/nutritional-disorders/vitamin-deficiency-dependency-and-toxicity/vitamin-k-toxicity Table 14.2b Selected Fat-Soluble Vitamins \| Fat-Soluble Vitamin \| Source \| Function \| Deficiency \| Toxicity \| \|---\|---\|---\|---\|---\| \| A (Retinol) \| Retinol: fortified milk and dairy, egg yolks, and fish liver oil Beta carotene: green leafy vegetables, and dark orange fruits and vegetables \| Eyesight, epithelial, bone and tooth development, normal cellular proliferation, and immunity. \| Night blindness, rough scaly skin, dry eyes, and poor tooth/ bone development. Causes poor growth and infections common with mortality >50%. \| Dry, itchy skin; headache; nausea; blurred vision; and yellowing skin (carotenosis). \| \| D \| Milk, dairy, sun exposure, egg yolks, fatty fish, and liver \| Changed to active form with sun exposure. Needed for calcium/ phosphorus absorption, immunity, and bone strength. \| Rickets, poor dentition, tetany, osteomalacia, muscle aches and weakness, bone pain, poor calcium absorption leading to hypocalcemia and subsequent hyperparathyroidism and tetany. \| Hypercalcemia resulting in nausea, vomiting, anorexia, renal failure, weakness, pruritus, and polyuria. \| \| E \| Green leafy vegetables, whole grains, liver, egg yolks, nuts, and plant oils \| Anticoagulant, antioxidant, and cellular protection. \| Red blood cell breakdown leading to anemia, neuron degeneration, neuropathy, and retinopathy. \| Rare. Occasionally muscle weakness, fatigue, GI upset with diarrhea, and hemorrhagic stroke. \| \| K \| Green leafy vegetables and green vegetables produced by bacteria in intestines \| Needed for producing clotting factors in the liver. \| Rare in adults. Prolonged clotting times, hemorrhaging (especially in newborns causing morbidity & mortality), and jaundice. \| Rare, but can interfere with effectiveness of certain anticoagulant medications (Warfarin). \| Minerals Minerals are inorganic materials essential for hormone and enzyme production, as well as for bone, muscle, neurological, and cardiac function. Minerals are needed in varying amounts and are obtained from a well-rounded diet. In some cases of deficiencies, mineral supplements may be prescribed by a health care provider. Deficiencies can be caused by malnutrition, malabsorption, or certain medications, such as diuretics. Minerals are classified as either macrominerals or trace minerals. Macrominerals are needed in larger amounts and are typically measured in milligrams, grams, or milliequivalents. Macrominerals include sodium, potassium, calcium, magnesium, chloride, and phosphorus. Macrominerals are discussed in further detail in the “Electrolytes” section of the “Fluids and Electrolytes” chapter of this book. Trace minerals are needed in tiny amounts. Trace minerals include zinc, iron, chromium, copper, fluorine, iodine, manganese, molybdenum, and selenium.MedlinePlus [Internet]. Bethesda (MD): National Library of Medicine (US); [updated 2020, Oct 19]. Minerals; [reviewed 2015, Apr 2; cited 2021, Mar 5]. https://medlineplus.gov/minerals.html See Table 14.2c for a list of selected macrominerals and Table 14.2d for a list of trace minerals.Texas Heart Institute. (n.d.). Minerals: What they do, where to get them. https://www.texasheart.org/heart-health/heart-information-center/topics/minerals-what-they-do-where-to-get-them/,Texas Heart Institute. (n.d.) Trace elements: What they do and where they get them. https://www.texasheart.org/heart-health/heart-information-center/topics/trace-elements/,Texas Heart Institute. (n.d.). Minerals: What they do, where to get them. https://www.texasheart.org/heart-health/heart-information-center/topics/minerals-what-they-do-where-to-get-them/,Texas Heart Institute. (n.d.) Trace elements: What they do and where they get them. https://www.texasheart.org/heart-health/heart-information-center/topics/trace-elements/ Table 14.2c Macrominerals \| Macromineral \| Source \| Function \| \|---\|---\|---\| \| Sodium \| Table salt, spinach, and milk \| Water balance \| \| Potassium \| Legumes, potatoes, bananas, and whole grains \| Muscle contraction, cardiac muscle function, and nerve function \| \| Calcium \| Dairy, eggs, and green leafy vegetables \| Bone and teeth development, nerve function, muscle contraction, immunity, and blood clotting \| \| Magnesium \| Raw nuts, spinach (cooked has higher magnesium content), tomatoes, and beans \| Cell energy, muscle function, cardiac function, and glucose metabolism \| \| Chloride \| Table salt \| Fluid and electrolyte balance and digestion \| \| Phosphorus \| Red meat, poultry, rice, oats, dairy, and fish \| Bone strength and cellular function \| Table 14.2d Trace Minerals \| Trace Mineral \| Source \| Function \| \|---\|---\|---\| \| Zinc \| Eggs, spinach, yogurt, whole grains, fish, and brewer’s yeast \| Immune function, healing, and vision \| \| Iron \| Red meat, organ meats, spinach, shrimp, tuna, salmon, kidney beans, peas, and lentils (nonanimal forms are harder to absorb, so need more!) \| Hemoglobin production and collagen production \| \| Chromium \| Whole grains, meat, and brewer’s yeast \| Glucose metabolism \| \| Copper \| Shellfish, fruits, nuts, and organ meats \| Hemoglobin production, collagen, elastin, neurotransmitter production, and melanin production \| \| Flourine \| Fluoridated water and toothpaste \| Retention of calcium in bones and teeth \| \| Iodine \| Iodized salt and seafood \| Energy production and thyroid function \| \| Manganese \| Whole grain and nuts \| Not fully understood \| \| Molybdenum \| Organ meats, green leafy vegetables, legumes, whole grains, and dairy \| Not fully understood; detoxification \| \| Selenium \| Broccoli, cabbage, garlic, whole grains, brewer’s yeast, celery, onions, and organ meats \| Not fully understood \| Nutritional Guidelines Nutritional guidelines are developed by governmental agencies to provide guidance to the population on how to best meet nutritional needs. These guidelines may vary by country. The National Academies of Sciences, Engineering, and Medicine set the Dietary Reference Intakes (DRIs) for the United States and Canada. Dietary Reference Intakes (DRIs) are a set of reference values used to plan and assess nutrient intakes of healthy people, including proteins, carbohydrates, fats, vitamins, minerals, and fiber. Nutrients included in the DRIs are obtained through a typical diet, although some foods may be fortified with certain nutrients that are commonly deficient in diets.U.S. Department of Agriculture and U.S. Department of Health and Human Services. (2020). Dietary guidelines for Americans, 2020-2025 (9th ed.). https://www.dietaryguidelines.gov/ Choose MyPlate Food Guide The U.S. Department of Agriculture (USDA) issues dietary guidelines for appropriate serving sizes of each food group and number of servings recommended each day. The “Choose MyPlate” food guide is an easy-to-understand visual representation of how a healthy plate of food should be divided based on food groups. See Figure 14.4“MyPlate_blue.png” by USDA is licensed under CC0for a Choose MyPlate image. A little more than half of the plate should be grains and vegetables, with a focus on whole grains and a variety of vegetables. About one quarter of the plate should be fruits, with an emphasis on whole fruits. About one quarter of the plate should be protein, with an emphasis on consuming a variety of low-fat protein sources. All of these groups combined should make up no more than 85% of daily caloric intake based on a 2,000 calorie diet. Fats, oils, and added sugars are not included, but should make up no more than 15% of daily caloric intake. Foods should be selected that are as nutrient-dense as possible. Nutrient-dense means there is a high proportion of nutritional value relative to calories contained in the food, such as fruits and vegetables. Conversely, calorie-dense foods should be minimized because they have a large amount of calories with few nutrients. For example, candy and soda are calorie-dense with few nutrients and should be minimized.U.S. Department of Agriculture and U.S. Department of Health and Human Services. (2020). Dietary guidelines for Americans, 2020-2025 (9th ed.). https://www.dietaryguidelines.gov/,USDA MyPlate. (n.d.). What’s on your plate? U.S. Department of Agriculture. https://www.myplate.gov/ See the following hyperlink to the MyPlate web site for further information on USDA dietary guidelines and patient educational materials Read more about USDA dietary guidelines at https://www.myplate.gov/. “MyPlate_blue.png” by USDA is licensed under CC0 MyPlate information and images are also available in several other languages so that education can be tailored to the patient’s preferred language. For example, Figure 14.5“MyPlate_Vietnamese.png” by USDA is licensed under CC0 shows MyPlate in Vietnamese. This image would be accompanied with written information about food groups that include the patient’s typical dietary choices. Vegetable Group For a well-rounded diet, a variety of vegetables should be consumed, including vegetables from all five vegetable groups: dark green leafy vegetables; red and orange vegetables; beans, peas, and lentils (formerly called the legumes group); starchy vegetables; and other vegetables. Vegetables can be fresh, frozen, canned, or dried. Dark green leafy vegetables include kale, Swiss chard, spinach, broccoli, and salad greens. Red and orange vegetables include carrots, bell peppers, sweet potatoes, tomatoes, tomato juice, and squash. The beans, peas, and lentils group includes dried beans, black beans, chickpeas, kidney beans, split peas, and black-eyed peas. (Note that this group does not include green beans or green peas.) This vegetable group also supplies some protein and can be included in the protein group as well. Starchy vegetables include root vegetables, such as potatoes, as well as corn. The “other vegetables” category includes any vegetable that doesn’t fit in the other four categories, such as asparagus, avocados, brussels sprouts, cabbage, cucumbers, snow peas, and mushrooms, and a variety of others. Daily serving suggestions of vegetables for individuals with a 2,000 calorie diet are 2 ½ cup equivalents of vegetables per day. For example, a “one cup equivalent” equals 1 cup raw or cooked vegetables, one cup 100% vegetable juice, ½ cup of dried vegetables, or 2 cups of leafy green vegetables. Approximately 90% of Americans do not meet the recommended daily intake of vegetables.U.S. Department of Agriculture and U.S. Department of Health and Human Services. (2020). Dietary guidelines for Americans, 2020-2025 (9th ed.). https://www.dietaryguidelines.gov/ See Figure 14.6“Food-healthy-vegetables-potatoes_(23958160949).jpg” by www.Pixel.la Free Stock Photos is licensed under CC0 for an image of vegetables. Grain Group Grains are classified as whole grains or refined grains. Whole grains include the entire grain kernel and supply more fiber than refined grains. Examples of whole grains include amaranth, whole barley, popcorn, oats, whole grain cornmeal, brown or wild rice, and whole grain cereal or crackers. Refined grains have been processed to remove parts of the grain kernel and supply little fiber. As a result, they quickly increase blood glucose levels. Examples of refined grains include white bread, white rice, Cream of Wheat, pearled barley, white pasta, and refined-grain cereals or crackers. Some grains are fortified to ensure adequate intake of folic acid. See Figure 14.7 “front_en.3.400.jpg” by openfoodfacts-contributors is licensed under CC BY-SA 3.0 for an image of whole grain whole wheat bread. The daily serving suggestions of grains for an individual with a 2,000 calorie diet are six ounce equivalents per day, split equally between whole and refined grains. For example, a “one ounce equivalent” of grains equals ½ cup of cooked rice, pasta, or cereal or 1 cup of flaked cereal. Most Americans consume adequate amounts of total grains, although roughly 98% are deficient in recommended whole grain amounts, and 74% consume more than the recommended refined grain amounts.U.S. Department of Agriculture and U.S. Department of Health and Human Services. (2020). Dietary guidelines for Americans, 2020-2025 (9th ed.). https://www.dietaryguidelines.gov/ Fruit Group Fruits can be frozen, canned, or dried, in addition to 100% fruit juice. A few examples of fruits include apples, oranges, bananas, melons, peaches, apricots, pineapples, and rhubarb. Daily serving suggestions of fruits for an individual with a 2,000 calorie diet are 2 cup equivalents per day. For example, “one cup equivalent” equals 1 cup of raw or cooked fruit, 8 ounces of 100% fruit juice, or ½ cup of dried fruit. Approximately 80% of Americans do not consume the recommended daily intake of fruits.U.S. Department of Agriculture and U.S. Department of Health and Human Services. (2020). Dietary guidelines for Americans, 2020-2025 (9th ed.). https://www.dietaryguidelines.gov/ See Figure 14.8“Culinary_fruits_cropped_top_view.jpg” by Bill Ebbesen is licensed under CC BY 3.0 for an image of fruits. Dairy Group Dairy products can be liquid, dried, semi-solid, or solid depending on the type of product. Dairy products include milk, lactose-free milk, fortified soy milk, buttermilk, cheese, yogurt, and kefir. Sour cream and cream cheese are not considered dairy items in terms of nutritional benefits. Daily serving suggestions of dairy products for an individual with a 2,000 calorie diet are 3 cup equivalents per day. For example, “one cup equivalent” equals 1 cup of milk, soy milk, or yogurt; 1 ½ ounces of natural cheese, or 2 ounces of processed cheese. Approximately 90% of Americans consume less than the recommended daily intake of dairy products.U.S. Department of Agriculture and U.S. Department of Health and Human Services. (2020). Dietary guidelines for Americans, 2020-2025 (9th ed.). https://www.dietaryguidelines.gov/ See Figure 14.9“Good_Dairy_Sources.png” by Brookepinsent is licensed under CC BY-SA 4.0 for an image of dairy products. Protein Group Proteins are categorized by the type of protein source. The meats, poultry, and eggs category consists of any type of animal or poultry meat, organ meat, or poultry egg. Lean meats should be selected to minimize fat and calorie intake from high-fat meats. The seafood category includes any type of fish, clams, crab, lobster, oyster, and scallops. It is important to choose fish with low mercury levels to prevent negative effects of a buildup of mercury in the body. In general, large, fatty ocean fish, such as tuna, have higher levels of mercury due to their diet and storage of mercury in their fatty tissues. The nuts, seeds, and soy products category includes tree nuts, peanuts, nut butters, seeds, or seed butters. Soy products include tofu and any other products made from soy. Unsalted nuts should be selected to avoid excess salt intake. Protein is also contained in other food groups, such as dairy or the vegetable category of peas, beans, and lentils. Daily serving suggestions of proteins for individuals with a 2,000 calorie diet are 5 ½ ounce equivalents per day. Servings should total up to 26 ounce equivalents per week of meats, eggs, and poultry; 8 ounce equivalents per week of seafood; and 5 ounce equivalents per week of nuts, seeds, or soy products. A “one ounce equivalent” of protein equals 1 ounce of lean meat, one egg, ¼ cup cooked beans, or 1 tablespoon of peanut butter. Most Americans consume adequate amounts of protein, but many consume proteins high in saturated fat and sodium that contribute to diseases such as coronary artery disease.U.S. Department of Agriculture and U.S. Department of Health and Human Services. (2020). Dietary guidelines for Americans, 2020-2025 (9th ed.). https://www.dietaryguidelines.gov/ Oil/Fat Group Examples of oils are vegetable oil, canola oil, olive oil, butter, lard, and coconut oil. Daily serving suggestions of fats or oils for individuals with a 2,000 calorie diet are 27 grams per day. While it is important to limit oils and fats due to their calorie-dense nature, some fat and oil intake is essential for nutrient absorption and overall health. It is best to select healthy unsaturated fats, such as avocados, nuts, or olive oil.U.S. Department of Agriculture and U.S. Department of Health and Human Services. (2020). Dietary guidelines for Americans, 2020-2025 (9th ed.). https://www.dietaryguidelines.gov/ Gender A person’s gender affects their calorie and nutrient requirements. Males typically have higher calorie and protein needs related to increased muscle mass. Females typically require fewer calories to maintain their body weight due to a higher proportion of adipose (fat tissue) than muscle. Menstruating females also have higher iron requirements to offset losses that occur during menstruation. Read Nutrition and Food Safety Information and Resources for Healthcare Professionals from the U.S. Food and Drug Administration. View the infographic “What’s MyPlate All About?” from the USDA. Factors Affecting Nutritional Status Now that we have discussed basic nutritional concepts and dietary guidelines, let’s discuss factors that can affect a person’s nutritional status. Many things that can cause altered nutrition, such as physiological factors, cultural and religious beliefs, economic resources, drug and nutrient disorders, surgery, altered metabolic states, alcohol and drug abuse, and psychological states. Physiological Factors Nutritional intake is affected by several physiological factors. Appetite is controlled by the hypothalamus, a tiny gland deep within the brain that triggers feelings of hunger or fullness depending on hormone and neural signals being sent and received. See Figure 14.10“Hypothalamus.jpg” by Methoxyroxy~commonswiki is in the Public Domain for an image of the hypothalamus indicated by the red arrow. Hunger causes a feeling of emptiness in the abdomen and is often accompanied by audible noises coming from the abdomen as the stomach contracts due to emptiness. Hunger can cause feelings of discomfort, nausea, and tiredness. Satiety is a feeling of fullness that often comes after eating, although it can also be caused by impairments of the hypothalamus. Electrolyte imbalances and fluid volume imbalances can also trigger hunger and thirst by sending signals to the hypothalamus.Human Nutrition by University of Hawai’i at Mānoa Food Science and Human Nutrition Program is licensed under CC BY 4.0 The five senses play an important role in food intake. For example, food with a pleasing aroma may induce mouth watering and hunger, whereas food or environments with displeasing aromas often suppress the appetite. Texture and taste of foods also play a role in stimulation of appetite. Poor dentition or poor oral care has a negative effect on appetite, so adequate oral care is crucial for patients prior to eating.Human Nutrition by University of Hawai’i at Mānoa Food Science and Human Nutrition Program is licensed under CC BY 4.0 Additionally, the condition of a patient’s teeth and gums, the fit of dentures, and gastrointestinal function also play an important role in nutrition. Loose teeth, swollen gums, or poor-fitting dentures can make eating difficult. Difficulty swallowing, called dysphagia, can make it dangerous for the patient to swallow food because it can result in pneumonia from aspiration of food into the lungs. Special soft diets or enteral or parenteral nutrition are typically prescribed for patients with dysphagia. Nurses collaborate with speech therapists when assessing and managing dysphagia. A poorly functioning gastrointestinal tract makes nutrient absorption difficult and can result in malnourishment. Diseases that cause inflammation of the gastrointestinal tract impair absorption of nutrients. Examples of these conditions include esophagitis, gastritis, inflammatory bowel disease, and cholecystitis. Patients with these disorders should select nutrient-dense foods and may require prescribed supplements to increase nutrient intake. Cultural and Religious Beliefs Cultural and religious beliefs often influence food selection and food intake. It is important for nurses to conduct a thorough patient assessment, including food preferences, to ensure adequate nutritional intake during hospitalization. The nurse should not assume a particular diet based on a patient’s culture or religion, but instead should determine their individual preferences through the assessment interview. Cultural beliefs affect types of food eaten and when they are eaten. Some foods may be restricted due to beliefs or religious rituals, whereas other foods may be viewed as part of the healing process. For example, some cultures do not eat pork because it is considered unclean, and others eat “kosher” food that prescribes how food is prepared. Some religions fast during religious holidays from sunrise to sunset, where others avoid eating meat during the time of Lent.Dindyal, S., & Dindyal, S. (n.d.). How personal factors, including culture and ethnicity, affect the choices and selection of food we make. Internet Scientific Publications, 1(3). https://ispub.com/IJTWM/1/2/11779,Stewardship. (n.d.). What is Lent? When does Lent start? What to do during Lent? https://40acts.org.uk/about/what-is-lent/?__cf_chl_jschl_tk__=ef2ed5d0d141e0ea2b579938aca20e0e943f1c75-1614133089-0-AWdOUzF-oUz7XgHuq9pRLnxaEUF5qIJeJYQwB4UPNFLdq498NOv0E_PhRZ_-2Fnlf-j-ar1ifd4YLDpre2QBuuMl6Kl_tI7wGUp8CiI7_K28S-RBVgOp_30ChPVHXqS1_FCgntbnR8yj7TPb8Lsz1iTpbD5KCZVxOJeTw_f03LYD_DB7gZN0Tbsv-r4EQkXEP-Bvgf3rX_uyNNxXfEUvXiZ88b1uD4Dh3ltPLjc9ZxmBCkQS36pkRU7iIu4eRVTfbRON5zBGmxuiriWsRqM5l9aP_yNAkL-0SZhbMtAJOR34IHilovA68VFHPP6au-681TyrxjlJd1IlSzsH1nf7TfU Read more about the impact of religious and cultural beliefs on food intake in the “Spirituality” chapter of this book. Economic Resources If a patient has inadequate financial resources, food security and food choices are often greatly impacted. Healthy, nutrient-dense, fresh foods typically cost more than prepackaged, heavily processed foods. Poor economic status is correlated with the consumption of calorie-dense, nutrient-poor food choices, putting these individuals at risk for inadequate nutrition and obesity.Alkerwi, A., Vernier, C., Sauvageot, N., Crichton, G., & Elias, M. (2015). Demographic and socioeconomic disparity in nutrition: Application of a novel correlated component regression approach. BMJ Open, 5(5). https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4431064/ Social programs such as Meals on Wheels, free or reduced-cost school breakfast and lunch programs, and government subsidies based on income help reduce food insecurity and promote the consumption of healthy, nutrient-dense foods. Nurses refer at-risk patients to social workers and case managers for assistance in applying for these social programs. Drug and Nutrient Interactions Some prescription drugs affect nutrient absorption. For example, some medications such as proton pump inhibitors (omeprazole) alter the pH of stomach acid, resulting in poor absorption of nutrients. Other medications, such as opioids, often decrease a person’s appetite or cause nausea, resulting in decreased calorie and nutrient intake. Surgery Surgery can affect a patient’s nutritional status due to several factors. Food and drink are typically withheld for a period of time prior to surgery to prevent aspiration of fluid into the lungs during anesthesia. Anesthesia and pain medication used during surgery slow peristalsis, and it often takes time to return to normal. Slow peristalsis can cause nausea, vomiting, and constipation. Until the patient is able to pass gas and bowel sounds return, the patient is typically ordered to have nothing by mouth (NPO). If a patient experiences prolonged NPO status, such as after significant abdominal surgery, intravenous fluids and nutrition may be required. Surgery also stimulates the physiological stress response and increases metabolic demands, causing the need for increased calories. The stress response can also cause elevated blood glucose levels due to the release of corticosteroids, even if the patient has not been previously diagnosed with diabetes mellitus. For this reason, nurses often monitor post-op patients’ bedside blood glucose levels carefully. Bowel resection surgery in particular has a negative impact on nutrient absorption. Because all or parts of the intestine are removed, there is decreased absorption of nutrients, which can result in nutrient deficiencies. Many patients who have experienced bowel resection require nutrient supplementation. Bariatric surgery is used to treat obesity and reduce obesity-related cardiovascular risk factors. Bariatric procedures alter the anatomy and physiology of the gastrointestinal tract, which makes patients susceptible to nutritional deficiencies.Lupoli, R., Lembo, E., et al. (2017) Bariatric surgery and long-term nutritional issues. World Journal of Diabetes, 8(11), 464-474. DOI: 10.4239/wjd.v8.i11.464 Read more about bariatric surgery and long-term nutritional issues using the hyperlink in the following box. Read more about bariatric surgery and long-term nutritional issues.Lupoli, R., Lembo, E., et al. (2017) Bariatric surgery and long-term nutritional issues. World Journal of Diabetes, 8(11), 464-474. DOI: 10.4239/wjd.v8.i11.464 Altered Metabolic States Metabolic demands impact nutrient intake. In conditions where metabolic demands are increased, such as during growth spurts in childhood or adolescence, nutritional intake should be increased. Disease states, such as cancer, hyperthyroidism, and AIDS, can increase metabolism and require an increased amount of nutrients. However, cancer treatment, such as radiation and chemotherapy, often causes nausea, vomiting, and decreased appetite, making it difficult for patients to obtain adequate nutrients at a time when they are needed in high amounts due to increased metabolic demand. Other diseases like diabetes mellitus cause complications with nutrient absorption due to insulin. Insulin is necessary for the metabolism of fats, proteins, and carbohydrates, but in patients with diabetes mellitus, insulin production is insufficient or their body is not able to effectively use circulating insulin. This lack of insulin can result in impaired nutrient metabolism. Alcohol and Drug Abuse Alcohol and drug abuse can affect nutritional status. Alcohol is calorie-dense and nutrient-poor. With alcohol use, the consumption of water, food, and other nutrients often decreases as patients “drink their calories.” This may result in decreased protein intake and body protein deficiency. Nutrient digestion and absorption can also decrease with alcohol consumption if the stomach lining becomes eroded or scarred. This can cause hemoglobin, hematocrit, albumin, folate, thiamine, vitamin B12, and vitamin C deficiencies, as well as decreased calcium, magnesium, and phosphorus levels.Gramlich, L., Tandon, P., & Rahman, A. (2019). Nutritional status in patients with sustained heavy alcohol use. UpToDate. Retrieved February 21, 2021, from https://www.uptodate.com/contents/nutritional-status-in-patients-with-sustained-heavy-alcohol-use?csi=5c4a69dc-6adc-4ae0-a572-4be3ef0e325f&source=contentShare Drug abuse of stimulants, such as methamphetamine and cocaine abuse, causes an increased metabolic rate and decreased appetite and contributes to weight loss and malnourishment. Psychological State Various psychological states have a direct effect on appetite and a patient’s desire to eat. Acute and chronic stress stimulates the hypothalamus and increases production of glucocorticoids and glucose. This can increase the person’s appetite, causing increased calorie intake, fat storage, and subsequent weight gain. When a person feels stressed, their food choices are often nutrient-poor and calorie-dense, which further increases weight gain and nutrient deficiencies. In other individuals, the stress response causes loss of appetite, weight loss, and nutrient deficiencies.Ulrich-Lai, Y. M., Fulton, S., Wilson, M., Petrovich, G., & Rinaman, L. (2015). Stress exposure, food intake and emotional state. Stress (Amsterdam, Netherlands), 18(4), 381–399. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4843770/ Depression can cause loss of appetite or overeating. Additionally, many antidepressants can cause weight gain as a side effect. 14.3 Applying the Nursing Process Open Resources for Nursing (Open RN) Now that we have discussed basic nutritional concepts, dietary guidelines, and factors affecting nutritional status, let’s apply the nursing process to this information when caring for patients. Assessment A thorough nutritional assessment provides information about an individual’s nutritional status, as well as risk factors for nutritional imbalances. Assessment starts with reviewing the patient’s medical record and initiating a patient interview, followed by a physical exam and review of lab and diagnostic test results. Subjective Assessment Subjective assessments include questions regarding normal eating patterns and risk factor identification. Subjective assessment data is obtained by interviewing the patient as a primary source or a family member or caregiver as a secondary source. While a wealth of subjective information can be obtained through a chart review, it is important to verify this information with either the patient or family member because details may be recorded inaccurately or may have changed over time. Subjective information to obtain when completing a nutritional assessment includes age, sex, history of illness or chronic disease, surgeries, dietary intake including a 24-hour diet recall or food diary, food preferences, cultural practices related to diet, normal snack and meal timings, food allergies, special diets, and food shopping or preparation activities. A detailed nutritional assessment can also provide important clues for identification of risk factors for nutritional deficits or excesses. For example, a history of anorexia or bulimia will put the patient at risk for vitamin, mineral, and electrolyte disturbances, as well as potential body image disturbances. Swallowing impairments place the patient at risk for decreased intake that may be insufficient to meet metabolic demands. Use of recreational drugs or alcohol places the patient at risk for insufficient nutrient intake and impaired nutrient absorption. Use of nutritional supplements places the patient at risk for excess nutrient absorption and potential toxicity. Recognizing and identifying risks to nutritional status help the nurse anticipate problems that may arise and identify complications as they occur. Ideally, the nurse will recognize subtle cues of impending or actual dysfunction and prevent bigger problems from happening. Objective Assessment Objective assessment data is information derived from direct observation by the nurse and is obtained through inspection, auscultation, and palpation. The nurse should consider nutritional status while performing a physical examination. The nurse begins the physical examination by making general observations about the patient’s status. A well-nourished patient has normal skin color and hair texture for their ethnicity, healthy nails, a BMI within normal range according to their height, and appears energetic. Height and weight should be accurately measured and documented. Height and weight in infants and children are plotted on a growth chart to give a percentile ranking across the United States. The infant or child should show a trend of consistent height and weight increase. Height and weight in adults are often compared to a Body Mass Index (BMI) graph. BMI can also be calculated using the following formulas: - BMI = weight (kilograms)/height(meters)2 - BMI = weight (pounds) x 703)/height(inches)2 To calculate BMI using a BMI table, the patient’s height is plotted on the horizontal axis and their weight is plotted on the perpendicular axis. The BMI is measured where the lines intersect. See Figure 14.11“Bmi-chart_colored.gif” by Cbizzy2313 is licensed under CC BY-SA 4.0 for an image of a BMI table. BMI is interpreted using the following ranges: - Less than 18.5: Underweight - 18.5-24.9: Desirable range - 25-29.9: Overweight - Equal or greater than 30: ObeseHood, W. A. (2020, September 25). Nutritional status assessment in adults technique. Medscape. https://emedicine.medscape.com/article/2141861-technique After completing the subjective and objective assessment, the data should be analyzed for expected and unexpected findings. See Table 14.3a for a comparison of expected versus unexpected assessment findings related to nutritional status on assessment, including those that require notification of the health care provider in bold font. Table 14.3a Expected Versus Unexpected Findings During Nutritional AssessmentHood, W. A. (2020, September 25). Nutritional status assessment in adults technique. Medscape. https://emedicine.medscape.com/article/2141861-technique \| Assessment \| Expected Findings \| Unexpected Findings Bolded items are critical conditions that require immediate health care provider notification. \| \|---\|---\|---\| \| General appearance \| Energetic; normal skin, hair, and nails; and normal weight related to height \| Lethargic, skin ulcerations, rashes, bruising, thinning or loss of hair, spooning of nails, obese, or underweight \| \| Eyes \| Normal vision and normal eye moisture \| Impaired night vision or dry eyes \| \| Mouth \| Moist mucous membranes, intact oral mucosa, and intact smooth tongue \| Dry/sticky mucous membranes, oral ulcerations, glossitis (swollen tongue), coughing while swallowing or inability to swallow, or swollen throat \| \| Extremities/Integumentary \| Normal skin, nontenting (good skin turgor) and supple texture \| Tenting (poor skin turgor), dry skin, edema, or shiny skin \| \| Neurological \| Normal sensation and normal cognition \| Numbness or tingling, tetany, dementia, or acute confusion \| \| Cardiac \| Normal heart tones, capillary refill < 3 seconds, normal pulses, and normal EKG tracing \| Bounding pulses, S3 heart tone, jugular venous distention, abnormal EKG tracing, or cardiac arrhythmias \| \| Respiratory \| Clear lung sounds throughout, normal respiratory rate, and no shortness of breath \| Crackles in lung fields, pink frothy sputum, shortness of breath, or respiratory distress \| \| Gastrointestinal \| Normal stool quality and frequency for patient, bowel sounds present x 4 quadrants, and absence of nausea/vomiting \| Constipation, diarrhea, nausea, or vomiting \| \| Urinary \| Clear urine, normal urine specific gravity, and urine output >30 mL/hr \| Decreased urine output <30 mL/hr or <0.5 mL/kg/hr, concentrated urine, or burning with urination \| \| Weight \| Normal BMI of 18.5-24.9, weight loss or gain of 0.5 to 1 pound per week is realistic, and <5% weight loss over 6 months \| BMI <18.5 or >25, weight gain or loss of > 1kg over 24 hrs, or severe weight loss of >10% over 6 months \| Review how to perform a physical examination on the body systems listed in Table 14.3a in Open RN Nursing Skills. Diagnostic and Lab Work Diagnostic and lab work results can provide important clues about a patient’s overall nutritional status and should be used in conjunction with a thorough subjective and objective assessment to provide an accurate picture of the patient’s overall health status. Common lab tests include hemoglobin (hgb), hematocrit (HCT), white blood cells (WBC), albumin, prealbumin, and transferrin. Anemia is a medical condition diagnosed by low hemoglobin levels. Hemoglobin is important for oxygen transport throughout the body. Anemia can be caused acutely by hemorrhage, but it is often the result of chronic iron deficiency, vitamin B12 deficiency, or folate deficiency. Iron supplements, B12 injections, folate supplements, and increased iron or folate intake in the diet can help increase hemoglobin levels. Albumin and prealbumin are proteins in the bloodstream. They maintain oncotic pressure so that fluid does not leak out of blood vessels into the extravascular space. (Read more about oncotic pressure in the “Fluids and Electrolytes” chapter.) Albumin and prealbumin levels are used as markers of malnutrition, but these levels can also be affected by medical conditions such as liver failure, kidney failure, inflammation, and zinc deficiency. Low albumin levels can indicate prolonged protein deficiency intake over several weeks, whereas prealbumin levels reflect protein intake over the previous few weeks. For this reason, prealbumin is often used to monitor the effectiveness of parenteral nutrition therapy.MedlinePlus [Internet]. Bethesda (MD): National Library of Medicine (US); [updated 2020, Nov 30]. Prealbumin blood test; [reviewed 2020, Nov 30; cited 2021, Mar 5]. https://medlineplus.gov/lab-tests/prealbumin-blood-test/,Simons, S. R., & Abdallah, L. M. (2012). Bedside assessment of enteral tube placement: Aligning practice with evidence. American Journal of Nursing, 112(2), 40-46. https://doi.org/10.1097/01.naj.0000411178.07179.68 Transferrin is a protein required for iron transport on red blood cells. Transferrin levels increase during iron deficiency anemia and decrease with renal or liver failure and infection. A patient’s amount of muscle wasting due to malnutrition is measured by a 24-hour urine creatinine level.Hood, W. A. (2020, September 25). Nutritional status assessment in adults laboratory medicine. Medscape. https://emedicine.medscape.com/article/2141861-labs If insufficient calories are consumed, the body begins to break down its own tissues in a process called catabolism. Blood urea nitrogen and creatinine are released as a by-product. A 24-hour urine collection measures these by-product levels to assess the degree of catabolism occurring. White blood cells will decrease with malnourishment, specifically with protein and vitamins C, D, and E and B-complex deficiencies. Low white blood cell counts place the patient at risk for infection because adequate white blood cells are necessary for a fully functioning immune system. See Table 14.3b for a description of selected lab values associated with nutritional status. As always, refer to agency lab reference ranges when providing patient care. Table 14.3b Selected Lab Values Associated with Nutritional StatusHood, W. A. (2020, September 25). Nutritional status assessment in adults laboratory medicine. Medscape. https://emedicine.medscape.com/article/2141861-labs,Ignativicius, D. D., Workman, M. L., & Rebar, C. (2018). Medical surgical nursing: Concepts for interprofessional collaborative care (9th ed.). Elsevier.,University of Rochester Medical Center. (n.d.). Health Encyclopedia. https://www.urmc.rochester.edu/encyclopedia.aspx \| Lab \| Normal Range \| Nursing Considerations Bolded items are critical conditions and require immediate health care provider notification. \| \|---\|---\|---\| \| Hemoglobin (Hgb) \| Females: 12 – 16 g/dL Males: \| Hemoglobin measures the oxygen-carrying capacity of blood. Decreased levels occur due to hemorrhage or deficiencies in iron, folate, or B12. 10 – 14: mild anemia 6 – 10: moderate anemia < 6: severe anemia \| \| Hematocrit (Hct) \| 37 – 50% \| Hematocrit is normally three times the patient’s hemoglobin level during normal fluid status. Increased levels occur with dehydration, and decreased levels occur with fluid overload or hemorrhage. \| \| White blood cells (WBC) \| 5,000 – 10,000 mm3 \| Increased levels occur due to infection. Decreased levels occur due to prolonged stress, poor nutrition, and vitamins C, D, and E and B-complex deficiencies. <4000: at risk for infection or sepsis >11,000: infection present \| \| Magnesium \| 1.6 – 2.6 mEq/L \| Decreased level with poor nutrition or alcohol abuse. Increased levels due to kidney dysfunction. Critical values can cause cardiac complications: <1.2 mg/dL or >4.9 mg/dL \| \| Albumin \| 3.4 – 5.4 g/dL \| Increased with dehydration. Decreased level due to zinc deficiency, corticosteroid use, protein deficiency over several weeks, or conditions resulting in muscle wasting/muscle loss. \| \| Prealbumin \| 15 – 36 mg/dL \| Increased levels with corticosteroid or contraceptive use. Decreased levels due to inflammation, poor immunity, protein depletion over a few weeks. \| \| Transferrin \| 250 – 450 mcg/dL \| Increased levels due to dehydration and iron deficiency. Decreased levels due to anemia; vitamin B12, folate, and zinc deficiency; protein depletion; and conditions resulting in muscle wasting/muscle loss. \| \| 24-hour urine creatinine \| Males: 0.8 – 1.8 g/24 hrs Females: 0.6 – 1.6 g/24 hrs \| Increased levels with renal disease and muscle breakdown. Decreased levels with progressive malnutrition as muscles atrophy. \| Various diagnostic tests may be ordered by the health care provider based on the patient’s medical conditions and circumstances. For example, a swallow study is a diagnostic test used for patients having difficulty swallowing. An abdominal X-ray is used to determine the correct placement of a feeding tube or to note any excess air or stool in the colon. A barium swallow is used in conjunction with a CT scan to note any blockages in the intestines. Life Span and Cultural Considerations Newborns and Infants A crucial amount of growth and development happens between birth to age two. For proper growth, development, and brain function, this age group requires nutrient-dense food choices, primarily because they eat so little compared to adults, but also because of their rapid growth rate that is higher than any other time of development. Ideally, newborns through age 6 months should be fed exclusively human breast milk if possible to develop immunity. Vitamin D and iron supplementation may be needed.U.S. Department of Agriculture and U.S. Department of Health and Human Services. (2020). Dietary guidelines for Americans, 2020-2025 (9th ed.). https://www.dietaryguidelines.gov/ For the first two to three days after birth, human milk contains colostrum, a thick yellowish-white fluid rich in proteins and immunoglobulin A (IgA). Colostrum helps protect the newborn from infection and builds normal intestinal bacteria. As breast milk matures after two to three days postpartum, it becomes lower in proteins and IgA and higher in carbohydrates and fat.This work is a derivative of StatPearls by Bryant & Thistle and is licensed under CC BY 4.0 Human donor milk may be used in some situations when the mother cannot breastfeed. If human donor milk is given, it should be sourced through an accredited human milk bank and pasteurized to minimize risk of spreading infectious diseases. There are many reasons infants may not be breastfed, including insufficient breast milk production, a personal choice not to breastfeed, or adoption of the newborn. If breastfeeding or donor milk is not an option, an iron-fortified commercial infant formula should be used exclusively through at least 6 months of age. Homemade or non-FDA approved infant formulas or toddler formulas should not be used because they may not meet the high nutritional needs of infants. Infants fed 100% commercial infant formula will not need vitamin D supplementation.U.S. Department of Agriculture and U.S. Department of Health and Human Services. (2020). Dietary guidelines for Americans, 2020-2025 (9th ed.). https://www.dietaryguidelines.gov/ After about six months of age, infants should begin to be introduced to additional nutrient-dense complementary foods that are developmentally appropriate. Foods should be introduced one at a time to monitor for food sensitivities. Introducing food at this time is to provide a varied diet, additional nutrients, and an introduction to different flavors and textures of food. Research shows that introduction to certain allergy-risk foods, such as peanut butter prior to one year of age, helps decrease the risk of developing a peanut allergy later in life. It is important to strictly avoid honey and other unpasteurized food and drink before one year of age to prevent botulism and other bacteria. Additionally, cow’s milk, fortified soy drinks, and fruit or vegetable juices should not be introduced before 1 year of age.U.S. Department of Agriculture and U.S. Department of Health and Human Services. (2020). Dietary guidelines for Americans, 2020-2025 (9th ed.). https://www.dietaryguidelines.gov/ Children and Adolescents Growth rate continues to be rapid from ages one through five, requiring adequate nutrition to meet these growth and metabolic demands. Caloric and nutritional intake requirements increase proportionately with age, but unfortunately, the quality of diet tends to decrease proportionately with age. This is in part due to younger children being dependent on adults for nutritional choices and intake while older children and adolescents begin to make their own food choices as they enter school. Poverty can also negatively impact nutritional intake in children and adolescents. School lunch and breakfast programs help mitigate the effects of poverty on nutrition by providing free to low-cost, nutritionally-balanced meals.U.S. Department of Agriculture and U.S. Department of Health and Human Services. (2020). Dietary guidelines for Americans, 2020-2025 (9th ed.). https://www.dietaryguidelines.gov/ Healthy dietary habits formed in childhood through adolescence help prevent obesity, cardiovascular disease, diabetes mellitus, and other chronic diseases later in life. It is important to provide children with a variety of different foods prepared in different ways to increase the likelihood of children accepting and growing accustomed to different foods. It is common for children to become picky in their food choices or decide to only eat one or a few different food items over a period of time. Allowing children to help select and prepare food can increase their acceptance of different food choices.U.S. Department of Agriculture and U.S. Department of Health and Human Services. (2020). Dietary guidelines for Americans, 2020-2025 (9th ed.). https://www.dietaryguidelines.gov/ Adults The adult life stage is ages 19 through 59. A major limiting factor to healthy nutrition in adults is development of poor nutritional habits early in life. These unhealthy diet habits can be very difficult to change due to food preferences, as well as lack of knowledge about proper nutrition. Metabolic rate and caloric needs decrease with increasing age. Females tend to require less caloric intake than males, though caloric and nutritional needs increase with pregnancy and breastfeeding. Without appropriate dietary intake or activity, weight gain will occur that can lead to obesity and other chronic diseases. Over 50% of Americans have one or more chronic diseases that are associated with poor diet and physical inactivity. Education regarding a healthy diet, including appropriate calorie, saturated fat, sugar, and sodium intakes, helps improve health in adults. Roughly 73% of males and 70% of females in America exceed the recommended daily intake of saturated fat, and up to 97% of males and 82% of females exceed the recommended daily intake of sodium. Approximately 97% of males and 90% of women in America do not consume the recommended intake of dietary fiber, including underconsumption of fruits, vegetables, and whole grains, which contributes to diet-related chronic diseases. Alcohol consumption can be problematic for maintaining a healthy diet. Chronic alcohol abuse can interfere with vitamin and mineral absorption and result in general malnourishment. Alcohol should be limited to one drink per day or less for women and two drinks or less per day for men. Alcohol should be avoided by those who are pregnant, breastfeeding, younger than 21 years old, have a chemical dependency, or have other underlying health conditions such as diabetes mellitus.U.S. Department of Agriculture and U.S. Department of Health and Human Services. (2020). Dietary guidelines for Americans, 2020-2025 (9th ed.). https://www.dietaryguidelines.gov/ Pregnancy and Lactation A well-balanced, healthy diet is essential during pregnancy and lactation to prevent maternal, fetal, and newborn problems. Nutritional requirements, such as calories, vitamins, and minerals, increase during pregnancy and lactation. Increased caloric needs should be met with nutrient-dense foods rather than calorie-dense foods that are higher in fats and sugars. Prenatal vitamins and mineral supplements are often prescribed during pregnancy and lactation, in addition to a nutrient-rich diet, to help ensure women meet requirements for folic acid, iron, iodine, choline, and vitamin D. Folic acid is necessary to prevent neural tube defects in the fetus during the first trimester of pregnancy. Iron requirements increase during pregnancy to support fetal development and prevent anemia. Iodine requirements increase during pregnancy and lactation for fetal neurocognitive development. Choline requirements also increase due to the need to replace maternal stores, as well as for fetal brain and spinal cord development.U.S. Department of Agriculture and U.S. Department of Health and Human Services. (2020). Dietary guidelines for Americans, 2020-2025 (9th ed.). https://www.dietaryguidelines.gov/ Older Adults People aged 65 years and older are considered older adults. Older adults are more likely to suffer from chronic illness and disease. Older adults have lower calorie needs than younger people, though they still need a diet full of nutrient-dense foods because their nutrient needs increase. Caloric needs decrease due to decreased activity, decreased metabolic rates, and decreased muscle mass. Chronic disease and medication can contribute to decreased nutrient absorption. Protein and vitamin B12 are commonly under consumed in older adults. Protein is necessary to prevent loss of muscle mass. Vitamin B12 deficiency can be a problem for older adults because absorption of vitamin B12 decreases with age and with certain medications. Adequate hydration is also a concern for older adults because feelings of thirst decrease with age, leading to poor fluid intake. Additionally, older adults may be concerned with bladder dysfunction so they may consciously choose to limit fluid intake. Loneliness, ability to chew and swallow, and poverty can also decrease dietary intake in older adults.U.S. Department of Agriculture and U.S. Department of Health and Human Services. (2020). Dietary guidelines for Americans, 2020-2025 (9th ed.). https://www.dietaryguidelines.gov/ Meals on Wheels, local senior centers, and other community programs can provide socialization and well-balanced meals to older adults. The Mini-Nutritional Assessment Short-Form is a screening tool used to identify older adults who are malnourished or at risk of malnutrition. Use the hyperlink in the following box to download this tool. Download the Mini-Nutritional Assessment Short-Form from The Hartford Institute for Geriatric Nursing.The Hartford Institute for Geriatric Nursing, New York University, Rory Meyers School of Nursing. (n.d.). Assessment tools for best practices of care for older adults. https://hign.org/consultgeri-resources/try-this-series Diagnosis After the assessment stage is conducted, data is analyzed, and pertinent information is clustered together, nursing diagnoses are selected based on defining characteristics. When creating a care plan for a patient, review a current nursing care planning source for current NANDA-I approved nursing diagnoses and interventions related to nutritional imbalances. NANDA-I nursing diagnoses related to nutrition include Imbalanced Nutrition: Less than Body Requirements, Overweight, Obesity, Risk for Overweight, Readiness for Enhanced Nutrition, and Impaired Swallowing.Herdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York, pp. 157, 158, 169-174. See Table 14.3c for additional information related to the diagnosis Imbalanced Nutrition: Less than Body Requirements.Herdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York, pp. 157, 158, 169-174. Table 14.3c Sample NANDA-I Nursing Diagnosis Related to NutritionHerdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York, pp. 157, 158, 169-174. \| NANDA-I Diagnosis \| Definition \| Sample Defining Characteristics \| \|---\|---\|---\| \| Imbalanced Nutrition: Less than Body Requirements \| Intake of nutrients insufficient to meet metabolic needs. \| Abdominal cramping Abdominal pain Alteration in taste sensation Body weight 20% or more below ideal weight range Diarrhea Food intake less than recommended daily allowance (RDA) Hyperactive bowel sounds Pale mucous membranes Satiety immediate upon ingesting food Sore buccal cavity Weakness of muscles required for chewing and swallowing \| A sample nursing diagnosis written in PES format is, “Imbalanced Nutrition: Less than Body Requirements related to insufficient dietary intake as evidenced by body weight 20% below ideal weight range and food intake less than recommended daily allowance.” Outcome Identification Goals for patients experiencing altered nutritional status depend on the selected nursing diagnosis and specific patient situation. Typically, goals relate to resolution of the nutritional imbalance and are broad in nature. An overall goal related to nutritional imbalances is, “The patient will weigh within normal range for their height and age.”Ackley, B., Ladwig, G., Makic, M.B., Martinez-Kratz, M., & Zanotti, M. (2020). Nursing diagnosis handbook: An evidence-based guide to planning care (12th ed.). Elsevier, pp. 651-657. Outcome criteria are specific, measurable, achievable, realistic, and time-oriented. A sample SMART goal is, “The patient will select three dietary modifications to meet their long-term health goals using USDA MyPlate guidelines by discharge.”Ackley, B., Ladwig, G., Makic, M.B., Martinez-Kratz, M., & Zanotti, M. (2020). Nursing diagnosis handbook: An evidence-based guide to planning care (12th ed.). Elsevier, pp. 651-657. Planning Interventions After SMART outcome criteria are customized to the patient’s situation, nursing interventions are selected to help them achieve their identified outcomes. Interventions are specific to the alteration in nutritional status and should accomodate the patient’s cultural and religious beliefs. The box below outlines selected interventions related to nutrition therapy. Nutrition TherapyButcher, H., Bulechek, G., Dochterman, J., & Wagner, C. (2018). Nursing Interventions Classification (NIC). Elsevier, p. 272. - Monitor food/fluid ingested and calculate daily caloric intake, as appropriate - Monitor appropriateness of diet orders to meet daily nutritional needs, as appropriate - Determine in collaboration with the dietician, the number of calories and types of nutrients needed to meet nutritional requirements, as appropriate - Determine food preferences with consideration of the patient’s cultural and religious preferences - Encourage nutritional supplements, as appropriate - Provide patients with nutritional deficits high-protein, high-calorie, nutritious finger foods and drinks that can be readily consumed, as appropriate - Determine need for enteral tube feedings in collaboration with a dietician - Administer enteral feedings, as prescribed - Administer parenteral nutrition, as prescribed - Structure the environment to create a pleasant and relaxing meal atmosphere - Present food in an attractive, pleasing manner, giving consideration to color, texture, and variety - Provide oral care before meals - Assist the patient to a sitting position before eating or feeding - Implement interventions to prevent aspiration in patients receiving enteral nutrition - Monitor laboratory values, as appropriate - Instruct the patient and family about prescribed diets - Refer for diet teaching and planning, as appropriate - Give the patient and family written examples of prescribed diet Patients may be prescribed special diets due to medical conditions or altered nutrition states. See Table 14.3d for commonly prescribed special diets. Table 14.3d Commonly Prescribed Special Diets \| Diet \| Description \| Example \| Indication \| \|---\|---\|---\|---\| \| NPO \| Nothing by mouth–no food or drink allowed Note: Oral care is very important during NPO status. \| Before and after surgery or procedures, when peristalsis is absent, or during severe nausea or vomiting episodes, or for changes in mental status \| \| \| Clear liquids \| Fluids or solids that are liquid at room temperature, without residue, clear, or see-through \| Water, apple juice, clear soda, Jello, popsicles, and broth \| After surgery when peristalsis is slow and diet is being advanced from NPO status \| \| Full liquids \| Fluids with residue \| Creamed soups, pudding, milk, orange juice, and creamed cereals \| Next step after clear liquids as diet is being advanced \| \| Mechanical soft \| Chopped, ground, pureed foods that break apart easily without a knife \| Soft cheeses, cottage cheese, ground meat, broiled or baked fish, cooked vegetables, and fruit \| Poor or absent dentition; dysphagia \| \| Pureed \| Spoon thick with consistency of baby food \| Applesauce, pudding, mashed potatoes, pureed meats, vegetables, and fruit \| Dysphagia \| \| Restrictive \| Depends on the disease process \| Diabetic: controlled amount of carbohydrates Cardiac: low fat and no added salt Renal: low-sodium and low-potassium containing foods \| Diabetes mellitus Heart disease Renal failure or dialysis \| “Thickened liquids” are typically prescribed for patients with difficulty swallowing (dysphagia). Three consistencies of thickened liquids are: - Nectar-thick liquids: Easily pourable liquid comparable to apricot nectar or thick cream soups. - Honey-thick liquids: Slightly thicker liquid that is less pourable and drizzles from a cup or bowl. - Pudding-thick liquids: Liquids that hold their own shape. They are not pourable and usually require a spoon to eat. Nurses often thicken liquids in the patient’s room using a commercial thickener. Most commercial thickeners include directions for achieving the consistency prescribed. Enteral Nutrition Enteral nutrition is administered directly to a patient’s gastrointestinal tract while bypassing chewing and swallowing. Enteral feedings are prescribed for patients when chewing and/or swallowing are impaired or when there is poor nutritional intake and/or malnutrition. Examples of enteral tube access are nasogastric tubes (NG), orogastric tubes (OG), percutaneous endoscopic gastrostomy (PEG) tubes, or percutaneous endoscopic jejunostomy (PEJ) tubes. See Figure 14.12“Types and Placement of Enteral Tubes” by Meredith Pomietlo for Chippewa Valley Technical College is licensed under CC BY 4.0 for an illustration of common enteral tube placement. Nasogastric tubes enter the nare and travel through the esophagus and into the stomach. Liquid tube feedings are infused through this tube and directly into the stomach. Orogastric tubes work in the same manner except they are inserted through the mouth into the esophagus and then into the stomach. Orogastric tubes are typically used with mechanically intubated and sedated patients and should never be used in conscious patients because they can induce a gag reflex and cause vomiting. PEG tubes are inserted through the abdominal wall directly into the stomach, bypassing the esophagus. PEG tubes are used when there is an obstruction to the esophagus, the esophagus has been removed, or if long-term enteral feedings are expected. PEJ tubes are inserted through the abdominal wall directly into the jejunum, bypassing the esophagus and stomach. PEJ tubes are used when all or part of the stomach has been removed or if the provider determines PEJ placement would best suit the patient’s needs. There are several safety considerations for nurses to implement when enteral nutrition is being administered to prevent aspiration and dehydration. Tube placement must be verified after insertion, as well as before every medication or feeding is administered, to prevent inadvertent administration into the lungs if the tube has migrated out of position. Follow agency policy regarding checking placement. The American Association of Critical‐Care Nursing recommends that the position of a feeding tube should be checked and documented every four hours and prior to the administration of enteral feedings and medications by measuring the visible tube length and comparing it to the length documented during X-ray verification. Older methods of checking tube placement included observing aspirated GI contents or the administration of air with a syringe while auscultating (commonly referred to as the “whoosh test”). However, research has determined these methods are unreliable and should no longer be used to verify placement.Simons, S. R., & Abdallah, L. M. (2012). Bedside assessment of enteral tube placement: Aligning practice with evidence. American Journal of Nursing, 112(2), 40-46. https://doi.org/10.1097/01.naj.0000411178.07179.68,Boullata, J. I., Carrera, A. L., Harvey, L., Escuro, A. A., Hudson, L., Mays, A., McGinnis, C., Wessel, J. J., Bajpai, S., Beebe, M. L., Kinn, T. J., Klang, M. G., Lord, L., Martin, K., Pompeii‐Wolfe, C., Sullivan, J., Wood, A., Malone, A., & Guenter, P. (2017). ASPEN safe practices for enteral nutrition therapy. Journal of Parenteral and Enteral Nutrition, 41(1), 15-103. https://doi.org/10.1177/0148607116673053 In addition to verifying tube placement before administering feedings or medications, nurses perform additional interventions to prevent aspiration. The American Association of Critical‐Care Nurses recommends the following guidelines to reduce the risk for aspiration: - Maintain the head of the bed at 30°- 45° unless contraindicated - Use sedatives as sparingly as possible - Assess feeding tube placement at four‐hour intervals - Observe for change in the amount of external length of the tube - Assess for gastrointestinal intolerance at four‐hour intervalsSimons, S. R., & Abdallah, L. M. (2012). Bedside assessment of enteral tube placement: Aligning practice with evidence. American Journal of Nursing, 112(2), 40-46. https://doi.org/10.1097/01.naj.0000411178.07179.68,Boullata, J. I., Carrera, A. L., Harvey, L., Escuro, A. A., Hudson, L., Mays, A., McGinnis, C., Wessel, J. J., Bajpai, S., Beebe, M. L., Kinn, T. J., Klang, M. G., Lord, L., Martin, K., Pompeii‐Wolfe, C., Sullivan, J., Wood, A., Malone, A., & Guenter, P. (2017). ASPEN safe practices for enteral nutrition therapy. Journal of Parenteral and Enteral Nutrition, 41(1), 15-103. https://doi.org/10.1177/0148607116673053 Measurement of gastric residual volume (GRV) is often performed when a patient is receiving enteral feeding by using a 60-mL syringe to aspirate stomach contents through the tube. GRVs in the range of 200–500 mL have traditionally triggered nursing interventions, such as slowing or stopping the feeding, to reduce the patient’s risk of aspiration. However, according to recent research, it is not appropriate to stop enteral nutrition for GRVs less than 500 mL in the absence of other signs of intolerance because of the impact on the patient’s overall nutritional status. Additionally, the aspiration of gastric residual volumes can contribute to tube clogging. Follow agency policy regarding measuring gastric residual volume and implementing interventions to prevent aspiration.Simons, S. R., & Abdallah, L. M. (2012). Bedside assessment of enteral tube placement: Aligning practice with evidence. American Journal of Nursing, 112(2), 40-46. https://doi.org/10.1097/01.naj.0000411178.07179.68,Boullata, J. I., Carrera, A. L., Harvey, L., Escuro, A. A., Hudson, L., Mays, A., McGinnis, C., Wessel, J. J., Bajpai, S., Beebe, M. L., Kinn, T. J., Klang, M. G., Lord, L., Martin, K., Pompeii‐Wolfe, C., Sullivan, J., Wood, A., Malone, A., & Guenter, P. (2017). ASPEN safe practices for enteral nutrition therapy. Journal of Parenteral and Enteral Nutrition, 41(1), 15-103. https://doi.org/10.1177/0148607116673053 Patients receiving enteral nutrition should be monitored daily for signs of tube feeding intolerance, such as abdominal bloating, nausea, vomiting, diarrhea, cramping, and constipation. If cramping occurs during bolus feedings, it can be helpful to administer the enteral nutritional formula at room temperature to prevent symptoms. Notify the provider of signs of intolerance with anticipated prescription changes regarding the type of formula or the rate of administration. Electrolytes and blood glucose levels should also be monitored for signs of imbalances. Carbohydrates in tube feedings are absorbed quickly, so blood glucose levels are monitored, and elevated levels are typically treated with sliding scale insulin according to health care provider orders. Read about “Enteral Tube Management” in Open RN Nursing Skills. Parenteral Nutrition Parenteral nutrition is nutrition delivered through a central intravenous line, generally the subclavian or internal jugular vein, to patients who require nutritional supplementation but are not candidates for enteral nutrition. Parenteral nutrition is an intravenous solution containing glucose, amino acids, minerals, electrolytes, and vitamins. A lipid solution is typically given in a separate infusion in a hospital setting. This combination of solutions is called total parenteral nutrition because it supplies complete nutritional support. Parenteral nutrition is administered via an IV pump. Because parenteral nutrition consists of concentrated glucose, amino acids, and minerals, it is very irritating to the blood vessels. For this reason, a large central vein must be used for administration. The patient’s lab work must also be closely monitored for signs of nutrient excesses. See Figure 14.13“Tpn_3bag.jpg” by Tristanb in English Wikipedia is licensed under CC BY-SA 3.0 for an image of home parenteral nutrition formula. In this image are three compartments: one with glucose, one with amino acids, and one with lipids. The three compartments are kept separate to enable storage at room temperature, but are mixed together before use. Parenteral nutrition is typically used when the patient’s intestines or stomach is not working properly and must be bypassed, such as during paralytic ileus where peristalsis has completely stopped, or after postoperative bowel surgeries, such as bowel resection. It may also be prescribed for severe malnutrition, severe burns, metastatic cancer, liver failure, or hyperemesis with pregnancy. Implementing Interventions When implementing interventions to promote good nutrition, it is vital to consider the patient’s cultural and religious beliefs. Encourage patients to make healthy food selections based on their food preferences. If a patient has nutritional deficit, perform nursing interventions prior to mealtime to promote their appetite. For example, if the patient has symptoms of pain or nausea, administer medications prior to mealtime to manage these symptoms. Do not perform procedures that may affect the patient’s appetite, such as wound dressing changes, immediately prior to meal time. Manage the environment prior to the food arriving and remove any unpleasant odors or sights. For example, empty the trash can of used dressings or incontinence products. If the patient is out of the room when the meal tray arrives and the food becomes cold, reheat the food or order a new meal tray. When assisting patients to eat, help them to wash their hands and use the restroom if needed. Set the meal tray on an overbed table and open containers as needed. Encourage the patient to feed themselves as much as possible to promote independence. If a patient has vision impairments, explain the location of the food using the clock method. For example, “Your vegetables are at 9 o’clock, your potatoes are at 12 o’clock, and your meat is at 3 o’clock.” When feeding a patient, ask them what food they would like to eat first. Allow them to eat at their own pace with time between bites for thorough chewing and swallowing. If any signs of difficulty swallowing occur, such as coughing or gagging, stop the meal and notify the provider of suspected swallowing difficulties. Evaluation It is always important to evaluate the effectiveness of interventions implemented. Evaluation helps the nurse and care team determine if the interventions are appropriate for the patient or if they need to be revised. Table 14.3e provides a list of assessment findings indicating that alterations of nutritional status are improving with the planned interventions. Table 14.3e Evaluation of Alterations in Nutritional Status \| Imbalance \| How Do We Know It Is Improved? \| \|---\|---\| \| Imbalanced Nutrition: Less than Body Requirements \| Stable or increasing weight; sufficient daily calories; well-balanced meal intake; improved energy, appearance of hair, nails, skin, or vision \| \| Imbalanced Nutrition: More than Body Requirements \| Stable or decreasing weight, <5% body weight loss over 6 months, well-balanced meal intake \| 14.4 Putting It All Together Patient Scenario Mr. Curtis is a 47-year-old patient admitted to the hospital with increased weakness, fatigue, and dehydration. His skin appears dry, and tenting occurs when skin turgor is evaluated. He is currently undergoing chemotherapy treatment for multiple myeloma and has experienced weight loss of 10 pounds within the last two weeks. He describes that “nothing tastes good,” and he feels as if there is “metal taste in his mouth.” When he does eat small meals, he reports that he is often nauseous. The patient’s serum protein level is 3.1 g/dL. Applying the Nursing Process Assessment: The nurse identifies that the patient is experiencing signs of imbalanced nutrition with the signs of increased weakness, fatigue, and signs of dehydration such as skin tenting and dryness. The patient has demonstrated a significant weight loss over the past two weeks and reports “nothing tastes good” and “a metal taste in the mouth.” The patient also reports nausea after eating. His serum protein level reflects signs of malnutrition. Based on the assessment information that has been gathered, the following nursing care plan is created for Mr. Curtis: Nursing Diagnosis: Imbalanced Nutrition: Less Than Body Requirements r/t insufficient dietary intake as manifested by weight loss of 10 pounds in the last two weeks, skin tenting and dryness, reports of “nothing tastes good,” and serum protein of 3.1 g/dL. Overall Goal: The patient will demonstrate improvement in nutrition intake. SMART Expected Outcome: Mr. Curtis will eat 50% of offered meals and demonstrate dietary tolerance within 24 hours. Planning and Implementing Nursing Interventions: The nurse will validate the patient’s feelings regarding his current symptoms and provide emotional support. The nurse will determine the time of day when the patient’s appetite is highest and offer the highest calorie meal at that time. The nurse will offer high-calorie protein shakes to the patient at frequent intervals. The nurse will assess the patient’s food preferences and ensure that small frequent meals are offered that incorporate those preferences. The nurse will also encourage the use of plastic utensils and encourage the patient to eat mints or chew gum to minimize the metallic taste in the mouth. Sample Documentation: Mr. Curtis demonstrates signs of imbalanced nutrition: less than body requirements. He reported a significant weight loss of 10 pounds over the past two weeks associated with chemotherapy. He reports feeling nauseous following small meals. He also reports “nothing tastes good” and having “a metal taste in the mouth.” He demonstrates signs of weakness, fatigue, and dehydration. Interventions have been implemented to increase the patient’s nutritional intake. Evaluation: Twenty-four hours later, the nurse evaluates Mr. Curtis and finds he is able to consume 50% of breakfast with his preferred dietary items. Planned interventions will continue and the nurse plan to reevaluate his progress the following day. 14.5 Learning Activities Open Resources for Nursing (Open RN) Learning Activities (Answers to “Learning Activities” can be found in the “Answer Key” at the end of the book. Answers to interactive activity elements will be provided within the element as immediate feedback.) Scenario 1 Mr. Jones is a 67-year-old patient on the medical surgical floor who recently underwent a bowel resection. He is post-op Day 2 and has been NPO since surgery. He has been receiving IV fluids but has been asking about when he can resume eating. - What assessments should be performed to determine if the patient’s diet can be progressed? - What are the first steps during dietary transition from NPO status? Scenario 2“woman-1031000_960_720.jpg” by Free-Photos is licensed under CC0 Mrs. Casey is a 78 year-old widow who recently had a stroke and continues to experience mild right-sided weakness. See Figure 14.14 for an image of Mrs. Casey.“woman-1031000_960_720.jpg” by Free-Photos is licensed under CC0 She is currently receiving physical therapy in a long-term care facility and ambulates with the assistance of a walker. Mrs. Casey confides, “I am looking forward to going home, but I will miss the three meals a day here.” Her height is 5’2″ and she weighs 84 pounds. Her recent lab work results include the following: Hgb: 8.8 g/dL, WBC 3500, Magnesium 1.4 mg/dL, Albumin 10 g/dL - What is Mrs. Casey’s BMI and what does this number indicate? - Analyze Mrs. Casey’s recent lab work and interpret the findings. - Describe focused assessments the nurse should perform regarding Mrs. Casey’s nutritional status. - Create a PES nursing diagnosis statement for Mrs. Casey based on her nutritional status. - Create a SMART outcome statement for Mrs. Casey. - Outline planned nutritional interventions for Mrs. Casey while she is at the facility, as well as when she returns home. - How will you evaluate if your nursing care plan is successful for Mrs. Casey? An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=2076#h5p-48 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=2076#h5p-50 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=2076#h5p-92 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=2076#h5p-145 “Nutrition Case Study” by Susan Jensen for Lansing Community College are licensed under CC BY 4.0 XIV Glossary Open Resources for Nursing (Open RN) Body Mass Index (BMI): A measure of weight categories including underweight, normal weight, overweight, and obese taking height and weight into consideration. Calorie-dense foods: Foods with a substantial amount of calories and few nutrients. Carbohydrates: Sugars and starches that provide an important energy source, providing 4 kcal/g of energy. Chemical digestion: Breakdown of food with stomach acids, bile, and pancreatic enzymes for nutrient release. Chyme: Broken-down food that has undergone chemical digestion in the stomach. Complete proteins: Proteins with enough amino acids in enough quantities to perform necessary functions such as growth and tissue maintenance. These must be ingested in the diet. Complex carbohydrates: Larger molecules of polysaccharides that break down more slowly and release sugar into the bloodstream more slowly than simple carbohydrates. Dietary Reference Intakes (DRIs): Set requirements or limit amounts of a certain nutrient, including proteins, carbohydrates, fats, vitamins, minerals, and fiber. Dysphagia: Difficulty swallowing. Enteral nutrition: Liquid nutrition given through the gastrointestinal tract via a tube while bypassing chewing and swallowing. Essential nutrients: Nutrients that must be ingested from dietary intake. Essential nutrients cannot be synthesized by the body. Fat-soluble vitamins: Vitamins that dissolve in fats and oils and are stored in fat tissue and can build up in the liver, resulting in toxicity. Fat-soluble vitamins include vitamins A, D, E, and K. Fats: Fatty acids and glycerol that are essential for tissue growth, insulation, energy source, energy storage, and hormone production. Fats provide 9 kcal/g of energy. Glycemic index: A measure of how quickly plasma glucose levels are released into the bloodstream after carbohydrates are consumed. Incomplete proteins: Proteins that do not contain enough amino acids to sustain life. Incomplete proteins can be combined with other types of proteins to add to amino acids consumed to form complete protein combinations. Lactation: Breast milk production. Macrominerals: Minerals needed in larger amounts and measured in milligrams, grams, and milliequivalents. Macronutrients: Nutrients needed in larger amounts due to energy needs. Macronutrients include carbohydrates, proteins, and fats. Mastication: The chewing of food in the mouth. Mechanical digestion: Breaking food down into small chunks through chewing prior to swallowing. Nitrogen balance: The net loss or gain of nitrogen excreted compared to nitrogen taken into the body in the form of protein consumption; an indicator of protein status where a negative nitrogen balance equates to a protein deficit in the diet and a positive nitrogen balance equates to a protein excess in the diet. Nutrient-dense foods: Foods with a high proportion of nutritional value relative to calories contained in the food. Parenteral nutrition: An intravenous solution containing glucose, amino acids, minerals, electrolytes, and vitamins, along with supplemental lipids. Partially complete proteins: Proteins that have enough amino acids to sustain life, but not enough for tissue growth and maintenance. Typically interchanged with incomplete proteins. Peristalsis: Coordinated muscle movements in the esophagus that move food or liquid through the esophagus and into the stomach or coordinated muscle movements in the intestines that move food/waste products through the intestines. Proteins: Sources of peptides, amino acids, and some trace elements that provide 4 kcal/g of energy. Proteins are necessary for tissue repair, tissue function, growth, fluid balance, and clotting, as well as energy in the absence of sufficient intake of carbohydrates. Refined grains: Grains that have been processed to remove parts of the grain kernel and supply little fiber. Saturated fats: Fats derived from animal products, such as butter, tallow, and lard for cooking, or from meat products such as steak. Saturated fats are generally solid at room temperature and can raise cholesterol levels, contributing to heart disease. Simple carbohydrates: Small molecules of monosaccharides or disaccharides that break down quickly and raise blood glucose levels quickly. Trace minerals: Minerals needed in tiny amounts. Trans fats: Fats that have been altered through hydrogenation and as such are not in their natural state. Fat is changed to make it harder at room temperature and to make it have a longer shelf life and contributes to increased cholesterol and heart disease. Unsaturated fats: Fats derived from oils and plants, though chicken and fish contain some unsaturated fats as well. Unsaturated fats are healthier than saturated fats, and some containing omega-3 fatty acids are considered polyunsaturated fats and help lower LDL cholesterol levels. Water-soluble vitamins: Vitamins that are not stored in the body and include vitamin C and B-complex vitamins: B1 (thiamine), B2 (riboflavin), B3 (niacin), B6 (pyridoxine), B12 (cyanocobalamin), and B9 (folic acid, biotin, and pantothenic acid). Toxicity is rare as excess water-soluble vitamins are excreted in the urine. Whole grains: Grains with the entire grain kernel that supply more fiber than refined grains. Fluids and Electrolytes XV 15.1 Fluids and Electrolytes Introduction Open Resources for Nursing (Open RN) Learning Objectives - Describe variables that influence fluid and electrolyte balance - Identify factors related to fluid/electrolyte balance across the life span - Assess a patient’s nutritional and fluid/electrolyte status - Outline specific nursing interventions to promote fluid and electrolyte balance - Base decisions on the signs and symptoms of fluid volume excess and fluid volume deficit - Base decisions on the interpretation of diagnostic tests and lab values indicative of a disturbance in fluid and electrolyte balance - Identify evidence-based practices The human body maintains a delicate balance of fluids and electrolytes to help ensure proper functioning and homeostasis. When fluids or electrolytes become imbalanced, individuals are at risk for organ system dysfunction. If an imbalance goes undetected and is left untreated, organ systems cannot function properly and ultimately death will occur. Nurses must be able to recognize subtle changes in fluid or electrolyte balances in their patients so they can intervene promptly. Timely assessment and intervention prevent complications and save lives. 15.2 Basic Fluid and Electrolyte Concepts Open Resources for Nursing (Open RN) Before learning about how to care for patients with fluid and electrolyte imbalances, it is important to understand the physiological processes of the body’s regulatory mechanisms. The body is in a constant state of change as fluids and electrolytes are shifted in and out of cells within the body in an attempt to maintain a nearly perfect balance. A slight change in either direction can have significant consequences on various body systems. Body Fluids Body fluids consist of water, electrolytes, blood plasma and component cells, proteins, and other soluble particles called solutes. Body fluids are found in two main areas of the body called intracellular and extracellular compartments. See Figure 15.1“Cellular_Fluid_Content.jpg” by Welcome1To1The1Jungle is licensed under CC BY 3.0 for an illustration of intracellular and extracellular compartments. Intracellular fluids (ICF) are found inside cells and are made up of protein, water, electrolytes, and solutes. The most abundant electrolyte in intracellular fluid is potassium. Intracellular fluids are crucial to the body’s functioning. In fact, intracellular fluid accounts for 60% of the volume of body fluids and 40% of a person’s total body weight!Fluid. (2012). In Britannica. https://www.britannica.com/science/fluid-biology Extracellular fluids (ECF) are fluids found outside of cells. The most abundant electrolyte in extracellular fluid is sodium. The body regulates sodium levels to control the movement of water into and out of the extracellular space due to osmosis. Extracellular fluids can be further broken down into various types. The first type is known as intravascular fluid that is found in the vascular system that consists of arteries, veins, and capillary networks. Intravascular fluid is whole blood volume and also includes red blood cells, white blood cells, plasma, and platelets. Intravascular fluid is the most important component of the body’s overall fluid balance. Loss of intravascular fluids causes the nursing diagnosis Deficient Fluid Volume, also referred to as hypovolemia. Intravascular fluid loss can be caused by several factors, such as excessive diuretic use, severe bleeding, vomiting, diarrhea, and inadequate oral fluid intake. If intravascular fluid loss is severe, the body cannot maintain adequate blood pressure and perfusion of vital organs. This can result in hypovolemic shock and cellular death when critical organs do not receive an oxygen-rich blood supply needed to perform cellular function. A second type of extracellular fluid is interstitial fluid that refers to fluid outside of blood vessels and between the cells. For example, if you have ever cared for a patient with heart failure and noticed increased swelling in the feet and ankles, you have seen an example of excess interstitial fluid referred to as edema. The remaining extracellular fluid, also called transcellular fluid, refers to fluid in areas such as cerebrospinal, synovial, intrapleural, and gastrointestinal system.This work is a derivative of StatPearls by Brinkman, Dorius, and Sharma and is licensed under CC BY 4.0 Fluid Movement Fluid movement occurs inside the body due to osmotic pressure, hydrostatic pressure, and osmosis. Proper fluid movement depends on intact and properly functioning vascular tissue lining, normal levels of protein content within the blood, and adequate hydrostatic pressures inside the blood vessels. Intact vascular tissue lining prevents fluid from leaking out of the blood vessels. Protein content of the blood (in the form of albumin) causes oncotic pressure that holds water inside the vascular compartment. For example, patients with decreased protein levels (i.e., low serum albumin) experience edema due to the leakage of intravascular fluid into interstitial areas because of decreased oncotic pressure. Hydrostatic pressure is defined as pressure that a contained fluid exerts on what is confining it. In the intravascular fluid compartment, hydrostatic pressure is the pressure exerted by blood against the capillaries. Hydrostatic pressure opposes oncotic pressure at the arterial end of capillaries, where it pushes fluid and solutes out into the interstitial compartment. On the venous end of the capillary, hydrostatic pressure is reduced, which allows oncotic pressure to pull fluids and solutes back into the capillary.This work is a derivative of StatPearls by Brinkman, Dorius, and Sharma and is licensed under CC BY 4.0,“Hydrostatic Pressure” by Ann Lawrie is licensed under CC BY-NC 2.0 See Figure 15.2“Capillary_microcirculation.jpg” by Kes47 is in the Public Domain for an illustration of hydrostatic pressure and oncotic pressure in a capillary. Filtration occurs when hydrostatic pressure pushes fluids and solutes through a permeable membrane so they can be excreted. An example of this process is fluid and waste filtration through the glomerular capillaries in the kidneys. This filtration process within the kidneys allows excess fluid and waste products to be excreted from the body in the form of urine. Fluid movement is also controlled through osmosis. Osmosis is water movement through a semipermeable membrane, from an area of lesser solute concentration to an area of greater solute concentration, in an attempt to equalize the solute concentrations on either side of the membrane. Only fluids and some particles dissolved in the fluid are able to pass through a semipermeable membrane; larger particles are blocked from getting through. Because osmosis causes fluid to travel due to a concentration gradient and no energy is expended during the process, it is referred to as passive transport.BBC. (n.d.) Movement across cell membranes. https://www.bbc.co.uk/bitesize/guides/zc9tyrd/revision/5 See Figure 15.3“0307_Osmosis.jpg” by OpenStax is licensed under CC BY 4.0. Access for free at https://openstax.org/books/anatomy-and-physiology/pages/3-1-the-cell-membrane for an illustration of osmosis where water has moved to the right side of the membrane to equalize the concentration of solutes on that side with the left side. Osmosis causes fluid movement between the intravascular, interstitial, and intracellular fluid compartments based on solute concentration. For example, recall a time when you have eaten a large amount of salty foods. The sodium concentration of the blood becomes elevated. Due to the elevated solute concentration within the bloodstream, osmosis causes fluid to be pulled into the intravascular compartment from the interstitial and intracellular compartments to try to equalize the solute concentration. As fluid leaves the cells, they shrink in size. The shrinkage of cells is what causes many symptoms of dehydration, such as dry, sticky mucous membranes. Because the brain cells are especially susceptible to fluid movement due to osmosis, a headache may occur if adequate fluid intake does not occur. Solute Movement Solute movement is controlled by diffusion, active transport, and filtration. Diffusion is the movement of molecules from an area of higher concentration to an area of lower concentration to equalize the concentration of solutes throughout an area. (Note that diffusion is different from osmosis because osmosis is the movement of fluid whereas diffusion is the movement of solutes.) See Figure 15.4“Simple_Diffusion.png” by Elizabeth2424 is licensed under CC BY-SA 3.0 for an image of diffusion. Because diffusion travels down a concentration gradient, the solutes move freely without energy expenditure. An example of diffusion is the movement of inhaled oxygen molecules from alveoli to the capillaries in the lungs so that they can be distributed throughout the body. Active transport, unlike diffusion, involves moving solutes and ions across a cell membrane from an area of lower concentration to an area of higher concentration. Because active transport moves solutes against a concentration gradient to prevent an overaccumulation of solutes in an area, energy is required for this process to take place.BBC. (n.d.) Movement across cell membranes. https://www.bbc.co.uk/bitesize/guides/zc9tyrd/revision/5 An example of active transport is the sodium-potassium pump, which uses energy to maintain higher levels of sodium in the extracellular fluid and higher levels of potassium in the intracellular fluid. See Figure 15.5“Sodium-potassium_pump_and_diffusion.png” by BruceBlaus.com staff is licensed under CC BY 3.0 for an image of diffusion and the sodium-potassium pump regulating sodium and potassium levels in the extracellular and intracellular compartments. Recall that sodium (Na+) is the primary electrolyte in the extracellular space and potassium (K+) is the primary electrolyte in the intracellular space. Fluid and Electrolyte Regulation The body must carefully regulate intravascular fluid accumulation and excretion to prevent fluid volume excesses or deficits and maintain adequate blood pressure. Water balance is regulated by several mechanisms including ADH, thirst, and the Renin-Angiotensin-Aldosterone System (RAAS). Fluid intake is regulated by thirst. As fluid is lost and the sodium level increases in the intravascular space, serum osmolality increases. Serum osmolality is a measure of the concentration of dissolved solutes in the blood. Osmoreceptors in the hypothalamus sense increased serum osmolarity levels and trigger the release of ADH (antidiuretic hormone) in the kidneys to retain fluid. The osmoreceptors also produce the feeling of thirst to stimulate increased fluid intake. However, individuals must be able to mentally and physically respond to thirst signals to increase their oral intake. They must be alert, fluids must be accessible, and the person must be strong enough to reach for fluids. When a person is unable to respond to thirst signals, dehydration occurs. Older individuals are at increased risk of dehydration due to age-related impairment in thirst perception. The average adult intake of fluids is about 2,500 mL per day from both food and drink. An increased amount of fluids is needed if the patient has other medical conditions causing excessive fluid loss, such as sweating, fever, vomiting, diarrhea, and bleeding. The Renin-Angiotensin-Aldosterone System (RAAS) plays an important role in regulating fluid output and blood pressure. See Figure 15.6“2626_Renin_Aldosterone_Angiotensin.jpg” by OpenStax is licensed under CC BY 3.0. Access for free at https://openstax.org/books/anatomy-and-physiology/pages/25-4-microscopic-anatomy-of-the-kidney for an illustration of the Renin-Angiotensin-Aldosterone System (RAAS). When there is decreased blood pressure (which can be caused by fluid loss), specialized kidney cells make and secrete renin into the bloodstream. Renin acts on angiotensinogen released by the liver and converts it to angiotensin I, which is then converted to angiotensin II. Angiotensin II does a few important things. First, angiotensin II causes vasoconstriction to increase blood flow to vital organs. It also stimulates the adrenal cortex to release aldosterone. Aldosterone is a steroid hormone that triggers increased sodium reabsorption by the kidneys and subsequent increased serum osmolality in the bloodstream. As you recall, increased serum osmolality causes osmosis to move fluid into the intravascular compartment in an effort to equalize solute particles. The increased fluids in the intravascular compartment increase circulating blood volume and help raise the person’s blood pressure. An easy way to remember this physiological process is “aldosterone saves salt” and “water follows salt.”This work is a derivative of StatPearls by Fountain and Lappin and is licensed under CC BY 4.0 Fluid output occurs mostly through the kidneys in the form of urine. Fluid is also lost through the skin as perspiration, through the gastrointestinal tract in the form of stool, and through the lungs during respiration. Forty percent of daily fluid output occurs due to these “insensible losses” through the skin, gastrointestinal tract, and lungs and cannot be measured. The remaining 60% of daily fluid output is in the form of urine. Normally, the kidneys produce about 1,500 mL of urine per day when fluid intake is adequate. Decreased urine production is an early sign of dehydration or kidney dysfunction. It is important for nurses to assess urine output in patients at risk. If a patient demonstrates less than 30 mL/hour (or 0.5 mL/kg/hour) of urine output over eight hours, the provider should be notified for prompt intervention. See Figure 15.7“Water_balance.png” by David Walsh and Alan Sved is licensed under CC BY-SA 4.0 for an illustration of an average adult’s daily water balance of 2,500 mL fluid intake balanced with 2,500 mL fluid output. Fluid Imbalance Two types of fluid imbalances are excessive fluid volume (also referred to as hypervolemia) and deficient fluid volume (also referred to as hypovolemia). These imbalances primarily refer to imbalances in the extracellular compartment, but can cause fluid movement in the intracellular compartments based on the sodium level of the blood. Excessive Fluid Volume Excessive fluid volume (also referred to as hypervolemia) occurs when there is increased fluid retained in the intravascular compartment. Patients at risk for developing excessive fluid volume are those with the following conditions: - Heart Failure - Kidney Failure - Cirrhosis - PregnancyLewis, J. L., III. (June 2020). Volume overload. Merck Manual Professional Version. https://www.merckmanuals.com/professional/endocrine-and-metabolic-disorders/fluid-metabolism/volume-overload Symptoms of fluid overload include pitting edema, ascites, and dyspnea and crackles from fluid in the lungs. Edema is swelling in dependent tissues due to fluid accumulation in the interstitial spaces. Ascites is fluid retained in the abdomen. Treatment depends on the cause of the fluid retention. Sodium and fluids are typically restricted and diuretics are often prescribed to eliminate the excess fluid. For more information about the nursing care of patients with excessive fluid volume, see the “Applying the Nursing Process” section. Deficient Fluid Volume Deficient fluid volume (also referred to as hypovolemia or dehydration) occurs when loss of fluid is greater than fluid input. Common causes of deficient fluid volume are diarrhea, vomiting, excessive sweating, fever, and poor oral fluid intake. Individuals who have a higher risk of dehydration include the following: - Older adults - Infants and children - Patients with chronic diseases such as diabetes mellitus and kidney disease - Patients taking diuretics and other medications that cause increased urine output - Individuals who exercise or work outdoors in hot weatherMedlinePlus [Internet]. Bethesda (MD): National Library of Medicine (US); Dehydration; [updated 2020, Oct 1; reviewed 2016, Apr 15; cited 2020, Aug 5]. https://medlineplus.gov/dehydration.html In adults, symptoms of dehydration are as follows: - Feeling very thirsty - Dry mouth - Headache - Dry skin - Urinating and sweating less than usual - Dark, concentrated urine - Feeling tired - Changes in mental status - Dizziness due to decreased blood pressure - Elevated heart rateMedlinePlus [Internet]. Bethesda (MD): National Library of Medicine (US); Dehydration; [updated 2020, Oct 1; reviewed 2016, Apr 15; cited 2020, Aug 5]. https://medlineplus.gov/dehydration.html In infants and young children, additional symptoms of dehydration include the following: - Crying without tears - No wet diapers for three hours or more - Being unusually sleepy or drowsy - Irritability - Eyes that look sunken - Sunken fontanelMedlinePlus [Internet]. Bethesda (MD): National Library of Medicine (US); Dehydration; [updated 2020, Oct 1; reviewed 2016, Apr 15; cited 2020, Aug 5]. https://medlineplus.gov/dehydration.html Dehydration can be mild and treated with increased oral intake such as water or sports drinks. Severe cases can be life-threatening and require the administration of intravenous fluids. For more information about water balance and fluid movement, review the following video. Video Review of Fluid and ElectrolytesForciea, B. (2017, April 21). Fluids and electrolytes: Water. [Video]. YouTube. All rights reserved. Video used with permission. https://youtu.be/VMxmDeduKR0 15.3 Intravenous Solutions Open Resources for Nursing (Open RN) When patients experience deficient fluid volume, intravenous (IV) fluids are often prescribed. IV fluid restores fluid to the intravascular compartment, and some IV fluids are also used to facilitate the movement of fluid between compartments due to osmosis. There are three types of IV fluids: isotonic, hypotonic, and hypertonic. Isotonic Solutions Isotonic solutions are IV fluids that have a similar concentration of dissolved particles as blood. An example of an isotonic IV solution is 0.9% Normal Saline (0.9% NaCl). Because the concentration of the IV fluid is similar to the blood, the fluid stays in the intravascular space and osmosis does not cause fluid movement between compartments. See Figure 15.8“Blausen_0685_OsmoticFlow_Isotonic.png” by BruceBlaus.com staff is licensed under CC BY 3.0 for an illustration of isotonic IV solution administration with no osmotic movement of fluid with cells. Isotonic solutions are used for patients with fluid volume deficit (also called hypovolemia) to raise their blood pressure. However, infusion of too much isotonic fluid can cause excessive fluid volume (also referred to as hypervolemia). Hypotonic Solutions Hypotonic solutions have a lower concentration of dissolved solutes than blood. An example of a hypotonic IV solution is 0.45% Normal Saline (0.45% NaCl). When hypotonic IV solutions are infused, it results in a decreased concentration of dissolved solutes in the blood as compared to the intracellular space. This imbalance causes osmotic movement of water from the intravascular compartment into the intracellular space. For this reason, hypotonic fluids are used to treat cellular dehydration. See Figure 15.9“Blausen_0684_OsmoticFlow_Hypotonic.png” by BruceBlaus.com staff is licensed under CC BY 3.0 for an illustration of the osmotic movement of fluid into a cell when a hypotonic IV solution is administered, causing lower concentration of solutes (pink molecules) in the bloodstream compared to within the cell. However, if too much fluid moves out of the intravascular compartment into cells, cerebral edema can occur. It is also possible to cause worsening hypovolemia and hypotension if too much fluid moves out of the intravascular space and into the cells. Therefore, patient status should be monitored carefully when hypotonic solutions are infused. Hypertonic Solutions Hypertonic solutions have a higher concentration of dissolved particles than blood. An example of hypertonic IV solution is 3% Normal Saline (3% NaCl). When infused, hypertonic fluids cause an increased concentration of dissolved solutes in the intravascular space compared to the cells. This causes the osmotic movement of water out of the cells and into the intravascular space to dilute the solutes in the blood. See Figure 15.10“Blausen_0683_OsmoticFlow_Hypertonic.png” by BruceBlaus.com staff is licensed under CC BY 3.0 for an illustration of osmotic movement of fluid out of a cell when hypertonic IV fluid is administered due to a higher concentration of solutes (pink molecules) in the bloodstream compared to the cell. When administering hypertonic fluids, it is essential to monitor for signs of hypervolemia such as breathing difficulties and elevated blood pressure. Additionally, if hypertonic solutions with sodium are given, the patient’s serum sodium level should be closely monitored.Harris, H. (2011). I.V. fluids: What nurses need to know. Nursing2017, 41(5), 30-38. See Table 15.3 for a comparison of types of IV solutions, their uses, and nursing considerations. See Figure 15.11“Osmotic pressure on blood cells diagram.svg” by LadyofHats is in the Public Domain for an illustration comparing how different types of IV solutions affect red blood cell size. Table 15.3 Comparison of IV SolutionsHarris, H. (2011). I.V. fluids: What nurses need to know. Nursing2017, 41(5), 30-38. \| Type \| IV Solution \| Uses \| Nursing Considerations \| \| Isotonic \| 0.9% Normal Saline (0.9% NaCl) \| Fluid resuscitation for hemorrhaging, severe vomiting, diarrhea, GI suctioning losses, wound drainage, mild hyponatremia, or blood transfusions. \| Monitor closely for hypervolemia, especially with heart failure or renal failure. \| \| Isotonic \| Lactated Ringer’s Solution (LR) \| Fluid resuscitation, GI tract fluid losses, burns, traumas, or metabolic acidosis. Often used during surgery. \| Should not be used if serum pH is greater than 7.5 because it will worsen alkalosis. May elevate potassium levels if used with renal failure. \| \| Isotonic \| 5% Dextrose in Water (D5W) starts as isotonic and then changes to hypotonic when dextrose is metabolized \| Provides free water to help renal excretion of solutes, hypernatremia, and some dextrose supplementation. \| Should not be used for fluid resuscitation because after dextrose is metabolized, it becomes hypotonic and leaves the intravascular space, causing brain swelling. Used to dilute plasma electrolyte concentrations. \| \| Hypotonic \| 0.45% Sodium Chloride (0.45% NaCl) \| Used to treat intracellular dehydration and hypernatremia and to provide fluid for renal excretion of solutes. \| Monitor closely for hypovolemia, hypotension, or confusion due to fluid shifting into the intracellular space, which can be life-threatening. Avoid use in patients with liver disease, trauma, and burns to prevent hypovolemia from worsening. Monitor closely for cerebral edema. \| \| Hypotonic \| 5% Dextrose in Water (D5W) \| Provides free water to promote renal excretion of solutes and treat hypernatremia, as well as some dextrose supplementation. \| Monitor closely for hypovolemia, hypotension, or confusion due to fluid shifting out of the intravascular space, which can be life-threatening. Avoid use in patients with liver disease, trauma, and burns to prevent hypovolemia from worsening. Monitor closely for cerebral edema. \| \| Hypertonic \| 3% Sodium Chloride (3% NaCl) \| Used to treat severe hyponatremia and cerebral edema. \| Monitor closely for hypervolemia, hypernatremia, and associated respiratory distress. Do not use it with patients experiencing heart failure, renal failure, or conditions caused by cellular dehydration because it will worsen these conditions. \| \| Hypertonic \| 5% Dextrose and 0.45% Sodium Chloride (D50.45% NaCl) \| Used to treat severe hyponatremia and cerebral edema. \| Monitor closely for hypervolemia, hypernatremia, and associated respiratory distress. Do not use it with patients experiencing heart failure, renal failure, or conditions caused by cellular dehydration because it will worsen these conditions. \| \| Hypertonic \| 5% Dextrose and Lactated Ringer’s (D5LR) D10 \| Used to treat severe hyponatremia and cerebral edema. \| Monitor closely for hypervolemia, hypernatremia, and associated respiratory distress. Do not use it with patients experiencing heart failure, renal failure, or conditions caused by cellular dehydration because it will worsen these conditions. \| Osmolarity is defined as the proportion of dissolved particles in an amount of fluid and is generally the term used to describe body fluids. As the dissolved particles become more concentrated, the osmolarity increases. Osmolality refers to the proportion of dissolved particles in a specific weight of fluid. The terms osmolarity and osmolality are often used interchangeably in clinical practice. 15.4 Electrolytes Open Resources for Nursing (Open RN) Electrolytes play an important role in bodily functions and fluid regulation. There is a very narrow target range for normal electrolyte values, and slight abnormalities can have devastating consequences. For this reason, it is crucial to understand normal electrolyte ranges, causes of electrolyte imbalances, signs and symptoms of imbalances, and appropriate treatments. Sodium Sodium levels in the blood typically range from 136-145 mEq/L.Lab Tests Online. (2019). Sodium. https://labtestsonline.org/tests/sodium Refer to each agency’s normal reference range on the lab report. Sodium is the most abundant electrolyte in the extracellular fluid (ECF) and is maintained by the sodium-potassium pump. Sodium plays an important role in maintaining adequate fluid balance in the intravascular and interstitial spaces. See the “Fluid and Electrolyte Regulation” section of this chapter for more information about how the body regulates sodium and water balance. Hypernatremia refers to an elevated sodium level in the blood. Typically, hypernatremia is caused by excess water loss due to lack of fluid intake, vomiting, or diarrhea. As you recall, elevated sodium levels in the blood cause the osmotic movement of water out of the cells to dilute the blood. This causes the body’s cells to shrink, referred to as cellular dehydration. This fluid shift can have a significant impact on various organs within the body and is especially notable in the patient’s neurological function. As fluid shifts out of the brain cells, the nurse may notice symptoms such as confusion, irritability, lethargy, and even seizures. Other signs and symptoms of hypernatremia include severe thirst and sticky mucous membranes. See Figure 15.12“thirsty-4294629_960_720.png” by Conmongt is licensed under CC0for an illustration of a patient with severe thirst due to hypernatremia. Treatment for hypernatremia includes decreasing sodium intake, increasing oral water intake, and rehydrating with a hypotonic IV solution.Lewis, J. L., III. (April 2020). Hypernatremia. Merck Manual Professional Version. https://www.merckmanuals.com/professional/endocrine-and-metabolic-disorders/electrolyte-disorders/hypernatremia,This work is a derivative of StatPearls by Brinkman, Dorius, and Sharma and is licensed under CC BY 4.0 Hyponatremia refers to a decreased sodium level in the blood. Hyponatremia can be caused by excess water intake or excessive administration of hypotonic IV solutions. For example, a marathon runner who only rehydrates with water (without other fluids with solutes like Gatorade) can develop hyponatremia. As with hypernatremia, altered sodium levels often cause neurological symptoms due to the movement of water into brain cells, causing them to swell. Symptoms of hyponatremia are headache, confusion, seizures, and coma. Treatment for hyponatremia depends on the cause and often consists of limiting water intake or discontinuing administration of hypotonic IV fluids. If hyponatremia is severe, a hypertonic IV saline solution may be prescribed to gradually raise the patient’s sodium level.Lewis, J. L., III. (April 2020). Hyponatremia. Merck Manual Professional Version. https://www.merckmanuals.com/professional/endocrine-and-metabolic-disorders/electrolyte-disorders/hyponatremia Video Review of Fluids and Electrolytes: SodiumForciea, B.(2017, April 24). Fluids and electrolytes sodium. [Video]. YouTube. All Rights Reserved. Video used with permission. https://youtu.be/ar-WrfC7SJs Potassium Potassium levels normally range from 3.5 to 5.1 mEq/L.Lab Tests Online. (2019). Potassium. https://labtestsonline.org/tests/potassium Refer to each agency’s normal reference range on the lab report. Potassium is the most abundant electrolyte in intracellular fluid and is maintained inside the cell by the sodium-potassium pump. Potassium is regulated by aldosterone in the kidneys and is obtained in the diet through consumption of foods such as bananas, oranges, and tomatoes. See Figure 15.13“2711_Aldosterone_Feedback_Loop-01.jpg” by OpenStax College is licensed under CC BY 3.0. Access for free at https://openstax.org/books/anatomy-and-physiology/pages/26-3-electrolyte-balance for an illustration of potassium regulation by aldosterone. Recall that aldosterone causes reabsorption of sodium and excretion of potassium in the distal tubule of the kidneys. In response to potassium levels rising or sodium levels falling in the bloodstream, the adrenal cortex releases aldosterone and targets the kidneys. In response, the kidneys excrete potassium and reabsorb sodium. Potassium is also impacted by the hormone insulin that moves potassium into the cells from the ECF.This work is a derivative of Anatomy & Physiology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/anatomy-and-physiology/pages/1-introduction Potassium is necessary for normal cardiac function, neural function, and muscle contractility, including effective contractility of the cardiac muscles. Abnormal potassium levels can cause significantly abnormal heart rhythms and contractility. Potassium is poorly conserved by the body and much is lost with urine output. For this reason, it is often necessary to provide potassium supplements when administering loop and thiazide diuretics because potassium is excreted from the kidneys along with water.Lewis, J. L., III. (April 2020). Overview of disorders of potassium concentration. Merck Manual Professional Version. https://www.merckmanuals.com/professional/endocrine-and-metabolic-disorders/electrolyte-disorders/overview-of-disorders-of-potassium-concentration Potassium supplementation can be given orally or by IV infusion mixed with fluids. Potassium must NEVER be administered IV push because it can immediately stop the heart. Hyperkalemia refers to increased potassium levels in the blood. Hyperkalemia can be caused by kidney failure, metabolic acidosis, and administration of potassium-sparing diuretics or oral/intravenous potassium supplements. Signs and symptoms of hyperkalemia are generally cardiac in nature and include irritability, cramping, diarrhea, and electrocardiogram (ECG) abnormalities. As hyperkalemia worsens, ECG abnormalities may progress to cardiac dysrhythmias and cardiac arrest. Treatment for hyperkalemia depends on the severity of the hyperkalemia symptoms. For mild symptoms, decreased potassium intake in the diet is helpful. Adjustment to medications contributing to increased levels of potassium may be indicated. For severe symptoms, administration of sodium polystyrene sulfonate (Kayexalate) orally or rectally helps bind excess potassium so it is excreted through the GI tract. Insulin may be administered to push potassium into cells and decrease serum potassium levels. When administering an insulin infusion, it is important to monitor blood glucose levels closely, often hourly per agency policy. The patient often requires supplemental IV dextrose to prevent low blood sugar levels when insulin is used for potassium reduction. IV calcium gluconate may also be given to prevent excess potassium from affecting cardiac muscle. This is a temporary measure and wears off quickly but allows time for other treatments to take effect and lower potassium levels before cardiac arrest develops. For severe symptomatic hyperkalemia, temporary hemodialysis may also be used to quickly decrease potassium levels.Lewis, J. L., III. (April 2020). Hyperkalemia. Merck Manual Professional Version. https://www.merckmanuals.com/professional/endocrine-and-metabolic-disorders/electrolyte-disorders/hyperkalemia Hypokalemia refers to decreased potassium level in the blood. Hypokalemia can be caused by excessive vomiting, diarrhea, potassium-wasting diuretics, and insulin use, as well as lack of potassium in the diet. Signs and symptoms of hypokalemia include weakness, arrhythmias, lethargy, and a thready pulse. View helpful mnemonics for hypokalemia using the following hyperlink. Treatment for hypokalemia includes increasing oral intake of potassium in the diet and oral or IV potassium in fluids supplementation. It is important to remember that administering IV potassium too quickly can cause cardiac arrest. In fact, potassium is one of the ingredients used during lethal injection to stop the heart. View helpful mnemonics for hypokalemia at Hypokalemia NCLEX Review Notes. Video Review About PotassiumForciea, B. (2017, April 26). Fluids and electrolytes potassium. [Video]. YouTube. All rights reserved. Video used with permission. https://youtu.be/SNAiGaaYkvs Calcium Calcium levels normally range from 8.6-10.2 mg/dL.Lab Tests Online (2017). Calcium. https://labtestsonline.org/tests/calcium Refer to each agency’s normal reference range on the lab report. Calcium circulates in the bloodstream, but the majority is stored in bones. Calcium is important for bone and teeth structure, nerve transmission, and muscle contraction. Calcium excretion and reabsorption are regulated by the parathyroid hormone (PTH) that is secreted from the parathyroid glands near the thyroid. See Figure 15.14“1814_The_Parathyroid_Glands.jpg” by OpenStax is licensed under CC BY 3.0. Access for free at https://openstax.org/books/anatomy-and-physiology/pages/17-5-the-parathyroid-glands for an illustration of the parathyroid glands. As PTH is secreted in response to low calcium levels in the blood, calcium is reabsorbed in both the kidneys and the intestine and released from the bones to increase serum calcium levels. Calcium is also affected by dietary intake and physical activity. Activity causes calcium to move into bones whereas immobility causes the release of calcium from bones, which cases them to become weak. Dietary sources of calcium include dairy products, green leafy vegetables, sardines, and whole grains.Lewis, J. L., III. (April 2020). Overview of disorders of calcium concentration. Merck Manual Professional Version. https://www.merckmanuals.com/professional/endocrine-and-metabolic-disorders/electrolyte-disorders/overview-of-disorders-of-calcium-concentration Hypercalcemia refers to an increased calcium level. It can be caused by prolonged immobilization that allows calcium to leach out of the bones and into the serum. Additionally, there are many types of cancers that may cause excessive calcium release from bones. Hypercalcemia can also be caused by hyperparathyroidism and parathyroid tumors, which can cause too much PTH secretion, causing too much calcium to be reabsorbed in the kidneys and intestines and released from bone. Signs and symptoms of hypercalcemia often impact the gastrointestinal and musculoskeletal systems. These symptoms include nausea, vomiting, constipation, increased thirst and/or urination, and skeletal muscle weakness. Treatment for hypercalcemia includes decreasing calcium intake in the diet, phosphate supplementation (which has an inverse relationship to calcium), hemodialysis, surgical removal of the parathyroid gland (if hyperparathyroidism is causing the hypercalcemia), and weight-bearing exercises as tolerated.Lewis, J. L., III. (April 2020). Hypercalcemia. Merck Manual Professional Version. https://www.merckmanuals.com/professional/endocrine-and-metabolic-disorders/electrolyte-disorders/hypercalcemia Hypocalcemia refers to a decreased calcium level in the blood. Hypocalcemia can be caused by hypoparathyroidism where not enough PTH is excreted, causing a decreased reabsorption of calcium and decreased release of calcium from the bones. Hypocalcemia is also caused by vitamin D deficiency and renal disease. Because phosphorus is inversely related to calcium, an abnormally high phosphorus level as seen with renal failure can also result in hypocalcemia. Signs and symptoms of hypocalcemia often impact the musculoskeletal and nervous systems. These include paresthesias (numbness and tingling) of the lips, tongue, hands and feet, muscle cramps, and tetany. Chvostek’s sign is a classic sign of acute hypocalcemia and is an involuntary twitching of facial muscles when the facial nerve is tapped. A second classic sign of acute hypocalcemia is Trousseau’s sign where a hand spasm is caused by inflating a blood pressure cuff to a level above systolic pressure for 3 minutes. See a video of a patient experiencing Chvostek’s and Trousseau’s signs in the hyperlink below. Treatment of hypocalcemia includes increasing oral intake of dietary calcium and vitamin D and oral or IV calcium supplementation and decreasing the phosphorus level if it is elevated.Lewis, J. L., III. (April 2020). Hypocalcemia. Merck Manual Professional Version. https://www.merckmanuals.com/professional/endocrine-and-metabolic-disorders/electrolyte-disorders/hypocalcemia View a video of a patient exhibiting Chvostek’s Sign and Trousseau’s Signs of hypocalcemia. Phosphorus Phosphorus levels typically range from 2.5-4.0 mg/dL. Refer to each agency’s normal reference range on the lab report. Phosphorus is stored in the bones and is predominantly found in the ICF with small amounts in the ECF. Phosphorus is important in energy metabolism, RNA and DNA formation, nerve function, muscle contraction, and for bone, teeth, and membrane building and repair. Phosphorus is excreted by the kidneys and absorbed by the intestines. Dietary phosphorus sources include dairy products, fruits, vegetables, meat, and cereal.Lewis, J. L., III. (April 2020). Overview of disorders of phosphate concentration. Merck Manual Professional Version. https://www.merckmanuals.com/professional/endocrine-and-metabolic-disorders/electrolyte-disorders/overview-of-disorders-of-phosphate-concentration Hyperphosphatemia refers to an increased phosphorus level in the blood and can be caused by kidney disease, crush injuries, or overuse of phosphate-containing enemas. Hyperphosphatemia itself is usually asymptomatic, but signs of associated hypocalcemia may be present due to the inverse relationship between phosphorus and calcium. Treatment for hyperphosphatemia includes decreasing intake of phosphorus, administration of phosphate-binder medications to help with excretion, and hemodialysis.Lewis, J. L., III. (April 2020). Hyperphosphatemia. Merck Manual Professional Version. https://www.merckmanuals.com/professional/endocrine-and-metabolic-disorders/electrolyte-disorders/hyperphosphatemia Hypophosphatemia is a decreased phosphorus level in the blood. Acute hypophosphatemia can be caused by acute alcohol abuse, burns, diuretic use, respiratory alkalosis, resolving diabetic ketoacidosis, and starvation. Chronic hypophosphatemia is caused by hyperparathyroidism, vitamin D deficiency, prolonged use of phosphate binders, and hypomagnesemia or hypokalemia. Hypophosphatemia is usually asymptomatic, but in severe cases, it can cause muscle weakness, anorexia, encephalopathy, seizures, and death. Treatment for hypophosphatemia includes treating what is causing the imbalance, oral or IV phosphorus replacement, and increased phosphate-containing foods in the diet.Lewis, J. L., III. (April 2020). Hypophosphatemia. Merck Manual Professional Version. https://www.merckmanuals.com/professional/endocrine-and-metabolic-disorders/electrolyte-disorders/hypophosphatemia Magnesium Magnesium levels typically range from 1.5-2.4 mEq/L. Refer to each agency’s reference range on the lab report. Magnesium is essential for normal cardiac, nerve, muscle, and immune system functioning. About half of the body’s magnesium is stored in the bones. About 1% is stored in ECF and the rest is found in ICF.Lewis, J. L., III. (April 2020). Overview of disorders of magnesium concentration. Merck Manual Professional Version. https://www.merckmanuals.com/professional/endocrine-and-metabolic-disorders/electrolyte-disorders/overview-of-disorders-of-magnesium-concentration Dietary sources of magnesium include green leafy vegetables, citrus, peanut butter, almonds, legumes, and chocolate. Hypermagnesemia refers to an elevated magnesium level in the blood. It is usually the result of renal failure, excess magnesium replacement, or use of magnesium containing laxatives or antacids. Signs and symptoms of hypermagnesemia include bradycardia, weak and thready pulse, lethargy, tremors, hyporeflexia, muscle weakness, and cardiac arrest. Treatment for hypermagnesemia involves increasing fluid intake, discontinuing magnesium-containing medications, and in severe cases, hemodialysis or peritoneal dialysis. Additionally, administration of calcium gluconate can be helpful to reduce the cardiac effects of hypermagnesemia until the magnesium level can be lowered.Lewis, J. L., III. (April 2020). Hypermagnesemia. Merck Manual Professional Version. https://www.merckmanuals.com/professional/endocrine-and-metabolic-disorders/electrolyte-disorders/hypermagnesemia Hypomagnesemia refers to decreased magnesium level in the blood. It typically results from inadequate magnesium in the diet, or from loop diuretics that excrete magnesium. Patients with alcohol use disorder often have hypomagnesemia due to concurrent poor diet and impaired nutrient absorption that occurs with alcohol consumption. Chronic proton pump inhibitor use can also cause hypomagnesemia due to impaired nutrient absorption. Signs and symptoms of hypomagnesemia include nausea, vomiting, lethargy, weakness, leg cramps, tremor, dysrhythmias, and tetany that is associated with concurrent hypocalcemia that can occur with hypomagnesemia. Treatment for hypomagnesemia consists of increasing dietary intake of magnesium containing foods and oral or IV magnesium supplementation.Lewis, J. L., III. (April 2020). Hypomagnesemia. Merck Manual Professional Version. https://www.merckmanuals.com/professional/endocrine-and-metabolic-disorders/electrolyte-disorders/hypomagnesemia 7/7/20 See Table 15.4 for a comparison of causes, symptoms, and treatments of different electrolyte imbalances. As always, refer to agency lab reference ranges when providing patient care. Table 15.4 Comparison of Causes, Symptoms, and Treatments of Imbalanced Electrolyte Levels \| Elevated Level \| Decreased Level \| \| \|---\|---\|---\| \| Sodium (Na+) Normal range 136-145 mEq/L \| Hypernatremia Causes: Excessive salt intake Symptoms: Lethargy, irritability, seizures, and weakness Treatments: Rehydrate w/ D5W and increase water intake \| Hyponatremia Causes: Excessive water intake and diuretics Symptoms: Headache, confusion, coma Treatments: 3% NS and fluid restriction \| \| Potassium (K+) Normal range 3.5-5.1 mmol/L \| Hyperkalemia Causes: Kidney dysfunction, excessive potassium intake, and ACE inhibitors Symptoms: Cardiac arrhythmias, cramping, diarrhea, and irritability Treatments: Limit potassium in diet, loop diuretic, insulin, dialysis, and kayexalate \| Hypokalemia Causes: Loop and thiazide diuretics and IV administration of insulin Symptoms: Weakness, arrhythmias, lethargy, and thready pulse (WALT) Treatments: PO/IV potassium and increase K+ in diet \| \| Calcium (Ca++) Normal range 8.6 -10.2 mg/dL \| Hypercalcemia Causes: Overactive parathyroid glands and cancer Symptoms: Nausea, vomiting, constipation, and thirst Treatments: Decrease calcium in diet, increase mobility, and administer phosphorous \| Hypocalcemia Causes: Diuretic use and removal of parathyroid glands Symptoms: Numbness, tingling, Chvotek’s sign, and tetany Treatments: Increase Ca++ in diet and IV/PO calcium \| \| Magnesium (Mg+) Normal range 1.5-2.4 mg/dL \| Hypermagnesemia Causes: Kidney disease and excessive magnesium intake (i.e., laxatives and antacids) Symptoms: Muscle weakness, bradycardia, asystole, tremors, and slow reflexes Treatments: Dialysis, increased fluid intake, and stopping medications containing Mg+ \| Hypomagnesemia Causes: Diuretics, undernutrition, and long-term alcohol use disorder Treatments: Increase Mg+ in diet and PO/IV magnesium \| 15.5 Acid-Base Balance Open Resources for Nursing (Open RN) As with electrolytes, correct balance of acids and bases in the body is essential to proper body functioning. Even a slight variance outside of normal can be life-threatening, so it is important to understand normal acid-base values, as well their causes and how to correct them. The kidneys and lungs work together to correct slight imbalances as they occur. As a result, the kidneys compensate for shortcomings of the lungs, and the lungs compensate for shortcomings of the kidneys. Arterial Blood Gases Arterial blood gases (ABG) are measured by collecting blood from an artery, rather than a vein, and are most commonly collected via the radial artery. ABGs measure the pH level of the blood, the partial pressure of arterial oxygen (PaO2), the partial pressure of arterial carbon dioxide (PaCO2), the bicarbonate level (HCO3), and the oxygen saturation level (SaO2). Prior to collecting blood gases, it is important to ensure the patient has appropriate arterial blood flow to the hand. This is done by performing the Allen test. When performing the Allen test, pressure is held on both the radial and ulnar artery below the wrist. Pressure is released from the ulnar artery to check if blood flow is adequate. If arterial blood flow is adequate, warmth and color should return to the hand. pH pH is a scale from 0-14 used to determine the acidity or alkalinity of a substance. A neutral pH is 7, which is the same pH as water. Normally, the blood has a pH between 7.35 and 7.45. A blood pH of less than 7.35 is considered acidic, and a blood pH of more than 7.45 is considered alkaline. The pH of blood is a measure of hydrogen ion concentration. A low pH, less than 3.5, occurs in acidosis when the blood has a high hydrogen ion concentration. A high pH, greater than 7.45, occurs in alkalosis when the blood has a low hydrogen ion concentration. Hydrogen ions are by-products of the metabolism of substances such as proteins, fats, and carbohydrates. These by-products create extra hydrogen ions (H+) in the blood that need to be balanced and kept within normal range as described earlier. The body has several mechanisms for maintaining blood pH. The lungs are essential for maintaining pH and the kidneys also play a role. For example, when the pH is too low (i.e., during acidosis), the respiratory rate quickly increases to eliminate acid in the form of carbon dioxide (CO2). The kidneys excrete additional hydrogen ions (acid) in the urine and retain bicarbonate (base). Conversely, when the pH is too high (i.e., during alkalosis), the respiratory rate decreases to retain acid in the form of CO2. The kidneys excrete bicarbonate (base) in the urine and retain hydrogen ions (acid). PaCO2 PaCO2 is the partial pressure of arterial carbon dioxide in the blood. The normal PaCO2 level is 35-45 mmHg. CO2 forms an acid in the blood that is regulated by the lungs by changing the rate or depth of respirations. As the respiratory rate increases or becomes deeper, additional CO2 is removed causing decreased acid (H+) levels in the blood and increased pH (so the blood becomes more alkaline). As the respiratory rate decreases or becomes more shallow, less CO2 is removed causing increased acid (H+) levels in the blood and decreased pH (so the blood becomes more acidic). Generally, the lungs work quickly to regulate the PaCO2 levels and cause a quick change in the pH. Therefore, an acid-base problem caused by hypoventilation can be quickly corrected by increasing ventilation, and a problem caused by hyperventilation can be quickly corrected by decreasing ventilation. For example, if an anxious patient is hyperventilating, they may be asked to breathe into a paper bag to rebreathe some of the CO2 they are blowing off. Conversely, a postoperative patient who is experiencing hypoventilation due to the sedative effects of receiving morphine is asked to cough and deep breathe to blow off more CO2. HCO3 HCO3 is the bicarbonate level of the blood and the normal range is 22-26. HCO3 is a base managed by the kidneys and helps to make the blood more alkaline. The kidneys take longer than the lungs to adjust the acidity or alkalinity of the blood, and the response is not visible upon assessment. As the kidneys sense an alteration in pH, they begin to retain or excrete HCO3, depending on what is needed. If the pH becomes acidic, the kidneys retain HCO3 to increase the amount of bases present in the blood to increase the pH. Conversely, if the pH becomes alkalotic, the kidneys excrete more HCO3, causing the pH to decrease. PaO2 PaO2 is the partial pressure of arterial oxygen in the blood. It more accurately measures a patient’s oxygenation status than SaO2 (the measurement of hemoglobin saturation with oxygen). Therefore, ABG results are also used to manage patients in respiratory distress. See Table 15.5a for a review of ABG components, normal values, and key critical values. A critical ABG value means there is a greater risk of serious complications and even death if not corrected rapidly. For example, a pH of 7.10, a shift of only 0.25 below normal, is often fatal because this level of acidosis can cause cardiac or respiratory arrest or significant hyperkalemia.Mitchel, J. H., Wildenthal, K., & Johnson Jr., R. L. (1972). The effects of acid-base disturbances on cardiovascular and pulmonary function. Kidney International, 1, 375-389. https://www.kidney-international.org/article/S0085-2538(15)31047-4/pdf As you can see, failure to recognize ABG abnormalities can have serious consequences for your patients. Table 15.5a ABG Components, Descriptions, Adult Normal Values, and Critical ValuesWakeMed Pathology Laboratories. (2016). Critical values. https://www.wakemed.org/assets/documents/pathology/lab-critical-values.pdf \| ABG Component \| Description \| Adult Normal Value \| Critical Value \| \|---\|---\|---\|---\| \| pH \| \| 7.35-7.45 \| <7.25 >7.60 \| \| PaO2 \| \| 80-100 mmHg \| <60 mmHg \| \| PaCO2 \| \| 35-45 mmHg \| <25 mmHg >60 mmHg \| \| HCO3 \| \| 22-26 mEq/L \| <10 mEq/L >40 mEq/L \| \| SaO2 \| \| 95-100% \| <88% \| Video Review of Acid-Base BalanceForciea, B. (2017, May 10). Acid-base balance: Bicarbonate ion buffer. [Video]. YouTube. All rights reserved. Video used with permission. https://youtu.be/5_S5wZks9v8 Interpreting Arterial Blood Gases After the ABG results are received, it is important to understand how to interpret them. A variety of respiratory, metabolic, electrolyte, or circulatory problems can cause acid-base imbalances. Correct interpretation also helps the nurse and other health care providers determine the appropriate treatment and evaluate the effectiveness of interventions. Arterial blood gasses can be interpreted as one of four conditions: respiratory acidosis, respiratory alkalosis, metabolic acidosis, or metabolic alkalosis. Once this interpretation is made, conditions can further be classified as compensated, partially compensated, or uncompensated. A simple way to remember how to interpret ABGs is by using the ROME method of interpretation, which stands for Respiratory Opposite, Metabolic Equal. This means that the respiratory component (PaCO2) moves in the opposite direction of the pH if the respiratory system is causing the imbalance. If the metabolic system is causing the imbalance, the metabolic component (HCO3) moves in the same direction as the pH. Some nurses find the Tic-Tac-Toe method of interpretation helpful. If you would like to learn more about this method, click on the hyperlink below to view a video. Review of Tic-Tac-Toe Method of ABG InterpretationRegisteredNurseRN. (2015, May 6). ABGs made easy for nurses w/ tic tac toe method for arterial blood gas interpretation. [Video]. YouTube. All rights reserved. Video used with permission. https://youtu.be/URCS4t9aM5o Respiratory Acidosis Respiratory acidosis develops when carbon dioxide (CO2) builds up in the body (referred to as hypercapnia), causing the blood to become increasingly acidic. Respiratory acidosis is identified when reviewing ABGs and the pH level is below 7.35 and the PaCO2 level is above 45, indicating the cause of the acidosis is respiratory. Note that in respiratory acidosis, as the PaCO2 level increases, the pH level decreases. Respiratory acidosis is typically caused by a medical condition that decreases the exchange of oxygen and carbon dioxide at the alveolar level, such as an acute asthma exacerbation, chronic obstructive pulmonary disease (COPD), or an acute heart failure exacerbation causing pulmonary edema. It can also be caused by decreased ventilation from anesthesia, alcohol, or administration of medications such as opioids and sedatives. Chronic respiratory diseases, such as COPD, often cause chronic respiratory acidosis that is fully compensated by the kidneys retaining HCO3. Because the carbon dioxide levels build up over time, the body adapts to elevated PaCO2 levels so they are better tolerated. However, in acute respiratory acidosis, the body has not had time to adapt to elevated carbon dioxide levels, causing mental status changes associated with hypercapnia. Acute respiratory acidosis is caused by acute respiratory conditions, such as an asthma attack or heart failure exacerbation with pulmonary edema when the lungs suddenly are not able to ventilate adequately. As breathing slows and respirations become shallow, less CO2 is excreted by the lungs and PaCO2 levels quickly rise. Signs of symptoms of hypercapnia vary depending upon the level and rate of CO2 accumulation in arterial blood: - Patients with mild to moderate hypercapnia may be anxious and/or complain of mild dyspnea, daytime sluggishness, headaches, or hypersomnolence. - Patients with higher levels of CO2 or rapidly developing hypercapnia develop delirium, paranoia, depression, and confusion that can progress to seizures and coma as levels continue to rise. Individuals with normal lung function typically exhibit a depressed level of consciousness when the PaCO2 is greater than 75 to 80 mmHg, whereas patients with chronic hypercapnia may not develop symptoms until the PaCO2 rises above 90 to 100 mmHg.Feller-Kopman, D. J., & Schwartzstein, R. M. (2020). The evaluation, diagnosis, and treatment of the adult patient with acute hypercapnic respiratory failure. UpToDate. https://www.uptodate.com/contents/the-evaluation-diagnosis-and-treatment-of-the-adult-patient-with-acute-hypercapnic-respiratory-failure When a patient demonstrates signs of potential hypercapnia, the nurse should assess airway, breathing, and circulation. Urgent assistance should be sought, especially if the patient is in respiratory distress. The provider will order an ABG and prescribe treatments based on assessment findings and potential causes. Treatment for respiratory acidosis typically involves improving ventilation and respiration by removing airway restrictions, reversing oversedation, administering nebulizer treatments, or increasing the rate and depth of respiration by using a BiPAP or CPAP devices. BiPAP and CPAP devices provide noninvasive positive pressure ventilation to increase the depth of respirations, remove carbon dioxide, and oxygenate the patient. If these noninvasive interventions are not successful, the patient is intubated and placed on mechanical ventilation.A.D.A.M. Medical Encyclopedia [Internet]. Atlanta (GA): A.D.A.M., Inc.; c1997-2021. Respiratory acidosis; [updated 2021, February 8]. https://medlineplus.gov/ency/article/000092.htm,Feller-Kopman, D. J., & Schwartzstein, R. M. (2020). The evaluation, diagnosis, and treatment of the adult patient with acute hypercapnic respiratory failure. UpToDate. https://www.uptodate.com/contents/the-evaluation-diagnosis-and-treatment-of-the-adult-patient-with-acute-hypercapnic-respiratory-failure Read more details about oxygenation equipment in “Oxygen Therapy” in Open RN Nursing Skills. Respiratory Alkalosis Respiratory alkalosis develops when the body removes too much carbon dioxide through respiration, resulting in increased pH and an alkalotic state. When reviewing ABGs, respiratory alkalosis is identified when pH levels are above 7.45 and the PaCO2 level is below 35. With respiratory alkalosis, notice that as the PaCO2 level decreases, the pH level increases. Respiratory alkalosis is caused by hyperventilation that can occur due to anxiety, panic attacks, pain, fear, head injuries, or mechanical ventilation. Overdoses of salicylates and other toxins can also cause respiratory alkalosis initially and then often progress to metabolic acidosis in later stages. Acute asthma exacerbations, pulmonary embolisms, or other respiratory disorders can initially cause respiratory alkalosis as the lungs breath faster in an attempt to increase oxygenation, which decreases the PaCO2. After a while, however, these hypoxic disorders cause respiratory acidosis as respiratory muscles tire, breathing slows, and CO2 builds up in the blood. Patients experiencing respiratory alkalosis often report feelings of shortness of breath, dizziness or light-headedness, chest pain or tightness, paresthesias, and palpitations as a result of decreased carbon dioxide levels.Schwartzstein, R. M., Richards, J., Edlow, J. A., & Roy-Byrne, P. P. (2020). Hyperventilation syndrome in adults. UpToDate. https://www.uptodate.com/contents/hyperventilation-syndrome-in-adults Respiratory alkalosis is not fatal, but it is important to recognize that underlying conditions such as an asthma exacerbation or pulmonary embolism can be life-threatening, so treatment of these underlying conditions is essential. As the pH level increases, the kidneys will attempt to compensate for the shortage of H+ ions by reabsorbing HCO3 before it can be excreted in the urine. This is a slow process, so additional treatment may be necessary. Treatment of respiratory alkalosis involves treating the underlying cause of the hyperventilation. Acute management of patients who are hyperventilating should focus on patient reassurance, an explanation of the symptoms the patient is experiencing, removal of any stressors, and initiation of breathing retraining. Breathing retraining attempts to focus the patient on abdominal (diaphragmatic) breathing. Read more about breathing retraining in the following box. Breathing Retraining While sitting or lying supine, the patient should place one hand on their abdomen and the other on the chest, and then be asked to observe which hand moves with greater excursion. In hyperventilating patients, this will almost always be the hand on the chest. Ask the patient to adjust their breathing so that the hand on the abdomen moves with greater excursion and the hand on the chest barely moves at all. Assure the patient that this is hard to learn and will take some practice to fully master. Ask the patient to breathe in slowly over four seconds, pause for a few seconds, and then breathe out over a period of eight seconds. After 5 to 10 such breathing cycles, the patient should begin to feel a sense of calmness with a reduction in anxiety and an improvement in hyperventilation. Symptoms should ideally resolve with continuation of this breathing exercise. If the breathing retraining technique is not successful in resolving a hyperventilation episode and severe symptoms persist, the patient may be prescribed a small dose of a short-acting benzodiazepine (e.g., lorazepam 0.5 to 1 mg orally or 0.5 to 1 mg intravenously). Current research indicates that instructing patients who are hyperventilating to rebreathe carbon dioxide (CO2) by breathing into a paper bag can cause significant hypoxemia with significant complications, so this intervention is no longer recommended. If rebreathing is used, oxygen saturation levels should be continuously monitored.Schwartzstein, R. M., Richards, J., Edlow, J. A., & Roy-Byrne, P. P. (2020). Hyperventilation syndrome in adults. UpToDate. https://www.uptodate.com/contents/hyperventilation-syndrome-in-adults Metabolic Acidosis Metabolic acidosis occurs when there is an accumulation of acids (hydrogen ions) and not enough bases (HCO3) in the body. Under normal conditions, the kidneys work to excrete acids through urine and neutralize excess acids by increasing bicarbonate (HCO3) reabsorption from the urine to maintain a normal pH. When the kidneys are not able to perform this buffering function to the level required to excrete and neutralize the excess acid, metabolic acidosis results. Metabolic acidosis is characterized by a pH level below 7.35 and an HCO3 level below 22 when reviewing ABGs. It is important to notice that both the pH and HCO3 decrease with metabolic acidosis (i.e., the pH and HCO3 move in the same downward direction). A common cause of metabolic acidosis is diabetic ketoacidosis, where acids called ketones build up in the blood when blood sugar is extremely elevated. Another common cause of metabolic acidosis in hospitalized patients is lactic acidosis, which can be caused by impaired tissue oxygenation. Metabolic acidosis can also be caused by increased loss of bicarbonate due to severe diarrhea or from renal disease that causes decreased acid elimination. Additionally, toxins such as salicylate excess can cause metabolic acidosis.Emmett, M., & Szerlip, H. (2020). Approach to the adult with metabolic acidosis. UpToDate. https://www.uptodate.com/contents/approach-to-the-adult-with-metabolic-acidosis Nurses may first suspect that a patient has metabolic acidosis due to rapid breathing that occurs as the lungs try to remove excess CO2 in an attempt to resolve the acidosis. Other symptoms of metabolic acidosis include confusion, decreased level of consciousness, hypotension, and electrolyte disturbances that can progress to circulatory collapse and death if not treated promptly. It is important to quickly notify the provider of suspected metabolic acidosis so that an ABG can be drawn and treatment prescribed (based on the cause of the metabolic acidosis) to allow acid levels to improve. Treatment includes IV fluids to improve hydration status, glucose management, and circulatory support. When pH drops below 7.1, IV sodium bicarbonate is often prescribed to help neutralize the acids in the blood.A.D.A.M. Medical Encyclopedia [Internet]. Atlanta (GA): A.D.A.M., Inc.; c1997-2021. Metabolic acidosis; [updated 2021, February 8]. https://medlineplus.gov/ency/article/000335.htm,Emmett, M., & Szerlip, H. (2020). Approach to the adult with metabolic acidosis. UpToDate. https://www.uptodate.com/contents/approach-to-the-adult-with-metabolic-acidosis Metabolic Alkalosis Metabolic alkalosis occurs when there is too much bicarbonate (HCO3) in the body or an excessive loss of acid (H+ ions). Metabolic alkalosis is defined by a pH above 7.45 and an HCO3 level above 26 on ABG results. Note that both pH and HCO3 are elevated in metabolic alkalosis. Metabolic alkalosis can be caused by gastrointestinal loss of hydrogen ions, excessive urine loss, excessive levels of bicarbonate, or a shift of hydrogen ions from the bloodstream into cells. Prolonged vomiting or nasogastric suctioning can also cause metabolic alkalosis. Gastric secretions have high levels of hydrogen ions (H+), so as acid is lost, the pH level of the bloodstream increases. Excessive urinary loss (due to diuretics or excessive mineralocorticoids) can cause metabolic alkalosis due to loss of hydrogen ions in the urine. Intravenous administration of sodium bicarbonate can also cause metabolic alkalosis due to increased levels of bases introduced into the body. Although it was once thought that excessive intake of calcium antacids could cause metabolic alkalosis, it has been found that this only occurs if they are administered concurrently with Kayexelate.Emmett, M., & Szerlip, H. (2020). Causes of metabolic alkalosis. UpToDate. https://www.uptodate.com/contents/causes-of-metabolic-alkalosis Hydrogen ions may shift into cells due to hypokalemia, causing metabolic alkalosis. When hypokalemia occurs (i.e., low levels of potassium in the bloodstream), potassium shifts out of cells and into the bloodstream in an attempt to maintain a normal level of serum potassium for optimal cardiac function. However, as the potassium (K+) molecules move out of the cells, hydrogen (H+) ions then move into the cells from the bloodstream to maintain electrical neutrality. This transfer of ions causes the pH in the bloodstream to drop, causing metabolic alkalosis.Emmett, M., & Szerlip, H. (2020). Causes of metabolic alkalosis. UpToDate. https://www.uptodate.com/contents/causes-of-metabolic-alkalosis A nurse may first suspect that a patient has metabolic alkalosis due to a decreased respiratory rate (as the lungs try to retain additional CO2 to increase the acidity of the blood and resolve the alkalosis). The patient may also be confused due to the altered pH level. The nurse should report signs of suspected metabolic alkalosis because uncorrected metabolic alkalosis can result in hypotension and cardiac dysfunction.This work is a derivative of StatPearls by Brinkman and Sharma and is licensed under CC BY 4.0 Treatment is prescribed based on the ABG results and the suspected cause. For example, treat the cause of the vomiting, stop the gastrointestinal suctioning, or stop the administration of diuretics. If hypokalemia is present, it should be treated. If bicarbonate is being administered, it should be stopped. Patients with kidney disease may require dialysis.Emmett, M., & Szerlip, H. (2020). Causes of metabolic alkalosis. UpToDate. https://www.uptodate.com/contents/causes-of-metabolic-alkalosis Analyzing ABG Results Now that we’ve discussed the differences between the various acid-base imbalances, let’s review the steps to systematically interpret ABG results. Table 15.5b outlines the steps of ABG interpretation. Table 15.5b Analyzing ABG ResultsThis work is a derivative of StatPearls by Castro and Keenaghan and is licensed under CC BY 4.0,Woodruff, D. W. (2012). 6 easy steps to ABG analysis. Ed4Nurses, Inc. http://www.profcaseyscudmorern.org/uploads/4/5/0/4/45049193/abgebook.pdf \| Step \| Action \| \|---\|---\| \| Step 1: pH (normal 7.35-7.45) \| If pH is out of range, determine if it is acidosis or alkalosis: \| \| Step 2: PaCO2 (normal 35-45 mmHg) \| *If the imbalance does not appear to be caused by a respiratory problem, move on to evaluate the HCO3. \| \| Step 3: HCO3 (normal 22-26) \| \| \| Step 4: Determine level of compensation \| After determining the cause of the pH imbalance, determine if compensation is occurring. \| 15.6 Applying the Nursing Process Open Resources for Nursing (Open RN) The nursing process is used continuously when caring for individuals who have fluid, electrolyte, or acid-base imbalances, or at risk for developing them, because their condition can change rapidly. This systematic approach to nursing care ensures that subtle cues or changes are not overlooked and that appropriate outcomes and interventions are implemented according to the patient’s current condition. Assessment A thorough assessment provides valuable information about a patient’s current fluid, electrolyte, and acid-base balance, as well as risk factors for developing imbalances. Performing a chart review or focused health history is a good place to start collecting data, with any identified gaps or discrepancies verified during the physical assessment. It is also important to consider pertinent life span or cultural considerations that impact a patient’s fluid and electrolyte status. Subjective Assessment Subjective assessment data is information obtained from the patient as a primary source or family members or friends as a secondary source. This information must be obtained by interviewing the patient or someone accompanying the patient. Some of this information can be obtained through a chart review, but should be verified with the patient or family member for accuracy. Subjective data to obtain includes age; history of chronic disease, surgeries, or traumas; dietary intake; activity level; prescribed medications and compliance with taking medications; pain; and bowel and bladder functioning. Subjective assessment data is helpful to determine normal pattern identification and risk identification. For example, a history of kidney disease or heart failure places the patient at risk for fluid volume excess, whereas diuretic use places the patient at risk for fluid volume deficit and electrolyte and acid-base imbalances. A history of diabetes mellitus also places a patient at risk for fluid, electrolyte, and acid-base imbalances. Recognizing these risks helps nurses be prepared for complications that may arise and allows the nurse to recognize subtle cues as problems develop. Objective Assessment Objective assessment data is information that the nurse directly observes. This data is obtained through a physical examination using inspection, auscultation, and palpation. A complete head-to-toe assessment should be performed to avoid missing clues to the patient’s condition. Focused assessments such as trends in weight, 24-hour intake and output, vital signs, pulses, lung sounds, skin, and mental status are used to determine fluid balance, electrolyte, and acid-base status. - Accurate daily weights can provide important clues to fluid balance. Weights must be taken on the same scale, at the same time of day, with the patient wearing similar clothing in order to be accurate. A one kilogram change in weight in 24 hours is considered significant because this represents a one liter fluid gain or loss and should be reported to the provider. - Accurate measurement of 24-hour intake and output helps validate weight findings. Averaged urine output of less than 30 mL/hour or 0.5mL/hr/kg of concentrated urine should be reported to the provider. - Vital signs should be analyzed. An elevated blood pressure and bounding pulses are often seen with fluid volume excess. Decreased blood pressure with an elevated heart rate and a weak or thready pulse are hallmark signs of fluid volume deficit. Systolic blood pressure less than 100 mm Hg in adults, unless other parameters are provided, should be reported to the health care provider. - Lung crackles can signify fluid volume excess and are often first auscultated in the lower posterior lung fields. - Tight, edematous, shiny skin indicates fluid volume excess. See Figure 15.15“Combinpedal.jpg” by James Heilman, MD is licensed under CC BY-SA 3.0 for an image of edema. Conversely, skin tenting, dry mucous membranes, or dry skin indicate fluid volume deficit. - New mental status changes such as confusion or decreased level of consciousness can indicate fluid, electrolyte, or acid-base imbalance, especially hypo- or hypernatremia, acid-base imbalances, or fluid volume deficit. - Cardiac arrhythmias can be seen with acid-base imbalances and electrolyte imbalances, especially with hypo- or hyperkalemia and alkalosis. See Table 15.6a for a comparison of expected and unexpected findings and those that require notification of a health care provider. Table 15.6a Expected Findings Versus Unexpected Findings Indicating a Fluid ImbalanceEl-Sharkawy, A. M., Sahota, O., Maughan, R. J., & Lobo, D. N. (2014). The pathophysiology of fluid and electrolyte balance in the older adult surgical patient. Clinical Nutrition, 33(1), 6-13. https://doi.org/10.1016/j.clnu.2013.11.010 \| Assessment \| Expected Findings \| Unexpected Findings Indicating Excessive Fluid Volume Bolded items are critical conditions that require immediate health care provider notification. \| Unexpected Findings Indicating Deficient Fluid Volume \| \|---\|---\|---\|---\| \| Vital signs \| Blood pressure, heart rate, and oxygen saturation levels within normal limits \| Elevated blood pressure, increased respiratory rate, or decreased oxygen saturation \| Decreased blood pressure or elevated heart rate \| \| Neurological \| Alert and oriented \| Headache \| Headache, confusion, decreased level of consciousness, dizziness, or weakness \| \| Cardiac \| Normal heart rate and rhythm, capillary refill <3 seconds, and normal pulses \| Bounding pulses, S3 heart sound, or jugular venous distention \| Weak, thready pulses; sluggish capillary refill; or chest pain \| \| Respiratory \| Clear lung sounds throughout, normal respiratory rate, and no shortness of breath \| Crackles in lung fields, pink frothy sputum, shortness of breath, or respiratory distress \| Shortness of breath possible \| \| Gastrointestinal \| Bowel sounds present x4 quadrants and normal stool consistency and frequency for patient \| Constipation with dry, hard stools \| \| \| Urinary \| Clear urine, normal urine specific gravity, and urine output greater than 30 ml/hr \| Decreased urine output <30 mL/hr or < 0.5 mL/kg/hr concentrated urine \| Decreased urine output <30 mL/hr or <0.5 mL/kg/hr concentrated urine, or elevated urine specific gravity \| \| Integumentary \| Normal skin turgor and moist mucous membranes \| Tight, edematous, or shiny skin \| Tenting (poor skin turgor); dry, sticky mucous membranes; or dry skin \| \| Weight \| <1kg change in weight over 24 hours \| >1kg increase over 24 hours \| >1kg decrease over 24 hours \| Diagnostic and Lab Work Diagnostic tests and lab work provide important information about fluid status, electrolyte, and acid-base balance and should be used in conjunction with a thorough subjective and objective assessment to form a complete picture of the patient’s overall status. It is important to cluster diagnostic and lab assessment data with subjective and objective assessment data to ensure a complete assessment picture. This will help ensure correct information is reported to the provider as necessary. Lab work provides important clues to overall fluid status. Common lab tests used to evaluate fluid status include serum osmolarity, urine specific gravity, hematocrit, and blood urea nitrogen (BUN). Serum osmolarity (often interchanged with the term serum osmolality) measures the concentration of particles in the blood with a normal range of 275 to 295 mmol/kg). Normal value ranges may vary slightly among different laboratories. In healthy people, when serum osmolality in the blood becomes high, the body releases antidiuretic hormone (ADH). This hormone causes the kidneys to reabsorb water, resulting in dilution of the blood and the return of serum osmolarity to normal range. An elevated serum osmolarity level means the blood is more concentrated than normal and often indicates deficient fluid volume deficit. A decreased serum osmolarity means the blood is more dilute than normal and may indicate a fluid volume excess.A.D.A.M. Medical Encyclopedia [Internet]. Atlanta (GA): A.D.A.M., Inc.; c1997-2021. Osmolality blood test; [updated 2021, February 8]. https://medlineplus.gov/ency/article/003463.htm Urine osmolarity measures the concentration of particles in the urine. An increased urine osmolarity result means the urine is concentrated and can indicate fluid volume deficit. A decreased urine osmolarity result means the urine is dilute and can indicate excess fluid intake.RnCeus.com. (n.d.). Serum and urine osmolality. https://www.rnceus.com/renal/renalosmo.html Urine specific gravity is a urine test that commonly measures hydration status by measuring the concentration of particles in urine. Normal urine specific gravity levels are between 1.010 and 1.020. A urine specific gravity above 1.020 indicates concentrated urine and can indicate a fluid volume deficit, similarly to an elevated urine osmolarity. A urine specific gravity below 1.010 indicates dilute urine, which can occur with excessive fluid intake.Flasar, C. (2008). What is urine specific gravity? Nursing2008, 38(7), 14. https://doi.org/10.1097/01.nurse.0000325315.41513.a0. When a condition called “Excessive Fluid Volume” occurs, altered physiological mechanisms impact the kidney’s ability to increase urine output to eliminate excessive fluid volume, causing urine output to decrease. As a result, the serum osmolarity decreases as fluid is retained but the urine specific gravity is elevated because urine is concentrated. It is often part of a complete blood count (CBC), a routine test that measures different components of your blood. The normal hematocrit for men is 42 to 52%; for women it is 37 to 47%, but these ranges may vary slightly across labs. In addition to measuring red blood cells, hematocrit levels can also be used to evaluate fluid balance. When deficient fluid volume is occurring, the plasma component of the blood also decreases, causing an elevated concentration of red blood cells (and an elevated hematocrit). In this case, drinking more fluid or receiving intravenous fluids will bring the hematocrit level back to normal range. Conversely, if a patient is experiencing “Excessive Fluid Volume,” the plasma component of the blood is increased, causing dilution of the red blood cells and a decreased hematocrit level.MedlinePlus [Internet]. Bethesda (MD): National Library of Medicine (US); Hematocrit test; [updated 2020, Jul 31; reviewed 2020, Jul 31; cited 2021, Feb 11]. https://medlineplus.gov/lab-tests/hematocrit-test/,Billett, H. H. (1990). Hemoglobin and hematocrit. In Walker H. K., Hall W. D., Hurst J. W. (Eds.), Clinical methods: The history, physical, and laboratory examinations (3rd ed.). Butterworths. https://www.ncbi.nlm.nih.gov/books/NBK259/ See Figure 15.16“1901_Composition_of_Blood.jpg” by Arabic is licensed under CC BY 3.0 for an illustration of normal hematocrit, elevated hematocrit, and decreased hematocrit due to fluid imbalance. Blood Urea Nitrogen (BUN) measures the amount of urea nitrogen in your blood. BUN and serum creatinine levels are used to evaluate kidney function, with increased levels indicating worsening kidney function. In general, the normal BUN range is 7 to 20 mg/dL, but normal ranges vary depending on the reference range used by the lab and the patient’s age. Patients with “Deficient Fluid Volume” can also have elevated BUN levels for the same reason that hematocrit is affected; as plasma levels decrease, the blood becomes more concentrated. In addition to monitoring lab work for results indicating fluid imbalance, electrolytes, specifically sodium, potassium, calcium, phosphorus, and magnesium, should be monitored closely for patients at risk. Refer to Table 15.4 in the “Electrolytes” section for an overview of electrolyte imbalances, common symptoms, and common treatments. Additional diagnostic tests used to evaluate for signs of fluid and electrolyte imbalances are the chest X-ray and the electrocardiogram. A chest X-ray evaluates for fluid in the lungs, a common complication of excessive fluid volume. An electrocardiogram (ECG) evaluates for cardiac complications resulting from electrolyte imbalances. Arterial blood gases are used to closely monitor critically ill patients, such as patients in diabetic ketoacidosis or in severe respiratory distress. ABG results provide important clues about respiratory status, oxygenation, and metabolic processes occurring in the body. See Table 15.6b for a summary of laboratory findings associated with fluid, electrolyte, and acid-base imbalances. Table 15.6b Lab Values Associated with Fluid and Electrolyte Imbalances \| Lab Value \| Normal Ranges \| \|---\|---\| \| Serum osmolarity \| 275 to 295 mmol/kg \| \| Urine Specific Gravity \| 1.010 and 1.020 \| \| Hematocrit \| Men: 42 to 52% Women: 37 to 47% \| \| BUN \| 7 to 20 mg/dL \| \| Serum sodium \| 135-150 mEq/L \| \| Serum potassium \| 3.5-5 mEq/L \| \| Serum magnesium \| 1.5-2.4 mEq/L \| \| Serum calcium \| 8.5-10.3 mg/dL \| \| Serum phosphorus \| 2.5-4 mg/dL \| \| ABG \| pH: 7.35 and 7.45 PaO2: 80-100 mm Hg HCO3: 22-26 mEq/L PaO2: 35-45 mm Hg \| Life Span Considerations There are several life span considerations when assessing for fluid, electrolyte, and acid-base balance. Newborns and Infants Newborns and infants have a large proportion of water weight compared to adults, with approximately 75% of weight being water. During the first week after birth, extracellular fluid is lost in urine along with sodium. Additionally, compensatory mechanisms such as the Renin-Angiotensin-Aldosterone System are less developed, and newborn kidneys are less able to concentrate urine, resulting in a decreased ability to retain sodium. Newborns and infants also have a greater body surface area, making them more susceptible to insensible fluid losses through the skin and lungs via evaporation. This causes increased risk of developing hyponatremia and fluid volume deficit. In contrast, newborns are less able to excrete potassium, placing them at risk for hyperkalemia.Ringer, S. (2020). Fluid and electrolyte therapy in newborns. UpToDate. https://www.uptodate.com/contents/fluid-and-electrolyte-therapy-in-newborns Episodes of vomiting and diarrhea also place infants at an increased risk of quickly developing fluid and electrolyte disturbances. When monitoring urine output in infants, parents are often asked about the number of wet diapers in a day. Nurses may also weigh diapers for hospitalized infants for more accurate measurement of urine output. Children and Adolescents Children and adolescents are at risk for dehydration when physically active in hot environments causing excessive sweating. Illnesses causing diarrhea, vomiting, or fever can also quickly cause fluid deficit if there is little fluid intake to replace the water and sodium lost. For this reason, it is important to educate parents regarding the importance of fluid intake when their child is sweating or ill.Iglesia, I., Guelinckx, I., De Miguel-Etayo, P. M., González-Gil, E. M., Salas-Salvadó, J., Kavouras, S. A., Gandy, J., Martínez, H., Bardosono, S., Abdollahi, M., Nasseri, E., Jarosz, A., Ma, G., Carmuega, E., Thiébaut, I., & Moreno, L. A. (2015). Total fluid intake of children and adolescents: cross-sectional surveys in 13 countries worldwide. European Journal of Nutrition, 54, 57–67. https://doi.org/10.1007/s00394-015-0946-6 Older Adults Older adults are at risk for fluid and electrolyte imbalances for a variety of reasons, including surgery, chronic diseases such as heart and kidney disease, diuretic use, and decreased mobility that limits the ability to obtain hydration. They also have a decreased thirst reflex, which contributes to decreased fluid consumption. Kidney function naturally decreases with age, resulting in decreased sodium and water retention, as well as decreased potassium excretion. These factors place older patients at risk for fluid volume deficit and electrolyte abnormalities.El-Sharkawy, A. M., Sahota, O., Maughan, R. J., & Lobo, D. N. (2014). The pathophysiology of fluid and electrolyte balance in the older adult surgical patient. Clinical Nutrition, 33(1), 6-13. https://doi.org/10.1016/j.clnu.2013.11.010 Diagnoses There are many nursing diagnoses applicable to fluid, electrolyte, and acid-base imbalances. Review a nursing care planning resource for current NANDA-I approved nursing diagnoses, related factors, and defining characteristics. See Table 15.6c for commonly used NANDA-I diagnoses associated with patients with fluid and electrolyte imbalances.Herdman, T., & Kamitsuru, S. (2017). NANDA international nursing diagnoses: Definitions & classification 2018-2020 (11th ed.). Thieme Publishers. pp. 182-186. Table 15.6c Common NANDA-I Nursing Diagnoses Related to Fluid and Electrolyte ImbalancesHerdman, T., & Kamitsuru, S. (2017). NANDA international nursing diagnoses: Definitions & classification 2018-2020 (11th ed.). Thieme Publishers. pp. 182-186. \| NANDA-I Diagnosis \| Definition \| Defining Characteristics \| \|---\|---\|---\| \| Excess Fluid Volume \| Surplus intake and/or retention of fluid. \| Adventitious breath sounds Elevated blood pressure Altered mental status Anxiety Decreased hematocrit, serum osmolarity, and BUN Dyspnea Edema Fluid intake exceeds output Jugular vein distension Restlessness Weight gain >1 kg/24 hours \| \| Deficient Fluid Volume \| Decreased intravascular, interstitial, and/or intracellular fluid. This refers to dehydration, water loss alone without change in sodium. \| Altered mental status Decreased skin turgor Decreased blood pressure Decreased urine output Dry skin and mucous membranes Increased heart rate Increased serum osmolarity, hematocrit, and BUN Increased urine concentration Sudden weight loss Thirst Weakness \| \| Risk for Imbalanced Fluid Volume \| Susceptible to a decrease, increase, or rapid shift from one to the other of intravascular, interstitial, and/or intracellular fluid, which may compromise health. This refers to body fluid loss, gain, or both. \| Diarrhea Vomiting Excessive fluid volume Insufficient fluid volume \| \| Risk for Electrolyte Imbalance \| Susceptible to changes in serum electrolyte levels, which may compromise health. \| Diarrhea Vomiting Excessive fluid volume Insufficient fluid volume \| Excess Fluid Volume Example A patient with heart failure has been hospitalized with an acute exacerbation with dyspnea and increased edema in the lower extremities. A sample PES statement is, “Fluid Volume Excess related to a compromised regulatory mechanism as evidenced by edema, crackles in lower posterior lungs, and weight gain of 2 kg in 24 hours.” Deficient Fluid Volume Example An elderly patient develops severe diarrhea due to food poisoning and is admitted to the hospital with dehydration. A sample PES statement is, “Deficient Fluid Volume related to insufficient fluid intake as evidenced by blood pressure 90/60, dry mucous membranes, decreased urine output, and an increase in hematocrit.” Risk for Imbalanced Fluid Volume Example A patient who is ten weeks pregnant has developed severe vomiting due to severe morning sickness. A sample PES statement is, “Risk for Imbalanced Fluid Volume as evidenced by vomiting.” The nurse plans to educate the patient about tips to stay hydrated despite vomiting, as well as when to contact the provider if signs of dehydration develop. Risk for Electrolyte Imbalance Example A patient with chronic kidney disease is prescribed a diuretic to control fluid retention. A sample PES statement is, “Risk for Electrolyte Imbalance as evidenced by insufficient knowledge of modifiable factors.” The nurse plans to educate the patient about signs and symptoms of fluid and electrolyte imbalance and when to contact the provider. Note: Recall that risk diagnoses do not contain related factors in PES statements because a vulnerability for a potential problem is being identified for the patient. Instead, the phrase “as evidenced by” is used to refer to the evidence of risk that exists. Read more about formulating PES statements in the “Nursing Process” chapter. Outcome Identification Goals for a patient experiencing fluid, electrolyte, or acid-base imbalances depend on the chosen nursing diagnosis and specific patient situation. Typically, goals should relate to resolution of the imbalance. For example, if the nursing diagnosis is Excess Fluid Volume, then an appropriate goal would pertain to resolution of the fluid volume excess. Remember that goals are broad and outcomes should be narrowly focused and written in SMART format (Specific, Measurable, Achievable, Realistic, and Time Oriented). For the nursing diagnosis of Excess Fluid Volume, an overall goal is, “Patient will achieve fluid balance.” Fluid balance for a patient with Excess Fluid Volume is indicated by body weight returning to baseline with no peripheral edema, neck vein distention, or adventitious breath sounds.Ackley, B., Ladwig, G., Makic, M. B., Martinez-Kratz, M., & Zanotti, M. (2020). Nursing diagnosis handbook: An evidence-based guide to planning care (12th ed.). Elsevier. pp. 360-363, 406-416. An example of a SMART outcome is, “The patient will maintain clear lung sounds with no evidence of dyspnea over the next 24 hours.” For patients experiencing Electrolyte Imbalances, an appropriate goal is, “Patient will maintain serum sodium, potassium, calcium, phosphorus, magnesium, and/or pH levels within normal range.” An additional goal is, “The patient will maintain a normal sinus heart rhythm with regular rate,” because many electrolyte imbalances impact the electrical conduction system of the heart and this is a life-threatening complication. Planning Interventions Evidence-based interventions should be planned according to the patient’s history and specific fluid, electrolyte, or acid-base imbalance present. Refer to a nursing care planning resource for evidence-based interventions for specific nursing diagnoses. Table 15.6d lists selected interventions for key imbalances.Ackley, B., Ladwig, G., Makic, M. B., Martinez-Kratz, M., & Zanotti, M. (2020). Nursing diagnosis handbook: An evidence-based guide to planning care (12th ed.). Elsevier. pp. 360-363, 406-416.,Fluid overload. (2021). Lippincott advisor. http://advisor.lww.com,Dehydration. (2021). Lippincott advisor. http://advisor.lww.com,Electrolyte imbalance. (2021). Lippincott advisor. http://advisor.lww.com Table 15.6d Interventions for Imbalances \| Nursing Diagnosis \| Interventions \| \|---\|---\| \| Excessive Fluid Volume \| \| \| Deficient Fluid Volume \| \| \| Risk for Electrolyte Imbalance \| \| Read more about medications affecting fluid and electrolyte balance, such as diuretics, in the “Cardiovascular and Renal System” chapter in Open RN Nursing Pharmacology. Read about intravenous fluids used to treat Fluid Volume Deficit in the “IV Therapy Management” chapter in Open RN Nursing Skills. Implement Interventions Safely Patients with fluid and electrolyte imbalances can quickly move from one imbalance to another based on treatments received. It is vital to reassess a patient before implementing interventions to ensure current status warrants the prescribed intervention. For example, a patient admitted with Fluid Volume Deficit received intravenous fluids (IV) over the past 24 hours. When the nurse prepares to administer the next bag of IV fluids, she notices the patient has developed pitting edema in his lower extremities. She listens to his lungs and discovers crackles. The nurse notifies the prescribing provider, and the order for intravenous fluids is discontinued and a new order for diuretic medication is received. Therefore, assessments for new or worsening imbalances should be performed prior to implementing interventions:Ackley, B., Ladwig, G., Makic, M. B., Martinez-Kratz, M., & Zanotti, M. (2020). Nursing diagnosis handbook: An evidence-based guide to planning care (12th ed.). Elsevier. pp. 360-363, 406-416. - Monitor daily weights for sudden changes. A weight change of greater than 1 kg in 24 hours (using the same scale and type of clothing) should be reported to the provider. - Monitor location and extent of edema using the 1+ to 4+ scale to quantify edema. - Monitor intake and output over a 24-hour period; note trends of decreasing urine output in relation to fluid intake indicating potential development of Fluid Volume Excess. - Monitor lab work such as serum osmolarity, serum sodium, BUN, and hematocrit for abnormalities. (For example, a patient receiving IV fluids may develop Fluid Volume Excess, resulting in decreased levels of serum osmolarity, serum sodium, BUN, and hematocrit. Conversely, a patient receiving IV diuretics can quickly become dehydrated, resulting in elevated levels of serum osmolarity, serum sodium, BUN, and hematocrit.) - For patients receiving intravenous fluids, monitor for the development of excessive fluid volume. Monitor lung sounds for crackles and ask about the presence of dyspnea. Report new abnormal findings to the provider. - For patients receiving diuretic therapy, monitor for fluid volume deficit and electrolyte imbalances such as hypokalemia and hyponatremia. Implement fall precautions for patients with orthostatic hypotension, restlessness, anxiety, or confusion related to fluid imbalances. Evaluation The effectiveness of interventions implemented to maintain fluid balance must be continuously evaluated. Evaluation helps the nurse determine whether goals and outcomes are met and if interventions are still appropriate for the patient. If outcomes and goals are met, the plan of care can likely be discontinued. If outcomes and goals are not met, they may need to be revised. It is also possible that interventions may need to be added or revised to help the patient meet their goals and outcomes. Table 15.6e provides a list of assessment findings indicating imbalances are improved. Table 15.6e Evaluating for Improvement of Imbalances \| Imbalance \| Signs and Symptoms of Improvement \| \|---\|---\| \| Fluid Volume Excess \| Decreased crackles, decreased edema, decreased shortness of breath, and/or improved jugular venous distention \| \| Fluid Volume Deficit \| Increased blood pressure, decreased heart rate, normal skin turgor, and/or moist mucous membranes \| \| Electrolyte Imbalances \| Electrolyte levels return to normal and/or absence of signs or symptoms of deficit or excess \| \| Acid-Base Imbalance \| ABGs return to normal or baseline, resolution of vomiting or diarrhea, and/or no respiratory distress \| 15.7 Putting It All Together Patient Scenario Mr. Hernandez is a 54-year-old patient admitted to the medical telemetry floor with a diagnosis of heart failure exacerbation. He tells the nurse, “My breathing has gotten worse the past last three days and I have a lot of swelling in my feet.” Applying the Nursing Process Assessment: Vital signs at the start of shift were blood pressure 154/94, heart rate 88, respiratory rate 24, and oxygen saturation 88%. On assessment, the nurse finds fine crackles in bilateral posterior lower lung bases, an S3 heart sound, and 2+ pitting edema in bilateral lower extremities midway to the knee. The nurse reviews the patient’s chart and discovers Mr. Hernandez has gained 10 pounds since his previous office visit last week. Based on the assessment information that has been gathered, the nurse creates the following nursing care plan for Mr. Hernandez: Nursing Diagnosis: Excess Fluid Volume related to compromised regulatory mechanism as evidenced by fine crackles in bilateral posterior lung bases, S3 heart sound, weight gain of 10 pounds in the past week, and the patient states, “My breathing has gotten worse the past last three days and I have a lot of swelling in my feet.” Overall Goal: The patient will demonstrate stabilization in fluid volume. SMART Expected Outcomes: - Mr. Hernandez’s vital signs and weight will return to his baseline in the next 48 hours. - Mr. Hernandez will verbalize three rules of dietary and fluid restriction to follow at home following his educational session. Planning and Implementing Nursing Interventions: The nurse will weigh the patient daily and analyze weight trends and 24-hour intake and output. The nurse will closely monitor lung sounds, respiratory rate, and oxygenation status. The nurse will establish a 24-hour schedule for fluid intake and educate the patient regarding fluid restriction. The nurse will closely monitor lab results, especially sodium and potassium, and monitor for symptoms of fluid shifts. The nurse will provide patient education regarding fluid and sodium restrictions. Sample Documentation: The patient was admitted with acute heart failure exacerbation and stated, “My breathing has gotten worse the past last three days and I have a lot of swelling in my feet.” On admission to the unit at 0900, vital signs were blood pressure 154/94, heart rate 88, respiratory rate 24, and oxygen saturation 88%. Fine crackles were present in bilateral posterior lower lung bases, an S3 heart sound was present, and there was 2+ pitting edema in bilateral lower extremities midway to the knee. The chart indicates he has gained 10 pounds since his previous office visit last week. Provider orders and fluid restrictions were implemented. Lab results are within normal ranges. Patient education regarding fluid and sodium restrictions and a handout were provided. At the end of the session, Mr. Hernandez was able to report back three rules of dietary and fluid restrictions to follow at home when discharged. Evaluation: By the end of the shift, the second SMART outcome was “met” when Mr. Hernandez was able to report back three rules of dietary and fluid restrictions after the patient education session. The first SMART outcome was not yet met but will be reevaluated every shift for the next 24 hours. 15.8 Learning Activities Open Resources for Nursing (Open RN) Learning Activities (Answers to “Learning Activities” can be found in the “Answer Key” at the end of the book. Answers to interactive activity elements will be provided within the element as immediate feedback.) Scenario A“HF-RTD.JPG“ by ARISE project is licensed under CC BY 4.0 Mr. Smith, a 60-year-old male, was admitted to the general medical floor with a diagnosis of an exacerbation of heart failure. See Figure 15.17 for an image of Mr. Smith.“HF-RTD.JPG“ by ARISE project is licensed under CC BY 4.0 He has a past medical history of hypertension and coronary artery disease. His admitting weight was 225 pounds. His baseline weight from a previous clinic visit was 210 pounds. On admission, he had fine crackles throughout his lower posterior lobes and 4+ pitting edema in his lower extremities. His ABG results on admission were: pH 7.30, PaCO2 50 mmHg, PaO2 80 mm Hg, HCO3- 21 mEq/L, SaO2 85%. Questions - Interpret Mr. Smith’s ABG results on admission. - Explain the likely cause of the ABG results. - Create a nursing diagnosis for Mr. Smith’s fluid status in PES format based on his admission data. Mr. Smith has received multiple doses of IV diuretics over the past three days since admission. During your morning assessment, Mr. Smith tells you he very thirsty and feels dizzy. You notice he is irritable and is becoming increasingly confused. You quickly obtain his vital signs: BP 85/45, HR 110, RR 24/minute, O2 saturation 98% on 2L/min per nasal cannula, and temperature 37.2 degrees Celsius. His lung sounds are clear and his heart sounds are regular sinus rhythm. You notice his weight this morning was 205 pounds. You call the provider and receive orders for STAT Basic Metabolic Panel and to initiate 0.9% Normal Saline IV fluids at 250 mL/hour until the provider arrives to evaluate the patient. The Basic Metabolic Panel results (with the lab’s normal reference range in parentheses) are: Sodium: 155 mEq/L (135-145) Potassium: 3.3 mEq/L (3.5-5.3) Chloride: 103 mEq/L (98-108) Carbon dioxide: 25 mEq/L (23-27) Blood urea nitrogen (BUN): 30 mg/dL (10-25) Creatinine: 1.9 mg/dL (0.5-1.5) Glucose: 100 mg/dL (fasting 70-99) Questions 4. What is Mr. Smith’s fluid balance this morning? Support your answer with data. 5. What is the probable cause of his fluid balance? 6. Interpret Mr. Smith’s lab results. What are the potential causes of these results? 7. Create a nursing diagnosis statement in PES format for Mr. Smith’s current fluid status. 8. Create a new expected outcome in SMART format for Mr. Smith. 9. In addition to providing intravenous fluids, what additional interventions will you implement for Mr. Smith? 10. How will you evaluate if the nursing interventions are effective? Scenario B“Hospitalized Male“ by ARISE project is licensed under CC BY 4.0 A 74-year-old male, Mr. M., was admitted to the general medical floor during the night shift with a diagnosis of pneumonia. See Figure 15.18 for an image of Mr. M.“Hospitalized Male“ by ARISE project is licensed under CC BY 4.0 He has a past medical history of alcohol abuse and coronary artery disease. You are the day shift nurse, and during your morning assessment you notice that Mr. M. becomes increasingly lethargic and is not following commands consistently. You obtain the following vital signs: BP 80/45, HR 110, RR 8 and labored, O2 saturation 80% on 3L per nasal cannula, temperature 38.1 degrees Celsius. His lung sounds reveal coarse crackles throughout, and you notice he is using accessory muscles with breathing. You notify the provider using an SBAR report and receive orders to increase oxygen to 10L per non-rebreather mask. Lab results are ordered with the following results: ABGs: pH 7.30, PaCO2 50, PaO2 59, HCO3 24, SaO2 80 Potassium: 5.9 mEq/L Magnesium: 1.0 mEq/L Calcium: 10.2 mg/dL Sodium: 137 mEq/L Hematocrit: 55% Serum Osmolarity: 305 mmol/kg BUN: 30 mg/dL Urine Specific Gravity: 1.025 Questions: - What is Mr. M.’s fluid balance? Provide data supporting the imbalance. - What is your interpretation of Mr. M.’s ABGs? - What is your interpretation of Mr. M.’s electrolyte studies? - Is Mr. M. stable or unstable? Why? - For what complications will you monitor? - Write an SBAR communication you would have with the health care provider to notify them about Mr. M.’s condition. - Create a NANDA-I diagnosis for Mr. M. in PES format. - Identify an expected outcome for Mr. M. in SMART format. - What interventions will you plan for Mr. M.? - How will you evaluate if your interventions are effective? - Write a nursing note about Mr. M.’s condition and your actions taken. This can be in the form of a DAR, SOAP, or summary nursing note. An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=1430#h5p-93 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=1430#h5p-31 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=1430#h5p-32 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=1430#h5p-86 XV Glossary Open Resources for Nursing (Open RN) Active transport: Movement of solutes and ions across a cell membrane against a concentration gradient from an area of lower concentration to an area of higher concentration using energy during the process. Chvostek’s sign: An assessment sign of acute hypocalcemia characterized by involuntary facial muscle twitching when the facial nerve is tapped. Diffusion: The movement of solute particles from an area of higher concentration to an area of lower concentration. Edema: Swelling caused by excessive interstitial fluid retention. Extracellular fluids (ECF): Fluids found outside cells in the intravascular or interstitial spaces. Filtration: Movement of fluids through a permeable membrane utilizing hydrostatic pressure. Hydrostatic pressure: The pressure that a contained fluid exerts on what is confining it. Hypercapnia: Elevated levels of retained carbon dioxide in the body. Hypertonic solution: Intravenous fluids with a higher concentration of dissolved particles than blood plasma. Hypervolemia: Excess intravascular fluid. Used interchangeably with “excessive fluid volume.” Hypotonic solution: Intravenous fluids with a lower concentration of dissolved particles than blood plasma. Hypovolemia: Intravascular fluid loss. Used interchangeably with “deficient fluid volume” and “dehydration.” Interstitial fluids: Fluids found between the cells and outside of the vascular system. Intracellular fluids (ICF): Fluids found inside cells consisting of protein, water, and electrolytes. Intravascular fluids: Fluids found in the vascular system consisting of the body’s arteries, veins, and capillary networks. Isotonic solution: Intravenous fluids with a similar concentration of dissolved particles as blood plasma. Oncotic pressure: Pressure inside the vascular compartment created by protein content of the blood (in the form of albumin) that holds water inside the blood vessels. Osmolality: Proportion of dissolved particles in a specific weight of fluid. Osmolarity: Proportion of dissolved particles or solutes in a specific volume of fluid. Osmosis: Movement of fluid through a semipermeable membrane from an area of lesser solute concentration to an area of greater solute concentration. Passive transport: Movement of fluids or solutes down a concentration gradient where no energy is used during the process. Renin-Angiotensin-Aldosterone System (RAAS): A body system that regulates extracellular fluids and blood pressure by regulating fluid output and electrolyte excretion. Trousseau’s sign: A sign associated with hypocalcemia that causes a spasm of the hand when a blood pressure cuff is inflated. Urine specific gravity: A measurement of hydration status that measures the concentration of particles in urine. Elimination XVI 16.1 Elimination Introduction Open Resources for Nursing (Open RN) Learning Objectives - Assess factors that put a patient at risk for alterations in urinary and bowel elimination - Identify factors related to alterations in elimination across the life span - Outline the data that must be collected for identification of alterations in bowel/urine elimination - Base decisions on the interpretation of basic diagnostic tests of urinary and bowel elimination: urinalysis and occult blood - Detail the nonpharmacologic measures to promote urinary and bowel elimination - Identify evidence-based practices After ingesting food and fluids, our body eliminates waste products through the urinary system and the gastrointestinal system. Nurses provide care for patients with commonly occuring elimination alterations, including urinary tract infections, urinary incontinence, urinary retention, constipation, diarrhea, and bowel incontinence. This chapter will provide an overview of these alterations and the associated nursing care. 16.2 Basic Concepts Open Resources for Nursing (Open RN) Let’s begin by reviewing the basic anatomy and physiology of the urinary and gastrointestinal systems. Urinary System The urinary system, also referred to as the renal system or urinary tract, consists of the kidneys, ureters, bladder, and urethra. The purpose of the urinary system is to eliminate waste from the body, regulate blood volume and blood pressure, control levels of electrolytes and metabolites, and regulate blood pH. The kidneys filter blood in the nephrons and remove waste in the form of urine. Urine exits the kidney via the ureters and enters the urinary bladder, where it is stored until it is expelled by urination (also referred to as voiding).National Institute of Diabetes and Digestive and Kidney Diseases. (2020, June). The urinary tract & how it works. U.S. Department of Health and Human Services. https://www.niddk.nih.gov/health-information/urologic-diseases/urinary-tract-how-it-works See Figure 16.1“Urinary_System_(Male).png” by BruceBlaus is licensed under CC BY-SA 4.0 for an image of the male urinary system. The female urinary system is similar except for a smaller urethra. A healthy adult with normal kidney function produces 800-2,000 mL of urine per day, depending on fluid intake, as well as the amount of fluid lost through sweating and breathing. The bladder typically holds about 360-480 mL of urine. As the bladder fills, it sends signals to the brain that it is time to urinate. The urinary tract includes two sets of muscles that work together as a sphincter, closing off the urethra to keep urine in the bladder until the brain sends signals to urinate. Urination occurs when the brain sends signals to the wall of the bladder to contract and squeeze urine out of the bladder and through the urethra. Frequency of urination depends on how quickly the kidneys produce urine and how much urine a person’s bladder can comfortably hold.National Institute of Diabetes and Digestive and Kidney Diseases. (2020, June). The urinary tract & how it works. U.S. Department of Health and Human Services. https://www.niddk.nih.gov/health-information/urologic-diseases/urinary-tract-how-it-works Normal urine should be clear, pale to light yellow in color, and not foul-smelling. However, some foods or medications may change the smell or color of urine. For instance, phenazopyridine (Pyridium), a common medication prescribed to treat the pain, frequency, and burning associated with urinary tract infections, can cause urine to appear orange.National Institutes of Health. (2019, August 28). Pyridium. DailyMed. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=165d01d4-a9f7-2293-e054-00144ff8d46c Nurses frequently monitor and document a patient’s urine output as part of the overall plan of care. It can be collected by placing a collection hat in the patient’s toilet and then measured in a graduated cylinder. If the patient has an indwelling catheter, the urine is emptied every shift from the catheter bag and measured in a graduated cylinder. For infants and toddlers, the number of daily wet diapers provides a general measure of urine output. For more specific measurement of urine output during hospitalization, wet diapers are weighed. Terms commonly used to document conditions related to the urinary tract are as follows: - Anuria: Absence of urine output, typically found during kidney failure, defined as less than 50 mL of urine over a 24-hour period. - Dysuria: Painful or difficult urination. - Frequency: The need to urinate several times during the day or at night (nocturia) in normal or less-than-normal volumes. It may be accompanied by a feeling of urgency.Maddukuri, G. (2021, January). Urinary frequency. Merck Manual Professional Version. https://www.merckmanuals.com/professional/genitourinary-disorders/symptoms-of-genitourinary-disorders/urinary-frequency - Hematuria: Blood in the urine, either visualized or found during microscopic analysis. - Oliguria: Decreased urine output, defined as less than 500 mL of urine in adults in a 24-hour period. In hospitalized patients, oliguria is further defined as less than 0.5 mL of urine per kilogram per hour for adults and children or less than 1 mL of urine per kilogram per hour for infants.Berry, C. (2020, November). Oliguria. Merck Manual Professional Version. https://www.merckmanuals.com/professional/critical-care-medicine/approach-to-the-critically-ill-patient/oliguria New oliguria should be reported to the health care provider because it can indicate dehydration, fluid retention, or decreasing kidney function. - Nocturia: The need to get up at night on a regular basis to urinate. Nocturia often causes sleep deprivation that affects a person’s quality of life.This work is a derivative of StatPearls by Leslie, Sajjad, & Singh and is licensed under CC BY 4.0 - Polyuria: Greater than 2.5 liters of urine output over 24 hours, also referred to as diuresis. Urine is typically clear with no color.A.D.A.M. Medical Encyclopedia [Internet]. Atlanta (GA): A.D.A.M., Inc.; c1997-2021. Urination – excessive amount; [updated 2021, Feb 8; cited 2021, Feb 16]. https://medlineplus.gov/ency/article/003146.htm New polyuria should be reported to the health care provider because it can be a sign of many medical conditions. - Pyuria: At least ten white blood cells in each cubic millimeter of urine in a urine sample, typically indicating infection. In severe infections, pus may be visible in the urine.Cherney, K. (2018, August 30). Everything you should know about pyuria. Healthline. https://www.healthline.com/health/pyuria See Figure 16.2“Pyuria2011.JPG” by James Heilman, MD is licensed under CC BY-SA 3.0 for an image of pyuria for a patient with urosepsis. - Urgency: A sensation of an urgent need to void.Maddukuri, G. (2021, January). Urinary frequency. Merck Manual Professional Version. https://www.merckmanuals.com/professional/genitourinary-disorders/symptoms-of-genitourinary-disorders/urinary-frequency Urgency can cause urge incontinence if the patient is not able to reach the bathroom quickly. View an activity reviewing the Vascular System of the Kidneys. Gastrointestinal System The gastrointestinal (GI) system includes the mouth, esophagus, stomach, small intestine, large intestine, and anus. See Figure 16.3“Blausen_0316_DigestiveSystem.png” by Blausen.com staff is licensed under CC BY 3.0 for an image of the gastrointestinal system. Ingested food and liquid are pushed through the GI tract by peristalsis, the involuntary contraction and relaxation of muscle creating wave-like movements of the intestines. The stomach mixes food and liquid with digestive enzymes and then empties into the small intestine. The muscles of the small intestine mix food with enzymes and bile from the pancreas, liver, and intestine and push the mixture forward for further digestion. Bacteria in the GI tract, called normal flora or microbiome, also assist with digestion. The walls of the small intestine absorb water and the digested nutrients into the bloodstream. As peristalsis continues, the waste products of the digestive process move into the large intestine. The large intestine absorbs water and changes the waste from liquid into stool. The rectum, at the lower end of the large intestine, stores stool until it is pushed out of the anus during a bowel movement.National Institute of Diabetes and Digestive and Kidney Diseases. (2017, December). Your digestive system & how it works. U.S. Department of Health and Human Services. https://www.niddk.nih.gov/health-information/digestive-diseases/digestive-system-how-it-works This section will focus on common alterations in bowel elimination, including constipation, diarrhea, and bowel incontinence. These alterations are common symptoms of several diseases and conditions of the gastrointestinal system. Nurses provide care to help manage these alterations. Terms related to alterations in bowel elimination include the following: - Black stools: Black-colored stools can be side effects of iron supplements or bismuth subsalicylate (Pepto-Bismol). - Rectal bleeding: Rectal bleeding refers to bright red blood in the stools, also referred to as hematochezia. It is a sign of bleeding from the lower GI tract. Rectal bleeding can range in severity from minimal drops of blood on the toilet tissue caused by hemorrhoids to severe bleeding in large amounts that are life-threatening and require emergency care.A.D.A.M. Medical Encyclopedia [Internet]. Atlanta (GA): A.D.A.M., Inc.; c1997-2021. Rectal bleeding; [updated 2021, Feb 8; cited 2021, Feb 16]. https://medlineplus.gov/ency/article/007741.htm New bleeding should always be reported to the health care provider. - Tarry stools: Stools that are black, sticky, and appear like tar are referred to as melena. Melena is typically caused by bleeding in the upper part of the gastrointestinal tract, such as the esophagus, stomach, or the first part of the small intestine, or due to the patient swallowing blood. The blood appears darker and tarry-looking because it undergoes digestion on its way through the GI tract.A.D.A.M. Medical Encyclopedia [Internet]. Atlanta (GA): A.D.A.M., Inc.; c1997-2021. Black or tarry stools; [updated 2021, Feb 8; cited 2021, Feb 16]. https://medlineplus.gov/ency/article/003130.htm#:~:text=Black%20or%20tarry%20stools%20with,used%20to%20describe%20this%20finding Bleeding from the upper part of the GI tract can also range from mild to life-threatening, depending upon the cause, and should always be reported to the health care provider. Read information about the “Gastrointestinal” system in Open RN Nursing Pharmacology. Newborns and Infants Meconium refers to the first bowel movement of a newborn that appears sticky and black to dark green in color. See Figure 16.4Meconium_Diaper.jpg” by Azoreg is licensed under CC BY-SA 3.0 for an image of meconium. The stool of a breastfed baby usually appears like a curdled yellow, while that of a formula-fed baby is more pasty. Breastfed babies often have bowel movements after every feeding. Formula-fed babies tend to have fewer bowel movements. Toddlers Toddlers usually begin the process of toilet training between 2 and 3 years old. Enuresis is the term used to describe incontinence when sleeping (i.e., bed-wetting). Enuresis in children is considered normal unless it continues past 7 or 8 years of age, when it should be addressed with a pediatrician. Toddlers often have undigested food in their bowel movements due to the intestinal system not fully digesting some foods, such as corn or grapes. Children School-aged children may be at risk for developing constipation due to delaying bowel movements during school times until they are in the privacy of their homes. Adults Adult females often develop urinary incontinence related to pregnancy and delivery, menopause, or vaginal hysterectomy. Adults males may have urgency and urinary retention with possible overflow urinary incontinence as their prostate enlarges. Adults over the age of 30 may develop nocturia. Older Adults Peristalsis typically slows as aging occurs. Older adults should be encouraged to increase fluids, fiber, and activity, as appropriate, to prevent constipation. If a patient is not able to meet the goal of a bowel movement with soft, formed stools every three days, then a bowel management program should be initiated. Now that we have reviewed the basic structure and function of the urinary and gastrointestinal systems, let’s review common alterations of urinary tract infection, urinary incontinence, urinary retention, constipation, diarrhea, and bowel incontinence in the following sections. 16.3 Urinary Tract Infection Open Resources for Nursing (Open RN) A urinary tract infection (UTI) is a common infection that occurs when bacteria, typically from the rectum, enter the urethra and infect the urinary tract. Infections can affect several parts of the urinary tract, but the most common type is a bladder infection (cystitis). Kidney infections (pyelonephritis) are more serious than a bladder infection because they can have long-lasting effects on the kidneys.Centers for Disease Control and Prevention. (2019, August 27). Urinary tract infection. https://www.cdc.gov/antibiotic-use/community/for-patients/common-illnesses/uti.html Some people are at higher risk of getting a UTI. UTIs are more common in females because their urethras are shorter and closer to the rectum, which makes it easier for bacteria to enter the urinary tract. Other factors that can increase the risk of UTIs include the following: - A previous UTI - Sexual activity, especially with a new sexual partner - Pregnancy - Age (Older adults and young children are at higher risk. Refer to the “Care of the Older Adult” chapter for more details about older adults.) - Structural problems in the urinary tract, such as prostate enlargementCenters for Disease Control and Prevention. (2019, August 27). Urinary tract infection. https://www.cdc.gov/antibiotic-use/community/for-patients/common-illnesses/uti.html Symptoms of a UTI include the following:Centers for Disease Control and Prevention. (2019, August 27). Urinary tract infection. https://www.cdc.gov/antibiotic-use/community/for-patients/common-illnesses/uti.html - Pain or burning while urinating (dysuria) - Frequent urination (frequency) - Urgency with small amounts of urine - Bloody urine - Pressure or cramping in the groin or lower abdomen - Confusion or altered mental status in older adults Symptoms of a more serious kidney infection (pyelonephritis) include fever above 101 degrees F (38.3 degrees C), shaking chills, lower back pain or flank pain (i.e., on the sides of the back), and nausea or vomiting.Centers for Disease Control and Prevention. (2019, August 27). Urinary tract infection. https://www.cdc.gov/antibiotic-use/community/for-patients/common-illnesses/uti.html It is important to remember that older adults with a UTI may not exhibit these symptoms but often demonstrate an increased level of confusion. Sometimes UTIs can spread to the blood (septicemia), leading to life-threatening infection called sepsis. Read more about sepsis in the “Infection” chapter. When a patient presents with symptoms of a UTI, the provider will order diagnostic tests, such as a urine dip, urinalysis, or urine culture. Read more about diagnostic tests in the “Assessment” section of the “Nursing Process” chapter. Interventions Antibiotics are prescribed for urinary tract infections. Nurses provide important patient education to patients with a UTI, such as the importance of finishing their antibiotic therapy as prescribed, even if they begin to feel better after a few days. Patients should also be encouraged to drink extra fluids to help flush bacteria from the urinary tract. Additional patient education regarding preventing future UTIs includes the following: - Urinate after sexual activity. - Stay well-hydrated and urinate regularly. - Take showers instead of baths. - Minimize douching, sprays, or powders in the genital area. - Teach girls when potty training to wipe front to back.Centers for Disease Control and Prevention. (2019, August 27). Urinary tract infection. https://www.cdc.gov/antibiotic-use/community/for-patients/common-illnesses/uti.html 16.4 Urinary Incontinence Open Resources for Nursing (Open RN) Urinary incontinence is the involuntary loss of urine. Although abnormal, it is a common symptom that can seriously affect the physical, psychological, and social well-being of affected individuals of all ages. It has been estimated that 1 in 5 women develop urinary incontinence, but many are too embarrassed to discuss the condition with their health care providers. Some believe it’s a normal part of aging that they have to live with. The result can be isolation and depression when they limit their activities and social interactions because of embarrassment due to incontinence. Nurses can greatly improve the quality of life for these patients by assessing for incontinence in a sensitive manner and then providing patient education about methods to prevent and/or manage incontinence. Types of Urinary Incontinence Continence is achieved through an interplay of the physiology of the bladder, urethra, sphincter, pelvic floor, and the nervous system coordinating these organs.McClurg, D., Pollock, A., Campbell, P., Hazelton, C., Elders, A., Hagen, S., & Hill, D. C. (2016). Conservative interventions for urinary incontinence in women: An overview of Cochrane systematic reviews. The Cochrane Database of Systematic Reviews, 2016(9). https://doi.org/10.1002/14651858.CD012337 A disruption in any of these areas can cause several types of urinary incontinence. - Stress urinary incontinence is the involuntary loss of urine with intra-abdominal pressure (e.g., laughing and coughing) or physical exertion (e.g., jumping). It is caused by weak pelvic floor muscles that is often the result of pregnancy and vaginal delivery, menopause, and vaginal hysterectomy.Tso, C. (2018, January 10). Postmenopausal women and urinary incontinence. American Nurse. https://www.myamericannurse.com/postmenopausal-women-urinary-incontinence/ - Urge urinary incontinence (also referred to as “overactive bladder”) is urine leakage caused by the sensation of a strong desire to void (urgency). It can be caused by increased sensitivity to stimulation by the detrusor muscle in the bladder or decreased inhibitory control of the central nervous system.Tso, C. (2018, January 10). Postmenopausal women and urinary incontinence. American Nurse. https://www.myamericannurse.com/postmenopausal-women-urinary-incontinence/ - Mixed urinary incontinence is a mix of urinary frequency, urgency, and stress incontinence.Tso, C. (2018, January 10). Postmenopausal women and urinary incontinence. American Nurse. https://www.myamericannurse.com/postmenopausal-women-urinary-incontinence/ - Overflow incontinence occurs when small amounts of urine leak from a bladder that is always full. This condition tends to occur in males with enlarged prostates that prevent the complete emptying of the bladder.National Institute of Aging. (2017, May 16). Urinary incontinence in older adults. U.S. Department of Health & Human Services. https://www.nia.nih.gov/health/urinary-incontinence-older-adults - Functional incontinence occurs in older adults who have normal bladder control but have a problem getting to the toilet because of arthritis or other disorders that make it hard to move quickly or manipulate zippers or buttons. Patients with dementia also have increased risk for functional incontinence. It is important to understand the types of incontinence so that appropriate interventions can be targeted to the cause. Assessment of Incontinence Assessment begins with screening questions during a health history, including questions such as, “Do you have any problems with the leakage or dribbling of urine? Do you ever have problems making it to the bathroom in time?” If a patient responds “Yes” to either of these questions, it is helpful to encourage them to start a voiding diary to record their urination habits and activities. The voiding diary should include the following: - When and how much the patient urinates - Urinary leakage and what the patient was doing when it happened (for example, running, biking, laughing) - Sudden urges to urinate - How often the patient wakes at night to use the bathroom - Type and volume of food and beverages and the time of intake - Medication use, such as diuretics, and the timing of administration - Any pain or problems experienced before, during, and after urinating (for example, sudden urges, difficulty urinating, dribbling urine, feeling as if the bladder is never empty, weak urine flow).Tso, C. (2018, January 10). Postmenopausal women and urinary incontinence. American Nurse. https://www.myamericannurse.com/postmenopausal-women-urinary-incontinence/ The provider will review information from the voiding diary, perform a physical assessment, and likely order diagnostic testing, such as a urine dip to check for a urinary tract infection, and urodynamic diagnostic testing that includes a variety of tests about bladder function, including filling, urine storage, and emptying.Tso, C. (2018, January 10). Postmenopausal women and urinary incontinence. American Nurse. https://www.myamericannurse.com/postmenopausal-women-urinary-incontinence/ Individualized treatment will be based on the assessment and tests to assess any structural abnormalities and bladder function. Interventions Nurses should use therapeutic communication with patients experiencing urinary incontinence to help them feel comfortable in expressing their fears, worries, and embarrassment about incontinence and work toward improving their quality of life. Let them know they’re not alone and that urinary incontinence is not something they have to live with. Provide education about pelvic floor muscle training exercises, timed voiding, lifestyle modification, and incontinence products. Encourage them to learn more about their condition so they can optimally manage it and improve their quality of life.Tso, C. (2018, January 10). Postmenopausal women and urinary incontinence. American Nurse. https://www.myamericannurse.com/postmenopausal-women-urinary-incontinence/ Nurses play an important role in educating patients about bladder control training to prevent incontinence. Bladder control training includes several these techniques: - Pelvic muscle exercises (also known as Kegel exercises) work the muscles used to stop urination, which can help prevent stress incontinence. Learn more about pelvic floor exercises in the box below. - Timed voiding can be used to help a patient regain control of the bladder. Timed voiding encourages the patient to urinate on a set schedule, for example, every hour, whether they feel the urge to urinate or not. The time between bathroom trips is gradually extended with the general goal of achieving four hours between voiding. Timed voiding helps to control urge and overflow incontinence as the brain is trained to be less sensitive to the sensation of the bladder walls expanding as they fill.National Institute of Aging. (2017, May 16). Urinary incontinence in older adults. U.S. Department of Health & Human Services. https://www.nia.nih.gov/health/urinary-incontinence-older-adults - Lifestyle changes can help with incontinence. Losing weight, drinking less caffeine (found in coffee, tea, and many sodas), preventing constipation, and avoiding lifting heavy objects may help with incontinence. Limiting fluid intake before bedtime and scheduling prescribed diuretic medication in the morning or early afternoon are also helpful.National Institute of Aging. (2017, May 16). Urinary incontinence in older adults. U.S. Department of Health & Human Services. https://www.nia.nih.gov/health/urinary-incontinence-older-adults - Protective products may be needed to protect the skin from breakdown and prevent leakage onto clothing. Incontinence underwear has a waterproof liner and built-in cloth pad to absorb large amounts of urine to protect skin from moisture and control odor. It is available in daytime and nighttime styles (designed to hold more urine). A product resembling a tampon is another option for females. It is made of absorbent fibers that support the urethra and prevents accidental leaks but doesn’t inhibit urination and won’t move or fall out during bowel movements.National Institute of Aging. (2017, May 16). Urinary incontinence in older adults. U.S. Department of Health & Human Services. https://www.nia.nih.gov/health/urinary-incontinence-older-adults Teaching Pelvic Floor Exercises Kegel exercises are designed to make your pelvic floor muscles stronger. Your pelvic floor muscles hold up your bladder and prevent it from leaking urine. - Start by finding the right muscles. There are two easy ways to do this: stop the stream of urine as you are urinating or imagine that you are trying to stop the passage of gas. Squeeze the muscles you would use to do both. If you sense a “pulling” feeling, you are squeezing the right muscles for pelvic exercises. Many people have trouble finding the right muscles. A doctor, nurse, or therapist can check to make sure you are doing the exercises correctly and targeting the correct muscles. - Find a quiet spot to practice so you can concentrate. Lie on the floor. Pull in the pelvic muscles and hold for a count of 3. Then relax for a count of 3. Work up to 10 to 15 repeats each time you exercise. - Complete pelvic exercises at least three times a day. Try to use three different positions while performing the exercises: lying down, sitting, and standing. For example, you can exercise while lying on the floor, sitting at a desk, or standing in the kitchen. Using all three positions while exercising makes these muscles their strongest. - Be patient. Most people notice an improvement after a few weeks, but the maximum effect may take up to 3-6 weeks. View a YouTube video about Kegel ExercisesMichigan Medicine. (2016, September 14). Better kegels: How to do kegel exercises, and why they work. [Video]. YouTube. All rights reserved. https://youtu.be/7C8uoq98x2A from Michigan Medicine. Patient education regarding other treatment options may be provided: - Biofeedback uses sensors to help a patient become more aware of signals from the body to regain control over the muscles in their bladder and urethra.National Institute of Aging. (2017, May 16). Urinary incontinence in older adults. U.S. Department of Health & Human Services. https://www.nia.nih.gov/health/urinary-incontinence-older-adults Mechanical devices, such as pessaries, support the urethra and can support vaginal prolapse to prevent or reduce urinary leakage. They come in various sizes and are professionally fitted by trained health care providers. They should be removed, cleaned, and reinserted regularly to prevent infection. Some of the devices, such as ring pessaries, can be removed and reinserted by the patient. They are similar to a diaphragm and can be removed or left in place for sexual intercourse.National Institute of Aging. (2017, May 16). Urinary incontinence in older adults. U.S. Department of Health & Human Services. https://www.nia.nih.gov/health/urinary-incontinence-older-adults - Anticholinergic medications, such as oxybutynin, may be prescribed to treat urge urinary incontinence and mixed urinary incontinence. They block the action of acetylcholine and provide an antispasmodic effect on smooth muscle to relieve symptoms. However, side effects include dry mouth, constipation, dizziness, and drowsiness, which can increase fall risk in older adults. - If bladder training and medications are not effective, surgery may be performed, such as a sling procedure or a bladder neck suspension.National Institute of Aging. (2017, May 16). Urinary incontinence in older adults. U.S. Department of Health & Human Services. https://www.nia.nih.gov/health/urinary-incontinence-older-adults 16.5 Urinary Retention Open Resources for Nursing (Open RN) Urinary retention is a condition when the patient cannot empty all of the urine from their bladder. Urinary retention can be acute (i.e., the sudden inability to urinate after receiving anesthesia during surgery) or chronic (i.e., a gradual inability to completely empty the bladder due to enlargement of the prostate gland in males). Urinary retention is caused by a blockage that partially or fully prevents the flow of urine or the bladder not being able to create a strong enough force to expel all the urine. In addition to causing discomfort, urinary retention increases the patient’s risk for developing a urinary tract infection (UTI). See Figure 16.5 “Normal-vs-enlarged-prostate.jpg” by Akcmdu9 is licensed under CC BY-SA 3.0 for an image of an enlarged prostate gland blocking the flow of urine from the bladder into the urethra. Symptoms of urinary retention can range from none to severe abdominal pain.National Institute of Diabetes and Digestive and Kidney Diseases. (n.d.). Urinary retention. U.S. Department of Health and Human Services. https://www.niddk.nih.gov/health-information/urologic-diseases/urinary-retention Health care providers use a patient’s medical history, physical exam finding, and diagnostic tests to find the cause of urinary retention. Nurses typically receive orders to measure post-void residual amounts when urinary retention is suspected. Post-void residual measurements are taken after a patient has voided by using a bladder scanner or inserting a straight urinary catheter to determine how much urine is left in the bladder. See the following box regarding how to perform a bladder scan at the bedside. Read about other diagnostic tests related to urinary retention, such as urodynamic testing and cystoscopy, under the “Applying the Nursing Process” section of this chapter.National Institute of Diabetes and Digestive and Kidney Diseases. (n.d.). Urinary retention. U.S. Department of Health and Human Services. https://www.niddk.nih.gov/health-information/urologic-diseases/urinary-retention Performing a Bladder Scan A bladder scanner is a portable, noninvasive medical device that uses sound waves to calculate the amount of urine in a patient’s bladder. Nurses use bladder scanners at the bedside to determine post-void residual urine amounts in patients to avoid the need to perform an invasive urinary catheterization. Typically the use of a bladder scan does not require a physician order, but be sure to check agency policy. After the patient voids and is lying in a supine position, turn on the device and indicate if the patient is male or female. (If the female has had a hysterectomy, then “male” is selected.) Apply warmed gel to the transducer head, and then place it approximately one inch above the symphysis pubis with the probe directed towards the bladder. Press the “scan” button, making sure to hold the scanner steady until you hear a beep. The bladder scanner will display the volume measured using a display with crosshairs. If the crosshairs are not centered on the urine displayed, adjust the probe and rescan until it is properly centered. If the post-void residual is greater than 300 mL, the provider should be notified and typically an order will be received for a straight urinary catheterization. Whenever possible, indwelling urinary catheterization (also referred to as a “Foley”) placement is avoided to reduce the patient’s risk of developing a catheter-associated urinary tract infection (CAUTI).Agency for Healthcare Research and Quality. (2020, October). Toolkit for reducing catheter-associated urinary tract infections in hospital units: Implementation guide – Appendix C. Sample bladder scan policy. https://www.ahrq.gov/hai/cauti-tools/impl-guide/implementation-guide-appendix-c.html View this following YouTube video to see a bladder scanner in useBladderScanDevice. (2017, Novemeber 13). How to use BladderScan Prime PlusTM by Diane Newman. [Video]. YouTube. All rights reserved. https://youtu.be/Q-sQu0T2oUY.: How to Use BladderScan Prime Plus™ by Diane Newman Interventions Treatment for urinary retention depends on the cause. It may include urinary catheterization to drain the bladder, bladder training therapy, medications, or surgery.National Institute of Diabetes and Digestive and Kidney Diseases. (n.d.). Urinary retention. U.S. Department of Health and Human Services. https://www.niddk.nih.gov/health-information/urologic-diseases/urinary-retention Read more about bladder training therapy under the “Urinary Incontinence” section. Alpha blockers, such as tamsulosin (Flomax), are used to treat urinary retention caused by an enlarged prostate. A surgery called transurethral resection of the prostate (TURP) may be performed to treat urinary retention caused by an enlarged prostate that is not responsive to medication. Read more about alpha-blocker medication (i.e., tamsulosin) in the “Autonomic Nervous System” chapter in Open RN Nursing Pharmacology. 16.6 Constipation Open Resources for Nursing (Open RN) Constipation is defined by NANDA-I as, “A decrease in normal frequency of defecation accompanied by difficult or incomplete passage of stool and/or passage of excessively hard, dry stool.”Herdman, T., & Kamitsuru, S. (2017). NANDA international nursing diagnoses: Definitions & classification 2018-2020 (11th ed.). Thieme Publishers Typically a patient is diagnosed with constipation if they have less than three bowel movements per week. Constipation can be caused by slowed peristalsis due to decreased activity, dehydration, lack of fiber, medications such as opioids, depression, or surgical procedures in the abdominal area. As the stool moves slowly through the large intestine, additional water is reabsorbed, resulting in the stool becoming hard, dry, and difficult to move through the lower intestines. See Figure 16.6“Bristol_stool_chart.svg” by Cabot Health, Bristol Stool Chart is licensed under CC BY-SA 3.0 for the Bristol Stool Chart used to assess the characteristics of stools ranging from constipation to diarrhea. The patient may experience associated symptoms such as rectal pressure, abdominal cramps, bloating, distension, and straining. Fecal impaction can occur when stool accumulates in the rectum, usually due to the patient not feeling the presence of stool or not using the toilet when the urge is felt. Large balls of hard stool need to be digitally removed or treated with mineral oil enemas. Interventions The goal of interventions implemented to treat constipation is to establish what is considered a normal bowel pattern for each patient and to set an expected outcome of a bowel movement at least every 72 hours regardless of intake. Treatment typically includes a prescribed daily bowel regimen, such as oral stool softeners (e.g., docusate) and a mild stimulant laxative (e.g., sennosides). Stronger laxatives (e.g., Milk of Magnesia or bisacodyl), rectal suppositories, or enemas are implemented when oral medications are not effective. Patients should be educated about the importance of increased fluids, increased dietary fiber, and increased activity to prevent constipation. Some food sources, such as prune juice, prunes, and apricots, are helpful in preventing constipation. Over-the-counter medication, such as methylcellulose or psyllium, can be used to increase dietary fiber. When administering these medications, mix in a full 8-ounce glass of water to avoid the development of an intestinal obstruction. Read more about laxatives used to treat constipation in the “Gastrointestinal” chapter in Open RN Nursing Pharmacology. Intestinal Obstruction or Paralytic Ileus Intestinal obstruction is a partial or complete blockage of the intestines so that contents of the intestine cannot pass through it. It can be caused by paralytic ileus, a condition where peristalsis is not propelling the contents through the intestines, or by a mechanical cause, such as fecal impaction. Patients who have undergone abdominal surgery or received general anesthesia are at increased risk for paralytic ileus. Other risk factors include the chronic use of opioids, electrolyte imbalances, bacterial or viral infections of the intestines, decreased blood flow to the intestines, or kidney or liver disease. If an obstruction blocks the blood supply to the intestine, it can cause infection and tissue death (gangrene).A.D.A.M. Medical Encyclopedia [Internet]. Atlanta (GA): A.D.A.M., Inc.; c1997-2021. Intestinal obstruction and ileus; [updated 2021, Feb 8; cited 2021, Feb 16]. https://medlineplus.gov/ency/article/000260.htm Symptoms of an intestinal obstruction or paralytic ileus include abdominal distention or a feeling of fullness, abdominal pain or cramping, inability to pass gas, vomiting, constipation, or diarrhea. Because of the common occurrence of paralytic ileus in postoperative patients, nurses routinely monitor for these symptoms, and diet orders are not upgraded until the patient is able to pass gas. Treatment may include insertion of an NG tube attached to suction to help relieve abdominal distention and vomiting until peristalsis returns. Obstructions may require surgery if the tube does not relieve the symptoms or if there are signs of tissue death.A.D.A.M. Medical Encyclopedia [Internet]. Atlanta (GA): A.D.A.M., Inc.; c1997-2021. Intestinal obstruction and ileus; [updated 2021, Feb 8; cited 2021, Feb 16]. https://medlineplus.gov/ency/article/000260.htm 16.7 Diarrhea Open Resources for Nursing (Open RN) Diarrhea is defined as having more than three unformed stools in 24 hours. It can cause dehydration, skin breakdown, and electrolyte imbalances. Diarrhea is caused by increased peristalsis causing the stool to move too quickly through the large intestines so that water is not effectively reabsorbed, resulting in loose, watery stools. Many conditions can cause diarrhea, such as infectious processes (bacteria, viruses, and protozoa), food poisoning, medications (such as antibiotics and laxatives), food intolerances, allergies, anxiety, and medical conditions like irritable bowel disease and Crohn’s disease, or dumping syndrome for patients receiving tube feeding. Antibiotic therapy also places patients at risk of developing Clostridium difficile (C-diff) due to the elimination of normal flora in the gastrointestinal tract. Patients with C-diff have very watery, foul-smelling stools, and transmission-based precautions are implemented to prevent the spread of infection. Read more about C-diff and transmission-based precautions in the “Infection” chapter in this text. Interventions Treatment of diarrhea includes promoting hydration with water or other fluids (e.g., sports drinks) that improve electrolyte status. Intravenous fluids may be required if the patient becomes dehydrated. Medications such as loperamide, psyllium, and anticholinergic agents may be prescribed to treat diarrhea causing dehydration. In some cases, rectal tubes may be prescribed to collect watery stool. However, strict monitoring is required due to possible damage to the rectal mucosa. Read about medications used to treat diarrhea in the “Gastrointestinal” chapter in Open RN Nursing Pharmacology. 16.8 Bowel Incontinence Open Resources for Nursing (Open RN) Bowel incontinence is the accidental loss of bowel control causing the unexpected passage of stool. Incontinence can range from leaking a small amount of stool or gas to not being able to control bowel movements. The rectum, anus, pelvic muscles, and nervous system must work together to control bowel movements. A patient must also be able to recognize and respond to the urge to have a bowel movement. If there is a problem with any of these factors, bowel incontinence can occur.A.D.A.M. Medical Encyclopedia [Internet]. Atlanta (GA): A.D.A.M., Inc.; c1997-2021. Bowel incontinence; [updated 2021, Feb 8; cited 2021, Feb 16]. https://medlineplus.gov/ency/article/003135.htm?utm_source=email&utm_medium=share&utm_campaign=mplus_share Causes of bowel incontinence include the following: - Ongoing (chronic) constipation, causing the anus muscles and intestines to stretch and weaken, leading to diarrhea and stool leakage - Fecal impaction with a lump of hard stool that partly blocks the large intestine - Long-term laxative use - Colectomy or bowel surgery - Lack of sensation of the need to have a bowel movement - Gynecological, prostate, or rectal surgery - Injury to the anal muscles in women due to childbirth - Nerve or muscle damage from injury, a tumor, or radiation - Severe diarrhea that causes leakage - Severe hemorrhoids or rectal prolapse - Stress of being in an unfamiliar environment - Emotional or mental health issuesA.D.A.M. Medical Encyclopedia [Internet]. Atlanta (GA): A.D.A.M., Inc.; c1997-2021. Bowel incontinence; [updated 2021, Feb 8; cited 2021, Feb 16]. https://medlineplus.gov/ency/article/003135.htm?utm_source=email&utm_medium=share&utm_campaign=mplus_share Interventions Many people feel embarrassed about bowel incontinence and do not share this information with their health care provider. It is essential for nurses to communicate therapeutically with patients experiencing bowel incontinence and let them know it can often be treated with simple changes such as diet changes, bowel retraining, pelvic floor exercises, or surgery.A.D.A.M. Medical Encyclopedia [Internet]. Atlanta (GA): A.D.A.M., Inc.; c1997-2021. Bowel incontinence; [updated 2021, Feb 8; cited 2021, Feb 16]. https://medlineplus.gov/ency/article/003135.htm?utm_source=email&utm_medium=share&utm_campaign=mplus_share Ask the patient to track the foods eaten to determine if certain types of foods cause problems. Foods that may lead to incontinence in some people include the following: - Alcohol - Caffeine - Dairy products (due to lactose intolerance) - Fatty, fried, or greasy foods - Spicy foods - Cured or smoked meats - Sweeteners such as fructose, mannitol, sorbitol, and xylitolA.D.A.M. Medical Encyclopedia [Internet]. Atlanta (GA): A.D.A.M., Inc.; c1997-2021. Bowel incontinence; [updated 2021, Feb 8; cited 2021, Feb 16]. https://medlineplus.gov/ency/article/003135.htm?utm_source=email&utm_medium=share&utm_campaign=mplus_share It is often helpful to add fiber to the diet to add bulk and thicken loose stool. To increase fiber, encourage the patient to eat whole grains with a goal of 30 grams of fiber a day. Other products, such as psyllium, can be used to add bulk to stools.A.D.A.M. Medical Encyclopedia [Internet]. Atlanta (GA): A.D.A.M., Inc.; c1997-2021. Bowel incontinence; [updated 2021, Feb 8; cited 2021, Feb 16]. https://medlineplus.gov/ency/article/003135.htm?utm_source=email&utm_medium=share&utm_campaign=mplus_share Bowel retraining involves teaching the body to have a bowel movement at a certain time of the day. This also includes encouraging the patient to go to the bathroom when feeling the urge to do so and not ignoring it. For some people, it is helpful to schedule this consistent time in the morning when the natural urge occurs after drinking warm fluids or eating breakfast. For other people, especially those with a neurological cause, a laxative may be scheduled every three days to stimulate the urge to have a bowel movement.A.D.A.M. Medical Encyclopedia [Internet]. Atlanta (GA): A.D.A.M., Inc.; c1997-2021. Bowel incontinence; [updated 2021, Feb 8; cited 2021, Feb 16]. https://medlineplus.gov/ency/article/003135.htm?utm_source=email&utm_medium=share&utm_campaign=mplus_share Patients can be educated about pelvic floor exercises to regain control of their anal sphincter muscle.A.D.A.M. Medical Encyclopedia [Internet]. Atlanta (GA): A.D.A.M., Inc.; c1997-2021. Bowel incontinence; [updated 2021, Feb 8; cited 2021, Feb 16]. https://medlineplus.gov/ency/article/003135.htm?utm_source=email&utm_medium=share&utm_campaign=mplus_shareRead more about pelvic floor exercises under the “Urinary Incontinence” section. Some patients can’t tell when it’s time to have a bowel movement or they can’t move well enough to get to the bathroom safely on their own. These patients require special care in long-term care settings. To promote effective bowel movements, assist them to the toilet after meals and when they feel the urge. Also, make sure the bathroom is comfortable and private.A.D.A.M. Medical Encyclopedia [Internet]. Atlanta (GA): A.D.A.M., Inc.; c1997-2021. Bowel incontinence; [updated 2021, Feb 8; cited 2021, Feb 16]. https://medlineplus.gov/ency/article/003135.htm?utm_source=email&utm_medium=share&utm_campaign=mplus_share If these simple treatments do not work, surgery may be needed to correct the problem. There are several types of procedures that a surgeon selects based on the cause of the bowel incontinence and the person’s general health.A.D.A.M. Medical Encyclopedia [Internet]. Atlanta (GA): A.D.A.M., Inc.; c1997-2021. Bowel incontinence; [updated 2021, Feb 8; cited 2021, Feb 16]. https://medlineplus.gov/ency/article/003135.htm?utm_source=email&utm_medium=share&utm_campaign=mplus_share Encourage patients with bowel incontinence to use special pads or undergarments to help them feel protected from accidents when they leave home. These products are available in pharmacies and in many other stores. 16.9 Applying the Nursing Process Open Resources for Nursing (Open RN) Now that we have discussed several alterations in elimination, let’s apply the nursing process to patients experiencing these conditions. Assessment Urinary Elimination Assessment Assessment of the urinary system includes asking questions about voiding habits, frequency, and if there is difficult or painful urination. The bladder may be palpated above the symphysis pubis for distention. If the patient has incontinence, the perineal area should be inspected for skin breakdown. If urinary retention is suspected, a post-void residual amount may be measured by using a bladder scanner or by straight urinary catheterization. For a summary of common signs and symptoms associated with alterations in urinary elimination, see the “Selected Defining Characteristics” listed in Table 16.9a under the “Diagnosis” subsection. Bowel Elimination Assessment Subjective assessment of the bowel system includes asking about the patient’s normal bowel pattern, the date of the last bowel movement, characteristics of the stool, and if any changes have occurred recently in stool characteristics or pattern. A normal pattern is typically one bowel movement every one to three days with stools having a soft or formed consistency. Refer to Figure 16.6“Bristol_stool_chart.svg” by Cabot Health, Bristol Stool Chart is licensed under CC BY-SA 3.0 under the “Constipation” section regarding using the Bristol Stool Chart to evaluate stool consistency. Based on the patient’s answers, additional questions can be included, such as bowel routines/toileting, the amount of fiber and fluid in the daily diet, daily activity, and the use of opioid medications. Keep in mind that patients who have recently undergone diagnostic procedures that include barium contrast can have significant hardening of the stool if the barium is not expelled within a day or two of the procedure. Patients are typically prescribed a stimulant laxative (such as Milk of Magnesia) to promote barium expulsion after these types of procedures. Additionally, patients who have recently had abdominal surgical procedures under general anesthesia are at increased risk of paralytic ileus. For a summary of common symptoms associated with alterations in urinary elimination, see the “Selected Defining Characteristics” listed in Table 16.9a under the “Diagnosis” subsection. The abdomen should be auscultated for bowel sounds, noting if they are present, hyperactive, or hypoactive in all four quadrants. If bowel sounds are absent or there are other signs of possible obstruction or paralytic ileus, the provider should be notified immediately. A light palpitation of the abdomen is performed to determine if there are tender areas, abnormal masses, or a firmness in the left lower quadrant indicating the presence of stool. During inpatient care, the patient is often requested to call the nurse when a bowel movement has occurred so the stool characteristics can be assessed. Document the amount (small, medium, or large), consistency (soft, formed, or hard) and color (brown or other color). Alterations in these characteristics can be caused by several conditions, such as infection, parasites, inflammatory conditions of the intestines, or gallbladder or liver conditions. Some patients have surgical diversions for diseases such as diverticulitis or cancer. Ostomies are surgical openings in the abdomen for the expulsion of stool into a bag-like appliance. An ileostomy is an opening created at the juncture of the small and large intestines, so the stool has a liquid consistency. A colostomy is placed farther along the large intestines, where more water has been absorbed, so the stool is more formed. Read about expected and unexpected findings during an abdominal assessment in the “Abdominal Assessment” chapter in Open RN Nursing Skills. Read about caring for patients with ostomies in the “Facilitation of Elimination” chapter in Open RN Nursing Skills. Urinary Diagnostic Tests There are several commonly ordered diagnostic tests for urinary conditions, such as a urine dip, urinalysis, urine culture, cystoscopy, and urodynamic flow studies. Urine Dip A urine dip test refers to a treated chemical strip (dipstick) being placed in a urine sample. Patches on the dipstick will change color to indicate the presence of substances such as white blood cells, protein, or glucose. See Figure 16.7“Chemstrip2.jpg” by J3D3 is licensed under CC BY-SA 3.0 for an image of a urine dipstick test. Urine is collected for a urine dip test in a clean container. Using the “clean catch” technique, the skin surrounding the urethra should be cleaned with a special towelette before the urine is collected. Catching the urine “midstream” is the goal, so request the patient to start urinating, stop, and then urinate into the container. Urinalysis A urinalysis includes a physical, chemical, and microscopic examination of urine by a lab technician. It requires collection of a “clean catch” urine sample in a sterile container. It involves checking the urine with a microscope for the following: - Color - Appearance (i.e., clear or cloudy) - Odor - pH level (acidity) - Substances not usually found in significant amounts in the urine, such as red blood cells, white blood cells, leukocyte esterase, bacteria, protein, glucose, ketones, and bilirubin - Cells, crystals, and castsMedlinePlus [Internet]. Bethesda (MD): National Library of Medicine (US); [updated 2020, Jun 9]. Urinalysis; [reviewed 2016, May 5; cited 2021, Feb 16]. https://medlineplus.gov/urinalysis.html See Figure 16.8“Pyuria2.JPG” by Bobjgalindo is licensed under CC BY-SA 4.0 for an image of white blood cells, referred to as pyuria, as seen on a urinalysis under a microscope. A urinalysis looks for evidence of infection, including elevated numbers of bacteria and white blood cells. A positive leukocyte esterase test or the presence of nitrite also supports the diagnosis of a UTI.LabTestsOnline.org. (2020, March 21). Urinary tract infection. https://labtestsonline.org/conditions/urinary-tract-infection Urine Culture A urine culture identifies the specific microbe causing a urinary tract infection. If this is the patient’s first, uncomplicated UTI of the lower urinary tract, the provider often assumes it is caused by the most common microbe, E. coli, and treats it with antibiotics without performing a culture. However, cultures are typically performed for patients with recurring UTIs or hospitalized patients at risk for hospital-associated infections.LabTestsOnline.org. (2020, August 12). Urine culture. https://labtestsonline.org/tests/urine-culture When interpreting urine culture results, the presence of a single type of bacteria growing at high colony counts is typically considered a positive urine culture. For clean catch samples that have been properly collected, cultures with greater than 100,000 colony forming units (CFU)/milliliter of one type of bacteria usually indicate infection.LabTestsOnline.org. (2020, August 12). Urine culture. https://labtestsonline.org/tests/urine-culture If a culture is positive, susceptibility testing is performed to guide treatment. Although a variety of bacteria can cause UTIs, most are due to Escherichia coli (E. coli) bacteria that are common in the digestive tract and routinely found in stool. Other bacteria that commonly cause UTIs include Proteus, Klebsiella, Enterobacter, Staphylococcus, and Acinetobacter. Susceptibility testing determines which antibiotics will inhibit the growth of the specific bacteria causing the infection. It is important for nurses to review culture results to verify the antibiotic therapy being administered has been found to be effective against the type of bacteria discovered in the culture. If there is any concern about the susceptibility results and current antibiotic therapy, the health care provider should be notified. A culture that is reported as “no growth in 24 or 48 hours” usually indicates that there is no infection. If a culture shows growth of several different types of bacteria, then it is likely due to contamination of the urine sample during collection. This is especially true in voided urine samples if the organisms present include Lactobacillus and/or other common nonpathogenic vaginal bacteria in women. The provider may request a repeat culture on a sample that is more carefully collected.LabTestsOnline.org. (2020, August 12). Urine culture. https://labtestsonline.org/tests/urine-culture Cystoscopy A cystoscopy is a procedure completed by a health care provider with a cystoscope, a small, thin tube with a camera on the end that is inserted into the urethra and into the bladder. See Figure 16.9“Diagram_showing_a_cystoscopy_for_a_man_and_a_woman_CRUK_064.svg” by Cancer Research UK is licensed under CC BY-SA 4.0 for an illustration of cystoscopy. Fluid is inserted to expand the bladder so the bladder walls can be visualized. Biopsy samples can be taken from abnormal tissue through the tube and then sent to a medical lab for analysis. The patient will feel the need to urinate when the bladder is full, but the bladder must stay full until the procedure is completed. A slight pinch may be felt if a biopsy sample is obtained. After the procedure, the patient should be encouraged to drink 4 to 6 glasses of water per day, as appropriate for their medical status. A small amount of blood may be present in the urine after the procedure, but if the bleeding continues after urinating three times, or if other signs of infection are present, the provider should be notified.A.D.A.M. Medical Encyclopedia [Internet]. Atlanta (GA): A.D.A.M., Inc.; c1997-2021. Cystoscopy; [updated 2021, Feb 8; cited 2021, Feb 16]. https://medlineplus.gov/ency/article/003903.htm Urodynamic Flow Test Urodynamic testing is any procedure that looks at how well the bladder, sphincters, and urethra are storing and releasing urine. Most urodynamic tests focus on the bladder’s ability to hold urine and empty steadily and completely. Urodynamic tests can also show whether the bladder is having involuntary contractions that cause urine leakage.National Institute of Diabetes and Digestive and Kidney Diseases. (2014, February). Urodynamic testing. U.S. Department of Health and Human Services. https://www.niddk.nih.gov/health-information/diagnostic-tests/urodynamic-testing Bowel Diagnostic Tests There are several common diagnostic tests related to bowel elimination, including stool-based tests, a colonoscopy, a barium enema, and an abdominal CT scan. Stool-Based Tests Stool samples can be tested for cancer, parasites, or for occult blood (i.e., hidden blood). Follow specific instructions from the lab for collecting the sample. The Guaiac-Based Fecal Occult Blood Test finds hidden blood in the stool. As a screening test for colon cancer, it is performed annually. Before the test, the patient should avoid many foods, such as red meat, melons, beets, and grapefruit for three days. They should not take aspirin or NSAIDs for seven days prior to the test. Stool samples from three separate bowel movements are smeared onto small paper cards and then returned to the medical lab for testing. If the test is positive (i.e., hidden blood is found), a follow-up colonoscopy is scheduled.American Cancer Society. (2020, June 29). Colorectal cancer screening tests. https://www.cancer.org/content/cancer/en/cancer/colon-rectal-cancer/detection-diagnosis-staging/screening-tests-used.html See Figure 16.10“Guaiac_test.jpg” by unknown author is in the Public Domain for an image of a typical card used to collect the stool smear for the test after a special solution has been applied. The blue color indicates a positive result for occult blood. The Stool DNA Test (also called Cologuard) looks for certain abnormal sections of DNA from cancer or polyp cells and also checks for occult blood. Specific collection kits, including a sample container, liquid preservative, and specific instructions are provided.American Cancer Society. (2020, June 29). Colorectal cancer screening tests. https://www.cancer.org/content/cancer/en/cancer/colon-rectal-cancer/detection-diagnosis-staging/screening-tests-used.html Colonoscopy During a colonoscopy, an instrument called a colonoscope is used. The colonoscope has a tiny camera attached to a long, thin tube that is inserted into the anus to check the entire colon and rectum. See Figure 16.11“Diagram_showing_a_colonoscopy_CRUK_060.svg” by Cancer Research UK is licensed under CC BY-SA 4.0 for an illustration of a colonoscopy. This procedure is used to screen patients for colon cancer. Screening is recommended to start at age 50 (or 45 for high-risk populations, including African Americans), and thereafter once every ten years or as prescribed by the provider. It is also used to evaluate the colon for inflamed tissue and abnormal growths or lesions. Before the procedure, the patient must complete a bowel prep that typically consists of a clear liquid diet and laxatives the day before the procedure to clean out the intestine so that everything can be seen clearly. Each provider typically has their own specific set of bowel prep instructions. Medications such as aspirin or anticoagulants may be ordered to be withheld for several days before the test. Patients are generally NPO after a specific time the night before the test. During the procedure, the patient receives sedative medication to stay relaxed. If a polyp is found, it can be removed during the procedure and sent for biopsy. Because air is inserted into the colon during procedure, the patient may feel bloated or have abdominal cramps and should be encouraged to freely pass the gas. Because this is typically an outpatient procedure, the patient is unable to drive after the test and requires transportation. Potential complications of the procedure are rare but include bleeding and perforation of the colon. The patient should receive written instructions for when to contact the health care provider or emergency services if complications occur.MedlinePlus [Internet]. Bethesda (MD): National Library of Medicine (US); [updated 2020, Feb 3]. Colonoscopy; [reviewed 2018, May 1; cited 2021, Feb 16]. https://medlineplus.gov/colonoscopy.html,American Cancer Society. (2019, January 14). Colonoscopy. https://www.cancer.org/treatment/understanding-your-diagnosis/tests/endoscopy/colonoscopy.html Barium Enema A barium enema is a special X-ray of the large intestine including the colon and rectum. This test may also be referred to a “lower GI series.” It is an older diagnostic test that has been mostly replaced by the colonoscopy test. Prior to the procedure, the patient completes a bowel preparation regimen to cleanse the colon, which typically includes a clear liquid diet for 1-3 days, followed by the administration of laxative medication and/or an enema. During the procedure, an X-ray is taken, and then an enema containing barium is administered. Additional X-rays are taken as the patient changes position to get different views of the colon. See Figure 16.12“Human_intestinal_tract,_as_imaged_via_double-contrast_barium_enema.jpg” by Glitzy queen00 at English Wikipedia is in the Public Domain for an image of barium enema results. After the procedure, it is normal for the patient to have white stools for a few days. The patient should be encouraged to drink extra fluids, as appropriate, and a laxative may be prescribed to prevent hard stools that can cause constipation.A.D.A.M. Medical Encyclopedia [Internet]. Atlanta (GA): A.D.A.M., Inc.; c1997-2021. Barium enima; [updated 2021, Feb 8; cited 2021, Feb 16]. https://medlineplus.gov/ency/article/003817.htm Abdominal CT Scan An abdominal CT scan is an imaging method that uses a series of X-rays to create cross-sectional pictures of the abdomen. Because of the series of X-rays, patients are exposed to more radiation than when receiving a traditional X-ray. They will lie on a narrow table that slides into the CT scanner where the machine’s X-ray beam rotates around them. A computer creates separate images, called slices, that can be viewed on a monitor or printed on film. Three-dimensional models of the area can be made by stacking the slices together.A.D.A.M. Medical Encyclopedia [Internet]. Atlanta (GA): A.D.A.M., Inc.; c1997-2021. Abdominal CT scan; [updated 2021, Feb 8; cited 2021, Feb 16]. https://medlineplus.gov/ency/article/003789.htm See Figure 16.13”UW_Medical_Center_PET-CT-Scan.jpg” by Clare McLean for UW Medicine is licensed under CC BY 3.0 for an image of a CT scan. A special dye, called contrast, is administered to patients before some tests so that certain areas show up better on the X-rays. If contrast is used, the patient may be required to be NPO for 4 to 6 hours before the test. Contrast can be administered orally or intravenously. Oral contrast has a chalky taste and will pass out of your body through the stools. Patients receiving IV contrast may feel a slight burning sensation, metallic taste in the mouth, or warm flushing of the body that resolves in a few seconds. Before sending the patient for a procedure using contrast, check for previous allergies to iodine or other contrast dyes. Some patients may be prescribed diphenhydramine or corticosteroids before receiving the contrast if they have had a previous allergic reaction. Verify their kidney status because IV contrast can worsen kidney function. If the patient is currently taking the antidiabetic medication metformin, there may be restrictions placed on the administration of metformin before or after the procedure. Jewelry should be removed before the procedure.A.D.A.M. Medical Encyclopedia [Internet]. Atlanta (GA): A.D.A.M., Inc.; c1997-2021. Abdominal CT scan; [updated 2021, Feb 8; cited 2021, Feb 16]. https://medlineplus.gov/ency/article/003789.htm After the procedure, encourage patients who have received contrast to increase their fluid intake to help eliminate it from their body, as appropriate. If they received barium, their stools will be light in color. Post-procedural laxatives are typically prescribed to prevent the stool from hardening, which can cause an impaction or obstruction. Diagnosis There are several nursing diagnoses related to alterations in elimination. Refer to a nursing care planning resource for current NANDA-I nursing diagnoses and evidence-based interventions. See Table 16.9a for common NANDA-I diagnoses related to elimination. Table 16.9a Common NANDA-I Nursing Diagnoses Related to Alterations in Elimination \| NANDA-I Diagnosis \| Definition \| Selected Defining Characteristics \| \|---\|---\|---\| \| Constipation \| Decrease in normal frequency of defecation accompanied by difficult or incomplete passage of stool and/or passage of excessively hard, dry stool \| \| \| Diarrhea \| Passage of loose, unformed stools \| \| \| Bowel Incontinence \| Involuntary passage of stool \| \| \| Stress Urinary Incontinence \| Sudden leakage of urine with activities that increase intraabdominal pressure \| \| \| Urge Urinary Incontinence \| Involuntary passage of urine occurring soon after a strong sensation or urgency to void \| \| \| Urinary Retention \| Inability to empty bladder completely \| \| Sample PES Statements Sample PES statements for the nursing diagnoses are as follows: - Constipation related to insufficient fluid and fiber intake as evidenced by decreased stool frequency, hypoactive bowel sounds, and straining with defecation. - Diarrhea associated with gastrointestinal irritation as evidenced by cramping, hyperactive bowel sounds, and greater than three liquid stools in 24 hours. - Bowel Incontinence related to generalized decline in muscle tone as evidenced by a constant passage of soft stool. - Stress Incontinence related to weak pelvic muscle floor muscles as evidenced by leakage of a small amount of urine when laughing and jumping. - Urinary Urge Incontinence related to ineffective toileting habits as evidenced by the inability to reach the toilet in time to avoid urine loss and frequently wet underclothes. - Urinary Retention associated with blockage in the urinary tract as evidenced by dribbling of urine in small amounts with frequent voiding and a reported sensation of bladder fullness. Outcome Identification See Table 16.9b for sample goals and outcome criteria associated with nursing diagnoses related to elimination alterations. Table 16.9b Sample Goals and Outcome Criteria for Alterations in Elimination \| Nursing Diagnosis \| Overall Goal \| SMART Outcomes \| \|---\|---\|---\| \| Constipation \| The patient will have a bowel movement every 1-3 days with soft, formed stool and ease of stool passage. \| The patient will have a bowel movement with soft, formed stool in the next 24 hours. \| \| Diarrhea \| The patient will have a regular bowel elimination pattern with soft, formed stool. \| The patient will report relief from cramping and fewer episodes of diarrhea in the next eight hours. \| \| Stress Incontinence \| The patient will have urinary continence as evidenced by no urine leakage with intra-abdominal pressure and dry underclothes and bedding. \| The patient will report fewer episodes of stress incontinence in their bladder log over the next month. \| \| Urge Incontinence \| The patient will have urinary continence as evidenced by adequate time to reach the toilet and dry underclothes and bedding. \| The patient will report fewer incontinence episodes over the next month. \| \| Urinary Retention \| The patient will experience improved urinary elimination as evidenced by complete emptying of the bladder and absence of urinary leakage. \| The patient will report a feeling of complete emptying of the bladder by next week. \| Planning Interventions Plan interventions customized to each patient’s alteration, cause of the condition, and related SMART outcomes. See interventions for each alteration under the corresponding sections earlier in this chapter. Implementing Interventions Assess a hospitalized patient’s bowel pattern and date of last bowel movement daily. Implement a bowel management plan as needed to achieve the goal of a bowel movement every one to three days to avoid constipation and impaction. Before administering laxatives and stool softeners, always assess the patient’s recent stool characteristics and withhold medication if loose stools or diarrhea are occurring. In the same manner, when administering medications for a patient with diarrhea, assess recent stool consistency and bowel pattern and withhold medication if the diarrhea is resolved or constipation is developing. For many patients, alterations in elimination require patient education to teach the patient and their caregivers how to manage these conditions at home. Keep in mind that patient education is an independent nursing intervention, so a provider order is not necessary to provide this important information. Evaluation Evaluate the effectiveness of interventions based on the SMART outcomes established for each patient and their situation. 16.10 Putting It All Together Patient Scenario Mrs. Jones is a 38-year-old woman who presents to the pediatrician office with her three-year-old daughter, Aubrey. Mrs. Jones explains that her daughter has been experiencing infrequent bowel movements. She states, “Aubrey only passes stool 1 to 2 times per week. She strains to pass the stool and it is dry and hard when it passes.” Aubrey nods and says, “My tummy hurts a lot when that happens.” Applying the Nursing Process Assessment: The nurse notes the mother’s report of Aubrey experiencing increased difficulty passing stool, infrequent bowel movements, and only passing stool one to two times per week with hard, dry feces. She records Aubrey’s complaint that her “tummy hurts a lot when that happens.” The nurse assesses Aubrey’s abdomen and finds it rounded and firm with decreased bowel sounds present in all four quadrants. Based on the assessment information that has been gathered, the nurse creates the following nursing care plan for Aubrey: Nursing Diagnosis: Constipation related to insufficient fluid and fiber intake as manifested by decreased stool frequency, hypoactive bowel sounds, straining with defecation, hard dry stools, and patient reports “my tummy hurts a lot when that happens.” Overall Goal: The patient will have soft bowel movements without difficulty. SMART Expected Outcome: The patient will have a soft, formed stool every 24-48 hours. Planning and Implementing Nursing Interventions: The nurse will provide education to the patient and her mother regarding the importance of adequate fluid sources and fiber intake in addition to medications prescribed by the provider. The nurse will encourage water for hydration and provide education regarding beverage sources that may contribute to constipation. The nurse will describe the value of fresh fruits, vegetables, and whole grains in diet and describe strategies for encouraging toddler consumption of these foods. The nurse will encourage scheduling regular times to attempt elimination. The nurse will provide positive reinforcement to the child regarding using of the toilet regularly for bowel elimination and encourage the mother to track bowel movements and intake using an elimination diary. Sample Documentation: Mother presents with the patient to the clinic reporting infrequent bowel movements. She states, “Aubrey only passes stool 1 to 2 times per week. She strains to pass the stool and it is dry and hard when it passes.” The patient reports, “My tummy hurts a lot when that happens.” The patient’s abdomen is firm and round with decreased bowel sounds present in all four quadrants. Patient education was provided to improve bowel elimination. Evaluation: The nurse calls Aubrey’s mother in two days. The mother reports that Aubrey had a soft, formed bowel movement on each of the past two days. The SMART outcome was initially “met.” The nurse encourages the mother to continue the planned interventions and to follow-up with the provider at the next clinic visit. 16.11 Learning Activities Open Resources for Nursing (Open RN) Learning Activities (Answers to “Learning Activities” can be found in the “Answer Key” at the end of the book. Answers to interactive activity elements will be provided within the element as immediate feedback.) An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=1748#h5p-94 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=1748#h5p-34 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=1748#h5p-35 XVI Glossary Open Resources for Nursing (Open RN) Anuria: Absence of urine output that is typically found during kidney failure. Can be defined as less than 50 mL of urine over a 24-hour period. Black stools: Black-colored stools can be caused by iron supplements or bismuth subsalicylate (Pepto-Bismol) taken for an upset stomach. Bowel incontinence: The loss of bowel control, causing the unexpected passage of stool. Bowel retraining: Involves teaching the body to have a bowel movement at a certain time of the day. Constipation: A decrease in normal frequency of defecation accompanied by difficult or incomplete passage of stool and/or passage of excessively hard, dry stool. Contrast: A special dye administered to patients before some diagnostic tests so that certain areas show up better on the X-rays. Diarrhea: More than three unformed stools in 24 hours. Dysuria: Painful or difficult urination. Enuresis: Incontinence when sleeping (i.e., bedwetting). Fecal impaction: A condition that occurs when stool accumulates in the rectum usually due to the patient not feeling the presence of stool or not using the toilet when the urge is felt. Large balls of soft stool may need to be digitally removed or treated with mineral oil enemas. Frequency: Urinary frequency is the need to urinate many times during the day or at night (nocturia) in normal or less-than-normal volumes. It may be accompanied by a feeling of urgency. Functional incontinence: Occurs in older adults who have normal bladder control but have a problem getting to the toilet because of arthritis or other disorders that make it hard to move quickly. Patients with dementia also have increased risk for functional incontinence. Hematuria: Blood in urine, either visualized or found during microscopic analysis. Intestinal obstruction: A partial or complete blockage of the intestines so that contents of the intestine cannot pass through it. Meconium: The black to dark green, sticky first bowel movement of a newborn. Melena: Black, sticky, tar-looking stools. Melena is typically caused by bleeding in the upper part of the gastrointestinal tract, such as the esophagus, stomach, or the first part of the small intestine, or due to the patient swallowing blood. The blood appears darker and tarry-looking because it undergoes digestion on its way through the GI tract. Mixed urinary incontinence: Urinary frequency, urgency, and stress incontinence. Nocturia: The need for a patient to get up at night on a regular basis to urinate. Nocturia often causes sleep deprivation that affects a person’s quality of life. Occult blood: Hidden blood in the stool not visible to the naked eye. Oliguria: Decreased urine output, defined as less than 500 mL urine in adults in a 24-hour period. In hospitalized patients, oliguria is further defined as less than 0.5 mL of urine per kilogram per hour for adults and children or less than 1 mL of urine per kilogram per hour for infants. Overflow incontinence: Occurs when small amounts of urine leak from a bladder that is always full. This condition tends to occur in males with enlarged prostates that prevent the complete emptying of the bladder. Paralytic ileus: A condition where peristalsis is not propelling the contents through the intestines. Peristalsis: The involuntary contraction and relaxation of the muscles of the intestine creating wave-like movements that push the digested contents forward. Polyuria: Greater than 2.5 liters of urine output over 24 hours; also referred to as diuresis. Urine is typically clear with no color. Postvoid residual: A measurement of urine left in the bladder after a patient has voided by using a bladder scanner or straight catheterization. Pyuria: At least ten white blood cells in each cubic millimeter of urine in a urine sample that typically indicates infection. In some cases, pus may be visible in the urine. Rectal bleeding: Bright red blood in the stools; also referred to as hematochezia. Stress urinary incontinence: The involuntary loss of urine on intra-abdominal pressure (e.g., laughing and coughing) or physical exertion (e.g., jumping). Tarry stools: Stools that are black and sticky that appear like tar; also referred to as melena. Urgency: A sensation of an urgent need to void. Urgency may be associated with urge incontinence. Urge urinary incontinence: Also referred to as “overactive bladder”; urine leakage accompanied by a strong desire to void. It can be caused by increased sensitivity to stimulation of the detrusor in the bladder or decreased inhibitory control of the central nervous system. Urinary retention: A condition when the patient cannot empty all of the urine from their bladder. Grief and Loss XVII 17.1 Grief and Loss Introduction Open Resources for Nursing (Open RN) Learning Objectives - Advocate for the ethical/legal concerns of the patient and family members making end-of-life decisions - Identify evidence-based practices associated with end of life care - Employ nursing measures to support palliative care during the dying process - Demonstrate respect for the cultural and spiritual beliefs of the patient, caregiver(s), and family members experiencing grief and loss - Outline available personal and community resources - Describe nursing responsibilities associated with postmortem care Have you ever experienced the loss of something important to you like a job, a relationship with a friend or significant other, or a pet? We all experience loss and grief at some point in our lives, with the ultimate loss being death. Nurses are typically the first line of support as they assist patients and their family members to cope with serious illness, feelings of loss, and the end of life. This chapter is based on a curriculum established by the End-of-Life Nursing Care Consortium (ELNEC), an international educational project sponsored by the American Association of Colleges of Nursing. The ELNEC project gives nurses and other health care professionals the knowledge and skills required to provide specialized care and positively impact the lives of patients and families facing serious illness and/or the end of life.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 This chapter will discuss concepts related to grief and loss and evidence-based interventions advocated by the ELNEC. 17.2 Basic Concepts Open Resources for Nursing (Open RN) Three major concepts associated with grieving are loss, grief, and mourning. Loss is the absence of a possession or future possession with the response of grief and the expression of mourning. The feeling of loss can be associated with the loss of health, changes in relationships and roles, and eventually the loss of life. After a patient dies, the family members and other survivors experience loss.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Grief is the emotional response to a loss, defined as the individualized and personalized feelings and responses that an individual makes to real, perceived, or anticipated loss. These feelings may include anger, frustration, loneliness, sadness, guilt, regret, and peace. Grief affects survivors physically, psychologically, socially, and spiritually. The grief process is not orderly and predictable. Emotional oscillation is normal and expected. There are times when the person experiencing the loss feels in control and accepting, and there are other times when the loss feels unbearable and they feel out of control.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 See Figure 17.1“Grief_and_loss_(16755561105).jpg” by Thomas8047 is licensed under CC BY 2.0 for an image of an individual experiencing grief. Mourning is the outward, social expression of loss. Individuals outwardly express loss based on their cultural norms, customs, and practices, including rituals and traditions. Some cultures may be very emotional and verbal in their expression of loss, such as wailing or crying loudly. Other cultures are stoic and show very little reaction to loss. Culture also dictates how long one mourns and how the mourners “should” act. The expression of loss is also affected by an individual’s personality and previous life experiences.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Types of Grief There are five different categories of grief: anticipatory grief, acute grief, normal grief, disenfranchised grief, and complicated grief. Anticipatory Grief Anticipatory grief is defined as grief before a loss, associated with diagnosis of an acute, chronic, and/or terminal illness experienced by the patient, family, or caregivers. Examples of anticipatory grief include actual or fear of potential loss of health, independence, body part, financial stability, choice, or mental function.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Sometimes anticipatory grief starts at the time of a terminal diagnosis and can proceed until the person dies. Both patients and their family members can feel anticipatory loss. The patient often anticipates the loss of independence, function, or comfort, which can cause significant pain and anxiety if not given the proper support. A patient may also have concrete fears such as the loss of the ability to drive, live independently, or maintain their current body image. They may also have grief regarding the loss of anticipated family experiences, such as celebrating the marriage of a child, the birth of a grandchild, an anniversary, or another significant life event. The family often starts grieving for the loss of their loved one before they die as they envision their life without their loved one in it. This type of grief has been shown to help cushion a person’s bereavement reaction.Kübler-Ross, E. (1969). On death and dying. The Macmillan Company. Acute Grief Acute grief begins immediately after the death of a loved one and includes the separation response and response to stress. During this period of acute grief, the bereaved person may be confused and/or uncertain about their identity or social role. They may disengage from their usual activities and experience disbelief and shock that their loved one is gone.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 See Figure 17.2“WWStoryRome.jpg” by Carptrash is licensed under CC BY-SA 3.0 for an image of a sculpture depicting acute grief. Normal Grief Normal grief includes the common feelings, behaviors, and reactions to loss. Normal grief reactions to a loss can include the following: - Physical symptoms such as hollowness in the stomach, tightness in the chest, weakness, heart palpitations, sensitivity to noise, breathlessness, tension, lack of energy, and dry mouth - Emotional symptoms such as numbness, sadness, fear, anger, shame, loneliness, relief, emancipation, yearning, anxiety, guilt, self-reproach, helplessness, and abandonment - Cognitive symptoms such as a state of depersonalization, confusion, inability to concentrate, dreams of the deceased, idealization of the deceased, or a sense of presence of the deceased - Behavioral signs such as impaired work performance, crying, withdrawal, overreactivity, changed relationships, or avoidance of reminders of the deceasedThis work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Acute grieving may take months and but can also take years, depending on the loss. No one ever truly gets over the loss, but there is an eventual reconnection with the world of the living as the relationship with the deceased changes.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Disenfranchised Grief Disenfranchised grief is grief over any loss that is not validated or recognized. Those affected by this type of grief do not feel the freedom to openly acknowledge their grief. Individuals at risk for disenfranchised grief are those who have lost loved ones to stigmatized illnesses or events, such as AIDS. Mothers and/or fathers may grieve over terminated pregnancies or stillborn babies. The loss of a previously severed relationship or divorce can contribute to this type of grief because the individual may not be able to mourn openly due to the circumstances surrounding the relationship. Complicated Grief Complicated grief is seen in 10-20% of individuals experiencing the death of a romantic partner and with higher estimates for parents who have lost a child. According to the ELNEC, there are four types of complicated grief, including chronic grief, delayed grief, exaggerated grief, and masked grief. Risk factors for developing complicated grief include sudden or traumatic death, suicide, homicide, a dependent relationship with the deceased, chronic illness, death of a child, multiple losses, unresolved grief from prior losses, concurrent stressors, witnessing a difficult dying process such as pain and suffering, lack of support systems, and lack of a faith system. Complicated grief may require professional assistance depending on its severity. Factors that contribute to complicated grief in older adults include lack of a support network, concurrent losses, poor coping skills, and loneliness.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 - Chronic Grief: Normal grief reactions that do not subside and continue over very long periods of time. - Delayed Grief: Normal grief reactions that are suppressed or postponed by the survivor consciously or unconsciously to avoid the pain of the loss. - Exaggerated Grief: An intense reaction to grief that may include nightmares, delinquent behaviors, phobias, and thoughts of suicide. - Masked Grief: Grief that occurs when the survivor is not aware of behaviors that interfere with normal functioning as a result of the loss. For example, an individual cancels lunch with friends so they can go to the cemetery daily to visit their loved one’s grave.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Stages of Grief There are several stages of grief that may occur following a loss. It can be helpful for nurses to have an understanding of these stages to recognize the emotional reactions as symptoms of grief so they can support patients and families as they cope with loss. Famed Swiss psychiatrist Elizabeth Kubler-Ross identified five main stages of grief in her book On Death and Dying.American Nurses Association. (2015). Nursing: Scope and standards of practice (3rd ed.). American Nurses Association. Patients and families may experience these stages along a continuum, move randomly and repeatedly from stage to stage, or skip stages altogether. There is no one correct way to grieve, and an individual’s specific needs and feelings must remain central to care planning. Kuber-Ross identified that patients and families demonstrate various characteristic responses to grief and loss. These stages include denial, anger, bargaining, depression, and acceptance, commonly referred to by the mnemonic “DABDA.” See Figure 17.3“Kubler-ross-grief-cycle-1-728.jpg” by U3173699 is licensed under CC BY-SA 4.0 for an illustration of the Kubler-Ross Grief Cycle. Keep in mind that these stages of grief not only occur due to loss of life, but also occur due to significant life changes such as divorce, loss of friendships, loss of a job, or diagnosis with a chronic or terminal illness.This work is a derivative of StatPearls by Oates & Maani and is licensed under CC BY 4.0 View the beginning of this YouTube video clipMovieclips. (2014, February 5). Steel Magnolias (8/8) movie CLIP – I wanna know why (1989) HD. [Video]. YouTube. All rights reserved. https://youtu.be/iZx1W6cHw-g from the movie Steel Magnolias that shows a mother demonstrating stages of the grieving process. Denial Denial occurs when the individual refuses to acknowledge the loss or pretends it isn’t happening. This stage is characterized by an individual stating, “This can’t be happening.” The feeling of denial is self-protective as an individual attempts to numb overwhelming emotions as they process the information. The denial process can help to offset the immediate shock of a loss. Denial is commonly experienced during traumatic or sudden loss or if unexpected life-changing information or events occur. For example, a patient who presents to the physician for a severe headache and receives a diagnosis of terminal brain cancer may experience feelings of denial. See Figure 17.4“Young-indian-with-disgusting-expression-showing-denial-with-hands-42509-pixahive.jpg” by Sukhjinder is licensed under CC0 for an image of a person reacting to unexpected news with denial. Anger Anger in the grief process often masks pain and sadness. The subject of anger can be quite variable; anger can be directed to the individual who was lost, internalized to self, or projected toward others. Additionally, an individual may lash out at those uninvolved with the situation or have bursts of anger that seemingly have no apparent cause. Health care professionals should be aware that anger may often be directed at them as they provide information or provide care. It is important that health care team members, family members, and others who become the target of anger seek to recognize that the anger and emotion are not a personal attack, but rather a manifestation of the challenging emotions that are a part of the grief process. If possible, the nurse can provide supportive presence and allow the patient or family member time to vent their anger and frustration while still maintaining boundaries for respectful discussion. Rather than focusing on what to say or not to say, allowing a safe place for a patient or family member to verbalize their frustration, sorrow, and anger can offer great support. See Figure 17.5“Child%27s_Angry_Face.jpg” by Babyaimeesmom is licensed under CC BY-SA 4.0 for an image of a patient experiencing anger. Bargaining Bargaining can occur during the grief process in an attempt to regain control of the loss. When individuals enter this phase, they are looking to find ways to change or negotiate the outcome by making a deal. Some may try to make a deal with God or their higher power to take away their pain or to change their reality by making promises to do better or give more of themselves if only the circumstances were different. For example, a patient might say, “I promised God I would stop smoking if He would heal my wife’s lung cancer.” Depression Feelings of depression can occur with intense sadness over the loss of a loved one or the situation. Depression can cause loss of interest in activities, people, or relationships that previously brought one satisfaction. Additionally, individuals experiencing depression may experience irritability, sleeplessness, and loss of focus. It is not uncommon for individuals in the depression phase to experience significant fatigue and loss of energy. Simple tasks such as getting out of bed, taking a shower, or preparing a meal can feel so overwhelming that individuals simply withdraw from activity. In the depression phase, it can be difficult for individuals to find meaning, and they may struggle with identifying their own sense of personal worth or contribution. Depression can be associated with ineffective coping behaviors, and nurses should watch for signs of self-medicating through the use of alcohol or drugs to mask or numb depressive feelings. See Figure 17.6“Depressed_(4649749639).jpg” by Sander van der Wel is licensed under CC BY-SA 2.0 for an image of a patient demonstrating feelings of depression. Acceptance Acceptance refers to an individual understanding the loss and knowing it will be hard but acknowledging the new reality. The acceptance phase does not mean absence of sadness but is the acknowledgement of one’s capabilities in coping with the grief experience. In the acceptance phase, individuals begin to re-engage with others, find comfort in new routines, and even experience happiness with life activities again. See Figure 17.7“Contentment_at_its_best.jpg” by Neha Bhamburdekar is licensed under CC BY-SA 4.0 of an image of a patient who has reached acceptance of the new reality related to his loss. Grief Tasks Kubler-Ross’s grief stages describe many feelings that individuals commonly experience while grieving loss. Other experts also describe the grieving process in terms of tasks that one must accomplish. These tasks include notification and shock, experiencing the loss, and reintegration.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 - Notification and shock: This phase occurs when a person first learns of the loss and experiences feelings of numbness or shock. The person may isolate themselves from others while processing this information. The first task for the person to complete is to acknowledge the reality of the loss by assessing and recognizing the loss. - Experiencing the loss: The second task involves experiencing the loss emotionally and cognitively. The person must work through the pain by reacting to, expressing, and experiencing the pain of separation and grief. - Reintegration: The third task involves reorganization and restructuring of family systems and relationships by adjusting to the environment without the deceased. The person must form a new reality without the deceased and adapt to a new role while also retaining memories of the deceased.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 As a nurse, you can greatly assist patients and families members as they move through the grieving process by being willing and committed to spending time with them. Listen to their stories, be present, and bear witness to their pain. Remember that you cannot fix everything, but taking time to assess their symptoms of grief helps you identify other resources for support. Palliative Care and Hospice There are specialty care areas related to the care of patients and their families experiencing loss and the grieving process. The specialties include palliative care and hospice care. Palliative care is a broad philosophy of care defined by the World Health Organization as improving the quality of life of patients with life-limiting illnesses, as well as their family members, through the prevention and relief of physical, psychosocial, and spiritual suffering.World Health Organization. (n.d.). Palliative care. http://www.who.int/cancer/palliative/definition/en/ In the United States, palliative care is further described as, “Patient and family-centered care that optimizes quality of life by anticipating, preventing, and treating suffering. Palliative care occurs throughout the continuum of care and involves the interdisciplinary team collaboratively addressing physical, intellectual, emotional, social, and spiritual needs and facilitating patient autonomy, access to information, and choice.”National Hospice and Palliative Care Organization. (2021). Explanation of palliative care. https://www.nhpco.org/palliative-care-overview/explanation-of-palliative-care/ Palliative care focuses on comfort and quality of life but also includes continuing curative treatment such as dialysis, chemotherapy, and surgery. Hospice care is a type of palliative care that addresses care for patients who are terminally ill when a health care provider has determined they are expected to live six months or less. Like palliative care, hospice provides comprehensive comfort care and support for the family, but in hospice, curative treatments are stopped. It is based on the idea that dying is part of the normal life cycle and supports the patient and family through the dying and grief process. It also supports the surviving family members through the bereavement process. Hospice care does not hasten death but focuses on providing comfort. Many patients decide to receive hospice care at home with the support of family, nurses, and hospice staff, but hospice services are also available across a variety of settings such as long-term care, assisted living facilities, hospitals, and prisons. In the United States, older adults enrolled in Medicare can choose to receive hospice care and stop receiving curative treatment. It is important to remember that stopping curative treatment does not mean discontinuing all medical treatment. For example, a patient with cancer who is no longer responding to chemotherapy can decide to enter hospice care and focus on comfort and quality of life. The chemotherapy treatment will stop, but other medical care, such as blood pressure medications or antibiotics to treat infection, will continue as long as they are helpful in promoting quality of life. Medicare will also pay for all related home durable medical equipment (such as a hospital bed and home oxygen therapy equipment) and all medications related to the terminal diagnosis (including pain medications).This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0,This work is a derivative of Introduction to Sociology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/introduction-sociology-2e/pages/1-introduction-to-sociology See Figure 17.8“hospice-1761276_1280.jpg” by truthseeker08 is licensed under CC0 for an image of a patient receiving hospice care. Unfortunately, instead of viewing hospice as a care option to promote quality of life and reduce suffering, many patients and their families associate hospice care with “giving up,” or as a “death sentence,” and are resistant to this type of care. For this reason, many health care teams advocate the implementation of palliative care until patients and their family members are ready to discuss hospice care. When a patient and their family members make the decision to implement home hospice, their desire is for the patient to comfortably spend their final days in their home environment. However, if the patient’s condition later becomes challenging for family members to manage at home, it can be very difficult to consider transferring the patient to a hospice inpatient unit at that time. It is often helpful to encourage patients and family members to tour alternative care agencies when considering hospice and be prepared if this decision is later warranted. Comfort Care Comfort care is a term commonly used in the acute care setting that is similar to palliative care and hospice. Comfort care occurs when the patient’s and medical team’s goals shift from curative intervention to symptom control, pain relief, and quality of life. However, there is no formal admission to hospice or palliative care that can impact insurance coverage. Rather than focusing on aggressive medical intervention, the focus changes to symptom control to provide the patient with the greatest degree of comfort possible as they approach their end of life. Read more about the National Coalition for Hospice and Palliative Care’s Palliative Care Guidelines. Ethical and Legal Considerations End-of-life care often includes unique complexities for the patient, family, and nurse. There may be times when what the physician or nurse believes to be the best treatment conflicts with what the patient desires. There may also be challenges related to decision-making that cause disagreements within a family or cause conflict with the treatment plan. Additional challenging factors include availability of resources and insurance company policies and programs. Despite these complexities, it is important for the nurse to honor and respect the wishes of the patient. Despite any conflicts in decision-making among health care providers, family members, and the patient, the nurse must always advocate for the patient’s wishes. Nurses should also be aware of the practice guidelines for ethical dilemmas stated in the American Nurses Association’s Standards of Professional Nursing Practice and Code of Ethics.American Nurses Association. (2015). Code of ethics for nurses with interpretive statements. American Nurses Association. https://www.nursingworld.org/practice-policy/nursing-excellence/ethics/code-of-ethics-for-nurses/coe-view-only/,National Institute on Aging. (2017, May 17). What are palliative care and hospice care? U.S. Department of Health & Human Services. https://www.nia.nih.gov/health/what-are-palliative-care-and-hospice-care These resources assist the nurse in implementing expected behaviors according to their professional role as a nurse. If complex ethical dilemmas occur, many organizations have dedicated ethics committees that offer support, guidance, and resources for complex ethical decisions. These committees can serve as support systems, share resources, provide legal insight, and make recommendations for action. The nurse should feel supported in raising concerns within their health care organization if they believe an ethical dilemma is occurring. Do-Not-Resuscitate Orders and Advance Directives Additional legal considerations when providing care at the end of life are do-not-resuscitate orders (DNR) orders and advance directives. A do-not-resuscitate (DNR) order is a medical order that instructs health care professionals not to perform cardiopulmonary resuscitation (CPR) if a patient’s breathing stops or their heart stops beating. The order is only written with the permission of the patient (or the patient’s health care power of attorney, if activated.) Ideally, a DNR order is set up before a critical condition occurs. CPR is emergency treatment provided when a patient’s blood flow or breathing stops that may involve chest compressions and mouth-to-mouth breathing, electric shocks to restart the heart, breathing tubes to open the airway, or cardiac medications. The DNR order only refers to not performing CPR and is recorded in a patient’s medical record. Wallet cards, bracelets, or other DNR documents are also available to have at home or in non-hospital settings. The decision to implement a DNR order is typically very difficult for a patient and their family members to make.A.D.A.M. Medical Encyclopedia [Internet]. Atlanta (GA): A.D.A.M., Inc.; c1997-2021. Do-not-resuscitate order; [updated 2021, June 9].https://medlineplus.gov/ency/patientinstructions/000473.htm Many people have unrealistic ideas regarding the success rates of CPR and the quality of life a patient experiences after being revived, especially for patients with multiple chronic diseases or those receiving palliative care. For example, a recent study found the overall rate of survival leading to hospital discharge for someone who experiences cardiac arrest is about 10.6 percent.Ouellette, L., Puro, A., Weatherhead, J., Shaheen, M., Chassee, T., Whalen, D., & Jones, J.. (2018). Public knowledge and perceptions about cardiopulmonary resuscitation (CPR): Results of a multicenter survey. American Journal of Emergency Medicine, 36(10), 1900-1901. https://doi: 10.1016/j.ajem.2018.01.103. Nurses can provide up-to-date patient education regarding CPR and its effectiveness based on the patient’s current condition and facilitate discussion about a DNR order. Advance directives include the health care power of attorney and living will. The health care power of attorney legally identifies a trusted individual to serve as a decision maker for health issues when the patient is no longer able to speak for themselves. It is the responsibility of this designated individual to carry out care actions in accordance with the patient’s wishes. A health care power of attorney can be a trusted family member, friend, or colleague who is of sound mind and is over the age of 18. They should be someone who the patient is comfortable expressing their wishes to and someone who will enact those desired wishes on the patient’s behalf. The health care power of attorney should also have knowledge of the patient’s wishes outlined in their living will. A living will is a legal document that describes the patient’s wishes if they are no longer able to speak for themselves due to injury, illness, or a persistent vegetative state. The living will addresses issues like ventilator support, feeding tube placement, cardiopulmonary resuscitation, and intubation. It is a vital means of ensuring that the health care provider has a record of one’s wishes. However, the living will cannot feasibly cover every possible potential circumstance, so the health care power of attorney is vital when making decisions outside the scope of the living will document. Read more about advance care planning at the National Institute on Aging and at Honoring Choices Wisconsin. Nurses must understand the health care practice legalities for the state in which they practice nursing. There can be practice issues in various states that raise additional ethical complexities for the practicing nurse. For example, Oregon, Washington, Vermont, and New Mexico all have laws that allow patients to participate in assisted dying practices involving assisted suicide or active euthanasia. In assisted suicide, the patient is provided the means to carry out suicide such as a lethal dose of medication. Most nursing organizations prevent a nurse from participating in assisted dying practices. Nurses must be aware of the Practice Act in their state and the legalities and ethical challenges of nursing actions surrounding complex issues such as assisted suicide, active euthanasia, and abortion. Care of the Family When caring for a patient who is nearing the end of life, the family members require nursing care as well. Fading away is a transition that families make when they realize their seriously ill family member is dying. Although they may have been previously told by a health care provider that their loved one would die from the illness, there is often a sudden realization their family member “is not going to get any better” when their health begins to significantly decline. With this realization comes the transition of fading away.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 There are various dimensions that both patients and family members experience during this fading away process: - Redefining: There is a shift for both patients and families from “what used to be” to “what is now.” - Burdening: As patients become more dependent, they may feel as if they are a burden to their family–physically, financially, emotionally, socially, and spiritually. Yet, family members typically do not feel the care they are providing is a burden, but rather, “something you do for someone you love.” - Searching for Meaning: Patients journey inward, seek spiritual reflection, and become more connected to important family members and friends. Family members may search for meaning inwardly through spiritual reflection or explore for meaning with family members and friends. - Living Day to Day: Patients who eventually find meaning in their illness live each day with a more positive attitude. Family members who try to “make the best of it” make efforts to enjoy the limited time left with their loved one. - Preparing for Death: Patients often want to leave a legacy. Spouses often want to meet every need of their ill spouse. Patients and family members may begin to make pre-arrangements for the funeral, as well as get their will and other financial matters in order. - Contending with Change: Patients and their family members change roles, social patterns, and work patterns. They know the life they used to have will soon be gone.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Nurses can assist patients and family members during the fading away transition by being present and actively listening. Suggestions regarding preparation for death can be made. Caregiver Support Most patients with chronic illness have family caregivers that are an extension of the health care team and work 24/7/365. They typically provide 70-80% of the care at home. It is important for nurses to assess the caregiver when seeing them with the patient in the home, clinic, hospital, or long-term setting and provide encouragement. It is helpful to acknowledge their work is very difficult and to praise them for their efforts.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 See Figure 17.9“140305-M-KL110-002_(13063045524).jpg” by U.S. Department of Defense Current Photos is licensed under CC0 for an image of a mother acting as caregiver and supporting her son’s health. What do caregivers want? Research shows they want the following: - Support, assistance, and practical help (e.g., finding others to assist with grocery shopping, going to the pharmacy, and food preparation) - Honest conversations with the health care team - Assurance their loved one is being honored - Inclusion in the decision-making - Desire to be listened to and their concerns heard - Remembrance as a good and compassionate caregiver - Assurance that they did all they possibly could for their loved oneThis work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Assess caregivers’ needs for further assistance, as well as their social support network. Assess their physical needs, sleep patterns, and ability to perform other responsibilities. Watch for signs of declining health, clinical depression, or signs of increased use of alcohol and drugs. Listen to their stories and provide presence, active listening, and touch. Assist them in identifying and using support systems and refer them to resources and support groups in the community as needed.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Cultural Considerations Regarding Death When assessing patients, family members, and caregivers, it is important to respect their values, beliefs, and traditions related to health, illness, family caregiver roles, and decision-making. Information gathered through this comprehensive assessment is used to develop a nursing care plan that incorporates culturally sensitive resources and strategies to meet the needs of patients and their family members.American Association of Colleges of Nursing. (2021). End-of-life-care (ELNEC). https://www.aacnnursing.org/ELNEC See Figure 17.10Mourning_in_Shanghai_(1).jpg” by Medalofdead is licensed under CC BY-SA 4.0 for an image of a community grieving. Nurses can acquire knowledge about how different cultural beliefs influence a patient and their family members’ decision-making, approach to illness, pain, spirituality, grief, dying, death, and bereavement. See Table 17.2 for a brief comparison of various spiritual beliefs about death.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0,Pasero, C., & MacCaffery, M. (2010). Pain assessment and pharmacological management (1st ed.). Mosby. To review holistic nursing care that addresses the spiritual needs of patients and their significant others, refer to the “Spirituality” chapter. Table 17.2 Comparison of Spiritual Beliefs about DeathPasero, C., & MacCaffery, M. (2010). Pain assessment and pharmacological management (1st ed.). Mosby. \| Religion \| Beliefs Pertaining to Death \| Preparation of the Body \| Funeral \| \|---\|---\|---\|---\| \| Christian (Catholic and Protestant) \| Belief in Jesus Christ, the Bible, and an afterlife are central, although differences in interpretation exist in the various denominations. Catholics receive a sacrament called “anointing of the sick” when approaching the end of life. \| Organ donation and autopsy are permitted. \| Individuals are buried in cemeteries. Some denominations accept cremation as an alternative. Funerals or celebration of life services are typically held in a funeral home or church. \| \| Jewish \| Tradition cherishes life but death itself is not viewed as a tragedy. Views on an afterlife vary with the denomination (Reform, Conservative, or Orthodox). \| Autopsy and embalming are forbidden under ordinary circumstances. Open caskets are not permitted. \| Funeral is held as soon as possible after death. Dark clothing is worn at the funeral and after burial. It is forbidden to bury the deceased on the Sabbath or during festivals. Three mourning periods may be held after the burial, with Shiva being the first that occurs seven days after burial. \| \| Buddhist \| Both a religion and way of life with the goal of enlightenment. Life is believed to be a cycle of death and rebirth. \| Goal is a peaceful death. Statue of Buddha may be placed at the bedside as the person is dying. Organ donation is not permitted. Incense is lit in the room following death. \| Family washes and prepares the body after death. Cremation is preferred, but if buried, deceased are typically dressed in regular daily clothes instead of fancy clothing. Monks may be present at the funeral and lead the chanting. \| \| Native American \| Beliefs vary among tribes. Sickness is thought to mean that one is out of balance with nature. It is thought that ancestors can guide the deceased. Death is perceived as a journey to another world. Family may or may not be present for death. \| Preparation of the body may be done by family. Organ donation is generally not preferred. \| Various practices differ with tribes. Among the Navajo, hearing an owl or coyote is a sign of impending death, and the casket is left slightly open so the spirit can escape. Navajo and Apache tribes believe that spirits of the deceased can haunt the living. The Comanche tribe buries the dead in the place of death when possible or in a cave. \| \| Hindu \| Beliefs include reincarnation where a deceased person returns in the form of another, as well as Karma. \| Organ donation and autopsy are acceptable. Death and dying must be peaceful. It is customary for the body to not be left alone until cremated. \| Prefer cremation within 24 hours after death. Ashes are often scattered in sacred rivers. \| \| Muslim \| Believe in an afterlife and that the body must be quickly buried so that the soul may be freed. \| Embalming and cremation are not permitted. Autopsy is permitted for legal or medical reasons only. After death, the body should face Mecca or the East. The body should be prepared by a person of the same gender. \| Burial takes place as soon as possible. Women and men sit separately at the funeral. Flowers and excessive mourning are discouraged. The body is usually buried in a shroud and is buried with the head pointing toward Mecca. \| Read more about funeral traditions around the globe at the following link: Death is not the end: Fascinating funeral traditions from around the globe. A Good Death Death is a physical, psychological, social, and spiritual event. Family members who witness the last weeks, days, hours, and minutes of their loved one’s life will remember the death for all their lives. Although death is often perceived negatively in the American culture, research has found several themes that define a “good death” when nurses and the interdisciplinary team are caring for dying patients and their families:Karnes, B. (2009). Gone from my sight: The dying experience. Barbara Karnes Books. - Patient preferences are met, including preferences for the dying process (i.e., where and with whom) and preparation for death (i.e., advanced directives, funeral arrangements). - The patient is pain-free with emotional well-being. - The family is prepared for death and supportive of patient’s preferences. - Dignity and respect are demonstrated for the patient. - The patient has a sense of life completion (i.e., saying goodbye and feeling life was well-lived). - Spirituality and religious comfort are provided. - Quality of life was maintained (i.e., maintaining hope, pleasure, gratitude) - There is a feeling of trust/support/comfort from the nurse and interdisciplinary team.Karnes, B. (2009). Gone from my sight: The dying experience. Barbara Karnes Books. Nurses are often present during these final days and moments with patients during this difficult and sacred time.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Read more about nursing care performed during this time in the “Care During the Final Hours” section. See Figure 17.11“Dignity_Rainbow.jpg” by Klemdy is licensed under CC BY-SA 4.0 for an image of a statue named “Dignity Rainbow.” Bereavement Bereavement includes grief (the inner feelings) and mourning (the outward reactions) after a loved one has died. A bereavement period is the time it takes for the mourner to feel the pain of the loss, mourn, grieve, and adjust to the world without the presence of the deceased. Bereavement can take a physical toll on a survivor. It is associated with an increased risk of myocardial infarction and cardiomyopathy for survivors, and widows and widowers have an increased chance of dying after their spouses die.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 See Figure 17.12“Mourning,_Lette_Valeska.jpg” by Lette Valeska is licensed under CC BY-SA 3.0 for an image depicting bereavement by family members. A bereaved person should be encouraged to talk about the death and understand their feelings are normal. They should allow for sufficient time for expression of grief and should postpone significant decisions such as changing jobs or moving. It is also important to encourage them to focus on their spirituality to enhance coping during this difficult time.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 See Figure 17.13“meditation-1350599_960_720.jpg” by brenkee is licensed under CC0. for an image depicting spirituality demonstrated by a bereaved family member. Americans often deny the need to express grief or feel the pain that accompanies a loss. However, although painful, both are beneficial to healing. As part of the interdisciplinary health team, nurses are often at the front line of helping patients and family members cope with their feelings of loss and grief. The nursing role during the bereavement period includes the following: - Enhancing coping - Assessing and facilitating spirituality - Facilitating the grieving process by supporting the patient and survivors to feel the loss, express the loss, and move through the tasks of grief - Communicating assessments and interventions with the interdisciplinary teamThis work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Children Children who have experienced the loss of a parent, sibling, grandparent, or friend experience grief based on their developmental stage. It can be normal grief or complicated grief. Children may be limited in their ability to verbalize and describe their feelings and grief. See Figure 17.14“sad-72217_960_720.jpg” by PublicDomainPictures is licensed under CC0 for an image of a grieving child. Symptoms of grief in younger children include nervousness, uncontrollable rages, frequent sickness or accidents, rebellious behavior, hyperactivity, nightmares, depression, compulsive behavior, memories fading in and out, excessive anger, overdependence on the remaining parent, denial, and/or disguised anger. Children may not understand that death is permanent until they are in preschool or older. It is important to use the word “death” and not euphemisms like “gone to sleep” or “gone away.”This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Symptoms of grief in older children include difficulty concentrating, forgetfulness, decreased academic performance, insomnia or sleeping too much, compulsiveness, social withdrawal, antisocial behavior, resentment of authority, overdependence, regression, resistance to discipline, suicidal thoughts or actions, nightmares, symbolic dreams, frequent sickness, accident proneness, overeating or undereating, truancy, experimentation with alcohol or drugs, depression, secretiveness, sexual promiscuity, or running away from home.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Play is the universal language of children, so nurses should use it therapeutically when possible. Encouraging children that their grief is “normal” gives them comfort. Refer children, parents, and families to grief specialists as indicated. Make sure families are aware of local support groups.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Parents and Grandparents For parents, the death of a child can be devastating with a great need for bereavement support. For grandparents, the grief can be twofold as they experience their own grief, in addition to witnessing the grief of their child (the parent). Studies have shown that grandparents’ grief is seldom acknowledged.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 See Figure 17.15“Sarcophagus,_marble,_mourning_for_child,_100-200_AD,_AM_Agrigento,_121062.jpg” by Zde is licensed under CC BY-SA 4.0 for an image of a sculpture depicting mourning for a child. For more information on support for parents experiencing infant loss, go to http://nationalshare.org/ Spouses The death of a husband or wife is well recognized as an emotionally devastating event, being ranked on life event scales as the most stressful of all possible losses. The intensity and persistence of the pain associated with this type of bereavement is thought to be due to the emotional marital bonds linking husbands and wives to each other. Spouses are co-managers of home and family, companions, sexual partners, and fellow members of larger social units. Therapeutic Communication Tips When communicating with the bereaved, it is more important to listen and be present rather than say the “right words.” It is also helpful to simply encourage silence. However, these phrases should be avoided because they can create barriers in therapeutic communication: - Avoid statements like, “I know/can imagine/understand how you feel.” Even if you have been through a similar situation, you don’t know how the survivor feels. Instead say, “I’m sorry you have to go through this…” or “I know this is hard…” - Don’t minimize the individual’s grief reaction with a statement like, “You should be over this by now.” Instead, say, “This process takes time, so don’t feel as if you need to rush through it.” - Avoid statements that minimize the significance of the loss, such as, “At least you had a good life with them.” Instead, focus on exploring their feelings related to the loss, such as, “Tell me what your relationship was like.”This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Completion of the Grieving Process Grief work is never completely finished because there will always be times when a memory, object, song, or anniversary of the death will cause feelings of loss for the survivor. However, healing occurs and is characterized by the following: - The pain of the loss is lessened. - The survivor has adapted to life without the deceased. - The survivor has physically, psychologically, and socially “let go.”This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Letting go is a difficult process. One can let go and still find love and true meaning in the relationship they had with their loved one. Letting go does not mean cutting oneself off from the memories, but adapting to the loss and the continued bonds with the deceased.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 See Figure 17.16“Candle_burning.jpg” by NCCo at English Wikipedia is licensed under CC BY-SA 3.0 for a depiction of letting go by lighting a candle in memory of the deceased. Self-Care It is important for nurses to recognize that providing end-of-life care can have a significant impact on them. A nurse’s grief might be exacerbated when patient loss is unexpected or is the result of a traumatic experience. For example, an emergency room nurse who provides care for a child who died as a result of a motor vehicle accident may find it difficult to cope with the loss and resume their normal work duties. Grief can also be compounded when loss occurs repeatedly in one’s work setting or after providing care for a patient for a long period of time. In some health care settings, especially during the COVID-19 pandemic, nurses do not have time to resolve grief from a loss before another loss occurs. Compassion fatigue and burnout occur frequently with nurses and other health care professionals who experience cumulative losses that are not addressed therapeutically. Compassion fatigue is a state of chronic and continuous self-sacrifice and/or prolonged exposure to difficult situations that affect a health care professional’s physical, emotional, and spiritual well-being. This can lead to a person being unable to care for or empathize with someone’s suffering. Burnout can be manifested physically and psychologically with a loss of motivation. It can be triggered by workplace demands, lack of resources to do work professionally and safely, interpersonal relationship stressors, or work policies that can lead to diminished caring and cynicism.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 See Figure 17.17“Burnout_At_Work_-_Occupational_Burnout.jpg” by Microbiz Mag is licensed under CC BY 2.0 for an image depicting a nurse at home experiencing burnout due to exposure to multiple competing demands of work, school, and family responsibilities. Self-care is important to prevent compassion fatigue and burnout. It is important for nurses to recognize the need to take time off, seek out individual healthy coping mechanisms, or voice concerns within their workplace. Prayer, meditation, exercise, art, and music are examples of healthy coping mechanisms that nurses can use to progress through their individual grief experience. Additionally, many organizations sponsor employee assistance programs that provide counseling services. These programs can be of great value and benefit in allowing individuals to voice their individual challenges with patient loss. In times of traumatic patient loss, many organizations hold debriefing sessions to allow individuals who participated in the care to come together to verbalize their feelings. These sessions are often held with the support of chaplains to facilitate individual coping and verbalization of feelings. (Read more about the role of chaplains in the “Spirituality” chapter.) Throughout your nursing career, there will be times to stop and pay attention to warning signs of compassion fatigue and burnout. Here are some questions to consider: - Has my behavior changed? - Do I communicate differently with others? - What destructive habits tempt me? - Do I project my inner pain onto others?This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 By becoming self-aware, you can implement self-care strategies to prevent compassion fatigue and burnout. Use the following “A’s” to assist in building resilience, connection, and compassion: - Attention: Become aware of your physical, psychological, social, and spiritual health. What are you grateful for? What are your areas of improvement? This protects you from drifting through life on autopilot. - Acknowledgement: Honestly look at all you have witnessed as a health care professional. What insight have you experienced? Acknowledging the pain of loss you have witnessed protects you from invalidating the experiences. - Affection: Choose to look at yourself with kindness and warmth. Affection prevents you from becoming bitter and “being too hard” on yourself. - Acceptance: Choose to be at peace and welcome all aspects of yourself. By accepting both your talents and imperfections, you can protect yourself from impatience, victim mentality, and blame.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 In addition to self-care strategies, it is helpful for nurses to obtain additional education in end-of-life care. See the following hyperlink for more information about obtaining a palliative care certificate for your portfolio. Read more about online end-of-life curriculum available on the American Association of Colleges of Nursing’s End-of-Life-Care Curriculum web page. 17.3 Applying the Nursing Process to Grief Open Resources for Nursing (Open RN) Grieving a loss is a normal process that has implications for both patient and family well-being. NANDA formally recognizes the dimensions of grief with the nursing diagnoses of Grieving and Complicated Grieving. Recall that grief can be experienced due to many types of loss, in addition to death. For example, when patients receive a diagnosis of breast cancer, they may demonstrate signs of various stages of grief, such as denial, anger, bargaining, depression, and acceptance. When undergoing mastectomy and chemotherapy, the patient may grieve over the loss of prior body image. Communities can also experience grief. For example, when a town experiences a significant tragedy, such as a devastating flood or a tornado, there can be widespread community grief as families grieve the loss of life, property, or a previous way of life. In these situations, nurses are cognizant of the multiple factors that may impact an individual’s health and grieving process. Identifying these factors can help ensure that appropriate resources are mobilized to facilitate coping and progression through the grief process. Assessment Grief assessment includes the patient, family members, and significant others. It begins when a patient is diagnosed with an acute, chronic, or terminal illness and/or when the patient is admitted to a hospital, nursing facility, or assisted living facility. It continues throughout the course of a terminal illness for the patient, family members, and significant others and then continues through the bereavement period for the survivors. During the bereavement period, the nurse monitors for symptoms of complicated grief.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Grief can be manifested by physical, emotional, and cognitive symptoms. Physical symptoms can occur, such as feeling ill, headaches, tremors, muscle aches, exhaustion, insomnia, loss of appetite, or weight loss or gain. Cognitive symptoms may occur, such as lack of concentration, confusion, and hallucinations. Emotional symptoms, such as anxiety, guilt, anger, fear, sadness, helplessness, or feelings of relief may occur. These symptoms of grief and loss can be manifested in many different ways and can vary from day to day. Manifestations of grief are unique to the individual and may be influenced by one’s age, culture, resources, and previous experiences with loss. Additionally, as patients cope with grief and loss, it is important for the nurse to recognize that support is often needed by their family members.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Any behavior that may endanger the patient or family should be reported to the health care provider, such as symptoms of depression, suicidal ideation, or symptoms lasting greater than six months. Diagnoses Consult a nursing care planning resource when selecting nursing diagnoses for patients and their family members experiencing grief. See Table 17.3 for definitions and selected defining characteristics of the NANDA-I diagnoses Grieving and Complicated Grieving while also keeping in mind the previous discussion in this chapter regarding stages and tasks of normal grief. Table 17.3 NANDA-I Nursing Diagnoses Related to GrievingHerdman, T., & Kamitsuru, S. (2017). NANDA international nursing diagnoses: Definitions & classification 2018-2020 (11th ed.). Thieme Publishers, pp. 335, 339-341. \| NANDA-I Diagnosis \| Definition \| Selected Defining Characteristics \| \|---\|---\|---\| \| Grieving \| A normal, complex process that includes emotional, physical, spiritual, social, and intellectual responses and behaviors by which individuals, families, and communities incorporate an actual, anticipated, or perceived loss into their daily lives. \| \| \| Complicated Grieving \| A disorder that occurs after the death of a significant other, in which the experience of distress accompanying bereavement fails to follow normative expectations and manifests in functional impairment. \| \| Examples See the following for examples of PES statements related to Grieving and Complicated Grieving: - A patient diagnosed with metastatic cancer is advised they have less than six months to live. They begin to move through the stages of grief as they assimilate this information. A sample NANDA-I diagnosis in current PES format is: “Grieving related to anticipatory loss as evidenced by detachment, disorganization, and alteration in activity level.” The nurse would plan and implement interventions to enhance coping for this patient. - A patient’s husband died two years ago, and she continues to be preoccupied with thoughts about her husband. Her grown children live several hours away, and she becomes isolated and unable to complete daily activities, such as cleaning the house and grocery shopping. A sample PES statement is: “Complicated Grieving related to insufficient social support as evidenced by avoidance of decreased functioning and preoccupation with thoughts about her deceased husband.” The nurse would plan interventions to facilitate grief work while also arranging for assistance with ADLs and IADLs in the patient’s home. Outcome Identification Goal setting and outcome identification for patients and family members experiencing grief are customized to the specific situation and focus on grief resolution. Grief resolution is evidenced by the following indicators: - Resolves feelings about the loss - Verbalizes reality and acceptance of loss - Maintains living environment - Seeks social supportAckley, B., Ladwig, G., Makic, M. B., Martinez-Kratz, M., & Zanotti, M. (2020). Nursing diagnosis handbook: An evidence-based guide to planning care (12th ed.). Elsevier, pp. 144-147, 434-444. For the nursing diagnosis of Grieving and Complicated Grieving, a sample goal is, “The patient will experience grief resolution.” A sample SMART outcome is, “The patient will discuss the meaning of the loss to their life in the next 2 weeks.”Ackley, B., Ladwig, G., Makic, M. B., Martinez-Kratz, M., & Zanotti, M. (2020). Nursing diagnosis handbook: An evidence-based guide to planning care (12th ed.). Elsevier, pp. 144-147, 434-444. Planning and Implementing Interventions Nurses are in the ideal position to assist patients with identifying and expressing their feelings related to loss. The most important intervention that nurses can provide is active listening and offering a supportive presence. Actively listening to the bereaved helps them express their feelings and relate the emotions and feelings related to the loss. Interventions to facilitate grief resolution focus on coping enhancement, anticipatory grieving interventions, and grief work facilitation. Coping Enhancement Interventions to enhance coping can be implemented for patients and families experiencing any type of actual, anticipated, or perceived loss. Sample interventions include the following:National Cancer Institute. (n.d.). Grief, bereavement, and coping with loss (PDQ) – Health professional version. U.S. Department of Health and Human Services. https://www.cancer.gov/about-cancer/advanced-cancer/caregivers/planning/bereavement-hp-pdq#section/all - Assist the patient in identifying short- and long-term goals. - Assist the patient in examining available resources to meet the goals. - Assist the patient in breaking down complex steps into small, manageable steps. - Encourage relationships with others who have common interests and goals. - Assist the patient to solve problems in a constructive manner. - Appraise the effect of a patient’s life situation on roles and relationships. - Appraise and discuss alternative responses to the situation. - Use a calm, reassuring approach. - Provide an atmosphere of acceptance. - Help the patient identify information they are most interested in obtaining. - Provide factual information regarding medical diagnosis, treatment, and prognosis. - Provide the patient with realistic choices about certain aspects of care. - Encourage an attitude of realistic hope as a way of dealing with hopelessness. - Seek to understand the patient’s perspective of a stressful situation. - Discourage decision-making when the patient is under severe stress. - Acknowledge the patient’s cultural and spiritual background and encourage use of spiritual resources, if desired. - Encourage verbalization of feelings, perceptions, and fears. - Encourage family involvement, as appropriate. - Assist the patient to identify positive strategies to deal with limitations and manage needed lifestyle or role changes. - Instruct the patient on the use of relaxation techniques. See Figure 17.18“423588130-huge.jpg” by Jacob Lund is used under license from Shutterstock.com for an image of a nurse enhancing a patient’s ability to cope with their illness through active listening and touch. Anticipatory Grieving Interventions Anticipatory grieving refers to a grief reaction that occurs in anticipation of an impending loss. Recall that anticipatory grieving can be related to impending death of oneself or a loved one, but it can also occur in anticipation of other losses, such as the loss of a body part due to scheduled surgery or the loss of one’s home due to a move to a long-term care facility. Interventions to facilitate resolution of anticipatory grieving include the following:Ackley, B., Ladwig, G., Makic, M. B., Martinez-Kratz, M., & Zanotti, M. (2020). Nursing diagnosis handbook: An evidence-based guide to planning care (12th ed.). Elsevier, pp. 144-147, 434-444. - Develop a trusting relationship with the patient and family members by using presence and other therapeutic communication techniques. - Keep the patient and family members apprised of the patient’s ongoing condition as much as possible. - Keep the family informed of the patient’s needs for physical care and support in symptom control, and inform them about health care options at the end of life, including palliative care, hospice care, and home care. - Actively listen as the patient grieves for their own death or loss. Normalize the patient’s expressions of grief. - Discuss the patient’s preferred place of death and document their wishes. - Ask family members about having adequate resources to care for themselves and the critically ill family member. - Recognize caregiver role strain in family members providing long-term care at home. - Listen to the family member’s story. - Encourage family members to show their caring feelings and talk with the family members. - Recognize and respect different feelings and wishes from the patient and their family members. - Refer the patient and family members to counselors or chaplains for spiritual care as appropriate. Grief Work Facilitation Grief work facilitation assists patients and family members in resolution of a significant loss. Sample interventions include the following:National Cancer Institute. (n.d.). Grief, bereavement, and coping with loss (PDQ) – Health professional version. U.S. Department of Health and Human Services. https://www.cancer.gov/about-cancer/advanced-cancer/caregivers/planning/bereavement-hp-pdq#section/all - Identify the loss. - Assist the patient to identify the initial reaction to the loss. - Listen to expressions of grief. - Encourage discussion of previous loss experiences. - Encourage the verbalization of memories of the loss. - Make empathetic statements about grief. - Encourage identification of greatest fears concerning the loss. - Educate about stages and tasks of the grieving process, as appropriate. - Support progression through personal grieving stages. - Assist in identifying personal coping strategies. - Encourage implementation of cultural, religious, and social customs associated with the loss. - Answer children’s questions about the loss and encourage discussion of feelings. - Identify sources of community support. - Reinforce progress made in the grieving process. - Assist in identifying modifications needed in lifestyle. Community Resources Bereavement follow-up with families is a component of hospice programs and includes formal activities and events to promote closure and acceptance. Many hospices have nondenominational memorial services to honor patients. Family members and staff are invited to participate, which can be effective at helping individuals find closure. Other formal types of support can include organized support groups to facilitate discussion and coping. Individual, group counseling, or psychotherapy are other methods that can assist the bereaved in coping with their loss. See additional resources for family members in the following box. Additional Resources for Grief and Loss Evaluation It is always important to evaluate the effectiveness of interventions implemented. Nurses assess the effectiveness of interventions in helping individuals cope and work through the grief process based on the customized outcome criteria established for their situation. 17.4 Palliative Care Management Open Resources for Nursing (Open RN) Now that we have discussed basic concepts and the nursing process related to the grieving process, let’s discuss more details regarding providing palliative care. Nurses provide palliative care whenever caring for patients with chronic disease. As the disease progresses and becomes end-stage, the palliative care they provide becomes even more important. As previously discussed, palliative care is “patient and family-centered care that optimizes quality of life by anticipating, preventing, and treating suffering. Palliative care occurs throughout the continuum of care and involves the interdisciplinary team collaboratively addressing physical, intellectual, emotional, social, and spiritual needs and facilitating patient autonomy, access to information, and choice.”This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Providing care at the end of life is similar for patients with a broad variety of medical diagnoses. It addresses multiple dimensions of care, including physical, psychological, social, and spiritual aspects: - Physical: Functional ability, strength/fatigue, sleep/rest, nausea, appetite, constipation, and pain - Psychological: Anxiety, depression, enjoyment/leisure, pain, distress, happiness, fear, and cognition/attention - Social: Financial burden, caregiver burden, roles/relationships, affection, and appearance - Spiritual: Hope, suffering, the meaning of pain, religiosity, and transcendenceThis work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 The interdisciplinary team manages pain and other symptoms, assists with difficult medical decisions, and provides additional support to patients, family members, and caregivers. Nurses have the opportunity to maintain hope for patients and family members by providing excellent physical, psychosocial, and spiritual palliative care. Nursing interventions begin immediately after the initial medical diagnosis and continue throughout the continuum of care until the end of life. As a patient approaches end-of-life care, nursing interventions include the following: - Eliciting the patient’s goals for care - Listening to the patient and their family members - Communicating with members of the interdisciplinary team and advocating for the patient’s wishes - Managing end-of-life symptoms - Encouraging reminiscing - Facilitating participating in religious rituals and spiritual practices - Making referrals to chaplains, clergy, and other spiritual supportThis work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 While providing palliative care, it is important to remain aware that some things cannot be “fixed”: - We cannot change the inevitability of death. - We cannot change the anguish felt when a loved one dies. - The perfect words or interventions rarely exist, so providing presence is vital.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 The Palliative Care Network of Wisconsin contain excellent resources for nurses providing care for seriously ill patients. View the “Fast Facts” page for extensive information about palliative care and end of life topics. Management of Common Symptoms Many patients with serious, life-limiting illnesses have common symptoms that the nurse can assess, prevent, and manage to optimize their quality of life. These symptoms include pain, dyspnea, cough, anorexia and cachexia, constipation, diarrhea, nausea and vomiting, depression, anxiety, cognitive changes, fatigue, pressure injuries, seizures, and sleep disturbances. Good symptom management improves quality of life and functioning at all states of chronic illness. Nurses play a critical role in recognizing these symptoms and communicating them to the interdisciplinary team for optimal management. The plan of care should always be based on the patient’s goals and their definition of quality of life.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 These common symptoms are discussed in the following subsections. Pain Pain is frequently defined as “whatever the experiencing person says it is, existing whenever he says it does.”Pasero, C. (2018). In memoriam: Margo McCaffery, American Journal of Nursing, 118(3),17. https://doi: 10.1097/01.NAJ.0000530929.65995.42 When a patient is unable to verbally report their pain, it is important to assess nonverbal and behavioral indicators of pain. The goal is to balance the patient’s desire for pain relief, along with their desire to manage side effects and oversedation. There are many options available for analgesics. Reassure a patient that reaching their goal of satisfactory pain relief is achievable. Read more about pain management in the “Comfort” chapter. See Figure 17.19“a0dcf563-9393-4606-8302-c8f649e43895_rw_1200.jpg” by Flóra Borsi is licensed under CC BY-NC-ND 4.0 for an image illustrating a patient experiencing pain. Dyspnea Dyspnea is a subjective experience of breathing discomfort and is the most reported symptom by patients with life-limiting illness. Dyspnea can be extremely frightening. Assessing dyspnea can be challenging because the patient’s respiratory rate and oxygenation status do not always correlate with the symptom of breathlessness.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 See Figure 17.20“1737708011-huge” by CGN089 is used under license from Shutterstock.com for an image of a patient experiencing dyspnea. When assessing dyspnea, include the following components: - Ask the patient to rate the severity of their breathlessness on a scale of 0-10 - Assess their ability to speak in sentences, phrases, or words - Assess the patient’s anxiety - Observe respiratory rate and effort - Measure oxygenation status (i.e., pulse oximetry or ABG) - Auscultate lung sounds - Assess for the presence of chest pain or other pain - Assess factors that improve or worsen breathlessness - Evaluate the impact of dyspnea on functional status and quality of lifeThis work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 If you suspect that new dyspnea is caused by an acute condition, report assessment findings immediately to a health care provider. However, in end-stage disease, dyspnea can be a chronic condition that is treated with pharmacological and nonpharmacological management. The dosage should be titrated to the patient’s desired goals for relief of dyspnea without over sedation. Nonpharmacological interventions for dyspnea include pursed-lip breathing, energy conservation techniques, fans and open windows to circulate air, elevation of the patient bed, placing the patient in a tripod position, and relaxation techniques such as music and a calm, cool environment. Patient education can also reduce anxiety.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Read more about nonpharmacological interventions for dyspnea in the “Oxygenation” chapter. Cough A cough can be frustrating and debilitating for a patient, causing pain, fatigue, vomiting, and insomnia. See Figure 17.21“1728210124-huge.jpg” by Pheelings media is used under license from Shutterstock.com for an image of a patient with a chronic cough. Coughing is frequently present in advanced diseases such as chronic obstructive pulmonary disease (COPD), heart failure (HF), cancer, and AIDS. There are several potential causes of a cough. Medications that can be used to control a cough are opioids, dextromethorphan, and benzonatate. Guaifenesin can be used to thin thick secretions, and anticholinergics (such as scopolamine) can be used for high-volume secretions. Anorexia and Cachexia Anorexia (loss of appetite or loss of desire to eat) and cachexia (wasting of muscle and adipose tissue due to lack of nutrition) are commonly found in advanced disease. See Figure 17.22“hospice-1794912_960_720.jpg” by truthseeker08 is licensed under CC0 for an image of a patient with cachexia. Weight loss is present in both conditions and is associated with decreased survival. Unfortunately, aggressive nutritional treatment does not improve survival or quality of life and can actually create more discomfort for the patient.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Assessment of anorexia and cachexia focuses on understanding the patient’s experience and concerns, as well as determining potentially reversible causes. Referral to a dietician may be needed. Read more about nutritional assessment in the “Nutrition” chapter. Interventions for anorexia and cachexia should be individualized for each patient with the goal being eating for pleasure for those at the end of life. Patients should be encouraged to eat their favorite foods, as well as select foods that are high in calories and easy to chew. Small, frequent meals with pleasing food presentation are important. Family members should be aware that odors associated with cooking can inhibit eating. The patient may need to be moved away from the kitchen or cooking times separated from eating times.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Medication may be prescribed to increase intake, such as mirtazapine or olanzapine. Prokinetics such as metoclopramide may be helpful in increasing gastric emptying. Medical marijuana or dronabinol may also be useful. In some cases, enteral nutrition is helpful for patients who continue to have an appetite but cannot swallow.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Patient and family member education about anorexia at the end of life is important. Nurses should be aware that many family members perceive eating as a way to “get better” and are distressed to see their loved one not eat. After listening respectfully to their concerns, explain that the patient may feel more discomfort when forcing themselves to eat. Constipation Constipation is a frequent symptom in many patients at the end of life for many factors, such as low intake of food and fluids, use of opioids, chemotherapy, and impaired mobility. Constipation is defined as having less than three bowel movements per week. The patient may experience associated symptoms such as rectal pressure, abdominal cramps, bloating, distension, and straining. See Figure 17.23“abdominal-pain-2821941_960_720.jpg” by derneuemann is licensed under CC0 for an image of a patient experiencing constipation. The goal is to establish what is considered normal for each patient and to have a bowel movement at least every 72 hours regardless of intake. Treatment includes a bowel regimen such as oral stool softeners (i.e., docusate) and a stimulant (i.e., sennosides). Rectal suppositories (i.e., bisacodyl) or enemas should be considered when oral medications are not effective or the patient can no longer tolerate oral medications.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Read more about managing constipation in the “Elimination” chapter. Diarrhea Diarrhea is defined as having more than three unformed stools in 24 hours. Diarrhea can be especially problematic for patients receiving chemotherapy, pelvic radiation, or treatment for AIDS. It can cause dehydration, skin breakdown, and electrolyte imbalances and dramatically affect a person’s quality of life. It can also be a huge burden for caregivers.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Early treatment of diarrhea includes promoting hydration with water or fluids that improve electrolyte status (i.e., sports drinks). Intravenous fluids may be required based on the patient’s disease stage and goals for care. Medications such as loperamide, psyllium, and anticholinergic agents may also be prescribed. Read more about managing diarrhea in the “Elimination” chapter. Nausea and Vomiting Nausea is common in advanced disease and is a dreaded side effect of many treatments for cancer. Assessment of nausea and vomiting should include the patient’s history, effectiveness of previous treatment, medication history, frequency and intensity of episodes of nausea and vomiting, and activities that precipitate or alleviate nausea and vomiting.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Nonpharmacological interventions for nausea include eating meals and fluids at room temperature, avoiding strong odors, avoiding high-bulk meals, using relaxation techniques, and listening to music therapy.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Antiemetic medications, such as prochlorperazine and ondansetron, may be prescribed. Read more information about managing nausea in the “Antiemetics” section of the Gastrointestinal chapter in Open RN Nursing Pharmacology. Depression Patients who have a serious life-threatening illness will normally experience sadness, grief, and loss, but there is usually some capacity for pleasure. Persistent feelings of helplessness, hopelessness, and suicidal ideation are not considered a normal part of the grief process and should be treated. Undertreated depression can cause a decreased immune response, decreased quality of life, and decreased survival time. Evaluation of depression requires interdisciplinary assessment and referrals to social work and psychiatry may be needed.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Antidepressants such as serotonin selective reuptake inhibitors (i.e., fluoxetine, paroxetine, sertraline, or citalopram) are generally prescribed as first-line treatment of depression. Other medication may be prescribed if these medications are not effective. Nonpharmacological interventions for depression may include the following: - Promoting and facilitating as much autonomy and control as possible - Encouraging patient and family participation in care, thus promoting a sense of control and reducing feelings of helplessness - Reminiscing and life review to focus on life accomplishments and to promote closure and resolution of life events. See Figure 17.24“photos-256887_960_720.jpg” by jarmoluk is licensed under CC0 for an image of reminiscing with pictures. - Grief counseling to assist patients and families in dealing with loss - Maximizing symptom management - Referring to counseling for those experiencing inability to cope - Assisting the patient to draw on previous sources of strength, such as faith, religious rituals, and spirituality - Referring for cognitive behavioral techniques to assist with reframing negative thoughts into positive thoughts - Teaching relaxation techniques - Providing ongoing emotional support and “being present” - Reducing isolation - Facilitating spiritual supportThis work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 A suicide assessment is critical for a patient with depression. It is important for nurses to ask questions, such as these: - Do you have interest or pleasure in doing things? - Have you had thoughts of harming yourself? - If yes, do you have a plan for doing so? To destigmatize the questions, it is helpful to phrase them in the following way, “It wouldn’t be unusual for someone in your circumstances to have thoughts of harming themselves. Have you had thoughts like that?” Patients with immediate, precise suicide plans and resources to carry out this plan should be immediately evaluated by psychiatric professionals.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Anxiety Anxiety is a subjective feeling of apprehension, tension, insecurity, and uneasiness, usually without a known specific cause. It may be anticipatory. It is assessed along a continuum as mild, moderate, or severe. Patients with life-limiting illness will experience various degrees of anxiety due to various issues such as their prognosis, mortality, financial concerns, uncontrolled pain and other symptoms, and feelings of loss of control.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Physical symptoms of anxiety include sweating, tachycardia, restlessness, agitation, trembling, chest pain, hyperventilation, tension, and insomnia. Cognitive symptoms include recurrent and persistent thoughts and difficulty concentrating. See Figure 17.25“ANXIETY.jpg” by Jayberries is licensed under CC BY-SA 3.0 for an illustration of anxiety. Benzodiazepines (i.e., lorazepam), may be prescribed to treat anxiety. However, the nurse should assess for adverse effects such as oversedation, falls, and delirium, especially in the frail elderly. Nonpharmacological interventions are crucial and include the following: - Maximizing symptom management to decrease stressors - Promoting the use of relaxation and guided imagery techniques, such as breathing exercises, progressive muscle relaxation, and the use of audiotapes - Referring for psychiatric counseling for those unable to cope with the experience of their illness - Facilitating spiritual support by contacting chaplains and clergy - Acknowledging patient fears and using open-ended questions and active listening with therapeutic communication - Identifying effective coping strategies the patient has used in the past, as well as teaching new coping skills such as as relaxation and guided imagery techniques - Providing concrete information to eliminate fear of the unknown - Encouraging the use of a stress diary that helps the patient understand the relationship between situations, thoughts, and feelingsThis work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Cognitive Changes Delirium is a common cognitive disorder in hospitals and palliative care settings. Delirium is an acute change in cognition and requires urgent management in inpatient care. Up to 90% of patients at the end of life will develop delirium in their final days and hours of life. Early detection of delirium can cause resolution if the cause is reversible.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Symptoms of delirium include agitation, confusion, hallucinations, or inappropriate behavior. It is important to obtain information from the caregiver to establish a mental status baseline. The most common cause of delirium at end of life is medication, followed by metabolic insufficiency due to organ failure.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Medications such as neuroleptics (i.e., haloperidol and chlorpromazine) or benzodiazepines may be prescribed. It is also important to remember that delirium can be related to opioid toxicity. It may be helpful to request the presence of family to reorient the patient, as well as provide nonpharmacological interventions such as massage, distraction, and relaxation techniques.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Read more about delirium in the “Cognitive Impairments” chapter. Fatigue Fatigue has been cited as the most disabling condition for patients receiving a variety of treatments in palliative care. Fatigue is defined as a distressing, persistent, subjective sense of physical, emotional, and/or cognitive tiredness or exhaustion that is not proportional to activity and interferes with usual functioning.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 See Figure 17.26“fatigue_sleep_head_old_honey-454317.jpg” by danielam is licensed under CC0 for an image of an older patient experiencing fatigue. The primary cause of fatigue is metabolic alteration related to chronic disease, but it can also be caused by anemia, infection, poor sleep quality, chronic pain, and medication side effects. Nonpharmacological interventions include energy conservation techniques. Pressure Injuries Patients at end of life are at risk for quickly developing pressure injuries, formerly referred to as pressure ulcers. Prevention is key and requires interventions such as promoting mobility, reducing moisture, and encouraging nutrition as appropriate. The Kennedy Terminal Ulcer is a type of pressure injury that some patients develop shortly before death resulting from multiorgan failure. It usually starts on the sacrum and is shaped like a pear, butterfly, or horseshoe. It is red, yellow, black, or purple in color with irregular borders and progresses quickly. For example, the injury may be identified by a nurse at the end of a shift who says, “That injury was not present when I assessed the patient this morning.”This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Read more about assessing, preventing, and treating pressure injuries in the “Integumentary” chapter. Seizures Seizures are sudden, abnormal, excessive electrical impulses in the brain that alter neurological functions such as motor, autonomic, behavioral, and cognitive function. A seizure can be caused by infection, trauma, brain injury, brain tumors, side effects of medications, metabolic imbalances, drug toxicities, and withdrawal from medications.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Seizures can have gradual or acute onset and include symptoms such as mental status changes, motor movement changes, and sensory changes. Treatment is focused on prevention and limiting trauma that occur during the seizure. Medications may be prescribed such as phenytoin, phenobarbital, benzodiazepines, or levetiracetam.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Sleep Disturbances Sleep disturbances affect quality of life and can cause much suffering. It can be caused by poor pain and symptom management, as well as environmental disturbances. Nurses can promote improved sleep for inpatients by creating a quiet, calm environment, promoting sleep routines, and advocating for periods of uninterrupted rest without disruptions by the health care team. Read more about promoting good sleep in the “Sleep and Rest” chapter. 17.5 Nursing Care During the Final Hours of Life Open Resources for Nursing (Open RN) Recognizing approaching death allows the patient, family members, and interdisciplinary team to prepare for the actively dying phase. The nurse has two primary responsibilities at this time: providing symptom management and preparing the family for what to expect as death is approaching. Nurses also have additional responsibilities regarding organ donation, postmortem care, and facilitating arrangements. It is essential for nurses to ensure that patients and their family members have access to the interdisciplinary team in the final days before death. Developmentally appropriate education should be provided to the patient, family, and/or other caregivers about what to expect during the final hours of life, as well as immediately following the patient’s death. Early access to hospice support should be facilitated whenever possible to optimize care outcomes for the patient and the family.American Association of Colleges of Nursing. (2021). End-of-life-care (ELNEC). https://www.aacnnursing.org/ELNEC Nurses have a responsibility to carry out and respect the patient’s wishes to the extent they can. Each individual patient is different, and what works best for one patient might not work well for another. Dying is a multifaceted process that is unique to every patient. Providing a “good death” for patients means respecting their preferences and offering support for them and their family. The nurse assumes multiple roles of advocate, professional caregiver, educator, and supporter and is frequently the one to facilitate a dignified death no matter the setting where death occurs. Nurses must be comfortable in “providing presence” and “bearing witness” with dying patients and their families. Rhythms of care (i.e., vital signs and routine assessments) often change during these final hours; be aware if these actions provide comfort or are burdens causing discomfort.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Avoid overwhelming the family with too much medical jargon. Provide simple answers in accordance with the patient’s and family’s understanding and readiness for responses. Family members may be tired, emotional, and have difficulty concentrating. Because they may be in crisis and unable to retain much information, you may need to answer the same questions or provide the same information repeatedly.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 It is helpful to provide family members written resources about what to expect. A commonly used resource in hospice care that can be very comforting for family members is Gone From My Sight: The Dying Experience. It is an inexpensive resource available to order online if it is not available at your facility. There is no typical death. Each person dies in their own way, at their own time, with their own beliefs and values, and with unique relationships with family, friends, and significant others. Many people experience similar psychological and emotional responses during this time, such as fear of the dying process, fear of abandonment, fear of the unknown, nearing death awareness, and withdrawal. The nurse is essential in addressing patient’s fears and managing their symptoms according to their preferences. Managing Common Symptoms During the Dying Process Most patients experience the dying process as a natural slowing down of physical and mental processes. Two roads to death have often been described. One road involves sedation and lethargy leading to a comatose state and death. Another road involves confusion, restlessness, muscle jerks, seizures, and death.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Pain and Dyspnea During the final hours of life, changes in level of consciousness can make assessment and management of pain challenging. Consider behavioral cues such as grimacing and posturing, as well as previous pain issues. Some patients also demonstrate signs of increased dyspnea, commonly referred to as “air hunger,” with labored and increased work of breathing. Pain pumps may be used to relieve severe pain, especially cancer-related pain. Medication can also be administered orally, even up to the last hours of life, for pain and dyspnea.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 For example, Roxanol is a highly concentrated solution of morphine sulfate that can be administered sublingually for pain and/or air hunger. The typical dosage is 20 mg/mL. Morphine not only relieves pain, but also is used to relax respiratory muscles and improve air exchange to relieve air hunger. However, the nurse should always balance providing analgesia with the patient’s goal for maintaining alertness. Principle of Double Effect Nurses and family members may be hesitant to administer morphine in the last few hours of life, fearing that it may hasten death, yet also not wanting to see the patient suffer. The American Nurses Association and the Palliative Care Nurses Association support the nurse in this dilemma that is often referred to as the Rule of Double Effect. If the intent is good (i.e., relief of pain and suffering), then the act is morally justifiable even if it causes an unintended result of hastening death. Thus, the nurse should provide pain relief, without fear of sedation or respiratory depression that typically limits the administration of opioids, in the final days and hours of a patient’s life.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Terminal Secretions Terminal secretions, commonly known as the “death rattle,” can be a distressing and frightening symptom for family members and those involved in the patient’s care. Terminal secretions are usually observed 3-23 hours before death. Anticholinergic medications, such as atropine or scopolamine, can be used to dry the secretions. It is also helpful to reposition the patient on their side, if feasible. Suctioning is not recommended because it is not typically effective for these types of secretions and can cause increased agitation and distress in the patient. Family members caring for patients at home under hospice care should be warned about this phenomenon and instructed about potential treatment.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 View a supplementary video (11 minutes) on Lessons from a hospice nurse: Alia Indrawan at TEDxUbud.TedX Talks. (2012, June 22). Lessons from a hospice nurse: Alia Indrawan at TEDxUbud. [Video]. YouTube. All rights reserved. https://youtu.be/2xs8qmk0OPc Phases of Dying There are typically four phases that a person progresses through when dying. These phases include actively dying, transitioning, imminent death, and death. Actively Dying A patient in this phase will experience symptoms such as pain, dyspnea, fatigue, cough, incontinence, nausea and vomiting, depression, anxiety, and seizures. Treatments during this phase are focused on symptom management and emotional support to both the patient and the family. Read more about symptom management in the “Palliative Care Management” section of this chapter. Educating the family and patient on what to expect is essential. Include written materials and progressive education as the patient’s condition changes. It is often helpful to provide guidance to the family in anticipation of upcoming phases of dying. Transitioning This is the phase between actively dying and imminent death where the patient withdraws physically. The patient begins to demonstrate decreased interest in activities of life with less frequent interactions with others and often has hallucinations. Other signs of this phase include hypoxia and acidosis. It is important for the nurse to keep the patient’s environment as comfortable as possible, such as keeping lights low and minimizing alarms and other noises. Imminent Death will occur at any point during the imminent phase due to multisystem organ failure. This phase usually occurs within 24 hours before death with common, recognizable signs. See Table 17.5 for typical signs that occur during this stage and indicate that death is imminent. Table 17.5 Typical Signs as Death Becomes Imminent \| System \| Signs \| \|---\|---\| \| Cardiovascular \| Cool, clammy skin; mottled extremities; rapid or irregular pulse \| \| Musculoskeletal \| Inability to ambulate, move, or turn in bed \| \| Neurological \| Confusion, restlessness, increased lethargy, hallucinations \| \| Respiratory \| Increased respiratory rate, inability to clear secretions, Cheyenne-Stokes respirations, noisy breathing (i.e., terminal secretions) \| \| Urinary \| Decreased or dark urine output \| During this stage, the family often requires additional support from the nurse as death becomes more of a reality. Vital signs are usually no longer assessed because they do not provide a benefit for the patient. The nurse should offer support by encouraging reminiscence, calming music, touch, light massage, presence, and prayer (according to family preferences) as the patient begins their transition. The dying process is variable for each individual. Families often ask for a definitive time frame when death will occur. Although these signs that indicate progression within 24 hours, a specific time line cannot be predicted. Some patients seem to instinctively know when death will occur. Be aware of religious practices and beliefs that are sacred to the patient and/or their family members at this time. Provide spiritual comfort through presence and prayer (based on patient preferences and the nurse’s comfort level). Call the agency chaplain and/or the patient’s clergy as indicted. (Read more about chaplains in the “Spirituality” chapter.) Encourage family members to bring in favorite hymns, scriptures, or symbols (i.e., a rosary) so the patient can experience these spiritual comforts through different senses (hearing, seeing, touching).This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Consider coaching family members about the five tasks that may serve as parting words with their loved one: - To ask forgiveness - To forgive - To say “Thank you” - To say “I love you” - To say “Goodbye” Read more about parting tasks in the book by Ira Byock, M.D. titled The Four Things That Matter Most.https://irabyock.org/books/the-four-things-that-matter-most/ Death Vigil by Family Members Family members have historically desired to be at the patient’s bedside during the days to hours before death. See Figure 17.27“Life_of_George_Washington_LCCN2002719381.jpg” by Popular Graphic Arts is in the Public Domain for artwork depicting the death vigil by family members when George Washington died. Family members have common fears, such as the following: - The patient being alone when they die - Not knowing how to react or what to do - Watching the patient suffer - Not knowing if the patient has died - Giving the “last dose” of medication at home and inadvertently causing death It is important for the nurse to address family members’ fears proactively and provide education and support. Death and Postmortem Care Clinical death occurs when blood circulation ceases, the heart stops beating, and respirations stop. Within 4-6 minutes of clinical death, CPR can be performed to attempt resuscitation. However, because most patients receiving palliative or hospice care have Do Not Resuscitate (DNR) orders in place, CPR is not performed. After this time window, brain cells die from lack of oxygen, followed by death of cells in other organs. This is called biological death. Rigor mortis, stiffening of muscles, will begin to set in several hours following death and be at its peak 12-18 hours following death. Rigor mortis disappears 48 hours following death. The nurse should listen to the apical heartbeat for one full minute to ensure and document that death has occurred. When a resident or patient passes away, the nurse should perform and document a final nursing assessment that includes the following: - Date and time of the assessment - Patient name - Time of physician contact - Individuals present at time of death (i.e., family members, friends) - Lack of response to stimuli - Absence of apical pulse - Arrangement for transport to the morgue or funeral home Care following a patient’s death requires sensitivity for the dignity of the deceased, as well as time for the care of family members. Following the death pronouncement, family members may feel numb and confused about what to do next. In a quiet and private place, explain the process for care of the body immediately following death.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 Following death, medical supplies and equipment tubes should be removed unless a coroner must approve of such measures. The goal is to provide a more personal closure experience for the family, leaving them memories of the deceased as a loved one rather than as a patient. Bathing, dressing, and positioning the body show respect and provide dignity for the patient and family. Position the body in proper alignment and place dentures in the mouth. Place dressings on leaking wounds and apply incontinence products as needed. Remember to honor cultural practices regarding care of the body after death and who should provide that care.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 The nurse should continue to provide support for the family and offer assistance as needed, such as contacting other family members to inform them of the death. Some family members may want to take pictures, comb their loved one’s hair, wash their face, hold their hand, kiss them, or crawl into bed and hold them. Support families in their various ways of saying goodbye. Ask if the family completed preplanning for burial or cremation, but do not rush their final visit. In some cases, families will not have had time for making prearrangements. If they have made prearrangements, contact the funeral home. Be aware of county and agency policies that require notification of the local coroner prior to calling the funeral home.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 When burial is chosen, the body will be embalmed, which is removing blood from the body and replacing it with an embalming solution that contains formaldehyde and other chemicals. The embalming process temporarily preserves the body to be shown at a funeral or memorial service. Cremation is the process of using heat to reduce the body to ashes that can be placed in a container called an urn. In some cultures, cremation is an ancient tradition. Depending on the family’s cultural beliefs and preferences, the ashes may be buried, placed in a mausoleum, or kept at home in an urn. See Figure 17.28“Memorial_Garden,_the_Museum_of_the_US_Air_Forces,_Dayton,_Ohio._(41410862864).jpg” by Roland Turner is licensed under CC BY-SA 2.0 for an image of a burial in a memorial garden. In hospital settings, there may be a sense of urgency to get the room cleared as soon as possible so that another patient can be admitted. However, the nurse should advocate for the patient and make arrangements so the family does not feel rushed.This work is a derivative of Nursing Care at the End of Life by Lowey and is licensed under CC BY-NC-SA 4.0 After the family has said their goodbyes and left the room, it is the nurses responsibility to ensure identification tags are applied to the body and the patient is moved to the morgue. Organ Donation If the patient is an organ or tissue donor, follow procedures as planned and in accordance with state and care setting guidelines, policies, and procedures. The patient’s drivers license may have information about their organ donation wishes. Federal law and Medicare regulations mandate that hospitals give surviving family members the chance to authorize donation of their loved one’s organs and tissues. Many family members feel consolation in helping others through organ donation despite their own loss. There is no cost for organ or tissue donation. 17.6 Applying the Nursing Process at End of Life Open Resources for Nursing (Open RN) This section will summarize the steps of the nursing process when caring for a patient who is actively dying and their family members. Assessment Assessments are generally limited for those patients at the end of life with the overall treatment goal of providing comfort. The goal in any performed assessment is to help ease the patient’s discomfort as the body begins to fail and facilitate a peaceful transition. If end-of-life care is occurring within the hospital setting, the nurse may need to remind members of the care team that “normal” care routines are not required. This may include collection of vital signs, intake and outputs, laboratory blood draws, and full physical assessment. It can feel challenging to switch modes of care in the inpatient setting where so many of our actions are focused on intervention and restoring a patient to health. However it is important to remember that our interventions take a different, but no less important, form. Providing comfort care at the end of life is one of the most important interventions a nurse can do to help ease patient and family suffering. Subjective Assessment Many individuals at the end of life may be nonverbal. Some may experience times of reminiscence as they progress toward death. It is important for the nurse to inform the family that communication can be quite variable as the patient progresses toward death, but the sense of hearing may still be intact. Family members and friends should be encouraged to share their thoughts and feelings with the patient, taking time to relate stories of comfort and feelings to the patient. This can be a therapeutic exchange for both the patient and the family. Objective Assessment Physical assessments should be limited and focused on providing patient comfort and creating a supportive environment for a therapeutic transition. Signs of pain such as grimacing, moaning, furrowing brow, and physical guarding should be noted and addressed. Many patients may experience increased respirations, labored breathing, and increased secretions that produce an audible respiratory “rattle.” The patient typically has a significant decline in circulation as they progress towards death, evidenced by cool and clammy skin, mottled extremities, and diminished pulses. The nurse should continue to monitor for signs of skin breakdown and urinary retention. Notify the provider of unexpected findings on assessment, such as severe pain not relieved by pain management protocol, acute labored breathing, terminal secretions, or urinary retention resulting in bladder distention. Diagnosis As the patient progresses toward death, diagnosis statements are focused on provision of comfort for the patient. Identification of acute pain and ineffective breathing are areas that typically become priority as patients near their final transition. Additionally, attention to family coping and caregiver role strain remain areas of focus as the nurse assists family members in coping with the dying process. When planning care, review a nursing care planning source for current NANDA-I approved nursing diagnoses and evidence-based nursing interventions. See Table 17.6 for the definition and defining characteristics regarding the NANDA-I diagnosis Death Anxiety.Herdman, T., & Kamitsuru, S. (2017). NANDA international nursing diagnoses: Definitions & classification 2018-2020 (11th ed.). Thieme Publishers, pp. 335, 339-341. Table 17.6 NANDA-I Nursing Diagnoses Death AnxietyHerdman, T., & Kamitsuru, S. (2017). NANDA international nursing diagnoses: Definitions & classification 2018-2020 (11th ed.). Thieme Publishers, pp. 335, 339-341. \| NANDA-I Diagnosis \| Definition \| Defining Characteristics \| \|---\|---\|---\| \| Death Anxiety \| Vague, uneasy feeling of discomfort or dread generated by perceptions of a real or imagined threat to one’s existence. \| \| Outcomes An overall goal for a patient who is actively dying is, The patient will experience dignified life closure as evidenced by: - Expression of readiness for death - Resolution of important issues - Sharing of feelings about dying - Discussion regarding spiritual concernsAckley, B., Ladwig, G., Makic, M. B., Martinez-Kratz, M., & Zanotti, M. (2020). Nursing diagnosis handbook: An evidence-based guide to planning care (12th ed.). Elsevier, pp. 144-147, 434-444. An example of a SMART outcome for a patient actively dying is, “The patient will express their fears associated with dying by the end of the shift.”Ackley, B., Ladwig, G., Makic, M. B., Martinez-Kratz, M., & Zanotti, M. (2020). Nursing diagnosis handbook: An evidence-based guide to planning care (12th ed.). Elsevier, pp. 144-147, 434-444. Nursing goals for care focus on the provision of comfort. For example, a common nursing goal is, “The patient will experience adequate pain management based on their expressed goals for pain relief and alertness.” Planning and Implementing Interventions Many patients require pain medications to assist with a therapeutic transition as they near death. These medications often include morphine and lorazepam to help ease pain, dyspnea, and anxiety. It is important for the nurse to be conscientious of the appropriateness of the medication’s route of administration, recognizing that patient condition can change rapidly. Concentrated oral solutions are absorbed through the buccal membranes, but if pain management needs are high, it may be necessary to contact the provider regarding a subcutaneous pump. Many patients in the imminent phase have terminal secretions so anticholinergic medications such as atropine or scopolamine may be administered. See the following box for a summary of other nursing interventions in the last days and hours of a patient’s life. Interventions in the Last Days and Hours of LifeAckley, B., Ladwig, G., Makic, M. B., Martinez-Kratz, M., & Zanotti, M. (2020). Nursing diagnosis handbook: An evidence-based guide to planning care (12th ed.). Elsevier, pp. 144-147, 434-444. - Honor the patient’s preferences for end-of-life care. - Be respectful of the environment. Physical assessment and cares should be provided with the utmost respect and attention to comfort. Shielding the patient from harsh light or loud voices is encouraged to help provide a respectful environment. - Reinforce the steps of the dying process so that family remains cognizant of what to expect. Although this can feel redundant, this conversation and anticipatory planning are very helpful due to the emotional nature of the situation and challenges that they may experience with information retention. - Be present and attentive. Use active empathetic listening. - Encourage the family to create a quiet and comfortable environment. - Assess the patient for pain and provide pain relief measures based on their preferences. - Assess the patient for fears related to death. - Assist the patient with life review and reminiscence. - Provide music of the patient’s choosing. - Provide social support for families and guide them through end-of-life issues. - Recognize the spiritual needs of the patient and their family members. Support religious beliefs, rituals, and prayer. - Encourage family members to be physically close to their loved one and give them permission to touch them. - When death occurs, allow appropriate time for closure. Provide information regarding the next steps of physical care and transporting the patient. Evaluation It is always important to evaluate the effectiveness of interventions based on the outcome criteria established for each patient. The nurse should closely monitor for escalating signs of patient discomfort that is not managed by the current treatment plan. It is helpful to educate the family regarding whom to contact if additional concerns arise. 17.7 Putting It All Together Patient Scenario Mr. Yun is a 34-year-old man presenting to his physician’s office for a follow-up visit. The patient recently experienced the loss of his wife in a motor vehicle accident and reports, “I have problems concentrating and I can’t sleep at night.” The patient chart indicates he has lost 15 pounds since his previous visit last month. He reports, “I have a hard time getting out of bed in the morning.” On further questioning, he admits drinking 5-6 alcoholic beverages every night to “numb myself.” Applying the Nursing Process Assessment: The nurse notes that Mr. Yun is experiencing difficulty concentrating, difficulty sleeping, and unintentional weight loss of greater than 15 pounds since his wife passed away. He self-reports drinking 5-6 alcoholic beverages every night to “numb myself.” Based on the assessment information that has been gathered, the following nursing care plan is created for Mr. Yun: Nursing Diagnosis: Ineffective Coping related to inability to deal with a situation as manifested by unintended weight loss, difficulty concentrating, difficulty sleeping, and drinking 5-6 alcoholic beverages daily to “numb myself.” Overall Goal: The patient will demonstrate improved coping. SMART Expected Outcome: Mr. Yun will verbalize three positive coping behaviors by the end of the teaching session. Planning and Implementing Nursing Interventions: The nurse will identify the patient’s personal resources and relationships. The nurse will use empathetic communication to establish a relationship with the patient. The nurse will encourage the patient to participate in activities that bring personal satisfaction to the patient. The nurse will provide education regarding the value of exercise, meditation, prayer, etc., to enhance individual coping. The nurse will provide the patient with education regarding the support resources available within the patient’s community. Sample Documentation Mr. Yun exhibits signs of ineffective coping in relation to his inability to deal with the loss of his wife. He reports difficulty concentrating, difficulty sleeping, and drinking 5-6 alcoholic beverages nightly to “numb myself.” He has had unintended weight loss of 15 pounds in the past month. Patient education was provided regarding positive coping skills. Mr. Yun verbalized three positive coping behaviors he plans to implement this month. Evaluation At the end of the teaching session, the nurse asks Mr. Yun what healthy coping strategies he plans to implement. Mr. Yun states he plans to go for daily walks, limit his alcohol intake to two servings a day, and listen to a meditation app that he enjoys every evening before bed. He plans to contact a local church to attend a support group for widowers. The SMART outcome was “met.” 17.8 Learning Activities Open Resources for Nursing (Open RN) Learning Activities (Answers to “Learning Activities” can be found in the “Answer Key” at the end of the book. Answers to interactive activity elements will be provided within the element as immediate feedback.) The patient’s condition has declined significantly over the past week; she is actively dying. Over the last 24 hours, Mrs. Lyn has declined rapidly and is now unresponsive but appears to be resting comfortably. You enter the patient’s room and find Mr. Lyn weeping at the patient’s bedside. - What actions would you take to comfort Mr. Lyn? - Mrs. Lyn develops labored breathing. What medication is helpful to administer to treat dyspnea at end of life? - Mrs. Lyn’s breathing becomes less labored with medication, but her respiratory rate becomes irregular. Mr. Lyn tells the nurse, “My daughter lives six hours away and would like to be here when the time comes. How much longer does she have to live?” What is the nurse’s best response? - The daughter arrives and seems hesitant to talk to or touch her mother. What tasks can the nurse coach family members to do at the end of a patient’s life? - Mrs. Lyn dies the following evening. What postmortem care should the nurse provide? Scenario B Terry, 42 year-old male patient, was recently diagnosed with advanced colon cancer and underwent a colon resection a few days ago. While changing his colostomy bag, he comments to the nurse, “I still can’t believe this is happening to me.” - According to Kubler-Ross’ theory of grief/loss, what stage of grief is Terry currently experiencing? - The nurse responds, “This is a difficult time for you.” Terry replies, “Yes it is. My parents want me to do every kind of experimental treatment possible, but I just want to live my life until the time comes.” The nurse asks, “You have some tough decisions to make. Has anyone talked to you about palliative care yet?” Terry asks, “I’ve never heard of palliative care. What is it?” How would you explain palliative care to him? - Terry states, “I don’t want my parents telling my doctor what to do. It is my decision.” The nurse asks, “Do you have any advance directives in place?” Terry responds, “What are advance directives?” How would you explain advance directives to Terry? - The nurse identifies “Grieving related to anticipatory loss as evidenced by disbelief and feeling of shock” as a nursing diagnosis for Terry. Identify a SMART outcome. - The nurse plans interventions to enhance Terry’s coping. List sample nursing interventions that may help Terry to cope with this new diagnosis. An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=1625#h5p-73 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=1625#h5p-37 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=1625#h5p-38 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=1625#h5p-87 XVII Glossary Open Resources for Nursing (Open RN) Acute grief: Grief that begins immediately after the death of a loved one and includes the separation response and response to stress. Advance directives: Legal documents that direct care when the patient can no longer speak from themselves, including the living will and the health care power of attorney. Anorexia: Loss of appetite or loss of desire to eat. Anticipatory grief: Grief before a loss, associated with diagnosis of an acute, chronic, and/or terminal illness experienced by the patient, family, and caregivers. Examples of anticipatory grief include actual or fear of potential loss or health, independence, body part, financial stability, choice, or mental function. Bereavement period: The time it takes for the mourner to feel the pain of the loss, mourn, grieve, and adjust to the world without the presence of the deceased. Burnout: A caregiver’s diminished caring and cynicism that can be triggered by workplace demands, lack of resources to do work professionally and safely, interpersonal relationship stressors, or work policies that can lead to diminished caring and cynicism. Burnout may be manifested physically and psychologically with a loss of motivation. Cachexia: Wasting of muscle and adipose tissue due to lack of nutrition. Cardiopulmonary resuscitation (CPR): Emergency treatment initiated when a patient’s breathing stops or their heart stops beating. It may involve chest compressions and mouth-to-mouth breathing, electric shocks to restart the heart, breathing tubes to open the airway, or cardiac medications. Comfort care: Care that occurs when the patient’s and medical team’s goals shift from curative interventions to symptom control, pain relief, and quality of life. Compassion fatigue: A state of chronic and continuous self-sacrifice and/or prolonged exposure to difficult situations that affect a health care professional’s physical, emotional, and spiritual well-being. Complicated grief: Chronic grief, delayed grief, exaggerated grief, and masked grief are types of complicated grief. Disenfranchised grief: Any loss that is not validated or recognized. Do-not-resuscitate (DNR) order: A medical order that instructs health care professionals not to perform cardiopulmonary resuscitation (CPR) if a patient’s breathing stops or if the patient’s heart stops beating. Fading away: A transition that families make when they realize their seriously ill family member is dying. Grief: The emotional response to a loss, defined as the individualized and personalized feelings and responses that an individual makes to real, perceived, or anticipated loss. Health care power of attorney: A legal document that identifies a trusted individual to serve as a decision maker for health issues when the patient is no longer able to speak for themselves. Hospice care: A type of palliative care that addresses care for patients who are terminally ill when a health care provider has determined they are expected to live six months or less. Living will: A legal document that describes the patient’s wishes if they are no longer able to speak for themselves due to injury, illness, or a persistent vegetative state. The living will addresses issues like ventilator support, feeding tube placement, cardiopulmonary resuscitation, and intubation. Loss: The absence of a possession or future possession with the response of grief and the expression of mourning. Mourning: The outward, social expression of loss. Individuals outwardly express loss based on their cultural norms, customs, and practices, including rituals and traditions. Normal grief: The common feelings, behaviors, and reactions to loss. Palliative care: Patient and family-centered care that optimizes quality of life by anticipating, preventing, and treating suffering. Palliative care occurs throughout the continuum of care and involves the interdisciplinary team collaboratively addressing physical, intellectual, emotional, social, and spiritual needs and facilitating patient autonomy, access to information, and choice. Spirituality XVIII 18.1 Spirituality Introduction Open Resources for Nursing (Open RN) Learning Objectives - Demonstrate principles of holistic care by incorporating cultural, religious, and spiritual influences on patient health - Explain the interconnection between spirituality and religious concepts as they relate to health and spiritually sensitive nursing care - Describe methods to assess the spiritual and religious preferences, strengths, concerns, or distress of clients and plan appropriate nursing care Spirituality includes a sense of connection to something bigger than oneself and typically involves a search for meaning and purpose in life. People may describe a spiritual experience as sacred or transcendent or simply feel a deep sense of aliveness and interconnectedness. Some people’s spiritual life is linked to a religious association with a church, temple, mosque, or synagogue, whereas others pray and find comfort in a personal relationship with God or a higher power and still others find meaning through their connections to nature or art. A person’s definition of spirituality and sense of purpose often change throughout one’s lifetime as it evolves based on personal experiences and relationships.Delagran, L. (n.d.). What is spirituality? University of Minnesota. https://www.takingcharge.csh.umn.edu/what-spirituality Over the past decade, research has demonstrated the importance of spirituality in health care. Spiritual distress is very common in patients and their family members experiencing serious illness, injury, or death, and nurses are on the front lines as they assist these individuals to cope. Addressing a patient’s spirituality and providing spiritual care have been shown to improve patients’ health and quality of life, including how they experience pain, cope with stress and suffering associated with serious illness, and approach end of life.Pilger, C., Molzahn, A. E., de Oliveira, M. P., & Kusumota, L. (2016). The relationship of the spiritual and religious dimensions with quality of life and health of patients with chronic kidney disease: An integrative literature review. Nephrology Nursing Journal, 43(5), 411–426. https://pubmed.ncbi.nlm.nih.gov/30550069/,Puchalski, C., Jafari, N., Buller, H., Haythorn, T., Jacobs, C., & Ferrell, B. (2020). Interprofessional spiritual care education curriculum: A milestone toward the provision of spiritual care. Journal of Palliative Medicine, 23(6), 777–784. https://doi.org/10.1089/jpm.2019.0375 Consensus-driven recommendations define a spiritual care model where all clinicians address spiritual issues and work with trained chaplains who are spiritual care specialists.Pilger, C., Molzahn, A. E., de Oliveira, M. P., & Kusumota, L. (2016). The relationship of the spiritual and religious dimensions with quality of life and health of patients with chronic kidney disease: An integrative literature review. Nephrology Nursing Journal, 43(5), 411–426. https://pubmed.ncbi.nlm.nih.gov/30550069/,Puchalski, C., Jafari, N., Buller, H., Haythorn, T., Jacobs, C., & Ferrell, B. (2020). Interprofessional spiritual care education curriculum: A milestone toward the provision of spiritual care. Journal of Palliative Medicine, 23(6), 777–784. https://doi.org/10.1089/jpm.2019.0375 By therapeutically using presence, unconditional acceptance, and compassion, nurses often provide spiritual care and help patients find hope and meaning in their life experiences.Erickson, H. (2007). Philosophy and theory of holism. The Nursing Clinics of North American, 42(2).https://doi.org/10.1016/j.cnur.2007.03.001 The Interprofessional Spiritual Care Education Curriculum (ISPEC), developed by George Washington University for health care professionals, is an education initiative to improve spiritual care for seriously ill patients in the United States and internationally. This chapter will introduce concepts included in the ISPEC curriculum, review religious beliefs and practices of various world religions, and discuss therapeutic interventions that nurses can use to promote patients’ and their own spiritual well-being. Read more about professional development opportunities regarding spiritual health using the Interprofessional Spiritual Care Education Curriculum (ISPEC) offered by George Washington University Institute for Spirituality and Health. Explore more information about spirituality using free online resources provided by the University of Minnesota’s Earl E. Bakken Center for Spirituality and Healing. 18.2 Basic Concepts Open Resources for Nursing (Open RN) Spiritual Distress When patients are initially diagnosed with an illness or experience a serious injury, they often grapple with the existential question, “Why is this happening to me?” This question is often a sign of spiritual distress. Spiritual distress is defined by NANDA-I as, “A state of suffering related to the inability to experience meaning in life through connections with self, others, the world, or a superior being.”Herdman, T. H. & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York, pp. 365, 372-377. Nurses can help relieve this suffering by therapeutically responding to patients’ signs of spiritual distress and advocating for their spiritual needs throughout their health care experience. Spirituality Provision 1 of the ANA Code of Ethics states, “The nurse practices with compassion and respect for the inherent dignity, worth, and unique attributes of every person” and “optimal nursing care enables the patient to live with as much physical, emotional, social, and religious or spiritual well-being as possible and reflects the patient’s own values.”American Nurses Association. (2015). Code of ethics for nurses with interpretive statements. American Nurses Association. https://www.nursingworld.org/practice-policy/nursing-excellence/ethics/code-of-ethics-for-nurses/coe-view-only/ Spiritual well-being is a pattern of experiencing and integrating meaning and purpose in life through connectedness with self, others, art, music, literature, nature, and/or a power greater than oneself.Herdman, T. H. & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York, pp. 365, 372-377. Spirituality is defined by the Interprofessional Spiritual Care Education Curriculum (ISPEC) as, “A dynamic and intrinsic aspect of humanity through which persons seek ultimate meaning, purpose, and transcendence and experience relationship to self, family, others, community, society, nature, and the significant or sacred.”Puchalski, C. M., Vitillo, R., Hull, S. K., & Reller, N. (2014). Improving the spiritual dimension of whole person care: Reaching national and international consensus. Journal of Palliative Medicine, 17(6), 642–656. https://doi.org/10.1089/jpm.2014.9427 Spiritual needs and spirituality are often mistakenly equated with religion, but spirituality is a broader concept. Elements of spirituality include faith, meaning, love, belonging, forgiveness, and connectedness.Rudolfsson, G., Berggren, I., & da Silva, A. B. (2014). Experiences of spirituality and spiritual values in the context of nursing – An integrative review. The Open Nursing Journal, 8, 64–70. https://dx.doi.org/10.2174%2F1874434601408010064 Spirituality and spiritual values in the context of nursing are closely intertwined with the concept of caring.Rudolfsson, G., Berggren, I., & da Silva, A. B. (2014). Experiences of spirituality and spiritual values in the context of nursing – An integrative review. The Open Nursing Journal, 8, 64–70. https://doi.org/10.2174/1874434601408010064 See Figure 18.1“960_720.jpg” by Activedia is licensed under CC0 for an illustration of spirituality. An integrative review of nursing research and resources was completed in 2014 to describe the impact of spirituality and spiritual support in nursing.Rudolfsson, G., Berggren, I., & da Silva, A. B. (2014). Experiences of spirituality and spiritual values in the context of nursing – An integrative review. The Open Nursing Journal, 8, 64–70. https://dx.doi.org/10.2174%2F1874434601408010064 See the following box for discussion of findings from this integrative review. Integrative Review of Spirituality in NursingRudolfsson, G., Berggren, I., & da Silva, A. B. (2014). Experiences of spirituality and spiritual values in the context of nursing – An integrative review. The Open Nursing Journal, 8, 64–70. https://dx.doi.org/10.2174%2F1874434601408010064 An integrative review of nursing literature selected 26 articles published between 1999 and 2013 to describe the experiences of spirituality and the positive impact of spiritual support in nursing literature.Rudolfsson, G., Berggren, I., & da Silva, A. B. (2014). Experiences of spirituality and spiritual values in the context of nursing – An integrative review. The Open Nursing Journal, 8, 64–70. https://doi.org/10.2174/1874434601408010064 Spirituality was described as the integration of body, mind, and spirit into a harmonious whole (often referred to as holistic care). Spirituality was associated with the development of inner strength, looking into one’s own soul, believing there is more to life than worldly affairs, and trying to understand who we are and why we are on this earth. Transcendence was described as an understanding of being part of a greater picture or of something greater than oneself, such as the awe one can experience when walking in nature. It was also expressed as a search for the sacred through subjective feelings, thoughts, and behaviors. Spirituality was found to have a positive effect on patients’ health and promoted recovery by viewing life from different perspectives and looking beyond one’s own anxiety to develop an understanding of illness and change. Relationships and connectedness were also found to be powerful spiritual interventions that contributed to an individual’s spirituality. This included embracing, crying together, gift giving, having coffee together, and visiting each other. Laughter, happy thoughts, and the smiles of others were considered comforting. Being with others was described as a primary spiritual need, and conversation was unnecessary. Spirituality brought about the realization that the relationship with family and friends is important and involves finding a healthy balance in relationships among friends, family, society, and a higher power. Presence was the most influential element in positively influencing recovery. The presence of family and friends was a calming experience that brought forth comfort, peace, happiness, joy, acceptance, and hope. Nurses facilitate their patients’ search for meaning by enabling them to express personal beliefs, as well as by supporting them in taking part in their religious and cultural practices. Furthermore, nurses assess and meet their patients’ spiritual needs by using active listening when talking, asking questions, and picking up patient cues. Active listening requires nurses to be fully present, especially when patients appear depressed or upset. Nurses were found to use their own spirituality when helping patients achieve spiritual well-being. A desire to help others in need is an important part of spirituality, which is also described as discovering meaning and purpose in life and offering the gift of self to others. Helping others also brings a sense of self-worth, personal fulfilment, and satisfaction. Spiritual Assessment The Joint Commission requires that health care organizations provide a spiritual assessment when patients are admitted to a hospital. Spiritual assessment can include questions such as the following: - Who or what provides you with strength or hope? - How do you express your spirituality? - What spiritual needs can we advocate for you during this health care experience? In addition to performing a routine spiritual assessment on admission, nurses often notice other cues related to a patient’s spiritual distress or desire to enhance their spiritual well-being. When these cues are identified, spiritual care should be provided to relieve suffering and promote spiritual health. There are several nursing interventions that can be implemented, in addition to contacting the health care agency’s chaplain or the patient’s clergy member. See the “Applying the Nursing Process” section for a discussion of spiritual assessment tools and nursing interventions related to spiritual care. Many hospitals, nursing homes, assisted living facilities, and hospices employ professionally trained chaplains to assist with the spiritual, religious, and emotional needs of patients, family members, and staff. In these settings, chaplains support and encourage people of all religious faiths and cultures and customize their approach to each individual’s background, age, and medical condition. Chaplains can meet with any individual regardless of their belief, or lack of belief, in a higher power and can be very helpful in reducing anxiety and distress. A nurse can make a referral for a chaplain without a provider order. See Figure 18.2“Pastoral_Care.jpg” by WikiDavidUser is licensed under CC BY-SA 3.0 for an image of a hospital chaplain offering support to a patient. A chaplain assists patients and their family members to develop a spiritual view of their serious illness, injury, or death, which promotes coping and healing. A spiritual view of life and death includes elements such as the following: - - Suffering occurs at physical, mental, emotional, and spiritual levels. Sociocultural factors, religious beliefs, family values and dynamics, and other environmental factors affect a person’s response to suffering. - Hope is a desire or goal for a particular event or outcome. For example, some people may view dying as “hopeless” whereas a spiritual view can define hope as a “good death” when the patient dies peacefully according to the end-of-life preferences they previously expressed. Read more about the concept of a “good death” in the “Grief and Loss” chapter. - Mystery is knowing there is truth beyond understanding and explanation. - Peacemaking is the creation of a space for nurturing and healing. - Forgiveness is an internal process releasing intense emotions attached to past incidents. Self-forgiveness is essential to spiritual growth and healing. - Prayer is an expression of one’s spirituality through a personalized interaction or organized form of petitioning and worship. View these videos about spiritual care provided by chaplainsReligion & Ethics NewsWeekly. (2016, September 16). Spiritual healthcare. [Video]. YouTube. All rights reserved. https://youtu.be/97d1JMKTuk4,Northwell Health. (2015, December 14). A Day in the life of a chaplain. [Video]. YouTube. All rights reserved. https://youtu.be/0mERMJikQkg,Harvard T. H. Chan School of Public Health. (2017, August 29). Focus on the spiritual health can benefit patients–and doctors. [Video]. YouTube. https://youtu.be/mDfkhILODtE,Intermountain Healthcare. (2017, February 21). Chaplains and the role of spiritual care in healthcare. [Video]. YouTube. All rights reserved. https://youtu.be/l6n6chrQX0A: 18.3 Common Religions and Spiritual Practices Open Resources for Nursing (Open RN) It can be helpful for nurses to learn basic knowledge about common religions and religious practices as they support their patients’ beliefs. This section will review basic elements of common religions and religious practices. Religious Classifications For centuries, humankind has sought to understand and explain the “meaning of life.” Many philosophers believe this contemplation and the desire to understand our place in the universe are what differentiate humankind from other species. Religion, in one form or another, has been found in all human societies since human societies first appeared.This work is a derivative of Introduction to Sociology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/introduction-sociology-2e/pages/1-introduction-to-sociology Religion is a unified system of beliefs, values, and practices that a person holds sacred or considers to be spiritually significant. Some people associate religion with a place of worship (e.g., a synagogue or church), a practice (e.g., attending religious services, being baptized, or receiving communion), or a concept that guides one’s daily life (e.g., sin or kharma).This work is a derivative of Introduction to Sociology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/introduction-sociology-2e/pages/1-introduction-to-sociology See Figure 18.3“RELIGIONES.png” by Niusereset is licensed under CC BY-SA 3.0 for an illustration of symbols from many worldwide religions. The symbols are arranged in clockwise order starting at the 12:00 position: Judaism, Christianity, Islam, Bahá’í faith, Hinduism, Taoism, Buddhism, Sikhism, Rodnoveril, Celtic paganism, Heathenism, Semitic paganism, Wicca, Kemetism, Hellenic paganism, and Roman paganism. Religions Religions have been classified based on what or whom people worship (if anything). See Table 18.3 for a list of religious classifications.This work is a derivative of Introduction to Sociology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/introduction-sociology-2e/pages/1-introduction-to-sociology Table 18.3 Religious ClassificationsThis work is a derivative of Introduction to Sociology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/introduction-sociology-2e/pages/1-introduction-to-sociology \| Religious Classification \| What/Who Is Divine \| Example \| \|---\|---\|---\| \| Polytheism \| Multiple gods \| Belief systems of the ancient Greeks and Romans \| \| Monotheism \| Single god \| Judaism, Christianity, Islam \| \| Atheism \| Nothing \| Atheism \| \| Animism \| Nonhuman beings (animals, plants, natural world) \| Indigenous nature worship \| \| Totemism \| Human-natural being connection \| Native American beliefs \| Every culture has atheists who do not believe in a divine being or entity and agnostics who hold that ultimate reality (such as God) is unknowable. However, being a nonbeliever in a divine being does not mean the individual has no morality. For example, many Nobel Peace Prize winners have classified themselves as atheists or agnostics.This work is a derivative of Introduction to Sociology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/introduction-sociology-2e/pages/1-introduction-to-sociology Monotheism includes the religions of Judaism, Christianity, and Islam. People who practice Judaism are called Jews, people who practice Christianity are called Christians, and people who practice Islam are called Muslims. Jews, Christians, and Muslims believe in many of the same historical sacred stories, referred to by Christians as the “Old Testament.” In these shared sacred stories, it is believed that the son of God (a messiah) will return to save God’s followers. While Christians believe that the messiah has already appeared in the person of Jesus Christ, Jews and Muslims believe the messiah has yet to appear.This work is a derivative of Introduction to Sociology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/introduction-sociology-2e/pages/1-introduction-to-sociology The following subsections describe the general beliefs of five worldwide religions. However, as with all cultural beliefs, nurses should recognize an individual’s specific spiritual values, beliefs, and practices and not assume they believe in these elements based on the religion they profess. Judaism After their exodus from slavery in Egypt in the thirteenth century B.C., Jews became a nomadic society worshipping only one God. The Jewish covenant, a promise of a special relationship with Yahweh (God), is an important element of Judaism. The sacred text of Judaism is the Torah, which contains the same sacred stories in the first five books of the Christian’s Bible. Talmud is a collection of additional sacred Jewish oral interpretations of the Torah. Jews emphasize moral behavior and action in life.This work is a derivative of Introduction to Sociology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/introduction-sociology-2e/pages/1-introduction-to-sociology Jewish religious services are held in a synagogue. See Figure 18.4“star-of-david-458372_960_720.jpg” by hurk is licensed under CC0 for an image of the Torah and the Star of David, a traditional symbol of Judaism. Christianity Christianity began over 2,000 years ago in Palestine with the birth of a Jew named Jesus Christ. Jesus was a charismatic leader and believed by Christians to be the son of God, who taught his followers to treat others as one would like to be treated. The sacred text for Christians is the Bible that includes the “Old Testament” and the “New Testament.” The New Testament describes the life and teachings of Jesus.This work is a derivative of Introduction to Sociology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/introduction-sociology-2e/pages/1-introduction-to-sociology Christians attend religious services in a church or cathedral. See Figure 18.5“crucifix-4061847_960_720.jpg” by fz_3d is licensed under CC0 for an image of a sculpture depicting Jesus Christ crucified on a cross, a common symbol of Christianity. Christianity is broadly split into three branches: Catholic, Protestant, and Orthodox. The Catholic branch is governed by the Pope and many bishops around the world. There are many different denominations of Protestant faiths, such as Lutherans, Baptists, Presbyterians, Methodists, Seventh-Day Adventists, Pentecostals, and Mormons. Although all Christians believe the Bible is a sacred text, different denominations have variations in their sacred texts. For example, The Church of Jesus Christ of Latter-day Saints uses the Book of Mormon that they believe details other parts of Christian doctrine and Jesus’ life that aren’t included in the Bible. Similarly, the Catholic Bible includes a collection of stories that were part of the King James translation created in 1611 but are no longer included in Protestant versions of the Bible.This work is a derivative of Introduction to Sociology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/introduction-sociology-2e/pages/1-introduction-to-sociology Although monotheistic, Christians often describe God through three manifestations called the Holy Trinity: the father (God), the son (Jesus), and the Holy Spirit, similar to how water can be in different forms of ice, water, and gas. Another foundation to Christian faith is the Ten Commandments, a set of rules that includes acts considered sinful, such as theft, murder, and adultery.This work is a derivative of Introduction to Sociology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/introduction-sociology-2e/pages/1-introduction-to-sociology Islam Islam is monotheistic religion that follows the teaching of the prophet Muhammad, born in Mecca, Saudi Arabia, in 570 C.E. Muhammad is viewed as a prophet and a messenger of Allah (God), who is divine. The followers of Islam are called Muslims who attend religious services in mosques.This work is a derivative of Introduction to Sociology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/introduction-sociology-2e/pages/1-introduction-to-sociology See Figure 18.6“Amman_BW_29.JPG” by Berthold Werner is licensed under CC BY 3.0 for an image of a mosque. Islam means “peace” and “submission.” The sacred text for Muslims is the Qur’an (or Koran). Muslims are guided by five beliefs and practices, often called pillars of their faith, including believing that Allah is the only god and Muhammad is his prophet, participating in daily prayer, helping those in poverty, fasting as a spiritual practice, and participating in pilgrimage to the holy center of Mecca.This work is a derivative of Introduction to Sociology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/introduction-sociology-2e/pages/1-introduction-to-sociology Hinduism Hinduism originated in the Indus River Valley about 4,500 years ago in what is now modern-day northwest India and Pakistan. Hindus believe in a divine power that can manifest as different entities. Three main incarnations, Brahma, Vishnu, and Shiva, are sometimes compared to the Christian belief in the Holy Trinity.This work is a derivative of Introduction to Sociology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/introduction-sociology-2e/pages/1-introduction-to-sociology Multiple sacred texts, collectively called the Vedas, contain hymns and rituals from ancient India and are mostly written in Sanskrit. Hindus believe in a set of principles called dharma that refer to one’s duty in the world and correspond with “right” actions. Hindus also believe in karma, the notion that spiritual ramifications of one’s actions are balanced cyclically in this life or a future life (referred to as reincarnation).This work is a derivative of Introduction to Sociology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/introduction-sociology-2e/pages/1-introduction-to-sociology Most Hindus observe religious rituals at home. The rituals vary greatly among regions, villages, and individuals. See Figure 18.7“Shiva_Bangalore.jpg” by Kalyan Kumar is licensed under CC BY-SA 2.0 for a statue of Shiva in a yogic meditation. Yoga is a Hindu discipline that trains the body, mind, and consciousness for health, tranquility, and spiritual insight. Buddhism Buddhism is a philosophy founded by Siddhartha Gautama around 500 B.C.E. Siddhartha is believed to have given up a comfortable, upper-class life to follow one of poverty and spiritual devotion. At the age of thirty-five, he famously meditated under a sacred fig tree and vowed not to rise before he achieved enlightenment, called bodhi. After this experience, he became known as Buddha or “enlightened one.” Followers were drawn to Buddha’s teachings and the practice of meditation, and he later established a monastic order.This work is a derivative of Introduction to Sociology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/introduction-sociology-2e/pages/1-introduction-to-sociology Buddha’s teachings encourage Buddhists to lead a moral life by accepting the four Noble Truths: life is suffering, suffering arises from attachment to desires, suffering ceases when attachment to desires ceases, and freedom from suffering is possible by following the “middle way.” The concept of the “middle way” is central to Buddhist thinking and encourages people to live in the present, practice acceptance of others, and accept personal responsibility.This work is a derivative of Introduction to Sociology by OpenStax and is licensed under CC BY 4.0. Access for free at https://openstax.org/books/introduction-sociology-2e/pages/1-introduction-to-sociology See Figure 18.8“Four_Scenes_from_the_Life_of_the_Buddha_-_Enlightenment_-_Kushan_dynasty,_late_2nd_to_early_3rd_century_AD,_Gandhara,_schist_-_Freer_Gallery_of_Art_-_DSC05124.JPG” by Daderot is in the Public Domain, CC0 for a statue of the enlightenment of Buddha. Common Religious Beliefs and Practices Now that we have reviewed the basic beliefs of various world religions, this section describes common religious beliefs and practices that may impact nursing care. As always, customize nursing interventions according to each patient’s specific values, practices, and beliefs. Buddhist Patients - Buddhism places strong emphasis on “mindfulness,” so patients may request peace and quiet for the purpose of meditation, especially during crises. - Some Buddhists may express strong, culturally-based concerns about modesty (for instance, regarding treatment by someone of the opposite sex). - Some Buddhists are strictly vegetarian and refuse to consume any meat or animal by-product. For such patients, even medications that are produced using animals are likely to be problematic. See Figure 18.9“Vegetarian_meal_at_Buddhist_temple_(3810298969).jpg” by Andrea Schaffer is licensed under CC BY 2.0 for an image of a vegetarian meal in a Buddhist temple. - The importance of mindful awareness of all of life’s experience may affect patients’ or family members’ decisions about pain medications out of worry that analgesics may unduly cloud awareness. Nonpharmacological pain management options are often attractive. - Patients or families may pray or chant out loud repetitiously. This is often done quietly, and any noise concerns in a hospital can usually be negotiated easily. Families sometimes wish to place a picture of the Buddha in the patient’s room. - In end-of-life care, Buddhists may be very concerned about safeguarding their awareness/consciousness. Clarification of the patient’s wishes about the use of analgesics in the days and hours before death is strategically important for developing an ethical pain management plan. - As a patient approaches death, medical and nursing staff should minimize actions that might disturb their concentration or meditation in preparation for dying. Near the time of death, a Buddhist patient’s family may appear quite emotionally reserved and even keep their physical distance from the patient’s bed. This can be a custom for the purpose of supporting the patient’s desire to concentrate without distraction on the experience of dying. - After the patient has died, staff should try to keep the body as still as possible and avoid jostling during transport. Buddhism teaches that the body is not immediately devoid of the person’s spirit after death, so there is continued concern about disturbing the body. Such belief may also be an impediment to discussion of organ donation. - Families may request that after a patient has died the patient’s body be kept available to them for a number of hours for the purpose of religious rites. All such requests should be negotiated carefully, maximizing the opportunity for accommodation in recognition of the religious significance.Ehman, J. (2012, May 8). Religious diversity: Practical points for healthcare providers. Penn Medicine: Pastoral Care and Education. https://www.uphs.upenn.edu/pastoral/resed/diversity_points.html Catholic Patients - Sacraments and blessings by a Catholic priest can be viewed as highly important, especially before surgery or as a perceived risk of death. - If a patient is near death, there may be an urgent request for a Catholic priest to offer “Sacrament of the Sick” (which some Catholics may call “Last Rites”). Even if the sacrament has already been offered, there may still be a request for a priest to offer prayers and bless the patient. - All requests for the sacrament of baptism should be relayed to a Catholic priest. However, if an infant is likely to die before a priest can arrive, the infant may be baptized by any person with proper intent. The person would say, “[name of infant], I baptize you in the name of the Father, and of the Son, and of the Holy Spirit,” pouring a small amount of water over the infant’s head three times. Emergency baptisms are reported to the local Catholic parish priest. - Patients may request Holy Communion (Eucharist) prior to surgery. While a Catholic priest or Eucharistic Minister would typically offer such a patient only a tiny portion of a wafer, patients who are NPO (to have nothing by mouth) should have this request approved by the care team as medically safe. - Some patients may keep religious objects with them, such as a rosary (a loop of beads with a crucifix used for prayer), a scapula (a small cloth devotional pendant), or a religious medal. See Figure 18.10“SilverRosary.png” by Aprilwine is licensed under CC BY-SA 3.0 for an image of a rosary. If patients request that such an object remain with them during medical procedures, discuss the option of placing the object in a sealed bag that can be kept on or near the patient. If an object is metal and the patient is having a radiological procedure or test (like an MRI scan), ask the patient or family if they can bring in a nonmetal substitute. - Interruption of religious practices, such as regular attendance at Mass or special observance of special holy days, may be highly stressful to Catholic patients. Discuss contacting clergy and/or a hospital chaplain. - Patients may have moral questions about treatment decisions such as the withholding/withdrawing of life-sustaining treatment. A priest can offer authoritative guidance in specific situations. - Patients may request non-meat diets, especially during the time of Lent (the 40 days before the festival of Easter).Ehman, J. (2012, May 8). Religious diversity: Practical points for healthcare providers. Penn Medicine: Pastoral Care and Education. https://www.uphs.upenn.edu/pastoral/resed/diversity_points.html Hindu Patients - Hindu patients may express strong, culturally-based concerns about modesty, especially regarding treatment by someone of the opposite sex. Genital and urinary issues are often not discussed with a spouse present. - Hindus are often strictly vegetarian and do not consume meat or animal by-products. For such patients, even medications that are produced using animals are likely to be problematic. Some Hindus may also refrain from eating certain vegetables, like onions or garlic. - Fasting is a common practice in Hinduism, and patients may wish to discuss the implications in light of the medical/dietary care plan. - The act of washing is generally conceived as requiring running water, either from a tap or (poured) from a pitcher. A patient may have a strong desire to wash their hands after meals. See Figure 18.11“hindu-1588337_960_720.jpg” by gauravaroraji0 is licensed under CC0 for an image of a Hindu worshipping with water. - For many Hindu patients, there is a cultural norm to use the right hand for “clean” tasks like eating (often without utensils) and their left hand for “unclean” tasks like toileting. Medical and nursing staff should consider this right-left significance before hindering a patient’s hand or arm movement in any way. Discuss these preferences with the patient. - Patients may wear jewelry or adornments that have strong cultural and religious meaning, and staff should not remove these without discussing the matter with the patient or family. - Hinduism teaches that death is a crucial “transition” with karmic implications. There may be a strong desire that death occurs in the home rather than in the hospital. Family may wish to perform a number of pre-death rituals (for example, tying a thread around the person’s neck or wrist). After death, family members may request to wash the patient’s body (by family members of the same sex as the patient). - Family may request constant attendance of the deceased’s body. A family member or representative may wish to accompany the body to the morgue (where the person may sit outside any restricted area yet relatively near the body).Ehman, J. (2012, May 8). Religious diversity: Practical points for healthcare providers. Penn Medicine: Pastoral Care and Education. https://www.uphs.upenn.edu/pastoral/resed/diversity_points.html Jehovah’s Witness Patients - The most defining tenant for Jehovah’s Witnesses in health care is the strict prohibition against receiving blood (i.e., red blood cells, white blood cells, platelets, or plasma) by transfusion (even the transfusion of a patient’s stored blood), in medication using blood products, or in food. Some blood fractions (such as albumin, immunoglobulin, and hemophiliac preparations) are allowed, but patients are guided by their own conscience. - Organ donation and transplantation are allowed, but patients are guided by their own conscience. - Jehovah’s Witnesses are usually well-prepared to work with health care providers to seek all possible options for treatment that do not conflict with religious concerns. It is very common for adults to carry a card at all times stating religiously-based directives for treatment without blood. - Contrary to popular misconceptions, faith-healing is not a part of Jehovah’s Witness tradition. Prayers are often said for comfort and endurance. - Tradition of Jehovah’s Witnesses does not teach that those who die experience an immediate afterlife. It would be inappropriate to say to the family of a deceased patient, “He’s in a better place now.” - Jehovah’s Witnesses do not celebrate birthdays or Christian “holidays.”Ehman, J. (2012, May 8). Religious diversity: Practical points for healthcare providers. Penn Medicine: Pastoral Care and Education. https://www.uphs.upenn.edu/pastoral/resed/diversity_points.html Jewish Patients - Some Jewish patients may strictly observe a rule not to “work” on the Sabbath (from sundown on Friday until sundown on Saturday) or on religious holidays. If so, this religious injunction against “work,” including prohibitions against using certain tools or engaging in tasks that initiate use of electricity, can prevent tasks like writing, flipping a light switch, pushing buttons to call a nurse, adjusting a motorized bed, or operating a patient controlled analgesia (PCA) pump. The tearing of paper can be considered “work,” so roll toilet paper may need to be replaced with an opened box of individual sheets. Medical procedures should not be scheduled during the Sabbath or religious holidays (unless they are life-saving) nor should hospital discharges be planned during such times without the consent of the patient. While these restrictions on “work” are generally associated with Orthodox Judaism, they may be important for any Jewish patient. - Jewish holidays are usually highly significant for patients, especially Passover in the spring and Rosh Hashanah and Yom Kippur in the fall. These holidays may affect the scheduling of medical procedures and may involve dietary changes (related to a need for special food or to a desire to fast). All Jewish holidays run from sundown-to-sundown. - Jewish patients often request a special Kosher diet in accordance with religious laws that govern the preparation of certain foods (e.g., beef), the prohibition of certain foods (e.g., pork and gelatin), or the combination of some food (e.g., beef served with dairy products). During the holiday of Passover, an important distinction is made between food that is merely “Kosher” and that which is specifically “Kosher for Passover.” Hand washing before eating may have a religious significance. - Some Jewish patients may have culturally-based concerns about modesty, especially regarding treatment by someone of the opposite sex. However, because Jewish tradition holds the expertise of medical practitioners in high regard, this may reduce concerns about treatment by the opposite sex. - Questions about the withholding or withdrawing of life-sustaining therapy are deeply debated within Judaism, and some Jews are strongly opposed to the idea. Family members often wish to consult with a rabbi about the specific circumstances and decisions regarding end-of-life care. - After a patient has died, Jewish tradition directs that burial happen quickly and that there be no autopsy (unless the autopsy is deemed necessary by a mandate from the Medical Examiner). Also, the family may request that a family member or representative constantly accompany the body in the hospital or even to the morgue (where the person may sit outside any restricted area yet relatively near the body) to say prayers and read psalms. - There may be a request that amputated limbs be made available for burial. Details should be arranged through the patient’s/family’s funeral home. - Jewish religious laws pose a complex set of restrictions that can affect medical decisions, and patients or family members may request to speak with a rabbi to determine the moral propriety of any particular decision. Exceptions are often made when an action is understood in terms of “saving a life,” such as emergency surgery or organ donation during the Sabbath. The value of “saving a life” is held in extremely high regard in Jewish tradition. - It is common for male Jewish patients to wear a yarmulke or kippah (skull cap) during prayer, and some Jews may wish to keep them on at all times. Patients or family members may wear prayer shawls and use phylacteries (two small boxes containing scriptural verses and having leather straps, worn on the forehead and forearm during prayer). There may be a request that at least ten people (called a minyan) be allowed in the patient’s room for prayer. See Figure 18.12“Casamento_judeu1.jpg” by David Berkowitz is licensed under CC BY 2.0 for an image of a skull cap worn during prayer. - A Jewish person need not be religious to identify culturally as “Jewish” and may observe Jewish religious traditions for cultural reasons. - The word “Jew” is commonly used within Jewish culture, but non-Jews should be mindful of its complex historical connotations that can sometimes be perceived as disrespectful when spoken by non-Jews.Ehman, J. (2012, May 8). Religious diversity: Practical points for healthcare providers. Penn Medicine: Pastoral Care and Education. https://www.uphs.upenn.edu/pastoral/resed/diversity_points.html Muslim Patients - Muslim patients may express strong concerns about modesty, especially regarding treatment by someone of the opposite sex. A Muslim woman may need to cover her body completely and should always be given time and opportunity to do so before anyone enters her room. Women may also request that a family member be present during an exam and may desire to remain clothed during an exam if at all possible. Muslim men may find examination by a woman to be extremely challenging. Nudity is emphatically discouraged. There should be no casual physical contact by non-family members of the opposite sex (such as shaking hands). Some Muslims may avoid eye contact as a function of modesty. - Muslims may specifically request a diet in accordance with religious laws for “Halal” food, though many Muslims opt for a vegetarian diet as a simple way to avoid religious prohibitions against such things as pork products or gelatin. Forbidden foods are referred to as “Haraam.” - Muslim dietary regulation can affect patients’ use of medications, especially drugs that have pork origins or that contain gelatin or alcohol. The dietary prohibition against alcohol has occasionally raised questions about Muslims’ use of alcohol-based hand rubs in the hospital. Because hand rubs do not have an intoxicating effect and are used for life-saving hygiene, any concern should be addressed thoroughly and sensitively and perhaps with the input of an imam. An imam is a person who leads prayers in a mosque. - The act of washing may require running water, either from a tap or poured from a pitcher. As a result, Muslim patients typically do not feel truly cleaned by a sponge bath. Many Muslims wash with running water before and after meals and also before prayers. - Muslim prayers are conducted five times a day. Patients may desire to pray by kneeling and bending to the floor, but Islamic tradition recognizes circumstances when this is not medically advisable. If patients are disturbed by their inability to pray on the floor, advice should be encouraged from an imam. See Figure 18.13“Mosque.jpg” by Antonio Melina/Agência Brasil is licensed under CC BY 3.0 for an image of Muslim men prostrate in prayer. - Muslim patients may react to suffering with emotional reserve and may hesitate to express the need for pain management. Some may even refuse pain medication if they understand the experience of their pain to be spiritually enriching. - There may be a request that amputated limbs be made available for burial. Details should be arranged through the patient’s/family’s funeral home. - Muslim tradition generally discourages the withholding or withdrawing of life-sustaining therapy. However, because decisions on this subject involve the particular circumstances of the patient and the complexities of medical treatments, family members who are morally conflicted may wish to bring an experienced imam into their discussion with physicians. - A family member may request to be present with a dying person, so as to be able to whisper a proclamation of faith in the patient’s ear right before death. (Similarly, a husband may request to be present at a birth to whisper a proclamation of faith in the ear of the newborn.) - After a death, the family may request to wash the patient and to position their bed to face Mecca. The patient’s head should rest on a pillow. - Burial is usually accomplished as soon as possible. Muslim families rarely allow for autopsy unless there is an order by a Medical Examiner. Some Muslims may consider organ donation, but the subject is open to great differences of opinion within Islamic circles. - During the thirty-day month of Ramadan, Muslims refrain from food and drink from dawn until sundown. Physicians should explore with patients whether it is medically appropriate to fast while in the hospital. If so, investigate options for predawn meals, for providing patients with dates and spring water in the late afternoon (a traditional way to break the daily fast), and for delaying dinner until after sunset. While anyone who is ill is not obligated to fast, the Ramadan observance can be powerfully meaningful to patients if they can participate. The month of Ramadan shifts according to a lunar calendar, and when it occurs during the summertime, longer days can make the fast more physically stressful.Ehman, J. (2012, May 8). Religious diversity: Practical points for healthcare providers. Penn Medicine: Pastoral Care and Education. https://www.uphs.upenn.edu/pastoral/resed/diversity_points.html Pentecostal Patients - Pentecostal patients may pray exuberantly. Noise concerns in a hospital can sometimes present a problem in this regard, but simply shutting the door to the patient’s room can usually provide an adequate solution. - Pentecostals may pray by “speaking in tongues,” expression of words that seem unintelligible to an individual hearer but holds very deep religious significance for worshippers. - Patients or families may request that relatively large numbers of people be allowed in the patient’s room for prayer. - Patients or families may express strong belief in miraculous healing.Ehman, J. (2012, May 8). Religious diversity: Practical points for healthcare providers. Penn Medicine: Pastoral Care and Education. https://www.uphs.upenn.edu/pastoral/resed/diversity_points.html 18.4 Applying the Nursing Process Open Resources for Nursing (Open RN) Now that we have reviewed the concepts related to spirituality and discussed beliefs and practices of common world religions, let’s apply the nursing process to promoting spiritual health. Assessment Subjective Assessment Agencies often provide a standardized spiritual assessment tool to complete when a patient is admitted. If a standardized assessment tool is not available, the FICA model can be used.Dameron, C. M. (2005). Spiritual assessment made easy… With acronyms! Journal of Christian Nursing, 22(1). https://www.nursingcenter.com/journalarticle?Article_ID=725343&Journal_ID=642167&Issue_ID=725337 The FICA model contains open-ended questions to ask patients about their personal spiritual beliefs in a way that is open and nonjudgmental. - F–Faith or beliefs: What are your spiritual beliefs? Do you consider yourself spiritual? What things do you believe in that give meaning to life? - I–Importance and influence: Is faith/spirituality important to you? How has your illness and/or hospitalization affected your personal practices /beliefs? - C–Community: Are you connected with a faith center in the community? Does it provide support/comfort for you during times of stress? Is there a person/group/leader who supports/assists you in your spirituality? - A–Address: What support can we provide to support your spiritual beliefs/practices?Dameron, C. M. (2005). Spiritual assessment made easy… With acronyms! Journal of Christian Nursing, 22(1). https://www.nursingcenter.com/journalarticle?Article_ID=725343&Journal_ID=642167&Issue_ID=725337 The HOPE tool is also helpful for incorporating spiritual assessment questions into a medical interview. HOPE stands for: H: Sources of hope, meaning, comfort, strength, peace, love and connection O: Organized religion P: Personal spirituality and practices E: Effects of spirituality on medical care and end-of-life issues The first part of the mnemonic, H, pertains to a patient’s basic spiritual resources, such as sources of hope, without immediately focusing on religion or spirituality. This approach allows for meaningful conversation with a variety of patients, including those whose spirituality lies outside the boundaries of traditional religion or those who have been alienated in some way from their religion. It also allows those for whom religion, God, or prayer is important to volunteer this information. The second and third letters, O and P, refer to areas of inquiry about the importance of organized religion in patients’ lives and the specific aspects of their personal spirituality and practices that are most helpful. A useful way to introduce these questions is a normalizing statement such as: “For some people, their religious or spiritual beliefs act as a source of comfort and strength in dealing with life’s ups and downs. Is this true for you?”Anandarajah, G., and Hight, E. (2001). Spirituality and medical practice: Using the HOPE questions as a practical tool for spiritual assessment. American Family Physician. 63(1), 81-9. https://www.aafp.org/afp/2001/0101/p81.html Objective Assessment In addition to asking open-ended questions, it is important for the nurse to observe patients for cues indicating difficulties in finding meaning, purpose, or hope in life. It is also important to monitor for supportive relationships.Ackley, B., Ladwig, G., Makic, M. B., Martinez-Kratz, M., & Zanotti, M. (2020). Nursing diagnosis handbook: An evidence-based guide to planning care (12th ed.). Elsevier, pp. 869-872. Patients experiencing chronic or serious illness may make statements indicating spiritual distress that should cue the nurse that spiritual care is needed. Examples of these statements/concepts are as follows: - Lack of Meaning: “I am not the person I used to be.” - Hope: “I have nothing left to hope for.” - Mystery: “Why me?” - Isolation: “All my family and friends are gone.” - Helplessness: “I have no control over my life anymore.”Puchalski, C. M., Vitillo, R., Hull, S. K., & Reller, N. (2014). Improving the spiritual dimension of whole person care: Reaching national and international consensus. Journal of Palliative Medicine, 17(6), 642–656. https://doi.org/10.1089/jpm.2014.9427 Diagnoses See Table 18.4 for common NANDA-I diagnoses associated with spiritual health.Herdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York, pp. 365, 372-377. Table 18.4 Common NANDA-I Nursing Diagnoses Related to Spiritual HealthHerdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York, pp. 365, 372-377. \| NANDA-I Diagnosis \| Definition \| Defining Characteristics \| \|---\|---\|---\| \| Readiness for Enhanced Spiritual Well-Being \| A pattern of experiencing and integrating meaning and purpose in life through connectedness with self, others, art, music, literature, nature, and/or a power greater than oneself, which can be strengthened \| Connections to Self Connections with Others Connections with Art, Music, Literature, and Nature Connections with Power Greater than Self \| \| Impaired Religiosity \| Impaired ability to exercise reliance on beliefs and/or participate in rituals of a particular faith tradition \| \| \| Spiritual Distress \| A state of suffering related to the impaired ability to experience meaning in life through connections with self, others, the world, or a superior being \| \| Sample Nursing Diagnosis Statements Readiness for Enhanced Spiritual Well-Being Many people experienced feelings of isolation as they sheltered at home during the COVID-19 pandemic. A sample PES statement for this shared experience is, Readiness for Enhanced Spiritual Well-Being as evidenced by expressed desire to enhance time outdoors. The nurse could encourage patients to visit local parks and walk outdoors while wearing a mask and maintaining social distancing. Recall that when a PES statement is created for a health promotion diagnosis, the defining characteristics are provided as evidence of the desire of the patient to improve their current health status.Herdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York, pp. 365, 372-377. Impaired Religiosity Hospitalized patients may be unable to attend religious services they are accustomed to attending. A sample PES statement is, “Impaired Religiosity related to environmental barriers to practicing religion as evidenced by difficulty adhering to prescribed religious beliefs.” The nurse could contact the patient’s pastor to arrange a visit or determine if services can be viewed online. Spiritual Distress Events that place patient populations at risk for developing spiritual distress include birth of a child, death of a significant other, exposure to death, a significant life transition, severe illness or injury, exposure to natural disaster, racial conflict, or an unexpected life event.Herdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York, pp. 365, 372-377. Associated conditions that place a person at risk for developing spiritual distress include actively dying, chronic illness, illness, loss of a body part, loss of function of a body part, or a treatment regimen.Herdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York, pp. 365, 372-377. For example, a patient diagnosed with life-threatening medical diagnoses like cancer may experience spiritual distress as they move through the typical stages of loss. A sample PES statement is, “Spiritual Distress related to anxiety associated with illness as evidenced by crying, insomnia, and questioning the meaning of suffering.” A nurse would implement interventions to enhance coping. Outcome Identification Goals and SMART outcomes should be customized to each patient and their situation. When a patient has the nursing diagnosis Readiness for Enhanced Spiritual Well-Being, a sample goal statement is, “The patient will demonstrate hope as evidenced by the following indicators: expressed expectation of a positive future, faith, optimism, belief in self, sense of meaning in life, belief in others, and inner peace.”Ackley, B., Ladwig, G., Makic, M. B., Martinez-Kratz, M., & Zanotti, M. (2020). Nursing diagnosis handbook: An evidence-based guide to planning care (12th ed.). Elsevier, pp. 869-872. An example of a related SMART outcome is, “The patient will express a sense of meaning and purpose in life by discharge.”Ackley, B., Ladwig, G., Makic, M. B., Martinez-Kratz, M., & Zanotti, M. (2020). Nursing diagnosis handbook: An evidence-based guide to planning care (12th ed.). Elsevier, pp. 869-872. When a patient has the nursing diagnosis Spiritual Distress, a sample goal statement is, “The patient will demonstrate improved spiritual health as evidenced by one of the following indicators: feelings of faith, hope, meaning, and purpose in life with connectedness with self and others to share thoughts, feelings, and beliefs.”Ackley, B., Ladwig, G., Makic, M. B., Martinez-Kratz, M., & Zanotti, M. (2020). Nursing diagnosis handbook: An evidence-based guide to planning care (12th ed.). Elsevier, pp. 869-872. A sample SMART outcome is, “The patient will express a purpose in life by discharge.”Ackley, B., Ladwig, G., Makic, M. B., Martinez-Kratz, M., & Zanotti, M. (2020). Nursing diagnosis handbook: An evidence-based guide to planning care (12th ed.). Elsevier, pp. 869-872. Planning Interventions Providing Spiritual Care When providing spiritual care, the RN must not impose their religious or spiritual beliefs on the patient. There are several guidelines for therapeutically implementing nursing interventions to support patients’ spiritually: - Take cues from the patient: When bringing up spiritual health with patients, understand this may be a difficult topic for them to discuss. Let them lead the conversation and do not press further than they want to share. Also, be aware of the patient’s nonverbal cues. They may be saying one thing but their body language is saying something different. Gently point out the contradiction and seek clarification. For example, a patient may state that they don’t blame God for their illness, but begin to tear up as they say it. By responding, “I noticed you became tearful when you said that…what is causing the tears,” the door is opened for them to share more of their thoughts and feelings. - Ask the patient how you can support them spiritually: An important way to assist a patient with their spiritual health is to ask them what they need to feel supported in their faith and then try to accommodate their requests, if possible. For example, perhaps they would like to speak to their clergy, spend some quiet time in meditation or prayer without interruption, or go to the onsite chapel. Explain that spiritual health helps the healing process. Many agencies have chaplains onsite that can be offered to patients as a spiritual resource. - Support patients within their own faith tradition: Because patients can sometimes feel as if they are a captive audience, it is not appropriate for the nurse to take this opportunity to attempt to persuade a patient towards a preferred religion or belief system. The role of the nurse is to respect and support the patient’s values and beliefs, not promote the nurse’s values and beliefs. - Listen to a patient’s fears and concerns without adding your own stories: In an effort to empathize with a patient who is telling their story, it is easy for the nurse to start adding personal examples from their own life. Although this may seem helpful, it is usually only distracting and shifts the focus from the patient to the nurse. Focus on the patient’s fears and concerns. Name and validate the emotions that are heard when possible. Sometimes patients don’t realize what they are feeling until it is pointed out to them. - Pray with a patient if requested (or provide someone who will): Some nurses may feel reluctant to pray with patients when they are asked for various reasons. They may feel underprepared, uncomfortable, or unsure if they are “allowed to.” Nurses are encouraged to pray with their patients to support their spiritual health, as long as the focus is on the patient’s preferences and beliefs, not the nurse’s. See Figure 18.14“Praying_with_Patient.jpg” by Ahs856 is licensed under CC BY-SA 4.0 for an image of a nurse praying with a patient. Having a short, simple prayer ready, that is appropriate for any faith, may help in this situation. If a nurse does not feel comfortable praying, the chaplain should be requested to participate in prayer with the patient. - Share an encouraging thought or word: Similar to the preceding prayer suggestion, a scripture verse (based on the patient preferences) or an inspirational poem may be helpful to share during difficult times. Having a few verses or thoughts readily available can be very helpful during critical moments.Nourian, F. (2018, March 16). 9 ways to provide spiritual care to your patients & their families. AdventHealth. https://careers.adventhealth.com/blog/9-ways-to-provide-spiritual-care-to-patients-and-their-families - Use presence and touch: Sometimes the mere presence of a nurse is spiritually comforting for patients. Words are not always needed. It can be very comforting to know that someone will be sitting quietly next to them as they fall asleep or are in pain. Touch can also be a very powerful therapeutic tool to provide comfort (after asking permission of the patient).Nourian, F. (2018, March 16). 9 ways to provide spiritual care to your patients & their families. AdventHealth. https://careers.adventhealth.com/blog/9-ways-to-provide-spiritual-care-to-patients-and-their-families See the following box for a summary of therapeutic interventions that nurses can implement to provide spiritual support. Review additional interventions for enhancing coping for patients and family members experiencing grief in the “Grief and Loss” chapter. Therapeutic Nursing Interventions to Provide Spiritual SupportJohnson, M., Moorhead, S., Bulechek, G., Butcher, H., Maas, M., & Swanson, E. (2012). NOC and NIC linkages to NANDA-I and clinical conditions: Supporting critical reasoning and quality care. Elsevier, pp. 222-223.,Butcher, H., Bulechek, G., Dochterman, J., & Wagner, C. (2018). Nursing Interventions Classification (NIC). Elsevier, pp. 351-353.,Ackley, B., Ladwig, G., Makic, M. B., Martinez-Kratz, M., & Zanotti, M. (2020). Nursing diagnosis handbook: An evidence-based guide to planning care (12th ed.). Elsevier, pp. 869-872. - Use therapeutic communication to establish trust and empathetic caring. - Be present and actively listen to the individual’s feelings and express empathy. - Be open to the individual’s expressions of loneliness and powerlessness. - Be open to the individual’s feelings about illness and/or death. - Encourage the individual to reminisce and review their past and focus on events and relationships that provided spiritual strength and support. - Provide privacy and quiet time for spiritual activities. - Offer opportunities for the patient to practice their religion. - Encourage the patient to engage in spiritual, meditative, or mind-body practices to promote spiritual healing. - Arrange visits with the chaplain, patient’s pastor, or other spiritual advisor. - Pray with the individual, as appropriate. - Provide spiritual music, literature, radio, television, or online programs as appropriate. - Promote hope however the individual defines it for their situation without providing false reassurance. - Encourage forgiveness. - Encourage participation in interactions with family members, friends, and others. - Encourage participation in support groups Implementing Interventions Nurses should support patients’ spiritual and religious preferences when implementing interventions to support their spiritual well-being. The nurse should respect and listen to the patient’s expression of beliefs and not impose their own beliefs on the patient. Spiritual or religious practices should be accommodated if safe and feasible to do so. If a patient has a spiritual belief, value, or practice that conflicts with their treatment plan, the nurse should explain the rationale for the intervention or treatment. If the patient is not willing to complete the treatment as planned due to their spiritual or religious beliefs, the nurse should attempt to negotiate the treatment plan with the patient and/or health care provider. For example, a nurse can advocate for rescheduling a procedure after the Sabbath or modifying the dietary plan and medication administration times during Ramadan. Evaluation When evaluating the effectiveness of interventions in promoting a patient’s spiritual health, refer to the overall goal, “The patient will demonstrate spiritual health as evidenced by the following indicators: feelings of faith, hope, meaning, and purpose in life with connectedness with self and others.”Ackley, B., Ladwig, G., Makic, M. B., Martinez-Kratz, M., & Zanotti, M. (2020). Nursing diagnosis handbook: An evidence-based guide to planning care (12th ed.). Elsevier, pp. 869-872. From there, review the patient’s progress toward the personalized SMART outcomes that have been customized to their situation. 18.5 Spiritual Care of Self Open Resources for Nursing (Open RN) Provision 5 of the American Nurses Association Code of Ethics states, “The nurse owes the same duties to self as to others, including the responsibility to promote health and safety, preserve wholeness of character and integrity, maintain competence, and continue personal and professional growth.”American Nurses Association. (2015). Code of ethics for nurses with interpretive statements. American Nurses Association. https://www.nursingworld.org/practice-policy/nursing-excellence/ethics/code-of-ethics-for-nurses/coe-view-only/ Spiritual care is associated with better health and well-being for everyone, including nurses and nursing students. A desire to help others in need is an important part of spirituality, which has been described as a life-giving force based on faith, discovering meaning and purpose in life, and offering the gift of self to others.Rudolfsson, G., Berggren, I., & da Silva, A. B. (2014). Experiences of spirituality and spiritual values in the context of nursing – An integrative review. The Open Nursing Journal, 8, 64–70. https://doi.org/10.2174/1874434601408010064 Spiritual resources can help nurses and nursing students overcome the emotional toil associated with caring for seriously ill and dying patients and prevent compassion fatigue and burnout. Read more about compassion fatigue and burnout in the “Grief and Loss” chapter. Many spiritual traditions use contemplative practices to increase compassion, empathy, and quiet the mind.Delagran, L. (n.d.). What is spirituality? University of Minnesota. https://www.takingcharge.csh.umn.edu/what-spirituality Examples of contemplative practices and other methods to build spiritual strength include the following: - Meditation can induce feelings of calm and clear-headedness and improve concentration and attention. Research has shown that meditation increases the brain’s gray matter density, which can reduce sensitivity to pain, enhance the immune system, help regulate difficult emotions, and relieve stress. Mindfulness meditation in particular has been proven helpful for people with depression and anxiety, cancer, fibromyalgia, chronic pain, rheumatoid arthritis, type 2 diabetes, chronic fatigue syndrome, and cardiovascular disease.Delagran, L. (n.d.). What is spirituality? University of Minnesota. https://www.takingcharge.csh.umn.edu/what-spirituality - Yoga is a centuries-old spiritual practice that creates a sense of union within the practitioner through physical postures, ethical behaviors, and breath expansion. The systematic practice of yoga has been found to reduce inflammation and stress, decrease depression and anxiety, lower blood pressure, and increase feelings of well-being.Delagran, L. (n.d.). What is spirituality? University of Minnesota. https://www.takingcharge.csh.umn.edu/what-spirituality - Journaling can help a person become more aware of their inner life and feel more connected to experiences. Studies show that writing during difficult times may help a person find meaning in life’s challenges and become more resilient in the face of obstacles. When journaling, it can be helpful to focus on three basic questions: What experiences give me energy? What experiences drain my energy? Were there any experiences today where I felt alive and experienced “flow”? Allow yourself to write freely, without stopping to edit or worry about spelling and grammar.Delagran, L. (n.d.). What is spirituality? University of Minnesota. https://www.takingcharge.csh.umn.edu/what-spirituality - Prayer can elicit the relaxation response, along with feelings of hope, gratitude, and compassion, all of which have a positive effect on overall well-being. There are several types of prayer rooted in the belief that there is a higher power that has some level of influence over one’s life. This belief can provide a sense of comfort and support in difficult times. A recent study found that clinically depressed adults who believed their prayers were heard by a concerned presence responded much better to treatment than those who did not believe.Delagran, L. (n.d.). What is spirituality? University of Minnesota. https://www.takingcharge.csh.umn.edu/what-spirituality - Find a spiritual community and friends. Join a spiritual group, such as a church, synagogue, temple, mosque, meditation center, yoga class, or other local group that meets to discuss spiritual issues. The benefits of social support are well-documented, and having a spiritual community to turn to for fellowship can provide a sense of belonging and support.Delagran, L. (n.d.). What is spirituality? University of Minnesota. https://www.takingcharge.csh.umn.edu/what-spirituality - Nurture your relationships with family, significant others, and friends. Relationships aren’t static – they are living, dynamic aspects of our lives that require attention and care. To benefit from strong connections with others, you should take charge of your relationships and put in the time and energy you would any other aspect of your well-being. It can be helpful to create rituals together. With busy schedules and the presence of online social media that offer the façade of real contact, it’s very easy to drift from friends. Research has found that people who deliberately make time for gatherings or trips enjoy stronger relationships and more positive energy. An easy way to do this is to create a standing ritual that you can share and that doesn’t create more stress, such as talking on the telephone on Fridays or sharing a walk during lunch breaks.Delagran, L. (n.d.). What is spirituality? University of Minnesota. https://www.takingcharge.csh.umn.edu/what-spirituality - Mindfulness has been defined as, “Awareness that arises through paying attention, on purpose, in the present moment, and nonjudgmentally.” Mindfulness has also been described as, “Non-elaborative, nonjudgmental, present-centered awareness in which each thought, feeling, sensation that arises is acknowledged and accepted as it is.” Mindfulness helps us be present in our lives and gives us some control over our reactions and repetitive thought patterns. It helps us pause, get a clearer picture of a situation, and respond more skillfully. Compare your default state to mindfulness when studying for an exam in a difficult course or preparing for a clinical experience. What do you do? Do you tell yourself, “I am not good at this” or “I am going to look stupid”? Does this distract you from paying attention to studying or preparing? How might it be different if you had an open attitude with no concern or judgment about your performance? What if you directly experienced the process as it unfolded, including the challenges, anxieties, insights, and accomplishments, while acknowledging each thought or feeling and accepting it without needing to figure it out or explore it further? If practiced regularly, mindfulness helps a person start to see the habitual patterns that lead to automatic negative reactions that create stress. By observing these thoughts and emotions instead of reacting to them, a person can develop a broader perspective and can choose a more effective response.Delagran, L. (n.d.). What is spirituality? University of Minnesota. https://www.takingcharge.csh.umn.edu/what-spirituality - Spending time in nature is cited by many individuals as a spiritual practice that contributes to their mental health.Yamada, A., Lukoff, D., Lim, C., & Mancuso, L. (2020). Integrating spirituality and mental health: Perspectives of adults receiving public mental health services in California. Psychology of Religion and Spirituality, 12(3), 276–287. https://doi.org/10.1037/rel0000260 Explore additional resources about developing spiritual well-being to avoid burnout at the University of Minnesota’s Earl E. Bakken Center for Spirituality & Healing. 18.6 Putting It All Together Patient Scenario Mr. Yun is a 34-year-old man presenting to his physician’s office with complaints of difficulty concentrating, sadness, and anxiety. The patient recently experienced the loss of his wife in a motor vehicle accident and reports difficulty sleeping and weight loss of greater than 15 pounds in the previous month. He reports feeling “hopeless” and “angry at God” for the loss that he has experienced. He states he used to attend religious services with his wife, but “That was really more of ‘her’ thing. I really don’t know what to believe anymore.” Applying the Nursing Process Assessment: The nurse notes that the patient is experiencing difficulty concentrating, feelings of sadness and hopelessness, and reported anxiety. He self-reports feeling hopeless, feelings of anger toward God, and uncertainty in his belief system. Based on the assessment information that has been gathered, the following nursing care plan is created for Mr. Yun: Nursing Diagnosis: Spiritual Distress related to loss of challenged belief system as manifested by self-reported “hopelessness,” being “angry at God,” and general uncertainty in beliefs. Overall Goal: The patient will demonstrate improved spirituality. SMART Expected Outcome: By the end of the teaching session, Mr. Yun will describe a spiritual practice that provides him comfort. Planning and Implementing Nursing Interventions: The nurse will identify the factors that influence the patient’s personal belief system. The nurse will provide support to the patient and allow the patient to express emotions and anger. The nurse will observe and listen empathetically in the communication experience. The nurse will encourage the use of spiritual resources and ask the patient permission to contact a chaplain. Sample Documentation Mr. Yun exhibits signs of spiritual distress in relation to the loss of his personal belief system as the result of his wife’s recent death. He verbalizes anger, hopelessness, and uncertainty in his belief system. However, he does find comfort in spending time outdoors in nature. A chaplain has been contacted with the patient’s permission to address Mr. Yun’s spiritual needs. Evaluation At the end of the teaching session, the nurse explains that with his permission, a chaplain will call Mr. Yun at home to follow up. Mr. Yun grants permission for the referral. The nurse asks what other spiritual resources Mr. Yun plans to use at home. Mr. Yun explains that he will purposefully go for daily walks outdoors to spend time in nature. The SMART outcome was “met.” 18.7 Learning Activities Open Resources for Nursing (Open RN) Learning Activities (Answers to “Learning Activities” can be found in the “Answer Key” at the end of the book. Answers to interactive activity elements will be provided within the element as immediate feedback.) An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=1989#h5p-74 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=1989#h5p-43 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=1989#h5p-44 XVIII Glossary Open Resources for Nursing (Open RN) Chaplains: Trained professionals in hospitals, nursing homes, assisted living facilities, and hospices that assist with the spiritual, religious, and emotional needs of patients, families, and staff. Chaplains support and encourage people of all religious faiths and cultures and customize their approach to each individual’s background, age, and medical condition. Holism: The concept that a human is composed of a mind, body, and soul integrated into an inseparable whole. Religion: A unified system of beliefs, values, and practices that a person holds sacred or considers to be spiritually significant. Some people associate religion with a place of worship (e.g., a synagogue or church), a practice (e.g., attending religious services, receiving communion, or going to confession), or a concept that guides one’s daily life (e.g., sin or kharma). Spiritual distress: A state of suffering related to the impaired ability to experience meaning in life through connections with self, others, the world, or a superior being. Spirituality: A dynamic and intrinsic aspect of humanity through which persons seek ultimate meaning, purpose, and transcendence and experience relationships to self, family, others, community, society, nature, and the significant or sacred. Spirituality is expressed through beliefs, values, traditions, and practice. Spiritual well-being: A pattern of experiencing and integrating meaning and purpose in life through connectedness with self, others, art, music, literature, nature, and/or a power greater than oneself. Transcendence: An understanding of being part of a greater picture or of something greater than oneself, such as the awe one can experience when walking in nature. It can also be expressed as a search for the sacred through subjective feelings, thoughts, and behaviors. Care of the Older Adult XIX 19.1 Care of the Older Adult Introduction Learning Objectives - Consider all aspects of diversity, including age - Differentiate between normal and abnormal findings for older adults - Detail specific adaptations in patient care to accommodate the needs of older adults The needs of the older adult population will continue to influence health care through this century. The aging “baby boomer” population, along with an increased average life span of Americans, has led to an increased number of older adults and is only expected to grow. The U.S. Census Bureau projects that 1 in 5 Americans will be over the age of 65 by 2030, and by 2034, the number of older individuals will outnumber children for the first time in U.S. history.United States Census Bureau. (2018, March 13). Older people projected to outnumber children for the first time in U.S. history. https://www.census.gov/newsroom/press-releases/2018/cb18-41-population-projections.html Each individual ages in their own way, and the physical, psychosocial, and cognitive health of older individuals varies widely. Because of this broad scope of health and illness in the aging population, providing nursing care that meets the needs of each older adult can be challenging. Additionally, although there are common physiological changes that occur with aging, many individuals ignore symptoms by erroneously attributing them to the aging process. For example, many older adults mistakenly believe that pain from arthritis is a normal part of growing older and do not seek treatment, resulting in decreased physical activity that puts them at increased risk for developing chronic disease. Providing individualized nursing care and patient education to older adults can promote effective preventative health care and self-management that maintains and enhances their quality of life.Sarkisian, C. A., Hays, R. D., Berry, S., & Mangione, C. M. (2002). Development, reliability, and validity of the expectations regarding aging (ERA-38) survey. The Gerontologist, 42(4), 534-542. https://doi.org/10.1093/geront/42.4.534 Let’s begin by reviewing basic concepts related to the aging process. 19.2 Basic Concepts Ageism Gerontology is the study of the social, cultural, psychological, cognitive, and biological aspects of aging. There are many stereotypes and negative attitudes about aging adults that persist in the US and around the world. This bias can be linked to a general lack of knowledge about the aging process and misunderstandings about older adults. Because of these influences, many individuals have anxiety about aging that can lead to negative stereotypes of older individuals called ageism.Merz, C. C., Stark, S. L., Morrow-Howell, N. L., & Carpenter, B. D. (2016). When I’m 64: Effects of an interdisciplinary gerontology course on first-year undergraduates’ perceptions of aging. Gerontology & Geriatrics Education, 39(1), 35-45. https://doi.org/10.1080/02701960.2016.1144600 Ageism among nurses and other health care professionals puts older people at risk. Research has demonstrated that ageism in health care negatively impacts older adults’ overall health, well-being, and quality of care received. Ageism results in increased risks of mortality, poor functional health, and slower recovery times from illness. Negative perceptions about aging can also lead to poor mental health and depression.Burnes, D., Sheppard, C., Henderson, C. R., Wassel, M., Cope, R., Barber, C., & Pillemer, K. (2019). Interventions to reduce ageism against older adults: A systematic review and meta-analysis. American Journal of Public Health, 109(8), e1-e9. https://doi.org/10.2105/AJPH.2019.305123 As you read this chapter, think about your own attitudes about aging and how these beliefs may impact the care you provide. Integrity Versus Despair Aging individuals must continually adjust to changes in health and physical strength, lifestyle changes as a result of retirement, the loss of significant others, and changing roles and relationships with family members and friends. As a result, older individuals may find it difficult to accept the changes associated with aging. Nurses can support older adults in maintaining a positive self-image and outlook by considering Erikson’s theory of development. Erikson’s theory of development describes the stage of older adulthood as “Integrity versus Despair.” This stage begins at approximately age 65 and ends at death. During this stage, older adults reflect on their accomplishments and the person they have become. If they feel they have led a successful life, they often feel satisfied and develop a sense of integrity. Conversely, individuals who feel unsuccessful or do not feel they achieved their life goals often feel unsatisfied and may experience hopelessness and despair that can lead to depression. Nurses can assist older adults in developing a sense of integrity by encouraging the patient to reminiscence about previous positive life events and relationships and cultivate a positive mindset of guiding the next generation.This work is a derivative of StatPearls by Orenstein and Lewis and is licensed under CC BY 4.0 Many older adults, especially those with declining health due to chronic disease, acknowledge that changes in their health status and mobility threaten the autonomy and independence they previously experienced throughout adulthood. As a result, many older adults strive to be autonomous so they are not overly reliant on others for their daily care. They often engage in self-management activities in response to changes in their health and physical strength, ranging from simple daily tasks, such as medication management, to more complex tasks, such as relocating to new residences that are better suited to their changes in physical and mental health. Research has found that when older adults are faced with declines in their physical health and/or cognitive abilities, they often draw upon experiences and skills acquired in earlier adulthood for the purpose of self-managing their new conditions. They reflect on their resilience used to overcome significant challenges faced in earlier adulthood and then apply skills and knowledge gained through previously productive activities to managing their new health changes. However, not all older adults have sufficient personal and external resources to devote towards successful self-management of their health conditions. Nurses can assist older adults by personalizing health self-management strategies that emphasize their existing skill sets and knowledge.Perry, T. E., Ruggiano, N., Shtompel, N., & Hassevoort, L. (2014). Applying Erikson’s wisdom to self-management practices of older adults: Findings from two field studies. Research on Aging, 37(3), 253-274. https://doi.org/10.1177/0164027514527974 Other Considerations Retirement In addition to the physiological changes that occur with aging, older adults vary in their level of activity. For example, many older adults continue working into their seventies and beyond. Individuals may choose to continue to work because of their sense of purpose or because of a need for income. Some older individuals experience a loss of identity when they retire because their work role was an important aspect of their life. Retirement can bring a sense of freedom and adventure, as well as a need to find new identity and purpose. Social Isolation Retirement and the loss of daily interaction with coworkers, as well as death of family members and friends, can lead to social isolation in the aging population. Social support impacts a person’s health and quality of life and should be included as part of the assessment. It is helpful for nurses to be familiar with community resources that provide socialization opportunities and provide referrals for patients in need of additional services. Modified Living Environment Although many aging adults live in assisted living facilities or skilled nursing centers, many older adults prefer to live at home. Modifications may be needed to the home environment to promote safety and independence. For example, grab bars, elevated toilet seats, and other modifications may be needed in the bathroom, along with good lighting, minimization of clutter, and removal of rugs throughout the home. Assessment of the home environment for safety and ease of mobility is an important aspect of home care nursing. If an older adult requires more care than family members are able to provide at home, nurses provide valuable information about available care options and make referrals to social workers and case managers. There are a wide variety community-based resources to enhance care for older adults. Local aging and disability resource centers (ADRCs) can help facilitate referrals based on specific needs of the older adult. Examples of other resources include adult day centers, home health agencies that provide personal care and nursing assistance, community-based residential facilities (CBRFs), and residential care apartment complexes (RCACs). If an older adult requires 24-hour nursing care, placement in a nursing home (also referred to as a skilled nursing facility) may be required. Use the following hyperlink to read more information about nursing home resources provided by the Centers for Medicare and Medicaid (CMS). Learn more about nursing home resources by reviewing the Nursing Home Resource Center provided by the Centers for Medicare and Medicaid (CMS). 19.3 Applying the Nursing Process Applying the Nursing Process: Assessment When performing a comprehensive assessment on an older adult, the findings are used to establish their baseline status of physical, cognitive, psychosocial, and spiritual well-being. It is appropriate to consider the potential impact of declining strength and physical functioning on their psychological status using Erikson’s developmental stage of “Integrity versus Despair.” It is also important to consider the impact of chronic disease on their ability to function and complete Activities of Daily Living (ADLs). Many older adults who are able to perform ADLs without assistance consider themselves healthy. When performing an assessment on an older adult, modification of communication techniques may be required, as discussed in the “Sensory Impairments” and “Cognitive Impairments” chapters. It is important to allow adequate time for older individuals to reply to questions thoughtfully and to move through the requests contained in a physical assessment comfortably. It is helpful to use an evidence-based tool to assess for frequent needs of older adults, such as the Fulmer SPICES tool. The SPICES tool focuses on areas of common problems for aging individuals and can lead to early intervention and treatment. The SPICES tool includes assessment of the following: S: Sleep Disorders P: Problems with Eating or Feeding I: Incontinence C: Confusion E: Evidence of Falls S: Skin BreakdownFulmer, T. (2019). Fulmer SPICES: An overall assessment tool for older adults. The Hartford Institute for Geriatric Nursing, New York University, Rory Meyers College of Nursing. https://hign.org/sites/default/files/2020-06/Try%20This%20General%20Assessment%201.pdf Several free assessment tools for common issues in older adults are located at The Hartford Institute of Geriatric Nursing website. Use the hyperlink in the following box to explore available tools. Unexpected Findings While cognitive impairment and memory deficits are not considered normal aspects of aging, there are common expected physiological changes that occur with aging. Nurses should be familiar with these expected findings so that deviations from the expected can be adequately addressed. See Table 19.3 for a comparison of expected versus unexpected findings in an older adult that require notification of the health care provider.Boss, G. R., & Seegmiller, J. E. (1981). Age-related physiological changes and their clinical significance. The Western Journal of Medicine, 135(6), 434–440. Table 19.3 Expected Versus Unexpected FindingsBoss, G. R., & Seegmiller, J. E. (1981). Age-related physiological changes and their clinical significance. The Western Journal of Medicine, 135(6), 434–440. \| Assessment \| Expected Findings \| New Unexpected Findings to Report to the Health Care Provider \| \|---\|---\|---\| \| Cardiovascular system \| \| CRITICAL CONDITIONS requiring immediate notification or contact of emergency services: Chest pain; new onset or changes in oxygenation \| \| Respiratory system \| \| CRITICAL CONDITIONS requiring immediate notification or contact of emergency services: Hemoptysis; decreased oxygen saturation levels not responding to treatments \| \| Musculoskeletal system \| \| CRITICAL CONDITIONS requiring immediate notification or contact of emergency services: Sudden onset of unilateral weakness, facial drooping, or slurred speech \| \| Genitourinary system \| \| CRITICAL CONDITIONS requiring immediate notification or contact of emergency services: Urine output less than 30 mL/hour \| \| Gastrointestinal system \| \| \| \| Integumentary system \| \| \| \| Endocrine system \| \| \| \| Immune system \| \| \| \| Reproductive system \| \| \| Health Promotion One of the goals of Healthy People 2030 is to improve the health and well-being for older adults. It is estimated that by 2060 almost a quarter of the U.S. population will be age 65 or older. Older adults are at higher risk for chronic health problems like diabetes, osteoporosis, and Alzheimer’s disease. In addition, 1 in 3 older adults fall each year, with falls being a leading cause of injury for this age group. Older adults are also more likely to go to the hospital for infectious diseases such as pneumonia that is a leading cause of death for this age group. Nurses can ensure older adults get preventive care, including vaccines to protect against the flu and pneumonia, to help them stay healthy. Other goals for older adults established by Healthy People 2030 include early detection of dementia with appropriate intervention; decreased hospitalization for urinary infections, falls, and pneumonia; decreased incidence of medication-related safety issues; improved physical activity; improved oral health; decreased complications of osteoporosis; and reduced vision loss from macular degeneration.Healthy People 2030. (n.d.). Older adults. https://health.gov/healthypeople/objectives-and-data/browse-objectives/older-adults Nurses can advocate for improved health care for older adults while actively involving them in decisions about their care and promoting their quality of life. Common areas of health promotion for older adults include nutrition, physical activity, safe medication use, and psychosocial well-being. Nutrition Heart disease, cancer, chronic lung disease, and stroke are the leading causes of death in older adults. Nurses can provide patient education that focuses on good nutrition, physical activity, smoking cessation, and moderate alcohol use to promote improved health outcomes.Centers for Disease Control and Preventive Medicine. (2021, March 1). Leading causes of death. https://www.cdc.gov/nchs/fastats/leading-causes-of-death.htm However, nutrition can pose special challenges for the older adult. Chewing can be a problem if there are difficulties with dentition. Lack of oral care, missing teeth, or poorly fitting dentures can cause individuals to avoid intake of healthy foods. Regular dental care should be encouraged when working with older adults. Finances often impact nutritional intake when older adults have difficulty meeting their basic needs of housing, food, and health care. Additionally, the inability to plan, shop, and prepare meals because of activity intolerance, cognitive impairments, or physical limitations can impact nutrition. Nurses can initiate referrals to social workers or case managers for assistance with financial or health care concerns, as well as promote community resources such as Meals on Wheels or senior citizen meal site centers. Assisting individuals to meet their nutritional needs is an important aspect of health promotion. Physical Activity Physical activity is important throughout the life span. Older individuals may be limited in their ability to engage in physical activity due to various factors such as physical limitations, pain, and fear of falling. Musculoskeletal problems, such as impaired balance and arthritis, can impair an individual’s ability to walk or participate in regular exercise. Helping older adults find appropriate ways to maintain activity is an important nursing intervention. Nurses can advocate for the older adult by encouraging them to regularly attend health care checks with their provider and discuss concerns that limit their activity. They should be reassured that pain is not considered a normal part of aging and can be effectively treated so they can maintain physical activity comfortably. Safe Medication Use Because of the increased incidence of chronic disease, many older adults take multiple medications to manage their symptoms and conditions. Polypharmacy, the use of many medications, increases a person’s risk of adverse medication effects. Older adults may be prescribed medications by multiple providers, and they can become confused when attempting to safely manage their daily medication use. There are also changes in absorption, distribution, metabolism, and excretion of drugs as an individual ages that impact the safe use of any medications. The American Geriatrics Society maintains a list of medications to potentially avoid or use with caution in older adults because of the risk for harm. This list is called “AGS Beers Criteria.” Updated reports are published in the Journal of the American Geriatric Society. In addition to cautiously using medications listed on the ABG Beers Criteria list with older adults, nurses can promote other safety strategies with medications. For example, older adults should have all of their medications prescribed from multiple providers filled at the same pharmacy to check for interactions and replications. It is also helpful to use a daily pill dispenser to ensure medications are taken as prescribed. Nurses should also perform medication reconciliation during all clinic visits and on admission to health care agencies to review the patient’s current use of all medications. Psychosocial Well-Being As individuals age, they often experience loss of significant others, family members, and friends. These losses create increased risk for social isolation and depression. Poor mobility and transportation issues can also add to social isolation. As male older adults experience multiple losses, their risk for suicide increases.Centers for Disease Control and Prevention (n.d.) Injury Prevention and Control. https://www.cdc.gov/injury/index.html Nurses can provide information about community resources and outreach programs to promote social interaction for individuals experiencing isolation. Older adults experience risk for other safety issues, such as elder abuse and financial exploitation. Read more about safety considerations for older adults in the “Safety” chapter. Aging individuals continue to have sexual needs, and this aspect of their overall health should not be ignored. Assessment of these needs allows the nurse to integrate these aspects into the patient’s plan of care and make appropriate referrals when necessary. Adapting Patient Education As discussed throughout this chapter, there are many considerations when working with the older adult population and promoting optimal health and quality of life. It is also important to modify patient education methods depending on the individual’s knowledge, skills, and abilities. For example, some older adults readily engage in using electronic technology, but others have low digital literacy or experience difficulty when accessing electronic health resources. Nurses should adapt patient education to the needs of the individual and provide verbal, written, or electronic resources as needed, while considering any sensory, cognitive, or functional impairments. The ultimate goal of health promotion and patient education is to improve their understanding, motivation, and engagement in self-management and promote their quality of life. 19.4 Learning Activities Learning Activities (Answers to “Learning Activities” can be found in the “Answer Key” at the end of the book. Answers to interactive activity elements will be provided within the element as immediate feedback.) 1. Mr. Yang is an 87-year-old patient admitted to the medical surgical floor due to a recent fall at home. His wife reports that the patient has become increasingly frail and unsteady. Utilizing the SPICES tool, develop a list of assessment questions for Mr. Yang to determine potential problems and subsequent interventions. An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingfundamentals/?p=3701#h5p-95 XIX Glossary Ageism: Negative stereotypes of older individuals. Gerontology: The study of the social, cultural, psychological, cognitive, and biological aspects of aging. SPICES tool: Focuses on areas of common problems for aging individuals and can lead to early intervention and treatment. Answer Key XX Chapter 1 (Scope of Practice) Open Resources for Nursing (Open RN) Answer Key to Chapter 1 Learning Activities - When given instruction to titrate medications independently, the nursing student should recognize that this is outside of their scope of practice and training. The nursing student should inform the nurse that within the student role, they are not able to complete this action because it is outside of their practice scope. The nursing student should also report this instruction promptly to their instructor so that appropriate follow-up can be taken regarding re-education and review of the principles of safe delegation. - It is important to acknowledge that the conversation that is occurring in the breakroom is a violation of HIPAA. If a staff member is not involved in patient care, disclosure of patient care information is a violation of patient privacy and confidential health information. It is important to voice one’s concern regarding the disclosure of private health information and remind all staff of the importance of adherence to HIPAA requirements within a health care setting. Answers to interactive elements are given within the interactive element. Chapter 2 (Communication) Open Resources for Nursing (Open RN) Answer Key to Chapter 2 Learning Activities 2. It is important to take action to limit the distractions within the environment when communicating with Mr. Curtis. Upon entry into the room and initial discussion, it would be helpful to identify a few key family members who might contribute to the admission history and excuse the others for a short period of time. Additionally, it is important prior to beginning an interaction that Mr. Curtis consent to discuss admission details in front of the family members who are present. Other factors to consider include limitation to noise distraction within the environment. For example, closing the door to the hallway and turning off the television may be helpful. If Mr. Curtis uses any assistive devices, such as hearing aids or eye glasses, these should also be encouraged. Finally, it is important that the nurse consider strategies to enhance communication. Sitting across from Mr. Curtis, making eye contact, and creating an open, approachable, nonhurried demeanor can help to facilitate the information exchange. Answers to interactive elements are given within the interactive element. Chapter 3 (Diverse Patients) Open Resources for Nursing (Open RN) Answer Key to Chapter 3 Learning Activities 2. It is important to demonstrate professional respect for a patient’s cultural beliefs, background, and practices when providing care. You can ensure appropriate actions are taken by introducing yourself with name and role, asking preference on how the individual would like to be addressed, attending to personal space of the patient, following patient and family lead for eye contact behaviors, using inclusive language, etc. It is important to note the patient’s language of preference and enact interpreter services if a communication barrier is noted. Additionally, it is important to be honest regarding individual level of understanding about one’s cultural beliefs. Ask polite questions and seek clarification to avoid misunderstanding. Answers to interactive elements are given within the interactive element. Chapter 4 (Nursing Process) Open Resources for Nursing (Open RN) Answer Key to Chapter 4 Learning Activities Box 4: Scenario C: Subjective data: “I am so short of breath.” “My ankles are so swollen.” “I am so tired and weak that I can’t get out of the house to go grocery shopping.” “I get so dizzy.” Objective data: Bilateral basilar crackles in the lungs Bilateral 2+ pitting edema of the ankles and feet Increase weight of 10 pounds Furosemide use (a medication that eliminates excess fluid from the body) Oxygen saturation 91% on room air Secondary data: Daughter reports, “We are so worried about mom living at home by herself when she is so tired all the time!” Care Plan Activity Answers: The client, Mark S., is a 57-year-old male who was admitted to the hospital with “severe” abdominal pain that was unable to be managed in the Emergency Department. The physician has informed Mark that he will need to undergo some diagnostic tests. The tests are scheduled for the morning. After receiving the news about his condition and the need for diagnostic tests, Mark begins to pace the floor. He continues to pace constantly. He keeps asking the nurse the same question (“How long will the tests take?”) about his tests over and over again. The patient also remarked, “I’m so uptight I will never be able to sleep tonight.” The nurse observes that the client avoids eye contact during their interactions and that he continually fidgets with the call light. His eyes keep darting around the room. He appears tense and has a strained expression on his face. He states, “My mouth is so dry.” The nurse observes his vital signs to be: Temperature 98 degrees F, Pulse 104, Respiratory Rate 30, Blood Pressure 180/96. The nurse notes that his skin is diaphoretic and cool to the touch. 1. Group (cluster) the objective and subjective data. Objective Data: - 57 years old - Paces the floor - Avoids eye contact - Fidgets with call light - Eyes dart around room - Temp 98 degrees F - Pulse 104 - Blood pressure 180/96 - He is diaphoretic - Skin is cool to touch Subjective Data: - Male - Severe abdominal pain - “I’m so uptight that I will never be able to sleep tonight.” - Appears tense - Strained expression on his face - “My mouth is so dry.” *Note that “male” is subjective data in this case because the patient identifies as a male and reports that he is a male. 2. Create a problem-focused nursing diagnosis (hypothesis). Anxiety related to need for diagnostic testing as manifested by increased heart rate, pacing the floor, avoiding eye contact, diaphoretic and cool to the touch skin, appearing tense, dry mouth, “I’m so uptight I will never be able to sleep tonight.” This is an actual nursing diagnosis because the patient is experiencing and exhibiting symptoms of anxiety. 3. Develop a broad goal and identify an expected outcome in “SMART” format. Goal: The patient will have reduced anxiety. Expected Outcome in SMART format: The patient will verbalize effective coping mechanisms to decrease his feelings of anxiety in the next two hours. 4. Outline three interventions for the nursing diagnosis. Cite an evidence-based source. Potential interventions include: - Use a calm, reassuring approach. - Explain all procedures, including sensations likely to be experienced during the procedure. - Seek to understand the patient’s perspective of a stressful situation. - Provide factual information concerning diagnosis, treatment, and prognosis. - Encourage verbalization of feelings, perceptions, and fears. - Provide diversional activities geared toward the reduction of tension. - Control stimuli, as appropriate, for patient needs. - Instruct the patient on the use of relaxation techniques. - Administer prescribed medications to reduce anxiety as appropriate. Source: Ackley, B., Ladwig, G., Makic, M. B., Martinez-Kratz, M., & Zanotti, M. (2020). Nursing diagnosis handbook: An evidence-based guide to planning care (12th ed.). Elsevier, pp. 144-147. 5. Imagine that you implemented the interventions you identified. Evaluate the degree to which the expected outcome was achieved. The patient verbalized effective coping mechanisms to decrease anxiety in the next two hours. Outcome was met. Answers to interactive elements are given within the interactive element. Chapter 5 (Safety) Open Resources for Nursing (Open RN) Answer Key to Chapter 5 Learning Activities 1. Risk factors: hip fracture, morphine pain medication, diminished eyesight and hearing, ambulates with walker, weakness, experience of recent fall. 2. Morse Fall Risk Assessment Scoring: - History of fall – 25 - Walker – 15 - Weak Gait -10 - Total: 50 – High Risk 3. Interventions to address risk factors: - Provide adequate lighting and night-light - Use of half rails - Encourage rest - Place articles within reach at bedside - Use elevated toilet seat in bathroom - Use assistive devices, glasses and hearing aids - Obtain orthostatic blood pressures - Wear shoes or slippers with non-skid soles 4. Potential response: “Mr. Moore, your safety is most important and we need to ensure you do not fall. If you have a bowel movement, we will clean it up. Moving forward, it may be helpful for us to have a commode chair closer to your bedside so we do not need to travel so far if urgency arises.” Answers to interactive elements are given within the interactive element. Chapter 6 (Cognitive Impairments) Open Resources for Nursing (Open RN) Answer Key to Chapter 6 Learning Activities Scenario A 1. In the immediate postoperative period, it is important to assess for signs of infection, electrolyte imbalances, confusion related to new medications, and hypoxia. 2. Table 1 \| Dementia \| Delirium \| Depression \| \| \|---\|---\|---\|---\| \| Onset \| Vague, insidious onset; symptoms progress slowly \| Sudden onset over hours and days with fluctuations \| Onset often rapid with identifiable trigger or life event such as bereavement \| \| Symptoms \| Symptoms may go unnoticed for years. May attempt to hide cognitive problems or may be unaware of them. Often disoriented to time, place, and person. Impaired short-term memory and information processing. Confusion is often worse in the evening (sundowning) \| Often disoriented to time, place, and person. Impaired short-term memory loss and information processing. Confusion is often worse in the evening \| Obvious at early stages and often worse in the morning. Can include subjective complaints of memory loss \| \| Consciousness \| Normal \| Impaired attention/alertness \| Normal \| \| Mental State \| Possibly labile mood. Consistently decreased cognitive performance \| Emotional lability with anxiety, fear, depression, aggression. Variable cognitive performance \| Distressed/unhappy. Variable cognitive performance \| \| Delusions/Hallucinations \| Common \| Common \| Rare \| \| Psychomotor Disturbance \| Psychomotor disturbance in later stages \| Psychomotor disturbance present – hyperactive, purposeless, or apathetic \| Slowed psychomotor status in severe depression \| Based upon the patient’s sudden exacerbation of symptoms, she would most likely be exhibiting signs of delirium related to her recent surgery. 3. Interventions include the following: - Control the environment. Make sure that the room is quiet and well-lit, have clocks or calendars in view, and encourage family members to visit. - Administer prescribed medications, including those that control aggression or agitation and pain relievers if there is pain. - Ensure the patient has their glasses, hearing aids, or other assistive devices for communication in place. Lack of assistive sensory devices can worsen delirium. - Avoid sedatives. Sedatives can worsen delirium. - Assign the same staff for patient care when possible. Scenario B 1. Symptoms of moderate Alzheimer’s disease include the following: - Require assistance with reminders to eat, wash, and use the restroom. - Lack of recognition of family and friends. - Behavioral symptoms such as wandering, getting lost, hallucinations, delusions, and repetitive behavior may occur. - Patients living at home may engage in risky behavior, such as leaving the house in clothing inappropriate for weather conditions or leaving on the stove burners. 2. Additional assessments would include assessing for signs of physical discomfort, changes in the environment that may be contributing to the increased anxiety or confusion, and communication pattern. 3. Strategies for therapeutic response: - Back off and ask permission before performing care tasks. Use calm, positive statements, slow down, add lighting, and provide reassurance. Offer guided choices between two options when possible. Focus on pleasant events and try to limit stimulation. - Use effective language. When speaking, try phrases such as, “May I help you? Do you have time to help me? You’re safe here. Everything is under control. I apologize. I’m sorry that you are upset. I know it’s hard. I will stay with you until you feel better.” - Listen to the person’s frustration. Find out what may be causing the agitation, and try to understand. - Check yourself. Do not raise your voice, show alarm or offense, or corner, crowd, restrain, criticize, ignore, or argue with the person. Take care not to make sudden movements out of the person’s view. 4. Medications may include the following: - Donepezil (Aricept), approved to treat all stages of Alzheimer’s disease - Galantamine (Razadyne), approved for mild-to-moderate stages - Rivastigmine (Exelon), approved for mild-to-moderate stages - Memantine (Namenda) and a combination of memantine and donepezil (Namzaric) are by approved the FDA for treatment of moderate to severe Alzheimer’s. Answers to interactive elements are given within the interactive element. Chapter 7 (Sensory Impairments) Open Resources for Nursing (Open RN) Answer Key to Chapter 7 Learning Activities - Answers to “Activity 1” will be individualized based on the assessment findings that are identified in the data collection with your student peer or simulated patient. Answers to interactive elements are given within the interactive element. Chapter 8 (Oxygenation) Open Resources for Nursing (Open RN) Answer Key to Chapter 8 Learning Activities - Potential interventions to improve breathing pattern and lung capacity include coughing and deep breathing, use of an incentive spirometer, use of an acapella flutter valve to mobilize secretions, increased fluids to thin secretions, frequent ambulation to mobilize secretions, etc. Answers to interactive elements are given within the interactive element. Chapter 9 (Infection) Open Resources for Nursing (Open RN) Answer Key to Chapter 9 Learning Activities - Based upon Ms. Jamison’s current vital signs and presenting condition, one would suspect the patient is septic. Her current vital signs reflect an elevated temperature > 100.4 and a tachycardic heart rate. Additionally, based upon the patient’s history, one would suspect she has an unresolved urinary tract infection. Answers to interactive elements are given within the interactive element. Chapter 10 (Integumentary) Open Resources for Nursing (Open RN) Answer Key to Chapter 10 Learning Activities - It would be helpful to assess the sacral area to identify the stage the pressure injury. It would also be helpful to assess Mr. Johns’ albumin level to properly identify nutritional inadequacies and protein levels for wound healing. - Individual factors that increase vulnerability to pressure injury development include weakness, diminished sensation (related to his stroke), diminished mobility, frequent incontinence, decreased nutritional intake, etc. Answers to interactive elements are given within the interactive element. Chapter 11 (Comfort) Open Resources for Nursing (Open RN) Answer Key to Chapter 11 Learning Activities Patient Scenario Colon Cancer & Pain Management 1. What additional assessments (subjective and objective) will you perform on Joe? Additional assessments include a full respiratory, abdominal, and pain assessment. It is important to include Joe’s subjective statements related to these systems, as well as observable findings. It would be important to collect information related to lung sounds, observed breathing effort, color of sputum, reports of shortness of breath, etc. Additionally, the patient should be assessed for guarding, grimace, self-report of pain, etc. The patient may not be getting out of bed and ambulating due to pain, but the lack of ambulation is causing additional problems for the patient. With the colon resection and lack of ambulation, it would also be important to determine the patient’s bowel function. Abdominal sounds, ability to pass flatus, last bowel movement, signs of nausea, etc., are all important for determining bowel motility. 2. List the top three priority nursing diagnoses for Joe. Potential priority diagnoses for Joe might include the following: - Ineffective Breathing Pattern - Acute Pain - Impaired Mobility - Activity Intolerance - Constipation 3. Joe states, “I don’t want to use morphine. I am afraid I will become addicted to it like my friend did after he came home from the war.” How will you respond to therapeutically address his concerns, yet also teach Joe about good pain management? It would be important to dispel myths for the patient regarding pain management and addiction. Joe should receive education that the use of opioids is appropriate for the treatment of acute surgical pain in the short-term. He should receive instruction that by omitting the use of pain medications, his pain response has led to decreased mobility, which is causing respiratory complications for him. 4. What are common side effects of opioids and how will you plan to manage these side effects for Joe? Common side effects of opioids are decreased respiratory rate, decreased bowel motility, increased lethargy, etc. Of significant concern for Joe is the potential impact of the opioid on his bowel function. The surgical intervention and lack of mobility have already placed him at risk for constipation. It will be important for the patient to resume a sufficient bowel regimen with adequate fluids, ambulation, stool softeners, high fiber foods, and laxatives if needed. 5. Emotional issues could also be affecting Joe’s perception of pain. What will you further physically assess and therapeutically address? With Joe’s diagnosis of colon cancer, there can be many personal coping challenges that the patient is experiencing. It is important to encourage Joe to verbalize his feelings related to his diagnosis and understand what resources might best help facilitate his individual coping. 6. After providing patient education about morphine and the PCA pump, you check on Joe later in the day and notice he has had five injections and 15 attempts in the past hour. What further assessments will you perform? It will be important to assess the insertion site where the pain medication is infusing to be certain that the tubing is not kinked and that the medication is actually reaching the patient. Additionally, Joe should receive education about use of the pump and guidelines regarding self-administration to ensure he understands the administration parameters appropriately. He should also have a thorough pain assessment completed, and the nurse should collect information to report to the prescribing physician regarding the use of medication and patient response. Answers to interactive elements are given within the interactive element. Chapter 12 (Sleep and Rest) Open Resources for Nursing (Open RN) Answer Key to Chapter 12 Learning Activities Scenario A A nurse is caring for a patient who has been hospitalized after undergoing hip-replacement surgery. The patient complains of not sleeping well and feels very drowsy during the day. 1. The patient may be experiencing pain that is disrupting the sleep pattern. Additionally, the inpatient hospital settings may present unintended interruptions such as assessment and vital sign collection. Measures should be taken to create a quiet, therapeutic environment and minimize interruptions during sleeping hours. 2. The nurse should assess the patient’s pain level, general comfort, and self-reported feeling of restfulness upon awakening. The nurse should also carefully examine the patient’s rest pattern by asking questions regarding length of rest, period of wakefulness, and intervals with which these occur throughout the day. 3. The patient will have uninterrupted rest of six hours each night during their hospitalization. 4. The nurse should consider pain medication intervention and strategies to create a therapeutic and restful environment. This includes minimizing interruption overnight, clustering care and interventions, limiting noise or distractions, etc. The nurse should also consider if sleep aids are needed while being mindful of the impact of these medication aids in relation to fall risk. The nurse should also take measures to advocate for quiet periods for the patient. 5. The nurse would determine the effectiveness of interventions by monitoring the patient’s level of alertness throughout the daytime hours, self-reported level of energy, and ability to participate in therapy and care activities. Scenario B A nurse is assigned to work rotating shifts and develops difficulty sleeping. 1. Rotating shifts impact an individual’s sleep pattern because of the disruption to one’s circadian rhythm. 2. Symptoms of insomnia include lying awake for a long time before falling asleep, sleeping for only short periods, waking up too early in the morning and not being able to get back to sleep, waking up feeling unrested, difficulty focusing on tasks, irritability, anxiousness, and depression. 3. Healthy sleep habits include the following: - Sleep in a cool, quiet place. Avoid artificial light from the TV or electronic devices, as this can disrupt your sleep-wake cycle. - Go to sleep and wake up around the same times each day, even on the weekends. If you can, avoid night shifts, irregular schedules, or other things that may disrupt your sleep schedule. - Avoid caffeine, nicotine, and alcohol close to bedtime. - Get regular physical activity during the daytime (at least 5 to 6 hours before going to bed). - Avoid daytime naps, especially in the afternoon. - Eat meals on a regular schedule and avoid late-night dinners to maintain a regular sleep-wake cycle. - Limit how much fluid you drink close to bedtime. - Learn new ways to manage stress. - Avoid certain over-the-counter and prescription medicines that can disrupt sleep (for example, some cold and allergy medicines). Answers to interactive elements are given within the interactive element. Chapter 13 (Mobility) Open Resources for Nursing (Open RN) Answer Key to Chapter 13 Learning Activities - The nurse should perform a comprehensive pain assessment using a framework such as “PQRST” or “OLDCARTES” and treat Ms. Curtis’ pain according to assessment findings. The nurse should use therapeutic communication techniques to determine why the patient is refusing to attend physical therapy. For example, the nurse could ask, “Can you help me understand the reasons why you have not attended your previous physical therapy appointments,” keeping in mind that pain and fear of falling are common causes. It is often helpful to pre-medicate the patient with analgesics before attending physical therapy. If currently prescribed medications are not effective, the provider should be notified. - Ms. Curtis is at risk for complications of immobility, pneumonia, deep vein thrombosis, constipation, and skin breakdown. The nurse should assess for signs of these complications, as well as educate the patient regarding signs to report. - A SMART outcome (established with Ms. Curtis) could be, “The patient will attend the next scheduled physical therapy appointment and report effective pain management during and after the session.” - The nurse will monitor the patient’s pain level using a pain intensity scale one hour prior to physical therapy and administer prescribed medications according to current pain level and anticipated pain level. The nurse will use therapeutic communication to determine the patient’s causes for declining physical therapy appointments and plan interventions accordingly. The nurse will encourage rest before and after physical therapy appointments. The nurse will encourage coughing and deep breathing to prevent pneumonia and range of motion exercises while in bed or sitting to prevent deep vein thrombosis. The nurse will perform hourly rounding to encourage repositioning to prevent skin breakdown. The nurse will encourage fiber and fluids to prevent constipation. - The nurse will evaluate if interventions were successful by referring to the established SMART outcome and monitoring if the patient attends the next scheduled physical therapy appointment and if pain was effectively managed during the session. Answers to interactive elements are given within the interactive element. Chapter 14 (Nutrition) Open Resources for Nursing (Open RN) Answer Key to Chapter 14 Learning Activities Scenario 1 - It would be important to assess Mr. Jones’s swallowing, bowel sounds, ability to pass flatus, abdominal distention, and any complaints of nausea. - When transitioning the patient from NPO status, the patient would be started on clear liquids to ensure dietary tolerance prior to progression toward solid foods. Scenario 2 - Mrs. Casey’s BMI is 15, placing her in the “Underweight” category since it is below 18.5. - Mrs. Magnesium levels may be low due to intake or can also be caused by excessive alcohol intake. - The nurse should perform a general survey on Mrs. Casey, paying close attention to her energy level and mobility deficits as a result of the stroke. The nurse should ask Mrs. Casey about her typical 24-hour food intake, appetite, food allergies, and food shopping and preparation activities. - Imbalanced Nutrition: Less than Body Requirements related to insufficient dietary intake as evidenced by BMI 15 and albumin level 10 g/mL. - Mrs. Casey’s BMI will increase to at least 16 in the next month with a continued upward trend. - The nurse will contact the provider and request a referral for a dietician. The nurse will contact the facility’s social worker regarding promoting nutritional intake with Meals on Wheels and other services. The nurse will monitor food/fluid ingested daily and caloric intake in collaboration with the dietician and encourage nutritional supplements as prescribed. The nurse will encourage the patient to select or order preferred foods for mealtimes. The nurse will ensure that oral care is performed before meals and that foods are presented in an attractive, pleasing manner. The patient will be placed in a seated position before eating, the meal tray set up, and assistance provided according to the patient’s needs. - The nurse will evaluate the effectiveness of interventions by monitoring the patient’s weekly weights and assessing if her BMI is trending upward according to the previously established SMART goal. Answers to interactive elements are given within the interactive element. Chapter 15 (Fluids & Electrolytes) Open Resources for Nursing (Open RN) Answer Key to Chapter 15 Learning Activities Scenario A Answer Key: - Interpret Mr. Smith’s ABG result on admission. The pH is low indicating acidosis. The elevated PaCO2 indicates respiratory acidosis, and the normal HCO3 level indicates is it uncompensated respiratory acidosis. - Explain the likely cause of the ABG results. The exacerbation of heart failure is likely causing fluid in his alveoli, decreasing ventilation, and causing the retention of carbon dioxide and decreased oxygenation. - Create a nursing diagnosis for Mr. Smith’s fluid status in PES format based on his admission data: Excess Fluid Volume related to excessive fluid intake as evidenced by adventitious breath sounds, edema, and weight gain of 15 pounds over a short period of time. - What is Mr. Smith’s fluid balance this morning? Support your answer with data. He is demonstrating Deficient Fluid Volume as evidenced by the following signs and symptoms: feeling thirsty and dizzy, having low systolic blood pressure and elevated heart rate and respiratory rate, and lab work showing elevated serum sodium and BUN results. - What is the probably cause of his fluid balance? Excessive IV diuretics are likely causing dehydration. - Interpret Mr. Smith’s lab results. What are the potential causes of these results? In addition to the lab results indicating fluid volume deficit explained in Answer 4, he is also demonstrating hypokalemia that is likely caused by the diuretics. His creatinine is also elevated, which could indicate kidney disease. - Create a nursing diagnosis statement in PES format for Mr. Smith’s current fluid status: Deficient Fluid Volume related to insufficient fluid intake as evidenced by alteration in mental status, decreased blood pressure, increased heart rate, thirst, and sudden weight loss. - Create a new expected outcome in SMART format for Mr. Smith: Mr. Smith will demonstrate fluid balance within 24 hours as evidenced by moist mucus membranes and 24-hour intake and output balance. - In addition to providing intravenous fluids, what additional interventions will you implement for Mr. Smith? Additional interventions include weigh daily, monitor intake and output every four hours, provide fresh water and fluids preferred by the patient, administer oral potassium replacements as ordered, and monitor for signs of fluid volume excess while receiving IV fluids. - How will you evaluate if the nursing interventions are effective? As stated in the SMART outcome, the nurse will evaluate for moist mucus membranes and balanced intake and output in 24 hours. Scenario B Answer Key: 1. What is Mr. M.’s fluid balance? Provide data supporting the imbalance. Mr. M. is exhibiting Deficient Fluid Volume. His blood pressure is decreased and his heart rate is tachycardic. His serum osmolarity, hematocrit, urine specific gravity, and BUN are elevated. 2. What is your interpretation of Mr. M.’s ABGs? Step 1: pH 7.30 is below 7.35, so it is acidic and abnormal. We know this will be an acidosis. Step 2: PaCO2 50. This is above 45, so it is acidic. The PaCO2 is moving in the opposite direction of the pH, so we know this will be respiratory in nature. This is called Respiratory Acidosis. Step 3: HCO3 24. This is a normal HCO3 level so we know the problem is not metabolic in nature. We also know the kidneys are not trying to compensate for the lung problems. Step 4: Compensation: The pH is abnormal, so there is not complete compensation. The HCO3 is normal, so the kidneys are not trying to compensate for the lungs. We call this uncompensated. Interpretation: Uncompensated Respiratory Acidosis 3. What is your interpretation of Mr. M.’s electrolyte studies? Potassium: 5.9 – elevated, most likely due to acidosis occurring Magnesium: 1.0 – low, most likely due to alcoholism or inadequate nutrition Calcium: 10.2 – elevated, most likely due to acidosis occurring Sodium: 137 – normal 4. Is Mr. M. stable or unstable? Why? Mr. M. is unstable. He is hypotensive and tachycardic. Also, his respiratory rate is low and labored, and O2 saturations are quite low. His acid-base balance is quite abnormal. He is developing hypovolemic shock and could experience cardiac and respiratory arrest if not treated emergently. 5. For what complications will you monitor? Mr. M. could have a respiratory arrest due to his severe acidosis, decreased level of consciousness, and respiratory distress. The elevated potassium and decreased magnesium put Mr. M. at risk for cardiac arrhythmias. His elevated calcium level could cause nausea and vomiting, which puts him at risk for aspiration with his associated lethargy. 6. Write an SBAR communication you would have with the health care provider to notify them about Mr. M.’s condition. S: Hi, Dr. X. This is ________, a nursing student working with Mr. M. This morning Mr. M. is lethargic and having labored respirations. B: Mr. M. was admitted during the night with pneumonia. He has a history of alcohol abuse and coronary artery disease. A: Mr. M.’s vital signs are the following: BP 80/45, HR 110, RR 8, O2 saturation 80% on 3 L/NC. He has coarse crackles throughout his lung fields, and he is using accessory muscles to breathe. Mr. M. is lethargic and having difficulty following commands. R: I am concerned that Mr. M.’s respiratory status is declining. I recommend increasing his oxygen and checking arterial blood gasses and electrolyte studies. I also would like you to come see Mr. M. 7. Create a NANDA-I diagnosis for Mr. M. in PES format. Fluid Volume Deficit related to insufficient fluid intake as evidenced by BP 80/45, HR 110, and elevated serum osmolarity, hematocrit, BUN, and urine specific gravity results. 8. Identify an expected outcome for Mr. M. in SMART format. Mr. M. will demonstrate improving fluid balance as demonstrated by blood pressure and heart rate returning within normal range within 8 hours. 9. What interventions will you plan for Mr. M.? Mr. M. will need either a BiPAP or intubation and mechanical ventilation for his respiratory status. He will need magnesium supplementation, and his calcium and potassium will need to be monitored closely. He may need insulin to help decrease his potassium. Any potassium contained in IV fluids should be stopped to prevent further potassium buildup. He will also need antibiotics for his pneumonia and IV fluids to treat his hypotension and tachycardia. 10. How will you evaluate if your interventions are effective? Based on the SMART goal established, the nurse will monitor Mr. M.’s blood pressure and heart rate and evaluate if they have returned to normal within 8 hours. Additionally, the ABGs for Mr. M. should return to closer to normal. He will show improvement with his level of consciousness. Magnesium levels will return to normal. As Mr. M.’s pH normalizes, the calcium and potassium levels should return to normal. Mr. M.’s fever should subside and his vital signs should return to normal as the infection is treated and IV fluids are given. 11. Write a nursing note about Mr. M.’s condition and your actions taken. This can be in the form of a DAR, SOAP, or summary nursing note. 01/31/20xx 0900 D: On morning assessment, pt noted to be lethargic, unable to follow commands consistently, and using accessory muscles with breathing. Coarse crackles noted throughout lung fields. VS are BP 80/45, HR 110, RR 8, O2 sat 80% on 3L per nasal cannula, and temp 38.1 C. A: Dr. X. notified and orders rec’d to increase O2 to 10L per non-rebreather mask and to check electrolytes and ABGs. R: O2 increased and labs drawn and resulted as follows: pH 7.30, PaCO2 50, PaO2 59, HCO3 24, SaO2 80. Potassium 5.9, Magnesium 1.0, Calcium 10.2, Sodium 137. Will continue to monitor patient closely and will update Dr. X. of changes. ________,SN Answers to interactive elements are given within the interactive element. Chapter 16 (Elimination) Open Resources for Nursing (Open RN) Answer Key to Chapter 16 Learning Activities 1. Mrs. Gonzalez should be offered therapeutic reassurance that although urinary incontinence can be the result of aging, there are interventions that can be helpful. These include pelvic muscle exercises, timed voiding to assist in regaining bladder control, avoidance of triggering agents such as caffeine, weight control, and avoidance of heavy lifting, etc. Additional medical intervention may include biofeedback sensors, pessaries, anticholinergic medications, or surgical intervention. The patient should also be educated on protective products that can help protect the skin from breakdown and assist with odor control. Answers to interactive elements are given within the interactive element. Chapter 17 (Grief and Loss) Open Resources for Nursing (Open RN) Answer Key to Chapter 17 Learning Activities Scenario A 1. What actions should the nurse take to support Mr. Lyn? The grieving process is variable for every individual. Mr. Lyn’s outward expression of grief should be supported by the nurse. The nurse can assist Mr. Lyn to cope by using supportive presence and encouraging reminiscence by sharing good memories of his life with Mrs. Lyn. It is helpful to offer the services of the agency chaplain, as well as to offer prayer and spiritual support based on Mr. Lyn’s beliefs and the nurse’s comfort level. The nurse can also encourage Mr. Lyn to contact other family members and friends for additional social support. 2. What medication is helpful to administer to treat dyspnea at end of life? Roxanol, a highly concentrated solution of morphine, can be administered sublingually as ordered for pain and air hunger. 3. Mr. Lyn tells the nurse, “My daughter lives six hours away and would like to be here when the time comes. How much longer does she have to live?” What is the nurse’s best response? Although we never know exactly when death will occur, there are recognizable signs that occur as death becomes imminent, such as noisy or irregular breathing, increased lethargy, and a type of bruising called “mottling.” Mrs. Lyn is demonstrating new changes in her breathing status, so death may occur in the next few days. 4. The daughter arrives and seems hesitant to talk to or touch the patient. What tasks can the nurse coach family members to do at the end of a patient’s life? Nurses can encourage family members to talk with and touch their loved one. They can encourage family members to reminisce about happy stories and say “I love you” or say “Goodbye.” 5. Mrs. Lyn dies the following evening. What postmortem care should the nurse provide? After verifying the lack of an apical heartbeat for a full minute, the nurse should follow agency policy regarding notifications and postmortem care. The nurse should document the date and time of assessment, the physician contacted, the individuals present at the time of death, the lack of response to stimuli and absence of an apical pulse, and the arrangements for transport to the morgue or funeral home. Typically, the patient is bathed, dressed, and positioned to show respect and provide dignity. Cultural practices should be honored. The nurse can offer to contact other family members to inform them of the death and support families in their ways of saying goodbye. Scenario B - According to Kubler-Ross’ theory of grief/loss, what stage of grief is Terry currently experiencing? Terry is demonstrating the stage of denial according to Kubler-Ross’ theory of grief/loss. - How would you explain palliative care to him? Palliative care is a way to manage your symptoms and optimize your quality of life. A team will assist you in making difficult decisions and can provide support to you and your family members - How would you explain advance directives to him? Advance directives are a legal way for you to establish your wishes for health care. A living will is a document that you can complete that describes your wishes if you are no longer able to speak for yourself. For example, you can decide if you would ever want a feeding tube placed if you are no longer able to eat. You can also identify a health care power of attorney who will serve as your decision maker when you can no longer speak for yourself. Would you like me to ask a social worker to visit so you can talk more about these options? - Identify a SMART outcome. “Terry will discuss the meaning of the cancer diagnosis to his life before discharge.” - List sample nursing interventions that may help Terry to cope with this new diagnosis. Use a calm, reassuring approach. Provide an atmosphere of acceptance. Seek to understand the patient’s perspective. Provide Terry realistic choices about aspects of his care when possible. Encourage verbalization of feelings, perceptions, and fears. Encourage support from family and friends. Answers to interactive elements are given within the interactive element. Chapter 18 (Spirituality) Open Resources for Nursing (Open RN) Answer Key to Chapter 18 Learning Activities 1. These questions can be asked to gain insight into the patient’s personal spiritual beliefs: F–Faith or beliefs: What are your spiritual beliefs? Do you consider yourself spiritual? What things do you believe in that give meaning to life? I–Importance and influence: Is faith/spirituality important to you? How has your illness and/or hospitalization affected your personal practices /beliefs? C–Community: Are you connected with a faith center in the community? Does it provide support/comfort for you during times of stress? Is there a person/group/leader who supports/assists you in your spirituality? A–Address: What support can we provide to support your spiritual beliefs/practices? Answers to interactive elements are given within the interactive element. Chapter 19 (Care of the Older Adult) Answer Key to Chapter 19 Learning Activities The SPICES tool can assess many common problems for aging adults. S: Sleep Disorders Examples of questions might include the following: What length of rest periods do you have during the night? Do you rise frequently? How many times per night? Do you nap during the day? Where do you sleep? P: Problems with Eating or Feeding Examples of questions might include the following: Do you notice difficulty swallowing foods or beverages? Do you choke after swallowing? Do you ever experience a sensation of food being caught in the throat? I: Incontinence Examples of questions might include the following: Do you experience frequent urination? Do you feel a sense of urgency or that you will not reach the bathroom in time to void? Do you feel that you are able to empty your bladder completely? C: Confusion Examples of questions might include the following: Who are you? Where are you? Who is the President? Do you ever experience difficulty remembering why you entered a certain room? Do you find yourself forgetting things or people you previously knew? Do your loved ones report that you have memory issues? E: Evidence of Falls Examples of questions might include the following: Have you experienced a recent fall? What are the bruises on your arms or legs attributed to? Do you feel unsteady or stumble when first arising out of bed? S: Skin Breakdown Examples of questions might include the following: Do you have any open areas on your skin? Do you have areas of redness that do not go away? Are you able to reposition yourself frequently or do you rely on the assistance of others? Answers to interactive elements are given within the interactive element. Appendix A: Sample NANDA-I Diagnoses 1 Open Resources for Nursing (Open RN) Table A contains commonly used NANDA-I nursing diagnoses categorized by domain. Many of these concepts will be further discussed in various chapters of this book. Nursing students may use Gordon’s Functional Health Patterns framework to cluster assessment data by domain and then select appropriate NANDA-I nursing diagnoses. For more information, refer to a nursing care planning resource. Table A Sample NANDA-I Diagnoses by DomainHerdman, T. H., & Kamitsuru, S. (Eds.). (2018). Nursing diagnoses: Definitions and classification, 2018-2020. Thieme Publishers New York. \| Domain \| Class & Nursing Diagnosis \| \|---\|---\| \| Health Promotion \| Health Awareness Health Management \| \| Nutrition \| Ingestion Metabolism Hydration \| \| Elimination and Exchange \| Urinary function Gastrointestinal function Respiratory function \| \| Activity/Rest \| Sleep/Rest Activity/Rest Energy balance Cardiovascular/Pulmonary responses Self-care \| \| Perception/Cognition \| Attention Cognition Communication \| \| Self-Perception \| Self-concept Self-esteem Body image \| \| Role Relationship \| Caregiving roles Family relationships Role performance \| \| Sexuality \| Sexual function \| \| Coping/Stress Tolerance \| Post-trauma responses Coping responses Neurobehavioral stress \| \| Life Principles \| \| \| Safety/Protection \| Infection Physical injury Violence Environmental hazards Defensive processes Thermoregulation \| \| Comfort \| Physical comfort Social comfort \| \| Growth/Development \| \| Appendix B: Template for Creating a Nursing Care Plan 2 Open Resources for Nursing (Open RN) Template for Creating a Nursing Care Plan Appendix C: Sample Abbreviated Care Plan for Scenario C 3 Open Resources for Nursing (Open RN) Sample Abbreviated Care Plan for Scenario C	302,907	common-pile/pressbooks_filtered	https://ecampusontario.pressbooks.pub/mohawkcollegenursingpharmacology/chapter/nursing-fundamentals/	pressbooks	pressbooks-0000.json.gz:64003	https://ecampusontario.pressbooks.pub/mohawkcollegenursingpharmacology/chapter/nursing-fundamentals/
Yl2dj5r0rcBYGwLG	Atoms First / OpenStax	107 Catalysis [latexpage] Learning Objectives By the end of this section, you will be able to: - Explain the function of a catalyst in terms of reaction mechanisms and potential energy diagrams - List examples of catalysis in natural and industrial processes Catalysts Do Not Affect Equilibrium A catalyst can speed up the rate of a reaction. Though this increase in reaction rate may cause a system to reach equilibrium more quickly (by speeding up the forward and reverse reactions), a catalyst has no effect on the value of an equilibrium constant nor on equilibrium concentrations. The interplay of changes in concentration or pressure, temperature, and the lack of an influence of a catalyst on a chemical equilibrium is illustrated in the industrial synthesis of ammonia from nitrogen and hydrogen according to the equation A large quantity of ammonia is manufactured by this reaction. Each year, ammonia is among the top 10 chemicals, by mass, manufactured in the world. About 2 billion pounds are manufactured in the United States each year. Ammonia plays a vital role in our global economy. It is used in the production of fertilizers and is, itself, an important fertilizer for the growth of corn, cotton, and other crops. Large quantities of ammonia are converted to nitric acid, which plays an important role in the production of fertilizers, explosives, plastics, dyes, and fibers, and is also used in the steel industry. In the early 20th century, German chemist Fritz Haber ((Figure)) developed a practical process for converting diatomic nitrogen, which cannot be used by plants as a nutrient, to ammonia, a form of nitrogen that is easiest for plants to absorb. The availability of nitrogen is a strong limiting factor to the growth of plants. Despite accounting for 78% of air, diatomic nitrogen (N2) is nutritionally unavailable due the tremendous stability of the nitrogen-nitrogen triple bond. For plants to use atmospheric nitrogen, the nitrogen must be converted to a more bioavailable form (this conversion is called nitrogen fixation). Haber was born in Breslau, Prussia (presently Wroclaw, Poland) in December 1868. He went on to study chemistry and, while at the University of Karlsruhe, he developed what would later be known as the Haber process: the catalytic formation of ammonia from hydrogen and atmospheric nitrogen under high temperatures and pressures. For this work, Haber was awarded the 1918 Nobel Prize in Chemistry for synthesis of ammonia from its elements. The Haber process was a boon to agriculture, as it allowed the production of fertilizers to no longer be dependent on mined feed stocks such as sodium nitrate. Currently, the annual production of synthetic nitrogen fertilizers exceeds 100 million tons and synthetic fertilizer production has increased the number of humans that arable land can support from 1.9 persons per hectare in 1908 to 4.3 in 2008. In addition to his work in ammonia production, Haber is also remembered by history as one of the fathers of chemical warfare. During World War I, he played a major role in the development of poisonous gases used for trench warfare. Regarding his role in these developments, Haber said, “During peace time a scientist belongs to the World, but during war time he belongs to his country.”1 Haber defended the use of gas warfare against accusations that it was inhumane, saying that death was death, by whatever means it was inflicted. He stands as an example of the ethical dilemmas that face scientists in times of war and the double-edged nature of the sword of science. Like Haber, the products made from ammonia can be multifaceted. In addition to their value for agriculture, nitrogen compounds can also be used to achieve destructive ends. Ammonium nitrate has also been used in explosives, including improvised explosive devices. Ammonium nitrate was one of the components of the bomb used in the attack on the Alfred P. Murrah Federal Building in downtown Oklahoma City on April 19, 1995. It has long been known that nitrogen and hydrogen react to form ammonia. However, it became possible to manufacture ammonia in useful quantities by the reaction of nitrogen and hydrogen only in the early 20th century after the factors that influence its equilibrium were understood. To be practical, an industrial process must give a large yield of product relatively quickly. One way to increase the yield of ammonia is to increase the pressure on the system in which N2, H2, and NH3 are at equilibrium or are coming to equilibrium. The formation of additional amounts of ammonia reduces the total pressure exerted by the system and somewhat reduces the stress of the increased pressure. Although increasing the pressure of a mixture of N2, H2, and NH3 will increase the yield of ammonia, at low temperatures, the rate of formation of ammonia is slow. At room temperature, for example, the reaction is so slow that if we prepared a mixture of N2 and H2, no detectable amount of ammonia would form during our lifetime. The formation of ammonia from hydrogen and nitrogen is an exothermic process: Thus, increasing the temperature to increase the rate lowers the yield. If we lower the temperature to shift the equilibrium to favor the formation of more ammonia, equilibrium is reached more slowly because of the large decrease of reaction rate with decreasing temperature. Part of the rate of formation lost by operating at lower temperatures can be recovered by using a catalyst. The net effect of the catalyst on the reaction is to cause equilibrium to be reached more rapidly. In the commercial production of ammonia, conditions of about 500 °C, 150–900 atm, and the presence of a catalyst are used to give the best compromise among rate, yield, and the cost of the equipment necessary to produce and contain high-pressure gases at high temperatures ((Figure)). Among the factors affecting chemical reaction rates discussed earlier in this chapter was the presence of a catalyst, a substance that can increase the reaction rate without being consumed in the reaction. The concepts introduced in the previous section on reaction mechanisms provide the basis for understanding how catalysts are able to accomplish this very important function. (Figure) shows reaction diagrams for a chemical process in the absence and presence of a catalyst. Inspection of the diagrams reveals several traits of these reactions. Consistent with the fact that the two diagrams represent the same overall reaction, both curves begin and end at the same energies (in this case, because products are more energetic than reactants, the reaction is endothermic). The reaction mechanisms, however, are clearly different. The uncatalyzed reaction proceeds via a one-step mechanism (one transition state observed), whereas the catalyzed reaction follows a two-step mechanism (two transition states observed) with a notably lesser activation energy. This difference illustrates the means by which a catalyst functions to accelerate reactions, namely, by providing an alternative reaction mechanism with a lower activation energy. Although the catalyzed reaction mechanism for a reaction needn’t necessarily involve a different number of steps than the uncatalyzed mechanism, it must provide a reaction path whose rate determining step is faster (lower Ea). Reaction Diagrams for Catalyzed Reactions The two reaction diagrams here represent the same reaction: one without a catalyst and one with a catalyst. Estimate the activation energy for each process, and identify which one involves a catalyst. Solution Activation energies are calculated by subtracting the reactant energy from the transition state energy. The catalyzed reaction is the one with lesser activation energy, in this case represented by diagram (b). Check Your Learning Reaction diagrams for a chemical process with and without a catalyst are shown below. Both reactions involve a two-step mechanism with a rate-determining first step. Compute activation energies for the first step of each mechanism, and identify which corresponds to the catalyzed reaction. How do the second steps of these two mechanisms compare? For the first step, Ea = 80 kJ for (a) and 70 kJ for (b), so diagram (b) depicts the catalyzed reaction. Activation energies for the second steps of both mechanisms are the same, 20 kJ. Homogeneous Catalysts A homogeneous catalyst is present in the same phase as the reactants. It interacts with a reactant to form an intermediate substance, which then decomposes or reacts with another reactant in one or more steps to regenerate the original catalyst and form product. As an important illustration of homogeneous catalysis, consider the earth’s ozone layer. Ozone in the upper atmosphere, which protects the earth from ultraviolet radiation, is formed when oxygen molecules absorb ultraviolet light and undergo the reaction: Ozone is a relatively unstable molecule that decomposes to yield diatomic oxygen by the reverse of this equation. This decomposition reaction is consistent with the following two-step mechanism: A number of substances can catalyze the decomposition of ozone. For example, the nitric oxide -catalyzed decomposition of ozone is believed to occur via the following three-step mechanism: As required, the overall reaction is the same for both the two-step uncatalyzed mechanism and the three-step NO-catalyzed mechanism: Notice that NO is a reactant in the first step of the mechanism and a product in the last step. This is another characteristic trait of a catalyst: Though it participates in the chemical reaction, it is not consumed by the reaction. The 1995 Nobel Prize in Chemistry was shared by Paul J. Crutzen, Mario J. Molina ((Figure)), and F. Sherwood Rowland “for their work in atmospheric chemistry, particularly concerning the formation and decomposition of ozone.”2 Molina, a Mexican citizen, carried out the majority of his work at the Massachusetts Institute of Technology (MIT). In 1974, Molina and Rowland published a paper in the journal Nature detailing the threat of chlorofluorocarbon gases to the stability of the ozone layer in earth’s upper atmosphere. The ozone layer protects earth from solar radiation by absorbing ultraviolet light. As chemical reactions deplete the amount of ozone in the upper atmosphere, a measurable “hole” forms above Antarctica, and an increase in the amount of solar ultraviolet radiation— strongly linked to the prevalence of skin cancers—reaches earth’s surface. The work of Molina and Rowland was instrumental in the adoption of the Montreal Protocol, an international treaty signed in 1987 that successfully began phasing out production of chemicals linked to ozone destruction. Molina and Rowland demonstrated that chlorine atoms from human-made chemicals can catalyze ozone destruction in a process similar to that by which NO accelerates the depletion of ozone. Chlorine atoms are generated when chlorocarbons or chlorofluorocarbons—once widely used as refrigerants and propellants—are photochemically decomposed by ultraviolet light or react with hydroxyl radicals. A sample mechanism is shown here using methyl chloride: Chlorine radicals break down ozone and are regenerated by the following catalytic cycle: A single monatomic chlorine can break down thousands of ozone molecules. Luckily, the majority of atmospheric chlorine exists as the catalytically inactive forms Cl2 and ClONO2. Since receiving his portion of the Nobel Prize, Molina has continued his work in atmospheric chemistry at MIT. Enzymes in the human body act as catalysts for important chemical reactions in cellular metabolism. As such, a deficiency of a particular enzyme can translate to a life-threatening disease. G6PD (glucose-6-phosphate dehydrogenase) deficiency, a genetic condition that results in a shortage of the enzyme glucose-6-phosphate dehydrogenase, is the most common enzyme deficiency in humans. This enzyme, shown in (Figure), is the rate-limiting enzyme for the metabolic pathway that supplies NADPH to cells ((Figure)). A disruption in this pathway can lead to reduced glutathione in red blood cells; once all glutathione is consumed, enzymes and other proteins such as hemoglobin are susceptible to damage. For example, hemoglobin can be metabolized to bilirubin, which leads to jaundice, a condition that can become severe. People who suffer from G6PD deficiency must avoid certain foods and medicines containing chemicals that can trigger damage their glutathione-deficient red blood cells. Heterogeneous Catalysts A heterogeneous catalyst is a catalyst that is present in a different phase (usually a solid) than the reactants. Such catalysts generally function by furnishing an active surface upon which a reaction can occur. Gas and liquid phase reactions catalyzed by heterogeneous catalysts occur on the surface of the catalyst rather than within the gas or liquid phase. Heterogeneous catalysis typically involves the following processes: - Adsorption of the reactant(s) onto the surface of the catalyst - Activation of the adsorbed reactant(s) - Reaction of the adsorbed reactant(s) - Desorption of product(s) from the surface of the catalyst (Figure) illustrates the steps of a mechanism for the reaction of compounds containing a carbon–carbon double bond with hydrogen on a nickel catalyst. Nickel is the catalyst used in the hydrogenation of polyunsaturated fats and oils (which contain several carbon–carbon double bonds) to produce saturated fats and oils (which contain only carbon–carbon single bonds). Many important chemical products are prepared via industrial processes that use heterogeneous catalysts, including ammonia, nitric acid, sulfuric acid, and methanol. Heterogeneous catalysts are also used in the catalytic converters found on most gasoline-powered automobiles ((Figure)). Scientists developed catalytic converters to reduce the amount of toxic emissions produced by burning gasoline in internal combustion engines. By utilizing a carefully selected blend of catalytically active metals, it is possible to effect complete combustion of all carbon-containing compounds to carbon dioxide while also reducing the output of nitrogen oxides. This is particularly impressive when we consider that one step involves adding more oxygen to the molecule and the other involves removing the oxygen ((Figure)). Most modern, three-way catalytic converters possess a surface impregnated with a platinum-rhodium catalyst, which catalyzes the conversion of nitric oxide into dinitrogen and oxygen as well as the conversion of carbon monoxide and hydrocarbons such as octane into carbon dioxide and water vapor: In order to be as efficient as possible, most catalytic converters are preheated by an electric heater. This ensures that the metals in the catalyst are fully active even before the automobile exhaust is hot enough to maintain appropriate reaction temperatures. The University of California at Davis’ “ChemWiki” provides a thorough explanation of how catalytic converters work. The study of enzymes is an important interconnection between biology and chemistry. Enzymes are usually proteins (polypeptides) that help to control the rate of chemical reactions between biologically important compounds, particularly those that are involved in cellular metabolism. Different classes of enzymes perform a variety of functions, as shown in (Figure). \| Classes of Enzymes and Their Functions \| \| \|---\|---\| \| Class \| Function \| \| oxidoreductases \| redox reactions \| \| transferases \| transfer of functional groups \| \| hydrolases \| hydrolysis reactions \| \| lyases \| group elimination to form double bonds \| \| isomerases \| isomerization \| \| ligases \| bond formation with ATP hydrolysis \| Enzyme molecules possess an active site, a part of the molecule with a shape that allows it to bond to a specific substrate (a reactant molecule), forming an enzyme-substrate complex as a reaction intermediate. There are two models that attempt to explain how this active site works. The most simplistic model is referred to as the lock-and-key hypothesis, which suggests that the molecular shapes of the active site and substrate are complementary, fitting together like a key in a lock. The induced fit hypothesis, on the other hand, suggests that the enzyme molecule is flexible and changes shape to accommodate a bond with the substrate. This is not to suggest that an enzyme’s active site is completely malleable, however. Both the lock-and-key model and the induced fit model account for the fact that enzymes can only bind with specific substrates, since in general a particular enzyme only catalyzes a particular reaction ((Figure)). The Royal Society of Chemistry provides an excellent introduction to enzymes for students and teachers. The connection between the rate of a reaction and its equilibrium constant is one we can easily determine with just a bit of algebraic substitution. For a reaction where substance A forms B (and the reverse) The rate of the forward reaction is And the rate of the reverse reaction is Once equilibrium is established, the rates of the forward and reverse reactions are equal: Rearranging a bit, we get Also recall that the equilibrium constant is simply the ratio of product to reactant concentration at equilibrium: So the equilibrium constant turns out to be the ratio of the forward to the reverse rate constants. This relationship also helps cement our understanding of the nature of a catalyst. That is, a catalyst does not change the fundamental equilibrium (or the underlying thermodynamics) of a reaction. Rather, what it does is alter the rate constant for the reaction – that is, both rate constants, forward and reverse, equally. In doing so, catalysts usually speed up the rate at which reactions attain equilibrium (though they can be used to slow down the rate of reaction as well!). Key Concepts and Summary Catalysts affect the rate of a chemical reaction by altering its mechanism to provide a lower activation energy, but they do not affect equilibrium. Catalysts can be homogenous (in the same phase as the reactants) or heterogeneous (a different phase than the reactants). Chemistry End of Chapter Exercises Account for the increase in reaction rate brought about by a catalyst. The general mode of action for a catalyst is to provide a mechanism by which the reactants can unite more readily by taking a path with a lower reaction energy. The rates of both the forward and the reverse reactions are increased, leading to a faster achievement of equilibrium. Compare the functions of homogeneous and heterogeneous catalysts. Consider this scenario and answer the following questions: Chlorine atoms resulting from decomposition of chlorofluoromethanes, such as CCl2F2, catalyze the decomposition of ozone in the atmosphere. One simplified mechanism for the decomposition is: $\begin{array}{}\\ \\ {\text{O}}_{3}\stackrel{\phantom{\rule{0.2em}{0ex}}\text{sunlight}\phantom{\rule{0.2em}{0ex}}}{\to }{\text{O}}_{2}+\text{O}\\ {\text{O}}_{3}+\text{Cl}\phantom{\rule{0.2em}{0ex}}⟶\phantom{\rule{0.2em}{0ex}}{\text{O}}_{2}+\text{ClO}\\ \text{ClO}+\text{O}\phantom{\rule{0.2em}{0ex}}⟶\phantom{\rule{0.2em}{0ex}}\text{Cl}+{\text{O}}_{2}\end{array}$ (a) Explain why chlorine atoms are catalysts in the gas-phase transformation: $2{\text{O}}_{3}\phantom{\rule{0.2em}{0ex}}⟶\phantom{\rule{0.2em}{0ex}}3{\text{O}}_{2}$ (b) Nitric oxide is also involved in the decomposition of ozone by the mechanism: $\begin{array}{}\\ {\text{O}}_{3}\stackrel{\phantom{\rule{0.2em}{0ex}}\text{sunlight}\phantom{\rule{0.2em}{0ex}}}{\to }{\text{O}}_{2}+\text{O}\\ {\text{O}}_{3}+\text{NO}\phantom{\rule{0.2em}{0ex}}⟶\phantom{\rule{0.2em}{0ex}}{\text{NO}}_{2}+{\text{O}}_{2}\\ {\text{NO}}_{2}+\text{O}\phantom{\rule{0.2em}{0ex}}⟶\phantom{\rule{0.2em}{0ex}}\text{NO}+{\text{O}}_{2}\end{array}$ Is NO a catalyst for the decomposition? Explain your answer. (a) Chlorine atoms are a catalyst because they react in the second step but are regenerated in the third step. Thus, they are not used up, which is a characteristic of catalysts. (b) NO is a catalyst for the same reason as in part (a). Water gas is a 1:1 mixture of carbon monoxide and hydrogen gas and is called water gas because it is formed from steam and hot carbon in the following reaction: ${\text{H}}_{2}\text{O}\left(g\right)+\text{C}\left(s\right)⇌{\text{H}}_{2}\left(g\right)+\text{CO}\left(g\right).$ Methanol, a liquid fuel that could possibly replace gasoline, can be prepared from water gas and hydrogen at high temperature and pressure in the presence of a suitable catalyst. What will happen to the concentrations of H2, CO, and CH3OH at equilibrium if more catalyst is added? no changes. Nitrogen and oxygen react at high temperatures. What will happen to the concentrations of N2, O2, and NO at equilibrium if a catalyst is added? For each of the following pairs of reaction diagrams, identify which of the pair is catalyzed: (a) (b) For each of the following pairs of reaction diagrams, identify which of the pairs is catalyzed: (a) (b) The lowering of the transition state energy indicates the effect of a catalyst. (a) B; (b) B For each of the following reaction diagrams, estimate the activation energy (Ea) of the reaction: (a) (b) For each of the following reaction diagrams, estimate the activation energy (Ea) of the reaction: (a) (b) The energy needed to go from the initial state to the transition state is (a) 10 kJ; (b) 10 kJ Assuming the diagrams in (Figure) represent different mechanisms for the same reaction, which of the reactions has the faster rate? Consider the similarities and differences in the two reaction diagrams shown in (Figure). Do these diagrams represent two different overall reactions, or do they represent the same overall reaction taking place by two different mechanisms? Explain your answer. Both diagrams describe two-step, exothermic reactions, but with different changes in enthalpy, suggesting the diagrams depict two different overall reactions. Footnotes - 1Herrlich, P. “The Responsibility of the Scientist: What Can History Teach Us About How Scientists Should Handle Research That Has the Potential to Create Harm?” EMBO Reports 14 (2013): 759–764. - 2“The Nobel Prize in Chemistry 1995,” Nobel Prize.org, accessed February 18, 2015, http://www.nobelprize.org/nobel_prizes/chemistry/laureates/1995/. Glossary - heterogeneous catalyst - catalyst present in a different phase from the reactants, furnishing a surface at which a reaction can occur - homogeneous catalyst - catalyst present in the same phase as the reactants	4,431	common-pile/pressbooks_filtered	https://pressbooks.nscc.ca/chemistryatoms/chapter/catalysis/	pressbooks	pressbooks-0000.json.gz:72483	https://pressbooks.nscc.ca/chemistryatoms/chapter/catalysis/
SLfzYGdYcDYxkzpm	Science Technology and Society a Student Led Exploration	Technology 133 Language Learning & Technology Language learning has experienced a profound transformation with the integration of technology, redefining traditional approaches and offering learners innovative tools, interactive platforms, and personalized resources. In this evolving landscape, technology plays a pivotal role in enhancing engagement, proficiency, and cultural awareness among language learners. Modern language learning is characterized by the use of technology-driven tools that revolutionize the acquisition and practice of language skills. For instance, language learning apps like Duolingo, Rosetta Stone, and Babbel provide interactive lessons, virtual reality offers immersive language experiences, and speech recognition software aids in pronunciation practice. These innovative tools contribute to a more accessible, interactive, and tailored learning experience, ultimately improving language acquisition. Interactive language learning platforms create opportunities for real-time communication and collaboration. Language exchange websites such as Tandem and HelloTalk connect learners globally for language exchange, while online language communities foster discussion and practice. The benefits of these interactive platforms extend beyond language proficiency, promoting cultural exchange and providing exposure to diverse linguistic contexts. Personalized resources cater to individual learning styles, adapting content to meet specific needs. Adaptive learning systems like Memrise adjust content based on individual progress, and customized lesson plans allow learners to focus on specific language aspects. This personalization empowers learners, addressing their unique strengths and weaknesses, and contributes to a more efficient language learning. Technology enhances engagement through various means, such as gamification, multimedia content, and interactive exercises. Gamification elements in language apps make learning enjoyable, while multimedia content, including audio, video, and interactive exercises, diversifies learning materials. Increased engagement leads to greater motivation, active participation, and improved retention, ultimately contributing to successful language learning outcomes. Technology aids in improving language proficiency by facilitating consistent and interactive language practice. Regular practice, coupled with instant feedback from technology, accelerates the learning process by reinforcing correct usage and identifying areas for improvement. Language learning platforms and assessment tools further contribute to proficiency improvement, offering authentic content and personalized feedback. Technology plays a crucial role in enhancing cultural awareness by exposing learners to multimedia content, virtual experiences, and interactive platforms. Videos, podcasts, and virtual cultural experiences provide insights into the cultural context of language usage. This increased cultural awareness enriches language skills and promotes cross-cultural understanding, fostering more culturally competent language learners. In conclusion, the transformative impact of technology on language learning is evident across innovative tools, interactive platforms, personalized resources, enhanced engagement, improved proficiency, and increased cultural awareness. Affirming the thesis statement, technology continues to evolve, promising even more advancements in language education, ensuring learners have access to increasingly effective and personalized language learning experiences. I credit this this piece of writing to AI & ChatGPT (August 25, 2023 Friday). Endless globalization. CE Noticias Financieras English. https://advance-lexis-com.libproxy.clemson.edu/api/document?collection=news&id=urn:contentItem:691H-PRW1-DYY9-01PV-00000-00&context=1516831. (August 25, 2023 Friday). New Findings from University of Hong Kong in the Area of Technology Reported (Individual Interest, Self-regulation, and Self-directed Language Learning With Technology Beyond the Classroom). Daily Hong Kong Report. https://advance-lexis-com.libproxy.clemson.edu/api/document?collection=news&id=urn:contentItem:691C-J091-JBSP-12J5-00000-00&context=1516831. razak.bawa. (June 14, 2023 Wednesday). Unlocking the Power of AI: Five ways technology enhances language learning. The Herald (Ghana). https://advance-lexis-com.libproxy.clemson.edu/api/document?collection=news&id=urn:contentItem:68G0-FVN1-JDJN-650T-00000-00&context=1516831. Shadiev, R., & Wang, X. (2022, June 13). A review of research on technology-supported language learning and 21st Century skills. Frontiers. https://www.frontiersin.org/articles/10.3389/fpsyg.2022.897689/full The role of technology in language learning. ACTFL. (n.d.). https://www.actfl.org/news/the-role-of-technology-in-language-learning#:~:text=Through%20the%20purposeful%20use%20of,speakers%20of%20the%20target%20language The Sentinel Assam. (2023, April 14). Technology impacts language learning – sentinelassam. The Sentinel Assam. https://www.sentinelassam.com/life/technology-impacts-language-learning-645670	721	common-pile/pressbooks_filtered	https://opentextbooks.clemson.edu/sciencetechnologyandsociety/chapter/language-learning-technology/	pressbooks	pressbooks-0000.json.gz:69915	https://opentextbooks.clemson.edu/sciencetechnologyandsociety/chapter/language-learning-technology/
vEqfaD75pdKJefT4	1.4.9: Sets of Different Sizes, and Cantor’s Theorem	1.4.9: Sets of Different Sizes, and Cantor’s Theorem We have offered a precise statement of the idea that two sets have the same size. We can also offer a precise statement of the idea that one set is smaller than another. Our definition of “is smaller than (or equinumerous)” will require, instead of a bijection between the sets, an injection from the first set to the second. If such a function exists, the size of the first set is less than or equal to the size of the second. Intuitively, an injection from one set to another guarantees that the range of the function has at least as many elements as the domain, since no two elements of the domain map to the same element of the range. $A$ is no larger than $B$ , written $\cardle{A}{B}$ , iff there is an injection $f \colon A \to B$ . It is clear that this is a reflexive and transitive relation, but that it is not symmetric (this is left as an exercise). We can also introduce a notion, which states that one set is (strictly) smaller than another. $A$ is smaller than $B$ , written $\cardless{A}{B}$ , iff there is an injection $f\colon A \to B$ but no bijection $g\colon A \to B$ , i.e., $\cardle{A}{B}$ and $\cardneq{A}{B}$ . It is clear that this relation is anti-reflexive and transitive. (This is left as an exercise.) Using this notation, we can say that a set $A$ is enumerable iff $\cardle{A}{\Nat}$ , and that $A$ is non-enumerable iff $\cardless{\Nat}{A}$ . This allows us to restate Theorem 4.6.2 as the observation that $\cardless{\Nat}{\Pow{\Nat}}$ . In fact, Cantor (1892) proved that this last point is perfectly general : $\cardless{A}{\Pow{A}}$ , for any set $A$ . Proof. The map $f(x) = \{x\}$ is an injection $f \colon A \to \Pow{A}$ , since if $x \neq y$ , then also $\{x\} \neq \{y\}$ by extensionality, and so $f(x) \neq f(y)$ . So we have that $\cardle{A}{\Pow{A}}$ . We show that there cannot be a surjective function $g\colon A \to \Pow{A}$ , let alone a bijective one, and hence that $\cardneq{A}{\Pow{A}}$ . For suppose that $g\colon A \to \Pow{A}$ . Since $g$ is total, every $x \in A$ is mapped to a subset $g(x) \subseteq A$ . We show that $g$ cannot be surjective. To do this, we define a subset $\overline{A} \subseteq A$ which by definition cannot be in the range of $g$ . Let \[\overline{A} = \Setabs{x \in A}{x \notin g(x)}.\nonumber\] Since $g(x)$ is defined for all $x \in A$ , $\overline{A}$ is clearly a well-defined subset of $A$ . But, it cannot be in the range of $g$ . Let $x \in A$ be arbitrary, we show that $\overline{A} \neq g(x)$ . If $x \in g(x)$ , then it does not satisfy $x \notin g(x)$ , and so by the definition of $\overline{A}$ , we have $x \notin \overline{A}$ . If $x \in \overline{A}$ , it must satisfy the defining property of $\overline{A}$ , i.e., $x \in A$ and $x \notin g(x)$ . Since $x$ was arbitrary, this shows that for each $x \in \overline{A}$ , $x \in g(x)$ iff $x \notin \overline{A}$ , and so $g(x) \neq \overline{A}$ . In other words, $\overline{A}$ cannot be in the range of $g$ , contradicting the assumption that $g$ is surjective. ◻ It’s instructive to compare the proof of Theorem $\PageIndex{1}$ to that of Theorem 4.6.2 . There we showed that for any list $Z_1$ , $Z_2$ , …, of subsets of $\PosInt$ one can construct a set $\overline{Z}$ of numbers guaranteed not to be on the list. It was guaranteed not to be on the list because, for every $n \in \PosInt$ , $n \in Z_n$ iff $n \notin \overline{Z}$ . This way, there is always some number that is an element of one of $Z_n$ or $\overline{Z}$ but not the other. We follow the same idea here, except the indices $n$ are now elements of $A$ instead of $\PosInt$ . The set $\overline{B}$ is defined so that it is different from $g(x)$ for each $x \in A$ , because $x \in g(x)$ iff $x \notin \overline{B}$ . Again, there is always an element of $A$ which is an element of one of $g(x)$ and $\overline{B}$ but not the other. And just as $\overline{Z}$ therefore cannot be on the list $Z_1$ , $Z_2$ , …, $\overline{B}$ cannot be in the range of $g$ . The proof is also worth comparing with the proof of Russell’s Paradox, Theorem 1.6.1 . Indeed, Cantor’s Theorem was the inspiration for Russell’s own paradox. Show that there cannot be an injection $g\colon \Pow{A} \to A$ , for any set $A$ . Hint: Suppose $g\colon \Pow{A} \to A$ is injective. Consider $D = \Setabs{g(B)}{B \subseteq A \text{ and } g(B) \notin B}$ . Let $x = g(D)$ . Use the fact that $g$ is injective to derive a contradiction.	1,063	common-pile/libretexts_filtered	https://human.libretexts.org/Bookshelves/Philosophy/Sets_Logic_Computation_(Zach)/01%3A_I-_Sets_Relations_Functions/1.04%3A_The_Size_of_Sets/1.4.09%3A_Sets_of_Different_Sizes_and_Cantors_Theorem	libretexts	libretexts-0000.json.gz:15568	https://human.libretexts.org/Bookshelves/Philosophy/Sets_Logic_Computation_(Zach)/01%3A_I-_Sets_Relations_Functions/1.04%3A_The_Size_of_Sets/1.4.09%3A_Sets_of_Different_Sizes_and_Cantors_Theorem
n2CfJ-0PdR8Nc4-Q	4.8: Learning Activities	4.8: Learning Activities Exercises (Answers to the exercises are located in the Answer Key at the back of the book). Case Study #1 Autumn, age 32, has a history of Diabetes Mellitus Type II and has been admitted to the hospital with a left lower leg wound that developed cellulitis. She has been receiving antibiotic therapy in the hospital for the past two days through a right upper arm PICC line and is now ready for discharge. When at home, she will continue to receive cefazolin 500 mg IV every 8 hours for the next 14 days. 1. What will you provide for patient education for Autumn regarding her PICC line? 2. What are the maintenance care priorities for care of the PICC line? 3. Are there any specific concerns related to Autumn’s need for a PICC line that should be monitored or addressed? 4. What is the purpose of the PICC line? 5. How often should a PICC line be assessed? 6. How does the dressing get changed for a PICC line? 7. What makes a PICC line different from a peripheral IV and from an implanted port? An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingadvancedskills/?p=458#h5p-10 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingadvancedskills/?p=458#h5p-11 An interactive H5P element has been excluded from this version of the text. You can view it online here: https://wtcs.pressbooks.pub/nursingadvancedskills/?p=458#h5p-12	323	common-pile/libretexts_filtered	https://med.libretexts.org/Bookshelves/Nursing/Nursing_Advanced_Skills_(OpenRN)/04%3A_Manage_Central_Lines/4.08%3A_Learning_Activities	libretexts	libretexts-0000.json.gz:26539	https://med.libretexts.org/Bookshelves/Nursing/Nursing_Advanced_Skills_(OpenRN)/04%3A_Manage_Central_Lines/4.08%3A_Learning_Activities
X_eKcBOT-eiGJhil	23.9: Review Questions	23.9: Review Questions - - Last updated - Save as PDF 1. The nurse is assessing a client who lives in an area described as a food desert. The nurse identifies that the client is therefore at risk for which disorder? - Obesity - Parkinson’s disease - Multiple sclerosis - Chronic obstructive pulmonary disease 2. Which is an example of a nurse practicing culturally congruent care? - Using evidence-based nursing practice - Practicing nursing according to the nurse’s beliefs - Discouraging the use of a traditional healer - Using standardized care plans 3. Which term describes the actions of a nurse who orders a kosher diet for a Jewish client based on previous experience with other Jewish clients? - Stereotyping - Bias - Othering - Ethnocentrism 4. Which concept does the nurse identify as an organizational barrier to culturally competent health care in a community? - Not enough primary care providers in a community - A lack of medical interpreters - Absence of health care insurance - An inability to afford health care 5. Which construct do nurses exhibit when they engage in self-reflection about their own cultural beliefs and biases? - Cultural skill - Cultural desire - Cultural awareness - Cultural knowledge 6. Which actions by the nurse demonstrate that the nurse values cultural diversity? - The nurse discusses cultural diversity with people from their own culture. - The nurse compares other cultures to the nurse’s culture. - The nurse treats everyone from the same culture in a similar manner. - The nurse volunteers at a free immigrant health clinic. 7. Which action should the nurse take when a client of a different culture than the nurse stares out the window while the nurse is providing preoperative instruction? - Stare out the window with the client. - Move around the bed to stand in front of the client. - Observe how the client uses eye contact. - Stop the instruction and return later. 8. Which action should the nurse take when teaching a client with a low health literacy level? - Use the correct medical terminology. - Speak in a loud voice. - Choose terms that the client uses. - Use verbal instruction only. 9. Which is the best action for the nurse to take when communicating with a client who speaks a language the nurse does not understand? - Arrange for a medical interpreter. - Ask a family member to translate. - Ask a clerical staff member who speaks the language to translate. - Use a smartphone app to translate. 10. Which action should the nurse take when developing written educational materials for a specific population? - Use appropriate medical terms. - Ask community members to review the materials. - Write at a high school reading level.	596	common-pile/libretexts_filtered	https://med.libretexts.org/Bookshelves/Nursing/Population_Health_for_Nurses_(OpenStax)/23%3A_Culturally_and_Linguistically_Responsive_Nursing_Care/23.09%3A_Review_Questions	libretexts	libretexts-0000.json.gz:1903	https://med.libretexts.org/Bookshelves/Nursing/Population_Health_for_Nurses_(OpenStax)/23%3A_Culturally_and_Linguistically_Responsive_Nursing_Care/23.09%3A_Review_Questions
pB37yTzY8xSTLJMZ	Appletons' school physics : embracing the results of the most recent researches in the several departments of natural philosophy / by John D. Quackenbos ... [et al.]	PREFACE. THE present volume is intended to meet an existing demand for a thoroughly modern text-book on Natural Philosophy, which shall reflect the most advanced and practical laboratory and pedagogical methods, and at the same time be adapted, in style and matter, for use in the higher grades of our grammar-schools, our high-schools, and our academies. In the belief that special investigators and teachers are distinctively qualified for the purpose, the editor has assigned the different sections of the book to educators of recognized eminence and skill, governing his selection in each case by the peculiar qualifications of the author. The reputation of the several contributors, and the standing of the great scientific schools which they represent, must secure for this work a consideration accorded to few American schooltexts. The sections on motion, energy, force, the properties and constitution of matter, solids, liquids, gases, and mechanics proper, were prepared by Professor Silas W. Holman, of the Massachusetts Institute of Technology ; those on heat, light, f rictional and voltaic electricity, by Francis E. Nipher, Professor of Physics in Washington University, St. Louis. Professor Alfred M. Mayer, of the Stevens Institute of Technology, Hoboken, N. J., furnished the chapter on sound ; and Francis B. Crocker, E. M., Instructor in Electrical Engineering, School of Mines, Columbia College, the sections relating to magnetism and the practical applications of electricity. Numerous friends of the book have aided the editor with valuable suggestions and criticisms ; special acknowledgment is due to Professors Rood, Trowbridge, and "Rees, of Columbia College, and Professor George F. Swain, of the Massachusetts Institute of Technology. The attention of teachers is asked to the following specific features : The thorough and original treatment of motion, energy, force, and work. In the chapters on dynamics, the author has presented a modern and appliable conception of the nature, transformation, and conservation of energy, as well as of the relation existing between energy and force. These subjects are treated with the greatest simplicity, The book is adapted to students of fourteen years and upward, but by the occasional omission of an advanced paragraph, an algebraic expression, or an exceptionally difficult principle, the text becomes perfectly comprehensible to the most juvenile learners. Thus it is essentially fitted to pupils of different degrees of maturity. The easier principles may form the basis of a first year's course ; while, in the second year, the student will find in the complete text additional matters which increased age and extended experience now enable him to grasp and appreciate. It has been the aim of the authors of this volume not to teach results merely, but to show how these results have been reached as well as what practical use is made of them, and thus to inspire the learner with enthusiasm in his work of questioning Nature. Precedence is everywhere given to the practical. The steam-engine, the electric motor, the telephone, and the telegraph, even the simplest tools, are shown to be machines or devices by which energy of some form is made to do work useful to man. The experiments, especially those described in the chapters on dynamics, etc., are largely intended as illustrations, and not as proofs ; hence the pupil is not led to draw extended inferences from insufficient evidence — a habit antagonistic to proper and symmetrical mental development. Further, the significance of the algebraic formulae is immediately impressed upon the learner by solved numerical examples. This feature is of special importance in the earlier discussions, where the abstract or general statements are rendered much more intelligible because accompanied with concrete forms. Instructive diagrams and illustrations have been introduced wherever it was thought they would relieve the text ; suggestive questions, not intended to supersede minute examination by the teacher, but rather to exercise the reasoning faculties of the pupil, are inserted at such intervals as mark convenient and logical divisions into lessons ; problems are appended to the several sections, to test the student's understanding of the principles therein explained; and applications of these principles in every-day experience render them delightful to learn and easy to remember. The illustrations not only reproduce the more complicated apparatus usually found in the school laboratory, but also elucidate the descriptions of simple experiments that can be successfully attempted by young people with home-made appliances. At the beginning of each principal section is pictured a suggestive group of such apparatus as will be found necessary to the performance of the experiments described in the chapter following ; and, throughout the book, minute instructions are given for the cheap manufacture of essential pieces of apparatus. The publishers feel assured that the many valuable features of this new School Physics must recommend it to teachers as a singularly practical and authoritative text-book on the subjects of which it treats. PRELIMINARY STATEMENTS AND DEFINITIONS. The Fundamental Things about which we have to learn in Physics are Matter and its Motion — matter, out of which everything is built up ; motion, which gives to matter the possibility of form, structure, phenomena, and laws, and which is everywhere and unceasing. Matter in motion possesses Energy — that which not only does all the work of the universe, but which holds every particle to its neighbor and yet keeps it apart from that neighbor. Physical Science deals only with the phenomena and laws of matter, and of matter in motion. It does not attempt to determine whence matter and its motion came, what matter is, or how it acquired motion. It does not deny that other things than matter in motion are essential to the universe. We are everywhere surrounded by objects which form a part of what we call the physical universe. In studying them we proceed upon the suppositions or beliefs — sift the truth from the error in our interpretation of these indications. Phenomena. — As we examine and consider the objects about us, we perceive that they differ as to size, shape, color, hardness, position, and many other characteristics or qualities. We also perceive that they are concerned in certain events or occurrences which are going on naturally, Or can be made to take place. Thus, we observe that objects when dropped fall to the ground, that water on a sloping surface runs downward, that an object held up in the sunshine casts a shadow, that the sun appears to rise in the east and set in the west. Science. — But a mere examination and cataloguing of objects and phenomena would never give us a science. Science involves a study of the relations between different objects and between phenomena. These relations must be analyzed and expressed in general statements, which are called Laws. The whole body of truth thus gained, namely, the knowledge of material objects, phenomena, and relations or laws, constitutes the science called Physics, or Natural Philosophy. Law. — Let us look a little more closely at what is meant by physical laws. If almost any object whatever be held up from the earth's surface and then be released, it will fall to the ground. From our own experience and that of others in the past, we know that every object tested in this way has fallen except where for some well-understood cause it was prevented from so doing, as, for instance, a balloon by the buoyancy of the air or a feather by the resistance of the air. We may, therefore, say that every object tested has shown a tendency to fall toward the earth. PHYSICAL LAW. 3 must it be changed to become one ? Simply by being made general — that is, it must be expressed so as to apply to all bodies. If, then, we say every body near the earth possesses a tendency to fall, that is, has weight, we shall have a statement of the class which we call laws. This statement includes every body near the earth, whether it has been tested or not. Now, how do we know that this law is true ? "We do not know that it is true in the same sense that we know the truth of the first statement. We can not even have the same certainty that a given object which has weight to-day will have weight to-morrow. How, then, can we have any confidence in general statements or predictions based upon past experience H And if these laws are an essential part ol science, how much reliance is to be placed upon them ? There certainly is such a thing as too great confidence in science, and there is a wide difference between the degrees of confidence to be given to different scientific laws. These laws are being continually developed and corrected, and the measure of confidence to which they are entitled depends on the thoroughness with which the underlying facts were examined, and in the exactness with which subsequently observed facts and phenomena have been found to coincide with the law. The chief reason why we are disposed to put confidence in laws and predictions is our belief in the proposition that " the same causes will always produce the same effects." This is a generalized statement of our own and all past experience, viz., that the same causes have always produced the same effects, and our belief in it is measured by the breadth of experience upon which it rests. It must be remembered that laws do not " govern " events in the sense of causing them. A law is merely the general ized statement of what has been observed to occur. Cause and Effect. — What do these terms mean ? Push a book lying on the table. It moves. Try the experiment under a variety of conditions as to time, place, temperature, and so on. You will find that the push, unless neutralized in some obvious way, always produces the motion, and that the motion does not occur without a push. You conclude, then, that it appears not to be simply a matter of 4 PHYSICS, OR NATURAL PHILOSOPHY. chance that the push and the motion occur at the same time, but that they necessarily occur together, and that the motion appears to result from the push. The push is then said to be the cause of the motion, and the motion the effect of the push. We should feel a considerable degree of confidence, then, in making the generalized statement that the push, unless neutralized, always will produce the motion ; but we should not pretend to say that this statement is absolutely true, for, besides the liability to some imperfection in our observations, we are not certain of the truth of the proposition, " the same causes always produce the same effects " ; and this is an essential part of the process by which we have arrived at the general statement. In the application of this proposition, we must bear in mind that if the cause be not precisely the same (except with respect to time), the effect will not be precisely the same ; it may be extraordinarily different. For instance, a burnt-out match may be repeatedly thrust into gunpowder, with always the same effect of merely pushing aside the grains ; but, if the match differs only by being slightly hotter on some occasion, the effect may be strikingly changed. Chance. — A multitude of events which take place around us occur at times or places or in ways which, so far as we can see, are without any order or any apparent law or reason. We speak of such events as occurring by Chance ; but, the more broad and accurate knowledge becomes, the more it is evident that events are orderly occurrences and capable of prediction. They appear to occur by chance, only because we do not know their causes or the laws which represent their actions. With infinite knowledge, all thought of chance would disappear. Explanation of Phenomena and Laws. — A physical phenomenon or law is said to be explained or accounted for when it is shown to be a particular case of some more fundamental law or group of laws. By way of illustration, we EXPLANATION OF PHENOMENA. 5 find that objects tend to fall toward the earth. We ask why — that is, we seek an explanation. Sir Isaac Newton, by a study of the motion of bodies, including that of th& moon and planets, was led to deduce the law known as that of universal gravitation, viz., that every particle of matter tends to approach every other particle, the amount of the tendency depending on the amount of matter in the particles and on their distances apart. The tendency of objects to fall toward the earth is, then, a particular case of universal gravitation, and is therefore explained. But we do not know why every particle tends to approach every other — that is, we have as yet no explanation of universal gravitation ; we do not know any more fundamental law to which to ascribe it. Thus explanation in any case only carries us a step farther back; but that step is often of great service. Without it, knowledge would be fragmentary and disconnected. Theory. — Hypothesis. — There are many phenomena and laws which we are not yet able to show to be special cases of more fundamental known laws — that is, to explain ; but in the effort to find explanations we are continually forming suppositions and testing them to see whether they appear to afford the explanations desired. These suppositions in their earliest stages are often very crude and imperfect, and are then called Hypotheses. As they are more and more completely developed, and are shown to be more trustworthy or more probable, hypotheses are called Theories. A hypothesis is developed into a theory by continued comparison with new facts, and by being corrected if necessary to correspond with them. The theory is verified and developed in the same way, and may eventually become so well confirmed as to be regarded as a highly probable law. One of the best tests of a theory or law is to predict what would occur under certain new conditions or at a certain future time if the theory or law proves true, and then to bring about those conditions or wait for that time and see whether the event occurs as predicted. If it does, the theory will be strengthened. If it does not, and we can show that the prediction was correctly made, the theory is thereby proved to be incorrect or incomplete, and should be amended. Thus the verification of the prediction of eclipses, of the apparently very irregular path of the moon among the stars, and especially of the existence of the planet Neptune, all based on the law of gravitation, greatly strengthens our belief in that law. Theories and even crude hypotheses are often of very great service, even when they ultimately prove to be incorrect, for they aid in directing investigation and thus lead up to truth. It is hardly to be supposed that any theory now held will eventually prove to be an absolutely correct expression of the truth to which it relates ; but theories are at present none the less indispensable. QUESTIONS.— What are the fundamental things about which we learn in the study of Physics ? Does physics have anything to say as to the origin of matter ? of motion ? of life ? What forms the physical universe ? Does this universe exist outside of our own thoughts ? How do we perceive it ? What are our senses ? What enables us to separate truth from error in our observations f Define qualities ; a phenomenon. What constitutes the science of Physics ? How does a science differ from a mere catalogue of facts and phenomena ? What has been observed in regard to the tendency of objects to fall ? Why is this not a law ? State the law derived from this observed fact. Are any physical laws supposed to be certainly true ? Why ? For what reason do we have any confidence in them at all ? Illustrate cause and effect. What do we mean by saying that an event occurs by chance ? To a mind knowing everything, could there be such a thing as chance ? How, then, can any one believe it possible that the whole universe exists as a matter of chance ? What do we mean by explanation ? Does explanation explain ? What is the relation between theory and hypothesis ? DEFINITIONS CONTINUED. Physics, or Natural Philosophy, is that branch of human knowledge which deals with all objects, phenomena, and Jaws of the material or physical universe. In the physical universe we come to recognize two, and only two, things which seem to be indestructible, and thus to exist entirely independently of us or of any operation of our senses or reason. These two things are Matter and Energy. Hence, Physics has been also called the science of matter and energy. THE IDEA OF TIME. 7 While physics neither denies nor affirms that there is something in the universe other than matter and energy, no complete discussion of such questions is possible without an adequate knowledge of the laws of this science. Physics, as thus defined, is given its broadest scope. It includes almost all branches of science except mental science ; but the term is generally employed in a much more limited sense. Those sciences which deal with classification only (as most of the natural history sciences), with phenomena where substances undergo changes in their properties (chemistry), or with phenomena which occur in living be ings (biology) — are usually understood to be excluded when the term physics is employed. There are also certain branches of physics proper which are more or less distinctly separated, or are not usually treated in text-books upon physics. Such are astronomy, which deals with the stars, sui\ planets, nebulae, comets, etc., their positions, motions, and laws ; dynamical geology, which treats of the structure of the earth ; etc. The relations between physics, even in the more limited sense, and chemistry and biology, are extremely close. Many chemical and biological phenomena are almost purely physical, and this is true to such an extent that, without a knowledge of a large part of physics, little progress can be made either in chemistry or biology. Time. — The earliest idea of Time probably comes from the recognition of the fact that one event occurs after another. If your memory were perfect, you could mentally place all events in your own experience in the order in which they followed one another in time ; but it would be impossible for you to compare correctly two intervals of time between different events. By experience, however, you have found that there are certain natural processes which appear to go on in a uniform or rhythmical manner, such as the succession of night and day, of winter and summer, the apparent motions of the sun, stars, and moon, the swings of a pendulum, the flow of water through an orifice. By referring events to such processes, you can arrange a system by which the order of succession of all events and the relative intervals between them can be expressed. In the actual measurement of time, we make use of the period of the earth's revolution around the sun to mark the longer interval of a year, the rotation of the earth on its axis to mark the day, and the beats of the pendulum to divide the day into parts. Space. — We are accustomed to think of material objects as occupying definite positions with reference to one another — that is, as being at certain distances apart in certain directions. We understand that this is what is meant when we refer to the relative positions of bodies in Space. In thinking of the distance between bodies, we do not conceive it as depending upon any material thing between them. Our idea of their distance apart would not be changed if we thought of them as separated by no material medium like air or water. This abstract idea of distance, or, as we may express it, of length, breadth, and depth, without any regard to the presence of matter, forms the basis of our idea of space. " Absolute space is conceived as remaining always similar to itself and immovable. The arrangements of its parts can no more be altered than the order of the portions of time. To conceive them to move from their places is to conceive a place to move away from itself." Relative Character of our Knowledge of Time and Space. — There is nothing to distinguish one portion of time from another except the different events which occur in each. Similarly, there is nothing to distinguish one part of space from another except their relation to the places of material bodies. We can not describe the time of an event without referring to some other event, or the place of a body except by reference to some other body. All our knowledge of both time and space is therefore essentially relative. Think, for instance, of our method of stating the time of an event. We say that something occurred in 1776 A. D., on the 4th of July. We mean, first, that it occurred after the birth of Jesus Christ ; secondly, that it occurred after that event by an interval measured by 1,776 whole revolutions of the earth about the sun and by a certain fraction of another revolution. Thus we ordinarily reckon the time of events MATTER DEFINED. 9 relatively to another (or standard) event, the birth of Christ, and by means of an event which is being continually and regularly repeated, viz., the revolution of the earth about the sun. In locating bodies in space, no such universal point of reference is used as in time. Bodies or places upon or near the earth's surface are described as being at a certain distance in a certain direction from any convenient starting-point. The exact location of any point of the earth's surface for precise work in geod'esy, geography, and astronomy, is given by latitude, longitude, and height above the sea-level. Latitude is measured by angular distance north or south of the equator ; longitude, by angular distance east or west from a meridian chosen at will, as that passing through Greenwich, Paris, or Washington. Height above the sea is the vertical distance of the point above the mean level of the ocean. (See. Appletons' Higher Geography, page 6 ; Appletons' Physical Geography, page 19.) Matter. — On all sides of us are -objects, some natural, some artificial. They are earth, water, and things made of wood, metal, woolen and cotton fibers, paper, stone, clay, etc. Not only can you see these objects, but you- can feel their form by touch, and appreciate through the so-called muscular sense their hardness or softness, weight, etc. Many of them can be smelled or tasted ; some can be heard giving out sounds; others are producing heat, light, electrical and magnetic effects. These objects are made up of substances which are either solids (wood, metal, stone, ice), or liquids (water, alcohol), or gases (air, nitrogen, oxygen). The only way in which we can learn about them, or find out that they exist, is by means of one or more of our senses — that is, through sight, touch, and the muscular sense, smell, taste, hearing. Some of them we can perceive in various ways ; others, through only one or two of the senses. something hard, it will be set into vibration and emit sound which can be heard. Air, on the other hand, is transparent, so that it can not be seen ; it can not be perceived by the sense of touch in the same way as a solid. But when it is in motion it is called wind, and this we can feel pressing against the body ; • or when we are moving through air rapidly, as in running or riding, we always experience its pressure. Pure air has no odor or taste, but may be set in vibration in such a way that we hear sound. Thus, air is a material substance which can be perceived only by certain of the senses. Some gases, as chlorine and iodine, have color, taste, and odor. Study out for yourself the senses by which various objects and substances about you can be perceived—water, salt, glass, leather. What sense tells you whether an object is wet or dry t Every object, body, or substance, which can be perceived through at least one of the senses, is a material object, body, or substance — that is, it is made up of Matter. Matter is that of which every conceivable substance is composed. A definition ordinarily given is that matter is anything which can be perceived by the senses. This definition will serve well enough for the present state of your study. It is objectionable, because some of the sensations which we receive from matter (like heat) are due to the energy possessed by the bodies, and not to the matter solely. Kinds of Matter. — Elements. — Are all objects and substances made up of the same kind of matter, or are there different kinds ? Examination shows that the substance of which some are composed appears very different from that of others. Chemistry teaches that almost all these substances are compounds — that is, they may, by chemical processes, be separated into substances which are simpler, and these in turn may be further separated. But there is a limit to this process, for chemists find that they soon arrive at substances which can not by any known physical or chemical process be separated into others. These are then considered as simple or elementary substances, or kinds of matter, and are called the Elements, or the Chemical Elements. At present, there are about seventy elements known. It is possible that some of the substances now thought to be elements may in the future be resolved into simpler ones, and it is conjectured that all may eventually be shown to be built up of only a single kind of matter. Mass, or Quantity of Matter. — Lift in succession several objects — for instance, this book, a stone, a glass of water, a chair, a bit of paper. Ask yourself whether they all seem to contain the same amount or quantity of matter. Of course, you do not know the process of finding out how much each contains, but the objects are so different in weight, size, form, etc., that you at once infer it to be impossible for them all to contain equal quantities of matter — and in fact they do not. Suppose, again, that from the same stick of wood you cut off two pieces, one much larger than the other ; will they contain equal quantities of matter? Obviously not. Different objects, then, contain different quantities of matter. When we wish to speak of the quantity of matter contained in a body, instead of using this long phrase, we say its Mass. Mass, then, means merely quantity of matter. If an object A contains twice as great a quantity of matter as an object B, then the mass of A is twice the mass of B. How mass is measured, will be shown later. Density may be defined as the quantity of matter contained in a- unit volume of any body or substance. Different bodies may contain different masses in the same volume, and therefore have different densities. If we were to take portions of equal volume (say a cubic inch) of different substances — lead, wood, iron, air, water, ice — then these equal volumes would contain quite unequal quantities of matter. If we had a means of measuring these quantities (weighing will do it, as will be explained), we should know the densities of the different substances. The ratio of the density of any substance to the density of water is called its Specific Gravity. The process of determination of density and specific gravity will be treated more fully hereafter. Any body which is of the same density in all its parts is called homogeneous. Molecules. — All substances are supposed to be constituted or built up of parts which are extremely minute, far too small to be seen. Such parts are called Mol'ecules. The molecules of one kind of substance are supposed to be all alike, but those of different substances are diiferent. The single molecules are assumed to be in turn built up of smaller parts, which are called Atoms. The molecules are supposed not to be actually in contact as the individual pellets would be in a tumbler filled with shot, but to have spaces between them which are quite large as compared with the size of the molecules themselves. The molecules are further believed to be continually bounding to and fro at great speed, striking against their neighbors, and thus keeping open for themselves this space which surrounds them. These ideas and some of the reasons for them will be more fully discussed farther on. QUESTIONS.— What does Physics include in its broadest meaning ? Why is it called the science of matter and energy ? What does Physics deny or affirm respecting the existence of anything but matter and energy in the universe ? Why does Physics not enter into mental, moral, and religious questions ? Does it deny the importance of these questions ? How do we arrive at our first ideas of time ? How is time actually measured ? What is your idea of space ? Why are time and space, as we can know them, purely relative ? Illustrate. Give examples of matter, and explain how you recognize matter. Is water matter ? Is air ? Are the odorous particles diffused through the air when roses are brought into the room ? Can you perceive anything by your senses which is not matter ? How is an external world known to us ? Of what does touch inform us ? Of the exact form, size, and distance of bodies. What are appreciated by the muscular sense ? Weight, resistance, etc. On what does this sense to a great extent depend ? On, the muscular nerves. How many senses have you ? Enumerate them, and specify the part each plays in revealing an objective world. Define the term Matter. Are there different kinds of matter ? How many ? In what way are they discovered ? State your idea of Mass. Define and illustrate Density. Do we know how matter is built up ? How is it supposed to be constituted ? What is a molecule ? An atom ? Are molecules in contact ? AND COMPOSITION. When we locate the position or describe the motion of an object, we have to consider the position or motion of its parts. It is therefore simpler, in first treating of motion, to deal with a material particle only, or a portion of matter so small that for the purposes required we need not consider its parts, but may treat it simply as a whole. The following paragraphs contain definitions and propositions regarding mere motion, without any reference to the bodies moved, or to the forces or energy causing the motion, or produced thereby. They really pertain to a branch of pure mathematics and not of physics ; this is called Kinematics (kin-e-maf ics — from a Greek verb meaning to move). The propositions and definitions are deduced for application afterward to material bodies and systems. Direction. — If we draw any straight line upon this paper, as, for instance, the line A B, we may think of it as having a certain direction. We mean that it makes certain angles with certain other lines, real or imaginary, to which for convenience we may choose to refer it. For instance, the line A B makes an angle of thirty degrees with the top edge of the page, and another of sixty degrees with the side. Direction is necessarily relative for the reason that there can be no fixed points in space to refer to. We say that any other line has the same direction as A B when parallel to it. Thus, the direction of a line drawn through the point C parallel to A B would be the same as the direction of A B, and vice versa. Any two lines drawn through one point, and having the same direction, must of course coincide. If a particle were moving from A in the direction of a line A B, it would move along that line so long as it continued to move in that direction. If a particle were at C, it could mov.e in the direction of A B by moving in a straight line through C, and parallel to A B. 14 KINEMATICS. Two particles moving in parallel lines are thus said to move in the same direction. Two particles moving toward the same point are not said to move in the same direction unless the point be infinitely distant, because otherwise they can not be moving in parallel lines. Position. — The position of any point A (Fig. 1) at a given instant of time is said to be known when its distance and direction from some suitable point B, used for reference, are known. To show the direction, we may draw a line from B to A, and state that the direction is that of this line B A ; or we may state the angle which the line B A would make with certain other lines or planes used for reference. Sometimes we locate a point by stating its perpendicular distance from three reference planes at right angles to one another. Thus, a point in a room may be located by stating its perpendicular distance above the floor, its distance from one side, and its distance from one end of the room. From what has been said regarding our idea of space (page 8), we see that no part of space itself is different from any other part, so that there is no point in space which we can select as a starting-point. We can not, therefore, locate the position of a particle in space absolutely. All that we can do is to locate it with reference to some other particle — that is, to locate it relatively by methods just shown. C occupying time in doing so. The particle is in motion only so long as it is continuously changing its position along the path — that is, so long as its position at the end of any interval of time, however short, is different from that at the beginning. "We also know that the path traveled over must be continuous — that is, can have no gap. For a gap would mean that the particle was nowhere at that instant, which is impossible. MOTION. 15 Note that the object is in motion only when continually changing position, and that position means merely distance and direction from any convenient object chosen for reference. Observe also that this reference object is selected without regard to whether it is itself in motion (as it always is) or not, but simply for convenience. Watch a ball moving through the air. It is continuously changing distance and direction from some point on the ground. We do not in such a case stop to consider that the ground is a part of the earth which is whirling on its axis and around the sun. This means that the car is continuously changing its position relatively to the ground, but that you are not changing your position relatively to the car. You see at once that relatively to the ground you are in just the same motion as the car, at the same time that relatively to the car you are not moving. Thus, you are either in motion or not in motion, under precisely the same actual conditions, according to the object to which you refer the motion. Similarly, by referring your motion to a car ahead of you which is going faster, you say that you are losing on that car, meaning that relatively to it you are going backward. Hence — Motion is purely relative, both in speed and direction. There is no such thing as absolute motion, because there is no fixed point in space (page 9). Rest. — When a particle at a given instant is not in motion with reference to some point selected for convenience, the particle is said to be at rest. But at the same instant, with reference to some other point, the particle is in motion ; thus, by properly choosing our reference point, the motion may be as fast as we please, and in any direction. All that the term Eest really means is that relatively to the chosen reference-point the particle is not changing position at the given instant. When in every-day language we speak of an object at rest, we simply mean that it is not moving over the surface upon which it stands. Rest, then, is not a condition different from motion. It is only the special case of motion where the body and reference point happen to have the same motion at the same time. Whenever, therefore, we make a statement about a body at rest, we must not think of it as re- ing otherwise than in degree from that of a moving body. The Direction of Motion of a particle at any given instant is the direction of its path at that instant. If the path is a straight line, its direction is, of course, that of the line. If the path is curved, its direction at any point is that of the tangent to the curve at that point (a line which touches but does not cut the curve). Let ABODE represent the path of a moving particle. Suppose the part C D of this path to be straight. When the particle is anywhere between C and D, its direction of motion is C D. At any point B of the path, draw a tangent F G. Then the direction of motion of the parti cle at B is that of the line F B G. Though the direction of the particle is continually changing as it passes B, we still say that its direction at the instant when it is at B is F G. and this is true in the same sense that in geometry the tangent is said to represent the direction of the curve at the point of tangency. The path in Fig, 3 appears to be all in the plane of the paper, but it is meant to represent any very crooked path not in one plane. Bend a piece of wire, and study out the direction of motion of your pencilpoint as you move it along the wire. The Terms Uniform and Constant will be frequently used. To some extent they are employed to represent the same idea, and are therefore used interchangeably ; but there is a distinction to be observed between them. We speak of a thing or quality as being uniform, implying that it is the same, wherever we are dealing with it. Thus, we speak of a uniform surface, shape, color, motion. A quantity is said to be constant if it has the same amount or value whenever we meet it ; for example, a constant height, a constant speed. Thus uniform is used mainly with reference to things or qualities with respect to place, and constant with reference to quantities in respect to time. QUESTIONS.— What is meant by a material particle ? Why do we deal with a particle instead of a body in kinematics ? Mention the subjects of kinematics. How do we state the direction of a line ? Can we state the absolute direction VELOCITY, OR RATE OP MOTION. if of a line ? Why ? When do two lines have the same direction ? How can two particles not moving in the same line move in the same direction ? How do we define the position of a point ? Can we state the absolute position of a particle in space ? Why ? Define motion. What do we mean by the path of a moving particle ? Why must the path moved over by a material particle be continuous ? Show how motion is purely relative. If we speak of a car as moving along its track, to what do we refer the motion ? Does this affirm anything about the motion of the car relatively to any other object ? Is a body at rest relatively to the ground in any different absolute condition with respect to the sun, for example, than a body which is moving over the ground ? Are we, then, to think of rest as indicating anything whatever as to any absolute condition of the body ? Is there any such thing as absolute rest or absolute motion ? Are we, then, to think of starting a body from rest as any different from making it move faster when already in motion ? What do we generally mean when we speak of a body as at rest ? Why do we commonly refer motion or rest to the ground ? If a particle is moving along a curved path, what is its direction at any given instant ? What distinction is to be observed between the terms uniform and constant ? Speed. Constant Velocity, Uniform Motion. — If the motion of a particle is such that in equal intervals of time, however short, the lengths of path traversed by it are equal, the particle is said to be moving with a Constant Velocity or Uniform Motion. The motion may, of course, be over any path, either straight or curved, regular or irregular. As the spaces gone over are equal for equal time intervals, it follows that for two such intervals the distance gone over would be twice as great as for one ; for three, three times as great, etc. In other words, when a particle moves with constant velocity, the distance gone over in any given time is proportional to that time. For uniform motion, the velocity is expressed by stating the distance moved over in a unit of time. Thus, velocities would be stated as 7 miles an hour, 3 feet a second, 2 metres a second, large units being usually chosen for convenience for great velocities. If we could measure the actual distance passed over by the particle in one second, this would evidently give its velocity directly. It is, however, seldom convenient to do so; but we know that the space gone over is proportional to the time occupied. Thus, if the particle moves over 3 metres in one second, it would in 001 second move over 0-01 of 3 metres or 0-03 metre. Conversely, if it moved over 003 in one second, and the same would be true, however small the fraction of a second. Hence we may say that for uniform motion the velocity is stated by the ratio of the distance traveled to the time occupied. ond. The same velocity would have been found if we had measured the space traveled in a millionth of a second or in a year. Thus, we can find the velocity, even if the particle does not continue to move for a unit of time, but only for a very small fraction of a second, or even if the velocity is continually changing. If a particle is moving with a uniform velocity of 7 feet a second, it will in 3 seconds pass over 7X3 = 21 feet ; in 05 second, over 7 X 0-5 = 3'5 feet, and so on. In general, if V represents the velocity and t the time during which the body moves, the space S, or distance gone over along the path, will be Average Velocity. — If a particle moves with a changing velocity (as, for instance, a railroad train does, going now faster, now slower, stopping, and starting again), we may find it convenient to speak of its average velocity. This could be found if we knew its actual velocity at each instant, and then averaged all these velocities. The average form velocity. Acceleration is continual change of velocity. If the velocity of a particle is increasing, the acceleration is called positive, or -j- ; if the velocity is diminishing, minus, or — . For convenience, negative acceleration is generally called retardation, and acceleration is in that case understood to mean positive acceleration. In what follows, the term acceleration should be understood to include both positive and negative, unless otherwise specified. Thus, if a moving particle in successive equal intervals of time, however short, passes over unequal distances, its motion and velocity are no longer uniform, but are accelerated. If the spaces passed over in successive equal intervals of time are greater and greater, the velocity is increasing, and the particle is receiving" positive acceleration ; if they are less and less, the particle is receiving negative acceleration, or retardation. Acceleration, like position and velocity, and for the same reasons, is purely relative. There is no such thing as absolute acceleration. It is very important to remember that, if the velocity of a particle is in the slightest degree changed, acceleration must have occurred during the change ; also, that if a particle has been " set in motion," it has been accelerated. The rate at which the velocity of the particle is being changed is known as the Rate of Acceleration. It is usually spoken of as acceleration only. Constant Acceleration. — Uniformly Accelerated Motion. — If a particle is moving along any path in such a manner that its velocity is increased (or diminished) by equal amounts in equal times, the acceleration (or retardation) is constant, and the motion is said to be uniformly accelerated and motion are variable. We have a multitude of examples in nature of accelerated motion, and a few important ones of constant acceleration. Any heavy body allowed to fall freely toward the earth moves with a uniformly accelerated motion. Its velocity increases at the rate of 9!8 metres, or 322 feet, a second. Laws of Uniformly Accelerated Motion. — Let a denote the rate of acceleration — that is, the increase of velocity a second. Then, if the particle starts from a state of rest, its velocity at the end of one second will be a units, at the end of two seconds 2a units, and so on. If t = the time in seconds after starting, the velocity v at the end of this time This law may be expressed as follows : The velocity at the end of a time £, due to the acceleration, will be equal to the product of the rate of acceleration and the time. For example, an object falling freely toward the earth has an acceleration a = 32-2 feet a second. Its velocity at the end of 3'5 seconds would then be v = 32-2 x 3'5 = 112'7 feet a second. The law as to the space traveled by a uniformly accelerated particle may be thus stated : The space s traveled in a time t is equal to one half the product of the rate of acceleration and the square of the time, or s = -j-atf. It has just been shown that the velocity at the end of the time t will be v = at. The velocity has been increasing from zero at a uniform rate; hence the average velocity is \at. If the particle had moved uniformly with this average velocity for the same time t, it would have gone over a distance \at x t = ^aP, and this would have been the same as that actually traveled under the accelerated motion. Combined Uniform and Accelerated Motion. — Suppose a particle moving with a uniform velocity F, to receive an acceleration a in the same direction as F, what would be its velocity at the end of t seconds ? The acceleration would of itself produce a velocity v = at in that time. What would be the space traversed in the time tff Under the uniform motion alone, it would be Vt. Under the accelerated motion, it would be one half the product of the rate of acceleration and the square of the time. If the two motions were in the same direction, the space traversed would be the sum of these. If the motions were in opposite directions (retarded motion), the change in position would be the difference of the two. QUESTIONS.— Define velocity. Describe constant velocity and uniform motion. How is the amount of constant velocity expressed ? How is it measured ? Deduce the formula for the space passed over in a time t with a constant velocity V. If a steamer moving uniformly goes fifty miles in four hours, what is its velocity ? If it does not move uniformly, but stops several times, what is its average velocity ? If a bullet were to start with a velocity of one thousand feet a second, how far would it go in three seconds, if it continued to move uniformly ? How long would it take to go a mile ? Define acceleration. Distinguish between acceleration and retardation. Can absolute acceleration be determined ? Why ? Does accelerating a body which is at rest differ in any way from accelerating one which is already in motion ? If a body is " started " or " set in motion " from rest, is it accelerated in so doing ? Describe constant acceleration. Does retardation differ in nature from acceleration ? Deduce the formula for uniformly accelerated motion ; for combined uniform and accelerated motion. COMPOSITION OF MOTIONS. Illustration of Composition. — Suppose that you are sitting at A, Fig. 4, in a car moving uniformly along, and that you are holding still in your hand a ball. The ball then possesses the same onward velocity as the car relatively to the earth, but is at rest relatively to the car. Eoll the ball straight across the car to a person sitting directly opposite to you, at C. To do so you would, of course, aim it and roll it just as you would if the car were stationary. You know from experience that it will go across in exactly the same way in either case, or, in other words, that its motion across the car is independent of the motion of the car itself so long as the car is moving uniformly. The motion of the ball, then, relatively to the car, is in a straight line at right angles to the length of the car. If the car is moving, then the ball possesses two motions, that across the car and that of the car. We will assume both to be with constant (but not necessarily the same) velocity. What, then, will be the actual motion of the ball relatively to the ground or track, as, for instance, you might see it if you were standing in the street ? This is a single example of a multitude of such combinations of different motions which are continually occurring about us at every instant. It is essential to see how we may study out such cases. We will take this up, then, as a study of pure motion. Resultant of Two Uniform Motions. — Suppose a free particle to be moving with a uniform velocity along a straight line ABC, and at any moment, as when it is at B, another motion to be imparted to it which, if the first motion did not exist, would give it a uniform velocity in the direction B D. What will be the resulting actual motion ? It is found from all experience that the particle will in any given time have moved just as far away from the line A C as it would have moved along B D if the first motion had not ex- isted. The actual position of the particle will not be along either B D or B C ; but it will have moved as far from the line B D as if only the first motion had existed, and as far from the line B C as if only the second motion had existed. To state the case a little more completely, we must remember that any two lines have the same direction when they are parallel. Then, at any given instant after leaving B with both motions, say when it has D/ B D, but along some line which is found by experiment, and which will presently be shown to be the straight line joining B with e. The actual motion is called the resultant motion, and the actual velocity the resultant velocity. If, then, a particle be simultaneously affected by two or more motions, the amount of change of position produced in a given time by each motion, measured in its own direction, is as great as if no other motion were present. of Motions, and will now be described. , Parallelogram of Motions. — Suppose a particle at A, Fig. 6, to be given simultaneously two such uniform motions in straight lines that in equal times the motions acting separately would bring the particle to B and to C. If they act together, the first would change the position of the particle by a distance equal to A B, measured parallel to A B and from the line A C ; the second would change the position by an amount equal to A C, parallel to it, and measured from A B. Draw the lines C D and B D, parallel to A B and A C respectively. This will complete the parallelogram A B D C. Then D will be the actual position of the particle at the end of the time. must be at K, formed by completing the parallelogram A E K H. At the end of the second, the particle must be at L, similarly formed, etc. Hence, the particle in its actual motion must pass along the line A D, the diagonal of the parallelogram. If a particle be simultaneously given two uniform motions, we may find the resultant motion as follows : Draw through a point lines parallel to the direction of the two separate motions. Lay off on these lines lengths proportional to the spaces over which the particle would move in equal times. Complete the parallelogram and draw the diagonal from the starting-point. The particle would then move along this diagonal at a uniform rate, and in the same time that it would move over either side. The diagonal is then said to represent the resultant motion in direction and amount. A person rowing a boat across a stream flowing with a rapid current, and heading always at right angles to the shore, will reach the farther bank far below the point opposite to which he started. The resultant motion will be diagonally across the stream, being compounded of the forward motion of the boat and the downward motion of the stream, which carries the boat with it. Similarly, a sail-boat with a side-wind does not reach the point it heads for, because the boat drifts sidewise with the wind, besides moving forward. This sidewise motion is called leeway. The resultant motion is therefore diagonal, and not straight ahead. In both cases, allowance for leeway has to be made by pointing the boat, if possible, enough farther up-stream, or into the wind, to cause the resultant motion to have the direction in which it is desired to move the boat. Resultant of Several Uniform Motions. — If a particle be simultaneously given more than two uniform motions in the same plane, we may find the resultant of them all by first combining any two ; then their resultant with a third ; etc. sultant motion would be uniform along the straight line from A to E. Representation of Velocities by Diagrams. — Suppose that we wish to indicate by a diagram that a body is moving in a straight line with a uniform velocity of 15 feet a second. Through any convenient point A on the paper, a line should be drawn in any convenient direction AC. At a distance of 15 units from A (fifteen eighths of an inch), a point B should be marked off. If a second motion is to be represented, another line A D should be drawn, making the same angle with A C that the direction of the second motion made with the first. Along this should be laid off in the same units a number to represent the second velocity; for instance, if this is 11 feet a second, a point E should be marked off, so that A E equals eleven eighths of an inch. It is clear, therefore, that A B and A E can be laid off to represent velocities — i. e., rates of motion or motions per units of time — as well as motions merely. Composition of Uniform Velocities. — It has been shown how velocities can be represented by lines and diagrams just as mere motion is represented, the only difference being that a unit along the line stands for velocity — i.Q.^feet per second or metres per second — instead of mere change of position — i. e., feet or metres. All the foregoing statements as to the composition of motion apply, therefore, to the composition of uniform velocities. Composition of Uniform Accelerations. — If we make the direction of the lines such as to represent the direction of the acceleration and the lengths of the lines proportional to the rate of acceleration, then the resultant acceleration will be found precisely as the resultant velocities or motions are found. Resolution of Uniform Motions. — Two Components.— Suppose that a particle at A moves uniformly in the direction A B, reaching B in a certain time ; and suppose, further, that we do not know anything about the cause of the motion. Then this motion may have been produced by the combination of several motions simultaneously impressed upon the particle. know that a particle at A, simultaneously given the motions A C and C B, would move over A B. Hence, you know that a motion A C in the direction of P, combined with another, C B, in the direction of N, will produce the given mo- resolving the motion into component motions. It is important to remember that the motion is always understood to take place in the direction indicated by the order in which the letters denoting the line are written. Thus, motion along A B would mean from A toward B ; along B A, from B toward A. Several Components. — By methods based upon those for the composition of several motions, it is possible also to resolve a given motion into any desired number of components in any desired directions. A motion may be regarded as being made up of the simultaneous motions obtained by this process of resolution, for it is in every way precisely the same as if it were so made up. QUESTIONS.— Draw on the blackboard a diagram representing the path of a ball rolled across a moving car. Explain fully why the ball takes such a course. What do you mean by resultant motion ? Illustrate by diagram. Define resultant velocity. What is Composition of Motions ? Describe and apply the parallelogram of motions. Illustrate in the case of a boat crossing a rapid stream or a sail-boat running across the wind. How can you find the resultant of several motions ? What is meant by resolution of motions ? Illustrate by figure. What is possible where there are several components ? MISCELLANEOUS QUESTIONS AND PROBLEMS. If a train of cars is moving uniformly at a rate of 20 miles an hour, how far will it go in 5 hours ? In 3 days ? How long will it take the train to go 1,000 miles ? If it traveled 520 miles in 20 hours, moving uniformly, what was its velocity ? Wild pigeons have been shot in the latitude of Albany, N. Y., with Carolina rice undigested in their crops. About what must have been the velocity of their flight ? (Apply scale to your map of the United States.) A particle starting from rest and given a uniform acceleration of 50 feet a second would have what velocity at the end of 20 seconds V = 50 x 20. What distance would it traverse in this time ? Ans. 10,000 feet. 28 ENERGY. If a particle moving with a uniform velocity of 500 feet a second were to be given an acceleration of 50 feet a second in the direction of its motion, what would be the velocity at the end of 20 seconds ? v'= 500 + (50 x 20). If the same acceleration were imparted in the opposite direction, what would be the velocity at the end of 3 seconds ? v"= 500 - (50 x 3). What at the end of 10 seconds ? v"= 500 - (50 x 10) = 0— i. e., it would have been brought exactly to rest. What at the end of 20 seconds ? v" =500- (50x20)= - 500— i.e., the par ticle would be moving in the opposite direction from that at the outset. Uniform velocities of 10 feet per second northward and 5 feet per second eastward are simultaneously given to a particle. Draw a diagram by the parallel ogram of velocities, which will show the relative direction and magnitude of the resultant velocity. NATURE OF ENERGY. Work and Energy defined. — There are two fundamental terms — energy and work — which are used in physics in very nearly the same sense as in every-day speech. In arriving at their scientific meaning, we shall begin by considering the ideas which they commonly represent to us. When we say that a man has much energy, we mean that he has much capacity for doing work. By this we may imply bodily work or mental work, or both ; but in our present study we are not concerned with mental phenomena or exercise of the will, so we need think only of the man's muscular energy and of the work which he can do with his body. In physics, when we say that an inanimate object or portion of matter has energy, we mean that it possesses capacity to perform physical work.* Thus — Energy is capacity for doing Work. * Energy is often spoken of as the power of doing work, or simply as power The term power, however, has a special meaning assigned to it in physics, and should not be used in this connection. (See page 101.) It will be found as we go on that there is reason to believe that whenever a body (that is, a portion of matter large or small) performs work, it does so by accelerating the motion of other portions of matter. In many cases, this acceleration is visible ; in others, it is shown only by close study ; in others again, it is only supposed (with more or less probability) to be the fact. By way of illustration of the first class of cases, find some heavy object which will roll easily — a large wooden ball, a cannon-ball — anything that will move with little friction. Select a smooth, level surface on which you can roll it. The more massive the object and the smoother the surface, the more convincing the experiment will be. Let us take a heavy ball on a smooth floor. Begin with the ball at rest ; then with it in motion. Accelerate it by pushing it. In order to do so, you will have to exert muscular effort in a manner which you will recognize as what is familiarly called •" doing work." Repeat the experiment in a variety of ways. You will invariably find that to accelerate the ball you must perform work upon it. This is a universal principle. It is found also to be true that the amount of work done to produce a given acceleration in a given object is the same at whatever velocity the particle is already moving ; for instance, to accelerate its motion by 10 feet a second would require no more work if the object is moving a mile a second than if its velocity is only a foot a second, or if at the outset it was zero.* Take another familiar example. Throw a ball horizontally. All the time the ball is in your hand you are pushing it forward by the hand and continually accelerating it. You will recognize by your feel- * The student will find the whole subject much clearer and more interesting if he will try for himself the experiments suggested. The teacher should see that this is done in every case where possible, and should encourage the pupils to describe in the class-room their own experiments. Learners will find it much easier to remember the subjects they study if they will talk them over among themselves at unoccupied times out of school, and plan to work together upon experiments at home. It is by no means necessary that the apparatus should be exactly that here described. The spirit and habit thus acquired of trying things for one's self and of taking nothing for granted that can be tested by experiment, will be of untold value through life ; while the ingenuity developed in constructing apparatus, in using tools, and especially in adapting things at hand to the purposes desired, must prove a most desirable acquisition. that you are doing work during each throw. In each experiment you should be able to discover that you are doing work so long and only so long as you are increasing the velocity of the object— i. e., producing acceleration. If the ball had been set in motion by some inanimate material body, that body would have accomplished the same result as you. It would, therefore, have performed work. A body is performing work whenever, and as long as, it is causing acceleration of any other portion of matter. When a body A is accelerating another body B, we say that work is being done by A and upon B. Inertia. — As the result of all sorts of experiments upon all kinds of material objects, it appears that no particle of matter of itself is capable of changing in the slightest degree either the direction or velocity of its motion. This is briefly expressed by saying that matter is perfectly inert. By this we do not mean that a given particle is not in motion, but simply that it has no capacity of itself to change its rate or direction of motion — that is, if it is moving relatively to its surroundings it can not of itself change its direction or speed, or if it is at rest relatively to them it can not of itself start into motion. From this statement and the foregoing experiments, it follows that a material particle can be accelerated only by the performance of work upon it by some other object. To be able to do work, this other object must possess energy. Whenever, then, a particle of matter is being accelerated, work is being done upon it by some other portion of matter possessing energy.* This fact is of the utmost importance to any clear comprehension of the laws of Physics. * The above is not true in a general sense of a body of matter, for the individual particles always possess some energy relatively to one another which may act (in the case of a heated body) in such a way as to change the direction and velocity of the body by expanding it, or otherwise. The statement is true, how* ever, of any body as a whole so long as it retains its size and form. Three statements, called the three LAWS OF MOTION, were given two centuries ago by Sir Isaac Newton in his classic work, the Principia. They stand to-day without change as presenting the current ideas on the same subjects. The first law, virtually a statement of this property of matter, is as follows : Just what is meant by force, you will learn later. For the present it will be sufficient if you understand the phrase " by impressed forces " to mean by» the action of some other matter possessing energy. Free Motion. — A body is said to be free to move in a given direction when there is no resistance opposing its motion in that direction. In its widest sense, a free body is one whose motion is unresisted in all directions, and the motion of such a body would be free motion in the broadest sense of the term. A smooth round ball rolling on a truly horizontal smooth surface is nearly free to move in any direction over the surface. Nature of Energy. — A man is able to perform work because he possesses muscular energy. We shall not attempt to consider in what that form of energy consists, but we must ascertain what is the condition of an inanimate object when it possesses energy. In doing so we shall find that matter can possess energy only ~by being in motion. FIG. 10.— Place them on a wide straight crack in the floor or table or on a grooved board, or lay down a couple of planed boards with edges a little apart to serve as guides. The result of the experiment will be more marked if the end of the board toward A is raised very slightly, nearly but not quite enough to have the balls keep in motion of themselves, thus overcoming friction. Start A rolling toward B. When it strikes, B will be accelerated — i. e., if at rest it will be set in motion ; if moving in the same direction as A, it will be made to move faster ; if moving (not too fast) toward A, it will be stopped and set in motion in the reverse direction. All these are merely cases of acceleration of B by A. Place A and B in contact, but both at rest. Neither can accelerate the other. Let A and B roll down the board in actual contact, with the same velocity. Again, neither can accelerate the other. You see, then, that A (possessing energy imparted by you) can accelerate B when it has a velocity relatively to B, and can not accelerate B when it has no velocity relatively to it ; but, to accelerate B, requires that work should be performed upon it. Hence A must have possessed energy relatively to B when it had a velocity, and none when it had no velocity relatively to B. Again, note what the condition of A is after it has done work upon B. Its velocity is much reduced, and may be even zero. A loss of velocity has accompanied the performance of work, and was therefore apparently necessary to it. If B is moving toward A at a certain speed, A may not have sufficient energy to send it backward, but will merely stop it or perhaps only lessen its speed. In this case A will bound back, and the work will therefore have been done by B upon A, as A will have been accelerated while B will have lost velocity. In the first experiment above, the acceleration of B appears to be instantaneous, but in reality the balls are in contact for a time which is reasonable, although so short that we do not easily perceive it. During this time, the velocity of A is diminishing and that of B is increasing. Motion necessary to Energy. — From a multitude of experiments of this sort, the conclusion is drawn that a body in visible motion possesses energy 'because of its motion. Increase of Energy with Velocity. — Roll A with different velocities. The faster it moves, the faster B will move after the blow. To make B move faster requires, as you know from your former experiment in rolling the ball, more work to be done upon it. Hence the greater the velocity of A, the more work it can do, and therefore the more energy it possesses. The less the velocity of A, the less its energy. If its velocity is zero, its energy is zero. Therefore, the energy of a body in visible motion increases with an increase of its velocity. From general experience with all forms of energy, the hypothesis is reached that, just as the energy which we have been dealing with in the moving balls was due to the visible motion of their mass, so all energy of whatever form is due to motion of matter. The motion and even the moving portions of matter may, however, be invisible, owing either to smallness, to the peculiar character of the matter, or to other causes. It is also found, as will be shown, that the amount of energy depends on the amount (mass) of moving matter as well as on its velocity. The property of inertia further indicates to us that energy is a capacity acquired by matter and not inherent in it. Hence it is assumed that — When we speak of a body, then, as possessing energy, we mean that the matter of the body is in motion, either visible or invisible. In other words, we mean that the body itself contains the energy. In contrast to this you will see, as you go on, abundant instances where bodies are performing work (as where a weight runs a clock), but where the energy is not possessed by the body but only transmitted through it. In such a case the energy is imparted to the body by the source of energy, and given up by the body to the thing worked upon. Inasmuch as it is often convenient to use a term which suggests the idea of motion when energy is referred to, the adjective kinet'ic is sometimes prefixed to the word. QUESTIONS.— What do we mean when we say a man possesses energy ? Give the ordinary meaning of the term energy ; the definition of energy as used in physical science. What do we mean in physics by the term body ? What is believed always to occur when work is done ? Is this known always to occur ? Why not ? If you accelerate a rolling ball by pushing it with your hand, how do you recognize that you are doing work ? Can matter be accelerated in any way except by doing work upon it ? If a ball is at rest upon the floor and you set it in motion so that its velocity is one foot a second, is the work done by you any greater or any less than if the ball had been moving with a velocity of 5 feet a second and you had increased it to 6 feet ? How would you explain this from the statements concerning rest as given under Kinematics ? If the ball ia rolling without friction at a uniform speed, do you have to do work to keep up that speed ? When do we say that an inanimate body is performing work ? When do we say that a body is having work done upon it ? Is any particle of matter capable of starting itself into motion ? Of stopping itself ? Of changing its velocity in any way ? Of changing the direction of its motion ? Of accelerating or retarding itself ? What term do we use to express the inability of matter to do these things ? Does Inertia mean anything else ? Suppose a bullet is moving 2,000 feet a second, is it inert ? Suppose that the same bullet is lying motionless on the floor, is it any more or less inert than when moving ? By declaring a body to be inert, do we thereby declare anything respecting its motion ? State Newton's first law of motion. What is meant by free motion ? By a free body ? How is it found that matter can possess energy ? Can it possess energy in any other way ? What does the experiment with the rolling balls show as to the velocity of A with respect to B in order that A should be capable of doing work upon B ? How does this illustrate that a body in visible motion possesses energy ? How that it possesses energy because of its velocity ? If the velocity is greater, is the energy greater or less ? Prove this by experiment. Give the fundamental general hypothesis respecting the nature of energy. Is this based on experimental knowledge, or is it purely a matter of belief ? What do we mean by saying that a body " possesses " energy ? Is the motion to which energy is due always visible ? Is energy due to anything except velocity ? Is energy the same as velocity ? Could an imaginary moving point possess energy ? Can a body transmit energy which it does not possess ? Give an illustration. What is meant by kinetic energy ? What is the meaning of the adjective kinetic ? Is all energy kinetic ? The Kind of Motion, in virtue of which a body possesses energy, makes a difference in the sensations which that energy excites in us, as well as a difference in the effects which it produces when doing work upon other bodies. For this reason, energy is said to exist in various forms. Examples of Forms of Energy. — Of the different kinds of motion, there is, first, visible motion of the body as a whole, moving along through space ; this gives rise to energy of visible onward motion. A body may rotate or spin like a wheel or top, and its energy is then in the form of visible energy of rotation. It may not be in visible motion at all, but possess only invisible motion of its particles or molecules ; its energy is then in the form which is called heat, sound, radiant energy, according to the precise character of the molecular motion. Finally, energy may be in the form exhibited by electrical currents, etc. FORMS OF ENERGY. 35 These varied forms will be considered in detail in the chapters on Sound, Heat, Light, Electricity, and Magnetism. A few examples, however, will be here given in some detail, as it is of the utmost importance to any real knowledge of physics to obtain clear ideas of energy. Energy of Visible Onward Motion. — To prove that a body possesses energy (actual, kinetic) with reference to a given point, we have only to show that its velocity with reference to this point is greater than zero. As motion is purely relative, we must remember that the velocity, and therefore the energy, will be different in amount according to the point to which they are referred, for the velocity referred to one point may be large, to another small. Two cannon-balls fired at the same instant, in the same direction and with the same velocity, would have immense energy referred to the cannon they had left, or to the ground they were moving over, or to the target at which they were aimed. But relatively to each other they would possess no energy at all, because their relative velocity is zero, just as two parts of the same ball would have no energy with reference to each other. A railroad train in motion over the track possesses energy with respect to any object stationary upon the track, or moving more slowly than itself. Witness the destruction produced if the train runs into another which is standing still, or even moving slowly ahead of it. If another train be approaching the first, then the velocity of the two trains relatively to each other is, of course, the sum of their separate velocities relative to the track. Their energy relative to each other is therefore much greater than their energy relative to a stationary train ; while if there are two trains moving in the same direction with the same velocity, they possess no energy relatively to each other, although both have great energy relative to the track and earth. A stone lying upon the ground possesses no energy relative to the ground, but think of the velocity with which the stone is moving, together with the ground beneath it, as the earth spins on its axis once each day, and whirls along on its path around the sun ; and imagine the immense energy it possesses relative to a point not so moving. downward. Pull it aside a few inches in a horizontal direction, and let it go. It will swing to and fro. Notice that, when you release it, it begins to move slowly at first, then more and more rapidly, till it reaches the lowest point of its swing, and then it moves more and more slowly as it rises to the other end of the sweep. There it stops and then begins its return swing. Notice also that it always takes, as nearly as you can tell, just the same time for each swing made. A body suspended and swinging in this way is called a pendulum, and the to-and-fro motion of the stone or " bob of the pendulum " is pendular motion, or vibration. Examine now the energy of the stone. You will see that the instant you release it, arid before it starts, it has no velocity, and therefore no energy. As it moves it gradually gains energy, for its motion is accelerated until it reaches the lowest point. Then it begins to lose velocity, and therefore energy, moving with retarded motion, and so continues until it reaches its turning-point, where for an instant its velocity is zero, and it therefore possesses no energy. The same series of changes is gone through with at each swing. The energy of a body vibrating in this way is called energy of vibration, or vibratory energy. Place a rubber band over the tips of your thumb and forefinger, and keep it stretched by drawing them apart. With the other hand pluck the band near the middle. This will set it in vibration, and it will give out a musical note. The string of any musical instrument will show the same thing. Examine the vibrating side, and you will see that it is in to-and-fro motion. Touch a bit of paper against it, and a buzzing FIG. 11.— VIBRATING BAND. sound will be heard as the band re- peatedly strikes the paper. Each particle of the band is moving with a motion very similar in character to that of the pendulum. Now, the band is a material substance, and you have found that it is in motion. It therefore possesses energy. We refer the motion and energy to the position of the band when at rest. air. The vibrating string imparts its energy to the air, setting the air particles into a similar to-and-fro (pendular) vibration. Pulsations are thus begun in the air which travel off from the band in all directions, much as waves of water travel when a pebble is dropped into a pool. Some of these pulsations reach the ear and cause there the sensation of sound. The particles of air are matter. They are in toand-fro motion when conveying sound. They therefore possess energy just as does the vibrating string itself, and this energy we call the energy of sound vibrations. Sound vibration is thus energy of motion, but the motion, unlike that of the pendulum, for instance, is invisible, and it excites in us a sensation (sound) which the pendulum does not. It is therefore called another form of energy. Heat. — In a body conveying or giving out sound, the molecules are vibrating in a very regular and systematic manner, all the molecules at any given point of the body swinging to and fro together in nearly the same direction and at nearly the same rate. The regularity may be compared to that of the steps of a body of soldiers marching in correct time. But the molecules of all bodies possess, whether in sound vibration or not, another and entirely distinct motion. They are never without some of this motion ; no body has been ever known to be reduced to a condition where it was absent. This motion differs from that of sound vibration in being irregular and unsystematic, when we consider the movement of the individual particles. The molecules are flying to and fro, first in one direction, then in another, no two at once in the same direction, now fast, now slowly, jostling against their neighbors and being jostled in turn. The irregularity of this motion may be compared to that of the footsteps of the individuals in a great crowd of people, no two of whom are trying to move in the same direction or at the same rate of speed. Each molecule at any given instant velocity it possesses energy. Such energy is Heat. The more violently the particles are flying about, the hotter is the body. Now, you easily perceive that heat affects our senses in a manner entirely different from sound, or from the energy of an onward moving body. Hence, heat is another form of energy. Radiant Energy. — Light. — We have reason to believe that all bodies are surrounded by a kind of matter which possesses many properties quite different from those characterizing substances with which we are familiar. This matter is called the luminiferous Ether, or simply the Ether. You will learn more about it when you come to study Light. The molecules of bodies, as they leap about in performing the heat movements, stir up this ether at the points where it is in contact with them, and set its particles into pendular vibration. This motion is passed along in a wave in all directions from the hot body. Each particle of the ether must be supposed to possess mass, and, as it has also this motion, it must possess energy. Such energy is called Radiant Energy. If radiant energy falls upon the skin, it may excite the sensation of warmth. If it is of the right rate of vibration, and falls upon the eye, it excites the sensation of light. It is by means of radiant energy that we are able to see. If it falls upon certain prepared " plates," it produces chemical effects which we make use of in taking photographs. It also stimulates the growth of plants ; and, curiously enough, it has been recently proved that certain electrical effects are propagated through space by this same radiant energy. Notice that of this form of energy we know hardly anything by direct observation. We are acquainted with its effects and its laws ; but we do not even know that there is an ether in the same sense in which we know that air exists. We feel sure that there must be an ether, that it must be material, and that it must transmit energy, because we have various effects which we can explain by these suppositions without violating any of the better known laws of matter. CONSERVATION OF ENERGY. 39 QUESTIONS.— What is meant by the term " form of energy " ? What would be the form of energy possessed by a moving cannon-ball ? By an avalanche ? By an arrow in its flight ? By the earth in its motion through space ? By the earth in virtue of its rotation about its axis ? Give other examples of this form. Do the cars of a train possess any energy of onward motion with reference to one another when moving steadily ? If the forward car is suddenly checked by brakes, a collision, or by running off the track, do the cars behind possess any energy relatively to it ? Two trains are moving with the same speed on the same track ; if in the same direction, do they possess energy relatively to each other ? If in opposite directions ? Show how the swinging pendulum possesses energy ? What is this form called ? At the extreme end of its swing, does the pendulum possess energy ? What is supposed, then, to have become of the energy which is possessed by the moving pendulum ? What is the kind of motion of a violin-string when giving out sound ? What is the energy of this form called ? Why do we call this a different form of energy ? To what do we refer the energy and motion of a vibrating body ? How does the energy of sound vibration differ from that of the pendulum ? Describe briefly this form of energy. Describe briefly the motion constituting heat-energy. That constituting radiant energy. What proof have we of the existence of an ether ? TRANSFORMATION AND CONSERVATION OF ENERGY. Energy indestructible. — When the properties of matter are considered, it will be shown that matter is indestructible, or, in other words, that the quantity of matter in the universe appears to be constant. The same statement is true of energy, but of no other physical quantity. We have seen that energy may exist in several forms. It is also true that energy of any one form may be changed into energy of any other form, or, as we say, may be transformed. But, although it may be changed in form as much and as often as we please, and although such changes are going on without ceasing all around us, yet no portion of energy is ever lost or destroyed. Whenever a given quantity of energy disappears at any place, an exactly equivalent amount appears somewhere at the same instant, either in the same or different forms. Thus, the total quantity of energy in the universe appears to be constant. This law is known as the principle of Conservation of Energy. We must remember, then, that nothing but energy can be the cause of energy ; and that, if energy disappears in a given place, an equivalent amount must somewhere be produced. We can change the place or form of energy, but we can neither create nor destroy it any more than we can create or destroy matter. In familiar language we speak of energy as appearing or disappearing; as being generated, consumed, lost, etc. But this is allowable solely as a matter of convenience. The Law of Conservation of Energy is wholly based upon experiment and measurement, as are all physical laws. We know of no exception to it. The confidence which physicists have in it is so great that it is used as a test to determine whether anything is or is not energy. If the thing in question can be changed into one or more known kinds of energy, or if any known kind of energy can be transformed into it, then it is believed to be energy. Instances of Transformation of Energy and examples of various forms will now be given. Many more will come up incidentally as we go on. It is not possible at this stage of advancement for the pupil to measure the quantities of energy transformed ; the mere fact of transformation alone will be shown : Eub the fingers briskly to and fro upon any surface, say of cloth or wood, and you will feel a sensation of warmth, due, of course, to heat. You have expended muscular energy in moving the hand backward and forward against the resistance of friction, and heat has been produced. The more the muscular energy expended, the greater the amount of heat generated. The muscular energy is changed into the form of energy which we call heat (page 37). Rub briskly over a cloth or wooden surface a smooth light piece of metal, such as a button or a thin key. It will soon become warm, and even quite hot to the touch. Here, again, muscular energy has been transformed into heat energy. Place a lump of lead upon an anvil. Strike it a blow with a heavy hammer. The lump will be crushed out of shape, and you will find, on picking it up, that it is quite warm. At the instant before striking, the hammer, owing to its mass and velocity, possessed energy of onward motion imparted by the person and by gravity. On striking the AVAILABILITY OF ENERGY. 41 lead the hammer is brought nearly to rest, and therefore loses nearly all this energy. The equivalent of most of this energy appears in the form of heat in the lead. Here, then, energy of onward motion is converted into heat. Not all the energy is thus transformed, however, for part remains in the rebounding hammer, and part is transferred to the anvil, setting it into slight motion. The hammer and the anvil are also set into sound vibration, some of the energy being thus changed into that form of energy. Availability of Energy. — When energy is transformed, it usually happens that not all the energy of the given form can be changed into the desired form, but that some part (usually a considerable part) is incidentally and unavoidably changed into other forms which are not desired and are of no use to us. This follows from certain laws of energy which can not be here considered, and which lead us to regard some forms of energy as of a higher grade than others. The quantity of energy thus changed into forms not desired and not available for our purposes at the time, is often spoken of as wasted or lost ; but you will see that it is still energy, and is only wasted or lost in the sense of not being available for the purpose in hand. occasion great inconvenience. A saw used to cut wood or metal becomes warm or even hot ; a drill or gimlet is heated as the hole is bored ; a file " heats " when in operation on a piece of metal ; a car-wheel grows hot when the brakes are applied. The saw and drill are sometimes oiled in order to reduce the friction and thus lessen the work done in turning them ; the heat produced is, of course, diminished in the same proportion. A shaft, journal, or axle of any kind, if not properly oiled to reduce friction, would heat very much in its bearings, causing the destruction or injury of the bearing, or at least making it impossible to turn the shaft. Instances of this are to be seen in a " set " wagon-wheel and the " hot box" on the railroad train. In all these cases the heat is a serious cause of inconvenience. It is here a kind of energy which is not wanted, and its production causes a waste of the energy of the operator or the machinery. Potential Energy. — Bodies are frequently so situated with respect to some kind of energy — for example, that causing gravitation or electrical and magnetic effects — that if left free to move they will themselves acquire energy. In such instances, the body does not possess actual energy, but only the possibility of acquiring it. It is said to possess potential or possible energy. Thus any object anywhere above the earth's surface, whether moving in any direction or at rest, is said to possess potential energy with reference to the surface. This, however, is not energy actually possessed by the object, but is merely a convenient phrase to denote the energy which the object can acquire by moving from its given position to the surface of the earth. A piece of iron at a distance from a magnet possesses potential energy with reference to the magnet, because, if allowed to move, it will acquire actual energy in moving toward the magnet. Work further defined. — In all these illustrations of the change of place or form of energy, the process of transference or of transformation is called Work. Thus, when A accelerates B (page 31), we say that A does work on B. When we rub the metal and produce heat (page 40), we do work ; when the hammer strikes the piece of lead (page 40), it performs work upon the lead. Every such case has been shown to be merely a change in place or form of energy. We may therefore conclude that What have you learned in regard to the indestructibility of matter ? Explain fully what is meant by the transformation and conservation of energy. If energy disappears, what are we to infer ? Are there exceptions to the Law of Conservation of Energy ? Give instances of the transformation of energy, repeating those explained in the book, and drawing upon your own experience. A bullet or cannon-ball striking a target or armor becomes heated. A large part of its energy is converted into heat-energy hi itself and in the object penetrated and crushed. Suppose all its energy were to be converted into heat at the blow, how hot would the ball be ? Meteorites, or shooting-stars, are masses of material which enter our atmosphere from space and fall by their weight toward the earth They enter with, or acquire, a very great velocity While moving through the air with this speed, they experience resistance, in overcoming which, heat is produced in sufficient amount to raise them to the red or white heat that renders them visible. What kinds of energy are here transformed, and how ? Imagine yourself on an observation-car traveling at a high rate of speed. If you should throw a ball vertically upward, what would be the appearance of its path to an observer not on the train ? Draw a diagram showing its actual path. Tendency to Acceleration.— When the ball A of experiment on page 31 strikes B and accelerates it, the action is not instantaneous, but merely of very brief duration. Time is required to accelerate any mass of matter, however small. During this time of action, the velocity of B is gradually increased by the action of the energy of A ; and we may say that, while the action is going on, B has a tendency to acceleration with respect to A. By this we mean that B will be accelerated, unless some resistance is offered. 44 FORCE. unless some resistance acts to prevent. It mil therefore be understood that the tendency is spoken of as existing, whether the acceleration occurs or not. It is clear in this case that the tendency to acceleration is due to the action of the energy of A upon B. As there is reason to believe that acceleration can never be produced by anything but energy, so tendency to acceleration must always be due to the action of energy. In this experiment the duration of the contact between A and B, and therefore of the tendency to acceleration, was very brief. But we have many examples of continuous tendencies. For instance, any object tends to fall (with acceleration) toward the earth. This tendency is continuous. A piece of iron near a magnet tends continuously to approach the magnet. Force. — This action by which some forms of energy sometimes produce in bodies a tendency to acceleration is called Force. We may then define force as being that action of energy by which it produces a tendency to acceleration. It is therefore merely an action of energy upon bodies. FAMILIAR EXAMPLES OF TENDENCY TO ACCELERATION, OR FORCE. — Hold this book, or any object, in your hand, just above the table. It falls downward until it reaches the table, or some other object which interrupts its motion. Here, then, is a tendency to acceleration — and thus, a force. This force we call Weight. Tear off some bits of newspaper not larger than the letters of this book. Take your eraser, or, better, a piece of vulcanite, such as a hard rubber comb, or a fountain or stylographic pen. Rub it once slowly over your hand. Bring it just over the bits of paper. They do not move. Wipe the vulcanite dry, then rub it briskly for a few seconds upon any dry woolen, silk, or fur, and immediately bring it again over the bits. They fly up, and perhaps stick to it. Here is tendency to motion, or force, due to another cause, Electrification. In many instances a sensation of push or pull enables us to recognize the presence of a force, as when we are holding an object in the hand. It may aid us if we think of force as a push or pull (due to energy of some kind), but we must not regard this as a definition of force. NATURE AND ACTION OP FORCE. 45 Action of Force. — In speaking of acceleration or other effects, such as compression, bending, stretch, etc., we should speak of them as due to the action of energy, for only energy can produce them. But it is often more convenient to speak of them as due to the action of the force instead of to that of the energy which causes the force. A force, it will be seen, can have no capacity to do work; such capacity is energy. It is of very great importance that this fact should be borne in mind whenever work or anything else is spoken of as due to the action of force. Line of Action of a Force. — The direction in which the body tends to be accelerated is called the direction of the force. The particular line along which a particle or body tends to be accelerated is called the line of action of the force. shall find, as we go on, that whenever any body or particle has a tendency to acceleration, we have reason to believe that there is somewhere another body or particle which tends to be accelerated toward or away from the first at the same time. The tendency to acceleration never belongs to a single body only, or to a single particle of matter, but is always a tendency of two or more bodies or particles to approach, or recede from, one another with an accelerated motion. Objects tend to fall toward the earth, but the earth at the same time tends to fall toward the objects. The paper bits and the rubbed body tend to approach each other. Recognition of the Presence of a Force. — We have just shown that a tendency to acceleration may exist when there is no acceleration, as well as when there is. It is essential that we should know how to recognize the presence of a force in all cases. There are two methods : 2. By showing that there is a counterbalancing force. The first method detects and studies any unbalanced force — i. e., one acting on a body free to move. The second detects as far as possible any balanced force — i. e., one acting where the body is not entirely free to move. As balanced and unbalanced forces often exist together, both methods must be applied in all cases. Force recognized by Acceleration. — If a free body is acted upon by force, its motion will be accelerated or retarded as long as the force continues. Hence, if a free body shows acceleration, we know that a force must be present (that is, that energy must be acting on the body) ; and so long as the acceleration continues, we know that the force is operating. Let us examine the case of a freely falling body, and see how we recognize the presence of the force which we call its weight. Ask some one to drop a good-sized white stone or ball from a high window, signaling to you the exact instant of dropping it, while you stand at some distance and watch its fall. Have the experiment repeated, until you become accustomed to the motion of the object, so that you can observe it well. You will soon see that the motion is accelerated. The ball at the start moves very slowly (you must observe closely to see this), but rapidly gains speed, and during the latter part of the fall moves so fast that you can hardly follow it with your eye. Thus, the motion is accelerated, not only at the start, but throughout the fall. Hence there must have been a force (and therefore energy) acting throughout the fall Moreover, as the ball started from a condition of rest, without effort of the person holding it, and as it will start at any desired instant, there must be a force acting always upon it. As the experiment will succeed at all times, in all places, and with all objects except feathers, etc., whose motion is prevented by buoyancy or other known causes, we may generalize, and say that all objects near the earth appear to be always acted upon by a force (caused by energy of some kind) drawing them toward the earth. This force is what we call Weight. As before stated, it is a force acting between the earth and the object — i. e., tending to make the earth and the object approach each other. BALANCED FORCES. 47 Weight is, therefore, a force which acts always on all objects near the earth. That everything has weight, is one of the most familiar facts of our common knowledge. Forces recognized by means of a Counterbalancing Force. — We naturally ask whether there are not some means of recognizing the existence of a force without allowing acceleration to occur. The answer is that there are. To show what the means are, we have first to show that forces can be balanced or neutralized by, and only by, other forces. Balanced Forces. — If two equal and opposite forces be simultaneously applied to a free body, its motion will be unchanged. Two such forces are called balanced forces. This may be illustrated by the following experiment : Over a pulley, P, moving with little friction (a round stick, such as a broom-handle or even a lead-pencil, will .answer very well), hang two bodies, A and B, of equal weight, and connected by a cord. Neither will rise or fall. But A, for example, is pulled downward by a force (its weight). Why is it not accelerated f B by its weight pulls downward on the part of the cord at D. This portion of the cord pulls on the part next beyond, and this in turn on the next section, and so on around to C, where the cord pulls upward on A by the same amount (neglecting friction) that B pulls downward. But B pulls with an amount equal to its weight, and this is equal to the weight of A. Hence, A is pulled upward with a force just equal to its weight, and exactly opposite in direction. The acceleration of A which would have been produced by its weight is thus prevented by the application of an equal and opposite force. The upward pull on A by the string, and the weight of A, are then two balanced forces. The same statement is true of B. The balanced forces, therefore, can not start the bodies. If you push up on A or B, the whole system will be set in motion. When you stop pushing, all acceleration will cease, and the motion would continue uniform, if it were not for friction, showing that the balanced forces can not change the speed of the bodies when moving. started upward — that is, in the direction of the unbalanced portion of the force. Similarly, if the weight B be made smaller than A, the excess of force will be in the opposite direction, and A will move down. In each case the force has, of course, to accelerate both A and B, and both move in the direction of the greatest force upon them. From these and similar experiments we may conclude that, to prevent acceleration in a body which is acted upon by a force, there must be applied an equal force in an exactly opposite direction. Suppose, therefore, we find at any time a body which we know is acted upon by a force, and which is not being accelerated. Then we know that the body is also being acted upon by a force equal and opposite to the first. Even if the body is being accelerated, the acceleration may be due to some unbalanced part of all the forces acting upon it, and may not be the result of a single force only. This affords us a means of recognizing the existence of forces, without allowing the acceleration to be produced. Anything which can be balanced against any known force must itself be a force. We have one convenient recognized force to begin with, viz., Weight. QUESTIONS.— What is meant by tendency to acceleration ? To what must such a tendency always be due ? Give an example of a brief tendency to acceleration. Of a continuous one. Can a tendency continue after the energy causing it has ceased to act ? What is denoted by the term Force ? Define force. To what is force always due ? Can there be any force where there is no energy ? What is the sole cause of force ? Can force exist by itself ? Are force and energy the same thing ? Would it ever be correct to use one term for the other ? Why do we speak of the effects of energy upon bodies as the effects of the force (i. e., the tendency to acceleration) which the energy produces ? Is force ever the real cause of any effect ? Why not ? What is the cause ? What do we mean by the term line of action of a force ? What is the direction of the line of action of weight ? Give some examples of forces. Is it found that a force ever acts on only a single particle of matter ? In what two ways may we recognize the presence of a force ? Protfe that weight is always acting upon any object near the earth. What is weight ? Is it energy ? Is it due to energy ? To what particular kind of energy is it due ? If we see a body moving with retarded motion, how do we know that it is being acted upon by a force ? Why do we speak of the same case of acceleration sometimes as due to force, sometimes as due to energy, and yet say that energy and force are not the same thing ? EXAMPLES OF FORCES. What is meant by balanced forces ? Give an illustration of two forces balancing each other ? How can we prevent the acceleration of a body acted upon by a force ? Is there any other way ? If we find a body which we know to be acted upon by a force, but which is not moving, what inference do we draw ? How does this enable us to recognize other forces ? Elasticity. — When objects are stretched, compressed, bent, or twisted, they tend, as a rule, to spring back to their original or normal size and shape. A continuous force is necessary to prevent their doing so. If the objects are stretched or compressed too much, they take up permanently a stretched, compressed, or bent shape ; but with this permanent change we are not at present concerned. The property of tending to resume the normal size or shape is called Elasticity. It is due to forces which" are brought into action by the change in size or form. These are known as elastic forces, or forces of elasticity. when under stretch. Fasten a rubber band to a nail or hook in the wall. Attach to the lower end of the band a stone or any convenient object (Fig. 13). What occurs? The band stretches by a certain amount, and then, if strong enough not to break, stops, holding the body up from falling. Mark two points on the band with a piece of chalk, one near each end, and measure their distance apart when the. object is hanging on the band. Take off the object and hang it on again. Measure once more the distance of the points apart. Try the experiment on another day, in another place, and under a variety of conditions. You will find that the band is always stretched equally by the same object. If you use a lighter object, the stretch will be less; if a heavier one, it will be greater. The Object hung on the Band has Weight, which is prevented from producing acceleration after the band has stretched to a certain amount. The weight must, therefore, be counterbalanced by an equal and opposite force. The rubber band must pull upward just as strongly as the object pulls downward. The particles of the rubber, when stretched from their original positions, show a tendency to return. This force is greater the more the band is stretched, and is zero when the band is not stretched at all. It is therefore a force which is called into action more and more strongly as the particles of the rubber are pulled farther apart, and it is due to the elasticity of stretch. It is exhibited by all solids, and to some extent by liquids. Instead of a rubber band, use a spiral spring. It will be stretched in a similar way ; but this is really a case of combined bending and twisting. Or use a string, a straight wire, a glass rod, or a piece of any solid substance, either large or small. It will be stretched just as the band was ; but you will not easily discover the fact, for the stretch will be so small that it can not easily be appreciated. With proper apparatus, however, it can be seen and even measured. when compressed. Place a thick piece of rubber on the table. Lay a heavy object on the rubber. Notice that the thickness of the rubber is made less. If in place of the rubber we were to use any other object strong enough not to break, it would be similarly in a state of compression and would be exerting a force due to elasticity when the object rested upon it. The compression can sometimes be seen, as in the case of rubber, but is often so slight as to require delicate apparatus to measure it. As the acceleration which the weight would produce is prevented, the compressed solid must be exerting a force equal and opposite to the weight of the object. The particles of the rubber are brought nearer together and show a tendency to move back to their original positions. This tendency constitutes the force of elasticity of compression, hibited. Fasten one end of a long, slender rod of wood (about a yard in length and half an inch on a side) to a table by means of a clamp or nails. Hang a heavy object on the end. This end will move downward to a certain point, and after a few vibrations will come to rest there. The rod will be bent into a curved form. In this condition the upper layers of the wood (convex side) are in a condition of stretch ; the lower layers (concave side) are in compression. You can illustrate this by bending a twig in your hand and examining the appearance of the upper and lower sides as you bend it. The elastic forces called into play in bending are those of compression and stretch. is twisted, it exhibits a force due to Elasticity of Torsion. Take hold of the end of the wooden rod of the last experiment, after removing the weight. Twist the rod without bending it. The more you twist it, the greater force you have to exert. When you let go your hold, the wood untwists. The operation of twisting changes the relative positions of the particles, which, when thus treated, show a tendency to return to their original positions. This is another exhibition of elastic force, and is called elasticity of torsion. All Elasticity is of the Same Kind, although appearing in somewhat different ways. It is doubtless due to some form of energy which gives the molecules a tendency to move toward one another when they are separated, or away from one another when they are crowded together by this form of energy is, nothing is known. In the examples of elasticity, the force applied to produce the stretch, compression, etc., was the weight of some object. That force was used merely for convenience ; any other might have been employed. For instance, we might hang on the rubber band a piece of iron ; the band will be stretched to hold the weight of the iron. If the magnet be now brought up beneath the iron, the band will be further stretched by the action of magnetic force between the iron and the magnet. We must remember also that the band when hanging is somewhat stretched by its own weight alone ; similarly, the block of rubber is compressed and the wooden rod bent slightly by their own weights. From these experiments, and others of the same nature, it follows that whenever we see any object under Stretch, Compression, Bending, or Twisting, we may be sure that a force due to elasticity is being exerted. Thus we have added these to our list of recognized forces, and can use them in turn as a means of recognizing others. Think out for yourself how the table is compressed when an object is laid upon it ; how the hook is bent upon which the rubber band is hung; how the floor bends when you walk over it; how a bridge yields when a heavy load crosses it, as also under its own weight ; and any other cases of stretching, compression, bending, and torsion, which may occur to- you. Try in each of them to recognize the fact that an elastic force is being exerted. Forces occur under various conditions of matter. They are not indestructible in the sense that matter and energy are, but may be made larger or smaller in amount or in many cases annihilated altogether. Always remember that force is merely a condition oi matter which is due to the action of energy. When we find a force, we at once inquire what the energy causing the force is. This question we can answer definitely in a few cases only. In most instances, our knowledge of the exact nature of the motion causing different forms of energy is very incomplete. A few other examples of forces will now be least two bodies are concerned in every force. Electric Attraction and Repulsion. — Suspend two pith-balls from glass rods or tubes mounted in wooden blocks, as shown in Fig. 15, using very fine silk thread (undyed floss or cocoon-fiber is best). will then hang straight down as at a and b, with the threads vertical. There is no electric force between them ; they do not tend to approach, or recede from, each other. shows that there is a tendency for a and b to be accelerated toward each other — that is, that there is a force of attraction between them. The ball a was the one electrified ; but the force due to its electrified condition is not simply a tendency of a to move toward J, or of b to move toward a, but it is a tendency of both a and b mutually to approach each other. Next roll each of the balls in the fingers for a moment ; they will then hang in their original vertical positions without attraction or repulsion. Thus we have been able to produce force and to destroy it Electrify both balls by touching them with the rubbed vulcanite, and bring them toward each other. They will now tend to move apart and will hang in the positions e and /, showing that there is a repulsive force between them. Other interesting experiments with the pith-balls will be suggested when the subject of electricity is reached. Magnetic Attraction. — Provide yourself with a magnet and a nail. Bring the nail and one end of the magnet gradually toward each other. When they are near together, you will feel that they tend to approach ; you will have to hold each back, or they will rush together. There is, then, a force of attraction between them, and this force is greater the nearer they come together, being imperceptible at a distance of a few inches. It is called magnetic force or magnetic attraction, and is due to magnetism. The Earth tends to approach a Body as well as a body the earth. We can not readily show this by the method of watching their motions; but we are very well assured of the fact by other knowledge which we possess regarding similar actions. We know that the moon revolves around the earth, that the earth and other planets revolve around the sun, that some stars form pairs revolving about each other. For certain reasons we believe that every particle of matter tends to approach every other particle, the amount of the tendency depending on the mass of the two particles and their distance apart. This, when fully stated, is called the Law of Gravitation. Starting from this assumption, we must believe that the earth, moon, sun, and all the planets, attract one another with amounts depending on their masses and their distances apart at any given instant. If there were only one planet, it would move about the sun in a perfectly regular path. If there were two revolving at different distances and in different times, then their motion would not be perfectly regular, but when they were near together each would disturb the position of the other, now slowing, now increasing, its speed, and also moving it more or less aside from its simple path. DIRECTION CHANGED BY FORCE. must be very complicated. Their paths are disturbed by their mutual actions, and the orbit of our moon is particularly so. Yet astronomers, basing their work wholly on the law of gravitation, are able to compute the position of the moon for any given time several years in the future. We therefore have here a remarkable piece of evidence that the assumption of the law of gravitation is correct; and this assumption involves the idea that at least two bodies are necessary to produce this kind of tendency to motion, and that each of the bodies concerned has an equal tendency to move toward the other. FORCE CHANGING DIRECTION OF MOTION. Effect of Force inclined to Direction of MovingBody. — In the cases of balanced forces, the lines of action of the forces have been in opposite directions. Let us see the effect of force inclined to the direction of a body's motion. Throw a ball in any other direction than a vertical one. It will move in a curved line. Suppose the ball to start at A and to be thrown in the direction of A F. It would move along this straight line A F at a uniform rate if there were C, no tendency (weight) to fall zontally, it would have moved in the path A b c e of Fig. 17. If thrown obliquely downward in the direction A E, Fig. 17, it would have moved in the path A B' C' D'. In all cases, the motion is in a curved path. Notice that the direction of action of the weight, being vertically downward, is always inclined to the path, while in the case of a body moving verti- is continually changed. It will also be seen by inspection that the motion in the three cases above is accelerated or retarded as well as curved; but if the force is exactly and always at right angles to the path, the velocity is uniform, although the direction is continually changing. This is the case of a body revolving uniformly in a circle. It may be illustrated by whirling around a FIG. 17. stone on the end of a string. QUESTIONS.— What is elasticity ? What are the forces of elasticity ? Show that a stretched object exerts a force tending to restore it to its normal size and shape. If a weight is hung on any object whatever, is the object stretched ? Is it exerting a force ? Answer similar questions for compression, bending, and twisting. What is the particular form of energy causing the elastic forces ? As you stand upon the floor, does the floor exert an upward force against your feet ? How much force does it exert ? To what property of the floor is the force due ? Does the floor push upward against the table standing upon it ? Why is not the table moved upward by this push ? Does a mountain press upon the earth beneath it ? If the upper layers of the earth press upon those beneath, what must be the amount of pressure upon layers several miles below the surface ? When a train passes on a bridge, how much does it press upon the bridge ? Can the bridge be prevented from bending slightly ? How does the bridge balance the weight of the train ? Does one attract more than the other ? How can you prove that the attraction between a magnet and iron is mutual ? When an object falls, does the earth move upward toward it ? Describe by diagram the experiment showing that force changes the direction of motion of a body. Acceleration and the Tendency to Acceleration, it must be remembered, are caused by the action of energy, and can result from nothing else. This action of energy has already been called Force. In order that you may better PRODUCTION OF FORCE. 57 understand how it is possible for energy to produce force, and why we believe that force is wholly due to energy, consider carefully the following illustration : Hold a bat or a board in your hands and let some one throw against it an elastic ball. To prevent the board from moving when the ball strikes it, you will have to push against it. The ball exerts a force during impact. You will then have to exert a continuous push to hold the board steady. If the board is held in place by springs, these springs will be compressed until the pressure which they exert, owing to elasticity, will be just equal to the pressure or force caused by the striking balls. The compression will be kept up as long as the bombardment of balls continues. It is thus clear that a continuous bombardment of balls can produce a sensibly continuous force. when they are producing force : First, when the board is stationary. If we had suitable means of measuring, we should find (provided board and balls were perfectly elastic) that the balls rebound with just the velocity, and therefore just the energy, with which they strike. They therefore lose no energy when producing force if the body acted upon is stationary. The mere production of force does not require the expenditure of energy. The only change made is in the direction of motion of the balls. Again, if we could measure, we should find that when the board is moving in the direction in which the balls tend to make it move, they will rebound with less velocity than that with which they strike, and therefore with less energy. They are thus giving up energy to the board, which, if free to move, will be accelerated just as was the ball B (page 31). The acceleration of the board will be such that it will gain energy at just the rate at which the striking balls lose it. The energy expended by the balls is simply transferred or given up to the board. The force exists as before, but no energy is expended in maintaining it. Thirdly, when the board is pushed back against the balls. Here the same amount of force exists as in both the other cases; but now each striking ball rebounds with greater velocity than that with which it strikes, and therefore gains energy. To push the board back will require an application of energy, which is transferred to the system of balls in the shape of increased energy of motion. Fourthly, where the board is allowed to be moved back by the balls with a uniform motion. In this case the force will be present as before. The balls will also rebound with less than their striking velocity, and will therefore give up energy to (i. e., do work upon) the board ; but as the board is moving with a uniform velocity, it is not accumulating energy as in the second case. The energy here can simply be transmitted through the board to some other object. In all these cases, if we had merely seen the compression of the springs or felt that we were obliged to push, and had been ignorant or unconscious of the energy on the other side of the board, we should have been aware only of a condition which we have already recognized in other cases as due to force. We should naturally, therefore, have spoken of the force as causing the acceleration, doing the work, and being worked against ; but it is evident that such a statement would have been imperfect. This illustrates the position we are in respecting weight, elasticity, etc. We perceive the force by methods already given, but are ignorant of the exact nature of its cause. We speak of weight and other forces as doing work, while the real agent is energy of some kind which is causing the force in question. The illustration just given is a purely imaginary one, although entirely practicable ; but we have in nature a force which is explained on precisely this principle. It will be shown, when gases are treated, that a gas, for example air, in an inclosed space, exerts an outward pressure upon all the inclosing walls. This pressure is explained as being due to the bombardment of the walls by the molecules of the gas in their violent to-and-fro motions described on page 37. force, therefore all force is produced by just such a process. It is probable that this is not true, but that the form of the energy causing such forces as weight, elasticity, magnetic and electrical attraction, etc., is or may be very different from a process of bombardment. The argument from which results the belief that force is always caused by energy is — first, that it is strictly in accordance with the principle of the conservation of energy (page 39) ; second, that it leads us into no contradiction with observed facts of any kind, but, on the contrary, enables us to explain many facts that can not be so well accounted for in any other way. QUESTIONS.— Define force. On what only does it depend, and in what does it always manifest itself ? Give an illustration showing that energy is the cause of force, and that force is wholly due to energy. Do we understand the source of every manifested force ? Why ? Does the production of force require the expenditure of energy ? In pushing a board back against striking balls, what becomes of the energy applied ? Sum up the four cases in which the energy of striking balls produced force, and explain the transfer of energy in each. In these cases, had we been ignorant of the "energy, to what would we have ascribed the visible effects ? State a parallel case from the properties of gases. Can we assume that all force is similarly caused ? Advance the argument from which results the belief that all force is produced by energy. Throw a ball straight upward. Is its condition the same going up as coming down ? In what respect is there a difference ? Does the same tendency of acceleration toward the earth exist in both cases ? Does the ball weigh the same whether moving upward or downward ? Prop up a smooth board on the floor and lay a marble on the elevated end. Release the marble, and as it rolls down the board what will it show ? Draw chalkmarks across the board at equal intervals, and you will perceive the change of speed more readily. To what is the motion of the ball here due ? Hang up the rubber band as explained. The band will stretch slightly till its elastic force balances the weight of the iron. Now bring your magnet carefully up under it. The band will stretch further, showing a stronger pull by the iron than that due to its weight. If the magnet is brought close enough, the iron will be pulled up into contact with it. Then, if you pull downward, you will find that the band is stretched considerably, and may even break before the iron can be separated from the magnet. Does the rubber exert a counterbalancing force ? How ? they possess certain characteristics called properties. The Essential Properties of Matter. — Some of these properties characterize all objects in common — that is, if any object whatever be examined, it will be found to have NOTE. — In the picture above are represented a number of simple pieces of apparatus, with the help of which, together with such contrivances as may easily be improvised from materials found in every household, the pupil can perform for himself the experiments described in the following sections on the Properties of Matter, Dynamics, Gravitation, and Machines : No. 1 represents a wooden wagon, with pulley and scale-pan ; 2, a grooved board with ivory balls ; 3, a pulley and weights ; 4, a pole with weights supported by spring-balances ; 5, apparatus for equilibrium of moments of forces tending to produce rotation ; 6, a piece of cardboard hanging on a pin, with plumb-line in front, for finding center of gravity ; 7, a block of wood, with string attached to slide on board, for illustrating the laws of friction ; 8, a balance ; 9, pendulums ; 10, pulleys of different varie.ties. This apparatus may be largely constructed by any ingenious pupil who can handle carpenter's tools, or the outfit may be obtained from any reputable dealer in optical and philosophical instruments. MASS AND EXTENSION. 61 them. Moreover, in whatever way it is treated, whether it is chemically separated into its constituents or combined into other compounds, the resulting substances will still show these properties. So far as we can perceive, they belong to any portion of matter, however small, even to a single atom. Thus they appear to be properties of the matter of which objects are made up, and, as far as human knowledge extends, there is no form of matter which does not possess them. These essential properties are Mass, Extension, Impenetrability, Indestructibility, and Inertia. There are certain other properties which appear to belong to bodies (collections of atoms), but not to be essential to matter itself, and therefore not to characterize single atoms. Some of these Properties of Bodies, such as Density, Divisibility, and Porosity, are merely facts or hypotheses concerning the structure of bodies. Others, like Hardness, Ductility, Transparency, Electric Conductivity, relate to the qualities which the bodies show when treated in certain ways. Still others, like Gravitation, Cohesion, Elasticity, etc., are conditions of matter due to the action of energy. It is useless to attempt to enumerate all these properties of bodies ; they will be considered one by one as the study of the subject progresses. Mass. — If you were to ask how much of a certain material substance existed, and the reply were made none, you would, of course, understand that the substance did not exist. By the question " how much," you mean what quantity. The property of having quantity is therefore essential to matter ; but the term mass stands simply for quantity of matter (page 11). So we may say that mass is an essential property of matter. Extension is the property of occupying space, or, in other words, of having volume (length, breadth, and thickness). "We recognize easily that almost every material object has length, breadth, and thickness, and thus occupies or fills up more or less completely a portion of space. Some objects are so small that we can not see them with the unaided eye ; but it is impossible to think of them as not hav- 62 PROPERTIES AND CONSTITUTION OF MATTER. ing volume. So accustomed are we to this idea, that, if any one were to say that a body occupied no space, we should declare at once that it did not exist. Many things which are too small for us to appreciate with the eye can be seen with a magnifier. We have reason to believe that there are other objects too small to be seen even with the most powerful microscope, yet we realize that they occupy a minute portion of space. We know that some things are so thin that they seem to have no sensible thickness ; but if we imagine many hundreds or thousands of them piled together, we may be sure that they will have a perceptible thickness. Thus, gold-leaf is so thin as to appear of no sensible thickness to the touch ; but if several hundred thousand sheets of it were piled one upon another, the whole would have a thickness of an inch or more This shows that each sheet has thickness. The idea of occupying space is thus one which is inseparably associated with our idea of matter. We can not conceive of any portion of matter, however minute, which would not have some volume. Impenetrability. — We have seen that matter occupies space. We also believe that no two atoms of matter can occupy the same portion of space at the same time. It has been further shown that the molecules or atoms of matter are probably never packed solidly together, but, on the other hand, have always spaces between them. When we say, then, that no two atoms can occupy the same space at the same time, we do not mean to apply the statement to material objects or bodies composed of many atoms. The atoms of two bodies can not occupy the same actual portion of space ; but the atoms of one body may lie in the spaces between the atoms of the other, so that two bodies may have just the same apparent volume as one. This will be more fully explained in the section on Porosity. To illustrate impenetrability, take any object, such as a stone or a piece of wood. Varnish it, if necessary, to keep water from entering its cavities ; immerse it in a tumbler full of water. The water will overflow, being displaced by the object. The volume of the displaced water will be exactly equal to that of the immersed solid. Invert a tumbler ; force it mouth downward into a dish of water. The water does not enter, because of the air in the tumbler. The air acts as a solid, except that it is somewhat compressed by the water pressure, as you will see on examination. These experiments illustrate the familiar statement that two bodies " can not occupy the same space at the same time." But the true idea of impenetrability has reference to the atoms of matter rather than to bodies. fact that matter is indestructible can not easily be proved at this stage of our studies. The assertion must be accepted as true, although seemingly contrary to experience. Stand a tumbler of water on the table and leave it for a day or two. The water disappears gradually, and you can not see what has become of it. It appears to have been destroyed ; but it has only passed off into the air in the form of invisible vapor The vapor is still the same substance as the water ; the molecules of the water vapor and of the liquid water are exactly the same. The difference between the vapor and liquid is only that the molecules in the vapor are very much farther apart than in the liquid (a cubic inch of the liquid water making over 60,000 cubic inches of vapor at the ordinary room temperature). Thus the vapor can not be distinguished by the eye from the air of the room. Now, how can we tell that the water still exists in the air ? Take a tumbler of ice-water, or, better, a piece of glass, a spoon, or any object which has been lying in some very cold place. Wipe it dry on the outside without warming it, and hold it just above the water in the tumbler. There will very quickly appear on its surface a coating of fine particles or drops which you will recognize as water. The cold surface has collected the molecules of water from the air into the liquid form, or, as we say, has condensed the vapor. You see every day a layer of moisture on the pitcher of ice- water, or on the cold window-pane a coating of dew or frost. This is water or ice, produced by condensing from the air of the room the moisture or water vapor which has evaporated from the surface of water in the room or elsewhere. When water disappears in this way, then, it is not destroyed, but merely changed into a different condition, in which we do not happen to be able to perceive it so readily. The same change takes place when water boils away, when clothes dry, when ice and snow evaporate. The vapor is often condensed in the air itself, and we see what we call rain, clouds, mist, and fog. These are all made up of particles vapor as it is chilled by some process which happens to cool the air. Another way in which matter appears to be destroyed, but is not, may be studied in the chemical changes that take place in combustion or burning. Wood or coal when set on fire continues to burn until nothing is left but ashes. A pile of wood will leave an amount of ash so small that you can lift it with hardly a thought that it has any weight. The ashes then retain only a small part of the matter which made up the wood. Where has the rest of it gone ? Has it been destroyed ? In one sense it has, for it no longer exists as wood. A building burned to the ground is destroyed as far as its usefulness as a building is concerned. But in neither case has the matter contained in the object been destroyed. There is just as much matter as before, but its/orm has been changed. The wood has been converted partly into water vapor, partly into invisible gases, and partly into ash. If we should measure the mass of the wood with which we start, and then could collect all these various substances formed by the burning and in any way measure their mass, we should find that this is considerably greater than the mass of wood. Thus we have not only as much matter as in the wood with which we started, but in reality more, because some oxygen gas from the air combined with the wood as it burned. If the mass of oxygen used were also measured, we should find the sum of this and of the original mass of the wood to be just equal to the mass of the substances collected after the combustion. It would thus have been proved that the mass (amount of matter) is absolutely unchanged, although the form is very different. Many experiments of this sort have been made ; but the most conclusive proof of the indestructibility of matter is to be found in the fact that all over the world chemists, physicists, and artisans, are working upon processes which would surely fail if matter were not indestructible. The fact that matter may change in form in an endless variety of ways, but that the total amount of matter does not change, is sometimes called the principle of the Conservation of Matter. INERTIA. 65 Inertia has already been somewhat discussed (pages 30 to 32). We may explain it by saying that a particle of matter possesses absolutely no power to change its velocity or direction of motion. If the velocity and direction of motion of any material particle or body does change, it is because of the action of energy upon it. The general law which expresses the property of inertia is Newton's first law of motion (see page 31). This law is based wholly on experiment ; but we find very conclusive evidence for it also when we consider what would happen if a body had power to move itself. Such power would involve a suspension of the laws of energy, if not an annihilation of energy itself. Start a ball rolling (without any twist or spin) along a level floor, or, better still, on smooth ice, and watch its motion. Notice first that it moves in a straight line. Unless it meets with obstacles, it does not move upward, or sidewise, or backward. To think of it as jumping upward, or stopping of itself and moving backward, strikes you as absurd — which is only a proof of the uniformity of your experience to the contrary. The ball can not move downward, because of the floor or ice ; we know that its tendency to move downward is not due to itself, but is owing to an action in which the earth is concerned, and that the floor merely counterbalances this action. The floor does not in any way alter the motion of the ball. If the earth were not present, there would be no need of the floor. The ball, then, moves onward in the direction in which it started, merely because nothing acts to change that direction. It does not of itself tend to change the direction of its own motion. This is one evidence that it is inert. Notice next that the ball keeps on moving over a long distance ; and that the smoother the surface upon which it rolls, the farther it will move when started with the same speed. Now we know that there are two actions which tend to stop it. These are the resistance of friction against the floor and the resistance of the air. We can diminish the first by experimenting on a smoother surface, and make the second less effective by using larger and larger balls. "We find as we do so that the distance the ball will go increases, and we may therefore infer that if we could entirely remove these resistances the ball would continue to move at the speed with which it started, and that it would move with uniform velocity. The ball does not, therefore, of itself tend to change its speed. This is a second evidence that it is inert. does not continue to move in a straight line and with the speed of starting, but falls in a curve toward the earth and slows up in speed. Now, we find by experiment that it falls toward the earth just as fast as it would if dropped from the hand and not thrown horizontally. Hence its curved motion is wholly due to its falling toward the earth, and this is caused by the energy of gravitation, and is therefore not due to the body itself alone. Its slowing up in speed is caused by the resistance of the air. Hence we infer that, if these two actions in which outside bodies share should be removed, the ball would go on in a straight line with its original velocity. Select for yourself and study out other examples. Inertia may be further illustrated by piling up half a dozen books with a smooth-covered one at the bottom. Slide them swiftly across the table-top by pushing against the bottom one. Place an obstruction in the way, such as the other hand held firmly down against the table, and let the bottom book strike against it suddenly. What becomes of the top books ? How is this due to inertia ? Passengers often stand in the aisle of a railroad-car as it is approaching the station. When the car stops with some suddenness, they plunge violently forward and sometimes fall. Why? They generally say that they are " thrown " about in such a case. Are they thrown in the sense that a ball is thrown from the hand f A railroad train in motion will not stop until it has expended all its energy of motion in heat and other forms of energy at the brakes, on the rails, in the air, etc. This may be said to be due to its inertia. All these and similar examples should show you how energy depends upon inertia ; but inertia is only the property, and energy is the thing. Neither is due to the other. QUESTIONS.— Name the Essential Properties of matter. Why are they properties of matter rather than of objects ? State some properties that characterize bodies and not the atoms of which they are composed. What is Mass ? Extension ? What is meant by Volume ? The dimensions of a body ? Have microscopic objects length, breadth, and thickness ? Perhaps your teacher or some friend will let you look through a microscope at objects too small to be seen IVISIBILITY. 67 with the unaided eye. Prove that a sheet of gold-leaf has thickness. Define and illustrate Impenetrability. If you fill a tumbler to the brim with water and drop in a bullet, what will take place ? What does this prove ? Show how the atoms of one body may lie in the spaces between the atoms of another body. What do we mean by the Indestructibility of matter ? Illustrate by the evaporation of water from a tumbler ; by the burning of wood. What has become of the matter contained in the objects apparently destroyed ? Take the case of the oil burning in your lamp. Is a particle of its substance lost ? What becomes of the body after death ? State the most conclusive proof that matter is indestructible. What is meant by the Conservation of Matter ? Explain Inertia. If a body had power to move itself, what would be the effect on the laws of energy ? Illustrate inertia by the case of the ball rolling along a smooth floor ; by the case of the ball thrown horizontally ; by the case of the books pushed along the table. Did you ever notice the effect of inertia when a train was entering the depot or a ferry-boat landing in its slip ? Why is it dangerous, when the horses are running, to jump from a carriage ? Because the feet cease to move the instant they strike the ground, while the inertia of the body carries it forward. On what principle is the snow shaken from your arctics by kicking against the door-post ? Can you think of other ways in which \ve avail ourselves of inertia ? CONSTITUTION OF MATTER. Divisibility. — Any object may be cut or broken into pieces and these pieces may be made into others still smaller. This process of mechanical subdivision may be kept up until the substance is reduced to a powder, the limit being apparently only the lack of suitable means of making it finer. By hammering thin sheets of gold repeatedly between sheets of animal membrane, the gold-beater can reduce them to a thickness of only three million ths of an inch. By an ingenious process, a film of gold has been produced of a thickness estimated at one quarter of a millionth of an inch. The average diameter of the water-drops in a cloud causing the halo which you have often seen around the sun or moon is calculated to be one thirteen thousandth of an inch. Such was probably about the size of the dust-particles in the air which produced the remarkable sunset colors so noticeable in 1883-'84 after the Krakatoa eruption. Soap, bubbles, just before breaking, may be as thin as one fortieth of the millionth of an inch ; and it has been computed that a half-pound of spider's web would encircle the earth. All these facts go to show that matter can be divided into parts of extreme smallness or layers of extreme thinness, which is practically the same thing. This property is called Divisibility. But is the divisibility infinite? Can matter be subdivided indefinitely if suitable mechanical means can be provided ? Or should we eventually come to a piece which could not be reduced to any smaller parts ? If the latter be true, then matter is not infinitely divisible, but is " granular " in structure — that is, it is built up of separate individual parts. If matter is perfectly continuous, we can not explain the properties of compressibility and elasticity (see page 50). If it is granular, we can explain these properties, as well as many others, by assuming that the grains or ultimate particles are not in contact throughout the substance, but are separated by intervals. There is a very wide range of chemical as well as physical facts which seem to require the hypothesis that our recognized kinds of matter are built up of parts or units called Atoms, each of which is of fixed mass. Many of these facts require that the atoms should be assumed, not to be in contact with one another, but at a distance apart which is generally greater than their own diameters. They also involve the assumption that these atoms are in to-and-fro motion and in rotation. The facts do not, however, require that the space separating the atoms should be empty, but admit of its being filled with a material offering no resistance to the motion of the atoms through it. A hypothesis has been recently proposed (by Sir William Thomson in 1862) which seems to fulfill these conditions. It assumes that the atoms are rotating rings or vortexes of some given material. You have doubtless seen the rings of smoke sent up from the stack of a locomotive, and have noticed that the smoke composing these rings is always in rotation. If you follow the motion of any individual part of the smoke at a section of the ring, you will see that it moves upward on the inside of the ring, out over the top, down the outside, inward at the bottom, and again upward as before, thus whirling around in a circle in a vertical plane. A ring also frequently rotates as a whole around its axis. It is, moreover, often in vibration. With an apparatus like the one pictured in Pig. 19, you can form and study such rings. Make a box of pasteboard or wood, about 8 inches broad by 8 inches high by 18 inches long, leaving both ends open. Over one end of it stretch loosely a piece of cloth and cover the other end with a cardboard in which is cut a circular hole of four inches or more in diameter. Inside the box place a dish of strong ammonia and another of strong hydrochloric acid, the fumes of which will mix and form within the box a white cloud of smoke consisting of particles of ammonium chloride. Strike the cloth end of the box a tap with the hand. A puff of this smoke will come out at the open end and move slowly onward. Notice that it has the form of a ring whose particles are revolving just as in the smoke-rings from the locomotive. Tap again and send out another, then a third, and so on. By regulating the energy of the blows, you can make the rings move faster or more slowly, and can thus cause them to collide, move through one another, etc. Notice how they rebound on collision with each other, as if elastic, and how they change form on striking solid surfaces. They finally break up and are brought to rest, owing to the friction of the air, for they are really air-rings revolving in air, but made visible by the smoke. Such rings are called vortex-rings. Thomson's hypothesis assumes that atoms are merely such vortexrings existing in a homogeneous continuous material and consisting of it. These atoms are supposed to differ in many respects, especially in size, rate of rotation, and in the kind anjl amount of vibration which they possess, such differences being sufficient to account for the varieties of atoms or of matter which we recognize. The material is of such a nature as to have no friction between its parts, so that the vortex- rings, once started, must continue forever and without change of character. It has been found possible to explain upon this hypothesis some of the fundamental properties and phenomena of matter. Atomic Theory. — Atoms. — We are not obliged, for present purposes, to discuss the questions just suggested. Little is settled in regard to them, and the hypotheses advanced are very incomplete. We will, therefore, concern ourselves only with those few hypotheses which it is convenient to use as we proceed. IV. That atoms are of several kinds, each possessing its own characteristics ; but that the number of kinds is limited, being, as far as is now known, about seventy. to all atoms, and thus to all matter. These assumptions are a somewhat incomplete statement of the hypotheses which form the basis of the so-called " Atomic Theory " of the constitution of matter. The complete theory embraces other hypotheses and offers explanations of many laws and phenomena. There are serious objections to it, and it is to be regarded only as a good working hypothesis on a very difficult subject. Chemical Energy and Affinity. — The atoms of the different kinds of matter (elements) show a tendency to unite with one another and form compound substances. This tendency to combination is stronger between some kinds of atoms than others, and varies with temperature, pressure, and other physical conditions. It follows certain remarkable laws, which are explained in the study of chemistry, and is due to a form of energy called Chemical En- ATOMIC THEORY. 71 ergy, regarding whose exact nature little is known. The forces produced by the action of chemical energy are called chemical forces or, more generally, Chemical Affinity. They are tendencies to acceleration among the atoms. Molecules as distinguished from Atoms. — When, under the influence of chemical energy, the atoms of elements unite to form compounds, they appear to combine only into small groups containing a few atoms each. Such groups constitute Molecules. A molecule, then, is a group of atoms bound together by chemical energy. Thus, a molecule of water consists apparently of two atoms of hydrogen united with one of oxygen. It is evident, therefore, that if the molecules of a compound substance were to be broken up, the character of the compound would disappear. Chemical study leads us to believe, that, with few exceptions, atoms do not exist separately — that is, uncombined with other atoms — even in elementary substances. For instance, when hydrogen gas (an elementary substance) exists uncombined, its molecules are not single atoms, but consist of two atoms united by their chemical energy. We may, therefore, define the Molecule of any substance as the smallest portion of that substance which exists ~by itself, and the Atom as the smallest portion of any element which exists even in combination. Thus any atom is of one kind of matter throughout. The molecule of zinc, cadmium, mercury, and possibly of some few other elements, seems to contain only one atom. The molecule of most elements contains two atoms ; that of phosphorus and of arsenic, four. The molecules of compounds contain different numbers of atoms, according to the complexity of the substances — sometimes as many as several hundred. It is probable that the molecules of gases are separate from one another ; while those of liquids are somewhat tangled together into groups or bunches, and those of solids are crowded still more closely. another, but to be separated by distances which are usually great as compared with the size of the particles themselves. Thus the apparent volume of a body is much larger than that which the molecules or atoms would occupy if packed solidly together. The latter appear to be kept apart, not by reason of any repulsion between them, but because they are in continuous to-and-fro motion. Perhaps you can form an idea of how this can be by imagining a number of boys packed so closely together that there is no room to crowd in another. They would occupy a certain space on the ground. Now, let every boy try to move to and fro, each in a different direction, aiming to move back and forth through just one full step and no more, and let him change the direction at each step. With the exception of those on the edges, the boys will hardly be able to move at first ; but those next the edges will gradually push out their fellows ; these in turn will be pushed out by those farther in, and so on. The result you can easily foresee, and if you try the experiment you will find that the crowd gradually spreads over more space until each boy has the room he needs to move in. The jostling to and fro forces the boys apart and keeps them apart. You can see also that it would continue to keep them apart even if each boy had a slight tendency to move toward the center of the crowd rather than to remain where he was placed. Thus the molecules of a solid substance are held apart from one another merely because they have a to-and-fro motion which they must keep up. The molecules are supposed to be like elastic balls, so that when they strike one another they bound off without loss of energy. Porosity. — Fill a tumbler with shot, as in Fig. 20. Notice that the shot are separated by spaces or interstices ; they do not fill the tumbler full. Imagine the shot to represent the molecules of a substance ; then the spaces represent what are called the pores of the substance, and the property of having these pores is called Porosity. But the shot do not represent these pores properly, for, as just explained, the molecules are supposed not to be in contact as the shot are, but much farther apart. Hence the pores are much larger in proportion to the molecules than the spaces between the shot are in proportion to the shot. Let us examine some proofs that such pores exist. POROSITY. 73 Take a glass tube bent into the form shown in No. 13 of the collection of apparatus on page 173. The short arm of this tube is closed at the top, the long arm is open. Pour a little mercury into the long arm. It will fall to the bottom and inclose above it some air in the short arm. Pour in more mercury, and the volume of this air will be lessened. Pour in additional mercury, and you will find that the air is gradually reduced to smaller and smaller volume. We are then compressing the air — that is, forcing the same mass to occupy less space, or making the air more dense. Now, the only way in which we can picture this action to ourselves, if we regard matter to be impenetrable, seems to be FJG 20._TuMBLER OP SHOT. by imagining the air to consist of particles or molecules with spaces between them, and inferring that when the air is compressed the molecules are simply brought nearer to one another. Solids and liquids are also compressible, but much less so than gases. Compressibility, then, seems to indicate that matter is porous. It has been stated (page 63) that water vapor at ordinary temperatures occupies about 60,000 times as much space as the same mass of liquid water occupies. To understand this we must imagine the water as made up of molecules with spaces between them, which are much larger in the condition of vapor than in that of liquid. Thus the molecules of the vapor appear to be about forty times as far apart on the average as those of the liquid water. Mix thoroughly together two exactly equal volumes of alcohol and water. The mixture might be expected to have just double the volume of either separately — that is, the sum of the separate volumes ; but this will not be the case. The volume of the mixture will be about six per cent less than the sum of the two. This experiment may be made by filling a small flask with water, and then removing exactly one half of the water and replacing it with alcohol. The resulting liquid stands much lower than before in the neck of the flask. There are other liquids which show the same action. minutes, water taken from any part of the tumbler will taste salt. The salt has been dissolved, as we say, by the water. How do we account for this ? We suppose that the salt has become distributed through the pores of the liquid, or that the molecules of salt have passed off into and through the spaces between the molecules of the water and have thus become distributed into all parts of it. Sugar, blue vitriol, and a multitude of familiar solids, thus dissolve in water, as do also gases. The effervescence of soda-water is due to the bubbling out of carbonic-acid gas, which was held in solution under pressure but is given out when the pressure is removed. is less than its original volume plus that of the solid added. Into the tumblerful of shot pour water, or finer shot, or sand, shaking it well. You can thus put a considerably greater mass into the tumbler, which has already as many of the original shot as it can hold. If these shot, instead of being in contact, were in some way held farther apart as the molecules seem to be, you could put still more material into the pores. The shot thus illustrate the porosity of matter, but only in a crude way, for the fact that the molecules are in motion and the shot are at rest makes a great difference in the conditions. Moreover, the molecules should not be imagined to be hard, spherical bodies. They are almost certainly not so, and we have no idea what they are like. Indeed, we can not be too careful to remember that all our notions about molecules are merely hypotheses. Besides the Molecular Pores just described, bodies have cavities of sensible size which are often called pores. Thus, a sponge, a loaf of bread, a brick, wood, the majority of substances, even gold and granite, are full of such holes, and are therefore called porous. This is illustrated in the familiar process of filtering or straining. It is well, therefore, to bear in mind that there are two classes of pores, and to call the molecular spaces molecular pores, or, better, intermolecular (between the molecules). Size of Atoms and Molecules. — There are phenomena which enable physicists to obtain an approximate idea of the number of molecules ordinarily contained in given volumes of certain substances, and even some notion as to the probable size of the molecules themselves. Imagine a SIZE OF ATOMS AND MOLECULES. Y5 cube of water one inch on a side magnified until the length of its side is equal to the diameter of the earth. Then in this enormously magnified cube there would be one molecule to every cubic inch, and of this space the actual molecule itself would probably occupy about one twentieth. Another way of stating the size is to say that if a drop of water were magnified to the size of the earth, the molecules would occupy spaces greater than those filled by small shot, and less than those occupied by base-balls. Of these spaces the molecules would occupy about one twentieth, as before. The smallest object which would fee visible under the most powerful microscope is probably not smaller than a cube of one one hundred-thousandth of an inch on a side. Such a cube would contain from 60,000,000 to 100,000,000 molecules of oxygen or of nitrogen. This would mean twice as many atoms, as each molecule of these gases contains two atoms. Now, as the molecules themselves fill but perhaps one twentieth of this space, it is easy to- understand that a single molecule is much too small to be seen even with the most powerful magnification which we can at present, or perhaps ever, produce. QUESTIONS. — Explain Divisibility. Give some illustrations of the extreme thinness to which layers of certain substances can be reduced ; of the extreme smallness of certain particles in the air. Is matter infinitely divisible ? What do many chemical and physical facts require for their explanation ? What do they involve as regards motion among the atoms ? Are the spaces separating the atoms necessarily empty ? State Thomson's hypothesis. Show how it may be illustrated with vortex-rings. How are the atoms supposed to differ, and to what do these differences give rise ? State the five hypotheses that form the basis of the so-called Atomic Theory. What are elements ? Describe Chemical Energy ; Chemical Affinity. What is chemistry ? Discriminate carefully, with illustrations, between molecules and atoms. Do atoms exist uncombined with other atoms ? How is it in the case of elementary substances ? Instance molecules that contain one atom ; two atoms ; four atoms. Compare the molecules of gases, liquids, and solids, as regards separation. Explain and illustrate the principle on which atoms and molecules are kept apart. What is Porosity ? Can you mention any substance which has visible pores ? Distinguish between these and molecular pores. What is the result of mixing equal volumes of alcohol and water ? Of mixing salt and water ? How does the volume of the liquid of the solution often compare with the original volume plus that of the solid ? [f two volumes of hydrogen were mixed with one of oxygen and exploded, the substance produced would be water. If the explosion were made over mercury in such a way that the water could be collected, it would be found that the amount of water from a litreXsee page 540) of the gases would be but a few 76 MASS, FORCE, ENERGY, AND WORK. drops. How does this illustrate porosity ? How is the foam on a glass of sodawater due to this same property of matter ? How may the mass in a tumbler filled with buckshot be increased ? Why ? What does the familiar process of filtering or straining liquids prove ? Express your idea of the extreme minuteness of molecules and atoms. MASS MEASUREMENT. Equal Masses. — In the arrangement of a system of measurement of mass, force, energy, etc., we must begin with a definition of what constitutes equal masses. Two masses are said to be equal when the same force, acting upon them separately, will produce in them equal accelerations. We have, then, first to show some way by which we can actually measure off equal masses, in accordance with this definition ; secondly, to explain how we can produce graded sets of masses (usually called sets of weights) ; and, thirdly, to state the units of mass generally employed. How masses are actually measured in practice by the process called weighing will be described in the section on forces, as it is done by using of the force of weight. First, then, how can we apply exactly the same force to make it act on different portions of matter in such a way that we can measure the accelerations produced ? Weight affords us the easiest means of doing so ; for we may assume that NOTE.— Hereafter we shall speak of acceleration, change of direction of motion, distortion of bodies by stretching or bending, etc., as produced by the action of force, just as if force, and not the energy producing it, were the real cause. This is more convenient, and is almost universally employed, but the pupil will find himself freed from much confusion of thought if he will always bear in mind that the real cause is in all cases energy, and that force is never anything but a condition of matter incidental to the action of energy. experience has shown us that the weight of a given body at the same part of the earth's surface is constant, unless some matter is either added to or taken away from the body. Obtain a board (A B, Fig. 21) 8 feet or more long, 9 to 12 inches wide, and \\ to 2 inches thick. One surface must be very smooth, and must always be a perfect plane. Mark across the board black lines, one eighth of an or iron is preferable. They must be carefully turned in a lathe into true circles. The axles must be of brass or iron, and the wheels well centered. At one end of the board A B fasten a grooved pulley D, 4 or 5 inches in diameter. This must also turn very freely, and its top at D should be at the same height above the board as the point of attachment to the cart. A cord is run from E over D to a strong pan W. The board must be laid horizontally on a table, or on brackets 6 feet or more above the floor, to give room for the descent of W. We are to observe the accelerations produced in the loaded cart by a weight at W. To do this properly, it is necessary that all resistances, of which friction is the chief, should be reduced as much as possible. Oi\ the axles. Then remove the cord and pan by unhooking at E. Give the cart a gentle push toward D. It will roll a short distance, and then stop because of friction. Raise the end A of the board considerably, and push again. The cart will roll down the board with accelerated motion. Now lower A gradually, pushing the cart from time to time. By repeated trials a height will be found for A which will just keep the cart in very slow motion when started, and will not increase its speed. Leave the board in this position, for here the weight of the of error is almost removed. Now hook the cord on at E, and hang it over D. Put into the car some sand or shot, and a small amount of the same into the pan. We shall then have a force at W equal to the sum of the weights of the sand and pan (we may neglect that of the cord). This force will be always the same so long as no more sand is put in and none taken out. We have, therefore, a constant force which we will call W, and which tends to set in motion all the movable mass, viz., itself plus the mass of the cart and load. Some device is needed to stop the cart when in rapid motion. Tie up in a bag two or three pounds of sand or shot. Fasten to this a strong cord about two feet shorter than the board, and tie the cord to the rear end of the cart. Place the sand-bag upon the board at the end away from the pulley, and leave the cord loosely coiled or folded back and forth on the board. Place also a box or other shelf at such a distance below the pan W that the pan will rest upon it when the cart is two feet or less from D. If, then, the cart starts from the rear end of the board, it will move along freely till it reaches a point where E is one or two feet from D. Then W will cease pulling, because resting on the shelf, and the sand-bag will begin to act as a drag or brake to stop the cart. If a few inches of rubber tubing or coiled steel or brass spring be put in between the cart and sand-bag, the cart will be less violently jerked. lines on the board, and an upright pointer attached to the cart. The Motion produced by the Constant Force is accelerated. — Let us now see what the character of the motion is when the constant force W is moving the mass of the loaded cart and itself. Pull the cart hack till the pointer stands at a line near the starting end of A B. Let it go, and observe its motion. You will see that it moves slowly at first, and then continually faster and faster — that is, the motion is accelerated. To perceive this clearly, count as follows : At the instant of releasing the cart, say zero ; at the instant it crosses the next line (having passed over one space on the board), count one; at the third line, count two ; and so on. You will perceive in this way that each space is passed over in a less time than the preceding one, MEASUREMENT OF MASSES. 79 and that the motion is thus accelerated. If the friction were constant, and you had means of observing accurately, you would find that the motion was uniformly accelerated. The Bate of Acceleration by the same Force is less as the Mass moved is greater. — Take out some of the sand from the cart, and repeat the experiment. The cart will be found to move faster. If more load is put in, it will move more slowly. Thus, if we lessen the mass, the same force produces a greater acceleration ; if we increase the mass, it produces a less acceleration. To measure the rate of acceleration, which is desirable for some later experiments, make a pendulum by hanging any heavy body with a cord from any firm support, as in No. 9, page 60. The shorter the string, the faster the pendulum will swing. The time occupied by the cart in passing from a mark near the end A of 'the board to one near the end B can be observed by noting the number of swings of the pendulum. This can be best done by varying the length of the pendulum until it makes some whole number of swings while the cart is passing from A to B. By the laws of uniformly accelerated motion, the cart is equally accelerated when it passes over the space A B in equal times. If the cart passes from A to B in half a given portion of time, the acceleration will be four times as great (see page 20). If it travels in one third the time, the acceleration will be nine times as great ; and so on. To measure off Equal Masses of the same or of Different Kinds of Matter. — Leaving W unchanged, remove all the sand from the cart, and lay it carefully aside to be weighed in the next experiment. Put in its place some other kind of matter, for example, shot. The cart will now move faster or more slowly than with the sand in the last experiment, showing that the whole mass moved is either less or greater than before. By adding or removing shot, a quantity will at length be found with which the cart will move from A to B in exactly the same time as with the sand. Hence the rate of acceleration is the same — the same force (weight of W) is producing the same acceleration on two different collections of matter. We have, therefore, two masses, viz. (cart 4sand + mass at W) in one case, and (cart + shot + mass at W) in the fore, these two masses are equal. Further, as the mass of the cart and of W are the same in both cases, the mass of the shot must be equal to the mass of the sand. Thus we have a means of determining by a simple experiment whether two masses are equal, as well as of constructing equal masses. equal amounts, or counterpoise each other on a balance. Put the sand of the last experiment upon a spring-balance. The spring will be stretched by a certain amount. Replace the sand by the shot, and the spring will be equally stretched. The same result will be reached whatever kind of matter the equal masses are composed of, and however massive they may be.* counterpoise each other. The last two experiments can be made more satisfactory, although really no more accurate, by reversing their order. To do so, measure off by the spring-balance quantities of sand and shot which will stretch the spring equally. Put the sand into the cart and time its passage from A to B, using a suitable weight at W. Replace the sand by the shot, and time again. The time will be found the same. This proves that masses whose weights stretch the spring equally are equal masses, As this would be found true, however massive the equal portions and of whatever kind of matter, the converse proposition that equal masses stretch the same spring equally would be proved. Graded Sets of Masses. — The principle just explained enables us to construct a graded set of standard masses. If we take the sand of the foregoing experiment, or any mass of any substance, and divide it into two portions which stretch a spring equally or which counterpoise on an equalarm balance, the mass of each portion must be just half that of the original mass. Similarly we may divide the original mass or its parts into any desired number — 3, 5, 10 — of * It may at first sight appear that we have thus proved that equal masses have equal weights. This proposition will be shown to be true, but we can not prove it until after we have defined equal forces. As yet we have not shown that the spring can not be equally stretched by unequal f orqes of different kinds. STANDARD MASS. 81 equal masses, which will be J, -J-, ^ of the original mass ; or we can produce masses two, three, and ten times as great as the original. It is in this way that the graded sets of masses are originally arrived at. Such sets of masses are commonly spoken of as "sets of weights," as they are used in the process called weighing. This process depends upon principles respecting the equality and measurement of forces, and will, therefore, be described after they are discussed (page 86). In order to enable men all over the world and at all times to make measurements of mass which will be comparable with one another, it is essential that they should use as a basis of their measurements the same quantity of matter. This is accomplished by having a standard mass in terms of which all masses are expressed. Standard Mass. — As a standard quantity of matter with which to compare all other masses, we may adopt any given piece of matter which we choose. For instance, we may select a particular orange as our standard quantity. We should then say that any object having twice as much matter as the orange would have twice the standard mass, and so on ; but the orange is perishable and would need to be replaced from time to time, while our design in fixing a standard is to have a mass for reference so that measurements of mass made by one person may be comparable with those made by another, and those made to-day may be comparable with those made a century hence. Therefore our standard mass must be as nearly imperishable and unchangeable as possible, and must be carefully preserved. There are two fundamental standard masses to which all measurements in most civilized countries are referred. One is a piece of platinum carefully preserved by the French Government at Paris and called the "Kilogramme des Archives" (kilogramme of the archives). The other is a piece of platinum, in the office of the Exchequer at London, called the Standard Pound. kilogrammes. Copies of these standards in platinum and in other metals — i. e., pieces having as nearly as possible the same mass as the standards, are in the possession of various governments and are made the legal standards of the various countries. The copies belonging to our Government are in the keeping of the United States Coast and Geodet'ic Survey at Washington, D. C. The original standards and these chief copies are used only occasionally in order to protect them from wear arid accidental injury. Secondary copies made from them are in general use. changeable of all the metals. QUESTIONS. — What is mass ? In measuring mass, force, energy, etc., what are we obliged to take as a starting-point ? Define equal masses. Why can we not say equal forces instead of " the same force" in this definition ? What is the readiest means of applying the same force at different times ? Would any other force than weight lead to the same results if it were equally steady ? How do we arrange to apply the same force successively to different masses in the cart experiment ? In any case what is the total amount of matter to be moved in an experiment with the cart ? What kind of motion does a constant force produce on a constant mass ? How is this illustrated by the cart experiment ? How does the rate of acceleration by the same force vary as the mass varies ? How is this shown by the cart experiment ? If the cart moves from one mark to the next in two seconds on one occasion and in one second on another, how great is the rate of acceleration in the second instance as compared with that in the first ? Why? How can equal masses be measured off by the cart experiment ? Can a quantity of air and a quantity of lead have the same mass ? After the construction of two or more equal masses by the cart, what important proposition is next proved ? How can we construct equal masses by applying this proposition ? How can we construct a graded set of masses ? Why are sets of masses usually called sets of weights ? What is the object in having a standard of mass ? What is the chief quality necessary in such a standard ? Name and describe the two chief standards in general use. Equal Forces. — We must now learn how to measure forces — that is, how to compare the magnitude of one force with that of another. That action of energy which we call force is most naturally recognized (page 46) by the acceleration produced in free bodies, its amount may be measured EQUAL MASSES, EQUAL WEIGHTS. 83 by the amount of acceleration it causes ; but the acceleration produced by a given force has already been proved by experiment (page 80) to vary with the mass accelerated. Hence, in measuring forces, both the mass moved and the rate of acceleration must be taken into account. Let us start, then, with the following definition : tions upon the same or equal masses. Equal Masses have Equal Weights. — We may apply this definition in connection with the cart experiment to prove the proposition that equal masses have equal weights. Take several equal masses of any kind and of suitable amount. Prove that they are equal masses by ascertaining that they stretch the spring-balance equally, or that they counterpoise each other on the equal-arm balance. Put one of them into the pan at W. Load the cart until the weight at W produces a convenient acceleration. Time the passage from A to B as before. Remove the mass from the pan and put in another of the equal masses. Time again from A to B. Repeat with a third of the equal masses. The times will all be found equal ; but the mass moved was equal in all cases, being the total mass of (cart + load -{- pan -j- mass in pan); therefore, by the definition of equal forces, the forces causing these equal accelerations must have been equal. What were the forces? The weight of the pan plus that of one of the equal masses. These total weights were then constant ; but the weight of the pan was the same in each case ; hence the weights of the equal masses must also have been equal. The same result would be found with any equal masses of whatever material. We may, therefore, conclude that at the same point on the earth's surface equal masses have equal weights. We have thus a means of obtaining a force of any amount which we may desire, for the weight of two equal masses is thus proved to be twice that of one of the masses, and so on. For instance, if we desire to obtain a force of say 232 times that of the weight of one of the above masses, we have only to put together twenty-three and one fifth of the equal masses, and the weight of these will be the desired force. This gives us one easy and exact method of measur- ing forces, for we have only to balance the forces to be measured against the weight of known masses. We must remember, however, that the weight of a given mass is not precisely the same at all parts of the earth's surface, as further stated on page 91. While the experiments with the cart serve to illustrate roughly the law that equal masses have equal weights, yet for scientific purposes more exact proofs are necessary. These were first obtained by Newton through experiments with pendulums of different materials, and have since been verified in a great variety of ways. Spring-Balance or Dynamometer, for Measurement of Forces. — The spring-balance is really an instrument for measuring forces, and is therefore called a dynamom'eter (force-measurer). One form of it, represented in Fig. 22, consists of a coiled or spiral spring, whose upper end is secured to the top of the apparatus, and whose lower end is attached to a straight rod carrying an index or pointer and having a hook at the bottom. If an object is hung upon the hook, its weight stretches the spring by a certain amount and holds the index steadily at some point along the scale, thus indicating the weight of the object. This scale is originally graduated by hanging upon the hook various known masses and marking their weights opposite the index. For instance, a If an object of unknown weight is hung on the hook, the index will stand at a certain position. Suppose this happens to be half-way between the three and the four pound mark. Then the weight of the object is equal to the weight of a mass of 35 pounds, or, we may say, for brevity, its weight is 35 pounds. If any other force than a weight stretches the spring, then the index-reading gives the amount of that force. For instance, suppose that the balance were horizontal, and that a piece of iron were fastened to the hook with a magnet beyond it, and that their mutual attraction stretched the spring so that the index stood at the four pounds mark. Then we should know that the force of attraction between the iron and the magnet was equal to the weight of a mass of four pounds. Similarly we might measure any kind of constant force. Weights by Equal- Arm Balance. — For reasons which will be explained when the instrument is described, the equal-arm balance swings evenly when the weights of the objects in the two pans are equal. The usual method of weighing is to place the object to be weighed in one pan, and in the other to put masses from a graded set, changing these until the balance swings equally on each side of its position of rest. The weight of the object is then equal to the weight of the known masses in the other pan. range such a balance for measuring other forces than weight. The process of weighing is one capable of great precision and delicacy. Equal-arm balances have been constructed which show a difference of one ten-millionth part of the whole load on the pan. Measurement of Masses by the Equal-Arm Balance and by the Spring-Balance. — As equal masses have equal weights, it is evident that the equal-arm balance enables us to measure masses easily in terms of a graded set * Observe that the pound, like the kilogramme, originally and properly denotes a certain mass of matter, but that for convenience in speaking of weights we say "the weight of a pound," or of a kilogramme, instead of using the correct but longer phrases, " the weight of a pound of matter,11 "the weight of a pound-mass,11 etc. So in the case of other forces, we speak of " a force of one pound," meaning " a force equal to the weight of a pound of matter." It is important to keep this in mind to avoid confusion. masses, of course, are equal. For instance, if, to balance a certain object, it is necessary to use a two-pound, a one-pound, and a half-pound mass in the other pan, the object has a weight equal to that of a mass of 3-5 pounds. Its mass is thus shown to be 3'5 times the mass of a standard pound. Masses, the Force must be proportional to the Mass moved. — Put on the cart a small load, and on W enough weight to produce a convenient acceleration. Time the passage from A to B. Weigh W, also the cart and contents together with W. Double the force at W and add to the load upon C until it goes from A to B in just the same time as before, and hence has the same acceleration. Weigh C and W together again. The weight, and therefore the mass, will be found to be twice as great as before. Double the force at W and double the total mass, and observe that the cart passes from A to B in the same time as before. Make W and the total mass five times as great as at first, and notice that the cart still travels from A to B in the same time. Hence, to produce the same acceleration on different masses the force must be proportional to the mass moved. Acceleration of Constant Mass proportional to the Force. — Load the cart rather heavily. Time the movement from A to B as before. Next weigh W — i. e., pan and contents. Take from the load of C a weight equal to three times W, and put it into the pan in addition to the former load. We know then that we have made the force at W four times as great, but have not changed the whole mass to be moved. Time the motion from A to B again. You will find the space is traversed in half the time. same space is one half as great, the acceleration is four times as great. If we make the force (weight at W) nine times as great as at first, the time will be found to be one third, and therefore the acceleration to be nine times as great, and so on. Thus the acceleration of the same mass is four times as great when the force is four times as great, and nine times, when the force is nine times — that is, with a constant mass, the acceleration is directly proportional to the force applied. A Constant Force is proportional to the Product of the Mass into the Acceleration produced by it upon that Mass. — The statements of the two foregoing paragraphs may be combined in one, viz., that to produce in a given mass a given acceleration, the force must be proportional to the product of the mass into the acceleration. For instance, suppose that we begin with a given mass and force. This force will produce a certain acceleration. If we double the mass, twice the force will be necessary to produce the same acceleration ; but if we desire to increase the acceleration, say to treble it, we must also treble the force. Hence, to give the double mass a trebled acceleration, we must apply six times the first force. To make a mass five times as great as the given mass move with seven times the acceleration, would require a force of 5 x 7 = 35 times the first, and so on. Conversely, if a body is seen to be moving with a uniform acceleration, we know that it must be under a uniform force proportional to the product of its mass into its acceleration. Newton's Second Law of Motion. — The universal experience in regard to the direction and amount of effect of forces is stated in Newton's second law of motion. In this law, " change of motion " means the product of the mass into the acceleration produced by the action of the force in question upon a free body of the given mass. the same kind. If, for instance, we say that the side of a room is eighteen feet long, we mean that its length is eighteen times the length which we call a foot. If we say that two towns are 23 -54 miles apart, we mean that their distance apart is twenty-three and T%- times the distance which we call a mile. Here the foot was the unit of distance in the first case, and the mile the unit of distance in the second. We might have expressed either distance in inches, yards, rods, metres, kilometres, or any other unit which we chose to use. Thus the choice of a unit is wholly arbitrary. We can select a unit of such size as to be convenient for the purpose in hand, and there may be, and usually are, many different sized units of the same kind, as just shown for units of length. But it should be remembered that units for measuring the same kind of quantity are all and always of the same kind as that quantity, and are merely arbitrarily chosen amounts of that quantity. They differ only in size. Thus, the inch, foot, metre, mile, etc., are a few of the various units of length. They are all the same kind of thing, viz., distances. They differ only in size. Similarly, the quart, litre, gallon, hogshead, gill, etc., are units of capacity; they differ in nothing but magnitude. This is true, however complicated the nature of the quantity measured. The Idea of Standards must be kept distinct from that of units. A standard yard is merely a metallic bar with lines ruled upon it, whose distance apart at a stated temperature is defined by law to be one yard. The yard is used as a unit of length. It is not, however, the only unit of length, and in fact is merely a fixed distance by reference to which various other units of length can be defined and reproduced. Thus, the foot is equal to one third of that distance, the mile is equal to 5,280 such feet, etc. UNITS. 89 upon it whose distance apart, at a stated temperature, is denned by law to be one metre. This distance is about 3-4 inches longer than the yard. The metre is exactly 39-3702 inches. We may use any multiple or submultiple of these standard distances which we choose as units in any particular case, or indeed any other distances ; but, in order that our measurements should convey an exact idea to others, they must be expressed in units whose relation to the standards is accurately known. The standard pound and the standard kilogramme are, as has been stated, standard masses ; but neither is commonly used as the unit of mass. For reasons which will appear, the units of mass actually employed are either larger or smaller than these standards, but bear a perfectly definite and known ratio to them. In the following paragraphs, the scientific units will be defined and described first. The engineering and other units will be summarized later. The Unit of Time commonly adopted is the second. The Unit of Mass employed in almost all scientific work is the mass of one gramme, or the one-thousandth part of the mass of the standard kilogramme. Instrument-makers supply graded sets of masses. These may contain any amounts desired. A convenient set contains pieces of one kilogramme, and of 500, 200, 200, 100, 50, 20, 20, 10, 5, 2, 2, 1 grammes, and so on, for such decimals as are desired. The system of units based on the centimetre, gramme, and second, is called the centimetre-gramme-second system, or the C. G. S. System. In computations where this system is to be employed, all quantities of length, mass, or time, must be reduced to, and expressed in, centimetres, grammes, or seconds, before being used. A similar statement holds The Unit of Force, in all systems, is a force which will produce unit acceleration upon unit mass. In the C. G. S. system, the unit acceleration is one centimetre per second. The unit of force — C. G. S. — is then a force which can produce an acceleration of one centimetre per second on a mass of one gramme. This unit of force is called the Dyne. Any constant force F, which is producing in a mass of M grammes an acceleration of a centimetres per second, must be equal to MX a dynes (i. e., F = Ma) ; for to produce on a mass of M grammes an acceleration of one centimetre per second, would require M dynes. To produce on the same mass an acceleration of a centimetres per second would require a times this force — i. e., Ma dynes — or, in any system of units, to produce an acceleration of a units on a mass of M units would require a force of Ma units. EXAMPLE. — Suppose that we observe a body moving with a uniform acceleration of 250 centimetres per second, and find by the balance that the body's mass is 400 grammes. What is the amount of the force producing the acceleration ? F = Ma = 100,000 dynes. To obtain an idea of how large this unit of force is as compared with that very familiar force, the weight of some standard body, we may take a body whose mass is one gramme and let it drop from a height. It will be accelerated by a constant force, its weight, and will therefore fall with a uniformly accelerated motion. By exact experiment, that acceleration is found to be in the latitude of Boston, and at the level of the sea, about 980-4 centimetres per second. The force with which the mass of one gramme is drawn toward the earth — i. e., the weight of a gramme — is then much greater than one dyne. A dyne would have given it an acceleration of only one centimetre per second, but it received an acceleration of 980-4 centimetres per second. We have proved that the force is proportional to the acceleration. Hence this force must have been equal to 980-4 dynes; or, to state it in another way, F=Ma. M=l gramme, a = 980-4 centimetres per second, F= I X 980-4 = 980-4 dynes. The weight of the gramme is, therefore, 980-4: dynes in latitude 42° at sea-level. WEIGHT DIFFERS WITH LATITUDE. 91 We thus have an easy way of producing the dyne at any time. Take the mass of ^th of a gramme. This mass will be attracted toward the earth by a force of exactly one dyne. You will see from this also that a body whose mass, as found by the balance, is M grammes, weighs 980 x M dynes. For instance, a body whose mass is 300 grammes weighs — i. e., is attracted to the earth by a force of — 980 x 300 = 294,000 dynes. The dyne is thus a very small force. It is convenient for much scientific work, especially in electricity and magnetism, but is not so for engineering work where large forces are to be dealt with. A more convenient unit for such work is described later. It is a fact of importance that if the mass of a gramme is dropped near the sea-level at the equator, it will have an acceleration of only 978-1 centimetres per second ; at latitude 45° sea-level, the acceleration would be 980-6 centimetres per second ; at the pole, it would be 983-1 centimetres per second. The letter g is commonly used to denote the acceleration due to weight. This acceleration is found to be very slightly less above the sea-level ; for example, at 45° sea-level it is 980-6, but at 1,000 feet above the sea it is about 980-5. As has been shown, it is due to the weight of the body. If, therefore, the same body be taken to various places, its acceleration will be different, and its weight will be different in the same proportion. Thus, the weight of the same or an equal mass at the equator is about jfoth part less than that at the poles. In general, the weight in dynes of a gramme at any place where the acceleration of gravity is g, will be g dynes. To measure the Force with which a body is attracted to the earth — i. e., to ascertain its weight — we may put it into one pan of an equal-arm balance (page 163) and place in the other pan standard masses until we have just enough to counterbalance it. Thus the weight of the masses just equals that of the body. Suppose we count up the standard masses used, and find them to be 340 grammes. We know then two things: first, that the mass of the body is 340 grammes ; second, that the weight of the body is 340 X g dynes ; and, knowing g to be 980-4 centimetres per second, we know that the weight is 340 X 980 = 333,200 dynes. It is confusing to students when they first notice that all bodies, whatever their mass, fall to the earth with equal acceleration ; but it is easily understood by considering that the weight is proportional to the mass, so that, although the force causing the heavier body to fall is greater, the mass to be accelerated is greater in the same proportion. Hence the acceleration must be the same. Prove this by dropping, side by side, objects of equal and different weights. The spring-balance has been described as a convenient instrument for measuring forces. In order that it may measure them directly in terms of the C. G. S. unit, it should be graduated by hanging upon it masses of ^f^, ^f^, etc., grammes, as the weights of these masses are 1 dyne, 2 dynes, etc. But as any unit of force differs from the dyne only in amount, we may use a balance graduated in any unit and reduce to dynes by multiplying by a suitable factor. Thus, the weight of the standard pound at London is equal to about 44,500,000 dynes. If a force were measured by a spring-balance graduated at London in pounds and found to be 2-1 pounds, the force would be about 93,450,000 dynes. Momentum. — If a body, of mass J/, is moving with a velocity F, the product M V of its mass by its velocity is called the Momentum of the body. EXAMPLE. — If a body with a mass of 10 grammes is moving with a velocity of 5 centimetres per second, then its momentum would be M V= 10 x 5 = 50 units. This momentum might have been produced by any uniform force F acting for a suitable time t. If it had been produced in t = 2 seconds, then the force must have been F = M V -5- t = 50 -r- 2 = 25 dynes ; if in a time of 0-002 second, then the force must have been F = 50 -f- -002 = 25,000 dynes; if it had been produced by a force of 5 dynes, the time during which the force must have acted would have been t = MV-r- F = 50 -5- 5 = 10 seconds. If the force causing the momentum is not constant, then the force computed by the expression above would be the average value of the force during the time t. The average value is that amount which we should find if we could divide the time into extremely small intervals, and could find the amount of the force at the middle of each interval, and should then take the average of all these values — that is, add them all together and divide the sum by their number. IMPULSE. 93 shown that Ft = M F, hence we may say that the impulse of a force is measured by the momentum produced. There are many cases in which forces act for short times only, as when the gases caused by the burning powder in a gun are forcing out the bullet, or the bowstring is speeding the arrow, or one elastic body strikes another, as when a ball is struck by a bat. In such cases, the force is not constant but varies rapidly, besides being of very brief duration. Here we can not usually know either t or F, but only M V, so that the amount of the impulse is found from MV. Time required to set Matter in Motion. — However large the force acting, and however small the mass acted upon, some time is required to impart any velocity. V are very small and F is very large, t will necessarily be small, but can never be zero. To make t zero would require an infinite force F, and anything infinite is beyond our physical experience and beyond our powers of conception. QUESTIONS.— Define equal forces. Prove that equal masses have equal weights. Does this fact require proof ? How does this give us a means of obtaining any desired amount of force ? Describe the spring-balance. Why is it called a dynamometer ? How is the scale of the spring-balance originally graduated ? How would you use a spring-balance to measure the weight of a body ? How would you use it to measure some force not in a vertical direction ? In such a case, would you have to make any allowance for the effect of the weight of the parts of the balance itself ? Is the standard pound a mass or a weight ? What is weight ? When we speak of a force of one pound, what do we mean ? Describe the process of obtaining the weight of an object by an equal-arm balance. Is it a process capable of accuracy ? How does the process of measuring the mass of an object by a balance differ from that of measuring its weight ? By an experiment, 2'5 pounds are found necessary to balance an object ; state in full what the weight of the object is and what its mass is. Why and how much is the spring- balance in error when used at other places than that for which it is graduated ? If one mass is four times another, how many times as much force is necessary to produce upon it a given acceleration ? Define acceleration. If to a given body you apply successively forces of 2 and 4, what will be the relative accelerations ? What is the relation between the force and the acceleration produced by it upon any mass ? Is this true of any but a free body ? State Newton's second law of motion. What is meant by a unit ? What determines the size of unit selected for a given purpose ? In what respect do different units of the same kind differ ? Do they differ in any other respect ? What is the scientific unit of length ? Of time ? Of mass ? What is the C. G. S. system ? In what units must lengths be expressed before being used in computations ? Masses ? Times ? Why ? Define the unit of force in general. What is the C. G. S. unit of force called ? Define it. Show how in these units F=Ma. Show what the weight of a gramme is when expressed in dynes at a place where the acceleration of gravity is 980 centimetres per second. How does this enable us to obtain a force of any desired number of dynes at any place ? Why do all bodies, whatever their mass, tend to fall under gravity with equal acceleration ? If a body were found by a spring-balance to have a weight of 3 pounds avoirdupois, what would be the force in dynes with which it is attracted to the earth ? acting for a given time is equal to the product of the force into the time. A body of a mass of 20 grammes is moving with a velocity of 30 centimetres per second. What is its momentum ? If this momentum were produced in 5 seconds, how great must be the constant force required ? If it had been produced by a constant force of 15 dynes, how long must that force have acted upon the body ? Suppose the force had been variable and had produced this momentum in 10 seconds, what must have been the average amount of the force ? Matter and Motion are the only Essentials of Energy. — We have learned that matter can possess energy only by being in motion. We know also that for an onwardmoving body the energy is greater as the mass and the velocity are greater. This has been shown by the experiments with the rolling balls, and is illustrated in every-day experience. The energy of a body, then, depends on its mass and its velocity. Energy of Rotation. — A body may be rotating, but yet have no onward motion. In such a case each particle of the body possesses at any given instant a perfectly definite velocity, and therefore an amount of energy which would be denoted by \MV, where M is the mass and V the velocity of the particle. If we take the sum of all these quantities for the whole body, that sum will represent the total energy of rotation of the body. Rotation and onward motion can, of course, exist at the same time, so that a body may simultaneously possess energy from both motions. The heavy fly-wheel of an engine in motion possesses an immense energy of rotation. Slowing down the speed of the wheel implies that a large amount of energy is taken from it, and this requires some time. Starting it again similarly requires energy and time. The flywheel, therefore, is a great help toward keeping the speed of the engine uniform. Think of the enormous energy of rotation of the earth or of the sun on its axis ! MEASUREMENT OF WORK. Work is only a name for the process of transfer or transformation of energy. It must, therefore, be expressed in the same unit as energy — that is, in ergs. Thus, if a body has imparted to it an amount of energy equal to 100 ergs, then the amount of work done upon it in imparting that energy will also be 100 ergs ; and the amount of work which the body can do in giving up that energy will be 100 ergs. * For the sake of brevity and convenience, we use the expression " amount of work done,11 or simply "work done," instead of "amount of energy changed in place or form.11 Remember that, when we speak of measuring the amount of work done, we mean measuring the amount of energy changed. In many cases where the energy is transformed when the work is done, it is impossible to measure directly either the amount of energy given up by the body doing the work, or the amount received by the body upon which the work is done. For instance, if you raise a heavy body from the ground to a table, you expend muscular energy and produce potential energy. Now, it is not practicable to measure the muscular energy directly nor the energy which produces the condition which we call potential energy ; but we have, nevertheless, a means of finding how much energy is transformed, as will now be shown. Work against or by a Constant Force. — If a body is moved through a distance s against or by a constant force F, the amount of work done is equal to the product of the force into the distance — it may be expressed by W = Fs. A body whose mass is 40 grammes falls freely through 10 centimetres at a place where g = 980 cm. sec. ; how much work is done upon it by gravity f Its weight is 40 x 980 = 39,200 dynes. The work done is therefore W = Fs — 39,200 x 10 = 392,000 ergs. ergs. Why I Compute the energy from its acquired velocity. E = %M F2. M — 40 grammes. By the laws of accelerated motion, F2 = 2 gs = 2 x 980 x 10 = 19,600 cm. sec. Therefore, E = £ x 40 x 19,600 = 392,000 ergs. This result is necessarily the same as that obtained by the other method, for the two formulae Fs and \MV* must, of course, be equivalent. How much work must be done to stop this body f 392,000 ergs. How much to keep it moving with the acquired velocity? None, if there is no resistance to motion. How high would it rise if thrown vertically upward with this velocity f The Amount of Work done is the same, whether the body is moved slowly or fast. For instance, in the first of the examples just given, the amount of work is obviously the same, however long or short the time occupied in raising the body may be. The amount of work depends only on F and s, and neither of these changes with the time. The will be separately considered. The amount of work done is the same when the body moves freely and thus stores up the energy in itself as energy of onward motion, and when the body moves against resistance, transforming the energy or transferring it to other bodies. The " weight " of a clock will have done upon it by gravity the same amount of work in the course of its descent, whether it drops freely, or whether it descends in its usual slow manner, continually transferring the energy given it by gravity to the works of the clock where (in overcoming friction) this energy is transformed mostly into heat. EXAMPLE. — A clock-weight has a mass of 40 grammes, and descends in a day through 10 centimetres. How much work is done upon it by gravity ? Gravity does upon it 392,000 ergs of work (see preceding example) whether it descends slowly or falls freely. The Amount of Potential Energy relatively to a given point, which belongs to a body because of its position and the force acting upon it, is equal to the energy which it would acquire in moving freely to that point, or to the work which would be done upon it by the force. selected for the examples because it is convenient and familiar. QUESTIONS.— What is energy ? How can matter possess energy ? Is there more than one way in which matter can possess energy ? What, then, do we mean by different forms of energy ? What is potential energy ? If a portion of matter of mass m has a velocity v, what is its energy ? Relative to what does it possess that energy ? What is an erg ? The air in an ordinary steam-car has a mass of about 300 pounds, or 140,000 grammes. Suppose the car to be moving at a rate of about 21 miles an hour, which is about 1,000 centimetres per second, what is the energy of the air relative to the ground ? Suppose the car itself has a mass of 20 tons, what is the energy of the air as compared with that of the car ? How does a body in rotation possess energy ? Relatively to what does it possess energy ? Do its parts possess energy of onward motion relative to one another ? Explain the action of a fly-wheel. What is work ? What is the C. G. S. unit of work ? How much work must be done to set the air of the problem above into motion or to stop it, neglecting all losses ? If any body is moved through a distance s against a constant force F, how much work is done ? Give proof. In what direction must s be measured ? A body whose mass is 9,800 grammes is raised vertically 70 centimetres. How much work is done ? What is the potential energy of the body at its new position as compared with its old ? Where is the actual energy to which this socalled " potential energy " corresponds ? If a body is moving with accelerated motion, what should we mean by saying that it was accumulating or storing up energy ? If a body falls freely through 10 feet in one case, and in another descends only very slowly and uniformly through the same distance, does it take up from the energy of gravitation the same amount of energy in each case ? Does "• gravity " do the same amount of work in each case ? What becomes of the energy in each case ? Suppose that instead of falling freely the same body falls with accelerated motion but at a less rate than if free, how much work is done by gravity ? How much of the energy remains in the body ? What becomes of the remainder ? AND WORK. British Engineering Units. — The C. G. S. system of units is almost universally employed in modern scientific work ; but for engineering and commercial purposes several other systems are in common use, partly for convenience, and partly from' the continuance of long-established custom. The units of these various systems differ in no other respect than in magnitude. The British engineering unit of length is the foot (one third of the standard yard) ; the unit of time is the second in general, but frequently the minute or hour, in dealing with long times ; the unit of force is the weight of one pound — i. e., the force with which the quantity of matter called the standard pound is attracted to the earth. British Engineering Unit of Mass. — Having thus defined the unit of force, we must next deduce the unit of mass. By definition (page 90), the unit force is a force which will produce a unit acceleration in a unit mass. In the British engineering system, a force equal to the weight of one pound would produce an acceleration of one foot per second when acting upon a unit mass. Let a mass of one B. E. UNITS. 99 pound fall freely. The force accelerating it is the weight of one pound. The mass accelerated is the pound mass. What acceleration is produced? Exact experiments show that the acceleration will be very nearly 32'2 feet per second. The acceleration, then, is 32'2 times what the unit of force would produce in the unit of mass. Hence the mass of one pound is only $%.% part of a unit of mass, and the Unit of Mass in the British Engineering (B. E.) System must be the mass of 32-2 pounds — i. e., 82-2 times the mass contained in the standard pound. This unit has no special name. If, then, we find by the balance that an object contains a certain number of pounds of matter — e. g., 80-5 pounds — then its mass expressed in B. E. units of mass would be 80-5 -r- 32-2 = 2-5 units. Therefore, to find the number of B. E. units of mass in an object, ascertain by the balance the number of pounds mass it contains and divide by 32-2. The B. E. unit of mass is simply a larger mass than the mass of the standard pound, just as the foot is a larger unit of length than the inch. As, then, we can express a distance of 54 inches by calling it 54 H- 12 = 45 feet, so we can express a mass of 70 pounds by calling it 70 •• 32-2 = 2-17 B. E. units of mass. The B. E. Unit of Work is the foot-pound— that is, the work done in moving an object through a distance of one foot by or against a force of one pound. The B. E. Unit of Energy is, of course, the same as that of work, viz., the foot-pound, as the amount of work is merely the amount of energy transferred or transformed. EXAMPLES. — How much energy would a ton acquire in falling through 5 feet ? E — W = Fs = 2,000 x 5 = 10,000 foot-pounds. Or in falling 5 feet it would acquire a velocity (page 20) such that F2 = 2as, and a = 32-2 feet /. 72 = 2 x 32-2 x 5 = 322 feet per second. .-. E = second. .'. E = £ x 1,863 x 882 = 7,210,000 foot-pounds. Therefore the engine must give out 7,210,000 foot-pounds of energy ; or, in other words, must have done upon it 7,210,000 foot-pounds of work (by brakes, etc.) before it can stop. This would be equal to the work of raising 7,210,000 pounds, or 3,605 tons, one foot vertically against gravity, or one ton 3,605 feet (about three fourths of a mile) — or to the energy These results may give you a rough idea of the enormous energy of two trains coming into collision at high speed. But think how small this is compared with the energy of the earth moving in its orbit ! The French or Metric Engineering System is based on the metre, second, and kilogramme, instead of on the foot, second, and pound (see page 540). " " 1 kilogramme = weight of 2'205 pounds. 1 foot-pound = 13,560,000 ergs. 1 kilogrammetre = 98,100,000 ergs. 1 foot-pound = 013825 kilogrammetre. Energy of other kinds than onward motion and potential energy, viz., heat-energy, energy of vibration, electrical energy, etc., may always be expressed in ergs, foot-pounds, or any chosen unit, and for some purposes are so expressed. Quantities of energy expressed in other units can be reduced to ergs or foot-pounds, if we know how many of the special units are equivalent to an erg or a foot-pound. QUESTIONS.— On what account are the C. G. S. units not convenient for engineering work ? What is engineering work ? In what respect do other units differ from these ? Is a unit anything but an arbitrarily chosen quantity ? Can quantities of the same thing differ except in amount ? Name the B. E. units of length, time, and force. Why should the B. E. unit of force be denned for a certain locality ? What is the unit of mass in the B. E. system ? What is the standard mass ? Show how the unit of mass is deduced. Having given the mass of a body expressed in pounds, how would you find its mass expressed in B. E. units of mass ? What is the mass in B. E. units of the air in the car of a In what unit must distances be expressed before being used for computation in the B. E. system ? Times ? Masses ? What would happen if you neglected to express them in these units ? What is the B. E. unit of work ? Of energy ? How much is the least work in B. E. units necessary to be done to lift a man whose mass is 150 pounds from the bottom to the top of the Washington Monument ? How much would his potential energy due to gravitation be increased by that elevation ? How much energy of onward motion would a man's body possess when it reached the earth falling from that height if not resisted by the air ? What would be ^he energy in B. E. units of onward motion of the steamcar of a former problem ? How much work in B. E. units must be done, neglecting losses, to start or stop the car ? If the engine pulled with a constant force upon a train of five such cars, and was required to pull for one fifth of a mile before it could bring them from rest into motion at the stated speed, with how much force, B. E. units, must it pull, all friction and air resistance being neglected ? How much work, B. E. units, must the engine do simply to get the mass of this tram up to speed regardless of resistance ? Power. — Attention has been called to the fact that the amount of work in any given case is the same, whether the work is done rapidly or slowly. To lift a ten-pound weight 5 feet high requires 50 foot-pounds of work, whether the action occupies a fraction of a second or a century. But the rate at which work is done in the two cases would be very different. By rate of work (also called activity) is meant the amount of work done^?er unit of time. The term POWER is used to denote the rate at which a source of energy is capable of doing work — i. e., of giving up energy. The relation between power and work is the same as that between velocity and motion — power being rate of work, velocity rate of motion, both rates being with respect to time. The B. E. unit of power is the Horse-power. It is a rate of work of 550 foot-pounds per second, and very roughly represents the rate at which a horse can keep up continuous work. Thus, to raise a body weighing 550 pounds in one second through a vertical distance of one foot against gravity, would require work at the rate of one horse-power. This is an arbitrary and not altogether convenient unit, but it is in very general use. Other units of rate of work are employed in electrical measurements. An electric motor is required to run an elevator ; what must be the nominal horse-power of the motor f To answer the question, we must know the rate at which work must be done upon the elevator. Suppose, then, that the elevator is required to rise at a speed of 30 feet per minute, when the total load is 2 tons, including the weight of the elevator. Then, neglecting friction, the rate of work must be 2 x 2,000 horse-power of motor which will do the work. In practice, a motor of twice this capacity would be used, because the work required to be done against friction is usually very great. Action and Reaction. — We have seen that two bodies, or at least two particles of matter, are necessary to the existence of a force, and that each possesses a tendency to acceleration. When we deal with the effect of the force upon that one of the bodies with which we happen to be concerned, regardless of the other, we speak of the effect as the action of the force. If we consider the effect of the force upon the other body, we speak of it as the reaction of the force. Whenever, then, there is a force, there must evidently be both action and reaction. This and some other facts are expressed by Newton's Third Law of Motion. — " To every action there is always an equal and contrary reaction ; or, action and reaction are equal and opposite." Hold a book in your hand. The book and the earth tend to approach each other — that is, there is a force of attraction between them. The action of this force is the tendency of the book to be accelerated toward the earth, or its motion if it is allowed to fall. The reaction is the tendency of the earth to be accelerated toward the book, or its motion if allowed to move. Notice that the direction of motion of the earth and book would be toward each other — i. e., exactly opposite. ACTION AND REACTION. 103 As shown on page 92, the product of the force into the time for which it acts, is equal to the momentum produced. In the case of action and reaction, the force is the same on both bodies concerned, and so long as it acts it affects both bodies. Hence the product of the force into the time must be equal for both, and the momentum generated in one must be equal to that of the other. That is, if m^ and vv be the mass and velocity of one body, and w2 and v^ those of the other, then m^v^m^v^. This is true of all cases of action and reaction, of impact of elastic 'bodies, of attraction and repulsion of all kinds, etc. acceleration occurs. Reaction would be measured in the same way. The terms action and reaction are often applied, though incorrectly, to counterbalancing forces. For instance, when an object rests upon a table, the elasticity of the table is called into play, and the table exerts an upward force upon the object equal and' opposite to its weight. But there are here two distinct forces, and the case is not one of action and reaction of a single force. The fact that a man can not lift himself by pulling at his boot-straps is an example of balanced forces, not of action and reaction. Would a huge bellows operated in the stern of a sail-boat produce a wind that would move the boat I Why ? QUESTIONS.— What is meant by rate of work ? Power ? Activity ? What is a horse-power ? Is it an amount of energy ? Why ? How does an amount of work differ from a rate of work ? Can a force exist without affecting at least two bodies or particles of matter ? Is force a tendency of one body to approach another, or of two bodies to approach each other ? What is the distinction between action and reaction ? Are they the effects of the same or of different forces ? Give examples of them. State Newton's third law of motion. How many cubic feet of water will be raised in an hour from a well 50 feet deep, if the rate of piimping be 15 horse-power ? (Reckon one horse-power as equivalent to 8'8 cubic feet of water lifted 1 foot high per second, and the weight of a cubic foot of water at 6^^ pounds.) ^ A cannon-ball weighing 500 pounds is shot from a gun weighing 20 tons. What are the relative momenta ? If the ball leaves the gun with a velocity of 2,000 feet per second, what is the velocity of recoil of the gun ? Momentum of ball Suppose a buUet weighing one ounce and moving with a velocity of 1,000 feet a second is found to penetrate 2 inches into a plank. What must be the average amount of the force in B. E. units exerted by the bullet ? We must first find E. One ounce = ^ pound : therefore, mass of bullet in B. E. units = T^ -• 32'2 = 0-00194 B. E. units. E = £ x '00194 x 10002 = 970 feet per pound. Now s = 2 in = A person weighing 130 pounds walks up a flight of stairs composed of 45 steps, each 8 inches high. How much work in B. E. units is the least that he can do ? He must lift himself through 45 x 8 inches = 30 feet. He must, therefore, do W = F s = 130 x 30 foot-pounds of work. What would be the potential energy of the person when half-way up ? A clock-weight has a mass of 2,000 grammes, and descends in a day through a weight of 10 centimetres. How much work is done upon it by gravity ? W = Fs(F = 2,000x980 dynes). Ans. 19,600,000 ergs. We may make use of the cart experiment to determine the number of dynes in the weight of a gramme mass. Suppose we make the mass in W, including the pan, 100 grammes, and vary the mass in the cart until it moves over 180 centimetres in 3 seconds, and that we then find by the balance that the whole mass M of C and W is 2.450 grammes. What is the amount of the accelerating force, viz., the weight of 100 grammes ? (F = M a.) Ans. 98,000 dynes. How many dynes in a one-gramme mass ? Suppose a steamer to be sailing at the rate of 12 miles an hour, and a ring to be tossed at the same rate of speed across the deck in a direction perpendicular to the course of the vessel ; what is the velocity of the ring relatively to the surface of the sea ? Dynamics. — That branch of Physics which investigates the action of force and energy is called Dynam'ics (from a Greek verb meaning to be able). That part of Dynamics which deals with balanced forces is known as Stat'ics (from a Greek verb meaning to cause to stand) ; that part which treats of motion as produced by force, we call Kinet'ics. The sections on Energy and Force, which you have already studied, relate to Dynamics. Composition of Forces. — Force, being a tendency to acceleration, and being measured oy the acceleration produced on unit mass (P= Ma, page 91), may be represented by lines, in the same manner as velocities and motion. Let A B, Fig. 23, represent in magnitude and direction the acceleration which a given force F would produce on a free unit mass ; then A B also represents in magnitude and direction the force F itself, for this acceleration is equal to, and in the direction of, the force. tion produced by F2 alone. Then A C represents F2. The resultant acceleration would be, as shown on page 24, the diagonal A D of the parallelogram ; _, and this acceleration is that which would be produced by a single constant force acting in the direction A D, and represented in magnitude by the length of A D. The free body at A acted upon simultaneously by the two forces FI and F3 (A B and A C) would move precisely as if acted upon by the single force R, equal to, and in the direction of, A D. EXAMPLE. — Two constant forces, FI= 3 pounds and F2= 2 pounds, act simultaneously on a body at an angle of 60° with each other. What is their resultant I Draw the straight line A B (Fig. 23) of a length 3 units (take three quarters of an inch) to represent Jf\. Through A draw A C of a length 2 units (two quarters of an inch), and at an angle of 60° with A B, to represent F. Complete the parallelogram A B D C. Draw the diagonal A D. Measure its length. You will find it to be 3f6 quarters of an inch long. Then the combined action of Ft and F is equivalent to that of the resultant R = AD = 36 pounds acting relatively to F! and F2 in the direction A D. Equilibrium of Forces. — The principle of the composition of forces shows that any number of forces acting simultaneously at a point are equivalent to a single resultant force. It has also been shown (page 48) that to counterbalance a single force — that is, to prevent acceleration — we must apply an equal and opposite force. Therefore, to counterbalance a set of two or more forces, acting at one point, there must be applied at that point a force equal and opposite to the resultant of the set. Drive smooth wire nails into an upright board at B and C. Put upon them spools, or, better, large metallic or wooden pulleys. Knot together firmly three cords at A. Hang one cord over the pulley B, another over C, and let the third carry the weight D. Upon D suspend a weight of 5 pounds, on C a weight of 2-5 pounds, and on B a weight of 4 pounds. After a moment the apparatus will come to rest. A little jarring will reduce the error from friction. Thore will then be three forces at A acting along A B, A C, and A D respectively. As the point A is at rest, these forces are balanced, or, as it is said, are in Equilibrium (from Latin words meaning equal balance). EQUILIBRIUM OF FORCES. paper, and draw lines through these points, and you will have lines A E, A F, A G, of Fig. 24. Select any two of these forces, say F and G. Lay off along A F a distance A c of 2'5 units (in Fig. 25 the unit is about three sixteenths of an inch) to represent the force F. Along A G lay off a distance of A d of 5 units to represent the force G. Complete the parallelogram and draw the diagonal A /. Measure A / carefully, and you will find it to be about 4 units — that is, the resultant of F and G is about 4 pounds and is in the direction A /. In other words, the two forces, acting in the lines A F and A G, are equivalent to a single force of about 4 pounds acting to pull A in the direction A /. To balance this single force would require, according to our previous statements, another force equal to it and opposite in direction. Consult the data, and you will see that the third force E is almost or exactly 4 pounds. Observe your diagram, and not;e that the resultant A / is almost or exactly in the same line with A E, but in the opposite direction. therefore, been experimentally proved. They could be similarly demonstrated for several forces by using more pulleys, as in Fig. 26, and constructing resultants (see page 25). The student is advised to put together some such simple apparatus, and to experi- ment for himself. Resolution of Forces. — As we may resolve a given acceleration, velocity, etc., into components in any specified directions, so we may by the same methods resolve a force ito components — that is, we may find by rules similar to directions, which would be equivalent to the given force. Resultant of Parallel Forces. — Procure two springbalances reading up to 10 or 15 pounds ; also a wooden rod, C D, five feet long and about seven eighths inch square. Drive two nails, E and F, three feet apart and at nearly equal heights, Hang the balances at A and B, from E and F, by cords whose lengths can be readily changed to make up for the stretch of the springs. To determine the resultant of parallel forces in the same and opposite directions, you may perform the following experiments : Fasten the balances to the points G and H of the rod exactly 3 feet apart and about one foot from each end. Adjust the cords until C D is horizontal, and read the balances. This reading, which will be RESULTANTS OF PARALLEL FORCES. 109 ward) is equal to the force (6) in the opposite direction ; and third, the force A is to the force B as the distance L H is to the distance L G — that is, the forces are inversely as their respective perpendicular distances from the opposite force. Try again, using 1C =12 pounds and making L' 6 inches from G, so that L' G : L' H = 1 : 5. You will now find, on making C D horizontal that A reads 10 pounds and B 2 pounds. A + B = 10 + 2 = 12 pounds, the same as K. A : B = 10 : 2 = L' H : L' G, and the forces are parallel. A similar result would be found if the downward force were applied anywhere between the two upward forces. overturn and no equilibrium will be produced. When there is Equilibrium, the resultant of any two of the forces must be equal and opposite to the third. Let us first consider the two upward forces. Their resultant must be equal and opposite to the downward force. Therefore, from the result of the experiment, we may say that— For two parallel forces in the same direction, the resultant is in the same direction and parallel, is in the same plane as the components, and is equal to their sum. Its line of action is nearer the larger force, and its perpendicular distance from the lines of actions of the two forces is inversely as the magnitudes of those forces. Consider the upward force A and the downward force K. The resultant of these must be equal and opposite to B. Note that B is equal to the difference of K and A, and is outside of the line of action of the two forces on the side of the greater force K. Hence — For two parallel forces in opposite directions, the resultant is in the direction of the larger force and is parallel to the components and in the same plane. It is equal to their difference, is outside of the two forces, and on the side of the larger force. ponents. To illustrate : Suppose two men, A and B, to be carrying between them, on a board 6 feet long, a rock weighing 100 pounds. The rock is 2 feet from A. How much weight is each man bearing ? The load Wi on A must be to that W2 on B inversely as their distances from the rock— that is, Wi : W2 - 4 : 2. Hence, W1 : W, + W2 = 4 : 6. But Wi + Wa must be 100 pounds, therefore Wl : 100 = 4 : 6 and Wt = QUESTIONS.— How may forces be represented by lines ? Represent two forces acting at a point A an 1 at an angle of 45° to each other, one of 5 pounds, the other of 8 pounds. How much would be the resultant of these two forces if acting simultaneously, and what would be its direction ? A large rock is to be moved northward ; two horses are attached to it, one of which, A, always pulls 200 pounds, the other, B, 300 pounds. If A pulls south and B north, what will be the resultant pull and in what direction ? If A pulls northeast and B northwest, what will be the amount and direction of the resultant pull ? In what direction must both pull to give the maximum resultant ? How much will that be ? Could they pull in any other directions so as to give a resultant in a northerly direction ? Two men are pulling at opposite ends of a rope, fastened in which is a spring-balance ; A is pulling with a force of 50 pounds. How hard must B pull to prevent the rope from going toward A ? How much will the spring-balance read ? Three men, A, B, and C, are pulling horizontally on ropes knotted at one point as in Fig. 24. A pulls north 20 pounds, B southeast 50 pounds, C southwest 30 pounds. To what single pull would these three simultaneously applied be equivalent ? In what direction and by what amount should C pull just to produce equilibrium against the joint pulls of A and B ? In what direction and by what amount should a fourth man pull just to neutralize the pulls of A, B, and C in the first case ? A man fastens the cord of Fig. 24 to a stake in the ground at C and another at B, and pulls at D horizontally with a force of 20 pounds, the knot being at such a point that A C is northwest, A B northeast, and A D south. What is the pull in A B and in A C ? Draw a diagram in which the angle BAG will be very large, nearly 180°, so that A is nearly in line with B and C, and find the pull in each for a pull of 1 pound at D. (This would be the condition of things in a stretched line with a weight hung about at its middle.) Stretch a clothes-line between two hooks and hang a weight upon it near the middle. Is the pull along the line and on the hooks greater or less than the weight hung on the line ? As the line is more nearly straight with the same weight, is the lengthwise pull greater or less ? A weight of 50 pounds rests on the top of a wooden frame shaped like a letter Y upside down, whose arms are at right angles with each other. How much pressure is transmitted down each arm ? opposite directions. A bridge weighs 100 tons, and its weight is uniformly distributed throughout its length. H ,w much does it press down on each abutment ? Neglecting the weight of the bridge, suppose an engine weighing 30 tons is on the middle of a bridge. How much of the load does each abutment carry ? Suppose the engine is one third of the way from one end of the bridge, how many tons1 pressure due to the engine are there on each abutment ? How many tons due to engine and weight of bridge together ? A man and a boy have to carry together a heavy object of whose weight the man can carry just three fourths and the boy one fourth. If they hang it on a stick between them, at what point on the stick must it be fastened ? Arm of a Force. — Moment. — Sometimes an object is pivoted, so that it can not move bodily onward with respect to what it is attached to, but can only revolve. For instance, a wheel can turn around on its axle, but can not leave the wagon. A force applied to such a pivoted object can merely accelerate its rotation about the pivot. Procure a wooden rod about 2 feet long, 1 inch wide, and half an inch thick. Bore a smooth hole near one end, A (Fig. 28), and put through it an easily-fitting wire nail or screw. Drive this into a block standing out from a vertical surface. At B, connect a spring balance, as shown in the figure, fastening its top by a 112 ACTION OF FORCES. point E. Draw up the cord D until A B is horizontal. Read the balance, and allow for the zero reading. The corrected reading will be found to be 2-£ pounds — that is, just one half W. Call the force exerted by the balance, F ; then we have two forces, F and W, acting at different distances, 0 C and 0 E, from the axis, these distances being measured at right angles to the line of action of the forces. We have seen when 0 C was one half of 0 E that F was one half of W. Make 0 C one third of 0 E, and W 6 pounds. Then you will find, on adjusting and correcting, that F is 2 pounds, or £ W. Put in another nail, to hang the balance so that E will come about half-way along the rod. Adjust the rod horizontally, and take the zero reading as before. Put on the weight W, or 6 pounds, near the end of the rod, so that W will be on the other side of E from 0, and so that 0 C will be twice 0 E. Then you will find F to be 12 pounds— i. e., twice W. You see, then, that in all cases The distance 0 C or 0 E, measured from the axis of rotation perpendicularly to the line of action of the force, is called the Arm of the force, or sometimes the Lever Arm. The product of a force into its arm is called the Moment of the force. Thus, W X 0 C is the moment of the force W with respect to the axis 0, and F X 0 E is the moment of F. A moment is said to be right-handed when it tends to produce rotation in the direction of that of the hands of a clock, and left-handed when the tendency is in the opposite direction. Thus, in the experiment, the moment of W was always right-handed and that of F left-handed. Equilibrium of Moments. — We see, then, that in each case in our experiment there was equilibrium when the righthanded moment (WxO C) was equal to the left-handed moment (FxOE). A body may be acted upon by any number of forces. Take the case where these act in any direction whatever in the same plane or in parallel planes. They will be in equilibrium when the sum of the right-handed moments is equal on page 60. Couples. — If two equal and opposite parallel forces act upon a body, they are called a Couple. We have shown that the resultant of two parallel forces is equal to their difference ; when the forces are equal, their resultant, therefore, is zero. A couple does not tend to move a body as a whole. Let FI and F2, applied at the points a and &, represent a couple. Draw a line c d perpendicular to and joining the lines of action of the two forces. Then c d is called the arm of the couple. The moment of the couple is the product of either force into the arm c d — i. e., moment = Fx x c d = F2 x c d. A couple can not be counterbalanced by any single force, but requires the application of another couple opposite in direction and of equal moment in the same or a parallel plane. FIG. 29. -A COUPLE. small stone, or any dense object, at the end of a strong cord two or three feet long. Swing the stone around the hand so that it revolves, at a nearly uniform speed, in a circle, as A E F G, Fig. 30. You will notice that you are obliged to exert a steady pull or force upon the cord in order to keep the stone from flying away from you. The cord serves merely to transmit this force from your hand to the stone, thus pulling the stone continually toward the hand. by a constant force toward the center of the circle. While the stone is revolving, let go or cut the cord at any instant. The stone will fly off in some direction. What will that direction be 1 Try the experiment several times by swinging the stone in a horizontal circle, just above a smooth floor, and looking down upon it from above. The curved path due to gravity will thus be avoided. Note carefully the direction in which the stone flies off each time. You will see that this is the direction of the straight line tangent to the circle at the point at which the stone was at the moment of release. For instance, if it were at A, Fig. 30, when you let go the cord, it would move off along the straight line A B D, tangent at A. The tangent is the direction of motion of the stone (page 16) at that instant. It is evident that this must be the case, because, after you release the cord, the stone moves off merely by virtue of its inertia, and must, therefore, follow the law of inertia as expressed by Newton's first law of motion (page 31). If, then, the F 3Q body A is revolving uniformly in the circle A E F Gr with such a velocity that it would pass from A to E along the circle in a given time, it would, if released at A, pass along the straight line A D with the same velocity, reaching a point B such that A B = A E in that time. An object thus revolving, therefore, tends to fly off at a tangent, and with the same velocity that it is moving along its path. Every point beyond A of the tangent A B D is farther from the center than the circle itself. Hence we may say that the object tends to fly away from the center ; but notice that it does not tend to fly off radially. This tendency may be called the Centrifugal (flying from the center) Tendency. The force required to keep the body in its circular path is called the Centripetal (center -seeking) or Central Force. Give the cord a certain length, perhaps six inches. Whirl the stone twice a second. Notice the pull (central force) which you give. Then whirl the stone twice as fast — that is, four times a second. Notice that the central force required is much greater. In fact, with double the number of turns, the force required is four times as great ; with treble the number, nine times, etc. The central force is, therefore, proportional to the square of the number of turns per unit of time, the radius remaining the same. Now make the radius twice as great and turn, as at first, twice a second. The central force required will be twice as great. If the radius be made three times as great, the CENTRAL FORCE. 115 force will be three times that exerted at first. The central force is, therefore, directly proportional to the radius of the circle, the number of turns remaining the same. Compare the pull required for two stones, one of twice the mass of the other, but whirled in circles of equal radii and at the same rate. The central force will be found proportional to the mass. The velocity of the body in the orbit being uniform, the central force is doing no work. Its effect is merely continually to change the direction of motion of the body. The centrifugal tendency of the body is erroneously called " centrifugal force." It is not, however, a force at all. The only force exerted is the centripetal or central force, which is of such an amount as to change the direction of the momentum just fast enough to keep the body moving in the circle. When you are whirling a stone in a vertical circle, you will notice that the pull is greater 'when the stone is at the bottom of its path and less when it is at the top. This is because at the bottom you have to exert the central force plus the weight of the stone, and at the top only the central force minus the weight. If the stone is revolving at such a rate that the central force is less than the weight, then it will not rise to the top of the circle, but will go up part way and fall, as you can see by making the stone whirl fast and then allowing it to slow down by the resistance of the air. Every Revolving Object affords an Example of Central Force and centrifugal tendency. The grandest illustration to be found is in the motions of astronomical bodies. The moon revolves around the earth in a nearly circular orbit, and is held in that orbit by a central force, which we are next to study under Gravitation. Similarly, the earth and all the planets revolve in orbits about the sun, the central force again being gravitation. If gravitation were to cease, all the heavenly bodies would move off in straight lines, and the entire order of the universe would be changed. As the earth, a wheel, or any object, revolves upon its axis, every particle of matter in it tends to fly off at a tangent. To prevent this motion, some force — cohesion, gravitation, etc. — must be exerted. You know how mud flies from a rapidly turning carriage-wheel. This is because the force of adhesion of the drops to the wheel is not great enough to overcome the centrifugal tendency, or, in other words, to change the direction of the momentum of the drops fast enough to keep them against the surface of the wheel. Objects resting upon the surface of the earth are held in place by their weight, although, owing to. the revolution of the earth upon its axis, they have a centrifugal tendency. But if the earth were to revolve about seventeen times as fast as it now does, objects at the equator would have a centrifugal tendency equal to their weight, and would fly off at a tangent. A grindstone, revolving rapidly, throws off water from its wet surface for a similar reason. If the stone be revolving very fast, the centrifugal tendency of its outer portion may become greater than its cohesion can withstand, so that it will fly asunder, its parts moving off with great energy. Large stones bursting in this way may do much damage ; and heavy fly-wheels of engines, or other parts of machinery which revolve at high speed, must be carefully designed, so that they may be strong enough to resist the centrifugal tendency. that it will hang upright. Partly fill it with water. Twist the cord around several times and then let it untwist, twirling the tumbler. Notice how the water moves outward, piling up at the side of the tumbler, and even flying out over the edges if the twirling is fast enough. What does this illustrate ? Whirl the apparatus shown in Fig. 31. Notice how the hoops bulge at the equator, being drawn in at the poles. How is this owing to centrifugal tendency ? Why is the action more pronounced at higher from flattening out entirely? suppose the earth were slightly fluid or pasty, and were revolving on its axis as it now does, what form would it take? Why? The earth CENTRIFUGAL TENDENCY. actually has such a form, and doubtless from the action of this cause when it was in a less rigid condition than no\y. Why is the centrifugal tendency greater at the earth's equator than at the poles'? This fact enables us to account for the difference of weight of a given body at various parts of the earth's surface. At the equator, the body has the greatest centrifugal tendency, and is also farthest from the earth's center ; its weight from both of these causes is less than elsewhere on the earth. At the poles it would be nearest to the center and would have the least (in fact no) centrifugal tendency. Its weight would, therefore, here be the greatest. At intermediate latitudes, the weight would be between these two extremes. When a railroad train is going round a curve, the centrifugal tendency must in some way be neutralized. To do this, the outer rail is raised higher than the inner one. The weight of the cars (acting through their center of mass) may then be resolved into two components, one perpendicular to the inclined bed of the track and simply pressing the train against the track, the other horizontal and toward the inside of the curve. ' The latter will then give the necessary central force. The tangential component will differ in amount with the speed of the car, so the track can not be laid to suit all speeds ; it is designed only for the greatest speeds. You will, therefore, not feel the tipping on the curve in a fast-running train, while you will notice it on the same curve in a slow train. Why does a bicycle-rider, in going rapidly round a curve, lean toward the inside of the curve? QUESTIONS. — If, in the apparatus of Fig. 28, W is made 10 pounds, and is one fifth of the way from O to E, what will the balance read ? Reverse the positions of balance and W, and what will the former read ? A force of 6 pounds acts on a pivoted body at such a point that the perpendicular distance from the pivot to the line of action of the force is 3 feet ; what is the moment of the force ? What is meant by right-handed and left-handed moment ? Suppose the moment in the preceding problem were right-handed, how much would be the magnitude of the moment required to counterbalance it ? What must be its direction ? If its arm were 9 feet, what must be the amount of the force ? Draw various diagrams representing a pair of forces whose moments are counterbalanced. A boy weighing 50 pounds sits on one end of a board placed across a log, and another boy weighing 100 pounds sits on the other part of the board ; how far out from the log must the second boy sit to balance the first ? How much will be the downward pressure upon the log ? What kind of a force is necessary to keep an object revolving uniformly in a circle ? In what direction does such an object tend to fly off if that force ceases ? Why ? Why may this tendency be called a centrifugal tendency ? Why is it better called a tangential tendency ? Why should it not be called a centrifugal force ? What is meant by central force ? By centripetal force ? What does this force do ? Does it perform any work on an object revolving in a circular orbit? Why? Why does the weight of a body differ at different points of the earth's surface ? If a standard pound-weight and a weighed pound of shot were exactly balanced at Chicago, would they cease to balance each other if transferred to Quito ? If you should buy a quantity of nails in the city of Mexico that would weigh exactly a pound on a spring-balance, would they weigh more or less than a pound on the same balance at Hammertest in Norway ? Why ? drawn by two horses on opposite sides of a canal. Illustrate in a similar manner the resultant in the case of the onward motion of a swimmer striking the water with both hands ; the darting of a trout in a straight line by the action of two pectoral fins. Of what tendency is advantage taken in discharging a stone from a sling ? Have you read of instances in history where sufficient velocity was in this way communicated to projectiles to render the sling a formidable weapon ? There is a legend that in an exhibition of skill Richard the Lion-hearted severed an iron bar with his sword, while Saladin surprised his opponent by cutting a feather pillow in halves with his scimiter. Explain the principles which made these feats possible. On the top of one of the fingers of your left hand, balance a card with a penny placed upon it ; strike the card suddenly with the middle finger of the right hand, when it will fly away and the penny remain on the finger. Why ? Suppose that a leader of silk-worm gut will just pull out a spring-balance to the 6-pound notch without breaking. How much strain will it bear from the angler and from the salmon when they are pulling at cross-purposes ? Each of the chain of bones forming your spine is separated from its neighbors by disks of elastic tissue. What happens, then, when you jump heavily on your feet from a height ? Is the brain seriously jarred ? Can you think of a reason why a man is a little taller in the morning than at night ? Why you should not form the habit of sleeping on a high pillow ? Enumerate all the forces acting upon a ball thrown into the air. As its velocity diminishes, what is its direction ? Why is it found necessary to elevate a rifle in order that the bullet may strike a distant target ? FORCE OF GRAVITATION. 119 Suppose a vessel steaming at the rate of 12 miles an hour to be ascending a river the velocity of whose current is 2J miles an hour ; at what rate will it progress ? What will be its speed in descending the same river ? A locomotive weighing 20 tons moves with a velocity of 40 feet a second. Another locomotive weighing 25 tons moves at the rate of 4,800 feet in a minute. How do their velocities compare ? How do they compare in momentum ? UNI VERSAL GRA VITA TION. Every Particle of Matter tends to approach every other Particle ; or, in other words, any two particles of matter whatever will be accelerated toward each other unless such motion is prevented. There appears, therefore, to be some form of energy which causes a universal force of attraction. This force is called Universal Gravitation. The nature of the energy causing it is unknown. The law which expresses the action of the force of gravitation was first stated by Newton, and is as follows : is that of the straight line joining them. 3. The magnitude of the force is directly proportional to the product of the masses of the two particles, and inversely proportional to the square of their distance apart. A Homogeneous Spherical Body, with reference to any body outside itself, acts as if all its mass were concentrated at its center. Thus, two spheres of uniform material attract each other with a force proportional to the product There is reason to suppose that if a new mass of matter could be created suddenly in space, its attraction would be felt in an imperceptibly short time on every existing particle of matter, at least within the limits of the visible universe. Gravitation between two Bodies is not affected by interposing any other Body. — When the moon, for instance, passes into the shadow of the earth and is eclipsed, the earth is directly between the moon and the sun ; but the attraction between the moon and sun is apparently not in the least diminished or increased in consequence. A body weighed in the air shows no apparent change in weight by placing other objects between it and the earth, the very minute increase due to the attraction between such objects and the body being imperceptible. The energy which produces universal gravitation is the source of the immense forces necessary to keep the planets in their orbits around the sun, and, indeed, to hold together the whole astronomical system. Some idea of the amount of the force of attraction due to gravitation may be obtained from the statement that two homogeneous spheres, each having the mass of one ton and at a distance of 10 feet between centers, would attract each other with a force of only a little more than a millionth of the weight of a pound ; whereas, the force of attraction between the moon and the earth is equal to the weight (at the earth's surface) of twenty quadrillion tons. The weight of the moon's mass at the earth's surface would be about 3,600 times as great as this. The forces exerted among astronomical bodies are inconceivably immense only because the masses of these bodies are so vast ; but, owing to the great distances between the bodies, the forces are small as compared with the weight of equal masses at the earth's surface. It was from the mathematical laws governing the motions of the planets, the forms and sizes of their orbits, and their times of revolution in these orbits, that Newton deduced the Law of Gravitation. weight acts toward its center. A cord, by which any body is suspended — e. g., a plumb-line — will then be always vertical— that is, will point toward the center of the earth. This statement, however, is not strictly true. A plumb-line at the foot of a mountain will not hang precisely vertical ; but its lower end will incline a little toward the mountain because the mass of the bob will be sensibly attracted sidewise by that of the mountain. The amount of this inclination is very slight, but has been indirectly measured. Bodies become lighter as they are taken up from the earth's surface ; but since the force diminishes as the square of the distance from the center (not from the surface) of the earth, and as the center is 4,000 miles below the surface, the diminution is small. F A body weighing 1,000 pounds at the earth's surface would weigh (on a spring-balance graduated at the surface) only one pound less at a height of two miles. At the distance of the moon from the earth (240,000 miles), the same body would weigh less than five ounces. 2 x 4ooo}-j-ib. A body below the surface of the earth weighs less than at the surface because some of the mass of the earth is now attracting upward. At the center of the earth the body would have no weight. For example, a body at P (Fig. 32) would have above it all that portion of the earth included between the plane A P' B and the surface A P B. This portion would be attracting it upward— i. e., toward the surface — while the rest would be pulling it downward— i. e., toward the center. The resulting downward pull would be the difference between these two. At the center, the portions on opposite sides of any plane would be equal. 122 GRAVITATION AND THE PENDULUM. be required to give it the same acceleration ; but the weight is proportional to the mass, and the weight is the force causing the fall. Hence the body of twice the mass has twice the force (weight) acting upon it, and therefore moves with the same acceleration. The size, shape, and material, make no difference, for the acceleration of a free body is determined only by its mass and the acting force. But bodies falling through air are not entirely free, for the air offers a resistance tending to retard their motion. This resistance is due partly to friction, partly to the work necessary to displace the air in front of the moving body. Its amount is greater the faster the body moves, the larger the body is in proportion to the mass, and the more irregular its shape. Thus some objects, such as the seeds of dandelions and thistles, or feathers, wool, fine dust, a spread umbrella point upward, fall very slowly through air, while bodies of equal mass in compact form would fall much faster. This may be illustrated by an experiment with the " guinea and feather tube " (Fig. 33), a long glass tube containing a coin and a feather or bit of paper. Invert the tube, and you will see the metal drop quickly to the bottom while the feather falls slowly, just as they would act in the . ar outside. Connect the tube with the air-pump and exhaust part of the air. The metal will still fall faster on inverting the tube, but the feather less slowly than before. Pump out all the air possible. The feather will now fall nearly or quite as fast as the metal. If you could remove all the air, they would fall equally fast, and both would fall slightly faster than the metal did through the air. Free Falling Bodies move with Uniformly Accelerated Motion. — This fact has been established by careful .measurements, and yet the statement is not strictly true. Uniform acceleration can be produced only by a constant force, and the weight of bodies increases slightly as ever, within vertical distances of a few thousand feet. Falling bodies, therefore, afford a special example of uniformly accelerated motion, and must follow the laws given on page 20. The rate of acceleration at places not far from latitude 45° and not more than a mile above sea-level, is about 980 centimetres or 32-2 (roughly 32) feet per second. This is the quantity a in the formulae, and is often denoted by g. 0 wing to the resistance of the air, results calculated by these laws for bodies falling in air will be inexact. If a stone falls in air, it will meet with a continually increasing resistance. After it has fallen a few hundred feet, this resistance will become equal to its weight, so that the body will cease to be accelerated and will fall at a uniform speed. Projectiles. — A bullet discharged from a gun, an arrow from a bow, a stone thrown by the hand, are examples of Projectiles. The figures on pages 55 and 56 show the paths which projectiles would take on being discharged at various angles to the horizontal, provided no resistance were offered by the atmosphere. The path A B' C' would be in any case a portion of a curve called a parab'ola. It may be shown mathematically that the horizontal distance A I', which a projectile would traverse before coming to the ground, if started with a given velocity, will be greatest when the initial direction A B is at an angle of 45° to the horizontal. If fired at a greater or less angle, the projectile would reach the ground sooner. The actual best angle is somewhat less, owing to the resistance of the air. In whatever direction the projectile is thrown, the air continuously retards its motion. Thus, if it. were not for air resistance, a body thrown upward would have the same velocity on reaching the earth as at starting ; but the air continuously slows its speed, so that it rises less high and strikes the ground with less velocity than it otherwise would. QUESTIONS. — Wliat is Universal Gravitation ? To what form of energy is it due ? State the law of gravitation. In reckoning the attraction of a sphere, at what point may we consider its mass as concentrated ? How much time does it require for gravitation to act between sun and earth ? Is gravitation affected by interposing objects between the attracting particles ? What is meant by the term Weight ? In what direction does weight act ? At what rate does weight diminish as we ascend from the earth's surface ? A man who learned that weight diminishes as the square of the distance, proposed that soldiers should carry their knapsacks supported on the muzzles of their muskets, as the knapsacks would then be about twice as far from the ground and would therefore weigh but one fourth as much. Where was his fallacy ? Why does weight diminish as we descend into the earth ? What do we mean by " up " with reference to gravity ? At the bottom of a mine 1,000 feet deep, how much would the mass of a pound weigh ? How much at a height of 1,000 feet above the surface ? Does weight diminish more rapidly in descending into the earth or in rising above it ? What would be the weight of a body at the center of the earth ? What would be its mass ? Does weight have anything to do with producing the mass of a body ? Does mass have anything to do with producing the weight of a body ? With what kind of motion do free bodies fall toward the earth ? What kind of force is necessary to produce uniformly accelerated motion ? Is it then strictly true that the motion of freely-falling bodies is uniformly accelerated ? Why does it appear true in our ordinary experiments ? If a body were to fall toward the earth (in a vacuum), would its rate of acceleration slightly increase or slightly diminish ? Why ? If a body were falling down the shaft of a mine (in a vacuum), what would be the change in its rate of acceleration ? What is the effect of air upon the motion of falling bodies ? What is meant by a projectile ? Why do projectiles near the earth's surface not travel in straight lines ? If a projectile were moving in free space at such a distance from all bodies that gravitation was insensible, in what path would it move ? Why ? In the following problems, the resistance of the air is to be disregarded unless otherwise stated : In a freely-falling body what would be the velocity after 3 seconds ? How long would it take a body to acquire a velocity of 3,220 feet a second ? How far will a body fall in one second ? In two seconds ? In three ? In four ? How far does it fall during the first second ? During the next ? During the third ? The fourth ? How long will it take a body to fall 100 feet ? A stone is dropped or thrown horizontally from the top of a cliff and reaches the bottom in 3'5 seconds. How high is the cliff ? A stone is thrown vertically upward with a velocity of 50 feet a second. How high will it rise ? How long will it remain in the air ? Does the resistance of the air arrest or oppose gravity in the case of projectiles ? Can you think of a reason why wind-gauges are used on rifles ? If a '44-inch caliber bullet were discharged vertically upward from a Winchester rifle, would it gather sufficient energy in its descent to strike with fatal effect ? Would a charge of swan-shot ? Why ? Can you conceive how the laws relating to projectiles are taken advantage of in military science ? homogeneous spherical particles of any size and mass. Suppose them to be connected by a rigid rod, which for convenience we will assume to have no mass. Let the lines resultant from each will be such that Wj X a c = W2 X b c — that is, so that a c : b c = W2 : W^ For example, if Wl =1, and W8 = 3, then # c : # e = 3 : 1, OT a c must be three times b c. If a b is not horizontal, then let Fig. 35 represent any other position. Now, R must always be parallel to Wt and W2, and at such a distance that Wl X a c = W2 X b c — that is, If, therefore, a force equal and opposite to R were applied at c, it would counterbalance the weight of A and B and hold up the system just as if all the mass, and therefore all the weight, were concentrated at c. The point c is called the Center of Mass, being the middle point of the mass of the body. It is also known If instead of two particles there were three, we should proceed in a similar manner to find the resultant of the three weights in one position of the system, then in another, and so on ; and the intersection of all these resultants would be the center of mass of the system. Bodies are merely collections of particles. Hence The Center of Mass (of Gravity, or of Weight] of a body is the common point through which the resultant of the weight of all its parts passes, whatever the position of the body. On consideration, you will see that the center of mass of a body is in general not at what we should call the middle of the body— that is, at the center of its volume— unless the body is homogeneous. A circle of wood, if homogeneous, would have its center of mass at its geometrical center ; but if a plug of lead were put into it at a (see Fig. 36), the center of mass would be at some position c', between c and a. EQUILIBRIUM OF BODIES IN RESPECT TO WEIGHT. A Body is said to be in Equilibrium with respect to its weight when, on being left to itself, motion does not ensue. Let A (Fig. 37) be any body supported on a pivot always come to rest with its center of gravity c vertically under #, as shown in the figure : for, suppose it pulled to one side, so that c is at c' ; then the weight "W will have a moment Wx«' V, EQUILIBRIUM OF SUSPENDED BODIES. The body then can remain at rest when left to itself — that is, can be in equilibrium (in respect to weight) only when the center of mass is vertically above or below the point of support. This is true of all pivoted bodies. the cord be put in at the proper place, the point of P will also be vertically below the supporting point. Such an arrangement is used by surveyors and others for obtaining vertical lines, and is called a plummet or plumb-line, because the body P is sometimes made of lead (Latin, plumbum) on account of the great density of that metal. The line itself is necessarily vertical, whatever the bob be made of, and whatever its shape. find experimentally the position of this center. Let the body be hung successively, from several different parts. Notice the direction of the suspending cords relatively to the body. These directions will all intersect at one point, which will be the desired center of mass. substance. Mark with a pencil two points on the cardboard just behind the plumb-line, and draw a straight line through them. Do the same for one or more other holes, b, e, etc. These lines (dotted) will intersect at or near the same point, c, which is the desired center of mass — for the center of mass must lie in each line, and therefore at the intersection. Balance a fork, cane, or tion of verticals through the hand for different positions of the object. Stable and Unstable Equilibrium. — If, in Figs. 37 to 40, c be vertically below #, then, on pulling c to one side, the weight will tend to drag the body back to its position of rest. This condition is called one of stable equilibrium. In general, equilibrium is said to be stable when, on being moved, the body tends to return to its original position. If c be vertically above #, then, on the slightest motion, the weight tends to tip the body still farther. This condition is called one of unstable equilibrium. In general, equilibrium is unstable when, on being moved, the body tends to depart still farther from its original position. In the case of a suspended body it is difficult, if not impossible (unless position of unstable equilibrium. Neutral or Indifferent Equilibrium. — If the point of suspension a coincides with the center of mass c, then the body will remain in any position in which it is placed, because the weight always acts directly through the supporting point, and its moment must always be zero. This condition is called neutral or indifferent equilibrium. It is the condition in which the body, on being moved, tends neither to return to, nor to move farther from, its original position. any body, A, is resting on a surface at only one point, #, and c be its center of mass, as in Fig. 41, then it is evident that A is not in equilibrium, and can only be so when c is directly over a. Its equilibrium will then also be unstable. If the body is a spherical one, or a circular one standing on edge on a horizontal surface (Fig. 42), c will necessarily be always vertically over «, and the body will be always in neutral equilibrium. A sphere or vertical circle on an inclined surface can never be in equilibrium, because c can not be over a. Any body whatever (Fig. 4:2) on an inclined surface will be in equilibrium The Base. — Bodies standing by themselves are ordinarily supported by three or more points. A three-legged stool rests upon the floor at the points a, #, and e, Draw lines a #, b e, e a. The surface a b e inclosed by these lines is called the Base. If the body rests at several points, the base is the surface inclosed by the lines circumscribing those points. For instance, if a body rests . on the points abed a cfg I A body is in stable equilibrium only when the vertical through the center of mass passes through the base. As soon as the vertical falls outside the base, the equilibrium ceases and the body overturns. The Degree of Stability depends on the work necessary to overturn the body — that is, to destroy its stability. Let A and B, Fig. 45, represent the same body lying on its side and standing on end. Its degree of stability is greater in the former than in the latter position. Why? Because to overturn it, more work must be done. What is the work to be done I Take the first position A. To destroy the equilibrium, we must bring c up to such a point c' that the vertical c' d falls just beyond b. This requires that the whole mass of the body be raised. We must do work, therefore, against the weight of the body, and, as the weight may be considered as acting through the center of mass, the amount of work done will be the product of the weight into the vertical distance d c', through which the body has been raised. In the position represented in B, the weight is the same, but If the body C is of the same weight as A, and has the same size and shape of base, but is of such a shape or density that its center of mass is much higher, then it will be less stable — for the height d" c' will be less, and the work done correspondingly less. Of two bodies with the same base and center of mass at the same height, but of different weights, the heavier will be the more stable, because the work required to overturn it, being the product of the weight into d c', will be greater. To determine, then, which of several bodies or of several different positions of the same body is the most stable, we must ascertain which requires the greatest work to be done in order to destroy the equilibrium by overturning the body. If it is desired to have any Object or Structure stable, it is necessary to see that the center of gravity shall be over the base. To secure the greatest degree of stability possible, care must be taken to arrange matters so that the amount of work required to overturn the object shall be as great as possible. This is usually accomplished by making the base large and the center of mass low. QUESTIONS.— Define center of mass ; center of weight ; center of gravity. Why are the center of mass and the center of weight at the same point ? Suppose two particles, of mass 5 and 1 respectively, to be connected by a rigid rod of length 10 and without weight — show where their center of mass is located. Are the center of mass and the geometrical center of bodies generally the same ? Why ? When is a body said to be in equilibrium with respect to its weight ? If a body is suspended so that it can turn about a point, what is the condition for equilibrium ? If a body is suspended by a flexible cord, what will be the direction of the cord when there is equilibrium ? Why ? method. Suppose that you wished to find the center of gravity of a bat, how could you do so by laying it across the edge of a board ? What are the three kinds of equilibrium ? Describe each. Give examples of each. If a body rests upon several points, what constitutes its base ? What is the condition of stable equilibrium for such a body ? Why does a man lean forward when carrying a heavy load upon his back ? If you have a heavy weight in one hand, what position do you take ? Why ? Why does a load of hay tip over so easily if on a side-hill ? A^coach with heavy baggage piled on top, on a rough road ? What do we mean by saying that a thing is top-heavy ? Why does a ball placed on a sloping surface begin to roll, while a cube maintains its position ? Suppose that a tall tower leans to one side, how much may it lean before it will fall over of its own weight ? (Read about the famous leaning tower of Pisa, and of Galileo's experiments there with falling bodies.) Upon what does the degree of stability of a body depend ? Why does a man place his feet well apart when he wishes to plant himself very firmly ? Where is the center of gravity in the body of a man ? Why does he turn his toes out ? Why use a staff when he is old ? Why can not a person with his heels against the wall stoop without falling ? Two blocks of wood of equal weight have their centers of mass at equal height ; one is shaped like a pyramid and stands on its base, the other is a cube ; which is the more stable ? Why ? A certain wagon is loaded at one time with a ton of iron, at another time with a ton of hay ; in which condition is it the more stable ? What are common ways of making bodies stable ? Press the head of a needle firmly into the end of a cork, and stick into opposite sides of the cork two forks sloping downward at equal angles. The whole may now be balanced upon the needle's point. Why ? THE PENDULUM. The Simple Pendulum. — Suspend a stone, or any heavy object, A, from a firm support, Fig. 46. Pull it an inch or two to one side and let it go. It will swing to and fro for a long time. Any object oscillating thus upon a pivot or axis of suspension, by its weight, is properly called a Pendulum ; but the term is generally used to refer to small, heavy objects hung by a light suspending cord or wire. As the pendulum descends from either extreme of its swing, it gains velocity and therefore energy, which it loses again on its upward swing (page 36), and which is greatest at the lowest or middle point. If energy can neither be created nor destroyed, whence comes this energy, and where does it go, the effects of resistance being neglected ? Its source is the energy of gravitation ; and in losing energy, the pendulum merely restores energy to that source. The process, then, is a periodic receiving and giving back of energy between the stock of gravitational energy and the pendulum. To express the idea in an- LAWS OF THE PENDULUM. 133 other way, the pendulum has at the extreme of its path a certain potential energy due to its weight and its position, and this potential energy is converted gradually into actual (or kinetic) energy in the descent, and reconverted into potential energy in the ascent. Consider carefully what is meant by potential energy, and you will see that the two forms of statement are equivalent. The simplest possible pendulum would be a material particle hung by a cord without weight. The nearest practicable approach to this is a small, heavy sphere hung by a very light cord or wire. A lead or brass ball suspended by a braided silk cord works best, but small stones hung on twine will answer the purpose. By the length of a pendulum is meant the distance from the point of suspension to the center of oscillation. For the simple pendulum, the center of mass may be taken as the center of oscillation. These laws will be partly illustrated by experiment. EXPERIMENTS WITH THE PENDULUM. — Hang up a stone or a metal sphere B by a cord, so that the length of the pendulum (from b tc center of mass of B) is the same as that of A, as nearly as you can judge. Hold B aside as at k, and at the beginning of a minute by a watch or clock let it go. Count one when it reaches Z, two when it gets back to k, three at I again, and so on. Just as one hundred is counted, note the number of seconds that have elapsed. This, divided by 100, will give the " time of a single vibration," or swing of B. Pull A and B aside and let them go at the same instant. You will find that they will keep pace with each other almost perfectly. They have, therefore, the same rate or time of swing. Make another pendulum C out of a wooden block, hollow tennisball, or any other substance, adjusting its length as nearly as possible to equal that of B. Start A, B, and C, swinging at the same instant. They will keep pace very closely, the slight difference you may observe being due to the fact that the lengths are not exactly equal. These two experiments show that the time of vibration of pendulums of the same length does not depend on the material of the bob. ment of time. It was first noticed by Galileo, who observed that the great chandelier in the cathedral of Pisa swung in equal times without regard to the amplitudes of the swing. Hang a fourth pendulum, D, of a length equal to one fourth that of B. Set B and D swinging at the same instant. You will see that D makes two swings to one of B. The time of one swing of B, then, is twice that of D. The length of B is four times that of D. Therefore, the time of B : time of D = 2 : 1. But 2:1 = square root 4 : square of 1. Hence the times of vibration of pendulums of different lengths are proportional to the square roots of their lengths. Vary the length of B until its time of swing is just one second. Measure as carefully as you can the distance from the point of support to the center of mass of B. It will be a little less than a metre — i. e., about 39 inches. At latitude 45°, sea-level, the length of the seconds pendulum is '99356 metre = 39-117 inches. The time of vibration would be less at a place where the force of gravity is greater, because the accelerating force (weight) would be greater for the same mass in the pendulum, which would, therefore, move faster. The pendulum thus affords the most accurate means of determining the value of g in different places. Application of the Pendulum to Clocks. — The isochronism of the pendulum is utililized in the measurement of time — in subdividing the astronomical unit of time, the day, into hours, minutes, and seconds. Fig. 47 shows the essential parts of the mechanism for this application, and when the following description is studied, some pendulum-clock should be examined by the pupil. The function of the pendulum is solely to regulate the rate of motion of the works, so that the wheels (which carry the hands indicating the time) shall turn at exactly the proper and constant rate. The source of energy maintaining the motion of a clock is usually elasticity acting by a coiled spring, or gravity acting through " weights " hung on a cord wound over an axle. The work which this energy has to perform is to move the clock-works against their friction, and to keep up the motion of the pendulum, which would otherwise grad- FlG 47<_EsCAPEMENT OF ually come to rest. Why ? CLOCK. wheel, shown at D E and D' E' (Figs. 47 and 48), and pivoted at F. Let us suppose that this wheel tends thus to rotate right-handedlyc A C B is a curved piece of metal called the pallet, having at each end, A and B, a tooth or projecting point. It is fastened at C' to the spindle A' H', which is pivoted at both ends, and to this is also attached the bent rod or wire H' G' G, called the crutch. This whole mechanism is the escapement. The pendulum P hangs from a fixed point I', its upper part being composed of a thin flexible metal strip, I' J', and it passes through the crutch at G G'. Let us follow the action, starting with the position shown in Fig. 47. A tooth of the scape-wheel is pressing against the pallet-tooth at B, owing to the pressure of the spring or weights, and the wheel is thus held from moving. The pallet-tooth A is free of the wheel; The crutch and pendulum are at one extreme of the swing, and will therefore now begin to swing back. When the pendulum becomes about vertical, the pallet will have turned so that its end A will have descended into the space between two teeth at E, and the end B will have risen just enough to release the scapewheel tooth. The scape-wheel will, therefore, jump forward until the following tooth strikes the pallet at A, advancing thus by about the space of half a tooth. The pendulum, continuing its swing, will reach its right-hand extreme, and will then turn and swing back, the pallet at A presently releasing the scapewheel, which then advances another half-tooth until stopped by the pallet at B. This process goes on continuously, the scape-wheel advancing a whole tooth for each double-swing of the pendulum. The energy necessary to overcome air resistance, etc., and thus to maintain the pendulum in motion when once started, is supplied to it from the scape-wheel through the pallet and crutch. Start again with the first position of Fig. 48. The wheel is then pushing up the pallet at B', owing to its pressure on the sloping pallet surface, and this, of course, pushes the crutch, and the crutch in turn the pendulum, to the right, adding to their energy. Such action continues until the pallet releases at B' and engages at A'. From the right-hand end of the swing downward, the wheel similarly pushes upward the end A' of the pallet. The Balance-Wheel replaces the pendulum in watches and some clocks. It consists of a pivoted wheel which swings to and fro on its axis in equal times, owing to the elasticity of a spring attached to it. QUESTIONS. —What is a pendulum ? What is meant by a simple pendulum ? What maintains the motion of the pendulum ? What causes it to come gradually to rest ? What is meant by the length of a pendulum ? State the laws of the pendulum. Show how to demonstrate these laws by experiment. What is meant by the isochronisni of the pendulum ? What is the length of a pendulum beating seconds ? Beating half -seconds ? Beating quarter-seconds ? How may the pendulum be used to measure the variations in weight at different parts of the earth's surface ? Explain the application of the pendulum to clocks. Can you explain the object of feathering your oars while rowing ? How is our earth kept in its path about the sun ? In the latitude of New York, a seconds pendulum is about 39 inches long. How Would a plumb-line on a ship's deck under the rock of Gibraltar hang perpendicularly ? Why ? Could you easily detect the variation ? Is there a place between the moon and the earth where a body would have no Why does the mud fly off from the felly and not from the hub ? How can you determine whether a wall is exactly vertical ? Why is your student's lamp made so heavy at the base ? Two pendulums at Jacksonville, Fla., vibrate in 40 seconds and 10 seconds. How NATURE AND LAWS OF FRICTION. Friction opposes Motion. — Draw your hand across any surface, push a pile of books along the table-top or a chair across the floor — in short, cause any two solid surfaces to rub together ; you will find that to keep up continuous motion you must do work. This is true even if a uniform velocity is maintained, in which case the object is not storing up or giving out kinetic energy. You are moving the body uniformly against a resistance. This resistance is at the rubbing surfaces, and is called Friction. What is the nature of frictional resistance, and what becomes of the energy used up in doing work against friction ? The second question has been answered by showing (page 40) that the rubbing surfaces become hot. The energy is transformed into heat. Of the nature of the resistance caused by friction, we may form an idea in the following way : No surface is perfectly smooth. Even polished surfaces, when viewed through a glass, appear scratched or uneven. The irregular lines abed (Pig. 49) may represent a magnified section of the smooth, rubbing surfaces of two bodies, A and B. Notice how the irregularities of these surfaces interlock. Thus, at a, &, and d, for instance, when moving over B in the direction of the arrow, A would experience a resistance owing to the backward elastic pressure of the energy of these constitutes the heat produced by the rubbing. It is thus not difficult to conceive how the resistance of friction is due to the interlocking of roughnesses of surface. If the smoothness of the surface could be made perfect, two clean rubbing surfaces of the same substance would not differ from two parts of the same body separated merely by an imaginary plane. The only interlocking then would be due to the vibration of the molecules across that surface, which of itself would be enough to cause very great friction. Laws of Sliding Friction. — Let A (Fig. 50) be a block of well-planed wood 2 by 4 by 8 inches, sliding on a smooth horizontal board C. Let B be a pulley turning with little friction, over which runs a cord attached to A at E and carrying a pan for weights below. A spiral spring fastened to the table and by a cord to the pan checks the descent of the latter somewhat gently, and thus prevents the spilling of the weights. Put sand or shot into the pan until, on tapping the block A with the finger, it will start and keep up its motion, but not be accelerated. Note the weight of pan and contents together and call it w\ ; also the weight of the block, and call it W^ Then wl is called the amount of " friction of motion " of A upon C under the pressure Wj. EXPERIMENTS. — The amount of this friction depends on the amount of the pressure WL Put a weight upon A so that the pressure is doubled — i. e., is 2 Wx. Increase the load in the pan until motion is again just kept up. On weighing the pan and contents, you will now find it very nearly 2 w^ If you make the pressure 3 Wlt the pan-load will be found 3 wlt and so on. Hence, the friction of motion etc. These coefficients enable one to find what the friction would be for a given pressure between the surfaces. They are approximately constant for any given substances. The friction is often stated to be independent of the speed at which the surfaces are moving on each other. This is by no means generally true, but for some substances is nearly so where the speeds change but little from a given amount. All three of the above laws are only rough approximations. Friction varies so greatly, with slight differences of condition of the surfaces, that measurement of it appears inexact and unsatisfactory. Friction of Repose. — Adjust the load in the pan until it is just sufficient to start A from a state of rest. You will then find it decidedly greater than that necessary to maintain motion. Here we have the Friction of Repose, or, more and many other conditions. Friction of Gases and Liquids. — Lay a clean plate of glass on the table. Place upon it another plate of about the same size. Press the two firmly together for a moment. Then let go, and slide the upper plate over the lower by pushing horizontally against the edge with your finger. Bear in mind how hard you have to push. Lift off the upper plate, lay it gently down again on the under plate, and immediately slide it by a side push. Note how much more easily it slides. This is because the glass surfaces are not so nearly in contact as before, but are kept apart by the film of air between them ; and the friction is that of the layers of air parallel to the plates moving over each other. Such friction is much smaller in amount than the solid-surface friction. When the upper plate settles down by its weight, forcing the air out, the friction increases. Remove the upper plate, and apply a layer of water or oil to the lower one. Put the plate on again lightly, and notice how easily it slides. Here the friction is that of layers of water or oil parallel to the plates. The friction of some liquids is less than that of others, and the same is true for gases ; in all cases, it varies with temperature. The use of oil for greasing or "lubricating" rubbing surfaces (axles, bearings, etc.) is familiar to you, and is simply a process of making the lesser friction of the oil or other lubricant replace the greater friction of the dry surfaces. The object is to avoid the injury to the surfaces by the grinding and polishing of the dry rubbing, and also to do away with the waste of energy required to overcome such friction. QUESTIONS. — Give examples of friction. Show what the nature of frictional resistance is. Into what form is the energy used in overcoming friction changed ? Explain how this transformation is made. If rubbing surfaces could be made perfectly smooth, would there be any friction ? Why ? State the laws of sliding friction. Describe a method of proving each. Is friction independent of the speed of motion ? How may the friction of gases and of liquids be experimentally illustrated ? Explain the action of oil and other lubricants. What is their object ? Mechanics, in the strict sense of the word, is the Science of Machines and the art of constructing them. It is quite common, however, to include under this head all the earlier portions of physics, as far as the special branches of Heat, Light, Sound, etc. Machines. — Any apparatus or instrument designed to transform or transmit energy for the purpose of doing desired work is called a Machine. Suppose, for example, that we have a supply of coal, and wish to move a train of cars from Boston to New York. The coal represents a certain amount of heat-energy, which can be obtained by burning it. In order to move the train the required distance, it is necessary that a certain amount of work shall be done. The mere production of the heat-energy by burning the coal will not move the train. How, then, can the object in view be accomplished I One method is by the use of a steam locomotive. This takes up the heat-energy of the coal, and, by various processes and contrivances, transforms it into mechanical energy, applied to its wheels in such a way as to perform the desired work. The locomotive, then, is an example of a machine. Machines are of various degrees of complexity, from that of a simple wooden rod or knife-blade to that of the most intricate loom. In our early experiments, where one ball was made to impart energy to another by collision (page 31), there was no necessity for the intervention of a machine, because the mere collision of the elastic balls served to bring about the transference of the energy. But suppose the ball A had been moving away from B, or in EFFICIENCY OF MACHINES. some direction in which it would not strike B; then, to transfer the energy from A to B, we should have required some apparatus through which such energy could be transmitted. For example, the balls might have been connected by a rope passing over a wheel in such a way as to make B move in the desired direction. Then this rope and wheel would have constituted a very simple machine. Where the energy is to be changed in form, instead of being merely transferred, the machine becomes somewhat more complicated, as where heat-energy is to be transformed into mechanical energy in a steamengine (page 286), or mechanical into electrical energy in a dynamoelectric machine (page 522). But the complication of machines arises chiefly from the complexity of the kind of work to be done, or the perfection with which it must be done, rather than from the nature of the process of transformation. Whatever its form, and however perfect or complex it may be, a machine merely transfers and transforms, but can never generate, energy. In other words, the work done, or energy given out, can never be more than the energy taken up by the machine. Efficiency of Machines. — An ideal machine would give out as useful work all the energy applied to it. In practice, owing to friction, bending, and certain laws of the availability of energy, no machine is ideal. Actual machines, then, give out less useful work than is equivalent to the energy imparted to them. The " lost " energy is merely changed within the machine into forms which are not of service for the purpose of the machine. Thus, friction causes some energy to be transformed into useless heat, and is one of the chief sources of loss in most machines. The ratio of the amount of useful work given out by the machine to the total energy put into it is called the efficiency of the machine. For instance, if a certain machine had applied to it 10 foot-pounds of energy, and, owing to friction, converted 2 foot-pounds into heat, and wasted 1 footpound in other ways, it could give out only 7 foot-pounds. The Simple Machines. — There are a few machines so simple in form and principle that they are called the Simple Machines. The more complicated machines are composed largely of combinations and modifications of these. The simple machines are sometimes called the mechanical powers They are the Lever, Wheel and Axle, Inclined Plane, Wedge, Screw, Pulley, and Knee. In studying the principles of these machines, we shall consider them as ideal — that is, as if they were without mass and weight, and as if they worked without friction, bending, etc. In actual practice these things, of course, do exist, and must be taken into account, but they do not affect the principles of the machines. so used is one form of Lever. EXPERIMENTS WITH THE LEVER. — Obtain a strong stick five or six feet long, or a crow-bar, and try to move a heavy object as shown in Pig. 51. Put F at first half-way from A to B, and notice the pressure THE LEVER, required at P to lift D or to tip it up. Place F nearer and nearer to B, and observe how the force required at P is less and less as A F becomes greater in proportion to B F. You will be surprised at the amount you can lift by making B F very short in proportion to A F. Your bar is a true lever. The force P at A will be called the working force or the power, The force L at B will be called the load. The point F of support, in other words the pivot, will be called the fulcrum. In principle, a Lever is any solid pivoted rod by means of which a force at one point is made to balance a load at another point. Kinds of Levers. — Levers are generally classed as of three " orders " ; but this classification is of no special importance, since the law is the same for all. The first order (Fig. 52) is where the fulcrum is be- F tween the two forces (power P and load L) ; the second, where the load is between the power and the fulcrum ; the third, where the power is between the load and the fulcrum. As an aid to the memory, observe that in the three orders the initial letters F L P of the middle points — fulcrum (1), load (2), power (3)— stand in alphabetical order. In Fig. 52, for each order, we have the power P working at A, the load L at B, and the fulcrum at F. The arrows represent the amount and directions of the forces L and P, and the pressure on the fulcrum F, starting with the same load L in all cases, and with P and L at right angles to the lever, which is represented as straight and horizontal for simplicity. 146 MACHINES. to turn the lever about the fulcrum F. The moment of the power is Px A F, that of the load is LxB F. For equilibrium, these two moments must be equal and must be in opposite directions (page 112). Hence, to balance a given load L may be stated thus : For equilibrium on a lever, the moment of the power must be equal and opposite to the moment of the load. Or the poiver into the leverage must equal the load, and the direction of the moments must be opposite. ILLUSTRATIVE EXAMPLES. — A man wishes to raise a stone Weighing a ton. He uses a horizontal lever of the first order, and is able to make the distance from power to fulcrum 4 feet, and that of load to fulcrum 6 inches. How much force must he exert at P ? PxAF = LxBF Suppose he weighs 150 pounds, could he lift the rock by his weight with this leverage ? No ; because he requires 250 pounds, and can obtain only 150 pounds. Of course, he might add to this weight by using other rocks. Pressure on the Fulcrum. — In the lever there must always be a pressure on the fulcrum. If the power and load are parallel, as in Fig. 52, the pressure on F will be found by the laws for the resultant of parallel forces. If P and L are in its principle. The truck (Fig. 54) is a form of lever ; the fulcrum is the axle of the wheels, and the moments are P x F C and L x F D, which must be equal and opposite. A form of bent lever which has many important applications is called the " bell-crank lever " because of its familiar use to turn corners in bell-wires in houses. Find one, make a drawing of it, and explain its principle. Among the common forms of the lever may be mentioned the pump-handle, well-sweep, shears and scissors, claw-hammer when used to draw nails, walking-beam of steamboat, oar, forceps, tongs, the steelyard, and all movable bones of the bodies of men and ani- will at the same time pass through a distance B D along another arc whose center is also at F. By geometry, AC:BD = AF:BF. But, by the law of the lever, A F : B F = L : P .-. A C : B D = L : P .-. Fx A C = LxB D. But, as shown on page 97, work is the product of the force into the distance through which the body moves ; therefore P X A C = work done by P, and L X A F = work done against L. Hence, the work done upon the lever by the working energy is equal to the work done by the lever against the load. This fact is also a necessary and direct consequence of the principle of the conservation of energy. The law of the lever might equally well be deduced by assuming that principle and working backward from it, as will be done in the case of some other machines. Actual Lever. — The demonstrations have shown the principle of the ideal lever. In the actual lever we must allow for the mass and weight of the lever, for friction, for the fact that in most cases the forces change direction and therefore leverage as the lever moves, and, finally, for the energy required to set in motion the object moved. Perpetual Motion. — It has been stated that no machine can give out more energy than is put into it ; or, in other words, can do more work than is done upon it — this being a necessary consequence of the principle of conservation of energy. If any machine could give out more energy than it received, then of that energy a part might be utilized to run the machine itself, and the rest stored up for future use. Thus the machine could keep itself going, and at the MECHANICAL ADVANTAGE. 149 same time supply energy. This would manifestly imply a generation of energy ; but we have proof on every hand that energy can not be generated, and the supposed case must, therefore, be an impossibility. Even a machine which will keep itself running without any outside supply of energy is also an impossibility, because it is physically impossible that there should not be some energy wasted — i. e., turned into unavailable forms — in every machine. Hence a machine with an efficiency of unity, or one hundred per cent, is impossible. Such machines are commonly spoken of as perpetualmotion machines, obviously because they could keep themselves going perpetually. Schemes for perpetual-motion machines, and for machines that would produce more energy than was required to run them, were much more common before the doctrine of energy was well understood than at present. That " you can not make something out of nothing," is as true of energy as of matter. Mechanical Advantage. — Although there can be no gain of energy by any machine, but must always be more or less actual loss, yet there may be a great advantage derived from its use. We are able to accomplish things with the aid of machines which we could not do without them, because the machines enable the energy at our command to do work for which it would not be available if directly applied. Take, for example, the lever. Suppose that a man who can lift only 100 pounds wishes to raise a rock weighing 1,000 pounds. It is ten times as much as he can possibly lift. He has energy enough to lift the rock to any desired height, for if the rock were in ten equal parts he could lift each separately to that height, thus doing the work, and the mere separation of the rock into parts has not increased his energy. But he can not exert force enough to lift the rock as a whole against gravity — that is, he can not exert force enough to balance the weight of the rock. Give him a lever, however, with a leverage of 10 to 1, and he can, by exerting 100 pounds on the long end, produce 1,000 pounds at the short end. and thus balance the weight of the rock. Then, by keeping up the pushing (ten times as far as the load moves) }ie can perform the work necessary to lift the rock to the desired height, doing no more work than that required to lift the ten separate parts. It is thus apparent that, although he has gained no energy, the lever has made his energy available for the purpose at hand, and therein is the " advantage." An advantage thus gained by means of a machine is called a Mechanical Advantage. Think over the various forms of lever and of other machines as you come to them, and see wherein the mechanical advantage consists, and how there is no gain, but rather some loss of energy. This is the key to the intelligent understanding of all machines. QUESTIONS.— What is meant by the term Mechanics in its strict sense ? How is it quite commonly employed ? What is a Machine ? Give examples. Why do we have to use machines ? Can machines generate energy ? If not, of what use are they ? How can we generate energy ? What is meant by an ideal machine I Why must any actual machine be inferior to an ideal machine ? What becomes of energy wasted by a machine ? In what way is much of the wasted energy used up ? What is meant by the efficiency of a machine ? A certain machine gives out as useful work two thirds of the energy applied to it ; what is its efficiency ? A certain machine wastes one quarter of the energy applied to it ; what is its efficiency ? this law. Define leverage. A man wishes to pull upward on a chain with a force of 500 pounds, and has a horizontal lever of the first order 11 feet long ; what pressure must he use if he places the fulcrum one foot from the load ? What would then be his leverage ? If he can use but 25 pounds pressure, what leverage must he have ? Where must the fulcrum be placed ? Solve the same problems with the lever of the second order. In the first problem, how much would be the pressure on the fulcrum ? Suppose that the man pressed at an angle of 45° to the lever instead of at right angles to it, how much pressure must he exert ? Suppose that both power and weight were vertical, but that the lever was inclined at 45° to the horizontal, how much pressure would be required ? Why is it usually best to push as nearly at right angles to the lever as possible ? What is the relation between the work done upon and by an ideal lever ? Between the energy put into it and that given out ? Deduce the law of the lever, starting with the principle of the conservation of energy. If, in the first problem with the lever, the man was obliged to put in one half as much more work on account of friction as was necessary to balance the load, how much must he increase the moment of the power ? If the leverage is kept tne same, what pressure must he exert ? If the pressure is kept the same, how much must he increase the leverage ? What would be the efficiency of this lever ? Show how each of the examples mentioned on page 147 is a lever, and of what order. THE WHEEL AND AXLE. it be called ? Why ? If possible, would such a machine be valuable ? Why ? How do we know that such a thing is impossible ? What is meant by mechanical advantage ? Give an example. Wheel and Axle. — Let C represent a wheel around which is wound a cord carrying a weight P. Let E D represent the axle to which C is fastened, turning in the supports. A side view is shown at A B F, on the right. Around the axle is wound a rope at G, carrying a larger weight L. In this machine, P is the power and L the load, just as in the lever ; by examining closely you will see that the wheel and axle is merely a modification of the lever. The fulcrum is at F, the axis of rotation ; the power is applied at A, at the end of a lever-arm A F; the load at B, at the end of a lever-arm B F. The moment of the power is PxA F; of the load, LxB F. As the power descends the cord unwinds, and P thus acts always with a constant arm. Similarly, as P descends L ascends, the rope winds up, and L acts always with a constant lever-arm B F. The wheel and axle is merely a device for making the lever continuous in its operation. The laws in the case of this machine are the same as those of the lever. handle of the crank, either by hand or by machinery. Such a device is often used for raising a bucket of water from a well ; and most hoisting apparatus, as cranes, derricks, etc., carries a small one engaging with a larger wheel, and so on. The second large wheel turns more slowly than the first ; the third, more slowly than the second. Thus the load winds up on the axle of the third wheel much more slowly than the power descends. Such an arrangement is called a train of wheels. Suppose that the power descends 10 inches while the load rises 1 inch ; then P x 10 = L x 1, and L = 10 P — that is, the power can balance ten times itself. In general, let a denote the distance through which the power moves, and b ing. The belt is continuous, and, starting from A, passes around B C D E F back to A. If the circumference of A C is twice that of D F, and the former drives the latter, then D F must turn twice as many times a minute as A C. Any other pulley attached to the shaft H would also turn twice as fast as A C. A large pulley on this shaft might be belted to a small one on ment may be used in reverse order to reduce speed. Inclined Plane. — Any flat surface which is not horizontal forms an Inclined Plane. A flat board more or less tipped, a " pitched " roof, a smooth hill-side, a grade on a road or railway, the sloping surface of a sand-bank, are examples of inclined surfaces more or less approaching to perfect inclined planes. In machinery, we find inclined planes in modified forms in the eccentric, cam, wedge, screw, propeller-blade, windmill fan, etc. The amount of inclination of the plane is called its grade or slope, and is measured by the amount that the plane rises from a level in a given horizontal distance, or by the ratio of the rise to the horizontal distance. For instance, if a road has such a steepness that it rises 5 feet vertically in a distance of 100 feet horizontally, then its grade or slope is said to be 5 feet in 100 feet, or simply 5 in 100, or 5 per cent. The grade may also be expressed by the angle (measured in degrees) between the surface and the horizontal. considered as acting vertically downward through the center of mass, g, of cart and load. Let g h represent this weight. Draw through g the lines g i parallel to the plane and g j perpendicular to it. Resolve the force W into components in these two directions, by completing through h the parallelogram. Then the two forces, g i and gj, will be equivalent in effect to W. Thus, owing to the weight, there is a force represented in amount and direction by g i pulling the cart downward along the plane, and another simultaneous force, gj, perpendicular to the plane. The force gj can not result in motion, since it is wholly counterbalanced by the resisting pressure of the plane. The force g i will produce motion down the plane, unless counterbalanced. The cart will, therefore, run down the plane. But notice that the force g i is less than W ; hence the acceleration down the plane will be much less than if the cart were allowed to fall freely in a vertical direction. To hold the cart in equilibrium we must, then, apply a pull along the cord in amount equal to g i. Observe that, if the grade is made greater, the amount of g i will be greater for the same load W ; hence g i increases as the grade increases. A horse pulling a wagon up a hill has to pull with more force as the slope grows steeper. The Friction of any Body moving over a Surface is proportional to the pressure against the surface. Notice that gj diminishes as the pitch increases, and is always less than W. Hence, the steeper the pitch, the less the work against friction. To pull the Cart up the Plane, then, by a force parallel to the plane, we must apply energy at a sufficient rate to produce, first, force enough to balance the backward pull g..i, and, in addition, enough more force to do the work of friction necessary to move the cart at the desired speed, and also to accelerate the cart if it is to be started from rest or is to be moved with accelerated motion. This is the energy supplied by an engine drawing a train up a grade, or by a person in walking up-hill. Work on Inclined Plane. — Force parallel to Length. — Suppose the cart to be pulled up the length ad of the plane by a force P parallel to ad. The work performed by the energy which produces the force P will be ANGLE OF REPOSE. 155 measured by P X ad. The work done upon the cart, if friction be neglected, consists in raising it through a distance equal to e d against the resistance W of its weight, and is therefore Wxed. These two quantities must be equal to each other by the principle of the conservation of energy. Therefore Pxad = Wxed, or P : W = ed : ad = height : length. This would be the least value of P for a given weight W. In any actual case, the work done must be greater than P x ad, and therefore the actual working force must be greater than P by an amount necessary to do the work of friction, of acceleration, etc. Force parallel to Base. — In its application to machinery, the inclined plane is used to raise or force apart bodies or portions of machines. For instance, the rod A B, running in the guide C D and pressing downward with a force F, may require to be lifted. This may be done by forcing under it the inclined plane a d e sliding on the surface G H. Let the pressure be exerted by a force P parallel to the surface G H. How great must this force be in order to push A B backward against F ? Suppose the plane moved along so that the whole length a d is gradually pushed under A B, which will thus be lifted against F through a distance equal to e d. The work done upon it will then be F x ed. The work done by P will be P x ea, and this, friction being neglected, must be just equal to F x ed. Therefore, P x ea = F x ed .'. P : F = ed : ea = height : base. This would give the minimum value of P. In an actual machine, P would be enough greater to do the work of friction, acceleration, etc. FIG" 61' . Angle of Repose. — If any body is allowed to roll or slide down a grade, then gravity furnishes the energy to do the work of friction and acceleration. In this case it will be seen that, since friction is a retarding force, and g i diminishes toward zero as the pitch of the plane is made smaller, there will be a certain pitch at which the force g i will be just equal to the friction. At this pitch the body will continue to roll or slide at a uniform velocity when started, because under balanced forces and therefore following the first law of motion. If the angle is further diminished, the force g i will become less than the friction, and the body if started will soon stop. The angle at which this result is just reached is called the Angle of Kepose. Pour sand slowly out of a pail or beaker upon the table. It will pile up steadily at first ; but soon the slope of the sides of the pile will be equal to the angle of repose for sand, and any more sand poured upon the top will slip down over the sides to the foot of the pile, and the angle of the sides will be maintained nearly constant. Or build up a high pile of moist sand, and let it dry. Jar it a little and it will begin to fall and continue falling until the slope of the sides is the angle of repose of the dry sand. For this reason, at the foot of sand or gravel banks and rocky cliffs, the natural piles of fallen material will be seen to have quite a uniform incline. The slopes where a railroad-bed has been constructed by filling in, or by cutting through gravel or sand, illustrate the angle of repose. Experiments should be tried by the pupil in measuring the angle of repose for various substances, as for blocks of different material on a board arranged to tip at various angles ; for gravel, shot, etc. The angle of repose of water is zero — that is, the surface of a mass of water is perpendicular to the line of action of its weight, and is therefore what we call level ; yet the surface of water is not a plane, but a part of a sphere with its center at the earth's center. The Wedge. — Fig. 62 shows the Wedge in its simplest form. The action here is merely that of the inclined plane. The solid ade in Fig. 61 is really a wedge, and its upper and under THE SCREW. 157 the principle of the wedge. The surfaces of the wedge may be curved instead of plane, as in the case of the points of pins and needles, awls, etc., and the sharp edges of all cutting tools as seen through a magnifier. The mechanical advantage gained by the wedge is greater as its slope is less ; but for cutting tools the slope has to be adapted to the materials to be cut, being less for wood and soft substances than for iron and other metals. QUESTIONS. — Describe the Wheel and Axle. Deduce its law. How is it related to the lever ? Give examples. If the length of lever used in a capstan is 4 feet and the drum is of 6 inches radius, how much pull on the rope would be created by a force of 50 pounds on the end of the bar ? Describe the Inclined Plane. Give examples. What is meant by the grade or slope of an inclined plane ? A plane rises 4 feet in 200 feet. What is its grade or slope ? Measure the slope of a d (Fig. 60). If the weight W is 10 pounds, what is the pull gi ? What is the pressure gj ? How much weight would be required at P to prevent the cart from moving ? A horse is going up a hill with a grade of 5 feet in 100, and is drawing a load of a ton. How much force must he pull with ? If he has to do 10 per cent additional work for friction, how much must he pull ? If he ascends 150 feet vertically, how much work must he do, B. E. U. ? If the grade is twice as great, how much must he pull ? The Screw is one of the most important modifications of the inclined plane. Let A B (Fig. 63) represent a solid, circular cylinder of metal or wood. Let 0 D E F be a sheet of paper cut so that C D is perpendicular to D E, and 0 F slopes by any suitable amount. The paper will then illustrate the side view of an inclined plane as in Figs. 60 and 61. Fasten this on the cylinder with C D parallel to its axis, and then wrap the paper around the cylinder. The edge C Gr F will wind itself up as a spiral line around the cylinder, as shown in the dotted lines Gr, H, I, etc. plane, but wrapped around a cylinder instead of being flat. If you turn such a screw with your pencil-point in the channel between the threads, the point will rise gradually, just as it would rise along an inclined plane. Most screws are made with a V-thread, as at P (Fig. 64), instead of the square one ; but you will easily see that this in no way changes the principle of their action. pressures. Suppose the nut N (Fig. 64) to be held firmly in place and the handle A of a lever in the head of the screw to be turned in such away as to advance the screw. Any object at C would be pushed upon with a great pressure, Or the screw may be held from advancing, and the nut will then be pressed forward or backward. stance, if this distance were -fa inch, the screw would be said to have a " pitch " of -fa of an inch ; or it would be said that the screw had 20 threads to the inch. From the law of the inclined plane, it will be seen that the pitch of the screw corresponds to the height of the plane and the circumference to the base. The law of the screw could then be deduced from that of the inclined plane, but it is better to deduce it directly. Suppose the screw turned by energy causing a force P at A always at right angles to the lever A D. Let A B be the arm of this force ; then the distance S passed over by A in one turn of the screw will be the circumference of a circle with A B as a radius (viz., S = 2 x 3-141 X A B). The work done upon the machine will be P x S. In one turn the screw will be advanced at C by a distance equal to its pitch, which we will call s. Let F represent the force exerted by C. The work done at C will then be F x s. Neglecting friction, then, we must By way of example, if we had a screw of a pitch of £ inch turned by a force of 50 pounds at the end of a lever of length A B = 2 feet, how much work could that screw perform per rotation and how much force or pressure could it produce at C ? The work it could A screw of about these dimensions, called a Jack-Screw (Fig. 65), is used in raising buildings temporarily from their foundations, as well as for other purposes where great force is necessary. The common letter-copying press (Fig. 66) is another example of the application of the screw. motion of the wheel. The Pulley is merely a wheel, usually grooved on its face to hold a cord or rope, and suitably mounted on an axle. It serves merely to change the direction of the pull of the rope passing over it. For instance, the pulley P (Fig. 68) changes the direction of the pull A exerted by the hand to the desired direction, B. If friction be neglected, the force B equals the force A. The relative and absolute directions of the parts A and B of the rope make no difference whatever. Take the familiar case of two bodies of weights W, and Wa hanging on a cord laid over a pulley (P, Fig. 12) : you know that, except for friction and weight of cord, W, must of the pulley where the forces happen to be vertical. If you pull steadily upon the end of any rope or cord in any position, there must be at every point throughout the cord a pull of the same amount, except for slight differences due to the weight of the cord itself or to friction. upon B. Note that there are two lines of rope connecting A and B. If, now, P is pulled sufficiently to lift L, you will see that for every foot that B (and therefore L) is raised, each line of rope between A and B must be shortened one foot, and therefore two feet of rope must be taken over A toward P. That is, for each foot that L is lifted, P must move back through two feet. In the second set of pulleys, the pulleys C and D are fixed and E is free. There are three lines of rope connecting the fixed and free pulleys. Then for each foot that L rises, three feet of rope must be pulled back toward P. In the third set, there are four lines of rope between the fixed and free pulleys. Hence P moves back four feet for each foot of rise of L. Law of the Pulley. — In every case, then, the law of the pulley is as follows : Let S represent the distance through which the moving force P is exerted, and s that through which the load L is raised. The work done by P will, be P S, and this must be equal, neglecting friction, to the work L s done upon the load. Then P S = L s, or P : L = s : S, connecting the fixed and movable pulleys. EXAMPLE. — If we wish to raise a load L of 1,000 pounds by the third set of pulleys, how much would be the least pull required at P I In this set n = 4 .-. P : 1,000 = 1:4, therefore P = J-«p = 250 pounds. Note that in this as in other machines the working force must be greater by an amount necessary to do the work of friction and of acceleration. The amount of friction in the pulleys is so great that a very large part of the work is wasted, and there is no practical gain in using a pulley of more than two or three sheaves. The mechanical advantage gained ds an increase of force. For the sake of compactness, where there are several pulleys at each end they are put side by side in a " block," as shown in the fourth set in Fig. 69. The single wheels in such a block are called the " sheaves." The whole system is sometimes called a " tackle." form this machine. The bars A C and A B are almost in line, so that the angle B A 0 is nearly 180 degrees. If a force is applied at the joint, as shown in amount and direction by P, it will produce large forces Fj and F2 tending to push the surfaces at B and C apart. It will be seen that the and Fo produced by a given working force P. The Equal- Arm Balance is an adaptation of the lever for the purpose of weighing. It consists of the " beam " A B (Fig. 71), supported on the knife-edge C, usually a three-cornered steel bar passing horizontally through the beam at right angles to it. The sharp lower edge of C rests on steel or agate supporting plates, D. At the ends F and G of the beam are two smaller knife-edges parallel to the other, but edge upward. These edges are at equal distances from the central knife-edge, and on this the accuracy of the balance depends. Hung upon these end knife-edges by means of steel or agate plates are the scale-pans H and I. In one pan is placed the object to be " weighed," and in the other are placed the standard masses. A pointer P is attached to the beam at 0, and as the beam tips, this moves 'over a graduated scale. The equal-arm balance has been carried to a very high grade of accuracy. It has been made so sensitive as to detect a difference of much less than one millionth part of the whole mass upon it, and to show the weight of less than y^ milligramme. The balance used in Weighing. — The use of the balance is called Weighing. It is a process for ascertaining the mass of any body, and depends on the principle of the equilibrium of moments. The arm of one force is 0 F, that of the other C G, and these are made exactly equal, as are also the weights of the pans. The balance can swing evenly only when equal forces are applied at F and G — that is, when the weights of the substances in the pans are equal. The process is as follows : The balance is set swinging without a load, to see if it is in " adjustment " — i. e., if it swings equally on each side of the middle point ; if not, it is adjusted until it does so. The body whose mass is to be determined is then put into one pan, usually the left-hand one for convenience. Masses from the graded set of masses (pages 81 and 89) are put into the other pan until the pointer again swings equally. The weight of the unknown body and of the known masses in the pan are thus shown to be equal ; therefore, the masses are also equal. The mass of the unknown body is found by adding the known masses used. If the balance arms C F and C Gr are not exactly equal, then there will be an error in the result. This may be avoided by putting the object in the right-hand pan, and filling shot or sand into the left until equilibrium is obtained ; then removing the object and putting in standard masses until equilibrium is again obtained. A rough balance may thus be made to give much better results. QUESTIONS. — Show how the Screw is a modification of the inclined plane. Describe the Nut. Define the pitch of a screw. How may the screw be used to obtain great pressure ? State the law of the screw as thus used. A jack-screw, with a pitch of one quarter of an inch, is turned with a force of 75 pounds at the end of a lever of 2 feet ; how much pressure could the screw produce, neglecting friction ? How much work can it do per turn ? Describe the Endless Screw. "What is a Pulley ? What is its use ? How can a mechanical advantage be gained by the use of a combination of pulleys ? State the law of the pulley. Show how this is true from the amount of rope drawn through each of the pulleys. State the rule for finding the ratio of motion of power to load. In each of the four sets of pulleys of Fig. 69, what load would a power of 100 pounds just balance ? Describe the Knee or Toggle Joint. In Fig. 70, suppose that P = 100 pounds, what would be the amount of F, ? What would be the force with which D and E would be pressed upon ? Describe the balance ; the process of weighing. Think of a reason. Could a carriage progress without friction ? Can a train be moved if the rails are thoroughly lubricated ? Grasshoppers crushed by the wheels of the cars have been the means of stopping trains in the West. Did you ever attempt to lift a ladder from the ground by walking under it and grasping round after round in succession ? Why did you experience difficulty, or were perhaps forced to give up the feat, as you approached the bottom ? A. dynamo-electric machine, having an efficiency of 93 per cent, receives 2,000 foot-pounds of energy ; how much electrical energy does it give out ? It receives energy at the rate of 40 horse-power ; at what rate does it give out electrical energy ? A farmer, in forcing a stump from the ground, uses a crow-bar 6 feet long, which he rests on a stone 5 feet from the end where his hand is applied. The resistance of the stump is equal to a weight of 500 pounds ; how great a pressure must he exert to move it ? A man weighing 180 pounds and a boy of 60 pounds are teetering on i. .board 12 feet long. That they may balance each other, how near must the man t^t to the horse on which the board rests ? Four men are drawing in, with a capstan, an anchor that weighs 1,000 pounds. The barrel of the capstan has a radius of 6 inches. The circle described by the handspikes has a radius of 5 feet. How great a pressure must each of the four men exert to move the anchor ? 1QQ THE THREE STATES OF MATTER. A book-binder has a press, with a screw whose threads are one third of an inch apart, and a nut worked by a lever which describes a circle of 8 feet ; how great a pressure will a power of 5 pounds applied at the end of the lever produce, the loss by friction being equivalent to 240 pounds ? Matter exists in Three Conditions or states, which are called respectively the Solid, the Liquid, and the Gaseous State. Liquids and gases are also called Fluids. Solids. — You are familiar with matter in what is called the solid state. A stone, a piece of wood, metal, or ice, are every-day examples of solids. If you think about all the solid substances which you can call to mind, you will see that they have this property in common, viz. : They retain their shape when left to themselves, and can only be made to change shape by the application of energy. Liquids, on the other hand (water and mercury are everyday types), must be held in a vessel of some kind. If left to themselves they do not retain their form, but spread out over the surface on which they are placed. Owing to the action of their weight, liquids do not require to be held down at their upper surface, but can be kept (except for evaporation) in a vessel open at the top. All liquids may probably be red Toed to solids by sufficiently great cooling. Nearly all have been thus solidified. Gases, like liquids, require to be held in a retaining vessel ; but, unlike liquids, if left to themselves, gases will spread or expand in all directions. Hence the vessel containing them must be closed on all sides. Air is a common SOLIDS. 167 example of a gas, or rather of a mixture of gases. All gases may be reduced to liquids : some by great compression alone; others by great cooling alone; others require both cooling and compression combined. The Molecular Differences in the Three States are as follows : In all three states the molecules are in the continual to-and-fro motion of heat-energy, but with this difference — in the solid state, the molecule does not wander about through the body, but remains always at or very near the same point, simply moving to and fro, somewhat as a pendulum-bob vibrates about its point of rest, but more irregularly. In the liquid state, every molecule does wander in a very irregular path, and somewhat slowly, through the body of the liquid, being now at one point and presently at another, jostling violently around among its neighbors. In gases, each molecule moves around as in liquids, but much faster and with a freer motion. The spaces between the molecules are much greater, so that they can move farther without jostling against one another. PROPERTIES OF SOLIDS. Cohesion. — Adhesion. — Take hold of the ends of your pencil with your fingers, and pull lengthwise (not crosswise), as if trying to pull it apart. It resists so strongly that you can not do so. Try to break any object in any way ; the breaking is more or less resisted. Break a small stick of wood by pulling or bending. It breaks by the pulling apart of its molecules. Put the broken surfaces again together, and they do not hold. Yet the only difference in conditions is that you are unable to get them back to the same closeness of contact that they had before. kind, this force being very great at extremely short distances, but being so slight as to be imperceptible at distances of a few thousandths of an inch. The property of possessing this force is called Cohesion, and the force is called the Force of Cohesion, or often merely Cohesion. A similar force exists between surfaces of matter of different kinds. It is shown when you try to pull apart pieces of wood glued together, or cemented bricks. The force which holds the glue to the wood or the cement to the brick is an attraction between materials of different kinds, and is called Adhesion. The distinction between cohesion and adhesion is of little consequence ; they are probably both due to the same form of energy. gases to a very limited extent. It is to cohesion that the strength or tenacity of materials is due, and the limit of strength is reached when the force applied to the body is equal to the cohesive force exerted by the body in opposition to that force. That surfaces may be brought so closely into contact as to cohere or adhere, is shown by the fact that gluing, cementing, soldering, welding, varnishing, etc., are possible. EXPERIMENT. — Cut a lead bullet in two, and make the fresh surfaces exceedingly smooth and flat. Press them firmly together. They will cohere perceptibly. Lay a very smooth piece of plate-glass on the table. Place upon it another (of a little larger size, for convenience of lifting by the edges), and put a weight upon them. After a while carefully remove the weight, and pick up the top plate. The lower plate will be found to cohere more or less strongly. Two such plates left lying together for months or years may cohere so strongly as to be more easily broken than pulled apart. Machinists and others who have occasion to make very truly plane surfaces have what they call "surface plates," by which to test the surfaces which they are making. These consist usually of three steel plates which have been alternately ground together in pairs until each fits both the others, and all are therefore plane. If these be cleaned and put together, they adhere quite firmly, even in vacuo. suitable shape. They are then heated, and while hot are cleaned again by means of a material called a flux (rosin, borax, etc.), and brought into contact. They are then hammered or pressed together to bring them into closer contact, and allowed to cool. When cold, they cohere or adhere nearly or quite as strongly as the other parts of the material. The blacksmith can thus weld wrought-iron easily and a few other metals with difficulty ; but the process of welding by electricity has rendered this property available in the case of almost all metals. Hardness. — A body is said to be harder than another when it is capable of scratching the former but not of being scratched by it. The diamond is the hardest of all solids. Hardness is made use of in mineralogy as a means of identifying minerals. By sudden cooling from a high temperature, steel and some other bodies acquire great hardness, usually accompanied with increased brittleness. Bodies thus treated are said to be tempered. Ductility is that property which renders some materials capable of being drawn out into wires or threads. Glass when hot can be spun into threads. Warm wax can also be thus treated. Many metals when cold possess the same property. Thus, gold, silver, platinum, iron, copper, palladium, aluminum, zinc, tin, lead, can all be drawn into wires when cold by pulling them through hard metal plates bored with holes of suitable sizes. Gold is the most ductile metal, and the others stand in the list above in the order of their ductility. Malleability is that property which renders a body capable of being hammered or rolled into sheets. Gold, copper, and other metals are quite malleable. This property and ductility are closely related ; but the metals do not stand in precisely the same relative order for the two. Consult pages 62 and 67. 170 SOLIDS. Elasticity. — From the experiments described on pages 49 to 52, you have learned that when a force is applied to a body which is prevented from being accelerated, the body is changed in size or form ; also, that when the applied force is removed, the body will more or less completely regain its original form. The force acting in such a case is called the Stress ; the change in form produced during its action is the Strain. Elasticity is that property by virtue of which a body (whether solid, liquid, or gaseous) requires force to change its bulk or shape, and resumes its form when the force is removed. Suppose you were to take a round rod of rubber a foot long and an inch in diameter and a piece of steel of the same size, and were by any means to hold each stretched by the one-thousandth part of its length. To do so would obviously require a much greater force with the steel than with the rubber. Which is the more elastic ? You would perhaps naturally say the rubber ; but this is not the case. The rubber is the more extensible, but the steel is the more highly elastic. The elasticity of a body is measured by the amount of force required to produce a specified change of size or form ; hence the greater the force required, the greater the elasticity. When we are dealing with the reduction of the volume or length of a body by pressure, we speak of compression ; when with the increase of length, of extension ; when with its bending, of flexibility. The latter is, as stated on page 51, a combination of compression and extension. If we say that one body is twice as compressible or extensible or flexible as another, we mean that equal forces will produce twice the amount of compression or extension or bending on pieces of the same size. In such a case, the first body would be only half as elastic as the second. Some substances can be stretched, compressed, or bent but a little before breaking, and are said to be brittle. Substances the reverse of these are called tough. fectly elastic, while those which do recover completely are called perfectly elastic. Many substances appear to be perfectly elastic if not strained beyond a certain amount. Hold in the hand or under a clamp one end of a bit of iron or copper wire. Pull the other end aside a very little so as to produce slight bending, and let it go. After vibrating for a while it will settle down in its original position of rest. So far as you can see, it is perfectly elastic. Repeat the experiment, bending the wire a little more each time. You will soon find that the recovery is not perfect, but that the wire has been " bent," or has taken what is called a " permanent set." Its elasticity is perfect only below a certain amount of strain. This amount or limit below which the substance is perfectly elastic, or sensibly so, is called the limit of elasticity. Some solids (steel, glass, etc.) can be strained nearly to the breaking point without passing this limit ; others (wax, rubber, copper, gold, and ductile materials generally) reach the limit at much less strain than is required to break them. If a substance is kept in a strained condition for a long time, it will generally show a permanent set on being released, even when it has been strained much less than up to what appears to be its limit of elasticity for strains of short duration. Structure. — Examine and compare a lump of blue vitriol (copper sulphate), a piece of mica, a bit of pine wood, a piece of sandstone, a fragment of glass. You will find the lump of vitriol made up of a number of more or less regularly shaped masses of the salt. It is composed of imperfect crystals, and is said to have a crystalline structure. All crystals split or " cleave " more readily in some directions than in others. Thus mica splits into thin plates or layers (lam'-ince), and is therefore said to have a laminated structure. Wood splits easily along the grain or fiber, and is said to have a fibrous structure. Sandstone is made up of a multitude of grains, and is therefore described as having a granular structure. Glass splits equally well in all directions, and appears to be without structure, which is expressed by saying that it has an amorphous (without form) structure. liquid and stand it aside in a quiet place free from dust. In a few hours or days there will be found on the thread crystals of alum more or less perfect. Similar experiments may be made with copper sulphate, common salt, and other substances. If in the winter you catch snow-flakes on a dark cloth, you will see, especially well with a magnifier, that they are usually composed of regular and beautiful crystals of ice (see page 277). The frost which forms on the window-pane is also generally crystalline. Viscosity. — Certain substances which we commonly regard as solids do not strictly fulfill the definition of a solid as a substance which holds its form when left to itself. EXPERIMENT. — Fasten one end of a stick of sealing-wax so that it projects horizontally, as the stick in Fig. 14. Leave it for a day or two. The projecting end will have become permanently bent downward. A piece of pitch left lying upon a table will after several days be found to have flowed out into a flat mass, as thick molasses would have done much more quickly. This slow change of form is due to a sort of flowing of the parts of the substance. Solids acting in this way under ordinary conditions may properly be considered as imperfectly solid. They are said to be viscous. QUESTIONS.— What are the three states of matter ? What is the characteristic by which we recognize Solids ? Give examples of solids. Is putty a solid ? Is ice a solid ? What is the main distinction between solids and liquids ? Give examples of liquids. Are sealing-wax and pitch liquids ? How may liquids be rendered solid ? What is the chief distinction between gases and liquids ? Give examples of gases. How may gases be reduced to the liquid condition ? Give an example of some substance which you know of as capable of existing in all three states. State the molecular differences between the three states. Show that Cohesion and Adhesion exist in solids. What is the distinction between the two terms ? Do these properties exist in liquids and gases ? To what extent ? Is cohesion or adhesion perceptible at long distances ? Give examples to show what the distance is at which they are perceptible. To what is the strength or tenacity of materials due ? To what form of energy is cohesion due ? On what does the possibility of welding, soldering, gluing, etc., depend ? Describe these processes. Describe an experiment showing the adhesion of liquids to solids. One showing the cohesion of liquids. What is meant by Hardness ? By Temper ? By Ductility ? Give examples. Define Malleability, Elasticity, Stress, Strain. Which is the more elastic, iron or wood ? Brass or rubber ? WThich is more easily extensible ? What is meant by Brittleness ? By Toughness ? Illustrate. Give examples of permanent set. What is meant by limit of elasticity ? Describe crystalline, laminated, fibrous, granular, and amorphous structure. Define Viscosity ; give an example. Cohesion. — Adhesion. — If you dip a pencil or your finger into water, you will find, on drawing it out, that some water clings to it. This is because the water adheres to the pencil or finger, and also coheres — that is, holds together. Most other liquids act similarly ; but mercury and certain molten materials do not, although they possess the properties of cohesion and adhesion. NOTE.— The properties of liquids and gases discussed in the following sections may be illustrated measurably with the apparatus shown above. Methods of constructing simply and cheaply various essential pieces are suggested in the text. No. 1 represents an adhesion plate ; 2, cohesion figures ; 3, equilibrium tubes ; 4, upward pressure apparatus ; 5, brass bucket with accurately fitting solid piece of brass to illustrate the principle of Archimedes ; 6, capillary tubes ; 7, tall glass jar, with tube and funnel ; 8, stoppered glass bottle ; 9, barometer tube : 10, hollow copper globe for weighing air, with stop-cock and scale-beam for suspension ; 11, automatic table air-pump ; 12, lifting and force pump ; 13, Boyle's law apparatus; 14, siphon; 15. large-mouth glass bottle, inverted over porous cup, from which a glass tube dips into a tumbler of water. The iron stand is similar to that described on page 230. Teachers and pupils are referred, for such of this outfit as they can not readily construct for themselves, to any instrument-maker. LIQUIDS AND GASES. EXPERIMENTS. — At the middle of a thin disk of metal or glass, fasten a hook with solder or wax, as shown in Fig. 73, or drive a screweye into a flat piece of wood. Into the hook or eye, loop a rubber band. Bend the hook until the disk hangs truly horizontal. Then, holding the upper end of the rubber in the hand, lower the disk (which must not be greasy) until it touches a water surface. Pull carefully straight upward. You will find that you have to pull quite hard, as you perceive from the stretch of the band, before the disk tears away from the water. The water and disk therefore adhere. But this experiment also illustrates the cohesion of the water ; for, if the particles of water did not hold together, the disk would have to lift merely the weight of those particles which adhered to it, and would therefore be no harder to lift before it separated from the liquid than afterward. In fact, what we really do when we pull the disk away from the liquid, is to tear apart the cohering water particles, and not to pull apart the water and the disk. shown in Fig. 74. Dip the circle into the soap solution. On drawing it out, a thin film will be found filling the circle. This illustrates both adhesion and cohesion. How? Dip the other forms. They will show when taken out extremely interesting combinations of films. By breaking one or another of the several films of the cube, peculiar curved surfaces can be formed. of cohesion, color, etc. Surface Tension. — Let water drop slowly from the end of your finger. A drop as it falls through the air is spherical. Rain-drops are also spherical, as you can see by watching closely, and as is proved by the rainbow (see page 368). A drop of water on an oily or smoked surface, or a drop of mercury on the table-top, has the form of a sphere. Why is it that these small masses of liquid take this form ? Remember that the force of cohesion between the molecules is very strong when they are exceedingly close together, but ceases to be sensible at even very short distances. Let a, Fig. 75, represent a molecule inside a mass of liquid. Then a would feej the pull of all the molecules which are within a certain short distance of it, but not of those beyond that limit. Let the small dotted circle indicate a sphere described about a as a center, at such a distance that the attraction on a of all molecules inside the sphere is sensible, but that of FTG- TS.-SPHERE OF those outside is insensible — i. e., is less than some specified small amount. This sphere is called the sphere of attraction of a. For water, the radius of this sphere — i. e., the distance at which cohesion ceases to be sensible — is about two millionths of an inch. Now there would be the same number of molecules on all sides of a within its sphere of attraction; hence a would be equally pulled in all directions, and cohesion would not, therefore, tend to move it in any one direction more than another. Suppose now that we have a drop of water represented as highly magnified by the outside circle of Fig. 75. Let the large dotted circle be drawn so that its distance from the outer one is just equal to the radius of the sphere of attraction (two millionths of an inch). Any molecule lying inside this dotted circle will then be equally pulled in all directions. But for all molecules, for instance, c and d, lying between this and the surface of the drop, there will be no molecules in those parts of their spheres of attraction which are outside the drop surface. Hence all molecules near the surface will be more strongly attracted toward the interior of the drop than toward its surface, and for those molecules very close to and at the surface, the pull will be very strong. This is true of every free liquid surface (i. e., not bounded by a solid or other liquid). The surface of a liquid, therefore, acts as if it were under a continuous pull or tension ; it is therefore said to have a Surface Tension. By this surface tension the liquid is forced to take that shape which gives the least surface for the given volume of liquid, and that shape is a sphere. A perfectly spherical form is not attained by a drop lying on a solid surface, because the weight is great as compared with the cohesive force, and flattens the drop out. The rounded form of a drop of melted wax, of the softened end of a melted stick of sealing-wax or of a glass tube or rod, of a soap-bubble, etc., is due to the action of the surface tension, as are also the phenomena of capillarity about to be described. Solid surfaces also must possess a surface tension, but its effects are seldom perceptible. Annealing. — A similar condition of surface tension is exhibited by " Prince Rupert drops," which are made by allowing drops of molten glass to fall into water. The outer surface of a drop is thus suddenly hardened, while the interior remains liquid. As the interior gradually solidifies, it contracts, putting the surface layers of solidified glass under great stress. If the surface is scratched or cut, the crack thus started is violently spread by this stress in many directions, and the drop flies instantly into fragments. This strained condition, due to sudden cooling, may be reduced or avoided by the process of Annealing — i. e., by slow cooling either at the time of making or after subsequent heating. Most glassware has to be annealed. To produce homogeneous and unstrained or evenly strained glass for large telescope lenses, extraordinary pains are taken in the annealing process. GLASS PISTES. Capillarity. — If you dip a clean glass plate into a dish of water, the water will rise up at the surface of the plate in the curves C and D (Fig. 76) instead of lying flat. This is because the adhesion of the water to the glass much exceeds the cohesion of the liquid. Dip the lower edge of the combination into water, and the liquid will rise in the form of the curve shown in the figure. Obtain a clean glass tube of about a tenth of an inch in diameter. Dip it vertically into water. The water will rise in the tube. Try finer tubes. The finer the tube, the higher the water will rise. Fine tubes are called capillary tubes (from the Latin capillus, a hair), because of their hair-like bore. From the fact that the action just illustrated is easily seen in these capillary tubes, the phenomenon is called Capillarity. In a glass tube one tenth of an inch in inside diameter, water will rise to a height of a little more than one quarter of an inch. The height for the same liquid is inversely as the diameter of the tube, but varies with the liquid. Thus in a tube of O01 inch diameter, water will rise 0-1 -r- 0-01 = 10 times as high as in one Ol inch diameter, or 10 x 0-25 = 25 inches. Liquids will not overflow a tube by capillary action. If a tube O'Ol inch diameter were dipped into water until it projected only half an inch, the water would rise to the top of the tube and stop, because of the change in form of the tube at that point. CAPILLARY TUBES. Water and most liquids adhere to glass and other solids more strongly than they cohere. But this is not true of mercury, which adheres to glass less strongly than it coheres. Fig. 79 shows the action of mercury if the capillary tubes of Fig. 78 were plunged into it. The cohesion of the mercury is so much greater than the adhesion to the glass that the mercury does not wet the glass like water, but assumes a convex form, as water does upon a smoked or greasy surface. The toy called a "sucker" is a round piece of leather with a string fastened to the middle. If it be thoroughly we^ and pressed firmly down upon a flat stone, some water ceed the weight of the stone, so that it can be lifted. Porous Objects absorb Liquids by Capillary Action.— Pores form irregular spaces, into which liquids rise or flow just as water rises in capillary tubes. Blotting-paper, a lump of sugar, a lamp-wick, absorb liquids in this way. But you will remember that the cause of this action lies wholly at the surface of the liquid, and that as a rule the liquid can not be made to overflow. Therefore, a continuous flow of liquid can not be due to capillarity unless the liquid is evaporated or otherwise removed from the surface, as, for instance, in the case of a lamp-wick. Compressibility. — By very exact experiments, it has been shown that liquids are compressible — i. e., that their volumes may be reduced when under pressure. Water is only very slightly compressible, even with enormous pressure. Diffusion. — Pour into a tall glass jar or bottle enough water to fill it two thirds full. Through a funnel and long tube reaching to the bottom, introduce carefully about one third as much of a nearly saturated solution of blue vitriol. Let the glass stand without disturbance for several days. You will see that at first the surface between the blue solution and the water is sharply defined. Soon it becomes blurred, and gradually the vitriol spreads up through the liquid until the whole becomes of a uniform tint. This process is called Free Diffusion. It is due to the fact already stated (page 167) that the molecules move about from one part to another of the body of a liquid. EXPERIMENTS. — Into a similar jar put a solution of blue litmus in place of the water, and then pour in through the funnel a small amount of sulphuric acid. In Place some blue vitriol solution in a porous cup, such as is used in some electric batteries. Stand the cup in a dish of water, but with its top out. The blue vitriol will diffuse through the cup into the water. A similar experiment may be made with the acid and litmus. This diffusion through porous partitions is not different in character from the free or direct diffusion, but the principle is made practical use of in many ways. Kate of Diffusion. — Some substances diffuse rapidly, others very slowly. Most of those solids which diffuse rapidly when in solution are such as have a distinctly crystalline form, such as common salt, sulphate of magnesium, etc. This class is therefore called crystalloids. Of the substances which diffuse very slowly or hardly at all, gelatine, starch, dextrine, and gums are examples. They all form, when moist, more or less gelatinous or glue-like masses, and are therefore called colloids (from a Greek word for glue). The reason why the colloids diffuse so much more slowly, is probably because their molecules are very large as OSMOSIS. by means of a clamp. Note the height 0 at which the solution stands at the outset. After an hour or two, the liquid at C will be found higher than at the start, showing that more of the liquid has diffused from B into A than from A into B ; but the color (or taste) of the liquid in B will prove that some liquid has also diffused from AtoB. Thus liquids and solids in solution diffuse through animal membranes. But such membranes as the bladder are different in structure from the porous cup of the former experiment ; they contain no pores which can be discovered even with a powerful microscope. Hence it is not strange that the process of diffusion through such membranes, which is called Osmo'sis, follows different laws from free diffusion or diffusion through porous substances, and depends on the nature of the membranes used. Osmosis has important practical applications. It also enters largely into the operations of Nature, causing, for instance, the ascent and descent of sap in trees and vines. QUESTIONS.— Show that cohesion and adhesion exist in liquids. What is surface tension ? To what is it due ? Describe it in detail. What is meant by the sphere of attraction ? At how great a distance does the cohesion of water cease to be sensible ? Why do rain-drops assume a spherical form ? What do the Prince Rupert drops illustrate ? How are they made ? What is the process of annealing ? To what phenomena is the name Capillarity given ? Describe several experiments illustrating it. How high would water rise in a tube of 0'03 inch bore ? Will liquids overflow in capillary tubes ? Why not ? Why does oil rise in a lamp-wick ? If the end of a piece of dry wood is dipped into water, why does the water rise in the wood ? What is necessary in order that a liquid should wet a solid ? Describe the action of mercury in fine tubes. Why does it act in this way ? Describe and explain the action of the toy called the " sucker." Are liquids compressible ? Describe an experiment illustrating the free diffusion of liquids. One illustrating diffusion through porous substances. What is the molecular explanation of the process of free diffusion ? What is the difference between crystalloids and colloids ? Describe an experiment showing the phenomenon of Osmosis. Are the laws of osmosis different from those of free diffusion and of diffusion through porous partitions ? For what reason ? PRESSURE OF LIQUIDS. Hydrostatics. — Hydraulics. — Hydrostat'ics is the name given to that branch of Physics which deals with liquids at rest ; Hydraulics, to that branch which has to do with liquids in motion. out the liquid. Fig. 83 represents a vessel filled up to a b with any liquid, and a b is a piston which can be forced down by pressure. Suppose, for example, this pressure to be equivalent to 2 pounds on each square inch of the surface of the piston. Then it will be transmitted through the liquid in every direction, so that on each square inch of the walls of the vessel, e. g., at F, E, D, C, or anywhere else, there will also be a pressure of 2 pounds to the square inch, if we neglect for the present the weight of the liquid itself. Further, if we were to put into the liquid a sheet of metal or any object whatever of any size or shape, there would be a pressure of 2 pounds on each square inch of its surface. Or, if we think of any two parts of the liquid as separated by an imaginary plane moving in any direction, then upon each side of this plane there will be a pressure of 2 pounds to the square inch. The pressure is thus the same through all parts of the liquid, and at every point it is equal in every direction. Of course, you can see that it must be equal in every direction ; for if it were greater in any one direction than in another, then there would be an unbalanced force, and the liquid at that point would move in the direction of that force. But we are considering a liquid at rest. Hence the pressure must be equal in all directions. For the same reason, too, it must be equal at all points of the liquid. If it were less at one point than at another (leaving out of consideration the effect of weight), there would be motion toward the point where the pressure was less. TRANSMISSION OF PRESSURE. 183 In order to understand how pressure is transmitted according to this law, let us imagine what takes place among the molecules. Remember that the number of molecules is enormously large, and that they are excessively minute, so that we never perceive anything but the average effect of a vast number of them. The pressure of liquids or gases upon the walls of the vessels inclosing them is of this nature, being due simply to the battering of those surfaces by the molecules of the fluids. The molecules strike the surfaces and rebound with equal velocities, but in a reversed or changed direction. This reversal of the direction of their momentum produces the pressure — i. e., the tendency to acceleration — on the walls. If the number of molecules happens to be greater in a given volume near one point of the surface, then the number of molecules striking upon the surface in a unit of time is greater, and therefore the pressure is greater ; or if the velocity of the molecules is increased, each will strike a harder blow, and thus the pressure will be greater. If the pressure is increased at any point of the liquid, as by pressing harder on the piston a b, in Fig. 83, then the molecules become more crowded together at that point, and therefore strike harder against their neighbors, and these in turn against theirs, forcing them back in all directions until the pressure is equal everywhere. If you think of the pressure always as caused by this battering or bombarding of the molecules, and of its transmission through the liquid as due to the jostling of the molecules against one another, you will find it easier to comprehend many of the phenomena. strument attached to each of the holes, the same pressure will be indicated. If the finger be placed over the end of the water-faucet, the jet can be made to play equally in any direction. Through holes in the garden hose the In the case of liquids and gases, we have to deal with pressures distributed over considerable areas. Hence, when we wish to be definite, we must speak of the amount of force on a unit area. This is called the intensity of the pressure, or more often merely "the pressure." The total pressure on any surface will then be equal to the intensity of the pressure multiplied by the area of the surface. For instance, if the intensity of the pressure is 5 pounds per square inch, and the surface acted upon is 10 square inches, the total pressure is 5 x 10 = 50 pounds. This is clear when you think that the pressure depends only on the number of particles battering the surface, which would naturally be twice as great with twice the surface, three times with thrice the surface, and so on. the vessel full of shot (Fig. 20, page 73), you can understand that the upper layer would press upon the second with a force equal to its weight, the second on the third with a force equal to the sum of the weight of the first two, and so on. Imagine now the shot to be liquid molecules flying about in all directions, and thus perfectly free to move. You will then see that the particles will press against the side at any point just as hard as they press downward at the same level ; that is, the intensity of the pressure will be the same on the side of the vessel as in a downward or any other direction. Where the depth is twice as great, the intensity of the pressure will be twice as great, etc. ; that is, the intensity of the pressure is proportional to the depth. The greater intensity of pressure may be pictured as due to a greater bombardment of molecules. This arises from the compression of the liquid, which, although slight, is enough to bring into each unit of volume of the liquid an enormous number more of molecules, and thus to produce the increased number of blows on the unit of surface. reason, divers do not care to descend more than a hundred feet. Glass bottles, empty and tightly corked, are often let down with cords at sea, and the pressure is generally sufficient to crush them at comparatively slight depths. If the bottles do not break, the corks are driven in or water is forced through the pores. When a ship goes down at sea, her timbers are seldom seen again. By reason of the great pressure, capillarity, diffusion, etc., the pores of the submerged wood become filled with water instead of air. Hence, since the solid portions of wood are denser than water, the sunken vessel can not rise. The Intensity of the Pressure does not depend on the Form of the Vessel, but only on its depth ; for, if any molecule is pressed upon, it transmits the pressure in all directions. If the pressure of the first layer is transmitted to any one molecule of the next, then such molecule will jostle about until all the molecules in that layer have the same pressure. For the transmission of pressure, then, it is merely necessary that there should be some communication, however small, between successive layers. Thus, suppose Fig. 85 to represent a cavity in the ground filled with water. The pressure at any point C will be the same — whatever the number or size of the various parts of the channel A B communicating with B— and will depend merely on the vertical depth of C below the surface. Further, the pressure on every unit of area at the same level is the same. This is true only when water is not flowing through A B, but is standing still in the entire cavity ; otherwise, friction makes some difference as in all cases of motion. The pressure on a unit area at C, then — say on one square foot — would be just the same as if a straight pipe, FlG- 85-— PRESSURE PROPORTIONAL one square foot in section, passed T° DEPTH> directly upward from C to the surface and were filled with water. The pressure on one square foot at the bottom of such -a pipe would be 62-5 pounds for each foot of depth— i. e., in all 62-5 x depth, for one cubic foot of water weighs about 62-5 pounds. Hence the following rules : To find the average intensity of pressure on any rectangular plane surface, multiply depth d' of middle of surface by 62-5— i. e., find 62-5 X d'. If the liquid be other than water, use instead of 62-5 the weight in pounds of a cubic foot of the liquid. What would be the pressure per square inch at the bottom of a column of mercury 30 inches high, mercury being 13-6 times as dense as water? The cubic foot of mercury would weigh 13'6 x 625 pounds = 850 pounds. The pressure square inch. How high a column of water would be necessary to produce the same pressure per square inch t As mercury is 13'6 times as dense as water, a column of water 13-6 times as high would be necessary to produce the same pressure — i. e., 136 x 25 = 34'0 feet. It follows from the statements of this section that any pressure may be measured by the vertical height of a column of liquid which it will sustain against gravity. has been shown, it follows that if m n represent a sheet of metal or H any substance in a mass of liquid, FIG. 86.— METAL PLATE UNDER then m n is pressed from each side WATER. wifh equal force. If mn happens from the opposite side. This may be accomplished by the arrangement shown in Fig. 87. The ground glass attached to the string fits the lower surface of the tube closely. Hold the plate up by the string against the tube, and thrust the whole nearly to the bottom of the water. Then let go the string, and the upward pressure will hold the plate against the tube. If the tube be raised, the pressure will gradually diminish, until near the top it becomes too slight to support the weight of the plate, which, therefore, drops off. Hold an empty bpttle neck upward in the hand and press it down in water. You will perceive very much better than by the foregoing experiment how much pressure there is upward on the bottom of the bottle, and how the pressure increases as you The Upper Surface of a Liquid APPARATUS. at Rest is level.— If C P D (Fig. 88) be the surface of a liquid standing in any receptacle, and not level, then any point P will at once begin to move, for it is acted upon by its weight in the direction W. This force may be resolved into two components, A and B, the latter perpendicular to the surface at the point, and therefore balanced, the other tangent to the surface, and thus in a direction in which the particle P can freely move. Such action will continue until no point is higher than any other, and the surface thus becomes level. greater height A on one side than B on the other. At any point, the partition will receive a greater pressure on the A side than on the B side, because of the greater depth of liquid. Make a hole through D E at any point D below B. Owing to the greater pressure on the A side, the liquid must be forced into the B side, and this action will continue until the pressure from A toward B and that FIG. 89.-CHANGE OP LEVEL from B toward A are equal. But this can be only when the depths of liquid are the same in both sides. Hence, when the liquid is at rest in the two communicating parts of the vessel, both surfaces must be at the same level, F G. This is obviously only a special case of the principle explained in the foregoing paragraph. for tubes in which friction interferes with the free flow of the liquid. The Spirit-Level is an instrument used by surveyors, carpenters, masons, and others, and in scientific work by physicists and astronomers, to adjust lines or surfaces. It consists of a glass tube nearly filled with alcohol, or a mixture of alcohol and ether, so as to leave sufficient air to form a small bubble. The tube is then sealed, and mounted in a suitable wooden or metal case. not level. Hydraulic Press — Let A B and D G, Fig. 92, be two upright cylinders communicating by a small tube C, and containing water or other liquid. Let A and E be pistons working without leak in the cylinders. Neglect for the present the effect of friction and the weight of the liquid. Assume the area of A to be one square inch, and that of E to be one hundred square inches. Suppose that A is forced down one inch. Then E must rise just -^ inch ; for by forcing down A one inch, one cubic inch of liquid is forced into D, and E must rise sufficiently to admit this cubic inch, or, as its area is 100 square inches, it must rise ^-J-g- inch. Then, by the principle of conservation of energy, if a load of 1 pound is put on A and descends through 1 inch, it will be just capable of moving E up yi-g- of an inch, if its load is 100 pounds. In general, the total force produced by E is to that exerted upon A as the area of E is to that of A ; for let s be the distance through which A descends, and / the load upon it, and let S be the height through which E rises, and F the load upon it. Then / X s = F X S, fs being the work done by /, and FS the work done against F .-. F : / = s : S. But if a is the area of A, and e that of E, it may be shown as above that s : S = e : a .-. F : /= e : a. That is, the forces are proportional to the piston areas. This arrangement, then, constitutes a machine by which we gain a mechanical advantage similar to that of the lever. We may, by making a small force work through a long distance, produce a great force which will do an equivalent amount of work through a short distance. Such is the Principle of the Hydraulic Press, which, by the use of levers and a small piston on the pump, and of a large piston at E, is made to give total pressures of many tons. It is extensively used for lifting exceedingly heavy weights, for compressing cotton and hay into bales, for extracting the juices from cotton-seed, etc. Fig. 93 illustrates a hydraulic press of great power. By inspecting a railroad car, you will see that the wheel is firmly attached to the axle and turns with it, the bearing being on a prolongation of the axle outside the wheel. The wheel is secured in place upon the axle by making the latter about O'Ol inch larger in diameter than the corresponding hole in the wheel, and forcing it in by great pressure. When thus joined, they hold together almost as solidly as if of one piece of metal, and are said never to come apart in use. The axle is suspended horizontally between C and D by a chain from the carriage E. The wheel is held in place at the end of the axle at D, and the press set to work. The pulley G is driven by a belt from a steam-engine, and works the pump A F. This forces oil, under great pressure, through the small tube B, into the rear of the cylinder H, thus driving out the large piston P with a total pressure equal to the area of its section mul- tiplied into the intensity of the oil-pressure as indicated by a gauge. Machines of this sort are in use which can produce pressures of 200 tons. They are employed, as well, for forcing the great driving-wheels of locomotives on to their axles. In Fig. 94 is shown another into bales for transportation. The cotton is fed in at A, near the top. When the tall receiver is full, the piston, just fitting the receiver, and seen through an experiment as this : EXPERIMENT. — Into a water-tight cask fasten a small tube (of glass or eighth-inch gas-pipe, or even a thick-walled small rubber tube) rising to a height of 10 feet or more above the cask. Fill the cask with water, and then pour water into the tube. Although the cask is very strong, it will be burst by the internal pressure when the water-column is only a few feet high. Of course, the weight of the water in the column would be entirely insufficient for this. But the pressure on every square inch of the interior of the cask is that due to a water-column of this height, and it depends only on the height, and not at all on the size or shape of the column. the rock in fragments. Draw a diagram illustrating this. QUESTIONS.— State the hydrostatic law of the transmission of pressure. Describe the experiment illustrating it. How is liquid pressure and its transmission explained on the molecular hypothesis ? What is meant by the intensity of liquid pressure ? By total pressure ? In a large, closed vessel, full of water, a pressure is exerted on a square inch, at one point, of 10 pounds ; what will be the pressure on a surface of a square foot anywhere else in the vessel, neglecting the weight of the liquid ? Suppose a tank to be full of water ; is the intensity of the outward pressure on the side of the tank the same for all points in a horizontal line ? In a vertical line ? Why ? According to what law does the intensity of the pressure increase with the depth ? Illustrate by the tumblerful of shot. Give the rules for finding the intensity of water-pressure at any depth. For finding the average intensity of pressure upon a given surface. For finding the total pressure on that surface. If the liquid be something other than water, how are these rules changed ? Show by experiment that in a mass of water there is upward as well as downward pressure. Show that there is pressure in all directions. Why does the surface of water assume a " level" ? Is the surface of water at rest truly plane ? If not, what is its shape ? No matter what the size or shape of a body of water may be, its surface has the same level throughout— that is, it is equally distant at every point from the earth's center. Accordingly, the surface of the ocean is spherical ,' and this ive know to be the case from always seeing the mast of a vessel approaching in the distance before we see the hull. The convexity is so slight, however, that in small bodies of liquid the curvature is imperceptible, and we may consider their surfaces as perfectly flat. Show why water in communicating vessels stands at the same level. Would this be true for vessels of unequal sizes, but so small that capillarity affects them ? Describe the principle and use of the Spirit-level. Explain the principle of the Hydraulic press. If the large piston's area is 200 inches and that of the small one 045 inch, how much is the pressure on the large piston for 1 pound on the small one ? Suppose the small piston is worked by a lever of the second order, with a leverage of 10, and a power of 100 pounds is applied at the lever end, what will be the lifting force on the large piston, neglecting friction, etc. Suppose the press worked thus by a man, how much gain of work is there over what the man can do ? What is the kind of advantage gained by using the press ? How much is the gain ? Deduce the law of action of the press by applying the principle of the conservation of energy. By means of the law of hydrostatic pressure. What are some of the practical applications of the press ? Describe the wheel-press ; the cotton-press. Explain the experiment of bursting a cask by a small weight of water. What similar effect is produced in nature ? A Body submerged in a Liquid appears to lose a part of its weight, the amount lost being equivalent to the weight of an equal bulk of the liquid. This is called, from its discoverer, the Principle of Archimedes. EXPERIMENT. — Tie a string to a stone. Hold the end of the string in your hand and lower the stone into water. Notice that when the stone begins to enter the water it appears lighter in weight, and that it continues to lose weight more and more as you lower it until it is all immersed. It then appears of the same weight, whether just under the surface or at any greater depth. Instead of a string use a rubber band, and notice how it shortens as the stone goes under water ; or, better still, attach the stone to a springbalance. A stone so heavy that you can hardly lift it in the air can be easily moved under water, for its apparent weight will be only half or two thirds as much as its real weight. When under water, the body must, of course, thrust aside, or displace, a volume of water equal to its own bulk in order to make room for itself. The apparent loss of weight is equal to the weight of water displaced. This may be experimentally shown as follows : OF ARCHIMEDES. Let A (Fig. 95) be a tin vessel open at the top, and B another which exactly fills A but which has a water-tight top soldered upon it and lead enough inside to make it sink. Hang them upon a springor equal-arm balance and read the balance. Then lower B into water until it is wholly submerged, so that the water surface is at C D. The balance will read less, showing that B has apparently lost weight. Pour water into A until it is just full. You will have added a volume and weight of water exactly equal to that displaced by B. The balance will be found to read the same as before B was immersed. Hence the apparent loss of weight of B is just equal to that of its own volume of water. The same experiment may be tried with any other liquid. This loss of weight is apparent, not real. The cause of the difference is not that the attraction between B and the earth is lessened, but that B is pushed upward by another force which partly counterbalances its weight. This lifting force is due to the pressure of the liquid, and is called the Buoyancy of the liquid. The downward pressure of the liquid on the top of B is that corresponding to its depth. The upward pressure on the bottom is that corresponding to its greater depth, and is therefore greater than the downward pressure, so that the resultant pressure is upward. Suppose the body were a cube in water with its sides vertical. The downward pressure on the top would be 62'5 x area x depth of top. The upward pressure on the bottom would be 625 x area x depth of bottom ; but area of top = area of bottom, and the depth of bottom is greater than that of the top by the length of the side. Hence pressure on bottom— pressure on top =• 62-5 x area x length of side. But area x length of side = volume of cube, and therefore 625 x : area x length = weight of water equal in volume to the cube. The buoyancy is then equal to the weight of an equal the buoyancy will not vary with the depth, since it depends only on the difference of depth of the top and the bottom of the cube, which is always the same, and on the weight of a cubic foot of water which changes but slightly with the distance below the surface. Liquids denser than water will produce a greater, those less dense a less, buoyancy. For such, instead of 62'5 we must write their weight per cubic foot. A similar proof holds for bodies of any form, since they may be regarded as made up of a large number of very minute cubes, to each of which this demonstration will apply. Floating Bodies. — If a body floats when put into water, it displaces a weight of water just equal to its own weight. Place any substance, for example, a piece of wood, in water ; you will see that part of it is beneath and part above the surface. In order that it may float, the body must FLOATING BODIES. 195 be buoyed up by a force equal to its weight. But the buoyancy is equal to the weight of the water displaced by the immersed portion, as shown above. Hence, when floating, a body must be displacing a weight of water exactly equal to its own weight. Any solid or liquid less dense than water— e. g., oil — if entirely immersed in water will be buoyed up by a force greater than its own weight. Why f It will therefore tend to rise through the water and float on top. Warm water is less dense than cold water, therefore it will tend to rise in currents through the cold water. In a glass vessel heated at the bottom, you can see these currents. Cream is less dense than milk, and therefore rises. It is to be noted that we speak of these things as rising, although they really do not rise of themselves but are forced upward by the upward pressure due to the excess of weight of the heavier liquid surrounding them. With the lungs full of water or entirely empty of air, the human body is probably slightly denser than water. When the lungs are full of air, it is less dense than water, so that it will rise to the surface without effort on the part of a swimmer. But the head is more dense than other parts, so that some slight effort is generally necessary to keep the head at the surface. In swimming in the usual position, more of the head is kept out of water than the buoyancy can sustain. Hence, effort is necessary for this purpose as well as for propulsion. In floating on the back with barely just enough of the face out for breathing, no effort is required except a very slight one with the hands to preserve the proper position of the body. The knowledge of how to float thus upon the back with very little effort and to breathe when the head is in the troughs between waves, might save many lives in accidents on the water. Notice some time, when bathing in shallow water, how light the body appears if wholly immersed, and how fast it seems to grow heavy as you rise out of the water to a standing posture. This will easily convince you of the great waste of effort you would make in swimming or floating if you were to try to keep out of water more than just enough of the face to enable you to breathe. Density, or Specific Gravity. — Application of the Principle of Archimedes is made to determine the relative densities of bodies. Density is the mass per unit volume. In scientific work, the density is expressed in grammes per cubic centimetre ; that of water is almost exactly one gramme per cubic centimetre. In engineering and commercial worK, densities are not usually stated in units of mass, but the density is given relatively to that of water taken as a standard. This relative density is called Specific Gravity ; it is more properly Specific Density, or merely Density. By specific gravity, then, is meant the ratio of the mass of any volume of the given substance to the mass of an equal volume of pure water at a standard temperature. As the mass of a cubic centimetre of water is 1 gramme, the specific gravity of a substance referred to water, and its density in grammes per cubic centimetre, are numerically the same. Methods of measuring- Specific Gravity — Weigh the body whose specific gravity is to be determined in air, and then when hung in water, as in Fig. 97. The difference in weight will be the loss of weight in water, which is the weight of an equal bulk of water. Divide the weight in air by the loss of weight in water. The quotient will be the specific gravity. To find the specific gravity of a liquid, like a solution of salt, weigh a glass - stoppered bottle when empty and dry, again when completely filled with the liquid, and a third time when Subtracting the weight of the bottle when empty from each of the other weights, will give the weights of equal volumes of the liquid and of water. The quotient of the first by the second will be the specific gravity desired. A similar method with the bottle may be used for solids. The Hydrometer. — The specific gravities of liquids are also determined readily, when very great accuracy is not required, by means of the Hydrom'eter, one form of which is shown in Fig. 98. SPECIFIC GRAVITY. side of this tube is a paper scale, A B. When the hydrometer is immersed in water, as shown in the figure, it settles to such a depth that the reading on the scale at the water surface B is 1. If it is immersed in a less dense liquid, it will sink deeper, and the reading at the liquid surface will give the specific gravity of the liquid referred to water. If it is immersed in a liquid denser than water, it will sink less deep, and the reading will again give the specific gravity of the liquid. Certain hydrometers are graduated to give specific gravities directly ; some, with an arbitrary scale ; and others, for special purposes, such as testing milk, showing the strength of an alcoholic mixture, etc. The depth to which the hydrometer will sink in the pure article being known, any different result, when a liquid is tested, indicates adulteration. Flow7 of Water. — Let A B (Fig. 99) be any reservoir of water kept at a constant level A. Suppose a pipe to lead from it at 0 along to D E F G L. Let D Hy E I, etc., be open vertical glass tubes. At first suppose D L to be a straight uniform horizontal pipe. Now, if this is closed at L, the water will flow out of C until the pipes D H, E I, etc., are all filled up to the level H IJ K, which is the same as A. But if L is opened, the water in the glass pipes will drop to some such points as H', I', J', K', although A remains the same. Why ? The heights of liquid D H', etc., are supported by, and thus measure, the pressures in D L at the points D, E, F, G. When there is no flow, the liquid is at rest, the pressure must be the same throughout D L, and the heights D H, E I, etc., must all be the same. When the water is flowing out at L, it has to overcome friction on the sides of the tube and upon itself. If any of the vertical pipes were removed from the pipe D L, the water would issue from the opening as a jet or fountain, which would rise as high as the water formerly stood in the pipe. For instance, if E I were removed, the fountain at the point would rise to the height I if L were closed, or to I' if L were open. This statement, however, of flow through the pipe C D E required to supply the quantity escaping at E, and also the friction of the orifice, would somewhat reduce the pressure, and hence the height of the fountain. At L the pressure is only such as to give the water the energy which it acquires on leaving L. At G the pressure must be greater than at L by an amount necessary to do the work of driving the water through G L against the friction. At F it must be greater still by the amount necessary for the work in F G, and so on back to the source C. The resistance to flow through pipes is due partly to friction, partly to other causes ; it increases with increase in length of pipe, roughness of interior, number of joints, number of bends or turns, angle of bends, number of irregular enlargements or contractions of pipe, and rate of flow. It diminishes with increase of diameter of pipe proportionally to about the fourth power of the diameter. Similar statements apply to the flow of gases through pipes, as in ventilating apparatus. These laws find very important practical application in water-supply and sewerage systems, in heating and ventilating apparatus, in steam piping, and in hydraulic work generally. Water in the Soil. — Water is also continually flowing through the soil, in some places along regular underground channels, but more generally in a steady flow or percolation. Fig. 100 may serve to give some idea of this. Let A B C D represent the surface of the ground shown in a vertical section, and suppose the soil to be a uniform gravel or sand, sloping off to a lake at D E. Then the soil would be generally found to be filled with water below a certain depth indicated by the shading below F G H I D. This water FLOW OF WATER. 199 surface would be somewhat definitely marked, but, of course, not perfectly sharp, as the soil above it would be damp. The water below it would be continually flowing in a mass toward the lower level, but the flow would be quite slow, owing to the resistance to flow through the soil. The source of this water is the rain falling upon and soaking into the soil, and the surface F G I is lower after dry and higher after rainy times. Most soils are not uniform, but contain ledges, or strata of clay, sand, or gravel. These strata greatly modify the actual distribution of water. Artesian wells, intermittent springs, etc., owe their action to such peculiarities of soil formation. a hole be dug, as at B W, until it is below the water surface, it will contain water up to that surface, forming a Well. If the well is so deep that the groundwater surface is never below its bottom, the well will never be dry. QUESTIONS. — What is meant by the buoyancy of a liquid ? How much does a body immersed in water appear to lose in weight ? How much would it appear to lose in mercury ? In any other liquid ? In any other fluid ? Show this by experiment. Describe an experiment to prove the principle of Archimedes. Prove the principle for a cube immersed in water by means of the law of hydrostatic pressure. Prove it for a body of any form whatever. Why does a piece of wood tend to rise when wholly immersed in water ? With how much force ? What enables some objects to float ? How much liquid does a floating object displace ? Why will iron float on mercury but sink in water ? Why will oil float on water but sink in alcohol ? About three quarters of the mass of the human body is water ; of the remaining parts much is more dense than water. How, then, is it possible that the body, on the whole, is less dense than water ? If a person is about to dive and wishes to return as quickly as possible to the surface, why should he thoroughly inflate his lungs ? How does your experience in rising out of water illustrate the buoyancy of liquids ? Define Density ; Specific Gravity. Why are the density in grammes per cubic centimetre and the specific gravity referred to water numerically the same ? What is the density of gold ? Of water ? Of air ? Describe a method for find- ing the specific gravity of a solid ; of a liquid. Given a block of iron 1 inch long, 2 inches wide, and 3 inches high; how could you find its density without immersing it in water or wetting it ? How should you suppose the density of a gas might be determined ? A piece of unknown material whose weight is 23'25 grammes is found to weigh 20 "15 grammes in water. What is its specific gravity ? What is its density ? Refer to the table on page 197 and see what the substance probably is. What is the weight of a cubic foot of water ? Of iron ? of air ? What is the volume in cubic feet of a ton of water ? Of a ton of iron ? Describe the flow of water through pipes by means of Fig. 99 (page 198). What factors affect the resistance of pipes to the flow of liquids ? Why is a pipe of twice the area of section more than twice as good ? Why is a straight pipe better than a crooked one ? A short one than a long one ? A large one than a small one ? One with a smooth interior than one with a rough interior ? One with few joints and turns than one with many ? Do these statements apply also to chimney-flues ? To ventilating flues ? Would a chimney u draw " well out of a room into which no air could enter ? Where do you suppose the air enters a room when all the doors and windows are closed ? Describe the simplest case of the distribution and flow of water in a uniform sand-hill. If in Fig. 100 there were a horizontal layer of clay across the hill one quarter way up from the lake, where should you expect to find springs ? GASES AND THEIR PROPERTIES. Gases have Weight. — We easily perceive the weight of most solids and liquids because they weigh more than the air displaced. You will see, however, on reflection, that we can not weigh water in water, as the quantity to be weighed would be buoyed up by a force equal to its own weight. For a similar reason we are not sensible that air has weight, for we ordinarily weigh bodies in air, and air weighed in air would appear without weight ; try the following EXPERIMENT.— Hang the hollow globe of Pig. 101 on one arm of some moderately sensitive balance, and counterpoise it by sand or any weights in the other pan. Then take off the globe and exhaust the air with the air-pump or by sucking it out with the mouth. Close the FIG. 101. stop-cock and again hang the globe on the weight. A litre of air weighs only 12 grammes at ordinary temperatures and pressures, while a litre of water weighs 1,000 grammes, so that the density of air is only about ^, or roughly -nf^, of that of water. Atmospheric Pressure. — The earth is surrounded on all sides by a layer of air several miles deep called the Atmosphere. As this air has weight, it must press down upon the earth's surface and everything on the earth just as the water does on the .ocean-bottom and on all submerged objects. At sea-level, the pressure of the air is in all directions about 15 pounds to the square inch. We may show the existence of such pressure by several experiments. EXPERIMENTS. — Fig. 102 illustrates the " Magdeburg Hemispheres " — hollow metal hemispheres, with their edges carefully ground and greased. You will then find it very difficult to pull them apart in any direction. Why I Because the atmosphere, owing to the pressure produced by its weight, is forcing them together on all sides. Over the top of a glass vessel like that shown in Fig. 103, stretch a piece of thin sheet rubber. Place the glass upon the plate of the air-pump. The rubber will be flat. Exhaust some of the air. The rubber will begin to bulge inward. Why ? Because the atmosphere presses down upon it. But this was also the case before the air was removed ; why did the bulging not occur then? Because the pressure was balanced by the upward pressure of the air beneath. Instead of the glass shown, a lamp - chimney, with a rubber stopper in one end and the sheet rubber PHERIC PRESSURE. same result will be reached if the rubber surface is downward, sidewise, or in any position, showing that the atmospheric pressure is exerted in all directions. If the palm of the hand is put in place of the rubber sheet, it becomes bulged inward when the pressure is removed from beneath it. break in with a snap. Why 1 Over the top of an argand chimney, or any other glass tube, tie a bit of thin sheet rubber. Place the whole sidewise under water and fill it. Then invert it as shown in Pig. 104. The rubber is drawn in more and more the higher it is above the water outside the tube. When the rubber is level with the water outside, it is flat. Why f Because the water column below the rubber transmits the atmospheric pressure to the under side of the rubber, and the upward and downward pressures are equal. But as the tube is raised, the water column itself balances part of the atmospheric pressure, so that the upward pressure on the under surface of the rubber is less than the downward pressure on the top. Put a tumbler under water and fill it. Then draw it out bottom upward. Notice what happens and give the reason for it. Does the tumbler feel heavier f Why ? How much ? A glass tube A B (Fig. 105) is closed at both ends by stoppers. Through the lower stopper passes a small tube D C drawn out to a fine open point at C. Suck out as much of FIG. 105. the air by the mouth at D as you can. Then close D with the finger, thrust the lower part of the apparatus under water, and observe what occurs. Explain the action. The Barometer. — Melt together in the gas-flame the end of a clean, dry, glass tube, three feet long and one eighth to one fourth inch inside diameter. Fill it with mercury. Bubbles of air will adhere all along the inside of the tube. To get rid of these, leave a quarter of an inch of the tube at the open end empty. Put the finger over this end and turn THE BAROMETER, the tube into a nearly horizontal position, but with the closed end a little higher. The large bubble will run upward slowly toward the closed end, collecting the smaller ones on its way. Then raise the open end, and the bubble will run back. Repeat this operation several times, until most of the bubbles are removed. Next fill the remaining space with mercury, put the finger over the open end, and invert the tube into the position shown in Fig. 106, where B is the closed end R F is called a Barometer. The mercury in the barometer will fall at once to some point C. Measure the height A C from the surface in the dish. It will be found to be, on the average, at the sea-level, about 30 inches (from 28 to 31, according to the condition of the weather). This experiment is called, from its discoverer, Torricelli, the Torricellian experiment. Repeat with a different tube, and A C will be found the same, except for variations due to imperfect removal of air, capillarity, etc. Why does the mercury not fall to A ? Use a much longer tube ; A C will be the same. Use a tube less than A C in length, and the mercury will remain up to the top. Compare this with the experiment of Fig. 103, and with the tumbler experiment (page 202). The atmospheric pressure, then, is transmitted through the mercury in the dish to the bottom of the tube, and there presses upward with a force sufficient to balance the downward pressure of a column of mercury of a height A C— about 30 inches. The barometer, therefore, measures the atmospheric pressure, and hence its name (weight-measurer). This pressure at sea-level (see example, page 186) is about 14-7 pounds on each square inch of surface. If the atmospheric pressure will balance a column of mercury 30 inches high, it will sustain a water column of 34 feet, for these two columns produce equal pressure (see example, page 186). To balance least 34 feet instead of 30 inches long. If, instead of a straight tube inverted in a dish of mercury, a tube be bent into the second form shown in Fig. 106, the end F being closed and the short end open, the mercury will stand with a difference of level E D, equal to A C of the other tube. The space above the mercury in B C and F D is called a vacuum (empty space). If the experiment were perfectly performed, it would contain nothing but a minute amount of the vapor of mercury. A perfect vacuum would be a space containing nothing ; but such a condition can not be reached. All that we can arrive at is a space containing only a very minute amount of gases or vapors. Uses of the Barometer. — The instruments ordinarily sold as mercurial barometers contain a tube like one or the other of those shown in Fig. 106, carefully filled with mercury, all air being removed. A scale along the upper part of the tube marks the height of the mercury. This height varies from time to time, because of changes in the atmospheric pressure accompanying changes of weather. In general, a rapid or considerable falling of the mercury accompanies a storm and a rise of temperature ; while a considerable rise is usually accompanied or followed by fair and cooler weather. The weather can not, however, be predicted closely from readings of the barometer alone. Rapid and extreme changes of barometer generally indicate and accompany violent winds. The barometer is also used to measure the heights of mountains, as explained on page 225. The Aneroid Barometer. — An instrument known as the Aneroid (without moisture) Barometer is very convenient for many purposes. It is light, compact, and easily carried, and thus forms a desirable substitute for the mercurial barometer, which is awkward and heavy, although more accurate. A flat, thin-walled, circular metal box (two to five inches in diameter), with a corrugated surface, is hermetically sealed, after the air has been exhausted from within it, in order to prevent the indications from being affected by the varying pressure of this air under change of temperature. When the atmospheric pressure increases, the sides of the box are thereby forced farther inward ; and when this pressure is lessened, they spring outward, the amount of motion being proportional to the change of pressure. To indicate this motion, a mechanical arrangement of levers, etc., is connected with the box in such a way that the compression and expansion move a pointer playing over a graduated dial. From this dial the pressure may be read directly. To understand fully the principle of the aneroid, which is often carried in the pocket to determine heights above sea-level, the pupil must examine an instrument for himself. QUESTIONS.— Prove that gases have weight. Why does the atmosphere exert a pressure on objects within it ? In what direction is the atmospheric pressure ? What is illustrated by the Magdeburg hemispheres. Describe several experiments illustrating the pressure of the atmosphere. Do all gases transmit pressure according to the same law as liquids ? Do all fluids? What is a fluid? Describe the filling and inversion of the tube in the Torricellian experiment. What keeps the mercury from falling inside the tube to the level of the mercury outside ? If a barometer-tube were placed under the receiver of an air-pump and all the air pumped out, where would the mercury stand in the tube ? Why ? How high, on the average, does the mercury stand in a baror.ietertube ? Why does it vary in height ? What is meant by a vacuum ? Has a perfect vacuum ever been attained ? What more does the ordinary form of barometer possess than the single tube and cistern represented in Fig. 106 ? Enumerate the uses of the barometer. Explain the principle of the aneroid barometer. GASES. Gases are compressible. — The pneumatic syringe, shown in Fig. 107, is a glass tube in which a tight-fitting piston can be pushed down. Air or other gas may be inclosed between the piston and lower end of the tube, with no chance for escape. Push down the piston, the air is reduced in volume — i. e, is compressed. pressing the air. Try the same experiment with mercury. Law of Compressibility. — Fig. 108 shows a vertical glass tube bent at the bottom, open at the end B, and closed at D. The tube is at first full of air or other gas. A scale is placed along each branch. A little mercury is then poured in at B, thus separating the air in the closed branch, D C, from the outside air, so that no air can enter the closed branch or escape from it during the experiment. The mercury stands at nearly the same level at A and C, and therefore does not exert any pressure on the inclosed air. The air in D C is now under the pressure of the atmosphere at the time, for the atmosphere is pressing down on the mercury at A, and the pressure is transmitted through the mercury to the gas at C. This pressure may be assumed, for our experiment, to be equal to that of about 30 inches of mercury. Read now the heights of the mercury at A and C on the scale between the tubes. They will be nearly the same. Read also the height of the mercury at C on the scale at the right of D C. This scale is numbered from the top D downward, and measures off the volume of the air between D and the top of the mercury. Suppose, then, that A and C read 2 on the middle scale, and C reads 42 on the volume scale. Then the pressure of the inclosed air is 30 inches of mercury, and the volume is 42 units. Pour in more mercury until the mercury in the open arm stands at a height of 30 inches above that in the closed arm — for instance, suppose that the first height is 46 and the second 16, on the middle scale, and that the reading in the closed arm is 21 on the volume scale. Then the volume has been reduced to 21. What is the pressure? The mercury column is exerting a pressure of 46 — 16 = 30 inches, by its own weight. In addition to this, it is transmitting the atmospheric pressure of 30 inches. Hence the pressure on the gas at the level of the mercury in the closed arm is 30 + 30 = 60 inches. The pressure, then, has been doubled, and the volume thereby halved. Pour in more mercury until A. stands 60 inches above C, Suppose that the pressure scale then reads 795 inches and 19'5 inches, and that the volume scale reads 14. Then the mercury-pressure is 795 — 195 = 60 inches, and the total pressure is 30 + 60 = 90 inches. The volume is 14. The pressure has then been trebled, and the volume reduced to one third. In general, it will be found that, however much mercury is poured in, the volume of the compressed air will be inversely as the pressure upon it, if we keep the air at a constant temperature. The law of the compressibility of gases, then, is as follows : upon it. This law is very nearly true for all gases, but there are slight variations from it. It is called the law of Boyle, or sometimes the law of Mariotte, from the names of its discoverers. The apparatus of Fig. 108 illustrates the law only when the pressure is greater than that of the atmosphere. Fig. 109 shows an apparatus for proving the same law for smaller pressures. Then a little air is allowed to bubble up into the tube through the mercury, collecting above it as shown at A B. EXPERIMENT. — Push the tube down until the mercury within it stands at the same level as that outside. Then the pressure on the gas is equal to that of the atmosphere, or 30 inches of mercury. Measure the volume of the air by read- FlG 109 ing off from a scale beside or upon the tube the distance from A to the mercury surface in the tube. If, now, the tube is lowered, the air will be compressed. If it is raised, the air will expand. Raise the tube somewhat. Measure the volume A B from A to the top of the mercury column (left-hand position in the figure) ; also the distance from B to E, the mercury surface in the cistern. The pressure of the air is now less than that of the atmosphere by the pressure of the mercury column whose height is BE; for the atmospheric pressure transmitted from the outside surface of the liquid in E through the mass of liquid and into the tube is balanced in part by the pressure due to the weight of the column B E. The pressure is, then, 30 inches minus B E (expressed in inches). For example, if B E = 5 inches, the pressure is now 30 — 5 = 25 inches. Suppose the first volume was 42, then the present volume will be found to be 50-4. Now, 50'4 : 42 = 6 : 5, and 25 : 30 = 5 : 6. That is, the volume is inversely as the pressure. If the tube be raised still higher, as shown in the second position in Fig. 109, the air will expand further, and the mercury stand at a still higher point, D. Suppose that D E = 15 inches. Then the pressure will be 30 — 15 = 15 inches, or one half the original. The volume will be found to be 84 — that is, double the original. Thus the same law holds ; for the atmospheric pressure, under which we start to go either one way or the other, is no natural starting-point, but merely a pressure which happens to exist at the earth's surface. In all these cases, the pressure exerted by the gasjs of course exactly equal and opposite to the pressure upon the gas. Otherwise, there would not be equilibrium. Gases expand. — We have seen how, by increasing the pressure upon them, we can compress gases. Let us study the effect of removing the pressure. is loose and lies in folds, as in Fig. 110 ; the air inside and outside of it is at the same pressure, that of the atmosphere at the time. Now work the pump. Notice how the balloon swells out more and more as you proceed. What is taking place? the receiver, thus reducing the pressure. The air pressure within the balloon is no longer balanced by that outside, and motion ensues. The air-molecules within the balloon force one another farther and farther apart — that is, the gas expands. FIG. 112. How much does it expand I Stop pumping, so that the pressure on the balloon may be constant. The air in it expands until its pressure inside the balloon is just equal to that outside, allowing of course for any elastic force produced by the rubber if it is stretched. The more you pump, the less the outside pressure, and the more the air inside must expand to reduce The glass bulb F full of air (an inverted test-tube will answer) is placed inside the bottle, with its open end down, and immersed in a shallow layer of water at B. C is a plug closing the second opening in the stopper. On sucking the air out of the bottle by the mouth at the tube E, the air in the bulb will expand, as shown by its bubbling through the water. Expansion will continue indefinitely — that is, a gas will continue to expand as long as we go on diminishing the pressure. Suppose we had a large air-tight box and exhausted all the air from it, so that it was really empty — i. e., was a vacuum. Then suppose we admitted a small bubble of any gas. Even so minute a portion would rapidly expand to occupy the whole box ; and this would be true, however small the amount of gas and however immense the box, provided there were no disturbing forces like gravity. This fact about gases is sometimes expressed by saying that gases tend to expand indefinitely ; by which is meant that they will so expand unless prevented by some external force. has already been illustrated at page 72. By carefully reviewing the statement there made, you will see that it is a necessary consequence of the supposed continual heat vibration of the molecules of the gases. As all gases with which we deal are under some compressive force greater or less than that of the atmosphere, they must all be constantly exerting an expansive or outward force or pressure. Of this we have familiar evidence in the explosive force of air or steam under great compression in air-guns and steam-boilers, as well as in the gases generated behind a cannon-ball by the burning powder, etc. lowing experiment : EXPERIMENT. — Fill with mercury a glass tube an inch in diameter and four or more inches long. Invert it in a vessel of mercury. Introduce into the tube over the mercury enough ammonia or carbonic acid gas to displace nearly all the mercury. Heat thoroughly a small piece of wood charcoal in the flame of a Bunsen or alcohol lamp (see page 230). Cool it by plunging it into the mercury, and then let it float up into the tube. The charcoal will soon absorb a large portion of the gas, and the mercury will rise in the tube. The gas appears in this case to be simply reduced in volume by a peculiar condensing action of the charcoal, and not to be chemically acted upon. It will be given off again by the charcoal upon heating. The preliminary heating was to expel gases already condensed within the charcoal. Gases are also reduced in volume by solution in liquids. If water that has been standing in the air for a while be boiled, it may be found, with suitable apparatus, that a considerable volume of air which was held in solution is given off. If a tumblerful of cool water be drawn from the well or pipes and allowed to stand in a warm room for some time, bubbles of air will be found upon the inner surface of the glass. This is air held in solution by the cool water and given out by it as it becomes warmer. Fish breathe such air mechanically entangled in water. How ? The foam and bubbling of soda and other mineral water is due to the giv- tion under pressure. QUESTIONS.— Describe the experiments showing the compressibility of gases. State the law of compressibility. Describe an experiment proving this law for pressures below one atmosphere ; for pressures above one atmosphere. Why do we find it convenient to start with the atmospheric pressure rather than some other ? Why is it necessary to confine gases on all sides in order to retain them ? What would an unconfined gas not affected by gravitation do ? What is meant by the statement that gases tend to expand indefinitely ? Are all gases with which we have to deal exerting an outward elastic pressure ? How is this pressure explained on the molecular theory ? Suppose a barometertube, with the mercury standing at 30 inches, be sealed up in a glass case full of air into and out of which no air can go. At what height will the mercury stand ? The outside atmospheric pressure can not get at the cistern when thus sealed. Why, then, does not the mercury fall ? What does this illustrate ? Describe experiments illustrating tne expansive pressure of gases ; an experiment showing the absorption of gases by solids. Are gases absorbed by liquids ? How does absorption illustrate the compressibility of gases ? Why is a boiler full of steam at 100 pounds pressure more dangerous — i. e., why does it possess more energy— than if filled with cold water under the same atmospheric pressure ? PUMPS AND SIPHONS. The Air-Pump. — Fig. 11, on page 173, illustrates a simple form of air-pump. The use of this particular form is to remove air from apparatus for such experiments as many already described. The air-pump has, however, very important applications in commercial work, for removing air or other gases from apparatus of various kinds, such as the evaporating tanks in sugar-refining, the condensers of steam-engines, the globes of incandescent electric lamps, parts of ice-making machinery, etc. Air-pumps are of two classes — those whose parts are all solid, and those whose action depends on the use of mercury. The first kind only will be described here, and the common school air-pump will be selected as a type. Pumps of larger size, which are usually run by steam-power, are similar in principle. Fig. 113 shows a vertical section of the pump illustrated on page 173. R is the receiver, N M the plate on which R stands, O the central tube passing through the plate and base to the pump proper, P'. S is a screw stop-cock, When turned forward, it closes the tube at its tween the lower valve b and the piston P will thus be increased. The air will expand to fill this space, and will be thereby re- Hence b will be pushed open into the position b", and will be held open as long as H is moving outward. Thus all the air in the receiver, pipes, and pump below the piston, continues to expand as long as the piston moves. The valve a will be kept closed throughout by its weight and the atmospheric pressure outside. When P stops at the end of the stroke, b" will fall into the closed position b' or b'" by its weight. The return stroke is made by pushing H inward as shown by the arrow in the lower figure. Valve b remains closed. Valve a remains closed also at first, until the air between V" and the piston P'" is reduced to such a volume that its pressure is again equal to that of the atmosphere and just enough more to lift the weight of the valve a. Then, as the piston goes down farther, this air opens a into the position a'", and continues to escape through it until the piston stops at the bottom of the cylinder, when, of course, a closes into its first position by its weight. The operation is then repeated. As H is drawn out again, the air in the receiver opens b when the pressure of the air below P is reduced by its expansion to a little less than that in 0, so that the weight of the valve can be lifted. The receiver air then holds b open and expands into the pump until the out-stroke is completed. Then b closes, the Thus at each stroke a certain fraction of the air is removed. Suppose this fraction to be -fa. Then the first stroke removes fa of the air and 1% remain. The second stroke removes -fa of the remainder — i. e., fa x 1% = Ttju °f the whole. There therefore remains -fa — Tthr or ^/o after the second stroke ; -i70^r, or say -j2^, after the third, and so on. You will thus see that a smaller fraction of the original air is removed each time, and that we can never remove it all. To obviate the difficulty of lifting the weight of the valves which interferes with very thorough exhaustion, automatic arrangements of various kinds are used in specially fine pumps. The Lifting-Pump. — Perhaps the most familiar of the many forms of pumps is that used for raising water from wells, known as the lifting-pump. The glass model shown in the left-hand figure of apparatus numbered 12 (page 173), illustrates clearly its operation. The action of the pump will be work in precisely the same way as those described for the air-pump. Then the upper valve a in the piston, and the lower valve b (fixed in position in the bottom of the pump), close of their own weight. The water can not then escape downward through them, as they and the piston are made watertight. But why does the water stand up to b in the pipe above the surface of the supply W? Why does it not run down and leave the pipe empty — i. e., a vacuum f "Why does the mercury stand at a height of 30 inches in the barometer-tube (Fig. 106)? Why does the water fill the inverted tube Fig. 105 and the tumbler of the experiment on page 202 ? The water is kept up in the pipe by the atmospheric pressure when the pipe has once been filled, provided there is no leak. The atmosphere presses down on the water surface at W, and this pressure is transmitted through the water to the bottom of the pipe and up through the water in the pipe to the bottom of the valve. The valve a is then pressed upward on its under side by the atmospheric pressure less that due to the column of water whose vertical height is from b to the surface of W. It is pressed downward by the atmosphere plus the column above b. Now, push down the handle A so as to cause C to rise, thereby raising P. Call this a forward stroke. As P rises, the water forced up by the atmosphere follows it, pressing open &, which is hinged at one side, and thus keeps the pump full up to the piston. The valve a is kept closed by its own weight and part of the atmospheric pressure. At the end of the forward stroke, P stops and b closes by its weight. Then the return-stroke begins. As b is closed and kept so by its weight and by atmospheric pressure, the water above it can not escape. As P descends, therefore, the water beneath forces a open and escapes through it to the upper side of P. When the return-stroke is completed, P stops and a closes by its weight. A forward stroke is then begun and goes on as before, the water above P overflowing at S. The amount of work done at each stroke in steady pumping is equal to the work required to lift vertically from W to S, against its weight, the mass of water which overflows ; and in addition to do all the work of friction and acceleration. The actual mass of water overflowing is, of course, not lifted from W at that particular stroke ; but the work done in lifting all the water in the pump the short distance through which it rises is equal to that which would be done in lifting the overflowing mass from W to S. What is the source of energy which does this work ? It is the source which acts on the handle A, whatever that source may be — e. g., a man or an engine. It is not the atmosphere or gravity. Without the atmosphere, the liftingpump would not work, for the water would not stay up nnder the valve ; but the atmosphere is not the source of the energy which does the work. The pump does just as much work against the atmosphere as the atmosphere does energy is restored to the atmosphere as is taken from it. All the work (except a little friction) is done on the forward stroke. As this stroke is progressing, the upward pressure on the bottom of the piston is equal to the atmospheric pressure minus the pressure due to the column of water from P to W. The downward pressure on the top of the piston is that of the atmosphere plus that due to the column of water above P. The piston is therefore pressed downward on the whole by a pressure due to the column of water lifted. The force by which P must be pulled up is then equal to its area multiplied by the intensity of the pressure due to a water column of the height P W. The work done at each stroke is equal to this force multiplied by the distance through which P moves. The action of the atmosphere may be regarded as simply holding the water up in the pump and pipe. Cohesion would do equally well if the water cohered, and also adhered to the piston with such force that its own weight would not pull it away. How is the pump filled in the first place ? If the piston and valves work air-tight, we may start with the pump empty — i. e., containing nothing but air down to the level of W. Then, on raising and lowering the piston, this air will be pumped out and the water will follow it up into the pump — that is, the pump will act as an air-pump until all the air is removed, and then it will be full of water and act as a water-pump. If the piston and valve do not work air-tight, some water is poured into the top of the pump. This serves temporarily to seal up the valves and piston so that they will not leak air, as water leaks through small crevices more slowly than air. The pump then works as an air-pump until the water fills it. If the pump leaks through the lower valve or at any point of the pipe below it, air will be drawn in and the water will run out when the pump is not in use. The pump is then said to be " run down." To prevent freezing, the water is often let out purposely by opening both valves or otherwise admitting air. The lower valve is usually provided with a point projecting upward and backward, so that when the piston is forced as far down as possible it presses upon this point in such a way as to hold both valves open. The Limit of Height P W at which the pump can be placed above the level of the supply is about 34 feet, for the pump will not work above the height at which the water can be sustained by the atmospheric pressure. We have seen, on page 203, that this is 34 feet. In practice, however, the lifting-pump will often cease to work at a less height than this, as the atmospheric pressure will sometimes balance only about 30 feet of water. Of course, the greater the height P W, the larger the piston, and the smaller the pipe, the harder the pump works. The piston P is solid and is raised and lowered by the lever A C B through the connecting rod C D. Valves opening upward (usually hinged at one side) are placed at a and b. Assume the pump to be full of water in all the shaded parts. No water is supposed to go above the piston. Let an up stroke of the piston be started. The valve a will close by its weight and that of the water above it, and the water from the supply W will be forced up by the atmosphere through b, which will thus be held open. At the end of the up stroke, the valve b will close by its weight. At the beginning of the down stroke, the piston will force the water out ahead of it, and, as b is closed the tighter by this pressure, the water can escape only by opening a and passing through it into the delivery-pipe H S. This pipe leads off to the point at which it is desired that the water shall be delivered. It may be as high or as long as desired, the only effect of increased length and height being to require the application of more energy at A and greater strength of pump and pipes. The Air-Dome, shown in Fig. 116, is usually connected with powerful force-pumps. Its object is to steady the pressure at which the water goes through the delivery-pipe. Let A B be a section of some horizontal portion of the deliverypipe H S near the pump. A branch pipe turns upward from A B, and upon this is placed the air-tight hollow dome of metal C D E. This dome is full of air. When the pump makes a down stroke, it forces water violently into the deliverypipe, and would thus greatly increase the pressure and give a violent strain to all the piping. The dome reduces this shock, for, as the water is forced violently in at A, it finds the escape into the dome by compressing the air there easier than the violent passage out through B. The sudden rush of water passes partly into the dome, rising there from a FIG 116— AIRlevel C to a higher one D and compressing the air. DOME. As soon as the down stroke ceases, the valve a closes and the compressed air in the dome forces the water out through B, lowering it to its former level at C. This operation goes on at each double stroke. Thus the air-dome relieves the violence of the shock in the pipes beyond it, and to some extent also in the pump and the connecting pipes. It also makes the rate of delivery more uniform, as owing to its action there will be water flowing through B during the up stroke when there would be none The Siphon. — Bend a glass tube, one or two feet long and a quarter of an inch in diameter, as shown at A B C, Fig. 117. Leaving it full of air, dip one end into a vessel of water D and let the other hang out into the air or dip into another dish of water at E. No action will take place. Now take the tube out and fill it with water. Close each end with a finger and dip one into D, the other into E. Water will flow through the tube, from the vessel D in which the water surface is at the higher level, into E, in which it is at the lower level. same results. Why does the water flow ? In the first place, suppose the level of the water in D and E to be the same, and hence no flow to be taking place. The water still fills both sides of the tube up to B. It is retained there by the atmospheric pressure on D and E, and the tube will thus be kept full when once filled, however long either arm, within the limit of 34 feet. Next suppose one surface, E, to be lower than the other, D. Then at the top section B, the pull on the water toward E is that due to the column of water whose height is the vertical distance from B to E, while the pull toward D is that due to the differ- THE SIPHON. ence of level B D. There is, therefore, a resultant pull toward the lower level of an amount proportional to the difference of these two heights, which is F E, the difference of level of the two surfaces. The water will therefore flow from D to E as fast as this force can draw it against the resistance due to friction in the pipe, etc. The siphon requires the atmospheric pressure merely to keep the water together in the tube. If the water had cohesion enough to hold itself together, the siphon would work without the atmosphere. In fact, a short siphon will work under the receiver of an air-pump. The Source of Energy that works the Siphon is gravity, the force being the weight of the liquid. The moving liquid acquires no energy from the atmosphere. As the working force is proportional to the difference of level of the surfaces of the supplying and the receiving liquid, it is evident that the greater this difference of level the faster the siphon will work, other things being equal. The larger the tube, the less the friction and the faster the flow ; but if the tube be very large and the flow slow, air may bubble up into the siphon and stop its action. working. Crevices in rocks sometimes act as siphons and drain underground cavities, giving rise to intermittent springs. In the section shown in Fig. 118, the water derived from surface drainage will rise to the level B L in the reservoir before the crevice begins to discharge it at A. Why f The crevice will continue to drain the cavity until the level is reduced to A L, when the flow ceases. Why 1 QUESTIONS.— Describe the action of the Air-Pump. Would the air-pump work if gases were not self -expansible ? Can all the air be removed from a vessel by a perfect air-pump ? Why ? Describe the construction of the Lifting-pump, its mode and principle of action. Would the pump work if the atmospheric pressure were removed ? What part does the pressure play ? Where does the energy come from which lifts the water ? How much energy must be supplied at each stroke ? Would you think it correct to say that in raising the piston of the pump the atmospheric pressure was partly or wholly removed by that means from the top of the water column and the atmosphere thus permitted to force up the water beneath the piston ? If so, show that the work done upon the atmosphere in that operation is equal to that done by it. If we had a liquid endowed with strong cohesion and adhesion, could it be pumped in vacuo ? May we then say that the atmospheric pressure supplies the place of cohesion in the action of the pump ? What is the average highest limit at which a lifting-pump can be worked above the supply ? Describe the form and action of the Force-Pump. Show how it is only a slight modification of the lifting-pump. Take the case of a well in which the water stands 50 feet below the surface, and suggest some way of pumping the water out. Describe the action of the Air-Dome. What is a Siphon ? Describe its action. Will it work in vacua f To what extent ': Why does it depend upon the atmosphere ? What is the source of energy which transfers the water ? The water at the lower level has less potential energy than at the higher, and after it has become still it has no energy of onward motion ; what, then, has become of the energy expended upon it in the siphon ? Would the water be warmer after passing through the siphon ? Should you expect to detect the difference with the sense of touch ? Why ? Some miners desire to empty a large wooden water-tank, but do not wish to bore a hole in it, and have no pump ; they are at a loss to know how to proceed. What method can you suggest ? Explain intermittent springs. Ascertain what the Tantalus Cup is, and explain its action. DIFFUSION OF GASES. Diffusion through a Porous Partition. — In Fig. 119, B represents a porous earthenware jar, such as is used in some electric batteries. It is inverted, and its open end is plugged with a rubber or cork stopper, through which passes a glass tube, C, opening into the jar and dipping into a colored liquid in D. A large glass jar or wide-mouthed bottle, A, can be held inverted, as shown, over B. Let A be removed and held over a hydrogen generator or jet of illuminating gas. The hydrogen will rise and fill A. Then let A be carefully pushed down over B, as in the figure. Bubbles of gas will at once begin to come up through the liquid in D, showing that the amount and pressure of the forced out through the tube. What has taken place? The hydrogen from A must have passed through the pores of B into the interior. It does so by a process called Diffusion, which is of the same character as the diffusion of liquids described on page 179. But not only has the hydrogen gas diffused through the pores of the jar into its interior, but some of the air from within has diffused outward at the same time. The hydrogen, however, goes in faster than the air comes out. When B was standing in the air before the experiment, diffusion of the outside air .into the interior, and of the inside air outward, was similarly taking place. We did not observe it, because the diffusion each way was at the same rate, the gas being the same, and at the same temperature, inside and out. Thus hydrogen and air diffuse at different rates. EXPERIMENTS. — Remove the jar A immediately after the experiment above. The liquid of D will rise in the tube, for there is now only air outside B, while inside there is a mixture of hydrogen with air. This mixture diffuses outward faster than the air diffuses inward. After all the hydrogen has escaped from B, fill A with carbonicacid gas. This is heavier than air, and will escape when A is inverted, unless the mouth of the jar is kept closed with a cardboard. Invert A over B. The liquid will now be seen to rise in C. The carbonicacid gas diffuses more slowly than air. Gases are thus shown to diffuse through porous partitions. In general, the less dense gases— e. g., hydrogen — diffuse faster than the more dense ones, as carbonic acid. ally, but may in a measure be illustrated thus : Pour a little strong ammonia-water into a shallow dish in a small closed room. This illustrates the free diffusion of gases, as ammonia is a gas, ammonia-water being a solution of this gas in water. When the solution stands open, some of the gas passes off into the air and quickly diffuses through the room. Most odors are gases or vapors diffusing in this way. The diffusion of one gas into another is similar in nature to liquid diffusion. The molecules of each gas, in their free movement, pass off into the spaces between the molecules of the other gas. Why do the less dense gases diffuse faster ? Equal volumes of all gases contain the same or nearly the same number of molecules. Hence the molecules of the less dense gases have the less mass. At the same temperature, the less massive molecules move faster than the more massive ones, and therefore penetrate farther in the same time. Diffusion through Membranes. The bladder will at once begin to be drawn, or rather pressed, inward in a concave form. The hydrogen diffuses outward faster than the air passes in, leaving a partial vacuum. Fill the bottle with carbonic-acid gas instead of hydrogen. Fill a larger inverted bottle with hydrogen and hold it down over the bottle of carbonic acid. The bladder will bulge outward, for the hydrogen diffuses inward faster than the carbonic acid outward, thus making the pressure inside greater than that outside. THE ATMOSPHERE. 223 the earth, and held in place by its own weight. It consists chiefly of four volumes of nitrogen and one of oxygen, but also contains less than one per cent of vapor of water and. a small amount of carbonic acid. Owing to free diffusion and to the stirring action of winds, the atmosphere is a thorough mixture of these gases, the proportions, except of aqueous vapor, being everywhere almost exactly the same, except in confined spaces, such as buildings, mines, etc. As this atmosphere is kept in place by its weight only, the pressure within it must be greater the farther we descend into it from the outside, just as the pressure increases with the depth in a liquid. Indeed, the atmosphere has been likened to an ocean of air. But air is easily compressible, and, of course, the more it is under compression the more dense it is. Therefore, if we were to descend from the outside into the earth's atmosphere, we should find not merely that the pressure was greater, but that the air was more and more dense the farther we descended. Thus, while the water pressure, as we descend into the ocean, would be found to increase proportionally to the depth, and the water to be of sensibly uniform density, owing to its very slight compressibilty — in descending into the earth's atmosphere, we should find the pressure to increase much more rapidly than in proportion to the depth, and the density of the easily compressible air to increase more rapidly also. In other words, if we were to ascend from the surface of the earth, we should find the air growing less dense (or more rarefied), and the pressure lessening more rapidly than in proportion to the height. Owing to this fact, the greater part of the mass of the atmosphere is near the earth, one half of it being probably within three and a half miles of the earth's surface. The upper air is extremely rarefied, and shades off, as it were, very gradually into empty space. determined, for this limit is not well marked ; but it is estimated to be between thirty and sixty miles. It is probable that there are minute perceptible traces of air as high as several hundred miles from the surface. If the atmosphere were of uniform density throughout, the same as that at sealevel, it would be sufficient in volume to cover the earth with a layer only about five miles deep, out of which some of the highest mountains would project. The atmosphere, or more properly the air, does not stop at the earth's surface, but penetrates into all holes, crevices, and porous substances, and must therefore be present at considerable depths. Its density at such depths may become very great. not perceive it. For example, the surface of a man's body is about 16 square feet, or 16 x 144 = 2,124 square inches. The intensity of the atmospheric pressure is 14'7 pounds per square inch. The total pressure on the surface of the body is, then, 2,124 x 14'7 = 31,200 pounds, or nearly 16 tons. It might, at first thought, seem that this pressure must crush us. It would do so, were it applied merely upon the outside ; but, through the air and liquids contained in the tissues and passages of the body, this pressure is rendered the same in all directions throughout the interior of the body. The Measurement of Heights by the Barometer depends upon the vertical diminution of the atmospheric pressure. If a barometer be read at the foot of a mountain and then at the summit, the second reading will be less than the first. From the difference in reading, the law of diminution being known, the height can be computed. Owing to the disturbances of pressure accompanying storms, and to irregularities due to temperature and humidity, barometric indications do not afford an exact method of measuring heights. The barometer falls about one inch for the first one thousand feet above sea-level, but this rate is not maintained. Buoyancy of Air. — Fig. 121 shows a hollow sphere suspended from one arm of a balance beneath the receiver of an air-pump. Any light object will answer instead of the sphere. With the receiver removed, adjust the weight on the balance-arm until the sphere is exactly counterpoised. Then put the receiver in place and exhaust the air. The sphere will descend, showing that its weight has apparently increased as compared with that on the other arm of the balance. But no change has been made except the FIG. 121.— GLOBE UNDER removal of the air from the receiver. an amount equal to the weight of water displaced. Objects in air, and in all fluids, are buoyed up in precisely the same way by an amount equal to the weight displaced. Thus, when the sphere was counterpoised in the air, it was buoyed up by the weight of its volume of air. All the other parts of the apparatus were also similarly buoyed up. When the air was removed from around the apparatus, the buoyancy ceased. Every part of the apparatus gained in apparent weight, then, by an amount equal to the weight of the air it had displaced. But the sphere, being larger than the other parts, displaced more air, and therefore was more buoyed up. Hence, when the buoyancy was removed, it appeared to gain more in weight than the other parts, and that side of the balance went down. In weighing any object accurately, the buoyancy of the air must be allowed for. Both the object and the weights are, of course, buoyed up, and appear too light. But generally the weights are of brass, which is more dense than most materials, so that the object loses more in weight than the weights. The weight of a litre of air is only about one gramme, so that the loss of weight of most objects is so small as to be neglected in commercial and in most engineering work. As all ING PRINCIPLE OF BALLOON. ing gag wiR angwer equally well, a glass tube or a clay pipe being connected with the gas-jet by a rubber tube, and its end dipped into the soap mixture of page 174. The hydrogen is so much less dense than air, that the bubble, even including the weight of the film and hydrogen together, is lighter than the air displaced. weight, and, like a block of wood in water, tends to rise. The hydrogen bubble is a miniature Balloon, for a real balloon is merely a bubble whose walls are of a very light, strong material, such as silk made impervious to hydrogen. The balloon is filled or inflated with this " gas," and therefore rises with the car and its load. The large size of an ordinary balloon is requisite in order that the difference in weight between the hydrogen contained and the air displaced shall be at least equal to the weight of its walls, together with that of the car and its contents. The ordinary toy-balloon is a rubber bag inflated with hydrogen or illuminating gas. The gas soon escapes by diffusion through the rubber, allowing the bag to collapse. On account of the buoyancy of air, hydrogen and other gases less dense than air tend to rise through it. Hydrogen, for instance, can be held in a jar placed mouth downward, while it would rise quickly out of a jar placed mouth upward. It can be poured from one jar into another by holding them both mouth downward and then inclining the one containing the gas beneath the mouth of the other, into which the hydrogen will rise, displacing the air. This process is exactly the opposite of pouring water, as it is pouring upward instead of downward ; but gravity is in each case the source of energy. Gases more dense than air can be poured just as water is. Hot air, being less dense than cold air, is buoyed up in cool air by a force greater than its weight, and therefore tends to rise. This gives us the draught in our chimneys as well as many of the currents of the atmosphere. Smoke is mainly composed of particles of carbon which rise only because carried along by hot air. Hot air was also used instead of hydrogen in the earliest forms of balloons, and is the means by which fire-balloons are made to rise. QUESTIONS.— Describe an experiment to show the diffusion of gases through a porous partition. Give an account of the free diffusion of gases. How is it explained on the molecular theory ? Which diffuse faster, the more or the less dense gases ? Why ? Illustrate the osmosis of gases. Of what does the atmosphere consist ? Draw a diagram illustrating the variation of pressure of the atmosphere with the height ? If a barometer were carried up to a point where it read only 15 instead of 30 inches, how much of the mass of the atmosphere would be above it ? About how high would this be ? What phere stratify, as oil and water do, into layers of nitrogen, oxygen, etc. A house is 30 feet long, 40 feet broad, and 30 feet high, with flat roof. How much is the total atmospheric pressure on its outside surface » Why does it not collapse ? Would it collapse if the air were removed from it ? Why do we suppose that air exerts a buoyancy ? How may we prove it ? How is this allowed for in weighing ? Why is it imperceptible in ordinary weighing ? Why do bubbles filled with hydrogen rise ? Why does hot air go up the chimney ? Does it appear to you that gases and liquids closely resemble each other in properties ? More closely than liquids resemble solids ? which they are operated. Is the city or town in which you live supplied with water from some pond or lake ? How far is the water conveyed in pipes ? How high does it rise in the dwelling-houses ? Explain the principle of the garden fountain. Bore a hole in the bottom of a pail of water. What happens ? Bore a hole in the side of the same pail. What takes place ? Bore a hole in the bottom of an empty pail and hold it upright in the water. What occurs ? What do these three results prove ? A box 4 feet deep by 2 feet wide by 3 feet long, with its bottom horizontal, is full of water. What is the intensity of pressure on the bottom ? What is the total pressure on the bottom ? What is the average intensity of pressure on its side ? What the total pressure ? What is the total pressure on the end ? What would be the weight of water contained in the box ? If the box was closed on the top and a square tube 12 feet high and O'l inch on a side projected vertically from it and was full of water, what would be each of these pressures ? What would be the total weight of the water ? How is it possible that the pressure on the bottom of the box can be so much greater in the second than in the first case with so little more water ? Where is the upward pressure exerted in the second case which counterbalances all the downward pressure except that exerted through the lower end of the tube ? What would be the amount of each of these weights and pressures if mercury were used instead of water ? Why can you float better in salt water than in fresh ? In a lake like Great Salt Lake than in the ocean ? Can you think of any way in which you can increase your buoyancy in water ? Why is it dangerous to struggle and raise the arms if you fall into the water and can not swim ? What should be done under such cirQuinstauces ? Why does the body of a drowned person sink, but after a few days, if the water is comparatively shallow, rise to the surface ? When water is breathed into the lungs, the specific gravity of the body is increased and causes it to sink. After remaining under water for a time, light gases are generated within the body, distending it, and thus lessening its specific gravity, so that it floats. Can a lake be so deep that the body of a person drowned in it will not rise ? The centrifugal tendency in the gyratory motion of a tornado is tremendous, and the diminution of atmospheric pressure at the center is such as to create a partial vacuum. Explain then why, when a tornado passes over a building, the structure may burst into fragments. Heat is a Form of Energy possessed by bodies in virtue of an irregular motion of their molecules, as described on page 37. It addresses the sense of touch. Its nature is imperfectly understood. We consciously perceive it when it is communicated from anything hot to our persons, but we can not explain what it is. NOTE.— With the simple apparatus shown above most of the experiments described in the following section on Heat may be performed : No. 1 represents an iron support, with sliding rings ; 2, a glass beaker ; 3, a cylindrical bulb thermometer ; 4, a glass funnel ; 5, a test-tube stand with tubes ; 6, a Bunsen burner, with regulator for the air, intended to be connected with a gas-jet by a length of rubber tubing ; 7, a pulse glass ; 8, a glass retort ; 9, a U-shaped tube ; 10, a condenser ; 11, a glass balloon, with stop-cock, for weighing gases ; 12, a metal tripod ; 13, a glass flask ; 14, a glass air-thermometer ; 15, an aspirator bottle lor siphon ; 16, a standard balance ; 17, a retort receiver ; 18. a spirit-lamp, which must be substituted for the Bunseu burner when illuminating gas is not accessible. A few perforated rubber corks of different sizes should also be procured, a TEMPERATURE. 231 When heat is communicated to a bod}7, the body is not necessarily perceptibly warmed. If heat be communicated to a substance and does not perceptibly warm it (as when a tumbler of hot water is poured into a pitcher of broken ice), such heat is said to have been "rendered Latent " — in reality, it has been changed into other forms of energy, sometimes partly, sometimes wholly, outside the substance in question. Temperature. — When a body feels hot or cold, we may express the fact by saying that its Temperature is higher or lower than that of the hand. We can not always judge correctly of the temperature of a body by our sense of touch. If, for instance, an iron rod and a piece of wood be exposed for several hours in a hot oven, the iron will feel much hotter than the wo'od. The iron may even blister the hand, while the wood can be held without inconvenience. Similarly, in arctic regions, very cold iron will blister, so that the iron-work of vessels is covered with badly conducting material (see page 276) to prevent the cold metal from coming in contact with the hand. Wood and cloth at the same low temperature do not feel cold. This is because the hot iron parts with its heat more readily than the wood or cloth, while the cold iron removes the heat more rapdily from the hand. A similar fact is observed in the case of oil-cloth and carpets at the same temperature. glass stirring rod, some rubber tubing, and a pound of assorted glass tubing, which may be cut with a wet three-cornered file, or softened in the alcohol or Bunsen flame, and drawn into any desired shape. It is advisable always to protect a glass retort from the Bunsen flame by a square of fine wire gauze. The teacher or pupil will be supplied with this outfit, at a moderate price, by any manufacturer of philosophical apparatus. Where economy is necessary, a sufficiently accurate balance may be made with a cross-bar of hard wood and scalepans cut out of tin. A glass bottle divided in halves furnishes at once a beaker B and a funnel F. Prof. Woodhull, in his "Home-Made Apparatus," suggests that a deep incision be filed in the side of the bottle, and a hot poker be drawn from the incision round the bottle in the required direction. A crack will start at the incision, and follow the poker till the bottle is divided. K a piece of yarn saturated with kerosene be EFFECTS OF HEAT. When Heat is applied to a Body, the effect produced varies with the nature of the body. Heat may cause a rise of temperature, or, as we ordinarily say, the body may become warmer. If the body is solid, it may fuse or liquefy when heat is applied ; and liquids may be vaporized by a continued addition of heat. Some bodies, like wood, do not fuse, but decompose into constituent compounds or elements ; others, like paraffine, decompose after fusion, but before vaporization proper sets in. Heating a body also causes a change in its volume. In most cases, bodies expand when heated. Conversely, if heat be removed from bodies, the changes above named generally take place in the reverse order. Vapors condense into liquids, liquids solidify, and the temperature of bodies falls. If heating a body causes it to expand, cooling will cause it to contract, and vice versa. But the decomposition of bodies effected by heat is not capable of being reversed by a simple process of cooling. Rise of Temperature produced by Heat. — If a vessel of iced water be placed upon a stove, the water becomes warmer, and soon begins to boil. During this operation, the heat obtained at the expense of the burning fuel is being continuously added to the vessel of water. The vessel may be removed to a cold room, where it will serve as a source of heat ; for, as it cools, it imparts the heat which it has received to the room. One system of heating buildings is by the cooling of hot water conveyed in pipes. If the vessel be placed in an ice-box, where it is entirely surrounded by ice, it will cool down to the temperature of the ice. During this operation, the hot water parts with heat, which melts a portion of the ice. The vessel of cold water might now be used to cool a hot room, just as the hot vessel was used as a source of heat. This principle is applied to the cooling of railroad cars, etc., in hot countries. EXPANSION OF SOLIDS. During the coldest mornings in winter, a piece of ice lying on the ground may be much colder than another piece which has just formed by solidification. If heat be applied to the former, it will not at once fuse, but will first become warmer ; and this operation, like those previously described, will require time. The ice behaves like lead or iron which have cooled below the temperatures at which they fuse. The difference in these cases is that lead must be made much warmer than ice, and iron still warmer than lead, before fusion will take place. that shown in Fig. 125. Provide yourself with an iron ball or grape-shot, to which a blacksmith will attach a metal hook, so that you can manage it when hot. Then have constructed an iron ring just large enough to let the ball pass through when they have the same temperature. If the ball alone is heated in the flame of a spirit-lamp or Bunsen burner, it will expand to such a degree that it can not pass through the ring. If the ring alone is heated, it will be too large to fit the ball closely, and the ball can be made to rattle against its interior rim. If both are heated or cooled alike, the ball will always fit the rim. On this principle, the blacksmith heats the iron tire before applying it to the wooden wheel. If a bar of metal is heated, it elongates. In a railroad track, the rails are always left with a little space between their ends, in order to allow for expansion. Conversely, when iron cools, it contracts. The tie-rods of bridges expand and contract under the influence of extreme heat and cold, sometimes to such an extent as to endanger the structures. Expansion of Liquids and Gases. — To illustrate the expansion of liquids, secure a large glass bulb with a capillary stem (see Fig. 126). Insert the open end of the stem in water, and warm the bulb by the hand or with hot water. The air will expand, and part of it will be expelled. As the bulb cools, the air within will contract, and some water will enter through the capillary stem. The bulb may then be placed in an upright position, and the water 'within boiled, care being taken to keep the whole interior of the bulb wet, in order to prevent breakage. If the bulb be again inverted and the end of the stem plunged under water, the bulb will gradually fill as it cools. Why ? In filling a bulb with alcohol or ether, the source of heat should be hot water, and not a flame, in order to avoid explosions. By repetitions of the operation just described, the bulb and a portion of the stem are filled with liquid (see Fig. 126). If the bulb be now placed in hot water, or in melting snow or ice, the expansion or contraction of the liquid within will be indicated by its rise or fall in the tube. The amount of this rise or fall will be greater, as the volume of the bulb is greater, or the bore of the tube is less. Doubling the volume of the bulb will make the rise twice as great, although a longer time will be required to heat the bulb throughout. Reducing the bore of the tube one half will also make the rise twice as great, without increasing the time required by the bulb to respond to a change in temperature. THE THERMOMETER. 235 of mercury as an index, the bulb being filled with air. The heat of the hand is sufficient to send the index through the entire length of the tube, which should be in a horizontal position. Such bulb-tubes are called Thermoscopes. QUESTIONS.— What is Heat ? Outline the accepted theory. When heat has been communicated to a body and does not perceptibly warm it, what has taken place ? Illustrate your answer. What is such heat sometimes called ? Which of the senses does heat address ? How does heat affect the weight of bodies ? What is the Temperature of a body ? Can we judge of a body's temperature by the sensation it produces when we touch it ? Advance facts to prove your answer. What phenomena are observed in arctic regions ? State the several effects of heat ; of cold. Explain the principle on which the heat of burning fuel causes a rise of temperature in water ; the principle on which heat applied to ice may not at once melt it. Show that metals fuse in accordance with the same law. Can you suggest an experiment by which the expansion of solids by heat may be illustrated ? Experiments showing the expansion of liquids and gases ? What is indicated by the Thermoscope ? SCALES. The Thermometer, as usually constructed, consists of a spherical or cylindrical glass bulb, provided with a stem having a fine capillary tube. The bulb and a part of the stem are filled with some liquid, which is then boiled to expel all the air, and the tube is sealed up. Thermometers intended to be used at very low temperatures are usually filled with alcohol, while those designed for ordinary or higher temperatures contain mercury. The air thermometer, already described, is still used. It was employed to measure differences in temperature as early as the sixteenth century, Galileo's first thermometer being constructed on this principle. bulb in melting ice, and in steam from water boiling under the average pressure of the air at sea-level. The temperatures of ice and steam under these conditions are found to be constant. The temperature of melting ice is marked 32° on the Fahrenheit scale and 0° on the Centigrade and Reaumur scales. The temperature of boiling water at the sea-level is marked 212° on the Fahrenheit scale, 100° on the Centigrade, and 80° on the Reaumur. The interval between the freezing and boiling temperature of water is therefore 100 Centigrade, 180 Fahrenheit, and 80 Reaumur degrees. One Centigrade degree is thus equal to £ Fahrenheit degrees. If a Fahrenheit thermometer reads 60°, the temperature is therefore 60 — 32 = 28 Fahrenheit degrees above the freezing-point. But 28° F = f 28° C, or 15°'5 C ; hence if C be the reading of a Centigrade thermometer and F that of a Fahrenheit at the same temperature, FIG. 128.-SCALES COM- That ^ tQ reduce ft Fahrenheit to a Centigrade temperature, subtract 32 and multiply the remainder by f. To reduce a Centigrade to a Fahrenheit temperature, multiply by £ and add 32. Thermometers used in physical experiments are usually provided with a cylindrical bulb, as shown in Fig. 127. In this form, they are both more sensitive and more convenient. Maximum and Minimum Thermometers. — Other forms of thermometers are the maximum and minimum thermometers. As constructed 'for meteorological purposes they are shown in Fig. 129. The maximum thermometer is like an ordinary mercury thermometer, except that the capillary tube has a narrow place near the bulb, through which the mercury is forced as the temperature rises. When the temperature falls, the mercury in the tube remains in position, showing the highest temperature reached. mometer. The minimum thermometer usually has alcohol as a liquid. The tube is of rather large bore; within it is a small glass rod below the surface of the alcohol. When the temperature falls and the surface sinks, the glass rod is forced along by the liquid and does not break through the film which bounds the surface of the alcohol. When the temperature rises again, the alcohol flows past the index, leaving it marking the lowest temperature reached. The maximum thermometer records the highest temperature of the day; the minimum, the coldest temperature of the night. The mean of these temperatures is almost exactly the average temperature of the entire day. When in use, these thermometers are placed in a horizontal position. The Coefficient of Linear Expansion With the aid of the thermometer, the law of expansion of bodies can be examined. If a bar of iron be compared at different temperatures with a standard bar at a fixed temperature, it is found that the elongation of the bar per foot, per degree of temperature, is very nearly uniform at all ordinary temperatures. If this quantity be called a, the elongation of I feet for one degree would be I times as great, or la. If the elongation for / feet heated through one degree is la, for t° A tempered steel bar one foot long, when heated one degree centigrade, will become 1-0000124 feet in length. If one mile long, it would become 1-0000124 miles, the increase in length in the latter case being 0-0654 feet. When heated from 0° C. to 20° C., the mile bar would be increased in length 1-3089 feet. As the Fahrenheit degree is only f as long as the Centigrade, the coefficients of expansion for the Fahrenheit degree would be % of those given above. coefficients of expansion of different substances being known, it is easy to arrange a system of rods which shall be compensated for changes in temperature. Let S B (Fig. 130) be a glass rod 40 inches in length suspended at S and having a washer B cemented to its lower extremity. B N is a perforated cylinder of zinc slipped on over the rod and resting upon the washer. What must be the length B N of the zinc cylinder in order that its upper end shall always remain at a fixed distance from S when both rod and cylinder are equally heated lows : The elongation of the glass rod downward, when heated any number of degrees t, will be 0-0000086 x 40 x t inches. The zinc cylinder having a length I, when heated an equal number of degrees, will elongate upward 00000294 x I x t remain constant for varying temperatures. The expansion thus far treated is the expansion of the linear dimensions of bodies, and the coefficients given in the table are called coefficients of linear expansion. It now becomes possible to determine the effect of expansion upon the volume of a body. This increase in volume is called Cubical Expansion. — A cube of cast iron whose edges are one foot in length, when heated 1° C., would become slightly larger. The length of each edge would be increased by 0-00001125 feet. The cube would then be one having edges 1-00001125 feet in length. The expanded cube might be conceived to be made up from the smaller one by placing three thin blocks upon three of the faces, as is shown in Fig. 131, where the thickness of the blocks is magnified 10,000 times. The thickness of each block being 0-00001125 feet, and the other edges being one foot in length, the volume of each slice 1 x 1 x 0-00001125 = 0-00001125 cubic feet. The volume of the three slices is then 0-00003375 cubic feet. In order to complete the cube, we need three slender rectangular blocks laid along the edges shown in the figure, and a little cubical block in the corner. The three blocks will each have a volume of 0-00001125 x 0-00001125 x 1, or 0-000000000126 cubic feet, so that the three will have a volume of 0 000000000378 cubic feet. The volume of the little cube required to fill out the corner will be 0-00001125x0-00001125x0-00001125, or 0-00000000000000142. Adding these three quantities, the volume of the expanded block will be — 240 HEAT. It is evident that the two volumes last written are too small to merit any consideration in comparison with the preceding one, which is itself insignificant when compared with the original volume. The cubic foot of cast iron may, then, be said to increase to 100003375 cubic feet when heated through one degree C. Coefficient of Cubical Expansion. — The increase in volume of the unit volume, when heated through one degree, is called the coefficient of cubical expansion. The coefficients of cubical expansion of the substances named in the preceding table may therefore be obtained by multiplying their coefficients of linear expansion by three. The coefficient of cubical expansion of white glass is 0-0000258; that of mercury is 0-000181. Hence, if a vessel holding 1 cubic inch is full of mercury at a temperature of 0° C., and is heated 1° C., the mercury will expand more than the glass by 0-000181 — 0-000026 = 0-000155 cubic inch. If glass expanded more than mercury, the column in a thermometer would fall when the temperature rises. If a thermometer at any ordinary temperature be plunged into warm water, the column will at first sink and then rapidly rise. This is due to the fact that the glass bulb is heated and expands before the mercury is appreciably affected. If the thermometer be plunged into icewater, the converse effect will take place. The experiment may be made more striking by means of the apparatus shown in Fig. 132. This consists of a common two-quart bottle, filled with cool water, and closed by a stopper through which passes a glass tube. Just above the cork, the tube is drawn out fine. The upper surface of the water should be half-way up the narrow part of the tube. If the end of the FIG. ^-BOTTLE AND finger be now Placed against the side of the GLASS TUBE. bottle, the liquid in the tube rapidly falls, show- ing that the glass expanded and bulged out where the warm finger was applied. The experiments previously described with the thermometer can readily be made with this apparatus. QUESTIONS.— What instrument is used for measuring changes of temperature ? Describe the Thermometer and its construction. How is the scale of the thermometer established ? Name the three principal scales. What are the freezing and the boiling points respectively called in the Fahrenheit scale ? What, in the Centigrade ? What, in the Reaumur ? How may a Fahrenheit tempera ture be reduced to its equivalent in centigrade degrees ? A centigrade temperature to its Fahrenheit equivalent ? Describe the maximum and the minimum thermometer. How is the mean temperature of the day determined ? In what way may the law of expansion be studied ? What is the coefficient of linear expansion ? Explain temperature compensation, and the practical use that is made of coefficients of expansion in the construction of the pendulum. Define cubical expansion, and show how the coefficients of cubical expansion are obtained. Illustrate in the case of a cube of iron to which heat is applied. In the, ordinary thermometer, which expands first, the glass or the mercury ? Which expands more ? Fully illustrate the principle. Why does heating the neck of the bottle uniformly in an alcohol flame loosen a tight glass stopper bottle of iced water shown in Fig. 132. If the apparatus is placed in a warm room, and allowed to heat slowly, the column of liquid will descend at first and afterward rise. The apparatus of Fig. 133 has been used to determine the temperature at which water is most dense. It consists of two tubes of galvanized iron, about four inches in diameter and five feet high. At the bottom, the tubes are connected by a pipe provided with a cock, by means of which they may be put in communication. At the top, they connect through an open trough. If the left-hand tube be filled with water at 0° C., and the other with water at 8° C., so that the water stands about a quarter of an inch deep in the trough, and the tubes are then put in communication at the bottom, there will be no current in the trough. If the water in the left-hand tube be maintained at 0° C. by means of melting ice, and that in the other be allowed to warm a little, a gentle current will flow through the trough from right to left. This shows that the water must flow through the lower pipe in the opposite direction, and that the water at 0° C. exerts a greater pressure than that of the warmer column. By cooling the warmer water below 8° C. the currents are reversed. In this way, water at 7° C. is found to have the same density as at 1°, at 6° as at 2°, and at 5° as at 3°. Phenomena of Freezing. — This property of water plays an important part in the preservation of the lives of animals inhabiting lakes and ponds. Only extremely shallow bodies of water are ever frozen to the bottom. After the temperature of a pond has been lowered to 4° C. (39-2° Fahr.) by the alternate sinking of heavier portions of water cooled at the surface, and rising of warmer and lighter particles from below, the surface layer, as it grows colder, begins slowly to expand. Hence it floats ; and finally, when it is cooled to 0° C. (32° Fahr.), it crystallizes into ice, while the water below remains at 4° C. On freezing, the ice expands still more, the density of water at 0° C. being 6241 pounds to the cubic foot, while that of ice at the same temperature is 58-05 pounds. Ice, therefore, always floats, and thus protects the denser water beneath, and the fishes and plants that inhabit it, from further reduction of temperature. The pressure exerted by freezing water is irresistible. It often causes damage by the bursting of lead and iron pipes, and injures buildings and stone-work. The farmer avails himself of the expansion of water in freezing to break up the pieces of the soil which he plows into furrows in the autumn, and is often under the necessity of resetting, in the spring, fence-posts which have been loosened by the frost. Water freezing in the crevices of rocks splits them into fragments, as evidenced by the broken stones lying at the base of cliffs. In this way, the obelisk in Central Park, New York, is being defaced. Expansion of Gases. — The apparatus shown in Fig. 132 serves to illustrate the expansion of gases. If it be filled with air, and the end of the tube be placed under water, the air will bubble out when the bottle is heated. and break the bottles. Fill a small tank with iced water. Keep the bulb of the airthermometer in the water until it has cooled down to zero, and then immerse the whole tube, and fasten it in a horizontal position, as shown in Fig. 134. The bulb and tube are now full of air. Dip out cold water, and replace it with warm. Air will escape on account of expansion, and may be collected in a graduated tube. After having heated the air to any desired temperature, say 50° C., maintain this temperature until air ceases to escape, and then cool the water again to zero. Water will enter the bulb to replace the expelled air. Lower the mouth of the collecting tube to the bottom of the tank, so as not to lose the gas, and take the bulb-tube out of the water, dry and weigh it. If the water in the stem runs out as the warm air strikes the bulb, it must be collected and weighed with the bulb. The excess of this weight over that of the bulb alone gives the number of grammes, or cubic centimetres, of water in the bulb, or the number of cubic centimetres of air expelled. The expelled air, if cooled down to zero, should give the same result, by direct measurement. The capacity of the bulb can now be found by filling the bulb and stem with water at zero C., and again weighing. If the empty bulb weighed 5'2 grammes, and when full weighed 120'5 grammes, then it holds 115'3 grammes of water, and the air originally in the bulb was 1153 cubic centimetres. The expansion of the glass is so small in comparison with that of the gas that it may be neglected. From these data, how would you find the increase in volume of 1 cubic centimetre of air, when heated 1° C. ? This quantity is called the coefficient of expansion of air. The Coefficients of Expansion of all Gases are nearly the same, under all pressures and at all temperatures. The value of the coefficient is ^ = 0-00366. A cubic foot of gas at 0° C., when heated 1°, will become 1 -f 0-00366 cubic feet. When heated to tf°, it becomes 1 _j_ 0-00366 £ cubic feet. If t is 100°, the mass of gas which would have 1 cubic foot of volume at 0°, would become 1-366. In like manner, 1 cubic inch at 0° would expand to 1-366 cubic inches at 100° 0. If the Fahrenheit degree is used, the coefficient of expansion becomes $ x Y?"3 = T5iT' A quantity of gas heated from 0° to 273° C. would double in volume, if the pressure remained unchanged. THERMAL UNITS AND SPECIFIC HEAT. Quantity of Heat. — A Bunsen burner placed under a flask containing a quart of water, will soon raise the temperature of the water to the boiling-point. If we were to attempt to boil a thousand quarts of water in a vessel, by means of the same burner, but slight effect would be produced. It would require a thousand burners to bring about rapidly the same result. In this latter case, the amount of gas burned would be a thousand times as great, as would, also be the amount of heat required. THE HEAT UNIT. 245 Unit Quantity of Heat. — The unit quantity of heat is the heat required to raise the temperature of a unit mass of water through 1°. The actual magnitude of the heat unit depends upon whether the unit of mass be the pound, ounce, gramme, or kilogramme, and whether the thermometer be the Centigrade or Fahrenheit. To heat a thousand pounds of water 1° will require a thousand heat units ; to heat it 5°, five thousand. If a Bunsen flame be applied to a flask containing 500 grammes of water, which it heats through 5° C. in one minute, the heat added to the water is 2,500 heat units a minute. If 960 grammes of water at 2° C. be mixed with 800 grammes at 24 C., there will result 1,760 grammes of water at a temperature t. This temperature will evidently lie between 2° and 24°, and must be of such value that 8QO grammes cooled from 24° to t° will give up enough heat to heat 960 grammes from 2° to t°. The heat lost by the hot water is therefore 800 (24— £)• The heat gained by the cold water is 960 (t—2). These values must be equal ; or 800 (24—0 = 960 (t—2). Hence t = 12. If equal quantities of hot and cold water be mixed, the resulting temperature will be the mean of the hot and cold temperatures. If the hot water be twice the amount of the cold, its change in temperature in reaching the temperature of the mixture will be half that of the cold water. PROBLEM.— Suppose x grammes of water at a temperature of 75° to be mixed with 40 grammes of water at 3°. The temperature of the mixture is 15°. Find the value of x. The x grammes in cooling from 75° to 15° loses (75 — 15) x = 60 x heat units. The 40 grammes in heating from 3° to 15° requires 40 (15 — 3) = 480 heat units. Hence 60 x = 480, and x = 8. Specific Heat. — The ratio obtained by dividing the amount of heat required to warm a given mass of any substance one degree by the amount required to heat an equal mass of water one degree, is called the Specific Heat of that the specific heat of water being reckoned as 1. It is therefore evident that the specific heat is numerically equal to the quantity of heat required to raise the temperature of a unit mass of a given substance one degree. It must be understood, however, that specific heat is a ratio of two like values. As in the case of specific gravity, it is represented by an abstract number. The Calorim'eter is an instrument for measuring quantities of heat. It is made in different forms, according to the uses for which it is intended. The fact that water has a high specific heat measurably determines the equable character of an oceanic climate. The water of the ocean may part with a large amount of heat in winter without getting cold, and may in summer receive a large amount without becoming warm, differing thus in a marked degree from dry soil. The effect of the sun in producing a high temperature is five times as great on dry sand as on water. QUESTIONS.— State the general law of expansion. What exception is there to the law that liquids are expanded by heat and contracted by cold ? Mention the temperature at which water is most dense. How is this determined ? Explain what occurs when a pond freezes over. Show what part this provision of Nature plays in the preservation of fish-life. What examples can you cite to prove the great force with which water expands when freezing ? Can you mention some familiar illustrations from your own experience ? Name three temperatures that are important for you to remember in connection with water, and explain the significance of each. Illustrate the expansion of air by heat. What is the coefficient of expansion of a gas ? How do the coefficients of expansion of gases differ ? Define a heat unit. On what does its magnitude depend ? How do we estimate the temperature of a mixture of two quantities of water differing in temperature and weight ? Of two quantities of lead and water ? Of equal quantities of hot and cold water ? Explain Specific Heat. Describe the calorimeter. In determining the specific heat of different substances, what is assumed as a standard ? Compare the standard with the specific heat of other bodies. Explain the relative influence of land-masses and water in modifying climate. FUSION AND VAPORIZATION. Fusion illustrated. — Place a metallic vessel containing a pound of water over a Bunsen flame. If a thermometer inserted in the water shows a rise in temperature of 2° C. a minute, then the flame is imparting to the water two heat units a minute. be placed in the vessel, the flame remaining as before, the temperature will continue at 0° C. until all the ice is fused. If a flame capable of imparting two heat units a minute to water at 0° C. be used, in a room where the temperature is 0° C., it will take forty minutes to melt the ice, showing that it requires eighty heat units to fuse one pound of ice. To fuse a pound of ice requires as much heat as would raise the temperature of 80 pounds of water 1°, or 2 pounds 40°. If one pound of ice at 0° be placed in 10 pounds of water at 8°, the water will cool to 0°, and in so doing will yield heat just sufficient to fuse the ice. The heat required to fuse the ice is 5 x 80. The resulting ice-cold water is heated from 0° to <°, requiring 5 t heat units. The total heat applied is therefore 5 x 80 + 5 1 . This heat is obtained from the hot water, which cools down from 90° to t, yielding 100 (90 — t) heat units. Hence 5 x 80 + 5 t = 100 (90 — t ), or 105 t = 8600, or f = 81'9. When a solid is converted into a liquid, heat is absorbed. This is the principle on which freezing mixtures operate. Ice-cream, for instance, is frozen with a mixture of salt and snow or pounded ice ; the latter is rapidly melted, and so much heat is absorbed in the process that the cream is brought to a solid form. Differences in Fusibility. — Bodies differ widely in fusibility. Alcohol has never been rendered solid, its fusing-point being below the lowest attainable temperature. Mercury fuses at — 38-8 C. ; ice, at 0° C. ; lead, at 335° ; and iron at about 1,500°. Substances like paper, wood, and cloth, do not fuse at high temperatures, but are decomposed ; while carbon has neither been fused nor decomposed. Bodies like carbon are said to be refractory. The number of refractory bodies has steadily diminished as methods of producing higher temperatures have been invented. Even carbon has been softened. Alloys. — When fused metals are mixed, they frequently form a homogeneous metal, known as an Alloy, having different properties from any of its constituents. Alloys usually fuse at lower temperatures than any of the metals composing them. 4. During fusion, the temperature remains constant. Increasing the temperature of the source of heat causes the body to fuse more rapidly, but does not raise its temperature. 5. To fuse a gramme of any substance under constant pressure requires a definite quantity of heat, which is different in the case of each fusible substance. Vaporization. — If a vessel containing 1 pound of water be heated by a lamp capable of raising its temperature from 90° to 100° C. in five minutes, then two heat units will be added to the water each minute. When 100° is reached, the 'temperature will cease to rise, although two heat units a minute are still being added to the water. The heat is now being used in the vaporization of the liquid. It will require 268'5 minutes to evaporate (convert into a gaseous state) the pound of water with such a flame. Hence the heat required to evaporate the water is 537 units. When a gramme of steam condenses to water without any change of temperature, the heat required to raise the temperature of 537 grammes of water 1° C. is evolved. Such is the source of heat in the steam coils used in warming buildings. Phenomena of Evaporation. — Some substances, like musk, camphor, and ammonium carbonate, vaporize without going through a process of fusion. Moreover, a high temperature is not essential to vaporization. At ordinary temperatures, wherever a surface of water is in contact with the air, vapor is formed, and by this means the atmosphere becomes charged with moisture. Whenever vapor is formed, heat is absorbed, and cold is produced. Hence, when the skin is moistened with a volatile liquid like ether or cologne water, a sensation of cold is experienced. Fanning-cools the face by rapidly vaporizing the insensible perspiration which Nature has provided to regulate the temperature of the body. The cooling which accompanies the evaporation of sweat is one means of preventing the bodily temperature from rising above the natural standard of 98'5°. A high external temperature can, therefore, be borne as long as the skin responds with an increased secretion of perspiration. Sculptors have worked with safety in dry ovens at a temperature of more than 100° Fahr. above the boiling-point of water. A drop of water let fall on a cold iron moistens its surface ; if let fall on a very hot iron, it hisses and runs off without leaving any trace of moisture. In the latter case, the water does not touch the iron at all, but is separated from it by a layer of steam. Laundresses try their irons with wet fingers, to see if they are hot enough for use. On the same principle, jugglers plunge their hands into melted metal with impunity, by first wetting them. The drops of moisture on their hands assume a spheroidal form, and in this state evaporate much more slowly than at a lower temperature, keeping the molten metal from contact with the skin. This condition, which is assumed by liquids when exposed to the action of very hot metals, is known as the SPHEROIDAL STATE. Phenomena of Boiling1. — When a glass flask partly filled with water is heated, bubbles of air become visible on its sides. They appear at a low temperature, and may even be seen in a vessel of water standing in sunlight. Finally, as the temperature nears the boiling-point, bubbles of steam begin to form at the bottom of the flask, rise, and collapse with a sharp, snapping sound. The upper portions of the liquid being somewhat cooler than those below, fusing-points of substances vary, so do the temperatures at which they boil. Liquids which boil at low temperatures are said to be volatile. If a test - tube containing ether be dipped into a beaker of water having a temperature of 50° or 60° C., the ether will begin to boil, and a thermometer placed in the ether will indicate a temperature of 35° C. If the water is warmer, the ether will boil more briskly, but its temperature will remain unchanged. The heat required to vaporize the ether will be taken from the water, which will therefore cool more quickly than it would if the ether were not evaporating. Distillation. — If any liquid is required to be separated from a salt which it holds in solution in such a manner as to save the liquid, the solution must be heated in a retort or boiler known as a " still," shown in Fig. 137. The vapor passes into a tube or worm (d d), surrounded by cool water or ice, and is thus condensed and collected in a vessel called a " receiver " (g). The salt remains behind in the retort. This process is called Distillation, and it is possible because some substances are converted into vapor at lower temperatures than others. Alcohol and other volatile liquids can be separated from water by the same apparatus. The temperature of the retort is raised to or slightly above the boiling-point of the more volatile liquid, which then passes off as vapor, leaving the less volatile liquid behind in the retort. A little of the latter is indeed carried over, particularly toward the last, so that the first part of the distillate is sometimes collected in a separate vessel. Further purification can be effected by repeated distillation. The pupil may readily improvise a simple still with a glass retort, retort-receiver, and common tin basin filled with cold water. If provided with a condenser (Fig. 10, page 230) he should arrange it, by the aid of corks and glass or rubber tubing, between the receiver and the retort. If water during the prevalence of epidemics. Distill a small quantity of salt or sea water. The water in the receiver will have a disagreeable, flat taste, because it is not aerated, or does not contain air, as all drinkable water should. Shake it repeatedly in a large clean bottle and it will lose its unpleasant taste. Introduce some fragrant roses into the retort with water and apply heat. The essential oil of the flowers, known as attar, will pass over with the steam, imparting a perceptible perfume to the water that condenses in the receiver. Large quantities of flowers are distilled in this way; the oils float and are removed. Dissolved in cologne spirit, they constitute perfumery extracts. QUESTIONS.— What do you understand by fusion ? Illustrate your answer. How much heat is required to fuse a pound of ice ? How many thermal units ? On what principle do freezing mixtures operate ? Do all bodies fuse at the same temperature ? Illustrate the difference, as regards their capability of being melted, in wax, mercury, alcohol, lead, gold. What is meant by a refractory body, and what is probable of all refractory bodies ? Define an alloy. Formulate a general rule for the fusing-points of alloys. Sum up the laws of fusion. What is vaporization ? Mention the successive effects of heat on solids. May » body vaporize without fusing ? Is heat essential to vaporization ? Prove that cold is produced when vapor is formed. Why is this ? Why does fanning cool the face ? Can you explain the office of perspiration. Describe the spheroidal state, and explain what practical advantage may be taken of the tendency of liquids to assume this condition. What is the temperature of water in the spheroidal state ? Only about 95° C. Describe the phenomena of boiling. Explain the singing of the tea-kettle. Does the temperature of a liquid alter during boiling ? Do all liquids vaporize at the same temperature ? Contrast ether with water in this respect. \V hat is distillation, and on what fact is the process based ? What is an apparatus for distilling called ? Describe the still. Explain how a simple still may be improvised. How may pure water be obtained by the use of this still ? How, the essential oils of flowers ? Why is not distilled water palatable ? BOILING POINTS. Boiling- and Fusing Points vary according to the pressure. When a substance expands in solidifying, as in the case of water and some of the metals, the operation is resisted by atmospheric pressure. If water at 0° could be prevented from expanding by inclosing it in a vessel of sufficient strength, it would not freeze if cooled far below the freezing-point. If ice at 0° is put under a pressure of 20 atmospheres, it will fuse. In fusing, it diminishes in volume, and the increased pressure aids the operation. Water under such pressure would not freeze until it had cooled 0-15° below 0° C. If the pressure on the ice be less than one atmosphere, it will not fuse at 0° but at a slightly higher temperature, because the aid which the operation derives from atmospheric pressure is diminished. In the case of substances which contract in solidifying, all these statements would be reversed. Iron and type-metal expand when they solidify, and therefore fill molds and make sharp castings. The reverse is true of silver and gold. Coins made of these metals are therefore stamped with a die. Water expands greatly on vaporizing. A cubic inch of water will make about a cubic foot of steam at one atmosphere pressure. The formation of steam is resisted by pressure ; hence if the pressure be more than one atmosphere, the water must be made hotter than 100° before it will boil. Conversely, if the pressure on the water is diminished, the water will boil at a lower temperature than 100° C. On Pike's Peak, at an altitude of 14,000 feet, where the barometer column may be only 18 inches high, the temperature of boiling water is only 188° Fahr., or 86-6° C. At such places food which is cooked by boiling water requires a much longer time for its preparation than at the sea-level. cold water standing at some distance below the flask. The water in the flask is heated to boiling, and its temperature is noted by the thermometer when it discharges into the open air, and also when the lower end of the tube is immersed in the iced water. In the latter case, the water in the flask will be seen to boil at a temperature below 100°, and the iced water may rise in the tube. This rise of the water may be increased by clamping ice-blocks around the tube and moving them up and down so as to cool the whole tube, or by surrounding the tube with ice in a vessel, as in the figure. The pressure within the flask is less than the atmospheric pressure by the pressure due to the column of water in the tube. If the flame be removed, the lower end of the tube closed by the finger, and the flask then wrapped with a cold wet cloth, the water in the flask will begin to boil vigorously. This is due to the condensation of the steam in the upper part of the flask, which reduces the internal pressure and The same phenomenon may be shown with a pulse-glass containing colored ether (Fig. 140). One bulb is surrounded with ice or snow, and the other is then placed in hot water. The hot water causes the ether to boil, and the vapors are condensed in the second bulb. Boiling under High Pressure. — In an ordinary steamboiler, if the steam is not drawn off or condensed, evaporation apparently soon ceases. The steam space is then said to be saturated. Particles of water are indeed still flying off from the surface of the water into the steam space above, but this space is so full of particles that an equal number are continually plunging down upon the water surface and becoming part of the liquid. If the fire is now made hotter, the molecular agitation of the water is increased, so that particles are shaken loose from the water surface in greater numbers than they are returned ; but this crowds the steam space more densely, and very soon equilibrium is again reached. The steam space is saturated at a higher temperature and pressure. If steam is drawn off to feed an engine or to heat rooms, then evaporation will go on continuously, the boiling-point depending upon the resulting boiler pressure. With increasing pressure, there is no limit to the rise in the boiling-point except the strength of the boiler. The temperature of boiling water under pressures ranging from one to ten atmospheres is given in the following table : The following table, which forms the basis for observations on atmospheric humidity, gives the vapor pressure in inches of mercury in a boiler corresponding to various temperatures, from 0° Fahr. to 101° Fahr. Thus, at 32° Fahr., where the boiler is surrounded by ice-water, the vapor pressure within would be 0-181 inch of mercury. The apparatus by means of which the values of the last table were obtained is shown in Fig. 141. A copper vessel, C, serves as the boiler. This is partly filled with water, into which four thermometers dip to various depths. The thermometers fit into air-tight packing in the cover, and the mercury can be read above. By means of a tube, A B, the steam space in the boiler connects with a glass globe contained in DIFFERENT TEMPERATURES. the vessel, M, having a capacity of about six gallons and filled with air. To the upper part of the globe is attached a tube with two branches. One of these connects with an instrument which measures the pressure within the globe, tube, and boiler. The other communicates at H with a compressing or exhausting air-pump, by means of which the pressure can be varied at will. The globe in M is kept cool by surrounding it with water, and cool water is passed through the jacket which encompasses the tube A B. When the water in C is boiled, the steam condenses in the pipe and globe and runs back into the boiler. Whenever the pressure is fixed, whether produced by the generation of steam or by the forcing of air into the globe, the temperature is always the same. For in- stance, whenever the pressure inside is reduced to Q'22 inch of mercury, the water boils at 37° Fahr. and can not be heated above that temperature if the pressure is held constant. Making the flame under the boiler hotter will cause the water to evaporate more rapidly, but will not raise its temperature. the connection with the air-pump be opened so that the steam will drive all the air from the apparatus, and if the pipes be then closed and the vessel and boiler be put into ice-water, the steam will nearly all condense. There will, however, still be a pressure of 0-181 inches of mercury in the boiler. If the boiler be cooled to — 30° Fahr., the pressure will diminish to 0-009 inch of mercury. Even at such low temperatures, ice slowly evaporates. In this way wet clothes become dry in freezing weather, and snow and ice slowly disappear, although the temperature may be continuously below the freezing-point. Probably if ice were cooled to — 75° C. it would not appreciably evaporate, but would behave as lead or zinc at ordinary temperatures. At higher temperatures, these substances themselves may be vaporized. QUESTIONS.— State fully the influence of pressure on fusing and boiling points. How may water be prevented from freezing at a temperature below 0* C. ? Why can iron be molded better than either silver or gold ? To how great a degree does water expand on vaporizing ? Under what circumstances will water not boil at 100° C. ? When will it boil at a lower temperature ? Will it then cook food ? The Dead Sea is 1,272 feet below sea-level. At what temperature does water boil on its shore ? At about 214* Fahr. Illustrate the boiling of water at a reduced temperature and pressure. The boiling of ether. In Fig. 140, page 256, if the cold bulb is removed from the ice while the other remains in the hot water, the apparatus will quickly explode. Why ? Describe the phenomena of boiling under high pressure in an ordinary steam-boiler. How will the temperature vary ? Under a pressure of ten atmospheres, what is the boiling-point of water ? Name the only limit to the rise in the boiling-point. State the pressure in locomotive-boilers. Explain the apparatus by which the steam pressures corresponding to different temperatures are ascertained. Why is the temperature always the same when the pressure is constant ? What effect is apparent on increasing the heat applied to the boiler ? What can you say of the vapor pressure below the freezing-point ? Does ice evaporate at low temperatures ? Is there any conceivable temperature at which snow and ice would not slowly disappear ? but is rarely if ever saturated, so that no further evaporation can take place from bodies in contact with it. Steam from a tea-kettle is invisible for about an inch from the spout. It eventually condenses into a cloud of minute water-globules, which evaporate quickly In a saturated atmosphere, the cloud would not evaporate. Atmospheric Humidity. — The weight of moisture in a unit volume of the air (in grains to the cubic foot, or in milligrammes to the cubic metre) is called its Humidity. It may be measured by means of the apparatus shown in Fig. 142. water is provided with a siphon, through which the liquid may be drawn off. The air space in the bottle is connected, as shown, with two U-tubes containing fragments of chloride of calcium, or pumice-stone impregnated with sulphuric acid. When the water runs out of the bottle, air enters to supply its place through the U-tubes. The first tube, A, absorbs all the moisture from the air, while the second tube, B, intercepts any moisture which may proceed from the bottle. Measure the volume of the water that has run out. This is equal to the volume of air which has passed through the apparatus. Tubes A and B are weighed before and after the experiment. The increase in weight gives the moisture in the measured volume of air, from which the moisture in grains to the cubic foot can be found. The humidity in grains to the cubic foot for saturated air is given in the accompanying table for various temperatures: Dew-Point. — If a tin cup containing water is cooled gradually by adding small pieces of ice and stirring the water, moisture will finally condense on the outside of the cup in the form of -dew. Drops of water are frequently a small fragment of ice, when the dew is first observable, remove the ice at once and observe the temperature of the water. Allow the water to stand until the dew disappears, and again observe the temperature, keeping the water stirred. The mean of these two temperatures is the dew- point. If the air were to be, cooled to this temperature, it would be saturated with moisture, and any further cooling would precipitate the moisture as a cloud. The most suitable apparatus for determining the dew-point is Regnault's (reh-no1) hygrometer, shown in Fig. 143. It consists of two glass tubes, one of which (D) connects by means of a T-tube with an aspirator A. Both tubes contain thermometers fitted into their stoppers. The tube connecting with the aspirator has also an air-tube passing nearly to the bottom, and is in part filled with ether. When water puns from the aspirator, air is drawn through the ether, which vaporizes, cooling the remaining ether and the tube. When dew is observable on the silver thimble which caps the lower end of the tube, the water is checked and the thermometers are both read. The ether is now allowed to warm up until the dew disappears, and the thermometers are again read. The mean of the two readings of the cooled thermometer is the dew-point. The other thermometer registers at the same time the air temperature. A simple apparatus, which will give very good results, may be made from an ordinary test-tube partly filled with ether, containing a thermometer, and a glass tube connected with a rubber coil two or three feet in length (see Fig. 144). Air is blown through the tube, vaporizing a portion of the ether and thus producing cold. Follow the same directions as in the case of Regnault's hygrometer, and determine the dew-point. The air temperature may be ascertained from an ordinary thermometer. Relative Humidity. — Suppose the air temperature to be 70° F. and the dew-point 58° F. If the air were cooled down to 58°, it would be saturated with moisture. From the table of pressures of vapor (page 257) it will be seen that saturated vapor at a temperature of 58° has a pressure of 0'482 inch of mercury. This much of the atmospheric pressure shown by the barometer is due to moisture. RELATIVE HUMIDITY. 263 If the air were saturated with moisture at 70°, its vapor pressure would be 0-733 inch of mercury. The amount of moisture to the cubic foot would then be greater than it is at 58° in the ratio 0-733 -f- 0-482. The amount of moisture actually in each cubic foot of air would be a certain fraction of what that cubic foot would contain if saturated. That fraction is 0-482 + 0-733 = 0-65. The relative humidity is the ratio of the amount of moisture in the air to the amount required to produce saturation. In the case instanced above, the relative humidity is 65 per cent. At 70°, the air could hold 4-53 grains per cubic foot. Hence, at 58°, it would hold 65 per cent of 4-53, or 2-94 grains. When the Relative Humidity is low — that is, when the air is dry — we feel little inconvenience, even if it is very warm. Perspiration rapidly evaporates, and its latent heat is thus taken from the body, keeping it cool. If the air were saturated, its relative humidity would be 1-00, or one hundred per cent. No evaporation could then take place, and temperatures would prove fatal which could be endured with impunity in dry air. When it is dry and hot, one feels cooler during exercise in the sunshine and open air than when sitting in the house. Why ? In the vapor-laden atmosphere of the oceanic tropics we find a condition which interferes seriously with active bodily exercise. In Meteorological Stations, relative humidity is usually determined by the psychrometer (si-krom'e-ter), or the wet and dry bulb thermometers, shown in Fig. 145. The bulb of one thermometer is covered with clean unstarched cotton cloth, which dips into a vessel of rain or distilled water. By capillary action the cloth is always kept wet. Evaporation of the water cools the bulb, the heat of evaporation being taken in part from it. If the air is dry, evaporation goes on more rapidly, and the depression of the mercury column is greater than when the air is nearly saturated. tioned. For example, in a certain case, the dry bulb read 70°, the wet bulb 63-2°, and the hygrometer at the same time showed the dew-point to be 58°. The wet bulb there- Unfortunately, this factor is different for different temperatures, so it must be determined for all ordinary temperatures. The numbers obtained are called Glaisher's factors. They are given in the table below : If the temperature were 26° Pahr., the bulb would be covered with ice. In freezing weather it is better to remove the cloth and wet the bulb, allowing a thin film of ice to form upon it. If the wet bulb reads 24-5°, then the dew-point would be (26—24-5) x 6-3 = 9-4 degrees below the air-temperature. The dew-point would therefore be 26—9-4 = 16-6. The value of the factor for 26 is taken midway between the values 6-1 and 6'5 in the table. This method is not quite accurate for low temperatures. The Sling Psychrometer. — The psychrometer is most trustworthy when used in the wind. The air immediately around the wet bulb becomes moist, and evaporation from it will depend upon the quickness with which this air is removed by wind. The humidity of the air out of doors is therefore determined by means of a psychrometer in which the wet bulb is moved through the air until it shows a constant reading. A simple and inexpensive whirling psychrometer — consisting of two thermometers with the degrees marked on the glass tubes and mounted securely on a light brass back — is used by the officers of the United States Signal Service. One thermometer is lower than the other, so as to bring the bulbs in different strata of air, and the apparatus is whirled about the person by means of a string. When wet, the muslin-covered bulb will fall to its permanent temperature in about two minutes. A School-room Psychrometer. — The pupil may make a good psychrometer with two thermometers which read alike, and which can be bought for less than a dollar apiece. Any tinner can remove some of the metal around the bulbs so as to expose them similarly and permit the wrapping of one with cloth. Daily observations on the condition of the air in the school-room and the determination of the dewpoint will be of interest to the pupils. The Pressure of other Vapors corresponding to different temperatures has been carefully measured. In the table below, the values for four are given. The pressures are in centimetres of mercury, and the temperatures are in Centigrade degrees : Any liquid boils in open air when its vapor pressure equals the pressure of the atmosphere. The bubbles which form in the liquid then pass off freely. In the table above, it will be observed that at 100° (the boilingpoint of water in open air) the vapor pressure of water is 76 centimetres (30 inches) of mercury. The vapor of alcohol will have a pressure of 76 centimetres of mercury at a temperature a little below 30°, the pressure at 80° being 81'3. The boiling-point of alcohol in open air is therefore a little below 80°. It is found by experiment to be 78°. Ether vapors have a pressure of 91 centimetres of mer- VAPOR PRESS LJHE8. 267 the vapor presses the mercury downward. The water should be added in small quantities until the top of the column is perceptibly moist, which shows that the vacuum space has been saturated. The addition of more water would produce no further depression in the column, except such as might be due to the mere weight of the water. Introduce alcohol in the same way into another tube (C) and the column will be depressed still more. Ether in a third tube (D) will cause a still greater depression. If the temperature of the mercury in the tubes is 20° C., which is a common temperature in school-rooms, and if all the air is removed from the mercury and liquids, the columns into which the three liquids were introduced will be depressed 1-7, 4-5, and 43'3 centimetres. These are the values for the vapor pressures at 20° given in the preceding table. The fourth barometertube (A) is also depressed 0-004 centimetre by the mercury vapor above it. This amount is hardly perceptible to the unaided eye. QUESTIONS.— What is the source of atmospheric vapor ? When may the atmosphere be said to be saturated f Explain the relation between saturation and evaporation. Define humidity. How may the humidity of the air be measured ? State the number of grains to a cubic foot of saturated air at 0° Fahr. ; at 80. What does the difference prove ? Explain what is meant by the dewpoint. If the air is cooled below the dew-point, what takes place ? Describe Regnaulfs hygrometer, for determining the dew-point. How may a simpler apparatus be easily constructed ? What is meant by relative humidity ? When the relative humidity is low, is the air moist or dry ? Is discomfort experienced ? State a reason for your answer. Can high temperatures be better borne in dry or saturated air ? How is the relative humidity determined by the officers of the United States Geological Survey ? Is it possible for you to construct a fairly accurate psychrometer ? How would you determine the dew-point from the readings of your instrument ? What are Glaisher's factors ? Suppose your dry bulb to read 26° Fahr., and your wet bulb 24'5. what would be the dew-point ? When may a liquid be said to boil in the open air ? What is the vapor pressure of water in inches of mercury at 100° C. ? Of alcohol ? Describe an experiment illustrating the vapor pressure of water, alcohol, and ether. Heat may be produced in a variety of ways by the performance of work. For example, a metal button may be rubbed against a board or woolen cloth, as shown on page 40. The force required to make the button slide may be measured in pounds weight by means of a spring-balance, and this force, multiplied by the distance in feet over which it is exerted, will give the work done in foot-pounds. The button will quickly become warm, and if dropped into water will heat it. Some of the heat produced is lost in the wood or cloth, which also becomes warm. If the friction is continued, the metal will keep warm indefinitely. This shows that heat is being continually produced by the operation, the button soon cooling to the temperature of surrounding bodies when the friction ceases. Friction is a widely known Source of Heat. Even savages are familiar with the principle, and obtain fire by rubbing together pieces of dry wood. In a rapidly moving railway car, the heat produced by the friction of the axle turning in the box sometimes sets fire to the oily cotton-waste contained in the lubricating chamber, occasioning what is known as a " hot box." Ice itself may be melted by forcibly rubbing two pieces together at a temperature below the freezing-point. Count Rumford observed that, in drilling a cannon, the metal became very hot. He surrounded the gun by a box containing about 30 pounds of water, which was heated to the boiling-point in two hours and a half. The drill was driven by a horse working on a capstan-bar. It is thus evident that food may be cooked and houses heated by steam generated by the work of horses. But, as Count Rumford observed, this would never pay, since more heat could be obtained by burning the food of the horse than from his work. Joule's Determination of the Mechanical Equivalent of Heat. — The number of work units required to generate one heat unit — i. e., the number of units (foot-pounds) of energy equivalent to a unit quantity of heat — was determined experimentally by Joule (jool). He employed a copper vessel, B, filled with water and provided with a brass paddle-wheel, arranged somewhat like a churn. The paddle was driven by two falling weights, E and F, which were MECHANICAL EQUIVALENT OF HEAT. suspended from rollers connected with the pulleys C and D, provided with friction- wheels. Cords wound on these pulleys were passed around the vertical paddle-shaft A. The two weights were on opposite sides of the churn, in order to avoid friction of the paddle-shaft in its upper bearing. When the weights fell and the paddle revolved, the water was heated by friction. A thermometer, T, indicated its temperature (see Fig. 147). Various liquids were tried, and it was found that for every heat unit produced, 1,390 work units had been expended on the liquid by the falling weights, which were wound up again as fast as they reached the ground. The heating of one pound of water through one degree Centigrade is mechanically equivalent to the lifting of 1,390 pounds through a vertical distance of one foot, or of one pound 1,390 feet. A laborer can perform 723.000 foot-pounds of work in ten hours, thus working at the rate of 20 foot-pounds a second. If such a workman were to be set to heating water by turning the crank of Joule's apparatus, he would produce one heat unit for every 1,390 work units in a day's work. In ten hours he would generate heat enough to raise the temperature of 518 pounds of water 1° C. The expense of heating water by this method would be enormously greater than by means of burning coal. The wages of the laborer would be at least one dollar, while the coal required to produce 513 heat units would be only about one ounce (see page 271). The total daily mechanical and heat work of the human body is estimated at 7,216,000 foot-pounds, which, if expended in lifting the body, would raise it six miles against gravity. Heat produced by Collision. — If a bullet from a heavily loaded rifle be fired into dry sand, it will be found to have become hot, or even fused. A rod of iron can quickly be raised to a red heat by the blows of a steam-hammer, and a marked rise in temperature is noticeable in lead pounded on an anvil (see page 40). Before lucifer-matches were invented, the blacksmith used to ignite sulphur to kindle his forge-fire with a nail hammered to a red heat. The old flint-lock gun was discharged through the agency of heat evolved by the striking of flint and steel together ; the heat ignited the particles broken off by the blow, producing sparks which fired the powder in the pan. The steam-hammer and the rifle-ball might have acquired the velocity with which they strike by falling in a vacuum from a certain height, and the work which is done in the blow of either may be measured by the work required to lift the moving body in question to this height. A rifle-ball, for instance, would acquire a velocity of 1,500 feet a second by falling in a vacuum through a distance of 35,000 feet, or over 65 miles. If the ball has a weight of -fa pound, and strikes with a velocity of 1,500 feet a second, the work done in collision is 35,000 x -^, or 2,187 foot-pounds. (See the example on page 99.) Since we know by Joule's experiments that each 1,390 work units is equivalent to one heat unit, the heat liberated will be fif £M °r 1'57 heat units. If we assume that half the heat is generated in the lead, the other half being imparted to the sand, then the lead will receive 0'785 heat unit. How much would the temperature of the lead rise? COMBUSTION. Such experiments as that just described help to explain the nature of heat. When the mass in motion is suddenly stopped, the molecules of the body are thrown into vibration (see page 37). Vibration of their particles may thus be induced by rubbing bodies together, or by impact. Heat due to Combustion. — When carbon burns, the chemical action is a combination of the carbon-particles with oxygen-particles. They fall together, as bodies fall to the earth, forming carbon dioxide (carbonic acid gas). It is found that the complete combustion of a pound of charcoal to carbon dioxide produces 8,080 heat units, or enough to heat 8,080 pounds of water 1° C. Since one heat unit is equivalent to 1,390 work units, the heat produced by the combustion of one pound of coal is equivalent to 8,080 X 1,390 = 11,231,000 work units. If the pound of coal should fall through the distance of 11,231,000 feet, or 2,127 miles, with the acceleration which it has at the earth's surface, the heat produced on striking would be equal to that evolved by the burning of a pound of coal. The same heat would be produced by the falling of 100 tons of 2,000 pounds each through 56 feet. The following table gives the heat produced by the burning of a pound of various substances, and in the third column is stated the distance through which 100 tons must fall to yield the same heat : As in the operation of boiling, these combustions go on in air at definite temperatures. The bodies must be raised to the proper temperature before combustion takes place freely. The temperature at which iron will take fire and burn in air is higher than that necessary for charcoal. The coal, mingled with a fuel mixture, is tightly packed in a cylinder of heavy copper, C, having a length of four inches and a diameter of f to \| inch. This cylinder is supported in a socket soldered to the bed-piece D. An outer cylinder, A, about 5f inches long and 2 inches in diameter, sets down over the fuel cylinder, and locks to the bed-plate as the bottom of a lantern locks to the globe. Four brass springs Gr serve to guide the cylinder A to its place, in order that the parts may be quickly fastened together. The fuse / is ignited, and, before the fuel begins to burn, the cylinder is locked in position and the whole apparatus is plunged is opened at the top, and water rises and fills the whole apparatus. This should be blown out and mixed with the external water, in order to secure a uniform temperature. The temperature of the water having been read just before the operation, and subsequently at its close, the amount of heat liberated by the combustion is readily ascertained. The fuel mixture consists of three parts by weight of potassium chlorate mixed with one part of niter. These substances should be in powdered form, dry, and thoroughly mixed. The mixture must be handled with some care. For each part of pulverized coal, about ten parts of the fuel mixture are required. Not over three grammes of coal can be used at one charge, and this should be tightly packed to prevent too rapid combustion. ANIMAL HEAT. 273 midway in a pair of pliers or a vise, and burn off the external coating of the salt from one end. Insert the unburned end into the charge. The fuse will burn slowly down to the part still coated with the salt, and thus give time to place the furnace in position under water. On a damp day, the fuse is likely to fail unless gently warmed. most impressive one. If the whole apparatus, including the vessel B, weighs 1,260 grammes, the heat required to raise its temperature 1° C. (as it is of copper) will be 1,260 X 0-0952, or 120 heat units. If the vessel contain 3,000 grammes of water, then for each degree of rise in temperature the heat required would be 3,120 heat units. A correction should: yet be made for the heat generated by the fuse. This is best done by tearing four or five fuses to shreds, and packing them in a charge. The additional heat produced will be due to them, and the amount due to one can readily be found. Animal Heat. — In all the organs of animals, oxidation, or burning of organic matter derived from food, is going on. The oxygen is taken into the blood through the lungs, and is evenly distributed to all parts of the body. When an animal is at work, it requires more of this oxygen, and hence breathes faster and consumes more of the organic tissue than when at rest. The chemical products of the oxidation taking place in the body, like those of ordinary combustion, are carbon dioxide and water, which pass off in part in the breath and through the skin. It is this oxidation that produces the heat of the body. In the severe cold of arctic regions, life consists largely in an effort to eat and digest food enough to maintain the normal temperature. The Eskimos sustain their vital heat by a diet of fish-oil and seal's blubber, greasy food being rich in carbon. a standard temperature is maintained — but this standard differs in different species. Birds and mammals, having a high vital heat, are classed as " warm-blooded animals." The mean temperature of some birds is above 111° Fahr. The standard in man is 986°, and any deviation from this standard is regarded as a sign of disease ; temperatures below 97° Fahr. or above 106° Fahr. are extremely dangerous to life. Exposed parts, however, such as ears and fingers, are constantly cooled below the normal temperature of the blood and internal organs. Eeptiles and fishes have low bodily temperatures, and are hence called " cold-blooded." LAVOISIER'S EXPERIMENT. — Lavoisier (lah-vwah-ze-ay1) imprisoned a guinea-pig in a box surrounded by ice, placing the box in a room at the freezing-point. The heat of the animal's body fused 40227 grammes (0'887 pound) in ten hours. To fuse one pound of ice requires 79 heat units ; hence the animal produced 79 x 0'887 = 70 heat units in ten hours. This would be equivalent to 1,390x70 work units, or 97,300 foot-pounds. The guinea-pig weighed four pounds. If the work had been employed in lifting him, it would have raised him through aif Qa = 24,325 feet, or 4-6 miles in ten hours. Ten hours = 36,000 seconds. Hence the work performed in each second would have lifted the animal's body flffo = 0-67 foot, or about 8 inches. Plant Temperature. — It has long been known that plants evolve heat in connection with flowering, and this heat has been found to depend on the chemical processes which take place within the plant, transforming the matters derived from the soil into starch, sugar, and other products. By placing the bulb of a thermometer in contact with blossoms of Arum under a bell- jar, it has been established, not only that they have a temperature higher than that of the air, but also that the evolution of heat is variable. At 3 p. M., the air temperature being 15'6° C., the temperature of the flowers was observed to be 16-1° C. ; at 5.45 and 6.15 p. M., when the air temperature had fallen to 15°, the thermometer in contact with the flowers recorded respectively 19-8° and 21°. HEAT BY COMPRESSION. 275 A liquid in which the yeast-plant is growing, acquires a temperature above that of the air. The same is true of germinating seeds, as illustrated in the malting of barley. Corn in the act of germination rises in temperature from 6'25° to 7'5° C. above the air ; clover, 17'5° C. Plants sometimes have a temperature lower than that of the air, and hence may suffer from frost when the temperature of the air is above freezing. The mean temperature of the trunks of trees is found to be higher than that of the air in autumn and winter, and lower in spring and summer. Heat by Compression. — When a body, which expands when heat is applied to it, is compressed, it becomes hot, and gives off heat to surrounding bodies. Bodies which contract on being heated, become cool when compressed. By violent and quick compression, enough heat can be set free from air to ignite tinder. This is done with the Pneumatic Syringe, consisting of a glass barrel and tightly fitting piston (see Fig. 107, page 205). In the extremity of the piston is a small cavity, in which some tinder is placed. When the piston is driven rapidly down, the air in the barrel is compressed, muscular energy is transformed into heat, and the tinder is set on fire. QUESTIONS.— How may heat be produced by the application of work ? What is Friction ? Explain the heat of friction. State some familiar instances in which heat is produced by friction. How do savages kindle fires ? How great a heat has been produced by boring a cannon ? Explain Joule's method for determining the mechanical equivalent of heat. How many work units were found to be equivalent to a heat unit ? Give some familiar examples of the production of heat by collision or percussion. How does a rifle-ball acquire the velocity with which it strikes, and how may the work implied in its blow be measured ? Suppose an ounce bullet of lead to acquire a velocity of 1,500 feet a second by falling through a distance of 35,000 feet ; what will be its rise in temperature when it strikes the ground ? Does this imply that the lead ball may fuse ? Describe the combination of elements that occurs in the combustion of coal. Give the value in work units of the heat produced by the combustion of a pound of coal. Describe the apparatus and the process by which the heating power of coal may be determined. What is Animal Heat, and to what is it attributable ? Compare the chemical changes taking place in the living body with ordinary combustion. How is animal heat sustained amid arctic cold ? Why are not meat and greasy food an appropriate diet for summer ? Explain why a standard temperature is maintained in all animals. What is said of animal heat in different species ? State the normal temperature in man, and deviations that are dangerous. The mean temperature of birds. Narrate the results of Lavoisier^s experiment in regard to animal heat. What has long been known in connection with plants ? On what does the heat of plants depend ? Do plants ever have a temperature lower than that of the air ? Illustrate. What can you say of compression as a source of heat ? Heat always tends to pass from warmer to colder bodies. If several bodies near one another have different temperatures, those that are hot become colder, and those that are cold become warmer, until all have a common temperature. If all bodies had the same temperature, we should know nothing of heat. This equalizing of temperatures is brought about in three ways, viz., by Conduction, by Convection, and by Radiation. Conduction. — Thrust one end of a pin into a gas-flame. It will quickly become too hot to be held in the hand. The heat enters the metal pin at the end kept in the flame, and is transmitted along its whole length. A splinter of wood, a roll of paper, a glass tube, or a platinum wire, may be held with comfort by one end while the other is burning or fusing. The brass pin is said to be a letter conductor than the glass tube or platinum wire. Among metals, silver, copper, and gold, are examples of good conductors ; while bismuth, German silver, and platinum, are bad conductors. You can understand why articles made of certain metals feel intensely cold in winter. It is because they conduct the heat of the hand rapidly away. The principle upon which heat is conveyed by conduction is that of communication from particle to particle of the body receiving it. As each particle is set in more violent motion, it imparts this motion to the more slowly moving particles next to it, these to others, and so on, until those farthest from the source of heat are reached. The Principle of Conduction applied to Clothing. — When heat is being drawn rapidly from our bodies, the sensation of cold is produced. Bad conductors should, therefore, be chosen for clothing materials, that the animal heat may be retained about the body and dangerous chilling prevented. Wool and silk meet this condition perfectly, and cotton is to a certain extent safe ; but linen is a good conductor, and should never be worn next the skin, as it cools the body too rapidly in perspiration. Hair is a bad conductor, and, hence is an equally good protector against heat and cold. Explorers, in tropical as well as arctic regions, allow the hair and beard to grow. On the approach of winter, Nature provides for the protection of the lower animals by a heavy growth of hair, wool, or feathers, and by a jacket of fat, which is also a non-conductor. Conduction in Liquids. — Liquids, as a rule, are poorer conductors than most solids. Fill a test-tube with water, as shown in Fig. 150, place a fragment of ice at the bottom, and hold it down with liquids. The stem of an air thermometer passes through a cork fitted into the neck of a glass funnel. The lower end of the stem dips into a vessel of water. Fill the funnel with water so that the bulb is covered to the depth of half an inch. Pour a little ether upon the water in the funnel and ignite it (after having stoppered and removed the ether-bottle). While the surface of the water is considerably heated, the thermometer will be but slightly affected. This shows that heat penetrates water by conduction very slowly. poor conductors. Snow is a bad Conductor, and hence is popularly said to keep the earth warm. Its flakes are formed of crystals, which collect into feathery masses, imprisoning air, and thus interfere with the escape of heat from the earth's surface. The winter dwellings of the Eskimos are shielded from the cold by their snow covering. Hunters surprised RADIATION OF HEAT. 279 by night in the forest dig holes in the snow for protection, and the instinct of certain animals leads them to take advantage of the same shelter. A covey of grouse will dash into a snow-bank, and remain there in safety when the outside temperature is dangerous to life. Convection. — Liquids and gases are heated mainly by Convection, or transmission by means of currents. The air immediately in contact with a hot stove, being heated and thereby made less dense, ascends, and is replaced by colder and denser air from below. The warm column rises to the upper part of the room, and then, descending beside the walls, loses part of its heat and approaches the stove again along the floor. Similar currents are produced in a test-tube or tall beaker of water when heated over the flame of a spirit-lamp. The currents can be made apparent by placing a little bran or sawdust in the water. Radiation of Heat. — If we stand in front of a fire or hot stove, we experience a feeling of warmth. This is not due to the fact that the air in contact with us is warm, since if a screen be interposed the heat ceases to be felt. Such transmission of heat is known as Eadiation. The pupil must understand, in this connection, that the heat of the radiating body is wholly transformed, at the instant of radiation, into Radiant Energy (see pages 38 and 293). Throughout the space between the radiating and receiving object, the radiation is a form of energy entirely distinct from heat. The heat of the open fire, for example, transformed into radiant energy as just stated, passes on to us as radiant energy, and is retransformed into heat when it strikes our bodies. Radiation, therefore, strictly speaking, is the transmission of radiant energy, and not of heat. For the sake of brevity, we speak of heat radiation. The Power of radiating Heat varies in different bodies. Lamp-black, paper, and glass, are good radiators ; polished tin and silver, the reverse ; but any metal that is painted becomes an excellent radiator. Water will remain hot a longer time in a smooth silver cup than in a china one, provided neither is in contact with a conductor. The hearth-stone, when the fire is lighted, receives heat abundantly from the blazing fuel and radiates it freely to the surrounding air. Why does the hearth-stone now feel warmer to the bare foot than the rug? Good radiators are also good absorbers, and vice versa. The bottom of the tea-kettle is allowed to remain thinly coated with soot to counteract the non-absorbing property of the bright new surface. A very thin film of metal interferes with radiation and absorption. The Chinese are aware of this, and gild their silk umbrellas to keep out the heat of the sun. Radiation in a Vacuum. — If a thermometer be sealed into a glass globe, the mercury-bulb being at the center of the globe, and if the globe be then exhausted as completely as possible, heat will nevertheless affect the thermometer even better than when the globe is filled with air. This may be shown (Fig. 153) by dipping the globe into hot water. The thermometer will at once rise. A hot cloth wrapped around the thermometer stem, outside the bulb, will not appreciably affect the instru„ ._„ T nient; but, if the cloth be wrapped around the globe, MOMETER IN A a rise will instantly be observed. This shows that VACUUM. the heat is radiated from the sides of the globe to the thermometer-bulb, and is not conducted along the stem. Solar heat may be concentrated upon the bulb by means of a lens ; light and heat will both traverse the so-called vacuum. Law of Distance. — A hot ball of metal transmits heat in all directions, and will cool unless continually supplied with heat. A certain amount of heat leaves the ball during each second. Imagine a spherical concentric surface surrounding the ball, its radius being three feet (Fig. 154). All the heat which leaves the ball each second will pass through this surface each second, if the intervening medium is not heated. If we imagine a second concentric spherical surface, having twice the radius of the former, the heat which passes through the first surface every second would also pass through the larger surface in the same time. But the outer surface has four times the area of the inner, since, by a geometrical law, the surfaces of spheres are as the squares of their radii. The heat which would fall upon a unit area of the inner surface would therefore spread over four units of area at twice the distance, nine units of area at three times the distance, etc. Hence the heat per unit area at distances 1, 2, 3, 4, will be in the ratio of 1, ±, ^, -fa etc. The heating effect of a small radiant mass upon a distant object would thus vary inversely as the square of the distance. A similar law applies in the case of light and sound radiated from a point. Law of Cooling. — A hot body surrounded by cooler bodies radiates its heat and cools down to the temperature of its surroundings. When the difference in temperature is not over ten degrees, the heat radiated per minute (and therefore the fall in temperature per minute) is very nearly proportional to the difference in temperature between the hot body and the surrounding bodies. When a body is exposed to any source of heat, it rises in temperature, but at the same time it begins to radiate more heat. It will finally reach a temperature at which the amount of heat radiated per second will equal that received in a second. Its temperature will then cease to rise. In winter, heat radiates from the human body more rapidly than in summer, because the difference in temperature between the body and the surrounding air is then great. In the arctic regions, the drain upon the animal heat of the body is very severe, and a large part of the energy of the inhabitants is expended in keeping themselves warm (see page 273). gish and indolent in their habits, in order to avoid overheating. QUESTIONS.— What is meant by the diffusion of heat ? Explain what takes place when several bodies having different temperatures are brought near one another. By what three processes are temperatures equalized ? Describe the principle and effects of Conduction. Mention some poor conductors ; some good conductors. Explain why certain metallic articles feel intensely cold in winter. Why are cooking utensils provided with wooden handles ? Are stone and marble good conductors ? Prove it. What lesson may you learn from this ? Fire-brick is a bad conductor : why are stoves and furnaces lined with it ? What can you say of the relative value of materials used for clothing ? Why is an eider-down quilt incomparable as a cover at night ? What is the value of hair ? How does Nature protect the lower animals from cold ? Do you think the bark of a tree fulfills any such purpose ? Do fur garments impart heat to the body ? Why is flannel used to wrap ice in summer ? Which are the better conductors of heat— liquids or solids ? Liquids or gases ? Prove that water is an imperfect conductor. Illustrate the non-conducting property of snow. Did you ever notice in a building heated with steam that the pipes are wrapped with asbestos or felt and covered with canvas ? Why is this ? Describe Convection ; how may it be illustrated ? Explain Radiation. Of what is it really the transmission ? Exactly how is heat communicated from hot objects to our bodies ? What is Radiant Energy ? Show how the power of radiating heat varies in different bodies. What is the relation between radiation and absorption ? The conducting pipes in steamengines are never painted ; why ? Prove that radiation takes place in a socalled vacuum. State the law of distance in regard to radiation ? How does heating effect vary ? When does the temperature of a body exposed to heat cease to rise ? Demonstrate the law of cooling, and apply it in the case of radiation from the human body in winter. ISOTHERMS AND ISOTHERMAL SURFACES. Isothermal Lines. — If at any time the temperature of the air were observed over the whole surface of the earth, and the temperatures taken were recorded on a globe or map of the world, each in its proper place, there would result a series of places in both the northern and the southern hemisphere at which the temperature would be 70° Fahr. Lines connecting these points would coincide roughly with parallels of latitude. Between these two lines, in a belt covering the equatorial regions, the temperatures would be above 70°, while for points nearer the poles the temperatures would be lower. A line connecting a series of places whose mean temperature is the same is called an isotherm, or line of equal temperature. The position of isothermal lines is continually changing. If a thermometer which now reads 70° should in a few hours read 80°, it would show that the isotherm of 70° had moved to a higher latitude. It often happens that when it is growing warmer in New York, it is growing colder in Ohio, and vice versa. At points on the earth where day is dawning, these lines are generally moving away from the equatorial regions ; while 180° distant, where evening is coming on, the lines are moving toward the equator. These general movements are modified by storms and air-currents, so that the lines are continually shifting to and fro in a very irregular manner. Isothermal Surfaces. — Suppose the temperature of the air at the earth's surface is found to be 70° at some station. If the thermometer is carried up into the air, from this station, it will generally show a colder temperature. At the height of 1,000 feet, it would have to be moved toward the equator in order to register again a temperature of 70°. If we suppose the thermometer to continue to ascend, while at the same time moving southward in order that a temperature of 70° may be maintained, we imply that it ultimately reaches the equator. If the southward direction is still continued, it will be necessary to approach the surface of the earth in order to maintain a constant temperature of 70°, and we shall finally reach it at the southern isotherm of 70°. A thermometer might thus be carried from any point on the northern isotherm due south, in some such path as that described, and finally reach the southern isotherm, indicating at all points on the route a temperature of 70°. If the journey were conducted a few feet below the surface of the earth, the temperature would fall ; but, toward the equator, we should find the soil warmer. A subterranean path connecting the two isotherms might be found, where the temperature is 70°. This path would lie near the surface, but somewhat deeper at the equator than at higher latitudes. Clearly, then, we have here an isothermal surface, surrounding the earth at its equatorial region, and having a shape somewhat like that often given to a finger-ring (Fig. 155). This surface is continually fluctuated into irregular billows, by clouds, storms, and currents of air. The isothermal lines drawn in physical geographies are the lines in should start with a thermometer at the surface of the earth, within the equatorial ring of 70°, and carry it downward a few inches or feet into the soil, the temperature would fall, perhaps to 70°. While descending through twenty or thirty feet, the temperature would continue to fall, but thereafter it would rise, as we approach the hot interior of the earth. At a depth of perhaps 800 feet, the temperature would have risen to 70° again. Here we are on another isotherm of 70°, surrounding the interior hot core of the earth. This surface is probably wholly within the earth, excepting where it may be carried up by a hot spring or volcano. Within this isotherm will be others, having higher temperatures. Isotherm of — 2O° Fahr. — In the equatorial region of the earth, a temperature of —20° would never occur, either at or below the earth's surface. In the arctic regions, the air falls far below this temperature. If we bore into the earth there, it will in general grow warmer as we go down, until a temperature of —-20° is reached. At lower depths, the temperature will be higher. If we follow the isotherm Of _ 20° southward, it will finally come to the surface, then rise into the air, and envelop the equatorial regions of the earth at a point far above the isotherm of 70°. To the southward, the isotherm of —20° again dips to the earth, and holds a part of the antarctic land, like that of the arctic region, in its cup-shaped basin. It could, however, never enter unfrozen water (why?), but would in arctic seas lie within the ice, or in the air very close to the water. Frequently in winter the isotherm of —20° dips to the earth in a local down-pour of cold air in the latitude of Chicago, and even occasionally as far south as St. Louis. In Fig. 155, the isotherms are drawn as if the arctic regions were occupied by land ; but of course they are not drawn to proper scale. Other isotherms between those of —20° and 70° are shown, and it is left to the reader to understand them without further explanation. It will be seen that every isothermal surface in and around the earth, including all artificial sources of heat, is a completely closed surface, and surrounds a region where the temperature is either warmer or colder than it is on that surface. Heat-Engines. — Heat is extensively utilized to save man labor. A heat-engine is a machine in which heat is transformed into mechanical energy, and is thus enabled to perform work by means of the expansive force of steam, hot air, or exploding gas. The expansive force of powder when ignited in a gun-barrel imparts motion to the bullet — hence a gun is a simple heat-engine. The oldest heat-engine known is described in the " Pneumatics " of Hero, a Greek philosopher who experimented at Alexandria about 150 B. c. It consisted of a vessel of water, A B, closed securely by a lid, and communicating through the tube on the right with a hollow ball above. Opposite was a pivot resting on the lid, and the ball was provided with two jets, bent at right angles near their outer edges, as shown in Pig. 156. As soon as heat was applied to the vessel, steam entered the ball and issued violently from the mouth of each jet, causing the ball to revolve. Hero's was a simple rotary engine. Little attention was given to the development of the heat-engine from the time of Hero until the seventeenth century. The study of the application of steam was then resumed, and successive improvements have been made in steam motors by various investigators until the present perfection has been attained. The Modern Steam-Eiigine utilizes the pressure of steam for doing work. The steam is generated in a boiler, B (see Fig. 158), and is conveyed to a cylinder, C, through a steam-chest, S. The steam-chest contains a valve, V, which ure of the steam is thus applied alternately on opposite sides of the piston, driving it to and fro. The power is o_ transmitted through the piston-rod R to the driving- A circular disk, e, is eccentrically mounted upon the shaft and can be rigidly connected in any desired position by a set screw. Surrounding the eccentric is a collar, within which the eccentric turns when the shaft is revolved. The other end, «, of the eccentric frame being connected with the valve- rod, it is evident that the valve will slide to and fro with every revolution of the shaft. At each stroke, the steam on the driven side of the piston is put in communication with the air and is swept out through the exhaustpipe E (Fig. 158). As here shown, the steam is entering the head end of the cylinder, and the crank end is connected with the exhaust-pipe E. The student should make a drawing showing the position of the valve on the return-stroke, when these connections are reversed. In some engines, the exhaust-pipe E connects with a condenser shown in the lower part of Fig. 158. The exhaust-pipe would be connected at E', leading the steam into a chamber, W, surrounded with water contained in a tank, T. Water is pumped into this tank and escapes by a waste-pipe. This water condenses the steam. At the same time an air-pump connected with the pipe P pumps air, water, or steam, from the condenser, delivering the water to a tank called the "hot well." The water required to supply the boiler is taken from the hot well by a force-pump or an injector. The effectiveness of the condenser is vastly increased by admitting water from the tank T into the condenser through a short pipe terminating in a bulb, or " rose," with fine holes for spraying the condensing steam. This supply is regulated by a valve controlled at F. As the pressure in the condenser is considerably below that of the atmosphere, the water will flow in if this valve is opened. Engines which exhaust their steam directly into the air are called Non-condensing Engines. The back pressure on the exhaust side of the piston is never less than the atmospheric pressure. In condensing engines, the back pressure is that of the condenser. This pressure will depend upon the temperature of the condensing water and the effectiveness of the air-pump. If the water entering the condenser contained no air, the pressure would be determined wholly by the temperature of the water. If this temperature were 60° Fahr., the pressure in the condenser would be about half an inch of mercury (according to the table, page 257, it would be O518 inch) or -fa atmosphere. The pressure in the condenser is usually about -fa atmosphere. In large stationary engines, and particularly where water is cheap, the condenser is an advantage. For the same boiler pressure, the effective pressure on the piston is increased by about -£,- atmosphere, as the back pressure is diminished by that amount. is at one point drawn down to a diameter of about ^ inch. The outer tube simply serves to protect the inner one from breaking at its narrow part. Force water through the tube from a hydrant. A break will be observed in the water column just after it passes the narrow part ; it will appear like snow-white foam. At the same time a rattling sound will be heard like that made when a jet of steam is discharged under water. If the section of the tube at a a is -^ of the section at the wide part, the velocity of the water-particles at the small section will be ten times as great as at the wide part, since the same amount of water passes through one section as the other in each second. The moving energy of a particle at the narrow part will therefore be 100 times as great as a moment later when it has reached the wider part. Just at the place where the tube widens, the water ceases to fill it if the hydrant pressure is sufficient. The swiftly moving particles in minute spherules shoot across the vacuum formed and bombard the more slowly moving mass in front, producing the sound heard and maintaining the width of the gap in the water column. The feed-water injector is a similar device. One form of it is shown at I (Fig. 158). Steam from the boiler passes through the tube K and escapes through a small cone-shaped nozzle into a slightly wider nozzle upon the feed-pipe J. The pipe J leads back to the boiler below the water-line. The two nozzles are inclosed by a pipe, P', which dips into the feed- water in the hot well. The steam rushes through the narrow opening, condensing to water as it passes through the feedwater, which must cover the gap between the two pipes, and goes back into the boiler, carrying the feed- water with it. The Governor is an ingenious piece of mechanism designed to make the engine run steadily by regulating the admission of steam (see G, Fig. 157). It consists of two heavy iron balls which revolve about a spindle driven by the engine, and which, under the influence of the centrifugal tendency, fly out from the spindle in proportion to the rapidity of revolution. In moving out, they act in a certain manner on the regulator of the engine, which may be a throttle- valve between the engine and the boiler, and cut off the supply of steam. As they fall toward the spindle, the valve is opened and steam again admitted. Air and Gas Engines include those machines in which the working element is air or some gaseous product of combustion. A piston may be driven with great velocity by the elastic force of heated air, or by the expansion of a mixture of gas and air at the moment of explosion. Otto's silent gas-engine is operated on the latter principle, a dilute mixture of coal-gas and air being ignited in the cylinder under a pressure of three atmospheres. A governor regulates the admission of the gas. Gas-engines possess an advantage not only in being easily made ready for use, but also in the limited amount of fuel consumed. THE NAPHTHA LAUNCH. 291 in a motor recently devised. The naphtha is confined in a tank. Gas coming from this naphtha is forced through a pipe to a burner, where it is ignited and heats a retort or ENGINE. coil, prominent in Fig. 160 on top of the engine. When the coil is sufficiently hot, liquid naphtha is forced into it. This at once vaporizes and expands, thus creating pressure on the cylinder, as indicated by a gauge, and this pressure is utilized to move the machinery. As the naphtha-pump is connected by an eccentric with the main shaft, at each revolution of this shaft naphtha is automatically supplied to the boiler. An injector communicating with the retort supplies a portion of the vapor regularly as fuel. The engine above described is used in the naphtha launches of the Gas-Engine and Power Company, of New York. There is freedom from the dirt inseparably associated with the use of coal, and the expense of running the engine is small. QUESTIONS.— Explain isothermal lines. Show how isotherms change their position. How are their general movements modified ? If a thermometer be carried upward from a point on the earth's surface, and then moved southward, how may a temperature of 70° be maintained ? How, after crossing the equator ? What are isothermal surfaces ? Are there isothermal surfaces within the earth ? Show how this may be. Trace the isotherm of 20° F. Construct a diagram illustrating approximately the isotherms of 20 and 70° F. What are Heat-engines ? Illustrate in the case of a gun-barrel. Describe the oldest known heat-engine. The modern steam-engine, reproducing the figure in its essential details. What is the eccentric ? the injector ? the governor ? State the difference between condensing and non-condensing engines. Explain the principle of air and gas engines ; of the naphtha-engine. Sum up the properties of heat you have become acquainted with in the preceding lessons. When is a body hot ? When cold ? When do bodies feel neither hot nor cold ? Sum up the general effects of heat. The temperature of a school-room in North Dakota was 60° F., while outside, the reading of the thermometer was 52° F. below the freezing-point. Express the difference in degrees Centigrade. Express 0° F. on the Centigrade scale. The extreme range of temperature at Werchojansk, in Siberia, is 185° F. Express this in degrees Centigrade ; in degrees Reaumur. Is this change in temperature as great as the difference between the freezing and boiling points of water? The temperature of the earth's crust rises about 100° F. for the first mile of descent toward the earth's center. How many feet of descent will involve a rise of 1° C. ? How many centimetres ? (See table, p. 540.) How many times its volume does water expand when converted into steam at 100° C. ? Under a pressure of one atmosphere, how many cubic inches of steam may be generated from two cubic inches of water ? If 51,000 cubic feet of steam be condensed, how much water will result ? If 50 grammes of ice at a temperature of — 10° C. are put into 400 grammes of water at a temperature of 80°, the temperature of the mixture will be 617°, what is the specific heat of ice ? Ans. 0'47. Careful experiment shows the specific heat of ice to be 0'489. . Which is warmer to the touch, a conductor or a non-conductor ? On what principle is the shell of a modern breech-loading shot-gun exploded ? On what principle was the old flint-lock discharged ? Why is glass so perfect a protector of young plants rooted in a hot-bed ? The mean distance of the sun from the earth is 93,000,000 miles ; that of the moon is 239,000 miles. If the sun were as near as the moon, about how many times as much heat should we receive from it ? The distance from New York to Chicago is 977 miles. Find the difference between the total length of the steel rails connecting these cities, on the hottest day in summer and that on the coldest day of winter, assuming the temperature to vary from 20° below zero to 90° above If the rails are 30 feet in length, what space must be left between the ends ? DUCTION AND TRANSMISSION OF LIGHT. Kelatioii between Light and Heat. — All bodies, at all times and at all temperatures, are in a state of molecular agitation whose energy is Heat (see page 37). Some of this energy, their molecules impart, in the form of periodic vibrations, to the ether, which is supposed to pervade all space, both inside and outside bodies, and to exist in the most nearly perfect vacuum which we can produce. The NOTE.— The following outfit, in part illustrated above, is suggested to the young experimenter : No. 1 represents a combination of cylindrical lenses designed to illustrate the correction of astigmatism (see page 349) ; 2, a Newton's disk and rotator ; 3, a double concave lens, mounted ; 4 and 5, glass prisms, mounted ; 6, a pocket microscope ; 7, a plano-convex lens ; 8, a convex mirror ; 9, a double convex lens or reading-glass ; 10, Prof. Mayer's he'liostat, described on page 299. The pupil is advised to supply himself with a complete set of six demonstration lenses, unmounted, a NicoFs prism, a concave and a convex mirror, a mirror of black glass, a three-inch prism, and a crystal of Iceland spar. This collection will be furnished by any instrument-dealer at a moderate price. Small concave and convex mirrors and burning-glasses may be purchased at the toy-stores for a few cents. The rotator and heliostat illustrated above are furnished at a moderate cost by Samuel Hawkridge, instrument-maker to the Stevens Institute, Hoboken, N. J. 294 LIGHT. energy of ether vibration, however, is not heat energy ; it is another of the forms described on page 38, and is called Radiant Energy. The process of emitting radiant energy is Radiation. The ether- vibrations pass off in all directions, by a species of wave-motion, with great velocity. If these waves impinge upon objects, the radiant energy is transformed, producing effects determined by the nature of the body upon which they fall. On the skin, they cause the sensation of warmth ; on a thermometer, a rise of temperature — indicating in each case that radiant energy has been turned into heat. But the most remarkable effect is that produced when the radiations strike the eye, and are converted in the mysterious structures of the retina into proper stimuli of the optic nerve fibers. When such radiations are between certain limits of wave-length, these fibers, thus stimulated, become the means of awakening in the brain the sensation which we call Light. As some air- waves do not excite sound-sensations because they vibrate too quickly or too slowly (see page 399), so there are ethervibrations which do not affect the optic nerve. "When vibrations are properly timed, very striking mechanical and chemical effects may occur. An army of men keeping step on a bridge set it into strong vibration, and may shake it down. In like manner, light- waves falling upon silver salts used in photographic plates, cause a vibration which shakes asunder the particles of which they are composed. A Luminous Body is one which emits light. When the light originates with the radiating body, the latter is said to be self-luminous. The sun, whose surface is composed of exceedingly hot and brilliant clouds, the flame of a candle or a gas-jet, a fire-fly, are self-luminous. Other bodies, like the moon and most of the objects surrounding us, are seen by reflected light, which originates in some selfluminous body. They are said to be illuminated. ent body would be invisible. Glass, water, and air are transparent. When glass or ice is pulverized, light is quenched by repeated reflections from the internal faces of particles which present themselves at all possible angles to the rays. Such a mass is said to be opaque ; it intercepts rays of light and casts a shadow. Snow or crushed ice united into a continuous mass by pressure becomes transparent. A translucent body allows some light to pass through, but objects can not be seen through it. Opaque Bodies become translucent, and even transparent, when in thin layers. The sun may be seen through a thin layer of silver deposited on the object-glass of a telescope, although a less brilliant body would be invisible. All substances, even those which are transparent, intercept some of the light which they receive. The sun's rays lose much of their brilliancy by passing through the earth's atmosphere. As we ascend above sea-level, less and less light is absorbed, and the heavenly bodies become more distinctly visible. PROPAGATION AND VELOCITY OF LIGHT. Light moves in Straight Lines. — When a beam of sunlight is reflected into a darkened room, its path is revealed by illuminated particles of dust. This path is observed to be straight. We see each point of every object by means of the light which it radiates. If light did not travel in a straight line through the sights of a rifle to the eye, it would be impossible accurately to direct the ball. Images by Small Apertures. — A result of the rectilinear path of light is shown in the formation of images by small apertures. If a minute opening be made in the side of a dark box or chamber, and the light which enters be received on a screen, images of external objects will be seen in form and color. The light which passes through the opening from each point of the object falls upon a definite point of the screen and on no other. The image is thus a continuous series of innumerable bright spots. The screen may be at any distance from the opening. The size of the as this distance increases. Pierce a sheet of paper with a pin and allow sunlight to pass through the opening and fall upon another sheet of paper. A round image of the sun will be seen. If a second hole be made, there will be two images, which will overlap if the screen be far enough away (Fig. 164). Continue to pierce holes near together. Each one will yield a new image. As the paper wears out and the holes break into one another, the screen shows a luminous patch of light. A window-opening may be supposed to be made up of an infinite number of small openings placed side by side, and the patch of sunlight on the floor to be an infinite number of overlapping images of the sun. Let the pupil explain why. The brightness of the image decreases as the opening becomes smaller. The latter may have any shape, if small ; but is incapable of producing an image, if large. Images of the sun may often be seen on the floor where sunlight streams through small apertures in the blinds, and on the ground where light shines through the foliage. In a partial eclipse of the sun, these images have been observed to be crescent-shaped. Why? Such images can be photographed by substituting a plate with a small opening for the lenses of an ordinary camera. PING IMAGES OF THE SUN. Velocity of Liglit. — Light travels in space with a velocity of about 186,000 miles a second. This fact was first determined by Koemer (ro'mer), a Danish astronomer, some two hundred years ago. He made observations on the nearest of Jupiter's satellites, which revolves round that planet as the moon does round the earth, and which at regular intervals passes behind or into the shadow of the planet and is eclipsed — that is, becomes invisible to an ob' server on the earth. / minutes and 36 seconds. As the revolutions of the satellite take place in exactly the same number of hours, the apparent lengthening of the interval between the eclipses can be explained only on the supposition that light from the satellite m occupies time in its passage through space to the earth, and that this time is lengthened by the motion of the earth away from the satellite. In traversing the distance E E', or twice the distance of the earth from the sun (186,000,000 miles), 16 minutes and 36 seconds are consumed. It was thus an easy matter for Roemer to determine how far light traveled in a single second. How is the apparent interval between successive eclipses affected as the earth moves back again to E f The velocity of light has been determined by other methods, with closely agreeing results. While one is pronouncing its name, light might travel eight times the distance round our earth. The remoteness of the fixed stars from us may be inferred from the fact that the time required for the passage of light from those that are more object sends rays of light in all directions. We see any point by means of a cone of rays whose vertex is at the point and whose base is the pupil of the eye. If we view the object from a different position, we see it by means of a different cone of rays, which, however, have diverged from the radiant-points. QUESTIONS.— What relation can you discern between Heat and Light ? What obvious distinction ? What is radiant heat ? Do all heat-vibrations affect the optic nerve ? Describe the effect of light on silver salts. As regards the production of light, how are bodies divided ? Distinguish between self-luminous REFLECTION OF LIGHT. and non-luminous bodies. How may non-luminous bodies become visible ? Whence does the moon borrow her light ? As regards the transmission of light, how are bodies divided ? What are transparent bodies ? Translucent bodies ? Opaque bodies ? How may opaque bodies become translucent ? Why are the stars more brilliant when viewed from a mountain-top ? Describe the path of light in a uniform medium. How is this path revealed in a dark room ? Prove that light travels in straight lines, from what is noticeable in rifle practice ; from the lengthening of shadows toward sunset. Explain what is formed on a screen opposite an aperture in the shutter of a dark room. On what does the size of the image depend ? On what its brightness ? How may images of the sun be formed ? What have you often noticed on the ground when walking through a grove on a sunny day ? What is the velocity of light ? By whom was it determined ? State the facts and reasoning by which the astronomer arrived at his conclusion. How long does it take the light of some of the stars to reach us ? If the course of light was not rectilinear, how long would it be in flashing around our globe ? The wild pigeon flies with a velocity of 100 miles an hour. If this rate of speed were maintained, how much time would the bird consume in making the circuit of the earth ? Why can every person in a large audience see a speaker at the same moment ? Does all light travel with the same velocity ? It does. Reflection of Light. — We have learned that light moves in straight lines and is radiated from luminous bodies equally in all directions. When the radiations or rays of light strike a polished surface, they are reflected and take a different direction. If a small opening be made in the NOTE.— In order readily to obtain a stationary horizontal beam of light for examination, Prof. Mayer has devised a simple form of the instrument known as the he'liostat (sun-placer) Fig. 167. It consists of a piece of board made of a size to fit the window selected for the experiments, pierced with a hole 5 inches in diameter to admit light to the darkened room. Iron brackets (C) 14 inches apart support a shelf 6i inches wide, on the outside edge of which a board (D) 7 inches high is screwed, parallel to the large board and 16 inches from it. On the shelf is placed a mirror (O) 6 inches square, standing at an angle and facing the opening into the room A beam of light is thrown upon this mirror from a second mirror above in such a manner that it is reflected through the opening horizontally into the darkened apartment. The upper mirror (6 x 10 inches) is movable, so that it can be adjusted to the movement of the sun in the heavens. shutter at S, sunlight entering with a velocity of 186,000 miles a second and striking a mirror (M), seems to rebound. S M is called the incident ray, and M S' the reflected ray. The point M is called the point of incidence, and a line N M, perpendicular to the mirror at that point, is called the normal at M. The angle S M N is called the angle of incidence, and the angle S' M N the angle of reflection. It is fastened on a board (N), to the back of which is tightly screwed a half-round flat piece of wood (G). This circular piece plays in a slot cut in a round length of hard wood, being fastened to the overlapping ends of the handle by an ordinary iron bolt and nut. A hole 1} inches in diameter is now cut in the windowboard and the handle fitted therein, as shown in the cut. Arrange the mirrors so that a round beam of light will enter the room, and turn the handle of the instrument, as necessary, to keep the beam in place. The size of the beam may be regulated by placing a piece of cardboard over the aperture, pierced as desired. In the heliostat of the instrument-makers, the sunbeam is kept in a fixed position by the action of clock-work. (See Mayer & Barnard's " Light," page 16.) With Prof. Mayer's apparatus (which any one familiar with the use of carpenter's tools can easily construct), and the few lenses, prisms, and mirrors, shown on page 293, the young pupil may perform for himself a series of simple and instructive experiments illustrating the phenomena of light. A slender beam of light may be admitted with the aid of the heliostat, and leisurely studied. A hand-mirror may be used to reflect it, and it may be thrown wherever desired ; or, if reflected from a small piece of looking-glass fastened over the wrist with warm wax, it will respond amusingly, on the wall or ceiling, to the pulse-beats. lie in a common plane. A ball thrown against a wall will rebound, but the angle of incidence is always less than the angle of reflection. A base-ball, suspended like a pendulum and striking against a wall to which it is attached (Fig. 169), will rebound very little, and the angle r will be much larger than i. If a more elastic ball be taken, the angles / will be more nearly equal. Evident- ly the ball and wall must be perfectly elastic in order to make the angles r and i equal. If, therefore, the reflection of light involves the rebound of elastic particles, as was formerly thought, they must be so nearly perfectly elastic that no difference between the angles i and r can be detected. Images by Plane Mirrors. — Images are formed by mirrors in accordance with the laws of reflection. Any radiant point 0, in front of a plane mirror, will radiate light in all directions. Part of the rays will strike the mirror and will be reflected the image 01 the point 0. We commonly say that we see the image at I, hut we are really looking at the point 0, by means of rays which, but for the mirror, would not have entered the eye. "We are really the subjects of an illusion as regards the position of the object which we see. The reflection of the sun from water often appears as a broad, illuminated patch of light. This is due to the fact that ripples or waves over a wide area present inclined surfaces, so situated that they reflect light to the eye. The rougher the water, the broader this illuminated area will be. Pig. 171 illustrates the reflection of sunlight from a wave surface. The reflection of a bridge from ruffled water often shows an obliteration of all horizontal beams or arches, because REVERSAL OF IMAGES. of the dispersion of the images. The images of vertical rods are elongated and indistinct at the ends only. This is due to the motion of the waves, which causes the reflected light, to vibrate to and fro, as will be understood from an inspection of Fig. 171. Reversal of Images. — If you place before a mirror your right hand grasping a pencil, the image will show a pencil in the left hand. This proves that an image in a mirror is reversed as regards right and left, although it looks like a correct portrait. Every wood-cut and type-face must be made in a reversed position. When held before a mirror, its image shows as a print from it will appear. Law of Least Time. — If a person were to run from a point A to a point D (see Fig. 174), over uniform ground, upon which he could move with a constant velocity, the journey could be made in the least time if the path were the straight line from A to D. If he were required to run from A to the wall B C, and then back to D, the journey would be made in the least time if the point m, where he is reflected from the wall, were so chosen that the two lines A m a minimum, Images formed "by Two Mirrors. — If a lighted candle be placed between two mirrors which face each other, the light will be reflected from one mirror to the other, each reflection giving rise to an image, which is an image of an image in the opposite mirror. If the mirrors are exactly parallel, the images will be on a common normal, and there will be an infinite number of them at regularly increasing distances from the mirrors. As some light is lost at each reflection, the images ^ jects, and notice the reversal of consecutive images. The observer may station himself behind one of the mirrors, and look through a pin-hole scratched in its back. If the mirrors, instead of being parallel, are placed so as to form an angle with each other, the images are limited in number. This principle is applied in the kaleidoscope (ka-li1 do-scope\ a tube com- CURVED MIRRORS. 305 monly containing three mirrors set at angles of 60°. Pieces of colored glass, free to move at one end of the tube, are seen through an eyehole opposite, multiplied by repeated reflections. Curved Mirrors. — The curved mirrors commonly used as lamp-reflectors are spherical— they are portions of the surface of a sphere. When light from a radiant-point at an infinite distance falls upon a concave mirror, the incident rays will be parallel, and will converge, after reflection, to the principal focus F. infinite distance on the convex side up to the mirror. If 0 is on the convex side, the rays will always diverge after reflection (Fig. 180). The object 0 moving from the mirror to an infinite distance on the convex side, the image i moves from the mirror to F. any position, the object and image may change places. If the object be placed where the image is, the image will be formed where the object was. This usually involves a reversal of the direction in which the light travels. A ray of light traversing any path, with any number of reflections, will if reversed retrace that path. Real and Virtual Images. — When all the rays of light diverging from any point of an object are by any means converged again at any other point, we have a real image of the radiant-point. When the rays from the radiant-point are so changed that they seem to have diverged from some other point in space, a virtual image is produced. This line is called a secondary axis. It has the same properties as a primary axis, and, like the primary axis, it intersects the mirror at right angles, so that a ray 0 M' will be reflected directly back upon itself. Rays parallel to this axis will, after reflection, converge to a focus at a point midway between M' and C. The image of the point 0 will be at a point i on the same secondary axis, and its position is determined as before explained (page 305). 0 and i are on opposite sides of the principal axis. Image of any Object. — In order to construct the image of any object, it is only necessary to locate the images of its extremities, or other principal points. This can be done by drawing secondary axes through those points. a b will be larger than the object. If you hold a concave mirror in your hand and look into it, you will see a magnified virtual image of your face. In like manner, if you should construct the image of an object placed directly in front of a convex mirror, you will understand why such mirrors give a diminished image ; but it must be remembered that an object at a distance from a concave mirror produces an inverted and reduced real image. This you can readily prove by standing near a window with a concave mirror in your hand, and casting the image formed of outside objects on a screen held just in front of the principal focus of the mirror. Can you construct a diagram to prove that this must be so ? MAGIC MIRRORS. 309 a small aperture in the center. The mirror reflects light into the patient's eye, and the examiner makes his observations through the opening from behind. Magic Mirrors. — The face of the ordinary Japanese mirror is slightly, though not uniformly, convex. This mirror consists of a thin disk of polished metal, ornamented in relief on the back. The portions of the mirror in front of the relief work become plane or nearly so in the process of manufacture, and hence reflect rays that are less divergent than those reflected from the parts that remain convex. If a bright beam of light be reflected from such a mirror, which is partly convex and partly plane, a more or less well-defined image of the raised ornaments on the back will appear on the screen. Mirrors possessing this physical peculiarity are called Magic Mirrors. single ray. QUESTIONS.— Describe the phenomena of reflection. How may a horizontal beam of light be obtained for study ? Describe Prof. Mayer's heliostat, and state its uses. Can you turn the ray of light from its course ? State the laws of reflection. What are rays called that strike a body ? Rays that are thrown back ? What can you say of the relative reflecting power of dull and polished surfaces ? Why is a room with white walls lighter than one papered with a dark pattern ? Can you tell why window-panes sometimes appear fiery red at sunset ? WThat is a Mirror ? On what principle do we see ourselves in a mirror ? How far behind a plane mirror does the image of an object appear ? How many kinds of mirrors are there as regards shape ? What relative position do the image and object occupy as regards the normal ? Show when they are equally distant from the mirror. Show how we are deceived in regard to the position of an object seen in a mirror. Describe and explain the common appearance of the reflection of the sun from waves. Why is there an obliteration of horizontal features in the reflection of a bridge from ruffled water ? Explain the reversal of images in mirrors. State the law of least time, and apply it to light. Describe the formation of images by two parallel mirrors ; by mirrors placed at an angle. What is the kaleidoscope ? What are curved mirrors ? Define the principal axis and focus. On what does the distance of the focus depend ? How far from a plane mirror is its focus ? Describe the reflection from a concave mirror. Discuss the relation between the positions of the object and the image when the former is beyond, at, and within the center of curvature. Where must the object be to have the rays di- verge after reflection ? What are conjugate points ? Distinguish between real and virtual images. What is the secondary axis of a mirror ? Describe images of objects placed directly in front of concave mirrors ; of convex mirrors ; at a distance from concave mirrors. What are magic mirrors ? Refraction illustrated. — Construct a rectangular box having one side of glass fastened by means of wooden strips laid in white lead. Throw a slender beam of light S (see Fig. 183), directed into the room by means of the heliostat, over the edge of the box and along the glass side. Note the point A where it falls upon the bottom. Fill the box with water, and cloud the water slightly with a few drops of an alcoholic solution of mastic. The beam of light will now bend at the water surface, and will proceed to a point B. Law of Refraction. — To explain the law of refraction, draw a circle having a radius of one unit, say an inch, foot, or decimetre, and having its center in the water surface at the point of incidence K, as in Fig. 184. The incident ray may be represented by a K, and a K 5 is the angle of incidence. Then the line a 1) is called the sine of the angle of incidence. This is abbreviated sin i. abbreviated sin r. It is found by careful measurements that when i changes, r always changes in such a way that sin i is always £ of sin r when light passes from air into water. If m K is the incident ray, then K o will be the same straight line. If the ray enters sensibly parallel to the surface, as in the case of v K, the angle of incidence is 90°, and the sine of i = 1, or v K. The refracted ray will pass along a line K u, so located that u z, or the sine of r = f of K v, which is the sine of the angle b K v. Strictly, the light can not enter parallel to the surface, but it may be directed into a globe half full of water. If the light enters at u, and is incident at K, it will pass out along the surface in the direction K v. Similarly, the light may be sent through the water along the lines o K or d K, when it will pass into the air along the lines K m and K a. appears shortened. The rod A D B (Fig. 185) is bent into the form A D B' when viewed from e. The plumb-bob w will seem to be at w', which is directly above w. The plumb-line appears straight throughout, but the part below the water appears shortened. The appearance of the rod may be found as follows : From e draw e o or e o', producing the lines indefinitely below the surface o' o D. With o and o' as centers, draw circles, each having a unit radius. Then the lines s s are the sines of the angles of incidence, and the refracted rays o' s' and o s' must be so drawn that s' s' is $ of s s. for large angles of incidence. It is on account of refraction that one must aim below the apparent position of fish in shooting or spearing them. Here, as in reflection of light, the eye always refers the direction of a body along the direction which the light from it has on entering the eye. Apparent Depth of Water. — If one stand in a pool of clear water, the depth of which is everywhere the same, the bottom will appear dished. The water will seem deepest just below the eye. A few feet distant, water four or five feet deep may seem not over a foot in depth. If, however, the bottom seems flat, the water would grow deeper as one went outward from the eye. Many persons are drowned by reason of these deceptive appearances. PHENOMENA OF REFRACTION. 313 the eye be placed near the water surface. Let a a (Fig. 186) be the water surface, and b b the bottom, e being the position of the eye. Then will b' b' be the appearance of the bottom. Draw lines from the eye to any points in the surface. At these points erect normals, draw circles of unit radius around them. The position of the ray in the water can then be found as before described. Produce this ray to the bottom b b. The point thus determined will seem raised vertically to the prolongation of the ray passing through e. An inspection of Fig. 187 will make it clear that we see the sun both before it rises and after it sets. Suppose the observer to be stationed at A. Rays from the sun, like S D, would not reach A at all, because the round earth is in the way; but rays like S C, passing through air of increasing degrees of density, are repeatedly bent toward the normal, until they reach the earth's surface at A. If the refractive power of air be subjected to constant modification, as by the warm currents rising from a hot stove, objects viewed through it will appear to have a wavy or tremulous motion. Total Reflection. — Light striking the water at any angle between 0° and 90°, will enter and suffer refraction, as explained. In Fig. 188, the paths of rays 1 m 1, 2m 2, 3 m 3, and 4 m 4, are shown. When the angle in the air is 90°, or z m S', the sine of the angle of incidence is the radius, and v w, which is } of the radius, will be the sine of r, or v m n. If the light were to be reversed in direction, each ray would retrace its entire path. If the incident ray were to sweep through the angle n m v, being always inci- The angle v m n is called the critical angle. If the incident angle in water is greater than the critical angle, total reflection takes place. TOTAL REFLECTION. side faces. The bottom presents a silvery appearance, like a mirror, and seems to be much narrower than the band of lines. The lead pencil shown in the figure is also invisible through the top face, by reason of total reflection from that face ; but it is seen reflected from the bottom face. In the top face, two sets of ruled lines are visible. The lower lines are seen directly through the bottom of the cube, their apparent position being changed by refraction. The upper lines are also the lines below the -cube, seen by total reflection from the back face. These two sets of lines are separated by the beveled edge of the cube. contact with air. The cube may be placed on edge and a beam of light (from a lens of long focus, or directed by the heliostat) sent into one face so as to strike an adjacent face from the inside. Total reflection of the beam will be seen, its track being revealed by a greenish color (see Fig. 190). Light under Water. — Light radiating from a point 0 (see Fig. 191) below the surface of water, as in the case of a submerged electric globe, will pass out into the air, following the laws of refraction. All rays from 0, making an angle with the normal equal to the critical angle, will pass out in the surface of the water. These rays are marked 0 C, and constitute a cone whose vertex is at 0. Rays striking the water farther out, and making an angle of incidence greater than the critical angle, would be totally reflected. of the ray S C, which would seem to have come from C' C. The whole water surface outside of the points C would appear lifted to form a cone C' C C C". A boat at a would seem to be at a', a bird at b at &', while a fish at / would be seen at /', by total reflection. they may be studied more at leisure. The shooting-fish of Java is said to project drops of water from its prolonged snout so as to bring down insects flying near the surface. The fish must then be able to allow for the difference between the real and the apparent position of its prey. Look at the diagram and state where an artificial fly on the surface at x would appear to a fish at /; to a fish at O. Could an angler on the bank occupy any position where he would be out of sight of a fish in mid stream f Value of the Critical Angle. — The critical angle is the angle which the ray makes with the normal in any more refracting medium, when the corresponding angle in the less refracting medium becomes 90°. INDEX OF REFRACTION. That is, when r = 90°, i becomes c or the critical angle. This angle is one whose sine is f the radius. Similarly for glass-air, the sine of the critical angle is f , and for glass-water the sine c is f . By construction and measurement by means of a protractor, these angles can be found approximately. They can also be obtained by consulting a table of natural sines : The index of refraction from water to air is 5, and from air to water it is $. The substance containing the lesser angle (water) is said to be more refracting than the substance containing the greater angle. The diamond is a highly refractive stone ; hence its luster. Certain rays falling on the internal surfaces of the facets are, also, totally reflected. The diamond's index of refraction being about ty, while that of glass is only f , we are furnished with a certain test by which to detect imitation A tion. — The glass prism of 90° is frequently used as a reflector. It is more effective than an ordinary mirror, since all the light is reflected. tion to the diagonal face A B. The angle of incidence there is 45°, which is greater than the critical angle 41° 48'. No light, therefore, can pass through the face A B. It is all reflected. The Camera Lucida. — The principle of total reflection is utilized in the Camera Lu'cida, an instrument designed to facilitate the drawing of distant objects. Rays strike the face c d of a totally reflecting prism, inclined at an angle of 22\|°. (See Fig. 193.) They are totally reflected to the surface d «, and thence to the eye pp. As the paper and pencil to be used in the sketch are not visible through the prism, the eye must be so placed that a part of the pupil projects beyond the prism. Half of the pupil thus receives the reflected rays, and the reflected image is seen projected on the paper beneath. There is a mov- The camera lucida is useful, not only for drawing objects, but also for copying. The copy may be reduced to any size by regulating the distance of the original from the prism. You can construct a simple camera lucida by fixing on a stand a piece of plane glass at an angle of 45° to the horizon. An image of surrounding objects will be seen through the glass on a sheet of paper laid on the table. The glass both reflects the image and permits the writing materials to be seen through it, so that an outline may be readily traced. Why is the image in this case inverted ? ings may be made. Velocity of Light in the two Media. — The velocity of light is greater in air than in water ; and, in general, it is greater in the less refracting than in the more refracting medium. The angle i is in the same medium where the velocity is v. Law of Least Time. — If a man were required to travel over uniform ground, from a point B to a point A (see Fig. 194), in the least possible time, his path should be a straight IN DIFFERENT MEDIA, AND THE LAW OF LEAST TIME. line joining the two points. If, however, A is in a meadow, where he can run with a velocity of 8 miles an hour, while B is on plowed ground, where his speed can not exceed 6 miles, the boundary between the two surfaces being li m' m h'9 then his path must be differently chosen. crease in the total distance will more than compensate for the advantage of traveling the greater distance over good ground. The point m should be so chosen that the runner is refracted at the boundary, as light is refracted in passing from one medium to another. Mr. Haughton observed, on the beach near Swansea, some oysterwomen who furnished an illustration of this law. In a course between points situated like A and B, the hard walking was a strip of rough, slippery shingle between the water and a smooth common. They were all refracted at the boundary-line, unconsciously choosing paths which reduced their labor to a minimum. The path is the same, whether the journey be from A to B or from B to A. PROBLEM.— If A h = 2 miles, h' B = 6 miles, and h'h = 2Q miles, find the distance h' m for minimum time. Find the times for the four paths A h B, A m' B, A m B, A h' B. QUESTIONS. — When light strikes a transparent body, is it all reflected ? Instance a familiar example which proves that rays are bent on passing from one medium to another. Explain what is meant by the index of refraction. State the index of refraction for air-water ; for air-glass ; for water-glass. Describe the appearance of a stick partly immersed in water. Show by diagram how points on the stick must appear to change their real positions. Why Describe the appearance of water to one look, ng outward from the shore. How much deeper is water immediately under a bather than it appears to be ? About one third. Is it true that we see the sun before it actually rises ? Why is this f Perhaps you can further explain why objects on either side of a hot stove-pipe seem to have a tremulous motion ; why stars twinkle. What causes a diamond to sparkle V On what principle may imitation stones be detected ? Explain the phenomena of Total Reflection. Illustrate with a glass cube. What is the critical angle ? Describe the appearances from a view-point beneath the water. Give an account of the shooting-fish. Is the velocity of light different in different media ? State an interesting analogy between the refraction of light and the refraction of a runner in passing from smooth to rough ground. second effect will be discussed under the head of Color. Let a b c be a section of a glass prism at right angles to the edges. A ray of light from o, entering the prism at d, is bent toward the normal. Passing on to e, it is bent away from the normal in again entering the air. Both of these effects deviate the ray in the same direction. The object o appears to be at i, in the o h i, which is called the angle of deviation. A liquid or gas can, for the purpose of experiment, be confined in a hollow prism made of glass plates cemented to a triangular frame or box of metal or glass. Glass bottles of this form are in common use. When the sides of a glass prism are parallel, it becomes a plate of glass. At the second face, the ray is restored to its original direction and proceeds in a parallel path. LENSES. Loss of Light by Multiple Reflection. — When a ray of light falls upon a plate of glass, part of the light is reflected, and part enters the glass and is incident upon the second face. At the second point of incidence, the light is again divided, part passing through the surface into the air, in a path parallel to the ray's original direction, the other part being internally reflected. This latter ray strikes the first face, where part passes out into the air, and another part is Lenses are masses of glass, bounded usually by spherical surfaces (see illustration, page 293). Various forms of lenses in use are shown in Fig. 197. The shaded part of 1 the space common to two intersecting spheres. If the center c' of the left hand sphere be supposed to move to the left an infinite distance, the size of the sphere would be so increased that the part which intersects the second sphere would practically become a plane. A lens formed by such an intersection is a, plano-convex lens, and is shown in 2. middle than at the edges. If the two spheres do not quite intersect, the space between their surfaces will have the form of a double concave lens. Such a lens would be bounded by the two spherical surfaces, and a cylinder, whose axis passes through the two centers, as is shown in 4. Moving the center c' to an infinite distance to the left, we form the plano-concave lens shown in 5 ; and, finally, if the center c' is on the right of c, we have the concavo-convex lens shown in 6. The last three lenses are thinner at the center than at the edges. to any point of that face is called the normal at that point. The principal axis of a lens is the line passing through the centers of its two bounding spheres. If the radii of the two spheres are equal, the point on the principal axis, midway between the two faces, is called the optical center. secondary axis. Lenses 1, 2, and 3, of Fig. 197, have the same effect upon light as two prisms with their bases together. They cause parallel rays to converge toward the axis. They increase the convergence of converging rays, or diminish the divergence of diverging rays. Lenses 4, 5, and 6 will diverge rays from the axis. Principal Focus of Converging Lenses. — The double convex lens will serve as a type of converging lenses. The principal focus is the point to which parallel rays are con- the principal focus of the lens. Real and Virtual Foci. — The principal focus of a double convex lens is a real focus. Parallel rays, after passing through the lens, are actually converged there. The principal focus of a double concave lens is a virtual focus. Parallel rays, after passing through the lens, seem to have diverged from that point. If a double convex lens, as an ordinary pocket glass, be held in the sunlight, the image of the sun is formed in midair. It may be rendered visible by smoke or dust in the air, or it may be projected on paper. The virtual image of the sun formed by a double concave lens can not be projected on paper. It has no real existence ; it is an optical illusion. It can be seen at F, if the eye is placed in the divergent beam. Conjugate Foci. — If the rays passing through the double convex lens proceed from a point 0, not infinitely removed, the rays will diverge upon the lens, and will converge to a point I, which is farther away from the lens than the principal focus. If 0 moves away from the lens to an principal focus, I will move away to an infinite distance, or the rays will emerge in a parallel beam. For each position of 0, there will be a definite position of its image I. In all these cases, if the radiant point 0 be placed at the position occupied by the image, the image will appear at the former position of the object. The object and image have changed places, and the light retraces its former path. Points thus related are said to be conjugate foci. radiant point be placed nearer to the lens than the principal focus, the rays will diverge after passing through the lens. The point I, from which they seem to have diverged, will be a virtual focus. The nearer the radiant point 0 is to the principal focus, the farther I will be from the lens. The object and its image are not at conjugate points when the image is virtual. Formation of Images by Lenses. — Let A B represent any object. If rays proceed from the extremities A and B through the optical center, they pass on without refraction. Such rays follow the line of the secondary axis. The image of B will be somewhere on the secondary axis through B. Draw any other ray from B, and find where it intersects the secondary axis through the object in shape and color. It is convenient to select, as the second ray radiating from B, that one which is parallel to the principal axis. This ray passes through the principal focus, F, and thence on until it intersects the secondary axis, in b. Similarly, rays from A, on passing through the lens, will converge upon the secondary axis through A at a. Thus the image will be inverted. the lens until its distance becomes equal to the present distance of the image, a b would recede until its distance equals the present distance of the object. The object and image occupy conjugate foci. The image is always real when the object is outside of the principal focus. Virtual Image. — If the object is nearer the lens than the principal focus, the image will be virtual, magnified, and erect. (See Fig. 205.) The image of each point of the ob- Images by Concave Lenses. — Images formed by concave lenses are virtual, erect, and diminished. They can be seen through the lens, being on the same side of the lens as the object. LAW OP INTENSITY OF LIGHT. 327 cut off by means of a plate with a circular opening, called a diaphragm (di'a-fram). The image formed by the central rays thus becomes more distinct, but it is less bright. Spherical mirrors have the same defect. Light a lamp, and with your reading-glass illustrate the principle explained above. A diaphragm may be made out of a piece of cardboard, and the central rays focused. If the central portion of the lens be covered with a circular piece of paper,- the marginal rays may be focused. Measure the focal distance in each case, and compare the images with that formed by the entire lens. Law of Intensity of Illumination. — The images from lenses are always formed in a fixed position when the position of the object with respect to the lens is once fixed. Moving the screen upon which the image is projected, will throw the image out, of focus. The images formed by a small opening may be projected on a screen at any distance from the opening. Doubling the distance of the screen will double the linear dimensions of the image. The surface covered will, therefore, be four times as large, and since the amount of light streaming through the opening is the same in each case, the brightness of the image in the second position will be one fourth as great as in the first. The same principle applies to images formed by lenses ; they vary in brightness inversely as the squares A J3. light. The same light, if not intercepted at A, goes on to B at a distance of 2 feet. It there illuminates four squares of the same size as the card, and has, therefore, but one fourth of its former intensity. If allowed to proceed to C, 3 feet, it illuminates nine such squares and has but one ninth of its original intensity. QUESTIONS.— Describe a Prism. Name the two effects of prisms on light. Explain the course of a ray of light through a prism. What can you say of the loss of light by repeated reflection ? Define Lenses. Name and describe each kind of lens. What is the center of curvature of a lens ? The normal ? The principal axis ? The secondary axis ? The principal focus ? Distinguish between real and virtual foci. What is the focal length, and by what is it determined ? Explain conjugate foci. How are images formed by lenses ? When are they inverted ? Suppose the object to be nearer a convex lens than the principal focus ; describe the image formed. How can you verify this with your simple pocket microscope or reading-glass ? Describe the image formed by concave lenses. What is Spherical Aberration and what does it cause ? How can you illustrate it ? Demonstrate the law of intensity of illumination. COLOR. Decomposition of Light by Prisms. — If a triangular prism be placed in the path of a slender beam of light (see Fig. 208), instead of a round, white image of the sun, we observe a band of color. The light is refracted, as has been already explained, but it is not all equally refracted. At one extremity of the band, or spectrum, the light is violet ; the angle R P E. The band of color is, in fact, a series of overlapping images of the sun (see page 297). These images can be again superposed by means of a double convex lens, as is shown in Fig. 209. The resulting image is white. spectrum. Prisms of Different Material, as crown-glass, flintglass, quartz, rock-salt, and water, having the same angle, will refract light unequally. If the angles of the prisms are adjusted so that they all deviate the red ray through equal angles, the violet rays will still be deviated through different angles. In other words, the spectra will have different lengths. Flint-glass gives, under these conditions, about twice as long a spectrum as crown-glass. In Fig. 210, F represents a prism of flint-glass, and C one of common glass, whose angles are so adjusted that they give spectra of the same length. When placed as shown in the figure, one will therefore neutralize the dispersive effect of the other, and the emerging beam will be white light. It will, however, have been deviated toward the base of prism C. Chromatic Aberration. — A combination of lenses or prisms in which dispersion into color is neutralized, is said to be achromatic. Objects seen through ordinary lenses are surrounded by a fringe of color, which, like spherical aberration, interferes with definition. This arises from the fact that rays of different colors are refracted to different foci, involving the formation of a number of images partly overlapping one another. The defect is known as chromatic aberration, and is corrected by combining a convex lens of crown-glass with a concave lens of flint-glass. the band are colored, and explain their appearance. A Newton's Disk consists of a circular piece of cardboard, having colored sectors. The sectors may be of tinted paper, pasted on a card, as in A, Fig. 212. If the disk is spun rapidly round, the color impressions blend, and it appears of a grayish- white color, B. (See No. 2, introductory cut, page 293.) proper proportion. In the experiments just described, the colors are combined by the persistence of vision. At any given instant, the image of each sector is formed at a certain point on the retina of the eye. As the sector revolves, its image moves round in a corresponding path upon the retina, returning quickly to its original position. The rapid recurrence of each colored image has the same effect as a simultaneous impression of all. If a colored sector is put on a black disk and the disk revolved, the effect will be that of the color diluted with black, the precise appearance depending upon the relative amounts of colored and blackened surface. will be a mixture of the two tints. Vary the height of G above the papers. At a certain distance the mixture will appear a dull white. If the glass is raised the color will be yellowish, and if depressed it will be bluish. Why1? seen, a white. Remove red from the disk, and the remaining colors will, on rotation, give a bluish green. Match this color by a colored paper, and place it upon the disk with red. Rotate the disk, and the result will be white. In the same way, orange and cyanogen blue, purple and green, will yield a white. In Fig. 214, the colors which are shown opposite one another, when mixed by a Such colors are called Complementary A combination of red and green in different proportions will produce the intermediate colors— orange, yellow, and yellowish green. Prom violet and green, the colors bluish green, cyanogen blue, and ultramarine blue can be obtained ; while violet and red give purple. A mixture of no two colors will produce red, violet, or green. These are therefore called primary colors, while the others are called secondary, as they all can be obtained by mixing the primaries. The eye is not able to distinguish between the white produced by mixing all the colors of the spectrum, and that formed from any two complementary colors, or from the three primary colors. In this regard, the eye has less power of analysis than the ear. When a harmony is rendered, the ear can detect each of the simultaneously sounded notes of every instrument, and the trained ear of one familiar with the music can single out any instrument in the orchestra, and detect an error in the playing. Color of Mixed Pigments.— If the two pigments known as chrome-yellow and Prussian-blue be mixed, the result will be a green pigment ; but the mixture of yellow and blue light will produce white light. Blue and yellow light may be mixed on a screen by means of two magic lanterns, plates of colored glass being used as slides. The experiment is a very striking one, as shown in Fig. 215. send a beam of white light through each. Allow the two beams of light to fall upon a screen. One will appear yellow, and one blue. If the colored beams be passed through a prism, it will be found that the blue beam If the gelatines gave pure yellow and blue lights, the result of their combination, as in Fig. 217, would be darkness, and not green. The yellow gelatine would transmit only yellow light. This would be quenched by the blue gelatine, which would transmit only blue. COLOR OF BODIES. 335 An irregularity, like that shown greatly exaggerated at b m, would disperse the light, leaving a gap, as a c, in the reflection on the wall. Here the white light from the upper surface, from such rays as those marked 1, 2, 3, 4, will be observed. So in all colored bodies, the colored light comes from the interior of the body, where it has been reflected from facets slightly below the surface. The color is due to light aot quenched by the body. When a blue and a -yellow pigment are mixed, green is the only light which penetrates slightly below the eurface, and is reflected out again, unquenched. If the pigments which artists use were all pure colors, a mixture of any two would give black, which would appear grayish on account of the white light reflected from the surface. When light is quenched within a body, it is because the energy of vibration is used in setting the molecules of the body into motion. The body is heated. The Color of Bodies thus depends upon their molecular structure. Different bodies quench different portions of the complex solar light. The unquenched light determines their color. The color of bodies also depends on the light which falls upon them. It contains no red, green, or blue light. In a room illuminated only by this light, the red flowers and green leaves of a geranium or rose look exactly alike, being a dark gray. A stick of red sealing-wax appears dark brown or black. These bodies can not reflect yellow light. In a dark room, all things are black, or without color. The clouds sometimes quench unusual portions of the sunlight, and all the hues of the landscape are changed. During storms, these changes often take place rapidly. The morning and evening sunlight contains less of the violet end of the spectrum than the noon sunlight, as the light travels a longer distance in air, in which the yellow and red rays are less affected than the others. The Color-Sense and Color-Blindness. — Finally, the color of bodies depends upon the eyes of the observer. We can not describe our color sensations to one another. We are taught that the grass is green, the rose red ; but it is probable that no two persons see colors alike, although they apply the same names to them. There are, in fact, many who can not distinguish a red or a scarlet from a drab or brown. To such persons, a pink rose has the same appearance as it does to the normal eye when seen by moonlight. They are said to be color-blind to red. Color-blindness is the result of some disease or congenital defect in the nerves of the eye ; it does not necessarily interfere with keenness of vision. Blindness for all colors is rare. A patient totally colorblind would be unable to distinguish between the red and white stripes in our flag, or the blue background and its white stars. without moving the eyes, withdraw the black cloth. The upper portion of the paper will appear a dull gray, in comparison with the section just uncovered, because that part of the retina upon which the brighter image was formed has become less sensitive. Ordinarily, we do not notice such changes, as they go on gradually, and we have no means of simultaneous comparison. The white paper may be replaced by red. This will look dull after a minute of exposure to the eye, while the freshly uncovered red will appear strong, because its image falls upon an unfatigued part of the retina. When the eye is fatigued for red, all other compound colors will, until the eye recovers, appear as if red had been stricken out of them. White will appear greenish, green appear intensified. MUTUAL EFFECT OF COLORS. 337 EXPERIMENTS. — Look at a strongly illuminated red on a black ground ; then turn the eyes to a white wall. You will observe an after-image of the red spot, which will appear green. If the eyes be directed to a green paper, instead of the white wall, the after-image will appear a more intense green. Look at a bright object, like a white cloud, through a green glass, with one eye, and through a red glass with the other. After a time, transfer both eyes to one glass, and open and close them alternately. Look at objects through a red glass, with one eye, then through a green glass with the other; then look through both simultaneously. In which case do objects seem to have most nearly their natural colors ? fied with work done when their eyes were fatigued. Mutual Effect of Colors. — Paste one circular piece of green paper on the center of a gray card-board, and another on the center of a red one. The green surrounded by red will seem much stronger. The red also appears stronger than it would if the green were absent. Fix the eye upon the center of the green disk surrounded by red. At the same time, notice the colors at the boundary between the red and the green. Both colors seem stronger there than at some distance away. The fatiguing effect for red or green extends beyond the geometrical boundary of the images on the retina, and hence each color is intensified by the juxtaposition of the other. QUESTIONS.— Explain the decomposition of white light by a prism. What kind of light is most refracted ? Prove that white light is a mixture of all colors. Explain what is meant by chromatic aberration, and show how it is corrected. How may the spectrum colo'rs be combined by a Newton's disk ? Account for the persistence of vision in all such cases. How may colors be- mixed by reflection ? By the use of two lanterns ? By gelatine sheets ? Why do we not obtain the same results by mixing colored lights as by mixing pigments ? What are complementary colors ? On what does the color of bodies primarily depend ? Follow the course of a ray of white light falling on a piece of colored glass. Why is the color of a body determined by light reflected from the interior ? When light is quenched within a body, is heat generated ? Why ? How far is the color of bodies dependent upon the character of the light in which they are seen ? Why is a violet blue ? A calla-lily, white ? Why are sunsets characterized by red and yellow tints ? When is a substance black ? What is white ? What is black ? Is either a color ? Which reflects the most light ? The most heat ? Why are whites and straw-colors seasonable in summer ? Dark-colored fabrics in winter ? THE SPECTROSCOPE AND SPECTRUM ANALYSIS. The Spectroscope is an instrument used for the analysis of light. It consists of one or more prisms for the production of the spectrum, and a telescope for examining it. The light is admitted to the prism through a narrow slit, S, in the end of the tube A (see Fig. 219), and then through a lens at the opposite end of this tube. The principal focus of the lens is at the slit. slit is thus used. The light has been deviated through the angle b a e, which is measured by means of a divided circle on the bed-plate, B'. The telescope swings round the center a, and is first set in the line a b, being focused on the slit PRINCIPLE OF THE SPECTROSCOPE. dispersion of the light. Entering the slit in tube A, the width of which can be regulated by a screw, the light is bent round the train of prisms, and thrown back into the telescope B, being almost reversed in direction. stance, if the yellow light of sodium vapor be observed, the spectrum consists only of a slender beam of yellow light. Not only is that part of the spectrum corresponding to red, orange, green, blue, and violet, wholly wanting, but the greater part of the yellow seen in a continuous spectrum of a white-hot solid is also blank. The yellow light of glowing sodium vapor is thus a very definite kind of yellow. By means of each of these beams, a sharp image of the slit is observed, the images being separated by a dark space. The lower part of Fig. 223 shows these two bright lines. They are also indicated at I), Fig. 224. the glowing vapor, when passed through the slit of the spectroscope, shows a spectrum composed of hundreds of slender beams from red to violet, all separated by dark spaces. By means of each of these beams, a narrow image of the slit is seen, appearing as a bright line. Every substance, when in a condition of glowing vapor, gives a bright-line spectrum on a dark background. As these spectra differ in the number and position of their lines, we are enabled to identify series of overlapping images of the slit. The Solar Spectrum. — When sunlight is examined by a spectroscope, a band of color is seen ; but when the telescope is focused on the slit, the spectrum appears crossed by hundreds of dark lines, as shown in the upper part of Fig. 224. Two of these dark lines are in the yellow, exactly where the two sodium lines occur. They are shown at D in Fig. 224, and in the upper part of Fig. 223. Thus our sunlight appears to be lacking in the kind of light which glowing sodium vapor emits. So, also, the bright iron lines have each a representative line in the solar spectrum ; but they are dark lines, suggesting that the light which glowing iron vapor emits is lacking in our sunlight. These two spectra can be produced at the same time. One shows a band of color with dark lines ; that of the iron spectrum. The Dark Lines. — We might at first think that the apparent lack of sodium light in the sunlight shows the absence of sodium in the sun. This conclusion would be hasty and incorrect. strong. The Bunsen flame may be replaced by a loose bunch of candle-wick, or old muslin torn into strips, moistened first with brine, then with alcohol, and ignited. If the sunlight be cut off, the bright line of sodium will be observed; if the sunlight be admitted, this line will become dark. Now, if the sodium flame be alternately placed before the slit and removed, it will be found that the dark line is made darker by interposing the yellow sodium flame. A cloud passing over the sun may dim the brightness of the solar spectrum. The dark sodium line will then become bright, if the sodium flame be kept before the slit. It is thus proved that the dark lines of the solar spectrum are really bright. They appear dark by contrast with the brighter adjacent portions of the spectrum. give a continuous spectrum, without either bright or dark lines. But suppose this glowing mass to be surrounded by an atmosphere containing cooler (although brilliant) sodium vapor. This vapor would absorb light of the same kind as it emits, and hence a dark line would be left in the spectrum. As the previous experiment shows, we can even increase this absorption, by causing the sun's light to pass through more sodium vapor placed in front of the spectroscope slit. mosphere of the sun and stars. A Similar Case of Absorption. — Sweep a violin string with a bow, and at the same time slide the finger along the string, changing the note from the fundamental to the highest note of which the string is capable. An infinite number of notes will have been successively produced. If all these notes were simultaneously produced, we should have a complex sound similar to the complex light of a white-hot body, having color ranging from red to violet. Imagine this complex sound to proceed along a hall-way across which are stretched a multitude of wires, all attuned in unison to some definite pitch. The sound-waves in unison with these wires would largely exhaust themselves in setting the wires in motion, while the waves not in unison would pass through unchecked. The complex sound after passing through the wires would be lacking in precisely the sound which the wires produce if they are set in motion. If an adjustable resonator were used to analyze this complex sound (see page 404), it would be silent when adjusted to the pitch of the absorbing wires, and would give a loud response if its length were made greater or less. more strongly heated. QUESTIONS.— Explain the principle of the spectroscope. Describe the four-prism spectroscope. Can artificial light be diffused by a prism ? Is the spectrum formed always the same as that of the sun ? Illustrate in the case of sodium vapor ; in the case of the glowing vapor of iron. How may substances be identified by means of the spectroscope ? Describe the Solar Spectrum. Account for the dark lines. Why would it be incorrect to argue that the apparent absence of the characteristic light of any element in the sunlight proves the absence of that element in the sun ? Cite an experiment in point. Are the dark lines really dark ? How may they be the result of absorption of light ? State a similar case of absorption of sound. Of what does the spectroscope show the heavenly bodies to be composed ? The Solar Kay exerts different effects upon different organs. Falling upon the retina of the eye, it produces the sensation of light, and different parts of the solar spectrum excite sensations of different colors. Its effect upon the sensory nerves of the body is to cause the sensation of heat. These nerves, however, can not distinguish between red greater or less energy. Invisible Solar Bays. — In like manner, by far the greater part of the solar spectrum is imperceptible to the eye. The spectrum extends somewhat beyond the violet and very far beyond the red. The existence of the invisible parts of the spectrum — the ultra-violet and infra-red. — is proved by other means than the effect upon the eye. For example, the salts of silver will blacken in the dark rays beyond the violet, and delicate instruments for indicating heat show marked heat effects for several spectrum lengths below the red. The instrument best adapted for these heat measurements is a slender strip of platinum, which is placed transversely across the spectrum and can be moved from one end to the other. By means of proper instruments, the electrical resistance of this platinum strip is measured. This resistance increases as the strip is warmed, and diminishes as it is cooled. Every dark line in the visible spectrum is found to be a cold line. When the instrument is moved far out into the ultra-red, the temperature falls as it passes through cold lines and bands, and rises when it encounters the warmer radiations that bound these on either side, all being wholly invisible. Solar Light is essential to Vegetable Life ; plants deprived of it wither and die. It is believed that the energy exhibited in the growth of plants is directly traceable to the green coloring-matter which occurs as grains in their cells, and which by absorbing rays of light transforms the energy residing in the molecules. The infra-red or heat rays are also an important factor in this process ; but germination is furthered principally by the ultra-violet rays, which, by a provision of Nature, are in excess in the spring. Chemical Effect of Sunlight. — If the dampers of a piano are raised and a given note sung, the string in unison will respond. No other string will do so. Persons with powerful voices have been known to shatter a glass vessel by singing into it the note which it would yield if matic lens mounted in a wooden struck. Similarly, light-waves, beating upon certain substances, throw the molecules into a vibration sufficiently violent to shake them asunder. This is called a chemical change, and explains the fading of colors in sunlight. Silver compounds are particularly sensitive to decomposition by the blue and violet rays. Photography depends upon this chemical action of light, an image formed by lenses being received on a sensitive film of iodide and bromide of silver exposed in a camera obscura (dark chamber). The silver salts are chemically affected by the strong lights and shadows of the picture, so that the latter may be developed by a second operation. cusing, the lens is usually movable in the brass tube, and the camera is provided with a rubber or cloth bellows by means of which the ground-glass plate may be pushed backward and forward. When a focus is obtained, the ground-glass NOTE.— The chemistry of photography is fully explained in the manuals of instruction issued by all reputable dealers in photographic materials. It ie no longer difficult, to become an expert photographer. The Scovill & Adams Company, of New York, furnishes outfits at prices within the reach of all ; and the young pupil, equipped with a camera and dry plates, can intelligently investigate both interesting phenomena of light and the chemical processes associated with one of the most fascinating of arts. glass plate is slipped into its place. When object and image are equally distant from the lens, they are of the same size. If the object is brought nearer, the image is enlarged, and in photographing from the microscopic field it is greatly exaggerated. Features invisible to the naked eye are thus magnified and photographed in the Photo-Micrographic Camera. Microscopic photographs, or representations of large objects greatly reduced, are also made on glass of a size so small as to be visible only through a powerful magnifier. Small lenses of short focal length are employed to form images of microscopic minuteness. The contents of 10,000 volumes might in this way be so materially reduced as to be contained in a single drawer, but the photographs would have to be read through a microscope. Pages have been concentrated on a surface, one inch square, and during the last siege of Paris trained pigeons carried to and from the city long dispatches thus reduced. In good cameras, spherical and chromatic aberration are corrected by combining crown and flint glass in the lenses, and by the use of diaphragms. The principle of the camera obscura is utilized by the draughtsman, A mirror is employed to reflect the landscape to a lens mounted in the top of a suitable camera ; the rays are thus brought to a focus on a sheet of paper, forming a distinct image which can be readily traced with a pencil. The camera is large enough to admit the upper part of the draughtsman's person, a dark curtain excluding all light except what enters from above. A small tent supported by a tripod is sometimes used, enabling the artist to sit at a table within. QUESTIONS.— Illustrate the different effects of the solar ray on the retina ; on the nerves of the body ; on germination and the growth of plants. Can the sensory nerves distinguish between red heat rays and violet heat rays ? What parts of the spectrum are invisible to the eye ? Describe an instrument adapted to measuring heat in the spectrum. How can you prove the existence of the invisible solar rays ? How may a glass vessel be shattered by sound vibrations ? Similarly, describe the principle of chemical change by light ; the fading of colors. What is the action of light on silver salts ? Describe minutely the photographer's Camera, and the process of Photographing. When are object and image of the same size here ? Explain the purpose of the Photo-micrographic Camera : the uses of microscopic photography. Describe the draughtsman's camera. The Human Eye is a camera. Its outer envelope is quite fibrous and rigid, serving as a protection for the refracting structures within. It is called the white of the eye, or the sclerotic coat (see Fig. 226), gives attachment to the pended in its capsule by the suspensory ligament. The glassy, jelly-like vitreous humor fills the posterior cavity. These structures serve to form a real and inverted image of external objects on a delicate nervous membrane called the retina, which lines the choroid coat at the back of the eye. The nerve-fibers of the retina gather into the optic nerve, the medium of communication with the brain. Spherical aberration is in part avoided in the eye by the curvature of the retina, and through the cutting off of marginal rays by a movable diaphram called the iris. It is the color of this diaphram which determines the color of the eye. The aperture in the center is called the pupil. The iris automatically regulates the size of the pupil, and hence the amount of light admitted to the eye-ball. The Eyes Move through a considerable angle in their sockets in order that they may be directed upon any object. Accurate seeing is done only by a minute spot on the retina, called the yellow spot. ACCOMMODATION. 347 Fix the eye upon the middle of a line of this page and you will find yourself unable to read the whole line without moving the eyes. You have the power to direct the eye from the bottom to the top of a letter, the object of the act being merely to bring the image of the point to be observed upon the sensitive spot. When the sky is clear, the planet Venus is usually visible at midday. It is, however, very difficult to find the planet, although it is distinctly seen when found. This shows that the sensitive spot is extremely small. Accommodation. — The eye, like the camera, requires to be focused for objects of varying distance. This is accomplished mainly by a change in the curvature of the front of the lens, accom- to see distinctly both near and distant objects. Looking at a near object requires a fatiguing effort of the ciliary muscles (see Fig. 226), which relax the suspensory ligament, allowing the elastic lens to become more convex. The eye is rested by fixing it on a distant object. Single Vision with Two Eyes. — The axis of the eye is a line passing through the center of the pupil and the sensitive spot. When we look at anything, the axes of the two eyes converge upon it and it is seen as a single object. Two images are formed, but they impress corresponding points of the two retinae, and hence the notion of a single object is conveyed. Fix the eyes on a door-knob, or any small object, and gently push one eyeball aside with the finger. The images are thus made to fall on non-corresponding points of the retinae, and the object is seen double. that of the arrow C D is c E d. A given object looks large or small according to the visual angle under which it is seen. If we measure the apparent lengths of the equal arrows by an interposed rod, the nearer one will measure a I, and the farther one about half as much, c d. seconds, an object becomes invisible. Estimation of the Real Magnitude and Distance of Bodies. — A person born blind and obtaining his sight after having been educated as a blind man, can not recognize bodies by the newly acquired sense, but continues to do so by touch. He handles objects again and again, and memorizes their names in connection with their colors and forms, knowledge of colors being all that the eye primarily gives. Everything appears to him as if painted on a screen, so that notions of distance and magnitude have to be acquired by slow experience, as in the case of every child. INVERSION OF THE IMAGE. comparison ; but when we are placed amid unfamiliar surroundings, we make ludicrous mistakes. In a wild, mountainous country, we are likely to mistake a mountain covered with enormous trees, twenty miles away, for a hill grown with bushes within two miles. In such a landscape, the presence of a man or a house at once enables us to form more correct estimates. We can judge of the distance of a familiar object by its apparent size, and we can estimate the size of an unfamiliar object on familiar ground ; but where real magnitudes and distances are unknown, the apparent size affords no information regarding either. Hence, on the top of Mount Washington, or in the parks of Colorado, a visitor from the seaboard is often deceived by the apparent nearness of distant objects in the clear and rarefied air. Why we see Objects Erect. — The image on the retina is inverted, and yet we see and localize objects as they are. The reason of this is -that we do not see the retinal image in the same sense that we see external things. In fact, the mere image on the retina affords no information to one who has not been trained to interpret its meaning by touch. Engineers who use a telescope in which everything is seen inverted, soon learn to look through the telescope at the rodman and direct his movements without noticing that they see him inverted, and that they direct him to move in an opposite direction from that which is apparently right. When thus trained, an engineer, using a telescope in which everything is seen erect in its real position, would continually make mistakes. While using such instruments alternately, an observer is frequently compelled to make a deliberate examination to determine whether the image in the field is erect or inverted. in focus, horizontal lines are out of focus. Fig. 229 is a diagram used for proving this error. When held at a distance, the vertical sectors are often sharply defined, while the horizontal ones are blurred and indistinct. This fault exists to some extent ia all eyes. When very marked, it is called Astigmatism (implying that the rays do not converge to a point). Astigmatism is corrected by means of spectacles of cylindrical curvature, either convex or concave. Irradiation. — A luminous body looks larger than a dark one of the same size and shape. A red-hot wire and the hot carbon filament of an incandescent lamp appear very much larger than when cold, although the real change white, although both are exactly the same size. These experiments show that, in bright images, the retinal effects extend beyond the geometrical boundaries of the images. The same results are noticeable in photography, and the effect of complementary colors upon each other is similar. It is in accordance with this principle of irradiation, or apparent enlargement of brilliant objects, that persons of taste adapt the color of their clothing to their size and figure. and vice versa. Long and Short Sight. — Some eyes are elongated along the axis, so that the image is formed in front of the retina unless the object is held very near. Such eyes are said to be near-sighted. They are corrected by using diverging glasses. Other eyes form the image back of the retina unless the object is held off at an inconvenient distance, in which case it often becomes indistinct. The correction is here made by convex glasses, as in retina, are represented by heavy lines. In the short-sighted eye, where the axis is too long, a dotted line marks the contour ; an indistinct image is formed at B, beyond the focus. The far-sighted eye, with too short an axis, is indicated in the diagram by the hair line. Other defects in the eye are noticed only by those who engage in unusual work. In many optical researches, where divergent light enters the eye, the field is seen full of fugitive shadows cast by particles floating in the liquids of the eye. They can usually be seen to a limited extent when one lies upon the back and looks at the sky, for when the body is erect they rise to the upper part of the ball, out of the line of vision. Chromatic Aberration is another fault which the eye has in common with all lenses. Since violet light is more refracted than red light, the principal focus for violet rays diverge into a circle upon it. piece of blue glass. The glass will cut off yellow and green light, admitting blue and some red. You will see the flame red, surrounded by a blue halo. If you now use concave spectacles of proper curvature, you will throw the blue focus back upon the retina ; the red focus will then be behind the retina, and you will see a blue flame surrounded by a red halo. The Blind Spot. — The spot where the optic nerve enters the eye, is blind. To prove this, close the right eye, and, holding the book about six inches from the face, look with the left at the dot below. If properly adjusted, the cross will be invisible. Move the book nearer to, or farther from, the eye, and it will reappear. A large dot and cross may be placed on the blackboard, the size being greater in proportion to the distance. When the cross disappears, on approaching or receding, its image falls on the blind spot. If the left eye is closed, the right must be directed to the cross. The image of a lamp-globe or the full moon may be shut out in this manner. The blind spot is large enough to cause the disappearance of seven full moons placed side by side. The experiments described above prove that the optic nerve is blind, and that the true function of the retina is the mysterious conversion of vibrations of ether into the proper excitants of this nerve, whose fibers communicate to the brain sensations of light and color. Care of the Eye. — The eye is admirably adapted to the wants of a pastoral or savage people, not even failing them in old age ; but the increasing demands of a civilized life bring it into use under conditions which it is not so completely designed to satisfy. Injury to the eye may be prevented and its usefulness prolonged by observing the following precautions : — Do not use the Eyes— 1. In insufficient light, as in deepening twilight, or when the sun is obscured by a rain-cloud. 2. In excessive light, as the glare of the sun or of an electric arc. 3. In unsteady light, as that of a flickering gas-jet — the effect of persistent reading in a moving carriage or railway-train is in the end equally pernicious. 4. In hot light, as that of powerful kerosene burners, which over-congests the retina. 5. Do not sleep with a light in the room, as the eyelids are semi-transparent, and both retina and brain, which should have rest, are continuously irritated. 6. Avoid sudden and intense changes of light, as the pupil responds slowly. 7. Avoid light that enters the eye directly. While working, use an opaque QUESTIONS.— Prove that the human eye is practically a camera. Describe minutely its anatomy ; its several coats, its lens, its humors, the office of the iris. How can you prove there is a spot of distinct vision ? How is the eye accommodated to objects of varying distance ? Explain the principle of single vision with two eyes ; of the determination of size and distance. On what does apparent magnitude depend ? Why do the sun and the moon appear larger when near the horizon ? How long is a child in acquiring an approximately correct appreciation of distance and magnitude ? About three years. Why do we see objects erect ? What is astigmatism ? Illustrate irradiation. Explain long and short sight. When an image is formed in the vitreous humor instead of on the retina, what kind of glasses are required ? Why do old persons hold objects at a distance in order to see them distinctly ? What kind of eyes require double convex spectacles ? Can you give a reason for not forming the habit of reading while lying on the back ? Explain chromatic aberration in the eye. What is the blind spot ? Describe experiments that prove its existence. State precisely the office of the optic nerve and of the retina. What precautions should be observed by persons desirous of preserving their eye-sight ? Why does a sudden entrance into bright light give pain to the eye for a time ? Why is it injurious to the eye to sleep with a lighted lamp in the room ? Is it true that cats and owls can see in the entire absence of light ? Will a diamond glisten or a cat's eyes shine in the dark ? Why is the pupil of every eye black ? of oxygen and hydrogen gas under pressure in the cylinders 0 and H. The condensing lenses, X, serve to converge the rays upon it, and a focusing lens, D, produces a real, inverted, and enlarged image I upon a screen (see Fig. 233). The position of the focusing lens D can be varied so as to bring the image on the screen. The farther the screen is away, the nearer the lens must be moved up toward the slide. If the slide be brought up to the principal focus, the image will be infinitely distant. In the camera, the picture of the external object is formed on the slide. In the stereopticon, the slide is used to reproduce a representation of the original object. The image in the one instrument corresponds to the object in the other. The simplest form of the stereopticon is the ordinary magic lantern, which the pupil may easily construct as follows : Make a tube for the focusing lens by winding paper round a broomstick or curtain -pole of the required diameter, applying mucilage at every turn. Set this when dry in a cigar-box furnished with a tin chimney. Use a common burningglass for the condenser, with a tin reflector behind it and a kerosene-lamp for illumination. If photography is an.accomplishment of the pupil, he can supply original illustrations for his magic lantern without limit should he further master the process of printing positive transparencies from his glass negatives. (Precise instructions for making Fig. 235 the object a is placed just outside the principal focus of a lens or combination of lenses, 0, and a real magnified and inverted image, b c, is formed. This image is then itself magnified at B C THE TELESCOPE. 355 by means of a simple microscope E, called the eye-lens. The latter is usually mounted in a sliding tube, so that it can be properly placed with respect to the image. The lens and tube together constitute the eye-piece. If the magnifying power of 0 is fifty, and that of E four, the image seen will be two hundred times the size of life. As in the case of the photo-micrographic camera, the microscope may be combined with the stereopticon, and illustrations of minute objects thrown upon a screen for the instruction of an audience. The electric light is now generally used for illumination, and the instrument is therefore known as the photo-electric microscope. Astronomical Telescope. — The telescope produces a magnified image of- an object which appears small because it is far away. The instrument consists of an object-glass 0 (Fig. 236), which forms a real, inverted, and diminished image, a #, of the distant object A B. This image is viewed by means of a simple microscope E, as in the case of the compound microscope, and is thus magnified at C D. In the terrestrial telescope, or field-glass, two additional lenses are introduced between the real image and the eye-lens, with the effect of correcting the inversion and showing the object in its natural position. NOTE.— A serviceable compound microscope may be obtained of Messrs. Queen & Co. at the extremely moderate price of five dollars. Provided with two object-lenses, which, in connection with the eye-piece, magnify several thousand times, it is capable of affording endless entertainment to the young investigator interested in the study of animal and plant life. Much may be learned from the use of a pocket magnifier, which is a simple microscope. world. The tube is fifty-seven feet in length, or nearly as long as the shaft of the New York obelisk. The two glasses which form the objective (a yard in diameter) cost over $50,000. The telescope is driven by a clock inside the pier, which causes it to move so as to follow any star upon which it is directed. The rods seen along the tube are intended to clamp the telescope on its axes, and to move it when it is not quite in position. The circles are also read by means of long microscopes. All these fittings are thus accessible to the observer when standing at the eye-lens. lowing simple apparatus : In Fig. 238, S represents a screen of cardboard, through which a cross, with arms about half an inch long, has been cut. This cross is illuminated by a gas-jet L. 0 is a lens (a large pocket-lens will answer) which is placed eight or ten feet from S, and produces an image of the luminous cross upon a screen S'. Mark the dimensions of the image in pencil, and cut it through the card. E is a lens so placed that the card S' is distinctly seen through it. Now remove S' and look through the two lenses at the card S. This arrangement constitutes a telescope. Next let the flame and the eye-lens E change places. Focus the eye-lens on S. The image of the luminous cross in S' is now represented by the cross in S. Remove S and look at the screen S'. This arrangement is a microscope. short compared with that of the telescope objective. Magnifying Power. — As seen through the telescope or microscope, an object appears a certain number of times as large as when seen from the same point with the unaided eye. This number is called the magnifying power of the instrument. In Fig. 239, c d represents the image of the object A B. If c d is projected to the same distance as the object, its length would be c' d'. Hence the magnifying eye. Suppose A B to be a card pinned against a wall. An assistant may then mark the points c' and d with a pencil, as directed by the observer at the telescope. A B and c' d are then measured The Stereoscope. — The views used in the common stereoscope are photographs taken from slightly different positions. The view on the left side of the card represents If these figures are observed, with the eyes focused on a distant object, each one will be seen double. The two inside images can be superposed, and will then appear in relief like a solid standing up from the paper. This effect is more easily realized by holding a card or paper between the eyes and between the two pictures, so that the right eye can see only the right picture, and the left eye the left picture. appearance. The two pictures are represented by P and P' in Fig. 241. The diaphragm or partition D prevents the right eye from seeing the left picture, and vice versa. The half lenses L and L' refract the light coming from age with the unaided eyes. Should the two diagrams shown in Fig. 240 be copied on cards, the effect in the stereoscope will be very striking. If the two pictures exchange positions, how will the combined image appear 1? QUESTIONS.— Describe the Stereopticon. Compare it with the camera. How may a simple lantern be constructed ? What should be used as slides ? Explain the difference between a simple and a compound Microscope ; between the images respectively formed by each. What is the Photo-electric Microscope ? Describe the Astronomical Telescope and the image formed in the tube. What is the character of the image in the ordinary spy-glass ? How is the change effected ? What can you say of the telescope at Lick Observatory ? Illustrate the relation between microscope and telescope. How is the magnifying power of an instrument determined ? Explain the principle of the Stereoscope. PHOTOMETRY AND POLARIZATION OF LIGHT. Photom'etry (light -measuring). — As thermometers are used for measuring heat, so there are instruments by which the intensity of light may be estimated. graduated bar. The paper screen has a central spot saturated with paraffine. One side of the screen may be illuminated by two standard candles, and the other side by a gas-flame or electric lamp. When the screen is so placed that the two sides are equally illuminated, the paraffine spot is invisible. When one side is more strongly illuminated, the spot appears dark on that side and light on the other. If a standard candle is lighted at each end, the screen must be placed midway of the bar to render the paraffine disk invisible. If 4 or 9 candles are placed at L' and one at L, the distance L' B must be two or three times the distance L B to insure the same effect. The candle-power of the two lights is directly proportional to the square of the distances from the screen. The photometer should be used in a dark room having blackened walls. The room may be made of heavy paper tacked on a frame. The sliding box may easily be extemporized from a cigar-box, but the paraffine disk and sperm-candles should be ordered of a dealer in physical instruments. The bar is usually 100 inches long and may be graduated to inches. These bars are generally graduated in candle-power direct. If the disk stands at 64 when the illumination is equal, the one farthest from the disk. In order that both sides of the disk may be seen at once, two strips of mirror, m' and m" (Fig. 243), are placed in a vertical position in the back of the box, so that the eyes at E' and E" will see the two images of the luminous spot S at S' and S". In precise work, it is customary to weigh the candles before and after the test, for the purpose of determining the amount of sperm burned in a given time. Two candles should lose 40 grains in 10 minutes. If they lose 39, the two candles are f-§- of two standard candles. If the disk stands on the average 80 inches from the electric lamp or 20 from the candles, while the two candles burn 39 grains of sperm in 10 minutes, the candle-power of the lamp would be — Polarization by Reflection. — If the direct light of the sun be received upon a plate of polished black glass, it can be reflected in any direction upon the walls of a room. The character of light thus reflected is radically changed. In Fig. 244, light is represented striking the lower mirror, and reflected upon a second mirror above. The mirrors admit of being turned on their horizontal axes. So long as these axes are parallel, light will be reflected, as shown in Fig. 244. Turn the upper mirror around a vertical axis through an angle of 90°, so that the axes upon which the mirrors are mounted are crossed, as shown in Fig. 245. When the two mirrors are set so that the light on each is incident at an angle of 54° 35', no light will be reflected from the second mirror ; a black spot will appear in the center of the field of view. If the mirrors be kept at this angle, and the upper one revolved about a vertical axis, the light will grow stronger until the mirror has turned 90°. Then it begins to grow feebler until the mirror has turned another 90°, when it is again wholly extinguished. Light which behaves in this manner is said to be plane According to the accepted undulatory theory of light, an ordinary ray contains vibrations in many planes ; but a polarized ray vibrates in a single plane. The unaided eye fails to distinguish between them. In the apparatus just described, the lower mirror is called the polarizer, the upper the analyzer ; the former produces polarization, the latter makes it evident. Light is also polarized by reflection from water. From the amalgam of an ordinary mirror the reflected beam acts like the direct sunbeam, as far as reflection from a glass plate is concerned. It has, however, been affected in a manner that the student may study in more advanced works, under the head of circular polarization. Reflected light from some bodies, like the metals, can not be wholly quenched by a second reflection from glass. The brightness of the beam passes through a minimum, instead of becoming zero. Polarization by Double Refraction. — If a strong beam of light be directed through a slit in a cardboard, in front of which is a focusing lens, an image of the slit will be projected upon the screen (see Fig. 246). Interpose a polished rhombohedron of calcite (Iceland-spar) between the slit and lens. Two images of the slit will at once appear. By looking into the face from which the light emerges, it will be observed that the beam has separated into two beams of light, each of which gives an image of the slit. That these beams separate, is clearly evidence that one of them has been refracted more than the other. By reflecting these beams from a mirror of black glass, it will be found that they are polarized at right angles to each other. If the mirror is placed at the proper angle, one of these rays will be reflected at its maximum of brightness, and the other will be extinguished at the mirror. Turn the mirror 90° around the rays as an axis ; the ray which had been extinguished will now be reflected, and vice versa. For intermediate positions, both images of the slit will be seen upon the walls of the room, and for the middle position they will be of equal brightness. of calcite, which has been sawed through from one obtuse angle to the opposite, as along the diagonal plane a c b d, in Fig. 248. These surfaces, being polished, are cemented together with Canada balsam. The ray of common light S I, on entering the prism, is refracted into two rays. One strikes the balsam surface at an angle greater than the critical angle, and is reflected out of the side of the crystal as o 0. The instrument thus furnishes a single beam of plane polarized light e E. It is more generally used than a mir- If the transmitted beam is sent through a second prism in a similar position, it will be again transmitted. Turning either prism through 90° renders the field dark. The second prism will cut off the light which the first transmitted. Place a common window-glass over a printed page, in front of a window, and step back until the light reflected from the glass prevents you from seeing the print below. This light is polarized, and will be extinguished by a crossed Nicol. The print will then become visible. In the same way the minimum brightness. Observe the sky in a similar manner. Beautiful colors are produced by the action of polarized light. If a thin plate of mica or sel'enite (moonstone) be placed between the polarizer and the analyzer, the field will be tinted, the color depending on the thickness of the plate. A section of calcite cut perpendicular to the axis of the crystal, when viewed by divergent polarized light, exhibits THE POLAKISCOPE. brilliant colored rings with a cross which is black or white, according to the position of the analyzer. These rings may be seen with the tourmaline polariscope, p. 366. selenite or mica sheet being interposed between them. All fine microscopes are now provided with a polarizing set, consisting of two Nicol's prisms, for the delicate structures of many objects can be studied only under polarized light. A Polariscope may be improvised as follows : Place a plate of black glass or a piece of window-pane, G, on a base-board, which also supports a Nicol's prism at P (Fig. plates are alike, and either may be used as an analyzer. Applications of Polarized Light. — The Saccharimeter. — The polarization of light is used in measuring the strength of sugar solutions. In Fig. 252, m is a polarizing mirror which reflects abeam of polarized monochromatic light through a Nicol's prism, a, serving as the analyzer. The Nicol is so placed that the field is dark. If a tube, d, filled When cane-sugar is examined, the analyzer must be turned to the right in order to produce a dark field ; but, when a solution of glucose is examined, the rotation must be in the opposite direction. The mirror m may be replaced by a Nicol polarizer. THE RAINBOW. 367 The principle of polarization is further applied in examining into the nature of crystals, in difficult chemical analyses, and in determining whether light from the heavenly bodies is reflected from planets and moons, or emitted by suns. The corona of the sun has been photographed during eclipses by light polarized in many planes, and thus has been proved to shine by reflected light. QUESTIONS. — What is Photometry ? Describe the Bunsen photometer. State what you understand by polarized light. Show how light may be polarized by reflection. Can the eye distinguish between polarized and ordinary light ? In a polarizing apparatus, distinguish the polarizer from the analyzer. Explain the phenomenon of double refraction. Illustrate with a piece of Icelandspar. What is a Nicol's prism ? How is it made ? State how it is used ; how it may render objects below the surface of water visible ; how it may produce colors. Having a Nicol's prism, can you design a polariscope ? Describe the tourmaline polariscope. Explain some applications of polarized light. How is it of use to the microscopist ? To the chemist ? To the astronomer ? The Rainbow is produced by sunlight passing through drops of water, which act as prisms. It is composed of the seven prismatic colors. There are sometimes two concentric bows. The inner or primary bow shows the spectrum colors in regular order, the red being outermost. The secondary bow shows the colors in reverse order, the red being innermost. The center of the bows is determined by a line passing through the center of the sun and the eye of the observer. This line is called the axis of the bow. Conditions of Visibility of the Rainbow. — The observer must stand with his back to the sun, and the drops which produce the bow must be in front of him. the part of the bow below the horizon is not usually visible in a level region, because there is not a sufficient number of drops between the eye and the immediate foreground to produce an appreciable effect. ray of sunlight, S #, falling on the upper part of the drop, will be in part reflected ; but some of the light will enter the drop. Of this light, incident upon the inside of the surface at n9 part will pass out again into the air. escapes into the air proceeds to the eye at E. If this drop is so situated as to send red light to the eye, then, since they are more refracted, violet and in fact all other colors will be thrown above the eye, as in a! v, representing the violet ray. The drops which send violet to the PROBLEMS IN LIGHT. 369 visible at that altitude. They are supposed to send violet light to the eye after one reflection, the rays being marked v p. The rays v s are the violet rays of the secondary bow. The drops are represented at different distances from the eye. If the ground were at G' G', then only half of the bows would be visible, unless the region immediately around the eye were filled with a dense spray, when a complete circular rainbow of the same angular magnitude might be seen. The real diameter of a bow is indefinite, as some of the drops producing it may be only ten feet from the eye, while another drop an instant later, sending the same color to the same part of the retina, may be a mile away. A cannon-ball, maintaining a constant average velocity, would require over seventeen years to traverse-the distance between the earth and the sun ; how long does it take light to pass over this distance ? (See page 297.) The illuminating powers of a lamp and candle are as 10 to 1. How far from the lamp, in the straight line joining the flames, must a sheet of paper be placed to be equally illuminated by both ? What would be the result if the solar light were not composed of various colors ? How is the rainbow produced ? Explain fully the action of the rain-drop in producing the primary and secondary bow. Why is a ball fired from a cannon invisible ? Because it moves with such velocity that the image on the retina does not remain sufficiently long to produce an impression. It has been photographed by the instantaneous process. I NATURE OF SOUND. Acoustics is that branch of Natural Philosophy under which is studied the origin and nature of vibrations causing sounds ; the transmission of these vibrations through gases, liquids, and solids ; and the mechanism of the organs of speech and hearing viewed as acoustic instruments. Sound is the sensation peculiar to the ear. It is caused by the vibration of the nerves of hearing. This vibration generally has its origin in some vibrating body, such as a bell, a string, or an organ-pipe, surrounded by the air. Between the vibrating body and the drum-skin of the ear, the air vibrates in unison with the vibrating body, and this air, NOTE.— Let the pupil provide himself with the articles illustrated in the introductory group above. These, in connection with the simple apparatus which he can put together in accordance with instructions given in the text, will enable him to illustrate the principles of acoustics. No. 1 is a violin-bow ; 2, an A tuning-fork mounted on resonant-box ; 3, a C tuning-fork ; 4, a sound-lens ; 5, a zither ; 6, a rotator ; and 7, an ordinary bell. The outfit will be furnished by Messrs. James W. Queen & Co., of Philadelphia, and Mr. Samuel Hawkridge, of the Stevens Institute, at price stated in the preface. brate in unison. Mechanism of Hearing. — To the drum-skin of the ear, or membrane of the tym'panuin, is attached a series of three little bones called the hammer (H), the anvil (A), and the stirrup (S) (see Fig. 256). The foot-plate of the stirrup is connected with an oval membrane which closes a hole in the inner ear. The inner ear is filled with a liquid, in which are spread out the filaments of the audiFIG. 256.-OSSICLES m tory nerve, or nerve of hearing. The drum-skin, vibrating in unison with the vibrating body and the air surrounding it, sends vibrations through the little ear-bones (ossicles) to the liquid and nerve-fibers in the inner ear, and the trembling of these nerve-fibers causes the sensation called Sound. Fig. 257 illustrates the parts of the human ear. Waves of sound are collected by the trumpetshaped external ear or pinna (1) and directed through the auditory canal (2, 3) to the drum (4). The ham- 1, pinna ; 2, 3, auditory canal, with openings of wax glands ; 4, membrana tympani, or drum-skin ; 5, portion of anvil ; 6, hammer ; 7, handle of hammer applied to internal surface of drum-skin, which it draws inward ; 8, Eustachian tube ; 9, 10, 11, semicircular canals ; 12, cochlea ; 13, 14, auditory nerve. 372 SOUND. mer-bone (6) is shown connected with the drum-skin ; the stirrupbone is attached to an oval membrane closing a hole in the vestibule of the inner ear. From this vestibule, the cavity opens into the semicircular canals (9, 10, 11), and also into a spiral cavity (12), which so resembles a snail's shell as to be called by its Latin name, cochlea. In the cochlea are the filaments of the auditory nerve (13, 14). same time vibrating with the vibrating body and the air. The Vibrating Body. — Fig. 258 represents a tuning-fork mounted on a resonantbox. If we draw a violin-bow across one of the prongs of the fork, or strike it with a stick covered with leather, we hear a sound. The fork is now in vibration, for if we touch the face of one prong with a little ball of cork suspended to a fine silk fiber, we shall see the cork violently repelled from the prong, and these blows against the cork ball will be visible until the sound becomes almost too feeble to be heard. The cork-pendulum will in like manner show the ESSENTIAL CONDITIONS OF SOUND. foil, a piece of glass blackened with camphor-smoke. The trace of the point of the foil will appear as in Fig. 259, showing that, while the glass was drawn along, the prong went many times to and fro in a direction at right angles to its path. If we had armed each prong with its own piece of foil, we should have had a double trace, like that shown in Fig 260. Such a trace proves that the prongs, in vibrating, approach each other and then recede, and that one prong makes the same trace as the other. jump up and down when the membrane is held in the air at a distance from a vibrating and sounding body. If we stretch a piece of linen paper over the mouth of a tumbler, and then cut away part of the paper till the tumbler gives forth a loud sound when the fork is brought over the opening, as shown in Fig. 261, we may place the tumbler in any part of the room, and sand on the paper will dance whenever the fork is sounded on its resonant-box, or when an organ-pipe is blown which gives the same note as the fork. If two bodies vibrate the same number of times a second, and one of them is sounded, the aerial vibrations caused by this one will set in vibration the other body, even at a considerable distance. This phenomenon is a general one, and is called covibration. It may be readily exhibited by placing two tuning-forks, which give the same note, on their resonant-boxes and at a distance of several feet from each other. If one of the forks be sounded, the other will enter into vibration. The Vibrating Ossicles of the Ear. — In Fig. 262 are presented traces obtained by Konig, of Paris, on attaching a delicate bristle to the several bones of the ear. This bristle was in contact with the surface of a revolving cylinder Our knowledge of sounds is wholly due to the interpretation of vibrations by the nerves of the ear. Hence a deaf-mute can have no conception of sounds. Vibrations, it is true, are felt, not only by the hand, but, in case of deep tones, by the whole frame. Persons born deaf may thus experience pleasure on the performance of music. Feeling vibrations, however, is very different from hearing sound. Air is not the only Medium of Transmission of sound. If the foot of the tuning-fork be screwed into a disk of wood, and this disk placed in contact with a column of water contained in a jar which rests on the resonant-box of the fork, we shall hear, when the fork is struck, a sound caused by the transmission of the vibrations of the fork through the water to the resonant-box. If, while bathing, you hold your head under the water for a moment, you will be able to hear distinctly a sound produced beneath the surface at a considerable distance. This proves that water is a transmitting medium. TRANSMISSION BY LIQUIDS AND SOLIDS. 375 may be communicated to the water of a stream by persons walking along the bank, and are immediately appreciated by the nerves of fishes insensible to sounds made in the air. Further, if a long wooden rod be placed against the head, and the other end of the rod be brought in communication with the foot of the vibrating fork, we shall hear a sound caused by the passage of the vibrations of the fork through the wood, and through the skin and bones of the head, to the nerves of the ear. The conducting power of seasoned wood fur- supplying their places with pieces of rubber or parchment, tightly wound on and connected with the ends of a long cord. If the cord be drawn tight, a conversation may be carried on between persons a number of rods apart, by using one cup as a mouth-piece and listening at the other, as shown in Fig. 263. Small pasteboard boxes may be used instead of the cups. rience the facility with which solids transmit sounds, and were in the habit of applying their ears to the earth when they suspected the approach of an enemy, or wanted a more distinct impression of any sound that attracted their attention. Sound not produced in a Vacuum. — As sound thus implies the vibration of air or some other material substance, there can be no sound in a vacuum. A bell rung in the exhausted receiver of an air-pump can not be heard. The absence of atmosphere on the moon's surface imports perpetual silence. To illustrate this principle simply, pour a little water into your glass flask, close the flask with an India-rubber cork having two holes, through one pass a glass rod, and by means of a piece of rubber tubing attach to the end of the rod a toy bell. Now apply heat until the water boils. The steam will expel the air, and, if you close the second hole in the rubber cork with a glass stopper, you will have a fair vacuum in the flask when the steam condenses. If the flask be now shaken, the sound of the bell will be extremely feeble, if not inaudible. Velocity of Sound. — The vibrations causing sound are transmitted by air at a temperature of 32° Fahr., with a velocity of 1,090 feet a second. With every rise of 1°, the velocity of sound increases by one foot. Thus, at a temperature of 85° (53° above 32°) the velocity of sound in air is 1,143 feet a second. At 60° Fahr., sound travels a mile in about 4f seconds. The velocity of sound in air is thus less than that of light; it is also less than that of a bullet. A rifle-ball reaches a deer before he hears the report ; but the flash is seen before the bullet strikes. Water-fowl learn to dive, and wary game to dodge, at sight of the flash, and so escape. With the old flint-lock fowling-piece, the flash in the pan gave longer notice of danger. The velocity of sound in oxygen gas, at 32°, is 1,040 feet a second. In hydrogen, it is 4,160 feet, or four times as great. As a cubic foot of hydrogen weighs only ^ as much as a cubic foot of oxygen, it follows that the speed of sonorous vibrations through gases varies inversely as other words, in the inverse ratio of the square roots of their densities. Sound travels more rapidly in liquids and in solids than in air. The velocity of sound in water is about 4£ times as great as in air. In steel, it is about 10J times as great. The Velocity of Sound is the same for all Notes, whether high or low. This was shown by Biot (be-or), who found that melodies played at one end of the long aqueduct of Paris reached the other end without alteration. This could not have been if the sounds composing the melodies had different rates of velocity. QUESTIONS.— What is Acoustics ? Define Sound. By what is sound caused ? Explain fully the mechanism of hearing, drawing on the blackboard a diagram of the auditory canal and inner ear. What three vibrations are implied in the sensation of sound ? Prove that the sounding body vibrates by an experiment with the tuning-fork ; with a common bell. Why is the bell stopped from ringing by touching it with the finger. Moisten the edge of a glass finger-bowl or thin goblet, and move the finger rapidly around it ; why will it give forth a musical sound ? Strike your tuning-fork, and hold a card near it ; why will you hear a continuous tapping ? Do you know how the vibrations of both prongs may be registered ? Prove that the air is in vibration when we hear a sound. Explain the phenomenon of co-vibration. What interesting experiments show that the ossicles, or little bones of the ear, vibrate in unison with the air ? Explain the difference between feeling vibrations and hearing sounds. Can you think of any causes of deafness ? Whatever interferes with the transmission of vibrations to the nerves of the ear causes deafness, as ceru'men or wax in the auditory canal, perforation of the drum-skin, or destruction of the little bones by inflammation in scarlet fever. In order that hearing may be perfect, the cavity of the middle ear, which is spanned by the three bones, must contain warm air. Nature provides for its free admission through the Eustachian (yu-sta'ki-an) tube (see Fig. 257, No. 8), which connects the middle ear with the throat. Why, then, is temporary deafness produced by a cold ? Can you think of a reason why exposure to loud noises may be injurious to hearing ? Why, boxing the ears ? Surf -bathing ? A severe blow on the head ? Is air the only medium of transmission of sound ? What evidence is there that water transmits vibrations ? Do fish hear ? How ? Describe an easy method of detecting a rotten spot in a wooden beam. What is the string telephone ? Why can you hear a train coming by placing your ear on the rail, when the air conveys no perceptible sound of its approach ? How can you show that sound is not transmitted in a vacuum ? State the velocity of sound at 50* Fahr. ; at 70. What familiar example can you give to prove that sounds of all kinds travel at the same rate ? Do all substances transmit sound with the same velocity ? What is the velocity of sound in water ? In steel ? Standing in a lumber-camp, at some distance from a wood-chopper, I hear the blow of his axe 2i seconds after I see the chips fly. Suppose the temperature to be 34° Fahr., how many rods am I from the chopper ? Principle of Transmission. — Before beginning the study of the nature of sound transmission, it will be necessary to understand the following experiment with glass balls, showing how vibrations travel through elastic bodies. Fig. 264 represents a wooden railway about 6 feet long. It is made of thin strips of pine, placed side by side, about an inch apart, and joined by cross-pieces. The cross-piece at the center is screwed down to the table, and the ends of the elastic slips are then raised on blocks. Place a few large glass marbles in the middle of this curved railway, and then bring one to the end and let it roll down against the others. The marbles will remain stationary except the farthest one, which will fly up the incline toward the other end of the railway and then roll back again, causing the first marble to ascend the incline on the right. This action will continue till friction brings the marbles to rest. The marbles employed in the experiment are very elastic. This is proved by rubbing a slab of stone with a mixture of oil and red lead and placing a marble on it. The marble will be marked by a small circle of red ; but if we allow it to fall on the stone, a much larger circle of red will be made, showing that the marble must have flattened when it struck, as it evidently touched a larger surface of the stone. The first marble rolls down the railway and strikes the second, which is thus flattened between 1 and 3, as shown in Fig. 265. Marble No. 2 at once springs back into its former spherical figure, and in so doing brings No. 1 to rest and flattens No. 3, as shown in Fig. 266. Marble No. 3 then springs to its former spherical figure, bringing to TRANSMISSION OF SONOROUS VIBRATIONS. 379 rest No. 2 and flattening No. 4. Thus each marble receives the blow of the marble behind and passes it on to the one in front, and we have a series of contractions and expansions running rapidly through the the railway. Compression and Expansion in a Tube. — Similar actions take place in successive portions of air as sonorous vibrations traverse them. In Fig. 267, a long tube, dfge, is open at/# and closed at the other end by a piston «, which can be moved forward and backward in the tube. Suppose the piston a to move quickly forward to the position b ; then, if the air were inelastic and incompressible, a portion of the column of air equal to that from a to b would be pushed ou of the end of the tube at fa. reached b. The length be of this compression is found thus : The compression can travel only as fast as the velocity of sound, which at 40° Fahr. is 1,100 feet a second ; so that if the piston takes y^ of a second to go from a to b, the length of the compressed air, b to c, is -^ of 1,100, or 11 feet. If the piston takes -nf^ of a second to go from a to b, then the depth of the compressed air is y^ of 1,100 feet, or 1^- feet. At the moment the piston a reaches 5, we have compressed air in the tube from b to c. This compressed air is elastic — like a bent spring, or one of the glass marbles used in the previous experiment ; it at once expands, and in the same time (assumed to be y^ of a second) that was occupied in its compression. It presses against the interior of the tube and against the piston at b ; but these do not yield. It also presses and at the same time expands in a forward direc- tion, toward the mouth of the tube, and in the next ToW of a second it has by this expansion compressed another mass of air, c to c', equal in length to b c. In compressing the column c c', the air in the column b c expanded to its natural volume. The column c c' next expands as did the column b c. But it can not expand backward, because the column of air b c has expanded with rapidity to its natural volume in compressing c c', and therefore tends by its momentum (like a swinging pendulum) to expand still further — which action just balances the backward expansion of the air in c c', so that the column of air b c now acts like the solid piston against the column c c'. Thus the compression is sent through the air of the tube with a velocity equal to that of sound, and by a series of actions similar to those which took place in the row of glass balls in the previous experiment. If we now suppose the piston to move in y^ of a second from b back to a, the air from a to c will be rarefied, and the actions following will be similar to those which took place with the column of condensed air, only a pulse of rarefied air will now travel through the tube instead of one of condensed air. The Effect of Compressing Air is to bring its molecules nearer together, while rarefaction separates them. Hence, if we imagine the piston to vibrate regularly from a to b and back from b to «, like a pendulum, or as the prong of a tuning-fork really does, we shall have the molecules of the air in the tube making short vibrations forward and backward, each molecule having the motion of a pendulum. vibrations a second. Sound-Waves in the Air. — If instead of a piston moving to and fro in a tube we have a tuning-fork or other musical instrument vibrating in the open air, the condensation and rarefaction of the air will not be confined to one direction, as in the tube, but will spread all around ; so that we shall have spherical shells of compressed and rarefied air continually following one another, as they expand outward in regular order and motion, like the outward movement of circular water-waves around the place where a pebble has been dropped into a pond. The depth of air embracing any condensed, and the adjoining rarefied, shell of air, is called a sound-wave. This sound-wave is entirely different from a water-wave, in which the water vibrates up and down in a direction perpendicular to that of the wave's progress. In a sound-wave the vibratory motions of the air are not perpendicular to, but in the same direction as, the direction of motion of the soundwave. To represent a Sound-Wave, a curve is used called the sinusoidal curve (see Fig. 268). In this figure, the line A B, which is the axis of the curve, represents the direction of the sound vibrations. The lengths of lines drawn perpendicularly from this axis to any point of the curve represent the amount of compression or of rarefaction of the air. Thus, at the points A, C, and i length e f represents the amount of rarefaction — lengths above the line being assumed to stand for compressions, and lengths below the line for rarefactions. The whole length A to B is a wavelength, while the length A to C, j to &, or 0 to B, is a halfwave length. Although the nature of a sound-wave has been known since the time of Newton, and although this curve representing its nature has been used during almost as long a period, yet many have confounded the curve — a mere symbol — with the sound-wave itself, and have been led into gross errors by supposing a sound-wave to be composed of waves shaped like this curve and progressing through the air with heaps and hollows like the waves of the ocean. The Nature of a Sound-Wave, and the manner in which it travels through an elastic medium, are nicely represented in an ingenious apparatus invented by Crova. In ence into 12 equal parts. Draw the line A, B, 24. Take the length A B with dividers, having a drawing-pen with India-ink in it, and, placing the point of the dividers on division 1 of the small circle, describe on the cardboard disk a circle having a radius of A B. Then take a radius A to 1, and with center 2 on small circle describe another circle. Then with radius A 2 and center 3 on small circle, describe on the cardboard a third circle, and so on, taking radii successively greater by one division on the scale A 24, and drawing circles with centers on successive points of the circle C. A piece of cardboard having a slit cut out of it (shown in No. 6, page 370) is placed horizontally so that only short lines of the circles are seen in the slit. On rotating the disk, these short lines, which stand for molecules of the air, will be seen to move backward and forward like so many little pendulums, producing in the row of lines a horizontal, worm-like movement. This movement causes a wave to appear at one end of the slit, move along, and disappear at the other end, by the successive crowding together (condensation) and separation (rarefaction) of the row of dots. If we examine closely the cause of this progressive wave-motion, we shall see that each dot moves only backward and forward ; but as these motions of vibra- tion are successive and not in unison, it is evident that we have a series of condensations of the dots, alternated with a series of separations or rarefactions, following one another in a uniform movement and order, and progressing along the slit. This pictures to the mind the motion of successive condensations and rarefactions in the air as sonorous vibrations pass through it. In an Experiment described by C. J. Woodward, of Birmingham, England, the same progressive motion of the condensations and rarefactions of a sound-wave is obtained directly from the vibrations of small pendulums. A row of pendulums of equal length is suspended from a rod, A B (Fig. 272). In order to start the pendulums, the bobs are placed against an angular-shaped board F C I), the rod being held in a plane slightly behind the plane of the board. If, now, the rod. and pendulums are raised together vertically, I will first swing, then Jc, and so on, till all are free. When as they vibrate to and fro. Such an arrangement has been used to illustrate wave-motion, as each bob moves with harmonic motion — i. e., a motion like a pendulum's ; but it does not illustrate directly those compressions and rarefactions whereby sound is propagated. A change of position of the rod, however, at once makes it do so. If, while the pendulums are vibrating, the rod from which they are suspended be turned in the horizontal plane through a right angle, the direction of the swing of each pendulum is not changed, and all the pendulums swing in the same plane. This will become clear from Fig. 273, where the pendulum-bobs viewed along O X appear to trace out wave-motion. The relative position of the bobs, after the rod which supports them is turned through a right angle, is shown along 0 Y. The motion then illustrates mechani- from threads 30 centimetres long, were found to answer the purpose. Interference of Sound. — If a condensed half-wave meets a rarefied half-wave, and these half-waves have the same length and the same extent of vibratory motion, then they must neutralize each other's action in that part of the air where they meet, and no motion results from their combined action. The reason of this is that, while the condensed half -wave tends to force the molecules of air closer together, the rarefied half- wave tends with an equal energy to separate them ; so they remain at rest, and at the place of meeting of the half-waves there is no sound. This fact is made apparent in many experiments. The trace obtained simultaneously from the two prongs of a vibrating fork (see Fig. 260) shows that these prongs move apart and then draw together, each making the same _,- ------ ^ number of vibrations in the same time. When the prongs of a fork approach each other, the air is condensed in front of the space between the prongs, and rarefied in front of the flat faces of the prongs ; and when the prongs separate, the air is rarefied in front of the space between FIG. 274. -INTERFERENCE OF the prongs, and condensed in front we nave at the same instant lour equal actions, whose combined effect on the air is shown in Fig. 274 when we look down upon the tops of the prongs c c. Imagine the prongs swinging away from each other in their vibration. Then the action of the faces c c on the air is to condense it, and this condensation tends to spread all around the fork; but by the same movement of the fork the space r r between the prongs is enlarged, and hence a rarefaction is made there, and this rarefaction also tends to spread all around the fork. also produced when two sounds fall at the same time on the ear, and one of these sounds is slightly natter or sharper ' than the other. This phenomenon is always observed when two organ-pipes, forks, or any two musical instruments are slightly out of tune. The experiment is readily made with two forks which, previously in tune, are put out of tune by loading the prong of one with a small piece of wax and thus flattening its note. This decrease in the frequency of the vibrations of the loaded fork makes it give wave-lengths in the air which are longer than those given by the unloaded fork. it follows that at a certain instant the condensation in two waves, one from each fork, will reach the ear at the same moment. Their united action will produce a sound greater than that given by the vibration of either fork alone, and consequently we hear a louder sound. The same increase in loudness occurs when rarefactions in the two sounds fall together on the ear ; but just between these periods of increased loudness there is an instant when the sound becomes very feeble. These actions give to the sound a thumping character called beating. Fig. 277 explains the action of the two series of sound-waves on each other. The longer waves are indicated by the full line ; the shorter, by the dotted line. These waves are going from A to B. An ear at B, as implied in the figure, is receiving a condensed half -wave from one source of sound, and a rarefied half wave from the other. A very feeble sound is the result ; but when by the forward motion of the Reflection of Sound — Like light and radiant heat, sound is reflected, and in such a manner as to make the angle of reflection equal to the angle of incidence. Spherical mirrors may be used to prove the principle. Determine the point to which rays of light converge if transmitted from some distant source of illumination to a mirror, and reflected therefrom. Substitute a watch for the light, and hold the ear at the point of convergence. The ticking will be heard distinctly, as if it came from the mirror, instead of the watch. The wet sails of ships, when bellied by the wind, have been known to reflect, to ears that happened to be at their foci, sounds produced at great distances. Apartments in which reflections are produced by the walls are called Whispering Galleries. The dome of St. Paul's, London, and that of the national Capitol, furnish examples of modern whispering galleries. One of the most remarkable structures of this kind in ancient times was the Ear of Dionysius, a dungeon so called from the tyrant of Syracuse, and constructed in such a way that by stationing himself at a particular point he could overhear the unguarded words of his prisoners. Echoes are merely repetitions of sounds by reflection from walls, mountain-sides, etc. The interval that must exist between the sound and the echo may easily be determined if the distance of the reflecting surface is known. Thus, for a distance of 112 feet, the interval at 62° Fahr. is equal to 112x2 (the entire distance traveled by the direct and reflected sound) divided by 1,120, the velocity of sound at that temperature of the air, or one fifth of a second. If we assume that five syllables can be pronounced rapidly in a second of time, then it is evident that at distances less than 112 feet there can be no distinct echo, even of a single syllable ; the reflected sound mingles with the direct sound of the speaker's voice, and often confuses his utterance. This is noticeable under stone arches and in large unfurnished rooms. The echoes of a room are modified or removed by furniture and hangings ; the presence of an audience in a theatre or church will quench sound-waves and thus destroy disagreeable reverberations, for sound is absorbed like light and heat. The same sound may be repeated more than once. There are echoes that repeat a syllable twenty and even thirty times. Mountain-regions afford numerous examples of multiple echoes. The property possessed by long tubes of conveying sound accurately, is due to repeated reflection. The waves of sound, being reflected from the interior of the tubes, are prevented from dispersing as in the open air (see page 380), and hence are but slightly diminished in loudness. The French philosopher Biot found that he could, without raising his voice, converse through an empty pipe three fifths of a mile long. This fact has been turned to account in many ways ; the common speaking-tube is familiar to all. The short speaking-trumpet, however, does not act by reflection, but is thought to owe its effect partly to resonance and partly to the vibration of its flaring bell, or pavilion. Ear-Trumpets, used by deaf persons, concentrate and reflect vibrations to the interior of the ear, and thus render audible, sounds that could not otherwise be heard. The outer part of the ear is itself of such a shape as to collect the sound-waves that strike it and reflect them to the membrane within. To enable them to hear more distinctly, we often see persons putting up their hands behind their ears so as to form a concave reflecting surface. In this case, the hand acts somewhat on the principle of the eartrumpet. Instinct teaches animals to prick up their ears when they want to catch a sound more clearly. Au'diphones are instruments designed to collect soundwaves and transmit the vibrations to the nerves of hearing through the bones of the head. They sometimes have the form of a fan when intended for ladies' use, and are pressed against the upper teeth. Kefraction is a property of sound. To prove the refraction of sound in passing from one conducting medium to another, a lens 12 to 18 inches in diameter has been constructed by stretching and securely fastening thin sheets of India-rubber on a wide grooved brass ring, and inflating the cavity between them with carbonic acid or some other gas (see No. 4, page 370). The ticking of a watch suspended on one side of the sound-lens can be distinctly heard at the DIFFRACTION OF SOUND. 389 corresponding focus on the other, while almost inaudible between the two points. This could not be so unless the sound-waves from the watch, in passing through the lens, were bent toward its axis. Sound is also diffracted — that is, the sound-wave is bent round obstacles in its path, like houses, etc., which, however, tend to " shade off " the sound, or produce an illdefined sound- shadow. The diminished intensity in the sound of a railroad train as it enters a cutting is due to the fact that the observer is in such a shadow. In the acoustic shadows cast by buildings, the air-shocks attendant upon explosions are sensibly modified. QUESTIONS.— Explain the nature of the Transmission of Sound by means of the experiment with the elastic marbles. By what are the sounds ordinarily heard transmitted ? Describe compression and expansion as illustrated in a glass tube. Explain condensation and rarefaction, and state the effect of each on the molecules of air. Strike your tuning-fork and hold it near your cheek. Why will you feel little puffs of air ? Now, describe accurately a sound-wave and compare it with a water-wave. Can you represent a sound-wave on the blackboard, showing how the condensation and rarefaction constituting it are produced ? Construct a Crova's disk, mount it on your rotator, and illustrate the nature of a sound-wave, and the manner in which it is propagated. Describe a more recent experiment which aptly illustrates the same principle. What is meant by the Interference of sound ? How is it produced, and how can it be rendered apparent ? Why are there four places of silence in one rotation of a vibrating tuning-fork ? How can this be proved with the fork, and a common tumbler partly closed by a piece of glass ? Suggest another illustration of the interference of sonorous vibrations. What are beats of sound, and how are they produced ? Under what circumstances may the phenomenon be observed ? Draw a figure explanatory of the action of two series of sound-waves on each other in producing beats and interference. How can you illustrate the Reflection of Sound ? Are woven fabrics good reflectors ? JVb, because they are pervious to sound. What are whispering-galleries ? Define Echoes. What conditions cause single echoes ? What, multiple echoes? On what does the number of syllables repeated depend ? When is there no perceptible echo ? Why do the echoes of an empty building disappear when it is filled with people ? Explain the principle of the speakingtube ; of the speaking-trumpet ; of the ear-trumpet ; of the audiphone. Why do animals change the positions of their ears ? Illustrate Refraction of sound ; Diffraction. In arctic regions, persons separated by more than a mile of frozen water have conversed with ease ; can you suggest a reason ? In such cases, the air is homogeneous, and offers no obstacle to the free transmission of sound-waves. Masses of unequally heated air enfeeble sound, the waves being broken up by refraction. Why, then, can sounds often be heard farther at night than by day ? between which it is stretched. The cause of this vibration is the successive stretching and relaxing of the string; for, evidently, when it is pulled to C, the length A B has become A C -j- C B, which is longer than A B. catgut, etc., are as follows : 1. The force with which the string is stretched remaining the same, the number of vibrations in a given time are inversely as the length of the string. Thus, strings of lengths 1, 2, 3, 4, will have 1, -J, £, and J the number of vibrations in the same time ; while strings of lengths J, J, J, will vibrate 2, 3, and 4 times as rapidly as the string of the length 1. 2. In strings of the same substance and length, and stretched with the same force, the vibrations will be inversely as their diameters. A string 3 feet long, having a diameter of -fa inch, will vibrate twice as many times in a second as a string of the same length and -fa inch in diameter. 3. In strings of the same length and of the same diameter, the number of vibrations varies as the square root of the stretching force. Thus, if a string be stretched with forces of 1, 4, 9, 16, 25, the number of its vibrations a second will be as 1, 2, 3, 4, 5. equally stretched and of the same length and diameter weigh respectively 1, 4, 9, 16, 25, the numbers of their vibrations per second will be as 1, £, £, J, \|, of the string having the weight of 1. The Sonometer. — These laws have been determined by experiments with the Sonom'eter (Fig. 279), a long resonant-box, M N, having two bridges, B and B' near its ends. The string, gut, or wire, is attached to the pin P, and box gives the length of the string between the bridges. On vibrating the string by plucking it at its center, we hear a definite musical note, which rises in pitch as we shorten the string by sliding the bridge B' toward B. If we move B' to one half the distance B B', and then vibrate the string, we hear a note which is the higher octave of the note given by the whole length of the string. As we shall see farther on, the octave of a note is given by doubling the frequency of its vibrations. Thus, half a string stretched with the same force vibrates twice as many times a second as the whole length. If we sound one quarter of the string, we get the second octave above that given by its whole length. This implies that when one quarter of the string is vibrated, it makes four times as many vibrations a second as its whole length. The second, third, and fourth laws, are proved by vibrating wires having different diameters and stretched with various weights, or having the same length and diameter but differing in weight. and B. Place the beard of a quill at n' (in the top figure), and draw a violin-bow across the wire near v. Then lift the quill from the wire. We now see the wire vibrating as if formed of two wires, A n' and n' B. At n' the wire is at1 rest, or nearly so. This point is called a node. At v and v' is the greatest excursion or bellying of the string, and these places are called the venters (Latin, venter, the belly). The two parts of the string vibrate with a seesaw motion about n\ so that v and v' in all the diagrams of Fig. 280 are always moving in opposite directions. When the string vibrates with two venters, it gives out the higher octave of the note it gave when it had only one venter. In the second, third, and fourth diagrams of Fig. 280, with 3, 4, and 5 venters respectively, the string makes 3, 4, and 5 times the number of vibrations it gave when it vibrated with only one venter. If the number of vibrations a second is 100 when the string vibrates with one venter, then it will make 200, 300, 400, and 500 vibrations when it has 2, 3, 4, and 5 venters. If the string is so stretched that it gives out the note C below the middle C of the piano (shown in the bass clef, Fig. 281) when it vibrates with one venter, it will give the notes numbered 2, 3, 4, 5, 6, 7, 8 (shown in the treble clef), when it vibrates with 2, 3, 4, 5, 6, 7, 8 venters. These notes are called the harmonics of the note in the bass clef, and are given by 2, 3, 4, 5, 6, 7, 8 times the number of vibrations given by the C in the bass. Under Analysis of Sounds, we shall see that, when a piano-string is struck by its hammer, all these harmonics except the seventh are present in its sound. The nature of vibrations in strings may be effectively studied by means of the zithern, a cheap toy consisting of a sounding-board crossed by 24 wire strings (see No. 5, page 370). If a finger be placed on the center of one of the strings and the string be then vibrated, it will yield a note an octave higher than its fundamental note. The Vibrations of Rods, Tuning - Forks, and Reeds. — A rod, clamped in a vise, is shown at #, #, c, d, e, in Fig. 282. If we pull the rod aside, it will vibrate till the energy of same kind of motion as that of a swinging pendulum ; so have all bodies, such as strings, prongs of tuning-forks, plates, membranes, air in organ-pipes, etc., which give forth musical sounds. If we place a soft body at the nodal points of &, c, d, e, and draw a bow across the rod near the center of a venter, the rod will, like a string, divide itself into segments of vibration with nodes, as shown in the figures, and the sounds given by the rod when it has these nodes will be far sharper than the sound given when the rod vibrated, as shown at a. An interesting example of a vibrating rod is a tuning-fork, and you here have the analysis of its motions as determined by experiments. Let a a in Fig. 283 represent a steel bar resting on cords at points approached each other, as is shown by the dotted lines, till in the tuning-fork they are close together (p and q) and near where the prongs of the fork curve inward. The fork (Fig. 284) now vibrates like the unbent rod out of which it was formed, oscillatting to and fro about its nodal planes. The prongs approach each other, then recede. When they approach, the foot of the fork is pushed down. When they recede, the foot moves up, and thus the fork communicates its vibrations to any body on which it may be placed, for example, to a resonant-box of such interior dimensions as to be in tune with the fork. In various musical instruments, thin plates or rods are used. Thus, in the zylophone, vibrating wooden rods, and in the glass harmonica, strips of glass, are supported at their nodes on cords. These rods or glass plates are struck with a light wooden hammer, and give sounds of life and brilliancy. In the common music - box, free steel tongues, arranged in the form of a comb and made fast at one end, vibrate at the other when lifted by the pins of a revolving cylinder, yielding their individual notes. In the vox-lmmana and other reed-pipes of the organ, in the reed-organ, and in the clarionet, reeds or thin plates are set in vibration by blasts of air. The sounds given by these reeds are re-enforced and modified by their setting in vibration the air contained in pipes or cavities of various forms and sizes. Vibrations of Plates. — When a circular plate of brass, glass, or other elastic substance, is fastened at its center to a support, and a violin-bow is drawn, perpendicularly to the surface of the plate, across causing it to vibrate, he saw the sand at first violently agitated, but in a few moments come to rest in narrow wind-rows running from the center of the plate, as shown in Fig. 285. These figures, formed by sand on vibrating plates, are hence called Chladni's figures ; and-the lines of rest, nodal lines. The plate always divides into an equal number of vibrating sectors. This is explained by the well-established fact that, in adjacent sectors, it always vibrates with opposite directions of motion ; the line of sand separating any fingers. A characteristic figure will be immediately formed. Vibrations of Bells. — A bell may be considered as a plate formed into a spherical surface. Bells have nodal lines or planes of rest, and ventral surfaces where the vibrations are greatest, and opposed in direction on opposite sides of the nodal lines. Fig. 287 shows how a bell struck by the SOUND, clapper at #, #, c, or d, will have at these points the center of a venter, while the nodal points are half-way between these points, at n> n, n, n. The nodes _JL_ and venters may be found by suspending to a string a small ball of ivory or of metal. When the ball touches the bell at #, #, c, or d, it a\ is violently repelled, while at ft, n n> n, it is very slightly agitated. Vibrations ol Columns of Air. — Fig. 288 represents a glass tube, T, with a cork in it which can be slid to various positions. By adjusting the cork we obtain various depths of air in the tube, from its open mouth I to the cork c. On vibrating a tuning-fork over the mouth of the tube, while the cork is gradually slid along the tube, we soon learn that, ly increased in loudness ; and that, when the cork is removed from this position, the sound rapidly diminishes in intensity. If the diameter of the tube be small compared to its length, we shall find that the re-enforcing of the sounding-fork reaches its maximum when the depth of the column of air measures one fourth of the wave-length of the sound given by the fork. The simple formula I = — , in which I = the length of the soundwave, v = the velocity of sound at the temperature of the air in the tube, and n = the number of vibrations a second made by the fork, gives us the means of determining the length of \ of the sound-wave propagated by the fork. If, for example, the fork makes 256 vibrations The explanation of the above fact is as follows : The prong of the fork and the air at the mouth of the tube must vibrate together ; otherwise, there will be interference between these vibrations, and the air in the tube can not vibrate with the fork and re-enforce the sound the latter originates. We have previously learned that the fork, in going from a to & (Fig. 288), makes one half wave-length in the air before it. This may be represented by the curve bed, above the line b d. Now the tube T must be as long as from b to c, or one quarter of a wavelength, so that, by the time the prong of the fork has gone from a to b, and is just beginning its back-swing from b to «, the half-wave bed has just had time to go to the bottom of the tube T, to be reflected back, and to reach the prong b at the very moment of its back-swing. If it does this, then the end of this reflected wave (shown by the dotted curve on the tube T) moves backward with the back-swing of the prong &, and thus the air at the mouth of the tube and the prong of the fork swing together, and the sound given by the fork is strengthened. It is evident that, if the fork makes double the number of vibrations per second over the mouth of the tube, the column of air in the tube will have to be shortened one half in order that it may resound ; and, if the fork makes half the number of vibrations, the depth of air in the tube will have to be doubled to re-enforce the sound of the fork. In other words, the laws ruling these phenomena of resonant tubes are, that the lengths of resonant tubes are inversely as the number of vibrations to which they resound. Organ-Pipes are simply resonant tubes. The air in such pipes is set in vibration by vibrating reeds, or by air driven through a mouth-piece like a whistle's, instead of by the fork as in our experiments. The relation between the lengths of organ-pipes and the numbers of vibrations they give is approximately the same as in the case of resonant tubes, viz., the numbers of vibrations a second given by organ-pipes of similar form are inversely as their lengths. vibrations of the fork per second, or w, and, by the experiment cited above, obtain the length of the wave, or /, then we may compute the velocity of sound in air at 65° Fahr. by multiplying n by L In the experiment given, n equaled 256, and I was 4-38, and 256 x 4-38 =• 1,121. This is one of the methods which has been used to obtain the velocity of sound in various gases. QUESTIONS.— State the laws that govern the Vibrations of Strings. By what experiments have these laws been determined ? Describe the Sonometer. Mention the variety of notes given by a stretched string. What will be the effect of halving its length ? Of quartering its length ? What is a node ? A venter ? Explain what is meant by the harmonics of a vibrating string. They are " the notes corresponding to the division of the string into its aliquot parts." What practical use may be made of the zithern in this connection ? Draw on the blackboard a series of figures showing how a rod may be made to divide itself into segments of vibration, like a string. When will the sound be higher pitched ? What interesting analysis of the motions of the tuning-fork can you give ? How may musical tones be obtained from vibrating rods, plates, and reeds ? Describe the principle of the common music-box. What are Chladnrs figures, and how are they produced ? Illustrate, by means of a diagram, the nodal planes and ventral surfaces of a bell. How may the nodes and venters be detected ? What is meant by re-enforcing the sound of a tuning-fork ? In the case of the fork and the resonant tube, when does this re-enforcement reach its maximum ? What formula affords a means of determining the length of sound-wave propagated by the fork ? Define a wave of sound, and wave-length. What are organ-pipes ? What relation exists between their lengths and vibrations ? Pitch is that quality of a sound by which we distinguish its position in the musical scale. Thus, we speak of a sound being higher or lower than another. Pitch depends on the number of vibrations made by the sounding body in a certain fixed unit of time, the second.* The greater the num- * In this country, and in England and Germany, a vibration is understood to be a movement to and fro of the vibrating body. In France, a vibration is a movement to or fro. Hence the vibrations given by French writers have to be halved to correspond with those we use. PITCH. ber of vibrations, the higher the pitch. Thus, if we have three sounds, and the numbers of their respective vibrations are to each other as 1 : 2 : 4, then the second is one octave above the first, and the third is an octave above the second and two octaves above the first. BER OF VIBRATIONS. As some persons are born color-blind, so there are others who are deaf to certain notes. Most men lose the power of appreciating very high notes with advancing age, and sudden shock or prolonged mental strain has been known seriously to impair the sensibility of the ear to sounds of different pitch. "We have seen that there are many objects invisible to the unaided eye ; so there may be sounds produced by insects (implying over 30,000 vibrations to the second) that are wholly inappreciable by the human ear. That the Pitch rises with the Number of Vibrations, is proved by the simple apparatus shown in Fig. 289. A cardboard disk about 8-J- inches in diameter revolves about each series equally spaced on its respective circle (see Fig. 290). On the first or inner circle are 24 holes, on the second 30, on the third 36, and on the fourth 48. These numbers are disk with a uniform motion and blow through a glass tube placed close to and opposite the inner series of holes, we shall produce a sound having the character of a musical note. This sound is caused by vibrations made by the puffs of air which pass through the holes as they successively come in front of the tube. If we pass the tube from the first to the second, third, and fourth ring of holes, the sound at each new position of the tube rises in pitch, and the ear distinguishes in the sequence of these sounds the major chord. In other words, if we rotate the disk so rapidly that we obtain from the first series of holes the C of the treble, then from the second, third, and fourth series of holes we shall have the sounds of E, G', and C' of the octave above the treble C. These musical intervals are always given by sounds whose vibrations have the ratios of 4 : 5 : 6 : 8. If we hold the tube stationary before any one of the series of holes, we shall find that the sound rises in pitch as we increase the rapidity of rotation, and falls as we slacken the speed of the disk. The Siren (Fig. 291) is an instrument similar in action to the one just described, and much used to determine the pitch of sounds. It consists of a metal cylinder into whose base air is blown. The top of the cylinder is perforated with a number of holes. Just over this top, and nearly touching it, rotates a metallic disk on a vertical axis. This disk is perforated with the same number of holes as are in the cylinder. The form of the holes is shown in section in the figure. They do not pass perpendicularly through the plates, but slope contrariwise, so that the air when forced through the holes in the top of the cylinder impinges on one side of the holes on the rotating disk, and thus blows it round in a definite direction. The disk, in making one revolution, opens and shuts the holes as many times as there are holes in the disk and cylinder, and hence the wind escapes from the cylinder in successive puffs, the frequency of which depends on the velocity of rotation. A sound is thus produced whose pitch rises with the velocity of the disk. The vertical axis of the disk has a screw cut on it which works on a notched wheel To determine the pitch of a sound with this instrument, we gradually increase the rotation of the disk until the sound given out approaches the pitch of the sounding body the number of whose vibrations we would determine. When the two sounds are quite near in pitch, the ear perceives distinct beats produced by their joined action on the air. The velocity is now cautiously increased by regulating the blast of air through the instrument until the beats just disappear. The disk is then allowed to run for a known number of seconds, during which it is connected with the counter. The number of rotations is thus recorded. If this number be multiplied by "the number of holes in the disk, and the product divided by the number of seconds the disk was connected with the counter, the number of vibrations per second causing the sound in question will be determined. The Intensity of a sound depends on the energy of the air vibrations which strike the ear, and therefore on the amplitude or extent of the vibrations of the sounding body itself. The loudness of two sounds of the same pitch varies as the square of the amplitude of the air vibrations. After a gong has been struck, the effect on the ear gradually diminishes, as the vibration is contracted in extent, during the return of the vibrating surface to rest. The intensity of sound, like that of light, has been found to vary inversely as the square of the distance. Furthermore, it depends on the density of the medium in which the sound originates and is propagated. The denser the air the louder the sound, because the quantity of matter impinging on the drum-skin is greater. Hence, sounds produced on high mountains, where the air is rarefied, are correspondingly diminished in intensity. We have seen that in a vacuum there can be no sound ; but in the pneumatic cais'son employed in constructing bridge-piers in deep water, the air is unnaturally compressed, so that conversation in ordinary tones is painful to the ear. Timbre is a quality of sound which affords a striking analogy to color in light. We may have a red and an orange light, both of the same intensity ; but the eye distinguishes one from the other. So we may have sounds of the same intensity and pitch, one from a tuning-fork, the other from a violin, piano, clarionet, or the human voice. Yet the ear distinguishes these sounds, and we readily name the source of origin in each case. German authors have an expressive term for this quality of sound. What we call timbre they call Klangfarle, which in English is literally sound-color. The different timbres of sound are produced by mingling various simple sounds, just as any color may be formed by mingling various proportions of red, green, and violet. A Simple Sound is one in which the ear can distinguish only one sound of one pitch. Such is the sound of a tuning-fork vibrating gently on its resonant-box. The sound. All simple sounds have the same timbre. The sound of a piano-wire is an example of a Composite Sound, for it is composed of the mingling of several simple sounds. Thus, if we strike the treble or middle C of the piano, the educated ear can readily detect other and higher sounds mingled with that of this C. The latter sound is, however, the lowest in pitch and the strongest of the component sounds; but it is always accompanied by these higher sounds whose vibrations bear to those of C the ratios of 1:2:3:4:5:6:7:8, etc. These sounds are called the harmonics, or overtones, of C (see page 391). If we designate the treble C by Ca, then the harmonics mingled with Ca are as follows: C3, G3, C4, E4, G4, B(,4, C6, etc. The seventh harmonic, or B^4, is wanting in the series, because the hammers of the piano strike the strings 'at points about one seventh of their length; and therefore this harmonic can not sound, for the blow of the hammer makes a venter at the point it strikes. For the seventh to appear there would have to be a node at this point. The seventh is thus purposely obliterated from the compound sound, for it is not in harmony with the other harmonics. Analysis of the Sound of a Piano-String. — That these harmonics exist in the sound of the treble C2 of the piano, is easily proved by the following interesting experiment : Depress slowly and firmly the key of C3 on the piano. The hammer will rise, press against the wire, and fall from it ; but the damper of this string will remain raised. Now, strike strongly the key of C3, and after holding it for an instant stop its sound. We shall hear the sound of C8 very distinctly, showing that it had been set into vibration by the vibration of C2, and that 08 must therefore exist as one of the component sounds of C2. In like manner one can show that G3, C4, E4, G4, GB, etc., are components of the compound sound of the wire of C2. tering into the formation of any complex sound. The sounds used in music are all complex, for a simple sound is without expression, lacks feeling or " brilliancy." We have already explained one method of analysis in which we have utilized the principle of co-vibration (see page 373). There are others which employ this same principle. Suppose we wish to analyze the very complex sounds given by reed organ-pipes. Let us arrange around the mouth of the pipe tuning-forks mounted on their resonant-boxes. The lowest sound rendered by the pipe, or that of the note by which the pipe is denoted in the musical scale, is given by the fork lowest in pitch in the series of forks. On sounding the pipe, this fork will enter into vibration ; and on stopping the sound of the pipe, the fork will sing out clearly the pipe's lowest or fundamental tone. But if we also have other forks whose vibrations per second bear to those given by the first fork the ratios of 2:3:4:5:6:7:8, etc., they will also sing out their respective notes ; and when we stop the sound of the pipe, the united sounds or chorus of the forks will very well reproduce the peculiar timbre of the reed organ-pipe. He employed a series of hollow brass or glass spheres, each having a circular opening a to ad, mit the vibrations of the outer air to the air in the interior of the sphere. Opposite this opening is a nipple £, which fits in the ear, and thus conveys the vi- orations to the auditory nerves. Each resonator is made of such dimensions that it is accurately in tune with a known simple sound, and the note of this sound is marked on the resonator. When this note is sounded in the air, the air in the resonator co-vibrates to it, and the sound of the note is heard with great distinct- be in any complex sound. By applying one resonator after another to the ear, we analyze a sound into its components. It is thus found that the analysis of the sound of the piano-wire is the same that was reached by our experiment ; that the sounds of a clarionet are formed only of the odd harmonics, or of simple sounds in the ratios of 1 : 3 : 5 : 7 ; and that the sounds of a flute are substantially those of a note and its octave. The Musical Scale is- formed of sounds differing in pitch by definite ratios of vibrations. The experiments with the simple siren (Fig. 289) showed that, when the ratios of the frequencies of the vibrations of four notes were as 4 : 5 : 6 : 8, we obtained a succession of sounds — so that, if the sound beginning the ratio, or 4, was that of the note C, then the other sounds were as follows : E, G, and c, of the octave above C. But this ratio of 4 : 5 : 6 serves to form the whole of the natural scale of music, thus : We decide on the number of vibrations a second which shall denote the treble C — 264, for instance. Then— 24 : 27 : 30 : 32 : 36 : 40 : 45 : 48 If we perforate the disk of the siren (Fig. 291) with holes arranged in 8 circles — the inner circle having 24 holes, and the succeeding circles 27, 30, 32, 36, 40, 45, and 48— then, on rotating the disk so that we obtain 264 vibrations a second by blowing through the circle of holes outer circle. This natural scale is the only one which gives perfect harmony of chords. It is the scale which good singers use, and which the accomplished violinist produces from his instrument. But the extensive use of musical instruments with fixed tones, like the piano, melodeon, organ, and many windinstruments, has given rise to a scale called the equal-temperament scale. In this there are twelve notes, aud the octave is divided into twelve equal intervals. Each of these intervals is called a semitone, and two intervals form a tone. The ratios above are given to the nearest integer. Where the note is slightly sharper, + is placed after it ; where slightly flatter, — follows it. For comparison, the ratios of vibration-numbers of the perfect or natural scale are written under those of the equal-temperament scale. The intervals of the equal temperament scale are so near to perfection that, when a succession of notes is sounded in a melody on the piano or organ, only the cultivated ear of a musician can detect the departure from accurate tuning in these instruments ; but, when accomplished singers are accompanied either by piano or organ, the want of harmony between the voice and these instruments is apparent. This departure from accuracy is at once brought out when chords are sounded on the piano or organ. The best violinists play the natural scale, as was shown by Helmholtz. He accurately tuned a harmonium, or reed-organ, to the natural scale, and Joachim (yo'a-kini), the eminent violinist, having brought his violin to the pitch corresponding to that of the harmonium, accompanied the latter instrument. It was found that the intervals played by Joachim were those of the natural scale. THE VOCAL ORGANS. 407 QUESTIONS.— Name the three qualities that distinguish sounds. Define Pitch. On what does it depend ? Between what limits of vibration is the ear sensitive to sound ? Explain the sensation produced by vibrations fewer in number than 40 to the second. Give some idea of the limit of audition of acute sounds. State the effect of age on the power of appreciating high notes ; the general effect of shock and mental strain. Prove that the pitch rises with the number of vibrations, drawing a diagram of a simple Siren to illustrate your arguments. Describe the method of determining the pitch of a sound with the siren. On what does the Intensity of a sound depend ? Can the loudness of sounds of the same pitch vary ? How ? What relation exists between intensity and distance ? Between intensity and density of medium ? What can you say of the intensity of sounds on high mountains ? Explain Timbre, and the analogy to color. What is a simple sound ? A composite sound ? Explain the harmonics. Analyze the sound of a piano-string. Do the harmonics exist in the sound of the treble C2 ? How may the number and pitches of the sounds forming any complex sound be determined ? Describe the Resonators of Helmholtz. Of what is the Musical Scale formed ? What ratio forms the natural scale of music ? Reduce the ratios of the vibrations to their simplest expression. How can we obtain all the notes of the octave with the simple siren ? Explain the equal-temperament scale. THE VOCAL ORGANS AND THE HUMAN VOICE. How we Speak and Sing. — The little musical instrument with which we speak and sing is formed of two flexible membranes stretched side by side across a short tubular box placed on the top of the windpipe. This box, the lar'ynx, is made of plates of cartilage, movable on one another, and bound together with muscles and membranes. The top of the windpipe is formed of a large ring of cartilage, called the cricoid (wing-shaped) cartilage. Jointed to this is a broad plate, called the thyroid (shield-shaped) cartilage, which has the form of the letter V. The angle of the V points toward the front of the throat, and is familiarly known as the " Adam's apple." On the back of tho upper edge of the cricoid ring are jointed two small, pointed cartilages, known as the aryt'enoid (funnel-shaped) cartilages. Stretching from them to the inner surface of the thyroid are two yellowish-white elastic membranes, the so-called vocal cords. When the point of the thyroid is not pulled down, these cords are loose, and the breath from the windpipe passes freely between them, and does not make them vibrate (see B, Fig. 293). But, when the peak of the thyroid is pulled down by its muscles, the vocal cords are stretched. At the same time the arytenoid cartilages move nearer A and B, views of the human larynx from above as actually seen by the aid of the instrument called the laryngoscope ; A, in the condition when voice is being produced ; B, at rest, when no voice is produced ; e, epiglottis (foreshortened) ; cv, the vocal cords ; «, elevation caused by the arytenoid cartilages ; Z, root of the tongue. If air from the lungs is now forced through the narrow slit between the cords (called the glottis) they vibrate like the tongue of a reed-pipe, and produce the sounds of the voice. The almost infinite variety of sounds that one can evoke from this instrument is the result of various degrees of stretching (tension) of the vocal cords, combined with the movements of the mouth, lips, and tongue. FALSETTO VOICE. voices are sharper, or higher-pitched, than those of the latter. When a boy reaches the age of fourteen or fifteen, his larynx develops rapidly, the cords lengthen, and his voice "breaks," falling usually an octave in pitch. In exceptional cases, the development of the larynx is checked, so that the adult man is able to sing soprano parts. Some have the power of shortening at will the vibrating parts of the cords, and so producing falsetto notes of different pitch. In such cases, the cords may be brought closer together posteriorly, or both in their posterior and anterior portions, as shown in Fig. 294. Disorders of the Voice. — The production of the simplest tone implies freedom of the vocal cords to approach each other ; and complicated vocal effects involve the action of nearly 100 muscles in producing and driving the current of air, regulating the tension of the cords, and changing the size and form of the oral cavity. Hence the power and quality of the voice are extremely subject to changes. All depressing diseases weaken the voice ; any interference with the perfect or regular approximation of the cords, as in the case of a cold or straining of the voice, causes hoarseness or huskiness ; and certain forms of paralysis and painful affections of the throat, in which the cords can not meet, are marked by aphonia, or complete loss of musical tone. The human voice is also peculiarly susceptible to emotional influences ; hence the hoarseness or tremulous utterance of passion, the speechlessness of fear, etc. Speech is voice modified and modulated by the movements of the lips, the tongue, and the parts of the cavity of the mouth. The oral cavity is made larger or smaller, longer or shorter, and thus, resounding to some lower 01 higher harmonics of the voice, it makes the others feebly heard. All the vowel-sounds are formed by a steady voice, modified by the resonance of the different sizes and shapes given to the cavity of the mouth. The consonants are made by obstructions placed at the beginning or end of the oral sounds, by the movements of the tongue and lips. The lower animals have voice, but are without the power of significant articulate speech. The utterances of the parrot are mechanical, not intelligent. Koenig's Manometric Flames. — Many interesting and instructive experiments with the human voice may be made by means of a simple apparatus invented by Koenig, of Paris. Fig. 295 shows it in a simple form. An upright piece of wood, A, noted also in the corner of the figure, has a hole bored in it by a center-bit. This hole does not pass entirely through the piece of wood, but another and smaller hole is bored in the center of the one just formed. Similar holes are bored in the block B, which has also an- MANOMETRIC FLAMES. other hole bored obliquely into the cavity formed by the center-bit. A piece of very thin paper, gold-beater's skin, or India-rubber, is placed over the large hole of the block A so as to cover it, and is cemented to the block by glue or mucilage. The block B is then placed on A, as shown, and these two pieces of wood are glued together. We have now a box separated into two compartments by the sheet of rubber. Into one of these compartments gas is led by a rubber tube, as shown. This gas issues from the box by the tube D, whose upper end is drawn out into a burner. The gas is lighted at F, and then lowered till it burns with a small bright flame. - Into the other compartment of the box enters a large glass tube, E, to which is attached a rubber tube having at its other end a cone made of cardboard. A flat piece of wood is cut out, as shown at M, and by means of rubber bands two pieces of mirror are fastened to the faces of the board. The upright rod of the mirror is rotated in a conical cavity formed on the block K, which rests on the brick L. When you sing into the cone while the mirror is twirled between the fingers, the flame viewed in the mirror presents the appearance of a band of light with its upper edge cut into teeth like those of a saw. This shows that the flame is vibrated by the action of the voice on the membrane, which divides the box into halves. On one side of the membrane is the flowing gas ; on the other, the air in a state of vibration. When the condensed half of a sound-wave falls on this membrane, the latter is forced into the compartment in which is the gas, and the gas is driven out of the tube D in a short puff, causing the flame suddenly to rise in height. At the next instant the membrane goes in the opposite direction under the action of the rarefied halfwave, and the flame suddenly falls. When the mirror is revolved and no sound-vibrations enter the cone, the reflection from the mirror draws the light of the flame into a brilliant band or ribbon ; but on singing into the cone, you will see the flame vibrate, and the upper edge of the band become serrated. Each tooth shows a vibration of the membrane, which thus faithfully gives an account of its motions on the flame reflected from the mirror. As you change the note of your voice, the appearance of the flame will change. If the mirror is revolved regularly, then, as the pitch of the voice rises, the number of teeth increases in the band of light. Sing the song o on the note, and you get Fig. 296 C. This is evidently not the figure that a simple sound gives. It is formed of alternating large and small mirror when we sing the English vowel a on the note / of the octave above the treble. This sound is made up of two simple vibrations combined. One of these alone would make the long tongues of flame ; but with this simple vibration exists another of three times its frequency — that is, the latter is the third harmonic of the lower sound. QUESTIONS.— Describe in detail the human larynx with its appendages, and the action of the vocal cords in producing the Voice. What causes a high-pitched voice ? A low-pitched voice ? Explain the difference between the voice of a woman and that of a man ; the production of falsetto tones. Illustrate the sensibility of the voice to disease, strain, and emotional influences. What is Speech ? Explain the production of vowels and consonants. The Vocal Cords and the Larynx, with the cavities of the mouth and nose, form, as has been shown, an instrument similar to a reed-organ pipe. A vox-humana pipe can be made to articulate some simple words like papa' and mamma!. These experiments are made by forming a cavity between the two hands, and then opening and shutting this cavity at the proper times, while the open mouth of the pipe is between the hands. Reed-pipes, with a little practice, can also be made to say " Amen," " Go away," and several other simple combinations. Faber's Talking-Machine. — The experiments with the reed-organ pipe show the principles followed by Faber, of Vienna, in the construction of his celebrated talkingmachine. A vibrating ivory reed, of variable pitch, forms the vocal cords. There is a mouth-cavity, whose shape and size can be rapidly changed by depressing the keys on a key-board. Rubber tongue and lips make the consonants. A little windmill turning in the throat rolls the r, and a tube is attached to the nose of the machine when it is desired to produce the nasal sounds of French. Edison's Talking Phonograph. — From this description it is evident that Faber worked at the source of articulate sound, and built up an artificial organ of speech, whose parts as nearly as possible perform the same functions as corresponding organs in our vocal apparatus. Faber attacked the problem on its anatomical side. Edison, however, considering the vibrations as already produced, it matters not how, makes them impress themselves on a sheet of metallic foil or on a hard wax composition, and then reproduces from these impressions the sonorous vibrations which caused them. Figs. 297 and 298 will render intelligible the construction of Edison's invention. A cylinder, C, turns on an axle which passes through the two standards A and B. On one end of this axle is the crank D ; on the other, the heavy fly-wheel E. The portion of the axle to the right of the cylinder has a screw-thread cut on it, which, working on a nut in A, causes the cylinder to move laterally when the crank is turned. On the surface of the cylinder is scored a screw-thread similar to that on its axle. F (shown in detail in Fig. 298) holds a plate of iron about ^ of an inch thick. This plate can be moved toward and from the cylinder by pushing on or pulling out the lever H Of, which turns in a horizontal plane about the pin I. The under surface of this thin iron plate (A, Fig. 298) presses against short pieces of rubber tubing, which lie between the plate and a spring attached to E. The end of this spring carries a rounded steel point, P, which, when brought up to the cylinder by the motion of the handle, H, enters slightly into the grooves scored on the cylinder, C. The distance of the point P from the cylinder is regulated by a set-screw, S, against which abuts the lever H G. Over the iron plate A is a disk of vulcanite, B B, with a hole in its center. The under side of this disk nearly touches the plate A. Its upper surface is cut into a shallow, funnel-shaped cavity, leading to the opening in its center. sheet of foil, so that if we turn the cylinder it will make a depressed line or furrow where the foil covers it. The mouth is now placed close to the opening in the vulcanite disk, B B, and the metal plate is talked to while the cylinder is revolved with a uniform motion. The thin iron plate vibrates to the voice and the point P indents the foil, impressing on it the varying numbers, amplitudes, etc., of the vibrations. If the vibrations given to the plate A are those of simple sounds, then they are of a uniform regular character, and the point P indents the foil with regular undulating depressions. If the vibrations are those of complex and irregular sounds (like the sounds of the voice in speaking), then the depressions made on the foil are similarly complex and irregular. Thus the yielding and inelastic foil receives and retains the mechanical impressions of these vibrations. A permanent impression having been thus made, we now obtain from these impressions the aerial vibrations which made them in the following manner : The plate A with its point P is moved away from the cylinder by pulling toward the experimenter the lever H G. Then the motion of the cylinder is reversed till there is brought opposite to the point P the beginning of the impressions it made on the foil. The point attached to the plate A is now brought up to the cylinder, and a large cone of paper or of tin is placed against B B to re-enforce the sound. The crank is then steadily turned. The elevations and depressions made by the point P now pass under this point, and in doing so cause it and the iron plate to make over again the precise vibrations which animated them under the action of the voice. The consequence of this is, that the iron plate gives out the vibrations which previously fell upon it, and thus repeats what was said to it in the very tones of the speaker. Persons traveling in distant lands may now, after " speaking into " their phonographs, send the cylinders of wax composition by mail to their friends, who have simply to revolve these cylinders in similar instruments, and listen to the messages they utter. The phonograph is also used by physicians to record the sounds made in coughing. Peculiar coughs characterize different diseases and different stages of the same malady, and these may now be preserved for comparison and leisurely study. chine which reproduces speech and musical tones with all their delicate shades of expression and modulation. He has in this later machine replaced the metallic foil by a cylinder of a hard wax composition, which can be placed on and taken off the machine. This cylinder is turned by an electric motor, regulated by a governor. For the iron plate which received and reproduced the vibrations, he has substituted one of thin glass ; and instead of the point which indented the tin-foil, he now uses a delicate chisel which cuts out the wax on the cylinder, and thus engraves in the wax the most delicate variations of vibratory motion of the thin glass plate. Harmony and Discord. — If flashes of light succeeding one another a few times in a second enter the eye, a painful sensation is caused ; but, if the number of flashes a second is increased till they exceed 10 or 20, a steady light is perceived and the disagreeable sensation vanishes. The reason of this is, that the impression of the flash of light remains as light on the eye about -fa of a second, and, if another flash follows before the impression of the former has disappeared, the two sensations blend and we have a continuous sensation. On this fact Helmholtz constructed his theory of harmony and discord, by showing that the same effect was produced by what we may call flashes or beats of sound (see page 386). He did not, it is true, determine experimentally the number of beats in a second required by various sounds to blend into a continuous sensation. This was first done by Prof. Mayer, who found out the facts by experiments with disks perforated with various sizes and numbers of holes, which admitted and shut off the sound, and thus produced flashes of sound on the ear. Thus it was found that the duration of the sensation of a sound depends on the pitch of the sound, and that the higher the pitch the less the duration of the sonorous sen- Column N gives the names of the notes corresponding to the vibrations a second in column V. The c' in this series is that used by physicists generally, and gives 256 vibrations. In column B is presented the smallest number of beats a second which the corresponding sound must make with another in order that the two may be in harmony, or, as it is generally stated, may make with the other the nearest consonant interval. If 47 beats a second of c', for example, blend, then the sensation of each of these beats remains on the ear ^ of a second. In column D are given these durations in fractions of a second. As these fractions are the lengths of time that the sensation lingers in the ear after the vibrations of the air near the drum-skin have ceased, they are very properly called the durations of the residual sonorous sensations. Observe, in the table, that this duration becomes shorter as the pitch of the sound rises. Thus, while the residual sensation of C is ^ of a second, that of c"' is only ^. The discord produced by two sounds, Helmholtz explains by the fact that the sounds produce beats, which do not blend because they are too few in a second; but, if the two sounds be gradually made to differ more and more in pitch, the beats increase in number and at last blend into a smooth, continuous sensation. He defines discord as a discontinuous sensation, harmony as a continuous sensation. The beats given by two sounds in a second are equal to the difference of their numbers of vibrations in a second. Thus, if we had one sound given by 256 vibrations a second and the other by 320, their difference is 54. Our table shows that, for 256 vibrations, only 47 are required to blend into a continuous sensation, so these two sounds are in harmony. This is well known, for they are the sounds of c and of E, and form the major third. . Suppose we had two sounds falling at the same time on the ear, one of 256 the other of 303 vibrations a second. The difference of these numbers is 47. Referring to the table, we see that the sound of 256 vibrations remains on the ear ^V of a second ; therefore these sounds just form a harmonious combination — the minor third of the treble. Assume that the c of 256 vibrations and the d of 238 vibrations a second are heard simultaneously ; the difference here is 22, but 47 vibrations are required to produce a continuous sensation. Hence these two sounds form a discord. They are separated only by a tone on the piano. Thus, through the whole musical scale we can, from the table given, determine beforehand what notes, when sounded together, will make harmony, and what notes will give discord. QUESTIONS.— Describe Faber's talking-machine ; Edison's Phonograph, illustrating the principle by diagram. What use has been made of the phonograph ? On what analogy did Helmholtz construct his theory of Harmony and Discord ? Explain discord. Give Helmholtz's definition of harmony and discord. How may we determine what notes, when sounded together, will make harmony ? The steth'oscope, employed by physicians in making physical examinations, consists of two tubes, terminating at one end in a flange which is applied to the chest, and with ivory tips at the opposite extremities of the tubes for insertion in the ears. Explain the principle by which healthy and abnormal sounds in the heart and lungs are made known in an exaggerated form to the examiner. Does confusion arise from our hearing sounds with two ears ? It is believed that two ears possibly correct the errors of each other ; they certainly help us to determine the place whence sounds proceed. Why are musical instruments provided with sounding-boards ? So as to increase the area of the vibrating surface, and thus gain in intensity. If the intensity be increased in this way, remember that the duration of the sound is diminished MAGNETISM. NATURAL AND ARTIFICIAL MAGNETS. Lodestones. — It was known to the ancients that a certain black mineral possessed the power of attracting small pieces of iron or steel. This mineral was an ore of iron, called by the Greeks magnes, from Magnesia, the name of a city iii Asia Minor, near which it was procured. Specimens of the same magnetic iron are now found in various parts of the earth and are known as natural magnets, sometimes lodestones (leading -stones), because when freely suspended they tend to point north and south. The pupil may prove this fact by hanging a piece of lodestone in a stirrup of copper wire. After oscillating for a few seconds, it will come to rest with its length in a northerly and southerly direction. rubbed with a natural magnet, it will acquire the properties NOTE.— With the apparatus shown above, the fundamental principles of magnetism may be illustrated. Nos. 1 and 7 are horseshoe-magnets ; No. 2 shows bar-magnets ; No. 3, a piece of steel watch-spring ; No. 4 is a magnetic needle mounted on stand ; No. 5 is a sifter for iron-filings (made cheaply by removing the bottom from a tin box and soldering on a piece of fine wire gauze in its place) ; No. 6 is a pocket compass ; and No. 8, a piece of lodestone. This outfit may be obtained of any dealer in electrical apparatus. of the latter and become itself a magnet, attracting ironfilings, needles, etc. The power of communicating magnetism from one body to another may be applied indefinitely ; the same magnet may be used for this purpose many times without losing its strength. imparted is called an Artificial Magnet. Natural magnets are now seldom used except as curiosities, because artificial magnets are cheaper, and it is much easier to make them of convenient forms than is possible in the case of a brittle mineral like lodestone. Varieties of Artificial Magnets. — There are several kinds of artificial magnets, called from their shape BarMagnets, Horseshoe-Magnets, and Magnetic Needles (see figure, page 419). It is possible, however, to magnetize a piece of steel of any other shape, and for special purposes magnets have been made in the form of spheres, disks, and rings. A magnet is usually furnished with a piece of soft iron of proper size and form to develop and preserve its full attractive power, and this is called the Armature, or keeper. Magnetic needles are light magnetic bars, generally lozenge-shaped, delicately pivoted, as in the pocket compass, or suspended by a strand of silk. The needle is sometimes placed horizontally on a floating cork for purposes of experiment. Compound Mag-nets. — Let the pupil tie a number of knitting-needles in a bundle and then rub them thoroughly with a FIG. SOO.-COMPOUND magnet in one direction. On testing the HORSESHOE-MAG- needles separately, it will be found that only those which were on the outside of the bundle have become strongly magnetized. This is because the magnetic effect does not penetrate very far from the outer surface. MAGNETIC ATTRACTION. 421 therefore, to make a large powerful magnet, a number of steel bars are magnetized separately and then riveted together. A magnet made in this way is called a Compound Magnet, and may have either the bar or horseshoe form. Attraction. — If a small iron nail be brought in contact with a natural or artificial magnet, it will be attracted by the latter and may be lifted from the table. This power of attracting iron is the most important and characteristic property of the magnet, and almost all the useful applications, as well as the scientific experiments of magnetism, are based upon it. Iron is not the only- metal attracted by the magnet \ cobalt and nickel are similarly influenced. The pupil may experiment with a bar-magnet on different substances — paper, leaves, sawdust, steel-filings, pieces of lead, copper, and zinc — and thus ascertain for himself what bodies are magnetic. also attracted by them in turn. Although the attractive power of lodestone was known in antiquity, it was regarded merely as an interesting phenomenon and never utilized. Pliny informs us that Ptolemy Philadelphus proposed to build a temple at Alexandria, the ceiling of which was to be of lodestone, that its attraction might hold an iron statue of his queen Ar-sin'-o-e suspended in the air. Death prevented Ptolemy from carrying out his design ; but St. Augustine, at a later day, mentions a statue thus actually held in suspension in the temple of Se-ra'-pis at Alexandria. Attraction through Bodies. — A magnet attracts a nail through a board, book, or plate of glass, just as if nothing intervened. Through an iron plate, however, the attraction is reduced or entirely checked. through, air. The iron plate, however, takes up the magnetic effect, being itself attracted, and so prevents the force from passing through and reaching the nail. not essential to the action of a magnet. Polarity. — A nail is attracted much more forcibly by the ends of a magnet than by the middle portion. A bar-magnet dipped in iron-filings becomes thickly coated at its extremities ; few filings adhere to the middle of the bar. This shows that the greater part of the magnetic effect is concentrated at the two ends, and they are called the poles of the magnet. tance inward. From these poles the attractive power decreases almost uniformly toward the center, where it is reduced to nothing. The line of disappearance is called the neutral line of the magnet. convenient point. North and South Poles. — One particular pole of the needle, if suspended by a string, or pivoted as in the ordinary pocket compass, will always be found to turn toward the north. This is therefore called the north-seeking, or north pole ; the other, the south-seeking or south pole. The poles of a magnet are usually distinguished by the letters N and S ; but sometimes the north pole has merely a line filed across it, and is called the marked pole. It is also Considerable confusion exists in regard to the names of the magnetic poles. In this country and in England the poles are generally distinguished as stated above ; but the French call the pole which points north a south pole, while the Chinese attach the fleur-de-lis to the south instead of the north pole. The north pole is sometimes painted red and the south pole blue. QUESTIONS.— State what you know of the history of Magnetism. What is the origin of the word ? What is lodestone ? Describe its properties. Into what two classes are magnets divided ? Why are artificial magnets preferable to natural stones ? How are artificial magnets made ? Name several varieties of artificial magnets. What is an armature ? Explain the principle of the compound magnet. Mention the chief properties of magnetism. Describe the phenomena of attraction. Is iron the only substance attracted by a magnet ? What use was made of magnetism in antiquity ? What effect on attraction has a board or piece of glass interposed between the magnet and the magnetic body ? Does attraction take place in a vacuum ? How can you prove your answer ? What would be the probable effect on a watch if a bar-magnet were brought near it ? The balance-wheel would be attracted, and the watch would stop. (Watches are now manufactured whose entire escapement is made of metals which are by nature insensible to magnetism.) Explain polarity. Account for the appearance of a magnet dipped in iron-filings. Where does the greatest attractive force reside in a magnet ? Where the least ? In what different ways are the north and south poles of a magnet distinguished ? Can you think of other amusing experiments with the magnet ? (Suggestions : Floating objects may be cut out of cork and pieces of steel imbedded in them. A well magnetized steel bar concealed in a piece of a bamboo cane will serve as a magic magnetic wand, with which floating figures may be attracted and repelled, etc.) Can you contrive a way of causing a threaded needle to appear suspended in the air ? LAWS AND PRINCIPLES OF MAGNETISM. Law of Attraction and Repulsion. — If a compass and a magnet be brought close together, the two north poles and the two south poles will repel each other ; but the southseeking pole of the magnet will attract the north-seeking magnets. A number of magnetized sewing-needles are fixed in small corks, so that they will float in a basin of water with their points down. The needles arrange themselves in symmetrical groups, according to their number, Fig. 305. If a bar-magnet be presented, one pole will be found to attract the floating needles, the other to disperse them. (Study Fig. 304.) The opposite action of different poles may be further illustrated by suspending a steel key from the north pole of a bar-magnet, and moving along the latter a second magnet of the same size, with the con- INSEPARABILITY OF POLES. 425 by supporting them, with their poles in opposite directions, on the same pivot, in the same vertical plane. An instrument thus constructed is called an Astatic Needle (not standing in a north and south line) ; it does not seek the north pole, but remains in the position in which it is placed. The Second Law of magnetism is as follows : The force exerted between two magnetic poles, whether attraction or repulsion, is directly proportional to the product of their strengths, and inversely proportional to the square of the distance between them. The experimental proof of this law is measurably difficult, because it requires instruments for accurately measuring the amount of the force and the distance ; but a few trials will convince any observer that the force between two poles two inches apart is only about one quarter as great as at a distance of one inch. The Two Poles Inseparable. — A piece of watchspring, even though magnetized by rubbing it with only one pole of a magnet, always acquires and this is the case however small the pieces may be. Both parts of this experiment demonstrate the principle that a magnet can not be made with one pole only. Two poles, one south and the other north, must always exist together, and must also be of equal total strength, though this strength may be differently distributed. The absolute inseparability of the two poles is one of the most inherent and unchangeable facts in magnetism. It is explained on the principle that the power of a magnet resides in its molecules, whose north poles are all turned in one direction and the south poles in another, so that the poles of magnetic elements intermediate between the extremities of the magnet neutralize one another. The magnetic force is thus free only at the + and — ends of the magnet. action of a magnet on other bodies is called Induction. The polarity induced is such that an unlike pole is created in the end of the magnetic substance nearest the inducing pole of the magnet, and a like pole in the opposite end, as shown in the figure. The interposition of a sheet of paper or glass, the hand, or any non-magnetic substance, between N and S, will not interfere with the inducing power of the magnet. Induction accounts for the attraction of a piece of soft iron. An unlike pole is first induced in the iron and then attracted ; and this effect is greater than the repulsion of the like pole at the opposite end, on account of the distance of the latter. Hence the general result is attraction. Soft iron armatures become magnets by induction, and then by induction react upon their magnets, thus strengthening the power of the magnets themselves. The rolling armature, shown in Fig. 309 attached to a U-shaped magnet, is attracted with such force that when the magnet is held in a vertical position and the armature descends, instead of falling off it turns the poles and is carried by its momentum some distance up the opposite side. The Magnetic Chain. — A number of pieces or rings of iron may be suspended from a magnet in the form of a chain, each individual in the series becoming by induction a temporary magnet. Carpet-tacks may be used in making the experiment. If the tack in contact with the magnet be once lose their magnetism and fall to the ground. It will be found that a given magnet will support a certain number of tacks in the form of a chain ; but when a second magnet is placed beneath the chain, so that its south pole is under the north pole of the original magnet, the magnetic power in the poles of the several tacks will be increased by induction, and the chain may be lengthened by the addition of other tacks. ficial magnets- By simPle ru^bing with a piece of lodestone, in the direction of the line joining its poles,' a steel bar may be magnetized. The method by single touch consists in rubbing the bar with the pole of a permanent magnet, care being taken that the strokes are delivered in the same direction. In magnetization by double touch, a bar of hard steel is placed horizontally, and the opposite poles of two strong magnets are then applied to the peated several times ; the bar is then turned, and the other side treated similarly. It will now be found to be strongly magnetized. Ketentivity. — A hard steel bar, magnetized as described in the last experiment, retains a large part of the magnetism. Soft iron treated in the same manner retains little or no magnetism. Hence we say that hard steel has great magnetic retentivity, or coercive force, and soft iron very little. For this reason, when we wish a magnet to retain its power permanently, we make it of hard steel. Lifting Power. — A horseshoe-magnet will lift a load three or four times as great as a bar-magnet of the same weight (see Fig. 312). This is because both poles of the former act instead of one; and, furthermore, each pole increases the effect of the other by induction. This lifting power is the simplest test of the strength of a magnet. A good magnet weighing one pound should lift twenty pounds. Small magnets will carry relatively more weight than large ones. Newton is related to have worn in his ring a piece that can be exerted. MAGNET Preservation of Magnets. — Magnets may in various ways be weakened or entirely lose their power. The following precautions should therefore be observed in order to keep them in good condition : 1. Do not allow a horseshoe-magnet to remain for any length of time without its armature. Bar-magnets are generally weak because they are not usually provided with keepers. Hence they should be kept either in pairs, with the unlike poles together, or else with bars of soft iron laid alongside to act as keepers. posite kind of magnetism. 3. Do not leave a magnet with its south-seeking pole pointing north, because in this position its polarity may be weakened or even reversed by the magnetism of the earth. will disturb the magnetic arrangement of the molecules. 5. Do not heat a magnet, as heat perceptibly weakens it. The most powerful magnet becomes absolutely demagnetized at a red heat, and remains so after cooling. Magnetize a piece of knitting-needle, then raise it to a red heat, and you will find that it has entirely lost its magnetism. by gently tapping the card or glass. These curves may be made permanent by coating the glass with paraffine or varnish and allowing it to harden before the filings are sifted upon it. After the curves are formed, the paraffine or varnish is softened by heating the plate over a spirit-lamp, or warming it in an oven, and the filings sinking into the film, the curves become fixed when the plate cools. Plates thus made may be used as lantern-slides. The curves described above indicate the direction and intensity of the magnetic force, and from them we derive the idea of lines of force. It should be remembered, however, that lines of force do not really exist, as the actual forces them- net, which space is called the Magnetic Field. The difference between the curves produced by unlike and like poles is shown in Fig. 314. An inspection of the lines of force greatly assists the mind in conceiving how attraction takes place in the first case, and repulsion in the second. Each particle of iron is made a magnet by induction and places its longest diameter in the line of force that passes through it ; and along each line of force a magnetic chain is formed in accordance with principles already explained. Nearly fill one of your test-tubes with iron-filings and then stroke it several times with a powerful magnet. The particles of iron will be seen to set themselves in the direction of their lengths. QUESTIONS.— State the law of Attraction and Repulsion. By what experiments can you illustrate it ? Give the details of Prof. Mayer's experiments with floating magnets. If you lay a bar-magnet on a table with its N pole projecting over the edge, and allow an iron nail to cling to its under side, state and explain what will occur when the S pole of a second magnet is brought over and near the N pole of the first. Describe the astatic needle. What is the second law of magnetism ? Its experimental proof ? Account for the fact that each piece of a magnet has its own poles. Explain Magnetic Induction. How does it account for the attraction of iron ? How, for the strengthening effect of the armature ? Describe the rolling armature ; the magnetic chain ; different methods of making artificial magnets. How would you magnetize a sewingneedle so that the point shall be a north-seeking pole ? What is Retentivity ? Suppose that two rods are handed you, one of iron and the other of steel ; also, a compass-needle and a bar-magnet. Describe experiments whereby you can ascertain which is the iron rod. Compare the lifting power of horseshoe and bar magnets. What methods are suggested for preserving the strength of magnets ? Give reasons in each case. What are lines of force ? Describe the magnetic field. If two long iron wires are suspended from the same pole of a magnet, will they hang parallel ? Why ? The Earth a Great Magnet. — The direction assumed by a magnetized needle is called the Magnetic Meridian. The fact that the needle places itself in the magnetic meridian shows that the earth acts as if it contained a great magnet, some of whose lines of force pass along the ground, while others lie entirely within the earth itself. DECLINATION AND DIP. 431 temporarily magnetized by induction when pointed toward the magnetic pole of the earth, as it is when brought near the pole of a magnet; if struck a blow in the direction of its length when so pointed, it remains permanently magnetized. (Let the pupil make these experiments.) Magnetic Pole of the Earth. — The magnetic needle does not generally point exactly toward the true north. If we carefully compare the direction in which the compassneedle points with the true north line, determined by the north star, we shall find that the two do not in most localities correspond. This shows that the magnetic pole of the earth, toward which the needle points, is not situated at the same place as the geographical pole. A negative magnetic pole, however, must be in the neighborhood of the geographical north pole in order to attract the + P°le of the needle. The angle between a true north and south line and the direction of the needle is called the Declination of the Compass. It amounts to twenty degrees, or even more in FlG 315._DECLINATION. some localities ; while, in the absence of local disturbance, there is no declination at places on a line with the true and the magnetic pole. Declination is subject to variations extending through long periods of years. At London, where magnetic observations have been made since 1580, the declination was in that year IV 17' E. ; in 1657, it had become reduced to nothing, and the compass-needle pointed to the true north. In 1816, it reached its greatest value of 24° 30' W. In 1888, it was only 17° 40' W. Magnetic Dip.— If a needle be balanced so as to be horizontal when suspended by a thread, and then be magnetized, it will not only place itself in the vertical plane of the magnetic meridian, but will point downward at places in the northern hemisphere. The angle at which it is inclined to the horizon is called the Dip or Inclination of the needle, and is due to the fact that the earth is round, and the magnetic pole is there- low such a line. This is illustrated in Fig. 316, in which the line A B represents the true axis of the earth, P the magnetic pole, N S a dippingneedle, pointing at the pole, and C D a horizontal line through the center of the needle. The angle of the earth. Useful Applications of Magnetism. — Permanent magnetism has few practical applications. Magnetism when produced by electric currents (see page 506), is much more powerful and more conveniently applied. Almost the only use made of the permanent magnet is in the Mariner's Compass. This consists of one or more magnetic needles attached to the lower face of a circular card, delicately pivoted, and generally immersed in a liquid so as to decrease the pressure upon the pivot. The circumference of the card is divided into degrees, and also into thirty-two " points of the compass." It is supported in such a manner that the card may always be horizontal, notwithstanding the motion of the vessel. The needles remain in the magnetic meridian, with which a ship's course may readily be compared. The Mariner's Compass was, according to some authorities, invented in China, and made known to Europeans through the instrumentality of the Mohammedan Arabs. The first mention of the use of the magnetic needle in Christian Europe occurs in a curious Provengal poem, written in 1190. Early accounts of the instrument describe it as a simple iron needle magnetized and placed on a pivot, or floated on a cork in a vessel of water, in either case free to the constant hammering during the process of building, causes a serious deviation of the compass, for which allowance has to be made in determining the true direction. the sand with which it occurs. The surgeon sometimes has recourse to the magnet to remove from the eye particles of steel or iron so situated as to render their extraction with ordinary instruments difficult, if not impossible. To determine the presence of steel in any of the tissues, a powerful magnet is held for fifteen minutes on the injured part, thus magnetizing the impacted fragments. Their exact location may then be ascertained by the dip of a delicately suspended needle. Sewing-needles, accidentally forced into the flesh, have been brought within reach by the persistent action of strong magnets. QUESTIONS.— What is the Magnetic Meridian ? The behavior of the compassneedle proves what in regard to the earth ? If you were required to make a model illustrating the magnetic properties of the earth by putting a bar-magnet inside a ball of clay, show by a sketch how you would place the magnet, and explain how the magnetic properties of the model would correspond with those of the earth. Explain Declination ; Dip. To what variations is declination subject ? Describe the Mariner's Compass. Relate what is known of its history. How is it affected by the plates of iron ships ? How are such plates magnetized ? What then has to be made in determining true direction ? For what purpose has the magnet been utilized by the mineralogist ? By the surgeon ? which a magnet supports. Of overloading a magnet. Why does not a freely floating needle move bodily toward the north magnetic pole ? Because the forces that have brought it into the magnetic meridian are then equal, opposite, and in the same line. If a horseshoe-magnet be placed near a compass-needle, it will move the needle a little way round ; but if a piece of soft iron be laid across the poles of the magnet, the needle will move back toward its natural position. Explain this. Illustrate the variations to which Declination is subject. What is a line of no variation ? A line along which the declination does not vary. Columbus discovered such a line east of the Azores (see page 8, Appletons1 Physical Geography). Aware of the change in the direction of the needle, with a change of place, it seemed to him as if he were indeed " entering a new world " in which the very laws of Nature were at fault. It has often been attempted to make magnetic "perpetual-motion machines." The usual plan has been to attach a number of pieces of iron to the rim of a wheel revolving near the poles of a magnet, and to place between the magnet and the wheel a magnetic screen, covering the half of the wheel below the magnet. In this way, the pieces of iron on the upper side of the wheel would be drawn toward the magnet ; but it was supposed they would pass behind the screen upon reaching the point in their path nearest the magnet, and would then cease to be attracted. Hence they would freely move away from the magnet on the lower side of the wheel. Thus there is apparently quite a strong tendency for the wheel to keep on revolving in one direction perpetually, or until the machine wears out. There is, of course, a fallacy in this, as in all other "perpetual-motion machines1' (turn to page 148). What is it? We have learned that attraction takes place through all non-magnetic substances almost equally well ; therefore, there is no known screen or shield for magnetism except iron, or some other magnetic material. But such a screen takes up the lines of force itself, and would therefore weaken the attraction of the magnet for the upper pieces of iron on the wheel. Even if a perfect magnetic shield were found, a machine of this kind would not work, because the magnetic lines of force would curve around behind the shield (see page 429) and hold the lower pieces of iron back exactly as much as the upper pieces are drawn forward, and hence the wheel would stand still. Electricity and Heat compared. — When we are subjected to variations of temperature, as near a furnace or a load of ice, we experience sensations and observe phenomena which we attribute to an agent called Heat. Neighboring bodies at times also differ from one another in a manner which produces other phenomena, and these we refer to an agent known as Electricity. The phenomena of electricity were first observed in the clouds as thunder NOTE.— In the illustration above are shown a typical electrical machine (3), condenser (2), and discharger (4), with a gravity-cell (1), the principle of action in the case of each generator of electricity being explained in the following chapter. A class provided with these articles (furnished by all prominent dealers in electrical instruments), and such other simple apparatus as can easily be improvised in accordance with directions given in the text, will be enabled to perform the fundamental experiments in electricity. It is recommended that there be added a glass rod and a rod of shellac or vulcanite for excitation, a cat's skin as an exciter, a dozen pith-balls, a few gold leaves, and a yard or two of copper wire. Cheaper electric machines may be purchased or constructed by the ingenious pupil ; but the Toepler-Holtz (shown above) is by far the most satisfactory, giving brilliant discharges and working under all atmospheric conditions. 436 ELECTRICITY. and lightning. They were produced artificially by rubbing amber (in Greek, electron)^ perhaps 600 years B. c. ; but Benjamin Franklin first showed that the electricity of amber was identical with that of the clouds. Differences of temperature are continually obliterated by the transmission of heat from hot bodies to neighboring cooler ones. Electrical differences are more quickly equalized, hence their phenomena are less frequently noticed in Nature, unless instrumental methods of observation are used. The savage sees little of heat except in the fluctuations of the weather and in his camp-fire. In civilized life, we meet it in furnace and forge, in our gas-flames, in the bearings of machinery, in chemical reactions, and in thousands of cases where it is used in the arts. commonly known through similar applications of electricity. Potential. — When neighboring bodies differ in such a way that electrical phenomena are observed in the region between them, the bodies are said to be at different potentials. Two clouds which differ sufficiently in potential will be connected by a flash of lightning. If a stick of sealingwax or a cake of resin be rubbed with a piece of flannel or a cat's skin, the two bodies will assume different potentials. They are said to be electrified, as a body of high temperature is said to be heated. An Electrified Body brought near to any other uncharged body of different potential will attract it. If the second body is easily movable, it will be drawn toward the first. Small pieces of paper, pith-balls, a soap-bubble, a toy balloon, or a light pendulum of any material, will, under such circumstances, be attracted ; and a water-jet from a siphon or hydrant will be deflected into a curve instead of falling in a vertical line (see Fig. 319). If a hard rubber pen-holder or large glass tube be vigorously rubbed with a experiments just described. In a dark room, flashes of light may be seen during the rubbing of the two bodies, accompanied with a crackling sound ; and by presenting the knuckle to the electrified body, faint sparks are sometimes observed. A peculiar odor is perceived when such sparks are produced; in the case of lightning which strikes the earth, it is always noticed by persons in the vicinity. This odor is that of ozone, a colorless gas formed from the oxygen of the air. The face when brought near the excited body feels as if a cobweb were in contact with it — a sensation really due to air-currents which are repelled from the body against the face. FIG. 319.— DEFLECTION OF WATER-JET. Attractions and Repulsions. — If a pith-ball hung on a silk fiber is allowed to touch the attracting body, it will, after a few moments, be repelled, as shown in Fig. 320. If the ball be followed up by the electrified body, it will be continually repelled (see page 53). Grasp the pith-ball in the hand. The electricity will be electrified body. Hang a small glass tube in a wire stirrup, the ends of which are tipped with globules of solder, and suspend the whole on a silk fiber, as shown in Fig. 322. Another glass tube which has been excited by friction with silk will attract either end. Allow the tubes to come in contact ; repulsion will not follow. If, however, a metal rod be substituted for the swinging glass tube, either end will be attracted ; but if contact is allowed to take place, the metal rod will finally be repelled. The end which was not touched will also be repelled. Coat a glass rod with an alcoholic solution of shellac, ignite the shellac, and while the tube is hot cover it with tinfoil. It will now behave like the metal rod. WIRE STIRRUP. Conduction of Electricity. — Apparently the electricity is communicated from the attracting to the suspended body. If the suspended body is metallic or has a metallic coating, the electricity is quickly diffused over the whole surface ; but, in order to electrify the glass tube, every part of it must be brought in contact with the electrified body. The metal is said to conduct the electricity. Bodies that transmit electricity freely, like metals, living plants and animals, and water, are known as Conductors ; those that do not, as silk, glass, feathers, hard rubber, and air, are called Non-conductors or Insulators. Electrify a stick of sealing-wax by rubbing it with flannel, and present it to a suspended stick of sealing-wax which has been similarly treated. The sticks will repel each other. Either may be suspended in the wire stirrup, and the other may then be presented to it. The pith-ball, when unelectrified, will be attracted either by the glass rod or the stick of sealing-wax. Electrify it by allowing it to come in contact with either. That body (for example, the glass rod) will then repel it. The other body (in this case the sealing-wax) will then attract it. CONDUCTION OF ELECTRICITY. 439 port, so that they hang in contact with each other. Then electrify them by contact with the excited glass rod. They will immediately fly apart (see Fig. 323). Bring the glass rod up under the two balls, and they will be repelled more widely. The flannel behaves like the glass rod, and repels when the sealing-wax attracts. In a similar way it may be shown that when any two unlike bodies are rubbed together they both become electrified, and that when one will attract the other will repel a third electrified body. In some cases it is necessary to insulate the bodies on supports of glass or hard rubber, to prevent the escape of the electricity. This is the case with flannel and silk, which become slightly moist from the hand ; also with a metal tube, which must be provided with a glass handle. Why? The resulting force is zero. Positive and Negative Electricity. — If the electricity of the two bodies is added together, the bodies become ^electrified. These charges of electricity behave like equal positive and negative quantities. On this account, these electricities are called positive and negative electricities. No reason is known for calling one of them positive rather than the other. The electricity of glass when rubbed with silk is called positive, and that of resin or sealing-wax negative. A body charged with -felectricity is said to have a + potential, while a body negatively charged has a — potential. what as heat and cold. In a room where all objects have the same temperature, two bodies rubbed together become heated, in most cases unequally. The phenomena of heat would resemble those of electricity if the temperature of one of the bodies was raised and that of the other diminished. To carry out the analogy, if the two bodies had originally the temperature of the hand, one would grow cool and the other warm by friction. If left in contact, the bodies would become wwheated again, as two electrified bodies become wwelectrified under similar conditions. tric charges of opposite signs attract each other. 2. The force with which each of two charges attracts or repels the other, is directly proportional to the product of the two quantities of electricity, and inversely proportional to the square of the distance between them. The Unit Quantity of Electricity is the quantity which will attract an equal quantity of opposite sign at a distance of 1 cm., with a force of one dyne (see page 90). Suppose a unit quantity to be placed on a small sphere at A (Fig. 324), and an equal quantity on a sphere B, the distance between the centers of the spheres being one centimetre. The spheres would be pulled together with a force of one dyne. Two spheres at B would each attract A with the same force. If the two charges at B were on attract two units at B with a force of two dynes. Two units at A would each attract the two units at B with a force twice as great as that exerted by one unit. The attraction of two units at A upon two units at B would therefore be four dynes, which is in all these cases the product of the two quantities. Similarly, m units at A would attract m' units at B with a force of m m' dynes. By doubling the distance, the force becomes one fourth as great. At three times the distance, it is one ninth as great, etc. These two laws have been proved by experiment with very great precision. QUESTIONS.— What is the derivation of the term Electricity ? Can you discern any relation between electricity and heat? When were the phenomena of electricity first known ? How are differences of temperature obliterated ? How, electrical differences ? Explain Potential. When the potential of bodies differs, what must take place ? Explain the most noticeable property of an electrified body. What simple experiments can you suggest to illustrate it ? What is ozone, and how is it produced ? Describe and explain the sensation when the face is brought near an excited body. State the law of electric Attraction and Repulsion. How may it be illustrated with suspended pith-balls ? With swinging glass tubes and metal rods ? Explain what is meant by a Conductor ; by a Non-conductor ; by positive and negative electricity. Suppose rods of glass, iron, sealing-wax, and copper, to be rubbed with a silk handkerchief ; which will attract pieces of paper ? The pieces of paper attracted by the electrified rod are repelled after they touch it. Why ? To what extent is the relation between positive and negative electricity analogous to that between heat and cold ? Define the unit quantity of electricity ? METHODS OF ELECTRIFICATION. The Electroscope. — The attractions and repulsions of electrified bodies are studied by means of the electroscope. A very simple form of this instrument is shown in Fig. 325. It consists of a clean flask provided with a rubber stopper, through which passes a tube of hard rubber. Within this tube is a rod made of stiff copper wire. Attached to the lower end of the rod are two small gold leaves, which hang side by side. Soldered to the upper end of the rod is a brass or tin plate one or two which a wire may be hooked. The vessel must be closed while warm, dampness being fatal to all electrical experiments. Hence, such instruments are sometimes dried artificially by introducing calcium chloride, a compound which absorbs the moisture of the air. electrification has disappeared. If the wire be replaced with a silk thread or a glass tube, no effect will be produced when A is touched with the excited body ; but the leaves will diverge if the latter be brought in contact with the electroscope disk. This shows that a silk thread or glass rod does not conduct electricity. If the thread be wet, it behaves like a metal wire, but conducts more and more imperfectly as it dries. Insulation. — A body like A, mounted wholly on nonconductors, is said to be insulated. A piece of metal held in the hand can not apparently be electrified, because the electricity is conducted away through the body. Stroke the ball A with a cat's skin while it is connected with the electroscope by a conductor. Stand on an insulating stool, consisting of a dry pine board supported upon four tumblers or four small cakes of parafnne. Touch the you are well insulated. If tumblers are used, they may have to be warmed, or perhaps exchanged for others, as some glass is not a good insulator. In touching the knob, you cause the charge on the knob and leaves to diffuse itself in part over your body. Provide two insulating stools, and let a person standing on one stroke the hand of a companion on the other with a cat's skin. Both persons will become electrified, the first positively and the other negatively. This distribution of the charges can be tested by the electroscope. If the instrument has been charged by contact with an excited glass rod rubbed with silk, the hand of a positively charged person brought near the electroscope disk will cause the leaves to diverge more widely. To test the negative charge on the other person, the electroscope should be charged by contact with hard rubber or gutta-percha rubbed with flannel or a cat's skin. The leaves will again be repelled more widely. If the electroscope is electrified, a body oppositely charged, on being presented, will cause the leaves to fall together; but, as an unelectrified body would cause the leaves to behave in the same manner, the repulsion of the leaves is always the safe test. hung on silk cords. Bring an electrified body, C, near one of the balls, as shown. Now move A away, while C remains in position. Both A and B will be found to be electrified. The opposite electricity appears to have been attracted to the nearer ball, and the like electricity repelled to the more distant one. If the electricity of the inducing body C is reversed in sign, the charges on A and B will be reversed likewise. by induction. Discharge A and B by touching them, and again bring C to the position shown in Fig. 327. The two bodies aro again charged. Next remove C, and afterward test A and B. They will be found neutral. While the bodies are all in the position shown in Fig. 327, touch either A or B with the hand. A feeble spark will be felt. Remove the hand, and the two bodies A and B will seem neutral in the presence of C. If C is removed, the two bodies will be found charged with electricity the opposite of that on C. When the body was touched by the hand, the repelled electricity escaped to the ground, through the person of the experimenter. The attracted charge was held or bound by the opposite charge on C. When the body C was removed, the bound charge on A and B became a free charge. It would then go to the earth if received by the hand. Bring an electrified body — a glass rod, for instance — near the instrument. The negative electricity will be attracted to the plate, and the positive electricity will be repelled to the leaves, which will diverge. Touch the plate, and the leaves will collapse as the repelled electricity upon them escapes. Now remove the inducing-rod. The leaves again diverge as the attracted electricity is diffused over them. There remains a free charge .on the electroscope leaves, having the opposite sign from that contained on the inducing body. If the inducing-rod be now brought up toward the electroscope, the leaves will again collapse. Any positively-charged body will produce the same effect ; but a negatively-electrified body will cause the leaves to diverge more widely, as more electricity is repelled to the leaves. THE ELECTROPHORUS. melted sealing-wax, making the surface of the layer as level as possible. To the center of a somewhat smaller metal disk, fasten a handle of glass. Avoid sharp edges on the disk^* QUESTIONS.— Describe the gold-leaf Electroscope. In what way is dampness excluded ? How may it be charged by contact ? How positively ? How negatively ? When is a body said to be insulated ? Describe an insulating stool ; an experiment by which two persons on insulating stools may be charged with positive and negative electricity. Why can you not depend on the collapse of the gold leaves in determining the electrical state of a body brought near the electroscope ? Explain fully electrification by Induction. How may you charge the electroscope by induction ? If it is charged negatively and an insulated brass ball is brought near, what is the electrical condition of the ball when the leaves slightly collapse ? When they slightly diverge ? Then remove the glass rod. On bringing the balls near to each other again, a spark will pass between them. Give the reason. Explain the action of the Electrophorus. Place a pith-ball on a metal plate provided with a glass handle ; then place the plate on a cake of resin which has been rubbed with a cat's skin. When the plate is touched with the finger and then lifted by the handle, the pith-ball jumps off. Why ? What must you do in order to get a succession of sparks from the electrophorus ? ELECTRICAL MACHINES AND CONDENSERS. Electricity confined to the Surface. — No electricity exists on the inner surface of a conducting shell. In Fig. 329 an insulated cylinder of wire gauze is represented as electrified and as repelling the pithballs hung on the outside. Those on the inside are not affected. A metal ball hung on a silk cord, if brought in contact with the outside of the electrified wire screen, receives a charge, as is shown by its effect on the electroscope. If the wire screen is made large enough to admit an experimenter with the electroscope, it is found that, by bringing the testing-ball in contact with the inside of the screen, no charge is obtained. If the ball, charged by contact with the outer surface, is carried inside and placed in contact with the inner surface of the screen, its whole charge goes FlG- SSQ.-INSULATED CYLIN,, , „ DER OF WIRE GAUZE, Electricity may be attracted to the inner surface of a hollow ball by a charge upon an insulated body within the cavity (see Fig. 343). If the body makes contact inside the cavity, the charge escapes to the surface. The principle explained above is practically applied in a variety of so-called electrical machines, contrivances for developing and collecting large quantities of statical electricity, or electricity produced by friction. INDUCTION MACHINE. One form is shown in Fig. 330. Here I I are inductors, supposed to be at different potentials. They have the form of hemi-cylindrical shells. The hollow metal balls a and a', called carriers, are mounted on the ends of radial insulating rods, and revolve around a vertical axis. As the balls sweep through the concave inductors they are momentarily placed in metallic contact with one another by means of springs mounted on rods, b b, which are connected by a wire. The repelled charges of opposite sign cancel each other by being added together on these rods. As the carriers move on to the positions a a, each will have a free charge, opposite in sign from that on the inductor which it has just left. The balls, a #, next pass inside of the collectors, C C, where they touch a metal spring, by means of which their charges are wholly carried to the external surfaces of C C. The carriers, when in the position a' #', are therefore neutral, and the same operation is repeated. Each collector is connected by means of a wire, w, with the inductor toward which the carrier moves. There will always be such a difference of potential between the two sets of conductors in this machine that, when the carriers are turned, the electrification will begin and will increase until the leakage in a second equals the amount added. If, several hours after you have brushed your clothing, you should stand nearer to one side of the ma* chine than to the other, this will be enough to cause it to excite when turned. When the machine is to be used for producing sparks, each rod of the universal discharger (see page 460) must be connected with one of the wires, w w. In Sir William Thomson's Water-dropping Electric Machine, two jets of water, J, from any common source, H, fall through two hollow cylindrical inductors, ] (see Fig. 331). The jets are controlled by screw- clamps, so that they break into section, Fig. 332. There is always sufficient difference of potential between the two inductors to start the machine when the water begins to drop. In the inductor which is negative with respect to the other, the jet forms a conductor, the nearest end of which is positively electrified by induction. The negative charge is repelled up the jet, and the drops fall away posi- ACTION OF POINTS. tively electrified into a funnel on the inside of the collector below. Here they lose their whole charge, which goes to the external surface. The positively-charged collector is connected with the inductor on the other support by means of a wire, w. This inductor acts precisely like its companion, a change of sign only being required for the explanation. The drops of water constitute the carriers. On each side, the drops are falling away from an inductor which attracts them, and toward a collector which repels them. They also repel one another ; hence a large part of them fall outside of the collectors. A difference of potential of about 7,000 volts (see page 493) can easily be maintained by this device, as long as the water-supply is kept up. The supporting columns may be made from heavy glass tubing. The inductors should be about an inch and a half in diameter, and three or four inches in length. The whole apparatus can be made by the pupil with the aid of a tinner, and affords a most instructive illustration of many of the phenomena of electricity. forcibly the gold leaves of the electroscope. If the conductor have the form shown in Fig. 334, a testing sphere applied to the pointed extremity will acquire a greater charge than at the rounded end, the least charge being acquired when contact is made at the side. The density of the charge is said to be greatest at the ends. If the electrified body terminates in a sharp point, as in Figs. 335 and 336, the density is so great that the electricity escapes from the point very rapidly and the body becomes neutral. In the dark, the point appears tipped with a luminous glow called a brush. Should the flame of a candle be held in front of the point, it will be blown aside, because the particles of air in the immediate vicinity of the point, having become electrified by contact, are repelled by the highly charged point with such velocity as to drive back the flame in turn. The mutual repulsion between points free to move and the electrified air which flows from them, is illustrated by the electric whirl or flier, consisting of metallic wires branching out from a common center, and with pointed ends bent in the same direction. If the whirl is balanced on a rod attached to the conductor of an electric machine in action, it will revolve in a direction opposite to that in which the bent wires point. Why? When the room is darkened, the points become luminous, and a circle of fire seems to be formed. from or into pointed bodies. This action of points is utilized in some forms of electrical machines, now to be described. The conductors of all electrical machines terminate in rounded ends or edges, in order to avoid leakage. They should be kept free from dust, as brush discharges are likely to stream even from dust-particles. The Toepler-Holtz Machine, a celebrated generator of electricity both for medical purposes and physical use (see No. 3, page 435), is really a combination of two induction-machines like that described on page 447. On the back of a stationary glass plate (Fig. 338) are two cards, X X, which act as inductors ; and on a smaller revolving glass plate, in front of the former, are pasted a series of carriers, a a', made of tin-foil, each of which has in its center a metal button or stud designed to serve as a contact. As the carriers are ahout to leave the inductors, the two on the same diameter are touched by flexible metal springs or wire brushes fixed to the stationary diagonal rod #, which crosses the moving plate. The repelled charges on the carriers are thereby simultaneously removed, exactly as is done by the rods I I in Fig. 330. Passing to the opposite inductor, each carrier touches a second metal brush in contact with that inductor through rods C C. The bound charge which each carrier held at the previous contact with the diagonal rod b, while in front of the other inductor, is now in part communicated to the inductor having a like charge, through the collectors C C. The function of these carriers is to restore the charges which leak away from the two inductor-cards, the operation being ex- replenished with positive, the other with negative, electricity. As the inductors become charged, they act inductively on the revolving plate, electricity of the like sign being repelled to the surface* farthest from the card inductor. The combs C' are also acted upon inductively, and electricity of the opposite sign from that on the card is attracted, and streams from the points of the combs in a brush discharge upon the plate. When, for instance, any part of the glass in its revolution arrives at the comb C' on the right, the negativelycharged glass around the collector is rendered neutral by an attracted brush discharge from the comb, which leaves a repelled or free negative charge on the conductor. These conductors terminate in knobs, K K, between which a discharge of sparks is thus kept up while the glass plate is in revolution. In the second half of a revolution, the operations are all repeated, the signs of the charges being reversed. The Friction Electric Machine, the oldest form, but far inferior to the modern induction-machines as a producer of electricity, is a simple contrivance for rubbing glass and silk or leather together, and collecting the electricity generated. One form consists of a circular plate of glass, A (see Fig. 339), which may be revolved between cushions, D, coated with an amalgam (usually composed of zinc, tin, and mercury, mixed with grease). When the plate is revolved, the lower part becomes positively electrified. The electricity is collected by the comb F and carried to the prime conductor P, which is mounted on a glass column or fixed, insulated, to the stand of the machine. The clamp at the same time receives an equal negative charge, which is communicated to a second insulated conductor, N. The silk apron, S, in a measure prevents leakage. Connect P and N by a wire. They will both remain neutral, or at the same potential as the earth. Insulate them from the earth and from each other, and N will become negatively charged, P positively. In other words, the potential of N sinks below, while the potential of P rises above, that of the earth. The difference of potential is dependent on the materials rubbed together. A spark can be drawn from either conductor by any person standing on the floor. Connect either P or N with a gas or water pipe, or a lightning-rod having a good earth connection. Even a chain lying on the floor will serve the purpose. This is called " grounding " the conductor. Much longer sparks can now be drawn from the other insulated conductor, but none can be obtained from the grounded conductor. If N has been grounded, its potential has been raised to that of the earth ; but the potential of the positive conductor has been similarly raised, since the difference in potential has not been changed. The difference of potential between the earth and the insulated conductor is therefore increased. Sparks of the same length may be drawn from each conductor, if both are insulated, and a person, standing on an insulating stool, touch either and present his knuckle to the other. A person on an insulating stool, having once touched the conductor, receiving a spark as he does so, may again touch it without receiving a spark. He is already charged to the potential of the conductor, and the electricity can not leak away. A person on the floor may draw a spark from him when thus charged. NOTE.— In another form of the friction-machine a glass cylinder is used instead of a circular plate. Cylinders of glass, amalgam, etc.. may be purchased at slight cost from instrument-dealers, and the pupil may easily construct a simple friction-machine for himself. signed. A common condenser is the Leyden (li'den) jar,* which may be used with all the forms of electrical machines so far described, glass vessel coated within and without, for about two thirds of its height, with tin-foil, put on with flour-paste. Through a cork or wooden cover closing the mouth, passes a metal rod, which terminates above in a ball (why?), and from which a chain hangs in contact with the inner lining of the jar. vals, the length of which increases with the width of the gap between the knobs, and with the size or number of the jars. The electricity appears to accumulate until the jars are charged, and then breaks through the air with a sound like the crack of a whip. Immediately after the spark has passed, the whole machine is virtually discharged, as may be seen by suddenly stopping the revolving plates when the spark passes. One or more jars may be used with the Holtz machine, by connecting all their inside coatings with one another and with one side of the machine, while the outside coatings are connected with the other. The connecting wires should have a globule of solder upon their ends, in order to prevent leakage. The jars should all be insulated. Action of the Leyden-jar. — If two metal sheets, about two feet in diameter, are hung up in parallel on silk cords, they will act as a condenser. Two sheets of zinc, such as are put under stoves, will answer very well if the edges and corners are smoothed. It is necessary to suspend each piece on two cords, in order to keep them in position. The sheets may be connected by means of a fine wire ing to it attached. It will be found that, with the same speed of rotation, the sparks will come less frequently. The metal plates will be attracted together unless held apart by silk cords or other insulators. If the distance between the plates is doubled, the sparks will pass twice as rapidly between the knobs of the Holtz machine. Increasing the size of the plates, or placing them nearer together, increases the interval between the sparks. It is also said to increase the capacity of the condenser. The greater the capacity of the condenser, the longer the time required for it to become knobs when placed a fixed distance apart. The reason for the greater capacity of one of the plates, when near the other, is due to the attraction between the two charges of opposite sign upon the plates. This attraction is shown by the motion of the plates toward each other. Disconnect the plates from the machine, and touch them alternately. Only a feeble charge will pass to the hand at contact. After many such alternate contacts, if the plates are touched simultaneously, a smart shock will be felt. When only one plate is connected with the ground through the body, the electricity on it can not escape, because of the attraction of the electricity on the other plate. Another Form of Condenser, for experimental purposes, is shown in Fig. 343. It is simply a hollow spherical conductor, with an opening cut in the top. An opening in the side will serve to admit a copper wire covered with rubber, or a knittingneedle coated with sealing-wax, to be used as a charger. Charge the inner ball by means of the electrophorus or either conductor of the electrical machine, and remove the charging-wire. Suppose this charge to be positive. Then a negative charge will be attracted to the inside of the outer shell, while an equal positive charge will be repelled to the outer surface. Lift out the inner sphere without touching the outer shell. The latter will be found unelectrified, showing that the two charges are equal. Replace the charged sphere. The outer sphere will now appear electrified again, and will affect the gold leaves of the electroscope if the testing-sphere connected with it be brought near. SHIELDING EFFECT OF CONDUCTING SHELLS. 457 will escape, but the two bound charges will still remain. They exert equal and opposite effects on the electroscope. If the silk fiber now be broken, so as to make contact within, the whole system will instantly become neutral. This proves that the induced charge on the outer sphere is equal to the inducing charge on the inner sphere. If the spheres are neutral, and a charge is communicated to the outer shell, no charge will be induced on the inner shell. The whole charge will remain on the outer surface of the outer shell. Act inductively upon the two spheres, one of which incloses the other, as was done on the bodies A and B, in Fig. 327. The attracted electricity will be found on the outer surface of the outer shell, nearest the inducing body, while the repelled charge will be on the side farthest from the inducing body, and also on the outer surface. No electricity can be found on the inner ball, or anywhere in the interior cavity. shielded from all electrical influence from without. This is best shown by setting a screen made of common wire gauze over the electroscope, the latter resting upon a metal sheet. Sparks from the electric machine may be sent through the wire netting, and electrified bodies may be moved about outside of the screen, without in the least degree affecting the gold leaves. If the screen and electroscope rest upon the poorly-conducting table instead of the metal sheet, the leaves are at once affected. A powder-house inclosed wholly in sheetiron, the floor included, would be safe against lightning. Suppose electricity to be added to a body, A (Fig. 345), until its potential is raised to unity, that of the earth being always assumed to be zero. Now, suppose electricity added also to B until no spark would pass if A and B were momentarily connected by a fine insulated wire. Then A and B are said to be at the same potential. Suppose a body, C, equal to B in size but surrounded by a grounded metallic shell, S, is also charged until no spark passes when C and A are similarly connected. The bodies A, B, and C, have then all the same potential. It is found that it takes more electricity to charge C than B. The effect of the shell has been to increase the capacity of the inner body. The capacity increases as the radial distance between ball and shell diminishes. A toy balloon, coated with soot or graphite powder to make it con ducting, may be loaded to equilibrium. If electrified, it will then rise. The electrical forces make the balloon slightly larger. QUESTIONS.— Prove that electricity is confined to the outer surface of bodies. How may it be attracted to the inner surface of a hollow ball ? What are Electric Machines ? Describe an induction-machine in which the inductors are semi-cylindrical shells ; Sir William Thomson's water-dropping machine. What can you say of the action of points ? Define an electric brush. What happens when the flame of a candle is brought near a charged point ? Explain St. Elmo's fire. How is this action of points utilized in electric machines? State the effect of smooth and rough surfaces on the escape of electricity. Describe minutely the Toepler-Holtz Machine, referring to the illustration on page 451. Compare its action with that of the electrophorus. Describe the plate electric machine. In this machine the conductor is of rounded shape at all parts except where it comes nearest to the glass plate. Here it is provided with sharp projecting points. Explain this. Why will not a plate machine work well in damp weather ? If a silver tea-pot be insulated and electrified, and you touch it in different places with a penny fastened to the end of a stick of sealing-wax, what part of the pot will give the greatest and what part the least quantity of electricity to the penny ? How may you decide with the help of the electroscope ? What are Electrical Condensers ? Describe a Leyden-jar, and the method of charging it by means of electric machines. Illustrate its action in the case of two sheets of zinc. Prove that the induced charge on an outer spherical con ductor is equal to the inducing charge on an inner sphere. Explain the screening effect of a metallic shell or wire cylinder. Under what conditions would a powder-house be safe from lightning ? What is meant by the capacity of a body for heat ? For electricity ? THE ELECTRICAL DISCHARGE AND ITS EFFECTS. Dischargers. — In discharging several Leyden-jars connected so as to act as one, it is necessary to use some form of discharger to avoid a shock, for even a slight shock might cause the death of a person affected with heart-disease.* Hand-dischargers are jointed conductors provided with glass or rubber handles (see No. 4, page 435). In the universal discharger (Fig. 347), the two conductors are supported on glass columns, to which they are hinged so that * An interesting incident is related in connection with the experiments that led to the invention of the Leyden-jar. Prof. Van Musschenbroek (mus'Tcenbrddk), of Leyden, observing that excited bodies soon lose their electricity in the air, determined to see whether he could not collect and insulate the electricity in a vessel of non-conducting glass, so that it might be kept locked up, as it were, ready for use. Accordingly, he introduced a wire from the conductor of an electric machine into a bottle filled with water. After the machine had been working some time, an attendant, holding the bottle in one hand, attempted to withdraw the wire with the other, when he, of course, received a shock, so unexpected and so unlike anything he had ever felt before, that it filled him with consternation. Van Musschenbroek himself subsequently took a similar shock, which he described in a letter. He says that he felt himself struck in his arms, shoulders, and breast, so that he lost his breath, and it was two days before he recovered from the effects of the blow and the fright. He would not, he adds, take a second shock for the whole kingdom of France. ment is to be made. Effects of the Electric Spark — The effect of the discharge from any given jar or combination of jars depends on the nature of the body through which the discharge takes place. Bad conductors are shattered. Good conductors, if sufficiently large, are not apparently affected. All bodies are heated, so that a fine metal wire may become warm or may even fuse. Place a piece of dry sole-leather or a book between the knobs of the Holtz machine, and a hole may be made in it by the spark. Thin glass may be pierced in a similar way. This shows that the medium between the knobs is in a condition of stress, which may produce a rupture of the intervening body. Some idea of the force exerted may be obtained by pushing a punch through the leather or book. tumbler with the freshly broken end of a round file, moistened with a paste made of camphor-gum and spirits of turpentine. Let the tumbler rest on a sheet of tin-foil, in contact with a metal rod which passes up through it and ends in a sharp point in contact with the glass. Support an insulated rod above, terminating in a point exactly on the opposite side of the glass, which should be washed clean with soap and dried before a fire. A little oil may be poured on its upper face to keep moisture away. For a single jar, the glass must be very thin. If the spark passes around the glass, it is useless to repeat the experiment with the same plate. Plates of glass 2J inches thick have been pierced by sparks from a powerful induction-coil (see page 518). The Discharge in Rarefied Gases. — In the Geissler tube, platinum wires are sealed through the extremities into chambers, which communicate with each other through a tube of glass bent into various fanciful shapes. A spark passing from one wire to the other must traverse this bent tube. If the gas within is at atmospheric pressure, the spark will pass around the entire tube rather than through it. If the gas is pumped out, electricity will begin to flash through the tube when the terminal wires are in connection with the knobs of the Holtz machine. As the exhaustion proceeds, the electricity will finally pass in a continuous, flickering, noiseless discharge, revealed by a beautiful glow of light when the experiment is made in a dark room. If the exhaustion is made more complete, the discharge is less brilliant, and finally will cease altogether. In the highest attainable vacuum, no spark will pass. At a certain pressure the discharge takes place most easily ; the insulating power of the air is least. The tubes are sealed at this pressure. A nearly perfect vacuum thus implies high insulation ; a partial vacuum is a good conductor. The Discharge in Air — Lightning. — When the terminals of the Holtz machine have Leyden-jars attached, the electricity accumulates in the jars, and the electrical stress between the knobs increases, until finally the air ruptures, as does the glass plate. Against the pressure of the atmosphere, a long rarefaction similar to that of the Geissler tube forms between the knobs, through which the whole charge of the jars passes. This is why the jars and machine are almost wholly discharged just after the spark has passed. It is as if the knobs had been momentarily connected by a fairly good conductor. Along the line of the discharge, the air-particles are thrown into a state of intense vibration— they become extremely hot. They also give off a light, which yields a spectrum characteristic of the gas as well as of the terminals between which the spark passes. This shows that some of the metal composing the terminals is vaporized. * The pressure of the atmosphere quickly closes the rarefaction with a sound, which in large sparks like lightning is called a crash. The slight discharge of a Leyden-jar sounds like the crack of a whip, which is also due to the closing up of a hole in the air. The Lightning-Flash. — The thunder-cloud and the earth constitute a huge condenser. The cloud is usually positively charged, and the opposite or negative electricity is induced upon the surface of the earth. If the charges accumulate sufficiently, a spark will pass in a flash of lightning, illustrated in the accompanying photographs. It will be seen that the path of lightning is not zigzag in shape, as popularly supposed. In one of the pictures is apparent the beautiful branching effect often secured on sensitive plates. Protection against Lightning. — There can be no doubt of the value of a properly constructed lightning-rod. Before the ships of the English navy were armed with con- ductors, frightful disasters from lightning were not uncommon. They ceased with the introduction of the copper strips which Sir W. Snow Harris designed for attachment to the masts. The lightning-rod is intended to create a line of least resistance, along which the discharge must take place without damage. Lightning-rods should rise in the air as high as chimneys, for otherwise the soot of the chimneys may lead the discharge into the house. The rods should not usually he higher than the highest points to be protected, as it is better not to attract the lightning, but to have it strike away from the house entirely. The region protected by a rod is approximately a cone, whose height is the rod and whose base has a radius equal to the height of the rod. A lightning-rod should be without joints ; or if jointed, the lengths should lap several inches and be tightly wound with copper wire. The rod should extend into the ground until earth is reached which is always moist. It is well to dig a hole several feet deep, and fill around the rod with powdered coke or charcoal. Two ground connections at opposite ends of the building are much better than one. Thunder. — One end of the path of a lightning-stroke may sometimes be as much as two miles farther from the ear than the other. The passage of the discharge is practically instantaneous ; but as sound travels only at the rate of eleven hundred feet a second, the duration of this thunder will be over nine seconds. The path of the discharge is sometimes through air which is not acoustically homogeneous. The sound from some parts of the path is so refracted, reflected, or quenched by interference, that the thunder is barely heard for a second or more ; then it bursts into a roar as sound from other parts of the path reaches the ear without meeting such obstruction. The roar may at this time also be re-enforced by sound from nearer points of the path, which has been reflected to the ear after having traversed an indirect route. The effect is not unlike the rumble of a distant railway-train out into an open stretch of track. Duration of Light ning-Flashes. — We have shown that the duration of a lightning-flash is about the hundredthousandth part of a second. It seems to be longer than this, because of the persistence of sensations on the retina. Falling rain-drops at night, when illuminated by lightning, seem to be stationary in the air. They do not appreciably move ; even the most rapidly rotating bodies appear to be perfectly still while illuminated. A jet of water will show similar results when illuminated by the spark of a Leyden-jar. In a dimly lighted room, the carriers on the Toepler-Holtz machine show as a hazy ring upon the rapidly revolving plate. When the spark passes between the knobs, they seem sharply defined and stationary. Similar experiments may be made with Newton's disk of colored sectors, or the spokes of a revolving wheel. The Aurora is a luminous appearance believed to be of electrical origin. While it is not yet fully understood, all observations point to the conclusion that it may be referred to electrical discharge in the upper and thinner portions of the atmosphere. Magnetizing Effect of the Spark. — It was early noticed by mariners that a lightning discharge often deranges or reverses the magnetism of the compass-needle, so that the end previously pointing north would point south. Let the spark be led around a coil of metal wire having an unmagnetized steel knitting-needle in its axis. The wire coil must have an insulating coating, in order to keep the spark from breaking across from one turn to the next, and it is better to surround the steel with a glass tube to prevent the possibility of the sparks passing to it. If the + charge of a jar is led around the steel in the direction shown in Fig 350, the left-hand end of the steel will become a north pole and the right-hand end a south pole. The steel has become a. magnet. If you stand facing the end which has become a south pole, you will notice that the + charge has passed around the steel in the same direction as the hands of a clock revolve. This rule is always true. feebler until the oscillation dies away. The two cases of discharge are like a deflected pendulum swinging in a viscid liquid and in air. In the liquid, the pendulum will fall to its position of repose without oscillation ; in air, it comes to rest after many oscillations of diminishing amplitude. Should the experiment be repeated with the steel bar reversed in position, the polarity of the steel will be reversed. The north pole will still be to the left. If, however, the + charge is led around the coil in the opposite direction, the north pole will be to the right hand, in accordance with the rule before given. Another Magnetic Action of the Discharge. — Suppose the two terminals of the Holtz machine to be connected by means of binding screws with a wire wound in a coil around a suspended magnetic needle, consisting of several the spot of light upon the scale. This device is shown in diagram, Fig. 351, where the coil is greatly enlarged ^ while the real instrument is represented in Fig. 352. Such an instrument is called a Galvanometer. The coil is composed of a large number of windings, and is covered with a brass case for protection. The mirror-needle is made sensitive by a larger magnet (n s, Fig. 352), which also points north and south, but has its poles so placed that it tends to turn the suspended needles about, end for end. When the large magnet is slipped down upon its supporting rod until the suspended needle is almost on the point of reversing its position, the latter is then extremely sensitive to the action of any other magnet. If the Holtz machine is now turned, the positive electricity pours from the + knob through the wire of the galvanometer to the — knob. The mirror-needle is deflected and the watch-spring magnets all tend to turn east and west, or into a longitudinal position within the coil. This action is opposed by the unbalanced part of the attraction of the earth, which tends to keep the mirror-magnets in a north and south direction. The mirror comes to rest in an intermediate position, when these two forces balance. If the effect of the earth on the needle were to be wholly balanced by the reverse effect of the bar n s of Fig. 352, the effect of the discharge through the coil would be to turn the mirror-magnets exactly into a longitudinal position. In such experiments the Leyden-jars should all be removed from the Holtz machine in order to avoid the danger of the destruction of the insulation in the coil by a spark. The Electric Current. — When the wheel of the Holtz machine is turned while the knobs are connected with the galvanometer, as in the previous experiment, a continuous discharge pours through the wire, producing a constant deflection of the needle. As soon as the machine is stopped, the discharge ceases. Such a flow of electricity along a wire is called an Electric Current. The current is maintained by means of the work applied to the crank of the machine, in the same way that a current of water can be maintained in a pipe circuit by means of work applied to operate a pump. Other properties of an electrical current will be explained more fully after means for producing stronger currents have been treated. The voltaic battery, described in the following chapter, is simply a machine which by chemical action gives rise to a continuous electric current. QUESTIONS.— Describe a battery of Leyden-jars. How are their outer coatings placed in communication ? How, their knobs ? Why is such a combination called a battery ? On account of its powerful effects. May the discharge be dangerous ? Relate an experience of Prof. Van Musschenbroek. On what does the effect of the electrical spark depend ? How are bad conductors affected ? Describe experiments in which the spark may be made to puncture a book ; a piece of glass. WTiat are Geissler tubes ? Describe the discharge in rarefied gases. Will the spark traverse a vacuum ? Explain the discharge in air and the analogy between it and the discharge in the Geissler tube. State the condition of air-particles along the line of the discharge. When does Lightning occur ? Describe lightning-flashes as illustrated by instantaneous photographs. How may you calculate their distance from you ? For what is the lightning-rod intended ? How are disasters averted through its agency ? What should be the height of the rod ? How much space does it protect ? To what depth should it extend into the ground, and why ? Is it necessary to point lightning-rods ? Account for the duration of thunder ; the sudden crash after a moment of silence. What is the duration of a lightning-flash ? Prove your answer. What places are most dangerous during a thunder-storm ? Why is it safe to be in bed ? Explain the Aurora. Describe the magnetizing effect of the spark on a steel needle. Explain the Mirror Galvanometer ; the action of the curved magnet ; the effect of the passage of electricity through the coil of wire. Define an Electric Current. Can you give a reason for the purity of the air after an electric storm ? (Suggestion : Ozone possesses remarkable chemical activity ; it is a powerful corroder and deodorizer.) EXPERIMENTS IN FRICTIONAL ELECTRICITY. — The pupil may construct the apparatus necessary for the following experiments : ELECTRIC BELLS. — Suspend two toy bells from a frame, and hang a brass button between them. Connect one of the bells with the conductor of a machine, and the other with the ground. When the machine is in action, the button is attracted to the first bell, strikes it, becomes itself charged by the contact, and is repelled till it strikes the second bell. Its positive electricity is thus discharged, and it falls back, to be again attracted and repelled. DANCING IMAGES.— On a metallic plate supported by some conducting substance, place several light figures cut out of pith, paper, or cork, and three or four inches above them suspend another plate from the conductor. As soon as the machine is worked, the figures will dance up and down from one plate to another in a laughable manner. Explain the principle. THE ELECTRIC Kiss. — Attempt to kiss a person on an insulating stool, while he holds a chain connected with the conductor of an electrical machine in action. DIVERGING THREADS.— Tie together at each end a cut skein of twenty linen threads, about ten inches in length. Attach them to a conductor, and when the machine is operated they will assume an oval form. Why ? ELECTRIFIED HAIR.— Fix a heavy copper wire to a doirs head furnished with hair, and insert the wire in one of the holes in the conductor of your machine. When the plate is turned, the hairs will stand grotesquely on end. Draw off the electricity by presenting your knife-blade, and they at once fall. MULTIPLICATION OP THE ELECTRIC SP^TRK.— When the continuity of a conductor is broken, sparks dart from one part of it to another. Paste pieces of tin-foil about one eighth inch apart on a length of glass tube, furnish the tube with tin caps, and place one cap in communication with the conductor and the other with the ground. As the sparks pass, the pattern is rendered luminous. A glass globe may be substituted for the tube. The Voltaic Cell. — If a piece of zinc be dipped in dilute sulphuric acid, the zinc will be attacked by the acid and replace hydrogen in it. The zinc and hydrogen sulphate become hydrogen and zinc sulphate. The hydrogen appears in bubbles on the zinc, and passes off as a gas. At the same time, for each gramme of zinc consumed, a definite amount of heat is evolved ; the liquid becomes warm. liquid, the hydrogen gas all appears on the surface of the copper. After the zinc has been amalgamated with the mercury, it is best not to touch the copper plate to it, as the copper will also amalgamate. Properties of the Voltaic Cell. — The wire which connects the copper and zinc plates of the voltaic cell has many interesting properties so long as it is in contact with them. When examined with delicate instruments, it will be found to be heated. It will magnetize iron, and will deflect a magnetic needle. In short, its properties show that a continuous discharge of electricity is pouring through it, the + discharge being from the copper to the zinc. This may be proved by replacing the wire M with the wire of the galvanometer coil ; the deflection of the needle shows that a current is passing through the coil, and by reversing the connections the needle is deflected in the opposite direction. The discovery that the source of electricity in such a case is the contact of unlike substances was made about 1800 by Alessandro Volta, Professor of Physics at Pavia (pah-ve'ah), and from him electricity produced in this way is called Volta'ic* although identical with that THE VOLTAIC CELL. obtained from electrical machines. Volta's celebrated Pile consisted of a series of pairs of copper and zinc plates, separated from one another by pieces of wet cloth. The whole was insulated, and a wire attached to each end. When the wires were brought together or separated, a spark was produced, and a person taking one of the wires in each hand received a shock. The effects of Voltaic electricity may be familiarly illustratedc Place a piece of zinc under the tongue, and on the tongue a silver coin. As long as the metals do not touch, nothing is perceived ; but as soon as they are brought in contact, the Voltaic circuit is formed, a thrilling sensation is felt in the tongue, and a taste like copperas is perceptible ; if the eyes are closed, a faint flash of light is seen. Here electricity is developed by the chemical action of saliva upon the zinc. Lay a silver dollar on a sheet of zinc, and on the coin place a living snail or angle- worm. No sooner does the creature, in moving about, get partly off the dollar and on the zinc, than it receives a shock and recoils. In this case, it is the slime of the snail or worm that acts chemically on the zinc. Materials used in a Voltaic Cell. — The plates of the voltaic cell may be made of any two metals which are unequally acted upon by the liquid in which they dip, the object being to produce a difference of potential. The liquid may be either pure or acidulated water, or salt solutions of various kinds. The choice of materials is determined by the use which is to be made of the cells, the trouble of keeping the cell in order, and the presence or absence of offensive fumes which may result from the chemical action in the cell. In all forms of battery in practical use, zinc serves as the plate which is to be most acted upon. The other plate is usually of copper, platinum, or carbon, and is not acted upon at all. of metals produces muscular contraction in the hind-legs of a frog (1790). Galvani's experiment is often repeated at the present day. Separate the legs of a frog from the body, skin them, lay a thin curved zinc rod under the nerves of the loin, and touch the muscles of one leg with a similar rod of copper. The instant the rods are brought in contact, the leg will be convulsed. Galvani believed these movements to be caused by the passage of electricity from the nerves to the muficles, through the metal rods whicn served as conductors. A battery may be made of two zinc plates, one of which has been cast and the other hard rolled. Even a difference of temperature between two plates, otherwise precisely alike, will give a feeble electrical current. When the two plates are exactly alike, whether they are acted upon by the liquid or not, no current will result. Local Action upon the Battery-Plate. — Neighboring points upon a plate of commercial zinc are always sufficiently unlike to produce a current between them. One point in the plate may be harder than another near by, or it may be under a different pressure by reason of internal stresses developed in solidification ; or impurities may exist in different degrees at the two points. All these conditions will result in setting up local currents upon the plate, which is thus dissolved without producing electrical action through the connecting wire. When mercury is rubbed over the plate, it dissolves the zinc, obliterating the effects of internal stresses, but does not dissolve such impurities as carbon or iron which float out into the liquid. A clean, homogeneous surface of zinc is thus exposed to the liquid. The zinc does not dissolve in the acid except when the plates of the cell are connected by the wire w, or some conductor other than the liquid in which both are dipped. The current then pours through the connecting wire. Polarization of the Battery-Plate. — After the battery has been in action for a short time, the copper plate becomes covered with a film of hydrogen. The cell is then said to be polarized. While the plate is in this condition, the current is much feebler than when it is clean. This is shown by means of the galvanometer. The deflection of the needle diminishes as the current becomes feebler. The hydrogen can be brushed off the plate by mechanical means, or may be removed by lifting the plate into the air. These methods are not very effective, as the hydrogen immediately reappears on the plate. The most effective way of removing it is by immersing the copper plate in some liquid which will combine chemically with the hydrogen as it appears. The cells next to be described are designed for this purpose. VARIETIES OF CELLS, The Gravity Cell. — In this cell, the copper is placed in a solution of copper sulphate (blue vitriol) in the lower part of the vessel. The zinc is suspended _= — - - — _ per sulphate solution has a higher specific gravity than the zinc sulphate, and this keeps the two liquids separate. An insulated wire, having an exposed end fastened to the copper by a rivet, passes out of the top ing screw attached to the zinc above the liquid. When the hydrogen appears on the copper plate,, surrounded by the copper sulphate solution, it replaces the copper of the copper sulphate. Instead of hydrogen and copper sulphate, we have copper, which is deposited on the copper plate, and hydrogen sulphate (sulphuric acid). As a result, therefore, copper instead of hydrogen is deposited on the copper plate. The sulphuric acid diffuses through the liquid and attacks the zinc, forming zinc sulphate. The zinc is thus continually dissolved. The copper sulphate is also consumed, and is replaced by dropping in a few crystals of the substance whenever the blue color in the lower solution has nearly disappeared. The lighter zinc sulphate solution must occasionally be siphoned off with a rubber tube, and water should be poured in carefully. In a dry room, evaporation at the top of the liquid causes crystals of zinc sulphate to form on the jar just above the liquid. The liquid rises through these crystals by capillary action, and crystals form higher up. Thus the salt moistened with liquid will finally creep over the top of the jar and down upon the shelf and floor. This is prevented by brushing a little raw linseed-oil upon the glass above the liquid. Various forms of the gravity cell are used by thousands in telegraphing. Both the zinc and copper plates are made in various patterns. In the older Daniell cell, the two liquids were separated by a porous jar of earthenware. As copper is rapidly acted upon by nitric acid, Grove substituted platinum. In Fig. 355, P is the platinum sheet, placed in a porous jar containing the acid. The zinc is bent in a U-form around the porous jar. The whole is placed in a jar of glazed earthenware, here shown broken away to reveal the interior parts. The outer jar contains dilute sulphuric acid in contact with the zinc. The Bunsen Cell differs from that of Grove only by the substitution of a stick of carbon, made from gas coke, for the platinum sheet. This cell, when worked through short, heavy wires, gives better results than the gravity cell ; but the liquids must be replaced after a few hours of action, and this occasions trouble and expense. The Bunsen cell also gives off corrosive fumes, due to the decomposition of the nitric acid by the hydrogen (see page 471). A solution of 4 parts of sodium bichromate, 4 of sulphuric acid, and 18 of water, may replace the nitric acid in the Bunsen cell. This solution gives off no fumes. The bichromate salt is dissolved in water, and the sulphuric acid slowly added, while the liquid is stirred.* * Water should never be poured into sulphuric acid ; the heat developed is great enough to vaporize the water explosively, and serious accidents may occur. The acid must be poured slowly into the water ; stir, as you pour, with a glass rod. which stands in one corner of the outer vessel. The porous jar contains the carbon plate packed in fragments of coke and powdered manganese dioxide, which acts in oxidizing the hydrogen-bubbles. The liquid is a solution of ammonium chloride in water. This cell, having small power, is much used in working housebells, telephones, railway-signals, etc., where it is required only occasionally and for a short time. The advantage of the Leclanche cell is, that it may be closed up in a box to prevent evaporation and left for a year without attention. Dip-Batteries. — Various forms of cells have been constructed, which allow the zinc plates to be lifted from the solution when not in actual use. pulling upward upon the rod, the zinc may bs raised. In Fig. 358 all the plates of two cells are attached to a cross-piece which slides upon a vertical rod between the cells. The rod is mounted upon a bed-plate of iron, upon which the cells also rest. The plates are held in position when out of the solutions by means of a gravity latch-piece, which drops into a notch in the vertical rod. One liquid only, the bichromate of potash solution, is used. It yields no noxious fumes, and is in that regard preferable to nitric acid. Hence these cells are much used for table-work. Arrangement of Cells in a Battery. — When the wires leading to a galvanometer are attached to the zinc and carbon plates of a battery cell, instead of to the knobs of the electric machine, as in Fig. 351, the mirror-needle is permanently deflected. This shows that a current of electricity is flowing in the wire. The stronger the current, the greater the angle of deflection of the needle. If it is desired to get a stronger current than is given by one cell, a number of cells may be connected so as to act together. In Fig. 359 four cells are joined, the zinc of each being connected with the carbon or copper of the next. In Fig. 360, the four cells have their zincs all connected by a metal conductor, the coppers or carbons being similarly connected. These main conductors are then connected by wires with the galvanometer. Such cells are said to be connected in multiple or in parallel circuit. When the cells are in multiple, the current from any one cell does not flow through any other cell, but the separate currents are forced out in parallel streams through the conducting wires and galvanometer. The Proper Arrangement of the Cells of a battery depends entirely upon the kind of battery used, and the nature of the external circuit. If it is desired to send a current through a long, thin wire, and one cell gives an insufficient current, other cells must be added in series, as in Fig. 359. The longer and smaller the wire, the greater the number of cells required. If a coil of wire, r (Fig. 359), be connected in the circuit, the current will become feebler. More cells mast be added in series in order to force the same current as before through the circuit. If the circuit is made up of large copper wires, connected with a galvanometer consisting of one turn of large wire, then, if one cell gives an insufficient effect, the added cells should be in multiple. The current is not materially increased by adding cells in series with the short, large conductors of Fig. 360, nor by adding them in multiple with the long fine wires of Fig. 359. It appears that the conducting wires offer a resistance to the passage of the electricity ; that this resistance increases with the length of the conductor, and diminishes as the size of the wire increases. The battery acts in a twofold way. It drives the current through the wire and also serves as a conductor, since the current must flow through the battery. If the battery-plates are small, the effect is to make the resistance great, as is the case with a wire when its section is small. In Fig. 360, if only one cell is acting, its resistance is large as compared with that of the wire conductors. If the three other cells be added in multiple, they will act precisely as one cell of four times the section. The effect is to diminish the battery resistance to one fourth of that of one cell, the battery resistance comprising nearly the whole resistance. The power of the four cells for driving electricity through the wire when thus connected is the same as for one cell, as will be shown later (page 480). In Fig. 359 the resistance of one cell is small compared with that of the long, fine wire. When the three cells are added in line, the battery resistance is made four times as great, since it amounts to an increase in the length of the conductor ; but the battery resistance is still insignificant as compared with that of the wire. The resistance of the whole circuit has not, therefore, been materially changed ; but the power of the battery to drive electricity through resistance is four times as great. Hence an increase of the current results. If, however, water is to be forced through a very large tube, K, as in Fig. 362, little will be gained by adding pumps in series, should one pump like those represented be insufficient. The water - current is throttled in the pump instead of in the pressure which drives the water is not thereby increased. The pumps balance one another. The four pumps simply act as one pump of greater section, but with no greater pressure per square inch. Similarly, in an electric battery, if the current is throttled by high resistance in the conducting wire which it is not feasible to diminish, cells must be added in series to increase the electro-motive force sufficiently to drive the desired current through the resistance. If the current is throttled in the battery, its resistance may be diminished by increasing the sectional area of the battery liquid through which it must flow. This is done by connecting cells in parallel, and an increase in the strength of the current will result. QUESTIONS.— Define an Electric Current. An electric current is a continuous transference of electricity between bodies having a difference of potential. Apply this principle in a description of a Voltaic cell. How can you prove that the current flows from the copper to the zinc ? Why is electricity produced in this way called Voltaic ? Describe Galvani's experiments, and state his theory. Give Volta's correction of this theory. Describe the Voltaic pile. Suggest some familiar illustrations of Voltaic electricity. Enumerate the materials used in the Voltaic cell. Prove that the source of Voltaic electricity is chemical decomposition. What is the cause of local currents, and how do they affect the action of a cell ? State the effect of rubbing mercury on the zinc plate. What is meant by polarization of the plate ? How is it corrected ? Explain, with the aid of sketches, the gravity, Grove, Bunsen, Leclanche, and bichromate cells. Why is the latter preferred for table-work ? Describe the arrangement of cells in a battery in series ; in multiple or parallel. On what does the proper arrangement of the cells depend ? Explain your answer. In what two ways does a battery act ? Compare with the action of pumps differently arranged. If a charged battery is to be kept for some time ready for use, why is it important to take care that the ends of the wires are not connected outside the battery ? To detect the presence of a bullet or piece of metal in the tissues, a probe is used consisting of two pieces of insulated wire attached to small plates of zinc and copper. The copper is placed on one side of the tongue, the zinc on the other, and the wound is probed. State how the surgeon will be made aware of the presence of the metallic body when the tips of the wires touch it. Explain the principle. Sum up the differences you have observed between the current from a Voltaic battery and that from a Holtz machine, as regards intensity, ease of production, heating and magnetic effects, power of chemical decomposition, and impression on the nervous system. Unit of Electrical Resistance. — When electricity flows through any medium or circuit, it meets with resistance. We can always determine how much greater is the resistance offered by any piece of wire than that offered by some standard of resistance. RESISTANCE COILS. sistance of a column of pure mercury having a section of one square millimetre and a length of 106-28 centimetres at a temperature of 0° C. A copper wire having the same section and resistance must have a length of 6,090 centimetres, and a German-silver wire, a length of 485-4 centimetres. Conductors of the same size and having twice these lengths, will have a resistance of two ohms. Thus the resistance is proportional to the lengths. If wires twice as thick are used, the resistance is one half as great. Thus, a copper wire, having a length of twenty feet and a section of two square millimetres, will have the same resistance as a wire of the same material ten feet in length and one square millimetre in section. arranged as shown in Fig. 363. The wire is wound upon a spool, like thread, and is doubled upon itself at the middle, the two halves being wound side by side. The coils do not then become magnets when a current passes through them. current will flow through the bars and plugs, which offer only an insignificant resistance by reason of their large size. If any plug is pulled out, the current must then flow through the coil of wire beneath, whose resistance is thus added to the circuit. 10,000 ohms. Standard Resistances. — Let a standard coil be placed in a water-tight metal box, and the ends of the wire connected with large copper conductors (W, W, Fig. 366), which when in use dip into small dishes of mercury, serving as connections. As the resistance of all substances varies with temperature, these coils are standard at some definite temperature. When in use, the coil is immersed in water, the temperature of which is measured by a thermometer. The increase in resistance for each ohm when heated through 1° C. is for copper wire 00038 ohm ; and for German silver (composed of copper 4 parts, nickel 2 parts, zinc 1 part) the coefficient per ohmdegree C. is 0-00044. Thus 100 ohms of copper at 0° C. become 100 + 100x25x0-0038 = 109-50 ohms at 25° C. be poured into the hole around the pipe. A well into which an iron rod dips may also be used. One plate of the battery, B, is also grounded at G. The other plate is connected with the line at D through a delicate galvanometer, V, and the resistance-box, R, the plugs being all in place. The galvanometer-needle is deflected and its position is noted. The line is then disconnected at D, and the battery wire at C is disconnected and attached to D. Resistances are then introduced by pulling plugs from the box until the needle is again at the same position. The coils within the box form an artificial line, and their resistance is equal to that of the actual line. In the first measurement, the earth is excluded, but it is so large that its resistance is insignificant if good connections are made at the earth plates, Gr and G'. This is learned by measuring two grounded wires upon the same poles between any two stations, as New York and Washington. The distant ends are then disconnected from the ground and connected with each other. The near ends are also disconnected from the ground and connected with binding screws at C and D. The two wires then form a loop from the testing-table in New York to Washington and back. The resistance of the two lines in this measurement is found practically no resistance. In the loop measurement, the two wires are connected into the circuit exactly as the wire coil, W, would be if its extremities were connected at C and D, and the ground and line were disconnected at those points. The resistance of the coil W can evidently be found in the same way. Measurement of Resistance by means of the Differential Galvanometer. — The differential galvanometer consists of two coils, W, of insulated copper wire (Fig. 368). mounted on the ends of two rods which slide with gentle friction through the sides of a box. The ends of the wire forming the coils terminate in four binding screws upon the side of the box. Between the coils, suspended on a fiber of silk, is a small magnetized needle or other suitable magnet. A wire from either end of a battery communicates at A with two branches, one of which connects with S through the plugged resistance-box, the other with S3. The current is then led through the galvanometer coils to the screws S8 and S4, from which wires uniting at B return the current to the other end of the battery. At any point in the battery line between A and B, a key, K, is fixed, by depressing which the circuit is closed. The two coils of the galvanometer are so placed and connected that they tend to deflect the needle 90°. but in opposite directions when the key is closed. If the two branches have equal resistances, each will carry half of the battery current. They may be so adjusted by sliding one of the connecting wires through the binding screw, as at S3. The position of the coils is adjusted by sliding them in or out on the rods. The adjustment is complete when opening and closing the key produces no deflection of the needle. The needle is made more sensitive by means of two bar-magnets, N S, lying on the table parallel to it. If it sometimes points wrongly, the magnets N S may by patient adjustment be made to restore it to its proper position. The sensitiveness of the needle will also be increased by placing the coils nearer together. Now connect the coil r, whose resistance is to be measured, with the branch not containing the resistance-box. The resistance of this coil obstructs the current in that branch, and more than half now flows through the other branch, the galvanometer coil of which has a greater effect than the one in the branch of greater resistance. If plugs are now pulled from the resistance-box until on opening and closing the key the needle is again in balance, the added resistance in the box is equal to that of the coil V. This operation precisely resembles the determination of weights by a lever-balance of equal arms, where the unknown weight is counterpoised by standard weights. Faults on Telegraph Lines and Cables. — When an overland line breaks, its resistance becomes practically infinite. The break is usually located without difficulty by simple inspection, so that electrical methods are unnecessary. In ocean cables it is important to locate the break in order that the cable may be grappled and raised as near as possible to the fault. The resistance of a given cable in a perfect condition is known, being frequently measured. When the cable breaks, it makes a " ground " in the water. If this ground is one third of the way across FAULTS. 487 from the American to the foreign terminus, the resistance from the American side at once drops to one third of that determined by previous measurements, provided the foreign ground connection is broken. In a similar way the fault can be located by measurements from the foreign end, which will show a resistance of two thirds of the whole cable resistance. Sometimes the fault is not complete, but involves merely leakage through a crack in the insulation. The fault itself will then have an appreciable resistance, and the measurement from the American end will locate the break too far away from our shore. Measurement from the foreign end will then locate it too far from the foreign shore, the faultresistance being in each case measured with the fraction of cable. The sum of the two will be greater than the resistance of the perfect cable. The break then lies midway between the two points thus located. Caution in measuring Resistance. — In all cases where the resistance of a coil, as W in Fig. 368, is to be measured, the coil must be far enough from the galvanometer not to deflect the needle directly. Such a coil when traversed by a current becomes an electro-magnet. It is to avoid such trouble that the wires of resistance-coils are doubled on themselves, as was previously explained. QUESTIONS.— Explain Electrical Resistance. What is the Unit of Resistance called ? Compare the resistance of a column of mercury with that of a copper and of a German-silver wire of the same length and section. State the relation between resistance and length of wire ; between resistance and thickness of wire. What are resistance-coils ? How are they connected with batteries ? Describe a resistance-box. What is the effect of temperature on the resistance of substances ? How are standard resistance-coils applied in measuring the resistance of telegraph lines ? Compare the mode of ascertaining unknown resistance in terms of standard coils with a method of finding the weight of a body by the use of the spring-balance. Describe the Differential Galvanometer, and explain its use in the measurement of resistance. Compare its operation with the determination of weight by a lever balance. What effect on its resistance has a break in an overland line ? How are breaks in cables and underground wires located ? Explain what occurs when the fault involves leakage merely. How is the place of leakage found ? Why are the wires of resistance-coils doubled on themselves ? The Unit of Current is called the Ampere (am-pare1). If a current is passed through a solution of copper sulphate (blue vitriol) by means of two copper plates having the form shown in Fig. 353, copper will be deposited on one plate and dissolved from the other. The plate connected with the zinc plate of the battery will receive a deposit of copper. The other plate will, if of pure copper, lose an equal amount. As it usually contains impurities which are in part washed off into the liquid, the loss of this plate is generally a little greater than the gain of the other. A current of how many amperes will therefore deposit one kilogramme an hour ? A current of how many amperes will deposit one pound an hour? If the current is passed through water, the water is also decomposed into its constituent gases, hydrogen and oxygen. The hydrogen is liberated at the plate connected with the zinc plate of the battery, while oxygen forms at the other. These gases may be collected in tubes in the usual manner, and the amounts of gas are found by measuring the volumes (Fig. 369). The water must be slightly acidified in order to make it a good conductor. The plates used for the decomposition of substances are called electrodes. The one attached to the zinc wire is called the negative electrode, or cathode, and the other is the anode. Hydrogen and metallic substances are deposited that of the battery. If the battery is taken out of the circuit, this current is easily shown by the deflection of a galvanometer-needle. The current from the electrodes is always feebler than that from the battery, and when the two are connected the result is the enfeeblement of the battery current by the decomposing cell. The current from the electrodes, due to the chemical action, resists the battery current, which has brought about the chemical action. The polarization of the battery-plates themselves is an action of the same kind. is reversed. If a piece of steel had only a north pole and were acted upon only by the current, the pole would revolve round the wire in any one of the circles in which it might be placed when the current was started. A south pole would turn in the opposite direction. As every piece of steel has both poles, which are urged in opposite directions, the needle sets in the line of force. In Fig. 371, the current passes upward through the wire, and the arrows on the plate indicate the direction in which the north pole points. This direction may be remembered by means of is BENT. Ampere's Rule. — Imagine yourself floating in the current within the wire, with your head in the direction in which the current flows and facing the needle. The north pole of the needle will always be on the left hand. A piece of soft iron lying in this position would be magnetized, with the polarity which a glass plate are no longer concentric circles. Along the axis of the wire a c a', the line of force is a straight line. A north pole placed on the right at a would move to c, then to a', and then on to an infinite distance to the left along this line, if acted upon only by the current. All the other lines are closed curves encircling the wire. The arrows show the position of a magnet-needle. In a galvanometer, the needle is hung at C. The coil is turned so that the needle, N S, is in the plane of the coil. When the current is turned on, the needle sets at such an angle that the forces of the earth and coil balance each other. The Ampere-Meter. — Currents are measured by means of an Ampere-meter, of which one form is illustrated in Fig. 375. A short, lozenge-shaped needle, n s, is mounted on a small shaft, P, as shown in section (Fig. 373). The needle and shaft turn on a jeweled pivot, and are mounted between the poles of two strong curved magnets, M, which give direction to the needle, n s. The current is passed around two coils, C. of large wire, the size of which depends on the magnitude of the currents to be measured. hour, the current must have been 10 amperes. On the permanent scale, reading in amperes, this point should therefore be marked 10. Increase or diminish the current by changing the number of cells or by varying the resistance, and other points of the scale may be similarly determined. THE VOLT. 493 The Tangent Galvanometer, which may also be used to measure strong currents, consists of a coil of wire whose plane is vertical, and coincides with the plane of the magnetic meridian. At the center of the coil is a short magnetic needle, with a pointer attached, which plays around the graduated circle of a compass-box. When no current is passing, the needle points to magnetic north and south. But, when a current is sent through the coil, it tends to deflect the needle at right angles to the coil. The strength of the current to a certain extent determines the amount of this deflection, which is always proportionate to the tangent of the angle of deflection. If the coil be turned 90°, so that the needle stands at right angles to it, and the current is then sent around in the proper direction, it will not affect the needle, which is already where the current tends to place it. QUESTIONS.— What do you mean by the Ampere ? How much copper will one ampere deposit in a second ? How much silver in an hour ? Explain how water may be decomposed by a current. What are electrodes ? Distinguish by name positive and negative electrodes. Describe the relation between electrodes and battery-plates. Which current is feebler— that from electrodes or that from the battery ? When the two are connected, what is the result ? How does the deflection of a magnetic needle furnish a ready method of detecting when and in what direction a current flows ? State Ampere's rule for aiding the memory. Illustrate the application of this rule by holding the wire in various positions, above, below, parallel to the needle, etc. How do iron-filings arrange themselves on a glass plate through which passes a current-carrying wire ? How, when the wire is bent into a circular form ? Describe in detail the Ampere-Meter ; the Tangent Galvanometer. By the Electro-motive Force of a Battery or cell, is meant its power of driving electricity through the resistance of the circuit. It is sometimes called electrical pressure. The unit electro-motive force, or difference of potential, is called the Volt. It is the electrical pressure required to maintain a current of an ampere through a resistance of an ohm. The relation of current, resistance, and potential difference, can be illustrated by a current of water. In Fig. 376, T represents a tank of water, in which the water is maintained at a fixed level by means of a pump, while the tank discharges through a pipe B o. At regular intervals glass tubes, serving as manometers (see page 198), are tapped into the discharge-tube. The height to which the water rises in each tube indicates the pressure. At the mouth of the main tube, the pressure is zero; it B e, is required to force the current through the resistance of the pipe C o. The pressure of the column P h is required to force the same current through the resistance P o. If P o is three times as great as C o, then P h must be three times as great as C 0. From B to o the resistance is represented to be seven times as great as from C to o, and the pressure of B e is also seven times as great as C o. The fall of pressure is the same through each unit of resistance. From A to P it is the difference between columns H and h. This difference in pressure is what is required to maintain the current through the resistance of A P, and it is the same as C 0, or one seventh of B e. If the pipe were half the section, the same pressure B e would deliver only half the current. The pressure line e H h o would, however, remain the same. If the discharge-pipe, on the other hand, were twice as long, the effect would also be to reduce the current to one half. Both of these changes would double the resistance of the dischargepipe. To get the same current as before, the water in the tank would have to be raised to twice the height B e. The fall of pressure for each unit of resistance is thus seen to be always the same for the same current. All these statements are true for a current of electricity. Electrometers arc used for measuring potential or electric pressure. One form of the quadrant electrometer is shown in Fig. 377. Four insulated hollow quadrants of brass have suspended within them a flat hour-glass-shaped needle of aluminum. In Fig. 378 the quadrants are shown come charged, as shown in Fig. 378 ; the needle is repelled by the + quadrants and attracted by those charged—. The angle of deflection is read by abeam of light reflected from a mirror. Adding cells in line, as in Fig. 359, increases the deflection. It increases the charge on the quadrants. It increases their electrical pressure or potential. It makes the + quadrants more strongly posi- tire, and the — quadrants more strongly negative. If the space separating the quadrants is narrow, the pressure difference would become so great, by adding thousands of cells, that the charge would break through the insulation of air between the quadrants, a spark would pass, and the battery would maintain the discharge. We should practically have an electric light. Adding cells in parallel, as in Fig. 360, does not change the potential. When cells are arranged in parallel-series, the deflection depends only on the number of cells in each line, and not upon the number of lines. In Fig. 379, the line represented in Fig. 367 is shown in diagram. If one set of quadrants of the electrometer E be grounded, and the other connected with the line at A, the needle will be strongly deflected. If the contact is made at B, the deflection will be less, and, as the contact slides to the ground at C, the deflection will fall to zero. Contact being made at D, the deflection will be in the opposite direction, but it will again fall to zero at F. The potential falls along the line A C, in the same way that the pressure falls in the pipe (Fig. 376). If a battery of 1,500 Grove cells were connected in the line, it would be fatal for one to stand on the ground and touch the wire at A (Fig. 379). The human body would offer a rather high resistance, but the potential there is so much above that of the ground that a fatal current would be driven through the body. At B the danger would be less, and it would diminish to nothing at C. We have learned that one volt of electric pressure will maintain a current of one ampere through one ohm of resistance. Two volts will be required to maintain the same current through two ohms. R volts will drive an ampere through R ohms. This equation is an algebraic statement of Ohm's law. Expressed in words it is : The number of volts required to maintain a current of C amperes through R ohms is obtained by multiplying the number df units of current by the number of units of resistance. law are found by measurement, the third can be computed. Electro-motive Force of Cells. — In Fig. 376 the pressure of the column of water B e is required to overcome the resistance of the pipe B o. It is evident that the pump itself offers resistance to the passage of the current, and therefore that the total pressure required to drive the current through the entire circuit is really greater than B e. This total pressure corresponds to the electro-motive force of a cell, or the electric pressure required to drive the current through the battery and external circuit. Such electro-motive force depends only on the materials used in the cell, and not at all upon its size. It changes somewhat as the liquids are exhausted during action. If 196 Daniell cells were connected into one line, the electromotive force would be 196 x 1-07 = 209-7 volts. If 107 Grove cells were connected in line, the battery would have an electro-motive force of 107 x 1-93 = 209-7. If these batteries were connected against each other in one circuit, they would balance, and there would be no current in that circuit. In the same way it can be shown that the electro-motive force of a battery is due simply to the cells in line. If 100 cells, all in parallel, be connected with one opposing cell, there will be a balance. The resistance of the battery of 100 cells will be the one hundredth of the resistance of one cell ; but their electro-motive forces are the same. Similarly, two lines of 25 cells each, in parallel, will balance one line of 25 cells when connected in opposition in the same circuit. In the same way any number of pumps, working in parallel, would be balanced by a single pump of the same, kind working against them in the discharge-pipe. Divided Circuits. — When a battery-wire divides into two branches, as in Fig. 380, the current also divides between the two branches as a current of water would divide in a branching pipe. The sum of the two currents in the branches will be equal to the current in the undivided part. The fall of potential from a to b will be the same through the two wires, as the fall in pressure would be the same in the two branches of a tube. The pressure in the branches must be FIG. ^.-DIVIDED BAT- the same at the points where they The currents in the branches are inversely as their resistances. The current will be least in the branch having the greatest resistance. If one branch be broken, its resistance will become infinite, and its current will be zero. If one resistance be practically zero, all the current will flow through it. ized in a resistance-coil which has been plugged out of circuit. The current practically all flows through the plug instead of the coil. The resistance of the plug is practically zero. When the plug is drawn, the resistance of this branch becomes infinite, and the current is driven around the coil. The same result would follow in the case of the pipe, if the short branch A were closed. The current would all flow around B, whose resistance would be introduced into the circuit. Shunted Galvanometers. — When it is desirable to measure a current which exceeds the capacity of a galvanometer, a wire may be connected across the terminals of the galvanometer, and through it any fraction of the current may be deflected. This wire is called a shunt, and the galvanometer is said to be shunted. The galvanometer then measures a known fraction of the total current. If the galvanometer have a resistance of 3-0 ohms and the shunt a resistance of \ of 30 or 033 ohm, then the current in the galvanometer will be -J- of the current in the shunt, or ^ of the total current. QUESTIONS. — Define the electro-motive force of a battery. By what other name is it sometimes known ? Explain its relation to difference of potential. What is the unit electro-motive force, and by what name is it called ? By what analogy may the relation of current, resistance, and potential difference, be illuS' pressure for each unit of resistance is always the same for the same current. Explain the use of the Quadrant Electrometer in measuring electric pressure. Illustrate the instrument by diagram. How might it become an electric light ? Does adding cells in parallel change the potential ? Under what circumstances would it be dangerous to touch the wire of an electric circuit ? Why ? Repeat Ohm's law. State it algebraically. To what is the current directly proportional ? To what, inversely proportional ? Compare the total pressure required to drive a current of water through a pipe with the electro-motive force of a cell. Oil what does this electro-motive force wholly depend ? Explain the balance of opposing batteries ; of 100 cells in parallel and one opposing cell ; of pumps working in parallel and a single opposing pump. Describe the division of a current ; the current in the case of a looped wire ; the passage of water through a divided pipe. What is meant by a shunted galvanometer, and for what is it used ? HEATING EFFECTS OF CURRENTS. Heat developed by Resistance. — A short, thin wire of platinum, iron, or German silver, if placed in the circuit of a large Bunsen, Grove, or bichromate cell, will become red-hot. The remaining part of the circuit should be of short, thick wire. This is a case of the development of heat at a point of high resistance. The same thing, to a less degree, would happen in a short, narrow section of tube, in a water-pipe line through which water is forced, or at the door of a crowded audience-room when a panic occurs. The short, thin wire has the same resistance as a larger one of much greater length. In the one case, the heat is generated in a small amount of material. In the large and long wire of the same resistance, the same heat will be liberated in a much greater amount of metal, and the rise in temperature will accordingly be less. The temperature rises until the heat generated in the wire each second equals the amount radiated. In the large wire the radiating surface per ohm of resistance is much greater than in the other. Measurements show that a current of one ampere flowing through an ohm of resistance will yield 0-24 heat-unit a second; that is to say, each ohm of the wire will heat 0'24 gramme of water through 1° C. in uring the heat developed in a wire carrying a current. The wire, K, is immersed in a badly conducting liquid contained in the vessel, C. Heavy refined coal-oil is generally used ; alcohol or distilled water, however, will answer the purpose. The current is measured by a galvanometer, and the difference in potential in volts on the two binding screws may be determined by means of an electrometer connected with them as before ex- The rise in temperature of the liquid is measured by a thermometer, T. A stirrer, S, is used to mix the liquid so as to secure a uniform temperature. The calorimeter, C, is supported by its flanged lip, which rests upon a felt washer, C'. When in use, the calorimeter may be placed in a tin can, which is mounted in a box containing loosely packed sawdust. This is intended to prevent loss of heat by radiation. Suppose the stirrer and can to be of brass, to heat a gramme of which one degree C. requires 0093 heat-unit. If they weigh 200 grammes, then for each degree of rise shown by the thermometer, 200 x 0-093 = 18'6 heat-units have been imparted to the can. If the can contains w grammes of water, and the temperature rise through T degrees during t seconds, the heat given to the water is w T heat-units. The whole heat generated is T 18'6 + w T heat-units. Evidently if the amount of water, w, the rise in temperature, T, the current, C, the resistance, R, and the time, t, be all observed, the amount of heat imparted to the calorimeter (here 18-6 T) can be computed from the equation. It will be the difference between the heat generated by the current and the heat given to the water, or — 0-24C9R* - wT. Heat-Waste in Wires. — In all wires carrying currents, a part of the electrical power is wasted. A mile of pure copper wire having a diameter of 0-23 inch will have a resistance of one ohm. The heat developed per second in such a wire when carrying a current of ten amperes, as is done in arc-light currents, will be 0-24 x 100 x 1 = 24 heat-units. 24x424-55 = 10,189 gramme- meters, or 10-180 kilogramme-meters per second. As one horse-power is 76 kilogramme-meters per second, the power lost in this mile of wire would be The Watt. — Electrical power is also expressed in terms of Watts, one Watt being the power of a current of one ampere in a circuit of one ohm resistance. The number of Watts in any case is the product of the number of volts and the number of amperes, or the product of the number of ohms and the square of the number of amperes. Since one Watt = 7^ horse-power, the horse-power is the number of Watts divided by 746. QUESTIONS.— Explain the development of heat in a current-carrying Avire. Suppose a current to flow through a wire which is thicker at one end than the other. If there is any difference in the strength of the current or in the temperature at the two ends of the Avire, state the difference and explain it. How many heat-units will a current of one ampere flowing through an ohm of resistance generate in a second ? If the current is doubled, how great is the heat ? Describe a calorimeter used for measuring heat in current-carrying \s-ires. Suppose the resistance of a Avire to be 07 ohm and a current of 10 amperes to be passed through it, IIOAV much heat \vill be liberated each second ? Explain heat-Avaste in AA'ires. Ho\v many heat-units are developed a second in a copper wire •?& of an inch in diameter, when carrying a current of ten amperes ? Convert this into Avork-units ; into horse-powers ; into Watts. Explain why it is that if you walk rapidly over a carpeted floor on a clear, cold day, you can produce a spark on presenting your knuckle to any metallic object, or to the face or hand of a person who has just entered the room. See whether you can light the gas by means of this spark. Required the difference of potential on its ends. Ans. 15 volts. An electrometer connected on the terminals of an electric light shows a potential difference of 40 volts. The current through the lamp is 10 amperes. What is the resistance of the lamp and arc between the terminals ? Ans. 4 ohms. How much heat will be developed in the lamp and arc each second ? Ans. 0-24x 10a x 4 = 96, or enough to heat 96 grammes of water, 1° C. The velocity of electricity depends upon the conditions. The actual velocity of propagation of electro- magnetic waves in space is the same as that of light, about 186,000 miles a second. The velocity of transmission of signals on telegraph lines is reduced very much by static capacity and self-induction. In one instance it was determined to be 16,000 miles a second between Washington and St. Louis ; and in submarine cables it is between 7,000 and 8,000 miles a second. The current passing through a telegraph wire is not injurious to birds because it does not leave the wire ; only an infinitesimal portion of it passes into the body of the bird. Should, however, a bird perched on a wire touch with any portion of its body a second wire during the passage of an electric current, the current might be deflected through the body of the bird with fatal consequences. Ingenious contrivances have been devised for killing mice and other small animals by making a connection through their bodies. It has been observed that all living muscles are traversed by electric currents, which are more marked in the case of the warm-blooded animals, and are known to persist for a time after death. Certain fishes are provided with electric organs having the property of accumulating electric force and communicating it in shocks to other animals. Such are the electric rays, the electric cat-fish of the Nile, and the gymno'tus or electric eel, the latter the most powerful of all. The gymnotus inhabits the marshy regions of Brazil and Guiana, where it attains a length of five to six feet. It is an object of terror to the inhabitants, for the discharge of its batteries, which are planted on the back of the tail and along the anal fin, is fatal to the largest animals. Certain roads are said to have been abandoned in consequence of the number of horses annually killed, while crossing swampy depressions, by eels. The electric fishes employ their singular power both as a means of self-defense and to disable or kill their prey. In order that a shock may be communicated to the victim, it is necessary that the galvanic circuit should be completed by connection with the fish at two distinct points ; painful sensations may be produced even by a discharge conveyed indirectly through the medium of water. The electric currents created at will in these animals have not been found to differ in their properties from those of the voltaic cell, in that they decompose chemical compounds, charge the Leyden-jar, render the needle magnetic, and even yield the spark. One surface of the electric organ is positive, the other negative. The power is exhausted after several discharges. servants of mankind. The Value of Electricity for Useful Work is entirely due to the fact that various effects can be produced by it with the greatest convenience, and such effects are usually more intense than those due to any other agency. The present useful effects of electricity are Magnetic, Inductive, Lighting, Heating, and Chemical. These are produced much better by electric currents, or dynamic electricity, than by frictional or static electricity, principally because the latter The Electro-Magnet. — We have already seen, in the case of the galvanometer, that a wire or coil, carrying a current near a needle, tends to make the needle deflect and take a position at right angles to the direction of the current ; we have also learned that this effect is proportional to the number of turns of wire passing around the needle. This very important discovery of the action of an electrical current upon a magnetic needle was made by Oerstedt (or'sted), of Copenhagen, in 1819. The experiment can easily be repeated by simply bringing near a compass-needle a wire connected with one or two cells of a battery. moved, or the current stopped. Such magnets are called electro-magnets, and usually consist of two wrought-iron cylindrical cores joined by a wrought-iron yoke, generally attached to the cores by screws, as shown in Fig. 385. Around called the coils, spools, helices, or bobbins. The coils should be wound or connected so that the current passes around one core in one direction, and around the other in the opposite direction, in order that one shall form a north pole and the other a south pole ; and the rule is, that the current should flow around the north pole in a direction opposite to that of the hands of a watch, if we imagine the watch and the end of the core both to face us. A bar of soft iron is used as an armature, and is very powerfully attracted when a strong current is passed through the coils ; but this magnetic effect continues only so long as the current flows, and the instant the circuit is broken the attraction ceases almost entirely. The slight effect whiob remains is called residual magnetism, and is similar to the retentivity or coercive force of permanent magnets. Since this residual magnetism is hardly perceptible in very soft wrought-iron, but is very strong in hard steel, and since a certain-sized electro-magnet of soft iron can be made to exert a much stronger attraction than one of steel, the softest and best quality of soft iron should, therefore, be used in the construction of electro-magnets." A magnetic effect may be obtained from a coil of wire carrying a current, even though the coil has no iron core within it. Such a coil without a core is called a solenoid, and is sometimes used instead of an electro-magnet. The magnetic effect is, however, very much weaker if there be no iron core, the presence of iron tending greatly to concentrate and conduct the magnetic lines of force. that was developed is The Electro-Magnetic TelegTaph. — The simplest system of telegraphy, and the one most extensively used, is that invented in 1837 by S. F. B. Morse, an American. The Morse apparatus consists essentially of an electro-magnet, which, when a current passes through its coils, attracts an armature. In this way an operator can cause the armature to move, even at a distant station, by simply sending a current over a wire leading to that station. ward end of the lever is depressed. By means of this key, the operator sending the message can cause a with that of the sending key. The receiving instruments are of two kinds, the most common being the " sounder " (Fig. 387), which consists of an electro-magnet fixed vertically upon a flat base. The armature, which is a strip of soft iron, is mounted horizontally immediately above, but not touching, the poles of the magnet, and at the middle of a lever pivoted at one end. Screws are provided at the other end of the lever to regulate its up and down movements, and there is also an adjustable spring which always tends to draw the armature up. TELEGRAPH REGISTER. 509 When a current is passed through the magnet, the armature is drawn down, causing a click ; and, when the current is stopped, the armature is pulled back by the spring, causing another click. If the current sent over the wire lasts only for an instant, a dot is impressed on the tape ; but, if the current is continued, a dash appears. The marks are made on the tape either by simply indenting the paper with a sharp point or stylus on the end of the pivoted lever carrying the armature, or by means of some form of pen fed with ink. The Alphabet, or Code of Signals, by which messages are sent, is composed of different combinations of dots and dashes — that is, short or long impulses of current over the line. The code used in this country, presented on the next page for reference, is the one originally devised bj Professor Morse. The different signals are carefully selected, so that those used most frequently are the shortest, A slightly different code is employed in Europe. This was intended to be an improvement on the original Morse alphabet, but the European code has been found to require more time to send a given message. Italics It should be carefully noted that 0 differs from I in that the two dots are farther apart ; L is twice, and the cipher three times, as long as T. C and R differ from S and from each other by being differently spaced. The same is true of H, Y, Z. etc. Skilled operators experience no difficulty in making these distinctions. not have sufficient strength to work the receiving instruments directly ; in such a case, a relay or repeater is used. The regular form of relay is shown in Fig. 389. It consists of an electro-magnet and pivoted lever carrying the armature, similar to the sounder ; but in the relay a great many turns of very fine wire are used, in order to multiply the effect of A TELEGRAPH CIRCUIT. a weak current. The armature and lever are also made very light, so as to work easily ; and a platinum contact-point, similar to that on the key, is mounted on the end of the lever, so that, when the armature is drawn forward, a local circuit, in which are included a local battery and the receiving sounder or register, is closed. The object of the relay is, therefore, to re-enforce with a strong local current any current too weak to do the required work itself. The connections for the regular Morse circuit for one intermediate and two terminal stations are shown in the diagram (Fig. 390). If we trace out the connections in this diagram, we find that when the key K at the station A is depressed, it will send a current over the line from the main battery, M B, causing the armatures of all three of the relays, R, R2, R3, to be drawn forward. This will close the local circuit at each station, and the local batteries, Ib, lb, lb3, will cause the armatures of the three sounders, S, S2, S3, to move simultaneously in perfect correspondence with the motions of the sending key K. It will be noticed that the wire is carried to the plate G in the earth at each end of the line. By this means the earth is made to act as the return conductor to complete the circuit, and it is thus necessary to have only one wire, which effects a great saving on long lines. The keys are all kept closed except when used in telegraphing. Faults may occur in Telegraph Lines from a number of causes : First, the wires may break, which, of course, entirely interrupts the signaling; secondly, the insulators may break or become imperfect, so that the current on the wire leaks off to the earth before it reaches the distant station, and thus weakens the effect ; or, thirdly, two wires may Various methods for testing the existence and positions of faults are used by telegraph engineers. They usually depend upon accurate measurements of resistance or capacity (see page 485). sages through one wire at the same time. One of these methods of duplex working is called the Wheatstone Bridge method. Fig. 391 illustrates the principle. All that is necessary in a duplex system is that the receiving instrument at each end should move only in response to signals from the other end, so that an operator at A may cause the receiving instrument, S, to work without affecting his own receiving instrument, T. The same must be true from the other end also. In order to accomplish this, the circuit at each end is divided into two branches, one of which connects with the earth and the other with the line, and the receiving instrument is placed across between these branches. Now, by the principle of the Wheatstone Bridge, if the resistance in F is to the resistance in Z as the resistance of the line is to the resistance of H, then no current will flow through the instrument when the key at A is closed ; but if a current be sent from the other end, B, a portion of this current will flow through the receiving instrument, T, and cause it to work. In this way, signals can be sent at the ends from which they are sent. Multiplex Telegraphy. — By a further extension of the principle of duplex telegraphy, it is possible to send four messages on a wire at the same time, and some ingenious methods have been invented by means of which it is possible to send seventy-two distinct messages on the same wire at the same time ; but, of course, such systems are extremely complicated, and practically useless. are quite cheap, and enable the pupil to learn how to send and receive telegraphic messages. They may even be used on short lines, up to about one mile in length. The methods of telegraphing between places separated by water are very similar to those employed on land lines ; but in the case of submarine telegraphy several serious difficulties are encountered, which make it necessary to use more nearly perfect lines and instruments. In the first place, if a telegraph wire is laid under water, it must be perfectly insulated throughout 514 PRACTICAL APPLICATIONS OF ELECTRICITY. its length with some non-conducting and water-proof covering; otherwise the current used in telegraphing would all leak off the wire in a very short distance. Submarine cables, therefore, consist of a core or conductor proper, made of several (usually seven) copper wires twisted together in order to be flexible. This core is covered, first with a stout layer of gutta-percha, then with a woven coating of jute, and finally with a sheathing or armor of ten iron wires, each covered with hemp. These are wound on the outside, and give the finished cable the appearance of a rope about one inch in diameter. The strength of the cable depends upon this armor ; and the breaks in cables, which so often occur and cause so much trouble and expense, are almost always due to the failure of this armor to stand the severe pull and scraping to which the cable is subjected. Another serious difficulty in submarine telegraphy is the fact that a cable acts as an enormous Leyden-jar. which requires a large quantity of electricity to charge it. When a current is sent over the cable, the current has to fill the cable, as it were, before it can work the receiving instrument at the other end. This effect, which is called Static Induction, greatly reduces the speed of signaling through cables, so that not half as many words can be sent per minute as on ordinary land lines. The existence of static induction also makes it necessary to use extremely sensitive instruments to receive the signals ; in fact, it was for this purpose that Sir William Thomson devised his mirror galvanometer, which, we have seen, is also used in laboratories for measuring very weak currents. The motion of a spot of light reflected from the mirror enables the receiving operator to read the signals sent. Electric Bells. — In many cases where it is not desired to send messages over a wire, but merely to make a sound to attract attention, electric bells are used. They consist of an electro-magnet and a pivoted lever carrying an armature similar to the sounder ; but the lever is arranged to strike the bell when the armature is drawn forward, instead of merely striking the screw-point. In order to operate an electric bell, all that is necessary is to send a current through the coils of its electro-magnet. The usual means employed The bell above described is what is known as a single-stroke bell, since it sounds but once each time the push-button is pressed. The continuous-ringing electric bell, which is the one generally used, because it has the advantage of keeping up the ringing as long as the button remains pressed down, is shown in Fig. 393. It differs from the bell already described in that the circuit passes through the lever which strikes the bell. When the armature is drawn forward, it breaks the circuit at the contact-point shown on the back of the armature. This allows the armature to drop back, after having struck the bell. The action is then repeated, causing a vibration and continuous ringing as long as the push-button is pressed. Such electric bells are used for many purposes, as door-bells, call-bells, and burglar-alarm bells. In the burglar-alarm, the push-button is replaced by a contact-point on the door or window, so arranged that when the door or window is opened, the circuit is closed and the bell rings. An attachment is often added by means of which the bell, once started by opening the window, will continue to ring after the window has been shut down again ; otherwise, the ringing might not last long enough to give sufficient alarm. Electric Clocks. — Another very similar application of electricity is the electric clock, the simplest form of which consists merely of one or two hands that are caused to move around by means of an electric magnet. The hands advance by what is called a " step-by-step motion " each time an electrical impulse is sent over the wire from the standard clock. The circuit is closed once every second. One master-clock, as it is called, may operate a number of electric clocks placed around at diff-erent points on the same circuit It is in this way that standard time is sent over the country from the observatory at Washington or other important astronomical observatories. QUESTIONS.— Explain the value of electricity for performing work. Enumerate the useful effects. Explain the principle of the Electro-magnet. What is a solenoid ? Why are electro-magnets preferable to permanent magnets ? Describe the Morse system of Telegraphy ; the key, and its object ; the sounder ; the Morse telegraph register. Explain the relay, and state its object. Draw a diagram illustrating a Morse telegraph circuit. How can two messages be transmitted through one wire at the same time ? Explain the Wheatstone Bridge method. How may the principle of duplex telegraphy be extended ? What difficulties are encountered in submarine telegraphy ? Of what do submarine cables consist ? Why are extremely sensitive instruments required to receive the signals ? When was the first telegraph line built ? In 1844, between Baltimore and Washington. How many miles of telegraph line are there now in the world ? Nearly 800,000. The electric wire in operation in New York City alone is long enough to encircle the earth three times at the equator. INDUCTIVE EFFECTS OF ELECTRICITY. Electro-Magnetic Induction. — We have already seen that a charge of electricity has the power to induce another charge in a body near it. This is called Electrostatic Induction. In the case of dynamic or current electricity, we also find that, when a magnet is moved near a wire, a current of electricity will be produced in the wire ; or if an electro-magnet is suddenly excited by sending a current through its coils, a current will be produced in a wire or coil near the electro-magnet. In fact, any change whatever in the position or the strength of a magnet will tend to produce a current in a neighboring wire or coil. The explanation of this phenomenon is usually expressed, according to the views of Faraday, by saying that the magnetic lines of force cut the wires or the wires cut the lines of force, which is the same thing. These lines of force are imaginary ones, which for convenience we assume to represent the magnetic force of attraction in the neighborhood of a magnet. An idea of these lines has already been given in the case of the magnetic figures made of iron-filings (page 429). We have also seen that an electric current always has magnetic effects, and will turn a compass-needle. Therefore, when we move a coil carrying a current or vary the strength of the current in the wire, we shall produce a current by induction in the neighboring wire or coil. Thus we see that any magnetic change tends to produce an electric current in a wire in the neighborhood ; but it must be borne in mind that a change of some kind is necessary. The mere presence of a magnet near a wire produces no effect whatever unless the magnet is moved or changed in strength. and surrounded by a coil of 30 or 40 turns of insulated wire. If a magnet is now thrust into the first coil or brought near it, the needle of the galvanometer will swing, showing that a current is generated in the coil. In fact, with a delicate galvanometer it will be very difficult to move either the coil or the magnet, even when they are a yard apart, without affecting the galvanometer-needle. If the magnet is replaced by a coil of wire connected with one or two cells of a battery, a similar set of experiments will show the induction currents made by the motion or variation of another current. This electro-magnetic inductive action is of the utmost scientific and practical importance, since many of the useful applications of electricity are based directly upon it. For example, the dynamo-electric machine, the electric motor, and the telephone, are all apparatus for producing and using inductive action. The simple experiments suggested above will greatly aid the pupil in clearly understanding the principles of these machines, which are the three most important pieces of electrical apparatus. The Induction Coil consists of an iron core surrounded by a coil usually made of three or four layers of coarse wire, the ends of which are brought out to binding-posts. Outside of this coil there is a second coil, usually consisting of a great at each end to hold the wire in place. The action of this coil is nothing more than the simple inductive action already described. When the current from a few cells of a battery is caused to pass through the coil of coarse wire called the primary coil, a current is produced in the secondary coil of fine wire, because the passage of the primary current makes the iron core strongly magnetic. Since this inductive action is exerted on each turn of wire in the secondary coil, it is evident that the total effect obtained from a large number of connected turns must be very marked, and this we find to be the fact. It is possible to obtain, from a comparatively small coil, sparks one quarter of an inch long when two or three cells are used on the primary circuit, whereas the cells alone would not be able to make a spark one thousandth of an inch in length. With a large induction coil we can increase the tension or jumping power to such an extent that we may cause the induced current to run round a theatre and light hundreds of gas-burners. Very large induction coils have been made with as many as 3,000 or 4,000 turns of wire in the secondary ; some of them give a spark four or five feet long. A spark is produced by an induction coil each time the primary circuit is closed or opened. The multiplication of effect is, however, only in the tension (designated as E. M. F., electro-motive force) of the current, and the -actual energy in the secondary circuit can not be greater than that in the primary circuit. It will probably be considerably less, because of various losses. All we accomplish is to get a very much higher E. M. F. (measured in volts) than we have in the primary circuit, while the actual current of the secondary (measured in amperes) is much less than that of the primary. In short, we simply transform the electricity, and for many purposes this change of E. M. F. is desirable. It is usual in induction coils, also called Ruhm'korff coils, to have some mechanical arrangement run by clock-work for opening and closing the primary circuit ; or we may use an " electric buzzer," working on the same principle as the continuous-ringing electric bell, and applied to the end of the iron core of the induction coil. The Telephone. — The transmission of speech by electricity is effected by means of an instrument called the Telephone, which depends entirely upon induction for its action. The ordinary Bell telephone, an extremely simple instrument, shown in section and in perspective in Fig. 396, consists of a magnet, M, having at one end a coil of very fine wire, S, and a sheet-iron diaphragm, Gr G, close to, but not in contact with, the magnet. These three parts — the magnet, coil, and diaphragm — are really all that is essential to the telephone. They are contained in a wooden case, F, having a mouth-piece, E. The connections from the two ends of the coil S are carried by two wires, C C, to two binding-posts, D D, at the other end of the instrument. In order to use the telephone, we need simply connect two instruments in a complete electric circuit. Then, when we speak into the mouth-piece, the diaphragm will be made to vibrate by the sound, and its motion near the magnet, M, will cause variation in the lines of magnetic force, which we know will produce electric currents in the coil S. These currents will flow over the wires to the other telephone at the opposite end of the line, where they will in turn change the strength of the magnet, causing the diaphragm of the second telephone to move in perfect unison with that of the first. Thus we see that the sound-waves of the voice are turned into electrical waves in the first telephone, from which they travel over the wires to the second telephone, to be converted back into sound-waves. The action is so nearly perfect that it is possible to recognize a familiar voice. The Bell telephone may be employed in this way either as a " receiver " or " transmitter," but ordinarily it is used only for receiving. The Usual Form of Transmitting- Telephone is that invented by Edison and Blake. It consists simply of a carbon button in contact with a diaphragm, and a contactpoint through which the electric circuit is carried. When the diaphragm vibrates, it varies the pressure on the contact-point, changing the resistance to the passage of the current, and producing waves of current in the circuit corresponding to the vibrations of the diaphragm. The connections for this kind of telephone are shown in Fig. 397, in which C is the carbon button mounted on a spring ; D is the diaphragm ; and F is the contact-point, placed between the two and in contact with both. The button is connected with the line wire which runs through the receiving instrument, R, and then to the earth, returning through the earth to the starting-point, where it passes through the battery, B, gram of Fig. 397. The current obtained from the secondary coils, S S, is carried by the line wire to the receiving instrument at the other end. In this way, the E. M. F. of the current is raised so that the current is more easily carried over the wire, and the effect of the variable resistance of the contact-point is relatively greater than if no induction coil were added. of speech. The Microphone is precisely the same in action as the transmitting telephone, it being really nothing more than a loose contact-point consisting of two pieces of carbon lightly touching each other, and included in a circuit with one or two cells of a battery and a Bell telephone. The slightest vibration will jar the contact and vary its resistance, producing a sound. For instance, the ticking of a watch is distinctly heard, and even the footfalls of an insect under favorable conditions will produce vibration enough to make a sound in the telephone. The Dynamo-Electric Machine is the most important of all electrical apparatus, as it is the generator or source from which ninety-nine per cent of all the electricity now ing electro-magnetic induction, it was shown that, when a wire is moved in the neighborhood of a magnet, an electric current is generated in the wire. This is the essential principle of the dynamo-machine — in fact, a wire caused to move near a magnet is an elementary form of dynamo. The power of the current obtained by this inductive action depends : 1. Upon the strength of the magnet ; 2. Upon the length or number of turns of wire ; 3. Upon the speed of the motion ; 4. Upon the conductivity of the wire. The particular means used to secure these conditions are different in each machine, and hundreds of different forms have been invented. The common dynamo, however, is simply a coil or series of coils of wire, known as the armature, revolving between the poles of a powerful electro-magnet, called the " field magnet," which produces the magnetic field in which the armature revolves. The Gramme King-. — There are two principal types of armature used in dynamos. The first is called (from the name of its French inventor) the Gramme Eing, and consists of a ring of iron wound around with wire, which virtually forms one endless coil. Connections are made with this coil at various points, each of which is in communication with a number of insulated copper bars, made into a cylinder called the " commutator." Now suppose this ring armature to revolve between the poles of a magnet ; then one side of the ring will be acted upon by the north pole and the other side by the south pole, and currents will be produced in the wire in one direction on one side of the ring, and in the opposite direction on the other. These currents will meet in the middle, either at the top or bottom of the ring, if the poles of the field magnet are on each side. If two conducting brushes are placed in contact with the upper and lower points of the commutator, respectively, the currents produced in the two sides of the ring will unite and flow out of one brush through any circuit which may be provided, and back to the armature through the other brush. This action is kept up so long as the armature revolves, and a continuous current of electricity is obtained. The object of the commutator and brushes is to make sliding contact with the armature, which revolves at a high speed, and also to obtain a continuous current by causing the coils under the influence of the north pole, and those under the influence of the south pole of the field magnet, always to be connected with the circuit in the same way, and therefore to produce a continuous current. The Siemens Armature. — Another important form of armature is the Siemens Drum Armature, which consists of a drum or cylinder of iron wound longitudinally with a number of sections of insulated copper wire, forming one endless coil. Each section is wound in a different direction or plane, and is connected with one bar of the commutator. The workmen are applying the insulated copper wire lengthwise around the armature-core. The ends of the section in which the wire is wound are seen projecting at the left. These ends are subsequently attached to the sections of the commutator ; and insulated binding-wire, of poorly conducting German silver, is wound round the cylinder in successive bands to hold the coils in place. rent in one direction and the other half in the opposite direction, the two currents being united to the circuit and taken off by the brushes. The Edison dynamo-machine has an armature of the Siemens or drum type, and its field magnet is a massive horseshoe. In the first electrical generators, the field magnets were permanent magnets, and the machines were called magneto-electric generators ; but in 1867, Siemens and Wheatstone independently conceived the idea of using the current generated by the machine itself to excite the electro-magnets which formed the field magnet. This great invention was thought at the time to be most remarkable, since it appeared to imply a principle similar to that of a man attempting to lift himself by his own boot-straps. But, as a matter of fact, there is no reason why a machine should not feed its own field magnet, since the current required for this purpose is rarely more than five per cent, and is sometimes as low as one per cent, of the total current produced by the machine. The only difficulty is that there must be some magnetism to start with, or the machine will not " excite " or " build up." There is usually, however, sufficient residual magnetism to generate a little current; this strengthens the magnetism, which in turn produces more current, and so on, till the full strength is reached. The Alternating-Current Dynamo. — The machines so far considered produce direct currents — that is, currents which always flow in the same direction, and which result from the use of the commutator, as described. If, however, the ends of the coil of wire forming the armature are connected with two copper rings on the shaft, and brushes are kept in contact with these rings when the armature revolves, then an alternating current will be produced, because the coil will first pass the north pole and then the south pole, producing a current first in one direction, then in the other. This kind of current is called an alternating current, and its importance and extensive use are due to the fact that, by means of a transformer, which is merely an induction coil, the E. M. F. of this current may be raised or lowered as desired. Hence, it is possible to send a current of high E. M. F. over a comparatively small wire, and, where it enters a building, to reduce the E. M. F. to a safe point, by a transformer, thus saving the cost of a large wire. It is impossible to trans- form a continuous current in this way, as we have seen that a steady current has no inductive effect. An alternating-current dynamo, capable of running a thousand incandescent lamps, is shown on page 505. many different purposes. They are employed to generate electric currents for electric lighting, electro-plating, motive power, telegraphy, charging storage-batteries, electric welding, etc. The medical electrical machines, which turn by a handle, are virtually small dynamos. The advantages of the dynamo are twofold : First, a comparatively small machine will produce a powerful current (for instance, a machine weighing twelve hundred pounds — the weight of a large horse — will easily generate fifteen horse-power of electrical energy) ; secondly, the efficiency of the dynamo is remarkably high, there being machines in ELECTRIC MOTORS. 527 practical use capable of generating electric power to the extent of over ninety per cent of the mechanical power applied to them. The mistake should not be made, however, of supposing that the dynamo runs itself, or that very little power will run it. Mechanical power of some kind must be applied to the shaft in order to turn the armature, and the result obtained in electric current is directly proportional, and nearly equal, to the mechanical power applied. Only two kinds of machines are commonly used for running dynamos — the steam-engine and the water-wheel. Electric Motors. — We have seen that, when the armature of the dynamo is revolved, a current is generated ; this action can be reversed, and a current sent through the armature which will cause it to revolve. The principle here is the same as that involved in the production of a current in a wire moved near a magnet, and conversely, in the motion of a current-carrying wire near a magnet. The same machine can be used either as a dynamo or a motor, a good dynamo being a good motor ; but ordinarily, for practical reasons, motors are made slightly different from dynamos. Electric motors are used for many purposes, the most important of the applications being to ventilating- fans, pumps, printing-presses, lathes, drilling-machines, circular and band saws, sewing-machines, grindstones, etc. The great advantages of electric motors are that they occupy little space, they require little or no skill to run them, arid they are economical, for the reason that they need be operated only when required, as the current can be turned on or off instantly. Transmission of Electrical Energy. — The dynamo is a machine for transforming the mechanical energy of a steam-engine or water-wheel into electric energy, while the electric motor transforms the energy of the electric current into mechanical energy. It is obvious, therefore, that we may run a dynamo with a steam-engine or water-wheel at a certain place, and carry the current produced by the dynamo over a conducting wire to an electric motor at some other place where work is to be performed. The transmission of energy in this way has three great advantages : First, the electricity can be carried a great distance (even as far as thirty or forty miles) ; second, it is possible to run a great many small motors for different purposes from one circuit, so that the power generated at one central station by large steam-engines or waterwheels can be distributed to hundreds of different motors scattered through a manufacturing town ; and third, the electrical energy can be transmitted over a very small conductor, a wire one fourth of an inch in diameter being capable of transmitting twenty-five horse-power at 220 volts, which is a perfectly safe E. M. F. Electrical Railways. — The most important illustration of the transmission of electrical energy is the electric railway. The commonest and most successful electric railway system consists of a central generating station having a number of large dynamos, usually run by steam-engines. From this station, the current generated is carried by copper wires along the line of the railway, usually immediately over the middle of the track and about fifteen feet high. The current is taken off this conducting wire by an arm attached to the top of the car and having a trolley at the end, which runs along and makes continuous contact with the wire. This current is carried to an electric motor placed underneath the car and connected with the axle. When the man running the car wishes to move forward, he simply closes the circuit with a switch and allows the current to flow through the motor, thus causing the motor and car-wheels to revolve. In order to cause the car to move backward, the current through the motor is reversed. Instead of running street-cars by this overhead-wire system, storage-batteries placed directly upon the car itself are sometimes employed to furnish the current for the motor. This plan has an advantage in that the car carries its own supply of electricity, and therefore requires no wire leading along the track. The disadvantage of the system is the great weight of the batteries, which amounts to several thousand pounds. The storage-battery used for this purpose will be described later (see page 535). HEATING AND LIGHTING EFFECTS. 529 QUESTIONS.— Illustrate Electro-magnetic Induction. How is the phenomenon explained ? Can you suggest an experiment which will throw further light upon the principle ? Show how electro-magnetic inductive action is applied. Explain the construction of the Induction Coil. State fully the principle involved. Give an idea of the power and uses of the induced current. What is gained by this transformation of electricity ? What purpose does the Telephone serve ? Explain the principle of the ordinary Bell Telephone ; illustrate by diagram. Of what does the usual form of transmitting telephone consist ? Draw a diagram illustrating the details of a telephone circuit. Describe the Microphone. State the importance of the Dynamo-Electric Machine, and the principle of its construction. Upon what does the power of the current obtained by means of this machine depend ? What is essentially the common dynamo ? Describe the Gramme ring ; the Siemens armature. How is the current generated by the machine itself utilized to excite the electro-magnets ? Describe the Alternating-Current Dynamo, and state its advantages. What are the uses of dynamos ? What kind of machines are employed for running them ? Explain the principle of Electric Motors. For what are they used, and what are their advantages ? How is electrical energy transmitted ? Describe two methods of running street-cars by electricity. Production and Control of Heating Effect If a strong current of electricity is passed through a small wire, the wire will become heated ; if the strength of the current be increased, its temperature will rise until it becomes redhot, then white-hot, and finally the wire may even melt or vaporize. It is difficult to get great heating effects from a small number of cells ; but two or three cells of a bichromate of potash battery, particularly if connected in parallel, will give a sufficient current to heat a fine copper wire or an iron wire red-hot. The thinner the wire and the shorter its length, the easier it is heated. The principles and quantitative facts in regard to the heating effects of currents have been fully described on page 500. The currents from dynamo-machines are strong enough to melt wire, although it is dangerous to use them for this purpose, as it puts a sudden strain upon the machine and is also liable to melt the wires with which the armature is wound. Large dynamo-machines have been made capable of giving a current strong enough to melt a solid bar of copper as thick as a man's wrist. The most important application of this heating effect is the electric lamp, which is merely a device for producing it with sufficient intensity and steadiness to give a practical light. There are two kinds of electric lamps, the arc and the incandescent or glow lamp. Arc Lamps. — If the terminals of two wires leading from a powerful battery or dynamo be brought together, and then separated about an eighth or sixteenth of an inch, the current will continue to flow across the space between the ends of the wires, producing a light of dazzling brilliancy. This light is due to the intense heating effect of the current caused by the resistance at the point where it flows across. The ends of the wires are raised to a white-heat of sufficient intensity to melt any known sub- are used for this purpose. Two carbon rods with the current passing between them are shown in Fig. 401. It will be noticed that the path of the current is in the form of an arc, from which fact the arc lamp and voltaic arc take their names. Even carbon is slowly vaporized and burned away in the electric arc ; therefore, to make the light steady, it is necessary to have some way of feeding the carbons as they burn. This is accomplished by clockwork mechanism, which feeds the carbons together as fast as they are consumed ; or by means of a mechanical clutch arrangement, which allows the upper carbon to drop a little by its own weight when the distance between the carbons becomes too great. A regular form of arc lamp is shown in Fig. 402. ELECTRIC LIGHTING. wire was first used for this purpose, but it was found liable to melt ; thin strips or filaments of carbon were therefore substituted in incandescent lamps. The filament of the Edison lamp is carbonized bamboo; but carbonized thread and even hair have been employed for this purpose. The use of carbon makes it absolutely necessary to remove all the air from around the filament, otherwise it would be burned up as soon as it became red-hot. Hence, the filaments are inclosed in a glass bulb, from which the air is pumped with a mercury air-pump ; the bulb is then hermetically sealed. The air-pump used is so effective that only one-millionth part of the air is left in the bulb. The construction of the Edison lamp is shown in Fig. 403, in which G is the glass bulb, L is the loop or filament of carbon, E E are platinum wires connected with the ends of the filaments and leading through the glass, one of which is connected with the brass ring, B, and the other with the brass button, D, at the bottom of the lamp. When the lamp is screwed into the socket that holds it, this ring and button are in contact with brass pieces in the socket, which in turn are connected with the wires supplying the current. An electric lighting plant consists of one or more dynamos for generating the current, switches for controlling the current, wires for carrying the current to the places where it is to be used, and lamps for converting the current into light. The two kinds of lamps are connected with the circuit in entirely different ways. Arc lamps are connected in series — that is, the current flows through one, then the next, and so on — whereas the incandescent lamps are connected in parallel — that is, the current divides or branches into a number of parts, each of which flows through a single lamp. The chief advantage of arc lamps is their great power and comparative economy of current. Thus it costs only two or three cents an hour to produce a light of six or eight hundred candle-power ; and only a single small wire is required, which may be run for six or eight miles, with the lamps attached wherever desired. Arc lighting is suited to large spaces, such as streets and parks. The advantages of incandescent lighting are that the light is more distributed and not so intense at one point, and that it is very much more steady than the arc light— in fact, it is among the steadiest artificial lights known. The electric light has been used in capturing deep-sea fishes two miles below the surface ; it is proposed to employ it in photographic apparatus for the purpose of making negatives of the ocean-bottom. Danger in Electric Lighting. — Arc lamps, being almost always run in series, require a high E. M. F., usually from 1,000 to 3,000 volts. Incandescent lamps, on the other hand, being almost always run in parallel, require only from 50 to 120 volts. The principle of this difference has been illustrated by pumps on page 478. It therefore follows that touching an arc circuit is usually much more dangerous than contact with an incandescent circuit, the effect on any animal being directly proportional to the E. M. F., other things being equal. The danger limit is between 300 and 500 volts ; below this the effect may be disagreeable, but is not serious. All danger is obviated by perfect insulation and avoidance of actual contact. Electric Welding. — There are other applications of the heating effect of electricity besides electric lighting. The most important and most recently developed of these is electric welding. The art consists simply in placing together the two pieces of metal to be welded, and passing a very powerful electric current through the juncture. This heats the surfaces of the metal in contact to such an extent that they fuse together and make a perfectly solid joint. The convenience and effectiveness of electric welding are ELECTRIC WELDING AND PLATING. 533 remarkable. Only the surfaces of the two metals are heated ; therefore the amount of heat required is very small, and the metals are not made black and dirty as they would be if placed in a fire. It is also possible in this way to weld brass and copper to iron and steel. Heretofore, welding had been confined to iron and steel ; new it is possible to weld electrically almost any two metals. The ordinary form of electric welding apparatus consists of two sliding clamps for holding the metals to be welded. These are connected with a dynamo-machine specially made to give a current of several thousand amperes. When the metals are brought in contact, the current flows across the joint and fuses them together. The current is then stopped and the joint solidifies. Electric Furnaces. — Electricity has been used in a somewhat similar manner for reducing metallic ores, melting metals, etc. The electric furnace or crucible for this purpose is provided with two electrodes or conductors, usually heavy plates of carbon, between which the material to be treated is placed. When a powerful current is passed between the electrodes, the material is intensely heated. Electricity lias even been used for Cooking Purposes, the heat being produced by passing a strong current through conductors which offer resistance to its passage. For example, if a coil of wire be placed in a vessel of water, and a strong current be passed through it, the water will become sufficiently heated to boil an egg. Electro-Plating-. — When an electric current is passed through any liquid which is a conductor, a chemical effect is usually produced in the liquid. In the case of a solution of some metal, the latter will be deposited on the cathode, as already described (page 488). length of time it passes. Secondary, or Storage-Batteries. — The principle of Storage-Batteries is very similar to that of electro-plating. The batteries are made up of plates of lead (the electrodes), or an alloy of lead, cast in the form of a " grid/' or frame- work of bars crossing one another at right angles, as snown in Fig. 405. The holes in the plate are filled with a paste of lead oxide. For the positive plates, the paste is made of red lead and sulphuric acid ; while for the negative plates, litharge and sulphuric acid are used. The positive and negative plates are placed alternately in a bundle (Fig. 406). They are kept apart by strips end of the cell by means of their connecting strips. The positive plates are connected at the other end. The manner of connecting the cells is shown in Fig. 407. The liquid surrounding the plates is dilute sulphuric acid. When the battery has been exhausted, it is charged by connecting a dynamo with the terminals of the battery, and sending a current through it. This current reverses the chemical action, which goes on during the discharge of the battery. As already stated, the platingvat behaves in a similar manner. Storage-batteries have an electro-motive force of 22 volts per cell. The resistance per cell depends on the size and number of plates composing each cell ; it is usually 0-005 ohm, or less. ELECTRICITY IN WARFARE. Electricity 011 Ships-of-War. — One of the most important and extensive applications of electricity is to military and naval operations. The electric search-light, which is merely a very powerful arc lamp with a reflector, may be effectively used on a ship-of-war at night to enable her to enter harbors, avoid obstructions, detect the presence of lostile vessels, torpedo-boats, floating torpedoes, etc. A i imber of electric motors are often employed on a mari-of war to drive ventilating-fans, manipulate the heavy guns, ' oist and set in place the enormous cartridges, revolve the turrets, etc. Electric signals also place in communication different parts of the vessel. Electricity has been employed in land warfare for field telegraphing, exploding mines and torpedoes, illuminating magazines, where the use of any other artificial light would be perilous, etc. The velocity of cannon-balls is now accurately measured through the agency of electricity. The Uses of Electricity in Medical Practice are many and varied. Applied to the muscles or nerves, it may tell us of the presence of disorder ; and, where derangement is found to exist, it may restore the functions of the organs involved, as in cases of curable paralysis and wasting of the muscles. The sudden change of state produced in the muscle or nerve by the interrupted current, throws it into healthy action. In disorders of the brain and spinal cord, the use of electricity is often followed by favorable results ; while in certain forms of neuralgic troubles, like lumbago and sciatica, it sometimes affords speedy and permanent relief. In conditions attended with failure in respiration, as in poisoning by opium or impending heart-failure, life may be saved by exciting the muscles of breathing with a Faradic current. There are also conditions in which electricity has a general tonic effect on the whole system. Physicians employ the electric light for illuminating the cavities of the ear, nose, mouth, throat, and stomach. Objects that could not otherwise be seen and investigated are thus brought into view. A platinum wire heated to a white-heat by the galvanic current forms an instrument known as the galvano-cautery, of great service .in the hands of the surgeon for the removal of tumors and diseased tissues. Electric engines are used both by surgeons and dentists to furnish the steady power necessary for the manipulation of instruments in delicate operations. In order that benefit may be derived from electrical treatment, it must be applied by an experienced and careful practitioner. In the hands of the charlatan, electricity is an uncertain and even dangerous agent, QUESTIONS.— What can you say of the production and control of Electrical Heating Effect ? Explain the principle of the Arc Lamp. Why are carbons used, and how is the feeding of the carbons regulated ? Describe the Incandescent Lamp, and illustrate the principle by diagram. Of what does an electric lighting plant consist ? State the advantages of arc lamps ; of incandescent lighting. Discuss the question of danger in connection with each. Describe Electric Welding, and show what has been accomplished in this line. How has electricity been utilized for smelting and cooking purposes ? Describe the process of Electro-plating. Explain the Storage-battery and its applications. What are the objections to Storage-batteries. State the uses of electricity in warfare ; in medicine and surgery. Assume that you have a lathe in your workshop, and half a mile away there is a small waterfall ; describe a means of driving your lathe by this water-power. (Suggestions : Water-wheel, small dynamo, wire to workshop, electric motor belted to lathe.) The earth can be used as the return conductor by burying a plate at each end of the line. If a ten-horse-power water-wheel is used to drive a dynamo, the current from which runs an electric motor half a mile away, what is about the maximum power that can be obtained from the motor ? About seven horse-power ; because one horse-power would be lost in the dynamo, one on the line wire, and one in the motor, these losses being due to friction, heating of the wire, etc. Foucault revolved a copper disk between the poles of a strong magnet, and found a decided resistance to the revolution of the disk, although it did not touch the poles ; the disk also became hot. Why ? And why would such a disk become hotter than the armature of a dynamo which also revolves between the poles of a strong magnet ? TJie disk had currents generated in it exactly as in the armature of a dynamo, only in FoucauWs disk the currents flowed round and round, thereby heating the disk ; ivhereas in the armature of a dynamo the wires are separated by being insulated, which prevents these local currents between the different parts of the coil. But if two parts of a coil cut through the insulation and come in metallic contact, causing a "short circuit," then that portion of the coil becomes very hot, like Foucault's disk. If you wind an ordinary horseshoe permanent magnet with a number of turns of wire, the ends of which are connected with a galvanometer, and then alternately put on and pull off the keeper of the magnet, what effect will be produced in the galvanometer ? The needle will swing one way when the keeper is put on, and the other way when it is taken off, because of the generation of currents by the increase in the number of lines of magnetic force passing through the coil in the first case, and the decrease of lines of force in the second case. This action is precisely like that of the Bell telephone when used as a transmitter. What effect is produced on the light given by an incandescent lamp when the electro-motive force supplied to it is raised ? If there is a great increase in light, why not always run incandescent lamps at a high electro-motive force ? TJie light increases very rapidly by increase of E. M. F., being doubled with only about ten per cent increase in electrical energy. Unfortunately, the life of the lamp— i. e., the average number of hours it will burn without renewalis greatly reduced when it is run at a high temperature, because of the deterioration of the filament ; therefore a compromise is adopted, the proper point being that at which the lamp gives a yellowish and not a Wm's/i-white light. The pound avoirdupois contains 7,000 grains. The same figures which represent the specific gravity of any solid or liquid, referred to water as unity, also represent the weight of one cubic centimetre of the substance, expressed in grammes. Electricity, 435-540 ; phenomena of, 436 ; voltaic, 469 ; applications of, 505 ; in warfare, 537 ; in medicine, 538. Elements, the chemical, 10. Energy, 28^3 ; compared with work, 28 ; nature of, 31 ; increase of, with velocity, 32 ; forms of, 34-39 ; of onward motion, 35 ; of visible vibration, 35 ; of sound vibration, 36 ; of heat, 37 ; radiant, 38 ; conservation of, 39, 40 ; transformation of, 40 ; availability of, 41 ; potential, 42, 97 ; chemical, 70 ; measurement of, 94, 95 ; of rotation, 95 ; unit of, 95. Evaporation, phenomena of, 250. Expansion, of gases, 208, 243 ; of solids, by heat, 233; of liquids and gases, by heat, 234 ; law of, 237 ; coefficient of linear, 237 ; coefficient of cubical, 240 ; of water, 241. Force, definition of, 43, 44 ; action of, 44, 45 ; recognition of, 45, 46 ; examples of, 49-54 ; changing direction of motion, 55 ; production of, by energy, 56 ; unit of, 70 ; moment of, 111 ; central, 113. Forces, balanced, 47, 48 ; examples of, 49-54 ; measurement of, 82, 84, 85, 91 ; action of, 105 ; composition of, 105 ; equilibrium of, 106 ; resolution of, 107, 109. Galvanometer, the, 467, 499. Gases, 166 ; properties of, 200-228 ; compressibility of, 205 ; expansion of, 208 ; absorption of, 210 ; diffusion of, 220. Illumination, law of intensity of, 327. Images, by small apertures, 296 ; by reflection, 301 ; by two mirrors, 304 ; by concave mirrors, 305 ; by convex mirrors, 306 ; by lenses, 325-327. Light, 293-369 ; propagation of, 295 ; velocity of, 297 ; reflection of, 299 ; refraction of, 310 ; under water, 315 ; loss of. by multiple reflection, 321 ; decomposition of, by prisms, 328 ; polarization of, 361-365. Morse code of signals, 510. Motion, 14 ; relative, 15 ; direction of, 16 ; uniform, 17 ; uniformly accelerated, 19, 20 ; free, 31 ; laws of, 31, 87, 102 ; perpetual, 148. Power, 101. Pressure, law of transmission of, 182 ; equal transmission of, 183 ; due to weight of liquid, 184 ; intensity of, 185 ; upward, of liquids, 186 ; atmospheric, 201, 225 ; influence of, on fusing and boiling points, 254-258; of vapor below the freezing-point, 259; of vapors, 266. Rainbow, the, 367, 368. Reflection of light, 299 ; total, 313, 314. Refraction of light, 310 ; law of, 310, 312. Resistance, electrical, 480 ; coils, 481 ; Sonometer, the, 391. Sound, 370-418 ; nature of, 370 ; velocity of, 376 ; propagation of, 378 ; interference of, 384 ; reflection of, 387 ; refraction of, 388 ; diffraction of, 389 ; elements of, 398. Unit, of force, 90 ; of energy, 95 ; of work, 95, 96 ; British engineering, of mass, 98 ; British engineering, of work, 99 ; British engineering, of energy, 99 ; of electrical resistance, 480. Units, 87-91 ; distinguished from standards, 88 ; of length, time, and mass, 89 ; British engineering, 98 ; French engineering, 100 ; thermal, 244. Animal life in the sea and on the land. A zoology for young people. Especial attention has been given to the structure of animals, and to the wonderful adaptation of this structure to their habits of life. For the use of schools and families. Illustrated by three hundred engravings. The book includes only that which every well-informed person ought to know, and excludes all which is of interest only to those who intend to be thorough zoologists. Prepared for the use of pupils who wish to gain a general knowledge concerning the common animals of the country. The examples presented for study are such as are common and familiar to every school-boy. This book proceeds, by natural development, from the lowest form of organism to man. A cut is given of every animal named, since a good picture of an object is worth more than pages of description. This is a treatise on the principles of the science adapted to the wants of the American student, with special reference to American geological history. The illustrations are numerous, accurate, and well executed. Designed to make science interesting by omitting those details which are valuable only to the scientific man, and by presenting only those points of general importance with which every well-informed person wishes to be acquainted. A treatise on the industrial relations of geological structure, and on the nature, occurrence, and uses of substances derived from geological sources. It gives a connected and systematic view of the applications of geology to the various uses of mankind. A new manual of the elements of Astronomy, descriptive and mathematical, comprising the latest discoveries and theoretical views, with directions for the use of globes, and for studying the constellations. Accompanied with numerous illustrations, a colored representation of the solar, stellar, and nebular spectra, and Arago's celestial charts of the Northern and Southern Hemispheres. Especially adapted to the wants of American schools. This book is not written for the information of scientific men, but for the inspiration of youth. The author has sought to weave the story of those far-distant worlds into a form that may attract the attention and kindle the enthusiasm of the pupil. Physical Geography. In addition to the series of Political Geographies published by the American Book Company, their list includes the following standard and popular text-books on Physical Geography : Prepared by a corps of scientific experts with richly-illustrated engravings, diagrams, and maps in color, and including a separate chapter on the geological history and the physical features of the United States. By RUSSELL HINMAN. A new work in a new and convenient form. All irrelevant matter is omitted and the pages devoted exclusively to Physical Geography clearly treated in the light of recent investigations. The numerous charts, cuts, and diagrams are drawn with accuracy, fully illustrating the text. By ARNOLD GUYOT. Revised, with new plates and newly-engraved maps. A standard work by one of the ablest of modern geographers. All parts of the subject are presented in their true relations and in their proper subordination. A new and comprehensive work, embracing the results of recent research in this field, including Physiography, Hydrography, Meteorology, Terrestial Magnetism, and Vulcanology. The topical arrangement of subjects adapts the work for use in grammar grades as well as for high and normal schools. demonstrations. HUNTER'S Elements of Plane Geometry. By THOMAS HUNTER, Ph. D. I2mo, cloth. 132 pages . . 60 cents This volume is intended only for beginners— for those who are preparing for college, and for intermediate and high schools generally. Extreme brevity has here been combined with a lively and simple narrative, such as might supply the present need of young pupils while affording a symmetrical plan for the research of older ones. Ancient, Mediaeval and Modern, with special reference to the History oi Mankind. Its anatomical synopses, its maps showing the political divisions at the great epochs, its collateral information, its surveys of the great events, distinguished men, and important discoveries.furnish in an entertaining style just what is valuable to the beginner of the study of history. A suggestive outline of great compactness. Each country is treated by itself, and the United States receives special attention. Frequent maps, contemporary events in tables, references to standard works for fuller details, and a minute index constitute the " Illustrative Apparatus." The style is surprisingly vivid and at times even ornate. This work, designed as a text-book and for private reading, is a clear and condensed narrative, brought down to the present year, comprising not only a record of political events, but also a sketch of the progress of literature, art and science from the beginning of history to the present time. A complete outline of the world's history. Some of the prominent features comprise : blackboard analysis ; summaries to assist in review ; lists of reading references ; colored maps ; scenes in real life ; chapters on civilization ; genealogical tables ; foot-notes ; chapters devoted to the rise of modern nations. From the earliest ages to the present time. A clear, fresh, carefully arranged and condensed work, beautifully illustrated. It treats ancient civilization in the light of the most recent discoveries. The whole history of the past condensed into a moderate-sized volume that can be readily mastered in the ordinary school year. Copies of these or any of the publications of the American Book Company for the use of teachers or school officers, or for examination with a view to introduction^ will be sent by mail ', postpaid, on receipt of the list or introduction price. A compact volume, comprehensive in scope, but sufficiently brief to be completed in one school term. Its statements of historical facts are based upon the studies of the most recent and reliable authorities. The maps are superior in fullness, accuracy and beauty. This book is primary in matter and manner of treatment. Especially interesting are the chapters on manners and customs of the people at different periods, and the linking of events by tracing cause and effect. With maps of France showing the provinces and the departments. A short but comprehensive history of France, designed for use in schools where but little time is devoted to this subject or as a reference book. Topical headings are placed at the beginning of the paragraphs. Copies of these or any of the publications of the American Book Company for the use of teachers or school officer s^ or for examination with a view to introduction, will be sent by mail \ postpaid, on receipt of the list or introduction price.	218,291	common-pile/pre_1929_books_filtered	appletonsschoolp00quacrich	public_library	public_library_1929_dolma-0017.json.gz:1975	https://archive.org/download/appletonsschoolp00quacrich/appletonsschoolp00quacrich_djvu.txt

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